PATENT DOCUMENT

Publication Number: US-11934230-B2
Application Number: US-202217653859-A
Country: US
Kind Code: B2

Title: Reconfigurable stand ecosystem

Abstract:
Support systems and stands for electronic devices include tilt hinges, lift arms, and their component parts. Some tilt hinges include assemblies for guiding and retaining bars or protrusions into preferred positioning within receiver openings to unify the parts, particularly as they move, and to reduce wobble or slop in the joints. Lift arms provide simplified and low-cost guidance and counterbalance mechanisms for controlling movement of the electronic device relative to the base of a stand. In some cases, the lift arms have sheaths to help protect or cover mechanisms while allowing additional space for the mechanisms within the lift arm. Other interconnection systems hide and protect a connector interface between the stand and the electronic device within a housing until unlocked and the connector is moved into an exposed position. These systems improve efficiency, comfort, ergonomics, accessibility, and user satisfaction of the electronic devices and their supports.

Claims:
What is claimed is: 
     
       1. A device interconnection system, comprising:
 a mounting bar connectable to an electronic device; 
 a stand structure including an arm block, wherein the mounting bar is rotatable about an axis of rotation relative to the arm block; 
 a sleeve; 
 a biasing member having a first end affixed to the sleeve and having a second end affixed to the arm block; 
 a central pin extending through the sleeve and the biasing member, wherein the central pin is rotatable about the axis of rotation relative to the arm block; 
 wherein the sleeve is adjustable between a first configuration wherein the sleeve is rotatable about the axis of rotation relative to the mounting bar and a second configuration wherein rotation of the sleeve about the axis of rotation is fixed relative to the mounting bar and the central pin. 
 
     
     
       2. The device interconnection system of  claim 1 , wherein the sleeve is adjustable between the first configuration and the second configuration by adjustment of a fastener. 
     
     
       3. The device interconnection system of  claim 1 , wherein the first end is incapable of slipping relative to the sleeve, and the second end is incapable of slipping relative to the arm block. 
     
     
       4. The device interconnection system of  claim 1 , wherein a block portion connected to the mounting bar is rotatable into contact with a stop surface of the arm block configured to limit rotation of the block portion about the axis of rotation. 
     
     
       5. The device interconnection system of  claim 1 , wherein the stand structure comprises a first end block and a second end block. 
     
     
       6. The device interconnection system of  claim 5 , wherein the mounting bar is configured to fit laterally between the first end block and the second end block. 
     
     
       7. The device interconnection system of  claim 5 , wherein the central pin extends between the first end block and the second end block. 
     
     
       8. The device interconnection system of  claim 7 , wherein the central pin is rotatable relative to the first end block and the second end block. 
     
     
       9. The device interconnection system of  claim 7 , further comprising an adjustable clamping device configured to adjustably affix the sleeve and the central pin. 
     
     
       10. The device interconnection system of  claim 1 , further comprising a movable block mounted to the mounting bar, the movable block being rotatable about the axis of rotation. 
     
     
       11. The device interconnection system of  claim 1 , wherein the arm block comprises a stop surface configured to limit rotation of the mounting bar. 
     
     
       12. The device interconnection system of  claim 1 , wherein the biasing member comprises at least one elastically resilient biasing member. 
     
     
       13. The device interconnection system of  claim 1 , wherein the biasing member is coiled around the central pin and the axis of rotation. 
     
     
       14. The device interconnection system of  claim 1 , wherein the first end comprises a first inner diameter and the second end comprises a second inner diameter, the first inner diameter different than the second inner diameter. 
     
     
       15. The device interconnection system of  claim 1 , wherein the sleeve comprises a fastener configured to adjustably tune a neutral position of the biasing member. 
     
     
       16. A tilt hinge, comprising: a stand comprising a first end block and a second end block; a central pin extending between the first end block and the second end block; a bar connectable to an electronic device and rotatable about the central pin; a spring having a first end fixed relative to the bar and having a second end fixed relative to the stand; wherein the spring is configured to provide a first counterbalance moment in a first direction when the electronic device is in a first position and a second counterbalance moment in a second direction when the electronic device is in a second position; and a clamping device configured to adjust a neutral position of the spring. 
     
     
       17. The tilt hinge of  claim 16 , wherein when a center of mass of the electronic device is centered over an axis of rotation of the bar, the spring does not apply any moment on the electronic device. 
     
     
       18. A hinge, comprising: a stand comprising a first end block and a second end block; a central pin extending between the first end block and the second end block, the central pin being rotatable about an axis of rotation; a bar connectable to an electronic device and rotatable relative to the first end block and the second end block about the axis of rotation; a biasing member having a first end affixed to a first sleeve and having a second end fixed to a second sleeve, the first sleeve rotatable about the axis of rotation and the second sleeve fixed relative to the first end block and the second end block; and a clamping device configured to affix the first sleeve to the central pin; wherein the first sleeve is adjustable between a first configuration wherein the first sleeve is rotatable about the axis of rotation relative to the bar and a second configuration wherein rotation of the first sleeve about the axis of rotation is fixed relative to the bar and the central pin. 
     
     
       19. The hinge of  claim 18 , wherein the bar comprises a block portion rotatable into contact with a stop surface of the first end block, the stop surface configured to limit rotation of the bar about the axis of rotation.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This claims the benefit of U.S. Provisional Patent Application No. 63/172,413, filed Apr. 8, 2021, entitled “RECONFIGURABLE STAND ECOSYSTEM,” the entire disclosure of which is hereby incorporated by reference. 
    
    
     FIELD 
     The described embodiments relate generally to stands, arms, and other supports for electronic devices. More particularly, the present embodiments relate to connection assemblies for adjusting the tilt, height, and attachment status of computing devices and their supports. 
     BACKGROUND 
     Computing device makers are constantly seeking out improvements to the user&#39;s experience with the assembly, portability, ergonomics, aesthetics, and durability of their devices. For some devices, such as a computer monitor, display screen, touch screen, or “all-in-one” computer (i.e., a computer monitor that also contains a processor and other computing components), the rear-facing side of the housing of the device can be covered with unsightly and distracting cords, hinges, markings, ports, labels, fasteners, and other components. Although a device maker may find ways to reduce or eliminate those undesirable features, the redesigned device usually lacks versatility, such as only being compatible with one stand, and, in many cases, not being able to be removed from the stand at all. 
     Additionally, users often prefer the stands of their devices to have a quality, solid, and sturdy feel whether the stand is adjusted, tilted, lifted, moved, or replaced. Providing these features frequently comes at a high cost due to high part complexity, difficulty to manufacture or transport, expensive custom parts and materials, and more. 
     SUMMARY 
     Aspects of the present disclosure relate to connectors and connector systems for an electronic device stand. In an embodiment of the disclosure, the connector comprises a first shaft attachable to an electronic device, with the first shaft having a first set of guide surfaces, a second shaft attachable to a support bar, with the second shaft having a second set of guide surfaces, and a fastener inserted into an opening formed in at least one of the first and second shafts. The first set of guide surfaces can be driven into the second set of guide surfaces in response to rotation of the fastener in the opening, wherein contact between the first set of guide surfaces and the second set of guide surfaces secures the first shaft to the second shaft in at least five degrees of freedom. 
     In some embodiments, the fastener comprises a head portion, a shank, and a threaded portion, wherein the shank has an increased diameter portion relative to the threaded portion, wherein the threaded portion engages the first shaft, wherein the increased diameter portion engages the second shaft, wherein guide surfaces of the first set of guide surfaces are non-orthogonally angled relative to each other, and wherein guide surfaces of the second set of guide surfaces are non-orthogonally angled relative to each other and are positioned in an aperture in the second shaft. 
     In some embodiments, contact between the first set of guide surfaces and the second set of guide surfaces can secure the first shaft to the second shaft in six degrees of freedom. The opening can comprise a first surface positioned at a non-orthogonal angle relative to an axis of rotation of the fastener, wherein movement of the fastener parallel to the axis of rotation moves the first surface in a direction substantially perpendicular to the axis of rotation. 
     In some embodiments, the first shaft and the second shaft can form a pivotable joint having a pivot axis coaxial with a central longitudinal axis of the fastener. The fastener can comprise a fastener shoulder contacting an opening shoulder in the opening and preventing movement of the first shaft relative to the second shaft. 
     Another aspect of the disclosure relates to a connection system to link an electronic device to a support device, wherein the system comprises an electronic device including a housing, a display screen positioned in the housing, and a first connector extending from the housing, the first connector having a first pair of tapered surfaces. The system also comprises a support device including an arm structure and a second connector attachable to the first connector of the electronic device, with the second connector having a second pair of tapered surfaces and the first connector and the second connector forming a pivotable arm. The system can also include a fastener contacting the first and second connectors, wherein in response to installation of the fastener to the first and second connectors, the first pair of tapered surfaces can be driven into contact with the second pair of tapered surfaces. 
     In some embodiments, the first connector can comprise a first connector axis positioned between the first pair of tapered surfaces, and the second connector can comprise a second connector axis positioned between the second pair of tapered surfaces. In response to installation of the fastener to the first and second connectors, the first connector axis can be aligned with the second connector axis. In some embodiments, the first pair of tapered surfaces expands into contact with the second pair of tapered surfaces in response to installation of the fastener or the second pair of tapered surfaces expands into contact with the first pair of tapered surfaces in response to installation of the fastener. 
     The fastener can further comprise a longitudinal axis and a driving surface, with the driving surface being configured to engage a sloped surface of the first connector or the second connector and with the sloped surface being angled relative to the longitudinal axis of the fastener. In some embodiments, rotation of the fastener about an axis of rotation is configured to drive the first and second pairs of tapered surfaces into contact with each other. The rotation of the fastener about an axis of rotation can drive the first or second connector in a direction perpendicular to the axis of rotation. The fastener can also comprise a cam surface configured to move into contact with the first or second connector as the fastener is installed. 
     Yet another aspect of the disclosure relates to a support for an electronic device, wherein the support comprises an arm structure, a device attachment structure joined to or connectable to an electronic device and having a threaded opening, a joint including a first structure anchored to the arm structure and a second structure anchored to the device attachment structure, with the first structure being rotatable relative to the second structure about an axis of rotation, and a fastener having a shoulder portion engaging the second structure and a threaded portion engaging the threaded opening of the device attachment structure and holding the second structure in contact with at least two spaced apart surfaces of the device attachment structure. 
     In some embodiments, a rounded surface of the second structure contacts the at least two spaced apart surfaces of the first structure. The at least two spaced apart surfaces of the first structure can be positioned within an opening in the first structure. The shoulder portion can comprise a first shoulder face contacting an opposing shoulder face of the first structure. The joint can comprise an energy storage device that has a central axis coaxial with the axis of rotation of the joint. The fastener can comprise a central axis coaxial with the axis of rotation of the joint. An outer surface of the second structure can be movable between a contacting position and a separated position relative to an inner surface of the first structure in response to rotation of the device attachment structure about the axis of rotation of the joint. 
     Yet another aspect of the disclosure relates to a support stand for an electronic device. The support stand can comprise an arm assembly including: a device attachment structure having a first attachment point and a second attachment point; a support structure having a third attachment point and a fourth attachment point; a first arm pivotally connected to the first attachment point and the third attachment point; and a second arm pivotally connected to the second attachment point and the fourth attachment point. The support stand can also include a counterbalance mechanism including: a spring having a first end and a second end; a retainer pivotally connected to the arm assembly at a first pivot point and engaging the first end of the spring; and a rod connecting the second end of the spring to the arm assembly at a second pivot point, with the first pivot point being spaced apart from the second pivot point. Rotation of the arm assembly about the third and fourth attachment points in a first rotational direction can store energy in the spring via movement of the rod relative to the retainer. 
     In some embodiments, the first, second, third, and fourth attachment points form a parallelogram. The arm assembly can further comprise a retainer bar attached to the first arm and to the second arm, with the first pivot point being positioned on the retainer bar. The retainer can comprise a protrusion or ledge engaging the first end of the spring. The rod can be non-parallel to at least the first arm. The rod can rotate at a different angular velocity than the first arm in response to rotation of the first arm about the third attachment point. An angle between a longitudinal axis of the first arm and a longitudinal axis of the rod can decrease in response to rotation of the first arm about the third attachment point. 
     Another aspect of the disclosure relates to an arm for a support stand. The arm can comprise a housing having a hollow interior and an end opening aligned with a longitudinal axis of the housing, with the hollow interior having an internal surface; and a device connector assembly including: a sheath positioned at least partially within the hollow interior, covering the end opening, and having an end portion contacting the internal surface; and a device connector extending through the sheath and protruding from the end opening of the housing, with the device connector being rotatable relative to the housing between a first rotated position and a second rotated position. The end portion of the sheath can remain in contact with the internal surface as the device connector rotates between the first and second rotated positions. 
     The sheath can be configured to apply radially-outward-directed pressure against the internal surface. The end portion of the sheath can slide along the internal surface parallel to the longitudinal axis of the housing as the device connector rotates. The end portion can be concave. The end portion of the sheath can be configured to apply outward pressure to the internal surface. The sheath can be resiliently flexible. The housing can include a second end opening, and the arm can further comprise: a second sheath positioned at least partially within the hollow interior, covering the second end opening, and having a second end portion contacting the internal surface; and a stand connector extending through the second sheath and being rotatable relative to the housing between a first rotated position and a second rotated position. 
     Yet another aspect of the disclosure relates to a lift system, comprising: a device attachment structure; a support structure; a housing pivotally connected to the device attachment structure at a first pivot point and connected to the support structure at a second pivot point; and a belt engaging the device attachment structure and the support structure, wherein the device attachment structure rotates relative to the housing in response to rotation of the housing relative to the support structure due to tension in the belt. 
     In some embodiments, a tilt joint can be positioned on the device attachment structure. The housing can include a least one protrusion configured to apply an inward-directed force to the belt. The belt can comprise a first set of engagement features engaging a second set of engagement features on at least one of the device attachment structure and the support structure. Also, with the housing in a first position relative to the device attachment structure, the belt can be under tension at a first point on the device attachment structure, and with the housing in a second position relative to the device attachment structure, the belt can be under tension at a second point on the device attachment structure, with the first point and the second point being offset from each other. The belt can be prevented from sliding against the device attachment structure and the support structure. 
     Another aspect of the disclosure relates to a connection assembly for joining an electronic device to a support structure, wherein the connection assembly comprises an electronic device including a housing, a latch positioned within the housing, and an adjustment mechanism to move the latch relative to the housing between a first position and a second position, with the housing including an opening, and a support stand including a protrusion, with the protrusion including a longitudinal axis and a lock surface oriented non-orthogonally relative to the longitudinal axis. With the latch in the first position, the protrusion can be insertable into the housing to a depth exceeding a portion of the latch, and with the latch in the second position, the protrusion can be locked in place relative to the housing by engagement of the latch against the lock surface. The protrusion can also be drawn into the opening by engagement between the latch and the lock surface in response to movement of the latch from the first position to the second position. 
     In some embodiments, the protrusion further comprises a tapered end portion, wherein the tapered end portion is drawn into a tapered opening of the electronic device in response to movement of the latch from the first position to the second position. The latch can translate within the housing between the first and second positions. The adjustment mechanism can be rotatable to translate the latch within the housing. The latch can rotate within the housing between the first and second positions. The adjustment mechanism can include a lever accessible from an exterior of the housing to adjust the position of the latch or a threaded shaft configured to translate the latch between the first and second positions. The latch further can further comprise an engagement surface oriented substantially parallel to the lock surface, wherein the engagement surface engages the lock surface when latch is in the second position. The latch can further comprise an ejection surface oriented non-orthogonally relative to the longitudinal axis of the protrusion, wherein the protrusion is pushed out of the opening by engagement between the ejection surface and the protrusion in response to movement of the latch from the second position toward or beyond the first position relative to the second position. In some embodiments, the protrusion comprises an aperture extending through the protrusion substantially perpendicular to the longitudinal axis, wherein the lock surface is positioned within the aperture. 
     Still another aspect of the disclosure relates to a connection assembly for joining an electronic device to a support structure. The connection assembly can comprise an electronic device including an enclosure, a bar rotatably connected to the enclosure, and a lock pivotable relative to the enclosure and relative to the bar, with the enclosure having an opening and with the bar having a lock recess. The assembly can also include a support structure having a shaft insertable into the opening and attachable to the bar at an attachment interface, wherein with the lock positioned in the lock recess of the bar, the bar is prevented from pivoting relative to the enclosure and wherein with the lock removed from the lock recess of the bar, the bar is pivotable to a position exposing the attachment interface through the opening of the enclosure. 
     In some embodiments, the shaft is reversibly removable from the bar when the bar is in the position exposing the attachment interface through the opening of the enclosure. The attachment interface can comprise a fastener joining the shaft to the bar, wherein the fastener is removable in response to exposing the attachment interface through the opening of the enclosure. A gap may be formed between the opening of the enclosure and the shaft or bar, wherein the lock is movable in response to a probe being inserted into the gap. The lock can be configured to automatically lock the bar upon pivoting the attachment interface into the enclosure relative to the opening. A first axis of rotation of the bar and a second axis of rotation of the lock can be parallel to each other. 
     Another aspect of the disclosure relates to a device interconnection system comprising: a bar connectable to an electronic device; a stand structure including an arm block, wherein the bar is rotatable about an axis of rotation relative to the arm block; a sleeve; and a biasing member having a first end affixed to the sleeve and having a second end affixed to the arm block. The sleeve can be adjustable between a first configuration, wherein the sleeve is rotatable about the axis of rotation relative to the bar, and a second configuration, wherein rotation of the sleeve about the axis of rotation is fixed relative to the bar. 
     In some embodiments, the sleeve can be adjustable between the first configuration and the second configuration by adjustment of a fastener. The first end can be made incapable of slipping relative to the sleeve, and the second end can be made incapable of slipping relative to the arm block. A block portion can be connected to the bar and can be rotatable into contact with a stop surface of the arm block configured to limit rotation of the block portion about the axis of rotation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIGS.  1 A,  1 B, and  1 C  show side views of an electronic device and support system in three different pivoted configurations. 
         FIG.  2    shows a partial exploded side view of an interface between the electronic device and the support system. 
         FIG.  3 A  shows a partial perspective view of a bar configured to connect to an electronic device. 
         FIG.  3 B  shows a partial side section view of the bar of  FIG.  3 A  installed in the electronic device. 
         FIG.  4    shows a partial top section view of an interface between an electronic device and a support system. 
         FIG.  5 A  shows a partial top section view of another interface between an electronic device and a support system. 
         FIG.  5 B  shows a partial side section view of the interface of  FIG.  5 A . 
         FIG.  5 C  shows a partial top section view of the interface of  FIG.  5 A  in a second configuration. 
         FIG.  5 D  shows a partial side section view of the interface of  FIG.  5 C . 
         FIG.  6 A  shows a partial side view of another interface between an electronic device and a support system. 
         FIG.  6 B  shows a partial side view of the interface of  FIG.  6 A  in a second configuration. 
         FIG.  7 A  shows a schematic top view of a bar attaching an electronic device to a support system. 
         FIG.  7 B  shows a schematic top view of another bar attaching an electronic device to a support system. 
         FIG.  8    shows a partial exploded top section view of a connection system between an electronic device and a support stand. 
         FIG.  9    shows a partial top section view of the connection system of  FIG.  8    in an assembled state. 
         FIG.  10    shows an exploded top section view of portions of a tilt hinge of the connection system of  FIG.  8     
         FIG.  11    shows a section view as taken through section lines  11 - 11  in  FIG.  9   . 
         FIG.  12    shows a section view as taken through section lines  12 - 12  in  FIG.  9   . 
         FIG.  13 A  shows a side section view of a lift arm connecting an electronic device to a support stand. 
         FIG.  13 B  shows the system of  FIG.  13 A  in a second configuration. 
         FIG.  14 A  shows a side view of another lift arm connecting an electronic device to a support stand with some components omitted. 
         FIG.  14 B  shows a side section view of the lift arm of  FIG.  14 A  with additional components shown. 
         FIG.  14 C  shows the system of  FIG.  14 B  in a second configuration. 
         FIG.  15 A  shows a side section view of another lift arm connecting an electronic device to a support stand. 
         FIG.  15 B  shows the system of  FIG.  15 A  in a second configuration. 
         FIG.  16 A  shows a partial exploded top section view of an interconnection system between an electronic device and a support stand. 
         FIG.  16 B  shows a partial side section view of the system of  FIG.  16 A  as taken through section lines  16 B- 16 B in  FIG.  16 A . 
         FIG.  17 A  shows a partial top section view of the interconnection system of  FIG.  16 A  in an assembled configuration. 
         FIG.  17 B  shows a partial side section view of the system of  FIG.  17 A  as taken through section lines  17 B- 17 B in  FIG.  17 A . 
         FIG.  17 C  shows a partial side section view of the system of  FIG.  17 A  as taken through section lines  17 C- 17 C in  FIG.  17 A . 
         FIG.  18    shows a partial side section view of the interconnection system of  FIG.  17 A  in a different assembled configuration. 
         FIG.  19    shows a partial side section view of the interconnection system of  FIG.  17 A  in another different assembled configuration. 
         FIG.  20    shows a partial side section view of another interconnection system using a lock mechanism/latch operated by a lever. 
         FIG.  21    shows a partial side section view of another interconnection system using a rotatable lock mechanism/latch. 
         FIG.  22    shows a partial perspective view of an end of a protrusion for an interconnection system of another embodiment of the present disclosure. 
         FIG.  23 A  shows a partial perspective section view of the interconnection system using the protrusion of  FIG.  22    as taken through section lines  23 A- 23 A in  FIG.  23 B . 
         FIG.  23 B  shows a partial front view of the interconnection system of  FIGS.  22  and  23 A  in an unlocked configuration. 
         FIG.  24 A  shows a partial perspective section view of the interconnection system using the protrusion of  FIG.  22    as taken through section liens  24 A- 24 A in  FIG.  24 B . 
         FIG.  24 B  shows a partial front view of the interconnection system of  FIGS.  22  and  23 A  in a locked configuration. 
         FIG.  25 A  shows a partial side section view of a connection system between a support stand and an electronic device in a locked state. 
         FIG.  25 B  shows a partial side section view of the connection system of  FIG.  25 A  in an unlocked state. 
         FIG.  25 C  shows a partial side section view of the connection system of  FIG.  25 A  in an unlocked and user-accessible state. 
         FIG.  26 A  shows a partial perspective view of another interconnection system. 
         FIG.  26 B  shows a top section view of the system of  FIG.  26 A . 
         FIG.  27    shows a partially exploded top section view of a tilt hinge assembly. 
         FIG.  28    shows an assembled top section view of the tilt hinge assembly of  FIG.  27   . 
         FIG.  29    shows an exploded top section view of internal components of the tilt hinge assembly of  FIG.  27   . 
         FIG.  30    shows a side section view of the tilt hinge assembly of  FIG.  28    as taken through plane P and with the bar and pin rotated upward about the axis of rotation of the pin. 
         FIG.  31    is a schematic side view of an electronic device, lift arm, and stand. 
         FIG.  32 A  shows a perspective view of an end of a lift arm at a tilt hinge with the bar in a first rotated position. 
         FIG.  32 B  shows a perspective view of the end of the lift arm of  FIG.  32 A  with the bar in a second rotated position. 
         FIG.  33    shows an exploded perspective view of counterbalance assembly components of the tilt hinge of  FIG.  32 A . 
         FIG.  34    shows a perspective section view of the tilt hinge as taken through section lines  34 - 34  in  FIG.  32 A . 
     
    
    
     DETAILED DESCRIPTION 
     Electronic device stands with poor quality and ergonomics often exhibit “slop,” “hysteresis,” or “blowback” in their hinges when the vertical or horizontal tilt the device is adjusted relative to the stand. Assemblies, devices, and methods described herein can improve electronic device configurability, provide reliable and high-quality adjustable support, and avoid incorporating unsightly elements, frustrating mechanics, and poor ergonomics. 
     One aspect of the present disclosure relates to a connector for an electronic device stand that reduces or eliminates this “blowback” by securely retaining a bar (i.e., a tongue, protrusion, or shaft) extending from an electronic device (e.g., computing device or display screen) within an opening in a shaft or receiver unit of the support stand. The connector can include elements for driving at least a pair of guide surfaces of the bar into a corresponding pair of guide surfaces on the support stand, such as by using a shaft or fastener inserted into an opening formed in at least one of the bar or the receiver unit. The contact between the guide surfaces can ensure that the bar and the opening are correctly aligned and in tight contact with each other that eliminates wobble and shifting in the joint. 
     The joint can comprise a threaded fastener that, when tightened in place, pulls or pushes guide surfaces of the bar (e.g., a pair of sloped or curved surfaces on the end of the tongue) into guide surfaces of the support stand (e.g., a pair of sloped or curved surfaces located in an opening in the support stand into which the bar is inserted). Engaging the guide surfaces against each other can substantially reduce the degrees of freedom of the bar relative to the support stand (e.g., restricting the bar in five degrees of freedom or more) while also reducing the possibility of the bar coming loose due to poor fastener reliability. Accordingly, the joined bar and support stand shaft (i.e., the portion of the joint having the opening) can effectively move as a single, rigid member once they have been joined together, thereby improving the user ergonomics, joint reliability, and perceived quality of the device. The bar and support stand shafts can be pivotally connected to a support bar (e.g., a base of the support stand) so that the electronic device is pivotable relative to the support bar while also being removable from the support bar. 
     In some embodiments, the joint between the stand and the bar can comprise features for improving the user-adjustability of the joint. For instance, the bar of the joint can comprise a fastener that is user-accessible (e.g., from the exterior of the joint without prior additional disassembly) to adjust the positioning of the guide surfaces within the joint or to move the bar relative to the guide surfaces. Identical fasteners can be positioned on opposite sides of the joint to simplify assembly (e.g., by permitting the user to assemble the joint with either of two fasteners being installed on either side) and to reduce the number of unique parts, thereby reducing the cost of the joint. In some embodiments, the fastener can extend through an axis of rotation of the support stand to keep the joint compact and simple to make and use. The fastener can include a head portion, a shank, and a threaded portion, wherein the shank has an increased diameter portion relative to the diameter of the threaded portion. The shank can therefore define an increased-diameter shoulder that is configured to engage a shoulder in an opening of the receiver unit and, while engaging threads in the bar, can be rotated to pull guide surfaces of the bar into contact with guide surfaces of the receiver unit. 
     In some configurations, the bar of the electronic device can comprise multiple openings or sets of openings that are configured to receive fasteners in different positions so that a variety of different stands or support adapters can be connected to the tongue. Accordingly, the tongue can be versatile in joining to various types of supports, such as a tilt stand, a combined tilt and lift stand, a display support arm, and/or a display mount adapter (e.g., a VESA mount or other flat display mounting interface (FDMI)). 
     Another aspect of the present disclosure relates to components of a support stand such as a lift arm portion that is configured to support and provide counterbalance to the electronic device as it is vertically translated relative to a ground surface. The lift arm portion can include a four-bar linkage assembly configured to preserve parallel motion of a device attachment structure at one end of the arm relative to a support structure at the opposite end thereof. The lift arm can also include an energy storage device (e.g., a spring) used to store energy as the electronic device moves downward and to release energy as the device moves upward, thereby making it easier for the user to adjust the height of the electronic device and to help stabilize and preserve the position of the electronic device once it has been adjusted to a desired position. The spring device can be positioned within a retainer that is pivotally connected to the four-bar linkage, and an end of the spring device can be attached to or engaged with a rod that is separately pivotable relative to the four-bar linkage. The pivoting connection points between the retainer and the rod can be properly spaced to ensure that, based on the energy storage properties of the spring device and the weight of the electronic device, rotation of the joints of the four-bar linkage stores a counterbalanced amount of energy in the spring device via rotation and relative movement of the rod and the retainer that compresses or extends the spring device. 
     In some embodiments, a parallel motion-enabling linkage can be used in the lift arm which does not include a set of four-bar linkages. For example, the lift arm can include a housing to which a device support and a stand support can be pivotally connected. The housing can be used and act similar to a pivotable linkage that is connected to the device and support stands. A belt, chain, or set of pivotable linkages can connect the device support and stand support to synchronize rotation of the electronic device and the stand support as the housing rotates, thereby preserving parallel movement in a manner similar to how another pivotable linkage extending between the supports would operate in a four-bar linkage. 
     Aspects of the disclosure also relate to ways to protect the interior of the lift arm from ingress while also improving aesthetics and limiting undesirable types of user access to mechanisms within the lift arm. The lift arm can have components positioned within an enclosure or housing with a hollow interior, and a device connector assembly can be at least partially positioned in the hollow interior with a sheath that covers, conceals, and protects components within an end opening of the housing and with a device connector (e.g., tongue) that extends through the sheath to attach to an electronic device. The sheath can be configured with a C-shaped side profile that has ends extending substantially parallel to a longitudinal axis of the housing and that can slide and bend as the device connector rotates relative to the housing to maintain coverage and concealment of the parts of the device connector assembly within the end opening of the housing. Due to the C-shaped profile of the sheath and the way it curls/uncurls as the device connector rotates relative to the housing, the inside of the housing remain more open and therefore able to receive the placement and movement of other internal elements such as a counterbalance spring device or similar structures. 
     Additional aspects of the disclosure relate to structures for attaching a tongue or other protrusion extending from a device stand to the inside of an electronic device housing. In an example embodiment, the housing can contain a lock mechanism (i.e., latch device) and an adjustment mechanism (e.g., screw or lever) operable to move the latch device within the housing. The protrusion of the stand can be inserted through an opening in the housing and past part of the latch device when the latch device is in an unlocked position. The protrusion can then be locked within the opening by moving the latch device to a locked position while the protrusion remains inserted in the opening. The locking of the protrusion can be caused by engagement of the latch device against a lock surface of the protrusion that is oriented non-orthogonally relative to the longitudinal axis of the protrusion, and the protrusion can be drawn into the opening the protrusion sliding against the lock surface as the latch device moves from the unlocked position to the locked position. Drawing the protrusion into the housing in this fashion can eliminate wobble and slop between the stand and the housing to ensure a solid and tight fit between their parts. 
     Additionally, the protrusion can have a tapered end portion that is drawn into contact with a tapered opening within the housing as the protrusion is being drawn into the electronic device. In this manner, the contact between the tapered surfaces can even further restrict relative motion between the devices and ensure that the stand and the electronic device are properly aligned and oriented relative to each other for optimal ergonomics, optimal part engagement, and improved joint strength. 
     Furthermore, in some embodiments a latch system is provided whereby the protrusion/shaft of the stand device is attachable to a bar pivotally positioned within the housing. A lock (e.g., a rotatable locking pin) can keep the protrusion and the bar from moving relative to the housing while the lock remains in a locked position against the bar or protrusion. The lock can be user-accessible to unlock the bar and protrusion and to permit user access to the attachment interface between the bar and protrusion by rotation of the bar and protrusion relative to the housing while the lock is in an unlocked position (e.g., rotated out of contact with the bar or protrusion). The lock can be hidden within the housing to help keep the exterior of the device free from distracting or unsightly features, and the lock can be accessible by a user with a tool (e.g., a flexible card, spudger, or other thin probe) inserted into a small opening or slot in the housing or between the protrusion and the opening in the housing. 
     The features and improvements described in detail herein can be used and implemented in any combination of the various embodiments of stand and support devices disclosed and described herein. Accordingly, it should be understood that the embodiments described herein and depicted in the figures are merely example embodiments showing features in relative isolation and are showing subsets of characteristics of various different embodiments that could be combined with other embodiments shown or described. The figures therefore do not depict exhaustive or mutually exclusive individual embodiments of the advancements and features of the present disclosure. 
     These and other embodiments are discussed below with reference to  FIGS.  1 A- 26 B . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be construed as limiting. Furthermore, as used herein, a system, a method, an article, a component, a feature, or a sub-feature comprising at least one of a first option, a second option, or a third option should be understood as referring to a system, a method, an article, a component, a feature, or a sub-feature that can include one of each listed option (e.g., only one of the first option, only one of the second option, or only one of the third option), multiple of a single listed option (e.g., two or more of the first option), two options simultaneously (e.g., one of the first option and one of the second option), or a combination thereof (e.g., two of the first option and one of the second option). 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims. 
       FIGS.  1 A- 1 C  show diagrammatic side views of an electronic device support system  100 . The support system  100  can include an electronic device  102  configured to be supported by a stand  104  which is supported by a ground surface  106 . The system  100  can include a bar  108  connecting the electronic device  102  to a tilt joint  110 . The tilt joint  110  can be positioned at the end of a lift arm  112  which has a height joint  114  connecting the lift arm  112  to support base  116  via a stand base connector  118 . The lift arm  112  can be a lift arm including a mechanism for parallel motion (e.g., a four-bar linkage and counterbalance assembly) described, for example, in U.S. patent application Ser. No. 16/583,222, entitled “Display Lift Arm” and filed 25 Sep. 2019, the entire disclosure of which is hereby incorporated by reference. 
     The electronic device  102  is shown in a first position in  FIG.  1 A  wherein the lift arm  112  is substantially horizontal and parallel to the ground surface  106 , and the electronic device  102  is tilted rearward at an angle at the tilt joint  110 . In  FIG.  1 B , the electronic device  102  remains at the same angle relative to the ground surface  106 , but the lift arm  112  has been rotated downward at the height joint  114 , thereby moving the electronic device  102  closer to the ground surface  106 . In  FIG.  1 C , the lift arm  112  remains in the same position as in  FIG.  1 B , but the tilt joint  110  has been operated to pivot the electronic device  102  forward to an orientation that is vertical and with a plane of the front or rear surface of the electronic device being oriented substantially perpendicular to the ground surface  106  and parallel to a vertical longitudinal axis of the support base  116 .  FIGS.  1 A- 1 C  are just a few examples of adjustable positions achieved through device support system  100 , and the electronic device  102  may be adjusted to higher (or lower) positions than shown, and may rotate further about the tilt joint  110  than is shown. 
     The electronic device  102  can comprise a display screen  119  (i.e., monitor or touch screen) for a computing device. In some embodiments, the electronic device  102  can comprise an entire computing device, such as by comprising a tablet computer or “all-in-one” computer including processing components, memory components, networking devices, and other computer parts known in the art. The electronic device  102  can include a housing  120 , enclosure, or shell configured to contain the display screen and other electronic components. The housing  120  can therefore have an interior chamber in which other components are positioned. In some embodiments, the housing  120  can also contain a latch or other mechanism for connecting the housing  120  to a bar  108  extending from the tilt joint  110 . The display screen  119  can have a front surface plane that is substantially parallel to a rear surface plane of a rear wall of the housing  120  (e.g., the substantially vertical plane from which the bar  108  horizontally extends in  FIG.  1 C ). 
     The stand  104  can comprise two joints (e.g.,  110 ,  114 ) as shown in  FIGS.  1 A- 1 C , and in some cases, the stand  104  can comprise one joint (e.g., only tilt joint  110 ) or more than two joints. When only a tilt joint  110  is included, the joint can join the bar  108  directly to the support base  116  at the base connector  118 . When more than two joints are included, the additional joint can be positioned between the joints  110 ,  114  shown in  FIG.  1 A , and the lift arm  112  can be divided into two segments. In some embodiments, the electronic device  102  is attached directly to the support base  116  without any pivotable joints. 
     The stand  104  can be configured with a base portion or foot and a vertical post or column as shown in the side views of  FIGS.  1 A- 1 C  with the base connector  118  extending from the support base  116  in a horizontal direction. In some embodiments, the base connector  118  can extend vertically upward from a top end of the support base  116 . The weight of the support base  116  can balance and support the weight of the electronic device  102  and the rest of the stand  104 . In some embodiments, the support base  116  can be clamped or fastened to a ground surface  106  to provide stability against tipping. In some embodiments, the support base  116  can be attached to a wall or other non-horizontal surface. The support base  116  can extend at least partially underneath the lift arm  112  (e.g., the foot of the base  116 ) and, in some cases, under the electronic device  102 . 
     The ground surface  106  can alternatively be vertical or oriented at a different angle. In some embodiments, the ground surface  106  is part of a desk or other office furniture. In some cases, the ground surface  106  can be positioned on a wall, post, counterweight, leg, device housing, or other structure to which the stand  104  needs to be attached. The stand  104  can, therefore, in some cases be attached to the ground surface  106  while in other cases, the stand  104  can simply be placed on or resting on the ground surface  106  without being attached to it. 
       FIG.  2    illustrates a diagrammatic partial exploded side view of the electronic device  102  and stand  104  components at the interface between the electronic device  102  and the stand  104  comprising the tilt joint  110 . The bar  108  is affixed to the electronic device  102  and can extend at a substantially perpendicular angle from the rear surface  200  of the electronic device  102 . The bar  108  can include a lateral opening  202  (i.e., a bore or aperture) near an end portion  204  thereof. The stand  104  can include a receiver  205  (i.e., a receiver unit) having a receiver opening  206  configured to receive the bar  108  to a sufficient depth that the lateral opening  202  of the bar  108  is aligned with a lateral opening  208  of the receiver  205 . With the openings  202 ,  208  aligned, a fastener, bar, or shaft can be inserted into both openings  202 ,  208  to prevent withdrawal of the bar  108  from the opening  206 . In some embodiments, the bar  108  (or other bars discussed herein, e.g., bar  800 ) can extend from a mount adapter that is attachable to an electronic device (e.g.,  102  or  802 ), such as one of the embodiments of mount adapters disclosed in U.S. patent application Ser. No. 16/563,252, entitled “Display Support Arm Mount” and filed 6 Sep. 2019, the entire disclosure of which is hereby incorporated by reference. The bar  108  (and other bars referred to herein) can be referred to as a first shaft or device attachment structure attachable to an electronic device (e.g.,  102 ), and the receiver  205  and/or tilt joint  110  (and other receivers/tilt joints herein) can be referred to as a second shaft attachable to a support bar (e.g., lift arm  112  or base  116 ). The tilt joint can include a first structure anchored to the lift arm  112  (e.g., arm barrel  842  anchored to lift arm  812 ) and a second structure anchored to the device attachment structure (e.g., receiver barrel  840  anchored to bar  800 ). 
     With the bar  108  positioned in the receiver opening  206 , the tilt joint  110  can be operated to rotate the receiver  205  and bar  108  relative to the lift arm  112 , as described in further detail in connection with embodiments described below. The rotation of the tilt joint  110  can change the angle of tilt of the electronic device  102  relative to a ground surface or base of the stand  104 . Thus, the interface shown in  FIG.  2    can be referred to as being a tilt assembly or tilt joint connection between the stand  104  and the electronic device  102 . In some embodiments, the positioning of the bar  108  and receiver  205  can be substantially reversed, wherein the electronic device  102  includes an opening into which a bar extends, as discussed, for example, in further detail below in connection with  FIGS.  16 A- 25 C . 
       FIG.  3 A  shows a simplified side perspective view of an example bar  300 . The bar  300  can be the bar  108  of  FIGS.  1 A- 2   . In this embodiment, the bar  300  is attached to and extends from a rear end surface of an electronic device  302  (e.g., device  102 ). The bar  300  includes a generally rectangular side profile with squared off corners  304 ,  306 . In some embodiments, the bar  300  (or bar  108 ) can include corners that are rounded (e.g., as shown in  FIG.  11   ), that are curved or chamfered, or that form a tapered shape (e.g., as shown in  FIGS.  5 A- 6 B and  16 B ). 
     With the bar  300  inserted into the receiver opening (e.g.,  206 ), a fastener or shaft  308  can be inserted into the lateral opening  310  of the bar  300 . The lateral opening  310  can be connected to a longitudinally-oriented slot  312  in the bar  300  that opens at the end between the corners  304 ,  306 , and the shaft  308  can have a diameter that exceeds the vertical diameter of the lateral opening  310 . Accordingly, as the shaft  308  moves into the opening  310 , the slot  312  can expand, thereby driving the corners  304 ,  306  apart from each other along a vertical axis  313  (which is in a direction substantially perpendicular to the direction of insertion  314  of the shaft  308 /the longitudinal axis of the shaft  308  or the longitudinal axis of the opening  310 ), as shown in the side section view of  FIG.  3 B . The expansion caused by the shaft  308  can cause the corners  304 ,  306  and/or the top and bottom surfaces  316 ,  318  of the bar  300  to come into contact with nearby bar-facing surfaces of the receiver opening  320  of the receiver, thereby causing a friction fit between the bar  300  and the opening that prevents withdrawal of the bar  300  from the opening while the shaft  308  is located in the lateral opening  310 . The friction fit can tightly hold the bar  300  against the receiver opening  320  to prevent removal of the bar  300  from the opening  320  without first removing the shaft  308 . 
     Furthermore, in some embodiments, the receiver opening  320  can comprise reverse-tapered inner surfaces  322 , as shown by broken lines in  FIG.  3 B , wherein expansion of the bar  300  causes an interference fit between the corners  304 ,  306  and/or top and bottom surfaces  316 ,  318  and the reverse-tapered surfaces  322 . In other words, the receiver opening can have an entrance opening width/height that is less than the width/height of a further interior portion of the opening, and the entrance opening can have a width substantially equal to the top-to-bottom thickness of the bar  300 , as shown in  FIG.  3 B . The expansion of the bar  300  can help ensure that the bar  300  is prevented from wobbling or shaking within the receiver opening  320 . The interference between the expanded corners  304 ,  306  and the surfaces  322  can provide an extra level of security to the attachment of the bar  300 . Removing the shaft  308  can allow the bar  300  to return to its normal thickness, thereby reducing or eliminating the friction and/or interference between the bar  300  and the opening  320 . 
     As shown in  FIG.  3 A , the bar  300  can have at least two end projections  324  that are spaced apart at the end of the bar  300 . Each end projection  324  can have its own lateral opening  310 , so two separate shafts  308  can be used to expand the projections  324 . Because the end projections  324  are spaced apart, the bar  300  can have improved flexibility in the projections  324  (and thus can expand more easily along the vertical axis  313 ) as compared to a bar  300  having a single opening  310  and slot  312  that extends across the entire width of the bar  300 . However, in some embodiments, the bar  300  can have a single, full-width (or partial-width) opening  310  and slot  312  instead of two projections  324  or through a part of the bar  300  in a proximal direction relative to the open ends of the slots  312  (i.e., nearer to the electronic device). Additionally, in some cases the bar  300  can have separate openings  310  on each side of the bar  300 , and projections  324  can be omitted (e.g., bar  800  in  FIG.  8   ). 
     The shaft  308  can be inserted into a shaft or fastener opening in the receiver (e.g.,  208 ) in addition to being inserted into the opening  310  of the bar  300 . In some embodiments, the shaft  308  and opening(s) (i.e., in the receiver and bar) are threaded and have threads engaging each other to ensure a secure fit of the shaft  308  in the openings along the direction of the longitudinal axis  314  of the shaft  308 . See, e.g.,  FIGS.  4  and  9   . Thus, an operator can use a driver tool or wrench to install or remove a shaft  308  from an opening  310 , and longitudinal-axial rotation of the shaft  308  can induce a vertical expansion/contraction of the bar  300  as the threads direct the shaft  308  into/out of the opening  310 . 
     Another embodiment of a bar-and-receiver support interface is shown in the top section view of  FIG.  4   . In this view, the bar  400  has a projection  424  inserted into a receiver opening  420  in receiver  405 , and a shaft  408  is installed through a lateral opening  412  in the receiver  405  and at least partially extends into a lateral opening  410  in the projection  424 . The shaft  408  comprises a threaded portion  430  engaging threads in the lateral opening  412  of the receiver  405  and has an end portion  432  that emerges into the lateral opening  410  of the projection  424 . 
     The end portion  432  has a frusto-conical tapered shape that narrows along the longitudinal axis  414  of the shaft  408  as it extends from the threaded portion  430  to its distal end. The lateral opening  410  can also comprise a sloped (i.e., ramped) inner surface  434  configured to be engaged by the radial outer surface of the end portion  432 . The sloped end portion  432  can be referred to as a driving surface of the shaft  408 . As a result, advancement of the shaft  408  into the opening  412  along its longitudinal axis  414  causes the end portion  432  to advance into the lateral opening  410  and to slide against the sloped inner surface  434 , thereby causing the projection  424  to drive and move in a direction perpendicular to the longitudinal axis  414  (e.g., along perpendicular second axis  416 ). The installation of the shaft  408  thus not only limits or prevents the bar  400  from being withdrawn from the receiver opening  420  but also urges the bar  400  into the receiver opening  420  in a tight and secure fit (e.g., until the end of the projection  424  contacts the inner surface of the receiver opening  420 ). In some embodiments, the receiver opening  420  can include ramped or tapered surfaces (e.g., opening bottom surface  433 ) that guide the projection  424  into a preferred vertical alignment (i.e., along an axis perpendicular to longitudinal axis  414  and second axis  416 ) with the opening  420 . See also  FIGS.  5 B and  5 D . The opening  420  can also have a ramped or tapered surface (not shown) on a side of the opening (e.g., at side surface  434 ) that contacts a side surface of the projection  424  to guide the projection into a preferred position in the opening  420  as measured along the direction of longitudinal axis  414 . See also  FIGS.  5 B and  5 D . 
     Features and elements from embodiments described herein can be combined with other features and elements described in connection with other embodiments. For example, the ramped surfaces (e.g., on end portion  432  and inner surface  434  of  FIG.  4   ) can be used in the embodiments shown in  FIGS.  2 ,  3 A, and  3 B . Similarly, the embodiment of  FIG.  4    can have an expandable bar end similar to that of  FIGS.  3 A and  3 B . This reciprocal feature relationship between embodiments applies to all embodiments described herein, as will be apparent to those having skill in the art who also have the benefit of hindsight after review of this disclosure. 
       FIGS.  5 A- 5 D  show another embodiment of a connection assembly wherein a bar  500  is inserted into a receiver opening  520 .  FIG.  5 A  shows a top section view with the shaft  508  and bar  500  in a first position,  FIG.  5 B  shows a section view taken through section lines  5 B- 5 B in  FIG.  5 A ,  FIG.  5 C  shows a top view of the assembly with the shaft  508  and bar  500  in a second position, and  FIG.  5 D  shows a section view taken through section lines  5 D- 5 D in  FIG.  5 C . 
     The bar  500  is configured to be inserted into opening  520  to a sufficient depth that a bar groove  510  longitudinally aligns with a lateral opening  512  of the receiver  505 , and the shaft  508  can be inserted into the position shown in  FIGS.  5 A and  5 B , wherein the shaft  508  has a first portion  530  positioned in the lateral opening  512  and an end portion  532  protruding into the bar groove  510 . The end portion  532  comprises a cam portion  535  with a cam protrusion  534  radially extending further from the central longitudinal axis  513  of the shaft  508  than the rest of the cam portion  535 . Initially, the cam protrusion  534  is oriented such that it is not contacting the bar groove  510 , as shown in  FIGS.  5 A- 5 B , but when the shaft  508  is rotated in the opening  512 , the cam protrusion  534  is rotated into contact with the groove  510 , thereby driving the bar  500  in an inward direction (i.e., into the receiver opening  520  to guide surfaces  550 ), thereby eliminating any loose horizontal fitment between the parts  500 ,  505 . 
     Furthermore, in some embodiments, the end portion of the bar  500  can have one or more tapered, sloped, or curved guide surfaces  540  that are driven into contact with the corresponding tapered, sloped, or curved guide surfaces  550  in the receiver opening  520 . The angled nature of these guide surfaces  540 ,  550  helps guide the bar  500  into a desired position relative to the receiver  505  and eliminates vertical loose fitment between the parts  500 ,  505 . Engaging guide surfaces such as surfaces  540  and  550  can therefore be referred to as “guide surfaces” herein because they can be used to guide the bar into the position shown in  FIGS.  5 C- 5 D  if the end of the bar  500  is inserted somewhat angularly askew or translationally off-centered. Additionally, the bar  500  can comprise a first connector axis and the receiver can comprise a second connector axis. Those two axes can be aligned and can become coaxial (e.g., aligned with axis  513 ) when a fastener (e.g.,  508 ) is installed and the guide surfaces  540 ,  550  are brought into face-to-face contact with each other (e.g., when both pairs of guide surfaces are face-to-face contacting each other and the respective abutting surfaces are parallel to each other). 
     Once an off-positioned bar  500  engages the guide surfaces  550  and is urged inward/toward an end surface  555  between the guide surfaces  550 , the bar  500  is drawn into the proper orientation as increased engagement of the guide surfaces (i.e., engagement of guide surfaces  540  with guide surfaces  550 ) gradually reduces the available space for the bar  500  to fit in the receiver opening  520 . This naturally causes the bar  500  to rotate or translate into the position in  FIGS.  5 C- 5 D  as it slides against the guide surfaces  550  and moves further into the opening  520 , effecting the desired fit and orientation of the bar  500  within the receiver opening  520 . 
     The cam protrusion  534  is one mechanism by which the inward force on the bar  500  can be applied. In some embodiments, bar  400  can similarly be urged into guide surfaces of the receiver opening  420  by the insertion of the shaft  408  into the opening  410 , as discussed above in connection with  FIG.  4   . Thus, features and elements from embodiments described herein can be combined with other features and elements described in connection with other embodiments. 
       FIGS.  6 A and  6 B  show example side section views of another kind of connection assembly. In this case, the shaft  608  extends into a groove  610  in the bar  600 , and the bar  600  has a notch  660  into which a rotatable tongue portion  654  of the shaft  608  can rotate. The rotatable tongue portion  654  can have a ramped surface  656  configured to engage an inner surface  665  of the notch  660  as the shaft  608  rotates. Thus, as shown in  FIG.  6 A , the shaft  608  can be rotatable between a first position in which the tongue portion  654  is positioned out of the notch  660  (or at least out of contact with the notch  660 ), and  FIG.  6 B  shows that the shaft  608  can be rotated to a second position in which the tongue portion  654  contacts the notch  660 . The inner surface  656  and/or inner surface  665  can be sloped, curved, or ramped in a manner that gradually drives the bar  600  inward (i.e., perpendicular to the axis of rotation of the shaft  508 /with guide surfaces  640  contacting guide surface(s)  650 ) as the shaft  608  rotates clockwise about its axis of rotation.  FIG.  6 B  also shows that the groove  610  moves relative to the shaft  608  as the shaft  608  it rotates because of the movement of the bar  600 . Accordingly, the groove  610  can have a dimension along the bar  600  that exceeds the diameter of the shaft  608  to accommodate translation of the bar  600  relative to the shaft  608  as the guide surfaces  640 / 650  move the bar  600 . 
       FIGS.  7 A- 7 B  show diagrammatic top views of additional connection assemblies that join an electronic device  702  and a stand  704 . In some embodiments, the electronic device can be element  704 , and the stand can be element  702 . A bar  700  extends away from the electronic device  702  and is positioned adjacent to a fixed post  705 . A second, translatable post  710  that is anchored to the stand  704  can be used to apply a clamping force to the bar  700 . Thus, in the embodiment of  FIG.  7 A , the bar  700  is clamped by its laterally-outward-facing surfaces  706  coming into contact with, and being frictionally held between, the fixed and translatable posts  705 ,  710 . In the embodiment of  FIG.  7 B , the bar  700  is clamped by its laterally-inward-facing surfaces  708  coming into contact with the posts  705 ,  710  and thereby being frictionally held in place against the those surfaces  708 . These schematic views illustrate how the bar  700  can be held in place without a fastener or shaft and with friction, rather than interference of parts, being the main force seating the bar  700  in place, wherein the friction is applied to side surfaces of the bar  700  rather than top and bottom surfaces (e.g., as in the embodiment of  FIGS.  3 A- 3 B ). 
       FIG.  8    illustrates a top section view of a connection assembly for a bar  800  that is connected to an electronic device  802  and a tilt hinge  809  that is connected to a lift arm  812 . In this embodiment, the bar  800  includes lateral openings  810  on opposite sides of the bar  800 , and each lateral opening  810  is threaded. The bar  800  is insertable into a receiver opening  820  in the tilt hinge  809 , as shown in the position of  FIG.  9   . When inserted, the lateral openings  810  can be centrally aligned with lateral openings  813  of the tilt hinge  809 , as indicated in  FIG.  8   . The lateral openings  810 ,  813  can have substantially equal diameters so that a shaft  808  can be installed on each side of the tilt hinge  809  with an end portion  834  fitting within each opening  810 ,  813 , as shown in  FIG.  9   . In this manner, contact between the end portion  834  and the openings  810 ,  813  can keep the bar  800  aligned with receiver barrel  840  in the tilt hinge  809 . In some embodiments, the bar  800  can extend from a mount adapter that is attachable to an electronic device (e.g.,  802 ), such as one of the embodiments of mount adapters disclosed in U.S. patent application Ser. No. 16/563,252, entitled “Display Support Arm Mount” and filed 6 Sep. 2019, the entire disclosure of which is hereby incorporated by reference. 
     The receiver barrel  840  and at least one arm barrel  842  (see  FIGS.  8  and  10   ) can be rotatable relative to each other about an axis of rotation  848 . See  FIG.  12    and its related description below. The lateral openings  813  and receiver opening  820  can be formed within the receiver barrel  840 . The receiver barrel  840  can also comprise a widened bore  844  (see  FIGS.  8  and  10   ) configured to receive each shaft  808 , wherein the widened bore  844  forms a shoulder  846  having a shoulder face on each side where the bore  844  transitions to the lateral opening  813 . A head portion can be positioned at the end of each shaft  808  and can be wider than the rest of the shaft  808 . The head portion can be turned using a tool or wrench to tighten or loosen the shaft  808  in the opening  810 . The head portion can include a recess, hex shape, or other manipulation surface configured to be engaged by a tool to rotate the shaft  808 . 
     The shoulder  846  can have an end profile that is circular with an open center (i.e., lateral opening  813 ). The arm barrel  842  can be rotated about the axis of rotation  848  extending centrally through the receiver barrel  840 . Thus, the arm barrel(s)  842  and the attached lift arm  812  can pivot about the axis of rotation  848  relative to the receiver barrel  840 . Meanwhile, the bar  800  is affixed to the receiver barrel  840  by the fastener shafts  808  and rotates synchronously with the receiver barrel  840 . In other words, the bar  800  can be a first connector having a first connector axis that extends longitudinally and centrally through the lateral openings  810 , the receiver barrel  840  can be a second connector having a second connector axis along axis of rotation  848 , and the first connector axis and the second connector axis can be aligned with each other when at least one shaft  808  is installed. The bar  800  and the receiver barrel  840  can be joined in this manner to move as a single unit that can be referred to as a pivotable arm since it pivots relative to the arm barrel(s)  842  about axis of rotation  848 . 
     The rotation of the receiver barrel  840  and the arm barrel(s)  842  can be limited or resisted due to an optional spring (e.g., a torsion spring)  850  and/or an optional set of friction disks  852  positioned around opposite ends of the receiver barrel  840 . See  FIGS.  8  and  10   . The spring  850  can have a first end attached to (e.g., friction-fitted, welded, or fastened to) the receiver barrel  840  and a second end attached to (e.g., friction-fitted, welded, or fastened to) an arm barrel  842 . In one embodiment, the spring  850  may include one or more coils having a first diameter coupled with an end of the receiver barrel  840 , and one or more coils having a second diameter (e.g., a larger diameter) coupled with the arm barrel  842 . The attachment between these parts  850 ,  840 ,  842  can cause the potential energy of the spring  850  to increase or decrease as there is relative rotation between the barrels  840 ,  842  about the axis of rotation  848 . Accordingly, the spring  850  can be used to bias the rotation of the barrels  840 ,  842  toward a desired “home” or “default” position where the potential energy of the spring  850  is the lowest. In some embodiments, this position is a horizontal position, as shown in  FIG.  1 C . 
     The spring  850  can be configured to assist the user in adjusting the tilt of the electronic device  802  when the bottom of the device is tilted forward (i.e., the movement of the electronic device  102  from the position of  FIG.  1 B  to the position shown in  FIG.  1 C ) by applying a torque to the barrels  840 ,  842  that helps the device rotate in that direction at the tilt hinge  809 . The spring  850  also can resist rotation of the electronic device  802  when the device is rotated in the opposite direction (e.g., the direction shown by the movement of the electronic device from the position of  FIG.  1 C  to the position of  FIG.  1 B ) by storing potential energy and applying a resisting torque to the tilt hinge  809 . In this manner, the spring  850  can improve the ergonomics of the stand (e.g.,  104 ) by making the electronic device require substantially similar (e.g., equal) torque to pivot at the tilt hinge  809  whether it is tilted in a forward or backward direction (i.e., in a clockwise or counterclockwise direction as viewed from a lateral side thereof). The resistance and assistance of the spring  850  can be especially beneficial in embodiments where the center of gravity of the electronic device  102  is positioned vertically higher than the tilt hinge  809  (e.g., at the vertical level of joint  114  in  FIG.  1 C ) so that the electronic device  102  does not over-rotate due to the center of gravity passing over the tilt hinge  809 . 
     The friction disks  852  can be used to apply frictional resistance to the relative movement of the barrels  840 ,  842 . The resistance can improve ergonomics by making the rotation of the barrels  840 ,  842  require more torque in both directions (i.e., tilting forward and backward). The increased torque can help limit inadvertent tilting movements of the electronic device (e.g., when the device is bumped or the stand is shaken and the device&#39;s rotated position may drift). The friction disks  852  can have adjustable compression or tension so that the friction applied by the disks is adjustable to a predetermined level. In combination with the spring  850 , the friction disks  852  can be tuned so that the user only needs to provide a single, predetermined, substantially equal torque for tilting the device in either direction. 
     As discussed above, a bar may wobble or have loose fitment with a receiver opening if it is not properly constrained. The connection system of  FIGS.  8 - 11    can be used to constrain movement of the bar relative to the receiver opening  820  in at least five (and potentially six) degrees of freedom. To do so, the receiver opening  820  can comprise a pair of curved protrusions  1100 , as shown in  FIG.  11    (and also seen in part in  FIGS.  8  and  10   ), that are configured to engage a curved end surface  1102  of an end portion  1104  of the bar  800 . In other words, the receiver opening  820  can include two guide surfaces (on protrusions  1100 ) configured to engage two guide surfaces (i.e., opposite sides of  1102 ) of the bar  800 . In some embodiments, the guide surfaces can be formed as part of the inner walls of the opening  820  rather than being part of protrusions  1100 . 
     In order to ensure a tight fit between the pairs of guide surfaces, one shaft  808 - a  can be installed with its threaded end portion  834  configured to engage the threads of a lateral opening  810  of the bar  800  while being seated in contact with the shoulder  846  of the widened bore  844  of the receiver barrel  840 , as shown in  FIG.  9   . The shaft  808  can comprise its own widened portion  836  (i.e., a shank) to form a shoulder  837  of its own, as shown in  FIGS.  9  and  10   . In this manner, the shoulders  837 ,  846  are pulled and held into contact with each other as the threads at portion  834  are tightened. Simultaneously, the end portion  1104  of the bar  800  is pulled between the curved protrusions  1100  and into tight contact with them by the threads. The bar  800  is thereby secured to the receiver barrel  840  and limited from movement relative to the receiver barrel  840  such as translation along the x-, y-, or z-axes in  FIGS.  9  and  11   . The contact at the curved protrusions  1100  also prevents rotation of the bar  800  relative to the barrel  840  about at least the x- and z-axes. A properly tightened fit and sizing of the shaft end portion  834  diameter and the lateral opening  813  of the receiver barrel  840  can also prevent rotation of the bar  800  relative to the barrel  840  about the y-axis. The outer curved surfaces of the end portion  1104  can be referred to as guide surfaces of the bar  800 , and the curved protrusions  1100  can be referred to as guide surfaces of the receiver barrel  840 . The outer curved surfaces of the end portion  1104  are curved tapering surfaces that gradually transition the width of the end portion  1104  from a maximum thickness to a narrower thickness that engages the corresponding tapering shape of the curved protrusions  1100 . 
     In some embodiments, the tilt hinge  809  can comprise guide surfaces that are non-orthogonally angled or tapered (similar to a “V”-shape) against which the curved (or, alternatively, similarly non-orthogonal, tapered, “V”-shaped) surfaces of the bar  800  can come into contact. Additionally, although the protrusions  1100  have convex surfaces that come into contact with the bar  800 , in some embodiments, protrusions  1100  can be used that have flat tapering surfaces or concave surfaces to receive the bar  800 . The movement of the bar  800  in the opening  820  (e.g., along the positive x-axis in  FIG.  11   ), can enable the guide surfaces to abut and slide against each other until they reach a position where the mechanical interference caused by contact between the guide surfaces prevents any further movement of the bar  800  relative to the opening  820 . The engagement of the guide surfaces on elements  1100  and  1102  causes clamping of the bar  800  similar to the schematic clamping illustrated in  FIGS.  7 A and  7 B  and the guide surface contact of  FIGS.  5 D and  6 B . 
     In some embodiments, the lateral opening  810  receiving the shaft  808 - a  is configured to have a length or positioning that allows the shaft  808 - a  to be tightened in the opening  810  without bottoming out at the innermost end  858  of the opening  810 , as shown by gap  860  in  FIG.  9   . The gap  860  can ensure that the end portion  834  is not prevented from tightening sufficient to cause abutment between the shoulders  837 ,  846  and the guide surfaces on elements  1100  and  1102 . This feature ensures that the innermost end  858  and shaft  808 - a  do not need to be perfectly sized and manufactured. Otherwise, the shaft  808 - a  could be too long relative to the opening  810  to tighten the abutting surfaces due to interference contact with the innermost end  858 . As a result, the gap  860  reduces manufacturing costs and makes proper hinge assembly simpler. 
     The opposite side of the tilt hinge  809  can comprise a similar shaft  808 - b  that is installed into the opposite lateral opening  810  of the bar  800  so that it bottoms out and comes into contact with the inner end wall of the opening  810 . This shaft  808 - b  can effectively act as a cantilever or pin extending from the bar  800  without constraining the movement of the bar  800  relative to the receiver opening  820 . However, both shafts  808  can have the same dimensions so as to be interchangeable and therefore easier for a user to install and adjust. In other words, the user does not need to keep track of which fastener fits in each side of the tilt hinge  809 . The manufacturer also only needs to make two of one part rather than two unique parts, thereby saving production costs due to economies of scale. In order for one opening  810  to have the gap  860  and the other to lack the gap  860 , the openings  810  can have different depths or the receiver barrel  840  can have different thicknesses between the receiver opening  820  and shoulders (e.g.,  837 ) in each side&#39;s bore (e.g.,  844 ). 
       FIG.  12    illustrates a side section view of the tilt hinge  809  as taken through section lines  12 - 12  shown in  FIG.  9   . As shown, the bar  800  and receiver barrel  840  can be configured to rotate relative to the arm barrel  842 . The arm barrel  842  can comprise an internal opening  1200  within which the bar  800  and receiver barrel  840  rotate about the axis of rotation  848 . The bar  800  is shown in broken lines at an upward rotated position  1202 . The opening  1200  can have rear surfaces  1204 ,  1206  into which the top and bottom surfaces of the bar  800  can move into contact to define the limits of the rotation of the bar  800  relative to the arm barrel  842 . Front surfaces  1208 ,  1210  can be arranged so that the bar  800  never comes into contact with them (i.e., there is a gap or clearance between the front surfaces  1208 ,  1210 ), even when the bar  800  is at its extreme tilted positions about the axis of rotation  848 . Thus, when the top of the bar  800  engages the rear top surface  1206  and therefore cannot rotate any further, the bar  800  may be spaced away from or out of contact with the front bottom surface  1208 . Similarly, when the bottom of the bar  800  engages the rear bottom surface  1204 , the top of the bar  800  can be out of contact with the front top surface  1210 . This configuration can reduce the chance that the bar  800  will pinch and compress objects positioned between the bar  800  and the opening  1200  when accessed from the front side.  FIG.  12    also shows an optional configuration of the arm barrel  842  wherein a rear wall  1212  is included on the arm barrel  842 . The rear wall  1212  can prevent intrusion of objects into the opening  1200  from the rear side of the hinge  809 . 
       FIGS.  13 A- 13 B  illustrate diagrammatic side views of a support system  1300  for an electronic device. The support system  1300  can be implemented as part of support system  100 , such as for the lift arm  112  and related joints  110 ,  114  and connecting devices  108  and  118 . The support system  1300  can include an arm assembly  1302  that extends between and joins the electronic device  1304  to a stand  1306  (or other ground surface/support surface). The arm assembly  1302  includes a housing  1301  containing support mechanisms that manage and support the vertical position of the electronic device  1304  relative to the stand  1306 . 
     The arm assembly  1302  comprises a device attachment structure  1308  that is secured to the electronic device  1304  and is pivotable relative to a tilt connector  1310  at a tilt hinge  1309 . In some embodiments, the tilt hinge  1309  has its pivot axis coaxial with a center point between attachment points  1318 ,  1322  on the tilt connector  1310 . Tilt hinges can comprise a configuration described in connection with  FIGS.  2 - 12    and are only shown schematically in  FIG.  13 A  and beyond. In some embodiments, the device attachment structure  1308  and the tilt connector  1310  can be formed as a single device attachment structure  1308  (without a tilt hinge  1309 ) or can be collectively referred to as a device attachment structure. 
     A support structure  1312  is coupled to the stand  1306 . In some embodiments, the support structure  1312  is a single-piece, rigid structure connected to the stand  1306  or is an integral part of the stand. The support structure  1312  can also comprise a tilt hinge (e.g., like those described in  FIGS.  2 - 12   ) to give additional articulation and range of motion to the system  1300 , in which case the support structure  1312  can be pivotable relative to a stand base connector (e.g.,  118 ). 
     A first arm  1314  and a second arm  1316  are coupled to the tilt connector  1310  and to the support structure  1312 . The tilt connector  1310  includes first and second attachment points  1318  and  1322 , respectively, and the support structure  1312  includes third and fourth attachment points  1320  and  1324 , respectively. The first and second arms  1314 ,  1316  are pivotally connected to the tilt connector  1310  and support structure  1312  at the attachment points as shown in  FIGS.  13 A- 13 B . The lengths of the arms  1314 ,  1316  are equal, and the distances between the first/second and third/fourth attachment points are equal, so the attachment points form corners of a parallelogram-shaped pivot profile. This configuration of pivot points and connecting parts is referred to as a “four-bar” linkage or mechanism. 
     As shown in  FIG.  13 A , the arm assembly  1302  can have a first (e.g., horizontal) position wherein the tilt connector  1310  and support structure  1312  are parallel to each other and vertical, thereby forming a rectangle with the attachment points.  FIG.  13 B  shows that the arm assembly  1302  can be moved to a position where the electronic device  1304  is lowered downward, but the tilt connector  1310  and support structure  1312  remain parallel to each other and vertical. In this manner, the adjustment of the arm assembly  1302  beneficially does not automatically change the tilted orientation of the electronic device  1304 , and it only translates up or down (along an arc-shaped path, so there is small horizontal translation as well) as the arm assembly  1302  is adjusted. 
     The housing  1301  has two end openings  1326 ,  1328  through which the device attachment structure  1308  (and/or tilt connector  1310 ) and support structure  1312  respectively extend. In order to prevent ingress of objects and debris into the housing  1301 , sheaths  1330 ,  1332  can be installed at each end of the housing  1301  around the four-bar mechanism. The sheaths  1330 ,  1332  can have substantially circular or partially-circular shapes with sufficient size to completely cover the inside perimeters of the openings  1326 ,  1328  at any rotated position of the arm assembly  1302  and/or the tilt hinge  1309 . In order to do so, the front sheath  1330  at the tilt hinge  1309  is configured to cover a greater range of angles (e.g., by having a circular, 360-degree side profile) because the full combined range of movement of the arm assembly  1302  and the tilt hinge  1309  can cause exposure of over 180 degrees of the circumference of the sheath  1330 . The rear sheath  1332  can have a substantially C-shaped or have a 180-degree-coverage/semicircular side profile due to only needing to cover the opening  1328  during rotation of the four-bar mechanism at the support structure  1312 .  FIGS.  13 A- 13 B  show how the sheaths  1330 ,  1332  can have portions radially overlapping the housing  1301  (relative to the center points between attachment points  1318 ,  1320 ,  1322 ,  1324 ) at multiple angles of rotation of the arm assembly  1302 . 
     A counterbalance mechanism can be used in conjunction with the four-bar mechanism to help prevent the weight of the electronic device  1304  from causing downward sagging relative to the stand  1306  and to make the amount of force required to raise the electronic device  1304  by rotating the arm assembly  1302  more equal to the amount of force needed to lower the electronic device  1304  by rotating the arm assembly  1302 . The counterbalance mechanism can include at least one spring  1334  positioned within a retainer  1336  at a position between the first and second arms  1314 ,  1316  and between the tilt connector  1310  and the support structure  1312 . In some embodiments, a retainer bar  1338  can extend between the arms  1314 ,  1316  with pivot points attached to the arms  1314 ,  1316  along a line parallel to the ends of the four-bar mechanism, as shown in  FIGS.  13 A- 13 B . The retainer  1336  can then be pivotally connected to the retainer bar  1338  with the spring  1334  inside. In some configurations, the retainer  1336  does not constrain the sides of the spring  1334  and only constrains one end of the spring  1334  with a spring retention portion  1340 . 
     The retainer  1336  can have a spring retention portion  1340  (e.g., a ledge, ridge, or protrusion) configured to engage and contact an end of the spring  1334 . Thus, the spring retention portion  1340  can prevent the spring  1334  from separating from (e.g., pulling out or falling out of) the retainer  1336 . In some embodiments, the spring retention portion  1340  can be a part providing mechanical interference to movement of the end of the spring  1334  relative to the retainer  1336 . In some embodiments, the spring retention portion  1340  can comprise a fastener, weld, or other attachment feature that joins the end of the spring  1334  to the retainer  1336  and thereby prevents the end of the spring  1334  from moving relative to the retainer  1336 . 
     The counterbalance mechanism can also comprise a rod  1342  that is pivotally connected to the first or second arm  1314 ,  1316  at a rod pivot point  1344 . The opposite end of the rod  1342  can extend through or around the spring  1334  and can be coupled to an end of the spring  1334  positioned on the spring  1334  opposite the rod pivot point  1344 . As shown in  FIGS.  13 A- 13 B , the rod  1342  can have a flared end that forms a platform against which the end of the spring  1334  can abut and contact. In some embodiments, the end of the rod  1342  can be affixed or attached to the end of the spring  1334 , such as by being fastened or welded in a manner that links the movement of the rod to the movement of the end of the spring  1334 . 
     As the four-bar mechanism rotates, the rod  1342  of the counterbalance mechanism also rotates due to movement of the first arm  1314  and movement of the retainer  1336  (via movement of retainer bar  1338 ). The rod  1342  is not parallel to one of the sides of the four-bar mechanism and does not have its spring-coupled end coupled to the other arm (i.e.,  1316 ), so the rod  1342  therefore does not rotate at the same angular velocity as the arm to which it is connected (i.e.,  1314 ). Accordingly, the angle between the rod  1342  and the arm  1314  decreases as the first arm  1314  pivots about third attachment point  1320 , as shown by comparing their relative angles A 1  and A 2  in  FIGS.  13 A- 13 B . 
     Decreasing angle A (e.g., going from A 1  to A 2 ) causes the rod  1342  to compress the spring  1334  within the retainer  1336 . This is due to the coupling of the end of the rod  1342  with the spring  1334  that applies a compressive force to the spring  1334  (directed along the length of the rod  1342  toward the rod pivot point  1344 ) and due to the coupling of the spring retention portion  1340  and the spring  1334  preventing the spring  1334  from being pulled out of the retainer  1336  (i.e., providing a force resisting the compressive force of the rod  1342 ). If angle A increases (e.g., going from A 2  to A 1 ), the spring  1334  releases energy as it presses against the spring retention portion  1340  and the end of the rod  1342 . The spring  1334  can therefore store potential energy as the electronic device  1304  moves downward and can release potential energy as the device  1304  moves upward, thereby assisting the user in raising the device and slowing the descent of the device when it moves downward. Friction disks can be added to the attachment points  1318 ,  1320 ,  1322 ,  1324  to add additional frictional resistance to movement of the four-bar mechanism so that the arm assembly  1302  has a firm and predictable feel. 
     The positioning of the rod pivot point  1344  and the retainer bar  1338  relative to each other and relative the arms  1314 ,  1316  can therefore define the rate at which the spring  1334  is compressed (or decompressed) by the rotation of the arm assembly  1302 . As such, the spring, retainer, and rod can be designed to cause a predetermined amount of potential energy to be stored or released as the arm assembly  1302  is rotated. For example, these components can be designed based on the mass of the electronic device and the mass of the rest of the arm assembly  1302  to make the storage of energy in the spring  1334  closely follow the loss of potential energy in the device  1304  (and arm), and vice versa. A large variety of springs can be used for the spring  1334 , including compression springs, leaf springs, multiple springs used in series or in parallel, springs with a linear spring constant, springs with a non-liner spring constant, and combinations thereof. 
       FIGS.  14 A- 14 C  show side views of another embodiment of a lift system  1400  with an arm assembly  1402  connectable to an electronic device  1304  and stand  1306 .  FIG.  14 A  shows a side view of a device attachment structure  1404 , a support structure  1406 , and an arm-housing  1408  that is pivotally connected to the device attachment structure  1404  and the support structure  1406  at pivot joints  1410  and  1412 , respectively. The device attachment structure  1404  can have a tilt joint  1411  offset from the pivot joint  1410  of the arm-housing  1408  or can have a tilt joint at pivot joint  1410  that allows the electronic device  1304  to pivot relative to the rest of the device attachment structure  1404 . 
     The arm-housing  1408  can function similar to arm  1314  or arm  1316  by providing a rigid link between the pivot joints  1410 ,  1412 . The arm-housing  1408  can also be configured to enclose and cover at least one side of the device attachment structure  1404  and the support structure  1406 . In  FIG.  14 A , the arm-housing  1408  covers their back sides. The arm-housing  1408  can also extend over and around the device attachment structure  1404  and the support structure  1406  and can therefore serve a purpose similar to the housing  1301  by covering the top and bottom surfaces of the device attachment structure  1404  and the support structure  1406 . End openings  1414 ,  1416  can be formed in the arm-housing  1408  to allow the device attachment structure  1404  and the support structure  1406  to protrude from the enclosure. 
     As shown in  FIG.  14 B , the system  1400  can further include a belt  1418  extending between and wrapped around the device attachment structure  1404  and the support structure  1406 . The belt  1418  can comprise a series of engagement features (e.g., teeth or ridges) that extend radially inward relative to the pivot joints  1410 ,  1412  and the axis linking the pivot joints  1410 ,  1412 . The engagement features can be configured to engage grooves, gear teeth, or recesses extending around the outer circumferences of the device attachment structure  1404  and the support structure  1406 . The engagement features of the belt  1418 , device attachment structure  1404 , and support structure  1406  can thereby prevent the belt  1418  from sliding and make the belt  1418  incapable of sliding while in contact with the corresponding engagement features on the outer surfaces of the device attachment structure  1404  and the support structure  1406 . 
     The belt  1418  is configured to link the rotation of the device attachment structure  1404  and the support structure  1406  as they respectively rotate about the pivot joints  1410 ,  1412 . Accordingly, as shown in  FIGS.  14 B and  14 C , the device attachment structure  1404  and the support structure  1406  rotate at the same rate as the arm-housing  1408 , thereby ensuring that the electronic device  1304  and the stand  1306  maintain their angular positions relative to each other, similar to the operation of the four-bar mechanism. For instance, these figures show that the device  1304  remains vertical and parallel to the vertical surface of the stand  1306  as the system  1400  rotates about pivot joint  1412 . The belt  1418  contributes to this behavior by acting in tension between the device attachment structure  1404  and the support structure  1406 . 
     As the device attachment structure  1404  or the support structure  1406  rotates, the other structure also rotates due to being acted upon (e.g., pulled) by the belt  1418 . As the system  1400  moves the electronic device  1304  downward, tension in the top portion of the belt  1418 - a  rotates the device attachment structure  1404  clockwise (i.e., in direction  1420  about joint  1410 ). Tension in the bottom portion  1418 - b  can also rotate the device attachment structure  1404  clockwise. As the system  1400  moves the device upward, tension in the bottom section of the belt  1418 - b  rotates device attachment structure  1404  counterclockwise about joint  1410 . Tension in the top portion  1418 - a  can assist as well. As a result, the belt  1418  can flexibly provide a non-sliding link between the device attachment structure  1404  and the support structure  1406 , wherein the belt  1418  applies tension between the top side of the device attachment structure  1404  and the support structure  1406  and/or the bottom sides thereof depending on the direction of movement of the lift system  1400 . 
     Additionally, the points between which tension is applied to the belt  1418  can change as the lift system  1400  is operated. In the position of  FIG.  14 B , the belt  1418  is under tension between points B 1  and B 2  on the belt, but in the position of  FIG.  14 C , rotation of the device attachment structure  1404  and the support structure  1406  (and their non-sliding link to the belt  1418 ) causes the tension to be between points B 3  and B 4 , which are each positioned on the belt  1418  closer to the electronic device  1304  (and positioned counterclockwise around the circumferences of the structures  1404 ,  1406 ) than points B 1  and B 2 , respectively. Accordingly, the operation of the lift system  1400  can include a set of moving tension points on the belt  1418 . The moving tension points (e.g., points B 1  through B 4 ) can move along one direction along the length of the belt  1418 , as shown by  FIGS.  14 B and  14 C  where points B 1  through B 4  move along the top portion  1418 - a  of the belt toward the electronic device  1304 , as the lift system  1400  moves in one direction (e.g., downward). The tension limits can move in the opposite direction as the lift system  1400  moves in the opposite direction (e.g., upward, as shown in movement from the position of  FIG.  14 C  to the position of  FIG.  14 B ). Similar movement of the tension limits would continue (i.e., even further away from the electronic device  1304  on top of the device attachment structure  1404  and the support structure  1406 ) if the electronic device  1304  moves to a raised position relative to  FIG.  14 B . 
     The belt  1418  can comprise a strap including rubber, fabric, rope, string, fiber, composite, or similar flexible material configured to reshape itself to the surfaces of the device attachment structure  1404  and the support structure  1406  as it wraps and unwraps their outer circumferences. In some embodiments, the belt  1418  can comprise another similar structure, such as a chain that is configured to engage teeth or grooves on the device attachment structure  1404  and the support structure  1406 . 
     In some embodiments, the arm-housing  1408  can further comprise tensioning protrusions, pins, or rollers (not shown) that are configured to keep the belt  1418  in tension and to reduce blowback and slack between the belt  1418  and the device attachment structure  1404  and the support structure  1406 . For instance, the protrusions or rollers can apply inward forces  1422  as shown in  FIG.  14 C . 
     Furthermore, as shown in  FIGS.  14 B and  14 C , the lift system  1400  can include a counterbalance mechanism  1424 . The counterbalance mechanism  1424  can comprise a retainer, spring, and rod as described above in connection with  FIGS.  13 A- 13 B  and can thereby store and release potential energy corresponding to the loss or gain of potential energy of the electronic device  1304  and lift system  1400 . The counterbalance mechanism  1424  can have connections to pivot point  1426  attached to the arm-housing  1408  and pivot point  1428  attached to the support structure  1406 . The system  1400  can also comprise sheaths such as  1330  and  1332  (not shown in  FIGS.  14 A- 14 C ). 
     Pivot point  1426  is shown positioned at the opposite end of the retainer as compared to the opening through which the rod of the counterbalance mechanism  1424 . In some embodiments, the pivot point  1426  can be positioned at the opening in the retainer or along the length between the ends of the retainer, such as the pivot point shown in  FIGS.  13 A- 13 B . Furthermore, in some embodiments, the spring can be an extension spring, wherein the spring is configured to store energy by extension of its length. For instance, the rod can be connected to the end of the extension spring, and the retainer can be connected to the opposite end of the extension spring. Rotation of the link arm can then rotate the rod in a manner extending the spring, depending on the location of the rod pivot point and the pivot point  1426  of the retainer, as will be understood by those having skill in the art and hindsight benefit of the present disclosure. 
       FIGS.  15 A and  15 B  show yet another embodiment of a lift system  1500 . This embodiment comprises structures that operate similar to the system of  FIGS.  13 A- 13 B . However, rather than having rigid sheaths  1330 ,  1332 , the system  1500  includes flexible sheaths  1530 ,  1532  that cover the end openings  1526 ,  1528  of the housing  1501  and conceal internal parts. The flexible sheaths  1530 ,  1532  can each comprise a convex portion  1534  positioned between two concave portions  1536 ,  1538 . Alternatively, the convex portion  1534  can be referred to as a central portion, and the concave portions  1536 ,  1538  can be referred to as end portions. A device attachment structure  1540  extends through the center of the front flexible sheath  1530 , and a support structure  1542  extends through the center of the rear flexible sheath  1532 . In some embodiments, the sheaths  1530 ,  1532  can be integrally formed with or attached to the device attachment structure  1540  and the support structure  1542 , respectively. 
     In a first position wherein the housing  1501  is horizontal and extends perpendicular to the electronic device  1304  and the stand  1306 , as shown in  FIG.  15 A , the convex portion  1534  and concave portions  1536 ,  1538  are vertically symmetrical (i.e., mirrored in shape across a horizontal axis), and the concave portions  1536 ,  1538  extend into the internal cavity of the housing  1501  to equal depths relative to the opening  1526 . The convex portion  1534  covers the entire end opening  1526 , and the end tips of the concave portions  1536 ,  1538  contact the inner surface of the housing  1501 . In a second position wherein the housing  1501  is rotated and angled relative to the electronic device  1304  and stand  1306 , as shown in  FIG.  15 B , the front and rear flexible sheaths  1530 ,  1532  deform to accommodate the movement of the housing  1501 . Specifically, the front flexible sheath  1530  has its upper concave portion  1536  slide to move deeper into the housing  1501  relative to the opening  1526 , and its lower concave portion  1538  slides relative to the housing  1501  to a position closer to the opening  1526 . The opposite is true for the rear flexible sheath  1532 , as shown in  FIG.  15 B . Thus, as the housing  1501  (and the support mechanisms within the housing  1501 ) rotate and move, the flexible sheaths  1530 ,  1532  can deform to adapt to the movements. The lengths of the front and rear flexible sheaths  1530 ,  1532  can be designed to ensure that the tips at the ends of the concave portions  1536 ,  1538  slide along the internal surface parallel to the longitudinal axis of the housing  1501  and do not come out of the openings  1526 ,  1528  even when the device attachment structure  1540  and support structure  1542  are at their most extreme rotated positions relative to the housing  1501 . 
     In some cases, the flexible sheaths  1530 ,  1532  can slide along the inner surface of the housing  1501 , thereby sweeping debris or other objects out of the space between the housing  1501  and the sheaths  1530 ,  1532  and preventing material from passing into the housing  1501  internal to the sheaths  1530 ,  1532 . In some embodiments, the flexible sheaths  1530 ,  1532  can engage the inner lip of their respective opening  1526  or  1528  and can remain in contact with the inner lip to block out intruding objects. 
     In some embodiments, the flexible sheaths  1530 ,  1532  apply outward pressure to the housing  1501 , as indicated by arrows D that are oriented perpendicular to a longitudinal axis extending across the housing  1501 . The flexible sheaths  1530 ,  1532  can therefore maintain contact with the inner surface of the housing  1501  as they slide along the inner surface of the housing  1501  due to rotation of the housing  1501 . The contact with the inner surface can help preserve a seal and barrier that prevents ingress of debris or objects into the housing  1501  between the housing  1501  and the flexible sheaths  1530 ,  1532 . 
     The flexible sheaths  1530 ,  1532  can each comprise a single piece of flexible material such as a sheet of metal, plastic, composite, rubber, or similar material configured to resiliently bend and unbend. In some embodiments, the sheaths  1530 ,  1532  can include a set of bendably linked or hinge-linked segments that can bend or fold to adapt to the movement of the housing  1501  relative to the device attachment structure  1540  and the support structure  1542 . Thus, some configurations can be referred to as having a “garage door” arrangement of rigid yet hinged parts. In some embodiments, ends of the sheaths  1530 ,  1532  can be guided by rails, tracks or other support surfaces that ensure the ends of the sheaths do not undesirably fall or slip into interference or contact with the arm assembly or counterbalance mechanisms within the housing  1501 . 
     Using the flexible sheaths  1530 ,  1532  can advantageously leave the interior of the housing  1501  substantially open, thereby allowing the arm support assembly and counterbalance mechanisms to use that space. A device maker can use larger, longer parts within the housing  1501  or can reduce the length of the arm due to the parts not needing a sheath (e.g.,  1330 ) that extends radially inward relative to the longitudinal axis of the housing (e.g.,  1301 ). This can save costs, simplify manufacturing and assembly, and reduce weight. 
     Another aspect of the disclosure relates to systems and methods for connecting a support stand to an electronic device, wherein the support stand includes a protrusion or bar that is configured to engage a receiver or lock mechanism of the electronic device.  FIGS.  16 A- 19    illustrate various views of an embodiment of a system wherein a protrusion  1600  of a support stand  1602  is securely connectable to an electronic device  1604 . The device  1604  can include a housing  1606  with an opening  1608  for receiving the protrusion  1600  and a lock mechanism  1610  (i.e., a latch) positioned internal to the opening  1608  (i.e., within a cavity  1612  formed within the device  1602 ).  FIG.  16 A  shows a top view of the interface between the protrusion  1600  and the electronic device  1604  with the protrusion  1600  and stand  1602  positioned spaced away from the opening  1608  (i.e., in an un-connected position).  FIG.  16 B  shows a side section view as taken through section lines  16 B- 16 B in  FIG.  16 A .  FIG.  17 A  shows a top view with the protrusion  1600  in a second position relative to the housing  1606 , wherein the protrusion  1600  is inserted into the opening  1608  but not locked in place by the lock mechanism  1610 .  FIG.  17 B  is a side section view as taken through section lines  17 B- 17 B in  FIG.  17 A .  FIG.  17 C  is a side section view of the interface as taken through section lines  17 C- 17 C in  FIG.  17 A .  FIG.  18    shows a side section view at a position similar to the position of  FIG.  17 B  but with the lock mechanism  1610  locking the protrusion  1600  into position within the housing  1606 .  FIG.  19    shows a similar side section view with the lock mechanism  1610  in a position configured to eject the protrusion  1600  from the housing  1606 . 
     The protrusion  1600  can comprise a narrow portion  1614  and a wide portion  1616 , as shown in  FIGS.  16 A and  16 B . These portions  1614 ,  1616  can form a shoulder surface  1618  at their convergence that faces substantially outward relative to the electronic device  1604 . The lock mechanism  1610  can include a passage  1620  through which at least the wide portion  1616  of the protrusion  1600  is inserted as the protrusion is moved from an external position relative to the lock mechanism  1610  ( FIGS.  16 A and  16 B ) and an inserted, internal position ( FIGS.  17 A and  17 B ). The protrusion  1600  can be inserted into the lock mechanism  1610  to a sufficient depth that the shoulder surface  1618  is fully positioned through the passage  1620 . 
     With the protrusion  1600  in the position shown in  FIG.  17 B , the lock mechanism  1610  can be operated (e.g., via adjustment mechanism/screw  1622 ) to translate downward and to move the passage  1620  to a position where the protrusion is no longer retractable out of the passage  1620  or opening  1608  due to mechanical interference contact between the shoulder surface  1618  and a front-facing surface  1624 , as shown in  FIG.  18   . The lock mechanism  1610  is capable of moving downward in this manner because the rotation of the adjustment mechanism  1622  drives threads on the lock mechanism  1610  to translate the lock mechanism  1610  along the axis of rotation of the adjustment mechanism  1622 . The lock mechanism  1610  moves from a position vertically offset from the wide portion  1616  of the protrusion  1600 , as shown in  FIGS.  16 B and  17 B , into a position obstructing the wide portion  1616 , as shown in  FIG.  18   . The adjustment mechanism  1622  can be positioned extending through a bottom surface of the housing  1606 , a lateral side surface of the housing, or a top surface of the housing. 
     Additionally, the front-facing surface  1624  of the lock mechanism  1610  can have a ramped or sloped surface that is closer to the housing  1606  at the end nearest to the protrusion  1600  and is farther from the housing  1606  above that end. Thus, as the lock mechanism  1610  moves downward, it can come into contact with the shoulder surface  1618  and can draw the shoulder surface  1618  inward (i.e., through the opening  1608  and deeper into the electronic device, perpendicular to the direction of movement of the lock mechanism  1610 ), thereby reducing or eliminating slop or wobble between the protrusion and the lock mechanism  1610 . Downward movement of the lock mechanism  1610  can proportionally drive additional inward movement of the protrusion  1600  until any gaps are eliminated. 
     Furthermore, as shown in  FIG.  17 C , the protrusion  1600  can comprise guide surfaces  1626 ,  1628  that come into contact with guide surfaces  1630 ,  1632  in an opening  1633  of a central block  1634  within the cavity  1612 . Thus, progressive inward movement of the protrusion  1600  can cause the guide surfaces to slide against each other to orient the protrusion  1600  to a desired position and angle relative to the central block  1634  in the housing  1606 , similar to other guide surfaces disclosed herein. The contact between guide surfaces, and their sloped, receding ramp orientation, can prevent movement of the protrusion  1600  in six degrees of freedom relative to the block  1634 . The block  1634  can remain stationary relative to the housing  1606  or can be built into or formed as part of the housing  1606 . 
     The adjustment mechanism  1622  can also be operated in the other direction (e.g., rotated about its axis of rotation in an opposite direction as compared to the direction driven in  FIG.  18   ) to move the lock mechanism  1610  upward, as shown in  FIG.  19   . Moving the lock mechanism upward  1610  moves the front-facing surface  1624  out of the way of the shoulder surface  1618  and thereby permits the protrusion  1600  to move out of the passage  1620  and opening  1608  again. 
     Additionally, if the lock mechanism  1610  is moved sufficiently far enough upward, such as to the position shown in  FIG.  19   , a rear-facing surface  1636  (i.e., an ejection surface) of the lock mechanism  1610  can be driven up against the wide portion  1616  of the protrusion  1600  and can thereby apply a force to the protrusion  1600  that pushes it out of the opening  1608  (i.e., in a direction substantially perpendicular to the direction of movement of the lock mechanism  1610 ). In some embodiments, the front-facing end of the wide portion  1616  can have a sloped or ramped surface configured to engage the rear-facing surface  1636  to facilitate smooth sliding of the protrusion  1600  along the rear-facing surface  1636  as the protrusion  1600  is ejected. The rear-facing surface can also be oriented non-orthogonally relative to a longitudinal axis of the protrusion  1600  so that as it moves, the ejecting force it applies to the protrusion  1600  increases. The passage  1620  can also have a vertical dimension that exceeds the vertical height of the protrusion  1600  so that there is sufficient clearance for the protrusion  1600  to remain in the passage  1620  while the lock mechanism  1610  moves upward to eject the protrusion, as shown in  FIG.  17 B  (showing the passage  1620  having extra space below the protrusion  1600 ) and  FIG.  19    (showing the passage  1620  having extra space above the protrusion  1600 ). 
     Thus, the system of  FIGS.  16 A- 19    can be used to provide a rigid, reversible link between a protrusion of a stand and a lock within an electronic device. Additionally, the positioning of the external devices can be reversed. In other words, the stand  1602  can be an electronic device, and the electronic device  1604  can be a stand or other attachment base. 
     Various other kinds of adjustment mechanisms can be used in addition to, or in place of, the screw-type adjustment mechanism  1622 . For example, as shown in  FIG.  20   , the vertical translation of a lock mechanism  2010  can be caused by a pivoting lever  2022  having an end  2024  attached to or abutting the lock mechanism  2010 . Downward rotation of the lever  2022  (on the outside of the housing  2006 ) can drive the lock mechanism  2010  upward, and upward rotation of the lever  2022  (on the outside of the housing  2006 ) can drive the lock mechanism  2010  downward. Implementation of a lever  2022  can eliminate the need for a tool to operate the adjustment mechanism and can change the amount of force and torque required as compared to another adjustment mechanism (e.g.,  1622 ). It also allows the adjustment to be achieved from a different direction (i.e., through a different surface of the housing  1606 )—through the rear side surface rather than through a top or bottom surface. 
       FIG.  21    shows an embodiment wherein the lock mechanism  2110  is rotatable relative to the housing  2106  using an adjustment portion  2122  that is accessible from the outside of the housing  2106 . Rotation of the adjustment portion  2122  about rotation axis  2125  can cause the lock mechanism  2110  to rotate from an unlocked position ( 2110 - a  shown in solid lines in  FIG.  21   ) to a locked position ( 2110 - b  shown in broken lines in  FIG.  21   ) and vice versa. The front-facing surface  2124  moves downward as it rotates until it reaches engagement with the shoulder surface  1618  and thereby prevents withdrawal of the protrusion  1600  from the housing  2106 . Further rotation of the lock mechanism  2110  drives the protrusion  1600  further inward due to protrusion movement along the slope of the front-facing surface  2124 . As a result, rotation of the lock mechanism  2110  can be used to secure the protrusion  1600  in place within the housing  2106  instead of linear translation of the lock mechanism  2110 . Rotation of the adjustment portion  2122  can be achieved by accessing the adjustment portion  2122  from a rear surface of the housing  2106 , which can improve ergonomics and allow other features (or no features at all) to be positioned around the edges of the housing  2106 . 
       FIG.  22    shows another embodiment of a terminal end of a protrusion  2200  configured to engage with and connect to an electronic device (e.g., device  1604 ). Rather than having a narrow portion and a wide portion with a shoulder surface positioned at the transition between those portions, the protrusion  2200  comprises a consistent width along its length and includes an aperture  2202  positioned between the sides of the protrusion  2200 , such as at a center thereof. The protrusion  2200  can also have an end recess  2204  aligned with the aperture  2202  (e.g., centered in the protrusion  2200 ). The aperture  2202  and recess  2204  can have sloped surfaces (e.g., their substantially vertical sides) such as outer surface  2206  positioned in the recess  2204  and, as shown in  FIG.  23 A , inner surface  2208  positioned in the aperture  2202 . The aperture  2202  can extend through the protrusion  2200  substantially perpendicular to a longitudinal axis of the protrusion that intersects the aperture  2202  and the recess  2204 . 
     The protrusion  2200  can be inserted through an opening  2210  in a housing  2212  of an electronic device and into a retainer block  2214  having an opening  2216  with guide surfaces similar to guide surfaces of central block  1634 . The end of the protrusion  2200  can therefore be guided into a tight and snug position engaging the opening  2216  similar to the position shown and described with respect to  FIG.  17 C . 
       FIG.  23 A  shows a perspective section view as taken through section lines  23 A- 23 A in  FIG.  23 B , and  FIG.  24 A  shows a perspective section view as taken through section lines  24 A- 24 A in  FIG.  24 B .  FIGS.  23 B and  24 B  show front views of the assembly of the protrusion  2200  inserted into the retainer block  2214  and housing  2212  with a latch  2218  in different locking positions. 
     In the unlocked position of  FIGS.  23 A- 23 B , the protrusion  2200  is shown inserted into the retainer block  2214  past a wedge-like (or hook-like) portion  2220  of a latch  2218  with the aperture  2202  positioned over the wedge-like portion  2220  of the latch  2218 . The protrusion  2200  is insertable to this position through the opening  2208  because the wedge-like portion  2220  is in a lowered position that leaves the opening  2208  unobstructed from within the housing  2212 . In the locked position of  FIGS.  24 A- 24 B , the protrusion  2200  is locked in the housing  2212  by the latch  2218  due to the wedge-like portion  2220  being moved upward, into the aperture  2202 , and against the inner surface  2208  thereof. The wedge-like portion  2220  can comprise a front-facing surface that engages the inner surface  2208  and that has a ramp, curvature, or slope that moves the protrusion  2200  inward through the opening  2210  as the latch  2218  moves upward, similar to how vertical motion of the front-facing surface  1624  drives the protrusion  1600  inward in a previously described embodiment. 
     The latch  2218  can also have an ejector portion  2222  which, in the locked position, is out of contact with the recess  2204 , but, in the unlocked position, has a rearward-facing surface that engages the outer surface  2206  of the recess  2204  and has a sloped surface angle that urges the protrusion in a direction directed back out of the opening  2210 . The force applied by that rearward-facing surface can increase in magnitude the further the latch  2218  moves downward. 
     A link  2224  and set of pins  2226 ,  2228  (see  FIGS.  24 A- 24 B ) can be used to move the latch  2218  between the unlocked and locked positions. The link  2224  can be rotatable about a rotation axis pin  2226 , such as via a crank or by using a tool inserted into an externally-accessible recess in the pin  2226 . See  FIG.  24 A . The rest of the link  2224  can therefore be rotated about the rotation axis pin  2226  between the position shown in  FIG.  23 B  and the position shown in  FIGS.  24 A- 24 B . A follower pin  2228  can be positioned in and received by a cam opening  2230  at a bottom end of the latch  2218 , so when the follower pin  2228  rotates about the rotation axis pin  2226 , the latch  2218  is guided and slides upward or downward due to the pin  2228  applying upward or downward pressure to the latch  2218  via the cam opening  2230 . Accordingly,  FIGS.  23 B- 24 B  show an alternative way for a latch  2218  to be driven by a rotational input being converted to a linear translation of a lock within the housing. This rotational drive input can be used with the other latches/lock mechanisms described herein. 
     With any of the embodiments described in connection with  FIGS.  16 A- 24 B , the various types of lock mechanisms, adjustment mechanisms, latches, and pins can be used interchangeably. Thus, a latch  2218  can be configured to move using a lever  2022  or screw-type adjustment mechanism  1622 , and the lock mechanism  1610  can use a rotatable link  2224 , pins  2226 ,  2228 , and cam opening  2230  to be adjusted. Thus, various combinations and modifications of the embodiments described herein can be made to adapt the interconnection systems and assemblies in ways that are customized to the needs of a designer or user. 
       FIGS.  25 A- 25 C  show another configuration of a stand-to-electronic device interconnection system  2500 . These figures show a right side view of a stand  2502  with a shaft  2504  configured to be attached to a bar  2506  within a housing  2508  of an electronic device  2510 . A fastener  2512  can join and attach the shaft  2504  to the bar  2506  at an attachment interface. When in the position shown in  FIG.  25 A , the shaft  2504  is inserted into the housing  2508  through an opening  2514  (rendering the fastener  2512  inaccessible), and a lock  2516  is positioned in a recess  2518  formed in the bar  2506 . The bar  2506  has a pivoting connection to the housing  2508  at pivot axis  2520 , but with the end of the lock  2516  in the recess  2518 , rotation of the bar  2506  out of the opening  2514  is prevented due to mechanical interference with the lock  2516 . Accordingly, the shaft  2504  is locked within the housing  2508  and is unable to be withdrawn and removed from the bar  2506  due to the presence of the fastener  2512  and the rotational immobilization of the bar  2506 .  FIG.  25 A  can therefore be referred to as being a locked configuration of the system  2500 . This configuration can beneficially hide the fastener  2512  from normal view or access from the rear of the housing  2508 , thereby giving the system  2500  heightened security and a cleaner, fastener-free appearance that reduces consumer confusion regarding which parts of the device are computing ports and which parts are structural to the electronic device. 
     When a user wishes to unlock the interconnection system  2500  and remove the shaft  2504  from the bar  2506 , the fastener  2512  must be removed. To access the fastener, a user can insert a thin tool  2522  (e.g., a credit card, spudger, flexible rod, probe, or other piece of narrow and/or flexible material) into a gap between the opening  2514  of the housing  2508  and the bar  2506  so that the tool  2522  contacts a rear-facing surface of the lock  2516 , as shown in  FIG.  25 B . In some embodiments, the user also applies an inward-directed force to the shaft  2504  to assist in pivoting rotation of the bottom end of the lock  2516  so that it is removed from the recess  2518 . The lock  2516  and bar  2506  can have parallel axes of rotation. As the lock  2516  rotates away from the recess  2518 , the tool  2522  can block the end of the lock  2516  from re-entering the recess  2518 , and the bar  2506  can rotate at pivot axis  2520  to a position exposing the end of the bar  2506  through the opening  2514  sufficient to expose the fastener  2512 , as shown in  FIG.  25 C . In some embodiments, the bar  2506  may be biased to rotate toward the exposed and unlocked position shown in  FIG.  25 C . In the exposed and unlocked position of  FIG.  25 C , the fastener  2512  can be accessed and removed, thereby allowing the shaft  2504  and bar  2506  to be separated from each other. 
     Applying an inward-directed force to the end of the bar  2506  while it is in the position shown in  FIG.  25 C  can cause it to rotate about the pivot axis  2520  to a position where the end of the lock  2516  is gravitationally drawn back into the recess  2518  to thereby automatically lock the bar  2506  in the position of  FIG.  25 A  again. In some embodiments, the lock  2516  can include a biasing device configured to apply a biasing torque to the lock  2516  that makes it rotate its end downward in a manner that prevents the lock  2516  from being dislodged from the recess  2518  due to a change in the direction of gravity working on the device. 
     The system  2500  can be used with other embodiments disclosed herein. For instance, the housing  2508  can be part of a support stand for an electronic device, and the stand  2502  can instead be an electronic device. The stand  2502  can comprise a lift arm, such as one of the arm systems described in connection with  FIGS.  13 A- 15 B . Accordingly, elements of various embodiments provided herein can be used interchangeably with other embodiments described herein. 
       FIG.  26 A  shows a partial perspective view of another interconnection system  2600  of the present disclosure. The system  2600  can connect an electronic device  2602  having a rear protrusion  2604  to a mount adapter  2606 .  FIG.  26 B  shows a top section view of the system  2600  with the mount adapter  2606  assembled to the rear protrusion  2604  and with fasteners  2607  securing the mount adapter  2606  to the rear protrusion  2604 . The section view of  FIG.  26 B  is taken through the central openings  2605  in the mount adapter  2606 . 
     The rear protrusion  2604  is rigidly anchored and connected to the electronic device  2602  (which may include attachment using any of the embodiments shown and described with respect to  FIGS.  16 A- 25 C ), thereby preventing the protrusion  2604  from substantially moving relative to the electronic device  2602 . The rear protrusion  2604  can be used to connect the electronic device  2602  to various hinge and support devices. In some embodiments, the rear protrusion  2604  can be used as a bar or device attachment structure (e.g.,  108 ,  300 ,  400 ,  500 ,  600 ,  700 ,  800 ,  1308 , or  1404 ) mountable to a tilt hinge using a pair of aligned lateral openings  2608  configured to receive a shaft or fastener (e.g.,  408 ,  808 , etc.) used to mount the protrusion  2604  to a receiver barrel (e.g.,  840 ) or receiver opening (e.g.,  320 ). The rear protrusion  2604  can comprise additional aligned lateral openings  2610  configured to connect to laterally-inserted fasteners or shafts of other tilt hinges (e.g., hinges having lateral openings or bores at a different depth relative to bores that would align with openings  2608 ). The lateral openings  2608 ,  2610  can be positioned on rearward-extending projections  2612  of the rear protrusion  2604 . The rear protrusion  2604  can also comprise a middle portion  2614  having a set of rearward-facing openings  2616 . Other embodiments disclosed herein can also implement the sets of lateral openings  2608 ,  2610  and rearward-facing openings  2616 , such as the bar and device attachment structures described above. In one example, one set of lateral openings  2608  may be used in connection to a tilt mechanism, while the other set of lateral openings  2610  may be used for connection with a lift mechanism (or vice versa). Thus, in some embodiments, the rear protrusion  2604  may be configured to be used in multiple applications, including coupling to a tilt mechanism, coupling to a lift mechanism, coupling to a rigid or fixed mount, coupling to a mount adapter, or to some other mount or connection system, including coupling with any of the systems or embodiments described herein without the need to modify the rear protrusion  2604 . 
     The mount adapter  2606  can be positioned to align the central openings  2605  with the rearward-facing openings  2616  so that the fasteners  2607  can securely join the adapter  2606  to the rear protrusion  2604 . The mount adapter  2606  can also comprise a set of rear-accessible openings  2618 . The rear-accessible openings  2618  can be used to attach the mount adapter  2606  (and the electronic device  2602 , via the protrusion  2604 ) to a support stand using fasteners attachable to the rear-accessible openings  2618 . In some embodiments, the size and spacing of the rear-accessible openings  2618  can be configured to follow standardized size and spacing metrics, such as by arranging the rear-accessible openings  2618  to be VESA-compatible or to comply with another type of monitor/computing device support standard. Alternatively, the rear-accessible openings  2618  can be arranged and configured to connect to a unique stand design. 
     In some embodiments, the mount adapter  2606  can comprise at least one front facing surface  2620  configured to engage a rear facing surface  2622  of the electronic device  2602  when the mount adapter  2606  is in use. The front facing surface  2620  can help stabilize the adapter  2606  and ensure a rigid, non-wobbling connection between the mount adapter  2606  and the electronic device  2602  (via the fasteners  2607 ). 
       FIG.  27    illustrates a partially exploded top section view of a connection assembly for a bar  2700  connectable to an electronic device  2702  and a tilt hinge  2709  that is connected to a support stand  2712 .  FIG.  28    shows an assembled top section view with the bar  2700  incorporated into the tilt hinge  2709 .  FIG.  29    shows an exploded top section view of the inner parts of the tilt hinge  2709 . The bar  2700  includes a set of axially-parallel openings  2710  configured to align with corresponding axial openings  2711  on a pin  2701  that is rotatably mounted to the lift arm  2712  within an outer barrel  2740 . The sets of openings  2710 ,  2711  can receive a set of corresponding fasteners  2715 . The fasteners  2715  can be used to fixedly mount the bar  2700  to the pin  2701  and to effectively join their structures to act as a single piece. In this manner, the pin  2701  and bar  2700  can collectively perform the functions of the bar  800 , shafts  808 - a ,  808 - b , and receiver barrel  840  of the related embodiment of  FIGS.  8 - 12   . 
     The bar  2700 , pin  2701 , and electronic device  2702  can form a display portion of the assembly that tilts at the tilt hinge  2709  relative to the lift arm  2712 . Using the fasteners  2715  can enable the tilt hinge  2709  to be assembled without externally-accessible fasteners (e.g., shafts  808 ) being exposed from the sides of the outer barrel  1240 . In other words, the fasteners  2715  can only be seen and accessed or adjusted if the user has access to the inside of the housing of the electronic device  2702 , i.e., an area that is hidden from view when the device  2702  and lift arm  2712  are in an assembled condition. 
     The outer barrel  1240  can define an interior cavity  2742  in which the inner moving parts of the tilt hinge  2709  are positioned, and the interior cavity  2742  can be closed off on its terminal ends by caps  2744  that prevent access to the tilt hinge  2709 , such as by end users or contaminants. The bar  2700  and the electronic device  2702  can be installed to the tilt hinge  2709  along an axis perpendicular to the longitudinal axis of the pin  2701  (i.e., along the dotted lines in  FIG.  27   ). The fasteners  2715  can be hidden from the end user or observer of the electronic device  2702  and stand, thereby giving the overall assembly a clean appearance and a construction that resists unwanted removal of the electronic device  2702  from the lift arm  2712  (e.g., theft) or collection of dust and debris on the fasteners. 
     The pin  2701  can be installed in the interior cavity  2742  by locating a pair of outer surfaces  2746 ,  2748  of the pin  2701  within bearings or bushings  2750 ,  2752  that are secured in place (e.g., affixed, welded in place, press-fit, attached using fasteners, etc.) to the outer barrel  2740  in the interior cavity  2742 . Thus, the bearings or bushings  2750 ,  2752  can be stationary relative to the outer barrel  2740  while the pin  2701  rotates about its longitudinal axis, and the bearings or bushings  2750 ,  2752  can prevent the longitudinal axis of the pin  2701  aligned with the centers of the bushings  2750 ,  2752  from moving relative to the outer barrel  2740 . The combination of the bar  2700  and the pin  2701  can beneficially keep the bar  2700  properly constrained and prevented from wobbling due to the tight fitment between the bearings or bushings  2750 ,  2752  and the pin  2701  and the secure fitment of the bar  2700  to the pin  2701  by the fasteners  2715 . 
     An additional fastener  2717  can be installed between a rear wall  2719  of the electronic device  2702  and an assembly opening  2721  of the bar  2700 . This fastener  2717  can be referred to as an assembly fastener or guide fastener because it can be used to assemble the bar  2700  to the rear wall  2719  before the other pin-attaching fasteners  2715  are installed. Thus, the guide fastener  2717  can be installed to help ease the assembly of the pin-attaching fasteners  2715  by holding the bar  2700  in place relative to the rear wall  2719  while the openings  2710 ,  2711  are being aligned and filled by the pin-attaching fasteners  2715  during assembly. 
     A set of friction disk components  2754  can be held in place between a bushing  2750  and an end nut  2756  mounted to threads at an end of the pin  2701 .  FIG.  29    shows these components in an exploded state, and  FIG.  28    shows them in an assembled state. The friction disk components  2754  can operate as friction disks  852 , such as to apply frictional resistance to the relative movement of the barrels  840 ,  842 . See also the descriptions of the embodiment of  FIGS.  8 - 12   , which apply to the friction disk components  2754  as well. The amount of friction applied by the friction disk components  2754  can be adjusted by adjusting the compression of those components  2754  by the end nut  2756 , thereby permitting adjustment of the amount of force required to change the tilt angle of the tilt hinge  2709 . 
     The opposite end of the pin  2701  can include an end portion  2758  on which an optional spring  2760  (e.g., a torsion spring or other elastically resilient member, such as other resilient structures described or disclosed herein) is mounted. The spring  2760  can have features and functions in common with spring  850  of the embodiment of  FIGS.  8 - 12   , including, at least in part, a first end attached to (e.g., friction-fitted, welded, or fastened to) the pin  2701  and a second end attached to (e.g., friction-fitted, welded, or fastened to) the bearing or bushing  2752 . Thus, the descriptions of the spring  850  can apply to spring  2760 . 
     In some embodiments, the spring  2760  can include one or more coils or loops having a first diameter coupled with an end of the pin  2701  and one or more coils having a second diameter (e.g., a larger diameter) coupled with the bearing or bushing  2752 . The attachment between these parts  2701 ,  2760 ,  2752  can cause the potential energy of the spring  2760  to increase or decrease as there is relative rotation between the pin  2701  and the outer barrel  2740 . Accordingly, the spring  2760  can be used to bias the rotation of the pin  2701  toward a desired “home” or “default” position where the potential energy of the spring  2760  is the lowest. In some embodiments, this position is a horizontal position, as shown in  FIG.  1 C . The number of coils or loops on the ends of the spring  2760  can correspond to the amount of friction needed to securely hold the spring  2760  to the pin  2701  and to the bearing or bushing  2752  without sliding, particularly when the spring  2760  is held in place by a press-fit or friction-fit. In some embodiments, the coils or loops of the spring  2760  have a length of at least three circumferences of their corresponding pin  2701  outer circumference or bushing  2752  outer circumference against which they engage and contact so that the spring  2760  does not slip relative to the pin  2701  or bushing  2752  as the tilt hinge  2709  rotates. In some embodiments, one circumference length or less is provided for each coil or loop, and the ends of the spring  2760  are fastened or welded to the outer surfaces of the pin  2701  and bushing  2752 , thereby minimizing the overall longitudinal length of the spring  2760 . See also the embodiment of  FIGS.  31 - 34    herein. 
     The spring  2760  can be configured to assist the user in adjusting the tilt of the electronic device  2702  when the bottom of the device is tilted forward (i.e., the movement of the electronic device  102  from the position of  FIG.  1 B  to the position shown in  FIG.  1 C ) by applying a torque to the pin  2701  and outer barrel  2740  that helps the device rotate in that direction at the tilt hinge  2709 . The spring  2760  also can resist rotation of the electronic device  2702  when the device is rotated in the opposite direction (e.g., the direction shown by the movement of the electronic device from the position of  FIG.  1 C  to the position of  FIG.  1 B ) by storing potential energy and applying a resisting torque to the tilt hinge  2709 . In this manner, the spring  2760  can improve the ergonomics of the stand (e.g.,  104 ) by making the electronic device require substantially similar (e.g., equal) torque to pivot at the tilt hinge  2709  whether it is tilted in a forward or backward direction (i.e., in a clockwise or counterclockwise direction as viewed from a lateral side thereof/parallel to the axis of rotation). The resistance and assistance of the spring  2760  can be especially beneficial in embodiments where the center of gravity of the electronic device  2702  is positioned vertically higher than the tilt hinge  2709  (e.g., at the vertical level of joint  114  in  FIG.  1 C ) so that the electronic device  2702  does not over-rotate due to the center of gravity passing over the tilt hinge  2709 . 
       FIG.  30    illustrates a side section view as taken through plane P shown in  FIG.  28    when the bar  2700  is fully inserted through the pin  2701  and the electronic device  2702  has its top end tilted rearward (similar to the position shown in  FIG.  1 B ). The bar  2700  can include a protrusion  2705  insertable into an aperture  2707  in the pin  2709 . The protrusion  2705  can have a length sufficient to extend through the axis of rotation  3001 , to extend through the aperture  2707 , and to protrude from the opposite side of the aperture  2702  relative to the flange(s) of the bar  2700  that bear(s) the set of openings  2710 . This corresponds to the position of bar  800  shown in upward rotated position  1202  in  FIG.  12   . The view of  FIG.  30    illustrates how the protrusion  2705  of the bar  2700  from the rear side of the pin  2701  can allow the bar  2700  to engage an abutment stop surface  3000  at a side surface  3002  of the bar  2700 . The electronic device  2702  can rotate about the axis of rotation  3001  to make the protrusion  2705  come into contact with a second abutment stop surface  3004  above the first stop surface  3000  and on an opposite side relative to side surface  3002 . Thus, the stop surfaces  3000 ,  3004  can define the limits of rotation of the tilt hinge  2709 . 
     Additionally, in one or both of the extreme rotated positions, a gap  3006  or small amount of clearance can be formed between a side wall of a front opening  3008  of the outer barrel  2740  and the bar  2700 . The gap  3006  can help limit wear or deformation of the surface of the bar  2700  that is visible to an end user and can help limit the amount of possible pinching of items caught between the outer barrel  2740  and the bar  2700 . The outer barrel  2740  can, in some embodiments, have a rear wall  3010  that prevents intrusion of objects into the opening  3008  from the rear side of the tilt hinge  2709 . In some embodiments, the rear wall  3010  can be omitted, and an opening can be formed in the rear side of the outer barrel  2740  between stop surfaces  3000 ,  3004 , as shown representatively in  FIG.  12   . 
     It is noted that the embodiments discussed in connection with  FIGS.  27 - 30    include features and elements that are cross-compatible and adaptable to be used in other embodiments discussed in connection with the present disclosure. For example, the tilt hinge  2709  can be used to control and support tilt in tilt joint  110 , height joint  114 , tilt hinge  1309 , tilt hinge  1411 , lift system  1500 , stand  1602 , stand  2502 , etc. Accordingly, features discussed in connection with one embodiment can be applied and used in connection with other embodiments disclosed herein. 
       FIGS.  31 - 34    illustrate aspects of a compact tilt hinge  3100  that can beneficially be used in stand and lift structures, especially where the hinge has constrained width along its axis of rotation F. For example, a compact tilt hinge  3100  can be used in an end of a lift arm (e.g., at tilt joint  110 , height joint  114 , tilt hinge  1309 , tilt hinge  1411 , lift system  1500 , stand  1602 , stand  2502 , etc.). The tilt hinge  3100  is shown at the front end of a lift arm  3101  in  FIG.  31    connecting an electronic device  3103  to a stand  3107 . The tilt hinge  3100  can be configured to fit laterally between two end blocks  3102 ,  3104  intersecting the axis of rotation F. A central pin  3105  (see the perspective section view of  FIG.  34   , taken through section lines  34 - 34  in  FIG.  32 A ) can extend between the end blocks  3102 ,  3104  and can rotate relative to the end blocks  3102 ,  3104  about the axis of rotation F. In some embodiments, the central pin  3105  can be configured to remain fixed and stationary relative to the end blocks  3102 ,  3104 . The end blocks  3102 ,  3104  can be portions of a four-bar linkage, such as, for example, a ends of tilt connector  1310  or a similar linkage component to which two parallel linkage arms (e.g.,  1314 ,  1316 ) are pivotally connected. 
     A bar  3106  can be mounted/mountable to the electronic device  3103 , similar to other bars described herein. The bar  3106  can also be mounted to a pair of movable blocks  3108 ,  3110  that are rotatable about the axis of rotation F relative to the end blocks  3102 ,  3104 . In some embodiments, the bar  3106  and at least one of the blocks  3108 ,  3110  can be formed as a single piece or as a bar assembly that operates as a single piece while assembled. Thus, the bar  3106 , when comprising one or more of the blocks  3108 ,  3110 , can include a block portion that performs the functions of the one or more blocks. The end blocks  3102 ,  3104  can include one or more stop surfaces (e.g.,  3112  in  FIGS.  32 A,  32 B,  34   ) against which at least one of the movable blocks  3108 ,  3110  can abut to provide at least one rotation limit to the hinge  3100 .  FIG.  32 A  shows the bar  3106  in a first rotated position (aligned with a longitudinal axis of the lift arm  3101 , i.e., in the position shown in  FIG.  31   ), and  FIG.  32 B  shows the bar  3106  at a second rotated position angularly displaced about the axis of rotation F relative to the first rotated position by about 15-25 degrees. In the second position, the stop surface  3112  engages the first block  3108 . 
     The tilt hinge  3100  can be used to provide counterbalance forces between the electronic device  3103  and the lift arm  3101  using an energy storage device  3114  (e.g., a spring/torsion spring, set of coils, or other elastically resilient biasing member) that is coiled around the axis of rotation F and central pin  3105 . The energy storage device  3114  can be configured similar to other energy storage devices discussed herein, wherein it can store and release energy to help smooth and ease rotation of the electronic device  3103  about the axis of rotation F while also helping to hold the electronic device  3103  in place once a user has moved the device to a chosen tilted position. To do so, the energy storage device  3114  includes a first end  3116  mounted to a first sleeve  3118  and a second end  3120  mounted to a second sleeve  3122 . The first end  3116  can include one or more coils affixed to the first sleeve  3118  (e.g., by friction-fit, welding, adhesive, etc.), and the second end  3120  can include one or more coils affixed to the second sleeve  3122  (e.g., by friction-fit, welding, adhesive, etc.). One or both of the first and second sleeves  3118 ,  3122  can have an axial opening configured to receive the central pin  3105 , as shown in  FIGS.  33 - 34   . In some embodiments, the first sleeve  3118  is mountable to the central pin  3105  and is rotated with the central pin  3105  about the longitudinal/tilt axis of rotation F, and in some embodiments, the first sleeve  3118  is mountable to the first block  3108  and does not necessarily have its rotation synchronized with central pin  3105  about axis F. The second sleeve  3122  can be an arm block which may not have a central opening, such as by being an integral part of (or permanently mounted to) an end block (e.g.,  3102 ,  3104 ) or otherwise having its motion synchronized and static relative to the end block(s) as the joint is operated. The second sleeve  3122  can be integrally formed as part of an arm block or arm block assembly that is or acts as a single piece with one or more of the end blocks  3102 ,  3104  and any intervening blocks that connect them to each other. 
     The counterbalance assembly components are shown in the exploded view of  FIG.  33   . The first end  3116  and second end  3120  can have different inner diameters to accommodate engaging different-sized outer diameters of the first sleeve  3118  and second sleeve  3122 . The second sleeve  3122  can be attached to the lift arm in a manner that remains stationary relative to the end blocks  3102 ,  3104 . Thus, rotation of the bar  3106  rotates first block  3108 , the central pin  3105 , and the first sleeve  3118  about the axis of rotation F relative to the second sleeve  3122  and the two end blocks  3102 ,  3104 . This relative rotation of the sleeves  3118 ,  3120  stores or releases energy from the energy storage device  3114  to counterbalance the movement of the electronic device  3103  relative to the lift arm  3101 .  FIGS.  32 A- 32 B  show how the parts move relative to each other and relative to the axis of rotation F. 
     The first sleeve  3118  can include set screw  3124 , other fastener, or similar removable or adjustable clamping device to adjustably affix the first sleeve  3118  to the first block  3108  and/or the central pin  3105 . The set screw  3124  can be used to tune and adjust the neutral position for the energy storage device  3114 , which can be particularly beneficial in embodiments where the center of gravity of the electronic device  3103  moves from one side (e.g., the front side) to an opposite side (e.g., the rear side) of the axis of rotation F of the tilt hinge  3100 . 
     For example, as shown in  FIG.  31   , the electronic device  3103  can have a center of gravity G 1  on a front side of the axis of rotation F when the device  3103  is in a first position. The electronic device  3103  can be tilted rearward about the axis F so that the center of gravity moves to point G 2  (directly over axis F) or to point G 3  (to the rear of axis F). While the electronic device  3103  is on the front side of the axis F and with the center of gravity at G 1 , the counterbalance energy storage device  3114  needs to provide a moment in a first direction that supports the weight of the electronic device (e.g., a clockwise moment as viewed from the angle of  FIG.  31   ). When the center of gravity moves to point G 2 , the counterbalance assembly does not need to apply any moment since the weight of the electronic device  3103  is centered over the axis F. When the center of gravity moves to point G 3 , the counterbalance assembly needs to apply a moment in a second direction (e.g., a counterclockwise moment as viewed from the angle of  FIG.  31   ) to prevent the electronic device  3103  from automatically continuing to rotate into contact with the stand  3107 . Accordingly, the energy storage device  3114  needs to provide a first counterbalance moment in a first direction when the electronic device  3103  is in a first position (corresponding to G 1 ), needs to provide no moment when the electronic device  3103  is in a second position (corresponding to G 2 ), and a second counterbalance moment in a second direction when the electronic device  3103  is in a third position (corresponding to G 3 ). 
     Due to manufacturing tolerances, assembly variations, and similar variance in the construction and assembly of the electronic device  3103 , stand  3107 , lift arm  3101 , and tilt hinge  3100 , the neutral angle for the tilt hinge  3100  (based on the neutral position of the energy storage device  3114 ) can undesirably vary. Thus, the first sleeve  3118  and set screw  3124  can enable the adjustment of the neutral position of the energy storage device  3114  during or after assembly of the tilt hinge  3100 , and the finished product can have an exactly tuned (or, if needed, an adjustably tunable) neutral angle that does not cause the electronic device  3103  to be biased to drift away from user-selected positioning. 
     Accordingly, one aspect of the disclosure relates to a method for constructing or assembling a tilt hinge, wherein the tilt hinge  3100  is assembled with the set screw  3124  loose, then the electronic device  3103  is moved to a position with its center of gravity G 2  over the axis of rotation F (or wherever the neutral angle of the energy storage device  3114  needs to be positioned), then the set screw  3124  is secured in place to fix the neutral angle of the energy storage device  3114  from then onward to the position tuned to the correct moment-transition position of the electronic device  3103  that accounts for any variance in weight, size, shape, etc. of the electronic device  3103  or the parts of the tilt hinge  3100 . 
     Furthermore, precisely configuring the position of G 2  with the neutral angle of the energy storage device  3114  can eliminate wobbles, shudders, or jumps caused by the energy storage device  3114  irregularly transitioning through its zero-moment neutral position, thereby improving the smoothness of the tilt hinge  3100  and the movement of the electronic device  3103 . Additionally, wobble and irregular movement of the electronic device at the tilt hinge can be caused by loosening of the coils of an energy storage device when it approaches or reaches its neutral position. The grip of the coils on the shaft of the hinge components (e.g., grip of the ends of energy storage device  2760  on the pin  2701  and bushing  2752 ) can at least partially loosen and unsteadily change the amount of torque applied to the hinge by the energy storage device or can provide a dead zone of lower than desired torque for a portion of the range of motion of the tilt hinge. Thus, in some embodiments, the ends of the coils of the energy storage device (e.g., ends  3116  and  3120  of device  3114 ) can be welded or otherwise permanently affixed to the structures to which the energy storage device is configured to apply torque. For that reason, the energy storage device can have a torque profile that steadily, continuously, and predictably transitions between one direction (e.g., clockwise), through zero torque (momentarily), to a second, opposite direction (e.g., counterclockwise). The smoothness and continuity of the torque profile transition can prevent jerking or dead zones in the motion of the tilt hinge  3100 . 
     To the extent applicable to the present technology, gathering and use of data available from various sources can be used to improve the delivery to users of invitational content or any other content that may be of interest to them. The present disclosure contemplates that in some instances, this gathered data may include personal information data that uniquely identifies or can be used to contact or locate a specific person. Such personal information data can include demographic data, location-based data, telephone numbers, email addresses, TWITTER® ID&#39;s, home addresses, data or records relating to a user&#39;s health or level of fitness (e.g., vital signs measurements, medication information, exercise information), date of birth, or any other identifying or personal information. 
     The present disclosure recognizes that the use of such personal information data, in the present technology, can be used to the benefit of users. For example, the personal information data can be used to deliver targeted content that is of greater interest to the user. Accordingly, use of such personal information data enables users to calculated control of the delivered content. Further, other uses for personal information data that benefit the user are also contemplated by the present disclosure. For instance, health and fitness data may be used to provide insights into a user&#39;s general wellness, or may be used as positive feedback to individuals using technology to pursue wellness goals. 
     The present disclosure contemplates that the entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with well-established privacy policies and/or privacy practices. In particular, such entities should implement and consistently use privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining personal information data private and secure. Such policies should be easily accessible by users, and should be updated as the collection and/or use of data changes. Personal information from users should be collected for legitimate and reasonable uses of the entity and not shared or sold outside of those legitimate uses. Further, such collection/sharing should occur after receiving the informed consent of the users. Additionally, such entities should consider taking any needed steps for safeguarding and securing access to such personal information data and ensuring that others with access to the personal information data adhere to their privacy policies and procedures. Further, such entities can subject themselves to evaluation by third parties to certify their adherence to widely accepted privacy policies and practices. In addition, policies and practices should be adapted for the particular types of personal information data being collected and/or accessed and adapted to applicable laws and standards, including jurisdiction-specific considerations. For instance, in the US, collection of or access to certain health data may be governed by federal and/or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA); whereas health data in other countries may be subject to other regulations and policies and should be handled accordingly. Hence different privacy practices should be maintained for different personal data types in each country. 
     Despite the foregoing, the present disclosure also contemplates embodiments in which users selectively block the use of, or access to, personal information data. That is, the present disclosure contemplates that hardware and/or software elements can be provided to prevent or block access to such personal information data. For example, in the case of advertisement delivery services, the present technology can be configured to allow users to select to “opt in” or “opt out” of participation in the collection of personal information data during registration for services or anytime thereafter. In another example, users can select not to provide mood-associated data for targeted content delivery services. In yet another example, users can select to limit the length of time mood-associated data is maintained or entirely prohibit the development of a baseline mood profile. In addition to providing “opt in” and “opt out” options, the present disclosure contemplates providing notifications relating to the access or use of personal information. For instance, a user may be notified upon downloading an app that their personal information data will be accessed and then reminded again just before personal information data is accessed by the app. 
     Moreover, it is the intent of the present disclosure that personal information data should be managed and handled in a way to minimize risks of unintentional or unauthorized access or use. Risk can be minimized by limiting the collection of data and deleting data once it is no longer needed. In addition, and when applicable, including in certain health related applications, data de-identification can be used to protect a user&#39;s privacy. De-identification may be facilitated, when appropriate, by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of data stored (e.g., collecting location data a city level rather than at an address level), controlling how data is stored (e.g., aggregating data across users), and/or other methods. 
     Therefore, although the present disclosure broadly covers use of personal information data to implement one or more various disclosed embodiments, the present disclosure also contemplates that the various embodiments can also be implemented without the need for accessing such personal information data. That is, the various embodiments of the present technology are not rendered inoperable due to the lack of all or a portion of such personal information data. For example, content can be selected and delivered to users by inferring preferences based on non-personal information data or a bare minimum amount of personal information, such as the content being requested by the device associated with a user, other non-personal information available to the content delivery services, or publicly available information. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not target to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20220307
Publication Date: 20240319
Grant Date: 20240319
Priority Date: 20210408
Inventors: DEGNER, BRETT W.
ROBINSON, KEVIN M.
PISTOR, CHRISTOPH M.
HOOSHMAND, MEHRDAD
TRIVETT, Simon J.
HAMEL, BRADLEY J.
LAURENT, KRISTOPHER P.
NARAJOWSKI, DAVID H.
Jayanathan, Stephen V
DEFOREST, LAURA M.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/1654", "inventive": true, "first": true, "tree": "[]"}, {"code": "F16M11/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/166", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1607", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K5/0221", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K5/0226", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M11/04", "inventive": true, "first": true, "tree": "[]"}, {"code": "F16M11/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1601", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1654", "inventive": true, "first": true, "tree": "[]"}, {"code": "F16M11/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M11/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C11/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C11/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C11/12", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M11/2021", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M2200/08", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M2200/041", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M2200/047", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M2200/024", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M2200/028", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1601", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M11/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M11/12", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M2200/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K5/0226", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M11/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/166", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M11/2021", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M2200/024", "inventive": false, "first": false, "tree": "[]"}, {"code": "F16M2200/041", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1607", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K5/0221", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 83509227