PATENT DOCUMENT

Publication Number: US-9939901-B2
Application Number: US-201514792267-A
Country: US
Kind Code: B2

Title: Haptic feedback assembly

Abstract:
A haptic feedback assembly includes interconnections for mechanically and electrically securing a haptic actuator in a track pad assembly so as to securely and efficiently provide haptic feedback to a user.

Claims:
We claim: 
     
       1. An electronic device comprising:
 a housing; 
 a track pad associated with said housing, said track pad including:
 a touch assembly that may be contacted by a user of said electronic device; 
 a force assembly associated with said touch assembly; 
 an actuator mechanically interconnected to said force assembly by a mechanical fastener; and 
 an electronic circuit board mechanically and electrically connected to the actuator by the mechanical fastener; 
 whereby an electrical signal may be conducted from the electronic circuit board to the actuator through the mechanical fastener to provide haptic feedback to said user. 
 
 
     
     
       2. The electronic device according to  claim 1  wherein said mechanical fastener is a screw. 
     
     
       3. The electronic device according to  claim 2  further including a washer positioned between said screw and said actuator. 
     
     
       4. The electronic device according to  claim 3  wherein said washer is a plastic ring press fit into said actuator. 
     
     
       5. The electronic device according to  claim 4  wherein said plastic ring is pliable. 
     
     
       6. The electronic device according to  claim 1  wherein said touch assembly is associated with said force assembly by at least one flexible pad. 
     
     
       7. The electronic device according to  claim 6  wherein said flexible pad is a foam pad. 
     
     
       8. The electronic device according to  claim 6  wherein said flexible pad is a gel pad. 
     
     
       9. A track pad comprising:
 a force assembly; 
 a touch assembly associated with said force assembly by at least one flexible pad; 
 an attraction plate mechanically attached to said force assembly; 
 an actuator electromagnetically associated with said attraction plate; and 
 an electronic board electrically and mechanically connected to said actuator by a mechanical fastener such that the electronic board sends an electrical signal to the actuator through the mechanical fastener to cause the attraction plate to move toward the actuator. 
 
     
     
       10. The track pad according to  claim 9  wherein said mechanical fastener includes solder and the electronic board is soldered to said actuator at one or more solder points. 
     
     
       11. The track pad according to  claim 9  wherein the mechanical fastener includes a screw. 
     
     
       12. The track pad according to  claim 9  wherein said flexible pad is formed from gel. 
     
     
       13. The track pad according to  claim 9  further comprising a stiffener adjacent the force assembly. 
     
     
       14. The track pad according to  claim 9  further comprising at least one force sensor mounted on the force assembly. 
     
     
       15. The track pad according to  claim 9  wherein the force assembly is H-shaped. 
     
     
       16. The track pad according to  claim 9  wherein the force assembly is rectangular with diagonal cross-beams extending between opposing corners.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a non-provisional patent application of and claims the benefit to U.S. Provisional Patent Application No. 62/057,751, filed Sep. 30, 2014 and titled “Haptic Feedback Assembly,” and U.S. Provisional Patent Application No. 62/129,943, filed Mar. 8, 2015, and titled “Haptic Feedback Assembly,” the disclosures of which are hereby incorporated herein by reference in their entirety. 
    
    
     FIELD 
     The present invention generally relates to an electromagnetic actuator for providing haptic feedback in a computing device, and more particularly to an electromagnetic actuator that is mechanically and electrically secured to a force-outputting plate. 
     BACKGROUND 
     Haptics is a tactile feedback technology that pertains to the sense of touch by applying forces, vibrations or motions to a user. This mechanical stimulation may be used to provide tactile feedback in response to an input command or system state. Haptic devices may incorporate actuators that apply forces or motion for providing touch feedback to a user. 
     One example of a haptic actuator provides mechanical motion in response to an electrical stimulus. Some haptic feedback mechanisms use mechanical technologies such as vibratory motors, like a vibrating alert in a cell phone, in which a central mass is moved to create vibrations at a resonant frequency. Other haptic feedback mechanisms use force generating devices attached to a touchpad or touchscreen to generate movement that may be sensed by a user. The quality of the haptic feedback may depend upon the mechanical and electrical interconnections between the haptic feedback mechanism and the touchscreen. 
     SUMMARY 
     Tactile feedback may be provided using an actuator connected to a touchpad. The actuator may be controlled by actuator drive signals. As a user of an electronic device interacts with the touch pad, the user may make gestures and perform other touch-related tasks. When the user desires to select an on-screen object or perform other tasks of the type traditionally associated with button or keypad actuation events, the user may press downwards against the surface of the track pad. When sufficient force is detected, appropriate action may be taken and drive signals may be applied to the actuator. 
     The actuator may impart movement to the touch pad. For example, the actuator may drive a coupling member into an edge of the planar touch pad member. Flexible pads may be formed under the force sensors to help allow the touch pad member to move laterally (in-plane with respect to the plane of the planar touch pad member) when the actuator is in operation. This may improve actuator efficiency. The actuator may move the touch pad in response to button press and release events or in response to satisfaction of other criteria in the electronic device. 
     One embodiment of the present disclosure may take the form of a method for providing haptic feedback in an electronic device. The method includes sensing a first input force by a sensor and providing, via a feedback mechanism, a first feedback corresponding to the first input force, sensing a second input force by the sensor that is at least partially in an opposite direction from the first input force, and providing, via the feedback mechanism, a second feedback corresponding to the second input force. 
     Another embodiment of the present disclosure may take the form of a haptic device for an electronic device. The haptic device includes a sensor configured to sense a user input and a feedback mechanism in communication with the sensor. The feedback mechanism is configured to provide feedback to a user. The feedback may be varied by the feedback based upon input sensed by the sensor. 
     Yet another embodiment of the present disclosure may take the form of a track pad for a computing device, the computing device including a processor. The track pad includes a touch assembly defining a user input surface and a sensor in communication with the processor. The sensor is configured to sense user force on the touch assembly. The track pad further includes an actuator connected to the touch assembly and configured to selectively impart movement to the touch assembly. The actuator moves the touch assembly in a direction and at a speed to provide feedback to a user, where the feedback is based, at least in part, on a magnitude and an acceleration of the down-stroke user input force. 
     The quality of the haptic feedback provided by the actuator is directly related to the quality of the interconnection of the actuator to the touch assembly. Secure electrical and mechanical connections of the actuator to the touch assembly are essential to provide the kind of haptic feedback necessary for a quality user experience. In some embodiments, mechanical fasteners such as screws and washers may be used to provide secure electrical and mechanical interconnections between the actuator and the touch assembly of the track pad. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an electronic device including a track pad; 
         FIG. 2  is a block diagram illustrating a computer system; 
         FIG. 3  is a schematic showing a touch assembly which includes touchpad connected to an actuator by a force assembly; 
         FIG. 4  is an exploded view of one embodiment of a force assembly, touch assembly, and actuator; 
         FIG. 5  is a side view of the embodiment illustrated in  FIG. 4  shown in an assembled implementation with an actuator interconnected with a force assembly; 
         FIG. 6  is a side view of one embodiment of an interconnect point of  FIG. 5 ; 
         FIG. 7  is a side view of an alternate embodiment of an interconnect point of  FIG. 5 ; 
         FIG. 8 , is one embodiment of the electromagnetic connection between the actuator and device board; 
         FIG. 9  is an exploded view of an alternate embodiment of a force assembly, touch assembly, and actuator assembly; 
         FIG. 10  is an assembled view of the embodiment of  FIG. 9 ; 
         FIG. 11  is a side sectional view of the assembly of  FIG. 10  taken along the lines  11 - 11 ; 
         FIG. 12  is a flow chart illustrating one method for manufacturing a track pad; and 
         FIG. 13  is a flow chart illustrating an alternate method for manufacturing a track pad. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure may be understood by reference to the following detailed description, taken in conjunction with the drawings as briefly described below. It is noted that, for purposes of illustrative clarity, certain elements in the drawings may not be drawn to scale. Like reference numerals denote like structure throughout each of the various figures. 
     When a user interacts with a portable electronic device, he or she may be asked to provide certain inputs to the portable electronic device in order for that device to determine the needs and/or wishes of the user. For example, a user may be asked to indicate which of various applications (apps) that the user wishes to access. These apps may be icons on a touchscreen and the user may touch one of these icons to select and access that app. A user may also be prompted to adjust certain functions of the portable electronic device such as sound, picture quality, and the like. This may be done by touching an indicator displayed on a touchscreen and associated with that function. In some applications on a portable electronic device, a user may be prompted to touch numbers or letters on a touchscreen to provide specific input to the portable electronic device. For example a user may spell a word or complete a form by entering a mark in a certain location. 
     In all of the above situations, a user wants to ensure that the appropriate app icon or portion of the screen that represents his or her true intention is touched. In order to satisfy this need for confirmation, the user may desire physical confirmation of this touch. Such physical confirmation could be made visually by the portable electronic device, which may confirm on a display screen that the user instructions have been received. Similarly and in some embodiments, the user may wish to receive physical confirmation in the form of haptic feedback from the portable electronic device that his or her commands or inputs have been received. This feedback may be made in the form of tactile feedback by applying forces, vibrations or motions from the portable electronic device to the person of the user. In some embodiments, this force or vibration is applied to the body part of the user that is in contact with, or otherwise accessible by, the portable electronic device. In some embodiments, this accessible portion is the finger or fingers of a user that may be in contact with the touchscreen of the device during the process of making the selection of the app or other function that he or she wishes to select. In order to provide this haptic feedback, some portable electronic devices may incorporate actuators that apply forces or motion to a track pad or touchscreen and in turn to provide touch feedback to a user. 
     Generally, embodiments described herein may take the form of a haptic assembly for providing haptic feedback to a user. A haptic actuator may provide the haptic output in response to an input signal or an output signal, or as part of an output signal. The actuator may vary its output in order to shape and control the haptic response and thus the sensation experienced by a user. In some embodiments, the actuator may be electromagnetically controlled. Embodiments described herein may be incorporated into a variety of electronic or electrical devices, such as a track pad, mouse, display, or other input (or output) device. The haptic device may be incorporated into an electronic device such as a laptop computer, smart phone, digital music player, tablet computing device, portable computing device, feedback or outputs for appliances, automobiles, touchscreens, and the like. 
     Referring to  FIG. 1 , a portable electronic device may take the form of a laptop computer system  11  and typically includes a display  21  mounted on a housing  22 . Display  21  may provide an image or video output for the electronic device  11 . Display  21  may be substantially any size and may be positioned substantially anywhere on the electronic device  11 . In some embodiments, the display  21  may be a liquid crystal display screen, plasma screen, light emitting diode screen, and so on. The display  21  may also function as an input device in addition to displaying output from the electronic device  11 . For example, display  21  may include capacitive touch sensors, infrared touch sensors, or the like that may capture a user&#39;s input to the display  21 . In these embodiments, a user may press on the display  21  in order to provide input to the electronic device  11 . In alternate embodiments display  21  may be separate from or otherwise external to the electronic device  11 , but may be in communication therewith to provide a visual output for the electronic device. 
     Referring again to  FIG. 1 , computer system  11  further may include user interfaces such as a keyboard  23  to allow a user to provide input to computer system  11 . For example, one type of input may be a user&#39;s touch or amount of force exerted on a track pad  14  by a user&#39;s finger  24 , and another type of input may be based on an accelerometer within the electronic device  11 . In addition to varying the feedback provided to a user, the haptic device and/or the processor of the electronic device may register different inputs to the haptic device differently. In other words, as the user varies his or her input to receive different types of feedback, those various inputs may also be registered by the system as different from one another. 
       FIG. 2  is a schematic illustrating a computer system including a haptic device in accordance with a sample embodiment. The computer system  11  includes a processing unit  12 , a controller  13 , and a track pad  14 . Controller  13  may execute instructions and carry out operations associated with portable electronic devices as are described herein. Using instructions from device memory, controller  13  may regulate the reception and manipulation of input and output data between components of electronic device  11 . Controller  13  may be implemented in a computer chip or chips. Various architectures can be used for controller  13  such as microprocessors, application specific integrated circuits (ASICs) and so forth. While computer system includes a processor  12  and controller  13 , in some embodiments the functions of controller  13 , as described herein, may be implemented by processing unit  12  and controller  13  may be omitted. Controller  13  together with an operating system may execute computer code and manipulate data. The operating system may be a well-known system such as iOS, Windows, Unix or a special purpose operating system or other systems as are known in the art. Controller  13  may include memory capability to store the operating system and data. Controller  13  may also include application software to implement various functions associated with portable electronic device  11 . 
     Track pad  14  may include at least one optional position sensor  16 , at least one touch sensor  17 , and at least one force sensor  18 , and one or more actuators  19  as well as a track pad plate surface  15 . Touch sensor  17  may, in some embodiments be a capacitive sensor that senses a finger or other touch through either mutual or self-capacitance. In other embodiments, a strain gauge, resistive sensor, optical sensor, and the like may be used to sense a touch. 
     In some embodiments, the position sensor(s)  16  may be an accelerometer, motion sensor, optical sensor, Hall sensor, capacitive sensor, or the like. Each of the touch sensor(s)  17 , the position sensor(s)  16 , the force sensor(s)  18  and actuator  19  are coupled to the track pad  14  and controller  13  and/or processing unit  12 . Force sensors  18  may be configured to determine an input force that may be exerted on the haptic device by a user, and the acceleration sensor  16  may be configured to determine an input speed and/or acceleration of the input force exerted on the haptic device by the user. 
     Touch sensors  17 , which, in one embodiment, may be capacitive sensors, may determine the location of one or more touches by a user on the haptic device. The touch sensor(s)  17  and the force sensor(s)  18  detect the location and force of the touch on the track pad  14  respectively and send corresponding signals to the controller  13 . The actuation member  19  may be in communication with processor  12  and/or the input sensors and may provide movement to all or a portion of the surface of track pad  14  in response to one or more signals from the processor. For example, the actuator  19  may be responsive to one or more input signals and move the feedback surface in various manners based on the one or more input signals. It should be appreciated that the force sensor(s)  18  may detect non-binary amounts of force. That is, exerted force may be detected across a continuum of values ranging from a minimum to a maximum. The force may be absolutely determined or correlated within this continuum, or the force may be assigned to one of a number of levels or bands within the continuum. In this manner the track pad  14  may be different from a switch or other conventional input device that is either closed or open, or on or off, or the like. 
     In some embodiments, the force sensor  18  may be a capacitive sensor. Such a sensor may detect force either through mutual capacitance or self-capacitance. The force sensor  18  may include multiple electrodes separated by a gap, in one embodiment. The electrodes may be formed in an array, as sheets, a single pair of electrodes, a structure divided into subsets of electrodes, and so on. Typically, the gap separates paired electrodes (e.g., one electrode of each pair is located at a corresponding side of the gap) although this is not necessary. The gap may be an air gap, a gel, a foam, and so on. 
     As a force is exerted on a surface of the haptic device (or other associated device), the gap may compress and the electrodes on either side of the gap may move closer to one another. The reduction in distance between the electrodes may increase a capacitance between the electrodes; this increase in capacitance may be correlated to the force exerted on the surface. Alternately, a single row or layer of electrodes may be positioned on one side of the gap. Capacitance between an object exerting force on the surface and one or more electrodes may increase as the gap decreases, which occurs as the force increases. Again, the change in capacitance may be correlated to an exerted force. It should be appreciated that increases in distance (e.g., increases in gap) may be correlated to decreasing force. 
     In still other embodiments, the force sensor  18  may be an ultrasonic force sensor. Ultrasonic energy may be emitted toward the surface of the track pad  14  (or other structure or device). The amount of reflected energy may vary as an object contacts the surface and/or as an object exerts force on the surface. Accordingly, the amount of energy received by an ultrasonic receiver maybe correlated to an exerted force. 
     In yet other embodiments, the force sensor may be an optical force sensor, a resistive force sensor, a strain sensor, a pyroelectric sensor, and so on. As another example, the force sensor  18  may be one or more strain gauges. As force is exerted on the structure, the force may be transmitted through one or more legs or other supports. These legs may bend or otherwise deflect in response to the exerted force. A strain gauge may be mounted to a leg, or one strain gauge to each leg, or any combination of strain gauges may be mounted to any combination of legs. Deformation of the legs may bend the strain gauges and thus induce a measurable strain. The greater the exerted force, the greater the deformation and the greater the strain. In this manner, strain may be correlated to force in a non-binary fashion. 
     As one example of the foregoing,  FIG. 4  shows an exploded view of a sample track pad with the outer surface of the pad at the bottom of the figure (e.g., the exploded view is upside down such that the interior of the track pad is at the top of  FIG. 4 ). The force assembly  26  may define multiple legs therein and a strain gauge may be mounted on each leg. As force is exerted on the track pad surface, the legs formed in the force assembly  26  may deflect or deform in the aforementioned manner. Each leg may have a strain gauge mounted thereon (not shown) to measure the corresponding strain in order to estimate an exerted force. 
     Some embodiments described herein may take the form of a haptic device for use with an associated electronic device such as computer system  11 . The haptic device may vary output provided to the user based on a number of different inputs to the haptic device. Additionally, the haptic device may vary one or more inputs provided to the computer device  11  based on the user inputs. Inputs to computer device  11  may include a processor or device command based on a system state, application activity, sensor data, and so on. Thus, the haptic device may adapt the feedback, as well as the types of input provided to computer  11  from the haptic device, based on one or more characteristics, settings, or inputs (as provided to a particular application). 
     As another example, the haptic device may provide varying feedback depending on the particular application running on the electronic device, the force input member (e.g., index finger, thumb, palm of the user), the amount of input force, the speed or acceleration of the input force, the length of time an input force is applied, location of the electronic device, and/or various other types of data inputs that may be provided to the haptic device, to the electronic device, or a combination of both. It should be noted that the data inputs to vary the output of the haptic device may be provided by a user, the haptic device, and/or the electronic device  11 . 
     One embodiment for providing haptic feedback is described below. When using track pad  14  to provide input to the computer system  11 , a user may move his or her finger  24  on track pad  14  to a desired location. The user may also touch track pad  14  at a desired location to provide input. Touch sensor(s)  17  and the force sensor(s)  18  detect the location and force of the touch on track pad  14  respectively and generate corresponding signals sent to the controller  13 . Controller  13  communicates with processing unit  12  inside computer system  11  and processing unit  12  may generally instruct controller  13  with respect to certain operations. As one non-limiting example, processing unit  12  and controller  13  in combination may use these signals to determine if the location of the touch correlates with a specific application or a user interface (UI) element. If the location is within the range for the specific application or Ul element, processing unit  12  further determines if the force signal is above a threshold. If so, processor  12  may validate the force signal as a selection of the application of UI element. In other words, if the force signal is not a false signal, then controller  13  activates actuator  19 , which moves the surface of the track pad  14  beneath the user&#39;s finger  24 . The user may sense this motion, thereby experiencing haptic feedback in response to the application or Ul element selection. Position sensor  16  detects how much track pad  14  moves relative to the actuator  19  after an actuation event, or vice versa, and may be omitted in some embodiments. 
     In another embodiment, track pad  14  may detect a user input, such as a user touch or a user force. In this example, substantially any type of detected user input may be used to provide feedback to the user. Based on the user input, track pad  14  may be activated by the processor  12  to move or vibrate to provide haptic feedback to a user. In some instances, the user input may be correlated to a specific application or UI element, in which case the location of the user input may be analyzed to determine if feedback is desired. In other instances, the mere detection of a user input may be sufficient to initiate haptic feedback. It should be noted that haptic feedback may be provided in response not only to a user input, an example of which is provided above, but also in response to system operation, software status, a lack of user input, passage of user input over Ul elements(s) (e.g., dragging a cursor over a window, icon, or the like), and/or any other operating condition of computer system  11 . 
     Referring to  FIG. 3 , a schematic of a track pad  14  with an actuator  19  is shown. As mentioned above, the quality of the haptic feedback provided to a user may depend upon the quality of the interconnections, both electrical and mechanical, that secure actuator  19  to the user-sensing surface, which may be track pad  14 . In one embodiment, one or more actuators  19  are positioned below track pad  14  and coupled thereto by a force assembly  26  to provide vibratory or other motion to track pad  14 . In another embodiment, actuators  19  may be positioned apart from track pad  14  and coupled by a force assembly  26  thereto. The coupling of track pad  14  to actuator  19  by force assembly  26  in either embodiment will be described in more detail below with respect to  FIGS. 4-13 . 
     Referring to  FIG. 4 , in one embodiment, an exploded view of an input device including a force assembly,  26 , touch assembly  25 , and actuator  19 , is shown. An attraction plate  27  and an electronic device board  28  are also shown. The interaction of actuator  19  and attraction plate  27  provide a haptic output to touch assembly  25  when the actuator  19  is energized; generally, the actuator may magnetically attract the attraction plate  27 , thereby moving the track pad  14 . When the actuator  19  is de-energized, it no longer magnetically attracts the plate  27  and the track pad  14  may be returned to its neutral/unloaded position by a restoring force exerted by a gel plate or gel structures. 
     The attraction plate  27  may be affixed to the force assembly while the actuator is affixed to the touch assembly  25  or other surface of the track pad. Flexible structures  52  may attach the track pad (and more specifically a structural layer of the track pad) to the arms formed in the force assembly  26 . The flexible pads may transmit a force exerted on the surface of the input device to the legs, shown as extensions within C-shaped cuts formed in the force assembly  18 . Force sensors  18  mounted on the legs may measure the force. Typically, the force sensors  18  may be positioned near the contact point of the flexible structures  52  with the legs, although this is not necessary. 
     The legs may be formed unitarily with the rest of the force assembly  26  by cutting a series of C-shaped trenches into the force assembly; each such trench defines a unique leg in the current embodiment. The force assembly  18  may be connected to a structural part of an associated electronic device, such as an interior plate or housing. Thus, the legs may permit some flexure or displacement of the track pad surface with respect to the force assembly by bending or otherwise deforming. As previously mentioned, this deformation may be sensed by one or more force sensor  18  and used to determine or estimate an exerted force. 
     A support structure may sit between the flexible structures  52  and the touch assembly  25 . The support structure may be formed as a square or rectangle with diagonal cross beams forming an X-shape in the middle of the support structure (e.g., extending from one diagonally opposing corner to another). This particular shape may stiffen the track pad while still permitting the transfer of force to the force sensor(s)  18  and may be lighter than a planar support structure. 
     Referring to  FIG. 5 , a side view of the embodiment illustrated in  FIG. 4  is shown in an assembled implementation with actuator  19  interconnected with force assembly  26  at interconnect points  29  which will be further described below in  FIGS. 6 and 7 . Actuator  19  is also securely connected, both electromagnetically and mechanically to board  28  at interconnect points  31  which will be further described below in  FIG. 8 . As stated above, the secure interconnection of actuator  19  to both force assembly  26  and electronic board  28  is important to ensure that quality haptic feedback is provided to a user of electronic device  11  by interacting with touch pad assembly  25  including track pad surface  14 . 
     Referring to  FIG. 6 , in one embodiment, a side view of interconnect point  29  of  FIG. 5  is shown in an expanded view. Actuator  19  is shown mechanically interconnected to force assembly  26  by a mechanical fastener such as a screw  32 . Screw  32  may be threaded into insert  33  which is attached to, and part of, force assembly  26 . Insert  33  may be glued, press fit, or otherwise attached to force assembly  26 . A spacer  34  may be included between actuator  19  and force assembly  26  to facilitate connection of actuator  19  with force assembly  26 . This secure mechanical interconnection between actuator  19  and force assembly  26  results in vibrational, lateral, or other movement by actuator  19  being efficiently transferred to force assembly  26  and thence to touch assembly  25  such that a user may benefit from haptic feedback as described herein. 
     Referring to  FIG. 7 , a side view of an alternate embodiment of interconnect point  29  of  FIG. 6  is shown in an expanded view. In this embodiment, in addition to screw  32  which is threaded into insert  33  and used to connect actuator  19  to force assembly  26 , a washer  35  may be used to further interconnect actuator  19  to force assembly  26 . Washer  35  may be a plastic ring that is press fit into a recess  36  in actuator  19 . Threaded insert  33  fits into washer  35  such that shifting movement of actuator  19  with respect to force assembly  26  is minimized or eliminated. That is, tighter tolerances than would otherwise be achievable may be maintained by use of washer  35  which in one embodiment, may be a plastic ring which may be pliable so as to reduce or eliminate gaps between insert  33  and actuator  19 . Movement of actuator  19  in the lateral direction as indicated by arrows  37  may thus be accomplished without movement of actuator  19  in recess  36  between actuator  19  and insert  33 . 
     Referring to  FIG. 8 , in one embodiment, the electromagnetic connection between actuator  19  and device board  28  is illustrated by an expanded view of interconnect points  31  from  FIG. 5 . In one embodiment, an electrically conductive mechanical fastener such as a screw  38  is used to connect actuator  19  and circuit board  28  through an electrically conductive emboss element  39 . Screw  38  provides an electrical path from actuator printed circuit board (PCB)  41  to embossed portion  39  then to screw  38  and thence to circuit board  28 . In this manner a secure electromagnetic interconnection may be made between circuit board  28  and actuator board  41 . 
     Referring to  FIG. 9 , an exploded view of an alternate embodiment of an input device including a force assembly  42 , touch assembly  43 , and actuator  44 , is shown. An attraction plate  45  and an electronic device board  46  are also shown. The interaction of force assembly  42 , actuator  44 , and attraction plate  45  provide the force to touch assembly  43  as energized through device board  46  and generally as described above with respect to other embodiments. Touch assembly  43  includes glass cover layer/top plate  47 , touch sensor layer  48  and touch grounding layer  49 , which may also be a stiffening or structural support layer in certain embodiments. An electrostatic discharge clip (or other structure)  51  may be attached between attraction plate  45  and force sensor assembly  42 . In some embodiments, the clip  51  may be made from metal, a conductive alloy, a conductive ceramic, a stiff nonconductive material having a conductive path formed therein, or the like. In other embodiments, the clip  51  may be formed from a conductive fabric and attached to the plate  45  and assembly  42  with a conductive adhesive. The use of a conductive fabric may permit the clip  51  to move, bend or flex with operation of the device or as components shift with respect to one another over time. 
     The force assembly  42  may be H-shaped, as shown in  FIG. 9 . This shape may permit or enhance localized bending of the force assembly in a region or regions occupied by the force sensor(s)  18 , thereby enhancing the ability of the sensor(s) to detect force. Insofar as the force sensor(s) are located on the underside of the force assembly in the view shown in  FIG. 9 , they are not visible in the figure. 
     Certain embodiments may incorporate a stiffener to stiffen and/or stabilize any or all of the force assembly  42 , touch assembly  43 , actuator  44 , and/or top plate  47 . The stiffener  50  may be affixed to any of a number of elements of the force assembly  42 . For example, it may be attached to the force assembly  42  near or adjacent to the attraction plate  45 . In other embodiments, the stiffener may be affixed between the force sensor assembly  42  and the top plate  47  (or a touch assembly, flex, adhesive or other layer affixed to the top plate  47 ). Such an embodiment is shown in cross-section in  FIG. 11 , for example. The stiffener  50  may be formed from any suitable material, examples of which include carbon fiber, steel, aluminum, ceramics, and so on. The stiffener  50  may be used in a variety of embodiments, including that shown in  FIG. 4 . 
     Referring to  FIG. 10 , the exploded view of  FIG. 9  is shown assembled and from a bottom view. Circuit board  46  is soldered to actuator  44  at solder pads  53  to provide the electrical power connection for actuator  44 . Force assembly  42  contacts touch assembly  43  at flexible pads  52  ( FIG. 9 ) which may be compliant foam or gel pads. Thus, force assembly  42  may move laterally at least somewhat with respect to top plate  47 , insofar as lateral motion of the force assembly  42  may apply a shear force to the gel or foam pads  52 . 
     Actuator  44  is securely mechanically attached to board  46  by a pair of screws  54 . This secure mechanical interconnection between actuator  44  and board  46  results in vibrational, lateral, or other movement by actuator  44  being efficiently transferred to force assembly  42  and then to touch assembly  43  through actuator  44  and attraction plate  45  which is securely fastened to force assembly  42  by a pair of pins  55  shown in  FIG. 10 . This secure interconnection ensures that a user may benefit from more precise haptic feedback as described herein. 
     Referring to  FIG. 11 , a side sectional view of the assembly taken along the lines  11 - 11  in  FIG. 10  is shown. Screw  54  is shown mechanically securing actuator  44  to device board assembly  46 . To provide haptic feedback, actuator  44  electromagnetically moves attraction plate  45  that is secured to force assembly  42  at pins  55 . Moving force assembly  42  in turn causes haptic feedback by moving the overall structure of the track pad. It should be appreciated that the force assembly  42  is connected to the touch assembly  43  by gel pads  52  while actuator  44  is affixed to board  46  and, ultimately, to plate  49  by mechanical fasteners. Thus, when actuator  44  magnetically attracts actuation plate  45 , the two may move closer to one another. This may induce a motion in the touch assembly  43 , since it is rigidly affixed to the actuator  44 . Essentially, the actuator  44  may move towards the attraction plate  45 , which may be rigidly and/or fixedly connected to a portion of an enclosure or otherwise prevented from moving. 
     The motion of the actuator  44 , board  46  and touch assembly  43  toward the plate  45  and force assembly  42  causes the gel pads  52  to shear. When the actuator is de-energized, the gel pads exert a restoring force that moves the actuator (and thus the majority of the track pad, including touch assembly) away from the attraction plate  45 . Accordingly, rapidly energizing and de-energizing the actuator may cause the track pad to repeatedly move back and forth quickly, thereby providing a haptic output to a person touching the track pad. 
     By securely attaching actuator  44  to board assembly  46 , the electrical interconnections, which may be solder joints  53 , do not loosen or sever from either device board assembly  46  or actuator  44 . Thus, haptic feedback can be securely and reliably provided to finger  24  of a user of track pad  14  on an electronic device such as device  11 . 
     Referring to  FIG. 12 , a method for manufacturing a track pad including a haptic feedback device includes providing a touch assembly at step  56  which may include a ground plate  49  that may also provide structural stiffness to the track pad, a sensor plate, and a glass plate for contact by a user&#39;s person. At step  57 , an actuator is connected to the force assembly. In some embodiments the actuator may be mechanically connected by screws to provide secure interconnection of the actuator with the force assembly. This secure mechanical interconnection between actuator and force assembly results in vibrational, lateral, or other movement by the actuator being efficiently transferred to the force assembly. In some embodiments a washer may be used to further interconnect the actuator to the force assembly. The washer may be a plastic ring that is press fit into a recess in the actuator. A threaded insert may be used to fit into the washer such that shifting movement of the actuator with respect to the force assembly is minimized or eliminated. That is, tighter tolerances than would otherwise be achievable may be maintained by use of the washer, which in one embodiment may be a pliable plastic ring may be that reduces or eliminates gaps between the insert and the actuator. 
     At step  58 , a device board is securely connected to the force assembly also by means of screws. In one embodiment, an electrically conductive screw is used to connect actuator and circuit board through an electrically conductive emboss element. Screw provides an electrical path from the actuator printed circuit board (PCB) to the embossed portion and then to the screw and circuit board. In this manner a secure electromagnetic interconnection may be made between the circuit board and the actuator board. The touch assembly is associated with a force assembly in step  59  which may include placement of flexible pads  52 , which may be a foam or gel pad, between the force assembly and the touch assembly. 
     Referring to  FIG. 13  an alternate method for manufacturing a track pad including a haptic feedback device includes providing a touch assembly at step  61  which includes glass cover layer, plastic (PET) touch sensor layer, and a touch grounding layer which may also provide structural stiffness in certain embodiments. At step  62 , a circuit board is soldered to the actuator to provide the electrical power connection for actuator. In some embodiments the actuator may be securely mechanically connected to the circuit board by screws. 
     In step  63 , the attraction plate is securely fastened to the force assembly by pins, thereby resulting in vibrational, lateral, or other movement by the actuator being efficiently transferred to the force assembly and then to the touch assembly through the actuator. In step  64 , the touch assembly is associated with the force assembly that may include the placement of flexible pads  52  which may be one or more foam or gel pads between force assembly and touch assembly. 
     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 intended 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: 20150706
Publication Date: 20180410
Grant Date: 20180410
Priority Date: 20140930
Inventors: PATEL DHAVAL CHANDRAKANT
HARLEY JONAH A.
AUGENBERGS PETERIS K.
DAVIS DERRYK C.
MCEUEN SCOTT J.
BROCK JOHN M.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01F7/126", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/169", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K3/325", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/016", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F2203/04103", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0414", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/10409", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/041", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/10409", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K3/325", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F7/126", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/169", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0414", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K3/325", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/169", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/10409", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/016", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0414", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04103", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/016", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 55584335