Patent ID: 12233007

DETAILED DESCRIPTION

Referring toFIG.1, a patient transport apparatus30is shown for supporting a patient in a health care setting. The patient transport apparatus30may be a hospital bed, stretcher, cot, wheelchair, transport chair, or similar apparatus utilized in the care of a patient. In the embodiment shown inFIG.1, the patient transport apparatus30is a cot that is utilized to transport patients, such as from an emergency site to an emergency vehicle (e.g., an ambulance).

The patient transport apparatus30shown inFIG.1includes a support structure32that provides support for the patient. The support structure32includes a base34, a support frame36, and a litter33. The base34may include a base frame35. The support frame36is spaced above the base frame35. The litter33may include a patient support deck38disposed on the support frame36. The patient support deck38may include several sections, some of which may be capable of articulating relative to the support frame36, such as a back section41, a seat section43, a leg section45, and a foot section47. The patient support deck38provides a patient support surface42upon which the patient is supported.

The base34, support frame36, patient support deck38, and patient support surface42each have a head end and a foot end corresponding to designated placement of the patient's head and feet on the patient transport apparatus30. The support frame36includes a longitudinal axis L along its length from the head end to the foot end. The support frame36also includes a vertical axis V arranged crosswise (e.g., perpendicularly) to the longitudinal axis L along which the support frame36is lifted and lowered relative to the base34. The construction of the support structure32may take on any known or conventional design, and is not limited to that specifically set forth above. In addition, a mattress (not shown) may be provided in certain embodiments, such that the patient rests directly on a patient support surface of the mattress while also being supported by the patient support surface42.

Side rails44,46are coupled to the support frame36and thereby supported by the base34. A right side rail44is positioned at a right side of the support frame36. A left side rail46is positioned at a left side of the support frame36. If the patient transport apparatus30is a hospital bed there may be more side rails. The side rails44,46may be fixed to the support frame36, or may be movable between a raised position in which they block ingress and egress into and out of the patient transport apparatus30, one or more intermediate positions, and a lowered position in which they are not an obstacle to such ingress and egress. In still other configurations, the patient transport apparatus30may not include any side rails.

Wheels58are coupled to the base34to facilitate transport over floor surfaces. The wheels58are arranged in each of four quadrants of the base34adjacent to corners of the base frame35. In the embodiment shown, the wheels58are caster wheels able to rotate and swivel relative to the support structure32during transport. Each of the wheels58forms part of a caster assembly60. Each caster assembly60is mounted to the base34. Various configurations of the caster assemblies60are contemplated. One or more of the caster wheel assemblies60may include a brake to prevent rotation of its associated caster wheel58when engaged. One or more of the caster wheel assemblies60may also include a swivel locking mechanism to prevent its associated caster wheel58from swiveling when the swivel locking mechanism is engaged. In addition, in some embodiments, the wheels58are not caster wheels and may be non-steerable, steerable, non-powered, powered, or combinations thereof. Additional wheels are also contemplated. For example, the patient transport apparatus30may include four non-powered, non-steerable wheels, along with one or more powered wheels.

In other embodiments, one or more auxiliary wheels (powered or non-powered), which may be movable between stowed positions and deployed positions, may be coupled to the support structure32. In some cases, when these auxiliary wheels are located between caster assemblies60and contact the floor surface in the deployed position, they cause two of the caster assemblies60to be lifted off the floor surface thereby shortening a wheelbase of the patient transport apparatus30. A fifth wheel may also be arranged substantially in a center of the base34.

A pair of loading wheels64(only one shown, but another is present on the opposite side) may be coupled to the support frame36to assist with loading of the patient transport apparatus30into the emergency vehicle and unloading of the patient transport apparatus30out of the emergency vehicle. In the embodiment shown, the loading wheels64are arranged nearer the head end than the foot end, but the loading wheels64may be placed in other locations to facilitate loading and/or unloading of the patient transport apparatus30into and out of the emergency vehicle, or for other purposes.

The patient transport apparatus30may further comprise a lift device70configured to raise and lower the patient support surface42between minimum and maximum heights relative to the floor surface and intermediate heights therebetween. The lift device70may be configured to operate in the same manner, or a similar manner, as the lift mechanisms shown in U.S. Pat. Nos. 8,056,950 or 9,510,981, both incorporated by reference in their entirety herein.

Turning now toFIG.2, a handle assembly80is coupled to the support frame36. The handle assembly80may be located near the foot end, head end, or locations therebetween. The handle assembly80is provided to facilitate maneuvering of the patient transport apparatus30by providing an operator a readily grasped structure. Such maneuvering includes, for example, pushing and pulling of the patient transport apparatus30on its wheels58along the floor surface and/or lifting and lowering of the patient transport apparatus30over obstacles, such as bumps or curbs, or when the patient transport apparatus30is being loaded in or unloaded from the emergency vehicle. In other embodiments, the handle assembly80may be attached to the base34, the patient support deck38, or any other suitable location on the patient transport apparatus30. Furthermore, the patient transport apparatus30may be equipped with more than one handle assembly80.

The handle assembly80includes one or more adjustable grips82configured to be grasped and manipulated by a user to facilitate maneuvering of the patient transport apparatus30, as described above. In the embodiment shown inFIGS.2-4B, each of the grips82are fixed to a respective handle link84. A crossbar85may be fixed to the grips82to space the grips82laterally and can also be used as a handle. It should be appreciated that the grips82and the crossbar85may be integral with the handle links84and/or the crossbar85, may be part of the handle links84that are intended to be grasped by users, or may be separate and distinct components that are coupled to the handle links84. Each of the handle links84comprises a shank portion that extends from the grips82to a distal end portion84a.

Turning now toFIGS.3A-4B, the handle assembly80is configured to move relative to the support frame36from a retracted position (seeFIG.3A) to one or more extended positions (seeFIGS.3B-4B). More specifically, the handle links84are able to translate relative to support frame36between the retracted position, in which the handle assembly80is positioned below the patient support surface42and within the footprint of the litter33, and a first extended position (FIG.3B), in which at least a portion of the handle assembly80is positioned outside the footprint of the litter33. The links84are slidable within rails72of the support structure32along respective translation axes T (seeFIG.3A) between the retracted position to the first extended position. The rails72each define a rail bore73aligned with the respective translation axis and extending therethrough. In the retracted position the handle links84are at least partially disposed in the rail bore73. The grips82can be grasped and used at the retracted position, the extended position, or any positions therebetween. As discussed further below, the grips82may be lockable at the retracted position, extended position, and one or more positions therebetween, and/or may be free to slide.

In some versions, the rails72are extendible and may include extension rails72athat telescope inside and relative to outer rails72b(seeFIGS.3A and3B, for example). The extensions rails72amay be configured to lock in a plurality of various extension positions relative to the outer rails72b. The rails72a,72bform part of the support frame36in their collapsed and extended configurations. In the embodiment shown, the rails72include rail end housings87that are fixed to the extension rails72ato extend/retract with the extension rails72arelative to the outer rails72b. A separate release assembly may be employed to actuate a corresponding pair of rail latch assemblies to unlock the rail latch assemblies and allow extension/retraction of the extension rails72arelative to the outer rails72b. The release assembly may include release handles or slides, but could include other forms of release devices, such as levers, buttons, and the like. The release assembly, rails72a,72b, and rail locking devices may be like those shown and described in U.S. Pat. No. 10,369,063, entitled, “Patient Transport Apparatus With Adjustable Handles,” which is incorporated by reference herein.

The grips82are located adjacent to the support frame36in the retracted position (FIG.3A) and the grips82are longitudinally spaced from the support frame36by the links84in the extended position (FIG.3B). The grips82have various uses in each of the retracted position and the extended position. In the retracted position, the grips82are conveniently located close to the support frame36so that the patient transport apparatus30can be easily moved in an elevator or other tight spaces. The grips82can be utilized in the retracted position to lift the patient transport apparatus30. In the extended position, users maintain additional clearance from patients during transport. Additionally, in the extended position, the grips82and handle links84freely articulate. This allows users of varying heights to pull the patient transport apparatus30via one or more of the grips82. Other uses of the grips82in the retracted and extended positions, and positions therebetween, are also contemplated.

With reference toFIGS.3A-4B, the handle links84may be configured to freely articulate relative to the support frame36from a first extended position as shown inFIG.3Bto a second extended position shown inFIG.4B. In some versions, the first extended position is an orientation in which the handle links84are arranged as a first angle relative to a reference axis. For example, the handle links84may be parallel to the associated rails72, and the respective translation axis T, in which they slide. The second extended position is an upright orientation relative to the support frame36in which the handle links84are arranged at a second angle relative to the reference axis. For example, the handle links84may be parallel to the vertical axis V and/or perpendicular to the respective translation axis T and support frame36. In some versions the first and second extended positions may be such that the handle links84articulate 90 degrees between the first and second extended positions, and in some cases, the handle links84may articulate less than or greater than 90 degrees between the first and second extended positions. The handle links84include extension axes E parallel with the translation axes T of the rails72in the first extended position and transverse to the translation axes T in the second extended position. In the embodiment shown inFIG.4B, the extension axes E are perpendicular to the translation axes T in the upright orientation shown. It should be appreciated that other upright orientations are possible, such as other orientations in which the extension axes E are closer to perpendicular than parallel.

The grips82are located at a first height H1relative to the support frame36in the first extended position (FIG.3B) and the grip82are located at a second height H2relative to the support frame36, greater than the first height, in the second extended position (FIG.4B). The heights H1, H2can be measured from an uppermost surface of the support frame36, from the translation axes T, from the patient support surface42(when all sections41,43,45,47are horizontal), from the floor surface, or from any other suitable location to a closest surface of the grips82, a center of mass of each of the grips82, a geometric center of each of the grips82, a topmost surface of the grips82, or to any other suitable location related to the grips82. The heights H1, H2may be measured vertically, parallel to the vertical axis V, or could be measured in other ways, such as normal to the support frame36, e.g., when the support frame36is not horizontally positioned. Regardless of the way in which the heights are measured, the grips82provide users with various advantages at each of the heights.

In the first extended position, for example, when in the retracted position and at the first height H1(FIG.3A), the grips82could be used to gain leverage and/or provide ergonomic lifting points when lifting the entire patient transport apparatus30, for instance. In the second extended position, and at the second height H2(FIG.4B), the grips82are conveniently elevated above the patient support surface42of the foot section47so that users push/pull the patient transport apparatus30along the floor surface without bending over or slouching nearer the patient to reach the grips82. The second height H2may provide higher lifting points to ease lifting over bumps, curbs, or other obstacles, such as when the patient support surface42is at a lower height. Other advantages and uses of the grips82in each of the first extended position, first height H1, second extended position, and second height H2are also contemplated.

Referring toFIGS.5A and5B, the handle assembly80includes caps88connected to the handle links84. The caps88are configured to slide along the translation axes T within the rails72from the retracted position to the extended position. In the version shown, there are two caps88, one mounted to each of the handle links84. Each cap88includes a cap body90, a limit member92, and one or more biasing devices94(e.g., one or more compression springs or other resilient elements) that urge the limit member outwardly toward an extended position. Here, the limit member is implemented as a pair of retention pins92, which are disposed in the cap body90and movable to vary distance therebetween. The biasing device94acts to push the retention pins92through diametrically opposed openings96in a sidewall98of the handle link84such that the retention pins92protrude from an outer surface of the handle link84. Other forms of caps88and limit members are also contemplated. In some versions, the caps88are integrally formed with the handle links84and/or may be formed in one-piece with the handle links84. The caps88may be formed of plastic, metal, composites thereof, or any suitable material.

Best shown inFIGS.5C and5D, a carrier100is supported by the rail end housing87and is rotatable about a pivot axis PA of the handle assembly80. The carrier100comprises a carrier body101having a curved outer surface103extending between two sides99to define a generally cylindrical shape aligned with the pivot axis PA. The carriers100are pivotally coupled to the rails72to enable articulation of the handle assembly80from the first extended position to the second extended position, and to all orientations therebetween. There is one carrier100for each of the handle links84. The carriers100are pivotally coupled to the rail end housings87.

FIGS.7and8provide additional views of one of the carriers100and its connection to one of the rail end housings87. Each carrier100has a bushing portion112protruding from each side99of the carrier body101along the pivot axis PA. In some versions, the bushing portion112includes two bushing portions112that extend on either side of the carrier body101of the carrier100. Each rail72includes a first spindle portion114and a second spindle portion116. The bushing portion112pivots about the spindle portions114,116(e.g., the bushing portion112and spindle portions114,116may have complimentary cylindrical and/or coaxial shapes to allow relative rotation). As will be discussed in further detail below, a guide118may have one of the spindle portions114,116integrally formed therewith. The guide118is attached to the rail end housing87to capture the carrier100therebetween, as best shown inFIG.8. The carriers100may be formed of plastic, metal, composites thereof, or any suitable material.

Referring again toFIGS.5C and5D, the carrier100defines a carrier aperture104, which may be an oblong-shaped passage that is sized to slidably receive the handle link84(which may also be oblong in shape) with little clearance between the outer surface of the handle link84and the carrier100. The carrier aperture104may have a geometric cross-sectional shape to generally mate with a geometric cross-sectional shape of the handle link84(e.g., both are oblong) to prevent rotation of the handle link84about the translation axis T as it slides through the carrier aperture104. In some versions, the carrier aperture104and/or handle links84may also be cylindrical in shape, or any other suitable shape for allowing telescoping of the handle link84within the carrier aperture104and along the translation axes T. The handle links84freely slide in their corresponding carrier apertures104from the retracted position to the extended position. Each carrier aperture104is sized so that the cap88is unable to pass through the carrier aperture104(i.e., thereby retaining the handle links84). To this end, each carrier100includes a stop102that is sized to prevent the cap88from sliding past the carrier100. The stop102is shown, for example, as a shoulder formed inside the carrier100. The stop102limits the telescoping travel of the handle links84by abutting the retention pins92and preventing further translation of the handle links84(seeFIG.5B).

As best shown inFIGS.5C and5D, each carrier aperture104has a first portion105and a second portion106in communication with each other. Each of the first portion105and the second portion106define a height that correspond to the cap88and the retaining pins92. More specifically, the first portion105defines a first height D1and the second portion106defines a second height D2. The first height D1corresponds to an outer distance D3(FIG.10) between the retention pins92in an extended position and is greater than the second height D2. Said differently, the outer distance D3between the retention pins92is greater than the second height D2of the second portion106of the carrier aperture104. The second height D2corresponds to an outer dimension of the cap88. More specifically, the second portion106may be sized and shaped to slidable receive the retention pins92of the cap88(seeFIG.5B). As will be discussed in further detail below, the carrier100is assembled onto the handle links84and configured with the first portion105arranged nearer to the support structure32when the handle links84are in the retracted position.

As the handle links84move between the retracted position and the first extended position the caps88remain at least partially outside of the carriers100, as shown inFIG.5A, and the carriers100are unable to freely pivot about their pivot axis PA, i.e., portions of the handle assembly80remain within the extension rails72asuch that lifting of the grips82would cause the distal end portions84aof the handle links84to bear against an inner surface of the extension rails72aand lift the patient transport apparatus30.

Referring toFIGS.6A-6D, once the cap88is fully received in both portions105,106of the carrier aperture104(seeFIG.6A), e.g., the retention pins92are fully seated against the stop102, then the handle assembly80is ready to be articulated from the first extended position to the second extended position. More specifically, the distal end portion84aof the handle links84have cleared the extension rails72ato prevent further interference with the extension rails72awhen lifting the grips82.FIGS.6B-6Dillustrate articulation of the handle assembly80to different orientations including to the second extended position (FIG.6C) and a braced position (FIG.6D). Once the handle assembly80has been placed in the second extended position, such as an upright orientation, then the carrier aperture104aligns with sockets113,115formed in the rail end housings87.

Best shown inFIGS.5A,5B, and7, each of the rail end housings87, which are operatively attached to the support structure32, comprises a guide118for supporting the carrier100for rotation about the pivot axis PA. The rail end housings87may further comprise an inner housing89and an outer housing91, which cooperate to define the guide118. The guide118may comprise a circular support surface93that is arranged about the pivot axis PA and configured to engage the curved outer surface103of the carrier100when the carrier100is received in the guide118.

As the handle links84move between the various orientations, unintended movement of the handle assembly80is prevented by a pair of shank braces. To this end, the handle assembly80may further comprise a first shank brace107and a second shank brace108adjacent to the guide118. The first shank brace107may be formed on the outer housing91aligned with the rail bore73and the second shank brace108may be formed on the inner housing89. Both the first shank brace107and the second shank brace108may further comprise an inlet face111arranged adjacent to the guide118and the carrier100to receive the handle links84. The inlet face111has a curved profile that is complementary to the curved outer surface103of the carrier100to permit rotation of the carrier100.

In order to facilitate movement of the handle assembly80between the retracted position, the first extended position, and the second extended position, each of the first shank brace107and the second shank brace108may define a corresponding socket. The first shank brace107may define a first socket113aligned with the translation axis T and the second shank brace108may define a second socket115at an angle to the translation axis T. In order to receive the handle link84when the handle assembly80is in the retracted position the first socket113has a socket dimension that is approximately equal to the first height D1if the first portion105of the carrier aperture104.

As mentioned above, the handle assembly80may be movable between the second extended position (FIG.6C) and a braced position (FIG.6D). In the braced position gravity and/or user force may then cause the handle assembly80to seat into the second socket115. More specifically, the distal end portions84aof the handle links84, which may include portions of the cap bodies90, are sized to seat into the second socket115to hold and secure the handle assembly80in the upright orientation so that the user may push/pull on the handle assembly80to maneuver the patient transport apparatus30. When seated in the second socket115, the handle links84interfere with rotation of the carriers100thereby temporarily locking the handle assembly80in the upright orientation. The distal end portions84amay have a size and/or shape (e.g., oblong, generally cylindrical, etc.) that generally matches a size and/or shape of the second socket115so that the distal end portions84a, when seated in the second socket115, are substantially retained in the second socket115and prohibited from articulating due to interference with one or more walls of the rail end housings87that define the second socket115(seeFIG.6D). The distal end portion84amay have a suitable length (e.g., 0.1 inches, 0.5 inches, 1.0 inches or more) to facilitate such interference. Movement of the handle assembly80between the first extended position and the second extended position is permitted when the distal end portion84aof the handle link84and the cap88are disposed in the carrier100. Said differently, the handle link84is disposed in neither the first socket113or the second socket115in the first extended position.

Referring toFIGS.9and10, one of the caps88is shown in greater detail. As illustrated, the cap body90has a neck120sized to slide into the handle link84and a head122sized larger than an inner passage of the handle link84to form an end surface123of the handle link84. The cap body90may also define a through passage124sized to slidably receive the retention pins92. The end surface123of the cap body90is curved so as to match the curved outer surface103of the carrier100. The curve of the end surface123allows the head122to sit flush, or nearly flush, with the cap body90when the handle is in the first and second extended positions and so that the cap88may be fully received in the guide118.

The retention pins92may have protrusions126, or other suitable geometric feature or features, to prevent the retention pins92from passing through the openings96in the sidewall98of the handle link84. The retention pins92may also have seats128to hold the biasing device94. Assembly of the cap88onto the handle link84in shown inFIG.10. Once the retention pins92are compressed and then inserted into the handle links84, the retention pins92align with the openings96in the handle links84and biasing force (e.g., spring force) from the biasing device94forces the retention pins92into their final assembled position, protruding from the outer surface of the handle links84.

FIGS.11A and11Billustrate proper assembly of the carrier100onto the handle link84and past the cap88. As shown, during assembly, the carrier100is slid onto the handle link84over the cap88until reaching the retention pins92. At that point, an operator pinches the retention pins92inwardly toward one another so that they are able to slide through the first portion105of the carrier aperture104. The operator then further slips the carrier100onto the handle link84past the retention pins92until the retention pins92reach the second portion106where they spring outwardly and prevent the handle link84from sliding back through the carrier100.FIG.11Cillustrates an attempt to improperly assemble the carrier100onto the handle link84. However, the cap88is designed to prevent such assembly. More specifically, the cap88is configured such that the cap88cannot be assembled improperly owing to the retention pins92being inaccessible to the operator in the second portion106such that the operator would be unable to pinch the retention pins92inwardly as needed to pass through the first portion105.

Referring toFIGS.12-14, the handle assembly80may further include a latch assembly configured to lock the handle assembly80relative to the rails72and the support frame36in the retracted position. The latch assembly is selectively releasable to permit movement of the grips82. The latch assembly includes a lock130having one or more first locking elements132(seeFIG.13) coupled to the rail end housing87. The lock130also has one or more second locking elements134(seeFIG.12) associated with the handle assembly80. It should be noted that, while pairs of such locking elements132,134are shown, only one first and one second locking element may be employed, or additional locking elements may be employed.

In the version shown, the first locking elements132include latches and the second locking elements134include catches adapted to receive the latches and hold the handle assembly80in a locked state. The latches shown include hooks136that are laterally movable. The hooks136form part of a latch slider138(seeFIG.14) that slides along a slide axis SA (seeFIG.13) oriented generally perpendicular to the translation axes T.

A lock housing140retains and supports the latch slider138and associated hooks136(see lock housing140with latch slider138removed inFIG.15B). In some versions, the lock housing140may include a rib structure145having a plurality of structural ribs147that are arranged to slidably support the latch slider138, as best shown inFIGS.15A and15B. The lock housing140may also include a solid slide rail along which the latch slider138slides, or other suitable structures may be used.

The lock housing140may be integrally formed with the rail end housings87or may be a separate housing. The lock housing140and the rail end housings87collectively form a foot end housing that slides via the telescoping inner and outer rails72a,72b, as previously described. The lock housing140includes a cover142(seeFIG.14) having openings144through which the hooks136protrude. The cover142captures the latch slider138within the lock housing140such that the latch slider138is retained from moving longitudinally relative to the support frame36, but is able to slide laterally relative to the support frame36along the slide axis SA.

A biasing device146, such as a compression spring or other resilient member, is located to bias the latch slider138toward a locked position by acting between the lock housing140and the latch slider138(seeFIGS.16A and16B). The biasing device146is shown applying a biasing force against the latch slider138inFIG.16Ato maintain the latch slider138in the locked position. The biasing device146is shown being further compressed inFIG.16Bwhen the latch slider138is being moved to an unlocked position during release, as described further below.

Referring toFIG.16A, the catches include openings148(e.g., slots) and crossbar portions85aof the crossbar85. The openings148are sized and shaped to receive the hooks136when the handle assembly80is moved to the retracted position. The hooks136have lead-in portions150and camming portions152that are contacted by the crossbar85to urge the hooks136laterally along the slide axis SA.

During operation, when the user pushes the handle assembly80from the extended position toward the retracted position (not shown), the lead-in portions150of the hooks136are initially longitudinally aligned with the openings148while the camming portions152are longitudinally aligned with the crossbar portions85a. With continued pushing of the handle assembly80, the crossbar portions85acontact the camming portions152. When this occurs, and with continued manual pushing of the handle assembly80in the longitudinal direction, the latch slider138and the hooks136thereof are moved laterally, against the bias of the biasing device146, until the camming portions152pass completely through the openings148. This camming action is provided by the angled shaped of the camming portions152, i.e., a longitudinally-applied force causes lateral movement. Once the camming portions152pass completely through the openings148, the hooks136are free to slide back laterally until hook portions154of the hooks136engage the wall of the crossbar85to lock the handle assembly80in a locked state (as shown inFIG.16A).

A release device includes a release160that is configured to cooperate with the latch assembly to release the first locking elements132(e.g., the hooks136) from the second locking elements134(e.g., the openings148) to allow movement of the handle assembly80from the retracted position to the extended position. The release160includes one or more manual actuators162operatively coupled to the first locking elements132. The manual actuators162are configured to be operated by the user to release the first locking elements132from the second locking elements134. Each of the manual actuators162includes an actuator body having a push-actuated plunger166(seeFIG.16A). The actuator body is retained in the lock housing140to slide longitudinally and is constrained from lateral movement. In other words, the actuator body slides along release axes RA (aligned with the plungers166) that are arranged generally transverse (e.g., perpendicular) to the slide axis SA.

Biasing devices168(e.g., compression springs or other suitable resilient members) are arranged to act between the manual actuators162and the lock housing140to bias the manual actuators162toward their unreleased positions. The lock housing140may include protruding tabs170that ride in corresponding slots172in the actuator bodies to retain the actuator bodies and constrain the plungers166to movement along the release axes RA (seeFIG.15B). The cover142of the lock housing140defines openings174also sized and shaped to retain the manual actuators162for sliding movement therein and constrain lateral movement.

During operation, as best shown inFIGS.16A and16B, when the user presses/pushes one or both of the manual actuators162to their released positions (such as with their thumbs), the plungers166are urged longitudinally along the release axes RA toward the head end of the patient transport apparatus30(see arrows inFIG.16B). Such user actuation is against the bias of their corresponding biasing devices168(see biasing devices168schematically shown in phantom inFIGS.16A and16B). When actuated, the plungers166cooperate with camming surfaces176on the latch slider138to urge the latch slider138laterally (against the bias of its biasing device146) along the slide axis SA to an unlocked position so that the hook portions154are moved out of engagement with the crossbar portions85aand instead align with the openings148(seeFIG.16B) to allow the handle assembly80to be pulled toward the extended position. Once the manual actuators162are released, they spring back to their normal, unreleased positions and the latch slider138slides back to its locked position.

Referring toFIGS.17A-20, an alternative handle assembly180is shown. In this version, handles182and handle links184move in the same manner as previously described with respect to the handle assembly80. For example, the same caps88and carriers100may be employed to cooperate with the distal end portions184aof the handle links184. However, an alternative latch assembly is employed to retain and lock the handle assembly180in the retracted position adjacent to the frame36and an alternative release device is employed to release the lock230and allow the handle assembly180to move from the retracted position to the extended position.

Referring toFIGS.21A and21B, in the version shown, the latch assembly includes a lock230having a pair of first locking elements232(one for each handle link184) and second locking elements234. The lock230may also include only a single locking element, two locking elements, or any suitable number of locking elements. The first locking elements232include latches such as locking pins236. The second locking elements234include catches such as discrete openings238that are spaced from each other along the handle links184.

Biasing devices240(e.g., compression springs or other resilient members) are arranged to bias the locking pins236toward the handle links184so that as each locking pin236(one for each handle link184) aligns with one of the discrete openings238, the locking pin236protrudes into the discrete opening238under biasing force of the biasing device240to lock the extension/retraction of the handle assembly180(seeFIG.21A). There may be one, two, three, or more discrete openings238for each of the handle links184such that the handle assembly180can be locked at the retracted position, the extended position, and/or one or more positions therebetween.

The release device includes a release260having a pair of manual actuators262(one for each lock230) that may be simultaneously pulled by the user against the bias of the biasing devices240to release the lock230, e.g., by pulling the locking pins236from their corresponding discrete openings238. In the version shown, each manual actuator262is in the form of a knob that can be grasped and pulled by a user to pull the locking pins236and allow sliding of the handle links184. A single manual actuator, or additional manual actuators may also be used in some versions. During operation, as shown inFIG.21B, the user grasps and pulls the knobs laterally (only one shown) to pull the locking pins236until the locking pins236fully clear the discrete opening238in which they were positioned (seeFIG.21B). In this version, the locking pins236are coaxially aligned with the pivot axis PA of the carriers100. The manual actuators262may also be mounted to the outer housings91that secure the carriers100in place. As shown, each of the carriers100defines a through opening242into which the locking pin236can be withdrawn to its released position (FIG.21B). In some versions, the manual actuators262may be located elsewhere and may not be aligned with the pivot axis PA, and may be utilized to facilitate locking the handle link84at various angles between the first orientation (e.g.,FIG.17B) and the second orientation (e.g.,FIG.18B).

Several examples have been discussed in the foregoing description. However, the examples discussed herein are not intended to be exhaustive or limit the invention to any particular form. The terminology that has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible in light of the above teachings and the invention may be practiced otherwise than as specifically described.