Patient transport apparatus user interface

A patient transport apparatus operable by a user for transporting a patient along stairs. A seat section is coupled to a support structure supporting a track assembly having a belt. A motor selectively generates torque to drive the belt. A user interface is arranged for engagement by the user, and has a direction input control for selecting a drive direction of the motor, and an activation input control for operating the motor to drive the belt. A controller in communication with the motor and the user interface is configured to limit operation of the motor in response to user engagement of the activation input control preceding engagement of the direction input control to prevent driving the belt, and to permit operation of the motor in response to user engagement of the activation input control following engagement of the direction input control to drive the belt in a selected drive direction.

BACKGROUND

In many instances, patients with limited mobility may have difficulty traversing stairs without assistance. In certain emergency situations, traversing stairs may be the only viable option for exiting a building. In order for a caregiver to transport a patient along stairs in a safe and controlled manner, a stair chair or evacuation chair may be utilized. Stair chairs are adapted to transport seated patients either up or down stairs, with two caregivers typically supporting, stabilizing, or otherwise carrying the stair chair with the patient supported thereon.

Certain types of conventional stair chairs utilize powered tracks to facilitate traversing stairs, whereby one of the caregivers manipulates controls for the powered tracks while also supporting the stair chair. However, these controls tend to be difficult for caregivers to engage while also supporting the stair chair, and generally require the caregiver to use one hand to support the stair chair while using the other hand to manipulate or otherwise engage the controls.

A patient transport apparatus designed to overcome one or more of the aforementioned challenges is desired.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring now to the drawings, wherein like numerals indicate like parts throughout the several views, the present disclosure is generally directed toward a patient transport apparatus100configured to allow one or more caregivers to transport a patient. To this end, the patient transport apparatus100is realized as a “stair chair” which can be operated in a chair configuration CC (seeFIGS.1and6A) to transport the patient across ground or floor surfaces FS (e.g., pavement, hallways, and the like), as well as in a stair configuration SC (seeFIGS.2and6B) to transport the patient along stairs ST. As will be appreciated from the subsequent description below, the patient transport apparatus100of the present disclosure is also configured to be operable in a stowed configuration WC (seeFIG.5) when not being utilized to transport patients (e.g., for storage in an ambulance).

As is best shown inFIG.1, the patient transport apparatus100comprises a support structure102to which a seat section104and a back section106are operatively attached. The seat section104and the back section106are each shaped and arranged to provide support to the patient during transport. The support structure102generally includes a rear support assembly108, a front support assembly110, and an intermediate support assembly112that is. The back section106is coupled to the rear support assembly108for concurrent movement. To this end, the rear support assembly108comprises rear uprights114which extend generally vertically and are secured to the back section106such as with fasteners (not shown in detail). The rear uprights114are spaced generally laterally from each other in the illustrated embodiments, and are formed from separate components which cooperate to generally define the rear support assembly108. However, those having ordinary skill in the art will appreciate that other configurations are contemplated, and the rear support assembly108could comprise or otherwise be defined by any suitable number of components. The front support assembly110comprises front struts116which, like the rear uprights114, are spaced laterally from each other and extend generally vertically. The intermediate support assembly112comprises intermediate arms118which are also spaced laterally from each other. Here too, it will be appreciated that other configurations are contemplated, and the front support assembly110and/or the intermediate support assembly112could comprise or otherwise be defined by any suitable number of components.

The intermediate support assembly112and the seat section104are each pivotably coupled to the rear support assembly108. More specifically, the seat section104is arranged so as to pivot about a rear seat axis RSA which extends through the rear uprights114(compareFIGS.5-6A; pivoting about rear seat axis RSA not shown in detail), and the intermediate arms118of the intermediate support assembly112are arranged so as to pivot about a rear arm axis RAA which is spaced from the rear seat axis RSA and also extends through the rear uprights114(compareFIGS.5-6A; pivoting about rear arm axis RAA not shown in detail). Furthermore, the intermediate support assembly112and the seat section104are also each pivotably coupled to the front support assembly110. Here, the seat section104pivots about a front seat axis FSA which extends through the front struts116(compareFIGS.5-6A; pivoting about front seat axis FSA not shown in detail), and the intermediate arms118pivot about a front arm axis FAA which is spaced from the front seat axis FSA and extends through the front struts116(compareFIGS.5-6A; pivoting about front arm axis FAA not shown in detail). The intermediate support assembly112is disposed generally vertically below the seat section104such that the rear support assembly108, the front support assembly110, the intermediate support assembly112, and the seat section104generally define a four-bar linkage which helps facilitate movement between the stowed configuration WC (seeFIG.5) and the chair configuration CC (seeFIG.6A). While the seat section104is generally configured to remain stationary relative to the support structure102when operating in the chair configuration CC or in the stair configuration CC according to the illustrated embodiments, it is contemplated that the seat section104could comprise multiple components which cooperate to facilitate “sliding” movement relative to the seat section104under certain operating conditions, such as to position the patient's center of gravity advantageously for transport. Other configurations are contemplated.

Referring now toFIGS.1-3, the front support assembly110includes a pair of caster assemblies120which each comprise a front wheel122arranged to rotate about a respective front wheel axis FWA and to pivot about a respective swivel axis SA (compareFIGS.5-6A; pivoting about swivel axis SA not shown in detail). The caster assemblies120are generally arranged on opposing lateral sides of the front support assembly110and are operatively attached to the front struts116. A lateral brace124(seeFIG.3) extends laterally between the front struts116to, among other things, afford rigidity to the support structure102. Here, a foot rest126is pivotably coupled to each of the front struts116adjacent to the caster assemblies120(pivoting not shown in detail) to provide support to the patient's feet during transport. For each of the pivotable connections disclosed herein, it will be appreciated that one or more fasteners, bushings, bearings, washers, spacers, and the like may be provided to facilitate smooth pivoting motion between various components.

The representative embodiments of the patient transport apparatus100illustrated throughout the drawings comprise different handles arranged for engagement by caregivers during patient transport. More specifically, the patient transport apparatus100comprises front handle assemblies128, pivoting handle assemblies130, and an upper handle assembly132(hereinafter referred to as “handle assembly132), each of which will be described in greater detail below. The front handle assemblies128are supported within the respective intermediate arms118for movement between a collapsed position128A (seeFIG.12A) and an extended position128B (seeFIG.12B). To this end, the front handle assemblies128may be slidably supported by bushings, bearings, and the like (not shown) coupled to the intermediate arms118, and may be lockable in and/or between the collapsed position128A and the extended position128B via respective front handle locks134(seeFIG.1). Here, a caregiver may engage the front handle locks134(not shown in detail) to facilitate moving the front handle assemblies128between the collapsed position128A and the extended position128B. The front handle assemblies128are generally arranged so as to be engaged by a caregiver during patient transport up or down stairs ST when in the extended position128B. It will be appreciated that the front handle assemblies128could be of various types, styles, and/or configurations suitable to be engaged by caregivers to support the patient transport apparatus100for movement. While the illustrated front handle assemblies128are arranged for telescoping movement, other configurations are contemplated. By way of non-limiting example, the front handle assemblies128could be pivotably coupled to the support structure102or other parts of the patient transport apparatus100. In some embodiments, the front handle assemblies128could be configured similar to as is disclosed in U.S. Pat. No. 6,648,343, the disclosure of which is hereby incorporated by reference in its entirety.

The pivoting handle assemblies130are coupled to the respective rear uprights114of the rear support assembly108, and are movable relative to the rear uprights114between a stowed position130A (seeFIG.5) and an engagement position130B (seeFIG.6A). Like the front handle assemblies128, the pivoting handle assemblies130are generally arranged for engagement by a caregiver during patient transport, and may advantageously be utilized in the engagement position130B when the patient transport apparatus100operates in the chair configuration CC to transport the patient along floor surfaces FS. In some embodiments, the pivoting handle assemblies130could be configured similar to as is disclosed in U.S. Pat. No. 6,648,343, previously referenced. Other configurations are contemplated.

The handle assembly132is also coupled to the rear support assembly108, and generally comprises an upper grip136operatively attached to extension posts138which are supported within the respective rear uprights114for movement between a collapsed position132A (seeFIGS.1and12C) and an extended position132B (seeFIGS.2and12D). To this end, the extension posts138of the handle assembly132may be slidably supported by bushings, bearings, and the like (not shown) coupled to the rear uprights114, and may be lockable in and/or between the collapsed position132A and the extended position132B via an extension lock mechanism140with an extension lock release142arranged for engagement by the caregiver. As is best shown inFIG.3, the extension lock release142may be realized as a flexible connector which extends generally laterally between the rear uprights114, and supports a cable connected to extension lock mechanisms140which releasably engage the extension posts138to maintain the handle assembly132in the extended position132B and the collapsed position132A (not shown in detail). Here, it will be appreciated that the extension lock mechanism140and/or the extension lock release142could be of a number of different styles, types, configurations, and the like sufficient to facilitate selectively locking the handle assembly132in the extended position132B. In some embodiments, the handle assembly132, the extension lock mechanism140, and/or the extension lock release142could be configured similar to as is disclosed in U.S. Pat. No. 6,648,343, previously referenced. Other configurations are contemplated.

In the representative embodiment illustrated herein, the upper grip136generally comprises a first hand grip region144arranged adjacent to one of the extension posts138, and a second hand grip region146arranged adjacent to the other of the extension posts138, each of which may be engaged by the caregiver to support the patient transport apparatus100for movement, such as during patient transport up or down stairs ST (seeFIGS.12G-12I).

As noted above, the patient transport apparatus100is configured for use int transporting the patient across floor surfaces FS, such as when operating in the stair configuration SC, and for transporting the patient along stairs ST when operating in the stair configuration SC. To these ends, the illustrated patient transport apparatus100includes a carrier assembly148arranged for movement relative to the support structure102between the chair configuration CC and the stair configuration ST. The carrier assembly148generally comprises at least one shaft150defining a wheel axis WA, one or more rear wheels152supported for rotation about the wheel axis WA, at least one track assembly154having a belt156for engaging stairs ST, and one or more hubs158supporting the shaft150and the track assembly154and the shaft150for concurrent pivoting movement about a hub axis HA. Here, movement of the carrier assembly148from the chair configuration CC (seeFIGS.1and6A) to the stair configuration SC (seeFIGS.2and6B) simultaneously deploys the track assembly154for engaging stairs ST with the belt156and moves the wheel axis WA longitudinally closer to the front support assembly110so as to position the rear wheels152further underneath the seat section104and closer to the front wheels122.

As is described in greater detail below in connection withFIGS.12A-12I, the movement of the rear wheels152relative to the front wheels122when transitioning from the chair configuration CC to the stair configuration SC that is afforded by the patient transport apparatus100of the present disclosure affords significant improvements in patient comfort and caregiver usability, in that the rear wheels152are arranged to promote stable transport across floor surfaces FS in the chair configuration CC but are arranged to promote easy transitioning from floor surfaces to stairs ST as the patient transport apparatus100is “tilted” backwards about the rear wheels152(compareFIGS.12D-12H). Put differently, positioning the rear wheels152relative to the front wheels122consistent with the present disclosure makes “tilting” the patient transport apparatus100significantly less burdensome for the caregivers and, at the same time, much more comfortable for the patient due to the arrangement of the patient's center of gravity relative to the portion of the rear wheels152contacting the floor surface FS as the patient transport apparatus100is “tilted” backwards to transition into engagement with the stairs ST.

In the representative embodiments illustrated herein, the carrier assembly148comprises hubs158that are pivotably coupled to the respective rear uprights114for concurrent movement about the hub axis HA. Here, one or more bearings, bushings, shafts, fasteners, and the like (not shown in detail) may be provided to facilitate pivoting motion of the hubs158relative to the rear uprights114. Similarly, bearings and/or bushings (not shown) may be provided to facilitate smooth rotation of the rear wheels152about the wheel axis WA. Here, the shafts150may be fixed to the hubs158such that the rear wheels152rotate about the shafts150(e.g., about bearings supported in the rear wheels152), or the shafts150could be supported for rotation relative to the hubs158. Each of the rear wheels152is also provided with a wheel lock160coupled to its respective hub158to facilitate inhibiting rotation about the wheel axis WA. The wheel locks160are generally pivotable relative to the hubs158, and may be configured in a number of different ways without departing from the scope of the present disclosure. While the representative embodiment of the patient transport apparatus100illustrated herein employs hubs158with “mirrored” profiles that are coupled to the respective rear uprights114and support discrete shafts150and wheel locks160, it will be appreciated that a single hub158and/or a single shaft150could be employed. Other configurations are contemplated.

As is best depicted inFIGS.6A-6B, the rear uprights114each generally extend between a lower upright end114A and an upper upright end114B, with the hub axis HA arranged adjacent to the lower upright end114A. The lower upright end114A is supported for movement within the hub158, which may comprise a hollow profile or recess defined by multiple hub housing components (not shown in detail inFIGS.6A-6B). The rear uprights114may each comprise a generally hollow, extruded profile which supports various components of the patient transport apparatus100. In the illustrated embodiment, the hub axis HA is arranged generally vertically between the rear arm axis RAA and the wheel axis WA.

Referring now toFIGS.7A-7B, as noted above, the track assemblies154move concurrently with the hubs158between the chair configuration CC and the stair configuration SC. Here, the track assemblies154are arranged in a retracted position154A when the carrier assembly148is disposed in the chair configuration CC, and are disposed in a deployed position154B when the carrier assembly148is disposed in the stair configuration SC. As is described in greater detail below, the illustrated patient transport apparatus100comprises a deployment linkage162and a deployment lock mechanism164with a deployment lock release166arranged for engagement by the caregiver to facilitate changing between the retracted position154A and the deployed position154B (and, thus, between the chair configuration CC and the stair configuration SC).

In the illustrated embodiment, the patient transport apparatus100comprises laterally-spaced track assemblies154each having a single belt156arranged to contact stairs ST. However, it will be appreciated that other configurations are contemplated, and a single track assembly154and/or track assemblies with multiple belts156could be employed. The track assemblies154each generally comprise a rail168extending between a first rail end168A and a second rail end168B. The second rail end168B is operatively attached to the hub158, such as with one or more fasteners (not shown in detail). An axle170defining a roller axis RA is disposed adjacent to the first rail end168A of each rail168, and a roller172is supported for rotation about the roller axis RA (compareFIGS.9A-9B). For each of the track assemblies154, the belt156is disposed in engagement with the roller172and is arranged for movement relative to the rail168in response to rotation of the roller172about the roller axis RA. Adjacent to the second rail end168B of each rail168, a drive pulley174is supported for rotation about a drive axis DA and is likewise disposed in engagement with the belt156(seeFIGS.7A-7B; rotation about drive axis DA not shown in detail). Here, the drive pulley174comprises outer teeth176which are disposed in engagement with inner teeth178formed on the belt156. The track assemblies154each also comprise a belt tensioner, generally indicated at180, configured to adjust tension in the belt156between the roller172and the drive pulley174.

In the representative embodiment illustrated herein, the patient transport apparatus100comprises a drive system, generally indicated at182, configured to facilitate driving the belts156of the track assemblies154relative to the rails168to facilitate movement of the patient transport apparatus100up and down stairs ST. To this end, and as is depicted inFIG.7A, the drive system182comprises a drive frame184and a cover186which are operatively attached to the hubs158of the carrier assembly148for concurrent movement with the track assemblies154between the retracted position154A and the deployed position154B. A motor188(depicted in phantom inFIG.7A) is coupled to the drive frame184and is concealed by the cover186. The motor188is configured to selectively generate rotational torque used to drive the belts156via the drive pulleys174, as described in greater detail below. To this end, a drive axle190is coupled to each of the drive pulleys174and extends along the drive axis DA laterally between the track assemblies154. The drive axle190is rotatably supported by the drive frame184, such as by one or more bearings, bushings, and the like (not shown in detail). A geartrain192is disposed in rotational communication between the motor188and the drive axle190. To this end, in the embodiment depicted inFIG.7A, the geartrain192comprises a first sprocket194, a second sprocket196, and an endless chain198. Here, the motor188comprises an output shaft200to which the first sprocket194is coupled, and the second sprocket196is coupled to the drive axle190. The endless chain198, in turn, is supported about the first sprocket194and the second sprocket196such that the drive axle190and the output shaft200rotate concurrently. The geartrain192may be configured so as to adjust the rotational speed and/or torque of the drive axle190relative to the output shaft200of the motor, such as by employing differently-configured first and second sprockets194,196(e.g., different diameters, different numbers of teeth, and the like).

While the representative embodiment of the drive system182illustrated herein utilizes a single motor188to drive the belts156of the track assemblies154concurrently using a chain-based geartrain192, it will be appreciated that other configurations are contemplated. By way of non-limiting example, multiple motors188could be employed, such as to facilitate driving the belts156of the track assemblies154independently. Furthermore, different types of geartrains192are contemplated by the present disclosure, including without limitation geartrains192which comprise various arrangements of gears, planetary gearsets, and the like.

The patient transport apparatus100comprises a control system202to, among other things, facilitate control of the track assemblies154. To this end, and as is depicted schematically inFIG.4, the representative embodiment of the control system202generally comprises a user interface204, a battery206, one or more sensors208, and one or more light modules210which are disposed in electrical communication with a controller212. As will be appreciated from the subsequent description below, the controller212may be of a number of different types, styles, and/or configurations, and may employ one or more microprocessors for processing instructions or an algorithm stored in memory to control operation of the motor188, the light modules210, and the like. Additionally or alternatively, the controller212may comprise one or more sub-controllers, microcontrollers, field programmable gate arrays, systems on a chip, discrete circuitry, and/or other suitable hardware, software, and/or firmware that is capable of carrying out the functions described herein. The controller212is coupled to various electrical components of the patient transport apparatus100(e.g., the motor188) in a manner that allows the controller212to control or otherwise interact with those electrical components the (e.g., via wired and/or wireless electrical communication). In some embodiments, the controller212may generate and transmit control signals to the one or more powered devices, or components thereof, to drive or otherwise facilitate operating those powered devices, or to cause the one or more powered devices to perform one or more of their respective functions.

The controller212may utilize various types of sensors208of the control system202, including without limitation force sensors (e.g., load cells), timers, switches, optical sensors, electromagnetic sensors, motion sensors, accelerometers, potentiometers, infrared sensors, ultrasonic sensors, mechanical limit switches, membrane switches, encoders, and/or cameras. One or more sensors208may be used to detect mechanical, electrical, and/or electromagnetic coupling between components of the patient transport apparatus100. Other types of sensors208are also contemplated. Some of the sensors208may monitor thresholds movement relative to discrete reference points. The sensors208can be located anywhere on the patient transport apparatus100, or remote from the patient transport apparatus100. Other configurations are contemplated.

It will be appreciated that the patient transport apparatus100may employ light modules210to, among other things, illuminate the user interface204, direct light toward the floor surface FS, and the like. It will be appreciated that the light modules210can be of a number of different types, styles, configurations, and the like (e.g., light emitting diodes LEDs) without departing from the scope of the present disclosure. Similarly, it will be appreciated that the user interface204may employ user input controls of a number of different types, styles, configurations, and the like (e.g., capacitive touch sensors, switches, buttons, and the like) without departing from the scope of the present disclosure.

The battery206provides power to the controller212, the motor188, the light modules210, and other components of the patient transport apparatus100during use, and is removably attachable to the cover186of the drive system182in the illustrated embodiment (seeFIG.7A; attachment not shown in detail). The user interface204is generally configured to facilitate controlling the drive direction and drive speed of the motor188to move the belts156of the track assembly154and, thus, allow the patient transport apparatus100to ascend or descend stairs ST. Here, the user interface204may comprise one or more activation input controls214to facilitate driving the motor188in response to engagement by the caregiver, one or more direction input controls216to facilitate changing the drive direction of the motor188in response to engagement by the caregiver, and/or one or more speed input controls218to facilitate operating the motor188at different predetermined speeds selectable by the caregiver. The user interface204may also comprise various types of indicators220to display information to the caregiver. It will be appreciated that the various components of the control system202introduced above could be configured and/or arranged in a number of different ways, and could communicate with each other via one or more types of electrical communication facilitated by wired and/or wireless connections. Other configurations are contemplated.

The activation input controls214may be arranged in various locations about the patient transport apparatus. In the illustrated embodiments, a first activation input control222is disposed adjacent to the first hand grip region144of the handle assembly132, and a second activation input control224is disposed adjacent to the second hand grip region146. In the illustrated embodiment, the user interface204is configured such that the caregiver can engage either of the activation input controls222,224with a single hand grasping the upper grip136of the handle assembly132during use.

In the illustrated embodiments, the patient transport apparatus100is configured to limit movement of the belts156relative to the rails168during transport along stairs ST in an absence of engagement with the activation input controls214by the caregiver. Put differently, one or more of the controller212, the motor188, the geartrain192, and/or the track assemblies154may be configured to “brake” or otherwise prevent movement of the belts156unless the activation input controls214are engaged. To this end, the motor188may be controlled via the controller212to prevent rotation (e.g., driving with a 0% pulse-width modulation PWM signal) in some embodiments. However, other configurations are contemplated, and the patient transport apparatus100could be configured to prevent movement of the belts156in other ways. By way of non-limiting example, a mechanical brake system (not shown) could be employed in some embodiments.

Referring now toFIGS.7A-9B, the patient transport apparatus100employs the deployment lock mechanism164to releasably secure the track assembly154in the retracted position154A and in the deployed position154B. As is described in greater detail below, the deployment lock release166is arranged for engagement by the caregiver to move between the retracted position154A and the deployed position154B. The deployment lock mechanism164is coupled to the track assemblies154for concurrent movement, and the deployment linkage162is coupled between the deployment lock mechanism164and the support structure102. The illustrated deployment linkage162generally comprises connecting links226which are pivotably coupled to the support structure102, and brace links228which are coupled to the deployment lock mechanism164and are respectively pivotably coupled to the connecting links226.

As is best shown inFIG.9A, the connecting links226each comprise or otherwise define a forward pivot region230, a connecting pivot region232, a trunnion region234, and an interface region236. The forward pivot regions230extend from the interface regions236to forward pivot mounts238which are pivotably coupled to the rear uprights114about the rear seat axis RSA, such as by one or more fasteners, bushings, bearings, and the like (not shown in detail). Here, because the rear uprights114are spaced laterally away from each other at a distance large enough to allow the track assemblies154to “nest” therebetween in the retracted position154A (seeFIG.7A), the forward pivot regions230of the connecting links226extend at an angle away from the rear uprights114at least partially laterally towards the track assemblies154. The trunnion regions234extend generally vertically downwardly from the interface regions236to trunnion mount ends240, and comprise trunnions242which extend generally laterally and are arranged to abut trunnion catches244of the deployment lock mechanism164to retain the track assemblies154in the retracted position154A (seeFIG.7A) as described in greater detail below. The connecting pivot regions232extend longitudinally away from the interface regions236to rearward pivot mounts246which pivotably couple to the brace links228about a link axis LA. The connecting pivot regions232also comprise link stops248that are shaped and arranged to abut the brace links228in the deployed position154B (seeFIG.7B), as described in greater detail below. The connecting links226are each formed as separate components with mirrored profiles in the illustrated embodiments, but could be realized in other ways, with any suitable number of components.

The brace links228each generally extend between an abutment link end250and a rearward link mount252, with a forward link mount254arranged therebetween. The forward link mounts254are pivotably coupled to the rearward pivot mounts246of the connecting links226about the link axis LA, such as by one or more fasteners, bushings, bearings, and the like (not shown in detail). The rearward link mounts252are each operatively attached to the deployment lock mechanism164about a barrel axis BA, as described in greater detail below. The brace links228each define a link abutment surface256disposed adjacent to the abutment link end250which are arranged to abut the link stops248of the connecting links226in the deployed position154B (seeFIGS.7B and9B). The brace links228also define a relief region258formed between the forward link mount254and the rearward link mount252. The relief regions258are shaped to at least partially accommodate the link stops248of the connecting links226when the track assemblies154are in the retracted position154A (not shown in detail).

Referring now toFIG.8, the deployment lock release166of the deployment lock mechanism164is supported for movement within a lock housing260which, in turn, is coupled to and extends laterally between the rails168of the track assemblies154(e.g., secured via fasteners; not shown). The deployment lock release166is formed as a unitary component in the illustrated embodiment, and generally comprises a deployment body262, a deployment button264, one or more push tabs266, and the trunnion catches244. The deployment button264is arranged for engagement by the caregiver, extends vertically downwardly from the deployment body262, and is disposed laterally between the trunnion catches244. The one or more push tabs266extend vertically upwardly from the deployment body262to respective push tab ends268, and are employed to facilitate releasing the track assemblies154from the deployed position154B as described in greater detail below. The trunnion catches244each define a retention face270arranged to abut the trunnions242of the connecting links226when the track assemblies154are in the retracted position154A (seeFIG.7A; not shown in detail). The trunnion catches244also each define a trunnion cam face272arranged to engage against the trunnions242of the connecting links226as the track assemblies154are brought toward the deployed position154B from the retracted position154A. While not shown in detail throughout the drawings, engagement of the trunnions242against the trunnion cam faces272urges the deployment body262vertically upwardly within the lock housing260until the trunnions242come out of engagement with the trunnion cam faces272. Here, one or more biasing elements (not shown) may bias the deployment lock release166vertically downwardly within the lock housing260such that disengagement of the trunnions242with trunnion cam faces272occurs as the track assemblies154reach the deployed position154B and the trunnions242come into engagement with the retention faces270(seeFIG.7A; not shown in detail).

With continued reference toFIG.8, the deployment lock mechanism164also comprises a barrel274supported for rotation about the barrel axis BA (compareFIGS.9A-9B) within a cylinder housing276which, in turn, is coupled to and extends laterally between the rails168of the track assemblies154(e.g., secured via fasteners; not shown). The barrel274defines barrel notches278which receive the rearward link mounts252of the brace links228therein. Here, the cylinder housing276comprises transverse apertures280aligned laterally with the barrel notches278and shaped to receive the brace links228therethrough to permit the brace links228to move generally concurrently with the barrel274relative to the cylinder housing276. Here, the barrel notches278and the rearward link mounts252are provided with complimentary profiles that allow the brace links228to pivot about the barrel axis BA as the barrel274rotates within the cylinder housing276. The barrel notches278may be sized slightly larger than the rearward link mounts252to prevent binding. However, it will be appreciated that other configurations are contemplated. The barrel274also comprises push notches282arranged laterally between the barrel notches278. The push notches282are shaped to receive the push tab ends268of the push tabs266to facilitate releasing the track assemblies154from the deployed position154B in response to the caregiver engaging the deployment button264. As depicted inFIG.9A, retention of the track assemblies154in the deployed position154B is achieved based on the geometry of the deployment linkage162acting as an “over center” lock.

More specifically, when the track assemblies154move to the deployed position154B, the link axis LA is arranged below a linkage plane LP defined extending through the rear seat axis RSA and the barrel axis BA, and will remain in the deployed position154B until the link axis LA is moved above the linkage plane LP (seeFIG.9B). To this end, the caregiver can engage the deployment button264to bring the push tab ends268of the push tabs266into engagement with the push notches282formed in the barrel274which, in turn, rotates the barrel274about the barrel axis BA as the push tab ends268contact the barrel274within the push notches282, and pivots the brace links228about the barrel axis BA to cause the link axis LA to move above the linkage plane LP as shown inFIG.9B. It will be appreciated that the deployment lock mechanism164could be configured in other ways sufficient to releasably lock the track assemblies154in the retracted position154A and the deployed position154B, and it is contemplated that one lock mechanism could lock the track assemblies154in the retracted position154A while a different lock mechanism could lock the track assemblies154in the deployed position154B. Other configurations are contemplated.

Referring now toFIGS.10-11D, the patient transport apparatus100employs a folding lock mechanism284to facilitate changing between the stowed configuration WC (seeFIG.5) and the chair configuration CC (seeFIG.6A). To this end, the folding lock mechanism284generally comprises a folding lock release286(seeFIG.10) operatively attached to the back section106and arranged for engagement by the caregiver to releasably secure the folding lock mechanism284between a stow lock configuration284A to maintain the stowed configuration WC, and a use lock configuration284B to prevent movement to the stowed configuration WC from the chair configuration CC or from the stair configuration SC. To this end, the folding lock mechanism284generally comprises a folding link288with folding pivot mounts290and sliding pivot mounts292. The folding pivot mounts290are pivotably coupled to the seat section104about an upper folding axis UFA that is arranged between the rear seat axis RSA and the front seat axis FSA (seeFIGS.2and6A-6B; pivoting not shown in detail). The sliding pivot mounts292each comprise a keeper shaft294which extends along a lower folding axis LFA which is arranged substantially parallel to the upper folding axis UFA. The keeper shafts294are disposed within and slide along slots296formed in each of the rear uprights114. For the illustrative purposes, the keeper shafts294are shown inFIGS.11A-11Das sized significantly smaller than the width of the slots296. The slots296extend generally vertically along the rear uprights114between an upper slot end298and a transition slot region300, and extend at an angle from the transition slot region300to a lower slot end302. The slots296are disposed vertically between the rear seat axis RSA and the rear arm axis RAA in the illustrated embodiment. In some embodiments, the folding link288, the slots296, and or other portions of the folding lock mechanism284may be similar to as is disclosed in U.S. Pat. No. 6,648,343, previously referenced. Other configurations are contemplated.

In the representative embodiment illustrated herein, the folding lock mechanism284is configured to selectively retain the keeper shafts294adjacent to the upper slot ends298of the slots296in the stow lock configuration284A (seeFIG.11A), and to selectively retain the keeper shafts294adjacent to the lower slot ends302of the slots296in the use lock configuration284B (seeFIG.11C). To this end, keeper elements304are coupled to the keeper shafts294and move within upright channels306formed in the rear uprights114. Here too, a carriage308is slidably supported within the upright channels306for movement relative to the slots296in response to engagement of the folding lock release286via the caregiver. A folding linkage assembly310generally extends in force-translating relationship between the folding lock release286and the carriage308. While not shown in detail, the folding lock release286is supported by the back section106and moves in response to engagement by the caregiver, and the folding linkage assembly310comprises one or more components which may extend through the back section106and into the rear uprights114in order to facilitate movement of the carriage308within the upright channels306in response to user engagement of the folding lock release286. As will be appreciated from the subsequent description below,FIGS.11A and11Crepresent an absence of user engagement with the folding lock release286, whereasFIGS.11B and11Drepresent user engagement with the folding lock release286.

The carriage308generally defines an upper pocket312shaped to receive and accommodate the keeper element304when the folding lock mechanism284is in the stow lock configuration284A with the patient transport apparatus100arranged in the stowed configuration WC, and a lower pocket314shaped to receive and accommodate the keeper element304when the folding lock mechanism284is in the use lock configuration284B with the patient transport apparatus100arranged in the chair configuration CC or in the stair configuration SC. In the illustrated embodiment, the upper pocket312has a generally U-shaped profile and the lower pocket314has a generally V-shape profile which defines a upper ramp316and a lower ramp318. The keeper element304has a par of substantially parallel sides which are shaped to be received within the upper pocket312(not shown in detail).

As shown inFIG.11A, engagement between the keeper element304and the upper pocket312of the carriage308prevents movement of the keeper shaft294along the slot296. When the caregiver engages the folding lock release286to move the folding lock mechanism284out of the stow lock configuration284A, the corresponding movement of the folding linkage assembly310causes the carriage308to travel vertically upwardly within the upright channel306until the keeper element304comes out of engagement with the upper pocket312, as shown inFIG.11B. Here, the keeper shaft294can subsequently traverse the slot296toward the lower slot end302in order to move to the use lock configuration284B depicted inFIG.11C(movement not shown; compareFIG.11BtoFIG.11C). While not shown, it will be appreciated that the carriage308, the folding linkage assembly310, and or the folding lock release286may comprise one or more biasing elements arranged to urge the carriage308vertically down the upright channel306.

When in the use lock configuration284B depicted inFIG.11C, the keeper shaft294is disposed adjacent to the lower slot end302of the slot296such that the keeper element304is generally disposed adjacent to or otherwise in the lower pocket314, such as in contact with the upper ramp316and the lower ramp318. Here, the keeper element304is retained via a folding lock biasing element320(depicted schematically) that is coupled to the rear upright114(e.g., disposed within the upright channel306). To this end, the keeper element304has a notch side that abuts the folding lock biasing element320and is arranged transverse (e.g., non-parallel) to the two parallel sides (not shown in detail). The engagement between the keeper element304and folding lock biasing element320urges the keeper shaft294toward the lower slot end302of the slot296to maintain operation in the use lock configuration284B depicted inFIG.11C. When the caregiver engages the folding lock release286to move the folding lock mechanism284out of the use lock configuration284B, the corresponding movement of the folding linkage assembly310causes the carriage308to travel vertically upwardly within the upright channel306. Here, as the lower ramp318of the carriage308defined by the lower pocket314moves together with the keeper element304disposed in engagement therewith, the folding lock biasing element320compresses as the keeper shaft294travels out of the transition slot region300, as shown inFIG.11D. Here, the keeper shaft294can subsequently traverse the slot296toward the upper slot end298in order to move to the stow lock configuration284A depicted inFIG.11A(movement not shown; compareFIG.11DtoFIG.11A). It will be appreciated that the folding lock mechanism284could be configured in other ways sufficient to releasably lock the patient transport apparatus in the stowed configuration WC, the stair configuration SC, and the chair configuration CC, and it is contemplated that one lock mechanism could lock the patient transport apparatus100in the stowed configuration WC while a different lock mechanism could lock the patient transport apparatus100in the stair configuration SC and/or the chair configuration CC. Other configurations are contemplated.

FIGS.12A-12Isuccessively depict exemplary steps of transporting a patient supported on the patient transport apparatus100down stairs ST. InFIG.12A, a first caregiver is shown engaging the pivoting handle assemblies130in the engagement position130B to illustrate approaching stairs ST while the patient transport apparatus100is moved along floor surfaces FS in the chair configuration CC.FIG.12Bdepicts a second caregiver engaging the front handle assemblies128after having moved them to the extended position128B. InFIG.12C, the patient transport apparatus100has been moved closer to the stairs ST with the first caregiver still engaging the pivoting handle assemblies130and with the second caregiver still engaging the front handle assemblies128. InFIG.12D, the first caregiver has moved the handle assembly132to the extended position132B as the second caregiver continues to engage the front handle assemblies128.

InFIG.12E, the first caregiver has engaged the deployment lock release166to move the patient transport apparatus100out of the chair configuration CC and into the stair configuration SC. Here, the track assemblies154are shown arranged between the retracted position154A and the deployed position154B, and the rear wheels152move closer to the front wheels122, as the first caregiver pulls the track assemblies154away from the back section106. InFIG.12F, the patient transport apparatus100is shown in the stair configuration SC with the track assemblies154arranged in the deployed position154B. Here, the rear wheels152are positioned significantly closer to the front wheels122compared to operation in the chair configuration CC, and are also arranged further under the seat section104. It will be appreciated that transitioning the patient transport apparatus100from the chair configuration CC to the stair configuration SC has resulted in minimal patient movement relative to the support structure102as the carrier assembly148pivots about the hub axis HA and moves the rear wheels152closer to the front wheels122in response to movement of the track assemblies154to the deployed position154B.

Furthermore, while the arrangement of patient's center of gravity has not changed significantly relative to the support structure102, the longitudinal distance which extends between the patient's center of gravity and the location at which the rear wheels152contact the floor surface FS has shortened considerably. Because of this, the process of “tilting” the patient transport apparatus100(e.g., about the rear wheels152) to transition toward contact between the track assemblies154and the stairs ST, as depicted inFIG.12G, is significantly more comfortable for the patient than would otherwise be the case if the patient transport apparatus100were “tilted” about the rear wheels152from the chair configuration CC (e.g., with the rear wheels152positioned further away from the front wheels122). Put differently, the arrangement depicted inFIG.12Gis such that the patient is much less likely to feel uncomfortable, unstable, or as if they are “falling backwards” during the “tilting” process. Here too, the caregivers are afforded with similar advantages in handling the patient transport apparatus100, as the arrangement of the rear wheel152described above also makes the “tilting” process easier to control and execute.

InFIG.12H, the caregivers are shown continuing to support the patient transport apparatus100in the stair configuration SC as the belts156of the track assemblies154are brought into contact with the edge of the top stair ST. InFIG.12I, the caregivers are shown continuing to support the patient transport apparatus100in the stair configuration SC as the belts156of the track assemblies154contact multiple stairs ST during descent.

As noted above, the representative embodiment of the patient transport apparatus100illustrated herein employs the control system202to, among other things, facilitate operation of the drive system182via the controller212in response to caregiver engagement with the user interface204.

Referring now toFIGS.4and13, a representative embodiment of the user interface204of the patient transport apparatus100is depicted schematically. As noted above, in some embodiments, the user interface204may include one or more activation input controls214(e.g., the first and second activation input controls222,224) that are disposed in communication with the controller212. Here too, in some embodiments, the user interface204may include one or more direction input controls216, such as a first direction input control322and a second direction input control324, to facilitate changing the drive direction of the motor188. Furthermore, in some embodiments, the user interface204may include one or more speed input controls218, such as a first speed input control326and a second speed input control328, to facilitate operating the motor188at different predetermined speeds. Moreover, in some embodiments, the user interface204may include one or more indicators220to display information to the caregiver, such as a battery indicator330to display information about the charge of the battery206, and such as a speed indicator332to display information about the selected drive speed of the motor188. In some embodiments, the user interface204may include an area light input control334arranged for engagement by the caregiver to operate a light module210realized as an area light module336arranged to illuminate the area surrounding the patient transport apparatus100(seeFIGS.1-2). Each of the components of the user interface204introduced above will be described in greater detail below.

In some embodiments, the user interface204may comprise one or more light modules210realized as backlight modules338arranged to illuminate various input controls214,216,218,222,224,322,324,326,328and/or indicators220,330,332under certain operating conditions. In some embodiments, the user interface204may comprise one or more light modules210configured to, among other things, provide status information to the caregiver. In some embodiments, one or more direction light modules340could be provided adjacent to the direction input control(s)216,322,324to indicate a selected drive direction to the caregiver, alert the caregiver of a need to interact with the user interface204, and the like. In some embodiments, one or more activation light modules342could be provided adjacent to the activation input controls214,222,224to indicate a current operating state of the patient transport apparatus100(e.g., the operating state of the motor188) to the caregiver, alert the caregiver of a need to interact with the user interface204, and the like. In some embodiments, one or more area light input modules344could be provided adjacent to the area light input control334to indicate a status of the area light module336to the caregiver, alert the caregiver of a need to interact with the user interface204, and the like. In some embodiments, one or more battery light modules346may be provided as a part of (or otherwise adjacent to) the battery indicator330to indicate a status of the charge state of the battery206to the caregiver, alert the caregiver of a need to interact with the user interface204, and the like. In some embodiments, one or more speed light modules348may be provided as a part of (or otherwise adjacent to) the speed indicator332and/or the speed input control(s)218,326,328to indicate a selected one of a plurality of drive speed DS1, DS2, DS3to the caregiver, alert the caregiver of a need to interact with the user interface204, and the like. Each of the light modules210introduced above will be described in greater detail below.

In the representative embodiment illustrated herein, the controller212may be operable in a sleep mode MS in which power consumption is limited, and an active mode MA in which the controller212facilitates operation of the motor188of the patient transport apparatus100. As noted above, the one or more light modules210may include one or more backlight modules338disposed in communication with the controller212. The controller212may be configured to operate the backlight modules338such that the user is able to visually discern whether the controller212is in sleep mode MS or active mode MA.

The controller212may be configured to operate the backlight module338in first and second illumination states ISB1, ISB2. In some embodiments, the first illumination state ISB1may be defined by the absence of light emission and the second illumination state ISB2may be defined by light emission. It will be appreciated that the first and second illumination states ISB1, ISB2of the backlight module338could be defined in other ways sufficient to differentiate from each other. By way of non-limiting example, the first and second illumination states ISB1, ISB2could be defined by emission of light at different brightness levels (e.g., dimmed or changing between dimmed and brightened), in different colors, blinking patterns and the like. Other configurations are contemplated.

In the illustrated embodiment ofFIG.13, the controller212is shown in the sleep mode MS. During sleep mode MS, the controller212may be configured to operate the backlight module338in the first illumination state ISB1. In this representative embodiment, during the first illumination state ISB1, the backlight module338does not emit any light and thus no portion of the user interface204is illuminated. In response to receiving the a user input UI1generated by user engagement of any portion of the user interface204, the controller212is configured to switch from sleep mode MS to active mode MA.

In response to the controller212switching from sleep mode MS to active mode MA, the controller212switches the backlight module338from the first illumination state ISB1to the second illumination state ISB2. During the second illumination state ISB2, the backlight module338may be configured to at least partially illuminate one or more controls216,218,334or indicators330,332of the user interface204. In the illustrated embodiment ofFIG.14, the backlight module338is shown operating in the second illumination state ISB2such that the the direction input controls216, the battery indicator330, area light input control334, the speed indicator332, and the speed input controls218are all illuminated with backlighting.

As noted above, the one or more light modules210may include the area light module336that is disposed in communication with the controller212and configured to provide light to the surrounding area. As is depicted generically inFIGS.1-2, the illustrated area light module336is coupled to the carrier assembly148(e.g., to the cover186) and emits light EL in different directions relative to the seat section104(as well as to other components) as the patient transport apparatus100moves between the chair configuration CC (seeFIG.1) and the stair configuration SC (seeFIG.2). More specifically, the area light module336is arranged so as to emit light EL toward the floor surface FS when the patient transport apparatus100operates in the chair configuration CC (seeFIGS.1and12D; light emission is towards stairs as illustrated), and to emit light EL more upwardly when the patient transport apparatus100operates in the stair configuration SC (seeFIGS.2,12F, and12I). This configuration may advantageously direct emitted light above the second caregiver when transporting the patient down stairs ST with the patient transport apparatus100while still affording illumination of the surrounding area. In some embodiments, additional and/or alternative area light modules336could be provided to direct emitted light toward other areas, such as behind the patient transport apparatus100. To this end, one or more area light modules336could be coupled to the back section106(seeFIG.3) arranged to emit light toward the floor surface FS and/or stairs ST behind the patient transport apparatus100. Other configurations are contemplated.

Irrespective of the specific configuration and/or arrangement of the area light module336, the area light input control334may be configured to operate the area light module336in response to user engagement, and in some embodiments, the controller212may be configured to operate the area light input module344in a first illumination state ISD1and a second illumination state ISD2as to provide visual cues as to an operating state of the area light module336. The first illumination state ISD1may be defined by the absence of light emission. The area light input module344is shown in the first illumination state ISD1inFIGS.13-16. The second illumination state ISD2may be defined by light emission. The area light input module344is shown in the second illumination state ISD2inFIG.17. It will be appreciated that the first and the second illumination states ISD1, ISD2of the area light input module344could be defined in other ways sufficient to differentiate from each other. By way of non-limiting example, the first and second illumination states ISD1, ISD2could be defined by emission of light at different brightness levels (e.g., dimmed or changing between dimmed and brightened), in different colors, blinking patterns and the like. Other configurations are contemplated.

The controller212may be configured to automatically enter sleep mode MS in which the controller212initiates sleep mode MS based on the absence of user engagement with the user interface204. The automatic sleep mode MS may be disabled or deactivated in response to engagement of the activation input controls214, such as in order to prevent the controller212from entering automatic sleep mode MS while the patient transport apparatus100is ascending or descending stairs. The controller212may be configured to determine an absence of user engagement with the user interface204over a predetermined period. For example, the controller212may include a power countdown timer that is activated in response to the controller212switching to active mode MA and the activation input controls214being disengaged. The power countdown timer may be reset in response to engagement of any portion of the user interface204. In response to determining the absence of user engagement of the user interface204at the end of the predetermined period, the controller212may switch from the active mode MA to the sleep mode MS.

The controller212may set or otherwise determine the predetermined period based on an operating state of the area light module336. In response to the area light module336being OFF (i.e., the area light input module344is in the first illumination state ISD1), the controller212may set the time threshold to three minutes. In response to the area light module336being ON (i.e., the area light input module344is in the second illumination state ISD2), the controller212may set the timer threshold to fifteen minutes. While the examples of three minutes and fifteen minutes are provided, the controller212may be configured to the predetermined period or to other suitable times.

The battery indicator330may be configured to display a charge state of the battery206to the user. The state of charge of the battery206may be based on a voltage of the battery206. The battery indicator330may include a plurality of bars330A,330B,330C,330D or other indicia. As noted above, the one or more light modules210may include one or more battery light module346disposed adjacent or underneath to the battery indicator330. The controller212may be configured to operate the battery light module346in a first illumination state ISP1, a second illumination state ISP2, a third illumination state ISP2, a fourth illumination state ISP4, a fifth illumination state ISP5, and a sixth illumination state ISP6. In response to the controller212being in sleep mode MS, the controller212may operate the battery light module346in the first illumination state ISP1in which none of the bars330A,330B,330C,330D are illuminated (i.e., there is an absence of light emission). In response to the state of charge of the battery206falling within a first predetermined range, the controller212may operate the battery light module346in the second illumination state ISP2in which all four bars330A,330B,330C,330D are illuminated. The first predetermined range may be set from 76-100%. In response to the state of charge of the battery206falling within a second predetermined range, the controller212may operate the battery light module346in the third illumination state ISP3in which first, second, and third bars330A,330B,330C are illuminated. The second predetermined range may be set from 51-75%. In response to the state of charge of the battery206falling within a third predetermined range, the controller212may operate the battery light module346in the fourth illumination state ISP4in which the first and second bars330A,330B are illuminated. The third predetermined range may be set from 26-50%. In response to the state of charge of the battery206falling within a fourth predetermined range, the controller212may operate the battery light module346in the fifth illumination state ISP5in which the first bar330A is illuminated. The fourth predetermined range may be set to 15-25%. In response to the state of charge of the battery206falling within a fifth predetermined range, the controller212may operate the battery light module346in the sixth illumination state ISP6in which the first bar330A is illuminated in an oscillating manner (i.e., flashing manner). The fifth predetermined range may include a state of charge of less than 15%. While example ranges are provided for the first, second, third, fourth, and fifth predetermined ranges, the controller212may be configured to set the ranges to alternative ranges. Other configurations are contemplated.

As noted above, the one or more light modules210may include one or more direction light modules340arranged adjacent to or underneath the direction input controls216and disposed in communication with the controller212. The direction input controls216may include the first direction input control322and the second direction input control324. Here, the first direction input control322may be configured to select a drive direction of the motor188in order to ascend stairs. The second direction input control324may be configured to select a drive direction of the motor188in order to descend stairs. In some embodiments, the controller212may be configured to operate the direction light module340in a first illumination state ISL1, a second illumination state ISL2, and a third illumination state ISL3. The first illumination state ISL1may be defined by the absence of light emission. The second illumination state ISL2may be defined by oscillating light emission. The third illumination state ISL3may be defined by steady light emission. It will be appreciated that the first, second, and third illumination states ISL1, ISL2, ISL3of the direction light module340could be defined in other ways sufficient to differentiate from each other. By way of non-limiting example, the first and second illumination states ISL1, ISL2, ISL3could be defined by emission of light at different brightness levels (e.g., dimmed or changing between dimmed and brightened), in different colors, blinking patterns and the like. Other configurations are contemplated.

With reference back toFIG.13, the direction light module340is shown in the first illumination state ISL1(i.e., there is no light being emitted by the direction light module340). The controller212may operate the direction light module340in the first illumination state ISL1in order to communicate to the user that the patient transport apparatus100is operating in sleep mode MS.

In response to receiving the first user input UI1generated by user engagement of any portion of the user interface204, in addition to switching from the sleep mode MS to the active mode MA, the controller212may be configured to switch the direction light module340from the first illumination state ISL1to the second illumination state ISL2, as shown inFIG.14. The controller212may operate the direction light module340in the second illumination state ISL2in order to provide a visual prompt to the user that one of the direction input controls216needs to be selected.

In response to receiving a second user input UI2generated by user selection of one of the direction input controls216, the controller212may be configured to switch operation of the direction light module340from the second illumination state ISL2to the third illumination state ISL3. The third illumination state ISL3may provide a visual cue to the user that a direction has been selected. For example, inFIGS.15-17, the first direction input control322was selected by the user and is thus emitted with steady light during the third illumination state ISL3.

With reference toFIG.16, as previously discussed, the one or more speed input controls218may be configured to select between the plurality of drive speeds DS1, DS2, DS3of the motor188. The speed indicator332may be disposed adjacent to the one or more speed input controls218. The speed indicator332may be configured to display the selected one of the plurality of drive speeds DS1, DS2, DS3of the motor188to the user. Here, the one or more light modules210may include the speed light module348disposed adjacent or underneath the speed indicator332. The speed indicator332may include a plurality of bars332A,332B,332C or other indicia that are illuminated by the speed light module348in order to communicate to the user the selected one of the plurality of drive speeds DS1, DS2, DS3of the motor188.

The controller212may be configured to operate the speed light module348in a first illumination state ISS1defined by the absence of light emission. The controller212may be configured to operate the speed light module348in a second illumination state ISS2defined by light emission of a first bar332A. The controller212may be configured to operate the speed light module348in a third illumination state ISS3defined by light emission of first and second bars332A,332B. The controller212may be configured to operate the speed light module348in a fourth illumination state ISS4defined by the light emission of all three bars332A,332B,332C. It will be appreciated that the first, second, third, and fourth illumination states ISS1, ISS2, ISS3, and ISS4of the light module of the speed indicator332could be defined in other ways sufficient to differentiate from each other. By way of non-limiting example, the first and second illumination states ISS1, ISS2could be defined by emission of light at different brightness levels (e.g., dimmed or changing between dimmed and brightened), in different colors, blinking patterns and the like. Other configurations are contemplated.

The plurality of drive speeds DS1, DS2, DS3may correspond to predetermined speed settings (a specific RPM setting) stored in memory of the controller212. The plurality of drive speeds DS1, DS2, DS3may include a first drive speed DS1, a second drive speed DS2, and a third drive speed DS3. The first drive speed DS1corresponds to the lowest of the plurality of drive speeds DS1, DS2, DS3. The third drive speed DS3corresponds to the highest drive speed of the plurality of drive speeds DS1, DS2, DS3. The second drive speed DS2corresponds to a speed in between the first drive speed DS1and the third drive speed DS3. It will be appreciated that the forgoing are non-limiting, illustrative examples of three discreet drive speeds, and other configurations are contemplated, including without limitation additional and/or fewer drive speeds, drive speeds defined in other ways, and the like.

As noted above, the one or more speed input controls218may include a first speed input control326and a second speed input control328. The controller212may be configured to increase the selected speed to the next higher drive speed setting in response to the user engagement of the first speed input control326. For example, in response to receiving a third user input UI3generated by user engagement of the first speed input control326when the current selected drive speed is the first drive speed DS1, the controller212may set the current speed to the second drive speed DS2. The controller212may be configured to decrease the selected drive speed to the next lower drive speed setting in response to user engagement of the second speed input control328. For example, when the current selected drive speed is the second drive speed DS2, the controller212may set the current speed to the first drive speed DS1in response to user engagement of the second speed input control328.

The controller212may be configured to operate the speed light module348in one of the second, third, or fourth illumination states ISS2, ISS3, or ISS4based on the current drive speed setting DS1, DS2, DS3of the motor188. InFIGS.15-16, the current drive speed setting of the motor188is set to the first drive speed DS1. As such, the controller212operates the speed light module348in the second illumination state ISS2, as shown with the first bar332A of the speed indicator332is illuminated. InFIG.17, the speed light module348is shown in the third illumination state ISS3.

In some embodiments, the controller212may be configured to initially select the first drive speed DS1of the plurality of drive speeds DS1, DS2, DS3in response to user engagement of the direction input controls216following the change in operation from the sleep mode MS to the active mode MA. However, it is contemplated that the controller212may be configured alternatively, such as to initially select the second drive speed DS2or the third drive speed DS3of the plurality of drive speeds DS1, DS2, DS3.

The controller212may be configured to selectively permit operation of the motor188in response to receiving a fourth user input UI4generated by engagement of one of the activation input controls214(e.g., the first activation input control222or the second activation input control224). For example, the controller212may be configured to permit operation of the motor188in response to user engagement of at least one of the activation input controls214following user engagement of the direction input control216to drive the belt156in a selected drive direction. In another example, the controller212may be configured to permit operation of the motor188in response to user engagement of the activation input controls214within a predetermined period following engagement of the direction input control216. After the predetermined period following user engagement of the direction input control216has elapsed, the controller212may prevent operation of the motor188even when one of the activation input controls214is engaged. The controller212may also be configured to limit operation of the motor188in response to receiving the fourth user input UI4before receiving the second user input UI2generated by user selection of one of the direction input controls216.

The activation input controls214may be arranged between the first and second hand grip regions144,146in order to facilitate user engagement of the activation input controls214from either of the first and second hand grip regions144,146. As previously discussed, the activation input controls214include the first activation input control222and the second activation input control224. The first activation input control222may be disposed adjacent the first hand grip region144as to facilitate user engagement of the first activation input control222from the first hand grip region144. The second activation input control224may be disposed adjacent to the second hand grip region146as to facilitate user engagement of the second activation input control224from the second hand grip region146. Here, it will be appreciated that the user can engage either of the first and second hang grip regions144,146with one of their hands to support the patient transport apparatus100while, at the same, using that same hand to activate one of the first and second activation input controls222,224(e.g., reaching with their thumb).

The first activation input control222and the second activation input control224may be spaced apart by a predetermined distance (e.g., several inches) and are wired in parallel in some embodiments (not shown in detail). Here, as noted above, the one or more light modules210may include one or more activation light modules342arranged adjacent to or underneath the activation input controls214. The controller212may be configured to operate the activation light module342in a first illumination state ISA1, a second illumination state ISA2, and a third illumination state ISA3in order to provide visual cues to the user as to the current operating state of the patient transport apparatus100, in particular, the current operating state of the motor188.

The first illumination state ISA1can be defined by an absence of light emission. The second illumination state ISA2can be defined by light emission in a first color. The third illumination state ISA3can be defined by light emission in a second color that is different from the first color. It will be appreciated that the first, second, and third illumination states ISA1, ISA2, ISA3of the activation light module342could be defined in other ways sufficient to differentiate from each other. By way of non-limiting example, the first, second, and third illumination states ISA1, ISA2, ISA3could be defined by emission of light at different brightness levels (e.g., dimmed or changing between dimmed and brightened), in different colors, blinking patterns and the like. Other configurations are contemplated.

With reference back toFIGS.13-14, the activation light module342is shown in the first illumination state ISA1. The controller212may operate the activation light module342in the first illumination state ISA1in order to communicate to the user that the motor188is not ready to operate. The controller212may operate the activation light module342in the first illumination state ISA1when the controller212is in active mode MA and in response to determining that the direction input control216has not yet been engaged by the user.

With reference toFIG.15, the activation light module342is shown operating in the second illumination state ISA2. In some embodiments, the controller212may operate the activation light module342in the second illumination state ISA2in order to communicate to the user that the motor188is ready to be operated in the selected drive direction. For example, the controller212may switch the activation light module342from the first illumination state ISA2to the second illumination state ISA2in response to determining that the direction input control216has been engaged to select the drive direction of the motor188. The controller may be configured to continue to operate the activation light module342in the second illumination state ISA2when the activation input controls214are engaged.

With reference toFIG.4, the activation light module342is shown operating in the third illumination state ISA3. In some embodiments, the controller212may be configured to operate the activation light module342in the third illumination state ISA3in order to communicate to the user that one or more fault conditions associated with the patient transport apparatus100have been determined. For example, the controller212may be configured to switch from the first illumination state ISA1, to the second illumination state ISA2, and then to the third illumination state ISA3in response to determining one or more fault conditions associated with the patient transport apparatus100are present. The one or more fault conditions may be associated with any of the components of the patient transport apparatus100, such as the motor188, the battery206, and the like.

As noted above, the patient transport apparatus100may include one or more sensors208that generate one or more signals representative of a current state of the one or more components. The one or more sensors208may include a temperature sensor350configured to generate a temperature signal that is representative of the temperature of the motor188. The controller212may be configured to compare the temperature signal to a predetermined threshold in order to determine whether a temperature fault condition exists (e.g., the motor188has overheated). In response to the temperature signal exceeding the predetermined threshold, the controller may operate the activation light module342in the third illumination state ISA3to alert the user to the presence of a battery temperature fault condition.

In some embodiments, the controller212may be configured to perform a lockout function LF during user engagement of the activation input controls214. The lockout function LF may prevent changing the drive direction of the motor188in response to user engagement of the direction input control216until the activation input controls214are disengaged. For example, during user engagement of the activation input controls214, the controller212may be configured to perform the lockout function LF that prevents changing the drive direction of the motor188while the activation input controls214are engaged. In some embodiments, the controller212may be configured to determine a speed of the motor188, such as via a rotational speed sensor352(seeFIG.4; depicted schematically) and perform the lockout function LF until the activation input controls214are no longer engaged and the speed of the motor188is equal to or less than a predetermined threshold (e.g., not rotating)

With reference toFIG.17, the user is shown engaging the first activation input control222and the first speed input control326. Here, the controller212may be configured to permit the user to increase or decrease the drive speed via engagement with the one or more speed input controls218during engagement of at least one of the activation input controls214(e.g., while the patient transport apparatus100is ascending or descending stairs ST). The controller212may also be configured to permit operation of the area light input control334during engagement of the activation input controls214.

With reference toFIG.18, an exemplary method sequence500which may be performed by the controller212under certain use conditions of the patient transport apparatus100is depicted. As will be appreciated from the subsequent description below, this method sequence500merely represents an exemplary and non-limiting sequence of blocks to describe operation of certain light modules210in response to user engagement with the user interface204, and is in no way intended to serve as a complete functional block diagram of the control system202.

The exemplary method sequence500begins with the controller212operating in the sleep mode MS. At block504, the controller212determines whether the first user input UI1corresponding to user engagement with any portion of the user interface204has been received. If so, the controller212continues to block508; otherwise, the controller212waits at block504for the first user input UI1to be received. At block508, the controller212switches from the sleep mode MS to the active mode MA. At block512, in response to switching to the active mode MA, the controller212changes operation of the backlight module338from the first illumination state ISB1to the second illumination state ISB2. At block516, the controller212changes operation of the direction light module340from the first illumination state ISL1to the second illumination state ISL2.

At block520, the controller212determines whether the second user input UI2corresponding to user engagement with one of the direction input controls216has been received. If so, the controller212continues to block524; otherwise, the controller212waits at block520for the second user input UI2to be received. At block524, the controller212changes operation of the direction light module340from the second illumination state ISD2to the third illumination state ISL3. At block528, the controller212changes operation of the activation light module342from the first illumination state ISA1to the second illumination state ISA2. At block532, the controller212changes operation of the speed light module348from the first illumination state ISS1to the second illumination state ISS2.

At block536, the controller212determines whether the third user input UI3corresponding to user engagement with the first speed input control326has been received. If so, the controller212continues to block540; otherwise, the controller212continues to block552. At block540, the controller212changes operation of the speed light module348from the second illumination state ISS2to the third illumination state ISS3. At block544, the controller212determines whether the third user input UI3has been received for a second time corresponding to user engagement of the first direction input control322for a second time. If so, the controller212continues to block548; otherwise, the controller212continues to block552.

At block548, the controller212changes operation of the speed light module348to the fourth illumination state ISS4. At block552, the controller212determines whether the fourth user input UI4corresponding to user engagement with the activation input controls214has been received. If so, the controller212continues to block556; otherwise, the controller212waits at block552for the fourth user input UI4to be received. At block556, the controller212permits operation of the motor188in response to user engagement with the activation input controls214. While the exemplary method sequence500is shown as “starting” and “ending” inFIG.18for illustrative purposes, it will be appreciated that the controller212may instead return to block504. Furthermore, as noted above, the exemplary method sequence500described above and depicted inFIG.18is in no way intended to serve as a complete functional block diagram of the control system202, and other configurations are contemplated.

Several configurations have been discussed in the foregoing description. However, the configurations discussed herein are not intended to be exhaustive or limit the invention to any particular form. The terminology which 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.