Abstract:
A locking assembly is disclosed for use with a walker or a rollator having foldable side members. The locking assembly includes a locking pin movable between a first position in which the corresponding side member is held in a locked, unfolded state and a second position in which the side member is in an unlocked, folded state. A lock plate extends transversely to the longitudinal axis of the corresponding side member, and includes an aperture adapted to receive a locking end of the locking pin when the pin is in its first position. A lever is coupled to the locking pin such that when the lever is pivoted by upwardly applied pressure, the locking pin is moved from its first position to its second position to permit rotation of the corresponding side member to its folded state.

Description:
RELATED APPLICATIONS 
   This application is a continuation-in-part of U.S. patent application Ser. No. 10/397,972, now U.S. Pat. No. 6,886,575, the entire disclosure of which is expressly incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates generally to a locking assembly, and more particularly to a locking assembly for use with a foldable walker or a foldable rollator. 
   2. Related Art 
   Prior art locking mechanisms used in connection with foldable walkers have suffered from various drawbacks. The drawbacks stem from the limited manual dexterity of handicapped people. For example, some prior art assemblies are operated through use of a lever. At least one of these devices requires the user of the walker to push down on the lever to allow for the walker to be folded. However, certain people with limited dexterity may be incapable of exerting enough downward force to activate such a lever and thus will be unable to operate the locking assembly. Also, the lever handles of the prior art are often narrow. This presents additional problems for users having diminished manual dexterity. The narrowness of the handle makes finding and gripping the lever difficult. This is particularly true for users having a debilitating disease affecting their fingers, such as rheumatoid arthritis. 
   Still other prior art locking assemblies for walkers utilize a pin actuating plunger located remotely from the handles of the walker. Often, these prior art pin actuating plungers are positioned on a cross brace away from a walker&#39;s handles. In this configuration, a handicapped person with limited dexterity is required to release his/her grip on the handles in order to operate the pin actuating plunger mounted on the cross brace. However, during the period in which the handicapped user has released the handle, the handicapped user is unbalanced, creating a greater likelihood that the user may fall. Moreover, by positioning the pin actuating plunger on a cross brace, the handicapped user with limited dexterity is required to use two hands in order to fold each side brace, e.g., using one hand to depress the plunger while the other hand folds in the side brace. These problems described in connection with walkers are amplified with rollators, because the wheels of the rollator add another level of instability. 
   Based upon the foregoing, there is a need for a locking assembly for use with a foldable walker or a foldable rollator, which is both economical to manufacture and relatively easy to operate by people with limited dexterity. 
   SUMMARY OF THE INVENTION 
   Embodiments of the present invention overcome the above-described shortcomings of prior foldable walkers and rollators, and satisfy a significant need for a foldable walker and/or a foldable rollator that is relatively easy to configure between folded and unfolded positions by persons of limited dexterity. Accordingly to an exemplary embodiment of the present invention, a locking assembly is provided for use with a cylindrical member concentric with and rotatably mounted in a tubular member. The locking assembly may include a locking pin positioned parallel to a longitudinal axis of each of the two members and located external thereto. The locking pin is movable between a first position in which the two members are held in a locked state and a second position in which the members are in an unlocked state so that the two members are able to rotate in relation to each other. A lock plate is secured to one of the two members and extends transversely to the longitudinal axis thereof. The lock plate has an aperture adapted to receive a locking end of the locking pin when the pin is in the first position. A lever assembly is provided for moving the locking pin from its first position to its second position to permit rotation of the cylindrical member in relation to the tubular member. This lever assembly includes a housing member attached to another of the two members, and an actuating lever having a force-applying handle end and a housing attach end. A portion of the actuating lever is operatively connected to the locking pin. The housing attach end of the actuating lever is pivotally received by the housing member so that when an upward force is applied to the handle end, the actuating lever pivots with respect to the housing member and moves the locking pin to its second position thereby allowing the two members to be movable relative to each other. 
   According to another exemplary embodiment of the invention, a foldable walker is provided having a pair of side frames each of which has a substantially vertical front tubular leg. The foldable walker further includes a cross brace having a pair of substantially vertical end sleeves in which the tubular legs are concentrically contained so that the tubular legs are rotatable between a locked state and an unlocked state. 
   A locking assembly is also provided and is associated with each tubular leg. The locking assembly includes a first body portion having a first bore through which extends the tubular leg along a first longitudinal axis. A fastener rigidly connects the first body portion to the tubular leg, the fastener extending transversely to the first longitudinal axis and into both the first body portion and the tubular leg. A locking pin is movable between a first position in which the tubular leg and sleeve are in a locked state and a second position in which the tubular leg and sleeve are in an unlocked state. A second body portion rigidly connected to the first body portion has a second bore through which extends the locking pin along a second longitudinal axis wherein the first and second longitudinal axes are in relatively parallel position. A lock plate is rigidly connected to the end sleeve and extends transversely to the first and second longitudinal axes. The lock plate has an aperture which is adapted to receive a locking end of the locking pin when the locking pin between its first and second positions, an actuating lever is provided which has a force applying handle end and a body attach end operatively connected to at least one of the first and second body portions. A portion of the actuator lever between the force applying handle end, the actuating lever points with respect to the body portions and moves the locking pin from its first position to its second position, thereby allowing the tubular leg to be moved relative to the corresponding end sleeve. 
   According to another embodiment of the present invention, a foldable rollator is provided and includes a locking assembly for selectively locking side frames of the rollator. Each of the side frames includes a substantially vertical front tubular leg, and a locking mechanism in accordance with the present invention which is associated with each side frame. A cross-brace having a pair of substantially vertical end sleeves is provided, wherein tubular legs of the side frames are contained within the end sleeves and are pivotable with respect thereto. The locking assembly allows the side frames to be rotated between a locked state and an unlocked state. 
   The present invention also provides a method for folding a foldable rollator. The method comprises the steps of holding the hand grips of the first and second side frames; grasping first and second handles of the first and second locking assemblies; pulling the first and second handles up towards the hand grips to unlock the first and second locking assemblies; and rotating the first and second side frames toward the cross brace and into a folded position. Further, the method can include the step of unfolding the rollator for use, comprising rotating the first and second side frames away from the cross brace into locked positions substantially perpendicular to the cross brace. 
   Objects and advantages of the present invention will become apparent from reading the following description of the invention wherein reference is made to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete understanding of the system and method of the present invention may be obtained by reference to the following Detailed Description when taken in conjunction with the accompanying Drawings wherein: 
       FIG. 1  is a perspective view of a foldable walker with one side frame in its folded position and a second side frame in its unfolded position; and 
       FIG. 2  is an enlarged exploded perspective view of the locking assembly portion for the foldable walker of  FIG. 1 . 
       FIG. 3  is a perspective view of a foldable rollator, with one side frame in a folded position and a second side frame in an unfolded position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present invention will now be described more fully hereinafter with reference to the accompanying drawings in which an exemplary embodiment of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. 
   Referring now to the drawings wherein the showings are for purposes of illustrating an exemplary embodiment of the invention only and not for purposes of limiting same,  FIG. 1  shows a walker  10  which includes a pair of spaced side frames  12  and  14  and a cross brace  16  for connecting the two side frames. Side frames  12  and  14 , and cross brace  16  can be made from a lightweight and sturdy metallic material such as conventional aluminum or steel. Preferably, the metallic material of the side frames and cross brace is tubular in nature to reduce the weight of the walker. Since the right side frame  14  is identical to left side frame  12 , the description of the two is identical. Thus only the left side frame  12  will be described in detail herein. 
   The left side frame  12  includes a top substantially horizontal support arm joining substantially vertical front and rear legs  20  and  22 . A non-sliding hand grip  24  fits snugly around the horizontal support arm  18 . The hand grip  24  is preferably formed from a suitable conventional polymeric material. 
   Releasably connected to the ends of the front and rear tubular legs  20  and  22  are front and rear telescoping tubular leg extensions  26  and  28 , respectively. These telescoping extensions allow the walker to be adjusted in accordance with the height of the individual user. The telescoping extensions are connected to the legs using a snap button and corresponding biasing spring (not shown in the drawings). Because use of snap buttons and biasing springs to provide for walker legs having adjustable lengths is very well known in the art, details of the snap buttons and biasing springs will not be described for reasons of simplicity. 
   A crutch tip  50  is adapted to fit on the ground-engaging ends of the tubular leg extensions  26 ,  28  to prevent sliding movement between the walker  10  and the ground. In contrast to the metallic nature of the cross brace  16  and the side frames  12  and  14 , crutch tips  50  are preferably made from a suitable conventional thermoplastic material. 
   A side brace  54  is connected between legs  20  and  22  of each side frame  12  and  14  to prevent a spreading of the legs  20  and  22  of the walker  10  when the walker  10  is supporting the weight of the user. 
   The cross brace section  16  comprises a cross bar connected to a pair of substantially vertical end sleeves  60  and  62  which snugly embrace and surround intermediate portions of the front legs  20  of side frames  12  and  14 , respectively. 
   For convenience of handling and storage, each side frame  12  and  14  may be folded inwardly relative to the cross brace  16  as shown by arrow A in  FIG. 1  with respect to side frame  12 . Yet, to make the walker stable during use, the side frames  12  and  14  are required to be locked to the end sleeves  60  and  62 , respectively, to prevent rotation when in the operative, open position as shown in  FIG. 1  with respect to side frame  14 . 
   Accordingly, a novel locking assembly  70  cooperates with each of the front legs  20  and its associated end sleeves  60 ,  62  to lock the walker in its operative position, as shown in  FIG. 1  for side frame  14 , or to enable the walker to be relatively easily folded into its folded, storage position, as shown in  FIG. 1  for side frame  12 . The locking assembly will be described only with respect to right side frame  14  and end sleeve  62 . However, it should be appreciated that an identical locking assembly is provided for left side frame  12  and end sleeve  60 . 
     FIG. 2  illustrates the locking assembly  70  in an exploded perspective form. The locking assembly  70  may include a locking pin  72  formed of a suitable metallic material extending through a pin bore  74  of a pin housing  76 . A connecting rod  86  engages with a portion of locking pin  72  and is utilized to control the position of locking pin  72  within pin bore  74 . For example, connecting rod  86  engages with a portion of locking pin  72  somewhat proximal to end  78  thereof. It is understood that connecting rod  86  may engage with another portion of locking pin  72 . In the exemplary embodiment shown in  FIG. 2 , connecting rod  86  is pivotally connected to locking pin  72 . 
   A locking end  88  of locking pin  72  is adapted to snugly extend through an opening  90  of a lock plate  92  to lock front leg  20  and end sleeve  60  together and retain the walker in the operative, open position. It will be appreciated that the lock plate  92  is fixedly attached, such as by welding, to the outer periphery of end sleeve  60  and extends substantially normal thereto. A biasing spring  94  may surround some or all of the locking pin  72  within the pin bore  74 . The spring has a first end  96  which may sit on a pin shoulder seat  98  and a second end  100  which abuts an inner shoulder of the pin bore  74 . The biasing spring  94  normally urges the pin locking end  88  into the lock plate opening  90  when they are aligned as shown in  FIG. 2 . 
   The pin housing  76  is generally cylindrical having a longitudinal bore  104  extending therethrough and adapted to receive the front leg  20 . Pin housing  76  may include a recess  106  defined along an upper edge of pin housing  76  and dimensioned to receive a pivot extension. Recess  106  cooperates with the pivot extension to provide a fulcrum about which an actuating lever  84  may rotate. Fasteners in the form of pop rivets (not shown) or the like may extend through pin housing  76  and the side frame so as to provide a rigid connection there between. It should be appreciated that the locking assembly prevents any upward sliding motion of the cross brace  16 . 
   The actuating lever  84  may include pivot extension  112  that extends from a housing attach end  122  of actuating lever  84 . Pivot extension  112  engages with recess  106  of pin housing  76  so as to provide a fulcrum of actuating lever  84 , as described above. Pivot extension  112  may, for example, have a bulbous shape and be capable of movement within recess  106  so that actuating lever  84  may also have a transverse bore  118  which is aligned with the housing bore  104  to accommodate the front leg  20 . The bore  118  is sized or otherwise configured to allow actuating lever rotation about the previously described fulcrum while the tubular front leg  20  is extended there through. 
   Connecting rod  86  may be connected between actuating lever  84  and locking pin  72 . An end of connecting rod  86  may be pivotally attached to a portion of actuating lever  84  between handle portion  120  and housing attach end  122  of actuating lever  84 . To unlock front leg  20  from end sleeve  60 , locking pin  72  must be pulled upwardly so that the locking end  88  thereof is completely removed from the lock plate opening  90 . This action is accomplished by conveniently and efficiently pulling upwardly, using finger-applied pressure, on handle portion  120  of the actuating lever  84 . This, in turn, causes connecting rod  86  to be pulled in a substantially upward direction so as to raise the locking pin  72  within pin bore  74 . Once the locking pin  72  is completely withdrawn from the lock plate opening  90 , front leg  20  may then be rotated by the patient using hand-applied pressure onto hand grip  24  of the side frame  14  until the side frame  14  is in the folded position. In this way, the right side frame  14  can be folded substantially against the cross brace  16 , since the locking end  88  of locking pin  72  will merely slide over the flat surface of the lock plate  92  and not be fixed thereto. 
   As illustrated in  FIG. 1 , the handle portion  120  of actuating lever  84  extends beneath hand grip  24 . Because of the proximity between the handle portion  120  and hand grip  24 , a handicapped user need only to extend one or more of his/her fingers so as to engage with the handle portion  120  while the palm and thumb of the same hand continue to engage with the hand grip  24 . During this time, the user of the walker may continue to use the walker as a support device and will be less likely to lose his/her balance when folding the walker. When the handle portion  120  is manipulated, the corresponding side frame may be folded inwardly while the user&#39;s hand continues to grasp the hand grip  24  of the side frame. In this way, the locking assembly  70  may be actuated and the corresponding side frame may be placed in the folding position without the user having to release his/her grip on hand grip  24 . 
   Thus, it is very easy and convenient for the handicapped person to release the locking pins  72  and rotate the side frames  12  and  14  from their open operable positions to their folded storage positions. The folded walker can easily be unfolded by rotating the side frames  12 ,  14  outwardly until the respective locking pin  72  snaps into the respective lock plate opening  90 . 
     FIG. 3  shows a rollator  210  which includes a pair of spaced side frames  212  and  214  and a cross brace  216  for connecting the two side frames. Side frames  212  and  214 , and cross brace  216  can be made from a lightweight and sturdy metallic material such as conventional aluminum or steel. Preferably, the metallic material of the side frames and cross brace is tubular in nature to reduce the weight of the rollator. The right side frame  214  is identical to left side frame  212 . 
   The left side frame  212  includes a top substantially horizontal support arm  218  joining substantially vertical front and rear legs  220  and  222 . A non-sliding hand grip  224  fits snugly around the horizontal support arm  218 . The hand grip  224  is preferably formed from a suitable conventional polymeric material. 
   Releasably connected to the ends of the front and rear tubular legs  220  and  222  are front and rear telescoping tubular leg extensions  226  and  228 , respectively. These telescoping extensions allow the rollator to be adjusted in accordance with the height of the individual user. The telescoping extensions can be connected to the legs using a snap button and corresponding biasing spring (not shown in the drawings), which are well known in the art. 
   Forward wheels  250  are attached to the ends of the tubular leg extensions  226 , and are pivotable with respect thereto to allow a user to steer the rollator  210  in any desired direction. Rear wheels  251  are attached to the ends of the tubular leg extensions  228 , and could be fixedly or pivotally attached thereto. The rollator  210  could be provided with forward wheels only, i.e., no rear wheels, as is known in the art. A wheel locking device  253  could be provided on the wheels  251  to prevent movement of the rollator  210 . 
   A side brace  254  is connected between legs  220  and  222  of each side frame  212 ,  214 . The side brace  254  reinforces the side frame  212  to prevent spreading of the legs  220  and  222  of the  210  when the rollator  210  is supporting the weight of the user. 
   The cross brace section  216  comprises a cross bar connected to a pair of substantially vertical end sleeves  260  and  262  which snugly embrace and surround intermediate portions of the front legs  220  of side frames  212  and  214 , respectively. 
   For convenience of handling and storage, each side frame  212  and  214  may be folded inwardly relative to the cross brace  216  as shown in  FIG. 3  with respect to side frame  212 . Yet, to make the rollator stable during use, the side frames  212  and  214  are locked to the end sleeves  260  and  262 , respectively, to prevent rotation when in the operative, open position as shown in  FIG. 3  with respect to side frame  214 . 
   The locking assembly  270 , which can be the same as shown in  FIG. 2  and described herein, cooperates with each of the front legs  220  and its associated end sleeves  260 ,  262  to lock the rollator in its operative position, as shown in  FIG. 3  for side frame  214 , or to enable the rollator to be relatively easily folded into its folded, storage position, as shown by arrow B in  FIG. 3  for side frame  212 . The locking assembly can be actuated by a user extending one or more fingers to engage the handle portion  284  to pull up the handle to unlock the side frames  212 ,  214  and permit them to pivot to a flat position against the cross brace  216 . 
   The present invention also provides a method for folding a foldable rollator. The method comprises the steps of holding the hand grips of the first and second side frames; grasping first and second handles of the first and second locking assemblies; pulling the first and second handles up towards the hand grips to unlock the first and second locking assemblies; and rotating the first and second side frames toward the cross brace and into a folded position. Further, the method can include the step of unfolding the rollator for use, comprising rotating the first and second side frames away from the cross brace into locked positions substantially perpendicular to the cross brace. When the handles are pulled upward, the locking pins are removed from the locking plates of the first and second assemblies by the actuating levers to unlock the assemblies 
   The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.