Abstract:
An device designed to assist in changing a vehicle wheel is herein disclosed. The ergonomically-designed device is fabricated of a variety of strong, rigid materials (e.g. steel) to provide the durability required by the nature of its usage. The three main sub-assemblies of the present invention include a frame assembly, a seat assembly, and a wheel support assembly. The tubular frame assembly rides on casters and preferably includes a cross-member on which the elements of the wheel support assembly are mounted. A frame-mounted seat provides the user with an ergonomic means to position himself/herself for placing the wheel on, or removing it from, the axle hub. A tray attached to the tubular frame assembly provides an area where the user&#39;s tools or the wheel&#39;s lug nuts may be temporarily stored.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to devices utilized in changing the wheels of automobiles and light trucks and, more particularly, to an improved design for a device possessing the means to support a vehicle wheel (i.e. the combination, or assembly, of a rim and a tire) off of the ground (1) during installation on, or removal from, an axle hub, and (2) while transporting the wheel from/to the vehicle for replacement, repair, etc.  
           [0003]    2. Description of the Background  
           [0004]    The wheels utilized on automobiles and light trucks can be quite heavy. In the course of a typical workday, individuals employed in companies specializing in wheel/tire sales (i.e. installation) or maintenance are repeatedly called upon to remove and/or install, as well as transport about the facility, a significant number of vehicle wheels. This presents the owners of those businesses with certain ergonomic challenges that must be overcome to maintain a safe, healthy working environment (e.g. avoidance of worker injuries due to lifting and/or repetitive motion syndrome).  
           [0005]    The present inventors are not the first to notice this deficiency and devices designed to assist with the changing of automobile and light truck wheels are not unknown in the art. Variations on the theme are found in U.S. Pat. No. 3,828,955 to Harkey, U.S. Pat. No. 3,847,294 to Davenport, U.S. Pat. No. 4,256,430 to Pugel, U.S. Pat. No. 4,872,694 to Griesinger, and U.S. Pat. No. 5,348,438 to Roberts. The various designs include features such as a foot plate (e.g. Griesinger &#39;694, Roberts &#39;438), a knee plate (e.g. Roberts &#39;438), or a seat (e.g. Pugel 430) so that the operater may use his/her body weight to pivot the device as a wheel is on- or off-loaded. One device even provides the ability to accommodate more than one wheel at a time (e.g. Davenport &#39;294).  
           [0006]    U.S. Pat. No. 3,828,955 to Harkey discloses a tire changing tool that includes a lever plate having a flat surface terminating at an upturned lip for supporting a tire, a solid handle extending upwardly from the lever plate, and a pair of wheel assemblies supporting the lever plate with soft rubber tires designed to offer some resistance to rotation such that the assembly will not freely roll.  
           [0007]    U.S. Pat. No. 3,847,294 to Davenport discloses a dual wheel remover which is mounted on a combination of fixed and swivel type casters and possesses an adjustable tilting feature that allows wheels to be easily removed from a vehicle and securely transported without the need for the operator of the assembly to physically handle the wheels.  
           [0008]    U.S. Pat. No. 4,256,430 to Pugel discloses a wheel change mechanism comprising a base member which is movable along a support surface, wheel support members that extend from one end of the base member, and a seat positioned at the opposite end of the base member for pivoting the base member when a force is exerted thereon.  
           [0009]    U.S. Pat. No. 4,872,694 to Griesinger discloses a wheel mounting device adapted to lift and position a wheel by means of two horizontal parallel rollers, two vertical parallel rollers, a caster-mounted main-frame plate with extensions forming a triangle, and a foot plate positioned at the apex of the triangle.  
           [0010]    U.S. Pat. No. 5,348,438 to Roberts discloses a vehicle wheel changing aid that includes a rocker base having an operator end, a wheel receiving end, a bottom facing pivot surface adapted to contact the ground as the rocker base is pivoted, a plurality of spaced apart rollers for use in accurately aligning the wheel lug openings with the lugs on the axle hub, and a knee/foot bearing pad positioned towards the operator end of the base that permits a wheel to be raised or lowered from the axle hub by application of the operator&#39;s knee/foot.  
           [0011]    However, the prior art still offers room for improvement. All of the aforementioned devices introduce some degree of vertical tilt with respect to the vehicle which makes it more difficult to remove the tire from the lugs of the wheel hub. Moreover, none of the foregoing patents address the ergonomic issues required for long-term, repetitive use in a commercial environment. Therefore, there exists a need for a device possessing improved, adjustable means for lifting a vehicle wheel while providing the comfort and utility required for long-term, repetitive use.  
         SUMMARY OF THE INVENTION  
         [0012]    It is, therefore, the primary object of the present invention to provide an improved device to assist the changing of a vehicle wheel that is designed to lift the wheel vertically from the lugs of the axle hub, without any degree of tilting, during the removal/replacement process.  
           [0013]    It is another object to provide an improved device to assist the changing of a vehicle wheel that possesses a wheel support assembly that can be adjusted to accommodate wheels of different sizes/diameters.  
           [0014]    It is yet another object to provide an improved device to assist the changing of a vehicle wheel that includes a place for the operator to temporarily store a plurality of lug nuts in addition to his/her tools.  
           [0015]    It is still another object to provide an improved device to assist the changing of a vehicle wheel that possesses a simple, ergonomically-correct, durable design that can be manufactured economically.  
           [0016]    In accordance with the above objects, one embodiment of the present invention is an ergonomically-designed device fabricated of a variety of strong, rigid materials (e.g. steel) to provide the durability required by the nature of its usage. The three main sub-assemblies of the present invention include a frame assembly, a seat assembly, and a wheel support assembly. The tubular frame assembly rides on casters and preferably includes a cross-member on which the elements of the wheel support assembly are mounted. A frame-mounted seat provides the user with an ergonomic means to position himself/herself for placing the wheel on, or removing it from, the axle hub. A tray attached to the inside of the tubular frame assembly creates an area where the user&#39;s tools or the wheel&#39;s lug nuts may be temporarily stored. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments and certain modifications thereof when taken together with the accompanying drawings in which:  
         [0018]    [0018]FIG. 1 is a top perspective view of a device  15  designed to assist the changing of a vehicle wheel according to a first embodiment of the present invention.  
         [0019]    [0019]FIG. 2 is a front perspective view of the device  15  shown in FIG. 1.  
         [0020]    [0020]FIG. 3 is a side perspective view of the device  15  shown in FIGS. 1 and 2.  
         [0021]    [0021]FIG. 4 is a top, close up view of the adjustable wheel support roller assembly  70  as shown in FIG. 1.  
         [0022]    [0022]FIG. 5 is a side perspective view of the device  15  of FIGS.  1 - 3  shown supporting a wheel  100  that has just been removed from (or, conversely, that is just about to be placed on) an axle hub  110 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]    [0023]FIGS. 1, 2, and  3  show, respectively, top, front, and side perspective views of the device  15  to assist the changing of a vehicle wheel according to a first embodiment of the present invention. The three main sub-assemblies of the present invention include a frame assembly  20 , a seat assembly  40 , and a wheel support assembly  60 .  
         [0024]    The frame assembly  20  is preferably constructed of steel and/or another strong, rigid material. The frame assembly includes two divergent square tubular side members  22  joined at their apex, one square tubular cross-member  24  spanning the two side members  22 , two square tubular extension members  25  protruding forwardly from the ends of the cross-member  24 , three commercially available swivel-type casters  26 , and one triangular sheet metal tray  28 .  
         [0025]    The side members  22  and the cross-member  24  are fixedly connected in a triangular configuration such as shown in FIG. 1. The extension members  25  are fixedly attached at both ends of the cross-member  24  perpendicular to the cross-member  24 . One of the casters  26  is fixedly attached to the underside of the side members  22  proximate the point where the members  22  are joined. The other two casters  26  are fixedly attached to the underside of the distal ends of extension members  25 . The tray  28  is fixedly attached to the inside surfaces of the side members  22 . The triangular tray provides the user with a place to temporarily store lug nuts and/or his/her tools. It should be understood that frame configurations other than the triangle of FIG. 1 may be utilized.  
         [0026]    The seat assembly  40  further comprises two upwardly-directed support legs  42  and a seating surface  44 . The seat support legs  42  are preferably fabricated of steel or another strong, rigid material. The bottom end of each support leg  42  is fixedly attached to the top surface of the frame assembly  20  proximate the apex where the side members  22  are joined. The seating surface  44  may be a commercially available, vinyl covered, foam cushioned, seat assembly that is fixedly attached to the top ends of the support legs  42 . The length of the support legs  42  is such that the seating surface  44  to allow the user to both (1) propel the device  15  with his/her feet while in a seated position, or (2) push the device  15  via placement of his/her hands on the seating surface  44  while standing or walking. Alternatively, the seat assembly  40  may be configured such that its height is adjustable within an ergonomically appropriate range.  
         [0027]    The wheel support assembly  60  further comprises a vertical support member  62 , vertical travel load bearing assembly  64 , a lift control lever  66 , a horizontal lift member  68 , and two adjustable wheel support roller assemblies  70 .  
         [0028]    The vertical support member  62  and the horizontal lift member  68  are preferably constructed of square tubular steel stock (or another strong, rigid material). The vertical support member  62  is fixedly attached to the frame&#39;s cross-member  24  in a vertical orientation. The lift member  68  includes two vertically oriented holes  67  in its top surface (positioned proximate each of its ends).  
         [0029]    The vertical travel load bearing assembly  64  comprises two side plates  82  and two commercially available roller assemblies  84 . The side plates  82  are preferably constructed of steel (or another strong, rigid material) bar stock. The center shafts  86  of the roller assemblies  84  are fixedly attached proximate the ends of the plates  82  such that the shafts  86  are parallel and the space left between the surfaces of the rollers  84  is equivalent to the width of the vertical member  62 . When installed in the fully assembled device  15 , the load bearing assembly  64  straddles the vertical member  62  with opposing rollers  84  in rolling contact with the member  62  and the plates  82  fixedly connected to the top surface of the lift member  68 , such that any movement of the member  68  is either straight up, or straight down.  
         [0030]    The lifting assembly  66  comprises a handle  91 , a lift lever  92 , a shaft  93 , a bearing assembly  94 , a bearing support bracket  95 , a lower link  96 , an upper link  97 , an upper link bracket  98 , and two link pins  99 . The lift lever  92  and the shaft  93  are preferably constructed of steel (or another strong, rigid material), round bar stock. The bearing support bracket  95 , the upper link bracket  98 , and the links  96 ,  97  are preferably constructed of steel (or another strong, rigid material), rectangular bar stock.  
         [0031]    The commercially available handle  91  is fixedly attached at one end of the lift lever  92 . The other end of the lever  92  is fixedly attached to one end of the shaft  93  such that the center axis of the lever  92  is perpendicular to the center axis of the shaft  93 . The shaft  93  extends through and is rotatably supported by the commercially available bearing assembly  94 . The bearing assembly  94  is fixedly attached to the bearing support bracket  95  which is, in turn, fixedly attached to the bottom surface of the cross-member  24 . The other end of the shaft  93  is fixedly attached to one end of the lower link  96 . The other end of the lower link  96  is rotatably connected to one end of the upper link  97 . The other end of the upper link  97  is rotatably connected to the upper link bracket  98  which is, in turn, fixedly attached to the bottom surface of the lift member  68 . The rotating connections between the links  96 ,  97  and the bracket  98  are facilitated by commercially available link pins  99 .  
         [0032]    Vertical movement of the lift member  68  is provided by the lifting assembly  66  when the user exerts force on the lever  92 . Force exerted on the lever  92  results in rotation of the shaft  93 . Rotation of the shaft  93  causes the lower link  96  to pivot about the axis running through the center of the shaft  93 . Due to the fixed connection of the support bracket  95  on the frame assembly  20 , and the fixed connection of the upper link bracket  98  on the lift member  68 , coupled with the limitations on the movement of the lift member  68  (i.e. up or down along a vertical axis only, imposed by the load bearing assembly&#39;s  64  contact with the vertical member  62  and connection to the lift member  68 ), any pivoting, or angular rotation, of the lower link  96  causes a corresponding angular rotation of the upper link  97 . Any angular rotation of the links  96 ,  97  changes the effective length of the links  96 ,  97  along the vertical axis of movement of the lift member  68  causing a change in the elevation of the lift member  68  and anything attached to, or supported by it (e.g. a wheel). The elevation of the lift member  68  may be anything between the “up” position established when the links  96 ,  97  are aligned with the vertical axis (see FIG. 2), and the “down” position created when the links  96 ,  97  are oriented at angles approximately 45° from the vertical axis.  
         [0033]    In contrast to that provided in the prior art (i.e. a lifting motion accompanied by some tilting of the wheel), this novel wheel support assembly  60  incorporates a straight, vertical lifting motion. There is no tilting of the wheel during the lifting procedure.  
         [0034]    [0034]FIG. 4 is a close up view of the adjustable wheel support roller assembly  70  as shown in FIG. 1. Each adjustable wheel support roller assembly  70  includes an adjustment bar  72 , a commercially available roller assembly  74 , and a commercially available indexing plunger assembly  76 . The adjustment bar  72  is preferably constructed of steel (or another strong, rigid material), square tubular stock and includes a plurality of regularly spaced holes  73  thorugh its top surface. The roller assembly  74  is fixedly attached at one end of the adjustment bar  72  such that the center axis of the roller  74  is perpendicular to the center axis of the bar  72 , as well as being perpendicular to the center axes of the plurality of holes  73 .  
         [0035]    The bar  72  is slidably engaged with the horizontal lift member  68  such that the amount of interference, or overlap, between the two can be adjusted via an indexing plunger assembly  76  and the holes  67 ,  73 . The plunger assembly  76  is fixedly attached to the top surface of the lift member  68  such that the spring-loaded, internal plunger  77  (see FIG. 2) protrudes through the lift member hole  67  and one of the adjustment bar holes  73 . To change the position of the bar  72  relative to the lift member  68 , the user pulls on the internal plunger  77  to remove it from the adjustment bar hole  73 . Once the plunger  77  is clear of the hole  73 , the bar  72  is slid inward, or outward, to align another of the plurality of holes  73  in the bar  72  with the hole  67  located in the lift member  68 . The plunger  77  is then released to snap back into the holes  67 ,  73 . Adjustment of the position of the two wheel support assemblies  70 , thereby increasing or decreasing the distance between the two roller assemblies  74  (see dimension “D” shown in FIG. 1), allows the device  15  to safely and ergonomically support wheels of varying sizes.  
         [0036]    [0036]FIG. 5 illustrates the use of the device  15  designed to assist the changing of a vehicle wheel according to a first embodiment of the present invention. The device  15  is shown supporting a wheel  100  that has just been removed from (or, conversely, that is just about to be placed on) an axle hub  110 . The wheel  100  was removed from the axle hub  110  by completing the following series of steps:  
         [0037]    (1) With the lifting assembly  66  in the “down” position, the roller assemblies  74  were adjusted, via the process discussed with respect to FIG. 4, in order to appropriately position them to support the wheel  100 .  
         [0038]    (2) The plurality of lug nuts  114  were removed from the matching plurality of lugs  112  and placed for temporary storage in the integral tool tray  28 .  
         [0039]    (3) The lifting assembly  66  was utilized to drive the wheel support assembly  60  upward (i.e. the user exerted the required amount of force on the lift lever  92 ). The upward movement of the horizontal lift member  68 , the wheel support roller assemblies  70  (i.e. the roller assemblies  74 ), and the wheel  100  transferred the weight of the wheel  100  from the lugs  112  to the device  15 .  
         [0040]    (4) While continuing to exert the required force on lever  92 , the user caused the device  15  to travel in the direction of arrow  120  such that the wheel  100  was moved clear of the axle hub  110  and the lugs  112 .  
         [0041]    (5) The user lowered the lifting assembly  60  by gradually reducing the amount of force being exerted on the lever  92  until the lifting assembly  66  returned to the “down” position.  
         [0042]    Once Step (5) has been completed, the device  15  and the wheel  100  may be easily moved as a unit by the user to complete any necessary tire repair/replacement processes.  
         [0043]    The wheel  100  can be placed on the axle hub  110  by completing the following series of steps:  
         [0044]    (1) The user raises the lifting assembly  60  by exerting the required amount of force on the lever  92  until the lifting assembly  66  achieves the appropriate “up” position (i.e. the height of the center of the wheel  100  matches that of the center of the axle hub  110 /lugs  112 ).  
         [0045]    (2) The user moves the device  15  in the direction of arrow  125  such that the wheel  100  engages the axle hub  110  and the lugs  112 . As the wheel  100  approaches the hub  110  and the lugs  112 , the roller assemblies  74  allow the user to slightly rotate the wheel  100  to precisely align the the clearance holes in the wheel&#39;s rim with the lugs  112 .  
         [0046]    (3) The plurality of lug nuts  114  are taken from their temporary storage location in the integral tool tray  28  and replaced on the matching plurality of lugs  112 .  
         [0047]    (4) The lift assembly  66  is lowered to the “down” position (i.e. the user gradually reduces the force being exerted on the lift lever  92 ). The downward movement of the horizontal lift member  68 , the wheel support roller assemblies  70  (i.e. the roller assemblies  74 ), and the wheel  100  transfers the weight of the wheel  100  from the device  15  to the lugs  112 .  
         [0048]    Having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth in the appended claims.