Abstract:
An apparatus for the repair or maintenance of a vehicle is provided which facilitates the removal of a wheel, wheel rim, brake rotor, brake drum or the like, when these become seized or fused onto the wheel hub of the vehicle. The wheel pulling apparatus provides a pull plate to pull on, for example, a brake drum, and a push plate which acts to directly or indirectly push on the wheel studs of the vehicle. A simple, easy to use wheel pulling apparatus is provided.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to the field of vehicle repair and maintenance, and in particular, relates to a device for the removal of wheels, brake drums, brake rotors, and the like, from a vehicle.  
         BACKGROUND OF THE INVENTION  
         [0002]    During the repair or maintenance of a vehicle, including trucks, automobiles and the like, it is frequently necessary to remove the wheels, brake rotors and/or brake drums. However, the tolerances between these devices is very small. For example, the clearance between the inner wheel rim and the wheel hub are typically on the order of only several thousands of an inch. Similarly, the clearance between a brake drum or brake rotor and the wheel hub is also very small. Because of these small tolerances and because the wheel hub assembly bears the weight of the vehicle, extended use of the vehicle can frequently cause the inner wheel rim, the brake drum, or the brake rotor, to become essentially fused or seized on the wheel hub.  
           [0003]    Once a wheel, for example, is seized on the wheel hub, it can be very difficult to remove the wheel from the vehicle by hand. The common practice in the vehicle repair industry is to have a mechanic hoist the vehicle and hammer on the seized wheel, from the inside, until the wheel becomes loose enough to remove.  
           [0004]    This method can, however, cause damage to the rim, the brake drum, the brake rotor, or other parts of the vehicle during hammering. Further, this operation can take an unacceptable amount of time to release the seized part. Yet further, the safety of the mechanic can be jeopardized when hammering a wheel part while under the vehicle.  
           [0005]    Still further, if the vehicle should need repair while traveling, such as for example, caused by having a flat tire, it can often be excessively difficult to remove the seized part by hand. Further, hammering of the part with a heavy object is not generally an acceptable option because of the limited space under the vehicle created by lifting the vehicle with a small manual vehicle jack.  
           [0006]    In order to address these problems, the prior art provides for a number of different devices to assist in this type of vehicle repair, and to assist in removal of a wheel, a brake rotor, a brake drum, or the like, from a vehicle. These devices may generally be described as “wheel-pulling” apparatuses, even though they can also be used for removal of brake drums or brake rotors, in addition to the removal of wheels or wheel rims, from the vehicle.  
           [0007]    Some of these known prior art devices are described hereinbelow.  
         PRIOR ART  
         [0008]    In U.S. Pat. No. 3,402,455 (Converse), issued Apr. 17, 1967, a wheel puller device is described having a central threaded screw which pushes on the hub (or axle) of the vehicle wheel, while two spring-loaded hooks grasp and pull at the rear of the wheel or brake drum to be removed.  
           [0009]    In U.S. Pat. No. 3,689,978 (Kelso), issued Sep. 12, 1972, a similar wheel or gear puller device is shown having a central threaded screw which pushes on the hub of the vehicle wheel or gear. Two hooks are attached in the radial grooves of a central yoke or bridge so that the hooks can be moved to be essentially parallel to the central threaded screw during use.  
           [0010]    U.S. Pat. No. 4,771,528 (Stromberg), issued Sep. 20, 1988, describes a spindle puller for removal of the front wheel spindle on a four-wheel drive vehicle. Again, the described spindle puller has a central threaded screw which pushes on the axle, while a base plate acts to pull on the spindle. It should be noted that the user is warned not to hammer on the threaded screw, since internal axle parts may be damaged.  
           [0011]    U.S. Pat. No. 4,908,925 (Johnson), issued Mar. 20, 1990, describes a wheel hub puller which is used to remove the wheel hub from a axle housing. Again, a central threaded screw acts to push on the axle, while a support frame, bolted to the wheel hub using the wheel lugs (and bolts) acts to pull on the wheel hub.  
           [0012]    U.S. Pat. No. 6,012,211 (Ochoa et al.), issued Jan. 11, 2000, describes a wheel puller apparatus having a plate which rests upon the wheel mounting studs, and having two threaded hook portions which extend through the plate and hook onto the rear of the wheel. As bolts are tightened on the threaded hooks, the plate pushes against the wheel mounting studs, while the hooks pull on the wheel rim. The two hooks are alternatively “pulled” so that the pushing and pulling forces are first applied on one side of the wheel and then applied on the opposite side of the wheel. This results in a rocking motion which can result in damage to the wheel or brake assembly due to the side-to-side motion of the wheel as it is being freed.  
           [0013]    U.S. Pat. No. 6,237,206 (Bezemer et al.), issued May 29, 2001, describes a device for removal of a wheel from a wheel hub, having a threaded screw connected to a retainer through a base plate, which threaded screw is engaged with the wheel hub, and a series of chains with hooks for releasably attaching the base plate to the wheel. As the treaded screw is tightened, the retainer pushes on the retainer, while the chains act to pull on the wheel rim.  
           [0014]    While these devices have shown some utility in the field, they are primarily intended for use on trucks and heavy duty equipment in a garage environment, or they are intended for use with wheels that are hub-mounted, as opposed to being stud-mounted, on the vehicle.  
           [0015]    Accordingly, while these prior art devices have proven to be of some use, the continued mechanic&#39;s practice of hammering seized parts is evidence that a further improvement in wheel-pulling apparatuses would be beneficial.  
         SUMMARY OF THE INVENTION  
         [0016]    Accordingly, it is a principal object of the present invention to provide a simple wheel-pulling device which can be readily used on a wide variety of vehicle types for removal of wheels, brake rotors and/or brake drums.  
           [0017]    It is a further object of the present invention to provide a wheel-pulling device which acts to avoid exerting a pushing force directly on the axle or hub of the vehicle.  
           [0018]    It is still a further object of the present invention to provide a wheel-pulling device which acts while avoiding a damaging rocking, or side-to-side-motion.  
           [0019]    These and other objects are attained by providing a wheel-pulling device having a push plate which acts to push upon the mounting studs of a wheel, hook members to pull on the wheel, brake rotor or brake drum, a pull plate to which the hook members are attached, and a threaded pilot shaft which is threaded through the pull plate so that when tightened, the pilot shaft acts to push against the push plate (which in turn acts to push against the wheel studs), and pulls the hook members so as to pull the wheel rim.  
           [0020]    Accordingly, the present invention provides a wheel-pulling apparatus comprising:  
           [0021]    a. a push plate adapted to be placed in operative contact with a plurality of wheel studs;  
           [0022]    b. a pull plate having two or more hook attachment points;  
           [0023]    c. two or more hook members adapted to be attached, at a first end, to said pull plate at said hook attachment points, and which hook members are adapted to connect, at a hook end, to a wheel rim, a brake drum or a brake rotor; and  
           [0024]    d. a threaded pilot shaft which threads through a threaded opening in said pull plate, and abuts, at a proximate end, against said push plate, and which pilot shaft has, at a distal end, a turning mechanism for turning said threaded pilot shaft within the threaded opening in said pull plate, so that said push plate exerts a pushing force on said wheel studs, and said pull plate exerts a pulling force on said wheel rim, brake drum or brake rotor, through said hook members.  
           [0025]    Preferably, the wheel-pulling apparatus also provides a plurality of socket pins adapted to being attached to said plurality of wheel studs, wherein said socket pins are in contact with said push plate.  
           [0026]    In a second aspect, the present invention also provides a method for the removal of a brake drum a wheel, or a brake rotor using an apparatus of the present invention as herein described.  
         DETAILED DESCRIPTION OF THE INVENTION  
         [0027]    In the context of the present specification, the phrase “wheel studs” is intended to mean the bolt ends which typically extend from the wheel hub on which the wheel, brake rotor, brake drum, or the like, are mounted. The “wheel studs” normally remain on the vehicle after the wheel has been removed. However, the phrase is also meant to include a series of bolts which might be inserted into the wheel stud openings on the hub in the situation where the actual studs are removed when the wheel is removed. The number of wheel studs can vary from vehicle to vehicle, but typically, the number of wheel studs ranges from between 3 and 8, but more typically is between 4 and 6.  
           [0028]    In the practice of the present invention, it is preferred that the push plate exert a simultaneous pushing force against a plurality of wheel studs, and more preferably a simultaneous pushing force against all of the wheel studs (or socket pins, where used). The phrase “simultaneous pushing, force” is intended to mean that the push plate generally acts on more than one wheel stud, and preferably on all wheel studs (or socket pins), as the turning mechanism is turned.  
           [0029]    Preferably, the push plate has a central recess on one surface for receiving one end of the pilot shaft. Where the pilot shaft has a small diameter section at the end, the recess in the push plate may also be a hole through the push plate, provided that the diameter of the hole is less than the larger diameter section of the pilot shaft.  
           [0030]    The push plate also preferably comprises a number of holes or recesses on a second surface into which the wheel studs of the socket pins can be inserted. Again, where the socket pins have a small diameter section at the end, the recess in the push plate may be a suitably sized hole. The number of holes or recesses, and sizes of the holes or recess will preferably match, or be selected based on the number and size of the wheel studs or the socket pins.  
           [0031]    The recess in second surface of the push plate might also be a circular groove in which all of the wheel studs or socket pins will fit.  
           [0032]    The push plate is preferably circular in shape to agree with the shape of the wheel rim, brake drum or brake rotor, although a variety of shapes might be used. Preferably the push plate is of a size to cover all of the wheel studs, but should not be significantly larger to avoid interference with the hook members unless allowances are made for the hook members to avoid interference with the push plate.  
           [0033]    The term “hook members”, or “hooks” is used in a general sense to include devices which have a traditional hook-shaped design. However, the term can also cover a series of designs, including, for example, an L-shaped design which can be used for situations where the clearance distance between parts is relatively small. Further, the term hook may also be interpreted as a device which merely contains a small “shoulder” area which can be used to exert a pulling force on the wheel, the wheel drum or brake rotor.  
           [0034]    The hooks are preferably attached to the pull plate at a hook attachment point using one or more bolts at a threaded end of the hook. Preferably, between 3 and 8 hook members are used in the practice of the present invention, and more preferably, between 4 and 6 hook members are used.  
           [0035]    A pull plate may comprise a number of hook attachment points regardless of the number of hooks being used. The number, size and location of the hook attachment points will vary depending on the size of the hooks and the configuration of the wheel rim, brake drum or brake rotor. The hook attachment points might be threaded holes into which the threaded end of the hook could be tightened, or could simply be holes through which the threaded end of the hook could be passed and then held in place by an additional bolt.  
           [0036]    The pull plate can have a wide variety of shapes and sizes. For example, the pull plate might be circular in shape and be provided with a series of threaded holes into which the hook members might be threaded. However, in a preferred configuration, the pull plate comprises a small central portion having a threaded central hole for the pilot shaft to pass through, and a plurality of radial arms extending from the central portion, to which the hook members can be attached. The number of radial arms should preferably agree with the number of hooks to be used. Preferably the number of radial arms would be between 3 and 8 and more preferably, between 4 and 6.  
           [0037]    In a preferred embodiment, the pull plate will have a small central portion and a plurality of radial arms each having a slot into which the threaded end of the hook member can be inserted and adjusted before being tightened into place.  
           [0038]    The pilot shaft is of sufficient length to pass through the pull plate and abut against the push plate. The pilot shaft is threaded in the area of where it passes through the pull plate, and thus is threaded into the threaded hole in the centre of the cental portion of the pull plate.  
           [0039]    At one end, the pilot shaft preferably has a bolt shaped head onto which a wrench or a wrench-shaped crank can be attached, and thus provides a turning mechanism for turning the pilot shaft. Alternatively, the crank can be formed as part of the pilot shaft so that no additional crank or wrench, or the like, is required.  
           [0040]    All parts of the apparatus of the present invention are preferably made of materials which are able to withstand the forces exerted during operation. A suitable material would be, for example, steel, for most applications. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0041]    Various embodiments of the wheel pulling apparatus of the present invention will now be described by reference to the following drawings wherein:  
         [0042]    [0042]FIG. 1 is a perspective, exploded view of a wheel pulling apparatus according to the present invention;  
         [0043]    [0043]FIG. 2 is a side, cut-away view of a wheel pulling apparatus according to the present invention being used to remove a brake drum;  
         [0044]    [0044]FIG. 3 is a perspective view of an alternative design of a wheel pulling apparatus according to the present invention;  
         [0045]    [0045]FIG. 4 is a top plan view of the pull plate of the wheel pulling apparatus of FIG. 3;  
         [0046]    [0046]FIG. 5 is a side plan view of the pull plate of the wheel pulling apparatus of FIG. 3;  
         [0047]    [0047]FIG. 6 is a side plan view of a hook of the wheel pulling apparatus of FIG. 3;  
         [0048]    [0048]FIG. 7 is a side plan view of an alternative hook design;  
         [0049]    [0049]FIG. 8 is a side plane view of a further alternative hook design;  
         [0050]    [0050]FIG. 9 is a top plan view of the push plate of the wheel pulling apparatus of FIG. 1; and  
         [0051]    [0051]FIG. 10 is a cut-away side view of the socket pin of the wheel pulling apparatus of FIG. 1 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0052]    Other features of the present invention, as well as other objects and advantages attendant thereto, are set forth in the following description and the accompanying drawings in which like reference numerals depict like elements.  
         [0053]    In FIG. 1, a wheel pulling apparatus  10  in accordance with the present invention is shown having a pull plate  12 , which in this embodiment has a central portion  14  and five radial arms  16 . Each radial arm has a slot  18  through which, preferably 5 hooks  20  can be fed. Slots  18  allow hooks  20  to be positioned in a suitable position as described hereinbelow.  
         [0054]    Extending through the centre of cental portion  14  of pull plate  12  is a pilot shaft  22  which is threaded in at least the area in contact with pull plate  12 . Pull plate  12  is also treaded in this area to receive the threaded section of pilot shaft  22 . At one end, pilot shaft  22  has a bolt shaped end  24  which can be releasably attached to a wrench or to a crank  26 . Crank  26  can then be used to turn pilot shaft  22 .  
         [0055]    At the other end of pilot shaft  22  is a tapered, or smaller diameter end  28  which is adapted to fit into a recess  30  in push plate  32 . Push plate  32  also contains, in this embodiment,  5  holes  34  into which the tapered, or smaller diameter ends  38  of socket pins  36  can be fitted.  
         [0056]    [0056]FIG. 2 shows the use of the device of FIG. 1 to remove a brake drum  50  from a wheel hub  42 . In use, the operator would insert socket pins  36  over the wheel studs  40  which extend from wheel hub  42 . Socket pins  36  can be threaded onto wheel studs  40 , but might also have a sufficiently large opening to allow socket pins  36  to be merely inserted over wheel studs  40 . Use of the socket pins  36  can be eliminated, but is generally preferred in order to minimize any damage to wheel studs  40 .  
         [0057]    For the purposes of the present document, the wheel hub  42  is generally defined as the area of the vehicle wheel in the general area of the vehicle axle. In the practice of the present invention, the force exerted on the wheel axle and/or hub is reduced since the push plate exerts a simultaneous force on the wheel studs. As such, the force exerted on the wheel hub is minimized, or at least evenly spread over the entire wheel hub.  
         [0058]    Once socket pins  36  are in place, push plate  32  is attached so that the tapered ends of socket pins  36  extend through push plate holes  34 . Preferably the fit of pins  36  in push plate  32  is sufficiently tight to hold pins  36  and push plate  34  together with the larger section of pins  36  being in contact with push plate  32 . Holes  34  do not need to extend through push plate  32 , but might merely be recesses in push plate  32 .  
         [0059]    One end of pilot shaft  22  is inserted into the recess  30  in push plate  32 . The “hooked” end of hooks  20  are then brought into contact with the back edge  52  of brake drum  50 . Details of the braking system are outside of the scope of this invention, and are not shown in the figures. The other ends of hooks  20  are fed through slots  18  in radial arms  16  of pull plate  12 . The hooks can then be bolted into place using bolts  54  and  56 . The hooks are preferably placed on radial arms  16  so that the shaft area  21  of hooks  20  is essentially perpendicular to the front surface  51  of brake drum  50  (or said brake rotor or wheel rim, as applicable).  
         [0060]    Once all of the hooks  20  are in place, the end of crank  26  is fitted over the bolt-shaped end  24  of pilot shaft  22 . The crank  26  is then turned.  
         [0061]    As the crank  26  is turned, pilot shaft  22  attempts to move through pull plate  12 . As a result of this motion, a pushing force is exerted onto push plate  32 , which in turn, acts to exert a pushing force onto wheel studs  40  through socket pins  36 . At the same time, a pulling force is exerted onto pull plate  12  which acts to exert a pulling force onto brake drum  50  through hooks  20  which are attached to the radial arms  16  of pull plate  12 .  
         [0062]    The combination of pushing force on the wheel studs, and the pulling force on the brake drum, act to free the seized brake drum from the wheel hub. It should be noted, that generally only a very small movement of brake drum  50  is required using the device of the present invention, since once the brake drum has been freed from the wheel hub, it can then be removed by hand.  
         [0063]    In FIG. 3, a alternative design  10 A for a wheel pulling apparatus of the present invention is shown having many of the same parts as in the wheel pulling apparatus of FIG. 1. However, in this embodiment, only 4 radial arms  16 A are used, and arms  16 A are bent so as to reduce the length of hooks  20 A.  
         [0064]    Also, in this design, the holes (not shown) in push plate  32 A are merely recesses in push plate  32 A and do not extend through push plate  32 A. It should also be noted, however, that socket pins  36  may be permanently attached to push plate  32 A if the device is commonly used for one standard wheel stud configuration.  
         [0065]    Also, in this embodiment, it should be noted that the slots  18  in radial arms  16 A have been eliminated in favour of pre-set holes  18 A in radial arm  16 A. Again, this might be preferred in situations where a standard wheel configuration is commonly used.  
         [0066]    A top plane view of the pull plate  12 A of the device of FIG. 3 is shown in FIG. 4. It can be seen that the central portion of  14 A of pull plate  12 A is generally quite small and merely includes a small plate around a threaded, central hole  11  through which pilot shaft  22  is inserted.  
         [0067]    It should be noted, however, that numerous designs can be used in the production of pull plate  12 , including a solid circular plate which contains holes for hooks  20  in appropriate locations, slots for hooks  20 , or the like. The key requirements for the pull plate, however, are that the pull plate have holes, preferably at or near the centre of the plate, through which the pilot shaft can be threaded, and hook attachment points where a plurality of hooks can be permanently or releasably attached.  
         [0068]    In FIG. 5, a side plane view of the pull plate of FIG. 4 is shown, which provides more detail on the construction of the wheel pulling apparatus.  
         [0069]    In FIG. 6, a side plane view of a hook  20  of use in the present invention is shown. Hook  20  has a shaft section  21 , and preferably a threaded section  23  at one end of the shaft section  21  in order that the hook  20  can be bolted to radial arms  16 . The “hook” section  25 , may merely be a circular metal piece bent to 90 degrees from shaft section  21 .  
         [0070]    In FIG. 7, an alternative design for hook  20  is shown, and is designated as  20 A. For removal of some types of brake rotors, the hook shown in FIG. 5 would be acceptable. In some brake disk designs, both the front and back surfaces of the rotor are smooth for the brake pad to act against. Further, in order to aid in cooling of the rotor, some are built with open areas extending from the outer perimeter of the rotor into the rotor, between the rotor front and back surfaces. The hook  20 A of FIG. 7 has a shaft section  21  and treaded section  23  identical to the hook of FIG. 5. However, the hook section  25 A, is flattened along its surface to facilitate insertion of the “hook” into the brake rotor.  
         [0071]    Hooks  20 A of this design may be used in this application, as well as a variety of other applications.  
         [0072]    In FIG. 8, a further side plan view of an additional hook design, designated as  20 B, is shown. In this design, hook section  25 B is merely the “shoulder” of shaft section  21 . This hook design would be of use in removal of a brake drum, having a relatively thin casing.  
         [0073]    In FIG. 9, a top plan view of the push plate  32  of FIG. 1 is shown. Push plate  32  has  5  holes  34  equally spaced around the push plate. Each hole  34  is located at an equal distance from the centre of the push plate  32 , as indicated by line  35 , and are placed so as to correspond to the spacing of the vehicle wheel studs. Holes  34  are adapted to receive the socket pins  36 , as hereinabove described. Recess  30  in the top surface of push plate  32  is preferably centred in the middle of push plate  32 , and is adapted to receive the end of pilot shaft  22 .  
         [0074]    [0074]FIG. 10 shows a cut-away view of a socket pin  36  of use in the practice of the present invention. Socket pins  36 , in the embodiment shown in FIG. 1, comprise 2 main sections, namely, a tapered, smaller diameter section  60 , for insertion into push plate  32 , and a larger diameter section  62  for fitting over the end of the wheel studs. Socket pin  36  in this embodiment is threaded on the internal section  64  of larger diameter section  62  so that the socket pin  36  can by threaded onto the wheel stud.  
         [0075]    Thus, it is apparent that there has been provided, in accordance with the present invention, a wheel pulling apparatus which fully satisfies the means, objects, and advantages set forth hereinbefore. Therefore, having described specific embodiments of the present invention, it will be understood that alternatives, modifications and variations thereof may be suggested to those skilled in the art, and that it is intended that the present specification embrace all such alternatives, modifications and variations as fall within the scope of the appended claims.  
         [0076]    Additionally, for clarity and unless otherwise stated, the word “comprise” and variations of the word such as “comprising” and “comprises”, when used in the description and claims of the present specification, is not intended to exclude other additives, components, integers or steps.