Abstract:
A mounting assistance device with which a vibrating device can be efficiently mounted to a tire and wheel assembly. In the mounting assistance device, abutting portions are made to abut against sidewall portions of a tire and then an eccentric disc is pressed against a sliding portion so as to be united therewith by lowering a lever of a handle member in a first direction. In this state, when the lever is rotated 180° about a pin member in a second direction, due to an effect of the eccentric disc, clamping members move in a mutually approaching direction. Accordingly, clamping and fixing to the tire is accomplished by the mounting assistance device. Thus, the mounting assistance device (and vibrating device) can be mounted without using tools, simply by rotating the lever in the two directions.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a mounting assistance device of a tire and wheel assembly, and more particularly, to a mounting assistance device of a tire and wheel assembly to accurately align a center of rotation of the assembly with an axle of an automobile when mounting the tire and wheel assembly onto the axle of the automobile. 
     2. Description of the Related Art 
     In an operation for mounting the tire and wheel assembly (which may be referred to simply as an assembly hereinafter) to the axle of a vehicle, it is vital to make the center of rotation of the tire and wheel assembly coincide with a central axis of the axle of the vehicle. 
     However, in this mounting operation, a moment, which tends to move a center of gravity of the assembly downwards from a center of rotation of the axle of the vehicle, always acts because of factors such as the assembly being heavy, the center of gravity of the assembly being offset toward an outside of the vehicle, and the like. As a result, the axle of the vehicle may not coincide with the center of rotation of the assembly and the assembly may end up being mounted to the axle of the vehicle in an eccentric state. 
     If the vehicle is run with the center of gravity of the assembly being eccentric as described above, because vibrating forces act on the vehicle from unsprung parts, vibration is generated and the tire is unevenly worn. 
     As a mounting method for avoiding the above-described drawbacks, there has been conventionally used a method in which the assembly is rotated while the tire thereof is tapped, diagonal pairs of one of mounting nuts and wheel bolts are successively tightened little by little until the one of nuts and bolts are not loose, and then final tightening thereof is carried out with a torque wrench. 
     However, this method depends to a large extent on levels of skill of operators and is not generic. 
     The present applicant has suggested a mounting assistance device, with which variations between operators are suppressed and an assembly is mounted to the axle of the vehicle with high accuracy without the assembly being caused to be eccentric, and a method thereof (Japanese Patent Application Laid-Open (JP-A) No. 7-228102). As illustrated in FIG. 8, in a mounting assistance device  2 , clamping members  8  and  10  abut against both side surfaces (sidewall portions) of a tire  6  of an assembly  4 , and a nut  11  is tightened. As a result, an eccentric disc  12  cannot move in directions X with respect to the clamping member  10 . When a handle  14  is rotated, the clamping member  8  and the clamping member  10  are caused to approach each other by a cam action of the eccentric disc  12  thereby clamping the tire  6 . In this state, rotation of the eccentric disc  12  is disabled by a nut  16 . Accordingly, a tightened state is locked so that a fixed state is securely maintained. 
     Vibration is applied to the assembly  4  in the above-described state by a vibrating device  18 . Vibration of the assembly  4  acts to offset eccentricity of the center of rotation of the assembly  4 . Accordingly, even if an operator is not skilled, the operator can mount the assembly to the axle of the vehicle with high accuracy by further tightening the one of hub bolts and nuts while vibrating the assembly. 
     However, when the mounting assistance device  2  is mounted to the assembly  4 , it is necessary to use a tool to tighten the nuts  11  and  16  to fix the eccentric disc  12  to the clamping member  10  and to maintain the tightened state, which is complicated. Accordingly, it has been desired that the mounting operation of the mounting assistance device  2  (the vibrating device  18 ) should be carried out more efficiently. 
     SUMMARY OF THE INVENTION 
     The present invention is provided to solve the above-described problems and an object of the present invention is to provide a mounting assistance device which can efficiently mount a vibrating device to a tire and wheel assembly. 
     In order to accomplish the object, in a first aspect of the present invention, a mounting assistance device which clamps a tire-and-wheel assembly from both side surfaces thereof and vibrates the assembly comprises a first clamping member and a second clamping member for clamping the both side surfaces of the assembly; a first abutting portion and a second abutting portion which are portions of the first clamping member and the second clamping member respectively, and which abut against the side surfaces of the assembly, and which face each other with a distance therebetween which can be adjusted; a vibrating device which is fixed to one of the first clamping member and the second clamping member; a first eccentric member which is rotatably disposed at the second clamping member so as to abut against the first clamping member and is urged onto the second clamping member such that the first eccentric member moves integrally with the second clamping member; a first lock mechanism for fixing the first eccentric member to the second clamping member; and a handle member which enables an operation for fixing the first eccentric member to the second clamping member via the first lock mechanism, and enables an operation for rotating the first eccentric member; wherein the distance between the first abutting portion and the second abutting portion can be adjusted by rotation of the first eccentric member. 
     The mounting assistance device having the above-described aspect is used for mounting the assembly to an axle of a vehicle. 
     Firstly, the assembly is temporarily mounted to the axle of the vehicle with one of mounting nuts and wheel bolts. A distance between the first abutting portion of the first clamping member of the mounting assistance device and the second abutting portion of the second clamping member of the mounting assistance device is adjusted such that the first and the second abutting portions abut against sidewall portions of a tire. In this state, when the handle member is operated, the first eccentric member, which abuts against the first clamping member, is fixed to the second clamping member by the first lock mechanism. 
     Then, due to rotation of the first eccentric member, which is fixed at the second clamping member, by the operation of the handle, the distance between the first abutting portion and the second abutting portion is further contracted by an action of the first eccentric member which is, for example, an eccentric cam. 
     In this way, the mounting assistance device is tightened and fixed to the tire of the assembly and, even when vibration is applied to the assembly by the vibrating device, the mounting assistance device does not detach from the assembly. Thereafter, by gradual tightening of the one of mounting nuts and wheel bolts while the assembly is being vibrated, the wheel is mounted to the axle of the vehicle without the center of rotation of the wheel becoming eccentric with respect to the axle of the vehicle. 
     In accordance with the mounting assistance device based on the above-described aspect, the mounting assistance device can easily be mounted to the assembly simply by operation of the handle, without using a tool or the like. Accordingly, operating efficiency of a mounting operation is enhanced. 
     In a second aspect of the present invention, the first lock mechanism is formed as a second eccentric member, and by operation of the handle member in a first direction, the second eccentric member is rotated such that the first eccentric member and the second eccentric member are made integral and, by operation of the handle member in a second direction which is different from the first direction, the first eccentric member is rotated together with the second eccentric member. 
     According to the second aspect, since the handle member is provided with the second eccentric member, an operator can fix the first eccentric member to the second eccentric member (make the first eccentric member integral with the second eccentric member) and rotate the first eccentric member with the second eccentric member so as to reduce the distance between the first abutting portion and the second abutting portion, simply by operating the handle member in the first direction and the second direction. Accordingly, the operating efficiency of the mounting operation is further enhanced. 
     In a third aspect of the present invention, the mounting assistance device of the present invention further comprises a second lock mechanism to fix the first abutting portion and the second abutting portion such that a distance therebetween is constant. 
     In accordance with the third aspect, the mounting assistance device is fixed on the assembly by clamping the assembly with the first and second clamping members. Then, the clamped state (the distance between the first and the second abutting portions) is fixed by the second lock mechanism. Accordingly, the clamped state can be reliably maintained even when the vibrating device is driven. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a mounting assistance device in accordance with one embodiment of the present invention. 
     FIG. 2 is an exploded perspective view of the mounting assistance device in accordance with one embodiment of the present invention. 
     FIG. 3 is a cross-sectional view of the mounting assistance device in accordance with one embodiment of the present invention showing a state in which an eccentric portion and an eccentric plate are unlocked. 
     FIG. 4 is a plan view of the mounting assistance device in accordance with one embodiment of the present invention illustrating a state in which the eccentric portion and the eccentric plate are locked. 
     FIG. 5 is a cross-sectional view of the mounting assistance device in accordance with one embodiment of the present invention illustrating a state in which the eccentric portion and the eccentric plate are locked. 
     FIG. 6 is a plan view of the mounting assistance device in accordance with one embodiment of the present invention illustrating a state in which a distance between abutting portions has contracted so as to clamp a tire. 
     FIG. 7 is a cross-sectional view of the mounting assistance device in accordance with one embodiment of the present invention illustrating a state in which a distance between abutting portions has contracted so as to clamp a tire. 
     FIG. 8 is a side view of a conventional mounting assistance device. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A mounting assistance device relating to one embodiment of the present invention will be described. 
     A mounting assistance device  20  has, as illustrated in FIGS. 1 and 2, a pair of clamping members  22  and  24 . The clamping member  22  is formed in a substantially L-shaped configuration by a sliding portion  22 A and an abutting portion  22 B, which is formed continuously with and at a right angle to the sliding portion  22 A. A protective member  22 C for protecting a tire at a time of abutting against the tire is fixed at an inner side of the abutting portion  22 B. The clamping member  24  is the same in these respects as the clamping member  22 . 
     A pair of guide plates  26 , a mounting plate  28 , and an angle member  32  at which a vibrating device  30  is fixed are integrally fixed to the clamping member  22  by screws  34 . 
     As a result, the sliding portion  24 A of the clamping member  24  slides within a clearance portion  36  (see FIG.  4 ), which is formed by the clamping member  22  (sliding portion  22 A), the guide plates  26 , and the mounting plate  28 , so as to adjust a distance between the abutting portions  22 B and  24 B. 
     An elongate hole  38  which extends along a sliding direction is formed at a sliding direction (a direction of arrow X 1 ) end portion of the sliding portion  24 A of the clamping member  24 . 
     A pin member  40  passes through the elongate hole  38 . The pin member  40  passes through, above the sliding portion  24 A, a thrust bearing  42  and a center of rotation of an eccentric disc  46  which is rotatably supported by the thrust bearing  42  (the center of rotation of the eccentric disc  46  is offset from a center of the disc). Because of the above-described structure, the eccentric disc  46  can be eccentrically rotated about the pin member  40  at the sliding portion  24 A in directions of arrows P. 
     A handle member  48  is disposed at an upper portion of the eccentric disc  46 . The handle member  48  is formed by an eccentric portion  50 , which is a substantial cylinder with a portion of an outer circumferential surface thereof cut away, and a lever  52  which is fixed at the outer circumferential surface of the eccentric portion  50 . A ring-shaped engaging portion  54  formed at a head portion of the pin member  40  is inserted into a cutout portion  53  formed at a central portion of the eccentric portion  50 . A pin  56 , which passes through a center of rotation of the eccentric portion  50 , passes through the engaging portion  54 . Accordingly, as illustrated in FIG. 3, the eccentric portion  50  can rotate about the pin  56  in directions of arrows Q. 
     That is, the handle member  48  rotates about the pin member  40  in directions of arrows P, thereby rotating the eccentric disc  46  (see FIG.  4 ). The handle member  48  also rotates about the pin  56  in the directions of arrows Q, thereby rotating the eccentric portion  50  (see FIG.  3 ). 
     Under the sliding portion  24 A, the pin member  40  passes through a thrust bearing  58 , an engaging member  62  for an urging mechanism  60  which is described below, and a spring  64 . A nut  68  is screwed onto a thread portion  66  which is formed at a distal end portion of the pin member  40 . 
     The urging mechanism  60  is formed by a ring-shaped engaging portion  70  which forms the engaging member  62 , a shaft portion  72  which is formed protruding from an outer circumferential surface of the engaging portion  70 , a brace member  74  which is fixed at the abutting portion  22 B and through which a distal end of the shaft portion  72  is inserted, and a spring  76  which is wound around the shaft portion  72  between the brace member  74  and the engaging portion  70 . Accordingly, the spring  76  always presses the engaging portion  70  (the pin member  40 ) in the direction of arrow X 2 . 
     A shaft  82  of a lock member  80  is screwed into the angle member  32 . A distal end of the shaft  82  can be pressed against the sliding portion  24 A through a penetrating hole formed in the mounting plate  28 , by rotation of a lever  84 , such that the sliding portions  22 A and  24 A are prevented from sliding relative to each other. That is, the distance between the abutting portions  22 B and  24 B can be kept constant. 
     A method of mounting an assembly  90  to an axle of a vehicle using the mounting assistance device  20  which is structured as described above will be described hereinafter. 
     Firstly, a tire  92  is inflated to a predetermined internal pressure value. Then, with an appropriate balancer, the imbalance value of the assembly  90  is set zero or a value close to zero. The assembly  90  is then mounted with a suitable looseness with respect to a hub of the axle of the vehicle. 
     At this time, the lever  52  of the handle member  48  stands in a direction substantially perpendicular to the sliding portion  24 A, as shown in FIG. 3, and a round outer circumferential surface  50 A of the eccentric portion  50  abuts against the eccentric disc  46 . Further, of the outer circumferential surface of the eccentric plate  46 , a portion that is closest to the center of rotation of the eccentric plate  46  (at a distance L 1  therefrom) abuts against an end portion of the mounting plate  28 . 
     Then, the mounting assistance device  20 , in which the distance between the abutting portions  22 B and  24 B has been widened so as to exceed a maximum width of the tire  92 , is fitted onto the assembly  90  from thereabove (a tread side of the tire  92 ). One or both of the sliding portions  22 A and  24 A of the clamping members  22  and  24  are slid, thereby causing the protective members  22 C and  24 C of the abutting portions  22 B and  24 B to abut against sidewalls of the tire  92 . 
     Because the brace member  74  moves in the direction of arrow X 2  together with the clamping member  22  (the abutting portion  22 B), the spring  76  of the urging mechanism  60  is compressed and the pin member  40  (the eccentric disc  46 ) is pressed in the direction of arrow X 2  by the elastic force of the spring  76 . Accordingly, the mounting plate  28  also moves in the direction of arrow X 2  together with the clamping member  22 . The eccentric disc  46  follows the mounting plate  28  in the direction of arrow X 2  and the abutting state of the eccentric disc  46  against the mounting plate  28  is maintained. 
     In this state, when the lever  52  is rotated about the pin  56  in the direction of arrow Q 1 , a flat surface portion  50 B of the eccentric portion  50  abuts against the eccentric disc  46  (see FIG.  3  and FIG.  5 ). As a result, a distance from an upper surface of the eccentric disc  46  to the pin  56  is increased (from a distance D 1  in FIG. 3 to a distance D 2  in FIG. 5 because the eccentric portion  50  is structured such that D 2  &gt;D 1 ). 
     At this point, because a distance from the pin  56  to the nut  68  is constant, the thrust bearing  42  presses against the sliding portion  24 A. As a result, the pin member  40  can no longer move along the elongate hole  38  (the pin member  40  is fixed with respect to the sliding portion  24 A). However, because the load applied on the eccentric disc  46  is supported by the thrust bearing  42 , the eccentric disc  46  is rotatable. 
     In this state, the flat surface portion  50 B of the eccentric portion  50  presses against the eccentric disc  46 . Thus, the eccentric portion  50  moves integrally with the eccentric disc  46 . 
     Then, the lever  52  is rotated substantially 180° about the pin member  40  in the direction of arrow P 1  (see FIGS. 4 and 5, and FIGS.  6  and  7 ). Of the outer circumferential surface of the eccentric disc  46 , a portion that is farthest to the center of rotation of the eccentric disc  46  (at a distance L 2  therefrom) abuts against the mounting plate  28 . As a result, the clamping member  22  is moved at a distance of (L 2 -L 1 ) in the direction of arrow X 2  relative to the clamping member  24 . Accordingly, the distance between the abutting portions  22 B and  24 B is reduced such that the tire  92  can be tightly clamped. Further, when the lever  84  of the lock member  80  is rotated, the distal end of the shaft  82  presses the mounting plate  28  such that the sliding portion  22 A and the sliding portion  24 A are fixed to each other. 
     In the present embodiment, the lever  52  is rotated substantially 180° about the pin member  40  in the direction of arrow P 1 . However, it should be understood that the degree of rotation of the lever  52  is not necessarily limited to 180°. As long as the clamping member  22  is moved at a sufficient distance in the direction of X 2  relative to the clamping member  24 , the shape of eccentric disc  46  and the degree of rotation of the lever  52  required for an effective rotation of the eccentric disc  46  may be changed as desired. 
     In this way, the mounting assistance device  20  is fixed to the assembly  90 . Then, the vibrating device  30  is driven to vibrate the assembly  90 . While the assembly  90  is vibrating, a plurality of mounting nuts are successively tightened up little by little (in any order). When the mounting nuts have been tightened up, the center of rotation of the assembly  90  is accurately aligned in a straight line with an axial center of the vehicle. 
     When the mounting assistance device  20  is removed from the assembly  90 , the following operations are carried out: the lever  84  of the lock member  80  is rotated to an unlocked state; the lever  52  is rotated about the pin member  40  in the direction of arrow P 2  so as to turn the eccentric disc  46  back; the lever  52  is rotated about the pin  56  in the direction of arrow Q 2  to be raised, and thus locking of the eccentric disc  46  with respect to the sliding portion  24 A is released; and the abutting portions  22 B and  24 B are moved away from each other so as to be spaced from the sidewall portions of the tire  92 . Then, the mounting assistance device  20  can be removed from the tire  92 . 
     Hence, for mounting the mounting assistance device  20  of the present embodiment to the assembly  90 , simple operation of the handle member  48  suffices and there are no operations for which a tool is needed, such as tightening of nuts. Accordingly, mounting operation efficiency is enhanced. The handle member  48  is uniquely rotatable in two directions of rotation. Thus, fixing of the eccentric disc  46  with respect to the sliding portion  24 A and rotation of the eccentric disc  46  can be carried out by operation of the single handle member  48 . 
     Further, the mounting plate  28  is pressed against the sliding portion  24 A simply by rotation of the lever  84  of the lock member  80  and clamping of the abutting portions  22 B and  24 B with respect to the assembly  90  can be reliably maintained. 
     In the present embodiment, the handle member  48  and the lock member  80  are provided in lever form. However, these members can have any form that is easily operated such that cumbersome operations using tools are not required.