JP2000238995A - Car body support device for lift for automobile maintenance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply to a large range from an automobile lower in lifting point to an automobile higher in it, and adjust height of a receiving table at a short time by a simple operation. SOLUTION: A lift for automobile maintenance is provided with an arm 3 slidably in the axle direction. A receiving table 4 is liftably and horizontally supported on the tip of the arm 3 via parallel crank mechanisms 5. An involute cam 6 is rotatably supported by upside cranks 14 of the parallel crank mechanisms 5, a cam engaging member 20 is provided for downside cranks 15, interval between cranks 14, 15 is changed by the cam 6, and height of the receiving table 4 is adjusted. An extending portion of a cam shaft 19 is provided with a twisted spring 23 for energizing the cam 6 to the large-diameter portion side, and a knob 24 for rotating the cam 6 to the small-diameter portion side against this energizing force of the spring 23. A contact surface between the cam 6 and the engaging member 20 may be provided with a nonslip tooth.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supporting a vehicle body in an automobile maintenance lift.

[0002]

2. Description of the Related Art In general, in a lift for car maintenance, the car is lifted by supporting four lifting points of a vehicle body with pedestals. These lifting points are places where jacks are applied when changing tires, and for example, in the case of a monocoque body such as a passenger car, FIG.
Is designated at the position indicated by P. Since the height to the lifting point differs depending on the type of vehicle, it is necessary to adjust the height of the cradle.

Therefore, conventionally, a vehicle body supporting device using screws has been proposed. In the apparatus shown in FIG. 10, a female screw 53 is formed on the arm 52 of the elevating table 51, a male screw 54 is screwed onto the female screw 53, and the male screw 54 is rotated to adjust the height of the receiving table 55. . The device shown in FIG. 11 has a male screw 54 supported on an arm 52 via an intermediate screw 56. By rotating both screws 54, 56, a large height adjustment margin can be secured. The device shown in FIG.
The male screw 54 is supported through the nut 7, and the height of the receiving table 55 can be adjusted by rotating the nut 57. The apparatus shown in FIG.
The adjustment cost is large and the height can be adjusted.

[0004]

However, according to the conventional apparatus shown in FIGS. 10 and 12, the allowance for adjusting the height of the pedestal 55 is defined by the length of the male screw 54.
When the length of the male screw 54 is short, it becomes difficult to apply the method to a vehicle having a high lifting point. In the case of the apparatus shown in FIGS. 11 and 13, the use of the intermediate screw 56 increases the adjustment allowance.
In order to set 5 near the highest or lowest position, it was necessary to turn both the male screw 54 and the intermediate screw 56.

Further, if rust or foreign matter adheres to the screws during use for many years, the male screw 54, the intermediate screw 56, the nut 5
7 took a long time to set and reset the pedestal 55 because the rotation of 7 became heavy. In the case of the device shown in FIGS. 12 and 13, when fitting the groove of the receiving base 55 to the pinch panel of the vehicle body, while supporting the receiving base 55 so as not to rotate, the nut 57 is supported.
Had to be turned and forced to do both hands.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a vehicle maintenance device which can be applied to a wide range of vehicles from a vehicle having a low lifting point to a vehicle having a high lifting point and can adjust the height of a cradle in a short time by a simple operation. Is to provide.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a vehicle body supporting apparatus according to the present invention is an apparatus for supporting a vehicle body in an automobile maintenance lift. The cradle includes a receiving table, a parallel crank mechanism that supports the receiving table so as to be able to move up and down with respect to the arm in a horizontal posture, and a cam that adjusts the height of the receiving table.

Here, it is possible to provide the cam at a position directly engaging with the receiving table, but more preferably, the cam is rotatably supported on one of the cranks of the parallel crank mechanism.
It is preferable to provide a member that engages with the cam on the other crank (claim 2). In this case, since the cam acts to change the interval between the cranks, the parallel crank mechanism can be largely deformed at a small rotation angle of the cam, and the receiving table can be quickly arranged at the required height position. In this case, it is preferable to provide non-slip teeth on both or one of the contact surfaces of the cam and the engaging member so that the receiving table 4 can be firmly held (claim 3).

Further, the vehicle body supporting device of the present invention includes a spring member for urging the cam toward the large diameter portion. With this configuration, when the cradle is lifted, the cam rotates by the urging force of the spring member and automatically locks the parallel crank mechanism, so that the cradle can be set to the vehicle body by one-touch operation, and The height can be reliably maintained.

In this case, when the cam is rotated toward the small diameter portion at the time of resetting the cradle, the parallel crank mechanism falls down by its own weight, and the cradle quickly descends. At this time, it is preferable to provide an operation member that rotates the cam toward the small diameter portion against the urging force of the spring member so that the cam can be safely operated from the outside (claim 5).

Although a polygonal cam can be used as the cam, a curved cam is desirable in order to continuously adjust the height of the receiving table. Further, an involute cam in which the lift amount changes continuously is desirable in that the height of the cradle can be largely adjusted with a small rotation angle of the cam.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show one body support device. In a single-post type, two-post type or X-link type vehicle maintenance lift, the body support device is provided at four positions on the lift 1. And the vehicle body is supported by four lifting points (see FIG. 9). The vehicle body support device of this embodiment includes an arm 3 slidably provided on an elevating platform 1 in the axle direction, a receiving table 4 for receiving a pinch panel 2 of a vehicle body at a tip end of the arm 3, and It comprises a parallel crank mechanism 5 that supports the arm 3 so that it can move up and down with respect to the arm 3, and a cam 6 that adjusts the height of the cradle 4.

The receiving table 4 includes a base 8, a seat plate 9, and a rubber pad 1.
0. The rubber pad 10 is fixed to a seat plate 9, and the seat plate 9 is rotatably supported on a base 8 by a shaft 11 in a horizontal plane. A groove 12 is formed on the upper surface of the rubber pad 10, and the pedestal 4 supports the vehicle body with the groove 12 fitted in the pinch panel 2.

The parallel crank mechanism 5 has a pair of upper cranks 14 and a pair of lower cranks 15. The base end of each of the cranks 14 and 15 is connected to the arm 3 by a pin 16, and the free end is connected to the base 8 by a pin 17. 4
The two pins 16 and 17 form a parallelogram, keep the arm 3 and the cradle 4 in a parallel relationship at all times, and hold the cradle 4 in a horizontal posture with the swing of the cranks 14 and 15 in the horizontal state of the arm 3. To move up and down.

As the cam 6, an involute cam whose lift amount changes continuously is used. The involute cam 6 is rotatably supported by an intermediate portion of the upper crank 14 by a cam shaft 19, and a member 20 that engages with the involute cam 6 is fixed to the lower crank 15.
Then, as shown in FIGS. 4A to 4C, the involute cam 6 is rotated in a range of approximately 270 ° from the minimum diameter portion to the maximum diameter portion, and according to the cam profile in this range,
By changing the interval between the upper crank 14 and the lower crank 15, the height of the cradle 4 can be adjusted steplessly.

As shown in FIG. 1, the camshaft 19 is extended outside the upper crank 14, and a torsion spring 23 as a spring member for urging the involute cam 6 in the counterclockwise direction in the figure is provided at the extension. ing. Further, a knob 24 as an operation member for rotating the involute cam 6 is attached to the protruding end of the extension. At the time of setting, the involute cam 6 is rotated toward the large-diameter portion by the urging force of the torsion spring 23 with the rise of the cradle 4, and locks the parallel crank mechanism 5 via the engaging member 20. The rotation of the involute cam 6 toward the small-diameter portion side against the urging force of the torsion spring 23 allows the cradle 4 to descend.

In using the vehicle body supporting device having the above-described structure, first, as shown in FIG. 4A, with the receiving stand 4 being arranged at the lowest position, the receiving stand 4 is moved to four lifting points of the vehicle body. Align. In this case, since the minimum diameter portion of the involute cam 6 engages with the engagement member 20, the parallel crank mechanism 5 falls down flat, and the cradle 4 is arranged near the floor, the vehicle having a low lifting point is used. However, it is not hindered by the cradle 4.

Next, as shown in FIG. 4B, the receiving table 4 is lifted up by hand or the knob 24 is turned up, and the rubber pad 10 is turned to fit the groove 12 into the pinch panel 2 of the vehicle body. . At this time, the involute cam 6 is rotated toward the large-diameter portion by the urging force of the torsion spring 23 to rotate the parallel crank mechanism 5.
Is automatically locked, and even if an operator releases his / her hand from the cradle 4, the cradle 4 holds its height by itself. Further, as shown in FIG. 4 (c), if the cradle 4 is arranged at the highest position and held at the maximum diameter portion of the involute cam 6, even if the vehicle has a high lifting point, the rubber pad 10
Can be applied.

Thereafter, the remaining three vehicle body supporting devices are operated in the same manner, and four receiving stands 4 support four portions of the vehicle body. In this way, the setting operation can be completed in a short time by a simple operation of merely lifting the cradle 4. Further, since the height of each cradle 4 can be adjusted steplessly by the profile of the involute cam 6, even when the heights of the four lifting points are different, all the rubber pads 10 are correctly applied to the vehicle body, and the vehicle weight is reduced. Four cradle 4
And the vehicle can be lifted up in a stable state.

After the maintenance work is completed, the vehicle is lifted down by lowering the elevator 1 and the load is removed from the cradle 4, and the knob 24 is turned so that the involute cam 6 resists the urging force of the torsion spring 23. Then, it turns to the minimum diameter side.
Then, the parallel crank mechanism 5 falls down by its own weight of the cradle 4, and the cradle 4 quickly descends to the lowest position. Therefore, the cradle 4 can be reset from the vehicle body in a short time with a simple operation of simply turning the knob 24. The knob 24 is connected to the camshaft 19.
, The involute cam 6 can be safely operated from the outside.

Here, the self-locking action of the involute cam 6 will be described. The involute cam 6 is self-supported at the low, middle, and high positions of the cradle 4 at the positions shown in FIGS. 5A, 5B, and 5C, respectively.
In FIG. 5, O is the center of the cam shaft 19, B is the contact point between the involute cam 6 and the engaging member 20, and A is the engaging member 20.
, The contact point between the vertical line at the point B and the base circle of the involute cam 6, O → B is the load acting line, B → A is the reaction force direction line from the point B, and A → O is the base circle radius of the involute cam 6. And a line parallel to the engaging member 20.

Now, when a force in the O → B direction acts on the involute cam 6, a clockwise torque is generated in the figure. The tangential force at point B due to this torque is F
Then, since F = OBsin θ θ0>θ1> θ2 F0>F1> F2, F increases as the cradle 4 is lower.

At point B, a friction force P in the direction opposite to F is generated. Assuming that the friction coefficient is μ and the friction angle is K, P = μBA K = tan−1 μ.

The contact area at the point B is theoretically zero for the contact between the plane and the curved surface, but actually shows a certain finite value due to the elastic deformation of the metal material. However, since the value is very small, the point B is an extreme pressure contact with a very large surface pressure. The μ of the extreme pressure contact is about three times the μ of the normal contact, and is even larger when the surface roughness of the contact surface is low. Therefore, θ <K
If the cam shape is designed so as to satisfy the above condition, the receiving table 4 can be reliably held at an arbitrary height by not only the involute cam 6 but also a curved cam having another shape.

FIGS. 6 to 8 show modifications of the cam mechanism. In the cam mechanism shown in FIGS. 6 and 7, a large number of non-slip teeth 6 a,
20 a is formed parallel to the cam shaft 19. In this case, the receiving table 4 can be more firmly held by the engagement between the non-slip teeth 6a and the non-slip teeth 20a. In this case, the height adjustment of the pedestal 4 is stepped, but the non-slip teeth 6a and 20a
If is made finer, a function almost equivalent to stepless adjustment can be obtained. The non-slip teeth 6a may be provided on the entire outer peripheral surface of the involute cam 6 as shown in FIG. 6, or may be partially provided as shown in FIG. In addition, the non-slip teeth 6a may be provided only on the involute cam 6 as shown in FIG. 8A, or the non-slip teeth 20a may be provided only on the engagement member 20 as shown in FIG. In addition, the present invention is not limited to the above-described embodiment, and may be embodied by appropriately changing the shape and configuration of each part without departing from the spirit of the present invention.

[0026]

As described above in detail, according to the vehicle body supporting apparatus of the present invention, the pedestal is supported at the tip of the arm via the parallel crank mechanism, and the height of the pedestal is adjusted by the cam. Thus, the present invention has an excellent effect that it can be applied to a wide range of vehicles from a vehicle having a low lifting point to a vehicle having a high lifting point, and the height of the cradle can be adjusted in a short time by a simple operation.

[Brief description of the drawings]

FIG. 1 is a perspective view of a vehicle body support device according to an embodiment of the present invention.

FIG. 2 is a plan view of the same device.

FIG. 3 is a front view of the same device.

FIG. 4 is a diagram illustrating the operation of the device.

FIG. 5 is an operation explanatory view of the involute cam.

FIG. 6 is a front view showing a modification of the cam mechanism.

FIG. 7 is a front view showing another modification of the cam mechanism.

FIG. 8 is a front view showing still another modification of the cam mechanism.

FIG. 9 is a schematic view illustrating a lifting point of the automobile.

FIG. 10 is a sectional view showing a conventional vehicle body support device.

FIG. 11 is a sectional view showing a conventional vehicle body support device.

FIG. 12 is a sectional view showing a conventional vehicle body support device.

FIG. 13 is a sectional view showing a conventional vehicle body support device.

[Explanation of symbols]

1. Lifting platform, 2. Pinch panel of body, 3. Arm, 4. Cradle, 5. Parallel crank mechanism, 6. Involute cam, 6a ... Non-slip teeth, 14. Upper crank , 15 ... lower crank, 19 ... camshaft, 20 ...
Engaging member, 20a, non-slip teeth, 23, torsion spring, 2
Four knobs.

Claims (6)

[Claims] 1. A device for supporting a vehicle body in an automobile maintenance lift, comprising: an arm; a cradle for receiving the vehicle body at a tip end of the arm; and a parallel support for vertically supporting the cradle with respect to the arm in a horizontal posture. A body support device comprising a crank mechanism and a cam for adjusting the height of the cradle. 2. The vehicle body support for an automobile maintenance lift according to claim 1, wherein the cam is rotatably supported on one of the cranks of the parallel crank mechanism, and an engaging member is provided on the other crank for engaging with the cam. apparatus. 3. The vehicle body supporting apparatus for a vehicle maintenance lift according to claim 2, wherein a non-slip tooth is provided on at least one contact surface of the cam and the engaging member. 4. The vehicle body support apparatus for a lift for automobile maintenance according to claim 1, further comprising a spring member for urging the cam toward the large-diameter portion. 5. The vehicle body support device for a car maintenance lift according to claim 4, further comprising an operation member for rotating the cam toward the small-diameter portion side against a biasing force of a spring member. 6. The vehicle body supporting device for a lift for automobile maintenance according to claim 1, wherein an involute cam whose lift amount continuously changes is used as said cam.