JPH05281099A - Apparatus for supporting wheel of automobile on test base in order to measure wheel alignment of traveling unit and assembling method for supporting element - Google Patents

Abstract

PURPOSE: To enhance accuracy at the time of measuring or regulating a traveling unit by a structure wherein an supporting element for wheel plate has a chamber being fed with pressurized liquid on a flat supporting face contiguously to the flat bottom face of the wheel plate. CONSTITUTION: A supporting element comprises a tubular support 4 being fitted in the hole 5 of a substrate 1 and provided, at the upper end thereof, with an annular flange 6. The supporting element is fed with pressurized water through a connection hole 9 and a wheel plate 3 is lifted to provide a gap with respect to a supporting face 7. The pressurized water passes through the gap and flows from a recess 8 into an annular groove 10. When a pump is operated, the plate 3 is lifted continuously and floated on the liquid. Consequently, a traveling vehicle is fully relaxed and measurement of shape and regulation of the traveling unit can be performed with high accuracy. After finishing introduction of to the pressurized liquid, the plate 3 abuts on the supporting face 7 and the traveling vehicle can ride on the plate 3 or descend therefrom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a wheel plate arranged at a distance of approximately a wheel distance of a vehicle to be measured, and wheels of the vehicle are directly or indirectly placed on the wheel plate. Assembly of a support device and its supporting elements for supporting a vehicle wheel on a test stand for measuring the wheel alignment of a vehicle running device which is movably supported relative to the base in a substantially horizontal plane. Regarding the method.

[0002]

2. Description of the Related Art A test bench for measuring the wheel alignment of a traveling device is used, for example, in a vehicle assembly plant to detect and adjust the toe-in, camber angle and caster angle of the front and rear wheels of the traveling vehicle. Has been done. The adjustment in this case is generally made in consideration of the loop driving compensation, the symmetry axis of the vehicle, the steering wheel position and the actual elastic strain state. In order to measure the traveling device, the vehicle is sought to be placed on a test bench with the traveling device completely relaxed. This is ideally possible only when there is no friction between the tire and the floor. In order to achieve this, it is known to place the wheels of the vehicle on a wheel plate which is movably supported in a generally horizontal plane on the test bench with as little friction as possible.

To this end, ball bearings or multiple rolling bearings which have been movable in two planes and in one plane of rotation have heretofore been used. This known support device has the disadvantage that the initial release torque must be overcome as the wheel plate moves from the rest position. This results in the traveling device being able to be loosened only when the forces produced during the measurement and adjustment are greater than the forces required to initially release the support device. When the force is less than the initial release force, this causes a residual tension in the running gear, which causes deviations in measurement and adjustment. Due to the above reasons, it is not possible to obtain a measurement or adjustment result that is accurately reproduced. Furthermore,
Rolling bearings have the drawback that the coefficient of adhesive friction increases with time and gradually requires a large initial release force. Test benches with rolling bearings must therefore be serviced at very short intervals.

[0004]

The object of the present invention is to test the wheel alignment of a traveling device of the type mentioned at the beginning as characterized by a small coefficient of friction which is largely unaffected by the movement of the wheel plates. An object is to provide a device for supporting the wheels of an automobile on a platform.

[0005]

According to the invention, this object is achieved in that the wheel plate is supported on one or more support elements, which support element adjoins on the flat support surface the flat bottom surface of the wheel plate. This is achieved by having a chamber to which the pressurized liquid is supplied. By supporting the wheel plate according to the invention on a test stand for measuring the wheel alignment of the traveling device, the accuracy in measuring and adjusting the traveling device is clearly improved,
The long-term stability and thus the reproducibility is significantly improved compared to the hitherto known rolling bearings. This is due, on the one hand, to the fact that the coefficient of friction of the liquid support device is almost uniformly low in stationary and in motion of the wheel plate, so that no significant initial release force occurs. The liquid support element works almost without friction, thereby avoiding start-up effects. Furthermore, the mass to be moved is reduced by the liquid support device, which likewise contributes to an increase in the measuring accuracy.

In order to obtain the highest possible stability of the support device, in an embodiment of the invention, each wheel plate is supported by a plurality of liquid support elements spaced apart from one another. It is proposed that the support surfaces lie in a common plane. Furthermore, it is proposed that the support surface of the support element comprises a coating layer of synthetic resin, in particular polyamide. This avoids damage to the support element and the wheel plate when loading under pressureless conditions.

In another embodiment of the invention, it is proposed that the support element is connected to the base by means of a hardening filler. This coupling scheme allows the support elements to be easily aligned in one plane. This alignment is achieved according to another embodiment of the invention in that the support element is supported on the base by a liquid support device which compensates for height differences and angular errors. The alignment of the support elements in a common plane ensures that the support gaps in all the support elements of the wheel plate are of the same size everywhere. This avoids mechanical contact between the wheel plate and the support element. The individual wheel plates of the test stand do not have to be precisely located in a common horizontal plane, it is sufficient that the wheel plates are aligned substantially parallel to each other.

According to the invention, on the other hand, the alignment of the support element is such that, during its assembly, the support element rests on a spring element which contacts the base and lifts it from this base. The intermediate chamber in between is filled with a hardening filler, such that the support elements are statically loaded by a matching plate which contacts all the supporting elements in a flat plane until the filler is hardened. The casting process of the intermediate chamber is then simplified by placing a casting ring surrounding the filling material around the support element.

In this case, the alignment is carried out individually for each wheel plate or together by two or more wheel plate support devices which are in contact with all the support elements. Further, the two wheel plate supporting devices for the traveling axle are aligned by the aligning plate,
The two alignment plates spaced apart from each other are once again aligned parallel to each other. If the wheel plate support device has only liquid support elements, it is recommended that the support elements be aligned parallel to the support elements of the second wheel plate support device. Advantageously, the base has, for example, a substrate associated with each wheel plate, which substrate is connected to the base by means of a device for compensating for wheel plate height differences and angular errors.

A wheel plate support device according to the present invention comprises:
It applies to wheel plates on which the wheels of the vehicle are placed indirectly as well as to test stands on which the wheels of the vehicle are rotated by their own drive or another drive. In this case, the wheel plate is provided with a drum motor, a brake motor, a drum brake motor or an idle wheel.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in the drawings. The supporting device shown in the figure comprises a substrate 1 which is rigidly connected to the base of a test stand. This board 1
On top of which are attached four hydrostatic support elements 2.
These support elements 2 are arranged at the corners of a square and carry a substantially square wheel plate 3. The wheel plate 3 overhangs the support element 2 in the area of its edges.
The wheel R is mounted on the wheel plate 3. The test stand (not shown) is provided with a support device which is shaped identically to the other wheel of the motor vehicle or to all the remaining wheels.

The support element 2 comprises a solid cylindrical support 4. The support 4 is fitted in a hole 5 in the substrate 1 and has an annular flange 6 at the upper end protruding from the substrate 1. This annular flange 6 forms with the end face of the support 4 a flat support face 7. There is a hollow cylindrical recess 8 in the center of the support surface 7, and this recess 8 has a connection hole 9
Is open. Furthermore, the support surface 7 is provided with an annular groove 10 concentric with the recess 8 and spaced from it.
This annular groove 10 has a plurality of return holes 11 penetrating the support 4.
It is connected to the. The support surface 7 is coated with a thin layer of synthetic resin. A spring element 12 is arranged between the annular flange 6 and the base plate 1. An intermediate chamber between the annular flange 6 and the base plate 1 on the radially inner and outer sides of the spring element 12 is filled with a hardening filler 13. This filler 13
Is surrounded by a casting ring 14. The filler 13 is constrained and molded by the casting ring 14 before being cured. The casting ring 14 is removed after the filling material 13 has hardened.

The support element 2 is supplied with pressurized liquid via a connection hole 9. The wheel plate 3 is lifted by the pressure of the pressurized liquid, whereby a support gap is created between the wheel plate 3 and the support surface 7, and the pressurized liquid flows out from the recess 8 through this support gap and is annularly formed in the entire surface direction. It flows into the groove 10. The annular groove 10 is connected to the container via a return hole 11. The pressurized liquid is returned from this container to the connection hole 9 by the pump. The wheel plate 3 remains lifted from the support element 2 while the pump is operating and the pressurized liquid is being supplied to the recess 8 at a sufficient pressure and in a sufficient amount, in which case the wheel plate 3 is in contact with the support element 2. It floats on a pressurized liquid cushion generated by almost frictionless.

When this floating state is generated in all supporting elements of the test stand and in all wheel plates, the friction between the wheels of the vehicle and the foundation is the minimum residual that exists due to the shear resistance of the pressurized liquid. The friction is also reduced, so that the vehicle is completely relaxed and the geometry and adjustment of the traveling device can be performed with high accuracy. Since the wheel plates can easily move with the vehicle in the presence of small friction by the action of external forces, the position of the vehicle on the test stand is fixed by a suitable holding device acting on the vehicle body or the vehicle.

When the introduction of the pressurized liquid is finished, the wheel plate 3 rests on the support element 2. In this case, the wheel plate 3 is locked in this position, so that the traveling vehicle can ride on and off the wheel plate 3. In order for the above-mentioned vehicle support device to work satisfactorily, it is necessary that the support surfaces 7 of all the support elements 2 lie in a substantially horizontal common plane. To achieve this easily, the support element 2 is bonded to the base substrate 1 of the test stand in the following way.

The support element 2 is first loosely fitted in the bore 5, the support element 2 with its annular flange 6 being a spring element 12.
To contact. The spring element 12 maintains an intermediate chamber between the annular flange 6 and the upper side of the base plate 1. Support element 2
The casting ring 14 that surrounds the annular flange 6 and the substrate 1
The leakage of the filling material 13 injected into the intermediate chamber between and is prevented. After casting of all the support elements 2 required for the support, a uniform distribution of the filling material 13 takes place with the spring elements 12 compressed by several pumping movements of the support elements 2. The support element 2 is then statically loaded by an object which contacts the flat surface of all support elements 2. This load causes the spring elements 2 to be somewhat strongly compressed into the individual support elements 2, so that all support elements 2 have their support surfaces 7 in uniform contact with the flat surface of the load object. This loading state is maintained until the filling material 13 hardens, whereby the support element 2 is firmly bonded to the substrate 1. Support element 2
Exists in a common plane regardless of the dimensional accuracy of the underframe, and thus satisfies the required hydrostatic pressure supporting effect. The casting ring 14 is removed after the casting resin 13 is cured. For easy separation of the casting ring 14, this casting ring 1
4 is provided with a separating layer, eg grease, before injection of the filling material in order to avoid sticking of the filling material 13. With the method described above, the support element 2 can be assembled in precise alignment while compensating for existing manufacturing errors by simple means and at low cost.

[0017]

According to the present invention, the precision in measuring and adjusting the traveling device is improved, and the long-term stability and thus the reproducibility are significantly improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a support device for supporting a vehicle wheel on a test stand for measuring wheel alignment of a traveling device.

2 is a partial cross-sectional view of a support element of the support device and its fixing structure in FIG.

[Explanation of symbols]

 1 Substrate 2 Supporting Element 3 Wheel Plate 7 Supporting Surface 8 Recess 13 Filler

Claims (8)

[Claims] 1. Wheel plates are arranged at a distance of approximately the wheel distance of the motor vehicle to be measured, on which the wheels of the motor vehicle are placed, respectively directly or indirectly, the wheel plates being in a substantially horizontal plane as a base. A support device for supporting a wheel of an automobile on a test stand for measuring a wheel alignment of a traveling device of the automobile, which is supported so as to be movable in the entire surface direction with respect to one another, includes one or more wheel plates (3). Has a chamber (8), which is supported by a support element (2) of the wheel, which support element (2) adjoins the flat bottom surface of the wheel plate (3) on a flat support surface (7) and is supplied with pressurized liquid. A support device for supporting the wheels of an automobile on a test stand in order to measure the wheel alignment of the traveling device of the automobile. 2. Support device according to claim 1, characterized in that the support surface (7) of the support element (2) is provided with a coating layer of synthetic resin, in particular of polyamide. 3. Each wheel plate (3) is supported on a plurality of support elements (2) spaced apart from one another, the support surfaces (7) of these support elements (2) lying in a common plane. Support device according to claim 1 or 2, characterized in that it is located. 4. A support device according to claim 1, wherein the support element (2) is connected to the base (1) by means of a hardening filler (13). 5. The support element (2) is supported on the base (1) by a liquid support device which compensates for height differences and angular errors.
Supporting device according to item 6. 6. A base has a base plate (1) attached to each wheel plate (3), said base plate (1) being connected to the base by means of a device for compensating the height and angular errors of the wheel plate (3). The support device according to claim 1, wherein the support device is provided. 7. A support element (2) is mounted on a spring element (12) which contacts the base (1) and lifts the support element (2) from this base (1), the support element (2) and the base. The intermediate chamber between (1) and (1) is filled with a hardening filler (13) and the supporting element (2) contacts all supporting elements (2) in a flat plane until the filling material (13) hardens. 7. A method for assembling a support element of a support device according to claim 1, wherein the support element is statically loaded by the alignment plate. 8. A method as claimed in claim 7, characterized in that a casting ring (14) surrounding the filling material (13) is placed around the support element (2).