JPH06331505A - Unbalance evaluation system for vehicle - Google Patents

Abstract

PURPOSE:To allow quantitative unbalance evaluation without relying on the feeling by providing an unbalance evaluation means for vehicle and a load cell fixed to a member supporting each correction wheel in a vehicle opposing mechanism of a wheel alignment tester. CONSTITUTION:As shown by arrow B, a wheel 2 advances onto a wheel alignment tester 1 and each wheel 3 is supported by the roller 4 of each wheel drive mechanism 5. An air cylinder 7 pulls a cylinder rod and a link mechanism 8 shifts each arm member 8a toward each wheel 8a. Each correction wheel 6 presses the lower side face of each wheel 3 from one side thereof thus correcting the orientation of the wheel 2 with respect to a tester 1. When an unbalance amount of vehicle, determined based on a data representative of correlation between the input load of a load cell 12 and the unbalance of vehicle, exceeds a preset value, a personal computor 13 a decision result of unacceptable to a monitor 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for evaluating the degree of one-sided flow of a vehicle caused by variations in tire characteristics when the vehicle is running with the steering wheel held straight.

[0002]

2. Description of the Related Art The above-mentioned evaluation of the degree of partial flow of a vehicle is
This is done to confirm the overall wheel alignment balance of a vehicle whose wheel alignment has been adjusted during the final inspection of the vehicle produced on the vehicle production line and the inspection of the vehicle after maintenance. In the conventional one-way flow evaluation of such a vehicle, an operator visually positions the steering wheel at a straight-ahead position, then performs a simulated run in which the vehicle travels a certain distance on a test course, and the vehicle runs during the simulated run. It was performed by a method of sensory evaluation of whether or not the course deviates to the left or right with respect to the straight direction.

[0003]

However, in the above-mentioned conventional evaluation method, it is difficult to perform quantitative evaluation because it depends on the sensory sense of the operator, and a wide test course is required, so There is a problem that it is difficult to evaluate in a narrow space such as a building of an inspection station.

By the way, a wheel alignment tester generally used for wheel alignment adjustment is
To measure the wheel alignment of each wheel of the vehicle, it has rollers that individually support and rotate each wheel, and the correction wheels corresponding to each wheel of the vehicle push each wheel from the side to fix the vehicle. The wheel alignment tester is provided with a vehicle facing mechanism that corrects the wheel into a correct position, and as a result of the research conducted by the present inventor, each wheel of the vehicle is rotated by the wheel alignment tester while being rotated. It was found that there is a certain correlation between the pressing force applied in reverse from the wheels and the one-sided flow rate of the vehicle.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned research results, and an object of the present invention is to provide an apparatus which advantageously solves the problems of the conventional one-way flow evaluation method. The evaluation device comprises a load cell attached to a member supporting each correction wheel of the vehicle facing mechanism of the wheel alignment tester, and a one-way flow evaluation means for evaluating the degree of one-way flow of the vehicle based on an output signal of the load cell. It is a matter of fact.

[0006]

In such an apparatus, the wheels of the vehicle to be evaluated, which have undergone the wheel alignment adjustment, are mounted on the rollers of the wheel alignment tester, and the vehicle facing mechanism of the wheel alignment tester adjusts the correction wheels. The wheels to be evaluated are brought into close contact with each other from the outside and the wheels are pressed from the outside, whereby the direction of the evaluated vehicle is maintained in the correct direction with respect to the wheel alignment tester, Each roller of the vehicle is continuously rotated by the roller, and during the rotation, the load cells of the evaluation device attached to the members supporting the respective correction wheels are reversely rotated from the respective wheels to the correction wheels. A signal corresponding to the pressing force applied to the load cell, and based on the output signals of the load cells, the one-way flow evaluation means of the evaluation device determines the one-way flow of the vehicle. To evaluate the degree.

Therefore, according to the apparatus of the present invention, it is possible to quantitatively evaluate the one-sided flow of the vehicle and also to evaluate the inside of a factory or an inspection site.

[0008]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 (a) is a front view showing an embodiment of a vehicle one-sided flow evaluation device of the present invention in a mounted state on a wheel alignment tester used for wheel alignment adjustment, and FIG. 1 (b) shows that embodiment. 2A to 2C are sectional views taken along the line AA of FIG. 1 showing the apparatus of the embodiment in different operating states, where 1 is a wheel. An alignment tester is shown.

In order to measure the wheel alignment of each wheel 3 of the vehicle 2, the wheel alignment tester 1 here rotates two rollers 4 supporting each wheel 3 separately by a motor (not shown). In order to correct the direction of the wheel drive mechanism 5 and the vehicle 2 to the correct direction with respect to the wheel alignment tester 1, a correction wheel 6 corresponding to each wheel 3 of the vehicle 2 is formed by the air cylinder 7 and the link mechanism 8. 3 for each wheel to advance to 3
The vehicle facing mechanism 9 that presses the vehicle from the side, and the distances to the three sides of the side surface of the tire of each wheel 3 are the front part near the front of the vehicle, the rear part near the rear of the vehicle and the upper part near the upper part of the vehicle with respect to the axle. A wheel attitude measuring device 10 which outputs data indicating the attitude of each wheel 3 with respect to the wheel alignment tester 1 and, in turn, the wheel alignment measured by ultrasonic waves,
It has a control panel 11 which incorporates a microcomputer and controls the operation of each of the above mechanisms in accordance with a predetermined procedure.

In the device of this embodiment, the link mechanism 8 of the vehicle facing mechanism 9 of the wheel alignment tester 1 is provided at an intermediate portion of an arm member 8a which rotatably supports each correction wheel 6 around a vertical axis. The load cell 12 is interposed, and the magnitude of the load applied to the arm member 8a by each wheel 3 via each correction wheel 6 and the direction in which the arm member 8a is retracted is measured as a uniaxial compression load applied to the load cell 12. And load those load cells 12 via the control panel 11 above.
It is configured such that it is electrically connected to a personal computer 13 as one-sided flow evaluation means, and a monitor device 14 is electrically connected to the personal computer 13. The load cell 12 may be an ordinary one that measures a uniaxial compressive load with a strain gauge, a piezoelectric element, or the like, and the personal computer 13 may be an ordinary one that has a CPU, a memory, or the like.

The wheel alignment tester 1 including the apparatus of the above embodiment adjusts the wheel alignment of each wheel 3 of the vehicle 2 and evaluates the one-sided flow of the vehicle according to the procedure shown in the flowchart of FIG. That is, here, first, in step 21, as shown by an arrow B in FIG.
2 (b), each wheel 3 of the vehicle 2 is supported by the roller 4 of each wheel drive mechanism 5, and then in step 22, the air cylinder of the vehicle facing mechanism 9 is supported. The link mechanism 8 advances each arm member 8a toward each wheel 3 by pulling in the cylinder rod by 7, and each correction wheel 6 presses the lower part of the side surface of the tire of each wheel 3 from the side. Then, the direction of the vehicle 2 is corrected (centered) to the correct direction with respect to the wheel alignment tester 1.

Next, here, in step 23, after the operator fixes the steering wheel in the straight-ahead position, each correction wheel 6 is moved to each wheel 3.
The wheel drive mechanism 5 rotates the rollers 4 to rotationally drive the wheels 3 in a state in which the wheel 4 is pressed to continue the centering, whereby the wheels 3 are continuously rotated while the wheels 3 are continuously rotating. The attitude measuring device 10 ultrasonically measures the distances to the front, rear and upper portions of the side surface of the tire of each wheel 3 and outputs data indicating the wheel alignment of each wheel 3, and the following step 24 Then, the control panel 11 displays those measurement results on its own display panel. Then, in the next step 25, the operator determines whether the vehicle 2 on the wheel alignment tester 1 is based on the displayed measurement result.
The alignment adjustment section of the suspension that supports each wheel 3 is adjusted so that the wheel alignment of each wheel 3 falls within the range of the specified value.

Then, in step 26, the wheel alignment measurement of each wheel 3 and the display of the measurement result are performed again in the same manner as in step 23 and step 24, and the wheel alignment of each wheel 3 falls within the specified range. While confirming that the vehicle has entered, while measuring the wheel alignment of each wheel 3, that is, while the wheels 3 are continuously rotating and the vehicle 2 is in a state close to actual traveling,
Each load cell 12 measures the uniaxial compressive load applied thereto, that is, the pressing force at which each wheel 3 reversely pushes each correction wheel 6 back toward the vehicle body, and outputs a signal corresponding to the pressing force. The output signal from each load cell 12 is input to the personal computer 13 via the control panel 11.

In the following step 27, the personal computer 13 measures the input load to each load cell 12 obtained from the output signal of each load cell 12 in advance, for example, as shown in FIG. Based on the data showing the correlation between load cell input load and vehicle one-sided flow collected by performing one-sided flow rate measurement on a common vehicle in the test, the vehicle one-sided flow rate (when the steering wheel is set to the straight running state and the vehicle travels 1000 m Is a value indicating how much is shifted to the right or left), and the vehicle one-side flow rate measured in this way is compared with a preset specified value (for example, 5 m / 1000 m in FIG. 4). As a result of this comparison, when the measured vehicle one-sided flow rate is equal to or more than the specified value, the process proceeds to step 28, and the personal computer
13 outputs a signal indicating the determination result of vehicle one-sided flow NG (defective) to the monitor device 14, and the monitor device 14 outputs the NG
The determination result is displayed on the screen together with the measured vehicle one-sided flow rate. Then, after that, returning to step 25, the worker re-adjusts the balance between the wheel alignments of the wheels 3 based on the measured vehicle one-sided flow amount so as to reduce the vehicle one-sided flow amount, and then measures the vehicle one-sided flow amount again. I do.

On the other hand, as a result of the comparison in step 27, if the measured vehicle one-sided flow amount is less than the specified value, the process proceeds to step 29, in which the personal computer 13 calls the vehicle one-sided flow OK (good). A signal indicating the determination result is output to the monitor device 14, and the monitor device 14 outputs the OK.
The determination result is displayed on the screen together with the measured vehicle one-side flow rate. Then, thereafter, in step 30, the air cylinder 7 of the vehicle facing mechanism 9 advances its cylinder rod, whereby the link mechanism 8 moves the respective arm members 8a backward to move the respective correction wheels 6 from the respective wheels 3. After separating,
As shown by an arrow C in FIG. 2C, the vehicle 2 exits from the wheel alignment tester 1.

Therefore, according to the wheel alignment tester 1 equipped with the apparatus of the above embodiment, the adjustment of the wheel alignment of the vehicle 2 and the evaluation of the partial flow can be performed by a series of operations on the tester. It is possible to reduce the man-hours required for. Moreover, according to the apparatus of the above-described embodiment, it is possible to perform a quantitative evaluation of one-sided flow without depending on the sensuality of the operator, so that the reliability of the evaluation can be increased and the evaluation is NG (defective). In this case, the readjustment can be performed accurately, and since a wide test course is not required because the evaluation is performed on the wheel alignment tester, it is easy to perform the evaluation in a narrow place such as a factory or an inspection site building. It can be carried out.

Although the invention has been described above with reference to the illustrated example, the invention is not limited to the above-described example. For example, if the wheel alignment tester provided with the device of the invention has a vehicle facing mechanism. Other than the above example, for example, a structure for performing wheel alignment measurement by changing the direction or inclination angle of the roller supporting the wheel may be used. Further, the load cell may be provided at any position of the member supporting the correction wheel as long as it can measure the pressing force from the correction wheel, and extends along the axis of the arm member 8a in the above example along the axis thereof, for example. The ball spline shaft is supported via a ball slider so as to be movable back and forth in the direction, and the correction wheel 6 is fixed to the tip end portion of the ball spline shaft, while the input portion of the load cell is attached to the rear end portion of the ball spline shaft. Alternatively, the main body of the load cell may be fixed to the rear end of the arm member 8a. Further, the one-sided flow evaluation means may be combined with the microcomputer in the control panel if possible in terms of calculation processing capability and the like.

[0018]

As described above, according to the vehicle one-sided flow evaluation apparatus of the present invention, the one-sided flow can be quantitatively evaluated without depending on the operator's sensuality, so that the certainty of the evaluation can be enhanced and the evaluation is poor. In the case of, the readjustment can be performed accurately, and since the evaluation is performed on the wheel alignment tester, a wide test course can be unnecessary, so
It is possible to easily perform evaluation in a narrow space such as a factory or a building of an inspection station.

[Brief description of drawings]

FIG. 1 (a) is a front view showing an embodiment of a vehicle one-sided flow evaluation apparatus of the present invention mounted on a wheel alignment tester used for wheel alignment adjustment, and FIG. 1 (b) is that embodiment. It is a top view of the apparatus of.

2 (a) to 2 (c) are cross-sectional views taken along the line AA of FIG. 1, showing the apparatus of the above embodiment in different operating states.

FIG. 3 is a flowchart showing a vehicle one-sided flow evaluation procedure by the apparatus of the above-described embodiment.

FIG. 4 is a relationship diagram showing an example of a correlation between an input load to each load cell and a vehicle one-sided flow amount in the device of the above embodiment.

[Explanation of symbols]

 1 wheel alignment tester 2 vehicle 3 wheel 6 correction wheel 8a arm member 9 vehicle facing mechanism 12 load cell 13 personal computer

Claims (1)

[Claims] 1. A load cell (12) attached to a member (8a) for supporting each correction wheel (6) of a vehicle facing mechanism (9) of a wheel alignment tester (1), and an output signal of the load cell. A vehicle one-sided flow evaluation apparatus comprising: a one-sided flow evaluation means (13) for evaluating the degree of one-sided flow of a vehicle based on the vehicle.