JPS61178607A - Measurement of toe of automobile - Google Patents

Abstract

PURPOSE:To effect accurate mounting of a steering wheel, by contacting measuring plates to side surfaces of LH and RH rear wheels and measuring, by inclination of these plates, front and rear directions of LH and RH rear wheels relative to the measuring reference axis parallel to the reference axis in the front and rear direction of the vehicle. CONSTITUTION:Measuring plates 1a, 2a fixed to measuring units 1, 2 are allowed to contact with the side surfaces of LH and RH rear wheels Wrr, Wrl of a vehicle BO and directions of the rear wheels Wrr, Wrl are measured. by measuring front and rear directions (Toe) of each rear wheel Wrr and Wrl relative to the measuring reference lines Lr, Ll parallel to the reference line LO of the measuring apparatus. Qrr, Qrl are determined respectively. As shown in the equation, 1/2 of the difference of Qrr, Qrl, values of LH and RH rear wheels Wrr, Wrl are determined as a value theta in the direction of the vehicle BO. Next, by using the value of theta, correction is made iof the toe reference value Qt iof the preset front wheels Wfr, Wfl. As the neutral position of a steering wheel is so made as the reference, the steering wheel can not be fixed in n inclined condition.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method for determining the toe of an automobile.

Toe of a car refers to the inclination of the wheels relative to the direction of travel when the car is viewed from above.Toe-in is when the wheels are tilted toward the front end of the vehicle or toward the inside of the vehicle relative to the direction of travel. This case is called toe-out.

Conventional technology As a method for measuring toe of this type of automobile, for example, Japanese Patent Application Laid-open No. 5
There is one shown in Publication No. 7-100307. According to this conventional method, as shown in FIG. 2, a sensor plate pressed against the side surface of each wheel detects the longitudinal direction A
, B, C, and D, and 1/2 of the difference between the values C and DO of the left and right rear wheels is calculated as vehicle B.

The process of determining 1/2 of the difference between the values A and 8 of the left and right front wheels as the value α of the direction of the front wheels, and each f of the left and right rear wheels.
The sum or difference between LC9D and the vehicle direction value β is the corrected toe value for the left and right rear wheels, and the sum or difference between the 6 values A and B of the left and right front wheels and the vehicle direction value β is the correction for the left and right front wheels. The difference between the front wheel direction value α and the vehicle direction value I is calculated as the front wheel direction with respect to the vehicle direction.

Problems to be Solved by the Invention According to the above conventional method, the modified toe values (A, B
The basic idea is to adjust the toe of the front wheels based on the sum or difference between the value of . In other words, you first need to orient the front wheels so that the vehicle will drive straight ahead, and then attach the steering wheel accordingly.

In this case, there is no guarantee that the relationship between the peaks and valleys of the serrations at the serration connection portion between the steering shaft and the steering wheel will necessarily match the neutral position of the steering wheel.

For this reason, for example, even though the front wheels are in a straight-ahead state, the steering wheel may be mounted at an angle of up to 1/2 rotation.

The present invention aims to provide a toe measurement method that solves the above-mentioned problems.

Means for Solving the Problems The present invention employs a method in which the steering wheel is fixed and held in a neutral position in advance, and then the toe is measured.

More specifically, as mentioned above, with the steering wheel fixed and held in the neutral position, a measurement plate is brought into contact with the side surfaces of the left and right rear wheels, and from the inclination of this measurement plate, a measurement standard parallel to the reference line in the longitudinal direction of the vehicle is determined. First, the longitudinal direction Qrrt of the left and right rear wheels with respect to Qrt is determined. Then, 1/2 of the difference between the left and right rear wheel values Qrr and QrlO is determined as the vehicle direction value θ, and the difference or sum between the vehicle direction value 0 and the preset toe reference value Qt of the left and right rear wheels is determined. By determining this, the cough toe reference value is corrected and toe adjustment target values Qr t t J t for the left and right front wheels are specified.

As described above, in the present invention, first, the steering wheel is fixed and held in the neutral position, and then the value of the direction of the vehicle is determined from the direction of the left and right rear wheels, and the toe reference value of the left and right front wheels is corrected based on this value of the direction of the vehicle. )-! Since the steering wheel is based on the II alignment reference value, there is no possibility that the steering wheel will be installed at an angle.

Embodiment FIGS. 1(5) and 1(B) are explanatory diagrams showing an embodiment of the method of the present invention.

As shown in FIG. 1(5), for the vehicle Bo positioned at a predetermined measurement position, a steering wheel connected to a steering shaft (not shown) through serrations is fixed and held at a neutral position by a predetermined jig.

Then, the measurement plates 1a and 2a attached to the measurement units 1 and 2 are brought into contact with the side surfaces of the left and right rear wheels Wrr and Wrl of the vehicle BO to measure the directions of the rear wheels Wrr and WrlO. That is, from the inclination of the measurement plates 1a and 2a,
The direction of each rear wheel Wrr, Wrl O in the longitudinal direction with respect to the measurement standards @Lr, Ll parallel to the reference line Lo of the measuring device (
) and set them as Qrr and Qrl, respectively.

Note that the measurement plates 3a and 4a of the measurement unit 3.4 are also kept in contact with the front wheels Wfr and Wfl.

Then, as shown in equation (1), the left and right rear wheels Wrr,
Wrl value Qrr, Qrl difference O1/21 vehicle Bo
(D direction is determined as 1 flil tD value θ.

Here, 0 assumes that the direction shown in FIG. 1 (5) is positive.

In other words, regardless of the actual orientation of the vehicle Bo, the rear wheels Wr
r, Wrl The θ direction determined by the O direction Qrr and Qrl is the straight direction of the vehicle.

Next, using the negative value, the preset front wheel Wf
Correct the toe reference value Qt of r and Wfl. The toe reference value Qt referred to here is a predetermined design value. In other words, as shown in equations (2) and (3), vehicle Bo
By calculating the sum of the direction value 0 and the toe reference value Qt of the right front wheel Wfr, the toe a14 adjustment target value Qrt of the right front wheel Wfr is determined.
On the other hand, find the difference between the direction value d of the vehicle Bo and the toe reference value Qt of the left front wheel WfJ (2) of the left front wheel Wf/
-84 set target value QAIt.

Right front wheel toe adjustment target value Qr t = Q t + θ ・
・Song (2) Left front wheel toe adjustment target fiQJt=Q by θ・
-Song (3) All of these calculations are performed by a computer.

Then, the left and right front wheels Wfr obtained as above
, Wfl O) - Display the adjustment target values Qrt, Ql visually, for example, and adjust the left and right front wheels Wfr, WfJ so that the actual measured values of the measurement units 3 and 4 match the toe adjustment target values Qrt, t. All you have to do is adjust the toe.

Effects of the Invention As described above, according to the present invention, the direction value of the vehicle determined by the direction of the rear wheels is determined, and the toe reference value of the front wheels is determined based on the above direction value while the steering wheel is fixed and held in the neutral position. By correcting this, the toe adjustment target value is specified. Therefore, since the neutral position of the steering wheel is the standard, unlike the conventional
The 4C steering wheel will not be installed tilted.

[Brief explanation of drawings]

FIG. 1 is an explanatory plan view of a vehicle showing an embodiment of the method of the present invention, FIG. 1(B) is a flowchart showing the calculation process, and FIG. 2 is an explanatory diagram of the conventional measuring method. 1.2, 3.4...Measuring unit, la, 2a. 3a, 4a... Measuring plate, Wfr, Wfl - Front wheel, Wrr. Wrl...Rear wheel, Lo...Reference line, Lr, Ll-
...Measurement reference line, θ...Vehicle direction value. advance notice

Claims (1)

[Claims] (1) With the steering wheel fixed and held in the neutral position in advance, a measurement plate is brought into contact with the sides of the left and right rear wheels, and the left and right rear wheels are measured based on the inclination of the measurement plate relative to the measurement reference line parallel to the longitudinal reference line of the vehicle. (Qrr, Qr
l), then calculate 1/2 of the difference between the left and right rear wheel values (Qrr, Qrl) as the vehicle direction value (θ), and calculate the vehicle direction value (θ) and the preset left and right front wheel values. Toe reference value (
A toe measurement method for an automobile, characterized in that the toe reference value is corrected by calculating the difference or sum of the toe adjustment value (Qrt, Qlt) for the left and right front wheels by calculating the difference or sum of the toe reference value and the toe adjustment target value (Qrt, Qlt) for the left and right front wheels.