JP6159457B1 - Wheel alignment inspection method - Google Patents

Abstract

An object of the present invention is to quickly inspect the cause of a wheel alignment defect. The cutting angles of the outer front wheel and the inner front wheel are measured in a state where the steering wheel is turned to the left so that the outer front wheel has a cutting angle of 20 ° (S2). Next, the cutting angles of the outer front wheel and the inner front wheel in a state where the steering wheel is turned to the right so that the outer front wheel has a cutting angle of 20 ° are measured (S3). Next, the cutting angles of the outer front wheel and the inner front wheel in a state where the handle is turned to the left so that the front wheel is fully locked are measured (S4). Next, the cutting angles of the outer front wheel and the inner front wheel when the handle is turned to the right so that the front wheel is fully locked are measured (S5). It is determined whether or not there is a cause for the knuckle arm bending based on the measurement results of the cutting angles of S2 and S3, and the state of the knuckle arm bending is determined based on the difference between the cutting angles of S4 and S5. [Selection] Figure 2

Description

  The present invention relates to a wheel alignment inspection method.

  It is important to inspect the cause of a problem in wheel alignment in a vehicle having four wheels such as an automobile in order to ensure stability during traveling and to suppress uneven wear of tires. As described in Patent Document 1, paragraphs 0023 to 0025 of Patent Document 1, the cause of a wheel alignment defect is inspected as follows. The difference between the difference in the cutting angle between the inner and outer rings when the handle is turned to the left to the full lock state and the difference between the turning angles between the inner and outer rings when the handle is turned to the right to the full lock state Evaluate. The same evaluation is performed even when the handle is cut to a cutting angle smaller than the full lock. Based on the two evaluation results, a distinction is made as to whether the rack is misaligned or the knuckle arm is bent. Next, as described in paragraphs 0028 to 0031 and Table 2 of Patent Document 1, there is a problem in either the left or right knuckle arm based on a comparison between the cutting angle measured during full lock and a reference value. The bend of the heel and knuckle arm is judged.

Japanese Patent No. 5945620

  The wheel alignment inspection is required to be performed quickly.

  An object of the present invention is to provide a wheel alignment inspection method capable of more quickly inspecting the cause of a defect in wheel alignment.

  In the wheel alignment inspection method of the present invention, one of the left front wheel and the right front wheel is rotated to one of the left side and the right side so that the turning angle is a predetermined angle smaller than the angle corresponding to the full lock. Based on at least the other turning angle of the left front wheel and the right front wheel to be measured, the probability that the wheel alignment is defective due to the knuckle arm bend is determined, and the wheel alignment is defective. When there is a high probability that the cause is a bend of the knuckle arm, the left front wheel and the right are measured with the front wheel rotated in the first direction that is either the left or the right so as to be fully locked. Before the measurement is made in a state where the cutting angle of the front wheel to be measured which is one of the front wheels and the front wheel is rotated in the second direction opposite to the first direction so as to be fully locked. The difference between the bending angle of the measured front wheel on the basis of a result of comparison with the first reference value, determines whether the measurement target front wheel knuckle arm is bent inwardly and which direction the outer.

  According to the present invention, first, the cause of the wheel alignment failure is based on at least the turning angle of the other front wheel when one of the front wheels is cut to the left or right so that the turning angle is a predetermined angle. It is possible to determine the probability of being a bend. Next, it is possible to determine how the knuckle arm on the measurement target front wheel side is bent based on the difference in the cutting angle of the measurement target front wheel when the front wheel is turned left and right so as to be fully locked. In this way, it is possible to quickly inspect the cause of the wheel alignment defect by relatively few steps.

  Further, in the present invention, the left front wheel cut angle measured in a state where the right front wheel is rotated in the first direction so that the cut angle is the predetermined angle is defined as the first cut angle, When the cutting angle of the right front wheel measured in a state rotated in the second direction opposite to the first direction so that the cutting angle becomes the first angle is the second cutting angle, the first cutting angle It is preferable to determine whether or not the cause of the failure in the wheel alignment is a bend of the knuckle arm based at least on the result of comparing the difference between the angle and the second cut angle with the second reference value. According to this, it is possible to appropriately determine whether or not the cause of the wheel alignment failure is the bending of the knuckle arm, based on the difference in the cutting angle.

It is a schematic block diagram of the motor vehicle used as the test object of the wheel alignment test method according to one embodiment of the present invention. It is a flowchart which shows the flow of the test | inspection method of this wheel alignment. FIG. 3A is a schematic configuration diagram of the steering mechanism of the automobile in FIG. 1, FIG. 3A shows a case where the steering wheel is turned to the left, and FIG. 3B shows a case where the steering wheel is turned to the right. FIG. 4A is a schematic configuration diagram of the steering mechanism of the automobile in FIG. 1, FIG. 4A is a case where an inner curve is generated in the left knuckle arm, and FIG. 4B is an outer curve in the left knuckle arm. Show the case. It is a schematic block diagram of the steering mechanism of the motor vehicle of FIG.

  A wheel alignment inspection method (hereinafter referred to as the present inspection method) according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic configuration of an automobile 1 that is an object of this inspection method. The automobile 1 has front wheels 2L (left front wheels) and 2R (right front wheels), rear wheels 3L and 3R, and a steering mechanism 10. The steering mechanism 10 includes a handle 20, a rack 11, tie rods 12L and 12R, and knuckle arms 13L and 13R. When the driver operates the handle 20, the rotation of the handle 20 is transmitted to the rack 11 via a pinion gear (not shown), and the rack 11 moves in the left-right direction. The movement of the rack 11 is transmitted to the knuckle arms 13L and 13R through the tie rods 12L and 12R, and the knuckle arms 13L and 13R rotate. As a result, the front wheels 2L and 2R rotate (see FIGS. 3A and 3B). The vehicle 1 is provided with various configurations for the driver to drive the vehicle 1, such as an engine, a transmission mechanism that transmits the driving force of the engine to the rear wheels 3 </ b> L and 3 </ b> R, and an operation unit other than the handle 20.

  Hereinafter, the term “full lock” refers to a state in which the handle 20 is cut to the left or right as much as possible, or is in a cut state. The outer front wheel or the inner front wheel means a front wheel that is disposed on the outer side or the inner side in the turning motion of the automobile 1 that occurs when the steering wheel 20 is turned to the left or right while the automobile 1 is running, among the front wheels 2L and 2R. Shall. The cutting angle of the front wheel means the rotation angle of the front wheel based on the straight traveling state shown in FIG. For example, the cutting angle of the front wheel indicates an angle indicated by α or β in FIG. 3 (a) or FIG. 3 (b). In FIG. 3 (a), α indicates the turning angle of the outer front wheel (front wheel 2R) when the front wheel is turned to the left. [Beta] in FIG. 3 (a) indicates the turning angle of the inner front wheel (front wheel 2L) when the front wheel is turned to the left. In FIG. 3 (b), α indicates the cutting angle of the outer front wheel (front wheel 2L) when the front wheel is cut to the right. Β in FIG. 3 (b) indicates the turning angle of the inner front wheel (front wheel 2R) when the front wheel is cut to the right. In the following, αn represents the turning angle of the inner front wheel, and βn represents the turning angle of the outer front wheel.

  In this inspection method, first, as shown in S1 of FIG. The pre-adjustment includes a step of installing the automobile 1 in the alignment tester device and a step of adjusting the toe of the rear wheels 3L and 3R so that the thrust line of the automobile 1 coincides with the geometric center line. Further, in this inspection method, it is assumed that the front wheels 2L and 2R take the straight traveling state shown in FIG. 1 when the handle 20 is in the center. For this reason, when the front wheels 2L and 2R do not take a straight traveling state when the handle 20 is at the center before the main inspection, the front wheels 2L and 2R take a straight traveling state when the handle 20 is at the center in the pre-adjustment. Thus, the lengths of the tie rods 12L and 12R may be adjusted.

  The alignment tester device (hereinafter referred to as “tester”) used in the present embodiment has the respective cutting angles of the front wheels 2L and 2R when the handle 20 is fully locked and when the cutting angle of the outer front wheel is 20 °. Can be measured. The state where the cutting angle of the outer front wheel is 20 ° refers to a state where the cutting angle of the outer front wheel is 20 ° (first angle). Note that the alignment tester device may be capable of measuring the respective turning angles of the front wheels 2L and 2R when the handle 20 is in a state where the turning angle of the inner front wheel is 20 °. In this case, the cutting angle of the front wheel 2L or 2R when the handle 20 is in the state of 20 ° of the outer front wheel in the following is replaced with the cutting angle of when the handle 20 is in the state of 20 ° of the inner front wheel. May be.

  Next, each angle of the outer front wheel (front wheel 2R) and the inner front wheel (front wheel 2L) when the handle 20 is turned leftward (first direction) so that the turning angle of the outer front wheel is 20 ° is measured by a tester. (S2). Next, each angle of the outer front wheel (front wheel 2L) and the inner front wheel (front wheel 2R) in a state where the handle 20 is cut to the right (second direction) so that the turning angle of the outer front wheel is 20 ° is measured by a tester. (S3).

  Next, each angle of the outer front wheel (front wheel 2R) and the inner front wheel (front wheel 2L) in a state where the handle 20 is turned to the left so as to be fully locked is measured by a tester (S4). Next, each angle of the outer front wheel (front wheel 2L) and the inner front wheel (front wheel 2R) in a state where the handle 20 is turned to the right so as to be fully locked is measured by a tester (S5).

  Next, based on the values measured and calculated in S1 to S5, it is determined whether or not a defect has occurred in the wheel alignment and, if a defect has occurred, the cause is determined (S6).

  The determination method in S6 will be described in detail. For this determination, δ1 = β1-β2, δ2 = β3-α2, and δ3 = β4-α1 are used. δ1 corresponds to the left-right difference in the turning angle of the inner front wheel when the handle 20 is rotated so that the turning angle of the outer front wheel is 20 °. δ2 corresponds to a difference (inside / outside difference) in the turning angle of the front wheel 2L when the handle 20 is rotated left and right so that the front wheel is fully locked. δ3 corresponds to a difference (inside / outside difference) in the turning angle of the front wheel 2R when the handle 20 is rotated left and right so that the front wheel is fully locked. Then, it is determined whether or not the absolute value | δ1 | of δ1 is 30 ′ (first reference value) or more. When | δ1 | is less than 30 ′, if there is a problem in the wheel alignment, it is determined that the cause is other than the knuckle arms 13L and 13R. For example, the cause is considered to be in any position other than the knuckle arms 13L and 13R, such as the position shift of the rack 11, the position shift of the side member, and the suspension member. On the other hand, when | δ1 | is 30 ′ or more, it is determined that there is a high probability that the knuckle arm 13L or 13R is bent.

  Next, δ2 is compared with the reference value L. L indicates the state in which the handle 20 is turned to the right so as to be fully locked from the cut angle of the inner front wheel (front wheel 2L) of the vehicle when the handle 20 is turned to the left so as to be fully locked. This is a reference value of a value obtained by subtracting the cutting angle of the outer front wheel (front wheel 2L) of the vehicle. For example, the reference value may be a value acquired based on past inspection results regarding the automobile 1 or other automobiles, or may be provided by the manufacturer of the automobile 1 as a setting value at the time of manufacture. When δ2 is smaller than L by a certain amount (for example, δ2−L ≦ −2 ° is satisfied), it is determined that the knuckle arm 13L is bent outward. On the other hand, when δ2 is larger than L by a certain amount (for example, δ2-L ≧ 2 ° is satisfied), it is determined that the knuckle arm 13L is bent inward.

  Next, δ3 is compared with the reference value R. R is the value when the handle 20 is turned to the left so as to be fully locked from the turning angle of the inner front wheel (front wheel 2R) of the vehicle when the handle 20 is turned to the right so as to be fully locked. This is the reference value of the value obtained by subtracting the cutting angle of the outer front wheel (front wheel 2R) of the vehicle. For example, the reference value may be a value acquired based on past inspection results regarding the automobile 1 or other automobiles, or may be a value provided by the manufacturer of the automobile 1 as a setting value at the time of manufacture. May be. When δ3 is smaller than R by a certain amount (for example, δ3-R ≦ −2 ° is satisfied), it is determined that the knuckle arm 13R is bent outward. On the other hand, when δ3 is larger than R by a certain amount (for example, δ3-R ≧ 2 ° is satisfied), it is determined that the knuckle arm 13R is bent inward.

  The reason why the cause of the wheel alignment defect can be determined as described above will be described. This determination is based on the knowledge on the right: If there is a problem with the wheel alignment due to the misalignment of the rack 11 or the like, the turning angle at the time of full lock is likely to be shifted, while that at the time of not being full lock Deviations in the cutting angle are unlikely to occur. On the other hand, when the wheel alignment has a defect due to the bending of the knuckle arm 13L or 13R, the cutting angle is likely to be generated at both the full lock and the full lock.

  For example, it is assumed that the rack 11 is displaced in the left-right direction due to the displacement of the installation position of the rack 11 with respect to the vehicle body. In this case, as described above, the lengths of the tie rods 12L and 12R are adjusted such that when the handle 20 is at the center, the front wheels are correctly oriented in the straight traveling direction. FIG. 5 shows, as an example, when the rack 11 is shifted to the right, by adjusting the lengths of the tie rods 12L and 12R, the knuckle arms 2L and 2R, the left front wheel 2L, and the right front wheel 2R are directed straightly. Indicates the state. When the handle 20 is turned to the left or right from this state, the knuckle arms 13L and 13R rotate through the tie rods 12L and 12R according to the movement of the rack 11. When there is no abnormality in the knuckle arms 12L and 12R, the knuckle arms 12L and 12R rotate almost normally as the rack 11 moves. For this reason, for example, when the front wheel is at any turning angle until it is close to full lock, the front wheel turning angle is unlikely to deviate from the normal angle. However, if the handle 20 is rotated until the front wheels are fully locked, the initial position of the rack 11 is shifted, so that the position of the rack 11 when fully locked is also shifted from the normal position. . Therefore, when the front wheel is near full lock, the turning angle tends to deviate from the normal angle.

  On the other hand, when the knuckle arm 13L or 13R is bent as shown in FIG. 4, the amount of rotation of the knuckle arm 13L or 13R with respect to the movement of the rack 11 by a predetermined amount (the amount of change in the rotation angle) Deviation from the rotation amount when the knuckle arm is normal occurs. The deviation of the rotation amount occurs from the beginning of turning the handle 20, and becomes larger as the front wheel approaches the full lock state. Therefore, when the knuckle arm 13L or 13R is bent, the deviation from the normal knuckle arm at the turning angle of the front wheel 2L or 2R starts until the front wheel becomes fully locked after the handle 20 starts to be cut. The cut angle in the middle of, for example, a 20 ° cut angle is also somewhat large. The deviation increases as the front wheel turning angle increases. Further, when the knuckle arm 13L is bent, a difference from the reference value L occurs in the difference δ2 in the turning angle between when the front wheel 2L is turned to the left until it is fully locked and when it is turned to the right. Whether the deviation from the reference value L becomes positive or negative depends on whether the bending of the knuckle arm 13L is outside or inside. Further, when the knuckle arm 13R is bent, a difference from the reference value R occurs in the difference δ3 in the turning angle between when the front wheel 2R is turned to the left until it is fully locked and when it is turned to the right. Whether the deviation from the reference value R becomes positive or negative depends on whether the bending of the knuckle arm 13R is outside or inside.

  According to the present embodiment described above, δ1 to δ3 are calculated, and by comparing these with reference values, it is possible to measure whether the left or right knuckle arm is bent in the inner or outer direction. Therefore, it is possible to quickly inspect the cause of the failure in the wheel alignment with relatively few steps.

  Hereinafter, modifications of the above-described embodiment will be described. In the embodiment described above, when | δ1 | is 30 ′ or more based on the left / right difference δ1 = β1−β2 of the inner front wheel turning angle when the outer front wheel turning angle is 20 °, the knuckle arm 13L or It is determined that there is a high probability that 13R is bent. However, this determination may be performed based on each of β1 and β2. For example, it is assumed that the reference value (normal value) of the left front wheel turning angle when the handle 20 is turned to the left so that the turning angle of the right front wheel is 20 ° is 21 °. Such a reference value may be, for example, a value acquired based on past inspection results regarding the automobile 1 or other automobiles, or may be provided by the manufacturer of the automobile 1 as a set value at the time of manufacture. At this time, if the absolute value of the difference between β1 and the reference value 21 ° is 30 ′ or more, it may be determined that there is a high probability that the knuckle arm 13L or 13R is bent at that time. . The same applies when β2 is used instead of β1. This determination can be made when the angle of the rack 11 is shifted when the angle of the inner front wheel is deviated by a predetermined amount or more from the reference value when the angle of the outer front wheel is 20 °. This is because the probability that the knuckle arm 13L or 13R is bent is high. In addition, whether or not the knuckle arm 13L or 13R is bent is based on both β1 and β2 and the cutting angles α1, α2, β3, and β4 measured when the front wheels are in full lock. It may be determined. For example, it is determined whether or not the knuckle arm 13L or 13R is bent based on both the left and right difference Δ = α1−α2−β3 + β4 and δ1 when the front wheel is in full lock. Also good. As a specific example, when | α1−α2−β3 + β4 | ≧ 1 ° and | δ1 | ≧ 30 ′, it may be determined that the probability due to the bending of the knuckle arm 13L or 13R is high.

  In the above-described embodiment, the handle 20 is rotated so that the cutting angle of the outer front wheel is 20 ° in the steps S2 and S3 in FIG. However, in the steps S2 and S3 in FIG. 2, if the cutting angle is smaller than the cutting angle corresponding to full lock, the handle 20 is rotated so that the cutting angle of the outer front wheel is different from 20 °. May be.

2L, 2R Front wheel 3L, 3R Rear wheel 10 Steering mechanism 11 Rack 12L, 12R Tie rod 13L, 13R Knuckle arm

Claims (2)

The other of the left front wheel and the right front wheel measured with one of the left front wheel and the right front wheel rotated to the left or right so that the turning angle is a predetermined angle smaller than the angle corresponding to full lock Based on at least the turning angle of the wheel, determine the probability that the cause of the wheel alignment failure is the bending of the knuckle arm,
When there is a high probability that the cause of the wheel alignment failure is a knuckle arm bend, the front wheel is rotated in the first direction, either left or right, to be fully locked. Measured in a state in which the cutting angle of the front wheel to be measured which is one of the left front wheel and the right front wheel and the front wheel is rotated in a second direction opposite to the first direction so as to be fully locked It is characterized in that it is determined whether the knuckle arm on the measurement target front wheel side is bent in the inner side or the outer direction based on a result obtained by comparing a difference between the cutting angle of the measurement target front wheel and the first reference value. Wheel alignment inspection method. The left front wheel cut angle measured in a state where the right front wheel is rotated in the first direction so that the cut angle is the predetermined angle is defined as a first cut angle,
When the left front wheel is turned in the second direction opposite to the first direction so that the turning angle is the first angle, the cutting angle of the right front wheel is set as the second cutting angle.
Determining whether the cause of the wheel alignment failure is a knuckle arm bend based at least on the result of comparing the difference between the first cut angle and the second cut angle with a second reference value. The wheel alignment inspection method according to claim 1.

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