Wheel alignment measuring tool

Abstract

To provide a wheel alignment measuring tool that can measure a toe angle upon steering easily and accurately.SOLUTION: A wheel alignment measuring tool comprises: a pair of frame parts 110 that is attached to hub faces 30 of right and left steering wheels of a vehicle; and a pair of poles 116 that is supported from the frame part 110, and is to attach a pair of angle measurement means 120a and 120b. The poles 116 are arranged so as to be parallel relative to the hub face 30, and extend in a back and forth direction of a vehicle. At least one of the poles 116 is configured to be slidable in an axial direction, and thus, even in a state where the steering wheel is steered, the pair of angle measurement means 120a and 120b can be arranged in a position enabling an angle measurement.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the measurement of wheel alignment, and particularly to a measuring tool for easily and accurately measuring the toe angle during steering.

Background Art

[0002] Conventionally, the measurement of wheel alignment has been widely carried out. Many of them are performed for the purpose of ensuring the driving stability during straight-ahead driving at the upright position of the steering wheel or preventing uneven wear of the tires.

[0003] Also, the measurement of dynamic wheel alignment has been carried out. Many of them attempt to measure the changes in various alignments accompanying the vertical movement of the wheels with respect to the vehicle body in consideration of the changes in the vertical movement of the wheels (see Non-Patent Document 1).

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, while this may not apply to vehicles intended for use on public roads, vehicles used in various motorsports competitions (such as circuit racing, rallies, gymkhana, and drifting) are often not in a straight-ahead position while driving. In other words, since the steering wheel is turned for most of the time while driving, the alignment when the steering wheel is turned (when steering) is more important than the alignment when the steering wheel is upright (when driving straight), and there is a demand to accurately measure the alignment when steering (especially the toe angle, which is difficult to measure when steering).

[0006] Toe angle is generally measured using an instrument called a "toe-in gauge" (see Non-Patent Literature 2 and Figure 8). As shown in Figure 8, a conventional toe-in gauge 10 is constructed with angle measuring means 12 attached to the ends of a pair of frames 10a and 10b. Various types of angle measuring means exist, but for example, one consists of a laser irradiation unit 12a and a reflector 12b, and measures the angle from the position where the laser emitted from the laser irradiation unit 12a is reflected back by the reflector 12b.

[0007] As shown in Figure 8(a), this conventional toe-in gauge 10 is first set up so that the angle measuring means 12a and 12b are parallel, with the pair of frames 10a and 10b aligned with a parallel reference or the like (calibration).

[0008] Then, each is set on the front wheel of the vehicle. If the toe angle of both wheels is "0°", there is no change. However, if the toe angle is not "0°" (for example, if the left and right front wheels are facing inward (α, β) respectively), the reflector 12b will be non-parallel to the laser irradiation unit 12a. From that state, if the angle of the reflector 12b is adjusted so that it is parallel to the laser irradiation unit 12a, as shown in Figure 8(b), the adjusted angle γ will appear as the toe angle (total toe angle).

[0009] However, conventional toe-in gauges are designed with the steering wheel in the upright position (when driving straight), so when steering, the position of the angle measuring means (laser irradiation unit 12a and reflector 12b) shifts significantly, making measurement impossible. In addition, when steering, the vehicle positioned between the angle measuring means (laser irradiation unit 12a and reflector 12b) gets in the way, making measurement difficult.

[0010] Therefore, the present invention has been made to solve these problems, and aims to provide a wheel alignment measuring tool that can easily and accurately measure the toe angle during steering. [Means for solving the problem]

[0011] To solve the above problems, the present invention provides a pair of frame parts (a first frame part and a second frame part) to be attached to the hub surface or wheel surface of the left and right steering wheels of an automobile, a first pole supported by the first frame part and for attaching one of a pair of angle measuring means, and a second pole supported by the second frame part and for attaching the other of a pair of angle measuring means, wherein the first and second poles are arranged parallel to the hub surface or wheel surface and extend in the front-rear direction of the automobile, and at least one of the first and second poles is configured to be slidable in the axial direction, so that even when the steering wheels are steered, one and the other of the pair of angle measuring means can be positioned in a position where angle measurement is possible.

[0012] Similarly, the device comprises a pair of frame parts (a first frame part and a second frame part) attached to the hub surfaces or wheel surfaces of the left and right steering wheels of an automobile, a first pole supported by the first frame part and for attaching one of a pair of angle measuring means, and a second pole supported by the second frame part and for attaching the other of a pair of angle measuring means, wherein the first and second poles are arranged parallel to the hub surface or wheel surface and extend in the longitudinal direction of the automobile, and at least one of the pair of angle measuring means is configured to slide to a desired position on the pole, so that even when the steering wheels are steered, one and the other of the pair of angle measuring means can be positioned in a position where angle measurement is possible.

[0013] In this way, by sliding the pole itself axially, or by sliding the angle measuring means to a desired position on the pole, the misalignment between one and the other angle measuring means caused by steering can be eliminated, and furthermore, the vehicle itself can avoid interfering with the measurement. As a result, the inclination between the left and right steering wheels (total toe angle) can be easily and accurately measured regardless of the steering state.

[0014] Furthermore, when the frame portion is attached to the hub surface for measurement, it is desirable that the frame portion be supported from the floor surface via a rotating plate capable of measuring the rotation angle.

[0015] This configuration makes it easy to understand the steering wheel's rotation angle and the steering angles of the left and right steering wheels.

[0016] Furthermore, it is preferable that the rotating plate be placed on a horizontal stage.

[0017] This configuration allows for a more accurate determination of the steering angles of the left and right steering wheels. [Effects of the Invention]

[0018] By applying the present invention, it is possible to provide a wheel alignment measuring tool that can easily and accurately measure the toe angle (total toe angle) during steering.

Brief Description of the Drawings

[0019] [Figure 1] FIG. 8 is a front view of a wheel alignment measuring tool that is an example of an embodiment of the present invention. [Figure 2] It is a perspective view of the same. [Figure 3] FIG. 14 is a cross-sectional view of the holder and the pole taken along line III-III of FIG. 1. [Figure 4] FIG. 17 is a schematic view showing a state in which the wheel alignment measuring tool is attached in the upright state of the steering wheel. [Figure 5] FIG. 20 is a schematic view showing an example of a state in which the vehicle is steered with the wheel alignment measuring tool attached. [Figure 6] FIG. 23 is a view showing a state in which the pole is slid and the pair of angle measuring means are arranged at a measurable position. [Figure 7] FIG. 26 is a reference photo of a state in which the wheel alignment measuring tool is actually attached to a vehicle. [Figure 8] FIG. 29 is a schematic view showing measurement by a conventional toe gauge.

Mode for Carrying Out the Invention

[0020] Hereinafter, a wheel alignment measuring tool 100 that is an example of an embodiment of the present invention will be described while referring to the accompanying drawings. Note that, for easy understanding of the drawings, there are parts where the sizes and dimensions of each part are exaggerated and do not necessarily match the actual product. Also, each drawing is to be viewed in the direction of the reference numerals, and the up, down, left, right, front, and rear are expressed based on this direction.

[0021] 〈Configuration of Wheel Alignment Measuring Tool〉 As shown in Figures 1 and 2, the wheel alignment measuring tool 100, shown as an example of an embodiment of the present invention, is based on a frame portion 110 that is attached to the hub surface of the steering wheel 30 of an automobile. In this embodiment, the frame portion 110 is formed in a substantially trapezoidal shape with a circular upper part and has two legs 112 at the bottom. A large through hole 111a formed in the upper center of the frame portion 110 is a hole to accommodate the central projection of the vehicle's hub. Multiple holes formed around it are bolt holes 111b for passing bolts or wheel bolts protruding from the hub.

[0022] An offset plate 113 extending in the width direction of the vehicle is attached to the lower part of the frame 110. The mounting height of this offset plate 113 can be changed in stages depending on the usage situation.

[0023] An angle adjustment plate 114 is attached to the tip of the offset plate 113. Furthermore, the angle adjustment plate 114 is equipped with two holders 115, and a pole 116 is attached via these two holders 115. The pole 116 is fixed by a wing nut 115b that is screwed into a screw hole 115a formed in the holder 115 (see Figure 3), so that the pole 116 can be axially slid or rotated by loosening the wing nut 115b. In addition, the hub side surface 115c of the through hole through which the pole 116 passes in the holder 115 is, for example, V-cut when viewed in cross-section (see Figure 3), so that when the wing nut 115b is tightened and fixed, it automatically settles into the optimal position (height).

[0024] Furthermore, the hub side surface 115c is not necessarily limited to a V-shaped cut; for example, it can also employ a configuration that combines circles of different radii so that the pole 116 is precisely positioned by tightening. Specifically, the shape of the hub side surface 115c on the inner circumference of the through hole is configured such that a smaller circle (matching the radius of the pole 116) is combined with a larger circle, and the pole 116 is naturally positioned in the area formed by that smaller radius by tightening.

[0025] Furthermore, the angle adjustment plate 114 allows for fine adjustment of the tilt of the pole 116's axis as needed. The pole 116's axis is configured to always be parallel to the vehicle's hub surface (this parallel state is maintained even when the tilt of the pole 116's axis is finely adjusted using the angle adjustment plate 114).

[0026] Although not shown in Figures 1 and 2, one or the other of a pair of angle measuring devices is attached to the tip of the pole 116. The contents of the pair of angle measuring devices are not particularly limited; they can be any pair that can measure an angle, such as a laser irradiator and a reflector.

[0027] Furthermore, when using the wheel alignment measuring device 100, a rotating plate 130 capable of measuring the rotation angle is placed below the frame portion 110, and the device is used in such a manner that it is supported from the floor surface via a horizontal stage 140 below the rotating plate 130.

[0028] The wheel alignment measuring tool 100 according to the present invention functions as a set of two (two identical or mirror-image devices) having the configuration described above. Therefore, one of the angle measuring means is attached to one device, and the other of the angle measuring means is attached to the other device.

[0029] <The function and operation of wheel alignment measuring tools> Next, with reference to Figures 4 to 6, the procedure for measuring the toe angle (total toe angle) during steering using the wheel alignment measuring tool 100, which is shown as an example of an embodiment of the present invention, will be explained.

[0030] First, one of the pair of angle measuring instruments 120, 120a and the other 120b, is attached to the pair of wheel alignment measuring instruments 100. Then, the pair of wheel alignment measuring instruments 100 is fixed to a reference (parallel reference) where parallelism is guaranteed in advance, and calibration is performed so that the two poles 116 are parallel (specifically, for example, the values ​​of the angle gauges of the attached pair of angle measuring instruments 120a and 120b are set to zero (=parallel)).

[0031] After calibration, the frame portion 110 is attached to the hub surfaces 30 of the left and right steering wheels of the automobile. By attaching the frame portion 110 to the hub surfaces 30, the attached hub surfaces 30 and the pole 116 become parallel as described above (see Figure 4).

[0032] Next, with the steering wheel in the upright position (straight-ahead position), check that the steering wheels are pointing in the straight direction. If there is a discrepancy between the upright position of the steering wheel and the straight-ahead position of the steering wheels, it is desirable to adjust it at that point until they match. This is because modern cars have sensors on the steering wheel that detect whether the vehicle is going straight or steering, and perform various electronic controls accordingly. Therefore, it is necessary to match the straight-ahead position of the steering wheel with the straight-ahead position of the steering wheels. In the case of older cars that do not have such sensors, set the steering wheels to the straight-ahead position and proceed with the measurement.

[0033] Check the toe angle (total toe angle) of the steering wheels with the steering wheel in the upright position (straight-ahead position). Specifically, measure the angle using a pair of angle measuring instruments 120. At this time, if the toe angles of both steering wheels are "0°", there is no change from the calibration period.

[0034] Afterward, the steering wheel is operated to fix it in the desired steering position (see Figure 5). For example, even if the hub surfaces 30 of the left and right steering wheels are parallel and the toe angle (total toe angle) is 0 degrees in a straight-ahead state, the parallelism is not maintained due to the influence of "Ackermann angle" and "kingpin angle" when steering, resulting in a difference between the left and right sides.

[0035] Furthermore, steering causes the pair of angle measuring devices 120a and 120b to shift significantly (see Figure 5), making it impossible to measure the angle in this state. To explain in more detail, in a straight-ahead driving state, the laser irradiator 120a, which is one of the pair of angle measuring devices, is in a position where it is reflected in the reflector 120b, which is the other of the pair of angle measuring devices. However, in a steering state, it is not reflected in the mirror, making measurement impossible.

[0036] As shown in Figure 6, by sliding one or both poles 116 in the front-rear direction and adjusting the pair of angle measuring means 120a and 120b to a position where angle measurement is possible, it becomes possible to easily measure the toe angle (total toe angle) during steering.

[0037] As described in the above configuration, the present invention is characterized by comprising a pair of (two) frame portions 110 (a first frame portion and a second frame portion) attached to the hub surfaces 30 of the left and right steering wheels of an automobile, a first pole 160 supported by the first frame portion 110 and for attaching one of a pair of angle measuring means 120a, and a second pole 116 supported by the second frame portion 110 and for attaching the other of a pair of angle measuring means 120b, wherein the first and second poles 116 are arranged parallel to the hub surface 30 and extend in the front-rear direction of the automobile, and at least one of the first and second poles 116 is configured to slide in the axial direction, so that one of the pair of angle measuring means 120a and the other 120b can be positioned to measure angles even when the steering wheels are steered.

[0038] In this way, by sliding the pole 116 itself in the axial direction, the misalignment between one angle measuring means 120a and the other 120b caused by steering can be eliminated, and furthermore, the vehicle itself can avoid interfering with the measurement. As a result, the inclination (total toe angle) between the left and right steering wheels (hub surfaces 30) can be easily and accurately measured regardless of the steering state.

[0039] Furthermore, when the frame portion is attached to the hub surface for measurement, it is desirable that the frame portion be supported from the floor surface via a rotating plate capable of measuring the rotation angle.

[0040] This configuration makes it easy to understand the relationship between the steering wheel's rotation angle and the steering angles of the left and right steering wheels.

[0041] Furthermore, it is preferable that the rotating plate be placed on a horizontal stage.

[0042] This configuration allows for a more accurate determination of the steering angles of the left and right steering wheels.

[0043] <Other configuration examples> Although the above description assumes that the frame portion 110 is directly attached to the hub surface 30 of the vehicle, a configuration in which it is attached to the wheel (wheel surface) may also be adopted.

[0044] Furthermore, while the above description used an angle meter as a pair of angle measurement tools, it is also possible to use a distance meter instead of an angle meter and calculate the angle based on the data obtained.

[0045] Furthermore, it is desirable to set the pole 116 at a height that does not come into contact with the vehicle when the steering is performed.

[0046] Furthermore, although the above description assumed that the pole 116 itself slides in the front-to-back direction, a configuration may also be adopted in which the pole 116 is lengthened and at least one of the pair of angle measuring means 120a and 120b is slid to a desired position on the pole 116. Specifically, the vehicle comprises a pair of (two) frame sections 110 (a first frame section and a second frame section) attached to the hub surfaces 30 of the left and right steering wheels of the automobile, a first pole 116 supported by the first frame section 110 and for attaching one of a pair of angle measuring means 120a, and a second pole 116 supported by the second frame section 110 and for attaching the other of a pair of angle measuring means 120b. The first and second poles 116 are arranged parallel to the hub surface 30 and extending in the longitudinal direction of the automobile, and at least one of the pair of angle measuring means, either 120a or 120b, is configured to slide to a desired position on the pole 116. This configuration allows both 120a and 120b of the pair of angle measuring means to be positioned in a position where angle measurement is possible, even when the steering wheels are steered. [Explanation of symbols]

[0047] 30...Hub surface 100... Wheel alignment measuring tool 110... Frame section 113...Offset Plate 114...Angle adjustment plate 115... Holder 116... Paul 120... A pair of angle measuring means 130... Rotating Table 140... Horizontal stage

Claims

1. A first frame portion and a second frame portion, which are a pair of frame portions attached to the hub surface or wheel surface of the left and right steering wheels of an automobile, It is supported by the first frame portion and includes a first pole for attaching one of a pair of angle measuring means, It is supported by the second frame portion and includes a second pole for attaching the other of the pair of angle measuring means, The first and second poles are arranged parallel to the hub surface or wheel surface and extending in the longitudinal direction of the vehicle, By configuring at least one of the first and second poles to be slidable in the axial direction and rotatable along that axis, one and the other of the pair of angle measuring means can be positioned to measure angles even when the steering wheel is steered. A wheel alignment measuring tool characterized by the following features.

2. In claim 1, When measuring with the frame portion attached to the hub surface, The frame portion is supported from the floor surface via a rotating plate capable of measuring the rotation angle. A wheel alignment measuring tool characterized by the following features.

3. In claim 2, The aforementioned rotating plate is placed on a horizontal stage. A wheel alignment measuring tool characterized by the following features.

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