JPH0511015U - Wheel alignment measuring device - Google Patents

Abstract

(57) [Summary] [Purpose] Accurately measure wheel alignment under various conditions. [Structure] The wheel alignment measuring device includes a pedestal 2 that supports a suspension unit 10 equipped with iron standard wheels 8 instead of a vehicle, and further mounts the standard wheels 8 on the pedestal 2. A turntable 24 that can move relatively is provided. The turntable 24 is moved up and down by a worm jack 30 and further horizontally loaded by a horizontal pressing mechanism 40. As a result, the standard wheel 8 has a turntable 24
Force is applied according to various running conditions. Further, the suspension frame 4 is provided with a measuring device for measuring the X, Y, Z axis coordinates of a specific point of the standard wheel 8 and the suspension unit 10, and the wheel alignment is performed based on the coordinates of the specific point. Desired.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a device for measuring wheel alignment in various driving states of a vehicle.

[0002]

[Prior Art]

 In addition to supporting the weight of each part of the vehicle body, the wheels of an automobile are attached to the axle with a certain geometrical angle for running stability and tire wear. This geometrical angle is called wheel alignment, and consists of four elements: toe angle, camber angle, caster angle and kingpin tilt angle. Conventionally, a method of measuring this wheel alignment is to set a tilt angle sensor on the wheel of the wheel and obtain the wheel alignment from the wheel tilt obtained indirectly by this tilt angle sensor, or to measure the wheel alignment. A method is used in which the coordinates of a specific point are measured with a measuring instrument, and the wheel alignment is obtained from the wheel tilt obtained directly from the coordinates of this specific point. For example, the toe angle and the camber angle are obtained from the wheel inclination obtained indirectly or directly, and the caster angle and the kingpin inclination angle are the inclination angle sensors when the wheel is cut straight from the straight state to the left or right. It is indirectly obtained from the change in the indicated value of. Furthermore, in order to measure changes in the wheel alignment during the bound and rebound conditions of the vehicle, the weight of a predetermined weight is sequentially placed on the hood and trunk, and the bound condition of the vehicle is simulated, or the vehicle is jacked. Measurements are being performed while mimicking the rebound state by, for example, popping up.

[0003]

[Problems to be solved by the device]

 However, according to the measuring method using the tilt angle sensor, when the tilt angle sensor is set on the wheel of the wheel, there is a problem that the measurement accuracy varies greatly due to the mounting error. Further, in the measuring method for measuring the coordinates of the specific point of the wheel, the vehicle body is an obstacle to the measurement when measuring the coordinates of the specific point of the wheel, and the workability is very poor. There is a problem that is not good. In addition, the method of sequentially mounting the weight of a predetermined weight on the vehicle or the method of jacking up cannot efficiently perform the measurement. In addition, it is almost impossible to measure the wheel alignment while the vehicle is running. Moreover, each component of the suspension system, which determines the wheel alignment, is hidden behind the wheel, so that it is not possible to observe each component sufficiently. The technical problem of the present invention is to add forces or displacements in various driving states to wheels and suspensions, and measure the three-dimensional coordinates of specific points necessary for wheel alignment measurement under these conditions. By making it possible, we are trying to improve the accuracy and efficiently measure the wheel alignment under various situations.

[0004]

[Means for Solving the Problems]

 The above-mentioned problems are solved by a wheel alignment measuring device having the following structures. That is, the wheel alignment measuring device according to the present invention mounts a pedestal that supports a suspension device equipped with wheels instead of a vehicle body and a wheel that is mounted on the suspension device supported by the pedestal, and mounts it on the pedestal. A movable table that is capable of relative movement with respect to the movable table, when the movable table is moved relative to the gantry by a predetermined distance, or when a predetermined force is applied between the movable table and the gantry. In the above, the vehicle has a wheel and a measuring mechanism for measuring the three-dimensional coordinates of a specific point of the suspension device.

[0005]

[Action]

 According to the present invention, the measurement accuracy is improved because the three-dimensional coordinates of the specific points of the wheel and the suspension are actually measured and the wheel alignment is obtained based on the coordinates of the specific points. Further, by moving the movable table up and down to displace the wheels mounted on the suspension device in the vertical direction (Z-axis direction), it is possible to measure the wheel alignment in the bound or rebound state of the vehicle. Further, by applying a predetermined force in the horizontal direction (X, Y axis direction) to the wheels via the movable table, it is possible to measure the wheel alignment in the acceleration / deceleration state of the vehicle or the curve traveling state. That is, this device enables the wheel alignment under various situations to be measured efficiently and accurately.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 4 shows an overall side view of the wheel alignment measuring device according to the present embodiment. The wheel alignment measuring device is provided with a base pedestal 2 which is assembled into a substantially rectangular parallelepiped shape with a steel material. A pair of rail guides 4 are provided on the base pedestal 2 in a direction perpendicular to the plane of the drawing (corresponding to the left-right direction of the vehicle (Y-axis direction)). The movable column portion 6 assembled in the above is mounted so as to be movable only in the Y-axis direction. During the wheel alignment measurement, the moving column unit 6 is held so that it cannot move relative to the base stand 2. A suspension device (suspension unit) 10 equipped with standard wheels 8 is set on the moving column portion 6. In the wheel alignment measuring device according to the present embodiment, in order to clearly understand the relationship between the suspension unit 10 and the wheel alignment, the standard wheel 8 is made of an iron disk that is close to a rigid body.

FIG. 1 and FIG. 2 are schematic views showing a state in which the left front wheel suspension unit 10 of the vehicle is set on the moving column portion 6. The moving column portion 6 includes a support portion 6a for supporting a shock absorber, which is a component of the left front wheel suspension unit 10, a support portion 6b for supporting the upper arm, and a support portion 6c for supporting the lower arm. Are arranged in the same state as the body of the vehicle, and the shock absorber 12, the upper arm 14 and the lower arm 16 are connected to these supporting portions 6a, 6b, 6c, respectively. As a result, the left front wheel suspension unit 10 is supported by the moving column portion 6 in the same state as it is set in the vehicle body. In FIG. 2, 19a is an upper ball joint and 19b is a lower ball joint. An imaginary line passing through the centers of both 19a and 19b is the center line of the king pin. The kingpin center line is the center axis of rotation of the wheel during steering. The right front wheel suspension unit also has the same structure as the left front wheel suspension unit and is supported by the moving column section 6. That is, the moving column portion 6 and the base pedestal 2 correspond to a pedestal that supports the suspension unit instead of the vehicle body.

A worm jack 30 is fixed to the base frame 2 below the suspension unit 10. As shown in FIG. 3, the worm jack 30 is attached to the base stand 2 so that the axis of the lifting rod 32 substantially coincides with the vertical line, and the lifting rod 32 is moved upward or downward (Z (Axial direction). A receiving plate 36 is provided on the upper end of the lifting rod 32, and the receiving plate 36 is in contact with the lower surface of the reference table 22. The reference table 22 is a rectangular plate, and a guide rod 23 projects from the lower surface of the reference table 22 in parallel with the elevating rod 32. The guide rod 23 is slidably inserted into a guide bush 33 fixed to the base frame 2. With this structure, when the worm jack 30 is operated, the reference table 22 is raised and lowered while being held in a horizontal state. A circular turntable receiver 22a is provided at the center of the upper surface of the reference table 22, and a turntable 24 is placed on the turntable receiver 22a in a structure capable of being horizontally displaced. The turntable 24 is a member that performs the same function as the road surface in measuring the wheel alignment, and the standard wheels 8 mounted on the suspension unit 10 are placed on the turntable 24. That is, this turntable 24 corresponds to a movable table.

A horizontal pressing mechanism 40 for applying a pressing force in the horizontal direction to the turntable 24 is provided on the reference table 22. The horizontal pressing mechanism 40 includes a bearing 42 having a female screw formed in a central through hole, and a female screw of the bearing 42 is screwed with a shaft 44 having a male screw. A handle 46 for rotating the shaft 44 around the axis is fixed to one end of the shaft 44, and a load meter 47 is connected to the other end of the shaft 44. Further, a pressing pin 48 is fixed to the end surface 47a of the load meter 47 on the side opposite to the shaft 44, and the tip of the pressing pin 48 is in contact with the side surface 24a of the turntable 24. With this structure, an arbitrary horizontal load can be applied to the turntable 24 by operating the handle 46 so as to extend the shaft 44 toward the turntable 24 side. As shown in FIG. 3, a pair of horizontal pressing mechanisms 40 are installed in the X-axis direction (corresponding to the front-rear direction of the vehicle) and a pair (not shown) in the Y-axis direction (corresponding to the left-right direction of the vehicle). ing.

As shown in FIG. 1, the moving column portion 6 has a measuring device 50 for measuring the Z-axis coordinates of each point of the suspension unit 10 and the standard wheel 8, and an X-axis coordinate measuring device. A measuring device (not shown) and a measuring device (not shown) for measuring the Y-axis coordinate are installed.

Next, a procedure for measuring the wheel alignment under various conditions using the wheel alignment measuring apparatus according to the present embodiment will be described. First, the procedure for measuring the wheel alignment in the bound state and the rebound state of the vehicle will be described. The suspension unit equipped with the standard wheels 8 is set at a predetermined position on the moving column section 6, and when the setting is completed, the worm jack 30 is then operated to set the upper surface of the turntable 24 at a predetermined level. In this state, the four elements of the wheel alignment, namely the toe angle θt, the camber angle θc, the caster angle α and the kingpin tilt angle β are measured.

The toe angle θt is obtained by the following procedure. First, as shown in FIG. 5, X, Y, and Z coordinates of intersections T1 and T2 of the outer circumference of the standard wheel 8 and the horizontal center line are actually measured by a measuring instrument. Next, the distance F in the Y-axis direction between the intersections T1 and T2 is calculated, and the toe angle θt is calculated from the distance F and the diameter D of the standard wheel 8 by the following equation. Toe angle θt = SIN ⁻¹ F / D The camber angle θc is obtained by the following procedure. First, as shown in FIG. 6, X, Y, and Z coordinates of intersections C1 and C2 of the outer periphery of the standard wheel 8 and the vertical center line are measured by a measuring instrument. Next, the distance G in the Y-axis direction between the intersections C1 and C2 is calculated, and the camber angle θc is obtained from the distance G and the diameter D of the standard wheel 8 by the following equation. The camber angle θc = SIN ⁻¹ G / D caster angle α is obtained by the following procedure. First, as shown in FIG. 7, the X, Y, and Z coordinates of the center of the upper ball joint 19a and the center of the lower ball joint 19b are measured with a measuring instrument. Next, the distance H in the Z-axis direction and the distance J in the X-axis direction between the center of the upper ball joint 19a and the center of the lower ball joint 19b are calculated, and these values H, J are substituted into the following equation. To find the caster angle α. The caster angle α = TAN ⁻¹ J / H kingpin inclination angle β is obtained by the following procedure. First, as shown in FIG. 7, X, Y, and Z coordinates of the center of the upper ball joint 19a and the center of the lower ball joint 19b are measured by a measuring instrument. Next, the distance H in the Z-axis direction and the distance K in the Y-axis direction between the center of the upper ball joint 19a and the center of the lower ball joint 19b are calculated, and these values H and K are substituted into the following equation to determine the kingpin tilt angle. Find β. When the kingpin inclination angle β is equal to or less than TAN ^-1 K / H, the level of the turntable 24 is changed by a predetermined amount by the worm jack 30, and the wheel alignment at each level is measured by repeating the above procedure. By this method, wheel alignment can be measured in the bound and rebound states of the vehicle.

When measuring the wheel alignment during acceleration or deceleration of the vehicle, the horizontal pressing mechanism 40 is operated to apply a predetermined horizontal load to the turntable 24 in the X-axis direction (the front-back direction of the vehicle). This is done by adding. The force applied to the turntable 24 is transmitted to the standard wheel 8 via the turntable 24 as if the wheel were to receive a force from the road surface. Therefore, various acceleration or deceleration states of the vehicle can be simulated by arbitrarily changing the horizontal load in the X-axis direction. Further, when the wheel alignment is measured while the vehicle is traveling on a curve, the horizontal pressing mechanism 40 is operated to apply a predetermined horizontal load to the turntable 24 in the X and Y axis directions. Since the suspension unit is set on the movable column section 6, the displacement status of each component can be easily observed.

In the wheel alignment measuring apparatus according to the present embodiment, the pressing force from the horizontal pressing mechanism 40 is applied to the turntable 24 as described above, but this pressing force is applied to the front axle of the wheel. Alternatively, it is also possible to reproduce the running state in a simulated manner by adding from behind (X-axis direction). Further, in the present embodiment, the standard iron wheels 8 are used for the wheels in order to measure the behavior of only the suspension system excluding the deformation of the wheels. However, by using ordinary wheels, the wheels and the suspension unit can be used. It is possible to observe and measure the effect of wheel alignment due to the combined action of and.

[Effect of the device]

 According to the present invention, the wheel alignment measurement accuracy is improved, and the wheel alignment can be detected under various conditions. This makes it easy to understand the factors that change the wheel alignment, and it is possible to take appropriate measures to maintain the wheel alignment at an appropriate value.

[Brief description of drawings]

FIG. 1 is a side view showing a state in which a suspension unit is set on a moving column section.

FIG. 2 is a view taken along the line II-II in FIG.

FIG. 3 is a detailed view of the attachment of the worm jack and the horizontal pressing mechanism.

FIG. 4 is an overall side view of a wheel alignment measuring device.

FIG. 5 is a schematic diagram showing a method of measuring a toe angle θt.

FIG. 6 is a schematic diagram showing a method for measuring a camber angle θc.

FIG. 7 is a schematic diagram showing a method for measuring caster angle α and kingpin inclination angle β.

[Explanation of symbols]

 2 ... Foundation mount (mount) 6 ... Moving column part (mount) 8 ... Standard wheel 10 ... Suspension unit 24 ... Turntable (movable table) 30 ... Worm jack 40 ... Horizontal pressing mechanism

Claims (1)

[Claims for utility model registration] [Claim 1] A pedestal for supporting a suspension device equipped with wheels instead of a vehicle body, and a wheel mounted on the suspension device supported by the pedestal are placed on the pedestal. A movable table capable of relative movement with respect to the movable table, when the movable table is relatively moved with respect to the gantry by a predetermined distance, or under a state in which a predetermined force is applied between the movable table and the gantry, A wheel alignment measuring device, comprising: a measuring mechanism that measures three-dimensional coordinates of a specific point of the wheel and the suspension device.