JPH09159426A - Wheel alignment measuring apparatus for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a wheel alignment measuring apparatus for vehicle which is insusceptible to fluctuation in the angle of each shaft of wheel and can be fixed easily without causing any trouble at the time of measurement by a structure wherein a laser displacement sensor is not susceptible to fluctuation in the angle of wheel and a reflector, a rotational angle sensor and a servo motor do not rotate together with the wheel. SOLUTION: The wheel alignment measuring apparatus for vehicle comprises a wheel side measuring apparatus including reflectors 11X1 , 11X2 , 11Y, 11Z fixed to the wheel side of a vehicle V to be measured, a servo motor 9, and an angle sensor 10, and a platform side measuring apparatus fixed to the platform side of a basic characteristics measuring apparatus for vehicle including laser displacement sensors 12X1 , 12X2 , 12Y, 12Z. Since the sensor 12 is secured to the platform side, it is not susceptible to vibration of wheel and since the reflector 11, the sensor 10 and the motor 9 are fixed to the wheel through a bearing 3, they do not rotate together with the wheel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle wheel alignment measuring device, and more particularly to a vehicle wheel alignment measuring device suitable for being used by incorporating it into a vehicle basic characteristic measuring device.

[0002]

2. Description of the Related Art A vehicle basic characteristic measuring apparatus is known as a test apparatus for measuring basic static characteristics such as suspension and steering of a vehicle in a test room. With this device, the body of the test vehicle is fixed to the ground, and the rotation, left, right, up, and down forces are applied to the wheels, and the relationship with the reaction force generated at that time is processed to perform various measurements. It can be carried out.

This vehicle basic characteristic measuring device is provided with a wheel alignment measuring device for measuring a caster angle, a camber angle, a toe angle and the like. Conventionally, as this wheel alignment measuring device, a device that mechanically connects a measuring device fixed on a platform to the wheel and mechanically detects the movement of the wheel is used.However, a mechanical wheel alignment measuring device is used. However, there is a problem that measurement cannot follow in a high-speed test due to deterioration of measurement accuracy due to friction of a movable part and restriction of mass, so the above problem is solved by using a non-contact distance sensor or the like. A wheel alignment measuring device configured as described above has also been proposed.

FIG. 4 is a perspective view showing a conventional wheel alignment measuring apparatus for a non-contact vehicle disclosed in Japanese Patent Publication No. 6-25662. This wheel alignment measuring device puts each vehicle wheel on the platform table independently, and applies vertical, lateral, front-rear direction, and rotational load to each wheel independently to determine the basic characteristics of vehicle suspension and steering. It is incorporated in a vehicle basic characteristic measuring device that measures

The wheel alignment measuring device comprises a platform side sensor unit A mounted on the platform side and a wheel side sensor unit B mounted on the wheel side.

On the platform side sensor unit A,
Toe angle sensors A22a and A22b, X reflector A23,
A Y reflector A19 and a Z reflector A20 are provided.

On the other hand, the wheel side sensor unit is provided with reflectors B4a and B4b for reflecting the light from the toe angle sensors A22a and A22b, respectively, and the toe angle sensors A22a and A22b are fired by themselves and reflected by the reflectors. By receiving the light reflected by B4a and B4b, the distance between the corresponding reflectors B4a and B4b is respectively measured, and the measured distance is calculated by calculating the rotation angle about the Z axis, that is, the toe angle. Used for.

Further, the wheel side sensor unit B includes
An X-axis sensor B5, a Y-axis sensor B6, and a Z-axis sensor B7 are provided, and the X-axis sensor B5 fires by itself and the X-axis reflector A
The Y-axis sensor B6 emits the light reflected by 23 and the light reflected by the Y-reflector A19, and the Z-axis sensor B7 emits the light emitted by itself and reflected by the Z-reflector A20. Each of them is received and the distance to the corresponding reflector is detected.

Further, in the wheel side sensor unit B, the caster angle sensor B is provided adjacent to the sensors B5 to B7.
8 and a camber angle sensor B9 are provided respectively, and the caster angle sensor B8 measures the rotation angle about the Y axis, that is, the caster angle, and the camber angle sensor B9 measures the rotation angle about the X axis, that is, the camber angle. Used to

Each of the laser displacement sensors is
It has a laser element which emits a laser beam to a corresponding reflecting plate, and an optical position detecting element which receives the laser beam reflected from the reflecting plate and detects the distance to the reflecting plate.

In the vehicle wheel alignment measuring device having the above structure, the true distances on the X, Y and Z planes can be obtained by knowing each measured value and the angle of each component. The angle of each component can be obtained from the difference in distance between the caster angle and the camper angle measured by the tilt angle sensor and the toe angle measured by the left and right two laser displacement sensors A22a and A22b. An appropriate measurement result can be obtained by considering the change in the distance between each of the reflection plates A23, A19, A20 and the corresponding laser displacement sensor B5, B6, B7.

[0012]

However, in the vehicle wheel alignment measuring device using the above-mentioned conventional non-contact distance sensor, etc., in the laser displacement meter, the laser incident angle is perpendicular to the surface on which the laser light is reflected. Is preferable, and the factor that causes a measurement error increases as the incident angle deviates from a right angle. Therefore, in order to obtain a highly accurate measurement value, it is necessary to keep the incident angle as right angle as possible. Since the laser displacement sensor and the inclination angle sensor are provided as the wheel side sensor unit in the sensor mounting part directly connected to the wheel, it is difficult to mount the sensor and its wiring, and these interfere with the measurement. The wheel alignment measuring device may be damaged due to the influence of wheel vibration or the like.

Therefore, the present invention has been made in view of the above-mentioned problems in the conventional wheel alignment measuring device for a vehicle, in which the laser displacement sensor is not affected by the change angle of the wheel and is reflected. Since the plate, rotation angle sensor, and servo motor do not rotate with the wheel, the installation work is easy, and it does not interfere with the measurement and is not affected by changes in each axis angle of the wheel. An object is to provide an alignment measuring device.

[0014]

According to the first aspect of the present invention,
A vehicle in which each wheel of the vehicle under test is placed on the platform table independently, and vertical, horizontal, front-back, and rotational loads are applied to each wheel independently to measure the basic static characteristics of the vehicle suspension and steering. A wheel alignment measuring device for a vehicle, which is incorporated in a basic characteristic measuring device and measures the state of each wheel, wherein a main shaft extended to a wheel of the vehicle under test, a bearing attached to the main shaft, and A pair of first pins, which are provided upright on the outer ring of the bearing in a direction perpendicular and horizontal to the axis of the main shaft and in mutually opposite directions, and rotatably provided on the pair of first pins so as to surround the main shaft. A fixed inner gimbal, a weight fixed to a lower surface of the inner gimbal, and having a mass larger than a mass of the inner gimbal above the first pin; A pair of second pins standing upright in opposite directions in a direction perpendicular to the axis of the main shaft and the axis of the first pin, and rotatably around the pair of second pins so as to surround the inner gimbal. An outer gimbal provided on the outer gimbal, a pair of X-reflecting plates for toe angle measurement arranged on the outer gimbal in front of and behind the vehicle with the main shaft interposed therebetween, and for a camper angle measurement attached to the outer gimbal. Fixed to the Y-reflector and Z-reflector for caster angle measurement and the platform of the vehicle basic characteristic measuring device, and emits a laser beam to each of the Y-reflector and the Z-reflector. The Y-axis sensor and the Z-axis sensor for measuring the reflection angle of the laser light as the camper angle and the caster angle by receiving the laser light, and the vehicle basic characteristic measuring device described above. A pair of Xs fixed to the platform for emitting a laser beam to each of the pair of X reflectors and receiving the laser beam from each of the X reflectors to measure the distance to each of the X reflectors. The axis sensor and the second pin are rotated to keep the distances between the pair of X-reflecting plates and the pair of X-axis sensors constant, and the laser light from the X-axis sensor is coupled to the pair of X-axis sensors. Of the X reflection plate, and a rotation angle sensor for measuring the rotation angle of the second pin by the servo motor as a toe angle. And

According to the first aspect of the invention, since the laser displacement sensor is fixed to the platform side,
It is not affected by wheel vibration. Further, since the reflector, the rotation angle sensor and the servo motor are attached to the wheel via the bearing, they do not rotate together with the wheel. Also, the laser beam always keeps a right angle to the reflector.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a specific example of an embodiment of a vehicle wheel alignment measuring apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a vehicle wheel alignment measuring device according to the present invention. This wheel alignment measuring device 1
Broadly speaking, reflector 11X ₁ which is attached to the wheel side of the measured vehicle V, 11X _2, 11Y, 11Z, and the wheel-side measuring device such as a servo motor 9 and the angle sensor 10, the platform side of the vehicle basic characteristic measuring device Laser type displacement sensors 12X ₁ , 12X ₂ , 12 attached to
It consists of a platform side measuring device consisting of Y, 12Z, etc.

As the vehicle basic characteristic measuring device, a force applying device as shown in FIG. 1 is used. This force device
A bearing frame 24 fixed to the upper end of an elevating shaft guided up and down by a guide (not shown) has a platform 23 having an intermediate portion swingably supported on the left and right, and the platform 23 has a vertical movement (not shown). A frame, a front-back moving frame 18, and a left-right moving frame 19 are provided,
The vertical moving frame is provided by a vertical actuator (not shown), and the front and rear moving frame 18 and the left and right moving frame 19 are respectively provided with front and rear actuators 21 and left and right actuators 22 to drive the respective frames in a predetermined direction.

The front-rear moving frame 18 is provided with a rotary table 20 which is rotatably supported by a hydrostatic bearing or the like. The rotary table 20 is hydraulically controlled by a servo valve (not shown) and driven in the rotational direction. A rotary actuator is connected. And this rotary table 20
The wheel T is placed on the top.

Next, the wheel side measuring device of the vehicle wheel alignment measuring device 1 according to the present invention will be described. As shown in FIG. 1, the spindle 2 is provided on the wheel side so as to extend to the wheels T of the vehicle under test V. This spindle 2
Is rotatably supported by a bearing 3, and its end 2a is
Has two chamfers for fixing a camber angle measuring angle sensor 10Y, a caster angle measuring angle sensor, and the like, which will be described later.

FIG. 2 is a schematic view of the wheel side measuring device. As shown in this figure, a pair of first pins 4 is provided upright on the outer ring of the bearing 3 in a direction vertical and horizontal to the axis of the main shaft 2. The first pin 4 penetrates the side surface 5c of the inner gimbal 5 arranged so as to cover the main shaft 2, and rotatably supports the inner gimbal 5.

On the lower surface 5b of the inner gimbal 5, the mass of the inner gimbal 5 above the first pin 4 is larger so that the reflecting surfaces of the X-axis reflectors 11X ₁ and 11X ₂ are always vertical. A weight 7 having a mass is attached.
Further, on the upper surface 5a and the lower surface 5b of the inner gimbal 5, second pins 6 are provided upright in a direction perpendicular to these surfaces and in the vertical direction. Each of the second pins 6 penetrates the upper surface 8a and the lower surface 8b of the outer gimbal 8 arranged so as to surround the inner gimbal, and supports the inner gimbal 5 rotatably around the second pins 6. There is. In addition, the lower second pin 6
Is connected to the output shaft of the servomotor 9, and the toe angle measuring angle sensor 10X is attached to the servomotor 9.

The upper surface 8a and the right side surface 8c of the outer gimbal 8
Are the Z-axis reflector 11Z and the caster angle measurement, respectively.
And 11Y for measuring the camper angle are fixed. Also,
For the toe angle measurement on the left and right side portions 8d of the outer gimbal 8.
Pair of X-axis reflectors 11X1 _,11X_TwoIs attached
You.

On the other hand, on the platform 23 side of the vehicle basic characteristic measuring device, each of the reflection plates 11X ₁ , 11X ₂ ,
Laser type displacement sensors 12X ₁ , 12X ₂ , 12Y, 12Z for measuring the reflection angle of the laser light by emitting the laser light to 11Y, 11Z and receiving the laser light reflected by each reflector. It is attached. That is, the Z-axis sensor 12 is attached to the Z-axis reflector 11Z.
Z, Y axis is the reflection plate 11Y Y-axis sensor 12Y, the first 1X axis reflector 11X ₁ second 1X axis sensor 12X _1, the first 2X axis reflector 11X ₂ is disposed a 1X axis sensor 12X _2.
This laser type displacement sensor 12X ₁ , 12X ₂ , 12Y,
12Z is similar to the sensor disclosed in Japanese Patent Publication No. 6-25662, and detailed description thereof will be omitted.

Next, the operation of the wheel alignment measuring device 1 having the above structure will be described. The inner gimbal 5 is attached to the main shaft 2 via a bearing 3, and
Since the weight 7 is fixed to the lower surface 5a of the inner gimbal 5, even if the main shaft 2 rotates, the weight 7 fixed to the inner gimbal 5 always faces vertically downward. Further, the outer ring of the bearing 3 has a vertical and horizontal direction with respect to the axis of the main shaft 2.
Since a pair of first pins 4 are erected in opposite directions and the inner gimbal 5 is rotatable by the first pins 4, the longitudinal section of the inner gimbal 5 is always perpendicular to the main shaft 2. To maintain.

Under the above condition, the first X-axis reflector 11X ₁
When the first 1X axis distance X1 between the sensor 12X _1, and the 2X axis reflector 11X ₂ the displacement distance X ₂ between the 2X axis sensor 12X ₂ was measured, the servo such that the difference of X ₁ and X ₂ is eliminated The motor 9 is rotationally driven, and the vertical cross section of the outer gimbal 8 is always maintained in a vertical relationship with the main shaft 2.

In this state, the load is applied to the wheels T of the vehicle V to be tested placed on the table 20 of the platform 23 independently in the vertical direction, the horizontal direction, the front-back direction, the rotational direction, and the like by the vehicle basic characteristic measuring device. , When the inclination of the wheel T is changed or the main shaft 2 is displaced, the Y reflector 11
The Y-axis sensor 12 is attached to each of the Y and Z reflectors 11Z.
Laser light is emitted from the Y and Z axis sensors 12Z, and the laser light from each of the reflection plates 11Y and 11Z is emitted from the Y axis sensor 12.
When received by the Y and Z axis sensors 12Z, the reflection angle of the laser light can be measured as a camper angle and a caster angle, respectively.

Laser beams are emitted from the X-axis sensors 12X ₁ and 12X ₂ to the pair of X reflectors 11X ₁ and 11X ₂ , respectively, and the laser beams from the pair of reflectors 11X ₁ and 11X ₂ are emitted. The distance to each X reflection plate is measured by receiving by the X-axis sensors 12X ₁ and 12X ₂ .
One of the second pins 6 is rotated by the servo motor 9,
Respectively of the pair of X reflector 11X _1, 11X _2, while maintaining the distance X _1, X ₂ and each X-axis sensor 12X _1, 12X ₂ constant, the X-axis sensor 12X _1, 12X ₂
The laser light from the pair of X reflectors 11X ₁ and 11
The rotation angle of the second pin 6 can be measured as a toe angle by the toe angle measuring angle sensor 10X by making the light incident on the reflecting surface of X _{2 at} a right angle. However, since control of the reflecting surfaces of the X reflectors 11X ₁ and 11X ₂ by the servomotor 9 causes a delay, a highly accurate measurement value cannot be obtained only by the toe angle measurement value by the toe angle measurement angle sensor 10X. In order to improve the measurement accuracy, it is necessary to correct the measured toe angle value by changing the distances X ₁ and X ₂ .

In the vehicle wheel alignment measuring device having the above structure, the inclination of the tire T becomes large, and the inclination of the main shaft 2 and the reflection plate 11X ₁ ,
It is conceivable that any one of 11X ₂ , 11Y, and 11Z or a plurality of tilts becomes large, and the laser beams from the corresponding laser displacement sensors 12X ₁ , 12X ₂ , 12Y, and 12Z do not return. In such a case, the camber angle measuring angle sensor 10Y and the caster angle measuring angle sensor 1 are attached to the two chamfered ends 2a of the main shaft 2.
Install 0Z.

Then, the laser type displacement sensors 12Y and 12Z arranged on the platform side are rotationally driven to enable reception of laser light, and the angles measured by these laser type displacement sensors 12Y and 12Z and the camper angle measurement. The camper angle and the caster angle can be measured by combining the angles measured by the working angle sensor 10Y and the caster angle measuring angle sensor 10Z.

The main shaft 2 has a camper angle measuring angle sensor 10Y and a caster angle measuring angle sensor 1 attached thereto.
The balance weights 13Y and 13Z are attached in order to eliminate the influence of the weight of 0Z on the measurement angle. The camper angle measuring angle sensor 10Y, the caster angle measuring angle sensor 10Z, and the balance weights 13Y and 13Z are attached to the main shaft 2 via an inclinometer clamp. Also,
In order to eliminate the influence of the increase in the load on the wheel T side, in addition to the weight 7 fixed to the lower surface 5a of the inner gimbal 5, the weight 1
5 is attached.

[0031]

According to the invention described in claim 1, the laser displacement sensor is not affected by the vibration of the wheel, and the reflector and the servomotor with the rotation angle sensor are
Since it does not rotate with the wheel, it is possible to provide a wheel alignment measuring device for a vehicle, which is easy to install and does not interfere with the measurement and is not affected by the vibration of the wheel.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a vehicle wheel alignment measuring device according to the present invention.

FIG. 2 is a schematic diagram for explaining a wheel side sensor unit according to the present invention.

FIG. 3 is a perspective view showing another embodiment of the vehicle wheel alignment measuring device according to the present invention.

FIG. 4 is a perspective view showing a conventional vehicle wheel alignment measuring device.

[Explanation of symbols]

 1 Vehicle Wheel Alignment Measuring Device 2 Spindle 3 Bearing 4 First Pin 5 Inner Gimbal 6 Second Pin 7, 15 Weight 8 Outer Gimbal 9 Servo Motor 10 Angle Sensor 11 Reflector 12 Laser Displacement Sensor 13 Balance Weight 14 Inclinometer Clamp 19 Left-right movement frame 20 Rotary movement table 22 Left-right actuator 23 Platform 24 Bearing frame

Claims (1)

[Claims] 1. Wheels of a vehicle under test are placed on a platform table independently, and vertical, horizontal, front-rear, and rotational loads are independently applied to the wheels to provide basic static control for suspension and steering of the vehicle. A wheel alignment measuring device for a vehicle, which is incorporated in a vehicle basic characteristic measuring device for measuring characteristics and measures the state of each wheel, comprising a main shaft extending from the wheel of the vehicle under test, and a main shaft attached to the main shaft. Bearings, a pair of first pins provided on the outer ring of the bearings in a direction vertical and horizontal to the axis of the main shaft and in opposite directions, and rotatably on the pair of first pins. An inner gimbal provided so as to surround the inner gimbal, a weight fixed to a lower surface of the inner gimbal, and having a mass larger than a mass of the inner gimbal above the first pin; A pair of second pins erected on the side gimbals in a direction perpendicular to the axis of the main shaft and an axis of the first pin in opposite directions, and rotatable about the pair of second pins; An outer gimbal provided so as to surround the inner gimbal, a pair of X-reflecting plates for toe angle measurement arranged on the outer gimbal in front of and behind the vehicle with the main shaft interposed therebetween, and attached to the outer gimbal. A Y-reflector for measuring the camper angle and a Z-reflector for measuring the caster angle, fixed to the platform of the vehicle basic characteristic measuring device, and emitting a laser beam to each of the Y-reflector and the Z-reflector, A Y-axis sensor and a Z-axis sensor for measuring the reflection angle of the laser light as a camper angle and a caster angle by receiving the laser light from each of the reflectors; Fixed to the platform of the characteristic measuring device, for emitting a laser beam to each of the pair of X reflectors, and receiving the laser beam from each of the reflectors to measure the distance to each X reflector. A pair of X
The axis sensor and the second pin are rotated to keep the distances between the pair of X-reflecting plates and the pair of X-axis sensors constant, and the laser light from the X-axis sensor is coupled to the pair of X-axis sensors. And a rotation angle sensor for measuring the rotation angle of the second pin by the servo motor as a toe angle. And vehicle wheel alignment measuring device.