JPH05288630A - Unbalance value measuring apparatus for wheel of automobile - Google Patents

Abstract

PURPOSE:To enable the making of an inexpensive apparatus using a sensor with a low resolving power by arranging a support roller for sharing the weight of a shaft with a drive roller and a sensor for detecting a load variation rate of a load received with the roller to produce the sensor with a low resolving power. CONSTITUTION:A support roller 25 is mounted on a roller support member 26 facing a drive roller 20 to share the weight of a shaft of an automobile 7A with the roller 20. The roller 25 is pivoted on a member 26 through a bearing 28 mounted askew on a support base movable vertically. A first sensor 29 is fastened on the lower end of the bearing 28 and a second sensor 30 is fastened on the lower end of a bearing 24. Here, the automobile 7A is placed on the rollers 20 and 25 and fixed with a lift device 11. When the roller 20 is rotated with a drive motor 23, a time turns following it and if any unbalance value exists in a rotation system of wheels 12A and 13A, a centrifugal force is generated. The first and second sensors 29 and 30 detect the centrifugal force applied thereon separately and a CPU15 performs an arithmetic processing of the unbalance value. Thus, the arrangement of the roller 25 enables the using of a sensor with a low resolving power.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle wheel unbalance amount measuring apparatus for measuring a centrifugal unbalance amount existing in a wheel rotating system which causes a shake or shimmy generated when a vehicle runs at high speed.

[0002]

2. Description of the Related Art The centrifugal unbalance amount existing in the rotating system of the wheel of an automobile causes stains and shakes that occur during high speed running. Therefore, we are trying to reduce the amount of unbalance by centrifugally balancing the wheels with the tires mounted and the tire mounting parts of the car individually. However, when the wheels are attached, the amount of unbalance is usually increased in the entire rotating system due to the problem of misalignment at the time of attachment and the directionality of the slightly remaining unbalance.

In order to reduce this, it is sufficient to measure the unbalanced amount again with the wheels attached to the vehicle, and a device for measuring the unbalanced amount of the axle system in the state where the vehicle is actually lifted and the wheels idle is commercially available. Has been done.

However, such a commercially available device is practical in terms of lifting a wheel and how the amount of unbalance measured in a completely idle state is related to the occurrence of the above-mentioned stains and shakes. However, it is difficult to use, especially in automobile production lines and large maintenance plants, even though it is highly necessary.

Therefore, in order to solve the above problems, the applicant has previously proposed an embodiment of a vehicle vibration detecting device shown in FIGS. 11 to 13, for example. In this embodiment, the vehicle body load (axial load) is applied to the wheels of the vehicle, and one supporting roller receives all the axial load of one wheel.

[0006] However, when explaining this embodiment in detail, 1 is a pit formed on the floor surface. This pit 1 is provided in an inspection line where vehicle running noise, vibration, engine diagnosis, etc. are performed. Reference numeral 2 denotes a plurality of motor supporting bases respectively installed in the front and rear pits 1, and these motor supporting bases 2 have a required height. Reference numeral 3 denotes a plurality of drive motors provided on the upper surface of each motor support base 2.

Reference numeral 4 denotes a plurality of sensor support bases installed separately from the motor support base 2 in the pit 1. The sensor support bases 4 are lower than the motor support bases.

Reference numeral 5 is sandwiched between the sensor support base 4 and the roller support plate 6 provided above the sensor support base, and detects vibration of the vehicle 7. A plurality of vibration detection members. These vibration detecting members 5 are plate-shaped members having a plurality of sensors at the corners of the upper surface, etc., and are appropriately integrally attached to the sensor support bases 4 and the roller support plates 6.

Numeral 8 is provided on the upper surface of the roller support plate 6 via bearings 9, respectively, and is rotated by a driving force of each driving motor 3 via a power transmission means 10 such as a belt or a chain and holding means. A plurality of vibration transmission rollers for rotating a front wheel 12 and a rear wheel 13 of the vehicle 7 fixedly held by 11. As the holding means 11, in this embodiment, two lift devices appropriately buried in the floor surface F are used. These lift devices 11
A support portion 11b that engages with the underfloor of the vehicle 7 is provided at the tip of the operating rod 11a.

Reference numeral 14 is a pit cover plate, 15 is a central processing unit that is electrically connected to the vibration detecting member 5 and has operation buttons, a control panel, etc., and 16 is an electrical connection with the central processing unit 15. A television-type display device connected to
Reference numeral 17 denotes a sheet-shaped or block-shaped vibration-damping member that is laid on the inner wall surface of each pit 1 so as not to be affected by vibrations generated from other peripheral devices.

In the above structure, first, the vehicle 7 is placed on the floor F.
While traveling on, get on the front and rear vibration transmission rollers 8. Next, when the front wheels 12 and the rear wheels 13 of the vehicle 7 ride on the respective vibration transmission rollers 8, the vehicle body is held by the holding means 11 so that the vehicle body does not move.

After that, each drive motor 3 is started.
In this case, the drive motors 3 can be driven simultaneously or individually. When the drive motor 3 is driven, the driving force is transmitted to each vibration transmission roller 8 via the power transmission means 10. Front wheel 1 of vehicle 7
2 and the rear wheel 13 are independently rotated by the rotation of each vibration transmission roller 8, but the rotational force is gradually increased,
For example, when traveling on a general highway at 120 km / h, a state close to actual traveling is reproduced.

Thus, the front wheels 12 and / or the rear wheels 1
Abnormal vibrations generated while 3 is rotating at a constant speed or acceleration / deceleration pass through the respective vibration transmission rollers 8 and the respective vibration detection members 5
Is transmitted to each. Then, the vibration of the front wheels 12 and / or the rear wheels 13 detected by each vibration detection member 5 is sent to the central processing unit 15 as a vibration signal (frequency), and the shake or shimmy of the vehicle can be analyzed or analyzed. Become. The data processed by the central processing unit 15 is displayed on the display unit 16.

However, the above-mentioned embodiment has the following problems. That is, in general, a sensor for measuring centrifugal force is applied with vehicle gravity (Wc) applied to an axle and gravity (Ws) of a measuring device, and centrifugal force (f) is applied on the sensor, so that high resolution is required. Then, it is mathematically known that this resolution is obtained by the following Equation 1.

[0015]

[Equation 1]

The problem here depends on the type of car, but in the above embodiment, for example, Wc is 300 to 500 kg,
While Ws is around 100 kg, f is 100 to 2
Since it is about 00N, the sensor measures the amount of change of 2 to 5% of the total amount, which makes the signal handling extremely difficult.

Generally, a sensor or a measuring instrument has a fixed minimum measuring unit for the entire measuring width. The price of will increase significantly. In the case of a sensor, the so-called resolution is increased, or the signal-to-noise ratio (SN ratio) is deteriorated, which is disadvantageous in that it becomes expensive in any case.

[0018]

SUMMARY OF THE INVENTION The present invention, in view of the above-mentioned conventional drawbacks and the problems of the above-mentioned embodiment of the prior application, can obtain a high resolution even when the same sensor is used.
Since the detected signal is easy to handle, it is possible to use an inexpensive sensor, so that the device can be finally manufactured at low cost, and the device can be clean without being affected by noise generated from the driving device. An object of the present invention is to obtain an unbalanced amount measuring device for a vehicle wheel, which can obtain a waveform and can be easily installed in a production line of a factory or an automobile maintenance shop.

[0019]

SUMMARY OF THE INVENTION A vehicle wheel unbalance amount measuring apparatus according to the present invention receives a vehicle axle load through a wheel and rotates the wheel by a driving force of a driving motor. And a support roller attached to the roller support member so as to face the drive roller and also carrying the axle load of the vehicle together with the drive roller via the wheels. And a sensor mounted on the roller support member so as to detect the load variation rate of the load received by the support roller.

[0020]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

In the description of each embodiment of the present invention, the same parts as those of the above-mentioned embodiment of the prior application will be denoted by the same or similar reference numerals and overlapping description will be omitted.

First, in the embodiment shown in FIGS. 1 to 7, reference numeral 20 is a vehicle 7A through wheels 12A and 13A.
Axle load (means the weight of the car added to one tire)
A drive roller that receives Wc and rotates the wheels 12A and 13A simultaneously or individually by the drive force of a drive motor 23 installed on the upper surface of a support base 22 that forms a part of the support member 21. Is. The drive roller 20 is pivotally attached to the support member 21 via a bearing 24 which constitutes a part of the support member 21, as shown in FIG. The bearing 24
Is fitted in an insertion hole formed in the support base 22 so as to be vertically movable.

Numeral 25 is attached to a roller supporting member 26 so as to face the driving roller 20, and also the axle weight Wc of the automobile is driven together with the driving roller 20 through the wheels 12A and 13A. It is a supporting roller to bear. This support roller 25 is also a roller support member 26 as shown in FIG.
Is rotatably attached to the roller support member 26 through a support base 27 that constitutes the above and a bearing 28 that is obliquely attached to the support base 27.

Reference numeral 29 is a first sensor fixedly attached to the lower end of the bearing 28 of the roller support member 26 so that the load fluctuation rate of the load received by the support roller 25 can be detected. -Is. The bearing 28 is also fitted in an insertion hole formed in the support 27 so as to be vertically movable.

On the other hand, 30 is a second sensor fixedly attached to the lower end of the bearing 24 of the support member 21 so as to detect the load fluctuation rate of the load received by the drive roller 20. is there. The second sensor 30 is not always an essential requirement of this embodiment, but when the second sensor is provided, the first and second sensors 29, 30 are provided.
Combining the measured values detected by the method has the advantage of facilitating waveform shaping and thus facilitating the discrimination between vibration and noise.

Incidentally, the first and second sensors 29, 3
0 is preferably mounted on the lower end portions of the bearings 24 and 28 so that no extra force other than centrifugal force such as inertial force associated with the motion of each roller acts, but it is preferable that the bearing of the embodiment of the previous application is used. As described above, it may be sandwiched between the upper support and the lower support. Support roller 25 and drive roller 2
0 may be installed only on the front wheels of the vehicle 7A.

In the above structure, when the vehicle 7A is mounted on the drive roller 20 and the support roller 25 and fixed by the lift device 11, both rollers 20 and 25 are fixed. Axial load Wc of the automobile 7A (wheels 12A, 13A) is added to.

Then, when the drive motor 23 is started and the drive roller 20 rotates, the tire follows and rotates, and there is an unbalanced amount in the rotating system of the wheels 12A and 13A including the tire. And a centrifugal force f is generated. When the centrifugal force f is generated here, a load is applied in the centrifugal direction, so that the wheel 12
In addition to the load up to that point, centrifugal force is also applied to the parts that support A and 13A. Therefore, the first and second sensors 29, 30 detect and measure the applied centrifugal force f, respectively.

However, since the centrifugal force f is in the minus direction when it is applied to the opposite side of the measuring section, the change in the load generated by one rotation of the wheel becomes a sine curve. In the sine curve, the magnitude of the centrifugal force is proportional to the peak value of the curve, so the unbalance amount of the rotating system can be measured. The resolution at this time is shown in the schematic diagram of FIG. Formula 2 is obtained, and Wc ′ is half of Wc.

[0030]

[Equation 2]

In this embodiment, the driving roller-2
0 and the support roller 25 are provided so as to face each other on the left and right, but as shown in FIGS. 8 to 10, the drive roller 20B is arranged near the center of the wheels 12B and 13B. On the other hand, the support roller 25B may be arranged at a desired angle apart from the drive roller 20B in the horizontal direction of the wheel. As shown in the schematic diagram of FIG. 9 and the above-described mathematical expression 2, the resolution at this time depends on how α and β are selected.
It is less than half of c. Further, in this embodiment, instead of the fixed lift, a fixing tool 40 for fixing the wheels is used.

[0032]

As is apparent from the above description, when the concept of the invention, the measured values and the like of the embodiment of the prior application and the embodiment of the present invention are compared, the results are shown in Table 1 below. Therefore, since the present invention can use a low-resolution sensor (inexpensive sensor), an inexpensive device can be finally manufactured.

[0033]

[Table 1]

[Brief description of drawings]

[Figure 1]

FIG. 3 is an explanatory diagram showing an embodiment of the present invention.

FIG. 4 and

FIG. 5 is an explanatory diagram showing a main part of the present invention.

FIG. 6 and

FIG. 7 is an explanatory diagram for explaining the basic concept of the present invention.

FIG. 8

FIG. 10 is an explanatory diagram for explaining another embodiment of the present invention.

FIG. 10

FIG. 13 is an explanatory diagram showing an example of a prior application.

[Explanation of symbols]

 20, 20B ... Driving roller, 12A, 12B, 13A, 13B ... Wheel, 7A ... Automotive, 21 ... Supporting member, 22, 27 ... Supporting base, 23 ... Drive motor, 24, 28 ... Bearing, 25, 25B ... Supporting roller , 26 ... Roller support member, 29 ... First sensor, 30 ... Second sensor.

Claims (3)

[Claims] 1. A drive roller which receives an axle load of an automobile through a wheel and rotates the wheel by a drive force of a drive motor.
And a support roller attached to the roller support member so as to face the drive roller and also carrying the axle load of the vehicle together with the drive roller via the wheels. An unbalanced amount measuring device for an automobile wheel, comprising: a sensor mounted on the roller supporting member so as to detect a load variation rate of a load received by the supporting roller. 2. The drive roller according to claim 1, wherein the drive roller is disposed directly below the center of the wheel, while the support roller is horizontal from the drive roller to a desired angle. An apparatus for measuring an unbalanced amount of a vehicle wheel, characterized in that they are arranged apart from each other. 3. The drive roller supporting member according to claim 1, further comprising a second sensor for detecting a load variation rate of a load received by the drive roller. Measuring device for unbalance of automobile wheels.