JPH08136407A - Gear sound inspection device - Google Patents

Abstract

(57) [Summary] [Purpose] When inspecting a vehicle differential gear for inaccuracies such as poor precision and tooth dents, it should be possible to perform inspections in a state close to actual driving. [Structure] The differential case W is clamped by a clamper 6 of a clamp base 3, a load is applied to a gear mechanism inside the case W by a torque load / detection device 5, and a motor 4 is driven to input a gear mechanism by an input shaft 11. To rotate.
Then, at this time, the vibration generated by the gear mechanism is measured by the vibration sensor 8 provided in the clamper 6, and the noise value is obtained from the correlation between the vibration and the noise value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved apparatus for inspecting the meshing of a differential gear of a vehicle.

[0002]

2. Description of the Related Art If a gear incorporated in a differential case of a vehicle has a poor accuracy or a dent on a tooth surface, noise may be generated when the vehicle is running, resulting in poor riding comfort. Therefore, for example, Japanese Utility Model Laid-Open No. 5-62841 proposes a device that detects a vibration or a sound generated when a gear mechanism of a differential device is operated and inspects a defect from the vibration or the sound.

[0003]

However, in the above-mentioned device, the inspection is carried out in the middle of the assembly line of the differential device, and at that time, the gear mechanism is simply rotated by the work driver, and the vibration generated at that time is generated. Since it is detected by the vibration sensor, it is not possible to accurately inspect for abnormal noise under load on the gear mechanism, such as during actual traveling.

[0004]

In order to solve the above-mentioned problems, the present invention relates to a rotary drive means for rotationally driving a gear mechanism incorporated in a differential case at an arbitrary rotational speed, and a predetermined gear mechanism for the gear mechanism at the time of this rotary drive. The load means for applying the load and the vibration detecting means for detecting the vibration generated in the gear mechanism during rotation are provided. Then, a clamper for positioning and fixing the differential case is provided, and the vibration sensor of the vibration detecting means is incorporated in this clamper.

[0005]

The magnitude of vibration and the magnitude of sound have a certain correlation, and the magnitude of noise can be inspected almost accurately by detecting the magnitude of vibration. Therefore, if the gear mechanism is rotationally driven in a state where a load is applied to the gear mechanism and the vibration at that time is detected by the vibration detecting means, the noise during actual traveling can be accurately known. In addition, by incorporating the vibration sensor of the vibration detection means into the clamper, the measurement location becomes the same position each time, and the variation in measurement accuracy can be reduced.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is an overall view of the gear sound inspection device, FIG. 2 is an enlarged vertical cross-sectional view of a main part, and FIG. 3 is a bottom view seen from the direction AA of FIG. As shown in FIG. 1, the gear sound inspection device of the present invention includes a work table 1 on which a differential case W assembled with a gear mechanism is placed, and the work table 1
Clamp table 3 which is provided above and which can be moved up and down by an elevating cylinder 2, a motor 4 as a rotation driving means capable of transmitting a rotation driving force to a drive shaft Ws extending laterally from the differential case W, and a differential case W. A torque load / detection device 5 is provided as a load means capable of applying a load to a part of the internal gear mechanism.

A gear mechanism including a ring gear Wr as shown in FIG. 2 is constructed inside the differential case W (other gears are omitted in the figure), and a shaft insertion hole at the center of the ring gear Wr. Splines are formed in h. The ring gear Wr meshes with the bevel gear Wa at the tip of the drive shaft Ws, and a spline fitting portion s is formed at the protruding tip of the drive shaft Ws. Then, in this device, the meshing state of the bevel gear Wa and the ring gear Wr,
In addition, the meshing condition of the gear mechanism and its downstream is collectively checked.

The clamp base 3 is provided with three clampers 6 as shown in FIGS. 2 and 3 (only one clamper is shown in FIG. 2), and the clamper 3 is hung downward from the clamp base 3. The clamper 6 is provided at its tip end with a fitting part 6a which can be fitted into a recess provided in, for example, the peripheral portion of the differential case W, and the fitting part 6a is provided by a spring 7 at the base end. It is supported in a floating state. Further, among the plurality of clampers 6, one portion (bevel gear Wa
A vibration sensor 8 is provided in the clamper 6 (in the vicinity of the meshing portion of the ring gear Wr).

Further, as shown in FIG. 1, an input shaft 11 is connected to an output shaft 4a of the motor 4 via a coupling 10, and the tip of the input shaft 11 is made movable back and forth. The drive shaft Ws includes a spline portion 11a that can be fitted to the spline fitting portion s. Then, if the tip end of the input shaft 11 is moved forward to be fitted into the spline fitting portion s of the drive shaft Ws, the rotational driving force of the motor 4 can be transmitted, and it is moved backward and input from the spline fitting portion s. Spline part 1 of shaft 11
The transmission of the rotational driving force is cut off by pulling out 1a.

The torque load / detection device 5 is attached to the bracket 12 via a plate 13 and has a spline shaft 14a which can be inserted into the shaft insertion hole h of the ring gear Wr in the differential case W. 14 and a brake unit 17 that is connected to the torque detection unit 14 via a plurality of couplings 15 and 16 and that can apply an arbitrary load torque. Then, the spline shaft 14a of the torque detection unit 14 is inserted into the shaft insertion hole h of the ring gear Wr for spline fitting, and the brake torque is applied by the brake unit 17 to apply a load to the gear mechanism in the differential case W. The load applied by the brake unit 17 may be, for example, friction or a known means such as electromagnetic induction. Further, the torque detector 14 can detect the load torque.

Next, a vibration (G) is generated based on FIGS. 4 and 5.
And the noise value (dB) will be described. Here, FIG. 4 is an example of the correlation of the front side differential and FIG. 5 is an example of the rear side differential, and the vertical axis represents the noise value (dB) and the horizontal axis represents the vibration (G), respectively. Then, measure vibration and noise values from many test models,
By connecting the average values, a curve as shown in the figure is drawn, and it can be seen that the vibration and the noise value have a mutual correlation.

Next, the outline of the operation of the gear sound inspection apparatus and the operational effects will be described. First, the differential case W is positioned on the work table 1, the lift cylinder 2 on the upper side is operated, the clamp table 3 is lowered from above, and the differential case W is positioned and fixed by each clamper 6. At this time, the spline shaft 14a of the torque detector 14 is spline-fitted into the shaft insertion hole h of the ring gear Wr. At the same time, the input shaft 11 is advanced so that the spline portion 11a at the tip end is fitted to the spline fitting portion s of the drive shaft Ws.

Next, the motor 4 is driven to transmit the rotational force from the drive shaft Ws to the gear mechanism, and at the same time, the torque load / detection device 5 applies a torque load to the gear mechanism. Then, this torque load is set to a value that is substantially the same as the load received during actual traveling, and the vibration generated in the gear mechanism at that time is measured by the vibration sensor 8. Then, if this vibration is converted into a noise value according to FIG. 4 or FIG. 5, noise in a state close to actual traveling can be measured almost accurately. In addition, at this time, since the vibration sensor 8 is built in the clamper 6, the measurement position is the same each time, and there is little variation in measurement accuracy. Then, for example, when the vibration value exceeds a predetermined value, the meshed state is checked, and measures such as correction are taken as necessary.

[0014]

As described above, the gear sound inspection system of the present invention applies a predetermined load to the gear mechanism incorporated in the differential case and detects the vibration generated in the gear mechanism in a state close to actual running. Therefore, the noise level can be measured more accurately than in the conventional case. In addition, by incorporating the vibration sensor of the vibration detection means into the clamper, the measurement location can be set to the same position each time, and variations in measurement accuracy can be reduced.

[Brief description of drawings]

FIG. 1 is an overall view of a gear sound inspection device of the present invention.

FIG. 2 is an enlarged vertical sectional view of a main part.

FIG. 3 is a bottom view seen from the direction AA of FIG.

FIG. 4 is a graph showing a correlation between a front side differential vibration and a noise value.

FIG. 5 is a graph showing a correlation between a rear differential vibration and a noise value.

[Explanation of symbols]

3 ... Clamp base, 4 ... Motor, 5 ... Torque load / detection device, 6 ... Clamper, 8 ... Vibration sensor, W ... Differential case.

Claims (2)

[Claims] 1. A rotary drive means for rotationally driving a gear mechanism incorporated in a differential case at an arbitrary rotational speed,
A gear sound inspecting device comprising: a load unit that applies a predetermined load to the gear mechanism during the rotational driving, and a vibration detection unit that detects a vibration generated in the gear mechanism during rotation. 2. The gear noise inspection device according to claim 1, wherein the device includes a clamper for positioning and fixing the differential case, and a vibration sensor of the vibration detecting means is incorporated in the clamper. Gear sound inspection device.