JP2019105500A - Inspection method for gears - Google Patents

Abstract

To provide an inspection method for smaller scale and simple gears, reducing inspection time of gears.SOLUTION: The inspection method for gears according to the present invention includes steps of connecting a torque meter 12 to a gear to be inspected, driving the gear by a gear drive 13, and acquiring the rotational torque of the gear from the torque meter 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method of inspecting a gear.

  The differential gear mounted on a vehicle may be damaged during assembly, which may cause noise and lead to noise. Heretofore, an inspection apparatus for detecting abnormal noise has been used as a method for inspecting abnormal noise of differential gears. Patent Document 1 discloses a gear inspection apparatus that rotates a differential gear, measures vibration using a vibration sensor, and obtains a noise value from the correlation between the vibration and the noise value.

Japanese Patent Application Publication No. 08-136407

  In the case of using an inspection device for detecting abnormal noise, it has been necessary to move the differential gear in the process of assembly to the inspection device every time of inspection. In addition, the inspection apparatus is large in size and takes up a place, and there is a problem that nearly hundreds of N numbers (number of samples) are required to determine abnormal noise.

  The present invention has been made in view of the above problems, and aims to shorten the gear inspection time and to provide a smaller and simpler gear inspection method.

  A method of inspecting a gear according to the present invention includes the steps of: connecting a torque meter to a gear to be inspected; driving the gear by a gear drive device; and acquiring rotational torque of the gear from the torque meter And.

  In the method of inspecting a gear according to the present invention, the rotational torque of the gear is acquired from a torque meter to inspect the gear. Therefore, the gear inspection time can be shortened, and a smaller and simpler gear inspection can be performed.

  According to the present invention, inspection time can be shortened in gear inspection.

The gear test | inspection apparatus concerning embodiment is a photograph which shows the process of acquiring the rotational torque of a gear. It is a perspective view showing a gear rotation jig concerning an embodiment. FIG. 2 is an enlarged view of a region indicated by a broken line III in FIG. It is a figure which carried out FFT analysis about data of rotation torque of good goods concerning the example, and inferior goods, and showed it as a graph, and a figure which showed a difference of good goods and inferior goods as a graph.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. Also, in order to clarify the explanation, the drawings are simplified as appropriate.
As a matter of course, the right-handed xyz coordinates shown in FIGS. 1 to 3 are convenient for describing the positional relationship of the components. Usually, the z-axis plus direction is vertically upward, and the xy plane is a horizontal plane.

Embodiment
FIG. 1 is a photograph showing a process in which the gear inspection apparatus 1 according to the embodiment acquires the rotational torque of a gear.
In the gear inspection, as shown in FIG. 1, a sub-ASSY (assembly, assembly) SA which is in the middle of the assembling process is placed on the pallet P which is a mounting table. In the present embodiment, the differential gear is assembled to the sub-ASSY SA as a gear, but it can also be used for inspection on, for example, a spur gear or a planetary gear.

  As shown in FIG. 1, the gear inspection apparatus 1 is set to the gear. The gear inspection apparatus 1 in the present embodiment refers to a combination of the gear rotating jig 11, the torque meter 12 and the gear drive device 13. In the present embodiment, as shown in the photograph in FIG. 1, a nut runner is used as the gear driving device 13, but any device capable of driving and rotating a gear may be used. For example, using a motor etc. May be

  FIG. 2 is a perspective view showing a gear rotating jig according to the embodiment. First, the gear rotating jig 11 is connected to the gear portion. The gear rotating jig 11 has a shape in which a prismatic cavity is open at the center of the cylinder in the present embodiment, but can support the torque meter 12 described later, and prevents the torque meter 12 from rotating. It does not matter if it has no shape. The gear rotating jig 11 may be, for example, a cylinder having a cylindrical cavity.

  FIG. 3 is an enlarged view of a region indicated by a broken line III in FIG. The torque meter 12 is connected to the gear rotation jig 11 connected to the gear portion. The torque meter 12 is a device for measuring the rotational torque of the gear. Finally, the gear drive 13 is connected to the torque meter 12 to start gear inspection. The order of connecting the gear rotation jig 11, the torque meter 12, and the gear drive 13 may be reversed. For example, the gear rotation jig 11 and the torque meter 12 may be connected in advance and then connected to the gear to be inspected. After the connection, the gear, the gear rotation jig 11, the torque meter 12, and the gear drive 13 are in a connected state. The rotation of the gear drive 13 is transmitted to the gear via the torque meter 12 and the gear rotating jig 11. Then, the torque torque of the gear is measured by the torque meter 12.

  The data of the rotational torque acquired from the torque meter 12 is analyzed, and it is determined that the data indicating the data deviated from the non-defective standard value set to the desired value is the non-defective product. Various methods can be used to analyze the data. For example, a method of comparing the maximum amplitudes of rotational torques, fast Fourier transform (FFT) of the obtained rotational torques, and data There is a method of comparing the difference.

  When the gear is non-defective, the fluctuation of the rotational torque is small because the surface is less damaged. On the other hand, when the gear is defective, for example, when a gear nick or the like occurs, the rotation of the gear is not smooth and the rotational torque fluctuates. That is, it is considered that the rotational torque is affected by gear nicks and the like, and the gear nicks and the like cause abnormal noise. In other words, by measuring the rotational torque of the gear, it is possible to indirectly inspect the abnormal noise of the gear.

  Conventionally, in the case of using an inspection device for detecting abnormal noise, it has been necessary to move a differential gear in the process of assembly to the inspection device every time of inspection. In addition, the inspection apparatus is large in size and takes up a place, and there is a problem that nearly hundreds of N numbers (number of samples) are required to determine abnormal noise.

  In the present embodiment, the gear is inspected by acquiring the rotational torque of the gear using a torque meter and a gear drive. The use of a torque meter and a gear drive for gear inspection is simpler and smaller than conventional gear inspection devices. In addition, since the inspection apparatus itself can be moved, the gear can be inspected without changing the direction of the sub-ASSY while the gear in the process of assembly is flowing on the process. Furthermore, even a small N number can be properly inspected.

Next, examples of the present invention will be described.
EXAMPLES Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

  In this embodiment, a differential gear is used as the gear. First, non-defective gears and non-defective gears (with scratches) were prepared. In the present example, as an example, a defective product in which two teeth were damaged among a total of 15 teeth of the gears of the gears was prepared and used.

  Next, a gear rotating jig, a torque meter, and a nut runner as a gear drive were connected to the non-defective gear and the non-defective gear, and the rotational torque of each gear was measured using the torque meter. In this example, UTM II-100Nm (manufactured by Unipulse Corporation) was used as a torque meter. As a nut runner, a control box used Handy 2000 Lite and a tool used EH2-R2085-PH (manufactured by Estic Inc.). The number of rotations of the nut runner was 20 rpm (round per minute) for both good and bad products.

In the present example, FFT analysis was performed on the non-defective and non-defective rotational torque data acquired using the torque meter.
FIG. 4 is a graph showing FFT analysis of rotational torque data of non-defective and defective products according to the embodiment, and a graph showing the difference between non-defective and non-defective products. FIG. 4a is a graph showing the results of non-defective products, FIG. 4b the results of defective products, and FIG. 4c the difference between non-defective products and defective products. Further, FIG. 4 shows a power spectrum.

  As shown in FIG. 4c, when the non-defective result (FIG. 4a) is subtracted from the non-defective result (FIG. 4b), the difference between the non-defective waveform and the non-defective waveform is mainly within the range of 0 to 100 Hz. Arose. In this example, since the defective product is damaged in 2 teeth out of a total of 15 teeth of the gear of the gear, there is little damage, but it is considered that such a difference occurs in a relatively low frequency region .

  In the present embodiment, as described above, a result was obtained that a difference occurs between the non-defective waveform and the non-defective waveform within the range of 0 to 100 Hz. However, it is considered that the frequency band in which the difference between the non-defective product and the non-defective product occurs differs depending on the degree of the scratch attached to the non-defective product.

  For example, as in the present embodiment, in the case of a defective product with relatively few scratches, the degree of rotation and the frequency at which the rotational torque is affected is low, so the frequency at which the difference with the non-defective product is relatively low. It is considered that (for example, about 0 to 200 Hz).

  On the other hand, in the case of a defective product having a relatively large number of flaws, the degree of rotation and the frequency at which the rotational torque affects the frequency is high. Therefore, the frequency at which the difference from the non-defective product is relatively high.

  Therefore, the accuracy of the non-defective product to be obtained, that is, the reference value is set, and how many% deviates from the reference value to be a defective product can be appropriately changed depending on the desired product.

  As mentioned above, although the present invention was explained according to the above-mentioned embodiment, the present invention is not limited only to the composition of the above-mentioned embodiment, It is within the range of the invention of the claim of the present claim. Of course, it includes various modifications, modifications, and combinations that can be made by a vendor.

1 gear inspection device 11 gear rotating jig 12 torque meter 13 gear drive P pallet SA sub ASSY

Claims (1)

Connecting a torque meter to the gear to be inspected;
Driving the gear by a gear drive;
Obtaining the rotational torque of the gear from the torque meter.
Gear inspection method.