JP2985191B2 - Inspection method for gear teeth - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for accurately inspecting the tooth contact state of a pair of gears to be meshed in order to make the tooth contact of the gears to be meshed properly.

(Prior Art) As a conventional method for inspecting a gear tooth contact, there is, for example, a method described in JP-A-60-82905.

In this conventional method, the peeling state or the transfer state of the paint applied to the tooth surface of one gear of a pair of gears to be meshed after the meshing drive is imaged by a video camera or the like, and the obtained image is subjected to image processing to perform predetermined processing. Is evaluated and the tooth contact state is inspected, that is, the quality of the tooth contact and the quality grade are determined based on the evaluation parameters.

(Problems to be Solved by the Invention) However, in such a conventional tooth contact inspection method, since, for example, Komitsutan is used as the paint, the portion where the paint is applied on the tooth surface of the gear (or transfer). The boundary between the part where the paint has peeled off and the part where the paint has peeled off (or the part where the paint has not been applied) can be distinguished from the shade difference in the image. It was necessary to specify the application technique, the type of Komyotan, and the irradiation angle of the lighting device with respect to the tooth surface. That is, before the inspection, the tooth surface is sufficiently washed, and unless the paint is applied thickly, the above-mentioned difference in shade cannot be obtained. It is only possible to use Kometan (less oil), and it is necessary to use a highly convergent spotlight as an illuminating device to illuminate from a very limited irradiation angle depending on the type of work (vehicle type). there were.

It should be noted that, for example, a method using an ultraviolet lamp as an illuminating device and using a paint containing a fluorescent pigment that reacts to the ultraviolet light as a paint can be considered.In this case, when capturing an image, for example, cutting off disturbance light by using a dark room,
Further, unless the reflected light of the ultraviolet light itself from the tooth surface is also cut, it is difficult to obtain a suitable density difference.

The present invention is a paint containing a fluorescent pigment applied to the tooth surface of the gear,
An object of the present invention is to solve the above-described problem by performing imaging using a filter that transmits only electromagnetic radiation of a predetermined wavelength that emits in response to irradiated electromagnetic radiation.

(Means for Solving the Problems) For this purpose, the gear tooth contact inspection method of the present invention comprises:
A paint containing a fluorescent pigment is applied to the tooth surface of any one of the pair of gears, and this one gear is rotated by meshing with the other gear to which the paint is not applied, and any one of the pair of gears is rotated. Irradiate electromagnetic radiation to react the fluorescent pigment on one side, through a filter that transmits only electromagnetic radiation of a predetermined wavelength emitted by the fluorescent pigment in response to this irradiation,
An image capturing unit captures an image of the state of peeling of the paint applied to the tooth surface of the one gear or the state of adhesion of the paint transferred to the tooth surface of the other gear, and based on the obtained image, the pair of gears The state of contact of the teeth is inspected.

(Operation) According to the method of the present invention, after a paint containing a fluorescent pigment is applied to one tooth surface of a pair of gears to be meshed, the pair of gears is driven to mesh, and one of the gears selected as an inspection target. The tooth surface of the gear is imaged by an imaging means (for example, a television camera) equipped with a filter described below under irradiation of electromagnetic radiation (for example, ultraviolet light) for reacting the fluorescent pigment. As the filter used here, a filter having a characteristic of transmitting only electromagnetic radiation of a predetermined wavelength emitted by the fluorescent pigment in response to the irradiation is used.

As a result, disturbance light and reflected light of the irradiation electromagnetic radiation itself are cut, and the difference in contrast (contrast) between the portion where the paint exists and the portion where the paint does not exist in the captured tooth surface image becomes clear. Boundary, paint application technology,
It can be identified very accurately without being affected by the type of Komyotan and the illumination angle of the lighting device (this requires readjustment when the type of gear as the workpiece changes). Furthermore, since the inspection can be performed without using a dark room, there is an advantage that the tooth contact inspection can be performed on the manufacturing and assembly lines without providing a special inspection line.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram illustrating the configuration of a tooth contact inspection system used for carrying out the method of the present invention. In FIG. 1, reference numeral 10 denotes a gear to be evaluated, and in this example, a hypoid gear is used.

As the gear 10, any one of the gears after applying a paint 11 to the tooth surface of one of the pair of gears and meshing and driving the same with a driving device (not shown) is used. Therefore, the paint 11 adheres to the tooth surface 10a by application or transfer. The coating material 11 (for example, Komitsutan) contains a fluorescent pigment, and in this example, Shinroyhicolor (trade name) orange is used as the fluorescent pigment. As shown in FIG. 5, the fluorescent pigment is an organic fluorescent pigment having a main fluorescence emission wavelength of 600 [nm].

The gear 10 is rotatably positioned and mounted on a turntable-like rotating device 12, and starts the following measurement on the tooth surface at a predetermined position defined by the rotation start point positioning device 13, and completes the gear. Until the measurement of the tooth surface is completed, it rotates by a predetermined angle every time under the control of the control device 16 described later.

The tooth surface 10a of the gear 10 is illuminated by the illumination device 14. As the illumination device 14, an ultraviolet lamp, in this example, 365 [n
m] is used as the main emission wavelength, and a black light that emits only long-wave ultraviolet light of 310 to 400 [nm] (its spectral characteristics are shown in FIG. 6) is used. It is not necessary to darken the surrounding environment, but a dark room is more preferable.

The tooth surface 10a illuminated by the illumination device 14 is
An image is taken by the filter 5 through the filter 20. In this example, two filters of the CM-500 and O-58 types manufactured by Kenko Co. (orange color filter and infrared cut filter) are used in combination as the filter 20 (the spectral characteristics are shown in FIG. 7). The imaging is a rotation start point positioning device
Based on a command from the control device 16 that monitors the rotation of the 13, the tooth surfaces 10a are always synchronized with each other so that imaging can be performed under the same conditions, and the tooth surface 10a and the television camera 15 form a predetermined angle. And

Image data from the television camera 15 is input to the image processing device 17. The image processing device 17 is connected to the control device 16, and the control device 16 further has an operation display panel 18 for performing manual operations such as setting of a corresponding type of gear, starting measurement, and displaying a determination result.
Connect.

The control device 16 performs the second operation based on the input information from the rotation start point positioning device 13, the image processing device 17, and the operation display panel 18.
By executing the control program shown in the figure, the entire system is controlled, and the image processing device 17 includes the television camera 15 and the control device.
The control program of FIG. 3 is executed based on the input information from 16 to perform image processing of the tooth surface image.

That is, first, the system is started in step 101 of FIG. 2, the automatic operation mode is selected in step 102, and the model of the gear corresponding to the work is set in step 103. by). In the next step 104, it is determined whether or not the work is seated (this determination is made, for example, by a seating sensor (not shown) provided on the rotating device 12). If the work is not seated, the control returns to step 102. For example, in step 105, the judgment result display lamp ("O" provided on the operation display panel 18)
The two lamps “K” and “NG” are reset to reset the display of the result of the previous work determination, and in step 106, the rotation start point is positioned. This positioning is completed when the rotation start point positioning device 13 is brought into contact with the work to fix the work at a predetermined position, and then receives a positioning completion signal issued when the device 13 is released from the work.

In the next step 107, an image processing start command is issued, for example, by operating the operation panel 18. In step 108, image processing of the tooth surface image at the current positioning position is performed by a subroutine shown in FIG. When the image processing completion signal is received in the next step 109, step 110 is performed so that the workpiece can be imaged by the television camera 15 at the next processing target tooth surface.
Then, the rotating device 12 is operated to rotate the work by a predetermined angle, and the control proceeds to a loop of steps 111-108 to 111 to perform image processing of the tooth surface.

When the image processing of all tooth surfaces is completed in this way, in the next step 112, the determination result signal (which is transmitted from the image processing device 17) is determined. Here, if there is no determination result signal (for example, in the case of a transmission error), control is returned to step 107, and the above-described image processing is performed again. When an OK signal is received, the “OK” determination result of the operation display panel 18 is received in step 113. When the indicator light is turned on and the NG signal or the judgment error signal is received, the "NG" judgment result indicator light is turned on in step 114. In this case, this display is reset in step 115 (for example, this reset is performed by the operator operating the operation display panel 18 after confirming the display). If this reset operation is not performed, step 116 is performed while the workpiece is seated. Repeat the loop of −115−116 to enter the standby state and rotate the work
When detached from 12, an alarm is output in step 117.
This alarm is reset in step 119 after resetting the NG and determination error signal in step 118.

Next, image processing will be described with reference to FIGS. 3 and 4. FIG. First, at step 131 in FIG. 3, a tooth surface image is fetched, and at step 132, this image is binarized. The image captured at this time is as shown in FIG. 4 (a). (Note that one of the gears coated with paint and the gears not coated with paint will be described here. When the image is binarized, a graphic P appears in the tooth surface as shown in FIG. In the next step 133, based on the vehicle type setting in step 103 in FIG. 2, a mask process is performed by using the contour shape of the tooth surface taught in advance (in this example, a hexagon), as shown in FIG. Then, the part other than the target tooth surface is excluded.

Next, in step 134, noise removal processing is performed. This removes the isolated portion outside the tooth contact pattern P, which is the largest area in the mask, as shown in FIG. Is not affected either. At step 135, a tangent search is performed on the obtained tooth contact figure P. That is, as shown in FIG. 5E, the figure P is surrounded by six tangents parallel to each side of the mask, and a hexagon formed by these tangents is defined as a tangent window. Next, in step 136, black-and-white inversion is performed as shown in FIG. 17F, and in step 137, the mask processing using the tangent window is performed as shown in FIG.

In the next step 138, the ratio a: b: c of the lengths of the three parts defined in the tooth ridge direction by the respective tangents is determined as shown in FIG. Note that, here, the above ratio is obtained by obtaining an intersection with a tangent in the tooth direction on a line connecting the lower left and right points of the tooth surface, but an average value is obtained on another line, for example, on the center line. You may.
At the next step 139, the tooth contact position is determined based on this ratio. This determination is made, for example, by the ratio per tooth determined from the ratio a: b: c. And grade of tooth contact based on | ac−c | and OK or NG depending on whether this grade exceeds the standard
Is determined.

Similarly, in the next step 140, the ratio x: y: z of the lengths of the three parts defined in the tooth-gear direction by the above tangents is determined as shown in FIG. It is determined on a line connecting M and point N). Further, in step 141, as shown in FIG. ₁₄ (i), the areas S ₁ , S ₂ , S ₃ , and S ₄ of the four corner regions of the tangent window defined by the tangent window and the tooth contact pattern P are determined. In step 142, ups and downs per tooth are determined based on these areas S ₁ , S ₂ , S ₃ , S ₄ and the ratio x: y: z. Note that this determination is based on, for example, the ratio This is performed in the same manner as in step 139 based on the deviation | x−z | of the tooth contact and the area ratio S ₁ : S ₂ : S ₃ : S ₄ .

In the next step 143, based on the determination results in steps 139 and 142, a tooth contact inspection of this work, that is, a comprehensive determination of the tooth contact quality is performed. This determination is OK or NG. If no determination is obtained, a determination error is determined, and the determination result is stored in the storage device.

Next, the operation of this example will be described in detail with reference to the characteristic diagrams of FIGS.

The fluorescent pigment used in this example, that is, orange of Sinloich Color (trade name), has a wavelength of 600 as shown in FIG.
The fluorescence intensity has a sharp peak near [nm], so that a single wavelength suitable for the inspection method of this example can be obtained. For comparison, in the case of lemon yellow of the Sinloich color shown by a dotted line in the same drawing, the wavelength distribution is wider than that of orange. On the other hand, the ultraviolet lamp has a peak value of 365 [nm] as a main emission wavelength as shown in FIG.
It is distributed over the range of 00 [nm].

When such a fluorescent pigment-containing paint (Koumeitan) and an ultraviolet lamp are used in combination, a remarkable peak value is observed in the wavelength range of 560 to 620 [nm] (illustration A) as shown in FIG. This is nothing less than the effect of including the fluorescent pigment in the paint.

In order to transmit only the wavelength in the range A, the seventh
By using a combination of two filters having the characteristics shown in the figure, a filter that transmits only the wavelength of 560 to 720 [nm] including the range A can be formed.

In this way, image processing is performed by capturing only light rays from the paint containing the fluorescent pigment present on the tooth surface, so that disturbance light or irradiation ultraviolet light itself is cut to shade the boundary between the existing part and the non-existent part of the paint. The difference allows very accurate identification. In this case, since there is no limitation on the application technique of the paint, the type of Komitsutan, the irradiation angle of the lighting device, and the use of the dark room, a highly flexible tooth contact inspection, and therefore, online tooth contact inspection on the manufacturing and assembly lines is possible. become.

(Effects of the Invention) Thus, as described above, the method for inspecting the tooth contact of a gear according to the present invention allows the paint containing the fluorescent pigment applied to the tooth surface of the gear to emit only electromagnetic radiation of a predetermined wavelength which is radiated in response to the irradiated electromagnetic radiation. Since imaging is performed using a transmitting filter, the boundary between the existing portion and the non-existing portion of the paint can be very accurately identified by shading differences by cutting off the disturbance light or the irradiation electromagnetic radiation itself. Since there is no limitation on the coating technique, the type of Komyotan, the irradiation angle of the lighting device, and the use of a dark room, a highly flexible tooth contact inspection, and thus, an online tooth contact inspection on a manufacturing and assembly line becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the configuration of a tooth contact inspection system used for carrying out the method of the present invention, FIG. 2 is a flowchart showing a control program of a control device in the same example, and FIG. 4 (a) to 4 (i) are diagrams each illustrating an image processing situation corresponding to the control program of FIG. 3, and FIGS. 5 to 7 are respectively fluorescent pigments and ultraviolet rays used in the same example. FIG. 8 is a characteristic diagram showing spectral characteristics of a lamp and a filter. FIG. 8 is a characteristic diagram showing spectral characteristics when the fluorescent pigment and the ultraviolet lamp are used in combination. 10: gear, 10a: tooth surface 11: paint containing fluorescent pigment, 12: rotating device 13: rotation start point positioning device 14: lighting device (ultraviolet lamp) 15: television camera 16: control device , 17 ... Image processing device 18 ... Operation display panel, 20 ... Filter

Continuation of the front page (58) Fields investigated (Int.Cl. ⁶ , DB name) G01M 13/02 G01M 3/20 G01N 21 / 88,21 / 64,21 / 25 G01B 11/24 G06F 15/62 H04N 7 / 18

Claims (1)

(57) [Claims] 1. A paint containing a fluorescent pigment is applied to the tooth surface of one of a pair of gears, and one of the gears is rotated by meshing with the other gear not coated with the paint. One of the gears is irradiated with electromagnetic radiation that causes the fluorescent pigment to react, and in response to this irradiation, a filter that transmits only electromagnetic radiation of a predetermined wavelength emitted by the fluorescent pigment, the imaging means causes An image of the peeling state of the paint applied to the tooth surface of the gear or the image of the adhesion state of the paint transferred to the tooth surface of the other gear is captured, and the tooth contact state of the pair of gears is determined based on the obtained image. A gear tooth contact inspection method characterized by inspecting.