JPH04120411A - Detecting apparatus for groove of component such as cam shaft - Google Patents

Abstract

PURPOSE:To securely detect existence of a groove by deciding the existence of the groove of an object to be detected by a difference in distances between a sensor and a part without groove and between the sensor and a groove forming part. CONSTITUTION:An eddy current sensor 2 is provided oppositely to an object 21 to be detected, while the object 21 can be horizontally moved by an object moving means 31. When existence of a groove of the object 21 is to be detected, a part without groove 22b of the object 21 is first made face the sensor 2 by the means 31. An electric signal transmitted from an oscillator 9 is input via an amplifier 8 to the sensor 2. An electric signal output from the sensor 2 in proportion to a distance 3b between the sensor 2 and the part without groove 22b is input via an amplifier 5 of a decision unit 4 and an A/D-converter 13 into a storage unit 14. Then a groove forming part 2a is moved via the means 31 to a position opposite to the sensor 2, and similarly a signal wherein a distance 3a from the groove forming part 22a is measured is stored in the storage unit 14. Then a differential signal between the distances 3a, 3b is calculated 15, thereby deciding 6 existence of the groove.

Description

[Detailed description of the invention] = Approximate date of purchase = [Industrial application field] The present invention detects the presence or absence of a groove in a detected object, for example, a component such as a camshaft, using a sensor. The present invention relates to a groove detection device.

[Conventional technology]

Conventionally, as shown in FIG. 5, a device for detecting whether or not there is a groove in a corresponding part of an object to be detected uses a sensor 302 at a groove forming part 322a, which is a position in an object 321 where a groove can be formed. There is something that is opposed to. In such a device 301, the distance 303 between the sensor 302 and the detected object 321 is measured by the sensor 302, and the value is
It is sent to a comparison unit 306, which is part of the determination unit 304 and has a reference value set in advance. The presence or absence of a groove is then determined by comparing it with the reference value.

[Problem to be solved by the invention]

In the conventional groove detection device 301 described above, the sensor 30
Since the distance 303 between 2 and the detected object 321 is measured as an absolute value, the axial diameter of the detected object 321 is larger than 303). There is a thing. Alternatively, the environment at the time of measurement, such as cutting water remaining in the detection area or changes in temperature and humidity, may make the measurement results inaccurate, which may also lead to erroneous judgment results.

Therefore, it has been an issue to provide a pressure detection device for a groove in a component such as a camshaft, which is not affected by variations in the shaft diameter of the object to be detected or by the environment during measurement.

=Structure of the invention= [Means for solving the problem] A sensor facing an object to be detected, and a groove of the object to be detected from a position where the non-grooved portion of the object faces the sensor. A detection object moving means for moving the forming part to a position facing the sensor, a distance between the non-grooved part of the detection object and the sensor measured by the sensor, and a distance between the groove forming part of the detection object and the sensor. The determination unit is provided with a determination unit that is input as a signal and has a reference value set therein for determining the presence or absence of a groove, and compares the reference value with a difference value between the two signals to determine the presence or absence of a groove.

[Examples and effects]

The configuration of an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a groove detection device 1 (hereinafter referred to as groove detection device) of a component such as a camshaft and a detected object 21 according to a first embodiment of the present invention.

This groove detection device 1 includes one eddy current sensor as an electromagnetic induction sensor. This eddy current sensor 2 faces an object to be detected 21 .

The detected object 21 can be moved in the horizontal direction in the drawing by a detected object moving means 31. This detected object moving means 3
Reference numeral 1 denotes a horizontal center stand 32 that supports both ends of the object to be detected 21, a ball screw 34 that is connected to the lower part of the horizontal center stand 32 and moves this horizontal center stand 32 in the horizontal direction in the drawing, and this ball screw. It is composed of a motor 33 that rotates a motor 34, and a bed 35 that supports these motors.

The connection state between the above-mentioned eddy current sensor 2 and other members is as follows.

It is connected to an oscillator 9, which is an electric signal transmission source, or to an amplifier 8, which in turn is connected to the eddy current sensor 2. Further, the eddy current sensor 2 is connected to a determination section 4. This determination section 4 includes an amplification section 5 connected from the sensor.
, followed by an analog-to-digital converter,
It is composed of a storage section 14, a calculation section 15, a comparison section 6, and a reference value setting section 7 for inputting a reference value for determining the presence or absence of a groove into the comparison section 6. The comparison section 6 and the reference value setting section 7 can be realized by hardware or software.

Next, a groove detection method using the above-mentioned groove detection device 1 will be explained.

When detecting the presence or absence of grooves on the detected object 21, the detected object 21 is first moved by the above-mentioned detected object moving means 31, and as shown by the solid line in FIG. Part 22
b is made to face the above-mentioned eddy current sensor 2. Then, an electric signal such as current or voltage is transmitted from the oscillator 9 and input to the amplifier 8.

input to sensor 2. Then, the eddy current sensor 2 outputs an electric signal proportional to the distance 3b from the grooveless portion 22b of the object to be detected 21, and inputs it to the amplifying section 5 constituting the determining section 4. The electrical signal that has become distance information after passing through the amplification section 5 is sent to the storage section 14 via the analog-to-digital conversion section 13.
is input.

Thereafter, as shown by the two-dot chain line in FIG.
2a is moved to a position facing the sensor 2. Then, as described above, an electric signal such as current or voltage is transmitted from the oscillator 9 and input to the amplifier 8. The amplified electrical signal is input from the amplifier 8 to the eddy current sensor 2 . Then, the eddy current sensor 2 detects the non-grooved portion 22 of the detected object 21.
An electrical signal proportional to the distance 3b from the terminal 3b is output and input to the amplifying section 5 that constitutes the determining section 4. The electrical signal that has passed through the amplification section 5 and has become distance information is input to the storage section 14 via the analog-to-digital conversion section 13. Then, since the distance 3a from the non-grooved portion 22b is maintained, the difference between the newly obtained distance 3a from the grooved portion 22a and the measured electric signal is determined by the calculation unit 15, and the comparison unit 6 is input.

Since the reference value for determining the presence or absence of a groove is inputted to the comparative light section 6 from the reference value setting section 7, the comparison section 6 determines the presence or absence of a groove.

As shown in Figure 4, the reference values here refer to the upper and lower limits of the range of output voltage, etc. that is determined to be grooved, and the upper and lower limits of the range of output voltage, etc., that is determined to be grooved. That's true. These values may be determined in advance through experiments. When actually detecting the presence or absence of a groove, if the difference between the values of voltage etc. obtained from the detected object 21 is included in either of the two reference value ranges mentioned above, it is better to include that value within the range. This is the judgment result.

In this way, the presence or absence of grooves in the detected object 21 is detected based on the difference in the distance 3a between the eddy current sensor 2a and the grooved part 22a and the distance 2b between the eddy current sensor 2b and the non-grooved part 22b. There is a wide variation in the shaft diameter of the detected object 21 (but
There is no error in the judgment result of the presence or absence of grooves. Furthermore, even in a bad environment, such as when cutting water or the like remains in the detection area, the grooved part 22a and the non-grooved part 22b of the detection object 21 are in the same environment, so there is no negative effect on the determination result. There is only so much.

In the groove detection device according to the first embodiment of the present invention, the sensor or the eddy current sensor is used, and the signal is electrical, but the sensor and the signal may be of other types as described below. Furthermore, an air cylinder may be used as the detection object moving means.

In the groove detection device 101 according to the second embodiment of the present invention, as shown in FIG. 2, the sensor is an air sensor.

This groove detection device 101 is equipped with one air sensor, and this air sensor 102 is connected to the detected object 121.
is facing. Since no groove is formed in the groove forming portion 122a of the object to be detected 121, the groove forming portion 122a is shown with diagonal lines in FIG.

In this groove detection device 101, an air sensor 102
It is the same as the groove detection device according to the first embodiment in that it is connected to the determination unit 104 and that it has a detection object moving means (not shown), so a description thereof will be omitted. do.

In the determination section 104, a differential pressure gauge may be used instead of the amplification section 105.

On the other hand, air is supplied to the air sensor 102 from an air source 109 via a pressure regulating valve 108. Furthermore, a pneumatic converter 110 is installed between the air sensor 102 and the amplification section 105.

Therefore, in this case, the comparison with the reference value in the determination unit 104 is performed as an electrical signal.

The nozzle diameter, outer diameter, etc. of the above-mentioned air sensor 102 are set similarly to a normal air micrometer.

Next, a groove detection method using the groove detection device 101 described above will be explained.

When detecting the presence or absence of a groove in the detected object 121, first, the non-grooved portion 122b of the detected object 121121 is made to face the aforementioned air sensor 102 by the above-described detected object moving means. Then, air is supplied to the air sensor 102 from an air 1109 such as a compressor. Air source 109 and sensor 1
The air pressure is adjusted by a pressure regulating valve 108 provided between the air pressure and the air pressure. The air supplied to the sensor 102 is ejected (1
12) To be done. Then, the pressure sensed by the air sensor 102 is input to the determination unit 104 as an electrical signal via the pneumatic converter 110.

Thereafter, the above-described object moving means moves the object 121 to a position where its rounded portion 122a faces the air sensor 102, as shown by the two-dot chain line in FIG. Then, as described above, air is supplied from the air source 109 to the air sensor 102. The obtained pressure is transmitted to the determination unit 1 as an electric signal via the pneumatic converter 110.
04 is input. Then, the electrical signal obtained when measuring the distance 103a to the non-grooved portion 122b is stored in the storage section 114.
15, it is determined whether there is a groove. In the case of this embodiment, since no groove is formed in the groove-formed portion 122a, the air sensor 102 senses substantially the same pressure on both the groove-free portion 122b and the groove-formed portion 122a, and therefore the comparison portion Since there is a difference between the two electrical signals inputted to 106, there is no difference, or even if there is, it is very small, so it is determined that there is no groove.

In this way, since the presence or absence of a groove on the detected object is determined based on the difference in the distance 103a between the air sensor 102 and the groove forming part 122a and the distance 103b between the air sensor 102 and the non-grooved part 122b, the detected object Even if there is a large variation in the shaft diameter of the shaft 121, there is no error in the determination result of the presence or absence of a groove. Furthermore, even in a bad environment such as when cutting water or the like remains in the detected area or where the temperature and humidity change, the grooved portion 122a and the non-grooved portion 122b of the detected object 121 are in the same environment. It will not adversely affect the judgment results.

Using the groove detection device 1 (101) as described above, the third
As shown in the figure, the presence or absence of an actual mechanical part can be detected, and the model of the part can be identified based on the result. As shown in FIG. 3, 91 is a camshaft as an object to be detected with grooves formed on the outer peripheral surface of the journal.
, 71, the groove forming portion 42a of 41, 51.71.

Grooves 42, 52, 72 are formed in 52a, 72a, and no groove is formed in the groove forming portion 62a of the journal 61 shown by diagonal lines. and four sensors 40, 50,
60 and 70 each face the journal. When detecting grooves, first, as shown in FIG.

52b, 62b, 72b as sensors 40, 50, 60.7
0 and measure the distance between each sensor and each grooveless part to obtain an electric signal.

Thereafter, the camshaft is moved by the detection object moving means to form the grooves 42a, 52a, 62a.

72a is made to face the sensors 40, 50, 60, 70, and the distance between each of these sensors and each grooveless portion is measured to obtain an electric signal from each of them. After these, for each journal,
The presence or absence of a groove is determined for each journal by comparing the difference between the distance between the sensor and the groove-free portion and the distance between the sensor and the groove-formed portion with a reference value. That is, it is determined that the journal 41.degree. 51.72 has a groove, and the journal 61 does not have a groove. As a result, it is possible to identify that this camshaft 91 is a specific model.

Note that the groove detection device according to the present invention can be used to detect grooves not only in camshafts but also in other parts.

=Effects= As described above, according to the present invention, in a device for detecting grooves in a component such as a camshaft, a sensor facing the object to be detected and a groove-free portion of the object to be detected are connected to the sensor. Distance between the non-grooved part of the object and the sensor Then, the distance between the groove forming part of the object to be detected and the sensor is input as a signal, and a reference value for determining the presence or absence of a groove is set, and the value of the difference between the reference value and these two signals is input. and a determination section that determines the presence or absence of a groove by comparison, and the presence or absence of a groove on the object to be detected is determined based on the difference in the distance between the sensor and the non-grooved portion and the distance between the sensor and the grooved portion. Even if there is a wide variation in the shaft diameter of the object to be detected (but there is no error in the judgment result of the presence or absence of grooves, and even if the environment at the time of measurement is bad, the grooved part and the non-grooved part of the object to be detected will be the same). Since they are placed under the same environment, they do not affect the judgment results.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a groove detection device for a component such as a camshaft and a detected object according to a first embodiment of the present invention, and FIG. 2 is an explanatory diagram of a cam according to a second embodiment of the present invention. Explanatory diagram of a detection device for grooves in parts such as shafts and objects to be detected, Part 3
Figure 4 shows reference values and determination results in the apparatus for detecting grooves in parts such as camshafts according to an embodiment of the present invention. FIG. 5 is an explanatory diagram of a conventional groove detection device and an object to be detected. (Explanation of symbols) 2. -Sensor. 3a, 3b... Distance. 4. Judgment section. 21. ・Object to be detected. 22a. Groove forming part. 22b・・Grooveless part. 31. ・Detection object moving means.

Claims (1)

[Claims] The sensor 2 faces the detected object 21, and the detected object 21 is moved from a position where the grooveless portion 22b of the detected object 21 faces the sensor 2 to a position where the grooved portion 22a of the detected object 21 faces the sensor 2. a distance 3b between the grooveless portion 22b of the detected object 21 and the sensor 2, which is measured by the sensor 2;
The distance 3a between the groove forming part 22a of the detected object 21 and the sensor 2 is input as a signal, and a reference value for determining the presence or absence of a groove is set, and the difference between the reference value and the two signals is input as a signal. 1. A determination unit 4 for determining the presence or absence of a groove by comparing the value of .