JPH0363574A - Inspecting method for revolving speed detecting device - Google Patents

Abstract

PURPOSE:To detect the abnormal variation of a revolving speed signal by providing a light reflecting surface to a gear installed on a rotating body, arranging a projecting and photodetecting device opposite it, and specifying an abnormal position of the gear according to the reference position signal of the projecting and photodetecting device and the revolving speed signal of an electromagnetic pickup. CONSTITUTION:The gear 2 is rotated as a revolving shaft 1 rotates, an electric signal 4 of frequency corresponding to the revolving speed is inputted to an F/A converting device 5 by the electromagnetic pickup 3, and a revolving speed is outputted. The irradiation light of a photoelectric probe 8 is reflected by a reflecting tape 7 and outputted to a recording device 10 as a reference position signal 9, The recording device 10 records the reference position signal 9 and revolving speed signal 6 for >= rotation of the gear 2 to detect the abnormal part of the gear 2. Consequently, the abnormal variation of the revolving speed signal can easily be detected.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a method for inspecting abnormal locations in a gear installed on a rotating body and a gear of a rotation speed detection device that detects the rotation using an electromagnetic pickup. Regarding.

(Prior art) The tachometer-generator type is conventionally well known as a device for detecting the rotational speed of a rotating body, but in recent years, the electromagnetic pickup type has been increasingly used due to its excellent responsiveness and reliability. .

In this electromagnetic pickup type rotational speed detection device, as shown in a perspective view of a main part in FIG. 3, a gear 2 fixed to a rotating shaft 1 of a rotating body rotates integrally with the rotating shaft 1. An electromagnetic pickup 3 is placed on the outer periphery of the gear 2 close to the tooth tip 2a, for example, at a distance of 0.5 mm or less. As the rotating shaft l rotates, the tooth tip 2a and the tooth bottom 2b of the gear 2 alternately pass through the electromagnetic pickup 3, thereby changing the magnetic flux density in the electromagnetic pickup 3 and outputting a sine wave electric signal 4. be done. The frequency of this electric signal 4 increases as the rotational speed of the gear 2 increases, and decreases as the rotational speed decreases. That is, the rotational speed of the rotating body 1 and the frequency of the electric signal 4 are in a proportional relationship. Therefore, this electric signal 4 is input to the F/V converter 5, and a rotation speed signal 6 which is a DC voltage corresponding to the frequency is input.
The rotational speed is displayed or the speed is controlled via a tachometer or a control device (not shown).

(Problem to be Solved by the Invention) Since the gap between the electromagnetic pickup 3 and the gear 2 is extremely small, if there is an abnormality such as a rather deep scratch on the surface of the tooth tip 2a of the gear 2, the tooth tip 2a Electrical signal at position 4
As a result, the accuracy of the rotational speed signal 6 from the F/V converter 5 decreases.

This is because the F/V converter 5 is configured in advance to detect the rotation speed only when an input terminal of a predetermined value or higher is input as a noise countermeasure. The electromagnetic pickup 3 rotates the rotating body 1
The output value of the electrical signal 4 was measured in detail, and the presence or absence of scratches on the gear 2 was visually inspected. However, in general, the tooth tips 2a of the gear 2 are minute, and the number of teeth is extremely large, about 300, which poses a problem in that both measurement and inspection require a great deal of labor from the operator.

The present invention has been made in view of the above, and its purpose is to provide a light reflecting surface on the gear of a rotation speed detection device and a light emitting/receiving device at a position opposite to the light reflecting surface, so that future reference position signals can be detected. It is an object of the present invention to provide an inspection method for a rotation speed detection device that reduces the burden on a worker who identifies an abnormal position of a gear from a rotation speed signal.

[Objective of the Invention] (Means for Solving the Problems) A light reflecting surface provided on the gear of a rotating body rotation speed detection device using a gear installed on a rotating body and an electromagnetic pickup provided close to the gear; The apparatus includes a light projecting and receiving device installed at a position facing the light reflecting surface, and a recording device for recording a reference position signal from the light projecting and receiving device and a rotational speed signal from the electromagnetic pickup.

(Function) If there is a scratch on the tooth tip of the gear, the output of the electrical signal from the electromagnetic pickup at that location will be abnormal, and the F/F/
An abnormality also appears in the output of the rotational speed signal outputted through the V converter at the corresponding tooth tip position. In addition, since the light emitting and receiving device periodically emits a pulsed reference position signal at the position of the light reflecting surface, the abnormal part of the rotation speed signal and the reference position signal are recorded with a recording device and compared. The defective tooth tip can be identified by counting the number of pulsations up to the abnormal portion in the rotational speed signal from the reference position signal.

(Example) An embodiment of the present invention will be described with reference to the drawings.

Note that the same components as those in the prior art described above are given the same reference numerals and detailed explanations will be omitted.

FIG. 1 is a perspective view of a main part. A gear 2 is fixed to the tip of a rotating shaft 1 of a rotating body and rotates together with the rotating shaft 1. FIG.

An electromagnetic pickup 3 is placed on the outer periphery of the gear 2 at the tooth tip 2a with a gap of, for example, 0.5 degrees or less. In this electromagnetic pickup 3, when the tooth tips 2a and the tooth bottoms 2b of the rotating gear 2 pass alternately, the magnetic flux density in the electromagnetic pickup 3 changes and outputs a sinusoidal electric signal 4.

The frequency of this electric signal 4 and the rotation speed of the rotating body 1 are in a proportional relationship, and this electric signal 4 is manually input to the F/V converter 5, which converts the DC voltage corresponding to the frequency. Outputs rotation speed signal 6. Further, a reflective tape 7, which is a light reflecting surface, is attached to the position of the tooth tip 2a arbitrarily set as a reference on the side surface of the gear 2, and the reflective tape 7 is irradiated with light at a position facing this, and the reflected light is A photoelectric probe 8 which is a light emitting/receiving device that receives the signal and outputs it as a reference position signal 9 of electric pulses is installed. Furthermore, the rotation speed signal 6
The reference position signal 9 is manually compared with the reference position signal 9 by a recording device 10 such as an analyzer recorder.

Next, the effect of the above configuration will be explained. The gear 2 rotates together with the rotation of the rotating shaft 1, and an electric signal 4 having a frequency corresponding to the rotation speed is outputted from the electromagnetic pickup 3 to the F/V converter 5. The F/V converter 5 converts this electric signal 4 into a DC voltage proportional to its frequency, that is, the rotation speed of the rotating shaft 1, and outputs a rotation speed signal 6. This rotational speed signal 6 is output as one input of the recording device 10, and is also output to a rotational speed meter or a control device (not shown).

In addition, in the photoelectric probe 8, light is always irradiated from the light projecting part to the side surface of the gear 2, but this irradiated light is reflected when the reflective tape 7 comes to the position of the photoelectric probe 8, and the reflected light is The signal is input to the light receiving section of the probe 8 and output to the recording device 10 as a reference position signal 9 of electric pulses. The reflective tape 7 is usually attached to one location on the side surface of the gear 2 so that the reference position signal 9 is generated each time the gear 2, that is, the rotating shaft 1 rotates once.

When inspecting the rotation speed detection device during periodic inspections, etc., the reference position signal 9 of the photoelectric probe 8 and the rotation speed signal 6 from the F/V conversion device 5 are input to the gear 2 in the recording device IO.
Records over rotations.

This record is read out onto a recording paper and enlarged as necessary, as shown in FIG. 2, to detect an abnormal portion on the curve of the rotational speed signal 6. For example, when a low output abnormality part 11 is discovered, the part including the abnormality part 11 and the reference position signal 9 is enlarged, and the number of pulsations of the rotation speed signal 6 up to the abnormality part 11 is measured from the reference position signal 9 as a base point. For example, if it is the 14th tooth tip, it can be seen that there is a defect such as a scratch on the L4th tooth tip compared to the reference tooth tip to which the reflective tape 7 is attached.

The pulsations in the rotational speed signal 5 shown in FIG. 2 are due to fluctuations in the output signal due to changes in the gap between each tooth tip 2a and the electromagnetic pickup 3.

[Effects of the Invention] According to the present invention, abnormal changes in the rotation speed signal can be easily detected, and defective tooth tips that reduce the accuracy of the rotation speed detection signal, such as scratches on the tooth tips of gears, can be easily detected. This has the effect of improving the reliability of the rotation speed detection device and reducing the burden on inspection workers.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a main part of an embodiment of the present invention, FIG. 2 is a characteristic curve diagram of test results of the present invention, and FIG. 3 is a perspective view of a main part of a conventional rotation speed detection device. 1... Rotating shaft, 2... Gear, 2a...
Tooth tip, 2b... Tooth bottom, 3... Electromagnetic pickup, 4... Electric signal, 5... F/V converter, 6... Rotation speed signal, 7... Reflective tape, 8・
...Photoelectric probe, 9...Reference position signal, 10...
- Recording device, 11... Abnormal part.

Claims (1)

[Claims] A rotation speed detection device using a gear installed on a rotating body and an electromagnetic pickup provided close to the gear; a light reflecting surface on the gear; and a light emitting/receiving device at a position facing the light reflecting surface; is determined from a reference position signal from the light emitting/receiving device and a rotation speed signal from the electromagnetic pickup.