JPH0449539Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an encoder device that connects an electric circuit section and a detection section using an optical fiber.

[Conventional technology]

As shown in FIG. 8, the conventional optical fiber encoder device has an electric circuit section A and a detection section B configured separately, and the detection section B is connected to this electric circuit section by an optical fiber connector. The light emitted from the light emitting element 2 in response to the electric signal of the light emitting element drive circuit 1 of part A is transmitted from the receptacle 31 of the optical fiber connector 3 to the optical fiber 5 via the plug 32.
1, and the light is emitted from the lens 7 through the fixed slit plate 8 to the rotating disk 9. The light that does not pass through the slit of the rotating disk 9 and is reflected on the disk surface passes through the lens 7 again and is transmitted through the optical fiber 52 from the plug 42 of the optical fiber connector 4 to the receptacle 41, and the detected light is incident on the light receiving element 10 of the electric circuit section A. The light receiving element 10 converts the signal into an electric signal, and the waveform shaping circuit 11 compares it with a reference voltage to output a required rectangular wave signal.
The detected electric signal obtained from 0 varies in magnitude mainly due to the gap between the rotating disk 9 and the fixed slit plate 8 of the detecting section B and changes in the reflectance of the rotating disk 9. An adjustment circuit 12 is provided in the section to electrically adjust the detected electric signal to correct the variation. Note that a broken line 18 indicates the case of the detection section.

[Problem that the invention attempts to solve]

In this way, in the case where the electric circuit part A and the detection part B are configured separately and connected together by the optical fiber connectors 3 and 4, the adjustment of the detected value is converted into an electric signal and processed electrically. Therefore, if the electric circuit or the detection section is replaced due to a component failure, even if the electric circuit is adjusted in advance, the fluctuation state of the detection section may change after connecting with the optical fiber connector. It was necessary to readjust the adjustment circuit in the electric circuit section accordingly.

〔the purpose〕

The present invention provides compatibility between the electric circuit section and the detection section, which are connected through an optical fiber, and eliminates the need for readjustment at the time of replacement.

[Means for solving problems]

For this reason, the present invention is equipped with a light amount adjuster in the optical path passing through the transparent slit of the rotary disk in the detection section that causes fluctuations in the amount of light, and by reflecting a part of the light passing through the slit, the output light is The amount of light is optically adjusted to a predetermined level, eliminating the need for electrical adjustment.

"Function" Therefore, a constant amount of light is given from the input side optical fiber of the detection section according to the light emitting element of the electric circuit section, and the amount of light output from the output side optical fiber matches the reference voltage level of the waveform shaping circuit. If the light amount is adjusted using the light amount adjuster, the required rectangular wave signal output can be obtained by simply connecting the electric circuit section and the detection section with an optical fiber without readjusting after the connection.

〔Example〕

Hereinafter, embodiments of the present invention illustrated in the drawings will be described.

FIG. 1 shows an encoder device according to the present invention, which is composed of an electric circuit section A and a detection section B. The electric circuit section A includes a light emitting element drive circuit 1, a light emitting element 2, a light receiving element 10, and a detected electric power from the light receiving element 10. A waveform shaping circuit 11 for processing signals is provided, and optical fiber connectors 3 and 4 are provided opposite to the light emitting element 2 and the light receiving element 10.
receptacles 31 and 41 are provided. The detection unit B includes a fixed slit plate 8, a rotary disk 9 made of a reflecting plate attached to a rotating shaft 13 and provided with a light-transmitting slit, a lens 7, and a lens from the plugs 32, 42 of the optical fiber connectors 3, 4. 7 are provided with optical fibers 51 and 52 for transmitting light, and a light amount adjuster 6 is provided behind the rotary disk 9. As shown in FIG. 2, the light amount adjuster 6 includes a fixed base 62 that slidably supports a reflecting rod 61, and a rotating screw rod 63 provided on the fixed base is screwed into a screw hole of the reflecting rod 61. When the slits on the fixed disk 8 and the slits on the rotating disk 9 match, a part of the light passing through the slit on the rotating disk 9 is reflected by the reflecting rod 61. The light intensity change of the detection signal sent by the fiber 52 can be changed from V ₁ by protruding the reflecting rod 61 as shown in FIG.
V ₂ (dashed line).

If the detecting section B has failed and is to be replaced, the failed detecting section is removed from the electric circuit section A using the optical fiber connectors 3 and 4, and another detecting section B is connected.

The electric circuit section A uses the light from the light emitting element 2 to
The detection output reflected by the rotating disk 9 of the detection unit B is converted into an electrical signal by the light receiving element 10, and as shown in FIG. It is possible to obtain a rectangular wave output C that turns on and off at every 180° phase.

Therefore, if the amount of detected light changes due to changes in the reflectance of the rotating disk of the replaced detection unit B, the level of the detected electric signal decreases, for example, as shown by curve d in Figure 4, and the rectangular wave output ON-OFF
The phase of the light is shifted, and it is necessary to electrically readjust it. However, the detection unit B can be adjusted in advance by pushing out the reflection rod 61 using the rotating threaded rod 63 of the light amount adjuster 6 shown in FIG. The reflected light from the reflection rod 61 is added to increase the light intensity of the optical fiber 52, and the level of the detection output can be raised to match the reference voltage level of the electric circuit section A, and the connection of the optical fiber connectors 3 and 4 is made. By simply adjusting the output level of the light-receiving element 10 to the reference voltage, a desired rectangular wave signal C can be obtained without separate electrical adjustment.

In addition, when combining two output signals with a 180° phase difference, a fixed slit plate 81 is provided with the slit position shifted by 180° as shown in FIG.
A light quantity adjuster 6 has a lens 7 facing each lens 82, and a threaded portion of a reflecting rod 61 having a length corresponding to the mutual pitch of the lenses 7 is screwed into a threaded hole 64 of a fixed base 62 behind the rotary disk 9. is provided.

Therefore, if the light intensity of the detection output on the fixed slit plate 81 side is curve A+ in FIG. Unable to obtain wave output. Therefore, by moving the reflecting rod 61 toward the fixed slit plate 82 using the light amount adjuster 6 to reduce the amount of reflection on the fixed slit plate 81 side and relatively increase the amount of reflection on the fixed slit plate 82 side, as shown in FIG. The detection output light quantity is adjusted as shown in FIG. Note that the light amount adjusters 6 may be provided individually, or may be provided on one side and adjusted in accordance with the detection output of the other.

Note that the type of encoder is not limited to the one in the embodiment, but may be one that uses optical fiber, and can be applied to all types of encoders, such as rotary type and linear type, and is configured to obtain multiple detection signals. It may be something.

[Effect of idea]

As explained above, there is a means for adjusting the light intensity of the detection output by reflecting a part of the light transmitted through the rotating slit plate on the detection part side with a reflection rod, so it is separate from the electric circuit part. It is possible to adjust the light intensity of each detection section independently with an extremely simple configuration, and by simply connecting it to the electrical circuit section via an optical fiber connector, it can generate the required rectangular wave according to the characteristics of the electrical circuit section. This has the effect of providing an encoder device in which signals can be easily obtained and both the electric circuit section and the detection section are compatible.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of the optical fiber encoder device of the present invention, FIG. 2 is a side sectional view showing an embodiment of the light amount regulator of the present invention, and FIG. 3 is a characteristic curve diagram showing the detected output light amount. Fig. 4 is a characteristic curve diagram showing a detected electric signal and a rectangular wave signal depending on the detected output light amount, Fig. 5 is an explanatory diagram of the main parts in another embodiment, and Figs. 6 and 7 are before adjustment in Fig. 5. FIG. 8 is a schematic diagram of a conventional optical fiber and encoder device. A is an electric circuit section, B is a detection section, 2 is a light emitting element,
3 and 4 are optical fiber connectors, 51 and 52 are optical fibers, 6 is a light amount adjuster, 7 is a lens, 8 is a fixed slit plate, 9 is a rotating disk, 10 is a light receiver,
61 is a reflecting rod, 62 is a fixed base, and 63 is a rotating threaded rod.

Claims (1)

[Scope of utility model registration request] A light-emitting element, a light-receiving element, and a waveform shaping circuit for processing output signals of the light-receiving element are provided, and an electric circuit section is provided with a receptacle for an optical fiber connector optically connected to the light-emitting element and the light-receiving element, and an electric circuit section is provided between the slit. It is composed of a rotating disk having a reflective surface and a fixed slit plate made of a non-reflecting plate, and a detecting section provided with an optical fiber, one end of which is connected to the plug of the optical fiber connector, and the other end of which is opposed to the fixed slit plate. . A reflective optical fiber encoder device, characterized in that a light amount adjuster for selectively reflecting a part of the light passing through the slit of the rotary disk is provided behind the rotary disk of the detection section.