JPH02148399A - Rotating shaft signal transmitting device - Google Patents

Abstract

PURPOSE:To eliminate the necessity of maintenance from the transmitting device by arranging light receiving elements on a fixed section and rotating section sides on a rotating shaft and light emitting elements on a prescribed circumference around the rotating shaft. CONSTITUTION:This rotating shaft signal transmitting device 1 spatially propagates transmitting signals from a fixed section 2 to a rotating section 3 or from the rotating section 3 to the fixed section 2 as modulated signals. A light receiving element 9 on the fixed section 2 side and a light receiving element 16 on the rotating section 3 side are arranged on the axis X-X of a rotating shaft 18 and light emitting elements 8 and 15 are arranged on a prescribed circumference around the axis X-X of the shaft 18. The central light emitting axes of the elements 8 and 15 are respectively directed to the elements 16 and 9. Therefore, relative positional relation between the elements between the sections 2 and 3 is always fixed irrespective of the rotation of the section 3 and stable signal transmission is performed. When such transmitting device is used, the device can be maintained easily, since no contacting and sliding sections exit on the electric circuit.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention relates to a rotating part that rotates around a rotating shaft and a fixed part in an industrial machine, a robot, or a conveying device. The present invention relates to a rotating shaft signal transmission device that transmits electrical signals between a rotary shaft signal transmission device and a rotating shaft signal transmission device.

(Prior Art) In various industrial machines, robots, transportation equipment, etc., it is often necessary to transmit electrical signals between rotating parts and fixed parts.

In such cases, conventionally, electrical continuity was maintained through sliding contact between the slip ring and the brush, and signal transmission was performed.

(Problems to be Solved by the Invention) However, since there is a mechanical sliding part in the rotary shaft signal transmission device consisting of the slip ring and brush, there are problems such as wear, variation in contact resistance, or deviation in relative positional relationship. There were problems with maintainability and reliability of signal transmission, as noise was generated due to wear and tear.

The present invention has been made to solve the above-mentioned drawbacks of the conventional technology, and by transmitting signals between the rotating part and the fixed part without contact, maintenance-free and highly reliable rotating shaft signal transmission can be achieved. The purpose is to provide a device.

[Structure of the invention]

(Means for Solving the Problems) A rotating shaft signal transmission device of the present invention includes a modulation circuit that modulates a signal to be transmitted to a rotating part at a predetermined frequency, and a light emitting device that emits light in synchronization with the modulation signal from the modulation circuit. a fixed part consisting of an element, a light receiving element that receives an optical signal from the light emitting element installed on the rotating part side, and a demodulation circuit that demodulates the signal from the light receiving element and returns it to the original signal; to the fixed part; A modulation circuit that modulates a signal to be transmitted at a predetermined frequency different from a modulation frequency on the fixed part side, a light emitting element that emits light in synchronization with the modulation signal from the modulation circuit, and a light emitting element installed on the fixed part side. a rotating part comprising a light receiving element that receives an optical signal from the light emitting element; and a demodulation circuit that demodulates the signal from the light receiving element and returns it to the original signal; one of the light receiving element and the light emitting element; are each mounted on the axis of the rotating shaft, and the other light-receiving element and light-emitting element are mounted on a circular orbit in a plane centered on the axis, facing toward the one light-receiving element or light-emitting element. It is characterized by:

(Function) In the rotating shaft signal transmission device of the present invention configured as described above, the transmission signal from the fixed part to the rotating part or from the rotating part to the fixed part is spatially propagated as a modulated optical signal. Further, one of the light receiving element and the light emitting element is mounted on the axis of the rotating shaft, and the other is mounted on a circular orbit of a constant radius off the axis, facing the one light receiving element or the light emitting element. Therefore, the relative positional relationship between the light receiving element and the light emitting element between the fixed part and the rotating part is always constant regardless of the rotation of the rotating part, and stable signal transmission is performed.

Furthermore, since the modulation frequencies are different between the fixed part and the rotating part, there is no mutual interference and signal transmission can be performed in full duplex mode.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the device of the present invention, and a rotating shaft signal transmission device 1 is composed of a fixed portion 2 and a rotating portion 3. As shown in FIG.

The fixed part 2 receives a serial signal Sl from the fixed part control device 4.
A modulation circuit 7 that modulates the on/off of the oscillator 5 with a frequency "l" from the oscillator 5 and a frequency "2" from the oscillator 6, a light emitting element 8 that emits light according to the output signal S2 of this modulation circuit, and a rotating section 3. A light-receiving element 9 receives the light emission signal from the light-receiving element, and the output signal S7 from this light-receiving element is input, detects and demodulates only the frequency 1'3.r4 configuration from the modulated signal from the rotating part 3, and outputs the signal S8. It is composed of a demodulation circuit 10.

The rotating section 3 also controls the on/off of the serial signal S5 from the rotating section control device 11 at the frequency f3 from the oscillator 12.
and a modulation circuit 1 that modulates the frequency f4 from the oscillator 13.
4, a light emitting element 15 that emits light according to the output signal S6 of this modulation circuit, a light receiving element 16 that receives the light emitting signal from the fixed part 2, and an output signal S3 of this light receiving element is input, and the modulation from the fixed part 2 is performed. From the signal, frequency f'1. 11 includes a demodulation circuit 17 that detects and demodulates only the r2 configuration and outputs a signal S4.

Figure 2 shows the serial signals Sl, S4 and the frequency 1'1.
．． , l'2 modulated by the signal S2. It shows the relationship of S3. Although not shown, the signal S5. S
O, S7. The relationship for S8 is also similar to that in Figure 2 (
However, the modulation frequency of the signal SO, S7 is r3. r4)
.

FIG. 3 shows the structural positional relationship between the light emitting element 8° 15 and the light receiving elements 9 and 16 in the embodiment shown in FIG. 9.1
6 are installed respectively.

The light receiving element 9 on the fixed part 2 side and the light receiving element 16 on the rotating part 3 side are arranged on the axis XX of the rotating shaft 18, and the light emitting element 8.15 is arranged on the axis XX of the rotating shaft 18. It is installed on a predetermined circumference around the center.

The light emitting element 8 is arranged with the central axis of emitted light directed toward the light receiving element 16, and the light emitting element 15 is arranged with the central axis of emitted light directed toward the light receiving element 9. Note that 19 indicates a bearing.

Therefore, as shown in FIG. 4, even if the rotating part 3 rotates,
The signal from the light emitting element 15 is always received by the light receiving element 9, and although not shown, the signal from the light emitting element 8 is always received by the light receiving element 16 even when the rotating section 3 rotates.

In the rotating shaft signal transmission device of the present invention configured as described above, when sending a signal from the fixed part 2 to the rotating part 3, the serial signal Sl output from the fixed part control device 4 is as shown in FIG. When the serial signal S1 is off, the frequency r1 of the oscillator 5 is used, and when the serial signal S1 is on, the frequency f2 of the oscillator 6 is modulated by the modulation circuit 7, and the signal S2 is output.

The light emitting element 8 turns on and off light emission in synchronization with the signal S2. Furthermore, upon receiving the light emission signal from the light emitting element 8, the light receiving element 16 of the rotating section 3 outputs an electric signal S3.

When the demodulation circuit 17 manually inputs the signal S3, it detects only the frequency "l" and "r2" components therein, and further removes the modulated wave component to generate a signal S4 having the same waveform as the original serial signal S1.
Output.

Similarly, when sending No. 15 from the rotating part 3 to the fixed part 2, the serial signal S5 output from the rotating part control device 1]
When it is off, the frequency of the oscillator 12 becomes ``3,''
When the serial signal S5 is on, the frequency r4 of the oscillator 13
The signal S6 is modulated by the modulation circuit 14 so that
Output.

The light emitting cord 15 turns on and off the light emission in synchronization with the signal S6. Furthermore, upon receiving the light emission signal from the light emitting element 15, the light receiving element 9 of the fixed part 2 outputs an electric signal S7.

When the demodulation circuit 10 receives the signal S7, it detects only the frequency rl and r2 components therein, and further removes the modulated wave component to produce a signal S8 having the same waveform as the original serial signal S5.
Output.

As shown in FIG. 3, even if the rotating shaft 18 rotates, the rotating part 3
The light-receiving element 16 simply rotates around the light-receiving central axis,
The relative positional relationship between the fixed part 2 and the light emitting element 8 does not change.

Furthermore, as shown in FIG. 4, the light emitting element 5 of the rotating section 3 always moves on a circular orbit perpendicular to the rotating shaft 18 and centered around the rotating shaft 2 on the fixed section 2, as shown in FIG. The light-receiving element 9 of Therefore, the light emitting element 15 and the light receiving element 9
The relative positional relationship between the rotating part 3 and the fixed part 2 does not change, and no matter what angle the rotating part 3 rotates with respect to the fixed part 2, optical signals can always be exchanged at a constant level.

Although FIG. 4 only shows the relative positional relationship between the light receiving element 9 and the modulation circuit 15, the relative positional relationship between the light receiving element 16 and the modulation circuit 8 is also the same as in the case of FIG. This is a matter of course, and therefore, optical signals can be transmitted and received between the fixed part 2 and the rotating part 3 in a duplex manner without causing level fluctuations.

In addition, in FIG. 3, the positions of the light emitting element 8 and the light receiving element 9 of the fixed part 2 are exchanged, and the positions of the light emitting element 1 of the rotating part 3 are changed.
5 and the light-receiving element] Functions in the same manner as above even if the positions of 6 are switched.

As described above, in the case of the present invention, signal transmission between the fixed part and the rotating part can be performed in a full-duplex manner without electrical contact even when the rotating part is rotating.

FIG. 5 shows another embodiment of the present invention, the basic configuration of which is the same as that shown in FIG. It is located at the point surrounded by the blocking plate 21.

In this way, it is possible to prevent signal deterioration due to ambient light, interference due to internally reflected light, and contamination of the lens surfaces of the light emitting element and light receiving element due to intrusion of dust.

〔Effect of the invention〕

As mentioned above, in the rotating shaft signal transmission device of the present invention, there are no contact parts or sliding parts on the electric circuit between the fixed part and the rotating part, so there is no noise generation or wear, and signal transmission is improved. Reliability is improved and maintenance-free operation becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the rotary shaft signal transmission device of the present invention, FIG. 2 is a signal timing chart explaining its operation, and FIG. 3 is a diagram of a light emitting element and a light receiving element in an embodiment of the present invention. FIG. 4 is a perspective view illustrating its operation, and FIG. 5 is a longitudinal sectional view showing another embodiment of the present invention. 1... Rotating shaft signal transmission device, 2... Fixed part, 3...
・Rotating part, 5.6. 12. 13... transmitter, 8,
15... Light emitting element, 9.16... Light receiving element, 20.
...Matte paint, 21...shielding board. hand diagram

Claims (1)

[Claims] A modulation circuit that modulates a signal to be transmitted to the rotating part at a predetermined frequency, a light emitting element that emits light in synchronization with the modulation signal from this modulation circuit, and receiving an optical signal from the light emitting element installed on the rotating part side. a fixed part consisting of a light-receiving element and a demodulation circuit that demodulates the signal from the light-receiving element and returns it to the original signal;
a modulation circuit that modulates a signal to be transmitted to a fixed part at a predetermined frequency different from a modulation frequency on the fixed part side; a light emitting element that emits light in synchronization with the modulation signal from the modulation circuit;
a rotating part comprising: a light receiving element that receives an optical signal from a light emitting element installed on the fixed part side; and a demodulation circuit that demodulates the signal from the light receiving element and returns it to the original signal; and a light-emitting element are each mounted on the axis of the rotating shaft, and the other light-receiving element and light-emitting element are mounted on a circular orbit in a plane centered on the axis. A rotary shaft signal transmission device characterized in that it is installed facing toward.