JP2001099245A - Reduction gear with rotation detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reduction gear with a rotation detector to detect output rotation with high resolution and high-precision and to perform full closed control of a motor with high resolution and high precision. SOLUTION: This reduction gear comprises a code disc 111 having position information corresponding to rotation at the internal part of a reduction gear 100 with a rotation detector; a detecting part 112 for detecting position information of the code disc 111, converting the position information into an electric signal and outputting; and a rotation detector 110 provided with an electronic device 113 to have a function to process the electric signal. Output rotation of a first shaft 130 being an output shaft is detected with high resolution and high-precision by the rotation detector 110. Further, full closed control of a motor 190 is performed with high resolution and high precision by using the reduction gear 100 with a rotation detector together with the motor 190.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed reducer with a rotation detector, and more particularly, to use with a motor and feed back output rotation information to the motor to accurately drive joints of an industrial robot. The present invention relates to a speed reducer with a rotation detector.

[0002]

2. Description of the Related Art Conventionally, FA (Factory Auto)
Various types of reduction gears have been used for precision control of industrial robots, machine tools, indexing boards, and the like in the field of operation. As these reduction gears, for example, there are reduction gears such as Harmonic Drive (registered trademark) reduction gears. The reduction gear is used together with the motor to reduce the rotation of the motor and obtain the drive of an industrial robot or the like. At this time, in order to accurately drive the joints and the like of the industrial robot, a method using a so-called semi-closed control that detects rotation information input from the motor to the speed reducer and controls the rotation of the motor based on the information. Was known.

However, in such a method using semi-closed control, the rotation of the motor is controlled by predicting the output rotation of the reduction gear based on the rotation information input from the motor to the reduction gear. However, in this semi-closed control method, there is a limit to the control accuracy of the rotation of the motor because it is affected by a mechanical error or the like of the speed reduction mechanism.

As one method for solving this problem, Japanese Patent Application Laid-Open No. 8-184349 discloses a method of detecting rotation information output from an eccentric oscillating reduction gear and controlling the rotation of a motor based on the information. A method using so-called fully closed control is disclosed. In the method using this fully closed control, the rotation information output by the eccentric oscillating type speed reducer,
That is, since the rotation of the motor is controlled by the rotation information in the vicinity of the control target, the influence of the mechanical error of the speed reduction mechanism is reduced, and the control accuracy can be improved as compared with the method using the semi-closed control.

[0005]

However, in the method disclosed in Japanese Patent Application Laid-Open No. 8-184349, a means for detecting rotation information output from an eccentric oscillating reduction gear and outputting the information to the outside (hereinafter referred to as a means). , The rotation detector) is composed of a code plate and a sensor, so that the resolution of the rotation detector has to be limited to the resolution of the code plate.

As a technique for improving the resolution of the rotation detector, it is known to use a frequency multiplier that multiplies the frequency of the code plate by processing information output from the rotation detector. The information output from the rotation detector is sent to the frequency multiplier as an electric signal, but the electric signal has a very low voltage level, so that it is susceptible to noise and consequently the accuracy of the rotation detector is reduced.

Therefore, the present invention provides a speed reducer with a rotation detector capable of detecting output rotation with high resolution and high accuracy, and uses the speed reducer with a rotation detector to achieve high resolution and high speed. It is an object to perform full closed control of a motor with high accuracy.

[0008]

In order to solve the above problems, a speed reducer with a rotation detector according to the present invention comprises: an input shaft for inputting rotation; a first shaft having a coaxial relationship with the input shaft; A second axis that is coaxial with one axis and surrounds one end of the first axis to form a space with the first axis, and a first axis and a second axis that are interposed between the first axis and the second axis. A bearing in which the two shafts maintain a coaxial relationship with each other and one is rotatably supported by the other, and the second shaft is decelerated by reducing the rotation input to the input shaft when one of the first shaft and the second shaft is fixed. A deceleration mechanism that outputs to the other of the one axis and the second axis, and detects rotation information of the other of the first and second axes that is interposed in the space formed between the first and second axes. A speed reducer with a rotation detector, comprising: a code plate having position information corresponding to the rotation; and a position information of the code plate. A detector detecting section for outputting changed into electrical signals the location information, characterized by comprising an electronic device, a having an amplification means for amplifying the voltage of the electrical signal detector has outputted. Thus, the voltage level of the electric signal output from the detection unit is amplified by an electronic device near the detection unit, so that the influence of external noise can be reduced, and one of the first and second axes can be reduced. Can be obtained with high accuracy. Therefore, when the speed reducer with a rotation detector of the present invention is used together with a motor, rotation information output from the speed reducer with the rotation detector can be detected, and the rotation of the motor can be controlled with high accuracy based on the information. Become like

Further, the reduction gear with a rotation detector according to claim 2 is the reduction gear with a rotation detector according to claim 1,
The code plate is supported by the first shaft, and the detection unit is supported by the second shaft. Thus, a general code plate having positional information recorded on the outer peripheral surface can be used as the code plate.

According to a third aspect of the present invention, there is provided a speed reducer with a rotation detector according to the first or second aspect, wherein the electronic device multiplies the frequency of an electric signal output from the detection unit by the electronic device. And a multiplying means for performing the operation. Accordingly, the resolution of the rotation detector is not limited to the resolution of the code plate, and a resolution higher than the resolution of the code plate can be realized, and the other rotation information with respect to one of the first axis and the second axis is high. It can be obtained with resolution. Therefore, if the speed reducer with a rotation detector of the present invention is used together with a motor, rotation information output from the speed reducer with a rotation detector can be detected, and the rotation of the motor can be controlled with high resolution based on the information. Become like

According to a fourth aspect of the present invention, there is provided a speed reducer with a rotation detector according to the first or second aspect, wherein the rotation detector includes a plurality of the detection sections, and Is provided with a removing means for removing the influence of the eccentricity of the code plate from the electric signals output from the plurality of detecting units. The reduction gear with a rotation detector has a problem that the first shaft or the second shaft is eccentric. Therefore, there is a possibility that the detection unit does not accurately obtain information on the rotation of one of the first axis and the second axis with respect to the other, and even if the accuracy of the electric signal output from the detection unit is increased, The information about the rotation of one of the axis and the second axis relative to the other may be of low accuracy. Therefore, by providing a plurality of detection units, rotation information without the influence of eccentricity can be obtained from rotation information detected by the detection unit.

According to a fifth aspect of the present invention, there is provided a speed reducer with a rotation detector according to the first or second aspect, wherein the electronic device stores an electric signal output from the detection unit. The signal storage means is provided. Accordingly, when the code plate is of an incremental type, the code plate can be made pseudo-absolute by storing the electric signal output from the detector by the signal storage means.

According to a sixth aspect of the present invention, there is provided a speed reducer with a rotation detector according to the first or second aspect, wherein a seal interposed between the first shaft and the second shaft. Wherein the seal partitions the space formed between the first shaft and the second shaft to prevent foreign matter from adhering to the rotation detector. Thereby, it is possible to prevent iron powder and friction powder mixed in oil in the speed reducer with the rotation detector from adhering to the rotation detector, and to prevent lowering of accuracy and resolution of the rotation detector. Can be.

According to a seventh aspect of the present invention, there is provided a speed reducer with a rotation detector, wherein an input shaft for inputting rotation, a first shaft having a coaxial relationship with the input shaft, and a first shaft having a coaxial relationship with the first shaft. A second axis surrounding one end of one axis to form a space between the first axis and the first axis and the second axis interposed between the first axis and the second axis to maintain a coaxial relationship with each other. A bearing that allows one to be rotatably supported on the other, and when one of the first shaft and the second shaft is fixed, the rotation input to the input shaft is reduced to the other of the first and second shafts. A rotation mechanism having an output deceleration mechanism and a rotation detector interposed in the space formed between the first axis and the second axis and detecting rotation information of the other of the first axis and the second axis. In a speed reducer with a detector, the rotation detector includes a code plate having position information corresponding to rotation, and the code plate has an outer periphery having the position information. And the first shaft is supported by the first shaft, the first shaft has a rolling surface for rolling the bearing, and the rolling surface and the outer peripheral surface of the code plate maintain a coaxial relationship. It is characterized by being formed in. This makes it possible to match the recording center of the position information with the rotation center of the speed reducer with a rotation detector. Therefore, the speed reducer with a rotation detector of the present invention can detect the output rotation with high accuracy.

Further, the reduction gear with a rotation detector according to claim 8 is the reduction gear with a rotation detector according to claim 7,
The code plate and the first shaft are integrally formed. This makes it possible to easily match the recording center of the position information with the rotation center of the speed reducer with the rotation detector. Therefore, the speed reducer with a rotation detector of the present invention can detect the output rotation with high accuracy.

[0016]

Preferred embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment)

An eccentric oscillating speed reducer with a rotation detector according to a first embodiment of the present invention will be described with reference to FIGS.

FIGS. 1 and 2 show an eccentric oscillating reduction gear with a rotation detector according to a first embodiment of the present invention. FIG.
2 is a side sectional view thereof, and FIG. 2 is a sectional view taken along the line AA of FIG. 3 is a plan view of the electronic device according to the first embodiment of the present invention, FIG. 4 is a view similar to FIG. 3, and is a plan view showing another electronic device, and FIG. FIG. 4 is a block diagram of the electronic device shown in FIG.

First, the configuration will be described.

1 and 2, reference numeral 190 denotes a motor. The motor 190 has a motor body 191 for generating rotation and a rotating shaft 19 for outputting the generated rotation to the outside.
And 2.

Reference numeral 100 denotes an eccentric oscillating reduction gear with a rotation detector interposed between the motor 190 and an external member (not shown) for reducing the rotation output by the motor 190 and outputting the reduced rotation to the external member. . Eccentric oscillating reduction gear with rotation detector 1
00 is an input shaft 120 for inputting rotation,
A first shaft 130 coaxial with the first shaft 130 and arranged to surround the input shaft 120; a second shaft 140 coaxial with the first shaft 130 and arranged to surround the first shaft 130; Bearings 151 and 152 interposed between the single shaft 130 and the second shaft 140 so that the first shaft 130 and the second shaft 140 maintain a coaxial relationship with each other so that one is rotatably supported by the other; A speed reduction mechanism 160 that reduces the rotation input to the input shaft 120 when one of the shaft 130 and the second shaft 140 is fixed, and outputs the rotation to the other of the first shaft 130 and the second shaft 140;
A rotation detector 110 interposed between the first shaft 130 and the second shaft 140 for detecting rotation information of the other of the first shaft 130 and the second shaft 140.

Hereinafter, an eccentric oscillating reduction gear 10 with a rotation detector will be described.
0 will be described in detail.

The rotation detector 110 has a cylindrical shape and an incremental type code plate 111 in which position information is magnetically recorded on the outer peripheral surface 111a. The position information of the code plate 111 is detected, and the position information is detected by an electric signal. And an electronic device 113 that processes the electric signal output from the detection unit 112. The code plate 111 is composed of a non-magnetic material, for example, aluminum, and a magnetic material coated on the outer periphery of the non-magnetic material and recorded with positional information. The first shaft 130 is not directly touched.

The input shaft 120 includes an input shaft main body 121, a key 122 mounted inside the input shaft main body 121,
The input shaft 120 is connected to a motor 190
Eccentric oscillating reduction gear with rotation detector 100
To enter. Note that a first spur gear 161 having a predetermined number of teeth is formed at a tip end portion of the input shaft main body 121. The rotation shaft 192 of the motor is operated by the key
1, the input shaft main body 121 is screwed to the tip of the rotation shaft 192 by a nut 181, and the input shaft 120 is fixed to the rotation shaft 192.

The first shaft 130 is fixed to an external member and is arranged at a predetermined interval in the circumferential direction with an output plate 131 for outputting the rotation reduced by the eccentric oscillating reduction gear 100 with the rotation detector to the external member. A first shaft first main body 132 fixed to the output plate 131 by a plurality of bolts 134 and 135, and a plurality of positioning pins 137 arranged at predetermined intervals in a circumferential direction.
And the first shaft second main body 133 fixed to the first shaft first main body 132 by a plurality of bolts 136 arranged at predetermined intervals in the circumferential direction, and the eccentric oscillating speed reducer 100 with a rotation detector. And a partition cover 138 for partitioning the oil in the inside so as not to flow into the rotation detector 110. The first shaft 130 is input from the input shaft 120 and is driven by the eccentric oscillating reduction gear 100 with the rotation detector. The decelerated rotation is output to an external member. Here, the output plate 131 has a plurality of bolt mounting portions 131a and 131b formed on one surface side at predetermined intervals in a circumferential direction.
The external member is fixed by a and 131b.

The second shaft 140 is annular and has an internal gear member 141 having an internal gear 166 formed by a pin on the inner periphery.
And a plurality of bolts 14 arranged at predetermined intervals in the circumferential direction.
The motor 190 is fixed to the internal gear member 141 by the fourth and 145, and is attached to the detection unit attachment member 142 by the plurality of bolts 145 arranged at predetermined intervals in the circumferential direction, and the motor 190 And a motor mounting member 143 for mounting the motor. The detecting section 112 is attached to the detecting section attaching member 142 by bolts 183 so as to keep a predetermined distance from the outer peripheral surface 111a of the code plate 111. The code plate 111 is fixed to the first shaft second main body 133, and rotates together with the first shaft second main body 133. The electronic device 113 is attached to the detection unit attachment member 142 by an electronic device attachment member 184 in addition to the detection unit 112. The motor body 191 of the motor 190 is mounted on the motor mounting member 1 by a plurality of bolts 185 arranged at predetermined intervals in the circumferential direction.
43.

The bearing 151 is interposed between the first shaft first main body 132 and the internal gear member 141, and the bearing 152 is interposed between the first shaft second main body 133 and the internal gear member 141.
The first shaft 130 is rotatably supported by the second shaft 140 by the bearings 151 and 152.

The reduction mechanism 160 includes a first spur gear 161 and
A plurality of second spur gears 162 having a greater number of teeth than the first spur gear 161 are provided around the first spur gear 161 at predetermined intervals in the circumferential direction so as to mesh with the first spur gear 161, and the second spur gear 162 is provided at the end thereof. A plurality of crankshafts 163 having a pair of crank portions 163a mounted so as to maintain the axial relationship, bearings 167A, 167B, 164A and 164B, an internal gear 166, and an internal gear 166 are arranged so as to mesh with the internal gear 166. And a pair of external gears 165A and 165B having a number of teeth slightly smaller than the number of teeth of the speed reducer 160. This reduction mechanism 160 controls the rotation input to the eccentric oscillating reduction gear 100 with a rotation detector. Slow down. In addition,
One ends of the plurality of crankshafts 163 are supported by the first shaft first main body 132 via bearings 164A, and the other end portions of the plurality of crankshafts 163 are supported by the first shaft second main body 133 via bearings 164B. ing. This bearing 164A, 1
64B, the plurality of crankshafts 163
It is supported rotatably. Also, the external gear 165A,
165B are supported by a pair of crank portions 163a of a plurality of crankshafts 163 via bearings 167A and 167B, respectively, and maintain a predetermined eccentricity with respect to the center axis of the internal gear member 141 in accordance with the rotation of the crankshaft 163. Circular motion, that is, a revolving motion having a revolving radius of a predetermined amount of eccentricity.

Reference numerals 171, 172, and 173 denote seals for restricting the flow of oil in the eccentric oscillating reduction gear 100 with a rotation detector. The seal 171 is provided between the first shaft second main body 133 and the motor mounting member 143. The seal 172 is interposed between the first shaft second main body 133 and the detection unit mounting member 142, and the seal 173 is interposed between the first shaft first main body 132 and the internal gear member 141. . That is, the seal 171,
172 and 173 are interposed between the low-speed rotating parts between the first shaft 130 and the second shaft 140.

Hereinafter, the components of the electronic device 113 will be described in detail.

3 to 5, reference numerals 10 and 10 'denote input connectors for inputting an output electric signal from the detection unit 112 to the electronic device 113, and reference numerals 11 and 11' denote amplifier circuits for amplifying the voltage of the electric signal. Reference numeral 12 'denotes an eight-segment circuit for generating eight approximate sinusoidal electric signals whose phases are sequentially shifted by 45 ° based on the approximate A and B sinusoidal electric signals having a phase difference of 90 ° from each other. , 13 'is an 8-divided circuit 1.
A multiplexer circuit for outputting, in a time series manner, eight approximate sine-wave electric signals generated by 2, 2 ';
4 'is a filter circuit for removing unnecessary frequency components from the electric signal, 15 and 15' are comparator circuits for digitizing the electric signal, 16 is a CPU for processing the digitized electric signal, and 18 is a built-in memory. A CPU for processing the digitized electric signal, 17 an output connector for outputting the electric signal processed by the electronic device 113 to the outside, 19 a serial transmission circuit for converting the signal into a serial signal, 20 a backup for storing information Battery.
Here, the amplifier circuits 11 and 11 'constitute amplifying means. The eight-divided circuits 12, 12 ', the multiplexer circuits 13, 13', the filter circuits 14, 14 ', the comparator circuits 15, 15', and the CPUs 16, 18 provide a multiplier for multiplying the frequency of the electric signal output from the detector 112. Means. Also, the amplifier circuits 11, 11 ',
Eight division circuits 12, 12 ', multiplexer circuits 13, 1
3 ′, filter circuits 14 and 14 ′, comparator circuits 15 and 15 ′, and CPUs 16 and 18
A removing means for removing the influence of the eccentricity of the code plate 111 from the electric signal output from the controller 12 is provided. Also, CPU
The battery 18 and the backup battery 20 constitute a signal storage unit that stores the electric signal output from the detection unit 112.

Next, the operation will be described.

First, the operation in which the rotation input from the motor 190 is reduced by the eccentric oscillating reduction gear 100 with the rotation detector and output to the external member will be described.

In FIG. 1, first, rotation is generated by the motor main body 191 of the motor 190. Next, since the rotating shaft 192 and the input shaft 120 are fixed, the rotation is transmitted to the eccentric oscillating type speed reducer 100 with the rotation detector by the input shaft 12.
Input from 0. Next, the rotation input from the input shaft 120 is transmitted to the reduction mechanism 160 from the first spur gear 161 having a predetermined number of teeth formed at the distal end portion of the input shaft main body 121.

The number of teeth of the second spur gear 162 is
1, the rotation transmitted to the speed reduction mechanism 160 is reduced at a predetermined reduction ratio corresponding to the gear ratio between the first spur gear 161 and the second spur gear 162, and the rotation of the plurality of crankshafts 16 is reduced.
3 is transmitted. Next, since the external teeth of the external gears 165A and 165B have slightly fewer teeth than the internal gear 166, the rotation transmitted to the plurality of crankshafts 163 depends on the difference in the number of teeth between the internal gear 166 and the external gears 165A and 165B. Further, the speed is further reduced at the predetermined reduction ratio.

Next, the second shaft 140 and the motor 190 are fixed by the bolt 185 and the first shaft 130 is rotatably supported by the second shaft 140 by the bearings 151 and 152. The rotation is transmitted to the first shaft 130.

Finally, the rotation transmitted to the first shaft 130 is output to an external member fixed to the output plate 131.

As described above, the rotation input from the motor 190 is decelerated by the eccentric oscillating speed reducer 100 with a rotation detector and output to an external member.

Next, the operation of the characteristic portion of the present invention will be described.

In FIG. 1, the code plate 111 has the first shaft 13
0 and the detection unit 112 is mounted on the second shaft 140, so that when the first shaft 130 rotates with respect to the second shaft 140, the code plate 111 also rotates with respect to the detection unit 112. At this time, since the position information is recorded on the outer peripheral surface 111a of the code plate 111 by magnetism, the detecting unit 11
The position information of the code plate 111 detected by 2 is rotation information of the code plate 111, that is, rotation information of the first shaft 130.
The eccentric oscillating reduction gear 100 with a rotation detector is provided with a detection unit 1.
12 (see FIG. 2), the code plate 111 is provided.
The central axis of the code plate 111 and the first axis
It is possible to correct the error caused by the deviation from the rotation axis of the rotation shaft 30 and the mechanical error of the eccentric oscillating reduction gear 100 with the rotation detector. Note that three or more detection units 112 may be provided. In addition, although only one detection unit 112 may be provided, of course, in this case, the detection unit 112 is more easily affected by a mechanical error or the like than when two or more detection units are provided.

The position information of the code plate 111 detected by the detection unit 112 is converted into an electric signal by the detection unit 112 and output to the electronic device 113. The electric signal output to the electronic device 113 is subjected to processing such as amplification of the voltage and frequency multiplication by the electronic device 113, and output to the motor 190 through wiring (not shown). The motor 190 receives this electric signal and determines the rotation to be output to the rotating shaft 192.
As described above, the output rotation can be detected with high resolution and high accuracy by the electronic device 113. The function of the electronic device 113 will be described later.

Also, the first shaft 130 with respect to the second shaft 140
Is rotated, the first shaft second body 13 on which the rotation detector 110 is disposed by the seals 171 and 172.
3. The oil in the eccentric oscillating reduction gear 100 with the rotation detector does not enter the space surrounded by the detection unit mounting member 142, the motor mounting member 143, and the partition cover 138. Therefore, iron powder and abrasion powder mixed in the oil do not adhere to the rotation detector 110, thereby enabling highly accurate position detection. Also, the electronic device 1
Since the eccentric oscillating speed reducer 100 with the rotation detector is arranged in the eccentric oscillating speed reducer 100 with the rotation detector, the size of the eccentric oscillating type speed reducer 100 with the rotation detector can be reduced. Further, by disposing the electronic device 113 near the detection unit 112, it is possible to minimize the influence of the external noise of the electric signal output from the detection unit 112 and the waveform distortion in the transmission path.

The bearings 151 and 1 of the first shaft 130
52, that is, the rolling surfaces 130a and 13
0b and the portion where the code plate 111 is mounted, that is, the code plate mounting surface 130c is formed in a coaxial relationship, so that it can be polished simultaneously while rotating on a common axis.
The outer peripheral surface 111a and the inner peripheral surface 111b of 11 are also formed in a coaxial relationship, so that they can be simultaneously polished while rotating about a common axis. Therefore, the first shaft 130 and the code plate 1
11 and the central axis of the code plate 111 and the first axis 1
30 rotation axes can be matched.

Here, the function of the electronic device 113 will be described with reference to FIG. 1, FIG. 3, FIG. 4, and FIG.

First, the electronic device shown in FIG. 3 according to the first embodiment of the present invention will be described.

In FIG. 3 and FIG.
, An approximate A and B phase sinusoidal electric signal having a phase difference of 90 ° from each other is input from one detection unit 112. Next, the voltage of the input electric signal of the approximate sine wave of the A and B phases is amplified by the amplifier circuit 11. Therefore,
Approximate sine wave electrical signals are less susceptible to external noise. Next, based on the approximate sine wave electric signals of the A and B phases whose voltages have been amplified by the eight-divided circuit 12, eight sine wave electric signals sequentially shifted by 45 ° are generated by an inverting amplifier or the like. Is done. Next, the eight sinusoidal electric signals generated by the multiplexer circuit 13 are sequentially selected and output in time series. The output electric signals are filtered by the filter circuit 14 to remove unnecessary frequency components. Is converted into a digital signal. At this time, a clock signal is sent from the CPU 16 to the multiplexer circuit 13, and when the code plate 111 rotates by one pitch with respect to the detection unit 112, the electric signal converted into a digital signal by the comparator circuit 15 becomes a reference signal in the CPU 16. And a phase difference of 2π occurs. Therefore, the frequency of the code plate 111 can be multiplied by measuring the phase difference. The electric signal from the other detection unit 112 is also supplied to the input connector 10 ', the amplifier circuit 11', the eight-divided circuit 12 ', the multiplexer circuit 13', and the filter circuit 1.
4 ′ and the comparator circuit 15 ′ handle the same as the electric signal from the one detection unit 112. Then, an error caused by a shift between the axis of the code plate 111 and the rotation axis of the first shaft 130 caused by the electric signal from the two detection units 112 when the code plate 111 is attached, and an eccentric oscillating deceleration with a rotation detector. The effect of the machine error of the machine 100 can be corrected. In addition, the output wiring of the electronic device 113 has a total of nine lines including three lines related to the power supply in addition to six signals of the A-phase, the B-phase, the reference signal Z-phase, and their opposite signals.

The opposite signals of the A-phase, B-phase and reference signal Z-phase signals are used to reduce noise during signal transmission.

Next, the electronic device shown in FIG. 4 according to the first embodiment of the present invention will be described.

In FIG. 4, the operation of the electronic device 113 is basically the same as that of the above-described electronic device 113 shown in FIG. Electric signal to backup battery 20
Is stored in the built-in memory of the CPU 18. At this time,
The CPU 18 and the backup battery 20 form a signal storage unit. The electrical signal converted into the absolute value is transmitted as serial data by the serial transmission circuit 19. Since the position information detected by the detection unit 112 by the signal storage means is stored in the built-in memory of the CPU 18, the rotation detector 110 can be set to the absolute type by the electronic device 113 using the incremental type code plate 111. it can. Therefore, if the electronic device 113 is used, the operation of returning the code plate 111 to the origin is unnecessary. In addition, the number of output wirings of the electronic device 113 is three in total, in addition to the signal lines of the serial data signal and the opposite signal, and three lines related to the power supply.

It should be noted that a signal opposite to the electrical signal of the serial data is used to reduce noise during signal transmission.

The number of output wirings can be reduced by making the electronic device 113 an absolute type.

(Second Embodiment)

An eccentric oscillating speed reducer according to a second embodiment of the present invention will be described with reference to FIGS.

FIGS. 6 and 7 show an eccentric oscillating reduction gear with a rotation detector according to a second embodiment of the present invention. FIG.
7 is a side sectional view thereof, and FIG. 7 is a sectional view taken along line BB of FIG.

First, the configuration will be described.

6 and 7, reference numeral 290 denotes a motor. The motor 290 has a motor body 291 for generating rotation and a rotating shaft 29 for outputting the generated rotation to the outside.
And 2.

Reference numeral 200 denotes an eccentric oscillating reduction gear with a rotation detector interposed between the motor 290 and an external member (not shown) for reducing the rotation output by the motor 290 and outputting the reduced rotation to the external member. . Eccentric oscillating reduction gear with rotation detector 2
00 is an input shaft 220 for inputting rotation, and an input shaft 220
A first shaft 230 coaxial with the first shaft 230 and arranged to surround the input shaft 220; a second shaft 240 coaxial with the first shaft 230 and arranged to surround the first shaft 230; Bearings 251 and 252 interposed between the single shaft 230 and the second shaft 240 so that the first shaft 230 and the second shaft 240 maintain a coaxial relationship with each other and one is rotatably supported by the other; A speed reduction mechanism 260 that reduces the rotation input to the input shaft 220 when one of the shaft 230 and the second shaft 240 is fixed, and outputs the rotation to the other of the first shaft 230 and the second shaft 240;
And a rotation detector 210 interposed between the first shaft 230 and the second shaft 240 and detecting rotation information of the other of the first shaft 230 and the second shaft 240.

Hereinafter, an eccentric oscillating type speed reducer 20 with a rotation detector will be described.
0 will be described in detail.

The rotation detector 210 is an incremental type code plate 211 which has a cylindrical shape and magnetically records position information on an outer peripheral surface 211a, and detects position information of the code plate 211 and converts the position information to an electric signal. And an electronic device 213 that processes the electric signal output from the detection unit 212. The code plate 211 is composed of a non-magnetic material, for example, aluminum and a magnetic material coated on the outer periphery of the non-magnetic material and recording the position information. The first shaft 230 is not directly touched.

The input shaft 220 inputs the rotation output from the motor 290 to the eccentric oscillating reduction gear 200 with a rotation detector.
The input shaft 220 is fixed to the tip of the rotating shaft 292 by screwing with a nut 281.

The first shaft 230 is fixed to an external member and outputs the rotation reduced by the eccentric oscillating reducer 200 with a rotation detector to the external member at a predetermined interval in the circumferential direction. Second output plate 231 fixed to first output plate 231A by a plurality of bolts 234, 235 arranged
B and a plurality of bolts 2 arranged at predetermined intervals in the circumferential direction.
The first shaft first main body 232 fixed to the second output plate 231B by 35 and 239, and the first shaft first main body 23 by a plurality of positioning pins 237 arranged at predetermined intervals in the circumferential direction.
2, a first shaft second body 233 fixed to the first shaft first body 232 by a plurality of bolts 236 arranged at predetermined intervals in a circumferential direction, and an eccentric oscillating reduction gear with a rotation detector. And a partition lid 238 for partitioning the oil inside 200 so as not to flow into the rotation detector 210 side.
The first shaft 230 outputs the rotation that is input from the input shaft 220 and is reduced in speed by the eccentric oscillating reduction gear 200 with the rotation detector. Here, the first output plate 231A has a plurality of bolt attachment portions 231 formed on the other surface side at predetermined intervals in the circumferential direction.
a, 231b, and the bolt mounting portions 231a, 23
1b fixes the external member. A code plate 211 is attached to the first shaft first main body 232 by bolts 282.

The second shaft 240 is fixed to the detector mounting member 241 by a detector mounting member 241 for mounting the detector 212 and a plurality of bolts 244 and 245 arranged at predetermined intervals in the circumferential direction, and has an annular shape. An internal gear member 242 having an internal gear 266 formed by a pin on the inner periphery, and a motor mounting member 243 which is fixed to the internal gear member 242 by a plurality of bolts 245 arranged at predetermined intervals in a circumferential direction and to which a motor 290 is attached. And is composed of In addition,
The detector 212 is attached to the detector mounting member 24 by bolts 283 so as to keep a predetermined distance from the outer peripheral surface 211a of the code plate 211.
It is attached to 1. The code plate 211 is fixed to the first shaft first main body 232, and rotates together with the first shaft first main body 232. In addition, the detection unit mounting member 24
An electronic device 213 is attached to 1 by an electronic device attachment member 284 in addition to the detection unit 212. Further, the motor main body 291 of the motor 290 is fixed to the motor mounting member 243 by a plurality of bolts 285 arranged at predetermined intervals in the circumferential direction.
Attached to.

The bearing 251 is interposed between the first shaft first main body 232 and the internal gear member 242, and the bearing 252 is interposed between the first shaft second main body 233 and the internal gear member 242.
The first shaft 230 is rotatably supported by the second shaft 240 by the bearings 251 and 252.

The reduction mechanism 260 includes a first spur gear 261 and
A plurality of second spur gears 262 having a larger number of teeth than the first spur gear 261 are provided around the first spur gear 261 at predetermined intervals in the circumferential direction so as to mesh with the first spur gear 261, and each of the second spur gear 262 has a tip. A plurality of crankshafts 263 having a pair of crank portions 263a mounted so as to maintain the axial relationship, bearings 267A, 267B, 264A and 264B, an internal gear 266, and an internal gear 266 arranged on the outer periphery so as to mesh with the internal gear 266. And a pair of external gears 265A and 265B having a number of teeth slightly smaller than the number of teeth of the gear. This reduction mechanism 260 controls the rotation input to the eccentric oscillating reduction gear 200 with a rotation detector. Slow down. In addition,
One end of the plurality of crankshafts 263 is supported by the first shaft first main body 232 via the bearing 264A, and the other end of the plurality of crankshafts 263 is supported by the first shaft second main body 233 via the bearing 264B. ing. This bearing 264A, 2
64B, the plurality of crankshafts 263 are
It is supported rotatably. Also, the external gear 265A,
265B are supported by a pair of crank portions 263a of a plurality of crankshafts 263 via bearings 267A and 267B, respectively, and maintain a predetermined amount of eccentricity with respect to the center axis of the internal gear member 242 according to the rotation of the crankshaft 263. Circular motion, that is, a revolving motion having a revolving radius of a predetermined amount of eccentricity.

Incidentally, 271, 272, 273 and 274
Is a seal for restricting the flow of oil in the eccentric oscillating reduction gear with rotation detector 200, a seal 271 is provided between the first shaft second main body 233 and the internal gear member 242, and a seal 272 is provided for the first shaft Between the first main body 232 and the internal gear member 242, a seal 273 is provided between the detection unit mounting member 241 and the second output plate 231B.
The seal 274 is interposed between the first shaft first main body 232 and the second output plate 231B. That is, the seals 271, 272, and 273 are
And the second shaft 240 between the low-speed rotating parts.

Next, the operation will be described.

First, the rotation input from the motor 290 is reduced by the eccentric oscillating reduction gear 200 with the rotation detector and output to the external member in the same manner as in the first embodiment.

Next, the operation of the characteristic portion of the present invention will be described.

In FIG. 6, the code plate 211 is the first shaft 23
0 and the detection unit 212 is mounted on the second shaft 240, so that when the first shaft 230 rotates with respect to the second shaft 240, the code plate 211 also rotates with respect to the detection unit 212. At this time, since the position information is recorded on the outer peripheral surface 211a of the code plate 211 by magnetism, the detecting unit 21
The position information of the code plate 211 detected by 2 is rotation information of the code plate 211, that is, rotation information of the first shaft 230.
The eccentric oscillating reduction gear 200 with a rotation detector is provided with a detection unit 2.
12 (see FIG. 7), the code plate 211 is provided.
Of the code plate 211 and the first shaft 230 generated when the
And the mechanical error of the eccentric oscillating reduction gear with a rotation detector 200 can be corrected.

The position information of the code plate 211 detected by the detection unit 212 is converted into an electric signal by the detection unit 212 and output to the electronic device 213. The electric signal output to the electronic device 213 is subjected to processing such as amplification of the voltage and frequency multiplication by the electronic device 213, and is output to the motor 290 by a wiring (not shown). The motor 290 receives this electric signal and determines the rotation to be output to the rotating shaft 292.
By providing the electronic device 213, the output rotation can be detected with high resolution and high accuracy.

The function of the electronic device 213 is the same as the function of the electronic device 113 of the first embodiment.

Also, the first shaft 230 is
Is rotated, the first shaft first main body 23 on which the rotation detector 210 is disposed by the seals 272 and 273.
2. The oil in the eccentric oscillating speed reducer 200 with the rotation detector does not enter the space surrounded by the second output plate 231B, the detection unit mounting member 241 and the partition cover 238. Therefore, iron powder and abrasion powder mixed in the oil do not adhere to the rotation detector 210, and high-accuracy position detection becomes possible. Also, the electronic device 2
Since the eccentric oscillating speed reducer 200 with the rotation detector is arranged in the eccentric oscillating speed reducer 200 with the rotation detector, the eccentric oscillating type speed reducer 200 with the rotation detector can be downsized. Further, the electronic device is connected to the detection unit 212.
, It is possible to minimize the influence of external noise on the electric signal output from the detection unit 212 and the waveform distortion in the transmission path.

The bearings 251 and 2 of the first shaft 230
52, that is, the rolling surfaces 230a and 23
0b and the portion where the code plate 211 is mounted, that is, the code plate mounting surface 230c is formed in a coaxial relationship, so that it can be polished simultaneously while rotating on a common axis.
The outer peripheral surface 211a and the inner peripheral surface 211b of 11 are also formed in a coaxial relationship, so that they can be simultaneously polished while rotating about a common axis. Therefore, the first shaft 230 and the code plate 2
11 and the central axis of the code plate 211 and the first axis 2
30 rotation axes can be matched.

(Third Embodiment)

An eccentric oscillating speed reducer with a rotation detector according to a third embodiment of the present invention will be described with reference to FIG. The eccentric oscillating reduction gear with a rotation detector according to the present embodiment has substantially the same configuration and operation as the eccentric oscillating reduction gear with a rotation detector according to each of the above-described embodiments. A detailed description of substantially the same configuration and operation as the eccentric oscillating reduction gear with a rotation detector according to the embodiment will be omitted.

First, the configuration will be described.

In FIG. 8, an eccentric oscillating reduction gear 300 with a rotation detector has an input shaft 320 for inputting rotation, and a first coaxial relationship with the input shaft 320 and arranged so as to surround the input shaft 320. An axis 330, a second axis 340 coaxial with the first axis 330 and arranged to surround the first axis 330,
The first shaft 330 interposed between the first shaft 330 and the second shaft 340
Bearings 351 and 352 that maintain the shaft and the second shaft 340 in a coaxial relationship with each other and rotatably support one on the other.
When one of the first shaft 330 and the second shaft 340 is fixed, the rotation input to the input shaft 320 is reduced to reduce the rotation of the first shaft 330.
And a speed reduction mechanism 360 that outputs to the other of the second shaft 340 and rotation detection that is interposed between the first shaft 330 and the second shaft 340 and detects rotation information of the other of the first shaft 330 and the second shaft 340. 310.

The rotation detector 310 includes an incremental type code plate 311 having a cylindrical shape and recording position information by magnetism on an outer peripheral surface 311 a, and a code plate 311.
And an electronic device 313 that processes the electric signal output by the detecting unit 312 by detecting the position information of the electronic device and converting the position information into an electric signal and outputting the electric signal. The code plate 311 is composed of a non-magnetic material, for example, aluminum, and a magnetic material coated on the outer periphery of the non-magnetic material and recording the position information. The first shaft 330 is not directly touched.

Further, the first shaft 330 is fixed to an external member, and an output plate 331 for outputting the rotation reduced by the eccentric oscillating speed reducer 300 with a rotation detector to the external member, a first shaft first main body 332, The first shaft 330 outputs the rotation input from the input shaft 320 and reduced by the eccentric oscillating speed reducer 300 with the rotation detector to an external member.

The second shaft 340 is formed from an inner gear member 341 having an annular shape and an inner gear formed by a pin on the inner periphery, a detecting portion mounting member 342 for mounting the detecting portion 312, and a motor mounting member 343 for mounting a motor. It is configured. The detecting unit 312 is provided on the outer peripheral surface 311 of the code plate 311.
It is attached to the detection unit attachment member 342 so as to keep a predetermined distance from “a”. The code plate 311 is a first shaft second body 333.
, And rotates together with the first shaft second main body 333. An electronic device 313 is attached to the detection unit attachment member 342 in addition to the detection unit 312.

Incidentally, 371, 372, 373 and 374
A seal 371 is provided between the input shaft 320 and the motor mounting member 343, and a seal 372 is provided between the first shaft and the second main body 333. Seal 373 between the
The seal 374 is interposed between the first shaft second main body 333 and the internal gear member 341, respectively, and the seal 374 is interposed between the first shaft first main body 332 and the internal gear member 341. That is, the seals 373 and 374 are interposed between the low-speed rotating parts between the first shaft 330 and the second shaft 340.

Next, the operation will be described.

In the eccentric oscillating reduction gear 300 with a rotation detector, the code plate 311 is composed of a non-magnetic material and a magnetic material coated on the outer periphery of the non-magnetic material and recorded with positional information. The magnetic body on which the position information is recorded is the first shaft 33
It is designed not to touch 0 directly.

The code plate 311 uses an aluminum foil-like thin plate ring as a nonmagnetic material, so that the cost can be reduced.

The code plate 311 can be manufactured, for example, as follows.

First, a ring-shaped non-magnetic material is press-fitted into the first shaft 330. Next, a magnetic material is applied to the outer periphery of the press-fitted nonmagnetic material. Next, the rolling surfaces 330a and 330b of the first shaft 330 for rolling the bearings 351 and 352 and the magnetic material applied to the outer periphery of the non-magnetic material are simultaneously polished while rotating the first shaft 330. Finally, position information is recorded on the magnetic material applied to the outer periphery of the non-magnetic material. Here, the non-magnetic material may be engaged with the first shaft 330 by a method other than press fitting as long as the magnetic material does not directly touch the first shaft 330. For example, a non-magnetic material may be applied or cast to engage the first shaft 330.

As described above, by manufacturing the code plate 311, the rolling surfaces 330 a and 330 b of the first shaft 330 for rolling the bearings 351 and 352 and the outer peripheral surface 311 a of the code plate 311 are separated. It is formed so as to maintain a coaxial relationship.

(Fourth Embodiment)

An eccentric oscillating speed reducer with a rotation detector according to a fourth embodiment of the present invention will be described with reference to FIG. The eccentric oscillating reduction gear with a rotation detector according to the present embodiment has substantially the same configuration and operation as the eccentric oscillating reduction gear with a rotation detector according to the third embodiment. A detailed description of the same configuration and operation as those of the eccentric oscillating reduction gear with a rotation detector according to the above is omitted.

In FIG. 9, in the eccentric oscillating reduction gear 400 with a rotation detector, the code plate 411 has a first shaft second main body 433.
Except for being formed integrally with the eccentric oscillating speed reducer with a rotation detector according to the third embodiment, except that the speed reducer is integrally formed.

In this case, the first shaft second main body 433 is a non-magnetic material.

The code plate 411 can be manufactured, for example, as follows.

First, the first shaft second main body 43 of the first shaft 330
A magnetic material is applied to the outer peripheral surface 433a of the third. Next, the rolling surface 3 of the first shaft 330 for rolling the bearings 351 and 352
30a and 330b and outer peripheral surface 4 of first shaft second body 433
The magnetic material applied to 33a is simultaneously polished while rotating the first shaft 330. Finally, the first shaft second body 433
The positional information is recorded on the magnetic material applied to the outer peripheral surface 433a of the magnetic recording medium.

As described above, when the code plate 411 is manufactured, the rolling surfaces 330a and 330b of the first shaft 330 for rolling the bearings 351 and 352 and the outer peripheral surface 411a of the code plate 411 are separated. It is formed so as to maintain a coaxial relationship.

In each of the above embodiments, the second shaft is fixed to the motor, and the rotation from the motor reduced by the reduction mechanism is output from the first shaft to an external member. The present invention can achieve the same effect even when one shaft is fixed to the motor and the rotation from the motor reduced by the reduction mechanism is output from the second shaft to the external member.

[0097]

According to the present invention, it is possible to obtain a speed reducer with a rotation detector capable of detecting output rotation with high resolution and high accuracy. In addition, by using the speed reducer with the rotation detector, it becomes possible to perform full closed control of the motor with high resolution and high accuracy.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an eccentric oscillating reduction gear with a rotation detector according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a plan view of the electronic device according to the first embodiment of the present invention.

FIG. 4 is a plan view similar to FIG. 3, but showing another electronic device.

FIG. 5 is a block diagram of the electronic device shown in FIG. 3;

FIG. 6 is a side sectional view of an eccentric oscillating reduction gear with a rotation detector according to a second embodiment of the present invention.

FIG. 7 is a sectional view taken along the line BB of FIG. 6;

FIG. 8 is a side sectional view of an eccentric oscillating reduction gear with a rotation detector according to a third embodiment of the present invention.

FIG. 9 is a side sectional view of an eccentric oscillating reduction gear with a rotation detector according to a fourth embodiment of the present invention.

[Explanation of symbols]

11, 11 'amplifier circuit (amplifying means, removing means) 12, 12' 8-divided circuit (multiplying means, removing means) 13, 13 'multiplexer circuit (multiplying means, removing means) 14, 14' filter circuit (multiplying means, Removal means) 15, 15 'comparator circuit (multiplication means, removal means) 16 CPU (multiplication means, removal means) 18 CPU (multiplication means, removal means, signal storage means) 20 backup battery (signal storage means) 100, 200, 300, 400 Eccentric oscillating reduction gear with rotation detector (reduction gear with rotation detector) 110, 210, 310 Rotation detector 111, 211, 311, 411 Code plate 112, 212, 312 Detection unit 113, 213, 313 Electronic device 120, 220, 320 Input shaft 130, 230, 330 First shaft 140, 240, 340 Second shaft 1 1,152,251,252,351,352
Bearing 160, 260, 360 Reduction mechanism 171, 172, 272, 273, 372, 373
Seals 111a, 211a, 311a, 411a Outer peripheral surfaces 130a, 130b, 230a, 230b, 330a,
330b rolling surface

Claims (8)

[Claims] An input shaft for inputting rotation, a first shaft coaxial with the input shaft, and a first shaft coaxial with the first shaft and surrounding one end of the first shaft. A second axis that forms a space in
A bearing interposed between the first shaft and the second shaft so that the first shaft and the second shaft keep a coaxial relationship with each other and one is rotatably supported by the other, and the first shaft and the second shaft When one is fixed, a speed reduction mechanism that reduces the rotation input to the input shaft and outputs the reduced rotation to the other of the first shaft and the second shaft, and intervenes in the space formed between the first shaft and the second shaft A rotation detector that detects the other rotation information for one of the first axis and the second axis, and a reduction gear with a rotation detector, wherein the rotation detector has a code plate having position information corresponding to rotation. A detection unit for detecting position information of the code plate, converting the position information into an electric signal and outputting the electric signal, and an electronic device having an amplifying unit for amplifying a voltage of the electric signal output by the detection unit. Speed reducer with a rotation detector. 2. The speed reducer with a rotation detector according to claim 1, wherein the code plate is supported by the first shaft, and the detection unit is supported by the second shaft. 3. The speed reducer with a rotation detector according to claim 1, wherein the electronic device includes a multiplying means for multiplying the frequency of the electric signal output from the detecting section. 4. The rotation detector includes a plurality of the detection units,
The speed reducer with a rotation detector according to claim 1, wherein the electronic device includes a removing unit configured to remove an influence of the eccentricity of the code plate from the electric signals output from the plurality of detection units. . 5. The speed reducer with a rotation detector according to claim 1, wherein the electronic device includes signal storage means for storing an electric signal output from the detection unit. 6. A seal interposed between said first shaft and said second shaft, said seal partitioning said space formed between said first shaft and said second shaft to prevent foreign matter from entering said rotation detector. The reduction gear with a rotation detector according to claim 1 or 2, wherein the reduction gear is prevented from being attached. 7. An input shaft for inputting rotation, a first shaft coaxial with the input shaft, and a first shaft coaxial with the first shaft and surrounding one end of the first shaft. A second axis that forms a space in
A bearing interposed between the first shaft and the second shaft so that the first shaft and the second shaft keep a coaxial relationship with each other and one is rotatably supported by the other, and the first shaft and the second shaft When one is fixed, a speed reduction mechanism that reduces the rotation input to the input shaft and outputs the reduced rotation to the other of the first shaft and the second shaft, and intervenes in the space formed between the first shaft and the second shaft A rotation detector for detecting the other rotation information for one of the first axis and the second axis, and a reduction gear with a rotation detector, wherein the rotation detector has a code plate having position information corresponding to the rotation. The code plate is formed with an outer peripheral surface having the position information, and is supported by the first shaft. The first shaft has a rolling surface for rolling the bearing, the rolling surface, A reduction gear with a rotation detector, wherein the outer peripheral surface of the code plate is formed so as to maintain a coaxial relationship. 8. The speed reducer with a rotation detector according to claim 7, wherein said code plate and said first shaft are formed integrally.