JP5998682B2 - Encoder, code plate, drive device, and robot device - Google Patents

Description

  The present invention relates to an encoder, a code plate, a drive device, and a robot apparatus.

  An encoder is known as a device that detects position information of a driven body such as a rotating body connected to a rotating shaft of a motor. In such an encoder, for example, a comparator detects a pattern indicating position information of a driven body by a sensor unit including a detection element such as a magnetic sensor, and the comparator compares it with a predetermined fixed threshold voltage. The detection signal is converted into a binarized signal, and position information is detected based on the binarized signal (see, for example, Patent Document 1). In such an encoder, the threshold voltage that is a reference voltage in the comparison of the comparator is generated by, for example, resistance voltage division.

JP 2009-109250 A

However, in the encoder described above, for example, the level of the detection signal detected by the sensor unit varies depending on the detection element, and the binarized signal is generated based on a predetermined fixed threshold voltage. Therefore, for example, when a disturbance such as noise occurs, the encoder described above may cause the detection signal to change across the above-described fixed threshold voltage due to the disturbance and erroneously detect the position information of the driven body. is there.
Thus, the encoder as described above may erroneously detect the position information of the driven body.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an encoder, a code plate, a drive device, and a robot device that can improve reliability.

In order to solve the above problem, an embodiment of the present invention shows a light source unit that emits irradiation light, position information of a driven body, and a reverse phase in which the first light amount and the first light amount are reversed. in response to the first amount of light produced and the code plate, the illumination light through the pattern having a second pattern which causes the amount of light to the irradiation light becomes, the outputs of the first detection signal One light-receiving sensor unit, a second light-receiving sensor unit that outputs a second detection signal according to the second light amount generated in the irradiation light through the pattern, the first detection signal, and Using the second detection signal as a differential signal, a binarization unit that generates a binarization signal corresponding to the position information, and a position detection unit that detects the position information based on the binarization signal; it is an encoder with a.

In addition, according to an embodiment of the present invention, the position information of the driven body is shown, and the first light amount and the second light amount that has the opposite phase obtained by inverting the first light amount are emitted from the light source unit. it is a sign-board with a pattern that causes the light.

  An embodiment of the present invention includes a driven body, a drive unit that moves the driven body, and the encoder described above that is fixed to the driven body and detects position information of the driven body. It is provided with the following.

  Moreover, one Embodiment of this invention is a robot apparatus characterized by including the drive device as described above.

  According to the present invention, reliability can be improved.

It is a schematic block diagram which shows an example of a structure of the encoder by 1st Embodiment. It is a block diagram which shows an example of the encoder in 1st Embodiment. It is a figure which shows an example of operation | movement of the encoder in 1st Embodiment. It is a schematic block diagram which shows an example of a structure of the encoder by 2nd Embodiment. It is a figure which shows an example of operation | movement of the encoder in 2nd Embodiment. It is a schematic block diagram which shows an example of a structure of the encoder by 3rd Embodiment. It is a figure which shows an example of operation | movement of the encoder in 3rd Embodiment. It is a schematic block diagram which shows an example of a structure of the encoder by 4th Embodiment. It is a figure which shows an example of operation | movement of the encoder in 4th Embodiment. It is a schematic block diagram which shows an example of a structure of the encoder by 5th Embodiment. It is a block diagram which shows an example of the encoder in 5th Embodiment. It is a figure which shows an example of the operation | movement of the encoder in 5th Embodiment. It is the schematic of the drive device in this embodiment. It is the schematic of the robot placement in this embodiment. It is a figure which shows the modification of the encoder by 1st Embodiment. It is a figure which shows the modification of the encoder by 5th Embodiment.

Hereinafter, an encoder according to an embodiment of the present invention will be described with reference to the drawings.
[First Embodiment]
In this embodiment, an optical rotary encoder will be described as an example.
FIG. 1 is a schematic configuration diagram showing an example of the configuration of the encoder 1 according to the first embodiment.
In FIG. 1, an encoder 1 includes substrates (5, 7) and a rotor 6 coupled to a code plate 2 (disk). The encoder 1 detects position information (for example, angular position information) of the rotor 6 (driven body).
Here, FIG. 1A shows the configuration of the encoder 1 viewed from the rotational axis direction (Z-axis direction) of the rotor 6, and FIGS. 1B and 1C are viewed from the Y-axis direction. The arrangement of the code plate 2 and the substrates (5, 7) is shown.

  As shown in FIG. 1, the code plate 2 is movable (e.g., rotatable) relative to a light receiving sensor section described later. The code plate 2 is a disk coupled to the rotor 6 and includes, for example, a pattern 20 formed by one track. The substrate 7 includes at least the light source unit 3 and the light receiving element 421, and the substrate 5 includes at least the light receiving element 411.

  The light source unit 3 is a light emitting element such as a laser diode that emits laser light, and emits irradiation light. The light source unit 3 is mounted on the substrate 7 and irradiates the pattern 20 with irradiation light. The light source unit 3 is arranged at a position away from the pattern 20 in the lateral direction of the pattern 20, which is different from the longitudinal direction of the pattern 20, which is the position information detection direction. Here, the position information detection direction (longitudinal direction) is the circumferential direction of the code plate 2, and corresponds to the Y-axis direction in the example of FIG. 1. The short direction is the radial direction of the code plate 2 and corresponds to the X-axis direction in the example of FIG. For example, the light source unit 3 emits irradiation light obliquely from the lateral direction with respect to the pattern 20. Here, for example, the light source unit 3 emits irradiation light at an angle θ in the X-axis direction (short direction) with respect to the vertical plane (ZY plane) of the code plate 2.

  The pattern 20 indicates the position information of the rotor 6, and generates a first light amount, which will be described later, and a second light amount obtained by inverting the first light amount in the irradiation light emitted from the light source unit 3. The pattern 20 is, for example, an absolute pattern that indicates an absolute position by an M (M) series, and includes a transmission unit 20T that transmits the irradiation light (see FIG. 1B) and a reflection unit 20R that reflects the irradiation light (FIG. 1). (See (c)).

  The pattern 20 is formed, for example, by forming a transmission part 20T showing the M series on the code plate 2 by etching and forming a reflection surface 2R on the remaining part. The reflective surface 2R (reflective portion 20R) may be formed by vapor deposition of aluminum or the like, for example, or may be formed by performing mirror surface processing (processing to polish the mirror surface) by cutting. In the present embodiment, for example, the pattern 20 is formed so as to indicate absolute position information by combining the transmissive portion 20T and the reflective portion 20R in one track.

The substrate 7 and the substrate 5 are disposed with the code plate 2 interposed therebetween so that the light emitting surface of the light source unit 3 of the substrate 7 and the light receiving surface of the light receiving element 421 are opposed to the light receiving surface of the light receiving element 411 of the substrate 5. Yes.
In addition, as shown in FIG. 1B, the light receiving element 411 is disposed at a position where the irradiation light emitted by the light source unit 3 receives the irradiation light L <b> 1 transmitted through the transmission unit 20 </ b> T of the pattern 20. For example, the light receiving element 411 is disposed at a position where the irradiation light L1 emitted from the light source unit 3 is incident through the pattern 20 (transmission unit 20T). For example, the irradiation light L1 is incident on the light receiving element 411 at an angle θ in the X-axis direction (short direction) with respect to the vertical plane (ZY plane) of the code plate 2. Here, the light amount including the irradiation light L1 received by the light receiving element 411 corresponds to the first light amount. The first light amount includes a light amount in a predetermined area, for example, includes at least a light amount in the measurement direction in the light receiving region of the light receiving element 411.

  In addition, as shown in FIG. 1C, the light receiving element 421 is disposed at a position where the irradiation light emitted by the light source unit 3 receives the irradiation light L <b> 2 reflected by the reflection unit 20 </ b> R of the pattern 20. For example, the light receiving element 421 is disposed at a position where the irradiation light L2 emitted from the light source unit 3 is incident via the pattern 20 (reflection unit 20R). For example, irradiation light L2 is incident on the light receiving element 421 at an angle θ in the X-axis direction (short direction) with respect to the vertical plane (ZY plane) of the code plate 2. Here, the light amount including the irradiation light L2 received by the light receiving element 421 corresponds to the second light amount. The second light amount includes a light amount in a predetermined region, for example, includes at least a light amount in the measurement direction in the light receiving region of the light receiving element 421.

1B shows an example where the rotational position of the rotor 6 is at the position of the transmission part 20T of the pattern 20, and FIG. 1C shows the reflection position of the pattern 20 when the rotational position of the rotor 6 is. An example in the case of the position of the part 20R is shown.
Here, in the state of FIG. 1B, the first light amount described above increases and the second light amount decreases. Moreover, in the state of FIG.1 (c), the 1st light quantity mentioned above reduces and the 2nd light quantity increases. As described above, the first light amount and the second light amount are in a mutually inverted relationship (reverse phase relationship). Note that the inversion of the light amount includes, for example, inversion of change in the light amount, inversion of the light intensity distribution, and the like. That is, the change in the first light amount and the change in the second light amount are in a mutually inverted relationship. Further, the reversal of the light amount may be a relationship that is completely reversed from each other, or may be a relationship that is substantially reversed from each other.

FIG. 2 is a block diagram illustrating an example of the encoder 1 in the present embodiment.
In FIG. 2, the encoder 1 includes a light source unit 3, a position detection unit 40, a light reception sensor unit 41, a light reception sensor unit 42, and a binarization unit 60.

  The light receiving sensor unit 41 (first sensor unit) detects the pattern 20 and outputs a detection signal ABS (first detection signal) according to the first light amount generated in the irradiation light via the pattern 20. . For example, the light receiving sensor unit 41 outputs the detection signal ABS according to the first light amount generated in the light transmitted through the pattern 20. That is, the light receiving sensor unit 41 outputs the detection signal ABS based on, for example, a change in the irradiation light L1 that has passed through the transmission unit 20T of the pattern 20.

In addition, the light receiving sensor unit 41 includes a light receiving element 411, a power supply unit 412, a resistor 413, and an amplifier unit 414. The light receiving sensor unit 41 includes a plurality of light receiving elements 411 in order to detect a plurality of bits of the M-sequence pattern in parallel, but here, for the sake of explanation, a light receiving detection element group (a plurality of light receiving elements) is provided. One of the elements 411) will be described. The plurality of light receiving elements 411 may be used by switching in time series, for example, and may detect the M series pattern in the pattern 20.
As described above, the light receiving sensor unit 41 (light receiving element 411) is arranged at a position where the irradiation light emitted from the light source unit 3 is incident through the pattern 20.

  The light receiving element 411 (detection element) is, for example, a photodiode, and the current (photocurrent) changes according to the first light quantity (change in the first light quantity) transmitted through the transmission part 20T of the pattern 20. For example, the light receiving element 411 has a cathode terminal connected to the power supply unit 412 and an anode terminal connected to the node N1.

The power supply unit 412 is a power supply circuit that supplies a reverse bias to the light receiving element 411.
The resistor 413 is, for example, a resistive element having a predetermined resistance value, and one end is grounded (connected to the ground line) and the other end is connected to the node N1. The resistor 413 converts a change in current by the light receiving element 411 according to a change in the first light amount into a change in voltage.

  The amplifier unit 414 is an amplifier circuit having an operational amplifier, for example. The amplifier unit 414 amplifies the signal output from the node N1 and outputs the detection signal ABS to the binarization unit 60.

  The light receiving sensor unit 42 (second sensor unit) detects the pattern 20, and the phase of the detection signal ABS (first detection signal) is reversed according to the second light amount generated in the irradiation light through the pattern 20. A detection signal / ABS (second detection signal) which is (reverse phase) is output. The light receiving sensor unit 42 outputs a detection signal / ABS according to the second light amount generated in the light reflected from the pattern 20. That is, the light receiving sensor unit 42 outputs the detection signal / ABS based on, for example, a change in the irradiation light L2 reflected from the reflection unit 20R of the pattern 20. Here, “/” in “/ ABS” is a notation representing an inverted signal.

The light receiving sensor unit 42 includes a light receiving element 421, a power supply unit 422, a resistor 423, and an amplifier unit 424. The light receiving sensor unit 42 includes a plurality of light receiving elements 421 in order to detect a plurality of bits in the M series pattern in parallel, but here, for the sake of explanation, a light receiving detection element group (a plurality of light receiving elements) is provided. One of the elements 411) will be described. The plurality of light receiving elements 421 may be used by switching in time series, for example, and may detect the M series pattern in the pattern 20.
As described above, the light receiving sensor unit 42 (light receiving element 421) is disposed at a position where the irradiation light emitted from the light source unit 3 is incident via the pattern 20.

  The light receiving element 421 (detection element) is, for example, a photodiode, and the current (photocurrent) changes according to the second light quantity (change in the second light quantity) transmitted through the reflecting portion 20R of the pattern 20. For example, the light receiving element 421 has a cathode terminal connected to the power supply unit 422 and an anode terminal connected to the node N2.

The power supply unit 422 is a power supply circuit that supplies a reverse bias to the light receiving element 421.
The resistor 423 is, for example, a resistor element having a predetermined resistance value, and one end is grounded (connected to the ground line) and the other end is connected to the node N2. The resistor 423 converts a change in current by the light receiving element 411 according to a change in the second light amount into a change in voltage.

  The amplifier unit 424 is an amplifier circuit having an operational amplifier, for example. The amplifier unit 424 amplifies the signal output from the node N2 and outputs the detection signal / ABS to the binarization unit 60.

  The binarizing unit 60 generates a binarized signal DABS corresponding to the pattern 20 using the detection signal ABS output from the light receiving sensor unit 41 and the detection signal / ABS output from the light receiving sensor unit 42 as differential signals. The binarization unit 60 outputs the generated binarization signal DABS to the position detection unit 40. In addition, the binarization unit 60 includes a comparator 61, for example.

  The comparator 61 is, for example, a comparator circuit, and generates a binarized signal DABS based on a comparison between the voltage level of the detection signal ABS and the voltage level of the detection signal / ABS. For example, when the voltage level of the detection signal ABS is equal to or higher than the voltage level of the detection signal / ABS, the comparator 61 outputs a signal having a level indicating the logical state “1” as the binarized signal DABS. For example, when the voltage level of the detection signal ABS is less than the voltage level of the detection signal / ABS, the comparator 61 outputs a signal having a level indicating the logic state “0” as the binarized signal DABS.

  The position detector 40 detects position information (eg, angle information) of the rotor 6 based on the binarized signal DABS generated by the binarizer 60. The position detection unit 40 generates a code corresponding to the M series pattern in the pattern 20 based on the binarized signal DABS, and generates absolute position information (eg, angle information) corresponding to the generated code. The position detection unit 40 outputs the generated absolute position information to a host device such as an external controller, for example.

  The substrate (7, 5) described above may be a semiconductor substrate (semiconductor chip) or a printed circuit board. When the substrate (7, 5) is a semiconductor substrate (semiconductor chip), for example, at least the light receiving sensor unit 41 and the binarizing unit 60 are formed as semiconductor circuits on the substrate 7, for example, at least the light receiving sensor unit 41 is The substrate 5 may be formed as a semiconductor circuit. When the components from the light receiving element 411 to the amplifier unit 414 are mounted on the same substrate 7, the possibility of noise being mixed into the detection signal can be reduced as compared with the case where they are mounted on another substrate. In addition, when the light receiving element 421 to the amplifier unit 424 are mounted on the same substrate 5, the possibility that noise is mixed into the detection signal can be reduced as compared with the case where they are mounted on another substrate.

Next, the operation of the encoder 1 in the present embodiment will be described with reference to the drawings.
FIG. 3 is a diagram illustrating the operation of the encoder 1 in the present embodiment.
In FIG. 3, each graph shows a differential signal (detection signal ABS, detection signal / ABS) and a binarized signal DABS corresponding to the position in the rotation direction (detection direction). Here, the waveform W1 indicates the signal waveform of the differential signal (detection signal ABS) output from the light receiving sensor unit 41, and the waveform W2 indicates the signal of the differential signal (detection signal / ABS) output from the light receiving sensor unit 42. The waveform is shown. A waveform W3 represents the binarized signal DABS output from the binarization unit 60.
In FIG. 3, the pattern 20 is formed by a combination of a transmissive portion 20T and a reflective portion 20R.

  The light receiving sensor unit 41 detects the pattern 20 and outputs a detection signal ABS based on the transmission unit 20T of the pattern 20. Here, for example, when the light receiving element 411 is the transmissive part 20T in the pattern 20, the first light quantity increases compared to the reflective part 20R, and the current based on the first light quantity increases. Therefore, the node N1 described above outputs a higher signal level (potential) when it is the transmissive part 20T in the pattern 20 than when it is the reflective part 20R. Further, when the light receiving element 411 is the reflecting portion 20R in the pattern 20, the first light amount is reduced compared to the case where it is the transmitting portion 20T, and the current based on the first light amount is reduced. Therefore, the node N1 described above outputs a lower signal level (potential) when it is the reflection part 20R in the pattern 20 than when it is the transmission part 20T. The amplifier unit 414 amplifies the signal output from the node N1 and outputs a detection signal ABS as indicated by the waveform W1 to the binarization unit 60. Here, the potential Vref indicates an intermediate potential of the change in the detection signal ABS. The amplifier unit 414 outputs, for example, the detection signal ABS that is inverted between the transmission unit 20T and the reflection unit 20R using the potential Vref as a reference potential.

  In addition, the light receiving sensor unit 42 detects the pattern 20 and outputs a detection signal / ABS based on the reflection unit 20 </ b> R of the pattern 20. Here, for example, when the light receiving element 421 is the reflecting portion 20R in the pattern 20, the second light amount is increased as compared with the transmissive portion 20T, and the current based on the second light amount is increased. Therefore, the node N2 described above outputs a higher signal level (potential) when it is the reflection part 20R in the pattern 20 than when it is the transmission part 20T. In addition, when the light receiving element 421 is the transmissive portion 20T in the pattern 20, the second light amount is smaller than that in the reflective portion 20R, and the current based on the second light amount is reduced. Therefore, the node N2 described above outputs a lower signal level (potential) when it is the transmissive part 20T in the pattern 20 than when it is the reflective part 20R. The amplifier unit 424 amplifies the signal output from the node N2 and outputs the detection signal / ABS as shown in the waveform W2 to the binarization unit 60. For example, the amplifier unit 424 outputs the detection signal / ABS that is inverted between the transmission unit 20T and the reflection unit 20R with the potential Vref as a reference potential.

  In this manner, the light receiving sensor unit 41 and the light receiving sensor unit 42 generate two differential signals (detection signal ABS and detection signal / ABS) whose signal levels are inverted from each other. Here, the two differential signals (the detection signal ABS and the detection signal / ABS) whose signal levels are inverted from each other are signals having opposite phases to each other.

  Next, the comparator 61 of the binarization unit 60 binarizes corresponding to the pattern 20 using the detection signal ABS output from the light receiving sensor unit 41 and the detection signal / ABS output from the light receiving sensor unit 42 as differential signals. A signal DABS is generated. For example, when the voltage level of the detection signal ABS is equal to or higher than the voltage level of the detection signal / ABS, the comparator 61 outputs a signal having a level indicating the logic state “1” as the binarized signal DABS. For example, when the voltage level of the detection signal ABS is less than the voltage level of the detection signal / ABS, the comparator 61 outputs a signal having a level indicating the logic state “0” as the binarized signal DABS. In this way, the comparator 61 outputs a binarized signal DABS as shown by the waveform W3.

In FIG. 3, noise NZ indicates an example of a noise signal mixed in the detection signal ABS and the detection signal / ABS due to disturbance or the like. Further, the noise NZ shows an example in the case where the signal fluctuates exceeding a voltage level (reference potential Vref) that is approximately ½ of the signal amplitude of the detection signal ABS and the detection signal / ABS, for example. The reference potential Vref is, for example, a potential used as a reference voltage (fixed threshold voltage) for binarization in a conventional encoder. In the conventional encoder, when noise NZ that crosses the reference potential Vref is mixed in the detection signal ABS, the binarized signal may be inverted by the noise NZ. On the other hand, in the present embodiment, the binarization unit 60 generates the binarized signal DABS based on the differential signals (detection signal ABS and detection signal / ABS). In addition, the binarized signal can be generated without being affected by the noise NZ.
For example, in a conventional encoder, a margin (for example, noise margin) when generating a binarized signal is the voltage range MG1. On the other hand, in the encoder 1 in the present embodiment, the margin (for example, noise margin) when generating the binarized signal DABS is the voltage range MG2 that is wider than the voltage range MG1. That is, the encoder 1 in the present embodiment can widen the margin (for example, noise margin) when generating the binarized signal DABS as compared with the case where a conventional fixed threshold voltage is used.

  Next, the position detector 40 detects position information (eg, angle information) of the rotor 6 based on the binarized signal DABS generated by the binarizer 60.

  As described above, the encoder 1 in this embodiment includes the light source unit 3, the code plate 2, the light receiving sensor unit 41, the light receiving sensor unit 42, the binarizing unit 60, and the position detecting unit 40. ing. The light source unit 3 emits irradiation light, the code plate 2 indicates position information of the rotor 6, and a pattern for causing the irradiation light to generate a first light amount and a second light amount obtained by inverting the first light amount. 20 The light receiving sensor unit 41 outputs a first detection signal (for example, a detection signal ABS) according to the first light amount generated in the irradiation light via the pattern 20. The light receiving sensor unit 42 outputs a second detection signal (for example, detection signal / ABS) according to the second light amount generated in the irradiation light through the pattern 20. The binarizing unit 60 generates a binarized signal DABS corresponding to the position information using the detection signal ABS and the detection signal / ABS as differential signals. The position detection unit 40 detects position information (eg, angle information) based on the binarized signal DABS.

Thereby, in the encoder 1 according to the present embodiment, since the binarization unit 60 generates the binarized signal DABS based on the differential signal, for example, a disturbance such as noise NZ as shown in FIG. When this occurs, the possibility of erroneous detection of the detection signal due to disturbance can be reduced. Therefore, the encoder 1 according to the present embodiment can reduce erroneous detection of position information. That is, the encoder 1 in the present embodiment can realize position detection that is robust against disturbance. Therefore, the encoder 1 in the present embodiment can improve the reliability in detecting the position information of the rotor 6.
In addition, since the encoder 1 in the present embodiment generates the binarized signal DABS based on the differential signal, it is not necessary to generate the reference potential Vref by resistance voltage division as in the related art. Therefore, the encoder 1 according to the present embodiment does not need to adjust the reference potential Vref with a variable resistor or the like, so that the manufacturing process can be simplified.

In the present embodiment, the pattern 20 is formed including a transmission part 20T that transmits the irradiation light and a reflection part 20R that reflects the irradiation light. The light receiving sensor unit 41 outputs a detection signal ABS according to the first light amount generated in the light transmitted through the pattern 20, and the light receiving sensor unit 42 corresponds to the second light amount generated in the light reflected from the pattern 20. The detection signal / ABS is output.
Accordingly, the encoder 1 according to the present embodiment generates a differential signal (detection signal ABS and detection signal / ABS) using one pattern 20 based on the transmission unit 20T and the reflection unit 20R. be able to.

In the present embodiment, the pattern 20 is formed so as to indicate position information by a combination of the transmission part 20T and the reflection part 20R.
Thereby, the encoder 1 in the present embodiment can generate a differential signal (detection signal ABS and detection signal / ABS) by one track. Therefore, the encoder 1 in the present embodiment can reduce the size of the code plate 2.

In the present embodiment, the light source unit 3 is configured such that the light source unit 3 has a shorter direction (e.g., diameter) of the pattern 20 than the longitudinal direction of the pattern 20 that is the detection direction of position information (e.g., circumferential direction). It is arranged at a position distant in the direction). Each of the light receiving sensor unit 41 and the light receiving sensor unit 42 is disposed at a position where irradiation light emitted from the light source unit 3 is incident via the pattern 20.
Thereby, since the light source unit 3 irradiates the pattern 20 with the irradiation light from the shorter direction of the pattern 20 different from the detection direction of the position information, the light receiving sensor unit 41 and the light receiving sensor unit 42 have The amount of irradiation light can be received more efficiently than when irradiating from the detection direction. For this reason, the light receiving sensor unit 41 and the light receiving sensor unit 42 can increase the signal level (signal amplitude) of the detection signal ABS and the detection signal / ABS, so the encoder 1 in this embodiment generates a binarized signal. The margin when doing so can be widened.

In the present embodiment, the light source unit 3 and the light receiving sensor unit 42 (light receiving element 421) are mounted on the same substrate 7.
Thereby, the encoder 1 in this embodiment can reduce the size of the detection system (for example, a detection header including the light source unit 3 and the light receiving sensor units (41, 42)). In addition, since both the arrangement of the light source unit 3 and the arrangement of the light receiving element 421 can be adjusted at the same time, the encoder 1b in the present embodiment simplifies the manufacturing process of adjusting the arrangement of the light source unit 3 and the light receiving element 421. Can be

In addition, the code | symbol plate 2 in this embodiment shows the positional information on the rotor 6 (driven body), and the 1st light quantity and the 2nd light quantity which reversed the 1st light quantity are inject | emitted from the light source part 3. FIG. The pattern 20 to be generated in the irradiation light is provided.
Thus, the position information can be detected by the encoder 1 based on the differential signal (detection signal ABS, detection signal / ABS), so that erroneous detection of the position information can be reduced. Therefore, the code plate 2 in the present embodiment can improve the reliability similarly to the encoder 1. Moreover, the code | symbol plate 2 in this embodiment can acquire the effect similar to the encoder 1 mentioned above.

Next, a second embodiment will be described with reference to the drawings.
[Second Embodiment]
In this embodiment, as in the first embodiment, a rotary encoder will be described as an example.
FIG. 4 is a schematic configuration diagram showing an example of the configuration of the encoder 1a according to the second embodiment.
In FIG. 4, the encoder 1 a includes a substrate 7 a and a rotor 6 coupled to a code plate 2 a (disk). The encoder 1a detects position information (for example, angular position information) of the rotor 6 (driven body).

Here, FIG. 4A shows the configuration of the encoder 1a as viewed from the rotation axis direction (Z-axis direction) of the rotor 6, and FIGS. 4B and 4C are views as viewed from the Y-axis direction. The arrangement of the code plate 2a and the substrate 7a is shown. In FIG. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.
In the present embodiment, an example of generating a differential signal (detection signal ABS and detection signal / ABS) using the reflection pattern 20a (two-track reflection patterns (21, 22)) will be described.

  As shown in FIG. 4, the code plate 2 a is a disk coupled to the rotor 6, and includes, for example, a pattern 20 a formed by two tracks of reflection patterns (21, 22). The substrate 7 a includes at least the light source unit 3, the light receiving element 411, and the light receiving element 421.

  The pattern 20 a indicates position information of the rotor 6, and generates a first light amount and a second light amount obtained by inverting the first light amount in the irradiation light emitted from the light source unit 3. The pattern 20a includes a reflection pattern 21 that generates a first light amount and a reflection pattern 22 that generates a second light amount.

  The reflective pattern 21 (first pattern) is formed by a combination of a reflective portion 21R and a non-reflective portion 21NR, and is an absolute pattern that indicates an absolute position by an M (M) series, for example. Here, the non-reflecting part 21NR is a part having a lower reflectance than the reflecting part 21R.

  The reflective pattern 22 (second pattern) is formed by a combination of the reflective portion 22R and the non-reflective portion 22NR, and is formed by an inverted pattern of the reflective pattern 21. That is, in the reflective pattern 22, the position corresponding to the reflective part 21R of the reflective pattern 21 is formed by the non-reflective part 22NR, and the position corresponding to the non-reflective part 21NR of the reflective pattern 21 is formed by the reflective part 22R. . Here, the non-reflective portion 22NR is a portion having a lower reflectance than the reflective portion 22R.

  In addition, the pattern 20a may form the reflective surface (reflective part 21R, reflective part 22R) which shows M series in the code | cord | chord plate 2a by vapor deposition, such as aluminum, for example, and the mirror surface process by cutting (process polished to a mirror surface) It may be formed by performing.

The substrate 7a is disposed so that the light emitting surface of the light source unit 3 and the light receiving surface of the light receiving elements (411, 421) of the substrate 7a face the reflecting portions (21R, 22R) of the pattern 20a.
4B, the light receiving element 411 is disposed at a position where the irradiation light emitted by the light source unit 3 receives the irradiation light L1a reflected by the reflection portion 21R of the reflection pattern 21. As shown in FIG. For example, the light receiving element 411 is disposed at a position where the irradiation light L1a emitted from the light source unit 3 is incident via the reflection pattern 21 (reflection unit 21R). Here, the light quantity including the irradiation light L1a received by the light receiving element 411 corresponds to the first light quantity.

Further, as shown in FIG. 4C, the light receiving element 421 is disposed at a position where the irradiation light emitted by the light source unit 3 receives the irradiation light L <b> 2 a reflected by the reflection part 22 </ b> R of the reflection pattern 22. For example, the light receiving element 421 is disposed at a position where the irradiation light L2a emitted from the light source unit 3 is incident through the reflection pattern 22 (reflection unit 22R). Here, the light amount including the irradiation light L2a received by the light receiving element 421 corresponds to the second light amount.
Note that, as shown in FIGS. 4B and 4C, the reflective pattern 21 and the reflective pattern 22 are formed in patterns reversed from each other.

FIG. 4B shows an example in which the rotational position of the rotor 6 is at the position of the reflecting portion 21R of the reflecting pattern 21 and the position of the non-reflecting portion 22NR of the reflecting pattern 22. In this case, the first light amount described above increases and the second light amount decreases.
4C shows an example in which the rotational position of the rotor 6 is at the position of the non-reflecting part 21NR of the reflective pattern 21 and the position of the reflective part 22R of the reflective pattern 22. FIG. In this case, the first light amount described above is reduced and the second light amount is increased. As described above, the first light amount and the second light amount are in a mutually inverted relationship. Note that the inversion of the light amount includes, for example, inversion of change in the light amount, inversion of the light intensity distribution, and the like. That is, the change in the first light amount and the change in the second light amount are in a mutually inverted relationship.

  In addition, since the block diagram which shows the structure of the encoder 1a in this embodiment is the same as that of FIG. 2, description is abbreviate | omitted here.

Next, the operation of the encoder 1a in the present embodiment will be described with reference to the drawings.
FIG. 5 is a diagram showing the operation of the encoder 1a in the present embodiment.
In FIG. 5, each graph shows a differential signal (detection signal ABS, detection signal / ABS) and a binarized signal DABS corresponding to the position in the rotation direction (detection direction). Here, the waveform W4 indicates the signal waveform of the differential signal (detection signal ABS) output from the light receiving sensor unit 41, and the waveform W5 indicates the signal of the differential signal (detection signal / ABS) output from the light receiving sensor unit 42. The waveform is shown. A waveform W6 indicates the binarized signal DABS output from the binarizing unit 60.
Further, as shown in FIG. 5, the reflective pattern 21 is formed by a combination of a reflective part 21R and a non-reflective part 21NR, and the reflective pattern 22 is formed by a combination of a reflective part 22R and a non-reflective part 22NR. ing.

  The light receiving sensor unit 41 outputs a detection signal ABS according to the first light amount based on the reflection pattern 21. For example, the light receiving sensor unit 41 detects the reflection pattern 21 and outputs a detection signal ABS based on the reflection unit 21 </ b> R of the reflection pattern 21. Here, for example, when the light receiving element 411 is the reflecting portion 21R in the reflective pattern 21, the first light amount increases compared to the non-reflecting portion 21NR, and the current based on the first light amount increases. Therefore, the node N1 described above outputs a higher signal level (potential) when it is the reflection part 21R in the reflection pattern 21 than when it is the non-reflection part 21NR. Further, when the light receiving element 411 is the non-reflecting part 21NR in the reflective pattern 21, the first light quantity is reduced compared to the case where it is the reflecting part 21R, and the current based on the first light quantity is reduced. Therefore, the node N1 described above outputs a lower signal level (potential) when it is the non-reflecting part 21NR in the reflecting pattern 21 than when it is the reflecting part 21R. The amplifier unit 414 amplifies the signal output from the node N1 and outputs a detection signal ABS as indicated by the waveform W4 to the binarization unit 60. Here, the potential Vref indicates an intermediate potential of the change in the detection signal ABS. For example, the amplifier unit 414 outputs the detection signal ABS that is inverted between the reflecting unit 21R and the non-reflecting unit 21NR with the potential Vref as a reference potential.

  In addition, the light receiving sensor unit 42 outputs a detection signal / ABS according to the second light quantity based on the reflection pattern 22. For example, the light receiving sensor unit 42 detects the reflection pattern 22 and outputs a detection signal / ABS based on the reflection unit 22 </ b> R of the reflection pattern 22. Here, for example, when the light receiving element 421 is the reflection part 22R in the reflection pattern 22, the second light quantity increases compared to the non-reflection part 22NR, and the current based on the second light quantity increases. Therefore, the node N2 described above outputs a higher signal level (potential) when it is the reflection part 22R in the reflection pattern 22 than when it is the non-reflection part 22NR. Further, when the light receiving element 421 is the non-reflecting portion 22NR in the reflective pattern 22, the second light amount is reduced compared to the case where it is the reflecting portion 22R, and the current based on the second light amount is reduced. Therefore, the node N2 described above outputs a lower signal level (potential) when the reflection pattern 22 is the non-reflection part 22NR than when it is the reflection part 22R. The amplifier unit 424 amplifies the signal output from the node N2 and outputs the detection signal / ABS as shown in the waveform W5 to the binarization unit 60. For example, the amplifier unit 424 outputs the detection signal / ABS that is inverted between the reflection unit 22R and the non-reflection unit 22NR with the potential Vref as a reference potential.

In this manner, the light receiving sensor unit 41 and the light receiving sensor unit 42 generate two differential signals (detection signal ABS and detection signal / ABS) whose signal levels are inverted from each other.
The subsequent operation of the comparator 61 of the binarizing unit 60 is the same as that of the first embodiment, and the comparator 61 outputs a binarized signal DABS as shown by the waveform W6.

  As described above, the encoder 1a in the present embodiment includes the light source unit 3, the code plate 2a, the light receiving sensor unit 41, the light receiving sensor unit 42, the binarizing unit 60, and the position detecting unit 40. ing. The light source unit 3 emits irradiation light, the code plate 2a indicates position information of the rotor 6, and a pattern for causing the irradiation light to generate a first light amount and a second light amount obtained by inverting the first light amount. 20a. The pattern 20a includes a reflection pattern 21 that generates a first light amount and a reflection pattern 22 that is formed by an inverted pattern of the reflection pattern 21 and generates a second light amount. The light receiving sensor unit 41 outputs a first detection signal (for example, a detection signal ABS) according to the first light amount based on the reflection pattern 21. The light receiving sensor unit 42 outputs a second detection signal (eg, detection signal / ABS) according to the second light amount based on the reflection pattern 22. The binarizing unit 60 generates a binarized signal DABS corresponding to the position information using the detection signal ABS and the detection signal / ABS as differential signals. The position detection unit 40 detects position information (eg, angle information) based on the binarized signal DABS.

  As a result, the encoder 1a according to the present embodiment has a possibility of erroneously detecting a detection signal due to a disturbance, for example, when a disturbance such as noise NZ as shown in FIG. 3 occurs as in the first embodiment. Can be reduced. Therefore, the encoder 1a according to the present embodiment can reduce erroneous detection of position information. Therefore, the encoder 1a in the present embodiment can improve the reliability in detecting the position information of the rotor 6, as in the first embodiment.

  Further, the encoder 1a in the present embodiment forms the pattern 20a only with the reflection patterns (21, 22), and it is not necessary to form the transmission part 20T as in the first embodiment. In comparison, the manufacturing process of the code plate 2a can be simplified. Further, since the light source unit 3 and the light receiving elements (411, 422) can be mounted on the substrate 7a, and the substrate 5 in the first embodiment is unnecessary, the encoder 1a in the present embodiment is the first implementation. Compared to the form, the configuration can be simplified. Moreover, the encoder 1a in this embodiment can simplify the manufacturing process which adjusts arrangement | positioning of the light receiving element 411 by mounting the light receiving element 411 on the board | substrate 7a.

Next, a third embodiment will be described with reference to the drawings.
[Third Embodiment]
In this embodiment, as in the first embodiment, a rotary encoder will be described as an example.
FIG. 6 is a schematic configuration diagram showing an example of the configuration of the encoder 1b according to the third embodiment.
In FIG. 6, the encoder 1b includes a substrate (7b, 5a) and a rotor 6 coupled to a code plate 2b (disk). The encoder 1b detects position information (for example, angular position information) of the rotor 6 (driven body).

Here, FIG. 6A shows the configuration of the encoder 1b viewed from the rotation axis direction (Z-axis direction) of the rotor 6, and FIGS. 6B and 6C show the configuration viewed from the Y-axis direction. The arrangement of the code plates 2b and (7b, 5a) is shown. In FIG. 6, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.
In the present embodiment, an example will be described in which differential signals (detection signal ABS and detection signal / ABS) are generated using a reflective pattern 20b (two-track transmission patterns (21a, 22a)).

  As shown in FIG. 6, the code plate 2b is a disk coupled to the rotor 6 and includes, for example, a pattern 20b formed by two tracks of transmission patterns (21a, 22a). The substrate 7 b includes at least the light source unit 3, and the substrate 5 a includes at least a light receiving element 411 and a light receiving element 421.

  The pattern 20 b indicates position information of the rotor 6, and generates a first light amount and a second light amount obtained by inverting the first light amount in the irradiation light emitted from the light source unit 3. The pattern 20b includes a transmission pattern 21a that generates a first light amount and a transmission pattern 22a that generates a second light amount.

  The transmissive pattern 21a (first pattern) is formed by a combination of the transmissive portion 21T and the non-transmissive portion 21NT, and is an absolute pattern that indicates an absolute position by an M (M) series, for example. Here, the non-transmissive portion 21NT is a portion having a lower light transmittance than the transmissive portion 21T.

The transmissive pattern 22a (second pattern) is formed by a combination of the transmissive portion 22T and the non-transmissive portion 22NT, and is formed by an inverted pattern of the transmissive pattern 21a. That is, in the transmissive pattern 22a, a position corresponding to the transmissive portion 21T of the transmissive pattern 21a is formed by the non-transmissive portion 22NT, and a position corresponding to the non-transmissive portion 21NT of the transmissive pattern 21a is formed by the transmissive portion 22T. . Here, the non-transmissive portion 22NT is a portion having a lower light transmittance than the transmissive portion 22T.
The pattern 20a may be formed, for example, by forming a transmission part 20T showing an M series by etching on the code plate 2b.

The substrate 7b and the substrate 5a are arranged with the code plate 2b sandwiched so that the light emitting surface of the light source unit 3 of the substrate 7b and the light receiving surfaces of the light receiving elements 411 and 421 of the substrate 5a face each other.
Further, as shown in FIG. 6B, the light receiving element 411 is disposed at a position where the irradiation light emitted by the light source unit 3 receives the irradiation light L1b transmitted through the transmission part 21T of the transmission pattern 21a. For example, the light receiving element 411 is disposed at a position where the irradiation light L1b emitted from the light source unit 3 is incident through the transmission pattern 21a (transmission unit 21T). Here, the light quantity including the irradiation light L1b received by the light receiving element 411 corresponds to the first light quantity.

Further, as shown in FIG. 6C, the light receiving element 421 is disposed at a position where the irradiation light emitted by the light source unit 3 receives the irradiation light L2b transmitted through the transmission part 22T of the transmission pattern 22a. For example, the light receiving element 421 is disposed at a position where the irradiation light L2b emitted from the light source unit 3 is incident through the transmission pattern 22a (the transmission unit 22T). Here, the light amount including the irradiation light L2b received by the light receiving element 421 corresponds to the second light amount.
Note that, as shown in FIGS. 6B and 6C, the transmissive pattern 21a and the transmissive pattern 22a are formed in patterns reversed from each other.

FIG. 6B shows an example where the rotational position of the rotor 6 is at the position of the transmissive part 21T of the transmissive pattern 21a and the position of the non-transmissive part 22NT of the transmissive pattern 22a. In this case, the first light amount described above increases and the second light amount decreases.
FIG. 6C shows an example in which the rotation position of the rotor 6 is at the position of the non-transmission part 21NT of the transmission pattern 21a and the position of the transmission part 22T of the transmission pattern 22a. In this case, the first light amount described above is reduced and the second light amount is increased. As described above, the first light amount and the second light amount are in a mutually inverted relationship. Note that the inversion of the light amount includes, for example, inversion of change in the light amount, inversion of the light intensity distribution, and the like. That is, the change in the first light amount and the change in the second light amount are in a mutually inverted relationship.

  In addition, since the block diagram which shows the structure of the encoder 1b in this embodiment is the same as that of FIG. 2, description is abbreviate | omitted here.

Next, the operation of the encoder 1b in the present embodiment will be described with reference to the drawings.
FIG. 7 is a diagram illustrating the operation of the encoder 1b in the present embodiment.
In FIG. 7, each graph shows a differential signal (detection signal ABS, detection signal / ABS) and a binarized signal DABS corresponding to the position in the rotation direction (detection direction). Here, the waveform W7 indicates the signal waveform of the differential signal (detection signal ABS) output from the light receiving sensor unit 41, and the waveform W8 indicates the signal of the differential signal (detection signal / ABS) output from the light receiving sensor unit 42. The waveform is shown. A waveform W9 represents the binarized signal DABS output from the binarization unit 60.
As shown in FIG. 7, the transmissive pattern 21a is formed by a combination of a transmissive portion 21T and a non-transmissive portion 21NT, and the transmissive pattern 22a is formed by a combination of a transmissive portion 22T and a non-transmissive portion 22NT. ing.

  The light receiving sensor unit 41 outputs a detection signal ABS according to the first light quantity based on the transmission pattern 21a. For example, the light receiving sensor unit 41 detects the transmission pattern 21a and outputs a detection signal ABS based on the transmission unit 21T of the transmission pattern 21a. Here, for example, when the light receiving element 411 is the transmissive part 21T in the transmissive pattern 21a, the first light quantity increases compared to the non-transmissive part 21NT, and the current based on the first light quantity increases. Therefore, the node N1 described above outputs a higher signal level (potential) when it is the transmissive portion 21T in the transmissive pattern 21a than when it is the non-transmissive portion 21NT. Further, when the light receiving element 411 is the non-transmissive part 21NT in the transmissive pattern 21a, the first light quantity is reduced compared to the case where it is the transmissive part 21T, and the current based on the first light quantity is reduced. Therefore, the node N1 described above outputs a lower signal level (potential) when it is the non-transmissive part 21NT in the transmissive pattern 21a than when it is the transmissive part 21T. The amplifier unit 414 amplifies the signal output from the node N1 and outputs a detection signal ABS as indicated by the waveform W7 to the binarization unit 60. Here, the potential Vref indicates an intermediate potential of the change in the detection signal ABS. For example, the amplifier unit 414 outputs the detection signal ABS that is inverted between the transmission unit 21T and the non-transmission unit 21NT using the potential Vref as a reference potential.

  In addition, the light receiving sensor unit 42 outputs a detection signal / ABS according to the second light quantity based on the transmission pattern 22a. For example, the light receiving sensor unit 42 detects the transmission pattern 22a and outputs a detection signal / ABS based on the transmission unit 22T of the transmission pattern 22a. Here, for example, when the light receiving element 421 is the transmissive part 22T in the transmissive pattern 22a, the second light quantity increases compared to the non-transmissive part 22NT, and the current based on the second light quantity increases. Therefore, the node N2 described above outputs a higher signal level (potential) when it is the transmissive part 22T in the transmissive pattern 22a than when it is the non-transmissive part 22NT. Further, when the light receiving element 421 is the non-transmissive part 22NT in the transmissive pattern 22a, the second light quantity is reduced compared to the case of the transmissive part 22T, and the current based on the second light quantity is reduced. Therefore, the node N2 described above outputs a lower signal level (potential) when it is the non-transmissive portion 22NT in the transmissive pattern 22a than when it is the transmissive portion 22T. The amplifier unit 424 amplifies the signal output from the node N2, and outputs a detection signal / ABS as indicated by the waveform W8 to the binarization unit 60. For example, the amplifier unit 424 outputs the detection signal / ABS that is inverted between the transmission unit 22T and the non-transmission unit 22NT using the potential Vref as a reference potential.

In this manner, the light receiving sensor unit 41 and the light receiving sensor unit 42 generate two differential signals (detection signal ABS and detection signal / ABS) whose signal levels are inverted from each other.
The subsequent operation of the comparator 61 of the binarization unit 60 is the same as that of the first embodiment, and the comparator 61 outputs a binarized signal DABS as shown by the waveform W9.

  As described above, the encoder 1b in the present embodiment includes the light source unit 3, the code plate 2b, the light receiving sensor unit 41, the light receiving sensor unit 42, the binarizing unit 60, and the position detecting unit 40. ing. The light source unit 3 emits irradiation light, the code plate 2b indicates position information of the rotor 6, and a pattern that causes the irradiation light to generate a first light amount and a second light amount obtained by inverting the first light amount. 20b. The pattern 20b includes a transmissive pattern 21a that generates a first light amount and a transmissive pattern 22a that is formed by an inverted pattern of the transmissive pattern 21a and generates a second light amount. The light receiving sensor unit 41 outputs a first detection signal (for example, a detection signal ABS) in accordance with the first light amount based on the transmission pattern 21a. The light receiving sensor unit 42 outputs a second detection signal (for example, detection signal / ABS) according to the second light amount based on the transmission pattern 22a. The binarizing unit 60 generates a binarized signal DABS corresponding to the position information using the detection signal ABS and the detection signal / ABS as differential signals. The position detection unit 40 detects position information (eg, angle information) based on the binarized signal DABS.

  As a result, the encoder 1b according to the present embodiment has the possibility of erroneously detecting the detection signal due to the disturbance, for example, when a disturbance such as the noise NZ shown in FIG. 3 occurs as in the first embodiment. Can be reduced. Therefore, the encoder 1b according to the present embodiment can reduce erroneous detection of position information. Therefore, the encoder 1b in the present embodiment can improve the reliability in detecting the position information of the rotor 6 as in the first embodiment.

  Further, the encoder 1b in the present embodiment forms the pattern 20b only with the transmission patterns (21a, 22a), and it is not necessary to form the reflecting portion 20R as in the first embodiment. In comparison, the manufacturing process of the code plate 2b can be simplified. Further, the encoder 1b according to the present embodiment can adjust both the arrangement of the light receiving elements 411 and the light receiving elements 421 at the same time by mounting the light receiving elements 411 and 421 on the substrate 5a. Therefore, the encoder 1b in the present embodiment can simplify the manufacturing process for adjusting the arrangement of the light receiving elements (411, 421).

Next, a fourth embodiment will be described with reference to the drawings.
[Fourth Embodiment]
In this embodiment, as in the first embodiment, a rotary encoder will be described as an example.
FIG. 8 is a schematic configuration diagram illustrating an example of a configuration of an encoder 1c according to the fourth embodiment.
In FIG. 8, an encoder 1c includes a substrate (7c, 5b) and a rotor 6 coupled to a code plate 2c (disk). The encoder 1c detects position information (for example, angular position information) of the rotor 6 (driven body).

Here, FIG. 8A shows the configuration of the encoder 1c as viewed from the rotation axis direction (Z-axis direction) of the rotor 6, and FIGS. 8B and 8C are views as viewed from the Y-axis direction. The arrangement of the code plate 2c and the substrates (7c, 5b) is shown. In FIG. 8, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.
In the present embodiment, an example in which a differential signal (detection signal ABS and detection signal / ABS) is generated using the pattern 20c (two tracks of the transmission pattern 21b and the reflection pattern 22b) will be described.

  As shown in FIG. 8, the code plate 2c is a disk coupled to the rotor 6, and includes, for example, a pattern 20c formed by two tracks of a transmission pattern 21b and a reflection pattern 22b. The substrate 7 c includes at least the light source unit 3 and the light receiving element 421, and the substrate 5 b includes at least the light receiving element 411.

  The pattern 20 c indicates position information of the rotor 6, and generates a first light amount and a second light amount obtained by inverting the first light amount in the irradiation light emitted from the light source unit 3. For example, the pattern 20c is formed to include a transmission part 21T that transmits the irradiation light and a reflection part 22R that reflects the irradiation light. The pattern 20c generates a first light amount in the light transmitted through the pattern 20c, and the pattern 20c. A second light amount is generated in the reflected light. The pattern 20c includes a transmission pattern 21b that generates a first light amount and a reflection pattern 22b that generates a second light amount.

  The transmissive pattern 21b (first pattern) is formed by a combination of the transmissive portion 21T and the non-transmissive portion 21NT, and is, for example, an absolute pattern that indicates an absolute position by an M (M) series. Here, the non-transmissive portion 21NT is a portion having a lower light transmittance than the transmissive portion 21T.

The reflective pattern 22b (second pattern) is formed by a combination of the reflective portion 22R and the non-reflective portion 22NR. For example, in the reflection pattern 22b, a position corresponding to the transmission part 21T of the transmission pattern 21b is formed by the non-reflection part 22NR, and a position corresponding to the non-transmission part 21NT of the transmission pattern 21b is formed by the reflection part 22R. . Here, the non-reflective portion 22NR is a portion having a lower light reflectance than the reflective portion 22R. In the present embodiment, the non-transmissive part 21NT and the non-reflective part 22NR are formed with the same configuration.
The pattern 20c is formed, for example, by forming a transmissive portion 21T indicating the M series by etching on the code plate 2c. Further, for example, the reflection pattern 22b is formed by forming the reflection portion 22R showing an M-series reversal pattern by mirror surface processing (processing to polish the mirror surface) by vapor deposition or cutting of aluminum or the like.

The substrate 7c and the substrate 5b are disposed with the code plate 2c interposed therebetween so that the light emitting surface and the light receiving element 421 of the light source unit 3 of the substrate 7c face the light receiving surface of the light receiving element 411 of the substrate 5b.
Further, as shown in FIG. 8B, the light receiving element 411 is disposed at a position where the irradiation light emitted from the light source unit 3 receives the irradiation light L1c transmitted through the transmission part 21T of the transmission pattern 21b. For example, the light receiving element 411 is disposed at a position where the irradiation light L1c emitted from the light source unit 3 is incident through the transmission pattern 21b (the transmission unit 21T). Here, the light quantity including the irradiation light L1c received by the light receiving element 411 corresponds to the first light quantity.

  Further, as shown in FIG. 8C, the light receiving element 421 is disposed at a position where the irradiation light emitted from the light source unit 3 receives the irradiation light L2c transmitted through the reflection portion 22R of the reflection pattern 22b. For example, the light receiving element 421 is disposed at a position where the irradiation light L2c emitted from the light source unit 3 is incident via the reflection pattern 22b (reflection unit 22R). Here, the light amount including the irradiation light L2c received by the light receiving element 421 corresponds to the second light amount.

FIG. 8B shows an example where the rotational position of the rotor 6 is at the position of the transmissive part 21T of the transmissive pattern 21b and the position of the non-transmissive part 22NT (non-reflective part 22NR) of the reflective pattern 22b. ing. In this case, the first light amount described above increases and the second light amount decreases.
FIG. 8C shows an example in which the rotational position of the rotor 6 is at the position of the non-transmissive part 21NT of the transmissive pattern 21b and the position of the reflective part 22R of the reflective pattern 22b. In this case, the first light amount described above is reduced and the second light amount is increased. As described above, the first light amount and the second light amount are in a mutually inverted relationship. Note that the inversion of the light amount includes, for example, inversion of change in the light amount, inversion of the light intensity distribution, and the like. That is, the change in the first light amount and the change in the second light amount are in a mutually inverted relationship.

  In addition, since the block diagram which shows the structure of the encoder 1c in this embodiment is the same as that of FIG. 2, description is abbreviate | omitted here.

Next, the operation of the encoder 1c in the present embodiment will be described with reference to the drawings.
FIG. 9 is a diagram illustrating the operation of the encoder 1c in the present embodiment.
In FIG. 9, each graph shows a differential signal (detection signal ABS, detection signal / ABS) and a binarized signal DABS corresponding to the position in the rotation direction (detection direction). Here, the waveform W10 shows the signal waveform of the differential signal (detection signal ABS) output from the light receiving sensor unit 41, and the waveform W11 is the signal of the differential signal (detection signal / ABS) output from the light receiving sensor unit 42. The waveform is shown. A waveform W12 represents the binarized signal DABS output from the binarization unit 60.
As shown in FIG. 9, the transmissive pattern 21b is formed by a combination of a transmissive part 21T and a non-transmissive part 21NT, and the reflective pattern 22b is composed of a reflective part 22R and a non-reflective part 22NR (non-transmissive part 22NT). It is formed by the combination.

  The light receiving sensor unit 41 outputs a detection signal ABS according to the first light quantity based on the transmission pattern 21b. For example, the light receiving sensor unit 41 detects the transmission pattern 21b and outputs a detection signal ABS based on the transmission unit 21T of the transmission pattern 21b. Here, the light receiving sensor unit 41 operates in the same manner as in the third embodiment, and outputs a detection signal ABS as shown by the waveform W10 to the binarization unit 60. Here, the potential Vref indicates an intermediate potential of the change in the detection signal ABS. For example, the amplifier unit 414 outputs the detection signal ABS that is inverted between the transmission unit 21T and the non-transmission unit 21NT using the potential Vref as a reference potential.

  Further, the light receiving sensor unit 42 outputs a detection signal / ABS according to the second light quantity based on the reflection pattern 22b. For example, the light receiving sensor unit 42 detects the reflection pattern 22b and outputs a detection signal / ABS based on the reflection unit 22R of the reflection pattern 22b. Here, the light receiving sensor unit 42 operates in the same manner as in the second embodiment, and outputs a detection signal / ABS as shown by the waveform W11 to the binarization unit 60. For example, the amplifier unit 424 outputs the detection signal / ABS that is inverted between the reflection unit 22R and the non-reflection unit 22NR with the potential Vref as a reference potential.

In this manner, the light receiving sensor unit 41 and the light receiving sensor unit 42 generate two differential signals (detection signal ABS and detection signal / ABS) whose signal levels are inverted from each other.
The subsequent operation of the comparator 61 of the binarization unit 60 is the same as that of the first embodiment, and the comparator 61 outputs a binarized signal DABS as shown by the waveform W12.

  As described above, the encoder 1c in the present embodiment includes the light source unit 3, the code plate 2b, the light receiving sensor unit 41, the light receiving sensor unit 42, the binarizing unit 60, and the position detecting unit 40. ing. The light source unit 3 emits irradiation light, and the code plate 2c indicates position information of the rotor 6, and generates a first light amount and a second light amount obtained by inverting the first light amount in the irradiation light. 20c. The pattern 20c includes a transmission pattern 21b that generates a first light amount and a reflection pattern 22b that generates a second light amount. The transmission pattern 21b of the pattern 20c is formed by a combination of a transmission part 21T and a non-transmission part 21NT having a lower transmittance than the transmission part 21T. The reflective pattern 22b of the pattern 20c is formed by a combination of a reflective portion 22R and a non-reflective portion 22NR having a lower reflectance than the reflective portion 22R. The light receiving sensor unit 41 outputs a first detection signal (for example, a detection signal ABS) in accordance with the first light quantity based on the transmission pattern 21b. The light receiving sensor unit 42 outputs a second detection signal (eg, detection signal / ABS) according to the second light amount based on the reflection pattern 22b. The binarizing unit 60 generates a binarized signal DABS corresponding to the position information using the detection signal ABS and the detection signal / ABS as differential signals. The position detection unit 40 detects position information (eg, angle information) based on the binarized signal DABS.

  As a result, the encoder 1c according to the present embodiment has the possibility of erroneously detecting the detection signal due to the disturbance when a disturbance such as noise NZ as shown in FIG. 3 occurs, for example, as in the first embodiment. Can be reduced. Therefore, the encoder 1c according to the present embodiment can reduce erroneous detection of position information. Therefore, the encoder 1c in the present embodiment can improve the reliability in detecting the position information of the rotor 6 as in the first embodiment.

Next, a fifth embodiment will be described with reference to the drawings.
[Fifth Embodiment]
In this embodiment, as in the first embodiment, a rotary encoder will be described as an example.
FIG. 10 is a schematic configuration diagram illustrating an example of a configuration of an encoder 1d according to the fifth embodiment.
In FIG. 10, an encoder 1d includes a substrate (7d, 5c) and a rotor 6 coupled to a code plate 2d (disk). The encoder 1d detects position information (for example, angular position information) of the rotor 6 (driven body).

  Here, FIG. 10A shows the configuration of the encoder 1d as seen from the rotational axis direction (Z-axis direction) of the rotor 6, and FIGS. 10B and 10C are views from the Y-axis direction. The arrangement of the code plate 2d and the substrates (7d, 5c) is shown. In FIG. 10, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

In the present embodiment, an example in which the pattern 20d indicates absolute position information by multitrack using a Gray code instead of the M series will be described.
As shown in FIG. 10, the code plate 2d is a disk coupled to the rotor 6 and includes, for example, a pattern 20d in which a gray code (eg, X-bit gray code) is formed by a plurality of tracks. . Each of the plurality of tracks is a transmission / reflection pattern having a transmission portion 20T and a reflection portion 20R in one track, similar to the pattern 20 in the first embodiment. Here, for example, the code plate 2d has a plurality of (eg, X) transmission / reflection patterns 20d-1 to 20d-X.

  The substrate 7d includes at least the light source unit 3 and the light receiving elements 421 (421-1 to 421-X), and the substrate 5c includes at least the light receiving elements 411 (421-1 to 421-X). In FIG. 10B and FIG. 10C, for the sake of explanation, the light receiving elements 411-1 to 411-3 and the light receiving elements 421-1 to 421-3 are illustrated, and the other light receiving elements are omitted. To explain. In addition, the light receiving elements 411-1 to 411 -X have the same configuration as the light receiving element 411 in the first embodiment, and when any light receiving element among the light receiving elements 411-1 to 411 -X is shown. The light receiving element 411 will be described below. In addition, the light receiving elements 421-1 to 421-X have the same configuration as the light receiving element 421 in the first embodiment, and when any light receiving element among the light receiving elements 421-1 to 421-X is shown. The light receiving element 421 will be described below.

  As shown in FIG. 10 (b), the light receiving elements 411-1 to 411-3 pass through the transmission part 20T in which the irradiation light emitted by the light source part 3 is a pattern 20d (transmission reflection patterns 20d-1 to 20d-3). It arrange | positions in the position which receives the transmitted irradiation light. In the example illustrated in FIG. 10B, the transmission / reflection pattern 20d-1 to 20d-3 are all transmissive portions 20T. In this case, similarly to the first embodiment, the first light amount described above increases and the second light amount decreases.

  As shown in FIG. 10 (c), the light receiving elements 421-1 to 421-3 pass through the reflecting portion 20R of the pattern 20d (transmission reflection patterns 20d-1 to 20d-3) emitted from the light source unit 3. It arrange | positions in the position which receives the reflected irradiated light. In the example shown in FIG. 10C, the transmission / reflection patterns 20d-1 to 20d-3 are all reflective portions 20R. In this case, similarly to the first embodiment, the second light amount described above increases and the first light amount decreases.

FIG. 11 is a block diagram illustrating an example of the encoder 1d according to the present embodiment.
11, the encoder 1d includes a light source unit 3, a position detection unit 40a, light receiving sensor units 41-1 to 41-X, light receiving sensor units 42-1 to 42-X, and a binarization unit 60-X. Yes.

  Each of the light receiving sensor units 41-1 to 41-X (first sensor unit) has the same configuration as the light receiving sensor unit 41 in the first embodiment, detects the pattern 20d, and emits light through the pattern 20d. The detection signals ABS1 to ABSX (first detection signal) are output in accordance with the first light quantity generated in the step. The light receiving sensor units 41-1 to 41-X in the present embodiment are each provided with one light receiving element 411 (411) instead of including a plurality of light receiving elements 411 as in the light receiving sensor unit 41 in the first embodiment. -1 to 411-X). Here, for example, the light receiving sensor unit 41-1 detects the detection signal ABS1 according to the first light amount based on the transmission / reflection pattern 20d-1, and the light reception sensor unit 41-X transmits the transmission / reflection pattern 20d-X. The detection signal ABSX is detected according to the first light quantity based on the above.

  In FIG. 11, the light receiving elements 411-1 to 411-X, the power supply units 412-1 to 412-X, the resistors 413-1 to 413-X, and the amplifier units 414-1 to 414-X are respectively The configuration is the same as that of the light receiving element 411, the power supply unit 412, the resistor 413, and the amplifier unit 414 in the first embodiment, and a description thereof is omitted here.

  Each of the light receiving sensor units 42-1 to 42-X (second sensor unit) has the same configuration as the light receiving sensor unit 42 in the first embodiment, detects the pattern 20d, and emits light through the pattern 20d. The detection signals / ABS1 to / ABSX (second detection signals) are output in accordance with the second light quantity generated in step S2. The light receiving sensor units 42-1 to 42-X in this embodiment are each provided with one light receiving element 421 (421) instead of including a plurality of light receiving elements 421 as in the light receiving sensor unit 42 in the first embodiment. -1 to 421-X). Here, for example, the light receiving sensor unit 42-1 detects the detection signal / ABS1 according to the second light quantity based on the transmission / reflection pattern 20d-1, and the light reception sensor unit 42-X transmits the transmission / reflection pattern 20d-. The detection signal / ABSX is detected according to the second light quantity based on X.

  In FIG. 11, the light receiving elements 421-1 to 421-X, the power supply units 422-1 to 422-X, the resistors 423-1 to 423-X, and the amplifier units 424-1 to 424-X are respectively The configuration is the same as that of the light receiving element 421, the power supply unit 422, the resistor 423, and the amplifier unit 424 in the first embodiment, and a description thereof is omitted here.

The binarization units 60-1 to 60-X include detection signals ABS1 to ABSX output from the light receiving sensor units 41-1 to 41-X and detection signals / ABS1 output from the light receiving sensor units 42-1 to 42-X. The binarized signals DABS1 to DABSX corresponding to the pattern 20d are generated using .about. / ABSX as a differential signal. For example, the binarization unit 60-1 uses the detection signal ABS1 output from the light receiving sensor unit 41-1 and the detection signal / ABS1 output from the light receiving sensor unit 42-1 as differential signals, and the transmission / reflection pattern 20d-1 A binary signal DABS1 corresponding to is generated. Further, for example, the binarization unit 60-X uses the detection signal ABSX output from the light receiving sensor unit 41-X and the detection signal / ASX output from the light receiving sensor unit 42-X as differential signals, and the transmission / reflection pattern 20d. A binarized signal DABSX corresponding to -X is generated. The binarization units 60-1 to 60-X output the generated binarization signals DABS1 to DABS-X to the position detection unit 40a.
Each of the binarization units 60-1 to 60-X includes, for example, a comparator circuit (comparators 61-1 to 60-X) similar to the comparator 61 in the first embodiment. Here, the comparators 61-1 to 60-X have the same configuration as the comparator 61 in the first embodiment, and a description thereof will be omitted here.

  The position detector 40a detects position information (eg, angle information) of the rotor 6 based on the binarized signals DABS1 to DABSX generated by the binarizers 60-1 to 60-X. The position detection unit 40a generates a code corresponding to the gray code pattern in the pattern 20d based on the binarized signals DABS1 to DABSX, and generates absolute position information (eg, angle information) corresponding to the generated code. The position detection unit 40a outputs the generated absolute position information to, for example, a host device such as an external controller.

Next, the operation of the encoder 1d in the present embodiment will be described with reference to the drawings.
FIG. 12 is a diagram illustrating the operation of the encoder 1d in the present embodiment.
In FIG. 12, each graph shows a differential signal (detection signal ABS1, detection signal / ABS1), a binary signal DABS1, a differential signal (detection signal ABSX, detection signal) corresponding to the position in the rotation direction (detection direction). / ABSX) and the binarized signal DABSX. Here, the waveform W13 indicates the signal waveform of the differential signal (detection signal ABS1) output from the light receiving sensor unit 41-1, and the waveform W14 indicates the differential signal (detection signal / The signal waveform of ABS1) is shown. A waveform W15 indicates the binarized signal DABS1 output from the binarizing unit 60-1.

A waveform W16 indicates a signal waveform of a differential signal (detection signal ABSX) output from the light receiving sensor unit 41-X, and a waveform W17 indicates a differential signal (detection signal / ABSX) output from the light receiving sensor unit 42-X. ) Shows the signal waveform. A waveform W18 represents the binarized signal DABSX output from the binarization unit 60-X.
In FIG. 12, the transmission / reflection pattern 20d-1 and the transmission / reflection pattern 20d-X are formed by a combination of a transmission part 20T and a reflection part 20R.

In the present embodiment, the operations of the light receiving sensor units 41-1 to 41-X, the light receiving sensor units 42-1 to 42-X, and the binarizing units 60-1 to 60-X are the same as those in the first embodiment. The operation is the same as that of the sensor unit 41, the light receiving sensor unit 42, and the binarization unit 60.
For example, the light receiving sensor unit 41-1 detects the transmission / reflection pattern 20d-1, and outputs a detection signal ABS1 as indicated by the waveform W13 to the binarization unit 60-1. Here, the potential Vref indicates an intermediate potential of the change of the detection signal ABS1.
For example, the light receiving sensor unit 42-1 detects the transmission / reflection pattern 20d-1, and outputs a detection signal / ABS1 as indicated by the waveform W14 to the binarization unit 60-1.
For example, the comparator 61-1 of the binarization unit 60-1 uses the detection signal ABS1 output from the light receiving sensor unit 41-1 and the detection signal / ABS1 output from the light receiving sensor unit 42-1 as differential signals. A binary signal DABS1 corresponding to the transmission / reflection pattern 20d-1 as shown by the waveform W15 is generated.

Further, for example, the light receiving sensor unit 41-X detects the transmission / reflection pattern 20d-X, and outputs a detection signal ABS1 as indicated by the waveform W16 to the binarization unit 60-1. Here, the potential Vref indicates an intermediate potential of the change of the detection signal ABSX.
For example, the light receiving sensor unit 42-X detects the transmission / reflection pattern 20d-X, and outputs a detection signal / ABSX as indicated by the waveform W17 to the binarization unit 60-X.
For example, the comparator 61-X of the binarization unit 60-X uses the detection signal ABSX output from the light receiving sensor unit 41-X and the detection signal / ASX output from the light receiving sensor unit 42-X as differential signals. Then, a binary signal DABSX corresponding to the transmission / reflection pattern 20d-X as shown by the waveform W18 is generated.

  Here, in the conventional encoder, the margin (for example, noise margin) when generating the binarized signal is the voltage range MG1. On the other hand, in the encoder 1d in the present embodiment, a margin (for example, noise margin) when generating the binarized signal DABS1 is a voltage range MG2 that is wider than the voltage range MG1. Similarly, in the encoder 1d in the present embodiment, the margin (for example, noise margin) when generating the binarized signal DABSX is the voltage range MG2. As described above, the encoder 1d according to the present embodiment can widen the margin (for example, noise margin) when generating the binarized signals DABS1 to DABSX as compared with the case where the conventional fixed threshold voltage is used.

  Next, the position detector 40a detects position information (eg, angle information) of the rotor 6 based on the binarized signals DABS1 to DABSX generated by the binarizers 60-1 to 60-X. .

  As described above, the encoder 1d in the present embodiment includes the light receiving sensor units 41-1 to 41-X, the light receiving sensor units 42-1 to 42-X, and the binarization unit 60 similar to those in the first embodiment. -1 to 60-X. The encoder 1d in the present embodiment generates a differential signal similar to that in the first embodiment based on the multi-track pattern (transmission / reflection patterns 20d-1 to 20d-X) using the Gray code. The same effect as that of the first embodiment can be obtained. Therefore, the encoder 1d in the present embodiment can improve the reliability as in the first embodiment.

[Sixth Embodiment]
Next, a driving device (motor device, actuator) including the encoder 1 (1a to 1d) in the above-described embodiment will be described.
FIG. 13 is a schematic diagram of the drive device DR in the present embodiment. The drive device DR in the present embodiment includes a motor MTR that rotates the input shaft IAX, and an encoder 1 (1a to 1d) provided on the input shaft IAX (rotor). That is, the driving device DR includes an encoder 1 (1a to 1d) and a motor MTR (driving unit) that drives (moves) the input shaft IAX (driven body).

  The encoder 1 (1a to 1d) detects the rotational position (angular position) of the input shaft IAX (driven body), and uses the positional information including the rotational position as an encoder signal for a host controller that controls the driving device DR. Output. The host controller controls the driving device DR based on the encoder signal received from the encoder 1 (1a to 1d). Since the encoder 1 (1a to 1d) in the present embodiment can reduce erroneous detection of the rotational position of the input shaft IAX, the driving device DR in the present embodiment controls the position of the input shaft IAX of the motor MTR with high accuracy. be able to. Further, the driving device DR in the present embodiment can improve the reliability in position control.

[Seventh Embodiment]
Next, a robot apparatus including the driving device DR in the above-described embodiment will be described.
FIG. 14 is a diagram illustrating a configuration of a part (tip of a finger part of a hand robot) of a robot apparatus RBT including the driving apparatus DR (motor apparatus) described in the sixth embodiment as an example. The drive device DR described in the above embodiment may be used as a drive unit that drives the arm unit of the robot device RBT.

  As shown in FIG. 14, the robot apparatus RBT includes a terminal node portion 101, a middle node portion 102, and a joint portion 103, and the terminal node portion 101 and the middle node portion 102 are connected via the joint portion 103. It has become. The joint portion 103 is provided with a shaft support portion 103a and a shaft portion 103b. The shaft support portion 103 a is fixed to the middle joint portion 102. The shaft portion 103b is supported in a state of being fixed by the shaft support portion 103a.

  The end node portion 101 includes a connecting portion 101a and a gear 101b. The shaft portion 103b of the joint portion 103 is penetrated through the connecting portion 101a, and the end node portion 101 is rotatable with the shaft portion 103b as a rotation axis. The gear 101b is a bevel gear fixed to the connecting portion 101a. The connecting portion 101a rotates integrally with the gear 101b.

  The middle joint portion 102 includes a housing 102a and a driving device DR. As the driving device DR, the driving device DR described in the above embodiment can be used. The driving device DR is provided in the housing 102a. A rotating shaft member 104a is attached to the driving device DR. A gear 104b is provided at the tip of the rotating shaft member 104a. The gear 104b is a bevel gear fixed to the rotating shaft member 104a. The gear 104b is in mesh with the gear 101b. Note that a configuration in which a gear is directly formed on the rotating shaft member 104a may be employed.

  In the robot apparatus RBT configured as described above, the rotation shaft member 104a is rotated by the drive of the driving device DR, and the gear 104b is rotated integrally with the rotation shaft member 104a. The rotation of the gear 104b is transmitted to the gear 101b meshed with the gear 104b, and the gear 101b rotates. As the gear 101b rotates, the connecting portion 101a also rotates, whereby the end node portion 101 rotates about the shaft portion 103b.

  Thus, according to the present embodiment, it is possible to provide a robot apparatus RBT with high reliability in position control by mounting the drive apparatus DR that can improve the reliability in position control.

The present invention is not limited to the above embodiments, and can be modified without departing from the spirit of the present invention.
For example, in the first, second, fourth, and fifth embodiments, the substrate 7 (7a, 7c, 7d) has been described as being mounted with the light source unit 3 and the light receiving element 421 (411). The light source unit 3 and the light receiving element 421 (411) may be mounted on different substrates.

For example, FIG. 15 is a diagram illustrating a modification in the case where the light receiving element 421 is mounted on the substrate 7e and the light source unit 3 is not mounted on the substrate 7e in the first embodiment. As described above, the encoder 1 according to the first embodiment may be configured such that the light source unit 3 and the light receiving element 421 are mounted on different substrates.
For example, FIG. 16 is a diagram illustrating a modification in the case where the light receiving elements 421-1 to 421-3 are mounted on the substrate 7f and the light source unit 3 is not mounted on the substrate 7f in the fifth embodiment. As described above, the encoder 1d according to the fifth embodiment may be configured such that the light source unit 3 and the light receiving elements 421-1 to 421-3 are mounted on different substrates.
In this case, for example, even when the substrate 7e (7f) is a semiconductor substrate (semiconductor chip) and there is no mounting device capable of chip-on-chip bonding the chip of the light source unit 3, it is possible to use simple mounting means. The encoder 1 (1d) can be manufactured.

  In the fifth embodiment, the multitrack using the gray code is applied to the first embodiment. However, the multitrack using the gray code is used in the second to fourth embodiments. You may apply.

  In each of the above embodiments, the light source unit 3 has been described as being disposed at a position shifted in the short direction (eg, radial direction (X-axis direction)) with respect to the pattern 20 (20a to 20d). However, the present invention is not limited to this. For example, the light source unit 3 may be arranged so as to be shifted in the detection direction (circumferential direction) with respect to the pattern 20 (20a to 20d), or may be shifted in another direction (eg, oblique direction with respect to the detection direction). May be arranged. In addition, the length which shifts the light source part 3 with respect to the pattern 20 (20a-20d) is the distance from the light source part 3 to the code | symbol plate 2 (2a-2d), the light-receiving area of a detection element (411,421), and a light source part. It may be determined based on the three irradiation areas.

Further, in each of the above embodiments, the light source unit 3 has been described as emitting the irradiation light to the code plate 2 (2a to 2d) without going through the lens, but the code plate 2 (2a to 2d) through the lens. ) May emit the irradiation light.
In each of the above embodiments, the encoder 1 (1a to 1d) is a rotary encoder. However, each of the above embodiments is a linear encoder in which the code plate moves relative to the sensor unit. You may apply to.

  1, 1a, 1b, 1c, 1d ... encoder, 2, 2a, 2b, 2c, 2d, 2f ... code plate, 6 ... rotor, 7, 7a, 7b, 7c, 7d ... substrate, 20, 20a, 20b, 20c, 20d ... pattern, 20d-1, 20d-2, 20d-3 ... transmission reflection pattern, 21, 22, 22b ... reflection pattern, 21a, 21b, 22a ... transmission pattern, 20T, 21T, 22T ... transmission part, 20R , 21R, 22R ... reflective portion, 21NT, 22NT ... non-transmissive portion, 21NR, 22NR ... non-reflective portion, 40, 40a ... position detecting portion, 41, 42, 41-1, 42-1, 41-X, 42- X ... light receiving sensor unit, 60, 60-1, 60-X ... binarization unit, DR ... drive device, MTR ... motor, RBT ... robot device

Claims (15)

A light source unit for emitting irradiation light;
A sign plate having a pattern that indicates positional information of the driven body and that causes the irradiation light to generate a first light quantity and a second light quantity having an opposite phase obtained by inverting the first light quantity;
A first light receiving sensor unit that outputs a first detection signal according to the first light amount generated in the irradiation light through the pattern;
A second light receiving sensor unit that outputs a second detection signal according to the second light amount generated in the irradiation light through the pattern;
A binarization unit that generates a binarized signal corresponding to the position information using the first detection signal and the second detection signal as differential signals;
On the basis of the binary signal, Ru and a position detector for detecting the position information encoder. The pattern is
It is formed including a transmission part that transmits the irradiation light and a reflection part that reflects the irradiation light,
The first light receiving sensor unit outputs the first detection signal according to the first light amount generated in the light transmitted through the pattern,
The second light receiving sensor unit outputs the second detection signal according to the second light amount generated in the light reflected from the pattern.
Encoder according to 請 Motomeko 1. The pattern is
The position information is formed by a combination of the transmission part and the reflection part.
Encoder according to 請 Motomeko 2. The pattern is
A first pattern formed by a combination of the transmissive portion and a non-transmissive portion having a lower transmittance than the transmissive portion;
A second pattern formed by a combination of the reflective part and a non-reflective part having a lower reflectance than the reflective part,
Encoder according to 請 Motomeko 2. The pattern is
A first pattern for generating the first light amount;
A second pattern formed by an inverted pattern of the first pattern and generating the second light amount,
The first light receiving sensor unit outputs the first detection signal according to the first light amount based on the first pattern,
The second light receiving sensor unit outputs the second detection signal according to the second light amount based on the second pattern.
Encoder according to 請 Motomeko 1. The light source unit is arranged at a position away from the pattern in a short direction of the pattern different from a longitudinal direction of the pattern which is a detection direction of the position information.
Each of the first light receiving sensor unit and the second light receiving sensor unit is
The irradiation light emitted from the light source unit is disposed at a position where it enters through the pattern.
The encoder according to any one of claims 5 請 Motomeko 1. The light source unit and the second light receiving sensor unit are mounted on the same substrate.
The encoder according to any one of claims 6 請 Motomeko 1. The first light receiving sensor unit is arranged with the pattern interposed therebetween so as to face the light source unit.
The encoder according to any one of claims 7 請 Motomeko 1. Indicates the position information of the driven member, sign-board having a pattern that causes the irradiation light emitted and a second amount as the first light amount and the first amount antiphase obtained by inverting the light source unit . The pattern is
The transmission part that transmits the irradiation light and the reflection part that reflects the irradiation light are formed, the first light amount is generated in the light transmitted through the pattern, and the light reflected from the pattern is reflected in the light. Produce a second light quantity
Sign plate according to 請 Motomeko 9. The pattern is
The position information is formed by a combination of the transmission part and the reflection part.
Sign plate according to 請 Motomeko 1 0. The pattern is
A first pattern that is formed by a combination of the transmissive portion and a non-transmissive portion having a lower transmittance than the transmissive portion, and generates the first light amount;
Wherein a reflection portion, the formed by the combination of the non-reflective portion of low reflectivity than the reflection part, code plate according to 請 Motomeko 1 0 and a second pattern to produce a second light quantity. The pattern is
A first pattern for generating the first light amount;
Inverted is formed by the pattern, the sign plate according to 請 Motomeko 9 and a second pattern to produce a second quantity of the first pattern. A driven body;
A drive unit for moving the driven body;
Secured to said driven member, drive operated device comprising an encoder according the any one of claims 1 to claim 8 for detecting the position information of the driven body. Robot apparatus including the driving apparatus according to claim 1 4.

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