JP2016017884A - Sensor and sensor manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor or the like which more facilitates positioning of a generation part and a detection part.SOLUTION: A sensor includes: a generation part 41 which generates a prescribed detection object; a detection part 35 which detects the detection object generated by the generation part 41 across an area to be detected; and a substrate 50 in which the generation part 41 and the detection part 35 are provided. In the substrate 50, a first portion 51 in which the generation part 41 is provided and a second portion 52 in which the detection part 35 is provided are integrated.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a sensor and a method for manufacturing the sensor.

  As a configuration of a rotary encoder, a configuration is known in which a substrate provided with a light emitting element that emits light and a substrate provided with a light receiving element that detects light emitted from the light emitting element are housed in a casing of the rotary encoder. (For example, patent document 1).

JP 2001-027551 A

  However, in the rotary encoder described in Patent Document 1, since the light emitting element and the light receiving element exist on separate substrates, the relationship between the irradiation range of light emitted from the light emitting element and the light receiving range by the light receiving element in assembly is determined. There is a problem that the positioning of the position must be performed.

  The problem with the rotary encoder of Patent Document 1 as described above is not limited to the rotary encoder based on light detection, but a generation unit that emits a detection target (for example, light) and a detection unit that detects a detection target generated by the generation unit. Is a problem common to sensors provided on separate substrates.

  An object of the present invention is to provide a sensor and a method for manufacturing the sensor in which the positioning of the generation unit and the detection unit is easier.

  In order to achieve the above object, a sensor of the present invention includes a generation unit that generates a predetermined detection target, a detection unit that detects the detection target generated by the generation unit across a detection area, and the generation unit And a substrate on which the detection unit is provided, wherein the substrate includes a first part on which the generation unit is provided and a second part on which the detection unit is provided.

  Accordingly, since the first part provided with the generating part is not separated from the second part provided with the detecting part, the generating part and the detecting part can be positioned by a simple operation such as bending or bending the substrate. . Thus, according to the sensor of the present invention, it is easier to position the generating unit and the detecting unit.

  In the sensor of the present invention, the substrate is provided so that the first portion and the second portion are parallel to each other.

  Therefore, the positional relationship between the generator provided in the first portion and the detector provided in the second portion can be adjusted based on the relationship between the first portion and the second portion provided in parallel. For this reason, when the generator has directivity, it is easier to adjust the position for placing the detector in the detection target generation area by the generator and to design the position angle when the generator and detector are provided on the substrate. Become.

  In the sensor according to the aspect of the invention, the substrate includes a connection portion that connects the first portion and the second portion.

  Therefore, a region between the first portion and the second portion can be provided by the connecting portion. For this reason, the to-be-detected area | region between a generation | occurrence | production part and a detection part can be provided more easily.

  In the sensor according to the aspect of the invention, the connection unit includes a wiring connected to the generation unit or the detection unit.

  Therefore, the wiring connected to the generation unit or the detection unit and the connection unit can be integrated. For this reason, the board | substrate which has a connection part and the said wiring can be made more compact.

  In the sensor according to the aspect of the invention, the connection portion may be perpendicular to the extending direction of the connection portion between the first portion and the second portion, as compared with the first portion and the second portion. And the width in the direction along the plate surface of the substrate is small.

  Therefore, the area of the substrate can be further reduced as compared with the case where the width of the substrate including the first portion and the second portion sandwiching the connection portion is made uniform. For this reason, a board | substrate can be reduced more.

  In the sensor of the present invention, the substrate is bent at the boundary between the first portion and the connection portion and at the boundary between the second portion and the connection portion.

  Therefore, the detection region can be provided between the generation unit and the detection unit by bending the substrate. Further, the bent portion can be clarified.

  In the sensor according to the present invention, one of the first part and the second part is supported in a hollow state by the connecting portion, and the one is smaller than the other.

  Accordingly, it is possible to provide a detection region between the generation unit and the detection unit by supporting the hollow part of the first part or the second part by the connection part alone with the connection part. Moreover, the weight of the said one can be made lighter because the said one is smaller than the other. For this reason, in addition to making it possible to make requirements such as strength required for the connection portion easier, the center of gravity of the entire substrate can be brought closer to the other side which is the base. Therefore, the support by the connection portion can be realized more easily.

  In the sensor of the present invention, the substrate is bent into a shape in which the generation unit and the detection unit face each other.

  Therefore, handling in the case where the sensor is provided in the casing becomes easier, for example, a part of the substrate having the shape can be placed along a plane constituting the casing of a general machine.

  In the sensor of the present invention, the substrate is a flexible substrate.

  Therefore, after mounting the component including the generation unit and the detection unit on the substrate in a state where the first portion and the second portion are on the same plane, the substrate is processed to provide a detection region between the generation unit and the detection unit. This series of operations can be performed more easily.

  In the sensor according to the aspect of the invention, the substrate includes a harness part including wiring connected to the generation part and the detection part.

  Therefore, the wiring connected to the structure of the sensor including the generation unit and the detection unit can be collectively provided on the substrate including the harness unit. That is, by providing the harness portion, it is not necessary to individually draw out wiring from components (circuits or the like) that require wiring. For this reason, it is not necessary to handle the substrate and the wiring separately, and the sensor can be handled more easily.

  In the sensor according to the aspect of the invention, the detection unit detects a change in the detection target caused by a change in a physical quantity in the detection area.

  Therefore, an object that causes a change in physical quantity can be a sensing object by the sensor.

  In the sensor of the present invention, the detection target is an electromagnetic wave.

  Therefore, it is possible to detect a change in the detection area by a change in the electromagnetic wave.

  In the sensor of the present invention, the detection target is a magnetic force.

  Therefore, it is possible to detect a change in the detection area by a change in magnetic force.

  In the sensor of the present invention, the change in the physical quantity is due to the rotation of the rotating body existing in the detection area.

  Therefore, the rotational motion of the rotating body can be the target of sensing by the sensor.

  The sensor of the present invention is a rotary encoder.

  Therefore, according to the present invention, it is possible to detect an angular position such as a rotation angle of the rotation operation body connected to the rotary encoder.

  In the sensor of the present invention, the change in the physical quantity is due to the linear motion of the linear motion body existing in the detection area.

  Therefore, the linear motion of the linear motion body can be set as a sensing target by the sensor.

  The sensor of the present invention is an encoder.

  Therefore, the presence / absence and the operation position of the linear motion body connected to the encoder according to the present invention can be detected.

  The sensor of the present invention is a torque sensor.

  Therefore, torque can be measured according to the present invention.

  In the sensor of the present invention, the change in the physical quantity is due to a change in the concentration or amount of gas, liquid, or solid existing in the detection region.

  Therefore, a change in the concentration or amount of gas, liquid, or solid existing in the detection region can be a target of sensing by the sensor.

  In order to achieve the above object, a method for manufacturing a sensor according to the present invention includes: a first part provided with a generating unit that generates a predetermined detection target; and the detection target generated by the generating unit across a detection target region. A substrate integrated with a second portion provided with a detection portion to be detected is formed, the generation portion is provided in the first portion of the substrate, and the detection portion is provided in the second portion.

  Accordingly, since the first part provided with the generating part is not separated from the second part provided with the detecting part, the generating part and the detecting part can be positioned by a simple operation such as bending or bending the substrate. . Thus, according to the manufacturing method of the sensor of the present invention, positioning of the generation part and the detection part becomes easier.

  According to the sensor and the sensor manufacturing method of the present invention, it is possible to more easily position the generation unit and the detection unit.

FIG. 1 is a configuration diagram of a sensor according to the first embodiment. FIG. 2 is an external perspective view of the sensor according to the first embodiment. FIG. 3 is an explanatory diagram illustrating an example of the arrangement of the generation unit, the optical scale, and the detection unit. FIG. 4 is a block diagram of the optical encoder according to the first embodiment. FIG. 5 is an explanatory diagram illustrating an example of an optical scale pattern according to the first embodiment. FIG. 6 is a perspective view showing an example of the substrate. FIG. 7 is a plan view showing an example of the substrate before being bent. FIG. 8 is a perspective view showing an example of a stator body and a configuration provided on the body. FIG. 9 is a perspective view illustrating an example of a configuration provided in the chassis of the stator. FIG. 10 is a plan view showing an example of a substrate before circuit mounting. FIG. 11 is a diagram illustrating an example of assembling a stator for providing an optical scale in a detection area. FIG. 12 is an explanatory diagram for explaining an example of the detection unit according to the first embodiment. FIG. 13 is an explanatory diagram for explaining an example of the first light receiving unit of the detection unit according to the first embodiment. FIG. 14 is an explanatory diagram for describing an example of a third light receiving unit of the detection unit according to the first embodiment. FIG. 15 is an explanatory diagram for explaining separation of polarization components by the optical scale according to the first embodiment. FIG. 16 is an explanatory diagram for explaining separation of polarization components by the optical scale according to the first embodiment. FIG. 17 is an explanatory diagram for explaining separation of polarization components by the optical scale according to the first embodiment. FIG. 18 is a functional block diagram of the optical encoder according to the first embodiment. FIG. 19 is an explanatory diagram for explaining the rotation angle of the optical scale and the change in the light intensity of the polarization component of each light receiving unit according to the first embodiment. FIG. 20 is an explanatory diagram for explaining the relationship between the rotation angle of the optical scale and the Lissajous angle according to the first embodiment. FIG. 21 is a diagram for explaining the generation unit according to the first embodiment. FIG. 22 is an exploded perspective view for explaining main components of the torque sensor according to the second embodiment. FIG. 23 is an explanatory diagram illustrating the arrangement of the optical scale and the detection unit of the torque sensor according to the second embodiment. FIG. 24 is an explanatory diagram schematically illustrating the arrangement of the optical scale and the detection unit of the torque sensor according to the second embodiment. FIG. 25 is an explanatory diagram illustrating the arrangement of the optical scale and the detection unit of the torque sensor according to the second embodiment. FIG. 26 is a block diagram of the torque detection device according to the second embodiment. FIG. 27 is an explanatory diagram illustrating an example of a wire grid pattern of the optical scale according to the second embodiment. FIG. 28 is an explanatory diagram for describing a modification of the detection unit according to the second embodiment. FIG. 29 is an explanatory diagram for describing a modification of the detection unit according to the second embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

(Embodiment 1)
FIG. 1 is a configuration diagram of a sensor 31 according to the first embodiment. FIG. 2 is an external perspective view of the sensor 31 according to the first embodiment. FIG. 1 is a schematic cross-sectional view of FIG. FIG. 3 is an explanatory diagram illustrating an example of the arrangement of the generation unit 41, the optical scale 11, and the detection unit 35. FIG. 4 is a block diagram of the optical encoder 2 according to the first embodiment. FIG. 5 is an explanatory diagram illustrating an example of a pattern of the optical scale 11 according to the first embodiment. The sensor 31 includes a generation unit 41 that generates a detection target made of electromagnetic waves (for example, light), a detection unit 35 that detects a detection target generated by the generation unit 41 across a detection target region, and the generation unit 41 and the detection unit 35. The board | substrate 50 with which is provided. In the first embodiment, the sensor 31 further includes a shaft 12 connected to a rotating machine such as a motor, and a rotating body (optical scale 11) attached to an end of the shaft 12 and provided to be rotatable in a detection area. The rotor 10 has a stator 20. The detected area is an area between the generation unit 41 and the detection unit 35.

  FIG. 6 is a perspective view showing an example of the substrate 50. FIG. 7 is a plan view showing an example of the substrate 50 before being bent. In the substrate 50, the first portion 51 provided with the generating portion 41 and the second portion 52 provided with the detecting portion 35 are integrated. FIG. 8 is a perspective view illustrating an example of a structure provided on the body 21 and the body 21 of the stator 20. FIG. 9 is a perspective view illustrating an example of a configuration provided in the chassis 22 of the stator 20. FIG. 10 is a plan view showing an example of a substrate before circuit mounting. FIG. 11 is a diagram illustrating an example of the assembly of the stator 20 for providing the optical scale 11 in the detection area. For example, as shown in FIGS. 6 and 7, the substrate 50 is a single substrate including a semicircular arc-shaped first portion 51 and a circular second portion 52. The substrate 50 is made of, for example, a flexible printed circuit (FPC), and various circuits including the generator 41 and the detector 35 (for example, the circuits 60 to 62 shown in FIG. 6) are mounted thereon. More specifically, FPC uses an insulator made of, for example, a polyimide film or a photo solder resist film as a base film, and forms an adhesive layer and a conductor layer on the base film. A wiring board having flexibility in which a portion other than (including) is covered with an insulator. The conductor layer is made of an electrical conductor such as copper, and is provided with signal lines and power lines that are connected to components such as various circuits according to the pattern of the conductor layer. The specific configuration of the flexible substrate that can be employed in the present invention is not limited to this, and can be changed as appropriate. The circuits 60 to 62 constitute, for example, a preamplifier AMP, a differential arithmetic circuit DS, a filter circuit NR, a multiplier circuit AP, and the like shown in FIG.

  The substrate 50 has a connection portion 53 that connects the first portion 51 and the second portion 52. Specifically, for example, as shown in FIGS. 6 and 7, the connection portion 53 is between the first portion 51 and the second portion 52, and the outer peripheral portion of the arc of the first portion 51 and the second portion 52. It is provided to connect to the outer periphery of the arc.

  The connection unit 53 includes a wiring connected to the generation unit 41 (or the detection unit 35). In the first embodiment, the connection unit 53 includes a signal line and a power line connected to the generation unit 41. Specifically, the wiring of the connection portion 53 is provided as a signal line and a power line mounted on, for example, an FPC. In addition, although the circuit is not provided in the connection part 53 of Embodiment 1, components, such as a circuit, can also be provided in the connection part 53. FIG.

  As shown in FIGS. 6 and 7, the connecting portion 53 according to the first embodiment has a connecting portion 53 between the first portion 51 and the second portion 52 as compared with the first portion 51 and the second portion 52. The width in the direction perpendicular to the extending direction of the substrate 50 and along the plate surface of the substrate 50 is small.

  The substrate 50 includes a harness part 54 including wiring connected to the generation part 41 and the detection part 35. Specifically, as shown in FIGS. 6 and 7, for example, the harness portion 54 is provided so as to extend from the first portion 51 to the opposite side of the connection portion 53. The harness unit 54 includes a signal line and a power line that are connected to various circuits provided on the generation unit 41, the detection unit 35, and the substrate 50. Specifically, the wiring of the harness portion 54 is provided as, for example, a signal line and a power line mounted on the FPC. In the first embodiment, the wiring of the generation unit 41 is provided in the first portion 51, the connection portion 53, and the harness portion 54. The wiring of the detection unit 35 is provided in the second portion 52 and the harness portion 54.

  Moreover, the harness part 54 is connected with the connector CNT as shown, for example in FIG. The connector CNT is an interface that connects the sensor 31 and another device (for example, the arithmetic device 3). The sensor 31 is connected to the arithmetic device 3 via the connector CNT. That is, the harness portion 54 functions as a wiring that connects various circuits provided on the substrate 50 and another device (for example, the arithmetic device 3). In addition, you may provide components, such as a circuit, in the harness part 54. FIG.

  The substrate 50 is provided so that the first portion 51 and the second portion 52 are parallel to each other. Specifically, as illustrated in FIGS. 1 and 6, the substrate 50 is bent into a shape (a U-shape) in which the generation unit 41 and the detection unit 35 face each other. In the first embodiment, the substrate 50 is bent at the boundary 55 a between the first portion 51 and the connection portion 53 and at the boundary 55 b between the second portion 52 and the connection portion 53. That is, the substrate 50 of the first embodiment is bent so that the first portion 51 and the second portion 52 are perpendicular to the connection portion 53, and the first portion 51 and the second portion 52 are opposed to each other. Exist. Thereby, the 1st part 51 and the 2nd part 52 are provided in parallel, and the generation | occurrence | production part 41 and the detection part 35 oppose.

  The surface on the side where the generating unit 41 is provided in the first portion 51 and the surface on the side where the detecting unit 35 is provided in the second portion 52 are the same surface on the substrate 50. By providing the surface on the side where the generator 41 is provided and the surface on the side where the detector 35 is provided, the positional relationship between the generator 41 and the detector 35 is as shown in FIG. The detection target (for example, light) generated by the generation unit 41 has a positional relationship that can be detected by the detection unit 35. In addition, a region between the facing generation unit 41 and the detection unit 35 is a detection target region.

  One of the first portion 51 or the second portion 52 is supported hollowly by the connection portion 53, and one is smaller than the other. Specifically, for example, as shown in FIG. 6, the first portion 51 provided with the generating portion 41 is supported in a hollow manner by the connecting portion 53. In addition, as shown in FIGS. 6 and 7, the first portion 51 is smaller than the second portion 52. More specifically, the diameter of the arc-shaped first portion 51 in the first embodiment is substantially the same as the diameter of the circular second portion 52. However, the first portion 51 has a semicircular arc shape, and a semicircular cutout 51a is provided on the inner peripheral side of the semicircular FPC. For this reason, the area of the first portion 51 occupying the substrate 50 is smaller than the area of the second portion 52.

  The detection unit 35 detects a change in a detection target (for example, an electromagnetic wave such as light) caused by a change in a physical quantity in the detection region. The change in the physical quantity is due to, for example, rotation of a rotating body existing in the detection area. Specifically, for example, as shown in FIGS. 1 to 3, an optical scale 11 of the rotor 10 is provided in the detection region. The sensor 31 according to the first embodiment is a sensor that performs output according to a change in the detection result of the detection target due to the rotation of the optical scale 11 as a rotating body. That is, the sensor 31 according to the first embodiment functions as a rotary encoder that detects the angular position of the rotary driving body connected to transmit the rotational operation to the rotor 10.

  The rotor 10 has an optical scale 11 that is a disk-shaped (or polygonal) member shown in FIG. The optical scale 11 is made of, for example, silicon, glass, a polymer material, or the like. The optical scale 11 may be annular or hollow. The optical scale 11 shown in FIG. 5 has a signal track T1 on one plate surface. The rotor 10 has a shaft 12 attached to the other plate surface with respect to the plate surface to which the optical scale 11 is attached. Even if the optical scale 11 is tilted, it does not affect the polarization separation function when the tilt angle is small. That is, even if the optical scale 11 is inclined with respect to a plane orthogonal to the rotation center Zr, it functions as a polarization separation element.

  The stator 20 is made of a light-shielding member that surrounds the bearings 26 a and 26 b, the shaft 12, the optical scale 11 attached to the end of the shaft 12, and the detection unit 35. For this reason, external optical noise can be suppressed inside the stator 20. As shown in FIGS. 8 and 9, the stator 20 includes a body 21, a chassis 22, and a cover 23. The body 21 rotatably supports the shaft 12 via bearings 26a and 26b. The inner periphery of the body 21 is fixed to the outer rings of the bearings 26a and 26b, and the outer periphery of the shaft 12 is fixed to the inner rings of the bearings 26a and 26b. When the shaft 12 is rotated by rotation from a rotating machine such as a motor, the optical scale 11 is rotated about the rotation center Zr in conjunction with the shaft 12. The body 21 has an opening 21 a for attaching the chassis 22 provided with the substrate 50 to the body 21. The chassis 22 supports the substrate 50 by contacting at least a part of a surface (back surface) opposite to the side where the detection unit 35 is provided in the second portion 52 of the substrate 50. Specifically, an integrated circuit (for example, an IC of a QFN package) as a component constituting the sensor is provided on the back surface of the substrate 50. The chassis 22 supports the substrate 50 by covering the integrated circuit on the back surface from the outside and contacting the outer peripheral portion of the back surface of the substrate 50. The connection portion 53 of the substrate 50 bent in a U-shape is positioned so as to stand up from the second portion 52 supported by the chassis 22. As described above, in the first embodiment, the substrate 50 is fixed to the chassis 22. The cover 23 is a member that forms a part of the cylindrical outer peripheral surface of the stator 20. The cover 23 is provided on the opening 21 a side of the body 21, that is, on the opposite side of the notch 21 b where the harness portion 54 extends from the chassis 22. In the state where the body 21 and the chassis 22 are assembled, the cover 23 is further assembled so as to cover the opening 21a, so that the body 21, the chassis 22 and the cover 23 form a cylindrical stator 20, and the stator 20 The inside is shielded from external light noise.

  When the shaft 12 of the rotor 10 described above rotates, the optical scale 11 moves relative to the detection unit 35 in the R direction, for example, as shown in FIG. As a result, the signal track T1 of the optical scale 11 moves relative to the detector 35. In the optical scale 11, the polarization direction Pm of the polarizer in the plane is in a predetermined direction, and the polarization direction Pm is changed by rotation. The detecting unit 35 can receive the incident light (transmitted light) 73 that is incident upon the light source light 71 of the generating unit 41 transmitted through the optical scale 11 and can read the signal track T1 of the optical scale 11 shown in FIG. .

  The optical encoder 2 includes the sensor 31 and the arithmetic device 3 described above, and the sensor 31 and the arithmetic device 3 are connected as shown in FIG. The arithmetic device 3 is connected to a control unit 5 of a rotating machine such as a motor.

  In the optical encoder 2, the detection unit 35 detects incident light 73 that is incident on the optical scale 11 through the light source light 71. The calculation device 3 calculates the relative position between the rotor 10 of the sensor 31 and the detection unit 35 from the detection signal of the detection unit 35, and outputs the relative position information as a control signal to the control unit 5 of the rotary machine such as a motor. .

  The arithmetic device 3 is a computer such as a personal computer (PC), for example, and includes an input interface 4a, an output interface 4b, a CPU (Central Processing Unit) 4c, a ROM (Read Only Memory) 4d, and a RAM (Random Access Memory). 4e and an internal storage device 4f. The input interface 4a, output interface 4b, CPU 4c, ROM 4d, RAM 4e, and internal storage device 4f are connected by an internal bus. Note that the arithmetic device 3 may be configured by a dedicated processing circuit.

  The input interface 4a receives an input signal from the detection unit 35 of the sensor 31 and outputs it to the CPU 4c. The output interface 4 b receives a control signal from the CPU 4 c and outputs it to the control unit 5.

  A program such as BIOS (Basic Input Output System) is stored in the ROM 4d. The internal storage device 4f is, for example, an HDD (Hard Disk Drive), a flash memory, or the like, and stores an operating system program and application programs. The CPU 4c implements various functions by executing programs stored in the ROM 4d and the internal storage device 4f while using the RAM 4e as a work area.

  The internal storage device 4f stores a database in which the polarization direction Pm of the optical scale 11 and the output of the detection unit 35 are associated with each other. Alternatively, the internal storage device 4f stores a database in which a value of distance D described later is associated with position information of the optical scale 11.

  In the signal track T1 shown in FIG. 5, an array of fine metal wires (wires) g called a wire grid pattern is formed on the optical scale 11 shown in FIG. The optical scale 11 linearly arranges adjacent fine metal wires g as signal tracks T1 in parallel. For this reason, the optical scale 11 has the same polarization axis regardless of the position where the light source light 71 is irradiated, and the polarization direction of the polarizer in the plane is in one direction.

  In addition, the optical scale 11 having the fine metal wires g called wire grid patterns can improve heat resistance as compared with a light-induced polarizing plate. In addition, since the optical scale 11 is a line pattern that does not have a portion that intersects locally, the optical scale 11 can be highly accurate and have few errors. Moreover, since the optical scale 11 can be stably manufactured by batch exposure or nanoimprint technology, the optical scale 11 can be made highly accurate and less error-prone. The optical scale 11 may be a light-induced polarizing plate.

  The plurality of fine metal wires g are arranged without intersecting. Between adjacent metal fine wires g is a transmission region d through which all or part of the light source light 71 can be transmitted. When the width of the fine metal wire g and the interval between the adjacent fine metal wires g, that is, the width of the fine metal wire g and the width of the transmission region d are sufficiently smaller than the wavelength of the light source light 71 of the generating unit 41, the optical scale 11 71 incident light 73 can be polarized and separated. For this reason, the optical scale 11 has a polarizer in which the in-plane polarization direction Pm is uniform. In the rotating circumferential direction of the optical scale 11, the polarization axis of the incident light 73 incident on the detection unit 35 changes according to the rotation of the optical scale 11. In the first embodiment, the change of the polarization axis repeats the increase / decrease twice for one rotation of the optical scale 11.

  The optical scale 11 does not need to be finely divided into segments having different polarization directions. And since the optical scale 11 has the uniform polarization direction Pm, there is no boundary of the area | region from which the polarization direction Pm differs, and it can suppress disorder of the polarization state of the incident light 73 by this boundary. The optical encoder 2 of Embodiment 1 can reduce the possibility of causing false detection or noise.

  FIG. 12 is an explanatory diagram for explaining an example of the detection unit 35 according to the first embodiment. FIG. 13 is an explanatory diagram for explaining an example of the first light receiving unit PD1 of the detection unit 35 according to the first embodiment. FIG. 14 is an explanatory diagram for explaining an example of the third light receiver PD3 of the detector 35 according to the first embodiment. As shown in FIGS. 3 and 12, the detection unit 35 includes a first light receiving unit PD1 having a polarizing layer PP1, a second light receiving unit PD2 having a polarizing layer PP2, and a polarization on the surface 30b of the unit base 30. A third light receiving part PD3 having a layer PP3 and a fourth light receiving part PD4 having a polarizing layer PP4 are included. As shown in FIG. 12, the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4 are equidistant from the arrangement center S0 of the surface 30b of the unit base member 30 in plan view. Has been placed.

  The generating unit 41 is, for example, a light emitting diode or a semiconductor laser light source. As shown in FIG. 3, the light source light 71 emitted from the generation unit 41 passes through the optical scale 11 described above, and enters the polarizing layer PP1, the polarizing layer PP2, the polarizing layer PP3, and the polarizing layer PP4 as the incident light 73. The light passes through and enters the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4.

  As shown in FIG. 3, it is preferable that the distances from the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4 to the arrangement center S0 are equal. With this structure, it is possible to reduce the calculation load on the CPU 4c which is the calculation means.

  Further, the first light receiving part PD1 is arranged at a point-symmetrical position with respect to the third light receiving part PD3 via the arrangement center S0, and the second light receiving part PD2 is point-symmetrical with the fourth light receiving part PD4 via the arrangement center S0. Is arranged. The first light receiving unit PD1 is arranged at a distance W from the third light receiving unit PD3 via the arrangement center S0, and the second light receiving unit PD2 is arranged at a distance W from the fourth light receiving unit PD4 through the arrangement center S0. Has been. Note that there is a width w that the first light receiving part PD1, the third light receiving part PD3, the second light receiving part PD2, and the fourth light receiving part PD4 have, and there is a restriction that the distance W is not smaller than the width 2w. In the first embodiment, the virtual axis on the surface 30b of the unit base material 30 passing through the first light receiving part PD1, the placement center S0, and the third light receiving part PD3 is defined as the x axis, and the second light receiving part PD2, the placement center S0, and the first light receiving part PD2. The virtual axis on the surface 30b of the unit base material 30 passing through the four light receiving parts PD4 is taken as the y axis. In FIG. 12, the x axis is orthogonal to the y axis on the surface 30 b of the unit substrate 30. As shown in FIG. 3, let D be the distance between the exit surface of the generator 41 and the arrangement center S0. The xy plane formed by the x-axis and the y-axis is orthogonal to the z-axis connecting the emission surface of the generation unit 41 and the arrangement center S0.

  As shown in FIG. 3, each of the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4 is arranged around the generating part 41 when viewed in a plan view from the z-axis direction. Has been. It is preferable that the distances from the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4 to the arrangement center S0 are equal. With this structure, it is possible to reduce the calculation load on the CPU 4c which is the calculation means.

  As shown in FIG. 13, the first light receiving portion PD1 includes a silicon substrate 34, a light receiving portion 37, and a first polarizing layer 39a. As shown in FIG. 14, the third light receiving portion PD3 includes a silicon substrate 34, a light receiving portion 37, and a second polarizing layer 39b. For example, the silicon substrate 34 is an n-type semiconductor, the light receiving portion 37 is a p-type semiconductor, and a photodiode formed by a PN junction with the silicon substrate 34 and the light receiving portion 37 can be configured. The first polarizing layer 39a and the second polarizing layer 39b can be formed of a light-induced polarizing layer or a wire grid pattern in which fine metal wires are arranged in parallel. The first polarizing layer 39a separates the incident light 73 incident from the light source light 71 into the optical scale 11 shown in FIG. 3 in the first polarization direction, and the second polarizing layer 39b separates the incident light 73 into the second polarized light. Separate in direction. It is preferable that the polarization axis of the first separated light and the polarization axis of the second separated light are relatively different by 90 °. With this configuration, the CPU 4c of the arithmetic device 3 can easily calculate the polarization angle.

  Similarly, with reference to FIGS. 13 and 14, the second light receiving portion PD2 includes a silicon substrate 34, a light receiving portion 37, and a first polarizing layer 39a. As shown in FIG. 14, the fourth light receiving portion PD4 includes a silicon substrate 34, a light receiving portion 37, and a second polarizing layer 39b. For example, the silicon substrate 34 is an n-type semiconductor, the light receiving portion 37 is a p-type semiconductor, and a photodiode formed by a PN junction with the silicon substrate 34 and the light receiving portion 37 can be configured. The first polarizing layer 39a and the second polarizing layer 39b can be formed of a light-induced polarizing layer or a wire grid pattern in which fine metal wires are arranged in parallel. The first polarizing layer 39a separates the incident light 73 incident from the light source light 71 into the optical scale 11 shown in FIG. 3 in the first polarization direction, and the second polarizing layer 39b separates the incident light 73 into the second polarized light. Separate in direction. It is preferable that the polarization axis of the first separated light and the polarization axis of the second separated light are relatively different by 90 °. With this configuration, the CPU 4c of the arithmetic device 3 can easily calculate the polarization angle.

  The first light receiving unit PD1, the second light receiving unit PD2, the third light receiving unit PD3, and the fourth light receiving unit PD4 receive the incident light 73 through the polarization layers PP1, PP2, PP3, and PP4 that separate the different polarization directions, respectively. . For this reason, it is preferable that the polarization axis separated by the polarizing layer PP1 and the polarization axis separated by the polarizing layer PP2 are relatively different by 45 °. It is preferable that the polarization axis separated by the polarizing layer PP2 and the polarization axis separated by the polarizing layer PP3 are relatively different by 45 °. It is preferable that the polarization axis separated by the polarizing layer PP3 and the polarization axis separated by the polarizing layer PP4 are relatively different by 45 °. It is preferable that the polarization axis separated by the polarization layer PP4 and the polarization axis separated by the polarization layer PP1 are relatively different by 45 °. With this configuration, the CPU 4c of the arithmetic device 3 can easily calculate the polarization angle.

  FIGS. 15, 16, and 17 are explanatory diagrams for explaining the separation of polarization components by the optical scale 11 according to the first embodiment. As shown in FIG. 15, incident light polarized in the polarization direction Pm is incident by the signal track T <b> 1 of the optical scale 11. In FIG. 15, the sensing range includes foreign matter D1 and foreign matter D2. The polarization direction Pm of incident light can be expressed by the light intensity PI (−) of the first polarization direction component and the light intensity PI (+) of the second polarization direction component. As described above, the first polarization direction and the second polarization direction are preferably different from each other by 90 °, and are, for example, a + 45 ° component and a −45 ° component with respect to the reference direction. . 15, 16 and 17, the axial direction of the wire grid is shown parallel to the paper surface. However, even if the wire grid is inclined at the same angle with respect to the paper surface, it is polarized when the inclination angle is small. The separation function is not affected. That is, even if the optical scale 11 is inclined with respect to the rotation axis, it functions as a polarization separation element.

  As shown in FIG. 16, the first light receiving unit PD1 detects incident light through the first polarizing layer 39a that separates the incident light in the first polarization direction, and thus the light intensity PI (− of the component in the first polarization direction). ) Is detected. As shown in FIG. 17, the third light receiving unit PD3 detects incident light via the second polarizing layer 39b that separates the incident light in the second polarization direction, and thus the light intensity PI (+ of the component in the second polarization direction) ) Is detected. Similarly, as shown in FIG. 16, since the second light receiving unit PD2 detects incident light through the first polarizing layer 39a that separates the incident light in the first polarization direction, the light intensity of the component in the first polarization direction is detected. PI (-) is detected. As shown in FIG. 17, the fourth light receiving unit PD4 detects incident light through the second polarizing layer 39b that separates the incident light in the second polarization direction, and thus the light intensity PI (+ of the component in the second polarization direction) ) Is detected.

  FIG. 18 is a functional block diagram of the optical encoder 2 according to the first embodiment. FIG. 19 is an explanatory diagram for explaining the rotation angle of the optical scale 11 according to the first embodiment and the light intensity change of the polarization component of each light receiving unit. As shown in FIG. 18, the generator 41 emits light based on the reference signal and irradiates the optical scale 11 with the light source light 71. Incident light 73 that is transmitted light is received by the detector 35. The differential arithmetic circuit DS performs differential arithmetic processing using the detection signal output from the detection unit 35 and amplified by the preamplifier AMP. The preamplifier AMP can be omitted according to the output level of the detection unit 35.

  The differential arithmetic circuit DS detects the light intensity PI (−) of the first polarization direction component (first separation light) and the second polarization direction component (second separation light), which are detection signals of the detection unit 35. ) Of the light intensity PI (+). The respective outputs of the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4 corresponding to the light intensity PI (−) and the light intensity PI (+) are, for example, As shown in FIG. 19, the light intensities I1, I2, I3, and I4 are out of phase according to the rotation of the optical scale 11.

The differential arithmetic circuit DS calculates the optical intensity from the light intensity PI (−) of the component in the first polarization direction and the light intensity PI (+) of the component in the second polarization direction according to the expressions (1) and (2). The differential signals Vc and Vs depending on the rotation of the scale 11 are calculated.
Vc = (I1-I3) / (I1 + I3) (1)
Vs = (I2-I4) / (I2 + I4) (2)

  In this way, the differential operation circuit DS calculates the light intensity sum [I1 + I3] and the light intensity difference [I1-I3] based on the light intensity I1 and the light intensity I3, and the light intensity difference [I1 -I3] is divided by the sum of light intensities [I1 + I3] to calculate a differential signal Vc. Further, the differential operation circuit DS calculates the light intensity sum [I2 + I4] and the light intensity difference [I2-I4] based on the light intensity I2 and the light intensity I4, and the light intensity difference [I2-I4]. ] Is calculated by dividing the light intensity by the sum [I2 + I4] of the light intensity. The differential signals Vc and Vs calculated by the equations (1) and (2) do not include a parameter affected by the light intensity of the light source light 71, and the output of the sensor 31 is output from the detection unit 35 and the optical signal. The influence of the distance from the scale 11 and the variation in the light intensity of the generation unit 41 can be reduced. The differential signals Vc and Vs are a function of the rotation angle (hereinafter referred to as the polarization angle) β of the polarization axis of the optical scale 11 that is the rotation angle of the optical scale 11. However, when the automatic power control (APC) for controlling the light amount of the light source provided in the generation unit 41 to be constant is provided, the above division is not necessary.

  As shown in FIG. 18, the differential signals Vc and Vs are input to the filter circuit NR and noise is removed. Next, the multiplication circuit AP can calculate the Lissajous pattern shown in FIG. 20 from the differential signals Vc and Vs, and can specify the absolute angle of the rotation angle of the rotor 10 rotated from the initial position. Since the differential signals Vc and Vs are differential signals having a phase shift of λ / 4, a Lissajous pattern with the cosine curve of the differential signal Vc on the horizontal axis and the sine curve of the differential signal Vs on the vertical axis is used. The Lissajous angle is determined according to the calculation and the rotation angle. For example, the Lissajous pattern shown in FIG. 20 makes two revolutions when the rotor 10 makes one revolution. The arithmetic device 3 has a function of storing whether the rotation position of the optical scale 11 is in the range of 0 ° or more and less than 180 ° or in the range of 180 ° or more and less than 360 °. Thereby, the optical encoder 2 can be an absolute encoder capable of calculating the absolute position of the rotor 10.

  FIG. 21 is a diagram for explaining the generation unit 41 according to the first embodiment. The generator 41 shown in FIG. 21 is a package of a light source such as a light emitting diode, a laser light source such as a vertical cavity surface emitting laser, and a light emitting device 41U such as a filament. The light emitting device 41U uses a surface emitting light source. The generation unit 41 includes a base substrate 41F, a through conductive layer 41H embedded in the through hole SH, an external electrode 41P electrically connected to the through conductive layer 41H, and a light emitting device 41U mounted on the base substrate 41F. A bonding wire 41W that electrically connects the light emitting device 41U and the through conductive layer 41H, a sealing resin 41M that protects the light emitting device 41U, and a light shielding film 41R are provided.

  The light-shielding film 41R of the generating unit 41 has a function of a diaphragm for the light source light 71 that narrows the light source light 71 emitted from the light emitting device 41U to the range of the emission surface 41T. The exit surface 41T has no lens surface, and the light distribution of the light source light 71 shows a light distribution of a predetermined angle 2θo with respect to the cross section of the exit surface 41T. FIG. 23 is an explanatory diagram for explaining the position of the light receiving unit within a uniform range of the light distribution from the generation unit 41 of the detection unit 35 according to the first embodiment. The angle θo of the light distribution depends on the generator 41. The angle θo is 45 °, for example, but the angle can be made larger or smaller than this.

  The sensor 31 according to the first embodiment can use the generation unit 41 without a lens. The SN ratio can be improved by bringing the distance D between the emission surface of the generation unit 41 and the arrangement center S0 (detection unit 35) closer. The distance W to each of the first light receiving part PD1, the second light receiving part PD2, the third light receiving part PD3, and the fourth light receiving part PD4 can be arranged within a range where light can be received by reducing the influence of light diffused by the generating part 41. Become. For this reason, the measurement accuracy of the sensor 31 and the optical encoder 2 is improved. Of course, the generating part 41 with a lens may be used.

  Next, a method for manufacturing the sensor 31 will be described. First, the board | substrate 50 with which the 1st part 51 in which the generation | occurrence | production part 41 is provided and the 2nd part 52 in which the detection part 35 is provided is formed. Specifically, for example, as shown in FIG. 10, a semicircular arc-shaped first portion 51, a circular second portion 52, a connection portion 53 that connects the first portion 51 and the second portion 52, An FPC having a harness portion 54 extending from the first portion 51 to the opposite side of the connection portion 53 is formed. In this step, wiring such as signal lines and power lines connected to various circuits mounted on the substrate 50 in a later step is formed in the FPC.

  Next, various circuits constituting the sensor are provided on the substrate 50. Specifically, as illustrated in FIG. 7, the generation unit 41 is provided in the first portion 51 of the substrate 50, and the detection unit 35 is provided in the second portion 52 of the substrate 50. In addition to this, various components constituting the sensor are provided in this step in accordance with the wiring provided in the previous step.

  Next, the substrate 50 is bent so that the generation unit 41 and the detection unit 35 face each other. Specifically, for example, as shown in FIG. 6, the first portion 51 and the second portion 52 are bent in a U shape so as to be parallel.

  Then, the process according to the structure which changes a physical quantity in a to-be-detected area | region is passed. In the case of the sensor 31 according to the first embodiment, for example, on the basis of a predetermined plane, the first portion 51 and the second portion 52 of the bent substrate 50 and the plate surface of the optical scale 11 are set along the predetermined plane. . In this state, by moving at least one of the substrate 50 and the stator 20 having the optical scale 11 in a direction along the predetermined plane, the optical scale 11 is provided in the detection area. Specifically, for example, an opening through which the substrate 50 can be inserted in a direction along the plate surface of the optical scale 11 is provided at the position where the optical scale 11 is provided on the cylindrical outer peripheral surface of the stator 20. The optical scale 11 is provided in the detection area by the substrate 50 entering the part. In this case, the board | substrate 50 approachs by being inserted from the harness part 54 side with respect to an opening part. Further, a semicircular arc-shaped first portion 51 enters the side of the optical scale 11 where the rotor 10 extends, and a circular second portion 52 extends on the side of the optical scale 11 where the rotor 10 does not extend. enter in. More specifically, as shown in FIG. 11, the chassis 22 to which the second portion 52 is fixed and the body 21 on which the rotor 10 is rotatably provided include a first portion 51, a second portion 52, and an optical device. It is assumed that the scale 11 is substantially parallel and the optical scale 11 is positioned in the detection area between the first portion 51 and the second portion 52. That is, the first portion 51, the second portion 52, and the optical scale 11 are in a positional relationship along a predetermined plane. With this positional relationship, the body 21 and the chassis 22 are assembled by bringing the body 21 and the chassis 22 into close contact with each other along a predetermined plane so that the chassis 22 enters from the opening 21a of the body 21. Thereby, the optical scale 11 is provided in the detection area. The harness portion 54 extends from a cutout portion 21 b provided on the opposite side of the opening 21 a of the body 21. Thereafter, the cover 23 is attached so as to cover the opening 21 a of the body 21. In FIG. 11, illustration of some circuits such as the detection unit 35 is omitted, but in practice, various circuits including the detection unit 35 have already been mounted. The chassis 22 and the cover 23 may be integrated.

  As described above, according to the first embodiment, the first portion 51 provided with the generating unit 41 and the second portion 52 provided with the detecting unit 35 are not separated, and thus the substrate 50 can be simply bent or curved. The generation unit 41 and the detection unit 35 can be positioned by a simple operation. Thus, according to the first embodiment, the positioning of the generation unit 41 and the detection unit 35 becomes easier.

  In addition, since the first portion 51 and the second portion 52 are provided in parallel, the positional relationship between the generation unit 41 provided in the first portion 51 and the detection unit 35 provided in the second portion 52 is determined. Adjustment can be made based on the relationship between the first portion 51 and the second portion 52 provided in parallel. For this reason, when the generation unit 41 has directivity, the position adjustment for placing the detection unit 35 in the generation region of the detection target by the generation unit 41 and the position angle when the generation unit 41 and the detection unit 35 are provided on the substrate are related. Design becomes easier.

  In addition, a region between the first portion 51 and the second portion 52 can be provided by the connection portion 53. For this reason, the detection area between the generation unit 41 and the detection unit 35 can be provided more easily.

  Moreover, since the connection part 53 has the wiring connected to the generation | occurrence | production part 41, the wiring connected to the generation | occurrence | production part 41 and the connection part 53 can be integrated. For this reason, the board | substrate which has the connection part 53 and the said wiring can be made more compact.

  Further, since the width of the connection portion 53 is smaller than that of the first portion 51 and the second portion 52, the width of the substrate including the first portion 51 and the second portion 52 sandwiching the connection portion 53 is made uniform. Compared to the case, the area of the substrate can be made smaller. For this reason, a board | substrate can be reduced more.

  Further, the substrate is bent at the boundary 55a between the first portion 51 and the connection portion 53 and at the boundary 55b between the second portion 52 and the connection portion 53, so that the substrate 41 is bent between the generation portion 41 and the detection portion 35. A detection area can be provided. Further, the bent portion can be clarified.

  Further, since the first portion 51 is supported hollow by the connecting portion 53 and the first portion 51 is smaller than the second portion 52, the first portion 51 is supported hollow by the connecting portion 53 alone, and the generating portion It is possible to provide a detection area between 41 and the detection unit 35. Further, since the first portion 51 is smaller than the second portion 52, the weight of the first portion 51 can be further reduced. For this reason, in addition to making it possible to make requirements such as strength required for the connection portion 53 easier, it is possible to bring the center of gravity of the entire substrate closer to the second portion 52 side that is the base. Therefore, the support by the connecting portion 53 can be realized more easily.

  Further, the substrate is bent into a shape (for example, a U-shape) in which the generation unit and the detection unit are opposed to each other, so that a part of the substrate 50 (for example, the first surface of the chassis 22) 2 part 52 etc.) can be arranged, and handling when providing a sensor in a case becomes easier.

  Further, since the substrate is a flexible substrate, the generator 41 and the detector 35 are mounted after mounting the component including the generator 41 and the detector 35 on the substrate in a state where the first portion 51 and the second portion 52 are on the same plane. A series of operations of processing the substrate to provide the detection area between the two can be performed more easily.

  Further, the wiring board connected to the configuration of the sensor 31 including the generation unit 41 and the detection unit 35 is collectively provided by providing the harness unit 54 including the wiring connected to the generation unit 41 and the detection unit 35 on the substrate. be able to. That is, by providing the harness portion 54, it is not necessary to individually draw out wiring from components (circuits or the like) that require wiring. For this reason, it is not necessary to handle the substrate and the wiring separately, and the sensor can be handled more easily.

  Moreover, the detection part 35 detects the change of the detection target which arises by the change of the physical quantity in a to-be-detected area | region, and can make the target which produces the change of a physical quantity into the object of the sensing by a sensor.

  Further, since the detection target is an electromagnetic wave (for example, light), a change in the detection region can be detected by a change in the electromagnetic wave.

  Further, since the change in the physical quantity is caused by the rotation of the rotating body (for example, the optical scale 11) existing in the detection region, the rotational motion of the rotating body can be set as a sensing target by the sensor.

  Further, since the sensor functions as a rotary encoder, it is possible to detect an angular position such as a rotation angle of a rotation operation body connected to the sensor.

  The positional relationship between the first portion 51 and the second portion 52 may be reversed. That is, the generator 41 and the first part 51 may be provided on the chassis 22 side, and the detection part 35 and the second part 52 may be provided on the side supported by the connection part 53 so as to sandwich the detection area.

  Moreover, the 1st part 51 and the 2nd part 52 do not need to be parallel. The relationship between the first part 51 and the second part 52 is that a detection area can be provided between the generation part 41 and the detection part 35, and the detection target generated by the generation part 41 provided in the first part 51. Can be detected by the detection unit 35 provided in the second portion 52, and the detailed arrangement of the first portion 51 and the second portion 52 can be appropriately changed.

  The connection part 53 does not need to have wiring. In this case, the connection part 53 supports either the 1st part 51 or the 2nd part 52 in hollow, for example. Moreover, it is not essential that the said one is smaller than the other. The first portion 51 and the second portion 52 may be the same size, or the side supported by the connection portion 53 may be large. In addition, the stator 20 or the like may have a support portion for supporting at least one of the connection portion 53 and the first portion 51 in the first embodiment. Moreover, you may provide the structure (For example, latching parts, such as an adhesive agent, a tape, a processus | protrusion, etc.) for fixing at least one of the connection part 53 and the 1st part 51 in Embodiment 1 to this support part.

  The bending position of the substrate 50 is not limited to the boundary 55 a between the first portion 51 and the connection portion 53 and the boundary 55 b between the second portion 52 and the connection portion 53. For example, a connecting portion 53 including a fold may be provided between the first portion 51 and the second portion 52 separately. Further, the bending of the substrate 50 is not essential. For example, the generation unit 41 and the detection unit 35 may be opposed to each other by bending the substrate 50 in a U shape.

  The substrate 50 is not limited to a flexible substrate. In the substrate of the present invention, a detection region can be provided between the generation unit 41 and the detection unit 35, and a detection target generated by the generation unit 41 provided in the first portion 51 is provided in the second portion 52. Any substrate can be used as long as the first portion 51 and the second portion 52 are integrated with each other. For example, a substrate made of a material that can be bent or bent by a process such as heating is adopted, and the process is applied to a part between the first part and the second part (for example, a connection part) and bent. Alternatively, the first portion and the second portion may be opposed to each other by being curved. Moreover, you may employ | adopt the board | substrate which has both a part which is hard to deform | transform, and a part which is easy to deform | transform like a rigid flexible substrate. In this case, the first part and the second part are used by using the part that is not easily deformed and the part that is easily deformed as a part between the first part and the second part (for example, a connection part). The second portion can be opposed.

  The harness portion 54 may be omitted as appropriate. Moreover, the extension part which functions as a harness part may be two or more.

  The specific pattern of the signal track T1 of the optical scale 11 and the pattern of the polarizing layers PP1 to PP4 provided in the detector 35 can be changed as appropriate. Such a pattern is determined in consideration of the relationship between the pattern of a configuration (for example, the optical scale 11) provided in the detection region and causing polarized light, and the configuration of a configuration (for example, a polarization layer) that transmits light upon detection.

  The configuration provided in the detection area is not limited to the optical scale 11 that generates polarized light. For example, instead of the optical scale 11, a plate-like member provided with a hole or a transmission part that selectively transmits or transmits light according to the rotation angle of the rotor 10 may be provided. In this case, the change in the rotation angle of the rotor 10 appears as a change in the position and timing at which light is detected by the detection unit. Such a detection unit may not include the polarizing layers PP1 to PP4. By outputting a signal indicating the position where light is detected from the sensor, the angular position of the rotating machine connected to the shaft 12 can be detected.

  Further, the electromagnetic wave as a detection target is not limited to light from a light emitting diode or laser light. The electromagnetic wave as the detection target may be invisible light such as infrared rays or ultraviolet rays, X-rays, or the like. Further, the detection target may be a magnetic force. In this case, the generator generates a magnetic field or a magnetic field by magnetic force. The detection unit performs sensing by detecting a change related to a magnetic force caused by a change in physical quantity (for example, passage of an object) in the detection region. Since the detection target is a magnetic force, a change in the detection area can be detected by a change in the magnetic force. In addition to electromagnetic waves and magnetic forces, the detection target may be sound waves including ultrasonic waves, ions such as plasma, cathode rays (electron beams), and the like. The detection target may be anything that changes due to a change in the physical quantity of the configuration provided in the detection area.

  The change in the physical quantity may be due to the linear motion of the linear motion body existing in the detection area. In this case, the linear motion of the linear motion body can be targeted for sensing by the sensor. The sensor can function as a linear encoder. Specifically, the linear encoder is detected when the detection unit detects a change in the detection target caused by a configuration (for example, a scale or the like) that linearly moves in the detection region relative to the first portion 51 and the second portion 52. The sensor that functions as the sensor performs sensing related to the linear motion of the configuration. Therefore, the presence / absence and the operation position of the linear motion body connected to the encoder according to the present invention can be detected.

  Further, the change in the physical quantity may be due to a change in the concentration or amount of the gas, liquid or solid existing in the detection region. In this case, the sensor functions as a sensor for detecting these concentrations or amounts (for example, a passing amount or a flow rate passing through the detection region). The concentration or amount of the solid is, for example, the concentration or amount per unit space volume of fine objects such as particles, dust, and small pieces that pass through the detection region. In addition, the concentration or amount of the solid may be the amount or concentration of the minute matter contained in the liquid. In this case, an electromagnetic wave such as light is used as a detection target. As described above, according to the present invention, a change in the concentration or amount of gas, liquid, or solid existing in the detection region can be targeted for sensing by the sensor.

(Embodiment 2)
The sensor may be a torque sensor. That is, the torque can be measured according to the present invention. Hereinafter, Embodiment 2 which functions as a torque sensor will be described. FIG. 22 is an exploded perspective view for explaining main components of the torque sensor 101 according to the second embodiment. FIG. 23 is an explanatory diagram illustrating the arrangement of the generating units 41AT and 41BT, the optical scales 11AT and 11BT, and the detecting unit of the torque sensor 101 according to the second embodiment. FIG. 24 is an explanatory diagram schematically illustrating the arrangement of the optical scale and the detection unit of the torque sensor according to the second embodiment. The torque sensor 101 will be described in detail with reference to FIGS.

  In the housing 120, the torque sensor 101 includes a first rotating shaft 110A, a second rotating shaft 110B, a torsion bar 129, an optical scale 11AT, a detection unit 35AT, a light source 41AT, and an optical scale 11BT. It includes a detection unit 35BT and a light source 41BT. The torque sensor 101 is called an axial type torque sensor.

  One end of the torsion bar 129 is attached to the first rotating shaft 110A, and the other end (the end opposite to the end attached to the first rotating shaft 110A) is attached to the second rotating shaft 110B. It is done. That is, the first rotating shaft 110A is provided at one end of the torsion bar 129, and the second rotating shaft 110B is provided at the other end. 110 A of 1st rotating shafts are connected with an input shaft, for example. The second rotating shaft 110B is connected to the output shaft. 110A of 1st rotating shafts and the 2nd rotating shaft 110B are rotatably supported by the housing 120 via the bearing 126A and the bearing 126B.

  In the torque sensor 101, the first rotation shaft 110A may be formed integrally with the input shaft, and the second rotation shaft 110B may be formed integrally with the output shaft. With the above configuration, the input shaft, the first rotating shaft 110A, the torsion bar 129, the second rotating shaft 110B, and the output shaft are arranged coaxially. In the second embodiment, the first rotating shaft 110A and one end of the torsion bar 129 are coupled so as not to rotate, and the other end of the torsion bar 129 and the second rotating shaft 110B are coupled so as not to rotate. . The torsion bar 129 is twisted when torque is input. That is, the torque input via the first rotating shaft 110A causes a rotational displacement between the first rotating shaft 110A and the second rotating shaft 110B, and the torsion bar 129 is twisted.

  The first rotating shaft 110A is a substantially cylindrical member. The first rotary shaft 110A has an optical scale 11AT formed on the outer periphery. In the second embodiment, the optical scale 11AT protrudes from the outer periphery of the first rotating shaft 110A and is arranged in an annular shape in the circumferential direction of the first rotating shaft 110A.

  The second rotating shaft 110B is a substantially cylindrical member. The second rotary shaft 110B has an optical scale 11BT formed on the outer periphery. In the second embodiment, the optical scale 11BT protrudes from the outer periphery of the second rotating shaft 110B and is arranged in an annular shape in the circumferential direction of the second rotating shaft 110B.

  As shown in FIGS. 22-24, on the outer side of the first rotating shaft 110A and the second rotating shaft 110B, in the direction of the rotating shaft Zr of the first rotating shaft 110A and the second rotating shaft 110B, At least two sets of light sources 41AT and 41BT functioning as generation units and sensors 31AT and 31BT functioning as detection units are arranged and provided. In the second embodiment, two sets of light sources 41AT (41BT) and optical sensors 35AT (35BT) are provided as two sets of generation units and detection units, but the number of light sources and optical sensors is not limited thereto. The light sources 41AT and 41BT and the optical sensors 35AT and 35BT form a pair by combining the same light source and the optical sensor, for example, and are arranged in the housing 120.

  Each set of light sources and optical sensors is provided on one substrate. That is, on the substrate 50AT of the sensor 31AT, the first portion 51AT provided with the light source 41AT functioning as a generation unit and the second portion 52AT provided with the optical sensor 35AT functioning as a detection unit are integrated. The substrate 50BT of the sensor 31BT is integrated with a first portion 51BT provided with a light source 41BT that functions as a generation unit and a second portion 52BT provided with an optical sensor 35BT that functions as a detection unit. The optical scale 11AT is located in the detection area between the light source 41AT and the optical sensor 35AT. The optical scale 11BT is located in the detection area between the light source 41BT and the optical sensor 35BT.

  The substrate 50AT has a connection portion 53AT that connects the first portion 51AT and the second portion 52AT. The substrate 50BT has a connection portion 53BT that connects the first portion 51BT and the second portion 52BT. In the substrate 50AT, the connection portion 53AT is located outside the outer periphery of the optical scale 11AT, and the light source 41AT provided in the first portion 51AT and the optical sensor 35AT provided in the second portion 52AT are the detection area in the optical scale 11AT. It is provided in the position which can pinch | interpose. In the substrate 50BT, the connection portion 53BT is located outside the outer periphery of the optical scale 11BT, and the light source 41BT provided in the first portion 51BT and the optical sensor 35BT provided in the second portion 52BT are in the detection region and the optical scale 11BT. It is provided in the position which can pinch | interpose. The connection parts 53AT and 53BT may have wiring connected to the generation part or the detection part as in the first embodiment. In addition, the specific configuration of the substrates 50AT and 50BT may be the same as that of the substrate 50 in the first embodiment. That is, the substrates 50AT and 50BT may be the same as the substrate 50. The first portions 51AT and 51BT may be the same as the first portion 51. The second parts 52AT and 52BT may be the same as the second part 52. Further, the connection parts 53AT and 53BT may be the same as the connection part 53. More specific configurations within a range satisfying the invention-specific matters of the present invention, such as specific shapes of the respective parts of the substrates 50AT and 50BT, may be different from the specific configuration of the substrate 50 in the first embodiment.

  The torque sensor 101 reads the relative displacement (rotational displacement) between the first rotation shaft 110A and the second rotation shaft 110B connected by the torsion bar 129, and reads the optical scale 11AT or the optical scale 11BT. The detection is reflected in the detection change of the sensor 31BT.

  The optical scales 11AT and 11BT are made of, for example, silicon, glass, or a polymer material. The optical scales 11AT and 11BT have a signal track T1 on one or both plate surfaces. As shown in FIGS. 23 and 24, the light source 41AT is disposed at a position facing the optical sensor 35AT via the optical scale 11AT. The light source 41BT is disposed at a position facing the optical sensor 35BT via the optical scale 11BT.

  FIG. 25 is an explanatory diagram for explaining the arrangement of the optical scale and the optical sensor of the torque sensor according to the second embodiment. The optical sensor 35AT shown in FIG. 25 can read the signal track T1 of the optical scale 11AT, and the light source 41AT is disposed at a position facing the optical sensor 35AT via the optical scale 11AT. With this configuration, the light source light 71AT of the light source 41AT passes through the signal track T1 of the optical scale 11AT, and the optical sensor 35AT detects this transmitted light 73AT as incident light. The relationship between the optical sensor 35BT, the optical scale 11BT, and the light source 41BT is the same as the relationship between the optical sensor 35AT, the optical scale 11AT, and the light source 41AT. With this configuration, the light source light 71BT of the light source 41BT passes through the signal track T1 of the optical scale 11BT, and the optical sensor 35BT detects the transmitted light 73BT as incident light.

  When the first rotation shaft 110A rotates, the signal track T1 of the optical scale 11AT moves relative to the optical sensor 35AT. When the second rotation shaft 110B rotates, the signal track T1 of the optical scale 11BT moves relative to the optical sensor 35BT.

  FIG. 26 is a block diagram of the torque detection device according to the second embodiment. The torque detection device 200 includes the above-described torque sensor 101 and the arithmetic device 3A. As shown in FIG. 26, the optical sensor 35AT, the optical sensor 35BT, and the arithmetic device 3A of the torque sensor 101 are connected. Yes. The arithmetic device 3A is connected to a control unit 5A of a rotary machine such as a motor.

  The torque detection device 200 detects transmitted light 73AT and 73BT that are transmitted through and incident on the optical scale 11AT and the optical scale 11BT by the optical sensor 35AT and the optical sensor 35BT. The arithmetic device 3A calculates the relative position between the first rotating shaft 110A of the torque sensor 101 and the sensor 31AT from the detection signal of the optical sensor 35AT. The arithmetic device 3A calculates the relative position between the second rotation shaft 110B of the torque sensor 101 and the sensor 31BT from the detection signal of the optical sensor 35BT.

  The arithmetic device 3A stores the elastic modulus of torsion in the torsion bar 129 in the RAM 4E and the internal storage device 4F. The torque is proportional to the elastic modulus of torsion at the torsion bar 129. Therefore, the calculation device 3A calculates the rotational displacement (deviation amount) between the rotation angle of the first rotation shaft 110A and the rotation angle of the second rotation shaft 110B in order to obtain the twist. The arithmetic device 3A can calculate torque from the elastic coefficient of the torsion bar 129 and information on the relative positions of the first rotating shaft 110A and the second rotating shaft 110B. The arithmetic device 3A outputs the control signal to the control unit 5A such as a rotating machine (motor).

  The arithmetic device 3A is a computer such as a personal computer (PC), and includes an input interface 4A, an output interface 4B, a CPU (Central Processing Unit) 4C, a ROM (Read Only Memory) 4D, and a RAM (Random Access Memory). 4E and an internal storage device 4F. The input interface 4A, output interface 4B, CPU 4C, ROM 4D, RAM 4E and internal storage device 4F are connected by an internal bus. The arithmetic device 3A may be configured with a dedicated processing circuit.

  The input interface 4A receives input signals from the optical sensor 35AT and the optical sensor 35BT of the torque sensor 101, and outputs them to the CPU 4C. The output interface 4B receives a control signal from the CPU 4C and outputs it to the control unit 5A.

  The ROM 4D stores a program such as BIOS (Basic Input Output System). The internal storage device 4F is, for example, an HDD (Hard Disk Drive), a flash memory, or the like, and stores an operating system program and application programs. The CPU 4C implements various functions by executing programs stored in the ROM 4D and the internal storage device 4F while using the RAM 4E as a work area.

  The internal storage device 4F stores, for example, a database that associates the polarization direction of the optical scale 11AT and the optical scale 11BT with the outputs of the optical sensors 35AT and 35BT.

  FIG. 27 is an explanatory diagram illustrating an example of a wire grid pattern of the optical scales 11AT and 11BT according to the second embodiment. The signal track T1 shown in FIG. 27 is the same as the signal track T1 of the optical scale 11 according to the first embodiment. That is, in the optical scales 11AT and 11BT, adjacent metal thin wires g are linearly arranged in parallel as the signal track T1. However, the optical scales 11AT and 11BT according to the second embodiment are different from the optical scale 11 according to the first embodiment in that the optical scales 11AT and 11BT further have holes through which the torsion bars 129 are inserted.

  The generators (light sources 41AT and 41BT) and the detectors (optical sensors 35AT and 35BT) according to the second embodiment have the same configuration as the generator 41 and the detector 35 according to the first embodiment, for example. It is not limited to this. For example, the optical sensors 35AT and 35BT according to the second embodiment may be configured using a part of the detection unit 35 according to the first embodiment. Specifically, for example, in the optical sensors 35AT and 35BT according to the second embodiment, the first light receiving part PD1 having the polarizing layer PP1 and the third light receiving part PD3 having the polarizing layer PP3 in the configuration shown in FIG. 12 are omitted. It may be a configuration. Further, the optical sensors 35AT and 35BT according to the second embodiment have a configuration in which the second light receiving unit PD2 having the polarizing layer PP2 and the fourth light receiving unit PD4 having the polarizing layer PP4 are omitted from the configuration shown in FIG. May be.

  The torque detection device 200 detects torque by using the torsion bar torsion. 110A of 1st rotating shafts and the 2nd rotating shaft 110B are connected by the torsion bar 129 which a twist generate | occur | produces when torque is input. Then, the torque detection device 200 pairs the optical scale 11AT and the optical scale 11BT that are interlocked with each rotation of the first rotating shaft 110A and the second rotating shaft 110B, and the optical scale 11AT and the optical scale 11BT. None, and includes optical sensors 35AT and 35BT that detect the polarization state of the transmitted light that varies depending on the position through which the light source light irradiated to the optical scale 11AT and the optical scale 11BT is transmitted. In the torque detection device 200, the calculation device 3A, which is a calculation means, calculates the relative rotation angle between the optical scale 11AT and the optical sensor 35AT and calculates the relative rotation angle between the optical scale 11BT and the optical sensor 35BT. The rotational displacement of the first rotating shaft 110A and the second rotating shaft 110B is calculated.

  With this configuration, the optical sensor detects the rotation angles of the plurality of optical scales that operate in association with the rotations of the first rotation axis and the second rotation axis in the polarization state in which the transmitted light is polarized and separated. For this reason, compared with the case where the light intensity of the transmitted light is directly detected, the torque detection device can reduce the influence of fluctuations in the detected light amount due to foreign matter or the like even if an optical torque sensor is used. Thereby, since the tolerance | permissible_range of a foreign material becomes wide, a use environment can be expanded. Further, the torque detection device can reduce the influence of fluctuations in the detected light amount due to the accuracy of the optical path (distance from the optical scale to the optical sensor) even when an optical torque sensor is used like the torque sensor according to the second embodiment. Can do. As a result, a degree of freedom can be given to the arrangement of the light source and the optical sensor. Thereby, the torque sensor of a torque detection apparatus can also be reduced in size. Further, the torque detection device can increase the resolution as compared with the magnetic torque sensor.

  In the torque sensor described above, the harness portion is not shown, but at least one part of the first portion 51AT (51BT), the second portion 52AT (52BT), and the connection portion 53AT (53BT) depending on the wiring. You may make it extend from.

  The optical sensors 35AT and 35BT in the torque sensor may have another form. FIG. 28 is an explanatory diagram for describing a modification of the optical sensor according to the second embodiment. FIG. 29 is an explanatory diagram for describing a modification of the optical sensor according to the second embodiment. As shown in FIG. 28, the optical sensor includes a first optical sensor 36A and a second optical sensor 36B. The first optical sensor 36A includes an electrode base portion 36KA, a sensor base portion 36Ka connected to the electrode base portion 36KA, and a first light receiving portion 36a, and can detect the light intensity in the first polarization direction. The first light receiving unit 36a includes a first polarizing layer that separates incident light in the first polarization direction, and receives the first separated light separated by the first polarizing layer.

  The second optical sensor 36B includes an electrode base part 36KB, a sensor base part 36Kb connected to the electrode base part 36KB, and a second light receiving part 36b, and can detect the light intensity in the second polarization direction. The second light receiving unit 36b includes a second polarizing layer that separates the incident light in the second polarization direction, and receives the second separated light separated by the second polarizing layer. And as shown in FIG. 28, the 1st light-receiving part 36a and the 2nd light-receiving part 36b are formed in the comb-tooth shape which mutually meshes | intersects a fixed distance. The electrode base portion 36KA and the electrode base portion 36KB are made of a conductor such as Au, and can energize the first light receiving portion 36a and the second light receiving portion 36b, respectively. More preferably, the first polarization direction and the second polarization direction are relatively different from each other by 90 °. This makes it easier to calculate the polarization angle.

  The optical sensors 35AT and 35BT in the torque sensor may not only have a rectangular outer shape, but may have a shape with an outer diameter along an arc as shown in FIG. For example, when the incident light is circular, the first light receiving unit 36a and the second light receiving unit 36b can receive the same amount of light with respect to the incident light.

  The configuration of the torque sensor provided in the detection region is not limited to the optical scales 11AT and BT that generate polarized light, as in the case of the rotary encoder, and can be changed as appropriate. For example, instead of the optical scales 11AT and BT, a plate-like shape provided with a hole or a transmission part that selectively transmits or transmits light according to the rotation angle of the first rotation shaft 110A and the second rotation shaft 110B. These members may be provided. In this case, the change in the rotation angle appears as a change in the position and timing at which light is detected by the detection unit. Such a detection unit may not have a polarizing layer.

2 Optical encoder 3 Computing device 5 Control unit 10 Rotor 11 Optical scale 12 Shaft 20 Stator 21 Body 22 Chassis 23 Cover 31 Sensor 35 Detection unit 41 Generation unit 50 Substrate 51 First part 52 Second part 53 Connection part 54 Harness part 55a , 55b border

Claims (20)

A generator for generating a predetermined detection target;
A detection unit for detecting the detection target generated by the generation unit across a detection area;
A substrate on which the generation unit and the detection unit are provided,
In the substrate, a first part provided with the generating unit and a second part provided with the detecting unit are integrated. The sensor according to claim 1, wherein the substrate is provided such that the first portion and the second portion are parallel to each other. The sensor according to claim 1, wherein the substrate has a connection portion that connects the first portion and the second portion. The sensor according to claim 3, wherein the connection unit includes a wiring connected to the generation unit or the detection unit. The connecting portion is in a direction perpendicular to the extending direction of the connecting portion between the first portion and the second portion, as compared to the first portion and the second portion, and The sensor according to claim 3 or 4, wherein a width in a direction along the plate surface is small. The sensor according to any one of claims 3 to 5, wherein the substrate is bent at a boundary between the first portion and the connection portion and a boundary between the second portion and the connection portion. One of the first part or the second part is supported hollow by the connection part,
The sensor according to any one of claims 3 to 6, wherein the one is smaller than the other. The sensor according to claim 1, wherein the substrate is bent into a shape in which the generation unit and the detection unit are opposed to each other. The sensor according to any one of claims 1 to 8, wherein the substrate is a flexible substrate. The sensor according to any one of claims 1 to 9, wherein the substrate includes a harness part including a wiring connected to the generation part and the detection part. The sensor according to any one of claims 1 to 10, wherein the detection unit detects a change in the detection target caused by a change in a physical quantity in the detection area. The sensor according to any one of claims 1 to 11, wherein the detection target is an electromagnetic wave. The sensor according to claim 1, wherein the detection target is a magnetic force. The sensor according to claim 1, wherein the change in the physical quantity is due to rotation of a rotating body existing in the detection area. The sensor according to any one of claims 1 to 14, wherein the sensor is a rotary encoder. The sensor according to any one of claims 1 to 13, wherein the change in the physical quantity is due to a linear motion of a linear motion body existing in the detection area. The sensor according to claim 1, wherein the sensor is an encoder. The sensor according to any one of claims 1 to 13, wherein the sensor is a torque sensor. The sensor according to any one of claims 1 to 13, wherein the change in the physical quantity is due to a change in the concentration or amount of a gas, liquid, or solid existing in the detection region. A substrate in which a first part provided with a generation unit for generating a predetermined detection target and a second part provided with a detection unit for detecting the detection target generated by the generation unit across a detection target region are integrated. Forming,
A method for manufacturing a sensor, wherein the generating portion is provided in the first portion of the substrate and the detecting portion is provided in the second portion.

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