JP7284120B2 - Rotation detection system - Google Patents

Description

The present invention relates to a magnetic rotation detection device that uses magnetism to detect rotation of a rotating body, and a rotation detection system that includes an optical rotation detection device that optically detects rotation of a rotating body.

For example, as a device for detecting the rotation of a rotating body such as a motor shaft, there is known a magnetic rotation detector using a magnetic wire that produces a large Barkhausen effect (see Patent Document 1). This rotation detection device includes at least a pair of magnets that form magnetic fields with directions different from each other, and a magnetic sensor that has a coil around a magnetic wire that produces a large Barkhausen effect. A pair of magnets are fixed to, for example, the outer periphery of the rotating body, and move on a circular orbit around the rotation axis of the rotating body as the rotating body rotates. The magnetic sensor is arranged in the vicinity of the circular orbit along which the magnet moves so as not to move with the rotation of the rotating body. When the pair of magnets move on the circular orbit as the rotating body rotates, the pair of magnets alternately pass near the magnetic sensor. As a result, the direction of the magnetic field acting on the magnetic wire of the magnetic sensor changes as the rotating body rotates. A magnetic wire has the property of rapidly reversing its magnetization direction when the direction of the magnetic field acting on it changes, that is, the property of causing the large Barkhausen effect. Therefore, every time the direction of the magnetic field acting on the magnetic wire changes with the rotation of the rotating body, the magnetization direction of the magnetic wire is rapidly reversed, and a pulse signal is output from the coil due to electromagnetic induction. This pulse signal is used to detect the amount of rotation of the rotor (for example, the number of rotations or the angle of rotation).

As another device for detecting rotation of a rotating body, an optical rotation detection device such as an optical encoder is known. An optical rotation detector includes, for example, a light emitting element, a light receiving element, and a disk-shaped code wheel. The codewheel is fixed to the rotating body and rotates with the rotating body. The light-emitting element and the light-receiving element are arranged near the code wheel so as not to rotate together with the rotating body. There are transmissive codewheels and reflective codewheels. A transmissive code wheel has a large number of slits arranged in a portion irradiated with light emitted from a light emitting element during rotation. In the reflective code wheel, a large number of reflective areas and non-reflective areas are alternately arranged in a portion irradiated with light emitted from the light emitting element during rotation. When the code wheel rotates together with the rotating body and light is emitted from the light emitting element to the code wheel, pulsed detection light is formed by the array of slits or the array of reflective and non-reflective areas of the code wheel. Detection light is input to the light receiving element. The amount of rotation (for example, the number of rotations or the angle of rotation) of the rotating body is detected from this pulsed detection light.

Japanese Unexamined Patent Application Publication No. 2019-200101

The magnetic rotation detector has the feature of operating without a power source. Further, the optical rotation detector has the feature that it can detect the rotation angle of the rotating body in detail. By attaching both the magnetic rotation detection device and the optical rotation detection device to a device to be detected such as a motor, the rotation of the rotating body is detected by the magnetic rotation detection device when the power is turned off, and the rotation of the rotating body is detected when the power is turned on. The rotation of the rotating body can be detected with high precision by the magnetic rotation detector and the optical rotation detector.

However, in this case, since the parts constituting the magnetic rotation detecting device and the parts constituting the optical rotation detecting device are attached to the device to be detected, the number of parts to be attached to the device to be detected increases. Therefore, depending on how each part is arranged, the entire device including the magnetic rotation detection device, the optical rotation detection device, and the device to be detected may become large. It may get worse.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, for example, and an object of the present invention is to provide a compact rotation detection device equipped with a magnetic rotation detection device and an optical rotation detection device, and which is easy to assemble parts at the time of manufacture. It is to provide a system.

In order to solve the above problems, the present invention provides a rotation detection system including a magnetic rotation detection device and an optical rotation detection device for detecting rotation of a rotating body, wherein the magnetic rotation detection device detects a direction form magnetic fields different from each other, and have at least a pair of magnetic field forming parts that move on orbits around the rotation axis of the rotating body as the rotating body rotates, and a magnetic wire, the at least pair of magnetic fields A plurality of magnetic field detection units that output magnetic detection signals corresponding to the magnetic fields respectively formed by the formation units, and calculating the amount of rotation of the rotating body based on the magnetic detection signals that are respectively output from the plurality of magnetic field detection units. and a magnetic detection board to which the plurality of magnetic field detection units are fixed, wherein the optical rotation detection device rotates with the rotation of the rotating body, an encoding plate that generates varying detection light; a photodetector that converts the detection light generated by the encoding plate into a photodetection signal that is an electrical signal; and an amount of rotation of the rotating body based on the photodetection signal. and a photodetection substrate which is separated from the magnetic detection substrate and to which the photodetection unit is fixed, wherein the at least one pair of magnetic field generation units and the encoding plate are arranged on the outer circumference of the rotating body. The magnetic detection substrate is fixed to the part, and is provided so as not to move along with the rotation of the rotating body within a magnetic detection area that occupies a part of the outer peripheral area that surrounds the entire outer peripheral side of the rotating body. and the photodetection substrate is provided so as not to move with the rotation of the rotating body in the photodetection region, which occupies a different portion in the circumferential direction from the magnetic detection region in the outer peripheral region. .

According to the present invention, it is possible to provide a compact rotation detection system that includes a magnetic rotation detection device and an optical rotation detection device and that is easy to assemble parts during manufacturing.

It is an explanatory view showing a rotation detection system and a motor of an embodiment of the present invention. FIG. 2 is an explanatory diagram showing a state in which the rotation detection system and the shaft of the motor in FIG. 1 are viewed from above; FIG. 2 is an explanatory diagram showing a cross-section of the shaft of the rotation detection system and the motor cut along the cutting line III-III in FIG. 1, viewed from below in FIG. 1; FIG. 3 is a perspective view showing a magnetic sensor in the magnetic rotation detection device of the rotation detection system according to the embodiment of the present invention; FIG. 4 is an explanatory diagram showing the operation of the magnetic rotation detection device of the rotation detection system according to the embodiment of the present invention; FIG. 2 is an explanatory diagram showing an optical rotation detection device of the rotation detection system according to the embodiment of the present invention; It is explanatory drawing which shows the component arrangement|positioning of the rotation detection system of embodiment of this invention, and its two modifications. FIG. 10 is an explanatory diagram showing two other modifications of the component arrangement of the rotation detection system according to the embodiment of the present invention; FIG. 10 is an explanatory diagram showing still another three modifications of the component arrangement of the rotation detection system according to the embodiment of the present invention; FIG. 5 is an explanatory diagram showing a modification regarding the arrangement of magnets and codewheels in the rotation detection system according to the embodiment of the present invention; FIG. 4 is an explanatory diagram showing a configuration for fixing a substrate in the rotation detection system of the embodiment of the present invention and two modifications thereof; FIG. 5 is an explanatory diagram showing three modifications of the configuration for fixing the yoke pair in the rotation detection system according to the embodiment of the present invention; 1 is a block diagram showing an electrical configuration of a rotation detection system according to an embodiment of the invention; FIG. FIG. 4 is an explanatory diagram showing an electrical connection configuration between parts in the rotation detection system of the embodiment of the present invention and two modifications thereof; FIG. 5 is an explanatory diagram showing another modification of the electrical connection configuration between components in the rotation detection system according to the embodiment of the present invention; FIG. 10 is an explanatory diagram showing three modified examples of the configuration for connecting two magnetic detection boards in the rotation detection system according to the embodiment of the present invention;

(Rotation detection system)
FIG. 1 shows a rotation detection system 1 according to an embodiment of the present invention and a motor 201 as a device to be detected. As shown in FIG. 1, the rotation detection system 1 includes a magnetic rotation detection device 2 having magnets 11 to 14, magnetic sensors 21 to 23, a magnetic detection circuit 37, etc., a code wheel 41, a light detection unit 45, etc. and an optical rotation detection device 3 . The motor 201 has a shaft 202 as a rotating body and a housing 203 as a support. Shaft 202 is rotatably supported by housing 203 . A in FIG. 1 indicates the rotation axis of the shaft 202 . The magnetic rotation detection device 2 and the optical rotation detection device 3 each detect rotation of the shaft 202 . According to the rotation detection system 1, the rotation of the shaft 202 can be detected using the magnetic rotation detection device 2 when the power is turned off, and the magnetic rotation detection device 2 and the optical rotation detection device 3 are used when the power is turned on. Rotation of the shaft 202 can be detected with high accuracy.

Note that in FIG. 1, the motor 201 is arranged so that the tip of the shaft 202 faces upward. Although the arrangement of the motor 201 is not limited, hereinafter, for convenience of explanation, according to the arrangement of the motor 201 shown in FIG. The direction in which the tip is located is defined as upward.

(Magnetic rotation detector)
FIG. 2 shows the rotation detection system 1 and the shaft 202 in FIG. 1 viewed from above. FIG. 3 shows a cross-section of the rotation detection system 1 and the shaft 202 taken along line III--III in FIG. 1, viewed from below.

In the rotation detection system 1, the magnetic rotation detection device 2 includes four magnets 11, 12, 13, 14 (two pairs of magnetic field generators), three magnetic sensors 21, 22, as shown in FIG. , 23 (three magnetic field detection units), three yoke pairs 31 , 32 , 33 (three magnetic field control units), a magnetic detection circuit 37 , and a magnetic detection substrate 39 .

Magnets 11 to 14 are permanent magnets and fixed to the outer circumference of shaft 202 . When the rotation detection system 1 is viewed from above, the magnets 11 to 14 are arranged around the rotation axis A at intervals of 90 degrees. The magnets 11 to 14 move on a track B around the rotation axis A as the shaft 202 rotates.

The magnets 11 and 13 are fixed to the shaft 202 so that their radially outer surfaces are north poles when viewed from above. The magnets 12 and 14 are fixed to the shaft 202 so that their radially outer surfaces are S poles when viewed from above. The magnets 11 to 14 are arranged in the order of magnets 11, 12, 13, and 14 in the counterclockwise direction when viewed from above, for example, so that the polarities of adjacent magnets are opposite in the circumferential direction of the shaft 202. there is

As shown in FIG. 1, each of the magnets 11 to 14 is elongated in the vertical direction, the upper end of each magnet 11 to 14 is located above the magnetic detection board 39, and the lower end of each magnet 11 to 14 is located above the magnetic detection board 39. It is positioned below the magnetic detection board 39 . As a result, the magnetic sensor 21 arranged on the upper surface 39A (front surface) of the magnetic detection substrate 39 and the two magnetic sensors 22 and 23 arranged on the lower surface 39B (rear surface) of the magnetic detection substrate 39 are both 14 faces the moving area. Note that the polarities of the magnetic poles on the radially outer surface of the magnet 11 when viewed from above are the same from the upper end portion to the lower end portion of the magnet 11, and are all north poles. The magnet 13 is also the same. In addition, the polarities of the magnetic poles on the radially outer surface of the magnet 12 when viewed from above are the same from the upper end portion to the lower end portion of the magnet 12, and are all S poles. The magnet 14 is also the same.

The magnetic sensors 21-23 are sensors that detect the magnetic fields formed by the magnets 11-14, respectively, using the large Barkhausen effect. Each of the magnetic sensors 21-23 outputs magnetic detection signals corresponding to the magnetic fields formed by the magnets 11-14, respectively. As shown in FIG. 2, the magnetic sensor 21 is arranged on the upper surface 39A of the magnetic detection board 39, and as shown in FIG.

FIG. 4 shows the magnetic sensor 21. FIG. As shown in FIG. 4 , the magnetic sensor 21 has a magnetic wire 25 , a coil 26 and a bobbin 27 . The magnetic wire 25 is a large Barkhausen element. Specifically, the magnetic wire 25 is a linear ferromagnetic material that produces a large Barkhausen effect and has uniaxial anisotropy. The magnetic wire 25 is called a composite magnetic wire. The magnetic wire 25 can be formed, for example, by twisting a semi-hard magnetic wire containing iron and cobalt. The magnetic wire 25 is arranged inside the shaft of a bobbin 27 made of a non-magnetic material such as resin. The coil 26 is provided on the outer peripheral side of the magnetic wire 25 . For example, the coil 26 is formed by winding an enameled wire around the outer peripheral side of the shaft portion of the bobbin 27 in which the magnetic wire 25 is arranged. Magnetic sensor 22 and magnetic sensor 23 also have the same configuration as magnetic sensor 21 .

Also, the length of the magnetic wire 25 is, for example, approximately 10 mm to 20 mm. In each of the magnetic sensors 21 to 23, a magnetic wire 25 is arranged in a linearly elongated state inside a bobbin 27. As shown in FIG. Depending on the length of the magnetic wire 25, the length of each magnetic sensor 21-23 is, for example, approximately 10 mm-20 mm.

When the rotation detection system 1 is viewed from above, the area surrounding the entire outer circumference of the shaft 202, that is, the outer circumference area of the shaft 202, is divided into a magnetic detection area R1 and a light detection area R2. For example, as shown in FIG. 2, when the rotation detection system 1 is viewed from above, the magnetic detection region R1 is generally on the right side of the outer peripheral region of the shaft 202, and the light detection region R2 is generally on the left side. A magnetic detection substrate 39 is provided in the magnetic detection region R1. The magnetic detection substrate 39 is generally formed in a sector shape. The magnetic detection substrate 39 is arranged such that a plane including the upper surface 39A of the magnetic detection substrate 39 and a plane including the lower surface 39B of the magnetic detection substrate 39 are orthogonal to the rotation axis A. Also, the magnetic detection board 39 is separated from the shaft 202 , the magnets 11 - 14 and the code wheel 41 . Further, as shown in FIG. 1, the magnetic detection board 39 is fixed to the housing 203 of the motor 201 via the holder 52 so as not to move as the shaft 202 rotates. The magnetic sensor 21 is fixed to the upper surface 39A of the magnetic detection board 39 as shown in FIG. 2, and the magnetic sensors 22 and 23 are fixed to the lower surface 39B of the magnetic detection board 39 as shown in FIG.

Each of the magnetic sensors 21 to 23 is arranged so that the plane including the axis of the magnetic wire 25 is orthogonal to the rotation axis A. As shown in FIG. Note that the axis of the magnetic wire 25 is a straight line passing through the center of the cross section of the magnetic wire 25 in the extending direction of the magnetic wire 25 .

As shown in FIGS. 2 and 3, when the rotation detection system 1 is viewed from above, each of the magnetic sensors 21 to 23 is centered on the rotation axis A at the central portion of the axis of the magnetic wire 25 in its extending direction. It is arranged so as to be in contact with the circumference of a circle C with . Further, when viewing the rotation detection system 1 from above, the magnetic sensors 21 to 23 are arranged on the outer peripheral side of the track B along which the magnets 11 to 14 move. Moreover, the magnetic sensors 21 to 23 are arranged at different positions in the rotation direction of the shaft 202 . Specifically, when the rotation detection system 1 is viewed from above, the magnetic sensors 21 to 23 are arranged around the shaft 202 at intervals of 60 degrees.

Further, when the rotation detection system 1 is viewed from above, two magnetic sensors adjacent to each other in the rotation direction of the shaft 202 among the magnetic sensors 21 to 23 partially overlap each other. Specifically, when the rotation detection system 1 is viewed from above, the magnetic sensors 21 to 23 are arranged such that the magnetic sensor 22 is positioned adjacent to one of the magnetic sensors 21 and the magnetic sensor 22 is positioned adjacent to the other magnetic sensor 21 . They are arranged side by side around the rotation axis A so that 23 is positioned. One end of the magnetic sensor 21 and one end of the magnetic sensor 22 overlap each other, and the other end of the magnetic sensor 21 and one end of the magnetic sensor 23 overlap each other. When the rotation detection system 1 is viewed from the direction of the rotation axis A (upward or downward), the phrase “one portion and another portion “overlap” means that the one portion and the other portion “overlap”. and are opposed to each other with the magnetic detection substrate 39 interposed therebetween in the direction of the rotation axis A (direction parallel to the rotation axis A).

The yoke pairs 31-33 have the function of controlling the directions of the magnetic fields formed by the magnets 11-14. Each yoke pair 31 - 33 has a pair of yoke pieces 35 . Each yoke piece 35 is made of a soft magnetic material such as pure iron, silicon steel, pearlomae, or amorphous metal in a plate shape. The yoke pair 31 is arranged on the upper surface 39A of the magnetic detection substrate 39, and the yoke pair 32 and the yoke pair 33 are arranged on the lower surface 39B of the magnetic detection substrate 39. As shown in FIG.

The yoke pair 31, as shown in FIG. 2, is arranged between the magnetic sensor 21 and the track B along which the magnets 11-14 move. Specifically, one yoke piece 35 of the yoke pair 31 is arranged between one end of the magnetic sensor 21 and the track B, and the other yoke piece 35 is arranged between the other end of the magnetic sensor 21 and the track B. is placed between. Also, these two yoke pieces 35 are separated from each other. Each yoke piece 35 of the yoke pair 31 rises from the upper surface 39A of the magnetic detection substrate 39 in a direction orthogonal to the upper surface 39A (upward).

The yoke pair 32 is arranged between the magnetic sensor 22 and the track B, as shown in FIG. Specifically, one yoke piece 35 of the yoke pair 32 is arranged between one end of the magnetic sensor 22 and the track B, and the other yoke piece 35 is arranged between the other end of the magnetic sensor 22 and the track B. is placed between. Also, these two yoke pieces 35 are separated from each other. Each yoke piece 35 of the yoke pair 32 rises from the lower surface 39B of the magnetic detection substrate 39 in a direction perpendicular to the lower surface 36B (downward).

The yoke pair 33 is arranged between the magnetic sensor 23 and the track B along which the magnets 11-14 move. The positional relationship between the pair of yoke pieces 35 of the yoke pair 33 and the magnetic sensor 23 is the same as the positional relationship between the pair of yoke pieces 35 of the yoke pair 32 and the magnetic sensor 22, as shown in FIG.

Further, when the rotation detection system 1 is viewed from above, two yoke pairs adjacent to each other in the rotational direction of the shaft 202 among the yoke pairs 31 to 33 partially overlap each other. Specifically, one yoke piece 35 of the yoke pair 31 partially overlaps one yoke piece 35 of the yoke pair 32 . The other yoke piece 35 of the yoke pair 31 partially overlaps the one yoke piece 35 of the yoke pair 33 .

The magnetic detection circuit 37 is a circuit that calculates the amount of rotation of the shaft 202 based on the magnetic detection signals output from the magnetic sensors 21-23. The magnetic detection circuit 37 is provided on the lower surface 39B of the magnetic detection substrate 39. As shown in FIG. Specifically, the magnetic detection circuit 37 is formed, for example, as an integrated circuit integrated into one chip. Fixed.

FIG. 5 shows the operation of the magnetic rotation detector 2. As shown in FIG. FIG. 5 depicts six states of the magnetic rotation detector 2 viewed from above. That is, in FIG. 5, the shaft 202 rotates clockwise, and the upper left magnetic rotation detection device 2 in FIG. The adjacent magnetic rotation detection device 2 shows the state when the rotation angle of the shaft 202 reaches 30°, and the magnetic rotation detection device 2 on the right side shows the state when the rotation angle of the shaft 202 reaches 60°. indicates the state of the moment. Further, the magnetic rotation detector 2 on the lower left in FIG. 5 shows the state when the rotation angle of the shaft 202 reaches 90 degrees. has reached 120°, and the magnetic rotation detection device 2 on the right side thereof shows the state when the rotation angle of the shaft 202 has reached 150°. 5, W1 indicates the waveform of the magnetic detection signal output from the magnetic sensor 21, W2 indicates the waveform of the magnetic detection signal output from the magnetic sensor 22, and W3 indicates the magnetic field output from the magnetic sensor 23. The waveform of the detection signal is shown.

When the direction of the external magnetic field acting on the magnetic wire 25 changes and the strength of the external magnetic field reaches a certain threshold value, the magnetic wire 25 of each of the magnetic sensors 21 to 23 has a large Barkhausen effect. It has the property of instantaneously reversing the magnetization direction. When the magnetization direction of the magnetic wire 25 is reversed instantaneously, a sharp pulse is output from the coil 26 provided on the outer peripheral side of the magnetic wire 25 by electromagnetic induction. Specifically, when the external magnetic field acting on the magnetic wire 25 changes from one direction to the other direction and the strength of the external magnetic field reaches a certain threshold value, the magnetization direction of the magnetic wire 25 changes from one direction to the other direction. , and the coil 26 outputs, for example, a positive pulse. Further, when the external magnetic field acting on the magnetic wire 25 changes from another direction to one direction and the intensity of the external magnetic field reaches a certain threshold value, the magnetization direction of the magnetic wire 25 instantly changes from the other direction to one direction. After changing, the coil 26 outputs, for example, a negative pulse.

In the magnetic rotation detector 2, the magnets 11-14 move on the track B as the shaft 202 rotates, so that the magnetic fields acting on the magnetic wires 25 of the magnetic sensors 21-23 change. For example, while shaft 202 is rotating clockwise in FIG. 5, magnets 11 and 14 approach magnetic sensor 21 when the rotation angle of shaft 202 reaches 0 degrees. At this time, the magnetic wire 25 of the magnetic sensor 21 has a A downward magnetic field acts. As a result, the magnetization direction of the magnetic wire 25 of the magnetic sensor 21 is reversed, and the magnetic sensor 21 outputs, for example, a positive pulse P1. In addition, the magnetic field is controlled by the yoke pair 31 so that the lines of magnetic force directed from the magnet 11 to the magnet 14 pass downward through the magnetic wire 25 of the magnetic sensor 21, so that the level of the pulse P1 can be increased.

Next, when the rotation angle of shaft 202 reaches 30 degrees, magnets 11 and 12 approach magnetic sensor 22 . At this time, magnetic fields formed by the magnets 11 and 12 act on the magnetic wire 25 of the magnetic sensor 22 in a diagonally upper left direction in FIG. As a result, the magnetization direction of the magnetic wire 25 of the magnetic sensor 22 is reversed, and the magnetic sensor 22 outputs, for example, a negative pulse P2. In addition, the magnetic field is controlled by the yoke pair 32 so that the magnetic line of force directed from the magnet 11 to the magnet 12 passes through the magnetic wire 25 of the magnetic sensor 22 in an obliquely upper left direction, whereby the level of the pulse P2 can be increased. .

Next, when the rotation angle of shaft 202 reaches 60 degrees, magnets 11 and 14 approach magnetic sensor 23 . At this time, the magnetic fields formed by the magnets 11 and 14 act on the magnetic wire 25 of the magnetic sensor 23 in a diagonally lower left direction in FIG. As a result, the magnetization direction of the magnetic wire 25 of the magnetic sensor 23 is reversed, and the magnetic sensor 23 outputs, for example, a positive pulse P3. In addition, the magnetic field is controlled by the yoke pair 33 so that the magnetic line of force directed from the magnet 11 to the magnet 14 passes through the magnetic wire 25 of the magnetic sensor 23 obliquely downward to the left, thereby increasing the level of the pulse P3. .

Next, when the rotation angle of shaft 202 reaches 90 degrees, magnets 11 and 12 approach magnetic sensor 21 . At this time, magnetic fields formed by the magnets 11 and 12 act on the magnetic wire 25 of the magnetic sensor 21 in the upward direction in FIG. As a result, the magnetization direction of the magnetic wire 25 of the magnetic sensor 21 is reversed, and the magnetic sensor 21 outputs, for example, a negative pulse P4. Also, the level of the pulse P4 can be increased by controlling the magnetic field by the yoke pair 31. FIG.

Next, when the rotation angle of shaft 202 reaches 120 degrees, magnets 12 and 13 approach magnetic sensor 22 . At this time, the magnetic fields formed by the magnets 12 and 13 act on the magnetic wire 25 of the magnetic sensor 22 in a diagonally downward right direction in FIG. As a result, the magnetization direction of the magnetic wire 25 of the magnetic sensor 22 is reversed, and the magnetic sensor 22 outputs, for example, a positive pulse P5. Also, the level of the pulse P5 can be increased by controlling the magnetic field by the yoke pair 32. FIG.

Next, when the rotation angle of shaft 202 reaches 150 degrees, magnets 11 and 12 approach magnetic sensor 23 . At this time, magnetic fields formed by the magnets 11 and 12 act on the magnetic wire 25 of the magnetic sensor 23 in a diagonally upward right direction in FIG. As a result, the magnetization direction of the magnetic wire 25 of the magnetic sensor 23 is reversed, and the magnetic sensor 23 outputs, for example, a negative pulse P6. Also, the level of the pulse P6 can be increased by controlling the magnetic field by the yoke pair 33. FIG.

A magnetic detection signal including pulses P1 and P4 output from the magnetic sensor 21, a magnetic detection signal including pulses P2 and P5 output from the magnetic sensor 22, and a magnetic detection signal including pulses P3 and P6 output from the magnetic sensor 23. The signal is output to magnetic detection circuit 37 . The magnetic detection circuit 37 calculates the amount of rotation of the shaft 202 based on the magnetic detection signals output from the magnetic sensors 21-23. As a method for calculating the amount of rotation of the shaft 202, for example, the method described in International Publication No. 2016/002437 can be used. Further, the magnetic detection circuit 37 outputs a first rotation amount signal indicating the amount of rotation of the shaft 202 calculated based on the magnetic detection signals output from the magnetic sensors 21 to 23 to the arithmetic processing circuit 51, which will be described later. do.

(Optical rotation detector)
FIG. 6 schematically shows the optical rotation detection device 3. As shown in FIG. In the rotation detection system 1, the optical rotation detection device 3 includes a code wheel 41 (encoding plate), a photodetection unit 45, and a photodetection substrate 49, as shown in FIG.

The code wheel 41 is a member that generates detection light that changes according to the rotation of the shaft 202 . As shown in FIG. 6, the code wheel 41 is made of a non-magnetic material such as resin and has a disc shape. An insertion hole 42 for attaching the codewheel 41 to the shaft 202 is provided at the center of the codewheel 41 . A shaft 202 is inserted into the insertion hole 42 . The code wheel 41 is fixed to the outer circumference of the shaft 202 and rotates as the shaft 202 rotates, as shown in FIG.

Further, the code wheel 41 is arranged below the portion of the shaft 202 to which the magnets 11 to 14 are fixed. Also, the code wheel 41 is adjacent to the magnets 11-14. Also, the upper surface 41A (front surface) of the code wheel 41 faces the lower surface 49B of the photodetection substrate 49 .

Further, as shown in FIG. 6, the upper surface 41A of the code wheel 41 is provided with a plurality of reflecting portions 43 and a plurality of non-reflecting portions 44. As shown in FIG. The reflective portions 43 and the non-reflective portions 44 are alternately arranged so as to form a circle around the center Q (rotational axis A) of the code wheel 41 .

The light detection unit 45 is a unit in which a light emitting element 46, a light receiving element 47 (light detection section) and a light detection circuit 48 are integrated as shown in FIG. The light emitting element 46 is, for example, a light emitting diode. The light receiving element 47 is, for example, a phototransistor. Photodetector circuit 48 is an integrated circuit.

As shown in FIGS. 2 and 3, when the rotation detection system 1 is viewed from above, the outer peripheral area of the shaft 202 is divided into a magnetic detection area R1 and a light detection area R2. A detection board 49 is provided. The photodetection substrate 49 is generally formed in a sector shape. Further, the photodetection substrate 49 is a substrate different from the magnetic detection substrate 39, and the photodetection substrate 49 and the magnetic detection substrate 39 are separated from each other. The photodetector substrate 49 is arranged such that a plane including the upper surface 49A of the photodetector substrate 49 and a plane including the lower surface 49B of the photodetector substrate 49 are orthogonal to the rotation axis A. Also, the photodetector board 49 is separated from the shaft 202 , the magnets 11 - 14 and the codewheel 41 . Further, as shown in FIG. 1, the photodetector board 49 is fixed to the housing 203 of the motor 201 via the holder 52 so as not to move as the shaft 202 rotates. The photodetector unit 45 is fixed to the lower surface 49B of the photodetector substrate 49 as shown in FIG. Further, as shown in FIG. 6, the light detection unit 45 is arranged such that the light emitting element 46 and the light receiving element 47 face the arrangement of the reflecting portions 43 and the non-reflecting portions 44 on the code wheel 41 .

In FIG. 6, while the shaft 202 is rotating, the irradiation light L1 emitted from the light emitting element 46 is irradiated onto the arrangement of the reflecting portions 43 and the non-reflecting portions 44 . As a result, pulsed detection light L2 is generated, the amount of which changes according to the rotation of shaft 202 . The generated detection light L2 is input to the light receiving element 47 . The light receiving element 47 converts the detection light L2 into a photodetection signal, which is an electrical signal, and outputs the photodetection signal to the photodetection circuit 48 . The photodetection circuit 48 calculates the amount of rotation of the shaft 202 based on the photodetection signal. As a method of calculating the rotation amount of the shaft 202 based on this light detection signal, a well-known method of detecting the number of rotations or rotation angle of the shaft of the motor using an optical encoder can be used. The photodetection circuit 48 also outputs a second rotation amount signal indicating the rotation amount of the shaft 202 calculated based on the photodetection signal to the arithmetic processing circuit 51 described later.

(other components of the rotation detection system)
As shown in FIG. 1, the rotation detection system 1 includes, in addition to the magnetic rotation detection device 2 and the optical rotation detection device 3, an arithmetic processing circuit 51, internal connectors 83 to 86, external connectors 91 to 93, a connection cable 87, 95 and holder 52 are provided.

The arithmetic processing circuit 51 calculates the final rotation amount of the shaft 202 based on the first rotation amount signal output from the magnetic detection circuit 37 and the second rotation amount signal output from the light detection circuit 48, It is a circuit that outputs a third rotation amount signal indicating the calculated final rotation amount to the outside. For example, the arithmetic processing circuit 51 corrects the rotation amount of the shaft 202 indicated by the first rotation amount signal using the rotation amount of the shaft 202 indicated by the second rotation amount signal, thereby increasing the rotation amount of the shaft 202. Generating and outputting a third rotation amount signal that accurately indicates. The arithmetic processing circuit 51 is formed, for example, as an integrated circuit integrated into one chip, and the chip of the arithmetic processing circuit 51 is attached to the lower surface 49B of the photodetection substrate 49, as shown in FIG.

The internal connectors 83 to 86 and the connection cable 87 are means for electrically connecting the magnetic detection circuit 37 and the arithmetic processing circuit 51 . External connectors 91 to 93 and connection cable 95 are means for electrically connecting arithmetic processing circuit 51 and motor control circuit 205 provided outside rotation detection system 1 . A motor control circuit 205 is a circuit that controls the motor 201 based on the third rotation amount signal output from the arithmetic processing circuit 51 . The electrical connection between the magnetic detection circuit 37 and the arithmetic processing circuit 51 and the electrical connection between the arithmetic processing circuit 51 and the motor control circuit 205 will be described in detail later.

As described above, in the rotation detection system 1 of the present embodiment, the magnetic detection board 39 provided with the magnetic sensors 21 to 23, the yoke pairs 31 to 33, and the magnetic detection circuit 37 is part of the outer peripheral region of the shaft 202. A photodetection substrate 49 provided with a photodetection unit 45 is provided in a photodetection region R2 that occupies a portion different in the circumferential direction from the magnetism detection region R1 in the outer peripheral region of the shaft 202. It is According to this configuration, the magnetic sensors 21 to 23, the yoke pairs 31 to 33, and the magnetic detection circuit 37, which constitute a part of the magnetic rotation detection device 2, and the light detection circuit, which constitutes a part of the optical rotation detection device 3, are provided. The units 45 can be distributed and arranged at different positions on the outer peripheral side of the shaft 202 . Therefore, compared to the case where the magnetic sensors 21 to 23, the yoke pairs 31 to 33, the magnetic detection circuit 37, and the light detection unit 45 are stacked vertically (in the direction of the rotation axis A), the rotation detection system 1 can be reduced in the vertical direction, and the size of the rotation detection system 1 can be reduced.

Further, according to the present embodiment, since the magnetic detection board 39 and the light detection board 49 are separated from each other, in manufacturing the rotation detection system 1, it is possible to improve the assembly efficiency of the parts. Specifically, the magnetic sensors 21 to 23, the yoke pairs 31 to 33, and the magnetic detection circuit 37, which constitute a part of the magnetic rotation detection device 2, are mounted on the magnetic detection board 39, and the optical rotation detection device 3 is mounted. The magnetic detection board on which the magnetic sensors 21 to 23, the yoke pairs 31 to 33, and the magnetic detection circuit 37 are mounted after mounting the light detection unit 45 constituting a part of the light detection board 49 on the light detection board 49 in separate processes. 39 and the photodetection board 49 on which the photodetection unit 45 is mounted are assembled to the outer peripheral side of the shaft 202 of the motor 201 to assemble the rotation detection system 1 . Since the magnetic rotation detection device 2 and the optical rotation detection device 3 have different principles of rotation detection, the magnetic rotation detection device 2 and the optical rotation detection device 3 may be developed or manufactured by different manufacturers. . According to the present embodiment, when manufacturing the rotation detection system 1, for example, the first manufacturer manufactures the magnetic detection board 39 on which the magnetic sensors 21 to 23, the yoke pairs 31 to 33, and the magnetic detection circuit 37 are mounted. A second manufacturer manufactures the photodetection board 49 on which the photodetection unit 45 is mounted, and the magnetic detection board 39 and the photodetection board 49 are assembled to the motor 201 by or a third manufacturer can be easily adopted, and the rotation detection system 1 can be manufactured efficiently.

Further, in this embodiment, the magnetic sensors 21 to 23 are separately arranged on the upper surface 39A and the lower surface 39B of the magnetic detection substrate 39. As shown in FIG. Therefore, the magnetic sensors 21 to 23 are arranged so that the plane including the axis of the magnetic wire 25 is orthogonal to the rotation axis A, and when the rotation detection system 1 is viewed from above, the magnetic sensors 21 to 23 are adjacent to each other. By arranging the magnetic sensors 21 to 23 so that the magnetic sensors overlap each other, the magnetic sensors 21 to 23 can be concentrated in a small area while maintaining the accuracy of rotation detection by the magnetic sensors 21 to 23 . That is, by arranging the magnetic sensors 21 to 23 so that the plane including the axis of the magnetic wire 25 is perpendicular to the rotation axis A, the vertical dimension of the area occupied by the magnetic sensors 21 to 23 can be reduced. Even when the magnetic sensors 21 to 23 are arranged in this way, by arranging the magnetic sensors 21 to 23 separately on the upper surface 39A and the lower surface 39B of the magnetic detection substrate 39, two magnetic sensors adjacent to each other in the circumferential direction of the shaft 202 can be arranged. The two magnetic sensors can be separated in the circumferential direction to the extent that the accuracy of rotation detection can be maintained. Furthermore, by arranging the magnetic sensors 21 to 23 so that two adjacent magnetic sensors in the magnetic sensors 21 to 23 overlap each other when the rotation detection system 1 is viewed from above, the rotation detection accuracy is maintained while the magnetic field is detected. The size of the area occupied by the sensors 21 to 23 in the left-right direction or the front-rear direction can be reduced. As a result, the size of the rotation detection system can be reduced.

Also, in this embodiment, the code wheel 41 is adjacent to the magnets 11 to 14 in the vertical direction. By bringing the code wheel 41 and the magnets 11 to 14 close to each other in the vertical direction in this manner, the vertical dimension of the rotation detection system 1 can be reduced.

Further, according to the present embodiment, a large Barkhausen element is used as the magnetic wire 25 of each of the magnetic sensors 21 to 23, which facilitates a non-powered magnetic rotation detection device with high detection accuracy of the rotation of the shaft 202. can be realized.

(Modified example of parts arrangement)
In the rotation detection system 1 described above, as shown in FIG. 7A, the magnetic sensor 21 and the yoke pair 31 are arranged on the upper surface 39A of the magnetic detection substrate 39, and the two magnetic sensors 22 and 23 and the two yoke pairs 32 are arranged. , 33 and the magnetic detection circuit 37 are arranged on the lower surface 39B of the magnetic detection substrate 39. As shown in FIG. Also, the photodetection circuit 48 and the arithmetic processing circuit 51 are arranged on the lower surface 49B of the photodetection substrate 49 . Also, the code wheel 41 is arranged below the magnets 11-14. However, in the rotation detection system 1, the arrangement of these parts is not limited to the arrangement shown in FIG. 7(A). Several modifications will be described below regarding the arrangement of these parts.

First, the arrangement of components shown in FIG. 7A may be changed as follows. That is, the magnetic sensor 21 and the yoke pair 31 may be arranged on the lower surface 39B of the magnetic detection substrate 39, and the two magnetic sensors 22, 23 and the two yoke pairs 32, 33 may be arranged on the upper surface 39A of the magnetic detection substrate 39. . In FIG. 7A, the magnetic detection circuit 37 may be arranged on the upper surface 39A of the magnetic detection substrate 39, regardless of the arrangement of the magnetic sensors 21-23 and the yoke pairs 31-33. 39B.

Further, as shown in FIG. 7(B), two magnetic detection substrates 39 are provided in the magnetic detection region R1, and these magnetic detection substrates 39 are arranged at different positions in the vertical direction, and the magnetic sensor 21 and the yoke pair are arranged. 31 may be placed on the lower surface 39B of the upper magnetic detection substrate 39 and the two magnetic sensors 22, 23 and the two yoke pairs 32, 33 may be placed on the upper surface 39A of the lower magnetic detection substrate 39. Also, the arrangement of components shown in FIG. 7B may be changed as follows. That is, the magnetic sensor 21 and the yoke pair 31 are arranged on the upper surface 39A of the lower magnetic detection substrate 39, and the two magnetic sensors 22, 23 and the two yoke pairs 32, 33 are arranged on the lower surface 39B of the upper magnetic detection substrate 39. may be placed. In FIG. 7B, the magnetic detection circuit 37 may be arranged on the upper surface 39A of the lower magnetic detection substrate 39 regardless of the arrangement of the magnetic sensors 21 to 23 and the yoke pairs 31 to 33. and may be arranged on the lower surface 39B of the magnetic detection substrate 39 on the upper side.

Further, as shown in FIG. 7(C), two magnetic detection substrates 39 are provided in the magnetic detection region R1, and these magnetic detection substrates 39 are arranged at different positions in the vertical direction, and the magnetic sensor 21 and the yoke pair are arranged. 31 may be placed on the lower surface 39B of the upper magnetic detection substrate 39, and the two magnetic sensors 22, 23 and the two yoke pairs 32, 33 may be placed on the lower surface 39B of the lower magnetic detection substrate 39. Also, the arrangement of the parts shown in FIG. 7C may be changed as follows. That is, the magnetic sensor 21 and the yoke pair 31 are arranged on the lower surface 39B of the lower magnetic detection substrate 39, and the two magnetic sensors 22, 23 and the two yoke pairs 32, 33 are arranged on the lower surface 39B of the upper magnetic detection substrate 39. may be placed. In FIG. 7C, the magnetic detection circuit 37 may be arranged on the lower surface 39B of the lower magnetic detection substrate 39 regardless of the arrangement of the magnetic sensors 21 to 23 and the yoke pairs 31 to 33. and may be arranged on the lower surface 39B of the magnetic detection substrate 39 on the upper side.

Alternatively, the photodetection unit 45 and the arithmetic processing circuit 51 may be arranged on the upper surface 49A of the photodetection substrate 49, as shown in FIG. 8A. Alternatively, the photodetector unit 45 may be arranged on the upper surface 49A of the photodetector substrate 49, the arithmetic processing circuit 51 may be arranged on the lower surface 49B of the photodetector substrate 49, and the photodetector unit 45 may be arranged on the photodetector substrate 49B. 49 may be arranged on the lower surface 49B, and the arithmetic processing circuit 51 may be arranged on the upper surface 49A of the photodetector substrate 49. FIG. Further, when the photodetection unit 45 is arranged on the upper surface 49A of the photodetection board 49, the light emitting element 46 and the light receiving element 47 provided in the photodetection unit 45 and the reflecting portion 43 and the non-reflecting portion provided in the code wheel 41 are arranged. The code wheel 41 is arranged above the magnets 11 to 14 so that the array of the portions 44 and the array of the portions 44 face each other, and the surface of the code wheel 41 on which the reflecting portion 43 and the non-reflecting portion 44 are provided faces downward. .

Further, as shown in FIG. 8B, the photodetection substrate 49 is arranged below the magnetic detection substrate 39, and the photodetection unit 45 and the arithmetic processing circuit 51 are arranged on the upper surface 49A of the photodetection substrate 49. good too. When the position of the photodetection substrate 49 is lowered in this way, the position of the code wheel 41 must be lowered in order to appropriately set the distance between the light emitting element 46 and the light receiving element 47 and the code wheel 41. There is In that case, the code wheel 41 may be fixed to the outer circumference of the magnets 11-14.

Further, as shown in FIG. 9A or 9B, instead of the photodetection substrate 49, a photodetection substrate 61 is provided so as to extend over the magnetic detection region R1 and the photodetection region R2, and the photodetection unit 45 and Arithmetic processing circuit 51 is arranged in a portion of photodetection substrate 61 located within photodetection region R2, and magnetic detection substrate 39 provided with magnetic sensors 21 to 23, yoke pairs 31 to 33 and magnetic detection circuit 37 is used as a magnetic sensor. It may be arranged above or below the photodetection substrate 61 in the detection region R1. In this case, the light detection substrate 61 is formed, for example, in the shape of a disk, and an insertion hole 62 is formed in the center thereof for passing the shaft 202 to which the magnets 11 to 14 are fixed.

Further, as shown in FIG. 9C, a photodetection substrate 61 is provided so as to extend over the magnetic detection region R1 and the photodetection region R2. A unit 45 and an arithmetic processing circuit 51 are arranged, a hole 63 (or notch) is formed in a portion of the photodetection substrate 61 located within the magnetic detection region R1, and magnetic sensors 21 to 23, yoke pairs 31 to 33 and The magnetic detection substrate 39 provided with the magnetic detection circuit 37 is arranged above (or below) the photodetection substrate 61 in the magnetic detection region R1, and a part of the member provided on the magnetic detection substrate 39 (for example, a magnetic The sensor 21 and yoke pair 31 ) may be inserted into holes 63 (or notches) formed in the photodetector substrate 61 . In addition, in this modification, the hole 63 is connected to the insertion hole 62 (the hole 63 and the insertion hole 62 are continuously formed). According to this modification, in the configuration in which the photodetection substrate 61 is provided over the magnetic detection region R1 and the photodetection region R2, the vertical distance between the magnetic detection substrate 39 and the photodetection substrate 61 can be reduced. , the vertical dimension of the rotation detection system 1 can be reduced.

In addition, in the modification shown in FIG. 8B, FIG. 9A, or FIG. 9B, the code wheel 41 is fixed to the outer peripheral portions of the magnets 11-14. Alternatively, as shown in FIG. 10, each of the magnets 11 to 14 is divided into two magnet pieces 65, and the two magnet pieces 65 of each of the magnets 11 to 14 are spaced apart in the vertical direction. The codewheel 41 may be placed between two magnet pieces 65 of 14 and fixed to the outer circumference of the shaft 202 .

(Modified example of substrate fixation)
In the rotation detection system 1 described above, as shown in FIG. A photodetection board 49 provided with a processing circuit 51 is fixed to a housing 203 of the motor 201 via a holder 52 . The holder 52 is made of, for example, a resin material or a metal material.

In the rotation detection system 1 including two magnetic detection substrates 39 as in the modification shown in FIG. 7(B) or FIG. 7(C), as shown in FIG. The substrate 39 can be fixed to the housing 203 of the motor 201 via the holder 52 , and the other magnetic detection substrate 39 can be fixed to the one magnetic detection substrate 39 via the support member 67 .

9A, 9B, or 9C, a rotation detection system in which the photodetection substrate 61 is provided over the magnetic detection region R1 and the photodetection region R2. 1, as shown in FIG. 11C, the photodetection board 61 is fixed to the housing 203 of the motor 201 via the holder 52, and the magnetic detection board 39 is attached to the photodetection board via the supporting member 68. 61 may be fixed.

(Modified example of fixation of yoke pair)
In the rotation detection system 1 described above, the yoke pairs 31 to 33 are fixed to the magnetic detection board 39 as shown in FIG. 11(A). However, in the rotation detection system 1, the method of fixing the yoke pairs 31-33 is not limited to this.

For example, the yoke pairs 31 to 33 may be directly fixed to the holder 52 as shown in FIG. 12(A). Specifically, the holder 52 is made of a non-magnetic material such as resin, and the yoke pair fixing portion 71 is formed in a part of the holder 52 . The yoke pair fixing portion 71 is formed so as to be positioned between the magnetic sensors 21-23 and the track B of the magnets 11-14. Then, the yoke pairs 31 to 33 are embedded inside the yoke pair fixing portion 71 . According to this modification, each yoke pair 31-33 can be firmly fixed. Also, by providing the yoke pairs 31 to 33 in a portion other than the magnetic detection board 39, the number of components to be mounted on the magnetic detection board 39 can be reduced.

Also, as shown in FIG. 12B, each yoke pair 31 to 33 may be fixed to the magnetic sensor. For example, the bobbin 27 of each of the magnetic sensors 21 to 23 is integrally formed with a yoke piece support portion 72 for supporting the yoke pair, and the yoke piece support portion 72 is fixed to the yoke piece support portion 72 . According to this modification, since the yoke pairs corresponding to each of the magnetic sensors 21 to 23 are fixed, the positional relationship between the magnetic sensors 21 to 23 and the corresponding yoke pairs (for example, the distance between them) is can be determined accurately.

Also, as shown in FIG. 12C, the magnetic sensors 21 to 23 and the yoke pairs 31 to 33 may be surrounded by, for example, a resin material to integrate them. Specifically, a molding 73 is formed by integrating the magnetic sensors 21 to 23 and the yoke pairs 31 to 33 by resin molding. According to this modification, by attaching the molding 73 to the magnetic detection board 39, the magnetic sensors 21 to 23 and the yoke pairs 31 to 33 can be provided on the magnetic detection board 39 all at once. Assembly work can be simplified.

(Electrical connection configuration and its modification)
FIG. 13 shows the electrical configuration of the rotation detection system 1, and FIG. 14(A) shows the electrical connection configuration between parts for embodying the electrical configuration of the rotation detection system 1. As shown in FIG.

As shown in FIG. 13, in the rotation detection system 1 described above, the magnetic sensors 21 to 23 each output a magnetic detection signal to the magnetic detection circuit 37, and the magnetic detection circuit 37 outputs the first rotation amount signal to the arithmetic processing circuit 51. Output to On the other hand, the light receiving element 47 outputs a photodetection signal to the photodetection circuit 48 , and the photodetection circuit 48 outputs a second rotation amount signal to the arithmetic processing circuit 51 . Further, arithmetic processing circuit 51 outputs a third rotation amount signal to motor control circuit 205 .

In order to realize such input/output of signals, as shown in FIG. It is connected to the magnetic detection circuit 37 via a conductive portion 81 such as a through hole. The magnetic detection circuit 37 is connected to an internal connector 83 via a conductive pattern provided on the magnetic detection board 39 and a conductive portion 82 such as a through hole. The internal connector 83 is a connector for connecting the magnetic detection circuit 37 provided on the magnetic detection board 39 and the arithmetic processing circuit 51 provided on the light detection board 49 , and is provided on the magnetic detection board 39 . .

Also, the internal connector 83 is connected to an internal connector 86 via an internal connector 84 , a connection cable 87 and an internal connector 85 . The internal connector 86 is a connector for connecting the magnetic detection circuit 37 provided on the magnetic detection board 39 and the arithmetic processing circuit 51 provided on the photodetection board 49 , and is provided on the photodetection board 49 . . An internal connector 84 is connected to one end of the connection cable 87 , and an internal connector 85 is connected to the other end of the connection cable 87 . The internal connector 84 is detachably connected to the internal connector 83 , and the internal connector 85 is detachably connected to the internal connector 86 .

Also, the internal connector 86 is connected to the arithmetic processing circuit 51 via a conductive portion 88 such as a conductive pattern provided on the photodetector board 49 . Also, the light receiving element 47 is connected to the photodetection circuit 48 via a circuit provided inside the photodetection unit 45 . The photodetection circuit 48 is also connected to the arithmetic processing circuit 51 via a conductive portion 89 such as a conductive pattern provided on the photodetection substrate 49 . Further, the arithmetic processing circuit 51 is connected to an external connector 91 via a conductive portion 90 such as a conductive pattern provided on the photodetector board 49 . The external connector 91 is a connector for connecting the rotation detection system 1 and the motor control circuit 205 .

Also, the external connector 91 is connected to the motor control circuit 205 via an external connector 92, a connection cable 95, an external connector 93, another connector 94, and the like. An external connector 92 is connected to one end of the connection cable 95 , and an external connector 93 is connected to the other end of the connection cable 95 . The external connector 92 is detachably connected to the external connector 91 , and the external connector 93 is detachably connected to another connector 94 . Another connector 94 is connected to the motor control circuit 205 .

As described above, in the rotation detection system 1, the magnetic detection circuit 37 provided on the magnetic detection board 39 and the arithmetic processing circuit 51 provided on the light detection board 49 are connected to the conductive portions 82 and 88 and the internal connectors 83 to 86. and a connection cable 87 for connection. With this configuration, the first rotation amount signal indicating the rotation amount of the shaft 202 detected by the magnetic rotation detection device 2 and the second rotation amount signal indicating the rotation amount of the shaft 202 detected by the optical rotation detection device 3 are generated. An electric circuit for supplying both the quantity signal and the quantity signal to the arithmetic processing circuit 51 can be easily formed. Specifically, at the time of manufacturing the rotation detection system 1, for example, the magnetic detection board 39 provided with the magnetic sensors 21 to 23, the yoke pairs 31 to 33, and the magnetic detection circuit 37, the light detection unit 45, and the arithmetic processing circuit 51 is attached to the housing 203 of the motor 201, the internal connector 84 is connected to the internal connector 83, and the internal connector 85 is connected to the internal connector 86. An electric circuit for supplying the quantity signal to the arithmetic processing circuit 51 can be easily formed. Further, since the rotation detection system 1 and the motor control circuit 205 can be connected using a bundle of connection cables 95, the rotation detection system 1 can be easily assembled to the motor 201. FIG. The conductive portions 82 and 88, the internal connectors 83 to 86, and the connection cable 87 are specific examples of a first internal connection path, the conductive portion 89 is a specific example of a second internal connection path, and the conductive portion 90, The external connectors 91-93 and the connection cable 95 are specific examples of the first external connection path.

However, the electrical connection configuration in the rotation detection system 1 is not limited to this. For example, an electrical connection configuration as shown in FIG. 14(B) may be employed. That is, an external connector 102 is provided on the magnetic detection board 39 , and the magnetic detection circuit 37 and the external connector 102 are connected via conductive patterns and conductive portions 101 such as through holes provided on the magnetic detection board 39 . An external connector 108 is provided on the photodetection board 49 , and the photodetection circuit 48 and the external connector 108 are connected via a conductive portion 107 such as a conductive pattern provided on the photodetection board 49 . Then, the external connector 102 is connected to the motor control circuit 205 via the external connector 103, the connection cable 106, the external connector 104, another connector 105, etc., and the external connector 108 is connected to the external connector 109, the connection cable 112, the external It connects to the motor control circuit 205 via the connector 110 and another connector 111 or the like. An arithmetic processing circuit 51 calculates the final rotation amount of the shaft 202 based on the first rotation amount signal output from the magnetic detection circuit 37 and the second rotation amount signal output from the photodetection circuit 48. is provided outside the rotation detection system 1 (for example, inside the motor control circuit 205). Moreover, an internal connector and a connection cable for connecting the magnetic detection board 39 and the light detection board 49 are not provided. According to this electrical connection configuration, when the arithmetic processing circuit 51 is provided outside the rotation detection system 1, the first rotation amount signal and the second rotation amount signal are sent to the arithmetic processing circuit 51. An electric circuit for supplying can be easily formed. Conductive portion 101, external connectors 102 to 104, and connection cable 106 are specific examples of a second external connection path, and conductive portion 107, external connectors 108 to 110, and connection cable 112 are specific examples of a third external connection path. For example.

Also, as an electrical connection configuration in the rotation detection system 1, a configuration as shown in FIG. 14(C) can be adopted. That is, the arithmetic processing circuit 51 is provided on the photodetection board 49 . An output path connecting the output terminal of the arithmetic processing circuit 51 and the motor control circuit 205 and an external connector are provided using the conductive portion 121, the external connectors 122, 123 and 124, the connection cables 125 and 126, the conductive portion 127, and the like. 124 and the input terminal of the arithmetic processing circuit 51 are formed. Also, using the conductive portion 128 , internal connectors 129 and 130 and connection cable 131 , the output terminal of the magnetic detection circuit 37 is connected to the input path through the external connector 124 . In such an electrical connection configuration, the first rotation amount signal output from the magnetic detection circuit 37 is transmitted through the conductive portion 128, the internal connectors 129 and 130, the connection cable 131, the external connector 124 and the input path (connection cable 126, It is input to the arithmetic processing circuit 51 via the external connector 123, the external connector 122, and the conductive portion 127). Also, the third rotation amount signal output from the arithmetic processing circuit 51 is input to the motor control circuit 205 via the output path (the conductive portion 121, the external connectors 122 to 124, the connection cable 125, etc.). The conductive portions 127, 128, the external connectors 122 to 124, the internal connectors 129, 130, and the connection cables 126, 131 are specific examples of the first internal connection paths. Cable 125 is a specific example of a first external connection path.

Further, in the electrical connection configuration of the rotation detection system 1 shown in FIG. , 88, internal connectors 83 to 86, and a connection cable 87. Alternatively, both ends of the connection cable 87 are soldered to the conductive portion 82 and the conductive portion 88, respectively, to form a magnetic detection circuit. 37 and the arithmetic processing circuit 51 may be connected. A connection member such as a press fit may be used to connect the connection cable 87 and the conductive portion 82 or 88 . In this case, for example, a press fit is crimped on the end of the connection cable 87, a through hole is formed in the photodetector board 49 as a part of the conductive portion 88, and the press fit is inserted into the through hole. and the conductive portion 88 are connected. A board direct insertion type connector may be used to connect the magnetic detection circuit 37 provided on the magnetic detection board 39 and the arithmetic processing circuit 51 provided on the light detection board 49 . In this case, for example, a board direct insertion type connector is provided on the photodetection board 49 , the conductive part 88 is connected to the connector, and the conductive part 82 is extended to the edge of the magnetic detection board 39 . Then, the magnetic detection circuit 37 and the arithmetic processing circuit 51 are connected by inserting the edge of the magnetic detection board 39 into a board direct insertion type connector.

Moreover, in the electrical connection configuration of the rotation detection system 1 shown in FIG. 14A, the connection cable 95 may be directly connected to the conductive portion 90 by soldering or the like without using the external connectors 91 and 92 . Moreover, in the electrical connection configuration of the rotation detection system 1 shown in FIG. 14B, the connection cable 106 may be directly connected to the conductive portion 101 by soldering or the like without using the external connectors 102 and 103 . Moreover, in the electrical connection configuration of the rotation detection system 1 shown in FIG. 14B, the connection cable 112 may be directly connected to the conductive portion 107 by soldering or the like without using the external connectors 108 and 109 . Also, in the electrical connection configuration of the rotation detection system 1 shown in FIG. good too. Moreover, in the electrical connection configuration of the rotation detection system 1 shown in FIG. 14C, the connection cable 131 may be directly connected to the conductive portion 128 by soldering or the like without using the internal connectors 129 and 130 .

As shown in FIG. 7B or 7C, in the rotation detection system 1 having two magnetic detection substrates 39, the magnetic sensor provided on one of the magnetic detection substrates 39 and the magnetic sensor on the other Electrical connection with the magnetic detection circuit 37 provided on the magnetic detection board 39 can be made as follows. For example, as shown in FIG. 15, the upper magnetic detection board 39 is provided with an internal connector 142, the magnetic sensor 21 and the internal connector 142 are connected, and the conductive part 141 such as a conductive pattern provided on the upper magnetic detection board 39 is connected. connect through An internal connector 145 is provided on the lower magnetic detection board 39, and the internal connector 145 and the magnetic detection circuit 37 are connected via a conductive part 147 such as a conductive pattern provided on the lower magnetic detection board 39. . Furthermore, internal connectors 142 and 145 are connected via internal connectors 143 and 144 and connection cable 146 . Thereby, the magnetic sensor 21 provided on the upper magnetic detection board 39 and the magnetic detection circuit 37 provided on the lower magnetic detection board 39 can be electrically connected. Incidentally, the conductive portions 141 and 147, the internal connectors 142 to 145 and the connection cable 146 are specific examples of the third internal connection path.

In the rotation detection system 1 having two magnetic detection substrates 39, the magnetic sensor provided on one magnetic detection substrate 39 and the magnetic detection circuit 37 provided on the other magnetic detection substrate 39 are electrically connected. The connection configuration (third internal connection path) is as follows. For example, as shown in FIG. 16A, two magnetic detection boards 39 are provided with internal connectors 148 and 149, respectively. The magnetic sensor 21 provided on the lower side may be electrically connected to the magnetic detection circuit 37 provided on the lower magnetic detection substrate 39 .

Further, as shown in FIG. 16B, a conductive terminal 151 is provided between the two magnetic detection substrates 39, and each end of the conductive terminal 151 is connected to the conductive portion provided on the two magnetic detection substrates 39. The magnetic sensor 21 provided on the upper magnetic detection board 39 and the magnetic detection circuit 37 provided on the lower magnetic detection board 39 are electrically connected by soldering to 141 and 147 respectively. may

Alternatively, as shown in FIG. 16C, the conductive portions 141 and 147 provided on the two magnetic detection substrates 39 may be connected to each other via springs 153 made of a conductive material. Also, the conductive portions 141 and 147 provided on the two magnetic detection substrates 39 may be connected by soldering a cable, or may be connected by using a cable and press fit.

In the above embodiment, the magnetic sensors 21 to 23 are arranged separately on the upper surface 39A and the lower surface 39B of the magnetic detection substrate 39, and the magnetic sensors 21 to 23 are adjacent to each other when the rotation detection system 1 is viewed from above. Two magnetic sensors are superimposed on each other. However, in the magnetic sensors 21 to 23, when the rotation detection system 1 is viewed from above, two adjacent magnetic sensors are not arranged so as to overlap each other, and two adjacent magnetic sensors are arranged on the same surface of the magnetic detection substrate 39. They may be placed so close together that they are difficult to place on top of each other. Arranging two magnetic sensors so close to each other that it is difficult to arrange them on the same surface of the magnetic detection board 39 means, for example, that two magnetic sensors are mounted on the board. The necessary parts and areas (areas for soldering each magnetic sensor to the substrate, etc.) are arranged so as to be close enough to interfere with each other, and the area required for wiring to each magnetic sensor is reduced. For example, they may be placed so close that they interfere with each other.

In the above embodiment, the magnetic rotation detection device 2 having two pairs of magnets 11 to 14 and three magnetic sensors 21 to 23 was taken as an example, but the number of magnets and the number of magnetic sensors are limited to this. not. The number of magnets in the magnetic rotation detector of the present invention may be one pair, or three or more pairs. Also, the number of magnetic sensors may be two, or four or more. Further, the interval between the magnets 11-14 is not limited to 90 degrees, and the interval between the magnetic sensors 21-23 is not limited to 60 degrees.

In the above embodiment, the magnetic detection region R1 is wider than the light detection region R2 in the outer peripheral region of the shaft 202, but the ratio of the magnetic detection region R1 and the light detection region R2 in the outer peripheral region of the shaft 202 The ratio of each is not limited.

Further, in the above-described embodiment, the optical rotation detector 3 employs the reflective code wheel 41 having the reflecting portion 43 and the non-reflecting portion 44, but a transmissive code wheel having slits may also be employed. . In this case, the light emitting element 46 and the light receiving element 47 are arranged so as to face each other with the code wheel interposed therebetween.

In addition, the present invention can be modified as appropriate within the scope not contrary to the gist or idea of the invention that can be read from the claims and the entire specification, and the rotation detection system involving such modifications is also the technical concept of the present invention. include.

1 rotation detection system 2 magnetic rotation detection device 3 optical rotation detection device 11 to 14 magnet (magnetic field forming part)
21 to 23 magnetic sensor (magnetic field detection part)
25 magnetic wire 31-33 yoke pair (magnetic field control part)
37 magnetic detection circuit 39 magnetic detection substrate 41 code wheel (encode plate)
45 light detection unit 46 light emitting element 47 light receiving element (light detection section)
48 photodetector circuit 49, 61 photodetector substrate 51 arithmetic processing circuit 71 yoke pair fixing portion 72 yoke piece support portion 82, 88, 127, 128 conductive portion (first internal connection path)
83-86, 129, 130 internal connector (first internal connection path)
87, 126, 131 connection cable (first internal connection path)
89 conductive part (second internal connection path)
90, 121 conductive portion (first external connection path)
91, 92, 93 external connector (first external connection path)
95 connection cable (first external connection path)
101 conductive portion (second external connection path)
102, 103, 104 external connectors (second external connection paths)
106 connection cable (second external connection path)
107 conductive portion (third external connection path)
108, 109, 110 external connector (third external connection path)
112 connection cable (third external connection path)
122 to 124 external connectors (first external connection path, first internal connection path)
125 connection cable (first external connection path)
141, 147 conductive portion (third internal connection path)
142 to 145, 148, 149 internal connector (third internal connection path)
146 connection cable (third internal connection path)
151 conductive terminal (third internal connection path)
153 spring (third internal connection path)
201 motor 202 shaft (rotating body)
203 housing (support)
R1 magnetic detection area R2 light detection area

Claims (13)

A rotation detection system comprising a magnetic rotation detection device and an optical rotation detection device for detecting rotation of a rotating body,
The magnetic rotation detection device is
at least a pair of magnetic field generators that respectively generate magnetic fields with directions different from each other and move on orbits around the rotation axis of the rotor as the rotor rotates;
a plurality of magnetic field detection units each having a magnetic wire and outputting a magnetic detection signal corresponding to the magnetic field generated by each of the at least one pair of magnetic field generation units;
a magnetic detection circuit that calculates the amount of rotation of the rotating body based on the magnetic detection signals output from the plurality of magnetic field detection units;
A magnetic detection board to which the plurality of magnetic field detection units are fixed,
The optical rotation detection device is
an encoding plate that rotates with the rotation of the rotating body and generates detection light that changes according to the rotation of the rotating body;
a photodetector that converts the detection light generated by the encoding plate into a photodetection signal that is an electrical signal;
a photodetection circuit that calculates the amount of rotation of the rotating body based on the photodetection signal;
A photodetection substrate that is separated from the magnetic detection substrate and to which the photodetection unit is fixed,
the at least one pair of magnetic field generators and the encoding plate are fixed to the outer periphery of the rotating body;
The magnetic detection substrate is provided so as not to move along with the rotation of the rotor within a magnetic detection area that occupies part of an outer peripheral area that surrounds the entire circumference of the outer circumference of the rotor,
The rotation detection device, wherein the photodetection substrate is provided in a photodetection region that occupies a different portion in the circumferential direction from the magnetic detection region in the outer peripheral region so as not to move along with the rotation of the rotating body. system. The photodetection substrate is provided over the magnetic detection region and the photodetection region,
The photodetection unit is fixed to a portion of the photodetection substrate located within the photodetection region,
2. The rotation detection system according to claim 1, wherein the magnetic detection board is arranged on one side or the other side of the photodetection board in the rotation axis direction of the rotor. 3. The plurality of magnetic field detectors according to claim 1, wherein the plurality of magnetic field detectors are arranged separately on one surface and the other surface in the rotation axis direction of the rotating body on the magnetic detection substrate. rotation detection system. 3. The magnetic field detectors according to claim 1, wherein the plurality of magnetic field detectors are arranged separately on two magnetic detection substrates arranged at different positions in the rotation axis direction of the rotating body. Rotation detection system. 5. The encode plate is adjacent to the at least one pair of magnetic field generators on one side or the other side of the at least one pair of magnetic field generators in the rotation axis direction. A rotation detection system as described in . 5. The rotation detecting system according to claim 1, wherein said encoding plate is fixed to the outer periphery of said at least one pair of magnetic field forming portions. A plurality of magnetic field control units for controlling the direction of the magnetic field formed by each magnetic field forming unit,
The plurality of magnetic field control units are arranged between the plurality of magnetic field detection units and the track,
7. The rotation detection system according to any one of claims 1 to 6, wherein each of said magnetic field control units is fixed to said magnetic detection board. A plurality of magnetic field control units for controlling the direction of the magnetic field formed by each magnetic field forming unit,
The plurality of magnetic field control units are arranged between the plurality of magnetic field detection units and the track,
7. The rotation detection system according to any one of claims 1 to 6, wherein each of said magnetic field control units is fixed to a support that rotatably supports said rotating body without interposing said magnetic detection substrate. . A plurality of magnetic field control units for controlling the direction of the magnetic field formed by each magnetic field forming unit,
The plurality of magnetic field control units are arranged between the plurality of magnetic field detection units and the track,
7. The rotation detection system according to claim 1, wherein each magnetic field control section is fixed to the magnetic field detection section. Equipped with an arithmetic processing circuit,
The magnetic detection circuit outputs a first rotation amount signal indicating the amount of rotation of the rotating body calculated based on the magnetic detection signal,
The photodetection circuit outputs a second rotation amount signal indicating the rotation amount of the rotating body calculated based on the photodetection signal,
The arithmetic processing circuit calculates a final rotation amount of the rotating body based on the first rotation amount signal and the second rotation amount signal, and outputs a third rotation amount indicating the calculated final rotation amount. output a rotation amount signal,
The magnetic detection circuit is provided on the magnetic detection substrate,
The photodetection circuit and the arithmetic processing circuit are provided on the photodetection substrate,
The magnetic detection board and the light detection board are provided with a first internal connection path for electrically connecting the magnetic detection circuit and the arithmetic processing circuit,
The photodetection substrate has a second internal connection path for electrically connecting the photodetection circuit and the arithmetic processing circuit, and an electrical connection between the arithmetic processing circuit and a circuit external to the rotation detection system. A first external connection path is provided for connecting to
The first rotation amount signal output from the magnetic detection circuit is input to the arithmetic processing circuit through the first internal connection path, and the second rotation amount signal output from the photodetection circuit is The third rotation amount signal input to the arithmetic processing circuit via the second internal connection path and output from the arithmetic processing circuit is input to the external circuit via the first external connection path. 10. A rotation detection system according to any one of claims 1 to 9, characterized in that: The magnetic detection circuit outputs a first rotation amount signal indicating the amount of rotation of the rotating body calculated based on the magnetic detection signal,
The photodetection circuit outputs a second rotation amount signal indicating the rotation amount of the rotating body calculated based on the photodetection signal,
The magnetic detection circuit is provided on the magnetic detection substrate,
The photodetection circuit is provided on the photodetection substrate,
The magnetic detection board is provided with a second external connection path for electrically connecting the magnetic detection circuit and a circuit outside the rotation detection system,
The photodetection substrate is provided with a third external connection path for electrically connecting the photodetection circuit and the external circuit,
The first rotation amount signal output from the magnetic detection circuit is input to the external circuit via the second external connection path, and the second rotation amount signal output from the photodetection circuit is 10. The rotation detection system according to any one of claims 1 to 9, wherein the signal is input to said external circuit via said third external connection path. The magnetic detection circuit is provided on one of the two magnetic detection substrates,
The two magnetic detection substrates are provided with a third magnetic detection circuit for electrically connecting the magnetic field detection section arranged on the other magnetic detection substrate of the two magnetic detection substrates and the magnetic detection circuit. An internal connection path is provided respectively,
5. The magnetic detection circuit according to claim 4, wherein the magnetic detection signal output from the magnetic field detection section arranged on the other magnetic detection substrate is input to the magnetic detection circuit via the third internal connection path. A rotation detection system as described. 13. The rotation detection system according to any one of claims 1 to 12, wherein the magnetic wire is a large Barkhausen element.

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