JP2021001908A - Encoder device, drive device, stage device, and robot device - Google Patents

Abstract

To decrease a frequency of maintenance.SOLUTION: An encoder device comprises a position detector for detecting positional information of a moving part. The encoder device comprises a signal generator for generating a detection signal according to changes in a magnetic field accompanying movement of the moving part. The encoder device comprises a power supply part for supplying power to the position detector, in a state that power supply from a first power source is cut off. The encoder device comprises a cutoff part for cutting off the power supply from the power supply part to the position detector, on the basis of a trigger signal indicating completion of work of the position detector.SELECTED DRAWING: Figure 1

Description

The present invention relates to an encoder device, a drive device, a stage device, and a robot device.

A multi-rotation type encoder device that distinguishes the number of rotations of a rotating shaft is mounted on various devices such as a robot device (see, for example, Patent Document 1 below). During operation of the robot device, the encoder device receives power from, for example, the main power supply of the robot device, and rotates position information including multi-rotation information indicating the number of rotations and angular position information indicating an angular position of less than one rotation. Is detected.

When the robot device finishes a predetermined process, its main power may be turned off. In this case, the power supply from the main power supply of the robot device to the encoder device is also stopped. The robot device may need information such as the initial posture the next time the main power is switched on (eg, when the next operation is started). Therefore, the encoder device is required to hold the multi-rotation information even when power is not supplied from the outside. Therefore, as an encoder device, a device that holds multi-rotation information by the electric power supplied from the battery is used in a state where the electric power supply from the main power source cannot be obtained.

Japanese Unexamined Patent Publication No. 8-50034

Encoder devices are required to reduce the frequency of maintenance.

In the first aspect of the present invention, an encoder device is provided. The encoder device includes a position detection unit that detects the position information of the moving unit. The encoder device includes a signal generation unit in which a detection signal is generated by a change in a magnetic field accompanying the movement of the moving unit. The encoder device includes a power supply unit that supplies power to the position detection unit in a state where the power supply from the first power supply is cut off. The encoder device includes a cutoff unit that cuts off the supply of electric power from the power supply unit to the position detection unit based on a trigger signal indicating the end of the operation of the position detection unit.

It is a figure which shows the encoder device which concerns on embodiment. It is a figure which shows the signal generation part and the sensor which concerns on embodiment. It is a figure which shows the circuit structure of the encoder device which concerns on embodiment. It is a figure which shows the blocking part and its operation which concerns on embodiment. It is a figure which shows the blocking part and its operation which concerns on embodiment. It is a figure which shows the blocking part and its operation which concerns on embodiment. It is a figure which shows the operation of the encoder device which concerns on embodiment. It is a figure which shows the example of the detection signal, enable signal, delay signal, and discharge control signal which concerns on embodiment. It is a figure which shows the modification of the blocking part which concerns on embodiment. It is a figure which shows the drive device which concerns on embodiment. It is a figure which shows the stage apparatus which concerns on embodiment. It is a figure which shows the robot apparatus which concerns on embodiment.

FIG. 1 is a diagram showing an encoder device EC according to the present embodiment. This encoder device EC detects the position information (moving position information) of the moving unit. The encoder device EC is, for example, a rotary encoder, the moving unit is, for example, the rotation axis SF of the motor M (power supply unit), and the movement of the moving unit is, for example, rotation around a predetermined axis. Further, the position information of the moving portion is, for example, the rotation position information of the rotation axis SF.

The rotary shaft SF is, for example, a shaft (rotor) of the motor M, and is an action shaft (output shaft) connected to the shaft of the motor M via a power transmission unit such as a transmission and connected to a load. You may. The rotation position information detected by the encoder device EC is supplied to the motor control unit MC. The motor control unit MC controls the rotation of the motor M by using the rotation position information supplied from the encoder device EC. The motor control unit MC controls the rotation of the rotation shaft SF. The encoder device EC may be, for example, a linear encoder, or may detect position information (moving position information) of a moving unit of a power driving unit such as a linear motor or a flat motor.

The encoder device EC includes a position detection unit (position detection system) 1, a power supply unit 2, a signal generation unit 5, and a cutoff unit 6. The signal generation unit 5 intermittently (intermittently) generates an electric signal (detection signal) as the rotation axis SF rotates. The power supply unit 2 starts supplying the power consumed by the position detection unit 1 (power used) in response to the generation of the detection signal in the signal generation unit 5. The position detection unit 1 detects the rotation position information of the rotation axis SF at all times or in response to the generation of the detection signal. The position detection unit 1 intermittently detects the rotation position information of the rotation axis SF by generating the detection signal intermittently. For example, the power supply unit 2 receives the detection signal and starts supplying power to the position detection unit 1, and the position detection unit 1 receives the power supply from the power supply unit 2 and receives the power supply from the power supply unit 2 to obtain the rotation position information of the rotating shaft SF. Start detection. The cutoff unit 6 receives a trigger signal indicating the end of the operation (series of operations, detection operation) of the position detection unit 1 and cuts off the power supply from the power supply unit 2 to the position detection unit 1.

Hereinafter, each part of the encoder device EC will be described. The position detection unit 1 detects the rotation position information of the rotation axis SF. The encoder device EC in the present embodiment is a multi-rotation absolute encoder, and includes multi-rotation information indicating the number of rotations of the rotation axis SF and angular position information indicating an angular position (rotation angle) of less than one rotation. Is detected. The encoder device EC includes a multi-rotation information detection unit 3 that detects the multi-rotation information of the rotation axis SF, and an angle detection unit 4 that detects the angle position of the rotation axis SF.

At least a part of the position detection unit 1 (eg, the angle detection unit 4) detects the rotation position information of the rotation axis SF by the electric power supplied from the first power source 7 in a normal state, for example. The first power source 7 is, for example, the main power source of a device (eg, drive device, stage device, robot device) on which the encoder device EC is mounted, and supplies electric power consumed for driving the rotary shaft SF. For example, the motor control unit MC controls the rotation of the rotating shaft SF by adjusting the electric power from the first power source 7 and supplying the electric power to the motor M based on the detection result of the encoder device EC. The position detection unit 1 operates by receiving power from the first power source 7 in a state where the first power source 7 is turned on (a state in which the first power source 7 is turned on, a normal state). Further, the angle detection unit 4 (or its circuit) can operate while the first power supply 7 is turned on to the position detection unit 1. For example, when the first power supply 7 is turned on to the position detection unit 1 and becomes a normal state, the angle detection unit 4 starts detecting the angle position information (eg, calculation), and similarly, the multi-rotation information detection unit 3 Also starts the detection of multi-rotation information (eg, calculation).

Further, at least a part of the position detection unit 1 (eg, the multi-rotation information detection unit 3) is in a state where the power supply from the first power supply 7 is cut off (eg, the power supply from the first power supply is stopped). A second power source (eg, power supply unit 2) different from the first power source 7 in the state of being turned on, the state where the first power source 7 is not turned on, the state where the first power source 7 is turned off, and the backup state). , It operates by the electric power supplied from the battery 33) of the electric power supply unit 2. For example, in a state where the power supply from the first power source 7 is cut off to the position detection unit 1, the power supply unit 2 supplies at least a part of the position detection unit 1 (eg, the multi-rotation information detection unit 3). On the other hand, electric power is intermittently (intermittently, selectively) supplied based on the detection signal, and at least a part of the position detection unit 1 (eg, the multi-rotation information detection unit 3) is intermittently operated. The position detection unit 1 detects at least a part (eg, multi-rotation information) of the rotation position information of the rotation axis SF when power is supplied from the power supply unit 2. Further, the multi-rotation information detection unit 3 (or its circuit) can operate when the first power supply 7 is not turned on. For example, when the first power supply 7 is not turned on and the power is supplied from the second power supply to the backup state, the multi-rotation information detection unit 3 continues to detect the multi-rotation information, but the angle detection unit 4 Stops the detection of angular position information. As described above, the multi-rotation information detection 3 is based on the detection signal and is based on the multi-rotation information regardless of the on / off state (normal state and backup state) of the power supply (first power supply 7, second power supply such as battery 33, etc.). Perform detection.

The multi-rotation information detection unit 3 is, for example, a magnetic detection unit, and detects multi-rotation information by magnetism. The multi-rotation information detection unit 3 includes, for example, a magnet 11, a magnetic sensor 12, a processing unit 13, and a storage unit 14. The magnet 11 is provided on a disk (first rotating body, first moving body) 15 fixed to the rotating shaft SF. Since the disk 15 rotates together with the rotation axis SF, the magnet 11 rotates (moves) in conjunction with the rotation axis SF. The magnet 11 is fixed to the outside of the rotating shaft SF, and the relative positions of the magnet 11 and the magnetic sensor 12 change with each other due to the rotation of the rotating shaft SF. The strength and direction of the magnetic field on the magnetic sensor 12 formed by the magnet 11 changes with the rotation of the rotation axis SF. The magnetic sensor 12 detects the magnetic field formed by the magnet 11, and the processing unit 13 detects the magnetic field formed by the magnet by the magnetic sensor 12, and based on the result, the position information of the rotation axis SF (eg, multi-rotation information). Is detected (calculated). The storage unit 14 stores the position information detected and processed by the processing unit 13 based on the storage instruction (data writing command) of the position information (eg, multi-rotation information) from the processing unit 13. The magnet 11 may be movable as long as it can move relative to the magnetic sensor 12 or the signal generating unit 5, and the magnetic sensor 12 may be provided on the disk 15 instead of the magnet 11. Further, for example, the processing unit 13 is a multi-rotation processing unit that processes multi-rotation information.

The angle detection unit 4 is an optical or magnetic encoder, and obtains position information (angle position information, absolute or relative position information) within one rotation of the scale (second rotating body, second moving body) S. To detect. For example, in the case of an optical encoder, the angle detection unit 4 detects the angle position information within one rotation of the rotation axis SF by reading the patterning information of the scale S with the light receiving element. The patterning information of the scale S is, for example, a light / dark pattern due to a slit (transmission pattern) or a reflection pattern on the scale S. The angle detection unit 4 detects the angle position information of the same rotation axis SF as the detection target of the multi-rotation information detection unit 3. The angle detection unit 4 includes a light emitting element 21, a scale S, a light receiving sensor 22, and a processing unit 23. For example, the processing unit 23 is an angular position processing unit that processes position information within one rotation of the scale S.

The scale S is fixedly provided on the rotation axis SF. The scale S includes an incremental pattern INC and an absolute pattern ABS. The scale S may be provided on the disk 15 or may be a member integrated with the disk 15. In this case, for example, one or both of the incremental pattern INC and the absolute pattern ABS may be provided on the same side surface or the opposite side surface of the magnet 11 on the disk 15. Further, one or both of the incremental pattern INC and the absolute pattern ABS may be provided on at least one of the inside and the outside with respect to the position of the magnet 11.

The light emitting element 21 (irradiating unit, light emitting unit) irradiates the incremental pattern INC and the absolute pattern ABS of the scale S with light. The light receiving sensor 22 (photodetector) detects light emitted from the light emitting element 21 and passing through the incremental pattern INC, and light emitted from the light emitting element 21 and passed through the absolute pattern ABS. In FIG. 1, the angle detection unit 4 is a transmission type, and the light receiving sensor 22 detects the light transmitted through the scale S. The angle detection unit 4 may be of a reflection type, in which case the light receiving sensor 22 detects the light reflected by the scale S. The light receiving sensor 22 supplies a signal indicating the detection result to the processing unit 23. The processing unit 23 detects the angular position of the rotation axis SF by using the detection result of the light receiving sensor 22. For example, the processing unit 23 detects the angular position information of the first resolution by using the result of detecting the light from the absolute pattern ABS. Further, the processing unit 23 uses the result of detecting the light from the incremental pattern INC to perform an interpolation calculation on the angular position information of the first resolution, thereby performing the angular position information of the second resolution higher than the first resolution. Is detected.

In the present embodiment, the encoder device EC includes a signal processing unit 25. The signal processing unit 25 processes the detection result by the position detection unit 1. The signal processing unit 25 includes a synthesis unit 26 and an external communication unit 27. The synthesizing unit 26 acquires the angle position information of the second resolution detected by the processing unit 23. Further, the synthesis unit 26 acquires the multi-rotation information of the rotation axis SF from the storage unit 14 of the multi-rotation information detection unit 3. The synthesis unit 26 synthesizes the angle position information from the processing unit 23 and the multi-rotation information from the multi-rotation information detection unit 3, and calculates the rotation position information of the rotation axis SF. For example, when the detection result of the processing unit 23 is θ [rad] and the detection result of the multi-rotation information detection unit 3 is n rotations, the synthesis unit 26 uses (2π × n + θ) [rad] as the rotation position information. Is calculated. The rotation position information may be information that is a combination of multi-rotation information and angle position information of less than one rotation.

Then, the synthesis unit 26 transmits the calculated rotation position information to the external communication unit 27. The external communication unit 27 is communicably connected to the communication unit MC1 of the motor control unit MC by wire or wirelessly. The external communication unit 27 supplies digital rotation position information to the communication unit MC1 of the motor control unit MC. The motor control unit MC appropriately decodes the rotation position information from the external communication unit 27 of the angle detection unit 4. The motor control unit MC controls the rotation of the motor M by controlling the electric power (driving power) supplied to the motor M using the rotation position information.

The power supply unit 2 includes a signal generation unit 5, a switching unit 32, and a battery (battery) 33. The signal generation unit 5 generates an electric signal (detection signal) due to a change in the magnetic field accompanying the movement (eg rotation) of the moving unit (eg, rotation axis SF). This electrical signal includes, for example, a waveform in which electric power (current, voltage) changes with time. In the signal generation unit 5, for example, a detection signal is generated as an electric signal by a magnetic field that changes with the rotation of the rotation axis SF. For example, the signal generation unit 5 receives a detection signal due to a change in the magnetic field (magnetic field) formed by the magnet 11 used by the multi-rotation information detection unit 3 to detect the multi-rotation information of the rotation axis SF (eg, switching of the magnetic field). appear. The signal generation unit 5 is arranged so that the relative angular position with respect to the magnet 11 changes due to the rotation of the rotation axis SF. For example, when the relative position between the signal generating unit 5 and the magnet 11 becomes a predetermined position, the signal generating unit 5 generates a pulse-shaped electric signal.

The battery 33 supplies at least a part of the electric power consumed by the position detection unit 1 according to the detection signal generated by the signal generation unit 5. The battery 33 is, for example, a primary battery such as a button type battery or a dry battery, but may be a secondary battery such as a lithium ion secondary battery. The battery 33 of the present embodiment is, for example, a button type battery and is held by the holding portion 35. The holding unit 35 is, for example, a circuit board on which at least a part of the position detecting unit 1 is provided. The holding unit 35 holds, for example, a blocking unit 6, a processing unit 13, a switching unit 32, and a storage unit 14. The holding portion 35 is provided with, for example, a battery case capable of accommodating the battery 33, electrodes connected to the battery 33, wiring, and the like. The power supply unit 2 does not have to include the battery 33. For example, the power supply unit 2 includes electrodes, cases, and the like to which the battery 33 can be attached, and the user may attach the battery 33 to the encoder device EC when using the encoder device EC.

The switching unit 32 uses the detection signal generated by the signal generation unit 5 as a control signal to switch whether or not power is supplied from the battery 33 to the position detection unit 1. For example, the switching unit 32 starts supplying electric power from the battery 33 to the position detection unit 1 when the level of the electric signal generated by the signal generation unit 5 becomes equal to or higher than the threshold value. For example, the switching unit 32 starts supplying electric power from the battery 33 to the position detection unit 1 when the signal generation unit 5 generates a detection signal equal to or higher than the threshold value.

Further, the switching unit 32 stops the supply of electric power from the battery 33 to the position detection unit 1 when the level of the electric signal generated by the signal generation unit 5 becomes less than the threshold value. For example, the switching unit 32 stops the supply of electric power from the battery 33 to the position detection unit 1 when the detection signal generated by the signal generation unit 5 becomes less than the threshold value. For example, when a pulsed electric signal is generated in the signal generation unit 5, the switching unit 32 moves from the battery 33 to the position detection unit 1 when the level (potential) of the electric signal rises from a low level to a high level. The supply of electric power from the battery 33 to the position detection unit 1 is stopped after a predetermined time has elapsed from the change of the level (potential) of the electric signal to the low level.

Here, for example, in a state where the power supply from the first power source 7 is cut off (backup state), the time during which the power is supplied to the position detection unit 1 by the switching unit 32 (power supply time) is the signal detection unit. It changes depending on the magnitude of the pulsed detection signal generated from 5. For example, when the detection signal generated this time by the signal generation unit 5 has a higher power or level than the detection signal previously generated by the signal generation unit 5, the time for which the power is supplied to the position detection unit 1 according to the detection signal this time. Is longer than the time during which power is supplied to the position detection unit 1 in response to the previous detection signal. When the magnitude of the pulsed detection signal generated from the signal detection unit 5 varies in this way, the power supply unit 2 such as the battery 33 to the position detection unit 1 (eg, the processing unit 13 of the multi-rotation information detection unit 3) The power supply time at which power is supplied to) also varies. For example, if the power supply time is set according to the case where the detection signal is small (the power or level of the detection signal is low), the power supply time becomes long and extra power is consumed when the detection signal generated next is large. However, the cutoff unit 6 in the present embodiment receives a trigger signal indicating the end of the operation of the position detection unit 1 and shuts off the power supply from the power supply unit 2 to the position detection unit 1 to stop the power supply. It is possible to shorten the time for supplying power to the position detection unit 1 in response to the detection signal this time, and to suppress the consumption of the power supply unit (second power supply) such as the battery 33. The encoder device EC receives the trigger signal indicating the end of the operation of the position detection unit 1 and cuts off the power supply from the power supply unit 2 to the position detection unit 1, so that the power is supplied in real time (or for each detection signal). You can change the supply time.

The power supply unit 2 does not have to include the battery 33. For example, the power supply unit 2 includes electrodes, cases, and the like to which the battery 33 can be attached, and the user may attach the battery 33 to the encoder device EC when using the encoder device EC. Further, the power supply unit 2 does not have to include the battery 33 and the switching unit 32. For example, the power supply unit 2 may supply the power whose detection signal voltage is adjusted by a regulator or the like to the position detection unit 1. Further, the power supply unit 2 may supply the position detection unit 1 with the power adjusted by adjusting the voltage of the detection signal by a regulator or the like and the power from the battery 33 in combination or by switching.

FIG. 2 is a diagram showing a magnet 11, a magnetic sensor 12, and a signal generation unit 5 according to the present embodiment. FIG. 2A shows a perspective view of the magnet 11, the magnetic sensor 12, and the signal generation unit 5, and FIG. 2B shows the magnet 11, the magnetic sensor 12, and the signal generation as seen from the direction of the rotation axis SF. The plan view of the part 5 is shown. Further, FIG. 2C shows the circuit configuration of the first magnetic sensor 12a.

The magnet 11 is configured so that the direction and strength of the magnetic field in the radial direction (diameter direction) with respect to the rotation axis SF change with rotation. The magnet 11 is, for example, an annular member coaxial with the rotation axis SF. The main surfaces (front surface and back surface) of the magnet 11 are substantially perpendicular to the rotation axis SF, respectively. As shown in FIG. 2B, the magnet 11 is a permanent magnet magnetized to four poles. The magnet 11 has north and south poles arranged in the circumferential direction on the inner peripheral side and the outer peripheral side, respectively, and the phases of the magnet 11 are 180 ° out of phase between the inner peripheral side and the outer peripheral side. In the magnet 11, the boundary between the north pole and the south pole on the inner peripheral side substantially coincides with the boundary between the north pole and the south pole on the outer peripheral side in the circumferential direction (angle position).

In the following description, counterclockwise rotation is referred to as forward rotation and clockwise rotation is referred to as reverse rotation when viewed from the tip side (opposite side of the motor M in FIG. 1) of the rotating shaft SF. The forward rotation angle is represented by a positive value, and the reverse rotation angle is represented by a negative value. Note that the counterclockwise rotation when viewed from the base end side (motor M side in FIG. 1) of the rotation axis SF may be defined as forward rotation, and the clockwise rotation may be defined as reverse rotation.

Here, in the coordinate system fixed to the magnet 11, the angular position of one boundary between the N pole and the S pole in the circumferential direction is represented by the position 11a, and the angular position rotated by 90 ° from the position 11a is represented by the position 11b. Further, the angular position rotated by 90 ° from the position 11b is represented by the position 11c, and the position rotated by 90 ° from the position 11c is represented by the position 11d. The position 11c is an angular position of another boundary between the north pole and the south pole in the circumferential direction.

In the first section 180 ° counterclockwise from the position 11a, the north pole is arranged on the outer peripheral side of the magnet 11, and the south pole is arranged on the inner peripheral side of the magnet 11. In this first section, the radial direction of the magnetic field is generally the direction from the outer peripheral side to the inner peripheral side of the magnet 11. In the first section, the strength of the magnetic field is maximum at position 11b and minimum near position 11a and 11c.

In the second section 180 ° counterclockwise from the position 11c, the north pole is arranged on the inner peripheral side of the magnet 11, and the south pole is arranged on the outer peripheral side of the magnet 11. In this second section, the radial direction of the magnetic field is the direction from the inner peripheral side to the outer peripheral side of the magnet 11. In the second section, the strength of the magnetic field is maximum at position 11d and minimum near position 11a and 11c.

As described above, the radial direction of the magnetic field formed by the magnet 11 is reversed at the position 11a and reversed at the position 11c. The magnet 11 forms an alternating magnetic field in which the direction of the magnetic field in the radial direction is reversed as the magnet 11 rotates with respect to the coordinate system fixed to the outside of the magnet 11. The signal generation unit 5 is arranged at a position overlapping the magnet 11 when viewed from the normal direction of the main surface of the magnet 11.

In the present embodiment, the signal generation unit 5 includes a first signal generation unit 5a and a second signal generation unit 5b. The first signal generation unit 5a and the second signal generation unit 5b are units that generate electric signals, respectively, and are provided in non-contact with the magnet 11. The first signal generation unit 5a includes a first magnetic sensing unit 41 and a first power generation unit 42. The first magnetic sensitive unit 41 and the first power generation unit 42 are fixed to the outside of the magnet 11, and their relative positions on the magnet 11 change as the magnet 11 rotates. For example, in FIG. 2B, the position 11b of the magnet 11 is arranged at a position 45 ° counterclockwise from the first signal generating unit 5a, and the magnet 11 is forward (counterclockwise) from this state. When one rotation is made, the position 11b, the position 11c, the position 11d, and the position 11a pass in the vicinity of the signal generation unit 5 in this order.

The first magnetically sensitive portion 41 is a magnetically sensitive wire (magnetic material) such as a Wiegand wire. A large bulk Hausen jump (Weigand effect) occurs in the first magnetic sensitive portion 41 due to a change in the magnetic field accompanying the rotation of the magnet 11. The first magnetic sensitive portion 41 is a columnar member, and its axial direction is set to the radial direction of the magnet 11. When an alternating magnetic field is applied in the axial direction of the first magnetically sensitive portion 41 and the magnetic field is reversed, a domain wall is generated from one end to the other end in the axial direction.

The first power generation unit 42 is a high-density coil or the like that is wound around and arranged around the first magnetic sensitive unit 41. Electromagnetic induction occurs in the first power generation unit 42 with the generation of the domain wall in the first magnetic sensitive unit 41, and an induced current flows through the first power generation unit 42. When the position 11a or the position 11c of the magnet 11 shown in FIG. 2B passes in the vicinity of the signal generation unit 5, a pulsed current (electric signal) is generated in the first power generation unit 42. Further, the first power generation unit 42 can output a detection signal including a detection pulse such as a positive pulse or a negative pulse by using a large Barkhausen jump, and can output a detection signal from the outside (eg, the first power source 7 in FIG. 1). It can operate without power supply.

The direction of the current generated in the first power generation unit 42 changes according to the direction before and after the reversal of the magnetic field. For example, the direction of the current generated when reversing from the magnetic field facing the outside of the magnet 11 to the magnetic field facing inward is opposite to the direction of the current generated when reversing from the magnetic field facing the inside of the magnet 11 to the magnetic field facing outward. The electric power (induced current) generated in the first power generation unit 42 can be set by, for example, the number of turns of the high-density coil.

As shown in FIG. 2A, the first magnetic sensitive unit 41 and the first power generation unit 42 are housed in the case 43. The case 43 is provided with terminals 43a and 43b. One end of the high-density coil of the first power generation unit 42 is connected to the terminal 43a, and the other end is connected to the terminal 43b. The electric power generated by the first power generation unit 42 can be taken out to the outside of the first signal generation unit 5a via the terminals 43a and 43b.

The second signal generation unit 5b is arranged at an angle position that is greater than 0 ° and less than 180 ° from the angle position where the first signal generation unit 5a is arranged. The angle between the angular position of the first signal generating unit 5a and the angular position of the second signal generating unit 5b is selected from the range of 45 ° or more and 135 ° or less, and is about 90 ° in FIG. 2 (B). The second signal generation unit 5b has the same configuration as the first signal generation unit 5a. The second signal generation unit 5b includes a second magnetic sensitivity unit 45 and a second power generation unit 46. The second magnetic sensitive unit 45 and the second power generation unit 46 are the same as the first magnetic sensitive unit 41 and the first power generation unit 42, respectively, and the description thereof will be omitted. The second magnetic sensitive unit 45 and the second power generation unit 46 are housed in the case 47. The case 47 is provided with terminals 47a and 47b. The electric power generated by the second power generation unit 46 can be taken out to the outside of the second signal generation unit 5b via the terminals 47a and 47b.

The configuration of the signal generation unit 5 described above is an example, and the configuration can be changed as appropriate. For example, the signal generation unit 5 may generate electric power by electromagnetic induction that does not utilize the large Barkhausen jump (Wegand effect). Further, the number of power generation units included in the signal generation unit 5 can be appropriately changed, and may be, for example, one or three or more. Further, the arrangement of the signal generation unit 5 can be changed as appropriate.

The magnetic sensor 12 includes a first magnetic sensor 12a and a second magnetic sensor 12b. The first magnetic sensor 12a is arranged at an angle position larger than 0 ° and less than 90 ° with respect to the first magnetic sensitive unit 41 (first signal generation unit 5a) in the rotation direction of the rotation axis SF. The second magnetic sensor 12b is arranged at an angle position larger than 90 ° and less than 180 ° with respect to the first magnetic sensitive unit 41 (first signal generation unit 5a) in the rotation direction of the rotation axis SF.

As shown in FIG. 2C, the first magnetic sensor 12a is composed of a magnetoresistive element 51, a bias magnet (not shown) that applies a magnetic field of a constant strength to the magnetoresistive element 51, and a magnetoresistive element 51. It is equipped with a waveform shaping circuit (not shown) that shapes the waveform of. The magnetoresistive element 51 has a full bridge shape in which the element 52a, the element 52b, the element 52c, and the element 52d are connected in series. The signal line between the element 52a and the element 52c is connected to the power supply terminal 51p. The signal line between the element 52b and the element 52d is connected to the ground terminal 51g. The signal line between the element 52a and the element 52b is connected to the first output terminal 51a. The signal line between the element 52c and the element 52d is connected to the second output terminal 51b. The second magnetic sensor 12b has the same configuration as the first magnetic sensor 12a.

FIG. 3 is a diagram showing a circuit configuration of the power supply unit 2 and the multi-rotation information detection unit 3 according to the present embodiment. The power supply unit 2 includes a first signal generation unit 5a, a rectification stack 61, a second signal generation unit 5b, a rectification stack 62, a battery 33, and a cutoff unit 6. Further, the power supply unit 2 includes a regulator 63 as a switching unit 32 in FIG. 1.

The rectifier stack 61 is a rectifier that rectifies the current flowing from the first signal generation unit 5a. The first input terminal 61a of the rectifying stack 61 is connected to the terminal 43a of the first signal generation unit 5a. The second input terminal 61b of the rectifying stack 61 is connected to the terminal 43b of the first signal generation unit 5a. The ground terminal 61g of the rectifying stack 61 is connected to the ground wire GL to which the same potential as the signal ground SG is supplied. When the multi-rotation information detection unit 3 operates, the potential of the ground wire GL becomes the reference potential of the circuit 60. The output terminal 61c of the rectifying stack 61 is connected to the control terminal 63c of the regulator 63.

The rectifier stack 62 is a rectifier that rectifies the current flowing from the second signal generation unit 5b. The first input terminal 62a of the rectifying stack 62 is connected to the terminal 47a of the second signal generation unit 5b. The second input terminal 62b of the rectifying stack 62 is connected to the terminal 47b of the second signal generating unit 5b. The ground terminal 62g of the rectifying stack 62 is connected to the ground wire GL. The output terminal 62c of the rectifying stack 62 is connected to the control terminal 63c of the regulator 63.

The regulator 63 adjusts the electric power supplied from the battery 33 to the position detection unit 1 according to the on state and the off state of the regulator 63. The regulator 63 includes a first switching element 64 provided in a power supply path between the battery 33 and the position detection unit 1. The regulator 63 controls the operation of the first switching element 64 by using an electric signal (detection signal) generated by the signal generation unit 5 as a control signal (eg, enable signal).

The input terminal 63a of the regulator 63 is connected to the battery 33. The output terminal 63b of the regulator 63 is connected to the power supply line PL. The ground terminal 63g of the regulator 63 is connected to the ground wire GL. The control terminal 63c of the regulator 63 is an enable terminal, and the regulator 63 maintains the potential of the output terminal 63b at a predetermined voltage in a state where a voltage equal to or higher than the threshold value is applied to the control terminal 63c. The output voltage of the regulator 63 (the above-mentioned predetermined voltage) is, for example, 3V when the counting unit 67 is composed of CMOS or the like. The operating voltage of the storage unit 14 is set to, for example, the same voltage as a predetermined voltage. The predetermined voltage is a voltage required for power supply, and may be a constant voltage value or a voltage that changes stepwise.

The first switching element (first switch) 64 switches between continuity and interruption of the circuit 60 that supplies power to the position detection unit 1. The circuit 60 constitutes, for example, a power supply path connecting the first electrode (positive electrode) and the second electrode (negative electrode) of the second power source (eg, battery 33), and includes a power supply line PL and a ground line GL. The ground wire GL is connected to, for example, the negative electrode of the battery 33, and its potential becomes the reference potential of the circuit 60. The first switching element 64 switches, for example, whether or not power is supplied from the battery 33 to the position detection unit 1 via the circuit 60.

The regulator 63 uses an electric signal supplied from the signal generation unit 5 to the control terminal 63c as a control signal (enable signal), and is in a conduction state between the first terminal 64a and the second terminal 64b of the first switching element 64. Switch between (on state) and isolated state (off state). For example, the first switching element 64 includes a MOS, a TFT, and the like, the first terminal 64a and the second terminal 64b are a source electrode and a drain electrode, and the first control terminal 64c is a gate electrode.

The first control terminal 64c is charged by an electric signal (detection signal) generated by the signal generation unit 5. The first switching element 64 switches the circuit 60 to conduction according to the voltage of the first control terminal 64c. For example, the first switching element 64 interrupts the circuit 60 in a state where the potential of the first control terminal 64c is the reference potential of the circuit 60. Further, in the first switching element 64, when the voltage of the first control terminal 64c becomes equal to or higher than a predetermined value, the connection between the first terminal 64a and the second terminal 64b becomes a conductive state (on state). The circuit 60 is switched to conduction. When the space between the first terminal 64a and the second terminal 64b is turned on, power is supplied from the battery 33 to the circuit 60 via the power supply line PL and the ground line GL. The power supply unit 2 may include means for acquiring the on state and the off state of the regulator 63.

Further, the multi-rotation information detection unit 3 includes a first magnetic sensor 12a and a second magnetic sensor 12b. For example, the multi-rotation information detection unit 3 includes an analog comparator 65, an analog comparator 66, and a counting unit 67 as the processing unit 13 shown in FIG. The first magnetic sensor 12a and the second magnetic sensor 12b are sensors that detect the rotation axis SF, respectively. The first magnetic sensor 12a and the second magnetic sensor 12b detect the rotating shaft SF by detecting the magnetic field formed by the magnet 11 attached to the rotating shaft SF. The first magnetic sensor 12a and the second magnetic sensor 12b each detect the magnetic field formed by the magnet 11 by using the electric power supplied from the battery 33.

The power supply terminal 55p of the first magnetic sensor 12a is connected to the power supply line PL. The ground terminal 55g of the first magnetic sensor 12a is connected to the ground wire GL. The output terminal 55c of the first magnetic sensor 12a is connected to the input terminal 65a of the analog comparator 65. The output terminal 55c outputs, for example, a voltage corresponding to the difference between the potential of the second output terminal 51b shown in FIG. 2C and the reference potential.

The analog comparator 65 is a binarization unit that binarizes the voltage output from the first magnetic sensor 12a. The analog comparator 65 is, for example, a comparator, and compares the voltage output from the first magnetic sensor 12a with a predetermined voltage. The power supply terminal 65p of the analog comparator 65 is connected to the power supply line PL. The ground terminal 65g of the analog comparator 65 is connected to the ground wire GL. The output terminal 65b of the analog comparator 65 is connected to the first input terminal 67a of the counting unit 67. The analog comparator 65 outputs an H level signal from the output terminal when the output voltage of the first magnetic sensor 12a is equal to or higher than the threshold value, and outputs an L level signal from the output terminal when the output voltage is less than the threshold value.

The second magnetic sensor 12b and the analog comparator 66 have the same configuration as the first magnetic sensor 12a and the analog comparator 65. The power supply terminal 56p of the second magnetic sensor 12b is connected to the power supply line PL. The ground terminal 56g of the second magnetic sensor 12b is connected to the ground wire GL. The output terminal 56c of the second magnetic sensor 12b is connected to the input terminal 66a of the analog comparator 66. The power supply terminal 66p of the analog comparator 66 is connected to the power supply line PL. The ground terminal 66g of the analog comparator 66 is connected to the ground wire GL. The output terminal 66b of the analog comparator 66 is connected to the second input terminal 67b of the counting unit 67. The analog comparator 66 outputs an H level signal from the output terminal when the output voltage of the second magnetic sensor 12b is equal to or higher than the threshold value, and outputs an L level signal from the output terminal 66b when the output voltage is lower than the threshold value.

The counting unit 67 counts the multi-rotation information of the rotating shaft SF by using the electric power supplied from the battery 33. The counting unit 67 includes, for example, a CMOS logic circuit. The counting unit 67 operates by using the electric power supplied through the power supply terminal 67p and the ground terminal 67g. The power supply terminal 67p of the counting unit 67 is connected to the power supply line PL. The ground terminal 67g of the counting unit 67 is connected to the ground wire GL. The counting unit 67 performs counting processing using the voltage supplied via the first input terminal 67a and the voltage supplied via the second input terminal 67b as control signals.

The storage unit 14 stores at least a part (eg, multi-rotation information) of the rotation position information detected by the processing unit 13 using the electric power supplied from the battery 33 (performs a writing operation). The storage unit 14 stores the result of counting by the counting unit 67 (multi-rotation information) as the rotation position information detected by the processing unit 13. The power supply terminal 14p of the storage unit 14 is connected to the power supply line PL. The ground terminal 14g of the storage unit 14 is connected to the ground wire GL. The storage unit 14 includes, for example, a non-volatile memory, and can hold information written while power is being supplied even in a state where power is not supplied. The multi-rotation information detection unit 3 may include means for acquiring the on state and the off state of the regulator 63.

In the present embodiment, a capacitor 69 is provided between the rectifying stack 61, the rectifying stack 62, and the regulator 63. The first electrode 69a of the capacitor 69 is connected to a signal line connecting the rectifying stack 61, the rectifying stack 62, and the control terminal 63c of the regulator 63. The second electrode 69b of the capacitor 69 is connected to the ground wire GL. The capacitor 69 is, for example, a smoothing capacitor, which reduces pulsation and reduces the load on the regulator. The constant of the capacitor 69 is such that the power supply from the battery 33 to the processing unit 13 and the storage unit 14 is maintained during the period from the detection of the rotation position information by the processing unit 13 to the writing of the rotation position information to the storage unit 14. Is set to.

Further, the multi-rotation information detection unit 3 includes a delay unit 70. The delay unit 70 starts supplying power to the processing unit 13 of the multi-rotation information detection unit 3 (for example, a delay signal delayed by a predetermined time with respect to the start of power supply from the power supply unit 2 to the position detection unit 1. (Delay signal delayed by a predetermined time from the time) is generated. The power supply terminal 70p of the delay unit 70 is connected to the power supply line PL. The ground terminal 70g of the delay portion 70 is connected to the ground wire GL. The delay unit 70 is, for example, a delay circuit including a resistance element and a capacitor element. The time constant of the delay unit 70 is set to be longer than the time required for the processing unit 13 to perform processing.

The delay unit 70 outputs a delay signal to each of the processing unit 13 and the blocking unit 6, which will be described later with reference to FIGS. 4 to 6. The delay signal is, for example, a reset signal for asynchronous reset in the position detection unit 1 (processing unit 13 of the multi-rotation information detection unit 3), and is a reset of the processing unit 13 (eg, data reset, processing procedure reset, etc.). Used for. In this case, the processing unit 13 of the position detection unit 1 receives the delay signal, resets the processing unit 13, and starts the operation. Then, the processing unit 13 outputs a trigger signal (eg, operation end signal, access end signal) to the cutoff unit 6 (eg, logic circuit 79) when the operation is terminated. For example, the processing unit 13 (eg, counting unit 67) outputs a trigger signal to the blocking unit 6 when the access to the storage unit 14 (eg, memory access) is completed. By using the delay signal in such a configuration, a trigger that tends to occur immediately after the start of power supply to the processing unit 13 in the logic circuit 79 of the cutoff unit 6 (for example, at the same time when the power supply to the processing unit 13 is turned on) is likely to occur. It is possible to determine the incorrect output of the signal.

The cutoff unit 6 receives a trigger signal and a delay signal indicating the end of the operation of the position detection unit 1 (eg, multi-rotation information detection unit 3), and receives a trigger signal and a delay signal from the power supply unit 2 to the position detection unit 1 (eg, multi-rotation information detection). Cut off the power supply to part 3). The cutoff unit 6 is, for example, a part of the power supply unit 2, but may be provided in a portion other than the power supply unit 2. The cutoff unit 6 is connected to, for example, a node n1 on the signal line 71 and a node n2 on the ground line GL. The signal line 71 is a signal line between the signal generation unit 5 and the regulator 63. For example, the first end of the signal line 71 is connected to the output terminal 61c of the rectifying stack 61, and the second end thereof is connected to the control terminal 63c of the regulator 63. The cutoff unit 6 may cut off the power supply to the position detection unit 1 (in this case, the multi-rotation information detection unit 3) in response to the trigger signal.

The cutoff unit 6 controls the first switching element 64 by receiving the trigger signal and the delay signal. For example, the cutoff unit 6 receives a trigger signal and a delay signal to discharge the first control terminal 64c in a state where the first control terminal 64c of the first switching element 64 is charged. For example, when the blocking unit 6 receives the trigger signal and the delay signal, the electric charge of the first control terminal 64c is discharged by releasing the electric charge of the first control terminal 64c to the ground wire GL based on the discharge control signal. In the first switching element 64, the first control terminal 64c is discharged, so that the first terminal 64a and the second terminal 64b are in an insulated state (off state). The first switching element 64 cuts off the supply of electric power from the battery 33 to the position detection unit 1 (multi-rotation information detection unit 3) by turning off the space between the first terminal 64a and the second terminal 64b. ..

4 to 6 are views showing a blocking unit and its operation according to the embodiment. The cutoff unit 6 receives, for example, a trigger signal from the processing unit 13 and a delay signal from the delay unit 70, and receives a power supply unit 2 (eg, battery 33) from the power supply unit 2 (eg, battery 33) to the position detection unit 1 (eg, processing unit 13). Cut off the power supply. For example, the power supply unit 2 supplies power to the position detection unit 1 in response to the generation of the detection signal, and the cutoff unit 6 includes a discharge circuit 74 that discharges the detection signal. The discharge circuit 74 discharges the conductive member (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) charged by the detection signal. The discharge circuit 74 in this embodiment includes a second switching element 75, a signal generation unit 76, and a charge holding unit 77.

The second switching element 75 switches between conduction and interruption between the ground wire GL, which is the reference potential of the circuit 60, and the first control terminal 64c of the first switching element 64. The second switching element 75 includes, for example, a MOS or FET, and includes a first terminal 75a, a second terminal 75b (source electrode, drain electrode), and a second control terminal 75c (gate electrode). The first terminal 75a of the second switching element 75 is connected to the signal line 71 between the signal generation unit 5 and the regulator 63. The second terminal 75b is connected to the ground wire GL. The second control terminal 75c is connected to the signal generation unit 76. The second control terminal 75c is charged by the control signal generated by the signal generation unit 76. When the second control terminal 75c is charged, the second switching element 75 switches between the ground wire GL and the control terminal 63c of the regulator 63 to be conductive, and the first control of the first switching element 64 (see FIG. 3). The connection is switched between the terminal 64c and the ground wire GL.

The signal generation unit 76 receives the trigger signal and generates a control signal for controlling the second switching element 75. The signal generation unit 76 includes a third switching element 78 and a logic circuit 79. The logic circuit 79 receives the trigger signal and generates a control signal for controlling the third switching element 78. The logic circuit 79 includes a first input terminal 79a, a second input terminal 79b, and an output terminal 79c. The first input terminal 79a is connected to the terminal 70a of the delay portion 70. A delay signal is input from the delay unit 70 to the first input terminal 79a. The second input terminal 79b is connected to the terminal 13a of the processing unit 13. A trigger signal is input from the processing unit 13 to the second input terminal 79b. The output terminal 79c is connected to the third control terminal 78c of the third switching element 78. The logic circuit 79 is, for example, an AND circuit, and generates a control signal that becomes a high level when a trigger signal and a delay signal are received. For example, in the logic circuit 79, when the first input terminal 79a becomes a high level (H) and the second input terminal 79b becomes a high level (H), the output terminal 79c switches to a high level (H). ..

The third switching element 78 switches between continuity and interruption between the second control terminal 75c of the second switching element 75 and the signal line 71 through which the detection signal is transmitted. The third switching element 78 includes, for example, a MOS or FET, and includes a first terminal 78a, a second terminal 78b (source electrode, drain electrode), and a third control terminal 78c (gate electrode). The first terminal 78a of the third switching element 78 is connected to the signal line 71. The second terminal 78b is connected to the ground wire GL via the charge holding portion 77. The third control terminal 78c is connected to the output terminal 79c of the logic circuit 79. The third control terminal 78c is charged by the control signal generated by the logic circuit 79. For example, the third control terminal 78c is charged when the output terminal 79c of the logic circuit 79 reaches a high level.

The charge holding unit 77 is provided on the signal line 80 between the second control terminal 75c of the second switching element 75 and the ground wire GL, and holds the charge for charging the second control terminal 75c. The charge holding unit 77 includes, for example, a delay circuit, and includes a resistance element 81 and a capacitor element 82. The first end of the resistance element 81 is connected to the signal line 80, and the second end is connected to the ground line GL. In the capacitor element 82, the first electrode is connected to the signal line 80, and the second electrode is connected to the ground line GL.

Next, as an example, the operation of the blocking unit 6 in the backup state will be described. In FIG. 4A, the signal line 71 is supplied with the detection signal SG1 generated by the signal generation unit 5 shown in FIGS. 1 and 2. The detection signal SG1 in FIG. 4A is, for example, a detection signal rectified by the rectifying stack 61 in FIG. The control terminal 63c of the regulator 63 (the first control terminal 64c of the first switching element 64 in FIG. 3) is charged by the detection signal SG1. When the voltage of the control terminal 63c becomes equal to or higher than the threshold value, the first switching element 64 of FIG. 3 is turned on. When the first switching element 64 is turned on, power PW is supplied from the battery 33 to the multi-rotation information detection unit 3 via the regulator 63, as shown in FIG. 4 (B).

When the power PW is supplied to the multi-rotation information detection unit 3, the delay unit 70 transmits the delay signal DS delayed with respect to the start of the power PW supply to the processing unit 13 and the processing unit 13, as shown in FIG. 4C. Output to each of the cutoff units 6. Upon receiving the delay signal DS, the processing unit 13 starts an operation related to one detection of the multi-rotation information. When the power PW is supplied to the multi-rotation information detection unit 3 and the processing unit 13 receives the delay signal DS, the magnetic sensor 12 (see FIG. 3) executes detection using the power PW and processes the detection result. Output to 13. Then, the processing unit 13 processes the detection result of the magnetic sensor 12 using the electric power PW, and outputs the multi-rotation information D1 (see FIG. 5A) to the storage unit 14 as the processing result. Further, the storage unit 14 performs a writing operation of the multi-rotation information D1 by using the electric power PW. When the processing unit 13 completes the access to the storage unit 14, as shown in FIG. 5 (B), the processing unit 13 operates the position detection unit 1 (eg, the multi-rotation information detection unit 3) (eg, one detection). A trigger signal TG indicating the end of the storage of the multi-rotation information regarding the above (stored in the storage unit 14) is output to the blocking unit 6.

Further, as shown in FIG. 5C, the blocking unit 6 is in a state in which the trigger signal TG and the delay signal DS are input. For example, in the logic circuit 79, the first input terminal 79a is raised to a high level by the delay signal DS, and the second input terminal 79b is raised to a high level by the trigger signal TG. As shown in FIG. 6A, the logic circuit 79 outputs the control signal SG2 from the output terminal 79c when the first input terminal 79a and the second input terminal 79b are at high levels, respectively (the output terminal 79c is). To a high level). In the third switching element 78, the third control terminal 78c is charged by the control signal SG2 from the logic circuit 79, and the connection between the first terminal 78a and the second terminal 78b is switched to conduction.

When the connection between the first terminal 78a and the second terminal 78b is switched to conduction, as shown in FIG. 6B, the signal line 71 or the control terminal 63c of the regulator 63 is discharged via the third switching element 78. The control signal SG3 is output. The discharge control signal SG3 is a signal caused by the electric charge of the detection signal. The discharge control signal SG3 is a signal caused by the electric charge accumulated in the conductive member (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) charged by the detection signal. Therefore, when the discharge control signal SG3 is output from the signal line 71, the conductive member charged by the detection signal (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) is discharged. .. The discharge control signal SG3 is output to the second control terminal 75c of the second switching element 75 via the third switching element 78.

In the second switching element 75, the second control terminal 75c is charged by the discharge control signal SG3, and the connection between the first terminal 75a and the second terminal 75b is switched to conduction. Then, as shown in FIG. 6C, a current Ix flows from the control terminal 63c of the regulator 63 to the ground wire GL via the second switching element 75. The current Ix is a current caused by the electric charge of the conductive member (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) charged by the detection signal. The conductive member charged by the detection signal (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) is in a state where the first switching element 64 (see FIG. 3) is turned off by the current Ix flowing through it. The voltage drops (discharges) to the level where

Further, the charge holding unit 77 holds the charge of the control signal SG3 (delays the control signal SG3) until the first switching element 64 (see FIG. 3) is turned off. The regulator 63 cuts off the supply of electric power from the battery 33 to the multi-rotation information detection unit 3 when the first switching element 64 (see FIG. 3) is turned off.

Next, regarding the operations of the power supply unit 2 and the multi-rotation information detection unit 3, the operation of the multi-rotation information detection unit 3 when the rotation axis SF rotates counterclockwise (forward rotation) will be typically described. FIG. 7 is a timing chart showing the operation of the multi-rotation information detection unit 3 when the rotation axis SF rotates counterclockwise (forward rotation).

In the "magnetic field" of FIG. 7, the solid line indicates the magnetic field at the position of the first signal generation unit 5a, and the broken line indicates the magnetic field at the position of the second signal generation unit 5b. The "first signal generation unit" and "second signal generation unit" indicate the output of the first signal generation unit 5a and the output of the second signal generation unit 5b, respectively, and output the current flowing in one direction. The output of the current flowing in the opposite direction was set to negative (-). The "enable signal" indicates the potential applied to the control terminal 63c of the regulator 63 by the electric signal generated by the signal generation unit 5, the high level is represented by "H", and the low level is represented by "L". “Regulator” indicates the output of the regulator 63, where the high level is represented by “H” and the low level is represented by “L”.

In the "first magnetic sensor" and "second magnetic sensor" of FIG. 7, the outputs of the first magnetic sensor 12a and the second magnetic sensor 12b are shown by solid lines, respectively. In the "first magnetic sensor" and "second magnetic sensor", the dotted line is the output when the sensor is constantly driven. The "first analog comparator" and the "second analog comparator" indicate the outputs from the analog comparator 65 and the analog comparator 66, respectively.

The first signal generation unit 5a outputs a current pulse (negative of the “first signal generation unit”) flowing in the opposite direction at an angle position of 135 °. Further, the first signal generation unit 5a outputs a current pulse (positive of the "first signal generation unit") flowing in the forward direction at the angle position of 315 °. The second signal generation unit 5b outputs a current pulse (positive of the “second signal generation unit”) flowing in the forward direction at an angle position of 45 °. Further, the second signal generation unit 5b outputs a current pulse (negative of the “second signal generation unit”) flowing in the opposite direction at the angle position of 225 °. Therefore, the enable signal switches to a high level at each of the angle position 45 °, the angle position 135 °, the angle position 225 °, and the angle position 315 °. Further, the regulator 63 has a predetermined voltage on the power supply line PL at each of the angle position 45 °, the angle position 135 °, the angle position 225 °, and the angle position 315 °, corresponding to the state in which the enable signal is maintained at a high level. Supply.

In the present embodiment, the output of the first magnetic sensor 12a and the output of the second magnetic sensor 12b have a phase difference of 90 °, and the processing unit 13 detects the rotation position information by using this phase difference. To do. The output of the first magnetic sensor 12a has a positive sine wave shape in the range from the angle position 0 ° to the angle position 180 °. In this angular range, the regulator 63 outputs power at an angular position of 45 ° and an angular position of 135 °. The first magnetic sensor 12a and the analog comparator 65 are driven by the electric power supplied at the angle position 45 ° and the angle position 135 °, respectively. The signal output from the analog comparator 65 (hereinafter referred to as A-phase signal) is maintained at the L level in a state where power is not supplied, and becomes the H level at each of the angle position 45 ° and the angle position 135 °. ..

Further, the output of the second magnetic sensor 12b has a positive sine wave shape in the range from the angle position 270 ° (−90 °) to the angle position 90 °. In this angular range, the regulator 63 outputs power at an angular position of 315 ° (−45 °) and an angular position of 45 °. The second magnetic sensor 12b and the analog comparator 66 are driven by the electric power supplied at the angle position 315 ° and the angle position 45 °, respectively. The signal output from the analog comparator 66 (hereinafter referred to as B-phase signal) is maintained at the L level in a state where power is not supplied, and becomes the H level at each of the angle position 315 ° and the angle position 45 °. ..

Here, when the A-phase signal supplied to the counting unit 67 is the H level (H) and the B-phase signal supplied to the counting unit 67 is the L level, a set of these signal levels is set (H, L). ). In FIG. 7, the signal level set is (L, H) at the angle position 315 °, the signal level set is (H, H) at the angle position 45 °, and the signal level set is (H, H) at the angle position 135 °. , L).

The counting unit 67 stores a set of signal levels in the storage unit 14 when one or both of the A-phase signal and the B-phase signal detected by the magnetic sensor 12 are at the H level. When one or both of the A-phase signal and the B-phase signal detected next are at the H level, the counting unit 67 reads the previous level set from the storage unit 14, and reads the previous level set and the current level set. The rotation direction is determined by comparing with the set.

For example, when the previous signal level set is (H, H) and the current signal level is (H, L), the angle position is 45 ° in the previous detection, and the angle is in the current detection. Since the position is 135 °, it can be seen that it is counterclockwise (forward rotation). When the current level set is (H, L) and the previous level set is (H, H), the counting unit 67 sends an up signal indicating that the counter is up to the storage unit 14. Supply. When the storage unit 14 detects the up signal from the counting unit 67, the storage unit 14 updates the stored multi-rotation information to a value incremented by 1. The multi-rotation information detection unit 3 according to the present embodiment can detect multi-rotation information while determining the rotation direction of the rotation axis SF.

FIG. 8 is a diagram showing an example of a detection signal, an enable signal, a delay signal, and a discharge control signal according to the embodiment. In FIG. 8, the vertical axis is the level (voltage) of each signal, and the horizontal axis is the time. The “detection signal” is a signal generated in the signal generation unit 5 (see FIG. 3). The level of the "detection signal" increases from time t1. The “power” is a power PW supplied from the regulator 63 (FIG. 4B) using the detection signal as a control signal (enable signal). The "electric power" rises at time t1 and its level becomes almost constant. The “delay signal” is a signal generated by the delay unit 70 (see FIG. 5B) using the power PW from the battery 33. The slope of the "delay signal" as the level rises is gentler than that of the "power". The processing unit 13 (see FIG. 5B) starts processing when the “delay signal” reaches a predetermined level (threshold value) as a trigger.

The “discharge control signal” is a control signal output to the second control terminal 75c of the second switching element 75 (see FIG. 6B). The "discharge control signal" is output to the second control terminal 75c by outputting the delay signal DS and the trigger signal TG to the delay unit 70 (see FIG. 6A). The "discharge control signal" reaches a predetermined level (threshold value) at time t2, and the second switching element 75 is turned on. When the second switching element 75 is turned on, the voltage of the control terminal 63c of the regulator 63 drops, and the level of "power" drops. The level of "electric power" becomes almost 0 at time t3. Further, as the level of "electric power" decreases, the level of "delay signal" generated by the delay unit 70 decreases. Further, the level of the "detection signal" is lowered by discharging the electric charge via the second switching element 75 (see FIG. 6C). The level of the "discharge control signal" is lowered with respect to the "detection signal" because the charge is held by the charge holding unit 77 (FIG. 6B).

Next, FIG. 9 is a diagram showing a modified example of the blocking unit 6 according to the embodiment. The third switching element 78 shown in FIG. 4A is omitted from the blocking unit 6 shown in FIG. 9A. The cutoff unit 6 includes a logic circuit 79 and a rectifying element 85. The logic circuit 79 receives the trigger signal TG output from the processing unit 13 and generates a control signal for controlling the second switching element 75. The output terminal 79c of the logic circuit 79 is connected to the signal line 86. The rectifying element 85 is provided on the signal line 86 between the logic circuit 79 and the second control terminal 75c of the second switching element 75. The rectifying element 85 is, for example, a diode, which passes a current in a predetermined direction and cuts off a current in the opposite direction. For example, the rectifying element 85 suppresses the flow of current from the charge holding unit 77 to the logic circuit 79. In such a blocking unit 6, the second control terminal 75c is charged by the control signal (in this case, the discharge control signal) output from the logic circuit 79, and the second switching element 75 is turned on. When the second switching element 75 is turned on, the blocking unit 6 discharges the conductive member (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) charged by the detection signal. , The power supply from the battery 33 is cut off. The discharge circuit 74 in this embodiment includes a second switching element 75, a signal generation unit 76 including a logic circuit 79 and a rectifier element 85, and a charge holding unit 77.

As described above, the blocking unit 6 does not have to include the third switching element 78 of FIG. In FIG. 9, the power of the control signal supplied to the second control terminal 75c of the second switching element 75 is covered by the power supplied from the battery 33. In the cutoff unit 6 of FIG. 6B, the power of the control signal supplied to the second control terminal 75c of the second switching element 75 is covered by the power of the detection signal, for example, the consumption of the battery 33 is reduced. ..

In the blocking section 6 of FIG. 9B, the charge holding section 77 and the rectifying element 85 of FIG. 9A are omitted. The logic circuit 79 receives the trigger signal TG output from the processing unit 13 and generates a control signal for controlling the second switching element 75. The output terminal 79c of the logic circuit 79 is connected to the second control terminal 75c of the second switching element 75. In the cutoff unit 6, the second control terminal 75c is charged by the control signal (in this case, the discharge control signal) output from the logic circuit 79, and the second switching element 75 is turned on. When the second switching element 75 is turned on, the blocking unit 6 discharges the conductive member (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) charged by the detection signal. , The power supply from the battery 33 is cut off. As described above, the blocking unit 6 does not have to include the charge holding unit 77. The cutoff unit 6 of FIG. 9B may include a capacitor element on the output side of the regulator 63 (for example, the input side of the logic circuit 79), and by holding power in this capacitor element, the logic circuit The time for which the control signal is output from 79 may be extended. The discharge circuit 74 in this embodiment includes a second switching element 75 and a signal generation unit 76 including a logic circuit 79.

The second switching element 75 shown in FIG. 9B is omitted from the blocking unit 6 shown in FIG. 9C. The logic circuit 79 is connected to the node Nc of the signal line 71 through which the detection signal is transmitted and the node Nd on the ground line GL, respectively. The output terminal 79c of the logic circuit 79 is connected to the ground wire GL. The logic circuit 79 outputs the generated control signal to the ground wire GL via the output terminal 79c. The logic circuit 79 receives the trigger signal TG and the delay signal DS, and switches between the node Nc and the output terminal 79c to be conductive. The cutoff unit 6 connects the node Nc and the output terminal 79c so that the conductive member charged by the detection signal (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) is connected. It is discharged to cut off the power supply from the battery 33. As described above, the blocking unit 6 does not have to include the second switching element 75. The discharge circuit 74 in this embodiment includes a logic circuit 79.

In the encoder device EC according to the present embodiment, power is supplied from the battery 33 to the multi-rotation information detection unit 3 within a short time after the electric signal is generated in the signal generation unit 5, and the multi-rotation information detection unit 3 Dynamic drive (intermittent drive). When the operation of the multi-rotation information detection unit 3 is completed, the cutoff unit 6 is discharged by discharging the conductive member (eg, the electrode of the capacitor 69, the first control terminal 64c of the first switching element 64) charged by the detection signal. The power supply from the battery 33 to the multi-rotation information detection unit 3 is cut off. The cutoff unit 6 reduces the frequency of maintenance for replacing the battery 33, for example, by shortening the time for supplying electric power from the battery 33 to the multi-rotation information detection unit 3 and reducing the consumption of the battery 33. This contributes to eliminating the maintenance of replacing the battery 33.

After the detection and writing of the multi-rotation information is completed, the power supply to the multi-rotation information detection unit 3 is cut off, but the count value is stored because it is stored in the storage unit 14. Such a sequence is repeated every time a predetermined position on the magnet 11 passes near the signal generating unit 5 even when the power supply from the outside is cut off. Further, the multi-rotation information stored in the storage unit 14 is read out by the motor control unit MC or the like the next time the motor M is started, and is used for calculating the initial position of the rotation axis SF and the like. In such an encoder device EC, the battery 33 supplies at least a part of the electric power consumed by the position detection unit 1 (eg, the multi-rotation information detection unit 3) according to the electric signal generated by the signal generation unit 5. Therefore, the battery 33 can have a long life. Maintenance (eg, replacement) of the battery 33 can be eliminated or the frequency of maintenance can be reduced. For example, if the life of the battery 33 is longer than the life of other parts of the encoder device EC, it is possible to eliminate the need to replace the battery 33.

Further, when a magnetically sensitive wire such as a Wiegand wire is used, a pulse current output can be obtained from the signal generation unit 5 even if the magnet 11 rotates at an extremely low speed. Therefore, for example, in a state where power is not supplied to the motor M, the output of the signal generating unit 5 can be used as an electric signal even when the rotation of the rotating shaft SF (magnet 11) is extremely low.

The multi-rotation information detection unit 3 is a magnetic detection unit in the above embodiment, but may be an optical detection unit (eg, reflected light or transmitted light). In this case, a part of the multi-rotation information detection unit 3 may be shared with the angle detection unit 4. Further, for example, the multi-rotation information detection unit 3 is an optical detection unit, and the light emission timing of the light source (eg, the irradiation timing of the light emitted to detect the multi-rotation information) is output from the signal generation unit 5. When controlled by a pulsed electric signal (detection signal), the operating period of the position information detection unit 1 (eg, multi-rotation information detection unit 3) described above includes a period of light emission by the electric signal. Further, the power supply unit 2 may use the power of the detection signal generated by the signal generation unit 5 as the power source. For example, the power supply unit 2 may not include the battery 33, and may adjust the voltage of the detection signal to a predetermined voltage by a regulator or the like and supply the power of the detection signal to the position detection unit 1. Further, in the above-described embodiment, the signal generation unit 5 generates a detection signal when the magnet 11 has a predetermined positional relationship. The encoder device EC (multi-rotation information detection unit 3) may include a signal generation unit 5 as a sensor for detecting the position information of the rotation axis SF (magnet 11).

[Drive]
Next, the drive device according to the embodiment will be described. FIG. 10 is a diagram showing an example of the drive device MTR. In the following description, the same or equivalent components as those in the above-described embodiment are designated by the same reference numerals, and the description will be omitted or simplified. This drive device MTR is a motor device including an electric motor. The drive device MTR has a rotation axis SF, a main body (drive unit) BD that rotationally drives the rotation axis SF, and an encoder device EC that detects rotation position information of the rotation axis SF.

In FIG. 10, the magnet 11 is provided on the same rotating member (scale S) as the incremental pattern INC and the absolute pattern ABS. The magnet 11 is arranged on the scale S on the same side as the incremental pattern INC and the absolute pattern ABS. The signal generation unit 5 is arranged on the same side as the light emitting element 21 and the light receiving sensor 22 with respect to the scale S. The arrangement of the magnet 11, the signal generating unit 5, the scale S, the light emitting element 21, and the light receiving sensor 22 is not limited to the arrangement shown in FIG. 10, and may be, for example, the arrangement shown in FIG. 1 or any other arrangement. Good.

The rotating shaft SF has a load-side end SFa and a non-load-side end SFb. The load side end SFa is connected to another power transmission mechanism such as a speed reducer. The scale S is fixed to the counterload side end SFb via the fixing portion. Along with fixing the scale S, an encoder device EC is attached. The encoder device EC is an encoder device according to the above-described embodiment, modification, or combination thereof.

In this drive device MTR, the motor control unit MC shown in FIG. 1 or the like controls the main body unit BD using the detection result of the encoder device EC. Since the drive device MTR has no or low need for battery replacement of the encoder device EC, the maintenance cost can be reduced. The drive device MTR is not limited to the motor device, and may be another drive device having a shaft portion that rotates using hydraulic pressure or pneumatic pressure.

[Stage device]
Next, the stage device will be described. FIG. 11 is a diagram showing a stage device STG. This stage device STG has a configuration in which a stage (rotary table TB, moving object) is attached to the load side end SFa of the rotation axis SF of the drive device MTR shown in FIG. The stage device STG may be configured to linearly move the stage in one direction by, for example, a one-dimensional linear motor. Further, the stage device STG may be configured to move the stage in two directions by a plurality of one-dimensional linear motors or two-dimensional linear motors (eg, a flat motor). In the following description, the same or equivalent components as those in the above-described embodiment are designated by the same reference numerals, and the description will be omitted or simplified.

When the stage device STG drives the drive device MTR to rotate the rotation shaft SF, this rotation is transmitted to the rotary table TB. At that time, the encoder device EC detects the angular position of the rotation axis SF and the like. Therefore, the angular position of the rotary table TB can be detected by using the output from the encoder device EC. A speed reducer or the like may be arranged between the load side end SFa of the drive device MTR and the rotary table TB.

Since the stage device STG requires less or no battery replacement for the encoder device EC, maintenance costs can be reduced. The stage device STG can be applied to, for example, a rotary table provided in a machine tool such as a lathe.

[Robot device]
Next, the robot device will be described. FIG. 12 is a perspective view showing the robot device RBT. Note that FIG. 12 schematically shows a part (joint portion) of the robot device RBT. In the following description, the same or equivalent components as those in the above-described embodiment are designated by the same reference numerals, and the description will be omitted or simplified. This robot device RBT has a first arm AR1, a second arm AR2, and a joint portion JT. The first arm AR1 is connected to the second arm AR2 via the joint JT.

The first arm AR1 includes an arm portion 101, a bearing 101a, and a bearing 101b. The second arm AR2 has an arm portion 102 and a connecting portion 102a. The connecting portion 102a is arranged between the bearing 101a and the bearing 101b in the joint portion JT. The connecting portion 102a is provided integrally with the rotating shaft SF2. The rotary shaft SF2 is inserted into both the bearing 101a and the bearing 101b at the joint portion JT. The end of the rotating shaft SF2 on the side inserted into the bearing 101b penetrates the bearing 101b and is connected to the speed reducer RG.

The speed reducer RG is connected to the drive device MTR, and reduces the rotation of the drive device MTR to, for example, 1/100 or the like and transmits it to the rotation shaft SF2. Although not shown in FIG. 12, the load-side end SFa of the rotation shaft SF of the drive device MTR is connected to the speed reducer RG. Further, a scale S of the encoder device EC is attached to the counterload side end SFb of the rotation axis SF of the drive device MTR.

When the robot device RBT drives the drive device MTR to rotate the rotation shaft SF, this rotation is transmitted to the rotation shaft SF2 via the speed reducer RG. The rotation of the rotation shaft SF2 causes the connection portion 102a to rotate integrally, whereby the second arm AR2 rotates with respect to the first arm AR1. At that time, the encoder device EC detects the angular position of the rotation axis SF and the like. Therefore, the angular position of the second arm AR2 can be detected by using the output from the encoder device EC.

Since the robot device RBT does not require or reduces the need for battery replacement of the encoder device EC, the maintenance cost can be reduced. Further, although the encoder device EC performs the detection operation intermittently, the robot device RBT is not limited to the above configuration, and the drive device MTR can be applied to various robot devices having joints.

The technical scope of the present invention is not limited to the embodiments described in the above-described embodiments. One or more of the requirements described in the above embodiments and the like may be omitted. In addition, the requirements described in the above-described embodiments can be combined as appropriate. In addition, to the extent permitted by law, the disclosure of all documents cited in the above-mentioned embodiments and the like shall be incorporated as part of the description in the main text.

1 ... position detection unit, 2 ... power supply unit, 3 ... multi-rotation information detection unit, 5 ... signal generation unit, 6 ... cutoff unit, 7 ... first power supply, 11 ... magnet, 12 ... magnetic sensor, 13 ... processing unit, 14 ... storage unit, 64 ... first switching element, 64c ... first control terminal, 70 ... delay unit , 71 ... Signal line, 74 ... Discharge circuit, 75 ... Second switching element, 75c ... Second control terminal, 76 ... Signal generator, 77 ... Charge holding unit, 78 ... 3rd switching element, 78c ... 3rd control terminal, 79 ... Logic circuit, 85 ... Rectifier element, EC ... Encoder device, TB ... Rotating table (stage), MTR ...・ ・ Drive device, RBT ・ ・ ・ Robot device, SF ・ ・ ・ Rotating axis (moving part), STG ・ ・ ・ Stage device

In the first aspect of the present invention, an encoder device is provided. The encoder device may comprise a position detector for detecting the position information of the mobile unit. The encoder apparatus, the move of the mobile unit thus may comprise a signal generator Ru to generate electrical signals. Encoder apparatus, based on the electrical signal may comprise a switching unit that you switch the presence or absence of supply of power to the front Symbol position detector. In the second aspect of the present invention, a drive device is provided. The drive device may include the encoder device as described above. The drive device may include a power supply unit that supplies power to the moving unit. In the third aspect of the present invention, a stage device is provided. The stage device may include moving objects. The stage device may include a drive device as described above for moving a moving object. In the fourth aspect of the present invention, a robot device is provided. The robot device may include the drive device as described above. The robot device may include a first arm and a second arm that are relatively moved by a drive device.

The multi-rotation information detection unit 3 is a magnetic detection unit in the above embodiment, but may be an optical detection unit (eg, reflected light or transmitted light). In this case, a part of the multi-rotation information detection unit 3 may be shared with the angle detection unit 4. Further, for example, the multi-rotation information detection unit 3 is an optical detection unit, and the light emission timing of the light source (eg, the irradiation timing of the light emitted to detect the multi-rotation information) is output from the signal generation unit 5. when controlled by a pulse-like electric signal (detection signal), position置検out unit 1 (e.g., multiple rotation information detection unit 3) as described above period during operation includes a time period for emitting light by electrical signals. Further, the power supply unit 2 may use the power of the detection signal generated by the signal generation unit 5 as the power source. For example, the power supply unit 2 may not include the battery 33, and may adjust the voltage of the detection signal to a predetermined voltage by a regulator or the like and supply the power of the detection signal to the position detection unit 1. Further, in the above-described embodiment, the signal generation unit 5 generates a detection signal when the magnet 11 has a predetermined positional relationship. The encoder device EC (multi-rotation information detection unit 3) may include a signal generation unit 5 as a sensor for detecting the position information of the rotation axis SF (magnet 11).

Claims (1)

A position detection unit that detects the position information of the moving unit, and
A signal generating unit that generates a detection signal due to a change in the magnetic field accompanying the movement of the moving unit,
In a state where the power supply from the first power supply is cut off, the power supply unit that supplies power to the position detection unit and the power supply unit.
An encoder device including a cutoff unit that cuts off the supply of electric power from the power supply unit to the position detection unit based on a trigger signal indicating the end of the operation of the position detection unit.

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