KR102481561B1 - Encoder and method of calculating rotational angle position - Google Patents

Abstract

(Problem) To provide an encoder that reduces an error of a detected rotation angle position.
(Solution) The signal processing unit of the encoder unit includes a rotation angle position calculation unit 110, a correction amount table 120, and a correction unit 130. The rotation angle position calculation unit 110 detects the rotation angle position from the signal of the detection element. The correction amount table 120 stores a correction amount for eliminating an error superimposed on the signal of the detection element in proportion to the rotational speed corresponding to the divided angle positions divided during one rotation at a specific rotational speed. The correcting unit 130 calculates the speed ratio between the rotational speed in the use state and the specific rotational speed, and from the correction amount stored in the correction amount table 120, the calculated speed ratio and the correction values corresponding to the division angle positions are calculated. yield

Description

Encoder and rotation angle position calculation method {ENCODER AND METHOD OF CALCULATING ROTATIONAL ANGLE POSITION}

The present invention relates to an encoder and a rotation angle position calculation method.

BACKGROUND Conventionally, a device called a magnetic or optical encoder (rotary encoder) capable of detecting the rotational angular position of a shaft of a motor or the like as rotational angular position data exists.

In addition, encoders exist that can convert absolute value rotational angle position data into incremental signals or the like and transmit them using two transmission lines called A and B phases.

Here, in Patent Document 1, a magnetic field generating means for generating a magnetic field, a base that rotates relative to the magnetic field generating means in accordance with the rotation of the detection object, and a base provided on the base, and a relative relationship between the magnetic field generating means and the base A magnetic detection element for outputting an output signal corresponding to a magnetic field changed by rotation, and a wiring portion connected to the magnetic detection element and extending in a rotational axis direction on a virtual plane substantially perpendicular to a sensitivity direction of the magnetic detection element, the magnetic detection element comprising: A technique of an encoder is described comprising a set of wires for transmitting an output signal of an element and a control means for detecting a rotational angle of a detection target based on the phase of an output signal of a magnetic detection element.

Japanese Unexamined Patent Publication No. 2007-218592

Here, in the case of an encoder using a magnet, when the magnet rotates near the substrate, a voltage is induced in the wiring pattern.

However, in a configuration such as the device described in Patent Literature 1, the noise when this induced voltage (hereinafter referred to as induced voltage) is superimposed on the output of the magnetic sensor cannot be sufficiently reduced, and the accuracy of rotation angle position detection There was a problem that was lowered.

The present invention has been made in view of such a situation, and an object of the present invention is to provide an encoder that sufficiently reduces noise and increases the accuracy of detecting the rotation angle position even when the dielectric electromotive force changes with the rotation speed.

The encoder of the present invention is an encoder equipped with a rotational angle position calculation means for detecting a rotational angle position from a signal of a detection element, and a correction amount for eliminating an error superimposed on the signal of the detection element in proportion to a rotational speed is set to a specific rotational speed. From the correction amount table stored corresponding to the division angle positions divided during one rotation in speed, the speed ratio between the rotational speed in use and the specific rotational speed calculated, and the correction amount stored in the correction amount table, Compensation means for calculating a correction value corresponding to the calculated speed ratio and the division angle position, and correcting the rotation angle position detected by the rotation angle position calculation means by the correction value.

By configuring in this way, it is possible to correct the error overlapping in proportion to the rotational speed by converting it according to the rotational speed in use, and the rotational angle position can be detected with good precision.

In the encoder of the present invention, the detection element includes a movable object having a magnet in which a pair of magnetic poles of S and N poles are magnetized, and a stationary body on which a magnetically sensitive sensor facing the magnet is mounted. And, the error superimposed on the signal of the detection element in proportion to the rotational speed is an induced voltage induced in the stationary body by rotation of the magnet.

With this configuration, since the induced voltage is generated in proportion to the rotational speed, by calculating the speed ratio between the rotational speed in use and the specific rotational speed, and converting the correction value from the correction amount table according to the speed ratio, an appropriate correction can be made.

In the encoder of the present invention, the correction means, when calculating the speed ratio of the rotation speed in the use state and the specific rotation speed, the specific rotation speed is the relationship of the following formula (1),

ω = D/T/R × 60 … … Equation (1)

where ω is a specific rotational speed (rpm), R is an angular resolution, T is a sampling period (seconds), D is a specific angular displacement value,

The rotation speed in the use state is calculated by the following formula (2),

ω' = (D'/D) × ω... … Equation (2)

Here, ω' is the rotational speed (rpm) in the use state, and D' is a division angular difference value that is the difference between the angular displacement value at the current sampling time and the angular displacement value at the previous sampling time. characterized by

By configuring in this way, since the rotational speed is obtained only by calculating the division angle difference value between one sampling period, the amount of correction in the rotational speed to be used can be easily calculated.

The encoder of the present invention is characterized in that the correcting unit corrects the rotational angle position in the entire range of the rotational speed in the use condition.

With this configuration, since it is not necessary to divide the presence or absence of correction by the rotational speed, the correction can be easily performed.

In the encoder of the present invention, in the detection element, the potato sensor includes an A-phase sensor and a B-phase sensor corresponding to the displacement of the movable object to be detected, and a sinusoidal A-phase signal is output from the A-phase sensor. A phase B signal of a sine wave form is output from the B phase sensor, a phase difference between the A phase signal and the B phase signal is approximately π/2, and the rotation angle position calculation unit calculates the A phase signal and the B phase signal. By calculating and analyzing a Lissajous waveform on the XY plane from the phase signal, the angular position of the movable object to be detected is detected, the rotational angular position is calculated from the detected angular position, and the correction amount table is calculated based on the A phase signal and the above A correction amount is stored for each of the B-phase signals, and the correction means determines the correction amount for each of the A-phase signal and B-phase signal from the respective correction amounts of the A-phase signal and the B-phase signal in the correction amount table. It is characterized in that the correction value is calculated and corrected.

With this configuration, since there are correction tables for both the A-phase signal and the B-phase signal, even if the overlapping errors in proportion to the rotational speed differ between the A-phase signal and the B-phase signal, each optimum correction value can be obtained. and can detect the rotation angle position with good accuracy.

The encoder of the present invention, the fixed body has a double-sided substrate on which the magnetic sensor is mounted on one side and the semiconductor device is mounted on the other side, and the semiconductor device is an amplifier for amplifying the output signal from the magnetic sensor. A portion is provided, and the magnetic sensor and the semiconductor device are disposed at a position where at least a part overlaps with each other in the thickness direction of the double-sided board, and the magnetic sensor and the semiconductor device are disposed in the double-sided board. It is characterized by being electrically connected to at least one side of the semiconductor device through a plurality of through holes formed at overlapping positions in the thickness direction of the double-sided substrate.

If configured in this way, since the through hole is formed at a position overlapping at least one of the magnetic sensor and the semiconductor device, the transmission path of the output from the magnetic sensor is shortened, and the induction generated in the transmission path of the output from the sensor is inductive. Noise due to voltage is reduced, and the influence of noise caused by induced voltage can be alleviated.

The encoder of the present invention, in the potato sensor, the potato sensor-side first wiring between the potato sensor-side chip and the first output terminal on which the potato film is formed and the potato sensor-side second between the potato sensor-side chip and the second output terminal A first induced voltage generated by linkage between wires and the magnetic flux of the magnet, among a plurality of through holes, a first through hole corresponding to a first output terminal and a second through hole corresponding to a second output terminal are magnetic flux of the magnet a second induced voltage generated by linking with and, in the semiconductor device, an amplifier side first wiring between an amplifier side chip on which the amplifier unit is formed and a first input terminal electrically connected to the first output terminal, and the amplifier side The third induced voltage generated when the second wiring on the amplifier side between the chip and the second input terminal electrically connected to the second output terminal is linked with the magnetic flux of the magnet is the induced voltage of one induced voltage and the other two induced voltages. It is characterized in that it is formed so that it disappears.

By configuring in this way, the induced voltages can be offset with each other, and the influence of noise caused by the induced voltage can be alleviated.

In the encoder of the present invention, the correction means, when the sampling period is changed, calculates a period adjustment value corresponding to the sampling period of the specific rotational speed and the changed sampling period, and calculates a correction value by applying the period adjustment value. characterized by

With this configuration, even if it is necessary to change the sampling cycle, the rotation angle position can be corrected using the correction table.

A rotation angle position calculation method of the present invention is a rotation angle position calculation method executed by an encoder that detects a rotation angle position from a signal of a detection element, and a correction amount that eliminates an error superimposed on the signal of the detection element in proportion to a rotation speed. is stored in a correction amount table corresponding to a specific rotational speed and division angle positions divided in one rotation, a speed ratio between the rotational speed in use and the specific rotational speed is calculated, and the correction amount stored in the correction amount table is calculated. From the correction amount, a correction value corresponding to the calculated speed ratio and the division angle position is calculated, the signal of the detection element is corrected by the correction value, and the rotation angle position is calculated by the corrected signal of the detection element. It is characterized by doing.

By configuring in this way, it is possible to correct the error overlapping in proportion to the rotational speed by converting it according to the rotational speed in use, and the rotational angle position can be detected with good accuracy.

In the rotation angle position calculation method of the present invention, the specific rotation speed is a relationship of the following formula (1),

ω = D/T/R × 60 … … Equation (1)

where ω is a specific rotational speed (rpm), R is an angular resolution, T is a sampling period (seconds), D is a specific angular displacement value,

The rotational speed in the above use state is represented by the following formula (2),

ω' = (D'/D) × ω... … Equation (2)

Here, ω' is the rotational speed (rpm) in the use state, D' is a division angular difference value that is the difference between the angular displacement value at the current sampling time and the angular displacement value at the previous sampling time, ,

It is characterized in that the speed ratio between the rotational speed in the use state and the specific rotational speed is calculated as a value of (D'/D).

By configuring in this way, since the rotational speed is obtained only by calculating the division angle difference value between one sampling period, the amount of correction in the rotational speed to be used can be easily calculated.

In the rotation angle position calculation method of the present invention, the detection element includes a moving object having a magnet in which a pair of magnetic poles of the S pole and the N pole are magnetized, and a fixed body in which a magnetic sensor facing the magnet is mounted. Including, wherein the magnetic sensor comprises an A-phase sensor and a B-phase sensor corresponding to the displacement of the movable object to be detected, and a sinusoidal phase A signal is output from the A-phase sensor, and a sinusoidal wave is output from the B-phase sensor. A phase B signal is output, a phase difference between the phase A signal and the phase B signal is approximately π/2, and the correction amount table stores correction amounts for each of the phase A signal and the phase B signal; The angular position of the movable object to be detected is detected by calculating and analyzing a Lissajous waveform on the XY plane from the A-phase signal and the B-phase signal, the rotation angular position is calculated by the detected angular position, and the correction amount table It is characterized in that the correction value is calculated and corrected for each of the phase A signal and the phase B signal from the respective correction amounts of the phase A signal and the phase B signal.

With this configuration, since there are correction tables for both the A-phase signal and the B-phase signal, even if the overlapping errors in proportion to the rotational speed differ between the A-phase signal and the B-phase signal, each optimum correction value can be obtained. and can detect the rotation angle position with good accuracy.

In the rotation angle position calculation method of the present invention, when the sampling period is changed, a period adjustment value corresponding to the sampling period of the specific rotation speed and the changed sampling period is calculated, and a correction value is calculated by applying the period adjustment value. It is characterized by doing.

With this configuration, even if it is necessary to change the sampling cycle, the rotation angle position can be corrected using the correction table.

According to the present invention, it is possible to provide an encoder that corrects an error due to an induced voltage overlapping in proportion to a rotational speed and increases the accuracy of calculating rotation angle position.

1 is a system configuration diagram of a control system related to an embodiment of the present invention.
Fig. 2 is a diagram showing the configuration of an encoder related to an embodiment of the present invention.
Fig. 3 is a diagram showing the electrical configuration of an encoder related to an embodiment of the present invention.
4A is a diagram showing a detection principle of an encoder related to an embodiment of the present invention.
Fig. 4B is a diagram showing a detection principle of an encoder related to an embodiment of the present invention.
4C is a diagram showing the detection principle of an encoder related to an embodiment of the present invention.
Fig. 4d is a diagram showing a detection principle of an encoder related to an embodiment of the present invention.
5A is a diagram of a signal path from a magnetic sensor of an encoder to an amplifier unit according to an embodiment of the present invention.
5B is a diagram of a signal path from a potato sensor to an amplifier section of an encoder related to an embodiment of the present invention.
Fig. 6 is a diagram showing a configuration for eliminating the induced voltage of the encoder according to the embodiment of the present invention.
Fig. 7A is a block diagram showing the control structure of the signal processing unit and the structure of the correction amount table according to the embodiment of the present invention.
Fig. 7B is a block diagram showing the control structure of the signal processing unit and the structure of the correction amount table according to the embodiment of the present invention.
8 is a flowchart of rotational angle position detection processing according to an embodiment of the present invention.
9A is a graph showing the results of a comparative example of the present invention.
9B is a graph showing the results of an embodiment of the present invention.

<Embodiment>

Referring to Fig. 1, the configuration of a control system X according to an embodiment of the present invention will be described. The control system X includes an encoder unit 10, a motor 11, a control device 12, and a host device 13.

Of these, the encoder unit 10 and the control device 12 function as the encoder device 1 of the present embodiment.

The encoder unit 10 is an encoder capable of detecting a rotational angular position.

The encoder unit 10 always detects the angle of the rotating body 2 including the shaft and the like coaxial with the motor 11 as rotation angle position data. For this reason, the encoder unit 10 is provided with a fixed body 3 fixed to the frame of the motor 11 or the like.

This rotation angle position data includes multi-rotation data indicating the number of rotations of the rotating body 2 and data within one rotation indicating the angle of the rotating body 2 . Further, the rotation angle position data is data in which multi-rotation data and data within one rotation are consecutive bit strings. Among these, multi-turn data has a resolution of several bits to several tens of bits, and data within one rotation has a resolution of several bits to hundreds of bits.

Further, the encoder unit 10 outputs rotation angle position data to the control device 12 according to instructions from the control device 12 .

The detailed configuration of the encoder unit 10 will be described later.

The control device 12 controls driving of the motor 11 according to a control signal from the host device 13 . In addition, the control device 12 obtains rotation angle position data from the encoder unit 10 according to a control signal from the host device 13, for example, and transmits it to the host device 13.

The control device 12 includes, for example, a microcontroller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), and the like.

The motor 11 rotates the rotating body 2 around the central axis of rotation L in response to a control signal from the control device 12 .

The motor 11 is a general servo motor or the like provided with a rotor, a bearing, a stator, a bracket or the like.

The host device 13 is a device that controls the motor 11 . The host device 13 acquires the detected rotation angle position data and transmits a control signal corresponding to the acquired rotation angle position data to the control device 12 . In addition, the host device 13 is, for example, a logic board or the like of various devices equipped with a microcontroller.

In addition, the upper-level device 13, for example, transmits the incremental signal at the edge of the HL (H indicates a high level signal and L indicates a low level signal) of signals out of phase by 90 degrees, respectively. It is composed of two transmission lines on phase A and phase B to transmit.

[Configuration of Encoder Unit 10]

Next, with reference to Figs. 2 to 6, the overall arrangement of the encoder section 10 (rotary encoder) according to the embodiment of the present invention will be described.

The encoder unit 10 shown in FIG. 2 is a magnetic sensor device that magnetically detects the rotation around the axis (around the central axis of rotation L) of the rotating body 2 with respect to the fixed body 3 (FIG. 1). to be. 3 is an explanatory diagram showing the electrical configuration of a magnetic sensor device according to an embodiment of the present invention.

The rotary body 2 is used in a state connected to the rotary output shaft of the motor 11 or the like. On the side of the rotating body 2, a magnet 20 (moving object to be detected) directs the magnetizing surface 21 in which the N pole and the S pole are magnetized one by one in the circumferential direction toward one side in the direction of the rotation center axis L. this is maintained The magnet 20 rotates around the rotation center axis L integrally with the rotating body 2.

As shown in FIG. 2 and FIG. 3, the magnetically sensitive sensor 4 and the semiconductor device 9 (amplifier IC) are provided in the stationary body 3 side.

The magnetic sensor 4 is arranged to oppose the magnetizing surface 21 of the magnet 20 on one side in the direction of the rotation center axis L, and measures the magnetic resistance by the magnetic flux of the magnet 20.

The semiconductor device 9 includes a chip 97 (amplifier side chip, semiconductor device chip) and a signal processing unit 100 .

The chip 97 includes an amplifier unit 90 (amplifier unit 90(+A)), amplifier unit 90(-A), and amplifier unit 90(+B) that amplify the output from the potato sensor 4 )), an IC having an amplifier section 90(-B)), and the like. Signals output from the amplifier section 90(+A) and the amplifier section 90(-A) become A-phase signals. Further, signals output from the amplifier section 90(+B) and the amplifier section 90(-B) become B-phase signals.

The signal processing unit 100 A/D (Analog to Digital) converts the output from the amplifier unit 90. Further, the signal processing unit 100 detects the rotational angular position, rotational speed, and the like of the rotating body 2 based on the signal after A/D conversion. Specifically, the signal processing unit 100 is a sinusoidal A-phase signal and a B-phase signal output from the potato sensor 4, the signal of the output from the 1st Hall element 61, and the 2nd Hall element 62 Based on this, signal processing such as interpolation processing and various arithmetic processing is performed. With this, the signal processing unit 100 calculates the rotation angle position of the rotating body 2 with respect to the fixed body 3 .

A detailed configuration of the signal processing unit 100 will be described later.

In addition, the signal processing unit 100 does not have to be incorporated in the semiconductor device 9 .

Further, the encoder unit 10 is provided with a first Hall element 61 and a second Hall element 62 at positions facing the magnet 20 . The first Hall element 61 and the second Hall element 62 are located at positions deviated by 90° (π/2) from the mechanical angle in the circumferential direction. Further, inside the semiconductor device 9 or outside the semiconductor device 9, an amplifier section 95 for the first Hall element 61 and an amplifier section 96 for the second Hall element 62 are provided. is formed

In addition, the stationary body 3 including the magnet 20, the magnetic sensor 4, the first Hall element 61, and the second Hall element 62 includes a detection element for detecting the rotation angle position. make up

The potato sensor 4 is configured as a chip 40 (a potato sensor side chip) that is a sensor IC of a magnetoresistive element.

Inside the chip 40, a two-phase magnetic film having a phase difference of 90° (π/2) with respect to the phases of the element substrate 45 and the magnet 20 (A-phase (SIN) magnetic film, and a B-phase (COS) magnetic film). In short, the magnetically sensitive sensor 4 includes an A-phase sensor (the magnetically sensitive film on A) and a B-phase sensor (the magnetically sensitive film on B) corresponding to the displacement of the movable to-be-detected object.

The magnetically sensitive film of the A phase is a +A phase (SIN+) magnetic film 43 and a -A phase (SIN-) magnetic film ( 41) is provided. In addition, the B-phase magnetic film has a phase difference of 180° (π), and the +B phase (COS+) magnetic film 44 and -B phase (COS-) sensing film 44 detect the movement of the rotating body 2. A subtitle 42 is provided. In short, a sinusoidal A-phase signal sin is output from the A-phase sensor, and a sinusoidal B-phase signal cos is output from the B-phase sensor. Further, the phase difference between the A-phase signal and the B-phase signal is approximately π/2.

The +A phase magnetic film 43 and the -A phase magnetic film 41 constitute a bridge circuit shown in Fig. 4A. One end of these is connected to the power supply terminal 48 (Vcc), and the other end is connected to the ground terminal 48 (GND). An output terminal 48 (+A) from which the +A phase is output is formed at a midpoint position of the magnetic film 43 of the +A phase. At the midpoint position of the magnetic film 41 of the -A phase, an output terminal 48(-A) from which the -A phase is output is formed.

In addition, the +B phase magnetic film 44 and -B phase magnetic film 42 also constitute the bridge circuit shown in FIG. 4B similarly to the +A phase magnetic film 44 and -A phase magnetic film 41. are doing One end of these is connected to the power supply terminal 48 (Vcc), and the other end is connected to the ground terminal 48 (GND). At the midpoint position of the magnetic film 44 of the +B phase, an output terminal 48 (+B) from which the +B phase is output is formed. At the midpoint position of the magnetic film 42 of the -B phase, an output terminal 48(-B) from which the -B phase is output is formed.

As shown in FIG. 2 , the magnetic sensor 4 is disposed on the central axis L of rotation of the magnet 20, and faces the magnetization boundary portion of the magnet 20 in the direction of the central axis L of rotation. there is.

For this reason, the magnetic field intensity of the magnetically sensitive films 41 to 44 of the magnetically sensitive sensor 4 changes in the in-plane direction of the magnetizing surface 21 at a magnetic field intensity equal to or higher than the saturation sensitivity range of the resistance value of each of the magnetically sensitive films 41 to 44. A rotating magnetic field can be detected. That is, at the magnetic boundary line portion, a rotating magnetic field whose direction changes in the in-plane direction is generated at a magnetic field intensity equal to or higher than the saturation sensitivity range of the resistance of each magnetic film 41 to 44 . Here, the saturation sensitivity region generally refers to a region other than a region in which the amount of change in resistance value (k) can be approximated with the magnetic field strength (H) by the expression “k ∝ H ² ”.

The principle of detecting the direction of a rotating magnetic field (rotation of a magnetic vector) with a magnetic field intensity equal to or higher than the saturation sensitivity range is to apply a magnetic field intensity that saturates the resistance value while the magnetic films 41 to 44 are energized. At this time, the relationship between the angle θ formed by the magnetic field and the current direction and the resistance value R of the magnetic films 41 to 44 is used as shown by the following formula (0):

R = R0 - k × sin2θ . … formula (0)

Here, R0 represents the resistance value in a non-magnetic field, and k represents the amount of change in resistance value (it becomes a constant when it is over the saturation sensitivity range).

When a rotating magnetic field is detected based on this principle, when the angle θ is changed, the resistance value R is changed along a sinusoidal wave. For this reason, the output of the A-phase signal and the B-phase signal output of high waveform quality can be obtained.

(Configuration of signal path from potato sensor 4 to amplifier unit 90)

With FIG. 5, the signal path from the potato sensor 4 in the encoder part 10 which concerns on embodiment of this invention to the amplifier part 90 is demonstrated.

5A and 5B are explanatory diagrams showing a mounting structure of a magnetic sensor 4 and a semiconductor device 9 on a double-sided board 5 (circuit board), and a wiring pattern of the double-sided board 5 (circuit board) It is an explanatory diagram showing the etc. 5B shows only the wiring patterns according to the present embodiment among the wiring patterns. In Fig. 5B, a wiring pattern formed on one side 501 of the double-sided board 5 is indicated by a solid line, and a wiring pattern formed on the other side 502 of the double-sided board 5 is indicated by a dotted line. In addition, FIG. 5B shows the magnetic sensor 4 by the dotted line, and the semiconductor device 9 is shown by the chain dotted line.

3 and 5A, in the encoder part 10 of this embodiment, the potato sensor 4 is a chip 40 and a plurality of output terminals 48 electrically connected to the chip 40 (+A), 48(-A), 48(+B), 48(-B)).

The chip 40 and the output terminals 48(+A), 48(-A), 48(+B), 48(-B)) are wired to the magnetic sensor side (47(+A), 47(-A) ), 47(+B), 47(-B)) are electrically connected.

In the magnetic sensor 4, the "first output terminal", "second output terminal", "potential sensor side first wiring" and "potential sensor side second wiring" in the present embodiment correspond as follows. .

A common (phase use):

1st output terminal of potato sensor 4 = output terminal 48(+A)

2nd output terminal of potato sensor (4) = output terminal (48(-A))

1st wiring on the potato sensor side = wiring on the potato sensor side (47(+A))

2nd wiring on the potato sensor side = wiring on the potato sensor side (47(-A))

B Common:

1st output terminal of potato sensor 4 = output terminal (48(+B))

2nd output terminal of potato sensor (4) = output terminal (48(-B))

1st wiring on the potato sensor side = wiring on the potato sensor side (47(+B))

2nd wiring on the potato sensor side = wiring on the potato sensor side (47(-B))

In addition, the semiconductor device 9 includes a chip 97 including an amplifier unit 90 (amplifier units 90(+A), 90(-A), 90(+B), 90(-B)) and a plurality of input terminals 98(+A), 98(-A), 98(+B), 98(-B) electrically connected to the chip 97. The chip 97 and the input terminals 98(+A), 98(-A), 98(+B), 98(-B) are connected to the amplifier side wiring 93(+A), 93(-A), 93(+B), 93(-B)) are electrically connected.

In the semiconductor device 9, the "first input terminal", "second input terminal", "amplifier side first wiring" and "amplifier side second wiring" in the present embodiment correspond as follows.

A commercial:

1st input terminal of semiconductor device 9 = input terminal 98(+A)

Second input terminal of semiconductor device 9 = input terminal 98(-A)

Amplifier-side wiring 1 = Amplifier-side wiring (93(+A))

2nd wiring on the amplifier side = wiring on the amplifier side (93(-A))

B Common:

1st input terminal of semiconductor device 9 = input terminal 98(+B)

Second input terminal of semiconductor device 9 = input terminal 98(-B)

Amplifier-side wiring 1 = Amplifier-side wiring (93(+B))

2nd wiring on the amplifier side = wiring on the amplifier side (93(-B))

In this embodiment, in electrically connecting the magnetic sensor 4 and the semiconductor device 9, the double-sided board|substrate 5 is used. In the double-sided board 5, wiring is formed of copper foil or the like on both sides of a main body of a board such as a phenol board or a glass-epoxy board, and each part is mounted.

Specifically, the magnetic sensor 4 is mounted on one side 501 side of the double-sided substrate 5, and the semiconductor device 9 is mounted on the other side 502 side. The double-sided substrate 5 has its thickness direction (direction indicated by arrow T) directed toward the direction of the rotation center axis L of the magnet 20 .

The magnetic sensor 4 and the semiconductor device 9 are arrange|positioned at the position where at least one part mutually overlaps in the thickness direction of the double-sided board|substrate 5. Moreover, the magnetic sensor 4 and the semiconductor device 9 are arrange|positioned so that one may be located inside the area|region which parallel-projected to the thickness direction of the double-sided board|substrate 5. In this embodiment, the plane size of the semiconductor device 9 is larger than the plane size of the magnetic sensor 4. Moreover, the magnetic sensor 4 is arrange|positioned so that it may be located inside the area|region which parallel-projected the semiconductor device 9 to the thickness direction of the double-sided board|substrate 5. The double-sided board 5 is arranged so that the center of the magnetic sensor 4 (chip 40) and the center of the semiconductor device 9 (chip 97) are located on the rotation center axis L.

Moreover, the plane size of the magnetic sensor 4 may be larger than the plane size of the semiconductor device 9. In this case, the semiconductor device 9 is arrange|positioned inside the area|region which parallel-projected the magnetic sensor 4 to the thickness direction of the double-sided board|substrate 5.

Moreover, in the encoder part 10, the potato sensor 4 and the semiconductor device 9 are electrically connected via the some through-hole 50 formed in the double-sided board|substrate 5. Moreover, the some through hole 50 is formed in the overlapping position in the thickness direction of at least one of the magnetic sensor 4 and the semiconductor device 9 and the double-sided board|substrate 5.

In this embodiment, the some through hole 50 is formed in the overlapping position in the thickness direction of the magnetic sensor 4 and the double-sided board|substrate 5. For this reason, the some through-hole 50 is formed in the position overlapping in the thickness direction of both the magnetic sensor 4 and the semiconductor device 9 and the double-sided board|substrate 5.

(Detailed configuration of the double-sided board 5)

Hereinafter, lands, wirings, and the like of the double-sided board 5 will be described with reference to FIGS. 3 and 5A and 5B. The double-sided board 5 has a plurality of lands 51 on which the magnetic sensor 4 is mounted, and a plurality of wirings 52 extending from the lands 51 are formed on one side 501 . In addition, a through hole 50 is formed at the tip of each of the plurality of wirings 52 .

In this embodiment, the plurality of lands 51 include a land 51 (Vcc) and a land 51 (GND). The land 51 (Vcc) is a land for power supply terminals on which the power supply terminal 48 (Vcc) of the magnetically sensitive sensor 4 is mounted. The land 51 (GND) is a land for ground terminals on which the ground terminal 48 (GND) of the potato sensor 4 is mounted.

Further, the plurality of lands 51 include land 51(+A), land 51(-A), land 51(+B), and land 51(-B). has been

The land 51 (+A) is a +A commercial land on which the output terminal 48 (+A) of the potato sensor 4 is mounted. Land 51 (-A) is -A commercial land on which the output terminal 48 (-A) of the potato sensor 4 is mounted. The land 51 (+B) is a +B commercial land on which the output terminal 48 (+B) of the potato sensor 4 is mounted. Land 51 (-B) is a -B commercial land on which the output terminal 48 (-B) of the potato sensor 4 is mounted.

The plurality of wirings 52 include a wiring 52 (Vcc) and a wiring 52 (GND). Wiring 52 (Vcc) is wiring for power supply terminals to which power supply terminal 48 (Vcc) of the magnetic sensor 4 is electrically connected. The wiring 52 (GND) is a wiring for ground terminals to which the ground terminal 48 (GND) of the potato sensor 4 is electrically connected.

Further, the plurality of wirings 52 include wiring 52(+A), wiring 52(-A), wiring 52(+B), and wiring 52(-B). has been Wiring 52 (+A) is +A commercial wiring to which output terminal 48 (+A) of potato sensor 4 is electrically connected. The wiring 52 (-A) is -A commercial wiring to which the output terminal 48 (-A) of the potato sensor 4 is electrically connected. The wiring 52 (+B) is a +B commercial wiring to which the output terminal 48 (+B) of the potato sensor 4 is electrically connected. Wiring 52 (-B) is -B commercial wiring to which output terminal 48 (-B) of the magnetic sensor 4 is electrically connected.

The plurality of through holes 50 include a through hole 50 (Vcc) and a through hole 50 (GND). The through hole 50 (Vcc) is a through hole for power supply terminals to which the power supply terminal 48 (Vcc) of the potato sensor 4 is electrically connected. The through hole 50 (GND) is a through hole for ground terminals to which the ground terminal 48 (GND) of the potato sensor 4 is electrically connected.

Further, in the plurality of through holes 50, through holes 50(+A), through holes 50(-A), through holes 50(+B), and through holes 50(- B)) is included. Through-hole 50 (+A) is +A common through-hole to which output terminal 48 (+A) of potato sensor 4 is electrically connected. Through-hole 50 (-A) is -A common through-hole to which output terminal 48 (-A) of potato sensor 4 is electrically connected. Through-hole 50 (+B) is +B common through-hole to which output terminal 48 (+B) of potato sensor 4 is electrically connected. Through-hole 50 (-B) is -B common through-hole to which output terminal 48 (-B) of potato sensor 4 is electrically connected.

Further, on the other side 502 of the double-sided substrate 5, a plurality of lands 53 on which the semiconductor device 9 is mounted, and a plurality of wires 54 extending from the lands 53 are formed. The tips of the plurality of wires 54 overlap each of the tips of the plurality of wires 52 in a one-to-one relationship. A through hole 50 is formed in this overlapping portion.

In the plurality of lands 53, +A commercial land 53(+A), -A commercial land 53(-A), +B commercial land 53(+B), and -B commercial land Land (53(-B)) is included. The +A commercial land 53(+A) corresponds to the output terminal 48(+A) of the potato sensor 4. -A commercial land 53 (-A) corresponds to the output terminal 48 (-A) of the potato sensor 4. The +B commercial land 53 (+B) corresponds to the output terminal 48 (+B) of the potato sensor 4. -B commercial land 53 (-B) corresponds to the output terminal 48 (-B) of the potato sensor 4.

Further, among the lands 53, an input terminal 98(+A) electrically connected to the amplifier unit 90(+A) of the semiconductor device 9 is mounted on the land 53(+A). there is. In addition, an input terminal 98 (-A) electrically connected to the amplifier section 90 (-A) of the semiconductor device 9 is mounted on the land 53 (-A). In addition, an input terminal 98 (+B) electrically connected to the amplifier section 90 (+B) of the semiconductor device 9 is mounted on the land 53 (+B). In addition, an input terminal 98 ( -B) electrically connected to the amplifier section 90 ( -B) of the semiconductor device 9 is mounted on the land 53 ( -B).

The plurality of wirings 54 include wiring 54(+A), wiring 54(-A), wiring 54(+B), and wiring 54(-B). . The wiring 54 (+A) is a +A commercial wiring corresponding to the output terminal 48 (+A) of the potato sensor 4. Wiring 54 (-A) is -A commercial wiring corresponding to the output terminal 48 (-A) of the potato sensor 4. The wiring 54 (+B) is a +B commercial wiring corresponding to the output terminal 48 (+B) of the potato sensor 4 . Wiring 54 (-B) is a -B commercial wiring corresponding to output terminal 48 (-B) of potato sensor 4.

Further, in the wiring 54, a through hole 50(+A) is formed in the overlapped portion of the wiring 54(+A) and the wiring 52(+A). Further, a through hole 50(-A) is formed in the overlapped portion of the wiring 54(-A) and the wiring 52(-A). Further, a through hole 50(+B) is formed in the overlapped portion of the wiring 54(+B) and the wiring 52(+B). Further, a through hole 50(-B) is formed in the overlapped portion of the wiring 54(-B) and the wiring 52(-B).

Further, on the other side 502 of the double-sided board 5, the land 55 (Vcc) and the land 55 (GND) are spaced apart from the other land 53 to form a through hole 50 (Vcc) and a through hole 50 (Vcc). It is formed only at the position overlapping the hole 50 (GND). The land 55 (Vcc) is a land to which the power supply terminal 48 (Vcc) of the magnetically sensitive sensor 4 is connected. The land 55 (GND) is a land to which the ground terminal 48 (GND) of the potato sensor 4 is connected.

In the encoder unit 10, the "first land for magnetic sensors" and the "second land for magnetic sensors" in the present embodiment correspond as follows.

A commercial:

1st land for potato sensor = land (51(+A))

2nd Land for Potential Sensor = Land (51(-A))

B Common:

1st land for potato sensor = land (51(+B))

2nd Land for Potential Sensor = Land (51(-B))

In addition, the "first through hole" and the "second through hole" in the present embodiment correspond as follows.

A commercial:

1st through hole = through hole (50(+A))

2nd through hole = through hole (50(-A))

B Common:

1st through hole = through hole (50(+B))

2nd through hole = through hole (50(-B))

In addition, the "first land for semiconductor devices" and the "second land for semiconductor devices" in the present embodiment correspond as follows.

A commercial:

1st land for semiconductor device = land (53(+A))

2nd land for semiconductor device = land (53(-A))

B Common:

1st land for semiconductor device = land (53(+B))

2nd land for semiconductor device = land (53(-B))

(Measures against induced voltage in phase A)

Next, with reference to Fig. 6, a configuration for effectively canceling an induced voltage by a circuit in phase A of the encoder unit 10 according to the embodiment of the present invention will be described.

First, in the double-sided substrate 5 used for the encoder unit 10, a first land for a magnetic sensor (land 51(+A)) and a second land for a magnetic sensor (land 51(-A)) ), the extension direction of the imaginary line connecting them will be described. Here, the first land (land 51 (+A)) for the sensor is electrically connected to the first output terminal (output terminal 48 (+A)) of the sensor 4 on one side (501). connected to The second land (land (51(-A))) for the magnetic sensor is paired with the first output terminal (output terminal (48(+A))) of the magnetic sensor (4) on the one side (501) side. The second output terminal (output terminal 48(-A)) formed is electrically connected.

In this direction, with respect to the first land (land 53(+A)) for the semiconductor device electrically connected to the first land (land 51(+A)) for the magnetic sensor on the other side 502 side. The direction in which the second land for the semiconductor device (land 53(-A)) electrically connected to the second land for the magnetic sensor (land 51(-A)) on the other side 502 is located is It is opposite to the direction in which the second land (land 51(-A)) for the sensor is located with respect to the first land (land 51(+A)) for the sensor.

More specifically, on the other side 502 of the double-sided board 5, the +A commercial wiring 54(+A) is connected from the through hole 50(+A) to the through hole 50(-A). It extends to the side where it is located. Further, the -A commercial wiring 54(-A) extends from the through hole 50(-A) to the side where the through hole 50(+A) is located. For this reason, in A phase, the first land (land 51 (+A)) for the magnetic sensor of the magnetic sensor 4 and the second land (land 51 (-) for the magnetic sensor of the magnetic sensor 4) In the direction in which the imaginary line connecting A))) extends, the second land (land 53(-A)) for the semiconductor device is relative to the first land (land 53(+A)) for the semiconductor device. The direction in which is located is opposite to the direction in which the second land (land 51 (-A)) for the potato sensor is located with respect to the first land (land (51 (+A))) for the potato sensor. That is, a transmission path from the first land (land 51 (+A)) for the magnetic sensor to the first land (land (53 (+A))) for the semiconductor device, and the second land (land (51 The transmission path from (-A))) to the second land (land 53 (-A)) for semiconductor devices is switched midway.

Here, in the present embodiment, when the magnet 20 rotates, the following first induced voltage, second induced voltage, and third induced voltage are mainly generated. The 1st induced voltage is the wiring 47(+A), 47(-A) between the chip 40 and the output terminal 48(+A), 48(-A) in the potato sensor 4 It is an induced voltage generated by linkage with the magnetic flux of the magnet 20. The second induced voltage is an induced voltage generated when the through holes 50 (+A) and 50 (-A) interlink with the magnetic flux of the magnet 20 . The third induced voltage is applied to the wiring 93(+A) between the chip 97 of the semiconductor device 9 and the input terminal 98(+A) and the input terminal 98(-A), and the wiring ( 93(-A)) is an induced voltage generated by linkage with the magnetic flux of the magnet 20.

However, these first induced voltages, the second induced voltages, and the third induced voltages have no one induced voltage and two other induced voltages due to the above-described configuration. In short, in the present embodiment, the transmission path from the first land (land 51 (+A)) for the magnetic sensor to the first land (land (53 (+A))) for the semiconductor device, and the second land for the magnetic sensor The position of the transmission path from the land (land 51(-A)) to the second land (land 53(-A)) for semiconductor devices is switched on the other side 502 of the double-sided substrate 5. Therefore, the third induced voltage can be canceled by the first induced voltage and the second induced voltage.

In addition, when viewed from the direction of the rotational center axis L, a virtual connection between the first land (land 53(+A)) for the semiconductor device and the second land (land 53(-A)) for the semiconductor device is provided. A line, a virtual line connecting the first through hole (through hole (50 (+A))) and the second through hole (through hole (50 (-A))), and the first land (land (51 (+A))) and at least two virtual lines among the virtual lines which connect the 2nd land (land 51(-A)) for magnetic sensors are extended in parallel. Therefore, the phases of at least two of the first induced voltage, the second induced voltage, and the third induced voltage can be matched. Therefore, it is suitable for mutually canceling induced voltages.

In this embodiment, the third induced voltage is canceled by the first induced voltage and the second induced voltage. Therefore, with respect to a virtual line connecting the first land (land 53(+A)) for semiconductor devices and the second land (land 53(-A)) for semiconductor devices, the first through hole (through hole) A virtual line connecting the hole (50(+A))) and the second through hole (through hole (50(-A))), and the first land (land (51(+A))) for the demagnetizing sensor and the demagnetizing line At least one virtual line among the virtual lines connecting the 2nd land for a sensor (land 51(-A)) extends in parallel. More specifically, on phase A, a virtual line connecting the first land for semiconductor devices (land 53(+A)) and the second land for semiconductor devices (land 53(-A)), and the first through An imaginary line connecting the hole (through hole 50(+A)) and the second through hole (through hole 50(-A)) extends in parallel. For this reason, since the phases of the second induced voltage and the third induced voltage can be matched, the third induced voltage can be reduced by the second induced voltage. In addition, a virtual line connecting the first land (land 51 (+A)) for the potato sensor and the second land (land (51 (-A))) for the potato sensor is inclined in an oblique direction with respect to the virtual line. has been extended However, the inclination is less than 30°. Accordingly, since the phases of the first induced voltage and the third induced voltage can be brought closer, the third induced voltage can be reduced by the first induced voltage.

In particular, in this embodiment, as shown in Fig. 6, the cross-sectional area of each loop is proportional to the magnitude of the induced voltage. Thereby, the distance between the through hole 50 (+A) and the through hole 50 (-A) is optimized, and in the magnetic sensor 4, the chip 40 and the output terminal 48 (+A), The sum of the area S4A partitioned by 48(-A)) and the area S50A partitioned by through holes 50(+A) and 50(-A) is the amplifier unit of semiconductor device 9 It is set equal to the area S9A partitioned by the chip 97 of (90(+A), 90(-A)) and the input terminals 98(+A), 98(-A). For this reason, the third induced voltage can be canceled by the first induced voltage and the second induced voltage by switching the transmission path midway. Therefore, generation of inductive noise can be suppressed.

(Measures against induced voltage in phase B)

In addition, regarding the B phase, it has the same structure as the A phase. In the double-sided board 5, on one side 501 side, a first land (land ( 51 (+B))) and the second output terminal (output terminal (output terminal ( 48 (-B))) is electrically connected to the second land (land 51 (-B)) for the potato sensor in the direction in which the imaginary line connecting it extends, on the other side (502) side. The second land (land (land ( The direction in which the second land (land 53 (-B)) for the semiconductor device electrically connected to 51 (-B)) is located is the first land (land 51 (+B)) for the magnetic sensor. It is opposite to the direction in which the second land (land 51(-B)) for the potato sensor is located.

More specifically, on the other side 502 of the double-sided board 5, the +B commercial wiring 54(+B) is connected from the through hole 50(+B) to the through hole 50(-B). It extends to the side where it is located. In addition, the -B commercial wiring 54(-B) extends from the through hole 50(-B) to the side where the through hole 50(+B) is located. For this reason, in the B phase, the first land (land (51 (+B))) for the magnetic sensor of the magnetic sensor 4 and the second land (land (51 (-)) for the magnetic sensor of the magnetic sensor 4 In the direction in which the imaginary line connecting B))) extends, the second land (land 53(-B)) for the semiconductor device is relative to the first land (land 53(+B)) for the semiconductor device. The direction in which is located is opposite to the direction in which the second land (land 51 (-B)) for the potato sensor is located with respect to the first land (land (51 (+B))) for the potato sensor. That is, a transmission path from the first land (land 51 (+B)) for the magnetic sensor to the first land (land (53 (+B))) for the semiconductor device, and the second land (land (51 (-B))) to the second land (land 53 (-B)) for semiconductor devices, the transmission path is switched midway.

Therefore, when the magnet 20 rotates, the wire 47 (+B), 47 ( between the chip 40 and the output terminals 48 (+B), 48 (-B)) -B)) 1st induced voltage generated by linking with the magnetic flux of the magnet 20, 2nd induced voltage generated by linking the through-holes (50(+B), 50(-B)) with the magnetic flux of the magnet 20 induced voltage, and wirings 93(+B), 93(-B) between the chip 97 and the input terminals 98(+B), 98(-B) of the semiconductor device 9 are connected to the magnet 20 ), the third induced voltage generated by linking with the magnetic flux of one of the induced voltages and the other two induced voltages disappear. In the present embodiment, a transmission path from the first land (land 51 (+B)) for the magnetic sensor to the first land (land (53 (+B))) for the semiconductor device, and the second land ( Since the position of the transmission path from the land 51(-B)) to the second land (land 53(-B)) for the semiconductor device is switched on the other side 502 of the double-sided substrate 5, 3 The induced voltage can be eliminated by the first induced voltage and the second induced voltage.

In addition, when viewed from the direction of the rotation center axis L, a virtual connection between the first land (land 53(+B)) for the semiconductor device and the second land (land 53(-B)) for the semiconductor device is provided. A line, a virtual line connecting the first through hole (through hole (50 (+B))) and the second through hole (through hole (50 (-B))), and the first land (land (51 (+B))) and at least two virtual lines among the virtual lines which connect the 2nd land (land 51(-B)) for magnetic sensors are extended in parallel. Therefore, the phases of at least two of the first induced voltage, the second induced voltage, and the third induced voltage can be matched. Therefore, it is suitable for mutually canceling induced voltages.

In this embodiment, the third induced voltage is canceled by the first induced voltage and the second induced voltage. Therefore, with respect to a virtual line connecting the first land (land 53(+B)) for semiconductor devices and the second land (land 53(-B)) for semiconductor devices, the first through hole (through hole) A virtual line connecting the hole (50(+B))) and the second through hole (through hole (50(-B))), and the first land (land (51(+B))) and the demagnetizing sensor for the demagnetizing sensor. At least one virtual line among the virtual lines connecting the 2nd land for a sensor (land 51(-B)) is extended in parallel.

More specifically, on B, a virtual line connecting the first land for semiconductor devices (land 53(+B)) and the second land for semiconductor devices (land 53(-B)), and the first through An imaginary line connecting the hole (through hole 50(+B)) and the second through hole (through hole 50(-B)) extends in parallel. For this reason, since the phases of the second induced voltage and the third induced voltage can be matched, the third induced voltage can be reduced by the second induced voltage. In addition, a virtual line connecting the first land (land 51 (+A)) for the potato sensor and the second land (land (51 (-A))) for the potato sensor extends parallel to the virtual line. has been For this reason, the phase of the 1st induced voltage and the 3rd induced voltage can be made close. Therefore, the third induced voltage can be reduced by the first induced voltage.

In particular, in this embodiment, as shown in FIG. 6, since the cross-sectional area of each loop and the magnitude of the induced voltage are proportional, the spacing between the through holes 50(+B) and the through holes 50(-B) is optimized, , In the potato sensor 4, the area S4B partitioned by the chip 40 and the output terminals 48(+B) and 48(-B), and the through holes 50(+B) and 50(- B)) The sum of the areas S50B partitioned is the chip 97 and the input terminal 98 (+B) of the amplifier sections 90 (+B) and 90 (-B) of the semiconductor device 9, 98(-B)) is set equal to the area S9B. For this reason, the third induced voltage can be canceled by the first induced voltage and the second induced voltage by switching the transmission path midway. Therefore, generation of inductive noise can be suppressed.

As described above, in the encoder unit 10 of this embodiment, the magnetic sensor 4 is mounted on one side 501 side, and the double-sided board 5 on which the semiconductor device 9 is mounted on the other side 502 side ) is used, and the magnetic sensor 4 and the semiconductor device 9 are electrically connected via the through hole 50 of the double-sided board 5. For this reason, it is not necessary to secure a large space around the magnet 20. In addition, the magnetic sensor 4 and the semiconductor device 9 are arranged at a position where at least a part overlaps each other in the thickness direction of the double-sided substrate 5, and the through hole 50 is the magnetic sensor 4 and It is formed in the position overlapping with at least one side of the semiconductor device 9.

In particular, in this embodiment, the through hole 50 is formed in the position which overlaps with both the magnetic sensor 4 and the semiconductor device 9 in the thickness direction of the double-sided board|substrate 5. For this reason, the transmission path|route from the magnetically sensitive sensor 4 to the semiconductor device 9 becomes short, and a magnetic flux and the area which crosslinks become narrow. Therefore, the induced voltage which arises in the transmission path of the output from the potato sensor 4 becomes low. As a result, the noise by the induced voltage which arises in the transmission path of the output from the potato sensor 4 becomes small, and the influence of the noise by the induced voltage on the detection result can be alleviated.

Moreover, the magnetic sensor 4 is formed on the rotation center axis line of the magnet 20, and the double-sided board|substrate 5 directs the thickness direction to the rotation center axis direction of the magnet 20, and is arrange|positioned. For this reason, as shown in Fig. 5A, magnetic flux is formed along the double-sided board 5. Therefore, the loops of the wirings 52 and 54 formed on the double-sided board 5 are small in amount of linkage with the magnetic flux. For this reason, the induction noise which arises in the transmission path of the output from the magnetically sensitive sensor 4 becomes small.

In addition, the center of the potato sensor 4 and the center of the semiconductor device 9 are located on the rotation center axis line L. For this reason, the transmission path|route from the magnetically sensitive sensor 4 to the semiconductor device 9 can be arrange|positioned in the vicinity of the rotation center axis line L. Therefore, since the temporal change of the magnetic flux linking with the transmission route is small, the induced voltage generated in the transmission route of the output from the magnetically sensitive sensor 4 is low. Therefore, induced noise can be reduced.

In addition, in this embodiment, the position of the transmission path from the magnetic sensor 4 to the semiconductor device 9 is switched between the +A phase and the -A phase, and the transmission path from the magnetic sensor 4 to the semiconductor device 9 The position is also swapped between the +B phase and the -B phase. Therefore, the direction of the loop toward the semiconductor device 9 from the magnetic sensor 4 can be reversed only by changing the structure of the double-sided board 5. For this reason, the polarities of the induced voltages can be inverted midway to cancel each other out, and the influence of the induced noise can be alleviated.

[Configuration of Signal Processing Unit 100]

Next, with reference to FIG. 7A , the detailed configuration at the time of correcting the rotation angle position by the signal processing unit 100 will be described.

The signal processing unit 100 is a CPU, microcontroller, DSP, ASIC, or the like equipped with a recording medium such as RAM, ROM, or flash memory. The signal processing unit 100 detects the rotation angle position from the signal of the detection element.

More specifically, the signal processing unit 100 includes a rotation angle position calculation unit 110 (rotation angle position calculation means), a correction amount table 120, and a correction unit 130 (correction means).

The rotation angle position calculation unit 110 calculates the rotation angle position according to the signal of the detection element.

Specifically, the rotation angle position calculation unit 110 detects the angular position θ of the movable object to be detected by calculating and analyzing a Lissajous waveform on the XY plane from the A-phase signal and the B-phase signal. At this time, the rotation angle position calculation unit 110 determines which of the A-phase signal (sinusoidal signal sin) and the B-phase signal (sinusoidal signal cos) by the first Hall element 61 and the second Hall element 62. Calculate whether it is located in the interval. The rotation angle position calculation unit 110 calculates the rotation angle position from the angular position θ of the movable to-be-detected object and this section. This rotation angle position is an absolute value (absolute value), and is an integer value representing a value obtained by decomposing one circumference by an angular resolution (R) as a unit. The value of this angular resolution R is 2^20 = 1048576 when a detection element with a resolution of 20 bits is used. In addition, for this integer value, you may use 2's complement in which the code is included for 1 bit.

Further, the rotation angle position calculation unit 110 calculates the displacement of the rotation angle position during the sampling period T (seconds) as an angular displacement value D'. In short, the rotational angle position calculation unit 110 calculates the difference between the rotational angle position at the current sampling time and the rotational angle position at the previous sampling time as the angular displacement value D'. This angular displacement value D' becomes, for example, an integer value whose unit is a value obtained by dividing one rotation by the angular resolution R. In short, when R is 1048576, D becomes a value representing one rotation at 1048576. In addition, the sampling period T is a value such as several microseconds to hundreds of microseconds, and is variable as will be described later.

The correction amount table 120 corresponds to a division angle position obtained by dividing one rotation at a specific rotation speed ω by a specific number of divisions for eliminating an error superimposed on the signal of the detection element in proportion to the rotation speed. remember Here, the error due to the induced voltage described above increases in proportion to the rotational speed. For this reason, as described below, if the correction amount in the specific rotational speed ω is stored, the correction value can be calculated by calculating the speed ratio with the actual rotational speed. This specific rotational speed ω is higher than the usual rotational speed of the encoder section 10, and a rotational speed at which the induced electromotive force becomes large, for example, a value of several thousand rpm or more is used as a reference. Further, the correction amount table 120 includes an A-phase signal table 121 and a B-phase signal table 122 .

Details of this correction amount table 120 will be described later.

Correction unit 130 calculates a speed ratio between the rotational speed in the use state and the specific rotational speed ω. Further, the correcting unit 130 calculates the divided angular position from the current rotation angle position, and reads the correction amount at the divided angular position from the correction amount table 120 . Correction unit 130 calculates a correction value by multiplying the read correction amount by the calculated speed ratio. Correction unit 130 corrects the signal of the detection element by the correction value. In short, since the error due to the induced voltage is proportional to the rotational speed, the correcting unit 130 uses the speed ratio with the current rotational speed based on the specific rotational speed ω of several thousand rpm as a standard to obtain the actual Calculate the correction value.

In addition, the correction unit 130, when calculating the speed ratio of the rotation speed in the use state and the specific rotation speed,

The specific rotational speed (ω) (rpm) is the relationship of the following formula (1),

ω = D/T/R × 60 … … Equation (1)

Here, R is the angular resolution, T is the sampling period (seconds), and D is the specific angular displacement value.

In addition, in this specific rotational speed (omega), the rotational speed (omega') (current rotational speed) in a use state is computed by the following formula (2).

ω' = (D'/D) × ω... … Equation (2)

Here, D' is a divisional angular difference value that is the difference between the angular displacement value at the current sampling time and the angular displacement value at the previous sampling time.

Further, the correction unit 130 calculates the division angle position for the correction amount table 120 from the rotation angle position calculated by the rotation angle position calculation unit 110 . Correction unit 130 can perform this calculation at high speed by bit shifting, as will be described later.

Further, when the sampling period is changed, the correction unit 130 calculates a period adjustment value corresponding to the ratio of the sampling period T of the specific rotational speed ω and the changed sampling period T', and adjusts the period. Calculate the correction value by applying the value. In short, when the sampling period T' is equal to the sampling period T of the specific rotational speed ω, the period adjustment value becomes 1.

Further, the correction unit 130 calculates the final correction value by the following equation (3):

Correction value = correction amount × speed ratio × cycle adjustment value/(specific rounding value)… … Equation (3)

Here, the specific rounding value is a value determined by the relationship between a specific division number of one rotation at a specific rotational speed ω and the angular resolution R. For example, when the specific division number is 256 and the angular resolution (R) is 20 bits, the specific rounding value becomes 8192.

Further, the correction unit 130 corrects the signal of the detection element in the entire range of the rotation speed in the use state. Specifically, the correcting unit 130 corrects the signal from the rotational speed ω' in the above-described use state of 0 (rpm) to the upper detection limit speed. In addition, the correction unit 130 can be configured so as not to correct the signal when the rotational speed ω' is lower than a specific speed.

Further, the correction unit 130 calculates and corrects a correction value for each of the A-phase signal and B-phase signal from the respective correction amounts of the A-phase signal and B-phase signal in the correction amount table 120 . In short, the correction unit 130 calculates a correction value for the A-phase signal from the correction amount of the A-phase signal table 121 . Further, the correction unit 130 calculates a correction value from the correction amount of the B-phase signal table 122 for the B-phase signal.

(Details of correction amount table 120)

Here, with reference to Fig. 7B, details of the correction amount table 120 will be described.

As described above, the correction amount table 120 is a table in which correction amounts for eliminating errors superimposed on signals of detection elements are stored. Here, the detecting element is a fixed body 3 mounted with a movable object to be detected having a magnet 20 magnetized with a pair of magnetic poles of S and N poles, and a magnetic sensor 4 opposing the magnet 20. contains For this reason, the induced voltage induced in the stationary body 3 when the magnet 20 rotates becomes an error that is superimposed on the signal of the detection element in proportion to the rotational speed. In the A-phase signal and the B-phase signal, different values of this error overlap in relation to the shape, thickness, or arrangement error of the pattern on the double-sided substrate 5 (FIG. 3). For this reason, the correction amount table 120 is stored as the A-phase signal table 121 and the B-phase signal table 122 for the A-phase signal and the B-phase signal, respectively.

Further, in the correction amount table 120, the error value of each of the A-phase signal and the B-phase signal at a specific rotational speed ω is taken as the correction amount, and corresponding to the division angle position obtained by dividing one rotation by a specific number of divisions, remember In addition, the storage area of a storage medium can be saved by making the specific division number of this division angular position into a value smaller than the angular resolution R of Formula (1) mentioned above. For example, in the example of FIG. 7B, the specific division number is set to 256. Further, by making this specific division number a power of 2, it is possible to calculate the correction value at high speed by bit arithmetic.

In addition, the correction amount table 120 is, for example, the value of each of the A-phase signal and the B-phase signal detected in the state in which the shaft is stopped, and each of the A-phase signal and B-phase signal detected at a specific rotational speed ω It is possible to calculate by comparing the value of In the example of FIG. 7B , for each of the A-phase signal table 121 and the B-phase signal table 122, correction amount values corresponding to 0 to 255, which are division angular positions during one rotation, are stored, respectively.

[Rotation angle position detection processing]

Next, with reference to FIG. 8, the rotation angle position detection process by the encoder unit 10 according to the embodiment of the present invention will be described.

In the rotational angle position detection processing of the present embodiment, the current rotational speed is calculated, and the speed ratio between the current rotational speed and the specific rotational speed is calculated. Further, the correction amount corresponding to the divided angular position is read from the correction amount table 120 and multiplied by the calculated speed ratio to calculate a correction value. The rotation angle position is corrected by the correcting unit 130 based on this correction value. In addition, when the sampling frequency is changed, the period adjustment value is changed.

The rotational angle position detection process of the present embodiment is mainly executed by the signal processing unit 100 using hardware resources in cooperation with the control program (not shown) stored in the storage medium.

Hereinafter, details of the rotational angle position detection processing are explained step by step according to the flow chart of FIG. 8 .

(Step S101)

First, the rotation angle position calculation unit 110 performs rotation angle position calculation processing.

When the rotating body 2 (FIG. 2) rotates once, the A-phase signal (sine wave signal sin) and the B-phase signal (sinusoidal wave signal cos) shown in FIG. periodic output. The rotational angle position calculating section 110 uses these A phases amplified by the amplifier section 90 (amplifier sections 90(+A), 90(-A), 90(+B), 90(-B))). The Lissajous figure shown in FIG. 4D is calculated from the signal and the B-phase signal, θ = tan ^-1 (sin/cos) is calculated from the sinusoidal signal sin, cos, and the angular position (θ) of the moving object is calculated. . Further, in the present embodiment, the first Hall element 61 and the second Hall element 62 are disposed at positions shifted by 90° (π/2) as viewed from the center of the magnet 20. For this reason, by combining the outputs of the first Hall element 61 and the second Hall element 62, it is possible to know which section of the sinusoidal signal sin, cos the current position is located. Therefore, the encoder unit 10, based on the detection result in the potato sensor 4, the detection result in the first Hall element 61, and the detection result in the second Hall element 62, the rotating body 2 ) calculates the rotation angle position as absolute angular position information. Thereby, absolute operation can be performed.

Further, the rotational angle position calculation unit 110 calculates the difference between the rotational angle position at the current sampling time and the rotational angle position at the previous sampling time as the angular displacement value D'.

(Step S102)

Next, the correction unit 130 performs a speed ratio calculation process.

As described above, the correction unit 130 can calculate the rotational speed ω' (current rotational speed) in the use state in the specific rotational speed ω by the following formula (2) Do.

ω' = (D'/D) × ω... … Equation (2)

Here, the angular displacement value D is a specific angular displacement value related to a specific rotational speed ω, as described above.

Specifically, the correction unit 130 calculates the value of D'/D as a speed ratio.

(Step S103)

Next, the correction unit 130 performs a correction value calculation process.

The correction unit 130 first divides the rotation angle position by the rotation angle position calculation unit 110 by a specific rounding value, and calculates the division angle position corresponding to the correction amount table 120 . As in the example described above, when the angular resolution R is 20 bits, the correction unit 130 divides the rotation angular position by 8192 as a specific rounding value to calculate divided angular positions from 0 to 255. Correction unit 130 can speed up this calculation by right-shifting the rotation angle position by 14 bits instead of dividing by 8192. The correction unit 130 obtains the correction amount corresponding to the division angle position from the A-phase signal table 121 for the A-phase signal and from the B-phase signal table 122 for the B-phase signal, respectively.

Further, the correction unit 130 calculates the final correction value by the following equation (3):

Correction value = correction amount × speed ratio × cycle adjustment value/(specific rounding value) … … Equation (3)

At this time, the correcting unit 130 calculates correction values for the A-phase signal and the B-phase signal, respectively.

(Step S104)

Next, the correction unit 130 determines whether or not the sampling period has changed. The correcting unit 130 determines YES when the sampling period is changed by a control signal or the like from the host device 13 or the control device 12. Correction unit 130 determines NO in other cases.

In the case of YES, the correction unit 130 proceeds the process to step S105.

In the case of NO, the correction unit 130 ends the rotation angle position detection process.

(Step S105)

When the sampling period is changed, the correction unit 130 performs a period adjustment value calculation process.

When the sampling period is changed, the correcting unit 130 calculates a period adjustment value based on the sampling period T of the specific rotational speed ω.

For example, when the sampling period T of the specific rotation speed ω is 62.5 μsec, the correction unit 130 adjusts the period as 62.5/40 = 25/16 when changing this to 40 μsec. Calculate the value.

In addition, the correction unit 130 similarly changes the sampling period to 50 μsec, 5/4, 80 μsec, 25/32, 100 μsec, 5/8, 125 μsec, 1/ 2, etc., the period adjustment value is calculated. In this way, by setting the denominator of the cycle adjustment value to a value of a power of 2, the correction unit 130 can calculate the above-described equation (3) at high speed by bit shifting.

Further, the correction unit 130 calculates a correction value by applying the calculated cycle adjustment value from the time of calculating the next correction value.

With the above, the rotation angle position detection process according to the embodiment of the present invention is ended.

[Main Effects Related to Embodiments of the Invention]

By configuring as above, the following effects can be obtained.

[0003] Conventionally, magnetic encoders have been problematic in that an error (velocity ripple) occurs in an output value during operation. This is because power generation occurs in the wiring pattern when the magnet rotates near the substrate, and the induced voltage is superimposed on the output of the magnetic sensor.

In contrast, the encoder unit 10 according to the embodiment of the present invention includes a rotation angle position calculation unit 110 that detects the rotation angle position from the signal of the detection element, and the signal of the detection element is proportional to the rotation speed. A correction amount table 120 for storing correction amounts for eliminating errors overlapping in correspondence to division angle positions divided during one rotation at a specific rotational speed, and a speed ratio between the rotational speed and the specific rotational speed in use and a correction unit 130 that calculates a correction value corresponding to the calculated speed ratio and division angle position from the correction amount stored in the correction amount table 120.

By configuring in this way, it becomes possible to correct the error overlapping in proportion to the rotational speed by converting it according to the rotational speed in the use state. In this way, it is possible to correct the rotational angle position corresponding to the usage condition, and increase the detection accuracy of the rotational angle position.

Further, in the encoder unit 10 according to the embodiment of the present invention, the detecting element faces a movable object to be detected having a magnet 20 in which a pair of magnetic poles of the S pole and the N pole are magnetized, and the magnet 20 is opposed. The error superimposed on the signal of the detection element in proportion to the rotational speed is induced voltage induced in the stationary body 3 by the rotation of the magnet 20. It is characterized by being

By configuring in this way, the following effects are obtained. Here, the induced voltage induced by the rotating magnetic flux is generated in proportion to the rotating speed. For this reason, by storing the correction amount at a specific rotational speed in a correction table and calculating the speed ratio between the rotational speed and the specific rotational speed in use, and converting according to the speed ratio, appropriate correction can be easily performed. there is. In addition, since only the correction amount at a specific rotational speed needs to be stored in the correction amount table 120, the creation time of the correction amount table 120 can be reduced, and the cost of the storage medium can be reduced.

Further, in the encoder unit 10 according to the embodiment of the present invention, when the correction unit 130 calculates the speed ratio between the rotation speed in use and the specific rotation speed, the specific rotation speed ω (rpm) is calculated by the following formula (1),

ω = D/T/R × 60 … … Equation (1)

where R is the angular resolution, T is the sampling period (seconds), D is the angular displacement value,

In this specific rotational speed (ω), the rotational speed (ω') in the use state is calculated by the following formula (2).

ω' = (D'/D) × ω... … Equation (2)

Here, D' is characterized by being a division angular difference value that is a difference between an angular displacement value at the current sampling time and an angular displacement value at one previous sampling time.

By configuring in this way, the rotational speed in the use state can be calculated only by calculating the division angle difference value between one sampling period. For this reason, the amount of correction in the rotational speed in a used state can be easily calculated.

Further, the encoder unit 10 according to the embodiment of the present invention is characterized in that the correction unit 130 corrects the rotational angle position in the entire range of the number of revolutions in the use state.

With this configuration, it is not necessary to distinguish depending on the case whether or not the rotational angle position is corrected according to the rotational speed in the use state. For this reason, calculation of correction can be made easy, and cost can be reduced.

Further, since the error due to the induced electromotive force is proportional to the rotational speed, the amount of correction also decreases when the rotational speed is low. For this reason, even if the correction is performed in the entire range of the rotation speed in the use condition, the error is not increased. In addition, it is possible to reduce differences in error characteristics due to classification according to cases.

In addition, the encoder part 10 concerning the embodiment of the present invention, the detecting element, the magnetic sensor 4 includes an A-phase sensor and a B-phase sensor corresponding to the displacement of the movable object to be detected, and from the A-phase sensor A sine wave phase A signal is output, a sine wave phase B signal is output from the B phase sensor, the phase difference between the A phase signal and the B phase signal is approximately π/2, and the rotation angle position calculation unit 110, By calculating and analyzing the Lissajous waveform on the XY plane from the A-phase signal and the B-phase signal, the angular position of the movable object to be detected is detected, the rotational angular position is calculated from the detected angular position, and the correction amount table 120 is A A correction amount is stored for each of the phase signal and the B-phase signal, and the correction unit 130 calculates each of the A-phase signal and the B-phase signal from the correction amount of the A-phase signal and the B-phase signal in the correction amount table 120. It is characterized in that a correction value is calculated and corrected for .

With this configuration, even if the overlapping error in proportion to the rotational speed differs between the A-phase signal and the B-phase signal, since both the A-phase signal and the B-phase signal have correction tables, it is possible to obtain an optimum correction value for each. It happens. Therefore, the detection accuracy of the rotation angle position can be improved.

In addition, the encoder unit 10 according to the embodiment of the present invention is a fixed body 3, the magnetic sensor 4 is mounted on one side, and the double-sided substrate on which the semiconductor device 9 is mounted on the other side ( 5), and the semiconductor device 9 is provided with an amplifier unit 90 that amplifies the output signal from the magnetic sensor 4, and the magnetic sensor 4 and the semiconductor device 9 are at least part of each other Arranged at overlapping positions in the thickness direction of the double-sided board 5, the magnetic sensor 4 and the semiconductor device 9 are at least one of the magnetic sensor and the semiconductor device in the double-sided board in the thickness direction of the double-sided board 5 It is characterized in that it is electrically connected through a plurality of through holes (50) formed at overlapping positions in

By comprising in this way, since the through hole 50 is formed in the position overlapping with at least one of the magnetically sensitive sensor 4 and the semiconductor device 9, the transmission path of the output from the magnetically sensitive sensor 4 becomes short. For this reason, the induced noise which arises in the transmission path of the output from the magnetically sensitive sensor 4 can become small, and the influence of the noise resulting from an induced voltage can be alleviated.

In addition, the encoder unit 10 according to the embodiment of the present invention, in the potato sensor 4, the potato sensor side first wiring and the potato sensor side chip between the potato sensor side chip and the first output terminal on which the potato film is formed The first induced voltage generated by linking the second wire on the magnetic sensor side between the second output terminals with the magnetic flux of the magnet 20, the first through hole and the second output corresponding to the first output terminal among the plurality of through holes The second induced voltage generated when the second through hole corresponding to the terminal links with the magnetic flux of the magnet 20, and in the semiconductor device 9, to the amplifier side chip on which the amplifier section 90 is formed and to the first output terminal The first wiring on the amplifier side between the first input terminal electrically connected and the second wiring on the amplifier side between the second input terminal electrically connected to the chip on the amplifier side and the second output terminal are linked with the magnetic flux of the magnet 20 The third induced voltage generated by doing this is characterized in that it is formed so that one induced voltage and two other induced voltages disappear.

By configuring in this way, the induced voltages can be canceled with each other, and the influence of noise caused by the induced voltage can be alleviated.

Further, in the encoder unit 10 according to the embodiment of the present invention, the correcting unit 130 determines the sampling period T of the specific rotational speed ω and the changed sampling period T' when the sampling period is changed. A corresponding period adjustment value is calculated, and a correction value is calculated by applying the period adjustment value.

With this configuration, even if it is necessary to change the sampling cycle due to a change in the design stage or a change in operation mode during use, the rotation angle position can be corrected by easily using the previously created correction table. For this reason, development cost can be reduced.

(Example)

Next, with reference to FIGS. 9A and 9B , an example in which the signal processing unit 100 corrects the output of the encoder unit 10 in the circuit layout of the present embodiment will be described. In addition, the following examples do not limit the present invention.

At a rotational speed of 5859 rpm, the motor was rotated by driving by another device, and the values of the A-phase signal (sin) and B-phase signal (cos) were simultaneously acquired at a sampling period (T) of 80 µsec. An angular error was calculated from the Lissajous figure of the acquired A-phase signal and B-phase signal. On the waveform of this Lissajous figure, a SIN wave of one cycle was superimposed, and the error was calculated again.

In addition, the phase and amplitude of the superimposed waveform were changed, and the value at which the error was minimized was calculated as the generated voltage of the induced voltage.

FIG. 9A is a comparative example and is a graph of a result of calculating the generated voltage when the rotational speed is changed in a state where correction is not performed by the signal processing unit 100. FIG. The horizontal axis represents the value of the rotation angle position. The vertical axis represents the value (digit) obtained by A/D conversion of the generated voltage. When error correction is not performed, it can be seen that the generated voltage is generated in proportion to the rotation speed. At this time, at 8000 rpm, the maximum value of the error due to the COS generation voltage is amplitude: 3250 digits/20 bit resolution, phase: 14.75°, and the maximum value of the error due to the SIN generation voltage is amplitude: 3575 digits/20 bits. bit resolution, and phase: became -48.875°.

9B is an example, and is a graph of a result of calculating the generated voltage when the rotational speed is changed in a state of correction by the signal processing unit 100. It is understood that the effect of the error due to the induced voltage proportional to the rotational speed could be mitigated by performing the correction. As a result, the error due to the COS power generation voltage and the SIN power generation voltage could be reduced to 1/5 or less of the maximum value.

[Other Embodiments]

Moreover, in the above-mentioned embodiment, the magnetic sensor 4 described about the example facing the magnet 20 in the direction of the rotation center axis line L. However, you may apply the circuit of this embodiment to the encoder part 10 in which the magnetic sensor 4 opposes the outer peripheral surface or outer peripheral surface of the ring-shaped magnet 20.

By configuring in this way, variations in the configuration of the encoder section 10 can be increased and design can be facilitated.

Further, in the above embodiment, the transmission path from the first land (land 51 (+A)) for the magnetic sensor to the first land (land (53 (+A))) for the semiconductor device, and the second land for the magnetic sensor The position of the transmission path from the land (land 51(-A)) to the second land (land 53(-A)) for semiconductor devices is switched on the other side 502 of the double-sided substrate 5. For this reason, the third induced voltage is canceled by the first induced voltage and the second induced voltage. In contrast, the transmission path from the first land (land 51 (+A)) for the magnetic sensor to the first land (land (53 (+A))) for the semiconductor device, and the second land (land 51 (+A)) for the magnetic sensor The transmission path from 51(-A)) to the second land for semiconductor devices (land 53(-A)) adopts a configuration in which the position is switched on one side 501 of the double-sided substrate 5. You can do it. In this case, the first induced voltage is canceled by the second induced voltage and the third induced voltage. In this case, when viewed from the direction of the rotation center axis (L), connecting the first land (land (51 (+A))) for the magnetic sensor and the second land (land (51 (-A))) for the magnetic sensor Regarding the virtual line, a virtual line connecting the first land (land 53(+A)) for the semiconductor device and the second land (land 53(-A)) for the semiconductor device, and the first through hole ( At least one set of virtual lines among the virtual lines connecting the through hole 50(+A) and the second through hole (through hole 50(-A)) extends in parallel. The description is omitted, but the B phase is also the same.

With this configuration, the design can be optimized so as to flexibly suppress the generation of the induced voltage, and the error can be reduced.

Further, in the above-described embodiment, the influence of the error due to the induced voltage is reduced by the layout of the circuit and the structure of the signal processing unit 100. However, it is also possible to reduce the influence of the error only by the configuration of the signal processing unit 100.

By configuring in this way, the design of the board can be made flexible, and the cost can be reduced.

In addition, in the embodiment described above, an example in which a correction table was prepared for each of the A-phase signal and the B-phase signal was described. However, one correction table corresponding to the angle of the Lissajous figure calculated from the A-phase signal and the B-phase signal may be prepared.

With this configuration, the capacity of the correction table in the storage medium can be reduced, and since computational resources can also be reduced, cost can be reduced.

In addition, the configuration and operation of the above embodiment are examples, and it goes without saying that they can be appropriately changed and implemented within a range not departing from the spirit of the present invention.

1: Encoder device
2: rotating body
3 : fixture
4: Potato sensor (Sensor IC)
5: double-sided board
9: semiconductor device (amplifier IC)
10: encoder unit
11: motor
12: control device
13: Parent device
20: Magnet
21: magnetizing surface
40: chip (potato sensor side chip)
41 to 44: Potato film
45: element substrate
47: wiring on the magnetic sensor side between the element board (chip) of the potato sensor and the output terminal
47(+A): Potato sensor side wiring (potato sensor side 1st wiring)
47(-A): Potato sensor side wiring (potato sensor side 2nd wiring)
47(+B): Potato sensor side wiring (potato sensor side 1st wiring)
47(-B): Potato sensor side wiring (potato sensor side 2nd wiring)
48: output terminal of potato sensor
48(+A): output terminal (first output terminal of potato sensor)
48(-A): output terminal (second output terminal of potato sensor)
48(+B): output terminal (first output terminal of potato sensor)
48(-B): output terminal (second output terminal of potato sensor)
48(Vcc) : Power terminal
48(GND): ground terminal
50: through hole
50(+A): 1st through hole
50(-A): 2nd through hole
50 (+B): 1st through hole
50(-B): 2nd through hole
51: Potato sensor side land
51(+A): land (first land for sensor sensor)
51(-A): land (second land for sensor sensor)
51 (+B): land (first land for sensor sensor)
51(-B): land (second land for sensor sensor)
52: wiring of double-sided board
53: semiconductor device side land
53 (+A): land (first land for semiconductor devices)
53(-A): land (second land for semiconductor devices)
53 (+B): land (first land for semiconductor devices)
53(-B): land (second land for semiconductor devices)
54: wiring of double-sided board
55: Rand
61: first hall element
62: second hall element
90, 95, 96: amplifier unit
93 Amplifier-side wiring between the chip of the semiconductor device and the input terminal
93 (+A): amplifier side wiring (amplifier side 1st wiring)
93(-A): amplifier side wiring (amplifier side second wiring)
93 (+B): amplifier side wiring (amplifier side 1st wiring)
93(-B): amplifier side wiring (amplifier side second wiring)
97: chip (amplifier side chip)
98: input terminal (input terminal of semiconductor device)
98 (+A): input terminal (first input terminal of semiconductor device)
98(-A): input terminal (second input terminal of semiconductor device)
98 (+B): input terminal (first input terminal of semiconductor device)
98(-B): input terminal (second input terminal of semiconductor device)
100: signal processing unit
110: rotation angle position calculation unit
120: correction amount table
121: phase A signal table
122: phase B signal table
130: correction unit
501: one way
502: other side
L: axis of rotation
X : control system

Claims (16)

An encoder provided with a rotation angle position calculating means for detecting a rotation angle position from a signal of a detection element, comprising:
A correction amount table for storing a correction amount for eliminating an error superimposed on the signal of the detection element in proportion to the rotational speed in correspondence with divided angular positions during one rotation at a specific rotational speed;
A speed ratio between a rotational speed in a use state and the specific rotational speed is calculated, a correction value corresponding to the calculated speed ratio and the division angle position is calculated from the correction amount stored in the correction amount table, and the rotation angle is calculated. correction means for correcting the rotation angle position detected by the position calculation means by the correction value;
The detection element,
It includes a movable object having a magnet in which a pair of magnetic poles of the S pole and the N pole are magnetized, and a stationary body on which a magnetic sensor facing the magnet is mounted,
The error superimposed on the signal of the detection element in proportion to the rotational speed is an induced voltage induced in the stationary body by rotation of the magnet,
The magnetic sensor includes an A-phase sensor and a B-phase sensor corresponding to the displacement of the movable object to be detected,
A sine wave-type A-phase signal is output from the A-phase sensor, and a sine-wave-type B-phase signal is output from the B-phase sensor;
The phase difference between the phase A signal and the phase B signal is π/2,
The rotation angle position calculation means,
Detecting an angular position of the movable object to be detected by calculating and analyzing a Lissajous waveform on an XY plane from the A-phase signal and the B-phase signal, and calculating the rotational angular position based on the detected angular position;
The correction amount table,
A correction amount is stored for each of the A-phase signal and the B-phase signal;
The correction means,
and calculating and correcting the correction value for each of the A-phase signal and the B-phase signal from the respective correction amounts of the A-phase signal and the B-phase signal in the correction amount table. delete According to claim 1,
The correction means,
When calculating the speed ratio of the rotational speed in the use state and the specific rotational speed,
The specific rotational speed is the relationship of the following formula (1),
ω = D/T/R × 60 … … Equation (1)
where ω is a specific rotational speed (rpm), R is an angular resolution, T is a sampling period (seconds), D is a specific angular displacement value,
The rotation speed in the use state is calculated by the following formula (2),
ω' = (D'/D) × ω... … Equation (2)
Here, ω' is the rotational speed (rpm) in the use state, and D' is a division angular difference value that is the difference between the angular displacement value at the current sampling time and the angular displacement value at the previous sampling time. Encoder characterized in that. According to claim 3,
The correction means,
An encoder characterized in that it corrects the rotational angular position in the entire range of the rotational speed in the use condition. delete According to claim 1,
The fixture is
Having a double-sided board on which the magnetic sensor is mounted on one side and a semiconductor device is mounted on the other side,
The semiconductor device includes an amplifier unit for amplifying the output signal from the potato sensor,
The magnetic sensor and the semiconductor device are disposed at a position where at least a part overlaps each other in the thickness direction of the double-sided board,
The magnetic sensor and the semiconductor device are electrically connected to at least one of the magnetic sensor and the semiconductor device in the double-sided board through a plurality of through-holes formed at overlapping positions in the thickness direction of the double-sided board. Encoder to do. According to claim 6,
In the magnetic sensor, the magnetic sensor-side first wiring between the potato sensor-side chip and the first output terminal on which the magnetic film is formed and the magnetic sensor-side second wiring between the potato sensor-side chip and the second output terminal are magnetic flux of the magnet A first induced voltage generated by linking with
A second induced voltage generated when a first through hole corresponding to a first output terminal and a second through hole corresponding to a second output terminal among the plurality of through holes interlink with the magnetic flux of the magnet; and
In the semiconductor device, an amplifier-side first wiring between an amplifier-side chip formed with the amplifier unit and a first input terminal electrically connected to the first output terminal, and electrically connected to the amplifier-side chip and a second output terminal. The third induced voltage generated when the second wiring on the amplifier side between the second input terminals interlinks with the magnetic flux of the magnet,
An encoder characterized in that it is formed so that one of the induced voltages and the other two induced voltages disappear. delete delete delete delete The method of any one of claims 1, 3, 4, 6 and 7,
The correction means,
When the sampling period is changed, the period adjustment value corresponding to the sampling period of the specific rotational speed and the changed sampling period is calculated, and a correction value is calculated by applying the period adjustment value. A rotation angle position calculation method executed by an encoder that detects a rotation angle position from a signal of a detection element, comprising:
A correction amount that eliminates an error superimposed on the signal of the detection element in proportion to the rotational speed is stored in a correction amount table corresponding to a specific rotational speed and divided angular positions divided during one rotation,
A speed ratio between a rotational speed in use and the specific rotational speed is calculated, a correction value corresponding to the calculated speed ratio and the division angle position is calculated from the correction amount stored in the correction amount table, and the correction value By correcting the signal of the detection element,
Calculate the rotation angle position by the corrected signal of the detecting element;
The detection element includes a movable object having a magnet magnetized with a pair of S and N poles, and a fixed body mounted with a magnetic sensor facing the magnet,
The magnetic sensor includes an A-phase sensor and a B-phase sensor corresponding to the displacement of the movable object to be detected,
A sine wave-type A-phase signal is output from the A-phase sensor, and a sine-wave-type B-phase signal is output from the B-phase sensor;
The phase difference between the phase A signal and the phase B signal is π/2,
The correction amount table stores correction amounts for each of the A-phase signal and the B-phase signal,
Detecting an angular position of the movable object to be detected by calculating and analyzing a Lissajous waveform on an XY plane from the A-phase signal and the B-phase signal, and calculating the rotational angular position based on the detected angular position;
The rotation angle position calculation method characterized by calculating and correcting the correction value for each of the A-phase signal and the B-phase signal from the respective correction amounts of the A-phase signal and the B-phase signal in the correction amount table. According to claim 13,
The specific rotational speed is the relationship of the following formula (1),
ω = D/T/R × 60 … … Equation (1)
where ω is a specific rotational speed (rpm), R is an angular resolution, T is a sampling period (seconds), D is a specific angular displacement value,
The rotation speed in the use state is represented by the following formula (2),
ω' = (D'/D) × ω... … Equation (2)
Here, ω' is the rotational speed (rpm) in the use state, D' is a division angular difference value that is the difference between the angular displacement value at the current sampling time and the angular displacement value at the previous sampling time, ,
A rotation angle position calculation method characterized in that the value of (D'/D) is calculated as the speed ratio. delete 15. The method of claim 14,
When the sampling period is changed, calculating the sampling period of the specific rotational speed and a period adjustment value corresponding to the changed sampling period, and calculating a correction value by applying the period adjustment value.

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