JPH09179630A - Method and device for detecting original point of pulse motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse motor origin detection method capable of accurately detecting a stop position even when load is changed in the case of driving a device having large load change by a pulse motor and an origin detector using the method. SOLUTION: The detection method detects a needle to be rotated together with an output shaft 2 by a fixed sensor 5, drives a latch circuit 6 by a detection signal, and detects the origin position of the pulse motor 1 in accordance with the output state of the circuit 6. When the needle 4 exists within the detection area of the sensor 5 in the inverted state of an output from the circuit 6, the position of the needle 4 is judged as an original point, and when the needle 4 does not exist within the detection area, the motor 1 is inverted. When the output of the sensor 5 is changed at the time of inverting the motor 1, the inverted and stopped position is judged as an original point, and when the output of the sensor 5 is not changed, the motor 1 is rotated forward again and the stopped position of the motor 1 is judged as an original point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an origin position detecting method for detecting the origin position of a rotation angle of a pulse motor and an origin position detecting device using this detecting method.

[0002]

2. Description of the Related Art In general, a pulse motor is commercially available with a rotary encoder added thereto in order to accurately define a stop position of a driven device. The rotary encoder is used to continuously output a rotation angle signal while the output shaft of the pulse motor makes one rotation, and to detect the rotational position of the output shaft. However, the rotary encoder does not have the function of detecting the origin position of the output shaft. For this reason, the rotary encoder is provided with an origin detection sensor that outputs one pulse at a predetermined origin position during one rotation of the shaft.

The origin detection sensor is roughly classified into a type using an optical sensor and a type using a magnetic sensor. The example shown in FIG. 6 shows the structure of an optical sensor type origin detection sensor. A sensor disk 3 is attached to the output shaft 2 of the pulse motor 1, a movable element 4 constituted by a slit is provided at a predetermined rotation angle position of the sensor disk 3, and the movable element 4 is a fixed sensor 5 constituted by a light transmission type sensor. The structure is such that the position of the mover 4 is detected to detect the origin of the rotation direction. A permanent magnet having an N-S pole is used as a movable element in an origin detection sensor of a type using a magnetic sensor, and a magnetic sensitive element such as a Hall element is used as a fixed sensor.

[0004]

In the origin detecting sensor, when the movable element 4 is mounted so that the stop position and the fixed sensor 5 are aligned with each other, as shown in FIG. Since light is transmitted to the fixed sensor 5 through the fixed sensor 5, the fixed sensor 5 continuously outputs the origin detection signal PJ of logic "1" as shown in FIG. 7B. In the case of a magnetic sensor, the origin detection signal of logic "1" can be obtained if the mover faces the magnetic sensitive element and stops.

However, since the rotation angle Δθ of one step of the pulse motor 1 is small, it is extremely difficult to match the stop position of the mover 4 and the position of the fixed sensor 5. Further, even if the position of the fixed sensor 5 and the stop position of the mover 4 match in the unloaded state, when the mechanical load is applied, the load causes a shift in the stopped position, and the fixed sensor in the stopped state. In some cases, the position of 5 and the position of the mover 4 do not match.

Therefore, in general, as shown in FIG. 8A, the relationship between the stop position of the mover 4 and the position of the fixed sensor 5 is often located in the middle of the rotation angle range of the pulse motor 1. Therefore, the origin detection signal output from the fixed sensor 5 is shown in FIG. 8B.
As shown in, since the mover 4 is obtained by the pulse PP having a narrow pulse width every time the mover 4 passes the position of the fixed sensor 5, this pulse PP is conventionally given to the latch circuit, and the latch circuit is inverted by the pulse PP. The origin detection signal PJ shown in FIG. 8C is obtained.

When the latch circuit is used, the following inconvenience occurs. In other words, the pulse motor 1 may exceed the stop position depending on the load, generate an overshoot OB as shown in FIG. 9, and stop while vibrating. Therefore, if the mover 4 slightly transmits light to the fixed sensor 5 or gives a magnetic field by the overshoot OB and returns to the original state, this overshoot O
The latch circuit is triggered by B, the latch circuit is inverted, and the origin detection signal PJ is output at the rotation angle position θ ₀ .

On the other hand, even in the same device, if the amount of overshoot OB fluctuates due to load fluctuations and the amount of overshoot OB becomes small as shown in FIG. 10, for example, this is different from the case of FIG. There is a problem that the origin is detected at the rotation angle position θ ₁ . In addition, FIG.
As shown in, when the amount of overshoot OB exists at a level of two or more steps of the pulse motor, there is a drawback that the detection position ST of the origin becomes a position separated by two steps or more.

An object of the present invention is to provide a pulse motor origin detecting device using a latch circuit, which is capable of always defining a predetermined rotation angle position as the origin even if the amount of overshoot varies. Detection method,
The present invention intends to provide an origin detecting device using the method.

[0010]

According to Claims 1 and 2 of the present application, in a pulse motor origin detecting device constructed by combining an origin detecting sensor and a latch circuit, the pulse motor is operated once the latch circuit is reversed. Rotate in the opposite direction. If a pulse is generated from the fixed sensor during this reverse rotation, the position at which it reversely rotated and stopped is determined to be the origin, and if no pulse is generated from the fixed sensor during reverse rotation, the original rotation angle position (rotation before reverse rotation An origin detection method for determining an angular position) as the origin and an origin detection apparatus using this detection method are proposed.

According to the first and second aspects of the present invention, an overshoot occurs in the movement of the output shaft of the pulse motor, and when the origin position is detected by this overshoot, the pulse motor rotates in steps. Even if the origin position is detected in the presence state, the same step position can be determined as the origin position in any case. Therefore, according to the present invention, there is an advantage that the load stop position can be accurately maintained regardless of whether the load fluctuates and overshoot occurs or no overshoot occurs. To be

According to the inventions of claims 3 and 4 of this application, even if the overshoot amount of the pulse motor exists in two or more steps, the origin detection position can be defined as the normal origin position and the origin detection device. Is provided. Therefore, in the inventions proposed in claims 3 and 4, a mover is attached to the output shaft of the pulse motor, the passage of the mover is detected by a fixed sensor, and the latch circuit is triggered by the detection signal of the fixed sensor, In the pulse motor origin detection method that detects the origin of the rotation angle of the pulse motor by the reversing operation of, the pulse motor rotates in the forward direction by the supply of the forward rotation pulse, and the mover moves the position of the fixed sensor during this rotation. When the position of the mover does not match the position of the fixed sensor in the control state where the output of the latch circuit is passed and the output of the latch circuit is inverted and the inversion operation is detected to stop the pulse motor, the rotation angle position of the pulse motor is exceeded. The number of rotation steps is incremented by +1 each time it is returned to the retracted position that is sufficient to eliminate the effect of the chute and is rotated in the forward direction from this retracted position. The pulse motor origin position detection method and this origin detection method that repeats normal rotation and reverse rotation of the pulse motor until the mover passes the position of the fixed sensor when returning to the retracted position by repeating this. The proposed origin detection device is used.

According to the third and fourth aspects of the present invention, even if the amount of overshoot reaches the amount of several steps of the pulse motor, it is possible to detect the predetermined rotational position as the origin position without fail. it can.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for detecting the origin position of a pulse motor according to the invention of claim 1 of this application will be described with reference to FIGS. 1 and 2. 1A and 1B show the operating conditions that characterize the present invention. FIG. 2 shows the origin detection operation of the pulse motor which is made in a state where the stop position of the mover 4 which operates normally even in the conventional technique and the installation position of the fixed sensor 5 coincide with each other. In the case of a pulse motor in which the stop position of the mover 4 and the installation position of the fixed sensor 5 match, the output of the fixed sensor 5 becomes H logic at the end of the overshoot when the latch circuit is reversed. In this case, the stopped step position is determined as the origin position ST as it is.

On the other hand, FIGS. 1A and 1B show the case of a pulse motor made in a state where the stop position of the mover 4 and the position of the fixed sensor 5 do not match. The stop position of the mover 4,
In the case of a pulse motor in which the positions of the fixed sensor 5 do not match, the output of the fixed sensor 5 becomes L logic at the end of the overshoot even if the latch circuit is reversed. When the output of the latch circuit is H logic and the output of the fixed sensor 5 is L logic, one reverse pulse for rotating the pulse motor in the reverse direction is given in the present invention. At the time of supplying this reverse pulse,
In the case of FIG. 1A, the output of the fixed sensor 5 does not change. If the output of the fixed sensor 5 does not change, a pulse that rotates in the forward direction is applied again, and the stop step position is set to the origin position S.
Judge as T.

In the example shown in FIG. 1B, when a reverse pulse is supplied to the pulse motor, the fixed sensor 5 detects passage of the mover 4. When a change occurs in the fixed sensor 5, the stop step position after supplying the reverse pulse is determined as the origin position ST. Thus, according to the origin detection method of the present invention, in either case, the latch circuit is inverted due to overshoot as shown in FIG. 1A or the latch circuit is inverted during the step rotation shown in FIG. 1B. Can determine the same step position as the origin position ST.
Therefore, in the case of a pulse motor in which the stop position of the mover 4 and the position of the fixed sensor 5 do not match, even if the load becomes light and the latch circuit is reversed due to overshoot, the load becomes heavy and the step Even if the latch circuit is reversed during rotation, the same step position is determined as the origin position ST in any case, and the stop position does not deviate.

FIG. 3 shows an embodiment of the pulse motor origin detection device proposed in claims 2 and 4 of this application. 1 in the figure
Is a pulse motor, 2 is an output shaft of the pulse motor 1, 3
Is a sensor disk attached to the output shaft 2, 4 is a mover, and 5 is a fixed sensor for detecting the position of the mover 4. The detection output of the fixed sensor 5 is given to the latch circuit 6, and the output of the latch circuit 6 and the detection output of the fixed sensor 5 are input to the origin detection device 10 according to the present invention. In the present invention, the origin detection device 10 includes a controller 11, a forward rotation pulse generator 12 controlled by the output of the controller 11, a reverse rotation pulse generator 13, and these forward rotation pulse generator 12 and reverse rotation pulse generator. It can be configured by a synthesizing circuit 14 that synthesizes the outputs of 13 and gives them to the pulse motor 1.

The controller 11 can be constituted by a generally known one-chip microcomputer. The one-chip microcomputer includes a central processing unit 11A, a RAM 11B used for temporarily storing the number of pulses supplied to the pulse motor 1, the output state of the latch circuit 6, the presence / absence of output of the fixed sensor 5, and the like. The ROM 11C stores a program for operating the device 11 as an origin detection device, an input port 11D, an output port 11E, and the like.

The detection signal of the fixed sensor 5 and the output signal of the latch circuit 6 are input to the input port 11D. The central processing unit 11A constantly monitors the output states of the latch circuit 6 and the fixed sensor 5. When the output of the latch circuit 6 is inverted to, for example, H logic, the operation of the normal rotation pulse generator 12 is stopped and the generation of the normal rotation pulse is stopped. With this,
The logic of the output of the fixed sensor 5 is read. The timing of this reading is to avoid the time when the rotation of the output shaft 2 of the pulse motor 1 vibrates due to overshoot, and
It is the timing to predict that the movement of has stopped. The output of the latch circuit 6 is held at H logic, and the fixed sensor 5
If the output of is also H logic, that position is determined as the origin position ST. In other words, the mover 4 has the detection area 5 of the fixed sensor 5.
When it exists in A, the position is determined as the origin position ST.

On the other hand, when the output of the fixed sensor 5 is L logic even though the output of the latch circuit 6 is H logic, the central processing unit 11A supplies the reverse pulse generator 13 through the output port 11E. A control signal for outputting one reverse pulse is given. The reverse rotation pulse generator 13 applies one reverse rotation pulse to the pulse motor 1 to rotate the output shaft 2 in the reverse direction by one pulse. After instructing the generation of the reverse rotation pulse, the central processing unit 11A monitors whether or not an output is generated in the fixed sensor 5.

If there is no change in the output of the fixed sensor 5, as shown in FIG. 1A, one forward rotation pulse is output again,
The step position at which the forward rotation pulse is applied and stopped is determined as the origin position ST. In contrast, as shown in FIG. 1B, after the reverse pulse is applied, as shown in FIG.
If a change occurs in the output of, the step position stopped by applying the reverse rotation pulse is determined as the origin position ST.
When one pulse is applied to the pulse motor 1 to return it to the original direction in the normal direction, as shown in FIG. 1, the overshoot OB causes the fixed sensor 5 to generate a signal again. The latch circuit 6 is inverted by this signal,
Since this reversing operation is the result of detecting the origin position ST, the reversing state is maintained.

As shown by dotted lines in FIGS. 1A and 1B, it is also possible to apply two or three reverse pulses to move the load sufficiently in the opposite direction and stop at the normal origin position ST. it can. In this way, by sufficiently moving in the opposite direction and stopping at the normal origin position, the effect of load backlash can be eliminated. In the embodiment shown in FIG. 3, the latch circuit 6 is provided outside the controller 11, but the RAM 11B provided inside the controller 11 is described.
The operation of the latch circuit can be performed by using a part of the memory cells.

FIG. 4 shows a waveform diagram for explaining the origin detection method of the pulse motor proposed in claim 3 of the present invention. FIG.
Then, the waveform after time T _A is expressed in one step, omitting the part which should be expressed in a step shape. The numbers on the scale indicate the number of steps. In the pulse motor origin detection method proposed in claim 3 of the present application, even when the amount of overshoot generated in the pulse motor 1 reaches several steps of the rotation step amount of the pulse motor 1, the specified rotation angle position is always set. The present invention proposes a method for detecting the origin position of a pulse motor that can detect the origin position.

That is, when the overshoot OB of the pulse motor 1 has an amplitude corresponding to, for example, two steps larger than the rotation amount of the pulse motor 1 for one step as shown in FIG. According to the pulse motor origin detection method proposed in 1), there is a possibility that a step position separated by two or more steps may be determined as the origin. Therefore, in the pulse motor origin detection method proposed in claim 3 of this application, it is determined whether or not the latch circuit 6 is inverted every time the pulse motor 1 is rotated in the forward direction, and the sensor disk 3 is provided with the determination. When the position of the mover 4 enters the detection area 5A of the fixed sensor 5 due to the overshoot OB, the latch circuit 6 is inverted. By reversing the output state of the latch circuit 6, the supply of the normal rotation pulse to the pulse motor 1 is stopped, and the pulse motor 1 is stopped.

The mover 4 with the pulse motor 1 stopped
It is determined whether or not the position has stopped within the detection area 5A of the fixed sensor 5. In this example, as shown in FIG. 4, the case where the mover 4 penetrates into the detection area 5A of the fixed sensor 5 due to the overshoot OB will be described.
The position of the mover 4 cannot stop within the detection area 5A of the fixed sensor 5. Therefore, in this case, control is performed to return the pulse motor 1 to the rotation angle position A sufficient to eliminate the influence of the overshoot OB. Hereafter, this rotation angle position A will be referred to as a retracted position. The retracted position A is the detection area 5A of the fixed sensor 5 due to the overshoot OB of the position of the mover 4 regardless of whether the pulse motor 1 rotates in the forward rotation direction or the reverse rotation direction from the retracted position A.
The position is not reached. The example shown in FIG. 4 shows a case where the retracted position A is a position that is reversely rotated by N = 3 steps from the first stop position.

From the state in which the rotational position of the pulse motor 1 is returned to the retracted position A, the pulse motor 1 is rotated in the forward direction again by N + 1 steps (forcibly ignoring the overshoot OB) to obtain N.
+1 step forward rotation and stop. At this time, mover 4
If the position of does not exist in the detection area 5A of the fixed sensor 5, the pulse motor 1 is rotated backward by N + 1 steps again,
Return to the retracted position A. Fixed sensor 5 when returning to the retracted position A
If there is no change in, rotate again in the forward direction by N + 2 steps.

As described above, according to the present invention, the amount of rotation in the forward direction is increased by +1 each time it returns to the retracted position A, so that even if the amount of overshoot OB is two steps or more, the mover 4 is moved. The position of can be gradually approached to the detection area 5A of the fixed sensor 5, and in the case of the pulse motor 1 which is made in a state where the stop position of the mover 4 does not match the detection area 5A of the fixed sensor 5, It is possible to drive the mover 4 into a state of stopping at a position where the mover 4 has passed the detection area 5A. When the mover 4 stops at a position that has passed the detection area 5A too much, the mover 4 passes through the detection area A when returning from the stop position to the retracted position A. By detecting the transmission of this light, the next movement from the retracted position A in the forward rotation direction (N
+2) Rotate by -1 step, and determine the stop position as the origin position ST in the rotation angle direction of the pulse motor 1.

By determining the origin position ST in this way, even if the amount of overshoot OB exists in two or more steps of the rotation angle step of the pulse motor 1, the detected origin position is always one step from the detection area 5A. You can approach within range. Even if the load fluctuates and the amount of overshoot OB changes, the detected origin position ST
Is immutable.

FIG. 5 is a flow chart for explaining the outline of a program for forming the origin detecting device using the pulse motor origin detecting method described in FIG. Step SP
₁ and SP ₂ constitute a routine for applying a forward rotation pulse to the pulse motor 1 to move the controlled object. That is, one forward rotation pulse is given to the pulse motor 1, the state of the latch circuit 6 (FIG. 3) is monitored every time the forward rotation pulse is supplied, and the forward rotation pulse is given until the state of the latch circuit 6 is reversed. to continue.

When it is detected in step SP ₂ that the output state of the latch circuit 6 is inverted, the process proceeds to step SP ₃ . In step SP ₃ in the stop position, it is determined whether the movable element 4 is present in the detection region 5A. When the movable element 4 is present in the detection region 5A proceeds to step SP _4, it determines its stop position as the home position ST.

In FIG. 5, the contents of the judgment block of step SP ₂ are indicated as A below, the contents of the judgment block of step SP ₃ are B, and the contents of the execution block of step SP ₃ are C.
Is displayed. If the mover 4 is not present in the detection area 5A branches to step SP _5, the reverse rotation pulse generator 13
(See FIG. 3), for example, three reverse pulses are generated.
At step SP ₆ , it is monitored whether the state of the fixed sensor 5 changes during the reverse rotation and the state of the latch circuit 6 is reversed again. If the state of the latch circuit 6 is reversed, step S
Proceed to P ₇ , the forward rotation pulse generator 12 receives the number of reverse rotation pulses N
= 1 from giving a command to generate two forward pulses -1, rotates the pulse motor 1 in two steps forward direction, it determines the stop position and the home position ST in step SP _8.

If the state of the latch circuit 6 does not change during the reverse rotation, the process branches to step SP ₉ . Step SP
_{In the case of 9} , four forward rotation pulses are generated by adding +1 to the number N of reverse rotation pulses generated. The state of the latch circuit 6 is monitored in step SP ₁₀ while the four forward rotation pulses are generated in step SP ₉ . When it is detected that the output state of the latch circuit 6 is inverted, the process proceeds to step SP ₁₁ . At step SP ₁₁ , it is checked whether or not the mover 4 is present in the detection area 5A. Origin position ST its position in the step SP ₁₂ when the movable element 4 is present in the detection area 5A
Is determined.

In step SP ₁₀ , the latch circuit 6
If the condition is detected that not inverted, branches to step SP _13, the pulse motor 1 gives five reverse pulse, back to the initial routine. In other words, if the state of the latch circuit 6 is not inverted even though N + 1 normal rotation pulses are applied in step SP ₉ , it is determined that some malfunction has occurred, and the operation of returning to the initial state is performed.

On the other hand, if it is determined in step SP ₁₁ that the position of the mover 4 does not exist within the detection area 5A, the process branches to step SP ₁₄ to give the pulse motor 1 four reverse rotation pulses. This whether the state of the latch circuit 6 changes monitored in step SP ₁₅ in reverse. If it is determined that the state of the latch circuit 6 has changed during reverse rotation, step S
Proceeds to P _15, N-1 = 3 is stepped rotated in the forward direction at step SP _15, it determines the stop position and the home position ST in step SP _17. If the state of the latch circuit 6 is not inverted during the reverse rotation branches to step SP _18, to generate N + 2 = 5 pulses in the forward direction. During the forward rotation, the state of the latch circuit 6 is monitored in step SP ₁₉ and it is determined whether or not the state of the latch circuit 6 is inverted during the forward rotation of 5 steps. When the state of the latch circuit 6 is reversed, step S
Proceeds to P _20, is determined in step SP ₂₁ if the movable element 4 is present in the range of the detection region 5A in that position the stop position as the home position ST.

In step SP ₁₉ , the pulse motor 1
When the state of the latch circuit 6 is not inverted during the normal rotation of 5 steps, it is determined that some malfunction has occurred as in the case of step SP ₁₃ , and a reverse pulse is generated in step SP _22. Generate 6 and return to the initial routine. In step SP _20, if the position of the movable element 4 is determined not to be included in the range of the detection area 5A branches to step SP _23, 5 or to generate a reverse pulse in step SP _23. When detecting that the state of the output of the latch circuit 6 is changed at step SP ₂₄ while raised this five reverse pulse, to generate 5-1 = 4 forward rotation pulse at step SP _25, in step SP ₂₆ determines the stop position and the home position ST.

Even if a control routine is continuously provided in the same manner,
Good, but here the amount of overshoot OB is 2 steps
Since it is set to a level, it is practically a step SP_{twenty three}, SP_{twenty four},
SP _{twenty five}If there is a routine of
You. The ROM 11 shown in FIG. 3 for the program shown in FIG.
Proposed in claim 4 of this application by incorporating in C
An origin detection device can be configured.

[0037]

As described above, according to the present invention, in the mechanical control system controlled by the pulse motor,
Even if an overshoot occurs when the pulse motor is stopped, it is possible to always detect a constant rotation angle position as the origin position and stop at that origin position. In particular, according to the origin detection method proposed in claim 3, even if the amount of overshooting corresponds to the rotation amount of two or more steps of the pulse motor, it can be stopped at the normal origin position. Further, even if the load of the mechanical system fluctuates and the amount of overshoot fluctuates, the origin position where detection and stop do not move. In this respect, for example, when applied to an IC carrier device, a positioning device or the like that requires high precision, the effect is significant.

[Brief description of the drawings]

FIG. 1 is a waveform diagram for explaining a pulse motor origin detection method proposed in claim 1 of this application.

FIG. 2 is a waveform diagram for explaining a detection operation of an origin detection sensor attached to a pulse motor.

FIG. 3 is a block diagram for explaining an embodiment of a pulse motor origin detection device proposed in claims 2 and 4 of this application.

FIG. 4 is a waveform diagram for explaining a pulse motor origin detection method proposed in claim 3 of this application.

FIG. 5 is a flowchart for explaining the outline of a program for configuring the pulse motor origin detection device proposed in claim 4 of this application.

FIG. 6 is a sectional view for explaining a relationship between a pulse motor and an origin detection sensor attached to the pulse motor.

FIG. 7 is a waveform diagram for explaining the operation of the conventional technique.

FIG. 8 is a waveform diagram similar to FIG.

FIG. 9 is a waveform chart for explaining the inconvenience of the conventional technique.

10 is a waveform diagram similar to FIG. 9.

FIG. 11 is a waveform diagram for explaining a problem to be solved by the invention proposed in claims 3 and 4 of this application.

[Explanation of symbols]

 1 pulse motor 2 output shaft 3 sensor disk 4 mover 5 fixed sensor 6 latch circuit 10 origin detection device 11 controller 12 forward rotation pulse generator 13 reverse rotation pulse generator

Claims (4)

[Claims] 1. A mover attached to a rotation output shaft of a pulse motor, and an origin detection sensor for detecting passage of the mover to detect an origin of a rotation angle position of the rotation output shaft.
In the pulse motor origin detection method in which the origin detection sensor triggers the latch circuit each time it detects passage of the mover and detects the origin of the rotation angle of the pulse motor by the inversion operation of the latch circuit, when the pulse motor is stopped. If the output of the fixed sensor does not match the position of the mover, a reverse pulse for rotating the pulse motor in the opposite direction is applied, and if the fixed sensor detects the mover again by this reverse pulse, the reverse pulse is generated. When the fixed position does not detect the mover by the supply of the reverse pulse, the step position rotated by one pulse in the reverse direction is determined as the normal origin. Pulse motor origin detection method that determines the step position as the proper origin. 2. A. A mover mounted on the rotation output shaft of the pulse motor for position detection, and B. A fixed sensor that detects the passage of the mover; A latch circuit driven by a detection signal of the fixed sensor while the pulse motor is rotating in the forward direction, and D. Stop control means for stopping the normal rotation state of the pulse motor when the output of the latch circuit is inverted; When the stop position of the mover stopped by the stop control means does not match the position of the fixed sensor, a reverse rotation pulse generator that reverses the pulse motor by a predetermined amount, and F. When the output of the fixed sensor is not generated in the state in which the reverse rotation pulse generator reversely rotates the pulse motor, a forward rotation pulse generator which again gives a forward rotation pulse to the pulse motor, and G. When the output of the latch circuit is reversed and the pulse motor is stopped by the stop control means, the fixed sensor detects the mover and the stop position is determined to be the origin position. When the position of the fixed sensor and the mover do not match in the stopped state, the reverse rotation pulse generator reverses the pulse motor, and the output of the fixed sensor is generated during this reverse rotation. When the position is judged as the origin position and the output of the fixed sensor is no signal at the time of reverse rotation, the position where the forward rotation pulse generator generates the forward rotation pulse and the pulse motor is rotated forward is judged as the origin position. A pulse motor origin detection device characterized by being configured with a controller that operates. 3. A mover attached to a rotation output shaft of a pulse motor, and an origin detection sensor for detecting passage of the mover to detect an origin of a rotation angle position of the rotation output shaft.
In this pulse motor origin detection method that triggers the latch circuit each time the origin detection sensor detects passage of the mover, and detects the origin of the rotation angle of the pulse motor by the inversion operation of the latch circuit, by supplying the forward rotation pulse. The pulse motor is rotated in the forward direction, and during this rotation, the mover passes the position of the fixed sensor and the output of the latch circuit is inverted, so that the pulse motor is stopped. If the position of does not match the position of the fixed sensor, the rotation angle position of the pulse motor is returned to a retracted position that is sufficiently distant from the stop position that is sufficient to eliminate the effect of overshoot, and the normal position is reset from this retracted position. Each time it is rotated in the rolling direction, the number of rotation steps is incremented by +1. A method for detecting the origin position of a pulse motor, characterized in that the forward rotation and the reverse rotation of the pulse motor are repeated until the pendulum passes the position of the fixed sensor. 4. A. A mover mounted on the rotation output shaft of the pulse motor for position detection, and B. A fixed sensor that detects the passage of the mover; A latch circuit driven by the detection signal of the fixed sensor in a state where the pulse motor rotates in the forward direction and is stopped; Stop control means for stopping the normal rotation state of the pulse motor when the output of the latch circuit is inverted; When the stop position of the mover stopped by the stop control means does not match the position of the fixed sensor, the pulse motor is reversely rotated by N steps to the retracted position sufficient to eliminate the influence of the overshoot of the pulse motor. A pulse generator, and F. When the output of the fixed sensor is not generated each time the reverse rotation pulse generator reverses the rotation position of the pulse motor to the retracted position, the normal rotation pulse is applied to the pulse motor by adding +1 to the reverse rotation step number N. A pulse generator, and G. If the output of the latch circuit is reversed and the pulse motor is stopped by the stop control means and the fixed sensor detects the mover, the stop position is determined to be the origin position, and the pulse motor stops. When the positions of the fixed sensor and the mover do not match with each other, the reverse rotation pulse generator reverses the pulse motor N steps to return the rotation angle position of the pulse motor to the retracted position, and at the time of reverse rotation, In the state where the output of the fixed sensor is generated, after the reverse rotation, it is normally rotated from the retracted position by N-1 steps to determine the step position as the origin position. A pulse motor origin detection device comprising a controller for giving a command to generate a reverse pulse to a reverse pulse generator.