JP2020006411A - Servo press apparatus and control method - Google Patents

Abstract

To reduce deviation of an origin position of a servo press apparatus for each operation that determines the origin position.SOLUTION: A servo press apparatus comprises: a servo motor which has a rotary shaft; a drive part which drives the servo motor; a ram which is driven by rotation of the rotary shaft; a rotation angle detection part which detects a rotation angle of the rotary shaft by angle data which indicates an angle from a reference angle during one rotation of the rotary shaft, and rotation number data which indicates the rotation number from the reference number which is a reference value of the rotation number of the rotary shaft and is a value indicating an origin position of the ram; an origin position detection part which detects the origin position; a rotation number data setting part which sets rotation number data to the reference number in response to detection of the origin position by the origin position detection part; and a drive signal generation part which generates a drive signal for controlling the drive part in such a manner that the reference angle of angle data, when rotation number data indicates the reference number, is so made as to be the reference position of the ram on the basis of angle data which is used for detection of the rotation angle of the rotary shaft by the rotation angle detection part, and rotation number data.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a servo press device and a control method.

  As an example of a device in which an electric motor is incorporated in a servo mechanism, a servo press device using a ball screw is known (Patent Document 1). In the servo press device described in Patent Literature 1, a servo amplifier outputs a current command to a servomotor based on a position / speed detection signal from a position / speed detector, which is an angle detector, and a drive command from a servo calculation unit. I do.

A servo motor angle detector used in a servo press device as described in Patent Literature 1 is not backed up by a power supply, and when the power is turned off, the rotation position information of the servo motor is cleared. When the power is turned off, the position information of the rotation of the servomotor is cleared, so in a servo press device as described in Patent Document 1, the position of the origin of the servo press device is determined by pressing the seat surface of the press device. The position where the mounted photointerrupter intersects with the position indicating bar mounted on the ram and the light of the photointerrupter is blocked is set as the origin. Here, the origin position of the servo press device is an absolute origin position in the vertical direction of the ram.
Hereinafter, the operation of determining the origin position of the servo press device is also referred to as an origin setting operation.

JP 2004-167548 A

  However, in the servo press device described in Patent Literature 1, the members supporting the photointerrupter and the position indicating bar have low rigidity, and vibrate during the origin setting operation of the servo press device. As a result of the vibration of the member supporting the photo interrupter and the position indicating bar, in the servo press device described in Patent Document 1, the signal of the photo interrupter causes chattering and the origin of the ram of the servo press device is increased. There is a problem that the position is different for each originating operation.

  The present invention has been made in view of the above points, and provides a servo press device and a control method capable of reducing the deviation of the origin position for each operation of determining the origin position of the servo press device.

  The present invention has been made to solve the above-described problems, and one embodiment of the present invention is a servo motor having a rotating shaft, a driving unit that drives the servo motor, and a driving unit that is driven by rotation of the rotating shaft. Ram, the rotation angle of the rotating shaft, angle data indicating an angle from a reference angle of one rotation of the rotating shaft, and a reference value of the number of rotations of the rotating shaft, the origin position of the ram, A rotation angle detection unit that detects the rotation number data indicating the number of rotations from the reference number of times, an origin position detection unit that detects the origin position, and that the origin position detection unit detects the origin position. According to the number of rotations, the number of rotations data setting unit to set the reference number of times, the angle data used by the rotation angle detection unit to detect the rotation angle of the rotating shaft, and the number of rotations data Base And a drive signal generation unit that generates a drive signal for controlling the drive unit using the reference angle of the angle data as a reference position of the ram when the number of rotations data indicates the reference number of times. It is.

  In one aspect of the present invention, in the above-described servo press device, the origin position detection unit detects the origin position based on a blur amount within a range of one rotation of the number of rotations.

  In one aspect of the present invention, in the above-described servo press device, the number of rotations is represented by a division angle obtained by dividing one rotation angle of the rotation angle as a unit of one rotation.

  In one embodiment of the present invention, in the servo press device described above, the drive signal generation unit sets the position corresponding to the position at which the division angle is equally divided into two at the reference number of times as the reference angle, and Generate

  Further, one embodiment of the present invention provides a servo motor having a rotating shaft, a driving unit for driving the servo motor, a ram driven by rotation of the rotating shaft, and an origin position detecting unit for detecting an origin position of the ram. Part, the rotation angle of the rotating shaft, angle data indicating an angle from a reference angle of one rotation of the rotating shaft, and a reference value of the number of rotations of the rotating shaft, a value indicating the origin position A rotation angle detection unit that detects by rotation number data indicating the number of rotations from a certain reference number, and a control method of a servo press device, wherein the origin position detection unit detects the origin position And a rotation number data setting step of setting the rotation number data to the reference number.

  According to the present invention, the deviation of the origin position can be reduced for each operation of determining the origin position of the servo press device.

It is a figure showing an example of composition of a servo press device concerning an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a configuration of a servo motor driver according to the embodiment of the present invention. It is a figure showing an example of processing of an origin search operation concerning an embodiment of the present invention. FIG. 4 is a diagram illustrating an example of a relationship between an origin position of a ram and an origin position of a mechanical angle when the servomotor according to the embodiment of the present invention is mounted. FIG. 7 is a diagram illustrating an example of an operation of the photointerrupter according to the embodiment of the present invention.

(Embodiment)
(Configuration of servo press device)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating an example of a configuration of a servo press device 1 according to the present embodiment. The servo press device 1 includes a servo motor 2, a resolver 3, a press mechanism 20, and a servo motor driver 30.

  The servo motor 2 has a rotating shaft (not shown), and operates the press mechanism 20 by rotating the rotating shaft. The rotation of the rotation shaft of the servo motor 2 is controlled by a drive current supplied from the servo motor driver 30.

The resolver 3 is installed on the servo motor 2. The resolver 3 outputs an angle signal for three cycles per one rotation of the rotation shaft of the servomotor 2 as an electrical angle. Further, the resolver 3 detects the number of rotations of the electrical angle. Here, the electrical angle rotation number is a number indicating the period of the electrical angle output by the resolver 3.
The resolver 3 supplies a resolver signal to the servo motor driver 30. Here, the resolver signal is a signal indicating the detected electrical angle and electrical angle rotation speed.

The press mechanism 20 is operated by the servo motor 2. The press mechanism 20 includes a belt 4, a drive pulley 5, a driven pulley 6, a ball screw 7, a ram 8, a position indicating bar 9, a photo interrupter 10, and a seat surface 11.
A driven pulley 6 is attached to one end of the ball screw 7. The belt 4 is wound around the driven pulley 6 and the driving pulley 5. The drive pulley 5 is fixed to the output shaft of the servomotor 2, and the rotation of the servomotor 2 causes the ball screw 7 to which the driven pulley 6 is attached to rotate from the drive pulley 5 via the belt 4.

  The ram 8 is screwed into the ball screw 7. As the ball screw 7 rotates, the ram 8 moves up and down linearly. Here, the ball screw 7 is rotated by the rotation of the rotation shaft of the servomotor 2. Therefore, the ram 8 is driven by the rotation of the rotation shaft of the servo motor 2. When the servo motor 2 is driven to rotate, the ram 8 moves vertically and linearly to generate a press load.

The position indicating bar 9 is installed on the ram 8 and indicates the vertical position of the ram 8 to the photo interrupter 10.
The photo interrupter 10 is installed on the seating surface 11 and detects an origin position of the ram 8. A method by which the photo interrupter 10 detects the origin position of the ram 8 will be described later.

  The servo motor driver 30 supplies a drive current to the servo motor 2 based on a drive command signal supplied by the computer PC.

Here, the configuration of the servo motor driver 30 will be described with reference to FIG.
FIG. 2 is a diagram illustrating an example of a configuration of the servo motor driver 30 according to the present embodiment. The servo motor driver 30 includes a drive signal generation unit 31, a drive unit 32, a rotation angle detection unit 33, a storage control unit 34, a storage unit 35, and a rotation frequency data setting unit 36.

  The drive signal generation unit 31 generates a drive signal for driving the servo motor 2 and supplies the drive signal to the drive unit 32. Here, the drive signal generator 31 generates a drive signal based on a drive command signal supplied from the computer PC and a rotation angle signal supplied from the rotation angle detector 33. The rotation angle signal is a signal indicating the mechanical angle of the rotation axis of the servo motor 2. The drive signal generation section 31 generates a drive signal by correcting a signal generated from the drive command signal based on the rotation angle signal.

  The drive unit 32 generates a drive current based on the drive signal supplied from the drive signal generation unit 31. The drive unit 32 supplies the generated drive current to the servo motor 2. The drive unit 32 drives the servomotor 2 by supplying a drive current to the servomotor 2.

The rotation angle detection unit 33 detects the mechanical angle of the rotation axis of the servomotor 2 and supplies a rotation angle signal indicating the detected mechanical angle to the drive signal generation unit 31.
The rotation angle detection unit 33 acquires a resolver signal from the resolver 3. The rotation angle detector 33 generates electrical angle data 350 from the electrical angle indicated by the obtained resolver signal. The rotation angle detection unit 33 generates multi-rotation data 351 from the electrical angle rotation number indicated by the acquired resolver signal. The rotation angle detection unit 33 causes the storage unit 35 to store the generated electrical angle data 350 and the multi-rotation data 351 via the storage control unit 34.

  Here, the electrical angle data 350 is data indicating an electrical angle. The electric angle corresponds to an angle from a reference angle in one rotation of the rotation shaft of the servomotor 2. Here, the reference angle is, for example, 0 degree. Therefore, the electrical angle data 350 is data indicating an angle from a reference angle in one rotation of the rotation shaft of the servomotor 2.

  The multi-rotation data 351 is data indicating the number of rotations RN of the rotation shaft of the servo motor 2 when the electrical angle is used as a unit. That is, the multi-rotation data 351 is data indicating the number of rotations RN from a reference number of times, which is a reference value of the number of rotations of the rotation axis of the servomotor 2. Here, the reference number of times is the number of rotations RN indicated by the multi-rotation data 351 when the multi-rotation data 351 is initialized. The number of rotations RN indicated by the multi-rotation data 351 when the multi-rotation data 351 is initialized may be set to an arbitrary number, for example, 0.

The rotation angle detection unit 33 acquires the electrical angle data 350 and the multi-rotation data 351 from the storage unit 35 via the storage control unit 34. The rotation angle detection unit 33 detects the mechanical angle of the rotation axis of the servo motor 2 based on the electric angle indicated by the obtained electric angle data 350 and the electric angle rotation speed indicated by the obtained multi-rotation data 351.
Accordingly, the rotation angle detection unit 33 calculates the rotation angle (mechanical angle) of the rotation axis of the servo motor 2 from the electrical angle data 350 indicating the angle from the reference angle in one rotation of the rotation axis of the servo motor 2, and the servo angle. Detection is performed based on the multi-rotation data 351 indicating the number of rotations RN from the reference number which is the reference value of the number of rotations of the rotation axis of the motor 2.

The storage control unit 34 controls the storage unit 35. For example, the storage control unit 34 causes the storage unit 35 to store the electrical angle data 350 and the multi-rotation data 351. Further, the storage control unit 34 acquires the electrical angle data 350 and the multi-rotation data 351 from the storage unit 35.
The storage unit 35 stores the electrical angle data 350 and the multi-rotation data 351 received from the storage control unit 34.

The rotation number data setting unit 36 initializes the multi-rotation data 351 in response to the photo interrupter 10 detecting the origin position of the ram 8. Here, the rotation number data setting unit 36 initializes the multi-rotation data 351 stored in the storage unit 35 via the storage control unit 34.
Accordingly, the rotation number data setting unit 36 sets the multi-rotation data 351 to the reference number in response to the photo interrupter 10 detecting the origin position of the ram 8.

(Origin movement)
With reference to FIG. 3, an origin setting operation of the servo press device 1 will be described.
FIG. 3 is a diagram illustrating an example of processing of an origin finding operation according to the present embodiment.
Step S100: Attach the servo motor 2 to the servo press device 1.
Referring now to FIG. 4, the relationship between the origin position of the ram 8 and the origin position of the mechanical angle when the servo motor 2 is mounted on the servo press device 1 will be described.

  FIG. 4 is a diagram illustrating an example of the relationship between the origin position of the ram 8 and the origin position of the mechanical angle when the servo motor 2 according to the present embodiment is mounted. Here, in the present embodiment, as an example, three rounds of the electrical angle correspond to one round of the mechanical angle. That is, when the phase of the drive current supplied to the servo motor 2 changes by three periods, the rotation shaft of the servo motor 2 makes one rotation.

The servo motor 2 is attached to the servo press device 1 such that the mechanical angle RO corresponding to the ram origin position is within the mechanical angle deviation amount E1.
The ram origin position correspondence mechanical angle RO is a mechanical angle corresponding to the origin position of the ram 8. That is, the mechanical angle RO corresponding to the ram origin position is the mechanical angle of the rotation axis of the servo motor 2 when the photo interrupter 10 detects the origin position of the ram 8.

The mechanical angle deviation amount E1 is an amount by which the mechanical angle of the rotating shaft of the servomotor 2 can deviate from the mechanical angle RO corresponding to the ram origin position. The mechanical angle blur amount E1 is smaller than the range of the angle of one electrical rotation of the electrical angle (mechanical angle 120 degrees). The angle of one electrical angle of rotation (mechanical angle of 120 degrees) is a division angle obtained by dividing the angle of one rotation of the rotation axis of the servo motor 2 (mechanical angle of 360 degrees).
The reason why the mechanical angle of the rotation axis of the servomotor 2 deviates from the mechanical angle RO corresponding to the ram origin position is that the members supporting the photointerrupter 10 and the position indicating bar 9 have low rigidity, and the origin of the servo press device 1 is reduced. This is because they vibrate.

  In the present embodiment, the servo motor 2 is mounted on the servo press device 1 such that the mechanical angle RO corresponding to the ram origin position coincides with the position corresponding to the position where the predetermined angle range is divided into two equal parts. Therefore, the servo motor 2 is mounted on the servo press device 1 so that the mechanical angle RO corresponding to the ram origin position falls within the range of plus or minus 60 degrees from the mechanical angle origin position.

  The servo motor 2 is attached to the servo press device 1 such that the predetermined angle range is set to a range of 10 degrees and the mechanical angle RO corresponding to the ram origin position falls within a range of plus or minus 5 degrees from the origin position of the mechanical angle. Is more preferable. When the mechanical angle RO corresponding to the ram origin position is mounted on the servo press device 1 such that the mechanical angle RO is within ± 5 degrees from the origin position of the mechanical angle, the displacement of the ram 8 is 20 micrometers.

  As described above, in the servo press device 1, the division angle (mechanical angle 120 degrees), which is the angle obtained by dividing the rotation angle of the rotation axis of the servo motor 2 by one rotation (mechanical angle 360 degrees), by one rotation. Represents the number of rotations RN of the rotary shaft of the servomotor 2 as a unit of. Further, in the servo press device 1, a position corresponding to a position where the division angle is equally divided in the reference number of times is the reference angle.

Returning to FIG. 3, description of the origin setting operation of the servo press device 1 will be continued.
Step S110: Raise the ram 8 until the photo interrupter 10 is turned on.
Here, the operation of the photo interrupter 10 will be described with reference to FIG.

  FIG. 5 is a diagram illustrating an example of the operation of the photointerrupter 10 according to the present embodiment. When the ram 8 is raised, the position indicating bar 9 attached to the ram 8 is raised. When the position indicating bar 9 moves up, the photo interrupter 10 and the position indicating bar 9 eventually intersect, and the light of the photo interrupter 10 is cut off. The photo interrupter 10 detects the origin position of the ram 8 by detecting that the light is blocked.

As described above, the servo motor 2 is attached to the servo press device 1 so that the mechanical angle RO corresponding to the ram origin position falls within the mechanical angle deviation amount E1.
Therefore, the photo interrupter 10 detects the origin position of the ram 8 based on the shake amount (mechanical angle shake amount E1) within one rotation of the number of rotations RN. Here, the number of rotations RN is the number of rotations of the rotating shaft of the servo motor 2 in the case where the electrical angle indicated by the multi-rotation data 351 is used as a unit. In the present embodiment, the electrical angle and the mechanical angle have, for example, a three-to-one relationship. When the rotation axis of the servomotor 2 makes one rotation in mechanical angle, the electrical angle makes three rotations. In the present embodiment in which the electrical angle and the mechanical angle are in a three-to-one relationship, the number of rotations RN is, for example, the number of times the rotation axis of the servo motor 2 rotates by one electrical angle (120 degrees). It is.

  Upon detecting the origin position of the ram 8, the photo interrupter 10 supplies an origin position detection signal to the number-of-rotations data setting unit 36 of the servo motor driver 30. Here, the origin position detection signal is a signal indicating that the origin position of the ram 8 has been detected.

Returning to FIG. 3, description of the origin setting operation of the servo press device 1 will be continued.
Step S120: Upon acquiring the origin position detection signal from the photo interrupter 10, the rotation number data setting unit 36 initializes the multi-rotation data 351 stored in the storage unit 35 via the storage control unit 34.

  When the multi-rotation data 351 is initialized, the rotation angle detection unit 33 acquires the electrical angle data 350 from the storage unit 35 via the storage control unit 34. Here, even if the multi-rotation data 351 is initialized, the electrical angle data 350 is not initialized. The rotation angle detection unit 33 supplies the obtained electrical angle data 350 to the drive signal generation unit 31.

  The drive signal generator 31 acquires the electrical angle data 350 from the rotation angle detector 33. The reference angle of the electrical angle and the origin position of the ram 8 are shifted by the electrical angle indicated by the electrical angle data 350. The drive signal generation unit 31 generates a drive signal using the reference angle (for example, 0 degree) of the electrical angle indicated by the acquired electrical angle data 350 as the origin position of the ram 8.

  Here, the multi-rotation data 351 is initialized, and the number of rotations RN indicated by the multi-rotation data 351 matches a reference number (for example, 0) which is a reference value of the number of rotations of the rotation axis of the servo motor 2. Therefore, the reference number, which is a reference value of the number of rotations of the rotary shaft of the servo motor 2, is a value indicating the origin position of the ram 8.

Step S130: The rotation number data setting unit 36 sets the resolver 3 to the incremental mode. When the resolver 3 is set to the incremental mode, the resolver 3 starts detecting the electrical angle rotation speed.

After step S130, the drive signal generator 31 generates a drive signal based on the drive command signal supplied from the computer PC and the rotation angle signal supplied by the rotation angle detector 33. Here, the mechanical angle indicated by the rotation angle signal is detected based on the electrical angle data 350 and the multi-rotation data 351. In addition, when the multi-rotation data 351 is initialized, the drive signal generation unit 31 generates a drive signal with the reference angle of the electrical angle indicated by the electrical angle data 350 as the origin position of the ram 8.
Accordingly, the drive signal generation unit 31 determines that the multi-rotation data 351 is based on the reference number of times based on the electrical angle data 350 used by the rotation angle detection unit 33 to detect the rotation angle of the rotation axis of the servomotor 2 and the multi-rotation data 351. The drive signal for controlling the drive unit 32 is generated by setting the reference angle of the electrical angle data 350 in the case of indicating the ram 8 as the reference position.

  Further, as described above, in the servo press device 1, the position corresponding to the position where the division angle is equally divided in the reference number of times is the reference angle. Therefore, the drive signal generation unit 31 generates a drive signal with the position corresponding to the position where the division angle is equally divided in the reference number of times set as the reference angle.

As described above, the servo press device 1 according to the present embodiment includes the servo motor 2, the drive unit 32, the ram 8, the rotation angle detection unit 33, the origin position detection unit (photo interrupter 10), A rotation frequency data setting unit 36 and a drive signal generation unit 31 are provided.
The servo motor 2 has a rotating shaft.
The drive section 32 drives the servo motor 2.
The rotation angle detection unit 33 calculates the rotation angle of the rotation axis of the servo motor 2 from angle data (electric angle data 350) indicating an angle from a reference angle in one rotation of the rotation axis of the servo motor 2, and the servo motor 2 And the number of rotations data (multi-rotation data 351) indicating the number of rotations RN from the reference number of times, which is the reference value of the number of rotations RN of the rotating shaft and the value indicating the origin position of the ram 8.
The origin position detection unit (photo interrupter 10) detects the origin position of the ram 8.
The number-of-rotations data setting unit 36 sets the number-of-rotations data (multi-rotation data 351) to the reference number in response to the origin position detecting unit (photo interrupter 10) detecting the origin position of the ram 8.
The drive signal generation unit 31 is configured to determine the rotation angle of the rotation axis of the servomotor 2 by the rotation angle detection unit 33 based on angle data (electrical angle data 350) and rotation number data (multi-rotation data 351). A drive signal for controlling the drive unit 32 is generated with the reference angle (for example, 0 degree) of the angle data (electrical angle data 350) when the number of rotations data (multi-rotation data 351) indicates the reference number as the reference position of the ram 8. I do.

  With this configuration, in the servo press device 1 according to the present embodiment, the reference angle (for example, 0 degree) of the angle data (electrical angle data 350) when the number of rotations data (multi-rotation data 351) indicates the reference number of times is set to the ram 8. Since the servo motor 2 can be driven at the reference position, the deviation of the origin position can be reduced each time the servo press device 1 determines the origin position.

  In the present embodiment, the servo motor 2 is driven by the servo press device 1 so that the origin position of the ram 8 falls within a shake amount (mechanical angle shake amount E1) within one rotation of the number of rotations RN of the rotary shaft of the servo motor 2. Has been described, but the servo motor 2 is adjusted so that the origin position of the ram 8 falls within the shake amount (mechanical angle shake amount E1) within one rotation of the number of rotations RN of the rotary shaft of the servo motor 2. Even if the servo press device 1 cannot be attached to the servo press device 1, the servo press device 1 according to the present embodiment uses angle data (electric angle data 350) when the number of rotations data (multi-rotation data 351) indicates a reference number of times. Since the servomotor 2 can be driven with the reference angle (for example, 0 degree) as the reference position of the ram 8, even if the rotation angle of the rotation axis of the servomotor 2 is larger than one rotation of the electrical angle, The displacement of the origin position can be reduced for each operation to determine the position of the origin of Bopuresu device 1.

  Here, the range larger than the range of one electrical angle rotation is, for example, a range of 60 degrees to 180 degrees or 180 degrees to 300 degrees of electrical angle. That is, in the servo press device 1 according to the present embodiment, the origin position of the servo press device 1 is determined in each range such as a range of 60 degrees to 180 degrees or a range of 180 degrees to 300 degrees in electrical angle. The deviation of the origin position for each operation can be reduced as compared with the case where the rotation number data (multi-rotation data 351) is not set to the reference number in response to the detection of the origin position of the ram 8.

Further, in the servo press device 1 according to the present embodiment, the origin position detection unit (photo interrupter 10) determines the origin position of the ram 8 by the amount of shake within one rotation of the number of rotations RN of the rotation axis of the servo motor 2 ( It is detected based on the mechanical angle blur amount E1).
With this configuration, in the servo press device 1 according to the present embodiment, the deviation of the origin position of the ram 8 is within the range of one rotation of the number of rotations RN of the rotating shaft of the servomotor 2 (mechanical angle deviation E1). Since the value falls within the range described below, the origin position can be kept within a predetermined range for each operation of determining the origin position of the servo press device.

Further, in the servo press device 1 according to the present embodiment, the number of rotations RN of the rotary shaft of the servomotor 2 is defined as a unit of one rotation obtained by dividing the rotation angle of the rotary shaft of the servomotor 2 by one rotation. Is represented.
With this configuration, in the servo press device 1 according to the present embodiment, the deviation of the origin position of the ram 8 can be kept within the range of the division angle for each operation of determining the origin position of the servo press device.

Further, in the servo press device 1 according to the present embodiment, the drive signal generation unit 31 generates a drive signal with a position corresponding to a position where the division angle is divided into two equal parts in the reference number of times as a reference angle.
With this configuration, in the servo press device 1 according to the present embodiment, each time the operation of determining the origin position of the servo press device is performed, the origin position is divided into two equal parts by dividing the range of the rotation angle of the rotation axis of the servo motor 2 at the reference number of times. Can be stored.

  In the above embodiment, the rotation angle of the rotation axis of the servomotor 2 detected by the rotation angle detection unit 33 is 0 degree in the range of ± 60 degrees, and is close to 0 degree of the electric angle detected by the resolver 3. The servo motor 2 is attached to the servo press device 1 so that the origin position detection unit (photo interrupter 10) is turned on. Therefore, when the origin position detecting unit (photo interrupter 10) is turned on, the number of rotations data (multi-rotation data 351) is initialized, so that the servo motor 2 is determined for each operation of determining the origin position of the servo press device. The origin position of the rotation angle of the rotation axis can be within a range of ± 60 degrees.

  Here, when the influence of the chattering of the origin position detection unit (photo interrupter 10) according to the present embodiment on the rotation angle of the rotation shaft of the servomotor 2 detected by the rotation angle detection unit 33 is calculated, expressed.

  Here, the pitch p is the pitch of the ball screw 7. The vibration amplitude dp is the vibration amplitude of the origin position detection unit (photo interrupter 10). The number of teeth wb is the number of teeth of the driven pulley 6. The number of teeth wm is the number of teeth of the driving pulley 5.

  According to Expression (1), in the present embodiment, the rotation angle θ of the rotation shaft of the servo motor 2 is 25.2 degrees. Therefore, when the origin position detecting unit (photo interrupter 10) and the position indicating bar 9 deviate by 0.1 mm, the rotation angle of the rotation axis of the servo motor 2 detected by the rotation angle detecting unit 33 is deviated by 25.2 degrees. I will.

In the servo press device 1 according to the present embodiment, the rotation angle of the rotation shaft of the servo motor 2 detected by the rotation angle detection unit 33 falls within the range of plus or minus 60 degrees for each operation of determining the origin position of the servo press device. . Since the rotation angle of the rotation axis of the servo motor 2 falls within the range of plus or minus 60 degrees for each operation of determining the origin position of the servo press device, the origin position detection unit (photo interrupter) is used in the servo press device 1 according to the present embodiment. Even if an error in the rotation angle occurs within the range of plus or minus 60 degrees (for example, 25.2 degrees) due to chattering or vibration in 10), 0 degree which is the reference angle of the rotation angle is set as the origin position of the ram 8. The servo motor 2 is driven. Since the servo motor 2 is driven with the reference angle of the rotation angle of 0 degrees as the origin position of the ram 8, the rotation angle detection unit 33 detects an error due to chattering or vibration in the servo press device 1 according to the present embodiment. It does not affect the rotation angle of the rotation shaft of the servo motor 2.
Therefore, in the servo press device 1 according to the present embodiment, the detection error of the rotation angle of the rotation axis of the servomotor 2 is smaller than that in the conventional method in which the position where the photo interrupter is turned on is the origin position. , And a wide initialization range.

  In the above-described embodiment, the case where the rotation angle detection unit 33 calculates the rotation angle of the rotation shaft of the servo motor 2 based on the resolver signal supplied from the resolver is described. The rotation angle detection unit 33 may calculate the rotation angle of the rotation shaft of the servo motor 2 based on an electric angle supplied from an absolute angle sensor such as an incremental encoder and a signal indicating the electric angle rotation speed.

  As described above, one embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like can be made without departing from the gist of the present invention. It is possible to

DESCRIPTION OF SYMBOLS 1 ... Servo press apparatus, 2 ... Servo motor, 3 ... Resolver, 4 ... Belt, 5 ... Drive pulley, 6 ... Followed pulley, 7 ... Ball screw, 8 ... Ram, 9 ... Position indication bar, 10 ... Photo interrupter, 11 ... Seat surface, 20 ... Press mechanism, 30 ... Servo motor driver, PC ... Computer, 31 ... Drive signal generation unit, 32 ... Drive unit, 33 ... Rotation angle detection unit, 34 ... Storage control unit 34, 35 ... Storage unit, 350: electrical angle data, 351: multi-rotation data, 36: rotation number data setting unit

Claims (5)

A servomotor having a rotation axis;
A drive unit for driving the servo motor,
A ram driven by rotation of the rotating shaft;
The rotation angle of the rotation shaft is an angle data indicating an angle from a reference angle of one rotation of the rotation shaft, and a reference value of the number of rotations of the rotation shaft, and a value indicating an origin position of the ram. A rotation angle detection unit that detects by rotation number data indicating the number of rotations from the reference number,
An origin position detection unit for detecting the origin position,
In response to the origin position detecting unit detecting the origin position, the number of rotations data, the number of rotations data setting unit to set the reference number of times,
The angle data used by the rotation angle detection unit to detect the rotation angle of the rotation axis, based on the number of rotation data, the reference angle of the angle data when the number of rotation data indicates the reference number of times A drive signal generation unit that generates a drive signal for controlling the drive unit at a reference position of the ram. 2. The servo press device according to claim 1, wherein the origin position detection unit detects the origin position based on a shake amount within a range of one rotation of the number of rotations. 3. 3. The servo press device according to claim 1, wherein the number of rotations is expressed by using a division angle obtained by dividing an angle of one rotation of the rotation angle as a unit of one rotation. 4. 4. The servo press device according to claim 3, wherein the drive signal generating unit generates the drive signal by setting a position corresponding to a position at which the division angle is equally divided in the reference number of times as the reference angle. 5. A servomotor having a rotation axis;
A drive unit for driving the servo motor,
A ram driven by rotation of the rotating shaft;
The rotation angle of the rotation shaft is an angle data indicating an angle from a reference angle of one rotation of the rotation shaft, and a reference value of the number of rotations of the rotation shaft, and a value indicating an origin position of the ram. A rotation angle detection unit that detects by rotation number data indicating the number of rotations from the reference number,
A control method for a servo press device comprising:
An origin position detecting step of detecting the origin position,
In response to the origin position being detected in the origin position detecting step, the number of rotations data, the number of rotations data setting step of setting the reference number of times,
The angle data used by the rotation angle detection unit to detect the rotation angle of the rotation axis, based on the number of rotation data, the reference angle of the angle data when the number of rotation data indicates the reference number of times A drive signal generation unit that generates a drive signal for controlling the drive unit at a reference position of the ram.

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