JP2012205841A - Sewing machine and sewing machine control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sewing machine and a sewing machine control method which, when a main shaft and a cloth feeding mechanism are driven by separate motors, can maintain synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism even when sewing speed is changed.SOLUTION: The sewing machine comprises: a main motor for driving a main shaft for vertically moving a sewing needle; and a cloth feeding motor for driving a cloth feeding mechanism for feeding cloth. The sewing machine control method comprises the following steps of: acquiring rotation angles of output shafts of the main motor and the cloth feeding motor (S11 and S13); setting, from the rotation angle of the main motor, a target rotation angle at which the output shaft of the cloth feeding motor is to be positioned in accordance with the rotation angle of the main motor (S14); calculating a deviation between the set target rotation angle and an actual rotation angle of the cloth feeding motor (S15); and calculating, based on the calculated deviation, a rotation speed at which the cloth feeding motor is instructed to rotate (S16).

Description

  The present invention relates to a sewing machine that drives a main shaft and a cloth feed mechanism with separate motors, and a control method for the sewing machine.

  There is a sewing machine in which the main shaft and the cloth feed mechanism are driven by different motors. Since the sewing machine can freely control the cloth feed amount, various patterns can be easily sewn. The sewing machine needs to keep the driving of the main shaft and the cloth feeding mechanism synchronized. The sewing machine disclosed in Patent Document 1 determines the timing for starting cloth feeding based on the rotation speed and rotation phase of the main shaft. Further, the sewing machine corrects the timing at which the cloth feed is started based on the cloth feed amount and the acceleration of the spindle. Therefore, the cloth feed starts at an appropriate timing and ends by the time when the sewing needle comes in contact with the cloth.

JP-A-5-228276

  In the conventional sewing machine, the timing for starting the cloth feed changes according to the cloth feed amount and the acceleration of the spindle. In the conventional sewing machine, the time (feed time) required for the cloth feed is determined according to the cloth feed amount. Therefore, when the operator operates the pedal or the like to change the rotation speed of the main spindle during the cloth feed operation, the speed of the cloth feed cannot follow the change in the rotation speed of the main spindle and the drive of the main spindle and the cloth feed mechanism Out of sync. If the driving of the main shaft and the driving of the cloth feed mechanism are out of synchronization, the quality of sewing deteriorates.

  An object of the present invention is to provide a sewing machine and a sewing machine control method capable of maintaining the synchronization of the driving of the main shaft and the driving of the cloth feeding mechanism even when the sewing speed is changed when the main shaft and the cloth feeding mechanism are driven by different motors. Is to provide.

  The sewing machine according to the first aspect of the present invention is a sewing machine including a main motor that drives a main shaft that moves a sewing needle up and down and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth. A main rotation angle detection unit that detects a main rotation angle that is an angle, a main rotation angle acquisition unit that acquires a detection result of the main rotation angle detected by the main rotation angle detection unit, and an output shaft of the cloth feed motor A cloth feed rotation angle detector that detects a cloth feed rotation angle that is a rotation angle; a cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detector; A cloth feed target angle setting unit for setting a target rotation angle at which the output shaft of the cloth feed motor should be positioned corresponding to an angle from the main rotation angle acquired by the main rotation angle acquisition unit; and the cloth feed target angle The target rotation angle set by the setting unit and the cloth feed A cloth feed deviation calculating section that calculates a deviation of the cloth feed rotation angle acquired by the roll angle acquiring section; and a first rotation speed calculating section that calculates a rotation speed instructed to the cloth feed motor based on the deviation. Prepare.

  The sewing machine of the first aspect sets a target rotation angle at which the output shaft of the cloth feed motor should be positioned from the rotation angle (main rotation angle) of the main motor. The sewing machine calculates a deviation between the set target rotation angle and the actual rotation angle of the cloth feed motor. The sewing machine calculates the rotation speed of the cloth feed motor based on the calculated deviation. Even when the rotation speed of the main shaft changes, the cloth feed motor rotates in synchronization with the main motor. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism. In particular, the sewing machine can properly keep the cloth feed motor and the main motor synchronized even when the main motor is stopped or when the operator manually rotates the main shaft.

  The sewing machine according to the second aspect of the present invention is a sewing machine including a main motor that drives a main shaft that moves the sewing needle up and down and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth. A main rotation angle detection unit that detects a main rotation angle that is an angle, a main rotation angle acquisition unit that acquires a detection result of the main rotation angle detected by the main rotation angle detection unit, and an output shaft of the cloth feed motor A cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle; a cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit; A main target angle setting unit that sets a target rotation angle at which the output shaft of the main motor should be positioned corresponding to a rotation angle from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit, and the main target angle The target rotation angle set by the setting unit and the main rotation angle Comprising a main deviation calculating section for calculating a deviation of said main rotation angle rotation angle acquiring unit has acquired, on the basis of the deviation, and a first rotation speed calculation unit that calculates a rotation speed instructing the cloth feed motor.

  The sewing machine of the second aspect sets a target rotation angle at which the output shaft of the main motor should be positioned from the rotation angle of the cloth feed motor (cloth feed rotation angle). The sewing machine calculates a deviation between the set target rotation angle and the actual rotation angle of the main motor. The sewing machine calculates the rotation speed of the cloth feed motor based on the calculated deviation. Even when the rotation speed of the main shaft changes, the cloth feed motor rotates in synchronization with the main motor. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism. In particular, the sewing machine can properly keep the cloth feed motor and the main motor synchronized even when the main motor is stopped or when the operator manually rotates the main shaft.

  A sewing machine according to a third aspect of the present invention is a sewing machine including a main motor that drives a main shaft that moves a sewing needle up and down and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth. A main rotation angle detection unit that detects a main rotation angle that is an angle, a main rotation angle acquisition unit that acquires a detection result of the main rotation angle detected by the main rotation angle detection unit, and the cloth feed mechanism that A terminal angle acquisition unit that acquires a terminal angle that is a main rotation angle at which the output shaft of the main motor should be positioned when reaching the terminal position, the terminal angle acquired by the terminal angle acquisition unit, and the main rotation angle acquisition A main rotation angle remaining amount calculation unit that calculates a remaining rotation angle until the output shaft of the main motor reaches the terminal angle based on the main rotation angle acquired by the unit, and a rotation speed of the main motor Get speed to get main rotation speed And the time required for the output shaft of the main motor to reach the terminal angle based on the remaining rotation angle calculated by the main rotation angle remaining amount calculation unit and the main rotation speed acquired by the speed acquisition unit. A time calculation unit that calculates the cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of the output shaft of the cloth feed motor, and the cloth feed rotation angle detected by the cloth feed rotation angle detection unit The cloth feed rotation angle acquisition unit for acquiring the detection result of the cloth feed, and the cloth feed motor from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit until the cloth feed mechanism reaches the end position of the cloth feed The remaining rotation angle calculated by the cloth feed rotation angle remaining amount calculation unit and the remaining rotation angle calculated by the time calculation unit at the required time calculated by the time calculation unit. The rotation speed necessary for the And a second rotation speed calculation unit for output.

  The sewing machine of the third aspect calculates the time required for the output shaft of the main motor to reach the terminal angle. The remaining rotation angle of the cloth feed motor until the cloth feed mechanism reaches the cloth feed end position is calculated. The sewing machine calculates the rotation speed for the cloth feed motor to rotate the remaining rotation angle in the calculated required time. As a result, the cloth feed motor is synchronized with the main motor, and the time when the cloth feed mechanism reaches the end position coincides with the time when the output shaft of the main motor reaches the end angle. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism. In particular, even when the speed of the main shaft is increasing, the sewing machine can accurately keep the two motors synchronized.

  The sewing machine according to the first aspect and the second aspect includes a terminal angle acquisition unit that acquires a terminal angle that is a main rotation angle at which the output shaft of the main motor should be positioned when the cloth feed mechanism reaches a cloth feed terminal position. The remaining rotation angle until the output shaft of the main motor reaches the terminal angle is calculated based on the terminal angle acquired by the terminal angle acquisition unit and the main rotation angle acquired by the main rotation angle acquisition unit. A main rotation angle remaining amount calculation unit, a speed acquisition unit that acquires a main rotation speed that is a rotation speed of the main motor, the remaining rotation angle calculated by the main rotation angle remaining amount calculation unit, and the speed acquisition unit Based on the rotation speed acquired by the time calculation unit for calculating a time required for the output shaft of the main motor to reach the terminal angle, and the cloth feed rotation angle acquired by the fabric feed rotation angle acquisition unit. From the above, the cloth feed mechanism Calculating the remaining rotation angle of the cloth feed motor until the terminal position is reached, and calculating the time of the remaining rotation angle calculated by the cloth feed rotation angle remaining amount calculation unit. A second rotation speed calculation unit that calculates a rotation speed necessary for the cloth feed motor to rotate in the required time calculated by the unit, and whether the main rotation speed acquired by the speed acquisition unit is equal to or less than a threshold value. A determination unit that determines whether the main rotation speed is equal to or less than the threshold value, and when the determination unit determines that the main rotation speed is equal to or less than the threshold value, the cloth feeding motor is driven at a rotation speed calculated by the first rotation speed calculation unit. A high-speed drive that drives the cloth feed motor based on at least the rotation speed calculated by the second rotation speed calculation unit when the determination unit determines that the main rotation speed is greater than the threshold value. And further comprising It may be.

  The sewing machine can calculate the rotation speed (first speed) of the cloth feed motor according to the rotation angle at which the output shaft of the motor should be positioned and the deviation between the rotation angle at which the output shaft is actually positioned. Further, the sewing machine can calculate the rotation speed (second speed) of the cloth feed motor based on the rotation speed of the main motor. According to the first speed, the sewing machine can appropriately keep the cloth feed motor and the main motor synchronized even when the main motor is stopped or when the operator manually rotates the main shaft. Considering the second speed, the sewing machine can accurately keep the two motors synchronized even when the speed of the spindle is increased. The sewing machine can drive the cloth feed mechanism more appropriately by changing the control method of the cloth feed motor according to the rotation speed of the main motor.

  The sewing machine calculates a rotation speed for driving the cloth feed motor at a specific ratio from the rotation speed calculated by the first rotation speed calculation unit and the rotation speed calculated by the second rotation speed calculation unit. A three rotation speed calculation unit may be further provided. The third rotation speed calculation unit may calculate a rotation speed for driving the cloth feed motor by changing the specific ratio according to the main rotation speed. The high-speed drive unit may drive the cloth feed motor at the rotation speed calculated by the third rotation speed calculation unit when the determination unit determines that the main rotation speed is greater than the threshold value. . The sewing machine can calculate the rotational speed of the cloth feed motor by changing the ratio of the first speed suitable for low speed and the second speed suitable for high speed according to the main rotational speed. Therefore, the cloth feed motor can be driven at a rotation speed more suitable for the main rotation speed of the main motor.

  The sewing machine of the 1st thru / or the 3rd mode may be provided with the setting part which can set up the end position and the end angle of cloth feed in the cloth feed mechanism. The operator can freely set the cloth feed amount. The sewing machine can drive the cloth feed motor at an appropriate speed according to the set value of the cloth feed amount.

  A sewing machine according to a fourth aspect of the present invention is a sewing machine including a main motor that drives a main shaft that moves a sewing needle up and down, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth. A main rotation angle detection unit that detects a main rotation angle that is an angle, a main rotation angle acquisition unit that acquires a detection result of the main rotation angle detected by the main rotation angle detection unit, and an output shaft of the cloth feed motor A cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle; a cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit; A main target angle setting unit that sets a target rotation angle at which the output shaft of the main motor should be positioned corresponding to a rotation angle from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit, and the main target angle The target rotation angle set by the setting unit and the main rotation angle Comprising a main deviation calculating section for calculating a deviation of said main rotation angle rotation angle acquiring unit has acquired, on the basis of the deviation, and a main rotation speed calculation unit that calculates a rotation speed instructing the main motor.

  The sewing machine of the fourth aspect sets a target rotation angle at which the output shaft of the main motor should be positioned from the rotation angle of the cloth feed motor (cloth feed rotation angle). The sewing machine calculates a deviation between the set target rotation angle and the actual rotation angle of the main motor. The sewing machine calculates the rotation speed of the main motor based on the calculated deviation. Even when the driving speed of the cloth feed mechanism changes, the main motor rotates in synchronization with the cloth feed motor. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism.

  A control method for a sewing machine according to a fifth aspect of the present invention includes a main motor that drives a main shaft that moves a sewing needle up and down, a main rotation angle detection unit that detects a main rotation angle that is a rotation angle of an output shaft of the main motor, Control of a sewing machine executed by a sewing machine including a cloth feed motor that drives a cloth feed mechanism that feeds the cloth, and a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor. In the method, a main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector, and a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detector A cloth feed target that sets a target rotation angle at which the output shaft of the cloth feed motor should be positioned corresponding to the main rotation angle from the main rotation angle acquired in the main rotation angle acquisition step. Corner setting step; Based on the deviation, the target rotation angle set in the cloth feed target angle setting step, the cloth feed deviation calculation step for calculating the deviation of the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step, A first rotation speed calculation step of calculating a rotation speed instructed to the cloth feed motor.

  According to the fifth aspect of the sewing machine control method, even when the rotation speed of the main shaft changes, the cloth feed motor rotates in synchronization with the main motor. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism. In particular, the sewing machine can properly keep the cloth feed motor and the main motor synchronized even when the main motor is stopped or when the operator manually rotates the main shaft.

  A control method for a sewing machine according to a sixth aspect of the present invention includes a main motor that drives a main shaft that moves the sewing needle up and down, a main rotation angle detection unit that detects a main rotation angle that is the rotation angle of the output shaft of the main motor, Control of a sewing machine executed by a sewing machine including a cloth feed motor that drives a cloth feed mechanism that feeds the cloth, and a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor. In the method, a main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector, and a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detector A main feed rotation angle acquisition step and a target rotation angle at which the output shaft of the main motor should be positioned corresponding to the cloth feed rotation angle is set from the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step. Target angle setting step Based on the deviation, the target rotation angle set in the main target angle setting step, a main deviation calculation step for calculating a deviation of the main rotation angle acquired in the main rotation angle acquisition step, and the cloth A first rotation speed calculation step of calculating a rotation speed instructed to the feed motor.

  According to the control method for the sewing machine of the sixth aspect, even when the rotational speed of the main shaft changes, the cloth feed motor rotates in synchronization with the main motor. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism. In particular, the sewing machine can properly keep the cloth feed motor and the main motor synchronized even when the main motor is stopped or when the operator manually rotates the main shaft.

  A control method for a sewing machine according to a seventh aspect of the present invention includes a main motor that drives a main shaft that moves a sewing needle up and down, a main rotation angle detection unit that detects a main rotation angle that is a rotation angle of an output shaft of the main motor, Control of a sewing machine executed by a sewing machine including a cloth feed motor that drives a cloth feed mechanism that feeds the cloth, and a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor. In the method, a main rotation angle acquisition step for acquiring a detection result of the main rotation angle detected by the main rotation angle detector, and an output shaft of the main motor at the time when the cloth feed mechanism reaches a cloth feed end position. Based on the terminal angle acquisition step of acquiring the terminal angle that is the main rotation angle to be positioned, the terminal angle acquired in the terminal angle acquisition step, and the main rotation angle acquired in the main rotation angle acquisition step, The main A main rotation angle remaining amount calculation step for calculating a remaining rotation angle until the output shaft of the motor reaches the terminal angle, a speed acquisition step for acquiring a main rotation speed that is a rotation speed of the main motor, and the main rotation Time for calculating the time required for the output shaft of the main motor to reach the terminal angle based on the remaining rotation angle calculated in the remaining angle calculation step and the main rotation speed acquired in the speed acquisition step From the calculation step, the cloth feed rotation angle acquisition step for acquiring the detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detector, and the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step, A cloth feed rotation angle remaining amount calculating step for calculating a remaining rotation angle of the cloth feed motor until the cloth feed mechanism reaches the cloth feed end position; and a cloth feed rotation angle remaining amount calculating step. The remaining rotation angle calculated in flop, and a second rotation speed calculation step of the cloth feed motor in the required time calculated by the time calculating step calculates a rotation speed required to rotate.

  According to the sewing machine control method of the seventh aspect, the cloth feed motor is synchronized with the main motor, and the time when the cloth feed mechanism reaches the end position coincides with the time when the output shaft of the main motor reaches the end angle. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism. In particular, the sewing machine can accurately keep the synchronization of the two motors even when the speed of the main shaft is increasing.

  A control method for a sewing machine according to an eighth aspect of the present invention includes a main motor that drives a main shaft that moves a sewing needle up and down, a main rotation angle detection unit that detects a main rotation angle that is the rotation angle of the output shaft of the main motor, Control of a sewing machine executed by a sewing machine including a cloth feed motor that drives a cloth feed mechanism that feeds the cloth, and a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor. In the method, a main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector, and a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detector A main feed rotation angle acquisition step and a target rotation angle at which the output shaft of the main motor should be positioned corresponding to the cloth feed rotation angle is set from the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step. Target angle setting step Based on the deviation, the target rotation angle set in the main target angle setting step, the main deviation calculation step for calculating the deviation of the main rotation angle acquired in the main rotation angle acquisition step, and the main A main rotational speed calculating step for calculating a rotational speed instructed to the motor.

  According to the control method for the sewing machine of the eighth aspect, even when the driving speed of the cloth feed mechanism changes, the main motor rotates while maintaining synchronization with the cloth feed motor. Therefore, even if the sewing speed changes, the sewing machine can maintain the synchronization between the driving of the main shaft and the driving of the cloth feeding mechanism.

The perspective view of the sewing machine 1. FIG. FIG. 3 is an enlarged perspective view in the vicinity of a sewing needle 8 and a needle plate 15. The left view of the cloth feed mechanism 32. FIG. FIG. 2 is a block diagram showing an electrical configuration of the sewing machine 1. 6 is a flowchart of a cloth feed amount setting process executed by the sewing machine 1; The flowchart of the 1st speed control process which the sewing machine 1 of 1st embodiment performs. 6 is a flowchart of an operation confirmation process executed by the sewing machine 1; The flowchart of the 2nd speed control process which the sewing machine 1 of 2nd embodiment performs. The flowchart of the 3rd speed control process which the sewing machine 1 of 3rd embodiment performs. The flowchart of the 4th speed control process which the sewing machine 1 of 4th embodiment performs. The flowchart of the 5th speed control processing which the sewing machine 1 of 5th embodiment performs.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. The configuration of the sewing machine 1 will be described with reference to FIGS. The upper side, lower side, right side, left side, front side, and rear side of FIG. 1 are the upper side, lower side, right side, left side, front side, and rear side of the sewing machine 1, respectively.

  The sewing machine 1 includes a bed 2, a pedestal 3, and an arm 4. The bed part 2 is a foundation of the sewing machine 1. The bed 2 is fitted into a recess (not shown) on the upper surface of the table 20 from above and the sewing machine 1 is mounted on the table 20. The pedestal 3 extends vertically upward from the right end of the bed 2. The arm portion 4 extends leftward from the upper end of the pedestal column portion 3. The arm part 4 faces the upper surface of the bed part 2. The arm portion 4 is provided with a presser foot 17 below the left end portion. The arm portion 4 holds a needle bar 7 therein. The needle bar 7 has a sewing needle 8 (see FIGS. 2 and 3) attached to the lower end. The needle bar 7 and the sewing needle 8 reciprocate up and down as the main motor 13 is driven. The arm portion 4 includes a balance 9 in front of the left end portion. The balance 9 moves up and down according to the needle bar 7. The arm part 4 fixes the operation part 10 to the upper surface. The operation unit 10 includes a liquid crystal panel 11 on the front surface. The operator operates the operation unit 10 while looking at the liquid crystal panel 11 and inputs various instructions to the sewing machine 1.

  The sewing machine 1 includes a control device 30 on the lower surface of the table 20. The control device 30 is connected to a stepping pedal 22 via a rod 21. The operator operates the pedal 22 to the toe side or the heel side. The control device 30 controls the operation of the sewing machine 1 according to the operation direction and operation amount of the pedal 22.

  The pedestal 3 has a main motor 13 at the upper right side. The arm portion 4 includes a main shaft 14 inside. The main shaft 14 extends in the left-right direction inside the arm portion 4 in a rotatable state. The right end of the main shaft 14 is connected to the main motor 13. The left end of the main shaft 14 is connected to a needle bar vertical movement mechanism (not shown). The main motor 13 drives the main shaft 14 to move the needle bar 7 and the balance 9 up and down. Although details will be described later, in the sewing machine 1 of the present embodiment, the main motor 13 also moves the cloth feed mechanism 32 (see FIG. 3) up and down.

  As shown in FIG. 2, the bed portion 2 includes a needle plate 15 at the upper left end. The needle plate 15 has a needle hole 18 in a substantially central portion. The lower end of the sewing needle 8 passes through the needle hole 18 when lowered. The needle plate 15 includes a feed dog hole 19 on each of the left side, the rear side, and the right side of the needle hole 18. The feed dog hole 19 is a rectangular hole that is long in the front-rear direction. The bed portion 2 includes a shuttle mechanism (not shown) and a cloth feed mechanism 32 (see FIG. 3) below the needle plate 15.

  As shown in FIG. 3, the cloth feed mechanism 32 includes a feed base 33, a feed dog 34, a swing link 36, an intermediate link 38, and a connection link 39. The feed base 33 is disposed below the needle plate 15 in a state parallel to the needle plate 15. The feed base 33 fixes three feed dogs 34 (only one feed dog 34 is shown in FIG. 3) on the upper surface. Each of the feed dogs 34 corresponds to the position of the feed dog hole 19. Each of the feed dogs 34 is long in the front-rear direction (left-right direction in FIG. 3). The feed dog 34 is provided with projections and depressions on the top for firmly sandwiching the cloth.

  The front end portion of the feed base 33 is connected to one end of the swing link 36 so as to be swingable. The center of the swing link 36 is rotatably supported by a support shaft 37 extending in the left-right direction. The other end of the swing link 36 is connected to the intermediate link 38. The output shaft 24 of the cloth feed motor 23 is connected to the connection link 39. The intermediate link 38 connects the swing link 36 and the connection link 39. When the cloth feed motor 23 rotates, the power of the cloth feed motor 23 is transmitted in the order of the connecting link 39, the intermediate link 38, and the swing link 36. The swing link 36 rotates around the support shaft 37. The feed base 33 swings as the swing link 36 rotates. Therefore, the feed base 33 moves in the front-rear direction by the power of the cloth feed motor 23.

  The feed base 33 includes a bifurcated portion 35 at the rear. The bifurcated portion 35 extends slightly forward from the rear end of the feed base 33 and bends backward. The bifurcated portion 35 sandwiches the vertical feed cam 40 with the rear end portion of the feed base 33. The vertical feed cam 40 is an eccentric cam rotated by a drive shaft 41. When the drive shaft 41 rotates, the vertical feed cam 40 rotates and the feed base 33 moves up and down. In the sewing machine 1 of the present embodiment, the drive shaft 41 is connected to a transmission mechanism (not shown). The transmission mechanism is connected to the main shaft 14 (see FIG. 1). The rotation of the main shaft 14 is transmitted to the drive shaft 41 via the transmission mechanism. The rotation of the drive shaft 41 and the rotation of the main shaft 14 are synchronized. While the needle bar 7 and the sewing needle 8 reciprocate up and down once, the feed base 33 and the feed dog 34 reciprocate up and down once. That is, in this embodiment, the vertical movement of the sewing needle 8 and the vertical movement of the feed dog 34 are mechanically synchronized.

  When the feed base 33 rises, the feed dog 34 protrudes above the needle plate 15 from the feed dog hole 19, and the cloth 29 is sandwiched between the presser foot 17. If the cloth 29 is equal to or less than a predetermined thickness, the sewing needle 8 does not pierce the cloth 29 while the feed dog 34 is positioned above the needle plate 15. During the execution of sewing, the sewing machine 1 monitors the rotation angle phases of the main motor 13 and the cloth feed motor 23. Although details will be described later, the sewing machine 1 synchronizes the main motor 13 and the cloth feed motor 23, and while the feed dog 34 is positioned above the needle plate 15, the cloth feed is performed by the amount specified by the sewing program. The motor 23 is driven. Therefore, the cloth 29 moves in the front-rear direction in a state where the sewing needle 8 is not pierced. When the feed base 33 is lowered, the feed dog 34 is positioned below the needle plate 15. If the feed dog 34 is positioned below the needle plate 15, the cloth 29 will not move even if the feed dog 34 moves in the front-rear direction. The sewing needle 8 forms a seam on the cloth 29 while the feed dog 34 is positioned below the needle plate 15. As described above, the sewing machine 1 executes the driving of the cloth feed mechanism 32 in the horizontal direction (the front-rear direction in the present embodiment) and the driving of the needle bar 7 with different motors. Therefore, the sewing machine 1 can freely control the amount of horizontal movement of the feed dog 34 during sewing.

  The electrical configuration of the sewing machine 1 will be described with reference to FIG. The control device 30 of the sewing machine 1 includes a CPU 44. The CPU 44 controls the sewing machine 1. The CPU 44 is connected to a ROM 45, a RAM 46, an EEPROM (registered trademark) 47, and an I / O interface (hereinafter referred to as I / O) 48 via a bus. The ROM 45 stores a program for executing a cloth feed amount setting process (see FIG. 5), a speed control process (see FIGS. 6, 8, 9, 10, and 11), and an operation confirmation process (see FIG. 7), which will be described later. . The RAM 46 temporarily stores various values necessary for executing the program. The EEPROM 47 is a non-volatile storage device that stores various values.

  The I / O 48 is connected to the pedal 22 and the operation unit 10. The CPU 44 inputs an operation direction and an operation amount of the pedal 22. The CPU 44 inputs an operation instruction from the operator from the operation unit 10. The operator can set the cloth feed start position and the end position described later by operating the operation unit 10. The I / O 48 is connected to the drive circuits 51-53. The drive circuit 51 drives the liquid crystal panel 11. The drive circuit 52 drives the main motor 13 in accordance with a torque command signal input from the CPU 44. The sewing machine 1 includes a main encoder 55 for detecting a rotation angle phase and a rotation speed of the main motor 13. The main encoder 55 outputs the detection result of the rotation angle phase and rotation speed of the main motor 13 to the I / O 48. The drive circuit 53 drives the cloth feed motor 23 according to the cloth feed drive signal input from the CPU 44. The cloth feed motor 23 is a pulse motor. The cloth feed drive signal of the cloth feed motor 23 is a pulse signal. The sewing machine 1 includes a cloth feed encoder 56 for detecting the rotation angle phase and the rotation speed of the cloth feed motor 23. The cloth feed encoder 56 outputs the detection result of the rotation angle phase and the rotation speed of the cloth feed motor 23 to the I / O 48.

  With reference to FIGS. 5-7, the process which the sewing machine 1 of 1st embodiment performs is demonstrated. The CPU 44 of the sewing machine 1 executes the cloth feed amount setting process shown in FIG. 5, the first speed control process shown in FIG. 6, and the operation confirmation process shown in FIG. 7 according to the program stored in the ROM 45. The sewing machine 1 can execute the above three processes in parallel.

  The cloth feed setting process will be described with reference to FIG. In the cloth feed setting process, the sewing machine 1 sets the cloth feed start position and the end position of the cloth feed mechanism 32 (specifically, the feed dog 34) according to the operation of the operation unit 10 by the operator. The cloth feed amount that is the amount of movement of the feed dog 34 in the front-rear direction is determined by setting the cloth feed start position and the end position. Further, the sewing machine 1 can also set the rotation angle of the main motor 13 at the start of cloth feeding and the rotation angle of the main motor 13 at the end of cloth feeding. When the power of the sewing machine 1 is turned on, the CPU 44 starts the cloth feed amount setting process.

  The CPU 44 determines whether or not the operator inputs the set values of the cloth feed start position “STPos” and the end position “ENPos” from the operation unit 10 (S1). If not input (S1: NO), the CPU 44 proceeds to the determination of S6. When the operator operates the operation unit 10 and inputs set values of the cloth feed start position “STPos” and the end position “ENPos” (S1: YES), the CPU 44 stores the input values in the EEPROM 47 and starts the position “STPos”. "And the end position" ENPos "are set (S2). The CPU 44 sets a cloth feed amount “Pitch” which is a distance from the start position “STPos” to the end position “ENPos” (S3). In the present embodiment, the start position, the end position, and the cloth feed amount are represented by the angle of the cloth feed motor 23 output shaft, but may be represented by other values such as the number of pulses of the cloth feed motor 23. The CPU 44 sets a start angle “FeedStart” that is a rotation angle of the output shaft of the main motor 13 at the time of starting the cloth feed uniquely determined from the cloth feed start position (S4). Similarly, the CPU 44 sets a termination angle “FeedEnd” that is a rotation angle of the output shaft of the main motor 13 that is uniquely determined from the termination position of the cloth feed (S5). The end angle is a rotation angle at which the output shaft of the main motor 13 should be positioned when the cloth feed mechanism 32 reaches the cloth feed end position “ENPos”. If the operator has not input an instruction to end the process (S6: NO), the CPU 44 returns the process to the determination of S1. When the operator inputs an end instruction (S6: YES), the CPU 44 ends the cloth feed amount setting process.

  The first speed control process will be described with reference to FIG. In the first speed control process, the sewing machine 1 calculates the deviation between the target rotation angle of the output shaft of the cloth feed motor 23 and the actual rotation angle. The sewing machine 1 calculates the rotation speed of the cloth feed motor 23 based on the calculated deviation. Therefore, in the sewing machine 1, the rotation speed of the cloth feed motor 23 can follow the change in the rotation speed of the main motor 13. When the power of the sewing machine 1 is turned on, the CPU 44 starts the first speed control process.

  The CPU 44 acquires the main rotation angle “DDPOS”, which is the rotation angle of the output shaft of the main motor 13, from the main encoder 55 (S11). The CPU 44 determines whether or not the main rotation angle “DDPOS” acquired in S11 is between the start angle “FeedStart” and the end angle “FeedEnd” (S12). If the main rotation angle “DDPOS” is not between the start angle “FeedStart” and the end angle “FeedEnd” (S12: NO), the CPU 44 returns the process to S11. When the main rotation angle “DDPOS” is between the start angle “FeedStart” and the end angle “FeedEnd” (S12: YES), the CPU 44 determines the cloth feed rotation angle “RELPOS” which is the rotation angle of the output shaft of the cloth feed motor 23. "Is acquired from the cloth feed encoder 56 (S13).

  The CPU 44 sets a target rotation angle “POS1” that is the cloth feed rotation angle at which the output shaft of the cloth feed motor 23 corresponding to the main rotation angle “DDPOS” of the main motor 13 acquired in S11 is to be positioned (S14). As described above, in the sewing machine 1, the main motor 13 and the cloth feed motor 23 are synchronized. Therefore, the target rotation angle of the cloth feed motor 23 is uniquely determined from the main rotation angle “DDPOS”.

A method for setting the target rotation angle “POS1” will be described in detail. The CPU 44 calculates a feed angle “FeedDeg”, which is an angle at which the output shaft of the main motor 13 rotates while the feed dog 34 moves in the front-rear direction and feeds the cloth once, using the following formula.
FeedDeg = FeedEnd−FeedStart
Of the feed angle “FeedDeg”, the ratio of the angle that has already been rotated is:
(DDPOS-FeedStart) / FeedDeg
It becomes. Therefore, the CPU 44 can calculate the target rotation angle “POS1” by the following equation.
POS1 = STPos + Pitch (DDPOS-FeedStart) / FeedDeg

  The CPU 44 calculates a deviation between the set target rotation angle “POS1” and the cloth feed rotation angle “RELPOS” acquired from the cloth feed encoder 56 (S15). Based on the calculated deviation, the CPU 44 calculates the rotational speed “SP1” instructed to the cloth feed motor 23 (S16). Specifically, the CPU 44 calculates the rotational speed “SP1” by multiplying the deviation by a preset fixed value coefficient N. The CPU 44 outputs a cloth feed driving signal for driving the cloth feed motor 23 at the rotational speed “SP1” to the drive circuit 53 to drive the cloth feed motor 23 (S17). CPU44 returns a process to S11 and repeats the process of S11-S17. The first speed control process ends when the power of the sewing machine 1 is turned off.

  The operation confirmation process will be described with reference to FIG. In the operation confirmation processing, the sewing machine 1 confirms whether or not the main motor 13 and the cloth feed motor 23 are synchronized, and performs error processing if they are not synchronized. When the power of the sewing machine 1 is turned on, the CPU 44 starts an operation confirmation process.

  The CPU 44 acquires the main rotation angle “DDPOS”, which is the rotation angle of the output shaft of the main motor 13, from the main encoder 55 (S21). The CPU 44 determines whether or not the main rotation angle “DDPOS” acquired in S21 is between the start angle “FeedStart” and the end angle “FeedEnd” (S22). When the main rotation angle “DDPOS” is not between the start angle “FeedStart” and the end angle “FeedEnd” (S22: NO), the CPU 44 returns the process to S21. When the main rotation angle “DDPOS” is between the start angle “FeedStart” and the end angle “FeedEnd” (S22: YES), the CPU 44 determines the setting details of the operation confirmation timing previously performed by the operator (S23, S24).

  In the sewing machine 1 of the present embodiment, the operator can set the operation confirmation timing by operating the operation unit 10. The operation confirmation timing includes a constant confirmation and a predetermined position confirmation. In the constant confirmation, the operation is confirmed at predetermined intervals (for example, the interval at which the CPU 44 performs the processing of S21 to S28 or the predetermined time corresponding to the number of clocks of the CPU 44). In the constant check, the sewing machine 1 can check the operation more accurately. The predetermined position confirmation is performed when the feed dog 34 of the cloth feed mechanism 32 reaches a predetermined operation confirmation position. In the predetermined position confirmation, the sewing machine 1 can efficiently confirm the operation at a necessary timing, and the processing load on the CPU 44 is reduced.

  When the operator confirms the predetermined position, the operator can set an operation confirmation position of either a default position or an arbitrary position. When the predetermined confirmation position is set to the default position, the operation confirmation position is a position where the feed dog 34 of the cloth feed mechanism 32 is raised and lowered from the plate surface of the needle plate 15. The cloth feed mechanism 32 feeds the cloth 29 in a state where the feed dog 34 is above the needle plate 15. Therefore, the synchronization of the two motors 13 and 23 is particularly important at the position where the feed dog 34 moves up and down from the needle plate 15. By setting the predetermined confirmation position to the default position, the sewing machine 1 can efficiently confirm the operation at a particularly important timing.

  When the predetermined confirmation position is set to an arbitrary position, the operator operates the operation unit 10 to arbitrarily set the operation confirmation position. The position that can be arbitrarily set by the operator is a position between the cloth feed start position “STPos” and the end position “ENPos”. For example, when the cloth 29 is thick, the sewing needle 8 pierces the cloth 29 at an earlier timing than when the cloth 29 is thin. If the predetermined confirmation position is set to the default position when the cloth 29 is thick, the sewing needle 8 may pierce the cloth 29 before reaching the position where the feed dog 34 of the cloth feed mechanism 32 descends from the plate surface of the needle plate 15. . Therefore, when the two motors 13 and 23 are out of synchronization and the feed dog 34 descends slowly, the cloth 29 moves with the sewing needle 8 stuck. When the cloth 29 moves while being stuck in the cloth 29, the sewing needle 8 bends. The bent sewing needle 8 does not pass through the needle hole 18 and may contact the upper surface of the needle plate 15 and be damaged. By arbitrarily setting the operation confirmation position to a position that is earlier than the position where the feed dog 34 descends from the needle plate 15, the sewing machine 1 can perform operation confirmation by changing the timing according to the cloth thickness. By setting the predetermined confirmation position to an arbitrary position, the operator can confirm the operation of the sewing machine 1 at a desired confirmation position.

  If the operation confirmation timing setting is not always confirmed (S23: NO), the CPU 44 determines from the main rotation angle “DDPOS” of the main motor 13 whether or not the position of the cloth feed mechanism 32 is a predetermined operation confirmation position. (S24). As described above, the sewing machine 1 drives the cloth feed motor 23 so that the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 is synchronized with the main rotation angle “DDPOS” of the main motor 13 (see FIG. 6). The position of the cloth feed mechanism 32 is determined from the cloth feed rotation angle “RELPOS”. Therefore, the sewing machine 1 can determine the position where the cloth feed mechanism 32 should be present from the main rotation angle “DDPOS” of the main motor 13. If the position of the cloth feed mechanism 32 is not at the predetermined operation confirmation position (S24: NO), the CPU 44 returns the process to S21.

  When the operation confirmation timing setting is always confirmation (S23: YES), or when the position of the cloth feed mechanism 32 is at the predetermined operation confirmation position (S24: YES), the CPU 44 sets the cloth feed rotation angle “RELPOS”. Obtained from the feed encoder 56 (S25). The CPU 44 sets a target rotation angle “POS1” at which the output shaft of the cloth feed motor 23 corresponding to the main rotation angle “DDPOS” acquired in S21 is to be positioned (S26). The setting method of “POS1” is the same as S14 described above (see FIG. 6). The CPU 44 calculates a deviation between the set target rotation angle “POS1” and the cloth feed rotation angle “RELPOS” acquired in S25 (S27).

  The CPU 44 determines whether or not the calculated deviation is equal to or less than a threshold value (S28). The threshold can be set arbitrarily. The threshold value may be a value that can be changed by the operator operating the operation unit 10. If the deviation is less than or equal to the threshold (S28: YES), the CPU 44 determines that the main motor 13 and the cloth feed motor 23 are synchronized, and returns the process to S21. If the deviation is larger than the threshold value (S28: NO), the CPU 44 displays on the liquid crystal panel 11 an error screen indicating that the two motors 13 and 23 are out of synchronization (S29). Therefore, the operator can easily grasp that the two motors 13 and 23 are out of synchronization and take appropriate measures. In S29, the CPU 44 may notify the error by outputting an error sound from the speaker. The CPU 44 stops driving the main motor 13 and the cloth feed motor 23 (S30) and ends the operation confirmation process. Therefore, the sewing machine 1 can prevent sewing with the two motors 13 and 23 out of synchronization.

  As described above, the sewing machine 1 according to the first embodiment sets the target rotation angle “POS1” where the output shaft of the cloth feed motor 23 should be positioned from the main rotation angle “DDPOS” of the main motor 13. The sewing machine 1 calculates a deviation between the set target rotation angle “POS1” and the actual cloth feed rotation angle “RELPOS” of the cloth feed motor 23. The sewing machine 1 calculates the rotation speed of the cloth feed motor 23 based on the calculated deviation. Even when the rotation speeds of the main motor 13 and the main shaft 14 are changed, the cloth feed motor 23 is driven in synchronization with the main motor 13. Therefore, the sewing machine 1 can maintain the synchronization of the driving of the main shaft 14 and the driving of the cloth feeding mechanism 32 even if the sewing speed changes.

  The sewing machine 1 of the first embodiment can calculate the rotation speed of the cloth feed motor 23 without using the rotation speed of the main motor 13. Therefore, the sewing machine 1 of the first embodiment can appropriately keep the cloth feed motor 23 and the main motor 13 synchronized even when the main motor 13 is stopped or when the operator manually rotates the main shaft 14. In the sewing machine 1, the operator can freely set the cloth feed start position, end position, cloth feed amount, start angle, and end angle. The sewing machine 1 can drive the cloth feed motor 23 at an appropriate speed according to the set value.

  In the first embodiment, the main encoder 55 corresponds to a main rotation angle detection unit of the present invention. The cloth feed encoder 56 corresponds to a cloth feed rotation angle detector. CPU44 which acquires a main rotation angle by S11 of FIG. 6 functions as a main rotation angle acquisition part. The CPU 44 that acquires the cloth feed rotation angle in S13 of FIG. 6 functions as a cloth feed rotation angle acquisition unit. CPU44 which sets a target rotation angle by S14 of FIG. 6 functions as a cloth feed target angle setting part. The CPU 44 that calculates the deviation in S15 of FIG. 6 functions as a deviation calculation unit. The CPU 44 that calculates the rotation speed of the cloth feed motor 23 in S16 of FIG. 6 functions as a first rotation speed calculation unit. The CPU 44 that executes the cloth feed setting process of FIG. 5 functions as a setting unit.

  The process of acquiring the main rotation angle in S11 of FIG. 6 corresponds to a main rotation angle acquisition step. The process of acquiring the cloth feed rotation angle in S13 of FIG. 6 corresponds to the cloth feed rotation angle acquisition step. The process of setting the target rotation angle in S14 of FIG. 6 corresponds to the cloth feed target angle setting step. The process of calculating the deviation in S15 of FIG. 6 corresponds to a deviation calculating step. The process of calculating the rotation speed of the cloth feed motor 23 in S16 of FIG. 6 corresponds to a first rotation speed calculation step.

  A second embodiment of the present invention will be described with reference to FIG. The sewing machine 1 of the second embodiment sets the target rotation angle of the output shaft of the main motor 13 from the rotation angle of the output shaft of the cloth feed motor 23. The sewing machine 1 calculates the deviation between the set target rotation angle of the output shaft of the main motor 13 and the actual rotation angle, and calculates the rotation speed of the cloth feed motor 23. The sewing machine 1 according to the first embodiment described above sets the target rotation angle of the output shaft of the cloth feed motor 23 and calculates the rotation speed. The sewing machine 1 of the second embodiment is different from the sewing machine 1 of the first embodiment only in that the target rotation angle of the output shaft of the main motor 13 is used. The mechanical configuration, the electrical configuration, and the cloth feed amount setting process ( The operation confirmation process (see FIG. 7) and the like are the same as those in the first embodiment. Therefore, in description of 2nd embodiment, the same number is attached | subjected to the structure and process same as the sewing machine 1 of 1st embodiment, and description is abbreviate | omitted or simplified.

  When the power of the sewing machine 1 is turned on, the CPU 44 starts the second speed control process. The CPU 44 acquires the main rotation angle “DDPOS” of the main motor 13 (S11). The CPU 44 determines whether or not the main rotation angle “DDPOS” acquired in S11 is between the start angle “FeedStart” and the end angle “FeedEnd” (S12). If the main rotation angle “DDPOS” is not between the start angle “FeedStart” and the end angle “FeedEnd” (S12: NO), the CPU 44 returns the process to S11. When the main rotation angle “DDPOS” is between the start angle “FeedStart” and the end angle “FeedEnd” (S12: YES), the CPU 44 acquires the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 (S13).

The CPU 44 sets a target rotation angle “POS2” that is the main rotation angle at which the output shaft of the main motor 13 corresponding to the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 acquired in S13 is to be located (S114). A method for setting the target rotation angle “POS2” will be described in detail. The angle at which the output shaft of the cloth feed motor 23 rotates while the feed dog 34 moves in the front-rear direction and feeds the cloth once is the cloth feed amount “Pitch”. Of the cloth feed amount “Pitch”, the ratio of the angle at which the rotation has already ended is (RELPOS−STPos) / Pitch. The cloth feed start position “STPos” is set in the cloth feed amount setting process (see FIG. 5). The CPU 44 can calculate the target rotation angle “POS2” by the following equation.
POS2 = FeedStart + FeedDeg (RELPOS-STPos) / Pitch

  The CPU 44 calculates a deviation between the set target rotation angle “POS2” and the main rotation angle “DDPOS” acquired from the main encoder 55 (S115). The CPU 44 calculates a conversion value for calculating the rotation speed instructed to the cloth feed motor 23 based on the deviation calculated in S115 (S116). Specifically, the CPU 44 multiplies the deviation by (FeedDeg / Pitch) to set the deviation to a value corresponding to the deviation between the target rotation angle at which the output shaft of the cloth feed motor 23 should be positioned and the cloth feed rotation angle “RELPOS”. Convert. The CPU 44 calculates the rotational speed “SP1” instructed to the cloth feed motor 23 based on the conversion value calculated in S116 (S16). Specifically, the CPU 44 calculates the rotational speed “SP1” by multiplying the deviation by the coefficient N. The CPU 44 drives the cloth feed motor 23 at the calculated rotation speed “SP1” (S17). The CPU 44 returns the process to S11. The second speed control process ends when the power of the sewing machine 1 is turned off.

  As described above, the sewing machine 1 according to the second embodiment sets the target rotation angle “POS2” at which the output shaft of the main motor 13 should be positioned from the cloth feed rotation angle “RELPOS” of the cloth feed motor 23. The sewing machine 1 calculates a deviation between the set target rotation angle “POS2” and the actual main rotation angle “DDPOS” of the main motor 13. The sewing machine 1 calculates the rotation speed of the cloth feed motor 23 based on the calculated deviation. Even when the rotation speeds of the main motor 13 and the main shaft 14 change, the cloth feed motor 23 rotates in synchronization with the main motor 13. Therefore, the sewing machine 1 can maintain the synchronization of the driving of the main shaft 14 and the driving of the cloth feeding mechanism 32 even if the sewing speed changes. In particular, the sewing machine 1 of the second embodiment can appropriately keep the cloth feed motor 23 and the main motor 13 synchronized even when the main motor 13 is stopped or when the operator manually rotates the main shaft 14.

  In the second embodiment, the CPU 44 that sets the target rotation angle in S114 of FIG. 8 functions as the main target angle setting unit of the present invention. The CPU 44 that calculates the deviation in S115 of FIG. 8 functions as a main deviation calculation unit. The CPU 44 that calculates the rotation speed in S116 and S16 of FIG. 8 functions as a “first rotation speed calculation unit”. The process of setting the target rotation angle in S114 of FIG. 8 corresponds to a main target angle setting step. The process of calculating the deviation in S115 in FIG. 8 corresponds to a main deviation calculating step. The process of calculating the rotation speed in S116 and S16 of FIG. 8 corresponds to a “first rotation speed calculation step”.

  A third embodiment of the present invention will be described with reference to FIG. The sewing machine 1 of the third embodiment calculates the time required for the output shaft of the main motor 13 to reach the terminal angle “FeedEnd”. The end angle “FeedEnd” is a main rotation angle at which the output shaft of the main motor 13 should be positioned when the cloth feed mechanism 32 reaches the cloth feed end position. The sewing machine 1 calculates the remaining rotation angle of the cloth feed motor 23 until the cloth feed mechanism 32 reaches the end position. The sewing machine 1 calculates the rotation speed for the cloth feed motor 23 to rotate the remaining rotation angle in the calculated required time. The sewing machine 1 of the third embodiment is different from the first and second embodiments only in that the third speed control process is executed instead of the first speed control process and the second speed control process. Therefore, in description of 3rd embodiment, the same number is attached | subjected to the structure and process same as the sewing machine 1 of 1st, 2nd embodiment, and description is abbreviate | omitted or simplified.

  When the power of the sewing machine 1 is turned on, the CPU 44 starts the third speed control process. The CPU 44 acquires the main rotation angle “DDPOS” of the main motor 13 from the main encoder 55 (S41). The CPU 44 determines whether or not the main rotation angle “DDPOS” acquired in S41 is between the start angle “FeedStart” and the end angle “FeedEnd” (S42). When the main rotation angle “DDPOS” is not between the start angle “FeedStart” and the end angle “FeedEnd” (S42: NO), the CPU 44 returns the process to S41. When the main rotation angle “DDPOS” is between the start angle “FeedStart” and the end angle “FeedEnd” (S42: YES), the CPU 44 determines the end angle that is the main rotation angle when the cloth feed mechanism 32 reaches the end position. “FeedEnd” is acquired from the EEPROM 47 (S43). The CPU 44 subtracts the current main rotation angle “DDPOS” from the end angle “FeedEnd” to calculate the remaining rotation angle “RemM” until the output shaft of the main motor 13 reaches the end angle (S44).

The CPU 44 obtains the rotational speed “DDSspeed (unit: rpm)” of the main motor 13 (S45). The rotation speed is a rotation speed detection process (not shown) executed in parallel with the third speed control process, and the change amount (unit: rotation speed) of the main rotation angle acquired from the main encoder 55 is sampled (unit: minute). ). The CPU 44 calculates a required time T (unit: minutes) until the output shaft of the main motor 13 reaches the terminal angle “FeedEnd” by the following formula (S46).
T = RemM / (360 · DDSspeed)

The CPU 44 acquires the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 from the cloth feed encoder 56 (S47). The CPU 44 subtracts the current cloth feed rotation angle “RELPOS” from the cloth feed end position “ENPos” to calculate the remaining rotation angle “RemF” until the output shaft of the cloth feed motor 23 reaches the end position. (S48). The CPU 44 calculates the rotational speed “SP2” necessary for the cloth feed motor 23 to rotate the remaining rotational angle “RemF” for the required time T by the following formula (S49).
SP2 = RemF / (360 · T)
The CPU 44 drives the cloth feed motor 23 at the calculated rotation speed “SP2” (S50). The CPU 44 returns the process to S41. The third speed control process ends when the power of the sewing machine 1 is turned off.

  As described above, the sewing machine 1 of the third embodiment calculates the required time T until the output shaft of the main motor 13 reaches the terminal angle. The sewing machine 1 calculates the remaining rotation angle “RemF” of the cloth feed motor 23 until the cloth feed mechanism 32 reaches the end position. The sewing machine 1 calculates the rotation speed “SP2” for the cloth feed motor 23 to rotate the remaining rotation angle “RemF” in the required time T. The cloth feed motor 23 is synchronized with the main motor 13 by driving the cloth feed motor 23 at the rotation speed “SP2”. The time when the cloth feed mechanism 32 reaches the end position coincides with the time when the output shaft of the main motor 13 reaches the end angle. Therefore, the sewing machine 1 can maintain the synchronization of the driving of the main shaft 14 and the driving of the cloth feeding mechanism 32 even if the sewing speed changes. The sewing machine 1 of the third embodiment does not use the deviation between the positions of the output shafts of the two motors 13 and 23 and the target position. The sewing machine 1 of the third embodiment can appropriately control the two motors 13 and 23 without using a deviation when the rotational speed of the main motor 13 is increasing.

  In the third embodiment, the CPU 44 that acquires the main rotation angle in S41 of FIG. 9 functions as the main rotation angle acquisition unit of the present invention. The CPU 44 that acquires the terminal angle in S43 of FIG. 9 functions as a terminal angle acquisition unit. The CPU 44 that calculates the remaining rotation angle of the main motor 13 in S44 of FIG. 9 functions as a main rotation angle remaining amount calculation unit. The CPU 44 that acquires the rotation speed (main rotation speed) of the main motor 13 in S45 of FIG. 9 functions as a speed acquisition unit. The CPU 44 that calculates the required time T in S46 of FIG. 9 functions as a time calculation unit. The CPU 44 that acquires the cloth feed rotation angle in S47 of FIG. 9 functions as a cloth feed rotation angle acquisition unit. The CPU 44 that calculates the remaining rotation angle of the cloth feed motor 23 in S48 of FIG. 9 functions as a cloth feed rotation angle remaining amount calculation unit. The CPU 44 that calculates the rotation speed instructed to the cloth feed motor 23 in S49 of FIG. 9 functions as a second rotation speed calculation unit.

  The process of acquiring the main rotation angle in S41 of FIG. 9 corresponds to a main rotation angle acquisition step. The process of acquiring the terminal angle in S43 of FIG. 9 corresponds to the terminal angle acquisition step. The process of calculating the remaining rotation angle of the main motor 13 in S44 of FIG. 9 corresponds to a main rotation angle remaining amount calculating step. The process of acquiring the rotation speed of the main motor 13 in S45 of FIG. 9 corresponds to a speed acquisition step. The process of calculating the required time T in S46 of FIG. 9 corresponds to a time calculation step. The process of acquiring the cloth feed rotation angle in S47 of FIG. 9 corresponds to the cloth feed rotation angle acquisition step. The process of calculating the remaining rotation angle of the cloth feed motor 23 in S48 of FIG. 9 corresponds to the cloth feed rotation angle remaining amount calculating step. The process of calculating the rotation speed instructed to the cloth feed motor 23 in S49 of FIG. 9 corresponds to a second rotation speed calculation step.

  A fourth embodiment of the present invention will be described with reference to FIG. The sewing machine 1 of the fourth embodiment calculates the rotational speed “SP1” according to the deviation between the target rotational angle and the actual rotational angle. The sewing machine 1 calculates the rotational speed “SP2” based on the rotational speed of the main motor 13. The sewing machine 1 changes the control method of the cloth feed motor 23 according to the rotation speed of the main motor 13. The sewing machine 1 of the fourth embodiment is different from the first to third embodiments only in that the fourth speed control process is executed instead of the first to third speed control processes. Therefore, in description of 4th embodiment, the same number is attached | subjected to the structure and process same as the sewing machine 1 of 1st-4th embodiment, and description is abbreviate | omitted or simplified.

  When the power of the sewing machine 1 is turned on, the CPU 44 starts the fourth speed control process. The CPU 44 acquires the main rotation angle “DDPOS” of the main motor 13 from the main encoder 55 (S61). The CPU 44 determines whether or not the main rotation angle “DDPOS” acquired in S61 is between the start angle “FeedStart” and the end angle “FeedEnd” (S62). When the main rotation angle “DDPOS” is not between the start angle “FeedStart” and the end angle “FeedEnd” (S62: NO), the CPU 44 returns the process to S61. When the main rotation angle “DDPOS” is between the start angle “FeedStart” and the end angle “FeedEnd” (S62: YES), the CPU 44 obtains the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 from the cloth feed encoder 56. (S63). The CPU 44 sets a target rotation angle “POS1” where the output shaft of the cloth feed motor 23 corresponding to “DDPOS” acquired in S61 should be positioned (S64). The method of setting the target rotation angle “POS1” is the same as S14 (see FIG. 6) described above. The CPU 44 calculates a deviation between the set target rotation angle “POS1” and the cloth feed rotation angle “RELPOS” acquired in S63 (S65). The CPU 44 calculates the rotational speed “SP1” instructed to the cloth feed motor 23 by multiplying the calculated deviation by the coefficient N (S66).

  The CPU 44 acquires the rotational speed “DDSspeed” of the main motor 13 (S67). The CPU 44 determines whether or not the rotational speed “DDSspeed” is equal to or less than a threshold value of 300 (rpm) (S68). The threshold value is not limited to 300. The threshold value may be changed by the operator operating the operation unit 10. If the rotational speed “DDSspeed” is 300 or less (S68: YES), the CPU 44 drives the cloth feed motor 23 at the rotational speed “SP1” (S69). The CPU 44 returns the process to S61.

  If the rotation speed “DDSspeed” is greater than 300 (S68: NO), the CPU 44 acquires the terminal angle “FeedEnd” from the EEPROM 47 (S71). The CPU 44 subtracts the current main rotation angle “DDPOS” from the end angle “FeedEnd” to calculate the remaining rotation angle “RemM” until the output shaft of the main motor 13 reaches the end angle (S72). The CPU 44 calculates a required time T until the output shaft of the main motor 13 reaches the terminal angle “FeedEnd” (S73). The calculation method of S73 is the same as S46 (see FIG. 9) described above. The CPU 44 subtracts the current cloth feed rotation angle “RELPOS” from the cloth feed end position “ENPos” to calculate the remaining rotation angle “RemF” until the output shaft of the cloth feed motor 23 reaches the end position. (S74). The CPU 44 calculates the rotation speed “SP2” by dividing the remaining rotation angle “RemF” by the required time T (S75).

The CPU 44 determines whether or not the rotational speed “DDSspeed” is smaller than a threshold value of 3000 (rpm) (S76). The threshold value is not limited to 3000, but needs to be larger than the threshold value used in the determination of S68. If the rotational speed “DDSspeed” is larger than 300 and smaller than 3000 (S76: YES), the CPU 44 calculates the rotational speed “SP3” of the cloth feed motor 23 at a specific ratio from the rotational speeds “SP1” and “SP2”. (S77, S78). Specifically, the CPU 44 calculates the ratio “rt” of SP1 occupying SP3 by the following formula (S77).
rt = (3000−DDSspeed) / 2700
The CPU 44 calculates the rotational speed “SP3” instructed to the cloth feed motor 23 by the following formula (S78).
SP3 = rt.SP1 + (1-rt) .SP2
As for the rotational speed “SP3”, as the rotational speed “DDSspeed” approaches 3000, the proportion of SP1 in SP3 decreases and the proportion of SP2 increases. The CPU 44 drives the cloth feed motor 23 at the calculated rotation speed “SP3” (S79), and returns the process to S61.

  If the rotational speed “DDSspeed” is 3000 or more (S76: NO), the CPU 44 drives the cloth feed motor 23 at the rotational speed “SP2” (S81), and returns the process to S61.

  As described above, the sewing machine 1 according to the fourth embodiment calculates the rotation speed “SP1” according to the deviation between the target rotation angle and the actual rotation angle. The sewing machine 1 calculates the rotational speed “SP2” based on the rotational speed of the main motor 13. According to the rotational speed “SP1”, the sewing machine 1 can appropriately keep the cloth feed motor 23 and the main motor 13 synchronized even when the main motor 13 is stopped or when the operator manually rotates the main shaft 14. Considering the rotational speed “SP2”, the sewing machine 1 keeps the two motors 13 and 23 synchronized by instructing the cloth feeding motor 23 to an appropriate rotational speed even when the rotational speed of the main shaft 14 is increased. Can do. The sewing machine 1 can drive the cloth feed mechanism more appropriately by changing the control method of the cloth feed motor 23 in accordance with the rotational speed “DDSspeed” of the main motor 13. More specifically, the sewing machine 1 changes the ratio of the rotational speed “SP1” suitable for the low speed and the rotational speed “SP2” suitable for the high speed in accordance with the rotational speed “DDSspeed”, thereby changing the rotational speed “SP3” of the cloth feed motor 23. Can be calculated. When the rotational speed “DDSspeed” is an intermediate speed (300 to 3000 in this embodiment), the sewing machine 1 appropriately calculates the rotational speed “SP1” and the rotational speed “SP2” and calculates the rotational speed “SP3”. it can. Therefore, the sewing machine 1 can drive the cloth feed motor 23 at a rotation speed more suitable for the rotation speed “DDSspeed”.

  In the fourth embodiment, the CPU 44 that acquires the main rotation angle in S61 of FIG. 10 functions as the main rotation angle acquisition unit of the present invention. The CPU 44 that acquires the cloth feed rotation angle in S63 of FIG. 10 functions as a cloth feed rotation angle acquisition unit. The CPU 44 that sets the target rotation angle in S64 of FIG. 10 functions as a cloth feed target angle setting unit. The CPU 44 that calculates the deviation in S65 of FIG. 10 functions as a cloth feed deviation calculation unit. The CPU 44 that calculates the rotation speed of the cloth feed motor 23 in S66 of FIG. 10 functions as a first rotation speed calculation unit. The CPU 44 that acquires the terminal angle in S71 of FIG. 10 functions as a terminal angle acquisition unit. The CPU 44 that calculates the remaining rotation angle of the main motor 13 in S72 of FIG. 10 functions as a main rotation angle remaining amount calculation unit. The CPU 44 that acquires the rotation speed (main rotation speed) of the main motor 13 in S67 of FIG. 10 functions as a speed acquisition unit. The CPU 44 that calculates the required time T in S73 of FIG. 10 functions as a time calculation unit. The CPU 44 that calculates the remaining rotation angle of the cloth feed motor 23 in S74 of FIG. 10 functions as a cloth feed rotation angle remaining amount calculation unit. The CPU 44 that calculates the rotation speed instructed to the cloth feed motor 23 in S75 of FIG. 10 functions as a second rotation speed calculation unit. The CPU 44 that determines whether or not the main rotation speed is equal to or less than the threshold value in S68 of FIG. 10 functions as a determination unit. The CPU 44 that drives the cloth feed motor 23 in S69 of FIG. 10 functions as a low-speed drive unit. The CPU 44 that drives the cloth feed motor 23 in S79 and S81 of FIG. 10 functions as a high-speed drive unit. The CPU 44 that calculates the rotation speed in S76 to S78 of FIG. 10 functions as a third rotation speed calculation unit.

  A fifth embodiment of the present invention will be described with reference to FIG. The sewing machine 1 of the fifth embodiment sets the target rotation angle of the output shaft of the main motor 13 from the rotation angle of the output shaft of the cloth feed motor 23. The sewing machine 1 calculates the deviation between the set target rotation angle of the output shaft of the main motor 13 and the actual rotation angle, and calculates the rotation speed of the main motor 13. The sewing machine 1 of the fifth embodiment is different from the sewing machine 1 of the second embodiment only in that the rotational speed of the main motor 13 is calculated. Therefore, in description of 5th embodiment, the same number is attached | subjected to the structure and process same as the sewing machine 1 of 2nd embodiment, and description is abbreviate | omitted or simplified.

  When the power of the sewing machine 1 is turned on, the CPU 44 starts the fifth speed control process. The CPU 44 acquires the main rotation angle “DDPOS” of the main motor 13 (S11). The CPU 44 determines whether or not the main rotation angle “DDPOS” acquired in S11 is between the start angle “FeedStart” and the end angle “FeedEnd” (S12). If the main rotation angle “DDPOS” is not between the start angle “FeedStart” and the end angle “FeedEnd” (S12: NO), the CPU 44 returns the process to S11. When the main rotation angle “DDPOS” is between the start angle “FeedStart” and the end angle “FeedEnd” (S12: YES), the CPU 44 acquires the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 (S13). .

  The CPU 44 sets a target rotation angle “POS2” that is the main rotation angle at which the output shaft of the main motor 13 corresponding to the cloth feed rotation angle “RELPOS” of the cloth feed motor 23 acquired in S13 is to be located (S114).

  The CPU 44 calculates a deviation between the set target rotation angle “POS2” and the main rotation angle “DDPOS” acquired from the main encoder 55 (S115). Based on the calculated deviation, the CPU 44 calculates the rotational speed “DDSP” instructed to the main motor 13 (S216). Specifically, the CPU 44 calculates the rotation speed “DDSP” by multiplying the deviation by a fixed value coefficient M set in advance. The CPU 44 drives the main motor 13 at the calculated rotation speed “DDSP” (S217). The CPU 44 returns the process to S11.

  As described above, the sewing machine 1 of the fifth embodiment calculates the rotational speed of the main motor 13 based on the calculated deviation. The main motor 13 rotates in synchronization with the cloth feed motor 23. Therefore, the sewing machine 1 can follow the rotational speed of the main shaft 14 to the cloth feeding speed. In the fifth embodiment, the CPU 44 that calculates the rotation speed of the main motor 13 in S216 of FIG. 11 functions as a main rotation speed calculation unit of the present invention.

  The above embodiment can be variously modified. The sewing machine 1 of the above embodiment moves the cloth feed mechanism 32 up and down by the main motor 13. Therefore, the vertical movement of the cloth feed mechanism 32 and the vertical movement of the sewing needle 8 are mechanically synchronized. However, the present invention can also be applied to a sewing machine provided with a motor that moves the cloth feed mechanism 32 up and down (specifically, a motor that rotates the drive shaft 41 in FIG. 3) separately from the main motor 13. The sewing machine can drive at least one of a motor that moves the cloth feed mechanism 32 up and down and a cloth feed motor 23 that moves in the horizontal direction by the driving method of the present invention.

  The specific calculation method of the rotation speeds SP1, SP2, and SP3 may be changed. For example, the sewing machine 1 of the fourth embodiment calculates SP3 so that the ratio of SP2 increases in proportion to the value of the rotational speed “DDSspeed” (see S77 and S78 in FIG. 10). The value of the rotational speed “DDSspeed” and the ratio of SP2 may not be proportional. The sewing machine 1 stores a table associating the value of the rotational speed “DDSspeed” with the ratios of SP1 and SP2 in the ROM 45 or the like, acquires the ratio corresponding to the value of the rotational speed “DDSspeed” from the table, and calculates SP3. Also good. The method of calculating SP1 from the deviation in S16 of FIG. 6, S16 of FIG. 8, and S66 of FIG. 10 can be changed. The sewing machine 1 may calculate SP1 using a table associating the deviation with the value of SP1. The method of calculating the rotational speed “DDSP” of the main motor 13 in S216 of FIG. 11 can be similarly changed.

  The sewing machine 1 of the above embodiment uses the deviation between the target rotation angle “POS1” of the cloth feed motor 23 and the actual cloth feed rotation angle “RELPOS” in the operation check process shown in FIG. Determine synchronization. The sewing machine 1 may determine synchronization using a deviation between the target rotation angle “POS2” of the main motor 13 and the actual main rotation angle “DDPOS”. Similarly, the sewing machine 1 may calculate SP1 using the deviation between the target rotation angle “POS2” and the main rotation angle “DDPOS” in S64 to S66 of the fourth speed control process of FIG. In other words, the processes of S114 to S116 and S16 of FIG. 8 may be performed instead of S64 to S66 of FIG.

  In the sewing machine 1 of the above embodiment, in the third speed control process shown in FIG. 9, the time T required until the output shaft of the main motor 13 reaches the terminal angle “FeedEnd” is determined as the remaining rotation angle “ Calculation based on “RemM”. The sewing machine 1 may use a table in which the DDSspeed and the required time T are associated with each other when the rotational speed “DDSspeed” of the main motor 13 is determined in advance.

  The processing order of the fourth speed control process shown in FIG. 10 can be changed. For example, the sewing machine 1 acquires the rotational speed “DDSspeed” of the main motor 13 immediately after the start of the fourth speed control process, and determines which of SP1, SP2, and SP3 is used to drive the cloth feed motor 23. Also good. The sewing machine 1 may calculate the rotational speed determined to be used in subsequent processing and drive the cloth feed motor 23.

DESCRIPTION OF SYMBOLS 1 Sewing machine 7 Needle bar 8 Sewing needle 10 Operation part 13 Main motor 14 Main shaft 15 Needle plate 22 Pedal 23 Cloth feed motor 32 Cloth feed mechanism 34 Feed dog 44 CPU
45 ROM
47 EEPROM
55 Main encoder 56 Cloth feed encoder

Claims (11)

In a sewing machine including a main motor that drives a spindle that moves a sewing needle up and down, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth,
A main rotation angle detector that detects a main rotation angle that is the rotation angle of the output shaft of the main motor;
A main rotation angle acquisition unit for acquiring a detection result of the main rotation angle detected by the main rotation angle detection unit;
A cloth feed rotation angle detection unit for detecting a cloth feed rotation angle which is a rotation angle of the output shaft of the cloth feed motor;
A cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
A cloth feed target angle setting unit that sets a target rotation angle at which the output shaft of the cloth feed motor should be positioned corresponding to the main rotation angle from the main rotation angle acquired by the main rotation angle acquisition unit;
A cloth feed deviation calculating section for calculating a deviation between the target rotation angle set by the cloth feed target angle setting section and the cloth feed rotation angle acquired by the cloth feed rotation angle acquiring section;
A sewing machine comprising: a first rotation speed calculation unit that calculates a rotation speed instructed to the cloth feed motor based on the deviation. In a sewing machine including a main motor that drives a spindle that moves a sewing needle up and down, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth,
A main rotation angle detector that detects a main rotation angle that is the rotation angle of the output shaft of the main motor;
A main rotation angle acquisition unit for acquiring a detection result of the main rotation angle detected by the main rotation angle detection unit;
A cloth feed rotation angle detection unit for detecting a cloth feed rotation angle which is a rotation angle of the output shaft of the cloth feed motor;
A cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
A main target angle setting unit for setting a target rotation angle at which the output shaft of the main motor should be positioned corresponding to a cloth feed rotation angle, from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit;
A main deviation calculation unit that calculates a deviation between the target rotation angle set by the main target angle setting unit and the main rotation angle acquired by the main rotation angle acquisition unit;
A sewing machine comprising: a first rotation speed calculation unit that calculates a rotation speed instructed to the cloth feed motor based on the deviation. In a sewing machine including a main motor that drives a spindle that moves a sewing needle up and down, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth,
A main rotation angle detector that detects a main rotation angle that is the rotation angle of the output shaft of the main motor;
A main rotation angle acquisition unit for acquiring a detection result of the main rotation angle detected by the main rotation angle detection unit;
A terminal angle obtaining unit that obtains a terminal angle that is a main rotation angle at which the output shaft of the main motor should be positioned when the cloth feed mechanism reaches a cloth feed terminal position;
Based on the terminal angle acquired by the terminal angle acquisition unit and the main rotation angle acquired by the main rotation angle acquisition unit, a remaining rotation angle until the output shaft of the main motor reaches the terminal angle is calculated. A main rotation angle remaining amount calculation unit;
A speed acquisition unit that acquires a main rotation speed that is a rotation speed of the main motor;
Based on the remaining rotation angle calculated by the main rotation angle remaining amount calculation unit and the main rotation speed acquired by the speed acquisition unit, the time required for the output shaft of the main motor to reach the terminal angle is calculated. A time calculation unit to calculate,
A cloth feed rotation angle detection unit for detecting a cloth feed rotation angle which is a rotation angle of the output shaft of the cloth feed motor;
A cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
Calculating the remaining rotation angle of the cloth feed motor until the cloth feed mechanism reaches the cloth feed end position from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit. And
The second rotation speed calculation for calculating the remaining rotation angle calculated by the cloth feed rotation angle remaining amount calculation unit to calculate the rotation speed necessary for the cloth feed motor to rotate for the required time calculated by the time calculation unit. A sewing machine with A terminal angle obtaining unit that obtains a terminal angle that is a main rotation angle at which the output shaft of the main motor should be positioned when the cloth feed mechanism reaches a cloth feed terminal position;
Based on the terminal angle acquired by the terminal angle acquisition unit and the main rotation angle acquired by the main rotation angle acquisition unit, a remaining rotation angle until the output shaft of the main motor reaches the terminal angle is calculated. A main rotation angle remaining amount calculating unit,
A speed acquisition unit that acquires a main rotation speed that is a rotation speed of the main motor;
Based on the remaining rotation angle calculated by the main rotation angle remaining amount calculation unit and the rotation speed acquired by the speed acquisition unit, a time required until the output shaft of the main motor reaches the terminal angle is calculated. A time calculator,
Calculating the remaining rotation angle of the cloth feed motor until the cloth feed mechanism reaches the cloth feed end position from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit. And
The second rotation speed calculation for calculating the remaining rotation angle calculated by the cloth feed rotation angle remaining amount calculation unit to calculate the rotation speed necessary for the cloth feed motor to rotate for the required time calculated by the time calculation unit. And
A determination unit that determines whether the main rotation speed acquired by the speed acquisition unit is equal to or less than a threshold;
When the determination unit determines that the main rotation speed is equal to or less than the threshold, a low-speed driving unit that drives the cloth feed motor at the rotation speed calculated by the first rotation speed calculation unit;
A high-speed driving unit that drives the cloth feed motor based on at least the rotation speed calculated by the second rotation speed calculation unit when the determination unit determines that the main rotation speed is greater than the threshold value. The sewing machine according to claim 1 or 2, comprising the sewing machine. Third rotation speed calculation for calculating a rotation speed for driving the cloth feed motor from a rotation speed calculated by the first rotation speed calculation section and a rotation speed calculated by the second rotation speed calculation section at a specific ratio. Further comprising
The third rotation speed calculation unit calculates a rotation speed for driving the cloth feed motor by changing the specific ratio according to the main rotation speed,
The high-speed driving unit drives the cloth feed motor at the rotation speed calculated by the third rotation speed calculation unit when the determination unit determines that the main rotation speed is greater than the threshold value. The sewing machine according to 1.   The sewing machine according to any one of claims 3 to 5, further comprising a setting unit capable of setting the end position and the end angle of the cloth feed in the cloth feed mechanism. In a sewing machine including a main motor that drives a spindle that moves a sewing needle up and down, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth,
A main rotation angle detector that detects a main rotation angle that is the rotation angle of the output shaft of the main motor;
A main rotation angle acquisition unit for acquiring a detection result of the main rotation angle detected by the main rotation angle detection unit;
A cloth feed rotation angle detection unit for detecting a cloth feed rotation angle which is a rotation angle of the output shaft of the cloth feed motor;
A cloth feed rotation angle acquisition unit that acquires a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
A main target angle setting unit for setting a target rotation angle at which the output shaft of the main motor should be positioned corresponding to a cloth feed rotation angle, from the cloth feed rotation angle acquired by the cloth feed rotation angle acquisition unit;
A main deviation calculation unit that calculates a deviation between the target rotation angle set by the main target angle setting unit and the main rotation angle acquired by the main rotation angle acquisition unit;
A sewing machine comprising: a main rotation speed calculation unit that calculates a rotation speed instructed to the main motor based on the deviation. A main motor that drives a main shaft that moves the sewing needle up and down, a main rotation angle detector that detects a main rotation angle that is a rotation angle of the output shaft of the main motor, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth In a sewing machine control method executed by a sewing machine including a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor,
A main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector;
A cloth feed rotation angle acquisition step of acquiring a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
A cloth feed target angle setting step for setting a target rotation angle at which the output shaft of the cloth feed motor should be positioned corresponding to the main rotation angle from the main rotation angle acquired in the main rotation angle acquisition step;
A cloth feed deviation calculating step for calculating a deviation between the target rotation angle set in the cloth feed target angle setting step and the cloth feed rotation angle acquired in the cloth feed rotation angle acquiring step;
A sewing machine control method comprising: a first rotation speed calculation step of calculating a rotation speed instructed to the cloth feed motor based on the deviation. A main motor that drives a main shaft that moves the sewing needle up and down, a main rotation angle detector that detects a main rotation angle that is a rotation angle of the output shaft of the main motor, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth In a sewing machine control method executed by a sewing machine including a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor,
A main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector;
A cloth feed rotation angle acquisition step of acquiring a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
A main target angle setting step for setting a target rotation angle at which the output shaft of the main motor should be positioned corresponding to a cloth feed rotation angle from the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step;
A main deviation calculation step for calculating a deviation between the target rotation angle set in the main target angle setting step and the main rotation angle acquired in the main rotation angle acquisition step;
A sewing machine control method comprising: a first rotation speed calculation step of calculating a rotation speed instructed to the cloth feed motor based on the deviation. A main motor that drives a main shaft that moves the sewing needle up and down, a main rotation angle detector that detects a main rotation angle that is a rotation angle of the output shaft of the main motor, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth In a sewing machine control method executed by a sewing machine including a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor,
A main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector;
A terminal angle acquisition step of acquiring a terminal angle that is a main rotation angle at which the output shaft of the main motor should be positioned when the cloth feed mechanism reaches a cloth feed terminal position;
Based on the terminal angle acquired in the terminal angle acquisition step and the main rotation angle acquired in the main rotation angle acquisition step, a remaining rotation angle until the output shaft of the main motor reaches the terminal angle is calculated. A main rotation angle remaining amount calculating step,
A speed acquisition step of acquiring a main rotation speed which is a rotation speed of the main motor;
Based on the remaining rotation angle calculated in the main rotation angle remaining amount calculation step and the main rotation speed acquired in the speed acquisition step, the time required for the output shaft of the main motor to reach the terminal angle is calculated. A time calculating step to calculate;
A cloth feed rotation angle acquisition step of acquiring a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
Calculate the remaining rotation angle of the cloth feed motor from the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step until the cloth feed mechanism reaches the cloth feed end position. Steps,
The second rotation speed calculation for calculating the rotation speed necessary for the cloth feed motor to rotate in the required time calculated in the time calculation step with respect to the remaining rotation angle calculated in the cloth feed rotation angle remaining amount calculation step. A method for controlling a sewing machine including steps and A main motor that drives a main shaft that moves the sewing needle up and down, a main rotation angle detector that detects a main rotation angle that is a rotation angle of the output shaft of the main motor, and a cloth feed motor that drives a cloth feed mechanism that feeds the cloth In a sewing machine control method executed by a sewing machine including a cloth feed rotation angle detection unit that detects a cloth feed rotation angle that is a rotation angle of an output shaft of the cloth feed motor,
A main rotation angle acquisition step of acquiring a detection result of the main rotation angle detected by the main rotation angle detector;
A cloth feed rotation angle acquisition step of acquiring a detection result of the cloth feed rotation angle detected by the cloth feed rotation angle detection unit;
A main target angle setting step for setting a target rotation angle at which the output shaft of the main motor should be positioned corresponding to a cloth feed rotation angle from the cloth feed rotation angle acquired in the cloth feed rotation angle acquisition step;
A main deviation calculation step for calculating a deviation between the target rotation angle set in the main target angle setting step and the main rotation angle acquired in the main rotation angle acquisition step;
And a main rotational speed calculating step of calculating a rotational speed instructed to the main motor based on the deviation.

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