JP2009172001A - Sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sewing machine not generating delay in the operation of a cloth moving mechanism. <P>SOLUTION: The sewing machine 1 includes a needle bar, a vertical movement mechanism, a sewing machine motor 41, the cloth moving mechanism, an X-axis motor 21 and a Y-axis motor 23 for driving the cloth moving mechanism, an X-axis encoder 22 for detecting the rotation angle of the X-axis motor, a Y-axis encoder 24 for detecting the rotation angle of the Y-axis motor, a main controller 10 for performing the feedback control of the X-axis motor 21 and the Y-axis motor 23, and a sewing machine motor speed controller 30 for controlling the sewing machine motor 41. The main controller 10 adds and subtracts the command speed V1 of the sewing machine motor 41 according to the required torque T2 of the X-axis motor 21 and the required torque T3 of the Y-axis motor 23. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  According to the present invention, in a sewing machine in which a cloth movement mechanism moves a cloth in response to vertical movement of a needle bar and performs sewing, a sewing machine motor as a drive source for the needle bar and a motor as a drive source for the cloth movement mechanism are provided separately. Related to the sewing machine.

  Conventionally, the cloth moving mechanism that holds the cloth according to the vertical movement timing of the needle bar that holds the sewing needle according to the sewing data that records the pattern of the needle drop position is moved horizontally along the needle plate with respect to the needle bar. A sewing machine that performs sewing by moving a cloth relative to each other is known. At this time, as a process to synchronize the vertical movement timing of the needle bar and the cloth movement timing by the cloth movement mechanism, the time required for the pulse motor driving the cloth movement mechanism to rotate the predetermined rotation amount is measured. A method is known in which a delay in movement of the cloth moving mechanism is detected by comparing with a predetermined required time, and the sewing machine motor is decelerated or stopped in accordance with the delay. A method of detecting a delay in movement of the cloth movement mechanism by comparing a rotation amount per predetermined time of the pulse motor with a predetermined rotation amount, and decelerating or stopping the rotation speed of the sewing machine motor according to the delay. Is known (for example, Patent Document 1).

Each of the above methods includes table data for the control device of the sewing machine to control the driving of the pulse motor. Specifically, when the time required for the pulse motor to rotate the predetermined amount of rotation is measured and compared with the predetermined required time, the predetermined amount of rotation of the pulse motor and the predetermined required time Is used to detect a delay in driving the pulse motor. In addition, when comparing the rotation amount per predetermined time of the pulse motor with the planned rotation amount, table data that associates the predetermined time with the planned rotation amount of the pulse motor is used, and the driving of the pulse motor is performed. A delay is detected.
JP-A-2005-87251

  However, in the synchronization process between the needle bar and the cloth moving mechanism according to the conventional method, the operation of the pulse motor is already delayed when the rotational speed of the sewing machine motor is decelerated or stopped. In other words, because the operation of the pulse motor is delayed from the scheduled time, processing such as deceleration and stop of the rotation speed of the sewing machine motor is performed only after the operation timing of the cloth movement mechanism is delayed with respect to the vertical movement timing of the needle bar. I will not. Therefore, immediately after the operation of the pulse motor is delayed, the operation timing of the cloth moving mechanism is delayed with respect to the vertical movement timing of the needle bar, so that sewing is performed at the needle drop position deviated from the planned needle drop position, There was a problem that the planned sewing results were not achieved.

  In view of the above-described problems, an object of the present invention is to provide a sewing machine that does not cause a delay in the operation of the cloth moving mechanism.

  The invention according to claim 1 is a needle bar that is provided so as to be movable up and down while holding a sewing needle, and a vertical movement mechanism that connects the needle bar and the main shaft of the sewing machine to convert rotational motion into vertical motion. A sewing machine motor that rotates the spindle, a cloth moving mechanism that holds the cloth and moves the cloth along a horizontal plane perpendicular to the vertical movement of the needle bar, and a cloth moving motor that drives the cloth moving mechanism. A sewing means for performing sewing by moving the cloth with respect to the vertical movement of the needle bar, and detecting a rotation angle of the cloth movement motor; a command value of the cloth movement amount; and the detection The cloth movement motor control means for calculating the output torque of the cloth movement motor from the rotation angle of the cloth movement motor detected by the means and performing feedback control of the cloth movement motor, and based on the command value of the sewing machine motor speed Sewing machine motor Sewing machine motor control means for controlling the sewing machine motor speed adjusting means for adding and subtracting a command value of the sewing machine motor speed according to the torque value of the cloth movement motor calculated by the cloth movement motor control means. It is characterized by.

  According to a second aspect of the present invention, in the sewing machine according to the first aspect, the cloth movement motor control means is configured to obtain a PI from a deviation between a command value of the cloth movement amount and a rotation angle of the cloth movement motor detected by the detection means. The torque value is calculated by performing control or PID control.

  According to a third aspect of the present invention, in the sewing machine according to the first or second aspect, the cloth movement mechanism is provided on each of the two cloth movement motors for driving in two directions and the two cloth movement motors. Two detection means and two cloth movement motor control means provided in the two cloth movement motors, respectively, and the sewing machine motor speed adjustment means is configured to provide torque values of the two cloth movement motor control means. Alternatively, the sewing machine motor is controlled by a smaller torque value or command value among two command values of the machine motor speed calculated according to the torque value.

  According to a fourth aspect of the present invention, there is provided the sewing machine according to any one of the first to third aspects, further comprising a sewing machine motor speed detecting unit that detects a rotation speed of the sewing machine motor, wherein the sewing machine motor control unit includes the sewing machine Feedback control of the sewing machine motor is performed from a command value of the motor speed and the rotational speed detected by the sewing machine motor speed detection means.

According to the first aspect of the present invention, the sewing machine motor speed adjusting means adds or subtracts the sewing motor speed command value in accordance with the torque value of the cloth movement motor. That is, when the torque value of the cloth movement motor is large, that is, when the load of the cloth movement motor is large, the rotational speed of the sewing machine motor is decreased. As a result, the rotational speed of the sewing machine motor can be decreased before the cloth movement motor is overloaded and the operation of the cloth movement mechanism is delayed, so that the operation time of the cloth movement mechanism for each needle drop can be afforded. It becomes possible. And since the calculated torque value is a value that will be adopted for the control of the cloth movement motor from now on, unlike the case where the sewing machine motor is controlled based on the delay already generated in the cloth movement motor, more accurate sewing is performed. A sewing machine that can be used can be provided. That is, the sewing quality by the sewing machine is improved, and the reliability of the sewing machine is greatly improved.
Further, when the torque value of the cloth movement motor is small, that is, when the load of the cloth movement motor is small, the rotational speed of the sewing machine motor is increased by adding the command value of the sewing machine motor speed. As a result, when the load of the cloth movement motor is small and there is almost no possibility of delaying the operation of the cloth movement mechanism, the sewing speed can be increased by increasing the rotational speed of the sewing machine motor. Therefore, it is possible to perform sewing more quickly without reducing the sewing speed more than necessary.

According to the invention of claim 2, the cloth movement motor control means performs the PI control or PID control from the deviation between the command value of the cloth movement amount and the rotation angle of the cloth movement motor detected by the detection means, and calculates the torque value. calculate. As a result, it is possible to eliminate the occurrence of a residual deviation that cannot be sufficiently eliminated by the proportional operation (P control) in calculating the torque value required for the operation of the cloth movement motor. That is, it is possible to calculate the torque value of the cloth movement motor more suitably, and the operation of the cloth movement mechanism is performed with respect to the timing of the needle drop by increasing or decreasing the rotation speed of the sewing machine motor according to the torque value. The possibility of delay is further reduced. Therefore, a sewing machine that performs a more accurate sewing operation can be provided, and the reliability of the sewing machine is further improved.
Furthermore, in the case of PID control, even when a sudden change occurs in the load applied to the cloth movement motor, it is possible to quickly control the torque value for operating the cloth movement motor corresponding to the change. . That is, it is possible to calculate the torque value of the cloth movement motor more suitably, and the operation of the cloth movement mechanism is performed with respect to the timing of the needle drop by increasing or decreasing the rotation speed of the sewing machine motor according to the torque value. The possibility of delay is further reduced. Therefore, a sewing machine that performs a more accurate sewing operation can be provided, and the reliability of the sewing machine is further improved.

  According to a third aspect of the invention, the sewing machine motor speed adjusting means adds and subtracts the sewing motor speed command values according to the torque values of the two cloth movement motor control means, and calculates the two command values. The sewing machine motor is controlled by a smaller command value. As a result, the sewing machine motor is controlled so as to have a rotational speed of the sewing machine motor corresponding to the cloth movement motor having a larger load of the two cloth movement motors. Therefore, even if the sewing machine includes a cloth moving mechanism using two cloth moving motors, the possibility that the operation of the cloth moving mechanism is delayed with respect to the needle drop timing is further reduced. Therefore, a sewing machine that can perform more accurate sewing can be provided, the sewing quality of the sewing machine can be improved, and the reliability of the sewing machine can be further improved.

  According to the fourth aspect of the present invention, the sewing machine motor control means performs feedback control of the sewing machine motor from the command value of the sewing machine motor speed and the rotational speed detected by the sewing machine motor speed detection means. It is possible to drive at a rotational speed based on the command value of the sewing machine motor speed. Therefore, the sewing machine motor can follow the machine motor speed command value significantly, including the case where the machine motor speed command value is added or subtracted according to the load of the cloth movement motor, so that more accurate sewing can be performed. In addition, it is possible to provide a sewing machine that can perform sewing more quickly without reducing the sewing speed more than necessary.

(Overall configuration of one embodiment of the present invention)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The sewing machine 1 according to the present invention is provided with a cloth moving mechanism (not shown) against a vertical movement of a needle bar (not shown) that is provided on an arm portion (not shown) of the sewing machine 1 and moves up and down while holding a sewing needle. In the sewing machine that performs sewing by moving the sewing machine, a sewing machine motor 41 as a needle bar drive source and motors (X-axis motor 21 and Y-axis motor 23) as “cloth movement motors” that move the cloth movement mechanism are provided separately. It is a sewing machine.

FIG. 1 is a block diagram showing a configuration of a sewing machine 1 according to an embodiment of the present invention.
The sewing machine 1 includes an X-axis motor 21 that drives the cloth movement mechanism in one direction (hereinafter referred to as the X-axis direction) on a horizontal plane substantially parallel to the needle plate, a rotation angle A2 of the X-axis motor, and a motor phase θ2. An X-axis encoder 22 as a “detecting means” for detecting the movement, and a Y-axis motor 23 for driving the cloth moving mechanism in one direction (hereinafter referred to as the Y-axis direction) on a horizontal plane orthogonal to the X-axis direction and parallel to the needle plate. The Y-axis encoder 24 as a “detection means” for detecting the rotation angle A3 and the motor phase θ3 of the Y-axis motor, the sewing machine motor 41 for rotating the main shaft (not shown) of the sewing machine 1, and the rotation angle of the main shaft are detected. The main shaft encoder 42 that detects the rotation angle of the sewing machine motor 41, the main controller 10 that controls various processes of the sewing machine 1 and the operation of each part of the sewing machine 1, and the drive speed control of the sewing machine motor 41 are performed. A sewing machine motor speed control controller 30, an operation pedal 51 as a switch operated by an operator to switch the operation of the sewing machine 1, and an operation panel 52 as an interface for inputting / outputting various information of the sewing machine 1 are provided. Yes. The X-axis motor 21 and the Y-axis motor 23 are pulse motors, and the sewing machine motor 41 is an AC servo motor.

  Although not shown, the sewing machine 1 is provided in a cloth moving mechanism and a vertical movement mechanism that is provided so as to connect the needle bar and the main shaft, converts the rotary motion of the main shaft into a vertical motion and transmits it to the needle bar. The presser foot that holds the fabric, the thread clamp that holds the sewing thread until the stitches are formed after the start of sewing until the tension of the sewing thread remains constant, the thread trimmer that cuts the thread extending from the seam, and the thread trimmer And a wiper for receiving the sewing thread after the thread cutting operation by.

  The main controller 10 includes a CPU 11 that performs various processes of the sewing machine 1 and operation control of each unit of the sewing machine 1, a RAM 12 that stores data and parameters temporarily generated in the processes performed by the CPU 11, and various programs that the CPU 11 processes. And a ROM 13 for storing and holding data, and an EEPROM 14 for storing and holding sewing data 60 and various programs and data used for sewing work of the sewing machine in a rewritable manner. The EEPROM 14 stores sewing data 60 (see FIG. 2) including various parameters relating to the needle drop position, the total number of stitches, the sewing speed, and the sewing in the sewing operation. A plurality of sewing data 60 are stored according to a plurality of sewing patterns, and are selected by the operator via the operation panel 52. Thereafter, when a sewing operation is instructed by operating the operation pedal 51 by the operator, the CPU 11 of the main controller 10 is based on the rotational speed of the sewing machine motor 41 determined by the sewing speed of the selected sewing data 60. Then, the sewing machine motor 41 is driven via the sewing machine motor speed control controller 30. When the main shaft rotates by driving the sewing machine motor 41, it is converted into a vertical motion by the vertical motion mechanism and transmitted to the needle bar, and the needle bar moves up and down. Further, the CPU 11 of the main controller 10 drives the X-axis motor 21 and the Y-axis motor 23 based on the needle drop position and the total number of stitches of the selected sewing data 60 to move the cloth moving mechanism. Thus, the needle bar is moved up and down and the cloth moving mechanism is operated, and sewing is performed as is well known. That is, the sewing machine 1 is a so-called electronic cycle sewing machine.

  When holding the cloth on the cloth moving mechanism, the operator operates the operation pedal 51 to move the cloth presser up and down to hold the cloth on the presser foot. Also, immediately after the start of sewing, the thread can easily come off from the cloth, and when the seam is formed, the thread may be pulled from the previous seam and the seam may be loosened. Prevent this. Further, when the sewing thread extended from the cloth is cut when the sewing work is finished, the thread trimming is operated to cut the sewing thread. At this time, a cut piece of the cut sewing thread is generated, but the piece of the sewing thread is removed from the cloth by the operation of the wiper. The presser foot, the thread clamp, the thread trimmer, and the wiper are each driven by a motor (not shown) or an actuator (not shown), and the motor or actuator (not shown) is controlled by the main controller 10.

(Sewing data)
Next, the sewing data 60 will be described in detail. FIG. 2 is an explanatory diagram showing a table structure of the sewing data 60. As shown in FIG.
The sewing data 60 includes at least an X movement amount indicating the movement amount of the cloth movement mechanism in the X axis direction by the X axis motor 21 and a Y movement amount indicating a movement amount of the cloth movement mechanism in the Y axis direction by the Y axis motor 23. And spindle data indicating the number of revolutions of the spindle of the sewing machine 1.
The X movement amount and the Y movement amount are relative movement amount parameters with respect to the immediately preceding X movement amount and Y movement amount. That is, the X movement amount Xa and the Y movement amount Ya are movement amounts in the X axis direction and the Y axis direction of the cloth movement mechanism from a predetermined origin. The X movement amount Xb and the Y movement amount Yb are movement amounts in the X axis direction and the Y axis direction with respect to the position after the cloth movement mechanism moves the X movement amount Xa and the Y movement amount Ya.

The spindle rotation speed is a parameter for controlling the sewing machine motor 41 to the rotation speed of the spindle according to the X movement amount and the Y movement amount. That is, the sewing machine motor 41 is controlled by the sewing machine motor speed controller 30 so that the rotation speed of the main shaft when the cloth movement mechanism operates the X movement amount Xa and the Y movement amount Ya becomes the main shaft rotation speed Za. The details of the speed control of the sewing machine motor 41 by the sewing machine speed control controller 30 will be described later.
The spindle rotation speed is determined according to the corresponding X movement amount and Y movement amount. For example, when the cloth movement mechanism has to be moved greatly, the X movement amount, the Y movement amount, or both values become large. At this time, it is set so that the vertical movement speed of the needle bar is reduced by decreasing the spindle speed. As a result, the sewing machine 1 is controlled so as to ensure the movement time of the cloth moving mechanism that is performed between the previous needle drop occurring between the seams and the next needle drop. On the other hand, when the X movement amount and the Y movement amount are small, that is, when the movement amount of the cloth movement mechanism is small, the spindle rotational speed is set large. This increases the vertical movement speed of the needle bar and increases the sewing speed. That is, the sewing machine 1 is controlled so as to reduce the sewing speed when the movement amount of the cloth movement mechanism is large and to provide sufficient movement time of the cloth movement mechanism for each needle drop, and when the movement amount of the cloth movement mechanism is small, sewing is performed. It is controlled to increase the sewing work efficiency by increasing the speed. In this way, the sewing speed control for each needle drop and the operation of the cloth moving mechanism are synchronously controlled, and sewing by the sewing machine 1 is performed.

(Main controller)
Next, the main controller 10 will be described in detail. FIG. 3 is a block diagram showing the relationship between the configuration of the main controller 10 and the sewing machine motor speed control controller 30, and the configuration of the X-axis motor 21, Y-axis motor 23, sewing machine motor 41, and peripheral devices.
The main controller 10 includes command speed calculation means 71 for calculating a command speed V1 of the sewing machine motor 41 from the sewing data 60, and command position patterns P2 and P3 for driving the X-axis motor 21 and the Y-axis motor 23. Pattern calculation means 72, X-axis motor feedback control means 73 that performs feedback control in driving the X-axis motor, Y-axis motor feedback control means 74 that performs feedback control in driving the Y-axis motor, X-axis motor 21, Y Load calculating means 75 for calculating loads L2 and L3 generated in the shaft motor 23, and command speed for calculating a correction value C for correcting the command speed V1 based on the loads L2 and L3 calculated by the load calculating means 75 Correction value calculation means 76.

  The command speed calculation means 71 calculates a command speed V 1 for driving the sewing machine motor 41 based on the spindle speed of the sewing data 60 and outputs the command speed V 1 to the sewing machine motor speed controller 30. At this time, when the correction value C by the command speed correction value calculation means 76 is input, the command speed V1 is calculated after performing addition / subtraction with the correction value C. The correction value C will be described later.

  The command position pattern calculation means 72 calculates command position patterns P2 and P3 based on the X movement amount and the Y movement amount of the sewing data 60, and outputs them to the X axis motor feedback control means 73 and the Y axis motor feedback control means 74. . The timing at which the command position patterns P2 and P3 are output is the timing at which the rotation angle of the main shaft detected by the main shaft encoder 42 is the rotation angle at which the main shaft rotation angle A1 may operate the cloth movement mechanism. That is, the command position patterns P2 and P3 are output when the vertical movement position of the needle bar is the rotation angle of the main shaft in the operation from the previous needle dropout to the next needle dropout. That is, the X-axis motor 21 and the Y-axis motor 23 rotate fast when the main shaft rotation speed is high, and the X-axis motor 21 and Y-axis motor 23 rotate slowly when the main shaft rotation speed is low.

The X-axis motor feedback control means 73 performs feedback control based on the rotation angle of the X-axis motor 21 detected by the X-axis encoder 22 in the drive control of the X-axis motor 21. The Y-axis motor feedback control means 74 performs feedback control based on the rotation angle of the Y-axis motor 23 detected by the Y-axis encoder 24 in the drive control of the Y-axis motor 23.
FIG. 4 is a block diagram showing the configuration of the X-axis motor feedback control means 73 and the Y-axis motor feedback control means 74.
The X-axis motor feedback control means 73 (Y-axis motor feedback control means 74) includes a position calculation means 73a (74a) for calculating a command speed V2 (V3) of the X-axis motor 21 (Y-axis motor 23), and an X-axis motor. Of the X-axis motor 21 (Y-axis motor 22) detected by the speed control means 73c (74c) for calculating the required torque T2 (T3) of the 21 (Y-axis motor 23) and the X-axis encoder 22 (Y-axis encoder 24). Speed detection means 73d (74d) for calculating the detection speed S2 (S3) from the rotation angle A2 (A3), necessary torque T2 (T3) calculated by the speed control means 73c (74c), and the X-axis encoder 22 (Y-axis encoder) 24) Torque management means for calculating the output torque Te2 (Te3) of the X-axis motor 21 (Y-axis motor 23) from the motor phase θ2 (θ3) detected by 73e (74e).

  The position calculation means 73a (74a) is a deviation between the command position pattern P2 (P3) and the rotation angle A2 (A3) of the X-axis motor 21 (Y-axis motor 23) detected by the X-axis encoder 22 (Y-axis encoder 24). Based on the command speed V2 (X-axis motor 21 (Y-axis motor 23) for driving the X-axis motor 21 (Y-axis motor 23) at a rotational speed at which the X-axis motor 21 (Y-axis motor 23) has a rotational angle indicated by the command position pattern P2 (P3)). V3) is calculated.

The speed detection means 73d (74d) calculates the X-axis motor 21 (Y) from the deviation between the rotation angle A2 (A3) of the X-axis motor 21 (Y-axis motor 23) detected immediately before and the latest rotation angle A2 (A3). The detection speed S2 (S3), which is the actual driving speed of the shaft motor 23), is calculated and output to the speed control means 73c (74c).
The speed control means 73c (74c) is based on the deviation between the command speed V2 (V3) output from the position calculation means 73a (74a) and the detected speed S2 (S3), and the X-axis motor 21 (Y-axis motor 23). The required torque T2 (T3) is calculated and output to the torque management means 73e (74e) and the additional calculation means 75. Details of the calculation will be described later.

  The torque management means 73e (74e) detects the motor phase θ2 (θ3) detected by the X-axis encoder 22 (Y-axis encoder 24) in order to generate the necessary torque T2 (T3) output from the speed control means 73c (74c). Based on the above, the output phase is corrected, and in addition, the output current is adjusted, and control is performed so that the output torque Te2 (Te3) is output from the drive circuit 25 (26). This is a generally known pulse motor drive system.

  The drive circuit 25 (26) is a motor driver constituted by an FET or the like provided between the main controller 10 and the X-axis motor 21 (Y-axis motor 23). The drive circuit 25 (26) drives the X-axis motor 21 (Y-axis motor 23) based on the output torque Te2 (Te3).

The load calculation means 75 integrates the required torques T2 and T3 output from the speed control means 73c and 74c for a predetermined time, and calculates the load L2 of the X-axis motor 21 and the load L3 of the Y-axis motor 23, respectively. It outputs to the correction value calculation means 76.
The command speed correction value calculation means 76 calculates a correction value C for correcting the command speed V1 of the sewing machine motor 41 based on the loads L2 and L3 and outputs the correction value C to the command speed calculation means 71. The calculation of the correction value C will be described later.

  The above-described command speed calculation means 71, command position pattern calculation means 72, X-axis motor motor feedback control means 73, Y-axis motor feedback control means 74, load calculation means 75, and command speed correction value calculation means 76 are shown in FIG. It functions by the CPU 11 executing software for controlling each part of the sewing machine 1 stored in the ROM 13 of the sewing machine motor speed control controller 10 shown.

(Sewing motor speed controller)
Next, the sewing machine motor speed control controller 30 will be described in detail. As shown in FIG. 3, the sewing machine motor speed control controller 30 includes a sewing machine motor feedback control unit 80 that performs feedback control for controlling the sewing machine motor 41 based on a command value of the sewing machine motor speed.
FIG. 5 is a block diagram showing the configuration of the sewing machine motor feedback control means 80. The sewing motor feedback control means 80 includes a speed control means 81 for calculating the output torque T1 of the sewing motor 41, and a speed detection means 82 for calculating the detection speed S1 of the sewing motor 41 from the rotation angle A1 of the spindle detected by the spindle encoder 42. And.

The speed detecting means 82 detects the rotation angle of the sewing machine motor 41 from the rotation angle A1 of the spindle detected by the spindle encoder 42, and determines the rotation of the sewing machine motor 41 from the deviation of the rotation angle of the sewing machine motor 41 between the immediately preceding detection and the latest detection. A detection speed S 1 that is a rotation speed is calculated and output to the speed control means 81. That is, the spindle encoder 42 capable of detecting the rotation speed of the sewing machine motor 41 from the detected rotation angle A1 of the spindle functions as “sewing motor speed detection means”.
The speed control means 81 calculates the output torque T1 of the sewing machine motor 41 based on the deviation between the command speed V1 output from the command speed calculation means 71 and the detected speed S1, and outputs it to the drive circuit 43. Details of the calculation will be described later.
The above-mentioned sewing motor feedback control means 80 functions when the CPU 31 executes software for controlling the sewing motor 41 stored in the ROM 33 of the sewing motor speed controller 30 shown in FIG.

  The drive circuit 43 is a motor driver constituted by an FET or the like provided between the sewing machine motor speed control controller 30 and the sewing machine motor 41. The drive circuit 43 drives the sewing machine motor 41 by controlling the U, V, W phase and current based on the output torque T1. This is a generally known AC motor drive system.

(Driving control of sewing machine motor, X-axis motor and Y-axis motor based on sewing data)
Next, drive control of the sewing machine motor, the X-axis motor, and the Y-axis motor based on the sewing data 60 will be described in detail.
First, operation control between the sewing machine motor 41, the X-axis motor 21, and the Y-axis motor 23 based on the sewing data 60 will be described in detail. The command speed calculation means 71 of the main controller 10 outputs a command speed V1 of the sewing machine motor 41 based on the spindle speed of the sewing data 60 to the sewing motor speed controller 30. The sewing machine motor speed controller 30 drives the sewing machine motor 41 based on the command speed V1. When the sewing machine motor 41 operates, the main shaft encoder 42 detects the rotation angle A1 of the main shaft. At this time, the sewing machine motor feedback control means 80 of the sewing machine motor speed control controller 30 feedback-controls the sewing machine motor 41 based on the detection result of the spindle encoder 42.

  As shown in FIG. 5, the speed detecting means 82 of the sewing machine motor feedback control means 80 calculates the detected speed S1 of the sewing machine motor 41 from the rotational speed A1 of the main spindle detected by the main spindle encoder 42. The speed control means 81 calculates the output torque T1 of the sewing machine motor 41 from the deviation between the command speed V1 and the detected speed S1. At this time, the output torque T1 is calculated as a value proportional to the deviation between the command speed V1 and the detected speed S1 (proportional operation). Further, even after the sewing motor 41 is driven based on the output torque T1 output as a result of the proportional operation, the same kind of deviation (residual) remains between the command speed V1 and the detected speed S1 detected by the spindle encoder 42. When there is a deviation), correction according to the duration of the residual deviation is performed on the output torque T1 to the sewing machine motor 41 (integration operation). The “same type deviation” means a deviation when the detected speed S1 is still small with respect to the command speed V1 even after performing a proportional operation to increase the output torque T1 because the detected speed S1 is small with respect to the command speed V1. This is a deviation when the detected speed S1 is still higher than the command speed V1 even after the proportional operation for decreasing the output torque T1 is performed because the detected speed S1 is higher than the command speed V1.

  That is, the sewing machine motor speed controller 30 performs PI control based on the proportional action and the integral action based on the command speed V1 and the detected speed S1, and calculates the output torque T1 to the sewing machine motor 41. The output torque T1 to the sewing machine motor 41 is converted into a U, V, W phase control signal and a drive current value via the drive circuit 43 to drive the sewing machine motor 41. Thus, the sewing machine motor 41 is controlled to rotate the main shaft at a rotational speed based on the main shaft rotation speed of the sewing data 60. Therefore, the sewing machine motor speed control controller 30 functions as “sewing motor control means”.

The command position pattern calculation means 72 of the main controller 10 also converts the command position patterns P2 and P3 into X-axis motor feedback control means 73 and Y-axis motor feedback control means based on the rotation angle A1 of the spindle detected by the spindle encoder 42. Output to 74.
The X-axis motor feedback control means 73 (Y-axis motor feedback control means 74) controls the X-axis motor 21 (Y-axis motor 23) to be driven based on the command position pattern P2 (P3). At this time, the rotation angle A2 (A3) of the X-axis motor 21 (Y-axis motor 23) is detected by the X-axis encoder 22 (Y-axis encoder 24). At this time, the X-axis motor feedback control means 73 (Y-axis motor feedback control means 74) feedback-controls the X-axis motor 21 (Y-axis motor 22) based on the rotation angle A2 (A3).

As shown in FIG. 4, the X-axis motor feedback control means 73 (Y-axis motor feedback control means 74) is configured such that the position calculation means 73a (74a) first calculates the command position pattern P2 (P3) and the rotation angle A2 (A3). The command speed V2 (V3) is calculated from the deviation.
Next, the speed detection means 73d (74d) calculates the detection speed S2 (S3) based on the rotation angle A2 (A3). Thereafter, the speed control means 73c (74c) obtains the necessary torque T2 (T3) from the deviation between the command speed V2 (V3) and the detected speed S2 (S3). At this time, the required torque T2 (T3) is calculated as a value proportional to the deviation between the command speed V2 (V3) and the detected speed S2 (S3) (proportional operation). Further, the command speed V2 (V3) and the detected speed S2 (S3) after the driving of the X-axis motor 21 (Y-axis motor 23) performed based on the required torque T2 (T3) calculated as a result of the proportional operation. When there is a deviation of the same type (residual deviation) between the two, the correction according to the duration of the residual deviation is performed on the necessary torque T2 (T3) (integration operation). The “same kind of deviation” means that the detected speed S2 (S3) is smaller than the command speed V2 (V3), and therefore, after the proportional operation for increasing the necessary torque T2 (T3) is performed, the command speed V2 (V3) The deviation after the detected speed S2 (S3) is still small, or the command after performing the proportional action to lower the required torque T2 (T3) because the detected speed S2 (S3) is larger than the command speed V2 (V3). This is a deviation when the detected speed S2 (S3) is still larger than the speed V2 (V3).
That is, the main controller 10 performs PI control by proportional operation and integral operation based on the command speed V2 (V3) and the detected speed S2 (S3), and the required torque T2 of the X-axis motor 21 (Y-axis motor 23). (T3) is calculated.

Next, in order for the torque management means 73e (74e) to generate the required torque T2 (T3), output phase correction is performed based on the motor phase θ2 (θ3) detected by the X-axis encoder 22 (Y-axis encoder 24), In addition, the output current is adjusted to control the output torque Te2 (Te3) to be output from the drive circuit 25 (26). The drive circuit 25 (26) drives the X-axis motor 21 (Y-axis motor 23) based on the output torque Te2 (Te3). Thus, the X-axis motor 21 and the Y-axis motor 23 are controlled so as to have the movement amount of the cloth movement mechanism based on the X movement amount and the Y movement amount of the sewing data 60. Therefore, the main controller 10 functions as “cloth movement motor control means”.
Note that the feedback processing of the sewing machine motor 41, the X-axis motor 21 and the Y-axis motor 23 is performed once in an extremely short time (for example, 300 to 500 [μsec]) and is continued during the sewing operation by the sewing machine 1. Repeated.

Next, the load generated in the X-axis motor 21 and Y-axis motor 23 is calculated from the necessary torques T2 and T3 of the X-axis motor 21 and Y-axis motor 23, and addition / subtraction is added to the command speed V1 of the sewing machine motor 41. The mechanism will be described in detail.
The load calculation means 75 of the main controller 10 integrates the above-mentioned necessary torque T2 (T3) for a predetermined time and calculates it as the load L2 (L3) of the X-axis motor 21 (Y-axis motor 23) generated at the predetermined time. And output to the command speed correction value calculation means 76. The command speed correction value calculation means 76 calculates a value obtained by subtracting the load L2 (L3) from the predetermined threshold D and a predetermined gain as the command speed correction value C2 (C3) of the sewing machine motor 41. That is, when the load L2 (L3) is larger than the threshold value D, a negative command speed correction value C2 (C3) for decreasing the command speed V1 of the sewing machine motor 41 is calculated. On the other hand, when the load L2 (L3) is smaller than the threshold value D, a positive command speed correction value C2 (C3) for increasing the command speed V1 of the sewing machine motor 41 is calculated. When the threshold value D and the load L2 (L3) are the same, the command speed correction value C2 (C3) is zero.

  Further, the command speed correction value calculation means 76 compares the command speed correction value C2 and the command speed correction value C3, and outputs the smaller one to the command speed calculation means 71 as the correction value C of the command speed V1. The command speed calculation means 71 to which the correction value C is input adds or subtracts the correction value C when calculating the command speed V1 based on the spindle speed of the sewing data 60. That is, the sewing machine motor 41 is controlled so as to have a rotational speed, that is, a sewing speed, of the sewing motor 41 corresponding to the command speed correction value with the larger load of the X-axis motor 21 and the Y-axis motor 23 that move the cloth moving mechanism. Is done. Therefore, the main controller 10 functions as “sewing motor speed adjusting means”.

If the load L2 (L3) generated in the X-axis motor 21 (Y-axis motor 23) becomes too large, the actual operation of the X-axis motor 21 (Y-axis motor 23) with respect to the command position pattern P2 (P3). May not catch up, and the movement of the cloth moving mechanism performed by driving the X-axis motor 21 and the Y-axis motor 23 may be delayed. The threshold value D and the predetermined gain in the command speed correction value calculation means 76 are such that the load L2 is such that the X-axis motor 21 and the Y-axis motor 23 do not step out during the predetermined time during which the necessary torques T2 and T3 are integrated in the above-described processing. , L3. The threshold value D and the predetermined gain at this time vary depending on the pulse motor used in the X-axis motor 21 and the Y-axis motor 23 and the driver circuit that drives the pulse motor, and is optimal for the pulse motor and driver circuit. A threshold value D and a predetermined gain are set.
In addition, the operation response of the cloth movement mechanism is also changed by the pulse motor and the driver circuit. Therefore, the sewing data 60 is set with the X movement amount, the Y movement amount, and the spindle rotation speed in accordance with the sewing machine motor 41, the X axis motor 21, the Y axis motor 23 and the respective driver circuits employed in the sewing machine 1. .

(Effects of the sewing machine according to the above embodiment)
According to the above-described embodiment, when the necessary torques T2 and T3 of the X-axis motor 21 and the Y-axis motor 23 are large, that is, when the load on the X-axis motor 21 and the Y-axis motor 23 is large, the main controller 10 instructs The rotational speed of the sewing machine motor 41 is decreased by decreasing the speed V1. Accordingly, the rotation speed of the sewing machine motor 41 is decreased before the load of the X-axis motor 21 and the Y-axis motor 23 becomes too large to cause a delay in the operation of the cloth movement mechanism, and the operation time of the cloth movement mechanism for each needle drop. Can be provided, and the operating speeds of the X-axis motor 21 and the Y-axis motor 23 can be reduced to give a margin to the motor operation. Since the calculated necessary torques T2 and T3 are used when calculating the values of the output torques Te2 and Te3 that will be used for the control of the X-axis motor 21 and the Y-axis motor 23 from now on, they are already generated in the cloth movement motor. Unlike the case where the sewing machine motor is controlled based on the delay, the sewing machine 1 that can perform more accurate sewing can be provided. That is, the sewing quality by the sewing machine is improved, and the reliability of the sewing machine is greatly improved.
When the necessary torques T2 and T3 of the X-axis motor 21 and the Y-axis motor 23 are small, that is, when the load on the X-axis motor 21 and the Y-axis motor 23 is small, the main speed controller 10 sets the command speed V1 of the sewing machine motor 41. By increasing the rotational speed, the rotational speed of the sewing machine motor 41 is increased. As a result, when the loads on the X-axis motor 21 and the Y-axis motor 23 are small and there is little possibility that the operation of the cloth moving mechanism is delayed, the sewing speed can be increased by increasing the rotational speed of the sewing machine motor 41. . Therefore, sewing can be performed more promptly without reducing the sewing speed more than necessary.
Further, the threshold value D and the predetermined gain for calculating the command speed correction values C2 and C3 are based on the performance of the X-axis motor 21, the Y-axis motor 23, and the respective driver circuits so that the movement of the cloth movement mechanism is not delayed. The X movement amount, Y movement amount and spindle rotation speed of the sewing data 60 are also set based on the performances of the sewing machine motor 41, the X axis motor 21, the Y axis motor 23 and the respective driver circuits. . This eliminates the need for table data for associating a predetermined amount of rotation of the pulse motor with the required required time and table data for associating the predetermined time with the predetermined amount of rotation of the pulse motor. Therefore, the capacity of the storage device in which the table data is stored and the capacity of the RAM 12 for the control device to call up the table data at the time of sewing processing become unnecessary, and the sewing machine 1 can be provided at a lower cost. If there is room in the RAM 12 and ROM 13 storage areas of the main controller, table data that can call the command speed correction values C2 and C3 corresponding to the values of the loads L2 and L3 is provided to replace the above calculation. Also good.

Further, the main controller 10 performs PI control based on the deviation between the command position patterns P2 and P3 and the rotation angles of the X-axis motor 21 and the Y-axis motor 23 detected by the X-axis encoder 22 and the Y-axis encoder 24, and the required torque. T2 and T3 are calculated. As a result, it is possible to eliminate the occurrence of a residual deviation that cannot be sufficiently eliminated by the proportional operation (P control) in calculating the required torques T2 and T3. In other words, the necessary torques T2 and T3 can be calculated more suitably, and the operation of the cloth moving mechanism is performed at the needle drop timing by the acceleration / deceleration of the rotational speed of the sewing machine motor 41 according to the necessary torques T2 and T3. The possibility of being late is further reduced. Therefore, the sewing machine 1 that performs a more accurate sewing operation can be provided, and the reliability of the sewing machine is further improved.
Further, the sewing machine motor speed control controller 30 performs PI control from the deviation between the command speed V1 and the rotation angle of the main shaft detected by the main shaft encoder 42 to calculate the output torque T1. Thereby, it is possible to eliminate the occurrence of a residual deviation that cannot be sufficiently eliminated by the proportional operation (P control) in the calculation of the output torque T1. That is, it becomes possible to calculate the output torque T1 more suitably, and the rotation speed of the sewing machine motor 41 performed based on the output torque T1 is more suitably controlled.

  Further, the main controller 10 adds or subtracts the command speed V1 by decreasing the command speed V1 among the command speed correction values C2 and C3 calculated based on the necessary torques T2 and T3 to rotate the sewing machine motor 41. Control the speed. As a result, the rotational speed of the sewing machine motor 41 corresponding to the larger load of the X-axis motor 21 and the Y-axis motor 23 is obtained. Therefore, the possibility that the operation of the cloth moving mechanism performed by the X-axis motor 21 and the Y-axis motor 23 is delayed from the needle drop timing is further reduced. Therefore, the sewing machine 1 that can perform more accurate sewing can be provided, the sewing quality by the sewing machine is improved, and the reliability of the sewing machine is further improved.

  Further, the sewing machine motor speed control controller 30 calculates the output torque T1 from the command speed V1 of the sewing machine motor 41 and the detected speed S1 calculated by detecting the rotation angle of the spindle of the spindle encoder 42, and performs feedback control of the sewing machine motor 41. Therefore, the drive of the sewing machine motor 41 can be controlled so that the rotation of the main shaft is more reliably the rotational speed based on the main shaft rotation speed of the sewing data 60. Accordingly, the follow-up performance of the sewing machine motor is greatly improved, including the case where the rotational speed of the sewing machine motor 41 is added or subtracted according to the required torques T2 and T3 of the X-axis motor 21 and the Y-axis motor 23. In addition to performing sewing, it is possible to provide a sewing machine that can perform sewing more quickly without lowering the sewing speed more than necessary.

(Other)
Although the sewing machine 1 according to the above-described embodiment is an electronic cycle sewing machine, the present invention can be applied to all sewing machines that form a seam by driving a cloth feed motor in synchronization with the rotation of the sewing machine motor. For example, when applied to an electronic staggered sewing machine, the amount of movement of the feed dog that feeds the cloth is driven by the feed dog movement adjustment motor, and the correction value calculated from the load of the feed dog movement adjustment motor is fed back to the sewing machine motor. Sewing speed control similar to that in the above-described embodiment is possible.

In the above-described embodiment, the load calculating means 75 calculates the loads L2 and L3 from the necessary torque T2 of the X-axis motor 21 and the necessary torque T3 of the Y-axis motor 23. Individual load calculation means may be provided for each of the shaft motors 23 to calculate the loads L2 and L3.
The command speed correction value calculation means 76 calculates the command speed correction values C2 and C3 from the loads L2 and L3 and outputs the correction value C to the command speed calculation means 71. The X-axis motor 21 and the Y-axis motor Individual command speed correction value calculation means may be provided for each of the 23. In this case, the command speed calculation means adopts the smaller one of the command speed correction values C2 and C3 output from the individual command speed correction value calculation means as the correction value C.
In the embodiment described above, the command speed correction value calculation means 76 calculates the command speed correction values C2 and C3 from the loads L2 and L3, and outputs a smaller command speed correction value as the correction value C. The command speed correction value for a larger load may be calculated by comparing the loads L2 and L3, and the command speed correction value may be adopted as the correction value C.

  Further, apart from the calculation of the load on the X-axis motor 21 (Y-axis motor 23) by integrating the required torque T2 (T3) for the predetermined time described above, the required torque T2 (T3) for a shorter time different from the predetermined time. It is also possible to calculate the command speed correction value by calculating the load based on the integration, and calculate the correction value C based on the smallest value compared with the command speed correction values C2 and C3. Further, the command speed correction value is calculated from the necessary torques T2 and T3 generated every time without performing integration, and the correction value C is calculated based on the smallest value compared with the command speed correction values C2 and C3. Also good. In this case, it is set so that addition / subtraction to the command speed V1 is performed using a command speed correction value that most reduces the command speed V1. In the case of such a configuration, the rotational speed of the sewing machine motor 41 can be significantly reduced when a large load is momentarily generated in the X-axis motor 21 (Y-axis motor 23). ), The possibility of delay in movement of the cloth moving mechanism is further reduced even when a large load is instantaneously generated.

Further, the command position pattern calculation means controls the rotation angles of the X-axis motor 21 and the Y-axis motor 23 based on the rotation angle A1 of the main shaft, but only the operation timing is determined from the rotation angle A1 of the main shaft. The rotation speed may be fixedly determined by the amount of rotation. In this case, the X-axis and Y-axis motors operate with a delay relative to the command from the command position pattern calculation means, but the needle bar operation due to the rotation of the main shaft operates without a delay, which adversely affects sewing. Will not affect.
Further, PI control is performed in the drive control of the sewing machine motor 41 and the drive control of the X-axis motor 21 and the Y-axis motor 23, but the PI control may be replaced with PID control. In the case of PID control, in addition to the above-described PI control processing, an input proportional to the differential of the deviation between the command value and the detected value is performed (differentiation operation). In the case of PID control, in addition to the effect of PI control, even when a sudden change occurs in the load applied to the X-axis motor 21 and the Y-axis motor 23, the necessary torques T2 and T3 corresponding to the change are promptly corrected. It becomes possible. In other words, the necessary torques T2 and T3 can be calculated more suitably, and the operation of the cloth moving mechanism is performed at the needle drop timing by the acceleration / deceleration of the rotational speed of the sewing machine motor 41 according to the necessary torques T2 and T3. The possibility of being late is further reduced. Therefore, the sewing machine 1 that performs a more accurate sewing operation can be provided, and the reliability of the sewing machine is further improved.

The sewing machine motor 41 is an AC servo motor, and the X-axis motor 21 and the Y-axis motor 23 are pulse motors. However, these may be any motors capable of PI control or PID control.
Further, the feedback processing time (for example, 300 to 500 [μsec]) for the sewing machine motor 41, the X-axis motor 21 and the Y-axis motor 23 is merely an example, and it is needless to say that the time may be different. Yes.

It is a block diagram which shows the structure of the sewing machine which is one Embodiment of this invention. It is explanatory drawing which shows the table structure of sewing data. It is a block diagram which shows the relationship between the structure of a main controller and a sewing machine motor speed control controller, and the structure of a X-axis motor, a Y-axis motor, the sewing machine motor 41, and its peripheral device. It is a block diagram which shows the structure of a X-axis motor feedback control means and a Y-axis motor feedback control means. It is a block diagram which shows the structure of a sewing machine motor feedback control means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Main controller 21 X-axis motor 22 X-axis encoder 23 Y-axis motor 24 Y-axis encoder 30 Sewing motor speed control controller 41 Sewing motor 42 Main-axis encoder 60 Sewing data 71 Command speed calculation means 73 X-axis motor feedback control means 74 Y-axis Motor feedback control means 75 Load calculation means 76 Command speed correction value calculation means 80 Sewing motor feedback control means

Claims (4)

A needle bar provided to be able to move up and down while holding the sewing needle;
A vertical movement mechanism that connects the needle bar and the main shaft of the sewing machine to convert the rotary motion into a vertical motion;
A sewing machine motor that rotates the spindle;
A cloth moving mechanism that holds the cloth and moves the cloth along a horizontal plane perpendicular to the vertical movement of the needle bar;
A cloth movement motor for driving the cloth movement mechanism,
In a sewing machine in which the cloth moving mechanism moves the cloth and performs sewing with respect to the vertical movement of the needle bar,
Detecting means for detecting a rotation angle of the cloth movement motor;
Cloth movement motor control means for calculating the output torque of the cloth movement motor from the command value of the cloth movement amount and the rotation angle of the cloth movement motor detected by the detection means and performing feedback control of the cloth movement motor;
A sewing machine motor control means for controlling the sewing machine motor based on a command value of the sewing machine motor speed,
A sewing machine speed adjusting means for adding / subtracting a command value of the sewing machine motor speed according to a torque value of the cloth moving motor calculated by the cloth moving motor control means.   The cloth movement motor control means calculates a torque value by performing PI control or PID control from a deviation between a command value of the cloth movement amount and a rotation angle of the cloth movement motor detected by the detection means. The sewing machine according to claim 1. The cloth movement mechanism has two cloth movement motors that drive in two directions;
The two detection means respectively provided in the two cloth movement motors;
Two cloth movement motor control means provided respectively on the two cloth movement motors,
The sewing motor speed adjusting means is based on a smaller torque value or command value among the torque values of the two cloth movement motor control means or two command values of the sewing machine motor speed calculated according to the torque value. The sewing machine according to claim 1, wherein the sewing machine motor is controlled. A sewing machine motor speed detecting means for detecting the rotational speed of the sewing machine motor;
The sewing machine motor control means performs feedback control of the sewing machine motor from a command value of the sewing machine motor speed and a rotation speed detected by the sewing machine motor speed detection means. The sewing machine according to Item.

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