JP2006304992A - Presser foot apparatus for sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To move a presser foot member at a position of an optional height according to its manipulated variable, to move the presser foot member at a speed according to the operation speed of an operation body, and to instruct starting of sewing easily. <P>SOLUTION: When a step pedal is stepped from a neutral area to an operation area, detected voltages A and B of a potentiometer for a portion of twice are read every prescribed minute time to obtain the effective stepping amount of the step pedal (S11 to S13). Next, a target height position of lowering a presser foot member according to the obtained stepping amount and a lowering speed according to the stepping speed of the step pedal are calculated (S18), and a presser foot motor is driven directly to the position of the target height at the obtained lowering speed (S1 to S9). When the step pedal is step-operated to the sewing area (S20:Yes), starting of a sewing machine motor (starting of sewing) is instructed (S22). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cloth presser device for a sewing machine, and more particularly to a cloth presser member that presses a work cloth toward and away from the work cloth in accordance with an operation amount of an operating body.

  Conventionally, when sewing is performed on a work cloth by a sewing machine, the sewing is performed in a state where the work cloth is pressed by a cloth pressing member. In particular, in an industrial sewing machine, in order to increase work efficiency, an operator can operate an electric actuator by operating a knee pad or a foot pedal with his / her knee or foot without using his / her hand. The presser foot can be moved up and down, and the start of sewing can be commanded.

  For example, a presser foot lifting device for a sewing machine described in Patent Document 1 includes a presser bar having a presser foot, a rotation lever, an operating mechanism including a connecting rod, an operating rod, and the like, and a presser foot by operating this operating mechanism. A servo solenoid that raises and lowers the foot, a potentiometer that detects the amount of operation of the operating body, a potentiometer that detects the amount of movement of the servo solenoid, etc. are provided, and the servo solenoid is driven according to the amount of operation of the operating body by the operator's knee, The height position of the foot can be moved to an arbitrary height, and the start of sewing is instructed by stepping on a separate foot-operated operation pedal.

In the sewing machine described in Patent Document 2, the presser is driven up and down by a presser lifting motor, and when the presser height setting pedal is not depressed, the presser is positioned at the maximum height position set in advance by the operation panel. When the presser foot height setting pedal is depressed in one step, the presser foot is lowered to the minimum height position, and when the presser foot height setting pedal is depressed in two steps, sewing is started.
Japanese Patent Laid-Open No. 62-101287 (pages 2 to 5, FIGS. 1 and 7) JP 2003-326017 A (pages 2 and 3, FIGS. 2 and 5)

  In the presser foot lifting device of the sewing machine described in Patent Document 1, it is configured so that the height position of the presser foot can be adjusted to an arbitrary height according to the operation amount of the operating body by the operator. In order to start sewing, another operation pedal must be stepped on with a foot, which is inferior in operability, and an additional operation pedal is provided in addition to the operation body, which increases the cost, presser lifting operation and sewing There are problems such as complication of the starting operation, and even if the operating speed of the operating body is increased, the vertical movement speed of the presser foot does not change and the workability is inferior.

  The sewing machine described in Patent Document 2 is configured so that the height position of the presser can be changed with only one presser height setting pedal. However, when changing the maximum height position of the presser, Must be set from the operation panel each time, lack of operability, the presser can not be stopped at any position between the set maximum height position and the minimum height position, presser height setting Even if the operating speed of the pedal is increased, the vertical movement speed of the presser does not change, and there are problems such as poor workability.

  A cloth presser device for a sewing machine according to claim 1 is provided with a cloth presser motor that moves a cloth presser member that presses the work cloth closer to or away from the work cloth, and an operating body that commands start / stop of the sewing machine motor. In the cloth presser device, the operation amount detecting means for detecting the operation amount of the operating body, and the presser foot motor to move the presser foot member to a position corresponding to the operation amount of the operating body detected by the operation amount detecting means. And a motor control means for controlling the cloth presser motor so as to move the cloth presser member at a speed corresponding to the operation speed of the operating body.

  When the operator operates the operating body at the start of sewing, the operation amount is detected by the operation amount detecting means. Therefore, the presser foot motor is controlled so as to move the presser foot member to a position corresponding to the operation amount, and the presser foot motor is controlled so that the presser foot member moves at a speed corresponding to the operation speed of the operating body. Is done.

  A cloth presser device for a sewing machine according to a second aspect of the present invention is the sewing machine cloth presser device according to the first aspect, wherein the operation amount detection means includes a neutral region on the operation start side, an operation region following the neutral region, and a sewing region following the operation region. The motor control means controls the cloth presser motor so as to move the cloth presser member after the operation body enters the operation region.

  According to a third aspect of the present invention, there is provided a sewing machine presser device according to the first or second aspect, further comprising an activation control unit that activates a sewing machine motor when a sewing region is detected by the operation amount detection unit.

  According to a fourth aspect of the present invention, there is provided a sewing machine presser device according to any one of the first to third aspects, wherein the presser foot motor comprises a stepping motor, and the motor control means includes an encoder for detecting a rotation angle of the stepping motor. .

  A sewing machine presser device according to a fifth aspect of the present invention is the sewing machine presser device according to any one of the first to fourth aspects, wherein an arbitrary height position in the vertical movement locus of the vertical presser member that is moved up and down is set as the lift position of the presser foot member The motor control means includes drive amount changing means for changing the drive amount of the cloth presser motor in accordance with the distance between the raised position and the lowered position where the cloth presser member presses the work cloth.

  According to the first aspect of the present invention, the presser foot of the sewing machine includes the presser foot motor that moves the presser foot member that presses the work cloth closer to or away from the work cloth, and the operating body that commands start / stop of the sewing machine motor. In the apparatus, since the operation amount detecting means and the motor control means are provided, the cloth presser member can be moved to an arbitrary height position according to the operation amount of the operation body operated by the operator. Since the member can be moved at a speed according to the operation speed of the operating body, the movement operation of the presser member can be simplified, and the workability of the sewing work can be improved.

  According to a second aspect of the present invention, the operation amount detection means is configured to be able to detect a neutral region on the operation start side, an operation region following the neutral region, and a sewing region following the operation region. Since the means controls the presser foot motor so that the presser foot member is moved after the operation of the operating tool enters the operating region, a small amount of operation due to vibration of the operating tool is performed in the neutral region on the operation start side. The amount can be invalidated to prevent so-called malfunction. When the operating body is sufficiently operated to the operating region, the operation amount is validated, and the cloth presser member can be actually moved according to the operation amount. Other effects similar to those of the first aspect are obtained.

  According to the third aspect of the present invention, since the sewing machine motor is started when the sewing area is detected by the operation amount detecting means, the operation body is operated only from the operating area to the sewing area. The sewing start can be commanded in conjunction with the pressering operation by the presser member, and the operability of the sewing start operation can be greatly improved. Other effects similar to those of the first or second aspect are achieved.

  According to the invention of claim 4, since the cloth presser motor comprises a stepping motor and the motor control means has an encoder for detecting the rotation angle of the stepping motor, it is output from the encoder when driving the cloth presser motor. By employing the encoder signal for feedback control, it is possible to reliably and accurately recognize the presence or absence of synchronization displacement or step-out of the presser foot motor. Other effects similar to those of any one of claims 1 to 3 are provided.

  According to the fifth aspect of the present invention, there is provided setting means for setting an arbitrary height position in the up-and-down movement locus of the presser member that is moved up and down as the lift position of the presser member, and the motor control means includes the lift position and the presser foot. Since there is a drive amount change means that changes the drive amount of the presser foot motor according to the distance from the lowered position where the member presses the work cloth, the lift position of the presser foot member according to the thickness of the work cloth used for sewing Can be set arbitrarily, so that the work efficiency can be greatly improved. Moreover, since the driving amount of the presser foot motor can be changed, the set ascending position can be reflected in the presser foot lifting control. Other effects similar to those of any one of claims 1 to 4 can be achieved.

  As an example, the automatic pattern sewing machine (cycle sewing machine) in this embodiment can raise and lower the presser foot at an arbitrary height position according to the stepping amount of the foot pedal and at a moving speed according to the stepping speed. Sewing can be started in conjunction with the stepping operation.

  As shown in FIGS. 1 and 2, the automatic pattern sewing machine 1 is placed on a work table 8, and includes a bed portion 2, a pedestal portion 5 erected upward from a rear end portion of the bed portion 2, and The arm portion 6 extends forward from the upper end portion of the pedestal portion 5 so as to face the bed portion 2.

  A sewing machine motor 9 for driving the sewing needle 11 up and down through the needle bar 10 and a driving force transmission mechanism for transmitting the driving force of the sewing machine motor 9 to the sewing needle 11 through the main shaft are provided on the pedestal 5 and arm 6. However, since it is a known technique, a detailed description thereof is omitted here. A needle bar vertical movement mechanism for moving the needle bar 10 up and down is provided inside the head 7 which is the front end of the arm unit 6.

  The bed portion 2 includes a bed main body portion 3 on which a pedestal column portion 5 is erected and a cylinder bed portion 4 extending forward from the bed main body portion 3. Although not shown in the figure, the bed 2 is provided with a cloth presser mechanism 20, a needle plate 12 and a feed base 13, which will be described later, and a cloth receiving plate 16 having a rear end connected to the feed base 13 in the front-rear direction (Y ) And a cloth feed mechanism (not shown) that moves in the left-right direction (X direction), a vertical shuttle 14 that forms a pattern stitch by adjusting the vertical movement of the sewing needle 11, and a rotational driving force from the sewing machine motor 9. Are provided with a lower shaft 15 that transmits the thread to the vertical hook 14, a thread trimming mechanism (not shown) that cuts the upper thread and the lower thread at the end of sewing, and the like.

  Next, the presser foot device 20 that moves the presser foot member 24 up and down will be described. The presser foot device 20 is provided on a feed base 13 disposed on the upper surface of the bed 2, and is moved together with the feed base 13 in the front-rear direction and the left-right direction.

  As shown in FIGS. 1 to 3, the base end portion (rear end portion) of the presser arm 21 that is curved and cantilevered in a side view is fixed to the upper surface of the feed base 13, and A presser attachment portion 21a for supporting the rectangular frame-shaped cloth presser member 24 is formed at the distal end portion. A pivot shaft 22 in the left-right direction is fixed to the center portion of the presser arm 21 in the front-rear direction, and presser arm levers 23 extending in the front-rear direction are provided on the left and right sides of the presser arm 21, respectively. Is pivotally supported by the pivot shaft 22 at a substantially central portion in the front-rear direction.

  A connecting portion 241 of a cloth pressing member 24 is supported on the presser attachment portion 21a so as to be movable up and down. An engagement hole is formed in the connecting portion 214 of the presser foot member 24, and the tip end portion of the presser arm lever 23 is inserted into the engagement hole from the rear, and the presser foot member 24 and the presser arm lever 23 are connected. Yes. The rear end portion of the presser arm lever 23 is rotatably connected to the upper end portion of the spring guide shaft 25. The lower end portion of the spring guide shaft 25 is supported by the spring receiving member 26 of the presser arm 21 so as to be slidable in the vertical direction. The compression coil spring (pressing biasing means) 27 is externally mounted on the spring guide shaft 25 over the spring receiving portion of the spring guide shaft 25 and the spring receiving portion of the spring receiving member 26.

  Therefore, the pair of presser arm levers 23 are elastically urged counterclockwise via the pivot shaft 22 in FIGS. 1 and 3 by the spring force of the compression coil spring 27, and the cloth presser members 24 are lowered. In this position, the upper surface of the needle plate 12 is pressed through the cloth receiving plate 16. On the other hand, presser operation plates 28 are respectively fixed by bolts 29 on the left and right sides of the presser arm lever 23 on the rear side of the pivot shaft 22. The use of the cloth receiving plate 16 is optional, and when not used, the cloth holding member 24 is biased toward the upper surface of the needle plate 12.

  Therefore, as will be described later, by pressing the presser operation plate 28 downward by the downward movement of the vertical movement member 47, the pair of left and right presser arm levers 23 resists the spring force of the compression coil spring 27, and the pivot shaft Since 22 is rotated clockwise about the rotation fulcrum, the presser foot 24 is raised to the raised position above the needle plate 12. Here, the presser operation plate 28 is always in contact with the lower end surface of the vertical movement member 47 by the spring force of the compression coil spring 27, and a gap is generated between the vertical movement member 47 and the presser operation plate 28. Absent.

  As shown in FIGS. 2 to 3, a substantially U-shaped fixed frame 31 is attached to the frame inside a cover member 30 provided so as to cover the rear side of the pedestal 5, and the fixed frame A cloth presser motor 32 is fixed to the right side wall 31 a of 31, and a drive gear 33 is fixed to a drive shaft of the cloth presser motor 32. In this case, the connecting wall portion of the fixed frame 31 is on the lower side, and the rear side and the upper side are open.

  One cam support shaft 34 in the left-right direction is rotatably supported by the right side wall portion 31a and the left side wall portion 31b of the fixed frame 31. The cam support shaft 34 meshes with the drive gear 33 from the right side. The driven gear 35 and the presser foot cam 36 that performs the presser foot operation are arranged in this order, and are fixed with fixing screws.

  However, the driven gear 35 and the cloth presser cam 36 are integrally formed, and are fixed to the cam support shaft 34 by a fixing screw so that the fixing can be released.

  As shown in FIG. 3, a pivot shaft 40 in the left-right direction is fixed to the upper end portions of the right side wall portion 31 a and the left side wall portion 31 b of the fixed frame 31, and the pivot shaft 40 is L-shaped in a side view. The first presser lever 41 is pivotally supported, and a presser roller 42 capable of coming into contact with the cam surface of the presser foot cam 36 from the front is connected to the lower end of the drive side lever portion 41a of the first presser lever 41. Has been. The rear end portion of the presser linkage 43 in the front-rear direction is connected to the driven side lever portion 41 b of the first presser lever 41, and the front end portion of the presser linkage 43 is fixed to the frame of the arm portion 6. It is connected with the drive side lever part 45a of the L-shaped 2nd presser lever 45 pivotally supported by this.

  A pin 46 is fixed to the driven lever portion 45b of the second presser lever 45, and a pin is attached to a square piece 48 that can slide back and forth on a vertical movement member 47 pivotally supported on the frame of the arm portion 6. 46 is connected, and a horizontal plate that pushes down the presser operation plate 28 is provided at the lower end of the vertical movement member 47. Here, a tension coil spring 49 is interposed between the driven lever portion 41 b of the first presser lever 41 and the frame, and the presser roller 42 is always pressed against the cam surface of the presser foot cam 36.

  Therefore, when the presser foot motor 32 is driven to rotate in the forward direction, the presser roller 42 moves through the curved operating cam portion of the presser foot cam 36, so that the cam support shaft 34 is driven clockwise in FIG. The first presser lever 41 is rotated counterclockwise, the second presser lever 45 is rotated clockwise through the presser linkage 43, and the vertical movement member 47 is lifted to release the presser operation plate 28 from being pressed down. Therefore, the presser arm lever 23 rotates counterclockwise, and the presser foot member 24 engaged with the distal end portion of the presser arm lever 23 moves to a lowered position that is lowered by a predetermined distance from the raised position.

  Next, as shown in FIG. 1, the box B is fixed below the work table 8, and a pivot lever 52 is pivotally supported on a pivot shaft 51 fixed to the box B. The lever 52 is always urged counterclockwise by the spring force of the tension spring 53. However, the rotation lever 52 is brought into contact with the stopper 54 immediately above from the lower side, and the rotation position in the counterclockwise direction is restricted. Further, the drive shaft of the potentiometer 55 is coupled to the proximal end portion of the rotation lever 52 so as to be rotatable in synchronization with the rotation lever 52.

  A distal end portion of the rotation lever 52 is connected to an opening / closing plate 57a of a foot pedal 57 (which corresponds to an operating body) placed on the floor surface via a connecting rod 56. However, the open / close plate 57a is opened to the open position shown in FIG. 1 by a compression spring (not shown). When the operator steps on the opening / closing plate 57a with his / her foot, the rotation lever 52 rotates through the connecting rod 56 and the drive shaft of the potentiometer 55 rotates at the same time, so that the potentiometer 55 responds to the rotation angle of the drive shaft. The detected voltage is output to the control device 60 described later.

  Next, the control system of the automatic pattern sewing machine M will be described based on the block diagram of FIG. The control device 60 includes an input / output interface 61, a CPU 62, a ROM 63, a computer including a RAM 64, a flash memory 65, and the like, drive circuits 68 to 71, and the like. Here, the operation panel 66 will be briefly described.

  As shown in FIG. 5, on the operation panel 66, a reset key 66a, a height position setting key 66b for arbitrarily setting the raised position of the presser member 24, various function keys 66c to 66f, and a numerical value to be set are increased. An up key 66g, a down key 66h for decreasing a set numerical value, other display lamps, a small display, and the like are provided.

  The input / output interface 61 includes an operation panel 66, a drive circuit 68 for the sewing machine motor 9, and an X motor 72 for driving the feed base 13 in the X direction via an X direction drive mechanism provided in the cloth feeding device. Drive circuit 69, a drive circuit 70 for the Y motor 73 that drives the feed table 13 in the Y direction via a Y direction drive mechanism provided in the cloth feeding device, and a drive circuit for the cloth presser motor 32 71, an X direction origin sensor 74 for origin setting provided in the X direction drive mechanism, a Y direction origin sensor 75 for origin setting provided in the Y direction drive mechanism, and the like are connected.

  Incidentally, an N encoder 32E, which is a rotary encoder, is attached to the drive shaft of the presser foot motor 32. The N encoder 32E is for detecting the actual amount of rotation of the presser foot motor 32. The N encoder 32E is fixed to be rotatable together with the drive shaft and has slits formed at appropriate intervals in the circumferential direction, a light emitting portion and a light receiving portion. Having a detector.

  Therefore, in the N encoder 32E, when the light emitted from the light emitting unit passes through the slit of the disk and is detected by the light receiving unit, an encoder signal relating to movement in the height direction is output to the input / output interface 61, The rotation angle of the drive shaft of the presser motor 32 is detected. An X encoder 72E and a Y encoder 73E, which are rotary encoders configured similarly to the N encoder 32E, are also attached to the drive shafts of the X motor 72 and the Y motor 73, respectively.

  In this case, the presser foot motor 32 is a stepping motor, and its resolution is, for example, 800 pulses. The N encoder 32E outputs 800 encoder signals by one rotation of the presser foot motor 32. Therefore, when controlling the presser foot motor 32, the encoder signal output from the N encoder 32E is used for feedback control, so that the presser foot motor 32 can be reliably and accurately checked for synchronization shift and step-out. Can be recognized.

  In the ROM 63, various drive mechanisms are driven and controlled, and a sewing control program for various patterns, a control program for raising and lowering the presser member specific to the present application, which will be described later, and the like are stored in advance. Further, the ROM 63 stores setting data of the driving speed table T1 shown in FIG. 6 and a detection voltage pulse number table T2 shown in FIG.

  The drive speed table T1 stores information that defines a drive speed (moving speed of the presser member 24) in which a drive pulse number for driving the presser member 24 is associated with a drive frequency for driving the presser motor 32. Has been.

  Further, the detected voltage pulse number table T2 is outputted from the potentiometer 55 in correspondence with the neutral region on the stepping start side of the foot pedal 57, the operation region following this neutral region, and the sewing region following this operation region. Drive amount information that associates the detected voltage value (V) with the drive conversion value (height position information of the presser foot member 24) based on the detected voltage value and the number of drive pulses for driving the presser foot motor 32 is provided. Stored.

  Here, the drive conversion value is height position information for obtaining the number of drive pulses obtained by multiplying the detection voltage value by a predetermined coefficient K. Therefore, when the drive conversion value is within the range of “75 to 99”, the presser member 24 corresponds to the neutral region, and when the drive conversion value is within the range of “100 to 165”, The presser foot member 24 corresponds to the operation region, and when the drive conversion value is within the range of “166 to 170”, the presser foot member 24 corresponds to the sewing region.

  The flash memory 65 is an electrically rewritable nonvolatile memory, and can store a plurality of raised positions of the presser foot member 24 set using the height position setting key 66b of the operation panel 66. . The RAM 64 is provided not only with a sewing data memory for storing sewing data to be used for sewing, but also with various memories, pointers, counters, and the like for storing calculation results calculated by the CPU 62 as necessary.

  Next, the presser foot lifting control routine executed by the automatic pattern sewing machine M control device will be described with reference to the flowchart of FIG. However, the symbol Si (i = 11, 12, 13,...) In the figure is each step.

  By the way, prior to the start of this control, the operator can arbitrarily set the raising position of the presser foot member 24 in advance using the operation panel 66 as necessary. Therefore, first, a routine of the ascending position setting control will be described based on the flowchart of FIG. It should be noted that the arbitrary setting of the raised position of the cloth presser member 24 is not an essential process. That is, for simplification of the apparatus, it is possible to fix the position in advance rather than arbitrarily design the rising position.

  When the height position setting key 66b of the operation panel 66 is operated, the height position setting mode is set and this control is started. First, when the set lift position of the presser foot member 24 is stored in the flash memory 65, the set lift position data set is read (S41), and the presser foot motor is based on the lift position data. 32 is driven, and the presser foot member 24 is moved to the set raised position (S42).

  Next, the operator increases the height of the presser foot member 24 when it is lower than the desired position, and adjusts the height position lower when the height position of the presser foot member 24 is higher than the desired position. To do. In other words, when the up key 66g is operated (S43: Yes, S44: Yes), the control set ascending position is increased by a predetermined amount (for example, an amount control corresponding to about 1 mm) (S45). The presser foot 24 is moved upward according to the increase (S46).

  On the other hand, when the down key 66h is operated (S43: Yes, S47: Yes), the control set ascending position is decreased by a predetermined amount (for example, an amount control corresponding to about 1 mm) (S48). The presser foot member 24 is moved downward according to the decrease (S49). When the height position setting key is finally operated (S43: Yes, S50: Yes), the set ascending position stored in the flash memory 65 is updated (S51), and the newly set ascending position is also updated. In accordance with the distance between the position and the lowering position for pressing the work cloth W, the driving amount of the cloth pressing motor 32 is changed to the set range of the rising position and the lowering position (S52), and this control is finished.

  For example, in the detection voltage pulse number table T2 (see FIG. 7), when the set rising position is set to “23.1 mm”, this height position corresponds to the number of “36” drive pulses, so that 36 pulses The minute is shifted and the driving amount of the presser foot motor 32 until the start of sewing is changed from 360 pulses to 360 pulses.

  Next, the presser foot lifting control will be described. However, a boundary voltage value C to be described later is a voltage value (for example, “2.00 V” based on FIG. 10) in contact with the operation region of the neutral region. It is assumed that it has already moved to the raised position set by the raised position setting control.

  When this control is started, the detection voltage output from the potentiometer 55 is first read as “detection voltage A” (S11). Thereafter, when a predetermined minute time (for example, several tens of milliseconds) has elapsed (S12: Yes), the detection voltage output from the potentiometer 55 is read again as "detection voltage B" (S13).

  Next, when the detection voltage B belongs to the neutral region (S14: Yes) and the detection voltage A also belongs to the neutral region (S25: Yes), the lowering operation of the presser foot member 24 is performed. Instead, S13 and subsequent steps are executed. However, when the detection voltage B does not belong to the neutral region, that is, belongs to the operation region (S14: No), and when the detection voltage A belongs to the neutral region (S15: Yes), the detection voltage A has a boundary voltage value. C is written (S16), and the process proceeds to S17.

  On the other hand, when the detection voltage B belongs to the neutral region (S14: Yes) and the detection voltage A does not belong to the neutral region, that is, belongs to the operation region (S25: No), the boundary voltage value is included in the detection voltage B. C is written (S26), and the process proceeds to S17. Furthermore, when the detection voltage B does not belong to the neutral region (belongs to the operation region) (S14: Yes), and when the detection voltage A does not belong to the neutral region (belongs to the operation region) (S15: No) To S17.

  Therefore, an increase in the detection voltage B with respect to the detection voltage A, that is, an increase in the drive conversion value B corresponding to the detection voltage B with respect to the drive conversion value A corresponding to the detection voltage A is a reference value (for example, drive conversion). If the value is smaller than “3”), that is, if there is a possibility that the detection voltage B has increased due to the vibration of the foot pedal 57 (S17: No), the increase in the drive conversion value is invalidated and the process returns to S13. , S13 and subsequent steps are repeatedly executed.

  Here, when the amount of depression of the foot pedal 57 by the operator decreases, that is, when the presser foot member 24 is raised, the detection voltage B becomes smaller than the detection voltage A. In this case, since it is not an increase of the detection voltage B with respect to the detection voltage A, it is obtained as an absolute value.

  However, when the increment of the drive conversion value B with respect to the drive conversion value A is greater than or equal to the reference value, and the step pedal 57 is depressed by the operator (S17: Yes), these detected voltages A ( The driving speed of the presser foot motor 32 (speed of raising or lowering the presser foot member 24) corresponding to the voltage difference between the drive conversion value A) and the detection voltage B (driving conversion value B), and the target of the presser foot member 24 The height position is calculated (S18).

  That is, based on the detection voltage pulse number table T2 of FIG. 7, the drive pulse number A corresponding to the detection voltage A (drive conversion value A) and the drive pulse number corresponding to the detection voltage B (drive conversion value B). B is obtained, and an actual drive pulse number N that is a difference between the drive pulse number B and the drive pulse number A is obtained. Therefore, based on the drive speed table T1, the drive frequency corresponding to the drive pulse number N, that is, the descending speed, and the drive pulse number B that is the target height position are obtained by calculation.

Next, the presser foot motor 32 is driven based on the speed K and the drive pulse number B obtained in S18, and the presser foot member 24 is moved to the target height position at that speed K (S19). Next, when the detection voltage B is not a sewing start value, that is, a value belonging to the sewing area (S20: No), the detection voltage value B is written to the detection voltage A (S27), and a predetermined minute time has elapsed. (S28: Yes), the process returns to S13, and S13 and subsequent steps are repeatedly executed.

  When the detection voltage B is the sewing start value (S20: Yes), the presser foot motor 32 is further driven by a predetermined amount, and the presser foot 24 is pressed by the presser foot device 20 with a predetermined pressing force. The work cloth W placed thereon is pressed (S21). Then, a start command for driving the sewing machine motor 9 is output (S22). Next, when the sewing process is completed (S23: Yes), the presser foot member 24 is moved up to the set ascending position set on the operation panel 66 (S24), the process returns to S11, and the steps after S11 are repeatedly executed. The

  In S24, the presser member 24 is controlled to be raised at the end of sewing. However, the processing in S24 can be omitted. That is, it is also possible to keep the presser foot member 24 in the lowered position at the end of sewing. In this case, the work clamp member 24 may be configured to be moved to the raised position by separately performing a switch operation at the start of sewing.

  Here, the potentiometer 55 and the presser member raising / lowering control, particularly S11 to 13, etc. correspond to the operation amount detecting means, and the presser member raising / lowering control, particularly S18, S19, and the raised position setting control, especially S52, etc., are the motor control means. Correspondingly, the lift position setting control, particularly S52, corresponds to the drive amount changing means, the operation panel 66, the lift position setting control, etc., corresponds to the setting means, and the presser member raising / lowering control, particularly S20, S22, etc. is activated. Corresponds to means.

Next, the operation of the presser foot lifting control will be described.
As shown in FIG. 10, when the foot pedal 57 is in the neutral region and the cloth presser member 24 is located at the height rising position of 25.0 mm from the upper surface of the needle plate, the operator starts t2 from the time point t0. Step on to the middle of the operating area. In this case, the detection voltage of the potentiometer 55 changes from “1.5 V” to “3.12 V”. Therefore, the presser foot member 24 is positioned at the highest height position from the time t1 when the detection voltage of the potentiometer 55 reaches the start voltage “2.0V” of the operation region to the time t2 corresponding to “3.12V”. From “25.0 mm” to a height position “3.5 mm” in the middle of descending, the foot pedal descends at a high speed according to the depression speed of the foot pedal 57.

  At this time, although illustration is omitted, when the operator stops the stepping pedal 57 and raises (returns) the foot pedal 57 to the original height position before the foot pedal 57 is depressed, the presser foot member 24 moves to the foot pedal 57. Depending on the height position and the return speed, it rises at a stretch at high speed.

  Therefore, when the operator aligns the work cloth W to be used for sewing on the cloth receiving plate 16, and then depresses the foot pedal 57 again at the time t3 to step into the sewing area at once, the detected voltage is t2. Therefore, the cloth presser member 24 descends from the height position “3.5 mm” during the lowering and presses the work cloth W on the upper surface of the needle plate 12. At the same time, the start of sewing is instructed, and the sewing process is executed. By the way, when sewing is started, an optimum pressing force is applied to the presser member 24 on the presser member 24.

  However, when the sewing process is started, the operator can stop the stepping operation of the foot pedal 57. When the sewing process is completed, the presser foot member 24 automatically rises and returns to the preset raised position. Here, when the operation panel 66 is set so as to hold the presser foot member 24 in a lowered state with the end of the sewing process, the presser foot member 24 can be moved even when the sewing process is finished. It will not rise.

  In this way, the presser foot motor 57 detects the stepping amount of the foot pedal 57 with the potentiometer 55, and the presser foot motor 32 lowers the presser foot member 24 to a position corresponding to the detected effective stepping amount of the foot pedal 57. In addition to being controlled, the presser foot motor 32 is controlled so as to raise or lower the presser foot member 24 at a speed corresponding to the operation speed of the foot pedal 57. The presser foot member 24 can be moved to any desired height position, and the presser foot member 24 can be moved at a speed corresponding to the operation speed of the foot pedal 57. In addition, the workability of the sewing work can be improved.

  Further, since the sewing machine motor 9 is activated when the sewing area is detected based on the depression amount of the foot pedal 57, the cloth presser member 24 can be obtained simply by depressing the foot pedal 57 to the sewing area beyond the operating area. The sewing start can be commanded in conjunction with the presser foot movement by, and the operability of the sewing start operation can be greatly improved.

Next, a modified form of the embodiment will be described.
1] Instead of the presser foot motor 32 that drives the presser foot device 20, various electric motors such as a DC servo motor may be employed.

  2] The size of the neutral area, the operation area, and the sewing area allocated to the foot pedal 57 can be configured to be changeable according to the type and type of the sewing machine to be applied or by the operator.

  3) The speed at which the presser foot member 24 rises after the end of sewing may be stored at the lowering speed that has been lowered during the presser foot, and may be increased at the same speed as the lowering speed.

  4) The presser foot device 20 of the sewing machine of the present invention is not limited to the automatic pattern sewing machine, but may be applied to various industrial sewing machines and household sewing machines. Of course, it is not limited to 57, but may be a knee pad (knee pedal) operated by the knee of the operator.

  5] The present invention is not limited to the embodiment described above, and those skilled in the art can implement the present invention by adding various modifications without departing from the spirit of the present invention. The present invention includes such modifications.

It is a side view of the automatic pattern sewing machine which concerns on the Example of this invention. It is a perspective view from the back of an automatic pattern sewing machine. It is a side view of the internal structure of an automatic pattern sewing machine. It is a block diagram of a control system of an automatic pattern sewing machine. It is a front view of an operation panel. It is a graph which shows the setting data of a drive speed table. It is a graph which shows the setting data of a detection voltage pulse number table. It is a flowchart of cloth presser member elevation control. It is a flowchart of a raise position setting control. It is explanatory drawing which matched the detection voltage of the potentiometer, and the height position of the cloth pressing member.

Explanation of symbols

M Automatic pattern sewing machine 20 Work clamp device 24 Work clamp member 32 Work clamp member motor (stepping motor)
32E N encoder 57 Foot pedal W Work cloth

Claims (5)

In a sewing machine presser device having a presser foot motor that presses a work cloth, and a work press motor that moves the work presser closer to and away from the work cloth, and an operating body that commands start / stop of the sewing machine motor.
An operation amount detecting means for detecting an operation amount of the operating body;
The cloth presser motor is controlled to move the cloth presser member to a position corresponding to the operation amount of the operating body detected by the operation amount detecting means, and at a speed corresponding to the operation speed of the operating body. Motor control means for controlling the presser foot motor to move the presser foot member;
A presser device for a sewing machine, comprising:   The operation amount detection means is configured to be able to detect a neutral area on the operation start side, an operation area following the neutral area, and a sewing area following the operation area, and the motor control means can operate the operation body. The sewing machine presser device according to claim 1, wherein the presser motor is controlled to move the presser member after entering the operating region.   3. The sewing machine presser device according to claim 1, further comprising start control means for starting a sewing machine motor when the sewing area is detected by the operation amount detection means.   4. The sewing machine presser device according to claim 1, wherein the presser motor comprises a stepping motor, and the motor control means includes an encoder for detecting a rotation angle of the stepping motor.   Setting means for setting an arbitrary height position in the up-and-down movement trajectory of the work clamp member moved up and down as a lift position of the work clamp member is provided, and the motor control means includes the lift position and a descent in which the work clamp member presses the work cloth. 5. The sewing machine presser device according to claim 1, further comprising drive amount changing means for changing the drive amount of the presser foot motor in accordance with the distance from the position.

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