JP2023151077A - Needle thread holding mechanism and sewing device - Google Patents

Abstract

To provide a needle thread holding mechanism and a sewing device, which avoid a needle thread end from being caught in a stitch during sewing and make length of the needle thread end shorter than before.SOLUTION: A needle thread holding mechanism 80 has a stationary knife 97, a first holding member 81, a second holding member 82, and a holding moving part. The stationary knife 97 is fixed to a lower side of a needle plate 11 on which a needle hole 12 allowing insertion of a sewing needle is formed. The first holding member 81 is disposed on undersurface of a needle plate 11. The second holding member 82 is turnably supported by a support part 84 vertical to the needle plate 11 and holds a needle thread end of a needle thread by cooperating with the first holding member 81. The holding moving part has a motor and moves the second holding member 82 in a horizontal direction by power of the motor. The holding moving part moves the second holding member 82 to a standby position Q1, a holding position Q2, and a needle thread cutting position Q3. The needle thread cutting position Q3 is a position at which the needle thread end is cut by the stationary knife 97.SELECTED DRAWING: Figure 7

Description

The present invention relates to a needle thread holding mechanism and a sewing device.

A conventional sewing device includes a thread cutting mechanism and an upper thread clamping mechanism between a throat plate and a rotating hook. The thread cutting mechanism has a movable blade and a fixed blade. The thread cutting mechanism reciprocates the movable blade in the horizontal direction at the end of sewing, and cuts the needle thread extending through the work cloth from the eye of the sewing needle and the bobbin thread extending from the rotary hook. The needle thread clamping mechanism includes a first thread clamping member and a second thread clamping member. The needle thread clamping mechanism rotates the second thread clamping member to the clamping position when the first sewing needle moves above the needle plate after sewing starts, and works with the first thread clamping member to secure the thread end. sandwich the parts.

Japanese Patent Application Publication No. 2005-278928

In conventional sewing devices, a certain length of the needle thread end is required for the needle thread clamping mechanism to clamp the needle thread end, but on the other hand, when the needle thread end is released from clamping, There is a desire to shorten the length of the upper thread.

SUMMARY OF THE INVENTION An object of the present invention is to provide a needle thread holding mechanism and a sewing device that both avoid the needle thread end getting caught in the seam during sewing and shorten the length of the needle thread end compared to conventional methods. The goal is to provide the following.

The needle thread holding mechanism according to claim 1 of the present invention has a needle bar to which a sewing needle can be attached at the lower end, a needle bar mechanism that swings the needle bar in the vertical direction, and a needle hole through which the sewing needle is inserted. a fixed knife fixed to the lower side of the throat plate; a first holding member provided on the lower surface of the throat plate; a second holding member that cooperates to hold an upper thread end portion of the upper thread; and a holding and moving unit that includes a motor and moves the second holding member in a horizontal direction with the power of the motor; a standby position in which the needle hole is disposed between the first holding member and the second holding member in the direction; and a standby position in which the second holding member is spaced from the needle hole in the horizontal direction; a holding position where a second holding member overlaps the first holding member in the vertical direction; and a needle thread cutting position where the fixed knife cuts the needle thread end held by the first holding member and the second holding member. and the holding and moving section that moves the second holding member. In the needle thread holding mechanism according to the first aspect, by setting the second holding member to the holding position, the needle thread can be held by the first holding member and the second holding member. The needle thread holding mechanism can cut the needle thread by placing the second holding member in the needle thread cutting position. Therefore, the needle thread holding mechanism can both stably hold the needle thread in the holding position and make the length of the needle thread end shorter than before.

The support portion of the needle thread holding mechanism according to a second aspect of the present invention is provided on the motor side with respect to the needle hole in a direction from the motor to the needle hole in a plane parallel to the needle plate. The needle thread holding mechanism according to the second aspect of the present invention can increase the degree of freedom in designing the side opposite to the motor side with respect to the needle hole in the direction from the motor to the needle hole on a plane parallel to the needle plate.

The holding position of the needle thread holding mechanism according to a third aspect of the present invention is located between the standby position and the needle thread cutting position. In the needle thread holding mechanism according to the third aspect of the present invention, rotation control of the second holding member is easier than when the holding position is not located between the standby position and the needle thread cutting position.

The fixed knife of the needle thread holding mechanism according to claim 4 of the present invention is located above the first holding member, and the position where the needle thread is cut by the fixed knife is located at the first holding member. and the second holding member are upstream of the needle thread from a position where the needle thread is held. In the needle thread holding mechanism according to the fourth aspect, the length of the needle thread end can be made shorter than when the fixed knife is located below the first holding member.

When the second holding member of the needle thread holding mechanism of claim 5 of the present invention moves from the holding position to the needle thread cutting position, the first holding member and the second holding member continues to be maintained. The needle thread holding mechanism of claim 5 allows the needle thread end to be cut with the fixed knife more reliably than in the case where the needle thread end is cut without holding the needle thread end. The needle thread holding mechanism makes it easier to keep the cut shape of the needle thread end constant, compared to the case where the needle thread end is cut without holding the needle thread end.

A sewing device according to a sixth aspect of the present invention has a needle bar to which a sewing needle can be attached at a lower end thereof, a needle bar mechanism for vertically swinging the needle bar, and a needle hole through which the sewing needle is inserted. It comprises a throat plate and the needle thread holding mechanism according to any one of claims 1 to 5. In the sewing device according to the sixth aspect, by setting the second holding member of the needle thread holding mechanism to the holding position, the needle thread can be held by the first holding member and the second holding member. The sewing device can cut the needle thread by placing the second holding member in the needle thread cutting position. Therefore, the sewing device can stably hold the needle thread in the holding position and make the length of the needle thread end shorter than before.

The sewing device according to a seventh aspect of the present invention controls the motor to move the second holding member from the standby position to the holding position after the first needle drops and before the second needle drops. The apparatus further includes a control device that executes an upper thread holding control process and an upper thread cutting process for moving the second holding member from the holding position to the upper thread cutting position after the upper thread holding control process. The sewing device according to the seventh aspect is capable of automatically executing the upper thread holding control process and the upper thread cutting process.

The control device of the sewing apparatus according to claim 8 of the present invention performs the needle thread cutting process after the needle thread holding control process and before the needle drop of the second stitch. In the sewing device according to the eighth aspect of the present invention, the needle thread cutting process can be automatically executed after the needle thread holding control process and before the needle drop of the second stitch. The sewing device can cut the needle thread end at a relatively early stage after starting sewing.

The control device of the sewing device according to the ninth aspect of the present invention performs the needle thread cutting process after the needle thread retention control process and after the needle drop of the second stitch. The sewing device according to the present invention can automatically execute the needle thread cutting process after the needle thread holding control process and after the second needle drops. Compared to the case where the sewing device automatically performs the thread cutting process after the needle thread retention control process and before the second needle drop, the needle thread end cut in the thread cutting process falls off from the already formed stitch. Possibility can be reduced.

1 is an overall perspective view of a sewing device 1. FIG. FIG. 6 is a perspective view of the cutting mechanism 60 and the needle thread holding mechanism 80. FIG. 6 is an exploded perspective view of a portion of the cutting mechanism 60 and a portion of the needle thread holding mechanism 80. 7 is a bottom view of a portion of the cutting mechanism 60 and a portion of the needle thread holding mechanism 80. FIG. 6 is a bottom view of a portion of the cutting mechanism 60. FIG. 7 is a bottom view of a motor 59, a cam plate 70, and links 73 and 74 that are part of a link mechanism 72. FIG. 7 is a bottom view of a portion of the needle thread holding mechanism 80. FIG. 1 is a block diagram showing the electrical configuration of sewing device 1. FIG. 3 is a flowchart of main processing of the sewing device 1. FIG. (A) is a bottom view of a part of the motor 59, the cam plate 70, and the link mechanism 72 when the second holding member 82 is in the standby position Q1, and (B) is a bottom view of the second holding member 82 in the holding position. FIG. 7C is a bottom view of a part of the motor 59, cam plate 70, and link mechanism 72 when the second holding member 82 is at the upper thread cutting position Q3; FIG. 7 is a bottom view of a plate 70 and a portion of a link mechanism 72. FIG. (A) is a bottom view of a part of the cutting mechanism 60 and a part of the needle thread holding mechanism 80 when the second holding member 82 is in the standby position Q1, and (B) is a bottom view of a part of the cutting mechanism 60 and a part of the upper thread holding mechanism 80 when the second holding member 82 is in the standby position Q1. FIG. 7C is a bottom view of a part of the cutting mechanism 60 and a part of the upper thread holding mechanism 80 when the second holding member 82 is at the needle thread cutting position Q3; FIG. 60 and a bottom view of a portion of the upper thread holding mechanism 80. FIG. (A) is a sectional view taken along the G1-G1 line in FIG. 11(A), (B) is a sectional view taken along the G2-G2 line in FIG. 11(B), and (C) is a sectional view taken along the G2-G2 line in FIG. FIG. 11(C) is a sectional view taken along line G3-G3 in the direction of arrows. (A) is a sectional view taken along the F1-F1 line in FIG. 11(A), (B) is a sectional view taken along the F2-F2 line in FIG. 11(B), and (C) FIG. 11(C) is a sectional view taken along line F3-F3 in the direction of arrows. (A) is a bottom view of a portion of the motor 59, cam plate 70, and link mechanism 72 when the movable blade 62 is at the movable end position P4, and (B) is a bottom view when the movable blade 62 is at the cutting position P3. FIG. 7 is a bottom view of a part of the motor 59, the cam plate 70, and the link mechanism 72 at the time of FIG. (A) is a bottom view of a part of the cutting mechanism 60 and a part of the upper thread holding mechanism 80 when the movable blade 62 is at the movable end position P4, and (B) is a bottom view of a part of the cutting mechanism 60 and a part of the needle thread holding mechanism 80 when the movable blade 62 is at the movable end position P4. FIG. 7 is a bottom view of a portion of the cutting mechanism 60 and a portion of the needle thread holding mechanism 80 when the needle thread holding mechanism 80 is in the state shown in FIG.

Embodiments of the present invention will be described. In the following description, left and right, front and back, and up and down directions indicated by arrows in the drawings will be used. The left-right direction, the front-back direction, and the up-down direction of the sewing device 1 are the X-axis direction, the Y-axis direction, and the Z-axis direction, respectively.

The structure of the sewing device 1 will be explained with reference to FIG. The sewing device 1 can sew in a 360-degree direction by feeding the sewing object 19 in the X-axis direction and the Y-axis direction with respect to the sewing needle 15. The object to be sewn 19 is, for example, cloth, leather, or the like. The sewing device 1 includes a bed section 2, a pillar section 3, an arm section 4, a cloth feeding device 5, a control section 10 (see FIG. 8), and an operation panel 18. The bed section 2 is installed on a sewing machine desk 6. The bed section 2 includes a workbench 7 on the front side of the upper surface. The workbench 7 includes a needle plate 11 approximately in the center. A needle hole 12 is formed approximately in the center of the needle plate 11. The sewing device 1 includes a lower shaft (not shown) and a swinging vertical hook inside the bed portion 2. The swinging vertical hook is disposed below the throat plate 11, and its lower shaft extends in the front-rear direction. The front end of the lower shaft is connected to the swinging vertical hook. The swinging vertical hook accommodates a bobbin wound with bobbin thread, and swings back and forth around the lower shaft.

The pillar portion 3 extends upward from the rear portion of the bed portion 2. The arm portion 4 extends forward from the upper portion of the pillar portion 3 and rotatably supports the main shaft therein. The main shaft extends in the front-rear direction and is connected to a main motor 17 (see FIG. 8) provided on the rear side inside the arm portion 4. The continuous rod extends in the vertical direction inside the pillar portion 3. The main shaft is connected to the lower shaft via a connecting rod. Therefore, when the main motor 17 is driven, the main shaft rotates, and as the main shaft rotates, the swinging vertical hook is driven. The sewing machine desk 6 is provided with an operation panel 18 on the right side of the upper surface. The operation panel 18 is, for example, a touch panel, and includes a display section 13 and an input section 16. The display section 13 displays various information, and the input section 16 receives input of various information such as an instruction to start sewing.

The arm portion 4 includes a tip portion 8 at its front end. A lower end portion of the tip portion 8 faces the upper surface of the throat plate 11. The distal end portion 8 supports the needle bar 14 and the presser bar 20 so as to be movable up and down. The needle bar 14 extends in the vertical direction and projects downward from the tip 8. A sewing needle 15 is attached to the lower end of the needle bar 14. The sewing needle 15 has an eye hole, and holds the upper thread by passing the upper thread through the eye hole. The needle bar 14 is connected to the main shaft. When the needle bar 14 moves up and down due to the rotation of the main shaft, the sewing needle 15 moves up and down and passes through the needle hole 12. The sewing needle 15, which moves up and down, forms stitches on the workpiece 19 in cooperation with the swinging vertical hook. The presser bar 20 extends vertically to the left of the needle bar 14 and projects downward from the tip 8. The presser foot 9 is attached to the lower end of the presser bar 20. The presser foot 9 intermittently presses the workpiece 19 downward.

The cloth feeding device 5 includes an X motor 21 (see FIG. 8), a cloth holder 22, a support section 23, a shaft section 24, a Y motor 25 (see FIG. 8), and the like. The cloth feeding device 5 includes an X rail, an X moving plate, a Y rail, and a Y moving plate (not shown). The X motor 21 is provided inside the bed section 2 on the rear side. The X rail extends in the X-axis direction inside the bed section 2 and in front of the X motor 21. The X moving plate is connected to the X rail so as to be movable left and right, and also connected to the X motor 21. The X moving plate moves left and right along the X rail by the driving force of the X motor 21. The Y rail is fixed to the upper surface of the X moving plate and extends in the Y-axis direction. The Y rail moves left and right integrally with the X moving plate. The Y moving plate is connected to the Y rail so as to be movable back and forth. The cloth holder 22 is fixed to the upper surface of the Y moving plate. The cloth holder 22 moves left and right integrally with the X moving plate and the Y moving plate, and moves forward and backward integrally with the Y moving plate. Therefore, the cloth holder 22 can be moved in the horizontal direction. The support portion 23 is connected to the rear portion of the presser arm 32 of the cloth holder 22. The support portion 23 can move laterally together with the cloth holder 22. The shaft portion 24 extends rearward from the support portion 23 to the inside of the pillar portion 3, and can move back and forth. The front end of the shaft portion 24 is connected to the support portion 23 via a slider. The Y motor 25 is provided inside the pillar section 3 and connected to the shaft section 24 . When the shaft portion 24 moves back and forth by the driving force of the Y motor 25, the support portion 23, cloth holder 22, and Y moving plate move back and forth integrally.

The cloth holder 22 includes a feed plate 31, a presser arm 32, a pair of connecting parts 33, a presser frame 34, a pair of air cylinders 35 (only one is shown in FIG. 1), and the like. The feed plate 31 extends forward from the top surface of the Y moving plate, and is provided with a clamping frame 36 at the front end. The pinching frame 36 has a rectangular frame shape in plan view and can support the workpiece 19 . The presser arm 32 extends upward from the rear end of the feed plate 31, and further bends and extends forward. The presser arm 32 secures the rear end of the feed plate 31 by sandwiching it between it and the upper surface of the Y moving plate. The distal end portion 37 of the presser arm 32 has a substantially rectangular shape when viewed from the front. The pair of connecting portions 33 are arranged in the left-right direction at the distal end portion 37 and can be moved up and down. The pair of connecting portions 33 support the presser frame 34. The presser frame 34 has a substantially rectangular frame shape when viewed from above, and faces the clamping frame 36 in the vertical direction. A pair of air cylinders 35 are provided on the left and right sides of the presser arm 32. The pair of air cylinders 35 are connected to the pair of connecting portions 33, respectively. When the pair of air cylinders 35 are driven to move the pair of connecting portions 33 up and down, the presser frame 34 moves up and down between the clamping position and the separated position. The clamping position is a position where the workpiece 19 supported by the clamping frame 36 is pressed from above. The remote position is a position upwardly away from the object to be sewn 19. The sewing device 1 can sew in a 360 degree direction by moving the cloth holder 22 holding the workpiece 19 in the X-axis direction and the Y-axis direction with respect to the sewing needle 15.

As shown in FIG. 2, the sewing device 1 includes a cutting mechanism 60 and an upper thread holding mechanism 80 on the lower surface side of the throat plate 11. The cutting mechanism 60 is driven by the power of the motor 59, and performs an operation of cutting the upper thread and lower thread at the end of the sewing operation. The needle thread holding mechanism 80 is driven by the power of the motor 59 and releasably holds the needle thread end U (see FIG. 12) of the needle thread passed through the sewing needle 15 below the throat plate 11. The needle thread holding mechanism 80 bends and holds the needle thread that has passed below the workpiece 19 during the first stitch at the start of sewing. Therefore, the needle thread holding mechanism 80 prevents the thread from coming off from the sewing needle 15. The sewing device 1 has a motor 59 fixed to the back side of the bed section 2. The motor 59 is a pulse motor and is a driving source for the cutting mechanism 60 and the needle thread holding mechanism 80.

As shown in FIGS. 2 to 5, the cutting mechanism 60 includes a fixed blade 61, a movable blade 62, a biasing member 65, a support shaft 69, and a moving part 67. As shown in the figure, the fixed blade 61 is fixed to the lower side of the throat plate 11 in which the needle hole 12 through which the sewing needle 15 of the sewing device 1 is inserted is formed. The fixed blade 61 has a substantially L-shape in plan view and is fixed to the lower surface of the throat plate 11 with two screws 611. The fixed blade 61 includes a blade portion 612. The blade portion 612 is provided at the right rear portion of the fixed blade 61 and extends from the left side of the needle hole 12 toward the front of the needle hole 12.

The movable blade 62 is provided so as to be horizontally rotatable with respect to the fixed blade 61. The movable blade 62 includes a thread handling section 621, a blade section 622, a thread engaging section 623, a thread guiding section 624, a thread catching section 625, a thread clamping section 66, a thread releasing section 68, and the like. The thread handling portion 621 has a tip portion that is pointed toward the rear, and is a portion that enters into the upper thread ring formed by the upper thread. The blade portion 622 is an end portion of a through hole that vertically passes through the movable blade 62 and has a circular shape when viewed from the bottom. The thread engaging portion 623 is a portion of the upper thread ring that hooks the side extending from the sewing needle 15. The thread guide part 624 is a part that curves between the thread handling part 621 and the thread catching part 625 on the opposite side of the link 76 from the pin 763 with respect to the support shaft 69 . The thread guide section 624 guides the side of the upper thread ring that extends from the object to be sewn 19 to the thread catch section 625 . The thread catching section 625 is a part that catches the upper thread ring.

The thread clamping part 66 is a part of the lower surface of the movable blade 62 that can clamp the lower thread end D (see FIG. 13(A)) of the lower thread after being cut by the movable blade 62 between it and the biasing member 65. It is. The thread releasing portion 68 is a portion of the lower surface of the movable blade 62 in which the lower thread end D cannot be held between the biasing member 65 and the lower thread. The yarn releasing section 68 is provided at a portion of the lower surface of the movable blade 62 that is sandwiched between the yarn handling section 621 and the yarn catching section 625 and is in contact with the yarn catching section 625 and adjacent to the yarn holding section 66 . It is a concave portion that is concave toward the top. In other words, the thread holding section 66 is located below the thread release section 68.

The movable blade 62 has insertion portions 626 and 627 formed therein. The insertion part 626 is provided at the end of the movable blade 62 in the longitudinal direction opposite to the side where the thread handling part 621 is provided (the rear end of the movable blade 62 in the position shown in FIG. 3). It is a hole that penetrates through. The insertion portion 626 inserts a pin 763 of a link 76, which will be described later. The insertion portion 627 is a hole provided in the longitudinal center of the movable blade 62 and penetrating in the vertical direction. The support shaft 69 is inserted through the insertion portion 627, fixed to the lower surface of the throat plate 11, and supports the movable blade 62 so as to be able to reciprocate in a horizontal direction parallel to the throat plate 11. The support shaft 69, which is the center of rotation of the movable blade 62, is arranged so that the motor 59 is aligned with the needle hole 12 in the direction from the motor 59 on the plane parallel to the throat plate 11 toward the needle hole 12, in the front-rear direction in this embodiment. installed on the opposite side. The support shaft 69 is located to the right of the screw 611.

As shown in FIG. 4, the biasing member 65 is fixed to the lower side of the needle plate 11 in front of the needle hole 12 by two screws 651. The biasing member 65 is a bent leaf spring. The biasing member 65 includes a fixing part 652, a pressing part 653, and guide parts 654 and 655. The fixing part 652 has a plate shape extending from the front of the needle hole 12 to the right rear side and parallel to the needle plate 11, and is fixed to the needle plate 11 by two screws 651. The pressing portion 653 is a U-shaped portion when viewed from the bottom, which is bent downward from the left rear end of the fixing portion 652 and then bent backward. The pressing portion 653 is gently inclined toward the rear lower side. As shown in FIG. 13A, the guide portion 654 is a portion at the rear of the pressing portion 653 that slopes downward toward the rear. The guide portion 655 is a portion bent upward from the left end of the guide portion 654. The guide portions 654 and 655 guide the movable blade 62 to move so as to be disposed between the biasing member 65 and the throat plate 11. The biasing member 65 can bias the thread clamping portion 66 of the movable blade 62 upward.

As shown in FIG. 2, the moving unit 67 includes a motor 59, and uses the power of the motor 59 to rotate the movable blade 62 in the horizontal direction. The moving section 67 includes a motor 59, a cam plate 70, and a link mechanism 72. The motor 59 is a pulse motor, and is fixed to the lower back surface of the bed section 2 (see FIG. 1) with the output shaft 98 facing downward. The cam plate 70 converts the rotational force of the output shaft 98 of the motor 59 into power for driving the link mechanism 72. The link mechanism 72 drives the movable blade 62 of the cutting mechanism 60 according to the rotational direction and angle of the cam plate 70 to cut the upper thread and the lower thread. The link mechanism 72 drives the second holding member 82 of the needle thread holding mechanism 80 in accordance with the rotational direction and angle of the cam plate 70 to hold the needle thread end U at a predetermined time at the start of sewing.

As shown in FIG. 6, the cam plate 70 is disposed below the motor 59 and fixed to the tip of the output shaft 98 of the motor 59. The cam plate 70 is formed into a substantially semicircular shape when viewed from the bottom, and has a shaft hole 701 formed in the center. The tip of the output shaft 98 of the motor 59 is inserted and fixed into the shaft hole 701. The cam plate 70 rotates together with the output shaft 98. The cam plate 70 is provided with a grooved cam 71 within a range of about 180 degrees around the shaft hole 701. The grooved cam 71 has a semicircular arc shape in plan view, and is a groove shape in which the lower surface of the cam plate 70 is recessed in the thickness direction.

As shown in FIGS. 2 and 6, the link mechanism 72 includes links 73 to 76 and a roller member 77. The links 73 to 76 are arranged in order from the motor 59 side to the cutting mechanism 60 side. The link 73 has a substantially L-shaped plate shape when viewed from above, and is disposed below the cam plate 70. The link 73 rotatably fixes the roller member 77 above one end 731. The roller member 77 includes a rotating shaft extending in the vertical direction. The roller member 77 engages with the groove cam 71 of the cam plate 70. The link 73 has a shaft hole 734 in a central portion 733 bent at a substantially right angle between one end 731 and the other end 732 . Since the support shaft 735 is inserted into the shaft hole 734, the link 73 can rotate around the support shaft 735. The roller member 77 engages with the groove cam 71 of the cam plate 70. The other end 732 of the link 73 is rotatably connected to one end 741 of the link 74 via a pin 736.

The link 74 is rod-shaped and extends in the front-rear direction. The other end 742 of the link 74 is fixed to one end 751 of the link 75 with a screw 743. The link 75 is a C-shaped plate member that is open on the right side in front view. The other end 752 of the link 75 is located above the one end 751 and is fixed to the one end 761 of the link 76 with a screw 743. A center portion 753 of the link 75 that extends in the vertical direction inserts a support shaft 754 that extends in the vertical direction. The link 75 can rotate around the support shaft 754. The link 76 extends in the front-rear direction. As shown in FIGS. 3 and 4, the other end 762 of the link 76 bulges to the right in a substantially arc shape. The other end 762 of the link 76 has pins 763 and 764 that project upward. The pin 763 is provided at the front end of the link 76 and is inserted into the insertion portion 626 of the movable blade 62. The movable blade 62 is connected to the link 76 by a pin 763 of the link 76. The pin 764 is provided behind the pin 763, and is inserted into an insertion portion 861 of a second holding member 82 of the needle thread holding mechanism 80, which will be described later. The second holding member 82 is connected to the link 76 by a pin 764 of the link 76 . The link 76 is located below the second holding member 82 and the movable blade 62.

The moving part 67 can rotate the movable blade 62 in a horizontal direction parallel to the throat plate 11 about the support shaft 69 by moving the link 76 in the front-rear direction using the power of the motor 59. The moving unit 67 can move the movable blade 62 to a blade standby position P1, a release position P2, a cutting position P3, and a movable end position P4 shown in FIG. 5 in accordance with the drive of the motor 59. In FIG. 5, illustration of members other than the fixed blade 61, the movable blade 62, and the link 76 is omitted, and the position of the movable blade 62 is shown as the position of the blade portion 622.

In the blade standby position P1, the movable blade 62 is located away from the fixed blade 61, and the thread clamping portion 66 of the movable blade 62 is located between the throat plate 11 and the biasing member 65 and facing the biasing member 65. This is a position where the thread clamping section 66 can clamp the lower thread end D together with the biasing member 65. The release position P2 is a position where the thread release portion 68 of the movable blade 62 is disposed between the throat plate 11 and the biasing member 65 and facing the biasing member 65. The cutting position P3 is a position where the movable blade 62 crosses the fixed blade 61 and cuts the upper thread and the lower thread. The movable end position P4 is a position opposite to the blade standby position P1 with respect to the cutting position P3. That is, the movable end position P4 is located in a counterclockwise direction when viewed from the bottom around the support shaft 69 with respect to the cutting position P3, and the blade standby position P1 is located in a clockwise direction when viewed from the bottom around the support shaft 69 relative to the cutting position P3. It is in the direction of On the movement trajectory J1 of the movable blade 62, the cutting position P3 is between the blade standby position P1 and the movable end position P4, and the release position P2 is between the blade standby position P1 and the cutting position P3. The main process in which the sewing device 1 moves the movable blade 62 to each position will be described later.

As shown in FIGS. 2 to 4 and 7, the needle thread holding mechanism 80 includes a first holding member 81, a second holding member 82, and a moving section 67. The needle thread holding mechanism 80 of this embodiment further includes a fixed knife 97. The moving portion 67 is common to the needle thread holding mechanism 80 described above. The first holding member 81 is provided below the needle plate 11 in which the needle hole 12 through which the sewing needle 15 of the sewing device 1 is inserted is formed. The first holding member 81 is a plate-shaped member that extends in the horizontal direction parallel to the throat plate 11 and is long in the left-right direction. The first holding member 81 extends in the horizontal direction below the thread guide portion 624 of the movable blade 62 . The first holding member 81 is arranged to the left of the needle hole 12, and is fixed to the lower side of the needle plate 11 by a pair of front and rear screws 811. The right end portion of the first holding member 81 is inclined rearward toward the right side. As shown in FIG. 13(A), the first holding portion 86 of the second holding member 82 is arranged on the same horizontal plane as the movable blade 62. Here, the same horizontal plane means any virtual horizontal plane that passes through both the first holding part 86 and the movable blade 62, and includes the vertical extension range of the first holding part 86 and the movable blade 62. At least a portion thereof overlaps with the extension range in the vertical direction.

As shown in FIGS. 2 to 4 and 7, the second holding member 82 cooperates with the first holding member 81 to hold the needle thread end U of the needle thread. The second holding member 82 includes a first holding part 86 , a second holding part 87 , and a support part 84 . The first holding portion 86 is provided below the needle plate 11 and above the first holding member 81. The first holding part 86 is formed with an insertion part 88 which is plate-shaped and long in the front-rear direction and allows the sewing needle 15 to pass therethrough when the second holding member 82 is located at the standby position Q1 in FIG. The first holding portion 86 has insertion portions 861 and 863 and a pair of screw holes 862 formed therein. The insertion part 861 is a hole provided at the end of the first holding part 86 and penetrating in the vertical direction. The pin 764 of the link 76 is inserted into the insertion portion 861 . The insertion portion 863 is a hole provided in front of the insertion portion 861 and penetrating in the vertical direction. The second holding member 82 is rotatably supported in a horizontal direction parallel to the needle plate 11 by a support portion 84 inserted through the insertion portion 863 of the first holding portion 86 . The support portion 84 is a pin member provided perpendicularly to the throat plate 11. The second holding member 82 is rotatably supported in a horizontal direction parallel to the throat plate 11 by a support portion 84 inserted through the first holding portion 86 . The support portion 84 is located on the motor 59 side with respect to the needle hole 12 in the back of the needle hole 12, that is, in the direction from the motor 59 on a plane parallel to the throat plate 11 toward the needle hole 12, in the front-back direction in this embodiment. established in The distance between the center of the support shaft 69 and the center of the pin 764 is shorter than the distance E2 between the center of the support portion 84 and the center of the pin 764. Therefore, the amount of rotation of the movable blade 62 relative to the amount of movement of the link 76 is larger than the amount of rotation of the second holding member 82 relative to the amount of movement of the link 76.

The second holding part 87 has a plate shape that is long in the front-rear direction, and is provided below the first holding member 81. The length of the second holding part 87 in the front-back direction is shorter than the length of the first holding part 86 in the front-back direction. The second holding portion 87 is formed with an insertion portion 89 that allows the sewing needle 15 to pass therethrough when the second holding member 82 is located at the standby position Q1. The second holding portion 87 is formed with two holes 872 that penetrate in the left-right direction. The second holding part 87 is fixed to the lower surface of the first holding part 86 by a screw 871 inserted through a hole 872 while being overlapped with the first holding part 86 . At this time, the second holding part 87 is located in front of the supporting part 84. The insertion parts 88 and 89 of this embodiment are notches that open to the left, and the outlines of the insertion parts 88 and 89 in a plan view overlap each other. The insertion portions 88 and 89 are formed on the side of the second holding member 82 opposite to the insertion portion 861 with respect to the support portion 84 . The second holding part 87 is immovable with respect to the first holding part 86 and moves in the horizontal direction together with the first holding part 86. As shown in FIG. 12(A), the thickness of the first holding part 86 and the second holding part 87 is greater than the thickness of the first holding member 81. The thickness of the first holding part 86 is greater than the thickness of the second holding part 87.

As shown in FIG. 3, the fixed knife 97 is fixed to the lower side of the throat plate 11 in which the needle hole 12 through which the sewing needle 15 is inserted is formed. The fixed scalpel 97 includes a blade portion 96. The blade portion 96 is provided on the right side of the fixed blade 61 and placed on the left side of the needle hole 12. As shown in FIG. 12(A), the right end of the blade portion 96 is inclined toward the lower right. The fixed knife 97 is provided with a pair of front and rear holes 971 that penetrate in the vertical direction. The fixed knife 97 is located above the first holding member 81. The fixed knife 97 is fixed to the lower side of the throat plate 11 together with the first holding member 81 by screws 811 inserted through a pair of holes 971 .

The moving portion 67 is coupled to the second holding member 82 by inserting the pin 764 of the link 76 into the insertion portion 861 of the second holding member 82 . The moving part 67 can rotate the second holding member 82 in a horizontal direction parallel to the throat plate 11 around the support part 84 by moving the link 76 back and forth using the power of the motor 59 . That is, the moving part 67 can move each of the movable blade 62 and the second holding member 82. Specifically, the moving unit 67 moves the second holding member 82 at a standby position Q1, a holding position Q2, an upper thread cutting position Q3, a cutting position Q4, and a movable end position Q5, as shown in FIG. Moving. In FIG. 7, members other than the first holding part 86, the second holding part 87, the supporting part 84, the fixed knife 97, and the link 76 are not shown, and the position of the second holding member 82 is shown in the circle of the insertion part 89. The position of an imaginary circle inscribed in the right end portion of the arc is shown.

The standby position Q1 is a position where the needle hole 12 is arranged between the first holding member 81 and the second holding member 82 in the horizontal direction. The holding position Q2 is a position where the second holding member 82 is spaced apart from the needle hole 12 in the horizontal direction, and the second holding member 82 overlaps the first holding member 81 in the vertical direction. The needle thread cutting position Q3 is a position where the needle thread end U held by the first holding member 81 and the second holding member 82 is cut by the fixed knife 97. On the movement trajectory J2 of the second holding member 82, the holding position Q2 is located between the standby position Q1 and the needle thread cutting position Q3. The cutting position Q4 and the movable end position Q5 correspond to the cutting position P3 and the movable end position P4 of the movable blade 62, respectively. The main process in which the sewing device 1 moves the second holding member 82 to each position will be described later.

The electrical configuration of the sewing device 1 will be explained with reference to FIG. The control unit 10 of the sewing device 1 includes a CPU 41, a ROM 42, a RAM 43, a storage device 45, an I/O interface (hereinafter referred to as I/O) 46, drive circuits 51 to 56, and the like. CPU 41 controls the operation of sewing device 1 . The CPU 41 is connected to a ROM 42, a RAM 43, a storage device 45, and an I/O 46. The ROM 42 stores programs for executing various processes such as a main process (see FIG. 9) to be described later. The RAM 43 temporarily stores various information. The storage device 45 is nonvolatile and stores sewing information and the like. Sewing information is information including needle drop points.

The I/O 46 is connected to the drive circuits 51 to 56 and the input section 16. Drive circuit 51 is connected to main motor 17 . The drive circuit 52 is connected to the X motor 21. The drive circuit 53 is connected to the Y motor 25. Drive circuit 57 is connected to motor 59 . The X motor 21, Y motor 25, and motor 59 are pulse motors. The drive circuit 54 is connected to a pair of air cylinders 35. The drive circuit 55 is connected to the display section 13. The CPU 41 drives and controls the main motor 17, the X motor 21, the Y motor 25, and the pair of air cylinders 35 by controlling the drive circuits 51 to 54. The CPU 41 controls the display section 13 by controlling the drive circuit 56 . The input unit 16 detects information input by the worker and outputs the detection result to the CPU 41 via the I/O 46.

Encoders 91 to 93 are connected to main motor 17, X motor 21, and Y motor 25, respectively. Encoder 91 detects the rotational position of the output shaft of main motor 17. Encoder 92 detects the rotational position of the output shaft of X motor 21. Encoder 93 detects the rotational position of the output shaft of Y motor 25. Encoders 91 to 93 output detection results to CPU 41 via I/O 46.

With reference to FIGS. 9 to 15, the main processing executed in the sewing apparatuses 1 of specific examples 1 and 2 in which the upper thread cutting timings are different from each other will be described. In the main process, a process of forming stitches on the workpiece 19 according to the sewing pattern is executed. When the sewing device 1 is powered on, the CPU 41 starts main processing. When the sewing device 1 is powered on, the CPU 41 reads out a program for executing the main processing stored in the program storage area of the ROM 42 to the RAM 43. The CPU 41 executes the following steps according to instructions included in the program read into the RAM 43. Hereinafter, step will be abbreviated as S. Various parameters necessary to execute the main processing are stored in the storage device 45. Various data obtained in the course of main processing are stored in the RAM 43 as appropriate. The needle thread cutting timing need only be set before the execution of the main process, and may be set by the operator, or may be set automatically according to sewing conditions such as the type and thickness of the material to be sewn 19.

As shown in FIG. 9, the CPU 41 determines whether an origin detection instruction has been detected (S1). The operator operates the input unit 16 to input an origin detection instruction. When the origin detection instruction is not detected (S1: NO), the CPU 41 returns the process to S1. When detecting the origin detection instruction (S1: YES), the CPU 41 executes origin detection (S2) and then raises the presser foot 9 (S3).

The operator places the workpiece 19 to be sewn between the cloth holders 22 and operates the input section 16 to input an instruction to lower the presser foot 9. The CPU 41 determines whether an instruction to lower the presser foot 9 has been detected (S4). When the descending instruction is not detected (S4: NO), the CPU 41 returns the process to S4. When the lowering instruction is detected (S4: YES), the CPU 41 lowers the presser foot 9 (S5). As shown in FIG. 10(A), the roller member 77 provided at one end 731 of the link 73 of the moving part 67 is located at the left end of the grooved cam 71. As shown in FIG. 11A, the movable blade 62 of the cutting mechanism 60 is located at the blade standby position P1, and the second holding member 82 of the needle thread holding mechanism 80 is located at the standby position Q1. That is, when the second holding member 82 is in the standby position Q1, the movable blade 62 is in the blade standby position P1. In a bottom view, the first holding member 81 and the second holding member 82 partially overlap in the vertical direction. In a bottom view, the needle hole 12 is surrounded by a first holding member 81 and a second holding member 82. The blade portion 622 of the movable blade 62 is located near the boundary between the guide portion 654 and the pressing portion 653. As shown in FIG. 12(A), the second holding member 82 of the needle thread holding mechanism 80 is separated from the needle thread end U. The needle thread end U located below the needle hole 12 is surrounded by the first holding member 81 and the second holding member 82 . As shown in FIG. 13(A), the thread clamping portion 66 of the movable blade 62 of the cutting mechanism 60, together with the biasing member 65, clamps the lower thread end D in the vertical direction. The upper end of the pressing portion 653 of the biasing member 65 comes into contact with the thread clamping portion 66 of the movable blade 62 .

The CPU 41 determines whether a sewing instruction has been detected (S6). The operator operates the input unit 16 to input sewing instructions. When no sewing instruction is detected (S6: NO), the CPU 41 returns the process to S6. When the sewing instruction is detected (S6: YES), the CPU 41 drives the main motor 17 to start sewing the sewing pattern (S7). The CPU 41 determines whether it is time to hold the upper thread based on the detection result of the encoder 91 (S8). The needle thread retention timing of the sewing device 1 of this embodiment is set after the first stitch is sewn and before the second stitch is sewn. When it is not time to hold the upper thread (S8: NO), the CPU 41 returns the process to S8. When it is time to hold the upper thread (S8: YES), the CPU 41 executes upper thread holding control processing to move the second holding member 82 from the standby position Q1 to the holding position Q2 (S9).

The CPU 41 drives the motor 59 and rotates the output shaft 98 of the motor 59 clockwise when viewed from the bottom from the origin to the position shown in FIG. 10(B). As shown in FIG. 10(B), the roller member 77 moves to a position relatively rotated counterclockwise from the left end of the grooved cam 71 when viewed from the bottom. The link 73 rotates counterclockwise when viewed from the bottom about the support shaft 735, and moves the links 74 to 76. As shown in FIG. 11(B), the movable blade 62 of the cutting mechanism 60 moves to the rear of the blade standby position P1, and the second holding member 82 of the needle thread holding mechanism 80 moves from the standby position Q1 to the holding position Q2. The second holding member 82 is spaced apart from the needle hole 12 in the horizontal direction, and overlaps with the first holding member 81 in the vertical direction. As shown in FIG. 12(B), the needle thread holding mechanism 80 holds the needle thread end U in a bent state in an S-shape in side view between the first holding member 81 and the second holding member 82. As shown in FIG. 13(B), the thread clamping part 66 of the movable blade 62 of the cutting mechanism 60 maintains a state in which the lower thread end D is clamped in the vertical direction together with the biasing member 65.

The CPU 41 determines whether it is time to cut the needle thread based on the detection result of the encoder 91 (S10). The needle thread cutting timing of the sewing device 1 of this embodiment may be set after S9. In specific example 1, the upper thread cutting timing is set after the upper thread holding control process and before the needle drop of the second stitch. In specific example 2, the needle thread cutting timing is set at a predetermined timing after the needle thread holding control process and after the needle drop of the second stitch. The predetermined time in Example 2 may be set as appropriate, and in this example, it is after the third needle drop and before the fourth needle drop. When it is not time to cut the needle thread (S10: NO), the CPU 41 returns the process to S10. When it is time to hold the upper thread (S10: YES), the CPU 41 controls the motor 59 to execute upper thread cutting processing to move the second holding member 82 from the holding position Q2 to the upper thread cutting position Q3 after S9. (S12). The CPU 41 controls the motor 59 to move the movable blade 62 from the blade standby position P1 to the release position P2, and executes a release process to release the bobbin thread end D held in the process of S17 of the previous main process. (S12).

The CPU 41 drives the motor 59 and rotates the output shaft 98 of the motor 59 clockwise when viewed from the bottom from the position shown in FIG. 10(B) to the position shown in FIG. 10(C). As shown in FIG. 10(C), the roller member 77 moves to a position relatively rotated counterclockwise when viewed from the bottom from the position in FIG. 10(B). The link 73 rotates counterclockwise when viewed from the bottom about the support shaft 735, and moves the links 74 to 76. As shown in FIG. 11C, the movable blade 62 of the cutting mechanism 60 moves to the release position P2, and the second holding member 82 of the needle thread holding mechanism 80 moves from the holding position Q2 to the needle thread cutting position Q3. The second holding member 82 is spaced apart from the needle hole 12 in the horizontal direction, and a state is maintained in which the second holding member 82 and the first holding member 81 overlap in the vertical direction. The second holding member 82 vertically overlaps the blade portion 96 of the fixed knife 97. When the movable blade 62 of the cutting mechanism 60 is located in a range from the blade standby position P1 to the release position P2, the thread handling portion 621 of the movable blade 62 is located in front of the needle hole 12.

As shown in FIG. 12(C), the upper thread holding mechanism 80 maintains the upper thread end U bent in an S-shape in side view between the first holding member 81 and the second holding member 82. The first holding portion 86 of the second holding member 82 overlaps the fixed knife 97 in the vertical direction. Thereby, the needle thread end portion U is cut by the fixed knife 97. When the second holding member 82 moves from the holding position Q2 to the needle thread cutting position Q3, the first holding member 81 and the second holding member 82 continue to hold the needle thread end U. Therefore, the needle thread end U is cut by the fixed knife 97 while being held by the first holding member 81 and the second holding member 82. The position where the needle thread is cut by the fixed knife 97 is on the upstream side of the needle thread, that is, above the position where the first holding member 81 and the second holding member 82 hold the needle thread. As shown in FIG. 13(C), the thread releasing portion 68 of the movable blade 62 of the cutting mechanism 60 faces the pressing portion 653 of the biasing member 65 at a distance in the vertical direction. The thread clamping part 66 is moved to a retracted state from the pressing part 653 of the biasing member 65, and the state in which it clamps the bobbin thread end D in the vertical direction together with the biasing member 65 is released. As a result, the upper thread end U held by the upper thread holding mechanism 80 at the start of sewing is released after being cut near the needle hole 12, and the lower thread end D held by the cutting mechanism 60 is released.

The CPU 41 drives the motor 59, moves the movable blade 62 of the cutting mechanism 60 to the blade standby position P1, and moves the second holding member 82 of the needle thread holding mechanism 80 to the standby position Q1 (S13). The CPU 41 rotates the output shaft 98 of the motor 59 counterclockwise when viewed from the bottom from the position shown in FIG. 10(C) to the position shown in FIG. 10(A).

The CPU 41 determines whether the next needle dropping operation of the sewing needle 15 is the final needle of the sewing operation (S14). The CPU 41 counts the number of needle drops of the sewing pattern currently being sewn and stores it in the RAM 43. Therefore, by referring to the sewing information of the sewing pattern stored in the ROM 42, the CPU 41 can determine whether the next needle drop operation is the final needle or not. If it is not the last stitch (S14: NO), the CPU 41 returns to S14 and continues the sewing operation. When the last hand is reached (S14: YES), the CPU 41 stops the main motor 17 (S15).

The CPU 41 controls the motor 59 to move the movable blade 62 from the blade standby position P1 to the movable end position P4, and then to the cutting position P3 to execute a thread cutting process in which the upper thread and the lower thread are cut ( S16). The CPU 41 drives the motor 59, rotates the output shaft 98 of the motor 59 from the position shown in FIG. 10(A) to the position shown in FIG. 14(A) clockwise when viewed from the bottom, and moves the movable blade 62 from the blade standby position P1. Move to movable end position P4. As shown in FIG. 14(A), the roller member 77 moves to the right end of the grooved cam 71 (the end opposite to the left end of the grooved cam 71 in FIG. 10(A)). The link 73 rotates counterclockwise when viewed from the bottom about the support shaft 735, and moves the links 74 to 76. As shown in FIG. 15(A), the movable blade 62 of the cutting mechanism 60 moves to the movable end position P4. The blade portion 622 of the movable blade 62 is located behind the support shaft 69 and behind the needle hole 12. Both the thread clamping part 66 and the thread releasing part 68 of the movable blade 62 are arranged at positions retracted from the biasing member 65. A part of the movable blade 62 passes above the first holding member 81 in the process of moving from the blade standby position P1 to the movable end position P4. The second holding member 82 of the needle thread holding mechanism 80 moves to the movable end position Q5. The second holding member 82 is spaced apart from the needle hole 12 in the horizontal direction, and the second holding member 82 does not overlap with either the first holding member 81 or the fixed knife 97 in the vertical direction. The thread handling portion 621 of the movable blade 62 of the cutting mechanism 60 is located behind the spindle 69 and behind the needle hole 12. The thread handling portion 621 of the movable blade 62 of the cutting mechanism 60 is located in front of the pin 764 and does not interfere with the second holding member 82 .

The CPU 41 drives the motor 59, rotates the output shaft 98 of the motor 59 from the position shown in FIG. 14(A) to the position shown in FIG. 14(B) counterclockwise when viewed from the bottom, and moves the movable blade 62 to the movable end position P4. to the cutting position P3. As shown in FIG. 14(B), the roller member 77 moves from the right end of the grooved cam 71 to a position relatively clockwise when viewed from the bottom. The link 73 rotates clockwise when viewed from the bottom about the support shaft 735 from the position shown in FIG. 14(A), thereby moving the links 74 to 76. As shown in FIG. 15(B), the movable blade 62 of the cutting mechanism 60 moves to the cutting position P3. The blade portion 622 of the movable blade 62 is located at a position that vertically overlaps the needle hole 12. The front parts of the thread clamping part 66 and the thread releasing part 68 of the movable blade 62 are arranged at a position retracted from the biasing member 65. The second holding member 82 of the needle thread holding mechanism 80 moves to the cutting position Q4. The second holding member 82 is spaced apart from the needle hole 12 in the horizontal direction, and the second holding member 82 does not overlap with either the first holding member 81 or the fixed knife 97 in the vertical direction. When the movable blade 62 of the cutting mechanism 60 is located in a range from the movable end position P4 to the cutting position P3, the thread handling portion 621 of the movable blade 62 is located behind the needle hole 12.

The CPU 41 controls the motor 59 to move the movable blade 62 from the cutting position P3 to the blade standby position P1, and causes the biasing member 65 and the thread clamping part 66 to move the lower thread end D cut in the thread cutting process. A pinching process for pinching is executed (S17). The CPU 41 drives the motor 59, rotates the output shaft 98 of the motor 59 from the position shown in FIG. 14(B) to the position shown in FIG. 10(A) counterclockwise when viewed from the bottom, and moves the movable blade 62 from the cutting position P3. Move it to the blade standby position P1. The link 73 rotates clockwise when viewed from the bottom about the support shaft 735 from the position shown in FIG. 14(B), thereby moving the links 74 to 76. In the process of moving from the cutting position P3 to the blade standby position P1, the movable blade 62 moves the guide portions 654, 655 of the biasing member 65 while placing the bobbin thread end D cut in S16 on the thread clamping portion 66. , the thread holding portion 66 is disposed between the biasing member 65 and the throat plate 11. As a result, when the movable blade 62 is moved from the cutting position P3 to the blade standby position P1 as shown in FIG. It is held between the pressing portion 653 and the pressing portion 653 . The lower thread end D is held between the thread holding part 66 of the movable blade 62 and the pressing part 653 of the biasing member 65 until S12 of the next main process is executed. The CPU 41 then ends the main processing.

In the embodiment described above, the sewing device 1, throat plate 11, needle hole 12, needle bar 14, sewing needle 15, needle bar mechanism 30, and CPU 41 are the sewing device, throat plate, needle hole, needle bar, and sewing needle of the present invention, respectively. , a needle bar mechanism, and a control device. The needle thread holding mechanism 80, the first holding member 81, the second holding member 82, the support part 84, the moving part 67, the motor 59, and the fixed knife 97 are the needle thread holding mechanism, the first holding member, and the second holding member of the present invention, respectively. This is an example of two holding members, a support part, a holding moving part, a motor, and a fixed knife. The standby position Q1, the holding position Q2, the upper thread cutting position Q3, and the upper thread end U are examples of the waiting position, the holding position, the upper thread cutting position, and the upper thread end of the present invention, respectively. The processing in S16 and S17 is an example of thread cutting processing. The process in S17 is an example of a clamping process. The process in S12 is an example of release process. The process of S9 is an example of the needle thread retention control process of the present invention. The process of S12 is an example of the needle thread cutting process of the present invention.

The sewing device 1 of the above embodiment includes a needle bar mechanism 30, a throat plate 11, and an upper thread holding mechanism 80. The needle bar mechanism 30 has a needle bar 14 to which a sewing needle 15 can be attached at its lower end, and swings the needle bar 14 in the vertical direction. A needle hole 12 is formed through which a sewing needle 15 is inserted. The needle thread holding mechanism 80 includes a fixed knife 97, a first holding member 81, a second holding member 82, and a moving section 67. The fixed knife 97 is fixed to the lower side of the throat plate 11 in which the needle hole 12 through which the sewing needle 15 is inserted is formed. The first holding member 81 is provided on the lower surface of the needle plate 11. The second holding member 82 is rotatably supported by a vertical support portion 84 on the throat plate 11, and cooperates with the first holding member 81 to hold the needle thread end U of the needle thread. The moving unit 67 includes a motor 59 and uses the power of the motor 59 to move the second holding member 82 in the horizontal direction. The moving unit 67 moves the second holding member 82 to a standby position Q1, a holding position Q2, and an upper thread cutting position Q3. In the standby position Q1, the second holding member 82 is separated from the needle hole 12 and the first holding member 81 in the horizontal direction, and the needle hole 12 is located between the first holding member 81 and the second holding member 82. This is the position where it will be placed. The holding position Q2 is a position where the second holding member 82 is spaced apart from the needle hole 12 in the horizontal direction, and the second holding member 82 overlaps the first holding member 81 in the vertical direction. The needle thread cutting position Q3 is a position where the needle thread end U held by the first holding member 81 and the second holding member 82 is cut by the fixed knife 97. Therefore, the needle thread holding mechanism 80 can hold the needle thread with the first holding member 81 and the second holding member 82 by setting the second holding member 82 to the holding position Q2. The needle thread holding mechanism 80 can cut the needle thread by setting the second holding member 82 to the needle thread cutting position Q3. Therefore, the needle thread holding mechanism 80 can both stably hold the needle thread at the holding position Q2 and make the length of the needle thread end portion U shorter than before.

The support portion 84 is provided on the motor 59 side with respect to the needle hole 12 in the direction from the motor 59 on a plane parallel to the throat plate 11 toward the needle hole 12 . The needle thread holding mechanism 80 can increase the degree of freedom in designing the side opposite to the motor 59 side with respect to the needle hole 12.

The holding position Q2 is located between the standby position Q1 and the needle thread cutting position Q3. Therefore, in the upper thread holding mechanism 80, rotation control of the second holding member 82 is easier than when the holding position Q2 is not located between the standby position Q1 and the upper thread cutting position Q3.

The fixed knife 97 is located above the first holding member 81. The position where the fixed knife 97 cuts the upper thread is upstream of the upper thread than the position where the first holding member 81 and the second holding member 82 hold the upper thread. Therefore, the needle thread holding mechanism 80 can shorten the length of the needle thread end U compared to the case where the fixed knife 97 is located below the first holding member 81.

When the second holding member 82 moves from the holding position Q2 to the needle thread cutting position Q3, the first holding member 81 and the second holding member 82 continue to hold the needle thread end U. Therefore, the needle thread holding mechanism 80 can cut the needle thread end U more reliably with the fixed knife 97 than when cutting the needle thread end U without holding the needle thread end U. The needle thread holding mechanism 80 can easily keep the cut shape of the needle thread end U constant compared to the case where the needle thread end U is cut without holding the needle thread end U.

The CPU 41 controls the motor 59 to perform upper thread holding control processing (see FIG. 9 Step S9) is executed. The CPU 41 controls the motor 59 to execute the needle thread cutting process (S12 in FIG. 9) of moving the second holding member 82 from the holding position Q2 to the needle thread cutting position Q3 after S9. The sewing device 1 can automatically execute the upper thread holding control process and the upper thread cutting process.

The CPU 41 performs the needle thread cutting process in S12 after the needle thread holding control process and before the needle drop of the second stitch. The sewing device 1 can automatically execute the needle thread cutting process after the needle thread retention control process and before the needle drop of the second stitch. The sewing device 1 can cut the needle thread end U at a relatively early stage after starting sewing.

The CPU 41 performs the needle thread cutting process after the needle thread retention control process and after the second needle drop. The sewing device 1 can automatically execute the needle thread cutting process after the needle thread holding control process and after the second needle drops. Compared to the case where the sewing device 1 automatically performs the thread cutting process after the needle thread holding control process and before the needle drop of the second stitch, the sewing device 1 cuts the needle thread end U cut in the thread cutting process at the already formed stitch. It can reduce the possibility of falling out.

The cutting mechanism and sewing device of the present invention can be modified in various ways other than the above embodiments. The configurations of the sewing device 1 and the cutting mechanism 60 may be changed as appropriate. For example, the sewing device 1 may not include at least one of the cloth feeding device 5, the cutting mechanism 60, and the display section 13. The cutting mechanism 60 may be operated by the power of a motor other than the motor 59 of the upper thread holding mechanism 80, or the movable blade 62 may be operated by the power of the motor 59 via a power transmission member different from the link mechanism 72. may be moved. The correspondence relationship between the position of the movable blade 62 of the cutting mechanism 60 and the position of the second holding member 82 of the needle thread holding mechanism 80 may be changed as appropriate. The biasing member 65 may be omitted or may have a configuration other than a plate spring such as a coil spring. The support shaft 69 may be fixed on the motor 59 side with respect to the needle hole 12, that is, on the rear side.

The configuration of the needle thread holding mechanism 80 may be changed as appropriate. The configuration, shape, size, arrangement, etc. of the first holding member 81 and the second holding member 82 may be changed as appropriate. The first holding part 86 and the second holding part 87 may be an integral member, or the second holding member 82 does not include the second holding part 87, and the first holding member 81 and the second holding member 82 The needle thread end U may be held in any direction such as the vertical direction. The insertion parts 88 and 89 may be omitted, and the planar shape of the insertion parts 88 and 89 may be, for example, holes of any shape that penetrate in the vertical direction. The insertion portions 88 and 89 may have the same shape or different shapes. The first holding member 81 may be formed with an insertion portion such as a notch or a through hole that allows the sewing needle 15 to pass therethrough. The first holding part 86 does not need to be provided on the same horizontal plane as the movable blade 62. The position of the second holding member 82 may be changed as appropriate between the standby position Q1 and the holding position Q2. When the second holding member 82 is in the standby position Q1, the second holding member 82 may be separated from the needle hole 12 and the first holding member 81 in the horizontal direction. The support portion 84 only needs to be able to rotatably support the second holding member 82, and may be a cylindrical member. The support portion 84 may be fixed to the needle hole 12 on the side opposite to the motor 59 side, that is, on the front side.

The fixed knife 97 may be fixed at the same vertical position as the first holding member 81, or may be fixed below the first holding member 81. The position where the needle thread is cut by the fixed knife 97 may be a position where the first holding member 81 and the second holding member 82 hold the needle thread, or a position downstream of the needle thread from the position. When the second holding member 82 moves from the holding position Q2 to the needle thread cutting position Q3, the first holding member 81 and the second holding member 82 may release the needle thread end U.

The program including instructions for the sewing device 1 to perform main processing may be stored in the storage device 45 before the CPU 41 executes the program. Therefore, the program acquisition method, acquisition route, and device that stores the program may be changed as appropriate. The program executed by the CPU 41 may be received from another device via a cable or wireless communication, and may be stored in a nonvolatile storage device. Other devices include, for example, a PC and a server connected via a network.

Part or all of the processing performed by the sewing device 1 may be performed by an electronic device (for example, an ASIC) other than the CPU 41. The processing performed by the sewing device 1 may be distributed by a plurality of electronic devices (for example, a plurality of CPUs). The order of each step of the process performed by the sewing device 1 can be changed, steps can be omitted, or added as necessary. The scope of the present invention also includes a mode in which an operating system (OS) or the like running on the sewing device 1 performs part or all of each process based on instructions from the CPU 41.

The timing at which the upper thread holding mechanism 80 releases the lower thread end D and the timing at which the upper thread end U is cut may be the same or different. If the sewing device 1 does not include the cutting mechanism 60, the sewing device 1 may omit the processes of S16 and S17. The CPU 41 does not have to rotate the second holding member 82 in the processes of S16 and S17. The upper thread retention control process may be executed before starting the first stitch. The CPU 41 does not need to move the movable blade 62 when executing at least one of S9 and S12.

The fixed knife 97 is positioned below the first holding member 81, and when the second holding member 82 moves from the holding position Q2 to the upper thread cutting position Q3, the second holding part 87 of the second holding member 82 and The needle thread may be cut by vertically overlapping the fixed knife 97. In this case, the position where the needle thread is cut by the fixed knife 97 is on the downstream side of the needle thread, that is, below the position where the first holding member 81 and the second holding member 82 hold the needle thread. . Furthermore, even if the needle thread is cut, it is held by the first holding member 81 and the second holding member 82 upstream of the cutting part, so even if the needle thread cutting process is executed before the third needle drops, There is no possibility that the upper thread will come out of the needle hole 12.

The above modifications may be combined as appropriate to the extent that there is no contradiction. The technology disclosed in this specification can be realized in various forms, such as a method for controlling a sewing device, a computer program for realizing the above method, and a recording medium on which the computer program is recorded. This can be realized in the form of

1: Sewing device 11: Throat plate 12: Needle hole 14: Needle bar 15: Sewing needle 30: Needle bar mechanism 41: CPU
59 : Motor 67 : Moving part 80 : Needle thread holding mechanism 81 : First holding member 82 : Second holding member 97 : Fixed knife Q1 : Standby position Q2 : Holding position Q3 : Needle thread cutting position U : Needle thread end

Claims (9)

a needle bar mechanism having a needle bar to which a sewing needle can be attached at the lower end and swinging the needle bar in the vertical direction;
a fixed knife fixed to the lower side of a throat plate in which a needle hole through which the sewing needle is inserted;
a first holding member provided on the lower surface of the throat plate;
a second holding member rotatably supported on the throat plate by a support portion and holding the needle thread end of the needle thread in cooperation with the first holding member;
A holding and moving unit having a motor and moving the second holding member in a horizontal direction using power of the motor,
a standby position in which the needle hole is arranged between the first holding member and the second holding member in the horizontal direction;
a holding position where the second holding member is spaced apart from the needle hole in the horizontal direction, and where the second holding member overlaps the first holding member in the vertical direction;
and a needle thread cutting position where the fixed knife cuts the needle thread end held by the first holding member and the second holding member, and the holding and moving unit which moves the second holding member. Features an upper thread retention mechanism. The upper thread according to claim 1, wherein the support portion is provided on the motor side with respect to the needle hole in a direction from the motor to the needle hole on a plane parallel to the needle plate. Retention mechanism. The needle thread holding mechanism according to claim 1, wherein the holding position is located between the standby position and the needle thread cutting position. The fixed knife is located above the first holding member,
The position where the needle thread is cut by the fixed knife is on the upstream side of the needle thread from the position where the first holding member and the second holding member hold the needle thread. The needle thread holding mechanism according to any one of claims 1 to 3. When the second holding member moves from the holding position to the upper thread cutting position, the first holding member and the second holding member continue to hold the upper thread end. The needle thread holding mechanism according to any one of claims 1 to 4. a needle bar mechanism having a needle bar to which a sewing needle can be attached at the lower end and swinging the needle bar in the vertical direction;
a needle plate formed with a needle hole through which the sewing needle is inserted;
A sewing device comprising the needle thread holding mechanism according to any one of claims 1 to 5. controlling the motor;
Upper thread holding control processing of moving the second holding member from the standby position to the holding position after the first needle drops and before the second needle drops;
Sewing according to claim 6, further comprising a control device that executes a needle thread cutting process of moving the second holding member from the holding position to the needle thread cutting position after the needle thread holding control process. Device. 8. The sewing device according to claim 7, wherein the control device performs the needle thread cutting process after the needle thread holding control process and before the needle drop of the second stitch. The sewing device according to claim 7, wherein the control device performs the needle thread cutting process after the needle thread holding control process and after the needle drop of the second stitch.

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