Bird nest preventing device for sewing machine

Abstract

The utility model discloses a bird nest prevention device for a sewing machine, which comprises a sewing machine shell, a thread hooking mechanism for hooking and clamping threads, a thread cutting mechanism for cutting off upper threads and a thread control mechanism for controlling the tension of the upper threads, the thread control mechanism comprises a third fixing base fixed to the upper end of the sewing machine shell, the third fixing base is provided with a second rotating shaft capable of rotating, the second rotating shaft is connected with a thread control rod, and the thread control rod is provided with a thread take-up part used for allowing the upper thread to penetrate through; the third fixing seat is provided with a fourth air cylinder used for driving the wire control rod to swing around the center line of the second rotating shaft.

Description

Technical Field

[0001] This utility model belongs to the field of sewing machine technology, specifically a bird nest prevention device for sewing machines. Background Technology

[0002] Patent No. 202320309307.4 discloses an anti-bird nest device for a sewing machine, including a fixed seat installed on the left side of the sewing machine head. The fixed seat is equipped with a thread cutting mechanism for cutting the thread and a thread hooking mechanism for hooking and clamping the thread. The thread cutting mechanism includes a mounting plate fixedly connected to the fixed seat. The mounting plate is equipped with a mounting block that can slide at an angle. The mounting block is connected to a first shaft. A second connecting plate is fixedly installed on the mounting block. The end of the second connecting plate is connected to a cutter mounting seat through a tension spring. A limiting block is provided on the mounting block to restrict the rotation of the cutter mounting seat.

[0003] The patent disclosure has certain flaws. After the cutter mounting part of the cutter mounting base contacts the presser foot, the cutter mounting part moves to the right along the presser foot. The top thread can only be cut by the cutter when it enters through the slit. When sewing different patterns of fabric, the cutter cannot cut the top thread that has not entered the slit, and the anti-bird's nest function fails. Summary of the Invention

[0004] This utility model addresses the aforementioned technical problems by providing an anti-bird nest device for sewing machines. The improved device structure ensures that bird nest shapes are avoided when sewing different patterns of fabric, thereby improving sewing quality.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: a bird nest prevention device for sewing machines, including a sewing machine housing, a hook mechanism for hooking and clamping the thread, a cutting mechanism for cutting the top thread, and a thread control mechanism for controlling the tension of the top thread. The thread control mechanism includes a third fixed seat fixed to the upper end of the sewing machine housing, a second rotating shaft that can rotate, a thread control rod connected to the second rotating shaft, and a thread take-up part for threading the top thread. The third fixed seat is equipped with a fourth cylinder for driving the thread control rod to swing around the center line of the second rotating shaft.

[0006] To optimize the above technical solution, the present invention also includes the following improved technical solutions.

[0007] An extension seat is installed on the right end of the third fixed seat, and the second rotating shaft is rotatably mounted on the extension seat; a spring for resetting is sleeved on the drive shaft of the fourth cylinder; the drive shaft of the fourth cylinder is connected to a first connecting member, the first connecting member is rotatably connected to a second connecting member, and the second connecting member drives the second rotating shaft to rotate through the third connecting member.

[0008] The aforementioned thread-cutting mechanism includes a second fixed seat fixed to the front side of the sewing machine housing. A second mounting plate that can be raised and lowered is provided on the front side of the second fixed seat. A third mounting plate that can move obliquely is installed on the front side of the second mounting plate. The third mounting plate is connected to the first mounting block through a tension spring. The third mounting plate is rotatably mounted with the first mounting block through a first rotating shaft. A second mounting block is installed at the lower end of the first mounting block. A thread-cutting handle is fixed between the first mounting block and the second mounting block. A cutter is provided at the end of the thread-cutting handle.

[0009] The above-mentioned hook mechanism includes a first fixed seat fixed to the sewing machine housing, a first mounting plate provided at the front end of the first fixed seat, a hook obliquely provided on the front side of the first mounting plate, a hooking part provided at the front end of the hook, an inclined connecting rod part provided at the lower end of the first mounting plate, and a connecting seat for guiding the movement of the hook fixed at the end of the connecting rod part.

[0010] The lower end of the first mounting block has an upper recess, and the upper end of the second mounting block has a lower recess, forming a space between the upper and lower recesses for mounting the tangent shank.

[0011] The second fixed base is vertically mounted with a second cylinder. The drive rod of the second cylinder is mounted with a second connecting plate. A third connecting plate is mounted at the front end of the second connecting plate and is connected to the second mounting plate. A third cylinder is obliquely downward on the front side of the second mounting plate. The drive rod of the third cylinder is fixedly connected to the third mounting plate. A first mounting base is mounted at the front end of the second fixed base. A first connecting block is slidably mounted at the front end of the first mounting base via a first guide rail. The top of the first connecting block is fixedly connected to the second connecting plate.

[0012] The second connecting plate is provided with a second adjustment groove and a third adjustment groove in parallel. The second adjustment groove and the third adjustment groove are arranged in parallel. A second screw passes through the second adjustment groove and is connected to the third connecting plate. A third screw passes through the third adjustment groove and is connected to the third connecting plate.

[0013] The third mounting plate is provided with a fourth adjustment groove, and a fourth screw is installed in the fourth adjustment groove; the first mounting block is equipped with a fifth screw; one end of the tension spring is connected to the fourth screw, and the other end of the tension spring is connected to the fifth screw.

[0014] The aforementioned connecting seat has a hook mounting part and a suction mounting part. The hook is slidably mounted between the lower surface of the connecting rod part and the upper surface of the hook mounting part. A pressure plate is installed at the end of the connecting rod part, and the lower surface of the pressure plate cooperates with the hook part to clamp the face line. The suction mounting part has a through hole, and a suction pipe is installed in the through hole.

[0015] The front side of the first fixed base is connected to the first mounting plate via a first connecting plate. The first connecting plate has a first adjustment groove, and a first screw passes through the first mounting plate and is fixed in the first adjustment groove.

[0016] Compared with the prior art, the present invention provides an anti-bird nest device for sewing machines, which uses a hook mechanism to hook the top thread of the needle and fix the next section of thread, a thread cutting mechanism to cut the top thread between the hook and the needle, and an independently controlled thread control mechanism to tighten or loosen the top thread, thereby improving the anti-bird nest effect and increasing the applicability of the device. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of this embodiment.

[0018] Figure 2 This is a three-dimensional structural diagram of the hook-line mechanism.

[0019] Figure 3 This is an exploded view of the hook-and-line mechanism.

[0020] Figure 4 This is a three-dimensional structural diagram of a tangent mechanism.

[0021] Figure 5 This is an exploded view of a tangential mechanism.

[0022] Figure 6 This is a three-dimensional structural diagram of the control line mechanism. Detailed Implementation

[0023] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0024] Figures 1 to 6 The diagram shown is a structural schematic of this utility model.

[0025] The reference numerals in the attached drawings are as follows: sewing machine housing 1, first fixed base 2, first connecting plate 3, first adjusting groove 3a, first mounting plate 4, connecting rod part 4a, first cylinder 5, first cylinder mounting bracket 6, thread hook 7, thread hook part 7a, thread hook connecting block 8, connecting base 9, thread hook mounting part 9a, suction mounting part 9b, through hole 9c, pressure plate 10, suction pipe 11, second fixed base 12, second cylinder 13, second connecting plate 14, second adjusting groove 14a, third adjusting groove 14b, third connecting plate 15, second mounting plate 16, first mounting base 17, first connecting... Block 18, First guide rail 19, Third mounting plate 20, Fourth adjustment groove 20a, Second guide rail 21, Third cylinder 22, Third cylinder mounting bracket 23, Cutting handle 24, First rotating shaft 25, First mounting block 26, Upper recess 26a, Second mounting block 27, Lower recess 27a, Cutting blade 28, Fourth screw 29, Fifth screw 30, Tension spring 31, Third fixing seat 32, Extension seat 33, Control rod 34, Thread take-up part 34a, Fourth cylinder 35, Spring 36, First connector 37, Second connector 38, Third connector 39, Second rotating shaft 40.

[0026] like Figure 1 As shown, the present invention provides a bird nest prevention device for sewing machines, including a sewing machine housing 1. The sewing machine housing 1 is equipped with a hook mechanism for hooking and clamping the thread, a thread cutting mechanism for cutting the thread, and a thread control mechanism for tightening and loosening the thread.

[0027] like Figure 2 and Figure 3 As shown, the hook mechanism includes a first fixed base 2 fixed to the sewing machine housing 1, a first connecting plate 3 on the front side of the first fixed base 2, and a first mounting plate 4 on the front side of the first connecting plate 3. The first connecting plate 3 has a first adjusting groove 3a, and a first screw passes through the first mounting plate 4 and is fixed in the first adjusting groove 3a. By adjusting the position of the first screw in the first adjusting groove 3a, the tilt of the first mounting plate 4 can be adjusted.

[0028] A first cylinder 5 is provided on the front side of the first mounting plate 4. The cylinder body of the first cylinder 5 is obliquely mounted on the front side of the first mounting plate 4 through the first cylinder mounting bracket 6. The drive rod of the first cylinder 5 is provided with a hook 7. The hook 7 is fixedly connected to the drive rod of the first cylinder 5 through a hook connecting block 8. The front end of the hook 7 is provided with a hooking part 7a, which hooks the surface line.

[0029] The lower end of the first mounting plate 4 has an inclined connecting rod portion 4a. A connecting seat 9, which guides the movement of the hook 7, is fixedly mounted at the end of the connecting rod portion 4a. The connecting seat 9 has a hook mounting portion 9a and a suction mounting portion 9b. The hook 7 is slidably mounted between the lower surface of the connecting rod portion 4a and the upper surface of the hook mounting portion 9a. A pressure plate 10 is mounted at the end of the connecting rod portion 4a, and the hook portion 7a engages with the lower surface of the pressure plate 10 to clamp the thread. The suction mounting portion 9b has a through hole 9c, and a suction pipe 11 is installed inside the through hole 9c for sucking away and cleaning the cut thread ends.

[0030] After sewing is completed, the drive rod of the first cylinder 5 extends, causing the hook 7 to move diagonally downwards, so that the hook part 7a of the hook 7 hooks the top thread between the needle and the fabric. Then, the drive rod of the first cylinder 5 retracts, causing the hook 7 to move diagonally upwards, and the hook part 7a pulls the top thread back. The hook part 7a cooperates with the lower surface of the pressure plate 10 to clamp the top thread. The thread end is fixed on the hook part 7a, which can prevent bird's nests when starting the next stitch.

[0031] like Figure 4 and Figure 5 As shown, the thread cutting mechanism includes a second fixed seat 12 fixed to the front side of the sewing machine housing 1, a second cylinder 13 vertically mounted on the second fixed seat 12, a second connecting plate 14 mounted on the drive rod of the second cylinder 13, a third connecting plate 15 connected to the front end of the second connecting plate 14, and a second mounting plate 16 provided on the front side of the third connecting plate 15.

[0032] The second connecting plate 14 has a second adjusting groove 14a and a third adjusting groove 14b, which are arranged in parallel. A second screw passes through the second adjusting groove 14a and is connected to the third connecting plate 15, and a third screw passes through the third adjusting groove 14b and is connected to the third connecting plate 15. By adjusting the position of the second screw in the second adjusting groove 14a and the position of the third screw in the third adjusting groove 14b, the rotation angle of the third connecting plate 15 can be adjusted.

[0033] A first mounting base 17 is installed at the front end of the second fixed base 12. A first connecting block 18 is slidably installed at the front end of the first mounting base 17. The top of the first connecting block 18 is fixedly connected to the second connecting plate 14. A first guide rail 19 is vertically installed at the front end of the first mounting base 17. A first slider that cooperates with the first guide rail 19 is installed on the rear side of the first connecting block 18. The first connecting block 18 can move up and down along the first guide rail 19. The drive rod of the second cylinder 13 drives the second connecting plate 14 to move up and down along the first guide rail 19. The tangent mechanism can avoid interference with other mechanisms.

[0034] A third mounting plate 20 is slidably mounted on the front side of the second mounting plate 16. A second guide rail 21 is obliquely mounted on the front side of the second mounting plate 16. A second slider that cooperates with the second guide rail 21 is provided on the rear side of the third mounting plate 20. The third mounting plate 20 moves obliquely relative to the second mounting plate 16 along the second guide rail 21.

[0035] A third cylinder 22 is provided obliquely downward on the front side of the second mounting plate 16. The cylinder body of the third cylinder 22 is fixed to the front side of the second mounting plate 16 by the third cylinder mounting bracket 23. The drive rod of the third cylinder 22 is fixedly connected to the third mounting plate 20. The drive rod of the third cylinder 22 can drive the third mounting plate 20 to move obliquely upward and downward along the second slide rail.

[0036] The third mounting plate 20 is provided with a rotatable cutting handle 24. The third mounting plate 20 is rotatably mounted with a first mounting block 26 via a first rotating shaft 25. A second mounting block 27 is mounted on the lower end of the first mounting block 26. The lower end of the first mounting block 26 has an upper recess 26a, and the upper end of the second mounting block 27 has a lower recess 27a. A space for mounting the cutting handle 24 is formed between the upper recess 26a and the lower recess 27a. The end of the cutting handle 24 is provided with a cutter 28. The cutter 28 is mounted at a certain angle to the end of the cutting handle 24, so that the blade of the cutter 28 is close to the surface line and accurately cuts the surface line.

[0037] The third mounting plate 20 is provided with a fourth adjustment groove 20a, and a fourth screw 29 is installed in the fourth adjustment groove 20a. A fifth screw 30 is installed on the first mounting block 26. One end of the tension spring 31 is connected to the fourth screw 29, and the other end of the tension spring 31 is connected to the fifth screw 30. When the third cylinder 22 drives the cutting handle 24 to perform the cutting operation, the cutting handle 24 will pull the tension spring 31 to generate a restoring force. Under the action of the restoring force, the cutting handle 24 tends to rotate to the right with the first rotating shaft 25, so that the cutting blade 28 at the end of the cutting handle 24 is in close contact with the surface thread between the hook 7 and the needle and cuts the surface thread.

[0038] like Figure 6 As shown, the thread control mechanism includes a third fixed seat 32 fixed to the upper end of the sewing machine housing 1. An extension seat 33 is installed at the right end of the third fixed seat 32. A thread control rod 34 is rotatably installed on the extension seat 33. A thread take-up part 34a is made at the bottom of the thread control rod 34. The thread take-up part 34a has a through hole for the top thread to pass through.

[0039] A fourth cylinder 35 is mounted on the third fixed base 32. The drive shaft of the fourth cylinder 35 is connected to a first connecting member 37. A spring 36 is fitted on the drive shaft of the fourth cylinder 35. One end of the spring 36 abuts against the cylinder body of the fourth cylinder 35, and the other end abuts against the first connecting member 37. One end of the first connecting member 37 is connected to the drive shaft of the fourth cylinder 35, and the other end of the first connecting member 37 is rotatably connected to one end of the second connecting member 38. The other end of the second connecting member 38 is rotatably connected to one end of the third connecting member 39, and the other end of the second connecting member 38 and the third connecting member 39 form an angle. A second rotating shaft 40 is provided at the other end of the third connecting member 39. The second rotating shaft 40 is rotatably mounted in the extension base 33, and the control rod 34 is fixedly mounted on the end of the second rotating shaft 40.

[0040] The drive rod of the fourth cylinder 35 extends, causing the first connecting member 37 to move to the right. The first connecting member 37 pushes the second connecting member 38 to rotate, reducing the angle between the second connecting member 38 and the third connecting member 39. The second connecting member 38 then drives the third connecting member 39 to rotate to the right, and the second rotating shaft 40 drives the control rod 34 to rotate to the left, lowering the control rod 34, at which point the top thread is in a relaxed state. The drive rod of the fourth cylinder 35 retracts, causing the first connecting member 37 to move to the left. The angle between the second connecting member 38 and the third connecting member 39 increases, causing the second connecting member 38 to rotate the third connecting member 39 to rotate to the left. The second rotating shaft 40 then drives the control rod 34 to rotate to the right, raising the control rod 34, at which point the top thread is in a taut state.

[0041] When sewing begins, the second cylinder 13 drives the second mounting plate 16 to be positioned downwards, at which time the thread end on the needle is clamped between the hook part 7a and the lower surface of the pressure plate 10.

[0042] Before the first stitch is sewn, the fourth cylinder 35 in the thread control mechanism drives the thread control lever 34 to lower, loosening a small amount of top thread. After the first stitch is sewn, the third cylinder 22 in the thread cutting mechanism drives the cutter 28 at the end of the thread cutting handle 24 to cut the top thread between the thread hook 7 and the needle. The suction pipe 11 in the hooking mechanism picks up the cut thread end, and then the fourth cylinder 35 in the thread control mechanism drives the thread control lever 34 to raise, tightening a small amount of top thread. After the sewing is completed, the first cylinder 5 in the hooking mechanism drives the rod to extend, causing the hooking part 7a of the thread hook 7 to hook the top thread on the needle. Then the first cylinder 5 drives the rod to retract, fixing the top thread between the hooking part 7a and the lower surface of the pressure plate 10. The above steps are repeated when sewing the next piece of fabric.

[0043] The preferred embodiment of this utility model has been described, and various changes or modifications made by those skilled in the art will not depart from the scope of this utility model.

Claims

1. A bird nest prevention device for a sewing machine, comprising a sewing machine housing (1), wherein the sewing machine housing (1) is equipped with a hooking mechanism for hooking and clamping the thread, and a cutting mechanism for cutting the thread, characterized in that: The sewing machine housing (1) is equipped with a thread control mechanism for controlling the tension of the face thread. The thread control mechanism includes a third fixed seat (32) fixed to the upper end of the sewing machine housing (1). The third fixed seat (32) is provided with a second rotating shaft (40) that can rotate. The second rotating shaft (40) is connected to a thread control rod (34). The thread control rod (34) is provided with a thread take-up part (34a) for threading the face thread. The third fixed seat (32) is equipped with a fourth cylinder (35) for driving the thread control rod (34) to swing around the center line of the second rotating shaft (40).

2. The bird nest prevention device according to claim 1, characterized in that: An extension seat (33) is installed on the right end of the third fixed seat (32), and the second rotating shaft (40) is rotatably installed on the extension seat (33); a spring (36) for resetting is sleeved on the drive shaft of the fourth cylinder (35); the drive shaft of the fourth cylinder (35) is connected to a first connecting member (37), the first connecting member (37) is rotatably connected to a second connecting member (38), and the second connecting member (38) drives the second rotating shaft (40) to rotate through the third connecting member (39).

3. The bird nest prevention device according to claim 1, characterized in that: The thread cutting mechanism includes a second fixed seat (12) fixed to the front side of the sewing machine housing (1). The front side of the second fixed seat (12) is provided with a second mounting plate (16) that can be raised and lowered. The front side of the second mounting plate (16) is provided with a third mounting plate (20) that can move obliquely. The third mounting plate (20) is connected to the first mounting block (26) through a tension spring (31). The third mounting plate (20) is rotatably mounted with the first mounting block (26) through a first rotating shaft (25). The lower end of the first mounting block (26) is provided with a second mounting block (27). A thread cutting handle (24) is fixed between the first mounting block (26) and the second mounting block (27). The end of the thread cutting handle (24) is provided with a cutter (28).

4. The bird nest prevention device according to claim 3, characterized in that: The hook mechanism includes a first fixed seat (2) fixed to the sewing machine housing (1), a first mounting plate (4) is provided at the front end of the first fixed seat (2), a hook (7) is obliquely provided on the front side of the first mounting plate (4), a hook part (7a) is provided at the front end of the hook (7), an inclined connecting rod part (4a) is provided at the lower end of the first mounting plate (4), and a connecting seat (9) for guiding the movement of the hook (7) is fixed at the end of the connecting rod part (4a).

5. The bird nest prevention device according to claim 4, characterized in that: The lower end of the first mounting block (26) has an upper recess (26a), and the upper end of the second mounting block (27) has a lower recess (27a). A space for mounting the tangent shank (24) is formed between the upper recess (26a) and the lower recess (27a).

6. The bird nest prevention device according to claim 5, characterized in that: The second fixed seat (12) is vertically mounted with a second cylinder (13), the drive rod of the second cylinder (13) is mounted with a second connecting plate (14), the front end of the second connecting plate (14) is mounted with a third connecting plate (15), and the third connecting plate (15) is connected to the second mounting plate (16); the front side of the second mounting plate (16) is obliquely downward with a third cylinder (22), the drive rod of the third cylinder (22) is fixedly connected to the third mounting plate (20); the front end of the second fixed seat (12) is mounted with a first mounting seat (17), the front end of the first mounting seat (17) is slidably mounted with a first connecting block (18) through a first guide rail (19), and the top of the first connecting block (18) is fixedly connected to the second connecting plate (14).

7. The bird nest prevention device according to claim 6, characterized in that: The second connecting plate (14) has a second adjusting groove (14a) and a third adjusting groove (14b) arranged in parallel. The second adjusting groove (14a) and the third adjusting groove (14b) are arranged in parallel. A second screw passes through the second adjusting groove (14a) and is connected to the third connecting plate (15). A third screw passes through the third adjusting groove (14b) and is connected to the third connecting plate (15).

8. The bird nest prevention device according to claim 7, characterized in that: The third mounting plate (20) is provided with a fourth adjustment groove (20a), and a fourth screw (29) is installed in the fourth adjustment groove (20a); the first mounting block (26) is equipped with a fifth screw (30); one end of the tension spring (31) is connected to the fourth screw (29), and the other end of the tension spring (31) is connected to the fifth screw (30).

9. The bird nest prevention device according to claim 8, characterized in that: The connecting seat (9) has a hook mounting part (9a) and a suction mounting part (9b). The hook (7) is slidably mounted between the lower surface of the connecting rod part (4a) and the upper surface of the hook mounting part (9a). A pressure plate (10) is installed at the end of the connecting rod part (4a). The lower surface of the pressure plate (10) cooperates with the hook part (7a) to clamp the face line. The suction mounting part (9b) has a through hole (9c). A suction pipe (11) is installed in the through hole (9c).

10. The bird nest prevention device according to claim 9, characterized in that: The front side of the first fixed base (2) is connected to the first mounting plate (4) through the first connecting plate (3). The first connecting plate (3) has a first adjusting groove (3a). The first screw passes through the first mounting plate (4) and is fixed in the first adjusting groove (3a).

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