Thread pulling device for sewing machine

Abstract

The utility model discloses a thread feeding and pulling device of sewing machine, compared with the past, eliminate the problem that the adjustment of the thread puller is difficult due to the shift of the front and back positions of the shaft of the rotary solenoid, and the problem that the right thread of the sewing machine with multiple needles arranged in the left and right directions cannot be captured due to thread shaking. The thread feeding and pulling device comprises: a thread puller (37) that reciprocates left and right below the eye of the multiple needles arranged left and right; and a linear motion type pull solenoid (4) as a driving source for driving the thread puller (37). In addition, the sliding part (341) of the slide block holder (34) fixed to the base end of the thread puller is formed in an arc shape.

Description

Technical Field

[0001] This utility model relates to a thread-pulling device for a sewing machine. In this utility model, "front and back" refers to the front-to-back direction of the fabric feeding direction, and "left and right" refers to the left-to-right direction when viewing the sewing machine from the front. Additionally, "up and down" refers to the up-and-down direction of the sewing machine. Background Technology

[0002] As a conventional thread-pulling device for sewing machines, there are known thread-pulling devices that include a rotating solenoid and a puller that reciprocates therefrom (see, for example, Patent Document 1). This thread-pulling device, for example in a flat-locked interlocking sewing machine, after the thread (also called needle thread) is cut below the needle plate using a known thread-cutting device at the end of one sewing cycle, pulls up and holds the remaining portion of the thread extending downwards from the eye of the needle waiting above the needle plate. This facilitates insertion into the fabric at the start of sewing. Furthermore, during subsequent sewing, the remaining portion of the thread extending downwards from the needle plate is sewn in, preventing it from excessively protruding from the front of the stitch on the inside of the fabric.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Published Patent No. 63-042948 Utility Model Content

[0006] The problem to be solved by utility models

[0007] In conventional technology, a rotary solenoid was used as the drive mechanism for the thread puller. However, a rotary solenoid is a structure that converts the linear force of its shaft into rotational motion, and this rotational motion is accompanied by a slight axial movement. This is the main reason why the thread puller performs a slight back-and-forth movement while simultaneously performing a reciprocating motion in the left-right direction. In a flatbed interlocking sewing machine, multiple needles are arranged vertically at equal intervals in the left-right direction, and because the back-and-forth position of the thread puller is adjusted in conjunction with one thread, the back-and-forth position shifts relative to the other threads, making adjustment difficult.

[0008] Furthermore, in conventional technology, the thread puller moves roughly horizontally left and right below the needle eye to capture the thread, and after capturing all the thread, it moves diagonally upward to separate from the needle and wait. In a flatbed interlocking sewing machine, multiple needles are arranged vertically at equal intervals in the left-right direction, and the needle height increases in a stepped manner starting from the left needle. Therefore, when the thread puller moves roughly horizontally left and right, the distance from the needle eye of the left needle is greater than the distance from the needle eye of the right needle. Moreover, when the remaining portion of the thread extending from the inside of the needle eye towards the bottom of the needle plate causes thread swaying in the front-back direction, the swaying amplitude is greater the further away from the needle eye. When the thread puller captures this portion, sometimes it can capture the thread on the left but cannot capture the thread on the right.

[0009] The present invention addresses the problem of providing a thread puller for a sewing machine that eliminates the aforementioned problems of difficulty in adjusting the thread puller due to front-to-back position offset and inability to capture the right-side thread due to thread wobbling.

[0010] Methods for solving problems

[0011] To achieve the above objectives, the sewing machine thread pulling device of the utility model described in technical solution 1 comprises: a thread puller that reciprocates below multiple needles; and a drive source that drives the thread puller. The sewing machine thread pulling device uses the thread puller to catch and hold the upper thread of the thread cut by the thread cutting device at the end of sewing. The drive source is a linear motion type pull solenoid.

[0012] To achieve the above objectives, the utility model described in technical solution 2 is based on the sewing machine thread pulling device described in technical solution 1. The sewing machine thread pulling device comprises: a planar base configured parallel to the linearly moving axis of the solenoid and fixedly connected to the solenoid; a joint connector connected to the front end of the solenoid axis; a crank connected to the joint connector and capable of swinging at its front end; a thread pulling shaft, one end of which is fixedly connected to the base end of the crank and supported on the base in a manner rotatable about the axis; a rod, one end of which is fixedly connected to the other end of the thread pulling shaft; a slider holder, one end of which is fixedly connected to the base end of the thread puller, and the other end of which forms a sliding portion, and the other end of the rod is rotatably connected to the middle portion of the slider holder along its length; and a guide shaft that slides on the sliding portion of the slider holder and is supported on the base in a manner rotatable about the axis.

[0013] To achieve the above objectives, the utility model described in technical solution 3 is based on the sewing machine thread pulling device described in technical solution 2, characterized in that the sliding part of the slider holder is formed in an arc shape, and the sliding part passes through the guide hole provided in the orthogonal direction of the guide shaft.

[0014] To achieve the above objectives, the utility model described in technical solution 4 is based on the sewing machine thread pulling device described in technical solution 3, characterized in that the sewing machine thread pulling device includes a guide shaft support plate that supports the other end of the guide shaft so that it can rotate around the shaft.

[0015] Utility Model Effect

[0016] The sewing machine thread puller according to this utility model can eliminate the aforementioned problems such as difficulty in adjusting the thread puller due to front-to-back position offset and inability to capture the upper thread on the right side due to thread wobbling.

[0017] According to the aforementioned technical solution 1, the sewing machine's thread pulling device comprises: a thread puller that reciprocates below multiple needles; and a drive source that drives the thread puller. The sewing machine's thread pulling device uses the thread puller to catch and hold the upper thread of the thread cut by the thread cutting device at the end of sewing. The characteristic is that the drive source is a linear motion type pull solenoid, thereby avoiding slight forward and backward movement like that of a rotating solenoid. The forward and backward position does not shift when the thread puller moves left and right, thus facilitating position adjustment.

[0018] Further according to technical solution 2, the sewing machine's thread pulling device comprises: a planar base configured parallel to the linearly moving axis of the solenoid and fixedly connected to the solenoid; a joint connected to the front end of the solenoid axis; a crank connected to the joint and capable of swinging at its front end; a thread pulling shaft, one end of which is fixedly connected to the base end of the crank and supported on the base in a manner rotatable about the axis; a rod, one end of which is fixedly connected to the other end of the thread pulling shaft; a slider holder, one end of which is fixedly connected to the base end of the thread puller and the other end of which forms a sliding portion, and the other end of the rod is rotatably connected to the middle of the length direction of the slider holder; and a guide shaft that slides on the sliding portion of the slider holder and is supported on the base in a manner rotatable about the axis. Therefore, as mentioned above, there is no slight forward or backward movement like that of a rotating solenoid. The forward or backward position does not shift when the thread puller moves left or right, so the position can be easily adjusted. In addition, the movement of the thread puller can be further set to move left or right at the position where it captures the thread below the eye of multiple needles, and after capturing all the thread, it moves diagonally upward to separate from the needle and stand by.

[0019] Further according to technical solution 3, the sliding part of the slider holder is formed in an arc shape, and the sliding part passes through the guide hole provided in the orthogonal direction of the guide shaft. Therefore, the movement of the thread puller is not set to a roughly horizontal movement below multiple needles as in conventional technology, but rather a sloped movement from the left stop point to the right. Thus, when the thread puller captures the upper thread on the right side, it is positioned close to the eye of the needle on the right side, and even when the thread wobbles, it can capture the upper thread on the right side to the same extent as the upper thread on the left side.

[0020] Further according to technical solution 4, the sewing machine's thread pulling device is characterized in that it has a guide shaft support plate that supports the other end of the guide shaft and is rotatable around the shaft, thereby enabling the guide shaft to be supported at both ends by a base and the other end by the guide shaft support plate. Attached Figure Description

[0021] Figure 1 This is a perspective view of the thread pulling device of the sewing machine applied to this utility model, viewed from the left front. The positive direction of the X-axis represents the right direction, the positive direction of the Y-axis represents the rear direction, and the positive direction of the Z-axis represents the upward direction.

[0022] Figure 2 This is an exploded view from the left front of the sewing machine to which this invention is applied.

[0023] Figure 3 This is an exploded view taken from the right rear of the sewing machine to which this invention is applied.

[0024] Figure 4 This is a front view of the thread puller at the left stop point of the thread pulling device of the sewing machine applied to this utility model.

[0025] Figure 5 This is a front view of the thread puller at the right stop point of the thread pulling device of the sewing machine applied to this utility model.

[0026] Explanation of reference numerals in the attached figures

[0027] 1. Sewing machine

[0028] 2-wire cutting device

[0029] 3. Cable pulling device

[0030] 4. Pull-type solenoid

[0031] 10 needles

[0032] 11 needle plate

[0033] 12 presser feet

[0034] 30 bases

[0035] 31. Top-line pull-out spool

[0036] 32 strokes

[0037] 33 rings

[0038] 34 with slider cage

[0039] 35 Guide shaft

[0040] 36 Guide shaft support plate

[0041] 37. Cable puller

[0042] 40 Coil Base

[0043] 41 coils

[0044] 42 brackets

[0045] 43. Pull-type solenoid shaft

[0046] 44 Joints

[0047] 45 Crank

[0048] 46. ​​Tension coil spring

[0049] 47 Limiters

[0050] 48 Flange bushing

[0051] 341 Sliding part

[0052] 351 Guide Hole

[0053] 371 hooks

[0054] 372 Leaf spring. Detailed Implementation

[0055] The following is based on Figures 1 to 5 An example of an embodiment of this utility model will be described. Figure 1 This is a perspective view from the left front of the sewing machine according to the present invention, where the positive direction of the X-axis represents the right direction, the positive direction of the Y-axis represents the rear direction, and the positive direction of the Z-axis represents the upward direction. In this embodiment, a flat interlocking sewing machine with 3 needles is used, but it can also be a sewing machine with 2 needles, 4 needles, etc. The sewing machine 1 is equipped with a thread cutting device 2 and a thread pulling device 3. When the sewing machine 1 is stopped after the prescribed sewing is completed, the needle 10 is waiting at the upper stop point above the needle plate 11. At this time, the upper thread (not shown) passing through the multiple needles 10, as is well known, passes through the needle eye of the needle 10, through the needle drop hole of the presser foot 12 located below, through the fabric, and through the needle drop hole of the needle plate 11 below it. It is wound around the main body of the curved needle (not shown) waiting below it and extends upward, connecting with the rear end of the stitch on the fabric above the needle plate. As is well known, the thread cutting device 2 operates between the needle plate 11 and the looper, cutting the lower and upper threads between the needle plate 11 and the looper. When the upper thread is pulled from above the presser foot 12 in this state, the end of the cut upper thread extending below the needle plate 11 can be pulled upwards towards the presser foot 12. The thread pulling device 3, as is well known, pulls up the end of the upper thread.

[0056] Figure 2 This is an exploded view from the left front of the thread-pulling device of the sewing machine applied to this utility model. Figure 3 This is an exploded view from the right rear of the sewing machine according to the present invention, showing the thread pulling device 3. The thread pulling device 3 of this embodiment has the following structure: The base 30 is planar, i.e., plate-shaped, and is fixed to the sewing machine 1 by screws on the right side of the plurality of needles 10. The thread pulling shaft 31 is configured with its axial direction in the front-back direction, passes through a hole provided in the base 30, and is rotatable.

[0057] Pull-type solenoid 4 ( Figure 3The device comprises a coil base 40, a coil 41, a pull-type solenoid shaft 43, and a tension helical spring 46, and is disposed on the back side of the base 30 and fixedly connected thereto. The coil base 40 is provided with a screw hole and is fixedly connected to the base 30 by screws. The coil 41 is a structure in which a wire is wound around a coil frame and passes through a hollow shaft portion protruding from the coil base 40. The bracket 42 is in the shape of a curved plate and, together with the aforementioned coil base 40, clamps the coil 41 and is fixedly connected to the base 30 by screws, thereby also fixing the coil 41. The pull-type solenoid shaft 43 is a movable iron core that passes through the coil 41. A joint 44 is fixedly connected to a threaded shaft portion provided at the front end of the pull-type solenoid shaft 43.

[0058] The flanged bushing 48 is fixed to a hole provided in the base 30 from the back side of the base 30 by screws. The upper wire pulling shaft 31 has one end facing rearward and the other end facing frontward, and passes through the flanged bushing 48 in a rotatable manner, thereby being supported on the base 30 in a rotatable manner about its axis. The flanged bushing 48 has bushing portions on both sides of the flange portion. In addition, the upper wire pulling shaft 31 is a shaft with a base, and is configured such that the seat surface of the other front end of the upper wire pulling shaft 31 slides against the end face of the bushing portion on the front surface side of the flanged bushing 48.

[0059] The crank 45 has a shaft hole at its base end, through which the rear end of the upper wire pulling shaft 31 passes and is fixed to the crank 45. Furthermore, the front side of the crank 45 slides against the end face of the bushing portion on the back side of the flanged bushing 48, thereby configuring it to swing in conjunction with the upper wire pulling shaft 31. A pin is provided near the front end of the crank 45, sliding in a groove provided in the aforementioned joint joint 44, thereby configuring it to connect with the joint joint 44. A tension coil spring 46, in an initial tension state, is engaged with a hook provided at the other end of the aforementioned crank 45 and a hole provided in the bracket 42.

[0060] Therefore, when the coil 41 is not energized, the crank 45, using the force of the tension spring 46, swings the pull solenoid shaft 43 away from the coil 41 via the articulated joint 44. The limiter 47 is fixed to the base 30 on the left side of the articulated joint 44 with screws, preventing the articulated joint 44 from moving in this state. When the coil 41 is energized, the pull solenoid shaft 43 is pulled in, causing the crank 45 to swing against the force of the tension spring 46 via the articulated joint 44, thus causing the upper wire pulling shaft 31 to swing.

[0061] Rod 32 ( Figure 2One end of the rod 32 is fixed to the other end of the upper wire pulling shaft 31 with a screw. Therefore, the rod 32 swings as the upper wire pulling shaft 31 swings. A hole is provided at the other end of the rod 32 for the collar 33 to pass through. The rod 32 slides relative to the collar 33. The base end of the wire puller 37 is fixed to the left end of the slider holder 34 with a screw, and a sliding part 341 protrudes from the right end of the slider holder 34. Furthermore, a screw hole is provided in the middle of the slider holder 34, and the aforementioned collar 33 is fixed to it with a screw. Thus, the slider holder 34 and the other end of the rod 32 are connected to each other in a rotatable manner via the collar 33.

[0062] The guide shaft 35 is supported so that it can rotate about the shaft by sliding through a shaft hole provided in the base 30 at one end. In addition, the guide shaft 35 is provided with a guide hole 351 in the orthogonal direction of the shaft, and the sliding part 341 of the aforementioned slider holder 34 slides through the guide hole 351.

[0063] The guide shaft support plate 36 is a Z-shaped curved plate with a shaft hole on one end. The end without the shaft hole is fixed to the base 30 with screws. The other end of the guide shaft 35 slides through the guide shaft support plate 36 in a rotatable manner and is supported to rotate about the axis. Thus, one end of the guide shaft 35 is supported on the base 30, and the other end is supported on the guide shaft support plate 36, forming a two-end support. Therefore, the load on the shaft and shaft hole is reduced compared to a cantilever support.

[0064] The wire puller 37 has a hook 371 and a leaf spring 372. The front end of the hook 371 is hook-shaped, and its base is fixed to the left end of the slider holder 34 by a screw. One end of the leaf spring 372 is fixed to a screw hole provided in the middle of the hook 371 by a screw, and the other end covers the hook-shaped part at the front end of the hook 371. Thus, the wire caught at the hook-shaped part at the front end of the hook 371 can be held and maintained by the leaf spring 372 and the hook 371.

[0065] Figure 4 This is a front view of the thread puller at the left stop point of the thread pulling device of the sewing machine applied to this utility model. The thread pulling device 3 operates as follows. When the sewing machine 1 stops at the end of the prescribed sewing, the needle 10 is waiting at the top stop point. Next, the thread cutting device 2 operates and cuts the thread held in the loop below the needle plate 11. Afterwards, the thread puller 37, which is waiting at the right stop point above and to the right of the multiple needles 10 arranged on the left and right, is guided by the sliding part 341 that slides with the rotating guide shaft 35 due to the swing of the rod 32, and at the same time, the sliding block holder 34 linked to the rod 32 moves to the left, thereby moving the thread puller 37 to the left stop point below and to the left of the multiple needles 10.

[0066] In this embodiment, the puller 37 has a height close to the eye of the needle 10 on the left at the right stop, but descends to near the front end of the needle 10 on the left at the left stop. During the movement of the puller 37 from the right stop to the left stop, relative to the upper line extending downward from the eye of the multiple needles 10, the puller 37 only makes the front side of the front end of the hook 371 contact the upper line, without capturing the line.

[0067] Figure 5 This is a front view of the thread puller at the right stop point of the thread puller device of the sewing machine applied to this utility model. After the above-described action, the lever 32 swings in the opposite direction, and the thread puller 37 moves from below to the left of the left stop point of the multiple needles 10 to above and to the right of the right stop point. At this time, the thread extending downward from the needle eye of the multiple needles 10 enters the hook-shaped part at the front end of the hook 371 and is captured sequentially from left to right. As mentioned above, the swing of the lever 32 is caused by the rotation of the thread puller shaft 31 of the lever 32. In addition, the thread puller shaft 31 is a base shaft, and the base surface slides against the end face of the bushing portion on the front surface side of the flange bushing 48, and this action does not produce movement in the back-and-forth direction.

[0068] In conventional technology, the movement of the thread puller 37 is generally horizontal, moving left to right, below the multiple needles 10. In this embodiment, the slider holder 34 has a protruding, arc-shaped sliding portion 341. Therefore, when the thread puller 37 moves relative to the multiple needles 10 from the lower left to the upper right, this movement can be configured as a sloped movement from the left stop point to the upper right (in... Figure 5 (In the image, for reference, the movement of the front end of the puller 37 is shown in stages). Therefore, compared with the previous technology, when the puller 37 captures the upper thread on the right, it is located close to the eye of the needle 10 on the right, and even when the thread wobbles in the front-back direction, it can capture the upper thread on the right to the same extent as the upper thread on the left.

[0069] According to the above description of the sewing machine's thread pulling device, the sewing machine's thread pulling device includes: a thread puller that reciprocates below multiple needles; and a drive source that drives the thread puller. The thread pulling device uses the thread puller to catch and hold the upper thread of the thread cut by the thread cutting device at the end of sewing. The characteristic is that the drive source is a linear motion type pull solenoid, so that there is no slight back-and-forth movement like a rotating solenoid. The front-and-back position does not shift when the thread puller moves left and right, so the position can be easily adjusted.

[0070] This invention is not limited to the embodiments described above. Anyone skilled in the art can make various modifications to the above embodiments without departing from the spirit of this invention, and this invention also includes these modifications. Furthermore, this embodiment uses a flat interlocking sewing machine, but it is not limited to this; for example, it can also be implemented using a multi-needle double-thread lockstitch sewing machine, etc.

Claims

1. A thread-pulling device for a sewing machine, comprising: A thread puller that reciprocates beneath multiple needles; and The driving source drives the cable puller. The sewing machine's thread puller catches and holds the upper thread of the thread cut by the thread cutting device at the end of sewing. Its features are, The driving source is a linear motion type pull solenoid.

2. The thread pulling device for a sewing machine according to claim 1, characterized in that, The sewing machine's thread pulling device includes: A planar base is configured to be parallel to the axis of the solenoid, which is in linear motion, and the solenoid is fixedly connected to it. A joint connector, which is connected to the front end of the pull solenoid shaft; A crank, which is connected to the joint and whose front end is capable of swinging; The upper wire pulling shaft has one end fixed to the base end of the crank and is supported on the base in a manner that allows it to rotate about the shaft; A rod, one end of which is fixed to the other end of the upper wire pulling shaft; A slider holder has a base end of the puller fixed to one end and a sliding portion formed at the other end. The other end of the rod is rotatably connected to the middle portion of the slider holder in the longitudinal direction. as well as A guide shaft slides on the sliding portion of the slider holder, and one end is supported on the base in a manner that allows it to rotate about the shaft.

3. The thread pulling device for a sewing machine according to claim 2, characterized in that, The sliding portion of the slider holder is formed in an arc shape, and the sliding portion passes through a guide hole provided in the orthogonal direction of the guide shaft.

4. The thread pulling device for a sewing machine according to claim 3, characterized in that, The sewing machine's thread pulling device includes a guide shaft support plate that supports the other end of the guide shaft and allows it to rotate around the shaft.

Images