TWI565848B - Sewing machine 's thread cutter and tangent method - Google Patents

Description

Dialing cutter for sewing machine and cutting method thereof

The invention relates to a tangential device, in particular to a plucking cutter for traversing a needle stitching line during shearing to extend the stitching of the bur and thereby preventing the stitching of the styling needle from loosening and a tangential cutting method thereof.

At present, the sewing machine on the market usually carries a set of automatic thread cutting devices, so that the sewing operation can be automatically cut off after the sewing operation is completed, thereby effectively simplifying and shortening the sewing operation time. For example, the "cutting device for sewing machine" of the Republic of China Invention Patent No. I391547 discloses a tangential device having a movable blade and a fixed blade. The movable blade includes a stitching bottom line catching portion and a line catching portion, and the movable blade can reciprocate between a forward position and a retracted position. When the sewing operation is stopped, the movable blade advances toward the advanced position and causes the sewing bottom thread catching portion and the upper thread catching portion to enter between a needle plate and a looper. Then, the movable blade retreats toward the retracted position, and the suture bottom line capturing portion and the upper thread catching portion respectively capture a stitching bottom line and a double line. Finally, the movable blade can shear the sewing bottom line and the double-sided line in cooperation with the fixed blade.

Although the conventional tangential device has the function of automatically cutting the suture, it is still not perfect in practical use. Specifically, FIG. 1 is a half finished product 10 for sewing work using one or three vehicles, and the semi-finished product 10 includes a three-thread thread 11, a bottom thread 12, and a fabric 13. Wherein, the three-needle thread 11 leaves a reserved line segment of the same length on the front surface of the cloth 13 by cutting the movable blade with the fixed blade. Referring to FIG. 2-1 and FIG. 2-2, after the cloth 13 is dyed, washed or stretched, the reserved line segment of the three-needle thread 11 exposed on the front surface of the cloth 13 will expand with the cloth 13 . The degree is shortened. If the stretched amount of the cloth 13 is larger than the reserved line segment of the three-needle thread 11, the three-needle thread 11 will be separated from the bottom thread 12 and loosened to the opposite side of the cloth 13, and the dotted line portion of the three-needle thread 11 in FIG. That is, the three-needle thread 11 is loosened to the line segment on the reverse side of the cloth 13. At this time, if the bottom thread 12 is pulled, the bottom thread 12 and the three needle thread 11 cannot be cross-knotted, and the bottom thread 12 and the three needle thread 11 are loosened. Therefore, how to better design and solve the conventional tangential device has become a problem to be solved because the remaining reserved line segment length is insufficient and the needle thread is loose.

The main object of the present invention is to solve the problem that the conventional tangential device cannot effectively extend the remaining line segments remaining in the needle thread to prevent the needle thread from coming loose.

In order to achieve the above object, the present invention provides a thread cutting knife for a sewing machine, the sewing machine having a plurality of needles for respectively pulling a needle stitch and performing a reciprocating lifting sewing stroke, and a pair of needles are disposed and pulled to the bottom. a lower hook of the reciprocating weaving stroke of the suture toward the locating needles, and a yoke disposed on the side of the lower yoke away from the stylus and cooperating with the plucking cutter to cut each crochet suture a fixed cutter with the bottom stitch, each of the burs pulling each of the bur stitches through a to-be-sewn in the reciprocating lift sewing stroke and performing the reciprocating weaving stroke with the lower hook The bottom stitching line forms a sewing web for fixing the object to be sewed, and an interlacing stitch formed by each of the burr stitch and the bottom stitch coil and connected to the woven mesh, the thread cutting knife The utility model is characterized in that the dial cutter comprises a first cutting edge portion, a second cutting edge portion which is arranged to be connected to the first cutting edge portion and protrudes away from the bur direction, and a second cutting edge portion away from the first cutting edge portion a dialing portion extending on one side of the portion, wherein the dial cutter is driven by the driver Having a reciprocating secant stroke toward the interlacing coil, and the plucking cutter has a threading state in which the interlacing coil is extended toward the interlacing coil and protrudes through the interlacing coil, and the fixing is performed Trapping in the direction of the cutter, the plucking line is pulled by the plucking portion, and the bottom crease is pulled by the first blade portion, and the fixed blade is sequentially matched by the second blade portion and the first blade portion. Cutting each of the burr sutures and the bottom suture to form a margin line segment with respect to the sewn web and a tangent state of an end line segment connecting the margin line segments.

In the embodiment of the present invention, the first cutting edge portion includes a step of guiding the bottom stitch line and each of the burr stitches to be displaced between the first blade portion and the second blade portion in the threading state. First guiding surface.

In the embodiment of the present invention, the second cutting edge portion includes a second guiding surface for guiding each of the bur stitches between the second cutting edge portion and the dialing portion in the threading state.

In the embodiment of the present invention, the dialing portion includes a side facing the second blade portion and guiding each of the stylus stitches to the side of the dial portion away from the second blade portion in the threading state. The guiding surface, and a connecting guiding surface is disposed on a side of the line portion away from the second blade portion and pulling the hook surface of each of the bur stitches in the tangential state.

In an embodiment of the invention, the dial portion extends away from the second blade portion and forms an acute angle of less than 90 degrees with respect to the dial cutter.

In order to achieve the above object, the present invention provides a method for producing an end line segment after a tangential line by using a dial cutter, which is applied to a sewing machine having a plurality of vehicles for respectively pulling a needle stitch and performing a reciprocating lift sewing stroke. a pair of needles, a pair of needles that are disposed with a plurality of needles and a bottom stitch to perform a reciprocating threading stroke toward the needles, and a lower hook needle disposed away from the side of the needle and associated with the needle a line cutter cooperates with a fixed cutter for cutting each of the needle stitches and the bottom stitch, each of the needles pulling each of the needle stitches through a to-be-sewn in the reciprocating lift stitching stroke And the bottom stitch threaded by the lower hook needle for forming the reciprocating thread stroke to form a sewing net for fixing the object to be sewed, and a stitch formed by each of the bur stitch and the bottom stitch coil is connected and connected The interlacing coil of the sewn web, the method for generating the end line segment after the tangent by the dial cutter comprises the following steps: Step 1: using the dial cutter to perform a reciprocating secant stroke toward the interlacing coil and sequentially using the a first cutting edge on the thread cutting knife Guiding the bottom suture with each of the bur stitches, and then guiding each crochet suture by a second blade portion on the ripper cutter and a dial portion spaced apart from the second blade portion. Having the bottom stitch between the first blade portion and the second blade portion, and each of the locating stitches is located on a side of the dial portion away from the second blade portion; and step 2: driving the Performing the reciprocating tangential stroke in the direction of the fixed cutter, and pulling the bottom suture by the first cutting edge portion, and pulling each crochet suture with the plucking portion, and using the second cutting edge And the first cutting edge portion is sequentially interlaced with the fixed cutter, and each of the sewing thread and the bottom stitch is cut to form a margin line with respect to the sewing web and an end connecting the margin line Line segment.

In the embodiment of the present invention, the step 1 further includes a sub-step of guiding the displacement of each of the locating stitches between the dialing portion and the fixed cutter by using a guiding surface of the dialing portion. Step 2 further includes a sub-step of pulling each of the bur stitches by a hook surface of the dial portion.

The thread cutting cutter of the sewing machine of the present invention and the tangential cutting method thereof have the following advantages compared with the prior art: 1. When the dial cutter of the present invention is reset toward the fixed cutter, the dialing portion will pull each of the stylus seams The line and the first blade portion pull the bottom stitch. Finally, when the dial cutter is interlaced with the fixed cutter, each of the needle stitch and the bottom stitch are cut by the thread cutter and the fixed cutter. Accordingly, the present invention has more than one end line segment for each of the needle stitches, so that each of the needle stitches and the bottom stitch line are less prone to loosening after stretching. .

The detailed description and technical contents of the present invention will now be described as follows:

The invention relates to a thread cutting knife of a sewing machine and a cutting method thereof. First, please refer to FIG. 3, which is a schematic structural view of the dial cutter of the present invention. The dial cutter 2 is applied to a sewing machine (not shown). The sewing machine of the present invention can be one or three vehicles, but is not limited to this embodiment. Referring to FIG. 4 and FIG. 5-1, the sewing machine mainly includes a plurality of burs 31, a pair of lower hook pins 32 disposed on the burs 31, and a side disposed on the side of the lower hook pins 32 away from the stylus 31. The cutter 33 is fixed. Specifically, each of the burs 31 pulls a burr suture 34 and performs a reciprocating lift sewing stroke. The lower hook 32 pulls a bottom stitch 35 and performs a reciprocating weaving stroke in the direction of the needles 31. The fixed cutter 33 cooperates with the thread cutter 2 to cut each of the needle stitch 34 and the bottom stitch 35. Each of the burs 31 pulls each of the burs sutures 34 through a workpiece 4 to be sewn in the reciprocating lift sewing stroke, as shown in FIG. Each of the spurs 31 and the bottom splicing line 32 for the reciprocating weaving stroke of the lower crochet 32 forms a sewn web 36 for fixing the object to be sewed 4 and a stitch 34 for each of the burs. An interlacing coil 37 is formed that is looped around the bottom stitch 35 and joined to the sewn web 36.

Referring to FIG. 3 and FIG. 4, the dial cutter 2 includes a first blade portion 21, and a second blade portion 22 disposed adjacent to the first blade portion 21 and protruding away from the stylus 31. The second blade portion 22 is spaced apart from the first blade portion 21 side of the dial portion 23, and a connecting portion 24 disposed at the other end of the dial cutter 2 with respect to the first blade portion 21. The first blade portion 21 includes a first guiding surface 211. The second cutting edge portion 22 includes a second guiding surface 221 . The dial portion 23 extends away from the second blade portion 22 and forms an acute angle 231 of less than 90 degrees with respect to the dial cutter 2, and the dial portion 23 includes a direction facing the second blade portion 22. The guiding surface 232 is disposed, and a hooking surface 233 is connected to the guiding surface 232 and disposed on a side of the dialing portion 23 away from the second blade portion 22. Further, the hook surface 233 and the second blade are separated by a predetermined distance 234. The connecting portion 24 is coupled to a driving source (not shown) and provides a reciprocating secant stroke of the dial cutter 2 with respect to the fixed cutter 33. In this embodiment, the driving source may be a solenoid valve, or may be a driving device such as a motor or a cylinder, but is not limited to the above embodiment.

Please refer to FIG. 5-1 to FIG. 5-3 for the method of using the dial cutter 2 of the present invention. First, after the sewing machine finishes the sewing operation, the stylus 31 will be away from the interlacing coil 37, and the lower hook 32 will protrude from the interlacing coil 37. Further, when each of the burr suture 34 and the bottom suture 35 is to be cut, the driving source is only required to drive the ripper cutter 2 to perform the reciprocating secant stroke in the direction of the interlacing coil 37 and expand the The coil 37 is interleaved, and the dial cutter 2 is further protruded through the interlacing coil 37. In the present invention, the state in which the dial cutter 2 extends the interlacing coil 37 toward the interlacing coil 37 and protrudes through the interlacing coil 37 is a threading state, and the following is specifically described in the dial cutter 2; The process performed by the threading state. First, the first guiding surface 211 of the first blade portion 21 sequentially contacts each of the burr suture 34 and the bottom suture 35 to expand the interlacing coil 37. Then, each of the burr sutures 34 and the bottom sutures 35 are moved between the first blade portion 21 and the second blade portion 22 as the first guiding surface 211 is guided. Then, the second guiding surface 221 of the second blade portion 22 contacts each of the burr stitches 34 to open the interlacing coil 37. Then, each of the burr sutures 34 moves to the second blade portion 22 and the dial portion 23 as the second guiding surface 221 is guided. Then, the guiding surface 232 of the dial cutter 2 guides each of the yoke stitches 34 to the side of the dialing portion 23 away from the second blade portion 22, that is, the side of the hooking surface 233 or It is between the dial portion 23 and the fixed cutter 33.

Further, the present invention further defines that the state in which the dial cutter 2 performs the reciprocating tangential stroke in the direction of the fixed cutter 33 and leaves the interlacing coil 37 is a state of all lines, which is specifically described below in the dial cutter. 2 The process performed in this tangential state. The hook line surface 233 of the dial portion 23 pulls each of the burr stitches 34 toward the fixed cutter 33, and the first blade portion 21 pulls the bottom stitch line 35 toward the fixed cutter 33. . Then, when the second blade portion 22 is interlaced with the fixed cutter 33, each of the burr stitches 34 is cut by the second blade portion 22 and the fixed cutter 33. Finally, when the first blade portion 21 is interlaced with the fixed cutter 33, the bottom seam 35 is cut by the first blade portion 21 and the fixed cutter 33.

Referring to FIGS. 5-3 and 6, the interlacing coil 37 is cut by the dial cutter 2 and the fixed cutter 33, so that a margin to the sewn web 36 is formed on the object to be sewn 4. The line segment 38 and an end line segment 39 connecting the margin line segment 38. Further, in the present invention, because of the pulling of the dial portion 23 in the tangential state, the length of the line segment remaining in each of the burr sutures 34 is greater than the length of the end line segment 39 by conventional techniques. In other words, the length of the end line segment 39 is equal to the length of the predetermined distance 234. Referring to FIG. 7-1 and FIG. 7-2, after the workpiece 4 to be sewed, washed or stretched, each of the burr stitches 34 is exposed to the front of the object to be sewed 4 The line segment 38 and the end line segment 39 are shortened with the degree of expansion of the object to be sewed 4, but are not detached from the bottom stitching line 35 and still attached to the front surface of the object to be sewed 4, and Figures 7-1 and 7-2 The dotted line portion of each of the burr sutures 34 is a line segment in which each stylus suture 34 is pulled into the sewn web 36 and disappears, that is, each yech suture 34 is reserved. The line segment outside the sewn web 36 is shortened after being pulled. Therefore, if the bottom stitch 35 is pulled, the bottom stitch 35 and each of the needle stitches 34 are closely intertwined and knotted, thereby preventing the bottom stitch 35 from loosening with each of the stitches 34. The problem of taking off.

In summary, the present invention is a dial cutter for a sewing machine and a method of cutting the same, the dial cutter including a first blade portion, a second blade portion and a dial portion. The first blade portion, the second blade portion and the dial portion guide each of the plurality of vehicles when the dial cutter travels toward an interlacing coil formed by interlacing a plurality of needle stitches and a bottom stitch The needle stitch and the bottom stitch are between the first blade portion and the second blade portion and the side of the dial portion away from the second blade portion. When the dial cutter travels toward a fixed cutter disposed away from the interlacing coil, the dial portion pulls each of the bur stitches and the first blade portion pulls the bottom stitch. Finally, when the dial cutter is interlaced with the fixed cutter, each of the needle stitch and the bottom stitch are cut by the thread cutter and the fixed cutter. Accordingly, the present invention has more than one end line segment for each of the needle stitches, so that each of the needle stitches and the bottom stitch line are less prone to loosening after stretching. .

The present invention has been described in detail above, but the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Variations and modifications are still within the scope of the patents of the present invention.

10‧‧‧Semi-finished products
11‧‧‧Needle
12‧‧‧ bottom line
13‧‧‧ cloth
2‧‧‧Dial cutter
21‧‧‧First blade
211‧‧‧First guiding surface
22‧‧‧second blade
221‧‧‧second guiding surface
23‧‧‧Dial Department
231‧‧‧ acute angle
232‧‧‧ Guide surface
233‧‧‧Hook surface
234‧‧‧Predetermined distance
24‧‧‧Connecting Department
31‧‧‧ burs
32‧‧‧Unhook
33‧‧‧Fixed cutter
34‧‧‧needle stitching
35‧‧‧ bottom stitch
36‧‧‧Sewing weaving net
37‧‧‧Interwoven coil
38‧‧‧ Yuyu Line
39‧‧‧End line segment
4‧‧‧Stolen goods

Fig. 1 is a schematic view showing a semi-finished product of a sewing operation of the prior art of the present invention. 2-1 is a front elevational view showing the semi-finished product of the sewing operation of the prior art of the present invention after being stretched. 2-2 is a side view showing the semi-finished product of the sewing operation of the prior art of the present invention after being stretched. FIG. 3 is a schematic structural view of the wire cutter of the present invention. 4 is a schematic view showing the assembly of the wire cutter of the present invention. Figure 5-1 is a schematic view (1) of the tangential operation of the dial cutter of the present invention. Figure 5-2 is a schematic view of the tangential operation of the dial cutter of the present invention (2). Figure 5-3 is a schematic view of the tangential operation of the dial cutter of the present invention (3). Fig. 6 is a schematic view of the object to be sewed after the tangential cutting by the dial cutter of the present invention. Figure 7-1 is a front elevational view showing the object to be sewed after being tangentially cut by a dial cutter according to the present invention. Fig. 7-2 is a side view showing the workpiece to be sewed after being cut by a thread cutting knife according to the present invention.

2‧‧‧Dial cutter

21‧‧‧First blade

211‧‧‧First guiding surface

22‧‧‧second blade

221‧‧‧second guiding surface

23‧‧‧Dial Department

231‧‧‧ acute angle

232‧‧‧ Guide surface

233‧‧‧Hook surface

234‧‧‧Predetermined distance

Claims (10)

A thread cutting cutter for a sewing machine, the sewing machine having a plurality of needles for respectively pulling a needle stitch and performing a reciprocating lifting sewing stroke, and a pair of needles are arranged and pulling a bottom stitch toward the needles Performing a lower hook of a reciprocating weaving stroke, and a fixed cut disposed on the side of the lower hook away from the needle and engaging with the thread cutter to cut each of the needle stitches and the bottom stitch a knive, each of the burs pulling a sew stitch through the reciprocating lift sewing stroke through a stitch to be sewn and forming a fixed stitch with the lower hook for the reciprocating weave stroke a sewn web of the object to be sewn and an interlacing coil formed by each of the stitches and the bottom stitch and connected to the sewn web, the dial cutter is characterized by: the dial cutter a first blade portion, a second blade portion disposed adjacent to the first blade portion and protruding away from the stylus, and a dial portion extending from a side of the second blade portion away from the first blade portion Wherein the dial cutter is driven to have a direction toward the interlaced coil a reciprocating secant stroke, and the dial cutter has a threading state in which the interlacing coil is opened in the direction of the interlacing coil and protrudes through the interlacing coil, and a direction of the fixed cutter is advanced to the dialing The wire portion pulls each of the burr sutures and the bottom blade is pulled by the first blade portion, and the second blade portion and the first blade portion are respectively matched with the fixed cutter to cut each of the burs The suture and the bottom suture form a tangential state with respect to the sewn web and a tangent line connecting the end line segments of the margin line. The thread cutting cutter of the sewing machine of claim 1, wherein the first blade portion includes a bottom thread in the threading state and a displacement of each of the needle stitches to the first blade portion. a first guiding surface between the second cutting edges. The thread cutting cutter of the sewing machine according to claim 1 or 2, wherein the second blade portion includes a guide thread for guiding each of the needle stitches between the second blade portion and the dial portion in the threading state The second guiding surface. The thread cutting cutter of the sewing machine according to claim 1 or 2, wherein the dialing portion includes a direction facing the second blade portion and guiding each of the needle stitches to the dialing line in the threading state a guiding surface away from the side of the second blade portion, and a connecting guiding surface disposed on a side of the dialing portion away from the second blade portion and pulling each of the bur stitches in the tangential state Hook the line. The thread cutting cutter of the sewing machine according to claim 3, wherein the dialing portion includes a direction facing the second blade portion and guiding each of the stylus stitches to the dialing portion in the threading state. a guiding surface on one side of the second cutting edge portion, and a connecting guiding surface disposed on a side of the dialing portion away from the second cutting edge portion and pulling each of the burr stitches in the tangential state to form the end The hook surface of the line segment. The thread cutting cutter of the sewing machine according to claim 1 or 2, wherein the dial portion extends away from the second blade portion and forms an acute angle of less than 90 degrees with respect to the dial cutter. The dial cutter of the sewing machine of claim 4, wherein the dial portion extends away from the second blade portion and forms an acute angle of less than 90 degrees with respect to the dial cutter. The thread cutting cutter of the sewing machine according to claim 5, wherein the dial portion extends away from the second blade portion and forms an acute angle of less than 90 degrees with respect to the dial cutter. The utility model relates to a method for generating an end line segment after cutting a line by using a dial cutter, which is applied to a sewing machine, the sewing machine has a plurality of needles for respectively pulling a needle stitch and performing a reciprocating lifting sewing stroke, and a pair of needles should be used. a lower hook for setting and pulling a bottom stitch to perform a reciprocating threading stroke toward the thimbles, and a lower hook needle disposed away from the side of the bur and engaging with the dial cutter to cut each The sewing thread and the fixed cutter of the bottom stitch, each of the needles pulling each stitch of the needle through a reciprocating lifting stitch to pass through a sewing object and performing the same with the lower hook The bottom stitch drawn by the reciprocating weave stroke forms a sewn web that fixes the object to be sewn and an interlacing coil formed by each of the stitches and the bottom stitch coils and connected to the sewn web. The method for generating the end line segment after the tangential cutting by using the dial cutter comprises the following steps: Step 1: using the dial cutter to perform a reciprocating secant stroke toward the interlacing coil and sequentially using the first line on the dial cutter a blade guides the bottom stitch and each of the burs a second cutting edge portion of the thread cutting cutter and a dial portion spaced apart from the second cutting edge portion to guide each of the needle stitches so that the bottom stitch line is located at the first cutting edge portion Between the second blade portions, and each of the locating stitches is located on a side of the dial portion away from the second blade portion; and step 2: driving the wire cutter to the fixed cutter direction Reciprocating the tangential stroke, and pulling the bottom seam line by the first cutting edge portion, and pulling each of the burr sutures by using the plucking portion, and then sequentially fixing the second cutting edge portion and the first cutting edge portion with the fixing The cutters are interlaced, and each of the burr sutures and the bottom sutures are cut to form a margin line segment and an end line segment connecting the margin line segments. The method for generating an end line segment by using a dial cutter according to claim 9, wherein the step 1 further comprises guiding a displacement of each of the locile stitches to the dial by using a guiding surface of the dialing portion. a sub-step between the line portion and the fixed cutter, and the second step further includes a sub-step of pulling each of the bur stitches with a hook surface of the dial portion.