JPH0664Y2 - Thread shifting device for sewing machine with buttons - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] This invention provides a shank button or a marble button having a button hole penetrating along the back surface of the button body, such as a gold button for student wear. A sewing machine used to sew various kinds of sewn products. Specifically, the lower end loop portion of the sewing thread inserted below the material is sewn with a looper to form a stitch by vertically reciprocating sewing needles. The present invention relates to a thread pulling device for a button sewing machine configured as described above.

[Prior Art] FIG. 6 is a front view of an essential part of a conventional button sewing machine of this type, and FIG. 7 is a side view of the essential part. In FIG. 6, 1 is a sewing needle, and 1 is the sewing needle. As shown by the imaginary line in the figure, it reciprocates up and down along a fixed path H. A fabric guide 2 guides the lateral movement of the fabric 3 by causing the sewing portion 3A of the fabric 3 to project in the vertical movement path H of the sewing needle 1. Reference numeral 4 denotes a looper, which when the sewing needle 1 reaches the bottom dead center,
By approaching the outer surface of the sewing needle 1 and rotating in the direction of arrow a at a timing such that A becomes the center of the sewing needle 1, the material 3
Take out the lower end loop portion 5A of the sewing thread 5 brought in below. 6 is a thread pulling tool, and the thread pulling tool 6 is bent almost in a sickle shape as a whole, and the tip thereof is shown in FIG.
As shown in the enlarged view in (A) and (B), the planar shape is almost V
The deepest ridgeline 6B in the shape of a letter is the vertical movement path H of the sewing needle 1.
A thread pulling portion 6A which is parallel to the thread pulling tool 6 is formed, and more specifically, when the tip portion 1A of the sewing needle 1 is flush with the upper surface of the thread pulling tool 6 immediately before reaching the bottom dead center. , By rotating in the direction of the arrow b, the middle part of the two sewing threads 5B and 5C laid between the sewing portion 3A of the material 3 and the looper 4 and the sewing needle 1 is moved by the thread shifting portion 6A. The sewing needles 1 are collected and retracted from the vertical movement path H of the sewing needle 1.

Reference numeral 7 is a needle receiver, which is provided at a position facing the thread shifting tool 6 across the vertical movement path H of the sewing needle 1. The needle receiver 7 has one end fixed to the frame 8 and extends laterally and upward. The needle receiver inclined toward the lower end of the upper end of the needle receiver 7 is closer to the vertical movement path H of the sewing needle 1. The surface 7A is formed. This inclined needle receiving surface 7A
The clearance t between the needle and the outer surface of the sewing needle 1 is about 0.2 to 0.3 mm, and when the tip portion 1A of the sewing needle 1 is bent forward and descends, the tip of the sewing needle 1 is moved by the inclined needle receiving surface 7A. The portion 1A is configured to slide down and guide to the vertical movement path H side.

According to the sewing machine having the above-described structure, when the sewing needle 1 descends toward the looper 4, the two sewing threads 5 that are suspended between the sewing portion 3A of the material 3 and the looper 4 and the sewing needle 1 are used.
Intermediate portions of B and 5C are gathered together by the yarn pulling portion 6A of the yarn pulling tool 6 and retracted from the vertical movement path H of the sewing needle 1,
The sewing needle 1 moves downward through the side portion of the retracted gathering thread portion. When the tip portion 1A of the sewing needle 1 descends forward in a bent state, it is slid down and guided to the predetermined vertical movement path H side by the inclined needle receiving surface 7A.
As a result, the lower end loop portion 5A of the sewing thread 5 brought under the cloth 3 is reliably picked up by the tip end portion 4A of the looper 4, and the sewing is performed as specified.

[Problems to be Solved by the Invention] According to the thread shifting device of the conventional button sewing machine configured as described above, unlike the case where the flat button is sewn, like the shank button and the marble button, Since the button having the button hole on the back side is to be sewn, there is the following problem.

That is, in this type of sewing machine, the button to be sewn has a button hole on its back surface, such as a shank button or a marble button, and the button hole has various shapes and sizes. In order to enable many kinds of buttons to be sewn with one sewing machine, this kind of sewing machine has a needle plate having a needle drop hole for restricting the movement range of the needle attached to the material guide. Not not. Therefore, as in the above-described conventional thread pulling tool, the ridgeline 6B of the deepest portion 1A of the substantially V-shaped thread pulling portion is formed parallel to the vertical movement path H of the sewing needle 1. , There is a high possibility that the sewing needle 1 will fall between the two threads 5B and 5C that were previously brought together and collected by the thread shifting tool.
As a result, there is a problem in that the predetermined stitches cannot be formed stably.

The present invention has been made in view of the above circumstances, and a sewing machine with a button that can perform a proper stitching performance and surely and stably form a predetermined stitch by merely making a very simple structural improvement. An object of the present invention is to provide a yarn pulling device.

[Means for Solving the Problems] In order to achieve the above object, the thread shifting device of the button sewing machine according to the present invention is provided with a middle of two sewing thread portions which are suspended between the cloth, the looper and the sewing needle. The V-shaped thread pulling portion formed at the tip of the thread pulling tool that moves so that the portions are gathered together and retracted from the vertical movement path of the sewing needle, and the ridge line at the deepest portion is the vertical movement path of the sewing needle. It is characterized in that it is formed so as to be inclined with respect to it.

[Operation] According to the present invention, when the sewing needle descends, the middle part of the two sewing threads which are brought in first and are passed between the cloth and the looper and between the looper and the sewing needle is moved. By gathering along the inclined ridgeline of the V-shaped thread pulling portion in the tool, the two thread portions are retracted from the vertical movement path of the sewing needle with a little spread above it, and the sewing needle is It can be prevented from falling between the two gathering yarn portions. As a result, the suture thread previously brought in and the suture thread brought in next overlap with each other in the front-rear direction, so that the predetermined sewing can be performed normally and reliably.

[Embodiment of the Invention] An embodiment of the invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of an essential part of a sewing machine with buttons according to an embodiment of the present invention. In FIG. 1, reference numeral 1 is a sewing needle, and the sewing needle 1 is a lifting drive mechanism (not shown) provided in a sewing machine arm 11. And reciprocates up and down the fixed path H via the above. Reference numeral 2 denotes a cloth guide, which guides the folded cloth 3 to move laterally in the horizontal direction along a horizontal plane, and is formed in a strip plate shape having a constant width in the front and back and has a needle drop hole. It does not have a needle plate. Reference numeral 14 denotes a button holder, which is a pair of left and right arc-shaped gripping pieces that sandwich the shank button 9 from both sides of the button periphery in a standing posture in which a button hole 9b of a shank portion 9a provided on the back surface of the shank button 9 penetrates vertically.
The button holder 14 is provided with A and 14B, and is maintained in a fixed posture so as to hold the shank button 9 in the standing posture described above both when rooting and when winding the root.

Reference numeral 10 is a material holder, which is formed by folding the material 3 for sewing the shank button 9 in half and inserting it in the middle of the folded material 3 so that the button sewing point of the material 3 is close to the vertical movement path H of the sewing needle 1. Let it be fixed. A dough holder rotating cylinder 20 is configured such that the dough holder 10 can be switched between a fixed state and a released state with respect to the dough 3 by contraction and extension of the cylinder 20.

12 is a material presser, 13 is a material presser operating cylinder, and this material presser 12 is brought into contact with the upper surface of the double-folded material 3 placed on the material guide 2 by the material holder 10 obliquely from above, and the material 3 is held. The material 3 can be prevented from bending by being able to press it forward.

Reference numeral 15 denotes a movable table. The movable table 15 is configured to reciprocate in two-dimensional directions orthogonal to each other in a horizontal plane, that is, the XY axis directions, via two stepping motors and timing belts (not shown). There is. A pair of left and right cloth holder arms 16 and 17 are fixed to the left and right side surfaces of the movable table 15. By fixing and connecting the material guide 2 across the pair of material holder arms 16 and 17, the button holder 1
4 and the cloth holder 10 are configured to be reciprocally movable in the X-Y axis directions via the movable table 15.

Reference numeral 18 is a button retainer, and 19 is a button retainer actuating cylinder, which comes into contact with the central portion of the surface of the shank button 9 held by the button holder 14 by the extension operation of the cylinder 19 at the time of button sewing. The entire button holder 14 is fixed to the cloth guide 2 in a predetermined posture.

In the button-attached sewing machine having the above-described structure, below the material guide 2, as in the conventional example shown in FIG.
A looper 4, a yarn pulling tool 6, and a fixed needle receiving tool 7 are provided, and the configuration of each of these parts is the same as the conventional one except for the points described below, so a detailed description will be given here. It will be omitted and only the differences will be described.

FIG. 2 is a side view of the main part. In FIG. 2, 6B is the deepest ridgeline of the V-shaped thread pulling portion 6A in the thread pulling tool 6, and this ridgeline 6B is shown in FIG. 3 and FIG. As clearly shown, the sewing machine 1 is formed so as to be inclined with respect to the up-and-down movement path H of the sewing needle 1 such that the sewing needle 1 is separated further downward. Reference numeral 21 denotes an inclined needle receiving surface, and the needle receiving surface 21 is an inclined surface that is closer to the vertical movement path H of the sewing needle 1 toward the side edge portion near the thread pulling portion 6A at the tip of the thread pulling tool 6. It is formed, and is formed slightly above the needle receiving surface 7A of the fixed needle receiving tool 7 described above, and is formed in a reverse inclined surface with respect to the needle receiving surface 7A.

Next, the operation of the above configuration will be described.

As shown in FIG. 1, a pair of holding pieces 1 of the button holder 14
4A and 14B hold the shank button 9 from both sides of its circumference, and then operate the button retainer 18,
The tip of the shank button 9 is brought into contact with the center of the front surface of the shank button 9 and is forcibly pressed against the back surface of the fabric guide 2 including the button holder 14, thereby defining the setting posture of the shank button 9 with respect to the button holder 14. With
Both the button 9 and the holder 14 are fixed and held in a predetermined button attachment posture without looseness of the button holder 14.

In parallel with this, the dough 3 is folded in two and set in the dough holder 10. Next, the cylinder 20 is extended by depressing a pedal (not shown), and the cloth holder 10
Is fixed to the upper surface of the cloth guide 2 together with the half-folded cloth 3 and the cylinder 13 is extended so that the cloth presser 12 presses the upper surface of the half-folded cloth 3 from above to prevent the cloth 3 from bending.

In this state, if the button switch (not shown) is turned on,
Under operation control by a microcomputer (not shown), the movable table 15 is reciprocally driven and moved in the X-axis direction and the Y-axis direction, and rooting and a series of buttoning of root winding are performed.

In the button attaching operation as described above, the thread pulling tool 6
Works as follows.

That is, in FIG. 5 (A), the sewing needle 1 passes through the button hole 9b of the shank button 9 and the cloth 3, the lower end loop portion of the sewing thread is picked up by the looper 4, and the sewing needle 1 reaches the top dead center. State, and in this state, two sewing threads 5B,
5C is between the cloth 3 and the looper 4 and between the looper 4 and the sewing needle 1
It has been handed over between. Next, the sewing needle 1 is button 9
Outside the button hole 9b of the sewing machine, the cloth 3 passes through the cloth 3 and descends toward the looper 4, and the tip portion 1A of the sewing needle 1 moves to the thread pulling tool 6
When the thread pulling tool 6 rotates in the direction of the arrow b at the timing when the thread pulling tool 6 is flush with the upper surface of the sewing machine, the thread pulling section 6A at the tip of the thread pulls the two sewing threads 5B and 5C and the thread pulling section 6A. Collect on the ridgeline 6B side of the deepest part. At this time, since the deepest ridgeline 6B is inclined, the two gathered sewing threads 5B and 5C are, as shown in FIG. 5 (B),
The sewing needle 1 is retracted to the side of the vertical movement path H in a posture inclined with respect to the vertical movement path H. Therefore, it is ensured that the upper portions of the two sewing threads 5B and 5C are in close contact with each other and are displaced to the front side of the vertical movement path H of the sewing needle 1 and the sewing needle 1 falls between the two sewing threads 5B and 5C. To be prevented. Further, even when the sewing needle 1 reaches the bottom dead center, the thread shifting tool 6 is in the same thread shifting action state as shown in FIG. Since the lower end loop portion 5A of the above is surely picked up by the looper 4, it is possible to surely perform the predetermined sewing.

In addition, in the buttoning operation, when the tip portion 1A of the needle 1 descends in a state of being bent forward, the tip portion 1A of the sewing needle 1 is guided by the inclined needle receiving surface 7A of the fixed needle holder 7. Guides the needle 1 by sliding it down into a predetermined vertical movement path H while straightening it backward.
When A descends in a state of being bent backward, it is guided by the inclined needle receiving surface 21 formed near the tip of the thread pulling tool 6 and straightens the tip portion 1A of the sewing needle 1 to the front side. While being able to slide down and guide in a predetermined vertical movement path H, not only damage and deformation of the sewing needle 1 and the thread pulling tool 6 etc. can be prevented, but also the removal of the thread by the looper 4 can be made more reliable. it can.

Further, although the case where the shank button is used as the application target button has been described in the above embodiment, the same effect as described above can be obtained when the shank button is used for sewing the marble button.

[Effects of the Invention] As described above, according to this invention, the midpoints of the two sewing threads that are previously brought under the material are gathered together at one point, and the vertical movement of the sewing needle that carries the thread next is brought together. Since it can be retracted in a posture tilted with respect to the route, not only the gathering point but also the two thread portions above the gathering point are not widened, but the needle is moved up and down in close contact with each other. It is possible to exert an appropriate yarn pulling performance such as displacing the yarn in the front-back direction with respect to the route. Therefore, even though this type of button sewing machine does not have a needle plate with needle drop holes, it often changes back and forth the drop position of the sewing needle that brings in the next thread according to the type of button. , The sewing needle can be prevented from falling between the two previously brought in sewing threads, and predetermined sewing can be performed stably. That is, it is possible to attach the button reliably and stably.

In particular, when the two gathered thread portions are configured to be retracted to the rear side, the looper can surely remove the sewing thread, and the sewing can be further stabilized.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part of a button sewing machine showing an embodiment of the present invention, FIG. 2 is a side view of the essential part, FIG. 3 is an enlarged plan view of the essential part, and FIG. 4 is FIG. IV-IV line side view of
5 (A), (B), and (C) are enlarged perspective views of a main part for explaining the thread shifting operation, and FIG. 6 is a front view of the main part common to the present invention and the conventional example, and FIG. FIG. 8 is a side view of the main part of the conventional example, and FIGS. 8A and 8B are an enlarged plan view and a side view of the main part of the conventional example. 1 ... Sewing needle, 2 ... Fabric guide, 3 ... Fabric, 4 ... Looper,
5, 5B, 5C ... Sewing thread, 6 ... Thread shifting tool, 6A ... V-shaped thread shifting section, 6B ... Deepest ridge line of the thread shifting section, 7 ... Needle receiving tool, 9 ... Shank button, 10 ... Fabric holder , 14 ...
Button holder, 15 ... Movable table, H ... Vertical movement path of sewing needle.

Claims (2)

[Scope of utility model registration request] 1. A sewing needle which reciprocates up and down along a certain path, a cloth guide which guides lateral movement of a bi-folded cloth along a horizontal plane, and a button of the cloth which is inserted in the middle of the bi-folded cloth. A material holder for fixing and holding the sewn portion close to the vertical movement path of the sewing needle, a button holder for holding the button in a posture in which the button hole on the back side is vertically penetrated facing the material holder, and this button A drive device for reciprocating the holder and the material holder in two-dimensional directions orthogonal to each other with respect to the vertical movement path of the sewing needle, and a looper for picking up the lower end loop portion of the sewing thread when the sewing needle reaches the bottom dead center. Immediately before the sewing needle reaches the bottom dead center, the intermediate portions of the two sewing threads that have been laid between the cloth, the looper and the sewing needle are gathered together to bring up and down the movement of the sewing needle. In a button-attached sewing machine including a thread pulling tool that moves so as to retract from the thread pulling tool, a V-shaped thread pulling section formed at a tip end of the thread pulling tool has a deepest ridge line for vertical movement of the sewing needle. A thread shifting device for a button sewing machine, which is formed so as to be inclined with respect to a route. 2. The thread pulling tool rotates in a direction in which two sewing thread portions gathered in a V-shaped thread pulling portion at the tip end thereof are retracted rearward with respect to the vertical movement path of the sewing needle. The thread shifting device for the button sewing machine according to claim 1, wherein the thread shifting device is configured as described above.