JPH0910461A - Embroidery sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a point tool from failing to capture a needle thread by allowing a sewing needle to escape from the point tool due to the pulling of the sewing needle by a worked fabric. SOLUTION: A slant face 42 forming a descending gradient toward the tip part 3 of a sewing needle 2 inserted from the upper part of a peripheral edge on the opposite side to a peripheral edge located on a point tool 16 side to the sewing needle 2 inserted through a needle pitfall 40, is provided on said peripheral edge on the opposite side, of the peripheral edge forming the needle pitfall 40. Consequently the sewing needle 2, escaping from the point tool 16, descends, maintaining its tip part 3 to be in contact with the slant face 42, and is guided to a home position before the slippage of the needle 2. Thus it is possible to prevent the point tool from failing to capture a needle thread 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pattern sewing machine.

[0002]

2. Description of the Related Art Conventionally, as a pattern sewing machine, a sewing needle that forms a stitch by cooperation with a full-rotation rotary hook to pattern-sew a workpiece, a motor that drives the sewing needle up and down, and a sewing target. 2. Description of the Related Art A pattern sewing machine including a feeding device that feeds an object in a predetermined direction is known. The full rotary hook has an inner hook for rotatably containing a bobbin around which a bobbin thread is wound in the winding direction and an outer hook for rotatably holding a sword tip for catching the upper thread along the outer circumference of the inner hook. And are provided. FIG. 6 is a partial cross-sectional explanatory view of the vicinity of a sword tip provided on the full rotation rotary hook. As shown in the figure, a needle drop hole 206 through which the sewing needle 2 is inserted and a hook stopper member (not shown) for stopping the rotation of the inner hook 202 are provided in the vicinity of the rotation locus of the sword tip 200 for catching the needle thread loop 6. ) Can be engaged. Then, the sewing needle 2 moves up and down in the vicinity of the sword tip 200 to cause the sword tip 200 to capture the upper thread loop 6.

[0003]

By the way, in FIG. 6, the sewing needle 2 is pulled in the direction of the arrow Y1, and the sword tip 2
When the gap distance X1 between 00 and the sewing needle 2 becomes large, the sword tip 200 cannot catch the upper thread loop 6, resulting in skipping and thread breakage. Such a situation is likely to occur in the pattern sewing machine in which the feeding direction of the work cloth constantly changes. In addition, when a thick work cloth is sewn, it is difficult for the sewing needle to come off from the work cloth and the sewing needle is easily pulled by the work cloth.

Therefore, conventionally, as shown by an imaginary line in FIG. 2 for explaining the full rotary hook provided in the pattern sewing machine of the present invention, it is below the needle plate 100 and in the vicinity of the insertion path of the sewing needle 2. A needle guide 102 or a needle hole 104 of the needle plate 100 which is eccentric from the center of the sewing machine needle 2.
By adopting the above method, the sewing needle 2 is prevented from escaping from the vicinity of the sword tip 16. However, in these methods, the needle thread causes the needle guide 102 and the needle hole 106 to move.
There is a problem that thread tightness is deteriorated because the needle thread is slidably contacted with the upper thread to give resistance to the upper thread.

Therefore, an object of the present invention is to realize a pattern sewing machine in which a sewing needle does not separate from a sword tip for catching the upper thread without giving a resistance to the upper thread.

[0006]

In order to achieve the above object, the present invention provides an inner hook for accommodating a bobbin wound with a lower thread rotatably in the winding direction, and a sword tip for catching the upper thread. It consists of an outer hook that is rotatable along the outer circumference of the inner hook, and a needle drop hole through which a sewing needle is inserted near the rotation locus of the sword tip of the inner hook, and rotation of the inner hook is stopped. A full-rotation rotary hook provided with an engaging recess capable of engaging the hook-stop member, a sewing needle for forming a stitch by the cooperation of the full-rotation rotary hook and pattern-stitching a workpiece, and this sewing needle In a pattern sewing machine provided with a motor for driving up and down, and a feeding device for feeding the material to be sewn in a predetermined direction, in the full rotary hook, among the peripheral edges forming the needle drop hole, With respect to the sewing needle inserted through the needle drop hole, it is opposite to the peripheral edge located on the side of the sword. The periphery of the side, from the top of the periphery,
A technical means is employed in which an inclined surface having a downward slope is provided toward the tip of the inserted sewing needle.

[0007]

According to the present invention, in the full-rotation rotary hook, one of the peripheral edges forming the needle drop hole is opposite to the peripheral edge located on the sword tip side with respect to the sewing needle inserted in the needle drop hole. Since a slanted surface having a downward slope is provided on the peripheral edge of the sewing machine from the upper part of the peripheral edge toward the tip of the inserted sewing needle, the sewing needle is pulled in the direction in which it escapes from the tip of the sword by the material to be sewn. Even if the insertion path to the needle drop hole is displaced in the peripheral direction on the opposite side, the displacement is caused while the tip of the sewing needle is brought into contact with the inclined surface formed on the peripheral edge on the opposite side. You can guide to the previous position and correct the deviation. Therefore, when the sewing needle escapes from the tip of the sword,
It is possible to prevent the sword tip from failing to catch the upper thread and causing skipping or thread breakage. Moreover, there is no need to decenter the needle hole or provide a needle guide unlike the conventional case,
Since there is no portion where the upper thread is in sliding contact, deterioration of thread tightness can be prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the pattern sewing machine of the present invention will be described with reference to FIGS. First, the main structure of the pattern sewing machine of the present embodiment will be described with reference to FIG. 1 which is an external perspective view thereof. There is a machine base 5 on the pattern sewing machine 1.
0 is provided, and the sewing machine main body 5 is mounted on the machine base 50.
2 are installed. The sewing machine main body 52 is provided with a needle bar 54 to which the sewing needle 2 is attached, and the needle bar 54 is vertically driven by a sewing machine motor and a main shaft (not shown).

The first guide rail 5 in the Y-axis direction is provided on the left and right supports 56, 56 which are integrated with the machine base 50 and face each other.
8 are fixed to each of the first guide rails 58.
The first racks 60 are fixed in the longitudinal direction of. A support member 62 is provided on each of the first racks 60, 60.
On top of 62 is a moving frame 64 and a second rack 66.
Are movably supported in the Y-axis direction. And the first
The motor 68 rotationally drives a pinion (not shown) meshing with the first rack 60 via the shaft 70, whereby the moving frame 64 reciprocates in the Y-axis direction.

A supporting member 80 is provided on the second rack 66, and the moving frame 6 is attached to the supporting member 80.
A carriage 84 guided and supported on the carriage 4 is attached. A spline shaft 74 is inserted through the support member 80, and the spline shaft 74 is engaged with a spline bearing 82. Further, both ends of the spline shaft 74 are rotatably supported in the Y-axis direction by supports 72, 72, and the spline shaft 74 is rotationally driven by a second motor 76 via a gear 78. The rotation of the spline shaft 74 causes the carriage 84 to reciprocate on the moving frame 64 in the X-axis direction.

A clamp member 86 and a clamp cylinder 88 are attached to the carriage 84, and a pallet 90 is fixed to the clamp member 86. The work cloth 4, which is a material to be sewn, is stretched around the pallet 90.
The pattern sewing machine 1 configured as described above rotates the first motor 68 and the second motor 76 to freely move the work cloth 4 in the XY plane immediately below the sewing needle 2 and perform the pattern sewing. Sew.

Next, the structure of the full rotary hook provided in the pattern sewing machine 1 will be described with reference to FIGS. 2 to 5. 2 is a perspective view showing the full-rotation rotary hook, FIG. 3 is a plan view of the inner hook, and FIG. 4 is a vertical sectional view of the full-rotation rotary hook. As shown in FIG. 2, the boss portion 14 of the outer hook 12 is fixed to the hook shaft 10, and the outer hook 12 is rotationally driven integrally with the hook shaft 10.
The outer hook 12 is provided with a sword tip 16 for capturing the upper thread loop 6 and a cam plate 18 for guiding the captured upper thread loop 6.

Further, as shown in FIG. 4, a rail groove 22 for rotatably guiding the inner hook 20 is provided on the cylindrical inner peripheral wall surface of the outer hook 12.
As shown in FIG. 3, a rail 24 that engages with the rail groove 22 is provided on the cylindrical outer periphery of the inner hook 20. A stud holding shaft 26 is provided at the center of the inner hook 20, and a bobbin 28 around which the lower thread 8 is wound is axially fixed to the stud holding shaft 26 so as to be rotatable in the winding direction. . The bobbin 28 is held by a bobbin case 30.

The stud holding shaft 26, the bobbin case 30, and the bobbin 28 at the center of the hook shaft 10, the outer hook 12, and the inner hook 12 have a common central axis line. An engagement recess 32 is formed in the upper end portion of the inner hook 20.
As shown in FIG. 3, a hook stopper member 34 for stopping the rotation of the inner hook 20 is provided.
The protrusions 36 are engageable. Further, as shown in FIGS. 3 and 4, a needle drop hole 40 having a substantially oval shape, through which the needle tip of the sewing needle 2 is inserted, is provided at the center of the upper portion of the side wall of the inner hook 20.

Now, the structure of the needle drop hole 40 will be described with reference to FIGS. 3 and 5. FIG. 5 is a partially enlarged sectional view of the needle drop hole 40. Of the peripheral edges forming the needle drop hole 40, a peripheral edge 44 opposite to the peripheral edge 43 located on the sword tip 16 side with respect to the sewing needle 2 inserted in the needle drop hole 40.
Further, an inclined surface 42 having a downward slope from the upper part of the peripheral edge 44 toward the tip 3 of the inserted sewing needle 2 is provided.

By the way, when the work cloth 4 is pattern-sewn or the thick work cloth 4 is sewn, the sewing needle 2 is pulled by the work cloth 4, and the work cloth 4 travels, that is, the tip of the outer hook 12. 1
The sewing needle 2 tries to bend in the direction away from 6 (the direction indicated by the arrow Y1 in FIG. 6). If this is left unattended 16
The gap distance X1 between the sewing needle 2 and the sewing needle 2 becomes excessive. That is, since the insertion path of the sewing needle 2 into the needle drop hole 40 is displaced toward the opposite peripheral edge 44, it becomes difficult for the sword tip 16 to catch the loop of the upper thread 6. The gap distance X1 is 0 to 0.1 m
If the size of m is appropriate and the gap distance X1 is larger than this, the probability of catching failure such as skipped stitches or single thread catching increases.

However, even if the insertion path of the sewing needle 2 into the needle drop hole 40 is deviated in the direction of the peripheral edge 44 on the opposite side, the inclined surface 42 is formed in the descending direction of the sewing needle 2. Since the sewing needle 2 is provided, the tip portion 3 of the sewing needle 2 descends while contacting the inclined surface 42, is guided to the position before the shift, and the deviation is corrected. Therefore, the gap distance X1 between the sword tip 16 and the sewing needle 2 does not become excessive, so that the sword tip 1
2 makes it easier to catch the loop of the upper thread 6, and the tip of the sword 1
The capture failure of 6 is prevented, and stable capture is possible. Further, the slanted surface 42 is slidably contacted only with the tip portion 3 of the sewing needle 2 and does not contact the upper thread 6 or the lower thread 8 at all, so that the upper thread 6 and the lower thread 8 can be smoothly delivered. It is possible to perform pattern sewing with tight thread tightness.

[0018]

As described above, according to the present invention, it is possible to realize a pattern sewing machine in which the sewing needle is not separated from the sword tip for catching the upper thread without giving resistance to the upper thread.

[Brief description of the drawings]

FIG. 1 is an external perspective view showing the main configuration of a pattern sewing machine according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a full rotary hook.

FIG. 3 is a plan view of an inner pot.

FIG. 4 is a vertical sectional view of a full rotary hook.

5 is a partially enlarged sectional view of a needle drop hole 40. FIG.

FIG. 6 is a partial cross-sectional explanatory view in the vicinity of a sword tip of a full-rotation rotary hook provided in a conventional pattern sewing machine.

[Explanation of symbols]

 1 Pattern sewing machine 2 Sewing needle 3 Tip part 4 Work cloth 12 Outer hook 16 Sword tip 20 Inner hook 40 Needle drop hole 42 Inclined surface 43 Peripheral edge 44 Peripheral edge 50 Machine base 52 Sewing machine main body 58 First guide rail 60 First rack 64 Moving frame 66 Second rack 68 First motor 70 Shaft 74 Spline shaft 76 Second motor 84 Carriage 86 Clamping member 90 Pallet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Minoru Yamaguchi Inventor Minoru 15-1, Naeshiro-cho, Mizuho-ku, Nagoya City Brother Industries, Ltd.

Claims (1)

[Claims] 1. An inner hook for rotatably housing a bobbin wound with a lower thread in the winding direction, and an outer hook for rotatably holding a sword tip for catching an upper thread along the outer circumference of the inner hook. And in the vicinity of the rotation trajectory of the sword tip of the inner hook,
A full rotary hook provided with a needle drop hole through which a sewing needle is inserted and an engaging recess capable of engaging the rotary hook stopping member for stopping the rotation of the inner rotary hook, and the full rotary hook by cooperation of the full rotary hook. In a pattern sewing machine, a sewing needle for forming stitches for pattern stitching a sewing object, a motor for driving the sewing needle up and down, and a feeding device for feeding the sewing object in a predetermined direction, wherein: The full-rotation rotary hook includes a peripheral edge forming the needle drop hole, a peripheral edge opposite to the peripheral edge located on the sword tip side with respect to the sewing needle inserted through the needle drop hole, and from the upper part of the peripheral edge. The pattern sewing machine characterized in that an inclined surface having a downward slope is provided toward a tip portion of the inserted sewing needle.