JPH08309066A - Clockwise full rotation vertical shuttle - Google Patents

Abstract

PURPOSE: To prevent the generation of thread breakage and needle breakage at the time of starting sewing and at the time of performing idle sewing by forming an extended projection part for covering a clearance between an outer peripheral part and a back plate extended along the edge of the outer peripheral part following a projection part formed on the back plate for covering the clearance between the sword tip rear part of a rotating hook and the back plate. CONSTITUTION: On the surface of the back plate 4, the extended projection part 4a' is formed following the projection part 4a for covering the clearance between the sword tip rear part 1b of the rotating fook 1 and the back plate 4. The extended projection part 4a' is extended along the edge of the outer peripheral part 1c following the sword tip rear part 1b of the rotating hook 1 and covers the clearance generated between the outer peripheral part 1c and the back plate 4. In this clockwise full rotation vertical shuttle constituted in such a manner, even when needle thread 6 is slackened at the time of starting the sewing and at the time of performing the idle sewing, etc., the needle thread 6 is obstructed by the extended projection part 4a', does not advance to the clearance between the outer peripheral part 1c following the sword tip rear part of the rotating hook 1 and the back plate 4 and is not held in the clearance and cut off. Also, the needle thread 6 is prevented from being detached to the attaching shaft direction of the rotating hook 1 indicated by an arrow.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clockwise full-rotation vertical shuttle (hereinafter referred to as a DP type shuttle) used in an industrial sewing machine.

[0002]

2. Description of the Related Art As shown in FIG. 1, a DP type shuttle has an outer hook 1 which rotates fully clockwise, a non-rotating inner hook 2 in which a bobbin case 5 is set, and an outer hook 1 which is fixed to the outer hook 1. The inner hook 2 for sandwiching and supporting the inner hook 2 with the outer hook 1, and the outer hook 1
It is composed of a back plate 4 fixed to. Outer pot 1 of this pot
Has the shape shown in FIG. 2, and the back plate 4 has the shape shown in FIG. Then, on the front side of the back plate 4, a protrusion 4a is formed.
Are formed. This protruding portion 4a, when assembled,
The rear portion 1b and the back plate 4 of the outer hook 1 in the rotational direction of the sword tip 1a
It covers the gap between and.

In this hook, when the needle sticks into the cloth and the needle thread loop formed during the upward pulling out is caught by the sword tip 1a of the outer hook 1 and makes a full turn, the needle thread loop goes around the hook, The needle thread is entangled with the lower thread to form a seam.

FIGS. 4 (1) and 4 (2) show a state in which the sword tip 1a has captured the needle thread loop 6 in the stitch forming process. As can be seen from these figures, the needle thread (upper thread) 6 is normally guided by the protruding portion 4a of the back plate 4 so as not to be sandwiched between the rear portion 1b in the rotational direction of the sword tip 1a and the back plate 4.

[0005]

However, when one of the upper threads 6 is not held by the cloth at the start of sewing or when empty stitching, the upper thread 6 is exposed after the sword tip 1a catches the needle thread loop 6. As shown in FIG. 4C, the upper thread 6 is slackened. When the amount of slack becomes extremely large, the upper thread 6 reaches the outer peripheral position of the back plate 4, and as a result, the gap between the outer plate 1c following the sword tip rear part 1b of the outer hook 1 and the back plate 4 is increased. It may be caught in the box or may come off in the axial direction of the hook attachment indicated by the arrow B and cut. In particular, the needle may break if the upper thread has a large strength.

It is an object of the present invention to prevent thread breakage or needle breakage from occurring at the start of sewing or empty stitching in a clockwise full rotation vertical hook.

[0007]

In order to achieve the above object, the clockwise full-rotation vertical hook of the present invention is provided on a back plate that covers a gap between the back portion of the outer hook and the back plate. Following the protruding portion, the back plate is provided with an extended protruding portion that extends along the edge of the outer peripheral portion of the outer hook following the sword tip rear portion and covers the gap between the outer peripheral portion and the back plate. .

[0008]

In the clockwise full-rotation vertical hook constructed as described above, even if the upper thread sags at the start of sewing or empty stitching, the upper thread is squeezed into the extension protrusion and It does not go into the gap between the outer peripheral part and the back plate, and does not come off in the hook axis direction.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a clockwise full-rotation vertical hook according to the present invention will be described with reference to FIGS.

This clockwise full-rotation vertical hook is basically the same as the conventional clockwise full-rotation vertical hook, and is a non-rotating inner hook in which the bobbin case 5 is set and the outer hook 1 which rotates fully clockwise. It is composed of a hook 2 and an inner hook presser 3 fixed to the outer hook 1 so as to sandwich and support the inner hook 2 between the outer hook 1 and the outer hook 1, and a back plate 4 fixed to the outer hook 1.

As shown in FIGS. 6 (1) and 6 (2), the outer hook 1 has an outer peripheral portion 1c following the rear portion 1b in the rotational direction of the sword tip 1a for catching the needle thread loop 6.

As shown in FIGS. 5 (1), (2) and (3), the back plate 4 has a needle receiver 4 for preventing the needle from moving to the sword tip 1a side.
It has b and has a role of preventing the thread from escaping to the back side of the hook when the sword tip 1a catches the needle thread loop 6.

On the surface of the back plate 4 used in this embodiment,
As shown in FIG. 5, an extension protrusion 4a ′ is formed following the protrusion 4a that covers the gap between the sword tip rear portion 1b of the outer hook 1 and the back plate 4.
Are formed. The extended protrusion 4 a ′ extends along the edge of the outer peripheral portion 1 c following the sword tip rear portion 1 b of the outer hook 1 and covers a gap formed between the outer peripheral portion 1 c and the back plate 4.

In the clockwise full-rotation vertical hook constructed as described above, even if the upper thread 6 sags at the start of sewing or empty stitching, the upper thread is extended as shown in FIG. Four
It does not go into the gap between the outer peripheral portion 1c following the sword tip rear portion 1b of the outer hook 1 and the back plate 4 because it is caught by a ', and therefore,
It does not cut in the gap. It is also possible to prevent the upper thread 6 from coming off in the direction of the mounting axis of the outer hook 1 shown by the arrow B.

The example of integrally forming the extended protrusion 4a 'on the back plate 4 has been described above. However, another member 7 having a protrusion 7a corresponding to the extended protrusion 4a' shown in FIG. Alternatively, as shown in FIGS. 7 (2) and 7 (3), the back plate 4 may be fixed with screws or the like.

[0016]

Since the present invention is configured as described above, it has the following effects.

That is, even if the slack of the upper thread becomes large at the time of starting sewing or empty stitching, the needle thread is not caught in the gap between the outer hook and the back plate and is not dislocated in the hook axis direction. Therefore, needle thread breakage and needle breakage do not occur, and stable sewing can always be performed.

[Brief description of drawings]

FIG. 1 is a view of a conventional DP shuttle, (1) is a front view,
(2) is a plan view.

FIG. 2 is a view of an outer pot of a conventional DP pot, (1) is a front view, and (2) is a side view.

FIG. 3 is a view of a back plate of a conventional DP shuttle, (1) is a front view, and (2) is a side view.

4A and 4B are diagrams for explaining the behavior of the upper thread when a needle thread loop is captured in a conventional DP shuttle, (1) is a perspective view, (2) is a plan view during normal sewing, and (3) is the start of sewing. It is a top view at the time.

FIG. 5 is a diagram relating to the DP shuttle of the present invention, (1) is a front view of the back plate, (2) is a plan view of the back plate, (3) is a side view of the back plate, and (4) is an outer hook. It is a top view of the hook near the tip of the sword.

FIG. 6 is a view for explaining the behavior of the upper thread when the needle thread loop is captured in the DP shuttle of the present invention, (1) is a perspective view,
(2) is a plan view and (3) is a side view.

FIG. 7 is a diagram relating to an auxiliary member in the DP shuttle of the present invention, (1) is a perspective view of the auxiliary member, (2) is a back view of a back plate to which the auxiliary member is attached, and (3) is a side view thereof. Is.

[Explanation of symbols]

 1 Outer hook 1a Sword tip 1b Sword tip rear part 1c Outer peripheral part 4 Back plate 4a Projection part 4a 'Extension projection part 6 Needle loop

Claims (1)

[Claims] 1. A projection provided on the back plate for covering a gap between a rear part of the outer hook and the back plate of the outer hook, followed by an edge of an outer peripheral part of the outer hook continuing to the rear part of the outer hook. A clockwise full-rotation vertical hook that extends and has an extension protrusion on the back plate that covers the gap between the outer peripheral portion and the back plate.