JPS6020991Y2 - Upper thread control device in horizontal hook - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for improving the shape of a zigzag seam in a zigzag seam with a horizontal hook.

When performing zigzag stitches using a conventional zigzag sewing machine, most of the stitches at the right needle drop point are shown in Figure 1A, and details are shown in Figure 2.
A normal stitch having the structure shown in the figure is formed, but as shown in FIG. 1 B1 in detail, as shown in FIG. It slips under the needle thread 22 and on the fabric, the needle thread 22 on the thread line side
A cross seam is formed that crosses over the seam, and as a result of this cross seam, when the seam is observed as a whole, it becomes uneven and looks unsightly, and a cross seam is formed, and as a derivative phenomenon, As shown in Figure 1C, this method has the disadvantage that walnuts occur in the seams, further emphasizing the irregularity of the seams.

The purpose of the present invention is to prevent the occurrence of the above-mentioned cross stitches, and in order to investigate the cause of the occurrence of cross stitches, changes in the condition of the needle thread loop are shown in Figs. 4 a to 4C. When the needle thread loop 20 shown in the figure is released from the inner hook 2, the inertia force at that moment causes the needle thread 20 on the take-up side to
This is because the thread is blown to the opposite side of the upper thread 22 on the thread liner side before it is tightened, and that state is maintained by the thread liner action of the thread 22 on the thread liner side.

Therefore, if a protrusion 24 is provided near the center of the zigzag stitch on the top surface of the inner hook 2 or the back surface of the throat plate 8, the needle thread loop 20 will be locked by the protrusion 24 as shown by the dotted line in FIG. If the thread loop 20 is held even after it is released from the right end 25 of the inner hook 2, and then released by the lifting movement of the thread take-up, the needle thread 21 on the thread take-up side will jump up more than in the conventional case. The formation of a cross stitch can be avoided to a large extent because the needle thread 22 on the stitch side does not jump to the other side due to a delay.

However, if the convex part 24 is a simple protrusion of a rigid body, the needle thread loop 20 itself moves very irregularly and may come off and cannot be retained until the desired time, making it impossible to achieve the purpose of retaining the thread as described above. It is not perfect and the expected effect cannot be obtained.

Therefore, even if the needle thread loop 20 moves irregularly, it is desired to develop a convex part, that is, a needle thread loop retention member, which can reliably capture the irregular movement and hold it until the appropriate release time, thereby completely achieving the purpose of retention. was.

The present invention covers a range from a line connecting the center of the needle hole in the throat plate of a horizontal hook type zigzag sewing machine to the center of the bobbin installed in the inner hook, to the center of the needle hole in the throat plate and the periphery of the lower thread pull-out side edge of the bobbin chamber. An upper thread loop retaining member 26 is provided with a fiber bundle made of a flexible elastic material, polyurethane resin, polyacetal resin, etc., and the tip 27 of the retaining member is brought into light contact with the opposing portion, or the retaining member is The member 26 is provided with a hook-shaped needle thread locking point so that the needle thread loop is held for a while until an appropriate time for forming the seam shown in FIG. 5d, and then released from the hook. It is something.

The present invention will be described below based on an embodiment. In FIGS. 6 to 8, 1 is an outer hook whose tip part that captures the upper thread rotates in a horizontal plane, and 2 is an inner hook that is fitted into the outer hook. , 3 is an opener that prevents the rotation of the inner pot, and these are the main parts of a horizontal hook. At the bottom of the outer hook 1, there is an outer hook support that rotatably supports the outer hook on the machine frame. A shaft 5 is provided vertically, and a gear for driving the outer hook is provided on the shaft.

The inner hook 2 is fitted into the outer hook 1, and has an opener 3 in the rotational direction, a radial race surface 6 of the outer hook 1 in the radial direction, and a thrust race surface 7 in the vertical direction. It is regulated by the throat plate 8, the inner hook holder 9, the sliding plate 30, and the like.

The opener 3 is rotatably attached to a part of the machine frame (not shown) with an opener shaft 10 provided at the center parallel to the outer hook support shaft 5, and has tip portions 11 on the left and right. A cam 31 is provided at the lower part of the outer pot 1.
(FIGS. 9 and 10), the left and right ends 11 and 12 are caused to swing in synchronization with the rotational movement of the outer hook 1, and the left and right tips 11 and 12 are moved toward the inner hook 2.
The rotation of the inner pot 2 is restricted by engaging alternately with the regulation grooves 13 and 14 provided in the regulation grooves 13 and 13.
The needle thread loop is passed through the gap created between the inner hook 2 and the inner hook 2, and is released from the inner hook 2 to form a stitch.

In addition, a magnet 15 is embedded in the inner bottom of the outer pot 1, which attracts an iron plate 16 buried in the lower part of the inner pot 2 to reduce vibrations of the inner pot 2 caused by the rotation of the outer pot 1. It is designed to stabilize the wearing condition.

A cylindrical bobbin chamber 17 is formed at a position slightly away from the center of the inner hook 2, and a bobbin thread tension adjusting member 18 is formed at an appropriate location in the chamber to adjust the tension of the bobbin 19. The thread is led out of the inner hook 2 through the tension adjustment member 18.

Reference numeral 26 denotes a retaining member for the needle thread loop, which is shown in FIGS. 6 and 7 as being formed from a fiber bundle. In FIG. It is provided on the lower surface of the throat plate 8, and its downward tip 27 is brought into contact with the inner hook 2.

The one in Figure 7 has a retaining member 26 attached to the bobbin peripheral area 28 of the inner pot.
The needle thread loop is temporarily held by bringing the tip 27 of the member into light contact with the back surface of the throat plate 8 or the sliding plate.

In the one shown in FIG. 8, a retaining member 26 made of polyurethane, polyacetal, etc. is provided around the edge 28 of the inner pot 2, and the tip 27 is hook-shaped, and the tip 27 of the hook-shaped portion allows the retaining member 26 to be The thread loop is temporarily captured and held.

FIG. 9 shows the side where the retaining member 26 is formed of a fiber bundle and provided on the sliding plate 30, with the downward tip 27 in contact with the bobbin thread pull-out side edge 29 of the inner hook 2 and attached to the take-up bin (not shown). The upper thread loop is held until the upper thread loop is pulled up by the thread pulling action.

The retaining member 26 shown in FIG. 10 is made of a resin material such as polyurethane or polyacetal, and is fitted and fixed to the sliding plate 30. It is brought into light contact with the thread pull-out side edge 29, and is held in place until the appropriate time when the needle thread loop 20 is pulled up by the thread take-up.

The present invention is constructed as described above, and its operation will be described as follows: As described above, since the needle thread loop retaining member 26 is disposed around the lower thread pull-out side edge of the inner hook 2, the inner hook 2
The loop of the upper thread released from the upper thread can be retained by the retaining member until an appropriate time for stitch formation, and it is possible to prevent the upper thread from jumping up, which is detrimental to stitch formation.

Moreover, since the retaining member 26 is made of a flexible elastic material, the retaining action is carried out by the elasticity of the retaining member itself until a predetermined point in time when the upper thread is pulled up on the thread take-up. When the pulling force of the thread take-up acts to increase the tension on the upper thread held in the holding member 26, the tip 27 bends and the upper thread passes through. The inner pot is released and the seams are shaped (Figure 5).

Therefore, normal stitches as shown in the second figure can be made in succession without creating cross stitches as shown in the third figure.

Since the present invention is constructed and operates as described above,
The harmful cross stitches that often occur in the zigzag stitching of conventional sewing machines are completely removed, and the intended purpose can be completely achieved by always producing good stitches without causing thread walnuts. There is a method that can further improve the effect of sewing, is easy to implement, and has extremely high usability.

[Brief explanation of the drawings] Figure 1 shows the zigzag stitch made by a conventional sewing machine, Figure 2 shows the countries in which the normal stitch is made, Figure 3 shows the configuration of the cross stitch, and Figure 4 shows the process of making the cross stitch. Fig. 5 is a progress diagram of the formation of zigzag stitches when a needle thread loop retention member is provided, Fig. 6 is a perspective view of the first embodiment of the present invention, and Fig. 7 is a perspective view of the second embodiment of the present invention. 8 is a perspective view of the third embodiment of the present invention, and FIG. 9 is a perspective view of the third embodiment of the present invention.
The figure is a cross-sectional side view of the fourth embodiment of the present invention, and FIG. 10 is a cross-sectional side view of the fifth embodiment of the present invention. In the figure, 2 is an inner hook, 9 is a throat plate, 17 is a bobbin chamber, 19 is a bobbin, 26 is an upper thread loop retention member, and 80 is a needle hole in the throat plate.

Claims (1)

[Scope of utility model registration request] In the area surrounded by the line connecting the needle hole 80 of the throat plate 8 and the center of the bobbin 19 attached to the inner hook 2, and the line connecting the needle hole 80 of the throat plate 8 and the bobbin thread outlet of the bobbin chamber 17. A needle thread loop retaining member 26 made of a flexible elastic material is provided on either the inner hook or the throat plate facing each other so that the end of the retaining member contacts the throat plate or the inner hook. Upper thread control device in the hook.