JPS5841911Y2 - Full rotary hook for sewing machine - Google Patents

Description

[Detailed description of the invention] The needle thread loop fall prevention stopper (wall) 4 of the conventional full-rotation hook 1 for a sewing machine is shown in FIG. It was a parallel long hole stopper (wall) as shown in the figure.

Therefore, when sewing with this type of sewing machine, the beams, M, and R
Since the needle rise (distance where the needle 3 rises from the bottom dead center and matches the point 10) of M and R is different, the amount of thread to form a loop from the upper surface of the throat plate 5 is different. If the distance g from the needle 3tt, 3°3' to the stopper 4 is kept constant, the amount of yarn moving in L is large and the loop 13'' on the tip side becomes large and tends to fall down, whereas in R Since the amount of thread that moves is minimal, the same amount of thread as L is formed as a loop on the stopper 4 side, and only an elongated loop 13' is formed on the tip side.

That is, as shown in Fig. 5, the width of the rear loop of the needle is l'', l, l.
' and become smaller sequentially.

Due to the above loop formation conditions, the tip of the sword 10 is loop 13"
, 13. When hooking 13', the loop in R is too small and it is difficult for the tip 10 to scoop up the loop 13', and in the case of R, the loop 13'' is too large and there is a risk of it falling over. It was the cause.

The present invention was proposed to solve the above-mentioned conventional drawbacks, and the loop shape is neither too large nor too small in M and R, and can be sewn with any fabric of any material. To provide a full-rotation hook for a sewing machine whose tip can reliably hook a loop and perform sewing without skipping stitches.

The embodiment of the present invention will be described above with reference to the drawings. In the embodiment shown in Figs. 1 to 3, the same parts as in the conventional case shown in Figs. 4 and 5 will be indicated by the same reference numerals. .

In FIGS. 1 to 3, needles 3", 3.3' are attached to the left, middle, right (L, M, R) It is configured to fall to the baseline.

That is, the surface of the loop stopper 4a is inclined at an angle of θ with respect to a line passing through the center of the needle so that the long hole 2a has a wide L and a narrow R.

Reference numeral 5 denotes a needle plate on which a fabric 6 is placed, and a sewing thread 8 is passed through the needle hole 7 to form loops 9'' and 9.9'.

a, l), and c are the distances from the front surface of the needles 3'' and 3.3' to the front surface of the loop stopper 4a, and are successively smaller as M and R.

Y is needle 3''. Loop 9'' from the back of 3.3', 9.9'
Distance to the inner surface of, 10 is the tip of the sword, 11", 11.11
' indicates the position of the tip 10 when hooking the loops 9'' and 9.9'.

Next, the action will be explained.

When the needles 3" and 3.3' are moved up and down, the needles penetrate the fabric 6 on the throat plate 5 at the L, M, and R base lines, and the elongated hole 2a of the full-rotation hook 1 is located in the central part of the coast. , then needle 3”, 3.3
When ' reaches the bottom dead center, the sewing thread 8 is pulled to the maximum, and the loops 9'' and 9.9' of the sewing thread 8 are hooked at the point where the needle meets the raised tip 10 of the fully rotary hook 1.

In this case, the size of the loops 9'' and 9.9' is determined by the angle θ of the loop stopper 4a, so that the size of the loops 9'' and 9.9' is determined by the angle between the tip 10 and the needle 3''.
, 3.3', loops 9'' and 9.9' having substantially the same shape can be formed at the rear of the needle even if the M and R are different.

As explained above, in the present invention, the elongated hole provided in the needle drop part of the full-rotation hook is shaped to have a loop stopper surface that is inclined at an angle θ with respect to the left-right swing locus of the needle center. There is a dimensional difference in distance that decreases from left to right, so even if the position of the tip changes when hooking the loops on the left, middle, and right base lines, the distance between the loops on the left, middle, and right The needles are formed to have the same size Y from the outer periphery of the needle to the rear surface.

Therefore, the tip can reliably hook the loop, and sewing can be performed without skipping stitches at any position of the needle base line, M, or R.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a full rotary pot showing an embodiment of the present invention;
The figure is an explanatory diagram showing the meeting of the needle and the tip of the sword, and the third figure is the left, middle,
A vertical cross-sectional view showing the needle position relative to the loop stopper at the right position and the condition of the loop, FIG. 4 is a plan view showing an example of a conventional full-rotation hook, and FIG. FIG. 6 is a vertical cross-sectional view showing the position of the needle relative to the loop stopper and the condition of the loop at the middle and right positions. Explanation of main parts of the diagram 1...Full rotary pot, 2a.
...Long hole, 3.3', 3" ...Needle, 4a
......Loop stopper, θ...Angle of inclination, 8...Sewing thread, 9.9', 9''...
Loop, a, l), c...needle (3, 3', 3''
) from the front surface of the front loop stopper 4a,
10...The tip of the sword.

Claims (1)

[Scope of utility model registration request] In a zigzag sewing machine having left and right needle drop positions, the elongated hole provided in the needle drop part of the full rotary hook has a shape having a loop stopper surface inclined at an angle θ with respect to the left and right swing locus of the needle center, A full-rotation hook for a sewing machine, characterized in that the distance between the outer periphery of the needle and the loop stopper surface is wide on the left base line and narrow on the right base line.