JPH0246855Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a presser foot device for a sewing machine in which a presser foot for a workpiece presser moves up and down in conjunction with a needle bar.

[Prior art] Conventionally, as this type of presser device, the
The most commonly known type is one in which a coil spring is fixed to a needle bar, as shown in Japanese Patent No. 3037. In this presser foot device, the upper thread is passed from the middle of the coil spring into the inside of the coil spring, where the upper thread is bent and brought out from the lower end of the coil spring, and then guided to the eye of the needle.

In addition, as another conventional presser device,
There is one shown in Publication No. 33345. This presser foot device includes a cylindrical body provided on the lower end surface of a needle bar, and a coil spring interposed between the lower end surface of the needle bar and a stepped portion of the cylindrical body.

[Problem to be solved by the invention] According to the presser foot device disclosed in the above-mentioned Japanese Utility Model Publication No. 32-3037, threading work is very troublesome because the upper thread is guided through the coil springs to the eye of the needle. be. Also, when sewing work cloth, when the needle bar descends and the coil spring compresses the work cloth, the coil spring is compressed and pinched by the coil spring itself, which adds extra resistance to the upper thread. As the needle thread tension changes, skipped stitches tend to occur, and beautiful stitches may not be obtained.

Furthermore, according to the above-mentioned Japanese Utility Model Publication No. 59-33345, there is no problem that the needle thread is pinched by the compression of the coil spring, but the needle thread is attached by interposing the coil spring in the cylindrical body and inserting the sewing needle therein. Therefore, the mounting mechanism becomes complicated and expensive. Furthermore, since the guide hole is opened in the lower peripheral surface of the cylindrical body and the upper thread is guided to the needle hole through the guide hole, the upper thread may be bent at the guide hole and get caught at that part. There was also the problem that the needle thread tension changed, resulting in skipped stitches as described above.

[Purpose of the invention] Therefore, the present invention was devised to solve the conventional problems.The purpose of this invention is not only to securely hold the processed fabric, but also to provide a simple structure that can be used during sewing work. To provide a presser foot device for a sewing machine that allows easy threading and provides beautiful seams on workpiece cloth.

[Means for Solving the Problems] In the cloth presser device of the sewing machine of the present invention, a needle is attached to the lower end of the needle bar supported so as to be movable up and down toward the work cloth placed on the bed. A coil spring-shaped workpiece presser foot with one end fitted is provided at the lower end of the needle bar so as to surround the needle, and a coil spring-type presser foot is provided on the outer peripheral surface of the lower end of the needle bar. The needle thread insertion hole is cut out to allow the needle thread to pass through the needle and guide the needle thread into the eye of the needle.

[Operation] With the above structure, the needle thread introduced from the needle thread insertion hole of the needle bar is inserted into the inside of the coil spring without being bent, and then taken out from the lower end of the coil spring and guided to the eye of the needle.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

The needle bar 10 is supported by an arm of the sewing machine main body (not shown) so as to be able to reciprocate up and down toward the work cloth W placed on the bed 22 by a driving device (not shown). Also, the needle 12 is attached to the screw 14 at the lower end of the needle bar 10.
Fixed by The needle thread insertion hole 16 is connected to the needle bar 1.
It consists of a recessed part formed in the outer peripheral surface of the lower end of the needle bar 10, and is formed so as to reach the lower end surface along the axial direction of the needle bar 10. The presser foot 18 has a coil spring shape, and one end of the presser foot 18 is fitted onto the lower end circumferential surface of the needle bar 10 via a ring-shaped fitting member 20 . Then, when the needle 12 penetrates the work cloth W and descends, and then rises and comes out of the work cloth W, the work cloth W is attached to the bed 22 around the needle 12 as the needle 12 moves up and down. It is designed to prevent the needle from fitting into the needle hole of the provided throat plate (not shown) or from rising above the upper surface of the throat plate. The fitting member 20 consists of a ring with a portion cut out, and its outer diameter is the same as that of the coil spring 18.
The coil spring 18 is inserted into the tightly wound upper end portion 18a of the coil spring 18, and is held by the mutual elastic force so as not to fall off. and,
The fitting member 20 is attached to the needle bar 10 together with the coil spring 18.
The needle 1 is inserted into the lower end of the needle 1 by the screw 14.
Fixed together with 2. Note that when fixing the fitting member 20 to the needle bar 10, the partially cut out portion of the fitting member 20 is inserted into the needle thread insertion hole 16 of the needle bar 10.
It is configured such that the upper thread Y is easily guided into the coil spring 18 through the upper thread insertion hole 16.

The operation of this embodiment having the configuration described above will be explained.

FIG. 1 shows each member when the needle bar 10 is located near the top dead center. In this state, the upper thread Y
is introduced into the coil spring 18 through the upper thread insertion hole 16 and inserted into the eye hole 13 of the needle 12.

At this time, as described above, the needle thread insertion hole 16 cut out in the outer circumferential surface of the lower end of the needle bar 10 extends along the axial direction of the needle bar 10 to the lower end surface, so that the needle thread Y is passed upward. When inserted through the thread insertion hole 16, the tip of the upper thread Y is introduced into the coil spring 18 along the axial direction of the needle bar 10 so as to be guided by the upper thread insertion hole 16. Therefore, the operation of inserting the needle thread Y into the eye hole 13 of the needle can be performed reliably and easily.

Then, the work cloth W is placed on the bed surface 22, and the needle bar 10 is driven by a drive device (not shown). When the needle bar 10 starts descending, the coil spring 18 also descends, and when the needle bar 10 further processes, the needle 12 touches the work cloth, and then the coil spring 18 touches the work cloth W.
come into contact with. When the needle bar 10 is further processed, the coil spring 18 is compressed and strongly presses the work cloth W around the needle 12 onto the bed surface 22 (see FIG. 2).

When the needle bar 10 starts to rise from this state, the coil spring 18 gradually weakens the compression of the coil spring 18 while preventing the work cloth W from lifting up.
When the needle bar 10 further rises, the coil spring 18
Release the pressure on the work cloth W.

As described in detail above, in this embodiment, the needle thread insertion hole 16, which is cut out along the axial direction of the needle bar 10, is provided on the outer peripheral surface of the lower end of the needle bar 10.
When threading the upper thread Y through the second hole, the tip of the upper thread Y is not guided to the outside of the coil spring 18, and the path of the upper thread Y becomes straight, allowing threading work to be performed reliably and easily. Can be done.

Also, the upper thread Y passes through the upper thread insertion hole 16 to the coil spring 1.
8, when the coil spring 18 is compressed during processing of the needle bar 10, the needle thread Y will not be pinched by the compression of the coil spring 18, and therefore extra resistance will be applied to the needle thread Y. Beautiful stitches can be obtained without skipping stitches due to changes in needle thread tension.

[Effects of the invention] As described above, according to the invention, not only can the work cloth be reliably pressed using the coil spring-like presser foot, but also the upper thread insertion hole formed in the outer circumferential surface of the needle bar is provided. Since the upper thread can be easily introduced into the inside of the presser foot and passed through the eye of the sewing needle, threading work can be performed reliably and easily, and work efficiency can be greatly improved. Another advantage is that the needle thread does not get caught on the presser foot during sewing and beautiful seams can be formed.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the presser foot device in a state where the needle bar is located near the top dead center, FIG. 2 is a front view showing the presser foot device when the needle bar is located near the bottom dead center, and FIG. The figure is a sectional view taken along the line A-A in FIG. 1. In the figure, 10 is a needle bar, 12 is a needle, 13 is an eye hole, 1
6 is a notch, and 18 is a coil spring.

Claims (1)

[Scope of utility model registration request] A needle 12 is attached to the lower end of a needle bar 10 that is supported so as to be able to move up and down toward the work cloth placed on the bed. A workpiece presser foot 18 is provided to surround the needle 12, and the lower end outer peripheral surface of the needle bar 10 allows the needle thread to be inserted into the spring-like presser foot 18. Upper thread insertion hole 1 that can guide the thread to the eye hole 13 of the needle 12
A presser foot device for a sewing machine, characterized in that 6 is formed with a notch.