JP3758227B2 - Lock sewing machine presser foot - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a presser foot for a lock sewing machine that can be sewn on a work cloth in parallel with edge stitching and chain stitching.
[0002]
[Prior art]
Conventionally, in some lock sewing machines, in order to ensure fraying prevention, the edge stitching and the chain stitch are sewn to the work cloth in parallel, and after the chain stitch is performed, the edge stitching is performed. It is comprised so that it may be sewn on a work cloth. When the work cloth is not at the sewing point of the chain stitch, the thread used for the chain stitch is intertwined to form an empty ring, and the empty ring is configured to be fed on the needle plate in the cloth feed direction by the feed dog. Yes.
[0003]
Further, a presser foot having a flat surface facing the needle plate is disposed above the needle plate on which the work cloth is placed so that the work cloth is sandwiched between the needle plate and the presser foot. It is configured.
[0004]
In addition, the presser foot has an edge stitching needle drop part and a chain stitch needle drop part that pass through the sewing needle for edge stitching and the sewing needle for chain stitching in the vertical direction corresponding to the respective sewing points. Has been.
[0005]
[Problems to be solved by the invention]
However, since the portion where the feed dog protrudes from the upper surface of the needle plate is separated from the ring stitch needle drop, and the holding surface of the presser foot is flat, the traveling direction of the empty ring is unstable. Thus, among which is sent by the air ring feed dog, its traveling direction is figure for shrinkage of the air ring, an empty ring enters the overedge stitch portion, further, empty ring overedge stitch portion There is a problem that it becomes impossible to sew because of being caught in the presser foot of the sewing machine or entangled with an empty ring and an edge stitching thread.
[0006]
The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a presser foot for a lock sewing machine that can prevent sewing and entanglement of an empty ring and can perform sewing smoothly.
[0007]
[Means for Solving the Problems]
In order to achieve this object, the presser foot of the lock sewing machine of the present invention conveys the work cloth placed on the throat plate in a predetermined cloth feed direction by the feed dog, and the work cloth has a chain stitch and an edge. It can be sewn in parallel with the overlock stitching, and when there is no work cloth at the sewing point of the chain stitch, it is used for a lock sewing machine that can form an empty ring made only of thread used for chain stitching. In particular, the chain stitch needle drop part formed for chain stitching, and the downstream side of the cloth feed direction from the chain stitch needle drop part, and On the right side of the chain stitch needle drop part on the clamping surface for clamping the work cloth together with the needle plate, the edge stitch needle drop part formed for edge stitching and the chain stitch needle drop formed on the clamping surface Before extending to the area facing the feed dog on the downstream side of the cloth feed direction A groove for guiding the air ring, and a groove formed on the upstream side of the downstream end portion of the cloth feeding direction of the end portion of the groove is the sandwiching surface.
[0008]
Thus, in the presser foot of sewing machine of the present invention, the concave groove ring sewing needle vicinity and defining a space extending in the cloth feeding direction, by the space between the lower surface and the needle plate of the presser foot The empty ring formed in (1) is guided to facilitate the progress of the cloth feed direction from the chain stitch needle drop part, and the shrinkage of the empty ring is eliminated.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example in which the present invention is embodied will be described with reference to FIGS. 1 and 2. The cloth feeding direction in the lock sewing machine is indicated by an arrow A, and the horizontal direction orthogonal to the cloth feeding direction is indicated by an arrow L and an arrow R.
[0010]
First, the shape of the presser foot 7 will be described. In the center portion of the presser foot 7, a chain stitch needle dropping portion 7 c for allowing a known chain stitch needle to pass therethrough is formed. On the A side of the chain stitch needle dropping part 7c, on the lower side of the presser foot 7 (corresponding to the clamping surface) 7b, on the R side, a known edge stitching needle drop part for passing a sewing needle for the edge stitching is passed. 7d and 7e are formed. A concave groove 7g and a concave portion 7f that are recessed from the surface of the presser foot 7 are formed on the L side of the edge stitching needle drop portion 7d of the lower surface 7b.
[0011]
The opening of the recess 7f has an elliptical shape that is long in the cloth feeding direction (see FIG. 1) . As shown in FIG. 2 , the depth of the recess 7 f gradually becomes shallower in the A direction . Further, grooves 7g, as shown in FIG. 1, chain-stitch needle portion 7c and the concave portion 7f groove der formed extends over the cloth feeding direction and is, end portions of the grooves in the cloth feeding direction It is formed upstream from the downstream end.
[0012]
Furthermore, the concave groove 7g extending from the chain stitch needle dropping part 7c to the concave part 7f is once refracted and close to the R side. The portion of the concave groove 7g extending in the same position direction as the cloth feeding direction after refraction is a portion facing the feed dog 10 protruding from the needle plate 8. The other end on the A side of the upper surface 7a of the presser foot 7 is configured to be attachable to a presser bar of a known lock sewing machine. Incidentally, the concave portion 7f and grooves 7g correspond to concave groove of the present invention.
[0013]
Next, the configuration of the lock sewing machine main body will be briefly described. The lock sewing machine includes a known chain stitch mechanism, and a known edge stitching mechanism on the A side and the R direction side of the chain stitch mechanism. The chain stitch mechanism is configured such that when the work cloth is not at the sewing point of the chain stitch, the empty ring 12 can be formed by entwining the threads.
[0014]
Also, the needle plate 8 has a chain stitch needle drop portion 8a through which a known chain stitch needle passes, and a known edge stitch stitch needle passes through the A side of the chain stitch needle drop portion 8a. An edge stitching needle drop portion 8b is formed. Shy or the edge needle portion 8b is broad in L-R direction, the rising or edge needle portion 8b, the feed teeth 10 are disposed.
[0015]
Next, the operation of the presser foot 7 when the empty ring 12 is formed will be described.
[0016]
When the empty ring 12 is formed upward by the chain stitch mechanism, the end of the concave groove 7g formed on the lower surface 7b of the presser foot 7 is reached. Therefore, the wall surface of the groove 7g, the traveling direction of the air-ring 12 is changed from the upper horizontally, as air ring 12 is further formed, the air-ring 12 on the downstream side of the cloth feed along the grooves 7g Move toward a certain A side. When the empty ring 12 reaches the recess 7f, the feed dog 10 pulls the empty ring 12 in the A direction, and the empty ring 12 moves to the lower surface 7b along the A direction.
[0017]
Since the recess 7f and the groove 7g define a space extending in the cloth feeding direction between the needle plate 8 and the lower surface 7b, the empty ring 12 can easily travel below the recess 7f and the groove 7g. It has become. Therefore , the empty ring 12 is guided and guided reliably in the concave groove 7g formed on the L side of the edge stitching needle drop portions 7d and 7e. Further, since the shrinkage of the empty ring 12 is eliminated in the space below the concave portion 7f and the concave groove 7g, the empty ring 12 becomes thin. In the present embodiment, since the empty ring 12 is guided by the concave portion 7f and the concave groove 7g, it is not necessary to newly provide parts, and the entanglement between the empty ring 12 and the presser foot 7 can be prevented at a low cost.
[0018]
According to the embodiment of the present invention, Ru is reliably guided by the air ring 12 overlock stitch needle portion 7d · 7e of L side formed groove 7 g. Therefore, it is further prevented that the empty ring becomes entangled with the presser foot and the edge stitching thread and cannot be sewn. Therefore, it can sew smoothly. Further , since the concave portion 7f and the concave groove 7g may be formed, it can be easily processed and created.
[0019]
【The invention's effect】
As is apparent from the above description, according to the presser foot of the lock sewing machine of the present invention, the hollow ring is formed by the concave groove extending from the chain stitch needle drop portion to the region facing the feed dog on the downstream side in the cloth feed direction. Is guided so as to advance in the cloth feeding direction from the chain stitch needle drop portion. In addition, since the end portion of the groove is formed on the upstream side of the downstream end portion in the cloth feeding direction of the holding surface, when the idle ring reaches the end portion of the recessed groove, the empty ring is formed by the feed dog and the holding surface. since sandwiched by moving by being pulled in the cloth feeding direction, at stake in legs and overedge sewing thread empty ring retainer are prevented from falling into unsewable. Therefore, it can sew smoothly. Further, since it is only necessary to form a concave groove on the clamping surface, it can be easily processed and created.
[Brief description of the drawings]
FIG. 1 is a bottom view of the presser foot of sewing machine of the present invention.
FIG. 2 is a cross-sectional view of the presser foot.
[Explanation of symbols]
7c Chain stitching needle drop 7d Edge overlock needle drop 7e Edge over stitch needle drop 7f Concave 7g Concave groove A Cloth feed direction

Claims (1)

The work cloth placed on the throat plate can be conveyed in the predetermined cloth feed direction by the feed dog, and the work cloth can be sewn in parallel with the ring stitch and the edge overhang. When there is no work cloth at the point, it is used for a lock sewing machine capable of forming an empty ring made only of thread used for the chain stitch, and holds the work cloth together with the needle plate above the feed dog. In the presser foot of the lock sewing machine,
A chain stitch needle drop portion formed for the chain stitch;
Formed for edge stitching on the downstream side in the cloth feed direction from the chain stitch needle drop part and on the right side of the chain stitch needle drop part at the clamping surface for clamping the work cloth together with the needle plate. An edged needle drop part,
A concave groove formed on the clamping surface and extending from the chain stitch needle drop portion to a region facing the feed dog on the downstream side in the cloth feed direction, and guiding the idler ring, the end of the groove being the A concave groove formed on the upstream side of the downstream end of the clamping surface in the cloth feeding direction;
A presser foot for a lock sewing machine characterized by comprising:

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