JPH0884873A - Flat stitch sewing machine - Google Patents

Abstract

(57) [Summary] [Purpose] Maintaining the upward movement of the upper feed mechanism 16 in a good condition,
The workability and reliability of the flat stitch sewing machine can be improved. [Structure] The upper feed dog 17 of the upper feed mechanism 16 is extended in the space above the spreader 13 to ensure a sufficient amount of lifting of the upper feed dog 17 regardless of the spreader 13 and to prevent the upper feed dog 17 from moving upward during a presser foot lifting operation. A structure configured to prevent interference between the feed dog 17 and the spreader 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat stitch sewing machine for sewing top decorative stitches.

[0002]

2. Description of the Related Art Conventionally, there has been known a flat stitch sewing machine constructed so that a spreader is reciprocally moved in a substantially horizontal plane in synchronization with a needle bar to perform an upper cover stitch on a material to be sewn.
The spreader is configured to perform an arcuate movement from the side of the needle bar to the front, and the supply position of the upper thread hung on the tip of the spreader is a direction substantially orthogonal to the feed direction of the workpiece. The decorative thread is sewn by moving it at a predetermined timing.

In a flat stitch sewing machine using such a spreader, there is a gap between the lower work to be sewn by the feed force of the lower feed dog and the upper work to be laid on the lower work. Since it is apt to occur, it has been conventionally proposed to provide an upper feed dog for giving a feed force to the upper workpiece in order to eliminate it.

[0004]

However, when the flat feed stitching machine is provided with the upper feed dog which is normally used, the problem arises that the upper feed dog interferes with the above-mentioned spreader. . Specifically, as shown in FIG. 2, the spreader 2 that reciprocates circularly in a substantially horizontal plane from the side to the front of the needle bar 1 is arranged at a predetermined height position required for decorative sewing operation. On the other hand, if the normal upper feed dog 3 is attached as it is, the arm portion 3a of the upper feed tooth 3 extends through the space below the spreader 2 to the front side of the needle bar 1. Become involved.

However, the space below the spreader 2 is narrow, and the arm portion 3a of the upper feed dog 3 interferes with the spreader 2 as it is, or even if it is not, the upper feed dog 3 can be lifted when the presser foot is raised. You will not be able to secure the required amount of climb. It should be noted that it is possible to arrange the arm portion 3a of the upper feed dog 3 so that the arm portion 3a is largely removed laterally, so that the upper feed dog 3 can be prevented from interfering with the spreader 2 in that case. Get in the way,
It cannot be adopted.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a flat stitch sewing machine capable of ensuring an ascending operation of the upper feed mechanism and a good positional relationship with the spreader when the upper feed mechanism is provided.

[0007]

To achieve the above object, a first aspect of the present invention is a flat plate equipped with a spreader that reciprocates in synchronization with a needle bar in order to perform top decorative stitching on sewing objects which are vertically stacked. In the sewing machine, an upper feed mechanism for feeding the upper workpiece to the needle bar is provided, and the upper feed mechanism extends to the front side of the needle bar through the space above the spreader. It is configured to have.

In the second invention, in addition to the structure of the first invention, the upper feed dog of the upper feed mechanism extends to the front side of the needle bar through a space on the opposite side of the spreader with respect to the needle bar. It is configured to do.

[0009]

In the flat stitch sewing machine according to the first aspect of the present invention having such a structure, since the upper feed dog of the upper feed mechanism extends into the space above the spreader, the upper feed dog is
It is possible to raise without being restricted by the spreader, and the amount of rise in the lifting operation of the upper feed dog can be sufficiently secured regardless of the spreader.

In addition to this, in the second invention, since the upper feed dog of the upper feed mechanism extends into the space on the opposite side of the spreader, the upper feed mechanism can be easily arranged regardless of the spreader. It is like this.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. As shown in FIGS. 1, 2, and 3, three sewing needles 12 are attached to a needle bar 11 that is reciprocally driven in a substantially vertical direction. These sewing needles 12 are arranged in a direction substantially orthogonal to the feeding direction (X direction in the drawing) of the material to be sewn (see reference numeral A in FIG. 2), and the upper thread (not shown) is spread from the spreader 13. Is being supplied.

The spreader 13 is rotatably supported with respect to the presser bar 14, and is structured to swing by a drive mechanism as shown in FIG. Further, the spreader 13 has an arm portion 13a extending in a substantially arc shape, and the arm portion 13a is
The sewing needle 12 extends from one side (back side in the drawing) to the front side (upstream side in the feeding direction of the workpiece). A needle thread (not shown) is hung on the tip of the arm portion 13a, and the base side of the arm portion 13a is connected to a swing shaft (not shown). It is configured to reciprocate in an arc shape in a substantially horizontal plane from the (back side in the drawing) to the front side (upstream side in the feeding direction of the sewing object). As a result, the supply position of the upper thread hung on the tip end of the spreader 13 is moved at a predetermined timing in a direction substantially orthogonal to the feed direction (X direction in the drawing) of the workpiece, and the sewing of the decorative thread is performed. It is supposed to be done.

Further, a pressing bar 14 biased downward is provided at the rear of the needle bar 11 (downstream side in the feeding direction of the workpiece), and a pressing plate 15 is provided at the lower end of the pressing bar 14.
Is attached. The presser plate 15 presses the sewing object placed on the needle plate (see reference numeral B in FIG. 2) on the sewing machine bed side from above with a predetermined force. 2 together with the upper feed mechanism 16 to be described
It is configured to be raised like.

The upper feed mechanism 16 applies a feed force to the upper workpiece, and the lower workpiece to which the feed force of a lower feed tooth (not shown) acts is placed on the lower workpiece. The upper feed dog 17 is provided in front of the sewing needle 12 (upstream side in the feeding direction of the sewn object) in order to prevent a deviation from the upper side sewn object. This upper feed dog 17
Is pressed against the workpiece to be sewn on the upper side through a window 15a provided in the pressing plate 15, and the upper feed dog 17 draws an arcuate locus in synchronization with the needle bar 11 by a drive mechanism (not shown). As a result, the upper sewing object is configured to be fed toward the needle drop point.

At this time, the arm portion 17 of the upper feed dog 17
a is arranged in a space on the opposite side (front side in the figure) of the spreader 13 with respect to the needle bar 11, and the arm portion 17a of the upper feed dog 17 passes through the space above the spreader 13 and is a needle. It extends to the front side of the rod 11. Thus, the interference between the arm portion 17a of the upper feed dog 17 and the spreader 13 is prevented as follows.

That is, when thread trimming is to be performed at the end of sewing, the spreader 1 is used as shown in FIG.
3 is located on the front side of the sewing needle 12, and the arm portion 17a of the upper feed dog 17 intersects the spreader 13 in a plan view. However, in the flat stitch sewing machine according to this embodiment, since the arm portion 17a of the upper feed dog 17 extends into the space above the spreader 13 as described above, the arm portion 17a of the upper feed dog 17 is formed.
Can be raised without being restricted by the spreader 13.

For example, when the thread trimming is completed, the presser foot lifting operation is executed, and the upper feed mechanism 16 causes the presser plate 15 to move as shown in FIG.
Even when the upper feed dog 17 is lifted together with the upper feed dog 17, the lift amount of the upper feed dog 17 is sufficiently secured irrespective of the spreader 13. Therefore, as described above,
Interference between the arm portion 17a of the and the spreader 13 is completely prevented.

Further, in this embodiment, since the arm portion 17a of the upper feed dog 17 is arranged in the space on the opposite side of the spreader 13 with respect to the needle bar 11, the arrangement space for the upper feed mechanism 16 is secured wide. And therefore spreader 13
The upper feed mechanism 16 can be easily arranged regardless of the above.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say. For example, in the above embodiment, the upper feed dog 17 of the upper feed mechanism 16 is
Is placed in the area opposite the spreader 13,
It is also possible to arrange both in the area | region on the same side with respect to the needle bar 11.

Further, in the above embodiment, the needle bar, the upper feed shaft, and the presser bar are arranged in this order from the upstream side in the feeding direction of the workpiece, but the needle bar, the presser bar, and the upper feed shaft are arranged in this order. You can also

[0021]

As described above, in the flat stitch sewing machine according to the first aspect of the present invention, the upper feed dog of the upper feed mechanism is extended to the space above the spreader, and the amount of rise of the upper feed dog is sufficiently increased regardless of the spreader. The upper feed mechanism and the spreader can be prevented from interfering with each other when the presser foot is raised, so that the upward movement of the upper feed mechanism can be maintained well and the work of the flat stitch sewing machine can be performed. The reliability and reliability can be improved.

The flat stitch sewing machine according to the second invention is
In addition to the first aspect of the invention, the upper feed dog of the upper feed mechanism is arranged in a region on the opposite side of the spreader so as to secure a wide arrangement space for the upper feed mechanism. The feed mechanism can be easily arranged, and the productivity and workability of the flat stitch sewing machine can be further improved.

[Brief description of drawings]

FIG. 1 is an external perspective explanatory view showing a main part of a flat stitch sewing machine according to an embodiment of the present invention in a state at the end of a sewing operation.

FIG. 2 is an external perspective view showing the state of the presser foot lifting operation of the flat stitch sewing machine shown in FIG.

FIG. 3 is an explanatory plan view showing a state in which a spreader used in the flat stitch sewing machine of the embodiment shown in FIG. 1 is rotationally supported with respect to a presser bar.

FIG. 4 is an external perspective view showing a case where general configurations are simply combined.

[Explanation of symbols]

 11 Needle bar 13 Spreader 13a Arm part 14 Presser bar 16 Upper feed mechanism 17 Upper feed tooth 17a Arm part

Claims (2)

[Claims] 1. A flat stitch sewing machine equipped with a spreader that reciprocates in synchronization with a needle bar in order to sew a top-to-bottom object to be sewn on top and bottom. A flat stitch sewing machine comprising an upper feed mechanism for feeding, wherein the upper feed mechanism has an upper feed tooth that extends to a front side of a needle bar through a space above the spreader. 2. The flat stitch sewing machine according to claim 1, wherein the upper feed dog of the upper feed mechanism extends to the front side of the needle bar through a space opposite to the spreader with respect to the needle bar. A characteristic flat stitch sewing machine.