JP2558603Y2 - Staggered sewing machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a staggered sewing machine which performs two-point zigzag stitching on a sewn cloth (fabric) with a needle.

[0002]

2. Description of the Related Art The zigzag sewing machine shown in FIG. 3 has been widely known before this application. It uses an eccentric cam 12 as a swing cam. When the eccentric cam 12 rotates around the cam shaft 13, the upper end of the thrust rod 6 in which the lower hole 6a is engaged with the eccentric cam 12 makes an approximate circular motion. By the way, the left end 8b of the swinging drive link 8 connected to the swinging rod 6 is supported so as to be able to move only in the horizontal direction. However, since the upper end of the swinging rod 6 performs an approximate circular motion, it is constantly moved. Move horizontally. Therefore, the needle bar on the left side also constantly moves in the horizontal direction, and the needle at the end of the needle bar does not stop with respect to the fabric surface direction during sewing.

[0003] In addition, a staggered sewing machine and a needle that use two eccentric cams as the needle swing cams, combine their movements and transmit the movement from the needle swing rod to the needle bar, and create a section where the movement of the needle with respect to the fabric surface direction is stopped. There is a zigzag sewing machine that uses a triangular cam as a swing cam and uses the pause section to create a section in which the movement of the needle in the fabric surface direction pauses.

[0004]

The staggered sewing machine having one eccentric cam described above is suitable for high-speed operation, but the needle tip does not stop in the direction of the fabric surface during the swinging operation. When piercing the fabric, a so-called needle flow that moves in the fabric surface direction occurs. For this reason, a large hole of a needle may be formed on the surface of the cloth, or the cloth may be damaged. A staggered sewing machine having two eccentric cams has almost no needle flow. However, since two eccentric cams are required, it is difficult to convert the staggered sewing machine to a popular staggered sewing machine. Furthermore, a staggered sewing machine having a triangular cam does not have a needle flow, but it is difficult to process the triangular cam and a rod that stores the triangular cam, and since the acceleration changes greatly, noise, vibration, and heat are generated when rotating at high speed. Occurs.

An object of the present invention is to provide a staggered sewing machine that can prevent needle flow by adding a simple member.

[0006]

In order to achieve the above object, a staggered sewing machine according to the present invention has a length in which an eccentric cam, a circular hole in which the eccentric cam is fitted, and a roller fixed to a frame are engaged. An eccentric cam rod having a hole formed therein and one end connected to the swinging rod is provided.

[0007]

[Operation] In the zigzag sewing machine configured as described above, when the eccentric cam rotates, the connecting portion of the eccentric cam rod and the swinging rod moves in an elliptical locus, and moves through the swinging rod. Conveyed to the needle bar. Then, a pause section formed at both ends of the elliptical locus where the horizontal movement is substantially stationary is also transmitted to the needle bar.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A staggered sewing machine according to the present invention will be described with reference to FIGS.

The staggered sewing machine includes an eccentric cam 1, an eccentric cam rod 3, a needle swing rod 6, and a needle swing drive link 8.
And a swing width conversion link 10 and the like.

The eccentric cam 1 has a circular shape and is fixed to a cam shaft 2 which rotates at the time of sewing at a position off the center thereof.

The eccentric cam rod 3 has a circular hole 3a and a long hole 3b formed side by side in the longitudinal direction. Circular hole 3a
Of the eccentric cam 1 substantially coincides with the outer diameter of the
The eccentric cam 1 is fitted in the eccentric cam. Moreover, in the long hole 3b,
The roller 4 fixed to the sewing machine frame is engaged. The roller 4 serves as a fulcrum when the eccentric cam rod 3 swings by the rotation of the eccentric cam 1. The eccentric cam rod 3
It can be arranged in the vertical direction as shown in the figure in relation to other member positions, or can be arranged in the horizontal direction on the contrary. In addition, roller 4
By changing the positional relationship between the connecting shaft 5 and the long hole 3b, the movement trajectory of the connecting shaft 5 described later can be freely changed.

The swinging rod 6 is rotatably connected at its lower end to the upper end of the eccentric cam rod 3 by a connecting shaft 5 and at its upper end to the middle of the swinging drive link 8 by a connecting shaft 7.

The left end 8b of the needle swing drive link 8 is supported so as to be movable only in the horizontal direction, and its movement is supported by a needle bar support rod (not shown) connected to the left side. Is transmitted to the needle bar as horizontal reciprocation.

One end of the swing width conversion link 10 is rotatably supported by a shaft 11 fixed to the sewing machine frame.
The other end is the right end 8 a of the needle swing drive link 8 by the connecting shaft 9.
It is connected to.

When the eccentric cam 1 rotates in the zigzag sewing machine configured as described above, the eccentric cam rod 3 swings around the roller 4 as a fulcrum. And as shown in FIG.
The eccentric cam 1 draws a circular locus L1, and the connecting shaft 5 draws an elliptical locus L2. Both ends A and B in the elliptical locus L2 form a so-called pause section that can be regarded as substantially stationary in the horizontal direction.
The elliptical movement of the connecting shaft 5 is transmitted to the connected needle bar on the left side of the left end 8b thereof via the needle swing rod 6 and the needle swing drive link 8, and similarly in the horizontal direction at the amplitude end of the needle bar. A pause is formed in which the movement can be considered substantially stationary. Therefore, if the needles are dropped on the cloth during this pause interval, no needle flow will occur.

[0016]

[Effects of the Invention] The present invention is configured as described above, and has the following effects.

That is, since needle flow does not occur, a large hole is not made or damaged in the fabric. In addition, since it is a change only to add a simple member to the conventional one, it can be sufficiently diverted to a popular staggered sewing machine. Further, unlike a staggered sewing machine using a triangular cam, there is no difficulty in processing the members, and no noise, vibration, or heat is generated, so that the method is suitable for high-speed rotation.

[Brief description of the drawings]

FIG. 1 is a front view of a main part of a staggered sewing machine of the present invention.

FIG. 2 is a diagram showing a trajectory of a connecting portion of the eccentric cam rod and the swinging rod in the staggered sewing machine of the present invention.

FIG. 3 is a front view of a main part of a conventional staggered sewing machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Eccentric cam 3 Eccentric cam rod 3a Circular hole 3b Long hole 4 Roller 5 Connecting shaft 6 Needle swing rod

Claims (1)

(57) [Scope of request for utility model registration] 1. An eccentric cam, an eccentric cam rod having a circular hole into which the eccentric cam is fitted and a long hole into which a roller fixed to a frame engages, and one end of which is connected to a needle swing rod. Staggered sewing machine.