JPH088780Y2 - Overlock sewing machine with presser foot with cloth guide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an overlock sewing machine having a presser foot with a cloth guide.

(Prior Art) Conventionally, an overlock sewing machine is provided with a cloth edge cutting device composed of a fixed knife and a movable knife. The movable knife is arranged above the cloth placing surface of the sewing machine frame in the cutting device. There are two types: upper method supported by the shaft part of the machine and lower method supported by the shaft part arranged below the cloth placing surface. In the upper method, the knife mechanism is used for operating the sewing cloth. In the lower method, when the movable knife is released, a space appears at the trailing edge of the needle plate on the side of the needle plate, and a space appears in the space due to the appearance of the retracted trace of the movable knife. A phenomenon occurs in which the edge of the sewing cloth W is rolled in due to the entry of the edge, and the upper and lower loopers (L ₁ and L ₂ ) are indicated by the arrows in the wound edge of the cloth.
Accidents such as piercing when rotated in the directions of R ₁ and R ₂ and piercing into the sewing cloth cause the problem that the fixing of the looper to the support shaft is displaced and the phase is misaligned (Fig. 5).

(Problems to be Solved by the Invention) The present invention is intended to prevent the cloth edge edge from being caught when the movable knife of a cutting device having a lower movable knife of an overlock sewing machine is released. .

(Means for Solving the Problem) The present invention is designed to prevent the phenomenon that the cloth edge is caught under the needle plate when the lower movable knife of the overlock sewing machine is released, that is, the fixed knife It is characterized in that a member is provided in the vicinity of the disposing portion to prevent the edge of the cloth from coming into contact with the edge of the cloth and dropping the edge of the cloth below the needle plate.

(Operation) The present invention provides a drive shaft that is rotatably supported by a machine frame, a needle bar and a needle that are vertically moved in association with the rotation of the drive shaft, and a sewing machine that is interlocked with the rotation of the drive shaft. A feed dog for moving the cloth, a cloth presser attached to a presser bar of the sewing machine frame so that the cloth can be pressed against the feed dog, and a sewing machine that is rocked in conjunction with the rotation of the drive shaft and cooperates with the needle to sew. A looper that forms the eyes and a movable knife arm that is swingable on the bed machine frame and reciprocates in conjunction with the rotation of the drive shaft, and cooperates with a knife fixed on the machine frame side to sew cloth. In the overlock sewing machine equipped with a lower type movable knife for cutting, the movable knife is rotatably supported on the bed machine frame, and the operating state in which the movable knife cooperates with the fixed knife by the operation of the operation section and the fixed knife. A movable knife switching device capable of switching between a released state for releasing the working relationship, and the cloth pressing device. By placing a vertical part that horizontally protrudes and bends on the fixed knife side closer to the surface of the fixed knife, and by providing a cloth presser with a hook-shaped guide whose end is lower than the blade of the fixed knife, It is also characterized in that the cloth edge of the sewing cloth is prevented from sinking into the hole on the side of the needle plate when the movable knife is released, by the guide attached to the cloth retainer.

(Embodiment) The structure of an embodiment of the present invention will be described with reference to the drawings. The sewing machine frame 1 includes an upper arm machine frame 2 and a lower bed machine frame 3, and a needle is fixed to the lower end of the arm machine frame 2. Of the needle bar is vertically movably supported, and the bed machine frame 3 is rotatably supported by a drive shaft 4. The drive shaft is provided with a ratchet wheel 5 and three eccentric cams 6, 7, and 8. The first eccentric cam 6 drives the upper looper shaft 9 and the second eccentric cam 7 drives the lower looper shaft 10. The upper looper 11 is fixed to the tip of the upper looper shaft 9 and is attached to the lower looper shaft 10. The lower looper 12 is fixed.

 The third eccentric cam 8 drives the movable knife 13.

The movable knife is fixed to one end of a movable knife shaft 15 supported by the tip of a movable knife arm 14 supported by the bed machine frame 3, and a spring 16 mounted on the shaft fixes the movable knife arm 14 on the movable knife arm 14. An operation unit that is pressed against the side surface and rotates the movable knife 13 at the other end of the movable knife shaft 15 into either a use state with the blade above (FIG. 1) or a release state with the blade below. 17 is installed.

The needle plate 18 is fixed to the cloth placing portion of the bed machine frame 3,
Further, a fixed knife 19 whose upper end is brought into close contact with the side surface of the needle plate 18 is fixed to a fixed knife table mounted on a part of the bed machine frame.

The movable knife 13 is brought into sliding contact with the fixed knife when the movable knife 13 is switched to the use state.

A presser foot 20 is detachably attached to the lower end of a presser bar supported on the sewing machine frame 1 substantially in parallel with the needle bar.

The cloth presser has a cloth presser portion 22 pivotally attached to a lower end of a mounting portion 21 attached to a lower end of a presser bar, and the cloth presser portion is a spring member 23.
The tip is urged to rotate downward by the action of and is stopped by the stopper.

A needle drop portion 25 through which a needle penetrates is formed in the cloth pressing portion, and a knife protection wall 24 and a cloth pressing claw 26 are formed on one side surface, and the cloth pressing claw is formed on the needle plate 18. The sewing cloth W is pressed on the claw portion 18 '.

At the intermediate portion between the knife protection wall 24 and the cloth pressing claw 24,
A hook-shaped guide 29 is integrally formed of a horizontal portion 27 extending from 22 to the fixed claw 19 side and a vertical portion 28 bent downward from the horizontal portion.

The vertical portion 28 is provided at a position on the cloth feeding side of the fixed knife 19, and is provided so as to have a gap G between the lateral direction and the side surface of the fixed knife 19, and the lower end surface is lower than the blade of the fixed knife 19 by L. It is provided.

FIG. 4 shows another embodiment, in which a hook-shaped guide 29 'is constructed separately from the cloth pressing portion 22 and a base end 30 is tightened with a screw.
It is fixed to the cloth pressing portion 22 at 31.

Since the present invention has the above-described structure, when the drive shaft 4 is rotated by the electric motor, the needle bar having the needle (N) is vertically reciprocated, and the upper looper 11 is synchronized with the vertical movement of the needle. Also, the lower looper 12 is swung to perform overedging.

When the movable knife 13 is used by the operating portion 17, the movable knife 13 cooperates with the fixed knife 19 to cut the sewing cloth W and perform overlock stitching on the edge of the sewing cloth.

In the released state of the movable knife 13, the movable knife has a movable knife shaft 15
Since it is rotated around and is separated from the fixed knife 19, the cooperative relationship with the fixed knife is released.

In many cases when the movable knife is desired to be released, pintuck sewing is performed, and in other than pintuck sewing, the movable knife is generally sewn in a cooperative relationship with the fixed knife.

According to the present invention, since the cloth presser foot 20 is provided with the hook-shaped guide portion 29, and the vertical portion 28 of the guide portion is arranged at the position on the cloth feeding side of the fixed knife 19, it is possible to use a movable knife. In the state, since it is outside the edge of the sewing cloth, it does not affect the sewing cloth.When the movable knife is released, the edge of the sewing cloth that spreads outside the fixed knife is bent upward at the vertical portion 28. It is possible to prevent the edge from falling into the hole on the side edge of the needle plate by guiding.

Therefore, it is possible to prevent the cloth edge from dropping downward from the gap on the side of the needle plate caused by the release of the movable knife even when the misused sewing machine in which the movable knife is in the released state is operated by mistake during other than pintuck sewing. .

(Effect) Since the present invention has the structure and operation as described above, the movable knife is released and the pintuck sewing is performed, and after the pintuck sewing is completed, the movable knife is forgotten to switch to the use state and is operated by mistake. However, since the fall of the edge of the sewing cloth below the needle plate is prevented, the looper piercing accident does not occur at all, and it is possible to prevent the phase shift of the looper shaft from occurring. It is possible to provide a safe sewing machine in which no accident occurs due to use, which is a great practical effect.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention, FIG. 1 is a partial sectional perspective view of a sewing machine equipped with the present invention, FIG. 2 is a perspective view of a main part of the present invention, and FIG. Partial sectional front view of the present invention,
FIG. 4 is a perspective view showing another embodiment of the present invention, and FIG. 5 is a view showing a conventional example, where 4 is a drive shaft, 11 and 12 are loopers, and 13 is a looper.
Is a movable knife, 18 is an operation part, 19 is a fixed knife, 20 is a presser foot,
27 is a horizontal part, 28 is a vertical part, 29 is a cloth end guide, F is a feed dog, N is a needle, and W is a sewing cloth.

Claims (1)

[Scope of utility model registration request] 1. A drive shaft rotatably supported by a sewing machine frame, a needle bar and a needle that can be moved up and down in association with the rotation of the drive shaft, and a sewing work in association with the rotation of the drive shaft. A feed dog for moving the cloth, a cloth presser attached to a presser bar of the sewing machine frame so as to be capable of being pressed against the feed dog, and a sewing machine which is rocked in conjunction with the rotation of the drive shaft and cooperates with the needle. Equipped with a looper that forms eyes and a lower type movable knife that is pivotally attached to a movable knife arm that is swingably supported by the bed machine frame and that cuts the sewing cloth in cooperation with a knife that is fixed to the machine frame side. In the overlock sewing machine, the movable knife is rotatably supported on the bed machine frame, and the operating state in which the movable knife cooperates with the fixed knife and the released state in which the cooperative relationship with the fixed knife is released. And a movable knife switching device that can be switched to With a cloth guide characterized in that a bent hanging part is brought close to the surface of the fixed knife, and a cloth presser equipped with a hook-shaped cloth end guide whose lower end is lower than the blade of the fixed knife is provided. Overlock sewing machine with a presser foot.