JPH06327871A - Upper knife release device for overlook machine - Google Patents

Abstract

PURPOSE:To provide an upper release device which is safe and which can enlarge an operating space during double ring sewing or special sewing. CONSTITUTION:In an overlook machine which carries out edge overlook sewing and at least one kind of sewing other than overlook sewing, and having an upper knife swinging arm 16 to which an upper knife for cutting a cloth is attached, an upper knife drive means 26 for vertically swinging the upper knife swinging arm 16, and an upper knife release and holding plate 44 fixed to a machine frame above the upper knife drive means, the upper knife swing arm is coupled to the upper knife drive means when sewing is carried out with the use of the upper knife. Further, a change-over device 40 secures the upper knife swinging arm to the upper knife release hold plate when sewing is carried out with no use of the knife.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an upper knife releasing device for an overlock sewing machine, and more particularly to an upper knife releasing device for an overlock sewing machine which performs overedging, double ring and special sewing.

[0002]

2. Description of the Related Art When overedge sewing is performed by an overlock sewing machine, the sewing is performed while the cloth is being cut by sliding the upper knife and the lower knife. It is known that an upper knife is supported by a moving member, and the upper knife swinging member is driven up and down by an upper knife driving means using a main shaft of a sewing machine as a driving source.

By the way, when overedging with cloth cutting is performed,
When using an overlock sewing machine that can perform both double chain stitching and special stitching without cloth cutting, it is necessary to make cloth cutting by the upper knife ineffective when performing double chain stitching and special sewing. is there.

For this reason, conventionally, the upper knife swinging member is rotatably supported at an acting position acting on the lower knife and an inoperative position separated from the upper knife, and the upper knife swinging member is rotatably supported at the time of double chain stitching and special sewing. The knife is rotationally locked to the inoperative position.

[0005]

In the above prior art, since the upper knife swinging member remains rotated even if the upper knife is separated from the lower knife by rotating the upper knife with respect to the upper knife swinging member. However, it is dangerous when working on the sewing machine table, and the upper knife swinging member obstructs the work space.

Therefore, an object of the present invention is to provide an upper knife release device which is safe and can widen the working space when performing double chain stitching and special stitching.

[0007]

In order to achieve the above object, an upper knife release device according to the present invention is used for cutting cloth in an overlock sewing machine which performs overedging and at least one type of sewing other than overedging. An upper knife swing arm having a knife attached thereto, an upper knife drive means for vertically swinging the upper knife swing arm, and an upper knife release holding plate fixed to a sewing machine frame above the upper knife drive means. ,
A switching device that connects the upper knife swing arm to the upper knife driving means when sewing using a knife and fixes the upper knife swing arm to the upper knife release holding plate when sewing without using a knife. It is characterized by having.

The overlock sewing machine has an exterior,
It is preferable that the switching device is provided outside the exterior.

For example, the upper knife release device includes a connecting pin, elastic means for urging the connecting pin in a direction away from the upper knife swing arm, and the connecting pin for restraining the upper knife swing arm. The upper knife drive shaft and the upper knife release holding plate each have a fitting hole capable of fitting with the connecting pin, and the connecting pin is used when sewing using a knife. Is connected to the fitting hole of the upper knife driving means to connect the upper knife swinging arm to the upper knife driving means, and the connecting pin is fitted to the upper knife release holding plate when sewing without using a knife. The upper knife swing arm is fitted into the hole and fixed to the upper knife release holding plate.

Further, for example, in the upper knife release device according to claim 2, the upper knife drive shaft has an inclined surface and a stopper for restraining the downward movement of the connecting pin, and the upper knife release holding plate has an inclined surface. A stopper for preventing upward movement of the connecting pin, and when sewing using a knife, the connecting pin moves downward until it comes into contact with the stopper while sliding on the inclined surface of the upper knife driving means. When the sewing is performed without using a knife, the connecting pin slides up the inclined surface of the upper knife release holding plate and moves upward until it comes into contact with the stopper. Is fitted to.

[0011]

When sewing using a knife, the upper knife swing arm is connected to the upper knife drive means by the switching device, and the upper knife swing arm can be vertically swung by the upper knife drive means.

When sewing without using a knife, the upper knife swing arm is fixed to the upper knife release holding plate by the switching device to release the connection with the upper knife driving means. Since the upper knife release holding plate is fixed to the sewing machine frame above the upper knife driving means, the upper knife swing arm is fixed above, and when performing double chain stitching and special sewing without using a knife. Safe and wide working space.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an upper knife release device of an overlock sewing machine of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an entire overlock sewing machine suitable for applying the upper knife release device according to this embodiment. The overlock sewing machine 2 includes an arm 4 and a bed 6. The arm 4 has one or two needles 8,1
0 is provided so as to be vertically movable, and a needle plate 12 is provided on the bed so as to be located below the needles 8 and 10. An upper knife swinging arm 16 of an upper knife release device, which will be described later, is provided so as to project from the exterior 14 of the overlock sewing machine in the direction of the bed 6.

FIG. 2 is an exploded perspective view of the upper knife release device according to this embodiment, and FIG. 3 is a top view of FIG.

In these figures, an upper knife drive cam 20 is fixed to the main shaft 18, and this upper knife drive cam 20 is fixed.
The bifurcated portion of the tip of the upper knife drive arm 22 is engaged. Upper knife swing shaft 24 extending parallel to the main shaft 18
Of the sewing machine protrudes from the inside of the exterior 14 (see FIGS. 1 and 3) of the sewing machine to the outside. Inside the outer casing 14, an upper knife driving plate 26 is rotatably attached to the upper knife swing shaft 24 at one end thereof.

One end of the upper knife driving plate 26 is fixed to the upper knife driving arm 22 by a set screw 28. Further, near the other end of the upper knife drive plate 26, the inclined surface 26a,
A tip hole portion 26b and a stopper 26c are formed.

An upper knife swing arm 16 is rotatably attached at one end thereof to a portion of the upper knife swing shaft 24 protruding to the outside of the outer casing 14 of the sewing machine.

The upper knife swing shaft 24 is connected to the frame 3 through the metal 30, 30 mounted between the upper knife swing arm 16 and the upper knife drive plate 26 and to the right of the upper knife drive plate 26.
It is fixed at 2. Further, the upper knife swing shaft 24 is provided with a retaining ring 34 for stopping the upper knife swing arm 16 in the thrust direction.

An upper knife 38 rotatable by an upper knife rotating means 36 and a switching device 40 are provided near the other end of the upper knife swing arm 16. The switching device 40 is for driving the upper knife swing arm 16 or stopping it at an upper position, as described later.

The upper knife drive plate 26 is fixedly mounted on the upper knife drive arm 22 so that the vertical position of the tip of the upper knife drive plate 26 can be adjusted slightly in order to adjust the motion phase of the upper knife swing arm 16. It is adjustable.

An upper knife release holding plate 44 is fixed to the frame 32 inside the sewing machine with screws 42. The upper knife release holding plate 44 has an inclined surface 44a, a stopper portion 44c and a hole 44b.

Next, the structure of the switching device 40 will be described with reference to FIG. 4. The spindle 1 is located near the tip of the upper knife swing arm 16.
A fitting hole 46 extending in the direction of 8 is formed, and in this fitting hole 46, a connecting pin 48 and an operating spring 50 for urging the connecting pin 48 in the direction of arrow B are incorporated. An elongated hole 52 communicating with the fitting hole 46 is formed at the tip of the upper knife swing arm 16. The connecting pin 48 is formed with a screw hole 54 on its peripheral surface.

A screw guide plate 58 having an elongated hole 56 is fixed to the upper knife swing arm 16 by screws 60, 60, and a connecting pin tightening screw 62 is provided on the elongated hole 56 and the upper knife swing arm 16.
Through the long hole 52 of the above and engages with the screw hole 54 of the connecting pin 48. A retaining ring 64 is interposed between the upper knife swing arm 16 and the screw guide plate 58. By passing the connecting pin tightening screw 62 through the retaining ring 64, the connecting pin 48 can be loosened even if the connecting pin tightening screw 62 is loosened. The screwing with the screw hole 54 is prevented from being released. Therefore, the connecting pin tightening screw 6
When 2 is tightened, the connecting pin 48 is fixed to the upper female swing arm 16, and when the connecting pin tightening screw 62 is loosened,
The connecting pin 48 is movable rightward together with the connecting pin tightening screw 62.

FIG. 5 is a partial front sectional view of this embodiment.
FIG. 5A shows the state when the upper knife is driven, and FIG. 5B shows the state when the upper knife is released. 6 and 7 are oblique views showing the main part of the sewing machine incorporating this embodiment. FIG. 6 shows the state when the upper knife is driven, and FIG. 7 shows the state when the upper knife is released. As shown in these figures, the outer casing 14 has an arc-shaped guide groove 6
6 is formed, and the tip end portion of the connecting pin 48 is fitted into the guide groove 66. In FIG. 7, reference numeral 68 indicates an auxiliary bed.

At the time of overedging, the upper knife is driven as shown in FIGS. 5 (A) and 6, but in this state, first, the connecting pin tightening screw 62 is loosened, and the connecting pin 4 is sewn.
After moving 8 in the direction of arrow A to separate it from the hole 44b of the upper knife release holding plate 44, the upper knife swing arm 16 is rotated clockwise (direction D in FIG. 6). At this time, the connecting pin 48
Moves downward along the inclined surface 26a of the upper knife drive plate 26 while sliding, and contacts the stopper 26c to stop the downward movement, and moves in the B direction by the operating spring 50. Then, it is fitted into the tip hole portion 26b. After being fitted in this way, when the connecting pin tightening screw 62 is tightened, the upper knife swing arm 16 and the upper knife drive plate 26 can be integrally swung in the vertical direction. At this time, upper swing arm 1
The moving range of the connecting pin 48 that moves up and down together with 6 is indicated by reference symbols a and b in the guide groove 66. Upper knife rotating means 36
When the upper knife 38 is rotated to the position shown in FIG. 6 and set on the lower knife 70, the cloth edge is cut by sliding between the upper knife 38 and the lower knife 70 mounted on the side surface of the needle plate 12.

At the time of double ring and special sewing which does not require cloth cutting, the upper knife is released as shown in FIGS. 5 (B) and 7, but in order to bring this state, first, the connecting pin tightening screw is used. 62 is loosened, the connecting pin 48 is moved in the direction of arrow A to be disengaged from the tip hole portion 26b of the upper knife driving plate 26, and the upper knife swing arm 16 is rotated counterclockwise (direction C in FIG. 7). Then, the connecting pin 48 moves to the position indicated by the reference numeral c in the guide groove 66. At this time, the connecting pin 48 is connected to the inclined surface 4 of the upper female release holding plate 44 provided on the frame 32.
4a ascending while sliding along the inclined surface and abutting against the stopper portion 44c to stop the ascending, and the operating spring 5
0 moves in the direction of arrow B and is fitted into the hole 44b. By tightening the connecting pin tightening screw 62, it is reliably held in a stopped state above the auxiliary bed 68.
Before loosening the connecting pin tightening screw 62, it is preferable to rotate the upper knife 38 in the C direction and release it to the position shown in FIG. 7 in advance.

Since the upper knife device is held at the position above the auxiliary bed 68 in this manner, there is no risk of an operator touching the upper knife 38 when working on the auxiliary bed 68, and moreover, the auxiliary bed 68. Since the distance between the upper knife swing arm 16 and the upper knife swing arm 16 can be increased, workability is improved.

Since this embodiment has the above-mentioned configuration,
Regardless of the position of the vertical movement phase of the upper knife swing arm 16, the upper knife swing arm 1 can be easily moved from the outside of the exterior 14.
6 can be mounted and released.

[0030]

According to the upper knife release device of the present invention,
When performing double chain stitching and special sewing without using a knife, the switching device is used to fix the upper knife swing arm to the upper knife release holding plate above the upper knife driving means and connect it with the upper knife driving means. Since it is released, it is safe and the working space can be widened.

[Brief description of drawings]

FIG. 1 is a perspective view showing an entire overlock sewing machine suitable for applying an upper knife release device according to this embodiment.

FIG. 2 is an exploded perspective view of the upper knife release device according to the present embodiment.

FIG. 3 is a top view of FIG.

4 is a partially enlarged exploded perspective view of FIG.

5 is a partial front sectional view of the present embodiment, and FIG.
Shows the state when the upper knife is driven, and FIG. 5B shows the state when the upper knife is released.

FIG. 6 is a perspective view showing a main part of a sewing machine incorporating this embodiment, showing a state when an upper knife is driven.

FIG. 7 is a perspective view showing the main part of the sewing machine incorporating the present embodiment, showing the state when the upper knife is released.

[Explanation of symbols]

 2 Overlock sewing machine 4 Arm 6 Bed 8, 10 needles 12 Needle plate 14 Exterior 16 Upper knife swing arm 18 Spindle 20 Upper knife drive cam 22 Upper knife drive arm 24 Upper knife swing shaft 26 Upper knife drive plate 26a Sloping surface 26b Tip hole 26c Stopper 28 Set screw 30, 30 Metal 32 Frame 34 Stop ring 36 Upper knife rotating means 38 Upper knife 40 Switching device 42 Screw 44 Upper knife release holding plate 44a Inclined surface 44b Hole 44c Stopper part 46 Fitting hole 48 Connection Pin 50 Operating spring 52 Long hole 54 Screw hole 56 Long hole 58 Screw guide plate 60,60 Screw 62 Connecting pin tightening screw 64 Snap ring 66 Guide groove 68 Auxiliary bed 70 Lower female

Claims (4)

[Claims] 1. An overlock sewing machine that performs at least one type of sewing other than overedging and overedging, and an upper knife swinging arm to which an upper knife for cloth cutting is attached, and the upper knife swinging arm is moved up and down. The upper knife driving means swinging to the upper knife, the upper knife release holding plate fixed to the sewing machine frame above the upper knife driving means, and the upper knife swinging arm to the upper knife driving means when sewing using a knife. And a switching device for fixing the upper knife swing arm to the upper knife release holding plate during sewing without using a knife. 2. The upper knife release device according to claim 1, wherein the overlock sewing machine has an exterior, and the switching device is provided outside the exterior. 3. The upper knife release device according to claim 1, wherein the upper knife release device comprises a connecting pin,
An elastic means for urging the connecting pin in a direction away from the upper knife swinging arm; and a restraining means for restraining the connecting pin with respect to the upper knife swinging arm and releasing the restraint. The knife drive shaft and the upper knife release holding plate each have a fitting hole capable of fitting with the connecting pin, and when sewing using a knife, the connecting pin is fitted into the fitting hole of the upper knife driving means. The upper knife swinging arm to the upper knife driving means, and when sewing without using a knife, the connecting pin is fitted into the fitting hole of the upper knife release holding plate to move the upper knife swinging arm. Upper knife release device characterized by being fixed to the upper knife release holding plate. 4. The upper knife release device according to claim 3, wherein the upper knife drive shaft has an inclined surface and a stopper for stopping downward movement of the connecting pin, and the upper knife release holding plate has an inclined surface. When the sewing machine uses a knife, the connecting pin slides down the inclined surface of the upper knife driving means and moves downward until it comes into contact with the stopper. When sewing without using a knife, the connecting pin slides up the inclined surface of the upper knife release holding plate and moves upward until it comes into contact with the stopper, and is inserted into the fitting hole. Upper knife release device characterized by being fitted.