JPH06233879A - Darning method changing device for lock sewing machine - Google Patents

Abstract

PURPOSE:To prevent a failure of a sewing machine due to a thread at the time of idle sewing by providing a moving means moving a normal darning claw in the direction perpendicular to the fabric feed direction, separating it from a throat plate, then moving it to a nonaction position when the sewing method is changed from the normal over casting to the rolled seam. CONSTITUTION:When the sewing method is changed from the normal over costing to the rolled seam, a darning width adjusting knob 42 is rotated clockwise, then a cam 42a kept in contact with a control shaft 38 is changed from the center section in the circular arc direction to the end section in the circular arc direction of the cam section 42a. The end section of the circular arc of the cam section 42a is made shallower than the center section, the control shaft 38 is slid in the direction R, and the normal darning claw 14 is moved from an action position to the position of a dashed line. When the knob 42 is rotated in the same direction and a coupling section 50 is coupled with a protruded body 42b, the control shaft 38 is also rotated in the same direction, a fitting member 18b is moved obliquely downward via a link 34, the normal darning claw 14 is moved downward than the upper face of a throat plate 10, and it is set to the waiting state at a nonaction position unrelated with sewing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cloth rolled from a usual overlock stitch, in which an overlocking claw that cooperates with a needle and a looper is moved below a needle plate to overhang a flat cloth edge. The present invention relates to a lock sewing machine capable of changing a sewing method to a roll-stitched stitch.

[0002]

2. Description of the Related Art Conventionally, as such a lock sewing machine, there is a sewing machine described in Japanese Utility Model Publication No. 62-32551. In the sewing machine described in that publication, a roll stitching hook for roll stitching is formed on the right side of the needle plate. The upper surface of the rolled seaming nail and the upper surface of the needle plate are flush with each other. The winding stitch claw is configured to cooperate with the needle and the looper to perform the winding stitch.

Further, the normal overlocking nail for normal overlock stitching is constructed so as to perform normal overlocking stitch in cooperation with the needle, the looper and the winding stitch overlocking hook at an operating position juxtaposed with the winding overlocking hook. Has been done. When performing normal overlock stitching, the thread is entangled by the needle and the looper between the normal overlocking pawl and the roll stitching overlocking pawl at the working position, so that a seam is formed. Further, in the working position, the overlocking claw is normally configured to be movable in a direction substantially orthogonal to the cloth feeding direction, and the overlocking width of the normal overlock stitch is adjustable.

In order to perform the winding sewing, the overlocking claw is usually constructed so as to be linearly slidable from its working position to a non-working position that is not involved in sewing. The non-acting position is in the vicinity of the working position and is provided below the needle plate that does not interfere with the sewing work for the operator and does not hinder the operation of the sewing machine. Further, below the normal overlocking pawl located at the operating position, a movement space is defined for moving the normal overlocking pawl below the needle plate while avoiding contact with the needle plate. Further, even if the normal overlocking pawl is moved in a direction substantially orthogonal to the cloth feeding direction due to the change of the overlocking width, the width is such that the normal overlocking pawl can move below the needle plate from the operating position. Is in

Further, in such a lock sewing machine, even without a work cloth, threads are entangled with each other to form a stitch, and the stitch is constructed so as to allow empty stitches to proceed in the cloth feed direction. There is.

[0006]

However, in the conventional sewing machine, a sewing machine is usually provided below the operating position of the overlocking pawl.
Since the overlocking pawl normally defines a moving space having a movable width, the throat plate could not be projected below the operating position of the overlocking pawl, that is, near the needle drop point. Therefore, the thread associated with the empty stitch may fall into the sewing machine through the moving space, and the thread may be entangled with the mechanism inside the sewing machine, and the sewing machine may become inoperable.

The present invention has been made in order to solve the above-mentioned problems, and even if a needle plate is normally projected below the operating position of the overlocking pawl to prevent the thread from falling inside the sewing machine, When changing the sewing method from normal overlock stitch to roll stitch, by moving the normal overlock pawl for normal overlock stitch once to the right and then to the upstream side in the cloth feed direction, An object of the present invention is to provide an overlocking type converting device for a lock sewing machine, which is capable of moving an overlocking claw to an inoperative position below a plate.

[0008]

To achieve this object, the overlocking system conversion device for a lock sewing machine of the present invention, when changing the sewing method from normal overlock stitch to winding stitch,
Normally move the overlocking pawl to the right of the cloth feed direction,
A moving means for moving the normal overlocking pawl to the inoperative position after the normal overlocking pawl is separated from the needle plate is provided.

[0009]

In the overlocking type converting device for a lock sewing machine of the present invention having the above construction, the moving means normally separates the overlocking pawl from the needle plate, and the normal overlocking pawl is provided on the moving path from the operating position to the lower side of the needle plate. Moving. After that, the moving means moves the normal overlocking pawl below the upper surface of the needle plate, so that the normal overlocking pawl is not involved in sewing. Since the normal overlocking pawl moves from the position moved from the operating position to below the upper surface of the needle plate, the needle plate can be disposed below the normal overlocking pawl in the operating position.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The cloth feeding direction is the F direction, and the opposite direction is the B direction. When viewed from the operator in the direction orthogonal to the cloth feeding direction, the right direction is the R direction and the left direction is the L direction.

As shown in FIG. 1, an opening 10a for the needle drop point of a known sewing needle is formed in the needle plate 10. On the needle plate 10 on the F direction side of the opening 10a, an inclined surface portion 10b that is inclined downward from the upper surface of the needle plate 10 toward the opening 10a is formed. On the right end of the needle plate 10 on the B direction side of the opening 10a and on the R direction side of the needle drop point, a wound stitching hook 12 is fixed. The winding stitch claw 12 is formed so as to be oriented in the F direction. Further, the upper surface of the winding stitch caulking claw 12 and the upper surface of the needle plate 10 are on the same plane, and the tip of the winding stitch caulking claw 12 is located above the inclined surface portion 10b.

Further, the normal overlocking pawls 14 are arranged side by side on the R direction side of the winding stitch dragging claws 12, and the normal overlocking pawls 14 are formed so as to point in the same direction as the winding stitching dragging hooks 12. When the normal overlocking pawl 14 is juxtaposed with the winding sewing overlocking pawl 12 on the R direction side on the horizontal plane, one end 14a of the normal overlocking pawl 14 is located above the slope 10b. One end 1 of this normal overlocking claw 14
In 4a, a small taper with a narrowed tip in the F direction is formed on the outer side surface and the lower side surface on the R direction side so that the overlocking thread can be easily pulled out.

As shown in FIG. 2, the overlocking claw 14 is normally bent downward and extends downward of the needle plate 10. Normally, the positioning portion 14b is provided at the other end of the overlocking pawl 14.
Are formed. Positioning part 14 of the overlocking claw 14
b is engaged with the seat portion 18a of the mounting member 18. Further, the seat portion 18a and the other end of the normal overlocking pawl 14 are fixed by a screw 20.

As shown in FIG. 3, the seat portion 18a is a base portion 18a.
It projects from one end of b, and this base portion 18b defines a U shape when viewed in the F direction. The surface of the base portion 18b facing the surface of the base portion 18b from which the seat portion 18a projects is
A long groove 18c is formed obliquely so as to rise in the direction (see FIG. 2). The middle portion of the shaft 22 is inserted into the long groove 18c. One end of the shaft 22 is fixed to the sewing machine frame 26R with a screw 24, and a retaining ring 28 is fixed to the other end of the shaft 22.

Both ends of a shaft 30 parallel to the shaft 22 are rotatably supported on the two opposing surfaces of the base portion 18b, and retaining rings 32 are provided at both ends of the shaft 30 to prevent the shaft 30 from coming off. It is fixed. One end of a link 34 is fixed to the shaft 30 with a screw 36 at an intermediate portion of the shaft 30. To the other end of the link 34, one end of a control shaft 38 parallel to the shaft 30 is fixed by a screw 40. The middle portion of the control shaft 38 is slidably and rotatably supported by the sewing machine frame 26R.

When the control shaft 38 slides, the mounting member 18 moves together with the control shaft 38 via the link 34. Further, when the control shaft 38 is rotated, the attachment member 18 is moved through the link 34 so that the attachment member 18 is elongated.
It is configured to move up and down diagonally along c.

As shown in FIG. 1, the other end of the control shaft 38 is
It is in contact with a groove-shaped cam portion 42a formed on one surface of the overedging width adjusting knob 42. The overedging width adjusting knob 42 has a disk shape, and its center is rotatably supported by the sewing machine frame 26L by a shaft 44. Further, the overedging width adjusting knob 42 is configured to be rotatable by an operator. The shaft 44 is fixed to the sewing machine frame 26L by screws 46.

The overall planar shape of the cam portion 42a defines an arc centered on the shaft 44. The cam portion 42a is formed so as to be deepest from the surface of one surface of the overedging width adjusting knob 42 at the center of the arc, and gradually become shallower toward the end of the arc in the arc direction. Cam portion 4 shown in FIG.
The end of the arc located above 2a is formed shallower than the end of the arc located below cam 45a. Therefore, the control shaft 38 is configured to slide in the LR direction with the rotation of the overlock width adjusting knob 42.

Further, when the other end of the control shaft 38 comes into contact with the end of the arc of the cam portion 42a located in the lower side in FIG. 2, the overedging width of the normal overlock stitch is maximum, and the arc of the cam portion 42a is the maximum. When the other end of the control shaft 38 comes into contact with the central portion, the overedging width of the usual overedging is configured to be the minimum. When the other end of the control shaft 38 comes into contact with the end of the circular arc located above the cam portion 42a, one end 14a of the overlocking pawl 14 normally moves to the right side of the throat plate 10 as shown by the alternate long and short dash line in FIG. In this case, the needle plate 10 is not provided below the one end 14a of the overlocking claw 14 and a space communicating with the inside of the sewing machine is defined.

Further, a spring 48 is inserted through the control shaft 38 on the L direction side of the sewing machine frame 26R so that the sewing machine frame 26R can be pressed. Further, one end of a guide plate 50 is fixed to the control shaft 38 by a screw 52 so that a spring 48 can be pressed against the control shaft 38. Therefore, the control shaft 38 is controlled by the spring 48.
Is always in contact with the cam portion 42a.
At the other end of the guide plate 50, the overedging width adjustment knob 42
Engaging portion 50a that engages with the protrusion 42b that is erected on one surface
Is molded. Therefore, the control shaft 38 is configured to rotate via the guide plate 50 as the overedging width adjusting knob 42 rotates. A spring 54 is hooked between the sewing machine frame (not shown) and the other end of the guide plate 50, and the mounting member 18 is moved to the control shaft 38 in the state shown in FIGS.
Is configured to be located through.

As shown in FIG. 6, the overedging width adjusting knob 4
A groove-shaped guide portion 42d is formed on the other surface side of 2. The overall planar shape of the guide portion 42d is an arc centered on the shaft 44. Stoppers 42e and 42f are formed at the ends of the arc of the guide portion 42d.

As shown in FIG. 1, one end 56a of a stopper shaft 56 is located inside the guide portion 42d, and the stopper shaft 56 is screwed to the sewing machine frame 26L by a nut 58. One end 56a of the stopper shaft 56 is eccentric with respect to a portion 56b screwed to the sewing machine frame 26L and is thick. One end 56 of this stopper shaft 56
By contacting the stoppers 42e and 42f of the guide portion 42d with a, the rotation range of the overedging width adjusting knob 42 is regulated.

Next, the normal overlocking claw 14 is moved to the operating position (see FIG. 1).
2) and an operation position (see FIG. 5) below the upper surface of the needle plate 10 will be described.

First, the overedging width adjusting knob 42 shown in FIG.
When is rotated in the Q direction by the operator, the cam portion 42a that contacts the control shaft 38 changes from the central portion in the arc direction to the end portion of the cam portion 42a in the arc direction. Cam part 25a
Since the end of the arc is shallower than the central part, the control shaft 38 slides in the R direction, and the overlocking claw 14 normally moves from the operating position to the position indicated by the alternate long and short dash line in FIG. That is, the normal overlocking pawl 14 moves to a position below which the needle plate 10 does not exist, and the normal overlocking pawl 14 can move downward.

Further, when the overedging width adjusting knob 42 is further rotated in the Q direction and the engaging portion 50a is engaged with the protrusion 42b, the control shaft 38 is also rotated in the Q direction. And the control axis 3
8 moves the mounting member 18 obliquely downward from the position shown in FIG. 4 to the position shown in FIG.
Therefore, the overlocking nail 14 normally waits in an inoperative position where it is not involved in sewing, and winding sewing becomes possible. At this time, one end 56a of the stopper shaft 56 is connected to the stopper 42 of the guide portion 42d.
The width adjusting knob 42 is regulated so as not to rotate any more by coming into contact with f.

As described above, when the normal overlocking pawl 14 is moved from the working position to the non-working position, it is moved in the R direction, which is perpendicular to the cloth feeding direction F and is on the right side of the cloth feeding direction, to make contact with the needle plate 10. Since the needle plate 10 is moved to the inoperative position after the avoidance, the needle plate 10 can be extended longer than the conventional one toward the needle drop point.

In addition, the entanglement of the thread extending over the normal overlocking claw 14 and the winding stitch overlocking claw 12 is spread to some extent by pulling it along with the normal overlock stitch, so that the normal overlocking claw 14 with the thread entangled below it. It is possible to move in the R direction to a position where the needle plate 10 is not present. Then, after the normal over pawl 14 is moved in the R direction, the normal over pawl 14 is moved.
Is moved in the B direction, and the thread entwined with the overlocking claw 14 is normally removed. Therefore, since the normal overlocking claw 14 in which the thread is entangled can be moved from the operating position to the inactive position, the time and effort for cutting the entangled thread over the normal overlocking claw 14 and the winding stitch dragging claw 12 is eliminated. .

Further, since the overlocking pawl 14 is normally moved downward from the upper surface of the needle plate 10 from the fixed position moved by the cam portion 42a, the space for moving it downward can be narrowed. Therefore, it becomes difficult for fine threads or cloths to enter the inside of the sewing machine, so that the frequency of removing them from the inside of the sewing machine is reduced and the labor of maintenance is reduced. Since the opening for descending is formed on the right side of the needle plate 10 and the opening 10a near the needle drop point can be made small, it is possible to prevent the thread from falling inside the sewing machine. In the present embodiment, the change in the sewing method and the change in the width of the normal overedging can be performed with the same part, which leads to a reduction in the number of parts and cost.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

Ordinarily, the overlocking pawl 14 and the mounting member 18 may be integrally formed. Further, the spring 48 and the spring 54 can be operated by one spring by utilizing the compressibility and the torsion recovery of the spring. Further, in the present embodiment, the overedging width adjusting knob 42 is configured to be rotated by an operator, but may be configured to be rotated by a pulse motor or the like.

[0031]

As is apparent from the above description, according to the overlocking type converting device for a lock sewing machine of the present invention, since the throat plate can be extended in the direction of the needle drop point for a long time, the thread accompanying the empty stitching can be increased. It is prevented that small foreign objects fall into the sewing machine below the needle plate. Therefore, a failure of the mechanism inside the sewing machine due to the thread or foreign matter is unlikely to occur, the sewing method can be changed and the sewing work can be favorably performed, and the production efficiency is improved.

[Brief description of drawings]

FIG. 1 is a plan view of a normal overlocking claw in an operating position according to an embodiment of the present invention.

FIG. 2 is a right side view of FIG.

FIG. 3 is a front view of FIG. 1.

4 is a partially cutaway right side view of FIG. 2. FIG.

FIG. 5 is a partially cutaway right side view when the normal overlocking pawl is in the inoperative position in one embodiment of the present invention.

FIG. 6 is a left side view of FIG. 1.

[Explanation of symbols]

 10 Needle plate 10b Sloping surface part 12 Rolling stitching claw 14 Normal overlocking claw 18c Long groove 34 Link 38 Control shaft 42 Overlocking width adjustment knob 42a Cam part 42b Projection body 50 Guide plate 50a Engagement part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Wakayama 15-1 Naeshiro-cho, Mizuho-ku, Nagoya City Brother Industries, Ltd.

Claims (1)

[Claims] 1. A wound-up sewn claw which is fixed to the right side of a throat plate in the cloth feeding direction and cooperates with a needle and a looper to bend over a side end of a work cloth to fold and sew. In a working position located in parallel with the roll stitching hook, the needle and the looper and the roll stitching hook are cooperated with each other to perform a normal overlock stitch in which the side end of the work cloth is flattened. A lock sewing machine having a normal overlock pawl that is movable from the operating position to an inactive position below the upper surface of the needle plate, when changing the sewing method from the normal overlock stitch to the roll stitch A moving unit that moves the normal overlocking pawl to the right with respect to the cloth feeding direction to move the normal overlocking pawl away from the needle plate and then moves the normal overlocking pawl to the inoperative position. Is it a characteristic lock sewing machine? Ri system conversion apparatus.