JP2744192B2 - Two-needle sewing machine thread cutting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thread cutting device for a two-needle sewing machine, and more particularly, to an operation for easily adjusting the positions of first and second moving knives accompanying adjustment of the needle width of two sewing needles. The present invention relates to a thread cutting device for a two-needle sewing machine that can be operated quickly.

[0002]

2. Description of the Related Art As shown in FIG. 4, two sewing needles N1, N
The two-needle sewing machine M provided with the rotary hooks 2 includes rotary hooks (horizontal rotary hooks) A1 and A2 below the sewing needles, and the rotary hooks capture the upper thread held by each sewing needle. By intersecting with the lower thread, two seams (not shown) parallel to the sewing object can be formed. The two-needle sewing machine M can change the width of the needle, that is, the width of the stitch formation, equally by changing the needle stopper member Na for fixing the sewing needles N1 and N2.

When the needle width is changed by exchanging the needle stopper member Na, it is necessary to change the positions of the rotary hooks A1 and A2, which form the seam by the sewing needles N1 and N2. Also, when the positions of the rotary hooks A1 and A2 are changed as described above, it is necessary to adjust the position of the thread cutting device of the sewing machine that cuts each sewing thread between each sewing needle and the rotary hook at the end of sewing. is there.

FIG. 5 is a diagram showing a thread cutting device for a two-needle sewing machine. In the drawing, B1 and B2 are rotary hook bases respectively supporting rotary hooks A1 and A2.
B2 can be approached to and separated from each other.
1, the distance between A2 can be adjusted. C1 is a first moving knife, C2 is a second moving knife, and the first and second moving knifes C1, C2
Is rotatably supported by the female support tables 1 and 2 installed on the rotary hook tables B1 and B2.

Reference numeral 3 denotes a connecting lever for connecting the female supports 1 and 2 to each other. The connecting lever 3 has two connecting members 3a and 3b having elongated holes opposed to each other, and fixes these members. And a fixing nut (not shown) that is screwed to the fixing screw 8 on the back surface of the connecting lever 3 so that the overlapping length of the connecting members 3a and 3b can be adjusted. By changing the length, the total length of the connecting lever 3 can be adjusted.

On the other hand, reference numeral 4 denotes a knife driving means, which is connected to the lower shaft 10 of the sewing machine in response to a thread cutting signal at the time of completion of sewing, and rotates the arm 9 one reciprocation as shown by the arrow. You can move. And one
Reference numeral 1 denotes a joint rod as a connecting means for connecting the arm 9 of the knife driving means 4 and the knife support 2, and the joint rod 11 includes a screw rod 11a and the screw rod 1
Screw receiving rod 11 having nuts screwed on both sides of 1a
b, 11c. The total length of the joint rod 11 can be adjusted by rotating the nuts of the screw receiving rods 11b, 11c.

[0007] In the thread cutting device of the two-needle sewing machine having the above structure, when the thread cutting signal is received, the knife driving means 4 rotates the arm 9 counterclockwise and moves the joint rod 11 downward in the figure. Then, the female support 2 is rotated clockwise. Then, by the rotation of the knife support 2, the knife support 1 is rotated clockwise through the connecting lever 3, and the first and second moving knifes C1 fixed to the knife supports 1, 2 are rotated. , C2 are moved in the directions of the rotary hooks A1, A2, and the first and second moving knives C1, C2 capture respective sewing threads (not shown) between the sewing needles and the rotary hook.

Next, when the knife driving means 4 rotates clockwise and returns to the original position, the first and second moving knifes C
1 and C2 also return to their original positions (positions shown in the figure), and during this return movement, the sewing thread can be cut with a fixed knife (not shown).

Next, an adjusting operation for changing the needle width in the thread cutting device of the sewing machine will be described. When the position of the rotary hook bases B1 and B2 is adjusted to change the distance between the rotary hooks A1 and A2 according to the change of the needle width of the sewing machine, the total length of the connecting lever 3 and the joint rod 11 must be adjusted. There is. That is, if the positions of the rotary hook tables B1 and B2 are adjusted, the first and second moving knives C installed on these are adjusted.
The distance between the first and second moving knives C1 and C2 and the connecting lever 3 (the angles X and Y) also change. As a result, the rotation paths of the first and second moving knives C1 and C2 deviate from the sewing thread, and the two moving knives C1 and C2 do not cut the sewing thread. For this reason, it is necessary to adjust the positional relationship between the first and second moving knives C1 and C2 and the connecting lever 3 by expanding and contracting the connecting lever 3 in accordance with the position adjustment of the rotary hook bases B1 and B2.

On the other hand, when the position of the rotary hook base B2 changes so as to approach or separate from the knife driving means 4 by adjusting the positions of the rotary hook bases B1 and B2, the distance W between the knife support base 2 and the driving means 4 also changes. Will do. That is, since the joint rod 11 rotatable about the arm 9 of the knife driving means 4 cannot be moved in the horizontal direction in the figure together with the knife support 2, the overall length of the joint rod 11 is also adjusted. There is a need.

[0011]

The thread cutting device of the above-mentioned conventional two-needle sewing machine has the following problems and causes a reduction in work efficiency. That is, when performing the position adjustment in accordance with the change of the needle width of the sewing machine, in the conventional thread cutting device of the twin needle sewing machine, it is necessary to adjust the expansion and contraction of the connecting lever 3 and also to adjust the expansion and contraction of the joint rod 11. In particular, when adjusting the joint rod 11, the connection screw 11d connecting the female support base 2 and the joint rod 11 is removed, and the connection state between the joint rod 11 and the female support base 2 is released. Complicated work was forced.

[0012]

A thread cutting device for a two-needle sewing machine according to the present invention reciprocates on a rotary hook base provided below each of two sewing needles, and moves between the sewing needle and the rotary hook. First and second moving scalpels for capturing and cutting a sewing needle;
A connecting lever that connects the respective female support bases rotatably supporting the first and second moving knives and is capable of adjusting the expansion and contraction according to a change in the position of the rotary hook, and a lower shaft of the sewing machine at the end of sewing. Knife driving means for making one reciprocating rotation, and first and second
A connecting means for connecting any one of the scalpel supports of the moving knife and the scalpel driving means, wherein the connecting means is any one of a first moving knife and a second moving knife. A rotating member provided to be rotatable about a rotating shaft of one of the moving knives, and a turning position of the rotating member can be adjusted with respect to a support base of one of the moving knives provided with the rotating member. And a connection link that supports one end of the driving member and the other end of the rotating member.

[0013]

The thread cutting device for a two-needle sewing machine according to the present invention comprises:
When the position is adjusted in accordance with the change of the needle width of the sewing machine, the fixing means for fixing the knife support and the rotating member is released, and the connecting link connected to the knife driving means and the rotating member When the connection state is released, the connection lever connecting both the female support bases can be extended and contracted. Then, after adjusting the interval of the rotary hook base and fixing, the connecting lever is adjusted, and the rotating member and the female support base are fixed by the fixing means, so that the female driving means and the rotary member of the connecting link are connected. Thus, a predetermined thread cutting operation can be performed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The same parts as in the prior art are denoted by the same reference numerals, and redundant description will be omitted. FIG. 1 is a diagram showing a thread cutting device for a two-needle sewing machine according to the present invention. In the figure, D is a connecting means for connecting the knife driving means 4 and the knife support 2, and this connecting means D is provided rotatably about a rotation axis P of the second moving knife C2. A rotating member 7, fixing means 20 for fixing the rotating member 7 to the female support base 2,
And a connecting link 6 for connecting the rotating member 7 and the arm 9 of the knife driving means 4.

In this embodiment, the fixing means 20 comprises a fixing screw installed on the female support table 2,
The fixing screw 20 is inserted into an arc-shaped long hole 7a formed in the rotating member 7, and when screwed into the female support 2, the rotating member 7 is pressed against the female support 2 to fix them. You can do it.

Next, the operation of the thread cutting device for a two-needle sewing machine provided with the connecting means D will be described. Upon receiving the thread cutting signal, the knife driving means 4 rotates the arm 9 counterclockwise,
By moving the connecting link 6 downward in the figure, the rotating member 7 and the female support 2 fixed thereto are rotated clockwise. Then, by the rotation of the knife support 2, the knife support 1 is rotated clockwise through the connecting lever 3, and the first and second moving knifes C1 fixed to the knife supports 1, 2 are rotated. , C2 are moved in the directions of the rotary hooks A1 and A2 to capture the sewing thread (not shown) between each sewing needle and the rotary hook. Next, when the knife driving means 4 rotates clockwise and returns to the original position, the first and second moving knives C1 and C2 also return to the original positions (the positions shown in the drawing). The sewing thread can be cut with the fixed knife shown in the drawing.

Next, an adjusting operation for changing the needle width in the thread cutting device of the sewing machine will be described. When adjusting the position of the rotary hook bases B1 and B2 to change the distance between the rotary hooks A1 and A2 according to the change of the needle width of the sewing machine, first, the fixing screw 20 of the connecting means D is loosened, and the rotation is performed. The connection state between the member 7 and the female support 2 is released. That is, the rotating member 7 and the connecting link 6 are not moved even when the female support 2 is rotated in any direction. Then, in this state, the expansion and contraction of the connecting lever 3 is adjusted according to the approach and separation of the rotary hooks B1 and B2.

Next, after the connection lever 3 is adjusted, the rotating member 7 and the female support 2 are fixed by the fixing screw 20, and the female support 2 and the connecting link 6 are connected, in other words, the two needles. The thread cutting device of the sewing machine is set in a drivable state. When the connection between the knife support 2 and the connection link 6 is completed, for example, when the connection lever 3 is reduced and the knife support 2 is separated from the knife driving means 4,
As shown in FIG. 2, the rotating member 7 is fixed to the knife support 2 while being rotated clockwise about the rotating axis P. On the other hand, when the connecting lever 3 is extended to bring the knife support 2 close to the knife driving means 4, the rotating member 7 rotates counterclockwise about the rotating shaft P as shown in FIG. It is fixed to the knife support 2 in the moved state.

That is, the thread cutting device of the two-needle sewing machine provided with the connecting means D can easily perform the complicated expansion and contraction adjustment work of the conventional connecting means (joint rod 11) by the simple fixing screw 2
It can be replaced by a screwing operation of 0, and the adjusting operation efficiency of the thread cutting device of the two-needle sewing machine can be improved.

[0020]

The thread cutting device for a two-needle sewing machine according to the present invention reciprocates on a rotary hook base provided below each of the two sewing needles to catch a sewing thread between the sewing needle and the rotary hook. Connecting lever that connects first and second moving knives to be cut and cut, and each knife support that rotatably supports the first and second moving knives, and that can be extended and contracted according to a change in the position of the rotary hook When,
At the end of sewing, knife driving means connected to the lower shaft of the sewing machine to make one reciprocating rotation, connecting means for connecting any one of the first and second moving knives to the female support base and the female driving means, In the thread cutting device for a two-needle sewing machine provided with: a rotating member provided so as to be rotatable around a rotating shaft of one of the first and second moving knives; Fixing means for fixing the rotating member to the supporting table of one moving knife provided with the rotating member so as to adjust the rotating position, one end to the driving means and the other end to the rotating member, respectively. With the connecting link that supports the shaft, the two-needle sewing machine can be adjusted easily and quickly after adjusting the needle width, and the adjustment work can be performed easily and quickly. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a thread cutting device for a two-needle sewing machine according to the present invention.

FIG. 2 is a front view showing a state of the connecting means when the connecting lever is reduced in the thread cutting device of the two-needle sewing machine shown in FIG. 1;

FIG. 3 is a front view showing the state of the connecting means when the connecting lever is extended in the thread cutting device of the two-needle sewing machine shown in FIG. 1;

FIG. 4 is a front view showing a two-needle sewing machine.

FIG. 5 is a front view showing a conventional thread cutting device installed on a two-needle sewing machine.

[Explanation of symbols]

 D Connecting means C1 First moving knife C2 Second moving knife 1 Female support base 2 Female support base 3 Connecting lever 4 Female driving means 6 Connecting link 7 Rotating member 20 Fixing means

Claims (1)

(57) [Claims] 1. A first and a second moving knife which reciprocately rotate on a rotary hook base provided below each of two sewing needles to capture and cut a sewing thread between the sewing needle and the rotary hook. A connecting lever that connects the female support bases that rotatably support the first and second moving knives and that can be adjusted to expand and contract according to a change in the position of the rotary hook, and that is connected to a lower shaft of the sewing machine when sewing is completed; And a connecting means for connecting one of the first and second moving scalpels to the scalpel support and the scalpel driving means. In a thread cutting device for a sewing machine, the connecting unit includes: a rotating member provided to be rotatable around a rotating shaft of one of the first and second moving knives; The position of the moving knife provided with the rotating member can be adjusted relative to the support table of the moving knife. A fixing means for a constant, the yarn cutting device twin needle sewing machine to the connecting link to respectively pivotally supported at the other end to said rotating member to said knife drive means at one end, characterized in that it is constituted by.