JP2002113277A - Multithread chain stitch sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multithread chain stitch sewing machine that easily removes a thread control cam even if a looper thread is cut and curled and then removes the curled thread while the thread control cam does not interfere with the operation of texture even during sewing. SOLUTION: The multithread chain stitch sewing machine has a bobbin thread delivery device comprising a looper that reciprocates left and right at he lower portion of a throat plate in linking with the rotation of a spindle that is arranged at a sewing machine bed, a thread control cam where the amount of projection from a thread delivery stand changes in linking with the reciprocating movement of the looper, and a passage of reeling thread having a thread hole where the looper string is inserted. The multithread chain stitch sewing machine controls the amount of delivery of the looper string by sliding the looper string on the peripheral surface of the thread control cam. In the sewing machine, the strong control cam is fixed to the end section of a rotary shaft that is arranged next to the spindle, at least one end of a bearing for supporting the rotary shaft forms one portion of an inner wall in the sewing machine bed, and the spindle and the rotary shaft are connected by a timing belt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double chain stitch sewing machine and, more particularly, to rotating a thread control cam between two thread paths arranged on a thread reeling table, and forming a looper on the peripheral surface of the cam. This is used for a double chain stitch sewing machine provided with a lower thread reeling device for controlling the amount of looper thread to be threaded by sliding the thread.

[0002]

2. Description of the Related Art A double chain stitch sewing machine is usually equipped with a
The thread control cam 102 is rotated between the two thread paths 101, 101 disposed above the lower thread 00, and the looper thread LT is slid on the peripheral surface of the cam 102 to control the amount of the looper thread LT fed out. An apparatus 103 is provided. However, in the case of the sewing machine shown in FIG. 5, if the looper thread LT breaks during sewing, the thread end falls between the thread paths 101, 101 and the thread control cam 102, and the shaft of the main shaft S or the thread control cam 102 Part. When such thread wrapping occurs, it has been difficult to remove the thread control cam 102 by shifting the main shaft S having support members such as bearings on both sides. Also, if the thread wound with scissors or a knife is removed without removing the thread control cam 102, the thread control cam 102
Was scratched on the peripheral surface, and the scratches were a factor of increasing the occurrence of thread winding.

As a solution to this problem, Japanese Utility Model Laid-Open No. 57-14
As disclosed in JP-A-7677 and JP-A-9-66183, it has been proposed that a thread control cam is provided outside a sewing machine frame to facilitate its removal. However, in the former proposal, the bearing of the rotary shaft for attaching the thread control cam is also provided on the bracket outside the sewing machine frame, and the bearing cannot receive stable lubrication.
The operating speed of the sewing machine could not be increased, and in the latter proposal, the thread control cam was positioned on the sewing machine arm leg, which was one corner on the sewing machine bed, which hindered the fabric operation during sewing. .

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to remove the thread control cam easily to remove the wound thread even when the looper thread breaks and the thread is wound, and to prevent the thread from being wound during sewing. It is an object of the present invention to provide a double chain stitch sewing machine in which a thread control cam does not hinder fabric operation.

[0005]

According to the present invention, there is provided a looper which reciprocates right and left below a needle plate in accordance with the rotation of a main shaft arranged in a sewing machine bed, and a looper which is interlocked with reciprocation of the looper. A lower thread winding device including a yarn control cam having a variable amount of protrusion and a yarn path arranged on a yarn winding table on both sides of the yarn control cam and having a yarn hole through which a looper yarn is inserted, is provided on a peripheral surface of the yarn control cam. In a double chain stitch sewing machine in which a looper thread is slid in contact to control a looper thread payout amount, a thread control cam is fixed to an end of a rotation shaft arranged side by side with a main shaft, and a bearing for supporting the rotation shaft. At least one end forms a part of an inner wall of the sewing machine bed, and the main shaft and the rotation shaft are connected by a toothed belt.

Further, in the present invention, the thread control cam is arranged in the sewing machine bed, or one end of the thread reeling table is supported so as to be openable and closable up and down along a vertical plane formed in the bed body of the sewing machine bed. desirable.

Further, it is desirable that the inner wall portion of the sewing machine bed in the bearing is horizontally projected, an oil supply hole is provided at an upper side thereof, and an oil drain groove is provided at a bottom side of the bearing along an axis of the rotating shaft.

[0008]

According to the present invention, if the looper thread breaks during sewing and the thread is wrapped around, the thread control cam is removed from the end of the rotary shaft disposed on the sewing machine bed. The bearing that supports the rotating shaft can perform stable lubrication by a known lubrication mechanism. Further, when the lubricating oil is scattered in the sewing machine bed by the driving of the sewing machine, a part of the scattered lubricating oil is supplied to the rotary shaft from the oil supply hole of the bearing through the inner wall of the sewing machine bed. Excess lubricating oil accumulated in the bearing is discharged through a drain groove of the bearing.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a main part of a double chain stitch sewing machine applied to the present invention. Sewing bed M
The cylinder portion A of B projects sideward from the bed body B together with the main shaft S, and the upper surface thereof forms a part of the needle plate 1. Above the needle plate 1, a needle bar 2 to which a needle (not shown) is attached is provided. Below the needle plate 1 is provided a looper 3 which reciprocates left and right in conjunction with the rotation of the main shaft S. The looper 3 is fixed by screws 6 to a looper shaft 5 supported by a bearing 4 of the bed body B. The bearing 4 has a thread path 8 having a thread hole 7 for inserting a looper thread.

A bobbin reeling device 9 is arranged on the bed body B of the sewing machine bed MB. The lower thread reeling device 9 includes a thread control cam 11 attached to an end of a rotating shaft 10 with a screw (not shown), and thread paths 13, 13 arranged on both sides of a groove 12 a of a thread reeling table 12. Become. The rotating shaft 10 is
It is located behind the horizontally extending main shaft S and is arranged side by side with the main shaft S in the sewing machine bed. Also, the bearing 10 of the rotating shaft 10
As shown in FIG. 3, a has an oil supply hole 50 and an oil drain groove 51, at least one end of which protrudes horizontally from the inner wall of the sewing machine bed MB. Oiling hole 50 is used for bearing 10
a is disposed on the upper side of the protrusion, and the oil drain groove 51 is provided on the bearing 10a.
Is located at the bottom. The oil drain groove 51 is formed along the axis of the rotating shaft 10.

On the side of the yarn reeling device 9 of the bearing 10a,
An oil seal 52 is provided, and the bearing 10a
The lubricating oil supplied to is prevented from being scattered. When the lubricating oil is scattered in the sewing machine bed by the driving of the sewing machine, a part of the scattered lubricating oil passes through the inner wall of the sewing machine bed MB and is supplied from the oil supply hole 50 of the bearing 10a to the rotating shaft 10.
Will be supplied. Excess lubricating oil accumulated in the bearing 10a flows down to an oil reservoir (not shown) located below the bed body B through the oil drain groove 51 of the bearing.

The yarn control cams 11 and 11 are composed of two clam-shaped cam plates arranged side by side, and are configured to protrude and retract from the grooves 12 a of the yarn reeling table 12 by the rotation of the rotary shaft 10. The yarn reeling table 12 is supported by the bed body B by a stepped screw 14 so as to be able to rotate (open and close) up and down, and is arranged substantially horizontally. One end of the thread spool 12 is along the vertical plane B1 of the bed body B. In addition, thread reeling table 1
2, a lever-shaped thread guide 15 extending to the upper side of the two clam-type cam plates 11, 11 is fixed by screws 17 via a bracket 16, and the thread reel 12 is connected to a stepped screw 14.
A manual operation lever 18 for rotating around is provided. In the present embodiment, a vertical surface is formed on the inner wall of the bed body. However, the present invention is not limited to this, and a vertical surface may be formed on the outer wall of the bed body.

The yarn paths 13, 13 are formed by grooves 12a of the yarn reeling table 12.
Each is erected in the vicinity, and a thread hole for looper thread insertion is formed in the erected portion. In addition, the thread paths 13, 13
Is fixed on the yarn reeling table 12 by screws 19, 19 so that the position can be adjusted by sliding the yarn paths 13, 13 in the slots 13a, 13a when the screws 19, 19 are relaxed. As shown in FIG. 2, a belt pulley 20 is provided around the rotating shaft 10. This belt pulley 2
Numeral 0 is connected to a belt pulley 21 of a main shaft S by a bed body B by a toothed belt 22, and both belt pulleys 20, 21 have the same number of teeth. In addition, a thread support 23 is installed on the bed body B adjacent to the lower thread reeling device 9. The yarn support 23 is supplied from a yarn supply source to a yarn tensioner group TT (FIG. 4).
(See FIG. 2) to the looper thread reaching the lower thread reeling device 9 with a slight tension.

The operation of the double chain stitch sewing machine described above will be described. When the sewing machine driving motor is operated by depressing a pedal or the like, the main shaft S rotates. When the main shaft S rotates, the looper 3 reciprocates left and right below the needle plate 1, and the rotation shaft 1 rotates via the toothed belt 22.
0 rotates and the clam type cam plate 1 attached to the rotating shaft 10
Numerals 1 and 11 change the amount of protrusion from the yarn reeling table. Due to this change in the amount of protrusion, the looper thread inserted through the thread holes of the thread paths 13, 13 slides on the peripheral surfaces of the clam-type cam plates 11, 11.
The feeding amount of the looper yarn is controlled. In the case where the looper thread breaks during sewing and the thread is wound, if the clam-shaped cam plates 11, 11 are removed from the end of the rotary shaft 10, the wound thread can be easily removed. When the looper 3 reciprocates, the lower thread reeling device 9 is moved to the looper 3.
, The looper yarn reaching the looper 3 is guided through the yarn path 8 attached to the bearing 4.

In this embodiment, the yarn reeling table is arranged substantially horizontally. However, the present invention is not limited to this. For example, as shown in FIG. You may make it incline low. If the looper yarn from the yarn path arranged on the yarn reeling table to the yarn hole of the bearing is slackened, the yarn support 24 is arranged on the cylinder bed as shown in FIG. Thread hole 24
The looper thread may be guided from the thread path to the thread hole of the bearing via a.

[0016]

As described above, according to the present invention, the yarn control cam can be removed from the end of the rotary shaft even if the yarn is wound, and the yarn control cam can be quickly removed without scratching. The operation of removing the yarn wound around the can be performed. Further, since the oil can be stably supplied to the bearing that supports the rotating shaft, the operating speed of the sewing machine can be increased. further,
Since there is no obstacle during sewing, the operation of the fabric can be performed without any intimidation.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a double chain stitch sewing machine applied to the present invention.

FIG. 2 is a schematic side view showing a main part of the sewing machine.

FIG. 3 is a partial cross-sectional view showing a main part of the sewing machine.

FIG. 4 is an external perspective view showing another embodiment of the lower thread reeling device of the sewing machine.

FIG. 5 is an external perspective view illustrating a conventional double chain stitch sewing machine.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 needle plate 3 looper 9 bobbin thread reeling device 10 rotary shaft 10 a bearing 11, 11 clam type cam plate (thread control cam) 12 thread reeling stand 13, 13 thread path 22 toothed belt 50 oil supply hole 51 oil drain groove MB sewing machine bed S spindle

Claims (4)

[Claims] 1. A looper that reciprocates left and right below a needle plate in conjunction with rotation of a main shaft disposed on a sewing machine bed, and a thread control cam that changes an amount of protrusion from a thread reeling table in conjunction with reciprocation of the looper. And a thread path arranged on a thread spool on both sides of the thread control cam, the thread path having a thread hole through which the looper thread is inserted. In a double chain stitch sewing machine that controls a thread feeding amount, a thread control cam is fixed to an end of a rotating shaft arranged in parallel with a main shaft, and at least one end of a bearing that supports the rotating shaft has an inner wall in a sewing machine bed. A double chain stitch sewing machine forming a part, wherein a main shaft and a rotation shaft are connected by a toothed belt. 2. The double chain stitch sewing machine according to claim 1, wherein the thread control cam is disposed in the sewing machine bed. 3. A sewing machine bed comprising a bed body and a cylinder portion protruding laterally from the bed body, and one end of the thread reeler is supported so as to be openable and closable up and down along the vertical plane of the bed body. 3. The double chain stitch sewing machine according to 1 or 2. 4. An inner wall portion of the sewing machine bed in the bearing projects horizontally and has an upper side provided with an oil supply hole,
2. The double chain stitch sewing machine according to claim 1, wherein a bottom side of the bearing is provided with an oil drain groove along an axis of the rotating shaft.