CN1441106A

CN1441106A - Double thread seam locking sewing machine

Info

Publication number: CN1441106A
Application number: CN03106422A
Authority: CN
Inventors: 西川雅彦; 井内裕之; 饭田直正
Original assignee: Pegasus Sewing Machine Manufacturing Co Ltd
Current assignee: Pegasus Co Ltd
Priority date: 2002-02-26
Filing date: 2003-02-25
Publication date: 2003-09-10
Anticipated expiration: 2023-02-25
Also published as: TW595621U; CN100507126C; JP2003245486A

Abstract

The invention provides a double chain stitching sewing machine by which productivity is improved by preventing skipping of stitch occurring when following cloth is sewed. The double chain stitching sewing machine is provided with: a vertically moving needle; a needle plate arranged on a sewing machine bed and allowing the needle to pass through; a looper which moves elliptically to the right and left between the forwarding position and the backward position of the needle plate; and a hook which is to be engaged with a looper thread connected with cloth from the looper by moving forward and backward from the side of the backward position of the looper when sewing is finished. A blowing pipe is arranged behind the looper to position the looper thread reaching the hook from the looper on this side compared with the needle passing-through point of the needle plate by air from the blowing pipe when the looper is moved back when sewing is started.

Description

Double-thread overlock sewing machine

Technical field

The present invention relates to when sewing finishing, the free end of the looper thread that remains in the sewing pusher side be remained on the going-back position side of looper, be the ready double-thread overlock sewing machine of making of follow-up cloth.

Background technology

As original double-thread overlock sewing machine, as shown in Figure 5, when sewing finishing, link looper thread 14 on the cloth W from looper 3 with hook 16 traction, this has been well-known.This hook 16 is advanced and retreat from the going-back position side of looper 3, and thus, looper thread 14 and

needle thread loop

6L, 7L are drawn on the fixed cutting tool 17 on the going-back position side that is configured in looper 3.Be fixed cutting knife 17 of this trailed each

line

6L, 7L, 14 cuts off, and is intactly kept by hook 16 and line maintenance spring 22 because this cut-out remains in the free end of the looper thread 14a of sewing pusher side.The looper thread 14a that remains in the sewing pusher side is linked on the line supply source (figure does not show) through the aperture 3a of looper 3 by hook 16.The action of hook 16 is generally carried out when looper 3 is in progressive position, and at this moment, the top of

6,7 is positioned at the top of needle plate 5.

When beginning the making of follow-up cloth, shown in Fig. 6 (a),

6,7 holds with both hands with both hands and gets from looper 3 to hook 16 looper thread 14aa.That is, the

6,7 that descends when looper 3 retreats connects needle plates 5, holds with both hands with both hands to get from looper 3 to hook 16 looper thread 14aa.When continuing to make same as before, use the rear portion of the pin that rises again through bottom dead centre to form

needle thread loop

6L, 7L, while advancing to hold with both hands with both hands, looper 3 gets needle thread loop 6L, 7L.Thus, entered by looper 3 to the looper thread 14aa of hook 16 by looper 3 and to hold with both hands with both hands among needle thread loop 6L, the 7L that gets, its part becomes round shown in Fig. 6 (b).

; in by the double-thread overlock sewing machine that constitutes like this; the part of 16 looper thread 14aa becomes round from looper 3 to hook on 1 stitch of beginning because making; so remain in as shown in Figure 7, the looper thread 14a of sewing pusher side and be out of shape by hold with both hands with both hands the triangle of the line that the needle thread loop 6L, the 7L that get form of looper 3.Its result, the pin 6 that descends when looper 3 retreats does not enter in the above-mentioned thread triangle, has produced wire jumper.In addition, this wire jumper not only has when the sewing beginning, also takes place when continuing sewing, so can not form linear slit on cloth, exists the problem that can not boost productivity.

Thereby problem of the present invention, its purpose are to provide a kind of double-thread overlock sewing machine that wire jumper can be boosted productivity again that can prevent to produce when the making of follow-up cloth.

Summary of the invention

In order to achieve the above object, double-thread overlock sewing machine of the present invention, have: the pin that moves up and down, the needle plate that is configured on the sewing machine head and is connected by this pin, at the looper that carries out elliptic motion about between progressive position and the going-back position below the needle plate, when sewing finishes from the going-back position advance and retreat of looper and be fastened on from looper and link hook on the looper thread on the cloth, it is characterized in that, at the rear of looper configuration ajutage, the looper thread from looper to hook when the looper that Sewing machines is begun by the air of being sent here by this ajutage retreats is positioned at the front of the pin breakthrough point of needle plate.

Have again, preferably ajutage is configured in the sewing machine head, in addition, can substitute the movable cutting knife of making cutter mechanism to hook, when hook retreats, cut off from looper and link looper thread on the cloth.

According to the present invention, after hook retreats, blow by the ajutage that is configured in the looper rear.Thereby make looper thread from looper to hook be positioned at the front of pin breakthrough point, the pin that the looper of sewing beginning descends when retreating does not hold with both hands with both hands and gets looper thread from looper to hook.And when looper arrived progressive position once more, the looper thread from looper to hook did not twine mutually with needle thread loop etc.That is, after 2 stitch, the triangle of line is suitably formed, and the pin that descends when looper retreats enters in the thread triangle reliably.

Have again,, when carrying cloth, do not hindered because ajutage is configured in the sewing machine head.In addition, because hook is substituted the movable cutting knife of making cutter mechanism, so can make all compacter of device, have again, link looper thread on the cloth if cut off from looper when hook retreats, the operator just can be without the scissors trimming.

Description of drawings

Fig. 1 is the major part stereogram that is applicable to double-thread overlock sewing machine of the present invention.

Fig. 2 is the key diagram of the summary shape of expression needle plate of above-mentioned Sewing machines and work feed tooth.

Fig. 3 is the approximate vertical view of the process that begins with above-mentioned stitching sewing machine of expression.

Fig. 4 is the key diagram of the process that begins with above-mentioned stitching sewing machine of expression.

Fig. 5 is that expression is made the key diagram of the tangent line process of end of a period with double-thread overlock sewing machine.

Fig. 6 is the approximate vertical view of the process that begins with original double-thread overlock sewing machine of expression.

Fig. 7 is that expression is made the key diagram of the process of beginning with original double-thread overlock sewing machine.

The specific embodiment

Use the description of drawings embodiments of the invention below.Fig. 1 is to use the stereogram of the major part of double-thread overlock sewing machine of the present invention.On the cylinder head (sewing machine head) 1 of this Sewing machines, have: up and down four direction motion and make work feed tooth 2 that cloth W sends to arrow F direction, the looper 3 that shakes to the direction of intersecting with cloth feeding direction F and the needle plate of fixing by screw hole 45 (with reference to Fig. 2).Above cylinder head 1, the needle bar 9 that left pin 6 and right pin 7 are installed by pin folder 8 is set.Each

6,7 extends downwards, and its top ends is owing to moving up and down of needle bar 9 connects needle plate 5.Pin breakthrough point 5a, the 5a of needle plate 5 become the base end side of the needle board claw 5c that extends to cloth feeding direction F as shown in Figure 2.

Work feed tooth 2 is made of main work feed tooth 2a and differential cloth-feeding tooth 2b as shown in Figure 2.The top one-tenth of each

work feed tooth

2a, 2b is concavo-convex, and the work feed teeth groove 5b place at needle plate 5 when driving with Sewing machines passes in and out.The upright 2aa of portion that establishes of each

work feed tooth

2a, 2b, 2bb attenuates.Looper 3 is installed on the curved needle shaft 11 by looper platform 10, with the rotation interlock of machine spindle and carry out elliptic motion.By this elliptic motion, below needle plate 5, looper 3 rocks from side to side between progressive position and going-back position.On the top ends of each

6,7, be provided for inserting line hole 6a, the 7a of

cleansing pin line

12,13, on the top ends of looper 3, be provided for inserting the aperture 3a of logical looper thread 14.

In addition, the right side of the work feed tooth 2 in Fig. 1, promptly the base end side at sewing machine head 1 disposes cutter mechanism 15.Cutter mechanism 15 has: become the hook 16 of movable cutting knife, the fixed cutting tool 17 of going-back position side that is configured in looper 3 and the line that is attached on the fixed cutting tool 17 and keep spring 22.Hook 16 makes it advance and retreat on looper 3 by having omitted illustrated drive unit, makes it to be fastened on from looper 3 and links on the looper thread 14 of cloth W.The looper thread portion that is stuck is cut off after being drawn on the fixed cutting tool 17 by hook 16, be divided into the looper thread (not shown) that remains on the cloth W and remain in the sewing pusher side looper thread 14a.The free end that remains in the looper thread 14a of sewing pusher side is kept spring 22 clampings by hook 16 and line.Hook 16 in advance and retreat on the looper 3 also is fastened on needle thread loop 6L, the 7L, and be fixed cutting knife 17 of this

needle thread loop

6L, 7L cuts off.

At the rear of looper 3 configuration ajutage 18.It is fixing that ajutage 18 is sewed the clamping plate 19 of head 1, and the cardinal extremity of ajutage 18 is connected with source of the gas (scheming not show) through managing 21.In addition, ajutage 18 is configured to surround the upright form of establishing the 2aa of portion of main work feed tooth 2a, and its top ends has air outlet 18a.The air outlet 18a of ajutage 18 only carries out official hour towards the opposite direction of cloth feeding direction F from the air-supply of source of the gas when sewing begins.

The following describes the effect of above-mentioned formation.End and looper 3 when arriving progressive positions making, by the start drive unit, hook 16 from the going-back position side advance and retreat of looper 3 and be fastened on link looper thread 14 on the cloth W from looper 3 on.This looper thread 14 is by hook 16 tractions, and the cutting knife 17 that is fixed cuts off.At this moment, also drawn by hook 16 with looper thread 14 respectively by looper 3 needle thread loop 6L, the 7L that gets that hold with both hands with both hands, the cutting knife 17 that is fixed cuts off.Remain in the free end of the looper thread 14a of sewing pusher side by cut-out, shown in Fig. 3 (a), be maintained at hook 16 sides.Then follow-up cloth is configured on the sewing machine head 1.And after the driving of beginning Sewing machines, source of the gas (figure a does not show) start stipulated time is by the air outlet 18a air-supply of ajutage 18.At this moment shown in Fig. 3 (b), 16 looper thread 14aa is bent and is positioned at the front of the pin breakthrough point 5a of needle plate from looper 3 to hook.

Each

6,7 that descends when looper 3 retreats connects needle plates 5, but shown in Fig. 3 (c), does not hold with both hands with both hands to get from looper 3 to hook 16 looper thread 14aa.Then, needle thread loop 6L, the 7L of the pin that bottom dead centre rises of learning from else's experience that hold with both hands with both hands while looper 3 advances.Thus, 16 the looper thread 14aa from looper 3 to hook holds with both hands with both hands among needle thread loop 6L, the 7L that gets though enter by looper 3, does not become the state of circumvolution on needle thread loop 6L, 7L.That is, when looper 3 arrived progressive position once more, 16 looper thread 14aa was not entangled on needle thread loop 6L, the 7L from looper 3 to hook.Its result, after 2 stitch, indeformable by the triangle of looper thread 14a that remains in the sewing pusher side and the line that

needle thread loop

6L, 7L form, the

6,7 that descends when looper 3 retreats enters in the thread triangle as shown in Figure 4 reliably.

When proceeding the driving of Sewing machines like this, the free end of looper thread is sent with cloth, and the line hold mode that keeps spring 22 to keep by hook 16 and line is disengaged.In the present embodiment, begin again to carry out the air-supply of ajutage immediately after Sewing machines drives, but also be not limited to this, blow in the time of also can or placing follow-up cloth after the advance and retreat hook.Mainly be, as long as it is just passable to make looper thread from looper to hook be positioned at the front of pin breakthrough point of needle plate when the looper of sewing beginning retreats.In addition, at this time, hold, so when weakening the tension force of the looper thread that remains in the sewing pusher side in advance, crooked looper thread from looper to hook becomes easy owing to removed wire clamp with tension disk etc.Have again, in the present embodiment, when from the air-supply of the air outlet of ajutage, best driven at low speed Sewing machines.

As mentioned above, according to the present invention, because the not circumvolution of looper thread from hook to looper is on needle thread loop, so can suitably form the later thread triangle of 2 stitch.Its result, the pin that descends when looper retreats enters in the thread triangle reliably, does not produce wire jumper, thereby can boost productivity.

Claims

1. double-thread overlock sewing machine, have: the pin that moves up and down, the needle plate that is configured on the sewing machine head and is connected by above-mentioned pin, carry out the looper of elliptic motion about between progressive position and going-back position below the needle plate, when sewing finishes from the going-back position advance and retreat of looper and be fastened on hook on the looper thread of linking from looper on the cloth, it is characterized in that, at the rear of looper configuration ajutage, the looper thread from looper to hook when the looper that Sewing machines is begun by the air of being sent here by this ajutage retreats is positioned at the front of the pin breakthrough point of needle plate.

2. double-thread overlock sewing machine as claimed in claim 1 is characterized in that ajutage is configured in the sewing machine head.

3. double-thread overlock sewing machine as claimed in claim 1 or 2 is characterized in that, the double movable cutting knife of doing cutter mechanism of hook, and the looper thread of linking on the cloth from looper is cut off when hook retreats.