JPH03136691A - Thread feeding device of sewing machine - Google Patents

Abstract

PURPOSE:To draw out both threads in a good condition even though the thread diameters of a needle thread and looper threads are different by dividing the second driving roller into two pieces, holding the needle thread between one side of the divided rollers and the first driving roller, while holding the looper threads between the other side of the divided rollers and the first driving roller. CONSTITUTION:Graspers 11, 12, 13, 19, and 20 consist of a columnar solenoid main bodies 11a to 20a, and disks 11b to 20b fixed to the shaft tips of the solenoids, and when the current is fed, the disks 11b to 20b approach to the solenoid main bodies 11a to 20a, and a needle thread S1 and looper threads S2 and S3 are grasped between both members. The graspers 11 to 13 at the parts closer to the thread feeding source from the first and the second driving rollers 15 and 16 control the thread feeding amount by the first and the second driving rollers 15 and 16, and the graspers 19 and 20 at the close side to a sewing member prevent an excessive drawing out of the needle thread S1 and the looper threads S2 and S3 from the thread feeding source side owing to a tensile force generated at the sewing member side.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thread supply device for simultaneously supplying a plurality of threads applicable to, for example, an overlock sewing machine.

There is a thread supply device for a multi-branch sewing machine that actively unwinds thread and supplies it to a needle and a looper.

The first such device was equipped with a drive roller that was rotationally driven by a motor or the like, and a rotatable driven roller that was biased in a direction that came into contact with the drive roller, and the thread was held between both rollers. The structure was such that the yarn was fed out by the rotational force of the drive roller.

By the way, according to this device, the driven roller does not have a function of actively feeding out the thread, but simply rotates by receiving rotational force from the drive roller via the thread.
A slight braking force is applied to the thread,
The yarn may not be fed smoothly.

To solve this problem, JP-A-1-185287
A device shown in the publication has been proposed. This proposed device is
The driven roller is driven at the same peripheral speed as the drive roller. According to this device, the driven roller no longer acts as a braking force on the thread, making it possible to unwind the thread better. However, on the other hand, when this device is applied to an overlock sewing machine, the following problems occur. There is a problem.

[17] Overlock sewing machines use two types of thread, needle thread and louver thread, so if the above device is applied to an overlock sewing machine, the thread of 24Φ will be transferred between two rollers. In this case, the needle thread and louver thread may have different thread diameters.
The thin diameter yarn is not held well between the two straws, resulting in insufficient payout of the yarn.

Actually FSj k, woolly thread with high elasticity is sometimes used as the louver thread in overlock sewing machines, and in that case, the louver thread becomes very thin compared to the needle thread, and the unwinding of the louver thread may deteriorate. It has been certified.

In order to solve this problem, it may be possible to provide roller pairs of a driving roller and a driven roller separately for the needle thread and the louver thread, but in that case, the number of rollers would increase, resulting in an increase in size and cost. It disappears.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a new thread supply device for a sewing machine that does not cause an increase in size or cost and is capable of feeding out both needle thread and louver thread well even if the diameters of the needle thread and louver thread are different. .

Section MixK Support Maru Mugihikoudan The present invention provides a method for connecting a thread between a first drive roller and a second drive roller that is urged in a direction to contact the roller and is driven at the same circumferential speed as the roller. In the thread supply device of the sewing machine, the second drive roller is divided into two parts, and one divided roller is connected to the first drive port through the first drive port. The needle thread is sandwiched between the rollers, and the louver thread is sandwiched between the other divided roller and the first driving roller.

In the present invention, since the second drive roller is biased in the direction of contacting the first drive roller and is driven at the same circumferential speed as the first drive roller, the thread There is no friction between the roller and the first and second drive rollers.

In addition, since one of the divided second drive rollers holds the needle thread and the other side holds the louver thread, it is possible to stably and simultaneously supply needle thread and louver thread having different diameters.

', JLJJ'LJl! L Fig. 1 is a perspective view showing a thread supply device of a sewing machine according to the present invention, Fig. 2 is an exploded perspective view showing main parts of the present invention, and Fig. 3 is a perspective view showing the assembled state (partially (omitted).

Sl indicates a needle thread, S2 indicates an upper looper thread, and S3 indicates a lower looper thread. Each of the threads Sl, S2, and S3 is led to the thread supply device 10 according to the present invention from a different thread supply source (not shown), and here After each thread h)' is let out by needle 2. It is supplied to the upper louver 3 and the lower louver 4.

The yarn supply device 10 includes three grippers 11 and 12 provided on each yarn along the supply direction of each yarn Sl, S2, and S3.
．． 13, a first yarn path 14 that guides these yarns, a first drive roller 15 and a second drive port to 16 that apply unwinding force to the yarn exiting this yarn path 14, and a connection between these rollers. A second thread path 17 that guides each thread that has come out, a needle thread thread path 18 that guides the needle thread S1 among the threads that have come out of this thread path 17, a needle thread gripper 19, and upper and lower louvers. The yarn amount gripping device 20 is provided.

As shown in FIG. 2, the first driving roller 15 includes a roller main body 15a having a substantially cylindrical shape, and two rollers disposed on both sides.
The roller body 15a is assembled in a state where the roller main body 15a is inserted outside the portion where the protrusions 21a and 22a, which are provided on the gears 21, 22 and have a circular cross section, butt against each other. And a through hole 21b provided in the gear 21.22,
Insert the cylindrical shaft 24 into the shaft 22b.
4, and screw 26 onto the fixing plate 25 attached to the sewing machine frame 1.
DC motor 23 with built-in encoder is stopped
The first drive roller 15 is rotatably supported by being attached to the shaft 23a.

The cylindrical shaft 24 is fixed to the shaft 23a with a screw 21c, and the gears 21 and 22 are fixed to the cylindrical shaft 24 with the screw 21c.
It is stopped at 1c and 22c.

The DC motor 23 to which the cylindrical shaft 24 is attached rotates at a constant speed regardless of the rotational speed of the main shaft of the sewing machine, and this rotation drives the first drive roller 15 to rotate. In addition, Fig. 3 shows the gear 22 and the main body], 5
a is omitted.

On the other hand, the second driving roller 16 is divided into two in the axial direction, and one (left) divided roller 161 has a cylindrical roller main body 161a and a protrusion 30a with a circular cross section to be inserted inside the roller main body 161a. The protrusion 30a is inserted into the inner side of the roller body 161a to be integrated with the roller body 161a, and the two are bonded together. The split roller 161 configured in this manner has one end side of the bottle-shaped shaft 35 inserted into the through hole 30b of the gear 30 fixed to the arm 34 via a screw 36, and is rotatably supported around the shaft 35. . ]r1 The arm 34 is attached via a support rod 33 to a fixture 32 which is screwed to another part of the fixing plate 25 with a screw 31, and is rotatably supported around the support rod 33.

Similarly, the other (right side) divided roller 162 has a cylindrical roller main body 162a and a gear 40 formed with a projection 40a having a circular cross section to be inserted into the roller main body 162a. The roller body 162a is inserted into the roller body 162a and integrated, and the two are bonded together. The divided roller 162 configured in this way has the gear 400 through hole 40b.
One end of a pin-shaped shaft 45 inserted into the arm 44 is fixed to the arm 44 via a screw 46, and is rotatably supported around the shaft 45. The arm 44 that supports the split roller 162 is also attached to the support rod 33. This support rod 33 is attached
It is rotatably supported.

Further, the support rod 33 has a coil spring 37°47,
A ring 38.48 into which a locking rod 39a, 49a is screwed in is inserted to lock one end of the coil spring 37.47, and the other end of the coil spring 37.47 is attached to the arm 34.44.
By locking with the other stopper rods 39b and 49b screwed onto the
It is pressed to the side. This pressing force is applied by once loosening the stop bars 39a, 49a screwed into the ring 38.48, rotating the ring 38.48 in a predetermined direction around the support rod 33, and then loosening the stop bars 39a, 49a. Can be adjusted by tightening.

When in the press biased state, the two gears 21 and 22 of the first drive roller 15 and the two gears 30 and 40 of the second drive roller 16 engage, and the rotation of the DC motor 23 causes the first drive From the two gears 21.22 of the roller 15 example, it is transmitted to the gear 30.40 and the two divided rollers 161,
162 rotates at the same peripheral speed as the first drive roller 15.

11;1 Grip device 11.12, 13.19.20 consists of a cylindrical solenoid body 11a to 20a and a disc itb to 20b attached to the tip of the shaft of the solenoid, and when energized, the disc 11b to 20a 20b is the solenoid body 11a~
20a, the needle thread S1 and the louver thread S2.
The grippers 11 to 13, which are closer to the thread supply source than the first and second drive rollers 15 and 16, control the amount of thread supplied by the first and second drive rollers 15 and 16, and The grippers 19 and 20 located on the side closer to
3 is prevented from being drawn out excessively from the yarn supply source side.

Of the thread holes 14a, 14b, 14c provided in the thread path 14 closer to the thread supply source than the first and second drive rollers 15, 16, the thread hole 14a is connected to one divided roller 161 in the axial direction of the second drive roller 16. The thread holes 14b and 14C are provided at positions corresponding to the other divided roller 162, and the needle thread S1 passed through the thread hole 14a is connected to one of the divided rollers 161 and the first driving roller 15. The louver threads 32, S, which are supplied between the
3 is supplied between the other divided roller 162 and the first driving roller 15.

The roller body 15a of the first drive roller 15 and the two roller bodies 161a and 162a of the second drive roller 16 are made of metal, ceramic, or the like, and have mirror-finished surfaces. This prevents the formation of grooves on the roller surface due to contact with the yarn, and also enables the two divided rollers 161 and 162 to rotate at the same circumferential speed as the first drive roller 15 and to be pinched from both sides as described above. Since the thread is let out in a state where the thread is open, there is no problem even if the rXW force between the thread and the thread becomes small due to the mirror finish, and the thread will not be damaged.

Each yarn Sl, S2. S3 is a state in which the amount of feeding is adjusted by the grippers 11 to 20,
The needle 2. It is supplied to the upper looper 3 and lower looper 4.

When the time has elapsed since the sewing is finished, as shown in FIG. The movable iron core 53a of the solenoid 53 attached to the holder is used to push the second drive roller 16 away from the first drive roller 15, which is in a fixed position, and waits until the next sewing. do.

In the above embodiment, the case where there is one needle thread and two looper threads is explained as an example, but the present invention is not limited to this, and one or more needle threads and one or more looper threads are used. If so, it can be applied in any case.

As detailed above, according to the present invention, the second drive roller is biased in the direction of contacting the first drive roller and is driven at the same circumferential speed as the first drive roller. Therefore, it is possible to prevent the occurrence of friction between the thread and the first and second drive rollers, and the thread can be fed out smoothly. Since the looper threads are held between the needle threads and the needle threads, even if the diameters of the needle thread and the looper thread are different, both threads can be stably supplied at the same time.

In addition, since the first drive roller is shared by both the needle thread and the looper thread, the device can be made more compact and lower in cost.

4,

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a thread supply device of a sewing machine according to the present invention, Fig. 2 is an exploded perspective view showing main parts of the invention, and Fig. 3 is a perspective view showing the assembled state (parts omitted). ). Sl...needle thread, S2. S supply device, 11-13°5...first drive roller, 61.162...dividing opening 40...gear. ■ 3... Looper thread, 10... Thread 19. 20... Grip device, 1 6... Second drive roller, 1 U, 21, 22, 30° Patent a1 Applicant Vegazas Sewing Machine Manufacturing Co., Ltd. Procedures Written amendment (spontaneous) December 15, 1999 2゜3゜1999 Patent Application No. 274724 Name of the invention Relationship with the person who amended the thread supply device of a sewing machine Patent applicant address 5 Sagisu, Fukushima-ku, Osaka City Chome 7-2 Name Pegasus Sewing Machine Manufacturing Co., Ltd. Representative Mima Tendou Voluntary 6 Subject to correction

Claims (1)

[Claims] (1) A thread is sandwiched between a first drive roller and a second drive roller that is urged in the direction of contacting the roller and is driven at the same circumferential speed as the roller to form the first stitch. In a thread supply device of a sewing machine that supplies the necessary amount of thread for the purpose of 1. A thread supply device for a sewing machine, characterized in that the looper thread is held between a split roller and a first drive roller.