JPH0133010Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a sewing machine with buttons, and in particular, the present invention takes out a predetermined amount of thread from a thread supply source at the end of button sewing, and calculates the amount of thread required to start the next button sewing operation. This invention relates to a thread take-up device for a sewing machine with a button.

[Prior art]

Conventionally, this type of device was disclosed in U.S. Patent No.
2730980 As shown in the specification and drawings,
A disk is rotatably provided on the upper surface of the sewing machine frame, and a pair of thread guides are provided on this disk with the center axis of rotation sandwiched between them. Some types are equipped with a clamp body that prevents the thread from passing through.When finishing buttoning, the clamp body is first activated to hold the thread, then the disc is rotated to take out a predetermined amount of thread from the thread supply source, and the next There was one that was configured to take out the length of thread necessary to start the button sewing process.

[Problem that the invention attempts to solve]

In general, there are two types of buttons: flat buttons, in which the button is sewn with the button in contact with the work cloth, and flat buttons, in which the button is separated from the work cloth using a spacer and sewn to the work cloth, and then the button is sewn on. It is known that there is a type with a neck-wrapping button in which the thread is wound only around the bundle of threads extending between the work cloths.

When using this neck-wrapped button, when wrapping the thread only around the thread bundle that extends between the button and the workpiece fabric, hold the button vertically with an attachment, etc., and sew with a sewing machine in the same way as with the flat button. but,
At this time, since there is no resistance to the yarn passing by the work cloth, the yarn is pulled toward the supply side and the yarn foot comes off very easily from the binding point of the first stitch.
The amount of thread taken out is required to be much larger than that with flat buttons.

However, since the conventional adjustment of the amount of thread taken out depends only on the amount of rotation of the disc, it is necessary to adjust the amount of thread that can be used for both types of sewing, such as flat button sewing and neck wrapping button sewing, which require extremely different amounts of thread. It was difficult to take it out.

[Purpose of invention]

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a thread take-up device for a button sewing machine that can be used with both flat button sewing machines and neck wrapping button sewing machines.

[Means for solving problems]

In order to achieve the above object, the present invention includes a thread blocker which is disposed closer to the thread supply source than the needle, which enables thread to be supplied when sewing buttons, and which blocks the thread supply when sewing is completed; a rotating disk which is rotatably disposed on the side of the yarn supply source from the yarn blocking device and has a pair of engagement pins sandwiching the rotation center axis, and which changes the yarn path by rotation of the engaging pins;
When the thread path is changed by rotation of the pair of pins, an engaging body is provided that is selectively disposed at a position where the thread can be taken out by engaging the thread, and at a position where the thread is not engaged with the thread. There is.

[Effect]

In the present invention having the above configuration, the thread is taken out by causing the thread blocking device to block the supply of the thread and by rotating the rotary disk to change the thread path. At this time, the amount of yarn taken out when the engaging body is in a position where it can engage with the yarn is much larger than the amount of yarn taken out when the engaging body is in a position where it does not engage with the yarn.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of an embodiment of the present invention will be explained below with reference to the drawings.

In this embodiment, a needle bar 2 is supported at the tip of an arm 1a of a sewing machine frame 1 so as to be movable up and down, and a needle 3 is attached to the lower end of the needle bar 2.
A needle bar holder 4 is attached near the upper end of the needle bar 2.
A balance 5 is protruded from its front part. A looper 6 for single-thread chain stitching is supported within the bed 1b of the sewing machine frame 1 so as to be rotatable around a horizontal axis. As the main shaft 7 provided in the footnote section 1c of the sewing machine frame 1 rotates, the needle 3 is driven up and down via the connecting rod 8, the swing lever 9, etc., and the looper 6 is rotationally driven. A single thread chainstitch is formed by the cooperation of the two.

A feed plate 10 is supported on the upper surface of the bed 1b so as to be movable in the front-back and left-right directions, and a feed plate 11 is attached to the front end of the feed plate 10. Feeding stand 10
A presser arm 12 is rotatably supported at the rear end of the presser arm 12, and the tip of the presser arm 12 is used to clamp the cloth as a workpiece between the feed plate 11 and to attach and detach a button to be sewn onto the cloth. A button holding arm 13 is attached for possible holding. A spring 14 is interposed between the arm 1a of the sewing machine frame 1 and the presser arm 12, and presses and biases the presser arm 12 toward the feed table 10 side. In this embodiment, the feed table 1
0, feed plate 11, presser arm 12, button holding arm 13
A workpiece holder 15 is constituted by the above, and is adapted to be moved across the vertical movement path of the needle 3.

An upright piece 16 is protruded from the upper part of one side of the presser arm 12, and an engagement pin 17 is attached to the upper end of the upright piece 16. A rotary lever 18 is rotatably supported at the lower part of the arm 1a on the right side of the upright piece 16, and the front end of the rotary lever 18 can engage with the engagement pin 17 from below. When the rotating lever 18 is rotated clockwise as shown in FIG. 1, the button holding arm 13 is operated to the button release state via the operating lever 19, and after the button release operation, the button holding arm 13 is operated to the button release state. Rotating lever 18
The front end thereof engages with the engagement pin 17 from below, and the presser arm 12 and button holding arm 13 are raised against the pressing force of the spring 14.

As shown in FIG. 1, a rotary shaft 24 is rotatably supported in the pillar portion 1c of the sewing machine frame 1 near the rear side of the main shaft 7, and is rotated at a reduced speed as the main shaft 7 rotates. The rotation shaft 24 is rotated once for every several rotations of the rotation shaft 24 . An operation control cam 25 is fixed to the outer end of the rotating shaft 24, and an equal radius portion 25a and a pair of recesses 25b separated by a predetermined angular interval (180 degrees) are formed on the outer periphery of the cam 25. In the vicinity of the actuation control cam 25, a driven lever 26 is rotatably supported on the pillar portion 1c via a shaft 27, and the actuation control cam 25 is attached to the upper end of the driven lever 26.
Contactors 26a and 26b, which are comprised of rollers and claws that can be engaged with the outer circumferential surface of the contactors 26a and 26b, are supported.

On the other hand, a tri-arm-shaped rotating member 28 is rotatably supported in the pillar portion 3 above the actuation control cam 25, and one of the arms and the rotating lever 18
A connecting rod 29 is interposed between the two arms, and a driven rod 30 is attached to the other arm. A connecting rod 31 is interposed between the lower end of the driven rod 30 and the driven lever 26, and a pin 32 is inserted at the front end of the connecting rod 31.
It is connected to the driven rod 30 by a pin 33 that fits into the elongated hole 26c at the rear end, and is connected to the driven lever 26 so as to be able to move relative to it by a predetermined amount. A spring 34 is hung between the connecting rod 31 and the sewing machine frame 1, and urges the connecting rod 31 to move rearward, and rotates the driven rod 30 with its upper end as the center of rotation as shown in FIG. It is biased to rotate clockwise.

An eccentric cam 35 is fixed to the main shaft 7 in front of the operation control cam 25. A bifurcated moving body 36 for vertically moving the workpiece holder 15 is rotatably supported by a support shaft 37 in the pillar portion 1c so as to embrace the eccentric cam 35. 35, it is reciprocated between two positions shown by a solid line and a chain line in FIG. A locking piece 36a is bent at the rear end of the movable body 36, and a locking recess 30a is formed at the rear edge of the lower end of the driven rod 30 so as to be able to engage and disengage with the locking piece 36a.

As shown by chain lines in FIG. 1, when the contacts 26a and 26b of the driven lever 26 engage with the equal radius portion 25a of the actuation control cam 25 and the driven rod 30 is disposed at the forward position, is the locking piece 36
a is released from the locking recess 30a, only the movable body 36 is reciprocated as the eccentric cam 35 rotates, and the contacts 26a and 26b of the driven lever 26 are moved back and forth as shown by the solid line in FIG. Operation control cam 2
When engaged with the recess 25b of No. 5, the driven rod 30
is moved rearward by the action of the spring 34. When the moving body 36 is rotated from the solid line position to the chain line position with the rotation of the eccentric cam 35, the locking piece 36a engages with the locking recess 30a, and then the moving body 36 moves from the chain line position to the solid line position. Due to the rotation, the driven rod 30 is moved downward, and the presser arm 12 and button holding arm 13 of the workpiece holder 15 are raised via the rotating member 28, the connecting rod 29, the rotating lever 18, etc. It's becoming like that.

As shown in FIG. 1, a sliding plate 38 is supported on the inner surface of the top of the arm 1a of the sewing machine frame 1 so as to be slidable in the front and back direction by a stepped screw 39, and a pair of convex portions 38a, 38b and a concave portion 38c between both convex portions are formed. A thread take-up lever 40 is rotatably supported by a support shaft 41 inside the arm 1a below the sliding plate 38. A connecting rod 42 is interposed between the thread take-up lever 40 and the remaining arm portion of the rotating member 28, and a projection 42a that engages with the sliding plate 38 is protruded from the upper part of the connecting rod 42. When the rotating member 28 is rotated counterclockwise from the chain line position to the solid line position in FIG. 1 as the driven rod 30 moves downward, the sliding plate 38 slides forward via the connecting rod 42. At the same time, the thread take-up lever 40 is rotated downward to the thread take-up position. The configuration and operation of the rotating member 28 for sliding the sliding plate 38 back and forth, the driven rod 30, the operation control cam 25, etc. are the same as those in Patent Application No. 220843 filed in 1982 by the present applicant. Therefore, further detailed explanation will be omitted.

As shown in FIGS. 1 and 4, the thread blocker 45 includes a cylindrical threaded rod 52 that is fixed through the top of the arm 1a.
, a pair of thread blocking plates 53 fitted onto the threaded rod 52, a spring 54 for applying thread blocking pressure to the thread blocking plates 53, and a threaded rod 52 for adjusting the thread blocking pressure of the spring 54. Adjustment knob 5 screwed into
It consists of 5 and more. An operating pin 56 is fitted into the threaded rod 52 so as to be movable up and down, and its upper end engages with the upper yarn blocking plate 53, and its lower end engages with the protrusions 38a, 3 on the sliding plate 38.
8b and the recess 38c.

Then, during the sewing operation of the sewing machine, the sliding plate 3
8 is moved rearward, this operating pin 56 engages with the front convex portion 38a on the sliding plate 38 and is placed in the upper position, and the upper thread blocking plate 5
3 is lifted from the lower thread blocking plate 53 and the blocking pressure on the thread Y is released, and when the sliding plate 38 is moved forward when the needle 3 is raised on the last needle of one sewing cycle. Just before the needle 3 reaches the top dead center, the operating pin 56 engages with the recess 38c on the sliding plate 38 and is placed in the lower position, and the upper thread blocking plate 53 is in the thread holding position. The actuating pin 56 moves from the rear protrusion 3 on the sliding plate 38 until the needle 3 reaches the top dead center after being lowered and the supply of the thread Y from the thread supply source to the needle 3 side is blocked.
8b and is placed in the upper position so that the upper yarn blocking plate 53 is lifted and the blocking pressure on the yarn Y is released again.

An arm 1 closer to the yarn supply source than the yarn blocking device 45
At the top of a, there is a support shaft 1 with a stepped portion 101 formed thereon.
02 is fixed with a screw, and this stepped portion 10
1 and the upper surface of the top of the arm is an upper rotating plate 10.
3 and a lower rotary disk 104 are rotatably inserted into each other. A long hole 105 extending in the radial direction is formed in the lower rotary disk 104, and the long hole 105 is connected to a through hole installed in the sliding plate 38 and provided at the top of the arm 1a. A protruding pin 38d (not shown) is inserted therein. This pin 38d allows the lower rotary plate 104 to
rotates as the sliding plate 38 moves back and forth.
As shown in FIG.
This upper rotating plate 103
A scale for the amount of yarn to be taken out, which will be described later, is embedded on the top surface. Further, the upper rotating disk 103 is formed with a long hole 107 extending in the circumferential direction, and this upper rotating disk 103 is connected to the screw 10 through the long hole 107.
8 is fixed to the lower rotary plate 104.

A second engagement pin 110 as an engagement body is removably fixed to the stepped portion 101 of the support shaft 102 with a screw 111. When the thread is rotated from the state shown in FIG.

Further, a thread guide 113 and known thread tension devices 43, 44 are fixed to the top of the arm 1a on the side of the thread supply source with respect to the two rotary disks 103, 104, and the thread Y is supplied from a thread supply source (not shown). Thread tension device 44, 43
It is guided to the needle 3 via the thread guide 113, the first engagement pin 106, the second engagement pin 110 and the thread blocker 45.

Further, as shown in FIG. 2, the rear end portion 38e of the sliding plate 38 protrudes outward from the arm 1a, and as the sliding plate 38 moves forward, the thread of the thread tension device 43 It is bent so as to enter between the tension discs 49 and release the thread clamping pressure. The distance between the rear end portion 38e and the recess 38c is determined such that the release of the thread clamping pressure is performed at the same time as the thread blocking pressure of the thread blocking device 45 is applied. At the end of the forward movement of the sliding plate 38, the yarn Y is cut by a cutting device (not shown) in a state in which the operating pin 56 of the yarn blocking device 45 is engaged with the convex portion 38b.

Next, its effect will be explained.

At the start of sewing, the sliding plate 38 is located at the rear, the thread blocking device 45 is in a state where thread can be supplied, the thread tension device 43 is in a state where thread clamping pressure is applied, and the first and second 2 engaging pins 106, 11
0 is separated from the thread Y as shown in FIG. The workpiece holder 15 holds the button and workpiece cloth on the bed surface.

Operation control cam 2 as button attachment work progresses.
5 rotates, and when the final needle 3 rises, the swinging motion of the movable body 36 is transmitted to the rotating member 28, and the sliding plate 38 is moved forward via the connecting rod 42. In conjunction with this back-and-forth movement, the upper rotary disk 103 is rotated counterclockwise in FIG.
The yarn blocking device 45 applies yarn blocking pressure to the yarn Y only while the operating pin 56 is engaged with the recess 38c of the sliding plate 38. This rotation of the upper rotary disk 103 causes the first engagement pin 106 to engage the thread Y and change its path. The second engagement pin 110 moves relative to the first engagement pin 106 so that it engages and bends the thread that is being rerouted. As a result, a predetermined amount of yarn Y is taken out from the yarn supply source.

At the end of the forward movement of the sliding plate 38, the thread blocking device 45 releases the thread blocking pressure again, after which the thread is cut by the cutting device and the button attachment is completed.

At the start of the next button attaching operation, the sliding plate 38 is moved backward in conjunction with the workpiece holder 15 being machined toward the bed surface in order to hold the button and workpiece cloth together. Ru. In conjunction with this backward movement, the upper rotary disk 103 returns from the state shown in FIG. 3 to the state shown in FIG. The amount of thread necessary to complete sewing is secured just before the thread leg comes off from the seam knot point.

Here, the adjustment of the amount of yarn taken out by rotating the upper rotary disk 103 when attaching a flat button will be explained.

With flat buttons, the amount of thread taken out is relatively small, so
The operator can remove the second engagement pin 110 from the stepped portion 111 of the support shaft 102 by loosening the screw 111. Thereafter, loosen the screw 108 and adjust the fixed position of the upper rotary disk 103 relative to the lower rotary disk 104 while referring to the scale, and change the initial position of the first engagement pin 106 to adjust the amount of yarn taken out. do it. At this time, the thread Y is engaged with the first engagement pin 106 as shown by the broken line in FIG. 3, and the relationship between the amount of thread taken out and the scale at this time is shown in FIG. As shown in the graph below.

On the other hand, the adjustment of the amount of thread taken out when performing neck wrapping button attachment will be explained.

Since the neck wrapping button type requires a larger amount of thread to be taken out than the flat button type, the operator must use the second engagement pin 1.
10 may be fixed to the stepped portion 101 of the support shaft 102. After that, as with the above-mentioned flat button attachment, adjust the fixing position of the upper rotary plate 103 by referring to the scale.
The amount of thread to be taken out may be adjusted so that buttoning is completed just before the thread comes out from the seam knot of the first stitch.

Note that the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention, such as rotatably fixing the second engagement pin to the support shaft. It is possible.

[Effect of idea]

Since the present invention is constructed as described above, it has an excellent practical effect in that it can be applied to both the flat button type and the neck-wrapped button type, which have greatly different yarn take-out amounts.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of a button sewing machine embodying the present invention, Fig. 2 is a plan view showing only the main part of the top of the arm of the sewing machine, and Fig. 3 is a thread take-up device of the present invention. FIG. 4 is a partially enlarged sectional view of the yarn blocking device, and FIG. 5 is a graph showing the relationship between the amount of yarn taken up and the scale of the rotary disk. 3 is a needle, 15 is a workpiece holder, 45 is a thread blocker, 103 and 104 are rotating discs, 106 is an engagement pin, and 110 is an engagement body.

Claims (1)

[Claims for Utility Model Registration] A button with a needle 3 that moves up and down, and a workpiece holder 15 that integrally holds the work cloth and the button and moves relative to the vertical movement path of the needle 3. In the sewing machine, a thread blocker 45 is disposed closer to the thread supply source than the needle 3, enables thread to be supplied when sewing a button, and blocks the supply of thread Y when sewing is completed; and a thread stranded in the thread blocker 45. Rotating discs 103 and 104 are rotatably disposed on the supply source side, and are formed with a pair of engagement pins 106 sandwiching a central axis of rotation, and change the yarn route by rotating the engaging pins 106.
When the thread path is changed by the rotation of the pair of engagement pins 106, the pins are selectively disposed at a position where the thread Y can be engaged with and take out the thread, and a position where the thread Y is not involved. and an engaging body 110, which is configured to cause the yarn blocking device 45 to block the yarn supply and rotate the rotary disks 103, 104 to take out the yarn Y from the yarn supply source. Thread take-up device for sewing machines with buttons.