JPH09767A - Sewing machine - Google Patents

Abstract

PURPOSE: To easily set thread to a tension imparting device and a needle thread take-up device and to shorten the time required for the operation. CONSTITUTION: The tension imparting device 40 is provided with at least a pair of fixed thread guides 50 arranged with a prescribed interval in a vertical direction and a movable thread guide 60 disposed in a part separated from the fixed thread guides 50 for a prescribed distance to a rear part capable of being passed between the fixed thread guides 50 and moved and operated to the front. Also, the needle thread take-up device 80 is provided with at least a pair of thread guides 86 arranged with the prescribed interval in the vertical direction, a needle thread take-up body 88 for repeating reciprocating operations in back and forth directions synchronized with the vertical driving of a sewing needle 14 and a thread guard part to be repeatedly passed between the thread guides 86 by the reciprocating operation of the needle thread take-up body 88.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine equipped with a tension applying device for applying tension to a yarn and a balance device for delivering the yarn.

[0002]

2. Description of the Related Art While a sewing machine is in operation, a tension is applied to a thread supplied to a sewing needle by a tension applying device, and the thread operates in synchronization with the vertical movement of the sewing needle. The required amount of yarn is delivered by the balance device.

A conventional tension applying device is composed of a first tension applying device and a second tension applying device. The first tension applying device has a structure in which two tone plates are supported by one mandrel in a state of being pressed against each other by a spring force, and the mandrel is provided with a yarn path having upper and lower two threading holes. Has become. Further, in the second tension applying device, a rotary tone plate, in which two plates are integrally joined to one mandrel, is supported in a state of receiving rotational resistance due to a spring force, and a tension spring is attached to the mandrel. The structure is provided. On the other hand, the conventional balance device is equipped with a balance that reciprocates in synchronization with the vertical movement of the sewing needle (needle bar). A threading hole is formed at the free end of this balance, and the balance is positioned below the balance. Is provided with a plate-shaped yarn path having a threading hole.

In order to set the thread, the thread is first passed through the thread passing hole above the thread path in the first tension applying device, between the two tension trays, and the thread passing hole below the thread path. .
Next, this thread is wound once around the rotary tension disc of the second tension applying device, is hooked on the tension spring, and is then guided to the balance device. In this balance device, a thread is passed through a threading hole of the thread path located below the threaded thread and a threading hole of the threaded thread in this order, and then the thread is guided to a sewing needle.

[0005]

It is a very complicated work to set the thread on the conventional tension applying device and the balance in this way, and in particular, the sewing machine has a plurality of sewing heads, and each sewing head In the case of a multi-head multi-needle type having a plurality of sewing needles, it takes a lot of time to set the thread.

An object of the present invention is to simplify thread setting on the tension applying device and the balance device, and to reduce the time required for thread setting even in a multi-head multi-needle type sewing machine.

[0007]

According to a first aspect of the present invention, in a sewing machine, a tension applying device has at least a pair of fixed thread guides arranged vertically with a predetermined interval, and a predetermined backward direction from these fixed thread guides. And a movable thread guide which is provided at a position separated by a distance and which is movable between the fixed thread guides and can move to the front thereof. A thread guide, a balance body that repeats reciprocating movements in the front-rear direction in synchronization with vertical movement of a sewing needle, and a thread hooking section that repeatedly passes between thread guides by the reciprocating movement of the balance body. And In setting the yarn, in the tension applying device, the movable yarn guide is moved in front of the fixed yarn guide, so that the yarn is passed straight between the fixed yarn guide and the movable yarn guide. After that, by returning the movable yarn guide to the rear of the fixed yarn guide, the yarn is passed in a bent state with respect to the fixed yarn guide and the movable yarn guide, and tension is applied. Further, in the balance device, if a thread is added to the pair of thread guides, the thread is fed out in synchronization with the up-and-down drive of the sewing needle by the movement of the thread hooking portion accompanying the reciprocating motion of the thread balance body.

A second invention is the sewing machine of the first invention, wherein the sewing machine is a multi-needle type having a plurality of sewing needles.
Moreover, at least the tension applying devices are provided in correspondence with the number of sewing needles. A third invention is characterized in that, in the sewing machine of the second invention, a single balance device is provided, and a sewing needle and a tension applying device selected for sewing are made to correspond to the balance device. Therefore, a single balance body can handle multiple sewing needles,
The structure of the sewing machine is simplified.

[0009]

Next, embodiments of the present invention will be described. The following embodiments apply the present invention to a sewing machine having a multi-needle type sewing head. Embodiment 1 FIG. 1 is a sectional view showing a side surface of a sewing machine head, and FIG. 2 is a front view of the sewing machine head. As shown in these drawings, the needle bar case 10 has sewing needles 1 at the lower ends thereof.
A plurality of (six) needle bars 12 including four are provided. The needle bar case 10 can be slide-controlled with respect to the sewing machine arm 100 in the width direction of the sewing machine head (the left-right direction in FIG. 2), and any one of the needle bars 12 is selected by this slide control. This selected needle bar 12
Is driven by the rotation of the sewing machine main shaft 101.
And, it is driven up and down through a driving mechanism which is interlocked therewith.

A balance case 82 of the balance device 80 is fixed to the upper surface of the needle bar case 10. Moreover, the balance case 8
A bracket 22 is fixed to the upper surface of 2, and a support substrate 24 is fixed to the front surface of the bracket 22. As many tensioning devices 40 as the needle bars 12 are attached to the support substrate 24. A rail portion 26 is formed on the upper front surface of the support substrate 24, and the same number of thread guide tensions 30 as the needle bars 12 are provided therein. Note that yarn paths 18 and 20 are fixed to the front surface of the needle bar case 10 at two locations, namely, an upper and lower intermediate portion and a lower portion thereof, and these yarn paths 18 and 20 are cut into a substantially V shape. The same number of thread guiding portions as the needle bars 12 are formed.

First, the tension applying device 40 will be described. 3 is a side view showing one tension applying device 40, FIG. 4 is a front view of the tension applying device 40, and FIG. 5 is an exploded perspective view of the tension applying device 40. As is apparent from these drawings, the tension applying device 40 includes a housing 42 in which a fixed base 42A and a cover plate 42B are coupled to each other with a spacer 44 interposed therebetween. The housings 42 of the tension applying devices 40 adjacent to each other have the spacer 4 between them.
5 are connected with each other.

The fixed base 42A and the cover plate 4
2B and housing 42 of each tension applying device 40
Are coupled by penetrating two upper and lower coupling bolts 48 over each tension applying device 40 and tightening.
Two mounting brackets 46 are fixed to the housings 42 of the tension applying devices 40 located on both the left and right sides by the above-mentioned both coupling bolts 48. The housings 42 of the yarn tension applying devices 40 are collectively attached to the support substrate 24 by the mounting brackets 46.
Fixed to.

The housing 4 is attached to the fixed base 42A.
Five fixed thread guides 50 are fixed in the vertical direction at a predetermined distance on the front surface side in the inside of 2. The tip ends of these fixed thread guides 50 are respectively inserted into the holes 51 formed in the cover plate 42B. Similarly, on the fixed base 42A, two pins 52 whose end faces are inclined are fixed in the lower portion on the front surface side in the housing 42 in the vertical direction at a predetermined interval. The inclined end surfaces of these pins 52 have holes 53 formed in the cover plate 42B.
Will enter each.

The fixed base 42A has a housing 4
A movable base 56 is provided on the inner side of 2. That is, the fixed base 42A has a guide hole 54 long in the front-rear direction.
Is formed, and the bent portion 59 formed on the movable base 56 is inserted therein. This allows the movable base 56 to move in the front-rear direction along the guide hole 54. Further, the movable base 56 is provided with guide portions 57 on the upper and lower sides thereof, and the tip portions thereof are two grooves 61 formed in the cover plate 42B and long in the front-rear direction.
Respectively engaged with. This stabilizes the posture when moving the movable base 56 in the front-rear direction.

Four movable yarn guides 60 are fixed to the movable base 56 at predetermined intervals in the vertical direction. The tip of each movable thread guide 60 has a cover plate 42.
It engages with the groove 61 of B and another two grooves 62 formed in parallel with these. Each movable thread guide 60
Are arranged at intervals so as to be located between the fixed thread guides 50 in the vertical direction (see FIGS. 3 and 4), and the grooves 61 and 62 are covered with the cover plate 42B as shown in FIG. The front side of each is open. Therefore, when the movable base 56 is at the retracted position in FIG. 3, the movable yarn guides 60 are located at a certain distance rearward from the fixed yarn guides 50. However, as shown in FIG. By moving forward, the movable yarn guides 60 pass between the fixed yarn guides 50 and are positioned in front of these fixed yarn guides 50.

FIG. 6 is a plan view of the tension applying device 40. As is clear from this drawing, the fixed base 42A
Is provided with a support piece 64 projecting outward at the front end of the guide hole 54. A rod 66 having a screw on the outer periphery is supported on the support piece 64 so as to be movable back and forth. At the front end of this rod 66, the knob 6
7 is fixed, and the rear end portion of the rod 66 has a nut 5 fixed to the bent portion 59 of the movable base 56.
It is screwed in 8. On the axis of the rod 66, the spring 6 is provided between the support piece 64 and the bent portion 59.
8 are provided. Due to the urging force of the spring 68, the rod 66 is in a position where the end surface of the large diameter portion 66a is received by the support piece 64 as shown in FIG. 6, and the movable base 56 is retracted to the position shown in FIG. 3, for example. There is.

As shown in FIGS. 3 to 6, a stepped bolt 72 is fixed to the cover plate 42B by a nut 74, and the tension spring 7 is provided on the shaft of the stepped bolt 72.
0 is attached. The fixed base 42A is formed with a hole 76 for avoiding interference with the head of the stepped bolt 72. Further, each of the fixed base 42A and the cover plate 42B has a semi-arcuate curved portion between the pins 52 having the inclined end faces, and a fingertip can be inserted between the pins 52. .

FIG. 8 is an enlarged perspective view showing some of the yarn path tensions 30. As is clear from this drawing, the thread tension 30 has a structure in which a holding plate 34 is supported by a core rod 32 fixed to the rail portion 26 of the support substrate 24, and a knob 36 is screwed into the core rod 32. Has become. A spring 38 is provided between the holding plate 34 and the knob 36 to press the holding plate 34 against the front surface of the rail portion 26. This pressing force can be adjusted by the screwing amount of the knob 36 with respect to the core rod 32. It should be noted that the presser plate 34 has a total of 4 in the vertical and horizontal directions.
Individual guide pieces 35 are formed.

Next, the balance device 80 will be described. FIG. 9 is an enlarged plan view showing the balance device 80 partially in section, and FIG. 10 is a perspective view showing a part of the balance device 80. As is clear from these drawings, the balance case 82 is formed with as many balance storage portions 83 as the needle bars 12. The bottom surface and the front surface of each balance storage portion 83 are open, and the upper surface of the opening portion 84 on the front surface side is also open. Three thread guides 86 are fixed to each of the balance accommodating portions 83 in the respective opening portions 84 in the vertical direction at predetermined intervals. Further, two guide grooves 85 are formed on both side surfaces of each balance accommodating portion 83 so as to pass between the yarn guides 86 in the front-rear direction (see FIGS. 1 and 10).

In each of the above-mentioned balance accommodating portions 83, as shown in FIGS. 1 and 10, two upper and lower balance bodies 88 fixed to each other via a spacer 92 are accommodated. Both side edges of these balance bodies 88 are engaged with the guide grooves 85, respectively, and the balance bodies 88 are movable only along the guide grooves 85 in the front-rear direction. A thread wiping portion 90 and a thread hooking portion 91 are formed at the tip of each balance body 88, and a rubber plate magnet 93 is provided on the rear end surface of the spacer 92 as shown in FIGS. 1 and 9. Is fixed.
The magnet 93 can be attracted to a magnetic plate fixed to the rear side surface of the balance storage portion 83. An engaging portion 94 is provided on the lower surface of the rear end of the lower balance body 88.

When the sewing machine main shaft 101 shown in FIG. 1 rotates, a drive lever 104 supported by a shaft 105 on the sewing machine arm 100 is interlocked with the rotation of a balance drive cam 103 fixed on the shaft of the sewing machine main shaft 101. The shaft 105
It is designed to reciprocate about the axis of. An interlocking lever 96 is rotatably connected to the tip end of the drive lever 104, and a convex portion engageable with the engaging part 94 of the balance body 88 is attached to the tip end of the interlocking lever 96. 97
Are formed. Further, the interlocking lever 96 is biased by a torsion spring 98 provided at a connecting portion with the drive lever 104 in a direction to engage the convex portion 97 with the engaging portion 94 of the balance body 88.

As described above, one needle bar 12 is selected by the slide control of the needle bar case 10, and at the same time, the balance body 88 accommodated in the balance accommodating section 83 corresponding to the selected needle bar 12 is formed. The convex portion 97 of the interlocking lever 96 engages with the engaging portion 94 of. This selected balance body 88 repeats the reciprocating operation in the front-rear direction by the drive lever 104 and the interlocking lever 96 reciprocating between the solid line position and the imaginary line position of FIG. 1 by the rotation of the sewing machine main shaft 101. . When the balance 88 moves forward as shown by the phantom line in FIG. 9, the thread wiping portion 90 and the thread hooking portion 91 pass between the thread guides 86 and are located in the opening 84. In the portion 84, the thread wiping portion 90 and the thread hooking portion 91 are released from the guide groove 85 on one side (left side in FIG. 9).

A solenoid 110 is arranged above the interlocking lever 96 so as to face downward.
0 is a support base 1 for the upper surface of the sewing machine arm 100.
It is fixed through 11. A roller retainer 113 that rotatably supports a roller 112 is fixed to the plunger of the solenoid 110. This solenoid 110
Is operated to lower the roller 112, the interlocking lever 96 is pushed down against the biasing force of the torsion spring 98 as shown in FIG. This allows the interlocking lever 96
The engagement between the convex portion 97 and the engaging portion 94 of the balance body 88 is released.

Therefore, when the needle bar 12 is selected, the solenoid 110 is operated to release the engagement between the convex portion 97 of the interlocking lever 96 and the engaging portion 94 of the balance body 88 as shown in FIG. The slide control of the needle bar case 10 is performed with. At this time, the interlocking lever 96 is kept in the depressed position, and the drive lever 104 is rotated by the rotation of the sewing machine main shaft 101.
By the reciprocating rotation of, the reciprocating operation is performed between the solid line position and the virtual line position in FIG. In this state, the balance body 88 does not operate even if the sewing machine main shaft 101 is rotated, and the multi-head sewing machine performs a clutch function of the balance drive mechanism when stopping an arbitrary sewing machine head. Each balance body 88 when the needle bar 12 is selected, or the balance body 88 that has not been selected after the selection is selected, is attracted by the magnetic plate of each balance storage portion 83 and the magnet 93, and the solid line in FIG. Held in position.

Now, the yarn Y is unwound from a thread spool provided in a thread stand (not shown), and as shown in FIGS. 1 and 2, the yarn path tension 30, the thread tension applying device 40, the thread balance device 80, the yarn paths 18, 20. Is passed through in this order and is guided to the sewing needle 14 of the needle bar 12. The yarn Y is set on the yarn path tension 30 by sliding the yarn Y from the side of the holding plate 34 shown in FIG. 8 between the holding plate 34 and the rail portion 26 of the support substrate 24. The spring 38 is attached to the thread Y.
An appropriate tension is applied by sandwiching between the presser tray 34 and the rail portion 26 by means of which the yarn Y is surely brought into contact with the fixed yarn guide 50 and the movable yarn guide 60 of the next yarn tension applying device 40. be able to. The yarn Y set in the yarn path tension 30 is the same as the pressing plate 3
The pressing plate 34 and the rail portion 26 are connected by the respective guide pieces 35 of 4 above.
It is held so that it does not come off from between.

To set the yarn Y on the yarn tension applying device 40, the knob 67 of the rod 66 is pulled forward to advance the movable base 56 from the position shown in FIG. 3 to the position shown in FIG. By the forward movement of the movable base 56, the movable yarn guides 60 are moved to the fixed yarn guides 50.
It is located in front of these fixed thread guides 50 through the space. Then, the yarn Y is moved between the fixed yarn guide 50 and the movable yarn guide 60 and moved from the right side to the left side in FIG.
Pass it straight between 0 and 60. After this, the movable base 5
When 6 is returned to the position shown in FIG. 3 by the force of the spring 68, the yarn Y is hooked on each fixed yarn guide 50 and each movable yarn guide 60 and is in a bent state.

Then, the above-mentioned both pins 52 whose end faces are inclined
By pushing the yarn Y into the inside of the housing 42 along the inclined end surface of the, the yarn Y is passed through the rear side of the pins 52. Here, a fingertip is inserted between the pins 52, the yarn Y is pinched, and the yarn Y is hooked on the tension spring 70 as shown in FIG. As a result, a predetermined tension is applied to the yarn Y. When adjusting the tension according to the sewing pattern and the type of thread Y, the rod 66 is rotated around the axis by the knob 67, and the movable base 56 is moved in the front-rear direction. By this, the distance between the fixed yarn guides 50 and the movable yarn guides 60 is adjusted, and the yarn guides 50,
The contact area of the yarn Y with respect to 60 changes, and as a result, the mutual contact resistance increases or decreases, and the tension with respect to the yarn Y is adjusted. The function of the tension spring 70 is to detect thread breakage. For example, if the tension of the thread Y does not act on the tension spring 70 due to thread breakage, the elasticity of the tension spring 70 causes the tension spring 70 to remain in contact with the upper pin 52. By utilizing this state, the power supply circuit of the yarn breakage detector is turned on.

To set the yarn Y on the balance device 80, the yarn Y sent downward from the tension applying device 40 is guided along each yarn guide 86 of the balance accommodating section 83.
The thread guides 18 and 20 are guided by the V-shaped thread guide portions and guided to the sewing needle 14. By threading the thread Y guided to the sewing needle 14 onto a thread holding member (not shown) and stretching it, the thread Y
Is surely attached to each thread guide 86.

When the sewing machine main shaft 101 is rotated,
The balance body 88 housed in the balance storage portion 83 corresponding to the needle bar 12 selected by the slide control of the needle bar case 10 reciprocates between the solid line position and the virtual line position in FIG. Then, the thread wiping portion 90 and the thread hooking portion 91 of the balance body 88 are released from the guide groove 85 on one side in the opening portion 83 of the balance storing portion 83, so that the balance body 88 first moves from the solid line position to the imaginary line position. When the yarn Y moves, the yarn Y
In the interval between 6, the yarn is wiped by the yarn wiping unit 90 and guided into the yarn hooking unit 91. Then, as the balance body 88 returns from the imaginary line position to the solid line position, the yarn Y is drawn behind the yarn guide 86 as shown in FIG. 1 or 10, whereby the yarn Y is removed from the yarn spool of the thread stand tray. Be paid out.

Embodiment 2 FIGS. 12 to 15 show an embodiment of a sewing machine in which a single balance device 120 is used for many needle bars 12. FIG. 12 is a sectional view showing a side surface of the sewing machine head of the second embodiment, and FIG. 13 is a front view of the sewing machine head. As is apparent from these drawings, the same number (six) slits 122 as the needle bars 12 are formed in the front surface of the needle bar case 10 in a predetermined range in the vertical direction. A plurality of (four) thread guides 124 are fixed to the lateral portions of each of the slits 122, and a base 125 is fixed to the slits 122 at fixed intervals in the vertical direction.

A single balance 128 is rotatably supported by a shaft 134 at the tip of a bracket 132 attached to the upper surface of the sewing machine arm 100. A plurality of (three) thread hooks 130 are fixed to the hanging portion 129 extending downward in the balance 128 in the vertical direction at regular intervals. The hanging portion 129 is positioned so as to pass through the slit 122 corresponding to one needle bar 12 selected by the slide control of the needle bar case 10. So Figure 1
When the hanging part 129 passes through the slit 122 as shown by 5, the yarn hooking portions 130 pass between the yarn guides 124 and are located in front of the yarn guides 124. FIG.
The shaft 137 is interlocked with the rotation of the balance drive cam 103 shown in FIG.
A link 138 connects the end of the drive lever 136 that rotates around the axis of the above and the rear end of the balance body 128. Therefore, when the sewing machine main shaft 101 is rotated, the balance body 128 is reciprocally driven between the position shown in FIG. 12 and the position shown in FIG. 15 through the balance drive cam 103 and the drive lever 136.

FIG. 14 is a sectional view taken along the line AA of FIG.
As is clear from this drawing, the needle bar 12 is attached to the slider case 139 fixed to the upper part of the needle bar case 10.
The same number (six pieces) of sliders 140 are provided so as to be individually movable in the front-rear direction. A thread guide portion 141 cut in a V shape is formed at the tip of each slider 140, and a rack 142 is fixed to the lower surface of the rear end of each slider 140.

On the other hand, on the bracket 132, the rack 14 of the slider 140 corresponding to the selected needle bar 12 is attached.
A pinion 144 that meshes with 2 is rotatably supported. The pinion 144 meshes with a drive gear 148 of a motor 146 fixed to the bracket 132. Therefore, by driving the motor 146 forward and backward, the slider 14 meshed with the pinion 144 is driven.
Only 0 is controlled to move to the forward protruding position or the backward moving position. A magnet 150 for holding each slider 140 at each protruding position is fixed to the slider case 139.

In the second embodiment, as shown in FIGS. 12 and 13, the bracket 22 and the support substrate 24 are fixed to the upper surface of the slider case 139, and the same number as the needle bar 12 is provided on the support substrate 24 as in the first embodiment. Tensioning device 40
And a thread guide tension 30 is provided on the rail portion 26 of the support substrate 24.

Now, in order to set the yarn Y on the balance device 120 of the second embodiment, the yarn Y sent downward from each tension applying device 40 is guided by the yarn guide 14 of each slider 140.
1 to guide the thread guides 124 to the inner side.
Thereafter, as in the first embodiment, the thread Y guided from the thread paths 18 and 20 to the sewing needle 14 is hooked on a thread holding member (not shown) and stretched, so that the thread Y is surely attached to each thread guide 124. .
Therefore, when the sewing machine main shaft 101 is rotated, the balance body 128 reciprocates between the position shown in FIG. 12 and the position shown in FIG. 15, and when the hanging part 129 of the balance body 128 moves to the position shown in FIG. The yarn Y is pulled out by the yarn hooking portion 130 and fed out from the yarn spool of the yarn stand tray.

Next, the function of the slider 140 will be described. The slider 140 corresponding to the needle bar 12 selected by the slide control of the needle bar case 10 is held in the retracted position. Then, when the sewing with the selected needle bar 12 is completed, the sewing machine main shaft 101 is moved to the balance 128.
Stops at the position shown in FIG. When the balance body 128 starts to move toward the position shown in FIG. 12 before the main shaft 101 of the sewing machine is stopped, the motor 146 is driven and the slider 140 moves from the retracted position to the projected position, and the balance body 12
The slack of the yarn Y pulled out by 8 is absorbed.
When the needle bar case 10 is slide-controlled to select the next needle bar 12 and sewing is performed again, the sewing machine main shaft 10
1 starts to rotate and the balance 128 starts moving from the position shown in FIG. 12 toward the position shown in FIG.
46 is driven in the opposite direction. As a result, the slider 140 moves from the protruding position to the retracted position.

It is of course possible to apply the tension applying device 40 and the balance devices 80 and 120 in the above Embodiments 1 and 2 to a single needle type sewing machine, and even in that case, the time required for setting the thread can be shortened. There is no change.

[0038]

EFFECTS OF THE INVENTION The thread can be easily set on the tension applying device and the balance device.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a side surface of a sewing machine head.

FIG. 2 is a front view of the sewing machine head.

FIG. 3 is a side view of the tension applying device.

FIG. 4 is a front view of the tension applying device.

FIG. 5 is an exploded perspective view of a tension applying device.

FIG. 6 is a plan view of a tension applying device.

FIG. 7 is a side view showing a tension applying device when setting a thread.

FIG. 8 is an enlarged perspective view showing some of yarn thread tensions.

FIG. 9 is an enlarged plan view showing the balance device in a partial cross section.

FIG. 10 is a perspective view showing a part of the balance device.

FIG. 11 is a cross-sectional view showing a side surface of the sewing machine head when the needle bar is selected.

FIG. 12 is a sectional view showing a side surface of a sewing machine head according to a second embodiment.

FIG. 13 is a front view of the sewing machine head according to the second embodiment.

14 is a cross-sectional view taken along the line AA of FIG.

FIG. 15 is a sectional view showing a side surface of the sewing machine head according to the second embodiment.

[Explanation of symbols]

 14 Sewing needle 40 Tensioning device 50 Fixed thread guide 60 Movable thread guide 80,120 Balance device 86,124 Thread guide 88,128 Thread balance 91,130 Thread hooking section

Claims (3)

[Claims] 1. A sewing machine comprising a tension applying device for applying an appropriate tension to a thread supplied to a sewing needle, and a balance device for delivering a required amount of thread in synchronization with vertical movement of the sewing needle. The device is provided in at least a pair of fixed thread guides arranged at a predetermined interval in the up-down direction, and at a position separated by a predetermined distance rearward from these fixed thread guides, and passes through between the fixed thread guides. The balance device is provided with a movable thread guide that can be moved forward, and at least a pair of thread guides arranged at a predetermined interval in the vertical direction and the reciprocating movement in the front-back direction in synchronization with the vertical driving of the sewing needle. A sewing machine characterized by comprising: a balance body that repeats the above steps; and a thread hooking section that repeats passage between the thread guides by the reciprocating movement of the balance body. 2. The sewing machine according to claim 1, wherein the sewing machine is of a multi-needle type having a plurality of sewing needles, and at least tensioning devices are provided in correspondence with the number of sewing needles. And the sewing machine. 3. The sewing machine according to claim 2, wherein the balance device is single, and the sewing needle and the tension applying device selected for sewing correspond to the balance device.