JP3094990B2 - Threading sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for sewing
The present invention relates to a threading sewing machine that executes a threading operation of a sewing needle through an eye hole.

[0002]

2. Description of the Related Art Conventionally, many attempts have been made to automate a threading operation of a sewing needle into an eye hole (hereinafter, referred to as a needle-hole threading) in preparation for sewing a sewing machine. As a basic configuration of needle hole threading, for example, there is a proposal of Japanese Utility Model Publication No. 54-43878. In this proposal, a threading bar that moves up and down in parallel with a needle bar rotates at a predetermined height, thereby allowing a threading hook provided at a lower end of the threading bar to be inserted into an eye hole of a sewing needle. The operator has carried out needle hole threading by hanging the upper thread on the threading hook.

There is also a proposal that the upper thread is passed over the threading hook mechanically so as not to bother the operator. For example, JP-A-63-89194. In this proposal, a thread tension member that stretches an upper thread in front of an eye hole of a sewing needle by rotating a threading rod is described.

[0004] In performing needle hole threading using such a mechanism, the needle bar is moved to a predetermined raised position so that the threading hook or the thread tension member does not hit the presser foot or the like. Need to run through. Therefore, prior to threading the needle hole, an operation of rotating the upper shaft to raise the needle bar so that the needle bar is at a predetermined position has been performed.

[0005]

However, if the operator forgets to move the needle bar to a predetermined raised position, there is a possibility that the threading hook or the like collides with the sewing machine main body such as the presser foot or peripheral members. is there.

A threading sewing machine according to the present invention solves the above-mentioned problem, and has an object to prevent a threading means such as a threading hook from colliding with another member when performing a needle hole threading operation. I have.

[0007]

According to a first aspect of the present invention, there is provided a needle thread which is pulled out from a needle thread supply source and hung on a needle bar thread guide at a lower end of a needle bar. Needle thread arranging means for arranging the needle thread at a position crossing the front or back of the eye hole of the sewing needle, and lowering the threading rod to take the arranged upper thread into the eye hole to perform a threading operation. and a threading means for performing, in threading the sewing machine in which the yarn is passed through the eye hole by the threading means, through said thread
Prior to the lowering of the rod, separating means for separating the sewing needle from the surrounding members, first determining means for determining whether the threading sewing machine is under sewing control, and the first determining means When it is determined that the sewing control is being performed, the first prohibiting means for prohibiting the operation of the threading means is provided.
When the threading operation is prohibited, the threading means is operated again.
If it is not made, the system will not perform separation by the separation means.
And control means .

In the threading sewing machine of the present invention, the threading
Prior to the lowering of the rod , the separating means separates the sewing needle from the surrounding members. When the sewing needle and the surrounding members are separated in this way, the threading means does not collide with other members when performing the threading operation.

As a result, the threading means can execute the threading of the sewing needle into the eye hole, and does not hit the sewing machine main body or peripheral members. Further, in the present invention, it is determined by the first determination means whether or not the threading sewing machine is under sewing control,
When it is determined that the sewing control is being performed, the first prohibiting means prohibits the operation of the threading means. And said
When the threading operation is prohibited by the first prohibiting means,
If the threading means is not operated, the separating means
There is no pause.

According to a second aspect of the present invention, the tip side of the upper thread pulled out from the upper thread supply source and hung on the needle bar thread guide at the lower end of the needle bar is moved to a position crossing the front or back of the eye hole of the sewing needle. An upper thread disposing means for disposing , and a threading means for lowering a threading rod, taking in the disposed upper thread into an eye hole, and executing a threading operation; in threading the sewing machine in which the yarn is passed through the eye hole by threading means, said yarn passage
Separation means for separating the sewing needle and its surrounding members prior to the lowering of the push rod, second judgment means for judging whether or not the presser foot of the threading sewing machine is raised; and second judgment means. when There determines that it has not the rise, and a second inhibiting means for inhibiting the operation of said threading means, said second forbidden hand
When the threading operation is prohibited by the step, the threading means is again
If the is not operated, do not perform separation by the separation means.
And control means .

In the present invention, similarly to the first aspect of the present invention, the separating means separates the sewing needle from the peripheral members prior to the lowering of the threading rod . Therefore, the threading means does not collide with other members when performing the threading operation.
Further, in the present invention, it is determined whether or not the presser foot of the threading sewing machine is raised by the second determining means. Operation is prohibited. And the second prohibited hand
When the threading operation is prohibited by the step, the threading means is again
Is not operated, the separation by the separation means is performed.
Absent.

According to a third aspect of the present invention, the leading end of the upper thread pulled out from the upper thread supply source and hung on the needle bar thread guide at the lower end of the needle bar is moved to a position crossing the front or back of the eye hole of the sewing needle. A threading machine comprising: an upper thread disposing means for disposing ; and a threading means for lowering the threading rod, taking in the disposed upper thread into the eye hole, and executing a threading operation. A separating means for separating the sewing needle and a member therearound prior to lowering of the threading rod; a first determining means for determining whether or not the threading sewing machine is under sewing control; (1) When the determination means determines that the sewing control is being performed, a first inhibition means for inhibiting the operation of the threading means, and a second determination for determining whether or not the presser foot of the threading sewing machine is raised. Means, when the second determination means determines that the thread has not risen, A second inhibiting means for inhibiting the operation of the means, and threading by the first inhibiting means or the second inhibiting means
If the operation is prohibited, the threading means must be operated again.
Then, there is provided a control unit that does not perform separation by the separation unit .

That is, the present invention has both the structure of the invention described in claim 1 and the structure of the invention described in claim 2. Therefore, the operation and effect corresponding to the first aspect and the operation and effect corresponding to the second aspect occur simultaneously. And the first prohibiting means or the second prohibiting hand.
When the threading operation is prohibited by the step, the threading means is again
Is not operated, the separation by the separation means is performed.
Absent.

According to a fourth aspect of the present invention, in addition to the configuration of any one of the first to third aspects, a third determining means for determining whether or not the needle bar is raised by a predetermined amount or more, (3) a third prohibition unit that prohibits the operation of the threading unit when the determination unit determines that the threading unit does not rise. For this reason, in addition to the effect of the invention according to any one of claims 1 to 3, it is determined by the third determining means whether or not the needle bar has risen by a predetermined amount or more, and it is determined that the needle bar has not risen. When the operation is performed, the third prohibiting means prohibits the operation of the threading means.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. The sewing machine according to the present embodiment is a fully automatic threading threader that has a function of automatically executing threading to a balance section (hereinafter referred to as “balance threading”) in addition to needle hole threading. is there.

FIG. 1 is a perspective view of a sewing head 1 of a fully automatic threading threader when viewed from a face plate 3 direction. On the upper portion of the sewing machine head 1, a thread stand 5 and an upper thread hook 9 for turning an upper thread w drawn out from a thread spool 7 attached to the thread stand 5 to the front side are provided. Further, the sewing head 1 is turned right before the upper thread hook 9 across the upper surface to the front, descends from the upper front to the lower portion, and
There is provided a guide groove 11 which reaches the rear surface after passing through the lower front surface.

On the front side of the sewing machine head 1, a push button switch SW is provided one by one up and down with the guide groove 11 therebetween.
1 and SW2 are provided. The lower switch SW1 is a start switch for instructing the start of sewing, and the upper switch SW2 is a threading switch for instructing execution of a balance thread hook and needle hole threading, which will be described later. Hereinafter, SW1 is referred to as a start switch, and SW2 is referred to as a threading switch.

As shown in FIG. 2, the guide groove 11 passes between two plates 15-15 of the thread tension plate 13 when viewed from the front.
A path which obliquely crosses the vicinity of the middle of the yarn path 17 above the yarn take-up spring 19, descends and winds the needle bar yarn guide 23 provided at the lower part of the needle bar 21, and smoothly curves the lower front portion of the face plate 3. None, and it also wraps around the back by a predetermined amount. The end point 25 of the guide groove 11 that has turned around to the back
Is equipped with a thread cutting cutter 27.

A balance 30 that swings up and down on the front side of the thread path 17 is provided inside the sewing machine head 1 at the front portion of the guide groove 11. The balance 30 is provided at the tip portion as shown in FIG.
As shown in (c), a claw 31 bent upward from below so that the upper thread w can be scooped up, a covering rod 32 disposed so as to cover the claw 31, and this covering. Rod 32
And a presser cover 33 fixed to the cover. Then, as shown in FIG. 3A, the slightly elongated slender thread holding hole 3 is formed by the hooks 31 and the presser cover 33 as shown in FIG.
4 are formed.

As shown in FIG. 3B, the presser cover 33 has a U-shaped cross section that crosses the yarn path 17 when viewed from above, and includes a front plate 35 located in front of the yarn path 17. It comprises a rear plate 36 located on the rear side, and a connecting plate 37 for connecting the two plates 35, 36 on the front side of the yarn path 17.

The tip of the hook 31 overlaps with the front plate 35 and is slightly bent toward the yarn path 17 as shown in FIG. On the other hand, as shown in FIG.
A notch 38 is formed so that the tip of the claw 31 is exposed. As shown in FIG. 4, the balance 30 is swingably mounted on a sub shaft 41 disposed in parallel with the upper shaft 40, and includes a base 43 having a cam hole 42 formed near the mounting portion. . A crank pin 45 of a balance crank 44 fixed to the upper shaft 40 is inserted into the cam hole 42.
The cam hole 42 is formed at a central arc portion 46 having a curvature substantially equal to the rotation radius of the crank pin 45, a straight portion 47 formed at an end on the counter shaft 41 side, and at another end. And a short arc portion 48 having a small curvature.
Rotates the balance 30 in an arc as shown by the arrow in the figure. In this circular motion, the balance 30 moves as shown in FIG.
The mounting relationship between the cam hole 42 and the crank pin 45 is determined so that the cam hole 42 can swing to a position beyond the lower end 50 of the yarn path 17 as indicated by the one-dot chain line in FIG.

On the other hand, at the lower end 50 of the yarn path 17, a yarn receiver 52 having a concave portion 51 which is concave upward is provided. At a position facing the recess 51 of the thread receiver 52, a pressing roller 53 is provided so as to be able to approach and separate. At the time of sewing, the pressing roller 53 is driven by a cam mechanism (not shown).
It functions to adjust the tension of the upper thread w by approaching and separating from the thread receiver 52. A guide member 55 is disposed at an intermediate portion between the balance 30 and the thread receiver 52 so as to wind the thread take-up spring 19 and the thread path 17.

The lower end of the threading bar 60 arranged in front of the needle bar 21 is located at the curved portion of the guide groove 11 toward the face plate 3 ahead of these balance portions. This threading rod 6
0 will be described.

As shown in FIG. 5, a frame 61 for supporting the needle bar 21 is mounted inside the face plate 3, and the threading bar 60 moves up and down on an axis parallel to the needle bar 21. The frame 61 is rotatably supported by the frame 61. At the lower part of the threading rod 60 supported by the frame 61, a guide mechanism and a link mechanism, which will be described later, are operated by the vertical movement and rotation of the threading rod 60, so that the threading rod 60 is in front of the eye 63 of the sewing needle 62. A thread tension member 64 for stretching the upper thread w, and a threading member 65 for taking the stretched upper thread w into the eye hole 63 are attached.

First, the structure of the thread tension member 64 will be described.

As shown in FIG. 6A, the thread tension members 64 are arranged at substantially the same height so as to wrap around from the side close to the needle bar thread guide 23 toward the front of the sewing machine head 1 to the rear side. First threaded portion 66, second threaded portion 67 disposed
And the third threaded portion 68 and these three threaded portions 6
6, 67, 68 and a yarn end holding member 70 which is disposed at a position slightly further away from and further behind.

The needle bar 21 is provided below the first thread tension portion 66.
A thread hooking claw 71 projecting to the side is formed. At a lower portion of the second threading portion 67, a holding claw 72 is formed slightly above the thread hooking claw 71 of the first threading portion 66 and protruding forward from the first threading portion 66. Have been. Further, a pressing piece 73 is formed on the upper portion of the third threading portion 68 so as to be aligned with the pressing claw 72 of the second threading portion 67 and project to the front side at substantially the same height as the pressing claw 72. I have.

Of these, the first and second threaded portions 66,
As shown in FIG. 6B, 67 is formed integrally by bending a single plate material into a substantially “B” cross section. The arrangement relationship between these two thread tension portions 66 and 67 will be described in detail.
The second threading portion 67 is provided with the first threading portion 66 so that the two threading portions 66 and 67 partially overlap as viewed from the front.
Is spaced slightly behind by a predetermined gap 74.
The first and second thread tension portions 66 and 67 are directly attached to a metal bracket 75 having a U-shaped cross section which is rotatably attached to the threading rod 60.

The third thread tension portion 68 is formed at the free end of a rotating arm 77 whose one end is fitted to the threading rod 60 and is prevented from rotating by a pin 76.

Furthermore, when the upper thread w is guided, the thread end holding member 70 supports the upper thread w from below.
0 and a holding plate 82 slidably attached to a support column 81 erected on a receiving plate 80. This holding plate 82
Is urged downward by a spring 83 attached to the support column 81. In addition, in the vicinity of the support column 81 of the receiving plate 80,
One receiving groove 84 extending in the tangential direction of the support column 81 is formed.

The thread end holding member 70 is provided with a support shaft 8 erected downward at the end of an arm 80a extending from the receiving plate 80.
0b, it is rotatably supported by the third threaded portion 68.

On the other hand, one end of the above-mentioned "U" -shaped bracket 75 has a deformed pin 85 having a large diameter portion at the center in the longitudinal direction.
Is loosely fitted. The thread end holding member 70 is connected to the “U” -shaped bracket 75 by a connection lever 86 whose ends are loosely fitted to the deformed pins 85 and the columns 81. The support column 81 is slidably engaged with a guide groove 88 formed on the lower surface of a slide guide 87 that is loosely fitted to the threading rod 60.

The sliding guide 87 is vertically fixed to the threading rod 60 by an E-shaped retaining ring E, and is framed through a groove 89 having a U-shaped cross section, which is vertically disposed from the upper surface. It is slidably engaged with a pin 61a protruding horizontally below the body 61. The sliding guide 87 serves as a guide for vertically moving the threading rod 60 by means of a "U" -shaped groove 89, and also serves to guide the column 81 in the horizontal direction via a guide groove 88 on the lower surface. Also plays.

Next, the structure of the threading member 65 will be described.
As shown in FIG. 7, the threading member 65 is attached to the back of the rotating arm 77, extends rightward in the figure, and is bent to the front side. And two hook guards 91 provided. As shown in FIG. 8, a guide groove 93 is formed at the tip of each hook guard 91 toward the downward hook 92 of the tip of the threading hook 90.

The thread tension member 64 and the threading member 65 thus configured operate at a predetermined position at a predetermined timing by the vertical movement and rotation of the threading bar 60. The vertical movement and the turning operation will be described together with the mechanism. As shown in FIG. 5, a guide member 95 arranged to cover the upper part of the threading bar 60 is slidably attached to the threading bar 60 as shown in FIG. The guide member 95 has a rotating cam hole 96 formed of a long hole obliquely engraved at a predetermined upper position.
The threading rod 60 is provided with an engagement pin 9
7 is engaged with the rotating cam hole 96 via one end.
The threading member 60 is urged from above by a spring 98 attached between the top plate of the guide member 95 and the engagement pin 97. As a result, the engagement pin 97 is normally in contact with the lower end of the rotating cam hole 96.

The guide member 95 is connected to a spring 99 mounted on the upper portion of the frame body 61.
Urged upwards. A pressing plate 101 provided on an upper end of a rack 100 that slides in parallel with the threading rod 60 is in contact with an upper end of the guide member 95 from above. The rack 100 is driven up and down by dedicated pulse motors 105 via gears 102 to 104.

When the rack 100 is lowered, the threading rod 60
Is lowered together with the guide member 95, and stops at that position when the left end side of the engagement pin 97 in the figure comes into contact with the contact member 106 attached to a predetermined position of the needle bar 21. Contact member 1
06 is determined in consideration of the position of the eye hole 63 of the sewing needle 62, and at the stop position of the threading rod 60, the threading hook 90 of the threading member 65 matches the height of the eye hole 63. It is made to do. When the rack 100 further descends, the engagement pin 97 slides along the cam hole 96, and the threading rod 60 rotates. By this pivoting operation, the thread tension member 64 and the threading member 65 are moved from FIG.
Rotate as shown in (c).

When the threading rod 60 rotates clockwise in the drawing, the rotating arm 77 rotates clockwise integrally with the threading rod 60. Then, the receiving plate 80 is pushed to the left in the drawing, and the support column 81 slides in the guide groove 88 to the left in the drawing. Along with this, the “U” -shaped bracket 75 is rotated counterclockwise in the drawing with respect to the threading rod 60 by being pulled by the connecting lever 86. As a result, as shown in FIG.
4, the distance between the first and second thread tension portions 66, 67 and the thread end holding member 70 is maximized, and the threading hook 90 is inserted into the eye hole 63 of the sewing needle 62. When the threading rod 60 is rotated in the opposite direction from this state, the threading rod 60 is rotated as shown in FIG.
As shown in FIG.
Returns to the contracted state.

Next, the procedure for preparing the upper thread w through the guide groove 11 will be described with reference to FIGS.
This will be described with reference to (a).

First, the presser foot lever 112 disposed on the rear side of the needle bar 21 of the sewing machine head 1 is operated to operate the presser foot 112.
To open the thread tension tray 13. Next, thread spool 7
, The upper thread w is pulled out from the upper thread hook 9 and then guided along the guide groove 11 from the front to the back. Then
The upper thread w is guided between the plates 15 and 15 of the thread tension tray 13 on the front side of the sewing machine head 1, hangs on the thread take-up spring 19 from above, and then hangs on the needle bar thread guide 23, and then the first thread The hook is hooked on the thread hook 71 of the tension portion 66, and further passes directly below the holding claw 72 of the second thread portion 67, and from below onto the holding piece 73 of the third thread portion 68. After that, it enters between the receiving plate 80 of the thread end holding member 70 and the presser tray 82, further wraps around, and is cut by the cutter 27.

FIG. 9A shows the state in which the upper thread w is prepared on the thread tension member 64 in this manner. Upper thread w is guide groove 1
As it goes around to the end point 25 of 1, as shown in the figure,
The support 81 is held by the thread end holding member 70 so as to bite into the root portion. The upper thread w has some slack as a whole along the guide groove 11.

Next, the configuration of a control system of the fully automatic threading threader will be described with reference to FIG.

The control system of the fully automatic threading threading sewing machine includes a CPU, a ROM, a RAM, and the like, and is mainly configured by an electronic control circuit 120 that controls the threading of the balance, the threading of the needle hole, and the sewing. The input side of the electronic control circuit 120 is connected to a start switch SW1 and a threading switch SW2, and the output side is connected to a sewing machine motor 125 and a pulse motor 105 via a sewing machine motor driver 122 and a pulse motor driver 124. . In addition, the electronic control circuit 120 has an NP1 sensor 130 that sends out a detection signal when the needle bar is at the uppermost position (hereinafter referred to as NP1) from the phase angle of the upper shaft 40, and when the balance is at the uppermost position (hereinafter referred to as NP2). An NP2 sensor 132 that sends out a detection signal is connected. Further, the electronic control circuit 120 includes a presser foot upper position sensor 134 for sending a detection signal when the presser foot 112 is raised in cooperation with the presser foot lever 110, that is, when the thread tension disc 13 is in an open state. As shown in the figure, a threading confirmation sensor 136 that is attached to the top of the guide member 95 of the threading bar 60 and that operates when the upper end of the threading bar 60 projects a predetermined amount or more and sends out a detection signal is connected. .

Next, control processing executed by the electronic control circuit 120 will be described. 11 and 12 show flowcharts of the control processing.

As described above, the upper thread w is pulled out from the thread spool 7 and guided to a predetermined position along the guide groove 11. When the power is turned on to the sewing machine, first, initialization is executed, and the origin of the pulse motor 105 and other various motors is set (step 1; hereinafter, each step is simply referred to as S).

Next, it is determined whether or not the threading switch SW2 is depressed and turned on (S2). When the threading switch SW2 is turned on, the process proceeds to the next step, and it is determined whether or not the activation switch SW1 is off (S3). If it is determined in this processing that the activation switch SW1 is in the off state, it is determined whether the presser foot 112 is in the upper position, that is, whether the thread tension disc 13 is in the open state (S).
4). If the activation switch SW1 is in the ON state or the presser foot 112 is not raised, the process does not proceed to the following process but returns to S2. That is, the threading switch SW2 is a switch that operates momentarily, and if S3 or S4 is negative, the following processing is not executed unless it is pressed again.

On the other hand, only when the start switch SW1 is in the off state and the presser foot 112 is at the upper position, the process proceeds to the next processing to drive the sewing machine motor 125 (S5).
When the sewing machine motor 125 is driven, the upper shaft 40 rotates. With the rotation of the upper shaft 40, the balance crank 44 also rotates, and the balance 30 is swung to start the balance thread hooking. Needle bar crank 142 connected to crank pin 45
Converts the rotational movement of the balance crank 44 into a vertical reciprocating motion, and transmits the reciprocating motion to the needle bar 21 via the needle bar holder 144. As a result, the needle bar 21 is moved up and down.

The sewing machine motor 125 is stopped after confirming whether or not the upper shaft 40 has made one rotation or more and whether or not the phase angle of the upper shaft 40 has become NP1 and the NP1 sensor 130 has output a detection signal (S6). , S7, S8). In the present embodiment, the phase angle of the upper shaft 40 is NP in the process of S7.
When the sewing machine motor 125 is stopped after confirming that the number has become 1, the threading member 65 and the like are prevented from colliding with the presser foot 112 and other members when executing the needle hole threading operation described later. doing. That is, the sewing machine motor 12
Electronic control circuit 120 storing the processing of S5 and S5 to S8
ROM corresponds to the separating means of the present invention. Further, in the present embodiment, the ROM of the electronic control circuit 120 storing the determination processing in S3 is used as the first determination means of the present invention.
The ROM of the electronic control circuit 120 storing the processing for shifting from S3 to S2 is the ROM of the electronic control circuit 120 storing the determination processing in S4 as the first prohibiting means of the present invention.
The ROM of the electronic control circuit 120 storing the process for shifting from S4 to S2 is stored in the second determining means of the present invention, and the ROM of the electronic control circuit 120 storing the determining process in S7 is stored in the second inhibiting means of the present invention. The ROM corresponds to the third determining means of the present invention, and the ROM of the electronic control circuit 120 storing the processing for shifting from S7 to S5 corresponds to the third inhibiting means of the present invention.

A description will now be given of the balance thread hooking executed during the above-described steps S5 to S8. As shown in FIGS. 13A to 13C, when the balance 30 is swung down, the guide grooves 11
The pressing cover 33 at the tip of the balance 30 abuts on the upper thread w prepared across substantially the center of the thread path 17 along the line. At this time, the upper thread w is in contact with the lower surfaces of the front plate 35 and the rear plate 36 of the presser cover 33 as shown in FIG. Become. Balance 3
No. 0 is further lowered downward while being in contact with the upper thread w, and the upper thread w is drawn out along the thread path 17.

At this time, the upper thread w is drawn out from both the upstream side and the downstream side. However, the end of the upper thread w is held by being sandwiched by the thread end holding member 70, while the thread tension disc 13 is in an open state, so that the upper thread w is swung to the extent that there is no slack on the downstream side. The required amount is drawn from the upstream side.

The balance 30 is further lowered to reach a position beyond the lower end 50 of the yarn path 17. Then, the front plate 35 and the rear plate 36
The thread path 17 that has prevented the upper thread w from dropping into the thread holding hole 34 in the middle is eliminated. Further, the upper thread w is pulled obliquely upward by the positional relationship between the thread tension tray 13 and the tip of the balance 30 and the spring-up operation of the thread take-up spring 19. As a result, the upper thread w comes off the notch 38 of the presser cover 33, enters the recess 51 of the thread receiver 52, and hangs on the inner part of the thread holding hole 34. The inside of the yarn holding hole 34 is the yarn path 1
Since the balance 30 is located above the lower end portion 50 of the balance 7, even if the balance 30 swings upward from this state, the balance 30 does not cross the lower end portion 50 again.

As described above, the thread receiver 52 and the balance 30
Of the thread on the thread holding hole 34 is completed.

During this time, the needle bar 21 reciprocates up and down transmitted through the needle bar crank 142 as described above.

Here, as shown in FIG. 2, the upper thread w guided along the guide groove 11 is hooked on the needle bar thread guide 23 and then passed to the left in the figure. Therefore, when the needle bar 21 starts to descend, the upper thread w is pushed downward by the needle bar thread guide 23. At this time, as described above, since the end of the upper thread w is held by the thread end holding member 70, the upper thread w is pulled out from the upstream side by about twice as much as the downward movement of the needle bar thread guide 23. At this time, the upper thread w is in a state of being stretched by the needle bar thread guide 23, and no slack has occurred. Therefore, the state of being initially guided by the thread tension member 64 is maintained.

On the other hand, when the needle bar 21 is raised, the needle bar thread guide 23 is raised with little force applied to the upper thread w. For this reason, the extra upper thread w pulled out when the needle bar 21 descends remains as slack on the thread tension member 64 side in this state. However, since the vertical swing of the balance 30 and the vertical movement of the needle bar 21 are interlocked, the balance 30 is swung down when the needle bar 21 is lowered, and the balance 30 is swung when the needle bar 21 is raised. It is being swung up. Accordingly, as described above, the surplus upper thread w which is pulled out by the needle bar thread guide 23 is left.
As shown by a dashed line in FIG. 13 (a), with the raising operation of the balance 30 performed along with the raising of the needle bar 21, the claw 31 raises it.

Therefore, in the vicinity of the thread tension member 64,
No slack of the upper thread w remains. As a result, the same state as initially guided along the guide groove 11 is maintained in the thread tension member 64, and the needle bar 21 is stopped at the uppermost position (S
7, S8). Next, the pulse motor 105 is rotated forward (S
9). Note that “the pulse motor 105 rotates forward” means
This refers to a case where the rack 100 is driven in a direction of descending.

When the pulse motor 105 is rotated forward, FIG.
(A) to (c) and FIGS. 14 (a) to (c),
Needle hole threading is performed. The operation will be described.
When the pulse motor 105 is rotated forward, the threading rod 60 descends as described above. When the threading hook 90 is at the same height as the eye hole 63, the threading bar 60 rotates at that height.
As a result, as shown in FIG. 9B, when the thread tension member 64 is in the expanded state, the first and second thread tension portions 66 and 67 are rotated to a position beyond the sewing needle 62.

At the time of the expanding operation, the end of the upper thread w is
Since the needle thread w is held by the thread end holding member 70, the needle thread w is mainly pulled out from the upstream side, and is stretched over the front of the eye 63 of the sewing needle 62. At this time, the upper thread w
Into the lower side of the first threaded portion 66 through the
3 is in a state of almost abutting.

In a state where the upper thread w is in contact with the eye 63, that is, in the thread tensioning operation by the thread tension member 64, the upper thread w
Is in a state of being stretched between the second thread tension portion 67 and the thread end holding member 70. Moreover, when the thread tension member 64 is expanded, the thread end holding member 70 moves straight to the left along the guide groove 88 as shown in FIGS. 9 (a) and 9 (b). Accordingly, the thread end holding member 70 draws out the upper thread w from the needle bar thread guide 23 side by this large stroke to the left in the figure. As a result, even when the slack of the upper thread w cannot be completely absorbed when the balance 30 is swung up, the remaining slack is eliminated by this large stroke.

In this manner, at the same time that the thread tensioning operation is performed by the thread tensioning member 64, the threading member 65 is rotated clockwise in the drawing. As a result, the threading hook 90
As shown in FIG. 14A, the upper thread w is projected to the front side through the eye hole 63, and the upper thread w is hooked on the downward hook 92 through the guide groove 93 of the hook guard 91.

It is confirmed by the ON signal of the threading confirmation sensor 136 whether or not the upper thread w is hooked on the threading hook 90 inserted through the eye 63 (S10). When the threading confirmation sensor 136 is turned on, the timer is set and the pulse motor 105 continues to rotate forward until a predetermined time has elapsed (S12). This processing is performed by the upper thread w
Is taken into consideration in some cases that the upper thread w is not hooked on the threading hook 90, and the next operation is performed after the upper thread w is securely hooked on the threading hook 90.

After a lapse of a predetermined time, the pulse motor 105 is rotated reversely (S13). At this time, the number of pulses C required for the forward rotation is stored in a predetermined memory area in the electronic control circuit 120. Pulse motor 105
Is reversed, the threading rod 60 rotates, and FIG.
As shown in FIG. 7, the thread tension member 64 returns to the contracted state, the threading member 65 also rotates, and the threading hook 90
Escapes. When the threading rod 60 further rotates and the engaging pin 97 contacts the lower end of the rotating cam hole 96, this rotation stops, and the threading rod 60 moves up together with the guide member 95 this time.

As a result, as shown in FIGS. 14B and 14C, the upper thread w caught on the threading hook 90 is
And is pulled out. At this time, the yarn end of the upper thread w moves outward from the surface of the support column 81 and moves along the groove 84 into the receiving plate 8.
It falls off from between 0 and the presser plate 82.

The pulse motor 105 is rotated backward by the number of pulses corresponding to the pulse number C at the time of normal rotation stored immediately before the reverse rotation, and stopped (S14, S15). As a result, the balance thread hooking and the needle hole threading are completed.
Is pressed and turned on, sewing control is started (S16).

When the sewing control is instructed, first, the presser foot 11
It is determined whether or not 2 is lowered (S17). If the presser foot 112 is at the upper position, the process returns to S16 and sewing is not started. On the other hand, when the presser foot 112 has been lowered, the sewing machine motor 125 is driven to perform sewing (S18). The sewing by the sewing machine motor 125 is continued until the start switch SW1 is pressed again to be turned off (S19).

When the start switch SW1 is depressed and turned off, the sewing machine motor 125 is stopped after the detection signal is transmitted from the NP2 sensor 132 (S20, S21).

As a result, the upper shaft 40 stops in a state where the balance 30 is swung up to the uppermost position, that is, a state where the needle bar 21 is also raised and the sewing needle 62 is pulled out of the cloth, and the thread is pulled out from the thread hook (not shown). It runs smoothly.

As described above, according to the present embodiment, the needle bar 21 is raised to the vicinity of the uppermost position prior to the needle hole threading. Therefore, the thread tension member 64 and the thread The threading member 65 does not collide with members around the sewing needle 62 such as the presser foot 112. In addition, since the balance thread hooking is performed in parallel with raising the needle bar 21 to the vicinity of the uppermost position, the extra thread amount generated when the needle bar 21 descends is measured by the balance 3.
It can be absorbed by the swing-up operation of zero. Therefore, although the upper thread w is pulled out with the lowering of the needle bar 21, the drawn upper thread w does not sag and fall off from the claws 71, 72, etc. of the thread tension member 64. . As a result, the upper thread w is stretched over the eye 63 of the sewing needle 62 in the predetermined tension state by the subsequent thread tension operation by the thread tension member 64.

From this, at the time of threading the needle hole, the threading member 65 or the like operates smoothly without colliding with the presser foot 112 or the like, and moreover, the threading hook 92 inserted through the eye hole 63 reliably. The upper thread w can be hooked. As a result, the needle hole threading can be reliably performed.

In this embodiment, the yarn end holding member 7
The upper thread w is stretched between the zero and the second thread tension portion 67 to be in a tension state, and the thread end holding member 70 pulls the upper thread w from the upstream side with a large stroke to perform the thread tensioning operation. Since it is executed, even if it is not possible to sufficiently absorb the slack of the upper thread w by the balance thread hooking operation, there is a capacity to absorb a considerable amount of the remaining slack, and the upper thread w is surely held in a predetermined tension state. You can overtake. Furthermore, according to the yarn end holding member 70 that moves with a large stroke, even in an experiment in which the slack is not absorbed by the balance yarn hook, the upper stroke generated by the vertical movement of the needle bar 21 due to this large stroke operation. It has been confirmed that the slack of w can be sufficiently absorbed.

As described above, the slack absorbing means is the needle bar thread guide 2
The yarn end holding member 70 is not limited to the upstream side but may be downstream. Furthermore, if the slack is absorbed both upstream and downstream of the needle bar thread guide 23 as in the present embodiment, the slack is almost completely eliminated, and the needle hole threading hardly fails.

In addition, according to the present embodiment, the needle thread threading is performed by applying the upper thread w to the needle bar thread guide 23. Therefore, when the threading of the needle thread is completed, the sewing is immediately performed as it is. Can start. In addition, instead of the configuration of the present embodiment, a configuration may be adopted in which a slack is absorbed by using an upper thread supply motor such as an automatic thread tension sewing machine, or a configuration may be adopted in which a dedicated motor for absorbing the slack is newly provided. It is.

In the present embodiment, the upper thread w is
3 is applied to the front of the eye hole 3 in a predetermined tension state, but it is arranged in a state where it is slack at the front or back of the eye hole 63, and the arranged upper thread w is aired or the like. The present invention can also be applied to a sewing machine having a needle hole threading device configured to blow air into the sewing machine. Even with such a sewing machine, the upper thread w
If it loosens, the upper thread cannot be aimed at the eye hole, and the needle thread threading fails. However, as in the present embodiment, this problem can be solved by executing the slack absorption prior to the threading. The slack absorbing operation of the sewing machine having this configuration is executed not only by simply absorbing the slack, but also by re-arranging the upper thread in front of the eye hole. In the present invention, the term “sag absorption” includes such a case.

Further, the rising position of the needle bar is not limited to the vicinity of the uppermost position. If, for example, the presser foot 112 is lowered to perform needle hole threading, it is not necessary to raise the needle bar to the vicinity of the uppermost position. Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, the threading hook 90 may be configured to push in the upper thread w instead of pulling the upper thread w into the eye hole 63. Various modes can be adopted without departing from the gist.

[0075]

As described above, according to the present invention, the yarn
Prior to the lowering of the pass-through bar , the separating means separates the sewing needle from the surrounding members. When the sewing needle and the peripheral members are separated in this way, the threading means does not collide with the sewing machine main body, peripheral members, and the like. Therefore, the needle hole threading can be smoothly performed.

According to the first aspect of the present invention, the operation of the threading means is inhibited while the threading sewing machine is under sewing control. According to the second aspect of the present invention, when the presser foot is not raised, The operation of the threading means is prohibited, and in the invention according to claim 3, the operation of the threading means is prohibited in any case. Further, in the invention according to the fourth aspect, the operation of the threading means is prohibited even when it is determined that the needle bar has not risen by a predetermined amount or more.

Therefore, collision of the members is avoided, and
Needle hole threading can be performed. And threading movement
If the operation is prohibited, the threading means must be operated again.
For example, separation by the separation means is not performed without permission.

As a result, the sewing machine of the present invention is extremely easy to handle, and can reliably perform needle-hole threading.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an appearance of an embodiment.

FIG. 2 is a front view showing the configuration of the guide groove.

3A is a front view of the balance unit, FIG. 3B is a partial plan view thereof, and FIG. 3C is a partial rear view thereof.

FIG. 4 is an explanatory view showing the swinging operation of the balance.

FIG. 5 is a rear view of the inside of the sewing machine head showing the configuration of the needle bar and the threading bar.

FIG. 6A is a perspective view of a thread tension member provided at the lower end of the threading rod, and FIG. 6B is a cross-sectional view of the thread tension member in an expanded state.

FIG. 7 is a plan view of a part of a thread tension member and a threading member.

FIG. 8 is a partial side view of the threading member.

FIGS. 9A to 9C are plan views showing the thread tensioning operation of the thread tensioning member.

FIG. 10 is a block diagram illustrating a configuration of a control system according to the embodiment.

FIG. 11 is a flowchart of a control process executed by the control system.

FIG. 12 is a flowchart showing the continuation of the control process.

FIGS. 13A to 13C are explanatory diagrams illustrating the threading operation of the balance.

14A and 14B are perspective views showing a threading operation of a threading member, and FIG. 14C is a sectional view of the same.

[Explanation of symbols]

w ... upper thread 7 ... thread spool 9 ... upper thread hook 11 ... guide groove 21 ... needle bar 23 ... needle bar thread guide 30 ... balance 60 ... threader bar
62 ... sewing needle 63 ... eye hole 64 ... thread tension member 65 ... threading member 70 ... thread end holding member 88 ... guide groove 105 ... pulse motor 110 ...
Presser foot lever 120: Electronic control circuit 125: Sewing machine motor 1
30 ... NP1 sensor

Claims (4)

(57) [Claims] An upper thread for arranging a distal end side of an upper thread pulled out from an upper thread supply source and hung on a needle bar thread guide at a lower end of a needle bar at a position crossing the front or back of an eye hole of a sewing needle. A thread disposing means, and a threading means for lowering the threading rod , taking the disposed upper thread into the eye hole, and performing a threading operation, wherein the thread is passed by the threading means. In a threading sewing machine that is passed through an eye hole, a separation unit that separates the sewing needle and a member around the sewing needle prior to the descent of the threading rod; and determining whether the threading sewing machine is under sewing control. a first determining means, when the first determining means determines to be in the sewing control, a first inhibiting means for inhibiting the operation of said yarn-threading device, the threading operation by the first inhibiting means prohibited If done,
If the threading means is not operated again, the separating means
And a control unit that does not perform separation . 2. An upper end for arranging a tip end side of an upper thread pulled out from a needle thread supply source and hung on a needle bar thread guide at a lower end of a needle bar at a position crossing the front or back of an eye hole of a sewing needle. A thread disposing means, and a threading means for lowering the threading rod , taking the disposed upper thread into the eye hole, and performing a threading operation, wherein the thread is passed by the threading means. In a threading sewing machine that is passed through an eye hole, a separation unit that separates the sewing needle and a member around the sewing needle prior to the descent of the threading rod; and whether a presser foot of the threading sewing machine is raised. A second judging means for judging, and when the second judging means judges that the rise has not occurred,
A second prohibition unit that prohibits the operation of the threading unit; and a case where the threading operation is prohibited by the second prohibition unit.
If the threading means is not operated again , the separating means
And a control unit that does not perform separation . 3. An upper end for disposing a tip end side of an upper thread pulled out from an upper thread supply source and hung on a needle bar thread guide at a lower end of a needle bar at a position crossing the front or back of an eye hole of a sewing needle. A thread disposing means, and a threading means for lowering the threading rod , taking the disposed upper thread into the eye hole, and performing a threading operation, wherein the thread is passed by the threading means. In a threading sewing machine that is passed through an eye hole, a separation unit that separates the sewing needle and a member around the sewing needle prior to the descent of the threading rod; and determining whether the threading sewing machine is under sewing control. A first judging means for performing, a first prohibiting means for prohibiting the operation of the threading means when the first judging means judges that the sewing control is being performed, and a presser foot of the threading sewing machine rises. Second determining means for determining whether or not there is a When the intended decision,
A second prohibiting device for prohibiting the operation of the threading device; and a threading operation performed by the first prohibiting device or the second prohibiting device.
If prohibited, unless the threading means is operated again,
A threading sewing machine comprising: a control unit that does not perform separation by the separation unit . 4. A third determining means for determining whether or not the needle bar has risen by a predetermined amount or more, and when the third determining means determines that the needle bar has not risen,
The threading sewing machine according to any one of claims 1 to 3, further comprising: a third prohibiting unit that prohibits the operation of the threading unit.