JPH03143486A - Threading device - Google Patents

Abstract

PURPOSE:To enable thread to be largely led out of an eye hole without bending a sewing needle by setting an elastic member to be energized inside the opening section of a threading hook, and by setting a blocking member for blocking the elastic member to be brought in contact with the sewing needle, on a bearing body. CONSTITUTION:According to the movement of a wire 86 in the rear surface direction of an eye hole 18a, on a second link section 70b for moving in the front surface direction of the eye hole 18a, on its base section, a plate member 88 is fitted. The plate member 88 is set at a position brought in contact with the central section 86c of the wire 86, when a threading hook 72 and the second link section 70b are confronted with each other and are moved in the direction of the eye hole 18a, and immediately before the wire 86 is brought in contact with a sewing needle 18. In order words, when the threading hook 72 is thrust into the eye hole 18a, then the wire 86 energized inside 72a its opening section is blocked to be brought in no contact with the sewing needle 18. When the threading hook 72 is thrust into the eye hole 18a up to a specified position in a state that the wire 86 is blocked to be brought in no contact with the sewing needle 18, in this manner, then thread 68 stretched on the front surface of the eye hole 18a by a link mechanism 70 is led into a front channel section 81a and is hooked inside 72a the opening section.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a threading device for threading thread through the eye of a sewing needle of a sewing machine.

[Prior art] Conventionally, as a threading device for a sewing machine, the
As disclosed in Japanese Patent Publication No. 188 and Japanese Patent Application Laid-open No. 63-89194, a threading hook that can penetrate into and escape from the eye of the sewing needle is provided on a support that is movable with respect to the sewing needle, and After hanging the thread inside the opening of the hook,
A device has been developed that threads the thread into the eye hole by letting the hook escape from the eye hole.

Further, there is a device that is provided with an elastic body that reliably holds the thread passed through the eye hole on the hook and pulls it out from the eye hole. This is because as the hook penetrates the eye hole, the elastic body comes into contact with the sewing needle, thereby separating the elastic body from the tip, and when the hook escapes from the eye hole after the thread is hooked, This is a technique in which the elastic body returns to the tip of the hook and holds the thread at the tip of the hook (see Japanese Utility Model Publication No. 35188/1988).

[Problems to be Solved by the Invention] However, in conventional threading devices, the strength of the elastic body provided at the tip of the hook is limited in order to draw out the thread hooked inside the opening of the hook. If the hook is made large, there is a problem in that when the hook penetrates into the eye hole, the elastic body presses the sewing needle strongly and the sewing needle may be bent.

Therefore, conventionally, it has not been possible to simultaneously draw out a large amount of thread from the eye of the sewing needle and prevent the sewing needle from bending.

An object of the present invention is to solve the above-mentioned problems and to draw out a large amount of thread from the eye hole without bending the sewing needle.

[Means for Solving the Problems] As a means for achieving the above object, the threading device of the present invention is provided on a support that is movable with respect to the sewing needle and is capable of penetrating into and exiting from the eye of the sewing needle. In a threading device that is provided with a threading hook, the thread is passed through the eye hole, the thread is hung inside the opening of the threading hook, and the thread is threaded through the eye hole of the sewing needle. The present invention is characterized in that a blocking member is provided on the support body to prevent the elastic member from coming into contact with the sewing needle.

[Function] In the threading device of the present invention, when the threading hook provided on the support body penetrates into the eye of the sewing needle, the elastic member biased inside the opening of the threading hook is activated. Abutment against the sewing needle is prevented by a blocking member provided on the support.

In this manner, in a state where the elastic member is prevented from coming into contact with the threading hook, the threading hook penetrates into the eye hole and hooks the thread inside the opening.

When the thread escapes from the eye hole after being hooked, the prevention of contact with the sewing needle by the blocking member is released as the thread escapes, and the elastic member is urged toward the inside of the opening.

Thereby, the elastic member holds the thread hooked inside the opening without coming into contact with the sewing needle. Therefore, the sewing needle will not be bent by the elastic member, and the thread will not fall out from inside the opening.

[Example code] Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a perspective view of a threading device of a sewing machine which is an embodiment of the present invention. FIG. 2 is an exploded perspective view showing the main parts. The upper shaft 1 is configured to be rotationally driven by a pointed thin motor (not shown), and a crank pin 4 is provided upright on a counterweight 2 attached to the upper shaft 1. One end of the crank rod 6 is inserted. Further, a needle bar holder 8 is rotatably inserted into the other end of the crank rod 6, and this needle bar holder 8 is fixed to the needle bar 10. The needle bar 10 is attached to a needle bar support frame 12.
A sewing needle 18 is supported at the lower end of the needle bar 10 by a needle holder 14 and a tightening screw 16.
is supported. A thread guide 19 is attached near the needle holder 14 to guide the thread 68 into the eye hole 18a of the sewing needle 18.

Furthermore, a positioning stopper 20 is fixed to the needle bar O by a set screw 22 at a predetermined position above the needle bar holder 8. This positioning stopper 20 is formed with a protruding stopper surface 20a perpendicular to the axial direction of the needle bar 10. .

A threading rod 24 is further disposed on the needle bar support frame 12 in parallel with the needle bar 10 and is supported so as to be rotatable about its axis and slidable in the vertical direction.

A threading mechanism 26, which will be described later, is provided at the lower end of the threading rod 24.

On the other hand, on the upper side of the threading rod 24, as shown in FIG.
An operating pin 30 is inserted and fixed so as to pass through the threading rod 24 in the axial direction. This operating pin 30 is connected to the threading rod 2
When the sewing needle 4 is lowered, it hits the stopper 1120a of the positioning stopper 20, and when it hits, the height of the threading hook 72, which will be described later, and the eyelet 18a of the sewing needle 18 become the same height. As such, the positioning stopper 20 is fixed to the needle bar 10 by a set screw 22.

A hollow operating rod 32 is slidably inserted into the threading rod 24, and a compression spring 34 is interposed between the operating pin 30 and the operating rod 32. Further, as shown in FIG. 2, a guide groove 36 is formed along the outer periphery of the operating rod 32 in an arcuate shape and extends upward.
One end of the operating pin 30 is adapted to engage with this guide groove 36. Further, a contact portion 38 is formed at the upper end of the operating rod 32 and projects in the radial direction of the threading rod 24, and a hook portion 39 is formed on the outer periphery of the operating rod 32.
A spring 40 is stretched between the three hook portions and a hook (not shown) integrally formed on a movable table 48, which will be described later, to urge the operating rod 32 upward.

As shown in FIG. 1, one end of an L-shaped support shaft 41 is rotatably attached to the upper end of the needle bar support frame 12 that slidably supports the threading rod 24 into which the operating rod 32 is inserted. The other end of the four support shafts is rotatably connected to a threading support frame 42 fixed to a sewing machine frame (not shown), and is inserted with a set screw 44 to prevent removal. has been done. A guide rod 46 is fixed to the threading support frame 42 in parallel with the threading rod 24, and a movable base 48 provided separately from the operating rod 32 is slidable on the guide rod 46. is inserted into.

This moving table 48 is formed with a groove 50 along the speech and action direction, and a pin 52 erected on the guide rod 46 is engaged with this groove 50, so that when the moving table 48 slides, a groove 50 is formed. Rotation is prevented. Further, an operating rod 3 is provided at the upper end of the moving table 48.
A protrusion 54 is formed that can come into contact with the abutment part 38 when the protrusion 54 protrudes in the second direction and slides. In this embodiment, the moving table 4
8 is in the uppermost position shown in FIG. It is possible to carry out the process even if the protrusion 54 and the abutment part 38 are in contact with each other.

The movable table 48 is provided with a rack portion 56 in which teeth are formed in the sliding direction. This rack section 56
A pinion gear 58 rotatably supported by the threading support frame 42 is meshed with the pinion gear 58 .

The pinion gear 58 is integrated with a helical gear 60, and a worm gear 64 attached to the rotating shaft of a pulse motor 62 attached to the threading support frame 42 is meshed with the helical gear 60. ing.

These worm gear 64, helical gear 601, pinion gear 5B, and rack portion 56 constitute a transmission mechanism 66.

With the above configuration, when the pulse motor 62 of the transmission mechanism 66 is rotationally driven, the movable base 48 is slid downward, descends a predetermined distance, and the protrusion 54 of the movable base 48 is moved to the operating rod 3.
2, and the operating rod 32 is lowered. This lowering of the operating rod 32 causes the compression spring 34 and the guide groove 36 to
, the threading rod 24 is lowered via the operating pin 30, and as the threading rod 24 is lowered, the threading mechanism 26 is also lowered.

Along with the lowering of the threader 24, the operating pin 30 lowers,
The other end of the operating pin 30 abuts against the stopper surface 20a of the positioning stopper 20. At this time, since the rotation of the upper shaft 1 is stopped, the needle bar 10 is fixed via the crank rod 6 and the needle bar holder 8, and further lowering of the threading bar 24 is restricted. When the movable base 48 is further lowered and the operating rod 32 is lowered while the lowering of the threading rod 24 is restricted, the operating rod 32 is lowered against the urging force of the compression spring 34, and at this time the guiding rod 32 is lowered. The actuating pin 30 moves along the groove 36. That is, as the guide groove 36 descends, the threading rod 24 is rotated via the operating pin 30.

By this rotation of the threading rod 24, the threading mechanism 26 performs a predetermined operation as shown below, and the eye hole 18 of the sewing needle 18 is
Thread the thread 68 through a.

As shown in FIG.
As the thread 68 is rotated in the direction of arrow YA of 4,
The link mechanism 70 that extends to the front of 8a and the threading rod 24
A threading hook 72 is provided which rotates together with the threading hook 72 and swings toward the back side of the eye hole 18a of the sewing needle 18.

The link mechanism 70 rotates together with the threading rod 24.
a link part 70a, a second link part 70b rotatably supported by the threading bar 24, a 1° second link part 70a,
70b. fourth link part 70c,
70d.

Third. The connecting pin 70e that connects the fourth link parts 70c and 70d is rotatably fitted onto the lower end of the threading rod 24, and is supported by the needle bar support frame so as to be slidable in the vertical direction. It is slidably fitted into a sliding groove 73a formed in the link guide 73.

The link mechanism 70 has a third. Fourth link portion 70G.

70d and grips the end of the thread 68 with a predetermined pressure, and a gripping member 74 is formed at the end of the second link part 70b to hook and stop the thread 68 that has passed through the thread guide 19. The hook is formed at a position connecting the stop portion 76 and the first and third link portions, and the hook is provided with a thread holding portion 78 located between the stop portion 76 and the gripping member 74 to hold the thread. These are configured so that when the threading rod 24 is rotated in the direction of arrow YA, the thread 68 is stretched over a predetermined length in front of the eye hole 18a of the sewing needle 18, as shown in FIG. has been done.

On the other hand, the threading hook 72 that is swung in the direction of the eye hole 18a and penetrates therein is provided with plate-shaped hook guard plates 80 and 82 at a predetermined interval on both sides in the horizontal direction. As shown in FIG. 6, these threading hooks 72 and hook guard plates 80, 82 are fixed to a support base 84 formed on the first link portion 70a of the link mechanism 70.

One of the hook guard plates 80 and 82 has grooves 8Qa and 82a in the shape of a "shape" formed from the tip thereof, as shown in FIG. 7, which shows the state seen from the right side in FIG. has been done. This groove 80a.

82a is formed in such a shape that the front groove 81a guides the thread 68 to the inner side 72a of the opening, and the rear groove 81b is formed in a shape along the lower part of the threading hook 72.

As shown in FIG. 6, a coiled portion 86a of an elastic wire 86 is wound around the threading rod 24 that holds the hook guard plates 80, 82, etc. via the support stand 84. The -@86b of this wire 86 is bent at right angles and fixed to the support stand 84, and the central part 86c is bent into a stepped shape, and the ends are connected to the hook guard plate 86 as shown in FIG.
0 and 82 grooves 80a and 82a. This wire 86 is interposed in the grooves 80a and 82H, and
As shown by the two-dot chain line in FIGS. 6 and 7, it is configured to be pressed against the opening inner side 72a of the threading hook 72 with a predetermined biasing force.

As the wire 86 moves toward the back side of the eye hole 18a, the second link portion 70b that moves toward the front side of the eye hole 18a has a base portion thereof, as shown in FIGS. 4 and 6. A plate member 88 is attached to. This plate member 8
8 is a center portion 86c of the wire 86 immediately before the wire 86 comes into contact with the sewing needle 18 when the threading hook 72 and the second link portion 70b face each other and move toward the eye hole 18a.
It is placed in a position where it comes into contact with the That is, when the threading hook 72 penetrates into the eye hole 18a, the wire 86 that is biased inside the opening 72a is pushed into the sewing needle 18.
It is configured to prevent contact with the

After the plate member 88 comes into contact with the wire 86, the threading hook 72
As the second link portion 70b faces each other and moves toward the eye hole 18a, the wire 86 is pushed by the plate member 88, and the wire 86 is separated from the inner side 72a of the opening, and the wire 86 is moved toward the eye hole 18a.
It moves in the direction shown by the solid line in FIGS. 6 and 7 while being guided by the rear groove portions 81b of 0a and 82a.

In this manner, when the threading hook 72 is inserted into the eye hole 18a to a predetermined position while the wire 86 is prevented from coming into contact with the sewing needle 18, the link mechanism 70 opens the eye hole 18a as shown in FIG. The thread 68 stretched on the front surface of the hole 18a is guided to the front groove 81a and is hooked to the inside of the opening 72a.

In the state shown in FIG. 8, when the pulse motor 62 is reversed and the threading rod 24 is rotated in the direction of arrow YB shown in FIG. 5, the threading hook 72 and the second link part 70b are separated. Move in the direction you want.

As a result, the threading hook 72 hooks the thread 68 and escapes from the eye hole 18a, as shown in FIG. It is again urged toward the inside of the opening 72a. When the threading rod 24 further rotates in the YB direction from this state and returns to the state before rotating in the arrow YA direction, that is, the initial state, as shown in FIGS. The hook 72 moves backward while holding the thread 6B. Therefore, the thread 68 is pulled out long from the eye hole 18a.

The threading device of the sewing machine explained above uses a pulse motor 6.
The threading mechanism 26 is provided with a threading mechanism 26 that operates with a driving force of 2, and this threading mechanism 26 passes the thread 68 through the eyelet 1 by means of a link mechanism 70.
The stretched thread 68 is hung on the threading hook 72, passed through the eye hole 18a, and then pulled out for a long time.

This allows threading the thread 68 through the eye hole 18a by driving the pulse motor 62.
It becomes possible to electronically control the threading process. Moreover, since the wire 86 is provided to hold the thread 68 inside the opening 72a without coming into contact with the sewing needle 18,
Insert the wire 86 into the opening 72 without bending the sewing needle 18.
It is possible to increase the force that urges a, and it becomes possible to increase the force that holds the thread 68. Therefore, the thread 68 can be drawn out for a long time from the eye hole 18a. As a result, eye hole 1
The thread 68 passed through the thread 8a does not fall out and the threading fails, and this threading device prevents the
The thread 68 threaded through the thread 8a can be moved directly to the sewing work without having to be further pulled out by hand. In other words, it is possible to simultaneously improve the reliability of the sewing machine and the efficiency of sewing work.

Note that the present invention is not limited to the examples, and can be implemented in various forms without changing the gist of the present invention.

[Effects of the Invention] The threading device of the present invention, after the threading hook penetrates into the eye hole, removes the thread hooked inside the opening from the eye hole.
It is held inside the opening by an elastic member. therefore,
Even after the threading hook escapes from the eye hole, the thread is pulled out without coming off from inside the opening, and the thread can be pulled out for a long time from the eye hole.

This eliminates the possibility of failure in threading due to insufficient threading amount into the eye hole, and provides an extremely excellent effect of improving the reliability of threading. Furthermore, since the amount of thread passing through the eye hole becomes longer, it is possible to start sewing without pulling out the thread further after threading.
Work efficiency improves.

Further, since the elastic member holding the thread inside the opening is prevented from coming into contact with the sewing needle, the sewing needle can be prevented from being damaged during threading. Therefore, it is possible to improve the reliability of the sewing machine while improving the reliability of the threading operation.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a part of a threading device of a sewing machine as an embodiment of the present invention, Fig. 2 is an exploded view of the main parts of this embodiment, and Fig. 3 is a positioning stopper of this embodiment. 4 to 6 are plan views of the main parts of this embodiment, FIG. 7 is a side view of the hook guard plate of this embodiment, and FIGS. 8 to 11 are views of this embodiment. It is an explanatory diagram of the operation. ]...Upper shaft 10...Needle bar 18...
・Sewing needle 18a...Eye hole 24...Threading guard 26...Threading mechanism 62...Pulse motor 70...Link mechanism 72...Threading hook 80.82...Hook guard Plate 80a, 82a...Groove 86...Wire 88...Plate member

Claims (1)

[Scope of Claims] 1. A threading hook that can penetrate into and escape from the eye of the sewing needle is provided on a support that is movable with respect to the sewing needle, and an opening of the threading hook that passes through the eye. A threading device for hooking a thread on the inner side of the hook and threading the thread through the eye hole of the sewing needle, comprising an elastic member biased inside the opening of the threading hook, the elastic member abutting the sewing needle. A threading device characterized in that a blocking member is provided on the support to prevent the support from coming into contact with the support.