JP3103735B2 - Bobbin case of bobbin winding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for winding a bobbin thread on a bobbin.

[0002]

2. Description of the Related Art In a conventional lockstitch sewing machine, when a bobbin wound around a bobbin runs out, the bobbin is removed together with the bobbin case from the shuttle, the bobbin is wound around the bobbin, and the bobbin is attached to the shuttle again. Or replacing the bobbin with a bobbin wound with a bobbin prepared in advance.

[0003]

However, the operation of manually winding the bobbin thread on the bobbin and the operation of replacing the bobbin case require a lot of time and labor, and therefore, Japanese Patent Application No. Hei. -188688 and Japanese Patent Application No. Hei 6
JP-A-64456 discloses a device that automatically winds a bobbin, and also automatically hooks a bobbin case and cuts a bobbin thread into a bobbin case that has been threaded. I have.

As shown in FIGS. 24 and 25 , a bobbin case including a device described in the above-mentioned Japanese Patent Application Nos. 4-188688 and 6-64456 has a bobbin case. The bobbin 7 incorporated in the
Is automatically wound, and the lower thread 150 wound around the bobbin 7 and led out from the opening 8A of the bobbin case 8 is
The lower thread 150 led out from the lower thread outlet hole 8GG is guided to the lower thread outlet hole 8GG through the gap 8K between the open end edge 8EE of the bobbin case 8 and the outer periphery of the bobbin and the slit groove 8CC at the thread hooking position 8B. The bobbin case 8 is drawn out from the lower thread tension spring hole 8H below the bent end 8DD which is bent inward (in the axial direction of the bobbin) of the end of the thread tension spring 8D.
Threading is automatically performed.

Here, in the conventional bobbin case 8, the inclination angle θ of the slit groove 8CC with respect to the bobbin case open end portion 8EE through which the bobbin thread 150 passes at the time of threading.
Is approximately 60 ° , which is relatively gentle with respect to the bobbin axis direction .
The lower thread 150 guided to the slit groove 8CC by the lower thread guiding mechanism such as
For guiding to G, a lower thread guiding auxiliary mechanism such as a wiper mechanism (moving mechanism in the bobbin axis direction; see Japanese Patent Application No. 6-64456) is required.

[0006] In addition to the above function, this bobbin thread guiding auxiliary mechanism has a bobbin thread 1 inserted into the opening 8A of the bobbin case 8 when the bobbin thread is wound.
The bobbin case 8 must also have a function of moving the bobbin thread 150, that is, it must be able to guide the bobbin thread 150 in different directions.
In the case of a structure that emphasizes the function of shifting the lower thread, the lower thread guiding auxiliary mechanism may not be able to satisfactorily guide the lower thread 150 from the slit groove 8CC to the lower thread outlet hole 8GG.

The positional relationship between the lower thread lead-out hole 8GG and the lower thread tension spring hole 8H in the bobbin axis direction is such that the lower thread lead-out hole 8GG is closer to the open end of the bobbin case 8 than the lower thread tension spring hole 8H. 24 (right side in FIG. 24), even if the lower thread 150 is in the lower thread outlet hole 8G.
24, the lower thread 150 guided to the lower thread lead-out hole 8GG is guided to the lower thread tension spring hole 8H.
In order to guide to the left side in and draw out from the lower thread tension spring hole 8H, a lower thread guiding auxiliary mechanism such as the wiper mechanism is required.
For example, in a case where a structure that emphasizes the function of moving the lower thread 150 to the opening 8A of the bobbin case 8 is used, the lower thread lead-out hole 8G
There is a fear that the lower thread 150 may not be guided to the lower thread tension spring hole 8H from G.

Also, as described above, the lower thread 15
0 passes through the gap 8K between the open edge 8EE of the bobbin case 8 and the outer periphery of the bobbin, so that the lower thread 150 comes into contact with the open edge portion 8EE of the bobbin case. Since the lower thread 150 is originally a part that does not touch, it often has sharpness, burrs, scratches, and the like. Therefore, the thread breaks while the lower thread 150 passes through the gap 8K, and the reliability of the device is reduced. There is a problem that the performance is reduced. In particular, in the above-described device, since the looseness of the lower thread 150 is removed and the lower thread 150 is tightened at the time of threading, the lower thread 150 is strongly pressed against the bobbin case open edge portion 8EE. And thread breakage is likely to occur. Similarly, when the yarn count is increased and reduced, the yarn is likely to break.

Accordingly, a first object of the present invention is to provide a bobbin case of a lower thread winding device which can successfully complete a thread hooking operation without using a lower thread guiding auxiliary mechanism.

[0010] In addition to the first object, the present invention provides a bobbin case of a lower thread winding device capable of preventing thread breakage during threading and improving reliability. This is the purpose of 2.

[0011]

In order to achieve the first object, a bobbin case of a lower thread winding device according to claim 1 is
A bobbin thread is automatically wound around a bobbin incorporated in a bobbin case, and a bobbin thread wound around the bobbin and led out from an opening of the bobbin case is removed from a gap between an open end edge of the bobbin case and an outer periphery of the bobbin. By guiding the lower thread to the lower thread guide hole through the slit groove and leading the lower thread from the lower thread guide hole from the lower thread tension spring hole below the lower thread tension spring end,
A bobbin case applied to a bobbin winding device configured to automatically thread a bobbin case, wherein an inclination angle of a slit groove with respect to a bobbin case open edge portion through which the bobbin thread passes at the time of threading. Is set to 30 ° to 45 °, the slit groove is steeply inclined with respect to the bobbin axis direction, and the positional relationship between the lower thread lead-out hole and the lower thread tension spring hole in the bobbin axis direction is determined by the lower thread. The lead-out hole is set so as to be located on the opposite side of the bobbin case from the opening for the lower thread tension spring.

In order to achieve the second object, the bobbin case of the bobbin winding device according to claim 2 is, in addition to the above-described claim 1, provided with a bobbin case opening edge portion through which the bobbin thread passes at the time of threading. The bobbin is characterized in that chamfering is performed so that the cross section in the axial direction becomes curved.

[0013]

According to the bobbin case of the bobbin winding device according to the first aspect, the inclination angle of the slit groove with respect to the open end portion of the bobbin case through which the bobbin thread passes at the time of threading is made steep. Therefore, movement of the lower thread from the thread hooking position to the lower thread lead-out hole can be easily performed without a lower thread guiding auxiliary mechanism such as a wiper mechanism, and the lower thread lead-out hole is connected to the lower thread tension spring. Since the bobbin thread is located on the side opposite to the open end of the bobbin case in the bobbin axial direction from the use hole, the bobbin thread guided to the bobbin thread lead-out hole can be used without a bobbin thread guiding auxiliary mechanism such as a wiper mechanism. It is easily guided to the hole for the bobbin thread tension spring.

According to the bobbin case of the bobbin winding device according to the second aspect, even if the bobbin thread abuts on the open end portion of the bobbin case at the time of threading, a curved chamfering process is performed on the abutting portion. As a result, yarn breakage during yarn hooking is prevented.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, with reference to FIGS. 19 to 23, an outline of a bobbin thread automatic feeder employing a bobbin winding to which the bobbin case of the present invention is applied will be described.

This bobbin thread automatic supply device is provided with a sewing machine bed 1
Is located in the space where the bottom below is an oil sump,
As shown in FIGS. 19 and 20, the bobbin case attaching / detaching position A, the residual yarn removing position B, and the bobbin winding position C are arranged at 120 ° intervals around one axis, and as shown in FIGS. , Bobbin case attaching / detaching position A and other working positions B and C
Is divided into both ends of the one axis, and a column 2 erected in the space, a main base 3 mounted on the column 2, and the single axis horizontally supported by the main base 3. A guide shaft 4 and a rotary arm 5 rotatably supported with the guide shaft 4 and slidable in the axial direction.
A forward / backward lever 6 for moving the rotating arm 5 forward and backward along the guide shaft 4;
And a driving device for rotating the motor forward or backward.

As shown in FIG. 22, the guide shaft 4 is rotatably supported at both ends by an upright portion of the main base 3. As shown in FIG. 23, the cross section is non-circular, and the shape of the corresponding hole of the boss 5a of the rotating arm 5 is the same. Therefore, the rotating arm 5 can slide along the guide shaft 4 and can rotate together with the guide shaft 4.

As shown in FIG. 19, the pivot arm 5 extends slightly symmetrically from the center to both sides, and has a bobbin 7 built in near each end as shown in FIG. A bobbin case 8 is detachably supported. The bobbin attaching / detaching mechanism in the rotating arm 5 is described in, for example,
For example, the present invention relates to a pair of electromagnet suction heads described in Japanese Laid-Open Patent Application No. 92476, a bobbin thread automatic feeding device and a bobbin changing device of a sewing machine disclosed in Japanese Patent Application No. 5-121960 filed by the present applicant. Japanese Patent Application No. Hei 5 filed earlier
A suitable device such as a device using a lever claw described in a bobbin changing device of a sewing machine described in Japanese Patent No. 116363 can be used. What is necessary is just that it can be attached to and detached from.

The forward / reverse lever 6 is rotatably supported by a shaft 9 erected on the main base 3 as shown in FIGS. A long hole 6a is formed near the free end. The other end is rotatably attached to a shaft 13 fixed to a knuckle 12 at the rod end of an air cylinder 11 attached to the main base 3 by a support plate 10. As shown in FIG. 22 and FIG.
Of the collar 14 rotatably attached to the boss 5a of the
A pin 15 projecting from the surface is engaged. Therefore, when the rod of the air cylinder 11 expands and contracts, the forward / reverse lever 6 rotates forward and backward around the shaft 9. Accordingly, the rotating arm 5 moves forward and backward along the guide shaft 4 via the pin 15 which engages with the long hole 6a of the forward and backward moving lever 6.
That is, the rotating arm 5 is connected to the shuttle 1 shown in FIGS.
It is possible to move forward and backward along the guide shaft 4 along the bobbin case attaching / detaching position A side and the opposite side (the remaining yarn removing position B and the bobbin winding position C exist), which are the sewing positions provided at 6. it can.

The rotation driving device of the rotating arm 5 is shown in FIG.
As shown in FIG. 21, a motor 19 attached to a bracket 18 fixed to a bracket 17 below the main base 3 and a gear 21 fixed to a rotation shaft 20 thereof
A gear 22 that is rotatably supported by the bracket 17 and meshes with the gear 21, a master wheel 23 fixed to one surface of the gear 22, a pin 24, and a driven wheel 25 that is rotatably supported by the bracket 17. The mechanism, a gear 26 coaxially fixed to the driven wheel 25, and a guide shaft 4 (FIG. 2)
2) a gear 27 meshing with the gear 26. Therefore, by configuring the gear 26 and the gear 27 at a predetermined gear ratio, the rotating arm 5 is rotated by the Geneva mechanism of the rotation driving device in units of 60 ° via the guide shaft 4 using the motor 19 as a driving source. .

At the residual yarn removing position B, for example, Japanese Patent Application No. 5-203610 or Japanese Patent Application No.
The bobbin residual yarn removing device disclosed in Japanese Patent No. -40351 can be used, and any suitable device can be adopted.
A bobbin thread that has a pinching member capable of pinching or releasing the end of the thread wound around the bobbin, and that can be automatically wound around the bobbin thread pinched by the pinching member by rotating about a single axis. Anything may be used.

In the automatic bobbin thread supplying device configured as described above, the rotation of the motor 19 causes the rotating arm 5 to repeat forward / reverse rotation in units of 60 ° and forward / backward movement along the guide shaft 4 to repeat. The bobbin case 8 is reliably transported to each of the work positions A, B, and C to execute or receive work.

For example, without holding the bobbin case 8 at one end of the rotating arm 5, holding the bobbin case 8 with a built-in bobbin (described later in detail) 7 by a bobbin winding device at the other end. Further, it is assumed that one end not holding the bobbin case 8 is waiting at a position D (see FIG. 20) between A and B. When predetermined sewing is completed in this state, the rotating arm 5 rotates counterclockwise in FIG. 20 by 60 ° and advances to the shuttle side in FIG.
The bobbin case 8 with a built-in bobbin with the remaining yarn is held at one end of the rotating arm 5 from the shuttle 16 at the end.

Next, when the rotating arm 5 retreats to the retracted position of the guide shaft 4 and rotates by 180 ° and moves forward, the bobbin case 8 having a bobbin wound on the bobbin held at the other end of the rotating arm 5 is wound. It is attached to the shuttle 16 at the bobbin case attaching / detaching position A. Then, when the rotating arm 5 moves backward and rotates 60 ° in the counterclockwise direction in FIG. 20, the bobbin case 8 with a built-in bobbin with a remaining thread held at one end of the rotating arm 5 advances to the remaining thread removing position B. The remaining yarn removing device there removes the remaining yarn of the bobbin 7, and the bobbin becomes an empty bobbin without a yarn. Thereafter, when the rotating arm 5 rotates clockwise in FIG. 20 by 120 ° and retreats, the bobbin case 8 with the empty bobbin from which the remaining yarn has been removed advances to the lower thread winding position C, and is operated by the lower thread winding device there. A bobbin thread is wound around an empty bobbin. Thereafter, these operations are repeated.

Next, the lower thread winding device disposed at the lower thread winding position C will be described below with reference to FIGS. 1 to 7 and FIG.

In this bobbin winding device, the bobbin thread is clamped to introduce the bobbin thread into the bobbin case, and by applying rotation to the bobbin and releasing the clamp, the bobbin thread is wound into the bobbin case while being housed. The operation of winding the bobbin on the bobbin, the operation of hooking the bobbin wound on the bobbin and leading out from the opening of the bobbin case to the bobbin case, and the operation of winding the bobbin from the bobbin wound on the bobbin case, An operation of cutting the bobbin case leaving a certain length from the lower thread tension spring to form an intertwined seam with the thread, so that these operations can be repeated,
All operations such as re-clamping the bobbin thread from the bobbin can be automatically performed, and the bobbin thread tension during these series of operations can be optimally set.

As shown in FIG. 1, the lower thread winding device includes a sub-frame 10 mounted on the main base 3.
One. The sub-frame 101 has a substantially U-shape, and is arranged such that the opening faces downward. Through holes are formed coaxially on both side plates of the subframe 101, and bearings 103 and 104 are respectively mounted in these through holes as shown in FIG.

As shown in FIG. 3, one of the bearings 104 is provided so as to protrude from one surface of the pulley 106 and has a slit 1.
A boss 106c having a shape obtained by symmetrically dividing the cylindrical portion into two parts in the axial direction by 06b is rotatably supported. Pulley 1
A boss 106a having a substantially cylindrical shape is provided on the other surface of
The shaft hole of the pulley 106 and the boss 106c are formed coaxially. As shown in FIG. 2, a winding shaft 107 is inserted into the shaft holes of the boss 106a, the pulley 106, and the boss 106c, and the winding shaft 107 is supported by the pulley 106. I have. A pin hole orthogonal to the axial direction is formed at an end of the winding shaft 107 corresponding to the bearing 104. This pin hole has a pin 1
Reference numeral 08 is fitted and fixed, and both ends of the pin 108 are loosely fitted in the slit 106b.
Therefore, the rotation of the pulley 106 is controlled by the boss 106c and the pin 10
8, the winding shaft 107 can slide in the axial direction at the same time because both ends of the pin 108 can slide in the slit 106b.

On the other bearing 103, a thread clamp shaft 105 as a thread clamp means having a substantially cylindrical shape and having a flange at the left end in FIG. 2 is slidably supported in the axial direction. A part of the winding shaft 107 is inserted into a shaft hole of the yarn clamp shaft 105 on the side opposite to the pulley, and the winding shaft 1
07 is supported by the thread clamp shaft 105 so as to be slidable in the axial direction. The boss 106a is inserted into a shaft hole on the pulley side of the thread clamp shaft 105, and the thread clamp shaft 105 is slidable on the boss 106a.

A flange is formed at the end of the winding shaft 107 on the side opposite to the pulley. On the surface of this flange portion, a pin 107 a for clutching an existing hole provided in the flange of the bobbin 7 and transmitting the rotation of the winding shaft 107 to the bobbin 7.
Are formed on the peripheral surface, and a large number of convex surfaces are formed at equal intervals on the peripheral surface to prevent the lower thread from slipping on the peripheral surface.

At substantially the center of the winding shaft 107 in the axial direction, E
The ring 109 is mounted so as to protrude outward, and compression springs 110 and 111 are provided between the inner wall surface of the clamp shaft 105 and the E ring 109 and between the E ring 109 and the inner wall surface of the pulley 106. Each is arranged. Accordingly, the take-up shaft 107 is urged leftward in FIG. 2 with respect to the pulley 106 by the compression spring 111, and the thread clamp shaft 105 is taken up by the compression spring 110
07 is urged to the left in FIG. That is, the yarn clamp shaft 105 and the winding shaft 107 are always
And the winding shaft 107
The flange of the thread clamp shaft 105 is in pressure contact with the flange of.

As shown in FIGS. 2 and 4, the rotary drive mechanism of the pulley 106 includes a motor 115, a transmission shaft 114 mounted on the output shaft of the motor 115 along the same axis, and a transmission shaft 114. Pulley 1 fixed to 114
13 and a timing belt 112 stretched over the pulley 113 and the pulley 106. Therefore, the rotational driving force of the motor 115 is
4, and transmitted to the pulley 106 via the pulley 113 and the timing belt 112.

As shown in FIG. 1, a flange 105a is formed at an end of the thread clamp shaft 105 on the pulley side, and a roller 136a is applied to an end surface of the flange 105a on the side opposite to the pulley. It is in contact (initial state).
The roller 136a is supported by a lever 136, as shown in FIG.
37 is fixed to one end. The collar 137 is rotatably supported by the support column 2, and one end of a link 138 is fixed to the other end of the collar 137 rotated in the counterclockwise direction by 90 °. One end of a link 139 is pivotally connected to the other end of the link 138, and the other end of the link 139 is pivotally connected to a piston rod of the air cylinder 140. Therefore, the air cylinder 140 is driven (in this embodiment, the piston rod is retracted).
The collar 137 rotates clockwise in FIG. 2, and the roller 136 a causes the flange 1 of the thread clamp shaft 105 to resist the urging force of the spring 110 urging the thread clamp shaft 105.
05a to the pulley side, and as a result, the yarn clamp shaft 10
5 retreats to the pulley side, so that a gap is formed between the flange of the thread clamp shaft 105 and the flange of the winding shaft 107.

As shown in FIG. 2, a substantially cylindrical collar 180 is fitted around the outer periphery of the bearing 103, and the collar 180 is prevented from coming off in the axial direction by a C-ring 90. A thread handling mount with moving knife 116a protrudes from the upper portion of the collar 180 in FIG. 2, and the thread handling 116 with moving knife shown in FIG. 5 is fixed to the thread handling mount with moving knife 116a. Have been.

The threading with a moving knife 116 has V-shaped cutouts 116C and 116D for guiding a lower thread at its front end (front side in FIG. 2) and rear end (back side in FIG. 2). Having a moving knife plate 116A,
As shown in FIG. 5 and FIG. 13, the notches 116 </ b> C and 116 </ b> D have a vertex of the notch 116 </ b> C.
It is formed to be shifted to the left in FIG. 2 with respect to the vertex of 16D. Notch 116C on the upper surface of moving knife plate 116A
An eyeball (moving knife) 116E for cutting is formed on a line roughly connecting the vertex of the notch and the vertex of the cut portion 116D, and a small gap through which the fixed knife 91 shown in FIG. A thread dividing feather 116B that is empty and has a slightly shifted edge is provided. As shown in FIG. 4, the moving knife plate 116A and the thread dividing wing 116B are both curved in an arc shape with the winding shaft 107 as the center. When the position of the fixed knife 91 is reached, the moving knife 116E on the back of the moving knife plate 116A rubs against the tip of the fixed knife 91,
Each positional relationship is adjusted.

A gear 122 is formed on the outer periphery of the collar 180 as shown in FIG.
22 is a gear 121, a gear 120, a gear 119, a gear 1
18. Motor 1 that can rotate forward and reverse through gear 117
23 is driven to rotate. In other words, by driving the motor 123, the collar 180 and the thread handling with moving knife 116 are rotated in forward and reverse directions.

As shown in FIGS. 1, 6, and 7, on the upper outer periphery of the bearing 103, a thread hooking lever 124 is rotatably supported by a stepped screw 124a on a plane perpendicular to the plane of FIG. Have been. This thread hook lever 12
4, a hook 124 is provided at the distal end as shown in FIG.
A and an inclined surface 124B connected to the hook 124A and inclined from upper to lower right in FIG. 6 are formed. The thread hook lever 124 is connected to the torsion spring 12.
5, it is urged in the counterclockwise direction in FIG.
Normally, it is in the state shown by the solid line in FIG.

A wiper 130 is provided on the front side of the winding shaft 107 in FIG. The wiper 130 has a rod shape with a partly bent part,
(See FIGS. 20 and 21) A shaft 129 that can rotate coaxially with the shaft 129.
Is fixed to its central part. A gear 132 is fixed to an end of the shaft 129. The gear 132 has a gear 133 having an axis in a direction orthogonal to the axis of the gear 132.
Are engaged. The end of the gear 133 has a link 1
One end of 31a is connected. The other end of the link 131a has a link 131 as shown in FIGS.
The other end of the link 131b is pivotally connected to one end of a link 131c. The other end of the link 131c is a rotary air cylinder 1
34. Accordingly, when the air cylinder 134 is driven, the wiper 130 rotates around the shaft 129.

Above the above-mentioned moving-knife-equipped thread handling 116,
11 and 13, a thread guide 92 for guiding the lower thread 150 supplied from the thread winding 200 (see FIG. 18) is fixedly arranged. The thread guide 92 is formed in a flat plate shape and stands substantially horizontally, and a long hole 92a through which a bobbin thread passes is formed in the plate portion. The elongated hole 92a has a height difference that is inclined from left to right in FIG. 10, so that the lower thread that moves in the axial direction during operation is guided along the elongated hole 92a. I have.

As shown in FIG. 18, a mechanism is provided between the yarn guide 92 and the bobbin 200 to remove the looseness of the lower thread. This mechanism attaches a lever 201 having a lower thread 150 passed through through holes at both ends, a shaft 203 rotatably supporting the lever 201, and one end (upper end in the figure) of the lever 201 in the right direction in the figure. And a biasing spring 202.
The looseness of the downstream lower thread 150 is removed.

Between the lever 201 and the bobbin 200,
A thread tension varying means 204 for varying the tension of the lower thread 150 is provided. The thread tension varying means 204 includes a tension spring 205 for pressing the lower thread 150 passing therethrough, a screw 206 for adjusting the pressing force of the tension spring 205 by manual operation, and a tension spring 20 disposed in the sewing machine bed 1.
And a solenoid SOL that generates a solenoid thrust against the pressing force of No. 5.

The electric circuit for driving the yarn tension varying means 204 has a configuration in which a power supply V is connected in series to a solenoid SOL, and a switch SW is interposed therebetween.

Therefore, when the switch SW is turned off, the solenoid thrust is not generated, the pressing force of the tension spring 205 is applied to the bobbin thread 150 to the maximum, and the bobbin thread tension is maximized. When the switch SW is turned on, the above-described solenoid thrust is generated to the maximum, and the lower thread 150 is applied with a force obtained by subtracting the solenoid thrust from the pressing force of the tension spring 205, and the lower thread tension is minimized.

The bobbin case 8 which is a feature of the present invention shown in FIGS. 8 and 9 is applied to the bobbin winding device (of course, also to the bobbin automatic supply device). In the bobbin case 8, the inclination angle θ1 of the slit groove 8C with respect to the bobbin case open end portion 8E through which the bobbin thread 150 passes at the time of threading is set to 30 ° to 45 °.
The and bobbin case 8 is formed, the slit groove 8C as compared with the conventional bobbin case shown in FIG. 24, FIG. 25
It is the slope and has a steep slope.

In the bobbin case 8, the lower thread lead-out hole 8G is located on the side opposite to the open end of the bobbin case 8 in the bobbin axial direction (vertical direction in FIG. 9) from the lower thread tension spring hole 8H (FIG. 9). On the upper side of
The bobbin case 8 is formed.

Further, in the bobbin case 8, as shown in FIG. 8 (b), the bobbin case open end portion 8E through which the lower thread 150 passes during threading has a curved cross section in the bobbin axial direction. Chamfering is performed.
This chamfering is performed by, for example, buffing or machining, and the surface of the chamfered portion 8e is smooth. The chamfered portion 8e may be coated with, for example, Teflon.

Next, the operation of the lower thread winding device thus configured will be described below with reference to FIGS.

First, the rotary arm 5 of the above-described automatic bobbin thread supply device rotates, and the bobbin case 8 with the empty bobbin 7 from which the remaining thread has been removed reaches the bobbin thread winding position C.

At this time, the bobbin winding device is in an initial state as shown in FIG.
Numeral 0 is passed through a long hole 92a of the yarn guide 92, and the tip is clamped between the flange of the yarn clamp shaft 107 and the flange of the winding shaft 105 by manual operation. The clamping after the second winding is automatically performed at the end of the first winding operation (details will be described later).

At this time, the switch SW of the thread tension varying means 204 is turned on to generate the above-mentioned solenoid thrust to the maximum and to minimize the lower thread tension.

Next, the rotating arm 5 is moved forward (to the right in the drawing), and the pin 107a of the winding shaft 107 is clutched to an existing hole provided in the flange of the bobbin 7. Then, as shown in FIG. 11, the wiper 130 is moved about 18
Rotated by 0 °. Then, the thread portion between the clutched tip portion of the lower thread 150 and the thread guide 92 is hooked on the wiper 130, and the opening 8A of the bobbin case 8 is opened.
Sent to

Next, the motor 115 is driven to rotate the winding shaft 107, and the bobbin thread 150 is wound around the bobbin 7. Then, wiper 1 is
The lower thread 30 is returned to the initial position, and the motor 115 is further driven to wind a small amount of the lower thread 150 around the bobbin 7.

When the bobbin 7 is wound in a small amount on the bobbin 7, the thread clamp shaft 105 is retracted by the air cylinder 140 (moved to the right in the drawing), and the motor 115 is further driven. Then, thread clamp shaft 1
The yarn end at the beginning of the winding, which is clamped between the flange portion 07 and the flange portion of the winding shaft 105, is automatically stored in the bobbin case 8 (see FIG. 12). Then, the driving of the motor 115 is continued, the bobbin thread 150 is wound around the bobbin 7 by a set amount, and the motor 115 is stopped.

After the bobbin 7 is wound around the bobbin 7 automatically, the bobbin case 8 is hooked.

First, the switch S of the yarn tension varying means 204
W is turned off to eliminate the above-mentioned solenoid thrust and maximize the bobbin thread tension.

Then, the motor 123 is driven to rotate the thread separating 116 with a moving knife a half turn. Then, as shown in FIG. 13, the lower thread 150 led out from the opening 8A of the bobbin case 8 is caught by the apex of the V-shaped cutout 116D, and the lower thread 150 on the lower thread tension spring side of the bobbin case 8 is formed. It moves toward the threading position 8B.

At this time, the lower thread 150 goes to the thread hooking position 8B while passing through the gap 8K (see FIG. 8) between the open edge 8E of the bobbin case 8 and the outer periphery of the bobbin, but the lower thread tension may be maximized. The bobbin thread 150 is pressed against the bobbin case open end portion 8E. As described above, the contact portion 8E is chamfered so that the cross section in the bobbin axial direction is curved. The thread breakage by the portion 8E does not occur.

The bobbin thread moving toward the threading position 8B abuts against the inclined surface 124B of the threading lever 124 and pushes the threading lever 124 in the traveling direction. 13 is urged by the torsion spring 125 in the direction opposite to the traveling direction.
As shown in (2), the lower thread is guided to the slit 8C at the threading position 8B after pushing the threading lever 124 in the advancing direction by a predetermined amount. Thereafter, the motor 123 is driven to rotate the moving knife-equipped thread handling 116 in the reverse half, and the moving knife-equipped thread handling 116 is returned to the original position (see FIG. 14).

At this time, the bobbin thread tension is at a maximum and the inclination of the slit groove 8C is steep.
The lower thread 150 guided to the slit groove 8C is guided to the lower thread outlet hole 8G below the lower thread tension spring 8D. This lower thread outlet hole 8
The lower thread 150 guided to G has a lower thread lead-out hole 8G in the bobbin case in the bobbin axis direction than the lower thread tension spring hole 8H.
Since it is located on the side opposite to the open end edge of No. 8 , it is directly guided to the lower thread tension spring hole 8H (see FIG. 15).

After the thread hooking operation on the bobbin case 8 is automatically performed in this way, then, the bobbin thread supplied to the bobbin case 8 on which the thread is hooked is cut off.

First, the switch S of the yarn tension varying means 204
W is turned on to generate the above-mentioned solenoid thrust to the maximum and minimize the bobbin thread tension.

Next, the motor 123 is driven to rotate the threading with a moving knife 116 in the direction opposite to that in FIG.
Then, as shown in FIG. 16, the lower thread 150 derived from the lower thread tension spring 8D of the bobbin case 8 is caught at the apex of the V-shaped cut portion 116C, and the thread is pulled out.

The pulled out yarn is caught at the apex of the V-shaped cut portion 116C, and the yarn separating wings 116C
By B, it is sorted to the right side in FIG. Accordingly, the lower thread from the thread guide 92 is, as shown in FIG.
The bobbin thread guided to the right side in the drawing is guided by 2a,
07.

At this point, the retracting of the thread clamp shaft 105 by the air cylinder 140 is released. Then, the thread clamp shaft 105 advances to the left in the figure by the urging force of the spring 110 shown in FIG. 2, and the thread guide 92 is moved between the flange of the thread clamp shaft 105 and the flange of the winding shaft 107. The lower thread from is clamped.

Then, the motor 123 is further driven to slightly rotate the thread separating 116 with a moving knife in the same direction. Then, the moving knife 116E of the moving knife 116 with a moving knife and the fixed knife 91 face each other, and the lower thread 150 therebetween is cut.
That is, the lower thread derived from the lower thread tension spring 8D of the bobbin case 8 has a predetermined length and is cut. This fixed length is a length necessary for forming a stitch by entanglement with the upper thread, and the position of the fixed knife 91 and the like is adjusted so as to secure the length.

When the bobbin thread cutting operation is automatically performed, the rotating arm 5 retreats to the retracted position of the guide shaft 4 and rotates, moves forward, and is held by the rotating arm 5 and the bobbin thread has been wound. The bobbin case 8 with a built-in bobbin is mounted on the shuttle 16 at the bobbin case attaching / detaching position A.

At this time, in the bobbin winding device, the lower end of the bobbin 200 from the bobbin 200 is held between the flange of the thread clamp shaft 107 and the flange of the winding shaft 105 as described above. To return to the standby state.

In the above description, the lower thread 150 is guided to the lower thread tension spring hole 8H by the inclination angle θ1 of the slit groove 8C, but the lower thread is turned by the rotation of the thread handling 116 accompanying the cutting operation of the lower thread 150. The movement of the thread 150 to the lower thread tension spring hole 8H becomes more reliable. That is, as shown in FIG. 16, the lower thread is captured by the V-shaped cut portion 116 </ b> C of the thread handler 116 with the moving knife while the thread handler 116 having the moving knife is rotated in the reverse direction, and the lower thread 150 is removed from the slit groove 8 </ b> C. It is guided to the lower thread tension spring hole 8H through the lower thread lead-out hole 8G.

As described above, in the present embodiment, the bobbin case open edge portion 8 through which the lower thread 150 passes when the thread is hooked.
The inclination angle θ1 of the slit groove 8C with respect to E is 30 ° to 4 °.
5 °, the slit groove 8C is steeply inclined with respect to the bobbin axis direction, and the movement of the lower thread from the thread hooking position B to the lower thread lead-out hole 8G can be performed without a lower thread guiding auxiliary mechanism such as a wiper mechanism. And the lower thread outlet hole 8
G and position in the bobbin axial direction of the lower thread tension spring hole 8H
The arrangement is set such that the lower thread lead-out hole 8G is located on the side opposite to the open end edge of the bobbin case 8 from the lower thread tension spring hole 8H, and the lower thread 150 guided to the lower thread lead-out hole 8G is For example, even if there is no lower thread guiding auxiliary mechanism such as a wiper mechanism, the lower thread tension spring hole 8H can be easily guided as it is, so that the thread hooking operation can be successfully completed. ing.

The bobbin case open edge 8E, through which the bobbin thread 150 passes when the thread is hooked, is chamfered so that the cross section in the bobbin axial direction becomes curved. Even if it comes into contact with 8E, the thread is not broken, so the reliability of the device can be improved.

The lower thread winding device shown in FIGS.
When the conventional bobbin case shown in FIG. 5 is applied, the bobbin thread 150 stops at the slit groove 8CC in the state shown in FIG. 14, and the re-operation by the wiper mechanism is necessary. That is, the air cylinder 134 is
To move the wiper 130 to the shaft 1 as shown in FIG.
Rotate about 180 ° around 29, slit 8CC
Hooked on the wiper 130,
It is necessary to guide the lower thread portion that has entered the slit 8CC to the lower thread lead-out hole 8GG below the lower thread tension spring 8D, and further to the lower thread tension spring hole 8H located on the left side in the figure. .

The invention made by the present inventor has been specifically described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say, for example, in the above-described embodiment, as shown in FIG.
The chamfer 8a is provided to facilitate the movement of the bobbin case 8 to the thread hooking position 8B on the side of the lower thread tension spring. It goes without saying that it is possible to obtain

Further, the function of moving the bobbin thread 150 to the opening 8A of the bobbin case 8 during winding of the bobbin case 8 may be replaced by another simple structure other than the wiper mechanism, or the bobbin winding device may have a wiper mechanism. If this is not done, a wiper mechanism having a complicated structure is completely unnecessary, and the cost of the apparatus can be reduced.

As described above, the operation of the lower thread 1 can be performed without the wiper mechanism due to the action of the inclination angle θ1 of the slit groove 8C.
50 can be easily moved to the lower thread tension spring hole 8H. Therefore, when the lower thread is wound around the bobbin 7 in the initial operation of winding the lower thread, the shape of the wiper 130 can be made such that the lower thread 150 is securely brought to the opening 8A of the bobbin case. The shape is to move the bending point 130a of the wiper 130 in FIG. 11 upward in the figure. As a result, the lower thread 150 is guided upward to the left from the horizontal state shown in FIG. 11. However, it is possible to prevent the winding failure that is guided to the upper side of the bobbin case 8 due to looseness of the lower thread, thereby improving reliability.

The bobbin case 8 of the present invention is not applied only to the bobbin winding device of the above embodiment. In short, the bobbin case is automatically wound around the bobbin 7 built in the bobbin case 8. At the same time, the lower thread 150 wound around the bobbin 7 and led out from the opening 8A of the bobbin case 8 is passed through a gap 8K between the open end edge 8E of the bobbin case 8 and the outer periphery of the bobbin and a slit thread 8C via a slit groove 8C. 8G, and the lower thread 150 led out from the lower thread lead-out hole 8G is inserted into the lower thread tension spring end 8.
Any lower bobbin winding device that automatically draws a bobbin to the bobbin case 8 by drawing it out from the lower bobbin tension spring hole 8H under the DD can be applied to other bobbin winding devices. Needless to say.

[0076]

As described above, according to the bobbin case of the bobbin winding device according to the first aspect, the inclination angle of the slit groove with respect to the open end portion of the bobbin case through which the bobbin thread passes at the time of threading. The steep inclination makes it possible to easily move the lower thread from the thread hooking position to the lower thread lead-out hole without a lower thread guiding auxiliary mechanism such as a wiper mechanism. Positional relationship in the bobbin axis direction with the hole for tension spring
And set as the lower thread outlet hole is located in the counter-opening edge side of the bobbin case from the lower thread tension spring hole, the lower thread guided to the lower yarn outlet hole, for example, the lower yarn such as wiper mechanism Even if there is no guidance assist mechanism, since it is constituted so that it can be easily guided as it is to the hole for the lower thread tension spring, the thread hooking operation can be successfully completed.

According to the bobbin case of the bobbin winding device of the second aspect, in addition to the first aspect, the bobbin case open end portion through which the bobbin thread passes at the time of threading has a curved cross section in the bobbin axial direction. The chamfering is performed so that even if the lower thread abuts on the open edge of the bobbin case during threading, thread breakage does not occur, so that reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a front view of a lower thread winding device of a sewing machine according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional plan view of FIG.

FIG. 3 is a perspective view of a pulley.

FIG. 4 is a view of FIG. 1 as viewed from the left side.

FIG. 5 is a perspective view of the yarn handling with a moving knife.

FIG. 6 is a plan view of a thread hook lever.

FIG. 7 is a sectional view of a thread hook lever.

8A and 8B show a bobbin case employed in the embodiment, wherein FIG. 8A is a perspective view, and FIG. 8B is a partial cross-sectional view of an open end portion in the bobbin axis direction.

FIG. 9 is a development view of the bobbin case shown in FIG.

FIG. 10 is a front view of a main part showing a yarn clamping operation in an initial state of the device.

FIG. 11 is a front view of a main part showing a bobbin thread winding operation on the bobbin of the above device.

FIG. 12 is a front view of a main part showing a bobbin winding operation and a yarn releasing operation on a bobbin of the same device.

FIG. 13 is a plan view of a main part showing a bobbin thread guiding operation to a slit of a bobbin case of the above device.

FIG. 14 is a plan view of a main part showing a lower thread guiding operation following a lower thread guiding operation to the slit in FIG. 13;

FIG. 15 is a front view of a main part showing a bobbin thread hooking operation under a bobbin thread tension spring of the bobbin case of the above device.

FIG. 16 is a front view of a main part showing a lower thread cutting operation of the above device.

FIG. 17 is a front view of an essential part showing a bobbin thread hanging operation under a bobbin thread tension spring when the conventional bobbin case is applied to the above device.

FIG. 18 is a front view of a yarn tension varying unit applied to the embodiment.

FIG. 19 is a perspective view of an automatic lower thread supply device to which the upper and lower thread winding devices are applied.

FIG. 20 is a front view of FIG. 19;

FIG. 21 is a plan view of FIG. 19;

FIG. 22 is a side view of FIG. 19;

FIG. 23 is a front view showing the relationship between a rotating arm, a forward / reverse lever, and a guide shaft which constitute the automatic upper / lower thread supply device.

FIG. 24 is a perspective view of a bobbin case according to the related art.

FIG. 25 is a development view of the bobbin case shown in FIG. 24.

[Explanation of symbols]

7 bobbin 8 bobbin case 8A bobbin case opening 8C slit groove 8D bobbin thread tension spring 8DD bobbin thread spring end 8E bobbin case open end edge 8e chamfering 8G bobbin thread lead-out hole 8H bobbin thread tension spring hole 8K bobbin Clearance between the open edge of the case and the outer periphery of the bobbin 150 Bobbin thread θ1 The inclination angle of the slit groove with respect to the open edge of the bobbin case

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) D05B 59/00 D05B 57/26

Claims (2)

(57) [Claims] 1. A bobbin thread automatically wound around a bobbin incorporated in a bobbin case, and a bobbin thread wound around the bobbin and led out from an opening of the bobbin case is removed from an open end of the bobbin case by a bobbin case. The bobbin case is guided to the lower thread lead-out hole through the gap with the outer periphery and the slit groove, and the lower thread led out from the lower thread lead-out hole is led out from the lower thread tension spring hole below the lower thread tension spring end. A bobbin case applied to a bobbin winding device configured to automatically perform thread hooking, wherein an inclination angle of a slit groove with respect to a bobbin case open edge portion through which the bobbin thread passes at the time of thread hooking is 30. ° to 45 °, the slit groove is steeply inclined with respect to the bobbin axis direction, and the positional relationship between the lower thread outlet hole and the lower thread tension spring hole in the bobbin axis direction is the lower thread outlet hole. Is the hole for the bobbin thread tension spring A bobbin case of a bobbin winding device set so as to be located on a side opposite to an open edge of the bobbin case. 2. A bobbin case of a bobbin winding device according to claim 1, wherein a bobbin case open end portion through which the bobbin thread passes at the time of threading is chamfered so that a cross section in the bobbin axial direction becomes a curved surface. A bobbin case for a bobbin winding device.