JPH0732830B2 - Sewing machine bobbin winder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thread winding device for a sewing machine that winds a lower thread around a lower thread bobbin of a sewing machine by using a driving force of a sewing machine drive source that rotates a sewing machine main shaft. Is.

[Conventional technology]

Conventionally, as this type of device, there is known a device having a so-called automatic stop function that automatically stops the bobbin winding operation when a certain amount of the sewing machine is wound on the bobbin.

5 to 7 are views showing a conventional bobbin winder having the automatic stop function.

In the figure, 1 is a base that is removably mounted above the sewing machine arm M with screws 2 and 3, and 4 is a rotating arm that is rotatably mounted with a shaft screw 5 on the lower surface of the base 1. The bearing 4a formed at one end of the rotating arm 4 has a rotary shaft 6
Is rotatably fitted and held. The rotary shaft 6 is loosely inserted in the long hole 1a formed in the base 1,
The lower thread bobbin b is provided at a portion protruding above the elongated hole 1a.
While a holding portion 6a is formed to hold the wheel in the rotational direction, a drive wheel 7 having an outer peripheral portion formed of an annular rubber is fixed to a portion protruding downward from the rotary bearing 4. Further, 8 is a locking plate which is rotatably supported on the lower surface of the base 1 by the shaft screw 5, and the locking plate 8 is interposed between the tip of the locking plate 8 and the base 1. Compression spring 9
Is urged clockwise by FIG. 4 (bottom view).

Reference numeral 10 is a thread winding lever fixed to the upper end of a shaft 11 rotatably fitted in the base 1, and 12 is a rotating body attached to the lower end of the shaft 11 and rotating integrally with the thread winding lever 10. The engaging projection 12a of the rotating body 12 is always in contact with the locking plate 8 and is adapted to fit into the notch groove 8a formed in the locking plate 8 at a predetermined rotation position. There is.

A compression spring 13 is interposed between the rotary arm 4 and the locking plate 8 so that the rotary arm 13 can be prevented from rattling.

Further, in FIG. 5, 14 is a sewing machine spindle, and 15 is this sewing machine spindle.
It is a flywheel fixed to 14 with a stop motion screw 16, and a drive pulley 19 connected to a sewing machine motor (not shown) via a timing belt 18 is integrally attached to one side surface of the flywheel 17. The drive wheel 7 is separated from the side surface of the drive pulley 19 when the rotating shaft 6 is in the initial position, and is joined to the side surface when the rotating shaft 6 is in the bobbin winding position.

When the bobbin b is wound with the yarn from the yarn supply source (not shown) by the yarn winding device having the above-described structure, first, the stop motion screw 16 is loosened to release the connection between the sewing machine main shaft 14 and the flywheel 15. The driving force from the sewing machine motor is the sewing machine spindle.
Block transmission to 14. Then, the lower thread bobbin B is held by the holding portion 6a of the rotary shaft 6, and the lower thread bobbin B is engaged with the end portion of the thread drawn from the thread supply source (not shown). Here, the thread winding lever 10 is rotated so as to come into contact with the cylindrical winding portion B ₁ of the lower thread bobbin b from the initial position shown by the solid line in FIG. 6 (a). That is, it is rotated to the bobbin winding position shown in FIG. Then, with the rotation of the thread winding lever 10, the rotating body 13 also rotates from the initial position shown in FIG. 7 (a) to the thread winding position shown in FIG. 7 (b). As a result, the engaging convex portion 12a is released from the notch groove 8a of the locking plate 8 and presses the locking plate 8 to rotate the locking plate 8 counterclockwise in FIG. The rotation of the locking plate 8 causes the rotation arm 4 connected via the spring 13 to rotate, so that the rotation shaft 6 also rotates and moves to the bobbin winding position, and the drive wheel 7 is joined to the side surface of the drive pulley 19. To do.

Here, when the sewing machine motor is driven and the drive pulley 19 and the flywheel 15 are rotated, the drive wheels 7 joined to the drive pulley 19 rotate, and the rotary shaft 6 rotates to rotate the lower thread bobbin B.
Is rotated, and the yarn from the yarn supply source is wound around the winding portion B ₁ of the bobbin B. This allows the bobbin winding lever 10
Is gradually pushed outward by the wound thread,
It rotates in the counterclockwise direction in FIG. When the winding amount reaches a certain full amount and the thread winding lever 10 reaches the thread winding end position shown by the alternate long and short dash line in FIG. 6 (a), the engaging convex portion 13a of the rotating body 12 rotating together with the lever 10 is reached. But,
To reach the engagement position with the notch groove 8a, the locking plate 8 is rotated clockwise by the urging force of the compression spring 9 in FIG. 6 to engage the notch groove 8a with the engagement protrusion 12a. As a result, the locking plate 8
Returns to the initial position, and at the same time, the rotating arm 4 is also pressed by the pressing portion 8b of the locking plate 8 to return to the desired position, and the rotary shaft 6 and the drive wheel 7 also return to the desired position. As a result, the drive wheel 7 is separated from the drive pulley 19, and the bobbin winding operation is stopped.

As described above, according to the above-described bobbin winding device, the bobbin winding operation is automatically stopped when the winding amount reaches a certain amount without the operator having to take any action. Without having to do it, you can work with peace of mind.

[Problems to be Solved by the Invention]

However, in the above-described conventional bobbin winding device, in order to prevent the needle from being raised and lowered involuntarily during the bobbin winding operation, the stop motion screw is stopped each time the bobbin winding operation is started.
16 must be loosened to release the connection between the sewing machine main shaft 14 and the flywheel 15, and after the bobbin winding, it is necessary to re-tighten the stop motion screw 16 again in preparation for sewing work, resulting in a reduction in work efficiency. There was a problem. Also,
There is also a risk that the operator mistakenly starts the bobbin winding operation without loosening the stop motion screw 16 and is injured by the needle that moves up and down. Further, even if the bobbin winding operation is completed, the sewing machine motor continues to be driven unless the operator presses the stop switch, so that there is a possibility that power is wasted by forgetting to press the stop switch.

The present invention has been made in view of the above-mentioned problems of the prior art, and automatically and intermittently disconnects the sewing machine main shaft from the sewing machine drive source at the start and end of the bobbin winding operation without any operator intervention. It is an object of the present invention to provide a thread winding device for a sewing machine that can eliminate waste caused by idle driving of the sewing machine drive source.

[Means for Solving the Problems]

According to the present invention, a clutch mechanism for connecting and disconnecting a rotary plate that rotates by a drive source of a sewing machine and a main shaft of a sewing machine, and a rotary shaft that holds a bobbin during a bobbin winding operation. A rotation shaft moving mechanism that holds the drive shaft to an initial position in which the drive wheel is separated from the rotating plate when a predetermined amount of thread is wound, and a predetermined value depending on whether the drive shaft is in the initial position. And a control means for controlling the sewing machine drive source and the clutch operating mechanism, the sewing machine drive source is stopped and driven when the rotary shaft reaches the initial position from the bobbin winding position. The clutch mechanism is operated in synchronism with the stop of the power source to connect the rotary plate and the sewing machine main shaft.

[Work]

In the present invention, when a certain amount of thread is wound around the bobbin, the rotary shaft holding the bobbin returns to the initial position,
The drive wheel provided on the rotary shaft separates from the rotary plate to stop the bobbin winding operation. Then, after the bobbin winding operation is stopped, the sewing machine drive source is stopped first, and then the uncoupling sewing machine spindle and the rotary plate are connected during the bobbin winding operation to prepare for the next sewing operation.

Example of Invention

An embodiment of the present invention will be described below with reference to FIGS. The members 1 to 14 and 16 in each figure are the same as those in the conventional art, and the detailed description thereof is omitted.

FIG. 1 and FIG. 2 are views showing each operating mechanism in this embodiment. In the figure, A indicates a rotary shaft moving mechanism for moving the rotary shaft 6 for rotating the bobbin b from the initial position shown in FIG. 4 (a) to the thread winding position shown in FIG. 4 (b). This moving mechanism A comprises 4 and 8 to 13 members, which are the same as those shown in the prior art.

Further, 20 is a switch actuating member fixed to the rotating body 12 that rotates integrally with the bobbin winding lever 10 via the shaft 11 with screws 21 and 22, and has a pressing portion 20a protruding outward. Reference numeral 23 is a micro switch fixed to the lower surface of the base 1, and when the bobbin winding lever 10 is at a desired position, the operating portion 23a is pressed by the pressing portion 20a of the switch operating member 20 to be turned on, and a predetermined electric signal is given. On the other hand, when the bobbin winding lever 10 is in the bobbin winding position, the micro switch 23 and the switch actuating member 20 constitute the detecting means B.

24 is a flywheel fixed to the sewing machine main shaft 14 with a stop motion screw 16, and 25 is a cylindrical spring bearing that is loosely inserted into the outer peripheral surface of a cylindrical boss 24a formed at the center of the flywheel 24. Inner peripheral surface of the spring bearing 25 and the boss 24a
The coil spring 26 is inserted in the gap between the outer peripheral surface of the
Both ends of the coil spring 26 are respectively provided with a spring receiver 25 and a boss 24.
It is locked to a and. A drive pulley 27 is provided separately from the flywheel 24, which is rotatably inserted in the sewing machine main shaft 14, and is connected to a sewing machine motor (not shown here) as a drive source via a timing belt 28. Further, the cylindrical boss 27a formed in the center of the drive pulley 27 is inserted into the coil spring 26, and the coil spring is always provided.
Close to 26. Therefore, when the drive pulley 27 rotates due to the driving of the sewing machine motor, its rotational force is always
It is transmitted to the flywheel 24 through the coil spring 26, and
The main shaft 14 of the sewing machine is adapted to rotate together with 24.

Further, 28 is an electromagnetic solenoid whose actuating portion 28a moves up and down in response to a control signal from a control means which will be described later, and 29 is a locking member which rotates about a shaft 29a in response to up and down of the actuating portion 28a of this electromagnetic solenoid 28. When the operating portion 28a descends, the operating portion 28a rotates clockwise in FIG. 1, and a hook-shaped engaging portion 29a formed at the tip thereof has an engaging projection 25a formed on the outer peripheral portion of the spring receiver 25. Is adapted to engage with. Then, when the engagement portion 29b engages with the engagement protrusion 25a and locks the rotation of the spring receiver 25, the diameter of the coil spring 26 inserted therein is increased, and the diameter of the coil spring 26 with the boss 27a of the drive pulley 27 is increased. Since a gap is generated between the sewing machine main shaft 14 and the drive pulley 27, the connection state is released, and even if the drive pulley 27 rotates, its rotational force is not transmitted to the sewing machine main shaft 14, and the above 25, 26,28
And 29 form a clutch mechanism C.

FIG. 3 is a diagram showing a control system circuit in this embodiment, in which 30 is a CPU 31 and ROM 32, RAM 33 as control means.
A well-known microcomputer equipped with
Various signals from the keyboard 34, as well as output signals from the microswitch 23 are input to the CPU 31. Further, on the output side of the CPU 31, drive circuits for the sewing machine motor 35, which is a sewing machine drive source, and the electromagnetic solenoid 28 are provided.
36 and 37 are connected.

The operation will be described based on the above configuration.

When the bobbin winding operation is not performed, the bobbin winding lever 10 is at a position away from the rotary shaft (initial position) as shown in FIG. 4 (a).
Set to. At this time, the engaging convex portion 4a of the rotating body 4 is engaged with the notch groove 8a of the locking plate 8 as in the conventional device, and the drive wheel 7 is held at a position separated from the drive pulley 27. . Further, in this state, the micro switch 23 is not in contact with the pressing portion 20a of the switch operating member 20,
Since it is FF, the operating portion 27 of the electromagnetic solenoid 28 is held in the raised position, and the engaging portion 29a of the locking member 29 has the spring bearing 2.
It is held at a position separated from the engaging protrusion 25a of the fifth member. Therefore, the sewing machine main shaft 14 and the drive pulley 27 are in a connected state, and the needle can be moved up and down by driving the sewing machine motor 35.

Now, when the bobbin thread bobbin b is attached to the rotary shaft 6 and the thread winding lever 10 is rotated to the thread winding position as shown in FIG. 4 (b), the switch operating member 20 rotates together with the rotating body 12, Since the pressing portion 20a presses the actuating portion 23a of the micro switch 23, the switch 23 is turned on and sends a predetermined electric signal. In response to this electric signal, the CPU 31 turns on the electromagnetic solenoid 28 and rotates the locking member 29 to engage the engaging portion 29a.
Is engaged with the engagement protrusion 25a of the spring receiver 25. As a result, the connection between the sewing machine main shaft 14 and the drive pulley 27 is released. Also, at this time, with the rotation of the bobbin winding lever 10,
Since the engaging convex portion 4a of the rotating body 4 is removed from the cutout groove 8a of the locking plate 8, the drive wheel 7 is driven in the same manner as the conventional device.
Join on one side of 27. When the sewing machine motor 35 is driven in this state, the drive wheels 7 are rotated in accordance with the rotation of the drive pulley 27, the bobbin bobbin b is rotated together with the rotary shaft 6, and the yarn is wound around the winding part b _1. Being done. In this bobbin winding operation, since the sewing machine main shaft 14 is disconnected from the drive pulley 27, it does not rotate and the needle does not move up and down.

After that, the thread is wound around the lower thread bobbin b by a certain amount, and when the thread moves the thread winding lever 10 to a predetermined full position, the thread winding lever 10 moves in the same manner as the conventional device.
Is returned to the desired position by the urging force of the drive wheel 7, the drive wheel 7 is separated from the drive pulley 27 accordingly, and the bobbin winding operation is automatically stopped. Further, when the bobbin winder lever 10 returns to the desired position, the operating portion 20a of the switch operating member 20 separates from the micro switch 23, and the micro switch 23 changes from ON to OF.
Switch to F. In response to this, the CPU 31 first sends a stop signal for the sewing machine motor 35 to the sewing machine motor drive circuit 36. Then, after the sewing machine motor 35 and the drive pulley 27 are completely stopped, an OFF signal is sent to the solenoid drive circuit 37 to turn off the electromagnetic solenoid 28.

As a result, the locking member 8 is separated from the spring bearing 25, and the sewing machine main shaft 14 is connected to the drive pulley 27. At this time, since the drive pulley 27 is already in the stopped state, the sewing machine main shaft 14 does not rotate due to the connection with the drive pulley 27, and there is no fear that the needle will be inadvertently raised and lowered.

Further, since the sewing machine motor 35 is automatically stopped after the bobbin winding operation is completed, there is no unnecessary power consumption and the running cost can be reduced.

In the above embodiment, after the CPU 31 sends the stop signal, it is determined whether the sewing machine motor 35 and the drive pulley 27 are completely stopped by the time from when they receive the stop signal until they are completely stopped. May be measured in advance and whether or not the time has elapsed may be measured. Alternatively, the drive pulley 27 or the like may be provided with a sensor or the like for detecting its rotation and the output thereof may be used. .

〔The invention's effect〕

As described above, according to the bobbin winding device for a sewing machine of the present invention, the bobbin winding operation can be automatically stopped when a certain amount of the bobbin is wound on the bobbin winding machine, and the sewing machine at the end and start of the bobbin winding operation. Since the main shaft and the sewing machine drive source can be automatically connected and disconnected via the clutch mechanism, the work efficiency is greatly improved and high productivity is obtained. Further, since the sewing machine main shaft and the sewing machine drive source are connected after the sewing machine drive source is stopped, there is no risk of the needle moving up and down inadvertently at the time of connection, and work safety can be improved. Further, since the sewing machine drive source is automatically stopped after the bobbin winding operation is completed, there is no waste of power consumption, and the running cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an operating mechanism in one embodiment of the present invention, FIG. 2 is an exploded perspective view of what is shown in FIG. 1, and FIG. 3 is a block diagram showing a control system circuit in the same embodiment. FIGS. 4 (a) and 4 (b) are bottom views showing the operating state of those shown in FIGS. 1 and 2, and FIG. 5 is an exploded perspective view showing a conventional thread winding device for a sewing machine, and FIG. (A), (b)
FIG. 7 is a plan view showing an operating state of the one shown in FIG. 5, and FIGS. 7 (a) and 7 (b) are bottom views showing operating states in respective states of FIGS. 6 (a) and 6 (b). A ... Rotary axis moving mechanism B ... Detecting means C ... Clutch mechanism 6 ... Rotating axis 6a ... Insertion part 7 ... Drive wheel 14 ... Sewing machine spindle 27 ... Rotary plate 31 ... CPU (control means) 35 …… Sewing machine motor (sewing machine drive source)

Claims (1)

[Claims] 1. A rotating plate which is rotated by a driving source of a sewing machine, a clutch mechanism which connects and disconnects the rotating plate and a main shaft of a sewing machine, and a holding portion which holds a cylindrical bobbin so as to be locked in a rotation direction. And a driving shaft fixed to the lower end of the sewing machine arm, and a rotating shaft held by the sewing machine arm so that the driving wheel can move from a winding position where it joins the rotating plate to an initial position where it is separated from the rotating plate. A rotary shaft moving mechanism for holding the rotary shaft at the spool winding position during the spool winding operation and for moving the rotary shaft to a desired position when a predetermined amount of spool is wound on the spool; Detecting means for sending a predetermined electric signal depending on whether or not it is in a position, and when the rotating shaft reaches the initial position from the bobbin winding position, the electric signal from the detecting means is received to stop the sewing machine drive source. It Rutotomoni, in synchronization with stopping of the drive source actuates the clutch mechanism, sewing machine winding device being characterized in that a control means for connecting the rotary plate and the main shaft.