JPS5941816Y2 - Solenoid actuation and speed switching device for electric sewing machines - Google Patents

Description

[Detailed description of the invention] The present invention relates to a speed switching circuit for an electric sewing machine and an operating circuit for an electromagnetic solenoid provided for engaging and disengaging the declutching device of the upper shaft of the sewing machine, and operates the upper shaft declutching device. In an electric sewing machine that uses an electromagnetic solenoid to lock and release a locking member, a part of the rectifier circuit for driving the electromagnetic solenoid is connected via a simple switch to rectify the electric sewing machine to rotate at medium speed. commonality,
Another object of the present invention is to provide a circuit that can turn on and off the currents of a sewing machine motor and an electromagnetic solenoid through a common operation using a sewing machine controller or the like.

Embodiments of the present invention will be described below with reference to the drawings. Figures 1 and 2 are schematic diagrams of a declutch device operated by an electromagnetic solenoid according to the present invention, in which 1 is the sewing machine body, 2 is the upper shaft, and 3 is the sewing machine. a motor; 4 is a belt pulley for transmitting the driving force of the sewing machine motor; 5 is a bushing which is coaxially fixed to the upper shaft 2 and has a notched groove 6 parallel to the upper shaft 2 in a part of the circumferential surface; In FIG. 2, the cutout groove is inclined so that the upper part is shallower and the lower part is deeper.

7 is a declutch roller; 14 is a declutch lever which rotatably holds the declutch roller, is pivotally connected to a pivot point 9 and is attached so as to be rotatable within the groove; The roller is biased counterclockwise to guide and move the roller to the clutch engagement position shown by the two-dot chain line in the figure.

Reference numeral 11 denotes an electromagnetic solenoid, and when it is not energized, the pushing blade of the spring 12 keeps the locking member 8 pivoted on the shaft 13 in the position indicated by the two-dot chain line, so that the belt pulley 4 is in the position indicated by the arrow in FIG. In this way, the rotation of the declutch lever 14 is not hindered during clockwise rotation, and the roller 1 is positioned as shown by the two-dot chain line and wedged between the belt pulley 4 and the bottom surface of the inclined notch groove 6 of the bushing 5. When the electromagnetic solenoid 11 is energized, the locking member 8 enters the rotation orbit of the declutch lever 14 as shown by the solid line. Therefore, when the sewing machine rotates from the time when electricity is applied and one side of the declutch lever 14 hits the locking portion 8 and the groove 6 reaches the position shown in the figure, the other side of the declutch lever 14 hits the side of the groove. The sewing machine is forcibly stopped, and the rollers 7 are released from engagement with the inner circumferential surface of the belt sheave 4, as shown by the solid line, so that the belt sheave 4 idles.

FIG. 3 shows a drive circuit for the sewing machine motor 3 and the electromagnetic solenoid 11, and the controller 15 is connected to the alternating current power supply (AC).
and a full-wave rectifier stack, that is, a full-wave rectifier bridge 16 consisting of 14 diodes, are connected in series, and an electromagnetic solenoid 11 is connected to each terminal on the DC side of the rectifier stack via a stitch 17. , one end of the sewing machine motor 3 is connected to the one-power AC side terminal of the rectifier stack 16 which forms the connection point with the controller 15, and the other end of the motor is connected to the contact piece C of the changeover switch 18. One contact a of the changeover switch is connected to the (+) side terminal of the rectifier stack 16, and the other contact a is connected to the other AC side terminal of the rectifier stack 16.

In the configuration shown in FIG. 3, for example, in the case of high-speed normal sewing, when the switch 17 is turned off and the controller 15 is operated with the contact piece C of the changeover switch 18 on the contact side, the sewing machine motor 3 changes from high speed to low speed using an AC sine wave voltage. Speed controlled.

In this state, when the contact piece C is set to the contact a side, the speed of the sewing machine motor 3 is controlled from medium to low speed by the half-wave rectified voltage passing through the diode 16' of the rectifier stack 16, and medium-speed normal sewing is performed. .

Furthermore, when the switch 17 is turned on in this state, the electromagnetic solenoid 11 is driven with a full-wave rectified voltage via the rectifier stack 16.

At this time, to the sewing machine motor 3, in addition to the half-wave rectified voltage passing through the diode 16', a half-wave rectified voltage passing through the electromagnetic solenoid 11 and the diode 16'' of the rectifying stack 16, which are in phase opposite to this, are applied. However, electromagnetic solenoid 1
Since the impedance of the sewing machine motor 3 is generally much higher than the impedance of the sewing machine motor 3, there is almost no motor driving force due to the latter voltage and does not interfere with the motor driving force due to the former voltage. It can control from medium speed to low speed required for sewing control.

Therefore, when the controller 15 is operated, the sewing machine motor 3 rotates and the electromagnetic solenoid 11 operates to move the locking member 8 into the rotation orbit of the declutch lever 14, and the sewing machine rotates, for example, when the needle is at the top dead center. The sewing machine will stop when this is reached.

Then, when the controller 15 is released, the motor stops, the electromagnetic solenoid 11 becomes inactive, and the locking member 8 moves out of the rotational orbit, making preparations for the next rotation of the sewing machine.

Then, by driving the controller 15 again, the sewing machine rotates one more rotation and stops at the top dead center.

According to the present invention as described above, - When sewing needles, each stitch can be stopped at a fixed position easily and reliably by operating it using a conventional controller, and the control device is driven by an electromagnetic solenoid. This can be realized with a simple circuit in which a part of the diode used for motor control is shared for motor control, and it has a great industrial effect.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a declutch device operated by an electromagnetic solenoid according to the present invention, and Fig. 2 is a schematic diagram of a declutching device operated by an electromagnetic solenoid according to the present invention.
The sectional view and FIG. 3 are control circuit diagrams showing an embodiment of the present invention. In the figure, 3 is a sewing machine motor, 11 is an electromagnetic solenoid, and 15 is a sewing machine motor.
1 is a controller, 16 is a full-wave rectifier stack, and 18 is a changeover switch.

Claims (1)

[Scope of utility model registration request] A controller and a full-wave rectifier stack are connected in series to an AC power source, an electromagnetic solenoid is connected to each DC side terminal of the rectifier stack, and one AC side terminal of the rectifier stack is connected to one power terminal of the sewing machine motor. , connect the other terminal of the motor to the contact piece of the changeover switch, connect one contact of the changeover switch to one of the terminals on the DC side, and connect the other contact of the switch to the contact piece of the changeover switch. A solenoid actuation and speed switching device for an electric sewing machine, the device being connected to the other AC side terminal of the rectifying stack.