JPH0898979A - Industrial sewing machine drive - Google Patents

Abstract

(57) [Abstract] [Purpose] The control circuit of industrial sewing machine drive devices is mainly controlled by a microcomputer, and employs a programmable method in which sewing parameters are changed in order to respond to various sewing conditions. In order to execute this parameter change, it is necessary to reset the microcomputer, and it has been desired to shorten the time required for this. A timer circuit that starts operation after the AC input power is turned off and turns on after about 1 second, and a regenerative circuit that operates by the outputs of the timer circuit and the protection circuit are provided. When the power is turned off,
Approximately 1 second later, the timer circuit starts up, turns on the regeneration circuit, and forcibly discharges the main smoothing capacitor. After discharging for about 0.2 seconds, the voltage of the control circuit power supply drops to a predetermined value and the reset circuit operates. Eventually, the pilot lamp also goes out and becomes a completely off state. When the power is turned on again, various sewing parameters can be changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device for an industrial sewing machine.

[0002]

2. Description of the Related Art In recent years, drive devices for industrial sewing machines have mainly come to use an AC servo motor as a drive source for reasons such as maintenance-free operation, long life, and comfortable working environment.

A drive device for a conventional industrial sewing machine will be described below. FIG. 2 is a block diagram of a drive device for a conventional industrial sewing machine. In FIG. 2, 1 is a filter circuit,
2 is a rectifier circuit, 3 is a smoothing circuit, 4 is an inverter circuit, 5
Is an AC servo motor, 6 is an inrush current prevention circuit, and 7 is AC
Voltage detection circuit, 8 protection circuit, 9 power supply circuit, 10 control circuit, 11 regeneration circuit, 12 relay drive circuit, 13
Is a solenoid drive circuit.

The operation of the industrial drive device constructed as described above will be described below. First, AC
When the input voltage is applied, the charging current limited by the inrush current prevention circuit 6 charges the capacitor of the smoothing circuit 3. When the power supply circuit 9 rises after being charged for several cycles, the relay drive circuit 12 is turned on by the output of the protection circuit 8, the relay of the inrush current prevention circuit 6 is turned on, and the inrush current prevention resistor is short-circuited. When the charging further progresses and the input value of the DC voltage detection circuit 14 exceeds a predetermined value, the protection circuit 8 reports to the control circuit 10 that the entire device is normal, and enters the standby state. The sewing work is started, the motor runs at high speed,
If the DC voltage value during regeneration exceeds a predetermined value, the protection circuit 8 outputs an ON signal for the regeneration circuit 11 to decrease the voltage value.

When the sewing operation is completed and the AC input voltage is cut, the AC voltage detection circuit 7 outputs an OFF signal to the protection circuit 8.
The relay drive circuit 12 is turned off to restore the inrush current prevention resistor. At the same time, the control circuit 10 prohibits the motor drive and the solenoid drive and saves the memory data of the microcomputer. At this time, the smoothing capacitor stores the electric charge in the standby state, and the control circuit 1
0, the protection circuit 8 and other loads cause spontaneous discharge. When the voltage of the smoothing capacitor gradually drops and the power supply voltage of the control circuit 10 generated by the power supply circuit 9 becomes lower than a predetermined value, the microcomputer mounted in the control circuit 10 is reset and the control device is turned off. Becomes

[0006]

However, in the above conventional structure, it takes a long time to discharge the main smoothing capacitor. Conventionally, the discharge was completed in about 3 seconds, but since the power consumption of the device was reduced, the load of natural discharge was reduced and it became a long time of 7 to 8 seconds.

On the other hand, in order to flexibly change various parameters that determine the sewing conditions, it is necessary to reset the microcomputer of the control device, and it is desired to shorten the time required from power-off to reset.

Further, the fact that the pilot lamp keeps lighting for a long time after the power is turned off may be mistaken for forgetting to turn off the power.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and an object of the present invention is to provide an industrial sewing machine drive which completes the reset of the microcomputer of the control device 1 to 2 seconds after the power switch is turned off.

[0010]

In order to achieve this object, an industrial sewing machine drive apparatus according to the present invention includes a timer circuit that starts operation after the AC input power is turned off and turns on after about 1 second, the timer circuit and the protection. And a regenerative circuit that operates according to the output of the circuit.

In a normal operating state, when the DC voltage rises above a predetermined voltage, the protection circuit turns on the regenerative circuit and lowers it.

When the power is turned off, the timer circuit rises and the regenerative circuit is turned on about 1 second after the power is turned off, and the charge of the smoothing capacitor is forcibly discharged.

[0013]

With this configuration, the timer circuit turns on the regenerative circuit about one second after the power is turned off. Then about 0.2
When the forced discharge continues for a second, the power supply for the control circuit generated in the power supply circuit drops, the reset circuit operates and the microcomputer reset is completed, and the pilot lamp is turned off and the drive device is completely turned off.

[0014]

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 100 is a timer circuit, and the other components are the same as those in the conventional example. The operation of the industrial sewing machine driving device configured as described above will be described with reference to FIG. First, when the power supply voltage is turned off, an off signal is input from the AC voltage detection circuit 7 to the protection circuit 8 to turn off the relay drive circuit 12 and restore the inrush current prevention resistor. The control circuit 10 prohibits motor driving and solenoid driving, and saves the memory data of the microcomputer. The AC input OFF signal of the protection circuit 8 is the timer circuit 100.
Is output to the timer, and the timer starts to operate and then rises in about 1 second. At that time, the saving of the memory data of the microcomputer of the control circuit 10 is set to be completed. When the timer circuit 100 is turned on, the regenerative circuit 11 is turned on to forcibly discharge the DC voltage. After about 0.2 seconds, the power supply voltage of the control circuit 10 drops to a predetermined voltage, the reset circuit operates, the microcomputer is reset, and the pilot lamp is turned off.

[0016]

As described above, according to the present invention, since the regenerative circuit is turned on by the timer circuit which starts operation after the AC input power is turned off and turns on after about 1 second, the discharge time can be greatly shortened. Therefore, the time required for resetting the microcomputer can be shortened from 7 to 8 seconds to 1 to 2 seconds, and the sewing parameters can be changed quickly.

[Brief description of drawings]

FIG. 1 is a block diagram of a drive device for an industrial sewing machine according to an embodiment of the present invention.

FIG. 2 is a block diagram of a conventional industrial sewing machine drive device.

[Explanation of symbols]

 1 Filter Circuit 2 Rectifier Circuit 3 Smoothing Circuit 4 Inverter Circuit 5 AC Servo Motor 6 Inrush Current Prevention Circuit 7 AC Voltage Detection Circuit 8 Protection Circuit 9 Power Supply Circuit 10 Control Circuit 11 Regeneration Circuit 12 Relay Drive Circuit 13 Solenoid Drive Circuit 14 DC Voltage Detection Circuit 100 timer circuit

Claims (1)

[Claims] 1. A filter circuit, a rectifying circuit, a smoothing circuit, an inverter circuit, an AC servomotor, a power supply circuit for generating a plurality of insulated DC voltages, a solenoid drive circuit, and the AC servomotor. And a control circuit for controlling the solenoid drive circuit, an AC voltage detection circuit,
A DC voltage detection circuit, a protection circuit that detects an abnormality in each part and outputs a protection signal to the control circuit, a timer circuit that starts operation after the AC input power is turned off and turns on after about 1 second, the timer circuit, and An industrial sewing machine drive having a regenerative circuit that operates according to the output of a protection circuit.