Safe torque turn-off function circuit and control method

Abstract

The invention provides a safe torque turn-off function circuit and a control method. The function circuit comprises a first safe torque turn-off STO branch, a control element, a pre-driving element and a power device. Wherein a power supply pin of the pre-driving element is connected with the output end of the control element, and the output end of the pre-driving element is connected with the power device; the control element is used for acquiring the state of the first STO branch; under the condition that the state of the first STO branch is the off state, a first turn-off signal is generated, and the first turn-off signal is used for cutting off a power supply of the pre-driving element so as to turn off the power device. A switch in an existing circuit is replaced by a control element, no series switch is arranged on a bus, in this way, no extra loss is increased, no extra size is occupied, safe torque turn-off is achieved through the control element, the power supply current of the control element is far smaller than that of the switch, the circuit loss is greatly reduced, and the reliability of the circuit is improved. And the size of the control element is smaller than that of the switch, so that the product size is reduced.

Description

technical field [0001] The present application relates to the technical field of automation control, and relates to but not limited to a safe torque off function circuit and control method. Background technique [0002] With the improvement of people's living standards, there are more and more human-machine collaboration scenarios, and the safety of collaborative robots, automated guided vehicles (AGV, Automated Guided Vehicle), mobile robots and other products is very important to people. When the user's personal safety is threatened, the inverter or servo driver is generally powered off by pressing the emergency stop button, so that the motor stops outputting torque and the machine stops running, so as to prevent the accidental movement of the machine from causing harm to the human body. [0003] In order to prevent personal injury accidents caused by product accidents, the Safe Torque Off (STO, Safe Torque Off) function has been designed for drive equipment such as invert...

AI Technical Summary

Problems solved by technology

The current solution connects the switch in series to the busbar of the power device, which causes a large loss during normal operation, and the volume of the high-current switch cannot be ignored

If the power device is turned off by directly cutting off the bus power of the system, it will cause the micro control unit (MCU, Microcontroller Unit) to lose power at the same time

It is very troublesome to re-adjust the zero position of the robot to restart after a power failure. It often takes a long time to restart the machine, especially for high-power inverters or drives, and it often takes a long time to turn on and off the power of these machines. efficiency

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