Heat protection circuit

Abstract

The invention relates to a heat protection circuit, which comprises a temperature control switch (TH), a relay select switch (RY1) and a rectifier on the control end of the relay select switch (RY1); the temperature control switch (TH) is connected in series between a load and one end of a power supply; one input end of the rectifier is electrically connected with one end of the power supply, another input end of the rectifier is electrically connected between the load and the temperature control switch through a closing startup unit, the common end of the select switch is electrically connected with the other end of the power supply, the first select end of the select switch is electrically connected with the load, and the second select end of the select switch is electrically connected between another input end of the rectifier and the closing startup unit. When a device is protected by the heat protection circuit due to overheat, the device can be restored only after the power of the device is switched off and then switched on or a memory switch is reset, and therefore the heat protection circuit prevents potential accidents due to reswitch-on caused by the decrease of the temperature of the unattended temperature control switch.

Description

technical field [0001] The invention relates to electronic circuits, in particular to a heating protection circuit. Background technique [0002] At present, heat-prone products such as motors are generally equipped with a protection circuit when the heat generated reaches or exceeds a certain unsafe temperature upper limit. For example, all motors will be equipped with a temperature switch on the body, but after the temperature switch is disconnected, the motor After not working, it will automatically turn on when the temperature drops to the lower limit of the temperature. If the equipment failure is not eliminated, it cannot work, and the user may forget to unplug the power and leave the equipment. At this time, when the temperature switch is turned on, no one is on duty. Accidents and dangers. There are also some circuits controlled by single-chip microcomputers that can keep the recording state connected, but the cost is high. Contents of the invention [0003] The ...

AI Technical Summary

Problems solved by technology

[0002] At present, heat-prone products such as motors are generally equipped with a protection circuit when the heat generated reaches or exceeds a certain unsafe temperature upper limit. For example, all motors will be equipped with a temperature switch on the body, but after the temperature switch is turned off, the motor will After not working, it will automatically turn on when the temperature drops to the lower limit of the temperature. If the equipment failure is not eliminated, it will not work, and the user may forget to unplug the power and leave the equipment. At this time, when the temperature switch is turned on, no one is on duty. Accidents and Dangers

There are also some single-chip microcomputer-controlled circuits that can keep the connection in the recording state, but the cost is high

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