Current overload protection method

Abstract

The invention discloses a current overload protection method comprising the steps that: when the current is overloaded, an overload sensing member generates heat, thermally expands a thermal expansionand contraction fluid, and switches to an overloaded state; a top pillar in the overload sensing member is in contact with a trigger mechanism, triggers the trigger mechanism, and switches a restriction mechanism from a restricted state to a released state, and a circuit connecting member switches to a disconnected state under the effect of the elastic force of a disengaging spring therein such that a circuit is disconnected; a user eliminates an overload fault and stilly places the thermal expansion and contraction fluid for a period of time, the thermal expansion and contraction fluid is restored to an original state after cooled, and the overload sensing member switches to a normal state; the user can press the circuit connecting member with a hand to switch the circuit connecting member to a closed state, switch the restriction mechanism to the restricted state, and restore the circuit to the normal state; the user can press a power-off rod with the hand to trigger the trigger mechanism, so that the circuit is manually disconnected by the user.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a circuit current overload protection method. Background technique [0002] With the development of industrial technology, power supplies and various electrical appliances have penetrated into various fields of people's daily life and work. With the increasing use of various electrical appliances, the safety problems of using electrical appliances have become increasingly prominent. Generally, the electrical equipment will be connected in series with the overload protector. The overload protector will cause the bimetal sheet to be heated and deformed by the current overload and separate the dynamic and static contacts, so as to achieve the purpose of protecting the electrical equipment. However, in some loads that change frequently The equipment will cause the overload protector to cut off the current frequently, and the elastic recovery of the bimetal is limited. After exceeding the elas...

AI Technical Summary

Problems solved by technology

[0002] With the development of industrial technology, power supplies and various electrical appliances have penetrated into various fields of people's daily life and work. With the increasing use of various electrical appliances, the safety problems of using electrical appliances have become increasingly prominent. Generally, the electrical equipment will be connected in series with the overload protector. The overload protector will cause the bimetal sheet to be heated and deformed by the current overload and separate the dynamic and static contacts, so as to achieve the purpose of protecting the electrical equipment. However, in some loads that change frequently The equipment will cause the overload protector to cut off the current frequently, and the elastic recovery of the bimetal is limited. After exceeding the elastic recovery limit, it is likely to cause double-plate bounce fatigue, or contact welding due to abnormal current 1. The adhesion causes the overload protector to fail to work normally. These reasons lead to the failure of the bimetal sheet to be heated and deformed normally, causing the overload protector to fail. For this reason, the inventor designed a protector that adopts a thermal expansion automatic circuit breaker, which can automatically sense the circuit Whether the current is overloaded determines whether to cut off the power supply, the circuit reset only needs the user to manually press the recovery lever, which greatly increases the safety performance, and at the same time uses the heat expansion and contraction fluid as the medium, which greatly prolongs the service life of the protector

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