External driving type quick switch structure

Abstract

An external driving type quick switch structure comprises an upper shell, a lower shell and a conductive plate arranged between the upper shell and the lower shell. An electronic ignition device and apiston are sequentially arranged in the accommodating cavity of the upper shell from top to bottom, and an accommodating cavity is formed in the lower shell below the piston and the conductive plate;the switch structure is characterized in that the conductive plate is recessed towards the accommodating cavity of the lower shell, and a flat-bottomed notch is formed in the accommodating cavity; abreaking notch and a bending notch are formed in the flat bottom of the notch at intervals, and the lower end of the piston is located above the breaking notch. The accommodating cavities in the uppershell and the lower shell meet the requirement that the piston can move into the lower shell from the upper shell. The conductive plate is broken at the breaking notch and falls down along the side wall of a cushion block by taking the bending notch as a rotating shaft, so that a main circuit is disconnected. Impact energy is absorbed through an energy absorption structure arranged between the piston and the cushion block.

Description

technical field [0001] The invention relates to the fields of power control and electric vehicles, in particular to a device for controlling and cutting off a current transmission circuit through an external signal. Background technique [0002] The product of circuit overcurrent protection is a fuse that is blown based on the heat generated by the current flowing through the fuse. The main problem is the matching relationship between the thermal fuse and the load. For example, in the case of new energy car main circuit protection, if the load has a low multiple overload or short circuit, the use of a fuse with a low current specification cannot meet the short-term overshoot of the current, and if the fuse with a high current specification cannot meet the requirements of fast protection Require. In the current lithium battery pack that provides energy for new energy vehicles, the output current is about several times the rated current in the event of a short circuit, and th...

AI Technical Summary

Problems solved by technology

For example, in the case of new energy car main circuit protection, if the load has a low multiple overload or short circuit, the use of a fuse with a low current specification cannot meet the short-term overshoot of the current, and if the fuse with a high current specification cannot meet the requirements of fast protection Require

In the current lithium battery pack that provides energy for new energy vehicles, the output current is about several times the rated current in the event of a short circuit, and the protection time of the fuse cannot meet the requirements, causing the battery pack to heat up and burn.

Due to the heating of the withstand current and the heating and melting of the breaking current, both originate from the current flowing through the fuse. This kind of protective device that uses current heating and fusing cannot withstand a relatively large rated current or withstand a strong short-term overload / impact current. (For example, the short-term high current when the electric vehicle starts or climbs a slope), the breaking speed of a fault current with a certain amplitude is fast enough, or the protection speed of a fault current with a certain amplitude is fast enough to achieve a higher rating current, or withstand large overload / inrush current without damage

[0003] Another problem with thermal fuses is that they cannot communicate with external devices and cannot be triggered by signals other than current, such as vehicle ECU, BMS or other sensors, etc.

However, it still has some shortcomings and defects: the overall size is large, which cannot meet the application environment with high size requirements; the overall weight is heavy, and cannot meet the application environment with high weight requirements; Ineffective thermal power loss is high; the action is slow, the action time of the fast fuse is 10-50ms, and the slow fuse is slower; the resistance to current shock is poor, and the narrow diameter of the melt is very narrow, which cannot withstand long-term, multiple Once the high current impact, it is easy to be blown by the impact current; it cannot be disconnected under low current, and it must reach more than 3 times the rated current to operate; the heat generated during normal operation is large, and the temperature is high, forming a heat source, which needs to be dissipated

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