Memory metal pin puller with high shear resistance

Abstract

The invention provides a memory metal pin puller with high shear resistance. In the locking state, the driving spring is completely compressed, the balls keep balance under the combined action of the sliding sleeve, the retainer and the sliding pin, the sliding pin is restrained by the balls to be kept in the extending state, and movement of the separation structure is limited. When the pin is pulled out, the SMA wire is powered on, the SMA wire shrinks after being heated, the sliding sleeve is driven to move upwards, the ball loses balance and falls into the containing space in the lower portion of the sliding sleeve, the sliding pin shrinks into the retainer under the action of the pressing force of the driving spring, pin pulling is completed, and the reset spring is fully compressed; during resetting, the sliding pin is pulled out by utilizing a resetting tool, the resetting spring pushes the sliding sleeve to move downwards, the ball returns to the balance position, and the pin puller enters a locking state again. The memory metal pin puller is advantaged in that a shaft hole type matched sliding pin-retainer structure and an indirect driving mode are adopted, the pin puller has advantages of being high in matching precision, large in bearing capacity, smooth in pin pulling, high in reliability and the like, and the working process of the pin puller can be monitored in real time and controlled in a closed-loop mode.

Description

technical field [0001] The invention relates to the technical field of aircraft unlocking mechanisms, in particular to a pin puller driven by memory metal. Background technique [0002] During the working process of the aircraft, especially the spacecraft, it is necessary to restrict a certain state or some parts, and release the restriction according to the instruction after reaching the specified working condition. This function is realized by the unlocking device. At present, such unlocking devices mostly rely on explosive bolts (also known as pyrotechnic bolts) and paraffin drivers to realize the locking and unlocking functions. Explosive bolts will produce a large impact during the unlocking process and cause pollution problems, which will have a great impact on the attitude control of the aircraft and precision equipment; There is a possibility of accidental ignition, so its reliability in use is necessarily limited. The paraffin driver has small impact and can be us...

AI Technical Summary

Problems solved by technology

[0007] (3) The driving spring acts directly or approximately directly on the sliding pin, without considering the uneven pressing force of the spring. Once the pressing force of the driving spring transmitted to the sliding pin is uneven, it is easy to cause the sliding pin to slide poorly question;

[0008] (4) Lack of real-time monitoring and control of the unlocking process

The status output and feedback design are not carried out, and the status signal of whether the pin removal is successful cannot be output, and the closed-loop control of the operation of the SMA wire heating circuit is not carried out, which may cause the SMA wire to overheat and be damaged

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