空间大载荷石蜡驱动器研制

石蜡驱动器是当前空间非火工驱动器技术领域的研究热点,现有的空间石蜡驱动器主要采用弹性鞘挤压原理,具有摩擦力大、驱动力小等问题。本文针对这些问题,发展了活塞式空间大载荷石蜡驱动器,该驱动器通过活塞结构有效增大了石蜡液压对驱动杆的作用面积,大幅提高了驱动力;通过双层密封设计和复位弹簧设计,确保了驱动器的密封及复位性能。为了验证该方案,完成了原理样机的制造,开展了摩擦力测试、功能测试、寿命测试等试验。结果表明,采用载荷范围为85~165 N的复位弹簧能推动活塞克服系统摩擦力进行复位,保证了驱动器的自动复位功能;在额定功率40 W(额定电压12 V)下,驱动器的输出位移为6.9 mm,响应时间为20 min,驱动力超过300 N。寿命试验表明,该驱动器寿命超过100次,多次输出位移稳定性好(7 mm左右波动);驱动器密封性能优秀,经历100次作动后,未发现石蜡泄漏。

Development of a large load space-used paraffin actuator

Paraffin actuators have attracted a great deal of attention in the field of aerospace non-pyrotechnic actuators.The current aerospace paraffin actuator usually employs an elastic squeeze boot to push the actuator rod to move,which causes the disadvantages of large friction force and small force output.Motivated by these issues,a piston-type paraffin actuator has been developed in this paper.The actuator effectively enlarges the area that the liquid paraffin can apply pressure on,which greatly enhances the output driving force.The reset function and sealing performance have also been ensured by introducing a double-sealing design and a reset spring.In order to verify the proposed paraffin actuator,a prototype was fabricated.Validation experiments including friction force test,functional test,and life test have been performed.The results show that the reset spring with a designed force range of 85-165 N can successfully overcome the system friction force and push the piston to move,so as to ensure the auto-reset function.Under a rated power of 40 W (rated voltage 12 V),the output displacement of the actuator is 6.9 mm,the response time is 20 min,and the output force is more than or equal to 300 N.Life test shows that the actuator can function 100 times or more,and the output displacement is very stable (around 7 mm).Excellent sealing performance of the actuator has also been proven,since no paraffin leakage has been observed even after 100 times of actuation.