为了提高电液伺服阀的频率响应特性,采用响应速度快、输出力大、刚性好的积层式压电驱动器作为伺服阀的前置级电-机械转换器.采用杠杆放大的方式对压电驱动器的输出位移进行放大,保证足够的流量输出;采用直接驱动阀芯的方式增强了抗污染能力以及动态响应特性;功率级滑阀采用内置方式,用单个压电叠堆实现了滑阀的双向控制.试制了压电伺服阀的样机,并对样机进行了静、动态测试.得出该阀的频宽大于1.2 kHz,流量为5.7 L/m in,抗污染能力达到ISO 4406 18/15.
The pre-stage driver of servo valve adopted a multilayer piezoelectric actuator which has fast response, large output force and high rigidity to improve its characteristics of frequency response. The output displacement of the multilayer piezoelectric actuator was amplified by a lever. A sufficient flow rate and the ability of anti-pollution was improved by the direct drive method. The power level spool valve adopted a build-in manner, and the double direction control of spool was realized by a single piezoelectric actuator. A prototype of piezoelectric servo valve was manufactured and its static and dynamic characteristics were tested. Results show that the bandwidth of the piezoelectric servo valve exceeds 1.2 kHz, the flow rate is 5.7 L/min and the ability of anti pollution reaches ISO 4406 18/15.