电液比例阀课稿.ppt

液压技术社区 液压技术社区 液压技术社区 两-级比例溢流阀 为控制大流量，直动式比例溢流阀能被用来作为一个两级溢流阀（或减压阀）的先导级 To control higher flow rates, the proportional direct acting relief valve can be used as the pilot stage of a two-stage relief (or reducing valve). TWO-STAGE PROPORTIONAL RELIEF VALVE To control higher flow rates, the proportional direct acting relief valve can be used as the pilot stage of a two-stage relief (or reducing valve). BENEFITS OF PROPORTIONAL SYSTEMS 比例系统的优点 远程控制 – 传统系统 在常规系统中为了调整执行器的速度，流量控制阀必须安装在一个方便的或便于接近的位置，这意味着与操纵台连接的液压管路经常运行在高压下。 远程控制 – 比例系统 对于比例系统，控制阀为电子调节，仅需要低功率的电缆连接操纵台和比例阀即可。 With a proportional system however, where control valve adjustment is electronic, only low-power electrical cables need to be connected between the operator’s desk and the valve. PLC 远程控制 – 比例系统 今天更多的是，机械控制被数字电子控制所取代，这里情况也是一样，比例阀的电子控制能力为液压系统和电子控制器之间提供一个简单的接口。 比例压力控制 使用比例方向和压力控制阀意味着机器的所有液压功能（运动和力）能被电子地控制。 电磁阀的反应时间 SOLENOID VALVE RESPONSE TIME A further benefit of proportional valves is the ability to electronically control the speed of operation of the valve. 比例阀地进一步功能是电子控制阀操作速度的能力。 0.015 S SOLENOID VALVE RESPONSE TIME Depending upon its size and voltage supply, a conventional switching solenoid valve will have an energisation response time of approximately 15 milli-seconds. 依据阀的大小和提供的电压，一个传统的开关电磁阀对于一个得电动作的反应时间是15毫秒。 0.040 S SOLENOID VALVE RESPONSE TIME The de-energisation response time will be only slightly slower (typically around 25 ms) since the return spring produces less force than the solenoid . 由于回程弹簧的力小于电磁铁，断电的反应时间稍慢（通常25ms左右）， S 比例阀的反应时间 PROPORTIONAL VALVE RESPONSE TIME 比例阀阀芯的运动速度能被阀电磁铁的供给电子信号确定。通过逐渐地增加或降低信号（叫做斜坡）可以完成几秒的得电和断电时间。 The speed ofmovement of a proportional valve spool however can be determined by the electronic signal fed to the valve solenoid. By gradually increasing or decreasing the the signal (known as ramping), it is possible to achieve energisation and de-energisation response times of several seconds. 1.000 S PROPORTIONAL VALVE RESPONSE TIME 比例阀阀芯的运动速度能被阀电磁铁的供给电子信号确定。通过逐渐地增加