Device capable of adjusting opening degree of cartridge valve automatically

A device capable of adjusting the opening degree of a cartridge valve automatically comprises an ejection rod, a cushion plate, a cartridge valve cover, a speed reducer and an encoder. The cushion plate, the cartridge valve cover, the speed reducer and the encoder are connected in a matched mode. The ejection rod is arranged in the cushion plate and the cartridge valve cover at the same time in an inserted mode. The speed reducer is in transmission connection with the ejection rod. An adjusting rod is arranged inside the cartridge valve cover through a bearing mechanism. One end of the adjusting rod is in threaded connection with the ejection rod, and the other end of the adjusting rod is in transmission connection with the speed reducer. The speed reducer drives the ejection rod to move back and forth through the adjusting rod. The bearing mechanism comprises a conical bearing and a plane bearing which are arranged on the adjusting rod. By means of the device, the opening degree of the cartridge valve can be controlled well, and meanwhile an ejection rod of a traditional control device is prone to being stuck is solved; the speed of a hydraulic system can be controlled conveniently. The structure is simple, the device can be used for assembling assemblies independently and is applicable to the production of production lines; in addition, a lubricating device is added, so the device can be durable and widely applicable to speed control over various hydraulic executing elements.