Three hydraulic transmission reversal methods for surface grinders

The reversing method using a stroke reversing valve: a pull rod is connected to the reversing valve core to use the stroke reversing valve for reversing. Use the travel stop on the workbench to push the pull rod to achieve automatic direction change. When the worktable of the surface grinder moves slowly, when the reversing valve reaches the middle position, whether the left and right chambers of the hydraulic cylinder are both filled with pressure oil, or both chambers are filled with return oil, or both chambers are closed, at this time, there is no hydraulic pressure pushing the two chambers of the hydraulic cylinder, which will stop the worktable movement. Therefore, the reversing valve cannot reach the other end, and the so-called "dead point" occurs.

The direction change method using electromagnetic directional valve: the travel switch is driven by the travel block to send a direction change signal, and the direction change valve is changed to the direction change method of electromagnetic directional valve. Activating the electromagnet to push the slide valve to change direction can prevent "dead spots"; But it is a switch type hydraulic valve that opens or closes instantly according to instructions, that is, instantly connects or cuts off the return oil channel. Such a hydraulic reversing system will have a significant impact during reversing.

The directional method using an electro-hydraulic directional valve: the pilot valve is not switched forward, and replacing the electromagnetic directional valve with an electro-hydraulic directional valve constitutes a new directional method. The electro-hydraulic directional valve consists of a pilot valve solenoid spool and a main valve hydraulic spool. Once the direction of the control oil circuit is switched, the main valve core of the surface grinder moves to another working position according to the pre-set speed, and the direction of the main oil circuit changes. The worktable also changes direction, preventing the "dead point" of reversing.