Reversing circuit of double acting cylinder controlled by three position five way valve
May 17, 2021
Reversing circuit of double acting cylinder controlled by three position five way valve
Figure a shows the reversing circuit with the middle closed three position five way valve (type O), which is suitable for the situation that the piston stops in the middle of the stroke. But because of the compressibility of the gas, the piston stop position accuracy is poor, and there is no leakage in the circuit and valve.
Fig. B shows the reversing circuit with middle pressure relief three position five way valve (Y type). When the piston stops, the circuit can use external force to push the piston to move freely (if manual device can be added). Its disadvantage is that the piston inertia has a great influence on the stop position and is not easy to control. Generally, it can not be used in lifting system.
Figure C shows the reversing circuit of the double piston rod cylinder controlled by the middle pressurized three position five way valve (P type). This circuit is suitable for small piston area and requires the piston to stop quickly in the middle of the stroke. Its disadvantage is that if the cylinder is a single piston rod, due to the effect of "differential pressure", when the system is connected with air source and there is no control signal, the cylinder will slowly extend. Also, it can not be used in lifting system.
