The speed increasing circuit is a circuit device used in servo hydraulic presses to increase the operating speed of the actuator and improve the efficiency of the system. It is commonly used in cases where there is a large flow and low pressure during idling stroke. What are the common types of speed increasing circuits in servo hydraulic presses and their advantages and disadvantages?
With the differential connection speed increasing circuit, there is no need to increase the output flow of the hydraulic pump, which is simple and economical. However, it can only achieve speed increasing in one direction, and the speed increasing ratio is limited by the working area of the two chambers of the hydraulic cylinder. When using this circuit, pay attention to selecting the reversing valve and oil pipe channel according to the larger flow rate during differential operation. Otherwise, the excessive flow resistance may cause the relief valve to open during fast forward, slowing down or failing to achieve differential action. We are able to provide various types of products including relevant servo electric press.
This circuit uses two pumps in parallel to supply oil to the system. Pump 1 is a high-pressure and small-flow pump, and Pump 2 is a low-pressure and large-flow pump. During the empty load motion of the actuator, the load is small, and the unloading valve closes the oil output of Pump 2. The oil flows through the one-way valve and merges with the oil output of Pump 1 to enter the hydraulic cylinder for joint oil supply to the system. During working feed, the load is large, and the system pressure increases. The unloading valve opens to unload Pump 2, and the one-way valve closes, so that only Pump 1 supplies oil to the system. The relief valve controls the oil supply pressure of Pump 1 according to the required working pressure of the system. The adjustment pressure of the unloading valve should be higher than the pressure required during motion, but lower than the pressure required during working feed.
The double-pump oil supply circuit has reasonable power utilization and high efficiency. However, the use of dual pumps increases the cost, and it is suitable for servo hydraulic machines with significant differences in fast and slow speeds.
Regarding the adjustment of parallelism of the hydraulic press for bearing fitting, the parallelism between the slider and the workbench should be adjusted by adjusting the upper beam nut, so as to lay a good foundation for the precision adjustment of the machine. Then adjust the equipment to the pressure state, and tighten the connecting parts between the piston and the movable crossbeam to make it a whole. At this time, the connecting parts between the cylinder and the upper crossbeam should also be fastened.
In this case, the locking nut under the workbench needs to be tightened as much as possible, so that the perpendicularity between the lower plane of the movable crossbeam and the piston rod can determine the parallelism of the hydraulic press. Only when both are perpendicular, can the servo hydraulic press machine be used to obtain accurate results. Adjusting the parallelism of the servo hydraulic press is not complicated or difficult for professionals in this field. And what we need to know is that during the adjustment of parallelism of the hydraulic press, the slider cannot slide down, and after removing the mold, pressure-resistant press blocks must be placed to ensure the smooth progress of this work.