What is the principle of the support mechanism of the scissor lift?
The piston of the hydraulic cylinder moves downward (that is, the weight drops). The hydraulic oil enters the upper end of the hydraulic cylinder through the explosion-proof electromagnetic reversing valve, and the return oil at the lower end of the hydraulic cylinder returns to the oil tank through the balance valve, hydraulic control check valve, throttle valve, and explosion-proof electromagnetic reversing valve. In order to make the heavy objects fall smoothly and the brakes are safe and reliable, a balance valve is installed on the oil return line to balance the circuit and maintain the pressure so that the descending speed is not changed by the weight. The throttle valve adjusts the flow rate and controls the lifting speed. In order to make the brake safe and reliable, and prevent accidents, a hydraulically controlled one-way valve, that is, hydraulic lock, is added to ensure that the hydraulic pipeline can be safely self-locked when the hydraulic pipeline bursts accidentally. An overload sound-activated alarm is installed to distinguish overload or equipment failure.
working principle
The hydraulic lifting device controls the direction of movement of the two cylinders. If the workbench 1 is to be raised, the reversing valve 7 is set to the right position, and the hydraulic oil discharged from the pump 10 is supplied to the rod cavity of the auxiliary cylinder 4 through the check valve 9, the speed regulating valve 8 and the reversing valve 7 At this time, the hydraulic control check valve 6 is opened, so that the hydraulic oil in the rodless cavity of the auxiliary cylinder 4 flows into the rodless cavity of the main cylinder 3 through the hydraulic control check valves 6, 5, and the main cylinder 3 has The hydraulic oil in the rod cavity flows back to the oil tank 18 through the reversing valve 7, the two-position two-way reversing valve 14 and the throttle valve 15, so that the piston rod of the auxiliary cylinder 4 drives the counterweight 2 down, and the main cylinder The piston rod of 3 drives the worktable 1 up. This process is equivalent to transferring the potential energy of the counterweight 2 to the method. After the large-tonnage components are assembled on the ground, the whole is lifted to a predetermined height and installed in place. The installation process is simple and quick, and safe and reliable. In our country, this technology has been successfully applied in the reliability and durability test of the air control system since the end of the 1980s. In addition, it is necessary to check the pros and cons of various control algorithms and control strategies of the computer control system to provide a basis for actual improvement to obtain the best improvement effect. To this end, a hydraulic synchronous lifting test bench for large-scale components was designed. The test bench includes three parts: the hydraulic synchronous lifting test bench. Hydraulic loading test bench and computer control system. This article only describes the function of the hydraulic synchronous lifting test bench and its debugging test. When the lifting workbench carries the workpiece up, it needs the hydraulic cylinder to provide driving force, that is, the hydraulic cylinder outputs energy to the workbench; while the workbench carries the work piece down, its potential energy will be released.
It is necessary for the hydraulic elevator to perform a simulation test on the hydraulic synchronous lifting equipment before the actual project is implemented. The tests include: synchronous lifting cylinders, hydraulic pumping stations, jacks and other loading tests and pressure tests, as well as sensor detection systems.
