The reason for the wobble in the movable Scissor Lift
When we use the mobile Scissor Lift, we sometimes encounter the phenomenon of unstable speed and acceleration. What is the cause of this phenomenon?Everyone knows how the hydraulic system works and how it works.Hydraulic system is an important part of the Scissor Lift, mainly consisting of motor oil pump, valve plate, overflow valve, safety valve, hydraulic cylinder and hydraulic pipe.When Scissor Lifter have feeding conditions, the electromagnetic coil electricity fittings will smoke box clamping clip arm, to achieve the pressure relay Settings, by pressure relay signals, after rising smoke box in place, the double location under the low transmission part of the shuttle bus to the hydraulic elevator, clamp arm drop, make the cigarette box on low conveyor, the appurtenance clamp arm reaches the highest point and put in place, the double location shuttle bus will smoke box sent to the next level before the conveyor, conveyor to hydraulic lift, high by photoelectric switch signal, lift cylinder will have dropped to the median, waiting for the beginning of the next cycle.
Scissor Lifter lifting speed instability analysis and countermeasures of Scissor Lifter after put into use, can achieve the basic function requirements, from the point of field use, often appear drop cigarette package, it is difficult for rising position detection can't find the median, rising from time to tome noise impact, such as hydraulic cylinder oil leakage phenomenon.On the scene, the lifting speed of the hydraulic cylinder is too fast, which causes the failure rate to increase, which seriously affects the production efficiency.The reasons for lifting the lifting speed of lifting hydraulic cylinder are not stable, and the lifting speed of the hydraulic cylinder is unstable, for many reasons, including the design aspect and the processing manufacturing and the use.
In view of the failure of this hydraulic system, industry experts have come to some conclusions to analyze the reasons for the unstable lifting speed of the Scissor Lift:
(1) lifting hydraulic circuit composition.Oil pump overflow valve, reversing valve, reversing valve, one-way throttle (no throttling), lifting cylinder.
(2) establish velocity rigidity analysis for lifting loop.Flow to the hydraulic cylinder is the flow of the throttle valve through the flow of one-way throttle.The shape of throttling valve and the viscosity of hydraulic oil;AT entering into the flow area of throttling mouth (lifting no throttling);Outlet pressure of hydraulic pump;P1 is the pressure of hydraulic cylinder inlet chamber, to improve the piston area of hydraulic cylinder;According to the index of the shape of the throttle, the velocity of the speed regulating loop can be known, and the output velocity of the hydraulic cylinder will change with the load when the area of the throttle valve is constant.The effect of load on the speed is expressed by the velocity stiffness T. The output speed of the hydraulic cylinder of the elevator is reduced by the increase of load.To make it positive, we add a minus sign.For the Scissor Lift, the higher the speed stiffness of the inlet speed regulation loop, the better the speed stability of the hydraulic circuit.
According to the above analysis, the reasons for the unstable lifting speed of movable Scissor Lift are as follows:
(1) when the load is constant, the smaller the throttle valve inlet, the higher the system speed rigidity.Conversely, the larger the opening area of the throttle, the lower the inlet.
(2) when the load is constant, the speed of the low speed is good. When the load changes, the speed of the load is good.
(3) increase oil supply pressure and increase the effective area of hydraulic cylinder, which can improve the speed stiffness.
In conclusion, the main reason for the failure of the Scissor Lift is the unreasonable design of the hydraulic system to improve the speed regulating circuit.