Hydraulic lift is also called hydraulic elevator. It refers to an elevator that presses oil into a cylinder through a hydraulic power source to make the plunger move linearly, or directly or indirectly through a wire rope to move the car. Hydraulic elevator is a product integrating machine, electricity, electronics and hydraulic pressure. It consists of the following relatively independent but interrelated systems: pump station system, hydraulic system, guidance system, car, door system, electrical control system, safety Protection system, etc.
Hydraulic drive is an early form of elevator drive. The transmission medium of early hydraulic elevators was water. The incompressible nature of water was used to increase the pressure of the water by pressurizing it. The water with a certain pressure was connected to the cylinder, and the plunger inside the cylinder was lifted to lift the car. The car runs upwards; the drain is opened by the relief valve, and the car descends under its own weight.
However, it is difficult to solve the problem that the water pressure contains air bubbles and the cylinder is rusty. After that, the oil is used as the medium to drive the plunger to perform linear motion. Because the hydraulic elevator has a large lifting force, can provide high mechanical efficiency and low energy consumption, the advantages of use are particularly obvious in the case of short strokes and heavy loads. In addition, because the hydraulic elevator does not have to have a machine room on the roof, the vertical size of the hoistway is reduced, and the building space is effectively used, the application prospect of the hydraulic elevator is relatively broad. Today hydraulic elevators are widely used in parking lots, factories and low-rise buildings. For occasions with large loads, slow speeds and short strokes, the use of hydraulic elevators is more economical and suitable than traction elevators.
Hydraulic elevator operation is divided into up and down. When the elevator descends, open the valve group and use the pressure difference caused by the car ’s own weight [the weight of the passenger (cargo)] to return the hydraulic oil to the hydraulic oil tank to achieve the downward movement of the elevator. At this time, the hydraulic pump station does not consume work, and the car The downward speed is controlled by the size of the valve group opening in the hydraulic system.
When the elevator goes up, the hydraulic pump station provides the power pressure difference required for the elevator to go up. The valve group in the hydraulic system controls the flow of hydraulic oil in the pump. When the hydraulic oil enters the oil chamber in the cylinder, the hydraulic oil pushes the plunger in the hydraulic cylinder. To lift the car to achieve the upward movement of the elevator, the work consumed by the hydraulic pump at this time is the actual work.
The hydraulic system of a hydraulic elevator mainly includes hydraulic pumps, cylinders, hydraulic motors, various types of valves, and connecting pipes and joints.
1. There is no need to set up a machine room with high requirements and cost above the shaft, and the roof can be flush with the roof.
2. Machine room settings are flexible. The hydraulic transmission system relies on oil pipes to transmit power, so the location of the machine room can be set within 20 m from the shaft, and the area occupied by the machine room is only 4 to 5 m².
3. High shaft utilization. Generally, the hydraulic elevator is not provided with a counterweight device, so the utilization rate of the hoistway area can be improved.
4. Low structural strength requirements. Because the vertical load of the hydraulic elevator car such as its own weight and load are all applied to the foundation of the hoistway through the hydraulic cylinder, the building performance requirements for the walls and top of the hoistway are low.
1. Smooth running and comfortable ride. The hydraulic system transmits power uniformly and smoothly, and can realize stepless speed regulation, and the elevator's running speed curve changes gently, so the comfort is better than that of speed regulating elevator.
2. Good safety, high reliability and easy maintenance. The hydraulic elevator is not only equipped with the safety devices of universal traction elevators, but also with the following devices:
1. Overflow valve. Prevents excessive system pressure during upward movement.
2. Emergency manual valve. When a power failure occurs, the car can be lowered to the nearest floor position and the hall and car doors can be opened automatically to ensure that passengers can safely exit the car.
3. Manual pump. When the system fails, the manual pump can be operated to release high pressure oil to make the car rise to the nearest floor position.
4. Pipeline rupture valve. When the hydraulic system pipeline is broken and the car stall drops, the oil circuit can be cut off automatically.
5. Fuel tank oil temperature protection. When the oil temperature in the fuel tank exceeds a certain value, the oil temperature protection device sends a signal to suspend the use of the elevator. When the oil temperature drops, the elevator can be started.
6. Heavy load. The hydraulic system has a large power-to-weight ratio, so an elevator of the same specification can carry a large weight.
7, low noise. The hydraulic system can use low-noise screw pumps. At the same time, the pump and motor can be designed as submersible structure to form a whole pumping station, which can greatly reduce the impact of noise.
8. Good explosion-proof performance. The hydraulic lift adopts low-condensing flame-retardant hydraulic oil. The oil tank is sealed as a whole. The motor and hydraulic pump are immersed in the hydraulic oil, which can effectively prevent the combustion of combustible gases and liquids.
The above content is the related introduction of the hydraulic lift , I hope to help everyone.