SU789372A1 - Hydraulic jack - Google Patents

Description

one

The invention relates to lifting machines and can be used in high-capacity jacks.

A hydraulic lift is known, which contains dual hydraulic cylinders, in which two pistons with a drain are installed in series, the cavities of which are connected in pairs through a switchgear with a pump and a tank fl.

The disadvantage of such a device is heavy loads at the end of the stroke of the jack and its bulkiness.

The closest to the proposed technical entity is a hydraulic j rail cylinder containing a hydraulic pump, a tank, a switchgear, a housing with a plunger hydraulic cylinder placed in it, in which the bulkhead and pistons with a common hollow rod fixed to the bottom of the housing are located. connecting the chamber of the forward stroke of the hydraulic cylinder with the distribution device, and the reverse chamber connected with the drain, the upper piston is equipped with a pressure matching valve connecting the pressure cavity with the drain at the end of the lift 2

The disadvantage of such a device is its large size due to the large forces at the end of lowering the jack.

The purpose of the invention is to reduce the overall dimensions of the hydraulic compartment.

The goal is achieved by the fact that the lower chamber of the reverse stroke is connected through a switchgear to the pump and through an overflow valve to the tank, the overflow valve being set to a pressure below the worker;

The drawing shows a schematic diagram of the jack.

Claims (2)

The scheme includes a pumping station 1 and a cylinder 2 of the jack. Pump station 1 contains a tank 3, a hydraulic pump 4 with an engine, a system of valves 5, 6, 7 and 8 and an overflow valve 9. The jack cylinder 2 consists of a housing 10, a plunger 11 with a bottom cover 1 2 and a jumper 13 ,. hollow rod 14 with middle 15 and upper piston 16. Lower 17, upper 18 and middle 1 of the forward running cavity are connected by channels in the hollow rod 14 between themselves and the pipeline 20 through valve 7 with a pump 4. In the body of the upper piston 16 are mounted pressure control valves 21.. The cavity 22 of the upper piston 16 is connected through channel 23 to tank 3, and the cavity 24 is reverse through channel 25, pipe; pipe 26 and 6 is connected to pump 4, besides it is connected through valve 5, overflow valve 9 by drain line 27 with tank 3. The device works as follows. th. To lift the load, the pump 4 is started, opening from valves 5 and 7 and closing valves 6 and 8. At the same time, oil from pump 4 through valve 7 and pipe 20 is fed into cavities 17, 18 and 19. the oil from the cavity 24 through the channel 25 and the pipe 26, the valve 5 and the drain line 27 is discharged into the tank 3. At the end of the stroke of the plunger 11, when lifting the load, the middle jumper 13 presses the matching valves 2I, and the oil from the cavities 18, 17 and 19 is drained c into the cavity 22, through the channel 23 and the drain line 27. in the tank., thereby preventing a blow at the end of the lift. lowering the plunger 1 1 is necessary.) cover valves 6 and 8 and close valves 5 and 7. Oil from pump 4 through valve 6, pipeline 26 enters the return cavity 24, and oil from cavities 17, 18 and 19 is discharged through the pipeline 20, a valve 8 and a drain line 27 to the tank 3. The plunger 11 descends without impact, as part of the liquid is from. When the plunger moves, the pump is poured into the tank 3 through the overflow valve 9, which is set to reduced pressure, and at the end of the stroke all liquid through the valve 9 is discharged into the tank. The use of this device allows to increase the reliability and reduce the specific indicator of metal consumption 3 times. Claims of the invention A hydraulic jack comprising a hydraulic pump, a tank, a switchgear, a housing with a hydraulic cylinder located in it, in which the baffle and pistons with a common hollow rod fixed to the bottom of the housing and connecting the cylinder of the forward stroke of the hydraulic cylinder with the distributor, and reverse gear chambers are located connected to a drain, the upper piston is provided with a pressure matching valve, characterized in that, in order to reduce the overall dimensions, the lower backstop chamber is connected through The control device with the pump and through the overflow valve with tank, the valve is set to a pressure below the worker. Sources of information taken into account during the examination 1. V. Muratov, and others. Hydraulic cylinders. M., Mechanical Engineering, 1966. 2. USSR author's certificate number 179898, cl. In 66 f 1/08, 1965 (prototype).