Method of operating a hydraulic pressing unit, and hydraulic pressing unit having a hydraulic pump
AssigneeGustav Klauke GmbH
InventorEgbert Frenken
Life of this patent
Estimating the term…
Abstract
A hydraulic pressing unit includes a hydraulic pump, supply and hydraulic chambers, moving and stationary parts, a restoring spring, and a return valve provided within or attached to a housing. The moving part is displaced from a starting position into a pressing position as a result of filling the hydraulic chamber with a hydraulic medium from the supply chamber by using the hydraulic pump. The return valve is automatically displaced into an open position as a result of a hydraulic pressure corresponding to the pressing position, and the restoring spring moves the moving part. A piston acts on the flow of the hydraulic medium and lowers the pressure such that the return valve is displaced into the closed position.
Claims22
A method of operating a hydraulic pressing unit comprising:
- providing a pressing unit having a hydraulic pump, a moving part, a stationary part and a return valve;
- filling a hydraulic chamber in said pressing unit with hydraulic medium from a supply chamber, said hydraulic chamber being capable of being in fluid communication with said return valve along a flow path;
- displacing the moving part into a pressing position by the buildup of a hydraulic pressure within said hydraulic chamber;
- automatically moving said moving part from the pressing position into an end position under the action of a restoring spring;
- wherein when said return valve is in an open position in which hydraulic medium is allowed to flow through said return valve, said return valve moves to a closed position in which the flow of hydraulic medium is prevented through said return valve after the hydraulic pressure acting on the return valve drops below a certain pressure as a result of the hydraulic medium flowing away from said return valve;
- and wherein means are provided in the flow path between said return valve and said moving part for causing the hydraulic medium to flow away from said return valve.
A hydraulic pressing unit comprising:
- a housing;
- a hydraulic pump provided within said housing;
- a supply chamber provided within said housing and capable of having a hydraulic medium therein;
- a hydraulic chamber provided within said housing and capable of having the hydraulic medium therein;
- a moving part provided within said housing in fluid communication with the hydraulic chamber;
- a restoring spring provided within said housing, said restoring spring capable of acting upon said moving part to cause said moving part to move within said housing;
- a stationary part attached to said housing;
- a return valve provided within said housing and in fluid communication with the hydraulic medium, said return valve capable of being moved to an open position and a closed position, said return valve capable of being in fluid communication with said hydraulic chamber along a flow path;
- the moving part being displaced from a starting position into a pressing position as a result of filling said hydraulic chamber with the hydraulic medium from said supply chamber by using the hydraulic pump, the return valve being automatically displaced into an open position in which hydraulic medium is allowed to flow through said return valve as a result of a hydraulic pressure corresponding to the pressing position, and the moving part returning under the action of said restoring spring, and
- means are provided in the flow path between said return valve and said moving part for causing the hydraulic medium to flow away from said return valve, thereby lowering the hydraulic pressure acting on said relief valve to below a certain pressure, such that the return valve is displaced into the closed position, wherein in said closed position hydraulic medium is prevented from flowing through said return valve.
Dependencies are inferred from the claim text.