Hydraulic aggregate for the leakage cavity of a pump

Abstract

The present invention relates to a hydraulic aggregate for a hydraulic controlling and/or regulating device, including a pump having a pump housing that includes a leakage chamber with a leakage bore opening into a hollow space of a lid fixed to the pump housing, said hollow space having a pressure-fluid connection to the atmosphere. The leakage bore is connected to the atmosphere by way of a float valve open in its basic position, and the float valve effects closure of the leakage bore under the effect of hydrostatic pressure in lid.

1 . Hydraulic aggregate for a hydraulic controlling and/or regulating device, including a pump having a pump housing that includes a leakage chamber with a leakage bore opening into a hollow space of a lid fixed to the pump housing, said hollow space having a pressure-fluid connection to the atmosphere, characterized in that the leakage bore ( 1 ) is connected to the atmosphere by way of a float valve ( 2 ) open in its basic position, and in that the float valve ( 2 ) effects closure of the leakage bore ( 1 ) under the effect of hydrostatic pressure in lid ( 3 ).  
     
     
         2 . Hydraulic aggregate as claimed in  claim 1 , characterized in that the float valve ( 2 ) comprises a valve sleeve ( 4 ) which is slidably arranged in a tubular socket ( 5 ) that is inserted into the leakage bore ( 1 ) and extends into the hollow space ( 6 ) of the lid ( 3 ).  
     
     
         3 . Hydraulic aggregate as claimed in  claim 1  or  2 , characterized in that at least one leakage channel ( 7 ) is interposed between the tubular socket ( 5 ) and the valve sleeve ( 4 ), said leakage channel allowing leakage fluid out of the leakage chamber ( 8 ) of the pump to propagate into the hollow space ( 6 ) of lid ( 3 ) when the float valve ( 2 ) adopts its open position.  
     
     
         4 . Hydraulic aggregate as claimed in any one of the preceding claims, characterized in that for forming several leakage channels ( 7 ) the valve sleeve ( 4 ) includes a square outside profile having an end that includes a collar ( 9 ) whereat an annular seal ( 10 ) is arranged for forming a valve seat, said seal ( 10 ) abutting on the tubular socket ( 5 ) and closing the leakage channel ( 7 ) under the effect of hydrostatic pressure.  
     
     
         5 . Hydraulic aggregate as claimed in  claim 4 , characterized in that the end of the valve sleeve ( 4 ) remote from the collar ( 9 ) has a gas-permeable, but fluid-impermeable diaphragm ( 11 ) that fluid-tightly isolates the leakage chamber ( 8 ) in the pump housing from the hollow space ( 6 ) in lid ( 3 ) when the float valve adopts its closed position.  
     
     
         6 . Hydraulic aggregate as claimed in any one of the preceding claims, characterized in that the tubular socket ( 5 ) in conjunction with the float valve ( 2 ) forms a pre-assembled and pre-adjusted independently operable assembly, with sections of the tubular socket ( 5 ) being pressed into the leakage bore ( 1 ) for the purpose of adjusting the float valve ( 2 ).  
     
     
         7 . Hydraulic aggregate as claimed in any one of the preceding  claims 1  to  6 , characterized in that there is an axial distance between the tubular socket ( 5 ) and the inside wall of the lid ( 3 ) which is at least as large as the working stroke of the float valve ( 2 ), the said float valve ( 2 ) in its open position being supported with its collar ( 9 ) on the inside wall of the lid ( 3 ).