Sliding vane pump

Abstract

In a sliding vane pump comprising a rotor supported in a housing and having vanes supported radially movably in radially extending slots of the rotor so as to be in contact with the inner surface of a contour ring which is rotatably supported in the housing and forms with the vanes suction pumping and pressure chambers for pumping and pressurizing a fluid, a pressure control arrangement is provided for limiting the pressure in the pumping chamber to the pressure present in the pressure chamber thereby to prevent the generation of noise upon coupling of the pumping chamber with the pressure chamber.

1 . A sliding vane pump, comprising a rotor ( 2 ) with vanes ( 3 ) radially movably supported on the rotor ( 2 ) in circumferentially spaced relationship, a contour ring ( 4 ) extending around the rotor ( 2 ), the vanes being in contact with the contour ring ( 4 ) so as to form between the rotor, the contour ring ( 4 ) and the vanes ( 3 ) suction chambers ( 7 ), pumping chambers ( 8 ) and pressure chambers ( 9 ) for pumping and pressurizing a fluid, the fluid being pre-compressed in the pumping chamber ( 8 ), and an arrangement for providing in the pumping chamber ( 8 ) and in the pressure chamber ( 9 ) essentially the same maximum pump pressure level.  
   
   
       2 . A sliding vane pump according to  claim 1 , wherein the maximum pressure level corresponds to the maximum operating pressure of a system to which the pressurized fluid is to be supplied.  
   
   
       3 . A sliding vane pump according to  claim 1 , wherein the pump includes a fluid suction pocket ( 11 ) and a pressure pocket ( 12 ) and an arrangement ( 13 ) is provided including a valve disposed in a communication path between the fluid pressure chamber ( 8 ) and the fluid suction pocket ( 11 ) for discharging pressurized fluid from the fluid pumping chamber ( 8 ) when the fluid pressure in the fluid pumping chamber ( 8 ) exceeds the pressure of the fluid in the fluid pressure chamber ( 9 ).  
   
   
       4 . A sliding vane pump according to  claim 1 , wherein means are provided for supplying fluid under pressure to an area in the rotor below the vanes for biasing the vanes outwardly into contact with the contour ring ( 4 ).  
   
   
       5 . A sliding vane pump according to  claim 3 , wherein the contour ring ( 4 ) is rotatably supported for changing the angular position thereof relative to the fluid suction, pumping and pressure chambers ( 7 ,  8 ,  9 ) for controlling the pressure in the pumping chamber ( 8 ) relative to the pressure in the pressure chamber ( 9 ).  
   
   
       6 . A sliding vane pump according to  claim 5 , wherein means are provided for rotating the contour ring ( 4 ) based on pressure differences in the suction, pumping and pressure chambers ( 7 ,  8 ,  9 ).  
   
   
       7 . A sliding vane pump according to  claim 6 , wherein a cylinder piston unit ( 20 ) is connected to the contour ring ( 4 ) for rotating the contour ring ( 4 ).  
   
   
       8 . A sliding vane pump according to  claim 5 , wherein a spring is connected to the contour ring ( 4 ) for biasing the contour ring ( 4 ) into a predetermined angular position.  
   
   
       9 . A sliding vane pump according to  claim 7 , wherein the cylinder piston unit ( 20 ) is connected to a control unit ( 22 ) for controlling the angular position of the contour ring ( 4 ).  
   
   
       10 . A sliding vane pump according to  claim 1 , wherein the sliding vane pump includes two suction, two pumping, and two pressure chambers ( 7 ,  8 ,  9 ).