Valve arrangement

Abstract

The invention concerns a valve arrangement ( 7 ) comprising a flow path ( 11 ) connecting an inlet ( 9 ) and an outlet ( 10 ), a closing means ( 12 ) arranged in said flow path ( 11 ), a resetting means and a first pressure in a first pressure chamber ( 14 ) acting in a closing direction on said closing means ( 12 ), a pressure of said outlet ( 10 ) and a second pressure in a second pressure chamber ( 18 ) corresponding to a pressure of said inlet ( 9 ) when said closing means ( 12 ) is closed acting in opening direction on said closing means ( 12 ), said first pressure chamber ( 14 ) being connectable to the outlet ( 10 ) via an auxiliary valve ( 13 ). It is intended to keep small a pressure pulse when opening the valve arrangement ( 7 ). This is achieved in that the closing means ( 12 ) having a first opening state (A) and a second opening state (B), a flow resistance of said closing means ( 12 ) in said first opening state (A) being larger than a flow resistance of said closing means in said second opening state (B).

What is claimed is: 
     
         1 . A valve arrangement comprising a flow path connecting an inlet and an outlet, a closing means arranged in said flow path, a resetting means and a first pressure in a first pressure chamber acting in a closing direction on said closing means, a pressure of said outlet and a second pressure in a second pressure chamber corresponding to a pressure of said inlet when said closing means is closed acting in an opening direction on said closing means, said first pressure chamber being connectable to the outlet via an auxiliary valve, wherein the closing means has a first opening state and a second opening state, a flow resistance of said closing means in said first opening state being larger than a flow resistance of said closing means in said second opening state, wherein said closing means is moved into the first opening state by a pressure difference between the second pressure chamber and the first pressure chamber, and wherein said closing means is moved from the first opening state to the second opening state by a pressure at the outlet which exceeds a predetermined value. 
     
     
         2 . The valve arrangement according to  claim 1 , wherein said resetting means comprises at least a spring. 
     
     
         3 . The valve arrangement according to  claim 1 , wherein said closing means comprises at least a first valve element and a second valve element, 
     
     
         4 . The valve arrangement according to  claim 3 , wherein said first pressure chamber and said second pressure chamber are connected via an orifice running through said first valve element. 
     
     
         5 . The valve arrangement according to  claim 3 , wherein said first valve element together with a first valve seat form a valve means, said second valve element together with a second valve seat form a throttling means, and the valve means and the throttling means are connected in series. 
     
     
         6 . The valve arrangement according to  claim 5 , wherein said first valve element is slidingly arranged around said second valve element, said second valve element protrudes through said first valve seat, and said second valve seat is formed by a ring bearing said first valve seat. 
     
     
         7 . The valve arrangement according to  claim 3 , wherein the resetting means comprises a first spring acting on said first valve element in the closing direction and a second spring acting on said second valve element in the closing direction. 
     
     
         8 . The valve arrangement according to  claim 3 , wherein said second valve element comprises a moving restrictor stopping a movement of said second valve element in closing direction. 
     
     
         9 . The valve arrangement according to  claim 1 , wherein said first pressure chamber is connected with said outlet via a second orifice, and said second valve element together with a second valve seat are forming a second valve means arranged parallel to said second orifice. 
     
     
         10 . The valve arrangement according to  claim 9 , wherein said second valve element is actuatable by a pressure at said outlet. 
     
     
         11 . The valve arrangement according to  claim 1 , wherein a third valve means is arranged between said inlet and said outlet opening a restricted flow passage when it is loaded by said first pressure in said first pressure chamber which loading is controlled by said auxiliary valve. 
     
     
         12 . The valve arrangement according to  claim 11 , wherein said second valve element opens a passage between said first pressure chamber and said outlet when the pressure at said outlet exceeds a predetermined value. 
     
     
         13 . A valve arrangement comprising:
 a flow path connecting an inlet and an outlet;   a closing means arranged in said flow path, the closing means including a first opening state and a second opening state, a flow resistance of said closing means in said first opening state being larger than a flow resistance of said closing means in said second opening state;   a resetting means biasing the closing means in a closing direction,   a first pressure chamber connected to the inlet, the first pressure chamber configured such that a first pressure in the first pressure chamber acts in the closing direction on said closing means;   a second pressure chamber connected to the inlet, the second pressure chamber configured such that a second pressure in the second pressure chamber acts in an opening direction on said closing means;   a third pressure chamber in connection with the outlet, the third pressure chamber configured such that a third pressure in the third pressure chamber acts in an opening direction on said closing means; and   an auxiliary valve connecting the first pressure chamber to the outlet, the auxiliary valve being movable between a closed state and an open state;   wherein the auxiliary valve is configured such that in an open state, the first pressure in the first pressure chamber decreases, thereby creating a pressure difference between the second pressure chamber and the first pressure chamber which overcomes the resetting means biasing the closing means in a closing direction and moves the closing means into the first opening state;   wherein the auxiliary valve is configured such that in an open state, a pressure at the outlet increases, thereby increasing the third pressure at the third pressure chamber and creating a pressure difference between the third pressure chamber and the first pressure chamber which overcomes the resetting means biasing the closing means in a closing direction and moves the closing means into the second opening state.   
     
     
         14 . The valve arrangement according to  claim 13 , wherein the second opening state of said closing means is established by a pressure at the outlet which exceeds a predetermined value. 
     
     
         15 . The valve arrangement according to  claim 13 , wherein said closing means comprises at least a first valve element and a second valve element, 
     
     
         16 . The valve arrangement according to  claim 15 , wherein said first pressure chamber and said second pressure chamber are connected via an orifice running through said first valve element. 
     
     
         17 . The valve arrangement according to  claim 15 , wherein the resetting means comprises a first spring acting on said first valve element in the closing direction and a second spring acting on said second valve element in the closing direction. 
     
     
         18 . The valve arrangement according to  claim 17 , wherein the closing means moves into the second opening state when the pressure differential between the third pressure at the third pressure chamber and the first pressure at the first pressure chamber is sufficient to overcome the second spring acting on the second valve element in the closing direction. 
     
     
         19 . A valve arrangement comprising a flow path connecting an inlet and an outlet, a closing means arranged in said flow path, a resetting means and a first pressure in a first pressure chamber acting in a closing direction on said closing means, a pressure of said outlet and a second pressure in a second pressure chamber corresponding to a pressure of said inlet when said closing means is closed acting in an opening direction on said closing means, said first pressure chamber being connectable to the outlet via an auxiliary valve, wherein the closing means has a first opening state and a second opening state, a flow resistance of said closing means in said first opening state being larger than a flow resistance of said closing means in said second opening state, wherein said first pressure chamber is connected with said outlet via a second orifice, and said second valve element together with a second valve seat are forming a second valve means arranged parallel to said second orifice. 
     
     
         20 . The valve arrangement according to  claim 19 , wherein said second valve element is actuatable by a pressure at said outlet.