Patent ID: 6991212
Filing Date: 2006-01-31
Classification: F16K,F25B,Y02B

Abstract:
1. A needle valve for a high-pressure gas conduit system, including a motor housing ( 7 ), a valve housing ( 4 ) having connection bores ( 13 , 14 ) for receiving pipe portions ( 5 , 6 ) of the gas conduit system, a valve bore ( 17 ) extending between the connection bores ( 13 , 14 ) and a guide bore ( 18 , 32 ) coaxially formed in said valve housing ( 4 ) with said valve bore ( 17 ), a valve needle ( 10 ) with a cylindrical needle shaft part supported in said motor housing ( 7 ) and extending into said valve bore ( 17 ) in said valve housing ( 4 ) and connected to a stepping-motor drive ( 8 , 9 ) disposed in said motor housing ( 7 ), and sealing means ( 19 , 20 , 23 , 24 ) extending around said needle in the area of said guide bore ( 18 , 32 ) for preventing gas from flowing along said cylindrical needle shaft part to said motor housing ( 7 ), said motor housing ( 7 ) being sealed to said valve housing ( 4 ), and a compensation connection ( 42 ) extending between a region ( 41 ) of said guide bore ( 18 ) surrounding the valve needle ( 10 ) and a low pressure region ( 43 ) of the needle valve ( 1 ) for the relief of pressure at the sealing region of the guide bore ( 18 ), the region ( 41 ) being arranged between the at least one sealing means ( 23 – 26 ) and the adjacent valve conduit ( 15 ).