Needle valve
AssigneeDaimlerChrysler AG
InventorsRoland Casar, Jan Gartner, Frank Obrist, Jurgen Wertenbach
Life of this patent
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Abstract
In a needle valve (1) for a high-pressure gas conduit system consisting of two units (2, 3) which are joined and one of which encloses a stepping motor (8) and the other includes gas flow passages and a gas flow control bore (17), a valve needle (10) is supported in the housing unit which includes the stepping motor so as to be movable by the stepping motor and extends into the gas flow control bore (17) in the other housing unit through a guide passage (18) provided with sealing means to prevent gas from flowing to the housing unit including the stepping motor (18). The needle valve is particularly suitable as an expansion valve in an automotive CO2 air conditioning system.
Claims19
A needle valve for a high-pressure gas conduit system, including a motor housing (3), 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) supported in said motor housing (3) 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 (4), 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 needle to said motor housing (3), said motor housing (3) being sealed to said valve housing (4).
Dependencies are inferred from the claim text.