Control valve assembly for a gas passageway

Claim 2

A control valve assembly for exhausts mounted in a passageway for exhausts for controlling a stream of exhausts moving through said passageway comprising a valve body disposed in a horizontal plane in which an opening of an up stream portion of said passageway for exhausts and an opening of a downstream portion thereof are disposed, said valve body being adapted to move vertically relative to said horizontal plane to open and close communication between the two openings, a plurality of diaphragm chambers each having a diaphragm of the same area of a pressure receiving surface, said diaphragms being disposed opposite each other with respect to said horizontal plane, a spring mounted in one portion of one of said diaphragm chambers for urging said valve body by its biasing force to move into engagement with said openings of said upstream and downstream portions of said passageway for exhausts to interrupt the movement of exhausts through said passageway, said one portion of said one diaphragm chamber in which said spring is mounted being connected to a negative pressure source, the other portion of said one diaphragm chamber and a portion of the other diaphragm chamber which are interposed between the two diaphragms each being maintained in communication with the downstream portion of said passageway for exhausts, and the other portion of said other diaphragm chamber being maintained in communication with atmosphere.

Claim 3

A control valve assembly for a passageway for gases comprising: a casing (30) having a gas inlet duct (16) and a gas outlet duct (17), said casing (30) having openings (18) and (19) provided in a central portion thereof for said gas inlet and outlet ducts (16) and (17); a valve body (20) for simultaneously closing and opening said openings (18) and (19), said valve body (20) being supported on top of a stem (25) for movement in a direction normal to the plane of the openings (18) and (19); a first diaphragm mechanism provided in an upper portion of said casing (30), said first diaphragm mechanism including a first upper cover (21), a first lower cover (22), a first diaphragm (23) and a first support plate (24) provided in a central portion of said first diaphragm (23), said first support plate (24) being secured to one end of said stem (25); a first diaphragm chamber (26) defined by said first upper cover (21) and said first diaphragm (23); a negative pressure inlet duct (27) provided so as to communicate said first upper cover (21) to a negative pressure source; a spring (28) provided between an upper portion of said first diaphragm chamber (26) and said support plate (24), saId spring always urging the valve body (20) toward said openings (18) and (19); a second diaphragm chamber (29) defined by said first lower cover (22) and said first diaphragm (23), said casing (30) having a first port (31) to provide communication between said second diaphragm chamber (29) and said gas outlet duct (17); a second diaphragm mechanism provided in a lower portion of said casing (30), said second diaphragm mechanism including a second lower cover (32), a second upper cover (33), a second diaphragm (34) and a second support plate (35) provided in a central portion of said second diaphragm (34), said second support plate (35) being secured to the other end of said stem (25); a third diaphragm chamber (36) defined by said second lower cover (32) and said second diaphragm (34), said second lower cover (32) having a second port (37) communicating with atmosphere; and a fourth diaphragm chamber (38) defined by said second upper cover (33) and said second diaphragm (34), said casing (30) having a third port (39) communicating with said gas inlet duct (17).

Claim 4

A control valve assembly for a passageway for gases comprising: a casing (30) having a gas inlet duct (16) and a gas outlet duct (17), said casing (30) having openings (18) and (19) provided in a central portion thereof for said gas inlet and outlet ducts (16) and (17); a valve body (20) for simultaneously closing and opening said openings (18) and (19), said valve body (20) being supported on top of a stem (25) for movement in a direction normal to the plane of the openings (18) and (19); a first diaphragm mechanism provided in an upper portion of said casing (30), said first diaphragm mechanism including a first upper cover (21), a first lower cover (22), a first diaphragm (23) and a first support plate (24) provided in a central portion of said first diaphragm (23), said first support plate (24) being secured to one end of said stem (25); a first diaphragm chamber (26) defined by said first upper cover (21) and said first diaphragm (23); a negative pressure inlet duct (27) provided so as to communicate said first upper cover (21) to a negative pressure source; a spring (28) provided between an upper portion of said first diaphragm chamber (26) and said support plate (24), saId spring always urging the valve body (20) toward said openings (18) and (19); a second diaphragm chamber (29) defined by said first lower cover (22) and said first diaphragm (23), said casing (30) having a first port (31) to provide communication between said second diaphragm chamber (29) and said gas outlet duct (17); a second diaphragm mechanism provided in a lower portion of said casing (30), said second diaphragm mechanism including a second lower cover (32), a second upper cover (33), a second diaphragm (34) and a second support plate (35) provided in a central portion of said second diaphragm (34), said second support plate (35) being secured to the other end of said stem (25); a third diaphragm chamber (36) defined by said second lower cover (32) and said second diaphragm (34), said second lower cover (32) having a second port (37) communicating with atmosphere; and a fourth diaphragm chamber (38) defined by said second upper cover (33) and said second diaphragm (34), said casing (30) having a third port (39) communicating with said gas inlet duct (17).