A mass-flow throttle for highly accurate control of the gaseous supplies (fuel and/or air) to the combustion chambers for a large engine in response to instantaneous demand signals from the engine's ECM, especially for large (i.e., 30 liters or greater in size) spark-ignited internal combustion engines fueled by natural gas. With a unitary block assembly and a throttle blade driven by a non-articulated rotary actuator shaft, in combination with tight control circuitry including multiple pressure sensors as well as sensors for temperature and throttle position, the same basic throttle concepts are innovatively suited to be used for both MFG and MFA throttles in industrial applications, to achieve highly accurate mass-flow control even despite pressure fluctuations while operating in non-choked flow.

A throttle valve device includes a shaft in a cylindrical passage, a slit passing through the shaft from one lateral side to another lateral side of the shaft, a pair of bearings on both sides of the cylindrical passage and rotatably supporting one end part and another end part of the shaft, and a circular-plate valve inserted into the slit of the shaft and rotatable to open and close the cylindrical passage. A length of the slit on the one lateral side of the shaft is, in an axial direction of the shaft, longer than a length of the slit on the other lateral side of the shaft. A round end hole is formed at an end of the slit in the one end part of the shaft on the one lateral side of the shaft.

A valve device for a fuel cell arrangement in a motor vehicle includes: a housing; a flow channel extending in the housing; a flap configured to influence a flow cross-section in the flow channel; a shaft to which the flap is attached, the shaft being rotatably supported in the housing; a drive configured to drive the flap via the shaft; a valve seat arranged in the flow channel; and a seal including polytetrafluoroethylene (PTFE) arranged on a radially peripheral edge of the flap, the seal being configured to contact the valve seat with the flap In a closed position of the flap, so that the shaft passes through the flap at an angle. The seal includes a spring.

A flap device for an internal combustion engine or an electric vehicle includes a flap body comprising a receiving opening, a duct housing configured to rotate arranged in the flap body, an actuator, a first bearing, a stub shaft arranged to project from the actuator through the duct housing to the flap body, a slide bearing arranged in the receiving opening of the flap body, and an axial pin arranged so as to be fixed in the duct housing on a side of the flap body opposite to the stub shaft. The stub shaft is supported in the duct housing via the first bearing. The axial pin supports the flap body via the slide bearing and projects into the receiving opening.

An intake duct that includes a first flange projecting outward from an edge of the intake duct on a throttle body side. An intake manifold that includes a second flange projecting outward from an edge of the intake manifold on a throttle body side. A plurality of spacers is provided between the first flange and the second flange around the throttle body. The first flange and the second flange are fastened via the plurality of spacers in a state where the throttle body is held between the intake duct and the intake manifold.

A transmission mechanism includes: an intermediate shaft secured to a support portion provided in a valve body of an electric throttle valve and disposed in parallel to a motor shaft and a valve shaft; and an intermediate gear rotatably disposed at the intermediate shaft, in which the intermediate gear has a first intermediate gear engaged with a motor gear secured to the motor shaft and a second intermediate gear engaged with a valve gear secured to the valve shaft, the first intermediate gear and the second intermediate gear are integrally configured to be aligned in an axial direction of the intermediate shaft, a hemispherical recessed portion recessed upward around an axial center of the intermediate shaft is formed at a lower end portion of the intermediate gear, and a projecting portion projecting upward in a hemispherical shape around the axial center of the intermediate shaft and supporting the recessed portion is formed in a surface of the support portion facing the recessed portion of the intermediate gear.

An intake duct that includes a first flange projecting outward from an edge of the intake duct on a throttle body side. An intake manifold that includes a second flange projecting outward from an edge of the intake manifold on a throttle body side. A plurality of spacers is provided between the first flange and the second flange around the throttle body. The first flange and the second flange are fastened via the plurality of spacers in a state where the throttle body is held between the intake duct and the intake manifold.

A valve comprises a coupling device having a driven member bound to the drive shaft of a flap, a driving member bound to an output shaft of an actuator, and an elastic member. The driving member comprises attachments that hooks up the elastic member to the driving member in a temporary position in which the elastic member is elastically loaded. The driven member comprises at least one release member that at least partly releases the elastic member of the attachments when the coupling device is brought to an intermediate state or the elastic member, when the coupling device is in the intermediate state, may be at least partly released from the attachments. The elastic member once released, adopts a definitive use position under the effect of relaxation of the elastic load, the coupling device then adopting the operational state.

An intake port is configured such that a center position of an intake upstream side opening is offset to one side in a juxtaposition direction of intake downstream side openings with respect to a center position between the intake downstream side openings in the juxtaposition direction as viewed in plan of a cylinder head. An injector is configured such that a fuel injection center axial line is inclined to the other side in the juxtaposition direction with respect to a center axial line of the intake upstream side opening as viewed in plan of the cylinder head.

An engine including a motorized throttle valve that can implement mutually neighboring disposition of a throttle body and a cylinder head and can implement a good opening and closing responsibility thereof. A swelling portion is formed on a side wall of a valve chamber in such a manner so as to bite between those of throttle bodies which neighbor with each other in order to accept a protrusion of part of a valve system in a radial direction of first and second camshafts. An electric motor is disposed at one side of the group of the throttle bodies. A speed reduction mechanism, for transmitting output power of the electric motor to a valve shaft, is disposed between those throttle bodies, which neighbor with each other at a different location in the group of the throttle bodies, in a neighboring relationship with the valve chamber.