A multifunction valve includes a valve body defining an inlet, and outlet and an interior chamber. A flow control gate is disposed within the interior chamber and is rotatable through an arcuate range of positions relative to the outlet providing a high level of precision control of a fluid flow rate through the multifunction valve. A method of modulating a fluid flow rate includes directing fluid flow through a multifunction valve from an inlet to an outlet, the multifunction valve including a flow control gate, adjusting the flow rate through the multifunction valve by rotating a control shaft to position the flow control gate to variably occlude the outlet of the fluid control valve.

A switching device includes a rod, a rotating shaft, and a valve assembly including a cover and a plug member. The cover engaged with the valve body has a first block section, a second block section, a space, and a threaded hole communicates with the space. The plug member is rotatably provided in a chamber of the cover, changing an area of an opening of an inlet hole. The rotating shaft has a projection is adapted to drive the plug member to rotate. A rod body of the rod has a threaded section engaged with the threaded hole. When the projection abuts against the first block section, the plug member seals the inlet hole. When the projection abuts against the rod, the plug member changes the area to a first area. When the projection abuts against the second block section, the plug member changes the area to a second area.

A valve assembly, includes a valve body having an inlet portion, an outlet portion, and a constriction portion; a shaft positioned within the valve body and extending along a longitudinal axis of the valve body; a cone provided within the inlet portion and configured to move along the shaft; a spring configured to bias the cone away from the constriction and positioned between a first piston fixed to the cone and a second piston fixed to the shaft; and an adjustable spacer positioned between a fixed position on the shaft and the second piston. The adjustable spacer is adjustable in length to change an effective length of the adjustable spacer and change a position of the second piston on the shaft.

A gas valve with two nozzles includes a valve body having an inlet, a primary outlet and a secondary outlet; a rotatable valve core is disposed inside the valve body; a valve rod inserted into the valve body; a first nozzle connected to a first outlet end of the primary outlet; and a second nozzle connected to a second outlet end of the secondary outlet; wherein, a connection chamber with a top opening for receiving the valve rod is mounted on the upper portion of the valve core; a ventilation chamber in communication with the primary outlet is defined in the lower portion of the valve core, the ventilation chamber having a side wall; a first high fire hole and a low fire hole both for communication between the inlet and the primary outlet are defined on the side wall of the ventilation chamber; and a second high fire hole for communication between the inlet and the primary outlet and a supplementary fire hole for communication between the ventilation chamber and the secondary outlet are defined on the side wall of the ventilation chamber of the valve core. In this gas valve, two nozzles can be kept in a gas injection state simultaneously only by rotating a valve rod to a certain position, without keeping a hand in a pressed-down operation position all the time.

Gas flow control valves comprising a valve housing including a cylindrical interior passage, and a housing opening extending from the interior passage through the housing. The gas flow control valve further comprises a cylindrical rotary valve element including a sidewall, and a rotary valve element opening extending through the sidewall. The valve element is rotatably received within the interior passage of the valve housing, such that the housing opening may be selectively aligned with the rotary valve element opening, and an area of overlap of the housing opening and the valve element opening may be varied by rotating the valve element within the interior passage of the valve housing.

A switching device includes a rod, a rotating shaft, and a valve assembly including a cover and a plug member. The cover engaged with the valve body has a first block section, a second block section, a space, and a threaded hole communicates with the space. The plug member is rotatably provided in a chamber of the cover, changing an area of an opening of an inlet hole. The rotating shaft has a projection is adapted to drive the plug member to rotate. A rod body of the rod has a threaded section engaged with the threaded hole. When the projection abuts against the first block section, the plug member seals the inlet hole. When the projection abuts against the rod, the plug member changes the area to a first area. When the projection abuts against the second block section, the plug member changes the area to a second area.

Gas flow control valves comprising a valve housing including a cylindrical interior passage, and a housing opening extending from the interior passage through the housing. The gas flow control valve further comprises a cylindrical rotary valve element including a sidewall, and a rotary valve element opening extending through the sidewall. The valve element is rotatably received within the interior passage of the valve housing, such that the housing opening may be selectively aligned with the rotary valve element opening, and an area of overlap of the housing opening and the valve element opening may be varied by rotating the valve element within the interior passage of the valve housing.

A flow control apparatus includes a pressure regulator fluidly coupled to an inlet region and an outlet region and configured to reduce a pressure from a first value in the inlet region to a second value in the outlet region, where the second value is lower than the first value; and a variable area orifice disposed between the outlet region and an outlet opening of the apparatus, wherein a flow rate of a gas is controlled by the variable area orifice and is discharged from the apparatus to a gas supply line. A free area of the variable area orifice that is disposed between a movable element and a surface of the variable area orifice is configured to change linearly in response to a translation of the movable element relative to the surface.

A flow control apparatus includes an adjustable pressure regulator fluidly coupled to an inlet region and an outlet region and configured to reduce a pressure from a first value in the inlet region to a second value in the outlet region, where the second value is lower than the first value; and a fixed area orifice disposed between the outlet region and an outlet opening of the apparatus, wherein a flow rate of a gas is controlled by the fixed area orifice and is discharged from the apparatus to a gas supply line. The second value is based on a setting of the adjustable pressure regulator.

Regulating valve for a gas cooking appliance suitable for supplying different types of combustible gas such as, for example, natural gas or liquefied gas. A valve body of the valve has an inlet conduit, an outlet conduit and a cavity wherein a rotary regulating member is housed. The regulating member includes a plurality of inlet paths communicated with the inlet conduit which, by means of the rotation of the regulating member, allows varying gas flow in the outlet conduit. According to some implementations, the inlet path of the regulating member corresponding to a minimum gas flow is in one and the same angular and axial position for each of the different types of combustible gases.