A valve includes a first plate (10) having a first through hole (100), a second plate (20) having a second through hole (210) that does not face the first through hole (100), a valve chamber (55) formed by being surrounded by the first plate (10) and the second plate (20), and a valve body (30) disposed in the valve chamber (55) and having a third through hole (300) that does not face the first through hole (100) and that faces the second through hole (200), the valve body (30) being movable up and down between the first plate (10) and the second plate (20). In addition, a second opening area of the second through hole (210) is smaller than a third opening area of the third through hole (300), and the second through hole (210) is located in the third through hole (300) when viewed from a front.

A valve includes a first plate (10) having a first through hole (100), a second plate (20) having a second through hole (210) that does not face the first through hole (100), a valve chamber (55) formed by being surrounded by the first plate (10) and the second plate (20), and a valve body (30) disposed in the valve chamber (55) and having a third through hole (300) that does not face the first through hole (100) and that faces the second through hole (200), the valve body (30) being movable up and down between the first plate (10) and the second plate (20). In addition, a second opening area of the second through hole (210) is smaller than a third opening area of the third through hole (300), and the second through hole (210) is located in the third through hole (300) when viewed from a front.

A purge control solenoid valve may include a middle housing in which an inlet flow path is formed and a middle flow path is formed on a center; a valve housing in which a driving module selectively communicating the inlet flow path and the middle flow path is installed; an upper cover coupled to the upper part of the middle housing and including a upper flow path selectively communicated with the middle flow path on the center; and a membrane provided on the upper cover and selectively communicating the middle flow path and the upper flow path.

A purge control solenoid valve may include a middle housing in which an inlet flow path is formed and a middle flow path is formed on a center; a valve housing in which a driving module selectively communicating the inlet flow path and the middle flow path is installed; an upper cover coupled to the upper part of the middle housing and including a upper flow path selectively communicated with the middle flow path on the center; and a membrane provided on the upper cover and selectively communicating the middle flow path and the upper flow path.

A valve body has a piston that slides within the body through four successive positions. The piston has a head, and an upper and lower skirt, with a port in the upper skirt. In the first position, a bias force urges the piston to the first of four positions, in which the piston port is closed. In a second position, the piston port aligns with a low pressure port in the valve body, when a low pressure supply of water is connected. In a third position, greater pressure again closes the piston port. In a fourth position, at a still greater pressure, the piston port aligns with a high pressure port in the valve body. The bias force or a location of the piston port can be varied for valves along a supply line, whereby varying supply pressure opens different valves, thereby enabling addressing of valves according to supply pressure.

A valve body has a piston that slides within the body through four successive positions. The piston has a head, and an upper and lower skirt, with a port in the upper skirt. In the first position, a bias force urges the piston to the first of four positions, in which the piston port is closed. In a second position, the piston port aligns with a low pressure port in the valve body, when a low pressure supply of water is connected. In a third position, greater pressure again closes the piston port. In a fourth position, at a still greater pressure, the piston port aligns with a high pressure port in the valve body. The bias force or a location of the piston port can be varied for valves along a supply line, whereby varying supply pressure opens different valves, thereby enabling addressing of valves according to supply pressure.

The invention relates to a mechanical valve assembly used in the control of a fluid (e.g. gas, liquid, etc.) to provide at least one of a check valve control feature and flow range control feature. When unwanted low flows are present, the valve remains closed and jumps open only at higher desired flow rates. The valve then closes when the forces at the input and output equalize and the process repeats. Such allows fluid delivered to a flow meter in larger segregated bursts, rather than steady low flows that cause metering error.

A valve includes a first plate (10) having a first through hole (100), a second plate (20) having a second through hole (210) that does not face the first through hole (100), a valve chamber (55) formed by being surrounded by the first plate (10) and the second plate (20), and a valve body (30) disposed in the valve chamber (55) and having a third through hole (300) that does not face the first through hole (100) and that faces the second through hole (200), the valve body (30) being movable up and down between the first plate (10) and the second plate (20). In addition, a second opening area of the second through hole (210) is smaller than a third opening area of the third through hole (300), and the second through hole (210) is located in the third through hole (300) when viewed from a front.

A purge control solenoid valve may include a middle housing in which an inlet flow path is formed and a middle flow path is formed on a center; a valve housing in which a driving module selectively communicating the inlet flow path and the middle flow path is installed; an upper cover coupled to the upper part of the middle housing and including a upper flow path selectively communicated with the middle flow path on the center; and a membrane provided on the upper cover and selectively communicating the middle flow path and the upper flow path.

A valve includes a first plate, a side wall plate, a second plate, and a third plate. The first plate has a plurality of first vent holes. The second plate constitutes a valve chamber along with the first plate and the side wall plate. The second plate includes a second principal surface opposing a first principal surface of the first plate. The second plate has a plurality of second vent holes. The third plate has a plurality of third vent holes. The plurality of third vent holes overlaps with the plurality of first vent holes without overlapping with the plurality of second vent holes in a plan view in a direction in which the first plate and the second plate oppose each other. Both principal surfaces of the third plate oppose the first principal surface and the second principal surface. The third plate is disposed in the valve chamber.