A valve actuator includes moving equipment arranged to cause a plug of said equipment to slide along a given axis between two end positions. The moving equipment includes a core constrained to move in translation with the plug along the given axis. The actuator also includes a coil lying between two rings of ferromagnetic material, all three of which are secured to a frame of the actuator so as to surround the core, which itself carries two magnets mounted in opposition on the core level with the coil, a ring of ferromagnetic material lying between the two magnets that also lie between two other rings of ferromagnetic material. A valve and a machine may be fitted with such an actuator.

The present invention discloses a movable valve core and an electromagnetic valve comprising the same. The movable valve core, comprising a cylindrical core body (1) defining a central axis, a leading head (2) fixed to the core body (1) removably, wherein a water-proof valve membrane (3) sandwiched between the core body (1) and the leading head (2), wherein a mounting hole (4) is axially formed in the core body (1), and a connector (5) for projecting into the mounting hole (4) extends axially from the bottom of the leading head (2), and the connector (5) is fixed into the mounting hole (4). The connector (5) is provided with an outer thread (6), and the leading head (2) is screwed into the mounting hole (4).

A pilot valve system is controlled by the pressure differential between a lower chamber and an upper chamber. A fluid passageway in the lower chamber fluidly connects an inlet to first and second outlets. By varying the pressure differential, the placement of a stem within the fluid passageway is varied so fluid can flow between the inlet and only one of the first and second outlets at a time. Pressure in the lower chamber can be varied by using a second fluid to exert pressure against a bottom end of the stem. Pressure in the upper chamber is varied by using an adjusting screw to urge a spring against the diaphragm.

Provided is a switching valve for use in an analyzer module for switching flow passages of fluids, in which the manufacturing cost is reduced and the life is increased. The valve element is provided with a lower contact portion that comes into close contact with a lower valve seat disposed at a valve body when a valve is closed, and with an upper contact portion that comes into close contact with an upper valve seat disposed at a counter plate when the valve is open. The counter plate has a first recess that is open downward and a second recess that is open toward the first recess and has a smaller horizontal cross-sectional area than that of the first recess, and the upper valve seat is press-fitted into the second recess.

A valve element movement mechanism includes: a first valve stem having one end portion to which a first valve element to close and open an area between one of the large diameter portion and the small diameter portion is fixed; a second valve stem having one end portion to which a second valve element to close and open an area between the other of the large diameter portions and the small diameter portion is fixed; a first bellows having one end portion fixed to a first bellows flange and the other end portion fixed to the first valve element; a second bellows having one end portion fixed to a second bellows flange and the other end portion fixed to the second valve element; a frame disposed outside the main passage; and an actuator to move the frame in the directions in which valve elements are closed and opened.

The present invention discloses a movable valve core and an electromagnetic valve comprising the same. The movable valve core, comprising a cylindrical core body (1) defining a central axis, a leading head (2) fixed to the core body (1) removably, wherein a water-proof valve membrane (3) sandwiched between the core body (1) and the leading head (2), wherein a mounting hole (4) is axially formed in the core body (1), and a connector (5) for projecting into the mounting hole (4) extends axially from the bottom of the leading head (2), and the connector (5) is fixed into the mounting hole (4). The connector (5) is provided with an outer thread (6), and the leading head (2) is screwed into the mounting hole (4).

A valve assembly includes an upper sleeve, a lower sleeve, and a poppet contained between the upper and lower sleeve and operable between a first and second position. The poppet includes a first end, a second end, a side, a central cavity, and a hydraulic port. The second end is spaced from the first end, the side is adjacent one of the first end and the second end. The central cavity extends from the first end of the poppet towards the second end of the poppet. The hydraulic port extends from the side of the poppet into the central cavity. The hydraulic port is configured to receive hydraulic fluid at a first flow rate from the supply port and to supply hydraulic fluid to the central cavity at a second flow rate less than the first flow rate.

A valve actuator includes moving equipment arranged to cause a plug of said equipment to slide along a given axis between two end positions. The moving equipment includes a core constrained to move in translation with the plug along the given axis. The actuator also includes a coil lying between two rings of ferromagnetic material, all three of which are secured to a frame of the actuator so as to surround the core, which itself carries two magnets mounted in opposition on the core level with the coil, a ring of ferromagnetic material lying between the two magnets that also lie between two other rings of ferromagnetic material. A valve and a machine may be fitted with such an actuator.

Provided is a switching valve for use in an analyzer module for switching flow passages of fluids, in which the manufacturing cost is reduced and the life is increased. The valve element is provided with a lower contact portion that comes into close contact with a lower valve seat disposed at a valve body when a valve is closed, and with an upper contact portion that comes into close contact with an upper valve seat disposed at a counter plate when the valve is open. The counter plate has a first recess that is open downward and a second recess that is open toward the first recess and has a smaller horizontal cross-sectional area than that of the first recess, and the upper valve seat is press-fitted into the second recess.

A valve element movement mechanism includes: a first valve stem having one end portion to which a first valve element to close and open an area between one of the large diameter portion and the small diameter portion is fixed; a second valve stem having one end portion to which a second valve element to close and open an area between the other of the large diameter portions and the small diameter portion is fixed; a first bellows having one end portion fixed to a first bellows flange and the other end portion fixed to the first valve element; a second bellows having one end portion fixed to a second bellows flange and the other end portion fixed to the second valve element; a frame disposed outside the main passage; and an actuator to move the frame in the directions in which valve elements are closed and opened.