Abstract: A cover-equipped manual valve having a ratchet mechanism for preventing rotation of a knob, comprising: a rod formed with an external thread portion on an outer periphery thereof, the rod being unconnected to the knob and held against rotation; a sliding nut of a cylindrical shape, the sliding nut being rotatably held by a body and internally formed with an internal thread portion threadedly engaged with the external thread portion of the rod; an engagement member fixed to the knob, the engagement member being elastically deformable to be engaged with the sliding nut and to be disengaged from the sliding nut when larger torque than a predetermined value is applied to the engagement member; and a knob cover of a hollow shape for covering the knob.

Abstract: For providing a fluid control valve capable of preventing looseness of a screw part between a valve main body and a valve upper body, the fluid control valve comprises a resin valve main body wherein a valve seat comes into or out of contact with a diaphragm, and a resin valve upper body engaged with the valve main body. The fluid control valve comprises a holding member to keep the valve main body and the valve upper body threadedly screwed together.

Abstract: A manual valve comprises a valve element, a rod connected to the valve element, and a knob for moving the rod by screw feeding in an opening/closing direction with respect to the valve element. The valve element is moved by rotation of the knob through the rod. The rod includes an external thread portion on an outer periphery thereof and is not connected to the knob and is held against rotation. Further, the manual valve includes a cylindrical sliding nut rotatably held by a body and formed with an internal thread portion to be engaged with the external thread portion of the rod on its inner periphery and a clip fixed to the knob to be elastically deformably engaged with the sliding nut but disengaged when a larger torque than the predetermined value is applied.

Abstract: A cover-equipped manual valve having a ratchet mechanism for preventing rotation of a knob, comprising: a rod formed with an external thread portion on an outer periphery thereof, the rod being unconnected to the knob and held against rotation; a sliding nut of a cylindrical shape, the sliding nut being rotatably held by a body and internally formed with an internal thread portion threadedly engaged with the external thread portion of the rod; an engagement member fixed to the knob, the engagement member being elastically deformable to be engaged with the sliding nut and to be disengaged from the sliding nut when larger torque than a predetermined value is applied to the engagement member; and a knob cover of a hollow shape for covering the knob.

Abstract: A diaphragm valve having a diaphragm valve element including a valve element body movable into contact with a valve seat, a web portion extending outward from the valve element body, and a fixed portion formed at an outer peripheral edge of the web portion. The web portion includes a vertical portion vertically formed continuous with the valve element body, a horizontal portion horizontally formed continuous with the fixed portion, and a connecting portion of a circular arc shape (an upward protruding shape) in section to connect the vertical portion with the horizontal portion, thereby holding the vertical portion in constant contact with an outer surface of a backup.

Abstract: A manual valve comprises a valve element, a rod connected to the valve element, and a knob for moving the rod by screw feeding in an opening/closing direction with respect to the valve element. The valve element is moved by rotation of the knob through the rod. The rod includes an external thread portion on an outer periphery thereof and is not connected to the knob and is held against rotation. Further, the manual valve includes a cylindrical sliding nut rotatably held by a body and formed with an internal thread portion to be engaged with the external thread portion of the rod on its inner periphery and a clip fixed to the knob to be elastically deformably engaged with the sliding nut but disengaged when a larger torque than the predetermined value is applied.

Abstract: For providing a fluid control valve capable of preventing looseness of a screw part between a valve main body and a valve upper body, the fluid control valve comprises a resin valve main body wherein a valve seat comes into or out of contact with a diaphragm, and a resin valve upper body engaged with the valve main body. The fluid control valve comprises a holding member to keep the valve main body and the valve upper body threadedly screwed together.

Abstract: A chemical liquid valve is arranged such that a diaphragm coupled to a piston rod is brought into/out of contact with a valve seat provided between an inlet port and an outlet port. To achieve a chemical liquid valve providing stable sealing strength, the diaphragm includes an engagement part whose top end is formed in semispherical shape, which is inserted and engaged in a recess of the piston rod so that the engagement part of the diaphragm comes into point contact with an inner wall of the recess of the piston rod. Thus, the piston rod swingably holds the diaphragm.

Abstract: The present invention is made to prevent stress concentration on or around a boundary between a valve element body and a web portion of a diaphragm even in controlling supply of high-pressure fluid, thereby improving durability of the diaphragm. A diaphragm valve 1 of the present invention comprises a diaphragm valve element 20 including a valve element body 21 movable into contact with a valve seat 13, a web portion 22 extending outward from the valve element body 21, and a fixed portion 23 formed at an outer peripheral edge of the web portion 22. The web portion 22 includes a vertical portion 22a vertically formed continuous with the valve element body 21, a horizontal portion 22c horizontally formed continuous with the fixed portion 23, and a connecting portion 22b of a circular arc shape (an upward protruding shape) in section to connect the vertical portion 22a with the horizontal portion 22c, thereby holding the vertical portion 22a in constant contact with an outer surface of a backup 40.

Abstract: To provide a diaphragm valve 1 in which a diaphragm valve element 20 airtightly closes open ends on an upper surface of a body 10 to provide a valve-closed state when the diaphragm valve element 20 is pressed against a valve seat 13 by urging force of an urging member 33, and to provide a valve-open state when the diaphragm valve element 20 is separated from the valve seat 13. The diaphragm valve element 20 comprises a main body 21 in contact with the valve seat 13, a diaphragm part 22 extending outwards from the main body 21, and a fixed part 23 formed at a peripheral edge of the diaphragm part 22. A root 25 of the diaphragm part 22 formed in the main body 21 is positioned inside a diameter of the valve seat 13 and lower than the peripheral edge of the diaphragm part 22 which extends in a curve in a valve-closed state.

Abstract: A chemical liquid valve is arranged such that a diaphragm coupled to a piston rod is brought into/out of contact with a valve seat provided between an inlet port and an outlet port. To achieve a chemical liquid valve providing stable sealing strength, the diaphragm includes an engagement part whose top end is formed in semispherical shape, which is inserted and engaged in a recess of the piston rod so that the engagement part of the diaphragm comes into point contact with an inner wall of the recess of the piston rod. Thus, the piston rod swingably holds the diaphragm.