Abstract: A valve device includes a valve main body having a valve chamber, and inflow and outflow passages communicating with the valve chamber; an annular valve seat surrounding an opening from the inflow passage to the valve chamber; and a valve element moved to contact with and separate from the valve seat. One of the valve seat and the valve element includes a contact surface, and the other of the valve seat and the valve element includes an annular raised rib. The rib has at a top thereof an annular sealing part contacting the contact surface to provide sealing between the valve element and the valve seat. The sealing part includes an annular flat surface extending parallel to the contact surface, and two annular inclined surfaces provided adjacent to the flat surface on both sides and inclined to the flat surface to extend in a direction away from the contact surface.

Abstract: An electric actuator includes a housing, an electric driving unit, an selector member being rotatable about a rotation axis and moving in a direction of the rotation axis, a position holding member and detection object provided in the selector member, a detector, an engagement groove provided on a cooperation surface inside the housing, and a biasing member biasing the selector member in the direction of the rotation axis to make the position holding member approach the cooperation surface. The engagement groove is formed so that the detection object is positioned in one of a detectable area and an undetectable area when the position holding member is engaged with the engagement groove, and the detector is configured to switch between supply and cutoff of power to the electric driving unit in accordance with whether or not the detection object is detected.

Abstract: A pinch valve 1 comprises a tube body 3 made of an elastic material having a flow path formed inside, a pressing part 4, a rod member 6 attached to a front end of the pressing part 4, and a coupling part 35 provided on the outer surface of the tube body 3 and coupling the rod member 6 to the tube body 3 in a transverse arrangement with respect to the tube body 3, wherein pressing or releasing the tube body 3 by the pressing part 4 through the rod member 6 makes the tube body 3 deform and opens or closes the flow path.

Abstract: A pinch valve 1 comprises a tube body 3 made of an elastic material having a cylindrically shaped tube main body 31 and annular flange parts 32 provided on the two ends of the tube main body 31 and having a flow path formed inside and a holding member 20 formed as a single piece and able to accommodate the tube body 3, wherein at least one of the flange parts 32 protrudes radially outward at an end part of the tube main body 31 via a curved part 33, at the curved part 33, a first curved surface part 33ais provided at the outside of the tube body 3 and a second curved surface part 33bis provided at the inside of the tube body 3, and in a cross section taken along a center axis of the tube body, a largest radius of curvature R1 is formed smaller than the largest curvature of radius R2 at the second curved part 33b.

Abstract: A diaphragm valve includes: a valve main body having formed therein a valve chamber, and an inflow passage and an outflow passage being in communication with the valve chamber; an annular valve seat formed in the valve chamber; a diaphragm contacting and separating from the valve seat; and a drive unit driving the diaphragm. The drive unit has a drive unit housing attached to the valve main body so that an outer peripheral edge portion of the diaphragm is sandwiched between the valve main body and the drive unit housing, and the drive unit housing is formed of an electroconductive fluorine resin material.

Abstract: In this butterfly valve (10) provided with: a main body (11); valve shafts (13, 14); and a valve body (30) that is rotatable with respect to the main body, the valve body is formed integrally from a core material (32) and a contour forming member (31) that is formed from a synthetic resin material and that encircles the core material and forms the contour of the valve body. The valve body has bearing holes (33, 34) that support the valve shafts, the contour forming member has a bearing inner peripheral part (36) that forms at least a part of the inner peripheral surface of each of the bearing holes, the contour forming member is formed continuously with the bearing inner peripheral part, and the core material has a bearing reinforcing part (35) that supports the bearing inner peripheral part of the contour forming member, radially outside from the rotation axis of the valve body.

Abstract: A diaphragm valve includes: a valve body having formed therein a first valve chamber, a second valve chamber and a communication passage communicating between the two valve chambers; a valve seat formed in the communication passage; a valve mechanism including a diaphragm supporting a valve element that comes in contact with and separates from the valve seat and a second diaphragm; a pressurizing unit being configured to pressurize the first diaphragm so as to press the valve element against the valve seat; and a bonnet for holding an outer peripheral part of the second diaphragm between the bonnet and the valve body. The pressurizing unit is configured as a single integrated unit holding therein a movable body that moves in conjunction with the valve element via a stem.

Abstract: Provided are: a mold material having improved fluidity and being capable of improving a filling rate of a forming mold during formation of a casting mold; and a mold material that gives cast products a favorable casting surface, effectively improves sand adhesion on cast products, and advantageously provides a casting mold having excellent strength. The mold material is formed as a coated sand in a wet state with spherical particles of silicone resin having binder repellency existing on its surface, by at least mixing a water-soluble inorganic binder in the liquid state having a viscosity of not more than 1000 cP, and the spherical particles of silicone resin, with a refractory aggregate.

Abstract: Provided are: a coated sand having improved fluidity and being capable of improving a filling rate of a casting mold to be obtained; and a coated sand for advantageously manufacturing a casting mold having excellent strength, which coated sand provides a casting mold with good mold-releasability and collapsibility, gives cast products a favorable casting surface, and effectively improves sand adhesion on cast products. The coated sand is formed as a dry granular material having fluidity at room temperature, in which the surface of a refractory aggregate is coated with a solid layer of a water-soluble inorganic binder, and spherical particles of silicone resin having binder-repellency exist on the surface of the binder layer, or form a layer on the surface of the binder layer, a part of the spherical particles being not covered with the water-soluble inorganic binder and being exposed.

Abstract: A butterfly valve includes a valve body with an internal flow passage extending in a direction of a flow passage axis, a disk-shaped valve member supported in the internal flow passage rotatably about a rotation axis perpendicular to the flow passage axis and having a spherical valve seat surface in an outer peripheral portion, an annular recessed portion surrounding the internal flow passage on the side surface of the valve body in a direction of the flow passage axis, and a seat ring attached to the annular recessed portion such that a valve seat portion provided in an inner peripheral edge portion thereof projects into the inner flow passage. The valve seat portion has a triangular cross section and is formed such that a bisector of a vertex angle in the triangular cross section of valve seat portion is perpendicular to a tangential line to the valve seat surface.

Abstract: A butterfly valve includes a valve body with an internal flow passage extending in a direction of a flow passage axis, a disk-shaped valve member supported in the internal flow passage rotatably about a rotation axis perpendicular to the flow passage axis and having a spherical valve seat surface in an outer peripheral portion, an annular recessed portion surrounding the internal flow passage on the side surface of the valve body in a direction of the flow passage axis, and a seat ring attached to the annular recessed portion such that a valve seat portion provided in an inner peripheral edge portion thereof projects into the inner flow passage. The valve seat portion has a triangular cross section and is formed such that a bisector of a vertex angle in the triangular cross section of valve seat portion is perpendicular to a tangential line to the valve seat surface.

Abstract: Provided is a butterfly valve pipe alignment mechanism configured so that favorable usability can be provided and an alignment process in plumbing can be easily performed. In the present invention, a groove (10) into which a positioning tool (11) is to be inserted is provided at a portion below a top flange (6). An end surface position of the groove (10) is on a plane on which a pipe flange (7) and a valve box (1) are joined to each other. The groove (10) is drilled in an elongated oval shape, and groove step portions (10a, 10b, 10c) projecting in both directions of a lateral direction are formed at multiple positions of the groove (10) so that the groove (10) can accept various flange connection standards.

Abstract: An eccentric butterfly valve includes a valve body formed therein with an internal flow passage extending in a direction of the flow passage axis, a disk-shaped valve member disposed in the internal flow passage and supported by the valve body through valve stems to be rotatable about a rotation axis R, and an annular valve seat portion provided on an inner periphery of the internal flow passage, and the internal flow passage is opened and closed by rotating the valve stem to bring a sealing surface of an outer peripheral edge portion of the valve member into and out of contact with the valve seat portion. The valve member is further provided in one of the principal surfaces with a groove portion extending in a direction across the rotation axis R, and both side walls of the groove portion are formed as convex curved surfaces extending in a convex shape.

Abstract: A pinch valve free of outflow of fluid at the inside of a tubing to the outside of the pinch valve even if the tubing ruptures. The pinch valve 1 comprises a valve part 2, a tubing 3 inside of which a flow path is formed and accommodated in the valve part 2, a pressing part 4 pressing the tubing 3 or releasing the pressing to cause the tubing 3 to deform and open and close the flow path, and a drive part 5 driving the pressing part 4, the pinch valve further comprising a seal part sealing a fluid connection between a space near an outside surface of the tubing 3 and an outside of the pinch valve 1.