Abstract: A portion of the one valve rod which extends outward is pivotally supported, the valve shaft cylindrical portion which is connected to the valve rod shaft supporting portion is made of material different from that of the valve body, a slanting surface is formed between the inner peripheral surface and the outer peripheral surface of the sheet ring, an angle and a width formed by the slanting surface and the outer peripheral side surface are the greatest at a position intersecting with the valve shaft at right angles and are the smallest at a position of the valve shaft, a central portion of an inner peripheral surface of the valve body is allowed to project inward to form an engaging projection, the sheet ring is brought into contact with the inner peripheral surface of the valve body under pressure in the opposite sides of the recess groove, the cylindrical bush whose one end is closed is mounted to the other valve rod which pivotally supports the valve element, and the other valve rod is sealed.

Abstract: The purpose of this invention is to provide an actuator for valve driving without enlarging its size, without increasing the cost, and without reducing the pressure receiving area of the pistons.

Abstract: A portion of the one valve rod which extends outward is pivotally supported, the valve shaft cylindrical portion which is connected to the valve rod shaft supporting portion is made of material different from that of the valve body, a slanting surface is formed between the inner peripheral surface and the outer peripheral surface of the sheet ring, an angle and a width formed by the slanting surface and the outer peripheral side surface are the greatest at a position intersecting with the valve shaft at right angles and are the smallest at a position of the valve shaft, a central portion of an inner peripheral surface of the valve body is allowed to project inward to form an engaging projection, the sheet ring is brought into contact with the inner peripheral surface of the valve body under pressure in the opposite sides of the recess groove, the cylindrical bush whose one end is closed is mounted to the other valve rod which pivotally supports the valve element, and the other valve rod is sealed.

Abstract: A simplified butterfly valve with low noise in which a cavitation to be generated in a narrowed flow region that is delimited by a valve disc in a valve casing is reduced thereby to control the noise, and the valve can be applied even to a flow line for a fluid containing slurry or foreign particles, and can be used for a fluid flow line through a fluid is flows at a high flow rate. In the butterfly valve with low noise, an enlarged section 35 having the enlarged sectional shape symmetrical relative to the center axis is provided in a downstream side immediately behind a valve seat so as to control or suppress the noise and cavitation which occur around the valve disc, an inner diameter Dy of the enlarged section 35 is made more than 1.3 times a inner diameter D of the piping to which the valve is mounted, and the length X1 of the enlarged section 35 is made more than 0.5 times the inner diameter D of the piping.

Abstract: A manual device for a valve has: a movable valve opening member sustained rotatably and disposed in a valve body; an opening and closing of the valve for controlling the opening and closing oi a fluid passage; a notch plate connected with one end of a stem which is pivotably sustaining the valve; a notch plate moving freely in axial direction on the stem and which rotates synchronously with the stem; a manual and oprative knob adhered to the notch plate; a casing adhered to the valve body, so that the casing stores the notch plate and guides the movement of the notch plate freely in the axial direction and guides rotation of the notch plate; a notch means preventing the extra rotation of the notch plate by mutual engagement between the notch plate and the casing; and a notch plate which is constantly pressurized to keep the engagement.

Abstract: A seat ring is resiliently fitted into upper and lower main bodies of a butterfly valve divided in a horizontal direction of piping so as to prevent a fluid from being leaked from the butterfly valve.

Abstract: A butterfly valve is described, including: a valve body made from synthetic material and having an internal cylindrical fluid passage; a movable disk valve disposed in the valve body for controlling the opening and closing of the fluid passage; a seated ring made from elastic material inserted between the valve body and the disk valve for closing the fluid passage when the disk valve is in a closed position; a shaft hole formed in the valve body into which a stem is inserted; a shaft cylinder formed to extend outwardly from an outer circumference of the valve body in corresponding with the shaft hole, the stem being inserted into the shaft cylinder and holding the valve axially, the valve body being divided along at least one division line formed across the fluid passage and being composed of plural divided parts, each divided part being joined at a joining surface extending circumferentially to form one complete valve body and being produced with a plurality of cavity portions in order to achieve light weigh

Abstract: A butterfly valve having a function for measuring a flow rate of a fluid flowing through the butterfly valve includes a main body, a valve shaft fixed rotatably to the main body, a valve member fixed to the valve shaft and mounted rotatably in the main body, a valve opening detection device for detecting a valve opening of the butterfly valve, and a torque detection device for detecting a dynamic torque applied to the valve member around the valve shaft by the fluid.

Abstract: A butterfly valve is adapted to pivot a valve stem to a valve body through openings formed in a ring-shaped elastic valve seat attached inside the valve body, to slidably contact the valve member and the inner face of the valve seat each other in the vicinity of the valve stem, and to form recesses for charging lubricant in the slidably contacting face on the valve seat or on the side face of the valve member.

Abstract: A butterfly valve comprising a valve body, a disk-shaped valve member pivotally provided on the valve body, and a seat ring fixed to the valve body, the seat ring having a circumferential protrusion on an inner surface thereof.

Abstract: A driving device for opening and closing a valve comprises a cylindrical body, an actuating cylinder, a spindle, a piston member, a transparent plate and a stop means for controlling the rotation of the spindle. Said stop means comprises a ring gear, a spring and a stop bar having a wedge-shaped head, said wedge head having a pair of surfaces forming an included angle which is bisected by the axis of the stop bar such that rotation of the spindle by fluid pressure on the valve is prevented but manual rotation of the spindle in either direction is permitted.

Abstract: A reduction apparatus mainly comprises a casing mounted on a valve body, an input shaft, an external gear, an internal gear capable of engaging the external gear, a rotary member connected to the internal gear to transmit the torque from the same to a valve stem, and pin assemblies for preventing the external gear from rotating on its own shaft, while external gear revolves about the other shaft without rotating on its own axis, whereby the internal gear having a slightly larger number of teeth is given rotation due to the difference in number of teeth of both gears, and the rotation of the input shaft is transmitted to the valve stem with its speed reduced.

Abstract: A butterfly valve comprises a valve body, a valve seat, a valve stem, a valve member and sealing assemblies. The valve seat has three layers such as a first, a second and a third layers which are formed from hard synthetic resin, resilient material and fluororesin respectively. An effective seal can be achieved by providing an inwardly convex contour on the inner peripheral surface of the valve seat.

Abstract: A butterfly valve comprises a valve body, a valve seat, a valve stem, a valve member and sealing assemblies in which the central portion of a seat face of the valve seat is raised higher than both of its side portions and the diameter of the valve seat at the central raised portion is smaller than that of the valve member whereby a perfect seal can be achieved.

Abstract: A butterfly valve having a function for measuring a flow rate of a fluid flowing through the butterfly valve includes a main body, a valve shaft fixed rotatably to the main body, a valve member fixed to the valve shaft and mounted rotatably in the main body, a valve opening detection device for detecting a valve opening of the butterfly valve, and a torque detection device for detecting a dynamic torque applied to the valve member around the valve shaft by the fluid.