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 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: 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: 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: 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 valve member supported by the valve body through valve stems to be rotatable about a rotation axis perpendicular to the flow passage axis, and a seat ring attached to an inner periphery of the internal flow passage. The valve stems include a first valve stem and a second valve stem. The valve body is formed therein with a stem through-hole through which the first valve stem is inserted and a stem bottomed-hole supporting the second valve stem. The valve member is provided with a fitting hole and an engagement groove. A fitting portion provided at the first valve stem is fitted into the fitting hole and an engagement portion provided at the second valve stem is inserted into the engagement groove.

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 valve member supported by the valve body through valve stems to be rotatable about a rotation axis perpendicular to the flow passage axis, and a seat ring attached to an inner periphery of the internal flow passage. The valve stems include a first valve stem and a second valve stem. The valve body is formed therein with a stem through-hole through which the first valve stem is inserted and a stem bottomed-hole supporting the second valve stem. The valve member is provided with a fitting hole and an engagement groove. A fitting portion provided at the first valve stem is fitted into the fitting hole and an engagement portion provided at the second valve stem is inserted into the engagement groove.

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 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: An ultrasonic flowmeter includes two ultrasonic transceivers. Each of the ultrasonic transceivers includes a cylindrical transmitting body closely fixed to the outer peripheral surface of a measurement pipe through a fluid flows so as to surround the measurement pipe, and an ultrasonic transducer surrounding the measurement pipe and spaced apart from the outer peripheral surface of the measurement pipe. The transmitting body is made of a rubber material and has axial end surfaces extending perpendicular to the axis of the measurement pipe. The axial end surface of the ultrasonic transducer is fixedly secured to the axial end surface of the transmitting body, and the ultrasonic transducer is extended and contracted in the axial direction thereof by applying a voltage between the axial end surfaces of the ultrasonic transducer.

Abstract: A fluid mixer is provided which can supply a fixed amount of fluid in each of supply lines to a mixing line all the time while maintaining a highly accurate mixing ratio even if a pressure on the downstream side of a back pressure valve of the mixing line is fluctuated and moreover can change the mixing ratio of the fluids in the supply lines with high accuracy in the state where the fluids are flowed. On the upstream side from a merging point where at least two supply lines: a first supply line and a second supply line are merged to a mixing line, diaphragm parts for adjusting the flow rates of the fluids and pressure reducing valves are arranged on the further upstream side of the diaphragm parts in series with the supply lines and a back pressure valve is arranged in the mixing line.

Abstract: The fluid control system according to the present invention is characterized by being provided with a fluid control valve controlling a pressure of a fluid by a pressure operation of a control fluid, a flow rate measuring device measuring a flow rate of the fluid, converting a measurement value of said flow rate to an electrical signal, and outputting it, and a control part outputting a command signal for controlling an opening area of said fluid control valve to said fluid control valve or equipment operating said fluid control valve based on a difference of said electrical signal from said flow rate measuring device and a set flow rate.

Abstract: An ultrasonic flowmeter includes two ultrasonic transceivers. Each of the ultrasonic transceivers includes a cylindrical transmitting body closely fixed to the outer peripheral surface of a measurement pipe through a fluid flows so as to surround the measurement pipe, and an ultrasonic transducer surrounding the measurement pipe and spaced apart from the outer peripheral surface of the measurement pipe. The transmitting body is made of a rubber material and has axial end surfaces extending perpendicular to the axis of the measurement pipe. The axial end surface of the ultrasonic transducer is fixedly secured to the axial end surface of the transmitting body, and the ultrasonic transducer is extended and contracted in the axial direction thereof by applying a voltage between the axial end surfaces of the ultrasonic transducer.

Abstract: An ultrasonic flowmeter includes two ultrasonic transceivers (10, 16). Each of the ultrasonic transceiver (10, 16) includes a transmitting body (1; 12) fixed to the outer peripheral surface of a measurement pipe (6) through which a fluid to be measured flows so as to surround the measurement pipe (6), and an ultrasonic transducer (2; 13) spaced from the outer peripheral surface of the measurement pipe (6). The transmitting body (1) has axial end surfaces (8a, 8b) perpendicular to the axis of the measurement pipe (6). An axial end surface (7) of the ultrasonic transducer (2) is fixedly secured to the axial end surface (8b) of the transmitting body (1), and the ultrasonic transducer (2) is extended and contracted in the axial direction by applying a voltage between the axial end surfaces (8a, 8b) of the ultrasonic transducer (2).

Abstract: An ultrasonic flowmeter includes two ultrasonic transceivers (10, 16). Each of the ultrasonic transceiver (10, 16) includes a transmitting body (1; 12) fixed to the outer peripheral surface of a measurement pipe (6) through which a fluid to be measured flows so as to surround the measurement pipe (6), and an ultrasonic transducer (2; 13) spaced from the outer peripheral surface of the measurement pipe (6). The transmitting body (1) has axial end surfaces (8a, 8b) perpendicular to the axis of the measurement pipe (6). An axial end surface (7) of the ultrasonic transducer (2) is fixedly secured to the axial end surface (8b) of the transmitting body (1), and the ultrasonic transducer (2) is extended and contracted in the axial direction by applying a voltage between the axial end surfaces (8a, 8b) of the ultrasonic transducer (2).

Abstract: A fluid mixer is provided which can supply a fixed amount of fluid in each of supply lines to a mixing line all the time while maintaining a highly accurate mixing ratio even if a pressure on the downstream side of a back pressure valve of the mixing line is fluctuated and moreover can change the mixing ratio of the fluids in the supply lines with high accuracy in the state where the fluids are flowed. On the upstream side from a merging point where at least two supply lines: a first supply line and a second supply line are merged to a mixing line, diaphragm parts for adjusting the flow rates of the fluids and pressure reducing valves are arranged on the further upstream side of the diaphragm parts in series with the supply lines and a back pressure valve is arranged in the mixing line.

Abstract: An electronic sphygmomanometer of simplified construction. Systolic and diastolic blood pressure are both indicated by the flashing of a light emission diode on receiving the Korotkov sound signals. A filtering circuit for passing Korotkov sound signals and eliminating pulse sound signals and other noise is used which has a passband with a low cutoff frequency of approximately 40 Hz with a sharp slope and high cutoff frequency of approximately 90 Hz with a gradual slope.