Abstract: A butterfly valve includes a purge gas flow path supplying a purge gas for preventing inflow of a control fluid into a magnetic fluid sealing portion from a flow path through an insertion hole. The purge gas flow path is provided with an opening and closing valve for opening and closing the purge gas flow path and a pressure gauge for measuring a pressure value in the purge gas flow path, in the stated order from the upstream side. The purge gas flow path is connected to a portion between the magnetic fluid sealing portion and the flow path of the butterfly valve on the downstream side of the pressure gauge, and communicates with the flow path through the insertion hole. The butterfly valve further includes a control device that controls at least the opening and closing valve. The control device is provided with a monitoring program for monitoring a pressure value.

Abstract: A sealing device that is adapted to be disposed between a reciprocating shaft and an inner peripheral surface of a shaft hole in which the reciprocating shaft is disposed, and that separates an oil side from an atmosphere side, includes an annular oil seal made of a resin, an oil-side rigid ring made of a metal, an elastomeric annular dust seal, and an atmospheric-side rigid ring made of a metal. The oil seal has an oil lip adapted to be in slidable contact with the reciprocating shaft and is formed of a resin having a glass transition temperature of 80 degrees Celsius or higher. The oil-side rigid ring is disposed around the oil seal and supports the oil seal. The dust seal is disposed on the atmosphere side of the oil seal and has a dust lip adapted to be in slidable contact with the reciprocating shaft.

Abstract: An elastic body includes an annular main body portion to be disposed in an annular gap, a seal lip portion extending from a portion, closer to an object to be sealed, of the main body portion and being to be in contact with an inner member, a flange portion extending outwardly from an end, opposite to the object to be sealed, of the main body portion and including a first side closer to the object to be sealed, the first side being to be in contact with an outer member, a side lip portion extending from the end opposite to the object to be sealed in a direction away from the object to be sealed, and a projecting portion formed circumferentially on a second side, opposite to the object to be sealed, of the flange portion. The side lip portion has a back surface configured to be in contact with the projecting portion in response to the side lip portion being pressed by a mating member disposed opposite to the object to be sealed.

Abstract: A sealing device that is adapted to be disposed between a reciprocating shaft and an inner peripheral surface of a shaft hole in which the reciprocating shaft is disposed, and that separates an oil side from an atmosphere side, includes an annular oil seal made of a resin, an oil-side rigid ring made of a metal, an elastomeric annular dust seal, and an atmospheric-side rigid ring made of a metal. The oil seal has an oil lip adapted to be in slidable contact with the reciprocating shaft and is formed of a resin having a glass transition temperature of 80 degrees Celsius or higher. The oil-side rigid ring is disposed around the oil seal and supports the oil seal. The dust seal is disposed on the atmosphere side of the oil seal and has a dust lip adapted to be in slidable contact with the reciprocating shaft.

Abstract: A sealing device seals a rod having a cylindrical part and a cylindrical guide that guides reciprocation of the rod in an axial direction of the rod. The sealing device includes an elastic ring formed of an elastic material, and a rigid ring formed of a rigid material fixed to the elastic ring for reinforcing the elastic ring. The elastic ring includes a lip with which an outer peripheral surface of the rod is in slidable contact. The rigid ring includes a rigid-ring cylindrical part located radially outside an end portion of the guide. The rigid-ring cylindrical part includes multiple hook hasps engaged into at least one recess formed on an outer peripheral surface of the guide. Each of the multiple hook hasps includes a root portion and a distal end portion located radially inward of the root portion and fitted into the recess. A thin portion is formed at the root portion of the hook hasp, the thin portion being thinner than other parts of the hook hasp.

Abstract: Provided is a sealing apparatus that can prevent a garter spring from falling off an elastic member. The sealing apparatus comprises a reinforcing ring formed annularly around an axis, an elastic body part that is attached to the reinforcing ring and that is formed annularly around the axis, and a garter spring attached to the elastic body part. The reinforcing ring includes a retainer that is an annular portion projecting to an outer periphery side from an end portion on one side of the reinforcing ring in a direction of the axis. The elastic body part has at least one projection that is formed on the one side of a zone to which the garter spring is attached in the direction of the axis and that projects from the elastic body part to the outer periphery side.

Abstract: A sealing device seals a rod having a cylindrical part and a cylindrical guide that guides reciprocation of the rod in an axial direction of the rod. The sealing device includes an elastic ring formed of an elastic material, and a rigid ring formed of a rigid material fixed to the elastic ring for reinforcing the elastic ring. The elastic ring includes a lip with which an outer peripheral surface of the rod is in slidable contact. The rigid ring includes a rigid-ring cylindrical part located radially outside an end portion of the guide. The rigid-ring cylindrical part includes multiple hook hasps engaged into at least one recess formed on an outer peripheral surface of the guide. Each of the multiple hook hasps includes a root portion and a distal end portion located radially inward of the root portion and fitted into the recess. A thin portion is formed at the root portion of the hook hasp, the thin portion being thinner than other parts of the hook hasp.

Abstract: A valve stem seal with significantly improved sealing performance while improving workability when fitting the valve stem seal to a valve stem guide. An inner peripheral surface of a fitting section 20B is provided with a plurality of annular seal protrusions which respectively include first inclined surfaces 25a and 26a each having a diameter that increases from a radially inward tip toward a seal section 20A side, and second inclined surfaces 25b and 26b each having a diameter that increases from a radially inward tip toward a side opposite to the seal section 20A. The first seal protrusion 25 which is closest to the seal section 20A is configured so that an inclination of the second inclined surface 25b is smaller than that of the first inclined surface 25a, and the second seal protrusion 26 which is farthest from the seal section 20A is configured so that an inclination of the first inclined surface 26a is smaller than that of the second inclined surface 26b.

Abstract: A flange portion in an annular shape extending toward the axis is formed at an end portion of a reinforcement ring on the cam side, and the flange portion is positioned between a seal lip and a back pressure lip of an elastic body part in the axis direction. An interval in the axis direction between an inner-periphery end portion of the flange portion and a root portion of the back pressure lip in the elastic body part is larger than an interval in the axis direction between the root portion of the back pressure lip and a tip end portion of the back pressure lip, and the outline of a cylinder-side corner portion of the inner-periphery end portion of the flange portion on the cylinder side is a curved line in a cross section.

Abstract: A valve stem seal with significantly improved sealing performance while improving workability when fitting the valve stem seal to a valve stem guide. An inner peripheral surface of a fitting section 20B is provided with a plurality of annular seal protrusions which respectively include first inclined surfaces 25a and 26a each having a diameter that increases from a radially inward tip toward a seal section 20A side, and second inclined surfaces 25b and 26b each having a diameter that increases from a radially inward tip toward a side opposite to the seal section 20A. The first seal protrusion 25 which is closest to the seal section 20A is configured so that an inclination of the second inclined surface 25b is smaller than that of the first inclined surface 25a, and the second seal protrusion 26 which is farthest from the seal section 20A is configured so that an inclination of the first inclined surface 26a is smaller than that of the second inclined surface 26b.

Abstract: A controller and a control method for a controller can simplify application development and can improve the performance of device control processes. When a request is received from an application 1 and the received process request is an initialization request, whether or not the received request is the first initialization request received after the application 1 started running is determined. If the received initialization request is the first initialization request, the request is passed to the device driver 3 and initialization settings information describing the configuration of the device driver 3 after the initialization process ends is stored. If an error has occurred in the device driver 3 when the device driver 3 status is detected, an error handling process is executed according to the device driver 3 state. When the device driver 3 has recovered, a request for setting the device driver 3 state to the state based on the initialization settings information is asserted.

Abstract: A part of a rubber layer of the base section of a piston seal is replaced with a reinforcement ring with high rigidity, and a part of the reinforcement ring reaches the root of a seal lip. This provides the piston seal with required rigidity. Further, providing an outer diameter side radial section on a piston body secures a contact width coming into contact with a section to be pressed. A piston has a piston body (111) having a clutch pressing section (111f) provided so as to be in surface-contact with a multiple disc clutch (105), a reinforcement ring (112) fitted on the outer periphery of an outer cylinder section (111e) of the piston body, and an outer peripheral seal lip (113a) provided on the reinforcement ring and in sealing contact with the inner peripheral surface (102a) of the outer peripheral section of a housing (102).