Abstract: A structure and method for fastening a ball seat for a ball valve, a trunnion ball valve, and a hydrogen station using the ball valve, in which a stepped part is positioned medially in each of inner and outer peripheral surfaces of a resin-made annular seat body, with a seat part on a tip side and a holding part on a rear end side; an attachment groove defined by inner and outer cylinders having a ring-shaped swaging edge part at a tip of a seat retainer; the holding part being attached to the attachment groove; and the swaging edge part of the inner and outer cylinders being in contact with and fixed by being swaged to the stepped part so as to cause the seat part to protrude farther than a swaging position.

Abstract: A structure and method for fastening a ball seat for a ball valve, a trunnion-type ball valve (100), and a hydrogen station using this valve, in which a stepped part (30) is provided in mid-course of each of inner and outer peripheral surfaces of a resin-made annular seat body (21), with a seat part (31) provided on a tip side and a holding part (32) provided on a rear end side; an attachment groove (45) formed of inner and outer cylinders having a ring-shaped swaging edge part (34) is formed at a tip of a seat retainer (22); the holding part (32) is attached to this attachment groove (45); and the swaging edge part (34) of the inner and outer cylinders is closely contacted and fixed by being swaged to the stepped part (30) to cause the seat part (31) to protrude more than a swaging position.

Abstract: A shaft sealing device switches a sealing state and an unsealing state of a fluid, with high sealing performance maintained, because no abrasion accompanies movement of a sealing material or a sealing member, enabling feeding a fluid at a predetermined flow rate, and adjusts the expanding rate of the sealing material with the quantity of an external electric signal and accordingly adjusts the contact face pressure to enable controlling the amount of leakage of the fluid highly precisely, so that it can be used for all applications. The shaft sealing device includes a shaft sealing body formed of a macromolecular material and made expansible or contractible, or deformable, through external electrostimuli applied to a shaft sealing portion disposed in a device body, and flow passages disposed in the shaft sealing portion for feeding the fluid leaked due to the expansion or contraction, or the deformation, of the shaft sealing body.

Abstract: A shaft sealing device switches a sealing state and an unsealing state of a fluid, with high sealing performance maintained, because no abrasion accompanies movement of a sealing material or a sealing member, enabling feeding a fluid at a predetermined flow rate, and adjusts the expanding rate of the sealing material with the quantity of an external electric signal and accordingly adjusts the contact face pressure to enable controlling the amount of leakage of the fluid highly precisely, so that it can be used for all applications. The shaft sealing device includes a shaft sealing body formed of a macromolecular material and made expansible or contractible, or deformable, through external electrostimuli applied to a shaft sealing portion disposed in a device body, and flow passages disposed in the shaft sealing portion for feeding the fluid leaked due to the expansion or contraction, or the deformation, of the shaft sealing body.

Abstract: A polymer actuator is capable of being utilized for any of various drive sources, and the amount of deformation of the polymer actuator can particularly be used also for a valve or shaft-sealing device. The polymer actuator includes a power driver deformed upon receiving electro stimuli and electrodes disposed on the upper and lower surface sides of the power driver in an opposite manner for applying positive and negative electro stimuli to the power driver in a planar fashion. The electrodes have different stimuli application regions to have different electrical field distributions for causing distribution of stress generated in the power driver to be eccentrically located on one of positive and negative sides, thereby bending and deforming the power driver onto a side on which the opposite stimuli application regions do not exist.

Abstract: The object is to provide a polymer actuator capable of securing high sealability in spite of a simple interior structure, controlling opening and closing of the fluid passage or flow rate while increasing the amount of displacement at a small amount of applied voltage, and controlling the flow rate from small flow rate to large flow rate through variation in the applied voltage, thereby enhancing response performance and to provide a valve using the polymer actuator.

Abstract: The object is to provide a polymer actuator capable of being utilized for any of various drive sources, wherein the amount of deformation of the polymer actuator can particularly be used also for a valve or shaft-sealing device. The polymer actuator comprises a power driver deformed upon receiving electro stimuli and electrodes disposed on the upper and lower surface sides of the power driver in an opposite manner for applying positive and negative electro stimuli to the power driver in a planar fashion. The electrodes have different stimuli application regions to have different electrical field distributions for causing distribution of stress-generated in the power driver to be eccentrically located on one of positive and negative sides, thereby bending and deforming the power driver onto a side on which the opposite stimuli application regions do not exist.

Abstract: A shaft sealing device with a simple internal structure switches a sealing state and an unsealing state of a fluid, with high sealing performance maintained, because of no abrasion accompanying the movement of a sealing material or a sealing member, thereby enabling feeding a fluid at a predetermined flow rate, and adjusts the expanding rate of the sealing material with the quantity of an external electric signal and accordingly adjusts the contact face pressure to enable controlling the amount of leakage of the fluid highly precisely, so that it can be used for all applications. The shaft sealing device includes a shaft sealing body formed of a macromolecular material and made expansible or contractible, or deformable, through external electrostimuli applied to a shaft sealing portion disposed in a device body, and flow passages disposed in the shaft sealing portion for feeding the fluid leaked due to the expansion or contraction, or the deformation, of the shaft sealing body.