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 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.

Abstract: A valve is provided without processing junction sites thereof, in which pipes can infallibly be joined with ease only through the reduction in diameter of a housing to be fastened and, at the same time, the valve has appropriate flexibility relative to the joined pipes and is capable of absorb vibration etc., thereby exhibiting excellent durability. Furthermore, the valve has a diameter-reducible joint part, enables joining the pipes to the opposite sides thereof separately individually and can always maintain high sealability even when the pipes are joined thereto or detached therefrom, thus excelling in cost.

Abstract: A valve having a diameter-reducible joint includes a diameter-reducible housing having a flow path therein and accommodating a seal sleeve formed of rubber, a valve mechanism provided with a valve element and built in the housing to enable switching of the flow path and controlling of a flow rate, and a junction pipe having a junction end joined with the seal sleeve to the diameter-contracted joint in a tightly sealed fashion through diameter reduction of the housing. A plumbing system comprising a pipe that has a terminal and a valve which comprises a diameter-reducible joint part having diameter-enlarging and -reducing functions, a housing having one or both joint portions enlarged and reduced in diameter to join the pipe thereto and a disc disposed within the housing and which is attached to the terminal of the pipe.

Abstract: The invention provides a ball valve excelling in economy due to the efforts devoted to the reduction of cost, enjoying light weight and high reliability, manifesting high and uniform accuracy, and enabling manufacture of compact finished products having a small interface dimension, and provides a method for the production of the ball valve. The ball valve includes a body formed from a pipe having a predetermined length by subjecting opposite terminal parts (ends) of the pipe to a plastic processing including flaring and diametrical contraction. The body has at a central position a seat-shaping part (seat) formed with a stem-inserting hole, a stem inserted into the stem-inserting hole, a ball disposed non-rotatably at a lower terminal of the stem, and a pair of inserting members having an annular shape forced into the body from opposite terminals of the body. Opposite terminal faces of the body are compression-formed so that the pair of inserting members receive and support the ball rotatably.

Abstract: The invention provides a ball valve excelling in economy due to the efforts devoted to the reduction of cost, enjoying light weight and high reliability, manifesting high and uniform accuracy, and enabling manufacture of compact finished products having a small interface dimension, and provides a method for the production of the ball valve. The ball valve includes a body formed from a pipe having a predetermined length by subjecting opposite terminal parts (ends) of the pipe to a plastic processing including flaring and diametrical contraction. The body has at a central position a seat-shaping part (seat) formed with a stem-inserting hole, a stem inserted into the stem-inserting hole, a ball disposed non-rotatably at a lower terminal of the stem, and a pair of inserting members having an annular shape forced into the body from opposite terminals of the body. Opposite terminal faces of the body are compression-formed so that the pair of inserting members receive and support the ball rotatably.

Abstract: The invention provides a ball valve excelling in economy due to the efforts devoted to the reduction of cost, enjoying light weight and high reliability, manifesting high and uniform accuracy, and enabling manufacture of compact finished products having a small interface dimension, and provides a method for the production of the ball valve. The ball valve includes a body formed from a pipe having a predetermined length by subjecting opposite terminal parts (ends) of the pipe to a plastic processing including flaring and diametrical contraction. The body has at a central position a seat-shaping part (seat) formed with a stem-inserting hole, a stem inserted into the stem-inserting hole, a ball disposed non-rotatably at a lower terminal of the stem, and a pair of inserting members having an annular shape forced into the body from opposite terminals of the body. Opposite terminal faces of the body are compression-formed so that the pair of inserting members receive and support the ball rotatably.

Abstract: A rotary valve includes a main valve body that includes a body, a seat disposed in the body and a valve body disposed in the body so that the valve body is rotatable through the seat that are modulated as a common component part. A stem pierces the body and imparts opening and closing motions to the valve body. An attaching-detaching part is disposed at a position at which the stem pierces the body. An operating part is disposed on the stem and is adapted to operate the valve body. A coupling part is detachably fastened at one end thereof to the attaching-detaching part and is mounted at the other end thereof on the operating part for joining the attaching-detaching part and the operating part.

Abstract: A rotary valve includes a main valve body that includes a body, a seat disposed in the body and a valve body disposed in the body so that the valve body is rotatable through the seat that are modulated as a common component part. A stem pierces the body and imparts opening and closing motions to the valve body. An attaching-detaching part is disposed at a position at which the stem pierces the body. An operating part is disposed on the stem and is adapted to operate the valve body. A coupling part is detachably fastened at one end thereof to the attaching-detaching part and is mounted at the other end thereof on the operating part for joining the attaching-detaching part and the operating part.

Abstract: The invention provides a ball valve excelling in economy owing to the efforts devoted to the reduction of cost, enjoying light weight and high reliability, manifesting high and uniform accuracy, and enabling manufacture of compact finished products having a small interface dimension and provides a method for the production of the ball valve. The ball valve includes a body formed from a pipe having a predetermined length by subjecting opposite terminal parts of the pipe to a plastic processing including flaring and diametrical contraction, the body having at a central position a seat-producing part formed with a stem-inserting hole, a stem inserted into the stem-inserting hole, a ball disposed non-rotatably at a lower terminal of the stem, and a pair of inserting members of an annular shape forced into the body from opposite terminals of the body, opposite terminal faces of the body being compression-formed so that the pair of inserting members receive and support the ball rotatably.

Abstract: A rotary valve includes a main valve body that including a body, a seat disposed in the body and a valve body disposed in the body so that the seat is rotatable through the seat, and being modulated as a common component part; a stem piercing the body and imparting opening and closing motions to the valve body; an attaching-detaching part disposed at a position at which the stem pierces the body; an operating part disposed on the stem and adapted to operate the valve body; and a coupling part detachably fastened at one end thereof to the attaching-detaching part and mounted at the other end thereof on the operating part for joining the attaching-detaching part and the operating part.

Abstract: A pipe joint includes a joint body having an internal thread portion formed in the interior thereof, a bush having formed on the outer periphery thereof an external thread portion helically meshed with the internal thread portion of the joint body, a gasket accommodated within the interior of the joint body, and a retainer having formed on one end thereof on the side of the joint body a flange of increased wall thickness which is pushed toward the joint body by the end face of the external thread portion of the bush. The flange of the retainer may be provided with at least one engaging projection extending radially outwardly from the outer periphery thereof and, in this case, the internal thread portion of the joint body is provided therein with at least one lock portion which is engaged with the at least one engaging projection of the flange.

Abstract: A valve seat for use in a ball valve has a shoulder portion, an elastic lip portion, a circumferential non-contact surface, at least one recess and an intersecting portion. The shoulder portion has an engaging surface on its rear surface which contacts the contact surface of the valve casing perpendicular to the flow passage. The non-contact surface is formed on the rear face of the valve seat between the engaging surface and the lip portion and stepped away from the contact surface. The recess is formed in the shape of a groove in the non-contact surface and has its bottom flush with the rear surface of the lip portion stepped away from the contact surface in such a manner that the lip portion is not thinned so as to ensure sufficient strength of the lip portion. The intersecting portion is disposed between the engaging surface and the non-contact surface.