Abstract: To provide a vacuum valve with an improved endurance of a bellows, a vacuum valve comprises: a valve section including a first port, a second port, a valve seat provided between the first and second ports, and a valve element movable into or out of contact with the valve seat; an actuator section including an orifice through which an operating fluid is supplied to the actuator section, and a piston coupled to the valve element, the piston being allowed to operate according to changes of pressure of the operating fluid to apply a driving force to the valve section; and a bellows which can be contracted and elongated as the valve element vertically moves upward and downward. The orifice is designed to have an effective sectional area determined so that an operating speed of the valve element and the piston is controlled to a predetermined speed for preventing damage of the bellows.

Abstract: To provide a vacuum valve with an improved endurance of a bellows, a vacuum valve comprises: a valve section including a first port, a second port, a valve seat provided between the first and second ports, and a valve element movable into or out of contact with the valve seat; an actuator section including an orifice through which an operating fluid is supplied to the actuator section, and a piston coupled to the valve element, the piston being allowed to operate according to changes of pressure of the operating fluid to apply a driving force to the valve section; and a bellows which can be contracted and elongated as the valve element vertically moves upward and downward. The orifice is designed to have an effective sectional area determined so that an operating speed of the valve element and the piston is controlled to a predetermined speed for preventing damage of the bellows.

Abstract: The present invention provides an adhesive composition (a UV-curable resin composition) comprising a bisphenol type epoxy(meth)acrylate (A), a di(meth)acrylate compound (B) having a cyclic ether structure, and a photo-polymerization initiator (C), and a bonded optical disk which is adhered with a cured product of said adhesive composition. By adhering with said composition optical disk substrates having a translucent reflection film or a total reflection film comprising silver, a silver alloy, or the like, and obtaining a bonded optical disk, high durability equivalent to those of conventional bonded optical disks in which a translucent reflection film of gold is used, and high adhesion strength between a reflection film and an adhesive cured product, and a polycarbonate substrate and an adhesive cured product, can be obtained.

Abstract: A computer display device with digital RGB color signal lines, and horizontal and vertical synchronous signal lines. The controller comprising a means for taking out, from one of the digital RGB color signal lines which consists of an N bit digital signal, a black level signal defined as "0" or "1" in all N bits, and a means for adding the black level signal being taken out to either one of said horizontal and vertical synchronous signal lines. In addition to the controller, the present invention provides a display device including a means, provided within the display device, for extracting said black level signal from the synchronous signal with the black level signal being added, and a means for maintaining a black level potential of the display device at a predetermined value in response to the black level signal being extracted.