Abstract: Provided is a nut and a bolt tightening method for fastening an object, wherein a tightening force is applied on the object by rotating a nut or a bolt in a state in which a predetermined tension force is applied on the bolt in the axial direction of the bolt. When the tensile force exerted on the bolt decreases as the tightening force increases and after a timing when an inflection point occurs in a time course change in a ratio of an amount of change in the tensile force exerted on the bolt to an amount of change in an angle of rotation of the nut or the bolt, the tightening resulting from the rotation of the nut or bolt is terminated and the tensile force applied on the bolt is removed.

Abstract: Tightening device can fasten a fastening element by a target tightening force with good accuracy and facilitate automation. The tightening device includes a cylindrical drive socket holding a nut in the lower end opening thereof; a nut holder disposed inside the drive socket, a bolt passing through a bottom thereof, and regulating movement of the nut held by the drive socket toward the tip end of a threaded par; a tension rod which is disposed inside the nut holder and the lower end face of which has a threaded hole into which a portion of the threaded part that is further on the tip end side than the nut is screwed; a sensor for detecting tension force; a first motor for turning the tension rod around an axis that extends in the vertical direction; and a second motor for turning the drive socket around an axis.

Abstract: A fastening device for fastening a bolt to a fastening target object, wherein the bolt has a bolt head female screw section in an inner circumferential surface of a recess provided in an upper surface of a bolt head section. The fastening device includes a tension rod having a rod male screw section engaging the bolt head female screw section; a drive socket circumferentially surrounding the tension rod and having a lower end section with a grasper for laterally grasping the bolt head section; a supporter circumferentially surrounding the drive socket and having a lower end section protruding downward beyond a lower end section of the drive socket; a sensor for sensing compression force acting on the supporter in the upward/downward direction; a first motor for rotating the tension rod around an axis extending in the upward/downward direction; and a second motor for rotating the drive socket around the axis.

Abstract: A fastening device for fastening a bolt to a fastening target object, wherein the bolt has a bolt head female screw section in an inner circumferential surface of a recess provided in an upper surface of a bolt head section. The fastening device includes a tension rod having a rod male screw section engaging the bolt head female screw section; a drive socket circumferentially surrounding the tension rod and having a lower end section with a grasper for laterally grasping the bolt head section; a supporter circumferentially surrounding the drive socket and having a lower end section protruding downward beyond a lower end section of the drive socket; a sensor for sensing compression force acting on the supporter in the upward/downward direction; a first motor for rotating the tension rod around an axis extending in the upward/downward direction; and a second motor for rotating the drive socket around the axis.

Abstract: In a fastening device for fastening a bolt, a male thread is formed on a side surface of a bolt head part, and a part to be engaged is formed on a top surface of the bolt head part. The fastening device includes a bit having a tension rod having a rod female thread part, and an engaging part installed inside the tension rod and engaging the engaged part, the bit causing the bolt to rotate where the engaged part and engaging part are engaged; a supporter surrounding the tension rod in the circumferential direction such that the lower end part thereof protrudes below the lower end part; a sensor for sensing vertical compression force acting on the supporter; a first motor for causing the bit to rotate about the axis; and a second motor for causing the tension rod to rotate about the vertically extending axis.

Abstract: In a fastening device for fastening a bolt, a male thread is formed on a side surface of a bolt head part, and a part to be engaged is formed on a top surface of the bolt head part. The fastening device includes a bit having a tension rod having a rod female thread part, and an engaging part installed inside the tension rod and engaging the engaged part, the bit causing the bolt to rotate where the engaged part and engaging part are engaged; a supporter surrounding the tension rod in the circumferential direction such that the lower end part thereof protrudes below the lower end part; a sensor for sensing vertical compression force acting on the supporter; a first motor for causing the bit to rotate about the axis; and a second motor for causing the tension rod to rotate about the vertically extending axis.

Abstract: Tightening device can fasten a fastening element by a target tightening force with good accuracy and facilitate automation. The tightening device includes a cylindrical drive socket holding a nut in the lower end opening thereof; a nut holder disposed inside the drive socket, a bolt passing through a bottom thereof, and regulating movement of the nut held by the drive socket toward the tip end of a threaded par; a tension rod which is disposed inside the nut holder and the lower end face of which has a threaded hole into which a portion of the threaded part that is further on the tip end side than the nut is screwed; a sensor for detecting tension force; a first motor for turning the tension rod around an axis that extends in the vertical direction; and a second motor for turning the drive socket around an axis.

Abstract: Provided is a nut and a bolt tightening method for fastening an object, wherein a tightening force is applied on the object by rotating a nut or a bolt in a state in which a predetermined tension force is applied on the bolt in the axial direction of the bolt. When the tensile force exerted on the bolt decreases as the tightening force increases and after a timing when an inflection point occurs in a time course change in a ratio of an amount of change in the tensile force exerted on the bolt to an amount of change in an angle of rotation of the nut or the bolt, the tightening resulting from the rotation of the nut or bolt is terminated and the tensile force applied on the bolt is removed.

Abstract: A tightening tool such as a torque wrench is provided in which electric power can be fed to an electronic circuit with eliminating the need for a battery and achieving daily maintenance-free. In the tightening tool, when a tightening torque has reached a set torque value and a torque limiter is actuated, an electronic circuit unit that has obtained a detection signal outputted from a torque limiter actuation detection unit outputs a tightening completion signal. The tightening tool has a power generation unit for feeding electric power to the electronic circuit unit at least during the actuation of the torque limiter. The power generation unit performs photovoltaic power generation, electromagnetic induction power generation, power generation by conversion from mechanical energy into electrical energy, or temperature difference power generation.

Abstract: A tightening tool such as a torque wrench is provided in which electric power can be fed to an electronic circuit with eliminating the need for a battery and achieving daily maintenance-free. In the tightening tool, when a tightening torque has reached a set torque value and a torque limiter is actuated, an electronic circuit unit that has obtained a detection signal outputted from a torque limiter actuation detection unit outputs a tightening completion signal. The tightening tool has a power generation unit for feeding electric power to the electronic circuit unit at least during the actuation of the torque limiter. The power generation unit performs photovoltaic power generation, electromagnetic induction power generation, power generation by conversion from mechanical energy into electrical energy, or temperature difference power generation.

Abstract: A torque wrench equipped with a cam-type torque detection mechanism is provided which is capable of detecting a torque with high accuracy, providing a non-unusual-feeling of handle operation after torque has been detected, and enabling tightening of fastened members such as bolts with safety.

Abstract: To make improvements in torque wrenches with a torque limiter that uses a cam mechanism and to provide a torque wrench that realizes more stable operation and is capable of highly precise tightening. In a torque wrench with a torque limiter that uses a cam mechanism, a solid columnar roller member 14 is engaged with a cam part 7 of a cam shaft 8 such that it is rotatably supported by a roller support lever member 12 mounted in a head portion 2 such as to be rotatable around a support shaft 16 and such that it is pressed against the cam part 7 by a spring force transmitting rod 18 biased by a torque setting spring. The roller support lever member 12 is configured such that the distance r2 from the support shaft 16 to a point of application of force of the spring force transmitting rod 18 is longer than the distance r1 from the support shaft 16 to the roller member 14.

Abstract: A torque wrench equipped with a cam-type torque detection mechanism is provided which is capable of detecting a torque with high accuracy, providing a non-unusual-feeling of handle operation after torque has been detected, and enabling tightening of fastened members such as bolts with safety.

Abstract: To make improvements in torque wrenches with a torque limiter that uses a cam mechanism and to provide a torque wrench that realizes more stable operation and is capable of highly precise tightening. In a torque wrench with a torque limiter that uses a cam mechanism, a solid columnar roller member 14 is engaged with a cam part 7 of a cam shaft 8 such that it is rotatably supported by a roller support lever member 12 mounted in a head portion 2 such as to be rotatable around a support shaft 16 and such that it is pressed against the cam part 7 by a spring force transmitting rod 18 biased by a torque setting spring. The roller support lever member 12 is configured such that the distance r2 from the support shaft 16 to a point of application of force of the spring force transmitting rod 18 is longer than the distance r1 from the support shaft 16 to the roller member 14.

Abstract: A pixel electrode arranged opposite to a counter electrode with liquid crystal filled in therebetween has a plurality of through holes spaced from one another. When a foreign substance adheres to the pixel electrode, the pixel electrode is partly removed to connect some of the through holes to each other, so that a portion to which the foreign substance adheres is removed from the pixel electrode. Accordingly, when a conductive foreign substance adheres to the pixel electrode, an electric contact between the pixel electrode and counter electrode can be avoided while making smaller a portion to be removed from the pixel electrode. Therefore, even when electrode pieces occur when partly removing the pixel electrode, the electrode pieces can be reduced in amount and prevented from being adhered to the surroundings. As a result, the occurrence of another pixel defect can be suppressed.

Abstract: A gasket integrated with a cover wherein a gasket material composed of a thermoplastic elastomer composition is integrally fixed to the cover having a shape of multistep contraction over at least two contraction steps, a gasket wherein the cover and the gasket are integrally molded and after molding, are subjected to a heating treatment at a temperature not lower than the temperature at which an adhesive component in materials constituting the gasket initiates crystal fusion or glass transition, or a gasket wherein the cover and the gasket are integrally molded and a covering layer composed of a fluoropolymer is formed on the gasket surface on atmospheric side are proposed. According to the present invention, a gasket integrated with a cover for a hard disc device which gasket is excellent in adhesive property and productivity, and is minimized in permeability and penetration of substances is provided.

Abstract: The invention relates to a process for producing a gasket for hard disc equipment which is integrated with a cover member by extruding a gasket material from an extrusion orifice of a three-dimensional automatic coating controlling apparatus onto the cover member and then curing the extruded gasket material, wherein a ratio (h/w) of a height (h) of the gasket to a line width (w) of the gasket on a joint surface between the gasket and the cover member is in the range of 0.8 to 3.0 in a 80% or more portion of the gasket.

Abstract: A gasket integrated with a cover wherein a gasket material composed of a thermoplastic elastomer composition is integrally fixed to the cover having a shape of multistep contraction over at least two contraction steps, a gasket wherein the cover and the gasket are integrally molded and after molding, are subjected to a heating treatment at a temperature not lower than the temperature at which an adhesive component in materials constituting the gasket initiates crystal fusion or glass transition, or a gasket wherein the cover and the gasket are integrally molded and a covering layer composed of a fluoropolymer is formed on the gasket surface on atmospheric side are proposed. According to the present invention, a gasket integrated with a cover for a hard disc device which gasket is excellent in adhesive property and productivity, and is minimized in permeability and penetration of substances is provided.

Abstract: Molten metal is poured into a substantially cylindrical mold from its bottom while the mold is being rotated about its vertical center axis. The ingot-making apparatus comprises a substantially cylindrical mold, stool, vertical pouring channel communicating with a runner provided in the stool, metal receiver communicating with the top of the pouring channel, and a rotary table on which the mold is placed through the stool. The metal receiver is shaped like a body of rotation formed by rotating a curve having an opening at the top in a vertical plane about the axis of rotation of the rotary table.