Abstract: Seat members 31 are held in a state of being movable with respect to first slide members 21 or second slide members 22 correspondingly. By rotating screws 39 in directions to increase the distances d between surfaces A of the first slide members 21 or the second slide members 22 and surfaces B of the seat members 31, chucks 25 are moved in directions to increase the distance between the chucks to apply pretension to a test piece correspondingly. When backlash in a force transmission system from a support part to the respective chucks 25 is eliminated, a biaxial tensile test is started.

Abstract: When mounting a grip 10 on a cross head 73, a pin 62 and an adapter 50 are removed from a joint 40. Then, a boss 13 of the grip 10 is inserted into a hollow part 45 of the joint 40, and the pin 62 is inserted into a through-hole 14 formed in the boss 13 of the grip 10 and a hole part 42 formed in a tubular body 41 of the joint 40. When mounting a platen 30 on the cross head 73, the adapter 50 is mounted on the joint 40. In addition, the platen 30 is mounted on the adapter 50. Further, a set screw is inserted into a hole part 52 of the adapter 50.

Abstract: Seat members 31 are held in a state of being movable with respect to first slide members 21 or second slide members 22 correspondingly. By rotating screws 39 in directions to increase the distances d between surfaces A of the first slide members 21 or the second slide members 22 and surfaces B of the seat members 31, chucks 25 are moved in directions to increase the distance between the chucks to apply pretension to a test piece correspondingly. When backlash in a force transmission system from a support part to the respective chucks 25 is eliminated, a biaxial tensile test is started.

Abstract: When mounting a grip 10 on a cross head 73, a pin 62 and an adapter 50 are removed from a joint 40. Then, a boss 13 of the grip 10 is inserted into a hollow part 45 of the joint 40, and the pin 62 is inserted into a through-hole 14 formed in the boss 13 of the grip 10 and a hole part 42 formed in a tubular body 41 of the joint 40. When mounting a platen 30 on the cross head 73, the adapter 50 is mounted on the joint 40. In addition, the platen 30 is mounted on the adapter 50. Further, a set screw is inserted into a hole part 52 of the adapter 50.

Abstract: A material tester using a connection structure is provided. A shaft carved with a male thread on a root of the shaft is formed with a fixture, and a lock nut is screwed against the male thread. A connection component formed with a hole for embedding the shaft is fixed on a loading component (table). In a state that a pin is inserted into lateral holes formed in the shaft and the connection component, gaps between the pin and the lateral holes are eliminated by fastening the lock nut. In addition, by forming a taper portion and a taper hole respectively en the lock nut and in the hole of the connection component, the taper portion is complementally engaged with the taper hole during fastening the lock nut, so as to center on the fixture. Therefore, the fixture can be always connected to the connection component in a preset position.

Abstract: An adjusting unit in a feedback loop for controlling a hydraulically operated-type load mechanism consists of two portions both adapted to effect proportional action and derivative action. Weights are applied to these two portions independently. Hence, an output y can be made to follow sudden changes in a target value r with fast response without the occurrence of overshoots, and the effect of a disturbance input w is alleviated to a maximum. In addition, since integral action is not effected in the adjusting portions, the term of 1/s2 is not included in transfer functions of inputs and outputs, thereby realizing stability of control.

Abstract: An adjusting unit in a feedback loop for controlling a hydraulically operated-type load mechanism consists of two portions both adapted to effect proportional action and derivative action. Weights are applied to these two portions independently. Hence, an output y can be made to follow sudden changes in a target value r with fast response without the occurrence of overshoots, and the effect of a disturbance input w is alleviated to a maximum. In addition, since integral action is not effected in the adjusting portions, the term of 1/s2 is not included in transfer functions of inputs and outputs, thereby realizing stability of control.