Kajima Corporation

Hitachi Kizai, Inc.

Haruhiko Kurino

Yoshinori Matsunaga

Toshikazu Yamada

Naoki Niwa

Yuji Kotake

Shii Sen

There is disclosed a damping coefficient switching-type hydraulic damper that may automatically switch a damping coefficient without needing supply of energy from the outside at all, and also may always surely exert an energy absorption capacity greater than that of a typical hydraulic damper. While a piston is moving in a direction A, a mechanical drive means composed of a straight gear and a crank mechanism allows an on-off control operation valve, that is, a flow regulating valve to be placed in a closed state, and a damping coefficient is switched to a maximum value Cmax. When a movement of the piston is turned in a direction B at a left-side maximum point of amplitude, the mechanical drive means works to once open the flow regulating valve to perform elimination of a load, so that the damping coefficient is switched to a minimum value (Cmin). When the piston further moves in the direction B, the mechanical drive means works to close the flow regulating valve again, and the damping coefficient is returned to the maximum value (Cmax). Similar working to the above is also applied to a right-side maximum point of amplitude, and seismic response control is attained with repetition of the above operations.

Damping coefficient switching-type hydraulic damper

A hydraulic damper used for reducing shaking of a structure, for example in an earthquake. The hydraulic damper has a cylinder, a piston movable in a reciprocating manner within the cylinder, hydraulic chambers at opposite sides of the piston, and a single on-off control valve. There is a passage for connecting both of the hydraulic chambers and is on-off controlled to change a damping coefficient. A damping coefficient switching-type hydraulic damper is provided between a piston rod and the on-off control valve. A first damping coefficient is attained when the on-off control valve is maintained in a closed state for movement of said piston in one direction, and a second damping coefficient is attained when the on-off control valve is opened. A mechanical drive for the control valve may be a straight gear operatively attached to the piston rod of the cylinder, and a crank mechanism that works with the straight gear to on-off control the control valve.

Attenuation coefficient switching type hydraulic damper

An oil pressure damper device for an architectural structure and a monitor and control system of the damper device without requiring an exclusive network for connecting between the damper devices and the monitor and control system, and is able to monitor operations without regard to the distance between the damper devices and the monitor system. The oil pressure damper device includes a detection unit for detecting conditions of the damper device, a communication unit for transmitting information detected by the detection unit through a public communication network and/or a local area network, and a monitor for receiving the information from the communication unit and monitoring the conditions of the damper devices of the architectural structure.

Damper device for building, and monitor and control system for damper device

There is disclosed a seismic response control method for a structure, comprising the steps of installing a seismic response control device in a structural component of stiffness K.sub.f ; and controlling a characteristic of story restitutive force based of story restitutive force Q (=Q.sub.s +F) given as the sum of restitutive force Q.sub.s of the structural component installed with the seismic response control device and force F generated from the seismic response control device so as to maintain or vary the characteristic of story restitutive force, which is shown on a coordinate plane as the relation between amplitude D(t) and story restitutive force Q(t) of the structural component portion, in the specific form, in response to the kaleidoscopic state of vibration. The seismic response control device is controlled efficiently with a sensor for measuring a state value of a device part and a simple configuration on microprocessor level.

Growing community of inventors

Tokyo, Japan

Haruhiko Kurino