Robinson Seismic Limited

Damping Systems Limited

Other

Oiles Corporation

William Henry Robinson

Ikuo Shimoda

Tsukasa Kishizono

An energy absorbing bearing with a primary application in the seismic isolation of structure from the ground or parts of other structures. It may also be used to dampen other forces on structures on which it is installed. The bearing consists of end plates separated by a laminate of resilient and stiffening layers. There is a plastically deformable insert within the laminate. The laminate interfaces with the end plates in each bearing and is secured near the central axis from end plate to end plate, but not near the peripheries. The advantage provided is allowing a wider range of forces to be absorbed than with known bearings of this type.

Energy absorber

The invention described is a system for seismic isolation or vibration of structures which is simple, relatively inexpensive and readily used for smaller structures. It involves use of bearings comprising a ball (,) and ball seats (,) interposed between the structure and its foundation. Either the ball itself (,) or the seat surface (,) on which it rolls is compressible, the resistance to that compression providing a frictional braking force resisting rolling of the ball. This serves to dampen relative movement between the structure and its foundation. There are described several alternative constructions of the friction ball which is the preferred central element in the bearing device. There may be a plurality of balls (,) in each combination of balls and seats.

An extrusion damper for interposing between two members to absorb energy of motion which may be induced between the two comprises an outer jacket (,) surrounding a body of plastically deformable energy absorbing material (,) such as lead and a shaft (,) which moves through the outer jacket to deform the lead during induced motion. The body of lead may be fixed relative to the outer jacket and the shaft has a portion of reduced diameter (,) which moves through the lead. Alternatively the body of lead may be fixed to the shaft and the outer jacket has a portion of enlarged diameter (,) through which the energy absorber passes. The body of energy absorbing material may optionally be subjected to approximately hydrostatic pressure preferably exceeding the shear yield stress of the energy absorbing material.

Damper

Vibration isolation apparatus

Energy absorbers and methods of manufacture

A cyclic shear energy absorber interposed or to be interposed between members of a structure which may be caused by incoming energy to oscillate relative to each other. Such an absorber would have application in isolating a structure such as a building or nuclear power station from movements of its foundation caused by an earthquake. Similarly such an absorber could also dampen movement of a building caused by high wind. The absorber of the invention makes use of the fact that when a metal is plastically deformed, energy is absorbed. Lead which is the best example of such a material from a practical point of view is able to recover and recrystallize within a second or so, thus making the energy absorbing material available to absorb energy resulting from a relative movement opposite to that that caused the immediately preceding deformation under shear.

Growing community of inventors

Eastbourne, New Zealand

William Henry Robinson