Static structures (e.g. – buildings) – Means compensating earth-transmitted force
Reexamination Certificate
1999-09-14
2001-05-01
Stodola, Daniel P. (Department: 3634)
Static structures (e.g., buildings)
Means compensating earth-transmitted force
C052S167700
Reexamination Certificate
active
06223483
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a vibration damping mechanism and an anti-earthquake wall material for reducing the vibration of a structure such as a building.
2. Description of the Prior Art
A vibration damping mechanism which uses a viscoelastic body to efficiently reduce the vibration of a structure has been given in Japanese Unexamined Patent Publication No. 7 (1995)-247727. According to this patent publication, there is disclosed a vibration damping mechanism in which a first pivot and a second pivot are mounted to opposed frame members of a structure, respectively, with an appropriate spacing, a first fixed plate which is rotatable with respect to the first pivot, and a second fixed plate which is rotatable with respect to the second pivot are opposed with a gap between them, and a viscoelastic body is filled into this gap, and with this vibration damping mechanism, the viscoelastic body is selected according to the conversion factor &bgr;=L/h.
With the conventional vibration damping mechanism, the viscoelastic body is selected according to the conversion factor &bgr;=L/h, which makes it difficult to manufacture the vibration damping mechanism. In addition, the vibration damping mechanism using a viscoelastic body is for large-scale buildings, and to apply it for small-scale buildings, such as a wooden house or a light-weight steel-frame house, a convenient mechanism is demanded in consideration of the cost. The present invention offers a vibration damping mechanism which is still more convenient in configuration, and can efficiently reduce the vibration of a structure.
Thin-plate anti-earthquake wall materials are connected to a framework (beam or column) for a building or the like, and when the deformation of the framework is small, the thin plate provides a high rigidity in conjunction with the frame work. However, when the deformation of the framework is great, the thin plate buckles (so-called wrinkles are produced), resulting in the rigidity being reduced. For this reason, such buckling has been considered to be harmful, and for thin-plate buckling phenomena, the buckling deformation and load have been determined with high accuracy, and reasonable reinforcing methods for preventing the buckling have been devised. For example, the shear load bearing material used in an airplane, a vehicle, a ship, a bridge, a building or the like is an aggregate of a thin plate and a number of reinforcing materials, being free from elastic buckling, in other words, being configured so that plastic buckling can be caused, and with the plastic buckling, the distortion energy is absorbed and the vibration is reduced. Consequently, because the buckling load for a shear load bearing material (having a length of the shorter side of “a” and a thickness of “t”) is in proportion to (t/a)
2
, the value of (t/a) is made sufficiently large to prevent buckling from being caused within the limit of elastic deformation.
Therefore, a framework to which an anti-earthquake wall material free from elastic buckling is connected has practically no capacity to absorb the vibration energy, providing a construction which has strength, but rocks significantly in an earthquake or a typhoon. On the other hand, a framework to which an anti-earthquake wall material causing plastic buckling is connected provides an effect of preventing rocking of a building by absorbing the plastic distortion, but brings about a substantial reduction in rigidity, the external force to be born by the anti-earthquake wall material being transferred to the framework connected to the anti-earthquake wall material, which results in an increase in deformation of the framework, leading to plasticization of the framework, and at the subsequent stage, a collapse of the structure. In other words, if an anti-earthquake wall material free from elastic buckling is used, a structure which significantly rocks in an earthquake or a typhoon is provided, and only if the anti-earthquake wall material has been plasticized through a great deformation in an earthquake, is the degree of rocking of with the structure decreased. However, if an anti-earthquake wall material is an elastic body, and yet is provided with an energy absorbing capability, a structure with which the degree of rocking is low, and which will not collapse can be produced. As the energy absorption mechanism, a damper is available, but the damper will not contribute any increase in strength and rigidity. The present invention offers an anti-earthquake wall material which is provided with features of strength, rigidity, and energy absorbing capability.
SUMMARY OF THE INVENTION
The present invention offers a vibration damping mechanism for a structure which comprises a first fixed plate which is fixed to an upper frame member of a structure and is provided with a first pivot, and a second fixed plate which is fixed to a lower frame member opposed to the upper frame member with an appropriate spacing and is provided with a second pivot. A connecting plate which is rotatably mounted with the first pivot and the second pivot is opposed to the first fixed plate and the second fixed plate with a gap being provided, and a viscoelastic body is filled into the gap between the connecting plate and the first fixed plate, and the gap between the connecting plate and the second fixed plate. Thus, the connecting plate is configured so that it can be turned with the first pivot and the second pivot, which means that the viscoelastic body can be selected according to the position of the first pivot and the second pivot, which allows a vibration damping mechanism can be manufactured conveniently.
Further, the present invention offers an anti-earthquake wall material which is connected to a framework for a building, etc., in which, on one side or both sides of a base plate material to be connected to the framework, a space is formed with an auxiliary plate material smaller than the base plate material. A viscoelastic body is filled into the space, and the base plate material is selected so that it can cause elastic buckling.
Further, the present invention offers an anti-earthquake wall material in which the auxiliary plate material is an auxiliary plate material which can deform with no resistance.
Further, the present invention offers an anti-earthquake wall material which is connected to a framework for a building, etc., in which, on one side or both sides of a base plate material to be connected to the framework, a space is formed with an auxiliary plate material smaller than the base plate material; a lead plate material is loaded in the space along the auxiliary plate material and a viscoelastic body is filled into the space. The base plate material is selected so that it can cause elastic buckling.
Further the present invention offers an anti-earthquake wall material which is connected to a framework for a building, etc., in which the anti-earthquake wall material is rotatably mounted to the framework, a fitting groove and a projection are formed in the joint between adjacent anti-earthquake wall materials or to a column, and in that place, a viscoelastic body is sandwiched for jointing.
Thus, by filling a viscoelastic body into a space formed with the use of an auxiliary plate material on one side or both sides of a base plate material, and configuring so that the auxiliary plate material smaller than the base plate material can cause elastic buckling, rigidity can be provided and the vibration energy can be absorbed. Adjacent anti-earthquake wall materials are jointed with a viscoelastic body being provided in the joint, thus providing a waterproof effect, and the degree of rocking of a framework can be reduced by the vibration energy absorption function of the viscoelastic body.
REFERENCES:
patent: 4533109 (1985-08-01), Delam
patent: 5083404 (1992-01-01), Schulte
patent: 5271197 (1993-12-01), Uno et al.
patent: 5682712 (1997-11-01), Kemeny
patent: 5732802 (1998-03-01), Tsukagoshi
patent: 5875589 (1999-03-01), Lai et al.
Cohen Curtis A.
Nixon & Peabody LLP
Stodola Daniel P.
Studebaker Donald R.
LandOfFree
Vibration damping mechanism and anti-earthquake wall material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vibration damping mechanism and anti-earthquake wall material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vibration damping mechanism and anti-earthquake wall material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2484059