JP4640958B2 - Friction damper - Google Patents

Description

  The present invention relates to a friction damper used for vibration control of structures such as buildings and bridges.

  Conventionally, in order to improve the earthquake resistance of structures composed of columns and beams, seismic members such as struts and wands have been used, but in order to improve the earthquake resistance performance of structures, In some cases, a vibration control device such as

  Among dampers, there are hydraulic dampers that use fluid resistance, friction dampers that use frictional resistance between members, and hysteretic dampers that use plastic deformation of metals such as steel. Is widely used because it is easy to maintain.

The friction damper usually adjusts the frictional force generated on the contact surface between the plates by fastening a plurality of plates using fastening means such as bolts, and the following is known (patent document) 1).
Japanese Patent Laid-Open No. 11-343675

  However, in such a friction damper, when a large frictional force is to be obtained, the axial force of the bolt must be increased. Therefore, the number and diameter of the bolts must be increased, resulting in an increase in size and cost of the device. It was high.

  The present invention has been made in view of such problems, and an object thereof is to provide a friction damper capable of easily obtaining a large frictional force at low cost.

To achieve the above object, the present invention comprises a plurality of plate members provided slidably with each other, and a pressing means for pressing said plurality of plate members, the, among the plurality of plate members The first plate member has a convex portion and / or a groove portion on one surface , and the second plate member has a groove portion and / or a convex portion on one surface , and the first plate member and the second The plate member faces, the convex portion and / or the groove portion of the first plate member and the groove portion and / or the convex portion of the second plate member can be slidably contacted, and the convex portion and the groove portion The sliding surface with which the sliding contact is provided is inclined with respect to the plane formed by the sliding direction and the pressing direction, and is configured to sandwich the second plate member with a pair of the first plate members. In the longitudinal direction of the second plate member, a long hole is provided, and the pressing means is an upper surface of the first plate member. An elastic member provided, the elastic body, and the elongated hole and a bolt penetrating through a pair of said first plate member, is constituted by a nut provided at one end of the bolt, the said protrusion groove There line energy absorbed by the friction during sliding of a friction damper, which is a adjustable frictional force by adjusting the tightening force of the bolt.
The cross-sectional shape of the cross section orthogonal to the sliding direction of the convex portion or the groove portion may be a triangle, a trapezoid, other polygonal shapes, or a substantially circular shape.

  According to the present invention, it is possible to provide a friction damper that can easily obtain a large frictional force at low cost.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail based on the drawings. FIG. 1 is a perspective view showing a friction damper 1 according to this embodiment, and FIG. 2 is a cross-sectional view of FIG. 3 is a view taken in the direction of arrow A1 in FIG.

As shown in FIGS. 1, 2 and 3, the friction damper 1 is provided with an intermediate plate 3 and a connecting plate 5 on the upper surface of the outer plate 7b, and on the upper surfaces of the intermediate plate 3 and the connecting plate 5, A plate 7 a is provided so as to straddle the intermediate plate 3 and the connecting plate 5.
That is, the intermediate plate 3 and the connecting plate 5 are sandwiched between the outer plate 7a and the outer plate 7b.
An elastic body 11 is provided on the upper surface of the outer plate 7a.

As shown in FIG. 2, a long hole 9 is provided in the longitudinal direction of the intermediate plate 3, and a bolt 13 is provided through the elastic body 11, the outer plate 7a, the long hole 9 and the outer plate 7b. ing.
A nut 15 is provided at one end of the bolt 13.

  Bolts 17a and 17b are provided through the outer plate 7a, the connecting plate 5 and the outer plate 7b, and nuts 19a and 19b are provided at one ends of the bolts 17a and 17b.

The intermediate plate 3 is movable in the B direction and the C direction in FIG. 1, and the friction damper 1 operates as a damper by a friction force generated between the intermediate plate 3 and the outer plate 7a and the outer plate 7b. .
However, since the bolt 13 passes through the elongated hole 9, the movement of the intermediate plate 3 is restrained by the bolt 13.
Further, the frictional force generated between the intermediate plate 3 and the outer plate 7 a and the outer plate 7 b can be adjusted by adjusting the tightening force of the bolt 13.

  Steel is used as the material of the intermediate plate 3, the connecting plate 5, the outer plate 7a, the outer plate 7b, the bolt 13, the nut 15, the bolt 17a, and the 17b nuts 19a and 19b, but the intermediate plate 3, the outer plate 7a, and the outer plate. 7b may use aluminum, lead or the like in order to adjust the frictional force.

The elastic body 11 is an elastic body for making the tightening force by the bolt 13 and the nut 15 constant, and when the plate thickness of the connecting plate 5, the outer plate 7a, and the outer plate 7b is changed due to wear and the tightening force is reduced. Swell to make the clamping force constant.
The elastic body 11 is a disc spring or the like.

The intermediate plate 3 and the connecting plate 5 are connected to a framework structure part of a building, a brace (muscle difference) or the like via a connection plate or the like.
When the building vibrates due to wind or earthquake, the energy applied to the friction damper 1 is converted into thermal energy by the friction force generated between the middle plate 3 of the friction damper 1 and the outer plate 7a and the outer plate 7b. The friction damper 1 absorbs vibration energy and reduces the vibration of the building.

Next, the structure of the friction surfaces of the intermediate plate 3, the outer plate 7a, and the outer plate 7b will be described in detail.
4 is a view taken in the direction of arrow A2 in FIG. 1, and FIG. 5 is a perspective view of the intermediate plate 3, the outer plate 7a, and the outer plate 7b.

  As shown in FIGS. 4 and 5, triangular grooves 23a, 23b, 25a, and 25b are provided on both surfaces of the intermediate plate 3, and triangular convex portions 21a and 21b are formed on the lower surface of the outer plate 7a. Is provided. Triangular protrusions 27a and 27b are provided on the upper surface of the outer plate 7b.

  The outer plate 7a and the intermediate plate 3 are provided so that the convex portions 21a and 21b and the groove portions 23a and 23b are in sliding contact, and the outer plate 7b and the intermediate plate 3 are in contact with the convex portions 27a and 27b and the groove portions 25a and 25b. Is provided.

  That is, when the intermediate plate 3 moves between the outer plate 7a and the outer plate 7b in the direction B or C in FIG. 1, a frictional force is generated between the convex portions 21a, 21b and the groove portions 23a, 23b, and the convex portions 27a, 27b. A frictional force is generated between the groove portions 25a and 25b.

  Next, the frictional force generated between the convex part 21a and the groove part 23a will be described with reference to FIGS. FIG. 6 is a detailed view of the vicinity of the groove 23a of the intermediate plate 3 and the convex portion 21a of the outer plate 7a. FIG. 7 is a diagram showing the relationship between the angle (2θ) and the apparent friction coefficient (F / C). .

As shown in FIG. 6, the bolts 13 fasten the intermediate plate 3, the outer plate 7 a, and the outer plate 7 b, thereby generating vertical drag forces 31 a and 31 b between the convex portion 21 a and the groove portion 23 a. When the vertical drag forces 31a and 31b are N and the angle 35 of the groove 23a is θ, the relationship between the pressing force C between the intermediate plate 3 and the outer plate 7a is expressed by the following equation.
C = 2N · sinθ

Accordingly, when the frictional force is F, the apparent friction coefficient μ between the intermediate plate 3 and the outer plate 7a is expressed by the following equation.
μ = F / C = F / (2N · sin θ)

μ (F / C) increases as θ decreases. For example, as shown in FIG. 7, when θ = 30 °, it is 2 in comparison with the case of sliding on a plane (when 2θ = 180 °). Double the value.
Therefore, the apparent friction coefficient can be increased without changing the material of the intermediate plate 3, the outer plate 7a, and the outer plate 7b and the bolt tightening force by forming the sliding surface inclination angle θ small. Can do.

  The apparent frictional force generated between the convex portion 21b and the groove portion 23b, and between the convex portions 27a and 27b and the groove portions 25a and 25b is the same as that of the convex portion 21a and the groove portion 23a, and thus the description thereof is omitted.

By the way, the shape of groove part 23a, 23b, 25a, 25b, convex part 21a, 21b, 27a, 27b is not restricted to a triangular shape.
8-10 is a modification of the convex part 21a and the groove part 23a. In addition, since the convex part 21b and the groove part 23b, the convex parts 27a and 27b, and the groove parts 25a and 25b are the same as that of the convex part 21a and the groove part 23a, description is abbreviate | omitted.

As shown in FIG. 8, a trapezoidal (polygonal) convex portion 41 and a trapezoidal (polygonal) groove 43 may be provided.
Moreover, as shown in FIG. 9, you may provide the circular-arc-shaped convex part 41a and the circular-arc-shaped groove part 43a.

  Furthermore, the shape of the convex portion and the groove portion is not necessarily the same. For example, as shown in FIG. 10, an arc-shaped convex portion 41b and a triangular groove portion 43b may be provided.

  Thus, according to the present embodiment, triangular grooves 23a, 23b, 25a, 25b, triangular convex portions 21a, 21b, and the like are formed on the surfaces of the middle plate 3, outer plate 7a, and outer plate 7b of the friction damper 1. 27a and 27b are provided, and the apparent friction coefficient can be increased by inclining the sliding surfaces of the grooves and the protrusions. Therefore, a large frictional force can be easily obtained at a low cost.

  As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

For example, in the present embodiment, the convex portions 21a, 21b, 27a, and 27b are continuously provided on the surfaces of the outer plate 7a and the outer plate 7b, but may be provided intermittently.
In the present embodiment, the cross-sectional shapes of the convex portion and the groove portion have been described as being symmetric, but they are not necessarily symmetric and may be asymmetric.

The perspective view which shows the friction damper 1 Sectional view of FIG. A1 direction arrow view of FIG. A2 direction arrow view of FIG. Perspective view of middle plate 3, outer plate 7a, outer plate 7b Detailed view of the vicinity of the groove 23a of the intermediate plate 3 and the convex portion 21a of the outer plate 7a The figure which shows the relationship between an angle (2 (theta)) and an apparent friction coefficient (F / C). Modified examples of the convex portion 21a and the groove portion 23a Modified examples of the convex portion 21a and the groove portion 23a Modified examples of the convex portion 21a and the groove portion 23a

Explanation of symbols

1 ………… Friction damper 3 ………… Middle plate 5 ………… Connecting plate 7a ………… Outer plate 9b ……… Outer plate 11 ……… Elastic body 13 ………… Bolt 15 ……… Nut 17a …… Bolt 19a …… Nut 20a …… Steel plate 21a …… Convex portion 22a …… Rubber 23a …… Groove portion 25a …… Groove portion 27a …… Convex portion

Claims (2)

A plurality of plate members slidably provided with each other;
Pressing means for pressing the plurality of plate members;
Comprising
The first plate member of said plurality of plate member has a convex portion and / or grooves on one side, the second plate member has a groove and / or convex portions on one surface,
The first plate member and the second plate member face each other, and the convex portion and / or groove portion of the first plate member and the groove portion and / or convex portion of the second plate member are in sliding contact. Is possible,
The sliding surface on which the convex portion and the groove portion are in sliding contact is provided inclined with respect to a plane formed by the sliding direction and the pressing direction,
A pair of the first plate members are configured to sandwich the second plate member, and a long hole is provided in the longitudinal direction of the second plate member,
The pressing means includes an elastic body provided on an upper surface of the first plate member, a bolt provided through the elastic body, the elongated hole, and the pair of first plate members, and one end of the bolt. It is made up of nuts provided,
Friction damper, wherein the convex portions and have rows of energy absorbed by the friction during sliding of the groove, it is possible to adjust the frictional force by adjusting the tightening force of the bolt. The friction damper according to claim 1, wherein a cross-sectional shape of a cross section perpendicular to the sliding direction of the convex portion or the groove portion is a triangle, a trapezoidal shape, other polygonal shapes, or a substantially circular shape.

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