JP3165900B2 - Variable damping mass damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable damping mass damper capable of damping a structure and changing its damping characteristic.

[0002]

2. Description of the Related Art Conventionally, as a mass damper for damping a structure, a laminated rubber having one end fixed to an installation portion, a weight portion fixed to the other end of the laminated rubber, and one end fixed to an installation portion. And a ball screw that is screwed to the other end of the reaction table along the surface direction of the laminated rubber and that is rotatably supported by the weight section. There is a tuned mass damper or an active mass damper that applies a driving force to the tuned mass damper. In these mass dampers, the natural period, the damping constant, and the like of the device are set so that the vibration of the structure can be effectively reduced.

[0003]

However, in general, the predominant vibration period of a structure changes depending on the age of the structure, the amplitude of the structure, the wind direction, and the like. It is necessary to change the natural period and the attenuation constant of the device in accordance with the situation. Changing the natural period and damping constant of a large mass damper is generally troublesome. Also, a variable damping mass damper that further enhances the vibration damping effect of a structure by changing the damping constant of the mass damper in real time in accordance with vibration has been proposed. Because of the large size, such a variable damping mass damper generally becomes a large-sized device, and the configuration of the device becomes complicated.

An object of the present invention is to provide a variable damping mass damper for a large stroke which can be realized with a compact and simple configuration.

[0005]

To achieve the above object, a variable damping mass damper according to the present invention comprises a laminated rubber having one end fixed to an installation portion and a weight portion fixed to the other end of the laminated rubber. A reaction table having one end fixed to the installation portion, and screwed to the other end of the reaction table along the surface direction of the laminated rubber and rotatably supported by the weight portion. A ball screw fixed to the weight portion, wherein the ball screw is inserted and an electrode is provided on the inside, and an electrode is fixed on the ball screw inside the casing and an electrode is provided on the outside. And an electrorheological fluid whose viscosity is controlled by an applied voltage is sealed in the casing.

[0006]

According to the variable damping mass damper of the present invention, when the weight portion oscillates with respect to the installation portion, the laminated rubber is deformed, and the ball screw screwed to the reaction force table rotates while the ball screw rotates against the reaction force table. The rotating member moves together with the weight part, and the rotation causes the rotating member fixed to the ball screw to rotate in the casing fixed to the weight part. here,
Since the electrorheological fluid is sealed in the casing,
Rotational resistance corresponding to the viscosity of the electrorheological fluid is applied to the rotating member and the ball screw. Therefore, the voltage applied between the electrode provided inside the casing and the electrode provided outside the rotating member, that is, electric voltage By changing the voltage applied to the viscous fluid, the rotational resistance applied to the ball screw, that is, the damping constant and the natural period of the variable damping mass damper change. Therefore, the damping constant and the natural period can be made variable without increasing the size of the device and without employing a complicated configuration.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A variable damping mass damper according to one embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a variable damping mass damper according to the present embodiment. The variable damping mass damper includes a plurality of laminated rubbers 3 each having one end fixedly installed at a predetermined position on an installation portion (usually, an upper portion of a structure) 2. ,
On the other end side of the plurality of laminated rubbers 3, for example, a weight portion 4 having each corner fixedly supported is provided. A concave portion 5 which is recessed one step from the upper surface side is formed in an intermediate predetermined range of the weight portion 4, and a through hole 6 penetrating vertically is formed in the intermediate predetermined range of the concave portion 5.

A reaction table 7 is installed on the installation section 2 at a predetermined position between the laminated rubbers 3. The reaction table 7 is mounted on the installation section 2.
, And is mainly composed of a fixing portion 8 lower than the laminated rubber 3 and a projecting portion 9 projecting upward from the fixing portion 8 so as to pass through the through hole 6. The upper end position of the protruding portion 9 is lower than the upper end position of the weight portion 4 by a predetermined amount, and the through hole 6 is a reaction force table even when the weight portion 4 vibrates to the maximum with respect to the installation portion 2. 7 is set so as not to interfere.

A ball screw 10 is provided on the upper surface of the concave portion 5 of the weight portion 4 so as to extend in the surface direction of the laminated rubber 3, that is, in the horizontal direction. 9 is screwed into an internal screw (not shown) provided in the apparatus. Here, in this embodiment, the ball screw 1
Both ends of the zero are rotatably supported by the damping device 11.

As shown in FIGS. 2 and 3, the damping device 11 has a casing 12 having a substantially cylindrical shape with both ends closed and fixed to the upper surface of the concave portion 5.
A support hole 14 is formed in the closed portion 13 at both ends of the casing 12, and the ball screw 10 is rotatably supported in the support hole 14 in a state where movement in the axial direction is restricted. An electrode 15 that can be energized from the outside is fixed to the entire inner periphery of the casing 12. Although not shown, a seal structure is adopted in the vicinity of the support hole 14 where the ball screw 10 is inserted to prevent the inside and the outside of the casing 12 from communicating with each other through the support hole 14. ing.

A columnar rotating member 16 is fixed to the ball screw 10 inserted into the casing 12.
7 is fixed to the entire circumference. Here, this rotating member 16
A constant gap is provided around the entire circumference between the electrode 17 of the casing 12 and the electrode 15 of the casing 12, and a constant gap is also formed between both end faces of the rotating member 16 and both inner end faces of the casing 12. ing. An electrorheological fluid 18 whose viscosity can be controlled by changing the applied voltage (that is, electric field strength) is sealed in the gap between the casing 12, the rotating member 16 and the ball screw 10. The electrodes 15 and 17 are subjected to a predetermined insulating treatment so as not to conduct electricity except through the electrorheological fluid 18.

According to the variable damping mass damper of this embodiment having the above-described configuration, when the weight portion 4 vibrates with respect to the installation portion 2, the laminated rubber 3 is deformed and the reaction force is increased as shown in FIG. The ball screw 10 screwed to the base 7 moves together with the weight part 4 with respect to the reaction force base 7 while rotating, and the rotation of the ball screw 10 causes the ball screw 10 to rotate.
The rotation member 16 of the damping device 11 fixed to the weight unit 4 rotates in the casing 12 of the damping device 11 fixed to the weight portion 4. Here, since the electrorheological fluid 18 is sealed in the casing 12, a rotation resistance corresponding to the viscosity of the electrorheological fluid 18 is applied to the rotating member 16 and the ball screw 10. By changing the voltage applied between the electrode 15 provided on the rotating member 16 and the electrode 17 provided on the outside of the rotating member 16, that is, the voltage applied to the electrorheological fluid 18, the rotation resistance applied to the ball screw 10, that is, the damping device 11 The damping constant will change. Therefore, the attenuation constant and the natural period can be made variable with a compact and simple configuration. In addition, the damping device 11 includes the ball screw 10
Because it is used for the rotating part of the above, any stroke in the translation direction is possible.

Although not shown, a sensor for detecting a vibration state of the weight portion 4 with respect to the installation portion 2 and an optimum damping constant based on information from the sensor are used to determine the both electrodes 1.
By providing a control device for controlling the voltage applied between 5, 17 and 17, the performance as a semi-active damper that controls the natural period and damping constant of the variable damping mass damper in real time according to the vibration state of the structure is exhibited. Will be. Moreover, since the equivalent viscosity of the electrorheological fluid 18 changes instantaneously when the electric field strength changes, there is no response delay or the like.

When the casing 12, the ball screw 10 and the rotating member 16 are formed of a conductive material, it is not necessary to fix electrodes to each other, and a voltage may be applied directly to the casing 12 and the ball screw 10 ( In this case, the casing 12 and the rotating member 16 become electrodes.)
Also in this case, predetermined insulation treatment is performed so that the casing 12, the ball screw 10, and the rotating member 16 do not conduct electricity except through the electrorheological fluid 18. Also,
When the resistance of the electrorheological fluid is increased, the rotating member is fixed to the ball screw 10 as a plurality of plates made of a conductive material, and the inside of the casing 12 is made of a conductive material alternately arranged with the plate of the rotating member. It is also possible to fix a plurality of such plates.

It is also possible to control the damping characteristics by providing the ball screw 10 and the damping device 11 not only in one direction of vibration but also in multiple directions (for example, two orthogonal directions).

In addition, it is possible to provide the damping device 11 at only one end of the ball screw 10 instead of at both ends. Apart from supporting the ball screw 10 on the weight portion 4, the damping device 11 may interfere with the reaction table 7. It is also possible to separately provide the damping device 11 at a position where no noise occurs.

Further, as shown in FIG.
A motor 19 is connected to one end of the motor, and a vibration state is determined by a control device (not shown) based on a signal from a sensor (not shown) for detecting vibration, and the motor 19 is driven in accordance with the vibration state, thereby actively controlling the motor 19. It is also possible to use an active variable damping mass damper that vibrates.

A calculation example using the variable damping mass damper of the above embodiment will be described below. First, assuming that the weight of the weight part 4 is 100 tons, the cycle of the apparatus is 4 sec, and the maximum damping constant is h = 0.2, the maximum damping coefficient c = 2mhω = 2 × 100/980 × 0.2 × 2 × π × 1 /4=0.064 [ton / cm / sec] Assuming that the maximum stroke of the variable damping mass damper is 1 m, the maximum damping force F = cv _max = 0.064 × 100 × 2 × π
× 1/4 = 10.1 [tonf] The pitch 8 cm was used as the ball screw 10 and the efficiency was 1.0.
Then, the required torque T = p / 2π × F = 8 / 2π × 10.1 = 12.9 [tonf · cm] Assuming that the resistance force of the electrorheological fluid 18 acts along the circumference of a diameter of 50 cm, The sum of the forces along the circumference Q = 12.9 / 50 ≒ 0.26 [tonf], and if two damping devices 11 are used, it will be only about half of this. Of course, a smaller and smaller mass damper requires less damping force.

[0019]

As described above in detail, according to the variable damping mass damper of the present invention, since the rotation resistance corresponding to the viscosity of the electrorheological fluid is applied to the rotating member and the ball screw, it is provided inside the casing. By changing the voltage applied between the electrode and the electrode provided outside the rotating member, that is, the voltage applied to the electrorheological fluid, the rotation resistance applied to the ball screw, that is, the damping constant and the natural period of the variable damping mass damper are changed. become. Therefore,
The variable damping constant and natural period can be realized with a compact and simple configuration.

[Brief description of the drawings]

FIG. 1 is a front view schematically showing an overall configuration of a variable damping mass damper according to one embodiment of the present invention.

FIG. 2 is a front sectional view schematically illustrating a damping device of a variable damping mass damper according to an embodiment of the present invention.

FIG. 3 is a side sectional view schematically illustrating a damping device of a variable damping mass damper according to an embodiment of the present invention.

FIG. 4 is a front view schematically showing a state of a variable damping mass damper according to an embodiment of the present invention when vibrating.

FIG. 5 is a front view schematically showing an entire configuration of a variable damping mass damper according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Variable damping mass damper 2 Installation part 3 Laminated rubber 4 Weight part 7 Reaction table 10 Ball screw 12 Casing 15, 17 Electrode 16 Rotating member 18 Electro-rheological fluid

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Fumie Ishikawa 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Yoshihiro Kurita 1-2-2 Shibaura, Minato-ku, Tokyo No. 3 Inside Shimizu Corporation (72) Inventor Shoji Hayashi 1-3-2 Shibaura, Minato-ku, Tokyo Inside Shimizu Corporation (56) Reference JP-A-60-57029 (JP, A) Kaihei 4-237778 (JP, A) JP-A 64-6765 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E04H 9/02 341 F16F 9/12 F16F 9/53 F16F 15/02-15/04

Claims (1)

(57) [Claims] 1. A laminated rubber having one end fixed to an installation portion, a weight portion fixed to the other end of the laminated rubber, a reaction table having one end fixed to the installation portion, A mass damper having a ball screw screwed to the other end side so as to extend along the surface direction of the laminated rubber and rotatably supported by the weight portion, wherein the ball screw is fixed to the weight portion and inserted. Together with a casing provided with electrodes on the inside, and a rotating member fixed to the ball screw inside the casing and provided with electrodes on the outside, and inside the casing,
A variable damping mass damper characterized by enclosing an electrorheological fluid whose viscosity is controlled by an applied voltage.