JPH094273A - Damping-coefficient automatic adjusting type earthquake damping device - Google Patents

Abstract

PURPOSE: To improve the safety and amenity of a building by a method wherein relative displacement between a cylinder and a piston for a variable damping device is amplified, a speed signal is differentiated and a pressure signal corresponding to acceleration working to a column-beam frame is obtained, an acceleration signal is integrated and the displacement of the column-beam frame is acquired and fed back to the variable damping device. CONSTITUTION: Displacement X2 corresponding to the speed of a piston 3 for a hydraulic cylinder type damping device is obtained in a governor section A by rotating a pinion 20 for the hydraulic cylinder type damping device. Air pressure P1 corresponding to acceleration (a) working to a column-beam frame is acquired by a differential operating section B by utilizing the displacement X2 . Displacement X3 and the displacement X4 of the column-beam frame are synthesized at a ratio, where an optimum damping coefficient is given, by a proportional operating section C continued to the differential operating section B by using the air pressure P1 . A valve-opening controller 28 is driven through a diaphragm valve 27 by a valve-opening controller operating section D, and oscillation frequency Wt is identified and controlled on the basis of formula Wt =|a/x|<1/2> from acceleration (a) and displacement (X) so that the hydraulic cylinder type damping device displays the optimum damping coefficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping coefficient adjusting type damping device for imparting a high damping property to the response of a structure to a vibration external force such as an earthquake or wind and reducing the vibration.

[0002]

2. Description of the Related Art A variable damping device for a seismic control structure is installed in a frame of a structure, and the damping coefficient of the device is actively changed according to the characteristics such as individual earthquakes and external wind forces. The damping resistance reduces the vibration of the structure, and the control means using a computer or the like can evaluate and control the damping property of the structure.

As such a variable damping device for a vibration control structure, there is, for example, the one described in JP-A-2-289769.

FIG. 2 is a diagram showing an example of such a variable damping device as a hydraulic circuit diagram. Hydraulic chambers 6 are provided on the left and right sides of a double rod type piston 3 that reciprocates in a cylinder 2, and the left and right sides of the hydraulic chambers 6 are provided. The piston 3 is fixed or movable left and right by closing and flowing the hydraulic pressure in the hydraulic chamber 6 with a valve.

Then, the cylinder 2 and the rod 4 are respectively connected to the columns of the structure, the beam frame main body, or the seismic resistant elements such as the brace and the seismic wall to provide damping resistance against the deformation of the columns and the beam frame.

The left and right hydraulic chambers 6 respectively include an outflow prevention check valve 8 for preventing the pressure oil from flowing out of the hydraulic chamber 6 and an inflow prevention check valve 9 for preventing the pressure oil from flowing into the hydraulic chamber 6.
Is provided for connecting the left and right outflow prevention check valves 8 to each other, and the left and right inflow prevention check valves 9
An outflow passage 11 for connecting the two is provided.

These inflow channel 10 and outflow channel 11
A flow rate control valve 12 is provided at the connecting position of, and the damping coefficient c of the variable damping device 1 can be adjusted by changing the opening degree of the flow rate control valve 12.

Further, in this example, the flow rate control valve 12 has a large flow rate switching valve 12a having an inlet port 15 and an outlet port 16 on one end side of the valve body and a back pressure port 17 on the other end side.
A shut-off valve 12b capable of controlling the outflow of pressure oil to the back pressure port 17, and in response to a command from the valve opening controller 28, the shut-off valve 12b opens and closes, and accordingly, the large flow rate switching valve. 12a operates, and the large flow rate switching valve 12
The opening degree of a and the damping coefficient c of the device according to the opening degree are adjusted and controlled.

That is, by adjusting the opening degree of the flow rate switching valve 12 and finely adjusting the connection state between the completely locked state and the completely free state, various damping coefficients c are given, and the damping coefficients c and According to the vibration state of the frame body, the natural period of the frame body and the damping constant h of the frame body at that time are given.

Further, the inflow passage 10 or the outflow passage 1
1 is provided with an accumulator 19 and the like for the purpose of compensating for volume change due to compression of hydraulic oil and temperature change.

[0011]

When the damping coefficient c of the variable damping device is changed to reduce the response of the building frame, various control laws using various parameters can be considered. With such changes, the natural frequency of each order of the column / beam structure and the entire building changes, the damping constant h also changes accordingly, and when the natural frequency of higher than 2nd order is predominant. There are various factors that complicate the rule.

On the other hand, it is possible to perform a complicated analysis by a computer based on a signal from a sensor or the like installed inside or outside the building or in a device section, but it is costly and the device is not required. Problems with the stability of the operation and control of are likely to occur.

The present invention relates to a hydraulic cylinder type damping device as disclosed in, for example, Japanese Patent Application Laid-Open No. 2-289769, which utilizes the relative movement between the cylinder and the piston due to swaying to open the valve. Provide a vibration control device that automatically adjusts.

Since all of the control is performed by pneumatic pressure in this device, it is not necessary to separately provide a special power source and sensor for control, and passively, without using energy from the other, a control close to that of an active vibration control device. Exerts a seismic effect.

[0015]

SUMMARY OF THE INVENTION The damping coefficient automatic adjustment type damping device of the present invention converts a hydraulic cylinder type damping device and a relative displacement speed of a piston with respect to a cylinder of the hydraulic cylinder type damping device into a rotational motion, and a piston. Governor for obtaining a displacement corresponding to the relative displacement speed of, a differential operation unit for obtaining an acceleration a acting on a column / beam frame based on the governor, and a variable damping device based on the acceleration a and displacement x using air pressure. It consists of a proportional operation part that determines the opening of the adjusting valve. The signal air pressure of the proportional operation unit drives the valve opening controller via the diaphragm valve to achieve the purpose.

Next, how these give the optimum damping coefficient will be described.

The optimum damping coefficient c _opt is expressed by the following equation.

[0018]

[Equation 1]

K _f = rigidity of column / beam structure only K _b = rigidity of seismic element only ω _t = vibration frequency of the entire column / beam structure including seismic element at a certain time As column / beam structure and seismic element were placed braces and variable damping device, high-rise building is complex stiffness K _c of the layer when subjected to vibration sinusoidal pressure of frequency fHz is expressed by the following equation.

[0020]

[Equation 2]

Here, ω = 2πf Here, the damping constant h of the layer can be expressed by the following equation.

[0022]

(Equation 3)

In order to maximize the real part of K _R = K _c and the imaginary part h of K _I = K _c , if dh / dc = 0,

[0024]

(Equation 4)

If the ratio of the frame rigidity K _f and the brace rigidity K _b , K _b / K _f = N, then the above equation is

[0026]

(Equation 5)

It can be expressed as Therefore, it is understood that c _opt that maximizes the damping constant h of the building is determined by K _f , K _b , and ω. Of these, K _f and K _b are determined by the specifications at the time of design, so it is sufficient if the vibration frequency ω (= 2πf) can be identified.

As a method of identifying ω, if the amplitude of the device section is x = Dsin ωt, the velocity is v = ωDco
Since s ωt and acceleration a = −ω ² Dsin ωt, ω can be identified by the following equation. If the identified ω is ω _t ,

[0029]

(Equation 6)

Therefore, according to the apparatus of the present invention, the acceleration a is calculated from the differential circuit in response to the change in the response of the building every moment.
Is calculated, and the opening controller is controlled by a command value obtained by combining it with the displacement x at a certain ratio, whereby the initial purpose of automatically adjusting the damping coefficient can be achieved.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The damping coefficient automatic adjustment type vibration damping device of the present invention will be described below with reference to the drawings.

FIG. 1 is one of the embodiments of the present invention. A rack 21 is attached to one end of a cylinder 2 of a hydraulic cylinder type damping device 1 as shown in FIG. 2, and a piston is engaged with the rack 21. A pinion 20 is provided on the rod 4, and a governor 23 is driven via a speed increasing gear 22. Originally, the rack 21 and the pinion 20 are attached in the horizontal direction of the cylinder 2, but in FIG. 1, the attachment direction of the rack 21 and the pinion 20 is shown rotated by 90 ° for easy understanding. So in reality the axis 20 'of the pinion 20 is vertical,
In the figure that meshes with the rack 21, the shaft 20 'is shown in a horizontal state. By rotating the pinion 20 of the hydraulic cylinder type damping device, a displacement x ₂ corresponding to the speed of the piston 3 of the hydraulic cylinder type damping device is obtained in the governor portion A. By utilizing the displacement x ₂ , the air pressure P ₁ corresponding to the acceleration a acting on the column / beam frame in the differential operation part B can be obtained. Using the air pressure P ₁ corresponding to the acceleration a, the differential operation unit B
The air pressure P ₂ is obtained as a result of combining the displacement x ₃ and the displacement x ₄ of the column / beam frame with the ratio that gives the optimum damping coefficient in the proportional operation part C continuous to At D, the pressure from the compressed air accumulator is used to drive the valve opening controller 28 via the diaphragm valve 27, and the hydraulic cylinder type damping device 1 automatically performs control such that the optimum damping coefficient c _opt is exerted. To do it.

[0033]

When the device of the present invention is used, the relative movement of the cylinder and the piston of the hydraulic cylinder type damping device is fed back as it is to control the hydraulic cylinder type damping device. When the optimum damping coefficient c _opt that maximizes the damping constant h by automatically obtaining the acceleration a and the displacement x corresponding to the vibration frequency ω _t at every moment is automatically obtained, and the vibration cycle of the building fluctuates, Even in situations where high-order vibrations are predominant, it is possible to maintain high damping and enhance the safety and comfort of the building.

[Brief description of drawings]

FIG. 1 is one of the embodiments of the present invention.

FIG. 2 is a diagram showing an example of a variable damping device as a hydraulic circuit diagram.

[Explanation of Codes] 1 ... Variable damping device, 2 ... Cylinder, 3 ... Piston, 4 ... Piston rod, 6 ... Hydraulic chamber, 8
... outflow prevention check valve, 9 ... inflow prevention check valve, 10 ... inflow passage, 11 ... outflow passage, 12 ... flow control valve, 15 ... inlet Port, 1
6 ... Exit port, 17 ... Back pressure port, 19 ...
・ Accumulator, 20 ・ ・ ・ Pinion, 20 '・ ・
・ Pinion shaft, 21 ・ ・ ・ Rack, 22 ・ ・ ・ Increasing gear, 23 ・ ・ ・ Governor, 24 ・ ・ ・ Bellows, 25 ・
..Nozzle, 26 ... Integral tank, 27 ... Daijifuramu valve, 28 ... Opening controller

Claims (1)

[Claims] 1. A column / beam frame of a structure, and a variable damping device provided in the column / beam frame, a means for amplifying relative displacement between a cylinder and a piston of the variable damping system, A differential operation unit that converts the amplified displacement velocity into an air pressure signal and differentiates the velocity signal to obtain a pressure signal corresponding to the acceleration a acting on the column / beam frame; and the column / beam by integrating the velocity signal. An integral operation unit for obtaining the displacement x of the frame is provided, and the following equation is calculated from the acceleration a and the displacement x. A damping coefficient automatic adjustment type damping device characterized in that the vibration frequency ω _t is identified based on the above, and is fed back to the variable damping device.