JPH02248581A - Variable damper device for vibration-proof structure - Google Patents

Abstract

PURPOSE:To secure safeness of a variable damper device as well as reduce the amount of response of structure by permitting the combined evaluation of the resonance and damping property of the structure by a method in which damping coefficients are made variable for the closing and opening cases of a great flow-switching valve. CONSTITUTION:Oil-pressure chambers 5 are provided on the left and right sides of a piston 3 reciprocally moving in a cylinder 2. The piston 3 is fixed or made movable by closing or opening a great capacity switching valve 10. A shut-off valve 11 is also provided on the back pressure port 14 side of the valve 10 to allow a great volume of pressure oil to flow to the valve 10 at high speeds or to interrupt in instantly. When the valve 10 is closed, a bypass thought which pressure oil is allowed to flow under a throttled condition is provided. Orifices 15 and 16 are adjusted to set up the damping coefficient to a variable or optional value when closing or opening the valve 10.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention connects the frame body of a structure and a variable rigidity element, or variable rigidity elements provided within the frame, and changes the connection state and damping coefficient. In particular, the present invention relates to a variable damping device for protecting a structure from vibration disturbances.

[Prior Art] The applicant incorporates variable rigidity elements in the form of places, walls, etc. into the column-beam frame of a structure, and attempts to improve the rigidity of the variable rigidity elements themselves.
Alternatively, the state of connection between the frame body and the variable rigidity element can be made variable, and the characteristics of the external vibrational force such as earthquakes and wind are analyzed using a computer, and the rigidity of the structure is changed to make it non-resonant. Various active restraint systems and variable rigidity structures have been proposed to ensure the safety of objects (for example, JP-A-62-268479, JP-A-63-11477).
No. 0, JP-A-63-114771, etc.).

[Problem to be solved by the invention]

By the way, conventional active restraint systems mainly focus on the relationship between the predominant period of seismic motion and the natural frequency of the structure (usually, the first natural frequency is often the problem). By actively shifting the natural frequency of the structure with respect to the period, we aim to avoid reduction in resonance and reduce the amount of response.

However, especially in the case of earthquake motion, since it is an unsteady vibration, control may not always be optimal, for example, when the dominant period is unclear or there are multiple dominant periods.

The present invention provides control that comprehensively evaluates the resonance and damping properties of a structure by changing the damping coefficient of the device when interposed between the frame body and variable stiffness elements, or between variable stiffness elements. The purpose is to provide a variable damping device that makes it possible to reduce the amount of response of a structure, ensure the safety of the structure, and realize a comfortable living space.

[Means to solve the problem]

The variable attenuation device of the present invention will be explained below using the reference numerals corresponding to the embodiments.

As shown in FIG. 1, the main body of the variable damping device 1 of the present invention is provided with hydraulic chambers 5 on the left and right sides of a piston 3 of the double Rondo type that reciprocates within a cylinder 2, and the pressure inside these left and right hydraulic chambers 5 is The piston 3 is configured to be fixed or to be movable left and right by closing or allowing the oil to flow using the large flow rate switching valve 10.

One of the cylinder 2 and the rod 4 is connected to the frame body and the variable rigidity element or one of the variable rigidity elements of the structure, and the other is connected to the frame body and the other of the variable rigidity element or the variable rigidity elements.

The left and right hydraulic chambers 5 are respectively provided with an outflow prevention check valve 6 that prevents pressure oil from flowing out from the hydraulic chamber 5 and an inflow prevention check valve 7 that prevents pressure oil from flowing into the hydraulic chamber 5. An inflow passage 8 that connects the left and right outflow prevention check valves 6 and an outflow passage 9 that connects the left and right inflow prevention check valves 7 are provided along the cylinder 2 body.

At the connecting position of these inflow channel 8 and outflow channel 9,
A large flow rate switching valve 10 is provided.

The large flow switching valve 10 has, for example, an inlet port 12 and an outlet port 13 at one end of the valve body, and a back pressure port 1 at the other end.
4, by providing a shutoff valve 11 in the flow path on the back pressure port 14 side to prevent pressure oil from flowing out to the back pressure port 14 side, a large volume of pressure oil can flow at high speed,
It can also be shut off instantly.

The present invention further includes a bypass passage for allowing the pressure oil to flow in a restricted state even when the large flow rate switching valve 10 is closed, and by opening and closing the large flow rate switching valve 10,
The first damping coefficient c when it is in the open state and the second damping coefficient C when it is in the closed state! The damping coefficient is made variable between (>CI).

More specifically, for example, by providing the first orifice 15 in the inflow channel 8 or the outflow channel 9 and designing the opening degree of this orifice 15, the large flow rate switching valve 1
By providing a predetermined first damping coefficient when 0 is the open state, and by providing an orifice in the bypass flow path for the above-mentioned large flow switching valve 10, or by designing the bypass flow path itself as an orifice 16, It is possible to provide a predetermined second damping coefficient 02 when the large flow switching valve 10 is in the closed state. Figure 3 conceptually shows this.

[For production]

The variable damping device of the present invention is a double rod cylinder type, and is provided with two flow paths, an inflow flow path 8 and an outflow flow path 9, check valves 6 and 7, and a large flow switching valve 10 along the cylinder 2. As a result, the length of the passage can be shortened, the area of the passage can be increased, and the resistance of the passage can be reduced, so that a large amount of pressure oil can flow at high speed and can be shut off instantaneously. Also,
By using the back pressure type large flow switching valve 10, it can be opened and closed instantaneously, and in combination with the above-mentioned structure, the response speed can be extremely fast.

Next, the operating state of the variable damping device 1 of the present invention will be explained.

(1) Large flow switching valve open When the shutoff valve 11 is open, the piston 3 in Fig.
, the pressure oil in the left hydraulic chamber 5 passes through the inflow prevention check valve 7 and the outflow channel 9 and pushes up the large flow rate switching valve 10.

Since the left outflow prevention check valve 6 and the right inflow prevention check valve 7 are closed by pressure oil, the large flow switching valve is connected via the inflow channel 8 and the right outflow prevention check valve 6. Pressure oil from 10 flows. As a result, pressure oil flows from the left hydraulic chamber 5 to the right hydraulic chamber 5, and the piston 3 moves leftward due to external force.

At this time, the orifice 15 of the outflow channel 9 functions and provides resistance to the flow of pressure oil. Therefore, by designing the opening degree of this orifice 15, a predetermined small damping coefficient 01 close to the free state is given to the device 1 of the present invention.

Even when the piston 3 moves to the right, the actuation is symmetrical to this, and the piston 3 moves to the left due to external force.

(2) Close the large flow switching valve When the shutoff valve 11 is closed and an external force is applied to the piston 3 in the left direction, the oil pressure up to the large flow switching valve 1o will rise, pushing up the large flow switching valve 1o. However, since the hydraulic pressure at the back pressure port 14 is received by the shutoff valve 11, the large flow switching valve 10 is also fixed in a closed state, and movement of the piston 3 is prevented. However, as described above, since the orifice 16 is formed in the bypass for the large flow rate switching valve 10, the pressure oil flows through the orifice 16 without encountering resistance.

In this way, when the large flow switching valve 10 is in the closed state, a damping coefficient 02 that is larger and nearly fixed is provided than when it is in the open state.

The same applies when an external force is applied to the piston 3 in the right direction.

When the above variable damping device 1 using hydraulic pressure is installed between the frame body and the variable rigidity element, the damping force on the frame body and body is a resistance force approximately proportional to the square of the relative speed between the cylinder 2 and the piston 3. (P=cv"), and the frame body exhibits different characteristics depending on the magnitude of vibration (for example, amplitude).

〔Example〕

The present invention will be described below based on an illustrated embodiment.

FIG. 1 shows the specific structure of the variable damping device 1 of the present invention.The main body of the device 1 includes a double-rond type piston 3 in a cylinder 2 so that its piston rod 4 protrudes from both ends. It is slidably inserted. piston 3
The hydraulic chambers 5 formed on the left and right sides each include an outflow prevention check valve 6 that prevents pressure oil from flowing out of the hydraulic chamber 5, and an inflow prevention check valve that prevents pressure oil from flowing into the hydraulic chamber 5. A valve 7 is provided.

The check valve 6.7 has a structure in which, for example, a ring-shaped valve body is biased by a spring to allow pressure oil to flow in only one direction. An outflow passage 9 connecting the passage 8 and the left and right inflow prevention check valves 7 is provided, and these are connected via a large flow rate switching valve 10 to allow the left and right hydraulic chambers 5 to communicate with each other.

In this embodiment, an inlet port 12 and an outlet port 13 are formed at one end of the large flow switching valve 10, and a back pressure port 14 is formed at the other end, and a shutoff is provided in the flow path on the back pressure port 14 side. A valve 11 is provided. This shutoff valve 11 can be switched between two positions, open and closed, using a solenoid 17.

Further, an orifice 15 is provided in the inflow channel 9, thereby giving the device a small damping coefficient Ct.

Further, an orifice 16 is provided in the form of a bypass of the large flow rate switching valve 10, thereby providing a large damping coefficient 02 when the large flow rate switching valve 10 is in the closed state.

Further, as shown in the figure, the cylinder 2 has an inflow channel 8.
Install the accumulator 18 that communicates with the this is,
This is an oil reservoir that pressurizes the pressure oil in the cylinder 2 to (atmospheric pressure + α), and supplies oil due to leakage, prevents air bubbles from entering, compresses oil when locked, and replenishes volume changes due to temperature changes.

Next, a specific restraint system using the variable damping device 1 of the present invention will be explained.

FIG. 2 shows an outline of the configuration of an active braking system using the variable damping device 1 of the present invention, which includes a frame body 31 consisting of columns 33 and beams 34, and a structure built into the frame body 31 of each layer. The variable damping device 1 is interposed between the inverted square-shaped place 35 as a variable rigidity element. The input seismic motion and the response (amplitude, velocity, acceleration) of the structure are sensed by the input sensor 36 and response sensor 37, respectively, and the computer 38 calculates the damping coefficient of the variable damping device 1 according to the seismic motion characteristics (predominant period) and the response state. and issue control commands. FIG. 6 shows the flow at that time.

As mentioned above, in the variable damping device 1 shown in FIG. 1, the damping force on the frame body is given as a resistance force approximately proportional to the square of the relative speed between the cylinder 1 and the piston 3, and the structure characteristics in this case are shown in FIG. 4. and as shown in Figure 5,
In the figure, the solid line indicates when the amplitude is large, and the broken line indicates when the amplitude is small. That is, a frame using a lock cylinder exhibits different characteristics depending on the magnitude (eg, amplitude) of vibration. The graphs in Figures 4 and 5 show two types of vibration levels (interlayer amplitude ±
0.5cm and ±3.0cm), and shows the value of the damping coefficient C of the lock cylinder that maximizes the damping constant of the frame (the damping coefficient Cot that maximizes the damping constant at a large vibration level, The natural period of the frame also changes near the damping coefficient C6, where the damping constant becomes maximum at a small vibration level.

Suppose that the damping coefficient at the upper limit vibration level to be controlled is the above-mentioned C01, and the damping coefficient at the lower limit vibration level to be controlled is the above-mentioned Cot, and if periodic changes are always possible within that range, As is clear from FIG. 4, the above-mentioned first damping coefficient c and second damping coefficient 02 are respectively expressed as Cr <Col5Cz >Coz (
1), and as is clear from FIG. 5, values that do not deviate significantly from C01% cot are preferred.

Table 1 shows examples of the damping constant of the structure and the primary natural period of the bridge for the two types of damping coefficients C6 and C2 that have been set.

However, the selection of Cr and Ct varies depending on the range of vibration levels to be controlled, and if it is acceptable to limit the range in which periodic variation is possible, the selection of Cr and Ct is not necessarily limited to the range in (1) above. .

As shown in the flowchart in Figure 6, the vibration external force input to the structure is detected by sensors inside or outside the structure, and the dominant period and other frequency characteristics are analyzed by the frequency characteristic analysis means in the computer program. Ru. On the other hand, the actual response amount of the structure or frame body is sensed by a sensor such as an accelerometer, speedometer, or displacement meter as a response amount measuring means, and the damping coefficient selection means in the computer program is used to determine the frequency characteristics and response amount. By evaluating the non-resonance property and the damping property of the frame body and considering them in a combined manner, one of the two types of damping coefficients CI and C2 that reduces the response of the structure is selected. In other words, based on the obtained frequency characteristics and response amount, cases where the dominant period is unclear and non-resonance cannot be achieved, or cases where damping control is more effective than non-resonance due to the distribution of periodic components such as earthquake motion, are determined based on the obtained frequency characteristics and response amount. The attenuation coefficient can be selected using a computer. Note that the natural period of the frame body or structure can be either short or long depending on the vibration level by selecting the damping coefficient.

Therefore, the selection of the natural period for non-resonance is also performed by selecting the damping coefficient depending on the vibration level at that time. The selected damping coefficient is realized by applying a control command to the above-mentioned coupling device from the control command generating means.

More specifically, control is performed as follows.

■ Set the vibration level to control. For example, the amount of deformation between the eyebrows is ±0.5 cm to ±3.0 cm, and the speed is 1 to 25 cm.
kins (cm/5ec) etc.

■ Understand the structure characteristics at the upper and lower limits of the set vibration level. For example, changes in the period of the frame body and the damping constant due to the damping coefficient of the variable damping device.

(2) Select damping coefficients C1s and C11 of a variable damping device that can reliably change the cycle at a set vibration level and add as large a damping effect as possible to the frame, and select one of them by a control command.

■ By looking at the response of the structure and evaluating its damping properties (feedback control), and by looking at the characteristics of the seismic motion (predominant period) and evaluating its non-resonance (feedforward control),
Composite control becomes possible.

■ When there is always small vibration (wind, small earthquake), the damping coefficient is set to 02, which produces the greatest damping effect at the small vibration level.

Table 2 summarizes, as a control example, the state of control when the seismic motion characteristics correspond to FIGS. 7(a) to (2). In addition, in FIGS. 7(a) to (9), the solid line is the response spectrum of the earthquake motion, the dashed line is the response value when damping coefficient C3 is selected, the broken line is the response value when damping coefficient 02 is selected,
A black circle indicates a response value with the selected damping coefficient, and a white circle indicates a response value with the other damping coefficient that was not selected.

Table 2 Figures 8 to 15 show variable damping devices for structural frames.
This figure shows an example of the application position.

In the example shown in FIG. 8, the variable damping device 1 is interposed between the columnar beam frame as the frame body 31 and the inverted V-shaped place 35 as the variable rigidity element.

In the example shown in FIG. 9, a variable damping device 1 is interposed between a column-beam frame as a frame body 31 and frames 41 erected or suspended from upper and lower beams 34, and moment resistance as a variable rigidity element is provided. This is the case when a frame is configured.

In the example shown in FIG. 10, a variable damping device 1 is interposed between the column-beam frame as the frame body 31 and the RC shear wall 42 as a variable rigidity element.

The example shown in FIG. 11 is an example in which a variable damping device 1 is provided at the base of a seismic isolation structure in combination with a seismic isolation rubber 43 such as laminated rubber. playing a role. The variable stiffness element in this case can be considered the foundation of the structure.

In the example shown in FIG. 12, an X-shaped place 44 provided within the column-beam frame as the frame body 31 is used as a variable rigidity element, and the variable damping device 1 is interposed laterally (horizontal type) in the center of the X-shape.

The example in FIG. 13 is an example applied to the X-shaped place 45, similar to the example in FIG. 12, and while the example in FIG. It is installed vertically.

The example in FIG. 14 is similar to the example in FIG.
A variable damping device 1 is interposed between the two and is characterized in that the variable damping device 1 is provided above an opening 47 such as an entrance/exit.

In the example shown in FIG. 15, the variable damping device 1 is interposed in the center of the X-shaped place 48 in the large frame, and the middle large beam 4
9 and place 48 are separated.

〔Effect of the invention〕

As mentioned above, the variable rigidity device according to the present invention is a double-rond cylinder type, and the cylinder is equipped with two oil flow paths, a check valve, and a large flow rate switching valve, and also has a back pressure type large flow rate switching valve. Since the flow path is opened and closed, it is possible to flow a large flow of pressure oil at high speed or to instantly shut off a large flow of pressure oil, and it is also possible to turn on and off instantly with good response.

When applied to a variable damping/variable rigidity structure, the damping coefficient of the variable rigidity device is changed in response to external disturbances such as seismic motion input to the structure, providing damping performance and rigidity according to the characteristics of the structure. By doing so, it is possible to reduce the amount of response of the structure, ensure safety, and realize a comfortable living space.

[Brief explanation of drawings]

Fig. 1 is a hydraulic circuit diagram showing the basic structure of an embodiment of the variable damping device of the present invention, Fig. 2 is a schematic diagram of the configuration of an active braking system in an embodiment of the invention, and Fig. 3 is a hydraulic circuit diagram showing the basic structure of an embodiment of the variable damping device of the present invention. 4 and 5 are graphs for explaining the characteristics of the frame in an active braking system using the variable damping device of the present invention, and FIG. 6 is a diagram of the control in the embodiment. Flow chart, Fig. 7(a) to Fig. 7(
Graphs showing the relationship between seismic motion characteristics and response amounts for two types of attenuation coefficients in Examples, Figures 8 to 15
The figure is a schematic diagram showing an example of the application position of the variable damping device of the present invention to a structural frame. l...Variable damping device, 2...Cylinder 3...
Piston, 4... Rod, 5... Hydraulic chamber, 6...
Check valve for outflow prevention, 7... Check valve for inflow prevention, 8... Inflow channel, 9... Outflow channel, 10...
・Large flow rate switching valve, 11... Shutoff valve, 12.
... Inlet port, 13... Outlet port, 14... Back pressure port, 15... Orifice, 16... Orifice, 17... Solenoid, 18... Accumulator Figure 1, C Figure (a) (b) (d) Figure Figure (e) U, 4 1.0 Figure Figure

Claims (3)

[Claims] (1) A cylinder connected to the frame body of the structure and the variable stiffness element or one of the variable stiffness elements, and a cylinder connected to the frame body and the other of the variable stiffness element or the variable stiffness elements and reciprocated within the cylinder. a double rod type piston, a hydraulic chamber provided on both sides of the piston, a pair of check valves for preventing pressure oil from flowing out of both the hydraulic chambers, and a hydraulic chamber provided on both sides of the piston; a pair of inflow prevention check valves that prevent inflow; an inflow channel that connects both of the outflow prevention check valves; an outflow channel that connects both of the inflow prevention check valves; and the inflow channel. and a large flow switching valve provided at a connection position of the outflow flow path, and a bypass flow path for the large flow switching valve, and a first Variable damping for a vibration damping structure, characterized in that the damping coefficient is variable between the damping coefficient c_1 and the second damping coefficient c_2 (>c_1) when the large flow switching valve is in the closed state. Device. (2) The inflow channel or the outflow channel is provided with a first orifice that provides the first damping coefficient c_1 when the large flow switching valve is opened, and the bypass The variable damping device for a vibration damping structure according to claim 1, wherein the flow path constitutes a second orifice that provides the second damping coefficient c_2 when the large flow switching valve is in a closed state. (3) The large flow switching valve has an inlet port and an outlet port on one end of the valve body, a back pressure port on the other end, and a flow path on the back pressure port side. 3. The variable damping device for a seismic damping structure according to claim 1, further comprising a shutoff valve for preventing pressure oil from flowing out.