JP2004052959A - Hydraulic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic damper capable of exerting its damping performance sufficiently by shortening unloading time when a large scale external vibration force is generated and capable of making an impact sound by lengthening unloading time when a slight external vibration force is slightly generated. <P>SOLUTION: In the hydraulic damper 31 wherein a plurality of oil passages 5 passing between a pair of hydraulic chambers 4A and 4B, which are provided on both sides of the piston 3 in a hydraulic cylinder 2, are arranged in parallel, and opening and closing control valves V11 and V12 are provided in each of a plurality of the oil passages 5, detecting means 8 to 10 for detecting the pressure of the hydraulic chambers 4A and 4B and the displacement of the piston 3 respectively, a calculation means 27 for calculating the magnitude of external vibration force F based on the pressure and the displacement detected by the detecting means 8 to 10, and a control means 27 for adjusting and controlling unloading time based on the magnitude of the external vibration force F calculated by the calculation means 27 are provided. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hydraulic damper for attenuating a building shake caused by an external vibration force such as an earthquake or wind.
[0002]
[Prior art]
As a conventional hydraulic damper, for example, there is one shown in FIG. A conventional hydraulic damper 11 shown in FIG. 1 includes a pair of hydraulic chambers 4A and 4B provided on both sides of a piston 3 reciprocating in a hydraulic cylinder 2, and a flow path 5 connecting the two hydraulic chambers 4A and 4B. Opening / closing control valve V1 for switching the damping coefficient of the hydraulic damper 11 between the maximum value and the minimum value, a relief valve V2 for preventing the hydraulic damper 11 from being damaged due to a high pressure, and a throttle valve V3 operated at the time of a power failure. Are provided in the oil passage 5 in parallel with each other.
[0003]
A pressure gauge 8, 9 having a pressure detection unit attached to each of the two hydraulic chambers 4A, 4B, a displacement gauge 10 for measuring a relative displacement between the hydraulic cylinder 2 and the piston 3 from a displacement of the piston rod 6, Based on the pressures P ₁ and P _{2 of} the two hydraulic chambers 4A and 4B detected by the pressure gauges 8 and 9 and the relative displacement △ d detected by the displacement meter 10 according to a preset control procedure. A control circuit 17 for controlling the opening / closing operation of the opening / closing control valve V1 to constitute a closed control system.
[0004]
Such a conventional hydraulic damper 11 can reduce costs by reducing the number of parts by constructing a closed control system that does not require an external control command as described above, It has the advantage that the above man-hours can be reduced.
[0005]
The on-off control valve V1 is turned on and off when the power from the control circuit 17 is ON, and closed when the power from the control circuit 17 is OFF due to a power failure or the like. Has a fail-safe function of performing the reverse operation.
[0006]
That is, in the event that an external force due to an earthquake or the like cannot be generated and the on-off control valve V1 cannot be opened in the event of an abnormality where the power supply is turned off, the pair of hydraulic chambers 4A are opened by opening the on-off operation throttle valve V3. , 4B, and the function as a hydraulic damper can be maintained.
[0007]
The relief valve V2 is not controlled by the control circuit 17, and when the oil passage 5 or the hydraulic chamber 4A or 4B has a high pressure close to the strength limit that the oil valve 5 can withstand, the high pressure causes the hydraulic damper 11 The oil passage 5 and the hydraulic chambers 4A and 4B are opened to prevent rupture, and operate to release a part of the oil from the high-pressure oil passage 5 and the hydraulic chambers 4A and 4B to other places. Things.
[0008]
[Problems to be solved by the invention]
However, in such a conventional hydraulic damper 11, since the opening and closing of the on-off control valve V1 is simply controlled uniformly by the control circuit 17 according to a preset control procedure, the length of time for unloading the external vibration force is reduced. It cannot be adjusted according to the magnitude of the external vibration force.
[0009]
In addition, in such a conventional hydraulic damper, an impact sound (unloading sound) is generally generated when the external vibration force is unloaded. However, the impact sound becomes small when the unloading time of the external vibration force is long, It increases when the unloading time is short. On the other hand, when a large-scale vibration external force is generated, it is necessary to shorten the unloading time in order to exhibit sufficient damping performance.
[0010]
Therefore, when large-scale external vibration such as an earthquake occurs, priority should be given to damping performance to shorten the unloading time, and when a small external vibration due to wind or the like occurs, the impact sound should be reduced. It is desirable to extend the unloading time first. However, in the conventional hydraulic damper, the unloading time cannot be adjusted according to the generated external vibration force.
[0011]
Therefore, in view of the above problems, the present invention shortens the unloading time when a large-scale vibration external force is generated to sufficiently exhibit the damping performance, and gradually reduces the unloading time when a small vibration external force is generated. It is an object of the present invention to provide a hydraulic damper that can lengthen the load time and reduce the impact sound.
[0012]
[Differences from other conventional technologies]
In addition, as another conventional technique, there is a variable damping device for a vibration control structure as described in JP-A-2002-13310. Such a variable damping device is intended to solve the problem that the comfortability is impaired due to a slight shaking caused by a change in acceleration generated in the variable damping device at the time of a wind response due to a small earthquake or a typhoon.
[0013]
In the conventional variable damping device for a vibration control structure described in the above publication, a large acceleration is instantaneously generated when the damping coefficient is switched before reaching the maximum amplitude point in one cycle of the damping operation. In this case, the damping coefficient is finely switched to three or more steps to suppress the shaking and improve the comfort.
[0014]
On the other hand, the hydraulic damper according to the present invention is designed to reduce the unloading time by giving priority to the damping performance when the vibration external force is less than a predetermined value when a small vibration external force is generated. When it is judged that the case does not require the unloading, by adjusting the damping coefficient for the external vibration force, the unloading time is made longer by giving priority to making the unloading time longer than the damping performance. This is different from the conventional example described in the above publication in that the sound is reduced to suppress the noise.
[0015]
The present invention detects the pressure (pressure difference) of the oil chamber and the displacement of the piston (piston rod) to detect whether the vibration is a large earthquake or a mere wind. Based on the detection result, the open / close state of each open / close control valve is determined. Then, by controlling each of the open / close control valves so as to maintain such an open / closed state during one cycle of the damping operation, the unloading time is extended when a small external vibration force is generated. The impact noise is reduced, but this is not described anywhere in the prior art disclosed in the above publication.
[0016]
[Means for Solving the Problems]
A hydraulic damper according to the present invention has the following features.
In a hydraulic damper, a plurality of oil passages communicating between a pair of hydraulic chambers provided on both sides of a piston in a hydraulic cylinder are arranged in parallel, and an open / close control valve is provided in each of the plurality of oil passages.
Each detection means for detecting each pressure of the hydraulic chamber and the displacement of the piston,
Calculating means for calculating the magnitude of the external vibration force based on the pressure and the displacement detected by each of the detecting means;
Control means for adjusting and controlling the length of unloading time by controlling the open / close state of each of the open / close control valves based on the magnitude of the external vibration force calculated by the calculation means. .
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
1 and 2 are views referred to for describing an embodiment of a hydraulic damper according to the present invention.
[0018]
The hydraulic damper 31 shown in FIG. 1 has substantially the same configuration as the open / close control valve V1 of the conventional hydraulic damper 11, and includes two open / close control valves V11 and V12 arranged in each of the parallel oil passages 5. A flow control valve 20 is provided in series with each of the oil passages 5 of the open / close control valves V11 and V12.
[0019]
Normally, the throttle valve V13 at the time of power failure performs the operation of the fail-safe function. However, the same operation as the opening / closing control valves V11 and V12 is performed by the control circuit 27 (corresponding to arithmetic means and control means) as necessary. Is different from the conventional throttle valve V3 when the power is cut off in the hydraulic damper 11 in that it can be controlled to perform the following operation.
[0020]
The relief valve V2 is not controlled by the control circuit 27. When the oil passage 5 or the hydraulic chamber 4A or 4B has a high pressure close to the strength limit that the oil passage 5 or the hydraulic chamber 4A or 4B can withstand, the high pressure causes the hydraulic damper 11 to operate. The oil passage 5 and the hydraulic chambers 4A and 4B are opened to prevent rupture, and operate to release a part of the oil from the high-pressure oil passage 5 and the hydraulic chambers 4A and 4B to other places. This is not different from the relief valve V2 of the conventional hydraulic damper 11 in that it is the same.
[0021]
Since the flow control valve 20 can be adjusted so as to change the amount of oil flowing through the oil passage 5, by changing the initial set flow amount, the flow control valve 20 can adjust the flow amount even in the same oil passage 5 of the same hydraulic damper 31. When the opening / closing control valves V11 and V12 of the oil passage 5 provided with the valve 20 are opened, the unloading time of the same vibration external force by the hydraulic damper 31 can be changed.
[0022]
[Operation of hydraulic damper]
The operation of the hydraulic damper 31 according to the present embodiment will be described below.
[0023]
First, the pressures P ₁ and P _{2 of} the hydraulic chambers 4A and 4B detected by the pressure gauges 8 and 9 (corresponding to detecting means), the hydraulic cylinder 2 and the piston 3 detected by the displacement gauge 10 (corresponding to detecting means). The control circuit 27 calculates the magnitude of the oscillating external force based on the relative displacement △ d with the (piston rod 6).
[0024]
The control circuit 27 controls the open / close state of each of the open / close control valves V11 and V12 in various combinations based on the calculated external vibration force, thereby eliminating the pressure difference between the hydraulic chambers 4A and 4B. To attenuate external vibration forces. The open / close state of each open / close control valve at this time is maintained during one cycle of the damping operation.
[0025]
For example, as shown in FIG. 2, when the vibration force F is small vibration force F _1, such as wind load level, when you open only off control valve V11 is unloading time t _3, only the opening and closing control valve V12 when opened the unloading time _{t 2,} is the unloading time _{t 1} when you open both the opening and closing control valve V11, V12.
[0026]
The vibration force when F is greater vibration force F ₂ as seismic loads level, unloading time t ₆ when opened only off control valve _V11, unloading time when only the open-off control valve V12 t _5, is the unloading time _{t 4} when opening both the opening and closing control valve V11, V12.
[0027]
The open / close state of the open / close control valves V11 and V12 by such control is maintained at the same open / close state as long as the magnitude of the external vibration force F does not change. It is controlled by the control circuit 27 so as to change to the optimal open / close state of the open / close control valves V11 and V12.
[0028]
According to such a hydraulic damper 31, when the vibration force F is small vibration force F _1, such as wind load level, the control circuit 27 by controlling to open only off control valve V11, the longest unloading since damping vibration force F ₁ at time t _3, it is possible to reduce noise due to unloading sound extended unloading time t.
[0029]
Also when the vibration force F is the vibration force F _2, such large as seismic loads level, the control circuit 27 by controlling to open both the opening and closing control valve V11, V12, shortest vibration at unloading time t ₄ the external force F ₂ , the unloading time t can be shortened most and the damping performance of the hydraulic damper 31 can be significantly improved.
[0030]
Further, in the present embodiment, when the vibration force F is larger vibration force F ₂ as seismic loads level, the control circuit 27 to open simultaneously with the opening and closing control valves V11 and V12 the throttle valve V13 operation when deenergized In addition, it is possible to control to turn off the power supply to the throttle valve V13 when the power is cut off.
[0031]
As a result, the moving speed of the oil between the hydraulic chambers 4A and 4B passing through the oil passage 5, the opening / closing control valves V11 and V12, the flow regulating valve 20, and the cut-off operation throttle valve V13 is increased, as shown in FIG. it is possible to shorten than the shortest unloading time t _4, it is possible to further improve the damping performance of the hydraulic damper 31.
[0032]
As described above, the flow control valve 20 provided in the oil passage 5 of the on-off control valves V11 and V12 changes the initial set flow rate to reduce the external vibration force when the on-off control valves V11 and V12 are opened. Since the unloading time can be changed, the length of the unloading time of the same hydraulic damper 31 for the same magnitude of the vibration external force can be more finely adjusted.
[0033]
In the above-described embodiment, a description has been given of a case in which the two on-off control valves V11 and V12 are provided in parallel with the oil passage 5, but three or more on-off control valves are provided in parallel with the oil passage 5. In this case, the number and combination of the open / close control valves to be controlled are variously changed, so that it is possible to perform finer adjustment control of the length of the unloading time.
[0034]
As described above, the embodiments of the present invention have been specifically described. However, the present invention is not limited to the above embodiments, and various other changes may be made based on the technical idea of the present invention. It is possible.
[0035]
【The invention's effect】
As described above, according to the hydraulic damper of the present invention, the open / close state of each of the open / close control valves provided in the plurality of parallel oil passages is controlled, and the unloading time is adjusted according to the magnitude of the generated external vibration force. By adjusting and controlling the length, the unloading time of a large external vibration force such as an earthquake load level can be shortened to improve the damping performance, and the unloading time of a small external vibration force such as a wind load level can be improved. The length of the unloading time of the hydraulic damper can be adjusted in accordance with the magnitude of the external vibration force, for example, the unloading sound can be reduced by extending the length of the unloading sound.
[0036]
In addition, since it is possible to control the throttle valve V13 to be opened and operated together with the other opening / closing control valves V11 and V12 as needed even in a normal state, the length of the unloading time of the hydraulic damper can be increased. Can be further expanded.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a hydraulic damper 31 according to one embodiment of the present invention.
FIG. 2 is a graph illustrating a relationship between an external vibration force F and an unloading time t for explaining the operation of the hydraulic damper 31.
FIG. 3 is a block diagram showing a conventional hydraulic damper 11.
[Explanation of symbols]
2 hydraulic cylinder 3 piston 4A, 4B hydraulic chamber 5 oil passage 6 the piston rod 8,9 pressure gauge 10 displacement meter 11 hydraulic damper 17 control circuit 20 flow rate control valve 27 the control circuit 31 hydraulic damper _P 1, _{P 2} pressure F, _{F 1} , _{F 2} vibrating force _t 1 ~t ₄ unloading time V1, V11, V12-off control valve V2 relief valve V3, V13-energized during operation throttle valve

Claims (5)

In a hydraulic damper, a plurality of oil passages communicating between a pair of hydraulic chambers provided on both sides of a piston in a hydraulic cylinder are arranged in parallel, and an open / close control valve is provided in each of the plurality of oil passages.
Each detection means for detecting each pressure of the hydraulic chamber and the displacement of the piston,
Calculating means for calculating the magnitude of the external vibration force based on the pressure and the displacement detected by each of the detecting means;
A hydraulic damper having control means for adjusting and controlling the length of unloading time by controlling the open / close state of each of the open / close control valves based on the magnitude of the external vibration force calculated by the calculation means. The hydraulic damper according to claim 1, wherein the control unit is a control unit that individually controls opening / closing of an opening / closing control valve provided in each of the plurality of oil passages. The hydraulic damper according to claim 1, wherein a flow control valve is provided in at least one of the plurality of oil passages in series with the on-off control valve. 4. An open / close control valve having a fail-safe function of performing an operation reverse to that of another open / close control valve depending on an energized state, wherein at least one of the open / close control valves provided in each of the plurality of oil passages is an open / close control valve. A hydraulic damper according to any of the claims. The open / close control valve having the fail-safe function has a function of being controlled by the control unit to switch to perform the same operation as another open / close control valve when an external vibration force greater than a set position is applied. 4. The hydraulic damper according to 4.

Images