JPH11182617A - Frequency-sensitive-type hydraulic vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain or insulate vibration of a vibration controlled object according to a frequency region, and prevent partial effective phenomena of vibration control effect by certainly switching a hydraulic circuit. SOLUTION: A constant pressure valve 16 is opened by hydraulics of a contracting first (second) pressure chamber 9 (10) to deliver oil to an oil reservoir 11, and damps vibration in a high frequency region. A resistant orifice 17 provides resistance to oil flow to the oil reservoir and damps vibration in a low frequency region. A valve element of a control valve 19 has a measuring orifice for passing constant-pressure and constant-flow oil from the constant pressure valve 16, and a return orifice for discharging the oil to the first and second pressure chamber 9, 10 sides. A switching valve 18 is closed by the oil sent from the measuring orifice and is switched to insert the resistant orifice 17 between the constant pressure valve 16 and the oil reservoir 11. The oil in a valve chamber of the switching valve 18 is discharged through the return orifice to return the valve element to the initial opening position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is applicable to a column structure having a tendency to become large, such as a high-rise building, a bridge or a plant.
The present invention relates to a hydraulic vibration damping device used for transportation equipment with various vibrations, such as a railway car and an automobile, which operate at a higher speed.

[0002]

2. Description of the Related Art In a large beam-column structure, various vibration external forces act due to wind, earthquake, and the like, but there are few fixed walls to secure a wide space, and it is difficult to attenuate the vibration by the structure itself. Even in high-speed transportation equipment, various external vibration forces act depending on the speed and road surface conditions. In general, the characteristics of the vibration damping device can be represented by a change in the vibration transmissibility with respect to the frequency, and each curve is as shown in FIG. In the figure, the horizontal axis represents the ratio of the frequency to the resonance frequency (ω / ωn),
ω / ωn = 1 represents a resonance point. The vertical axis represents the vibration transmissibility. Each curve shows a representative value of the decay rate D, where D =
Numeral 1 is a curve giving a damping coefficient for aperiodic vibration. From this figure, it can be seen that the characteristics of the vibration damping device are such that the larger the damping effect is to be obtained in the low frequency region (hereinafter referred to as the resonance region) bounded by the frequency of ω / ωn = √2, the larger the damping force is. ω
The vibration transmissibility tends to increase in a high frequency region where / ωn> √2 (hereinafter referred to as a non-resonance region). By the way, conventional vibration damping devices are roughly classified into three types, that is, a passive type, an active type, and a semi-active type.

As a passive type vibration damping device, there is a passive type vibration damping device in which a pressure regulating valve on an oil passage gives resistance to a flow of oil in a hydraulic cylinder by movement of a piston due to vibration to attenuate the vibration (Japanese Patent Laid-Open No. Hei. 321968). The characteristic of this damping device is that the damping coefficient is fixed, so that sufficient damping force can be generated in the resonance region to reduce the vibration transmissibility, but the damping coefficient is large in the non-resonance region. , The vibration transmissibility is larger than those of other types.

[0004] As an active-type vibration damping device, when an external vibration force such as an earthquake acts on an object to be damped, a reactive force using external energy is positively applied to a structure to lower the vibration transmission rate. . Ideally, this vibration damping device is lower than the curve of D = 1 in the resonance region and approaches the curve of D = 0 in the non-resonance region. Therefore, the vibration damping device can obtain the minimum vibration transmissibility regardless of the resonance or non-resonance region, and can particularly reduce the vibration transmissibility to 1 or less in the resonance region.

[0005] As a semi-active type vibration damping device, there is a device in which an attenuation coefficient is changed by electronic control according to input conditions. Although no external energy is used, sufficient damping force is generated in the resonance region to reduce the vibration transmissibility, and in the non-resonance region, the damping force is suppressed to reduce the vibration transmissibility. That is, in this vibration damping device, it is ideal to approach the curve of D = 1 in the resonance region and the curve of D = 0 in the non-resonance region.

[0006]

Among the conventional vibration damping devices, the passive type damping device has a damping coefficient which is too large in the non-resonant region and the vibration transmissibility becomes large. Inevitably, the damping effect in the resonance region becomes insufficient. Active type vibration damping devices require various sensors and a control device such as a computer, and a large drive device based on external energy. In addition, when the response of the control device is delayed, sufficient damping effect cannot be obtained. In addition, it is necessary to take measures in the event of an electrical abnormality, and there is a problem in that it is not practical in terms of vibration suppression effect, reliability, and cost. The semi-active type also does not use external energy,
As with the active type, there are problems in terms of vibration damping effect, reliability, and the like.

As a hydraulic valve that opens and closes according to a specific frequency such as a resonance region or a non-resonance region, FIG.
There is a spool valve as shown in FIG. This valve 20 is provided with the valve body 2
A valve chamber 22 is provided on both sides of the valve body 1, and the valve element 21 is held at a neutral position by a pressure adjusting spring 23. An orifice 24 opens in the valve chamber 22. The spool valve 20 is provided in the valve chamber 2
The valve element 21 is moved by the hydraulic pressure acting on the
Open and close 5,26. At this time, the hydraulic pressure acts on the valve chamber 22 through the orifice 24. Therefore, when the vibration frequency is higher than a specific frequency, the amount of the oil passing through the orifice 24 is small, the amplitude of the valve body 21 is small, and the communication passage 25 , 2
In the case of vibration having a low frequency without closing the valve 6, a large amount of oil passes through the orifice 24, the amplitude of the valve body 21 increases, and the communication passage 25 or 26 can be closed. Accordingly, it is conceivable that the spool valve 20 is applied to a change in the hydraulic pressure of the hydraulic vibration damping device, and the hydraulic circuit is switched according to the vibration frequency to cope with various vibrations.

In such a spool valve 20, on the premise that the center of the vibration corresponds to the neutral position of the valve body, the open state of the spool valve in the vibration in the high frequency region is maintained, and the vibration is isolated. Nature is secured. However, if the vibration in the high frequency region lasts for a long time, the center of the vibration shifts from the neutral position of the valve body, closing one oil passage,
There is a problem that the desired damping effect cannot be obtained, that is, a so-called one-sided state occurs. Therefore, the present invention suppresses the vibration of the vibration damping target by generating a damping force in a low frequency region including a resonance frequency bounded by a specific frequency by a mechanical structure, and in a high frequency region. It is an object of the present invention to provide a compact frequency-sensitive hydraulic vibration damping device that reduces vibration damping force to ensure vibration isolation and more reliably switches hydraulic circuits to prevent half-cut.

[0009]

In order to solve the above-mentioned problems, according to the present invention, a cylinder 5 is connected to one of a supporting member and a supported member to store oil therein, and the other is connected to a cylinder 5. A piston rod 7 inserted so as to be able to move in and out is connected, and a piston 8 that partitions the inside of the cylinder 5 into first and second pressure chambers 9 and 10 is fixed to the piston rod 7.
An oil reservoir 11 for releasing these pressures is communicated with the first and second pressure chambers 9 and 10, and an oil suction valve 14 that opens and closes to supply oil from the oil reservoir 11 to the pressure chambers 9 and 10 is provided. First, the first and second pressure chambers 9 and 10 which are contracted by vibration are opened by hydraulic pressure respectively to discharge oil to the oil reservoir 11 and to insulate vibration in a high frequency region bounded by a predetermined frequency. And a second constant pressure valve 16, a valve chamber 19 a of the control valve 19 communicates with the first and second pressure chambers, respectively, and a metering orifice 19 d for passing a constant flow of oil at a constant pressure by the constant pressure valve 16 to the valve body 19 b. Along with
The first and second pressure chambers 9 and 10 are provided so as to be opened by the negative pressure to discharge the oil, and the valve chamber 18 a of the switching valve 18 is controlled by the control valve 1.
The first and second pressure chambers 9 and 10 are communicated with each other through the pressure chamber 9 and closed by hydraulic pressure from the pressure chamber through the measuring orifice by the vibration in the low frequency range, so that the constant pressure valve 16 and the oil reservoir 1 are closed.
1 while the resistance orifice 17 is inserted between them, while the oil is discharged by the control valve 19 and the valve element 18b returns to its original position.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. 1 is a front view of a frequency-sensitive hydraulic damping device according to the present invention, FIG. 2 is a longitudinal sectional view, FIG. 3 is an explanatory view, FIG. 4 is a sectional view taken along the line IV-IV of FIG. 2, and FIG. 6 is a sectional view taken along line VI-VI of FIG. FIG.
As shown in FIG. 5 to FIG. 5, the frequency-sensitive hydraulic damping device 1 includes a main body 2 and valve units 3 respectively provided at lower front and rear sides thereof. The main body 2 is connected to a support or a support such as a construction (not shown) via a pull 4 and a support or support via a pull 6 so that the cylinder 5 can freely enter and exit the cylinder 5. And an inserted piston rod 7. A piston 8 fixed to one end of the piston rod 7 partitions the inside of the cylinder 5 into first and second pressure chambers 9 and 10.

An annular oil reservoir 11 is integrally provided on the outer periphery of the cylinder 5, and the oil reservoir 11 is built in the main body 2. Oil is stored in the oil reservoir 11. Oil passages 12 communicate with the first and second pressure chambers 9 and 10, respectively. Oil passages 13 communicate with the oil reservoir 11 corresponding to the first and second pressure chambers 9 and 10, respectively.

Oil suction valves 14 are provided at both front and rear ends of the cylinder 5, respectively. The oil suction valve 14 is opened between the oil passage 13 and the cylinder 5 so as to supply oil from the oil reservoir 11 to the negative pressure chambers 9 and 10 whose volumes have been expanded. The oil suction valve 14 is provided with a valve chamber 14 a communicating with the oil passage 13.
Inside, a valve element 14b is provided via a pressure adjusting spring 14c. The valve element 14b is urged by a pressure adjusting spring 14c in a direction to close the valve chamber 14a. The partition plate 15 between the oil suction valve 14 and the pressure chambers 9 and 10 has a plurality of oil holes 15a.

The oil passage 12 is provided with a constant pressure valve 16. The constant pressure valve 16 is opened by a predetermined oil pressure from the pressure chambers 9 and 10 contracted by the movement of the cylinder 5 and discharges oil toward the oil reservoir 11 to keep the oil pressure in the oil passage 12 constant. The constant pressure valve 16 has a valve body 16b provided in a valve chamber 16a via a pressure adjusting spring 16c. The valve element 16b is urged by a pressure adjusting spring 16c in a direction to close the valve chamber 16a.

The oil passage 13 is provided with a resistance orifice 17. The resistance orifice 17 is located between the constant pressure valve 16 and the oil reservoir 11, and when a constant or higher oil pressure acts on the constant pressure valve 16, reduces the flow rate of the oil to give resistance to the flow.

The switching valve 18 closes the gap between the constant pressure valve 16 and the oil passage 13 and inserts the resistance orifice 17 into the oil flow passage from the constant pressure valve 16. The switching valve 18 is provided in the valve chamber 1
A valve element 18a is provided inside 8a via a pressure adjusting spring 18c. The valve element 18a is urged by a pressure adjusting spring 18c in a direction to open the valve chamber 18a.

The control valve 1 is provided between the switching valve 18 and the oil passage 12.
9 are provided. The control valve 19 has a valve body 19b provided in a valve chamber 19a via a pressure adjusting spring 19c. The valve element 19b is urged in a direction to close the valve chamber 19a. A metering orifice 19d is opened at an end of the valve body 19b. When a constant oil pressure is applied to the oil passage 12 by the constant pressure valve 16, the metering orifice 19 d allows a constant flow of oil to pass therethrough to move the valve body 18 b to the valve chamber 18 a of the switching valve 18. A return orifice 19 is provided on the side of the valve body 19b.
e is open. When the pressure chamber becomes negative pressure, the return orifice 19e opens the valve body 19b, so that the oil in the valve chamber 18a of the switching valve 18 is discharged through the return orifice 19e to return the valve body 18b to the original position.

As shown in FIG. 6, in the valve case 3a of the valve unit 3, a constant pressure valve 16 is provided at one end, a control valve 19 is provided at the other end, and a switching valve 18 is provided at a substantially intermediate portion. It is arranged and is detachably incorporated in the valve case 3a.

In this frequency-sensitive hydraulic damping device, when a relative displacement due to vibration occurs between the support and the supported member, the piston rod 7 is pushed into the cylinder 5 or pulled out of it. Now, when the piston 8 moves to the left as shown in FIG. 3 due to the long-period vibration of the resonance region, the negative pressure of the second pressure chamber 10 causes the oil absorption valve 14 to move.
Is opened, and oil is supplied from the oil reservoir 11 to the second pressure chamber 10. At the same time, the contracting first pressure chamber 9
The constant pressure valve 16 on the side opens to keep the oil pressure constant,
A constant flow of oil flows into the switching valve 18 through the metering orifice 19d of the control valve 19, and the switching valve 18 closes. Thus, the oil in the first pressure chamber 9 flows through the resistance orifice 17, where the flow is throttled and vibration is effectively damped.

On the other hand, if the vibration in the non-resonance region has a short cycle, the reciprocating reciprocation of the piston 8 is performed in a short time, and a small amount of oil passes through the measuring orifice 19d.
8, the moving distance of the valve element 18b is short, and the switching valve 18 is not closed. Therefore, the oil flows into the oil reservoir 11 from the constant pressure valve 16 via the switching valve 18, and generates a damping force as small as possible against vibration, thereby isolating the vibration.

When the piston 8 reverses (goes to the right) during vibration, the oil pressure in the communication passage 12 on the first pressure chamber 9 side drops, the constant pressure valve 16 closes, the control valve 19 opens, and the valve chamber 19a
The oil inside is returned and discharged through the orifice 19e.
The valve element 19b returns to the initial open position, and the next operation is prepared, thereby preventing the one-way operation.

Further, since the valve unit 3 is arranged at the lower part of the apparatus and is formed flat, the center of gravity is low, and it is stable.
Rollover can be prevented. In particular, a valve that needs adjustment can be easily attached to and detached from the valve case 3a. Since the valve unit 3 is divided into two corresponding to the respective pressure chambers 9 and 10, the entire size can be reduced.

[0012]

As described above, according to the present invention, a vibration can be effectively suppressed by generating a damping force with respect to a vibration in a low frequency region bounded by a predetermined frequency. Vibration can be insulated by reducing the vibration transmissibility without generating any damping force in the frequency range. Also,
Since it has a mechanical structure that does not involve electrical control, it has no delay in response to vibration, is reliable, is relatively inexpensive, and is generally practical. Further, it is possible to reliably switch the hydraulic circuit, and it is possible to effectively prevent one-sided cutting.

[Brief description of the drawings]

FIG. 1 is a front view of a frequency-sensitive hydraulic damping device according to the present invention.

FIG. 2 is a longitudinal sectional view of a frequency-sensitive hydraulic damping device.

FIG. 3 is an explanatory diagram of a frequency-sensitive hydraulic damping device.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a sectional view taken along line VV of FIG. 2;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 7 is a longitudinal sectional view of a spool valve.

FIG. 8 is a graph showing characteristics of a vibration transmissibility of a typical vibration system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frequency-sensitive hydraulic damping device 2 Main body 3 Valve unit 6 Cylinder 8 Piston rod 9 Pressure chamber 10 Pressure chamber 11 Oil reservoir 14 Oil absorption valve 16 Constant pressure valve 17 Resistance orifice 18 Switching valve 18a Valve chamber 18b Valve body 19 Control valve 19d Measuring orifice 19e Return orifice

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16F 9/18 F16F 9/18 9/50 9/50

Claims (1)

[Claims] Claims: 1. A method according to claim 1, wherein the first member is connected to one of a support member and a support member.
A cylinder containing oil therein; a piston rod connected to the other side and inserted into and out of the cylinder so as to be fixed to the piston rod;
And a piston partitioned into a second pressure chamber, an oil reservoir communicating with the first and second pressure chambers to release these pressures, and opening and closing to supply oil from the oil reservoir to the pressure chamber. An oil suction valve and a high frequency region bounded by a predetermined frequency by discharging oil to an oil reservoir while maintaining a predetermined pressure by opening each with the hydraulic pressure of the first or second pressure chamber contracted by vibration; A constant-pressure valve that insulates the vibrations of the first and second pressure chambers, and discharges oil to an oil reservoir by hydraulic pressure in the first or second pressure chamber due to vibration in a low-frequency region bounded by a predetermined frequency. A resistance orifice that attenuates vibration in a low frequency region; and a measurement orifice that communicates with the first and second pressure chambers and passes a constant flow of oil at a constant pressure by the constant pressure valve to a valve body, Negative pressure in first and second pressure chambers A control valve that opens more and discharges oil; and a fixed amount of oil that is communicated from the pressure chamber through the metering orifice due to vibration in a low frequency range, communicating with the first and second pressure chambers via the control valve. And a switching valve that inserts the resistance orifice between the constant pressure valve and the oil reservoir while the oil is discharged by the control valve and the valve element returns to the original position. By switching the oil flow passage at a frequency, vibration in a high frequency region is insulated by the constant pressure valve, while vibration in a low frequency region is attenuated by the resistance orifice. Damping device.