JP7492690B2 - Oil Damper System - Google Patents

Description

The present invention relates to an oil damper system that can improve the damping performance of an oil damper that is designed to change the damping performance.

Oil dampers are known that are installed between the ground and a building to absorb earthquake energy and attenuate earthquake motion acting on the vibration input side and the vibration attenuation target side, for example, a building supported on the ground by seismic isolation bearings.

Patent Document 1 is known as an example of this type of oil damper. The "oil damper for seismic isolation device" of Patent Document 1 is an oil damper for seismic isolation device that, when used in combination with a seismic isolation bearing, constitutes a seismic isolation device and absorbs and attenuates the energy of earthquake shaking in order to suppress relative displacement between the foundation and the upper building during an earthquake. The oil damper includes a first cylinder connected to one of the foundation and the upper building, a first piston slidably provided within the first cylinder and dividing the first cylinder into two oil chambers, left and right, a first hydraulic cylinder having a pressing portion, a piston rod provided integrally with the first piston and connected to the other of the foundation and the upper building, a communication passage that communicates the two oil chambers with each other outside the first hydraulic cylinder, a valve body provided midway through the communication passage and that opens and closes the communication passage, a movable spring seat, and a spring seat that is provided between the valve body and the spring seat and biases the valve body toward the closing side. The damping valve has a spring, and as the first piston of the first hydraulic cylinder is displaced, the valve body opens due to hydraulic pressure supplied from the oil chamber of the first cylinder, generating a damping force; a second cylinder that communicates with the back side of the spring seat of the damping valve, a second piston that is slidably provided in the second cylinder, and a second piston rod that has an engagement part and is integral with the second piston, and when the displacement of the first piston reaches a predetermined value, the engagement part is pressed by the pressing part of the first piston rod, and the second hydraulic cylinder is configured to compress the spring through the spring seat by introducing hydraulic pressure from within the second cylinder to the back side of the spring seat, thereby increasing the spring force of the spring, thereby increasing the damping force.

Patent No. 4442770

The oil damper disclosed in the background art is an excellent device that, when the displacement of the first piston reaches a predetermined value, introduces hydraulic pressure from within the second cylinder of the second hydraulic cylinder to the back side of the spring seat of the damping valve, increasing the spring force of the spring that biases the valve body to open and close the communication passage that communicates with the first hydraulic cylinder, thereby strengthening the damping force, and can change the damping performance according to the stroke of the first piston rod caused by seismic motion.

It would be desirable to further improve the device in various ways, and there was a need to devise proposals for such improvements.

The present invention was devised in consideration of the above-mentioned problems with the conventional technology, and aims to provide an oil damper system that can improve the damping performance of oil dampers that are designed to change the damping performance.

The oil damper system according to the present invention comprises a uniflow-type oil damper having an outer cylinder connected to one of the vibration input side and the vibration damping target side, a piston rod connected to the other of the vibration input side and the vibration damping target side, and a pressure regulating valve unit that regulates and absorbs energy by opening a valve body biased by a pressure regulating spring with the fluid pressure to regulate the outflow pressure of the hydraulic oil flowing out of the inner cylinder due to the movement of the piston, a transmission member that transmits the extension stroke amount of the piston rod that moves the piston, and a transmission member that is provided along the extension stroke direction of the piston rod and is filled with control oil. and a pair of control cylinder units each having a cylinder case filled with oil and a control piston that discharges control oil in the cylinder case from a discharge port by extension of the control piston rod, and when an excessive extension stroke or excessive contraction stroke exceeding a predetermined extension stroke amount occurs in the piston rod, the control piston rod is extended by the excessive extension stroke amount or excessive contraction stroke amount by the transmission member, thereby discharging control oil from the discharge port, and a communication portion that communicates the discharge ports of the pair of control cylinder units, and a communication portion that communicates with the communication portion and and a control oil circulation system connecting an introduction port of the pressure regulating valve unit to the introduction port of the pressure regulating valve unit, the pressure regulating valve unit including a valve body having the introduction port, the pressure regulating spring provided in the valve body, the valve element provided in the valve body and opened by an outflow pressure of hydraulic oil resisting the spring force of the pressure regulating spring, and a spring seat provided in the valve body and moved so as to compress the pressure regulating spring by the hydraulic pressure of control oil introduced from the introduction port, the control oil circulation system being disposed between the communication portion and the introduction port of the pressure regulating valve unit, and the hydraulic pressure of control oil acting from the spring seat When the hydraulic pressure of the control oil from one of the control cylinder units exceeds the valve opening pressure, the control oil is introduced into the inlet port, and when the hydraulic pressure is equal to or lower than the valve opening pressure, the control oil is allowed to flow into the discharge port of the other of the control cylinder units through the communication part. The spring force of the pressure adjustment spring is changed according to the amount of excess extension stroke or the amount of excess contraction stroke. A pair of hanging devices are provided at both ends of the outer cylinder in the longitudinal direction, and a base for mounting the pair of control cylinder units is connected between the hanging devices.

The base is attached to the sling with a breakable connector to protect the transmission member.

The base is provided with a fixing member that holds the pair of control cylinder units and is bolted to the base, and is also provided with a number of bolt holes for bolting the fixing member to allow the fixing member's joining position to be changed.

The oil damper system of the present invention is targeted at oil dampers that have variable damping performance, and it is possible to improve the installation structure of the control cylinder unit and facilitate installation and removal work.

1 is an explanatory diagram illustrating a hydraulic circuit of a preferred embodiment of an oil damper system according to the present invention. FIG. FIG. 2 is a plan view showing the device configuration of the oil damper system of FIG. 1 in an installed state. FIG. 2 is a side view showing the device configuration of the oil damper system of FIG. 1 in an installed state. 2 is a cross-sectional view illustrating a pressure regulating valve unit provided in the oil damper system of FIG. 1. FIG. 2 is a cross-sectional view illustrating a control cylinder unit provided in the oil damper system of FIG. 1. 2 is an explanatory diagram illustrating a mounting portion of an oil damper provided in the oil damper system of FIG. 1 and a mounting state of a base end of a transmission member to a piston rod. FIG. 7 is an explanatory diagram illustrating another example of the mounting state of the base end of the transmission member shown in FIG. 6 to the piston rod. FIG. This is a view taken along line AA in FIG. This is a view taken along line BB in FIG. 2, illustrating a protective pipe provided in the oil damper system of FIG. 1. FIG. 11 is a partially cutaway side view illustrating the protective tube shown in FIG. 10. 2 is an explanatory diagram illustrating a joint portion of a base provided in the oil damper system of FIG. 1 to a hanging tool. FIG. 13 is an explanatory diagram illustrating a state in which a fixing member is joined to the base illustrated in FIG. 12 . FIG. 14 is an explanatory diagram illustrating a state in which a large number of bolt holes for bolting the fixing member shown in FIG. 13 are formed in the base. FIG.

Below, a preferred embodiment of the oil damper system of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is an explanatory diagram illustrating the hydraulic circuit of the oil damper system according to this embodiment. Figure 2 is a diagram showing a plan view of the device configuration of the oil damper system of Figure 1 in an installed state. Figure 3 is a diagram showing a side view of the device configuration of the oil damper system of Figure 1 in an installed state. Figure 2 may be a side view of the installed state, and Figure 3 may be a plan view of the installed state.

The oil damper system 1 according to this embodiment is installed between the vibration input side and the vibration damping target side, for example, between the foundation of the ground 2 or the building 3 that moves together with the ground 2 to absorb earthquake energy, and the building 3 supported on the foundation by seismic isolation bearings. However, it goes without saying that the oil damper system 1 according to this embodiment may be installed in any vibration transmission system for the purpose of vibration damping.

The oil damper system 1 in this embodiment is mainly composed of a uniflow type oil damper 4.

The uniflow type oil damper 4 itself is known, and comprises an outer cylinder 5, a hydraulic oil reservoir 6 provided inside the outer cylinder 5 in which hydraulic oil F is stored while maintaining a free surface, an inner cylinder 7 provided inside the outer cylinder 5, a piston 8 provided inside the inner cylinder 7 so as to slide freely in a liquid-tight state and divides the inside of the inner cylinder 7 into two hydraulic chambers, a first hydraulic chamber R1 and a second hydraulic chamber R2, and a piston 8 integrally connected to the piston 8, which penetrates the inner cylinder 7 and protrudes outside the outer cylinder 5 in a liquid-tight state. It is composed of a piston rod 9 that is slidably operated, a pressure regulating valve unit 10 that is provided between the first hydraulic chamber R1 and the hydraulic oil reservoir 6 and generates an energy absorbing action, a first damper check valve 11 that is provided between the hydraulic oil reservoir 6 and the second hydraulic chamber R2 and allows hydraulic oil F to flow only from the hydraulic oil reservoir 6 to the second hydraulic chamber R2 and blocks backflow, and a second damper check valve 12 that is provided on the piston 8 and allows hydraulic oil F to flow only from the second hydraulic chamber R2 to the first hydraulic chamber R1 and blocks backflow.

The pressure-receiving area of the piston 8 is set to half the area on the first hydraulic chamber R1 side to which the piston rod 9 is connected compared to the area on the second hydraulic chamber R2 side.

As shown in FIG. 4, the pressure regulating valve unit 10 is composed of a valve body 13 having a hydraulic oil inlet port P1 that communicates with the first hydraulic chamber R1 of the inner cylinder 7 and a hydraulic oil outlet port P2 that communicates with the hydraulic oil reservoir 6, a valve element 14 that is movably provided within the valve body 13 and opens and closes the hydraulic oil inlet port P1 when moved, a spring seat 15 that is disposed within the valve body 13 on the opposite side to the valve element 14 and is movably provided in a liquid-tight state relative to the valve body 13, and a pressure regulating spring 16 that is sandwiched within the valve body 13 between the spring seat 15 and the valve element 14 and is supported by the spring seat 15 to bias the valve element 14.

That is, the valve body 14 is disposed at one end of the pressure adjustment spring 16, and the spring seat 15 is disposed at the other end of the pressure adjustment spring 16.

In the pressure regulating valve unit 10, the pressure regulating spring 16 biases the valve body 14 toward the hydraulic oil inlet port P1, and the biasing force of the pressure regulating spring 16 causes the valve body 14 to close the hydraulic oil inlet port P1, thereby isolating the first hydraulic chamber R1 from the hydraulic oil reservoir 6. On the other hand, the valve body 14 opens the hydraulic oil inlet port P1 against the biasing force of the pressure regulating spring 16, thereby connecting the hydraulic oil inlet port P1 to the hydraulic oil outlet port P2, thereby connecting the first hydraulic chamber R1 to the hydraulic oil reservoir 6.

The valve body 13 of the pressure regulating valve unit 10 is further provided with an inlet port P3 (described later) facing the rear surface of the spring seat 15 (the side opposite to the side where the pressure regulating spring 16 is installed).

The operation of the uniflow type oil damper 4 is such that when the piston rod 9 is pulled out of the outer cylinder 5 in the extension direction and the piston 8 moves to narrow the first hydraulic chamber R1 of the inner cylinder 7, the hydraulic oil F flows out of the first hydraulic chamber R1 toward the pressure regulating valve unit 10.

The outflow pressure of the hydraulic oil F flowing out of the first hydraulic chamber R1 acts on the hydraulic oil inlet port P1, moving the valve body 14, which is biased by the pressure regulating spring 16, against the spring force of the pressure regulating spring 16, thereby opening the hydraulic oil inlet port P1.

When the hydraulic oil inlet port P1 is opened, the hydraulic oil F flows through the gap between the inner surface of the valve body 13 and the valve element 14 inside the valve body 13 of the pressure regulating valve unit 10 toward the hydraulic oil outlet port P2, and then flows from the hydraulic oil outlet port P2 toward the hydraulic oil reservoir 6.

The opening action of the valve body 14 caused by the outflow pressure of the hydraulic oil F from the first hydraulic chamber R1 is restricted by the pressure regulating spring 16, thereby exerting the energy absorption effect of the oil damper 4.

When the first hydraulic chamber R1 is narrowed and hydraulic oil F flows out of the first hydraulic chamber R1, hydraulic oil F flows into the second hydraulic chamber R2, which is widened, from the hydraulic oil reservoir 6 through the first damper check valve 11.

On the other hand, when the piston rod 9 is retracted toward the outer cylinder 5 in the contraction direction and the piston 8 moves to expand the first hydraulic chamber R1 of the inner cylinder 7, narrowing the second hydraulic chamber R2 accordingly. Therefore, because the first damper check valve 11 is closed, and because the pressure-receiving area of the piston 8 on the second hydraulic chamber R2 side is twice that of the first hydraulic chamber R1 side as described above, the hydraulic oil F in the second hydraulic chamber R2 with increased pressure is sent to the first hydraulic chamber R1 through the second damper check valve 12 of the piston 8 in an amount twice that when the piston rod 9 is extended, and half of that amount of hydraulic oil F is further pushed out of the first hydraulic chamber R1 and flows out toward the pressure regulating valve unit 10. In the first hydraulic chamber R1, half of the amount of hydraulic oil F is replenished by the inflow of twice the amount of hydraulic oil F from the second hydraulic chamber R2, so that the first hydraulic chamber R1 is always full.

When the piston rod 9 is contracted, as in the case of extension, the outflow pressure of the hydraulic oil F flowing out of the first hydraulic chamber R1 acts on the hydraulic oil inlet port P1, moving the valve body 14 biased by the pressure regulating spring 16 against the spring force of the pressure regulating spring 16, thereby opening the hydraulic oil inlet port P1.

When the hydraulic oil inlet port P1 is opened, the hydraulic oil F flows through the valve body 13 of the pressure regulating valve unit 10 toward the hydraulic oil outlet port P2, and then flows from the hydraulic oil outlet port P2 toward the hydraulic oil reservoir 6.

Even when the piston rod 9 contracts, the opening movement of the valve body 14 due to the outflow pressure of the hydraulic oil F from the first hydraulic chamber R1 is restricted by the pressure regulating spring 16, thereby allowing the oil damper 4 to absorb energy.

When the piston rod 9 is extended or retracted, if the sliding distance of the piston 8 is the same, the amount of hydraulic oil F flowing into the pressure regulating valve unit 10 is the same, and therefore the amount of energy absorption is the same.

In this way, in a uniflow type oil damper 4, the hydraulic oil F flows in one direction, flowing out only from the first hydraulic chamber R1 and flowing into only the second hydraulic chamber R2.

Between the first hydraulic chamber R1 and the hydraulic oil reservoir 6, a relief valve 17 is provided to control the release of the hydraulic pressure of the hydraulic oil F in the first hydraulic chamber R1 when the piston rod 9 is operating at high speed.

The oil damper 4 has an outer cylinder 5 connected to one of the vibration input side and the vibration damping target side, for example, the ground 2. The oil damper 4 also has a piston rod 9 connected to the other of the vibration input side and the vibration damping target side, for example, the building 3.

When an earthquake causes relative displacement between the ground 2 and the building 3, the piston rod 9 of the oil damper 4 expands and contracts with a stroke amount that corresponds to the amount of relative displacement.

In this specification, the "extension stroke of the piston rod 9" refers to the change in length of the oil damper 4 as the piston rod 9 is pulled outward from the outer cylinder 5 and the inner cylinder 7 and pushed inward, accompanying the reciprocating movement of the piston 8, causing the length dimension of the oil damper 4 to become longer or shorter in the length direction of the piston rod 9. Similarly, the "extension stroke of the piston rod 9" refers to the change in length of the oil damper 4 as the length dimension of the oil damper 4 becomes longer in the length direction of the piston rod 9, and the "contraction stroke of the piston rod 9" refers to the change in length of the oil damper 4 as the length dimension of the oil damper 4 becomes shorter in the length direction of the piston rod 9.

The "extension" of the piston rod 9 means that, as the piston 8 reciprocates, the piston rod 9 is pulled out in a direction that protrudes outward from the outer cylinder 5 and the inner cylinder 7, and the length of the oil damper 4 increases in the length direction of the piston rod 9. The "contraction" of the piston rod 9 means that the piston rod 9 is pushed inward into the outer cylinder 5 and the inner cylinder 7, and the length of the oil damper 4 decreases in the length direction of the piston rod 9.

As shown in Figures 1 to 3, the oil damper 4 is provided with a transmission member 18 that transmits the extension stroke amount of the piston rod 9 that moves the piston 8.

The transmission member 18 is formed of a shaft that is long in the extension stroke direction of the piston rod 9. The transmission member 18 has a base end 18a, which is one end in the length direction, attached to the piston rod 9 by an attachment structure described below, and a tip end 18b, which is the other end in the length direction, supported movably outside the outer cylinder 5 by a support structure described below.

The transmission member 18, whose base end 18a is attached to the piston rod 9, slides outside the oil damper 4 in accordance with the extension and contraction of the piston rod 9. When the piston rod 9 performs an extension stroke, the tip 18b moves the same amount in the direction of the extension stroke, and when the piston rod 9 performs a contraction stroke, the tip 18b moves the same amount in the direction of the contraction stroke.

A pair of control cylinder units 19, 19 are provided on the outside of the outer cylinder 5 of the oil damper 4, on either side of the transmission member 18, along the extension stroke direction of the piston rod 9.

One control cylinder unit 19 is configured to operate for the extension stroke of the piston rod 9, and the other control cylinder unit 19 is configured to operate for the contraction stroke.

As shown in FIG. 5, both of these control cylinder units 19, 19 are composed of a cylinder case 20 filled with control oil f, a control piston 21 slidably arranged in the cylinder case 20 in a liquid-tight state, a control piston rod 22 connected at one end to the piston 21 and slidably protruding at the other end outward from the cylinder case 20 in a liquid-tight state, which causes the control cylinder unit 19 to extend and contract, a spring 23 arranged in the cylinder case 20 to bias the control piston 21 in the direction in which the control piston rod 22 contracts, and a discharge port P4 arranged in the cylinder case 20 to discharge the control oil f from inside the cylinder case 20, which is pressurized by the control piston 21 sliding due to the extension operation of the control piston rod 22 against the spring 23.

In this specification, "the control piston rod 22 extends or contracts" refers to the change in length of the control piston rod 22 being pulled out in a direction that protrudes outward from the cylinder case 20 or pushed in in a direction that retracts inward, accompanied by the reciprocating movement of the control piston 21, causing the length dimension of the control cylinder unit 19 to become longer or shorter in the length direction of the control piston rod 22.

The spring 23 is set to a weak spring force that slowly contracts the control piston rod 22.

An operating part 24 is provided at the tip 18b of the transmission member 18, and a passive part 25 is provided at the protruding tip of the control piston rod 22 of the pair of control cylinder units 19 on both sides of the transmission member 18, with which the operating part 24 can be freely engaged and disengaged.

As shown in Figures 1 and 2, the pair of control cylinder units 19, 19 are installed so that the extension directions of their control piston rods 22, 22 are opposite to each other, and the operating part 24 of the transmission member 18 is located between their passive parts 25, 25 in the extension stroke direction of the piston rod 9.

Furthermore, when the piston rod 9 of the oil damper 4 is in a neutral position in the extension stroke direction and the control piston rods 22 are contracted by the springs 23 (in other words, when the oil damper 4 is in a non-operating state), the passive parts 25 of the control cylinder units 19 are spaced apart from the operating part 24 by a distance equal to the predetermined extension stroke amount set for the piston rod 9.

The predetermined extension stroke amount refers to the extension stroke amount S and the retraction stroke amount S that are set equal in the extension stroke direction and the retraction stroke direction, respectively, based on the neutral position N of the piston rod, as shown in Figure 1.

In other words, the actuating part 24 and each of the passive parts 25, 25 are equally spaced apart by a distance equal to the predetermined stroke amount S of the piston rod 9.

When the piston rod 9 is extended or retracted within a predetermined stroke amount S, the operating part 24 of the transmission member 18 moves accordingly, but the operating part 24 does not engage with the passive part 25 of any of the control cylinder units 19, and the control cylinder units 19 are not operated.

When the piston rod 9 experiences an excessive extension stroke that exceeds the predetermined extension stroke amount S, for example, the actuating part 24 engages with the passive part 25 of the control piston rod 22 of one of the control cylinder units 19.

The passive part 25 then extends the control piston rod 22 with an excess extension stroke amount that exceeds the predetermined extension stroke amount S.

The control piston rod 22 is extended, causing the control piston 21 to slide against the spring 23, and control oil f is discharged from the discharge port P4 of the cylinder case 20 for the excess extension stroke.

When the piston rod 9, which repeats the extension and contraction stroke, transitions to a contraction stroke, the operating part 24 of the transmission member 18 disengages from the passive part 25 that engaged with it to extend the control piston rod 22.

If the excess extension stroke amount during the next extension stroke is equivalent to the previous excess extension stroke amount, the control piston rod 22 that was extended during that time is pushed very slowly in the contraction direction by the spring 23 with a weak spring force, and remains in approximately the same position, so no control oil f is discharged. On the other hand, if the excess extension stroke amount increases beyond the previous excess extension stroke, the operating part 24 engages with the passive part 25 again, and the control piston rod 22 is extended again with the increased excess extension stroke amount, and the control oil f is discharged from the control cylinder unit 19 by the amount of the increased excess extension stroke.

When an excess contraction stroke that exceeds the specified extension stroke occurs in the piston rod 9, the control piston rod 22 of the other control cylinder unit 19 is extended in the same manner as described above by the operating part 24 of the transmission member 18, and the excess contraction stroke and the increased amount of control oil f are discharged from the discharge port P4 of the cylinder case 20.

In this way, when the extension stroke amount of the piston rod 9 of the oil damper 4 exceeds the predetermined extension stroke amount S, the control cylinder unit 19 first discharges control oil f for the excess extension stroke amount when it exceeds the predetermined extension stroke amount S, and then repeats the process of discharging control oil f for the excess extension stroke amount that has increased beyond the previous excess extension stroke.

In other words, after the pair of control cylinder units 19, 19 exceeds the predetermined extension stroke amount S, each time the excess extension stroke amount increases, an increased amount of control oil f is discharged.

The extended control piston rod 22 is slowly urged by the spring 23 in the contraction direction back to its original position when, for example, an earthquake subsides and the oil damper 4 ceases operation and becomes inoperative (the piston rod 9 returns to the neutral position N in the extension stroke direction). On the other hand, because the spring force is weakened, the extended position of the control piston rod 22 extended by the operating part 24 and pulled out from the cylinder case 20 is maintained while the oil damper 4 is in operation, and the discharged control oil f does not flow toward the discharge port P4 due to the action of the spring 23.

As shown in Figures 1 to 3, a control oil flow system 26 is provided between the pair of control cylinder units 19, 19 and the pressure regulating valve unit 10.

The control oil flow system 26 is composed of a piping system and has a communication part 27 that connects the discharge ports P4, P4 of a pair of control cylinder units 19, 19, and also connects the communication part 27 to the inlet port P3 of the pressure regulating valve unit 10.

The control oil flow system 26 is provided with a check valve 28 disposed between the communication part 27 and the inlet port P3 of the pressure regulating valve unit 10.

The check valve 28 allows the control oil f to flow from the communication portion 27 toward the inlet port P3 and prevents backflow.

Then, hydraulic pressure is generated on the back surface of the spring seat 15 by the control oil f flowing into the valve body 13 from the inlet port P3, and this hydraulic pressure acts on the check valve 28 as back pressure.

In other words, in the control oil distribution system 26 equipped with the check valve 28, the control oil f discharged from each discharge port P4, P4 flows back and forth between the pair of discharge ports P4, P4, or passes through the check valve 28 and the inlet port P3 to the back surface of the spring seat 15 in the pressure regulating valve unit 10, generating hydraulic pressure on the back surface of the spring seat 15 that changes the spring force of the pressure regulating spring 16.

The piston rod 9 of the oil damper 4 repeatedly extends and contracts alternately, and as a result, the control piston rods 22, 22 of the pair of control cylinder units 19, 19 are also usually extended alternately, and control oil f is discharged alternately and intermittently from each discharge port P4, P4.

The check valve 28 introduces the control oil f into the inlet port P3 when the oil pressure of the control oil f discharged from the outlet port P4 of one of the control cylinder units 19 during the extension operation and acting through the communication part 27 exceeds the valve opening pressure, and on the other hand, when the oil pressure of the control oil f is equal to or lower than the valve opening pressure, it prevents the control oil f from flowing into the inlet port P3.

The control oil f, the flow of which is prevented by the check valve 28, flows through the communication part 27 into the discharge port P4 of the other control cylinder unit 19 that is not being extended.

When an excess extension stroke amount and an excess contraction stroke amount occur, and the stroke amounts increase sequentially, the hydraulic pressure of the control oil f generated by the pair of control cylinder units 19, 19 that are alternately extended acts on the check valve 28, and the check valve 28 allows the control oil f to flow into the inlet port P3 of the pressure regulating valve unit 10 each time the check valve 28 exceeds the valve opening pressure.

As a result, in the valve body 13 of the pressure regulating valve unit 10, the pressure regulating spring 16 is gradually compressed between the valve body 14 by the gradually increasing amount of control oil f that is introduced from the inlet port P3 to the back surface of the spring seat 15, and this contraction causes the spring force of the pressure regulating spring 16 that biases the valve body 14 to increase.

In other words, the spring seat 15 is moved so as to compress the pressure regulating spring 16 by the hydraulic pressure of the control oil f introduced from the inlet port P3, which causes the spring force of the pressure regulating spring 16 to change according to the amount of excess extension stroke or excess contraction stroke.

As shown in FIG. 1, the control oil distribution system 26 is provided with a bypass passage 29 that bypasses the check valve 28 in order to return the control oil f to the pair of control cylinder units 19, 19. In this bypass passage 29, a return valve (e.g., a needle valve) 30 that has a throttling function that can be opened and closed freely and has an adjustable opening degree is provided in parallel with the check valve 28.

This return valve 30 is designed to sequentially return the control oil f sent to the pressure regulating valve unit 10 from the inlet port P3 through the communication part 27 to the discharge ports P4, P4 of the pair of control cylinder units 19, 19, for example, when an earthquake subsides and the oil damper 4 stops operating and becomes inoperative (the piston rod 9 returns to the neutral position N in the extension stroke direction).

On the other hand, the return valve 30 limits the outflow of control oil f from the back surface of the spring seat 15 while the oil damper 4 is in operation.

In FIG. 1, 31 is a hydraulic gauge that displays the hydraulic pressure in the control oil flow system 26, and 32 is an on-off valve for draining the control oil f.

The operation of the oil damper system 1 according to this embodiment will be described. The oil damper 4 is set between the ground 2 and the building 3 with the piston rod 9 in the neutral position N in the extension stroke direction.

For example, when an earthquake occurs and the oil damper 4 starts to operate, if there is no excessive extension stroke or excessive contraction stroke in the extension stroke of the piston rod 9, the pair of control cylinder units 19, 19 will not be operated, and the oil damper 4 will absorb earthquake energy by opening and closing the valve body 14 of the pressure regulating valve unit 10 in response to the outflow pressure of the hydraulic oil F with the initial spring characteristics set in the pressure regulating spring 16.

When an excessive extension stroke amount that exceeds the predetermined extension stroke amount S occurs in the piston rod 9, the control cylinder units 19, 19 are actuated by the actuating portion 24 of the transmission member 18.

When the control piston rod 22 of one of the control cylinder units 19 is extended by either the first over-extension stroke or the over-contraction stroke, and the control oil f is introduced from the discharge port P4 through the check valve 28 to the back surface of the spring seat 15 of the pressure regulating valve unit 10, the pressure regulating spring 16 is compressed, and the pressure regulating valve unit 10 opens and closes the valve body 14 against the outflow pressure of the hydraulic oil F due to the spring characteristics of the pressure regulating spring 16, which have been changed to a spring force greater than the initial spring characteristics, thereby increasing the absorption of earthquake energy.

When the amount of excess extension stroke is within the initial amount of excess extension stroke and does not exceed it, even if the pair of control piston rods 19, 19 are extended by the transmission member 18, the check valve 28 remains closed, and the control oil f discharged from the pair of control cylinder units 19, 19 flows between the discharge ports P4, P4 of the control cylinder units 19, 19 through the communication part 27 of the control oil circulation system 26.

On the other hand, whenever an excess extension stroke amount or excess contraction stroke amount occurs that exceeds the previous excess extension stroke amount, the check valve 28 is opened by the hydraulic pressure of the control oil f discharged from each of the pair of control cylinder units 19, 19, and each time this occurs, the control oil f is introduced into the pressure regulating valve unit 10, causing the spring force of the pressure regulating spring 16 to change by an increasingly large amount.

Therefore, the greater the extension stroke of the piston rod 19 caused by an earthquake, the greater the spring force of the pressure regulating spring 16 of the pressure regulating valve unit 10 can be made, resulting in a greater change in the energy absorption performance.

The oil damper system 1 of this embodiment can control the spring force of the pressure regulating spring 16 of the pressure regulating valve unit 10 with a single check valve 28, and is simpler and ensures higher operational reliability than the hydraulic circuit configuration of the background art, which requires a large number of valves.

When the excess extension stroke amount and excess contraction stroke amount are the same, control oil f is not introduced into the pressure regulating valve unit 10 to prevent the spring force from increasing. This means that, unlike the background art where the spring force increases even when the amounts are the same and a circuit is required to control it, the spring force of the pressure regulating spring 16 does not become too strong, and the spring force of the pressure regulating spring 16 can be accurately and smoothly controlled.

The control oil flow system 26 is provided with a bypass passage 29 that bypasses the check valve 28, and the bypass passage 29 is provided with a return valve 30 in parallel with the check valve 28 to sequentially return the control oil f from the inlet port P4 of the pressure regulating valve unit 10 to the outlet ports P4, P4 of the pair of control cylinder units 19, 19 via the communication part 27. This allows the oil damper 4 and the pair of control cylinder units 19, 19 to smoothly return to the neutral state they were in before operation, for example, after the earthquake has subsided.

Each control cylinder unit 19 includes a cylinder case 20 filled with control oil f, a control piston 21 that discharges the control oil f in the cylinder case 20 from the discharge port P4 when the control piston rod 22 is extended, and a spring 23 that is provided in the cylinder case 20 and biases the control piston rod 22 in the contracting direction. The spring 23 is set to a weak spring force that slowly contracts the control piston rod 22, so that when the oil damper 4 finishes operating (by adjusting the opening/closing or opening degree of the return valve 30 as necessary), the control piston rod 19 can be returned to its original position, and on the other hand, while the oil damper 4 is operating, the control piston rod 22 can be maintained in the extended position, allowing an immediate response to the occurrence of an excess extension/contraction stroke.

<<Improvement of the layout of the control cylinder units 19, 19>>
As shown in Figures 2 and 3, as described above, a pair of control cylinder units 19, 19 are arranged outside the outer cylinder 5, sandwiching the axial transmission member 18 whose operating part 24 reaches the outside of the outer cylinder 5, and are installed so that the extension directions of their control piston rods 22, 22 are opposite to each other and the operating part 24 of the transmission member 18 is located between their passive parts 25, 25 in the extension stroke direction of the piston rod 9.

The pair of control cylinder units 19, 19 are further arranged parallel to each other along the extension stroke direction of the piston rod 9, with their cylinder cases 20, 20 facing each other across the transmission member 18 in a direction intersecting the extension stroke direction of the piston rod 9 (the length direction of the outer cylinder 5 of the oil damper 4), for example, in the width direction (radial direction) of the outer cylinder 5.

More specifically, the pair of control cylinder units 19, 19 are arranged such that their cylinder cases 20, 20 overlap each other in their length direction (the extension stroke direction of the control piston rods 22, 22) in the extension stroke direction of the piston rod 9.

In the oil damper system 1 of this embodiment, the pair of control cylinder units 19, 19 are arranged in parallel rather than in series, so that it can be installed in a space-saving manner compared to a uniflow type oil damper 4, which has a shorter length dimension than a double-rod type oil damper.

The transmission member 18 that operates the pair of control cylinder units 19, 19 is a shaft, and the pair of control cylinder units 19, 19 are arranged to sandwich the transmission member 18, so the space required to install the pair of control cylinder units 19, 19 can also be reduced in the width direction (circumferential direction) of the outer cylinder 5.

The control piston rods 22, 22, which have passive parts 25 at their protruding ends, extend in opposite directions, and a pair of control cylinder units 19, 19 are arranged in parallel, overlapping in the length direction of the cylinder cases 20, 20. The operating part 24 of the transmission member 18 is arranged between the passive parts 25, 25 of the pair of control piston rods 19, 19 along the extension stroke direction of the piston rod 9. This makes it possible to reduce the space required for the extension stroke of the control piston rods 22, 22, which operate in the extension stroke direction of the piston rod 9, by the amount of overlap of the pair of cylinder cases 20, 20, and also reduces the length required to install the pair of control cylinder units 19, 19 in the outer cylinder 5.

<Improvement of the mounting structure of the transmission member 18 to the piston rod 9>
6, the attachment state of the base end 18a of the transmission member 18 to the piston rod 9 will be described. An end fitting 38, which will be described later, is screwed to the tip 9a of the piston rod 9 in the extension stroke direction.

The end metal fitting 38 is provided with a mounting seat 35 having a threaded portion that is screwed through the end metal fitting 38 and pressed against the piston rod 9 to prevent loosening of the threaded connection between the end metal fitting 38 and the piston rod 9. A spherical plain bearing 36 is supported on the mounting seat 35, and the base end 18a of the transmission member 18 is releasably connected to the spherical plain bearing 36.

Therefore, the base end 18a of the transmission member 18 is attached to the piston rod 9 via the spherical plain bearing 36.

The spherical plain bearing 36 is a well-known device consisting of a sphere surrounded by a spherical seat, and it transmits force to the transmission member 18 only in the direction of the extension and retraction stroke of the piston rod 9, cushioning and absorbing the various movements of the piston rod 9 relative to the transmission member 18 so that no load is applied from any other direction.

Furthermore, when an excessive load is applied between the base end 18a of the transmission member 18 and the spherical plain bearing 36, the transmission member 18 is released from the spherical plain bearing 36 and is released from its attachment to the piston rod 9.

The transmission member 18 is removably connected to the spherical plain bearing 36 and attached to the piston rod 9, preventing the transmission member 18 from being easily damaged and allowing the extension and retraction stroke of the piston rod 9 to be appropriately transmitted to the control cylinder unit 19.

Figures 7 and 8 show other examples of the mounting structure of the transmission member 18 to the piston rod 9.

The piston rod 9 is provided with an annular sliding member 33 that surrounds its outer periphery and is slidable in the circumferential direction, and a pair of annular rings 34, 34 that are formed around the entire circumference of the piston rod 9 and have locking flanges 34a that clamp the annular sliding member 33 from both sides in the extension/contraction stroke direction (length direction) of the piston rod 9 to hold the annular sliding member 33 on the piston rod 9.

A mounting seat 35 is fixed to the annular sliding member 33 and is provided so as to be able to slide freely relative to the piston rod 9. A spherical plain bearing 36 is provided and supported by the mounting seat 35, and the base end 18a of the transmission member 18 is releasably connected to the spherical plain bearing 36.

The transmission member 18 is therefore attached at its base end 18a to the piston rod 9 via the spherical plain bearing 36 and the annular plain member 33.

The annular sliding member 33 slides against the outer circumference of the piston rod 9, preventing any torsional rotation that twists the piston rod 9 from acting on the mounting seat 35 or the transmission member 18.

The spherical plain bearing 36 is similar to the example in Figure 6, and transmits force to the transmission member 18 only in the direction of the extension stroke of the piston rod 9, cushioning and absorbing the various movements of the piston rod 9 relative to the transmission member 18 so that no load is applied from any other direction.

Also, similar to the above, when an excessive load is applied between the base end 18a of the transmission member 18 and the spherical plain bearing 36, the transmission member 18 is detached from the spherical plain bearing 36 and is released from its attachment to the piston rod 9.

The transmission member 18 is attached to the piston rod 9 by releasably connecting it to the spherical plain bearing 36, and is also attached to the piston rod 9 via the annular plain member 33, so that the transmission member 18 is prevented from being easily damaged and the extension and retraction stroke of the piston rod 9 can be appropriately transmitted to the control cylinder unit 19.

<<Improvement of the mounting portion 37 of the oil damper 4>>
As described above, the oil damper 4 is installed by connecting it to, for example, the ground 2 and the building 3, and as shown in Figures 2 and 3, mounting portions 37 for these objects are provided on the piston rod 9 and the outer cylinder 5 of the oil damper 4.

Figures 6 and 9 show enlarged views of the mounting portion 37 of the piston rod 9 in detail. The mounting portion 37 of the outer cylinder 5 has a similar structure.

As shown in the figure, the mounting portion 37 is composed of an end hardware 38 provided at the tip 9a of the piston rod 9 in the extension stroke direction or at the end of the outer cylinder 5, a connecting bracket 39 for connecting to a building 3 or the like, and a spherical plain bearing 40 provided between the connecting bracket 39 and the end hardware 38.

The spherical plain bearing 40 of the mounting portion 37 is also well known, and an axle pin 43 with a spherical portion 42 attached to the connecting bracket 39 is fitted into a clevis 41 attached to the end hardware 38, allowing tilting of the axle pin 43 around each axis in the axial direction (Z-axis direction), the length direction (Y-axis direction) of the piston rod 9 and outer cylinder 5, and the width direction (circumferential direction) (X-axis direction) of the piston rod 9 and outer cylinder 5.

The spherical plain bearing 40 allows the oil damper 4 to swing relative to the building 3 or other object to which it is connected, thereby flexibly maintaining the connection of the oil damper 4 to the building 3 or other object, and allowing the oil damper 4 to always operate properly.

<<Improvement of the support structure of the transmission member 18>>
2, 3, 10 and 11 show a support structure for the transmission member 18. The outer cylinder 5 of the oil damper 4 is provided with a suspender 45 having an eyebolt 44 at each of both ends 5a, 5b in its longitudinal direction (the extension and contraction stroke direction of the piston rod 9).

A flat base 46 is joined to the pair of hanging devices 45 to span between them and mount the pair of control cylinder units 19 described above.

The transmission member 18, which is sandwiched between a pair of control cylinder units 19 and disposed between them, is also supported movably on the base 46 at the position of the outer cylinder 5.

A hollow cylindrical protective tube 47 is provided on the base 46. The protective tube 47 is formed long in the extension stroke direction of the piston rod 9.

The protective tube 47 has both ends 47a attached to the base 46 via mounting brackets 48 at the positions of the pair of hanging devices 45.

The transmission member 18, including the operating part 24, is slidably inserted into this protective tube 47. In the illustrated example, the operating part 24 provided at the tip 18b of the transmission member 18 is formed in a disk shape that slides along the inner surface of the protective tube 47.

The protective tube 47 covers the transmission member 18 from the outside and guides the sliding direction of the transmission member 18 so that it does not deviate from the extension stroke direction of the piston rod 9.

The protective tube 47 has slits 49 formed on both sides facing the pair of control cylinder units 19, 19, which connect the inside and outside of the protective tube 47 and are at least as long as the extension stroke of the control piston rods 22, 22.

The passive parts 25, which are provided at the protruding ends of the pair of control piston rods 22, 22 and engage with the actuating part 24 to extend the control piston rods 22, 22, are provided with protrusions 50 that enable them to engage with the actuating part 24.

Each protrusion 50 is inserted through a slit 49 and protrudes inwardly into the protective tube 47 so that it can abut against the sliding actuating part 24. In the illustrated example, the protrusions 50 are formed outwardly from the passive part 25, which is formed in a disk shape.

When the protrusion 50 comes into contact with the operating part 24, the passive part 25 engages with the operating part 24, and the control piston rod 22 is extended by the excess extension stroke of the piston rod 9.

As shown in Figures 2 and 3, a bellows 51 that can expand and contract in response to the expansion and contraction stroke of the piston rod 9 is provided as a cover that covers the transmission member 18 from the outside, from the mounting seat 35 where the base end 18a of the transmission member 18 is attached and supported by the piston rod 9 to the mounting bracket 48 of the protective tube 47.

A protective tube 47 is provided into which the transmission member 18 including the operating part 24 is slidably inserted. By covering the transmission member 18 with the protective tube 47, it is possible to prevent the transmission member 18 from becoming soiled or contaminated by dust, etc., and the transmission member 18 can be smoothly slid.

In addition, the protective tube 47 is used to guide the sliding of the transmission member 18, so the sliding direction of the transmission member 18 can be prevented from deviating from the direction of the extension stroke of the piston rod 9, and the extension stroke of the piston rod 9 can be appropriately transmitted by the transmission member 18.

A slit 49 is formed in the protective tube 47, and a protrusion 50 is provided on the passive portion 25 of the pair of control piston rods 19, which protrudes into the protective tube 47 through the slit 49 and abuts against the operating portion 24. Therefore, even when the protective tube 47 is provided, the passive portion 25 can be engaged with the operating portion 24, and the excess extension stroke amount of the piston rod 9 can be reliably transmitted to the control piston rod 22.

The bellows 51 are provided to cover the transmission member 18 from the base end 18a of the transmission member 18 to the protective tube 47 from the outside, which prevents dust, moisture, water, etc. from adhering to the transmission member 18 exposed from the protective tube 47, and ensures the transmission of the extension and retraction stroke amount of the piston rod 9 by the sliding of the transmission member 18.

<<Improvement of the installation structure of the control cylinder unit 19>>
As shown in Figures 2 and 3, a pair of control cylinder units 19, 19, including a protective tube 47, are mounted on the base 46 and are configured as a control module that can be freely attached and detached to the outer cylinder 5 of the oil damper 4 simply by attaching and detaching the base 46.

As shown in FIG. 12, the base 46 is attached to the lifting device 45 by a breakable connector, such as a shear bolt 52. The shear bolt 52 is a well-known connector that breaks when a large shear force is applied.

The illustrated example shows the joint between the base 46 and the hanging device 45 at the mounting bracket 48 position, which attaches the protective tube 47 into which the transmission member 18 is inserted to the base 46, and the mounting bracket 48, base 46, and hanging device 45 are joined together by the shear bolt 52.

When the shear bolt 52 breaks, the transmission member 18 comes off the hanging device 45 and the base 46.

As shown in Figures 2, 3, and 13, a fixing member 53 for holding a pair of control cylinder units 19 is bolted to the base 46.

The fixing member 53 is a block body through which the pair of control cylinder units 19 and protective tube 47 pass, divided by a dividing line L that crosses the pair of control cylinder units 19 and protective tube 47 in a continuous manner, and is composed of a pair of block pieces 55 with a pair of bolt insertion holes 54 formed on both sides. These block pieces 55 are fastened with bolts to hold the control cylinder units 19 and protective tube 47.

A pair of control cylinder units 19, etc. are sandwiched between the pair of block pieces 55, and a nut 58 is fastened to a bolt 57 inserted into a bolt insertion hole 54 through a bolt hole 56 formed in the base 46, thereby bolting the pair of control cylinder units 19, etc. to the base 46.

In the illustrated example, the pair of control cylinder units 19 and the protective tube 47 are bolted to the base 46 with three fixing members 53 spaced apart along the length of the outer cylinder 5.

As shown in FIG. 14, the base 46 has a number of bolt holes 56 for bolting the fixing member 53 at a constant pitch along the length of the outer cylinder 5 so that the joining position of the fixing member 53 can be changed.

A base 46 is provided on which a pair of control cylinder units 19 and a protective tube 47 are mounted, and this base 46 is joined to the hanging device 45 of the outer cylinder 5. This allows the pair of control cylinder units 19, etc. to be a control module that can be attached and detached to the outer cylinder 5 of the oil damper 4 simply by attaching and detaching the base 46, improving the ease of assembly and maintenance of the oil damper system 1 according to this embodiment.

The base 46 is attached to the lifting device 45 with a breakable shear bolt 52, so that when a large shear force acts on the control module, the protective tube 47 and the control cylinder unit 19 can be protected and prevented from being damaged.

The base 46 has a number of bolt holes 56 for bolting the fixing members 53 so that the bolt-fastening position of the fixing members 53 that hold the pair of control cylinder units 19, etc. can be changed, so that the control cylinder units 19, etc. can be conveniently installed in a desired position.

LIST OF SYMBOLS 1 Oil damper system 2 Ground 3 Building 4 Uniflow type oil damper 5 Outer cylinder 7 Inner cylinder 8 Piston 9 Piston rod 10 Pressure regulating valve unit 13 Valve body 14 Valve element 15 Spring seat 16 Pressure regulating spring 18 Transmission member 18a Base end of transmission member 18b Tip end of transmission member 19 Control cylinder unit 20 Cylinder case 21 Control piston 22 Control piston rod 23 Spring 24 Actuating portion 25 Passive portion 26 Control oil distribution system 27 Communication portion 28 Check valve 29 Bypass path 30 Needle valve 33 Annular sliding member 36 Spherical plain bearing 40 Spherical plain bearing 45 Suspension device 46 Base 47 Protective tube 49 Slit 50 Protrusion 51 Bellows 52 Shear bolt 53 Fixing member 56 Bolt hole F Hydraulic oil f Control oil P3 Inlet port P4 Discharge port S Specified extension stroke amount

Claims (3)

a uniflow type oil damper having an outer cylinder connected to one of a vibration input side and a vibration damping target side, a piston rod connected to the other of the vibration input side and the vibration damping target side, and a pressure regulating valve unit that regulates and absorbs energy by opening a valve element biased by a pressure regulating spring at the outflow pressure of hydraulic oil flowing out of the inner cylinder due to the movement of the piston;
a transmission member that transmits an extension stroke amount of the piston rod that moves the piston;
a pair of control cylinder units each provided along the extension stroke direction of the piston rod, the control cylinder units having a cylinder case filled with control oil and a control piston that discharges the control oil in the cylinder case from a discharge port when the control piston rod is extended, the control piston rod is extended by the transmission member by the excess extension stroke amount or excess contraction stroke amount when an excess extension stroke or excess contraction stroke amount that exceeds a predetermined extension stroke amount occurs in the piston rod, and the control cylinder units discharge the control oil from the discharge port,
a control oil flow system having a communication part that communicates the discharge ports of the pair of control cylinder units with each other and connecting the communication part with an introduction port of the pressure regulating valve unit,
the pressure regulating valve unit includes a valve body having the introduction port, the pressure regulating spring provided within the valve body, the valve element provided within the valve body and opened by the outflow pressure of hydraulic oil resisting the spring force of the pressure regulating spring, and a spring seat provided within the valve body and moved so as to compress the pressure regulating spring by the hydraulic pressure of control oil introduced from the introduction port,
a check valve disposed in the control oil distribution system between the communicating portion and the introduction port of the pressure regulating valve unit, for introducing the control oil into the introduction port when the hydraulic pressure of the control oil from one of the control cylinder units exceeds a valve opening pressure by the action of the hydraulic pressure of the control oil from the spring seat, and for allowing the control oil to flow into the discharge port of the other of the control cylinder units via the communicating portion when the hydraulic pressure of the control oil from the other of the control cylinder units is equal to or lower than the valve opening pressure,
The spring force of the pressure adjusting spring is changed according to the amount of excess extension stroke or the amount of excess contraction stroke,
An oil damper system characterized in that a pair of hanging devices are provided at both longitudinal ends of the outer cylinder, and a base for mounting the pair of control cylinder units is connected between these hanging devices. The oil damper system according to claim 1, characterized in that the base is attached to the hanging device with a breakable connector to protect the transmission member. The oil damper system according to claim 1 or 2, characterized in that a fixing member for holding the pair of control cylinder units is bolted to the base, and a number of bolt holes for bolting the fixing member are formed so that the joining position of the fixing member can be changed.

Images