JP2019178764A - Damper for base isolation - Google Patents

Abstract

To provide a damper for base isolation capable of easily making damping force characteristics in an expansion operation and a contraction operation easily agree with each other even when damping force depending on displacement can be exerted.SOLUTION: A damper D for base isolation includes a second expansion-side damping valve 15 disposed on an expansion-side bypass passage 8 corresponding to a first expansion-side damping valve 11 disposed on an expansion-side damping passage 4, a second pressure-side damping valve 16 disposed on a pressure-side bypass passage 9 corresponding to a first pressure-side damping valve 12 disposed on a pressure-side damping passage 5, and a second base valve 17 disposed on a discharge-side bypass passage 10 corresponding to a first base valve 13 disposed on a discharge passage 6. The expansion-side bypass passage 8, the pressure-side bypass passage 9 and the discharge-side bypass passage 10 are made effective only in a case when a piston 2 is positioned within a prescribed range to a cylinder 1.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a seismic isolation damper.

  The seismic isolation device is equipped with seismic isolation devices such as ball isolators and laminated rubber that are interposed between the ground and the structure, and supports the structure so that it can move with respect to the ground. Insulate transmission to things. The seismic isolation bearing device may include a seismic isolation damper interposed between the ground and the structure in addition to the seismic isolation bearing device as described above. Damping with the damping force generated by the seismic isolation damper suppresses the vibration of the structure.

  In the seismic isolation bearing device, the smaller the damping force of the seismic isolation damper when an earthquake occurs, the less likely it is to transmit ground vibrations to the building, thus ensuring high vibration insulation. On the other hand, the seismic isolation bearing device suppresses the movement of the structure by the damping force generated by the seismic isolation damper for large-scale ground motions where the structure moves with large amplitude relative to the ground. It is necessary to avoid the falling off of the structure from the support device and the collision between the structure and the retaining wall surrounding the lower end of the structure.

  Therefore, in the seismic isolation bearing device, the damping force is not exhibited as much as possible to the large amplitude vibration so as not to impair the vibration insulation of the seismic isolation device for small amplitude vibration. Therefore, it is preferable to make the seismic isolation damper positively exert a damping force.

  In order to meet such demands, seismic isolation dampers that can change the damping force depending on the displacement have been proposed. In such seismic isolation dampers, a mechanism for transmitting the displacement of the damper to the valve is proposed. Is installed outside the cylinder, and the valve is driven by the mechanism to open and close the flow path to change the damping force. Therefore, in this seismic isolation damper, since the block having the flow path provided with the valve outside the cylinder and the mechanism are provided, the block and the mechanism interfere with other parts when installed on the building. There is a possibility, and it gets in the way during transportation.

  In order to solve this problem, without providing an external mechanism, there are two holes that pass through the cylinder, a bypass path that connects the holes and bypasses the damping valve provided in the piston, and a passage of the piston in the passage. There has been developed a seismic isolation damper that is provided with a valve that opens and closes a passage according to the moving speed with respect to the cylinder and changes the damping force depending on the displacement of the piston with respect to the cylinder without providing a mechanism outside (for example, Patent Documents) 1).

  In this conventional seismic isolation damper, when the piston is in the center side sliding range with respect to the cylinder, the bypass path functions effectively to reduce the damping force, and even if the bypass path is effective, the piston When the moving speed becomes high, the valve blocks the bypass and does not reduce the damping force.

JP 2017-96433 A

  However, such a seismic isolation damper that does not require an external mechanism is a single rod type in which the rod is inserted only into the extension side chamber, so that when the cylinder contracts, the pressure in the cylinder rises by the base valve. In addition, the damping force is exhibited in proportion to the increase in the cylinder pressure.

  However, the seismic isolation damper has only a bypass path that bypasses only the damping valve provided on the piston and can function as a bypass path during extension operation to reduce the damping force. The function of the road will be halved. Therefore, in the conventional seismic isolation damper, it is difficult to match the damping force characteristics between the extension operation and the contraction operation.

  Therefore, an object of the present invention is to provide a seismic isolation damper that can easily match the damping force characteristics during the extension operation and the contraction operation even if the damping force depending on the displacement can be exhibited.

  In order to achieve the above-described object, the seismic isolation damper of the present invention includes a cylinder, a piston that is slidably inserted into the cylinder and divides the cylinder into an extension side chamber and a pressure side chamber, and is inserted into the cylinder. And a rod whose one end is connected to the piston, a tank for storing liquid, an extension side damping passage and a pressure side damping passage communicating the extension side chamber and the pressure side chamber, and a discharge passage and suction connecting the pressure side chamber and the tank. A first extension side damping valve that is provided in the passage, provided in the extension side damping passage, allows only the flow of liquid from the extension side chamber to the pressure side chamber, and provides resistance to the flow of liquid passing therethrough, and provided in the pressure side attenuation passage. A first pressure side damping valve that allows only the flow of liquid from the pressure side chamber to the extension side chamber and provides resistance to the flow of liquid passing through, and a liquid that is provided in the discharge passage and is directed to the tank from the pressure side chamber 1st base valve that allows only flow and resistance to the flow of liquid that passes through, a check valve that is provided in the suction passage and only allows flow of liquid from the tank to the pressure side chamber, and is set on the center side of the cylinder Only when the piston is positioned within a predetermined range, the extension side bypass passage and the pressure side bypass passage communicating the extension side chamber and the compression side chamber, and only when the piston is on the extension side chamber side including the predetermined range with respect to the cylinder A discharge side bypass passage that communicates the pressure side chamber and the tank, and a second extension side that is provided in the extension side bypass passage and allows only the flow of liquid from the extension side chamber to the pressure side chamber and provides resistance to the flow of liquid passing therethrough The moving speed of the piston toward the extension side chamber with respect to the cylinder when the extension side bypass passage is connected to the extension side chamber and the compression side chamber. An extension-side speed-dependent opening / closing valve that shuts off the extension-side bypass passage when the pressure exceeds a predetermined speed, and that is provided in the pressure-side bypass passage and allows only the flow of liquid from the compression-side chamber to the extension-side chamber and resists the flow of liquid passing therethrough When the pressure side bypass passage is connected to the pressure side chamber and the extension side chamber, the moving speed of the piston to the pressure side chamber side with respect to the cylinder exceeds a predetermined speed. A pressure-side speed-dependent opening / closing valve that shuts off the pressure-side bypass path; a second base valve that is provided in the discharge-side bypass path and that allows only the flow of liquid from the pressure-side chamber to the tank and provides resistance to the flow of liquid that passes through; When the discharge-side bypass passage is provided in the discharge-side bypass passage and communicates the pressure-side chamber and the tank, the piston moves to the pressure-side chamber side with respect to the cylinder. A discharge-side speed-dependent on-off valve that shuts off the discharge-side bypass when the dynamic speed exceeds a predetermined speed, and the cylinder when the discharge-side bypass connects the pressure-side chamber and the tank. A discharge side opening / closing valve that opens the discharge side bypass passage only when the piston moves to the pressure side chamber side is provided.

  In the seismic isolation damper configured as described above, when each bypass passage is activated, the second expansion side damping valve is set to the first extension side damping valve, and the second pressure side damping valve is set to the first pressure side damping valve. However, the second base valve functions effectively with respect to the first base valve. Therefore, when the seismic isolation damper is contracted, if the piston is located within a predetermined range with respect to the cylinder and the moving speed of the piston is lower than the predetermined speed, not only the first base valve but also the second base valve Since the liquid can be discharged from the cylinder to the tank through, the damping force during the contraction operation can be reduced as compared with the conventional seismic isolation damper.

  Therefore, according to the seismic isolation damper of the present invention, it is possible to easily match the damping force characteristics between the extension operation and the contraction operation even if the damping force depending on the displacement can be exhibited.

It is a side view in the state where the seismic isolation damper in one embodiment was interposed between the structure and the ground together with the seismic isolation support device. It is sectional drawing of the damper for seismic isolation in one Embodiment. It is a circuit diagram of the seismic isolation damper in one embodiment. It is the figure which showed the characteristic of the damping force with respect to the moving speed of the piston of the seismic isolation damper in one Embodiment.

  The present invention will be described below based on the embodiments shown in the drawings. As shown in FIG. 1, the seismic isolation damper D according to the embodiment is interposed between the structure S and the ground G together with the seismic isolation support device M that is horizontally placed and made of laminated rubber. . In addition, as the seismic isolation bearing device M, it is possible to adopt a device capable of allowing horizontal movement of the structure S such as a ball isolator in addition to the laminated rubber.

  As shown in FIG. 2, the seismic isolation damper D includes a cylinder 1, a piston 2 that is slidably inserted into the cylinder 1 and divides the cylinder 1 into an extension side chamber R <b> 1 and a compression side chamber R <b> 2, A rod 3 inserted into the cylinder 1 and connected at one end to the piston 2, a tank T for storing liquid, an extension side damping passage 4 and a pressure side damping passage 5 communicating the extension side chamber R1 and the pressure side chamber R2, A discharge passage 6 and a suction passage 7 that connect the pressure side chamber R2 and the tank T, an extension side bypass passage 8 and a pressure side bypass passage 9 that connect the extension side chamber R1 and the pressure side chamber R2, and the pressure side chamber R2 and the tank T. The discharge side bypass passage 10, the first expansion side damping valve 11, the first pressure side damping valve 12, the first base valve 13, the check valve 14, the second expansion side damping valve 15, the second pressure side damping valve 16, Two base bar Bed 17, the extension side speed-dependent opening and closing valve 18, the compression side speed-dependent opening and closing valve 19 is constituted by a discharge-side speed-dependent opening and closing valve 20 and the discharge-side opening and closing valve 21.

  The extension side chamber R1 and the pressure side chamber R2 are each filled with hydraulic fluid as a liquid, and the tank T is filled with hydraulic fluid and gas as a liquid. In this example, the liquid is hydraulic oil, but may be other liquid such as water or an aqueous solution. The gas may be an inert gas such as nitrogen that does not cause deterioration of the hydraulic oil, but other gases such as the atmosphere can be used.

  Hereinafter, each part of the seismic isolation damper D will be described in detail. A valve case 22 is fitted to one end of the cylinder 1 and a rod guide 23 is fitted to the other end. An outer cylinder 24 that covers the outer periphery of the cylinder 1 and forms a tank T with an annular gap between the cylinder 1 is provided outside the cylinder 1. One end of the outer cylinder 24 is closed by a cap 25, and the other end of the outer cylinder 24 is closed by a rod guide 23. The cylinder 1 is sandwiched between a rod guide 23 attached to the outer cylinder 24 and a valve case 22 that comes into contact with the cap 25 and is fixed while being accommodated in the outer cylinder 24. Therefore, the left end of the cylinder 1 in FIG. 2 is closed by the rod guide 23, and the right end of the cylinder 1 in FIG. 2 is closed by the valve case 22.

  The piston 2 is slidably inserted into the cylinder 1 and divides the cylinder 1 into an extension side chamber R1 and a compression side chamber R2, and a seismic isolation damper D is provided between the structure S and the ground G. Is positioned at a neutral position, which is the center of the cylinder 1. Although the neutral position is not limited to the center of the cylinder 1, in the seismic isolation damper D, the movement distance from the neutral position of the piston 2 to the stroke limit is generally the same on both the expansion side and the contraction side. Is set as follows.

  One end of the rod 3 is movably inserted into the cylinder 1 through the rod guide 23 and connected to the piston 2, and the other end projects out of the cylinder 1. Therefore, the seismic isolation damper D is a so-called single rod type damper in which the rod 3 is inserted only into the extension side chamber R1.

  The cap 25 is provided with a bracket 25a connected to the attachment portion Bs provided in the structure S, and the other end of the rod 3 is provided with a bracket 3a connected to the attachment portion Bg provided on the ground G. The seismic isolation damper D can be installed between the structure S and the ground G by the brackets 3a and 25a.

  In the present embodiment, the piston 2 includes an extension side damping passage 4 and a pressure side damping passage 5 that communicate the extension side chamber R1 and the compression side chamber R2, and a first extension side damping valve provided in the extension side damping passage 4. 11 and a first pressure side damping valve 12 provided in the pressure side damping passage 5.

  The first extension side damping valve 11 allows only the flow of hydraulic fluid from the extension side chamber R1 to the compression side chamber R2, and gives resistance to the flow of hydraulic fluid that passes therethrough. More specifically, in the present embodiment, the first expansion side damping valve 11 is a pressure regulating valve as shown in FIG. 3, and when the passing flow rate reaches a predetermined flow rate, the pressure loss increases with respect to the flow rate increase. It has the characteristic that the ratio decreases.

  The first pressure-side damping valve 12 allows only the flow of hydraulic fluid from the compression-side chamber R2 to the expansion-side chamber R1, and gives resistance to the flow of hydraulic fluid that passes through. More specifically, the first pressure side damping valve 12 is a pressure regulating valve in the present embodiment, similarly to the first expansion side damping valve 11, and when the passing flow rate reaches a predetermined flow rate, the pressure loss with respect to the flow rate increase. It has the characteristic that the increase rate of decreases.

  The valve case 22 divides the inside of the cylinder 1 and the tank T, and includes a discharge passage 6 and a suction passage 7 that connect the pressure side chamber R2 and the tank T, and a first base provided in the discharge passage 6. A valve 13 and a check valve 14 provided in the suction passage 7 are provided.

  The first base valve 13 allows only the flow of the hydraulic oil from the pressure side chamber R2 to the tank T and gives resistance to the flow of the hydraulic oil passing therethrough. More specifically, the first base valve 13 is a pressure regulating valve in the present embodiment, similarly to the first expansion side damping valve 11, and when the passing flow rate reaches a predetermined flow rate, the pressure loss with respect to the flow rate increase is reduced. It has the characteristic that the increase rate decreases. Further, the check valve 14 is a one-way passage that allows only the flow of hydraulic oil from the pressure side chamber R2 to the tank T and allows only the flow of hydraulic oil from the tank T to the pressure side chamber R2. It is set.

  The cylinder 1 has holes 1a and 1b arranged in the same circumferential direction on the left side in FIG. 2 from the center, and holes 1c and 1d arranged in the same circumferential direction on the right side in FIG. 2 from the center. And has. And the hole 1a and the hole 1c are connected by the expansion side bypass path 8 accommodated in the tank T, and the hole 1b and the hole 1d are connected by the pressure side bypass path 9 accommodated in the tank T. .

  When the piston 2 is located between the holes 1a and 1b and the holes 1c and 1d with respect to the cylinder 1, the holes 1a and 1b communicate with the expansion side chamber R1, and the holes 1c and 1d communicate with the compression side chamber R2. Therefore, when the piston 2 is located between the holes 1a, 1b and the holes 1c, 1d with respect to the cylinder 1, the extension side bypass path 8 and the pressure side bypass path 9 communicate the extension side chamber R1 and the pressure side chamber R2. . On the other hand, when the left end in FIG. 2 of the piston 2 is located on the left side in FIG. 2 with respect to the left end in FIG. 2 of the holes 1a and 1b, the holes 1a and 1b are closed by the piston 2, or All of 1b, 1c, 1d will be in the state which leads only to compression side chamber R2. Therefore, in this case, the extension side bypass path 8 and the pressure side bypass path 9 are in a state where the extension side chamber R1 and the pressure side chamber R2 cannot communicate with each other. Further, when the right end in FIG. 2 of the piston 2 is located on the right side in FIG. 2 with respect to the right end in FIG. 2 of the holes 1c and 1d, the holes 1c and 1d are closed by the piston 2 or the holes 1a, 1b and 1c. , 1d is in a state that leads to only the extension side chamber R1. Therefore, in this case, the extension side bypass path 8 and the pressure side bypass path 9 are in a state where the extension side chamber R1 and the pressure side chamber R2 cannot communicate with each other.

  In this way, the extension side bypass passage 8 and the pressure side bypass passage 9 are provided only when the piston 2 is located between the holes 1a, 1b and the holes 1c, 1d with respect to the cylinder 1, that is, at the center side of the cylinder 1. Only when the piston 2 is positioned within the predetermined range, the extension side chamber R1 and the compression side chamber R2 are communicated. That is, the predetermined range set in the cylinder 1 in which the expansion side bypass path 8 and the pressure side bypass path 9 communicate with the expansion side chamber R1 and the compression side chamber R2 is a position where these holes 1a, 1b, 1c, 1d are provided. Set by When the piston 2 is positioned on both the left and right sides in FIG. 2 beyond a predetermined range set on the center side of the cylinder 1, the extension side bypass path 8 and the pressure side bypass path 9 are connected to the extension side chamber R1 and the pressure side chamber R2. It will be in the state which does not communicate with.

  The extension side bypass passage 8 includes a second extension side damping valve 15 and an extension side speed-dependent opening / closing valve 18 that allow only the flow of liquid from the extension side chamber R1 to the compression side chamber R2 and provide resistance to the flow of liquid that passes therethrough. Is provided. The second extension side damping valve 15 and the extension side speed-dependent opening / closing valve 18 are mounted on the outer periphery of the cylinder 1 as shown in FIG. The second extension side damping valve 15 allows only the flow of hydraulic oil from the extension side chamber R1 to the compression side chamber R2, and gives resistance to the flow of hydraulic oil passing therethrough. More specifically, in the present embodiment, the second expansion side damping valve 15 is a pressure regulating valve as shown in FIG. 3, and when the passing flow rate reaches a predetermined flow rate, an increase in pressure loss with respect to an increase in flow rate is achieved. Compared with the first expansion side damping valve 11, the pressure loss with respect to the passage of hydraulic oil of the same flow rate is small.

  Further, as shown in FIG. 3, the extension side speed-dependent opening / closing valve 18 includes a communication position for opening the extension side bypass path 8 and a blocking position for blocking the extension side bypass path 8, and includes upstream pressure and downstream side. It opens and closes according to the pressure difference. More specifically, the extension side speed-dependent opening / closing valve 18 is a normally open type opening / closing valve that functions as an orifice in the communication position and closes when the flow rate increases and the differential pressure between the upstream side and the downstream side increases. In a state where the expansion side bypass passage 8 effectively communicates the expansion side chamber R1 and the compression side chamber R2, when the moving speed of the piston 2 with respect to the cylinder 1 toward the expansion side chamber R1 on the left side in FIG. Since the flow rate passing through the side speed dependent opening / closing valve 18 increases, the extension side speed dependent opening / closing valve 18 is closed. Thus, the extension side speed-dependent opening / closing valve 18 opens and closes depending on the moving speed of the piston 2 relative to the cylinder 1 during the extension operation of the seismic isolation damper D.

  The pressure-side bypass 9 is provided with a second pressure-side damping valve 16 and a pressure-side speed-dependent opening / closing valve 19 that allow only the flow of liquid from the pressure-side chamber R2 to the extension-side chamber R1 and provide resistance to the flow of liquid that passes through. ing. As shown in FIG. 2, the second pressure side damping valve 16 and the pressure side speed-dependent opening / closing valve 19 are mounted on the outer periphery of the cylinder 1 and are accommodated in the tank T. The second pressure side damping valve 16 allows only the flow of hydraulic fluid from the compression side chamber R2 toward the expansion side chamber R1, and provides resistance to the flow of hydraulic fluid passing therethrough. More specifically, as shown in FIG. 3, the second pressure side damping valve 16 is a pressure regulating valve, and when the passing flow rate reaches a predetermined flow rate, the rate of increase in pressure loss with respect to the flow rate increase. And a characteristic that the pressure loss with respect to the passage of the hydraulic oil of the same flow rate is small as compared with the first pressure side damping valve 12.

  Further, as shown in FIG. 3, the pressure-side speed-dependent opening / closing valve 19 includes a communication position for opening the pressure-side bypass path 9 and a blocking position for blocking the pressure-side bypass path 9 so that the pressure on the upstream side and the pressure on the downstream side are reduced. Open and close according to the difference. More specifically, the pressure-side speed-dependent on-off valve 19 is a normally open type on-off valve that functions as an orifice in the communication position and closes when the flow rate increases and the differential pressure between the upstream side and the downstream side increases. When the pressure side bypass passage 9 effectively communicates the pressure side chamber R2 and the expansion side chamber R1, when the moving speed of the piston 2 relative to the cylinder 1 to the pressure side chamber R2 side in FIG. Since the flow rate passing through the dependent opening / closing valve 19 increases, the pressure side speed dependent opening / closing valve 19 is closed. In this way, the compression-side speed-dependent opening / closing valve 19 opens and closes depending on the moving speed of the piston 2 relative to the cylinder 1 when the seismic isolation damper D is in the contracting operation.

  Further, the hole 1 d provided in the cylinder 1 communicates with the tank T through the discharge side bypass passage 10. When the piston 2 is located with respect to the cylinder 1 such that the right end of the piston 2 in FIG. 2 is to the left of FIG. 2 than the right end of FIG. 2 of the hole 1d, the hole 1d communicates with the pressure side chamber R2. The bypass path 10 communicates the pressure side chamber R2 and the tank T. That is, the discharge-side bypass passage 10 communicates the pressure-side chamber R2 and the tank T only when the piston 2 is on the extension-side chamber R1 side including a predetermined range with respect to the cylinder 1. On the other hand, when the right end in FIG. 2 of the piston 2 is located on the right side in FIG. 2 from the right end in FIG. 2 of the hole 1d, that is, on the pressure side chamber R2 side with respect to the cylinder 1 from the predetermined range. Then, the hole 1d is blocked by the piston 2, or the hole 1d is communicated with the expansion side chamber R1, so that the discharge side bypass passage 10 cannot communicate with the pressure side chamber R2 and the tank T. Thus, the pressure side bypass 9 communicates the pressure side chamber R2 and the tank T only when the piston 2 is located on the expansion side chamber R1 side including the predetermined range with respect to the cylinder 1.

  In the discharge-side bypass path 10, a second base valve 17, a discharge-side speed-dependent opening / closing valve 20, and a discharge-side opening / closing that allow only the flow of liquid from the pressure-side chamber R2 to the tank T and provide resistance to the flow of liquid passing therethrough. A valve 21 is provided. As shown in FIG. 2, the second base valve 17, the discharge side speed-dependent opening / closing valve 20, and the discharge side opening / closing valve 21 are mounted on the outer periphery of the cylinder 1 and accommodated in the tank T. The second base valve 17 allows only the flow of hydraulic oil from the compression side chamber R2 to the tank T and gives resistance to the flow of hydraulic oil passing therethrough. More specifically, in the present embodiment, the second base valve 17 is a pressure regulating valve as shown in FIG. 3, and when the passing flow rate reaches a predetermined flow rate, the rate of increase in pressure loss with respect to the increase in flow rate is increased. Compared to the first base valve 13, the pressure loss with respect to the passage of the same amount of hydraulic oil is small.

  Further, as shown in FIG. 3, the discharge-side speed-dependent opening / closing valve 20 includes a communication position for opening the discharge-side bypass path 10 and a blocking position for blocking the discharge-side bypass path 10, and has an upstream pressure and a downstream side. It opens and closes according to the pressure difference. More specifically, the discharge-side speed-dependent on-off valve 20 is a normally open type on-off valve that functions as an orifice in the communication position and closes when the flow rate increases and the differential pressure between the upstream side and the downstream side increases. In a state where the discharge side bypass passage 10 effectively communicates the pressure side chamber R2 and the tank T, when the moving speed of the piston 2 relative to the cylinder 1 to the pressure side chamber R2 side in FIG. Since the flow rate passing through the speed-dependent opening / closing valve 20 increases, the discharge-side speed-dependent opening / closing valve 20 is closed. Thus, the discharge side speed-dependent opening / closing valve 20 opens and closes depending on the moving speed of the piston 2 with respect to the cylinder 1 when the seismic isolation damper D is in the contracting operation.

  Further, as shown in FIG. 3, the discharge side opening / closing valve 21 includes a communication position for opening the discharge side bypass path 10 and a blocking position for blocking the discharge side bypass path 10, so that the pressure of the hole 1 b and the hole 1 d Opens and closes according to the pressure difference. More specifically, the discharge-side opening / closing valve 21 is a normally closed opening / closing valve that opens when the pressure in the hole 1d becomes greater than the pressure in the hole 1b.

  When the piston 2 is located on the expansion side chamber R1 side with respect to the cylinder 1 with respect to the cylinder 1, both the holes 1b and 1d are communicated with the pressure side chamber R2, and therefore the pressures in both the holes 1b and 1d are equal. The discharge side opening / closing valve 21 maintains a closed state.

  When the piston 2 is positioned within a predetermined range with respect to the cylinder 1, the hole 1b is communicated with the expansion side chamber R1, and the hole 1d is communicated with the compression side chamber R2. In this state, when the piston 2 moves toward the expansion side chamber R1 with respect to the cylinder 1, the pressure in the hole 1b becomes higher than the pressure in the hole 1d, so the discharge side opening / closing valve 21 maintains the closed state. In this state, when the piston 2 moves toward the pressure side chamber R2 with respect to the cylinder 1, the pressure in the hole 1d becomes higher than the pressure in the hole 1b, so that the discharge side opening / closing valve 21 is opened.

  Further, when the piston 2 is positioned on the pressure side chamber R2 side with respect to the cylinder 1, the holes 1b and 1d are both communicated with the expansion side chamber R1, so that the pressures in both the holes 1b and 1d are equal. Therefore, the discharge side opening / closing valve 21 maintains the closed state.

  That is, the discharge-side opening / closing valve 21 is provided only when the piston 2 moves to the pressure-side chamber R2 side with respect to the cylinder 1 when the discharge-side bypass passage 10 communicates the pressure-side chamber R2 and the tank T. 10 is released.

  The seismic isolation damper D is configured as described above, and its operation will be described below. First, when the seismic isolation damper D exhibits an extension operation in a state where the piston 2 is located within a predetermined range with respect to the cylinder 1, the extension side damping passage 4 and the extension side bypass passage 8 provided in the piston 2 function effectively. To do. When the movement speed of the piston 2 during the extension operation of the seismic isolation damper D is lower than a predetermined speed, the expansion side speed-dependent opening / closing valve 18 opens, so that the expansion side chamber R1 compressed by the movement of the piston 2 is opened. The hydraulic oil heading toward the expanding pressure side chamber R2 can pass through both the first extension side damping valve 11 and the second extension side damping valve 15. On the other hand, when the movement speed of the piston 2 during the extension operation of the seismic isolation damper D is equal to or higher than a predetermined speed, the expansion side speed-dependent opening / closing valve 18 is closed, so that the expansion side chamber compressed by the movement of the piston 2 is closed. The hydraulic oil heading from R1 toward the pressure side chamber R2 passes only through the first extension side damping valve 11. Therefore, when the seismic isolation damper D exhibits an extension operation in a state where the piston 2 is located within a predetermined range with respect to the cylinder 1, the seismic isolation damper D has a movement speed of the piston 2 of a predetermined speed or more. A large damping force is exhibited as indicated by the inner line L1, and a small damping force is exhibited as indicated by the line L2 in FIG. 4 when the moving speed of the piston 2 is lower than the predetermined speed. That is, the seismic isolation damper D changes the damping force according to the moving speed of the piston 2. During the extension operation of the seismic isolation damper D, the volume of hydraulic oil that allows the rod 3 to retreat from the cylinder 1 through the suction passage 7 is supplied from the tank T into the cylinder 1 to perform volume compensation during the extension operation.

  Subsequently, when the seismic isolation damper D exhibits a contraction operation in a state where the piston 2 is located within a predetermined range with respect to the cylinder 1, the compression side damping passage 5, the pressure side bypass passage 9 and the discharge side bypass passage provided in the piston 2. 10 functions effectively. When the moving speed of the piston 2 during the contraction operation of the seismic isolation damper D is lower than a predetermined speed, the pressure side speed-dependent opening / closing valve 19, the discharge side speed dependent opening / closing valve 20, and the discharge side opening / closing valve 21 are opened. The hydraulic fluid from the pressure side chamber R2 compressed by the movement of the piston 2 toward the expansion side chamber R1 can pass through both the first pressure side damping valve 12 and the second pressure side damping valve 16. Further, the volume of hydraulic oil into which the rod 3 enters the cylinder 1 passes through the first base valve 13 and the second base valve 17 from the cylinder 1 and is discharged to the tank T. On the other hand, when the moving speed of the piston 2 during the contraction movement of the seismic isolation damper D exceeds a predetermined speed, the pressure-side speed-dependent opening / closing valve 19 and the discharge-side speed-dependent opening / closing valve 20 are closed. The hydraulic fluid heading from the compression side chamber R2 compressed by the movement to the expansion side chamber R1 passes only through the first compression side damping valve 12, and the hydraulic fluid discharged from the cylinder 1 to the tank T is only the first base valve 13. Pass through. Therefore, when the seismic isolation damper D exhibits a contraction operation in a state where the piston 2 is located within a predetermined range with respect to the cylinder 1, the seismic isolation damper D has a movement speed of the piston 2 equal to or higher than the predetermined speed. A large damping force is exerted as shown by the middle line L3, and if the moving speed of the piston 2 is lower than the predetermined speed, a small damping force is exerted as shown by the line L4 in FIG. That is, the seismic isolation damper D changes the damping force according to the moving speed of the piston 2.

  Furthermore, when the piston 2 is positioned on the extension side chamber R1 side with respect to the cylinder 1 from the predetermined range and the seismic isolation damper D exhibits the extension operation, the extension side bypass passage 8 passes only through the compression side chamber R2 and is attenuated on the extension side. It cannot function as a bypass route that bypasses the passage 4. Regardless of the moving speed of the piston 2 during the extension operation of the seismic isolation damper D, the hydraulic oil heading from the expansion side chamber R1 compressed by the movement of the piston 2 to the expanding pressure side chamber R2 is the first extension side damping valve. Pass only 11 Therefore, when the seismic isolation damper D exhibits the extension operation in a state where the piston 2 is located on the extension side chamber R1 side with respect to the cylinder 1 with respect to the cylinder 1, the seismic isolation damper D is indicated by a line L1 in FIG. So as to exert a great damping force. During the extension operation of the seismic isolation damper D, the volume of hydraulic oil that allows the rod 3 to retreat from the cylinder 1 through the suction passage 7 is supplied from the tank T into the cylinder 1 to perform volume compensation during the extension operation.

  Further, when the seismic isolation damper D exhibits a contraction operation in a state where the piston 2 is located on the extension side chamber R1 side from the predetermined range from the neutral position with respect to the cylinder 1, the compression side bypass passage 9 leads only to the compression side chamber R2. It cannot function as a bypass path that bypasses the compression side attenuation path 5. Further, the discharge-side bypass path 10 is blocked because the discharge-side opening / closing valve 21 is closed, and cannot function as a bypass path that bypasses the discharge path 6. Therefore, regardless of the moving speed of the piston 2 during the contraction operation of the seismic isolation damper D, the hydraulic oil heading from the compression side chamber R2 compressed by the movement of the piston 2 to the expanding side chamber R1 is the first pressure side damping valve. The hydraulic oil of a volume that passes through only 12 and the rod 3 enters the cylinder 1 passes only through the first base valve 13. Therefore, when the seismic isolation damper D exhibits a contraction operation in a state where the piston 2 is located on the extension side chamber R1 side with respect to the cylinder 1 with respect to the cylinder 1, the seismic isolation damper D is indicated by a line L3 in FIG. So as to exert a great damping force. During the extension operation of the seismic isolation damper D, the volume of hydraulic oil that allows the rod 3 to retreat from the cylinder 1 through the suction passage 7 is supplied from the tank T into the cylinder 1 to perform volume compensation during the extension operation.

  When the piston 2 is located on the compression side chamber R2 side with respect to the cylinder 1 from the predetermined range and the seismic isolation damper D exhibits an extension operation, the extension side bypass passage 8 passes through only the extension side chamber R1 and extends to the extension side. It cannot function as a bypass route that bypasses the passage 4. Regardless of the moving speed of the piston 2 during the extension operation of the seismic isolation damper D, the hydraulic oil heading from the expansion side chamber R1 compressed by the movement of the piston 2 to the expanding pressure side chamber R2 is the first extension side damping valve. Pass only 11 Therefore, when the seismic isolation damper D exhibits the extension operation in a state where the piston 2 is located on the extension side chamber R1 side with respect to the cylinder 1 with respect to the cylinder 1, the seismic isolation damper D is indicated by a line L1 in FIG. So as to exert a great damping force. During the extension operation of the seismic isolation damper D, the volume of hydraulic oil that allows the rod 3 to retreat from the cylinder 1 through the suction passage 7 is supplied from the tank T into the cylinder 1 to perform volume compensation during the extension operation.

  Further, when the seismic isolation damper D exhibits a contraction operation in a state where the piston 2 is positioned on the expansion side chamber R1 side from the neutral position with respect to the cylinder 1, the compression side bypass passage 9 leads only to the expansion side chamber R1. It cannot function as a bypass path that bypasses the compression side attenuation path 5. Further, the discharge-side bypass path 10 is blocked because the discharge-side opening / closing valve 21 is closed, and cannot function as a bypass path that bypasses the discharge path 6. Therefore, regardless of the moving speed of the piston 2 during the contraction operation of the seismic isolation damper D, the hydraulic oil heading from the compression side chamber R2 compressed by the movement of the piston 2 to the expanding side chamber R1 is the first pressure side damping valve. The hydraulic oil of a volume that passes through only 12 and the rod 3 enters the cylinder 1 passes only through the first base valve 13. Therefore, when the seismic isolation damper D exhibits a contraction operation in a state where the piston 2 is located on the extension side chamber R1 side with respect to the cylinder 1 with respect to the cylinder 1, the seismic isolation damper D is indicated by a line L3 in FIG. So as to exert a great damping force. During the extension operation of the seismic isolation damper D, the volume of hydraulic oil that allows the rod 3 to retreat from the cylinder 1 through the suction passage 7 is supplied from the tank T into the cylinder 1 to perform volume compensation during the extension operation.

  Further, when the seismic isolation damper D exhibits an extension operation and the piston 2 moves from the neutral position to the cylinder 1 with the predetermined range exceeding the predetermined range, the expansion side bypass is provided when the piston 2 exceeds the predetermined range. The state in which the path 8 is functioning effectively is switched to the invalid state. If the moving speed of the piston 2 during the extension operation of the seismic isolation damper D is lower than the predetermined speed, the second expansion side damping valve 15 is closed when the piston 2 exceeds the predetermined range toward the expansion side chamber R1. In order to produce such an effect, the damping force of the seismic isolation damper D transitions from the line L2 in FIG. 4 to the line L2 as indicated by a broken line arrow. On the other hand, when the moving speed of the piston 2 during the extension operation of the seismic isolation damper D is equal to or higher than the predetermined speed, the extension side speed-dependent opening / closing valve 18 is closed, so that the damping force of the seismic isolation damper D is Is as indicated by the line L1 in FIG.

  Further, when the seismic isolation damper D exhibits a contraction operation and the piston 2 moves from the neutral position to the cylinder 1 with a predetermined range exceeding the predetermined range, the pressure side bypass passage is formed when the piston 2 exceeds the predetermined range. 9 and the discharge side bypass passage 10 are switched from a state in which they effectively function to an invalid state. When the moving speed of the piston 2 during the contraction operation of the seismic isolation damper D is lower than a predetermined speed, the second pressure-side damping valve 16 and the second base valve are moved when the piston 2 exceeds a predetermined range toward the pressure-side chamber R2. As a result, the damping force of the seismic isolation damper D changes from the line L4 in FIG. 4 to the line L3 as indicated by the broken line arrow. On the other hand, when the moving speed of the piston 2 during the contraction operation of the seismic isolation damper D is equal to or higher than a predetermined speed, the pressure-side speed-dependent opening / closing valve 19 and the discharge-side speed-dependent opening / closing valve 20 are closed. The damping force of the seismic damper D is as shown by the middle line L3 in FIG.

  Thus, the seismic isolation damper D of the present invention includes the cylinder 1, the piston 2 that is slidably inserted into the cylinder 1 and divides the cylinder 1 into the expansion side chamber R1 and the compression side chamber R2, and the cylinder 1 A rod 3 that is inserted and connected at one end to the piston 2, a tank T that stores hydraulic oil (liquid), an extension side damping passage 4 and a pressure side damping passage 5 that communicate the extension side chamber R1 and the pressure side chamber R2. The discharge passage 6 and the suction passage 7 communicating the pressure side chamber R2 and the tank T, and the extension side attenuation passage 4 are provided in the extension side damping passage 4 and allow only the flow of hydraulic oil (liquid) from the extension side chamber R1 toward the pressure side chamber R2. The first extension side damping valve 11 that provides resistance to the flow of the working oil (liquid) that passes through, and the flow of the working oil (liquid) that is provided in the compression side damping passage 5 and that travels from the compression side chamber R2 to the extension side chamber R1 are allowed. Actuating with The first pressure side damping valve 12 that provides resistance to the flow of (liquid) and the hydraulic oil (liquid) that is provided in the discharge passage 6 and allows only the flow of hydraulic oil (liquid) from the pressure side chamber R2 to the tank T and passes therethrough. ), A check valve 14 that is provided in the suction passage 7 and allows only the flow of hydraulic oil (liquid) from the tank T toward the pressure side chamber R2, and the center side of the cylinder 1 Only when the piston 2 is positioned within a predetermined range set to the expansion side bypass path 8 and the pressure side bypass path 9 that communicate the expansion side chamber R1 and the pressure side chamber R2, and the piston 2 includes the predetermined range with respect to the cylinder 1 The discharge-side bypass passage 10 that connects the pressure-side chamber R2 and the tank T only when it is on the extension-side chamber R1 side, and the hydraulic oil that is provided in the extension-side bypass passage 8 and heads from the extension-side chamber R1 to the pressure-side chamber R2. A second expansion side damping valve 15 that allows only the flow of the liquid) and provides resistance to the flow of the hydraulic fluid (liquid) that passes therethrough, and the expansion side bypass path 8 is provided on the expansion side chamber R1. When communicating with the pressure side chamber R2, when the moving speed of the piston 2 toward the extension side chamber R1 with respect to the cylinder 1 exceeds a predetermined speed, an extension side speed-dependent opening / closing valve 18 that shuts off the extension side bypass passage 8, and a pressure side bypass A second pressure-side damping valve 16 provided in the passage 9 for allowing only the flow of hydraulic fluid (liquid) from the pressure-side chamber R2 toward the expansion-side chamber R1 and for providing resistance to the flow of hydraulic fluid (liquid) passing therethrough; In the case where the pressure side bypass passage 9 is provided in the passage 9 and connects the pressure side chamber R2 and the extension side chamber R1, if the moving speed of the piston 2 toward the pressure side chamber R2 with respect to the cylinder 1 exceeds a predetermined speed, the pressure is increased. The pressure side speed-dependent opening / closing valve 19 that shuts off the side bypass path 9 and the hydraulic oil (liquid) that is provided in the discharge side bypass path 10 and allows only the flow of hydraulic oil (liquid) from the pressure side chamber R2 to the tank T and passes therethrough. ) In the discharge side bypass passage 10 and the discharge side bypass passage 10 communicates with the pressure side chamber R2 and the tank T, the pressure side of the piston 2 with respect to the cylinder 1 When the moving speed to the chamber R2 side becomes equal to or higher than a predetermined speed, a discharge-side speed-dependent opening / closing valve 20 that shuts off the discharge-side bypass path 10 and the discharge-side bypass path 10 are provided in the pressure-side chamber R2 and the tank. A discharge-side opening / closing valve that opens the discharge-side bypass passage 10 only when the piston 2 moves toward the pressure-side chamber R2 with respect to the cylinder 1 when communicating with T. It is equipped with a 1 and.

  In the seismic isolation damper D configured as described above, when each of the bypass passages 4, 5, and 10 is activated, the second expansion side damping valve 15 is replaced with the first compression side damping valve with respect to the first expansion side damping valve 11. 12, the second pressure side damping valve 16 functions effectively, and the second base valve 17 functions effectively with respect to the first base valve 13. Therefore, even when the seismic isolation damper D is contracted, if the piston 2 is located within a predetermined range with respect to the cylinder 1 and the moving speed of the piston 2 is lower than the predetermined speed, only the first base valve 13 is used. Since the hydraulic oil (liquid) can be discharged from the cylinder 1 to the tank T through the second base valve 17, the damping force during the contraction operation can be reduced as compared with the conventional seismic isolation damper. Therefore, according to the seismic isolation damper D of the present invention, it is possible to easily match the damping force characteristics between the extension operation and the contraction operation even when the damping force depending on the displacement can be exhibited.

  Furthermore, the seismic isolation damper D of the present invention not only depends on the displacement and increases or decreases the damping force, but also when the moving speed of the piston 2 relative to the cylinder 1 becomes high, the piston 2 is positioned within a predetermined range with respect to the cylinder 1. Even if it is done, the damping force can be increased. Therefore, even if the seismic isolation damper D is used in combination with the seismic isolation device M, the damping force is reduced for small-scale earthquakes so that the seismic isolation effect of the seismic isolation device M is not impaired. Can be ensured, and for large earthquakes, a high damping force can be exerted to prevent the structure from falling off the seismic isolation bearing M and the collision between the structure S and the retaining wall surrounding the lower end of the structure. .

  In the seismic isolation damper D of the present invention, the bypass passages 4, 5, 10 and all the valves 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 are provided in the outer cylinder 24. Since it is accommodated, when it is installed between the structure S and the ground G, there is no worry of interference with other parts, and conveyance becomes easy.

  In the above description, the first expansion side damping valve 11, the second expansion side damping valve 15, the first pressure side damping valve 12, the second pressure side damping valve 16, the first base valve 13 and the second base valve 17 are: Although both are pressure regulating valves, the present invention is not limited to this, and any valve that can exhibit a damping force may be used.

  Although the preferred embodiments of the present invention have been described in detail above, modifications, changes and modifications can be made without departing from the scope of the claims.

DESCRIPTION OF SYMBOLS 1 ... Cylinder, 2 ... Piston, 3 ... Rod, 4 ... Extension side damping channel, 5 ... Pressure side damping channel, 6 ... Discharge channel, 7 ... Suction channel, 8・ ・ ・ Extension side bypass passage, 9 ... Pressure side bypass passage, 10 ... Discharge side bypass passage, 11 ... First extension side damping valve, 12 ... First pressure side damping valve, 13 ... 1st base valve, 14 ... check valve, 15 ... second extension side damping valve, 16 ... second pressure side damping valve, 17 ... second base valve, 18 ... dependent on extension side speed Open / close valve, 19 ... pressure side speed dependent open / close valve, 20 ... discharge side speed dependent open / close valve, 21 ... discharge side open / close valve, D ... seismic isolation damper, R1 ... extension side chamber, R2 ... Pressure side chamber, T ... Tank

Claims (1)

A cylinder,
A piston that is slidably inserted into the cylinder and divides the cylinder into an extension side chamber and a pressure side chamber;
A rod inserted into the cylinder and connected at one end to the piston;
A tank for storing liquid;
An extension side attenuation passage and a pressure side attenuation passage communicating the extension side chamber and the pressure side chamber;
A discharge passage and a suction passage communicating the pressure side chamber and the tank;
A first extension side damping valve that is provided in the extension side damping passage and that allows only the flow of liquid from the extension side chamber to the compression side chamber and that provides resistance to the flow of liquid passing therethrough;
A first pressure-side damping valve that is provided in the pressure-side damping passage and allows only the flow of liquid from the pressure-side chamber toward the extension-side chamber and gives resistance to the flow of liquid passing therethrough;
A first base valve that is provided in the discharge passage and allows only the flow of liquid from the pressure side chamber toward the tank and provides resistance to the flow of liquid passing therethrough;
A check valve that is provided in the suction passage and allows only a flow of liquid from the tank toward the pressure side chamber;
An extension side bypass passage and a pressure side bypass passage communicating the extension side chamber and the pressure side chamber only when the piston is located within a predetermined range set on the center side of the cylinder;
A discharge-side bypass passage that communicates the pressure-side chamber and the tank only when the piston is on the extension-side chamber side including the predetermined range with respect to the cylinder;
A second extension side damping valve that is provided in the extension side bypass passage and allows only the flow of liquid from the extension side chamber to the pressure side chamber and provides resistance to the flow of liquid passing therethrough;
When the extension side bypass passage is provided in the extension side bypass passage and communicates the extension side chamber and the pressure side chamber, the moving speed of the piston toward the extension side chamber with respect to the cylinder is equal to or higher than a predetermined speed. Then, the extension side speed-dependent on-off valve that shuts off the extension side bypass path,
A second pressure-side damping valve that is provided in the pressure-side bypass and that allows only the flow of liquid from the pressure-side chamber to the extension-side chamber and provides resistance to the flow of liquid that passes through;
When the pressure side bypass passage is provided in the pressure side bypass passage and the pressure side bypass passage communicates with the pressure side chamber and the extension side chamber, the moving speed of the piston toward the pressure side chamber with respect to the cylinder is equal to or higher than a predetermined speed. A pressure-side speed-dependent on-off valve that shuts off the pressure-side bypass path;
A second base valve that is provided in the discharge-side bypass and allows only the flow of liquid from the pressure-side chamber to the tank and provides resistance to the flow of liquid that passes through;
When the discharge side bypass passage communicates with the pressure side chamber and the tank, the moving speed of the piston toward the pressure side chamber with respect to the cylinder is equal to or higher than a predetermined speed. A discharge-side speed-dependent on-off valve that shuts off the discharge-side bypass path,
The discharge side bypass path is provided in the discharge side bypass path, and the discharge side bypass path communicates the pressure side chamber and the tank only when the piston moves to the pressure side chamber side with respect to the cylinder. A seismic isolation damper comprising a discharge-side opening / closing valve that opens the bypass.

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