JP7186388B2 - seismic isolation damper - Google Patents

Description

The present invention relates to a seismic isolation damper.

A seismic isolation system is equipped with seismic isolation systems such as ball bearings, sliding bearings, and laminated rubber that are interposed between the ground and the structure. transmission to the structure. In addition to the above-described seismic isolation bearings, the seismic isolation device is equipped with a hydraulic damper interposed between the ground and the structure. The vibration of the structure is suppressed by damping it with

In the Kumamoto earthquake that occurred in 2016, strong long-period seismic motion was observed in the vicinity of the epicenter. On the other hand, there is a limit to the stroke length of the hydraulic damper, and when the structure is greatly displaced by the input of long-period seismic motion, the seismic isolation damper expands or contracts the most, reducing the seismic motion isolation effect of the seismic isolation bearing system. vibration is transmitted to the structure.

In addition, if the damping force of the hydraulic damper becomes excessively large for a large shake in which the expansion and contraction speed of the hydraulic damper reaches a high speed range, the hydraulic damper itself may be damaged.

In order to deal with this problem, even if we try to increase the strength of the hydraulic damper and increase the stroke length, the increased length of the hydraulic damper causes problems such as buckling, increased size, and increased weight. Due to the difficulty, a hydraulic damper with a stroke length and strength that can withstand long-period seismic motion is not realistic.

Therefore, in order to secure the stroke length of the hydraulic damper and prevent damage, there have been proposed vibration dampers and seismic isolation dampers in which a hydraulic damper and a friction damper are connected in series. Specifically, the vibration control damper is configured by connecting a hydraulic damper and a friction damper in series, and is interposed between the beams of the structure (see, for example, Patent Document 1). Also, the seismic isolation damper has a hydraulic damper and a friction damper connected in series. A disk spring is interposed between the sliding surface and the carriage and presses the sliding surface toward the friction surface (see Patent Document 2, for example).

Japanese Patent Application Laid-Open No. 09-268802 Japanese Unexamined Patent Application Publication No. 2011-94708

The damper for damping disclosed in Japanese Patent Application Laid-Open No. 09-268802 has a structure in which a hydraulic damper and a friction damper are simply connected in series and is very long. When interposed between an object and the ground, there is a risk of buckling if a large axial force acts in the axial direction. Also, the input of seismic motion causes the hydraulic damper and the friction damper to rotate in the horizontal direction. There is also the problem of storage.

In addition, the seismic isolation damper disclosed in Japanese Patent Application Laid-Open No. 2011-94708 employs a structure in which the friction damper is sandwiched between the structure and the ground. If the vertical distance fluctuates greatly, the load of the disk spring that presses the sliding surface against the friction surface will fluctuate. Therefore, the friction damper in this seismic isolation damper varies in the load at which it begins to expand and contract depending on the input state of seismic motion, so there is a possibility that the seismic isolation damper cannot exhibit the desired damping force. Furthermore, since the direction of displacement of the friction damper is not constrained, there is also the problem that the hydraulic damper can move freely in the horizontal direction, and the displacement remains even after the seismic motion ends, causing the hydraulic damper to become oblique with respect to its original installation posture. be.

Therefore, the present invention can prevent buckling while ensuring a stroke length that can withstand long-period seismic motion, and generate a stable damping force while preventing damage to the seismic isolation damper and its peripheral members. To provide a seismic isolation damper capable of suppressing residual displacement in a seismic isolation layer after the end of an earthquake.

In order to achieve the above object, the seismic isolation damper of the present invention comprises a hydraulic damper, a structure-side mounting device for mounting the hydraulic damper to a structure so as to be horizontally rotatable, and a hydraulic damper horizontally rotatably mounted on the ground. The structure side mounting device and the ground side mounting device are composed of a resistance member that exerts a resistance force that prevents expansion and contraction by constraining the expansion and contraction direction in one direction, and one end of the resistance member that is hydraulically connected. and a damper-side bracket connected to the damper, the resistance member is a friction damper or a steel damper, and expands and contracts only when the damping force generated by the hydraulic damper exceeds a predetermined load, and the structure-side mounting device includes: It has a resistance member, a damper-side bracket that connects one end of the resistance member to the hydraulic damper, and a structure-side locking device that switches whether the resistance member can be expanded or contracted. It has a damper-side bracket that connects one end to a hydraulic damper, and a ground-side locking device that switches whether the resistance member can be extended or retracted. is different from the value of the specified load .

According to the seismic isolation damper configured in this way, the hydraulic damper and the resistance member are arranged in series, so the stroke length can be secured, and the resistance member can be attached to one or both of the structure-side mounting device and the ground-side mounting device. As it is built in, it prevents buckling of the hydraulic damper and the resistance member. In addition, since the resistance member is incorporated in the structure-side mounting device or the ground-side mounting device, a constant resistance force can be exerted even if the vertical distance between the structure and the ground changes. Furthermore, according to the seismic isolation damper configured in this way, the characteristic of the damping force can be changed according to the seismic motion, and the vibration of the structure can be effectively suppressed.

In addition, one or both of the structure-side mounting device and the ground-side mounting device in the seismic isolation damper includes a fixed-side bracket for mounting the resistance member to the structure or the ground, and a damper-side bracket that connects the structure or the ground to the A guide member may be provided for guiding movement of the damper-side bracket as the member expands and contracts. According to the seismic isolation damper configured in this manner, the damper-side bracket guides the movement of the resistance member in the extension/contraction direction with respect to the structure or the ground. It becomes difficult to input a moment, so that buckling can be effectively prevented, and since the guide member can constrain the resistance member in the expansion and contraction direction, the degree of freedom in designing the resistance member is improved.

A vibration isolation damper according to another invention includes a hydraulic damper, a structure-side mounting device for horizontally rotatably mounting the hydraulic damper to the structure, and a ground-side mounting device for horizontally rotatably mounting the hydraulic damper to the ground. One or both of the structure side mounting device and the ground side mounting device includes a resistance member that exerts a resistance force that prevents expansion and contraction by restraining the expansion and contraction direction in one direction, and one end of the resistance member is connected to the hydraulic damper. The hydraulic damper has a connecting damper side bracket, and the hydraulic damper divides the expansion and contraction speed into a low speed lower than the first speed, a medium speed higher than the first speed and lower than the second speed, and a high speed higher than the second speed . The damping coefficient changes with the switching of the compression speed category , and has damping force characteristics where the damping coefficient is maximized when the expansion and contraction speed is in the middle speed range , and the resistance member is a friction damper or a steel damper. The hydraulic damper expands and contracts only when the damping force generated by the hydraulic damper exceeds a predetermined load, and the predetermined load is set to a load higher than the damping force exerted by the hydraulic damper when the expansion and contraction speed becomes the second speed. According to the seismic isolation damper configured in this way, the seismic isolation effect is not impaired against small and medium-sized seismic motions with relatively small shaking, and high damping force is generated against large-amplitude seismic motions. , can effectively suppress vibration.

Furthermore , according to the seismic isolation damper configured in this way, the amount of vibration energy to be absorbed increases, and the damping effect of the structure can be improved.

Therefore, according to the seismic isolation damper of the present invention, it is possible to prevent buckling while ensuring a stroke length capable of coping with long-period seismic motion, and to prevent damage to the seismic isolation damper and the peripheral members of the seismic isolation damper. It is possible to generate a stable damping force while suppressing the residual displacement in the seismic isolation layer after the end of the earthquake.

FIG. 2 is a side view of a state in which a seismic isolation damper and a seismic isolation bearing device according to the embodiment are interposed between a structure and the ground; FIG. 4 is a damping force characteristic diagram of a hydraulic damper of a seismic isolation damper in one embodiment; 1 is a schematic cross-sectional view of a hydraulic damper of a seismic isolation damper in one embodiment; FIG. FIG. 4 is a pressure flow rate characteristic diagram of a pressure regulating valve of the hydraulic damper of the seismic isolation damper according to the embodiment; FIG. 4 is a cross-sectional view of an example of a pressure regulating valve of a hydraulic damper of a seismic isolation damper according to one embodiment; FIG. 4 is a pressure flow rate characteristic diagram of a damping portion of a hydraulic damper of a seismic isolation damper according to one embodiment; FIG. 3 is a damping force characteristic diagram of a friction damper of a seismic isolation damper in one embodiment; FIG. 5 is a diagram showing characteristics of damping force with respect to displacement of the hydraulic damper of the seismic isolation damper in one embodiment. FIG. 5 is a graph showing characteristics of damping force with respect to displacement of a friction damper of a seismic isolation damper in one embodiment; FIG. 4 is a diagram showing characteristics of damping force with respect to displacement of a seismic isolation damper in one embodiment; FIG. 11 is a side view of a seismic isolation damper in a first modified example of one embodiment; FIG. 11 is a side view of a seismic isolation damper in a second modified example of one embodiment; It is a side view of the damper for seismic isolation in the 3rd modification of one embodiment. It is a front view of the ground side mounting device of the damper for seismic isolation in the 3rd modification of one embodiment.

The present invention will be described below based on the illustrated embodiments. The seismic isolation damper D1 in one embodiment, as shown in FIG. It is equipped with a ground-side mounting device GB that is horizontally rotatable and attached to the ground G, and is interposed between the structure S and the ground G together with a seismic isolation bearing device M made of laminated rubber for seismic isolation. Works as part of the device. In addition, although the seismic isolation bearing device M is made of laminated rubber as shown in the figure, it may be one that slides or rolls the structure S. As shown in FIG.

Each part of the seismic isolation damper D1 will be described in detail below. First, the hydraulic damper OD expands and contracts when the structure S and the ground G are relatively displaced, and exerts a damping force that suppresses the vibration of the structure S. Then, the expansion and contraction speed is divided into a first speed Va and a second speed Vb higher than the first speed Va, a low speed lower than the first speed Va, a medium speed higher than the first speed Va and lower than the second speed Vb, and The speed is higher than the second speed Vb. As shown in FIG. 2, the damping force characteristic, which is the characteristic of the damping force exerted with respect to the expansion/contraction speed of the hydraulic damper OD, changes the damping coefficient according to the switching of the expansion/contraction speed category. , the damping coefficient is set to be maximum when the expansion and contraction speed is in the middle speed range. More specifically, the damping force characteristic of the hydraulic damper OD of the present embodiment has a low damping coefficient when the expansion/contraction speed is in the low speed range, and a high damping coefficient when the expansion/contraction speed is in the medium speed range. The damping coefficient is set to decrease again when the speed is in the high speed range. Therefore, the damping force characteristic of the hydraulic damper OD of the present embodiment has a switching point Pa and a switching point Pb at which the damping force is switched between the first speed Va and the second speed Vb, respectively, and the expansion/contraction speed changes from low speed to high speed. , the damping coefficient changes in the order of low, high, and low.

Since the hydraulic damper OD with the damping force characteristics set in this way exerts a low damping force when the expansion/contraction speed is low, the vibration isolation of the structure S by the seismic isolation bearing device M is not hindered. However, when a large vibration with a high expansion/contraction speed acts on the structure S, a high damping force is exerted, so that the vibration of the structure S can be suppressed with a high damping force. Therefore, if this hydraulic damper OD is used, it does not impair the seismic isolation effect against small and medium-sized seismic motions with relatively small tremors, and generates a high damping force against large-amplitude seismic motions, effectively Vibration can be suppressed. In addition, since the hydraulic damper OD exerts a high damping force against large-amplitude seismic motion, it is possible to prevent excessive displacement of the structure.

In addition, when the expansion and contraction speed reaches the medium speed range, the hydraulic damper OD exhibits damping force characteristics in which the damping coefficient is increased and the damping force changes from low damping force to high damping force. In contrast, the structure S does not need to be subjected to sudden changes in acceleration, so that the structure S can be protected and the people and equipment in the structure S can be prevented from being overloaded.

As an example for realizing such damping force characteristics of the hydraulic damper OD, for example, the structure of the hydraulic damper OD may be configured as follows. Hydraulic damper OD, as shown in FIG. A rod 3 that is movably inserted and connected to the piston 2; and damping portions V1, V2, V3 provided in the expansion side passage 4, the compression side passage 5, and the discharge passage 6, respectively.

The inside of the cylinder 1 is partitioned by the piston 2 into an expansion side chamber R1 and a compression side chamber R2. An outer cylinder 7 covering the cylinder 1 is provided on the outer peripheral side of the cylinder 1, and an annular gap between the cylinder 1 and the outer cylinder 7 forms a reservoir R. The left end of the outer cylinder 7 in FIG. 3 is closed by an annular rod guide 8 which guides the movement of the rod 3 in the axial direction through which the rod 3 is inserted. The rod 3 is inserted into the cylinder 1 and has one end connected to the piston 2 and the other end protruding outside the cylinder 1 . The rod 3, as shown in FIG. 1, has an eye-shaped bracket 3a that enables connection to the structure-side mounting device SB or the ground-side mounting device GB.

The right end of the cylinder 1 in FIG. 3 is closed by a bottom member 9, and the right end of the outer cylinder 7 in FIG. The cylinder 1 , together with the bottom member 9 , is housed and fixed in the outer cylinder 7 while being sandwiched between the rod guides 8 fixed to both ends of the outer cylinder 7 and the lid 10 . The lid 10, as shown in FIG. 1, has an eye-shaped bracket 10a that enables connection to the structure-side mounting device SB or the ground-side mounting device GB.

In this case, the expansion side chamber R1 and the compression side chamber R2 are filled with hydraulic oil, and the reservoir R is also filled with hydraulic oil. In this example, hydraulic oil is used as the working medium for the hydraulic damper OD, but liquids other than hydraulic oil may be used, such as water and aqueous solutions.

The piston 2 is provided with an expansion-side passage 4 and a compression-side passage 5 that communicate the expansion-side chamber R1 and the compression-side chamber R2. The expansion side passage 4 is provided with an attenuation portion V1, and the compression side passage 5 is provided with an attenuation portion V2. The damping portion V1 includes a pressure regulating valve PV and a relief valve RV arranged in parallel with the pressure regulating valve PV, and allows only the flow of hydraulic oil passing through the growth side passage 4 from the growth side chamber R1 to the compression side chamber R2. Resistance is given to the flow, and the expansion side passage 4 is set as a one-way passage. Like the damping section V1, the damping section V2 includes a pressure regulating valve PV and a relief valve RV parallel to the pressure regulating valve PV. This flow is resisted while allowing the pressure side passage 5 to be set as a one-way passage. In this example, the expansion side passage 4 and the compression side passage 5 are both provided in the piston 2, but the installation location is not limited to the piston 2. For example, the expansion side chamber R1 and the compression side chamber R2 are provided outside the cylinder 1. may be configured to communicate with each other.

The bottom member 9 is provided with a discharge passage 6 and a suction passage 11 that communicate the pressure-side chamber R2 and the reservoir R with each other. The discharge passage 6 is provided with an attenuation section V3. Like the damping units V1 and V2, the damping unit V3 includes a pressure regulating valve PV and a relief valve RV arranged in parallel with the pressure regulating valve PV. The discharge passage 6 is set as a one-way passage by giving resistance to this flow while allowing only the flow. The suction passage 11 is provided with a check valve 12 that allows only the flow of hydraulic fluid from the reservoir R to the compression side chamber R2. It is set as a one-way passage that only allows the flow of oil. Note that the discharge passage 6 and the suction passage 11 are both provided in the bottom member 9 in this example, but the installation location is not limited to the bottom member 9 .

When the hydraulic damper OD configured as described above is extended, the expansion side chamber R1 is compressed and the compression side chamber R2 is expanded by the movement of the piston 2 to the left in FIG. 4 from the growth side chamber R1 to the compression side chamber R2. Further, when the hydraulic damper OD is extended, the rod 3 is withdrawn from the cylinder 1, so that the volume of the hydraulic oil withdrawn from the cylinder 1 of the rod 3 is supplied from the reservoir R into the cylinder 1 via the suction passage 11. Since the damping portion V1 provides resistance to the flow of hydraulic fluid from the expansion side chamber R1 to the compression side chamber R2, the pressure in the expansion side chamber R1 rises and a pressure difference occurs between the expansion side chamber R1 and the compression side chamber R2. , thereby, the hydraulic damper OD exerts an extension-side damping force that suppresses extension.

When the hydraulic damper OD contracts, the compression side chamber R2 is compressed by the movement of the piston 2 to the right in FIG. It moves from R2 to expansion side room R1. Further, when the hydraulic damper OD is contracted, the rod 3 enters the cylinder 1, so that the hydraulic oil corresponding to the volume of the rod 3 entering the cylinder 1 is discharged from the cylinder 1 to the reservoir R through the discharge passage 6. be. The damping portion V2 and the damping portion V3 provide resistance to the flow of hydraulic fluid from the compression-side chamber R2 to the expansion-side chamber R1, and to the flow of hydraulic fluid from the compression-side chamber R2 to the reservoir R, respectively. As a result, the pressure in the compression-side chamber R2 rises to create a pressure difference between the compression-side chamber R2 and the expansion-side chamber R1, and the hydraulic damper OD exerts a compression-side damping force that suppresses contraction.

Next, attenuation units V1, V2, and V3 will be described. The damping units V1, V2, and V3 each include a pressure regulating valve PV having the same configuration and a relief valve RV arranged in parallel with the pressure regulating valve PV. The pressure regulating valve PV is energized by a spring and set to a normally closed type, and changes the degree of valve opening according to the upstream pressure to provide resistance to the flow of hydraulic oil. Here, the flow rate passing through the attenuation portions V1, V2, V3 is proportional to the expansion/contraction speed when the hydraulic damper OD expands and contracts. Therefore, when the expansion/contraction speed of the hydraulic damper OD is in the low speed range, the flow rate passing through the damping units V1, V2, and V3 is small, and when the expansion/contraction speed is in the high speed range, the flow rate is large and the expansion/contraction speed is low. In the medium speed range, which is intermediate between the high speed range and the high speed range, the flow rate is moderate. As shown in FIG. 4, the pressure flow rate characteristic of the single pressure regulating valve PV is such that when the expansion/contraction speed of the hydraulic damper OD is in the low speed range, the rate of increase in pressure is small with respect to the increase in expansion/contraction speed. show. On the other hand, the pressure flow rate characteristic of the single pressure regulating valve PV shows that when the expansion/contraction speed reaches a middle speed range between the low speed region and the high speed region, the pressure increases greatly with the increase in the expansion/contraction speed.

The pressure regulating valve PV can be realized by adopting the structure disclosed in Japanese Patent No. 5508883, for example. Specifically, as shown in FIG. 5, the pressure regulating valve PV includes a valve seat 100 provided in the middle of the passage, a valve element 101 movably accommodated in the passage and seated on and off the valve seat 100, and a valve body 101. A spring 102 biases the valve body 101 toward the valve seat 100, and when the amount of retraction of the valve body 101 from the valve seat 100 reaches a predetermined amount, the valve body 101 collides with the valve body 101 to move the valve body 101 away from the valve seat 100. A stopper 103 for restricting the above backward movement may be provided. In the pressure regulating valve PV constructed in this way, when the expansion/contraction speed is low, the spring 102 is compressed by the upstream pressure, and the valve element 101 is separated from the valve seat 100 to open the valve. As a result, the amount of retraction of the valve body 101 from the valve seat 100 increases. In this way, when the expansion/contraction speed is in the low speed range, the degree of valve opening increases as the expansion/contraction speed increases, so the pressure flow characteristics of the pressure regulating valve PV exhibit a characteristic with a small slope as shown in FIG. On the other hand, when the expansion/contraction speed increases and reaches the middle speed range, the amount of retraction of the valve body 101 increases, and when the expansion/contraction speed reaches the middle speed range, the valve body 101 abuts against the stopper 103, causing the valve body 101 to move. Retraction from the above valve seat 100 is regulated. In this way, when the expansion/contraction speed is in the middle speed range, the valve opening degree remains constant even if the expansion/contraction speed increases. exhibit great properties. Therefore, when the expansion/contraction speed increases from the low speed range to the medium speed range, the pressure regulating valve PV exhibits a characteristic that the slope increases and the pressure rise increases. The pressure flow characteristic of the pressure regulating valve PV when the expansion and contraction speed is in the medium speed range may be an orifice characteristic proportional to the square of the flow rate or a port characteristic proportional to the flow rate.

In addition to restricting the amount of retraction of the valve body 101 by the stopper 103, a structure in which an orifice is provided downstream of the valve body 101 can also be adopted. In such a pressure regulating valve PV, when the flow passage area between the valve seat 100 and the valve body 101 reaches or exceeds a predetermined value, the orifice operates more than the resistance exerted by the valve seat 100 and the valve body 101 on the flow of hydraulic oil. It should be set so that the resistance to the oil flow is greater. The predetermined value can be set according to the flow area of the orifice. In the pressure regulating valve PV configured in this manner, the spring 102 is compressed by the upstream pressure and the valve body 101 is moved from the valve seat 100 when the expansion and contraction speed is low. The valve is released to open the valve, and the retraction amount of the valve body 101 from the valve seat 100 increases as the expansion and contraction speed increases. In this way, when the expansion/contraction speed is in the low speed range, the degree of valve opening increases as the expansion/contraction speed increases. It shows the property of small increase. On the other hand, when the expansion and contraction speed increases and reaches the middle speed range, the retraction amount of the valve body 101 increases, the flow passage area exceeds a predetermined value, and the characteristics of the orifice appear. Since it is constant, the pressure regulating valve PV exhibits the characteristic that the pressure increases with increasing expansion/contraction speed.

On the other hand, the relief valve RV opens when the differential pressure across it reaches a predetermined valve opening pressure, but the valve opening pressure is set so that it does not open until the expansion/contraction speed reaches a high speed range. The pressure flow characteristic after the relief valve RV is opened is such that the rate of increase in pressure is small with respect to the increase in expansion/contraction speed. Therefore, the damping units V1, V2, V3, which are a combination of the pressure regulating valve PV and the relief valve RV, have pressure flow rate characteristics shown in FIG. Specifically, the damping units V1, V2, and V3 exhibit the characteristics of the pressure regulating valve PV when the expansion/contraction speed is in the low and medium speed ranges, and the relief valve RV opens when the expansion/contraction speed reaches the high speed range. The characteristics of the relief valve RV are shown.

The hydraulic damper OD is configured as described above. As described above, when the hydraulic damper OD expands, the hydraulic oil moves from the expansion side chamber R1 to the compression side chamber R2 through the expansion side passage 4, A volume of the hydraulic oil withdrawn from the cylinder 1 is supplied from the reservoir R into the cylinder 1 through the suction passage 11 . The damping portion V1 provides resistance to the flow of hydraulic fluid from the expansion-side chamber R1 to the compression-side chamber R2, so that the hydraulic damper OD exerts an expansion-side damping force that suppresses expansion. Here, the pressure flow characteristics of the damping section V1 are as shown in FIG. When the hydraulic damper OD expands, the flow rate passing through the damping section V1 is proportional to the expansion/contraction speed, which is the expansion speed. Therefore, the damping force characteristic exerted by the hydraulic damper OD is similar to the pressure flow rate characteristic of the damping section V1, as shown in FIG. Therefore, the hydraulic damper OD exerts a low damping force with a small damping coefficient in the low expansion/contraction speed range and a small increase rate of the damping force with respect to an increase in the expansion/contraction speed. In addition, the hydraulic damper OD exhibits a damping force characteristic in which the damping coefficient increases as the telescoping speed increases from the low speed range to the middle speed range, and the rate of increase in the damping force is large with respect to the increase in the telescoping speed. Furthermore, in the hydraulic damper OD, when the telescopic speed increases from the medium speed range to the high speed range, the relief valve RV opens, so the damping coefficient is switched and becomes smaller, and the rate of increase in the damping force becomes small with respect to the increase in the telescopic speed. It exhibits high damping force. When the expansion/contraction speed is in the middle speed range, the hydraulic damper OD exerts a damping force that changes from the low damping force to the high damping force as the expansion/contraction speed increases. In FIG. 2, the first speed Va at the boundary between the low speed range and the medium speed range is 60 cm/s, and the second speed Vb at the boundary between the medium speed range and the high speed range is 90 cm/s. This is just an example, and may be set to an optimum value depending on the specifications of the structure, etc., as will be described later.

On the other hand, when the hydraulic damper OD contracts, the hydraulic fluid moves from the compression side chamber R2 to the expansion side chamber R1 through the compression side passage 5, and the volume of the hydraulic oil entering the cylinder 1 of the rod 3 flows through the discharge passage 6. It is discharged from inside the cylinder 1 into the reservoir R. The damping portion V2 and the damping portion V3 provide resistance to the flow of hydraulic fluid from the compression-side chamber R2 to the expansion-side chamber R1, and to the flow of hydraulic fluid from the compression-side chamber R2 to the reservoir R, respectively. Here, the pressure flow rate characteristics of the damping portions V2 and V3 are also as shown in FIG. 6, like the damping portion V1. Therefore, as shown in FIG. 2, the hydraulic damper OD exerts a low damping force in which the damping coefficient is small in the low expansion/retraction speed range and the rate of increase in the damping force is small with respect to the increase in the expansion/retraction speed. In addition, the hydraulic damper OD exhibits a damping force characteristic in which the damping coefficient increases as the telescoping speed increases from the low speed range to the middle speed range, and the rate of increase in the damping force is large with respect to the increase in the telescoping speed. Furthermore, in the hydraulic damper OD, when the telescopic speed increases from the medium speed range to the high speed range, the relief valve RV opens, so the damping coefficient is switched and becomes smaller, and the rate of increase in the damping force becomes small with respect to the increase in the telescopic speed. It exhibits high damping force. When the expansion/contraction speed is in the middle speed range, the hydraulic damper OD exerts a damping force that changes from the low damping force to the high damping force as the expansion/contraction speed increases.

The specific configuration of the hydraulic damper OD described above is an example of a configuration for realizing the damping force characteristics shown in FIG. A damper OD may be configured.

Subsequently, the structure-side mounting device SB includes a reaction wall 15 attached to the structure S to receive the load of the seismic isolation damper D1, and a hydraulic damper attached to the reaction wall 15 via the reaction wall 15. a bracket 16 connecting the OD to the structure S; The bracket 16 has a shaft 16a inserted into the eye-shaped bracket 10a of the hydraulic damper OD, and the hydraulic damper OD is allowed to rotate in the horizontal direction around the shaft 16a. Therefore, the hydraulic damper OD is connected to the structure S by the structure-side mounting device SB while being allowed to rotate in the horizontal direction with respect to the structure S.

The ground-side mounting device GB includes a fixed-side bracket 17 attached to the ground G to receive the load of the seismic isolation damper D1, a damper-side bracket 18 connected to the hydraulic damper OD, and a friction damper FD as a resistance member. I have. The stationary bracket 17 includes a base 17a fixed to the ground G and a reaction wall 17b attached to the base 17a. The damper-side bracket 18 has a shaft 18a inserted into the eye-shaped bracket 3a of the hydraulic damper OD, and the hydraulic damper OD is allowed to rotate in the horizontal direction around the shaft 18a.

The damper-side bracket 18 is attached to the base 17a of the fixed-side bracket 17 by a linear guide 19 as a guide member. The linear guide 19 is provided with a guide rail 19a attached to the base 17a along the horizontal direction in FIG. 1, and a slider 19b running on the guide rail 19a. The damper-side bracket 18 is attached to the slider 19b and can reciprocate along the guide rail 19a. Therefore, the movement of the damper-side bracket 18 is guided by the linear guide 19 as a guide member, and it can move in the lateral direction in FIG. Since the guide member only needs to guide the movement of the damper-side bracket 18 with respect to the ground G, a device other than the linear guide 19, such as a guide device consisting of a rod and a slider that slides on the outer circumference of the rod, may be used. good.

In addition, the friction damper FD includes a first rod 20, a second rod 21 that is relatively movable with respect to the first rod 20, and a base end of the first rod 20 that is attached to a surface facing the second rod 21. and a friction plate 23 attached to the proximal end of the second rod 21 and in contact with the friction plate 22 .

The tip of the first rod 20, which is one end of the friction damper FD, is fixedly attached to the damper-side bracket 18, and the tip of the second rod 21, which is the other end of the friction damper FD, is attached to the fixed-side bracket 17. is fixedly attached to the reaction wall 17b. The moving direction of the damper-side bracket 18 is constrained in the left-right direction in FIG. 1 by the linear guide 19 as a guide member. Movement is limited to left and right only. In this way, the friction damper FD is constrained to expand and contract in one direction, and is allowed to expand and contract only in the horizontal direction in FIG. In the present embodiment, the expansion/contraction direction of the friction damper FD as a resistance member is the same as the expansion/contraction direction of the hydraulic damper OD in the initial state where the seismic isolation damper D1 is attached between the structure S and the ground G. is set to be In this way, the expansion and contraction directions of the hydraulic damper OD and the friction damper FD match, so that the stroke length of the seismic isolation damper D1 can be efficiently increased, which is preferable.

Further, the damper-side bracket 18 only moves toward and away from the reaction wall 17b of the fixed-side bracket 17 in the left-right direction in FIG. The pressing load acting on the contact surfaces between the friction plates 22 and 23 of the friction damper FD does not change.

Therefore, when a load acting on the first rod 20 and the second rod 21 in the left-right direction in FIG. Then, the first rod 20 and the second rod 21 do not move relative to each other and act as rigid rods. A frictional force generated between the plates 22 and 23 exerts a resistance force that prevents the expansion and contraction. Since the damper-side bracket 18 only moves toward or away from the reaction force wall 17b of the fixed-side bracket 17 in the left-right direction in FIG. Also, the frictional force generated between the friction plates 22 and 23 of the friction damper FD is constant. Therefore, the characteristic of the load generated with respect to the expansion/contraction speed of the friction damper FD is such that the generated load (frictional force) becomes constant when expansion/contraction starts, as shown in FIG. Although not shown, an elastic body such as a spring may be provided between the friction plate 22 and the first rod 20 to press the friction plate 22 against the friction plate 23. An elastic member such as a spring may be provided between and to press the friction plate 23 against the friction plate 22 .

In this embodiment, the friction damper FD is constrained in one direction to expand and contract by guiding the movement of the damper-side bracket 18 with respect to the ground G by the linear guide 19 as a guide member. The friction damper FD itself may restrict its expansion/contraction direction in one direction. Specifically, the friction damper FD includes a cylinder, a rod movably inserted into the cylinder, a piston provided on the rod, a friction member mounted on the outer circumference of the piston and in sliding contact with the inner circumference of the cylinder, An annular rod guide is provided in the cylinder and guides the movement of the rod with respect to the cylinder. The rod is slidably inserted into the rod guide, and the friction member provided on the outer periphery of the piston comes into sliding contact with the cylinder. The expansion and contraction direction may be constrained only in the axial direction of the rod. The friction damper FD may be restrained in one direction of expansion and contraction regardless of whether it is by itself or by another device, and one end and the other end may be relatively rotatable about an axis.

The seismic isolation damper D1 configured in this way operates as follows. First, the operation when the damping force generated by the hydraulic damper OD is less than or equal to the predetermined load will be described. In this case, since the tensile or compressive load acting on the friction damper FD is equal to the damping force generated by the hydraulic damper OD, the friction damper FD behaves as a rigid rod without expanding or contracting. In such a situation, the force exerted by the seismic isolation damper D1 becomes equal to the damping force generated by the hydraulic damper OD. On the other hand, when the damping force generated by the hydraulic damper OD exceeds the predetermined load, the load in the tensile or compressive direction acting on the friction damper FD also exceeds the predetermined load. The force generated by the damper D1 is equal to the frictional force exerted by the friction damper FD.

Therefore, when only the hydraulic damper OD expands and contracts, the seismic isolation damper D1 generates a damping force by means of the hydraulic damper OD, and when the friction damper FD expands and contracts, the seismic isolation damper D1 generates the friction of the friction damper FD. A damping force is generated by force.

FIG. 8 shows the relationship between the displacement and the damping force when the hydraulic damper OD is displaced in a constant cycle. If the predetermined load generated by the hydraulic damper OD in FIG. 8 is set slightly smaller than the maximum damping force of the hydraulic damper OD, the hydraulic damper OD expands and contracts and the damping force becomes close to the maximum value in FIG. Friction damper FD begins to expand and contract. As shown in FIG. 9, the frictional force generated by the friction damper FD with respect to displacement has a constant characteristic regardless of the displacement. Therefore, the seismic isolation damper D1 in which the hydraulic damper OD and the friction damper FD are connected in series exhibits a damping force as shown in FIG. Compared to the case, the stroke length increases by the amount of expansion and contraction of the friction damper FD, and the area surrounded by the characteristic line in FIG. 10 becomes much larger, so that more vibration energy can be absorbed.

Therefore, in the seismic isolation damper D1, the friction damper FD as a resistance member is connected in series with the hydraulic damper OD. , the hydraulic damper OD is not subjected to excessive load, the stroke length can be secured without increasing the size and weight of the hydraulic damper OD, and the vibration of the structure S can be suppressed by responding to long-period seismic motion. can. Also, since the maximum damping force of the seismic isolation damper D1 is limited to the frictional force of the friction damper FD, it is possible to prevent damage to the hydraulic damper OD and damage to the structure-side mounting device SB and ground-side mounting device GB. Damage to the seismic damper D1 itself can be prevented. Furthermore, since the maximum damping force of the seismic isolation damper D1 is limited to the frictional force of the friction damper FD, It is also possible to prevent damage to peripheral members of the seismic isolation damper D1, such as the mounting portion.

As described above, the seismic isolation damper D1 of the present invention includes the hydraulic damper OD, the structure-side mounting device SB for mounting the hydraulic damper OD to the structure S so as to be horizontally rotatable, and the hydraulic damper OD horizontally rotatably mounted on the ground. The ground side mounting device GB is attached to G, and the ground side mounting device GB expands and contracts when a load exceeding a predetermined load acts on the expansion and contraction direction with the expansion and contraction direction restrained in one direction, and exerts a resistance force that prevents expansion and contraction. It has a resistance member and a damper-side bracket 18 that connects one end of the resistance member to the hydraulic damper OD, and the resistance member is the friction damper FD.

According to the seismic isolation damper D1 configured in this way, the hydraulic damper OD and the resistance member (friction damper FD) are arranged in series, so the stroke length can be secured, and the resistance member (friction damper FD) is mounted on the ground side. Since it is incorporated in the device GB, buckling of the hydraulic damper OD and the resistance member (friction damper FD) can be prevented. In addition, since the resistance member (friction damper FD) is incorporated in the ground side mounting device GB, a constant resistance force (frictional force) can be exerted even if the vertical distance between the structure S and the ground G changes. .

Furthermore, since the expansion/contraction direction of the resistance member (friction damper FD) is constrained in one direction, there is no residual displacement in directions other than the expansion/contraction direction when the seismic motion ends, so the mounting position of the hydraulic damper OD can be restored. Become.

As described above, according to the seismic isolation damper D1 of the present invention, it is possible to prevent buckling while ensuring a stroke length capable of coping with long-period seismic motion, and the seismic isolation damper D1 and the peripheral members of the seismic isolation damper D1 can be prevented from buckling. A stable damping force can be generated while preventing damage, and the residual displacement of the seismic isolation layer after the end of the earthquake can be suppressed. Although the resistance member is the friction damper FD in the above description, it is not limited to the friction damper FD and may be a steel damper. The extension and contraction of the resistance member means that one end and the other end of the resistance member move relative to each other in the horizontal direction. Naturally, if it is arranged so as to be displaced, it corresponds to expansion and contraction of the resistance member. In other words, regardless of the shape of the friction damper or steel damper as a resistance member, the friction damper or steel damper can be used in such a manner that it deforms or displaces in the stroke direction of the seismic isolation damper D1 to exert resistance. For example, it corresponds to the expansion and contraction of the resistance member.

In addition, in the seismic isolation damper D1 of the present embodiment, the ground-side mounting device GB connects the fixed-side bracket 17 for attaching the resistance member to the ground G and the damper-side bracket 18 to the ground G, and also connects the resistance member to expansion and contraction. and a guide member (linear guide 19) that guides the movement of the accompanying damper-side bracket 18. According to the seismic isolation damper D1 of the present embodiment configured in this manner, the damper-side bracket 18 is guided by the ground G in the movement of the resistance member in the extension/contraction direction. Since it becomes difficult for a bending moment to be input to the member and the hydraulic damper OD, buckling can be effectively prevented. In addition, since the guide member (linear guide 19) can constrain the resistance member in the expansion/contraction direction, the degree of freedom in designing the resistance member is improved.

The predetermined load is a value that determines the load range in which the resistance member expands and contracts and the load range in which the resistance member does not expand and contract. Since the damping force generated by the damper OD also increases, the acceleration acting on the structure S increases due to the damping force generated by the seismic isolation damper D1. The amount of vibration energy absorbed by the damper D1 increases, and the vibration of the structure S can be effectively suppressed. That is, when the expansion and contraction speed of the hydraulic damper OD becomes the second speed Vb, if the predetermined load is set to a load higher than the damping force exerted by the hydraulic damper OD, damage to the hydraulic damper OD can be prevented while the seismic isolation damper The amount of vibration energy absorbed by D1 increases, and the vibration of the structure S can be effectively suppressed.

On the other hand, this predetermined load can be made higher than the damping force of the hydraulic damper OD at the switching point Pa in FIG. 2 and lower than the damping force of the hydraulic damper OD at the switching point Pb. In this case, since the damping force generated by the seismic isolation damper D1 is low, the acceleration acting on the structure S is reduced by exerting the damping force of the seismic isolation damper D1. The habitability in the structure S can be improved. In other words, if a predetermined load is set within the range of the damping force exerted by the hydraulic damper OD when the expansion and contraction speed of the hydraulic damper OD is greater than or equal to the first speed Va and less than or equal to the second speed Vb, can maintain good livability.

As can be understood from the above description, the damping force generated by the seismic isolation damper D1 becomes equal to the resistance force generated by the resistance member (friction damper FD) when the resistance member (friction damper FD) expands and contracts. . That is, the damping force generated by the seismic isolation damper D1 becomes equal to the resistance force generated by the resistance member (friction damper FD) when the resistance member (friction damper FD) expands and contracts, and levels off. Therefore, when the damping force characteristic of the seismic isolation damper D1 has two switching points with respect to the expansion/contraction speed in the same manner as the damping force characteristic of the hydraulic damper OD, and the damping coefficient changes at the switching point. , the relief valve RV in the damping portions V1, V2, V3 of the hydraulic damper OD may be omitted.

Furthermore, in the present embodiment, the resistance member is provided only in the ground side mounting device GB, but the structure side mounting device SB may be provided with the resistance member. In this case, like the seismic isolation damper D2 of the first modified example of the embodiment shown in FIG. It suffices to have the fixed side bracket 25, the damper side bracket 26 connected to the hydraulic damper OD, and the friction damper FD as a resistance member.

The stationary bracket 25 includes a base 25a fixed to the structure S and a reaction wall 25b attached to the base 25a. The damper-side bracket 26 has a shaft 26a inserted into the eye-shaped bracket 10a of the hydraulic damper OD, and the hydraulic damper OD is allowed to rotate in the horizontal direction around the shaft 26a.

The damper side bracket 26 is attached to the base 25a of the fixed side bracket 25 by a linear guide 27 as a guide member. The movement of the damper-side bracket 26 is guided by a linear guide 27 as a guide member, and can move in the horizontal direction in FIG.

In this way, since the friction damper FD as a resistance member is provided in both the ground-side mounting device GB and the structure-side mounting device SB, it becomes easier to secure the stroke length of the seismic isolation damper D2, and the resistance member becomes stronger. Since the length can be shortened, the buckling prevention effect of the seismic isolation damper D2 is enhanced.

Thus, when the friction damper FD as a resistance member is provided in both the ground side mounting device GB and the structure side mounting device SB, the seismic isolation damper D3 in the second modification of the embodiment shown in FIG. is provided with a ground side locking device 30 for switching between enabling/disabling expansion and contraction of the resistance device of the ground side mounting device GB, and a structure side locking device 31 for switching enabling/disabling expansion and contraction of the resistance member of the structure side mounting device SB, The value of the predetermined load at which the resistance member of the ground side mounting device GB starts to expand and contract may differ from the value of the predetermined load at which the resistance member of the structure side mounting device SB starts to expand and contract.

The ground-side locking device 30 is provided in the base 17a and includes a pin 30a that can be inserted into a hole (not shown) provided in the damper-side bracket 18, and a drive source 30b that inserts and removes the pin 30a into and out of the hole. Then, the ground-side locking device 30 inserts the pin 30a into the hole to disable the movement of the damper-side bracket 18, thereby setting the friction damper FD in a non-expandable locked state. On the contrary, the ground-side locking device 30 allows the damper-side bracket 18 to move when the pin 30a is pulled out of the hole, and puts the friction damper FD into an expandable and contractable free state. The structure-side locking device 31, like the ground-side locking device 30, includes a pin 31a that can move in and out of a hole (not shown) provided in the damper-side bracket 26, and a drive source 31b that inserts and removes the pin 31a into and out of the hole. All you have to do is The specific structures of the ground-side locking device 30 and the structure-side locking device 31 described above are only examples, and the ground-side locking device 30 and the structure-side locking device 31 are arranged in a state in which the resistance member can be expanded and contracted and a state in which the resistance member is not expanded and contracted. Any device can be used as long as it can switch between states.

In the seismic isolation damper D3 in the second modified example configured in this manner, the resistance member in the structure-side mounting device SB and the resistance member in the ground-side mounting device GB are independently switched between the locked state and the free state. It is possible, and the resistance force of the resistance member in the structure-side mounting device SB and the resistance member in the ground-side mounting device GB is different. When the resistance member in the structure side mounting device SB is locked and the resistance member in the ground side mounting device GB is made free, and when the resistance member in the structure side mounting device SB is freed and the resistance member in the ground side mounting device GB is locked The characteristics of the maximum damping force of the seismic isolation damper D2 and the damping force with respect to displacement can be changed. Therefore, according to the seismic isolation damper D3 configured in this way, the characteristics of the damping force can be changed according to the seismic motion, and the vibration of the structure S can be effectively suppressed. In controlling the drive source 30b of the ground-side locking device 30 and the structure-side locking device 31, it is necessary to increase the damping force if the seismic motion is large. The ground-side locking device 30 and the structure-side locking device 31 may be controlled according to the magnitude of the detected seismic motion.

Also, the ground side mounting device GB1 may be configured like the seismic isolation damper D4 of the third modified example shown in FIG. The ground-side mounting device GB1 includes a damper-side bracket 32 and a friction damper FD1 as a resistance member. 13 and 14, the friction damper FD1 faces a plate 33 fixed to the ground G, a slider 34 slidable on the plate 33 only in the lateral direction in FIG. 13, and the slider 34 of the plate 33. It comprises a friction plate 35 provided on the opposing surface and a friction plate 36 provided on the slider 34 and brought into contact with the friction plate 35 . As shown in FIG. 14, the plate 33 is provided with grooves 33a on its sides. The slider 34 has a channel shape, both ends of which are fitted into the grooves 33a, and is attached to the plate 33 in such a manner that it is allowed to move in only one direction . If the friction plate 35 is brought into direct contact with the slider 34 to generate the friction force, the friction plate 36 can be omitted. , the friction plate 35 can be omitted. Although not shown, an elastic body such as a spring may be provided between the friction plate 35 and the plate 33 to press the friction plate 35 against the friction plate 36. An elastic body such as a spring may be provided to press the plate 36 against the friction plate 35 .

Also, the damper-side bracket 32 is a connecting portion provided with a reaction force portion 32a attached to the slider 34 and a shaft 32c provided on the side portion of the reaction force portion 32a and inserted into the eye-shaped bracket 3a of the hydraulic damper OD. 32b.

As described above, in the seismic isolation damper D4 of the third modification, the friction damper FD1 as a resistance member constrains the expansion and contraction direction of the friction damper FD1 itself in one direction, and the movement of the damper-side bracket 32 is also prevented by the friction damper FD1. It is restrained so that it is permitted only in the same direction as the expansion and contraction direction of the FD1 and cannot move in other directions.

Even in the seismic isolation damper D4 configured in this way, the hydraulic damper OD, the structure-side mounting device SB that mounts the hydraulic damper OD to the structure S so as to be horizontally rotatable, and the hydraulic damper OD that is horizontally rotatable. The ground side mounting device GB is attached to the ground G so that the ground side mounting device GB1 can be attached to the ground G, and the ground side mounting device GB1 is constrained in one direction for expansion and contraction, and when a load exceeding a predetermined load acts in the expansion and contraction direction, the ground side mounting device GB1 expands and contracts and has a resistance force that prevents expansion and contraction. and a damper-side bracket 32 connecting one end of the resistance member to the hydraulic damper OD. The resistance member is a friction damper FD.

According to the seismic isolation damper D4 configured in this way, the hydraulic damper OD and the resistance member (friction damper FD1) are arranged in series, so the stroke length can be secured, and the resistance member (friction damper FD1) is mounted on the ground side. Since it is incorporated in the device GB, buckling of the hydraulic damper OD and the resistance member (friction damper FD1) can be prevented. In addition, since the resistance member (friction damper FD1) is incorporated in the ground side mounting device GB1, a constant resistance force (frictional force) can be exhibited even if the vertical distance between the structure S and the ground G changes. .

Furthermore, since the expansion/contraction direction of the resistance member (friction damper FD1) is constrained in one direction, when the seismic motion ends, there is no residual displacement in directions other than the expansion/contraction direction, and the residual displacement in the seismic isolation layer is suppressed. The mounting posture of the damper OD is restored.

As described above, according to the seismic isolation damper D4 of the present invention, it is possible to prevent buckling while ensuring a stroke length that can cope with long-period seismic motion, to generate a stable damping force, and to increase the seismic isolation layer after the earthquake. Residual displacement can be suppressed. Although the resistance member is the friction damper FD1 in the above description, it is not limited to the friction damper FD1. It may consist of Furthermore, in the present embodiment, the resistance member is provided only in the ground side mounting device GB1, but the structure side mounting device SB may be provided with the resistance member. Similarly, it becomes easy to ensure the stroke length of the seismic isolation damper D4, and the length of the resistance member can be shortened, so that the buckling prevention effect of the seismic isolation damper D4 is enhanced.

Although preferred embodiments of the invention have been described in detail above, modifications, variations and changes are possible without departing from the scope of the claims.

Reference numerals 17, 25: fixed side bracket, 18, 26, 32: damper side bracket, 19: linear guide (guide member), 31: structure side lock device, 30: ground side lock Device, D1, D2, D3, D4... seismic isolation damper, G... ground, GB1... ground side mounting device, FD, FD1... friction damper, OD... hydraulic damper, S.・・・Structure, SB・・・Structure side mounting device

Claims (3)

a hydraulic damper;
a structure-side mounting device that mounts the hydraulic damper to a structure so as to be rotatable in a horizontal direction;
a ground-side mounting device that mounts the hydraulic damper to the ground so as to be rotatable in the horizontal direction;
The structure-side mounting device and the ground-side mounting device are composed of a resistance member that exerts a resistance force that prevents expansion and contraction by constraining the direction of expansion and contraction in one direction, and a damper side that connects one end of the resistance member to the hydraulic damper. a bracket and
The resistance member is a friction damper or a steel damper, and expands and contracts only when the damping force generated by the hydraulic damper exceeds a predetermined load,
The structure-side mounting device includes the resistance member, the damper-side bracket that connects one end of the resistance member to the hydraulic damper, and a structure-side lock device that switches whether the resistance member can be extended or retracted. ,
The ground-side mounting device includes the resistance member, the damper-side bracket that connects one end of the resistance member to the hydraulic damper, and a ground-side locking device that switches whether the resistance member can be extended or retracted,
The predetermined load of the resistance member in the structure-side mounting device is different from the predetermined load of the resistance member in the ground-side mounting device.
A seismic isolation damper characterized by: a hydraulic damper;
a structure-side mounting device that mounts the hydraulic damper to a structure so as to be rotatable in a horizontal direction;
a ground-side mounting device that mounts the hydraulic damper to the ground so as to be rotatable in the horizontal direction;
One or both of the structure-side mounting device and the ground-side mounting device include a resistance member that exerts a resistance force that prevents expansion and contraction by constraining the direction of expansion and contraction in one direction, and one end of the resistance member that is connected to the hydraulic damper. and a damper side bracket,
The hydraulic damper divides the expansion and contraction speed into a low speed lower than the first speed, a medium speed higher than the first speed and lower than the second speed, and a high speed higher than the second speed. has a damping force characteristic in which the coefficient is switched and the damping coefficient is maximized when the expansion and contraction speed is in the medium speed range;
The resistance member is a friction damper or a steel damper, and expands and contracts only when the damping force generated by the hydraulic damper exceeds a predetermined load,
The predetermined load is set to a load higher than the damping force exerted by the hydraulic damper when the expansion/contraction speed becomes the second speed.
A seismic isolation damper characterized by: One or both of the structure-side mounting device and the ground-side mounting device connect the fixed-side bracket for mounting the resistance member to the structure or the ground, and the damper-side bracket to the structure or the ground. The seismic isolation damper according to claim 1 or 2, further comprising a guide member that guides movement of the damper-side bracket accompanying expansion and contraction of the resistance member.

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