JP6297454B2 - Seismic isolation damper - Google Patents

Description

  The present invention relates to a seismic isolation damper that is provided between a ground and a structure together with a seismic isolation bearing and suppresses a relative displacement between the ground and the structure.

  As a conventional damper, for example, one disclosed in Patent Document 1 is known. This damper is a rotating mass damper having a rotating mass, and is used as a structure damping device. The rotary mass damper includes an inner cylinder, a ball screw having a screw shaft and a ball nut, and a cylindrical rotary mass disposed outside the ball screw. One end of the inner cylinder is connected to the first part of the structure, one end of the screw shaft is connected to the second part of the structure, and the other end of the screw shaft is movable to the other end of the inner cylinder Is fitted. The ball nut is screwed onto the screw shaft via a large number of balls, and the rotating mass is connected to the ball nut. A viscous material is filled between the inner cylinder and the rotating mass.

  With the above configuration, when the first part and the second part are relatively displaced as the structure vibrates during an earthquake, the inner cylinder and the screw shaft connected to each other relatively move linearly. The rotation mass is rotated by converting the movement into the rotation movement of the ball nut by the action of the ball screw. Along with the rotation of the rotating mass, the rotational inertial mass effect due to the rotating mass and the viscous damping effect due to the viscous body are exerted, whereby the relative displacement between the first part and the second part is suppressed, and the vibration of the structure is suppressed. It is suppressed.

JP 2014-132135 A

  As described above, in Patent Document 1, a rotary mass damper is used as a structure damping device. On the other hand, when a rotary mass damper is used as a seismic isolation damper for a structure, there are the following problems. For example, as a seismic isolation device for a structure between the structure and the ground, the seismic isolation support for allowing the structure to move in the horizontal direction relative to the ground and the energy of shaking are absorbed, and the ground and the structure When combined with a rotating mass damper for suppressing relative displacement (hereinafter simply referred to as “relative displacement”), if the structure is shaken and a relative displacement occurs during an earthquake, the structure of the rotating mass damper described above rotates. The mass is driven and rotated regardless of the magnitude of the relative displacement.

  For this reason, the reaction force of the rotary mass damper acts on the ground and the structure in a range where the relative displacement is relatively small, which affects the movement of the structure. By allowing the movement of the structure and extending the period of shaking of the structure, the function of making the shaking of the ground difficult to be transmitted to the structure and reducing the shaking of the structure may be hindered.

  The present invention has been made to solve such a problem, and by making the rotational inertial mass effect by the rotating mass variable according to the magnitude of the relative displacement between the ground and the structure, the seismic isolation is achieved. An object of the present invention is to provide a seismic isolation damper capable of preventing an excessive relative displacement during an earthquake while ensuring a seismic isolation function of a bearing.

  In order to achieve the above object, the invention according to claim 1 is provided with a seismic isolation bearing between the ground and the structure, and is used for seismic isolation to suppress relative displacement between the ground and the structure during an earthquake. A damper with one end connected to one of the ground and the structure, one end connected to the other of the ground and the structure, and the other end movably fitted to the other end of the cylinder. As the screw shaft moves axially with respect to the cylindrical body, the screw shaft is coaxially disposed on the outside of the screw shaft and is screwed onto the screw shaft via a number of freely rolling balls. A rotating nut that is coaxially disposed on the outside of the cylinder and the ball nut, and an inner peripheral surface of the rotating mass that is integrally provided with an interval between each other in the axial direction. Between a pair of ring-shaped torque transmission parts and a ball nut and rotating mass Between the pair of torque transmission parts, the pair of torque transmission parts are arranged at a predetermined interval, are provided so as to be non-rotatable and movable in the axial direction with respect to one of the ball nut and the rotation mass, and the other. A ring-shaped drive member that is screwed onto the ball nut, and the drive member moves in the axial direction along with the rotation of the ball nut, thereby pressing the torque of the ball nut while pressing one of the pair of torque transmitting portions. Is transmitted to the rotating mass via one torque transmitting portion, thereby rotating the rotating mass.

This seismic isolation damper is provided with a seismic isolation support between the ground and the structure, and constitutes a seismic isolation device. In the present invention, a cylindrical body, a ball screw including a screw shaft and a ball nut, The rotary mass damper includes a rotary mass and the like. The cylinder is connected to one of the ground and the structure, and the screw shaft is connected to the other of the ground and the structure. Further, a pair of ring-shaped torque transmission portions are integrally provided on the inner peripheral surface of the rotary mass, and a ring-shaped drive member is provided between the ball nut and the rotary mass and between the pair of torque transmission portions. Is provided. As described above, the driving member is provided in the following configuration pattern A or B with respect to the ball nut and the rotating mass.
A. The drive member is provided so as not to rotate with respect to the ball nut and to be movable in the axial direction, and is screwed into the rotary mass.
B. The drive member is provided so as not to rotate with respect to the rotary mass and to be movable in the axial direction, and is screwed into the ball nut.

  In this seismic isolation damper, if a relative displacement between the ground and the structure occurs (hereinafter simply referred to as “relative displacement”) during an earthquake, the relative displacement is allowed by the action of the seismic isolation bearing, and the period of the shaking of the structure The seismic isolation function that reduces the vibration transmitted from the ground to the structure is exhibited.

  Also, when a relative displacement occurs during an earthquake, the cylinder connected to one of the ground and the structure and the screw shaft connected to the other relatively linearly move in the axial direction, and this linear motion is the action of the ball screw. The ball nut is rotated by being converted into the rotational motion of the ball nut. The rotation direction of the ball nut at this time depends on the direction of relative displacement, and the rotation amount of the ball nut is proportional to the magnitude of the relative displacement.

  When the ball nut rotates in this way, when the configuration pattern is A, the drive member rotates integrally with the ball nut and rotates with respect to the rotating mass by screwing with the rotating mass. It moves in the axial direction with a movement amount corresponding to the amount, that is, relative displacement. Thereafter, when the relative displacement reaches a predetermined value, for example, the driving member comes into contact with one torque transmission portion and presses the torque transmission portion. As a result, the torque of the ball nut is transmitted to the rotating mass via the drive member and the torque transmitting portion, whereby the rotating mass rotates and the rotational inertial mass effect by the rotating mass is exhibited.

  On the other hand, when the configuration pattern of the driving member is B, when the ball nut rotates, the driving member is prevented from rotating by the rotating mass, and is screwed with the ball nut to the rotating mass. It moves in the axial direction with a movement amount corresponding to the rotation amount (relative displacement) of the nut. Thereafter, when the relative displacement reaches a predetermined value, for example, the driving member comes into contact with one torque transmission portion and presses the torque transmission portion. As a result, the driving member starts to rotate integrally with the ball nut, and at the same time, the torque of the ball nut is transmitted to the rotating mass via the driving member and the torque transmitting portion, whereby the rotating mass rotates, and the rotating mass rotates. Inertial mass effect is exhibited.

  As described above, according to the present invention, until the relative displacement reaches a predetermined value at the time of an earthquake, the ball nut rotates, but the rotating mass does not rotate and the rotating inertial mass effect is not exhibited. Thus, in a small range until the relative displacement reaches a predetermined value, it is possible to avoid the reaction force from the rotary mass damper acting on the structure and affecting the movement of the structure. The function can be secured satisfactorily.

  On the other hand, after the relative displacement reaches a predetermined value, the torque of the ball nut is transmitted to the rotating mass via the driving member and the torque transmitting unit, so that the rotating mass rotates and the rotational inertial mass effect is exhibited. . As a result, excessive relative displacement during an earthquake can be prevented by absorbing the energy of the shaking of the earthquake.

  According to a second aspect of the present invention, in the seismic isolation damper according to the first aspect, the drive member is configured to abut on the torque transmitting portion when the amount of movement in the axial direction reaches a predetermined amount. The driving mechanism further includes a lock mechanism that locks the driving member to the torque transmission unit when the driving member contacts the torque transmission unit.

  According to this configuration, when the amount of movement of the drive member in the axial direction reaches a predetermined amount, the rotary mass is driven in a state where the drive member contacts the torque transmission unit and directly presses the torque transmission unit. . Further, the drive member is locked to the torque transmission unit by the lock mechanism when it contacts the torque transmission unit. Thus, after the driving member comes into contact with the torque transmitting portion, that is, after the relative displacement reaches a predetermined value, the driving member and the torque transmitting portion are integrated with each other regardless of a change in the magnitude or direction of the subsequent relative displacement. Is maintained in the state.

  As a result, after the relative displacement reaches the predetermined value, the rotational mass is driven almost continuously and the rotational inertial mass effect is obtained, so that it is possible to more effectively prevent excessive relative displacement during an earthquake. it can. In addition, after the drive member is locked, even if the direction of relative displacement is reversed, the drive member does not move and does not contact the other torque transmission unit. As compared with the case of repeatedly abutting, the impact load and load acting on both members at the time of abutting can be reduced, and noise and wear of both members due to the impact can be suppressed.

  The invention according to claim 3 is the seismic isolation damper according to claim 1, further comprising a pair of spring members respectively disposed between the drive member and the pair of torque transmitting portions, wherein the drive member is arranged in the axial direction. As it moves, it is configured to press the torque transmission part via the spring material.

  According to this configuration, since the driving member presses the torque transmission part via the spring material, compared with the case where the driving member abuts on the torque transmission part, the impact load and load acting on both members can be reduced, Such wear and noise can be suppressed. Further, as the amount of movement of the drive member increases, the amount of deformation of the spring material increases, and accordingly, the pressing force acting on the torque transmitting portion increases, whereby the torque transmitted to the rotating mass increases. Therefore, as the relative displacement increases, the rotational inertial mass effect can be increased, and the relative displacement during an earthquake can be suppressed more appropriately according to the actual relative displacement magnitude.

  The invention according to claim 4 is the seismic isolation damper according to claim 3, wherein the pair of spring members are in contact with the drive member and the pair of torque transmission portions in a state where the drive member is in the neutral position, and are compressed in advance. A load is applied.

  According to this configuration, when the relative displacement is 0 and the driving member is in the neutral position, the pressing force acting on each of the pair of torque transmission portions is a predetermined compression load (hereinafter referred to as “preliminary” applied to the spring material in advance). Equal to load). From this state, when the drive member moves from the neutral position with the occurrence of relative displacement, one spring material is compressed by the drive member, so that the compression load of the spring material increases and at the same time the other spring material By extending following the drive member, the compression load of the spring material is reduced. As a result, the increase in the compression load of one spring material and the decrease in the compression load of the other spring material are canceled out, so that the pressing force of the torque transmission part is kept approximately equal to the preload, and accordingly Thus, the transmission torque to the rotating mass and the rotating inertial mass effect are also kept substantially constant.

  Thereafter, as the relative displacement increases, when the amount of movement of the drive member reaches a predetermined amount, the extension of the other spring material reaches a limit, so that the drive member moves away from the other spring material. After that, the drive member continues to compress one spring material, and the pressing force of the torque transmission portion increases as the amount of compression of the spring material increases. The inertial mass effect is increased.

  As described above, according to the present invention, in a range where the relative displacement is small, a substantially constant and relatively small rotational inertial mass effect is obtained, and after the relative displacement exceeds this range, as the relative displacement increases, The rotational inertial mass effect can be increased. Therefore, suppression of relative displacement during an earthquake can be performed more appropriately according to the actual magnitude of relative displacement.

  The invention according to claim 5 is the seismic isolation damper according to claim 3 or 4, further comprising a sliding member interposed between the drive member and the pair of spring members.

  According to this structure, the impact load and load which act on a drive member and a spring material can be reduced by the sliding material interposed between a drive member and each spring material, and damage and wear of both members can be suppressed.

  The invention according to claim 6 is the seismic isolation damper according to any one of claims 1 to 5, further comprising a viscous body filled between the rotating mass and the cylindrical body.

  According to this configuration, when the rotating mass rotates, the viscous damping effect is exhibited by the viscous material filled between the rotating mass and the cylinder. In this case, the larger the differential rotational speed between the rotating mass filled with the viscous body and the cylindrical body, the larger the viscous damping effect is obtained. As described above, when the rotating mass rotates, the viscous damping effect of the viscous body is added to the rotating inertial mass effect of the rotating mass, so that the effect of suppressing the relative displacement can be further enhanced.

  A seventh aspect of the present invention provides the seismic isolation damper according to any one of the first to sixth aspects, wherein the second rotatable rotating mass is coaxially disposed outside the rotating mass, and is second. A pair of ring-shaped second torque transmitting portions that are integrally provided on the inner peripheral surface of the rotating mass and are spaced apart from each other in the axial direction, and a pair of second torque transmission portions between the rotating mass and the second rotating mass. A ring-shaped first ring is disposed between the torque transmission portions at a predetermined interval, is provided so as not to rotate with respect to one of the rotating mass and the second rotating mass and is movable in the axial direction, and is screwed to the other. 2, and the second drive member moves in the axial direction as the rotary mass rotates, so that one of the pair of second torque transmission parts is pressed while the rotary mass is rotating. Torque is applied to the second time through one of the second torque transmission parts. By transferring the mass, characterized in that it is configured to rotate the second rotating mass.

  According to this configuration, the cylindrical second rotary mass is coaxially disposed outside the rotary mass, and between the rotary masses, the drive member and the torque transmission unit between the ball nut and the rotary mass are arranged. The second drive member and the second torque transmission unit are provided in the same configuration as in FIG. Therefore, if the relative displacement in the same direction continues after obtaining the rotational inertial mass effect of the rotating mass by driving the rotating mass by the driving member and the torque transmitting unit, the second driving member and the second torque transmitting unit The rotational inertial mass effect by the second rotating mass is further added by driving the second rotating mass. As a result, the rotational inertial mass effect can be increased in two stages according to the actual occurrence state of the relative displacement, and the relative displacement can be appropriately suppressed particularly during a huge earthquake.

It is a top view which shows the example of installation of the seismic isolation apparatus which has the damper for seismic isolation to which this invention is applied, and a seismic isolation support. It is a figure which shows the installation condition of the seismic isolation apparatus of FIG. It is a longitudinal cross-sectional view of the rotation mass damper by 1st Embodiment which comprises the seismic isolation damper. FIG. 4 is a cross-sectional view taken along line IV-IV of the rotary mass damper of FIG. 3. It is a figure which shows the torque transmission characteristic of the rotation mass damper of FIG. It is a figure which shows the vibration model of the rotation mass damper of FIG. It is a longitudinal cross-sectional view of the rotary mass damper which has a drive member of a structure different from FIG. It is sectional drawing which follows the line VIII-VIII of the rotary mass damper of FIG. It is a fragmentary longitudinal cross-sectional view of the rotary mass damper by the modification of 1st Embodiment. It is a figure which shows the torque transmission characteristic of the rotary mass damper of FIG. It is a longitudinal cross-sectional view of the rotary mass damper by 2nd Embodiment. It is a figure which shows the torque transmission characteristic of the rotary mass damper of FIG. It is a longitudinal cross-sectional view of the rotary mass damper by 3rd Embodiment. It is a figure which shows the vibration model of the rotation mass damper of FIG. It is a longitudinal cross-sectional view of the rotary mass damper by 4th Embodiment. It is a figure which shows the torque transmission characteristic of the rotary mass damper of FIG. It is a longitudinal cross-sectional view of the rotary mass damper by 5th Embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an example in which a seismic isolation device including a seismic isolation damper to which the present invention is applied is installed between a foundation 1 and a building 2. This seismic isolation device includes a seismic isolation bearing 3 and a rotary mass damper 10 as a seismic isolation damper. As shown in FIG. 1, a total of nine seismic isolation bearings 3 are arranged in a matrix on the entire plane of the building 2. Two rotating mass dampers 10 are arranged at four corners of the building 2 so as to surround the seismic isolation bearings 3 in total.

  As shown in FIG. 2, a steel frame base 9 made of H-shaped steel is integrally provided below the base 6 of the building 2. The seismic isolation bearing 3 is of a rolling type, for example, and includes a rollable ball 3a attached to the lower surface of the steel frame 9 and a rolling surface 4 provided on the foundation 1 on which the ball 3a rolls. Yes. The rolling surface 4 is formed in an inverted conical shape slightly inclined with respect to the horizontal plane so that the ball 3a can return to its original position under its own weight after an earthquake. Further, a metal ring-shaped stopper 5 that restricts rolling of the ball 3 a is provided on the outer peripheral portion of the rolling surface 4.

  With the above configuration, when the building 2 shakes during an earthquake, the ball 3a rolls on the rolling surface 4 from the neutral position shown in FIG. As a result, the horizontal movement of the building 2 at the time of the earthquake is allowed, and the period of the shaking of the building 2 is extended, thereby making it difficult to transmit the shaking of the foundation 1 to the building 2 and suppressing the shaking of the building 2. Seismic function is demonstrated.

  On the other hand, the rotary mass damper 10 is provided between the bracket 7 fixed to the lower surface of the steel frame base 9 and the bracket 8 fixed to the upper surface of the foundation 1. FIG. 3 shows a rotary mass damper 10A according to the first embodiment of the present invention. The rotating mass damper 10A includes an inner cylinder 21, a ball screw 22, a rotating mass 23, and a torque transmission mechanism 24. The inner cylinder 21 is made of a cylindrical steel material having one end opened, and the other end of the inner cylinder 21 is provided with a universal joint having a friction that does not move with the torque generated by the rotating mass damper 10A. A first flange 25 is attached.

  The ball screw 22 includes a screw shaft 22a, a number of balls 22b, a ball nut 22c, and the like. The screw shaft 22a is disposed coaxially with the inner cylinder 21, and is fitted to one end of the inner cylinder 21 that is open at one end so as to be movable in the axial direction. A second flange 26 is attached to the other end of the screw shaft 22a via a universal joint having a friction that does not move with the torque generated by the rotary mass damper 10A.

  The ball nut 22c is supported by one end portion of the inner cylinder 21 through a bearing 27 so as to be rotatable and immovable in the axial direction. In addition, screw grooves are formed on the outer peripheral surface of the screw shaft 22a and the inner peripheral surface of the ball nut 22c, and a large number of balls 22b are accommodated between both screw grooves. The ball nut 22c is interposed via the balls 22b. And screwed to the screw shaft 22a. With the above configuration, when the screw shaft 22a moves relative to the inner cylinder 21 in the axial direction, the relative linear motion is converted into the rotational motion of the ball nut 22c by the action of the ball screw 22 (hereinafter, “ The ball nut 22c is rotated by the “rotational conversion operation of the ball screw 22”. The rotation direction of the ball nut 22c at this time depends on the direction of the relative linear motion, and the amount of rotation depends on the distance of the relative linear motion and the pitch of the thread groove.

  The rotary mass 23 is made of a material having a large specific gravity, for example, iron, and is formed in a cylindrical shape. The rotating mass 23 is disposed outside the inner cylinder 21 and the ball screw 22 so as to cover the whole, and is rotatably supported by the inner cylinder 21 via a bearing 28.

  The torque transmission mechanism 24 transmits the torque (rotation) of the ball nut 22c to the rotary mass 23 and drives the rotary mass 23, and includes a drive member 31, a pair of torque transmission units 32 and 32, and the like. .

  As shown in FIG. 4, the drive member 31 has a ring shape and is disposed between the ball nut 22c and the rotary mass 23. The drive member 31 is splined to the inner ball nut 22c and screwed to the outer rotary mass 23. Match.

  Specifically, four spline holes 31a are formed on the inner peripheral surface of the drive member 31 at equal intervals of 90 degrees in the circumferential direction. On the other hand, on the outer peripheral surface of the ball nut 22c, four spline teeth 22d corresponding to the spline holes 31a and extending in the axial direction are formed, and the spline holes 31a are fitted into the respective spline teeth 22d. Due to such spline coupling, the drive member 31 is not rotatable with respect to the ball nut 22c and is movable in the axial direction.

  On the other hand, a male screw 31b is formed on the outer peripheral surface of the drive member 31, and a female screw 23a is formed on the inner peripheral surface of the rotating mass 23 in the axial direction range corresponding to the ball nut 22c. The male screw 31b is screwed. Due to the spline coupling with the ball nut 22c and the screw engagement with the rotary mass 23 as described above, the drive member 31 rotates along with the spline teeth 22d while rotating integrally with the ball nut 22c. It moves in the axial direction relative to the nut 22c and the rotating mass 23. The moving direction of the driving member 31 at this time depends on the rotating direction of the ball nut 22c, and the moving amount of the driving member 31 depends on the rotating amount of the ball nut 22c and the pitch of the male screw 31b.

  The pair of torque transmitting portions 32 and 32 are ring-shaped members integrally provided on the inner peripheral surface of the rotary mass 23, and are axially positioned at positions corresponding to both ends of the ball nut 22 c on both sides of the drive member 31. They are spaced apart from each other in the direction.

  As shown in FIG. 2, the rotary mass damper 10 </ b> A having the above-described configuration has the first flange 25 fixed to the bracket 7 on the building 2 side and the second flange 26 fixed to the bracket 8 on the foundation 1 side. And between the buildings 2.

  Next, the operation of the rotary mass damper 10A configured as described above will be described with reference to FIG. FIG. 5 shows the relationship between the movement amount Xr from the neutral position of the drive member 31 and the transmission torque Tr transmitted from the ball nut 22 c to the rotary mass 23.

  During normal times when no earthquake occurs, the rotary mass damper 10A is in the neutral state shown in FIG. 3, and the drive member 31 is located at a neutral position between the torque transmission parts 32 and 32, and each torque transmission. The size of the gap between the portion 32 is a predetermined amount G1.

  When a relative displacement DR in the horizontal direction occurs between the foundation 1 and the building 2 during the earthquake, the inner cylinder 21 and the screw shaft 22a connected to the building 2 and the foundation 1 respectively have the same amount in the same direction as the relative displacement DR. The ball nut 22c is rotated by a rotational conversion operation of the ball screw 22 that moves relatively linearly in the axial direction.

  When the ball nut 22c rotates, the drive member 31 rotates from the neutral position (Xr = 0) while rotating integrally with the ball nut 22c by the spline coupling with the ball nut 22c and the screw engagement with the rotation mass 23 described above. Move in the direction (for example, to the right of FIG. 3). Until the relative displacement DR reaches a predetermined value, the moving amount Xr of the driving member 31 is smaller than the predetermined amount G1, and the driving member 31 does not contact the torque transmitting portion 32. Is 0, and the rotating mass 23 does not rotate (point O1 to point a1 in FIG. 5).

  Thereafter, when the relative displacement DR reaches a predetermined value, the movement amount Xr of the driving member 31 becomes equal to the predetermined amount G1, and the driving member 31 comes into contact with one torque transmission portion 32 (point a1). By this contact, the movement of the drive member 31 is blocked by the torque transmission unit 32, and the drive member 31 directly presses the torque transmission unit 32.

  As a result, the torque of the ball nut 22c is transmitted to the rotating mass 23 via the driving member 31 and the torque transmitting portion 32, whereby the rotating mass 23 is driven and the rotational inertial mass effect is exhibited. Further, the transmission torque Tr at this time increases in accordance with the pressing force of the torque transmission unit 32, thereby obtaining a large rotational inertial mass effect (point b1).

  Thereafter, when the direction of the relative displacement DR is reversed, the ball nut 22c rotates in the opposite direction, whereby the transmission torque Tr decreases to 0 and the drive member 31 moves in the opposite direction (for example, to the left). As a result, the torque transmission unit 32 moves away from the torque transmission unit 32 (point c1) and passes through the neutral position toward the other torque transmission unit 32.

  The subsequent operation is the same as above except that the direction is different, and when the relative displacement DR in the opposite direction reaches a predetermined value, the movement amount Xd of the drive member 31 becomes equal to the predetermined amount (−G1) (point) d1), the driving member 31 comes into contact with the other torque transmitting portion 32, and the torque of the ball nut 22c is transmitted to the rotating mass 23 via the driving member 31 and the other torque transmitting portion 32. Driven to exert the rotational inertial mass effect.

  Thereafter, each time the direction of the relative displacement DR is reversed until the relative displacement DR converges, the moving direction of the driving member 31 is switched, and each time the relative displacement DR reaches a predetermined value, the driving member 31 and the torque transmission unit 32 are switched. The rotation mass 23 is repeatedly driven.

  As described above, according to the rotary mass damper 10A of the present embodiment, the ball nut 22c rotates until the relative displacement DR between the foundation 1 and the building 2 at the time of the earthquake reaches a predetermined value, but the rotary mass 23 is It is not driven and the rotary inertia mass effect is not exhibited. Thereby, in the range where the relative displacement DR is small, it is possible to avoid the reaction force from the rotary mass damper 10A acting on the building 2 and affecting the movement of the building 2, and therefore the seismic isolation support 3 has a good seismic isolation function. Can be secured.

  On the other hand, after the relative displacement DR reaches a predetermined value, the rotary mass 23 is driven via the drive member 31 and the torque transmission unit 32, and the rotational inertial mass effect absorbs the vibration energy of the earthquake. It is possible to prevent excessive relative displacement at. For example, the amount of rolling of the ball 3 a of the seismic isolation bearing 3 can be suppressed within an allowable stroke range that does not get over the stopper 5.

  The predetermined value of the relative displacement DR described above corresponds to the size of the relative displacement DR at which the rotary mass 23 starts to rotate. For example, the size of the gap between the drive member 31 and the torque transmission unit 32 (= place It can be easily changed by setting such as quantitative G1). Therefore, by setting a predetermined value of the relative displacement DR according to the assumed level of seismic motion (for example, L1: seismic motion that occurs rarely, L2: seismic motion that occurs extremely rarely, L3: safety margin level), Excessive relative displacement at the time of an earthquake can be prevented appropriately according to the assumed level of ground motion.

  When the rotary mass damper 10A having the above configuration is modeled, it is expressed as shown in FIG. That is, in the rotary mass damper 10A, an inertial connection element consisting of the rotary mass 23 is connected to an elastic element consisting of the screw shaft 22a and the like via a torque transmission mechanism 24 consisting of the drive member 31 and the torque transmission part 32. It has become. Therefore, in a state where the drive member 31 is in contact with the torque transmission unit 32 and torque is transmitted to the rotary mass 23 via the torque transmission mechanism 24, the rotary mass 23 is driven, and a rotational inertial mass effect is obtained. Further, since the inertia connecting element composed of the ball nut 22c is in parallel with the torque transmission mechanism 24 and the rotary mass 23, a small rotational inertia mass effect by the ball nut 22c can be obtained regardless of the operating state of the torque transmission mechanism 24. It is done.

  In the example described above, the drive member 31 is splined to the ball nut 22c and screwed to the rotary mass 23, but this relationship may be reversed. Specifically, as shown in FIGS. 7 and 8, the spline hole 31 c and the female screw 31 d are formed on the outer peripheral surface and the inner peripheral surface of the drive member 31, respectively, and the spline hole 31 c is formed on the inner peripheral surface of the rotary mass 23. The spline teeth 23b may be fitted, and the internal thread 31d may be engaged with the external thread 22e on the outer peripheral surface of the ball nut 22c.

  In this configuration, as the ball nut 22c rotates, the driving member 31 slides in a non-rotating state along the spline teeth 23b of the rotating mass 23, and when the relative displacement DR reaches a predetermined value. By abutting on the torque transmission part 32 and being prevented from moving, it rotates integrally with the ball nut 22 c and drives the rotary mass 23. Therefore, the torque transmission characteristics of the first embodiment shown in FIG. 5 can be obtained similarly.

  Next, a modification of the first embodiment will be described with reference to FIG. In this modification, a lock mechanism 41 that locks the drive member 31 is added to the rotary mass damper 10A described above. As shown in the figure, the lock mechanism 41 includes a pair of fitting portions 42 and 42 provided on the drive member 31, a locking pin 43 provided on each torque transmission portion 32, and the like.

  The pair of fitting portions 42 and 42 are provided integrally with the drive member 31 and protrude on both sides in the axial direction. Each fitting portion 42 has a ring shape concentric with the drive member 31, has a predetermined outer diameter, and is disposed at a circumferential position excluding the spline hole 31a. A locking groove 42 a extending in the circumferential direction is formed on the outer peripheral surface of each fitting portion 42.

  On the other hand, a pin accommodating chamber 44 extending in the radial direction is formed at a predetermined position in the circumferential direction of each torque transmitting portion 32, and the locking pin 43 is accommodated in the pin accommodating chamber 44. The locking pin 43 has a head portion 43 a and a shaft portion 43 b, and the head portion 43 a is engaged with a stepped portion of the pin accommodating chamber 44 in a retaining state. The distal end portion of the shaft portion 43b slightly protrudes from the pin housing chamber 44 into the inner hole 32a of the torque transmitting portion 32, and R is attached to the distal end portion. The locking pin 43 is urged toward the inner hole 32 a by a spring 45 provided in the pin housing chamber 44.

  According to the above configuration, as the driving member 31 moves from the neutral position shown in FIG. 9A in response to the occurrence of the relative displacement DR, the driving member 31 comes into contact with one torque transmission portion 32. At the same time, the fitting portion 42 of the driving member 31 is fitted into the inner hole 32a of the torque transmitting portion 32 (FIG. 5B). In the middle of this fitting operation, the fitting portion 42 abuts against the shaft portion 43b of the locking pin 43 protruding from the inner hole 32a, and presses the locking pin 43 against the biasing force of the spring 45, Retreat inside the pin accommodating chamber 44.

  When the driving member 31 comes into contact with the torque transmitting portion 32 and the fitting portion 42 is completely fitted into the inner hole 32a, the locking groove 42a of the fitting portion 42 matches the locking pin 43. The locking pin 43 protrudes from the pin housing chamber 44 by the urging force of the spring 45, and the shaft portion 43b engages with the locking groove 42a (FIG. 9B). As a result, the drive member 31 is locked in contact with the torque transmission portion 32. When the drive member 31 is thus locked, thereafter, the drive member 31 is held in an integrated state with the torque transmission unit 32 regardless of the magnitude and direction of the relative displacement DR.

  From the above operation, the torque transmission characteristic according to this modification is expressed as shown in FIG. 10, for example. That is, the operation until the drive member 31 contacts the torque transmission unit 32 is the same as that of the first embodiment described above, and when the relative displacement DR reaches a predetermined value (movement amount Xr = predetermined amount G1). When the driving member 31 comes into contact with the torque transmission unit 32, the rotary mass 23 starts to rotate (point b1 in FIG. 10), and the transmission torque Tr increases from 0 according to the pressing force of the torque transmission unit 32.

  Further, when the drive member 31 comes into contact with the torque transmission unit 32, the drive member 31 is locked to the torque transmission unit 32 at the same time, and thereafter, the movement amount Xr becomes independent of the magnitude and direction of the relative displacement DR. The torque of the ball nut 22c is transmitted to the rotating mass 23 through the driving member 31 and the torque transmitting portion 32 that are integral with each other with the predetermined amount G1 (after the point b1).

  As described above, according to this modification, after the relative displacement DR reaches the predetermined value, the driving member 31 comes into contact with the torque transmission unit 32 and is locked, so that the rotary mass 23 is substantially continuously formed. Since it is driven and a rotational inertial mass effect is obtained, excessive relative displacement during an earthquake can be more effectively prevented.

  Further, after the drive member 31 is locked, the drive member 31 does not move and does not come into contact with the other torque transmission portion 32 even if the direction of the relative displacement DR is reversed. Therefore, compared with the first embodiment in which the drive member 31 reciprocates and repeatedly comes into contact with the pair of torque transmission parts 32 and 32, the impact load and load acting on the members 31 and 32 at the time of contact are reduced. It is possible to suppress noise and wear of both members 31 and 32 due to the noise.

  Next, a rotary mass damper 10B according to a second embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 11, the rotary mass damper 10 </ b> B has a pair of spring members 51 between the drive member 31 and the pair of torque transmission parts 32, 32 with respect to the rotary mass damper 10 </ b> A of the first embodiment shown in FIG. 3. 51 is added.

  Each spring member 51 is configured by a ring-shaped disc spring or coil spring, has a predetermined rigidity (spring constant), is disposed outside the ball nut 22c, and is attached to the drive member 31 of each torque transmission unit 32. It is attached to the surface on the opposite side. A sliding member 52 made of fluororesin or the like is attached to the end of each spring member 51 on the side facing the drive member 31. As shown in FIG. 11, when the driving member 31 is in the neutral position, the size of the gap between the driving member 31 and each sliding member 52 is a predetermined amount G2.

  According to the above configuration, when the relative displacement DR occurs, the drive member 31 rotates integrally with the ball nut 22c, as in the rotary mass damper 10A of the first embodiment, and is in the neutral position (Xr = 0) shown in FIG. ) And the spring material 51 does not contact until the relative displacement DR reaches a predetermined value corresponding to the predetermined amount G2. For this reason, the transmission torque Tr to the rotating mass 23 is 0, and the rotating mass 23 is not driven (points O2 to a2 in FIG. 12).

  Thereafter, when the relative displacement DR reaches a predetermined value, the moving amount Xr of the driving member 31 becomes equal to the predetermined amount G2 (point a2), and the driving member 31 comes into contact with one spring member 51 via the sliding member 52. As a result, the drive member 31 is in a state of pressing the torque transmission part 32 via the spring material 51, and the torque of the ball nut 22 c is applied to the rotary mass 23 via the drive member 31, the spring material 51 and the torque transmission part 32. By being transmitted, the rotary mass 23 is driven.

  When the relative displacement DR further increases, the spring material 51 is compressed by the movement of the drive member 31, and the transmission force Tr to the rotary mass 23 is increased by increasing the pressing force of the torque transmission unit 32 in proportion to the compression amount. Increases (point a2 to point b2).

  Thereafter, when the direction of the relative displacement DR is reversed, the ball nut 22c rotates in the opposite direction, thereby reversing the sign of the transmission torque Tr (the driving direction of the rotating mass 23 is switched) (points b2 to c2), As the drive member 31 moves in the opposite direction, the amount of compression of the spring material 51 and the transmission torque Tr decrease. When the relative displacement DR decreases to a predetermined value, the transmission torque Tr becomes 0 and the drive member 31 starts to move away from the spring material 51 (point d2). Thereafter, when the relative displacement DR becomes 0, the drive member 31 returns to the neutral position.

  The subsequent operation is the same as above except that the direction is different. When the relative displacement DR in the opposite direction reaches a predetermined value, the movement amount Xd of the driving member 31 becomes equal to the predetermined amount (−G2), and the driving is performed. When the member 31 abuts against the other spring material 51, the rotary mass 23 is driven (point e2), and as the relative displacement DR increases, the compression amount of the other spring material 51 increases, and accordingly. The transmission torque Tr increases (point f2).

  Thereafter, each time the direction of the relative displacement DR is reversed until the relative displacement DR converges, the moving direction of the driving member 31 is switched, and every time the relative displacement DR reaches a predetermined value, the driving member 31, the spring material 51, and the torque are switched. The driving of the rotary mass 23 via the transmission unit 32 is repeatedly performed.

  As described above, according to the rotary mass damper 10 </ b> B of the present embodiment, the driving member 31 presses the torque transmission unit 32 via the spring material 51, so that the driving member 31 contacts the torque transmission unit 32. Compared with, it is possible to reduce the impact load and load acting on both members 31, 32, and to suppress damage and wear thereof.

  Further, as the movement amount Xr of the drive member 31 increases, the compression amount of the spring material 51 increases, and accordingly, the pressing force of the torque transmission unit 32 and the transmission torque Tr to the rotary mass 23 increase. As a result, as the relative displacement DR increases, the rotational inertial mass effect can be increased. Therefore, it is possible to more appropriately suppress the relative displacement during an earthquake according to the actual relative displacement DR. it can.

  Moreover, the sliding material 52 interposed between the drive member 31 and the spring material 51 can reduce the impact load and load which act on the drive member 31 and the spring material 51, and can further suppress those damage and wear.

  The slope of the broken line in FIG. 12 represents the rate of increase / decrease in the transmission torque Tr with respect to the compression amount of the spring material 51 (the amount of movement of the drive member 31). It can be changed by setting the friction coefficient.

  Next, a rotary mass damper 10C according to a third embodiment of the present invention will be described with reference to FIGS. As shown in the figure, this rotary mass damper 10C is a viscous body 61 for obtaining a viscous damping effect between the inner cylinder 21 and the rotary mass 23 with respect to the rotary mass damper 10B of the second embodiment shown in FIG. Is added.

  In the present embodiment, the central portion of the inner cylinder 21 is a large-diameter enlarged portion 21 a having a large outer diameter, and a pair of ring-shaped sealing materials 62, 62 is provided between the large-diameter portion 21 a and the rotating mass 23. Is provided. The space between the enlarged diameter portion 21a and the rotating mass 23 sealed with the sealing materials 62, 62 is filled with a viscous body 61 made of silicon oil or the like.

  Further, the length of the spring material 51 is larger than that of the second embodiment, and accordingly, the gap between the drive member 31 and each sliding material 52 when the drive member 31 is in the neutral position is increased. The size is a smaller predetermined amount G3.

  When the rotary mass damper 10C having the above configuration is modeled, it is expressed as shown in FIG. That is, in the rotary mass damper 10C, the viscous element composed of the inertia connecting element composed of the rotational mass 23 and the viscous body 61 is connected to the elastic element composed of the screw shaft 22a and the like via the torque transmission mechanism 24 composed of the drive member 31 and the spring material 51. The elements are connected in parallel.

  Therefore, according to the rotary mass damper 10C, when the relative displacement DR reaches a predetermined value corresponding to the predetermined amount G3, the drive member 31 comes into contact with the spring material 51, and the rotary mass damper 24 As 23 is driven, in addition to the rotational inertial mass effect by the rotary mass 23, the viscous damping effect by the viscous body 61 can be obtained, and the effect of suppressing relative displacement can be further enhanced.

  The viscous damping effect of the viscous body 61 increases in proportion to the rotational speed of the rotary mass 23. The viscous damping effect can be changed by setting the density and viscosity of the viscous body 61, the volume between the inner cylinder 21 filled with the viscous body 61 and the rotary mass 23, and the like.

  Next, a rotary mass damper 10D according to a fourth embodiment of the present invention will be described with reference to FIGS. 15 and 16. As shown in the figure, the rotary mass damper 10D is compared with the rotary mass damper 10B of the second embodiment shown in FIG. And a predetermined compressive load (hereinafter referred to as “preload”) Pc is applied to both spring members 51 and 51 in advance. In the present embodiment, as in the example shown in FIG. 7, the drive member 31 is screwed into the ball nut 22 c and is splined to the rotary mass 23.

  Therefore, according to the rotary mass damper 10D, when the relative displacement DR is 0 and the driving member 31 is in the neutral position shown in FIG. 15, the pressing force of each torque transmitting portion 32 is equal to the preload Pc. From this state, when the drive member 31 moves in the axial direction along with the occurrence of the relative displacement DR, one of the spring members 51 is compressed by the drive member 31 and, at the same time, the compression load of the spring member 51 increases. When the other spring material 51 extends following the drive member 31, the compression load of the spring material 51 decreases.

  As a result, the increase in the compressive load of one spring member 51 and the decrease in the compressive load of the other spring member 51 are offset, so that the pressing force of one torque transmitting portion 32 is substantially equal to the preload Pc. Accordingly, the torque Tr transmitted to the rotary mass 23 and the rotary inertia mass effect are kept at a relatively small and substantially constant value (points O4 to a4 in FIG. 16).

  When the relative displacement DR further increases and reaches a predetermined value, the moving amount Xr of the driving member 31 reaches the predetermined amount G4, and the extension of the other spring material 51 reaches the limit, so that the driving member 31 can move the other spring. After leaving the material 51 (point a4), the one spring material 51 is continuously compressed. For this reason, as the amount of compression of one spring material 51 increases, the pressing force of the torque transmitting portion 32 increases, so that the transmission torque Tr to the rotating mass 23 and the rotating inertial mass effect increase (points). a4 to point b4).

  The subsequent operation is basically the same as in the case of the rotary mass damper 10B of the second embodiment, and the sign of the transmission torque Tr is reversed (points b4 to c4) as the direction of the relative displacement DR is reversed. At the same time, as the drive member 31 moves in the opposite direction, the amount of compression of the spring material 51 and the transmission torque Tr decrease (points c4 to d4). When the relative displacement DR decreases to a predetermined value, the drive member 31 comes into contact with the other spring material 51 again (point d4). Thereafter, when the relative displacement DR becomes 0, the drive member 31 Returns to the neutral position. The operation when the relative displacement DR increases in the opposite direction from this state is only described in which the moving direction of the drive member 31 is opposite to that described above, and the description thereof is omitted.

  As described above, according to the rotary mass damper 10D of the present embodiment, in a predetermined range where the relative displacement DR is small, an approximately constant and relatively small rotational inertial mass effect is obtained, and the relative displacement DR exceeds the predetermined range. After that, the rotational inertial mass effect can be increased as the relative displacement DR increases. Therefore, as in the second embodiment, it is possible to appropriately suppress the relative displacement during an earthquake according to the actual relative displacement DR.

  Next, a rotary mass damper 10E according to a fifth embodiment of the present invention will be described with reference to FIG. As shown in the figure, the rotary mass damper 10E is obtained by adding a second rotary mass 123 and a second torque transmission mechanism 124 to the rotary mass damper 10A of the first embodiment shown in FIG.

  Similar to the rotary mass 23, the second rotary mass 123 is made of a material having a large specific gravity, such as iron, and is formed in a cylindrical shape. The second rotating mass 123 has a larger diameter than the rotating mass 23, is coaxially disposed on the outer side thereof, and is rotatably supported by the rotating mass 23 via a bearing 128.

  The second torque transmission mechanism 124 drives the second rotation mass 123 by transmitting torque from the rotation mass 23 to the second rotation mass 123, and its basic configuration is the same as that of the torque transmission mechanism 24. . Specifically, the second torque transmission mechanism 124 is disposed between the rotary mass 23 and the second rotary mass 123, and a spline hole and a male screw (both not shown) are formed on the inner peripheral surface and the outer peripheral surface, respectively. The ring-shaped second drive member 131 and a pair of ring-shaped second torque transmission portions 132, 132 provided integrally on the inner peripheral surface of the second rotating mass 123 and disposed on both sides of the second drive member 131. Etc.

  The spline hole of the second drive member 131 is fitted to the spline teeth 23 c formed integrally with the outer peripheral surface of the rotary mass 23, and the male screw of the second drive member 131 is formed on the inner peripheral surface of the second rotary mass 123. The female screw 123a is screwed. In the neutral state shown in FIG. 17, the size of the gap between the drive member 31 and each torque transmission unit 32 is set to the first predetermined amount G5, and the second drive member 131 and each second torque transmission unit 132 The size of the gap is set to the second predetermined amount G6.

  According to the above configuration, in addition to the operation of the rotary mass damper 10A described above, the rotary inertia mass effect by the second rotary mass 123 can be obtained. That is, when the relative displacement DR reaches the first predetermined value corresponding to the first predetermined amount G5, the driving member 31 comes into contact with the torque transmitting portion 32, so that torque is applied from the ball nut 22c to the rotary mass 23. The rotational inertia mass effect of the rotary mass 23 is obtained.

  Further, when the rotation mass 23 rotates, the second drive member 131 moves in the axial direction, and when the movement amount reaches the second predetermined amount G6, that is, the rotation amount of the rotation mass 23 reaches the predetermined amount. When this occurs, the second drive member 131 comes into contact with the second torque transmission portion 132. As a result, torque is transmitted from the rotating mass 23 to the second rotating mass 123 and the second rotating mass 123 is driven, whereby the rotational inertial mass effect by the second rotating mass 123 is exhibited.

  As described above, when the relative displacement DR in the same direction continues after obtaining the rotary inertia mass effect of the rotary mass 23, the second rotary mass 123 is driven by the second torque transmission mechanism 124, and the second rotation The rotational inertia mass effect of the mass 123 is added. As a result, the rotational inertial mass effect can be increased in two stages according to the actual occurrence state of the relative displacement DR, and the relative displacement can be appropriately suppressed particularly during a huge earthquake.

  In addition, this invention can be implemented in a various aspect, without being limited to the 1st-5th embodiment and modification which were demonstrated until now. For example, in the second, third, and fifth embodiments, the drive member 31 is splined to the ball nut 22c and screwed to the rotating mass 23. In the fourth embodiment, the driving member 31 is splined to the rotating mass 23. In this embodiment, the relationship may be reversed in each embodiment.

  Further, the viscous body 61 applied to the third embodiment may be similarly used between the ball nut 22c and the rotating mass 23 of the other embodiments, and further, the rotating mass 23 and the second rotation of the fifth embodiment. It may be used between the masses 123. Thereby, the viscous damping effect of the viscous body 61 is added to the rotational inertial mass effect of the rotary masses 23 and 123, so that the effect of suppressing the relative displacement can be further enhanced.

  Furthermore, in the fifth embodiment, the torque transmission mechanism 24 is disposed between the ball nut 22 c and the rotating mass 23, and the second torque transmitting mechanism 124 is disposed between the rotating mass 23 and the second rotating mass 123. Of these, the torque transmission mechanism 24 may be omitted. In this case, the ball nut 22c and the rotating mass 23 are directly connected, so that the rotating mass 23 is driven from the initial stage of the generation of the relative displacement DR, and the rotary inertia mass effect is exhibited.

  Moreover, the lock mechanism 41 shown as a modification is an illustration to the last, and as long as it can lock the drive member 31 in the state which contact | abutted to the torque transmission part 32, it is possible to employ | adopt other arbitrary structures. is there.

  Furthermore, although the seismic isolation bearing 3 is of a rolling type in the embodiment, it is needless to say that other types such as a sliding type may be used. In addition, the embodiment is an example in which the structure is a building 2, but the seismic isolation damper according to the present invention can be applied to other structures such as a steel tower and a bridge. It may be applied to the middle floor seismic isolation instead. In addition, it is possible to appropriately change the detailed configuration within the scope of the gist of the present invention.

1 foundation (ground)
2 Building (structure)
3 Seismic isolation bearing 10 Rotating mass damper (Seismic isolation damper)
21 Inner cylinder (cylinder)
22 Ball screw 22a Screw shaft 22b Ball 22c Ball nut 23 Rotating mass 24 Torque transmission mechanism 31 Drive member 32 Torque transmission portion 41 Lock mechanism 51 Spring material 52 Sliding material 61 Viscous body 123 Second rotation mass 124 Second torque transmission mechanism 131 First 2 Driving member 132 Second torque transmission portion Xr Movement amount of driving member G1 Predetermined amount

Claims (7)

A seismic isolation damper provided between the ground and the structure together with a seismic isolation bearing, for suppressing relative displacement between the ground and the structure during an earthquake,
A cylinder having one end connected to one of the ground and the structure;
One end is connected to the other of the ground and the structure, the other end is a screw shaft that is movably fitted to the other end of the cylindrical body,
Coaxially disposed outside the screw shaft and screwed into the screw shaft via a number of freely rolling balls, and as the screw shaft moves in the axial direction with respect to the cylindrical body. A rotating ball nut,
A rotatable cylindrical rotary mass arranged coaxially on the outside of the cylindrical body and the ball nut;
A pair of ring-shaped torque transmitting portions that are integrally provided on the inner peripheral surface of the rotating mass and are spaced apart from each other in the axial direction;
Between the ball nut and the rotating mass and between the pair of torque transmitting portions, the pair of torque transmitting portions are disposed at a predetermined interval and rotate with respect to one of the ball nut and the rotating mass. A ring-shaped drive member that is impossible and movable in the axial direction and is screwed to the other,
The drive member moves in the axial direction along with the rotation of the ball nut, thereby pressing the torque of the ball nut via the one torque transmission unit while pressing one of the pair of torque transmission units. The seismic isolation damper is configured to rotate the rotating mass by transmitting to the rotating mass. The drive member is configured to contact the torque transmission unit when the amount of movement in the axial direction reaches a predetermined amount,
The seismic isolation damper according to claim 1, further comprising a lock mechanism that locks the drive member to the torque transmission unit when the drive member abuts on the torque transmission unit.   And a pair of spring members disposed between the drive member and the pair of torque transmission parts, and the drive member moves in the axial direction as the drive member moves through the spring material to the torque transmission part. The seismic isolation damper according to claim 1, wherein the seismic isolation damper is configured so as to press the   The pair of spring members are in contact with the drive member and the pair of torque transmission portions in a state where the drive member is in a neutral position, and a predetermined compressive load is applied in advance. 3. A seismic isolation damper according to 3.   The seismic isolation damper according to claim 3, further comprising a sliding member interposed between the driving member and the pair of spring members.   The seismic isolation damper according to any one of claims 1 to 5, further comprising a viscous body filled between the rotating mass and the cylindrical body. A rotatable second cylindrical rotating mass disposed coaxially outside the rotating mass;
A pair of ring-shaped second torque transmitting portions that are integrally provided on the inner peripheral surface of the second rotating mass and are spaced apart from each other in the axial direction;
Between the rotating mass and the second rotating mass and between the pair of second torque transmitting portions, a predetermined interval is provided, and the rotating mass and the second rotating mass cannot rotate with respect to one of the rotating mass and the second rotating mass. And a ring-shaped second drive member that is movably provided in the axial direction and screwed to the other,
The second drive member moves in the axial direction as the rotary mass rotates, thereby pressing the torque of the rotary mass while pressing one of the pair of second torque transmission portions. 7. The structure according to claim 1, wherein the second rotating mass is configured to rotate by being transmitted to the second rotating mass via the second torque transmitting unit. Seismic isolation damper.

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