JP6629079B2 - Mass damper - Google Patents

Description

  The present invention relates to a mass damper for suppressing vibration of a structure.

  Conventionally, as this type of mass damper, for example, a mass damper disclosed in Patent Document 1 is known. The mass damper is provided coaxially at one end of the main body with a cylindrical main body defining a single fluid chamber, a working fluid filled in the fluid chamber, and rotatably supports the main body. And a ball screw coaxially provided at the other end of the main body. The main body is also used as a rotating mass. Further, a single piston is provided integrally with the shaft member, and the piston is provided in the fluid chamber so as to be slidable in the axial direction of the main body, and the fluid chamber is provided with two fluids. It is divided into rooms. The nut of the above ball screw is attached to the other end of the main body, and the screw shaft of the ball screw is screwed to the nut via a number of balls and is movable in the axial direction with respect to the main body. It is.

  In the conventional mass damper having the above-described configuration, the pressure of the working fluid allows the main body, the shaft member, and the piston to move the main body from the shaft member in the axial direction while allowing the relative rotation between the shaft member and the main body. Acts not to move in the radial direction, whereby the main body is rotatably held with respect to the shaft member. Thus, the working fluid and the piston function as a so-called fluid bearing. Further, when the screw shaft is moved in the axial direction with respect to the main body by an external force, the movement of the screw shaft is transmitted to the main body in a state where the movement is converted into a rotational motion by the ball screw, thereby rotating the main body. As a result, a rotational inertial mass effect by the main body is obtained.

JP-A-2015-83865 (FIG. 5 and the like)

  This type of mass damper is mainly used to suppress the vibration of a structure such as a building. When the structure is vibrated, the displacement of the structure is transmitted, and a relatively large axial Load acts. On the other hand, in the above-mentioned conventional mass damper, since only one set of pistons and a fluid chamber as a fluid bearing are provided, the axial load cannot be sufficiently borne, and as a result, the rotational inertia of the main body portion is reduced. The mass effect may not be properly obtained.

  The present invention has been made in order to solve the above-described problems, and provides a mass damper that can sufficiently bear an input axial load, thereby appropriately obtaining a rotational inertial mass effect of a main body. The purpose is to provide.

  In order to achieve the above object, an invention according to claim 1 is a mass damper provided between a first part and a second part in a system including a structure, and configured to suppress vibration of the structure. A cylindrical main body, a rotating mass provided integrally with the main body, and a first portion connected to the first portion and extending in the axial direction of the main portion; A screw shaft movably and coaxially provided, a nut screwed to the screw shaft via a ball, and a nut attached to one portion of the main body, and connected to the second portion to extend in the axial direction And a support shaft provided coaxially with the other portion in the axial direction of the main body portion to rotatably support the main body portion, and a state in which one of the main body portion and the support shaft is spaced apart from each other in the axial direction. Are provided integrally to define a pair of fluid chambers in the main body. The first wall, the second wall, and the third wall, the working fluid filled in the pair of fluid chambers, and the other of the main body and the support shaft are provided integrally with each other, and each of the pair of fluid chambers has two fluids. A pair of pressure-receiving sections, each of which is partitioned in the axial direction into the chamber and held by the pressure of the working fluid in the two fluid chambers so as not to move in the axial direction with respect to the pair of fluid chambers. It is characterized by being held rotatably with respect to the support shaft by the pressure of the working fluid.

  According to this configuration, the rotating mass is provided integrally with the cylindrical main body, and the screw shaft is provided so as to be movable in the axial direction and coaxially at one portion in the axial direction of the main body. Has been. The screw shaft is connected to the first portion and extends in the axial direction. In addition, a nut attached to one part of the main body is screwed to the screw shaft via a ball. A support shaft for rotatably supporting the main body is provided coaxially at the other portion of the main body in the axial direction, and the support shaft is connected to the second portion and extends in the axial direction. ing. First to third wall portions are integrally provided on one of the main body portion and the support shaft with a space therebetween in the axial direction. The first to third walls define a pair of fluid chambers in the main body, and the pair of fluid chambers are filled with a working fluid. Further, a pair of pressure receiving portions are integrally provided on the other of the main body portion and the support shaft in a state of being spaced apart from each other in the axial direction. The pair of pressure receiving portions divides the pair of fluid chambers into two fluid chambers in the axial direction, and does not move in the axial direction with respect to the pair of fluid chambers due to the pressure of the working fluid in the two fluid chambers. Respectively.

  In the mass damper having the above-described configuration, the relative displacement between the first portion and the second portion generated due to the vibration of the structure is transmitted to the support shaft and the screw shaft, and further converted to rotational motion via the nut. It is transmitted to the main body in the state of being performed. Accordingly, the main body and the rotating mass rotate together with respect to the support shaft, and a rotational inertial mass effect by the rotating mass is obtained, thereby suppressing vibration of the structure.

  In this case, as described above, the first to third walls defining the pair of fluid chambers filled with the working fluid in the main body are provided on one of the main body and the support shaft, and the pair of fluid chambers are provided. Are divided into two fluid chambers in the axial direction, respectively. A pair of pressure receiving portions is provided on the other of the main body and the support shaft. With the above configuration, a part of the support shaft is housed in the pair of fluid chambers, and the pressure of the working fluid filled in the pair of fluid chambers is pressed against the support shaft toward the center of the entire outer peripheral surface thereof. At the same time, it acts on the main body so as to radially press the entire inner peripheral surface thereof. In addition, even if an external force in the direction of moving the pair of pressure receiving portions in the axial direction with respect to the pair of fluid chambers acts on both of the pair of pressure receiving portions along with the vibration of the structure, the pair of pressure receiving portions will Due to the pressure of the working fluid in the chambers, they are held so as not to move in the axial direction with respect to the pair of fluid chambers.

  As described above, during the vibration of the structure, the pressure of the working fluid in the fluid chamber causes the main body to rotate relative to the main body, the support shaft, and the pair of pressure receiving portions while allowing the relative rotation between the support shaft and the main body. It acts so as not to move from the support shaft in the axial direction or the direction perpendicular to the axial direction, whereby the main body is rotatably held with respect to the support shaft. As described above, the working fluid and the pair of pressure receiving portions function as a so-called fluid bearing. In this case, the mass damper is different from the above-described conventional mass damper in that the fluid bearing is not one set of fluid chamber and pressure receiving portion (piston), but two sets of fluid chamber and pressure receiving portion comprising a pair of fluid chamber and pressure receiving portion. Is provided, and the pressure (reaction force) of the working fluid can be received by the pair of pressure receiving portions, so that the axial load input to the mass damper can be sufficiently borne, thereby appropriately controlling the rotational inertial mass effect of the main body. Can be obtained.

  According to a second aspect of the present invention, in the mass damper according to the first aspect, an external force in a direction of moving the pair of pressure receiving portions in the axial direction with respect to the pair of fluid chambers is input to the pair of pressure receiving portions. In each of the pair of fluid chambers, the pressure of the working fluid in one of the two fluid chambers is released to the other of the two fluid chambers immediately before the pressure of the working fluid in one of the two fluid chambers becomes excessive. And a relief mechanism for allowing the pressure receiving portion to move.

  According to this configuration, the external force in the direction of moving the pair of pressure receiving portions in the axial direction with respect to the pair of fluid chambers is input to each of the two, so that each of the pair of fluid chambers is partitioned by the respective pressure receiving portion. Immediately before the pressure of the working fluid in one of the two fluid chambers becomes excessive, the pressure of the working fluid in one of the two fluid chambers is increased by the relief mechanism in each of the pair of fluid chambers. Escaped to the other. This allows the pair of pressure receiving parts to move in the axial direction with respect to the pair of fluid chambers, respectively, so that the load acting on the mass damper in the axial direction (hereinafter referred to as “axial load”) becomes excessive. Can be prevented.

  According to a third aspect of the present invention, in the mass damper according to the first or second aspect, the main body and the rotary mass are formed of a common member.

  According to this configuration, since the main body and the rotating mass are formed of a common member, the number of parts can be reduced accordingly, and the manufacturing cost can be reduced, and the mass damper can be simply configured. can do.

FIG. 2 is a cross-sectional view illustrating the mass damper according to the first embodiment of the present invention. FIG. 2A is an enlarged sectional view showing first and second relief valves for the first communication passage in FIG. 1, and FIG. 2B is a cross-sectional view showing the first and second relief valves for the second communication passage in FIG. It is sectional drawing which expands and shows. FIG. 2 is a diagram schematically illustrating the mass damper of FIG. 1 together with a part of a building to which the mass damper is applied. FIG. 6 is a sectional view illustrating a mass damper according to a second embodiment of the present invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a mass damper 1 according to a first embodiment of the present invention. Hereinafter, for convenience, the left and right sides of FIG. 1 will be described as “left” and “right”, respectively. As shown in FIG. 1, the mass damper 1 is provided on a left side of the main body 2, a cylindrical main body 2 extending in the left-right direction (axial direction), a rotating mass provided integrally with the main body 2, A support shaft 3 for rotatably supporting the main body 2, a ball screw 4 provided on a right portion of the main body 2, a cylindrical first pressure receiving portion 5 provided integrally with the support shaft 3, and a 2 includes a pressure receiving unit 6 and a relief mechanism 11.

  The main body 2 is made of a material having a relatively large specific gravity, for example, iron, and has a cylindrical peripheral wall 2a and right and left donut-shaped left and right side walls provided coaxially and integrally at left and right ends of the peripheral wall 2a. 2b and 2c, and a donut plate-shaped first partition wall 2d and a second partition wall 2e provided coaxially and integrally from the left side on the left side of the peripheral wall 2a. The mass is composed of members common to each other. That is, the main body 2 is also used as a rotating mass. The left side wall 2b, the first and second partition walls 2d and 2e, and the right side wall 2c are formed with insertion holes 2f, 2g, 2h and 2i penetrating in the left-right direction, respectively. , And coaxially with the peripheral wall 2a. In the main body 2, a pair of left and right fluid chambers is defined by a peripheral wall 2a, a left side wall 2b, and first and second partition walls 2d and 2e. HF is densely packed. The working fluid HF is made of, for example, silicone oil, and the pressure of the working fluid HF acts on the main body 2 so as to radially press the entire inner peripheral surface thereof.

  The support shaft 3 is inserted into the insertion holes 2f to 2h of the main body 2 via a seal, extends in the left-right direction, and rotatably supports the main body 2. The support shaft 3 is partially accommodated coaxially in the left part of the main body 2, and protrudes leftward from the main body 2. The first and second pressure receiving portions 5 and 6 are integrally provided coaxially at a central portion of the support shaft 3 in the axial direction.

  The first and second pressure receiving portions 5 and 6 are provided with seals on respective outer peripheral surfaces thereof, and are housed in the above-mentioned pair of left and right fluid chambers together with the central portion of the support shaft 3, respectively. The outer peripheral surface is in contact with the inner peripheral surface of the peripheral wall 2a via a seal. As described above, since the central portion of the support shaft 3 is housed in the left and right fluid chambers, the pressure of the working fluid HF in the left and right fluid chambers presses the entire outer peripheral surface of the support shaft 3 toward the center. Act on. The left fluid chamber of the pair of fluid chambers is partitioned by the first pressure receiving portion 5 into a first fluid chamber 2j on the left and a second fluid chamber 2k on the right, and the fluid chamber on the right is The two pressure receiving sections 6 partition the first fluid chamber 2l on the left and the second fluid chamber 2m on the right. The first and second pressure receiving portions 5 and 6 are held by the pressure of the working fluid HF in the corresponding first and second fluid chambers 2j to 2m so as not to move in the left and right directions with respect to the left and right fluid chambers. I have.

  The ball screw 4 has a screw shaft 4a and a nut 4c screwed to the screw shaft 4a via a number of balls 4b. The screw shaft 4a is inserted into the insertion hole 2i of the right side wall 2c via a sliding material, and extends in the left-right direction. The sliding member is made of a material having high lubricity, for example, a fluororesin. The screw shaft 4 a is partially accommodated coaxially in the right part of the main body 2 so as to be movable in the left-right direction and protrudes rightward from the main body 2. The nut 4c is coaxially attached to the right surface of the right side wall 2c, and a central screw hole thereof communicates with the insertion hole 2i.

  A first fitting FL1 and a second fitting FL2 are attached to the left end of the support shaft 3 and the right end of the screw shaft 4a via a universal joint, respectively. These universal joints have such a frictional force that the support shaft 3 and the screw shaft 4a do not rotate with respect to the first and second fittings FL1 and FL2, respectively, due to the torque generated by the reaction force of the rotating main body 2 as described later. have.

  In the mass damper 1, the pressure of the working fluid HF in the first and second fluid chambers 2 j to 2 m increases the pressure between the support shaft 3 and the main body 2 with respect to the support shaft 3 and the first and second pressure receiving portions 5 and 6. Acts so as not to move the main body 2 from the support shaft 3 in the axial direction (left-right direction) or radial direction while allowing relative rotation, whereby the main body 2 is held rotatably with respect to the support shaft 3. Is done. Thus, the working fluid HF and the first and second pressure receiving portions 5 and 6 function as a so-called fluid bearing.

  The pressure of the working fluid HF in each of the first and second fluid chambers 2j to 2m is excessive in order to prevent a load acting on the mass damper 1 in the axial direction (hereinafter referred to as “axial load”) from becoming excessive. Immediately before, the pressure of the working fluid HF in one of the first and second fluid chambers 2j, 2k (2l, 2m) is released to the other, so that the first and second pressure receiving portions 5, 6 become a pair of fluid chambers. , Respectively. Specifically, the relief mechanism 11 includes a first communication path 12 and a second communication path 13 connected to the main body 2, a first relief valve 14 and a second relief valve 15 for the first communication path 12, It has a first relief valve 16 and a second relief valve 17 for the second communication passage 13.

  The first communication passage 12 is configured to bypass the first pressure receiving portion 5 and communicate with the first fluid chamber 2j and the second fluid chamber 2k, and the second communication passage 13 includes the second pressure receiving portion 6 And is connected to the first fluid chamber 21 and the second fluid chamber 2m. The cross-sectional area of the first and second communication passages 12 and 13 is set to a value smaller than the cross-sectional area of the main body 2. Further, the first and second communication passages 12 and 13 are also densely filled with the working fluid HF.

  As shown in FIG. 1 and FIG. 2A, the first relief valve 14 and the second relief valve 15 for the first communication passage 12 are provided at the center of the first communication passage 12. As shown in FIG. 2A, a central portion of the first communication path 12 is a first branch path 12a and a second branch path 12b that are branched into two, and the first and second branch paths are formed. First and second relief valves 14 and 15 are provided in 12a and 12b, respectively. In FIG. 1, illustration of the first and second branch passages 12a and 12b is omitted for convenience.

  The first relief valve 14 includes a valve body 14a, a spring 14b for urging the valve body 14a in a valve closing direction, and the like. The pressure of the working fluid HF in the first fluid chamber 2j is higher than a predetermined upper limit value. Is smaller, the first branch passage 12a is closed, and when the upper limit is reached, the first branch passage 12a is opened. When the first relief passage 14 opens the first branch passage 12 a, the first and second fluid chambers 2 j and 2 k communicate with each other via the first communication passage 12.

  Like the first relief valve 14, the second relief valve 15 includes a valve body 15a, a spring 15b for urging the valve body 15a in the valve closing direction, and the like, and the working fluid HF in the second fluid chamber 2k. When the pressure is smaller than the predetermined upper limit, the second branch passage 12b is closed, and when the pressure reaches the upper limit, the second branch passage 12b is opened. When the second branch passage 12 b is opened by the second relief valve 15, the second and first fluid chambers 2 k and 2 j communicate with each other via the first communication passage 12.

  As shown in FIG. 1 and FIG. 2B, the first relief valve 16 and the second relief valve 17 for the second communication passage 13 are provided at the center of the second communication passage 13. As shown in FIG. 2B, the central portion of the second communication passage 13 is, like the first communication passage 12, a first branch passage 13 a and a second branch passage 13 b that are branched into two. First and second relief valves 16 and 17 are provided in the first and second branch passages 13a and 13b, respectively. In FIG. 1, illustration of the first and second branch passages 13a and 13b is omitted for convenience.

  The first relief valve 16 includes a valve body 16a, a spring 16b for urging the valve body 16a in the valve closing direction, and the like, and the pressure of the working fluid HF in the first fluid chamber 21 is higher than the upper limit value. When it is smaller, the first branch passage 13a is closed, and when it reaches the upper limit, the first branch passage 13a is opened. The opening of the first branch passage 13 a by the first relief valve 16 allows the first and second fluid chambers 21 and 2 m to communicate with each other via the second communication passage 13.

  Like the first relief valve 16, the second relief valve 17 includes a valve element 17a, a spring 17b for urging the valve element 17a in the valve closing direction, and the like, and the working fluid HF in the second fluid chamber 2m. When the pressure is smaller than the upper limit, the second branch passage 13b is closed, and when the pressure reaches the upper limit, the second branch passage 13b is opened. When the second relief passage 17 opens the second branch passage 13 b, the second and first fluid chambers 2 m and 21 communicate with each other via the second communication passage 13.

  As shown in FIG. 3, the mass damper 1 having the above-described configuration has a V-shaped joint between the upper beam BU and the left column PL of the building B and the junction of the upper beam BU and the right column PR of the building B. In addition to being connected via the brace material BR, it is connected via a connecting member EN to the joint between the lower beam BD of the building B and the right column PR. In this case, the first attachment FL1 is attached to the lower end of the brace material BR, and the second attachment FL2 is attached to the connecting member EN, and the mass damper 1 extends in the left-right direction. The brace material BR and the connecting member EN are made of, for example, H-shaped steel. When the building B is not vibrating, the first and second pressure receiving portions 5 and 6 are at the neutral position shown in FIG. In FIG. 3, some components such as the first and second communication paths 12 and 13 are not shown for convenience.

  When a relative displacement occurs between the upper and lower beams BU and BD due to the vibration of the building B, and thereby a tensile force acts on the mass damper 1, the tensile force causes the support shaft 3 and the screw shaft 4a to move to the main body. It acts to move left and right with respect to 2, respectively. In this case, the pulling force acts on the first and second pressure receiving portions 5 and 6 integrated with the support shaft 3 so as to move the body to the left with respect to the main body portion 2, and accordingly, the first fluid chamber 2 j , 2l, the working fluid HF is pressed by the first and second pressure receiving portions 5, 6, respectively, so that the pressure increases. When the pressure of the working fluid HF in the first fluid chambers 2j and 21 does not reach the upper limit, the first branch passages 12a and 13a of the first and second communication passages 12 and 13 are connected to the first relief valves 14 and 16 respectively. , Respectively. In this case, the working fluid HF in the second fluid chambers 2k and 2m is not pressed by the first and second pressure receiving portions 5 and 6, respectively, and the pressure does not reach the upper limit value. The second branch passages 12b and 13b of the passages 12 and 13 are also kept closed by the second relief valves 15 and 17, respectively.

  As described above, when the pulling force acts on the mass damper 1 and the pressure of the working fluid HF in the first fluid chambers 2j and 21 does not reach the upper limit, the working fluid HF in the first fluid chambers 2j and 21 becomes the The main body 2, the support shaft 3, and the first and second pressure receiving portions 5 and 6 do not flow to the two fluid chambers 2 k and 2 m, and the pressure of the working fluid HF in the first and second fluid chambers 2 j to 2 m. As a result, they are held so as not to move relative to each other in the left-right direction. Further, the screw shaft 4a moves rightward due to the above-described tensile force, and accordingly, the nut 4c screwed to the screw shaft 4a moves together with the main body 2 with respect to the support shaft 3 and the screw shaft 4a. Rotate. As described above, when the tensile force acts on the mass damper 1 with the vibration of the building B, the relative displacement between the upper and lower beams BU and BD is determined via the support shaft 3, the screw shaft 4a, and the nut 4c. The rotational motion is transmitted to the main body 2 in a converted state, whereby the main body 2 serving as a rotating mass rotates.

  When the pressure of the working fluid HF in the first fluid chambers 2j and 2l reaches the upper limit value when the tensile force acts on the mass damper 1, the first branch passages 12a and 13a are moved by the first relief valves 14 and 16 by the first relief valves 14 and 16. Each of the working fluids HF in the first fluid chambers 2j and 2l is opened, and flows into the second fluid chambers 2k and 2m through the first and second communication passages 12 and 13, respectively. As a result, the pressure of the working fluid HF in the first fluid chambers 2j and 21 is released to the second fluid chambers 2k and 2m, so that the first and second pressure receiving portions 5 and 6 with respect to the pair of fluid chambers move to the left. Each movement is allowed.

  On the other hand, when a compressive force acts on the mass damper 1, the compressive force applies the support shaft 3, the first and second pressure receiving portions 5 and 6 to the right of the main body 2, and the screw shaft 4 a to the main body 2. To the left. Accordingly, the working fluid HF in the second fluid chambers 2k and 2m is pressed by the first and second pressure receiving portions 5 and 6, respectively, so that the pressure increases. When the pressure of the working fluid HF in the second fluid chambers 2k and 2m has not reached the upper limit, the second branch passages 12b and 13b of the first and second communication passages 12 and 13 are moved by the second relief valves 15 and 17. Each is kept in a closed state. In this case, the working fluid HF in the first fluid chambers 2j and 2l is not pressed by the first and second pressure receiving portions 5 and 6, respectively, so that the pressure does not reach the upper limit value. The first branch passages 12a and 13a of the passages 12 and 13 are also kept closed by the first relief valves 14 and 16, respectively.

  As described above, when the pressure of the working fluid HF in the second fluid chambers 2k and 2m does not reach the upper limit value when the compressive force acts on the mass damper 1, the working fluid HF in the second fluid chambers 2k and 2m The main body 2, the support shaft 3, and the first and second pressure receiving parts 5 and 6 do not flow to the one fluid chamber 2 j and 21, and the pressure of the working fluid HF in the first and second fluid chambers 2 j to 2 m As a result, they are held so as not to move relative to each other in the left-right direction. The screw shaft 4a moves leftward due to the above-described compression force, and accordingly, the nut 4c rotates together with the main body 2. As described above, even when a compressive force acts on the mass damper 1 due to the vibration of the building B, the relative displacement between the upper and lower beams BU and BD rotates through the support shaft 3, the screw shaft 4a, and the nut 4c. The main body 2 is rotated by being transmitted to the main body 2 in a state converted into motion.

  Further, when the compressive force acts on the mass damper 1 and the pressure of the working fluid HF in the second fluid chambers 2 k and 2 m reaches the upper limit, the second branch passages 12 b and 13 b are moved by the second relief valves 15 and 17. Each of the working fluids HF in the second fluid chambers 2k and 2m is opened, and flows to the first fluid chambers 2j and 21 via the first and second communication paths 12 and 13, respectively. As a result, the pressure of the working fluid HF in the second fluid chambers 2k and 2m is released to the first fluid chambers 2j and 21 so that the first and second pressure receiving portions 5 and 6 with respect to the pair of fluid chambers move to the right. Each movement is allowed.

  As described above, according to the first embodiment, the cylindrical main body 2 is also used as a rotating mass. A support shaft 3 for rotatably supporting the main body 2 is provided on the left side of the main body 2 in a coaxial manner. The support shaft 3 is connected to the upper beam BU of the building B and has an axis. Extending in the direction. On the right side of the main body 2, a screw shaft 4a is provided coaxially so as to be movable in the axial direction, and the screw shaft 4a is connected to the lower beam BD of the building B and extends in the axial direction. A nut 4c attached to the right end of the main body 2 is screwed to the screw shaft 4a via a ball 4b.

  The main body 2 is integrally provided with a left side wall 2b and first and second partition walls 2d and 2e with a space therebetween in the axial direction. The left side wall 2b, the first and second partition walls 2d, 2e define a pair of left and right fluid chambers in the main body 2, and these pair of fluid chambers are filled with a working fluid HF. . The support shaft 3 is provided with first and second pressure receiving portions 5 and 6 integrally. The first and second pressure receiving portions 5 and 6 axially partition a pair of left and right fluid chambers into first and second fluid chambers 2j and 2k (2l and 2m), respectively. Due to the pressure of the working fluid HF in the chambers 2j to 2m, the left and right fluid chambers are held so as not to move in the axial direction.

  In the mass damper 1, the relative displacement between the upper and lower beams BU and BD generated due to the vibration of the building B is transmitted to the support shaft 3 and the screw shaft 4a, and further converted to a rotational motion via the nut 4c. It is transmitted to the main body 2 in the state of being turned. As a result, the main body 2 rotates with respect to the support shaft 3, and a rotational inertia mass effect is obtained by the main body 2 also serving as a rotating mass, thereby suppressing vibration of the building B.

  In this case, as described above, the pressure of the working fluid HF filled in the left and right fluid chambers acts on the main body 2 so as to radially press the entire inner peripheral surface thereof, and acts on the support shaft 3. This acts to press the entire outer peripheral surface toward the center. Further, even if an external force in the direction of moving the first and second pressure receiving portions 5 and 6 in the axial direction with respect to the left and right fluid chambers respectively acts on the both 5 and 6 with the vibration of the building B, the first The second pressure receiving portions 5 and 6 are held by the pressure of the working fluid HF in the corresponding first and second fluid chambers 2j to 2m so as not to move in the axial direction with respect to the left and right fluid chambers.

  As described above, during the vibration of the building B, the pressure of the working fluid HF causes the relative rotation between the support shaft 3 and the main body 2 with respect to the main body 2, the support shaft 3, and the first and second pressure receiving parts 5 and 6. While the main body 2 is not moved in the axial direction or the radial direction from the support shaft 3, whereby the main body 2 is rotatably held with respect to the support shaft 3. Thus, the working fluid HF and the first and second pressure receiving portions 5 and 6 function as a so-called fluid bearing. In this case, unlike the above-described conventional mass damper, the mass damper 1 does not have a pair of fluid chambers and a pressure receiving portion (piston) but a pair of left and right fluid chambers and first and second pressure receiving portions 5 and 6 as a fluid bearing. Are provided, and the first and second pressure receiving portions 5 and 6 can receive the pressure (reaction force) of the working fluid HF. The axial load to be applied can be sufficiently borne, so that the rotational inertia mass effect of the main body 2 can be appropriately obtained.

  In addition, the first and second fluid chambers 2j are input when external forces in the directions of moving the first and second pressure receiving parts 5, 6 in the axial direction with respect to the pair of fluid chambers are respectively input to the two fluid chambers 5, 6. ~ 2m, when the pressure of the working fluid HF in one of the first and second fluid chambers 2j, 2k (21, 2m) partitioned by each pressure receiving portion 5 (6) reaches the limit value, Immediately before the pressure of the working fluid HF becomes excessive, the pressure of the working fluid HF in one of the first and second fluid chambers 2j, 2k (21, 2m) is increased by the relief mechanism 11 to the first and second fluid chambers 2j. , 2k (2l, 2m). This allows the first and second pressure receiving portions 5 and 6 to move in the axial direction with respect to the pair of fluid chambers, respectively, so that the load acting on the mass damper 1 in the axial direction (hereinafter referred to as “axial load”). ) Can be prevented from becoming excessive.

  Further, since the main body 2 and the rotating mass are made of a common member, the number of parts can be reduced accordingly, and the manufacturing cost can be reduced, and the mass damper 1 can be simply constructed. Can be.

  Next, a mass damper 21 according to a second embodiment of the present invention will be described with reference to FIG. In the following description, for convenience, the left side and the right side of FIG. 4 are treated as “left” and “right”, respectively. Compared to the first embodiment, the mass damper 21 has a first partition wall 23 and a second partition wall 24 in which the first and second pressure receiving portions 22d and 22e define a pair of left and right fluid chambers in the main body 22. The third partition wall 25 and the third partition wall 25 are provided integrally with the support shaft 3, and the configuration of the relief mechanism is mainly different. In FIG. 4, the same components as those in the first embodiment are denoted by the same reference numerals. Hereinafter, the points different from the first embodiment will be mainly described.

  As in the first embodiment, the main body 22 is made of a material having a relatively large specific gravity, for example, iron, and has a cylindrical peripheral wall 22a extending in the left-right direction (axial direction) and left and right ends of the peripheral wall 22a. Donut plate-shaped left and right side walls 22b and 22c provided coaxially and integrally, and a donut plate-shaped first pressure receiving portion 22d and a donut plate provided coaxially and integrally provided on the left side of the peripheral wall 22a in order from the left. It has two pressure receiving portions 22e, and the main body portion 22 and the rotating mass are formed of members common to each other. That is, the main body 22 is also used as a rotating mass as in the first embodiment. The left side wall 22b, the first and second pressure receiving portions 22d and 22e, and the right side wall 22c are formed with insertion holes 22f, 22g, 22h and 22i penetrating in the left and right direction, respectively. 22i is arranged coaxially with the peripheral wall 22a.

  The first to third partition walls 23, 24 and 25 are coaxially and integrally provided on the right portion of the support shaft 3, and the first to third partition walls 23 to 25 are formed in a disc shape. They are formed and are arranged in this order from the left side with a space between them in the left-right direction. The outer peripheral surfaces of the first to third partition walls 23 to 25 are provided with seals, and are in contact with the inner peripheral surface of the peripheral wall 22a via the seals. In the main body 22, a pair of left and right fluid chambers is defined by the peripheral wall 22a and the first to third partition walls 23 to 25, and the pair of fluid chambers is densely filled with the working fluid HF. ing. The pressure of the working fluid HF acts on the main body 22 so as to radially press the entire inner peripheral surface thereof.

  The first and second pressure receiving portions 22d and 22e are housed in the left and right fluid chambers of the pair of fluid chambers together with the right portion of the support shaft 3, respectively. . The left fluid chamber is partitioned into a left first fluid chamber 22j and a right second fluid chamber 22k by a first pressure receiving part 22d, and the right fluid chamber is partitioned by a second pressure receiving part 22e. It is partitioned into a chamber 221 and a second fluid chamber 22m on the right side. Thus, since the right part of the support shaft 3 is accommodated in the left and right fluid chambers, the pressure of the working fluid HF in the left and right fluid chambers presses the entire outer peripheral surface of the support shaft 3 toward the center thereof. Act on. Further, the first and second pressure receiving portions 22d and 22e are respectively held so as not to move in the left and right directions with respect to the left and right fluid chambers due to the pressure of the working fluid HF in the corresponding first and second fluid chambers 22j to 22m. Have been.

  In the relief mechanism, similarly to the relief mechanism 11 of the first embodiment, the pressure of the working fluid HF in each of the first and second fluid chambers 22j to 22m becomes excessive to prevent the axial load of the mass damper 21 from becoming excessive. Immediately before, the pressure of the working fluid HF in one of the first and second fluid chambers 22j, 22k (221, 22m) is released to the other, so that the first and second pressure receiving portions 22d, 22e are moved to the left and right fluid chambers. This is to allow each to move. Specifically, the relief mechanism includes first and second relief valves 31 and 32 provided in the first pressure receiving portion 22d and first and second relief valves 33 and 34 provided in the second pressure receiving portion 22e. Have. These first and second relief valves 31 to 34 are constituted by a valve body and a spring for urging the valve body in the valve closing direction, similarly to the first relief valve 14 of the first embodiment. The first pressure receiving portion 22d is formed with a pair of communication holes penetrating in the left-right direction, and the pair of communication holes are provided with first and second relief valves 31, 32, respectively.

  When the pressure of the working fluid HF in the first fluid chamber 22j is smaller than the upper limit value, the first relief valve 31 closes the communication hole of the corresponding first pressure receiving portion 22d. The communication hole of the pressure receiving portion 22d is opened. By opening the communication hole of the first pressure receiving portion 22d by the first relief valve 31, the first and second fluid chambers 22j and 22k communicate with each other via the communication hole of the first pressure receiving portion 22d. When the pressure of the working fluid HF in the second fluid chamber 22k is smaller than the upper limit, the second relief valve 32 closes the communication hole of the corresponding first pressure receiving portion 22d. The communication hole of the part 22d is opened. When the communication hole of the first pressure receiving portion 22d is opened by the second relief valve 32, the second and first fluid chambers 22k and 22j communicate with each other via the communication hole of the first pressure receiving portion 22d.

  Similarly to the first pressure receiving portion 22d, the second pressure receiving portion 22e is formed with a pair of communication holes penetrating in the left-right direction. The first and second relief valves 33 are provided in the pair of communication holes. , 34 are provided. When the pressure of the working fluid HF in the first fluid chamber 221 is smaller than the upper limit value, the first relief valve 33 closes the communication hole of the corresponding second pressure receiving portion 22e. The communication hole of the part 22e is opened. By opening the communication hole of the second pressure receiving portion 22e by the first relief valve 33, the first and second fluid chambers 221 and 22m communicate with each other via the communication hole of the second pressure receiving portion 22e. When the pressure of the working fluid HF in the second fluid chamber 22m is smaller than the upper limit, the second relief valve 34 closes the communication hole of the corresponding second pressure receiving portion 22e. The communication hole of the part 22e is opened. When the communication hole of the second pressure receiving portion 22e is opened by the second relief valve 34, the second and first fluid chambers 22m and 22l communicate with each other via the communication hole of the second pressure receiving portion 22e.

  In the mass damper 21 configured as described above, the pressure of the working fluid HF filled in the pair of fluid chambers is applied to the support shaft 3 and the first and second pressure receiving portions 22d and 22e between the support shaft 3 and the main body 22. Acts so as not to move the main body portion 22 from the support shaft 3 in the axial direction (left-right direction) or radial direction while allowing the main body portion 22 to rotate with respect to the support shaft 3. Will be retained. As described above, the working fluid HF and the first and second pressure receiving portions 22d and 22e function as fluid bearings as in the first embodiment.

  The mass damper 21 is connected to the upper and lower beams BU and BD of the building B in the same manner as in the first embodiment (see FIG. 3). When a relative displacement occurs between the upper and lower beams BU and BD due to the vibration of the building B, and thereby a compressive force acts on the mass damper 21, the compressive force causes the support shaft 3 and the screw shaft 4a to move to the main body. It acts to move to the right and left with respect to 22, respectively. In this case, the compressive force acts on the first to third partition walls 23 to 25 integral with the support shaft 3 so as to move the main unit 22 to the right, and accordingly, the first fluid chamber 22j. , 22l are pressed by the first and second pressure receiving portions 22d, 22e integral with the main body 22, respectively, so that the pressure increases. When the pressure of the working fluid HF in the first fluid chambers 22j and 22l has not reached the upper limit, the corresponding communication holes of the first and second pressure receiving portions 22d and 22e are closed by the first relief valves 31 and 33, respectively. Held in state. In this case, since the working fluid HF in the second fluid chambers 22k and 22m is not pressed by the first and second pressure receiving portions 22d and 22e, respectively, the pressure does not reach the upper limit value. By 34, the corresponding communication holes of the first and second pressure receiving portions 22d and 22e are also kept closed.

  As described above, when the pressure of the working fluid HF in the first fluid chambers 22j and 221 does not reach the upper limit when the compressive force acts on the mass damper 21, the working fluid HF in the first fluid chambers 22j and 221 becomes The main body portion 22, the first and second pressure receiving portions 22d and 22e, and the support shaft 3 do not flow to the two fluid chambers 22k and 22m, and the pressure of the working fluid HF in the first and second fluid chambers 22j to 22m. As a result, they are held so as not to move relative to each other in the left-right direction. The screw shaft 4a moves leftward due to the above-described compression force, and accordingly, the nut 4c rotates together with the main body 22. As described above, when the compressive force acts on the mass damper 21 in accordance with the vibration of the building B, the relative displacement between the upper and lower beams BU and BD is determined via the support shaft 3, the screw shaft 4a, and the nut 4c. The rotational motion is transmitted to the main body 22 in a state where it is converted, whereby the main body 22 also serving as a rotating mass rotates.

  When the pressure of the working fluid HF in the first fluid chambers 22j and 22l reaches the upper limit value when the compressive force acts on the mass damper 21, the first and second pressure receiving portions are activated by the first relief valves 31 and 33. The corresponding communication holes of 22d and 22e are respectively opened, and a part of the working fluid HF in the first fluid chambers 22j and 22l flows through the communication holes to the second fluid chambers 22k and 22m. Thereby, the pressure of the working fluid HF in the first fluid chambers 22j and 22l is released to the second fluid chambers 22k and 22m, so that the first and second pressure receiving portions 22d and 22e with respect to the pair of fluid chambers move to the left. Movement is allowed respectively.

  On the other hand, when a tensile force acts on the mass damper 21, the tensile force causes the support shaft 3 and the first to third partition walls 23 to 25 to the left with respect to the main body 22 and the screw shaft 4 a to the main body 22. To the right. Accordingly, the working fluid HF in the second fluid chambers 22k and 22m is pressed by the first and second pressure receiving portions 22d and 22e, respectively, so that the pressure increases. When the pressure of the working fluid HF in the second fluid chambers 22k and 22m has not reached the upper limit, the corresponding communication holes of the first and second pressure receiving portions 22d and 22e are closed by the second relief valves 32 and 34, respectively. Held in state. In this case, the working fluid HF in the first fluid chambers 22j and 22l is not pressed by the first and second pressure receiving portions 22d and 22e, respectively, and the pressure does not reach the upper limit value. 33, the corresponding communication holes of the first and second pressure receiving portions 22d and 22e are also kept closed.

  As described above, when the pulling force acts on the mass damper 21, when the pressure of the working fluid HF in the second fluid chambers 22k and 22m does not reach the upper limit, the working fluid HF in the second fluid chambers 22k and 22m becomes The main body 22, the first and second pressure receiving parts 22d and 22e, and the support shaft 3 do not flow to the one fluid chambers 22j and 22l, and the pressure of the working fluid HF in the first and second fluid chambers 22j to 22m. As a result, they are held so as not to move relative to each other in the left-right direction. The screw shaft 4a moves rightward due to the above-described tensile force, and accordingly, the nut 4c rotates together with the main body 22. As described above, even when a tensile force acts on the mass damper 21 due to the vibration of the building B, the relative displacement between the upper and lower beams BU and BD rotates through the support shaft 3, the screw shaft 4a, and the nut 4c. By being transmitted to the main body 22 in a state converted into motion, the main body 22 rotates.

  When the pressure of the working fluid HF in the second fluid chambers 22k and 22m reaches the upper limit value in the case where the tensile force acts on the mass damper 21, the first and second pressure receiving portions are operated by the second relief valves 32 and 34. The corresponding communication holes of 22d and 22e are opened, respectively, and a part of the working fluid HF in the second fluid chambers 22k and 22m flows to the first fluid chambers 22j and 22l through these communication holes, respectively. As a result, the pressure of the working fluid HF in the second fluid chambers 22k and 22m is released to the first fluid chambers 22j and 22l, so that the first and second pressure receiving portions 22d and 22e with respect to the pair of fluid chambers move to the right. Movement is allowed respectively.

  As described above, according to the second embodiment, as in the first embodiment, a pair of left and right fluid chambers, two sets of fluid chambers including the first and second pressure receiving portions 22d and 22e, and the pressure receiving portions 22d and 22e are provided. The first and second pressure receiving portions 22d and 22e can receive the pressure of the working fluid HF. Therefore, the axial load input to the mass damper 21 can be sufficiently borne, whereby the rotational inertia mass effect of the main body 22 can be appropriately obtained.

  Further, similarly to the first embodiment, in each of the first and second fluid chambers 22j to 22m, the first and second fluid chambers 22j and 22k (221, 22m) partitioned by each pressure receiving portion 22d (22e) are provided. When the pressure of the working fluid HF on one side reaches the limit value, that is, immediately before the pressure of the working fluid HF becomes excessive, the working fluid HF in one of the first and second fluid chambers 22j and 22k (221, 22m). Is released to the other of the first and second fluid chambers 22j and 22k (221, 22m) by the relief mechanism (first and second relief valves 31 to 34). This allows the first and second pressure receiving portions 22d and 22e to move in the axial direction in the pair of fluid chambers, respectively, so that the axial load of the mass damper 21 (the load acting in the axial direction) becomes excessive. Can be prevented.

  Further, as in the first embodiment, since the main body 22 and the rotating mass are formed of members common to each other, the number of parts can be reduced accordingly, and the manufacturing cost can be reduced, and the mass damper can be reduced. 21 can be easily configured.

  The present invention is not limited to the first and second embodiments described above, but can be implemented in various modes. For example, in the first embodiment, the relief mechanism in the present invention is configured by combining the first and second communication passages 12 and 13 and the first and second relief valves 14 to 17, but the second embodiment As in the embodiment, the first and second pressure receiving portions may be configured by first and second relief valves, respectively. Similarly, in the second embodiment, the relief mechanism in the present invention is configured by the first and second relief valves 31 to 34 provided in the first and second pressure receiving portions 22d and 22e, respectively. As in the first embodiment, the first and second communication passages and the first and second relief valves may be combined.

  Further, in the first and second embodiments (hereinafter, collectively referred to as “embodiments”), the working fluid HF made of silicone oil is used, but another appropriate fluid may be used. Furthermore, in the embodiment, the main body parts 2 and 22 and the rotating mass are configured by a common member, but may be configured by separate members. In this case, by providing the rotating mass integrally outside the main body, an effect of facilitating the adjustment of the rotating inertial mass of the rotating mass can be obtained. Further, the rotating mass may be integrally provided inside the main body, and the present invention does not exclude such a configuration.

  Further, in the embodiment, the mass dampers 1 and 21 are provided so as to extend in the left-right direction on the upper and lower beams BU and BD via the V-shaped brace material BR, but are provided via the inverted V-shaped brace material. Thus, the upper and lower beams may be provided so as to extend in the left-right direction. In any of these cases, a pair of mass dampers may be provided so as to extend from the gathered portion of the brace material to the opposite sides. Alternatively, the mass damper may be provided in a brace shape on the upper and lower beams, and may be provided so as to extend in the vertical direction to suppress vertical displacement between the upper and lower beams due to vibration. Alternatively, two mass dampers may be provided on the upper and lower beams in a V-shape or an inverted V-shape.

  Further, in the embodiment, the upper and lower beams BU and BD are adopted as the objects to which the mass dampers 1 and 21 are connected, and the interlayer displacement between the two layers is suppressed. However, other appropriate parts may be adopted. . For example, as a target to which the mass damper is connected, upper and lower beams provided with one or more beams between each other may be adopted to suppress interlayer displacement between three or more layers, or the building B may be used. Erect foundations and beams may be employed. In the embodiment, the displacement in the left-right direction due to the vibration of the building B is suppressed by connecting the mass dampers 1 and 21 to the beams BU and BD extending in the left-right direction. Thereby, the displacement in the front-rear direction due to the vibration of the building may be suppressed.

  Furthermore, in the embodiment, the mass dampers 1 and 21 are installed between the layers of the building B and used as a vibration damping device. However, the present invention is not limited to this, and the mass dampers 1 and 21 may be installed between a structure and a support that supports the same. It may be used as a vibration device. Further, the embodiment is an example in which the mass dampers 1 and 21 according to the present invention are applied to a high-rise building B, but the present invention is not limited to this and can be applied to other appropriate structures such as a steel tower and a bridge. It is. In addition, the configuration of the details can be appropriately changed within the scope of the present invention.

B Building (structure)
BU Upper beam (2nd part)
BD Lower beam (1st part)
1 Mass damper 2 Main body (rotating mass)
2b Left side wall (first wall)
2d 1st partition wall (2nd wall part)
2e Second partition wall (third wall)
2j First fluid chamber (two fluid chambers)
2k 2nd fluid chamber (2 fluid chambers)
2l first fluid chamber (two fluid chambers)
2m 2nd fluid chamber (2 fluid chambers)
3 Support shaft 4a Screw shaft 4b Ball 4c Nut 5 First pressure receiving part (a pair of pressure receiving parts)
6 2nd pressure receiving part (a pair of pressure receiving parts)
11 Relief mechanism HF Working fluid 21 Mass damper 22 Main body (rotating mass)
22d first pressure receiving portion 22e second pressure receiving portion 22j first fluid chamber (two fluid chambers)
22k second fluid chamber (two fluid chambers)
22l first fluid chamber (two fluid chambers)
22m 2nd fluid chamber (2 fluid chambers)
23 1st partition wall (1st wall part)
24 2nd partition wall (2nd wall part)
25 Third partition wall (third wall)
31 1st relief valve (relief mechanism)
32 2nd relief valve (relief mechanism)
33 1st relief valve (relief mechanism)
34 2nd relief valve (relief mechanism)

Claims (3)

A mass damper provided between a first portion and a second portion in a system including a structure, for suppressing vibration of the structure,
A cylindrical main body,
A rotating mass provided integrally with the main body,
A screw shaft connected to the first portion and extending in the axial direction of the main body portion, and provided at one portion of the main body portion in the axial direction so as to be movable in the axial direction and coaxially;
A nut screwed onto the screw shaft via a ball, and a nut attached to the one portion of the main body;
A support shaft connected to the second portion and extending in the axial direction, provided coaxially with the other portion of the main body portion in the axial direction, and rotatably supporting the main body portion;
A first wall portion, a second wall portion, and a second wall portion which are integrally provided on one of the main body portion and the support shaft with a space therebetween in the axial direction, and define a pair of fluid chambers in the main body portion. Three walls,
A working fluid filled in the pair of fluid chambers,
The pair of fluid chambers are provided integrally with the other of the main body and the support shaft, and each of the pair of fluid chambers is divided into two fluid chambers in the axial direction. A pair of pressure receiving portions each held so as not to move in the axial direction with respect to the chamber,
The mass damper, wherein the main body is held rotatably with respect to the support shaft by the pressure of the working fluid.   An external force in a direction to move the pair of pressure receiving portions in the axial direction with respect to the pair of fluid chambers is input to the pair of pressure receiving portions, so that the two fluids are respectively supplied to the pair of fluid chambers. Immediately before the pressure of the working fluid in one of the chambers becomes excessive, the pressure of the working fluid in the one of the two fluid chambers is released to the other of the two fluid chambers, thereby allowing the pair of pressure receiving parts to move. The mass damper according to claim 1, further comprising a relief mechanism for performing the operation.   3. The mass damper according to claim 1, wherein the main body and the rotating mass are formed of a common member. 4.

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