JP2013148207A - Vibration damping device for support column and support column - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new vibration damping device for a support column, having a function of reducing the natural vibration (especially, primary vibration) of the support column.SOLUTION: This vibration damping device 200 for a support column includes: a bracket 202 having a fixed part 222 fixed to the support column 100 (a support column body 102) and a flange part 224 extending radially outward from the fixed part 222; a rubber 204 attached to the upper part or the lower part of the flange part 224; and a weight 206 attached to the rubber 204 on the side opposite the flange part 224. The vibration damping device for a support column can attenuate the vibration of the support column earlier.

Description

  The present invention relates to a strut damping device and a strut.

  Posts such as road signs, road equipment (lighting, street lamps), and power poles vibrate due to the influence of wind and the influence of vehicle travel. For example, in a viaduct, the viaduct swings as the vehicle travels. Road signs and road laying equipment installed on the viaduct vibrate as the viaduct swings. Such vibration is small, but is applied to the column for a long time and continuously. For this reason, in a road sign or a road equipment column, the column or anchor bolt may be damaged due to metal fatigue (for example, if the column is a hollow tube, a crack may occur). For this reason, regular maintenance is required.

  Various proposals have been made on such a strut regarding a vibration damping device that attenuates input vibrations caused by wind or running of a vehicle. For example, a combination of a weight and a spring (JP-A-9-143939), a combination of a spring and an oil damper (JP-A-5-187482), a form immersed in a viscous fluid (JP-A-2006) -71095 gazette), and a form (Japanese Patent Laid-Open No. 2007-239906) attached to the outside of the column as a pendulum has been proposed. Further, there have been proposed a configuration in which a vibration absorber is sandwiched between a support column and a fixed portion (Japanese Patent Laid-Open No. 2001-73329), and a mode in which a vibration absorber is embedded in the support column (Japanese Patent Laid-Open No. 2001-207688). . In addition, a form in which a chain is hung inside a support (Patent No. 4493090, Japanese Patent Application Laid-Open No. 2006-226038), and a form in which a block in which a viscous fluid and a plate for restricting the flow are arranged are installed inside the support (Japanese Patent Application Laid-Open No. 2007-2007) No. -127210), and a form in which a pendulum is hung (Japanese Patent Laid-Open No. 2007-170415, Japanese Patent No. 3222863) has been proposed.

Japanese Patent Laid-Open No. 9-143939, paragraphs 0012 to 0014, FIG. Japanese Patent Laid-Open No. 5-187482 JP 2006-71095 A JP 2007-239906 A JP 2001-73329 A JP 2001-207688 A Japanese Patent No. 4493090 JP 2006-226038 A JP 2007-127210 A JP 2007-170415 A Japanese Patent No. 3222863

  For example, the vibration damping device disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 9-143939) is built in the protruding portion of the curved tip of the steel pipe column (see paragraph 0012 of the same publication). The vibration damping device disclosed here includes a coil spring having one end fixed to a fixed portion and a weight attached to one end of the coil spring. Such a strut damping device functions to suppress vibration in one direction in which the coil spring expands and contracts. Since the coil spring expands and contracts along the guide, a sufficient function may not be obtained for vibrations in other directions. Moreover, although the tip is curved and attached to the projecting steel pipe column, it cannot be applied to other columns.

  The present inventor proposes a novel strut damping device that exerts a damping action on the natural vibration (particularly, primary vibration) of the strut using the mass.

  A strut damping device according to an embodiment of the present invention is attached to a bracket having a mounting portion attached to a strut, a flange portion extending radially outward from the mounting portion, and an upper portion or a lower portion of the flange portion. A rubber and a weight attached to the rubber on the side opposite to the flange portion are provided. According to such a strut damping device, vibration of the strut can be attenuated at an early stage.

  Here, the weight and rubber may be exchangeable. In addition, the bracket may be a ring-shaped member that is attached to the peripheral side surface of the column to which the bracket is attached. The bracket may be divided in the circumferential direction, and may include a restraining member that restrains the bracket in a state of being attached to the circumferential side surface of the support column. The bracket may include a hinge that connects members divided in the circumferential direction. A plurality of rubbers and weights may be arranged. In this case, the rubber and the weight may be arranged along a concentric circle with respect to the axis of the column to which the bracket is attached. Further, the weight is an annular member, and the rubber may support the weight at a plurality of positions in the circumferential direction with respect to the column to which the bracket is attached.

  The rubber and the weight may be attached to the upper side of the flange portion, and may have a sliding bearing that supports the weight between the weight and the flange portion. The rubber is preferably a high-damping rubber having a loss coefficient tan δ of 0.2 to 1.2 at a shear strain of 3% to 20%.

  Further, the support column according to an embodiment of the present invention is attached to a support column body that is erected on the installation portion, a flange that is attached to the support column body, extends radially outward from the support column body, and an upper or lower portion of the flange. And a weight attached to the rubber on the side opposite to the flange.

  In this case, the flange may be attached at a position that is half the height of the column main body or higher than half the height of the column main body. In addition, in the state where the natural frequency A of the strut damping part (strut damping device) composed of the flange, rubber, and weight is not attached to the member constituting the strut damping part The ratio (A / B) with the natural frequency B of the support body is preferably 0.5 ≦ (A / B) ≦ 1.5.

FIG. 1 is a side view showing a strut damping device and a strut according to an embodiment of the present invention. FIG. 2 is a side view of the vibration damping device for a column attached to the column main body. FIG. 3 is a plan view of a column vibration damping device attached to the column main body. FIG. 4 is a view of the bracket attached to the column main body as viewed from below. FIG. 5 is a side view showing a state in which vibration is generated in the support column. FIG. 6 is a view showing a strut damping device according to another embodiment. FIG. 7 is a view showing a bracket according to another embodiment. FIG. 8 is a view showing a strut damping device according to another embodiment. FIG. 9 is a diagram showing a strut damping device according to another embodiment. FIG. 10: is a figure which shows the state which the vibration generate | occur | produced in the support | pillar about the support | pillar damping device which concerns on another form. FIG. 11 is a diagram illustrating a strut damping device according to another embodiment. FIG. 12 is a diagram illustrating a strut damping device according to another embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a strut damping device and a strut according to an embodiment of the present invention will be described with reference to the drawings. In addition, this invention is not limited to the following embodiment. Moreover, the same code | symbol is attached | subjected suitably to the member or site | part which has the same effect | action. The drawings are schematically drawn to aid in understanding the invention and do not necessarily represent the real thing.

≪Strut 100≫
FIG. 1 is an external view of a column 100 to which a column vibration damping device according to an embodiment of the present invention is attached. As shown in FIG. 1, the support column 100 includes a support column main body 102 and a support vibration damping device 200.

≪Main body 102≫
The column main body 102 is erected on the installation portion 300. Here, the installation part 300 is a part (place) where the column 100 is installed, such as the ground, a road, and a viaduct shoulder. The column body 102 is made of a steel pipe. The column main body 102 extends vertically at a predetermined height, its tip is curved and projects in a radial direction, and a street lamp 104 is attached. As described above, the column main body 102 includes the upright portion 121 extending vertically, the protruding portion 122 protruding in a curved manner, and the distal end portion 123 to which the street light 104 is attached. In this embodiment, the strut damping device 200 is attached to the upright portion 121 of the strut body 102 that extends vertically.

≪Strut damping device 200≫
As shown in FIG. 1, the strut damping device 200 includes a bracket 202, rubber 204, and a weight 206. FIG. 2 is a side view of the strut damping device 200 attached to the strut body 102. FIG. 3 is a plan view of the strut damping device 200 attached to the strut body 102.

<Bracket 202>
The bracket 202 is attached to the column main body 102. In this embodiment, as shown in FIGS. 2 and 3, the bracket 202 is a substantially disk-like member, and has a mounting portion 222 and a flange portion 224 (flange).

  FIG. 4 is a view of the bracket 202 attached to the column main body 102 as viewed from below. The attachment portion 222 is provided on the lower side of the bracket 202. The attachment portion 222 is provided at the center of the bracket 202 (flange portion 224), and includes a boss portion 226 and a restraining portion 228. The boss portion 226 has an insertion hole 227 through which the column main body 102 is inserted. In this embodiment, the flange portion 224 and the boss portion 226 are divided into a semi-disc shape and a semi-cylindrical shape, respectively. The restraining portion 228 restrains the flange portion 224 and the boss portion 226 while being attached to the column main body 102. In this embodiment, the restraining portion 228 is composed of mating pieces 231 and 232 that extend in the radial direction from both ends of the boss portion 226 that is split on the semi-cylinder, and a bolt nut 234 that tightens the mating pieces 231 and 232. Yes. In this embodiment, restraining plates 238 and 239 for fixing the mating surfaces are attached to the lower portion of the flange portion 224. The restraining plates 238 and 239 are preferably attached detachably with screws.

  In this embodiment, the bracket 202 is attached at a position higher than half the height of the column main body 102 as shown in FIG. Here, the height of the column main body 102 is defined by the height h1 of the upright portion 121 of the column main body 102, and is attached at a position higher than half the height h2 of the upright portion 121. Specifically, in this embodiment, the bracket 202 is attached to the upper part of the column main body 102. Here, the position of the bracket 202 is adjusted so that the uppermost portion of the weight 206 is aligned with the highest position of the upright portion 121 of the column main body 102. Note that the bracket 202 may be attached above a height h4 that is half of the total height h3 of the column main body 102, including the overhang portion 122 and the tip portion 123.

  As shown in FIG. 4, the bracket 202 is fixed to the column main body 102 by tightening the bolt nut 234 in a state where the column main body 102 is sandwiched between the boss portions 226. A rubber 204 is attached to the bracket 202.

<Rubber 204>
In this embodiment, the rubber 204 is attached to the upper portion of the flange portion 224 of the bracket 202. The rubber 204 has a cylindrical shape that can be disposed on the flange portion 224 of the bracket 202. For example, the rubber 204 may be attached to the flange portion 224 of the bracket 202 by vulcanization adhesion.

  The rubber 204 is disposed at a plurality of positions in the circumferential direction with respect to the column main body 102 to which the bracket 202 is attached. In this embodiment, as shown in FIG. 3, the four rubbers 204 are evenly arranged in the circumferential direction of the flange portion 224. The rubber 204 is preferably provided with a required strength to the extent that it can support a vertical load of a weight 206 described later. As the rubber 204, for example, a molded body of high attenuation rubber or laminated rubber (including high attenuation laminated rubber, laminated rubber with a lead plug, etc.) can be used.

<Weight 206>
The weight 206 is attached to the rubber 204 on the side opposite to the flange portion 224. In this embodiment, the weight 206 is attached to the upper end of the rubber 204. The weight 206 is an annular member disposed so as to surround the support body 102. The weight 206 is supported by a plurality of rubbers 204 attached to the bracket 202. As shown in FIGS. 2 and 3, the weight 206 and the column main body 102 are provided with a required gap S <b> 1. In this embodiment, since the weight 206 swings with respect to the support body 102, the weight 206 is set so as not to hit the support body 102.

  In this embodiment, the bracket 202 can be divided, and the weight 206 can be divided in the same manner. For example, as shown in FIGS. 2 and 3, the weight 206 can be divided at least in the circumferential direction so that it can be divided according to the division of the bracket 202, and can be connected by a connecting member 236 such as a bolt nut or a rivet. It is configured. 2 and 3 schematically show the dividing surface 237 of the weight 206 and the connecting member 236.

  The weight 206 is supported via rubber 204. Therefore, as shown in FIG. 5, the weight 206 swings with respect to the bracket 202 when vibration occurs in the column main body 102. The weight 206 is preferably provided with a required weight so that, when vibration occurs in the column main body 102, the column main body 102 can be shaken by an inertial force to reduce the vibration of the column main body 102.

<< Molding of rubber 204 >>
As the rubber 204, for example, a sheet-like unvulcanized high-damping rubber having a predetermined thickness, width, and length is prepared. Such unvulcanized high-damping rubber is wound into a cylindrical shape and placed in a predetermined mold. Then, the flange portion 224 of the bracket 202 is pressed against one end of the high damping rubber housed in a cylindrical shape in the mold, and the weight 206 is pressed against the other end. At this time, a rubber vulcanized adhesive (for example, made by LORD (USA: LORD Far East, Inc): rubber vulcanized adhesive (trade name “Chemlock”)) is applied to the flange portion 224 and the weight 206. . In this state, the rubber 204 (high damping rubber) is molded by vulcanization heating, and the flange portion 224 of the bracket 202 and the rubber 204, and the rubber 204 and the weight 206 are bonded. At this time, the natural frequency and damping performance of the strut damping device 200 can be adjusted by, for example, the height and hardness of the rubber 204 (for example, the loss coefficient tan δ) and the weight of the weight 206.

≪Action on vibration≫
According to the column 100, the weight 206 is supported via the rubber 204 with respect to the bracket 202 attached to the column main body 102. For this reason, when vibration occurs in the column main body 102 due to traffic vibration or a windy earthquake, the weight 206 swings relative to the column main body 102. Further, in this embodiment, the strut damping device is attached at a position higher than half the height of the strut body 102. In particular, the weight 206 is attached to the highest position of the upright portion 121 of the column main body 102.

  In the column main body 102, in the primary vibration, the upright portion 121 of the column main body 102 swings greatly toward the upper part. For this reason, the bracket 202 attached to the upper part of the column main body 102 also swings greatly. At this time, an inertial force acts on the weight 206 of the strut damping device 200 according to the movement of the bracket 202. Since the weight 206 is supported via the rubber 204, the weight 206 swings with respect to the bracket 202. In this embodiment, the weight 206 has a disk shape and is supported by a plurality of rubbers 204 arranged in the circumferential direction on the bracket 202.

  Further, shear deformation occurs in the rubber 204 in accordance with the swing movement of the weight 206. The rubber 204 (high damping rubber) accompanied by the shear deformation can also absorb the energy of vibration acting on the column main body 102. At this time, energy corresponding to the area surrounded by the hysteresis loop accompanying the shear deformation of the rubber 204 can be absorbed. Moreover, according to this support | pillar damping device 200, the vibration which acts on the support | pillar main body 102 can be attenuated irrespective of the direction of a vibration.

  In the above, the support | pillar damping device 200 and the support | pillar 100 which concern on one Embodiment of this invention were demonstrated. The strut damping device and the strut according to the present invention are not limited to the above-described embodiments. Hereinafter, various modifications will be described. The modifications listed here can be applied independently and may be combined as appropriate.

  For example, in the above-described embodiment, the weight 206 is bonded to the rubber 204, but the weight 206 may be attached to the rubber 204 in an exchangeable manner. Accordingly, for example, the weight 206 can be replaced with a weight having a different weight, and the weight of the weight 206 of the strut damping device 200 can be changed. Thereby, when attaching to the support | pillar main body 102 on the spot, the weight 206 of suitable weight can be attached suitably, for example. FIG. 6 shows a strut damping device 200A according to another embodiment. In this case, as shown in FIG. 6, an attachment member (for example, an attachment plate 252) may be bonded to the rubber 204, and the weight 206 may be attached to the attachment member 252 in a replaceable manner.

  Further, the weight of the weight 206 may be adjusted. For example, the mass body may be attached to an arbitrary position of the weight 206. With this configuration, the weight of the weight 206 of the strut damping device 200 can be adjusted as appropriate. For example, an attachment hole (screw hole) may be formed at an arbitrary position of the weight 206, and the adjustment weight 262 may be appropriately attached. Such an adjustment weight 262 may be made of a metal having a relatively high specific gravity, such as tungsten.

  For example, as shown in FIG. 1, when the tip of the column main body 102 is curved and protrudes in the radial direction, the weight 206 is weighted around the column main body 102 in consideration of the protrusion. Adjust it. Thereby, the behavior of the column main body 102 when vibration is generated can be stabilized.

  The rubber 204 may be attached to the bracket 202 (flange portion 224) in a replaceable manner. Thereby, for example, the rubber 204 can be replaced with a rubber having a different loss coefficient with respect to the shear strain. Further, even when the rubber 204 has deteriorated over time, it is only necessary to replace the rubber 204, so that the cost can be kept small during maintenance. In this case, for example, an attachment member (for example, an attachment plate 254) may be bonded to the rubber 204 and attached to the bracket 202 via the attachment member 254 in a replaceable manner.

<Sliding bearing 270>
Further, as shown in FIG. 6, the rubber 204 and the weight 206 are attached to the upper side of the flange portion 224, and a sliding bearing 270 that supports the weight 206 is provided between the weight 206 and the flange portion 224. Good. Here, the sliding support 270 supports the load of the weight 206 by the member 271 attached to the flange portion 224 by superimposing the member 271 attached to the flange portion 224 and the member 272 attached to the weight 206. Further, the member 272 attached to the weight 206 is configured to slide relative to the member 271 attached to the flange portion 224 in accordance with the shear displacement of the weight 206. Further, the sliding bearing 270 is configured at substantially the same height as the rubber 204.

  The sliding support 270 prevents the weight 206 from being inclined with respect to the flange portion 224. In response to the vibration acting on the column main body 102, the weight 206 smoothly shears and displaces with respect to the flange portion 224, and the shear displacement acts appropriately by the rubber 204. Further, the vertical load of the weight 206 can be prevented from acting on the rubber 204, and the characteristics of the rubber 204 can be maintained high with respect to the shear displacement of the weight 206. Further, the sliding bearing 270 is configured at substantially the same height as the rubber 204. For this reason, since the vertical load of the weight 206 hardly acts on the rubber 204, the life of the rubber 204 can be improved.

<Hinge 276>
Further, the bracket 202 may be a ring-shaped member as described above. Further, the bracket 202 can be divided in the circumferential direction, and may include a restraining member (for example, a bolt nut 234) that restrains the bracket 202 in a state of being attached to the circumferential side surface of the support column. The bracket 202 is not limited to such a form. For example, FIG. 7 shows a bracket 202A according to another embodiment. As shown in FIG. 7, the bracket 202 </ b> A includes a hinge 276 that can be divided in the circumferential direction and connects members divided in the circumferential direction.

  In the example shown in FIG. 7, the mating pieces 231a and 232a extending in the radial direction from one end of the boss portion 226A split on the semi-cylinder are arranged along the radial direction of the flange portion 224A of the bracket 202A. It extends to. The hinge 276 is provided on the outer peripheral edge of the flange portion 224, and connects the mating pieces 231a and 232a so as to be bent. A restraining portion 228A is provided on the mating pieces 231b and 232b extending from the other end of the boss portion 226A to the opposite side. The restraining portion 228A is configured by a bolt nut 234A that is tightened in a state where the mating pieces 231b and 232b are overlapped.

  Thus, according to the form provided with the hinge 276 that connects each member of the bracket 202A configured to be dividable in the circumferential direction, the mounting portion by the bolt nut 234A is reduced, so the bracket 202A is attached to the column main body 102. Easy to install.

<Buffer material 278>
Further, as shown in FIG. 7, a cushioning material 278 may be attached to the attachment portion of the bracket 202 </ b> A (here, the inner periphery of the insertion hole 227 </ b> A of the boss portion 226 </ b> A). By attaching the cushioning material 278, it is possible to prevent the column main body 102 from being damaged. For example, the cushioning material 278 may be formed of a rubber sheet having a required strength. By adopting an appropriate rubber for the buffer material 278, it is possible to suppress the sliding between the bracket 202A and the column main body 102, and to prevent the bracket 202A from being displaced from the column main body 102.

  Also, a plurality of rubbers 204 may be arranged as described above. In this case, the rubber 204 may be disposed along a concentric circle C with respect to the axis of the support column 100 to which the bracket 202 is attached, as shown in FIG.

  8 and 9 show a column 100B and a column vibration damping device 200B according to another embodiment. As shown in FIGS. 8 and 9, the strut damping device 200 </ b> B includes four independent damping units (1) to (4). Each damping part (1) to (4) includes a flange 224B (bracket 202B), rubber 204B, and a weight 206B.

  Here, the flange 224B is a single piece that extends so as to project in the radial direction of the column main body 102B. In this embodiment, the flange 224B is welded to the outer peripheral surface of the column main body 102B. Further, the four flange portions 224B are equally arranged in the circumferential direction of the column main body 102B. Further, in this embodiment, the rubber 204B and the weight 206B are arranged along the concentric circle C with respect to the central axis O of the column main body 102B in each flange portion 224B.

  Thus, the flange portion 224B (bracket 202B) may be fixed (welded in this embodiment) to the column main body 102B. Further, since the rubber 204B and the weight 206B are arranged along the concentric circle C with respect to the central axis O of the column main body 102B, the weight 206B is arranged evenly in the circumferential direction with respect to the column main body 102B. Inertial force acts. Thus, by arranging the rubber 204B and the weight 206B in a well-balanced manner with respect to the column main body 102B, the vibration of the column main body 102B can be smoothly damped.

  In this embodiment, the weights 206B are independent of each other. In this case, immediately after the vibration is applied to the column main body 102B, as shown in FIG. 10, the weight 206B sways in substantially the same direction with respect to the column main body 102B by the inertial force. Since the weights 206B swing independently, the weights 206B may swing in different directions thereafter. At this time, the weight of the weight 206B and the strength (attenuation performance) of the rubber 204B may be varied. As a result, the natural frequencies of the rubber 204B and the weight 206B can be changed. Thereby, it can design so that the vibration of the support | pillar main body 102B may be attenuate | damped earlier. Further, the behavior of the column main body 102B when the vibration is applied can be stabilized.

  Further, in the strut damping device 200B shown in FIGS. 8 and 9, four rubbers 204B and weights 206B are equally arranged in the circumferential direction of the strut body 102B. In this case, the number of rubbers 204B and weights 206B is not limited to four. For example, three, five, or six rubbers 204B and weights 206B may be arranged along the circumferential direction of the column main body 102B. The plurality of rubbers 204B and weights 206B may be evenly arranged in the circumferential direction of the column main body 102B, or may not necessarily be arranged uniformly. Further, the plurality of rubbers 204B and weights 206B may not be arranged along the concentric circle C of the column main body 102B. In addition, by arranging a plurality of rubbers 204B and weights 206B in a well-balanced manner, the behavior of the column main body 102B and the column damping device 200B can be stabilized. For example, the behavior of the column main body 102B and the column damping device 200B can be stabilized by evenly arranging them in the circumferential direction along a concentric circle with respect to the axis of the column main body. For example, the columnar damping device 200B may have a center of gravity disposed on or near the central axis of the columnar body 102B.

  For example, as shown in FIG. 11, in the strut damping device 200B, two rubbers 204B and two weights 206B may be disposed around the strut body 102B. In this case, the rubber 204B and the weight 206B may be disposed at an angle of 90 degrees with respect to the central axis O of the column main body 102B, for example.

  Further, as in the column 100C and the column damping device 200C shown in FIG. 12, the rubber 204C and the weight 206C may be attached to the lower side of the flange portion 224C (bracket 202C). In FIG. 12, reference numeral 102C indicates a support body, reference numeral 222C indicates a mounting portion, reference numeral 226C indicates a boss portion, reference numeral 228C indicates a restraint portion, and reference numeral 234C indicates a bolt and nut.

<Example of rubber 204>
Here, for the rubber 204 described above, for example, a high damping rubber having a loss coefficient tan δ of 0.2 to 1.2 at a shear strain of 3% to 20% may be used. By using such rubber, vibration of the column main body 102 can be effectively suppressed. More preferably, the loss factor tan δ is 0.3 or more at a shear strain of 3% to 20%, and more preferably, the loss factor tan δ is 1.0 or less at a shear strain of 3% to 20%.

  The present inventor created a column 100 to which the above-mentioned column damping device 200 was attached, and verified the effect of the column damping device 200. When a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was evaluated. Specifically, here, vibration (2 Hz in this case) corresponding to the natural vibration of the column main body 102 is applied to the lower part of the column main body 102 by a vibration exciter, and vibration acceleration is performed by an acceleration pickup attached to the upper part of the column main body 102. Was measured. When the vibration acceleration reaches 0.3G, the vibration exciter is stopped, and the acceleration decay time of the upper part of the column (here, the vibration acceleration is 10% or less (1/10 0.03G or less)). Time).

  Table 1 shows the results of such a test.

<Sample 1>
Here, sample 1 is a case where the vibration damping device for the column is not attached, and when a predetermined vibration is applied to the column (column body), the vibration acceleration is 10% or less (1/10 0.03G). The time to converge to) was 300 seconds. Here, in the column main body 102, the height h1 of the upright portion 121 is 10 m, the base diameter (outer diameter) is 150 mm, and the taper is about 1/100 taper (the diameter is 1 mm smaller than the height of 100 mm). ) And a hollow steel pipe having a thickness of 5 mm (see FIG. 1). The upper end of the column is curved and protrudes to one side in the radial direction, and a street light of about 15 kg is attached. The natural frequency B of the primary vibration mode in the horizontal direction of the column main body 102 was 2.0 Hz. Similar strut bodies 102 were used for samples 2 to 8 in Table 1.

<Natural frequency B of prop body 102>
Here, for example, an acceleration pickup (acceleration sensor) is attached to the upper portion of the support body 102, and the support body 102 is hit with an impact hammer in the vicinity of the acceleration pickup. At that time, the natural frequency B of the column main body 102 is obtained by Fourier transforming the vibration acceleration measured by the acceleration pickup. However, the natural frequency B of the column main body 102 may be obtained by the following mathematical formula (Formula 1).

<Sample 2>
In Sample 2, as shown in FIG. 2, a column vibration damping device 200 using an annular weight is attached to the upper part (approximately 10 m position: h <b> 1) of the upright portion 121 of the column main body 102. Here, the bracket 202 of the strut damping device 200 includes a substantially disk-shaped flange portion 224 having a diameter of 300 mm. In addition, the rubber 204 of the vibration damping device 200 for a pillar has a cylindrical shape with a natural length of 80 mm in diameter and 40 mm in height. Four rubbers 204 were equally attached in the circumferential direction so that the centers were arranged on a concentric circle having a radius of 125 mm from the center of the substantially disc-shaped flange portion 224 (the column main body 102). A cylindrical weight 206 having an outer diameter (diameter) of 300 mm and an inner diameter (diameter) of 200 mm was used. The weight 206 is concentric with the circle on which the rubber 204 is disposed, and is attached to the upper end of the rubber 204. Note that the weight of the weight 206 differs depending on the sample. Here, the weight 206 is made of the same material, and the weight is adjusted by the thickness (height) of the weight 206.

<The natural frequency A of the vibration control device 200 for the column>
Here, for example, the bracket 202 of the strut damping device 200 is fixed to a base, and an acceleration pickup (acceleration sensor) is attached to the weight 206. Then, the weight 206 is hit with an impact hammer. At this time, the natural frequency A of the strut damping device 200 can be obtained by Fourier transforming the vibration acceleration measured by the acceleration pickup attached to the weight 206.

  In sample 2, a high attenuation rubber (high attenuation rubber 2) having a loss coefficient tan δ of 0.25 at a shear strain of 3% to 20% was used as the rubber 204, and the weight of the weight 206 was set to 12 kg. The natural frequency of the strut damping device 200 was approximately 2.0 Hz (approximately 1.0 times the natural frequency of the strut body). In Sample 2, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 45 seconds. As described above, in Sample 2, the time until the vibration converges is about 3/20 compared to Sample 1 in which the vibration damping device 200 for the column is not attached.

<Sample 3>
Sample 3 was configured in the same manner as Sample 2 except that high-damping rubber (high-damping rubber 1) having a loss coefficient tan δ of 0.35 at a shear strain of 3% to 20% was used as rubber 204. In Sample 3, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 10 seconds. Thus, in sample 3, the time until the vibration converges is about 1/30 compared to sample 1 in which the vibration damping device 200 for a column is not attached.

<Sample 4>
The sample 4 was configured in the same manner as the sample 3 except that the strut damping device 200 was attached to an intermediate portion (position of about 5 m: h2) of the upright portion 121 of the strut body 102. In Sample 4, when a predetermined vibration was applied to the support (support main body), the time until the amplitude converged to 10% or less was 25 seconds. Thus, compared with the sample 1 which does not attach the support | pillar damping device 200, time until a vibration converges became about 1/12.

<Sample 5>
Sample 5 was configured in the same manner as Sample 3 except that it was attached to the lower part of the upright part 121 of the column main body 102 (position about 50 cm: h5). In sample 5, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 45 seconds. As described above, the time until the vibration converges is about 3/20 as compared with the sample 1 in which the strut damping device 200 is not attached.

<Sample 6>
In sample 6, the weight 206 was reduced to 3.0 kg, and the natural frequency of the vibration damping device 200 for the column was 2.6 Hz (approximately 1.3 times the natural frequency of the column main body). The configuration was the same as Sample 3. In this case, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 30 seconds. Thus, even when the weight 206 is lightened and the natural frequency of the strut damping device 200 is increased, the time until the vibration converges is about 1 / compared to Sample 1 in which the strut damping device 200 is not attached. It became ten.

<Sample 7>
Sample 7 was configured in the same manner as Sample 6, except that the natural frequency of the strut damping device 200 was set to 3.0 Hz (approximately 1.5 times the natural frequency of the strut body). In this case, when a predetermined vibration is applied to the support (the support main body), the time until the amplitude converges to 10% or less is 50 seconds. Compared to Sample 1 in which the support damping device 200 is not attached, The time until the vibration converges is about 1/6.

<Sample 8>
As shown in FIGS. 8 and 9, the sample 8 used a strut damping device 200 </ b> B in which a plurality of independent weights 206 </ b> B were attached. Here, as shown in FIG. 9, four weights 206 </ b> B are equally arranged in the circumferential direction, and the total weight of the weights 206 </ b> B is set to 12 kg as in the sample 3. Further, high damping rubber having a loss factor tan δ of 0.35 at a shear strain of 3% to 20% was used for the rubber 204B, and the natural frequency of the strut damping device 200B was set to about 2.0 Hz. In Sample 8, the support vibration damping device 200B is attached to the upper part of the upright portion 121 of the support body 102. As a result, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 10 seconds. As described above, also for the strut damping device 200B to which a plurality of independent weights 206B are attached, a favorable result was obtained for converging the vibration of the strut body 102 at an early stage.

  In the sample 8, as shown in FIGS. 8 and 9, four flange portions 224B extending radially outward from the column main body 102 are equally arranged in the circumferential direction. The rubber 204B of the support vibration damping device 200B has a cylindrical shape with a natural length of 80 mm in diameter and 40 mm in height. The rubber 204B is attached on each of the four flange portions 224B. The rubber 204B is attached so that the center is arranged on a concentric circle having a radius of 125 mm from the center of the column main body 102. The weight 206B is attached to the upper end of the rubber 204B.

<The natural frequency A of the vibration damping device 200B for the column>
Here, the natural frequency A of the strut vibration damping device 200B shown in FIGS. 8 and 9 is a set of vibration damping parts (1) to (1) composed of the rubber 204B, the weight 206B, and the flange part 224B. A plurality (4 in the illustrated example) of (4) are attached. In this case, the natural frequency may be obtained for each of the damping parts (1) to (4) constituted by the rubber 204B, the weight 206B, and the flange part 224B. As for the natural frequencies of the vibration control units (1) to (4), the bracket 202B of the support vibration control device 200B is fixed to a base, and an acceleration pickup (acceleration sensor) is attached to each weight 206B. Then, each weight 206B is hit with an impact hammer. At this time, the natural frequency A of the strut damping device 200B can be obtained by Fourier transforming the vibration acceleration measured by the acceleration pickup attached to each weight 206B. In addition, in each damping part (1) to (4), when the configurations of the rubber 204B, the weight 206B, and the flange part 224B are substantially the same, the natural frequency of each damping part (1) to (4). A may be approximately the same.

  In Sample 8, four sets of vibration damping devices including rubber 204B, weight 206B, and flange portion 224B are attached around the column main body 102B in the upper part of the column main body 102B. The loss factor tan δ, the weight of the weight 206, the natural frequency Ao (of each damping part (1) to (4)) in the shear strain 3% to 20% of the rubber 204B of each damping part (1) to (4). Hz) is as shown in Table 2. In this case, the natural frequency Ao of each of the damping units (1) to (4) is 2.0, and the natural frequency A of the entire strut damping device 200B is set to 2.0.

  In addition, when the natural frequencies Ao (Hz) of the vibration damping units (1) to (4) are different, the strut vibration damping device 200B as a whole is unique to the vibration damping units (1) to (4). It has a plurality of natural frequencies A corresponding to the frequency Ao (Hz). For example, if the natural frequencies Ao (Hz) of the vibration damping units (1) to (4) are 1.2, 1.5, 1.7, and 2.0, respectively, the strut damping device 200B is applied. It has four natural frequencies. In such a case, the natural frequency A of the strut damping part (the strut damping device 200, 200B) and the strut body 102 in a state where the members constituting the strut damping part are not attached. Four ratios (A / B) with the frequency B are generated.

<Sample 9>
Sample 9 was configured in the same manner as Sample 3 except that high-damping rubber (high-damping rubber 3) having a loss coefficient tan δ of 1.1 at a shear strain of 3% to 20% was used as rubber 204. In this case, when a predetermined vibration is applied to the column (column body), the time until the amplitude converges to 10% or less is 50 seconds, and the vibration is converged by attaching the column damping device 200. The time to do is about 1/6.

<Sample 10>
Sample 10 is sample 3 except that weight 206 is heavier than 24 kg, and the natural frequency of strut damping device 200 is 1.4 Hz (approximately 0.7 times the natural frequency of the strut body). It was configured in the same way. In this case, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 30 seconds. Even when the weight 206 is made heavier and the natural frequency of the strut damping device 200 is lowered, the time until the vibration converges becomes about 1/10 by attaching the strut damping device 200. It was.

<Sample 11>
The sample 11 is a sample except that the weight 206 is further increased to 36 kg and the natural frequency of the vibration damping device 200 for the column is 1.0 Hz (approximately 0.5 times the natural frequency of the column main body). 3 was configured. In this case, when a predetermined vibration was applied to the column (column body), the time until the amplitude converged to 10% or less was 50 seconds. In this way, even when the weight 206 is further increased and the natural frequency of the support vibration damping device 200 is further lowered, the time until the vibration converges is reduced by about 1/6 by attaching the support vibration damping device 200. Became.

  Here, as the molded body 204 of high damping rubber, high damping rubber 1 using natural rubber as a base rubber (loss factor tan δ: 0.35 at a shear strain of 3% to 20%) and high damping using EPDM as a base rubber. Rubber 2 (0.25) and high damping rubber 3 (1.1) using natural rubber as a base rubber were used. Table 3 shows the composition of the high damping rubber 1, the high damping rubber 2 and the high damping rubber 3. Here, in addition to the base rubber, silica powder, process oil, vulcanized material (sulfur), and vulcanization accelerator were used as additives. When silica is blended with rubber, process oil is necessary, and the process oil is preferably used in about 1/3 by weight ratio of silica. In Table 3, the addition amount of each additive indicates the addition amount with respect to 100 parts by weight of natural rubber or EPDM as the base rubber.

  Here, Esplen 301A manufactured by Sumitomo Chemical Co., Ltd. was used for EPDM. As the silica powder, Aerosil R972 manufactured by Nippon Aerosil Co., Ltd. was used. Moreover, Diana process oil NS of Idemitsu Kosan Co., Ltd. was used for the process oil. As the vulcanization accelerator 1, Noxeller DZ manufactured by Ouchi Shinsei Chemical Co., Ltd. was used. Further, Noxeller TS of Ouchi Shinsei Chemical Co., Ltd. was used as the vulcanization accelerator 2.

  The rubbers 204 and 204B preferably have a loss coefficient tan δ of about 0.2 or more and 1.2 or less at a shear strain of 3% to 20%. The loss factor tan δ is more preferably 0.25 or more, and further preferably 0.3 or more. The loss coefficient tan δ is more preferably 1.1 or less, and further preferably 1.0 or less. Thereby, the vibration which arises in a support | pillar main body can be attenuated earlier.

  Further, the propulsion damping portion (the strut damping device 200, 200B) that includes the flange portions 224, 224B (bracket 202, bracket 202B), rubber 204, 204B, and weights 206, 206B. The ratio (A / B) between the frequency A and the natural frequency B of the column main body 102 in a state where the member constituting the column damping portion is not attached is approximately 0.5 ≦ (A / B) ≦. It is good that it is 1.5. The natural frequency ratio (A / B) is preferably 0.7 ≦ (A / B), more preferably 0.80 ≦ (A / B), and still more preferably 0.90 ≦ (A / B). B). Further, it is preferable that (A / B) ≦ 1.30, more preferably (A / B) ≦ 1.20, and still more preferably (A / B) ≦ 1.10. Thereby, the vibration which arises in a support | pillar main body can be attenuated earlier.

  Further, like the strut damping device 200B shown in FIG. 8 and FIG. 9, the strut damping device 200B has a plurality of damping parts (1) to (4), and each damping part ( When 1) to (4) have different natural frequencies, the strut damping device 200B shows a plurality of natural frequencies. At this time, a plurality of the ratios (A / B) are generated. In this case, at least one of the plurality of ratios (A / B) may be in the above range. Thereby, the effect which attenuates the vibration which arises in a support | pillar main body at an early stage can be anticipated.

  Further, the flange portion 224 (bracket 202) of the support vibration damping device 200 may be attached to a position that is half the height of the support body 102 or a position that is higher than half the height of the support body 102. Thereby, the vibration which arises in a support | pillar main body can be attenuated at an early stage, and the support | pillar damping device 200 can be functioned more effectively.

  As mentioned above, although the support | pillar and the vibration damping device for support | pillar which concern on one Embodiment of this invention were demonstrated, this invention is not limited to embodiment mentioned above.

  For example, in the above-described embodiment, the post for road signs is illustrated, but the post and the vibration damping device for post according to the present invention are not limited to the use for road signs, for example, an antenna post or a flag. Applicable to various struts such as standing struts.

100, 100B, 100C Prop 102, 102B, 102C Prop body 104 Street lamp 121 Upright part 122 Overhang part 123 Tip part 200, 200A, 200B, 200C Vibration control device 202, 202A, 202B, 202C Bracket 204, 204B, 204C Rubber 206, 206B, 206C Weight 222 Mounting portion 224, 224A, 224B, 224C Flange (flange)
226, 226A, 226C Boss part 227, 227A Insertion hole 228, 228A, 228C Restriction part 231, 231a, 231b Alignment piece 232, 232a, 232b Alignment piece 234, 234A Bolt nut 236 Connecting member 237 Dividing surface 238, 239 Constraint plate 252 Mounting plate (mounting member)
254 Mounting plate (Mounting member)
262 Adjustment weight 270 Sliding bearing 276 Hinge 278 Shock absorber 300 Installed part C Concentric circle O Center axis

Claims (22)

A bracket having a mounting portion attached to the column and a flange portion extending radially outward from the mounting portion;
Rubber attached to the top or bottom of the flange portion;
A vibration damping device for a column, comprising a weight attached to the rubber on the side opposite to the flange portion.   The strut damping device according to claim 1, wherein the weight is replaceable.   The strut damping device according to claim 1 or 2, wherein the rubber is replaceable.   The said bracket is a vibration suppression apparatus for pillars as described in any one of Claim 1 to 3 which is a ring-shaped member attached to the surrounding side surface of the pillar to which the said bracket is attached.   The said bracket is a support | pillar damping device of Claim 4 provided with the restraint member which restrains a bracket in the state which can be divided | segmented into the circumferential direction and was attached to the surrounding side surface of a support | pillar.   The said bracket was a vibration damping device for pillars described in Claim 5 provided with the hinge which connects the member divided | segmented into the circumferential direction.   The strut damping device according to any one of claims 1 to 6, wherein a plurality of the rubber and the weight are respectively arranged.   The strut damping device according to claim 7, wherein the rubber and the weight are arranged along a concentric circle with respect to an axis of a strut to which the bracket is attached.   The weight is an annular member, and the rubber supports the weight at a plurality of positions in a circumferential direction with respect to a column to which the bracket is attached. Damping device for prop.   The rubber and the weight are attached to the upper side of the flange portion, and provided with a sliding bearing that supports the weight between the weight and the flange portion. The vibration control device for the described support.   The strut control according to any one of claims 1 to 10, wherein the rubber is a high-damping rubber having a loss coefficient tan δ of 0.2 to 1.2 at a shear strain of 3% to 20%. Shaker. A column main body standing on the installation part;
A flange attached to the column body and extending radially outward from the column body;
Rubber attached to the top or bottom of the flange;
A strut comprising a weight attached to the rubber on the opposite side of the flange.   13. A strut according to claim 12, wherein the weight is replaceable.   The strut according to claim 12 or 13, wherein the rubber is replaceable.   The column according to any one of claims 12 to 14, wherein the flange is a ring-shaped member continuous in the circumferential direction of the column main body.   The strut according to any one of claims 12 to 15, wherein a plurality of the rubber and the weight are respectively disposed along a circumferential direction of the strut body.   The strut according to claim 16, wherein the rubber and the weight are disposed along a concentric circle with respect to an axis of the strut body.   The pillar according to any one of claims 12 to 15, wherein the weight is an annular member, and the rubber supports the weight at a plurality of circumferential positions with respect to the pillar body. .   The rubber and the weight are attached to the upper side of the flange, and include a sliding bearing that supports the weight between the weight and the flange. Prop.   20. The strut according to claim 12, wherein the flange is attached at a position that is half the height of the strut body or a position that is higher than half the height of the strut body.   The strut according to any one of claims 12 to 20, wherein the rubber is a high-damping rubber having a loss coefficient tan δ of 0.2 to 1.2 at a shear strain of 3% to 20%.   The natural frequency A of the strut damping part composed of the flange, the rubber, and the weight, and the uniqueness of the strut body in a state in which the member constituting the strut damping part is not attached The support column according to any one of claims 12 to 21, wherein a ratio (A / B) to the frequency B is 0.5 ≦ (A / B) ≦ 1.5.

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