JP2014031695A - Vibration-suppressing suspension structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress cumulative plastic deformation of hanging bolts while increasing the degree of freedom of installation by dispensing with a brace between the hanging bolts, in a vibrational energy-absorbing suspension structure reducing vibrations of suspension equipment suspended from a ceiling slab by the hanging bolts.SOLUTION: A connector 15, in which upper and lower brackets 16 and 17 are combined together, is provided at a ceiling slab-side base end of a hanging bolt. A steel ball 18, which is sandwiched between locking surfaces 16a and 17a of the upper and lower brackets 16 and 17 to bear a load of suspension equipment and which makes the upper and lower brackets 16 and 17 relatively displaceable in a horizontal direction, is interposed between the upper and lower brackets 16 and 17 of the connector 15.

Description

  The present invention relates to a vibration-suppressing suspension structure that reduces the vibration of suspension equipment suspended from a ceiling slab with suspension bolts.

  Conventionally, a suspension equipment device suspended from a ceiling slab with a suspension bolt may fall due to a large earthquake or the like. When the cause is examined, stress concentrates at the base of the suspension bolt (base end, upper end fixed to the ceiling slab), and plastic deformation accumulates after the base yields, and the suspension bolt root may break. all right. In order to prevent such breakage of the suspension bolt, a brace is provided between one base of the pair of suspension bolts and the other end portion (lower end portion fixed to the suspension equipment), and deformation of each suspension bolt (For example, refer to Patent Document 1).

JP 2008-208687 A

  As described above, if the brace and other steady rest materials are provided, the deformation of the suspension bolt can be drastically suppressed. For example, when placing the suspension equipment across the beam, it is difficult to provide the brace There is.

  The present invention has been made in view of the above-described problems, and in a vibration-suppressing suspension structure that reduces vibrations of suspension equipment suspended from a ceiling slab with suspension bolts, the bracing between the suspension bolts is eliminated and the installation is free. It is an object to suppress deformation of the suspension bolt after increasing the degree.

  As a means for solving the above problem, the invention described in claim 1 is a vibration suppressing suspension structure for reducing vibration of a suspension facility device suspended from a ceiling slab with a suspension bolt, wherein An end is provided with a connector for suspending a bolt body fixed to the suspension equipment, and the connector is fixed to the ceiling slab and forms an upward locking surface; and the bolt body A lower bracket that is fixed and forms a downward locking surface that engages the upward locking surface from above, and is sandwiched between the upward locking surface and the downward locking surface so that the upper and lower brackets can move relative to each other. And rolling elements.

According to this configuration, even if the suspension equipment vibrates due to an earthquake or the like, the transmission of the vibration can be suppressed by the relative movement between the upper and lower brackets at the base end portion of the suspension bolt, and the bending acts on the base end portion of the suspension bolt. The moment can be reduced and the deformation of the base end of the suspension bolt can be reduced.
Moreover, compared with the case where a brace is provided between a plurality of suspension bolts, the degree of freedom of installation is high even when the suspension equipment is disposed across the beam, and vibration measures can be easily implemented.

  In the present invention, if the connector has an energy absorber that is attached to one of the upper and lower brackets and abuts the other of the upper and lower brackets during the relative movement, the relative movement of the upper and lower brackets until they abut each other. The amount can be secured, and the vibration energy of the suspension equipment can be absorbed by abutting against the energy absorber. The energy absorber may be an elastic body such as synthetic rubber or a damping material such as a friction damper.

In the present invention, at least one of the upward locking surface and the downward locking surface is formed with a concave portion that has an arc-shaped cross section having a diameter larger than that of the rolling element and partially enters the rolling element. If there is, the rolling element can be held at a predetermined position between both locking surfaces while reducing the rolling resistance of the rolling element.
In the present invention, the lower bracket can be stably supported on the upper bracket by supporting at least three points by a plurality of rolling elements, provided that the rolling elements are arranged at least at three locations arranged in a triangular shape in plan view. .

In the present invention, if the bolt dynamic energy absorber is interposed between the bolt main body and the bolt main body in the lower bracket, the bolt main body moves relative to the lower bracket. The vibration energy of the suspension equipment can be absorbed while allowing by the bending of the bolt dynamic energy absorber.
In the present invention, if the upper and lower brackets have a configuration in which the upper and lower brackets are turned upside down, the cost can be reduced by sharing the parts.

  According to the present invention, in a vibration-suppressing suspension structure that reduces vibrations of suspension equipment suspended from a ceiling slab with suspension bolts, deformation of the suspension bolts is achieved while eliminating the bracing between the suspension bolts and increasing the degree of freedom of installation. Can be suppressed.

It is a front view of the vibration suppression suspension structure in the embodiment of the present invention. It is II-II sectional drawing of FIG. It is a perspective view of the coupling tool of the suspension bolt of the said vibration suppression suspension structure. It is a front view containing the partial cross section of the said coupling tool. It is VV sectional drawing of FIG. It is a front view equivalent to FIG. 4 which shows the effect | action with respect to the horizontal motion of the said connector. It is a front view equivalent to FIG. 4 which shows the effect | action with respect to the motion of the said connector in the perpendicular direction.

Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIGS. 1 and 2, the vibration suppression suspension structure 1 of the present embodiment has a configuration in which suspension equipment 7 such as an air conditioning equipment is suspended from a plurality of (four) suspension bolts 5 on a ceiling slab 2 of a building. Have The hanging equipment 7 has a rectangular parallelepiped shape, for example, and is arranged with its upper surface 8 substantially horizontal. A substantially horizontal flange 9 is provided on the outer periphery of the upper surface 8, for example, over the entire periphery. The lower end portions (tip portions) of the suspension bolts 5 extending in the vertical direction are fastened and fixed to the flanges 9 at the four corners of the suspension equipment device 7 in plan view (top view). Reference numerals 11 and 12 in the drawing denote upper and lower nuts that are screwed to the lower end portion of the suspension bolt 5 and tightened with the flange 9 interposed therebetween. The suspended equipment 7 is arranged to be spaced downward from the lower surface 3 of the ceiling slab 2, and even if there is a beam 4 projecting downward from the lower surface 3 of the ceiling slab 2, it can be arranged below that.

  In the vibration suppression suspension structure 1, a total of four suspension bolts 5 positioned at the four corners of the rectangular shape in plan view of the suspension equipment 7 are provided with a connector 15 in which upper and lower brackets 16 and 17 are combined at each base end portion. . Each suspension bolt 5 includes an anchor bolt 13 fixed to the ceiling slab 2, a connector 15 attached to the anchor bolt 13, and a bolt body 14 suspended from the connector 15.

  As shown in FIGS. 3 and 4, the connector 15 includes an upper bracket 16 fixed to the anchor bolt 13, a lower bracket 17 fixed to the upper end portion of the bolt body 14, and an upward locking formed by the upper bracket 16. And a plurality of steel balls 18 sandwiched between a downward locking surface 17a formed by the surface 16a and the lower bracket 17. The connector 15 locks the lower bracket 17 to the upper bracket 16 via a plurality of steel balls (rolling elements) 18, and connects the upper and lower brackets 16, 17 along both parallel and horizontal locking surfaces 16 a, 17 a. It is possible to move relative to each other.

  The upper bracket 16 is formed by integrally joining a plurality of steel materials by welding or fasteners. The upper bracket 16 is disposed substantially horizontally and allows the anchor bolt 13 to pass therethrough and is fixed to the anchor bolt 13 by a nut 27 and downward from both side ends of the first plate portion 21. A pair of standing plate portions 23 extending and a rectangular second plate portion 24 extending substantially horizontally across the lower ends of the pair of standing plate portions 23 are provided.

Similarly to the upper bracket 16, the lower bracket 17 is formed by integrally joining a plurality of steel materials by welding or fasteners. The lower bracket 17 has a configuration in which the same configuration as that of the upper bracket 16 is turned upside down.
That is, the lower bracket 17 is disposed substantially horizontally and penetrates the upper end portion of the bolt main body 14, and the rectangular first plate portion 21 that locks the upper end portion with the nut 27 and the bolt kinetic energy absorber 28; The first plate portion 21 includes a pair of standing plate portions 23 extending upward from both side ends, and a rectangular second plate portion 24 extending substantially horizontally between the upper ends of the pair of standing plate portions 23.

  The lower bracket 17 has a reinforcing pipe 14a that is inserted through the bolt body 14 so as to be movable up and down. The reinforcing pipe 14 a is made of a steel pipe and extends from the first plate portion 21 of the lower bracket 17 to the vicinity of the lower end portion of the bolt body 14. The reinforcement pipe 14a reinforces the bending of the long bolt body 14. The upper end portion of the reinforcing pipe 14a passes through the first plate portion 21 of the lower bracket 17 and protrudes upward. The nut 27 and the bolt dynamic energy absorber 28 are locked to the upper end of the reinforcing pipe 14a.

  Referring also to FIG. 5, the lower bracket 17 is disposed so as to be substantially perpendicular to the upper bracket 16 in a plan view (corresponding to the axial view of the suspension bolt 5). The second plate portion 24 of the lower bracket 17 is disposed so as to overlap the second plate portion 24 of the upper bracket 16 from above. The upper and lower brackets 16 and 17 each have a loop shape when viewed from the side, and are connected to each other in a chain shape.

  Between the horizontal upper surface (upward locking surface 16a) of the second plate portion 24 of the upper bracket 16 and the horizontal lower surface (downward locking surface 17a) of the second plate portion 24 of the lower bracket 17 is seen in a plan view. Thus, for example, six steel balls 18 arranged so as to surround the periphery of the bolt body 14 at equal intervals are sandwiched.

  In the present embodiment, a concave portion 19 having an arc-shaped cross section having a larger diameter than the outer diameter of the steel ball 18 is formed on the upper surface (upward locking surface 16 a) of the second plate portion 24 of the upper bracket 16. A plurality of recesses are provided corresponding to Each steel ball 18 has its upper end brought into contact with the lower surface (downward locking surface 17 a) of the second plate portion 24 of the lower bracket 17 in a state where the lower portion is inserted into the corresponding recess 19. In this state, both locking surfaces 16a and 17a are separated from each other. When the suspension equipment 7 vibrates due to an earthquake or the like, each steel ball 18 allows relative movement in all directions along the locking surfaces 16a and 17a between the upper and lower brackets 16 and 17 by its own rolling. The transmission of the vibration to the base end portion of the suspension bolt 5 is suppressed. Each steel ball 18 can be rolled with a small frictional resistance by being held in the recess 19.

  The upper end portion of the bolt body 14 includes a nut 27 screwed over the first plate portion 21 of the lower bracket 17 and a bolt kinetic energy absorber 28 sandwiched between the nut 27 and the upper end of the reinforcing pipe 14a. Thus, the first plate portion 21 of the lower bracket 17 is locked. The bolt dynamic energy absorber 28 is made of an elastic body such as an elastomer, and has a cylindrical shape that has an outer diameter corresponding to a washer of the nut 27 and is inserted through the bolt body 14. As shown in FIG. 7, the upper end portion of the bolt main body 14 is movable upward with respect to the lower bracket 17, and can be moved downward and inclined by the amount of bending of the bolt kinetic energy absorber 28. .

  Thereby, even if the suspension equipment 7 vibrates due to an earthquake or the like, this vibration is directly transmitted to the bolt body 14, but the transmission of the vibration to the lower bracket 17 is suppressed. Although the bolt dynamic energy absorber 28 receives the load of the suspension equipment 7, the bolt dynamic energy absorber 28 is compressed rather than pulled between the bolt main body 14 and the lower bracket 17, so there is no risk of cutting and high reliability.

  As shown in FIG. 5, on the opposite sides of the second plate 24 of the upper and lower brackets 16, 17, the other second plate 24 is moved relatively along the locking surfaces 16 a, 17 a. The plate-shaped energy absorber 29 is disposed with the space S of the above. The energy absorber 29 is made of an elastic body such as an elastomer, for example, and is fixed to the inside of the standing plate portion 23 by adhesion or the like.

  As shown in FIG. 6, when the energy absorber 29 moves relative to each other by the vibration of the hanging equipment 7 and the upper and lower brackets 16 and 17 move relative to each other and the second plate portion 24 of the other party moves beyond the space S, By abutting the long side part of the moved second plate part 24, a part of the energy of the vibration is absorbed, and the vibration of the hanging equipment 7 is reduced. As described above, the transmission of the vibration to the base end portion of the suspension bolt 5 is also suppressed by the counterpart second plate portion 24 hitting the energy absorber 29 and absorbing the vibration energy. Stress concentration at the end is relaxed.

If each steel ball 18 does not slide with respect to each locking surface 16a, 17a (including the inner surface of the recess 19), it returns to the deepest position of the corresponding recess 19. In this case, the upper and lower brackets 16 and 17 are automatically returned to the initial positions before the relative movement.
The steel balls 18 are arranged at equal intervals around the bolt body 14 in a plan view, and stably hold the lower bracket 17 to the upper bracket 16. The steel balls 18 may be at least at three locations arranged in a triangular shape in plan view.

  A plurality of recesses 19 corresponding to each steel ball 18 are formed on the lower surface (downward engagement surface) of the second plate portion 24 of the lower bracket 17 so that the upper part of each steel ball 18 enters the corresponding recess 19. In such a state, the lower end of each steel ball 18 may be brought into contact with the upper surface (upward locking surface 16a) of the second plate portion 24 of the upper bracket 16. A plurality of recesses 19 corresponding to each steel ball 18 are formed on both the upper surface of the second plate portion 24 of the upper bracket 16 and the lower surface of the second plate portion 24 of the lower bracket 17, and The structure may be such that it enters the corresponding recess 19, and in this case, the effect of returning the upper and lower brackets 16, 17 to the initial position before the relative movement is enhanced.

As described above, the vibration suppression suspension structure 1 according to the above-described embodiment is provided with the connection tool 15 that combines the upper and lower brackets 16 and 17 at the base end of the suspension bolt 5 on the ceiling slab 2 side. A steel ball 18 is interposed between the brackets 16 and 17 so as to be sandwiched between the locking surfaces 16a and 17a to receive the load of the suspension equipment 7 and to move the upper and lower brackets 16 and 17 in a horizontal direction. Thus, even if the suspension equipment 7 vibrates due to an earthquake or the like, the transmission of the vibration can be suppressed by the relative movement between the upper and lower brackets 16 and 17 at the base end portion of the suspension bolt 5, and the base end portion of the suspension bolt 5 can be suppressed. It is possible to reduce the deformation of the base end portion of the suspension bolt 5 by reducing the acting bending moment.
Moreover, compared with the case where a brace is provided between the plurality of suspension bolts 5, even when the suspension equipment 7 is arranged across the beam, the degree of installation freedom is high, and vibration measures can be easily implemented.

  Further, the connecting tool 15 is attached to one of the upper and lower brackets 16 and 17 and has an energy absorber 29 that abuts against the other of the upper and lower brackets 16 and 17 during the relative movement, so that the upper and lower brackets 16 and 17 abut each other. These relative movement amounts can be ensured, and the vibration energy of the suspension equipment 7 can be absorbed by being abutted against the energy absorber 29.

  Further, a bolt kinetic energy absorber 28 is interposed between a portion of the lower bracket 17 through which the upper end portion of the bolt body 14 passes and a nut 27 screwed to the upper end portion of the bolt body 14. The vibration energy of the suspension equipment 7 can be absorbed while allowing the bolt main body 14 to move relative to the bolt 17 by the bolt dynamic energy absorber 28.

In addition, this invention is not restricted to the said embodiment, For example, the rolling element pinched | interposed between the locking surfaces 16a and 17a of the upper and lower brackets 16 and 17 is not restricted to the steel ball 18, and may be a roller or a needle. When the reinforcing pipe 14a is eliminated, a bolt kinetic energy absorber 28 is provided between the upper surface of the first plate portion 21 of the lower bracket 17 and the nut 27 thereabove.
And the structure in the said embodiment is an example of this invention, A various change is possible in the range which does not deviate from the summary of the said invention.

DESCRIPTION OF SYMBOLS 1 Vibration suppression suspension structure 2 Ceiling slab 5 Suspension bolt 7 Suspension equipment 14 Bolt main body 14a Reinforcement pipe (bolt penetration part)
DESCRIPTION OF SYMBOLS 15 Connector 16 Upper bracket 16a Upward locking surface 17 Lower bracket 17a Downward locking surface 18 Steel ball (rolling element)
19 Concave portion 28 Bolt dynamic energy absorber 29 Energy absorber

Claims (6)

In the vibration suppression suspension structure that reduces the vibration of the suspension equipment suspended from the ceiling slab with suspension bolts,
At the base end of the suspension bolt on the ceiling slab side, a connection tool for suspending a bolt main body fixed to the suspension facility equipment is provided.
The connector forms an upper bracket fixed to the ceiling slab and forming an upward locking surface, and a downward locking surface fixed to the bolt body and engaged with the upward locking surface from above. A vibration-suppressing suspension structure comprising: a lower bracket; and a rolling element that is sandwiched between the upward locking surface and the downward locking surface to move the upper and lower brackets relative to each other.   2. The vibration suppression suspension structure according to claim 1, wherein the connector includes an energy absorber that is attached to one of the upper and lower brackets and abuts the other of the upper and lower brackets during the relative movement.   At least one of the upward locking surface and the downward locking surface is formed with a recess having an arc-shaped cross section having a diameter larger than that of the rolling element and partially entering the rolling element. Item 3. The vibration suppression suspension structure according to Item 1 or 2.   The vibration suppressing suspension structure according to any one of claims 1 to 3, wherein the rolling elements are arranged at least in three locations arranged in a triangular shape in plan view.   5. The bolt dynamic energy absorber is interposed between the bolt main body and the bolt main body in the lower bracket, and the bolt main body is interposed between the bolt main body and the bolt main body. Vibration suppression suspension structure.   The vibration suppression suspension structure according to any one of claims 1 to 5, wherein the upper and lower brackets have a configuration in which they are vertically inverted.

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