JP2531295Y2 - Handrail noise prevention device - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a handrail of a balcony of a house, and more particularly to a device for preventing the handrail of a balcony from making noise due to wind. is there.

2. Description of the Related Art A handrail is provided on a balcony of a house to prevent people from falling and to further improve the appearance. Such a handrail is
It is usually exposed to the wind and rain, and depending on the weather conditions, the handrail may generate noise.

The noise of the handrail is generated when the lattice constituting the handrail resonates with the wind.

That is, when the wind passes through the lattice, Karman vortices are generated behind the lattice, and when the frequency of the Karman vortices matches the natural frequency of the lattice, the lattice resonates to generate noise.

Here, the natural frequency f _o of the lattice is f _o = (√ / √) / (2π) ... k: spring constant of the lattice determined by the elastic modulus and the second moment of area m: mass of the lattice frequency f _w of the Karman _{vortex, f w = S t × V} / D ... S t: Strouhal number V: wind D: represented by the diameter of the surface of the grating wind strikes.

Therefore, with respect to the expected wind speed, such conditions do not resonate with the lattice, namely may do it to give a f _o ≠ f _w. However,
The handrail specifications and the shape of the grid are almost uniquely determined from the design of the installation conditions.There is a limit to the conditions that do not resonate with the grid when manufacturing the grid and when installing the handrail. Is almost impossible. Conventionally, when noise occurs after the handrail is installed, sand is filled in the inside of the lattice to change the mass in the vibration system and suppress resonance.

[Problem to be Solved by the Invention] Conventionally, the cross-sectional shape of the lattice was devised at the time of producing the lattice, but as described above, it is not a sufficient measure, and noise occurs depending on the installation conditions of the handrail. That was inevitable. Therefore, although one grid was filled with sand as a countermeasure in the case of occurrence of noise, the workability was very poor, and a measure capable of effectively preventing noise was demanded.

The present invention has been made in view of the above circumstances, and aims to provide a noise prevention device that can easily and effectively prevent a noise when a noise occurs or when a noise is expected. It is.

[Means for Solving the Problems] The present invention relates to a handrail composed of opposing frames and a plurality of hollow grids provided between the frames, the weight being movable inside the grids. And the weight is fixed at a required position excluding both ends.

[Function] By inserting a weight into the lattice, the mass in the lattice vibration system can be changed and the natural frequency can be changed. The natural frequency of the lattice vibration system can be changed to the frequency f _{w of the} Karman vortex generated by wind. Therefore, the resonance can be prevented and the noise of the balcony handrail can be prevented.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 7, the handrail 1 includes a lower frame 2 and the lower frame 2.
The upper frame 3 is connected to the upper frame 3 at a required pitch by a grid 4. The lower end of the grid 4 and the lower frame 3, and the upper end of the grid 4 and the upper frame 3 are respectively tapped. They are connected by bolts 5.

 The details will be described below with reference to FIGS.

The lattice 4 has a required cross-sectional shape (a hexagonal shape in this embodiment) according to the lattice design, and is hollow.

Also, ridges facing the longitudinal direction are provided inside the lattice 4.
6 and 7 are formed, and a round groove 8 is formed by the two ridges 6 and 7. The tapping bolt 5 is screwed into the round groove 8.

Before the grid 4 is fixed to the upper and lower frames, a weight 9 is fitted into the grid 4. The weight 9 has a shape that substantially closes a hollow portion inside the lattice, and has a relief groove 10 so as not to buffer the ridges 6 and 7 and can slide freely.

After the weight 9 has been fitted, the required position (effectively the grid 4
Center).

Next, a weight stopper 11 formed by bending an elastic wire such as a stainless steel wire or a rust-proofed piano wire in a circular shape, and further bending both ends so as to expand the hem into a substantially Ω shape, is formed into a circular shape. The round groove 8 is fitted with the bent portion at the tip and in a state where the width is narrowed, and the round groove 8 is pushed as a guide until it comes into contact with one end surface of the weight 9. The weight stoppers 11 are fitted from both ends of the lattice 4, and hold the weight 9 between the two weight stoppers 11. The weight stopper 11 has elasticity at both ends of the grid 4
Since the weight stopper 11 is pressed against the inner surface, the retraction of the weight stopper 11 is suppressed. That is, the weight 9 is held at the set position by being sandwiched between the two weight stoppers 11. As shown in the above equation, by changing the mass m on the lattice side, the natural frequency f _o of the lattice becomes the frequency of the Karman vortex generated by the wind.
inevitable that it matches the f _w, sound Nari can be prevented.

Further, the weight of the weight 9 can be easily changed by changing the length of the weight in the axial center direction or by using a plurality of weights having a unit length. Weight.

Also, the weight 9 can be attached only by inserting the weight and pushing the weight stopper 11, and the operation is extremely simple. Attachment of the weight 9 may be performed at the factory before shipment.
Alternatively, it may be performed when noise occurs after installation.

Further, since the apparent mass changes from the position of the weight, it is possible to prevent noise even by adjusting the position of the weight.

 Furthermore, various shapes and fixing methods of the weight can be considered.

FIG. 5 shows a case where the weight 12 is formed in a cylindrical shape, a screw is engraved around the weight, and the weight 12 is screwed.

FIG. 6 shows a configuration in which a concave portion 15 is formed in the weight 13, a leaf spring 14 is attached to the concave portion 15, and the weight 13 is fixed by the leaf spring 14. In this embodiment, two weights 13 are screwed in symmetrically from both ends of the lattice 4 until the two weights 13 abut.

Further, although not particularly shown, a resin which is an elastic body may be fixed to the weight, the weight may be press-fitted, and the weight may be fixed inside the lattice by the elastic force of the resin, or a shape memory resin may be used. Needless to say, the handrail may be fixed or fixed with an adhesive, and it goes without saying that the present invention can be applied to a handrail having a similar structure such as a handrail of a staircase in a house.

[Effects of the Invention] As described above, according to the present invention, it is possible to easily prevent noise with a simple structure and extremely simple work.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of the present invention, and FIG.
FIG. 3 is a view taken along arrow AA of FIG. 3, FIG. 3 is a view taken along arrow BB of FIG. 1, FIG. 4 is a view taken along arrow CC of FIG. 1, and FIG. FIG. 6 is a partial sectional view showing still another embodiment, and FIG. 7 is an overall view of a handrail. 1 is a balcony handrail, 2 is a lower frame, 3 is an upper frame, 4 is a lattice,
9 denotes a weight, and 11 denotes a weight stopper.

Claims (2)

(57) [Scope of request for utility model registration] In a handrail comprising a frame facing each other and a plurality of hollow grids provided between the frames, a movable weight is fitted into the grid, and the weight is attached to both ends. A handrail noise prevention device, which is fixed at a required position except for a handrail. 2. The sound of a handrail according to claim 1, wherein weight stoppers each formed by bending an elastic wire into a substantially Ω shape are inserted from both ends of the lattice, and the weights fitted into the lattice are clamped and fixed by the weight stoppers. Prevention device.