JP3089970U - Flexible joint - Google Patents

Abstract

(57) [Problem] To provide a flexible joint of a duct for blocking electromagnetic waves contained in exhaust gas passing therethrough. Kind Code: A1 Abstract: In a flexible joint used at a seam arranged to connect two exhaust and ventilation ducts installed in a room or the like, a peripheral wall formed in a cylindrical or quadrilateral form has two insulating walls. A flexible joint comprising a flexible sheet 1 and a duct 1 with angled flanges 5 attached to both ends of a canvas with a mesh-like metal thin film 2 interposed at a predetermined width between the sheets 1 and 1 to intercept electromagnetic waves. .

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a flexible joint to be attached to a joint of an exhaust duct and a ventilation duct used for exhausting indoor air.

[0002]

[Prior art]

 Conventional exhaust and ventilation ducts are provided on the ceiling of cooling and heating equipment, kitchens, medical equipment, and the like, and are formed in a cylindrical shape or a rectangular tube shape. These exhaust and ventilation ducts are generally made of metal materials such as aluminum, stainless steel, and zinc-iron plate. In recent years, electrical products have been widely used in buildings, and the electromagnetic waves generated by these electrical products have passed through the duct together with the exhaust air and are exhausted to the outside through the ventilation openings. The electromagnetic waves and the like contained in the exhaust gas are attenuated while reflecting on the metal surface inside the cylinder of the duct, and are advancing.The electromagnetic waves are externally applied at the joints and gaskets where the metal material of this duct is not used. Was leaking to

[0003]

[Problems to be solved by the invention]

 Thus, the electromagnetic waves in the room are exhausted through the exhaust and ventilation ducts arranged in the room. As non-metallic flexible joints are used as conventional duct joints to prevent earthquakes and measures such as expansion of ducts in summer, such non-metallic flexible joints are not Electromagnetic waves contained in exhaust gas passing through the inside leaked to the outside. In particular, in medical institutions, these electromagnetic waves have a bad effect on diagnostic equipment, test equipment, treatment equipment, and the like, which has been a problem.

[0004] In order to prevent the influence of such electromagnetic waves, there is a flexible joint in which a metal film such as an aluminum foil is bonded to the surface of an elastic joint, but this metal film is electrically conductive. For this reason, static electricity and electric signals propagated through the duct, causing adverse effects. In addition, joints incorporating a film-shaped metal thin film in which metal powder is mixed with synthetic resin to prevent the passage of electromagnetic waves have been proposed, but a metal thin film having a considerable thickness is required to prevent electromagnetic waves. It was required and was not suitable for flexible duct joints due to its weight.

The present invention solves the above-mentioned problems and provides a flexible joint made of a lightweight material that can be used as a joint for a duct that blocks electromagnetic waves. An object of the present invention is to provide an insulated flexible joint which does not leak electromagnetic waves which do not cause electrical disturbance such as static electricity in the surroundings.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention has the following configuration. In a flexible joint used at a seam arranged to connect two exhaust and ventilation ducts installed in a room, etc., the peripheral wall formed around the joint consists of two insulating sheets, The flexible joint has a canvas in which a mesh-like metal thin film for shielding electromagnetic waves is interposed at a predetermined width between the sheets.

The object of the present invention is to provide a method in which a net-like metal thin film that intercepts electromagnetic waves is interposed between the insulating sheets, and a linear portion is formed at the center in the width direction of the sheet so that the net-like metal thin film does not move. This can be achieved by a flexible joint in which the mesh-like metal thin film does not exist at the portions where both ends of the canvas are riveted to the support of the duct.

[0008] Furthermore, the object is to provide a reticulated metal thin film that intercepts electromagnetic waves between the insulating sheets, so that the reticulated metal thin film does not move in a linear manner at a central portion in the width direction of the sheet. A canvas is formed by sewing, and both side edges of the bonded canvas are sewn and reinforced, and a structure in which the reticulated metal thin film does not exist in a portion to be fixed by rivets on both side edges of the canvas, and a net shape A reinforcing wire is wrapped around the central portion of the metal thin film to form a canvas. The canvas is formed by reinforcing it to maintain the entire annular or square shape, and the canvas is fixed to the portions fixed by rivets on both sides of the canvas. This can be achieved by a reinforced configuration in which no reticulated metal thin film is present or the entire ring or square shape is maintained.

[0009] The flexible joint of the present invention is formed of a sheet of insulating non-combustible fiber, and a micro-expanded metal (net-like punching metal) having a thin honeycomb structure is arranged between the sheets. When mounted between the flanges, it is possible to suppress leakage of the internal electromagnetic waves to the outside. Moreover, since it is a non-metallic stretchable material, it is insulative and can prevent electrical disturbances such as static electricity. Further, the flexible joint of the present invention can be formed in a cylindrical shape or a polygonal shape.

The insulating sheet of the present invention can use a fabric made of noncombustible inorganic fibers such as glass fiber and ceramic. Further, a cloth coated on the surface with a natural or synthetic resin or rubber can be used. The flexible joint of this invention can reliably block electromagnetic waves with a simple structure that is a modification of the conventional flexible joint.

[0011]

[Embodiment of the invention]

 Hereinafter, embodiments of the flexible joint according to the present invention will be described with reference to the drawings. FIG. 1 is a partially cutaway perspective view of an embodiment of a canvas used for the flexure joint of the present invention. FIG. 2 is a plan view and a sectional view of a first embodiment of the canvas of the present invention. FIG. 3 is a plan view showing a second embodiment of the canvas of the present invention. FIG. 4 is a front view showing a state in which the flexible joint of the present invention is mounted between angle support members of the duct. The upper half shows the first embodiment, and the lower half shows the second embodiment. FIG. 5 is a cross-sectional view of a main part showing a state where the flexible joint of the present invention is attached to a duct support. FIG. 6 is a central longitudinal sectional view of a canvas used for the flexible joint of the present invention.

The flexible joint according to the present invention will be described based on an embodiment shown in the drawings. Blanks are provided at both ends of the surface of a sheet 1 made of a non-combustible inorganic fiber such as an insulating glass fiber or a ceramic, and a reticulated metal thin film 2 such as a punching metal is disposed at the center. The sheet 1 is stacked and covered on the surface of the reticulated metal thin film 2, and the sheet 1 is wrapped around the center line 3 in the width direction and sewn to form a canvas. The holding plate 4 is fixed by an angle flange 5 which is a supporting frame. Since the width of the reticulated metal thin film 2 is formed to be slightly longer than the effective dimension of the flexible joint, if the flat metal is developed and replaced with a flat surface, the angle flange 5 and the reticulated metal thin film 2 overlap as shown in FIG. The state is the same as that of being surrounded by metal, and the passage of electromagnetic waves can be blocked.

The metal metal used in the present invention is formed of a thin net-like metal thin film 2 and has very small holes. This hole has a large number of fine through-holes of about 1 μ to 0.2 μ and is called a micro-expander metal. In addition, a canvas is formed by sewing both side edges together with the insulating sheets 1 and 1 stuck together, thereby forming a durable flexible joint.

The shape of the flexible joint configured as described above is generally cylindrical, but may be rectangular. When the sheet 1 is formed into a cylindrical shape, a piano wire or the like is formed so as to surround the cylindrical body between the outer sheet 1 forming the cylindrical body and the internal net-like metal thin film 2 in order to prevent deformation of the shape. (See FIG. 4). The reinforcing wire 7 may be inserted between the net-like metal thin film 2 and the inner sheet 1.

As shown in FIG. 5, a reticulated metal thin film 2 is circulated between the sheets 1 and 1. Both ends 1a, 1a of the sheets 1, 1 are fixed to angle flanges 5 of a pressing plate 4 of the duct by rivets 6. The reticulated metal thin film 2 does not exist in the portion where the rivet 6 penetrates. As described above, both ends of the net-like metal thin film 2 are sandwiched by the angle flanges 5, but since the insulating sheet 1 of the canvas is interposed, the electromagnetic waves contained in the exhaust gas passing through the inside of the flexible joint are cut off, and the joint portion is formed. There was no danger of leaking outside.

In the case of a normal duct flexible joint, leakage of 80 to 90% of electromagnetic waves from exhaust gas passing through the duct was confirmed. However, when the flex joint of the present invention was used, the leakage was reduced to several percent or less. It was confirmed that there was. Measurement Results A reticulated metal thin film having a thickness of 0.05 mm was used, and a polyparaphenylene benzobisoxazole fiber disposed between sheets made of flame-retardant fibers was used. Measuring equipment Trifield Meter (made in the United States) Distance from duct peripheral wall (cm) 10 20 30 Conventional product (Milligauss) 55.0 27.0 7.0 Invention (Milligauss) 7.5 0.7 0.5 As described above Leakage of electromagnetic waves when using this flexure joint was very small. In particular, when it was separated by 30 cm or more, the existence of electromagnetic waves could not be confirmed.

[0017]

[Effect of the invention]

 In the flexible joint according to the present invention, since the wire mesh metal of a lightweight metal thin film that blocks electromagnetic waves is arranged in a canvas formed of a flexible stretchable noncombustible insulating sheet, the electromagnetic waves are reliably blocked. It is possible to suppress the leakage of electromagnetic waves, and in particular, it can be used as a ventilation duct in medical institutions and the like to eliminate adverse effects on medical instruments and the like.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of an embodiment of a canvas used for the flexure joint of the present invention.

FIGS. 2A and 2B are explanatory views of a first embodiment of the canvas of the present invention; FIG. 2A is a plan view; FIG.

FIG. 3 is a plan view showing a second embodiment of the canvas of the present invention.

FIG. 4 is a front view showing a state in which the flexible joint of the present invention is mounted between angle support members of a duct, wherein an upper half shows a first embodiment and a lower half shows a second embodiment.

FIG. 5 is a sectional view of a main part showing a state in which the flexible joint of the present invention is attached to a duct support.

FIG. 6 is a central longitudinal sectional view of a canvas used for the flexible joint of the present invention, in which an upper half shows a first embodiment and a lower half shows a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet 2 Reticulated metal thin film 3 Center line 4 Holding plate 5 Angle flange 6 Rivet 7 Reinforcing line

Claims (4)

[Utility model registration claims] 1. A flexible joint used for a seam arranged to connect two exhaust and ventilation ducts installed in a room or the like, wherein a peripheral wall formed around the flexible joint is formed of two insulating sheets. A flexible joint comprising a canvas having a predetermined width of a mesh-like metal thin film for shielding electromagnetic waves between the sheets. 2. A reticulated metal thin film for intercepting an electromagnetic wave is interposed between said insulating sheets, and is linearly sewn at a central portion in a width direction of said sheet so that said reticulated metal thin film does not move. The flexible joint according to claim 1, wherein a canvas is formed, and the reticulated metal thin film does not exist in a portion where both side edges of the canvas are riveted to a support for the duct. 3. A reticulated metal thin film for intercepting an electromagnetic wave is interposed between said insulating sheets, and is linearly sewn at a central portion in the width direction of said sheet so that said reticulated metal thin film does not move. A flexible joint comprising a canvas formed and sewn on both side edges of the bonded canvas, and a rivet on both side ends of the canvas to which the mesh-like metal thin film does not exist. 4. A reticulated metal thin film for intercepting electromagnetic waves is interposed between said insulating sheets, and is sewn linearly at a central portion in the width direction of the sheet so that the reticulated metal thin film does not move. A reinforcing wire is laid at the center of the net-like metal thin film, and reinforcement is performed to maintain the whole annular or angular shape to form a canvas. A flexible joint characterized by the absence of a thin film.