JPH034103Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a branch wiring device for undercarpet cables used for interconnecting telephones or microcomputer application equipment in offices and the like.

[Prior art and its problems]

In recent years, as the performance of microcomputers has improved and their prices have fallen, microcomputer-applied equipment has become widespread in offices, laboratories, factories, and other offices.

Traditionally, this type of application equipment was designed with the assumption that each device would be used independently, and its capabilities were limited by the amount of data it held.However, so-called local network systems That is, by adopting a system in which a common data bank and each device are connected to each other, effective use of data held by each device is attempted.

As a cable used to connect the microcomputer application equipment, there is a so-called under-carpet cable (hereinafter referred to as a cable) which is laid under the carpet.

Figures 1 and 2 show a conventional example of the above-mentioned cable, in which a pair of core wires 2 made of optical fibers or conductor wires are buried in the center of a belt-shaped outer sheath 1. In addition, a pair of reinforcing wires 3A and 3B made of piano wire or the like are embedded on both sides of the core wire 2.

In the above-mentioned cable, the core wire 2 is protected by supporting the reinforcing wires 3A and 3B against the compressive load that is received when the cable is laid under a carpet and is stepped on by a person.

By the way, when the above-mentioned cable is wired in a bent state as shown in FIG. 2, the difference between the bending radius R ₁ of the inner reinforcing wire 3A and the bending radius R ₂ of the outer reinforcing wire 3B causes the bending of both reinforcing wires 3A and 3B. External sheath 1
A difference arises in the amount of protrusion ₁ and ₂ from the end of the cable, which becomes an obstacle when attaching a branch wiring fitting for the core wire 2 to the end of the cable, for example.

Furthermore, in order to obtain sufficient mechanical strength, piano wire, for example, is used for the reinforcing wires 3A and 3B, and many difficulties arise in trimming the ends of such materials.

[Purpose of invention]

The present invention was developed in view of the above circumstances, and an object of the present invention is to prevent the reinforcing wires from protruding from the terminal of the outer sheath when an undercarpet cable including a plurality of reinforcing wires is wired in a bent state.

[Structure and action of the device]

In order to achieve the above object, the present invention provides a casing attached to the end of an undercarpet cable with a swing arm rotatable about an axis, and connects reinforcing wires to both ends of the swing arm. , the expansion and contraction force of one reinforcing wire is applied to the other reinforcing wire.

[Example of idea]

3 to 6 show an embodiment of the present invention, and this branch wiring fitting includes a casing 4 made of plastic or the like and a cover 6 fixed to the casing 4 with bolts 5. This is the basic configuration.

The casing 4 is formed with a lead-in port 7 for pulling in the outer sheath 1 of the cable, and a lead-in port 8 for drawing out the core wire 2 branched from the outer sheath 1. Further, a support shaft 9 is provided upright on the casing 4, and this support shaft 9 rotatably supports the swing arm 10.

The swing arm 10 is rotatably supported by the support shaft 9 at its center, and has reinforcing wires 3A and 3B at both ends, which are bent as shown by chain lines in FIG. A connecting hole 11 is provided for insertion and engagement.

In addition, the reference numeral 12 in the figure is a protective tube that covers the core wire 2 protruding from the outer sheath 1, and this protective tube 12 has the core wire 2 buried in a fibrous cushioning material 13 filled inside the protective tube 12. While maintaining this state, the external force applied to the core wire 2 is relaxed.

The undercarpet cable to which the branch wiring fittings configured as described above is attached has the reinforcing wire 3
Since the terminal portions of reinforcing wires 3A and 3B are connected via a swinging arm 10 that can freely turn, some relative movement in the longitudinal direction of reinforcing wires 3A and 3B is allowed when the cable is bent. and can be easily bent. Furthermore, when the swing arm 10 is bent beyond its swingable range, the support shaft 9 forcibly restrains the reinforcing wires 3A, 3B to prevent their terminal portions from becoming misaligned. The cable to which the branch wiring device of the present invention is applied has a structure in which reinforcing wires and core wires are embedded in a belt-shaped external sheath 1, as shown in the figure, so it can be bent along the floor surface. In this case, since the outer periphery of the outer sheath 1 will expand and the inner periphery will contract, it is essentially difficult to bend the outer sheath 1 with an extremely small radius of curvature or at an extremely large angle. Also,
When an optical fiber is used as the core wire, a minimum radius of curvature must be ensured in order not to impair the transmission characteristics of the optical fiber. Due to these factors, the branch wiring device of the present invention is exclusively applied to undercarpet cables that have a relatively large radius of curvature and are bent over a very small angle. The difference in circumference between the inner and outer circumferences that occurs in the core wire is relatively small, and therefore, in most cases, the difference in circumference that occurs in the core wire or reinforcing wire can be absorbed by the rotation of the swing arm 10. Furthermore, if a circumferential difference occurs that exceeds the length that can be absorbed by the rotation of the swing arm 10, tensile stress or compressive stress corresponding to this circumferential difference will occur, but as described above, the present invention Since the undercarpet cable to which it is applied is laid with a relatively large radius of curvature, the stress generated per unit length is extremely small. Therefore, if a difference in circumference occurs that exceeds the length that can be absorbed by the swivel arm 10, the entire bent portion of the undercarpet cable will absorb the strain little by little, causing large stress in some parts. Or, or
It is unlikely that the core wire will be damaged or the undercarpet cable will bulge due to the occurrence of large local distortions (which appear as a waving phenomenon in the undercarpet cable).

[Effect of idea]

As explained above, according to the present invention, since a pair of reinforcing wires are connected to both ends of a freely rotatable swing arm, the stretching force generated in opposite directions to both reinforcing wires is applied via the swing arm. This has the effect of allowing slight movement of the reinforcing wire in the longitudinal direction when the undercarpet cable is bent, allowing wiring to be carried out without impairing its flexibility.

[Brief explanation of drawings]

Figures 1 and 2 show a conventional example of an undercarpet cable. Figure 1 is a cross-sectional view, Figure 2 is a plan view, and Figures 3 to 6 are examples of an embodiment of the present invention. 3 is a plan view, FIG. 4 is a view taken along the - line in FIG. 3, FIG. 5 is a view taken along the - line in FIG. 3, and FIG. 6 is a view taken along the - line in FIG. It is an arrow view along the - line of a figure. DESCRIPTION OF SYMBOLS 1... External sheath, 2... Core wire, 3A... Reinforcement wire, 3B... Reinforcement wire, 4... Casing, 6
...cover, 7...drawer port, 8...drawer port,
9...Support shaft, 10...Swivel arm, 11...Connection hole.

Claims (1)

[Scope of utility model registration request] Branch wiring that branches the core wires from the outer sheath by being attached to an undercarpet cable in which a core wire for signal transmission and a pair of reinforcing wires to protect the core wires are buried parallel to each other in a belt-shaped outer sheath. In the device, a casing 4 having an inlet 7 for the outer sheath 1 and an outlet 8 for the core wire 2.
A support shaft 9 is provided in the support shaft, and a connecting hole 11 is connected to the pair of reinforcing wires 3A and 3B, respectively.
A branch wiring tool for an undercarpet cable, characterized in that the central part of a swing arm 10 having a swivel arm 10 at both ends is rotatably supported.