JPH0421841B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method and tool for cutting optical fibers so that the cut surface is smooth and perpendicular to the axis of the fiber.

In order for optical energy signals to pass efficiently through a spliced portion of an optical fiber, the end face of the fiber at the spliced portion must be smooth and perpendicular to the axis of the fiber. A scribing and breaking method is known as a method for cutting optical fibers so as to obtain such end faces. In this method, an optical fiber is stretched on an arcuate surface, and then lightly pulled with a sharp blade to create a split, and the split is transmitted in the diametrical direction.

The hand tools conventionally used to score and break optical fibers have many moving parts, are complex in structure, and are expensive. For example, US Patent Nos. 4154385, 4159793, 4168026
No. 4202475. Also,
Since such tools are often used outdoors under harsh conditions and are required to withstand repeated use, they need to be structurally durable and easy to repair. Furthermore, since tools are often lost when working outdoors, it is desirable that the structure be simple and inexpensive.

In view of these circumstances, it is an object of the present invention to provide a tool for cutting optical fibers by a scribing and breaking method so that the cut surface is smooth and perpendicular to the axial direction.

A further object of the present invention is to provide a tool as described above which has few moving parts and has a relatively simple structure.

A further object of the present invention is to provide a tool as described above that can be manufactured easily and inexpensively.

The tool of the present invention includes an optical fiber support surface having an arcuate convex surface. A scribing blade is supported at a distance from the supporting surface and extends laterally to the supporting surface, and when the scribing blade is moved perpendicularly to the supporting surface, the scribing blade is The surface that the blade passes through is defined as the scribing surface. Spring members for holding down and applying tension to the optical fiber are disposed on both sides of the scribed surface between the optical fiber support surface and a support surface opposite the support surface.
When the support surfaces are moved toward each other, the spring members are compressed and the optical fiber is held between the grip portion of each spring member and the optical fiber support surface. Further compression of the spring member causes the grip portions to move in opposite directions along the optical fiber support surface and away from the scribing surface. This places an axial tensile stress on the optical fiber. When the optical fiber is subjected to bending stress and axial tensile stress in this way and is lightly scored with the scribing blade, the split is transmitted in the diametrical direction and the optical fiber breaks.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIGS. 1 and 2, a hand tool 10 for cutting optical fibers according to an embodiment of the present invention includes an anvil 12 that is a support member for optical fibers, a spring member 14, and a scribing blade 18 (a scribing member in the center) that constitutes a scribing member. It consists of a support surface member 16 and a truncated pyramid-shaped frame 20, which constitute a plate-like member that supports the structure shown in FIG. 3). The anvil 12 includes an optical fiber support surface 22 forming an arcuate convex support surface extending between both ends 24, and a second surface 26 on the opposite side of the optical fiber support surface 22.

The spring member 14 is an elongated plate formed to surround the anvil 12, and has U-shaped free ends 28 located on both sides of the scribing surface determined by the scribing blade 18. ing. Spring member 14 extends symmetrically on either side of the scribing surface and extends adjacent to two grip portions 30, opposite ends 32 bent around opposite ends 24 of said anvil 12, and said second surface 26 of said anvil 12. It consists of an elongated bottom portion 34. Each end 32 thereof is provided with an optical fiber insertion slot 36, and the bottom 34 is provided with a deformable concave portion 38.

The optical fiber support surface 22 and the spring member 1
The supporting surface members 16, which are opposite each other with the U-shaped free ends 28 of the four U-shaped free ends 28 in between, are provided with adjustable attachment means 40 (e.g., consisting of a pair of nuts, bolts and elastic washers).

The anvil 1 is disposed within the truncated pyramidal frame 20.
2. The spring member 14 and the support surface member 16 are housed. The frame 20 has the mounting means 4
a top wall 42 with a pair of holes 44 for receiving 0;
It includes a bottom wall 46 having an opening 48 large enough to accommodate a finger, a rear wall 50, and a front wall 52 having a slot 54 extending therethrough.
Frame 20 has opposite end walls 56 each having an optical fiber insertion slot 58.

When cutting an optical fiber using the hand tool 10 of this embodiment, the optical fiber 60 is inserted through the slot 54 of the front wall 52 of the frame 20 and into the optical fiber insertion slot 36 of the spring member 14 and the end thereof, as shown in FIG. Thread the optical fiber through the optical fiber insertion slot 58 in the wall 56. The optical fiber 60 is inserted into one of the optical fiber insertion slot 36 of the spring member 14 and the optical fiber insertion slot 58 of the end wall 56 of the frame 20, and the optical fiber 60 is inserted into the optical fiber support surface 2.
It may be designed for lateral positioning on 2. Spring member 14 is not moved during insertion of optical fiber 60.

Next, as shown in FIG. 4, force is applied by placing a finger on the deformable concave portion 38. This causes the U-shaped free end 28 of the spring member 14 to be compressed between the support surface member 16 and the optical fiber support surface 22 of the anvil 12, so that the anvil 12 is supported by the support surface member 16. Move towards.
The grip portion 30 presses the optical fiber 60 against the optical fiber support surface 22 when its free end 28 is compressed. Furthermore, during compression, the grip portion 3
0 slide longitudinally along the optical fiber support surface 22, the free ends 28 of the U-shape move away from the scribing surface in opposite directions. This causes tensile stress in the axial direction to act on the optical fiber 60.

In this way, the optical fiber 60 is finally brought into contact with the scribing blade 18 as shown in FIG.
At this point, the optical fiber 60 is subject to bending stress and axial tensile stress, which eventually reduces the tensile stress across the cross section of the fiber.
Here, when the optical fiber 60 is lightly scratched with the scribing blade 18, the formed split is gradually transmitted.
The scribing blade 18 can be rotated slightly around the scribing surface by using the adjustable attachment means 40. Such adjustment is especially important when the scribing blade 18 becomes worn after use, in order to keep the cut surface clean. Furthermore, when the support surface member 16 is worn out to the point where it cannot be used, the support surface member 16 is removed from the frame 2.
The scribing blade 18 can be easily replaced by removing it from the top wall 42 of 0 and replacing it.

As is clear from the above description, the optical fiber cutting tool of the present invention includes a substantially rectangular frame, a scribing blade, an integral spring member, and an anvil having a convex surface. Therefore, since the number of components is extremely small and the structure is simple, it is easy to downsize and a hand tool that can be easily operated with the fingers of one hand can be obtained. Further, by simply pressing with a finger, an appropriate tension is applied to the optical fiber by the convex surface of the anvil and the spring member, and the optical fiber can be cut with a smooth fracture surface.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view of a hand tool for cutting optical fibers according to an embodiment of the present invention, Fig. 2 is a perspective view of the assembled state of the hand tool, and Figs. FIG. 3 is a cross-sectional view showing a procedure for cutting an optical fiber. 12...anvil, 14...spring member,
16...Supporting surface member, 18...Scoring blade, 20...
...Frame, 22... Optical fiber support surface.

Claims (1)

[Scope of Claims] 1. A generally rectangular frame having a top wall, a bottom wall, and both end walls, a scribing blade attached approximately to the center of the top wall of the frame, and a scribing blade approximately near the end wall of the frame. It is bent into a U-shape, and the free ends are spaced apart from each other so that the shape is approximately U-shaped.
a one-piece spring member bent into a shape and resiliently housed within the frame such that the scribing blade is disposed between the spaced apart free ends; a support member having a convex surface, and an optical fiber insertion slot is provided on both end walls of the frame and on both sides of the spring member to place the optical fiber between the convex surface of the support member and the spring member; The spring member and the support member are moved toward the top wall of the frame through the opening in the bottom wall of the frame to press the optical fiber between the spring member and the convex surface of the support member to remove the optical fiber. An optical fiber cutting tool characterized in that the scribing blade cuts the fiber while applying bending stress and axial tensile stress to the fiber.