JP2000197231A - Slot-removing tool for optical cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slot-removing tool for optical cable, which can completely cut off a slot without giving significant damages to a tension member by optimizing the position of its blade. SOLUTION: A slot-removing tool for optical fiber, which removes a slot 3 covering a tension member 2 of an optical fiber, is constituted in such a way that a blade 15 which cuts off the slot 3, when an insertion block, into which the slot 3 and member 2 are inserted is rotated, is attached to the insertion block. An angle α of the blade 15 from the perpendicular surface of the inserted member 3, a distance X between a tangent 27 to the member 2 and cutting edge 26 of the blade 15, and a distance Y between a diametral line 28 of the member 2 perpendicular to the tangent 27 and the cutting edge 26 are respectively adjusted to 1-5 deg., 0-2 mm, and -1 mm to +2 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool for exposing a tension member by cutting and removing a slot of an optical cable.

[0002]

2. Description of the Related Art As shown in FIG.
A tension member 2 disposed at the center, a slot 3 (spacer) covered by the tension member 2, a plurality of optical fiber cores 4 disposed on the outer periphery of the slot 3, and a cable winding covering the optical fiber core 4 A cable sheath 6 covered with the cable upper winding part 5. Such an optical cable 1 is used when a part of the optical fiber 4 is branched or a part or a front part is connected.
It is necessary to remove the sheath 6 and the upper winding portion 5 and further remove the slot 3 to expose the tension member 2.

Conventionally, the removal of the slot 3 has been manually performed using a nipper, knife, pliers, or the like, thereby exposing the tension member 2 having a required length. However, the cutting and removing operation of the slot 3 by a manual operation using a normal tool is performed as follows.
It is easily affected by the skill of the worker, and it is difficult to remove the slot 3 stably in a short time. In other words, the operator frequently uses different tools so as not to damage the optical fiber core wire 4 and moves the body over a wide area to cut the entire circumference of the slot 3 while taking care not to injure the fingertips and the like. Need to have a large workload.

Therefore, in recent years, the slot 3 and the tension member 2 are inserted into an insertion block on which a cutting blade is attached, and the insertion block is rotated to cut and remove the slot 3 in a pencil-sharpening manner by the cutting blade, thereby removing the tension member 2. An optical cable slot removing tool that is exposed has been developed.

[0005]

However, according to the study of the present inventors, the arrangement of the cutting blade with respect to the tension member 2 is always optimum in the conventional pencil sharpening type slot removing tools. However, it is concluded that there is a possibility that the slot 3 is not completely peeled off and remains on the surface of the tension member 2, or the tension member 2 is damaged by the cutting blade, leaving room for improvement. Reached.

SUMMARY OF THE INVENTION An object of the present invention, which has been made in view of the above circumstances, is to optimize a position of a cutting blade, and to provide a slot removing tool for an optical cable capable of completely removing a slot without significantly damaging a tension member. To provide.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an optical cable having an insertion block in which the slot and the tension member are inserted, in order to remove the slot covered by the tension member. A slot removing tool for an optical cable having a cutting blade for cutting and removing a slot by rotation, wherein an angle α of the cutting blade with respect to an orthogonal plane of an inserted tension member is 1
The distance X from the tangent of the tension member to the cutting edge of the cutting blade is 0 to 2 mm, and the distance Y from the diameter line of the tension member perpendicular to the tangent to the cutting edge.
Is set to -1 to +2 mm.

The cutting blade comprises a cutting blade formed along the radial direction of the slot and a scooping blade formed along the axial direction of the slot. May be the cutting edge.

The insertion block having the cutting blade may be integrally provided at one end or both ends of the tool holding block.

The insertion block having the cutting blade may be detachably attached to one or both ends of the tool holding block.

A plurality of types of slot guides having an inner diameter corresponding to the outer diameter of the slot may be removably attached to the insertion block having the cutting blade.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment is shown in FIGS.

As shown in FIG. 3, the slot removing tool 7 of the optical cable 1 according to the present embodiment is applied to the optical cable 1 having a capacity of several to several thousand cores, and includes a tool holding block 8 formed in a cylindrical shape. , And insertion blocks 9 provided at both ends of the tool holding block 8. Since the insertion block 9 has substantially the same shape on the left and right, only one (right side in FIG. 3) will be mainly described.

The insertion block 9 has an outer diameter formed in a substantially columnar shape, into which the slot 3 and the tension member 2 (before the slot is removed) shown in FIG. 11 are inserted.
Specifically, as shown in FIGS. 4 (a), (b) and (c), the insertion block 9 has a slot inlet 10 formed slightly larger than the outer diameter of the slot 3, and a tension member. The tension member introduction port 11 is formed to have a diameter slightly larger than the outer diameter of the tension member 2.

Since the slot 3 and the tension member 2 are coaxial, the slot introduction port 10 and the tension member introduction port 11 are formed coaxial with each other.
The slot 3 is inserted into the slot introduction port 10 so as to be freely inserted and removed and rotatably about an axis, and the tension member introduction port 11 is provided with the tension member 2 which has been cut and removed to expose the tension member 2 as described later. Inserted. The step 12 formed between the slot introduction port 10 and the tension member introduction port 11 functions as a stopper for pressing the cut surface of the slot 3.

The insertion block 9 has a slot introduction port 10 and a tension member introduction port 11 as shown in FIG.
And the portion is connected to 1 /
A slot chip discharge port 13 cut into a two-disk shape is formed. The slot chip discharge port 13 includes a bottom surface 14 on which the slot introduction port 10 and the tension member introduction port 11 are formed, and a cutting blade 15 for cutting and removing the slot 3.
Is formed from the cutting blade mounting surface 16 to which the tool is mounted, and the end surface 17 of the tool gripping block 8 opposed thereto.

As shown in FIG. 4B, the angle α of the center line 18 of the slot introduction port 10 with respect to the orthogonal plane 19 of the cutting blade mounting surface 16 is set to 1 to 5 degrees. Thereby, the cutting blade 15 attached to the cutting blade attachment surface 16,
The angle α between the slot 3 (tension member 2) inserted into the slot inlet 10 and the orthogonal plane 19 is set to 1 to 5 degrees.

As shown in FIGS. 1 and 2, the cutting blade 15 has a flat plate portion 21 having a mounting hole 20 formed therein and a slot 3.
And a scooping blade 23 formed along the axial direction of the slot 3 are formed integrally with each other. Cutting blade 22 and scooping blade 23
Is formed on one side surface of the cutting blade 15, and the other side surface 24 of the cutting blade 15 is flat. The cutting blade 15 is attached to the insertion block 9 by a screw 25 or the like inserted into the mounting hole 20 so that the other side surface 24 is in close contact with the cutting blade mounting surface 16. α is set to 1 to 5 degrees.

The cutting edge portion 22 formed along the radial direction of the slot 3 has a function of cutting the front end face of the slot 3 with the relative rotation of the slot 3 and is formed in the slot 3 along the axial direction. The scooped blade portion 23 has a function of peeling the cut slot from the tension member 2. The cutting blade 22 and the scooping blade 23 are connected at a right angle,
These connection points are defined as the cutting edge 26 of the cutting blade 15.

FIG. 1 shows the positional relationship between the cutting edge 26 of the cutting blade 15 and the tension member 2. As shown, the distance X from the tangent 27 of the tension member 2 to the cutting edge 26 is 0.
２2 mm, the distance Y from the diameter line 28 of the tension member 2 orthogonal to the tangent line 27 to the cutting edge 23
Is set to -1 to +2 mm. Also, the cutting blade 2
The length of 2 is set to a length that partially protrudes from the surface of the slot 3.

On the other hand, inside the tool gripping block 8, a tension member insertion hole 29 into which the tension member 2 whose slot 3 is cut off by the cutting blade 15 and which is exposed is inserted, is provided in the tension member introduction port 11. It is formed so as to be connected. Tool holding block 8
A window 30 communicating between the inside and outside of the tension member insertion hole 11 is formed on the side surface of the first member. In the vicinity of the window 30,
Scale 31 with the length written from step 12
Is provided.

The operation of this embodiment having the above configuration will be described.

As shown in FIG. 11, when the slot 3 (made of plastic such as polyethylene) of the optical cable 1 is cut off to expose the tension member 2 (made of plastic containing copper wire or glass fiber), first, the cable is exposed. The sheath 6 and the upper cable winding 5 are removed, and the optical fiber core 4 is moved to expose the slot 3.

Then, the slot 3 (containing the tension member 2) is inserted into the slot inlet 10 of the insertion block 9 of the slot removing tool 7 as shown in FIG. The tool gripping block 8 is rotated around the axis while pressing against the step 12 shown in FIG.
5 is inserted into the slot 3). The rotation of the tool holding block 8 may be performed manually by an operator, or may be performed mechanically by chucking the tool 7 to some rotating device (an electric drill or the like).

Then, the leading end surface of the slot 3 is cut by the cutting blade 22 of the cutting blade 15, and the cut slot is peeled off from the tension member 2 by the scooping blade 23 of the cutting blade 15, as shown in FIG. Slotted chips 3
2 is discharged from the slot chip discharge port 13. Then, the exposed tension member 2 is inserted into the tension member insertion hole 29 in the tool gripping block 8, and the scale 31 provided near the window 30 is read to read the length of the tension member 2 (stepped portion). 12).

Here, when the slot 3 is cut by the cutting blade 15, in the slot removing tool 7 according to the present embodiment, the distance X is set to 0 to 2 mm and the distance Y is set to -1 in FIG. Since the angle α is set to 1 to 5 degrees in FIG. 4B, the slot 3 is not significantly damaged.
Can be completely cut off, and the slot cutting chips 32 are discharged in a connected state as shown in FIG. 3 without being fragmented.

The reason for setting the distance X to 0 to 2 mm is that the slot cut by the cutting blade 22 is
This is because, when peeling off from the tension member 2 and the uncut portion slot, the cut slot 3 is peeled off from the outer periphery of the tension member 2 and the uncut portion slot without breaking. The distance X is set smaller as the diameter D of the tension member 2 is smaller.

When the distance X is larger than 2 mm, the slot 3 cut by the cutting blade 22 is cut off without being peeled off from the tension member 2 and the uncut portion slot, or is cut by the scooping blade 23. Part of the slot 3 remains on the surface of the tension member 2 and is difficult to remove. On the other hand, if the distance X is smaller than 0 mm, the blade edge 26 becomes less than the tension member 2 in consideration of the dimensional difference (play) between the outer diameter of the slot 3 and the inner diameter of the slot inlet 10.
And the tension member 2 may be damaged.

Similarly, the reason why the distance Y is set to -1 to +2 mm is that when the slot 3 cut by the cutting blade portion 22 is peeled off from the tension member 2 and the uncut portion slot by the scooping blade portion 23, the cutting is performed. This is for stripping the cut slot 3 from the outer periphery of the tension member 2 and the uncut portion slot without breaking. The distance Y is determined by the adhesion force between the slot 3 and the tension member 2 and the strength of the cut slot and the unexcavated portion. If the adhesion force is strong, the distance Y is shifted in the minus direction up to -1 mm. Is weak, it is shifted in the plus direction up to +2 mm.

When the distance Y is smaller than -1 mm, the slot 3 cut by the cutting blade 22
As a result, a part of the slot 3 remains on the surface of the tension member 2 and is difficult to remove. On the other hand, if the distance Y is +
Even if it is larger than 2 mm, the slot 3 cut by the cutting blade 22 is similarly cut or cut by the scooping blade 23, and a part of the slot 3 remains on the surface of the tension member 2 and is difficult to remove. Becomes

The angle α indicates the angle at which the cutting blade 15 cuts into the tip end surface of the slot 3, and the cutting amount (slot) of the slot 3 by the cutting blade 22 when the slot removing tool 7 (cutting blade 15) makes one rotation. (Thickness of the cutting chips 32). As the angle α increases, the thickness of the slot 3 to be cut increases, but a large rotational force (torque) is required. Therefore, the angle α is limited to 5 degrees for a hand tool.

On the other hand, when the angle α is smaller, the thickness of the slot 3 cut by the cutting blade 22 becomes thinner. Therefore, when the thin slot 3 is peeled off from the tension member 2 and the unexcavated portion slot by the scooping blade 23. In addition, the cut slot 3 is broken due to insufficient strength, and a part of the slot 3 remains on the surface of the tension member 2 and is difficult to remove.

According to the slot removing tool 7 according to the present embodiment, the distance X = 0 to 2 mm, the distance Y = −1 to +2 mm,
Since the angle α is set to 1 to 5 degrees, the slot 3 cut by the cutting blade portion 22 is peeled off from the upsetting tension member 2 without breaking, and the tension member 2
The slot 3 can be completely and efficiently removed in a short time without causing significant damage to the slot.

The removal of the slot 3 from the tension member 2 can be achieved by simply rotating the tool 7 while pushing the slot 3 into the slot introduction port 10 of the slot removing tool 7. No skills are required. The tension member 2 of the cutting edge 26 of the cutting blade 15
, The work result has little variation. Further, since the cutting blade 15 is not exposed, the operator is not injured by the cutting blade 15.

Further, since the operator only needs to rotate the slot removing tool 7, the operator can work in a narrow space.
Further, since the slot removing tool 7 is rotated without moving the optical cable 1 (slot 3) side, there is no adverse effect such as impact on the optical fiber core wire 4 while the slot 3 is being cut off. The work (hot wire work) can be performed also on the optical cable 1 (hot wire) transmitting the optical signal by the wire 4.

In addition, in the slot removing tool 7 according to the present embodiment, since the insertion blocks 9 are provided at both ends of the tool gripping block 8, as shown in FIG. If the dimensions are different,
Different types of optical cables 1 having different diameters of the slots 3 can be accommodated. The dimensions of the tension member inlet 11 may be made different so that the tension members 2 correspond to the optical cables 1 having different diameters. According to the present embodiment, when the types of the optical cables 1 are two or less,
This can be handled by the insertion blocks 9 on the left and right sides.

A second embodiment is shown in FIGS.

As shown, this embodiment has the same basic configuration as the previous embodiment shown in FIGS. 1 to 5, and the same components are denoted by the same reference numerals. The description will be omitted, and only the differences will be described.

The difference between the slot removing tool 7a of the present embodiment and the slot removing tool 7 of the previous embodiment is that the insertion block 9 is provided integrally at both ends of the tool holding block 8 in the previous embodiment. This embodiment is characterized in that the insertion block 9 is detachably attached to one end of the tool holding block 8.

That is, the insertion block 9 is formed with a substantially hexagonal columnar projection 33, and the tool gripping block 8 is formed with the projection 3
A substantially hexagonal hole-shaped concave portion 34 into which the 3 is disengaged is formed. A locking groove 35 is formed in the convex portion 33, and a locking screw 36 whose tip contacts the locking groove 35 is provided in the tool gripping block 8.

According to the present embodiment, if the insertion blocks 9 are prepared in advance in accordance with various types of optical cables 1 having different diameters of the slots 3 and the tension members 2, respectively, the tool gripping blocks can be obtained at the work site. By appropriately attaching and detaching various insertion blocks 9 to and from the optical cable 8, various types of optical cables 1 can be instantaneously handled. This embodiment is suitable when the diameter of the slot 3 and the diameter of the tension member 2 are frequently changed. In addition, it is needless to say that the same operation and effect as the previous embodiment can be exhibited.

FIGS. 9 and 10 show a third embodiment.

As shown, the basic configuration of this embodiment is the same as that of the second embodiment shown in FIGS. 6 to 8, and the same reference numerals are given to the same components. The description will be omitted, and only the differences will be described.

The slot removing tool 7b of the present embodiment is similar to the slot removing tool 7a of the second embodiment.
The second point is that a plurality of types of slot guides 36 having an inner diameter corresponding to the outer diameter of the slot 3 are detachably attached.
This is different from the slot removing tool 7a of the embodiment.

That is, the insertion block 37 is provided with the engagement hole 37.
Are formed, and the slot introduction port 38 is provided in the engagement hole 37.
Is detachably attached. The slot guide 36 includes a cylindrical portion 39 inserted into the engagement hole 37 and a flange portion 40 that is in close contact with the end surface of the insertion block 9 during insertion. A locking groove 41 is formed in the cylindrical portion 39, and a locking screw 42, the tip of which abuts on the locking groove 41, is provided in the insertion block 9.

According to the present embodiment, if slot guides 36 having different slot introduction ports 38 are prepared in advance for various types of optical cables 1 having different diameters of the slots 3 at the work site, By appropriately attaching and detaching the guide 36 to and from the insertion block 9, various types of optical cables 1 having the same diameter of the tension member 2 but different in the diameter of the slot 3 can be instantaneously accommodated.
Moreover, it is more economical than replacing the entire insertion block 9. In addition, it is needless to say that the same operation and effect as the previous embodiment can be exhibited.

Next, examples of typical experimental results performed by the present inventors will be described.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

As described above, according to the slot removing tool for an optical cable according to the present invention, the following excellent effects can be exhibited.

(1) Since the arrangement of the cutting blades is optimally set, the slots can be completely and efficiently cut in a short time without significantly damaging the tension members.

(2) Since only the tool needs to be rotated, a high level of skill and skill is not required for the operator.

(3) Since only the tool is rotated, the working space is reduced.

(4) Since there is no influence on the optical fiber core, the hot wire operation can be performed.

(5) By replacing the insertion block and the slot guide, various optical fibers can be economically handled.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a main part of a slot removing tool for an optical cable according to an embodiment of the present invention.

FIG. 2 is a three-view drawing showing a cutting blade of the slot removing tool, (a) is a front view, (b) is a plan view, and (c) is a side view.

FIG. 3 is a plan view of the slot removing tool.

FIGS. 4A and 4B are explanatory views showing a main part of the slot removing tool, wherein FIG. 4A is a side view, FIG. 4B is a plan view, and FIG.

FIG. 5 is a sectional view taken along line VV of FIG. 4 (c).

FIG. 6 is a plan view of a slot removing tool showing another embodiment.

7A and 7B are explanatory views showing an insertion block of the slot removing tool, wherein FIG. 7A is a side sectional view and FIG. 7B is a plan view.

FIG. 8 is a sectional view taken along line VIII-VIII in FIG. 7 (a).

FIG. 9 is a plan view of a slot removing tool showing still another embodiment.

10A and 10B are explanatory diagrams showing an insertion block of the slot removing tool, wherein FIG. 10A is a side sectional view and FIG. 10B is a plan view.

FIG. 11 is an explanatory diagram showing an outline of an optical cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical cable 2 Tension member 3 Slot 9 Insertion block 15 Cutting blade 19 Orthogonal surface 22 Cutting blade 23 Scooping blade 26 Cutting edge 27 Tangent line 28 Diameter line 36 Slot guide α Angle X distance Y distance

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Suzuki 5-1-1, Hidaka-cho, Hitachi City, Ibaraki Prefecture F-Term in Power Systems Research Laboratory, Hitachi Cable, Ltd. 5G353 AA02 AC02 CA04 CA07 DA06 EA01 EA02

Claims (5)

[Claims] 1. An optical cable, comprising: an insertion block into which the slot and the tension member are inserted; and a cutting blade for cutting and removing the slot by rotation of the insertion block in order to remove a slot covered by a tension member of the optical cable. A slot removing tool, wherein the angle α of the cutting blade with respect to the orthogonal plane of the inserted tension member is 1 to 5 degrees, the distance X from the tangent of the tension member to the cutting edge of the cutting blade is 0 to 2 mm, A distance Y from the diameter line of the tension member, which is orthogonal to the above, to the cutting edge is -1 to +2 mm. 2. The cutting blade comprises a cutting blade formed along the radial direction of the slot, and a scooping blade formed along the axial direction of the slot. 2. The optical cable slot removing tool according to claim 1, wherein the point of connection with the slot is the cutting edge. 3. The optical cable slot removing tool according to claim 1, wherein the insertion block having the cutting blade is provided integrally at one or both ends of the tool holding block. 4. The optical cable slot removing tool according to claim 1, wherein the insertion block having the cutting blade is detachably attached to one or both ends of the tool holding block. 5. The slot removing tool for an optical cable according to claim 1, wherein a plurality of types of slot guides having an inner diameter corresponding to an outer diameter of the slot are detachably attached to the insertion block having the cutting blade.