Coating removal blade, removal blade unit and optical fiber coating removal apparatus

A coating removal blade used in an optical fiber coating removal apparatus that removes a coating material of an optical fiber includes a blade tip that is pressed against the coating material from a radial direction of an optical fiber bare wire of the optical fiber, and a pressing surface against which the coating material to be pulled out from the optical fiber is pressed in a longitudinal direction of the optical fiber. The pressing surface includes an inclined surface that is inclined at a constant angle to extend in a direction opposite to a pulling-out direction of the optical fiber as a distance from the blade tip in the radial direction of the optical fiber bare wire increases, and an inclination angle of the inclined surface with respect to the pulling-out direction of the optical fiber is larger than 0° and equal to or smaller than 60°.

TECHNICAL FIELD

The present invention relates to a coating removal blade, a removal blade unit and an optical fiber coating removal apparatus.

This application is a national stage application of PCT Application No. PCT/JP2017/008732, filed on Mar. 6, 2017, which claims priority to Japanese Patent Application No. 2017-028573, filed on Feb. 20, 2017. The contents of the priority applications are incorporated by reference in their entirety.

BACKGROUND

An optical fiber coating removal apparatus has been known which removes a coating material of a terminal portion of each optical fiber in order to connect the optical fibers (coated optical fibers) each having an optical fiber bare wire and the coating material coating the optical fiber bare wire (for example, refer to Patent Document 1).

In the optical fiber coating removal apparatus, the coating material at the terminal portion of the optical fiber is removed by a pair of coating removal blades provided in the optical fiber coating removal apparatus as follows. First, the optical fiber is sandwiched between a pair of upper and lower coating removal blades from a radial direction of the optical fiber bare wire within a range where the pair of coating removal blades bites into the coating material but does not reach the optical fiber bare wire. Thereafter, a portion of the optical fiber extending from the pair of coating removal blades to one side in a longitudinal direction of the optical fiber is moved in a direction of pulling apart (pulling-out direction) with respect to a portion of the optical fiber extending from the pair of coating removal blades to another side in the longitudinal direction of the optical fiber (terminal portion) and then, a portion of the coating material into which the coating removal blades bite is tore off. As a result, the coating material can be pulled out from the terminal portion of the optical fiber and removed.

Patent Document 1 discloses an optical fiber coating removal apparatus in which a pair of guides for supporting an optical fiber so as to sandwich the optical fiber from a radial direction of an optical fiber bare wire is disposed adjacent to a pair of coating removal blades. An interval between the pair of guides is fixed so as to be equivalent to the thickness of the optical fiber (for example, the diameter of a single core optical fiber or the thickness of a tape optical fiber). By supporting the optical fiber with the pair of guides, the optical fiber bare wire is prevented from coming into contact with the coating removal blade and being damaged therewith when the coating material is pulled out from the terminal portion of the optical fiber.[Patent Document 1] PCT International Publication No. WO2010/100912

In recent years, there are various types of optical fibers having different thicknesses of the optical fiber (for example, the thickness of the coating material covering the optical fiber bare wire). However, the above conventional optical fiber coating removal apparatus has poor workability and is not preferable, since an operator needs to exchange the pair of guides according to the thickness of the optical fiber. Although there is a method of making a mechanism capable of precisely adjusting the interval between the pair of guides, an expensive and complicated structure is required for such a mechanism.

SUMMARY

One or more embodiments of the present invention provide a coating removal blade, a removal blade unit, and an optical fiber coating removal apparatus that can inexpensively support and easily handle various types of optical fibers.

One or more embodiments of the present invention provide a coating removal blade used in an optical fiber coating removal apparatus configured to remove a coating material of an optical fiber, including a blade tip that is pressed against the coating material from a radial direction of an optical fiber bare wire of the optical fiber, and a pressing surface against which the coating material to be pulled out from the optical fiber is pressed in a longitudinal direction of the optical fiber, in which the pressing surface includes an inclined surface inclined at a constant angle so as to extend in a direction opposite to a pulling-out direction of the optical fiber as a distance from the blade tip in the radial direction of the optical fiber bare wire increases, and an inclination angle of the inclined surface with respect to the pulling-out direction of the optical fiber is larger than 0° and equal to or smaller than 60°.

One or more embodiments of the present invention provide a coating removal blade used in an optical fiber coating removal apparatus configured to remove a coating material of an optical fiber, including a blade tip that is pressed against the coating material from a radial direction of an optical fiber bare wire of the optical fiber, and a pressing surface against which the coating material to be pulled out from the optical fiber is pressed in a longitudinal direction of the optical fiber, in which the pressing surface includes an inclined surface inclined so as to extend in a direction opposite to a pulling-out direction of the optical fiber as a distance from the blade tip in the radial direction of the optical fiber bare wire increases, and the inclined surface is formed in a curved surface shape in which an inclination angle of the inclined surface with respect to the pulling-out direction of the optical fiber becomes smaller as a distance from the blade tip increases.

One or more embodiments of the present invention provide the coating removal blade in which the pressing surface includes a hook surface formed between the inclined surface and the blade tip, and the hook surface may be orthogonal to the pulling-out direction of the optical fiber or may be inclined so as to extend in the direction opposite to the pulling-out direction of the optical fiber as a distance to the blade tip from the inclined surface in the radial direction of the optical fiber bare wire decreases.

One or more embodiments of the present invention provide the coating removal blade further including a first blade-divided body including the inclined surface, and a second blade-divided body including the hook surface and the blade tip, in which the first blade-divided body and the second blade-divided body may be sequentially arranged in the pulling-out direction.

One or more embodiments of the present invention provide the coating removal blade in which a recess portion recessed in the pulling-out direction may be formed between the inclined surface and the hook surface of the pressing surface.

One or more embodiments of the present invention provide the coating removal blade in which the inclined surface is formed on an inner surface of a rotating body having the pulling-out direction as an axis, and an inner diameter of the inner surface of the rotating body may increase toward the direction opposite to the pulling-out direction from the blade tip.

One or more embodiments of the present invention provide a removal blade unit including a pair of the coating removal blades in which the inclined surfaces of the pair of coating removal blades face each other in an arrangement direction of the pair of coating removal blades while the optical fiber is sandwiched between the pair of coating removal blades from the radial direction of the optical fiber bare wire and an interval between the inclined surfaces of the pair of coating removal blades gradually decreases toward the pulling-out direction of the optical fiber.

One or more embodiments of the present invention provide the removal blade unit in which the inclination angles of the inclined surfaces of the pair of coating removal blades may be equal to each other.

One or more embodiments of the present invention provide an optical fiber coating removal apparatus including the removal blade unit according to one or more embodiments.

One or more embodiments of the present invention provide an optical fiber coating removal apparatus including the coating removal blade according to one or more embodiments.

According one or more embodiments of the present invention described above, it is possible to prevent the optical fiber bare wire from coming into contact with the blade tip of the coating removal blade when the optical fiber is pulled out from the coating material by using only the pair of coating removal blades. In addition, it is possible to deal with coating removal for various types of optical fibers having various thicknesses by setting the inclined surfaces of the pair of coating removal blades to face each other in the arrangement direction of the pair of coating removal blades. Therefore, it is possible to inexpensively deal with coating removal for various types of optical fibers having different thicknesses, while an operator can easily handle the optical fiber coating removal apparatus.

DETAILED DESCRIPTION

Hereinafter, one or more embodiments of an optical fiber coating removal apparatus will be described with reference toFIGS. 1 to 4.

The optical fiber coating removal apparatus of the first example of one or more embodiments removes a coating material at a terminal portion of an optical fiber (coated optical fiber). The optical fiber handled in the optical fiber coating removal apparatus may be a single core optical fiber or a tape optical fiber.

As shown inFIGS. 1 to 3, the optical fiber coating removal apparatus1(hereinafter referred to as a coating removal apparatus1) includes a removal blade unit2configured to remove a coating material101of an optical fiber100. The removal blade unit2includes a pair of coating removal blades3and3. When removing the coating material101, the pair of coating removal blades3and3sandwiches the optical fiber100from a radial direction of an optical fiber bare wire102(the vertical direction inFIG. 3).

In addition, the coating removal apparatus1is provided with a pulling-out mechanism to pull out the other portion of the optical fiber100relative to a coating material101A at the terminal portion while the optical fiber100is sandwiched between the pair of coating removal blades3and3.

Hereinafter, the overall configuration of the coating removal apparatus1of one or more embodiments will be specifically described.

The coating removal apparatus1of one or more embodiments includes, in addition to the pair of coating removal blades3and3, two clamp units4and5and a slide shaft6.

One of the two clamp units4and5is a first clamp unit4for sandwiching the terminal portion of the optical fiber100. The first clamp unit4includes a base11and a lid12. The base11and the lid12are coupled to each other such that the base11and the lid12can be opened and closed. By closing the lid12on the base11, the terminal portion of the optical fiber100can be sandwiched and held in the first clamp unit4. The terminal portion of the optical fiber100is brought into contact with facing surfaces13and14of the base11and the lid12, respectively, facing each other while the terminal portion of the optical fiber100is sandwiched by the first clamp unit4. Therefore, at least one of the facing surfaces13and14of the base11and the lid12may be made of a material having a high coefficient of friction with the terminal portion of the optical fiber100(coating material101A), such as rubber.

The pair of coating removal blades3and3is attached individually to the base11and the lid12of the first clamp unit4. The pair of coating removal blades3and3is disposed at an end portion of the first clamp unit4facing a second clamp unit5described later.

The other of the two clamp units4and5is the second clamp unit5for sandwiching the other portion of the optical fiber100(a portion adjacent to the terminal portion). The second clamp unit5includes a fiber holder15, a holder base16, and a holder lid17. The fiber holder15holds the other portion of the optical fiber100such that the other portion is clamped and is detachably provided to the holder base16. The holder base16is formed with a housing recess18that houses the fiber holder15. The housing recess18is formed so as not to open at an end portion of the second clamp unit5facing the first clamp unit4. The holder lid17is coupled to the holder base16such that the holder lid17can be opened and closed.

The fiber holder15holding the other portion of the optical fiber100is housed in the housing recess18of the holder base16and then, the holder lid17is closed on the holder base16such that the fiber holder15can be held within the housing recess18. With this, the other portion of the optical fiber100can be held in the second clamp unit5.

The slide shaft6is a guide for moving the two clamp units4and5only in a direction in which the above-mentioned two clamp units4and5are moved toward and away from each other in a longitudinal direction of the optical fiber100.

These two clamp units4and5and the slide shaft6constitute the aforementioned pulling-out mechanism.

In the coating removal apparatus1of one or more embodiments, for example, a heater (not shown) for heating the coating material101A at the terminal portion of the optical fiber100may be provided on, for example, one or both of the base11and the lid12of the first clamp unit4.

In the coating removal apparatus1described above, the coating material101A of the optical fiber100can be removed as follows.

First, the terminal portion of the optical fiber100is held by the first clamp unit4, while the other portion of the optical fiber100is held by the second clamp unit5. By holding the terminal portion of the optical fiber100in the first clamp unit4, it is possible to sandwich the optical fiber100from the radial direction of the optical fiber bare wire102with the pair of coating removal blades3and3as shown inFIG. 3.

Thereafter, as shown inFIG. 4, by moving the second clamp unit5in a direction away from the first clamp unit4(a pulling-out direction D1of the optical fiber100), the portion of the coating material101sandwiched between the pair of coating removal blades3and3is cut off. With this, the optical fiber100can be pulled out relative to the coating material101A held by the first clamp unit4.

In the case where the coating removal apparatus1includes a heater, by heating the coating material101A at the terminal portion with the heater while the terminal portion of the optical fiber100is held in the first clamp unit4, an adhesion force between the coating material101A and the optical fiber bare wire102can be reduced. Accordingly, when the second clamp unit5is moved with respect to the first clamp unit4, the optical fiber100can be pulled out from the coating material101A with ease.

Next, the shape of the coating removal blade3according to one or more embodiments will be described.

As shown inFIGS. 2 to 4, the coating removal blade3has a blade tip21and a pressing surface22. The blade tip21is a portion that is pressed against the coating material101from the radial direction of the optical fiber bare wire102when the optical fiber100is sandwiched between the pair of coating removal blades3and3.

The pressing surface22is a surface against which the coating material101A to be pulled out from the optical fiber100is pressed in the longitudinal direction of the optical fiber100when the optical fiber100is pulled out relative to the coating material101A. In other words, the pressing surface22is a surface against which the coating material101A to be removed from the optical fiber100is pressed when the optical fiber100is pulled out relative to the coating material101A at the terminal portion in a state where the optical fiber100is sandwiched between the pair of coating removal blades3and3. The pressing surface22is a surface facing a direction opposite to the pulling-out direction D1of the optical fiber100(the right direction inFIG. 2).

The pressing surface22includes an inclined surface23. The inclined surface23is a surface inclined so as to extend in a direction opposite to the pulling-out direction D1of the optical fiber100as the distance from the blade tip21of the coating removal blade3in the radial direction of the optical fiber bare wire102(the downward direction inFIG. 2) increases.

An inclination angle θA of the inclined surface23with respect to the pulling-out direction D1of the optical fiber100is larger than 0° and equal to or smaller than 60°. Alternatively, the inclination angle θA of the inclined surface23may be, for example, 45° or smaller, or may be 30° or smaller. Alternatively, the inclination angle θA of the inclined surface23may be, for example, 20° or smaller.

The inclined surface23of one or more embodiments is inclined at a constant angle at which the inclination angle θA does not change in an inclined direction thereof. That is, the inclined surface23of one or more embodiments is formed linearly when viewed from the direction shown inFIGS. 2 to 4.

In the removal blade unit2including the pair of coating removal blades3and3, the inclined surfaces23and23of the pair of coating removal blades3and3face each other in the arrangement direction of the pair of coating removal blades3and3(the vertical direction inFIG. 3) while the optical fiber100is sandwiched between the pair of coating removal blades3and3. In addition, an interval between this pair of inclined surfaces23and23gradually decreases toward the pulling-out direction D1of the optical fiber100. The inclination angles θA of the pair of inclined surfaces23and23may be equal to each other but may also be slightly different, for example.

In the coating removal blade3including the inclined surface23, the position of a first end25of the inclined surface23located furthest from the blade tip21in the radial direction of the optical fiber bare wire102(the vertical direction inFIG. 2) with respect to the blade tip21can be arbitrary.

The position of the first end25of the inclined surface23with respect to the blade tip21may be set such that, for example, in a state where the optical fiber100is sandwiched between the pair of coating removal blades3and3, a distance between the first ends25and25of the inclined surfaces23and23of the pair of coating removal blades3and3in the arrangement direction of the pair of coating removal blades3and3is larger than a thickness t1of the optical fiber100(the diameter of the single core optical fiber or the thickness of the tape optical fiber). In this case, when the optical fiber100is pulled out relative to the coating material101A, the coating material101A to be pulled out from the optical fiber100can be prevented from being pushed against a surface other than the pressing surface22, for example, a vertical surface31connected to the first end25of the inclined surface23(a surface extending in the radial direction of the optical fiber bare wire102).

A distance from the blade tip21to the first end25of the inclined surface23in the radial direction of the optical fiber bare wire102(the vertical direction inFIG. 3) is larger than a thickness t2of the coating material101of the optical fiber100of a type having, for example, the largest thickness of the coating material101.

The pressing surface22of one or more embodiments also includes the hook surface24in addition to the inclined surface23described above. The hook surface24is formed between the inclined surface23and the blade tip21.

For example, the hook surface24may be inclined so as to extend in the direction opposite to the pulling-out direction D1of the optical fiber100as a distance from the blade tip21of the coating removal blade3in the radial direction of the optical fiber bare wire102(the downward direction inFIG. 2) increases. That is, an inclination angle θB of the hook surface24with respect to the pulling-out direction D1of the optical fiber100may be, for example, larger than 90°.

The hook surface24of one or more embodiments is orthogonal to the pulling-out direction D1of the optical fiber100. The inclination angle θB of the hook surface24orthogonal to the pulling-out direction D1may be 90° or an angle slightly deviated from 90° (desirably in the range of 80° to 120°.

In one or more embodiments, the hook surface24extends from the blade tip21to the inclined surface23. Specifically, a first end27of the hook surface24is directly connected to the blade tip21. A second end28of the hook surface24is directly connected to a second end26of the inclined surface23located closest to the blade tip21in the radial direction of the optical fiber bare wire102.

The hook surface24functions as a surface against which a portion of the coating material101A to be pulled out from the optical fiber100on a side close to the optical fiber bare wire102in the radial direction of the optical fiber bare wire102(an inner portion of the coating material101A) is pressed when the optical fiber100is pulled out relative to the coating material101A.

Therefore, the dimension of the hook surface24in the radial direction of the optical fiber bare wire102(a distance from the first end27to the second end28of the hook surface24in the radial direction of the optical fiber bare wire102(the vertical direction inFIG. 2)) is smaller than at least the thickness t2of the coating material101covering the optical fiber bare wire102. In addition, the dimension of the hook surface24in the radial direction of the optical fiber bare wire102is set such that the second end28of the hook surface24is located inside the coating material101, compared to an outer surface of the coating material101while the blade tip21bites into the coating material101as shown inFIG. 3.

For example, when the thickness t1of the optical fiber100(the diameter of the single core optical fiber or the thickness of the tape optical fiber) of a type having the smallest thickness is 200 μm, the dimension of the hook surface24in the radial direction of the optical fiber bare wire102is set to be smaller than, for example, 100 μm.

The blade tip21of the coating removal blade3may be, for example, pointed but, in one or more embodiments, is formed in a flat shape extending in the pulling-out direction D1of the optical fiber100. The length of the blade tip21in the pulling-out direction D1of the optical fiber100is set to such a degree that the blade tip21can bite into the coating material101when the optical fiber100is sandwiched between the pair of coating removal blades3and3.

Since the blade tip21is formed flat, it is possible to ensure the strength of a tip portion of the coating removal blade3including the blade tip21and the hook surface24and to suppress chipping of the tip portion. Additionally, compared with a case where the blade tip21is pointed, it is possible to suppress that the blade tip21excessively bites into the coating material101until reaching the optical fiber bare wire102. That is, it is possible to prevent the optical fiber bare wire102from being damaged by the coating removal blade3.

Meanwhile, a surface29(opposite surface29) of the coating removal blade3connected to a side opposite to the above-described pressing surface22with respect to the blade tip21may be, for example, orthogonal to the pulling-out direction D1of the optical fiber100. In one or more embodiments, however, the surface29is inclined in a direction gradually away from the blade tip21in the radial direction of the optical fiber bare wire102toward the pulling-out direction D1of the optical fiber100. Since the opposite surface29is inclined, the strength of the tip portion of the coating removal blade3can be further ensured and chipping of the tip portion can be further suitably suppressed.

In addition, the coating removal blade3in one or more embodiments is a flat blade extending in one direction orthogonal to the pulling-out direction D1of the optical fiber100(a direction orthogonal to the paper surface inFIGS. 2 to 4). The inclined surface23, the hook surface24, the blade tip21, and the opposite surface29of the coating removal blade3are formed on a surface extending in the above-mentioned one direction and are flat.

Next, the action of the coating removal blade3of one or more embodiments configured as described above will be described.

The coating removal blade3of one or more embodiments has the inclined surface23. Therefore, as shown inFIG. 3, while the optical fiber100is sandwiched between the pair of coating removal blades3and3, the inclined surfaces23and23of the pair of coating removal blades3and3face each other in the arrangement direction of the pair of coating removal blades3and3. In addition, the interval between the pair of inclined surfaces23and23gradually decreases toward the pulling-out direction D1of the optical fiber100. Therefore, as shown inFIG. 4, when the optical fiber100is moved in the pulling-out direction D1, the coating material101A located between the pair of inclined surfaces23and23is pressed in a direction of approaching the center of the optical fiber bare wire102in the arrangement direction of the pair of coating removal blades3and3. At this time, the coating material101A between the pair of inclined surfaces23and23is compressively deformed. The fact that the coating material101A between the pair of inclined surfaces23and23is pressed toward the center of the optical fiber bare wire102makes it possible to prevent the optical fiber bare wire102from approaching one of the blade tips21of the coating removal blades3. That is, it is possible to prevent the optical fiber bare wire102from coming into contact with the blade tip21of the coating removal blade3.

Meanwhile, the coating removal blade3of one or more embodiments has the hook surface24. Therefore, as shown inFIG. 3, the hook surface24of each coating removal blade3is positioned so as to overlap with the coating material101A between the pair of inclined surfaces23and23in the pulling-out direction D1of the optical fiber100while the optical fiber100is sandwiched between the pair of coating removal blades3and3and the blade tip21bites into the coating material101. Here, the hook surface24is orthogonal to the pulling-out direction D1of the optical fiber100. Therefore, as shown inFIG. 4, when the optical fiber100is moved in the pulling-out direction D1, the coating material101A between the pair of inclined surfaces23and23is pressed against the hook surface24. With this, it is possible to prevent the coating material101A compressed by the pair of inclined surfaces23and23from passing through between the pair of coating removal blades3and3.

Even when the hook surface24is, for example, not orthogonal but inclined as described above, the coating material101A compressed by the pair of inclined surfaces23and23can be similarly prevented from passing through between the pair of coating removal blades3and3.

As described thus far, according to the coating removal blade3of one or more embodiments and the removal blade unit2and the coating removal apparatus1including the coating removal blade3, the pressing surface22of the coating removal blade3includes the inclined surface23. Therefore, when the optical fiber100is pulled out from the coating material101A at the terminal portion using only the pair of coating removal blades3and3without providing a guide as in the past, it is possible to prevent the optical fiber bare wire102from coming into contact with the blade tip21of the coating removal blade3. Additionally, since the inclined surfaces23and23of the pair of coating removal blades3and3face each other in the arrangement direction of the pair of coating removal blades3and3, it is possible to deal with coating removal for various types of the optical fibers100having various thicknesses. Consequently, it is possible to inexpensively deal with coating removal for various types of the optical fibers100having different thicknesses, while an operator can easily handle the coating removal apparatus1.

Furthermore, in a case where the inclination angles θA of the inclined surfaces23and23of the pair of coating removal blades3and3are equal to each other, the following effects are achieved in the removal blade unit2of one or more embodiments. When the optical fiber100is pulled out from the coating material101A in a state where the optical fiber100is sandwiched between the pair of coating removal blades3and3, a force received by the coating material101A located between the pair of inclined surfaces23and23from the inclined surface23becomes equal between the pair of inclined surfaces23and23. This makes it possible to more reliably prevent the optical fiber bare wire102from approaching one of the blade tips21of the coating removal blades3when the optical fiber100is pulled out from the coating material101A. That is, it is possible to more reliably prevent the optical fiber bare wire102from coming into contact with the blade tip21of the coating removal blade3.

Meanwhile, in the coating removal blade3of one or more embodiments, the inclination angle θA of the inclined surface23is larger than 0°. With this, when the optical fiber100is pulled out relative to the coating material101A, the coating material101A to be pulled out from the optical fiber100can be pressed against the inclined surface23in the pulling-out direction D1of the optical fiber100.

Besides, in the coating removal blade3of one or more embodiments, the inclination angle θA of the inclined surface23is equal to or smaller than 60°. This makes it possible to prevent an insufficient force of pressing the coating material101A located between the pair of inclined surfaces23and23toward the optical fiber bare wire102when the optical fiber100is pulled out relative to the coating material101A. Therefore, it is possible to suitably prevent the optical fiber bare wire102from approaching and contacting one of the blade tips21of the coating removal blades3.

In addition, when the inclination angle θA of the inclined surface23is further reduced from 60° (for example, in the case of 45° or smaller, 30° or smaller, and 20° or smaller), a force of pressing the coating material101located between the pair of inclined surfaces23and23against the optical fiber bare wire102can be increased. Consequently, it is possible to more reliably prevent the optical fiber bare wire102from coming into contact with one of the blade tips21of the coating removal blades3.

Additionally, in the coating removal blade3of one or more embodiments, the pressing surface22also includes the hook surface24. Therefore, it is possible to prevent the coating material101A compressed by the pair of inclined surfaces23and23from passing through between the pair of coating removal blades3and3when the optical fiber100is pulled out from the coating material101A. That is, it is possible to prevent the coating material101A to be removed, from remaining on the optical fiber bare wire102at the terminal portion.

Next, one or more embodiments of the optical fiber coating removal apparatus will be described with reference toFIGS. 5 and 6, focusing on differences from one or more embodiments described above. Note that the same reference numerals are attached to configurations common to one or more embodiments described above and the description thereof will be omitted.

As shown inFIGS. 5 and 6, coating removal blades3A and3B of one or more embodiments have pressing surfaces22A and22B including inclined surfaces23A and23B and hook surfaces24A and24B, and blade tips21A and21B, respectively.

However, the inclined surfaces23A and23B according to one or more embodiments are formed on a conical inner surface (an inner surface of a rotating body) having the pulling-out direction D1of an optical fiber100as an axis. The inner diameter of the conical inner surface becomes larger toward the direction opposite to the pulling-out direction D1of the optical fiber100from the blade tips21A and21B.

The hook surfaces24A and24B according to one or more embodiments are formed on a fan-shaped surface having the pulling-out direction D1of the optical fiber100as an axis, similarly to the inclined surfaces23A and23B.

InFIGS. 5 and 6, the inclined surfaces23A and23B and the hook surfaces24A and24B are formed in a shape obtained by rotating by 180° about the axis of the pulling-out direction D1of the optical fiber100. However, these surfaces can be formed in a shape obtained by rotating by any angle (for example, an angle smaller than 180°).

In the coating removal blade3A exemplified inFIG. 5, the blade tip21A is formed by linearly extending in one direction orthogonal to the pulling-out direction D1of the optical fiber100(a direction denoted by reference numeral D2inFIG. 5), similarly to the blade tip21of one or more embodiments.

In the coating removal blade3B shown inFIG. 6, the blade tip21B is formed in an arc concave shape having the axis of the conical inner surface as the center. In this case, the optical fiber100fits into the blade tip21B having a concave shape such that the blade tip21B bites into a coating material101when the optical fiber100is sandwiched between the pair of coating removal blades3B and3B.

In the coating removal blades3A and3B of one or more embodiments described above, a sectional shape passing through the axis of the conical inner surface can be a shape similar to the shape of the coating removal blade3of one or more embodiments exemplified inFIGS. 2 to 4.

The coating removal blades3A and3B of one or more embodiments achieve effects similar to those of one or more embodiments described above.

Additionally, in the coating removal blades3A and3B of one or more embodiments, the inclined surfaces23A and23B are formed on the conical inner surface (the inner surface of the rotating body) having the pulling-out direction D1of the optical fiber100as the axis. Therefore, when the optical fiber100is moved in the pulling-out direction D1in a state where the optical fiber100is sandwiched between the pair of coating removal blades3A and3A (3B and3B), a coating material101A located between the inclined surfaces23A and23A (23B and23B) of the pair of coating removal blades3A and3A (3B and3B) can be pressed in a direction of approaching the center of an optical fiber bare wire102in the radial direction of the optical fiber bare wire102. In other words, the coating material101A located between the pair of inclined surfaces23A and23A (23B and23B) can be pressed toward the center of the optical fiber bare wire102not only from the arrangement direction of the pair of coating removal blades3A and3A (3B and3B) but also from a direction orthogonal to the pulling-out direction D1of the optical fiber100and intersecting the arrangement direction of the pair of coating removal blades3A and3A (3B and3B). Thus, it is possible to more reliably prevent the optical fiber bare wire102from approaching one of the blade tips21A and21B of the coating removal blades3A and3B. That is, it is possible to more reliably prevent the optical fiber bare wire102from coming into contact with the blade tips21A and21B of the coating removal blades3A and3B.

Next, one or more embodiments of the optical fiber coating removal apparatus will be described with reference toFIG. 7, focusing on differences from one or more embodiments described above. Note that the same reference numerals are attached to configurations common to one or more embodiments described above and the description thereof will be omitted.

As shown inFIG. 7, a coating removal blade3C of one or more embodiments has a pressing surface22C including an inclined surface23C and a hook surface24, and a blade tip21of one or more embodiments.

However, the inclined surface23C of one or more embodiments is formed on a surface whose inclination angle changes in an inclined direction thereof. Specifically, the inclined surface23C is formed in a curved surface shape in which the inclination angle θA of the inclined surface23C with respect to the pulling-out direction D1decreases as the distance from the blade tip21increases.

The inclined surface23C as viewed from the direction shown inFIG. 7may be formed in, for example, a curved shape forming a part of an ellipse as exemplified inFIG. 7, or may be formed in, for example, a curved shape forming a part of a circle.

The inclination angle θA of the inclined surface23C formed in the curved surface shape may be larger than 0° and equal to or smaller than 60° throughout the entire inclined surface23C in the inclined direction (a longitudinal direction of a curve inFIG. 7). However, the inclination angle θA is not limited to this. The inclination angle θA of the inclined surface23C is only required to be larger than 0° and equal to or smaller than 60° at least in a part of the inclined surface23C in the inclined direction. The inclination angle θA of the inclined surface23C at a first end25of the inclined surface23C may be 0°, for example. Meanwhile, the inclination angle θA of the inclined surface23C at a second end26of the inclined surface23C may be larger than 60°, for example.

In one or more embodiments, the inclined surface23C can be formed on, for example, a surface extending in one direction orthogonal to the pulling-out direction D1of the optical fiber100(a direction orthogonal to the paper surface inFIG. 7), as in the case of one or more embodiments described above. In addition, the inclined surface23C may be formed on, for example, an inner surface of a spherical body (the inner surface of the rotating body) having the pulling-out direction D1of the optical fiber100as an axis, as in the case of one or more embodiments described above. The inner surface of the spherical body can include an inner surface of an ellipsoid or an inner surface of a sphere.

The coating removal blade3C of one or more embodiments achieves effects similar to those of one or more embodiments described above.

Next, one or more embodiments of the optical fiber coating removal apparatus will be described with reference toFIG. 8, focusing on differences from one or more embodiments described above. Note that the same reference numerals are attached to configurations common to one or more embodiments described above and a description thereof will be omitted.

As shown inFIG. 8, a coating removal blade3D of one or more embodiments has a pressing surface22including an inclined surface23and a hook surface24, and a blade tip21as in one or more embodiments described above.

However, the coating removal blade3D of one or more embodiments includes two blade-divided bodies41D and42D. The first blade-divided body41D includes the inclined surface23of the pressing surface22. Meanwhile, the second blade-divided body42D includes the hook surface24of the pressing surface22and the blade tip21. The first blade-divided body41D and the second blade-divided body42D are sequentially arranged in the pulling-out direction D1of an optical fiber100.

In one or more embodiments, the respective two blade-divided bodies41D and42D are formed so as to be in surface contact with each other. In the coating removal blade3D exemplified inFIG. 8, contact surfaces43D and44D of the blade-divided bodies41D and42D, respectively, which are in surface contact with each other are orthogonal to the pulling-out direction D1of the optical fiber100, but the contact surfaces43D and44D are not limited to this.

The contact surfaces43D and44D of the two blade-divided bodies41D and42D may be formed, for example, flatly but may be formed in, for example, a concavo-convex shape such that the contact surfaces43D and44D mesh with each other. In this case, the two blade-divided bodies41D and42D can be easily positioned relative to each other.

Additionally, in one or more embodiments, the height dimensions of the two blade-divided bodies41D and42D in the radial direction of an optical fiber bare wire102(the vertical direction inFIG. 8) are made different from each other. In this case, only by aligning the positions of lower ends (ends opposite to the blade tips21) of the two blade-divided bodies41D and42D, the blade tip21and a second end26of the inclined surface23can be easily positioned relative to each other in the radial direction of the optical fiber bare wire102.

The coating removal blade3D of one or more embodiments achieves effects similar to those of one or more embodiments described above.

Furthermore, the coating removal blade3D of one or more embodiments includes the first blade-divided body41D including the inclined surface23, and the second blade-divided body42D including the hook surface24and the blade tip21. Therefore, by merely replacing one of the two blade-divided bodies41D and42D, the relative positional relationship between the inclined surface23and the hook surface24, and the sizes and the inclination angles θA and θB (refer toFIG. 2) of the inclined surface23and the hook surface24can be adjusted with ease.

In addition, even if a part of the coating removal blade3D (for example, only in the inclined surface23, or only in the hook surface24) is damaged or becomes unusable, either one of the two blade-divided bodies41D and42D only needs to be replaced and accordingly, maintenance of the coating removal blade3D can be easily performed.

Meanwhile, since the shapes of the respective two blade-divided bodies41D and42D can be simplified, compared with the shape of the entire coating removal blade3D, the coating removal blade3D can be easily manufactured.

The configuration of one or more embodiments described above can also be applied to the coating removal blades3A,3B, and3C.

Next, one or more embodiments of the optical fiber coating removal apparatus will be described with reference toFIGS. 9 and 10, focusing on differences from one or more embodiments described above. Note that the same reference numerals are attached to configurations common to one or more embodiments described above and the description thereof will be omitted.

As shown inFIGS. 9 and 10, each of the coating removal blades3E and3F of one or more embodiments has a pressing surface22including an inclined surface23and a hook surface24, and a blade tip21.

However, in each of the coating removal blades3E and3F according to one or more embodiments, a recess portion51recessed in the pulling-out direction D1of an optical fiber100is formed between the inclined surface23and the hook surface24of the pressing surface22.

The shape of an inner surface of the recess portion51can be arbitrary.

A first inner side surface52connected to a second end26of the inclined surface23on the inner surface of the recess portion51may extend, for example, in the pulling-out direction D1. In addition, as shown inFIGS. 9 and 10as an example, the first inner side surface52may be inclined at the same inclination angle θA as that of the inclined surface23and formed to be flush with the inclined surface23. In other words, for example, the first inner side surface52of the recess portion51may constitute a part of the inclined surface23.

A second inner side surface53that is connected to a second end28of the hook surface24on the inner surface of the recess portion51and faces the first inner side surface52may extend, for example, in the pulling-out direction D1as shown inFIGS. 9 and 10. In addition, the second inner side surface53may be inclined with respect to the pulling-out direction D1in such a manner that, for example, an interval to the first inner side surface52gradually increases toward an opening of the recess portion51(the right end of the recess portion51inFIGS. 9 and 10) from the bottom of the recess portion51(the left end of the recess portion51inFIGS. 9 and 10).

The first inner side surface52and the second inner side surface53of the recess portion51, for an example, may be connected directly at the bottom of the recess portion51as shown inFIG. 9, or alternatively, for example, may be positioned with an interval at the bottom of the recess portion51as shown inFIG. 10. The inner surface of the recess portion51exemplified inFIG. 10includes a bottom surface54connecting the first inner side surface52and the second inner side surface53at the bottom of the recess portion51.

The coating removal blades3E and3F of one or more embodiments achieve effects similar to those of one or more embodiments described above.

Additionally, in each of the coating removal blades3E and3F of one or more embodiments, the recess portion51is formed between the inclined surface23and the hook surface24. Therefore, when the optical fiber100is pulled out from a coating material101A in a state where the optical fiber100is sandwiched between the pair of coating removal blades3E and3E (3F and3F), the coating material101A compressed by the pair of inclined surfaces23and23in a direction of approaching the center of an optical fiber bare wire102is likely to enter the recess portion51. It is thus possible to more reliably prevent the coating material101A compressed by the pair of inclined surfaces23and23from passing through between the pair of coating removal blades3E and3E (3F and3F). That is, it is possible to more reliably prevent the coating material101A to be removed, from remaining on the optical fiber bare wire102.

The configuration of one or more embodiments described above can also be applied to the coating removal blades3A,3B,3C, and3D of any of the above-described embodiments.

Although the disclosure has been described with respect to only a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciated that various other embodiments may be devised without departing from the scope of the present invention. Accordingly, the scope of the invention should be limited only by the attached claims.

For example, in the coating removal blade, the pressing surface22may not include the hook surface24, as exemplified by coating removal blades3G,3H, and3I shown inFIGS. 10 to 12. That is, the pressing surface22is only required to include at least the inclined surface23.

In addition, in the coating removal blade, the blade tip21may be formed in a pointed shape instead of being flat, as exemplified by the coating removal blades3H and3I shown inFIGS. 11 and 12.

Furthermore, in the coating removal blade, the opposite surface29facing away from the pressing surface22may not be inclined as exemplified by the coating removal blade3I shown inFIG. 12and may be orthogonal to the pulling-out direction D1of the optical fiber100.

DESCRIPTION OF THE REFERENCE SYMBOLS

1: Optical fiber coating removal apparatus

2: Removal blade unit

3,3A,3B,3C,3D,3E,3F,3G,3H,3I: Coating removal blade

21,21A,21B: Blade tip

22,22A,22B,22C: Pressing surface

24,24A,24B: Hook surface

100: Optical fiber

101,101A: Coating material

102: Optical fiber bare wire

θA: Inclination angle of inclined surface