JPS61142062A - Method and device for polishing ferrule end face of optical connector - Google Patents

Abstract

PURPOSE:To stably carry out end face polishing with high accuracy by bringing a ferrule in pressure contact with the top face of a rotary polishing disk while being minutely inclined, and making it alternately rotate on its own axis in both normal and reverse directions, within a range of defined rotation angle, to carry out end face polishing. CONSTITUTION:First, a polishing disk 41 is rotated, a ferrule 60 is inserted into the inserting hole 43a of a small diameter gear 43, the notched part 60c of its flange part 60b is engaged with an engaging pin 43c, and the end face 60a is brought in pressure contact with the top face 41a of the rotary polishing disk 41 with a proper pressing force. The ferrule 60 is set at a minute inclination angle beta by means of a retainer board 44. Then, the retainer board 44 is normally rotated and reversed alternately by means of a driving shaft 44 and, synchronized with this, the small diameter gear 43 is turned on an inside diameter gear 42 while rotating on its own axis to polish the end face 60a. Accordingly, stable and highly accurate end face polishing can be carried out by setting a ferrule in a small gear merely one time, reducing manhour for polishing.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to optical connectors for optically connecting optical fibers in devices such as optical communication devices, and in particular to components of optical connectors. The present invention relates to a method for polishing the end face of a ferrule that incorporates an optical fiber along its axis, and a polishing device therefor.

As an optical connector, two ferrules with optical fibers built in along the axis z are used, and these are inserted into the sleeve at both ends, and the end faces of the ferrules are butted against each other, and the end faces of the optical fibers are brought into contact with each other. An end-face butting type optical connector is often used, in which each ferrule is tightened and fixed within a sleeve using a cap nut or the like. This species,
In the case of two-way optical connectors, first, the surface angle of the mating end faces of the ferrules relative to the optical axis changes directly to the optical close reading loss of the optical fiber. For example, as shown in Fig. 8, the end face 11-12 of the ferrule 11-1 is ground with an angle of perpendicularity of α to the perpendicular end face °2).
[In many cases, the work is difficult. The reason for this is due to the Pl field of the polishing device and the Tsushiro type Yu' accumulation.

The ferrule 11-1 whose end face has been polished in this way is
As shown in FIG. 7, when inserted into the sleeve 13 and abutted against the end face 11-22 of the other D ferrule 11-2, both optical fibers 12. Before 1 and 12-2 are brought into contact, the - portions of the ferrule end faces 1tla and 11-22 are brought into contact with each other in advance to form a gap G between the end faces of the optical fibers 121 and 12-2. That will happen. In reality, this gap G tends to vary in size due to variations in the end face polishing accuracy. Such a change in the gap G causes multiple reflections of light between the end faces of the optical fibers 12-1 and 12-2, causing a light interference phenomenon.
A problem arises in that the fluctuation range of optical connection loss is very large, making it impossible to obtain efficient and stable connection performance.

In other words, at the value of the gap G, which is 1 depending on related factors such as the wavelength (λ) of the optical signal to be transmitted, the light beams weaken each other due to the optical interference effect due to multiple reflections, resulting in a very large connection loss. At other gap G values that are close to this gap G value with a small difference, the light beams strengthen each other and the connection loss becomes extremely small! L.

Also, if the value of the gap G becomes very large, for example 8
When the thickness exceeds about 10 μm, the fluctuation width of the tangent Vt loss becomes very small and becomes stable, but on the other hand, a problem arises in that the connection efficiency decreases. Therefore, a method and apparatus for polishing the end face of a ferrule have been developed to solve these problems, and good results have been obtained. However, the following problems still exist, and countermeasures are desired.

[Conventional technology]

Fig. 4 is a side view showing the main parts of a first conventional ferrule end polishing device, Fig. 5 is a side view showing the main parts of a second conventional ferrule end face polishing method, and Fig. 6 shows that the end face has a convex shape. A partial perspective view of the ferrule 25-1 polished into a pyramidal shape, FIG.
A) is a partial perspective view of the ferrule 25-2 polished so that the end face has a band-shaped protrusion, and FIG. 7(B) is a plan view of the ferrule 25-2 viewed from direction C in FIG. 7(A). be.

The first conventional example shown in FIG. 4 basically consists of a rotating polishing plate 21 whose upper surface is formed in a convex circular shape with an angle β with respect to a horizontal plane, and a rotating polishing plate 21 for holding and fixing a ferrule 25. It has a ferrule holding plate 22. The ferrule 25 is held fixed so that its axis vAB is parallel to the rotational axis A of the rotary polishing plate 21, and its end surface 25a is parallel to the rotation axis A of the rotary polishing plate 21.
The rotary polishing plate 2 is pressed onto the two surfaces 2Ia with an appropriate pressing force.
The end surface 25a is polished into an inclined surface having an angle of β with respect to a plane perpendicular to the axis 13 by the rotational movement of 1 (in this case, in the direction indicated by the arrow ■). Therefore, the ferrule 25 is rotated by 90 degrees around its axis B to hold the fixed state for a total of 4 times.
By polishing at different times, the ferrule 25-1 becomes a ferrule 25-1 whose ferrule 1 side 25b is polished into a convex quadrangular pyramidal end surface, as shown in FIG.
As shown in FIG. 7, the ferrule 25-2 is polished into a shape in which the end surface 25c has a band-shaped convex portion 25d in the radial direction, as shown in FIG. Become. Note that reference numeral 26 in FIGS. 6 and 7 indicates an optical fiber built in along the axis of each of the ferrules 25-1 and 25-2.

The second conventional example shown in FIG. 5 basically consists of a rotating polishing plate 31 whose upper surface is formed into a flat surface, and a rotating disc-shaped ferrule holding plate for holding and fixing the ferrule 25 at an angle. 32. Ferrule 25 is the III
The line B is held and fixed at an inclination angle β with respect to the axis (vertical line) A of the rotary polishing plate 31, and its end surface 25a is pressed against the upper surface 3Ia2 of the rotary polishing plate 31 with an appropriate pressing force. The rotational movement of 31 (in this case, in the direction of the arrow) and the rotational speed of 32 (ferrule presser) (in this case,
The end surface 25a is polished into an inclined surface having an angle β with respect to a plane perpendicular to the axis B by the rotating polishing plate 31 and the opposite direction of the arrow E. Therefore, the 25th ferrule is polished by rotating it by 90° around its axis 8 and changing the holding identification state a total of 4 times, just as in the case of the first conventional example (Fig. 4). As shown in Fig. 6, the end face 25-b becomes a ferrule 25-1 polished into a convex quadrangular pyramidal end face, and the ferrule 25-1 rotates around the axis B by 180 degrees to change the holding and fixed state twice in total. As shown in FIG. 7, the ferrule 25-2 is polished into a shape in which the end surface 25C has a band-shaped convex portion 25d in the radial direction.

In the case of the ferrule 25-1 (FIG. 6) whose end face has been polished in this manner, only the end face of the optical fiber 26 at the tip and its surrounding area are butted together, so there is almost no gap between the end faces of the optical fiber 26. A good optical connector with low connection loss can be constructed. In the case of the ferrule 25-2 (Fig. 7), the 11-shaped convex portions 25d are butted against each other in a 11-shape (cross shape) to connect for the same reason as in the case of the ferrule 25-1. A good optical connector with low loss can be constructed.

[Problems that inventions are unlikely to solve]

The first conventional example (Fig. 4) and the second conventional example (Fig. 5) of the above configuration.
(Fig.), it is necessary to change the holding and fixing cent of the ferrule 25 by 180" twice in total or by 906" in total four times, or more times as necessary, so it is time-consuming to set up the polishing work. Therefore, there is a problem that the number of man-hours required for polishing the ferrule end face is large, resulting in a problem that the manufacturing cost increases.The present invention was devised for the purpose of solving this problem.

[Means for solving problems]

The present invention provides a method and apparatus for polishing the A11 surface of a ferrule of an optical connector that solves the above-mentioned problems. In the method, a disc-shaped rotary polishing plate having a flat upper surface is rotated, and the end face is tilted toward the polishing plate while the ferrule is inclined by a very small amount with respect to the vertical force direction of the upper surface of the rotary polishing plate. A method for polishing an end face of a ferrule of an optical connector is provided, in which the end face of an optical connector is polished while the ferrule is held in pressure contact with an upper surface and rotated in forward and reverse directions within a predetermined rotation angle range.

Further, according to the present invention, in a device for polishing the end face of a ferrule in which an optical fiber is built in along the axis, a rotating disc-shaped polishing plate having a flat upper surface is arranged horizontally, and the polishing plate is arranged horizontally. A large-diameter gear is arranged and fixed horizontally on the upper side, a small-diameter l'll wheel is arranged to mesh with the large-diameter gear, and a ferrule retainer is arranged horizontally. is rotatably supported, and its distal end is connected to the large diameter 1.
'J: +Fixed to the drive shaft concentrically and hanging down, 1)
11. Insert a ferrule into the center of the small diameter float from above and press its end surfaces against the two surfaces of the polishing plate to form a small diameter 1゛h.
A large 1l Ti hole is formed in the ferrule for fixing it in the circumferential direction, and the ferrule is made rotatable at the tip of the ferrule presser ◇; corresponding to the insertion hole of the small diameter gear) ff
i and press the ferrule in the horizontal direction to form an insertion hole for tilting the ferrule by a small amount. Provided is a ferrule end face polishing device for an optical connector configured to rotate the ferrule itself alternately in forward and reverse directions within a predetermined rotation angle range by moving a small gear in the circumferential direction of a large diameter gear. .

[For production]

The above-mentioned method for polishing the 7:jj surface of the ferrule and the polishing apparatus thereof include a method for polishing the 7:jj surface of the ferrule and a polishing apparatus thereof, in which the ferrule is tilted by a very small amount with respect to the vertical direction of the upper surface of the rotary polishing dish, and its end face is pressed against the upper surface of the rotary polishing dish, thereby polishing the ferrule to a small diameter. The end face can be polished while inserting and fixing the ferrule into the gear and rotating the ferrule itself alternately in the forward and reverse directions at a predetermined rotation angle, so the end face can be polished into a convex conical shape just by setting the ferrule once. Can be polished to a finish.

〔Example〕

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

FIG. 1 is a diagram showing a main part of an embodiment of the present invention, and (
A) is a side view thereof, (B) is a plan view seen from the direction of arrow EllC in (A), FIG. The figure is a diagram showing a state in which ferrules whose end faces are polished into convex conical shapes are butted against each other according to this embodiment. When looking at Figures 1 and 2, the left-hand side is the front side of the device 40 and other parts, the right-hand side is the rear side, and the left-hand side and right-hand side when looking from the front side to the rear side are the left side, respectively. and call it the right side.

In this embodiment, basically, as shown in FIGS. 1 and 2, a rotary polisher 41 in which the "-face/11a is formed as a flat surface.
, an internal gear (large diameter gear) 42 arranged and fixed on two sides of this polishing plate 41, and internal teeth 42a of this internal gear 42.
A small diameter gear 4 which is disposed in mesh with the gear and has a ferrule insertion hole 43a in the center thereof into which the ferrule 60 is inserted.
3, and is arranged between the small diameter 1h wheel 43 and the rotating polishing plate 41, and has a small diameter by its tip. It rotatably supports an Iir wheel 43 from below, and has a ferrule holding plate 44 whose base end hangs down from above and is fixed to a drive shaft 45 disposed concentrically with the internal gear 42. It consists of Second
As shown in the figure, the device main body 46 includes a base plate 46a and a base plate 4.
An upright plate 46b stands upright from the upright plate 46b, a front support plate 46c and a support arm 46d project forward from the upright plate 46b, and a rear support plate 4Ge projects rearward from the upright plate 461).
A window hole 46f is provided in the upper part of the upright plate 46b through T''.Bed plate 46a
A drive motor 47 is arranged on the front upper surface. Rotary polisher 4
1 is fixed to the drive shaft 47a of the motor 47, and in this case, is driven to rotate in the direction of the arrow (counterclockwise). The internal gear 42 is fitted and fixed to the front part of the front support plate 46c.

The small diameter gear 43 has a ferrule insertion hole 43a formed in its center, and a ferrule insertion hole 43a is formed in the center thereof. It is disposed in mesh with the I+l wheel 42, and is rotatably supported from below by a ferrule holding plate 44, as will be described later. Ferrule holding plate 44
is arranged below the small diameter gear 43, and an insertion hole 44a for rotatably pushing the ferrule 6o through is formed at its tip, corresponding to the insertion hole 43a of the small diameter gear 43, and an insertion hole 44a for rotatably pushing the ferrule 6o through. An annular support portion 44 provided around 44a
b (FIG. 1) is slidably fitted into an annular fitting portion 43b (FIG. 1) provided on the lower side of the small diameter gear 43 to rotatably support the small diameter gear 43 from below. . A base end portion of the ferrule holding plate 44 is fixed to a drive shaft 45 that hangs down concentrically with the internal gear 42 from above. As shown in FIG. 2, the drive shaft 45 is rotatably supported by the front end of the support arm 46d and fixed in the vertical direction. A boot I74.9-1 is inserted and fixed to the upper end of the drive shaft 45. On the other hand, a motor 50 is arranged and fixed on the rear support plate 46e. A pulley 49-2 is inserted and fixed in the middle of the drive shaft 50a of the motor 50 in correspondence with the pulley 49-1 described in -, and a switch actuating member 51 is inserted and fixed at the upper end of the drive shaft 50a. Pulleys 49-1 and 49-21: Window hole 4.6
The heald 52 is passed through f. Upright board 46b
A pair of left and right limit switches 53 and 5 are located on the rear surface of the upper end.
4 are arranged at predetermined intervals. The limit switches 53 and 54 have push buttons 53a and 54a disposed at their tips, respectively, on the tip end 5 of the switch actuating member 51.
1a rotates and is placed in a position where they come into contact. Incidentally, reference numeral 55 indicates a column installed on the front side of the front support plate 46C, and at the upper end of this column 55, a support member 56 for supporting the optical fiber cord 61 connected to the ferrule 60 is horizontally attached. It is fixed and extends in the direction.

This polishing device 40 is constructed as shown above, and polishes the end face of the ferrule 60 in the following manner. First, the polisher 41 is rotated to zero by the dryer 47 (in this case, in the direction of the arrow).

The ferrule 60 is inserted into the insertion hole 43a of the small diameter gear 43 from above, and the notch 60c formed in the flange 60b of the ferrule 60 is engaged with the mating pin 4.30 fixed to the small diameter float 43. .

This fixes the ferrule 60 to the small diameter gear in the circumferential direction. Next, the ferrule 60 is pressed downward by a pressing member (for example, a temporary spring) disposed on the small diameter gear 43 (not shown), and the end surface 60a (the first
) is pressed against the upper surface 41a of the rotating centering plate 41 with an appropriate striking force (for example, about 50 g). The lower part of the ferrule 60 is held by the holding plate 44 as shown in FIG.
As shown, it is pressed in the direction of arrow F. This results in
The ferrule 60 is tilted by a minute angle of inclination β (FIG. 1(A)) with respect to the vertical line of the upper surface 41a of the polisher 41, and then centered. Next, the ferrule holding plate 4 is moved by the drive shaft 45 in the direction of arrow G and in the opposite direction, arrow 2 Supports nW 46 d and -
・It rotates forward and reverse alternately within a range that does not contact the bolt 52. In synchronization with the forward and reverse rotation of the holding plate 44, the small diameter gear 43 rolls on the inner gear 42 at least in the forward and reverse direction of the arrow J direction (not shown in FIG. 1(a)). It can be rotated 360 degrees. As a result, the ferrule 60 alternately rotates at least 360 degrees in the forward and reverse directions in the direction of the arrow J, and at the same time rotates along the inner circumference of the inner wheel 42 along the arrows G and 11.
It rotates (revolutions) alternately in the forward and reverse directions, and its end surface 60a is polished. The drive shaft 45 includes a pulley 49-1, a heel 152, a pulley 49-2, as shown in FIG.
and is driven by the motor 50 via the drive shaft 50a. The drive shaft 45 is connected to the switch operating section +, I'51
The tip 51a of the actuating part 51 alternately presses the push buttons 53a and 54a of the limit switch 53, 54 due to the rotational movement of the motor 50, thereby alternately switching the motor 50 between forward and reverse rotation. (Fig. 2), it is driven in forward and reverse directions within a predetermined rotation angle range.

The ferrule 6° whose end face has been polished in this way is
As shown in the figure, when the end surface 60a is polished into a convex conical shape and inserted into the sleeve 62 and the end surfaces 60a are abutted against each other, the optical fiber 61a built in along the axis
Since substantially only the end faces of the optical fibers 61a are tightly butted together, no gap occurs in the end faces of the optical fibers 61a, and a good optical connector with extremely low connection loss can be constructed.

Incidentally, the cross-sectional shape of the polished end surface 60a of the ferrule 60 is actually, as an example, when the outer diameter of the ferrule 60 is about 2 mm to 2.5 mm, as shown in FIG. The relief dimension W from the tip of the optical fiber is approximately 10 μm to 20 pm. For this reason, the end face of the optical fiber 61a is polished to a nearly flat shape, so that the two can actually be closely butted together as described above.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and for example, in FIGS.
'Rf +jt7
It is also possible to dispose the external gear so as to mesh with the external gear, and of course it can be applied to other modifications in line with the gist of the present invention.

〔Effect of the invention〕

As explained above-1-, according to the present invention, the end face of the ferrule is pressed against the upper surface of the rotary polishing plate with an appropriate pressing force while the ferrule is tilted by a minute amount with respect to the direction perpendicular to the rotary polishing surface. Since the ferrule can be rotated alternately in the forward and reverse directions within a predetermined rotation angle range, end face polishing can be completed with high precision and stable end face polishing by simply setting the ferrule on the pinion once. This has the remarkable effect of reducing the manufacturing cost by reducing the number of man-hours required for polishing the end face, and also makes it possible to construct a high-performance optical connector with extremely low connection loss.

[Brief explanation of drawings]

FIG. 1(a) is a side view showing the main parts of an embodiment of the ferrule end face polishing device of the present invention, and FIG.
FIG. 2 is a schematic perspective view of the ferrule end face polishing device 40 equipped with the main parts shown in FIG. FIG. 4 is a side view showing the main parts of the first conventional ferrule end polishing device, and FIG. 5 shows the main parts of the second conventional ferrule end polishing device. The side view shown in Figure 6 is a conventional grinding device (No. 4.5).
Fig. 7(A) is a partial perspective view of the ferrule 25-1 whose end face has been polished into a conical convex shape by a conventional polishing device (Fig. 4.5). FIG. 7(b) is a plan view of the ferrule 25-2 polished to ferrule 25-2, FIG. 7(b) is a plan view taken from the direction of arrow C in FIG. A partial side view of a conventional ferrule 11-1 polished into an inclined plane,
FIG. 9 is a side view showing the state in which the ferrule 11-1 of FIG. 8 is inserted into the sleeve 13 and abutted against the other ferrule 11-2. 40... A ferrule end face polishing device which is an embodiment of the present invention, 41...'' - Disc-shaped rotating rlJI polishing plate with a flat surface 41a, 42... Internal gear (large diameter gear) )
, 43... Small diameter float, 43a... Ferrule insertion hole, 44... Ferrule holding plate, 44a... Ferrule insertion hole, 45... Drive shaft of holding plate (44), 60...
... Ferrule, 60a... End face, 61... Optical fiber cord.

Claims (1)

[Claims] 1. In a method for polishing the end face of a ferrule having an optical fiber built in along its axis, a disc-shaped rotary polishing plate having a flat upper surface is rotated, and the ferrule is polished so that the ferrule is polished on the upper surface of the rotary polishing plate. The end face of the ferrule is held in pressure contact with the upper surface of the polishing plate in a state where it is tilted by a minute amount with respect to the vertical direction of the ferrule, and the end face is polished while rotating the ferrule itself alternately in forward and reverse directions within a predetermined rotation angle range. A method for polishing an end face of a ferrule of an optical connector, characterized in that: 2. In a device for polishing the end face of a ferrule that incorporates an optical fiber along its axis, a disc-shaped rotary polishing plate with a flat upper surface is arranged horizontally, and a large-diameter gear is placed above the polishing plate. is arranged and fixed horizontally, a small diameter gear is arranged to mesh with the large diameter gear, a ferrule holding plate is arranged horizontally, and its tip part rotatably supports the small diameter gear, and its base end A ferrule is fixed to a drive shaft that is concentric with the large-diameter gear and hangs down, and a ferrule is inserted into the center of the small-diameter gear from above, and its end surface is pressed against the upper surface of the polishing plate to attach the ferrule circumferentially onto the small-diameter gear. An insertion hole is formed for fixing the ferrule in the same direction, and the ferrule is rotatably inserted into the tip of the ferrule holding plate corresponding to the insertion hole of the small diameter gear, and the ferrule is pressed horizontally to release a minute amount. By forming an insertion hole for tilting the ferrule by 100 degrees, and by swinging the tip side of the ferrule holding plate in the forward and reverse directions by the drive shaft and rolling the small diameter gear in the circumferential direction of the large diameter gear, the ferrule itself An end face polishing device for a ferrule of an optical connector, characterized in that the device is configured to alternately rotate in forward and reverse directions within a predetermined rotation angle range.