JP4482242B2 - Ferrule cutting device and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ferrule that is a member that holds an optical fiber in an optical connector, and particularly relates to a cutting device and a cutting method for separating a peripheral portion from a cut portion of a ferrule after injection molding.
[0002]
[Prior art]
FIG. 12 (a) shows an injection-molded ferrule molded product 51, which is formed by kneading ceramic powder such as zirconia with an injection molding machine or by injecting plastic such as epoxy resin into a mold. is there. The ferrule 52 as a product is formed by integrally forming, for example, a shaft portion 53 and a flange portion 54 that protrudes in the radial direction from one end portion or a middle portion thereof, and a through hole 55 is formed in the shaft center of the shaft portion 53. Yes. Usually, the ferrule molded product 51 is formed in a state where a plurality of ferrules 52 are taken, that is, a plurality (four in the illustrated example) of ferrules 52 are connected by a runner or the like. As a result, the gate at the boundary between the central sprue 56, the plurality of runners 57 including the branch 57a extending radially from the sprue 56 and the peripheral ring 57b at the tip thereof, and the inner peripheral edge of the peripheral ring 57b and the outer peripheral edge of the flange portion 54 58 is attached to the ferrule 52.
[0003]
After the injection molding, the ferrule molded product 51 is taken out from the injection mold by the take-out machine, applied to the inspection machine and inspected for clogging of the through hole 55, and then applied to the cutting device shown in FIG. Unnecessary parts are excised as shown in FIG. The conventional cutting device is configured to push the cut part of the injection-molded ferrule 52 into the die hole 63 of the die 62 by the punch 61 and separate the peripheral part from the cut part. In the illustrated example, the cut portion is the outer peripheral edge (boundary with the gate 58) of the flange portion 54, and the peripheral portion is a peripheral ring 57b. In addition, it is good also considering the inner periphery (base edge) or radius center part of the flange part 54 as a cut part.
[0004]
[Problems to be solved by the invention]
However, the ferrule 52 formed by injection molding from a kneaded ceramic powder such as zirconia is very brittle. For this reason, there were the following problems (1) and (2).
(1) Due to the impact when the flange portion 54 of the ferrule 52 is pushed into the die hole 63 by the punch 61, as shown in FIG. 12 (b), the peripheral ring 57b and the branch 57a of the runner 57 are cracked, and unnecessary portions are separated. turn into. Unnecessary parts that have been scattered are scattered on the dice 62, and it is necessary to clean them manually, so a continuous cut operation cannot be performed.
(2) The flange portion 54 of the ferrule 52 may be broken by the impact, and the ferrule 52 must of course be discarded as a defective product.
[0005]
According to the analysis of the present inventor, it is considered that the reason why each part breaks due to the impact is due to the following reasons (1) and (2).
(1) For example, the ferrule 52 made of zirconia powder has a tendency to be brittle at room temperature.
(2) When the punch 61 is pushed in, the peripheral ring 57b and the branch 57a of the runner 57 move wildly.
[0006]
Therefore, the present inventor first provides a heating device for the die 62 and the punch 61, heats the flange portion 54 and the peripheral ring 57b to a temperature at which the ductility increases, and applies the punch to the flange portion 54 after the heating. Considering the separation. However, in that case, the following new problems (3) and (4) occurred.
[0007]
{Circle around (3)} The flange portion 54 of the ferrule 52 is excessively heated or the shaft portion 53 that is not required to be heated is softened and may be deformed.
{Circle around (4)} The flange portion 54 and the peripheral ring 57b that have been heated and softened adhere to the abutting die 62 or punch 61 (particularly the side on which the heating device is provided) and remain attached even after the separation.
[0008]
The object of the present invention is to solve the above-mentioned problems, and the peripheral part can be separated from the cut part of the ferrule after injection molding without causing the runner to break apart or the ferrule to crack and become defective. It is an object of the present invention to provide a cutting apparatus and a cutting method in which a ferrule does not deform or adhere to a die or a punch.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the following means (1) and (2) of the cutting device and means (3) of the cutting method were adopted.
[0010]
(1) In a ferrule cutting device that pushes a cut portion of an injection-molded ferrule into a die hole of a die by a punch and separates the peripheral portion from the cut portion, the punch cuts out from the peripheral portion after being cut off before hitting the cut portion. In the meantime , a floating stripper that can be displaced relatively to the punch is provided by substantially contacting the peripheral part from the punch side, and the cut part and the peripheral part are heated in the floating stripper. A ferrule cutting device, characterized in that a heating device is provided .
[0011]
Here, the floating mechanism of the floating stripper is not particularly limited, but a mechanism in which the stripper is connected to the mold on the side where the punch is provided via a spring or the stripper is supported by the hydraulic cylinder so as to be relatively displaceable with respect to the punch. A mechanism etc. can be illustrated.
[0012]
Further, pressurized thermal device, the cut portion and the surrounding portion of the ferrule is heated intensively, it is preferably provided the other portion of the ferrule so as not to minimize heating. The heating device is not particularly limited, and examples thereof include an electric heater and heating oil circulation. The heating temperature varies depending on the ferrule material. For example, when the material is zirconia powder, the heating temperature is 40 to 60 ° C., preferably 45 to 55 ° C.
[0013]
Moreover, it is preferable to provide an air ejection device for blowing off the ferrule chips generated by the separation by air ejection in at least one of a die, a punch or a stripper.
[0015]
The air ejection port of the air ejection device is not particularly limited, but is preferably provided in the die hole of the die or in the front end surface of the punch.
[0016]
( 2 ) In a ferrule cutting method in which a cut portion of an injection-molded ferrule is pushed into a die hole of a die by a punch to separate the peripheral portion from the cut portion, the punch is pulled out from the peripheral portion after being cut off before hitting the cut portion. In the meantime , a floating stripper provided so as to be relatively displaceable with respect to the punch is substantially brought into contact with the peripheral portion from the punch side to suppress the movement of the peripheral portion, and the heating device provided in the floating stripper A ferrule cutting method, wherein the cut portion and the surrounding portion are heated to a temperature at which the ductility increases at the initial stage of contact, and a punch is applied to the cut portion after the heating.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. FIG. 11 (a) shows an injection-molded ferrule molded product 1, which is formed by injecting ceramic powder such as zirconia with an injection molding machine or injecting plastic such as epoxy resin into a mold. is there. The ferrule 2 as a product is formed by, for example, integrally forming a shaft portion 3 and a circular flange portion 4 projecting in the radial direction from one end portion or a middle portion thereof, and a through hole 5 is formed in the shaft center of the shaft portion 3. Has been. Usually, the ferrule molded product 1 is formed in a state where a plurality of ferrules 2 are taken, that is, a plurality (four in the illustrated example) of ferrules 2 are connected by a runner or the like. As a result, the gate at the boundary between the central sprue 6, the plurality of runners 7 including the branch 7a extending radially from the sprue 6 and the peripheral ring 7b at the tip thereof, and the inner peripheral edge of the peripheral ring 7b and the outer peripheral edge of the flange portion 4 8 is attached to the ferrule 2.
[0018]
1 and 2 show a cutting device that pushes a cut portion of an injection-molded ferrule 2 into a die hole of a die by a punch to separate the peripheral portion from the cut portion and cuts an unnecessary portion. In the illustrated example (FIG. 10), the cut portion is the outer peripheral edge (boundary with the gate 8) of the flange portion 4, and the peripheral portion is the peripheral ring 7b. In addition, it is good also considering the inner peripheral edge (root edge) or radius center part of the flange part 4 as a cut part. The cutting apparatus is configured around a lower mold 10 and an upper mold 30 that is driven up and down by a main lifting mechanism (not shown).
[0019]
The lower mold 10 includes a lowermost base 11, a plurality of legs 12 that are erected and fixed to the base 11, a holder 13 that is erected and fixed to the upper part of the legs 12, and 4 that is inserted into a recess of the holder 13. One die 14 and a holding block 15 that presses all the dies 14 into the recesses of the holder 13 and fastens them in a replaceable manner. A die hole 16 having a cross-sectional shape corresponding to the shape of the outer peripheral edge of the flange portion 4 is formed in the die 14. Thus, since the lower mold | type 10 is comprised so that exchange of the dice | dies 14 is possible, it can respond easily to the ferrule 2 from which a cut part differs by dice | dies exchange.
[0020]
An ejector plate 17 that is driven up and down by a sub-lifting mechanism (not shown) is disposed below the holder 13 and between the legs 12, and ejector pins 18 that are erected and fixed to the ejector plate 17 enter the die hole 16. is doing. The ejector plate 17 and the ejector pin 18 are formed with an air flow hole 19 that communicates with an air pump (not shown), and is opened as an air outlet 20 on the upper end surface of the ejector pin 18. The air ejection port 20 opens in the die hole 16 when the ejector pin 18 is lowered, and opens outside the die hole 16 when the ejector pin 18 is raised.
[0021]
The upper mold 30 includes an uppermost base 31, four punches 32 arranged on the lower side of the base 31, and a pressing block 33 that presses all the punches 32 against the base 31 and is fastened in a replaceable manner. An edge having a shape corresponding to the shape of the outer peripheral edge of the flange portion 4 is formed at the lower end of the punch 32. Thus, since the upper mold | type 30 is comprised so that the punch 32 can be replaced | exchanged, it can respond easily to the ferrule 2 from which a cut part differs by punch exchange.
[0022]
An air flow hole 34 communicating with the air pump (not shown) is formed in the base 31 and the punch 32, and opens as an air outlet 35 on the lower end surface (tip surface) of the punch 32. The air circulation hole 34 and the air ejection port 35 together with the air pump, the air circulation hole 19 and the air ejection port 20 constitute an air ejection device for blowing off the ferrule chips generated by the separation by air ejection. ing.
[0023]
The upper die 30 has a punch 32 side until the punch 32 comes out of the peripheral ring 7b as a peripheral portion after being cut off before hitting the outer peripheral edge (boundary with the gate 8) of the flange portion 4 as a cut portion. A stripper plate 36 is provided as a stripper that substantially contacts the peripheral ring 7b and suppresses the movement of the peripheral ring 7b. The stripper plate 36 is a floating stripper provided so as to be relatively displaceable with respect to the punch 32. The floating mechanism is a mechanism in which the stripper plate 36 is connected to the holding block 33 by a plurality of coil springs 37 and suspended. is there. The stripper plate 36 is formed with four insertion holes 38 through which the lower ends of the punches 32 are inserted. Accordingly, the peripheral portion of the insertion hole 38 in the lower surface of the stripper plate 36 is a portion that substantially contacts the peripheral ring 7b.
[0024]
The stripper plate 36 is provided with an electric heater 39 as a heating device for heating the outer peripheral edge of the flange portion 4 as a cut portion and the peripheral ring 7b as a peripheral portion (built-in in the illustrated example). The stripper plate 36 is entirely made of metal, and therefore the heat of the electric heater 39 is conducted to the entire stripper plate 36.
[0025]
The holding block 15 of the lower mold 10 may also be provided with an electric heater 22 as a heating device for heating the outer peripheral edge of the flange portion 4 as a cut portion and the peripheral ring 7b as a peripheral portion (not provided). May be) The entire holding block 15 is made of metal. Therefore, the heat of the electric heater 22 is conducted to the entire holding block 15 and also to the die 14.
[0026]
A cutting method for separating the peripheral portion from the cut portion using the cutting apparatus configured as described above will be described in the order of steps.
[0027]
(1) The injection-molded ferrule molded product 1 is gripped by a take-out machine, taken out from an injection mold, applied to an inspection machine and inspected for clogging of the through-hole 5, and as shown in FIG. It is set on the lower mold 10 of the cutting device in a state where the mold 30 is raised. Specifically, the shaft portion 3 of each ferrule 2 is inserted into the die hole 16, and the lower end portion of the shaft portion 3 is further inserted into the air flow hole 19 to be positioned, and the flange portion 4, the gate 8, and the surrounding ring 7b is placed on the upper surface of the die 14 around the die hole. In addition, the sprue 6 enters the escape hole 21 formed in the holding block 15 and escapes.
At this time, the stripper plate 36 is suspended from the holding block 33 with the coil spring 37 extended by its own weight, and the lower surface of the stripper plate 36 is below the lower edge of the punch 32 to protect the edge. is doing.
In addition, the electric heater 39 of the stripper plate 36 is energized to heat the stripper plate 36.
[0028]
(2) Next, as shown in FIG. 4, the upper die 30 is lowered, and before the punch 32 hits the outer peripheral edge of the flange portion 4 as a cut portion, the lower surface of the stripper plate 36 (the peripheral portion of the insertion hole 38). From the punch 32 side, it is made to substantially contact | abut to the surrounding ring 7b as a surrounding part. The “substantially abutting” is not only when the lower surface of the stripper plate 36 is firmly brought into contact with the surrounding ring 7b, but also when the lower surface of the stripper plate 36 is brought into close proximity with the surrounding ring 7b. Including meaning.
The substantially abutting continues from before the punch 32 hits the outer peripheral edge of the flange portion 4 until the punch 32 comes out of the peripheral ring 7b after the separation, but at the initial stage of the abutting, the stripper heated by the electric heater 39 is used. Heat is conducted from the plate 36 to the outer peripheral edge of the flange portion 4 and the peripheral ring 7b, and the outer peripheral edge of the flange portion 4 and the peripheral ring 7b are heated to a temperature at which the ductility increases. As described above, the heating temperature varies depending on the material of the ferrule 2, and in the embodiment where the material is zirconia powder, it is heated to around 50 ° C. When this heating takes time, the lowering of the upper mold 30 may be temporarily stopped.
Instead of or in addition to the electric heater 39 of the stripper plate 36, the outer peripheral edge of the flange portion 4 and the peripheral ring 7 b may be heated via the die 14 by the electric heater 22 of the holding block 15.
[0029]
(3) Next, as shown in FIG. 5, the upper die 30 is further lowered, and the punch 32 is applied to the outer peripheral edge of the flange portion 4 after the heating. At this time, since the stripper plate 36 is substantially in contact with the peripheral ring 7 b and does not move, the punch 32 moves down together with the pressing block 33 while compressing the coil spring 37. Subsequently, as shown in FIG. 6, the upper die 30 is lowered, and the outer peripheral edge of the flange portion 4 is pushed into the die hole 16 by the punch 32 to separate the peripheral ring 7 b from the outer peripheral edge of the flange portion 4. By this separation, the ferrule 2 falls into the die hole 16 and the flange portion 4 rests on the upper end surface of the ejector pin 18.
[0030]
(1) Although the impact at the time of pushing in is transmitted to the peripheral ring 7b and the branch 7a of the runner 7, the peripheral ring 7b is heated to a temperature at which its ductility is increased, and the stripper plate 36 is substantially omitted from the peripheral ring 7b. Since the contact ring suppresses the movement of the peripheral ring 7b, the peripheral ring 7b and the branch 7a are not broken as shown in FIG. For this reason, the unnecessary portion is held in one piece and can be easily taken out later by the take-out machine, so that it is not necessary to manually clean the broken pieces as in the prior art, and continuous cutting operation is possible.
[0031]
(2) The same impact is also transmitted to the flange portion 4 of the ferrule 2, but the flange portion 4 is not broken by heating the outer peripheral edge of the flange portion 4 to a temperature at which its ductility increases. For this reason, the ferrule 2 does not become a defective product.
[0032]
(3) Since the outer peripheral edge of the flange portion 4 and the peripheral ring 7b are heated from the stripper plate 36 with a small contact area, heat is not easily transmitted to the die 14 and the punch 32, and the flange portion 4 is not excessively heated. The shaft 3 that does not require heating is not heated. For this reason, there is no possibility that the flange portion 4 and the shaft portion 3 are softened and deformed.
[0033]
(4) Next, as shown in FIG. 7, the upper mold | type 30 is raised, the punch 32 is cut off, and it is made to come out from the surrounding ring 7b after cutting.
(4) At this time, the punch 32 is lifted together with the holding block 33 while extending the coil spring 37, and the stripper plate 36 is still in contact with the peripheral ring 7b and is heated to suppress the movement of the peripheral ring 7b. The peripheral ring 7b does not adhere to the punch 32 and move upward.
[0034]
(5) Subsequently, as shown in FIG. 8, the upper die 30 is raised, the stripper plate 36 is separated from the peripheral ring 7b, and the unnecessary part held as one piece as described above is gripped by the unloader. remove. Further, the ejector pin 18 is lifted together with the ejector plate 17, the flange portion 4 of the ferrule 2 is lifted upward from the upper surface of the die 14, and the ferrule 2 is taken out by gripping the flange portion 4 with an unloader.
[0035]
(6) Finally, as shown in FIG. 9, the air outlet 20 at the upper end surface of the ejector pin 18 (in FIG. 9, the ejector pin 18 is lowered and the air outlet 20 is opened in the die hole 16. ) And an air outlet 35 on the lower end surface of the punch 32. The chip 9 of the ferrule 2 generated by the separation may adhere to the edge of the die hole 16 or the edge of the punch 32 or may be scattered on the upper surface of the die 14. Since 9 can be removed by blowing off the air, no manual cleaning is required.
[0036]
Then, the cutting process of said process (1)-(6) can be repeated about the following ferrule molded product 1. FIG. As described above, since manual cleaning of unnecessary portions and manual cleaning of chips are unnecessary, continuous cutting operation is possible.
[0037]
In addition, this invention is not limited to the said embodiment, For example, it can also be suitably changed and embodied as follows, for example in the range which does not deviate from the meaning of invention.
(1) The shape of the flange portion 4 of the ferrule 2 is not limited to a circle, and may be, for example, an oval, an ellipse, a triangle, a quadrangle, or a polygon.
(2) Of the stripper plate 36, only the part around the insertion hole 38 is made of metal and the other part is made of a material having low thermal conductivity, or the part around the insertion hole 38 is made of metal and the other part is made of metal. However, a material with low thermal conductivity is interposed between them to efficiently heat only the portion around the insertion hole 38.
(3) As a stripper, not a stripper plate 36 but a stripper peripheral ring through which the lower end of the punch 32 is inserted.
[0038]
【The invention's effect】
As described above in detail, according to the ferrule cutting device and the cutting method according to the present invention, the runner does not break apart or the ferrule breaks and becomes a defective product. Since the floating stripper is provided with a heating device and the floating stripper is substantially in contact with the periphery of the cut portion, the ferrule may be deformed or attached to the die or punch. There is an excellent effect that there is no.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an entire cutting apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view taken along the line II-II in FIG.
FIG. 3 is a cross-sectional view of a process of setting a ferrule molded product in the cutting method using the same cutting apparatus.
FIG. 4 is a cross-sectional view when the stripper plate substantially contacts the peripheral ring in the cutting method.
FIG. 5 is a cross-sectional view when the punch hits the flange portion in the cutting method.
FIG. 6 is a cross-sectional view when the flange portion is pushed into the die hole in the cutting method.
FIG. 7 is a cross-sectional view when the punch is pulled out from the peripheral ring after being cut in the cutting method.
FIG. 8 is a cross-sectional view when the stripper plate is separated from the peripheral ring in the cutting method.
FIG. 9 is a cross-sectional view when air is ejected from an air ejection port in the cutting method.
10A and 10B show a ferrule molded product to be applied to the cutting apparatus, wherein FIG. 10A is a perspective view before cutting, and FIG. 10B is a perspective view after cutting.
FIG. 11 is a cross-sectional view of a conventional cutting device.
12A and 12B show a ferrule molded product to be applied to the cutting device, in which FIG. 12A is a perspective view before cutting, and FIG. 12B is a perspective view after cutting.
[Explanation of symbols]
1 Ferrule molded product 2 Ferrule 3 shaft
4 Flange 6 Sprue 7 Runner 7a Branch 7b Surrounding ring 8 Gate 9 Chip 10 Lower die 14 Die 16 Die hole 20 Air outlet 22 Electric heater 30 Upper die 32 Punch 35 Air outlet 36 Stripper plate 37 Coil spring 39 Electric heater

Claims (4)

In the cutting device that pushes the cut part of the injection-molded ferrule into the die hole of the die by a punch and separates the peripheral part from the cut part,
A floating stripper that can be relatively displaced with respect to the punch is provided to suppress the movement of the peripheral part by substantially contacting the peripheral part from the punch side from before the punch hits the cut part until it comes out from the peripheral part after separation. ,
A ferrule cutting device , wherein the floating stripper is provided with a heating device for heating the cut portion and the surrounding portion . The die, the at least one punch or floating stripper, and the separation by the resulting ferrules swarf air air ejection apparatus ferrule cutting device according to claim 1, wherein provided for blowing off the ejection of the. The ferrule cutting device according to claim 2 , wherein an air ejection port of the air ejection device is provided in a die hole of the die or in a front end surface of the punch. In the cutting method of pushing the cut part of the injection-molded ferrule into the die hole of the die with a punch and separating the peripheral part from the cut part,
From the time the punch hits the cut part until it comes out of the peripheral part after separation , the floating stripper provided so as to be able to displace relative to the punch is made to substantially contact the peripheral part from the punch side to suppress the movement of the peripheral part. And
A heating device provided in the floating stripper is used to heat the cut portion and the surrounding portion to a temperature at which the ductility increases at the initial stage of the substantial contact, and a punch is applied to the cut portion after the heating. The ferrule cutting method.

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