JP2002267884A - Cutting device and cutting method for ferrule - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cut a peripheral part from the cutting part of a ferrule after injection molding without breaking a runner in pieces or breaking the ferrule and making it defective. SOLUTION: By using the cutting device, the outer peripheral edge of the flange part 4 of the injection molded ferrule 2 is pushed into the dice hole 16 of a dice 14 by a punch 32 and the peripheral ring 7b is cut off from the outer peripheral edge of the flange part 4. The cutting device is provided with a stripper plate 36 for suppressing the movement of the peripheral ring 7b by roughly abutting on the peripheral ring 7b from the side of the punch 32 before the punch 32 abuts on the cutting part until it gets out of the cut-off peripheral ring 7b and the stripper plate 36 is provided with a heating device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ferrule which is a member for holding an optical fiber in an optical connector, and more particularly to a cutting device and a cutting method for separating a peripheral portion from a cut portion of a ferrule after injection molding. is there.

[0002]

2. Description of the Related Art FIG. 12 (a) shows a ferrule molded product 51 which has been injection-molded. A ferrule molded product such as zirconia or a plastic such as epoxy resin is injected into a mold by an injection molding machine. It is molded. The ferrule 52 to be a product is formed, for example, by integrally forming a shaft portion 53 and a flange portion 54 protruding in a 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. I have. Usually, the ferrule molded product 51 is formed in a state in which a plurality of ferrules 52 are taken, that is, a plurality of (four in the illustrated example) ferrules 52 are connected by a runner or the like. As a result, a plurality of runners 57 including a central sprue 56, a branch 57 a extending radially from the sprue 56 and a peripheral ring 57 b at the tip thereof, and a gate at a boundary between an inner peripheral edge of the peripheral ring 57 b and an outer peripheral edge of the flange portion 54. An unnecessary portion consisting of the ferrule 52 is attached to the ferrule 52.

[0003] The ferrule molded product 51 after the injection molding is taken out of the injection mold by the take-out machine, and is checked by an inspection machine for clogging of the through-hole 55, and then is set by a cutting device shown in FIG. Unnecessary portions are cut off as shown in FIG. In a conventional cutting device, a cut portion of an injection-molded ferrule 52 is formed by a punch 61 with a die 6.
It is configured to be pushed into the second die hole 63 to separate the peripheral portion from the cut portion. In the illustrated example, the cut portion is the outer peripheral edge of the flange portion 54 (boundary with the gate 58).
And the peripheral portion is a peripheral ring 57b. Note that the inner peripheral edge (root edge) or the center of the radius of the flange portion 54 may be the cut portion.

[0004]

However, the ferrule 52 injection-molded from kneaded ceramic powder such as zirconia is very fragile. Therefore, there were the following problems. 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.
As shown in (b), the peripheral ring 57b of the runner 57
In addition, the branch 57a is broken, and unnecessary portions are separated. Unnecessary portions that have fallen apart are scattered on the dies 62 and must be manually cleaned, so that continuous cutting operation cannot be performed. The impact may cause the flange portion 54 of the ferrule 52 to be broken, and the ferrule 52 must of course be discarded as a defective product.

[0005] The reason why each part is broken by the impact is as follows.
According to the analysis of the present inventor, the following reasons (1) and (2) are considered. (1) Ferrule 52 made of, for example, zirconia powder
Indicates a tendency of brittleness at room temperature. (2) When the punch 61 is pushed in, the peripheral ring 57b and the branch 57a of the runner 57 move violently.

Therefore, the inventor first provided a heating device on the die 62 and the punch 61, and heated the flange portion 54 and the peripheral ring 57b to a temperature at which the ductility increased.
It has been considered that the punching is performed by applying a punch to the flange portion 54 after the heating. However, in that case, the following new problem has arisen.

[0007] The flange portion 54 of the ferrule 52 is excessively heated, or the shaft portion 53 that does not need to be heated is softened by heating, which may cause deformation. Heated and softened flange 54 and surrounding ring 5
7b adheres to the contacting die 62 or punch 61 (particularly on the side where the heating device is provided), and remains adhered even after the separation.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to cut off a peripheral portion from a cut portion of a ferrule after injection molding without breaking a runner apart or a ferrule cracking to make a defective product. Another object of the present invention is to provide a cutting device and a cutting method in which a ferrule is not deformed or adheres to a die or a punch.

[0009]

In order to solve the above problems, the following means (1) and (2) of a cutting device and means (3) of a cutting method are employed.

(1) In a ferrule cutting device in which a cut portion of an injection-molded ferrule is pushed into a die hole of a die by a punch and a peripheral portion is cut off from the cut portion, a periphery after the punch hits the cut portion before the punch is cut off. A ferrule cutting device characterized in that a stripper is provided which substantially abuts the peripheral portion from the punch side to suppress the movement of the peripheral portion until it comes out of the portion.

Here, it is preferable that the stripper is a floating stripper provided so as to be relatively displaceable with respect to the punch. The floating mechanism is not particularly limited, and examples thereof include a mechanism in which a stripper is connected via a spring to a mold on which the punch is provided, a mechanism in which the stripper is supported by a fluid pressure cylinder so as to be relatively displaceable with respect to the punch, and the like.

Preferably, at least one of the die, punch and stripper is provided with a heating device for heating the cut portion and the surrounding portion. Most preferably, the stripper is provided with the heating device. Further, it is preferable that the heating device be provided so as to intensively heat the cut portion and the peripheral portion of the ferrule and not to heat the other portion of the ferrule as much as possible. The heating device is not particularly limited,
Examples include an electric heater and circulation of heated oil. The heating temperature varies depending on the material of the ferrule. For example, when the material is zirconia powder, the temperature is set to 40 to 60 ° C, preferably 45 to 55 ° C.

It is preferable that at least one of a die, a punch, and a stripper is provided with an air ejection device for blowing off cuttings of the ferrule generated by the separation by ejecting air.

(2) In a ferrule cutting device in which a cut portion of an injection-molded ferrule is pushed into a die hole of a die by a punch to separate a peripheral portion from the cut portion, at least one of the die or the punch is cut by the cut. A ferrule cutting device provided with an air jetting device for blowing off the generated ferrule chips by air jetting.

The air ejection port of the air ejection device is not particularly limited, but is preferably provided in a die hole of a die or in a tip end face of a punch.

(3) In a ferrule cutting method in which a cut portion of an injection-molded ferrule is pressed into a die hole of a die by a punch to separate a peripheral portion from the cut portion, a periphery after the punch hits the cut portion before the punch is cut off. Until the stripper is pulled out, the stripper is substantially in contact with the peripheral portion from the punch side to suppress the movement of the peripheral portion, and the heating device provided on the stripper is used to cut the cut portion and the peripheral portion at the initial stage of the substantially contact. Is heated to a temperature at which its ductility increases, and a punch is applied to the cut portion after the heating.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described with reference to FIG. FIG. 11A shows an injection-molded ferrule molded product 1, which is formed by kneading ceramic powder such as zirconia or injecting plastic such as epoxy resin into a mold by an injection molding machine. is there. The ferrule 2 to be a product has, for example, a shaft portion 3 and a circular flange portion 4 protruding in a radial direction from one end or an intermediate portion thereof, and a through hole 5 is formed in the shaft center of the shaft portion 3. Have been. Usually, the ferrule molded product 1 takes a plurality of ferrules 2, that is, a plurality (four in the illustrated example).
Are formed in a state where the ferrules 2 are connected by a runner or the like. As a result, the center sprue 6, the branch 7a extending radially from the sprue 6, and the peripheral ring 7
b, and an unnecessary portion consisting of a gate 8 at the boundary between the inner peripheral edge of the peripheral ring 7b and the outer peripheral edge of the flange portion 4 accompanies the ferrule 2.

FIGS. 1 and 2 show a cutting device in which a cut portion of an injection-molded ferrule 2 is pushed into a die hole of a die by a punch to cut off a peripheral portion from the cut portion, thereby cutting off an unnecessary portion. I have. Illustrated example (Fig. 1
0), the cut portion is the outer peripheral edge of the flange portion 4 (gate 8).
The boundary is a peripheral ring 7b. The inner peripheral edge (root edge) or the center of the radius of the flange portion 4 may be the cut portion. The cutting device includes a lower mold 10 and
Upper die 3 driven up and down by a main lifting mechanism (not shown)
It is configured around 0.

The lower mold 10 includes a lowermost base 11 and a base 11.
A plurality of legs 12 erected and fixed on the holder 12, a holder 13 erected and fixed above the legs 12, four dies 14 loaded in the recesses of the holder 13, and all the dies 14 Pressing block 1 that can be replaced and pressed down on
5 is included. The die 14 has a die hole 16 having a cross-sectional shape corresponding to the shape of the outer peripheral edge of the flange portion 4. Since the lower die 10 is configured so that the dies 14 can be exchanged, it is possible to easily cope with the ferrules 2 having different cut portions by exchanging the dies.

Below the holder 13 and between the legs 12, an ejector plate 17 driven up and down by a sub-elevating mechanism (not shown) is provided.
The ejector pin 18 erected and fixed on the die 7 has a die hole 16.
Has entered. An air flow hole 19 is formed in the ejector plate 17 and the ejector pin 18 so as to communicate 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 jet 20
When the ejector pin 18 descends, it opens in the die hole 16, and when the ejector pin 18 rises, the die hole 1 opens.
6. Open outside.

The upper die 30 includes an uppermost base 31 and a base 31.
, And a pressing block 33 that presses all the punches 32 against the base 31 and tightly replaces them. A flange 4 is provided at the lower end of the punch 32.
An edge having a shape corresponding to the shape of the outer peripheral edge is formed. As described above, since the upper die 30 is configured so that the punch 32 can be replaced, it is possible to easily cope with the ferrule 2 having a different cut portion by replacing the punch.

The base 31 and the punch 32 are formed with an air flow hole 34 communicating with the air pump (not shown), and open as an air outlet 35 on the lower end surface (tip surface) of the punch 32. Then, the air circulation hole 34 and the air ejection port 3
Numeral 5 together with the air pump, the air flow holes 19 and the air outlets 20 constitute an air ejection device for blowing off the ferrule chips generated by the separation by ejecting air.

On the upper die 30, a punch 32 is provided with an outer peripheral edge of the flange portion 4 as a cut portion (boundary with the gate 8).
And a stripper plate 36 as a stripper that substantially abuts on the peripheral ring 7b from the punch 32 side and suppresses the movement of the peripheral ring 7b from before the punching until it comes out of the peripheral ring 7b as a peripheral part after separation. . This stripper plate 36 is used for the punch 32
The floating mechanism is a mechanism in which a stripper plate 36 is connected to and suspended from a holding block 33 by a plurality of coil springs 37. The stripper plate 36 has four insertion holes 38 through which the lower ends of the punches 32 are inserted. Accordingly, a portion of the lower surface of the stripper plate 36 around the insertion hole 38 is a portion substantially in contact with the peripheral ring 7b.

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, so that the heat of the electric heater 39 is conducted to the entire stripper plate 36.

The holding block 15 of the lower die 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. (May not be provided). The holding block 15 is entirely made of metal, so that the heat of the electric heater 22 is transmitted to the entire holding block 15 and also to the die 14.

A cutting method for separating a peripheral portion from a cut portion by using the cutting device having the above-described configuration will be described in the order of steps.

(1) Injection molded ferrule molded product 1
Is taken out of the injection mold by being gripped by an unloader,
After being inspected for clogging of the through-hole 5 by an inspection machine,
As shown in FIG. 3, the upper die 30 is set on the lower die 10 of the cutting device in a state where it is raised. Specifically, the shaft 3 of each ferrule 2 is inserted into the die hole 16, and the shaft 3
The lower end of the flange 4, the gate 8 and the peripheral ring 7 b are inserted into the air flow holes 19 and positioned.
Is placed on the upper surface of the die 14 around the die hole. The sprue 6 escapes through the escape hole 21 formed in the holding block 15. 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 located below the lower edge of the punch 32 to protect the edge. are doing. The electric heater 39 of the stripper plate 36 is energized to heat the stripper plate 36.

(2) Next, the upper die 30 is lowered as shown in FIG.
Before hitting the outer peripheral edge of, the lower surface of the stripper plate (the area around the insertion hole) is substantially brought into contact with the peripheral ring 7b as a peripheral area from the punch 32 side. “Substantially abutting” means that the lower surface of the stripper plate 36 is
This means that the lower surface of the stripper plate 36 is stopped at an extremely close position where the lower surface of the stripper plate 36 is brought into contact with the peripheral ring 7b. This approximate contact 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 being cut off.
The heat is conducted from the stripper plate 36 heated by 9 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 their ductility increases. As described above, the heating temperature varies depending on the material of the ferrule 2, and in the embodiment in which the material is zirconia powder, the material is heated to around 50 ° C. If this heating takes time, the lowering of the upper mold 30 may be temporarily stopped. The electric heater 3 of the stripper plate 36
Instead of or in addition to 9, 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.

(3) Next, as shown in FIG. 5, the upper die 30 is further lowered, and a 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 7b and does not move,
The punch 32 and the holding block 33 together with the coil spring 3
7 descends while compressing. 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 so that the flange portion 4 is pressed.
The peripheral ring 7b is separated from the outer peripheral edge of. 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.

The impact at the time of pushing is transmitted to the peripheral ring 7b and the branch 7a of the runner 7, and the peripheral ring 7b is heated to a temperature at which its ductility increases, and the stripper plate 36 is connected to the peripheral ring 7b.
10B, the movement of the peripheral ring 7b is suppressed so as to substantially abut the peripheral ring 7b as shown in FIG.
And the branch 7a does not break. For this reason, the unnecessary part is held as it is, and can be easily taken out later by the take-out machine. Therefore, it is not necessary to manually clean the broken part as in the related art, and the continuous cutting operation becomes possible.

The impact is applied to the flange 4 of the ferrule 2.
However, since the outer peripheral edge of the flange portion 4 is heated to a temperature at which its ductility increases, the flange portion 4 does not break. Therefore, the ferrule 2 does not become defective.

Since the outer peripheral edge of the flange portion 4 and the peripheral ring 7 b are heated from the stripper plate 36 with a small contact area, heat is hardly transmitted to the die 14 and the punch 32, and the flange portion 4 is not excessively heated. In addition, the shaft portion 3 that does not need to be heated is not heated. Therefore, there is no possibility that the flange portion 4 and the shaft portion 3 are softened and deformed.

(4) Next, as shown in FIG. 7, the upper die 30 is raised, and the punch 32 is separated from the peripheral ring 7b after being cut off. At this time, only the punch 32 moves up while extending the coil spring 37 together with the pressing block 33, and the stripper plate 36 is still substantially in contact with the peripheral ring 7b, and the movement of the peripheral ring 7b is suppressed. 7b does not adhere to the punch 32 and move upward.

(5) Subsequently, as shown in FIG.
And stripper plate 36 around ring 7
b, the unnecessary portion held as a unit as described above is grasped and removed by the unloader. Further, the ejector pins 18 are raised together with the ejector plate 17, the flange 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 4 with an unloader.

(6) Finally, as shown in FIG. 9, the air ejection port 20 at the upper end surface of the ejector pin 18 (in the same figure, the ejector pin 18 is lowered and the air ejection port 20 is placed in the die hole 1).
6 and open. ) And the air ejection port 35 on the lower end face of the punch 32 to eject air. The cuttings 9 of the ferrule 2 generated by the separation are removed from the die holes 16.
May adhere to the edge of the hole or the vicinity of the edge of the punch 32, or may be scattered on the upper surface of the die 14. However, since these chips 9 can be blown away by the ejection of the air, they can be removed. No manual cleaning is required.

Subsequently, the cutting steps (1) to (6) can be repeated for the next ferrule molded article 1. As described above, since it is not necessary to manually clean unnecessary portions and manual cleaning of chips, continuous cutting operation is possible.

It should be noted that the present invention is not limited to the above-described embodiment, and may be embodied by appropriately changing the scope of the invention as follows, for example, as follows. (1) The shape of the flange portion 4 of the ferrule 2 is not limited to a circle, and may be, for example, an ellipse, an ellipse, a triangle, a quadrangle, a polygon, or the like. (2) Only the portion around the insertion hole 38 of the stripper plate 36 is made of metal and the other portion is made of a material having low thermal conductivity, or the portion around the insertion hole 38 is made of metal and the other portion is also made of metal. To efficiently heat only the surrounding portion of the insertion hole 38 by interposing a material having low thermal conductivity therebetween. (3) As a stripper, a stripper plate 36
Instead, adopt a stripper peripheral ring through which the lower end of the punch 32 is inserted.

[0038]

As described above in detail, according to the ferrule cutting apparatus and the cutting method according to the present invention, the ferrule after injection molding can be used without causing the runner to break apart or the ferrule to break and becoming a defective product. The peripheral portion can be cut off from the cut portion, and if a heating device is provided in the stripper, there is an excellent effect that the ferrule does not deform or adhere to the die or punch.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an entire cutting device according to an embodiment of the present invention.

FIG. 2 is a plan view taken along line II-II of FIG.

FIG. 3 is a sectional view of a step of setting a ferrule molded product in a cutting method using the cutting device.

FIG. 4 is a cross-sectional view when the stripper plate substantially abuts on a peripheral ring in the cutting method.

FIG. 5 is a cross-sectional view when the punch hits a flange portion in the cutting method.

FIG. 6 is a sectional view when the flange portion is pushed into a die hole in the same cutting method.

FIG. 7 is a cross-sectional view when the punch is separated from a peripheral ring after being cut off in the same cutting method.

FIG. 8 is a sectional view when the stripper plate is separated from a peripheral ring in the cutting method.

FIG. 9 is a cross-sectional view when air is jetted from an air jet port in the cutting method.

10A and 10B show a ferrule molded product to be applied to the cutting device, wherein FIG. 10A is a perspective view before cutting, and FIG. 10B is a perspective view after cutting.

FIG. 11 is a sectional view of a conventional cutting device.

12A and 12B show a ferrule molded product applied to the cutting device, wherein FIG. 12A is a perspective view before cutting, and FIG. 12B is a perspective view after cutting.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ferrule molded product 2 Ferrule 3 Flange part 3 Shaft part 6 Sprue 7 Runner 7a Branch 7b Peripheral ring 8 Gate 9 Cutting powder 10 Lower mold 14 Dice 16 Dice hole 20 Air ejection port 22 Electric heater 30 Upper mold 32 Punch 35 Air ejection port 36 Stripper plate 37 Coil spring 39 Electric heater

Claims (7)

[Claims] 1. A cutting device in which a cut portion of an injection-molded ferrule is pressed into a die hole of a die by a punch to separate a peripheral portion from the cut portion, wherein a peripheral portion after the punch is separated from before the punch hits the cut portion. A cutting device for a ferrule, wherein a stripper is provided which substantially abuts a peripheral portion from a punch side to suppress a movement of the peripheral portion until it comes out. 2. The ferrule cutting device according to claim 1, wherein said stripper is a floating stripper provided so as to be relatively displaceable with respect to a punch. 3. The ferrule cutting device according to claim 1, wherein at least one of the die, punch, and stripper is provided with a heating device for heating the cut portion and a peripheral portion. 4. The ferrule according to claim 1, wherein at least one of said die, punch and stripper is provided with an air ejection device for blowing off cuttings of said ferrule generated by said separation by ejecting air. Cutting equipment. 5. A ferrule cutting device in which a cut portion of an injection-molded ferrule is pushed into a die hole of a die by a punch and a peripheral portion thereof is cut off from the cut portion. An apparatus for cutting ferrules, comprising an air jetting device for blowing off generated chips of ferrules by jetting air. 6. The ferrule cutting device according to claim 4, wherein the air ejection port of the air ejection device is provided in a die hole of the die or in a tip end surface of the punch. 7. A cutting method in which a cut portion of an injection-molded ferrule is pushed into a die hole of a die by a punch and a peripheral portion is cut off from the cut portion. Until the stripper comes off, the stripper is substantially abutted against the peripheral portion from the punch side to suppress the movement of the peripheral portion, and the heating device provided on the stripper is used to remove the cut portion and the peripheral portion at the initial stage of the substantial contact. A method for cutting a ferrule, comprising heating to a temperature at which ductility increases, and applying a punch to a cut portion after the heating.