JPH0750232B2 - Extruder for colored slot - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for extruding a grooved slot used for an optical cable, and more particularly to a device for simultaneously extruding a color band for identifying a groove.

[Prior Art] In general, as illustrated in FIG. 5, a slot 10 for carrying an optical fiber covers a tension member 12 with an inner layer 14 made of an adhesive thermoplastic resin to form a core 16, and The structure is such that an outer layer 18 made of a thermoplastic resin is covered and a spiral groove 20 is provided on the outer surface.

Recently, in order to identify the spiral groove 20, it has been proposed to provide a line 22 on the rib 21 between the spiral grooves 20 and apply ink to the line 22 (see Japanese Utility Model Laid-Open No. 62-71607). ).

[Problems to be Solved by the Invention] However, the above-described ink application method has problems such as bleeding and chipping when poor drying.

Therefore, it has been desired to form a color band on the rib 21 by an extrusion method.

[Means for Solving the Problems] As shown in FIGS. 1 to 3, (1) a rotary die 68 having a peak portion 70 and a valley portion 72 on its inner surface is provided, and the rotary die is continuously run while rotating the rotary die. By extrusion coating the resin for the outer layer on the core 16 to
In a slot extrusion apparatus for producing a slot 10 having a spiral 20 groove, (2) fitting a cylindrical bush 76 into a rotary die 68 in a rotatable and sealed manner, (3) bush A circular groove 84 that goes around the upper end surface is provided on the upper end surface of 76, and a resin passage 86 communicating with the groove 84 is provided with a bush 76.
And the resin passage 86 is communicated with the color band extruder. (4) In the rotary die 68, the tip is opened to the valley 72 and the other end is opened to a position facing the groove 84. A nozzle 94 for performing is provided.

[Example] [1] Line configuration for slot production First, the overall line configuration will be briefly described (Figs. 4a to 4c).

The tension member 12 is fed from the feed 30 and the inner layer 14 is covered by the inner layer extruder 32 to form the core 16 (fourth b
Figure).

The outer layer 18 having the spiral groove 20 is coated on the core 16 by an outer layer extruder 34 having a rotary die (see later).

At this time, the head of the outer layer extruder 34 and the head of the color band extruder 36 are connected to each other (see later) to form the slots 10 to which the color bands 24 are continuously attached (Fig. 4c).

The slot 10 is taken up by the take-up machine 38 and taken up by the take-up machine 40.

42 and 44 are water tanks.

[2] Head structure (1) Portion forming outer layer: In FIG. 1, 50 is a cross head of the outer layer extruder 34, and 52 is its main body.

54 is a nipple holder, and 56 is a nipple.

58 is a bush and 60 is an auxiliary die.

Reference numeral 62 denotes a main gear, which is provided outside the auxiliary die 60 and below the bush 58 (see arrow 48 for up and down), and is rotated by a motor (not shown) via an intermediate gear 64.

66 is a gasket.

A rotary die 68 is connected to the main gear 62. On the inside,
It has a mountain portion 70 and a valley portion 72 (Fig. 2).

74 is a thrust retainer.

(2) Portion for attaching the color band 24: 76 is a bush (see Fig. 3).

It is generally cylindrical in shape, with a lower part 78 thicker and an upper part 80
Is a little thin. The upper surface 82 is provided with a groove 84 that goes around the upper surface 82. The upper surface 82 becomes a pool of resin as described later.
Further, a resin passage 86 is formed in the side wall of the bush 76,
It is connected to the color band extruder 36 (Fig. 1).

A groove 69 is provided on the lower surface of the rotary die 68, and an upper portion 80 of the bush 76 is fitted therein. The bush 76 is fitted on the rotary die 68 coaxially, rotatably, and sealed by a gasket 88.

90 is a holder and 92 is a holding plate.

A nozzle 94 is provided in the rotary die 68 in the radial direction (second
See figure). Its tip 96 opens at the valley 72 and the other end
98 is opened at a position facing the groove 84. Therefore, the nozzle 94 is always in communication with the groove 84 even when the rotary die 68 is rotating.

[3] Operation (mainly FIG. 1) (1) The core 16 is pulled through the centers of the nipple holder 54 and the nipple 56.

The resin 18a for the outer layer 18 is extruded from the outer layer extruder 34,
It is coated on the core 16 through the gap between the nipple 56 and the auxiliary die 60.

(2) When the resin 18a coated on the core 16 is extruded through the rotary die 68, the spiral groove 20 is formed by the peak portion 70 on the inner surface of the die.

(3) The color band resin 24a is extruded from the color band extruder 36, passes through the passage 91 in the holder 90 and the resin passage 86 in the bush 76, and collects in the groove 84 of the upper surface 82.

As mentioned above, the groove 84 is in constant communication with the nozzle 94 of the rotating rotary die 68. Therefore, the resin 24a is attached to the nozzle 94
Then, it is extruded into the valley portion 72 of the inner surface and pushed into the surface of the rib 21 of the slot 10 to form the color band 24.

[Regarding Sliding Property and Sealing Property of Rotating Die] As described above, the rotating die method is known as a method for manufacturing the slot with the spiral groove 20. In this system, the sliding property and the sealing property of the rotary die are particularly required.

For example, when slidability is poor, the pitch of the spiral groove becomes unstable.

If the sealing property is poor, the dimensions and shape of the slot will be unstable.

In the case of the present invention, the gasket 18 seals the resin 18a and the gasket 88 seals the color band resin 24a.

Therefore, for the gaskets 66 and 88, a material that also functions as a sliding material, that is, a sealing material having lubricity (friction resistance) is used.

Such materials include Teflon and plastics filled with graphite (eg polyimide, polyester, P
EEK), carbon, carbon filled with metal and plastic, etc. are suitable.

By using such gaskets 66, 88, the pitch of the spiral groove 20 is stable, and the slot 10 having a stable size and shape can be obtained.

[Effects of the Invention] A rotary die having peaks and valleys on the inner surface is provided, and a spiral groove is formed by extruding and coating a resin for an outer layer onto a core that continuously runs while rotating the rotary die. In a slot extrusion apparatus for manufacturing slots, a cylindrical bush is fitted into a rotary die in a rotatable and sealed state; a circular groove that goes around the upper end surface of the bush is formed on the upper end surface of the bush. And a resin passage communicating with the groove is provided in the bush, and the resin passage is communicated with the color band extruder; in the rotary die, the tip is open to the valley and the other end is to the groove. Since the nozzles that open at the opposite positions are provided, the resin passage in the bush ~ the groove on the upper end surface of the bush ~ the nozzle, between the rotating die and the stationary color band extruder even when the rotary die is rotating.
The color band resin passage that is connected to is always formed.

Therefore, the rotation of the rotary die allows extrusion of the slots with spiral grooves while at the same time allowing the ribs between the slot grooves to be colored by extrusion.

[Brief description of drawings]

 1 to 4c relate to an embodiment of the present invention. FIG. 1 is an explanatory view of a crosshead, FIG. 2 is a sectional view of the rotary die 68 taken along line II-II in FIG. 1, and FIG. 3 is a bush. 76 is an explanatory view, FIG. 4a is a schematic explanatory view of the manufacturing line of the slot 10, FIG. 4b is a sectional view of the core 16, and FIG. 4c is a sectional view of the slot 10. FIG. 5 is an explanatory diagram of a conventional technique. 10: Slot, 12: Tension member 14: Inner layer, 16: Core 18: Outer layer, 18a: Resin 20: Helical groove, 21: Rib 22: Striation, 24: Color band 24a: Resin, 30: Delivery 32: Inner layer Extruder, 34: Outer layer extruder 36: Color band extruder, 38: Take-up machine 40: Winding machine, 50: Crosshead 52: Main body, 54: Nipple holder 56: Nipple, 58: Bush 60: Auxiliary die, 62: Main gear 64: Intermediate gear, 66: Gasket 68: Rotating die, 69: Groove 70: Crest part, 72: Valley part 74: Thrust presser, 76: Bushing 78: Lower part, 80: Upper part 82: Top surface, 84: Groove 86: Resin passage, 88: Gasket 90: Holder, 92: Presser plate 94: Nozzle, 96: Tip 98: Other end

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-25713 (JP, A) JP-A-47-22462 (JP, A) Actual development: Sho-63-194309 (JP, U)

Claims (1)

[Claims] 1. A rotary die having a mountain portion and a valley portion on its inner surface is provided, and a spiral groove is formed by extruding and coating a resin for an outer layer onto a core that continuously runs while rotating the rotary die. In a slot extrusion device for manufacturing a slot, a cylindrical bush is fitted in a rotary die in a rotatable and sealed manner; a circular groove that goes around the upper end surface of the bush is provided on the upper end surface of the bush. And a resin passage communicating with the groove is provided inside the bush, and the resin passage is communicated with the color band extruder; inside the rotary die, the tip is open to the valley and the other end is to the groove. An extrusion device for a slot with color bands, which is provided with nozzles that open at opposite positions.