JPH0612911Y2 - Extrusion molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a nipple used for continuously extruding a power / cable jacket and an extruder for the same.

[Technical background]

Electric wires and cables (hereinafter referred to as "cables") are made by twisting an insulating core wire together with jute or paper interposition, winding a paper or cloth tape over it to form a cable core, and then extruding an outer jacket on the core. Manufactured. The extruder will be described with reference to FIG. 3. The die 3 is attached to the crosshead 1 via the die holder 2 and at the rear of the die.
A nipple 5 is attached via a nipple holder 4, and the cable core a is penetrated onto the central axis of the nipple 5, and the resin mixture b for the jacket is extruded from the crosshead 1 to the outer circumference of the cable core a to cover the jacket. form c.

At the time of this extrusion molding, as described above, jute, paper interposition, paper, and cloth tape are used for the cable core a, and thin scraps are generated from these, and during continuous operation,
These rub against the inner surface of the nipple 5, and these scraps accumulate in the nipple 5 together with the fine scraps, and occasionally this deposit passes through the nipple 5 and enters between the cable core a and the jacket c, and the cable jacket A bump is generated in c. The cable with the bumps is disposed of as a product having a poor appearance and a defective outer diameter, resulting in an economic loss.

In view of the above, it is an object of the present invention to eliminate the accumulation of the scraps and the like in the nipple.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, in the present invention, in the above-described cable extrusion molding nipple, an inner sleeve and an outer sleeve are provided, and the inner sleeve is an outer portion of the electric wire / cable core passing therethrough. A straight pipe part with an inner diameter larger than the diameter and a certain wall thickness, and the taper where the wall thickness gradually decreases from the tip of the straight pipe part to the inner diameter close to the outer diameter of the wire / cable core. The pipe portion and a thin land portion extending from the tip of the tapered pipe portion are integrally formed, and a plurality of through holes are bored in the circumferential direction of the tapered pipe portion. An approach portion which is fitted in the pipe portion and forms a cavity from the outer surface of the tapered sleeve portion of the inner sleeve to the downstream direction of the outer surface of the land portion to be fitted, and a nipple run on the downstream side thereof. Doo is had a structure composed integrally formed.

An external air passage may be formed between the straight pipe portion of the inner sleeve and the approach portion of the outer sleeve from the base end thereof through the cavity.

The tip of the land portion of the inner sleeve may be separated from the inner surface of the outer sleeve, and the periphery of the tip of the land portion of both sleeves may be chamfered or rounded outward.

Between the front part of the inner surface of the approach part of the outer sleeve and the outer surface of the tapered part of the inner sleeve and the land part,
It is preferable to provide a spiral ridge in the axial direction.

Further, each nipple according to the present invention can be adopted in the above-mentioned extrusion molding machine in which the die is attached to the die holder of the crosshead and the nipple is attached via the nipple holder.

[Action]

When the nipple constructed in this way is mounted on an extrusion molding machine and operated in the same manner as in the past, the cable core is supported by both the land parts of the inner sleeve and the outer sleeve and advances along the center axis of the die. Then, the outer cover is extrusion-molded on the outer periphery thereof.

Further, when the air is sucked into the inner sleeve, the paper, thin debris of fibers and fibers and scraps coming out of the cable core are sucked up to reach the land portion of the outer sleeve and removed through the cavity and the through hole. At this time, when the outside air passage is formed, the outside air smoothly flows into the cavity, and when the spiral ridge is formed, the intake air becomes more spiral and the dust removing effect is enhanced.

[Embodiment 1] As shown in FIGS. 1 and 2, the nipple 5 is composed of an inner sleeve 10 and an outer sleeve 11, and the inner sleeve 10 has a constant inner diameter larger than the outer diameter of the cable core a. The straight pipe portion 10a having a thickness and the straight pipe portion 1
0a The taper pipe portion 1 in which the inner diameter is gradually reduced from the tip to the outer diameter of the cable core a, and the wall thickness is gradually reduced.
0b and a thin land portion 10c extending from the tip of the tapered tube portion 10b are integrally formed. Four through holes 12 are formed in the circumferential direction of the tapered tube portion 10b. The number and size of the through holes 12 are appropriately set in consideration of the suction effect described later, and if the axes of all the through holes 12 are inclined in the circumferential direction (arrow direction in FIG. 2), the intake air is swirled. Therefore, the suction effect described later is improved.

The outer sleeve 11 includes a straight pipe portion 10a, a tapered pipe portion 10b, and a land portion 10c of the inner sleeve 10.
Is formed on the inner sleeve 10. A cavity 13 is formed between the approach portion 11a and the tapered tube portion 10b when the inner sleeve 10 is fitted.

A zirconia charcoal layer is formed on the inner surfaces of both lands 10c and 11b of the inner sleeve 10 and the outer sleeve 11 to improve the lubricity with the cable core a, reduce the generation of abrasion dust, and impart wear resistance. is doing. Further, outward chamfers d are formed around the tips of both lands 10c and 11b.

The nipple 5 of the embodiment is configured as described above, and as shown in FIG. 3, the nipple holder 4a for the inner sleeve 10 and the nipple holder 4b for the outer sleeve 11 are provided.
The cross-head 1 and the die holder 2 are attached to form the intake port 14 in the nipple holder 4a, and the cable core a insertion port is closed by the rubber packing 15. An intake pump 17 is connected to the intake port 14 via a regulator V and a solid (dust) separation tank 16. The solid separation tank 16 has water w sealed therein,
The intake air containing dust flows into the water w and the dust is removed. In the figure, s is a screw for adjusting the position of the nipple 5.

Therefore, the cable core a is connected to the nipple 5 as in the conventional case.
When the resin mixture b is injected into the crosshead 1 while being passed on the central axes of the (inner sleeve 10, outer sleeve 11) and the die 3, the cable core a is connected to the land portion 10c of the inner sleeve 10 and the outer sleeve 11. While being supported by the land portion 11b, it passes through the die 3 and an outer cover c is extruded on the outer periphery thereof.

At this time, the debris from the cable core a is sucked up to the land portion 11b of the outer sleeve 11 and removed through the cavity 13 and the through hole 12. The removed debris is collected in the solid separation tank 16. By the intake, the cavity 1
Outside air flows into the nozzle 3 through the gap between the inner sleeve 10, the nipple holder 4a and the outer sleeve 11, and the nipple holder 4b.

[Embodiment 2] As shown in FIG. 4, the nipple of this embodiment has a groove 18 extending from the base end to the cavity 13 on the inner surface of the approach portion 11a as shown in FIG. The front surface of the inner surface of the approach portion is provided with a spiral ridge 20 in the axial direction thereof. Further, as shown in FIG. 5, the extruder having the nipple 5 of this embodiment has a groove 1 communicating with the groove 18 on the inner surface of the nipple holder 4b.
9 is formed. An appropriate number of grooves 18 and 19 are provided at equal intervals around the circumference.

Therefore, when the intake pump 17 inhales, the groove 1
The inside of the inner sleeve 10 is sucked while the outside air flows into the cavity 13 through 8 and 19, and the debris that comes out of the cable core a is removed in the same manner as in the first embodiment.

The grooves 18 and 19 may be provided on the outer surfaces of the inner sleeve 10 and the nipple holder 4a, and the protrusion 20
It may be provided on the outer surfaces of the tapered tube portion 10b and the land portion 10c of the inner sleeve 10.

In addition, also in the said Example 1, the protrusion 20 can be provided.

[Effect of device]

Since the present invention is configured as described above, it is possible to provide an extrusion molding machine in which debris from the cable core does not enter the cable core and the outer cover. At this time, if the outside air passage and the spiral protrusion are provided, the debris can be removed more reliably, and the intrusion into the cable core or the like can be eliminated.

Therefore, according to the present invention, no hump is generated, the appearance of the cable is not bad, the outer diameter is not bad, and the economical loss is also eliminated.

[Brief description of drawings]

1 and 4 are cross-sectional views of the respective embodiments of the extrusion molding nipple according to the present invention, FIG. 2 is a left side view of a main part of FIG. 1, and FIGS. 3 and 5 are the same. It is sectional drawing for each mounting description to the extrusion molding machine of an Example. 1 ... Crosshead, 2 ... Die holder, 3 ... Die, 4, 4a, 4b ... Nipple holder, 5 ... Nipple, 10 ... Inner sleeve, 10a ... Straight pipe part, 10b ... Tapered pipe Part, 10c ... Land part, 11 ... Outer sleeve, 11a ... Approach part, 11b ... Land part, 12 ... Through hole, 13 ... Cavity, 14 ... Intake port, 15 ... Rubber packing, 16 ...... Solid separation tank, 17 ...... intake pump, 18, 19 ...... groove (outside air passage), 20 ...... projection, a ...... cable core, b …… resin admixture, c …… cover.

Claims (5)

[Scope of utility model registration request] 1. A nipple for extruding an electric wire / cable jacket, comprising an inner sleeve and an outer sleeve, the inner sleeve having a constant wall thickness with an inner diameter larger than an outer diameter of the electric wire / cable core passing therethrough. The straight pipe part that has been held, the taper pipe part where the inner diameter gradually decreases from the tip of the straight pipe part until the inner diameter is close to the outer diameter of the electric wire / cable core, and the wall thickness gradually decreases, from the tip of the taper pipe part A thin land portion that extends is integrally formed, and a plurality of through holes are formed in the circumferential direction of the tapered tube portion. The outer sleeve is fitted on the straight tube portion of the inner sleeve, and the inner sleeve is formed. Of the taper pipe part outer surface to the land part outer surface in the downstream direction to form a cavity to be fitted and the approach part, and the land is integrally formed on the downstream side thereof. Extrusion nipple. 2. The extrusion molding nipple according to claim 1, wherein an outside air passage leading from the base end to the cavity is formed between the straight pipe portion of the inner sleeve and the approach portion of the outer sleeve. Nipple for extrusion molding. 3. The extrusion molding nipple according to claim 1, wherein the tip of the land portion of the inner sleeve is separated from the inner surface of the outer sleeve, and the periphery of the tip of the land portion of both sleeves faces outward. A nipple for extrusion molding, which is chamfered or R-cut. 4. The extrusion molding nipple according to claim 1, wherein between the inner surface front part of the approach part of the outer sleeve and the tapered tube part and the outer surface of the land part of the inner sleeve. A nipple for extrusion molding, which is provided with an axial spiral protrusion. 5. A die is attached to a die holder of a crosshead, and a nipple is attached via a nipple holder, a required gap is formed between the die and the nipple, and a resin mixture is passed through the gap to the resin mixture. Injecting, while passing the wire and cable core on the center axis of the die and nipple, in the extrusion molding machine for extrusion coating the resin mixture on the outer periphery, the nipple, claim (1) to (4) An extrusion molding machine characterized in that any one of the above is used as an extrusion molding nipple, and an intake means is connected to the inside of the inner sleeve.