JPH0464293B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a synthetic resin pipe having spirally round or polygonal stripes on its inner surface, which is used to protect cables such as electric wires and optical fibers. Related to molding equipment.

(Prior art) Extrusion molding was first used as a means of forming spiral grooves on the inner surface of synthetic resin pipes.
It has been proposed as No. 51-134670 and Utility Model Application No. 59-187418.

(Problems to be Solved by the Invention) The rotary piece in the above-mentioned Utility Model Application No. 51-134670 and the rotor of the Utility Model Application No. 59-187418 cannot be adjusted in mounting position, and have uneven stripes. When changing the depth, it must be replaced with another rotary piece or rotor. Therefore, with conventional equipment, when molding synthetic resin pipes with different depths (or heights) of uneven stripes, it is necessary to prepare multiple rotary pieces or rotors for each depth of the uneven stripes. This is not only extremely inconvenient, but also economically uneconomical.

The present invention has been made in view of the problems of the conventional technology as described above, and its purpose is to form a concavo-convex strip in one part, and to adjust the depth of the concave-convex strip. The objective is to provide a device that can be changed.

(Means for Solving the Problems) In order to achieve the above object, the molding apparatus of the present invention has a molding apparatus that has an outer diameter center of the cylinder in the nipple of an extrusion molding machine that extrudes a single synthetic resin tube or a laminated tube. An eccentric cylinder formed by eccentrically centering the inner hole, an eccentric shaft that fits into the eccentric cylinder so as to be rotatable and fixable, and an axial center of the shaft at the tip of the eccentric shaft. The invention is characterized in that it rotatably supports an eccentric rotating body consisting of a holder holding a shaping roll that is mounted eccentrically by a predetermined amount, and that the shaping roll is located inside the die in front of the nipple. .

(Function) According to the above means, the tube extruded from the extrusion molding machine is pulled in the axial direction by the pulling device,
Inside the tube that moves in the axial direction, the shaping roll bites into the wall thickness to a predetermined depth and rotates eccentrically, so that the grooves (grooves) embossed with the shaping roll continue in a spiral shape. A groove is formed in a spiral shape between the grooves. Since the shaping roll is located within the die of the extrusion molding machine, the outer diameter of the tube is constant, and the uneven stripes are stamped under conditions where deformation is prevented.

Further, by changing the eccentricity of the shaping roll in the eccentric rotating body, it is possible to change the depth of the strip.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

The drawing shows a laminated tube extrusion molding machine equipped with an embossing mechanism that rotates eccentrically inside, and a cylindrical nipple holder 3 is fitted inside a cylindrical main body 1 via a rectifying cylinder 2. A passage 6 through which the melt for forming the inner tube flows is formed between the two parts, and the intermediate die 4 and the nipple 5 connected to the nipple holder 3 are connected to the intermediate die 4 and the nipple 5 connected to the nipple holder 3. A melt supply port 7, which communicates with the passage 6, is formed in the main body 1, which communicates with a tapered nozzle 6' defined by a channel 6, and into which the inner tube a is extruded. .

Further, the intermediate die 4 connected to the main body 1 has a passage 6.
An annular passage 8 is formed in front of the nipple 5, and the passage 8 is inclined toward the central cylindrical part of the nipple 5, and a nozzle 8' between which the outer tube b is extruded and formed is formed between the passage 8 and the outer peripheral surface of the nipple 5. It is formed continuously with the nozzle 6' of the inner tube a, so that a two-layer laminated tube can be extruded. Furthermore, a melt supply port 9 is formed in the intermediate die 4 and communicates with the passage 8 to form the outer tube b.

Inside the nipple holder 3 and nipple 5, an eccentric rotating body 10 having a shaping roll eccentrically mounted at its tip is rotatably supported.

The eccentric rotating body 10 includes an eccentric cylinder 11 having an eccentric hole 11' whose inner hole center is eccentric with respect to the center of the outer diameter of the cylinder, and is rotatable and fixed within the eccentric cylinder 11. Equipped with an eccentric shaft 12 to be fitted, an auxiliary shaft 13 connected to the tip of the eccentric shaft 12 by a screwing means, and a shaping roll 15 attached to the auxiliary shaft 13 so that the amount of eccentricity can be adjusted freely. The shaping roll 15 is located axially forward of the tip of the nipple 5.

The eccentric cylinder 11 in the eccentric rotary body 10 has bearings 16 and 1 arranged at the front and rear inside of the nipple holder 3.
6' for horizontal rotation, and a pulley 17 is fixed via a key 18 to the side end projecting axially rearward from the rear bearing 16.
A retaining nut 19 is screwed onto the end protruding forward from the pulley 1 to hold it in place.
The rotational force is transmitted to 7 by belt transmission.

The eccentric shaft 12 fitted into the eccentric cylinder 11 is a rod rod with a circular cross section and a diameter slightly smaller than the hole diameter of the eccentric hole 11'. It is designed to be able to be engaged and integrated. The engagement between the eccentric shaft 12 and the eccentric cylinder 11 is achieved by cutting a screw hole 20 to a predetermined depth along the axis from the rear end of the eccentric shaft, and inserting a horizontal hole 21 in the middle of the screw hole 20. The stator 22 is made to be freely protrusive and retractable in the radial direction and fitted into the horizontal hole 21, and the screw hole 20 has a length extending forward from the stator 22. When the fixing screw 23 is screwed together, the outer circumferential surface of the distal end of the fixing screw 23 is formed into a tapered surface 24 whose diameter gradually becomes larger toward the rear from the distal end, and the fixing screw 23
The stator 22 moves in and out of the horizontal hole 21 in the radial direction due to the axial movement of the tapered surface 24 due to the forward and backward movement of the stator.
By tightening the fixing screws 23, the stator 22 is pressed against the inner surface of the eccentric cylinder 11, thereby establishing the integration of both.

The tip of the auxiliary shaft 13, which is fixed to the tip of the eccentric shaft 12 with a screw structure, has an insertion groove 2 in a direction perpendicular to the shaft center.
5 is formed with a notch, and the holder 1 is inserted into this insertion groove 25.
The insertion part 26 formed at the base of 4 can be inserted and removed freely, and the setscrew 27 screwed into the insertion part 26
The eccentric position of the holder 14 relative to the eccentric shaft 12 is fixed by inserting the tip of the holder 14 into the bottom of the insertion groove 25.

In the figure, reference numeral 28 denotes an air supply passage that communicates with and opens into the nipple 5, and the cylindrical melt extruded from the nozzles 6' and 8' and laminated and integrated is inflated by compressed air jetted from the tip of the nipple 5. This is to stabilize the shape and dimensions of the molded hose. still,
A heater (not shown) is provided on the outer side of the main body 1 and the intermediate die 4 described above, so that the state of the molten resin can be maintained stably.

Next, to explain the operation of the above-mentioned apparatus, first, molten resin is fed into the melt supply port 7 for forming the inner tube a and the melt supply port 9 for forming the outer tube b, respectively. and 8', the two are laminated to form a laminated tube, and the air supply path 28
The laminated tube is maintained in a cylindrical shape by the compressed air fed in from the extrusion molding machine, and the process before the extrusion molding machine is as is well known today: it is passed through a cooling water tank to cool and harden, and then sequentially pulled out by a pulling machine. It is stretched and wound onto a take-up roll.

Then, the laminated melt tubes at the exit of the extrusion molding machine are pressed against the shaping roll 15 that rotates eccentrically inside the melt tube, so that the shaping roll 1
The concave portion 29 formed by stamping No. 5 is formed in a spiral shape because the molded tube moves in a straight line. Therefore, the pitch of the spirally formed recess 29 can be varied by increasing or decreasing the moving speed of the extruded molding tube.

Additionally, a recess 29 is embossed into the molded tube 30.
The depth of the holder 14 equipped with the shaping roll 15 is
is determined by the amount of eccentricity of the auxiliary shaft 13 fixed to the eccentric shaft 12 with respect to the axis. That is, first, the holder 1 is
4 to the desired amount of eccentricity, and then attach the holder 14.
This is completed by tightening the set screw 27 provided in the holder 14 to integrate the auxiliary shaft 13 and the holder 14. Incidentally, in the above-mentioned operation, if the amount of eccentricity is insufficient or excessive with respect to the set value, fine adjustment is performed by changing the engagement position of the eccentric shaft 12 with respect to the eccentric cylinder 11. In this case, the fixing screw 23 screwed onto the eccentric shaft 12 is loosened to separate the stator 22 from the inner surface of the eccentric cylinder 11, thereby making the eccentric shaft 12 rotatable relative to the eccentric cylinder 11. Under this condition, by rotating the eccentric shaft 12 by 180 degrees (half a rotation) relative to the eccentric tube 11, the amount of eccentricity changes from maximum (see Figure 6) to zero (see Figure 7).
In the middle, the amount of eccentricity is proportional to the rotation angle.

That is, the position where the amount of eccentricity is maximum is the position where the center of the eccentric shaft 12 is farthest from the center of the eccentric cylinder 11, and the position where the center of the eccentric cylinder 11 and the center of the eccentric shaft 12 coincide. In this relationship, the amount of eccentricity is zero.

In addition, in the case of the above laminated tube, by using a hard synthetic resin for the inner tube a and a soft synthetic resin for the outer tube b,
The inner tube a is formed into a spiral shape by a shaping roll 15, and a reinforcing aggregate is integrally attached to the inner side of the flexible tube (hose) in a spiral shape.

Furthermore, in the eccentric rotating body 10 described above, the eccentric shaft 12, the auxiliary shaft 13, and the holder 14 may of course be made into one piece, and in that case, the rotation of the one piece with respect to the eccentric cylinder is adjusted. to adjust the amount of eccentricity.

(Effects of the Invention) Since the molding device of the present invention has the above-described configuration, it can be easily manufactured by modifying an extrusion molding machine normally used for molding hoses, and The depth (or height) of the uneven strips can be adjusted without replacing the shaping roll itself.
This can be easily adjusted by adjusting the amount of eccentricity with respect to the eccentric axis of the holder holding the shaping roll.

Therefore, adjusting the depth (or height) of the uneven stripes is very rational as it prevents the uneconomical effects of preparing and replacing multiple shaping rolls and the increase in the number of parts as in conventional equipment. It is possible to provide a molding device rich in Moreover, since the spirally arranged round or polygonal strips are formed between a shaping roll installed on an eccentric rotating body and a die that regulates the outside of the extruded tube, dimensional accuracy is constant and the outer circumferential surface is can form smooth and stable hoses.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a longitudinal sectional front view, FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, and FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. cross-sectional view,
Figure 4 is an enlarged sectional view of the main part, Figure 5 is 5 of Figure 4.
6 and 7 are explanatory diagrams showing the relative relationship between the eccentric cylinder and the eccentric shaft, and 8
The figure is a partially cutaway front view of the molded hose. In the figure, 1... Main body, 4... Intermediate die, 5... Nipple, 6', 8'... Nozzle, 10... Eccentric rotating body, 11... Eccentric tube, 12... Eccentric shaft, 14...
Holder, 15... Shaping roll, 29... Concavity,
30... Molded hose.

Claims (1)

[Claims] 1 Inside the nipple of an extrusion molding machine that extrudes a single synthetic resin tube or a laminated tube, there is an eccentric tube formed with the center of the inner hole eccentric to the center of the outer diameter of the tube, and an eccentric tube inside the eccentric tube. An eccentric rotating body consisting of an eccentric shaft that is fitted in such a way that it can be freely rotated and fixed, and a holder that holds a shaping roll that is attached to the tip of the eccentric shaft so as to be eccentric by a predetermined amount from the axis of the shaft. A molding device for a synthetic resin pipe having a circular or polygonal strip spirally formed on an inner surface, characterized in that the shaping roll is rotatably supported on a shaft, and the shaping roll is located in a die in front of the nipple.