WO2009072750A1

WO2009072750A1 - Resin tube with multiple inner conduits and machine for manufacturing the tube

Info

Publication number: WO2009072750A1
Application number: PCT/KR2008/006598
Authority: WO
Inventors: Jeong-Ja Jeon
Original assignee: Jeong-Ja Jeon
Priority date: 2007-12-07
Filing date: 2008-11-10
Publication date: 2009-06-11
Also published as: KR20090060027A; CN101910700B; CN101910700A; KR100920476B1

Abstract

Disclosed is a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof capable of preventing the coiled inner conduits from being unfolded and twisted owing to a strength of stability thereof. The synthetic resin tube with a plurality of inner conduits comprises: a synthetic resin outer conduit molded by an extruding process; the plurality of synthetic resin inner conduits molded by an extruding process and located at an inside of the synthetic resin outer conduit; and connecting portions for connecting adjacent inner conduits to each other, wherein looped curves or looped squares are formed through the plurality of inner conduits and the connecting portions in section and parts of each outer circumference of the inner conduits are fused on an inner circumference of the outer conduit.

Description

RESIN TUBE WITH MULTIPLE INNER CONDUITS AND MACHINE FOR MANUFACTURING THE TUBE

Technical Field

[1] The present invention relates to a synthetic resin tube laid essentially the ground during public works for electric and communication railroad line equipment, and more particularly to a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof suitable for optical cable equipments for multichannel communication. Background Art

[2] A synthetic resin tube is essentially established during public works such as electric and communication railroad line construction or waterway construction etc. Here, a wrinkle type tube capable of properly expanding and contracting according to the change of ground status or the change of pressure of the conduit is widely used. This wrinkle type tube can be manufactured through a general extruding manner. For example, the raw materials injected through a hopper are extruded through a screw case and a dice, thereby molding the tube. Here, the wrinkle type tube is extruded and molded through a wrinkle molding dice, which is rotated at the outside of the dice at a predetermined speed in proportion to the extruding speed thereof.

[3] Recently, the wrinkle type tube is mainly and widely used in the public works of an optical cable for multiple communication networks.

[4] For example, a plurality of inner conduits is built-in the wrinkle type tube in the form of a double pipe. In other words, the plurality of the inner conduits smaller than the wrinkle type tube in diameter are built-in the wrinkle type tube and the optical cables are inserted into each inner conduits, thereby establishing the railroad line for multiple communication.

[5] However, in the wrinkle type synthetic resin tube having the plurality of the inner conduits, since the wrinkle type tube and the inner conduits are manually assembled and manufactured through separate extruding processes, there are problems in that the productivity and quality thereof can be deteriorated.

[6] In other words, since the molded inner conduits are manually inserted into the molded synthetic resin tube one by one, the inner conduits are closely inserted into the molded synthetic resin tube without an inserting space thereof and the inserting length of the inner conduits becomes longer, thereby involving much labor and spending much time. Accordingly, there is a problem in that the manufacturing cost thereof can be increased. [7] In order to solve these problems, "Device for manufacturing synthetic resin tube with plurality of inner conduits and its synthetic resin tube (Korean patent registration No. 10-0429014) has been filed and registered by the present applicant. In this patent, the inner and outer conduits are molded through successive extruding processes of first and second extruding machines.

[8] That is, the device for manufacturing synthetic resin tube includes the first extruding machine for forming the inner conduits and the second extruding machine for forming the outer conduit. Here, the second extruding machine serves to receive the inner conduits passing through the first extruding machine and automatically molding the inner conduits located inside the outer conduit.

[9] In this patent technique, since the inner conduits are not manually formed at the inside of the outer conduit, there is an effect in that the works can be very effectively performed in comparison with the conventional art.

[10] However, in the conventional patent technique, since the inner conduits formed at the inside of the outer conduit are individually located respectively, the inner conduits cannot be fixed inside the outer conduit during manufacturing thereof.

[11] Especially, the inner conduits formed at the inside of the outer conduit can be twisted in the course of the arrangement construction of the tube in railroad line. Thus, it can bring about the cutting of the optical cable located at the inside of the inner conduit.

[12] Also, in case of the damage of the conduits owing to natural or artificial accidents, since the location of the inner conduit or the optical cable located inside the inner conduits is changed or the inner conduit or the optical cable are twisted, it has a difficulty in finding out the exact location of corresponding optical cable.

[13] In order to partially solve these problems, Korean patent registration No. 10-0355751 discloses "Multi channel duct assembling body for cable" capable of connecting the inner ducts to each other by using connecting bands and fusing the inner ducts to the outer duct.

[14] Also, Korean patent registration No. 10-0387196 discloses "Manufacturing method of multi channel duct assembling body and method thereof capable of extruding and fusing the outer duct to the outer circumference surface of the inner duct.

[15] However, in the above patent techniques, the entire inner duct are not connected to each other as disclosed in Korean utility model laying-open gazette No. 1999-008221.

[16] That is, the inner ducts are connected to each other through the connecting band.

However, since the connected inner ducts are unfolded in the straight direction thereof before coiling thereof, the inner ducts are coiled correspondingly with the shape of the outer duct and then, they are inserted into the manufactured outer duct.

[17] Here, since the coiled inner ducts has an elastic strength of stability for unfolding them in the straight direction thereof, the inner ducts can be deviated to outside in case that the outer duct is damaged after the construction thereof

[18] Also, in order to put the coiled inner ducts into the insertion passage of the inner duct during manufacturing thereof, there is a problem in that it is necessary to bind the coiled inner ducts to each other through a strings etc.

[19] In order to fasten the fixed inner ducts, Korean patent registration No. 10-0387196 discloses a technique in that a groove is formed at the insertion passage of the inner duct and one side of the outer circumference surface of the coiled inner ducts is inserted into the groove.

[20] However, since the inner ducts made of a flexible material such as a polyethylene are not connected to each other, the inner ducts can be deviated from the groove. Also, there is an inconvenience in that the sectional shape of the insertion passage of the inner duct should be changed according to the number of inner ducts inserted into the inside of the outer duct.

[21] Accordingly, as described above, since the conventional inner ducts are not connected to each other, there are many problems in that the inner ducts can be deviated owing to the elastic strength of stability, a separate fixing work for preventing the inner ducts from being deviated is required, and the construction elements for molding and fusing the inner and other ducts are very complicated.

[22] In order to solve these problems, each inner duct can be integrally formed without the connecting bands. However, there are also problems in that the inner ducts can be torn owing to the load thereof and the space of the vacuous absorption can be lacked.

Disclosure of Invention

Technical Problem

[23] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof in that the plurality of inner conduits is connected to each other through connecting portions, whereby it can prevent the coiled inner conduits from being unfolded owing to a strength of stability thereof and the entire portion or a part of a circumference surface of each inner conduit is fused to an inner circumference surface of the outer conduit, whereby it can prevent the inner conduits from being twisted inside the outer conduit.

[24] Another object of the present invention is to provide a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof in that each inner conduit is connected to the adjacent inner conduit through the connecting portions, whereby it can prevent the optical cable from being cut and find out the exact location of corresponding optical cable during maintenance works owing to an accident thereof. [25] Further another object of the present invention is to provide a synthetic resin rube with a plurality of inner conduits and a manufacturing device thereof capable of preventing the inner conduits from being deviated to outside in case that the outer conduit is damaged after the construction thereof.

[26] Further another object of the present invention is to provide a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof in that the inner and outer conduits can be molded through a series of extruding processes during manufacturing thereof and separate coiling or fixing works of the inner conduits can be eliminated, whereby easily manufacturing a multiple pipe type tube.

[27] Further another object of the present invention is to provide a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof in that a sectional shape of an insertion passage of a dice for molding an external appearance is not restricted to the shape of each inner conduit.

[28] Further another object of the present invention is to provide a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof in that the inner and outer conduits can be molded through a series of extruding processes, whereby increasing the productivity thereof and decreasing the manufacturing cost thereof. Technical Solution

[29] To accomplish the objects, the present invention provides a synthetic resin tube with a plurality of inner conduits comprising: a synthetic resin outer conduit molded by an extruding process; the plurality of synthetic resin inner conduits molded by an extruding process and located at an inside of the synthetic resin outer conduit; and connecting portions for connecting adjacent inner conduits to each other, wherein looped curves or looped squares are formed through the plurality of inner conduits and the connecting portions in section and parts of each outer circumference of the inner conduits are fused on an inner circumference of the outer conduit.

[30] To accomplish the objects, the present invention provides a device for manufacturing a synthetic resin tube with a plurality of inner conduits having hoppers for injecting raw materials therethrough and dices for extruding the injected raw materials comprising: a first extruding machine comprising a first dice for extruding the plurality of the inner conduits formed at a head of a screw case and having a plurality of inner blocks, a plurality of outer blocks separated from each inner block at a predetermined distance, and inner conduit connecting portions for connecting each outer block to each other, raw materials being injected into the gaps between the inner and outer blocks and the inner conduit connecting portions so as to form the plurality of the inner conduits having looped curves or looped squares; a first cooler for cooling the inner conduits, which are extruded and molded through the first dices of the first extruding machine, by means of water-cooling manner formed continuously at a rear portion of the first extruding machine; a second extruding machine continuously arranged in a rear of the first cooler and comprising a receiving pipe for receiving the inner conduits extruded through the first extruding machine and a second dice for molding an outer conduit of surrounding the inner conduits passing through the first extruding machine located at an end portion of the receiving pipe and having a plurality of inner blocks and outer blocks separated from each inner block at a predetermined distance, an admission part of the inner block being gradually narrowed inward and a discharging part of the inner block being gradually widened outward in diameter; and a second cooler for cooling the outer conduit by means of water-cooling manner continuously formed at a rear portion of the second extruding machine and having a set pattern dice for forming wrinkles at a circumference wall of the outer conduit extruded through the second dice.

Advantageous Effects

[31] In the synthetic resin tube with the plurality of inner conduits and the manufacturing device thereof, there are effects in that the plurality of inner conduits is connected to each other through connecting portions, so that it can prevent the coiled inner conduits from being unfolded owing to a strength of stability thereof and the entire portion or a part of a circumference surface of each inner conduit is fused to an inner circumference surface of the outer conduit, so that it can prevent the inner conduits from being twisted inside the outer conduit.

[32] Also, there is another effect in that each inner conduit is connected to the adjacent inner conduit through the connecting portions, so that it can prevent the optical cable from being cut and find out the exact location of corresponding optical cable during maintenance works owing to an accident thereof.

[33] Moreover, there is further another effect in that it can prevent the inner conduits from being deviated to outside in case that the outer conduit is damaged after the construction thereof.

[34] Furthermore, there is further another effect in that the inner and outer conduits can be molded through a series of extruding processes during manufacturing thereof and separate coiling or fixing works of the inner conduits can be eliminated, thereby easily manufacturing a multiple pipe type tube.

[35] There is further another effect in that a sectional shape of an insertion passage of a dice for molding an external appearance is not restricted to the shape of each inner conduit.

[36] There is further another effect in that the inner and outer conduits can be molded through a series of extruding processes, whereby increasing the productivity and decreasing the manufacturing cost thereof. Brief Description of Drawings

[37] The above as well as the other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[38] FIG. 1 is a sectional view illustrating a conventional synthetic resin tube;

[39] FIG. 2 is a sectional view illustrating an inner conduit of a conventional synthetic resin tube;

[40] FIG. 3 is a sectional view illustrating another example of a conventional synthetic resin tube;

[41] FIG. 4 is a sectional view illustrating one side of a synthetic resin tube with a plurality of inner conduits according to the present invention;

[42] FIG. 5 is a sectional view illustrating the other side of a synthetic resin tube with a plurality of inner conduits according to the present invention;

[43] FIG. 6 is a partially perspective view illustrating a synthetic resin tube with a plurality of inner conduits according to the present invention;

[44] FIG. 7 is a front sectional view illustrating an entire construction of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention;

[45] FIG. 8 is a partial side sectional view illustrating a first extruding machine and cooler of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention;

[46] FIG. 9 is a partially enlarged sectional view illustrating an inner structure of a head of the first extruding machine and a first dice of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention;

[47] FIG. 10 is a front sectional view illustrating an arrange structure of a first dice of the device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention;

[48] FIG. 11 is an enlarge sectional view of "A" portion of FIG. 9;

[49] FIG. 12 is a sectional view illustrating first set pattern dices of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention;

[50] FIG. 13 is a side sectional view illustrating an arrange structure of a second extruding machine and second dices of a device for manufacturing the synthetic resin tube with a plurality of inner conduits according to the present invention; and

[51] FIG. 14 is a partially enlarged sectional view illustrating an inner structure of a second extruding machine and second dices of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention. Best Mode for Carrying out the Invention

[52] A preferred embodiment of the invention will be described in detail below with reference to the accompanying drawings.

[53] FIG. 3 is a sectional view illustrating another example of a conventional synthetic resin tube, FIG. 4 is a sectional view illustrating one side of a synthetic resin tube with a plurality of inner conduits according to the present invention, FIG. 5 is a sectional view illustrating the other side of a synthetic resin tube with a plurality of inner conduits according to the present invention, and FIG. 6 is a partially perspective view illustrating a synthetic resin tube with a plurality of inner conduits according to the present invention.

[54] As shown in FIG. 3 through FIG. 6, a synthetic resin tube with a plurality of inner conduits according to the present invention includes a plurality of inner conduits 10, one outer conduit 20 for surrounding the inner conduits 10, and connecting portions 30 for connecting the plurality of inner conduits 10 to each other. Here, looped curves or looped squares are formed through the plurality of inner conduits 10 and the connecting portions 30 in section.

[55] More concretely, the synthetic resin tube with the plurality of inner conduits includes the synthetic resin outer conduit 20 molded by an extruding process, the plurality of synthetic resin inner conduits 10 molded by an extruding process and located at an inside of the synthetic resin outer conduit 20, and the connecting portions 30 for connecting the adjacent inner conduits 10 to each other. Here, the looped curves or the looped squares are formed through the plurality of inner conduits 10 and the connecting portions 30 in section and parts of each outer circumference of the inner conduits 10 are fused on an inner circumference of the outer conduit 20.

[56] FIG. 1 is a sectional view illustrating a conventional synthetic resin tube, FIG. 2 is a sectional view illustrating an inner conduit of a conventional synthetic resin tube, and FIG. 3 is a sectional view illustrating another example of a conventional synthetic resin tube.

[57] The synthetic resin tube with a plurality of inner conduits according to the present invention is different from the conventional art as shown in FIG. 1 through FIG. 3 in terms of the construction thereof.

[58] That is, the plurality of inner conduits 1 is connected through connecting belts 3 as shown in FIG. 2 and then, the coiled inner conduits 1 are injected into the inside of the dice for forming the outer conduit 2, thereby forming the conventional synthetic resin tube as shown in FIG. 1.

[59] Accordingly, in the conventional synthetic resin tube, the opened curves or opened squares are formed in section differently with the synthetic resin tube of the present invention having the looped curve or looped square.

[60] In the conventional synthetic resin tube having the opened curve or the opened square, since the coiled inner conduits 1 are bound to each other and then, the fixed inner conduits 1 are injected into the inside of the dice for forming the outer conduit 2, it is necessary to carry out the coiling and fixing works together.

[61] Also, in order to locate each inner conduit at the assigned positions, a plurality of grooves must be formed at the inner space of the dice. In this case, there are problems in that it cannot take the activeness according to the change of the number of the inner conduit and the dice should be changed according to the shape of the external appearance thereof.

[62] Also, in the conventional synthetic resin tube having the opened curve or the opened square, since the plurality of the inner conduits has any strength of stability for unfolding them in the straight direction thereof, the inner conduits 1 can be twisted and protruded toward the outside of the outer conduit, in case that the welding points between the inner and outer conduits are damaged or the outer conduit is damaged, it can bring about the cutting or the breakdown of the optical cable located at the inside of the inner conduit.

[63] The present invention has been made to solve the above-mentioned problems occurring in the prior art and can be applied to a consecutive manufacturing process of the inner and outer conduits 10 and 20.

[64] That is, the looped curves or the looped squares are formed through the plurality of inner conduits 10 and the connecting portions 30 in section, so that the strength of stability cannot be generated from the inner conduits 10, thereby the inner conduits 10 cannot be twisted in the inside of the outer conduit 20.

[65] Also, it is not restricted to the inner shape of the dice for forming the outer conduit

20 during the manufacturing of the tube.

[66] A device for manufacturing the synthetic resin tube with a plurality of inner conduits according to the present invention will be described below.

[67] Here, the device for manufacturing the synthetic resin tube according to the present invention is an improved invention in comparison with Korean patent registration No. 10-0429014 (Title: device for manufacturing synthetic resin tube with plurality of inner conduits and its synthetic resin tube) filed by the present applicant.

[68] FIG. 7 is a front sectional view illustrating an entire construction of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention.

[69] As shown in FIG. 7, the device for manufacturing the synthetic resin tube with the plurality of inner conduits according to the present invention includes a first extruding machine 100, a first cooler 200, a second extruding machine 300, a second cooler 400, and a traction means 500.

[70] That is, the present invention is characterized in that it includes the first extruding machine 100 for arranging the plurality of inner conduits 10 located at the inside of the outer conduit 20 of a predetermined size at a predetermined interval through the connecting portions 30 by means of an extrusion molding process and forming the looped curves or the looped squares through the plurality of inner conduits 10 and the connecting portions 30 in section and the second extruding machine 200 for extruding the outer conduit 20 of a wrinkled type. Here, the first and second extruding machines 100 and 200 are arranged in order, so that the synthetic resin tube with the plurality of inner conduits can be simultaneously manufactured through the successive extruding process.

[71] FIG. 8 is a partial side sectional view illustrating a first extruding machine and a cooler of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention.

[72] As shown in FIG. 8, the first extruding machine 100 serves to extrude the raw material injected through a hopper 120 by means of a head 160 of a screw case 140 for molding the objective inner conduits 10.

[73] FIG. 9 is a partially enlarged sectional view illustrating an inner structure of a head of a first extruding machine and a first dice of the device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention and FIG. 10 is a front sectional view illustrating an arrange structure of a first dice of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention.

[74] As shown in FIG. 9 and FIG. 10, one first dice 180 for extruding and molding the inner conduits 10 is arranged at a block 170, which is formed at one end portion of the head 160, thereby simultaneously extruding and molding the plurality of the inner conduits 10.

[75] Here, the inside diameter (width Ll) of the first dice 180 is more or less smaller than or the same as that (L2) of the outer conduit 20, which is extruded and molded through the second extruding machine 300.

[76] According to the device for manufacturing the synthetic resin tube with a plurality of inner conduits of present invention, since the dice has built-in a thickness adjusting apparatus, the thickness of the inner conduit 10 can be simply adjusted without change of location of the dice.

[77] More concretely, the first dice 180 for extruding and molding the inner conduits 10 is adjacently arranged at a piece or two pieces of the block 170, which is formed at one end portion of the head 160 of the screw case 140 along the circumference of a pre- determined width Ll, as shown in FIG. 10.

[78] Here, the first dice 180 is attached and deattached to the block 170 by means of a screw. Also, the first dice 180 having an inner block 181 and an outer block 182. Accordingly, the raw materials are extruded in the gap between the inner and outer blocks 181 and 182, thereby extruding and molding the desiring inner conduits 10.

[79] In this time, inner conduit connecting portions 183 are formed at one side and other side of each outer block, so that the raw materials are injected into the inner conduit connecting portions 183.

[80] That is, the raw materials are injected into the gap between the inner and outer blocks

181 and 182 and the inside of an inner conduit connecting portions 183, thereby forming the plurality of inner conduits 10 having the looped curves or looped squares.

[81] Here, a thickness adjusting means 150 can be formed at a proper location between the inner and outer blocks 181 and 182 so as to adjust the thickness of the inner conduit 10, that is, adjust the bias of thickness thereof and maintain the balance thereof.

[82] As shown in FIG. 11, the thickness adjusting means 150 includes a moving part 151 of a ring shape freely and movably formed at a space between the inner and outer blocks 181 and 182 and an adjusting bolt 152 for moving the moving part in all directions screw-coupled to the outer block 182 from at least three directions and protruded toward the inside and outside of the outer block 182.

[83] Here, the outer diameter of the inner conduit 10 is determined by means of the inner diameter of the moving part 151 of a ring shape.

[84] Also, the block 170 includes a flux adjusting member 110 of a bolt shape for adjusting the supplying amount of the raw materials. Moreover, each first dice 180 includes an air supply route 130 for maintaining the internal pressure of the inner conduit 10 during molding thereof.

[85] Continuously, the first cooler 200 is formed at the rear portion of the first extruding machine 100.

[86] The first cooler 200 serves to cure the inner conduits 10, which is extruded and molded through the first dices 180 of the first extruding machine 100, by means of water-cooling manner. The first cooler 200 includes a rectangular water tank 220 of a predetermined length having an opened surface, first set pattern dices 240 for receiving and standardizing each inner conduit 10 extruded and molded through the first dices 180 penetrated from a front end portion of the water tank 220 to an inside of the water tank 220 and corresponding to each first dice 180 of the first extruding machine 100, and an injecting nozzle 270 for sprinkling a cooling water by using a heat exchanger 260 having a refrigerant formed at an outer wall of the water tank 220.

[87] Here, the first cooler 200 serves to circulate the cooling water of the water tank 220 by mean of a circulating pump etc. and cure the inner conduits 10 of high temperature extruded through the first dices 180 by means of the water-cooling manner.

[88] FIG. 12 is a sectional view illustrating first set pattern dices of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention.

[89] As shown in Fig. 12, the first set pattern dice 240 is screw-coupled to a assembling block 241 coupled to the outer circumference wall of the front end portion of the water tank 240. The first set pattern dice 240 includes a molding route 242 for standardizing the size of the outer diameter of each inner conduit 10 and an absorption route 263 for absorbing the outer circumference of each inner conduit 10 through a vacuum pump.

[90] In the meantime, the second extruding machine 300 is continuously arranged in the rear of the first cooler 200 in a line.

[91] The second extruding machine 300 serves to receive the inner conduits 10 extruded and molded through the first extruding machine 100 and extrude and mold the outer conduit 20 at the circumference of the inner conduits 10 at one time.

[92] Also, the second extruding machine 300 serves to extrude the raw material injected through a hopper 320 by means of a head 360 of a screw case 340 for molding the objective outer conduits 20.

[93] FIG. 13 is a side sectional view illustrating an arrange structure of a second extruding machine and second dices of a device for manufacturing the synthetic resin tube with a plurality of inner conduits according to the present invention and FIG. 14 is a partially enlarged sectional view illustrating an inner structure of a second extruding machine and second dices of a device for manufacturing a synthetic resin tube with a plurality of inner conduits according to the present invention.

[94] As shown in FIG. 13 and FIG. 14, the outer conduit 20 is extruded and molded through the second dice 380, which is screw-coupled to the head 360.

[95] Here, the second dice 380 includes an inner block 381 having a flowing route 310 for receiving and passing the plurality of the first inner conduits 10 extruded and molded through the first extruding machine 100 as it is, without change of the location thereof, an outer block 382 separated from the inner block 381 at a predetermined distance, and a gap for extruding and molding the outer conduit 20 located between the inner and outer blocks 381 and 382.

[96] In order to join the outer conduit 20 to the inner conduits 10, as shown in FIG. 14, the admission part of the inner block 381 adjacent to the flowing route 310 is gradually narrowed inward and the discharging part of the inner block 381 adjacent to the flowing route 310 is gradually widened outward in diameter.

[97] That is, since the inner conduits 10 extruded and molded through the first extruding machine 100 are contracted through the first cooler 200, the diameter of the inlet of the flowing route 310 becomes smaller gradually inward. Meanwhile, since the inner conduits 10 passed through the flowing route 310 are heated and expanded through the inner block 381 of high temperature, the diameter of the outlet of the inner block 381 becomes larger gradually outward so as to maintain the expansibility of the inner conduits 10 passed through the inner block 381 of high temperature.

[98] Accordingly, as shown in FIG. 14, the inner conduits 10 are partially fused to the inner circumference surface of the outer conduit 20 while being expanded.

[99] Here, the inside diameter of the outer conduit 20 is more or less larger than or the same as the width of the circumference of the coiled inner conduits 10. However, it is preferred that the inside diameter of the outer conduit 20 is the same as the width of the circumference of the coiled inner conduits so as to easily fuse the inner and outer conduits 10 and 20 to each other.

[100] Also, an adjusting bolt 390 for moving the moving part in all directions screw- coupled to the outer block 382 from three directions can adjust the thickness of the outer conduit 20.

[101] Moreover, a guider 600 for guiding and aligning the inner conduits 10 discharged through the first cooler 200 in order is formed between the first cooler 200 and the second extruding machine 300. Here, the guider 600 includes a cold wind nozzle 620 for cooling the inner conduits 10 by using a cold wind through a separate heat exchanging means.

[102] Also, the second cooler 400 is continuously formed at the rear portion of the second dice 380. The second cooler 400 serves to mold the second conduit 20 extruded and molded through the second dice 380 of the second extruding machine 300 in the form of a wrinkled type and cure the outer conduit 20 by means of water-cooling manner. Moreover, the second cooler 400 includes a rectangular water tank 420 of a predetermined length having an opened surface, a second set pattern dice 440 for receiving the outer conduit 20 extruded and molded through the second dice 280, forming the wrinkles at the circumference wall of the outer conduit 20, and standardizing it penetrated from a front end portion of the water tank 420 to an inside of the water tank 420 and corresponding to the second dice 280 of the second extruding machine 300.

[103] Also, the second set pattern dice 440 serves to receive the power through a power transmission member 430 by means of a separate driving motor and form the wrinkles at the circumference wall of the outer conduit 20 through a rotation of proper speed.

[104] Here, the plurality of the inner conduits 10 is transported together with the outer conduit 20 to be molded.

[105] Also, the second cooler 400 includes an injecting nozzle 450 for sprinkling a cooling water of the water tank 420 by using a circulating pump etc. Accordingly, the second cooler 400 serves to cure the outer conduit 20 of high temperature extruded through the second set pattern dice 440 by means of the water-cooling manner. [106] Here, the second set pattern dice 440 includes an absorption pipe 480 for making the inside of the second set pattern dice 440 vacuous so as to maintain the molding status of the outer conduit 20 passing through the second dice 380. [107] In the meantime, the traction means 500 of a roll type is continuously arranged in the rear of the second cooler 400. [108] The traction means 500 serves to draw out the completed inner and outer conduits 10 and 20 by using a pair of rotating rolls, which is rotated at a proper speed through a separate driving motor. [109] In the meantime, after the molding of the outer conduit 20 through the second dice

380, the inner and outer conduits 10 and 20 touch partially with each other in the course of the cooling and traction processes to be partially fused to each other. [110] Accordingly, since the fusion of the inner and outer conduits 10 and 20 can be naturally performed at the contacting portions thereof through the cooling process of the outer conduit 20, separate equipments for fusing are not required. [I l l] Here, since the fusion of the inner and outer conduits 10 and 20 is generated at only contacting portions thereof, the fixing force between them cannot be strong. [112] However, the reason the inner and outer conduits 10 and 20 are fixed to each other is because it can prevent the inner conduits 10 from being twisted inside the outer conduit

20 during the manufacturing of the tube. [113] That is, it is not necessary for the inner and outer conduits 10 and 20 to be strongly fixed against a very strong shock etc. [114] Accordingly, the inner and outer conduits 10 and 20 are naturally fused to each other through the cooling process of the outer conduit 20 after simple molding of the outer conduit 20, so that separate equipments for fusing are not required in the present invention. [115] In the meantime, the inner and outer conduits 10 and 20 passing through the traction means 500 are stored through a separate winding means of a roll type. [116] A manufacturing process of the synthetic resin tube using the device for manufacturing the synthetic resin tube according to the present invention will be described below. [117] Firstly, the plurality of inner conduits 10 having the looped curves or looped squares arranged at a predetermined distance is extruded and molded through the first dice 180 of the first extruding machine 100. [118] Continuously, the extruded and molded inner conduits 10 are passed through the second dice 380 of the second extruding machine 300 and the outer conduit 20 is extruded and molded at the outer circumferences of each inner conduit 10. [119] Finally, the inner and outer conduits 10 and 20 are naturally fused to each other through the cooling process of the outer conduit 20, thereby simultaneously completing the synthetic resin tube through the successive extruding process.

[120] While this invention has been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments and the drawings, but, on the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims. Industrial Applicability

[121] The present invention relates to a synthetic resin tube laid essentially during public works for electric and communication railroad line equipment, and more particularly to a synthetic resin tube with a plurality of inner conduits and a manufacturing device thereof suitable for optical cable equipments for multichannel communication.

Claims

[1] A synthetic resin tube with a plurality of inner conduits comprising: a synthetic resin outer conduit molded by an extruding process; the plurality of synthetic resin inner conduits molded by an extruding process and located at an inside of the synthetic resin outer conduit; and connecting portions for connecting adjacent inner conduits to each other, wherein looped curves or looped squares are formed through the plurality of inner conduits and the connecting portions in section and parts of each outer circumference of the inner conduits are fused on an inner circumference of the outer conduit.

[2] A device for manufacturing a synthetic resin tube with a plurality of inner conduits having hoppers for injecting raw materials therethrough and dices for extruding the injected raw materials comprising: a first extruding machine comprising a first dice for extruding the plurality of the inner conduits formed at a head of a screw case and having a plurality of inner blocks, a plurality of outer blocks separated from each inner block at a predetermined distance, and inner conduit connecting portions for connecting each outer block to each other, raw materials being injected into the gaps between the inner and outer blocks and the inner conduit connecting portions so as to form the plurality of the inner conduits having looped curves or looped squares; a first cooler for cooling the inner conduits, which are extruded and molded through the first dices of the first extruding machine, by means of water-cooling manner formed continuously at a rear portion of the first extruding machine; a second extruding machine continuously arranged in a rear of the first cooler and comprising a receiving pipe for receiving the inner conduits extruded through the first extruding machine and a second dice for molding an outer conduit of surrounding the inner conduits passing through the first extruding machine located at an end portion of the receiving pipe and having a plurality of inner blocks and outer blocks separated from each inner block at a predetermined distance, an admission part of the inner block being gradually narrowed inward and a discharging part of the inner block being gradually widened outward in diameter; and a second cooler for cooling the outer conduit by means of water-cooling manner continuously formed at a rear portion of the second extruding machine and having a set pattern dice for forming wrinkles at a circumference wall of the outer conduit extruded through the second dice.