JP3854278B2 - Extrusion head - Google Patents

Description

  The present invention relates to an extrusion head, and more particularly to an extrusion head that facilitates setup such as head assembly and cleaning of structural members, for example, for color change or resin change of an extruded cable.

  Conventionally, in extrusion molding in which a core resin such as an electric cable or the like is coated with a coating resin, it is necessary to stop line production and perform setup for a new type in order to switch the type of electric cable.

  In particular, in the extrusion head, in order to change the color of the cable or change the resin, it is necessary to perform setup such as head assembly and cleaning of components. It is necessary to replace the extrusion jig according to the shape and diameter of the cable to be changed.

  In the above setup, it is necessary not only to replace the extrusion jig, but also to remove and clean the coating resin adhering to the components such as the die and nipple of the head body and extrusion jig. The extrusion jig has to be disassembled and is complicated and troublesome, so that it takes a long time for the above setup. In addition, in order to make the wall thickness of the coating resin in the cable circumferential direction uniform, it is necessary to align the die and nipple. For this reason, the above-described setup work has caused a significant reduction in the operating rate of extrusion molding.

Therefore, in a conventional extrusion head, a nipple is held by a setting flange portion, and an extrusion molding jig such as an alignment bolt, a heater for heating, a holder, a die holder, a wedge ring, or the like related to the die and the die is attached to the setting flange. Development for improving the efficiency of the above-described setup work has been carried out by making the unit structure attached to the part and separating the unit structure from the crosshead body (see, for example, Patent Document 1).
JP-A-2-252523

  By the way, in the conventional extrusion head of Patent Document 1, since the extrusion molding jig is separated and independent from the head body as a unit structure, components of the unit structure are replaced after the unit structure is removed from the head body, Although it is easier to clean, the setting flange is attached to the crosshead body with multiple bolts, and the holder for fixing the die and die holder is attached to the setting flange with multiple bolts. There was a problem that it took time to set up. Furthermore, since the number of component parts of the extrusion jig is large, there is a problem that it takes time to replace parts and to perform cleaning work.

  Furthermore, since it is necessary to align the die from four directions with, for example, four alignment bolts provided on the outer periphery of the holder, there is a problem that fine adjustment is difficult and takes time.

  In addition, since the unit structure is attached to the front end surface of the crosshead body, there is a problem that the crosshead for extrusion becomes longer overall and it is difficult to make it compact.

  The present invention has been made to solve the above-described problems.

The extrusion head according to the present invention includes a unit part mounting hole having an inner peripheral surface in the shape of a tapered surface extending to the front side, a first introduction path for introducing a coating resin into the inner peripheral surface of the unit part mounting hole, A head body with
A die unit part that can be inserted into and removed from the unit part mounting hole, and includes a nipple part that allows a core wire to pass therethrough, and a die hole that is positioned in front of the nipple part and covers the core wire with a coating resin. and a die portion, said a two-piece construction of the half-shaped fixing the master core which allowed to attach and detach the rear end portion of the die portions, sandwiching the periphery of the rear portion of the nipple portion and the master core with positioning the die unit The outer peripheral part which has the shape of the taper surface which can be inserted in and removed from the taper surface formed in the inner peripheral surface of the unit part mounting hole, and the screw part which fixes to the head body at the rear end part of this outer peripheral part A dice unit unit comprising a cartridge and a unit;
Consists of
A second introduction path provided to introduce the coating resin into the cartridge from the first introduction path; and a second introduction path that communicates with the second introduction path and is provided between an inner periphery of the cartridge and an outer periphery of the master core; A first flow path configured to flow the resin to the rear side, a second flow path communicating with the first flow path and provided between the inner periphery of the master core and the outer periphery of the nipple portion; A third flow path provided between the outer periphery of the nipple part and the inner periphery of the die part so as to flow the coating resin into the die hole of the die part in communication with the flow path. To do.

  In the extrusion head according to the present invention, in the extrusion head, it is preferable that a spiral groove portion communicating with the second introduction path and the first flow path is provided on an outer periphery of the master core.

  In the extrusion head according to the present invention, it is preferable that in the extrusion head, the cross-sectional area of the first flow path gradually changes greatly as the distance from the second introduction path of the cartridge increases.

  In the extrusion head according to the present invention, it is preferable that the extrusion head includes an outer peripheral portion of the master core having a taper surface for retaining that is fitted to the inner periphery of the cartridge.

  As can be understood from the means for solving the above problems, according to the present invention, the die unit portion in which the nipple portion, the die portion, the master core, and the cartridge are unitized can be easily combined with a unit of the head main body at a time. Since it can be inserted into and removed from the tapered shape of the part mounting hole, setup work such as member replacement and cleaning can be easily performed in a short time.

  In addition, since the spiral groove portion communicating with the second introduction path and the first flow path is provided on the outer peripheral portion of the master core, the coating resin flowing from the second introduction path is made uniform in the circumferential direction of the master core through the groove portion. Therefore, it is possible to evenly and fully spread the entire first flow path from the groove portion.

  Further, since the cross-sectional area gradually changes greatly as the first flow path moves away from the second introduction path of the cartridge, the coating resin can be distributed evenly and sufficiently in the circumferential direction of the flow path.

  Further, since the coating resin is made to flow backward through the first flow path and then flows forward through the second flow path, the coating resin in the circumferential direction is increased in order to increase the flow distance of the coating resin. The flow state is made uniform so that the entire flow path is evenly distributed and the entire length in the longitudinal direction of the extrusion head can be shortened.

  Moreover, the nipple portion and the die portion are necessarily aligned when mounted on the master core and the cartridge, and the cartridge is automatically aligned by the taper shape of the outer peripheral portion and the taper shape of the unit unit mounting hole. . Furthermore, since the extrusion head can be made smaller overall than the conventional product, the diameter difference due to thermal expansion or the like is reduced, so that no center adjustment is required (non-centering).

  In addition, the two-part cartridge reduces the number of parts such as bolts, and the cone-shaped (tapered) member such as the cartridge and master core can be easily assembled and disassembled using a shock hammer. it can.

  Embodiments of the present invention will be described below with reference to the drawings.

  Referring to FIGS. 1 to 4, an extrusion head 1 according to this embodiment is an apparatus for coating a core resin such as an electric cable with a coating resin, for example, a housing as a head body. 3, in this embodiment, has a substantially cylindrical shape with a unit portion mounting hole 5 in the center, and in detail, a die unit portion 7 described later is detachably mounted in the unit portion mounting hole 5. .

  Further, a first introduction path 9 is provided on the upper side surface of the housing 3 in FIG. 1 for introducing the molten coating resin into the inner peripheral surface of the unit mounting hole 5.

  In addition, a resin introduction nozzle member 11 for supplying molten coating resin to the first introduction path 9 is provided on the upper side of the housing 3 in FIG. This nozzle member 11 has a substantially funnel shape as a whole, and a replacement nozzle portion 13 is provided on the inner surface of the nozzle member 11 so as to be fitted therein. Moreover, an introduction passage 13 </ b> A for guiding the molten coating resin to the first introduction passage 9 is formed in the replacement nozzle portion 13. In this embodiment, the replacement nozzle portion 13 is made of Teflon (registered trademark) resin.

  With the above configuration, the molten coating resin passes through the introduction passage 13 </ b> A formed inside the replacement nozzle portion 13 and is guided to the first introduction passage 9 formed in the housing 3.

  Next, the die unit unit 7 will be described in detail.

  As shown in FIGS. 1 and 2, the die unit portion 7 is located on the nipple portion 15 that allows the core wire to pass therethrough and on the front side of the nipple portion 15 (right side in FIGS. 1 and 2). A die part 19 having a die hole 17 for covering the core wire with a coating resin, a master core 21 for positioning and mounting the nipple part 15 and the die part 19, and a rear side of the master core 21 and the nipple part 15 The cartridge 23 is composed of a two-part structure 23 that is sandwiched and fixed from the outer periphery.

  Further, in this embodiment, the unit portion mounting hole 5 of the housing 3 has a tapered shape having a tapered surface 25 having an inclination angle θ extending forward (rightward in FIG. 1). The outer peripheral portion has a tapered shape having a tapered surface 27 having the same inclination angle θ that can be inserted into and removed from the tapered surface 25 of the unit portion mounting hole 5. In this embodiment, the inclination angle θ is 5 °.

  Further, when the cartridge 23 is mounted in the unit portion mounting hole 5, the rear side of the cartridge 23 protrudes rearward of the unit portion mounting hole 5. A screw portion 29 is provided on the outer periphery of the protruding portion. . In addition, a positioning bracket 31 for positioning the cartridge 23 as shown in FIGS. 1 and 4 is provided at the rear portion (left side in FIG. 1) of the housing 3 toward the center of the unit portion mounting hole 5. A positioning groove 33 that protrudes and engages with the positioning bracket 31 is provided on the rear end surface of the cartridge 23.

  Therefore, the die unit portion 7 is simply fixed to the housing 3 by the nut portion 35 that is positioned and mounted in the unit portion mounting hole 5 of the housing 3 by the positioning bracket 31 and the positioning groove portion 33 and then screwed into the screw portion 29. it can. On the other hand, the die unit portion 7 can be easily removed from the unit portion mounting hole 5 of the housing 3 to the front side simply by loosening the nut portion 35.

  In addition, the cartridge 23 having the above-described two-part structure is formed by combining two cartridges 23A and 23B having a substantially cylindrical shape and halving from the center, and the outer shape is tapered. A master core groove portion 37 in which the master core 21 can be mounted in order to sandwich and fix the master core 21 from the outer peripheral side, and a nipple portion groove portion 39 in which the nipple portion 15 can be mounted in order to sandwich and fix the nipple portion 15 from the outer peripheral side. Is provided. A taper surface 41 for preventing the master core 21 from coming off is provided on the tip end side of the master core groove portion 37.

  Further, the cartridge 23A is provided with a second introduction path 43 for introducing the coating resin flowing in from the first introduction path 9 of the housing 3 located at the upper part in FIG.

  The master core 21 has a substantially cylindrical shape, and a first flow path 45 communicating with the second introduction path 43 is formed between the outer peripheral surface of the master core 21 and the master core groove 37 of the cartridges 23A and 23B. It is configured to be. Further, an outer peripheral portion of the front end portion of the master core 21 is provided with a taper surface 47 for preventing slipping that narrows toward the front end so as to be fitted to the taper surface 41 of the cartridge 23.

  In addition, a spiral groove 49 communicating with the second introduction path 43 and the first flow path 45 is provided on the outer periphery of the master core 21, and the spiral groove 49 and the second introduction path are provided. Positioning pins 51 for positioning so as to communicate with 43 are inserted into positioning hole portions 53 provided so as to reach the inside of the master core 21 from the outer peripheral portion of the cartridge 23B.

  Further, the nipple portion 15 has a substantially cylindrical shape so that the right end portion in FIG. 1 is gradually narrowed, and a nipple hole 55 through which a core wire passes is provided at the center of the end portion. And mounted on the rear side of the inner periphery of the master core 21.

  Further, the die portion 19 is provided with a die hole 17 for covering the core wire coming out from the nipple hole 55 of the nipple portion 15 with a coating resin at the right end portion in FIG. It is located on the front side of the inner periphery and is screwed into the tip hole portion of the master core 21 with a screw portion 57.

  Further, a second flow path 59 communicating with the first flow path 45 is formed between the inner peripheral surface of the master core 21 and the outer peripheral surface of the nipple portion 15. Between the outer peripheral surface on the front end side and the inner peripheral surface of the die part 19, a third flow path 61 for communicating with the second flow path 59 and supplying the coating resin to the die hole 17 of the die part 19. Is formed.

  Further, as described above, since the spiral groove 49 communicating with the second introduction path 43 and the first flow path 45 is provided in the outer peripheral portion of the master core 21, the coating flowing from the second introduction path 43 is provided. Since the resin once reaches the entire outer circumference in the circumferential direction of the master core 21 through the groove portion 49, it contributes to evenly and sufficiently spreading from the groove portion 49 to the entire first flow path 45.

  In addition, since the first flow path 45 is configured to gradually change in cross-sectional area as the distance from the second introduction path 43 of the cartridge 23 increases, the portion far from the second introduction path 43 is covered. Since the resin tends to flow, the coating resin contributes to the entire flow path evenly and sufficiently.

  Further, the first flow path 45 moves to the second flow path 59 after moving to the rear side (left side in FIG. 1) opposite to the front side in which the coating resin flows in the second flow path 59. Thus, even if the length in the left-right direction in FIG. 1 is short, the flow distance of the coating resin is increased, which contributes to the coating resin being evenly distributed over the entire flow path.

  In summary, the die unit 7 in which the nipple portion 15, the die portion 19, the master core 21 and the cartridge 23 are unitized can be easily inserted into and removed from the taper shape of the unit portion mounting hole 5 of the housing 3 at a time. It is possible to easily perform setup operations such as member replacement and cleaning in a short time.

  In addition, since the coating resin is made to flow backward by the first flow path 45 and then flows to the front side by the second flow path 59, the flow distance of the coating resin becomes long, so that the circumferential direction is increased. Since the flow state of the coating resin is made uniform, the entire flow path is evenly distributed and the entire length in the longitudinal direction (front-rear direction) of the extrusion head 1 can be shortened, so that the entire structure can be made compact.

  In addition, the nipple portion 15 and the die portion 19 are inevitably aligned when mounted on the master core 21 and the cartridge 23, and the cartridge 23 is tapered on the outer peripheral portion of the taper surface 27 and the unit portion mounting hole 5 of the housing 3. 25 is automatically aligned. Furthermore, since the extrusion head 1 can be made compact and compact as a whole compared with the conventional product, the diameter difference due to thermal expansion or the like can be reduced, so that center adjustment is not required (non-centering).

  In addition, parts such as bolts are reduced by the cartridge 23 having a two-part structure, and a member having a cone shape (tapered shape having a tapered surface) such as the cartridge 23 and the master core 21 is used. Also, assembly and disassembly can be easily performed using a shock hammer or the like.

  In addition, this invention is not limited to embodiment mentioned above, It can implement in another aspect by making an appropriate change. In the present embodiment, an example of extrusion of an electric cable has been described. However, extrusion that can be widely applied to extrusion products such as multi-core flat wires, tape products, hollow pipe-like products such as hoses, and solid products such as strings and fibers. The head is included.

1 is a longitudinal sectional view of an extrusion head according to an embodiment of the present invention. 1 is a schematic exploded perspective view of an extrusion head according to an embodiment of the present invention. It is a right view of FIG. FIG. 2 is a partial left side view of FIG. 1.

Explanation of symbols

1 Extrusion head 3 Housing (head body)
5 Unit part mounting hole 7 Dice unit part 9 First introduction path 11 Nozzle member 13 Replacement nozzle part 15 Nipple part 17 Die hole 19 Die part 21 Master core 23, 23A, 23B Cartridge 25 Tapered surface (of unit part mounting hole 5)
27 Tapered surface (for cartridge 23)
29 Screw part (of the cartridge 23 and the nut part 35)
31 Positioning bracket 33 Positioning groove 35 Nut 37 Master core groove 39 Nipple groove 41 Tapered surface (of the master core groove 37)
43 2nd introduction path 45 1st flow path 47 Tapered surface for omission prevention (of master core 21)
49 Spiral groove 51 Positioning pin 53 Positioning hole 55 Nipple hole 57 Threaded portion (of die portion 19 and master core 21)
59 Second channel 61 Third channel

Claims (4)

A unit part mounting hole (5) having an inner peripheral surface in the shape of a tapered surface (25) extending to the front side, and a first introduction path for introducing a coating resin into the inner peripheral surface of the unit part mounting hole (5) ( 9), and a head body (3) comprising:
(3) A die unit portion (7) that can be inserted into and removed from the unit mounting hole, and a nipple portion (15) that allows a core wire to pass therethrough, and the core portion that is located in front of the nipple portion (15). die section having a die hole (17) covering the coating resin to the line (19), and the master core (21) which allowed to attach and detach the rear end portion of the die portion (19) with positioning the die unit (19), The taper formed on the inner peripheral surface of the unit portion mounting hole (5) is a half- divided structure in which the master core (21) and the rear portion of the nipple portion (15) are sandwiched and fixed from the outer periphery. A cartridge having an outer peripheral portion in the shape of a tapered surface (27) that can be inserted into and removed from the surface (25) and a screw portion (29) that is fixed to the head body (3) at the rear end portion of the outer peripheral portion. (23) Phased dice unit section (7),
Consists of
A second introduction path (43) provided to introduce the coating resin into the cartridge (23) from the first introduction path (9), and the second introduction path (43) communicated with the cartridge (23). A first flow path (45) provided between the inner periphery and the outer periphery of the master core (21) and configured to flow the coating resin backward, and communicated with the first flow path (45) A second flow path (59) provided between the inner periphery of the master core (21) and the outer periphery of the nipple part (15), and the die of the die part (19) communicating with the second flow path (59) A third flow path (61) provided between the outer periphery of the nipple portion (15) and the inner periphery of the die portion (19) for flowing the coating resin in the hole (17) is provided. Extruding head. The outer circumference of the master core (21), according to claim 1, characterized by being provided with a helical groove which communicates with the second introduction passage (43) the first flow path (45) (49) Extrusion head. The first flow path (45), according to claim 1 or 2 extrusion head according to, characterized in that gradually by the cross-sectional area larger contain altered as the distance from the second introduction path of the cartridge (23). The outer peripheral part of the said master core (21) is provided with the taper surface (47) for prevention of a fitting fitted to the inner periphery of the said cartridge (23), The one in any one of Claims 1-3 characterized by the above-mentioned. Extrusion head.

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