JP3012486U - Multi-layer inflation film molding die - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide the market with an inflation film forming die capable of integrally connecting mandrels arranged concentrically with a desired torque by improving a fastening tool. [Structure] Inner layer mandrel 21, the mandrel 23 for the intermediate layer and the mandrel 24 for the outer layer are concentrically and closely in contact with each other, and are superposed and fitted to each other. The connection ring 25 and the outer layer mandrel 24 that are concentrically overlapped on the inner layer mandrel 21 are sandwiched between the inner and middle layer mandrels 21 and 23 with a common fastening tool (50, 51) from above and below, Combined so that they can be disassembled freely. The lower surface of the connecting ring 25, the inner layer mandrel 21, and the intermediate layer mandrel 2
A confluent resin passage 26 that connects the cylindrical resin passages 11, 12, and 13 to a single annular discharge port 37 is formed in a gap between the cylindrical resin passages 3 and the upper portion of the outer layer mandrel 24.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a die for forming a tube film by an inflation method, and more particularly to a large die for forming a multi-layer film (for example, an annular discharge port diameter of 1000 mm to 3000 mm for molten resin).

[0002]

[Prior art]

 Various types of multi-layer inflation film forming dies have been developed.

[0003]

[Problems to be solved by the device]

 At present, long bolts are used to connect the inner layer mandrel and the intermediate layer mandrel to the outer layer mandrel. Cannot obtain a large tightening torque. Also, as shown in Fig. 2 of Japanese Utility Model Publication No. 61-28512, each adjacent mandrel is fastened with a short bolt, and finally the die base is bolted to the die body to form a multilayer inflation film forming die. However, this complicates the die structure and increases the manufacturing cost. Furthermore, in the case of a large die, the number of tightening bolts reaches dozens, and the tightening structure becomes more complicated. This invention improves the above-mentioned drawbacks and improves the fasteners so that these mandrels can be integrally connected with a desired torque, and the number of fasteners is reduced even in a large die. The objective is to provide the market for an inflation film forming die that can be manufactured.

[0004]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a specific device is to connect a multiple resin supply passage to a multiple cylindrical resin passage through each radial distribution passage, and further connect the multiple cylindrical resin passages to a single annular discharge port through a confluent resin passage. In a multilayer inflation film forming die that is made to communicate with each other, the innermost layer mandrel, the intermediate layer mandrel, and the outermost layer mandrel are concentrically sequentially overlapped with each other inside and outside, and mutually fitted to form a gap between the peripheral surfaces of the die adjacent to the inside and outside. The cylindrical resin passages for the innermost layer and the intermediate layer are formed on the innermost layer, and the distribution passages are vertically and closely stacked in the innermost layer mandrel, the intermediate layer mandrel, and the outermost layer mandrel. It is formed substantially horizontally on the mating surface of the horizontal part, and the connecting ring and the outermost layer mandrel that are concentrically stacked on the horizontal part of the innermost layer mandrel are the Inner and middle layer mandrels are clamped from the top and bottom by a common fastening tool, and they are integrally disassembled, and the lower surface of the connecting ring and the innermost layer mandrel, intermediate layer mandrel, and outermost layer mandrel are connected. The multi-layer inflation film molding die is characterized in that the confluent resin path is formed in a gap from the upper part.

In order to solve the above-mentioned problems, the tightening tool in the inflation molding die includes a plurality of tightening bolts which are passed through the connecting ring and the innermost layer mandrel from the side of the connecting ring, and a lower end portion of the bolts. Assembling and disassembling of these dies shall have a female screw that is screwed to the upper end, and a socket that is inserted into the mandrel for the innermost layer, the mandrel for the intermediate layer, and the mandrel for the outermost layer from the mandrel for the outermost layer. Above all preferred.

In order to solve the above problems, the molding die is for inflation film molding of 3 types and 3 layers, the feeder body is connected to the molding die, and the cylindrical resin passage of the outer layer is of the feeder body. The side feed resin passage is communicated with the molding die through the radial distribution passage, and the intermediate layer cylindrical resin passage is communicated with the center feed resin passage of the feeder body through the molding die radial distribution passage. The cylindrical resin passage of the inner layer communicates with the second side feed resin passage of the feeder main body through the radial distribution passage of the molding die, and the upper surface of the connecting ring is a substantially flat surface and the upper ring is screwed to this upper surface. The outer peripheral surface of the upper ring and the die body forming the annular discharge port are arranged so as to surround the outer peripheral surface of the mandrel for the outer layer. It is on the resin distribution preferably fixed via the tightening ring on the lower surface of the.

[0007]

[Action]

 In the invention according to claim 1, after stacking the mandrel for the intermediate layer, the mandrel for the innermost layer, and the connecting ring above and below the mandrel for the outermost layer in this order, the common ring and the connecting ring are connected to each other. The mandrel for the innermost layer and the mandrel for the intermediate layer are fastened together from above and below with the mandrel for the outermost layer so as to be integrally connected to each other to form the multiple cylindrical resin passage, the merged resin passage and the distribution passage. To disassemble, reverse the above procedure. When manufacturing a multi-layer blown film, molten resin is supplied from multiple resin channels, and these molten resins are distributed by radial distribution channels, supplied to corresponding multiple cylindrical resin channels, and merged at the confluent resin channel to form a discharge port. More pushed out.

According to the second aspect of the invention, in addition to the function of the first aspect of the invention, the tightening bolt is screwed into the socket inserted from below, and the connection ring and the outermost layer mandrel are connected to each other. Then, tighten the innermost layer mandrel and the intermediate layer mandrel to join them together.

According to the third aspect of the invention, in addition to the function of the first aspect of the invention, three types of melts supplied from the feeder main body to the molding die by the center feed method or the side feed method are used. After the resin is supplied to the corresponding cylindrical resin passages in a one-to-one correspondence through the triple resin supply passage and the distribution passage, the resin is joined by the joining resin passage to form a three-kind three-layer inflation film.

[0010]

【Example】

 Next, a typical embodiment of the invention described in claims 1 to 3 will be described. In FIG. 1, A is an inflation film molding die of three types and three layers, a feeder body B is connected to the molding die A, and the cylindrical resin passage 10 of the outer layer is a side feed resin of the feeder body B. The passage 30 communicates with the outer layer resin supply passage 60 formed in the outer layer mandrel 24 of the molding die A and the radial direction distribution passage 31. The intermediate layer cylindrical resin passage 11 is connected to the center feed resin passage 32 of the feeder main body B. In addition, the intermediate layer resin supply passage 61 formed in the intermediate layer mandrel 23 in the molding die A and the radial direction distribution passage 33 communicate with each other, and the inner cylindrical resin passage 12 is connected to the second main body B of the feeder main body B. The side feed resin passage 34 is communicated with the inner layer resin supply passage 62 formed in the inner layer mandrel 21 of the molding die A and the radial distribution passage 41. The upper surface of the connecting ring 35, which will be described later, is a substantially flat surface, and the upper ring 36 is screwed onto this upper surface. The mandrel 24 is arranged so as to surround the peripheral surface of the mandrel 24, and the outer layer mandrel 24 is fixed to the lower surface of the die body 38 via a tightening ring 39.

The inner layer mandrel 21 and the intermediate layer mandrel 23 each have a ring-shaped fitting portion 40 formed at the center of the flat lower surface, and these ring-shaped fitting portions 40 fit together to form the inner layer mandrel 21. The mandrel 23 for the intermediate layer and the mandrel 24 for the outer layer are concentrically sequentially overlapped inside and outside and sequentially fitted, and the cylindrical resin passages 11 and 12 for the inner layer and the intermediate layer are formed on the circumferential surface between the adjacent mandrels. A cylindrical resin passage 13 for the outer layer is formed between the outer surface of the outer layer mandrel 24 and the die main body 38. Spiral grooves are formed in the cylindrical resin passages 11, 12, and 13 of each of the layers to evenly distribute the molten resin.

The radial distribution passages 31, 33, 41 are horizontally formed in the corresponding mandrels 24, 23, 21 in horizontal portions which are vertically and closely overlapped with each other. The connecting ring 25 and the outer layer mandrel 24, which are concentrically fitted on the inner layer mandrel 21 and are superposed on the horizontal portion, are commonly used together with the inner layer mandrel 21 and the intermediate layer mandrel 23 in a tightening tool (50). , 51), which is held from above and below, and is integrally and disassembleably coupled to form a gap between the lower surface of the connecting ring 25 and the upper portions of the inner layer mandrel 21, the intermediate layer mandrel 23, and the outer layer mandrel 24. A confluent resin passage 26 is formed to connect the three concentric cylindrical resin passages 11, 12 and 13 to the single annular discharge port 37. At this time, an annular fitting portion 40 is formed at the center of the lower surface of the connecting ring 25 so as to be fitted to the inner layer mandrel 21. The tightening tools (50, 51) are composed of dozens of tightening bolts 50 that are passed through the connecting ring 25 and the inner layer mandrel 21 from the connecting ring 25 side, and a male screw 54 formed at the lower end of the bolt 50. A female screw 56 to be screwed is provided at the upper end, and the inner layer mandrel 21, the intermediate layer mandrel 23, and the outer layer mandrel 24 are provided with a socket 51 which is passed from the outer layer mandrel 24 side. A hexagon socket wrench (not shown) is provided on the top surface of the bolt 50. About 40 to 50 such fasteners are used for the molding die A. In the illustrated one, basically three fasteners are provided at one tightening point in the radial direction of the molding die A. (See FIGS. 1 and 2). An air suction / discharging pipe 70, which is parallel to the axial direction of the molding die A and penetrates through the molding die A, is provided similarly to a normal inflation film molding die (see FIG. 2).

The lower end of each socket 51 is fixed to the lower surface of the outer layer mandrel 24 with a set screw (not shown). When the operation of the extrusion molding machine is stopped as needed and the molding of the inflation film is interrupted, the cylindrical resin passages 11, 12, 13 communicating with the annular discharge port 37 are forcibly cooled. There may be a case where a fluid cooling section (not shown) is provided in the intermediate layer mandrel 23 of the molding die A 1.

That is, at the intermediate position between the two cylindrical resin passages 11 and 12, the fluid cooling portion is formed in a cylindrical shape concentric with the cylindrical resin passages 11 and 12, and the fluid cooling portion is small. Both spiral grooves are formed with two spiral grooves, both ends of which are open to the outside of the forming die A, and the two spiral grooves communicate with each other inside the intermediate layer mandrel 22. A cold air supply pipe for supplying cold air (a kind of cooling fluid) circulating in the spiral groove is connected to one of the both ends of the groove, and the other end has an outlet for the cold air. There is. At the time of interruption of the inflation film molding of 3 layers of 3 types, in order to reduce the temperature of the molten resin remaining in the cylindrical resin passages 11 and 12 to such an extent that the residual molten resin does not burn, the circulating cold air is used. An air hose (not shown) is connectable to the cold air supply pipe when cooling each cylindrical resin passage. Although the molding die has three layers of three types in the above embodiment, the invention is not limited to this in the inventions described in claims 1 and 2, and various types of multi-layers may be used.

[0015]

[Effect of device]

 In the invention according to claim 1, after the mandrel for the intermediate layer, the mandrel for the innermost layer and the connecting ring are vertically stacked above the mandrel for the outermost layer in this order, the connecting ring is attached by a common fastener. The innermost layer mandrel and the intermediate layer mandrel can be integrally fastened with a predetermined torque from above and below between the outermost layer mandrel and the outermost layer mandrel, and the multiple cylindrical resin passages, confluent resin passages, and distribution passages can be formed. .

According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, the tightening tool is connected to the upper connecting ring and the innermost layer mandrel from the common connecting ring side. By screwing the tightening bolt that is passed through and the socket that is passed from the outermost layer mandrel side, all mandrels, that is, the innermost layer mandrel, the intermediate layer mandrel, and the outermost layer mandrel can be fastened at the same time. . Further, since this socket has a long under-neck size, the under-neck size of the tightening bolt may be short, a large torque can be easily applied to the bolt, and the tightening and loosening operations can be easily performed.

According to the third aspect of the invention, in addition to the effects similar to those of the first and second aspects of the invention, an inflation film of three types and three layers can be appropriately formed.

As an effect peculiar to the embodiment, the fluid cooling portion is formed in a cylindrical shape concentric with the cylindrical resin passages at an intermediate position between the two cylindrical resin passages, and the fluid cooling portion has two sections. The both ends of the spiral groove are open to the outside of the molding die A, and one end of the both ends is cold air (cooling fluid A cold air supply pipe for supplying the cold air is supplied to the spiral groove from the cold air supply pipe, and the other end is used as an outlet for the cold air. It can be flowed while moving, and the molten resin remaining in each cylindrical resin passage can be forcibly cooled during this. By cooling in this way, the air whose temperature has risen is exhausted from the exhaust port to the outside of the molding die A, and deterioration of the residual molten resin and graphitization can be prevented when the operation is stopped.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of an example.

2 is a partial bottom view showing the arrangement of the fasteners of FIG. 1. FIG.

[Explanation of symbols]

 A molding die

Claims (3)

[Scope of utility model registration request] 1. A multi-layer inflation system in which a multiple resin supply passage is connected to a multiple cylindrical resin passage via each radial distribution passage, and further the multiple cylindrical resin passage is connected to a single annular discharge port via a confluent resin passage. In the film forming die, the mandrel for the innermost layer, the mandrel for the intermediate layer and the mandrel for the outermost layer are concentrically and sequentially overlapped with each other inside and outside, and are fitted together to form the innermost layer and the intermediate layer between the peripheral surfaces of adjacent dies Each of the cylindrical resin passages is formed, and the distribution passages are formed in the innermost layer mandrel, the intermediate layer mandrel, and the outermost layer mandrel, and are substantially aligned with the mating surfaces of the horizontal portions which are vertically and closely stacked. The connecting ring, which is formed horizontally and is concentrically overlapped on the horizontal portion of the innermost layer mandrel, and the outermost layer mandrel, coexist with the innermost and intermediate layer mandrels. It is clamped from above and below by a common fastening tool and is integrally and disassembleably coupled.In the gap between the lower peripheral surface of the connecting ring and the upper part of the innermost layer mandrel, the intermediate layer mandrel, and the outermost layer mandrel, the confluent resin path is formed. A die for forming a multi-layer inflation film, characterized in that 2. The tightening tool comprises a plurality of tightening bolts which are passed through the connecting ring and the mandrel for the innermost layer from the side of the connecting ring, and an internal thread which is screwed to a lower end portion of the bolts at an upper end, The multi-layer inflation film molding die according to claim 1, comprising a mandrel for the innermost layer, a mandrel for the intermediate layer, and a socket which is inserted into the mandrel for the outermost layer from the side of the mandrel for the outermost layer. 3. The molding die is for inflation film molding of 3 layers of 3 types, a feeder body is connected to the molding die, and the cylindrical resin passage of the outer layer is a side feed resin passage of the feeder body. Through a radial distribution path of the molding die, the cylindrical resin path of the intermediate layer communicates with the center feed resin path of the feeder main body through the radial distribution path of the molding die, and the cylindrical resin path of the inner layer 2 side feed resin passages through the radial distribution passages of the molding die, the upper surface of the connecting ring is a substantially flat surface, and the upper ring is screwed to the upper surface, and the outer peripheral surface of the upper ring is And the die body forming the annular discharge port are arranged so as to surround the outer surface of the outer layer mandrel, and the outer layer mandrel is fixed to the lower surface of the die body via a tightening ring. Claim 1 or 2 inflation film molding die, wherein the being.