JPH0737053B2 - Rib etc. forming method for resin coated steel pipe - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming ribs or the like on a resin-coated steel pipe in which a discontinuous rib made of resin, a floor, a connecting plate, etc. are integrally formed on the outer periphery of a long resin-coated steel pipe. Regarding

[0002]

2. Description of the Related Art Conventionally, this type of resin-coated steel pipe has been unsatisfactory.
As a method of forming continuous ribs, for example,
The method described in Japanese Patent No. 13173 is known.

According to this forming method, a synthetic resin is adhesively coated on the outer circumference of a thin steel pipe (thickness: about 0.7 mm) and the flat surface of the coating resin of the resin coating steel pipe extruded from the pipe extrusion device is While the synthetic resin in this part does not solidify, separate elliptical members are pressed at equal intervals to join to form a floor, or composed of a synthetic resin and a different synthetic resin extruded integrally from the pipe extruder. This is a method of pressing a shaped roll on the upper surface and the side surface of the floor portion while the synthetic resin in this portion is not solidified to form irregularities to form the floor portion, and to make the floor material for a livestock shed.

[0004]

However, in the above-mentioned conventional method of forming the floor portion on the resin-coated steel pipe, the resin coating of the steel pipe and the roll having an inner shape in which the resin is not yet solidified are used.
Since the formation of the floor by pressing is performed at the same time, the manufacturing speed is significantly reduced and the shape is comparable.
It is gentle and has no sharp angle, and it is required to engage with other members.
However, it is not suitable when the shape and accuracy are not obtained and the shape integrally formed with the coating resin is a discontinuous rib.

Further, the shape integrally formed with the coating resin is a discontinuous shape for integrally connecting a plurality of resin-coated steel pipes in parallel.
This is not possible in the case of connecting plates, etc.

[0006] Therefore, the present invention can improve the manufacturing speed and, despite the discontinuity of the shape ,
It is possible to form ribs, etc. on a standard resin-coated steel pipe ,
It is another object of the present invention to provide a method for forming ribs or the like on a resin-coated steel pipe that allows a plurality of long resin-coated steel pipes to be integrally connected in parallel.

[0007]

In order to solve the above-mentioned problems, the first method for forming ribs or the like on a resin-coated steel pipe according to the present invention is such that the upper and lower split surfaces of an injection molding die are split into both split surfaces. Is provided with a steel pipe engaging groove that allows the resin-coated steel pipe to be engaged with each other, and a cavity having a required shape such as a discontinuous rib on the split surfaces of the upper and lower molds communicates with the steel pipe engaging groove. After partially sandwiching the resin-coated steel pipe with the upper and lower molds,
A resin coating steel pipe is injected with a molten resin capable of heat fusion with the resin coating of the resin coating steel pipe, and the upper and lower molds are opened.
, Move it appropriately, close the upper and lower molds again, and seal the molten resin.
This is a method of repeating the step of injecting into the vity a required number of times .

Further, in the method of forming ribs or the like on the second resin-coated steel pipe, a plurality of resin-coated steel pipes are arranged parallel to each other in a state where both the divided faces of the upper mold and the lower mold of the injection molding die are in contact with each other. A plurality of steel pipe engaging grooves that can be joined are provided, and a cavity having a required shape that serves as a discontinuous connecting plate is provided on the opposing dividing surfaces between the adjacent upper and lower steel pipe engaging grooves. Provided in communication with the adjacent steel pipe engagement groove, and after partially sandwiching a plurality of resin-coated steel pipes by the upper and lower molds, inject the molten resin that can be heat-sealed with the coating resin of the resin-coated steel pipe into the cavity. Up, down
Open the mold and move each resin-coated steel pipe appropriately, and then again move up and down.
The process of closing the mold and injecting the molten resin into the cavité is required
It is a method of repeating several times.

[0009]

In the first means, the molten resin injected into the cavity is heat-sealed with the coating resin to form a long resin.
Discontinuous ribs or the like are intermittently formed on the coated steel pipe.

In the second means, the molten resin injected into the cavity is heat-fused with the coating resin of the resin coating steel pipe which is separated, and the plurality of long resin coating steel pipes are discontinuous.
The plates are intermittently connected in parallel with each other.

LD-PE (low density polyethylene) or PA (polyamide; nylon) is suitable as the coating resin for the resin-coated steel pipe and the molten resin that can be heat-fused with it.

[0012]

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

FIG. 1 is a perspective view of a clothes-hanging rod with a hanger obtained by a method of forming ribs or the like on a resin-coated steel pipe according to a first embodiment of the present invention.

The hanger hanging rod 1 has an adhesive polymer applied to the outer periphery of a thin circular steel pipe 2 having a wall thickness of about 0.7 mm, and a heat-bondable synthetic material such as LD-PE or PA-6. Long length with resin as adhesive coating 3
To the outer periphery of the resin-coated steel pipe 4, made of the same synthetic resin as the coating resin 3, without the extending trapezoidal radially outward of the resin-coated steel pipe 4, and Tsurana the axially serrated ruri The bumps 5 are integrally formed by heat fusion. Each rib 5 is provided with a through hole 6 through which a hook of a hanger (not shown) is passed, and each rib 5 is formed so as to have an air space 7 and be appropriately separated in the axial direction. There is.

In order to manufacture the above-mentioned clothes-hanger-hanging rod 1, as shown in FIG. 2, the split surfaces (PL) 11 and 12 of the upper mold 9 and the lower mold 10 of the injection molding die 8 are divided into both split surfaces. 11,
The semi-circular steel pipe engaging groove 1 that allows the resin-coated steel pipe 4 to penetrate through the injection molding die 8 to be engaged in the abutting state of 12
3 and 14 are provided to face each other, and a plurality of pairs of cavities 15 and 16 having a required shape to serve as the ribs 5 and the through holes 6 are provided on the dividing surfaces 11 and 12 of the upper and lower molds 9 and 10, respectively.
Provided in communication with 3, 14.

Then, as shown in FIG. 3, the toggle link mechanism 17 is used to close the upper and lower molds 9 and 10 to partially sandwich the long resin-coated steel pipe 4, and then the resin coating is applied from the injection device 18. LD-PE capable of heat fusion with the coating resin 3 of the steel pipe 4,
When a molten resin such as PA-6 is injected, the molten resin passes through the sprue 19 of the lower mold 10 and is maintained in a molten state by a built-in hot runner mechanism 20.
The ribs 5 and the through holes 6 are injected from 1 to each pair of the cavities 15 and 16, and the ribs 5 are integrated with the resin coating 3 of the resin coated steel pipe 4 by heat fusion.

After a series of ribs 5 and through holes 6 are formed, the upper and lower molds 9 and 10 are opened, the resin-coated steel pipe 4 is moved appropriately, and the upper and lower molds 9 and 10 are closed again. When the step of injecting the molten resin into the cavities 15 and 16 of each set is repeated a required number of times, a desired hanger-hanging article pole 1 is obtained.

Here, the toggle link mechanism 17 opens and closes the upper mold 9 to which the lower mold 10 is fixed, to which the end of the lever 22 having the fulcrum A on the side of the injection molding mold 8 as a rotation end is fixed. The first link 23 has one end pivotally attached to the fulcrum B above the upper die 9 and the other end of the second link 24 one end pivotally attached to the fulcrum C on the upper die 9. An end portion of a cylinder 25 having a base portion pivotally attached to a fulcrum E on the side of the fulcrum B is pivotally attached to the pivot point D.

In the mold opening operation by the toggle link mechanism 17, when the cylinder 25 is contracted, the pivot point D such as the other end of the first link 23 moves to the point F and the fulcrum of one end of the second link 24. C rotates about a fulcrum A of the lever 22 to a point G, and the mold opening is completed.

The mold closing operation is the reverse operation of the mold opening operation.

FIG. 4 is a perspective view of a stall floor material obtained by the method of forming ribs and the like on the resin-coated steel pipe of the second embodiment of the present invention.

In this livestock flooring 26, an adhesive polymer is applied to the outer periphery of a thin circular steel pipe 27 having a wall thickness of about 0.7 mm, and LD-PE or PA- is used as described above.
On the outer periphery of a long resin-coated steel pipe 29, which is adhesively coated with a heat-fusible synthetic resin such as 6 as the coating resin 28, the coating resin 2
Made of the same synthetic resin as in No. 8 and having a rectangular plate shape extending in the tangential direction of the outer circumference of the resin-coated steel pipe 29, and a plurality of flat portions 30 each having a set of three equally spaced in the axial direction. There is an air space 31 at an appropriate interval and is integrally formed by heat welding. Further, each flat surface portion 30 is made of a synthetic resin which can be heat-fused with the flat surface portion 30 and which is different from the synthetic resin and has excellent slip resistance. A cap-shaped floor portion 32 that covers the peripheral surface and the upper surface is integrally formed by heat fusion.

In order to manufacture the above-mentioned floor material 26 for livestock shed,
As shown in FIG.
The semicircular steel pipe engaging grooves 38, 39 that allow the resin-coated steel pipe 29 to be engaged with the split faces 36, 37 of the resin-coated steel pipe 29 through the injection molding die 33 when the split faces 36, 37 are in contact with each other. Are provided to face each other, and the dividing surfaces 36, 3 of the upper and lower molds 34, 35 are provided.
7, a plurality of pairs of cavities 4 having a required shape to form the flat surface portion 30
0 and 41 are provided so as to communicate with the steel pipe engaging grooves 38 and 39, respectively.

Next, although not shown, the same upper and lower molds 34 and 35 are used by using the same toggle link mechanism as in the first embodiment.
And partially sandwiching the long resin-coated steel pipe 29, and then injecting molten resin into the cavities 40 and 41 of each set from the injection device, each flat surface portion 30 is formed and
The flat surface portion 30 is heat-fused and integrated with the coating resin 28 of the resin-coated steel pipe 29.

Then, after the flat portions 30 of each set are formed intermittently over the entire length of the resin-coated steel pipe 29, the resin-coated steel pipe 29 is, as shown in FIG. 43 and the lower mold 44 are closed and sandwiched.

In this injection molding die 42, the resin-coated steel pipe 29 is penetrated through the injection molding die 42 in a state where the split surfaces 45, 46 of the upper die 43 and the lower die 44 are in contact with each other. Semi-circular steel pipe engaging grooves 47, 48 that are engaged with each other are provided to face each other, and the dividing surfaces 45 of the upper and lower molds 43, 44 are provided.
The flat portion 30 can be accommodated in the flat portion 46.
A plurality of pairs of cavities 49, 50 having a desired shape to form the floor 32 covering 0 are provided in communication with the steel pipe engaging grooves 47, 48, respectively.

When molten resin is injected from an injection device (not shown) into the cavities 49 and 50 of the upper and lower molds 43 and 44, which are closed by sandwiching the resin-coated steel pipe 29, each floor 32 is formed and the floor is formed. 32 are integrated by heat fusion and the flat portion 30, a return Ri Repetitive required number of times this step the desired barns flooring 26.

FIG. 7 is a perspective view of a double pipe obtained by a method of forming ribs and the like on a resin-coated steel pipe according to a third embodiment of the present invention.

The double pipe 51 is used as a rail for a farm track or a reinforcing material for a lightweight structure, and like the above-mentioned one, an adhesive polymer is attached to the outer circumference of a thin circular steel pipe 52 having a wall thickness of about 0.7 mm. And two parallel resin-coated steel pipes 54, 54 which are adhesively coated with a heat-fusible synthetic resin such as LD-PE or PA-6 as the coating resin 53. A rectangular plate made of the same synthetic resin, both resin coated steel pipes 5
A plurality of sets of connecting plates 55, which are one set of three and are spaced apart at equal intervals in the axial direction of 4, 54, are integrally formed by heat fusion in a space 56 having an appropriate interval. The connecting plate 55 may be a set of three continuous plates.

A thick portion 57 is provided at the joint of each connecting plate 55 with each resin-coated steel pipe 54 to increase the joint area with the coating resin 53 and enhance the joint strength. . The thick portion 57 may be provided only near the end of the connecting plate 55.

In order to manufacture the double pipe 51, as shown in FIG. 8, an upper die 59 and a lower die 6 of an injection molding die 58 are manufactured.
The two resin-coated steel pipes 54, 54 are separated from each other in parallel to the 0 division surfaces 61, 62 in a contact state of both the division surfaces 61, 62, and penetrate through the injection molding die 58 to be engageable. Two steel pipe engaging grooves 63, 64 are provided so as to face each other, and the upper and lower molds 59, 60 are separated from each other.
A plurality of pairs of cavities 65 and 66 having a required shape, which are the connecting plate 55 and the thick portion 57, are provided on the divided surfaces 61 and 62 facing each other between the steel pipes 3 and 64 so as to communicate with the steel pipe engaging grooves 63 and 64, respectively.

Next, as shown in FIG. 9, the toggle link mechanism 17 is used to close the upper and lower molds 59 and 60, and a long 2
When the molten resin is injected from the injection device 18 after partially sandwiching the resin-coated steel pipes 54, 54 of the book, the molten resin passes through the sprue 67 of the lower mold 60 and is maintained in a molten state by the built-in hot runner mechanism 68. Then, it is injected from the sprue gate 69 into each pair of cavities 65 and 66 to form the connecting plate 55 and the thick portion 57, and the thick portion 57 is heat-sealed with the coating resin 53 of the resin-coated steel pipe 54. The desired double pipe 51 is obtained by repeating this process a required number of times .

Since the structure and the effect of the toggle link mechanism 17 are almost the same as those shown in FIG. 3, the same constituent members are designated by the same reference numerals and the description thereof will be omitted.

Further, in each of the above-described embodiments, the case where the resin-coated steel pipes 4, 29, 54 are circular is described, but the present invention is not limited to this, and may be elliptical, quadrangular or other shapes.

Further, not only the case where two resin-coated steel pipes 54 are connected to form the double pipe 51, three or more may be connected in parallel, and the resin-coated steel pipes 54 are connected to the connecting plate 55. The vertical rib 70 shown by the chain double-dashed line may be integrally formed.

[0036]

According to the method for forming ribs, etc. for the first resin-coated steel pipe of the present invention as described above, according to the present invention, the injected molten resin is thermally fused and coating resin into the cavity, the length
Discontinuous ribs, etc. are formed intermittently on the length of resin-coated steel pipe.
Re Runode, it is possible to improve the manufacturing speed of the resin-coated steel pipe having a discontinuous rib or the like as compared with the prior art, regardless of the discontinuity of shape, the resin-coated steel pipe elongated
Ribs etc. for can be formed.

According to the second method of forming ribs or the like on the resin-coated steel pipe, the molten resin injected into the cavity is heat-fused with the coating resin of the resin-coated steel pipe which is separated from the cavity to form a long length.
Multiple resin-coated steel pipes of the
Parallel to intermittently connected Te is Runode, it can be integrally connected in parallel a plurality of resin-coated steel pipe elongated.

[Brief description of drawings]

FIG. 1 is a perspective view of a clothes hanging rod with a hanger according to a method of forming ribs and the like on a resin-coated steel pipe according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the main steps of the method for forming ribs and the like on the resin-coated steel pipe according to the first embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a molding apparatus used for carrying out a method for forming ribs and the like on the resin-coated steel pipe according to the first embodiment of the present invention.

FIG. 4 is a perspective view of a floor material for a livestock shed according to a method for forming ribs and the like on a resin-coated steel pipe according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of a previous step in the method for forming ribs and the like on the resin-coated steel pipe according to the second embodiment of the present invention.

FIG. 6 is a cross-sectional view of a post-process in the method for forming ribs and the like on the resin-coated steel pipe according to the second embodiment of the present invention.

FIG. 7 is a perspective view of a double pipe according to a method of forming ribs and the like on a resin-coated steel pipe according to a third embodiment of the present invention.

FIG. 8 is a sectional view of a main step of a method for forming ribs and the like on a resin-coated steel pipe according to a third embodiment of the present invention.

FIG. 9 is a schematic configuration diagram of a molding apparatus used for carrying out a method for forming ribs and the like on a resin-coated steel pipe according to a third embodiment of the present invention.

[Explanation of symbols]

 4 Resin Coated Steel Pipe 5 Rib 8 Injection Mold 9 Upper Die 10 Lower Die 11 Divided Surface 12 Divided Surface 13 Steel Pipe Engaging Groove 14 Steel Pipe Engaging Groove 15 Cavity 16 Cavity 29 Resin Coated Steel Pipe 30 Flat Surface 32 Floor 33 Injection Molding Mold 34 Upper mold 35 Lower mold 36 Dividing surface 37 Dividing surface 38 Steel pipe engaging groove 39 Steel pipe engaging groove 40 Cavity 41 Cavity 42 Injection mold 43 Upper mold 44 Lower mold 45 Dividing surface 46 Dividing surface 47 Steel pipe engaging groove 48 Steel Pipe Engagement Groove 49 Cavity 50 Cavity 54 Resin Coated Steel Pipe 55 Connecting Plate 58 Injection Mold 59 Upper Die 60 Lower Die 61 Dividing Face 62 Dividing Face 63 Steel Pipe Engaging Groove 64 Cavity 66 Cavity

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display area B29L 23:00

Claims (2)

[Claims] 1. A steel pipe engaging groove capable of engaging a resin-coated steel pipe in a state where both the divided surfaces are in contact with each other on the divided surfaces of an upper die and a lower die of an injection molding die, and an upper die and a lower die. Discontinuous on face
Cavities of a required shape, such as ribs, are provided so as to communicate with the steel pipe engaging grooves, and a long resin-coated steel pipe is partially sandwiched between the upper and lower molds, and then a resin coating of the resin-coated steel pipe is performed. A molten resin that can be heat-sealed is injected into the cavity, and the upper and lower molds are opened.
Move the resin-coated steel pipe appropriately and close the upper and lower molds again to melt it.
Repeat the process of injecting molten resin into the cavity a required number of times
Forming method such as a rib to the resin-coated steel pipe, characterized in that to. 2. A plurality of steel pipe engaging grooves that allow a plurality of resin-coated steel pipes to be engaged in parallel with each other in the abutting state of the divided surfaces of the upper die and the lower die of the injection molding die, and Cavities of the required shape to be discontinuous connecting plates are provided on the opposing dividing surfaces between the adjacent upper and lower mold pipe engaging grooves so as to communicate with the adjacent steel pipe engaging grooves. After partially sandwiching a plurality of long resin-coated steel pipes in the lower mold, inject the molten resin that can be heat-sealed with the coating resin of the resin-coated steel pipe into the cavity.
Then, open the upper and lower molds and move each resin coated steel pipe appropriately,
Close the upper and lower molds again and inject the molten resin into the cavity.
A method for forming ribs or the like on a resin-coated steel pipe, characterized in that the steps described above are repeated a required number of times .