JPH0380091B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a synthetic resin intake pipe for an engine, and more particularly to a method for manufacturing a synthetic resin intake pipe having an intake passage and a heating fluid passage for heating the intake air.

Attempts have been made to form engine intake pipes from synthetic resin. This synthetic resin intake pipe is superior in terms of reducing the weight of the engine and preventing heating of the carburetor attached to the intake pipe due to the heat insulating effect of the synthetic resin. When a heated fluid passage is formed adjacent to the intake passage in order to promote vaporization and atomization, the synthetic resin partition wall between both passages prevents heat transfer from the heating fluid to the intake air, effectively discharging the intake air. The drawback is that it cannot be heated.

To solve the above-mentioned problems with synthetic resin intake pipes, the applicant proposed the following idea regarding ``engine intake pipes'' in an earlier application for utility model registration (Utility Model Application No. 81163/1983). did. This is the first
As shown in the figure, in an intake pipe C attached to an engine body A and to which a carburetor B is fixed, an outer cylinder D formed of synthetic resin and at least a part of the inner wall of the outer cylinder D are connected to a required air gap E. It is characterized in that it is provided with a metal inner plate F that holds and covers the space E, and a heated liquid is introduced into the space E. According to this intake pipe C, by introducing a heating fluid such as high-temperature engine cooling water or lubricating oil into the gap E, the intake air can be effectively heated through the metal inner plate F with excellent heat conductivity. can do. However, embedding the metal inner plate F that partitions the internal space during molding of the intake pipe C is difficult in terms of manufacturing technology.

The present invention aims to realize a new manufacturing method that can easily manufacture a synthetic resin intake pipe, particularly a synthetic resin intake pipe having an intake passage and a heating fluid passage partitioned by a metal plate. purpose.

That is, the method of the present invention is a method for manufacturing, by blow molding, a synthetic resin intake pipe for an engine in which an intake passage and a heated fluid passage are partitioned by a metal plate,
The metal plate is attached to an extrusion die that extrudes the parison, and a cylindrical parison surrounding the metal plate is extruded from the extrusion die. The parison is blow-molded by clamping the parison with a pair of slide molds, each of which is movable up and down and initially placed at a lower position, in the direction of sandwiching the parison. It is characterized in that a mounting flange is integrally formed at the lower end of the metal plate by moving it upward to the vicinity. According to such a method, it is possible to easily manufacture a synthetic resin intake pipe in which an intake passage and a heated fluid passage are provided on both sides of a metal plate, and a mounting flange is integrally formed.

Hereinafter, the present invention will be explained based on examples.

First, the molding device used in this example will be explained. As shown in FIGS. 2 and 3, the molding device includes a pair of split molds, which have mold surfaces 11 and 21 facing each other and are movable toward and away from each other. 10,20
, a parison extrusion die 30 disposed above both the split molds 10 and 20, and a blow pin 40 also disposed below the split molds 10 and 20, and
Recesses 12 and 22 are formed inside the lower part of 20, and a pair of slide molds 5 are inserted into the recesses 12 and 22.
0 and 60 are provided facing each other and slidable up and down, respectively.

The split mold 10, one of the pair of split molds 10 and 20, forms the side surface of the intake pipe to be manufactured on the intake passage side, and the mold surface 11 has a rectangular recess 13 in the center of the upper part. In addition, from both sides of the recess 13 to the end surface 14 facing the recess 12 in which the slide mold 50 is housed, an intake passage recess 15 having a semicircular cross section that branches into a plurality of branch parts 15a...15a. is formed, and each branch part 15
A concave groove 16 for a heated fluid passage extending from the center of the mold surface to the end surface 14 is formed at an intermediate position of a...15a. Then, the mold surface 11 is continuously raised from the upper edge of the recess 13 on the mold surface 11 to the edges closest to both sides of the intake passage groove 15 or along both edges of the recess 12. Cutting blade part 17
Further, the bottom surface of the recess 13 is provided with a hemispherical recess 13a in the center and holes 13b...13b in the four corners. Furthermore, the mold surface 51 of the slide mold 50 housed in the recess 12 of the divided mold 10 has one of the heating fluid passage grooves 16 and one of the intake passage grooves 15 adjacent thereto in the divided mold 10. A U-shaped groove 52 located so as to communicate the ends of the branch part 15a and the remaining branch part 1
Notches 5 located corresponding to the ends of 5a...15a, respectively
3...53 are provided so as to face the recess 12 from the upper end surface 54 of the slide mold 50. A cutting blade portion 55 is provided along the upper end of the mold surface 51 of the slide mold 50, the groove 52, and the periphery of the notches 53...53.

On the other hand, the other split mold 20 that is paired with the split mold 10 forms the side surface of the intake pipe to be manufactured on the heating fluid passage side, and as shown in FIG. A recess 23 whose contour corresponds to the outermost edges of the recess 13 and the groove 15 in the split mold 10 is provided, and the lower end thereof extends from the end face 24 into the recess 2 in which the slide mold 60 is housed.
2, and the recess 23 and the recess 22
A cutting blade portion 25 corresponding to the cutting blade portion 17 in the split mold 10 is provided on the periphery of the split mold 10 . Also,
The mold surface 61 of the slide mold 60 provided in the split mold 20 has U-shaped recesses corresponding to the U-shaped grooves 52, notches 53...53, and cutting blades 55 in the slide mold 50. Groove 62 and notch 63
...63 and a cutting blade portion 65 are provided.
In addition, notches 56 and 66 for inserting the blow pin 40 are provided at the lowest parts of the U-shaped grooves 52 and 62 in the pair of slide molds 50 and 60, and the recesses 13 in the pair of split molds 10 and 20 are provided. ,2
3 are provided with cutouts 18 and 26 for inserting a mounting portion 73 of a metal plate 70, which will be described later.

Further, the parison extrusion die 30 disposed above the split molds 10 and 20 has an outer cylinder 31 and an inner cylinder 32, as shown in FIG. A chuck member 3 is provided in the inner cylinder 32.
4 and a rod 35 for tightening and releasing the chuck member 34. When the rod 35 is lowered, the chuck member 34 grips and holds the tip of the attachment portion 73 of the metal plate 70 shown by the chain line.

In addition, in the above configuration, the pair of split molds 10,
20, the vertical movement of the slide molds 50 and 60 in each of the divided molds 10 and 20, and the vertical movement of the chuck operating rod 35 in the extrusion die 30, etc., are performed by a hydraulic cylinder, etc. not shown. .

Next, a process for manufacturing an intake pipe using the molding apparatus configured as described above will be explained.

First, as shown in FIG. 5a, the upper part of the metal plate 70 that partitions the intake passage of the intake pipe and the heating fluid passage is attached to a parison extrusion die, and then the die is inserted into a pair of split molds 10 and 20 facing each other in a separated state. hang between. As shown in FIG.
It has an external shape corresponding to the outermost edge of the split mold 10, and branches from the upper center to the left and right in correspondence with the grooves 15 and 16 of the split mold 10, and further branches into a plurality of branch parts 71a...71a. A concave groove 71 for forming an intake passage having a semicircular cross section (as viewed from the split mold 10 side) reaching the lower end, and a heating fluid passage provided from the center to the lower end at an intermediate position between the branch parts 71a...71a. Concave groove (viewed from the split mold 20 side)
72. Further, an elongated attachment part 73 is protruded from the upper part of the metal plate 70, and the tip of the attachment part 73 is gripped and held by the chuck member 34 of the extrusion die 30, as shown by the chain line in FIG. Therefore, the metal plate 70 is set as shown in FIG. 5a. Further, in the recess 13 of the split mold 10, as shown in FIG. 2, there is a carburetor mounting board 80 having a circular hole 81 in the center and screw shafts 82...82 protruding from the four corners. Each screw shaft 82...82 is connected to the hole 13b...1 in the recess 13.
3b.

Next, as shown in FIG. 5b, the extrusion die 30
A parison 90 made of semi-molten synthetic resin is extruded downward from the parison extrusion passage 33 at. This parison 90 is extruded into a flat cylindrical shape surrounded by the metal plate 70 according to the shape of the extrusion passage 33. When the parison 90 of the required length is extruded, air for blow molding is supplied to the parison 90 from the blow pin 40 provided below.
The split molds 10 and 20 located on both sides of the parison 90 as shown in FIG.
are brought close to each other together with slide molds 50 and 60 provided respectively. At this time, the parison 90 is expanded by the pressure of the air, and the expansion is transferred to the mold surfaces 1 of the divided molds 10, 20 and the slide molds 50, 60.
1, 21, 51, 61 and tightened. Therefore, on the side surface of the parison 90 on the side of the split mold 10, the recess 13, the grooves 15 and 16 in the split mold 10, the groove 52 in the slide mold 50, the notch 53, and the lower end surface of the split mold 10. 14 and the upper end surface 54 of the slide mold 50, respectively, are formed with bulges corresponding to the recesses 12, and on the side surface on the split mold 20 side, the recesses 23 in the split mold 20 and the recesses 23 in the slide mold 60 are formed. Concave groove 6
2. Notch 63 and lower end surface 24 of the split mold 20
and the upper end surface 64 of the slide mold 60.
bulges are formed corresponding to the respective bulges. When the split dies 10, 20 and the slide dies 50, 60 completely come into contact with each other, the corresponding cutting blades 17, 25 of the split dies 10, 20, as shown in FIGS.
and the corresponding cutting blades 55 and 65 in the slide molds 50 and 60, the portion 9 protruding from the recess or groove of each mold in the parison 90.
1 is bitten off and formed into an intake pipe contour shape that follows the shape of the cutting blade. At the same time, each bulge formed in the parison 90 and the metal plate 70 surrounded by the parison 90 cause the split mold 10 to
On the side, an intake passage 101 having a substantially circular cross section is formed by the bulge 92 along the groove 15 in the split mold 10 and the groove 71 in the metal plate 70, and the bulge 93 along the groove 13 and the metal plate A hollow carburetor mounting base 102 communicating with the intake passage 101 is formed by the upper part of the carburetor 70 . At this time, the carburetor mounting board 80 is embedded within the thickness of the bulged portion 93, and only the screw shafts 82...82 are exposed to the outside. On the side of the split mold 20, a heated fluid passage (space) 103 is formed by the bulge 94 along the recess 23 in the split mold 20 and the metal plate 70. Furthermore, the groove 72 in the metal plate 70
overlaps the bulge 95 of the parison 90 formed along the groove 16 in the split mold 10, forming a passage 104 communicating with the heated fluid space 103. In this case, the air ejected from the glow pin 40 is
From the U-shaped tube part 96 of the parison 90 formed by the shaped grooves 52 and 62, the inside of the hollow rectangular parallelepiped-shaped bulge part 97 formed by the recesses 12 and 22 in the split molds 10 and 20 is inserted. The fluid flows into the intake passage 101 through the carburetor mounting base 102 and the heating fluid passage 103 to promote the formation of the parison 90, and after the formation, the parison 9
A cooling hardening effect of 0 is performed.

After that, as shown in FIG. 5d, the divided molds 10 and 2 are
When the slide molds 50 and 60 respectively provided in
A rectangular parallelepiped-shaped bulge 97 formed along is crushed between the end surfaces 14, 24 of the split molds 10, 20 and the end surfaces 54, 64 of the slide molds 50, 60, resulting in a solid flat flange. A lower end portion of the metal plate 70 is embedded within the thickness of the flange 97'.

After the above steps, the split molds 10 and 20 are separated to form a molded product 100' as shown in FIG. 8. Then, an unnecessary part in this molded product 100', that is, a hollow part 98 corresponding to the depression 13a in the recess 13 of the split mold 10 shown by the chain line,
By removing the U-shaped tube portion 96 on the lower surface of the flange 97', the protrusions 99...99 formed by the notches 53, 63 of the slide molds 50, 60, and the attachment portion 73 on the metal plate 70, a screw shaft 8 is provided at the center of the upper part.
A hollow carburetor mounting base 102 from which 2...82 are protruded has an engine mounting flange 105 (97') at the lower end thereof, and an opening 10 on the lower surface of the flange can be accessed from inside the mounting base 102.
6...106, a multi-branched intake passage 101,
The intake passage 101 is partitioned by a metal plate 70 and has an opening 1 at the center of the lower surface of the flange 105.
An intake pipe 100 is formed which is provided with a heated fluid passage 103 having a heating fluid passage 103 having a diameter of 07.

In addition, the synthetic resin part that forms the outer shell of the intake pipe,
Improves the bond with the metal plate placed inside,
In addition, in order to ensure sealability between the passages 101 and 103 or between these passages 101 and 103 and the outside, adhesive is applied to the surface of a flange 74 provided around the metal plate 70 as shown in FIG. The flange 74 and the parison 90 around it are bonded together by applying an adhesive in advance, or a rubber seal (not shown) is attached to the periphery of the flange and the parison 90 is attached with an adhesive.
It is desirable to bond with. As the adhesive in this case, a polyamide adhesive is suitable in terms of heat resistance, gasoline resistance, and the like. In addition, the metal plate 70 has the following features in terms of thermal conductivity, gasoline resistance, etc.
Aluminum alloy, brass, etc. are suitable. Furthermore, synthetic resins
A polyamide resin reinforced with glass fiber is suitable, but other materials such as polybutylene terephthalate and polyphenylsulfone can also be used. Note that the shape of the heated fluid passage does not have to be as in the above embodiment, and may be formed by bringing a part of the bulge 94 of the parison 90 into close contact with the metal plate 70.

As described above, according to the present invention, a synthetic resin intake pipe in which an intake passage and an intake heating fluid passage are partitioned by a metal plate with good thermal conductivity can be easily manufactured by blow molding. As a result, an engine intake pipe that is lightweight, does not have an adverse effect on the carburetor, and can promote fuel vaporization and atomization can be provided at a low cost.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing a conventional synthetic resin intake pipe, FIG. 2 is a perspective view showing the structure and arrangement of the molding device and metal plate used to carry out the method of the present invention,
FIG. 3 is a perspective view showing the mold surface of one of the split molds in the molding device, FIG. 4 is an enlarged vertical sectional view showing the internal structure of the extrusion die in the molding device, and FIGS.
d is a vertical cross-sectional view showing each step in the embodiment of the present invention, FIG. 6 is an enlarged cross-sectional view taken along line ~ in FIG. 5 c, and FIG. 7 is a cross section passing through the blow pin in the state shown in FIG. 5 c. FIG. 8 is an enlarged vertical cross-sectional view of the main part taken at , and a perspective view of the intake pipe formed by this embodiment. 10, 20...Divided mold, 30...Extrusion die, 50, 60...Slide mold, 70...Metal plate, 90...Parison, 100...Intake pipe, 10
1...Intake passage, 103...Heating fluid passage, 10
5...Flange.

Claims (1)

[Claims] 1. A method for manufacturing a synthetic resin intake pipe for an engine by blow molding, in which an intake passage and a heated fluid passage are partitioned by a metal plate, in which the metal plate is attached to an extrusion die for extruding a parison, and A pair of split molds are arranged outside the parison to extrude a cylindrical parison surrounding the metal plate, and a pair of split molds are provided inside the lower part of both split molds so as to be movable up and down, and are initially placed at a lower position. The parison is blow-molded while the slide molds are clamped in the direction of sandwiching the parison, and the pair of slide molds are moved upward to near the lower end of the metal plate to attach the flange to the lower end of the metal plate. 1. A method for manufacturing a synthetic resin intake pipe for an engine, characterized in that it is integrally formed with.