JPS6195926A - Molding method of duct provided with resonator - Google Patents

Abstract

PURPOSE:To eliminate generation of an air leak resulting from a vibration of an engine, by a method wherein either one of a resonator and duct is molded, the other component is molded by containing this one component within a mold of the other component and both the components are unified. CONSTITUTION:A mold 11 for molding a resonator is constituted with a top force 12 and bottom force 13, and when blow molding is performed by making use of the top and bottom force 12, 13, the resonator 19 is molded. Blow molding of a duct 21 is performed by inserting parison into a space to be constituted with a cavity 20a of a top force 20 for molding a duct and a bending concave part 18 of a resonator 19. A monolithic article of the resonator 19 and duct 21 is unloaded from both the forces 13, 20, and a communication hole 23 is provided on a joint 22 by inserting a drill through a working hole 17a as it is. The resonator 19 and the duct 21 and unified by clogging the working hole 17a.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for forming a duct with a resonator.

BACKGROUND OF THE INVENTION Conventionally, a resonator and a duct have been coupled by a structure shown in FIG. That is, the resonator IK is formed with a fitting part 3 having a through hole 2t, and the fitting part 3 has a through hole 2t.
An annular recess 4 is formed in the 0 local area. On the other hand, a hole 6 is provided at a predetermined portion of the duct 5.
A grommet 7 is attached to the edge. Then connect resonator 1 to duct 5 I@! When attaching, the two members 1 are integrated by press-fitting the abbreviated notation part 3 into the grommet 7 and positioning the grommet 7 in the annular recess 4.

Problems to be Solved by the Invention However, in the conventional structure, the fitting portion 3t-
A process of molding the resonator l and the duct 5 and t-4 separately, a process of molding a hole 6 in the duct 5, a process of attaching a grommet 7 to the hole 6, and a process of press-fitting the fitting part 3 of the resonator 1 into the grommet 7. Process, etc., by hand? It requires many processes that require reliance on the ¥ industry. For this reason, there is a disadvantage that molding cannot be performed quickly and at a low cost, and when the resonator 1 and the duct 5 are moved in opposite directions due to engine vibration or traveling photography, the grommet 7 and the annular recess A gap was formed between the two, and there was a risk that air leakage would occur from the gap.

The present invention has been made in view of the conventional situation, and it is possible to reduce costs through a simple process, and
This invention provides a method for molding nine ducts equipped with a resonator that can completely eliminate the occurrence of air distortion caused by engine vibration etc. by integrally coupling the resonator and the duct.

Determined Means for Solving the Problems In order to solve the above problems, in the present invention, one of the members of the resonator and the duct to which the resonator is installed is molded in advance, and the molded One member is placed in a mold for molding the other member, and the other member is blow-molded to integrate the two members and form a predetermined communication hole at the joint of the two members. .

Function In the above configuration, the product includes a step of molding one of the resonator and duct members, a step of housing the two members in a mold and molding the other member, and a joining portion between the two members. It is molded through a simple and short process of providing a communicating hole in the. Furthermore, since both members are integrally joined during blow molding, there is no gap between the two members due to engine vibration, etc., and the occurrence of air leakage caused by engine vibration etc. can be eliminated. be.

Real sister example An embodiment of the present invention will be described below with reference to the drawings.

That is, as shown in FIG. 1(a), the resonator molding die 11 is composed of an upper die 12 and a lower die 13. A raised part 15 is provided, and a convex part 16 is formed at the center of the bottom inside the mandrel mold 13.

A plurality of grooves 15a and angular protrusions 15b are formed in the raised portion 15, as shown in an enlarged view in FIG.

When blow molding is performed using such upper and lower molds L2, 13'i, as shown in FIG.
As shown in FIG.
and hook portion 18i) are formed, and the resonator 19 is molded. In the next step, the resonator 19 is left in the lower mold 13 as shown in FIG. The parison is inserted into the space formed by the mold cavity 20a and the curved recess t$18 of the resonator 19, and the duct 2 is inserted as shown in Figure -Si).
1 is blow molded. At this time, as described above, since the curved recess 18 of the resonator 19 is provided with a plurality of protrusions 18 a and hook portions tab, as shown in FIG. a and hook part t
A strong joint n is formed between the curved recess 18 and the lower surface of the duct 21 by a physical bond in which the resin engages a b and a chemical bond caused by hardening of the resin. In the next step, as shown in FIG. 1(E), the resonator 19 and the duct 2 are
1, and use a drill etc. to make a working hole 17a in the recess 17 formed at the bottom of the resonator 19, and insert the re-drill into the working hole 17aJ as it is to communicate with the coupling device. A hole 23t is provided. Finally, fit the cap wing into the unnecessary t working hole 17a,
By closing the working hole 17 a), Fig. 1 (f)
The resonator 19 and duct 21 shown in t are integrated.
The product can be obtained (as mentioned above).

Since the steps other than attaching the caps 24t-1ff are mechanical processes, it is possible to speed up the process and reduce the cost of the product. Because they are integrated through both physical and chemical bonding, it is possible to obtain a product that is highly vibration resistant, with no gaps occurring between the two parts even when the engine is working in full force.

FIG. 5 shows another embodiment of the present invention, in which the duct is formed first. That is, by blow molding with the upper and lower molds 5 and 26, a stepped portion 21 is formed on the iron side as shown in FIG. 5(b).
A duct having a t 21 a ft is formed.

In the next step shown in FIG. 5(c), the step portions 21 a and 21 a t are placed on the upper walls of the upper mold portions of the upper and lower molds 27.4 for molding the resonator. -2
1t - fixed, resonator 1 as shown in 51st)
9t-pro 51 type. As a result, resonator 1
9 are molded with hook portions 19a, 19a that engage with the step portions 21a, 21a of the duct 21, so that the resonator 19 and the duct 21 are connected to the prow W shape of the resonator 19 as shown in FIG. 5(E). At the same time, the step portion 19a is chemically bonded.

19a and the hook parts 21a, 21a are combined so as to hold the duct 21. Therefore, the bonding strength between the resonator 19 and the duct 21 can be improved, and a product with poor image resistance can be obtained.

Note that as shown in FIG. 5(e), a communication hole is provided in the joint a of the resonator 19 and the duct 21, and
Working hole 17a used when providing the communication hole
is closed with a caps, as in the previous example.

DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention involves first molding either a resonator or a duct into which the resonator is installed, and then using the molded one member in a mold for molding the remaining other member. The other member was blow-molded to integrate the two members, and a predetermined communication hole was formed at the joining portion of the two members. Therefore, the resonator and the duct can be integrated in the molding process without manual work such as assembly via a grommet. Therefore, there is no need to assemble the two parts, making it possible to speed up the manufacturing process and reduce the cost of the product.In addition, since the two parts are chemically bonded together during blow molding, the bonding strength of the two parts is improved. By dramatically improving the same as above, it is possible to obtain a product that is excellent in excitation for dramatic photography without creating a gap at the joint between the two members due to engine vibration or traveling photography.

[Brief explanation of drawings]

Figures 1 (a), (b), hi, ni), (e), and (f) are process explanatory diagrams showing one embodiment of the present invention, and Figure 2 is an enlarged sectional view of the surface of the raised portion. Figure 3 shows the first factor (b), enlarged explanatory diagram of part A, Figure 4 shows diagram 1 (e), enlarged explanatory diagram of part B, and Figure 5 (
stomach). (B), et, B), and (E) are process explanatory diagrams showing other embodiments of the present invention, and FIG. 6 is a sectional view showing a conventional coupling structure of a resonator and a duct. ■1...Mold for molding resonator, 19...Resonator, upper mold for molding duct, 21...Duct,
n...Joining part, ru...Communication hole.

Claims (1)

[Claims] (1) Either the resonator or the duct in which the resonator is installed is molded in advance, and the molded one member is placed in a mold for molding the remaining other member to form the other member. A method for forming a duct equipped with a resonator, characterized in that both members are integrated by blow molding, and a predetermined communication hole is formed in a joint portion of both members.