JPS6329138Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a secondary air supply device installed in an air cleaner of an internal combustion engine for supplying secondary air to the exhaust system of the engine.

Summary of the invention The present invention provides a secondary air supply device having a secondary air filter attached to the wall of an air cleaner case for an internal combustion engine, and a secondary air intake pipe arranged inside the air cleaner case. By forming the secondary air suction pipe as a seamless integral molded product made of resin, and connecting this to the hole communicating with the front space of the secondary air filter via an elastomer grommet, This makes it easy to attach the secondary air intake pipe to the air cleaner case, and also prevents noise from leaking from the engine exhaust system.

Prior Art A conventional secondary air supply device had a configuration as shown in FIGS. 6 and 7. As shown in these drawings, a carburetor filter element 24
On the outer surface of the peripheral wall 1 of the air cleaner case housing the secondary air filter case 3, which has an outlet pipe 2, is arranged in a step 4' on its peripheral edge 4 for supplying secondary air to the exhaust system of the internal combustion engine. With the flange 5' of the filter element 5 that filters
It is installed in By doing so, the filter element 5 is crimped and fixed to the outer surface of the peripheral wall 1 while maintaining an airtight state. Peripheral wall 1
A recess 8 is provided in a portion facing the filter element 5, and a front space 9 is formed between the filter element and the recess 8.
0 is set. A metal plate 11 extends along the recess 8 and the inner surface 12 of the peripheral wall 1 adjacent thereto, and a flange portion 13 provided at the end thereof extends along the inner surface 14 of the bottom wall of the air cleaner case and the inner surface of the peripheral wall. 12 by processing means such as spot welding, thereby forming a secondary air intake pipe 1 having an air intake passage 15 to the filter element 5.
6 is formed by a part of the peripheral wall 1 and bottom wall of the air cleaner case, and a plate 11. The hole 10 in the recess 8 of the peripheral wall 1 forms a communication hole between the air suction passage 15 and the space 9 in front of the filter element.

Problems that the invention aims to solve In the first place, the main purpose of installing an air intake pipe in the secondary air filter is to muffle the noise generated by the exhaust system of the internal combustion engine that is supplied with secondary air. In the configuration of a conventional secondary air supply device, if there is an irregular gap between the peripheral wall inner surface 12 and the bottom wall inner surface 14 of the air cleaner case and the flange portion 13 of the plate 11, noise leaks through this gap and cannot be properly damped. Since the function could no longer be achieved, a sealing material was applied to such gaps to close the irregular gaps. Furthermore, in order to increase the amount of damping in the air suction pipe, it is necessary to increase the length of the air suction pipe, but increasing the length requires a large number of spot welds at the above-mentioned joint portion.

For the above reasons, conventional secondary air supply devices are expensive and have poor productivity.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a secondary air filter attached to the wall of an air cleaner case for an internal combustion engine, and a secondary air filter disposed inside the air cleaner case. In the secondary air supply device having an air suction pipe, the secondary air suction pipe is formed of a seamless integral molded product made of resin having an air suction opening at an end, and the secondary air suction pipe is A secondary air supply device is provided, characterized in that the secondary air supply device is connected to a hole communicating with the front space of the device via an elastomer grommet.

Embodiment Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

In the embodiment shown in FIGS. 1 to 3, the construction of the secondary air filter is the same as that of the conventional secondary air supply device described above, so a description thereof will be omitted. In FIGS. 1 to 3, reference numeral 17 is a seamless secondary air suction pipe made of resin and integrally molded into a bag shape by blow molding. Secondary air suction pipe 1
7 has an air intake opening 18 at one end, and an integrally formed support part 19 following this opening.
Inner surface 12 of peripheral wall 1 of the air cleaner case
It is fixed to by rivets 20. The secondary air suction pipe 17 further includes a bead portion 22 at the tip.
It is molded integrally with the connecting pipe portion 23 having
The connecting pipe portion 23 is connected to the hole 10 of the recess 8 forming the front space 9 for the filter element 5 through an annular grommet 21 made of an elastomer such as rubber having an annular groove on the outer periphery, as shown in the figure. Airtightly connected.

Note that the secondary air suction pipe 17 made of resin can be manufactured by separately manufacturing two halves by injection molding using a cutting die, etc., instead of blow molding, and then bonding the two halves. Further, in this embodiment, the secondary air filter is fixed to the outer surface of the peripheral wall 1 of the air cleaner case, but it can also be configured to be fixed to the inner surface of the peripheral wall 1.

As shown in FIG. 4, the secondary air suction device configured in this manner connects the outlet pipe 2 of the secondary air filter case 3 to a passage 26 such as a rubber hose with a reed valve 25 disposed in the middle and other passages. It is used by being connected to the exhaust system 28 of the internal combustion engine 27 via the exhaust system 28 of the internal combustion engine 27.

The noise generated by the exhaust system of an internal combustion engine supplied with secondary air propagates from the passage 26 through the outlet pipe 2 and the filter element 5, and from the connecting pipe 23 to the intake line in the secondary air intake pipe 17. , this suction tube is made in the form of a seamless bag, so
No sound is radiated from the suction pipe to the outside until it reaches the air suction opening 18, and a sufficient noise reduction effect can be achieved with a predetermined suction pipe length.

FIG. 5 shows a second embodiment of the present invention, in which a hole 10a in the recess 8 of the peripheral wall 1 of the air cleaner and a connection provided in the air suction pipe 17' so as to align with the hole 10a. The hole 29 is connected to an annular grommet 21 made of an elastomer such as rubber.
By inserting the air suction pipes 17' into these holes, the air suction pipe 17' is hermetically connected to the recess 8 forming the front space of the secondary air filter.

In each of the embodiments described above, the support portion 19 (see FIG. 1) of the secondary air suction pipe 17 is fixed to the inner surface 12 of the peripheral wall 1 of the air cleaner case with rivets, but it is fixed with bolts and nuts. Alternatively, it may be fixed to the inner surface of the peripheral wall using an adhesive.

Further, in these embodiments, the recess 8 forming the space in front of the secondary air filter in the peripheral wall 1 of the air cleaner case and the secondary air suction pipe 17 are connected at one place, but even if there are multiple connection points, the installation is still possible. It can be done easily.

Furthermore, the air intake opening 18 of the secondary air intake pipe
(See Figure 1) is located at one location, but the secondary air intake pipe is configured to extend on both sides along the peripheral wall 1 of the air cleaner case with the secondary air filter as the center, and air intake openings 18 are provided at two locations. You can.

Effects of the Invention As explained above, the present invention consists of a secondary air suction pipe that is made of resin and is made of a seamless integral molded product that is independent of the wall of the air cleaner case, and which is connected to the secondary air filter. By connecting the hole communicating with the front space via an elastomer grommet, the following effects can be achieved.

(1) Compared to conventional secondary air intake pipes that use part of the wall of the air cleaner case to form the air intake pipes, there is no irregular gap, so the desired sound deadening effect can be obtained, and the sealant can be There is no need to use it, it is highly productive, and it is inexpensive.

(2) In addition, compared to conventional secondary air suction pipes that use spot welding for installation, installation is extremely simple and there are no difficulties in installation processing, so productivity is excellent in this respect as well, resulting in low cost. Become something.

(3) By using elastomer grommets,
It is easy to connect the secondary air suction pipe to the hole communicating with the front space of the secondary air filter, and no noise leaks from the connecting part.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a sectional view taken along the - line in Figure 1, Figure 3 is a view taken in the direction of arrow C in Figure 1, and Figure 4 shows the state in which the secondary air supply device of the present invention is connected to the exhaust system of an internal combustion engine. 5 is a sectional view showing a second embodiment of the present invention, FIG. 6 is a sectional view of a conventional example, and FIG. 7 is a sectional view taken along the line - in FIG. 6. DESCRIPTION OF SYMBOLS 1... Peripheral wall of air cleaner case, 5... Filter element for secondary air, 8... Recess, 9
... Front space, 10 ... Hole, 17, 17' ... Secondary air suction pipe, 18 ... Air suction opening, 21,
21a...Annular grommet, 23...Connecting pipe, 2
9... Connection hole.

Claims (1)

[Scope of Claim for Utility Model Registration] A secondary air supply device having a secondary air filter attached to the wall of an air cleaner case for an internal combustion engine, and a secondary air intake pipe disposed inside the air cleaner case. , the secondary air suction pipe is formed of a seamless integral molded product made of resin having an air suction opening at the end, and the hole communicating with the front space of the secondary air filter is made of elastomer. A secondary air supply device characterized in that the secondary air supply device is connected via a grommet.