JPH0732896Y2 - Anti-corrosion device for automobile silencer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a corrosion preventive device for a silencer for an automobile, which has a silencer body having a plurality of compartments and equipped with an inlet pipe and an outlet pipe.

2. Description of the Related Art Conventionally, in a silencer of an automobile, a plurality of compartments 03 are provided by a plurality of partition plates 02 in a silencer body 01 made of a hollow body as shown in FIG. 4, and a front engine is provided in the body 01. Inlet pipe 0 connected to the exhaust port of
4, the muffler pipe 05, and the outlet pipe 06 extending rearward are attached, the front portion of the outlet pipe 06 is bent downward, and a horizontal portion 07 having a small hole 011 formed on the outer periphery is formed,
In some cases, the tip opening 08 is located near the bottom 09 of the silencer body 01.

With the above configuration, the exhaust gas is introduced into the silencer body 01 by the inlet pipe 04, passes through the muffler pipe 05 and the like to be silenced, and is discharged from the outlet pipe 06 to the outside, but at that time, it is collected in the bottom portion 09 of the silencer body 01. The stored water 010 such as condensed water was also sucked into the outlet pipe 06 through the opening 08 and the small hole 011 on the outer periphery of the horizontal portion due to the negative pressure accompanying the flow of the exhaust gas, and was discharged to the outside together with the exhaust gas (actually, (See Japanese Laid-Open Publication No. 59-184315).

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the above-mentioned conventional technology, since the stored water accumulated inside the silencer body is removed to the outside together with the exhaust gas, it is necessary to prevent the occurrence of rust in the silencer body and prevent its corrosion. However, since the opening at the tip of the outlet pipe for introducing condensed water has the same circular cross-sectional shape as the rear part of the pipe, even if the opening is arranged on the bottom surface of the silencer body, However, most of the cross section of the exhaust gas often opens above the water surface, and the flow rate of exhaust gas passing through the outlet pipe is almost the same throughout the entire length of the pipe. There is a problem in preventing the silencer body from being corroded because the force is not sufficient and the water cannot be discharged quickly and residual water is generated.

Means and Actions for Solving the Problems The present invention overcomes the above-mentioned difficulties, and in order to reliably remove condensed water in the silencer body or stored water that has entered through the outlet pipe during car washing etc., the silencer body is divided by a partition plate. The inlet pipe from the engine and the outlet pipe extending rearward are mounted in the silencer body, and the front end of the outlet pipe in the silencer body is curved downward to open its front end. A portion located near the bottom of the silencer body, the exhaust gas entering the silencer body by the inlet pipe passes through each of the compartments, the silencer for a vehicle exhausted by the outlet pipe, in the outlet pipe While opening the front end forward A corrosion preventive device for a vehicle silencer, characterized in that a lateral dimension of a front end opening of the outlet pipe is made larger than a vertical dimension of the front end opening, and exhaust gas passes through the outlet pipe. At this time, when the tip opening of the outlet pipe is submerged in the stored water, the stored water is pushed into the pipe by the gas pressure in the silencer body,
Even when the opening projects above the water surface, the cross-sectional area of the opening is smaller than that of the other parts, so the flow velocity of the exhaust gas when passing through the opening is high, and the negative pressure is accordingly high. The stored water is sucked with a large force and discharged to the outside of the silencer body, and when there is no water stored inside the silencer body, the area of the outlet pipe opening is the cross-sectional area of the other portion of the outlet pipe. Since the flow resistance of the exhaust flow passing through the opening of the outlet pipe does not increase, the exhaust pressure is prevented from increasing and the engine output is prevented from decreasing.

Examples Examples will be described with reference to the drawings.

Reference numeral 1 is a silencer body composed of a hollow cylindrical body, inside of which two partition plates 2 and 3 are arranged to form sealed compartments 4, 5 and 6 which constitute a sound deadening chamber, and an engine (not shown). The inlet pipe 10 connected to the exhaust port of No. 2) penetrates through the front wall 7 of the silencer body 1, is inserted into and supported by the partition plates 2 and 3, and its rear end opens into the compartment 6.

Further, short muffler pipes 11 and 12 are inserted and supported in substantially the centers of the partition plates 2 and 3, respectively, and both ends of the pipes 11 and 12 are opened in the compartments 4,5 and 5 and 6, respectively. There is.

In the lower part of the silencer body 1, the vicinity of the front end opening 14 of the outlet pipe 13 having a circular cross section is inserted and supported by the partition plate 2, and the rear portion thereof is inserted and supported by the partition plate 3 and the rear wall 8 to support the silencer body 1. Extending to the rear of.
And the outlet pipe 13 is in the compartment 5,
The front portion is bent obliquely downward, and a horizontal portion 15 parallel to the bottom portion 9 of the silencer body 1 is formed at the front end portion thereof, and the tip opening portion 14 is placed on the bottom portion 9 or close to the bottom portion 9. The horizontal portion 15 provided and including the opening 14 is formed in a horizontally elongated flat shape in a cross section vertically compressed within a range in which the cross sectional area is not significantly reduced.

The front horizontal part of the outlet pipe 13 in the compartment 5
An appropriate number of small holes 16 are provided in the upper rear part of 15.

Since the present embodiment is configured as described above, exhaust gas is introduced into the compartment 4 inside the silencer body 1 from the front by the inlet pipe 10, and the exhaust gas filled in the compartment 6 is reversed to the muffler. Compartments via pipes 12, 11
The exhaust gas, which is sequentially introduced into the compartments 5 and 4, and fills the compartment 4 is reversed again and is discharged rearward from the opening 14 of the outlet pipe 13 opened near the bottom 9. In this way, the exhaust gas fills each compartment in the silencer body 1 and is silenced while passing through while reversing.

Then, when water is passed from the outside into the compartment 4 through the outlet pipe 13 by car washing or the like and is accumulated, or when condensed water is accumulated, the accumulated water is vaporized by the exhaust heat and together with the exhaust gas. Is discharged. At this time, the opening 14 of the outlet pipe 13 is located at the bottom 9 of the compartment 4.
Since it is located in the vicinity and has a horizontally long flat shape with a short vertical dimension, even if a small amount of water is stored, the opening 14 will be submerged in the stored water or there will be many parts below the water surface. The water is pushed out into the outlet pipe 13 by the gas pressure, and when the amount of stored water is small, or when the amount of stored water has decreased due to the drainage, the opening 14 projects above the water surface, but in that case as well. Since the cross-sectional area of 14 is smaller than the rear portion, the flow velocity of the exhaust gas when passing through the opening 14 becomes large, the negative pressure generated along with the flow becomes large, and the stored water is sucked and discharged with a large force.

Since the opening 14 is reduced to such an extent that the cross-sectional area does not decrease significantly, the resistance of the exhaust gas passing through the outlet pipe 13 does not increase significantly and does not hinder the exhaust action. .

Further, since the small hole 16 is provided in the upper rear portion of the horizontal portion 15 of the outlet pipe 13, the compartment 4 is used when the vehicle is washed.
When exhaust gas cannot pass through the opening 14 or is difficult to pass due to a large amount of water accumulated therein or the stored water being frozen, the exhaust gas is discharged through the small hole 16 to the outlet pipe 13 It can be guided inside and discharged outside.

3 (a), (b), (c), and (d) show a modified example of the tip 14 of the outlet pipe 13 shown in FIG. 1, and the cross sections thereof are elliptical 14a and eyebrows, respectively. A shape 14b, a heart-shaped 14c having a circular arc bottom, and a dish-shaped 14d are formed. In each case, a pipe having a circular cross section is compressed and formed in the vertical direction, and the above-mentioned effects can be obtained.

Each of the horizontal portions 15 is formed by vertically shortening the tip of one pipe bent downward, but the tip of the pipe bent downward is branched into a plurality of horizontal portions. You may make it form a part. If the sum of the cross-sectional areas of the plurality of horizontal portions is smaller than the cross-sectional area of the rear pipe, the horizontal portion has a low pressure and the water absorption is large, and the same effect can be obtained. Further, it is more effective if the horizontal portions are vertically shortened to have a horizontally long cross-sectional shape.

Effect of the Invention According to the invention of the present application, the front end of the outlet pipe in the silencer body is curved downward, the front end opening is located near the bottom of the silencer body, and the vertical dimension is shortened within a range that does not significantly reduce the opening area. Because it has been configured,
Even if condensed water or invading water such as when washing a car accumulates in the silencer body, the area of the opening that contacts these stored water becomes large,
A large amount of stored water can be easily discharged due to the gas pressure, and a higher negative pressure is generated due to the higher exhaust speed at the opening, and the suction force of the stored water is also increased, further improving drainage capacity. Can be increased. This is particularly noticeable when the engine speed is low and the exhaust gas flow rate is low.

Moreover, the flow resistance of the exhaust gas passing through the outlet pipe does not increase, and the flow resistance of the exhaust gas hardly increases, especially when water is not accumulated inside the silencer body. A decrease in engine output due to an increase in pressure can be avoided in advance.

As described above, since the stored water can be reliably removed to the outside of the silencer body, it is possible to reliably prevent corrosion of the silencer body due to the stored water.

[Brief description of drawings]

1 is a sectional view of a silencer according to the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, FIG. 3 is a modified sectional view of an opening of an outlet pipe, and FIG. 4 is a conventional silencer. FIG. 1 ... Silencer body, 2,3 ... Partition plate, 4,5,6 ... Compartment, 7 ... Front wall, 8 ... Rear wall, 9 ... Bottom part, 10 ... Inlet pipe, 11, 12 …… Muffler pipe, 13 …… Outlet pipe, 14 …… Opening part, 15 …… Horizontal part, 16…
... small holes.

Claims (1)

[Scope of utility model registration request] 1. A silencer body is divided into a plurality of compartments by partition plates, and an inlet pipe from an engine and an outlet pipe extending rearward are mounted in the silencer body, and the silencer body is provided in front of the outlet pipe. The portion is curved downward so that the front end opening is located near the bottom of the silencer body, the exhaust gas that has entered the silencer body by the inlet pipe passes through each of the compartments, and is discharged by the outlet pipe. In a vehicle silencer according to claim 1, the front end of the outlet pipe is opened forward, and the lateral dimension of the front end opening of the outlet pipe is larger than the vertical dimension of the front end opening. Silencer corrosion prevention structure.