JPH0324823Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Technical field of the invention The present invention relates to an exhaust system for a freight vehicle. More specifically, the present invention relates to improving the exhaust performance of an exhaust system for an internal combustion engine mounted on a freight vehicle.

(b) Background of the technology In the exhaust system of internal combustion engines installed in freight vehicles, mufflers and other components tend to become more complex due to noise countermeasures, etc., and as a result, exhaust pressure increases and exhaust performance deteriorates. I'm getting used to it.

Therefore, there is a strong desire to develop means for improving exhaust performance.

(c) Prior art and problems FIG. 4 shows a conventional example of means for improving exhaust performance.

In this conventional example, a tail pipe 2 is erected close to the rear of a cab 1 of a truck, and a tail end 2a of the tail pipe 2 is made to protrude above the cab 1.

According to this conventional example, since the tail pipe 2 does not extend to the rear of the truck body, the overall length of the tail pipe 2 is shortened, and the exhaust pressure can be reduced. Further, the tail end 2a of the tail pipe 2 is brought into contact with the vehicle speed wind that collides with the cab 1 and rises, and the exhaust gas is drawn out by the vehicle speed wind, thereby reducing the exhaust pressure.

However, according to this conventional example, water or the like may enter the vertically installed tail pipe 2 and cause clogging, thereby increasing the exhaust pressure. Further, the direction of the vehicle speed wind is influenced by the speed of the truck, the height of the loading platform behind the cab 1, etc., and the effect of drawing out the exhaust gas due to the vehicle speed wind is unstable.

Incidentally, conventional examples of using vehicle speed wind include those shown in Japanese Utility Model Application Publications No. 57-107827 and No. 57-118929. It is not directly related to.

(iv) Purpose of the invention In view of the problems of the conventional example described above, the object of the invention is to provide an exhaust system for a freight vehicle that can reliably reduce exhaust pressure and improve exhaust performance.

(e) Structure of the invention In order to achieve this object, the exhaust system for a freight vehicle according to the present invention is an exhaust system for a freight vehicle in which the tail pipe of the internal combustion engine installed is erected close to the rear of the cab. At the top of the cab, a flat vehicle speed wind guide tube is installed in the longitudinal direction of the vehicle, with an intake opening expanding in the lateral direction of the vehicle and an exhaust opening narrowing.
The exhaust port side of the wind guide tube is sequentially inclined upward, and a tail pipe is passed through the wind guide tube, and the tail end of the tail pipe is directed toward the exhaust port side.

(F) Embodiment of the invention Hereinafter, an embodiment of the exhaust system for a freight vehicle according to the invention will be described based on FIG. 1. Components that are the same as those in the conventional example described above are given the same reference numerals, and a description of their structure will be omitted.

In the figure, reference numeral 4 denotes a wind guide tube attached to the upper part of the cab 1 in the longitudinal direction of the truck. As shown in Figure 3, the cab 1 expands laterally, and the exhaust port 4b on the downstream side
is a flow path that gradually narrows from the intake port 4a.

The wind guide tube 4 is formed into a curved shape as shown in FIG. The exhaust port 4 is designed to act as a kind of wind deflector to prevent the wind from colliding with the vehicle speed.
The structure is such that the b side is sequentially inclined upward.

On the other hand, the tail pipe 2 connected to the muffler 6 attached to the body frame 5 is erected close to the rear of the cab 1 as in the past, and its tail end 2a is connected to the guide as shown in FIG. It penetrates inside the wind tube 4, and the tail end port 2b is directed toward the downstream side of the vehicle speed wind, that is, the exhaust port 4b of the wind guide tube 4.

Since this embodiment is configured in this manner, the vehicle speed wind that collides with the cab 1 is captured from the air intake port 4a of the wind guide tube 4 and passes through the tail end 2a of the tail pipe 2, as shown in FIG. It is ejected from the exhaust port 4b to the rear of the truck, but it is ejected from the intake port 4a to the exhaust port 4.
Since the flow path of the wind guide tube 4 is narrowed over the distance b, the vehicle speed wind passing through the wind guide tube 4 is ejected into the atmosphere from the exhaust port 4b at a high flow velocity. Then, the exhaust gas ejected from the tail end port 2b of the tail pipe 2 is transferred to the wind guide tube 4.
Due to the pressure difference between the inside of the tail pipe 2 and the inside of the tail pipe 2, the wind guide tube 4
The tailpipe 2 is strongly sucked in by the vehicle speed wind passing through the tailpipe 2.

Further, the wind guide tube 4 functions as a wind deflector, and this wind guide tube 4 prevents the vehicle speed wind from colliding with the loading platform 3.

Therefore, according to this embodiment, compared to the conventional structure shown in FIG. 4, the exhaust gas is sucked in more strongly by the vehicle speed wind. Therefore, the exhaust pressure can be reduced more reliably and strongly than in the conventional example, and the exhaust performance can be dramatically improved. In addition, the wind guide tube 4 functions as a wind deflector,
Since the wind guide tube 4 prevents the vehicle speed wind from colliding with the loading platform 3, the running performance of the freight vehicle can be improved.

In the above embodiment, the wind guide tube 4 is configured to function as a kind of wind deflector to prevent vehicle speed wind from colliding with the loading platform 3, but the present invention is not limited to such a structure. Alternatively, a conventional wind deflector may be used to form the wind guide tube 4 within the wind deflector or below the wind deflector.

(g) Effects of the invention As described above, according to the exhaust system for a freight vehicle according to the invention, in order to reliably capture the vehicle speed wind by the wind guide tube and send the vehicle speed wind to the tail end of the tail pipe, the fourth Compared to the conventional system shown in the figure, exhaust pressure can be reduced more reliably and strongly, and exhaust performance can be dramatically improved.

In addition, the wind guide tube functions as a wind deflector and prevents the vehicle speed wind from colliding with the loading platform, making it possible to improve the running performance of the freight vehicle. .

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the exhaust system for a freight vehicle according to the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, and Fig. 3 is a plan view showing an embodiment of the wind guide tube. 4
The figure is a side view showing a conventional example. 1... Cab, 2... Tail pipe, 4... Wind guide tube.

Claims (1)

[Scope of utility model registration request] In an exhaust system for a freight vehicle, in which the tail pipe of the installed internal combustion engine is erected close to the rear of the cab, a flat exhaust port is installed at the top of the cab, with an intake opening expanding in the lateral direction of the vehicle and an exhaust opening narrowing. A wind guide tube shaped like the shape of a vehicle is installed in the front-rear direction of the vehicle, and the exhaust port side of the tube is sequentially inclined upward, and the tail pipe is passed through the tube, and the tail end of the tail pipe is connected to the exhaust port. A freight vehicle exhaust system characterized by facing toward the side.