JPH0322324B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an intake system for an engine in a cabover type vehicle.

The intake device that supplies air into the combustion chamber of the engine is installed in various positions depending on the vehicle model, but in cab-over type vehicles, it is usually installed in the first position.
As shown in the figure, this air intake device 3 is provided in a space between a cab 1 and a loading platform 2. In this case, the intake pipe 4 of the intake device 3 is erected in a chimney-like manner in the space for the cab/cargo bed, and a dust cover 5 is attached to the upper part of the intake pipe 4. As is clear from FIG. 2, the dust cover 5 covers the upper part of the suction port 6 opened at the upper end of the intake pipe 4, and prevents rainwater, dirt, dust, etc. from entering from the suction port 6. . The dust cover 5 is attached to the intake pipe 4 by the stay 7.
The outside air is taken in through the opening 8 on the lower side of the cover 5, and the air that flows into the dust cover 5 flows into the pipe from the suction port 6 of the intake pipe 4 (the direction of air flow is shown in Fig. 1 and (This is the opposite direction of the arrow shown in Figure 2).

According to the above-mentioned intake device 3, it is possible to suppress the inconvenience of rainwater, dirt, dust, etc. being sucked in, and also to suppress the sucking of hot air emanating from the engine, thereby reducing the intake air filling density into the combustion chamber (not shown) of the engine. can be prevented. However, as a result of recent studies, it has become clear that this type of conventional intake system causes so-called muffled noise inside the cab 1. The causes are generally considered to be as follows.

The flow rate of air flowing in from the intake section, that is, the opening 8 and the suction port 6, is not always constant, but usually fluctuates at a predetermined period corresponding to the operation of the engine piston (not shown). . For this reason, a slight pulsating sound is generated in the intake section during intake. This sound emanates downward through the suction port 6 and the opening 8 as indicated by the arrows in FIGS. 1 and 2. However, since the intake device 3 is located between the rear wall (back panel or rear glass) 1a of the cab 1 and the front end wall 2a of the loading platform 2, the pulsating sound emitted as described above causes cavity resonance. A phenomenon occurs, which appears as a loud muffled sound inside the cab 1.

The present invention has been made based on the above-mentioned novel recognition, and its purpose is to provide an air intake device that can suppress the generation of muffled noise more than ever before.

Embodiments of the present invention will be described below with reference to the drawings.

The intake device 3 according to the present invention shown in FIG. 3 is also arranged between the cab 1 and the loading platform 2 behind it,
It has an intake pipe 4 that stands upright in a substantially vertical direction, and a dust cover 5 that is provided above the intake pipe 4. This dust cover 5 has an opening 8 facing outward in the lateral direction of the vehicle, as also shown in FIG.
All other parts are closed, and the bottom wall 5a
An intake pipe 4 is fixed to the intake pipe 4. Further, the suction port 6 of the suction pipe 4, which is located at the upper part of the suction pipe 4 and opens inside the dust cover 5, opens in the opposite direction to the opening 8.

The outside air is taken in through the opening 8 of the dust cover 5 and the suction port 6 of the intake pipe 4, and this itself is not particularly different from a conventional intake device. However, in the configuration according to the present invention, since the opening 8 of the dust cover 5 faces outward in the lateral direction of the vehicle, the pulsating noise generated during intake is directed to the lateral side of the vehicle, as shown by the arrows in FIGS. 3 and 4. Diverging outward in the direction,
This is prevented or suppressed from entering the gap between the cab 1 and the loading platform 2. Therefore, the resonance phenomenon between the cab and the loading platform is suppressed, and the inconvenience of muffled noise inside the cab 1 is reduced.

Furthermore, since the suction port 6 of the intake pipe 4 is located in the opposite direction to the direction of the opening 8 of the dust cover 5, the pulsating noise generated at the suction port 6 can be suppressed from emanating from the opening 8. Rainwater, dirt, dust, etc. that enter through the opening 8 are removed from the suction port 6.
It can also prevent the inconvenience of direct intrusion.

According to the present invention, the opening of the dust cover is also oriented outward in the lateral direction of the vehicle, and the inlet of the intake pipe is arranged in the opposite direction to the direction of the opening of the dust cover. The generation of muffled noise can be suppressed, and the pulsating noise generated at the intake port of the intake pipe can be suppressed from emanating from the opening of the dust cover. It also prevents problems such as rainwater, dirt, dust, etc. from entering through the intake port of the intake pipe.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view of a cab-over type vehicle having a conventional intake system, FIG. 2 is a perspective view showing details of the intake system shown in FIG. 1, and FIG. 3 has an intake system according to the present invention. FIG. 4 is a partial perspective view of the cab-over type vehicle, and is a perspective view showing details of the intake system shown in FIG. 3. 1... Cab, 2... Loading platform, 3... Intake device,
4...Intake pipe, 5...Dust cover, 6...Suction port, 8...Opening.

Claims (1)

[Scope of Claims] 1. An air intake pipe that stands upright between the cab and the loading platform in the shape of a chimney, and a dust cover provided at the top of the air intake pipe, and includes an opening of the dust cover and an opening of the dust cover. In an engine intake system for a cab-over type vehicle in which air is taken in through an intake port of an intake pipe that opens inside, the opening of the dust cover is disposed toward the outside in the lateral direction of the vehicle, and the intake port of the intake pipe is . The air intake device, wherein the air intake device is arranged facing in a direction opposite to the direction of the opening of the dust cover.