GB2164302A

GB2164302A - Air intake duct for a load-carrying vehicle equipped with a driver's cab

Info

Publication number: GB2164302A
Application number: GB08521838A
Authority: GB
Inventors: Staffan S Sjostrom; Stig Lennart Dahlen; Roland B Lundman
Original assignee: Saab Scania AB
Current assignee: Saab AB
Priority date: 1984-09-07
Filing date: 1985-09-03
Publication date: 1986-03-19
Also published as: GB8521838D0; SE8404492D0; SE439751B; DE3531468A1; DE3531468C2; GB2164302B

Abstract

The driving engine of the vehicle is supplied with combustion air from a vertical air intake duct (4) constituting a unit mountably applied to one side wall (5) of the cab (2), and forward of a transverse plane through the cab rear wall (18). The duct (4) is formed as a vertically extending aerodynamic baffle, defined laterally to the vehicle by an exterior wall (6), which has its forward edge (7) in juxtaposition with the cab side wall (5), and rearwardly has a successively increasing distance to the side wall (5). An air inlet opening is arranged in the duct (4) and the lower portion of the duct (4) is adapted for connection to the engine air intake system. <IMAGE>

Description

SPECIFICATION Air intake duct for a load-carrying vehicle equipped with a driver's cab The present invention relates to an air intake duct for a load-carrying vehicle equipped with a driver's cab, said duct being intended to take air to a driving engine arranged under the cab.

It is known in cab-over-engine trucks to arrange the vehicle driving engine under the cab. The engine is then usually supplied with combustion air via-a vertical intake pipe arranged behind the cab, the inlet itself being arranged above the cab roof.

Since the air inlet is ata relatively large height from the ground, the presence of dust particles and suchlike heavier particles of dirt is less there than at levels closer to the ground. This results in an increase in air filter life.

A disadvantage in placing the air intake pipe behind the cab is that the pipe requires a certain amount of space. For trucks provided with a superstructure behind the cab, e.g. a closed body or platform, the placing of the intake pipe results in that the superstructure must be made shorter, reducing the vehicle carrying capacity to a corresponding extent. Furthermore, if the cab is equipped with a sleeping compartment behind the driver's seat, this means that the cab must be longer than usual, which further reduces the loading space of the vehicle.

Apart from the reduction of the available loading space mentioned above, there is a further disadvantage in placing the intake pipe behind the cab, and this is that space required for the pipe between cab and super structure is to a major extent just an empty air space. This acts negatively on the vehicle air resistance, since it gives rise to an unfavourable vortex formation in the air space.

The present invention has the object of eliminating the drawbacks mentioned above, and relates to an air intake duct for taking air to a driving engine mounted under the driver's cab of a load-carrying vehicle. In such a case the invention is characterized in that: the air intake duct constitutes a unit mountably applied to at least one side wall of the cab, substantially forward of a transverse plane through the rear wall of the cab; the duct is formed as an aerodynamic baffle having vertical extension, the duct being defined laterally to the vehicle by an exterior wall having its forward edge in juxtaposition with the cab side wall and having rearwardly a successively increasing distance to the side wall; an air inlet opening is arranged in the air intake duct; and the lower portion of the air intake duct is adapted for connection to the engine air intake system.

By inventively arranging the air inlet at the side of the cab, the space between cab and superstructure may be fully utilised for the vehicle loading space.

The inventive implementation of the duct results in that its exterior may act as an air baffle, thus achieving a uniform air flow along the vehicle when it is in motion, and this contributes to lowering the drag.

Further properties will be understood from the following description of an embodiment exemplifying the invention. The description is made with reference to the accompanying drawings, on which Figure 1 is a side elevation of a truck equipped with an inventive air intake duct, Figure 2 is a side elevation of the duct in Figure 1, to an enlarged scale.

Figure 3 is a rear elevation of the duct in Figure 2, and Figure 4 is a horizontal cross-section A-A of the duct in Figure 2, to an enlarged scale.

A load carrying vehicle 1, in the form of a truck is illustrated in Figure 1, and is equipped with a driver's cab 2, and behind the cab a closed body superstructure 3. The vehicle 1 is of the cab-overengine type, which means that the unillustrated driving engine of the vehicle is arranged substantially under the cab 2. The engine is supplied with combustion air via en inventive air intake duct 4, arranged at one side wall 5 of the cab 2, and with substantially vertical extension.

The duct includes a vertically extending exterior wall 6, with its forward edge 7 in juxtaposition with the cab side wall 5. The exterior wall 6 is slightly convex, and rearwards from its forward edge its distance to the cab side wall 5 successively increases. At its trailing edge 8 the exterior wall 6 is in juxtaposition with the superstructure 3, which has a width somewhat exceeding that of the cab 2.

The duct also includes an inner wall 9 and a rear wall 10 made integrally and attached to the exterior wall 6 by a glued joint. The inner wall 9 is substantially flat, and accompanies the contour of the cab side wall 5. A plurality of attachment brackets 12 are attached to the forward and rear ends of the inner wall 9 by bolted joints 11. An upper and a lower fastening 14 and 15 are attached to the cab side wall 5, and to them are attached the brackets 12 with the aid of vertical bolted joints 16. There is an elastic dampening element 17, preferably of rubber material, mounted between each attachment bracket and the respective fastening 14, 15 and passed through by the bolt 16.

The air intake duct is fastened to the cab side wall 5 such that the rear wall 10 of the duct is situated substantially in front of a transverse plane passing through the cab rear wall 12.

In a joined condition the walls 6, 9, 10 form the air intake duct 4 for taking combustion air to the engine. At its upper end the duct is terminated by a cover 25, which is glued at the edges to the respective walls. The exterior wall 6 has its upper portion formed with an air inlet opening 20, which is covered by a grating 21, fastened round the opening 20 by a bolted joint.

The duct 4 is preferably manufactured from glass fibre-reinforced plastics material, which allows the walls 6, 9, 10 readily to be given a suitable shape.

The lower end portions of the walls 6,9,10 merge into a pipe stub 22, to which is fastened an elastic bellows 24 by a conventional hose clip 23. The beilows 24 is part of the engine air intake system, which takes air to the engine via an unillustrated air filter.

The duct 4 is configurated so that there is a smooth junction between the cab 2 and superstructure 3, which is advantageous from the aerodynamic aspect. It is suitable to utilise only one duct 4 for engines with a simple air intake system, this inventively implemented duct being fastened to a side wall 5 of the cab 2. The other side wall of the cab may then be advantageously equipped with a baffle formed in agreement with the duct exterior wall 6. The aerodynamic conditions for the vehicle 1 are thus further improved, while the vehicle is given a more symmetric appearance.

With vehicles having dual air intake systems, this being usual for V engines, both side walls of the cab are equipped with inventively embodied air intake ducts.

Within the scope of the following claims the invention may be modified and implemented differently from what has been exemplified above.

Claims

1. Air intake duct for a load-carrying vehicle equipped with a driver's cab, said duct being intended to take air to a driving engine arranged under the cab, characterized in that the duct 4 constitutes a unit mountably applied to at least one side wall of the cab, substantially forward of a transverse plane through the rear wall of the cab; the duct is formed as an aerodynamic baffle having vertical extension, the duct being defined laterally to the vehicle by an exterior wall having its forward edge in juxtaposition with the cab side wall and rearwardly having a successively increasing distance to the side wall; an air inlet opening is arranged in the duct, and the lower portion of the duct is adapted for connection to the engine air intake system.

2. Duct as claimed in claim 1, characterized in that the trailing edge of the exterior wall is adapted to be in juxtaposition with the outer portion of a superstructure arranged behind the cab.

3. Duct as claimed in claim 1, characterized in that the air inlet opening is arranged in the exterior wall.

4. Duct as claimed in claim 3, characterized in that in a horizontal cross-section the exterior wall is curved.

5. Duct substantially as hereinbefore described with reference to and as shown in the accompanying drawings.