GB2365064A

GB2365064A - Motor vehicle engine air intake duct for preventing intake of water when driving through floods

Info

Publication number: GB2365064A
Application number: GB0017700A
Authority: GB
Inventors: Steen Mccollin
Original assignee: Land Rover Group Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2000-07-20
Filing date: 2000-07-20
Publication date: 2002-02-13
Anticipated expiration: 2020-07-20
Also published as: GB2365064B; GB0017700D0

Abstract

The air intake duct 16 includes a diverter valve assembly 25 having a generally rectangular housing 31 with a drain outlet 34 upstream of an auxiliary air inlet 37. A flap 36 is pivotally mounted on a spindle 41 which is spring biassed to close the drain outlet 34 and the auxiliary air inlet 37. The flap 36 has a spoiler portion 44 which will be impinged upon by any water drawn into the duct 16 if the vehicle encounters a flood to cause the flap 36 to pivot against the spring bias and move it to the diverter position, fig.5, so that water can exit through the drain outlet 34. The flap 36 then blocks the duct 16 between the drain outlet 34 and the auxiliary air inlet 37 so that no water can be drawn into the engine, the auxiliary inlet 37 being open so that the engine can continue to run normally. Upon leaving the flood, the flap 36 can spring back to the normal, fig.4, position. In a modification (fig.6), an actuator is connected to a controller which in turn is connected to a sensor which can detect the presence of water and act through the controller 52 to open the drain outlet 34 and the auxiliary air inlet 37 and close the duct between these two. The sensor 53 is preferably an infra-red device which is relatively unaffected by dirt.

Description

<Desc/Clms Page number 1> Air Intake Duct This invention relates to air intake ducts for internal combustion engines on motor vehicles. Such ducts are provided usually to duct cold air from a front region of the vehicle to an air filter and thence the engine. A problem with such ducts is that it is not uncommon for fords or floods to be encountered, particularly where such vehicles are intended for off-road use. Unfortunately, a vehicle which travels through a ford or flood at any appreciable speed tends to create a bow-wave at the front which is usually in the region of the main air inlet for the duct. If water is taken from there into the engine then this can have disastrous results. Since water is incompressible the engine can be brought to an abrupt halt by water in one of the combustion chambers and- mechanical damage is inevitable. Various attempts have been made to avoid the problem of water ingestion. Since water ingestion involves preventing the inflow of water and the provision of an alternative intake for the supply of air, such earlier attempts have tended to address each of these problems on a piecemeal basis. The present invention aims to provide a simpler solution to the problem of preventing water ingress and providing an alternative air intake. In accordance with one aspect of the invention there is provided an air intake duct for an internal combustion engine in a motor vehicle, the duct including a am inlet for the entry of air into the duct, a main outlet for the transfer of air from the duct to the engine, an auxiliary inlet for the entry of air into the duct downstream of the main inlet, a drain outlet upstream of the auxiliary inlet and a diverter valve having a valve member movable between a first, normal, position in which the valve member covers both the auxiliary inlet and the drain outlet and a second, diverter, position in which the auxiliary inlet and the drain outlet are

uncovered and the valve member blocks the duct between the drain outlet and the auxiliary inlet.

The valve member may comprise a pivoted flap having a first flap portion on one side of a pivot axis for covering the drain outlet and a second flap portion on the other side of the pivot axis for covering the auxiliary inlet, one of said flap portions being arranged to block the duct between the drain outlet and the auxiliary inlet when the drain outlet and the auxiliary inlet are uncovered.

The duct may be curved immediately upstream of the drain outlet, the drain outlet being on the outside of the curve so that water entering the duct through the main inlet is centrifuged towards the drain outlet.

In one arrangement, the valve member is spring loaded into the normal position and includes a spoiler portion which in use is acted on by water flowing from the main inlet towards the drain to move the valve member into the diverter position. The spoiler portion may comprise an extension of the second flap portion and may be curved inwardly into the duct when the valve member is in the first position.

In another arrangement, the valve member is movable by an actuator from one of said positions to the other, the actuator being operable by control means coupled to water sensor means in the duct between the main inlet and the drain outlet. The sensor means may be on the outside of the curve or immediately downstream thereof where it will be covered by water centrifuged to the outside of the curve.

In accordance with another aspect of the invention there is provided a motor vehicle having an internal combustion engine and an air intake duct according to said one aspect of the invention.

The invention will now be described by way of example and with reference to the accompanying drawings, of which:- Fig. 1 is a side elevation of an engine compartment of a motor vehicle showing an internal combustion engine and an air intake duct according to the invention; Fig. 2 is a view on arrow A of Fig. 1 showing the duct and a radiator; Fig.3 is a plan view on arrow B of the engine and air intake duct shown in Fig. 1; Fig. 4 is a cross-section through part of the air intake duct shown in Figs. 1 to 3 showing a diverter valve having a valve member in a first, normal, position; Fig.5 is a view similar to Fig.4 showing the diverter valve member in a second, diverter, position; and Fig.6 is a view based on part of Fig.1 showing an alternative.

Referring to Figs.1 to 5, a motor vehicle 11 includes an engine compartment 12 which houses an internal combustion engine 13 having an intake manifold 14 supplied with air through an air filter assembly 15 which is fed by an air intake duct 16 having two rectangular inlets 17, 18 positioned above a forward facing engine cooling system radiator 19. The inlets 17, 18 are protected by the leading edge of the engine compartment bonnet or hood 21 and together form an inlet for the entry of air into the duct 16 where they connect to an upper transverse duct portion 22 which in turn connects to a vertical duct portion 23 through a curved duct portion 24.

Between the curved duct portion 24 and the vertical duct portion 23 there is a diverter valve assembly 25 which will be described in more detail with reference to

Figs.4 and 5. The vertical duct portion 23 connects to the air filter assembly 15 through another curved duct portion 26, a longitudinal horizontal duct portion 27 and a final curved duct portion 28 which provides a duct outlet where the duct connects to the air filter assembly.

The diverter valve assembly 25 includes a housing 31 which forms part of the air intake duct 16. The housing 31 is generally rectangular in cross-section but having round section tubular end pieces 32 and 33 to connect to the curved duct portion 24 and the vertical duct portion 23. A drain outlet 34 is formed in one side wall of the housing 31 immediately downstream of the outside of the curved duct portion 24 and this is normally covered by a first flap portion 35 of a valve member in the form of a flap 36 which is pivotally supported by a spindle 41 which can rotate in the housing 31.

Immediately downstream of the drain outlet 34 is an auxiliary air inlet 37 which is normally covered by a second flap portion 38 of the pivoted flap 36, the second flap portion being on the other side of the pivot axis of the spindle 41 to the first flap portion 35. The spindle 41 carries an arm 42 connected to a tension spring 43 to bias the flap 36 into closure of the drain outlet 34 and the auxiliary air inlet 37. The flap 36 includes a spoiler portion 44 which is formed as an extension of the first flap portion 35 and there is a correspondingly shaped step 45 in the inner wall of the housing 31 so that when the flap 36 is pivoted into the diverter position as shown in Fig.5 it can abut the step 45. In this position the drain outlet 34 and the auxiliary inlet 37 are both uncovered.

In normal use of the vehicle, the auxiliary air inlet 37 and the drain outlet 34 are covered by the flap 36 and the engine 13 draws in air from the inlet manifold 14 through the inlet filter 15, the duct 16 and the inlets 17 and 18. If the vehicle encounters a flood or a ford then, depending upon the speed of the vehicle, a bow

wave will build up in front of a vehicle and water is liable to enter the front inlets 17 and 18. If this happens, the water gets swept into the transverse duct portion 22 but will centrifuge to the outside of the curved duct portion 24 after which it will encounter the spoiler portion 44 of the flap. Water which impinges the spoiler portion 44 will cause the flap 36 to pivot against the spring bias of the tension spring 43 to move it to the diverter (Fig.5) position so that water can exit through the drain outlet 34. The first flap portion 35 blocks the duct 16 between the drain outlet 34 and the auxiliary inlet 37 so that no water can be drawn into the inlet manifold 14. The auxiliary inlet 37 is now open so that the engine can continue to run normally. Upon leaving the flood or ford when there is no water impinging upon the flap 36, the spring can move the flap back to the normal position as shown in Fig.4.

It will be appreciated that the action of the diverter valve 25 is entirely automatic and whilst it depends on the in-rush of water for its operation this water is diverted well away from the auxiliary inlet. With careful attention to the design details, the air pressures on either side of the flap 36 can be balanced so that there is little or no tendency for the valve to be influenced by air flow into the engine. By using a single flap valve member 36 to open the drain outlet 34 and the auxiliary air inlet 37 and to close the duct between the drain outlet 34 and the auxiliary air inlet 37, air flow into the engine is un-interrupted.

If required, an auxiliary air inlet duct can be connected to the auxiliary air inlet 37 to draw air from an appropriately dry area of the engine compartment 12. Similarly, a drain duct can be connected to the drain outlet 34 to allow water to drain to an appropriate region where it will least affect components situated in the engine compartment 12.

In the modification shown in Fig.6 the tension spring 43 is replaced by an actuator 51 (e.g. a solenoid) and this is connected to a controller 52 which in turn is connected to a sensor 53 in the wall of the curved duct portion 34. The sensor 53 is preferably on the outside of the curve or immediately downstream of it so that it will be covered by water centrifuging to the outside when it can detect the presence of water in the duct 16 and act through the controller 52 to open the drain outlet 34 and the auxiliary air inlet 37 and close the duct between these two. The sensor 53 is preferably an infra-red device which is relatively unaffected by dirt.

In a further modification (not shown), the Rap 36 is spring loaded into the diverter position and is held in the normal, shut position by a spring-loaded latch which is released by the actuator 51. A second actuator may be provided so as to be acted on through the controller 52 when water is no longer detected to move the flap back to the normal position with the drain outlet 34 and the auxiliary air inlet 37 closed.

Claims

CLAIMS 1. An air intake duct for an internal combustion engine in a motor vehicle, the duct including a main inlet for the entry of air into the duct, a main outlet for the transfer of air from the duct to the engine, an auxiliary inlet for the entry of air into the duct downstream of the main inlet, a drain outlet upstream of the auxiliary inlet and a diverter valve having a valve member movable between a first, normal, position in which the valve member covers both the auxiliary inlet and the drain outlet and a second, diverter, position in which the auxiliary inlet and the drain outlet are uncovered and the valve member blocks the duct between the drain outlet and the auxiliary inlet.
2. A duct according to claim 1 wherein the valve member comprises a pivoted flap having a first flap portion on one side of a pivot axis for covering the drain outlet and a second flap portion on the other side of the pivot aids for covering the auxiliary inlet, one of said flap portions being arranged to block the duct between the drain outlet and the auxiliary inlet when the drain outlet and the auxiliary inlet are uncovered.
3. A duct according to claiml or claim 2 wherein the duct is curved immediately upstream of the drain outlet, the drain outlet being on the outside of the curve so that water entering the duct through the main inlet is centrifuged towards the drain outlet.
4. A duct according to any preceding claim wherein the valve member is spring loaded into the normal position and includes a spoiler portion which in use is acted on by water flowing from the main inlet towards the drain to move the valve member into the diverter position.

<Desc/Clms Page number 8>
5. A duct according to claim 4 when dependent upon claim 2 wherein the spoiler portion comprises an extension of the second flap portion.
6. A duct according to claim 5 wherein the spoiler portion is curved inwardly into the duct when the valve member is in the first position.
7. A duct according to any of claims 1 to 3 wherein the valve member is movable by an actuator from one of said positions to the other, the actuator being operable by control means coupled to water sensor means in the duct between the main inlet and the drain outlet.
8. A duct according to claim 7 when dependent upon claim 3 wherein the sensor means is on the outside of the curve or immediately downstream thereof.
9. A motor vehicle having an internal combustion engine and an air intake duct according to any preceding claim.
10. An air intake duct for an internal combustion engine in a motor vehicle, the duct being substantially as described herein with reference to Figs. 1 to 5 or modified as described with reference to Fig.6 of the accompanying drawings.
11. A motor vehicle having an internal combustion engine and an air intake duct substantially as described herein with reference to Figs.1 to 5 or modified as described with reference to Fig.6 of the accompanying drawings.