GB2391202A

GB2391202A - Attitude controlling adjustable duct device for vehicles

Info

Publication number: GB2391202A
Application number: GB0217208A
Authority: GB
Inventors: Siamak Emami-Esfahani
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-24
Filing date: 2002-07-24
Publication date: 2004-02-04
Anticipated expiration: 2022-07-24
Also published as: GB2391202B; GB0217208D0

Abstract

A vehicle attitude controlling device comprises a pair of elongate ducts 1A,1B having a common wall comprising movable sections 5D,5E at opposite duct ends, and is suitable to be fitted to the underside of a vehicle, with one duct 1A lying above the other 1B. Controlled upwards and downwards wall movement varies the constriction of air forced through the ducts 1A,1B by vehicle motion. A resultant lift or down force can assist in maintaining a horizontal position under braking or accelerating. Under braking, a rear wall section 5E may be lowered to produce a rear down force D and a front section 5D raised to produce front end lift L. The sections 5D,5E may be moved by motors or hydraulically. A microprocessor may be programmed to control wall movement in response to sensed loads on front and rear axles of the vehicle. The ducts 1A,1B may comprise baffles B defining internal chambers C1,C2 and the air may be heated by an exhaust pipe to increase forward thrust.

Description

239 1 202

VEHICLE A11ITUDE-CONTROLLING DEVICE AND VEHICLE

FITTED THEREWITH.

The invention relates to an attitude-controlling device for a powered vehicle and a vehicle fitted with such a device.

The invention is particularly effective for vehicles which travel at high speed, more particularly, though not exclusively, motor racing cars and sports cars. It is known to provide groundffect devices which utilise the airflow around a car at speed to generate a downward force to aid adhesion to the road. Bernouilli's Equations express the relationship between the pressure generated in a flowing fluid in relation to the velocity of flow of the fluid. When the velocity is increased the pressure falls and vice versa. This is well known, its principal application being in the wings of aircraft which in flight provide a longer path for air travelling over the top surface of the wing than that passing beneath. Provided the flow is not separated or spoiled the pressure above the wing is lower, generating lift.

Under braking, especially heavy braking, of the kind experienced in motor racing, a motor vehicle is forced down at the front and rises at the back as a result of the braking forces and its momentum. Under rapid acceleration the reverse happens, the front of the vehicle rises and the rear is pushed downwards. At constant speed the vehicle generally remains horizontal but even downward force to attain added grip of the lyres to the road is an advantage.

The invention has as one of its aims the provision of a means for modifying the attitude of a vehicle especially but not exclusively under braking or acceleration in order to try to maintain the vehicle in a horizontal stable position.

( The invention provides in one aspect an attitude-controlling device for fitting to the underside of a motor vehicle comprising a pair of elongate ducts one mounted above the other with a common wall between them to receive, in use, air forced into the ducts by the vehicle's motion, the wall having front and rear sections which are each movable upward, to constrict an air flow in the upper duct and expand air flow in the lower duct, and moveable downwards, to constrict air flow in the lower duct and expand air in the upper duct, and control means operable to move said sections independently to generate positive lift or negative lift (downforce) at the front andlor i rear of the vehicle to assist in maintaining the horizontal attitude of the vehicle when in motion.

The invention provides in another aspect a motor car having fitted to the underside thereof an attitude-controlling device comprising a pair of ducts one mounted above the other with a common wall between them to receive in use air forced into the ducts by the vehicle's motion, the wall having front and rear sections which are each movable upward to constrict an air flow in the upper duct and expand air flow in the lower duct, and moveable downwards to constrict air flow in the lower duct and expand air in the upper duct, and control means operable to move said sections independently to generate positive lift or negative lift (downforce) at the E front and/or rear of the vehicle to assist in maintaining the horizontal attitude of the vehicle when in motion.

The said front and rear sections are preferably disposed so as to be positioned at or near the front and rear axles of the vehicle respectively.

The control means preferably comprises sensors to detect downforces and up forces at the front and rear axles of the motor vehicle, and a microprocessor programmed to control said moveable sections to generate lift when a downforce is detected at a particular axle and negative lift when an upward force is detected at a particular axle.

In a simple form the control means may be linked to the brake and accelerator controls of the vehicle and arranged such that when the vehicle is under heavy braking the control means operates to raise the front moveable section and lower the rear moveable section, creating lift at the front and downforce at the back; and under acceleration, to raise the rear moveable section and lower the front moveable section creating lift at the back and downforce at the front.

It may be that under certain conditions of the vehicle either the front or rear moveable section will be moved whilst the other may be held in a neutral position, or both will be moved down together, for example under substantially constant speed conditions. The sensors may be linked to the suspension elements of the vehicle's front and rear axles or wheels to sense the downward or upward movement and control the moveable sections accordingly.

The front and rear sections are preferably moved by electric motors but may be moved hydraulically, including by pneumatic pressure.

Advantageously the air flow leaving the device is preferably heated by the engine exhaust pipe of the motor car to give additional forward thrust to the motor car.

( An embodiment of the invention will now be described by way of example only and with reference the accompanying drawings, in which Fig. I is a schematic longitudinal sectional view of a device according to the invention fitted to a racing car, in a neutral position, Fig.2 is a schematic longitudinal sectional view of the device of Fig. 1 fitted to a racing car, the device being shown as disposed when the car is under braking, Fig.3 is a schematic longitudinal sectional view of the device of Fig. 1 fitted to a racing car, this device being shown as disposed when the car is under acceleration, and Fig.4 is a schematic longitudinal sectional view of the device of Fig. 1 fitted to a racing car, the device being shown as disposed when the car is at substantially constant speed.

The device as shown in the figures comprises a pair of upper and lower ducts shown generally I A and I B respectively disposed one above the other along the centre line of a motor racing car M (shown in part only) beneath the floor thereof.

The ducts have a series of baffles B to maintain a smooth non- turbulent air flow in the ducts. The baffles define two chambers C 1, and C2 near the front and rear axles of the motor racing car, and divided by a wall shown generally as 3 which is arranged in sections, some of which are moveable to deflect the flow of air passing through the ducts as a result of forward movement of the car. The sections comprise three fixed sections 5A, 5B and 5C, vertically displaceable sections SD and 5E and

s four link sections 5F, 5G, 5H and 5J. Each of the link sections links one of the fixed sections to a vertically displaceable section. Air leaving the device is preferably heated by the or an exhaust pipe 5 of the motor car engine (not shown).

In Fig. 1 the wall 3 is disposed in a straight line so that the air flows are substantially un-deviated. In this position the device has no significant effect on the attitude of the vehicle.

In Fig.2 the vertically displaceable baffle SD nearest the front of the motor racing car is displaced upwardly and the baffle 5E to the rear of the motor racing car is displaced downwardly by electro mechanical actuators (not shown). This has the effect of constricting airflow At (and thus increasing air flow velocity) in the upper duct of chamber C I and expanding airflow A2 in chamber C2. By Bernouillis Law this results in a pressure drop above 5D and below 5E resulting in lift L near the front axle and downforce D near the rear axle.

In Fig.3 the vertically displaceable baffle SD nearest the front of the motor racing car is displaced downwardly and the baffle 5E to the rear of the motor racing car is displaced upwardly be electro mechanical actuators (not shown). This has the effect of expanding airflow Al (and thus decreasing air flow velocity) in the upper duct of chamber C1 and vice versa in chamber C2. By Bernouilli's Law this results in a pressure drop below 5D and above 5E resulting in lift L near the rear axle and downforce D the front axle.

In Fig. 4 the vertically displaceable baffles SD and 5E are both displaced downwardly. This has the effect of constructing airflow A2 in both chambers C I and C2 so increasing air flow velocity resulting in a downforce D at both the front and

rear axles. This configuration is most appropriate when the vehicle is travelling at more or less constant velocity without any large acceleration or deceleration.

Various modifications will be readily apparent to those skilled in the art, without departing from the ambiet of the invention.

The ducts are preferably substantially plain box section linear tubes.

Claims

( CLAIMS

An attitude-controlling device for fitting to the underside of a motor vehicle comprising a pair of elongate ducts one mounted above the other with a common wall between them to receive, in use, air forced into the ducts by the vehicle's motion, the wall having front and rear sections which are each movable upward, to constrict an air flow in the upper duct and expand air flow in the lower duct, and moveable downwards, to constrict air flow in the lower duct and expand air in the upper duct, and control means operable in use to move said sections independently to generate positive lid or negative lid (downforce) at the front and/or rear of the vehicle to assist in maintaining the horizontal attitude of the vehicle when in motion, relation to the road surface.
2. An attitude-controlling device as claimed in claim 1 in which said front and rear sections are preferably disposed so as to be positioned at or near the front and rear axles of the vehicle respectively.
3. An attitude-controlling device as claimed in claim 1 or claim 2 in which the control means comprises sensors to detect downforces and up forces at the front and rear axles of the motor vehicle, and a microprocessor programmed to control said moveable sections to generate lift when a downforce is detected at a particular axle and negative lift when an upward force is detected at a particular axle.
4. An attitude-controlling device as claimed in any preceding claim in which the control means is linked to the brake and accelerator controls of the vehicle and arranged such that when the vehicle is under heavy braking the control means

( operates to raise the front moveable section and lower the rear moveable section, creating lift at the front and downforce at the back; and under acceleration, to raise the rear moveable section and lower the front moveable section creating lift at the back and downforce at the front. 3
5. An attitude-controlling device as claimed in any of claims 1- 3 in which the sensors are linked to the suspension elements of the vehicles front and rear axles or wheels to sense the downward movement and control the moveable sections accordingly, to maintain the horizontal attitude of the vehicle.
6. An attitude-controlling device as claimed in any of claims 1-5 in which the 3 front and rear sections are moved by electric motors.
7. An attitude-controlling device as claimed in any of claims 1-5 in which the front and rear sections are moved hydraulically.
8. An attitude-controlling device as claimed in any preceding claim arranged such that the air flow leaving the device is heated by the engine exhaust pipe of the vehicle to give additional forward thrust to the vehicle.
9. A motor car having fitted to the underside thereof an attitudecontrolling device comprising a pair of ducts one mounted above the other with a common wall between them to receive in use air forced into the ducts by the vehicle motion, the wall having front and rear sections which are each moveable upward to constrict an air flow in the upper duct and expand air flow in the lower duct, and moveable downwards to constrict air flow in the lower duct and expand air in the upper duct, and control means operable to move said sections independently to generate positive

lift or negative lift (downforce) at the front and/or rear of the vehicle when in motion, relative to the road surface.
10. A motor car as claimed in claim 9 in which said front and rear sections are preferably disposed so as to be positioned at or near the front and rear axles of the vehicle respectively.
11. A motor vehicle as claimed in claim 9 or claim 10 in which the control means comprises sensors to detect downforces and up forces at the front and rear axles of the motor vehicle, and a microprocessor programmed to control said moveable sections to generate lift when a downforce is detected at a particular axle and negative lift when an upward force is detected at a particular axle.
12. A motor vehicle as claimed in any of classes 9, 10 or 11 in which the control means is linked to the brake and accelerator controls of the vehicle and arranged such that when the vehicle is under braking the control means operates to raise the front moveable section and lower the rear moveable section, creating at the front and downforce at the back; and under acceleration, to raise the rear moveable section and lower the front moveable section creating lift at the back and downforce at the front.!
1 3. A motor vehicle as claimed in any claims 9, 10, 1 1 or 12 which the sensors are linked to the suspension element of the vehicles front and rear axles or wheels to sense the downward movement and control the moveable sections accordingly, to maintain the horizontal attitude of the vehicle.
14. A motor vehicle as claimed in any of claims 9, 10, 11, 12 or 13 in which the front and rear sections are moved by electric motors.
lO ( I S. A motor vehicle as claimed in any of claims 9, 1O, 11, 12, 13, or 14 in which the front and rear are moved hydraulically.
16. A motor vehicle as claimed in any of claims 9,10, 11, 12, 13,14 or 15 arranged such that air flow leaving the device is heated by the engine exhaust pipe of the vehicle to give additional forward thrust to the vehicle.
17. An attitude-controlling device substantially as hereinbefore described with reference to and/or as shown in the accompanying drawings.
18. A motor vehicle having an attitude-controlling devices substantially as hereinbefore described with reference to and/or as shown in the accompanying drawings.