GB2225992A

GB2225992A - Air deflector for a car

Info

Publication number: GB2225992A
Application number: GB8829865A
Authority: GB
Inventors: Geoffrey Henry Duncan Fox
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1988-12-19
Filing date: 1988-12-19
Publication date: 1990-06-20
Also published as: GB8829865D0

Abstract

An air deflector 26 for a convertible car is fitted in an upright position behind the rearmost seats 22. The deflector is intended to deflect the air flow which would otherwise cause undesirable buffeting of the passengers. In a preferred form the deflector is lowered when the roof 14 is raised, and is automatically raised when the roof is lowered. <IMAGE>

Description

Air deflector for a car This invention relates to a car which has a fold-down roof (hereinafter referred to as a convertible roof), and to an air deflector for such a car.

It is a disadvantage of cars with convertible roofs that the desirable exposure to the open air when the roof is down is accompanied by undesirable buffeting of the passengers by air turbulence. This is particularly pronounced where the car has rear seats as well as front seats, and the rear seat passengers suffer to a greater degree than the front seat passengers.

The problem is caused by the air currents arising from the movement of the car. Figure 1 illustrates in dotted lines 10 the normal path of the air currents at the rear of the car. It will be seen that the air flow has a component which reverses at the back and starts to flow in a forward direction. This creates considerable air turbulence which leads to the undesired buffeting of the rear seat passengers. The air flow patterns which occur are clearly more complex than illustrated in the Figure, but the Figure does illustrate the root of the problem.

attempts have been made to overcome this problem by fitting an additional air deflector to the top of the roll bar 12 (see German Patent Specification 32 35 148), with the object of raising the air flow as a whole over the vehicle, but this has not been successful, probably because this deflector was mounted too low to be able to affect the air flow.

According to the present invention, there is provided a car with a convertible roof and with an air deflector mounted in a generally upright position above or immediately behind the seat back of the rearmost row of seats.

Preferably the deflector is mounted so as to form an upwardly directed extension of the seat back of the rearmost row of seats.

The deflector may be mounted so that it can be lowered from its upright position when the roof is raised. In a preferred embodiment, the deflector is spring loaded into its upright position and is latched in its lowered position. The latch may be automatically released when the hood is lowered, so that the spring-loading raises the deflector. A Bowden cable can be connected to the hood frame to pull on and to release the latch on lowering of the hood.

The deflector may have a profile such that it conforms to the shape of the seat back when it is folded down.

In order for the deflector to be effective in deflecting the air currents which cause passenger buffeting, the top of the deflector should project at least 100 mm above the datum line. The position of the datum line will vary from car to car, and is defined as the lowest transverse line at which the reverse air flow as illustrated in dotted lines in Figure 1 (taking into account the surrounding car bodywork and, if appropriate, the folded roof but not any upward extension of the seat back) intersects with the position of a passenger in a rear seat.

The seat back itself may be extended above the datum line, and where this happens, the combined height of the seat back and the deflector should extend at least 100 mm above the datum line.

The maximum height of the deflector will be determined, for each car, by the driver's sight lines using the rear view mirror. There are legal requirements which specify the distance behind the car at which the driver must be able to see the surface of the road when using the rear view mirror.

The invention also provides an air deflector for a car with a convertible roof, the deflector including a deflector plate and means for mounting the deflector plate in a generally upright position immediately behind the seat back of the rearmost row of seats.

The deflector is preferably mounted on a horizontal hinge axis so that it can be moved between an upright position and a lowered position; a spring can urge the deflector into its upright position and a latch can be provided to hold the deflector in its lowered position.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of a car with the roof lowered and the deflector raised; Figure 2 is a side view, on a larger scale, of a seatback and deflector with the deflector raised; and Figure 3 is a schematic perspective view of the deflector and the mechanism for raising and lowering it.

Figure 1 shows a car 12 with a convertible roof. In the Figure, the roof is shown lowered and folded at 14. The car has a windscreen 16, a roll bar 18, a front row of seats 20 and a rear row of seats 22.

When the car is moving, the air flow over the car is as shown by the bold line 24. 9t the rear of the car, when the roof is down, there is a tendency for the air flow to reverse and to follow the dotted line path 10 and, as already explained, this reverse flow causes discomfort to passengers in both the front and the rear seats 20 and 22.

In order to deflect this reverse flow away from the passengers, a deflector 26 is fitted.

The deflector results in the reverse flow 10 being deflected so that the air flow is redirected into a complex turbulent area, shown as a continuation of the bold line flow, from which the air ultimately flows away from the car in a rearward direction as shown at 28.

Figure 2 shows the deflector 26 pivoted on an axis 30 and mounted at the top of the rear seat back 22. The deflector can be moved from its raised position shown in bold lines to a lowered position shown in dotted lines. ks shown, the rear face is contoured so that it fits snugly against the back of the seat 22. The deflector also has a lip 32 which rests against the seat when the deflector is raised to prevent there being any air gap between the bottom of the deflector and the top of the seat. The lip also helps to limit clockwise movement of the deflector when it is raised.

In Figure 2, the datum line from which the effective height of the deflector is measured is indicated at 33, and the effective height is indicated by distance A. This height should be at least 100 mm and not so high as to obscure rear ward vision.

In Figure 3, which is to be regarded as solely schematic, the pivot axis 30 of the deflector 26 is supported in end plates 34 secured to the vehicle bodywork. Torsion coil springs 36 are fitted on the shaft to urge the deflector to its upright position as shown. The movement caused by the spring is limited by the lip 32 contacting the seat 22.

The deflector is moved from the raised position to the lowered position manually against the force of the springs 36. The deflector is then latched in the lowered position behind two spring-loaded latches 38 which are forced into the plates 34 as the deflector is moved past them, and then spring out to hold the deflector down against the force of the springs. In an alternative embodiment however, the lowering of the deflector when the hood is raised may also be accomplished automatically, being driven by the movement of the roof struts. For example there may be a continuous line connecting the deflector to the folding roof mechanism so that as the roof goes down, the deflector goes up and vice versa.

The folding roof is mounted on a frame, one strut 40 of which is shown in Figure 3 hinged on a plate 42 forming part of the bodywork. A Bowden cable 44 is connected between the strut 40 and the latches 38 with the cable sheath braced between end plates 46 and 48.

9s the roof is lowered, the strut 40 will move in the direction of the arrow 50. This will pull on the wire core of the Bowden cable 44 which will retract the latch 38 so allowing the springs 36 to raise the deflector. Although details of the cable and hood strut are shown only on one side of the mechanism in Figure 3, similar mechanisms will be used on both sides.

Although not shown, an auxiliary latching mechanism may be provided to hold the deflector down when the roof is lowered, if desired.

Claims

1. A car with a convertible roof and with an air deflector mounted in a generally upright position immediately behind the seat back of the rearmost row of seats.

2. 9 car as claimed in Claim 1, whereim the deflector is mounted so as to form an upwardly directed extension of the seat back of the rearmost row of seats.

3. A car as claimed in Claim 1 or Claim 2, wherein the deflector is mounted so that it can be lowered from its upright position when the roof is raised.

4. A car as claimed in Claim 3, wherein the deflector is spring loaded into its upright position and a latch is provided to hold the deflector in its lowered position.

5. A car as claimed in Claim 4, wherein the latch is automatically released when the hood is lowered, so that the spring-loading raises the deflector.

6. A car as claimed in Claim 4 or Claim 5, wherein a Bowden cable is connected to the hood frame to pull on and to release the latch on lowering of the hood.

7. z car as claimed in any one of Claims 3 to 6, wherein the deflector has a profile such that it conforms to the shape of the seat back when it is folded down.

8. A car as claimed in any preceding claim, wherein the top edge of the deflector extends at leats 100 mm above the datum line as hereinbefore defined.

9. An air deflector for a car with a convertible roof, the deflector including a deflector plate and means for mounting the deflector plate in a generally upright position immediately behind the seat back of the rearmost row of seats.

10. An air deflector as claimed in Claim 9 mounted on a horizontal hinge axis so that it can be moved between an upright position and a lowered position.

11. n air deflector as claimed in Claim 10, wherein a spring urges the deflector into its upright position and a latch is provided to hold the deflector in its lowered position.

12. A car with a convertible roof, substantially as herein described with reference to the accompanying drawings.

13. An air deflector for a car with a convertible roof, substantially as herein described with reference to the accompanying drawings.