GB2453340A - A device for reducing air pressure within a vehicle when a closure is closed - Google Patents

Abstract

A device is provided for facilitating the action of a closure on a vehicle. The closure may be the tailgate of the vehicle, and the device is required so that when the tailgate is closed a build up of air pressure within the vehicle is released so that the tailgate does not bounce back and fail to latch. The device comprises a flap 21 that is pivotable between an open position in which air can exit the vehicle and a closed position; means 22 for retaining the flap in the closed position; and a circuit for selectively de-activating the retaining means. The flap may be the glass of the tailgate, or it could be a separate flap, such as a drafter, on the body of the vehicle. The flap may be retained in a closed position by a mechanical latch, or by a series of permanent and electromagnets.

Description

A DEVICE FOR IMPROVING THE ACTION OF A VEHICLE CLOSURE

The present invention relates to a device for improving the action of a vehicle closure and, in particular, a device for improving the action of vehicle closures on large vehicles.

There is currently a trend within the automotive industry towards larger vehicles, both as a result of an increase of size within a given vehicle class and, in addition, an increasingly large spectrum of the vehicle buying public are opting to use SUVs, MPVs or similar vehicles. These vehicles are preferred by many users because of the high driving position and the easy access and flexible layout of the internal space. These advantages are provided through a combination of the provision of occasional seating rows and a combined occupant and cargo compartment. This flexible internal space is frequently accessed using a tailgate.

As vehicle size has increased within the class, the size of tailgate required has increased.

Tailgates are typically secured in a closed position using a mechanism consisting of a latch positioned on the vehicle and a striker mounted on the tailgate. The latch must cycle through an open position, in which the striker can be received by the latch and a closed position in which the striker is retained by the latch. The timing of this cycle is important because, if the latch cycles too quickly, it will have reached the closed position by the time the striker reaches the latch. This condition may result in damage to the latch.

When a tailgate is closed, it moves along an arcuate path and displaces a considerable amount of air as it moves. A proportion of this air moves into the interior of the vehicle as the tailgate is closed, creating a region of high pressure within the vehicle. As the tailgate reaches the closed position, the pressure differential between the interior of the vehicle and the atmosphere such that the tailgate opens again in order to allow the pressure to equalise more quickly than the latch can cycle and engage the striker. This phenomenon is sometimes referred to as tailgate "bounce." When tailgate bounce" has occurred the user will have to repeat the action of closing the tailgate, either by moving the closure through only a small proportion of its intended path in order to ensure that the build up of pressure within the vehicle interior is minimised, or by using a greater initial impulse to instigate the closure of the tailgate.

In order to avoid this problem, some manufacturers have chosen to power the closure of the tailgate in order that tailgate closure occurs in a slower and more controlled manner than during manual closure. Other manufacturers have chosen to provide a powered latch which operates to pull the tailgate closed when it has not latched fully. However, powered mechanisms for tailgates are expensive solutions and are not appropriate for all vehicles.

It is against this background that the present invention has been made.

According to the present invention there is provided a device for facilitating the action of a closure on a vehicle, the device comprising: a flap that is pivotable between an open position in which air can exit the vehicle and a closed position; means for retaining the flap in the closed position, and a circuit for selectively de-activating the retaining means.

The circuit may include a sensor configured to detect whether the vehicle closure is open or closed. Furthermore, the circuit may be configured to de-activate the retaining means when the vehicle closure is opened. Because the retaining means are de-activated as soon as the closure is opened, the switching does not have to be precisely timed as the device is ready to be closed as soon as the closure is opened.

The flap may be located on the closure. For example, when the closure is a tailgate and the flap is an opening tailgate window or hatch or, alternatively, a drafter.

The means for retaining the flap in an open position may be mechanical means.

Alternatively the means for retaining the flap in the closed position may comprise at least one electromagnet. In the case wherein the retaining means comprises at least one electromagnet, it may further comprise at least one permanent magnet. One advantage of the use of an arrangement including at least one permanent magnet is that the risk of battery drain is reduced. The use of a combination of magnets and electromagnets also ensures that there are no moving parts that can cause squeaks and rattles within the occupant compartment.

The circuit for selectively de-activating the retaining means may further comprise a timer for delaying the re-activation of the retaining means.

The present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 identifies a number of locations on a vehicle where a device according to the present invention could be deployed, Figure 2 shows an example of a device according to the present invention; Figures 3a to 3d show an example of a retaining means used as part of one example of the present invention, Figure 4 shows an exploded view of a further example of a device according to the present invention; and Figure 5 is a schematic representation of a circuit used to control the device shown in Figures 2 and 4.

Figure 1 shows the rear portion of a vehicle 19 with a tailgate 18. The tailgate 18 is illustrated in the closed position. A device 10 could form part of a hinged tailgate window or it could be an additional drafter 40 or rear air extractor.

A hinged tailgate window 20 can be provided to allow the user to open just a small portion of the tailgate in order to stow small items in the rearmost portion of the interior of the vehicle without needing to open the tailgate 18.

A rear air extractor or drafter is provided in most vehicles in order to provide a flow of air through the occupant compartment. The drafter typically comprises a one-way valve that is configured in order to allow air to flow through the occupant compartment and then to exit the vehicle without allowing any air to flow back into the vehicle. The drafter is typically provided, as illustrated by position 13 on Figure 1, towards the rear of the vehicle in order to ensure that the air circulates through the entirety of the occupant compartment before leaving the vehicle. The drafter can be positioned at any location that is substantially behind the occupant seating positions.

A device according to the present invention can be provided in the form of an additional modified drafter 40. The location of such a device will be chosen, not only according to the functionality of the device, but also taking into account the impact of the device on the styling of the vehicle.

Locations 14, 15, 16 are all suitable for a device 10 according to the present invention.

As a result of styling concerns location 16, in which the device 10 is positioned behind the number plate on the rear of the vehicle, is particularly appropriate. Furthermore, location 16 is one of the few locations in which a device 10 could practically be retrofitted to a vehicle. Because the space behind the number plate is limited, a single flap would have a limited angle of movement and therefore it might not be possible to provide sufficient air through flow. Therefore, a number of smaller flaps are provided. Each of the flaps is then able to move to a greater angle from the closed position in order to increase the maximum through flow of air in comparison with a single flap of the same cross sectional area.

Locations 14 and 15 are on the side of the vehicle. Location 14 is close to the door aperture and the device 10 must be positioned to be clear of the seal path of the door closure.

Although the examples that follow are described as being positioned and operated with respect to the closure of a vehicle tailgate, it will be apparent that, with suitable repositioning, the device 10 could also be applied to aiding the closure of large vehicle doors.

Each of the examples illustrated in the accompanying Figures includes a hinged flap, a device that can constrict the movement of the flap and a circuit that controls the device.

Figure 2 shows a device 10 incorporated into hinged tailgate window 20. The window glass 21 provides the hinged flap of the device 10. The window glass 21 is pivotably mounted to the vehicle using a hinge 24. The window 20 can be opened independently of the opening of the tailgate so that small items can be stowed in the interior of the vehicle without necessitating the opening of the tailgate. When the window 20 is closed it is held in place by a latching mechanism 22. The mechanism 22 is shown in more detail in Figures 3a to 3d.

The mechanism 22 consists of a motor 31 that powers a crank assembly 32 and a rod or cam 33 that is connected to the glass 21 so that, when the motor 31 operates, the window glass proceeds through the positions shown in Figures 3a to 3d. Figure 3a shows the closed position. This is the position in which the mechanism 22 is typically retained. Figure 3b shows a part open position, Figure 3c shows a fully open position and Figure 3d shows a second part open position that the mechanism passes through between fully open and returning to the fully closed position shown in Figure 3a.

The mechanism is tuned so that the window glass 21 is held in the closed position when the device is not in use. When the mechanism 22 ceases to hold the window glass 21 in the closed position, the window glass 21 is free to move to the part open position shown in Figure 3b.

Figure 4 shows a device 10 incorporated into a drafter 40 or rear air extractor. The drafter 40 typically consists of a one-way valve that has at least one flap 41 pivotally mounted on one edge of a frame 43. The flap 41 pivots to move between an open position and a closed position. In the open position, a distal portion of the flap 41 is not in contact with the frame 43 and thereby permits the flow of air through the drafter 40. In the closed position, the distal portion of the flap 41 is in contact with the frame 43 and thereby prevents the flow of air through the drafter 40.

The frame 43 is provided with either a ferrous insert 40a or one or more permanent magnets. A number of permanent magnets 45, 46, 47, 48, 49 are mounted on the internal surface of the flap 41. Between the ferrous insert 40a and the flap 41 is an electromagnet 44. The insert 40a, permanent magnets 45, 46, 47, 48, and 49 and the electromagnet 44 provide a device 42 that can be configured to constrict the movement of the flap 41 under certain circumstances.

In particular, when there is no current provided to the electromagnet, the permanent magnets 45 to 49 are attracted to the ferrous insert 40a, thus maintaining the flap 41 in a closed position. When the electromagnet 44 is activated, it provides sufficient repulsive force to overcome the attraction between the permanent magnets 45, 46, 47, 48, 49 and the insert 40a. This effectively de-activates the retaining means provided by the permanent magnets and the ferrous insert 40a and allows the flap 41 to be free to swing open in response to a pressure imbalance across the drafter 40. When the electromagnet 44 is de-activated, the magnetic attraction between the ferrous insert 40a and the permanent magnets 45 to 49 ensures that the drafter 40 returns to its closed position.

Although, in the examples above, the electromagnets and permanent magnets are described for use in the drafter 40 and the mechanism 22 is described for use with a pivotable window 20, each device 22, 42 could be used with each of the drafter 40 and the window 20. Furthermore, the examples described above may be created within a vehicle after the point of sale, i.e. during a retro-fit procedure.

Alternatively, the device can be provided ab initio as an additional feature. In this case, the positioning of the flap must be carefully selected in order to ensure that it is near enough to the closure to be aided and yet the provision of this feature does not adversely affect the styling of the vehicle.

As will be apparent from the description with reference to Figures 2 and 4 above, the device may be deployed either as a part of the closure or on a suitable part of the vehicle structure near to the closure.

Each of the examples described above with reference to Figures 2 and 4 is provided with a circuit 50 that controls the device 22, 42. A schematic representation of a circuit for controlling the devices 22, 42 is illustrated in Figure 5.

The circuit 50 includes a power supply 51, sensor 52 and a switch 53. The power supply 51 is taken from the vehicle's main electrical circuit although it could alternatively be provided by a small independent power source such as a battery. The sensor 52 is configured to identify whether the tailgate latch is closed or open, for example using logic gates to give an open circuit when the tailgate is closed and vice versa. The switch 53 is configured to operate the device 22, 42 depending on the output from the sensor 52.

When the tailgate latch is opened, the switch 53 activates the device 22, 42 which, in turn, frees the flap 21, 41 to allow it to move into an open position. In this way, as soon as the tailgate is opened, the device 10 is primed ready for the closure of the tailgate.

Whilst the tailgate remains open and during the subsequent closure of the tailgate, the device 10 enables the flap 21, 41 to move. Once the tailgate is latched, the device 22, 42 retains the flap 21, 41 can return to its closed position. A time delay circuit 54 is provided so that the re-activation of the retaining device 22, 42 is delayed by a predetermined time after the closure of the tailgate. In one example, the time delay circuit 54 is linked to the interior courtesy light of the vehicle so that the retaining means are re-activated as the courtesy light is switched off.

Claims (12)

1. A device for facilitating the action of a closure on a vehicle, the device comprising: a flap that is pivotable between an open position in which air can exit the vehicle and a closed position; means for retaining the flap in the closed position; and a circuit for selectively de-activating the retaining means.

2. The device according to claim 1, wherein the circuit includes a sensor configured to detect whether the vehicle closure is open or closed.

3. The device according to claim 2, wherein the circuit is configured to de-activate th retaining means when the vehicle closure is opened.

4. The device according to any one of the preceding claims, wherein the flap is located on the closure.

5. The device according to any one of claims 1 to 3, wherein the flap is located on the vehicle.

6. The device according to any one of claims 1 to 5, wherein the flap is a tailgate window glass.

7. The device according to any one of claims I to 5, wherein the flap is a drafter.

8. The device according to any one of claims I to 7, wherein the means for retaining the flap in the position are mechanical means.

9. The device according to any one of claims 1 to 7, wherein the means for retaining the flap in a closed position comprise at least one electromagnet.

10. The device according to claim 9, wherein the means for retaining the flap in the closed position further comprises at least one permanent magnet.

11. The device according to claim 9 or claim 10, wherein the circuit for selectively de-activating the retaining means further comprises a timer for delaying the re-activation of the retaining means.

12. The device as herein described with reference to Figures 2 to 5 of the accompanying drawings.