FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
AND
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
TITLE OF THE INVENTION
“AIR INLET GRILLE ASSEMBLY, VEHICLE AND VEHICLE COOLING
SYSTEM COMPRISING THE SAME, METHOD OF CONTROLLING ADMISSION OF AIR TO A VEHICLE COOLING SYSTEM, AND CONTROLLER FOR AN AIR INLET GRILLE ASSEMBLY
APPLICANT
i) Tata Motors Limited Of Bombay House, 24 Homi Mody Street, Mumbai 400001,
Maharashtra, India; An Indian Company; ii ) Tata Motors European Technical Centre
Plc Of 18 Grosvenor Place, London, Sw1x 7hs,, London, United Kingdom; United
Kingdom
The following specification particularly describes the invention and the manner
in which it is to be performed

FIELD OF INVENTION
The present disclosure relates to an air inlet grille assembly for a vehicle cooling system, a vehicle cooling system comprising such an air inlet grille assembly, a vehicle comprising such an air inlet grille assembly or such a vehicle cooling system, a method of controlling admission of air to a vehicle cooling system, a non-transitory computer readable medium bearing a computer program product or program code for executing such a method, and a controller for an air inlet grille assembly.
BACKGROUND OF INVENTION
A vehicle cooling system typically comprises, but is not limited to, a cooling pack for at least one of an engine, transmission and hydraulics of the vehicle, a condenser of an air conditioning unit of the vehicle, and a charge/induction-air heat exchanger, such as an intercooler. Typically, at least some of the elements of the vehicle cooling system are located near a front of the vehicle, behind an air inlet grille assembly, which contains one or more apertures, so that when the vehicle is moving forwards, the apertures encounter atmospheric air striking the front of the vehicle, and when the vehicle is motionless, the apertures are nonetheless in contact with ambient atmospheric air. The atmospheric air can therefore be used to provide cooling to some or all of the elements of the vehicle cooling system.
In order to control the amount of air admitted to the vehicle cooling system, it is known to occlude the one or more apertures of such an air inlet grille assembly, for example, by means of a sliding inlet cover. Some examples of such inlet covers are described in DE 492018 C, DE 198329 U, DE 3405107 A, DE 3701584 A, DE 10 2007 05353 B and FR 2 738 779 A. However, in general, these sliding inlet covers operate in a similar fashion to a roller blind for a window, which, in order to be drawn from a fully open to a fully closed position, must be moved all the way across the air inlet grille. This consumes a significant amount of energy, which if powered by the vehicle, must ultimately diminish the vehicle’s overall fuel efficiency.
Embodiments of the present invention have been conceived against this background.

SUMMARY OF THE INVENTION
Aspects and embodiments of the invention provide an air inlet grille assembly for a vehicle cooling system, a vehicle cooling system comprising such an air inlet grille assembly, a vehicle comprising such an air inlet grille assembly or such a vehicle cooling system, a method of controlling admission of air to a vehicle cooling system, a non-transitory computer readable medium bearing a computer program product or program code for executing such a method, and a controller for an air inlet grille assembly as claimed in the appended claims.
According to an aspect of the invention, there is provided an air inlet grille assembly for a vehicle cooling system. The air inlet grille assembly comprises a first inlet cover having an aperture formed therein, a second inlet cover having an aperture formed therein, and a motor. The second inlet cover is movable relative to the first inlet cover to at least partially align the aperture formed in the second inlet cover with the aperture formed in the first inlet cover. The motor is configured to move the second inlet cover relative to the first inlet cover in dependence on a cooling requirement of the vehicle cooling system until a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover admits an amount of air to the vehicle cooling system which substantially matches the cooling requirement of the vehicle cooling system.
Since the second inlet cover need only move a small distance relative to the first inlet cover before the degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover admits an amount of air to the vehicle cooling system which substantially matches the cooling requirement of the vehicle cooling system, this arrangement is highly energy efficient, in comparison to moving an inlet cover all the way across the air inlet grille from a fully open to a fully closed position. Moreover, at least one of the size, shape and position of the apertures respectively formed in the first and second inlet covers may be chosen for precise control of the air admitted to the vehicle cooling system, which also improves the energy efficiency of the vehicle. For example, with the invention, the location of the apertures may be precisely aligned with the locations of specific elements of the vehicle cooling system. In contrast, drawing a solid cover without any such aperture formed in therein across the air inlet grille would not allow for such precise control, particularly of the location where the air is admitted.

In some embodiments, the second inlet cover may also be movable by the motor relative to the first inlet cover to vary a direction of air admitted by the air inlet grille assembly to the vehicle cooling system as well. This allows, for example, for air to be directed towards different elements of the vehicle cooling system.
The second inlet cover may be movable by the motor relative to the first inlet cover by translation in a plane parallel to the first inlet cover.
Alternatively or additionally, the second inlet cover may be movable by the motor relative to the first inlet cover by rotation in a plane parallel to the first inlet cover.
One of the first and second inlet covers may be fixed relative to the vehicle cooling system and the other of the first and second inlet covers may be movable by the motor relative to the vehicle cooling system. This is more energy efficient than moving both the first and second inlet covers relative to the vehicle cooling system, although this is also possible.
The movable inlet cover may be at least partially segmented in the manner of a tambour door, in which case, the assembly can comprise a roller operable by the motor to roll up and unroll the movable inlet cover onto and from the roller, respectively, through an angle of less than one complete revolution of the roller.
In some embodiments, the movable inlet cover may be interposed between the fixed inlet cover and the vehicle cooling system. This has the advantage that the fixed inlet cover can protect the movable inlet cover from debris encountered when the vehicle is in motion.
The air inlet grille assembly may comprise a sealing element located between the first and second inlet covers, preventing flow of air between the first and second inlet covers in a plane parallel thereto. This has the advantages of preventing leakage of air when the apertures in the first and second inlet covers are not aligned with each other, as well as ensuring that if the apertures in the first and second inlet covers are at least partially aligned, the air is directed as desired.

The first and second inlet covers may each comprise a plurality of such apertures, one of which apertures formed in the second inlet cover and one of which apertures formed in the first inlet cover are both configured to be at least partially aligned with each other by the motor and with either a charge air cooler or a condenser of the vehicle cooling system. This allows these specific elements of the vehicle cooling system to be targeted with cooling air according to requirements.
The first and second inlet covers may each comprise a plurality of such apertures arranged in rows, and a separation between adjacent such rows on each of the first and second air inlet covers may be greater than or equal to a dimension of such apertures in a direction perpendicular to the rows in a plane parallel to the respective one of the inlet covers. This has the advantage of allowing the apertures in the second inlet cover to be completely occluded by the parts of the first inlet cover in between the rows of apertures in the first inlet cover when the apertures in the second inlet cover are not aligned with the apertures in the first inlet cover.
At least one of the shape, size and position of the aperture formed in the second inlet cover may be different from the respective one of the shape, size and position of the aperture formed in the first inlet cover. This allows for great versatility in the control of the air flow.
The motor may be adapted to overcome a force sticking the first and second inlet covers together before moving the second inlet cover relative to the first inlet cover. Such a sticking force may arise, for example, as a result of ingress of dust or dirt into the air inlet grille assembly, formation of ice during sub-zero temperatures and/or static friction.
In some embodiments, the air inlet grille assembly may comprise a heating element arranged to heat at least one of the first and second inlet covers. Such a heating element is advantageous in the removal of ice formed in sub-zero temperatures, to enable correct movement of the first and second inlet covers relative to each other.
In some embodiments, the air inlet grille assembly may comprise a third inlet cover movable by the motor relative to the first and second inlet covers in a direction substantially perpendicular to movement of the second inlet cover relative to the first inlet cover. If the third inlet cover also has an aperture formed therein, this is advantageous because it increases

the versatility which can be achieved in the control of the air admitted to the vehicle cooling system, by making at least one of the shape, size and position of the aperture formed in the third inlet cover different from the respective one of the shape, size and position of the apertures respectively formed in the first and second inlet covers.
In some embodiments, a majority of at least one of the inlet covers may be formed from a substantially rigid plastics material.
According to another aspect of the invention, there is also provided a vehicle cooling system comprising an air inlet grille assembly as described herein.
According to a further aspect of the invention, there is also provided a vehicle comprising an air inlet grille assembly as described herein or a vehicle cooling system as described herein.
According to yet another aspect of the invention, there is provided a method of controlling admission of air to a vehicle cooling system. The method comprises arranging an air inlet grille assembly as described herein between the vehicle cooling system and atmospheric air, and, in dependence on a cooling requirement of the vehicle cooling system, operating the motor of the assembly to move the second inlet cover relative to the first inlet cover of the assembly until a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover admits an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system.
The method may further comprise varying a direction of air admitted by the air inlet grille assembly to the vehicle cooling system by moving the second inlet cover relative to the first inlet cover by means of the motor.
According to a further aspect of the invention, there is also provided a controller for an air inlet grille assembly, wherein the air inlet grille assembly comprises a first inlet cover having an aperture formed therein, a second inlet cover having an aperture formed therein and a motor configured to move the second inlet cover relative to the first inlet cover. The controller comprises an input for receiving a cooling requirement of a vehicle cooling system, an output for transmitting a control signal to the motor of the air inlet grille assembly, and a processor. The processor is configured to determine, in dependence on a cooling requirement

of the vehicle cooling system received at the input, a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover which will admit an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system, and to transmit a control signal to the motor in accordance therewith via the output.
Another aspect of the invention also provides a non-transitory computer readable medium bearing a computer program product or program code for executing a method as described herein.
Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.
BRIEF DESCRIPTION OF THE DRAWINGS
One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
Fig. 1 is a partial front elevational view of an example of a vehicle;
Fig. 2A is a schematic side view of an embodiment of an air inlet grille assembly;
Fig. 2B is a schematic front view of elements of the air inlet grille assembly of Fig. 2A;
Fig. 3 is a schematic front view of elements of another embodiment of an air inlet grille assembly;

Fig. 4 is a schematic isometric exploded view of elements of a further embodiment of an air inlet grille assembly;
Fig. 5 is a schematic side view of elements of yet another embodiment of an air inlet grille assembly;
Fig. 6 is a schematic side view of elements of a still further embodiment of an air inlet grille assembly; and
Fig. 7 is a schematic flow diagram of an embodiment of a method of controlling admission of air to a vehicle cooling system.
DETAILED DESCRIPTION OF INVENTION
Fig. 1 shows an example of a vehicle 100, which in this case, is a light commercial vehicle. The vehicle 100 comprises a vehicle cooling system, which typically includes, but is not limited to, at least one of an engine, transmission and hydraulics cooling pack, an air conditioning condenser, and a charge/induction-air heat exchanger. The vehicle 100 also comprises an air inlet grille assembly, which will be described in greater detail below with reference to Figs. 2A and 2B. A part of this air inlet grille assembly which is visible in Fig. 1 is a first inlet cover 2, which has a plurality of apertures 4 formed therein, with the apertures 4 arranged in rows. The first inlet cover 2 is fixed in position relative to the vehicle cooling system. When the vehicle 100 is moving forwards, the apertures 4 encounter atmospheric air striking the front elevation of the vehicle 100. When the vehicle 100 is motionless, the apertures 4 are nonetheless in contact with ambient atmospheric air.
Figs. 2A and 2B show an embodiment of an air inlet grille assembly 1. The air inlet grille assembly 1 comprises the first inlet cover 2 also visible in Fig. 1 and a second inlet cover 6, which also has a plurality of apertures 8 formed therein, with the apertures 8 arranged in rows. A separation, s, between adjacent such rows on each of the first and second air inlet covers 2, 6 is greater than or equal to a dimension, d, of such apertures in a direction perpendicular to the rows in a plane parallel to the respective one of the inlet covers 2, 6, as

may be seen in Fig. 2B. With this arrangement of the apertures, if the apertures 8 in the second inlet cover 6 are not aligned with the apertures 4 in the first inlet cover 2, the apertures 8 in the second inlet cover 6 can be completely occluded by the parts of the first inlet cover 2 in between the rows of the apertures 4.
Whereas both of the first and second inlet covers 2, 6 are shown in the side view of Fig. 2A, in the front view of Fig. 2B, the first inlet cover 2 has been removed, better to reveal the second inlet cover 6, as well as other elements of the air inlet grille assembly 1. Thus, as may be seen, the air inlet grille assembly 1 further comprises a pair of rollers 10a, 10b, a motor 12, and a controller 20. The second inlet cover 6 is made of a flexible material and is mounted top and bottom on the rollers 10a, 10b. The second inlet cover 6 is movable relative to the first inlet cover 2 to at least partially align the apertures 8 formed in the second inlet cover 6 with the apertures 4 formed in the first inlet cover 2. The movable inlet cover 6 is therefore interposed between the fixed inlet cover 2 and the vehicle cooling system. The upper roller 10a can be driven to rotate by the motor 12 through an angle θ, as represented in Fig. 2A, under control of the controller 20. The lower roller 10b is resiliently biased to keep the second inlet cover 6 taut, and follows the rotational movement of the upper roller 10a. The second inlet cover 6 can therefore be moved by the motor 12 relative to the first inlet cover 2 by translation in a plane parallel to the first inlet cover 2, as represented in each of Figs. 2A and 2B by a straight double-headed arrow.
The controller 20 comprises an input 21 for receiving a cooling requirement of the vehicle cooling system, an output 22 for transmitting a control signal to the motor 12, and a processor 23. The processor 23 is communicably coupled to a computer readable storage medium 24, for example a computer memory, having stored thereon a set of instructions which when executed by the processor 23 implement the functionality described herein. The computer readable storage medium 24 may comprise part of the controller 20. The processor 23 is configured to determine, in dependence on a cooling requirement of the vehicle cooling system received at the input 21, a degree of superposition of the apertures 8 formed in the second inlet cover 6 with the apertures 4 formed in the first inlet cover 2 which will admit an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system, and to transmit a control signal to the motor 12 in accordance therewith via the output 22.

The motor 12 is configured to move the second inlet cover 6 relative to the first inlet cover 2 in dependence on the cooling requirement of the vehicle cooling system until a degree of superposition of the apertures 8 formed in the second inlet cover 6 with the apertures 4 formed in the first inlet cover 2 admits an amount of air to the vehicle cooling system which substantially matches the cooling requirement of the vehicle cooling system. Thus, in response to the control signal from the controller 20, the motor 12 moves the second inlet cover 6 to a position lying somewhere between or possibly at one of a first, fully open position, O, and a second, fully closed position, C, both of which are indicated in Fig. 2A. As may be seen in Fig. 2A, the angle θ is substantially less than one complete revolution of the rollers 10a, 10b. Thus a movement of the rollers 10a, 10b through only a small angle of rotation is sufficient to move the second inlet cover 6 between the fully closed position, C, and the fully open position, O. This is highly energy efficient, compared with moving second inlet cover 6 all the way across the first inlet cover 2 in the manner of a roller blind.
One of the apertures 8 formed in the second inlet cover 6 and one of the apertures 4 formed in the first inlet cover 2 are both configured to be at least partially aligned with each other by the motor 12 and with a charge air cooler of the vehicle cooling system. Another one of the apertures 8 formed in the second inlet cover 6 and another one of the apertures 4 formed in the first inlet cover 2 are both configured to be at least partially aligned with each other by the motor 12 and with a condenser of the vehicle cooling system. Thus when the degree of superposition of the apertures 8 formed in the second inlet cover 6 with the apertures 4 formed in the first inlet cover 2 admits an amount of air to the vehicle cooling system which substantially matches the cooling requirement of the vehicle cooling system, both the charge air cooler and the condenser of the vehicle cooling system receive a flow of cooling air.
As may be seen in Fig. 2B, in this embodiment, the air inlet grille assembly 1 also comprises a heating element 18 arranged to heat the second inlet cover 6. The heating element 18 is in the form of a flexible resistive wire bonded to the second inlet cover 6, which becomes warm when an electrical current is passed through it. This can be used to unfreeze the air inlet grille assembly 1 in the event that the vehicle is being operated in sub-zero temperatures, causing any mechanical components of the assembly 1 to seize up. The motor 12 is nonetheless also adapted to overcome any force sticking the first and second inlet covers 2, 6 together, before moving the second inlet cover 6 relative to the first inlet cover 2. The output

of the motor 12 may be suitably geared to increase the torque it can apply to roller 10a, in order to achieve this.
Fig. 3 shows the second inlet cover 46 and rollers 10a, 10b in another embodiment of an air inlet grille assembly. As may be see, the second inlet cover 46 differs from the second inlet cover 6 of the air inlet grille assembly 1 shown in Figs. 1, 2A and 2B. In all other respects, however, this other embodiment of an air inlet grille assembly is constructed and functions in the same manner as the air inlet grille assembly 1 of Figs. 1 to 2B. In this embodiment, instead of being made of a flexible material like the second inlet cover 6, a majority of the second inlet cover 46 is formed from a substantially rigid plastics material. However, the second inlet cover 46 is at least partially segmented into a plurality of elongate segments 14 each made of this substantially rigid plastics material, which are connected to each other, in the manner of a tambour door. The roller 10a is therefore operable by the motor 12 to roll up and unroll the movable inlet cover 46 onto and from the roller 10a, respectively, through an angle θ of less than one complete revolution of the roller.
Fig. 4 shows elements of a further embodiment of an air inlet grille assembly 51. The air inlet grille assembly 51 comprises a first inlet cover 52, a second inlet cover 56, a first set of ducts 28a and a second set of ducts 28b. The first inlet cover 52 has a plurality of apertures 4a, 4b formed therein, which are arranged in two rows. The second inlet cover 56 also has a plurality of apertures 8 formed therein, which are arranged in only a single row. As may be seen, therefore, at least one of the shape, size and position of the apertures 8 formed in the second inlet cover 56 is different from the respective one of the shape, size and position of the apertures 4a, 4b formed in the first inlet cover 52.
The second inlet cover 56 is movable relative to the first inlet cover 52 to at least partially align the apertures 8 formed in the second inlet cover 56 either with the apertures 4a formed in the first inlet cover 52 or with the apertures 4b formed in the first inlet cover 52. In order to achieve this, the air inlet grille assembly 51 further comprises a motor configured to move the second inlet cover 56 relative to the first inlet cover 52 in dependence on a cooling requirement of the vehicle cooling system until a degree of superposition of the apertures 8 formed in the second inlet cover 56 with the apertures 4a or 4b formed in the first inlet cover 52 admits an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system, in a similar manner to that described above in

relation to Figs. 1 to 2B. However, in this embodiment, when the apertures 8 are at least partially aligned with the apertures 4a formed in the first inlet cover 52, incoming air 26 is directed through the first set of ducts 28a in direction A, whereas when the apertures 8 are at least partially aligned with the apertures 4b formed in the first inlet cover 52, incoming air 26 is instead directed through the second set of ducts 28b in direction B. Thus the second inlet cover 56 can be moved by the motor 12 relative to the first inlet cover 52 to vary a direction of the air 26 admitted by the air inlet grille assembly 51 to the vehicle cooling system.
Fig. 5 shows a side view of elements of yet another embodiment of an air inlet grille assembly. This air inlet grille assembly is substantially the same as that described above in relation to Figs. 1 to 2B, except that mounted on the second inlet cover 6 are a plurality of sealing elements 16 located between the first and second inlet covers 2, 6, which prevent the flow of air between the first and second inlet covers 2, 6 in a plane parallel thereto. In this embodiment, the sealing elements 16 take the form of a wall of resilient material, such as rubber, mounted on the second inlet cover 6 and which surrounds each of the apertures 8 of the second inlet cover 6. These circumferential walls surrounding each of the apertures 8 may therefore be seen in cross-section in Fig. 5. As may also be seen, the first and second inlet covers 2, 6 are sufficiently close to each other in this embodiment that as the second inlet cover 6 moves, the sealing elements 16 come into contact with an opposing major surface of the first inlet cover 2. The sealing elements 16 thus ensure that incoming air is directed as intended when the apertures 8 formed in the second inlet cover 6 are at least partially aligned with the apertures 4 formed in the first inlet cover 2, and that when the apertures 4, 8 are not thus aligned, none of the incoming air can flow between the first and second inlet covers 2, 6.
Fig. 6 shows a side view of elements of a still further embodiment of an air inlet grille assembly. This air inlet grille assembly is substantially the same as that described above in relation to Figs. 1 to 2B, except that it also comprises a third inlet cover 30 interposed between the first and second inlet covers 2, 6. The third inlet cover 30 is movable by the motor 12 relative to the first and second inlet covers 2, 6 in a direction which is substantially perpendicular to movement of the second inlet cover 6 relative to the first inlet cover 2. As viewed in Fig. 6, therefore, this direction is into and out of the page. The third inlet cover 30 is constructed and functions in a similar manner to the second inlet cover 6. In other words, it also comprises at least one aperture formed therein, which can be at least partially aligned

with the apertures 4, 8 formed in the first and second inlet covers 2, 6 by movement of a corresponding set of rollers similar in structure and function to the rollers 10a, 10b under control of the controller 20, in order to admit an amount of air to the vehicle cooling system which substantially matches the cooling requirement of the vehicle cooling system. By making at least one of the shape, size and position of the aperture formed in the third inlet cover different from the respective one of the shape, size and position of an aperture formed in the first and second inlet covers, great versatility can be achieved in the control of the air admitted to the vehicle cooling system.
Whereas in Figs. 1 to 6, the first, second and third inlet covers 2, 6, 30 are all shown to be substantially flat, at least one or all of them may instead be curved, in order to suit the overall shape, position and profile of a vehicle and/or of a vehicle cooling system. In case a curved inlet cover is movable, the air inlet grille assembly may also comprise one or more guide rails for an edge or edges of the movable inlet cover, and the movable inlet cover can be guided by these guide rails in order to maintain its curved shape.
Furthermore, whereas in all of Figs. 1 to 6, the second and third inlet covers 6, 30 are shown to be movable by the motor 12 relative to the first inlet cover 2 by translation in a plane which is parallel to the first inlet cover 2, either or both of the second and third inlet covers 6, 30 may instead be movable by the motor 12 relative to the first inlet cover 2 by rotation in the plane parallel to the first inlet cover 2. This may be achieved in one of several ways, for example, by pivoting the second or third inlet cover 6, 30 about one of its corners or by rotating the respective cover about an axis at or near to its centre, rather than by translating the cover using rollers similar to the rollers 10a, 10b depicted in the drawings. In such a case, it is preferable that the second and/or third inlet cover 6, 30 should be formed from a substantially rigid plastics material.
Fig. 7 shows an embodiment of a method 60 of controlling admission of air to a vehicle cooling system. In Fig. 7, box 61 represents arranging an air inlet grille assembly of a type described herein between the vehicle cooling system and atmospheric air. Box 62 represents, in dependence on a cooling requirement of the vehicle cooling system, operating the motor of the assembly to move the second inlet cover relative to the first inlet cover of the assembly until a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover admits an amount of air to the vehicle cooling system

substantially matching the cooling requirement of the vehicle cooling system. Box 63 represents varying a direction of air admitted by the air inlet grille assembly to the vehicle cooling system by moving the second inlet cover relative to the first inlet cover by means of the motor.
For the purposes of this disclosure, it is to be understood that the control systems described herein can each comprise a control unit or computational device having one or more electronic processors. A vehicle and/or a system thereof may comprise a single control unit or electronic controller or alternatively different functions of the controllers may be embodied in, or hosted in, different control units or controllers. A set of instructions could be provided which, when executed, cause said controllers or control units to implement the control techniques described herein, including the described methods. The set of instructions may be embedded in one or more electronic processors, or alternatively, the set of instructions could be provided as software to be executed by one or more electronic processors. For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present disclosure is not intended to be limited to any particular arrangement. In any event, the set of instructions described above may be embedded in a computer-readable storage medium (e.g., a non-transitory storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.
The boxes illustrated in Fig. 7 may represent steps in a method and/or sections of code in a computer program. The illustration of a particular order to the blocks does not necessarily imply that there is a required or preferred order for the blocks and the order and arrangement of the block may be varied. Furthermore, it may be possible for some steps to be omitted.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.
Features described in the preceding description may be used in combinations other than the combinations explicitly described.
Although functions have been described with reference to certain features, those functions may be performable by other features, whether described or not.
Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.
Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance, it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings, whether or not particular emphasis has been placed thereon.

WE CLAIM
1. An air inlet grille assembly for a vehicle cooling system, the assembly comprising:
a first inlet cover having an aperture formed therein;
a second inlet cover having an aperture formed therein;
wherein the second inlet cover is movable relative to the first inlet cover to at least partially align the aperture formed in the second inlet cover with the aperture formed in the first inlet cover; and
a motor configured to move the second inlet cover relative to the first inlet cover in dependence on a cooling requirement of the vehicle cooling system until a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover admits an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system.
2. An air inlet grille assembly according to claim 1, wherein the second inlet cover is movable by the motor relative to the first inlet cover to vary a direction of air admitted by the air inlet grille assembly to the vehicle cooling system.
3. An air inlet grille assembly according to claim 1 or claim 2, wherein the second inlet cover is movable by the motor relative to the first inlet cover by translation in a plane parallel to the first inlet cover.
4. An air inlet grille assembly according to any one of the preceding claims, wherein the second inlet cover is movable by the motor relative to the first inlet cover by rotation in a plane parallel to the first inlet cover.
5. An air inlet grille assembly according to any one of the preceding claims, wherein one of the first and second inlet covers is fixed relative to the vehicle cooling system and the other of the first and second inlet covers is movable by the motor relative to the vehicle cooling system.
6. An air inlet grille assembly according to claim 5, wherein the movable inlet cover is at least partially segmented in the manner of a tambour door and the assembly comprises a

roller operable by the motor to roll up and unroll the movable inlet cover onto and from the roller, respectively, through an angle of less than one complete revolution of the roller.
7. An air inlet grille assembly according to claim 5 or claim 6, wherein the movable inlet cover is interposed between the fixed inlet cover and the vehicle cooling system.
8. An air inlet grille assembly according to any one of the preceding claims, comprising a sealing element located between the first and second inlet covers, preventing flow of air between the first and second inlet covers in a plane parallel thereto.
9. An air inlet grille assembly according to any one of the preceding claims, wherein the first and second inlet covers each comprise a plurality of such apertures, one of which apertures formed in the second inlet cover and one of which apertures formed in the first inlet cover are both configured to be at least partially aligned with each other by the motor and with a charge air cooler or condenser of the vehicle cooling system.
10. An air inlet grille assembly according to any one of the preceding claims, wherein the first and second inlet covers each comprise a plurality of such apertures arranged in rows, and a separation between adjacent such rows on each of the first and second air inlet covers is greater than or equal to a dimension of such apertures in a direction perpendicular to the rows in a plane parallel to the respective one of the inlet covers.
11. An air inlet grille assembly according to any one of the preceding claims, wherein at least one of the shape, size and position of the aperture formed in the second inlet cover is different from the respective one of the shape, size and position of the aperture formed in the first inlet cover.
12. An air inlet grille assembly according to any one of the preceding claims, wherein the motor is adapted to overcome a force sticking the first and second inlet covers together before moving the second inlet cover relative to the first inlet cover.
13. An air inlet grille assembly according to any one of the preceding claims, comprising a heating element arranged to heat at least one of the first and second inlet covers.

14. An air inlet grille assembly according to any one of the preceding claims, comprising a third inlet cover having an aperture formed therein, movable by the motor relative to the first and second inlet covers in a direction substantially perpendicular to movement of the second inlet cover relative to the first inlet cover.
15. An air inlet grille assembly according to any one of the preceding claims, wherein a majority of at least one of the inlet covers is formed from a substantially rigid plastics material.
16. A vehicle cooling system comprising an air inlet grille assembly according to any one of the preceding claims.
17. A vehicle comprising an air inlet grille assembly according to any one of claims 1 to 15 or a vehicle cooling system according to claim 16.
18. A method of controlling admission of air to a vehicle cooling system, the method comprising:
arranging an air inlet grille assembly according to any one of claims 1 to 15 between the vehicle cooling system and atmospheric air; and
in dependence on a cooling requirement of the vehicle cooling system, operating the motor of the assembly to move the second inlet cover relative to the first inlet cover of the assembly until a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover admits an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system.
19. A method of controlling admission of air to a vehicle cooling system according to claim 18, the method comprising varying a direction of air admitted by the air inlet grille assembly to the vehicle cooling system by moving the second inlet cover relative to the first inlet cover by means of the motor.
20. A controller for an air inlet grille assembly, wherein the air inlet grille assembly comprises a first inlet cover having an aperture formed therein, a second inlet cover having an aperture formed therein and a motor configured to move the second inlet cover relative to the first inlet cover, the controller comprising:

an input for receiving a cooling requirement of a vehicle cooling system;
an output for transmitting a control signal to the motor of the air inlet grille assembly; and
a processor configured to determine, in dependence on a cooling requirement of the vehicle cooling system received at the input, a degree of superposition of the aperture formed in the second inlet cover with the aperture formed in the first inlet cover which will admit an amount of air to the vehicle cooling system substantially matching the cooling requirement of the vehicle cooling system, and to transmit a control signal to the motor in accordance therewith via the output.
21. A non-transitory computer readable medium bearing a computer program product or
program code for executing a method according to claim 18 or claim 19.