HK1070335B - Air intake for motor vehicles - Google Patents

Description

Automobile air inlet

Technical Field

The present invention relates to an air intake for a motor vehicle, and in particular to an air intake with variable geometry for cooling the engine of a racing vehicle.

Background

Automobile air intakes are known, as according to WO 01/46570, which comprise at least one deflector provided with one or several walls adapted to convey air through an opening formed in the bodywork and directed towards the front of the automobile. On the one hand these air intakes deteriorate the aerodynamic characteristics of the car and on the other hand they must have large dimensions when the engine is very powerful, as in racing cars where the best aerodynamic characteristics are really important. In fact, if the air intake is not of the proper size, the engine may dangerously overheat.

Disclosure of Invention

It is therefore an object of the present invention to provide an air intake which does not have the above-mentioned disadvantages.

To this end, the invention provides an air intake assembly for a motor vehicle, comprising at least one deflector provided with one or several walls adapted to convey air through an opening formed in the bodywork of the motor vehicle, wherein said deflector is hinged to at least one member of the motor vehicle, the deflector being rotated about an axis by at least one motor so as to vary the size of said opening, characterized in that: the angle included between the axis of rotation of the deflector and the vertical plane of symmetry of the vehicle is not greater than 45 °.

Due to the movement system of the deflector, the air intake of the invention can vary its geometrical dimensions and then modify the air flow entering one or several radiators according to the need for cooling. With this arrangement, it is therefore possible to adopt a smaller air inlet opening size when the inlet air is sufficient to cool the engine, thereby optimising the aerodynamic properties of the vehicle. This is important at high speeds, where the aerodynamic properties of the vehicle severely affect the performance of the vehicle.

In order to further improve the aerodynamic properties of the vehicle, it has been found that the angle included between the axis of rotation of the deflector and the vertical symmetry plane of the vehicle is preferably not more than 45 °, more preferably less than 5 °. With this arrangement, the pneumatic load on the deflector and against its movement is also reduced, with a consequent reduction in the risk of damage to the motor driving it.

In addition, properly shaping the deflector wall and the body portion below it, and positioning the hinge toward the center axis of the vehicle, further improves the aerodynamic characteristics of the invention in the closed and open positions.

According to a particular aspect of the invention, the deflector position of the air intake is not only related to the speed of the vehicle, but also to the speed of its engine, and to the temperature of the cooling liquid and/or of the outside air, so that the deflector is opened only when it is really necessary.

According to another advantageous aspect of the invention, the air inlet is controlled by a device which not only precisely rotates the deflector, but also verifies its correct position and working condition. For this purpose, the electronic control device is preferably provided with an encoder, a PWM device and an electronic computing device, for example a microprocessor. In addition, the control device allows to determine obstacles, if any, affecting the movement of the deflector and immediately signal the user of the vehicle.

According to a further advantageous aspect of the invention, the deflector movement may be manually controlled by the user, for example for work trials or other purposes.

Drawings

Other advantages and features of the air intake of the present invention will be apparent to those skilled in the art from the following detailed and non-limiting description of an embodiment thereof, which is made with reference to the accompanying drawings.

FIG. 1 shows a partial front perspective view of an automobile with closed air intake ports;

FIG. 2 illustrates a partial front perspective view of the automobile of FIG. 1 with an open air intake;

FIG. 3 illustrates a partial rear perspective view of the automobile of FIG. 1 with the air intake closed;

FIG. 4 illustrates a partial rear perspective view of the automobile of FIG. 1 with the air intake open;

FIG. 5 illustrates a front perspective view of the air inlet deflector of FIG. 1;

FIG. 6 illustrates a rear perspective view of the air inlet deflector of FIG. 1;

FIG. 7 shows a cross-sectional view of the rear portion of the air intake of FIG. 1;

FIG. 8 shows a schematic longitudinal cross-sectional view of the air inlet of FIG. 1;

FIG. 9 shows a cross-sectional view of a middle portion of the intake port of FIG. 1;

FIG. 10 shows a schematic electrical diagram of the air intake control apparatus of FIG. 1; and

fig. 11 shows a flow chart of the operation of the air intake of fig. 1.

Detailed Description

Referring to fig. 1 to 6, it can be seen that the air intake of the embodiment of the present invention includes a deflector 1 which is hinged to a member of a vehicle 2. The movable deflector 1 can thus be rotated about the axis 3, so as to vary the size of the opening 4 formed in the body 2 and directed towards the front of the vehicle.

In particular, the angle included between the axis of rotation 3 of the deflector 1 and the vertical plane of symmetry of the vehicle is not more than 45 °, preferably less than 5 °, i.e. the axis of rotation 3 is substantially parallel to the direction of motion of the vehicle. In order to send air into the vehicle 2 through the opening 4, the deflector 1 comprises a side wall 5 and a rear wall 6. To improve the aerodynamic characteristics, the side walls 5 are preferably convex and substantially rectangular, while the rear wall is preferably concave and substantially half-conical, with the base facing the outside of the vehicle 2.

Referring to fig. 7 and 8, it can be seen that the deflector 1 is hinged to a portion 7 of the frame of the vehicle 2, with one or more hinges 8 towards the central axis of the vehicle, so that the side wall 5 faces outwards. The deflector 1 further comprises an inner wall 9, which is inclined and shaped to convey air from the opening 4 downwards. For this purpose, the body 2 is shaped so as to obtain a channel 10 defined by an outer side wall 11, an inner side wall 12 and a lower wall 13, which conveys the air coming from the opening 4 to the radiator (not shown) of the vehicle 2. In the case of a vehicle with a central or rear engine, it is preferable to provide a pair of air intakes of the invention above the fender of each rear wheel, with the deflector 1 aligned with the body 2 in the closed position, and the slot 10 formed in the same body below the deflector 1. In fig. 7 the fluid director 1 is shown in an open position by means of dashed lines 14, and in fig. 8 the fluid director is shown in a closed position by means of dashed lines 15.

Referring now to fig. 9, it can be seen that the deflector 1 can be rotated in the direction of arrow 16 by a piston 17 which can be run into a cylinder 18 and driven by a motor 19, for example a Microwin 1: 50 lent motor, manufactured by OSLV, italy. The free end of the piston 17 is hinged to a lever 20 fixed to the deflector 1, while the cylinder 18 is hinged to a bracket 21 fixed to a member 22 of the vehicle 2, for example a part of the frame. In the figure, the deflector 1 is shown in the open position by a dashed line 23.

Referring to fig. 10, it can be seen that the air intake of the present invention comprises an electronic device 24 adapted to control one or several motors 19 to rotate one or several deflectors 1. The control device 24 comprises in particular an electronic computing means 25, for example an 8-bit Motolola MC68HC908AZ60 microprocessor, with a variable internal timing setting of 16MHz, powered by a 400mA power supply 26, which is overload-protected and connected to the power supply line of the car 2.

The microprocessor 25 is connected to one or several memories, in particular to a 60kB Flash memory 27, a 2kB RAM memory 28 and a 1kB EEPROM memory 29, which store data and programs for the microprocessor 25, and to a PWM (pulse width modulator) for controlling the motor 19. In particular, the PWM device 30 is connected to the motor 19 to convert the control signal output from the microprocessor 25 into a signal having a constant voltage and a variable duty cycle. It is therefore possible to intervene in the supply of electric power to the motor to vary the speed of the motor 19. The duty cycle of the above signals is actually calculated by the microprocessor 25, depending on the speed of the car 2 and the position of the deflector 1. This position is suitably detected again by an encoder 31 for each motor 19 and connected to the microprocessor 25 via an interface 32. The encoder is for example a well-known Hall-effect encoder, generally included in the same motor 19 and measures the displacement of the deflector 1 or of a member connected thereto, such as a piston, with respect to the end-stroke position, in particular corresponding to the closure of the air inlet, i.e. to the zero position of the encoder 31.

The electric power supplied by the PWM device 30 is the product of the current intensity circulating in the motor 19 (proportional to the torque supplied by the motor itself) and the feed voltage, to which the maximum speed achievable by the motor 19 is related. Thus measuring the current circulating in the motor 19 results in a torque generated by the motor and then in a force acting on the deflector 1.

The microprocessor 25 verifies whether the current supplied to the motor 19 is adapted to the correct operating conditions of the deflector 1, by means of a series of threshold values stored in one or several memories 27, 28 and 29, which are related to the type of movement required and to the PWM signal delivered by the device 30. If the current is too low, the microprocessor 25 recognizes an abnormal operating condition, such as the motor 19 being open or its mechanical drive being idle. If, on the other hand, the current exceeds a preset threshold value, i.e. the force exerted on the deflector 1 becomes excessive, the microprocessor 25 verifies the position of the deflector 1 itself by means of an encoder 31. If the distance from the desired position is less than a predetermined threshold value, the microprocessor 25 detects that the deflector 1 has reached the end-of-travel position and stops it. If, on the other hand, the distance from the desired position is greater, the microprocessor 25 recognizes that an obstacle is present.

This condition may be detrimental because the obstruction may represent a human limb, such that the microprocessor 25 immediately reverses its motion, forcing the deflector 1 to the starting position, allowing the obstruction to be removed, and thereafter trying to bring the deflector 1 to the desired position. If the obstacle has not been removed, the reverse cycle of movement is repeated a predetermined number of times and then the desired position is sought to be restored, after which the microprocessor 25 stops the deflector 1, thereby alerting the user to an abnormal operating condition by means of a signal device, for example a signal lamp 33, provided on the control panel of the car 2 and connected to the microprocessor 25 via a data interface 34. It is clear that the microprocessor 25 also recognizes the end of the movement each time the number of steps of the motor 19 detected by the encoder 31 is equal to a predetermined number of steps.

The microprocessor 25 is also connected, through an interface 34, for example of the CAN (controlled area network) type, to a plurality of external sensors, also of known type, such as a sensor 35 adapted to measure the speed of the vehicle 2, a sensor 36 adapted to measure the speed of the vehicle's engine, a sensor 37 adapted to measure the temperature of the vehicle's engine coolant, and a sensor 38 adapted to measure the temperature of the external air. These sensors are generally already provided in the racing vehicle and are connected to an electronic control unit 39, which electronic control unit 39 controls the operating state of the vehicle itself and can be connected to the interface 34. The microprocessor 25 is also connected to a serial interface 40 for transmitting and receiving external data, and to a data interface 41, in turn to a button 42 provided in the cab of the vehicle 2 for manually controlling the movement of the deflector 1.

Referring now to fig. 11, it can be seen that the request to open or close the deflector 1 can be sent manually by the user through the button 42 or automatically by the microprocessor 25 when a predetermined threshold value stored in one or several of the memories 27, 28 and 29 is related to the temperature of the air measured by the sensor 38 or to the temperature of the cooling liquid measured by the sensor 37. The temperature threshold for which closure is required is preferably lower than the temperature value for which opening is required, so that annoying vibrations of the flow deflector 1 are avoided.

In order to effectively translate the request to perform a movement into a command to the electric machine 19, the engine speed of the vehicle 2 detected by the sensor 36 must be greater than a threshold value, for example greater than zero, while the speed of the vehicle 2 detected by the sensor 35 must be lower than one or several stored threshold values, for example a first maximum speed value for automatic movement caused by the sensor 37 or 38, or a second maximum speed value for manual movement caused by the button 42.

In addition, since the possibility of starting the movement of the deflector 1 is suppressed by the speed of the automobile 2, the possibility of the same deflector 1 moving is also suppressed by the same speed threshold value. If the vehicle 2 exceeds this threshold value and the deflector 1 has started to move, it is always switched to an opening movement in order to avoid excessive mechanical stresses of the structure due to the aerodynamic forces acting on the deflector 1 at high speed. For example, the maximum speed threshold value may be equal to 180km/h, so that beyond this value the movement of the deflector 1 may be stopped or, if movement has already started, forced to a position, in particular an open position.

In the table below, an example of threshold values is shown, which may be programmed for the position of the deflector 1.

TABLE 1 threshold value example

Cooling liquid temperature of [ deg.C]	Air temperature [ deg.C ]]	Speed of vehicle [ km/h]	Position of the flow guider
				T＜80	T＜80	V＜180	Close off
T＜80	30＜T＜38	V＜180	Close off
				T＜80	T＞38	V＜180	Close off
80＜T＜95	T＜30	V＜180	Close off
				80＜T＜95	30＜T＜38	V＜180	Open
80＜T＜95	T＞38	V＜180	Open
				T＞95	T＜30	V＜180	Open
T＞95	30＜T＜38	V＜180	Open
				T＞95	T＞38	V＜180	Open

The movement of the air deflector 1 can then be continuously inhibited to satisfy the following four controls:

and (3) control 1: if the vehicle 2 exceeds a predetermined speed threshold value, the movement is switched to the open position. The possibility of movement of the deflector 1 is further restored only when the speed of the vehicle 2 is at the threshold value minus a hysteresis value, in order to avoid fluttering of the air intake.

And (3) control 2: if the current into the motor 19 is less than a predetermined minimum current value, i.e. a mechanical or electrical fault in the motor itself is detected, the movement is stopped and the microprocessor 25 signals a malfunction by means of the signal lamp 33.

And (3) controlling: if the current into the motor 19 is greater than a predetermined maximum current value over an excessive distance from the desired position, the presence of an obstacle is detected or the movement of the deflector 1 is considered to be stopped.

And (4) control: the movement of the deflector 1 is stopped when the position obtained by the encoder 31 is equal to the desired position.

As described above, the position of the fluid director 1 is obtained by the encoder 31 counting the revolutions of the motor 19, thereby determining the displacement of the piston 17 with respect to the zero position. Then, with each movement of the deflector, the position of the deflector 1 with respect to zero is determined and stored, which either ends definitively or is interrupted by a malfunction or the presence of an obstacle. It is therefore necessary to determine the movement of the deflector 1 with respect to an exact zero position. For this purpose, a possibility is provided for carrying out a resetting operation, which brings the fluid deflector 1 into the closed position until a predetermined current threshold value is exceeded. After this operation is performed, the incremental count of the encoder 31 is set to zero.

In this resetting operation, the safety function is not active, so that in order to avoid a danger, the request should be made only by an identification device which is held by an authorized repair shop.

Changes and additions may be made by those skilled in the art to the embodiments described and illustrated above while remaining within the scope of the present invention.

Claims (20)

1. An air intake assembly for a motor vehicle, comprising at least one air deflector (1) provided with one or several walls (5, 6, 9) adapted to convey air through an opening (4) formed in the body of the motor vehicle (2), wherein said air deflector (1) is hinged to at least one member (7) of the motor vehicle (2), the air deflector (1) being rotated about an axis (3) by at least one electric motor (19) so as to vary the size of said opening (4), characterized in that: the angle included between the axis of rotation (3) of the deflector (1) and the vertical plane of symmetry of the vehicle (2) is not greater than 45 °.

2. The air intake assembly of a vehicle of claim 1, wherein: the included angle between the rotation axis (3) of the deflector (1) and the vertical symmetry plane of the vehicle (2) is less than 5 degrees.

3. The air intake assembly of an automobile according to claim 1 or 2, wherein: the deflector (1) comprises a convex and substantially rectangular side wall (5).

4. The air intake assembly of an automobile according to claim 1 or 2, wherein: the deflector (1) comprises a concave and substantially semi-conical rear wall (6) with its base facing the outside of the vehicle (2).

5. The air intake assembly of an automobile according to claim 1 or 2, wherein: the deflector (1) is hinged to at least one member (7) of the vehicle (2) by means of one or more hinges (8) towards the central axis of the vehicle itself.

6. The air intake assembly of an automobile according to claim 1 or 2, wherein: the deflector (1) comprises an inner wall (9) which is inclined and shaped to convey air from the opening (4) downwards.

7. The air intake assembly of an automobile according to claim 1 or 2, wherein: the body of the vehicle (2) is shaped to form a channel (10) defined by an outer side wall (11), an inner side wall (12) and a lower wall (13) for conveying air from the opening (4) to the radiator of the vehicle (2).

8. The air intake assembly of a vehicle of claim 7, wherein: the air inlet is arranged above the fender of the rear wheel of the vehicle (2), the deflector (1) is aligned with the body of the vehicle (2) in the closed position, and a groove (10) is formed in the same body below the deflector (1).

9. The air intake assembly of an automobile according to claim 1 or 2, wherein: the deflector (1) is rotatable by a piston (17) which can be moved into a cylinder (18) and is driven by an electric motor (19), wherein the free end of the piston (17) is hinged to a lever (20) fixed to the deflector (1) and the cylinder (18) is hinged to a bracket (21) fixed to a component (22) of the vehicle (2).

10. The air intake assembly of an automobile according to claim 1 or 2, wherein: the air intake comprises an electronic device (24) adapted to control at least one electric motor (19) to rotate at least one air deflector (1), and an electronic computing means (25) powered by a power supply (26) connected to the power line of the vehicle (2) and connected to one or more memories (27, 28, 29) storing data and programs of said electronic computing means (25).

11. The air intake assembly of a vehicle of claim 10, wherein: said electronic computing means (25) comprise a Motolola MC68HC908AZ60 microprocessor and said memories (27, 28, 29) comprise a Flash memory (27), a RAM memory (28) and an EEPROM memory (29).

12. The air intake assembly of a vehicle of claim 10, wherein: said electronic computing means (25) are connected to at least one PWM device (30) connected to at least one electric motor (19) and adapted to convert the control signal output of the electronic computing means (25) into a signal having a constant voltage and a variable duty cycle.

13. The air intake assembly of a vehicle of claim 10, wherein: the position of the deflector (1) is detected by at least one encoder (31) for the motor (19) and connected to the electronic computing means (25) through an interface (32).

14. The air intake assembly of a vehicle of claim 10, wherein: the electronic computing means (25) are connected to a sensor (35) adapted to measure the speed of the vehicle (2) to automatically determine the movement of the deflector (1) according to threshold values of the speed of the vehicle (2) stored in said memory (27, 28, 29).

15. The air intake assembly of a vehicle of claim 10, wherein: the electronic computing means (25) are connected to a sensor (36) adapted to measure the speed of rotation of the engine of the vehicle (2) to automatically determine the movement of the deflector (1) according to the threshold values of the speed of rotation stored in said memory (27, 28, 29).

16. The air intake assembly of a vehicle of claim 10, wherein: the electronic computing means (25) are connected to a sensor (37) suitable for measuring the temperature of the engine cooling liquid of the vehicle (2) to automatically determine the movement of the deflector (1) according to the threshold values of the temperature of the liquid stored in said memory (27, 28, 29).

17. The air intake assembly of a vehicle of claim 11, wherein: the electronic computing means (25) are connected to a sensor (38) adapted to measure the temperature of the air outside the vehicle (2) to automatically determine the movement of the deflector (1) according to the air temperature threshold values stored in said memory (27, 28, 29).

18. The air intake assembly of a vehicle of claim 10, wherein: the electronic calculation means (25) are adapted to measure the current entering the motor (19) and to signal, via the signalling means (33), if there is an abnormal movement of the deflector (1).

19. The air intake assembly of a vehicle of claim 10, wherein: the electronic computing means (25) is connected to a button (42) provided in the cab of the vehicle (2) for manually controlling the movement of the deflector (1).

20. An automobile (2), characterized in that: comprising one or more automotive air intake assembly according to any one of the preceding claims.