METHOD FOR CONTROLLING A MOTOR VEHICLE VENTILATION SYSTEM WITH MOTORIZED ADJUSTABLE VENTS

Abstract

Method for controlling an automated ventilation system for a motor vehicle passenger compartment, comprising at least one aerator (2) powered by an air blower (8), which is equipped with adjustable outlet vanes (4), for the same initial air flow rate demand delivered by the aerator (2), when the orientation of its vanes (4) is modified which increases the pressure drop of the aerator, it adjusts the operating characteristics of the blower (8) or it adds an additional air flow rate (24) into the passenger compartment delivered by an additional air vent, to increase the total air flow rate in the passenger compartment. Figure 2

Description

Title of the invention: METHOD FOR CONTROLLING A MOTOR VEHICLE VENTILATION SYSTEM WITH MOTORIZED ADJUSTABLE VENTS

[0001] The present invention relates to a method for controlling a motor vehicle ventilation system comprising motorized adjustable vents, as well as a motor vehicle equipped with a ventilation system implemented by such a control method.

[0002] Motor vehicles generally have air vents on the dashboard comprising flow direction fins, which deliver air cooled by an air conditioning device or heated by a heater in different directions. In particular, the driver can direct the flow towards his face or away from his face depending on his desired comfort, or towards other directions such as the windshield or the side windows, in particular to remove mist.

[0003] A known type of aerator, presented in particular by document FR-A1-3088856, comprises an elongated hollow body forming an air circulation vein, comprising inside two motorized flaps articulated along the same transverse axis passing through the diameter of the vein, each flap having, along a section plane perpendicular to the axis, an aerodynamic curved shape.

[0004] A motorization of the inclination of the shutters makes it possible to give these shutters different orientations which are dependent on each other. Optimizing the positions of the shutters provides air circulation on curved surfaces which makes it possible to ensure both an orientation of the flow at the outlet of the aerator, and a reduction in noise and pressure losses.

[0005] However, the aerators generally comprise an outlet grille formed by two perpendicular sets of fins, comprising for each set fins parallel to each other which can take different inclinations by tilting these fins or by tilting the complete aerator. It is thus possible, for example, by tilting a set of horizontal fins to direct the flow upwards, and for a set of vertical fins to direct the flow laterally.

[0006] Some aerators have an automatic motor which, depending on the driver's requests, provides different directions for the flow, in addition to adjusting the intensity of this flow and the temperature of the air delivered.

[0007] For an orientation of all the fins in a neutral position, aligned according to the direction of the flow arriving upstream, without deviation of this flow, the minimum occupation of the passage section by these fins is obtained, and the lowest pressure loss. For an increasing inclination of the fins, a greater deviation of the flow is obtained with a greater occupation of the passage section which increases the pressure loss.

[0008] In particular, for a high air flow rate of 100 kg / h, a pressure drop of approximately 100 Pa can be obtained with an aerator in the neutral position, whereas for a maximum deviation of the flow given by the greatest inclination of the fins, a pressure drop of approximately 300 Pa. This greater pressure drop leads to a reduction in the air flow in the passenger compartment, which then no longer conforms to the driver's initial demand. If the driver directs the air flow towards his face with a strong inclination of the aerators, he obtains a lower flow rate which does not ensure the required comfort.

[0009] The present invention aims in particular to avoid these problems of the prior art.

[0010] To this end, it proposes a method for controlling an automated ventilation system for a motor vehicle passenger compartment, comprising at least one aerator powered by an air blower, which is equipped with adjustable outlet vanes, this method being remarkable in that for the same initial air flow rate demand delivered by the aerator, when the orientation of its vanes is modified which increases the pressure drop of the aerator, it adjusts the operating characteristics of the blower or it adds an additional air flow rate into the passenger compartment delivered by an additional air vent, to increase the total air flow rate into the passenger compartment.

[0011] An advantage of this control method is that with a greater inclination of the fins giving a greater pressure drop at the outlet of the aerator, automatic regulation of the flow delivered into the passenger compartment is obtained to keep it constant, either with the same aerator by increasing the speed of its blower, or by adding an additional flow coming from another additional outlet which is activated, for example a windscreen defrosting vent.

[0012] This automatically maintains, in a simple and effective manner, without adding any component to an existing system, the initial air flow delivered despite a change in the direction of the air flow leaving the ventilator which is requested by the driver to ensure his comfort.

[0013] The method for controlling the automated ventilation system according to the invention may further comprise one or more of the following characteristics, which may be combined with each other.

[0014] According to one embodiment, the control method adjusts the operating characteristics of the blower by increasing its rotation speed.

[0015] In this case, the control method can increase the rotation speed of the blower so as to maintain the initial air flow in the same aerator.

[0016] Alternatively, the control method may adjust the operating characteristics. of the blower while respecting a maximum threshold of pressure loss through the aerator.

[0017] In this case, the control method can limit the maximum pressure drop threshold to 150Pa.

[0018] According to another embodiment, the control method adds an additional air flow into the passenger compartment delivered by the additional air vent to obtain the initial air flow in total.

[0019] Advantageously, the control method uses an additional air vent formed by a windshield defrost vent.

[0020] Advantageously, from information given by a motorization of the orientation of the fins, the control method automatically adjusts the operating characteristics of the blower or adds an additional air flow through an additional vent.

[0021] The invention also relates to a motor vehicle equipped with an automated ventilation system for its passenger compartment, remarkable in that it comprises a device for controlling this ventilation system having means implementing a control method comprising any one of the preceding characteristics.

[0022] In this case, advantageously the vehicle comprises a motorization of the fins delivering information to the means implementing the control method.

[0023] The invention will be better understood and other characteristics and advantages will appear more clearly on reading the description below given by way of example, with reference to the appended drawings in which:

[0024] [Fig-1] is a sectional diagram of the air stream of an aeration system implemented by a control method according to the invention, showing the fins of the aerator in the neutral position;

[0025] [Fig.2] is a diagram of this air stream showing the fins in the maximum inclination position requested by the driver; and

[0026] [Fig.3] is a graph showing examples of different pressure losses as a function of air flow rates delivered by this aerator.

[0027] [Fig.l] shows an aerator 2 with adjustable vanes 4 thanks to a motor 10, arranged at the upper end of an air stream 6 comprising upstream a blower 8 which receives air cooled by an air conditioning device or heated by a heating system, to deliver it into the passenger compartment of the vehicle, in front of the driver 12.

[0028] The evolution of motor vehicles for certain models gives the dashboard a reduced size in the longitudinal direction of the vehicle, reducing the depth, which requires modifying the positioning of the air vents 2.

[0029] In particular, the air vents 2 fixed to the dashboard of the vehicle, below the windshield, may have installation constraints giving poor access. sibility of adjustments of the fins 4 by the driver. To remedy this, manufacturers install a motorization 10 for the inclination of the fins 4 of the aerators 2 in order to avoid the driver having to perform a delicate maneuver to access them and adjust them manually.

[0030] The fins 4 presented in their neutral position, not deflecting the air flow, give an orientation of this flow generally passing above the head of the conductor 12, with a minimum obstruction of the outlet of the vein 6 and a low pressure loss when passing the aerator 2. For the same speed of the blower 8 the air flow is maximum.

[0031] [Fig.2] shows, following a request from the driver 12, a maximum orientation of the fins 4 actuated by the motorization 10, giving a lowering of the flow of air delivered to direct it towards his face.

[0032] In this case, a reduction in the flow passage section in the aerator 2 is obtained as well as a less good aerodynamic profile because of the inclination of the fins 4 disturbing this passage, which cause a pressure loss reducing the flow rate for a speed of the blower 8 remaining identical.

[0033] [Fig.3] shows, as a function of the air flow rate DA in kg / h indicated on the horizontal axis, the pressure loss PdC in Pa caused by the aerator 2, which in all cases increases with the flow rate.

[0034] In a first operating case for an aerator 2 in the neutral position presented [Fig.l], with a flow passing above the conductor 12, the pressure drop is indicated by the first lower curve 20. In this case we have a pressure drop which is at its lowest and the maximum flow rate, with for an air flow rate of 100kg / h a first operating point A showing a low level of pressure drop which is 100Pa.

[0035] In a second operating case for an aerator 2 with its maximum inclination of the fins 4, presented [Fig.2], allowing the driver 12 to receive the air flow facing his face, there is a much higher pressure loss indicated by the second higher curve 22, including for the same flow rate the second operating point B of 300Pa.

[0036] If we want to respect a maximum pressure drop of less than 150Pa, for example 100Pa, in particular to limit the noise and energy consumption of the blower 8, we then obtain a third operating point C on the second curve 22 with a reduced air flow of 80kg / h.

[0037] According to a first mode of operation of the method, when the driver requests from the ventilation system a maximum inclination of the fins 4 of the aerator 2, carried out by their motorization 10, this method then automatically increases the speed of the blower 8 to compensate for the loss of load and restore the initial air flow. In the example presented the process comes to the second operating point B, and then maintains the requested air flow which is 100 kg / h.

[0038] According to a second mode of operation of the method for the same driver request, in order to respect a maximum pressure drop of 100 Pa, the speed of the blower 8 is little modified with an air flow rate from the ventilator 2 which drops to 80 kg / h. In this case, the windscreen defrosting vent arranged on the dashboard is advantageously used, with an adjustment of its flow giving an additional flow rate 24 of 20 kg / h in order to obtain the total requested ventilation flow rate of 100 kg / h.

[0039] Advantageously, information coming from the motorization 10 of the fins 4 is used to know their positions, and to automatically implement a method control mode.

[0040] This provides, in a simple manner, without modification of the existing ventilation system, and without additional cost, with only programming taking into account the position of the fins 4 of the aerator 2, improved comfort by maintaining the air flow constantly without the driver having to intervene.

Claims

Claims

1. Method for controlling an automated ventilation system for a motor vehicle passenger compartment, comprising at least one aerator (2) powered by an air blower (8), which is equipped with adjustable outlet vanes (4), characterized in that for the same initial air flow rate demand delivered by the aerator (2), when the orientation of its vanes (4) is modified which increases the pressure drop of the aerator (PdC), it adjusts the operating characteristics of the blower (8) or it adds an additional air flow rate (24) into the passenger compartment delivered by an additional air vent, to increase the total air flow rate in the passenger compartment (DA).

2. Control method according to claim 1, characterized in that it adjusts the operating characteristics of the blower (8) by increasing its rotation speed.

3. Control method according to claim 2, characterized in that it increases the rotation speed of the blower (8) so as to maintain the initial air flow in the same aerator (2).

4. Control method according to any one of the preceding claims, characterized in that it adjusts the operating characteristics of the blower (8) while respecting a maximum pressure drop threshold (PdC) through the aerator (2).

5. Control method according to claim 4, characterized in that it limits the maximum pressure drop threshold (PdC) to 150Pa.

6. Control method according to any one of the preceding claims, characterized in that it adds a complementary air flow (24) into the passenger compartment delivered by the additional air vent to obtain the total initial air flow.

7. Control method according to any one of the preceding claims, characterized in that it uses an additional air vent formed by a windshield defrosting vent.

8. Control method according to any one of the preceding claims, characterized in that from information given by a motorization (10) of the orientation of the fins (4), it automatically adjusts the operating characteristics of the blower (8) or adds an additional air flow (24) through an additional vent.

9. Motor vehicle equipped with an automated ventilation system for its passenger compartment, characterized in that it comprises a device for controlling this ventilation system having means implementing a method control according to any one of the preceding claims.

10. Motor vehicle according to claim 9, characterized in that it comprises a motorization (10) of the fins (4) delivering information to the means implementing the control method.

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