Anti-aquaplaning system for automobiles and related methods

Abstract

Disclosed herein is an aquaplaning prevention system (1) for a motor vehicle, comprising: a storage unit (2) for a working fluid; a supply unit (6); a dispensing unit (8), said dispensing unit (8) having at least first and second injectors (10, 12) configured to inject liquid towards the ground at positions in front of the right (RT) and left (LT) treads of right (R) and left (L) wheels of an axle of the motor vehicle, respectively, and at least one fluid accumulator (14) configured to store liquid under pressure and in fluid communication with said first injector (10) and second injector (12).

Description

[Technical field]

[0001] [Description Text] The present invention relates to an anti-aquaplaning system for motor vehicles, in particular it has been developed for an anti-aquaplaning system based on the injection of liquid towards the front of the tread. [Background technology]

[0002] As is commonly known, aquaplaning is an event that can occur when a moving vehicle encounters an extensive layer of water on the road surface, which is so abundant that the wheels of the vehicle cannot properly adhere to the road surface. Thus, in such a situation, the wheels float and / or slip on the wet road surface, resulting in loss of tire adhesion.

[0003] In order to reduce the risks arising from such events, the Applicant has already developed various technical solutions, including for example the solutions described in Italian patent applications no. 102014902296915 and no. 102021000011117, both relating to industrial inventions in the name of the same Applicant.

[0004] The solution described in the former document involves the use of an injection device associated with at least one vehicle wheel and adapted to generate a jet of high pressure fluid onto the wet road surface in front of the tread of the vehicle wheel, while the solution described in the latter document envisages a hydraulic supply unit which pressurizes the supply circuit of the injector to a high pressure level to generate a fluid jet with a high injection pressure, ensuring particularly fast intervention times.

[0005] These properties of the known system are also the source of its main technical problems: pressurizing the injector supply circuits to high pressure values ​​in order to ensure a particularly rapid intervention of the system necessarily involves the use of hydraulic supply units, in particular hydraulic pumps, which require high power consumption for operation and therefore for connection to high-performance electric motors, and are therefore very bulky, heavy and expensive. These characteristics ultimately make their installation in the vehicle extremely difficult.

[0006] [Objective of the Invention] The present invention aims to solve the technical problems outlined above. In particular, it aims to provide an anti-aquaplaning system for motor vehicles, adapted to guarantee a performance equal to or better than known systems in terms of injection pressure and rapidity of intervention, but without the aforementioned problems in terms of weight, cost and bulkiness. Furthermore, the present invention aims to increase the multifunctionality of the anti-aquaplaning system by expanding its range of use on board the vehicle. Summary of the Invention

[0007] The object of the invention is achieved by a system and method having the features set forth in the following claims, which form an integral part of the technical teachings provided herein on the invention. [Brief description of the drawings]

[0008] The invention will now be described with reference to the accompanying drawings, which are provided purely as non-limiting examples. [Figure 1] 1 is a schematic representation of an anti-aquaplaning system according to the present invention. [Diagram 2] 1 is a functional representation of an anti-aquaplaning system according to the present invention. [Diagram 3] FIG. 1 shows a schematic layout of an anti-aquaplaning system according to the invention mounted on a vehicle; [Figure 4]FIG. 2 is a state diagram of a system in accordance with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Reference number 1 in FIG. 1 indicates as a whole an anti-aquaplaning system for motor vehicles according to a first embodiment of the invention.

[0010] In this and other embodiments, the system 1 includes: 2 storage units for operating fluid, Mixing unit 4, Supply unit 6, a dispensing unit 8, which comprises at least a first and a second injector 10, 12 and at least one (pressurized) fluid accumulator 14 in fluid communication with the injectors 10, 12; These injectors are configured to inject liquid towards the ground at a position in front of the right tread RT of the right wheel R and the left tread LT of the left wheel R of the axle of the vehicle. The fluid communication between the accumulator 14 and the injectors 10, 12 is regulated by means of a flow control element comprising a first valve V10 and a second valve V12 arranged upstream of the injectors 10 and 12, respectively. In other embodiments, the presence of an accumulator associated with each injector 10, 12 and placed immediately upstream of the corresponding valve V10, V12 may be envisaged.

[0011] In general, the dispensing unit 8 may be installed on any axle of the vehicle (on the front axle, or on the rear axle, or on both); thus, installation on the rear axle is also possible, i.e. the first and second injectors 10, 12 may be configured to inject liquid towards the ground at a position in front of the rear axle of the vehicle and / or the right tread of the right wheel and the left tread of the left wheel of the front axle of the vehicle, respectively. This can be done regardless of the number of accumulators 14 mounted on the system 1.

[0012] The storage unit 2 comprises a main reservoir 16 configured to store a corresponding main working fluid and at least one auxiliary reservoir 17 configured to store a corresponding auxiliary working fluid, in particular a foam inhibitor, configured to mix with the main working fluid. In a preferred embodiment, the main reservoir 16 is selected to be a reservoir for a windscreen washer fluid (water and detergent) of an automobile.

[0013] The mixing unit 4 comprises a manifold IM (or intake manifold) hydraulically and respectively connected to a main reservoir 16 and an auxiliary reservoir 17. In particular, the manifold IM receives the following hydraulic connections: Hydraulic connection 18 for main reservoir 16 · Hydraulic connection 20 for auxiliary reservoir 17.

[0014] The mixing unit 6 also comprises an electromotive valve V17 for the auxiliary reservoir 17, which is in particular arranged at the hydraulic connection 20 of the auxiliary reservoir 17 and which is actuated by a drive signal S17.

[0015] The motorized valve V17 is configured to selectively allow the auxiliary operating fluid to transfer from the auxiliary reservoir 17 to the manifold IM, such that the motorized valve V17 can be operated to assume a closed position, thereby preventing the transfer, or an open position, thereby allowing the transfer.

[0016] It must be noted, however, that the mixing unit 4 can be omitted altogether by providing a premixed solution. In other words, it is possible to envisage an embodiment in which the storage unit 2 only comprises a reservoir 16 for storing the windscreen washer solution (water and washer fluid) mixed with a defoamer. In such a case, the mixture of the working fluid has a fixed and unalterable composition.

[0017] The supply unit 6 comprises a pump 22 which includes an inlet port 24 and a delivery port 26. In a preferred embodiment, the pump 22 is provided with (preferably three) radial pumping elements.

[0018] Upstream of the inlet port (but downstream of the junction of hydraulic connection 20 with manifold IM) is provided a one-way inlet valve V24, while downstream of the delivery port 26 (but upstream of accumulator 14) is provided a one-way delivery valve V26. Both valves V24 and V26 only allow hydraulic flow in the direction corresponding to operation; thus, valve V24 allows transition from manifold IM towards delivery port V24, while valve V26 only allows transition out of port 26.

[0019] 1, it can be observed that the manifold IM and its associated reservoirs 16, 17 are hydraulically connected to the inlet port 24 of the pump 22. For the auxiliary reservoir, the hydraulic connection is active when the valve V17 is in the open position, whereas the main reservoir 16 is in a situation where the hydraulic connection is always active.

[0020] Valve V17 is therefore configured to selectively enable the transfer of auxiliary working fluid at hydraulic connection 20 between auxiliary reservoir 17 and collector IM to allow mixing of the main working fluid coming from reservoir 16 with the auxiliary working fluid, thereby defining a working fluid mixture of the system. Note that the working fluid mixture may comprise only reservoir 16 liquid (i.e. a mixture of 100% 16 and 0% 17) or a mixture of reservoir 16 and reservoir 17 liquid.

[0021] A delivery port 26 of the pump 22 is hydraulically connected to a manifold DM (ie, a delivery manifold), which is connected to a wash manifold 28 , the accumulator 14 , and the injectors 10 and 12 .

[0022] More specifically, it is possible to see three circuit junctions on the manifold DM, in particular: a junction J28, through which the manifold 28 establishes fluid communication with the manifold DM through a hydraulic connection 30 (preferably with a pressure reducing device 31 arranged therein); an electromotive valve V28 is arranged at the hydraulic connection 30 between the manifold 28 and the junction J28 and is actuated by an actuation signal S28. The electromotive valve V28 is configured to selectively allow the mixture of working liquids to migrate from the manifold DM towards the manifold 28, i.e. the electromotive valve V28 can be controlled to assume a closed position, in which migration is disabled, and an open position, in which migration is enabled; · a junction J14 where the accumulator 14 establishes fluid communication with the manifold DM; · Junction J8, where the injectors 10 and 12 establish fluid communication with the manifold DM. Valves V10 and V12 are disposed between junction J8 and each of the injectors 10 and 12.

[0023] Junction J28 is preferably located hydraulically upstream of junction J14, which in turn is located hydraulically upstream of junction J8. However, junction J28 may be located downstream of junction J14 while junction J14 remains located upstream of junction J8. All of junctions J28, J14, and J6 are located hydraulically downstream of valve V26.

[0024] However, it should be noted that the configuration of user devices connected to the manifold DM may vary depending on the embodiment, in particular depending on the number of accumulators 14 and the number of flow control elements that manage the transition of the mixture of working liquid in fluid communication between the accumulators 14 and the injectors 10, 12.

[0025] Specifically, the embodiment can exhibit at least three alternative configurations, namely: a single fluid accumulator 14 in fluid communication with the first injector 10 and the second injector 12 (as previously described), where the single fluid accumulator 14 is connected to the delivery manifold DM at junction J14, the first injector 10 and the second injector 12 are connected to the delivery manifold DM at junction J8 located downstream of junction J14, a first flow control element (valve V10) is hydraulically disposed between junction J8 and the first injector 10, and a second flow control element (valve V12) is hydraulically disposed between junction J8 and the second injector 12 a single fluid accumulator 14 in fluid communication with the first injector 10 and the second injector 12, where the single fluid accumulator 14 is connected to the delivery manifold DM at junction J14, the first injector 10 and the second injector 12 are connected to the delivery manifold DM at junction J8 located downstream of junction J14, and a single flow control element (similar to valves V10 and V12) is hydraulically located between junction J14 and junction J8; in this embodiment, injection of liquid through the injectors 10, 12 is controlled by opening and closing the single flow control element; a first fluid accumulator 14 in fluid communication with the first injector 10, and a second fluid accumulator 14 in fluid communication with the second injector 12, where a first flow control element (valve V10) is hydraulically disposed between the first fluid accumulator 14 and the first injector 10, and a second flow control element (valve V12) is hydraulically disposed between the second fluid accumulator 14 and the second injector 12; in this embodiment, both fluid accumulators are connected to the delivery manifold DM at a single junction corresponding to junction J8, while junction J14 is omitted (junction J28 is maintained and disposed upstream of junction J14). A number of wash fluid pressure lines 32, 34, 36, 38, 40, 42 branch off from the wash manifold 28, each equipped with an electrically actuated valve V32, V34, V36, V38, V40, V42, respectively, configured to enable and disable the transfer of fluid from the manifold 28 (by being moved between open and closed positions in the same manner as other valves in the system). Each wash fluid pressure line connects the manifold 28 to a corresponding wash device configured to dispense a mixture of operating fluid to a corresponding sensor or vehicle equipment to clean it. As an example, the line 32 may connect the manifold 28 to one or more windshield washer nozzles, the line 34 may connect the manifold 28 to one or more (typically two) nozzles for cleaning a medium-range radar, the line 36 may connect the manifold 28 to one or more nozzles for cleaning a long-range radar, the line 38 may connect the collector 28 to one or more nozzles for cleaning a LiDAR device, the line 40 may connect the collector 28 to one or more (typically two) nozzles for cleaning a ball camera, and the line 42 may connect the manifold 28 to one or more nozzles for cleaning a rear camera. Of course, the number of hydraulic lines connected to the manifold 28 may vary depending on the user device to be supplied and may therefore be less or more than described in the above example.

[0026] The supply unit 6 is therefore configured to draw a mixture of working fluids from the manifold IM via the inlet port 24 for delivery to the manifold 28, the accumulator 14 and the injectors 10, 12. However, as will be seen below, providing liquid directly from the pump 22 to the injectors 10, 12 is not the solution generally adopted in the present invention.

[0027] FIG. 3 shows an example layout of system 1 in a vehicle V, with which the hydraulic lines and components of system 1 are associated devices of vehicle V, in particular: - front windshield washer nozzle 132 (line 32; of course it is possible to branch off the hydraulic line 32 to dispense liquid also to the rear windshield); · A pair of medium-range radars 134 (line 34); · Long-range radar 136 (line 36); · LiDAR138 (line 38); · A pair of ball cameras 140 (line 40); Rear camera 142 (line 42) The location is also shown.

[0028] Reference numerals 144 and 146 denote a stereoscopic camera and a driver's seat camera, respectively, which are positioned behind the vehicle's windshield and therefore subject to cleaning / washing when the windshield washer nozzle 132 is activated.

[0029] Figure 2 shows a functional diagram of the system 1 according to the invention, where the structure of the system circuit is simplified for clarity of illustration, and where it is possible to see the control section CS which drives the motorized valves and pump 22 of the system 1. As mentioned before, for the sake of simplicity, only the valves V10, V12 and V28 are shown in the form of functional blocks in the figure, but a similar representation to the valves V10, V12 and V28 can be assumed for the valves V32 to V42, although they are not shown. The components already described with reference to figure 1 are indicated by the same reference numbers.

[0030] The control section CS comprises a driver D10 for valve V10, a driver D12 for valve V12 and a driver D28 for valve V28. The control section further comprises a driver / control unit E22 for an electric motor M22 which operates the pump 22. All circuits / units within the control section CS are powered by a power supply VS (typically a 12V CC supply) which is common to valves V10, V12, V28 and possibly additional valves V32-V42.

[0031] The control section CS is logically dependent on an overall control unit CU of the system. The unit CU is operatively connected to the vehicle's CAN network CNW, so that the unit CU can receive in real time data from the vehicle's attitude sensors (to activate the injectors 10, 12), but also from the vehicle's sensors and equipment involved in driving assistance and more generally, whose washing and cleaning is assisted by hydraulic lines branching off from the manifold 28. The overall control unit CU is operatively connected (at the output to the circuits D10, D12 and D28 and at the input / output to the circuit E22) and is further operatively connected (at the input) to a level sensor LS16 arranged to detect the liquid level in the reservoir 16, and to a pressure sensor PS14 mounted on the manifold DM, in particular at a position between the junctions J14 and J8. The manifold DM is further provided with a pressure relief valve RV, preferably arranged at a position between the junction J8 and the pressure sensor PS14.

[0032] Pressure sensor PS14 is configured to detect the fluid pressure in accumulator 14 and therefore in the hydraulic line upstream of valves V10 and V12, while valve RV is configured to discharge fluid to the environment when a threshold pressure is exceeded; such threshold pressure is selected to maintain the structural integrity of the components of system 1.

[0033] System 1 works as follows:

[0034] At a schematic level, the system 1 implements the operation of the supply unit 6, specifically the pump 22, according to a filling cycle, in contrast to known systems, rather than following an operation limited to the intervention of the system 1.

[0035] The pump 22 operates primarily according to the readings of the sensor PS14, i.e. in response to the pressure upstream of the injectors 10, 12, in the manifold DM and thus in the accumulator 14. Secondary control signals for the pump 22 relate to the opening or closing of the valves V32-V42.

[0036] More specifically, thanks to the mixing unit 4 it is possible to define a mixture of the operating liquid of the system 1 for filling the accumulator 14, or a number of accumulators 14 if more than one is present.

[0037] The system's operating fluid mixture mainly comprises a windshield washer solution (water and windshield washer fluid) stored in reservoir 16, and a mixture of antifoam agent stored in reservoir 17. The antifoam agent is combined with the windshield washer solution coming from reservoir 16 by opening valve V17 and introducing it into the liquid stream moving through manifold IM during intake via port 26.

[0038] The mixture of working fluid delivered by pump 22 via delivery port 24 gradually fills the circuit section downstream of delivery port 26, thereby charging accumulators 14. In a manner known per se, each accumulator 14 fills with fluid whilst the pressure gradually increases due to compression of dead spaces, typically filled with an inert gas.

[0039] While the accumulator 14 is being charged, valve V28 is generally kept closed and valves V10 and V12 are always kept closed. Thus, the delivery pressure at port 26 is determined solely by the charging of the accumulator 14. Operation of pump 22 is stopped when the reading of sensor PS14 indicates that the maximum charging pressure envisaged in system 1 has been reached, which is determined based on the operating requirements of injectors 10, 12, i.e. the requirements of the anti-aquaplaning intervention of system 1. Pressure relief valve RV prevents pressure overload of system 1.

[0040] At the end of filling the accumulator 14, the pump 22 is stopped and the circuit section downstream of its delivery (essentially the manifold DM and all user devices connected thereto at junctions J28, J14, J8) statically contains a pressurized mixture of the working fluid of the system 1 at the maximum filling pressure.

[0041] When an intervention of the anti-aquaplaning system 1 is required, based on data coming from the vehicle's CAN network CNW and from the resulting control sent by the control unit CU to the drivers V10 and V12, the valves V10 and V12 are switched to the open position for a predetermined time during which a jet of liquid (mixture of working liquids) is dispensed towards a position in front of the treads RT and LT of the vehicle V. During the injection of the liquid, the injection pressure is reduced from a maximum value at the beginning of the intervention (e.g. 140 bar (14 Mpa), maximum filling pressure) to a value at the end of the intervention (e.g. 60 bar (6 MPa)). Then, at the end of the intervention, the valves V10, V12 are returned to the closed position and the pump 22 is restarted, since the sensor PS detects a pressure in the manifold DM that is not compatible with the operation of the anti-aquaplaning system. It must be noted that the system is generally adjusted so that the pressure at the end of the intervention causes a new start of the motor M22 of the pump 22.

[0042] When no anti-aquaplaning intervention is required, the system 1 can perform a distributed, on-demand cleaning of the devices or equipment 132-146 on board the vehicle V. In this regard, the mixture of working fluid statically pressurized in the manifold DM is also available to the manifold 28 and is ready to supply the hydraulic lines 32-42. However, each of these hydraulic lines requires a pressurized fluid at a value definitely lower than the operating pressure of the injectors 10, 12. For this purpose, when the valve V28 is opened, the pressure reducing device 31 rapidly reduces the pressure upstream of the manifold 28 to a value compatible with the operation of the cleaning nozzles at the ends of the lines 32-42. The valves V32-V34 therefore operate with a fluid having a lower pressure than in the valves V28 and V10, V12. Each user device connected to the lines 32-42 can be controlled independently of the other user devices, simply by switching the respective valve to the open position and on the condition that the manifold 28 contains a mixture of working fluid pressurized at a value suitable for operation. In this regard, a situation may arise in which an intervention of the anti-aquaplaning system (i.e. injection via the injectors 10, 12) is performed simultaneously with a cleaning event of a device or equipment 132-146 installed on the vehicle 1. At the same time, however, the pump 22 may start a new start to recharge the accumulator 14; in order not to jeopardize the normal cleaning of the device or equipment 132-146, it is possible to start the pump 22 while leaving open the valve V28 and one or more of the valves V32-V34, thus supplying the manifold 28 and the active hydraulic lines 32-34 with a mixture of working fluid drawn directly from the delivery of the pump 22.

[0043] In such a case, since antifoam is not necessarily required for the supply of the hydraulic lines 32-42, it is possible to temporarily disable the intake of antifoam from the reservoir 17 during the direct supply to the manifold 28; at the end of the cleaning operation, the valve V28 (and therewith the valves of the set V32-V42 that were active until now) is returned to the closed position and it is possible to restore the intake of antifoam by newly opening the valve V17 and thus a new filling of the system according to the readings of the sensor PS14. Only when the liquid level in the reservoir 16 becomes insufficient, the readings of the sensor LS16 determine the operation of the system. In such a case, if the accumulator 14 is filled, the unit CU issues a general danger warning, whereas if it remains deficient or if the anti-aquaplaning system is activated again, the unit CU sends an error signal due to the impossibility of refilling the accumulator 14, thereby indicating that the anti-aquaplaning intervention is not available.

[0044] Thus, in general, the transfer of the mixture of working fluid from the delivery manifold DM to the washing manifold 28 is possible both when the supply unit 6 (motor M22-pump 22) is active (or has started to start) and when the supply unit 6 (motor M22-pump 22) is not active. In both cases, the transfer of the mixture of working fluid in fluid communication between the at least one fluid accumulator 14 and the injectors 10, 12 remains disabled (so that no parallel processing occurs with the intervention of the anti-aquaplaning system 1 with the injection of liquid via the injectors 10, 12).

[0045] 4 summarizes in a state diagram 200 the operating modes of the system 1 according to the invention described above. In particular, the system 1 includes four operating states: an inactive state I (system 1 is not functioning), corresponding to a stopped state of the supply unit 6 and a standby state of the dispensing unit 8, in particular the standby state of the injectors 10, 12; · active state A, corresponding to the intervention of the anti-aquaplaning system 1 with the injection of liquid by means of the injectors 10, 12; a refill state R, which corresponds to a situation in which the supply unit 6 has been activated in order to restore the supply of the mixture of working fluids to the accumulator 14, but which may also correspond to a situation in which the activation of the supply unit 6 is intended to supply directly to the cleaning manifold 28 for cleaning the devices and equipment installed on the vehicle V; A fault condition F corresponding to a condition in which one or more components of the system 1 are in a fault condition or are otherwise in a condition that does not match the overall condition of the vehicle V.

[0046] Reference numerals 202-214 describe the possible evolution of system 1 through states I, A, R, F, and further illustrate how the evolution between states is not always bidirectional. Specifically, system 1 is configured to transition bidirectionally (entry-exit) from state I to state A and from state I to state R, but all transitions to state F are unidirectional towards state F itself. In other words, once the system transitions to fault state F, the system is not configured to autonomously exit such state without an external reset intervention. This safety measure is implemented due to the nature of anti-aquaplaning system 1 being critical with respect to the safety of vehicle V.

[0047] The transitions from state I to state A are associated with references 202 (I to A) and 204 (A to I). Transition 202 corresponds to the intervention of the anti-aquaplaning system 1 with the injection of liquid via the injectors 10, 12. Transition 204 corresponds to the end of the intervention of said system 1 due to the absence of the aquaplaning triggering conditions (e.g. the vehicle V passing through a puddle that was generating an aquaplaning event) or due to a pressure drop of the mixture of working liquid in the accumulator 14 below a minimum value.

[0048] The transitions from state I to state R are associated with reference signs 206 (I to R) and 208 (R to I). Transition 206 corresponds to the (re)activation of the supply unit 6 for recharging the accumulator 14 after the intervention of the anti-aquaplaning system 1. In this respect, transition 206 corresponds to the development of transition 204. Furthermore, transition 206 may represent the situation of the system 1 when the flushing manifold 28 is directly supplied while recharging the accumulator 14. Transition 208 corresponds to the achievement of the filled accumulator 14 situation and the subsequent shut-down of the supply unit 6.

[0049] Transitions 210, 212 and 214 correspond to cases of system failure at various levels. Transition 210 represents a failure occurring in the inactive system 1, for example a break in the motor M22 of the pump 22 or an abnormality in the drive circuits D10, D12, D28, which may jeopardize the intervention of the anti-aquaplaning system or the cleaning of sensors / instruments on board the vehicle V. Another event that may lead to transition 210 is the depletion of liquid in the reservoir 16.

[0050] The transition 212 is made in case of failure of the dosing unit 8, for example during the intervention of the anti-aquaplaning system, specifically in case of failure of the valves V10, V12. This may include the failure of the valves to open despite the drivers D10, D12 being fully effective, or the unexpected closure of one or more of the valves V10, V12 during injection (the number depends on the valve / accumulator configuration as described above).

[0051] Finally, transition 214 is performed when recharging of one or more accumulators is not successful, for example in the case of failure or overload of motor M22, if motor M22 cannot be stopped when the charging pressure is reached (by intervention of valve RV), if the liquid level in reservoir 16 falls below a minimum safe amount or below the amount required to complete the recharging, or if the charging pressure cannot be reached after a predetermined time, revealing a liquid leak in system 1.

[0052] The effectiveness of a liquid jet aquaplaning prevention system such as system 1 depends on various physical and geometric factors that characterize the liquid jet emitted by the injectors 10, 12. These factors include the liquid injection pressure, which must generally be maintained between a maximum (e.g., 150 bar (15 MPa)) and a minimum (e.g., 60 bar (6 MPa)) value during jet dispensing, the amount of fluid delivered in time (i.e., the flow rate of each injector, e.g., 9 l / min per injector), the minimum jet duration (e.g., 3 seconds), and the rapidity of jet initiation, i.e., the maximum time required to produce a jet having the aforementioned characteristics (e.g., less than 100 ms).

[0053] In known systems, such as that described in patent application no. 102021000011117 in the name of the same applicant, an electric pump generates the required fluid flow directly, without accumulation or recharging of the system. The aforementioned physical factors therefore determine the size of the pump, its power consumption, and ultimately its weight and cost. Based on the required flow rate and jet duration, it is possible to determine the internal volume of the pumping element of the piston pump. Furthermore, it is possible to determine the required compression force, i.e. the required work, and, if the start-up time is known, it is possible to determine the power required to compress the fluid to the required pressure.

[0054] Finally, from this value and the required start-up agility it is possible to determine the sizing of the electric motor adapted to operate the pumping element, and by determining the current intensity value the optimum voltage that must be supplied to the electric motor is further determined.

[0055] Also by way of example, the anti-aquaplaning system described in patent application no. 102021000011117, which dispenses jets with an average flow rate of 9 l / min per injector at an average pressure of 90 bar (9 MPa) for a jet duration of 1.5 seconds, comprises an electric motor with a supply voltage of 48 V and an approximate power of 5 Kw (approximately 10 dm 3The present invention requires a pump unit having an approximate size of 400mm x 200mm x 200mm (with a volume of 1000 sq. m) and weighing 35kg (if it were made of aluminium).

[0056] In the present invention, the physical factors characterizing the fluid jet for anti-aquaplaning operation described above are ensured by accumulating a fluid in an accumulator 14, a preferred but not exclusive embodiment of which involves compression of an inert gas (e.g. nitrogen) in a dead space by the movement of the fluid against an elastic membrane or piston that separates the fluid from the gas.

[0057] As an example, a gas accumulator 14 containing the amount of liquid required to ensure a jet of 3.5 seconds duration (approximately 1.3 liters) would start at a maximum pressure of 140 bar (14 MPa) and drain down to a minimum pressure of 60 bar (6 MPa), while ensuring a flow rate of 9 l / min per injector 10, 12, and when made of steel would have a diameter of approximately 6 dm 3 It has a size of about 275mm x 166mm x 166mm (with a total volume of about 1.0kg) and a weight of about 8Kg (which may be reduced by a factor of 0.6 in embodiments including composite materials).

[0058] Furthermore, it should be noted that the amount of accumulated liquid can be divided into several accumulators 14 (for example, two as shown in FIG. 3; in the case of two or more accumulators, they are all identical), thus simplifying their installation in the engine compartment of the vehicle V.

[0059] As mentioned above, the operation of the pump 22 according to the invention is not affected by the delivery of liquid during the intervention of the anti-aquaplaning system 1: this event is effected only by the draining of the accumulators and the switching of the valves V10, V12 to the open position.

[0060] The physical factors regarding the sizing of the pump and the associated electric motor may therefore be modified with respect to the known techniques described above; in particular, it is no longer necessary to guarantee the amount of flow rate mentioned thus far, since instead it is possible to extend the refill time of the accumulator 14, if necessary, after the intervention of the anti-aquaplaning system 1 by draining the accumulator by injection via the injectors 10, 12.

[0061] As an example, if we assume that the refill time of the accumulator 14 amounts to 6 minutes, then for an accumulator or accumulators having the characteristics described above, it is sufficient to guarantee a flow rate of 0.21 l / min.

[0062] It must be noted that, during a refill event, such flow rate may also satisfy possible fluid requirements of one or more user devices connected to the manifold 28 described with reference to Fig. 3 when such devices require cleaning. Thus, in general, according to the invention, the supply unit 6 may directly supply the manifold 28 and the user devices associated therewith, but not the injectors 10, 12, as such flow rate would in any case be insufficient to ensure effective intervention of the anti-aquaplaning system (as mentioned above, the supply to the injectors 10, 12, and therefore the intervention event of the anti-aquaplaning system, is performed by the accumulator 14).

[0063] On this basis, it is therefore possible to size the pump 22 and the electric motor M22 starting from the above flow values, imposing a maximum refill pressure of the accumulator 14 equal to 140 bar (14 MPa), resulting in a size of approximately 200 mm x 200 mm x 100 mm, approximately 1.7 dm 3 and a weight of about 6 Kg. In this example, the motor M22 has a power of about 0.4 Kw and a supply voltage of 12 V.

[0064] In addition to the advantages previously enumerated with regard to power requirements, weight and volume of components, another advantage is that the control circuit E22 of the pump 22 is simplified, since it is no longer necessary to assume stepwise control of the electric motor M22 simultaneously with the opening signals of the valves V10, V12, as is the case in the solution proposed by patent application No. 102021000011117.

[0065] This solution actually requires aligning the position of the pump piston to control its push stroke, damping its movement according to the fluid dispense and according to the associated opening of the valve upstream of the injector, and performing a diversion stroke of the piston to refill the liquid required at the later start-up. In other words, the position of the pump piston and its overall movement must be in phase with the events of the intervention of the anti-aquaplaning system. Moreover, this imposes constraints on the choice of pump type by essentially limiting such a choice to single piston solutions with stepped control.

[0066] In the case of the present invention, this is not necessary: ​​the activation of the motor M22 and the pump 22 and the opening control of the valves V10, V12 can be completely independent, which ensures that the number of control parameters required is reduced. This can be clearly seen in the diagram of Fig. 2: the activation of the pump 22 essentially depends on the readings of the sensor PS14. In this respect, moreover, it is possible to choose a simpler pump among a wider range of possibilities, since the number, type and movement of the pumping elements are not part of the control chain.

[0067] Another advantage of the present invention is the availability of liquid under pressure that can be used at any time to clean various sensors or instruments 132-146 that may be present in autonomous vehicles at various levels. In current implementations, there are many such sensors (four to eight, including radar, cameras, and LiDAR for Level 2-3 or higher levels of autonomy), which require a self-cleaning system when their detection capabilities are limited by dust, mud, or snow, and the self-cleaning must be controlled independently for each sensor in order not to limit the overall detection performance of the system.

[0068] Thanks to the individual control of the valves V32 to V42, each user device connected thereto can be controlled separately, as required, depending on the filling state of the accumulator 14 and on the amount of liquid required for cleaning (which depends on the type of sensor and the amount of soiling present), and it also makes it possible to choose between drawing liquid from the accumulator (14) and drawing it directly from the pump delivery (and thus from the reservoirs 16, 17), i.e. this makes it possible, inter alia, to avoid the assumption of several small low-pressure pumps for supplying the respective hydraulic lines.

[0069] Naturally, implementation details and embodiments may vary significantly from what has been described and illustrated above without departing from the scope of the invention as defined in the appended claims.

Claims

1. 1. An anti-aquaplaning system for a motor vehicle, comprising: Storage unit for operating fluid Supply unit ・Dispensing unit Equipped with the dispensing unit comprises at least a first injector and a second injector configured to inject liquid towards the ground at a location forward of a right tread (RT) of a right wheel (R) and a left tread (LT) of a left wheel (L) of an axle of the vehicle, respectively, and at least one fluid accumulator configured to store liquid under pressure and in fluid communication with the first injector and the second injector; the supply unit is configured to draw a working fluid mixture from the storage unit and deliver the working fluid mixture to the at least one fluid accumulator; 1. An anti-aquaplaning system, wherein the dispensing unit has at least one flow control element configured to enable a flow of the working fluid mixture in fluid communication between the at least one fluid accumulator and the first and second injectors in the event of an intervention of the anti-aquaplaning system including injection of liquid using the first and second injectors, and configured to disable a flow of the working fluid mixture in fluid communication between the at least one fluid accumulator and the first and second injectors in order to fill the fluid accumulator with the working fluid mixture.

2. the supply unit includes a pump having an inlet port and a delivery port; the inlet port is hydraulically connected to an inlet manifold (IM), the storage unit is hydraulically connected to the inlet manifold (IM); 2. The anti-aquaplaning system of claim 1, wherein the delivery port is hydraulically connected to a delivery manifold (DM), and the dispensing unit is hydraulically connected to the delivery manifold (DM).

3. Selectively: a single fluid accumulator in fluid communication with the first injector and the second injector, the single fluid accumulator connected to the delivery manifold (DM) at a first junction, the first injector and the second injector connected to the delivery manifold (DM) at a second junction downstream of the first junction, a first flow control element hydraulically disposed between the second junction and the first injector, and a second flow control element hydraulically disposed between the second junction and the second injector. a single fluid accumulator in fluid communication with the first injector and the second injector, the single fluid accumulator being connected to the delivery manifold (DM) at a first junction, the first injector and the second injector being connected to the delivery manifold (DM) at a second junction downstream of the first junction, and a single flow control element being hydraulically disposed between the first junction and the second junction; a first fluid accumulator in fluid communication with the first injector and a second fluid accumulator in fluid communication with the second injector, a first flow control element is hydraulically disposed between the first fluid accumulator and the first injector, a second flow control element is hydraulically disposed between the second fluid accumulator and the second injector, and the first fluid accumulator and the second fluid accumulator are connected to the delivery manifold at a single junction; The anti-aquaplaning system of claim 2 .

4. the storage unit has at least one main reservoir configured to store a main operating fluid and an auxiliary reservoir configured to store a corresponding auxiliary operating fluid, each of the main reservoir and the at least one auxiliary reservoir including a hydraulic connection to the supply unit; 2. The anti-aquaplaning system of claim 1, further comprising a mixing unit configured to mix a predetermined amount of the primary operating fluid and a predetermined amount of the secondary operating fluid to define the operating fluid mixture of the anti-aquaplaning system.

5. 5. The anti-aquaplaning system of claim 4, wherein an inlet manifold (IM) is hydraulically connected to the main reservoir and the auxiliary reservoir, and the mixing unit comprises an electrically operated valve for the auxiliary reservoir configured to selectively enable liquid flow in the hydraulic connection between the auxiliary reservoir and the inlet manifold (IM) thereby enabling mixing between the main operating fluid and the corresponding auxiliary operating fluid to define the operating fluid mixture of the anti-aquaplaning system.

6. 3. The aquaplaning prevention system of claim 2, further comprising a cleaning manifold in fluid communication with the delivery manifold (DM) and another flow control element configured to selectively enable a flow of the working fluid mixture from the delivery manifold (DM) to the cleaning manifold, the cleaning manifold having a plurality of hydraulic cleaning lines connecting the cleaning manifold to corresponding cleaning devices configured to dispense the working fluid mixture towards corresponding sensors or equipment of a vehicle to clean the sensors or equipment, each hydraulic cleaning line including a valve configured to selectively enable a flow of the working fluid mixture to the corresponding cleaning device.

7. The anti-aquaplaning system of claim 2 , further comprising a pressure sensor configured to detect a pressure of the working fluid mixture in the delivery manifold (DM).

8. A method for dispensing a working liquid mixture into a delivery unit of an anti-aquaplaning system according to any one of claims 1 to 7, comprising the steps of: - activating said supply unit, thereby drawing said working liquid mixture from said storage unit and delivering said working liquid mixture to said at least one liquid accumulator until a filling pressure of said at least one liquid accumulator is reached; - stopping the activation of the supply unit when the filling pressure is reached; enabling a flow of the working fluid mixture in fluid communication between the at least one fluid accumulator and the first and second injectors in the event of an intervention of the anti-aquaplaning system including liquid injection using the first and second injectors; - disabling the flow of the working fluid mixture in fluid communication between the at least one fluid accumulator and the first injector and the second injector at the end of the intervention of the anti-aquaplaning system; a step of restarting the supply unit, whereby the hydraulic accumulator is filled with the working liquid mixture until a filling pressure is reached, the step of restarting the supply unit being carried out after the step of disabling the flow of the working liquid mixture. A method comprising:

9. 9. The method of claim 8, further comprising the step of enabling a flow of the working fluid mixture from a delivery manifold (DM) to a cleaning manifold and from the cleaning manifold to one or more hydraulic cleaning lines of the cleaning manifold, thereby delivering the working fluid mixture towards a corresponding sensor or equipment of a vehicle to clean the sensor or equipment, wherein the step of enabling a flow of the working fluid mixture from the delivery manifold (DM) to the cleaning manifold comprises the step of reducing the pressure of the working fluid mixture coming from the delivery manifold (DM).

10. 9. The method of claim 8, wherein the step of activating the supply unit, thereby drawing the working fluid mixture from the storage unit, comprises disabling the flow of the working fluid mixture in fluid communication between the at least one fluid accumulator and the first injector and the second injector.

11. 10. The method of claim 9, wherein the step of enabling a flow of the working fluid mixture from the delivery manifold (DM) to the cleaning manifold can be performed with transfer of the working fluid mixture in fluid communication between the at least one fluid accumulator and the first and second injectors disabled both in a state where the supply unit is active and in a state where the supply unit is inactive.

12. A motor vehicle comprising an anti-aquaplaning system according to any one of claims 1 to 7.

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