Splitter system for a vehicle with multiple wheels

Abstract

Splitter system (28) for a vehicle (10) with multiple wheels (42), wherein a vehicle body (14) is arranged along a longitudinal body axis (X) and includes a first vehicle body end, configured to meet the oncoming ambient air (27) when the vehicle (10) moves relative to a road surface (12), the splitter system (28) comprising: a splitter body (30) with a first splitter body side (30-1) and a second splitter body side (30-2), configured to be mounted at the first end of the vehicle body (14) and to generate an aerodynamic downforce (F D ) to generate at the first end of the vehicle body (14) when the vehicle (10) is in motion; a first winglet (32) operatively connected to the first splinter body side (30-1), and a second winglet (34) operatively connected to the second splinter body side (30-2), wherein the first and second winglets (32, 34) each comprise a winglet wall (32-1, 34-1), both arranged substantially vertically in relation to the road surface (12) and facing the oncoming ambient air (27) to close respective air gaps (27-2A, 27-3A) between the respective winglets (32, 34) and the vehicle body (14) when the vehicle (10) is in motion, wherein the first and second winglets (32, 34) are both configured to direct the oncoming ambient air (27) in relation to the splinter body (30) and around the left side wall (20) and the right side wall (22) of the vehicle body (14); a mechanism (36) configured to selectively adjust the first winglet (32) and the second winglet (34) in a direction transverse to the longitudinal axis (X) of the body, in order to adjust the strength of the aerodynamic downforce (F) generated by the splitter body (30) at the first end of the vehicle body (14). D ) to adjust; an electronic control unit (39) configured to control the mechanism (36); and several first sensors (44) configured to detect the rotational speed of each impeller (42) and to transmit the detected rotational speed of the respective impeller (42) to the control unit (39).

Description

TECHNICAL FIELD

[0001] The disclosure relates to an adjustable splitter for improving the aerodynamics of a motor vehicle. BACKGROUND

[0002] Aerodynamics is a key factor in the design of vehicles, including automobiles. Automotive aerodynamics is the study of the aerodynamics of road vehicles. The main objectives of the study are to reduce drag and wind noise to minimize noise emissions, as well as to prevent unwanted lift forces and other causes of aerodynamic instability at high speeds. Furthermore, the study of aerodynamics can also be used to generate downforce in high-performance vehicles to improve vehicle stability and cornering performance. The study is typically used to shape the vehicle body to achieve a desired compromise between the aforementioned properties for specific vehicle applications.

[0003] A splitter is an aerodynamic device sometimes used to increase the amount of downforce at the front of a vehicle. Typically, the airflow at the front of the vehicle is stagnated above the splitter by a front spoiler, creating a back pressure area. Below the splitter, the airflow is redirected away from the stagnation area and accelerated, reducing the pressure. The reduced pressure below the splitter, combined with the high pressure above the splitter, creates downforce (ground contact force) at the front of the vehicle. Generally speaking, the wider the splitter area, the more downforce is generated at the front of the vehicle.

[0004] US 8 210 600 B1 discloses an aerodynamic device for the front of a vehicle. US 2015 / 0 232 138 A1 teaches an adjustable flap for varying a vehicle's downforce. SUMMARY

[0005] A splitter system for a vehicle includes a splitter body having a first splitter body side and a second splitter body side. The vehicle includes a plurality of road wheels and a vehicle body arranged along a longitudinal axis, including a first body end configured to encounter the oncoming ambient airflow. The splitter body is configured to be mounted on the first end of the vehicle body to generate aerodynamic downforce thereat when the vehicle is in motion.The splitter system comprises a first winglet operatively connected to a first splitter body side, and a second winglet operatively connected to a second splitter body side, the first and second winglets each comprising a winglet wall, both arranged substantially vertically relative to the road surface and facing the oncoming ambient air to close respective air holes between the corresponding winglets and the vehicle body when the vehicle is in motion. The first and second winglets are configured to direct the movement of the oncoming ambient air relative to the splitter body and around the left sidewall and the right sidewall of the vehicle body. A mechanism is configured to selectively adjust both winglets in a direction transverse to the body's longitudinal axis to thereby regulate the aerodynamic downforce generated by the splitter body at the first body end of the vehicle.The splitter system further includes an electronic control unit configured to control the mechanism and a plurality of first sensors configured to detect a rotational speed of each impeller and to transmit the detected rotational speed of the respective impeller to the control unit.

[0006] The splitter system may also include a second sensor configured to detect a yaw rate of the vehicle body and transmit the detected yaw rate to the control unit.

[0007] The splitter system may also include a third sensor configured to detect a flow velocity of the incoming ambient air relative to the vehicle and to transmit the detected flow velocity of the ambient air to the control unit.

[0008] The vehicle may additionally include a steering wheel, and the splitter system may include a fourth sensor configured to detect the steering angle of the steering wheel.

[0009] The control unit may be configured to selectively adjust at least one of the first and second winglets via the mechanism in a direction transverse to the longitudinal body axis during cornering of the vehicle in response to the sensed yaw rate, the sensed steering angle of the steering wheel, and at least one of the sensed rotational speed of the impeller and the flow velocity of the ambient air, thereby regulating the aerodynamic downforce at the first body end of the vehicle and controlling the sensed yaw rate.

[0010] The control unit may additionally be programmed to selectively adjust at least the first or the second winglet via the mechanism, in a direction transverse to the longitudinal body axis, according to a look-up table that establishes a relationship between the extent of adjustment of the first winglet and the second winglet and the extent of aerodynamic downforce generated by the splitter at the first body end of the vehicle.

[0011] The mechanism may include at least a linear actuator, a rotary actuator and an electric motor.

[0012] In addition, a vehicle is disclosed that includes such a splitter system.

[0013] The above features and advantages, as well as other features and advantages of the present disclosure, will become apparent from the following detailed description of the embodiment(s) and the best mode(s) for carrying out the described disclosure with reference to the accompanying drawings and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic plan view of a vehicle with a vehicle body arranged in a body plane along a longitudinal axis and provided with a splitter system with movable winglets according to the disclosure. Fig. 2 is a schematic front view of the Fig. 1 of the disclosed vehicle. Fig. 3 is a schematic phantom representation of the Fig. 1-2, together with a detailed view of the disclosed splitter system. DETAILED DESCRIPTION

[0014] Referring to the drawings wherein like reference numerals refer to like components in several views, Fig. 1 is a schematic view of a motor vehicle 10 positioned relative to the road surface 12. The vehicle 10 includes a vehicle body 14 arranged in a body plane P that is substantially parallel to the road surface 12. The vehicle body 14 defines six body sides. The six body sides include a first body end, or front end, 16, an opposite second body end, or rear end, 18, a first lateral body side, or left side panel 20, and a second lateral body side, or right side panel 22, an upper body portion 24, which may include a vehicle roof, and an underbody portion (not shown).

[0015] The left sidewall 20 and the right sidewall 22 are generally parallel to each other and arranged relative to a virtual longitudinal axis X of the vehicle 10 and bridge the distance between the vehicle front 16 and the vehicle rear 18. The body plane P is defined to include the longitudinal axis X. A passenger compartment (not shown) of the vehicle 10 is generally bounded by the vehicle front and rear 16, 18 and the left and right sidewalls of the body 14. As one of ordinary skill in the art will understand, the vehicle front 16 is configured to encounter the oncoming ambient air 27 when the vehicle 10 is in motion relative to the road surface 12. When the vehicle 10 is in motion, the oncoming ambient air 27 moves substantially parallel to the body plane P and along the longitudinal axis X.As the vehicle 10 moves relative to the road surface 12, the ambient air 27 flows around the vehicle body 14 and is divided (split) into a first airflow portion 27-1, a second airflow portion 27-2, a third airflow portion 27-3, and a fourth airflow portion (not shown), which ultimately recombine in a wake or recirculation airflow region 27-6 directly behind the vehicle rear 18. In particular, as shown in FIG. Fig. 1, the first airflow portion 27-1 over the vehicle roof 24, a second airflow portion 27-2 past the left sidewall 20, a third airflow portion 27-3 past the right sidewall 22, and the fourth airflow portion, not specifically shown here, flows under the vehicle body 14 between the underbody portion and the road surface 12. As one of ordinary skill in the art will understand, the recirculating airflow region 27-6 generally arises at high vehicle speeds from the airflow flowing around the six sides of the vehicle body 14. As shown in the Fig. 1 and Fig. 2, the vehicle 10 also includes a splitter system 28. The splitter system 28 includes a splitter body 30 arranged along a splitter body axis Y and configured to direct the movement of the incoming ambient air 27 along the longitudinal body axis X of the vehicle body 14. As shown, the splitter body 30 is mounted on the vehicle front 16 to generate an aerodynamic downforce FD on the vehicle body 14 when the vehicle 10 is in motion. As can be understood, a pressure difference between the first airflow portion 27-1 and the fourth airflow portion 27-4 generated by the splitter body 30 determines the strength of the downforce FD acting on the vehicle front 16, with the first airflow portion having the greater pressure component. The splitter body 30 has a first splitter body side 30-1 and a second splitter body side 30-2.

[0016] The splitter system 28 also includes a first winglet 32 ​​operatively connected to the first splitter body side 30-1 and a second winglet 34 operatively connected to the second splitter body side 30-2. The two winglets 32, 34 are arranged substantially transversely relative to the splitter body axis Y and each include a winglet wall 32-1 and a winglet wall 34-1, both arranged substantially vertically relative to the road surface 12 and facing the oncoming ambient air 27. As a result, the winglet walls 32-1, 34-1 facilitate the closure of respective air holes 27-2A, 27-3A between the corresponding winglets 32, 34 and the vehicle body 14 when the vehicle 10 is in motion. Accordingly, the first and second winglets 32, 34 are configured to direct the movement of the second and third airflow portions 27-2, 27-3 relative to the splitter body 30 and around the left sidewall 20 and the right sidewall 22 of the vehicle body 14.

[0017] As in Fig. 3, the splitter system 28 also includes a mechanism 36 configured to selectively adjust the first winglet 32 ​​and the second winglet 34 along the Y-axis of the splitter body, i.e., in a direction substantially transverse to the body's longitudinal axis X. As a result, the mechanism 36 can adjust the first and second winglets 32, 34 toward and away from the first and second lateral body sides 20, 22. Such adjustment of the first winglet 32 ​​and the second winglet 34 changes the position of the winglets relative to the first and second lateral body sides 20, 22 to increase or decrease the attack areas of the winglet walls 32-1, 34-1. The adjustment of the attack surfaces of the winglet walls 32-1, 34-1 in turn changes the size of the respective air holes 27-2A, 27-3A and thus regulates the strength of the aerodynamic downforce FD generated by the splitter body 30 on the body front 16.

[0018] To facilitate adjustment along the Y-axis of the splitter body, the first winglet 32 ​​and the second winglet 34 may be movably mounted on the splitter body 30 adjacent the first end 30-1 and the second end 30-2, respectively. Means 32-2, 34-2 may be provided on the first and second winglets 32, 34, respectively, for engaging and sliding relative to the additional channels 20A and 22A on the left and right sidewalls 20, 22. The ends 30-1, 30-2 of the splitter body 30 may also be configured to slide in respective channels 32-3, 34-3 on the first and second winglets 32, 34. Conversely, the ends 30-1, 30-2 of the splitter body 30 may include channels that may receive devices (not shown) on the first and second winglets 32, 34 for sliding movement of the winglets relative to the splitter body.

[0019] The mechanism 36 may include a set of individual devices 38 for adjusting each winglet 32, 34 toward or away from the respective first and second lateral body sides 20, 22. Such a set of individual devices 38 may consist of a specific device 38 for adjusting the first winglet 32 ​​and another specific device 38 for adjusting the second winglet 34. Each device 38 may be arranged between the vehicle body 14 and the corresponding first and second winglets 32, 34 to generate movement of the first and second winglets; it may be a linear actuator, a rotary actuator, and / or an electric motor (not shown in detail, but understandable to one of ordinary skill in the art). As shown in Fig. 3, each device 38 may be configured to exert a force F1 to adjust each of the first and second winglets 32, 34 in one direction, and an opposite force F2 to adjust the corresponding winglets in the opposite direction.

[0020] As in the Fig. 1-3, the vehicle also includes an electronic control unit 39 configured, ie constructed and programmed, for adjusting the mechanism 36. The control unit 39 may be designed as a central processing unit (CPU) configured to control the operation of the internal combustion engine 40 (shown in Fig. 1), a hybrid-electric powertrain (not shown), or other alternative powerplant types and vehicle systems, or as a dedicated control unit. To suitably control the mechanism 36, the control unit 39 includes a memory, at least a portion of which is tangible and non-volatile. The memory may be any writable medium involved in providing computer-readable data or process instructions. Such a medium may be in any format, including, but not limited to, non-volatile media and volatile media. Non-volatile media for the memory 39 may include, for example, image or magnetic disks and other persistent storage. Volatile media may include, for example, dynamic random access memory (DRAM), which may constitute main memory.Such instructions may be transmitted by one or more transmission media, including coaxial cable, copper wire, and fiber optics, including the conductors comprising a system bus coupled to the processor. The memory of the control unit 39 may also consist of a floppy disk, a flexible diskette, a hard disk, magnetic tape, any other magnetic medium, a CD-ROM, a DVD, or any other optical medium, etc. The control unit 39 may be configured or equipped with, or may be configured to include, other required computer hardware, such as a high-speed clock, necessary analog-to-digital (A / D) and / or digital-to-analog (D / A) circuitry, any required input / output (I / O) circuitry and devices, and appropriate signal conditioning and / or buffer circuitry.Any algorithms required or accessible to the control unit 39 can be stored in memory and executed automatically to provide the requested functionality.

[0021] As in Fig. 1, the vehicle 10 also includes road wheels 42. A plurality of first sensors 44 may be disposed on the vehicle body 14 to detect the rotational speed of each road wheel 42. Each first sensor 44 may also be configured to transmit the detected rotational speed of the respective road wheel 42 to the control unit 39, while the control unit may be configured to convert the data received from the respective first sensors into the traveling speed of the vehicle 10. The vehicle 10 may also include a second sensor 46 configured to detect a yaw force or rate of the vehicle body 14 relative to the road surface 12 and to transmit the detected yaw rate to the control unit 39.The vehicle may additionally include a third sensor 48 configured to detect the incoming air flow velocity of the ambient air 27 relative to the vehicle 10 and to transmit the detected incoming air flow velocity to the control unit 39. The third sensor 48 may be a pitot tube configured to detect the pressure of the incoming ambient air 27 at a specific location on the vehicle body 14, and the control unit 39 may convert the measured pressure into the air flow velocity.

[0022] The control unit 39 is additionally configured, via the mechanism 36, to selectively adjust the first and second winglets 32, 34 along the Y-axis of the splitter body, toward or away from the respective first and second lateral body sides 20, 22, during cornering of the vehicle 10 in response to the yaw rate detected by the second sensor 46. For example, when the vehicle 10 is cornering at high speed (high G-value), the first and second winglets 32, 34 can be stretched away from the respective side walls 20, 22 to increase the downforce FD acting on the vehicle front 16 and improve the vehicle's ability to maintain the selected lane in the curve.Accordingly, the position of the first and second winglets 32, 34 can be adjusted via the control unit 39 along the body longitudinal axis X and in relation to the respective side wall 20, 22, proportional to the yaw rate generated when the vehicle 10 corners, by adjusting the respective winglets.

[0023] Furthermore, the control unit 39 can be configured to selectively adjust the first and second winglets 32, 34 along the Y-axis of the splitter body towards or away from the respective first and second lateral body sides 20, 22 via the mechanism 36, in response to the rotational speeds of the road wheels 42 detected by the first sensor 44 and / or the flow velocity of the ambient air 27 detected by the third sensor 48. For example, when the vehicle 10 is traveling at an increased speed, the first and second winglets 32, 34 can be stretched away from the respective side walls 20, 22 in order to increase the downforce FD acting on the vehicle front 16 and to improve the stability and steering response of the vehicle under these conditions.On the other hand, the first and second winglets 32, 34 can be retracted towards the respective side walls 20, 22 in order to reduce the downforce FD and as a result increase the aerodynamic drag of the vehicle 10.

[0024] The control unit 39 may also be programmed to determine a slip of the vehicle 10 relative to the road surface 12. The slip of the vehicle 10 may include a measure of how much each of the road wheels 42 has slipped in a direction generally perpendicular to the vehicle X-axis, thereby determining that the vehicle has deviated from an intended direction or trajectory along the road surface 12. The intended direction of the vehicle 10 may be defined by the steering wheel angle provided by the fourth steering wheel 52 operatively connected (shown in Fig.1) Sensor 50 and transmitted to the control unit 39. Furthermore, the control unit 39 can be programmed to compare the detected steering wheel angle with the yaw rate to determine how much the vehicle has deviated from its intended direction or trajectory.

[0025] The control unit 39 can also be programmed to control the slip of the vehicle 10 relative to the road surface 12 by controlling the position of the first and second winglets 32, 34 relative to the corresponding sidewalls 20, 22 via the mechanism 36 in response to how far the vehicle has deviated from its intended path. The practiced change in the position of the first and second winglets 32, 34 then causes the vehicle 10 to return from the current direction of travel to the intended direction of travel, which is determined by the vehicle operator at the steering wheel 52. In addition, two third sensors 48 can be mounted on the splitter body 30, one such third sensor at the first end 30-1 and another third sensor at the other end 30-2 (not shown).The control unit 39 may then be configured to change the position of the first and second winglets 32, 34 relative to the respective body sides 20, 22 in response to a detected difference between the airflow velocities measured at each third sensor 48 as the vehicle 10 enters and negotiates a curve to change the downforce FD on the vehicle body 14.

[0026] The control unit 39 can additionally be programmed with a lookup table 54 that establishes a relationship between the vehicle parameters described above—the slip, the yaw rate, the vehicle's ground speed, and / or the airflow velocity—and the corresponding position of the winglets 32, 34 in order to appropriately influence the control of the mechanism 36. In particular, the lookup table 54 can establish a relationship between the extent of adjustment of the first winglet 32 ​​and the second winglet 34 and the extent of aerodynamic downforce FD generated by the splitter system 28 at the vehicle front 16. The lookup table 54 can be created empirically during the validation and testing phase of the vehicle 10.When the position of the first and second winglets 32, 34 is adjusted relative to the corresponding side walls 20, 22 during cornering or at increased driving speeds, the splitter system 28 can regulate the downforce FD at the front end of the vehicle body 14 in order to influence the dynamic handling of the vehicle 10.

[0027] Accordingly, controlling the position of the first and second winglets 32, 34 can be used to maintain contact of the vehicle 10 with the road surface 12 at high speeds by counteracting the aerodynamic lift of the vehicle body 14 in response to the ambient air velocity 27 detected by the third sensor 48. In addition, controlling the position of the first and second winglets 32, 34 can be used to assist the handling of the vehicle 10 by counteracting and controlling the yaw moment acting on the vehicle body 14, as detected by the second sensor 46, and thus keeping the vehicle in its intended trajectory.

Claims

[1] A splitter system (28) for a vehicle (10) having a plurality of road wheels (42), in which a vehicle body (14) is arranged along a body longitudinal axis (X) and includes a first vehicle body end configured to encounter the incoming ambient air (27) when the vehicle (10) moves relative to a road surface (12), the splitter system (28) comprising: a splitter body (30) having a first splitter body side (30-1) and a second splitter body side (30-2), configured to be mounted on the first end of the vehicle body (14) and to provide an aerodynamic downforce (F D ) at the first end of the vehicle body (14) when the vehicle (10) is in motion; a first winglet (32) operatively connected to the first splitter body side (30-1), and a second winglet (34) operatively connected to the second splitter body side (30-2), wherein the first and second winglets (32, 34) each comprise a winglet wall (32-1, 34-1), both arranged substantially vertically relative to the road surface (12) and facing the oncoming ambient air (27) to close respective air holes (27-2A, 27-3A) between the corresponding winglets (32, 34) and the vehicle body (14) when the vehicle (10) is in motion, wherein the first and second winglets (32, 34) are both configured to direct the oncoming ambient air (27) relative to the splitter body (30) and around the left side wall (20) and the right side wall (22) of the vehicle body (14) lead; a mechanism (36) configured to selectively adjust the first winglet (32) and the second winglet (34) in a direction transverse to the body longitudinal axis (X) to thereby adjust the strength of the aerodynamic downforce (F D ) to set; an electronic control unit (39) configured to control the mechanism (36); and a plurality of first sensors (44) configured to detect a rotational speed of each impeller (42) and to transmit the detected rotational speed of the respective impeller (42) to the control unit (39). [2] The splitter system (28) of claim 1, further comprising a second sensor (46) configured to detect a yaw rate of the vehicle body (14) and to transmit the detected yaw rate to the control unit (39). [3] Splitter system (28) according to claim 2, further comprising a third sensor (48) configured to detect a flow velocity of the incoming ambient air (27) relative to the vehicle (10), and to transmit the detected flow velocity of the ambient air (27) to the control unit (39). [4] The splitter system (28) of claim 3, wherein the vehicle (10) includes a steering wheel (52), and the splitter system (28) includes a fourth sensor (50) configured to detect the steering angle of the steering wheel (52). [5] Splitter system (28) according to claim 4, wherein the control unit (39) is configured to selectively adjust at least one of the first and second winglets (32, 34) via the mechanism (36) in a direction transverse to the body longitudinal axis (X) during cornering of the vehicle (10), in response to the sensed yaw rate, the sensed steering angle of the steering wheel (52), and at least one of the sensed rotational speeds of the impeller (42) and the incident air flow velocity (27), to thereby adjust the aerodynamic downforce (F D ) at the first body end of the vehicle (10) and to bring the detected yaw rate under control. [6] Splitter system (28) according to claim 5, wherein the control unit (39) is programmed to selectively adjust at least one of the first and second winglets (32, 34) via the mechanism (36) in a direction transverse to the body longitudinal axis (X), according to a look-up table (54) defining a relationship between the extent of adjustment of the first winglet (32) and the second winglet (34) and the extent of aerodynamic downforce (F D ) generated by the splitter at the first end of the vehicle body (10). [7] The splitter system (28) of claim 1, wherein the mechanism (36) includes at least one of a linear actuator, a rotary actuator, and an electric motor.

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