WO2018178791A1

WO2018178791A1 - A system to stabilize a vehicle by pivoting drive motor

Info

Publication number: WO2018178791A1
Application number: PCT/IB2018/051645
Authority: WO
Inventors: Srinivas Kudligi
Original assignee: Aditya Auto Products & Engg. (I) Pvt. Ltd
Priority date: 2017-03-31
Filing date: 2018-03-13
Publication date: 2018-10-04

Abstract

A system (100) to stabilize a vehicle is provided. The system (100) includes a drive motor (102) configured to drive the vehicle. The drive motor (102) is further configured to operably pivot about a lateral axis (118) of the vehicle.

Description

A SYSTEM TO STABILIZE A VEHICLE BY PIVOTING DRIVE MOTOR

BACKGROUND

Field [0001] The subject matter in general relates to automobiles. More particularly, but not exclusively, the subject matter relates to vehicle stabilization.

Discussion of related field

[0002] Vehicles are susceptible to rollovers either due to tripped rollovers or untripped rollovers. Tripped rollovers of the vehicle occur when manoeuvring over uneven terrain, hitting an obstacle with one of its wheels, crossing a ditch or slope and collision with another vehicle, among others. Untripped rollovers of the vehicle occurs during high speed cornering, where centrifugal force act through the vehicle's center of gravity causing the vehicle to roll.

[0003] Conventionally, rollover bars, Roll Over Protection Structures (ROPS) and roll cage are incorporated in the vehicle for protecting passengers in case of rollovers. However, such solutions do not stop the vehicle from rolling over.

[0004] Systems such as Electronic Stability Program (ESP), Roll Stability (RSP), Roll Stability Control (RSC), Roll Stability Support (RSS), Driver Support and Active Roll System, are known to prevent the vehicle roll. Most of these systems use sensors to identify the traction loss of a wheel, speed and other factors to either control the engine torque or braking one or more wheels to keep the vehicle stable. Further, all these systems require external systems with sophisticated algorithms to keep the vehicle stable, and are also expensive.

[0005] In view of the foregoing discussion, there is a need for an improved and economical technique for vehicle stability. SUMMARY

[0006] To fulfil the need for an improved and economical technique for vehicle stability, a system to stabilize the vehicle is provided in accordance with an embodiment. The system may include a drive motor configured to drive the vehicle. The drive motor may be further configured to operably pivot about a lateral axis of the vehicle. [0007] In an embodiment, the drive motor may be operably pivoted in clockwise and anti-clockwise direction about the lateral axis of the vehicle.

[0008] In an embodiment, an angle of the drive motor with respect to a longitudinal axis of the vehicle is based on an angle of rotation of a vehicle steering.

[0009] In an embodiment, an angle of the drive motor with respect to a longitudinal axis of the vehicle is based on speed of the vehicle.

[0010] In an embodiment, the system further comprises a constant velocity joint configured to transmit power from the drive motor to a differential of a rear axle of the vehicle.

[0011] In an embodiment, the drive motor comprises a pair of extended members extending from the drive motor, wherein the extended member is connected to the rear axle through a clevis joint, and the drive motor is pivoted about the clevis joint.

[0012] In an embodiment, the drive motor is pivoted using a rack and pinion mechanism.

[0013] In an embodiment a method for stabilizing a vehicle may include determining an angle of rotation of a vehicle steering and speed of the vehicle. The method may further include pivoting a drive motor about a lateral axis of the vehicle based on the determined angle of rotation of the vehicle steering and speed of the vehicle. The drive motor may be configured to drive the vehicle.

[0014] In an embodiment a method for stabilizing a vehicle may further include transmitting the power from the drive motor to a differential of a rear axle of the vehicle using a constant velocity joint.

BRIEF DESCRIPTION OF DRAWINGS

[0015] Embodiments are illustrated by way of example and not limitation in the Figures of the accompanying drawings, in which like references indicate similar elements and in which:

[0016] FIG. 1 is an exemplary illustration of a system 100 including a drive motor 102 to drive and stabilize a vehicle, in accordance with an embodiment;

[0017] FIG. 2 is an isometric view of the drive motor 102, in accordance with an embodiment; [0018] FIG. 3 is an exploded view of a constant velocity joint 106 transmitting power from the drive motor 102 to a differential 116 of the vehicle of FIG. 1, in accordance with an embodiment;

[0019] FIG. 4 is an isometric view of the clevis joint 110 of the system 100, in accordance with an embodiment; [0020] FIG. 5 illustrates a conventional vehicle cornering, in accordance with an embodiment;

[0021] FIG. 6A is an exemplary illustration of tilting drive motor 102 to create gyroscopic force to counter centrifugal force to stabilize the vehicle during cornering, in accordance with an embodiment; [0022] FIG. 6B is an exemplary illustration of a stable vehicle as a result of tilting drive motor 102 of FIG. 6A, in accordance with an embodiment;

[0023] FIG. 7 is an isometric view of a system 100 including a drive motor 102 to drive and stabilize a four-wheeled vehicle, in accordance with an embodiment; and

[0024] FIG. 8 is a flowchart of an exemplary method 800 for stabilizing a vehicle, in accordance with an embodiment.

DETAILED DESCRIPTION

[0025] The following detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show illustrations in accordance with example embodiments. These example embodiments, which may be herein also referred to as "examples" are described in enough detail to enable those skilled in the art to practice the present subject matter. The embodiments can be combined, other embodiments can be utilized, or structural, logical, and design changes can be made without departing from the scope of the claims. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope is defined by the appended claims and their equivalents.

[0026] In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one. In this document, the term "or" is used to refer to a nonexclusive "or," such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated.

[0027] FIG. 1 is an exemplary illustration of a system 100 including a drive motor 102 to drive and stabilize a vehicle, in accordance with an embodiment. The system 100 further includes a driveshaft 104, a constant velocity joint 106, a driven shaft 108, a clevis joint 110, extended members 112, a rear axle 114 and a differential 116. In the instant embodiment, the vehicle is a three-wheeled vehicle with one front wheel and two rear wheels. Further, Fig. 1 shows three mutually perpendicular axes with respect to the system 100, namely, lateral axis 118, longitudinal axis 120 and vertical axis 122.

[0028] The drive motor 102 may be configured to drive the vehicle by transmitting power from the driveshaft 104 to the differential 116 of a rear axle 114 through a constant velocity joint 106 and the driven shaft 108. The drive motor 102 may be configured to pivot about the lateral axis 118 of the vehicle to create a gyroscopic force to counter a centrifugal force created during turning of the vehicle, thereby forcing all the wheels to be in contact with the ground.

[0029] FIG. 2 is the drive motor 102 of the system 100 of the vehicle, in accordance with an embodiment. The drive motor 102 may include a rotor, a stator, a cover 206 and the driveshaft 104. The working principle of the drive motor 102 is similar to that of a conventional electric motor, where rotation of the rotor results in rotation of the driveshaft 104. The rotor, the stator and at least a portion of the driveshaftl04 may be housed in the cover 206. The extended members 112 may extend from one of the surfaces of the cover 206. In the instant embodiment, the extended members 112 may extend from the bottom surface of the cover 206. Each of the extended members 112 may define an aperture 208. In the instant embodiment, the rotor may rotate in clockwise direction when viewed from the top. In an embodiment, the rotor may act as a flywheel.

[0030] FIG. 3 is an exploded view of the constant velocity joint 106, in accordance with an embodiment. The constant velocity joint 106 may include a plurality of balls 302, an inner ball race 304 and an outer cage 306. The inner ball race 304 and the outer cage 306 may define a plurality of grooves to accommodate the plurality of balls 302. The constant velocity joint 106 when assembled, the plurality of balls 302 lies in between the inner race 304 and the outer cage 306. The inner ball race 304 may define a bore with serrations configured to receive the driveshaft 104 on one end. The driven shaft 108 may be received by the outer cage 306 on one end. The constant velocity joint 106 may be provided with boot for its protection. Various other implementations or variations of the constant velocity joint 106 known in the art may be utilized to achieve the same functionality.

[0031] FIG. 4 is an isometric view of the clevis joint 110 of the system 100, in accordance with an embodiment. The clevis joint 110 may include a pair of arms; each of the arms may include a first end 402 and a second end 404. The first end 402 may be fixed to the rear axle of the vehicle. The second end 404 may define an aperture 406. The extended member 112 are held together with the second end 404 of the clevis joint 110 using fasteners 408 that passes through the apertures 208 of the extended members 112 and the apertures 406 of the second end 404 of the clevis joint 110. In an example, stub pins may be used to fasten the extended member 112 with the clevis joint 110. With this arrangement of the extended members 112 and the clevis joint 110, the drive motor 102 may be operably pivoted about the fasteners 408 passing through the apertures 208 and 406. The drive motor 102 may be configured to pivot about the fasteners 408 in the longitudinal axis 120 of the vehicle.

[0032] Referring to FIG. 1, one end of the driven shaft 108 may be connected to the differential 116 and other end of the driven shaft 108 may be received by one end of the outer cage 306 of the constant velocity joint 106. One end of the inner ball race 304 of the constant velocity joint 106 may receive the driveshaft 104 of the drive motor 102. The apertures 208 of the extended member 112 may be aligned with the apertures 406 of the clevis joint 110 and fasteners 408 are used to hold the extended member 112 with the clevis joint 110 thereby holding the drive motor 102 with the clevis joint 110.

[0033] The drive motor 102 may be operably pivoted about the lateral axis 118 in a clockwise direction 124 and an anticlockwise direction 126 when viewed from right side of the vehicle as shown in FIG. 1. In an embodiment, the angle of the drive motor 102 with respect to a longitudinal axis 120 of the vehicle is based on an angle of rotation of a steering of the vehicle and speed of the vehicle. The angle of rotation of the steering may be with respect to a steering column. In an embodiment, pivoting of the drive motor 102 may be enabled by providing mechanical links between the steering and the extended member 112 of the drive motor 102. For example, a rack and pinion mechanism may be used to pivot the drive motor 102, wherein the pinion may be adapted to the drive motor 102 and the rack may be configured to slide based on the steering angle and the speed of the vehicle, thereby pivoting the drive motor 102. The gear ratio of the rack and pinion gears may be such that, pivoting of the drive motor 102 may generate a gyroscopic force that is equal in magnitude and opposite in direction to a centrifugal force acting on the vehicle during cornering. Alternatively, a motor and sensor arrangement may be used, wherein the motor is configured to pivot the drive motor 102 based on the angle of the steering and the speed of the vehicle determined by the sensor.

[0034] In an embodiment, one or more sensors may be used to sense angle of rotation of the steering of the vehicle and speed of the vehicle, a controller to determine the corresponding pivot angle for the drive motor 102 to force all the wheels of the vehicle to ground. Further a mechanical, electrical or electro-mechanical means to facilitate pivoting of the drive motor 102 to the determined pivot angle.

[0035] The vehicle steering may rotate in a first direction 128 and a second direction 130, such that, the first direction 128 and the second direction 130 are opposite to each other as shown in FIG. 1. Rotation of the steering in the first direction 128 may pivot the drive motor 102 in the clockwise direction 124 and rotation of the steering in the second direction 130 may pivot the drive motor 102 in the anticlockwise direction 126. In the instant embodiment, the first direction 128 is right direction and the second direction is left direction from a driver's perspective of the vehicle. The drive motor may remain in upright position as shown in FIG. 1 in case the vehicle is moving straight.

[0036] In conventional three-wheeled vehicles, turning the steering at high speed cornering will create a centrifugal force that lifts the inner wheel (the wheel closer to the turn) up and push the outer wheel (the wheel farther to the turn) down, thereby destabilizing the three-wheeler. [0037] FIG. 5 illustrates a conventional vehicle cornering, in accordance with an embodiment. In the instant embodiment, rotation of the steering in the second direction 130 (left direction) during high speed cornering will create a centrifugal force that lifts the vehicle's left rear wheel (due to upward force 502) up and pushes the vehicle's right rear wheel (due to downward force 504) down, thereby the vehicle becomes unstable resulting in roll of the vehicle. Alternatively, rotation of the steering in the first direction 128 (right direction) during high speed cornering will create a centrifugal force that lifts the vehicle's rear right wheel up and pushes the vehicle's rear left wheel down, thereby the vehicle becomes unstable resulting in roll of the vehicle.

[0038] FIG. 6A and 6B illustrates creating a gyroscopic force by tilting drive motor 102 to counter centrifugal force and stabilize a cornering vehicle, in accordance with an embodiment. In an example, the steering of the vehicle may be rotated in the second direction 130 (left direction) during high speed cornering as shown in FIG. 6 A. Further, the drive motor 102 is pivoted to counter the centrifugal force based on the angle of the steering and the speed of the vehicle. The drive motor 102 may be pivoted in anticlockwise direction 126 by a corresponding angle with respect to the longitudinal axis 120 of the vehicle. This results in generation of gyroscopic force in the opposite direction of the centrifugal force, thereby pushing the left rear wheel down (due to downward force 606) and lifts the right rear wheel (due to upward force 608) which nullifies the centrifugal force effect on the vehicle and keeping all the wheels in contact with ground. In an embodiment, the pivoting angle of the drive motor 102 may preferably range between 0 - 40 degrees.

[0039] The extended member 112 may pivot with respect to arms of the clevis joint about the fasteners 408 passing through apertures 208 and 406. The driveshaft 104 may continue to transmit constant power to the driven shaft 108 even when pivoted about inner ball race 304. This in turn will result in supply of constant power to the rear wheels of the vehicle through the differential 116. The pivoting of the drive motor 102 may be instantaneous to the rotation of the steering of the vehicle without any time lag resulting in continuous stability of the vehicle even while taking a turn.

[0040] In an embodiment, the drive motor is a pancake electric motor where the diameter of the rotor 202 is greater than the width of the rotor 202. Further, the length of the driveshaft 104 may also be reduced to enable the drive motor 102 to be positioned under the passenger's seat.

[0041] FIG. 7 illustrates a four-wheeled vehicle incorporated with the system 100 for stability, in accordance with an embodiment. The positioning and functioning of components of the system 100 of the four-wheeled vehicle is similar to that of the system 100 of the three- wheeled vehicle. During high speed cornering of the four-wheeled vehicle centrifugal force acting on the vehicle is nullified by creating gyroscopic force by pivoting the drive motor 102, thereby stabilizing the vehicle while cornering. [0042] FIG. 8 is a flowchart of an exemplary method 800 for stabilizing a vehicle, in accordance with an embodiment. At step 802, an angle of rotation of a vehicle steering and speed of the vehicle may be determined. At step 804, based on the determined angle of rotation of the vehicle steering and the speed of the vehicle, a drive motor 102 may be pivoted about a lateral axis of the vehicle. Power from the drive motor 102 may be transmitted to a differential 116 of a rear axle 114 of the vehicle using a constant velocity joint 106.

[0043] The present disclosure may provide a system including a drive motor configured to drive the vehicle and stabilize the vehicle during cornering. The present disclosure is advantageous in stabilizing the vehicle, without using additional expensive retrofits known in the art. The present disclosure provides an efficient and economical way to stabilize a vehicle as compared to existing solutions known in the art. The present disclosure may find its advantage in optimal utilization of the space under the passenger seat by using pancake electric motor. [0044] Although, embodiments have been described with reference to specific example embodiments, it will be evident that various modifications, arrangements of components and changes may be made to these embodiments without departing from the broader spirit and scope of technique for vehicle stability described herein. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.

[0045] Many alterations and modifications of the present invention will no doubt become apparent to a person of ordinary skill in the art after having read the foregoing description. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. It is to be understood that the description above contains many specifications; these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the personally preferred embodiments of this invention. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents rather than by the examples given.

Claims

CLAIMS I claim,

1. A system (100) to stabilize a vehicle, the system (100) comprises:

a drive motor (102) configured to:

drive the vehicle; and

operably pivot about a lateral axis (118) of the vehicle.

2. The system (100) of claim 1, wherein the drive motor (102) is operable to pivot in clockwise (124) and anti-clockwise (126) direction about the lateral axis (118) of the vehicle.

3. The system (100) of claim 1, wherein an angle of the drive motor (102) with respect to a longitudinal axis (120) of the vehicle is based on an angle of rotation of a vehicle steering.

4. The system (100) of claim 1, wherein an angle of the drive motor (102) with respect to a longitudinal axis (120) of the vehicle is based on speed of the vehicle.

5. The system (100) of claim 1, further comprises a constant velocity joint (106) configured to transmit power from the drive motor (102) to a differential (116) of a rear axle (114) of the vehicle.

6. The system (100) of claim 5, wherein the drive motor (102) comprises a pair of extended members (112) extending from the drive motor (102), wherein the extended members (112) are connected to the rear axle (114) through a clevis joint (110), and the drive motor (102) is pivoted about the clevis joint (110).

7. The system (100) of claim 1, wherein the drive motor (102) is pivoted using a rack and pinion mechanism.

8. The system (100) of claim 1, wherein the drive motor (102) is a pancake electric motor.

9. A method for stabilizing a vehicle, the method comprising: determining an angle of rotation of a vehicle steering and speed of the vehicle; and pivoting a drive motor (102) about a lateral axis (118) of the vehicle based on the determined angle of rotation of the vehicle steering and speed of the vehicle, wherein the drive motor (102) is configured to drive the vehicle.

10. The method according to claim 9, further comprising transmitting the power from the drive motor (102) to a differential (116) of a rear axle (114) of the vehicle using a constant velocity joint (106).