Description:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
(Section 10 and Rule 13)

TITLE OF THE INVENTION
A Vehicular Steering Wheel Assembly

APPLICANTS
Mahindra & Mahindra Limited, Mahindra Research Valley, Mahindra World City, Plot No:41/1, Anjur P.O., Chengalpattu, Tamilnadu – 6030

PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.

 

FIELD OF THE INVENTION
[001] The invention generally relates to a steering wheel assembly for a vehicle.

BACKGROUND OF THE INVENTION
[002] Infotainment systems are widely used in present day vehicles for infotainment and to enable users of the vehicles to interact with other subsystems of the vehicle. Infotainment systems generally are equipped with display screens or touchscreen display allowing a user to input multiple commands and display information on a single touchscreen display, which is unlike conventional buttons where a separate button is required to perform each specific action. Further, touchscreen displays are very responsive and work on the minutest touch without the user having to apply any sort of pressure while inputting commands. Touchscreen displays also improve aesthetics of a cabin of the vehicle. Further, touchscreen displays can also aid in overall cost reduction of the vehicle compared to a vehicle dashboard full of buttons and knobs, since a single touchscreen display is much more straightforward to design and maintain.
[003] However, options for placement of the touchscreen display in the vehicle are limited. Generally, the touchscreen display is disposed on a dashboard of the vehicle. In order to use the touchscreen or view information on it while the vehicle is in motion, a driver of the vehicle will have to take his or her eyes off a road and look downwards and sideways towards the touchscreen. Further, while looking away from the road, the user will have to free his or her hand from a steering wheel of the vehicle to input instructions in the touchscreen. This forces the driver to shift attention from the road to the touchscreen for a brief period of time and poses serious risk of accidents.
[004] Thus, it is preferable to minimise the angle to which the driver has to shift his or her gaze and minimize a distance to which the driver has to move his or her hand while interacting with the touchscreen. A solution is to mount the touchscreen on the steering wheel. However, when the touchscreen is mounted on the steering wheel it interferes with deployment of an airbag accommodated within a housing provided in the steering wheel. Further, owing to the sheer speed and momentum at which the airbag is deployed there is a risk that the touchscreen will be propelled towards the users of the vehicle causing impact and grave injury to them.
[005] Thus, there is a need in the art for a steering wheel assembly of a vehicle, which addresses at least the aforementioned problems.

SUMMARY OF THE INVENTION
[006] In one aspect the present invention provides a vehicular steering wheel assembly. The vehicular steering wheel assembly includes a steering wheel and a housing attached to the steering wheel. An operator of a vehicle manoeuvres the vehicle using the steering wheel assembly. The housing includes an opening facing the operator. The housing is further adapted to accommodate an airbag module. The airbag module has at least a folded airbag cushion and an inflator which is operable to inflate the airbag cushion towards the operator. A cover member is mounted to the housing to seal the opening of the housing. The cover member includes a tear line and a door hinge. The tear line and the door hinge define a door therebetween. The door is adapted to open about the door hinge and enables the inflating airbag cushion to be deployed outside the cover member and towards the operator. The vehicular steering wheel assembly further includes a display module attached to the door of the cover member by heat staking. The display module has a display screen to display information to the operator. The display module is adapted to move along with the door when it opens about the door hinge.
[007] In an embodiment, the display module includes a plurality of pins provided opposite to the display screen. The door of the cover member has a plurality of holes, and each hole corresponds to a pin of the display module. The plurality of holes is adapted to receive the corresponding pin to mount the display module to the door.
[008] In an embodiment, a tip of the plurality of pins received by the corresponding hole of the door is melted and fused to the door to securely attach the display module to the door.
[009] In an embodiment, the display screen of the display module is configured to receive touch inputs from the operator.
[010] In an embodiment, the tear line, the door hinge and the door are integrally part of the cover member.
[011] In an embodiment, the airbag cushion is deployed towards the operator by inflating it during a collision of the vehicle, when the collision exceeds a predefined impact threshold.
[012] In an embodiment, the door opens from the cover member along the tear line and pivotally rotates about the door hinge to reveal the opening of the housing during the deployment of the airbag cushion. The airbag cushion inflates through the opening so revealed to project outside the housing towards the operator to protect the operator from frontal impact.

BRIEF DESCRIPTION OF THE DRAWINGS
[013] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 shows a perspective view of a vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 2 shows an exploded view of the vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 3 shows a cross sectional view of the vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 4 shows a perspective view of a vehicular steering wheel assembly with an airbag cushion deployed in accordance with an embodiment of the invention.
Figure 5 shows a cover member of the vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 6 shows a sectional view of the cover member of the vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 7 shows an exploded view illustrating the cover member and a display module of the vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 8 shows the vehicular steering wheel assembly in accordance with an embodiment of the invention.
Figure 9 shows a perspective view of the vehicular steering wheel assembly in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION
[014] The present invention provides a vehicular steering wheel assembly capable of accommodating a display module on the steering wheel assembly without compromising on the deployment of the airbag cushion in case of a collision.
[015] Figure 1 shows a perspective view of a vehicular steering wheel assembly 100 in accordance with an embodiment of the invention. The steering wheel assembly 100 includes a steering wheel 110 by which an operator of a vehicle manoeuvres the vehicle, i.e., by turning the steering wheel 110, direction in which the vehicle turns can be changed and direction of motion of the vehicle can be varied. In the illustrated embodiment, the steering wheel 110 has a substantial circular ring shape. However, the steering wheel 110 may have any shape based on design requirements. A rear cover 160 is attached to the steering wheel 110. In the illustrated embodiment, the rear cover 160 is attached at a centre of the steering wheel 110. The rear cover 160 is adapted to house components of the steering wheel assembly 100.
[016] Figure 2 shows an exploded view of the vehicular steering wheel assembly 100 in accordance with an embodiment of the invention. The steering wheel assembly 100 includes a housing 120 attached to the steering wheel 110. The housing 120 has an opening 122 which faces the operator. A cover member 130 is mounted to the housing 120 and is adapted to seal the opening 122 of the housing 120. The housing 120 is covered by the rear cover 160 from a vehicle front to rear direction and covered by the cover member 130 from an operator to vehicle front direction. In an embodiment, the cover member 130 and the rear cover 160 enclose the housing 120 and components housed therein. The housing 120 accommodates an airbag module 200. Further, a display module 150 is mounted on the cover member 130. The display module 150 faces an operator of the vehicle and allows the operator to interact with the vehicle. The display module 150 includes a display screen 152 which displays information to the operator. In an embodiment, the display screen 152 has touch screen functionality allowing the operator to input commands to interact with the vehicle. The display and touch screen functionality is configurable and can vary as per requirement of the manufacturer/end-user. In an embodiment, the door 140 extends across the entire cover member 130 and a large display module 150 is attached to the door 140 as shown through the figures. In another embodiment, as shown in figure 9, the door 140 is provided at centre of cover member 130, and the display module 150 is attached to the door 140. In this regard, the size of the display module corresponds with the size of the door and can be varies as per requirement. As shown in figure 9, the display module 150 is smaller. However, as shown in figure 9, other display modules are mounted on the cover member 130 on either side of the display module 150, for touch and display capabilities.
[017] Figure 3 shows a cross sectional view of the vehicular steering wheel assembly 100 in accordance with an embodiment of the invention. The airbag module 200 includes at least an airbag cushion 210 and an inflator 220. In a non-deployed state, the airbag cushion 210 is folded and stored within the housing 120. The inflator 220 is operable to inflate the airbag cushion 210 towards the operator. The airbag module 200, the airbag cushion 210 and the inflator 220 can be of any design known in the art. Generally, upon detection of a collision which exceeds a predefined impact threshold, the inflator 220 inflates the airbag cushion 210 to deploy it towards the operator. Figure 4 shows a perspective view of the vehicular steering wheel assembly 100 with an airbag cushion 210 deployed in accordance with an embodiment of the invention. Sensors installed on the vehicle determine the impact induced by collision of the vehicle, and an actuator provided in the inflator 220 releases fluid into the airbag cushion 210. The fluid forces the airbag cushion 210 to rapidly expand and inflate before a head or body of the operator can collide with the steering wheel. Thus, in case of a collision when the airbag cushion expands, the head or body of the operator collides with the inflated airbag cushion 210 (shown in Figure 4) which then deflates to absorb the impact of collision to minimise injury to the operator. The present invention is capable of accommodating any method of inflating the airbag cushion 210 known in the art.
[018] Figure 5 shows a cover member 130 and Figure 6 shows a cross sectional view of the of the cover member 130 of the vehicular steering wheel assembly 100 in accordance with an embodiment of the invention. The cover member 130 includes a tear line 132 and a door hinge 134. A door 140 is defined in the cover member 130 between the tear line 132 and the door hinge 134. The door 140 is adapted to open about the door hinge 134 to enable the inflating airbag cushion 210 to be deployed through the door 140 to an outside of the cover member 130 towards the operator. In an embodiment, the tear line 132, the door hinge 134 and the door 140 are integrally formed with the cover member 130. This provides strength to the cover member 130 and does not allow the door 140 to open when pressure is applied externally on the door 140 by the operator. The door 140 separates from the cover member 130 along the tear line 132 and pivotally rotates about the door hinge 134 to deploy the airbag cushion 210 through the opening 122 of the housing 120. In an embodiment, the door 140 separates from the cover member 130 when there is a tearing along the tear line 132, which is caused by the sudden pressure exerted by the rapidly inflating airbag cushion 210. The tear line 132 being the weakest portion in the cover member 130 is specifically designed to separate from the cover member 130 under pressure exerted by the inflating airbag cushion 210. Once the door 140 is separated from the cover member 130 at the tear line 132, the door 140 is free to open about the door hinge 134. The airbag cushion 210 inflates through the opening 122 to project outside the housing 120 towards the operator to protect the operator from impact. As shown in the figures, the display module 150 is attached to the door 140 of the cover member 130, and the display module 150 is configured to move along with the door 140 when the door 140 opens about the door hinge 134.
[019] Figure 7 shows a perspective view of the cover member 130 and the display module 150 of the vehicular steering wheel assembly 100 in accordance with an embodiment of the invention. The display module 150 is attached to the door 140 by a process of heat staking. Attaching the display module 150 to the door 140 via heat staking ensures that the display module 150 is safely secured to the door 140 at all conditions, especially when the door 140 is suddenly popped open under pressure of the rapidly inflating airbag cushion 210. Instead of being separated from the door 140 to be propelled away under the immense force of the inflating air, the display module 150 is securely attached to the door 140 and moves with the door 140 while the airbag cushion 210 is being deployed. In an embodiment, the display module 150 has a plurality of pins 154 provided opposite the display screen 152, i.e., on the side of the display module 150 which is attached to the door 140. Correspondingly, the door 140 has a plurality of holes 144. Each hole 144 corresponds to a pin 154 of the display module 150, such that each pin 154 is adapted to receive the corresponding hole 144 to mount the display module 150 to the door 140.
[020] Figure 8 shows an exploded view of the vehicular steering wheel assembly 100 in accordance with an embodiment of the invention. The plurality of pins 154 which are inserted into their corresponding holes 144 enable the display module 150 to be attached to the door 140 by heat staking. A plurality of tips 156 of each of the plurality of pins 154 received by the corresponding plurality of holes 144 of the door 140 are melted and fused to the door 140 to securely attach the display module 150 to the door 140. After melting and fusing of the plurality of tips 156 of the plurality of pins 154, the plurality of tips 156 become larger than the hole 144 and prevent the plurality of pins 154 from being released from the corresponding holes. The fusing also produces a strong joint between the plurality of pins 154 and the door 140.
[021] Advantageously, the present invention provides a vehicular steering wheel assembly capable of accommodating a display module on a cover member of a steering wheel assembly while enabling an airbag cushion to be deployed without dislodging the display module from the cover member. Mounting of the display module to the cover member allows to minimise the angle to which the driver has to shift his or her gaze and minimise a distance to which the driver has to move his or her hand while interacting with a touchscreen of an infotainment system. The present invention enables such mounting of the display module on the cover member without compromising on the deployment of the airbag cushion from behind the cover member. Further, the display module is mounted in such a manner that the display module is not at the risk of being detached from the cover member and being propelled towards the users of the vehicle under the sheer speed and momentum at which the airbag is deployed
[022] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.
, Claims:WE CLAIM:
1. A vehicular steering wheel assembly (100) comprising:
a steering wheel (110) by which an operator of a vehicle manoeuvres the vehicle;
a housing (120) attached to the steering wheel (110), the housing (120) having an opening (122) facing the operator, and the housing (120) configured to accommodate an airbag module (200), the airbag module (200) having at least a folded airbag cushion (210) and an inflator (220) operable to inflate the airbag cushion (210) towards the operator;
a cover member (130) mounted to the housing (120) and configured to seal the opening (122) of the housing (120), the cover member (130) having a tear line (132) and a door hinge (134) defining a door (140) therebetween, the door (140) configured to open about the door hinge (134) enabling the inflating airbag cushion (210) to be deployed outside the cover member (130) towards the operator; and
a display module (150) attached to the door (140) of the cover member (130), the display module (150) having a display screen (152) configured to display information to the operator, and the display module (150) configured to move along with the door (140) when it opens about the door hinge (134), the display module (150) fused/bonded with the door (140) to prevent the display module (150) from separating off the door.

2. The vehicular steering wheel assembly (100) as claimed in claim 1, wherein the display module (150) comprising a plurality of pins (154) opposite the display screen (152), and the door (140) of the cover member (130) comprising a plurality of holes (144), each hole (144) corresponding to a pin (154) of the display module (150), wherein the plurality of holes (144) is configured to receive the corresponding pin (154) to mount the display module (150) to the door (140).

3. The vehicular steering wheel assembly (100) as claimed in claim 2, wherein the display module (150) being attached to the door (140) by heat staking, and a plurality of tips (156) of the plurality of pins (154) received by the corresponding hole (144) of the door (140) is melted and fused to the door (140) to securely attach the display module (150) to the door (140).

4. The vehicular steering wheel assembly (100) as claimed in claim 1, wherein the display screen (152) of the display module (150) is configured to receive touch inputs from the operator.

5. The vehicular steering wheel assembly (100) as claimed in claim 1, wherein the tear line (132), the door hinge (134) and the door (140) are an integral part of the cover member (130).

6. The vehicular steering wheel assembly (100) as claimed in claim 1, wherein the airbag cushion (210) is deployed towards the operator by inflation during a collision of the vehicle, when the collision exceeds a predefined impact threshold.

7. The vehicular steering wheel assembly (100) as claimed in claim 6, wherein the door (140) opens from the cover member (130) along the tear line (132) and pivotally rotates about the door hinge (134) to reveal the opening (122) of the housing (120) during the deployment of the airbag cushion (210), and the airbag cushion (210) inflating through the opening (122) so revealed to project outside the housing (120) towards the operator to protect the operator from frontal impact.

Dated this 17th day of January 2023
MAHINDRA & MAHINDRA LIMITED
By their Agent & Attorney

(Janaksinh Jhala)
of Khaitan & Co
Reg No IN/PA-2193