Description:TECHNICAL FIELD
[001] The embodiments herein generally relate to steering systems in vehicles and more particularly, to a steering column assembly for a vehicle, which is collapsible and de-couplable to restrict a movement of the steering column assembly thereby reducing intrusion of steering wheel in a direction towards a vehicle’s operator (driver) in an event of frontal collision of the vehicle.
BACKGROUND
[002] Generally, a steering system is used to control a directional change in movement of a vehicle and maintains the vehicle in a position as per the decision of a vehicle’s operator (driver) driving the vehicle. The steering system is used to convert rotary movement of a steering wheel into angular turn of wheels of the vehicle. Typically, the steering system includes a steering column assembly which is used for connecting the steering wheel to a steering gear mechanism. The steering system is very critical from crash point of view since serious injury to driver may be caused due to impact by the steering column and steering wheel on the driver’s body in case of a frontal collision of the vehicle. Thus, collapsible steering columns are installed in the vehicles to collapse in a controlled manner to reduce serious injury to the driver during the frontal collision of the vehicle. Further, the steering column assembly should be able to collapse away from the driver of the vehicle. In vehicles such as sport utility vehicles (SUV), stroke length of collapse is limited, and sometimes complete stroke length is not utilized thereby causing steering wheel intrusion and also some vehicles have steering rack gear placed in front of an engine resulting in early start of steering wheel intrusion.
[003] Therefore, there exists a need for a steering column assembly for a vehicle, which obviates the aforementioned drawbacks.
OBJECTS
[004] The principal object of embodiments herein is to provide a steering column assembly for a vehicle, which is collapsible and de-couplable to restrict a movement of the steering column assembly thereby reducing intrusion of a steering wheel in a direction towards a vehicle’s operator (driver) in an event of frontal collision of the vehicle.
[005] Another object of embodiments herein is to provide a method for restricting the movement of the steering column assembly during the frontal collision of the vehicle.
[006] Another object of embodiments herein is to provide the steering column assembly for a sport utility vehicle (SUV), which is configured to absorb impact energy as well as reduce intrusion of the steering wheel within the limited collapse stroke of the steering column assembly.
[007] Another object of embodiments herein is to de-couple a first steering column from a second steering column to restrict a movement of a steering wheel in a direction towards the vehicle’s operator thereby reducing injury to the vehicle’s operator in the event of frontal collision of the vehicle.
[008] Another object of embodiments herein is to provide the steering column assembly, which is easy to manufacture and is inexpensive.
[009] These and other objects of embodiments herein will be better appreciated and understood when considered in conjunction with following description and accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[0010] The embodiments are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0011] Fig. 1 depicts an exploded view of a steering column assembly for a vehicle, according to embodiments as disclosed herein;
[0012] Fig. 2 depicts a perspective view of the steering column assembly, according to embodiments as disclosed herein;
[0013] Fig. 3A depicts a side view of the steering column assembly, according to embodiments as disclosed herein;
[0014] Fig. 3B depicts a cross-sectional view of the steering column assembly taken along a line A-A of fig. 3A, according to embodiments as disclosed herein;
[0015] Fig. 4 depicts top view and side view of a torque transmitting member of the steering column assembly, according to embodiments as disclosed herein;
[0016] Fig. 5A depicts a side view of the steering column assembly after frontal collision of the vehicle, according to embodiments as disclosed herein;
[0017] Fig. 5A depicts a cross-sectional view of the steering column assembly taken along line C-C of fig. 5A after a frontal collision of the vehicle, according to embodiments as disclosed herein; and
[0018] Fig. 6 depicts a flowchart indicating steps of a method for restricting a movement of the steering column assembly during a frontal collision of the vehicle, according to embodiments as disclosed herein.
DETAILED DESCRIPTION
[0019] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0020] The embodiments herein achieve a steering column assembly for a vehicle, which is collapsible and de-couplable to restrict a movement of the steering column assembly thereby reducing intrusion of a steering wheel in a direction towards a vehicle’s operator (driver) in an event of a frontal collision of the vehicle. Referring now to figs. 1 through 6, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0021] Fig. 1 depicts an exploded view of a steering column assembly (100) for a vehicle, according to embodiments as disclosed herein. In an embodiment, the steering column assembly (100) includes a first steering column (102), a universal joint (103), a second steering column (104), a steering shaft (106), a torque transmitting member (108), a steering column de-coupling member (110), at least one steering column locking member (112), a plurality of lock bolts (114F, 114S) and a spring (116). For the purpose of this description and ease of understanding, the steering column assembly (100) is explained herein with below reference to restrict a movement of the steering column assembly (100) thereby reducing intrusion of a steering wheel (not shown) in a direction towards a vehicle’s operator in an event of a frontal collision of a passenger vehicle. However, it is also within the scope of the invention to use/practice the components of the steering column assembly (100) in any other agricultural machines or any other off-road vehicles or any other vehicles, where restricting the movement of steering column assembly for reducing intrusion of steering wheel is required during frontal collision of the vehicle, without otherwise deterring the intended function of the steering column assembly (100) as can be deduced from the description and corresponding drawings.
[0022] The first steering column (102) is rotatably coupled to the steering wheel (not shown) through the universal joint (103). A front end (102F) of the first steering column (102) is connected to the universal joint (103), and a rear end (102R) of the first steering column (102) is connected to a first portion ((108F), as shown in fig. 3B)) of the torque transmitting member (108).
[0023] The second steering column (104) is rotatably coupled to the first steering column (102) through the torque transmitting member (108). Further, the second steering column (104) is rotatably coupled to a steering gear assembly (not shown) through the steering shaft (106). For the purpose of this description and ease of understanding, the steering gear assembly (not shown) is considered to be a steering rack and pinion gear assembly. The second steering column (104) is positioned co-axially below the first steering column (102).
[0024] The steering shaft (106) is adapted to transmit the torque received from the second steering column (104) to the steering gear assembly (not shown). The steering shaft (106) includes a first portion (106F) and a second portion (106S), as shown in fig. 3B. The first portion (106F) of the steering shaft (106) is spline fitted into the second steering column (104). The second portion (106S) of the steering shaft (106) is located external with respect to the second steering column (104).
[0025] The torque transmitting member (108) is adapted to transmit torque from the first steering column (102) to the second steering column (104) on rotation of the steering wheel (not shown). The torque transmitting member (108) is adapted to rotatably connect the first steering column (102) to the second steering column (104). A first portion (108F) and a second portion (108S) (as shown in fig. 3B) of the torque transmitting member (108) are located inside a rear end (102R) (as shown in fig. 3B) of the first steering column (102) and a front end (104F) (as shown in fig. 3B) of the second steering column (104) respectively. The torque transmitting member (108) includes an elongated groove (108G) (as shown in fig. 4) adapted to receive a bottom end of each lock bolt (114F, 114S) thereby allowing the steering column locking member (112) to be externally mounted onto the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104) respectively. There is a clearance between the elongated groove (108G) of the torque transmitting member (108) and the plurality of lock bolts (114F, 114S). Further, the torque transmitting member (108) includes a first external spline section (not shown) defined on the first portion (108F). The first external spline section (not shown) of the torque transmitting member (108) is engaged with corresponding first internal spline section (not shown) defined in the rear end (102R) of the first steering column (102). It is also within the scope of the invention to use any other engaging mechanism in place of external and internal splines for connecting the torque transmitting member (108) with the first steering column (102). Furthermore, the torque transmitting member (108) includes a second external spline section (not shown) defined on the second portion (108S). The second external spline section of the torque transmitting member (108) is engaged with corresponding second internal spline section (not shown) defined in the front end (104F) of the second steering column (104). It is also within the scope of the invention to use any other engaging mechanism in place of external and internal splines for connecting the torque transmitting member (108) with the second steering column (104).
[0026] The steering column de-coupling member (110) is adapted to deform (shear) which in turn causes deformation (shearing) of the steering column locking member (112) thereby de-coupling the first steering column (102) from the second steering column (104) for reducing intrusion of steering wheel (not shown) in a direction towards the vehicle’s operator (driver) during frontal collision of the vehicle. The steering column de-coupling member (110) is adapted to be located inside the second steering column (104) in vicinity of the second portion (108S) of the torque transmitting member (108). The steering column de-coupling member (110) is positioned immediately between the second portion (108S) of the torque transmitting member (108) and the first portion (106F) of said steering shaft (106). The steering column de-coupling member (110) includes a first section (110F), a second section (110S) and a circumferential groove (110G) (as shown in fig. 1). The first section (110F) of the steering column de-coupling member (110) is engaged with the second portion (108S) (as shown in fig. 3B) of the torque transmitting member (108). The second section (110S) of the steering column de-coupling member (110) is engaged with the first portion (106F) of the steering shaft (106). The circumferential groove (110G) is defined between the first section (110F) and the second section (110S) of the steering column de-coupling member (110).
[0027] The steering column locking member (112) is adapted to lock the first steering column (102) with the second steering column (104) via the plurality of lock bolts (114F, 114S) thereby transmitting the torque received from the first steering column (102) to the second steering column (104). A first portion (112F) and a second portion (112S) (as shown in fig. 2) of the steering column locking member (112) are adapted to be externally mounted onto the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104) respectively via the plurality of lock bolts (114F, 114S) thereby connecting the first steering column (102) to the second steering column (104).
[0028] The plurality of lock bolts (114F, 114S) are adapted to lock the steering column locking member (112) onto the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104). The plurality of lock bolts (114F, 114S) includes a first lock bolt (114F) and a second lock bolt (114S). The first lock bolt (114F) is adapted to be received by a first lock bolt receiving portion (opening) (102S, 112A, as shown in fig. 1) defined in each of the steering column locking member (112) and the rear end (102R) of the first steering column (102) to lock the first portion (112F) of the steering column locking member (112) onto the rear end (102R) of the first steering column (102). The second lock bolt (114S) is adapted to be received by a second lock bolt receiving portion (opening) (104S, 112B) (as shown in fig. 1) defined in each of the steering column locking member (112) and the front end (104F) of the second steering column (104) to lock the second portion (112S) of the steering column locking member (112) onto the front end (104F) of the second steering column (104).
[0029] One end of the spring (116) is engaged with the universal joint (103) and another end of the spring (116) is engaged with the torque transmitting member (108). The spring (116) is adapted to keep the torque transmitting member (108) in spline engagement with the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104).
[0030] The steering shaft (106) is adapted to push the steering column de-coupling member (110) against the torque transmitting member (108) when the steering shaft (106) receives impact energy in an event of frontal collision of the vehicle. Further, the steering column de-coupling member (110) is adapted to push an entirety of the torque transmitting member (108) into the first steering column (102) thereby initiating de-coupling of the first steering column (102) from the second steering column (104) when the steering column de-coupling member (110) is pushed against the torque transmitting member (108) by the steering shaft (106).
[0031] The steering column de-coupling member (110) is configured to deform (shear) into two pieces due to shearing of the circumferential groove (110G) (as shown in fig. 1) thereby causing deformation (shearing) of the steering column locking member (112) to de-couple the first steering column (102) from the second steering column (104) when the first section (110F) and the second section (110S) of the steering column de-coupling member (110) come in engagement with the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104) respectively (as shown in fig. 5B) during frontal collision of the vehicle. The rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104) are tapered to facilitate deformation (shearing) of the steering column de-coupling member (110) during frontal collision of the vehicle. For example, the inner portion of each of the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104) are tapered. Further, in another example, a circumferential edge of each of the rear end (102R) of the first steering column (102) and the front end (104F) of the second steering column (104) are tapered. The steering column de-coupling member (110) is made of lighter material when compared to a material of the torque transmitting member (108).
[0032] The steering column locking member (112) is configured to deform in which the first portion (112F) is separated (sheared) from the second portion (112S) of the steering column locking member (112) due to deformation of the steering column de-coupling member (110) thereby de-coupling the first steering column (102) from the second steering column (104).
[0033] Fig. 6 depicts a flowchart indicating steps of a method (200) for restricting a movement of the steering column assembly (100) during a frontal collision of the vehicle, according to embodiments as disclosed herein. At step (202), the method (200) includes pushing, by a steering shaft (106), a steering column de-coupling member (110) against a torque transmitting member (108) when the steering shaft (106) receives impact energy during the frontal collision of the vehicle. At step (204), the method (200) includes pushing, by the steering column de-coupling member (110), an entirety of the torque transmitting member (108) into a first steering column (102) thereby initiating de-coupling of the first steering column (102) from a second steering column (104) when the steering column de-coupling member (110) is pushed against the torque transmitting member (108) by the steering shaft (106).
[0034] At step (206), the method (200) includes deforming (shearing), by the steering column de-coupling member (110) causes deformation (shearing) of the steering column locking member (112) thereby de-coupling the first steering column (102) from the second steering column (104) when a first section (110F) and a second section (110S) of the steering column de-coupling member (110) come in engagement with a rear end (102R) of the first steering column (102) and a front end (104F) of the second steering column (104) respectively during the frontal collision of the vehicle.
[0035] The technical advantages of the steering column assembly (100) are as follows. The steering column assembly (100) is configured to absorb impact energy as well as reduce intrusion of steering wheel within the limited collapse stroke of the steering column assembly. The steering column assembly is easy to manufacture and is inexpensive.
[0036] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the spirit and scope of the embodiments as described herein.
, Claims:We claim,
1. A steering column assembly (100) for a vehicle, said steering column assembly (100) comprising:
a first steering column (102) coupled to a steering wheel through a universal joint (103);
a second steering column (104) coupled to a steering gear assembly through a steering shaft (106);
a torque transmitting member (108) adapted to rotatably connect said first steering column (102) to said second steering column (104), wherein a first portion (108F) and a second portion (108S) of said torque transmitting member (108) are located inside a rear end (102R) of said first steering column (102) and a front end (104F) of said second steering column (104) respectively; and
a steering column de-coupling member (110) adapted to be located inside said second steering column (104) in vicinity of said second portion (108S) of said torque transmitting member (108).
2. The steering column assembly (100) as claimed in claim 1, wherein said steering column assembly (100) includes at least one steering column locking member (112) adapted to lock said first steering column (102) with said second steering column (104) via a plurality of lock bolts (114F, 114S).
3. The steering column assembly (100) as claimed in claim 2, wherein said steering shaft (106) includes a first portion (106F) and a second portion (106S), wherein said first portion (106F) is spline fitted into said second steering column (104);
said second portion (106S) of said steering shaft (106) is located external with respect to said second steering column (104);
said steering column de-coupling member (110) is positioned immediately between said second portion (108S) of said torque transmitting member (108) and said first portion (106F) of said steering shaft (106); and
said steering column de-coupling member (110) includes a first section (110F), a second section (110S) and a circumferential groove (110G), wherein said circumferential groove (110G) is defined between said first section (110F) and said second section (110S).
4. The steering column assembly (100) as claimed in claim 3, said steering shaft (106) is adapted to push said steering column de-coupling member (110) against said torque transmitting member (108) when said steering shaft (106) receives impact energy in an event of frontal collision of said vehicle; and
said steering column de-coupling member (110) is adapted to push an entirety of said torque transmitting member (108) into said first steering column (102) thereby initiating de-coupling of said first steering column (102) from said second steering column (104) when said steering column de-coupling member (110) is pushed against said torque transmitting member (108) by said steering shaft (106).
5. The steering column assembly (100) as claimed in claim 4, wherein said steering column de-coupling member (110) is configured to deform due to shearing of said circumferential groove (110G) thereby causing deformation of said steering column locking member (112) to de-couple said first steering column (102) from said second steering column (104) when said first section (110F) and said second section (110S) of said steering column de-coupling member (110) come in engagement with the rear end (102R) of said first steering column (102) and the front end (104F) said steering shaft (106) respectively during frontal collision of said vehicle;
the rear end (102R) of the first steering column (102) is tapered;
the front end (104F) of the second steering column (104) is tapered; and
said steering column de-coupling member (110) is made of lighter material when compared to a material of said torque transmitting member (108).
6. The steering column assembly (100) as claimed in claim 2, wherein said steering column locking member (112) includes a first portion (112F) and a second portion (112S), wherein said first portion (112F) and said second portion (112S) are adapted to be externally mounted onto the rear end (102R) of said first steering column (102) and the front end (104F) of said second steering column (104) respectively via said plurality of lock bolts (114F, 114S) thereby connecting said first steering column (102) to said second steering column (104).
7. The steering column assembly (100) as claimed in claim 6, wherein said torque transmitting member (108) includes,
an elongated groove (108G) adapted to receive a bottom end of said plurality of lock bolts (114F, 114S) thereby allowing said steering column locking member (112) to be externally mounted onto the rear end (102R) of said first steering column (102) and the front end (104F) of said second steering column (104) respectively;
a first external spline section defined on a first portion (108F) of said torque transmitting member (108), wherein said first external splines is engaged with corresponding first internal spline section defined in the rear end (102R) of said first steering column (102); and
a second external spline section defined on said second portion (108S) of said torque transmitting member (108), wherein said second external splines is engaged with corresponding second internal spline section defined in the front end (104F) of said second steering column (104).
8. The steering column assembly (100) as claimed in claim 1, wherein said steering column assembly (100) includes a spring (116), wherein one end of said spring (116) is engaged with said universal joint (103) and another end of said spring (116) is engaged with said torque transmitting member (108).
9. A method (200) for restricting a movement of a steering column assembly (100) during a frontal collision of a vehicle, said method (200) comprising:
pushing, by a steering shaft (106), a steering column de-coupling member (110) against a torque transmitting member (108) when the steering shaft (106) receives impact energy during the frontal collision of the vehicle; and
pushing, by the steering column de-coupling member (110), an entirety of the torque transmitting member (108) into a first steering column (102) thereby initiating de-coupling of the first steering column (102) from a second steering column (104) when the steering column de-coupling member (110) is pushed against the torque transmitting member (108) by the steering shaft (106).
10. The method (200) as claimed in claim 9, wherein said method (200) includes,
deforming, by the steering column de-coupling member (110) causes deformation of the steering column locking member (112) thereby de-coupling the first steering column (102) from the second steering column (104) when a first section (110F) and a second section (110S) of the steering column de-coupling member (110) comes in engagement with a rear end (102R) of the first steering column (102) and a front end (104F) of the second steering column (104) respectively during the frontal collision of the vehicle,
wherein
the rear end (102R) of the first steering column (102) is tapered;
the front end (104F) of the second steering column (104) is tapered; and
the steering column de-coupling member (110) is made of a lighter material when compared to a material of the torque transmitting member (108).