DESC:FIELD OF INVENTION

The present invention relates to cross car beam in motor vehicles and particularly the present invention relates to an optimized configuration of the cross car beam assembly which is light-weight, compact and thereby provides more cabin space.

BACKGROUND OF THE INVENTION

Normally, the Instrument Panel (IP) assembly of a motor vehicle is a complex structure, which is configured to accommodate several sub-systems, such as Cross car beam (CCB), Heating, Ventilation and Air Conditioning (HVAC) system and the like.

Out of these, cross car beam is the structural member providing support to these systems, such as Steering Systems, Instrument panel, HVAC module, Transmission shifter unit, Climate controls.

A cross-car beam is a structural component acting as a link between the A-pillars or side panel structures of a motor vehicle body. Basically, it imparts stiffness to motor vehicle body. It also provides a high torsional rigidity and improves crash test worthiness of the IP system. It provides a solid support to the steering wheel, steering column and transmission shifter unit, and also reduces vibrations.

Conventional Cross car beam shown in Figures 2a, 2b and 4a, 4b have reinforcing members disposed between the facing inner panels of the A pillar. However, in some cases, where the desired level of axial stiffness is not required, the implementation of such full CCB configuration undesirably adds weight to a vehicle.

Cross Car beam connects both ends of the inner panels of the Body-in-White (BIW) to impart torsional stability and thereby acts as the support structure to mount components such as IP, Steering column, HVAC unit and wiring harness.

For quadricycle type of motor vehicles, the pipe is required for only half the distance, because CCB needs to support mainly/only the steering column. One end of it is connected to BIW inner panel, while the other end is connected to dash panel/floor.

It is very challenging to meet strict Noise, Vibrations and Harshness (NVH) targets for small segment motor vehicles. Out of these requirements, the natural frequency of the cross car beam is one of the important parameters for tactile vibration. The conventional full-cross car beam configuration does not meet the targeted weight requirements.

The requirement of achieving the targeted CCB frequency without adding any extra weight is of utmost importance. Accordingly, there is a strong-felt need for increasing CCB frequency by reducing its weight.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide a cross car beam (CCB) in motor vehicles with a reduced overall weight of the vehicle without affecting the performance.

Another object of the present invention is to provide a short cross car beam assembly in vehicles with reduced number of brackets.

Still another object of the present invention is to connect the cross car beam to the least possible body structure of vehicle without affecting the performance.

Yet another object of the present invention is to provide a cross car beam which improves the NVH performance
A further object of the present invention is to provide more cabin space in the motor vehicle.

These and other objects and advantages of the present invention will become clearer from the following description, when read in combination with the accompanying figures of drawing.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a short cross-car beam (CCB) assembly for motor vehicles, the assembly comprising:

• a pipe to function as a cross-car beam (CCB);
• a steering column bracket mounted on the dashboard of the motor-vehicle; and
• A-pillar or side panel structure of the body-in-white (BIW);

wherein the CCB pipe is disposed between the steering column bracket and A-pillar or side panel structure and first end of CCB pipe is fixed on the inner panel of A-pillar or side panel structure and other end of the CCB pipe passes through the steering column bracket and circumferentially welded on the other side of the bracket.

Typically, the CCB pipe is configured straight.

Typically, the steering column bracket is configured of at least a pair of brackets disposed at a predetermined distance from each other and having a respective hole for passage of the CCB pipe through it for welding on the inner bracket.

Typically, the CCB pipe is profiled towards the dashboard to provide more cabin space for the motor-vehicle driver.

Typically, the steering column bracket is additionally supported on the motor-vehicle floor panel by means of a connecting member.

Typically, the steering column bracket profiled towards the motor-vehicle driver by using a single bracket for attachment to the steering column.

Typically, the natural frequency of the dash panel or floor-panel is determined by the equation:
_____________________
Natural Frequency, wn = ? [f (K1+ S1.K2 + S2) / m]

and
m? + f (K1+ S1.K2 + S2) x = 0

where, m is the mass of the system and K is the Stiffness of the system.

Typically, the CCB pipe is supported on the right hand side A-pillar or side panel structure in a Left-hand drive motor vehicle.

Typically, the CCB pipe is supported on the left hand side A-pillar or side panel structure in a Right-hand drive motor vehicle.

Typically, the motor-vehicle is a quadricycle type of motor-vehicle.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

The Cross Car Beam (CCB) in accordance with the present disclosure will now be described with the help of accompanying drawings, in which:

Figure 1a illustrates an isometric view of the new Cross Car Beam (CCB);

Figure 1b illustrates the new Cross Car Beam (CCB) fitted in the motor vehicle;

Figure 2a illustrates an isometric view in front of the driver in a conventional CCB configuration;

Figure 2b illustrates the top view of the conventional CCB configuration shown in Figure 2a;

Figure 3a illustrates a perspective view of the conventional CCB configuration;

Figure 3b illustrates a schematic representation of the conventional CCB with the A-pillar of the motor vehicle by means a Free-body diagram of the system;

Figure 4a illustrates the view in front of the driver in a CCB configuration in accordance with the present invention;

Figure 4b illustrates the top view of the CCB configuration shown in Figure 4a;

Figure 5a illustrates a perspective view of the CCB in accordance with the present invention showing its connection to the dash board and inner panels of A-pillar of the motor vehicle;

Figure 5b illustrates a schematic representation of the CCB configuration shown in Figure 5a by means a Free-body diagram of the system;

Figure 6a illustrates a perspective view of the of the CCB in accordance with the present invention showing its connection to floor panel of the motor vehicle;

Figure 6b illustrates a schematic representation of the CCB configuration shown in Figure 6a by means a Free-body diagram of the system;

Figure 7 graphically illustrates the comparison of the Vibration Transfer Function (VTF) plots both for the new half CCB configuration and conventional configuration;

Figure 8 graphically illustrates the comparison of Noise Transfer Function (NTF) RMS plots both for the new half CCB configuration and conventional configuration;

Figure 9 illustrates the first embodiment of short CCB configured in accordance with the present invention;

Figure 10 illustrates the second embodiment of the short CCB configured in accordance with the present invention;

Figure 11 illustrates the third embodiment of the short CCB configured in accordance with the present invention depicting the plots for CAE analysis at the system level; and

Figure 12 shows the fourth embodiment of short CCB configured in accordance with the present invention.

DETAILED DESCRIPTION OF ACCOMPANYING DRAWINGS

The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The preferred embodiments do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration only.

The main function of the CCB in accordance with the present invention is to support the steering column assembly. In such cases, one end of the CCB pipe is connected to the Front Body side inner panel, whereas the other end can be connected to the dash panel after steering column support, or one end can be connected to the side inner panel and the other end to the floor or both end to the dash panel. If the side inner panels are narrow in the driver zone it can be connected to either inner panels or any other mounting combination as mentioned above. The Main advantage of the present invention is the reduction in the CCB pipe length, which in turn leads to a considerable reduction in overall system weight.
Figure 1a illustrates an isometric view of the Cross Car Beam (CCB) assembly 50 in accordance with the present invention. It includes the first CCB end bracket 10, the Steering column bracket 20 and the CCB 30 and the second CCB end bracket 40. The Steering column bracket 20 is bolted to the CCB end bracket 10 and the connection between the Steering column bracket 20 and the CCB 30 is an arc welded joint 22 on both sides thereof.

Figure 1b illustrates the CCB in accordance with the present invention shown in Figure 1a, e.g. fitted on a BIW 60 of a typical motor vehicle. The figure shows the location 24 of the cross car beam assembly 50 and its connection to the different assemblies, e.g. steering column 26. A weight saving in the range of 20-50% is achieved by keeping the same performance parameters.

Figure 2a illustrates the view in front of the driver in a conventional CCB configuration for a motor vehicle. The cross-car beam is a structural component which connects A-pillars or side panel structures 28 of a motor vehicle body 60 to impart stiffness to motor vehicle body by increased torsional stability. Therefore, the CCB acts as a support structure for mounting components such as IP, Steering column, HVAC unit and wiring harness. The reinforcing members are also disposed between the facing inner panels of the A pillar. However, when the axial stiffness is not very crucial, such extra-long CCB (see the portion marked as 70) configuration unnecessarily increases the weight of the motor vehicle.

Figure 2b illustrates the top view of the conventional CCB configuration shown in Figure 2a. It can be seen here again, that the portion marked by 70 is undesirable and should be dispensed with for reducing the weight of the CCB assembly.

Figure 3a illustrates a perspective view of the conventional CCB configuration. CCB 30 is supported and connected at its two end brackets 40 with the inner panels 28 of the A-pillar (see Figure 2a) and steering column bracket 20. CCB 30 is also connected to the dash panel 80 for providing torsional rigidity thereto.

Figure 3b illustrates a schematic representation of the linkages of the conventional CCB with the A-pillar of the motor vehicle by means a Free-body diagram of the system. The relevant equations of motion for the conventional cross car beam are discussed subsequently with reference to the different stiffness K1, K2, K3 of the system in terms of the lengths l1, l2 and l3 of the system shown here. This calculation is essential for determining the natural frequency of the cross car beam.

Figure 4a illustrates the view in front of the driver in a half CCB configuration in accordance with the present invention. According to the new CCB configuration, the CCB pipe 130 is required for only half the distance for the quadricycle type motor vehicles. The CCB length is saved by almost half in this new configuration, which is marked by portion 90. Thereby, the targeted CCB frequency is achieved by the reduction in the weight of the CCB assembly due to a smaller length of the CCB pipe 130. This is achieved by making the CCB to mainly/only support the steering column 126 and by connecting one end thereof to the BIW inner panel 128 (see also Figures 5a and 5b). This way, the torsional rigidity or stability of the CCB assembly is ensured, however with a substantial weight reduction.

Figure 4b illustrates the top view of the half CCB configuration shown in Figure 4a, which also shows the saved CCB length marked by the portion 90.

Figure 5a illustrates a perspective view of the half CCB 130 in accordance with the present invention showing the connection thereof with the dash board 110 via steering column bracket 120 and with the inner panels 140 of the A-pillar of the motor vehicle.

Figure 5b illustrates a schematic representation of the linkages of the half CCB configuration shown in Figure 5a by means a Free-body diagram of the system. Here, CCB is connected to the dash board at a location 124 and to the BIW inner panel at the end bracket 140. As discussed in Figure 3b, the relevant equations of motion for the cross car beam in accordance with the present invention are discussed subsequently with reference to the different stiffness K1+S1 and K2+S2 of the system observed in terms of lengths l1 and l2 of the system for determining the natural frequency of cross car beam 130. Therefore, the natural frequency improves with an increase in the stiffness and reduction in the mass of the CCB assembly.

Figure 6a illustrates a perspective view of the half CCB 130 in accordance with the present invention showing the connection 160 thereof with the floor panel 155 of the motor vehicle and with the inner panel 140 of the A-pillar. Accordingly, a reduced length CCB 130 can be deployed, which not only reduces the weight of the CCB assembly, but also facilitates in creating more cabin space in the motor vehicle.

Figure 6b illustrates a schematic representation of the half CCB configuration shown in Figure 6a by means a Free-body diagram of the system. Here, the floor connection is provided at a location 158 and the A-pillar inner panel connection is via the end bracket 140. Again, the relevant equations of motion for the cross car beam in accordance with the present invention will be discussed in the following with reference to different stiffness K1+S1 and K2+S2 of the system observed in terms of lengths l1 and l2 thereof for determining the natural frequency of CCB 130.

Figure 7 graphically illustrates the comparison of the plots of Vibration Transfer Function (VTF) for the half CCB configuration in accordance with the present invention and the conventional CCB configuration. It is evident from this graph that half CCB 130 has lower response at the problematic frequency range.

Figure 8 graphically illustrates the comparison of the plots of Noise Transfer Function (NTF) RMS for the half CCB configuration in accordance with the present invention and the conventional CCB configuration. A significant improvement is observed around the problematic frequency band 4dB in the half CCB configuration according to the present invention.

Figure 9 illustrates the first embodiment of the short or half CCB configuration in accordance with the present invention. In this configuration, the short CCB pipe 230 is bent towards the steering column assembly. Accordingly, a single bracket is welded onto the pipe 230 for steering column assembly mounting, instead of the conventional method of welding multiple brackets.

Figure 10 illustrates the second embodiment of the short CCB configuration 330 in accordance with the present invention. The C channels of this embodiment of short CCB 330 is welded to act as a support framework for connecting the steering column support bracket 322 to the dash panel 310 of the motor vehicle. This has substantially lesser weight as compared to the conventional box type steering column support bracket.

Figure 11 of the present invention shows the third embodiment of short CCB configuration 430 having a central bracket arrangement 432 for steering support. CAE (Computer Aided Engineering) analysis of this short cross car beam 430 reveals that the first mode natural frequency at system level is increased by about 30%, when compared with the conventional configuration of the CCB.

Figure 12 shows the fourth embodiment of short CCB configuration in accordance with the present invention, which includes a support bracket 545 connecting one end of the CCB pipe 530 to the floor 555, while the other end is connected to the side panel or A pillar of the vehicle by means of the end bracket 540.

Equations of Motion:

a) For Conventional Cross Car Beam (CCB) –

m? + f (K1. K2) x = 0

wherein, m is the mass of the system and K is the Stiffness of the system.

_____________
Natural Frequency, wn = ? [f (K1. K2) / m]

b) For Short Length Cross Car Beam (CCB) of the Invention –

For Dash panel

m? + f (K1+ S1.K2 + S2) x = 0

wherein, m is the mass of the system and K is the Stiffness of the system.
_____________________
Natural Frequency, wn = ? [f (K1+ S1.K2 + S2) / m]

For Floor panel

m? + f (K1+ S1.K2 + S2) x = 0

wherein, m is the mass of the system and K is the Stiffness of the system.
_____________________
Natural Frequency, wn = ? [f (K1+ S1.K2 + S2) / m]

TECHNICAL ADVANCEMENTS AND ECONOMICAL SIGNIFICANCE

The technical advancements offered by the present disclosure include the realization of:

• This innovative CCB configuration meets the stringent frequency target values in the small segment vehicles.

• In addition to the frequency values being at par with the conventional CCB, this CCB configuration has an approximate weight saving of about 20% which also leads to substantial cost-reduction of the component, i.e. CCB assembly.

• Because of the lesser overhang of the components in the CCB configuration in accordance with the present invention, and since the natural frequency clears the road excitation frequency, better tactile vibrations result.

• In this CCB configuration, since the CCB is connected to only two sides (i.e. the RH side A-Pillar inner panel and dash panel); the time taken for the CCB assembly in this configuration is also substantially reduced.

• This new CCB configuration also helps in controlling the noise characteristics.

• No additional and/or complex manufacturing process is required obtaining for this CCB configuration.

• The compactness of the CCB configuration enable in providing more cabin space to the passenger in the motor vehicle.

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.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein.

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 preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention.

The exemplary embodiments described in this specification are intended merely to provide an understanding of various manners in which this embodiment may be used and to further enable the skilled person in the relevant art to practice this invention. The description provided herein is purely by way of example and illustration.

The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention. The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification.

Although the embodiments presented in this disclosure have been described in terms of its preferred embodiments, the skilled person in the art would readily recognize that these embodiments can be applied with modifications possible within the spirit and scope of the present invention as described in this specification.

A person skilled in the art may make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies and assemblies, in terms of their size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

While considerable emphasis has been placed on the specific features of the preferred embodiment described here, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiments without departing from the principles of the invention.

These and other changes in the preferred embodiment of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. ,CLAIMS:We claim:

1. A short cross-car beam (CCB) assembly for motor vehicles, the assembly comprising:

• a pipe to function as a cross-car beam (CCB);
• a steering column bracket mounted on the dashboard of the motor-vehicle; and
• A-pillar or side panel structure of the body-in-white (BIW);

wherein the CCB pipe is disposed between the steering column bracket and A-pillar or side panel structure and first end of CCB pipe is fixed on the inner panel of A-pillar or side panel structure and other end of the CCB pipe passes through the steering column bracket and circumferentially welded on the other side of the bracket.

2. Short cross-car beam (CCB) assembly as claimed in claim 1, wherein the CCB pipe is configured straight.

3. Short cross-car beam (CCB) assembly as claimed in claim 1, wherein the steering column bracket is configured of at least a pair of brackets disposed at a predetermined distance from each other and having a respective hole for passage of the CCB pipe through it for welding on the inner bracket.

4. Short cross-car beam (CCB) assembly as claimed in claim 1, wherein the CCB pipe is profiled towards the dashboard to provide more cabin space for the motor-vehicle driver.

5. Short cross-car beam (CCB) assembly as claimed in claim 4, wherein the steering column bracket is additionally supported on the motor-vehicle floor panel by means of a connecting member.

6. Short cross-car beam (CCB) assembly as claimed in claim 1, wherein the steering column bracket profiled towards the motor-vehicle driver by using a single bracket for attachment to the steering column.

7. Short cross-car beam (CCB) assembly as claimed in anyone of the claims 1 to 6, wherein the natural frequency of the dash panel or floor-panel is determined by the equation:
_____________________
Natural Frequency, wn = ? [f (K1+ S1.K2 + S2) / m]

and
m? + f (K1+ S1.K2 + S2) x = 0

where, m is the mass of the system and K is the Stiffness of the system.

8. Short cross-car beam (CCB) assembly as claimed in anyone of the claims 1 to 8, wherein the CCB pipe is supported on the right hand side A-pillar or side panel structure in a Left-hand drive motor vehicle.

9. Short cross-car beam (CCB) assembly as claimed in anyone of the claims 1 to 8, wherein the CCB pipe is supported on the left hand side A-pillar or side panel structure in a Right-hand drive motor vehicle.

10. Short cross-car beam (CCB) assembly as claimed in anyone of the claims 1 to 10, wherein the motor-vehicle is a quadricycle type of motor-vehicle.

Dated this 24th day of April, SANJAY KESHARWANI
APPLICANT’S PATENT AGENT