Technical Field of the Invention

The present invention relates to steering system method and apparatus for motor vehicles and in particular for a modular steering assembly.

Background of the Invention

Steering systems are known within the automotive industry. Steering systems traditionally comprise a set of wheels, a steering gear, and a steering assembly. Structurally, the steering assembly is connected with the steering gear for controlling the position and angle of the wheels. To realize this purpose, a shaft encased by a steering wheel is included in the steering assembly. This shaft, which is coupled to the steering gear, extends through the interior of the vehicle body from a position above the floor where the driver seat is situated. The shaft may be rotated radially in the axial direction to cause the steering gear, and therefore the wheels, to change direction. Although the shaft is allowed to rotate, the steering column remains stationary relative to the motion of the motor vehicle body.

The steering system also comprises additional components each of which must remain stationary to couple the steering column and enclose the shaft. To facilitate the connection between the steering column and these other parts, the shaft extends farther into the interior of the vehicle than the steering column. The extension of the shaft is required because the desired final configuration of the steering assembly results in the shaft extending as far into the interior of the vehicle as the stationary parts of the steering

assembly. Therefore, these stationary parts will be connected to the steering column and cover the shaft.

One stationary component of the steering system is a multifunction switch. The multifunction switch is connected to the steering column and is typically housed with at least one branch switch projecting from the circumference. A pathway is fashioned into the center of the multifunction housing for receiving the shaft. The diameter of the pathway allows for rotation of the steering wheel shaft without rotating the multifunction switch.

The multifunction switch contains several mechanisms for controlling various vehicle features, including windshield wiper controls, headlight controls, and blinker controls, for example. These control mechanisms are based within the housing or the branch switch of the multifunction switch. A connection passes through the stationary connection between the multifunction switch and the steering column, thereby sending signals received from inputs through the multifunction to the systems or controls of the vehicle.

Similar to the multifunction switch, the steering wheel also contains several functions and controls, including the horn, cruise control, and the air bag, for example. The input signals from these additional controls are initiated from the steering wheel and subsequently passed to the clockspring ribbon. Once at the clockspring ribbon, the input signals may be passed through the multifunction switch to the systems or controls of the vehicle.

Traditionally, the clockspring is located rearward in vehicle from the multifunction switch. The clockspring functions as a conductive connector for allowing the relative rotation between two components Comprising a ribbon situated within a stationary

housing, one end of the ribbon of the clockspring is fixedly coupled to the multifunction. The clockspring therefore receives inputs from one component and transfers those input signals to the multifunction switch.

Within the steering system, the steering wheel is attached to the end of the shaft.

The steering wheel typically comprises a ring having connected arms linked at the center of the ring to meet at an intersection, or hub. This ring is grasped by the driver of the vehicle and rotated to turn the wheels. The center of the hub is also coupled to and rotates the shaft such that the shaft and die ribbon are the sole connections to the steering wheel. Therefore, the steering wheel rotates without rotating the clockspring housing, the multifunction switch, or the steering column.

The process of assembling the steering system typically takes place in a vehicle production factory along a production line. A production line assembles the vehicle either one part at a time or one part, subsystem and/or system simultaneously, while the developing vehicle is moved from one production area to another. A vehicle that is ready to receive a steering system typically arrives at the production area for the steering system with the steering column and the shaft already positioned in the vehicle. A first step in the process of assembling the steering system is to add the multifunction to the steering system. The multifunction slides around the steering column and is joined structurally and electrically to the steering column.

After the multifunction switch is securely fastened to the steering column, the clockspring is connected to the steering system. Like the multifunction switch, the clockspring is placed around the shaft. The housing component of the clockspring may be joined to either the multifunction switch or the steering column and secured. One end

of the clockspring ribbon may also coupled to the multifunction switch. The last step in assembling the steering system is to connect the steering wheel and airbag to the shaft and the ribbon.

Other methods of assembling steering systems are sought and it is to this end that the present invention is directed.

Summary of the Invention

The primary advantage of the present invention is to overcome the limitations of the prior art.

Another advantage of the present invention is to provide a test for the steering system before the system is assembled onto the shaft and steering column.

A further advantage of the present invention is to reduce the time needed for the producer of vehicles to assemble the steering system.

Still a further advantage of the present invention is to reduce the number of parts needed to be assembled on the production line.

Yet still another advantage of the present invention is to reduce the size of the steering system.

In order to achieve the advantages of the present invention, a modular steering assembly is disclosed. The modular steering assembly comprises a steering wheel and a multifunction system having a plurality of input controls. The multifunction system

comprises a housing, a rotational to non-rotational electrical connection attached to the housing, and a rotating plate connecting to the rotational to non-rotational electrical connection for engaging with the steering wheel.

In order to achieve the advantages of the present invention, a method is also disclosed for assembling a modular steering assembly. The method comprises the step of coupling a steering wheel to a multifunction system. Once the steering wheel is coupled to the multifunction, the multifunction system is mounted to the steering column shaft. Subsequently, the multifunction system is electrically coupled to the steering column and the steering wheel is engaged to the steering column shaft.

These and other objects, features and advantages of the present invention will become more apparent in light of the following detailed description of an exemplary embodiment thereof as illustrated in the accompanying drawings.

Brief Description of the Drawings

The present invention will be better understood from reading the following description of non-limitative embodiments, with reference to the attached drawings, wherein below:

FIG. 1 is a cut-away view of a steering system of the present invention;

FIG. 2 is a perspective view of the steering system of the present invention;

FIG. 3 is an exploded view of a multifunction system of the present invention;

FIG. 4 is a perspective view of an alternative embodiment of the multifunction system of the present invention;

FIG. 5 is a perspective view of a steering wheel of the present invention;

FIG. 6 is an isometric view of a hub of the present invention;

FIG. 7 is an exploded view of the steering system of the present invention;

FIG. 8 is a perspective view of the multifunctional system of the present invention; and

FIG. 9 is a perspective view of an alternative embodiment of the attachment methodology of the present invention.

It should be emphasized that the drawings of the instant application are not to scale but are merely schematic representations and are not intended to portray the specific parameters or the structural details of the invention, which can be determined by one of skill in the art by examination of the information herein.

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Referring to FIG. 1, a vehicle 20 is depicted having a pair of front and a pair of rear wheels 23 and 26. A steering gear 29 is aligned between the front wheels 23 and is employed to control the direction of the vehicle 20. A shaft 32 extends from the steering gear 29 into the interior of the vehicle 20 at a position above the floor where a driver 35 of the vehicle 20 is seated. A steering column 38 is fixed to the body of the vehicle 20

and encases the shaft 32. The steering column 38 is therefore fixed relative to the motion of the vehicle 20, but the shaft 32 is free to rotate radially in the axial direction within the steering column 38.

Vehicle 20 comprises a modular steering assembly 41 having a multifimction system 44 and a steering wheel 47. The multifunction system 44 may be the stationary part of the modular steering assembly 41, and is coupled electrically and structurally to the steering column 38. A number of conventional means used for attaching the multifunction system 44 to the steering column 38 may be practiced and are readily known in the art. The multifunction system 44 surrounds the shaft 32, but yet does not rotate with the shaft 32.

The steering wheel 47 is coupled electrically to the multifunction system 44 and structurally to the shaft 32, as detailed hereinbelow. The steering wheel 47 is therefore allowed to rotate with the shaft 32 while relaying inputs to and from the stationary multifunction system 44. FIG. 2 depicts the final structure of the shaft 32, the steering column 38 and the modular steering assembly 41 in relationship to the driver 35 of the vehicle 20.

Referring to FIG. 3, the multifunction and the clockspring system 44 are illustrated in greater detail. Both the multifunction system and clockspring system 44 are integrated. Further, multifunction system and clockspring system 44 comprise a housing 50 with an integral tubular shell 53 on a facing 54 of the housing 50.

Moreover, a pathway 56 is fashioned substantially central to the multifunction system 44 to enable the shaft 32 to pass through. The pathway 56 penetrates the multifunction system 44 through the tubular shell 53 and the housing 50. The dimension of the pathway 56 allows rotation of the shaft 32 without rotating the multifunction system 44.

The multifunction system and clockspring system 44 contains several controls. Witiiin the automotive industry it is intended that these controls be within the arm's reach of the driver. Windshield wiper controls, headlight controls, and turn signal controls are examples of a few of the inputs that may be based within the multifunction system 44.

These controls are preferably located on a branch switch 59 that extends from a side of the housing 50. More than one branch switch 59 may be positioned on the housing 50 depending on the number of controls desired. Additionally, a device is incorporated for canceling the turn signal may be realized by mechanical, electro-mechanical, or electronic means.

Stationed within the tubular shell 53 of the multifunction system 44 is a rotational to non-rotational electrical conductor or clockspring ribbon 62. The rotational to non- rotational electrical conductor 62 allows relative rotation between two components. The preferred realization of a rotational to non-rotational electrical connection is a clockspring. In the preferred embodiment, one end of the clockspring ribbon 62 is coupled to the multifunction system 44. This end of the clockspring ribbon 62 is fixed and does not move. The other end of the clockspring ribbon 62 is conventionally connected to and rotates with the steering wheel 47. The clockspring ribbon 62 therefore transmits inputs from the steering wheel 47 to the multifunction system 44, or other vehicle systems.

Stationed adjacent to the clockspring ribbon 62 within the tubular shell 53 is a rotating plate 65. The rotating plate 65 is circular and contains an aperture 66 in the center of a planar surface 67 for receiving the shaft 32. The clockspring ribbon 62 is joined with an inner planar face 68 of the rotating plate 65. The clockspring ribbon 62 relays the electric pulses between the housing 50 and the rotating plate 65.

A receptacle 69 is attached to the outer planar face of the rotating plate 65. A plurality of receptacles 69, however, are preferred to one receptacle for attaching to the rotating plate 65 and for engaging with the steering wheel 47. As the rotating plate 65 is engaged with the steering wheel 47, the rotating plate 65 rotates in register with the steering wheel 47. A hole 71 is located through each receptacle 69 in the axial direction. Positioned along a lip 72 of the tubular shell 53 of the multifunction system 44 are a plurality of slots 74. The holes 71 in the receptacles 69 are aligned with the slots 74 in the tubular shell 53. A line can therefore be placed through at least one of the holes 71 and two of the slots 74. Some of the holes 71 will also be aligned with another hole 71 in another receptacle 69.

Referring to FIG. 4, an alternative configuration is shown for the rotating plate 65 and the tubular shell 53 of the current invention. Here, one of the receptacles 69 is replaced on the rotating plate 65 by a semicircle receptacle 80. A plurality of notches 83 are arranged around the Up 72 of the tubular shell 53. A latch 86 is disposed between the semicircle receptacle 80 and one of the notches 83. The midpoint of the latch 86 is secured to a shoulder 87 which protrudes from the rotating plate 65 and allows the latch 86 to pivot. A spring 88 is located on the shoulder 87 coupling the latch 86 to the shoulder 87. One end of the latch 86 lies within the semicircle of the semicircle receptacle 80 and the other end of the latch 86 rises above the lip 72 of the tubular shell 53.

Referring to FIG. 5, the steering wheel 47 id depicted engaging with the rotating plate 65 of the multifunction system 44. The steering wheel 47 comprises a ring 89 with a plurality of connected arms 92 linked at the center forming a armature 95. The ring 89 is grasped by me driver 35 of the vehicle 20 and is usually rotated to turn the front wheels 23. A stud 98 is positioned on the armature 95 opposed to the rotating plate 65. A plurality of studs 98, however, are preferably positioned on the armature for aligning and engaging with the receptacles 69 located on the rotating plate 65. The outer diameter of the studs 98 are substantially the same length as the diameter of the receptacles 69, allowing for tolerances for fit. A hub 101 for coupling the steering wheel to the shaft is employed to join the steering wheel 47 to the shaft 32 is positioned substantially centrally on the surface of the armature 95 opposed to the rotating plate 65. Similar to the multifunction system 44, the steering wheel 47 contains several functions and controls accessible to the driver 35 of the vehicle 20. The horn, cruise control and air bag are examples of the inputs that can be based on the steering wheel 47.

Referring to FIG. 6, the armature 95 of the steering wheel 47 is illustrated. The studs 98 are positioned on the armature 95. In an alternative embodiment, studs 98 are part of the trim covering attached to armature 95. An orifice 104 is located in each stud 98 in the axial direction and are aligned with the holes 71 in the receptacles 69 and the slots 74 in the tubular shell 53. A line may therefore be drawn from one of the slots 74 in the tubular shell 53 through the hole 71 in the receptacle 69 through the orifice 104 in the stud 98 and through another slot 74 in the tubular shell 53.

Referring to FIG. 7, the method of assembling the modular steering assembly 41 is illustrated. Here, the clockspring ribbon 62 and the rotating plate 65 is deposited into the tubular shell 53. In one embodiment of the present invention, clock spring and multifunction system 44, and the tubular shell 53 are integral with the housing 50.

Subsequently, the studs 98 are engageably positioned on the armature 95 of the steering wheel 47 with the receptacles 69 of the rotating plate 65. A keeper 107 is engaged with the slots 74 of the tubular shell 53, the holes 71 of the rotating plate 65 and the studs 98 of the armature 95 forming a line through the slots 74, the holes 71 and the studs 98. The keeper 107 is preferably an U-shaped pin. A number of other configurations for the keeper 107, including a linear pin, may be practiced and would be apparent to one of ordinary skill in the art. The connections (not shown) between the multifunction system 44 and the steering wheel 47 are engaged through a sequential system consisting of the clockspring ribbon 62 and the rotating plate 65. As such, the multifunction system 44, the clockspring ribbon 62, the rotating plate 65 and the steering wheel 47 are mechanically and electrically coupled.

The modular steering assembly 41 comprising the multifunction system 44 and the steering wheel 47 is slid around the shaft 32 and is joined structurally and electrically to the steering column 38. The multifunction system 44 preferably snaps onto the steering column 38, or is otherwise coupled. The keeper 107 is then removed from the multifunction system 44, the clockspring ribbon 62, the rotating plate 65 and the steering wheel 47.

In an alternative embodiment the steering wheel 47 and the multifunction system

44 are coupled to form the modular steering assembly 41 such that the multifunction system 44 may be assembled and joined to the steering column 38 before the multifunction system 44 is coupled with the steering wheel 47. FIG. 8 depicts a multifunction system 44 that is not coupled with the steering wheel 47. After the clockspring ribbon 62 and the rotating plate 65 are deposited into the tubular shell 53, the keeper 107 is engaged with the slots 74 of the tubular shell 53 and the holes 71 of the rotating plate 65 forming a line through the slots 74 and the holes 71. The multifunction system 44 is then slid around the shaft 32 and joined structurally and electrically to the

steering column 38. The multifunction system 44 preferably snaps onto the steering column 38, or is otherwise coupled.

The receptacles 69 stationed on the rotating plate 65 are prepared for reception of the steering wheel 47 by removing the keeper 107 from the multifunction system 44, the clockspring ribbon 62 and the rotating plate 65. The multifunction system 44, the clockspring ribbon 62 and the rotating plate 65 should not rotate before the steering wheel 47 is coupled to the multifunction system 44. The steering wheel 47 is then slid around the shaft 32, and the studs 98 positioned on the armature 95 of the steering wheel 47 are engaged with the receptacles 69 of the rotating plate 65. The modular steering assembly 41 in then coupled electrically to the steering column 38.

Referring to FIG. 9, a locking mechanism is depicted. Here, the mechanism employs the latch 86 of FIG. 4. Preferably, the spring 88 located on the shoulder 87 of the rotating plate 65 biases the latch 84 into the notch 83 on the tubular shell 53. With the spring 88 locking the latch 84 into the notch 83, the multifunction system 44, the clockspring ribbon 62 and the rotating plate 65 will not rotate relative to each other.

Further, the multifunction system 44 is coupled to the vehicle 20 by sliding around the shaft 32 so as to engage structurally and electrically with the steering column 38. The multifunction system 44 preferably snaps onto the steering column 38. In the alternative, multifunction system 44 is coupled onto the steering column 38. The steering wheel 47 is then slid around the shaft 32 and the studs 98 positioned on the armature 95 of the steering wheel 47 are engaged with the receptacles 69 of the rotating plate 65. As shown in FIG. 9, when the studs 95 are engaged with the receptacles 69, the latch 88 preventing the rotating plate 65 from rotating is depressed. When the latch 88 is depressed, the latch 88 no longer engages with the notch 83 on the tubular shell 53, shown in shadow in FIG. 9. The steering wheel 47 and the rotating plate 65 are then free

to rotate. After the multifunction system 44 and the steering wheel 47 are positioned in the vehicle 20, the steering wheel 47 is coupled to the shaft 32 using means apparent to one of ordinary skill in the art.

While the particular invention has been described with reference to illustrative embodiments, this description is not meant to be construed in a limiting sense. It is understood that although the present invention has been described in a preferred embodiment, various modifications of the illustrative embodiments, as well as additional embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description without departing from the spirit of the invention, as recited in the claims appended hereto. Thus, for example, it should be apparent to one of ordinary skill in the art that while the present invention is intended for vehicles, it is also suitable in conjunction with steering systems in other applications. Similarly, it should be apparent to one ordinary skill in the art while the steering system of the present invention has been detailed as the steering assembly including the steering wheel and the multifunction system, other formats including the multifunction system individually, for example, are available which would take full advantage of the present invention. Moreover, while the present invention as detailed herein discloses a keeper for preventing the housing, the clockspring, the rotaring plate and the steering wheel from rotating relative to each other prior to vehicle assembly, it should also be apparent to one of ordinary skill in the art that the latch in the alternative may be realized by means of preventing rotation. Furthermore, while the present details invention as detailed herein discloses an integrated tubular shell and housing, it should also be apparent to one of ordinary skill in the art that the tubular shell may be coupled with the housing to form a modular unit. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention.