GB2457244A

GB2457244A - Steering wheel with pivotable rim

Info

Publication number: GB2457244A
Application number: GB0802137A
Authority: GB
Inventors: Kimmo Tapani Wihinen
Original assignee: Valtra Oy AB
Current assignee: Valtra Oy AB
Priority date: 2008-02-06
Filing date: 2008-02-06
Publication date: 2009-08-12
Also published as: WO2009098559A1; GB0802137D0

Abstract

A steering wheel assembly has a rim 25 pivotably mounted to a single spoke or shaft 28. The spoke may have a bore 30 at one end, a narrowed portion of the rim passing through the bore such that the rim can be pivoted about the bore, for example over the top of the shaft to rest on the dashboard (figure 4), but rotating the rim of the wheel rotates the shaft 28 and thus a hub 35 in turn rotating a steering column. A locking device 40 may be provided so that the rim can only be pivoted about the pivot point 30 when the button 40 is actuated, and/or the spoke is in a desired location e.g. vertical. The assembly may be mounted in a utility vehicle having a rotating seat (16, figure 1) and secondary controls (14, figure 1).

Description

STEERING WHEEL ASSEMBLY

The invention relates to a steering wheel assembly suitable for the directing of steerable wheels on a wheeled vehicle.

Tractor cabs typically comprise an operator's seat mounted to a cab floor. Located in front of the operator's seat there is disposed a dashboard unit upon which is mounted a steering wheel.

The steering wheel serves to provide a user interface with the operator to allow control of the movement of the steerable wheels conventionally located at the ends of a front axle of the vehicle. Movement of the steering wheel is transmitted to the steering system by a control system which generally comprises a combination of mechanical, hydraulic and electronic components for example.

It is an object of the invention to provide an improved steering wheel assembly.

In accordance with the present invention there is provided a steering wheel assembly comprising a rim connected to a rotatable steering shaft by a single spoke wherein the rim is pivotally connected to the spoke.

By providing a pivotal connection at the periphery of the steering wheel the operator can simply and conveniently pivot the steering wheel to a stowed position, thereby increasing the available space to move within the cab. This is particularly advantageous when the operator's space within the vehicle is limited. For example, the operator can fold the steering wheel over to the stowed position when exiting the cab of a tractor.

The spoke preferably comprises a bore through which the rim passes, and in which the rim can freely rotate. This delivers a simple mechanical solution to providing the pivotal connection between the steering wheel and the spoke.

The steering wheel assembly preferably comprises releasable locking means to prevent pivotal movement between the rim and the spoke. The locking means may, for example, comprise a locking pin which can be disengaged by the operator to allow the rim to be folded into the stowed position. Preferably still the locking means is only releasable when the spoke is orientated at an angle within a predetermined range. For example, the locking means may be arranged to only release when the steering wheel is set substantially straight. This range may correspond to a substantially vertical position for the spoke thereby allowing the steering wheel rim to be folded into the optimum position when stowed.

In a preferred embodiment of the invention a utility vehicle such as a tractor is provided with a steering wheel assembly as described above. Known tractor cabs are typically provided with numerous user interfaces such as banks of levers and instrument panels. This often results in a very restricted working space for the operator. The steering wheel assembly in accordance with the invention delivers valuable and useful space saving in the working environment.

The utility vehicle may also comprise a seat which is rotatable on a base between a first operating position and a second operating position, wherein the assembly is provided in a position corresponding to the first operating position. Such a rotating seat set up is known in utility vehicles which require the operator to work at a position away from the main dashboard for long periods of time. For example, it is known to provide a second steering assembly at the rear of the vehicle cab which allows the operator to steer the vehicle from a position 180° to the normal operating position. The invention involves the recognition that free rotation of a standard seat is restricted by the conventional positioning of a steering wheel. By simply folding the steering wheel to a stowed position in accordance with the invention a standard seat can be employed on the rotating platform.

Further advantages will become apparent when reading the following description of specific embodiments of the invention with reference to the drawings in which:-Figure I is a schematic sectional view of a tractor cab provided with a steering wheel assembly in accordance with one embodiment of the invention; Figure 2 is a perspective view of the steering wheel assembly of Figure 1 showing the rim in the normal operating position; Figure 3 is a perspective view of the steering assembly of Figure 1 showing the rim in an intermediate pivoted position; and Figure 4 is a perspective view of the steering wheel assembly of Figure 1 showing the rim in a fully stowed position.

With reference to Figure I a tractor cab referenced generally at 10 is provided with a first steering wheel assembly 12, a second steering wheel assembly 14 and a seat 16.

Referring now also to Figures 2 to 4, the steering wheel assembly comprises a dashboard unit 20 attached to the floor tray 22 of the tractor cab. The dashboard unit 20 provides a surface for other user interfaces such as displays and buttons corresponding to various functions of the tractor.

The steering wheel assembly 12 further comprises a rim 25 pivotally connected to a single spoke 28.

The pivotal connection 30 comprises a bore through a first end of the spoke 28. A narrowed part of the periphery of the rim 25 passes through the bore. The rim 25 can rotate within the bore.

The diameters of the bore and the rim are selected so as to only allow rotation movement within the bore whilst preventing the rim from sliding through the bore along its periphery.

The other end of the spoke 28 is fixably attached to a centre boss 35. Rotation of the centre boss causes a signal to be transmitted to a steering control system which in turn causes steerable wheels of the vehicle to turn correspondingly. The boss 35 may be connected to the steering control system (not shown) by mechanical or electronic means for example. It will be appreciated by the skilled person that in normal use rotation of the rim by the operator causes the boss 35 to rotate.

With reference in particular to Figure 2, the operator can release locking means be depression of a button 40 located on the spoke. Depression of the button 40 causes a locking pin (not shown) to disengage within the spoke from the rim concealed within the bore. This enables free pivoting of the steering rim 25 in a direction indicated by arrow 50 in Figure 3.

The rim 25 is flipped over the dashboard by a pivoting motion at joint 30 to a stowed position shown in Figure 4 wherein the rim can simply rest on the upper surface of the dashboard unit 20.

Advantageously this provides increased space within the cab for the operator to move.

The seat 16 is mounted on a rotating base 60 as shown in Figure I. The base is rotatably mounted to the floor tray 22 and is free to pivot on axis 62. By simple stowing of the steering rim 25 in accordance with the invention there is increased freedom to employ a conventional tractor seat 16 which can rotate on axis 62 without the rear of the seat catching on the steering rim 25. Therefore the operator can simply rotate his seat 16 to face a different operating position at an angle away from the dashboard unit 20. For example, the seat 16 can be simply rotated to face the rear of the tractor cab 10 so as to allow operation from the second steering wheel assembly 14 if desired.

The releasable locking means provided within the spoke 28 further comprises sensing means (not shown) to detect the orientation of the spoke relative to the dashboard unit 20. This works in conjunction with the button 40 to prevent releasing of the locking means when the spoke is outside a predetermined range such as 100 either side of vertical. Furthermore the locking means can be prevented from being released when the vehicle is in motion for safety reasons.

Claims

CLAIMS1. A steering wheel assembly comprising a rim connected to a rotatable steering shaft by a single spoke wherein the rim is pivotally connected to the spoke.
2. An assembly according to Claim I, wherein the spoke comprises a bore through which the rim passes and in which the rim can rotate.
3. An assembly according to Claim I or 2, further comprising releasable locking means to prevent pivotal movement between the rim and the spoke.
4. An assembly according to Claim 3, wherein the locking means is only releasable when the spoke is orientated at an angle within a predetermined range.
5. A utility vehicle provided with a steering wheel assembly according to any preceding claim.
6. A utility vehicle according to Claim 5, comprising a seat which is rotatable on a base between a first operating position and a second operating position wherein the assembly is provided in a position corresponding to the first operating position.
7. A steering wheel assembly constructed and arranged substantially as hereinbefore described with reference to, and as shown in the accompanying drawings.