GB2521671A - Articulated vehicle reverse assist billiard - Google Patents

Abstract

A hitch point 1 provided on a vehicle for towing a trailer or such-like is capable of moving in a sideways direction in order to assist in steering the towed trailer. Sideways movement of the hitch point is preferably under the control of the vehicle steering mechanism. In a preferred embodiment the hitch point is a fifth wheel 1 provided on the towing cab or tractor of an articulated lorry. Alternatively, the hitch point may be a towing ball provided on a car or similar for towing a caravan or trailer (see fig. 3). The hitch may be moved by hydraulically, pneumatically or electrically powered jacks 3. The moveable hitch and vehicle steering may include an electronic interface (not shown), with movement of the hitch occurring in adjustably variable proportion to actuation of the vehicle steering. The vehicle driver/operator may be provided with switch means (not shown) for switching movement of the hitch on and off, and for switching between automatic and manual movement modes.

Description

Articulated Vehicle Reverse Assist Billiard

Background

For the purpose of clarity with this Patent application, an articulated tractor unit and trailer are the example used in the description of how it works and how it solves a problem. The concept however applies to all articulated vehicles so the principles remain the same but the designs are different.

Therefore different examples of articulated vehicle Billiards are drawn separately.

A recognised difficulty when reversing an articulated tractor unit and trailer is the amount of space required by the tractor unit to change the force direction at the king pin to initiate a turn on the trailet Furthermore, small amounts of movement of the king pin are difficult to judge and make some manoeuvres difficult or impossible in confined spaces, e.g. narrow roads, around parked vehicles, etc. At this point in time the hitch point of articulated vehicles is a fixed point when the vehicle is in motion; a direct mechanical link which only allows rotational movement; preferably with no slack. Longitudinal movement of the hitch point is possible to accommodate trailer length and weight variations with the trailer stationary if the mechanism is fitted.

To overcome the difficulties mentioned above with reverse rnanoeuvres, the innovative solution is to move the whole hitch point laterally across the tractor unit chassis before and during the reverse manoeuvres thereby changing the direction of the force applied by the tractor unit to the king pin reducing the amount of conventional movement required.

A Billiard is a controlled transverse slider mechanism connected between the fifth wheel and the chassis, capable of changing the force direction without the need to reposition the tractor unit. The Billiard is controlled by the steering wheel when it is selected and creates new reverse manoeuvres for articulated vehicles while in reverse motion. The amount of transverse movement required is small in order to assist soft turns or straight reversing in confined spaces. A preferred automatic electrical control assistance is part of the solution so that the new manoeuvres are also made easier to complete.

Advantages Long straight manoeuvres in reverse and soft reverse turns can be achieved with the tractor unit steered wheels remaining virtually straight ahead and the Billiard changing the direction of the force required for the reversing manoeuvre before or during reverse motion.

An electronic interface automatically controlling the Billiard is the preferable option to achieve simpler reversing manoeuvres accurately.

The addition of electronic sensors enables an automatic reversing facility for articulated vehicles.

A Billiard reduces the need for repeated correction of the prime mover in relation to the trailer in a reversing procedure.

The vehicle requires less space for reverse manoeuvres.

The Billiard allows very small movements of the steered wheels to effect more controlled reverse manoeuvres.

Ease of use -control of the Billiard is maintained by the steering wheel therefore there is some accepted familiarity with the new fImctions.

Introduction to Drawings

Figure 1 shows an example of a Billiard fitted between the fifth wheel and chassis of an articulated tractor unit moved by a hydraulic jack.

Figure 2 shows an example of a Billiard fitted between the fifth wheel and chassis of an articulated tractor unit moved by preferably two electrically driven screw jacks.

Figure 3 shows an example of a Billiard capable of fitting to a standard tow bar mounting bracket for vehicles used to tow caravans, trailers, etc.

Drawings -Detailed Description

Figure 1 Shows an example of a Billiard consisting of an upper grease plate (2), a lower grease plate (4) and a hydraulic jack (3). These fit between the existing structure of a fifth wheel (1) and the vehicle chassis (5). Side guidance load rails are shown at (6).

Figure 1 illustrates a Billiard as an alternative way of changing the force on the hitch point of an articulated vehicle to produce more controlled reversing characteristics in less space. Instead of only using the steered wheels to change the direction of the force; hydraulics, an electric motor or pneumatics move the hitch points laterally across the tractor unit in sympathy and proportionally to the steered wheel direction. Figure 1 illustrates the hydraulic version of the major components. The centre locking of the Billiard is not shown to keep the clarity of the drawings, however a hydraulic lock formed by the jack is preferred as one of the two locks in this design.

Figure 2 Shows an example of a Billiard consisting of an upper grease plate (2), a lower grease plate (4) and electronic motorised screw jacks (3). These fit between the fifth wheel (1) and the vehicle chassis (5). Additional side guidance is shown at (6).

Figure 2 illustrates the Billiard powered by electric motorised screw jacks as opposed to hydraulics. The grease plate arrangement remains the same. The screw jacks form a positive lock when stationary and are one of two preferred methods used to maintain the centre lock position in this design.

Figure 3 Shows an example of a Billiard consisting of a tow hitch (1), a carriage (2), an electric motorised screw jack (3) and a structural housing which also acts as the side guidance (4).

Figure 3 illustrates the Billiard for small articulated vehicles (cars and caravans) incorporating an electric motorised screw jack connected through a carriage on rollers held within a structural housing. Electrical isolation of the screw jack forms the centre lock in this design.

Detailed Description

The preferred method of transverse movement is by making the upper moving part of the Billiard one of two greased plates (Figure 1 -Ref. 2 and 4). The greased plate is moved by a hydraulic jack (Figure 1 -Ref. 3) taking power from the power steering system controlled by an electronic interface. The greased plate is guided and held by side guidance rails which are preferably load bearing.

When a Billiard is fitted, the steering wheel operates two simultaneous methods of control over the change of direction at the hitch point. An electronic interface between the steering wheel and the Billiard using feedback loop potentiometers to report positions assists accurate manoeuvring.

Altering the direction of the force applied to the trailer when the tractor unit moves using a Billiard is controlled by the steering wheel position with switch options for different circumstances. In all designs the de-selection of reverse gear runs the Billiard to centre and mechanical locking is achieved.

A four position switch is preferably located in the cab. The four positions are (Billiard off) conventional manoeuvres.

(Manual bias) The driver can off-set the billiard to enhance a turn in a confined space.

(Auto) The Billiard mimics the steered wheel position proportionally.

(Electronic assist) The trailer mimics the tractor using electronic sensors controlling the billiard movement for straight line and soft turn reversing.

The sensitivity of the Billiard is adjustable electronically by the driver from the cab. Whilst the movement of a Billiard is relatively small it does not replace conventional steering but enhances it.

For safe operation, the Billiard can only move with reverse gear selected and other preferred safety protocols made: for example weight off fifth wheel electronically isolates Billiard switching and central lock remains engaged.

Cab switching described above must also be selected for the Billiard to unlock from centre.

The concept of laterally moving the hitch point using a Billiard works for every articulated vehicle, however the design needs to suit each application.

i.e. a car and caravan Billiard hitch will be different from an articulated lorry but the reversing effects will be similar. Separate drawings are included to cover the most common articulated vehicles.

The preferred option of using the steering wheel to control the Billiard is where substantial control is gained in soft manoeuvres. The amount of movement of the Billiard is preferred to be a proportion of the steered wheel movement and adjustable by the driver from the cab.

Lateral force change using a Billiard reduces the required space for articulated reversing and allows manoeuvres that up until now have been considered impossible.

Claims (5)

1. Claims 1. A Billiard is a transverse sliding mechanism connected between the chassis and the tractor unit hitch point (fifth wheel) which moves the whole hitch point (fifth wheel and trailer king pin) laterally over the centre of the tractor unit chassis relative and proportionally to the steered wheel position.
2. 2. A Billiard allows two separate forms of reverse steering simultaneously controlled by the steering wheel.
3. 3. The unlocked position of the Billiard is controlled by an electronic interface between the Billiard and the steered wheels position allowing lateral movement to change the applied directional force of the tractor unit to the articulated trailer before and during reverse motion.
4. 4. The electronic interface which controls the Billiard position relative to the steered wheels position allows the vehicle steering wheel to remain in overall control.
5. 5. Proportional, directional force changes to the hitch point by the Billiard reduce the amount of steered wheel movement required.