WO1987006541A1

WO1987006541A1 - Trailer

Info

Publication number: WO1987006541A1
Application number: PCT/GB1987/000241
Authority: WO
Inventors: John Anthony Brian Dias
Original assignee: Mcgeown, Frank, James
Priority date: 1986-04-23
Filing date: 1987-04-09
Publication date: 1987-11-05
Also published as: AU7233287A; GB8708515D0; GB8609960D0; GB2189442A; GB2189442B

Abstract

A trailer for towing a vehicle comprises a towing member or bar (1) connectable at one end to a towing vehicle, the other end being pivotally connected to at least one elongate cross member extending either side of said towing member or bar (1), a pair of wheel support means (4) for supporting a pair of wheels of the vehicle to be towed, each of said wheel support means (4) having a ground-engaging wheel (5) connected thereto and being pivotally connected to said at least one cross member (3).

Description

TRAILER

The present invention relates to a trailer for towing a vehicle.

A vehicle which is road worthy can be towed by means of a tow rope provided that a driver is available both for the towed vehicle and for a towing vehicle. The driver of the towed vehicle is responsible for steering it.

Alternatively, a specially adapted towing vehicle can be provided with an arm which can be operated to engage a pair of road wheels on a vehicle to be towed and which can be hydraulically operated to lift those road wheels off the road so as to allow towing of the vehicle. In this case, that part of the arm which engages the vehicle wheels is allowed to pivot horizontally so that as the towing vehicle is steered the towed vehicle follows in its path.

A vehicle which has a standard type of ball hitch can be used in combination with a flat bed trailer having a tow hitch to tow another vehicle. However, both 2- and 4-wheeled trailers suitable for carrying large cars are expensive, awkward to manoeuvre and take up a great deal of space when not in use.

If an attempt is made to tow a vehicle by supporting two road wheels on a rigid 2-wheeled trailer, serious problems occur during cornering; the towed vehicle tends to continue in a straight line and tends to break away from and fall off the trailer. A rigid 2-wheeled trailer with a support centrally pivotally mounted thereon is an improvement, but such a construction is not very robust and the use of a single central pivotal support makes such a trailer rather unstable under load. It is accordingly an object of the present invention to provide a trailer for towing a vehicle, in which the trailer is steerable and stable under load.

The present invention provides a trailer which can be hitched to a towing vehicle and which is designed to carry. a pair of road wheels of a vehicle to be towed, the trailer having a pair of trailer wheels interconnected and attached to a towing member or bar by pivotally coupled cross members in an arrangement such that the trailer wheels are steered by the towing member or bar to follow the path of a towing vehicle.

According to an aspect of the present invention there is provided a trailer for towing a vehicle comprising an elongate towing member or tσw bar connectable at one end to a towing vehicle, the other end being pivotally connected to at least one elongate cross member extending either side of said towing member or tow bar, a pair of wheel support means far supporting a pair of wheels of a vehicle to be towed, each of said wheel support means having a ground-engaging wheel connected thereto and being pivotally connected to said at least one cross member.

In accordance with a preferred embodiment, the trailer of the invention can be dismantled when not in use and can accordingly be stored in compact form.

Whilst reference has been made to at least one elongate cross member, in accordance with a preferred embodiment of the invention a pair of cross members, extending parallel to one another, would be utilised. In such situation, such pair of cross members would preferably be pivotally connected at their mid points at spaced locations along the length of the towing member or tow bar. In a preferred embodiment, the lengths of the or each cross member can be varied so as to suit vehicles of different widths. In this connection, each cross member would usually be made of a selected length corresponding to the minimum width of a vehicle to be towed and the length of each cross member could be extended by a sliding interconnecting hollow section, with locking pins to secure each cross member.

Each wheel support means is preferably in the form of a hollow rectangular frame, a portion of a respective wheel of a vehicle to be towed, in use, extending into the interior of the frame. Once such wheel portions are engaged in said wheel support means, additional securing means, suitably in the form of webbing, straps or the like, are utilised to securely locate the towed vehicle in position.

In order to engage a portion of the wheels of a vehicle to be towed in the respective wheel support means of the trailer of the invention, suitable ramp means would be utilised, possibly in association with winch means.

A suitable pulley arrangement should be utilised so as to enable the towed vehicle to be removed from the trailer when the towed vehicle has reached its desired location.

The towing member or tow bar may be constructed of interconnecting sections so as to enable its length to be varied, as well as enabling easy dismantling and compact storage to be effected.

The pivotal connections between the towing member or tow bar and the at least one cross member, as well as that between the at least one cross member and the pair of wheel support means, is preferably formed by removable bolts or pins passing through apertures in attachment means on the wheel support means and the or each cross member. Such arrangement, together with the preferred arrangement of the cross members and towing members being constructed of interconecting sections, disassembly thereof being effected by suitable removal of pins, enables the trailer, when not in use, to be dismantled easily and to be stared in compact form.

In an embodiment of the present invention, the trailer can be adapted for use as a 4-wheeled trailer. In this connection, the additional trailer means comprises a pair of wheel support means for supporting the rear wheels of a vehicle to be towed, each steel support means having a ground-engaging wheel connected thereto, said pair of wheel support means being connected to at least one elongate cross member and the or each cross member being pivotally connected to the at least one elongate cross member utilised in connection with supporting the front wheels of the vehicle to be towed. There is no need for the rear pair of wheel support members to be pivotally connected to the rear at least one cross member.

The present invention will be further illustrated, by way of example, with reference to the accompanying drawings,in which:

Fig. 1 is a schematic plan view of a trailer in accordance with the invention;

Fig. 2 is a schematic plan view of the trailer of Fig. 1 in en alternative position;

Fig. 3 is a schematic plan view of a disassembled trailer according to the invention; and

Fig. 4 is a plan view of a trailer in accordance with the invention adapted as a 4-wheeled trailer.

The trailer shown in Fig. 1 comprises an elongate towing member or tow bar 1 provided with a tow hitch 2, a pair of cross members 3, a pair of supports 4 for the road wheels of a vehicle to be towed and a pair of trailer wheels 5 attached to the supports 4. The couplings or connections 6 between the ends of cross members 3 and the supports 4 allow pivotal movement in a horizontal plane. The pivot pins 6 are not removable, only the pins at the interconnecting sections are removable so as to increase or decrease the track width to suit the vehicle to be towed. The cross members 3 are also pivotally coupled or connected 7 at their mid points at spaced locations along the length of the towing member 1.

The effect of the interconnection of the supports 4 by the rigid members 3 is that the couplings or connections 6 define a parallelogrammic frame whose sides are of predetermined length but whαse angular geometry can be varied, i.e. skewed, by relative side to side movements about pivot points 7 of the towing member or bar 1. As the trailer wheels 5 are fixed to the supports 4, the effect of skewing the parallelogram is that the trailer wheels are always aligned in the direction of the towing member - i.e. the wheels are steered by the towing member - as shown in Fig. 2.

Thus, when the trailer is being towed, for example with the front rαad wheels of a car on the supports 4, as the towing vehicle turns the wheels of the trailer are steered by skewing of the parallelogrammic frame and the towed car follαws the path of the towing vehicle. In order that the towed vehicle does not resist the steering movement of the supports it is preferable that the front [steerable wheels] wheels of the towed vehicle be supported on the trailer and the steering is left free [i.e.unlocked]. Alternatively, a turn-table arrangement could be fixed in each support 4 to allow free turning of the trailer relative to non-steerable supported wheels.

In order thet a vehicle to be towed may be loaded onto the trailer, detachable ramps 8 may be used to lead up to the supports 4. There may be a winch 9 mounted on the towing member or bar 1 which may be used to draw a vehicle onto the trailer. When the road wheels of the vehicle to be towed are supported they may be secured by means of webbing, straps or other means [not shown]. By routing the winch cable through a pulley arrangement [not shown] at the rear of the trailer, the vehicle may subsequently be pulled off the trailer.

In the trailer illustrated the cross members and towing members are constructed of interconnecting sections as shown in Fig.3. The sections may be locked together and disassembled by removal of pins 12. This arrangement has the two-fold advantage that the trailer can be varied in width so as to suit vehicles of different sizes and also that the trailer can be dismantled easily and pivotted parts folded. This allows the trailer to be reduced to compact form when not in use for towing and to be carried in a vehicle such as a rescue truck or van. Various inserts or crass pieces may be attached to the supports 4 so as to safely accommodate various wheel sizes.

The trailer wheels may be enclosed in trailer body work, or may be provided with mudguards 10 as shown.

If the trailer is being towed without any load it is preferable to prevent skewing. This can simply be achieved by forming one of the cross members with a leg 13 at the pivot point which can be locked in alignment with the towing member or ber 1 by means of a locking pin 11.

The embodiment illustrated in Fig. 4 is a plan view of a trailer in accordance with the present invention adapted for use as a 4-wheeled trailer.

The front portion of the trailer is in accordance with the embodiment illustrated in Figs. 1, 2 and 3. The additional rear trailer portion is generally referenced 14. This rear portion comprises a pair of cross members 15, a pair of supports 16 for the rear wheels of a vehicle to be towed and a further pair of trailer wheels 17 sttached to the supports 16. The rear portion is connected to the trailer for supporting the front wheels of a vehicle by means of an elongate member 18 which is pivotally connected at 19 to the towing member or bar 1 at the centre line of the twα cross members 3. In this embodiment, there is no need for pivotal movement of the rear section to tske place since the rear wheels of the vehicle are not required to move.

With the arrangement illustrated in Fig. 4, the front wheels and the rear wheels of the vehicle would be inserted into respective supports 4 end 16 by means of ramps. Once located therein, the wheels would be secured to the supports.

It csn thus be seen that the trailer in accordance with the present invention provides a towing trailer which is both steerable and stable. Moreover, in view of the fact the trailer is formed of pivotally interconnected components,same can be easily disassembled for transport and compact storage. Hαwever, it can be understood that the present invention is also applicable to all types of framed trailers. It is to be noted that a lever type system could be operated in connection with removal of the wheels of the vehicle from the supports therefor, once the vehicle has reached its required destination.

Also, it is tα be understood that the trailer of the present invention could have associated therewith an appropriate braking system which would be operable by the driver of the towing vehicle in similar manner of operation to that of existing trailered vehicles. Also, an appropriate suspension system could also be included.

Whilst the embodiment illustrated in the drawings shows the supports 4 being pivotally connected to the members 3 at 6, it is to be understood that the position αf the pivots can be altered along the length of the members 3. In this connection, and to obtain maximum steerability and stability, the pivotable connection should be at different points along the respective cross members so that, on drawing a line passing through such two pivotable connections for each support, such lines intersect at roughly the centre line αf the rear axle αf the vehicle being towed, an optimum position being found to cater for the variable lengths αf vehicles likely tα be towed thus minimising tyre wear. It is to be understood that the trailer in accordance with the present invention can be utilised in connection with transport αf various types αf vehicles. Moreover, there is no need for a person to be located in the vehicle being towed. Accordingly, the trailer of the invention has anticipated uses ωhen transporting vehicles which have broken down and when transporting vehicles from one site to another. In addition, the 4-wheeled trailer embodiment in addition to being utilised for the purposes given above, could also be utilised in the transportation of racing cars and the like or vehicles of unroadworthy condition. It is also envisaged that, by suitable modification of caravans, whereby same would have a 4-wheel chassis, it mould be possible for the trailer of the present invention to be utilised in the transport of caravans.

It is also envisaged that the trailer arrangement in accordance with the present invention, particularly the 4-wheeled trailer, could be utilised for the transport of a car behind a larger vehicle, e.g. e mobile home or caravanette type of vehicle. In this arrangement, when the destination point has been reached, rather than conducting travel in a small area around such destination in the large vehicle, such travel can be effected in the smaller vehicle.

It is to be noted that the weight of the vehicle being towed when applied through the supports causes the trailer to adopt a steerable and stable condition. By the pivotal connection arrangement supplied, the trailer wheels are steered by the towing member to follow the path of the towing vehicle.

It is to be understood that the trailer would be equipped with lighting equipment to comply with public highway requirements, said equipment being operable by the towing vehicle.

It is also to be noted that when the trailer of the invention is unhitched from the towing vehicle, it is possible for the user to manually manoeuvre the vehicle located on the trailer into the desired position, and thereafter the vehicle is removed from the trailer.

Claims

1. A trailer which can be hitched to a towing vehicle and which is designed to carry a pair of road vehicles of a vehicle to be towed, the trailer having a pair of trailer wheels interconnected and attached to a towing member or bar by pivotally coupled cross members in an arrangement such that the trailer wheels are steered by the towing member or bar to follow the path of a towing vehicle.

2. A trailer for towing a vehicle comprising an elongate towing member or tow bar connectable at one end to a towing vehicle, the other end being pivotally connected to at least one elongate cross member extending either side of said towing member or tow bar, a pair of wheel support means for supporting a pair of wheels of a vehicle to be towed, each of said wheel support means having a ground-engaging wheel connected thereto and being pivotally connected to said at least one cross member.

3. A trailer as claimed in claim 1 or 2, in which a pair of cross members are utilised which are pivotally connected to the towing member or bar at their mid-points at spaced locations along the length of the towing member or bar.

4. A trailer as claimed in claim 3, in which each cross-member and the towing member are formed of internconnecting sections.

5. A trailer as claimed in any preceding claim in which each wheel support is in the form of a hollow rectangular frame.

6. A trailer as claimed in any preceding claim, in which the pivotal connections between the towing member or tow bar and the at least one crass member, as well as that between the at least one cross member and the pair of wheel support means, is formed by removable bolts or pins passing through apertures in attachment means on the wheel support means and the or each cross member.

7. A trailer as claimed in any preceding claim additionally including trailer portion for supporting the rear wheels of a vehicle to be towed.

B. A trailer as claimed in claim 7, in which the additional trailer portion comprises a pair of wheel support means, each wheel support means having a ground-engaging wheel connected thereto, said pair of wheel support means being connected to at least one elongate cross-member and the or each crass member being pivotally connected to the at least one elongate cross member utilised in connection with supporting the front wheels of the vehicle ta be towed.