A dolly typically includes a base member for supporting articles to be transported, the base member being mounted at a relatively low level on a set of wheels. A handle may be provided for engaging the base member and allowing the dolly to be moved by pushing or pulling the handle. The handle typically engages a recess in the base member, being fitted into place by a"scooping" movement.

When the dolly is loaded relatively lightly or conveyed over a smooth, flat surface, manual movement of the dolly is quite satisfactory. However where the load is significant or the surface rough or sloping, it can be difficult or even impossible to move a dolly manually using its handle.

According to the invention there is provided a powered vehicle including connection apparatus for connecting the vehicle to a transportation device, the connection apparatus including: arm means for engaging in a recess of a first kind of transportation device; and catch means for engaging behind an elongate member of a second kind of transportation device.

Where the terms"horizontal"and"vertical"are used in this description, they refer to the situation where the vehicle stands on level horizontal ground.

Where the"front"or"rear"of the vehicle is referred to, the front of the vehicle is assumed to be that part which is nearer to the transportation device to be engaged.

The arm means may be for engaging in a recess of a dolly, to allow the powered vehicle to move the dolly.

The catch means may be for engaging behind a substantially horizontal bar of a roll cage, to allow the powered vehicle to move the roll cage.

Preferably the powered vehicle is able to receive a proportion of the weight of the roll cage when the catch means engages behind the bar of the roll cage.

Preferably the arm means is moveable between a first position in which it may enter and exit the recess in the dolly and a second position in which it may be firmly held within the recess. Preferably the arm means is biased towards the second position. The biasing means may include a resilient means such as a tension spring. Preferably the apparatus includes actuation means for overcoming the bias and moving the arm means into its first position.

Preferably the catch means includes a catch member moveable between a first position in which it may pass under the substantially horizontal bar of the roll cage, and a second position in which it is held in front of the bar of the roll cage, defining a recess in which the bar is retained. Preferably the catch means is biased towards the second position. The biasing means may include a resilient means such as a tension spring. Preferably the apparatus includes actuation means for overcoming the bias and moving the catch means into its first position.

Preferably movement of the catch means into its first position causes the arm means also to move into its first position. Alternatively, movement of the arm means into its first position may cause the catch means to move into its first position. Thus, a single actuation means may be provided for moving the arm means and the catch means into their respective first positions.

The arm means may include a pair of arms spaced apart. Each arm may be pivotally mounted on a support member, which may include a sheet metal plate. The arm may be mounted outwardly of the support member, and the pivotal mounting may be offset from a centre portion of the arm.

Each arm preferably includes a front distal portion including a rounded nose. Preferably in the arm's second position the nose may just enter an outer part of the recess in the dolly.

Preferably the nose represents the front of a ramped portion of the arm, the ramp extending upwardly and backwardly away from the nose. Preferably the ramp is so shaped that pushing of the nose into the recess in the dolly causes the ramped portion to pivot downwards, thus allowing it to enter the recess. The ramp preferably slopes at an angle of between 20° and 45° to the horizontal. A rear face of the ramped portion may slope backwardly at an angle of between 65° and 85° to the horizontal when the arm is in engagement with the recess. In such position, the rear face of the ramped portion is preferably able to engage a substantially vertical face of the dolly within the recess, the angle of the rear face allowing relative pivotal movement and enabling the dolly to be conveyed over uneven ground.

Preferably the ramped portion and nose are provided at the distal end of a relatively narrow neck portion, which may be about 5mm to 15mm, and preferably about lOmm, in the vertical dimension, the narrow neck portion enabling the arm to pivot within the recess in the dolly.

A rear portion of the arm, located behind the pivot point, may be of greater size in the vertical dimension than the remainder of the arm. This greater size may result in increased weight on the rear side of the pivot, thus biasing the arm into its second position.

The arm may include a central portion located between the neck portion and the rear portion.

The rear portion of the arm is preferably also biased downwardly by a spring. A member may link the rear portion of one of the arms to the rear portion of the other arm. An extension spring may be attached to this member and fixed at its other end relative to one of the support members. The bar may pass through elongate grooves in the support members.

A front portion of each arm may be wider in a substantially horizontal transverse direction than a rear portion of the arm. Each arm may include a main member including a ramped portion, neck portion, central portion and rear portion and an inner member including a ramped portion and a neck portion only. The inner members may be located to the inner sides of the main members, between the main members. The ramped portions and neck portions of the inner members may be of a similar but not identical configuration to those of the main members.

The catch member may be located generally between the two arms. A support member may be located between the catch member and each arm. The catch member may include a ramped front face sloping at an angle of between 30° and 60° to the horizontal. Preferably the ramp is so shaped that pushing of the catch member against the horizontal bar of the roll cage causes the catch member to move downwardly into its first position allowing it to pass under the horizontal bar. Once the catch member has passed under the horizontal bar preferably a spring biasing means causes it to spring back up into its second position. In this position the horizontal bar of the roll cage is preferably retained in a recess. The recess may be defined by a rear face of the catch member, by an upper face on each of the two support members, defining the base of the recess, and by a forward face on each of the two support members, defining the rear of the recess. The base of the recess is preferably able to bear a proportion of the weight of the roll cage when the horizontal bar is received in the recess.

The catch member may be provided with protrusions extending from the sides of the catch member. These protrusions may pass through openings in the support members. A protrusion preferably bears on an upper face of each arm, in a mid-portion thereof, such that downwards movement of the catch member into its first position pushes the arm into its first position.

Downwards movement of the catch member may be initiated by the actuation means. Preferably the catch member is moved by an actuating lever operated by tension in a cable. The cable preferably extends from the actuating lever to a handle provided on an upper part of the powered vehicle. Near the handle, the cable is preferably attached to a cam in the form of an eccentric circle which the cable can wrap around. Initial movement of the handle preferably causes the cable to wrap around a relatively small radius portion of the eccentric circle, with further movement of the handle causing the cable to wrap around a relatively larger radius portion of the eccentric cam.

An embodiment of the invention will be described for the purpose of illustration only with reference to the accompanying drawings, in which:- Fig. 1 is a diagrammatic perspective view of a connection apparatus for a vehicle according to the invention; Fig. 2 is a diagrammatic side view of the connection apparatus of Fig. 1 in engagement with a recess of a dolly; Fig. 3 is a diagrammatic side view of the connection apparatus of Figs. 1 and 2; Fig. 4 is a diagrammatic side view of an arm of the connection apparatus of Figs. 1 to 3; and Fig. 5 is a diagrammatic illustration of a cam arrangement for the connection apparatus of Figs. 1 to 4.

The figures illustrate a connecting apparatus 10 for a powered vehicle.

The powered vehicle may be generally as described in U. K. Patent Application No. GB 2334016.

Referring to Fig. 1, the connecting apparatus 10 includes a pair of arms 12 pivotally mounted on sheet metal mounting plates 14. Each arm 12 is mounted on a pin 16 at a position remote from its centre.

Each arm 12 includes a front distal portion 18 including a rounded nose 20. The nose 20 represents the front of a ramp 22 which extends upwardly and backwardly away from the nose 20. The ramp slopes at an angle of about 30° to the horizontal. A rear face 24 of the ramped portion 22 slopes backwardly at an angle of about 80° to the horizontal.

The ramp 22 and nose 20 are provided at the distal end of a narrow neck portion 26, which is about 10mm in its vertical dimension. Behind the neck portion 26 is a central portion 28 of the arm, which includes a raised substantially horizontal face 30, which has a function described below. Behind the face 30 is a cut-away portion 32, above the pin 16. Behind the pin 16 is a rear portion 34 of the arm. The rear portion 34 is of greater size in the vertical dimension than the remainder of the arm. This increased weight helps to counteract the increased length of the arm 12 on the opposite side of the pivot pin 16.

The rear portions 34 of each of the two arms 12 are linked by a bar 36.

The bar 36 passes through openings 38 provided in the sheet metal mounting plates 14. The openings 38 are elongated, such that some movement of the bar 36 is allowed. An extension spring 40 is attached to the bar 36 at one of its ends. The other of its ends is attached to a short bar 42 which is mounted on one of the sheet metal mounting plates 14. Thus the spring 40 biases the bar 36 downwardly as illustrated in Fig. 1. This biases the rear portion 34 of each arm 12 downwardly, thus biasing the nose 20 and neck portions 26 of the arms upwardly.

At its distal end, each arm includes an inner member 44 having a nose 46, ramped portion 48 and neck portion 50. The nose, ramp, and neck portions of the inner member 44 have a similar, but not identical configuration to the corresponding portions of the remainder of the arm. The corresponding portions of inner member are located somewhat lower than those of the remainder of the arm. This provides for engagement with the recess of a dolly over a wide area, providing a good contact area for the transmission of force from the powered vehicle to the dolly.

The connection apparatus 10 also includes a catch member 52 located generally between the arms 12. A sheet metal mounting plate 14 is located between the catch member 52 and each arm 12. The catch member includes a ramped front face 54, sloping at an angle of about 40° to the horizontal, and a rear face 56 which lies in an approximately vertical plane (see Figs. 2 and 3).

The catch member 52 is provided with protrusions 58 extending from the sides of the catch member 52. The protrusions 58 pass through openings 60 in the sheet metal mounting plates 14. A protrusion 58 bears on the upper face 30 of the central portion 28 of each arm. Downwards movement of the catch member 52 thus causes the protrusions 58 to bear downwardly on the faces 30 thus pivoting the arms 12 in an anti-clockwise direction as viewed in Fig. 1.

An actuation arrangement is provided for initiating downwards movement of the catch member 52. The catch member 52 is moved downwardly by an actuating lever 62 operated by tension in a cable 64. The cable 64 extends from the actuating lever to a handle provided on an upper part of the powered vehicle. Referring to Fig. 5, near the handle the cable 64 is attached to a cam 66 in the form of an eccentric circle which the cable 64 may wrap around. Initial movement of the handle causes the cable 64 to wrap around a relatively small radius portion 68 of the cam, whilst further movement of the handle causes the cable 64 to wrap around a relatively larger radius portion 70 of the eccentric cam 66. This arrangement helps overcome the conflicting requirements for maintaining a reasonable operating force at the handle, whilst giving sufficient travel to the actuating lever. It gives good leverage initially, as the handle is first moved, whilst giving greater travel to the cable once the initial spring force has been overcome. This provides an approximately constant operating force at the handle.

The connecting apparatus as described may be used to connect a powered vehicle either to a dolly or to a roll cage. The arms 12 are used for connecting the apparatus to a dolly, whilst the catch member 52 is used for connecting the apparatus to a roll cage. To make the apparatus easy for an operator to use, a single actuating lever may be used to disconnect the apparatus from a dolly and from a roll cage. The operation of the apparatus is described in more detail below.

In order to connect the apparatus to a dolly, the powered vehicle is moved towards a dolly until the nose 20 of each arm contacts an outer part of a recess 72 in the dolly 74 (see Fig. 2). The nose 20 is pushed into the recess until the ramped portion 22 contacts an inwardly sloping face 76 of the recess 72.

Further movement of the nose 20 and ramped portion 22 into the recess 72 causes the arm 12 to rotate against the bias of the spring 40. The arm 12 eventually rotates into a position in which it may pass under a lower extremity 78 of the inwardly sloping face 76. Once the ramped portion 22 of the arm 12 has passed this lower extremity 78, the bias of the spring 40 causes the arm 12 to rotate in the clockwise direction into the position shown in Fig. 2. In this position, the rear face 24 of the ramped portion 22 contacts a substantially vertical face 80 provided within the recess 72 in the dolly 74.

Because the arm 12 is biased in the clockwise direction by the spring 40, it is retained in place in the recess 72. The slight slope of the face 24 allows the arm to pivot somewhat relative to the recess 72. The arm is thus retained in the recess and the powered vehicle may be used to convey the dolly, with the relative pivotal movement of the two faces 24 and 80 allowing the dolly to be conveyed over uneven ground.

To release the connecting apparatus 10 from the dolly, it is necessary to pivot the arms 12 in an anti-clockwise direction before moving the powered vehicle backwards away from the dolly to remove the arms 12 from the recess 72. This is done by operating the actuating mechanism by use of a handle provided on the powered vehicle. Operation of the handle causes tension in the cable 64 which causes the actuating lever 62 to move the catch member 52 downwards. This causes the protrusions 58 to bear downwardly on the faces 30 on the arms 12. This forces the arms 12 to pivot in the anti-clockwise direction, allowing the arms to be disengaged from the dolly 74.

The connection apparatus may be used to allow the powered vehicle to engage a roll cage as follows. The powered vehicle is driven towards a roll cage until the ramped front 54 of the catch member 52 contacts a substantially horizontal bar of the roll cage. Continued forward movement of the powered vehicle causes the catch member 52 to move downwards, allowing the catch member 52 to pass under the substantially horizontal bar. This brings the horizontal bar into place in a recess 82 (see Fig. 2) defined by the rear face 56 of the catch member 52 and upwardly and forwardly directed faces 84 and 86 of the sheet metal mounting plates 14. In this position, some of the weight of the roll cage is borne by the upwardly directed faces 84 of the mounting plates 14.

In this position, the powered vehicle may be used to convey the roll cage.

To disengage the powered vehicle from the roll cage, the actuating mechanism is operated as previously described, to bring the catch member 52 downwards and to allow the connecting apparatus to disengage from the horizontal member of the roll cage.

There is thus provided a connecting apparatus which may be used to connect a powered vehicle either to a roll cage or to a dolly. A single actuating mechanism may be used to disconnect the apparatus from a dolly and from a roll cage.

Various modifications may be made to the above described embodiment without departing from the scope of the invention.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.