AU3778000A - Loading trolley and its loading vehicle - Google Patents

Description

S&F Ref: 509684

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

I

Name and Address of Applicant Actual Inventor(s): Address for Service: Invention Title: Armtop ZAC des Pedras 44117Saint-Andre-des-Eaux France Alfred Hubschen Spruson Ferguson St Martins Tower 31 Market Street Sydney NSW 2000 Loading Trolley and its Loading Vehicle The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845c Loading Trolley and its Loading Vehicle The present invention relates to a loading trolley capable of being stowed, together with its load, on an elevated loading tray of a transport vehicle, as well as a loading vehicle for such a trolley.

It relates, more in particular, to a loading trolley capable of [so] being stowed, consisting of a load-carrying tray fitted with a set of wheels for the movement of the tray on the elevated loading tray and a set of wheel-carrier legs in front and at the rear, respectively, capable of being adjusted in height and pivotally linked to the load-carrying tray so as to take up one position for bearing on the ground and a folded position, each pair of wheel-carrier legs, front and rear, respectively, being equipped with an unlockable device for locking the legs at least in their deployed position.

A loading trolley of this type is especially described in the application for the European patent S, EP-A-0.439.812. Such loading trolleys are used in particular by transport vehicles in which loads must frequently be loaded or unloaded from the vehicle, with these loading and/or unloading operations having to be carried out by a single person. Such loading trolleys are intended to ease the loading and °unloading operations and in particular lessen the physical fatigue of the operators.

15 However, such loading and unloading operations must be capable of being carried out with all safety. This is not the case with the loading trolley described in the above-mentioned European patent application. In fact, this loading trolley does not ensure with any certainty that the front legs will indeed fold back, due on the one hand to the positioning of the unlocking device of the locking system for the front feet in their deployed position, and, on the other hand, due to the absence of a supplementary 20 safety device.

*o o This problem is not solved either by the loading trolley described in the German patent application DE-A-3.007.578.

:The same is true of the loading trolley described in patent DE-195 14 912. In that trolley, the device for adjusting the height of the wheels is made up from a system with a spring-loaded button, so that the height or length of the legs is determined at the moment of the deployment of the legs. Once this height is adjusted, it can no longer be modified, particularly when the load-carrying tray is under load. As a result, it is impossible to adapt to vehicles having an elevated loading surface with a different ground clearance. Because of this, one cannot consider unloading a vehicle with a view to loading another vehicle having a different ground clearance. Furthermore, once again, no system prevents the untimely recoil of the trolley when the latter is partially introduced into the vehicle, with the front legs being in the folded position. The same comments can be made regarding the loading trolley described in patent DE-2.635.238.

It is a first objective of the present invention to propose a loading trolley the design of which allows the automatic unlocking of the front legs, from the deployed position to the folded position, in such a way as to prevent a trolley from exiting after having been at least partially introduced into the vehicle when said front legs are in the folded position.

Another aim of the present invention is to propose a loadtrolley the design of which prevents any egress of the trolley from the vehicle when any leg of the trolley is in the folded position.

It is another objective of the present invention to propose a loading trolley the design of which limits the risks of the front legs of the trolley folding while the tray of the trolley is unsupported.

C08285 Another objective of the invention is to propose a loading trolley the design of which allows it to adapt to vehicles having any ground clearance whatsoever of their elevated loading tray so that the trolley can be unloaded from one vehicle with a view of loading it onto a vehicle having a different ground clearance.

Another objective of the invention is to propose a loading vehicle for such a loading trolley the design of which affords some protection to the vehicle, especially of the bumper bar of the latter during manoeuvring of the loading trolley.

To this end, the object of the invention is a loading trolley capable of being loaded, together with its load, onto the elevated loading surface of a transport vehicle, this trolley being made up of a load tray equipped with a set of rolling or sliding devices which serve to move the tray on the elevated loading surface and of a set of wheel-carrier legs at the front and at the rear, respectively, which are adjustable in height and are pivotally linked to the loading trolley so as to take up a supporting position on the ground and a folded position, the front and rear wheel-carrier legs each being equipped with an o unlockable device for blocking the legs at least in the deployed position, characterised in that the kinematically integral [jointly moving] pair of front legs and the kinematically integral pair of rear legs are each equipped with a separate height-adjusting device moved during use to increase or decrease the length of the legs, whether the tray is loaded or empty, by means of a control device actuated by an operator so as to achieve independent adjustment of each pair of legs of the loading trolley, said load-carrying tray being equipped with a first stop close to its front edge for engaging with a stop disposed on the loading surface of the vehicle and thus prevent the untimely recoil of the load-carrying tray when its front legs are folded, with the engagement or disengagement of said stops being obtained by means of adjusting the height of at least one pair of legs.

Thanks to the design of the height-adjustment device of each pair of legs and to the presence of stops, the automatic folding of the front legs of the loading trolley can take place in all safety, without the possibility of a recoil of the trolley partially introduced into the vehicle, since the disengagement of the stops cannot occur before the front legs are locked in the unfolded position [and] bearing on the ground.

The invention furthermore has the object of a goods vehicle of the type having an elevated loading surface, this vehicle being fitted for loading a loading trolley of the above-mentioned type.

The invention can be well understood by reading the following description of examples of embodiment, with reference to the annexed drawings wherein: Fig. 1 shows a perspective view, from below, of a loading trolley according to the invention, said trolley being placed along the section of the tray; Fig. 2 shows a perspective view from above of a loading trolley according to the invention as well as the set of elements necessary to fit the vehicle for receiving such a loading trolley; Fig. 3 shows a partial perspective view of the operation of the control device for unlocking the front legs of the loading trolley, and Figs. 4A to 4D show, schematically and partially, different stages of loading a loading trolley according to the invention into a vehicle.

C08285 The loading trolley that is the object of the invention is represented in the drawings under the general reference 1. This loading trolley is made up of, in an otherwise well-known manner, of a load tray 2 consisting of a flat surface fitted with a certain number of crossbars and beams to make said flat surface rigid. This tray 2 is itself equipped with a set of wheels shown under 3A and 3B in the drawings. These wheels serve to move the tray 2 on an elevated receiving surface 17, formed for example by the load platform of a goods vehicle. This load tray 2 is also equipped with a set of wheelcarrier legs each at the front and rear, capable of being adjusted in height. The front wheel-carrier legs are shown in 4A. These front wheel-carrier legs are the legs that are to be placed first on the elevated reception surface 17 during the loading of the loading trolley with its load onto said elevated reception surface 17.

The front legs 4A can be adjusted in height so as to increase or decrease their length by means **of an appropriate element such as a device of the type nut/worm screw, also called mechanical jack.

The length-adjustment device fitted to one front leg is mechanically coupled to the other front leg so as the make the front legs kinematically integral, that is to say, they can be driven simultaneously 15 toward increasing or decreasing their length. Actuation of these mechanical jacks, in particular turning the worm screws, can be achieved by means of a crank 15 situated at the rear edge of the trolley and manipulated by an operator.

The rear legs 4B are fitted with a similar height-adjustment device.

Accordingly, the front legs 4A and rear legs 4B can be adjusted in height separately by means 20 of mechanical jacks 14A, 14B in order to obtain an individual adjustment of each pair of legs. These mechanical jacks are shown more particularly in Fig. 2. These mechanical jacks consist of a set of pinions and ring-and-pinion systems coupled to each pair of legs and operated by way of a crank or an electrical device, such as a motor, to drive their rotation.

o o" Two telescopic tubes for example constitute the front wheel-carrier legs 4A, moving by relative axial motion when the mechanical jack 14A is operated, engaging one of the said tubes. As Fig. 2 shows, operating the crank 15 [that is] linked to a pinion-carrying axle, shown as 14A" in Fig. 2, allows to drive, by rotation, the pinion carried by a stem 14A', said pinion engaging a pinion carried on a threaded stem 14A" that is co-axial with the leg and engaged with the threading or [with] a fixed nut of one of the telescopic tubes making up one of the elements of the front wheel-carrier legs. In this way, the rotation of the threaded stem causes an axial movement of the tube, which is fixed or limited as regards rotation around its longitudinal axis and which is in engagement with the aforementioned threaded stem. An analogous system is provided for the rear legs 4B. Quite obviously, equivalent elements such as an electrical actuator could have been envisaged. The advantage of using such a height-adjusting device lies in being able to set, by means of a simple mechanism, the height of the legs in the loaded or unloaded state of the load tray, and to obtain a particularly precise height adjustment for each pair of legs. It is to be noted that in the example shown, it is the stem 14A' which ensures the linkage between the mechanical jacks of each front leg 4A in such a way that the height adjustment of each leg takes place simultaneously.

As far as the front legs 4A are concerned, the telescopic tubes are formed in such a way that one possesses a guide slot, the other having a finger that moves inside the guide slot during the axial C08285 movement of said telescopic tubes in such a way that each front wheel mounted rigidly on one of the tubes transits from a position that is parallel to the longitudinal axis of the tray, as shown in Fig.

2, which position corresponds to the deployed position of the front legs 4A, to a position that is at a right angle to the longitudinal axis of the load tray 2 in the folded position of the legs, the position that corresponds to that shown in Figs. 4C and 4D. One sees that the crank shown as 15 in the drawings can equally operate the mechanical jacks 14B that drive the movement of the rear legs 4B of the vehicle or the mechanical jacks 14A that drive the movement of the front legs 4A of the vehicle. All that is needed to do that is to link the crank 15 to the corresponding mechanical jack. The crank 15 is therefore removably attached to the trolley. One could, however, have provided for a single crank linked to a tripping system to be able to act at will on the mechanical jacks with which the front and rear legs are fitted. Each set of front and rear wheel-carrier legs, respectively, is furthermore pivotally oooo linked to the load tray 2. This pivotal movement is effected manually for the rear legs. Due to this pivotal linkage to the load tray 2, each set of legs can assume a position of bearing on the ground, and a folded position.

15 To ensure that each set of wheel-carrier legs is kept in the position of bearing on the ground each front pair 4A or rear pair 4B, respectively, of the wheel-carrier legs is equipped with a unlockable device 5, 6 or respectively 6, 13 for locking the legs in place. A partial representation of this locking element is shown in Fig. 3. The locking element for the front legs 4A consists of an unlockable hook that fixes a strut 6, linked at its other end to the mount of the front wheel-carrier legs 4A, to the load tray 2. The unlocking of the hook 5 lets the strut move in a sliding movement, thus allowing a pivoting motion by the front legs 4A. The locking element for the rear legs 4B is formed analogously by a strut 6 extending between tray 2 and the mount of the rear legs 4B, as well as a manually unlockable hook shown under 13 in Fig.2.

The wheels fitted to the set of rear wheel-carrier legs 4B are swivelling wheels whereas the wheels fitted to the set of front wheel-carrier legs 4A are non-swivelling.

Each mobile front leg 4A can be unlocked from the position of bearing on the ground to a folding position by means of a control element 7, 8 operated by the load tray 2 bearing on the receiving surface 17 of the vehicle. In the examples shown, the control device for unlocking the locking element of the front legs in their deployed position consists of a movement element, such as a wheel 7, mobile within a clevis, designated 8 in the drawings, [and] pivotally attached under the said load tray 2. This clevis 8 is linked to the locking element 5,6 of the front legs 4A by means of a linking element 9 such as a connecting rod so that the pivotal movement of the clevis 8 causes a simultaneous movement of the locking element 5 of the locking device 5, 6 of the front legs 4A, thus causing the unlocking of the front legs 4A. Thus, in the example shown in Fig. 3, the force F applied to the wheel 7 and the clevis 8 when the load tray 2 comes to bear on the receiving surface 17 of the vehicle, causes the rotation of the clevis 8 around the axis X in the direction of the arrow shown in Fig.

3. This rotation of the clevis 8 causes a movement of the connecting rod 9 in the direction of the arrow. This in turn then causes the locking element 5 of the locking device 5,6 of the front legs 4A to rotate around the axis X in the direction of the arrow shown in Fig. 3. With this design of the control C08285 element one achieves the automatic unlocking of the locking device 5,6, thus permitting a subsequent pivoting movement of the front legs 4A.

However, in order to ensure the total safety required during this unlocking process, the tray 2 is equipped with a first stop 10 shown in Fig. 1. This stop 10 is close to the front edge of the load tray 2 so as to cooperate with a stop 12 arranged on the receiving surface 17 of the vehicle and thus to prevent the untimely recoil of the load tray 2 when its front legs are in the folded position. In fact, due to the relative positioning of the stop 10, the stop 12 and the control element 7,8, unlocking of the front legs 4A [to change] from a position of bearing on the ground to a folded position cannot be effected on said surface 17 unless the stop 10 has moved beyond the stop 12. As a result the stop 10, situated between the control element 7,8 and the front edge of the tray 2, is placed sufficiently far from the control element 7,8 to be able to cooperate with the aforementioned stop 12. Besides, and in a manner obvious to the person skilled in the art, the control element 7,8 in its locked position, projects above the plane defined by the wheels 3A, 3B of the tray 2 that let the latter move on the surface 17.

By contrast, the control element 7,8 and the stop 10 are sensibly in the same plane.

is To complete the example, the load tray 2 is equipped with a second stop 11 close to its rear edge, again shown in Fig. 1. This stop 11 cooperates with the stop 12 arranged on the receiving platform of the vehicle to ensure that the load tray 2 is immobilised in the transport position. As regards the rear legs 4B, these may be folded by lifting, with manual unlocking of the device locking [them] in the ground-supported position. The front legs, on the other hand, take up a folded position under the tray 2 parallel to the said load tray 2. This folded position of the front wheel-carrier legs is shown in Fig. 4D.

In practice, such a roll-on load trolley functions as follows. It is appropriate first of all to put in place all of the necessary fittings on the receiving surface 17 of the transport vehicle. To this end, the stops 12 are preferably carried by two rails 18 capable of being adapted to be attached to the elevated receiving surface 17 of the goods vehicle. One can also provide a bumper protection bar 16 at the rear of the platform or receiving surface 17, said bar 16 being retractable. Once this equipment has been permanently put in position, the loading trolley 1 can then be loaded into the vehicle. To achieve this, and as Fig. 4A shows, the trolley is brought to a position at least partially above the elevated receiving surface 17 of the vehicle as shown in Fig. 4B, with the legs 4A abutting against the rear of the vehicle. To achieve this, a height-adjustment has been made to the front legs 4A to allow the tray 2 fitted with the stop 10 to pass over the stop 12 fitted to the surface 17 of the vehicle, said stop 12 being placed in the path of the stop 10. Once this at least partial introduction of the tray 2 has been achieved, the load tray 2 is once more lowered by the height adjustment of the front set of wheelcarrier legs 4A. During the course of this lowering of the tray 2, the control element 7,8 is activated by the load tray 2 bearing upon the receiving surface 17 of the vehicle. The activation of this control element 7,8 causes the blocking device for the front wheel-carrier legs to be unlocked. Continued introduction of the load trolley 2 into the interior of the vehicle causes by the front wheel-carrier legs 4A bearing upon the vehicle protection bar 16 these [legs] to pivot until they reach a folded position in which the front legs 4A are placed under the tray of the trolley approximately parallel to the latter.

One then continues pushing the trolley forward until the set of rear legs 4B touch the bumper C08285 protection bar 16 of the vehicle. In this position the second stop 11 near the rear of the tray has also passed the stop 12 fitted to the elevated reception surface of the vehicle. The locking element of the device blocking the rear legs 4B is then operated manually after [any] height adjustment, if required, of the rear legs 4B. The legs are made to rotate by 180 degrees to end up taking up a position as per Fig. 4D. The trolley can then again be pushed further into the interior of the vehicle so as to be completely placed there once more. The retractable bumper protection bar 16 is equally moved pivotally to become stowed inside the vehicle. It allows preventing any movement by the trolley during transport.

One finds that, regarding the functioning such as described above, the trolley is perfectly 10 immobilised inside the vehicle due to the presence of the stops 10, 11, 12. In fact, in this position of oooo bearing upon the receiving surface 17, the stops 10, 11 are positioned in the path of the stop 12 so that any untimely recoil of the load tray 2 is impossible with the legs in the folded position. Quite °o obviously, for the egress of the trolley one proceeds in the same way, deploying first the rear legs 4B, while ensuring the height adjustment in the direction of an extension of the latter by operating the 15 mechanical jack 14B to allow the stop 11 to pass over the stop 12 and to ensure a progressive egress of the trolley until the trolley comes to but against the stop 12 with its stop 10. In this position, the rear legs being raised [and] in the extended position, the trolley is inclined toward the front legs 4A. The front legs 4A deploy under their own weight and lock automatically in the ground-supported position.

They are then adjusted in height to free the stop 10 from its engagement with the stop 12. The trolley can now be completely withdrawn from the vehicle. The engagement and the disengagement of the stops 10, 12 in this case are carried out solely by the height adjustment of the front legs.

In conclusion, the stowing and unloading of such a trolley are particularly easy.

o C08285

Claims (11)

1. Loading trolley capable of being stowed, with its load, on an elevated receiving surface of a transport vehicle, said trolley consisting of a load tray fitted with a set of rolling or sliding elements serving the movement of the tray on the elevated receiving surface and of a set of, respectively, front and rear wheel-carrier legs, adapted to being adjusted in height and pivotally linked to the load tray so as to assume a ground-supported position and a folded position, the front and rear wheel-carrier legs respectively each being equipped with an unlockable device for locking the legs at least in the deployed position, characterised in that the kinematically integral front pair of legs and the kinematically integral rear pair of legs are each equipped with a height-adjustment device moved to operate in the direction of an increase or a decrease of the length of the legs, in the loaded or unloaded state of the tray, by a control element operated by an operator to obtain an independent adjustment of each pair of legs of the load tray, said load tray being equipped with a first stop near its ***frontal edge for engaging with a stop disposed on the reception surface of the vehicle and thus prevent the untimely recoil of the load tray when the front legs are in the folded position, the 15 engagement or disengagement, respectively, of said stops being achieved by adjustment of the height of at least one pair of legs.

02. Loading trolley capable of being stowed according to claim 1, characterised in that the load tray is equipped with a second stop near its rear edge, this stop engaging with the stop disposed on the reception surface of the vehicle to ensure the immobilisation of the load tray in the transport 20 position.

3. Loading trolley capable of being stowed according to claim 1 or claim 2, characterised in that the rear legs can be folded by raising while manually unlocking the device that is locking them in the ground-supported position.

4. Loading trolley capable of being stowed according to any one of claims 1 to 3, characterised in that the front legs take up, in the folded position, a position under the load tray parallel to said load tray.

Loading trolley capable of being stowed according to any one of claims 1 to 4, characterised in that the front and rear pairs of legs can be adjusted in height in the loaded or unloaded state of the tray by means of separate mechanical jacks to achieve an independent adjustment of each pair of legs.

6. Loading trolley capable of being stowed according to claim 5, characterised in that the front wheel-carrier legs are made up of two telescopic tubes given a relative axial movement when the operation of the mechanical jack engages one of the said tubes, one of these tubes having a guide opening for a pin carried on the other tube so that each front wheel, mounted fixedly to one of the tubes, passes from a position that is parallel to the longitudinal axis of the load tray when the front legs are deployed to a position at a right angle to the longitudinal axis of the load tray when the front legs are in the folded position.

7. Loading trolley capable of being stowed according to any one of claims 1 to 6, characterised in that the mobile front legs can be unlocked from the ground-supported position to a C08285 r 8 folded position by a control element activated by the load tray bearing upon the reception surface of the vehicle.

8. Loading trolley capable of being stowed according to claim 7, characterised in that the control element of the device for locking the front legs in the deployed position is constituted by an element of movement such as a wheel, mobile within a clevis mounted pivotally under said load tray, said clevis being linked by way of an linkage element such as a strut to the device for locking the front legs so that the pivoting movement of the clevis causes a simultaneous movement of the locking element of the device for locking the front legs, causing the unlocking of the front legs.

9. Goods transport vehicle of the kind having an elevated loading surface, characterised in that it is adapted for stowing a loading trolley according to any one of claims 1 to 8.

10. Goods vehicle according to claim 9, characterised in that a retractable bumper protection bar is provided at the rear of the reception surface of the vehicle.

11. A loading trolley substantially as hereinbefore described with reference to the .accompanying drawings. Dated 29 May 2000 ARMTOP t. too# Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON C08285