A lifting device of this type is known, for example, from GB-A-2 352 216. Fig. 3 of this document shows a lifting device which can be coupled to the towing hook of a car. For this purpose, the device comprises coupling means having a guide structure which is fixedly connected thereto. A lifting member can be moved up and down along the guide structure. The lifting member is provided with upwardly and downwardly directed hooks, to which, for example, a container provided with wheels can be attached. As a result of a lever arm then being actuated, the lifting member, together with the container which has been attached to it, can be moved upwards along the guide structure. Fig. 9 of this British Patent Application shows a lifting platform which can also be attached to the hooks of the lifting member. In this way, cargo for which there is not immediately space in the vehicle can be fixed to the lifting platform and carried along at the back of the vehicle on the towing hook.

A drawback of this known lifting device is that it prevents the tailgate or hatch (es) of the car from being opened. In many cases, it will only be possible to open the tailgate if the lifting device is completely removed from the towing hook. Moreover, the lifting device is unsuitable for transferring load from a raised lifting platform to a loading space of the vehicle, for example by means of a pushing movement.

It is an object of the present invention to at least partially overcome the abovementioned drawbacks and/or to provide a useable alternative, and in particular to provide a device for lifting and then transferring cargo into a loading space of a vehicle.

According to the present invention, this object is achieved by a lifting device according to claim 1. In this device, the lifting structure comprises a first part, which is fixedly connected to coupling means, and a second part, which is moveably connected to the first part. Furthermore, the second part is connected to a lifting platform. The second part can move with respect to the first part into a position in which the second part is located outside the area in which a vehicle flap moves when it is being opened or closed in the coupled position of the lifting device. This enables the lifting device to be coupled flexibly and advantageously to a towing member of a vehicle. The lifting platform can be moved up and down by actuation of drive means with the aid of the lifting structure, after which cargo can easily be transferred from the lifting platform to the vehicle loading space and vice versa. According to the invention, this is advantageously possible without the cargo having to be lifted over parts of the lifting device. Even during loading, the flap can be provided with the free space which it needs to be opened or closed.

Within the context of the present invention, the term flap is to be understood as meaning both a vehicle door or vehicle flap which can move about a horizontal axis and a vehicle door or vehicle flap which can move about a vertical axis.

In particular, in the coupled position, the first part extends substantially below the underside of the flap, while for the second part there is at least one bottom loading position, in which it likewise extends substantially below the underside of the flap.

More particularly, there is also a transporting position, in which the second part extends at least partially above the said underside of the flap. This enables the lifting structure to be moved into the transporting position after a loading operation. The entire lifting structure can then be moved to a sufficient height above the ground, so that it is not in the way of vehicle manoeuvres, in particular if this involved passing over speed ramps and the like.

In one embodiment, the second part of the lifting structure comprises a guide structure which is connected to the first part in such a manner that it can move up and down and along which the lifting platform can be moved up and down. Where the guide structure, in the loading position, extends substantially beneath the underside of the flap, it will now, in the transporting position, extend at least partially above the said underside of the flap. The moveable connection between the guide structure and the first part makes it easy to provide the loading position and the transporting position, while the lifting platform can overcome the lifting height required during loading, namely from the ground to the floor height of the loading space.

In another embodiment, the second part comprises at least one pair of lifting arms which are rotatably connected to one another.

The pair of lifting arms in this case is on one side pivotably connected to the first part and on the other side pivotably connected to the lifting platform. The lifting arms can advantageously extend below the underside of the flap throughout the entire loading process. In the transporting position, the lifting arms can easily be rotated until they are above the abovementioned underside of the flap. The rotatable connection between the lifting arms and the first part makes it possible, in a simple way, to provide the loading position and the transporting position, while in this case too the lifting platform can cover the lifting height required during loading, i. e. from the ground to the floor height of the loading space.

Further preferred embodiments are defined in the subclaims.

The invention also relates to an assembly of the lifting device with a vehicle according to claim 16 and to the use of the lifting device according to claim 17.

The invention will be explained in more detail with reference to the appended drawing, in which: fig. 1 shows a perspective view of an embodiment of the lifting device according to the invention with a guide structure which is in the loading position; fig. 2 shows a view corresponding to that shown in Fig. 1, with the lifting platform in the top position; fig. 3 shows a view corresponding to that shown in Fig. 1, with the guide structure in the transporting position ; fig. 4 shows a diagrammatic side view of Fig. 1; fig. 5 shows a diagrammatic side view of Fig. 2; fig. 6 shows a diagrammatic side view of Fig. 3; fig. 7 shows a rear view of Fig. 5; fig. 8 shows a plan view of Fig. 5; fig. 9 shows a perspective view of a design variant with a lifting structure in the loading position; fig. 10 shows a view corresponding to that shown in Fig. 9, with the lifting platform in the top position; fig. 11 shows a view corresponding to that shown in Fig. 9, with the lifting structure in the transporting position ; and fig. 12 shows a diagrammatic cross-sectional view through a transmission mechanism which is accommodated in the lifting arms shown in Fig. 9-11.

The lifting device shown in Fig. 1-8 is denoted overall by reference numeral 1 and comprises a lifting structure 2, which, by means of a first part 2a, is connected to coupling means 3. The coupling means 3 are in this case releasably connected to a towing hook 4 of a vehicle 5. Coupling means of this type are known from the prior art, for example for cycle carriers. The lifting structure 2 also comprises a second part 2b which comprises a guide structure 7. The guide structure 7 in turn comprises two profiled guides 8 which are located on either side and extend vertically. Furthermore, there is a lifting platform 10, which can be moved up and down in the vertical direction along the guide structure 7. Between the guide structure 7 and the lifting platform 10 there is a roller guide, which in this case is formed by two running wheels 11, 12 which are located one above the other and are guided in rear parts of the profiled guides 8.

According to the invention, there is a moveable connection between the first part 2a, which is fixedly connected to the coupling means 3, and the guide structure 7. The moveable connection is in this case formed by a roller guide with two pairs of guide wheels 13, 14 located one above the other, which are guided in front parts of the profiled guides 8.

The connection, which can move up and down, between the coupling means 3 and the guide structure 7 advantageously enables the guide structure 7 to be moved into at least two positions during use, namely a loading position (Fig. 1,2, 4,5) and a transporting position (Fig. 3,6).

In the loading position shown in Fig. 1 and 4, the guide structure 7 is in the lowest position with respect to the coupling means 3. As can clearly be seen, the guide structure 7 in this case extends substantially between the ground 15 and the top side of the coupling means 3. The guide structure 7 in this case also extends substantially below the bottom level of a tailgate 17 of the vehicle 5. In the position shown in Fig. 1 and 4, the flap 17 can be opened and closed as desired, as diagrammatically indicated by dashed lines, without colliding with part of the lifting device 1 and without the lifting device 1 having to be removed from the towing hook 4 for this movement to take place.

The lifting platform 10 in Fig. 1 and 4 is in its bottom position with respect to the guide structure 7. In this position, the loading platform 10 can simply be loaded from the ground 15.

Then, the lifting platform 10 can be moved upwards along the guide structure 7 by means of a winch device 20, which is diagrammatically indicated in Fig. 8. For this purpose, the winch device 20 is connected, by means of cables 20 guided over cable pulleys 21,22, to a bottom connecting bar of the lifting platform 10. The cables 23 are wound up as a result of the winch device 20 being actuated, which can be carried out either by hand or electrically via the electrics system of the vehicle, and as a result the lifting platform 10 will move upwards. At a given moment, the top guide wheels 11 of the lifting platform 10 will come into contact with stops which are provided in the top of the associated profiled guides 8. In the loading position, the guide structure 7 can move freely up and down along the guide wheels 13,14 connected to the first part 2a. As a result, the lifting platform 10, as the cables 23 are wound up further, will to some extent move the guide structure 7 up with it with respect to the coupling means 3. This free mobility advantageously enables the lifting platform 10 to be moved to a height which is such that it comes to lie substantially in line with a base surface 24 of a loading space of the vehicle 5.

As a result, it is advantageously possible to push cargo off the loading platform 10 into the loading space of the vehicle 5. The highest position of the lifting platform described 10 above, in which the guide structure 7 is also moved upwards to some extent, is shown in Fig. 2 and 5.

Fig. 2 and 5 also clearly show that the lifting device 1 is provided with a support element 25. The support element 25 is connected to the first part 2a in such a manner that it can be lowered. In the loading position, the support element 25 is moved downwards until it is supported against the ground 15, after which the support element 25 is locked in this position with the aid of bolts 26. In this way, the load on the connection between the first part 2a of the lifting structure 2 or the coupling means 3 and the carrying member 4 is relieved, for example when the lifting platform 10 is being used to lift heavy loads.

After the loading or unloading operation has been completed, the lifting device 1 according to the invention can easily be returned to the form of a compact unit which scarcely projects downwards or does not do so at all, and is certainly not in the way when the vehicle is dealing with traffic obstacles, such as speed ramps. The moveable connection between the guide structure 7 and the first part 2a advantageously makes it possible for the guide structure 7, together with the lifting platform 10, to be moved into a transporting position as shown in Fig. 3 and 6. In the position shown, the bottom guide wheels 14 of the first part 2a are in contact with stops which are provided in the bottom of the associated profiled guides 8.

In the transporting position, the support element 25 is also moved upwards. In this case, the connection between the support element 25 and the first part 2a is advantageously designed in such a manner that the support element 25 can also be rotated about a substantially vertical axis. As a result of the support element 25 also being rotated while it is being moved upwards, it is possible for the guide structure 7 which has been moved upwards to be locked in this position. The guide structure 7 as it were comes to rest on the top side of a horizontal bar of the support element 25. In addition and/or as a variant, it is also possible to provide a separate locking member.

The lifting platform 10 is connected to the guide structure 7 in such a manner that it can be folded up. As a result, the lifting device 1 does not project significantly far back in the transporting position. The foldability is advantageously achieved through the fact that the bottom guide wheels 12 of the lifting platform 10 can easily be disengaged from the profiled guides 8 via cutouts provided in the associated profiled guides 8. The lifting platform 10 can then easily be pivoted about the top guide wheels 11 into the folded-up position. Since the lifting platform 10 itself is also designed such that it can be folded up, it is possible to achieve an even more compact position. To lock the lifting platform 10 in this position, it is possible to provide a locking member which, by way of example, engages between the guide structure 7 and the lifting platform 10.

Fig. 9-11 show a variant of the lifting device, in which the lifting structure once again comprises a first part 102a and a second part 102b. The first part 102a is fixedly connected to coupling means 103, while the second part 102b comprises two pairs of lifting arms 104, 105 which are located on either side. The lifting arms 104 and 105 are rotatably connected to one another. In this arrangement, the free end of the lifting arm 104 is pivotably connected to the first part 102a. The free end of the lifting arm 105 is pivotably connected to a lifting platform 107. Furthermore, two support elements 110, which are rotatably connected to the first part 102a and are intended to be supported on the ground in the loading position, extend on either side.

Inside the lifting arms 104,105 there is a transmission mechanism which is connected to drive means and with the aid of which the lifting arms 104,105 can be rotated with respect to one another, with respect to the first part 102a and with respect to the lifting platform 107. A rotation in this case results in an upward or downward movement of the lifting platform 107. As a result of two interacting lifting arms being used, it is advantageously possible to enable the lifting platform to be moved up and down.

In the design variant shown, the lifting arms 104, 105 are designed to be of different lengths, and the transmission mechanism is designed in such a manner that a rotation of the lifting arm 104 about the first part 102a leads to a greater rotation of the lifting arm 105 with respect to the lifting arm 104. Furthermore, there is a compensation transmission which ensures that the lifting platform 107 remains substantially horizontally oriented during rotation of the lifting arms 104,105.

Fig. 11 shows the transporting position for the lifting device.

This can easily be reached by rotating the lifting arms 104,105 further until the lifting platform 107 comes to lie close to the rear side of the vehicle. It is also possible for the support elements 110 to be rotated upwards until they are close to the vehicle.

Fig. 12 shows an embodiment of the transmission mechanism. A gearwheel 115, about which a gearwheel 116 accommodated in the lever arm 104 can run, is mounted fixedly on the first part 102a. The axle on which the gearwheel 116 is fixedly mounted is also provided with a gearwheel 117 mounted fixedly thereon. Via a chain, the gearwheel 117 transmits a rotation to a gearwheel 118, which is mounted in such a manner that it can rotate freely on a second axle accommodated in the lifting arm 104. The gearwheel 118 is in turn fixedly connected to the lever arm 105. Therefore, a rotation of the lifting arm 104 about the first part 102a leads to a rotation of the lifting arm 105 with respect to the lifting arm 104. The relative rotation can in this case be influenced by a suitable choice of gear transmission ratios. The lifting arm 104 can be rotated with respect to the first part 102a by suitable actuation of a hydraulic cylinder 119.

The transmission mechanism is coupled to a compensation transmission. Furthermore, a gearwheel 125 is mounted fixedly on the first part 102a. Via a chain, this gearwheel 125 acts on a gearwheel 126 which is fixedly mounted on the axle in the lifting arm 104 about which the gearwheel 118 can rotate freely. This axle is also the pivot axle about which the lifting arm 105 can rotate with respect to the lifting arm 104 and extends into the lifting arm 105.

There, a gearwheel 127 is fixedly mounted on the axle. Via a chain, this gearwheel 127 transmits its rotation to a gearwheel 128 which is fixedly connected to a pivot axle which forms part of the lifting platform 107. Therefore, a rotation of the lifting arm 104 about the first part 102a simultaneously leads to a rotation of the lifting arm 105 with respect to the lifting arm 104 and to a compensatory opposite rotation of the lifting platform 107 with respect to the lifting arm 105, with the result that the lifting platform 107 remains substantially horizontally oriented. The compensation can in this case be influenced by a suitable choice of gear transmission ratios.

In addition to the embodiments shown, numerous variants are possible. For example, the lifting structure can be designed with a guide structure which can be held in a fixed, lowered loading position throughout the entire loading process. In order then also to achieve the effect whereby the lifting platform can be moved into a top position, in which it substantially adjoins the base surface of the vehicle loading space, the moveable connection between the lifting platform and the guide structure has to lie substantially below the top side of the lifting platform.

In another variant, just one, preferably centrally located, profiled guide or pair of lifting arms is used instead of profiled guides or pairs of lifting arms arranged on either side. If the lifting platform is only intended to lift light loads, it is possible to consider the possibility of omitting the support element. In addition to cable-winch systems or a hydraulic cylinder, other drive means are also possible, such as gear-rack transmissions. The drive means can be actuated manually but may also be provided with an electric drive which is connected to the vehicle electrics system. In addition to coupling means which are suitable for mounting on a vehicle towing hook, it is also possible to use coupling means which are suitable for attachment to a mounting flange on a vehicle, such as a delivery van.

Therefore, the invention creates a multifunctional lifting device which is suitable in practice for loading the loading space of a vehicle, while the loading-space flap can be opened and closed before and/or during the loading operation. In the transporting position, the lifting device can advantageously be restored to a compact unit. The device is of simple design and can in principle be made suitable for any type of vehicle by means of a suitable selection of coupling means.