Loading lift device mountable to a vehicle

Abstract: Loading lift device (1) comprising two columns (3) connectable to the container (12) of a vehicle when in vertical position, with sliders (4) being mounted in or around said columns, said sliders (4) being adjustable in height by the fact that each slider (4) is connected to a hoisting cylinder (7). The hoisting cylinder (7) extends almost parallel to the columns (3) and is connected to it, or to a fixed part of the vehicle (2). Between the sliders (4) extends a loading platform (5) that can be pivoted around a pivot shaft (16) being square to the sliders (4) and which by means of closing cylinders (8), can be pivoted from the operational position, in which a load can be situated thereon, to an almost vertical position. The pressurized medium cylinder (7) is substantially outside the path of the slider (4) and is connected to a low point thereof, or to a point of the loading platform (5) being near it. The axes of a column (3) and of the accompanying hoisting cylinder (7) and closing cylinder (8) are in a plane (25) being almost square to the pivot shaft of the loading platform (5).

Description: The invention relates to a loading lift device mountable to a vehicle as this is described in the preamble of the main claim and is known from US-A-3 804 276. Concerning this publication it can be remarked that, as in particular appears from the figures 1 and 3 of it, the tubular part of a hydraulic cilinder is connected to the mast assembly connected to the truck body. Each mast assembly is provided with a guide in which a mast is movable in vertical direction. The open side of said guide faces the other mast guide across the rear opening of the truck body. The pivot points for the loading platform are connected to said masts such that said platform is situated between said masts when brought to the vertical position. If now said known device should be provided with at least one cylinder for operating the loading platform, said cylinder will have to be positioned inside of said masts and so will decrease the width of the free opening of the container of the vehicle. This causes difficulties when loading and unloading large objects. Now the object of the invention is to carry out the loading lift in such a way, that also when using a hydraulic cylinder for pivoting said loading platform the free opening of the container of the vehicle can be utilized optimally. According to the invention the features are used as these are indicated in the characterizing portion of the main claim. It is remarked that according to said claim the upper end of the cylinder is connected to the column or a fixed portion of the container and the lower end to the slider or a portion of the loading platform. By doing this the slider can be moved over a larger distance than in case of the device according to said US patent in which the lower end of the cylinder is fixedly connected to the container or the column. DE-A-3 412 983 describes the use of hydraulic cylinders for pivoting the loading platform. In this case the sliders to which said cylinders are connected are moved by cables running over various rollers to one hydraulic cylinder near the roof of the container. It will be clear, however, that cables are vulnerable and wear-sensitive parts. Further some guiding rollers and connecting means for the cables will be at such a location that the free opening of the container of the vehicle will be decreased. If instead of cables hydraulic cylinders are used these will decrease the width of the free opening of the container. With an arrangement of a hoisting cylinder in which it extends parallel to the accompanying column, one could employ a fixed connection of both ends of the hoisting cylinder with the slider and the column, respectively. However, in order to prevent the occurence of bending moments on a hoisting cylinder, or on the parts to which it is connected, it can be provided for, that each hoisting cylinder is pivotably connected to the slider and to the column or a fixed portion of the container. It is also possible that the part of the slider being outside the column is tubular, in which the hoisting cylinder connected to it is at least partially inside this tube and the pivot connected to the closing cylinder is fixed to the tubular part. The slider can also comprise a tubular portion being part of the hoisting cylinder. Then, the hoisting cylinder will substantially extend parallel to the column and the tubular portion can be provided with the pivot for the closing cylinder. One does need to take into account the fact that the closing cylinder will exert transverse forces on the hoisting cylinder, so that the latter must be dimensioned to be able to accomodate these forces. In general, the axes of the columns, of the hoisting cylinder and of the closing cylinder, will extend almost parallel to each other in the vertical position of the loading platform. The distance across which the parts will protrude beyond the container will then be as small as possible. By employing the weight of the various parts, both the hoisting cylinders and the closing cylinders can be single-acting pulling cylinders. They cost less than double-acting cylinders and moreover the number of channels for transport of pressurized medium can be limited. Here, the hoisting cylinder can be designed in such a way, that the portion of the piston rod protruding outside the cylinder is directed upwards and that the piston rod is provided with a bore through which pressurized medium can be supplied to the space above the piston. When the hoisting cylinder extends almost parallel to the column, then the connection of the pressurized medium channel to the piston rod will substantially always remain in a fixed position, since it need not follow the movement of the loading lift device. The invention is further explained by means of an embodiment, shown in the drawing, in which: Fig. 1 diagrammatically shows a side view of a loading lift device according to the present invention, in its non-operative position; Fig. 2 diagrammatically shows a plan view of the loading lift device of Fig. 1; and Fig. 3 shows a view corresponding to Fig. 1, but with the loading platform in the operational position. The loading lift device according to the invention can be mounted to the vehicle 2 and comprises the vertical columns 3, along which sliders 4 are movable. The loading platform 5 is pivotably connected to the sliders 4 by means of the pivot shaft 16. The pivot shaft 16 is in turn connected to the parts 17 projecting from the sliders 4. The part 17 is also connected to the hoisting mechanism 6 which is formed by the hoisting cylinder 7 comprising the cilinder jacket 9 and the piston rod 10, both being pivotably mounted to the part 17 in the pivot 18 and the column 3 in the pivot 19, respectively. Obviously, the pivot 19 can also be connected to a fixed point of the container 12 of the vehicle 2. For pivoting the loading platform 5, the closing cylinder 8 is at one end pivotably connected to the loading platform 5 at the point 20, and at the other end to the slider 4 at the point 21. To that end, said slider 4 is provided with a U-shaped portion 15 extending around the hoisting cylinder 7 and carrying the lips 22, as it appears from Fig. 2. As it appears from Fig. 1, with the loading platform 5 in the vertical position, the axis 23 of the closing cylinder 8 will be in somewhat oblique position. The prolongation of the axis 23 will always be beyond the pivot 16, so that the loading platform 5 will not be blocked when the latter is pivoted downward. Here, it should be pointed out, that the location of the pivots can also be changed, since by the weight of the parts themselves, these will tend to move towards a certain position. For the supply of pressurized medium to the hoisting cylinders 7, there are flexible channels 14 which can be guided by the guides 13 which can be connected to the piston rods 10 of the pressurized medium cylinders 7. A channel 14 can also be connected to a piston rod 10 which then will be provided with a bore through which pressurized medium can be supplied to the space above the piston. For supply and discharge of pressurized medium to the various channels, one can employ connecting points 24 mounted at fixed locations. It will be obvious, that the pressurized medium cylinders 7 and the closing cylinders 8 can be connected to the various parts in the reverse position as well. When the loading platform 5 is in the position as shown in Fig. 1, sealing profiles 11 can be applied for realizing a seal between the loading platform 5 and the container 12 of the vehicle 2. In Fig. 2, the line 25 is indicated, being part of the plane in which the axes of the column 3, of the hoisting cylinder 7 and of the closing cylinder 8 are situated, said plane being about square to the pivot shaft 16.

Claims: Loading lift device (1) being mountable to the container (12) of a vehicle (2), said loading lift comprising two spaced-apart and parallel columns (3) being connectable to said container (12) in a substantially vertical position one at each side of the container opening, sliders (4) being mounted in or around said columns (3), a loading platform (5) being pivotably connected to said sliders (4) and being pivotably around a shaft (6) running square to the longitudinal direction of said sliders (4), saids loading platform (5) being pivotable over an angle of at least 90° from an operational position in which there can be a load on the loading platform (5) to an almost vertical position and vice versa, said sliders (4) being adjustable in height by means of at least one hoisting cylinder (7) extending substantially parallel to said column (3) and at one end being connected to said column (3) or to a fixed portion of said container (12) and at the other end to said slider (4), characterized in that the upper end of said hoisting cylinder (7) is connected to said column (3) or a fixed portion of the container (12) and the lower end to said slider (4) or a portion of the loading platform (5) fixedly connected to said slider (4), a closing cylinder (8) being present for pivoting said loading platform (5), said hoisting and closing cylinders (7,8) for moving said sliders (4) and for pivoting said loading platform (5) respectively being mounted such, that the axes of a column (3) and of its accompanying slider (4), of tee hoisting cylinder (7) and of the closing cylinder (8) are situated in a common plane (25) being almost square to the pivot shaft (16) of the loading platform (5), the pivot (21) between said closing cylinder (8) and said slider (4) being mounted to a connecting element (15) being formed such, that it extends along at least one side of said hoisting cylinder (7). Loading lift device according to claim 1, characterized in that each hoisting cylinder (7) is pivotably connected to the related slider (4) and to said column (3) either to said container (12). Loading lift device according to claim 1 or 2, characterized in that the part of the slider (4) being present outside said column (3) is tubular, said hoisting cylinder (7) connected to it being positioned, at least partially, inside said tubular part, the pivot (21) of said closing cylinder (8) being fixed to said tubular part. Loading lift device according to claim 3, characterized in that said tubular part of the slider (4) is forming part of said hoisting cylinder (7). Loading lift device according to one of the preceding claims, characterized in that the tube shaped portion of said hoisting cylinder (7) forms the lower end of it which is connected to said slider (4) either (4) to a portion of the loading platform (5) fixedly connected to said slider (4), said tube shaped portion being provided with the pivot (21) for said closing cylinder (8). Loading lift device according to one of the preceding claims, characterized in that said hoisting cylinder (7) and said closing cylinder (8) are single-acting pulling cylinders.

Inventors: NUYTS HENRI, NUYTS, HENRI
Applicants: NUYTS ORB
Application year: 1995
Main classification: B60P1
IPC codes: B60P1