Title of Invention

LIFT LOADING PLATFORM SYSTEM

Abstract

Lift loading platform system (1;1') for fixing on vehicles, with a platform (2) and a largely parallelogram-shaped lifting mechanism that comprises of two horizontally distanced support arms (3,3,4) for supporting the platform (2), a parallel cylinder (10) for swiveling the platform (2) from its vertical drive position to its horizontal working position and vice-versa, as well as a lifting cylinder (7) for lifting and lowering the platform (2) in its working position, whereby the lifting cylinder (7) grips on to a lifting cylinder lever (6) that can be rotated around the swivel axis (5) of the support arms (3,3',4), and forms a triangle of forces with it, and whereby the first support arm (3,3') is coupled elastically movable in lifting direction with the lifting cylinder lever (6) and the other second support arm (4) is connected to the lifting cylinder lever (6) by means of its torsion profile (9) characterized in that the elastic movement coupling is formed by a spring unit (8), that is supported one side to the first support arm (3,3') and on the other side to the lifting cylinder lever (6) or to the end of the lifting cylinder (7).

Full Text

FIELD OF THE INVENTION This invention relates to a lift loading platform system for fixing on to vehicles, with a platform and a largely parallelogram-shaped lifting unit that comprises of two horizontally distanced support arms for supporting the platform, a parallel cylinder for tilting the platform from its vertical running position to its horizontal working position and vice-versa, as well as a lifting cylincer for raising and lowering the platform in its working position, whereby the lifting cy inder grips on to a lifting cylinder lever that can be turned around the swivel axis of the support arms, and forms a triangle of forces with it, and whereby the first support arm is elastically coupled in a movable manner with the lifting cylinder lever in lifting direction and the other, second support arm is connected to the lifting cylinder lever by means of a torsion profile. PRIOR ART Such a lift loading platform system is, fcr example, known through EP-A-0 980 786. In the lift loading platform systems known from EP-A-0 980 786, the lifting cylinder lever is horizontally shifted against the allocated first support arm. The lifting cylinder lever and the first support arm are supported in a rotate-able manner around the common rotation axis, independent of one another, and connected to one another at a radial distance to the common rotation axis by a bolt, so that the platform-sided free end of the first support arm is coupled with the lifting cylinder lever in lifting direction, allowing elastic spring movement. After lifting the platform to the height of the truck loading- surface, a further lifting movement of the lifting cylinder lever is possible through further loading of the lifting cylinder; this movement is transmitted through the torsion pipe to the second support arm. In this way, one can achieve a clearance-free transition from the platform to the truck loading-floor, even in case of one-sided loading of the platform. Another lift loading platform system is known from EP-A-0 808 747, in which the first support arm is arranged between two parallel distanced arms. Both these arms form a triangle of forces with the lifting cylinder and are rotate-able around the rotation axis of both support arms. The first support arm is welded to both arms at a radial distance to its rotation axis by means of a cross traverse, so that its platform-sided free end can be coupled with the lift drive in lifting direction, with a provision for elastic spring movement. Besides, from EP-A-1 106 431 we know of a lift loading system, in which on to the arm forming a triangle of forces with the lifting cylinder a spring is supported that supports the platform at the other end. With the help of the spring the platform is coupled with the lifting drive, enabling an elastic spring movement in lifting direction. A lift loading platform system with a horizontal parallel arm arranged beside the first support arm is known from EP-A-1 221 399, that is supported rotate-able around the common rotation axis, independent the first support arm, and is connected at its other end to the first support arm by a universal joint. The lifting cylinder grips on to the universal joint between the first support arm and parallel arm. By means of a spring element that is supported on one side against the first support arm and, on the other side, against the torsion pipe, the first support arm is coupled with the lifting drive with the provision of a spring movement in lifting direction. Finally, another lift loading platform system is known from DE-C-102 05 669, in which the lifting cylinder grips on to the first support arm by means of an elastic compensation unit. The elastic compensation unit is supported in a rotate-able manner on the first support arm against the effect of a spring with the effect, that after lifting the loading platform up to the height of the truck loading-surface by further load on the lifting cylinder, the compensation unit gets further moved, against the effect of the spring. This movement gets transmitted by the torsion pipe to the second support arm. The task of this invention to is to further simplify a lift loading platform system of the type mentioned above. DESCRIPTION This task is fulfilled according to the invention, in that the elastic movement coupling is formed by its spring unit that is supported on the one side on the first support arm, and on the other side on the lifting cylinder lever or at the end of the lifting cylinder. In a preferred design form of the invention the first support arm and the lifting cylinder lever are supported rotate-able around the common rotation axis, independent of one another. In another preferred design form, the first support arm is supported rotate-able to its rotation axis at a radial distance (e.g. approx. 100 mm). The spring unit ideally has a compression spring, particularly a helical spring or a rubber suspension (e.g. of polyurethane). The lifting cylinder lever has two parallel, distanced arms, between which the first support arm is arranged. In order to avoid that both the arms of the lifting cylinder lever twist one another, on one arm of the lifting cylinder lever, particularly on the inner side arm, a connecting unit supporting the torsion profile is fixed, that rests on the other arm. Further advantageous extensions of the invention form the object of the sub-claims. One can see further advantages of the invention from the descriptions and the drawings. Similarly, the above-mentioned features and the features mentioned further below can find application, individually or severally, in various combinations. The design forms shown and described should not be taken as the final count, but are meant more as examples to describe the invention. DESCRIPTION OF THE ACCOMPANYING DRAWINGS The following are shown: Fig.l Schematically, a first design form of the lift loading platform system according to the invention, in which the first support arm and the lifting cylinder lever are supported rotate-able around a common rotation axis, independent of one another; Fig.2 Schematically, a second design form of the lift loading platform system according to the invention, in which the first support arm on the lifting cylinder lever is supported at a radial distance to its rotation axis, in a depiction analogous to fig. 1; Fig.3 A side view of the left support mechanism of the lift loading platform system shown in fig. 2, according to III in fig. 2, with a connecting unit not shown in fig. 2; and Fig.4 Top view of the left support mechanism of the lift loading platform system shown in fig. 3. In the schematically shown lift loading platform system 1 shown in fig. 1, depiction of the fixing on to the chassis frame has been left out on grounds of better overview. The system points supporting the platform 2 are A1 and B1, A2 and B2 as well as D1 and D2. The lift loading platform system 1 has a parallelogram-shaped lifting mechanism, whose basic elements are two support arms 3 ar d 4 that are supported in the fulcrum points A1 or A2 around the common rotation axis 5 in a swivel-able manner on the vehicle side. A lifting cylinder lever 6 and a lifting cylinder 7 are arranged below the first support arm 3. On the vehicle side, the lifting cylinder 7 is supported swivel-able around the fulcrum point C1 and the lifting cylinder lever 7 at A1 is supported swivel-able around its rotation axis 5, independent of the first support aim 3. The lifting cylinder 7 grips on to the lifting cylinder lever 6 at C2 and thus forms a tr angle of forces C1, C2, A1 with it. The force of the lifting cylinder 7 is introduced at the point C2 into the lifting cylinder lever 6 that describes a radius movement around its fulcrum point A1. Transmission of the rotation movement and the forces from the lifting cylinder lever 6 on to the first support arm 3 takes place through its spring unit 8 acting in between and on to the second support arm 4 through a relatively long torsion- and bending profile (torsion pipe) 9. As this additionally has the function of an undercarriage protection, it cannot lie in the region of both the support arms 3, 4 and is therefore fixed rotation-free below them respectively through connecting units (not shown in fig. 1) to the lifting cylinder lever 6 or to the second support arm 4. On account of the relatively big length of the torsion- and bending profile 9, for the same load, a greater torsion angle results. Naturally this deflection of forces has a much greater elasticity and therefore results in a greater elastic resilience, with the consequence of greater rotation angle of the second support arm 4 around its fulcrum point A2, as against the first support arm 3 around its fulcrum point A1. As the torsion pipe 9 is fixed to the lifting cylinder lever 6 and, depending on the load, goes beyond the rotation angle of the firs: support arm 3, the great torsion angle and the elasticity of the connecting unit get compensated thereby. In this way, one can achieve that, as a result, the first and second support arm 3, 4 move synchronously towards one another. A parallel cylinder 10 is pivoted on the vehicle side at the point B1 and on the platform 2 at D2 and has the functions like closing ofthe platform etc., that is generally known and therefore not discussed in details here. Besides, it serves the purpose of parallel guiding, and for that, is arranged shifted horizontally inwards with respect to the second support arm 4 and parallel to the second support arm 4. During the lifting and lowering movement, the parallel cylinder 10 acts as static pressure strut. The spring unit 8 is formed by a rubber suspension 11 that can be compressed to such an extent (max. spring path) till a stop stud of the lifting cylinder lever 7 comes to rest against a stop stud of the first support arm 3. The lift loading platform system 1' shown in fig. 2 differs from the lift loading platform system 1, merely in that the first support arm 3' on the lifting cylinder lever 6 is supported rotate-able at a radial distance (e.g. 100 mm) to its rotating axis 5 in the fulcrum point A1. After lifting the platform 2 to the height of the truck loading-surface, by applying further load to the lifting cylinder 7, a further lifting movement of the lifting cylinder lever is possible, that gets transmitted through the torsion pipe 9 on to the second support arm 4. This is applicable particularly to the unloaded platform. In this way, one can achieve a clearance-free transition from the platform 2 to the truck loading-floor, even if the platform 2 is loaded on one side, partly loaded or completely loaded. Fig. 3 shows that the torsion pipe 9 is fixed on the lifting cylinder side to the lifting cylinder lever 6 by means of a connecting unit 12. As shown in fig. 4, the lifting cylinder lever 6 is formed by two parallel, distanced arms 6a, 6b, between which the first support arm 3' is arranged. The connecting unit 12 comprises of two connecting plates 13, 14 bolted with one another. The connecting plate 13 is chamfered twice and has a large window 15, through which the first support arm 3', both the arms 6a, 6b of the lifting cylinder lever 6 and the lifting cylinder lever 7 stretch, and an upper strut 16 with which the connecting plate 13 is supported on both the arms 6a and 6b. The connecting plate 13 is fixed at a distance of 100 mm to the fulcrum point C3 of the lifting cylinder lever 6 by means of a continuous bolt 17 that goes through both arms 6a, 6b of the lifting cylinder lever 6, and has a distance (hollow)-pin 18 that distances both the arms 6a, 6b. On this distance pin 18, the first support arm 3' is supported that resis at its other end on the rubber suspension 11. The second fastening of the connecting plate 13 is done by a second bolt 19, which connects only the inner-side arm 6a of the lifting cylinder lever 6 with the connecting plate 13. This bolt joint is only required so that the connecting unit 12 cannot turn away upwards in case of external undercarriage protection forces and does not hit against the lifting cylinder piston rod with its lower region of the window 14. The working forces that get introduced from the lifting cylinder 7 or its triangular forces through the arms 6a, 6b of the lifting cylinder lever 6 into the connecting unit 12, go exclusively through the positive (shape-hugging) connection tha both the arms 6a, 6b transmit on to the upper strut 16 of the connecting unit 12. Without the support of the connecting plate 13 on the outer-side arm 6b, there is the danger that the entire lifting arm, i.e. support arm 3', arms 6a, 6b and the lifting cylinder 7 get twisted under lead due to the one-sided fastening of the connecting plate 13 on the inner-sided arm 6a. The connecting plate 14 is fixed to the first connecting plate 13 by means of two bolts 20. In the connecting plate 14, for one of the bolts, several fastening holes 21 are foreseen on the radius around the other bolt, in order to be able to shift the second connecting plate 14 and hence the torsion pipe 9 forming the andercarriage protection, to the height desired. Figures 3 and 4 further show the vehicle-side connecting flange 22, to which both the arms 6a, 6b of the lifting cylinder lever 6 and the lifting cylinder 7 are hinged. We claim: 1. Lift loading platform system (1;1') for fixing on vehicles, with a platform (2) and a largely parallelogram-shaped lifting mechanism that comprises of two horizontally distanced support arms (3,3',4) for supporting the platform (2), a parallel cylinder (10) for swiveling the platform (2) from its vertical drive position to its horizontal working position and vice-versa, as well as a lifting cylinder (7) for lifting and lowering the platform (2) in its working position, whereby the lifting cylinder (7) grips on to a lifting cylinder lever (6) that can be rotated around the swivel axis (5) of the support arms (3,3',4), and forms a triangle of forces with it, and whereby the first support arm (3,3') is coupled elastically movable in lifting direction with the lifting cylinder lever (6) and the other second support arm (4) is connected to the lifting cylinder lever (6) by means of its torsion profile (9) characterized in that the elastic movement coupling is formed by a spring unit (8), that is supported one side of the first support arm (3,3') and on the other side to the lifting cylinder lever (6) or to the end of the lifting cylinder (7). 2. Lift loading platform system as claimed in claim 1, wherein the first support arm (3) and the lifting cylinder lever (6) are hinged and rotateable around the common rotation axis (5), independent of one another. 3. Lift loading platform system as claimed in claiml, wherein the first support aim (3) is supported in a rotateable manner on to the lifting cylinder lever (6) at a radial distance to its rotation axis (5). 4. Lift loading platform system as claimed in one of the previous claims, wherein the spring unit (8) has a compression spring, particularly a rubber suspension (11). 5. Lift loading platform system as claimed in one of the previous claims, whereinthe lifting cylinder lever (6) has two parallel, distanced arms (6a,6b), between which the first support arm (3,3') is arranged. 6. Lift loading platform system as claimed in claim 5, wherein on one arm of the lifting cylinder lever (6), particularly on the inner-side arm (6a), a connecting unit (12) supporting the torsion profile (9) is fixed, which rests on the other arm of the lifting cylinder lever (6). 7. Lift loading platform system as claimed in claim 6, wherein the connecting unit (12) is fixed sideways on to the one arm of the lifting cylinder lever (6) and rests on both arms (6a,6b). 8. Lift loading platform system as claimed in claim 6 or 7, Wherein the connecting unit (12) has a connecting plate (13) with a window (15) through which the first support arm (3,3'), both the arms (6,6b) of the lifting cylinder lever (6) and the lifting cylinder (7) stretch, and with an upper strut (16) that rests on both arms (6a,6b). Lift loading platform system (1;1') for fixing on vehicles, with a platform (2) and a largely parallelogram-shaped lifting mechanism that comprises of two horizontally distanced support arms (3,3,4) for supporting the platform (2), a parallel cylinder (10) for swiveling the platform (2) from its vertical drive position to its horizontal working position and vice-versa, as well as a lifting cylinder (7) for lifting and lowering the platform (2) in its working position, whereby the lifting cylinder (7) grips on to a lifting cylinder lever (6) that can be rotated around the swivel axis (5) of the support arms (3,3',4), and forms a triangle of forces with it, and whereby the first support arm (3,3') is coupled elastically movable in lifting direction with the lifting cylinder lever (6) and the other second support arm (4) is connected to the lifting cylinder lever (6) by means of its torsion profile (9) characterized in that the elastic movement coupling is formed by a spring unit (8), that is supported one side to the first support arm (3,3') and on the other side to the lifting cylinder lever (6) or to the end of the lifting cylinder (7).

Documents:

234-KOLNP-2006-FORM 27 1.1.pdf

234-KOLNP-2006-FORM 27.pdf

234-kolnp-2006-granted-abstract.pdf

234-kolnp-2006-granted-claims.pdf

234-kolnp-2006-granted-correspondence.pdf

234-kolnp-2006-granted-description (complete).pdf

234-kolnp-2006-granted-drawings.pdf

234-kolnp-2006-granted-examination report.pdf

234-kolnp-2006-granted-form 1.pdf

234-kolnp-2006-granted-form 18.pdf

234-kolnp-2006-granted-form 2.pdf

234-kolnp-2006-granted-form 26.pdf

234-kolnp-2006-granted-form 3.pdf

234-kolnp-2006-granted-form 5.pdf

234-kolnp-2006-granted-reply to examination report.pdf

234-kolnp-2006-granted-specification.pdf

234-kolnp-2006-granted-translated copy of priority document.pdf