VEHICLE LIFT OF THE TYPE WITH FOUR COLUMNS

Abstract: A description is provided of a vehicle lift (10) of the type with four columns, in which the vertical movement of the cross-beams (14) and of the runways (16) along the columns (12) is controlled by means of two pistons (18), each of which is accommodated inside a respective cross-beam (14), of which it controls the movement. The lift (10) provides considerably simplified assembly, and the possibility of replacing or displacing the runways (16).

Description: Title: "VEHICLE LIFT OF THE TYPE WITH FOUR COLUMNS" TEXT OF THE DESCRIPTION The present invention relates to vehicle lifts of the type with four columns. In known vehicle lifts with four columns, the vertical movement of the cross-beams along the columns, and thus the vertical movement of the runways which support the vehicles, is controlled by means of a single piston which is accommodated beneath one of the runways. It is thus necessary to have a series of cables and return pulleys, which result in extremely difficult and lengthy assembly of the lift. In addition, the size and arrangement of the runways is restricted, owing to the traction cables themselves, such that adaptation of the runways substantially requires re-assembly of the entire lift. The object of the present invention is to provide a vehicle lift of the type with four columns, which permits easier assembly, and also makes it possible to make the size and arrangement of the runways independent' from the assembly of the lift itself. This problem is solved remarkably well by means of a vehicle lift according to claim 1, of the type with four columns. Further advantageous characteristics of this lift are indicated in the dependent claims . The characteristics, objects and advantages of the present invention will become more apparent from the following description and from the attached drawings, provided with reference to a non-limiting embodiment. In the various figures: Figure 1 is a schematic perspective view of a vehicle lift with four columns according to the prior art; Figure 2 is a schematic perspective view of a vehicle lift with four columns according to the present invention; and Figure 3 is a schematic view of the system of cables and lifting pulleys in figure 2. With reference firstly to figure 1, a vehicle lift 100 with four columns, which represents the state of the art, has firstly four columns 112. Two cross-beams 114 are disposed between a respective pair of adjacent columns, and two runways 116 to support the vehicle are disposed transversely relative to the cross-beams 114. The vertical movement of the cross-beams 114 along the columns 112, and thus the vertical movement of the runways 116 which support the vehicles, is controlled by means of a single piston 118, which is actuated by corresponding actuation means 120. The piston 118 is accommodated beneath one of the runways 116. As a result of this arrangement of the piston 118, it is necessary to have a series of cables and return pulleys, which make it possible to transform the movemen ' t of the rod of the piston 118 into a synchronous vertical movement of the cross-beams 114, and thus of the runways 116. The assembly of the lift 100 according to the known art is thus extremely difficult and lengthy, since it is necessary to pass the cables around the pulleys and along the crossbeams 114, and to adjust their length after positioning of the runways 116, or at least of the runway beneath which the piston 118 is accommodated. In addition, the runways 116 cannot be replaced or displaced without virtually having to reassemble the entire lift 100. Figure 2 illustrates a vehicle lift 10 of the type according to the present invention, with four columns. The components of the lift 10 which correspond to those of the lift 100 in figure 1 have corresponding reference numbers, but reduced by 100, such that a detailed description of the lift 10 is omitted for the sake of brevity. According to the invention there are provided two pistons 18 (of which only one is shown) , each of which is accommodated inside a cross-beam 14. As illustrated more clearly in figure 3, each piston 18 controls the vertical movement of the corresponding cross-beam 14 by means of two lengths of cable 22, 24. The length of cable 22 which is drawn as an unbroken line passes around a first pulley 26, which is connected to the piston rod 18, runs along the piston 18 itself, and is deflected by 90° by a second pulley 28, and then extends along the column 12, whereas the length of cable 24 which is shown as a broken line, runs along the other side of the piston 18, passes around a third pulley 30, runs along the cross-beam 14, and is finally deflected by 90° by a fourth pulley 32, and then extends along the other column 12. It will thus be appreciated that the movement along the columns 12 is doubled in relation to the path of the piston 18. In practice, a path of approximately 90 cm is sufficient, i.e. which is reduced by half in relation to the piston 118 of the known lifts 100. The lift 10 according to the present invention has an assembly which is considerably simplified, since the two systems of pistons, cables and pulleys for the two crossbeams 14 are independent, except that, it will be appreciated, means (not shown) must be provided for synchronisation of the movement of the two pistons 18. In addition, the assembly is altogether independent from the runways 16, which can thus easily be replaced or re- positioned in order to adapt them to the type and gauge of the vehicle, such that they can also be assembled in a sliding manner along the cross-beams 14. Finally, this greater versatility provides advantages of production and storage, since the same cross-beam systems can be used for different lift models. Persons skilled in the art will appreciate that many modifications, adaptations, completions, variants and replacements can be made to the embodiment previously described by way of non-limiting example, without departing from the scope of the invention as determined by the following attached claims.

Claims: CLAIMS 1. Vehicle lift (10) of the type with four columns, comprising four columns (12) , two cross-beams (14) which are disposed between a respective pair of adjacent columns, and two runways (16) to support the vehicle, which are disposed transversely relative to the cross-beams (14) , wherein the vertical movement of the cross-beams (14) and of the runways (16) along the columns (12) is controlled by means of a piston (18) , cables and pulleys (22-32) , characterised in that the said piston means comprise two pistons (18) , each of which is accommodated inside a respective cross-beam (14) , of which it controls the movement . 2. Lift (10) according to claim 1, characterised in that the said cable and pulley means (22-32) which are associated with each piston (18) comprise a length of cable (22) which passes around a first pulley (26) , which is connected to the rod of the piston (18) , runs along the piston (18) , and is deflected by 90° by a second pulley (28), and then extends along a first column (12), and a length of cable (24) which runs along the other side of the piston (18) , passes around a third pulley (30) , runs along the cross-beam (14) and is deflected by 90° by a fourth pulley (32) , and then extends along the other column (12) . 3. Lift (10) according to claim 1 or claim 2, characterised by means for synchronisation of the movement of the two pistons (18) . 4. Lift (10) according to any one of the preceding claims, characterised by a plurality of pairs of runways (16), which can be replaced according to the vehicle. 5. Lift (10) according to any one of the preceding claims, characterised in that the runways (16) are assembled in a sliding manner along the cross-beams (14) .

Inventors: GRANATA TEBALDO, GRANATA, TEBALDO
Applicants: GRANATA TEBALDO, SNAP ON TECH INC, GRANATA, TEBALDO, SNAP-ON TECHNOLOGIES, INC.
Application year: 1999
Main classification: B66F7
IPC codes: B66F7