The present invention relates to an improved lift for motor vehicles.

Parallelogram and pantograph vehicle lifts are known comprising a pair of longitudinal members resting on the floor, a pair of horizontal runways raisable relative to the longitudinal members to lift the vehicle positioned on them, and with raising devices or uprights, pivoted in the manner of a parallelogram or pantograph to the runways and to the longitudinal members and operated by generally hydraulic systems to raise the runways.

These known types of lifts have been widely used essentially for their ease of installation, their robustness and their operational reliability.

In particular, known lifts include those in which each runway is provided with a single raising device. In these lifts the runways are particularly short (of about 2 metres), this being necessary to ensure its balanced raising by a single device. Inevitably these lifts are unable to lift the vehicle wheels, but only its body.

In addition, known vehicle lifts include those in which each raising device comprises:

- first and second main arms of equal length hinged together at one end, and hinged at their other end respectively to the floor and to the runway about two vertically superposed transverse axes,

- first auxiliary arms hinged to second auxiliary arms and to the first main arms,

- second auxiliary arms hinged to the first auxiliary arms at one end and to the second main arms at an intermediate portion, and slidingly engaged at the other end along a guide provided in the corresponding runway, - an actuator positioned between the main arms and the secondary arms or auxiliary arms.

These known vehicle lifts do not ensure satisfactory stability under all operating and load conditions, given that their raising devices rest on the floor only with the lower end of their first main arms.

An object of the invention is to provide a vehicle lift which is more stable than traditional lifts, while presenting a configuration such as to optimize the distribution of the load to be lifted on the arms of their raising devices.

Another object of the invention is to provide a vehicle lift which is able to lift the vehicle by supporting it at its wheels.

Another object of the invention is to provide a vehicle lift which is able to compensate deformations and misalignments and to avoid internal overloading of the various structural components.

Another object of the invention is to provide a vehicle lift which can assume a deformed geometry and/or can absorb unbalanced loads while always ensuring its stability in the raised condition and without generating structural overloads.

Another object of the invention is to provide a lift which rises with perfectly vertical travel and is easily accessible, both longitudinally and transversely, to the operators who are required to work below the raised lift.

Another object of the invention is to provide a lift which enables the operators to pass across and/or utilize the space interposed between the two runways Another object of the invention is to provide a vehicle lift having an alternative characterisation, both in constructional and functional terms, compared with traditional vehicle lifts.

Another object of the invention is to provide a vehicle lift which is easily installable within the room in which it is intended to be positioned.

Another object of the invention is to provide a lift of easy, quick and low- cost construction.

These objects are attained, according to the invention, by a vehicle lift with the characteristics indicated in claim 1 .

The present invention is further clarified hereinafter in terms of a preferred embodiment thereof, described by way of non-limiting example with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a vehicle lift according to the invention in the raised condition,

Figure 2 is a front view of a runway with the corresponding raising device, Figure 3 is a lateral view of the vehicle lift in the raised condition,

Figure 4 shows it in the lowered condition,

Figure 5 shows an enlarged detail of Figure 3, and

Figure 6 shows the same enlarged detail as Figure 4,

As can be seen from the figures, the vehicle lift 1 according to the invention comprises substantially a pair of runways 2 raisable relative to the floor 3 by raising devices indicated overall by 4.

Two raising devices 4 are associated with each runway 2 and act on the end regions of the runway. Each runway 2 is suitably shaped and dimensioned to receive the wheels of the vehicle to be lifted. In particular, each runway 2 consists of a metal plate bent to inverted U-shape with lateral flanges and a central web which defines a lower surface for supporting the vehicle wheels. Preferably, the height of the lateral flanges of each runway 2 is defined such as to be substantially equal to or slightly greater than that of the raising device 4 when in its folded condition.

Appropriately, each runway 2 has a length such as to receive all the wheels located on the same side of the vehicle to be lifted, for example of about 7 metres.

Preferably, the two parallel longitudinal runways 2 have no transverse mechanical connections between them.

In particular, each of the two raising devices 4 of each runway 2 comprises a lower main arm 6, which is hinged at its upper end about a pin 9 to an upper main arm 8, and is hinged at its lower end to a hinge bracket 12 fixed to the floor 3 of the installation room.

The upper main arm 8 has the same length as the lower main arm 6 and, as stated, has its lower end hinged to the upper end of the lower main arm 6, and its upper end hinged to the runway 2.

Each raising device 4 also comprises a lower auxiliary arm 20 which, at its lower end, is provided with rollers or slide blocks 22 slidable on the floor 3, and at its upper end is hinged to an upper auxiliary arm 24 about a pin 23.

Preferably, the rollers or slide blocks 22 are slidable along guides defined on a base longitudinal member 29 fixed to the floor 3, and to which the hinge bracket 12 is also suitably fixed. In addition, the lower auxiliary arm 20 is hinged to the lower main arm 6 about a first pin 26 interposed between the two ends of the arm 20, in a position such that the two portions of lower main arm 6 and of lower auxiliary arm 20 included between their hinge pin 26 and the respective lower ends are equal.

The upper auxiliary arm 24 has its lower end, as already stated, hinged to the lower auxiliary arm 20, and its upper end hinged to the upper main arm 8 about a second pin 28, interposed between the two ends of said upper main arm 8.

The hinge pins 9, 26, 23 and 28 between the main arms 6 and 8 and the auxiliary arms 24 and 20 are positioned such that the figure defined by them is a parallelogram.

Each raising device 4 also comprises an actuator 30, preferably consisting of a cylinder 32 with relative piston of oil hydraulic operation. The cylinder has its lower end hinged at 31 to the lower main arm 6, while its piston rod 34 has its upper end hinged at 33 to the upper main arm 8.

In greater detail, the pin 31 about which the actuator 30 is hinged to the lower main arm 6 is positioned between the pin 26 about which the lower auxiliary arm 20 is hinged to the lower main arm 6 and the pin 9 about which the two main arms 6 and 8 are hinged together, while the pin 33 about which the piston rod 34 is hinged to the upper main arm 8 is positioned between the pin 28 about which the upper auxiliary arm 24 is hinged to the upper main arm 8 and that end of this upper main arm 8 hinged to the runway 2. However, in a different embodiment, not shown in the drawings, the hinge pin 31 of the actuator 30 could be positioned between the pin 26 and the hinge bracket 12, and the hinge pin 33 of the piston rod 34 could be positioned between the pin 9 and the pin 28. What is important is that the actuators 30 are interposed between the two main arms 6 and 8.

The actuators 30 of the raising devices 4 associated with the same runway 2 are suitably controlled such as to ensure their simultaneous and equal actuation, in order to guarantee that the runway undergoes only translatory motion during its rising and descent.

In greater detail, for this purpose, the cylinders 32 of the actuators 30 are fed by a hydraulic circuit, not shown, by means of a flow divider controlled such as to ensure simultaneous and equal movement of the piston rods 34 within the respective cylinders 32. These could moreover be controlled just as effectively by an electronic balancing system.

In any event, the actuators, and their control, are of known type and as such will not be further discussed. However, by way of example, reference can be made to that described in invention patent application VE2007A000059 filed on 20 August 2007 in the name of the same applicant.

Advantageously, all the main arms 6 and 8, and all the auxiliary arms 20 and 24 can consist of two identical plates facing each other, connected together spaced apart by transverse plates. In this manner, each arm defines between two facing plates a suitable space in which the actuator 30 is positioned.

The vehicle lift according to the invention operates in the following manner: with the lift in the lowered condition (see Figures 3 and 5), the actuators 30 are in their minimum elongation condition. In this condition, the vehicle (not shown in the drawings) can be made to rise onto the runways 2. To raise the lift, the actuators 30 are activated, and as they gradually extend (see Figures 1 and 2), the following takes place by virtue of the particular choice of the hinge points:

- the main arms 6, 8, which with the lift in the lowered configuration are virtually coplanar, rotate in the sense of increasing the angle formed between them; in particular, the elongation of the actuator 30 causes each upper main arm 8 to rotate and withdraw from the respective lower main arm 6;

- the arms 20, 24 also rotate in the sense of increasing the angle formed between them; in particular, the rotation of each upper main arm 8 causes the respective upper auxiliary arm 24 to rotate and withdraw from the lower auxiliary arm 20, which also rotates by the effect of the raising of the lower main arm 6, to which it is hinged about the first hinge pin 26.

Moreover, while the upper auxiliary arm 24 rotates about the corresponding lower auxiliary arm 20, the lower end of this latter, provided with rollers or slide block 22, slides on the floor 3, or on suitable guides 29, hence approaching the hinge bracket 12.

The result is that the runways 2 move upwards relative to the floor 3 while remaining parallel to this latter. The presence of a suitable controller for the actuators 30 ensures synchronism of movement of all the raising devices 4 which act on the two runways.

In particular, the vehicle lift according to the invention differs from traditional lifts by being of the type in which each runway is provided with two raising devices which are spaced balanced along the direction of longitudinal extension of the runway and, principally, for the fact that each upper auxiliary arm is hinged at its upper end to the upper main arm, i.e. without extending as far as being hinged to the runway itself. This makes the lift simpler, lest costly and less heavy, ensuring at the same time its high stability.

Moreover, from the aforegoing, it is apparent that the vehicle lift according to the invention is more advantageous than traditional lifts, in that: - because of the absence of mechanical impediments at floor level between the raising devices, the operators are ensured free access both longitudinally and transversely below the raised lift,

- as each raising device 4 is doubly supported on the floor, high stability of the lift is ensured under any raised condition,

- by virtue of the direct connection of each actuator 30 to the two main arms of each raising device 4, easy construction of the lift is ensured, without the need for any auxiliary linkage.