The present invention relates to a hydraulic lift.

Lifts of the winch type are known, said machines requiring the presence of an upper compartment or a machine room for the winch and a lower compartment for inspection purposes. These lifts are somewhat costly and normally require the presence of said two additional compartments at the ends of the cage travel path.

Hydraulic lifts comprising a cage which is designed for the transportation of persons or objects and is supported and moved, directly or indirectly, by means of one or more pistons sliding inside respective fixed cylinders, positioned laterally with respect to the cage or underneath it, are known. There exist lifts or elevators in which the pistons operate under traction during raising of the cage, and others in which said pistons operate under compression or thrust. It is necessary, however, for there to be a machine room for housing the means for moving the pistons (motor and pump) as well as the solenoid valve group and the electric control panel. A further lower compartment is also envisaged so as to allow the descent of the cage below the bottom floor as far as the bottom end-of- travel stop.

In these hydraulic or oil-operated lifts there is normally a motor which actuates a pump which removes oil from a tank and conveys it into a pressure circuit and into the cylinder in order to raise the cage, while normally during the downward travel the motor is at a standstill, the oil returns into tank without any energy consumption and the downward movement is caused by the weight of the cage and the cage supporting means.

The valve group, which may be of the mechanical or electronic control type, controls the flow of the oil during both the upward movement and the downward movement of the cage, controlling the speed thereof until it reaches the desired floor. Said group is

associated with a container/tank which contains the motor and the pump and is positioned in a special machine room which may also be located at a distance from the cylinder or from the cylinders and is normally situated at the bottom floor of the lift travel path.

Normally, in the case of indirect supporting of the cage and the lateral cylinder, the stroke of the cylinder is equal to half the stroke of the cage or even less, by means of a system of tackles with pulleys.

DISCLOSURE OF INVENTION.

The object of the present invention is that of eliminating the abovementioned drawbacks and in particular the need for a special machine room, by providing a hydraulic lift which is able to incorporate motor and pump inside the well provided for the lift itself, by positioning the central supply unit and the electric control panel outside.

A further object is that of achieving this in an extremely simple and low-cost manner.

Said objects are fully achieved by the hydraulic lift, according to the present invention, which is characterized by the contents of the claims indicated below and in particular by the fact that the motor and the pump are formed so as to be positioned inside the lift well, while the central supply unit with the solenoid valves and the operating panel are housed in a special recess which is accessible from outside the well and are connected to the drive system inside the well by means of cables and by means of pipes for the oil or other fluid.

The fluid storage tank is also positioned inside said well and may be fixed both alongside the travel path of the cage and in a pit at the bottom of the well and may be formed so as to comprise a first portion positioned in the well laterally with respect to the travel path of the cage and a second portion positioned underneath the bottom end-of-travel stop of the cage travel path.

The central supply unit with the control solenoid valves and a manually actuated pump, as well as an electric or electronic operating panel, may be housed in a special cabinet

provided with a hatch, which is positioned outside the well, or may be housed inside a recess formed directly in the doorway of one of the floor access doors of the lift. This recess may also be provided with sound-damping or acoustic insulating means.

BRIEF DESCRIPTION OF DRAWINGS.

These and other characteristic features will emerge more clearly from the following description of a preferred embodiment illustrated, purely by way of a non-limiting example, in the accompanying plates of drawings, in which: -Figures 1 and 2 show schematically the lift, with the cage in the low and high position, respectively; -Figure 3 shows a plan view of the lift; -Figure 4 shows schematically the connections between elements forming the lift.

BEST MODE FOR CARRYING OUT THE INVENTION.

With reference to the Figures, 1 denotes in its entirety a hydraulic lift comprising a cage 2 which travels upwards and downwards inside a well 3, being moved by a piston 4 of an oil-operated cylinder 5. In the example shown there is only one cylinder, which is positioned laterally with respect to the cage, the piston of which supports and moves the cage indirectly by means of pulleys 6 and cables 7 in accordance with a known technology, but also several oil-operated cylinders may be used, operating under traction or compression/thrust.

8 denotes a counterweight associated with the piston, while 9 denotes the walls of the well 3 of the lift and 10 the guides for sliding of the cage. 11 and 12 denote respectively the cage doors (for example of the sliding leaf type) and a floor access door.

13 denotes a container which is arranged in a original manner inside the well 3 of the lift and comprising internally an electric motor and a pump actuated by the abovementioned motor and intended to draw fluid (normally oil) from a tank (which in the specific case

is the container 13 itself) so as to convey it into a pressure circuit for actuation of the oil- operated cylinder 5.

14 denotes an electrical connection box mounted directly onto the container 13, while an operating panel 15 of the electrical or electronic type is housed, in an original manner, in a recess 16 which, in accordance with that shown in Figure 3, is formed directly in the wall alongside the floor access door (normally the wall corresponding to the first bottom stopping point of the lift) and is protected by a closing hatch 17 which allows access to the operating panel 15 from outside the well 3. The recess 16 in some cases may be formed in the doorway of the floor access door 12 or also may be formed in a special cabinet 18 mounted outside the well 3, in accordance with that shown schematically in Figure 4.

In all cases the recess 16 houses in an original manner also a central supply unit 19 comprising a valve group of the mechanical or electronic type and an emergency manual pump not shown in detail since it is of the known type. The operating panel 15 is connected electrically to the central supply unit 19 by means of electrical cables 20.

The recess 16 may, if necessary, be divided up into two sections, one for the operating panel and the other for the central supply unit, by means of a separation baffle 23.

The central supply unit 19 comprises a valve for the upward travel of the cage, one for the downward travel and one for emergencies and is connected in a known manner to the oil- operated cylinder 5 and to the drive system enclosed in the container 13. The container 13 also acts as a storage tank for the oil and or other fluid used and therefore the pump and the motor are immersed in an oil bath. In a variation of embodiment, not shown, it is envisaged that the motor may be external with respect to the container 13, but in any case positioned inside the well 3.

Obviously, since the central supply unit, unlike the known art, is not mounted directly on

the container 13, but is located outside the well 3 inside the recess 16, the electrical cables and the fluid pipes necessary for connection with the drive system enclosed in the container 13 are longer, even though, however, they may be limited to about 1.5 to 2 metres in length.

The recess 16 may be acoustically isolated by using insulation consisting of sound- damping material in order to prevent the noise of the solenoid valves of the central supply unit and the remote control switches of the operating panel from creating disturbance to persons living in adjacent premises.

Moreover, in order to make better use of the available space, it is possible for the container 13 (which also acts as a storage tank for the fluid) to have a particular shape, for example to be"L"shaped so that it can be partially inserted underneath the bottom end-of- travel stop of the cage (shown in broken lines in Figure 3) and remain partly lateral with respect to the cage itself (visible in solid lines in Figure 3) in the zone of the well where the guides 10 are not present.

The tank, according to a variation of embodiment not illustrated, may be positioned in a niche-if necessary insulated-formed in one of the walls of the well 3 of the lift.

21 denotes pipes for the fluid which, according to a known technology, comprise a delivery pipe, a return or discharge pipe and a pipe connected to the oil-operated cylinder, while 22 denotes electrical cables for connecting the operating panel 15 and the electrical connection box 14.

Basically, in a hydraulic lift of the known type, the Applicant has devised in an original manner a solution which makes it possible to avoid the use of a special machine room for housing the drive system and the means for controlling the fluid flow (operating panel and central supply unit).

The innovative idea is that of positioning the container/tank 13, together with the motor

and pump inside the well 3 of the lift, arranging outside not in a machine room but in a simple recess (formed in the wall or consisting of a special cabinet), both the operating panel and the central supply unit with the solenoid valves and the manually actuated emergency pump.

A further advantage may be achieved with the use of a particular configuration of the container/tank located partially underneath the cage.