TECHNICAL FIELD

The present invention relates to a tracked vehicle, a power supply apparatus for powering the tracked vehicle and a handling system in a work area comprising the tracked vehicle and the power supply apparatus of the tracked vehicle.

BACKGROUND ART

A tracked vehicle is known from document WO 2010/103117 that has a first and a second track, an internal combustion engine, a set of working devices and an electric power transmission that connects the internal combustion engine to the first and second tracks.

One drawback of this solution is that the tracked vehicle is noisy. Another drawback of the known art is that the tracked vehicle has emissions that pollute the environment in which it is working. Another drawback of the known art is that the internal combustion engine of the tracked vehicle needs relatively expensive routine maintenance. Yet another drawback of the known art is that the tracked vehicle has a relatively high cost.

DISCLOSURE OF INVENTION

One object of the present invention is to provide a tracked vehicle that overcomes at least one of the drawbacks of the known art .

According to the present invention, a tracked vehicle is provided that comprises an electric machine assembly, at least one track coupled to the electric machine assembly, and an electric connection device, connectable to a power supply apparatus outside the tracked vehicle and connected to the electric machine assembly, to exchange electrical energy with the power supply apparatus during operation of the tracked vehicle .

Thanks to the electric connection device, the tracked vehicle exchanges electrical energy with the outside during operation and, in this way, reduces both noise and atmospheric pollution in the place where used.

Another object of the present invention is to provide a power supply apparatus to power a tracked vehicle inside a work area and which reduces at least one drawback of the known art. According to the present invention, a power supply apparatus is provided for supplying power to a tracked vehicle inside a work area, wherein the apparatus comprises a supply system configured to be connected to the tracked vehicle according to any of claims 1 to 9.

Another object of the present invention is to provide a handling system inside a work area that reduces at least one drawback of the known art. According to the present invention, a handling system is provided inside a work area comprising a tracked vehicle according to any of claims 1 to 9 and a power supply apparatus according to any of claims 10 to 19. BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the present invention will become clear from the following description of a non- limitative embodiment, with reference to the accompanying drawings, in which:

- Figure 1 is a perspective view of a handling system inside a work area comprising a tracked vehicle and a power supply apparatus for the tracked vehicle made in accordance with the present invention;

- Figure 2 is a side view, with parts removed for clarity, of the tracked vehicle in Figure 1 ;

- Figure 3 is a side view, with parts removed for clarity, of the tracked vehicle in Figure 1 in a different operating configuration with respect to Figure 2; and

- Figure 4 is an enlarged view of a detail in Figure 1. BEST MODE FOR CARRYING OUT THE INVENTION

Referring to Figure 1, reference numeral 1 defines, as a whole, a handling system inside a work area P comprising a tracked vehicle 2, a power supply apparatus 3 for powering the tracked vehicle 2 and a control unit 16. In a non-limitative embodiment of the present invention, the work area P is on soft ground or loose soil. By way of a non-limitative example of the present invention, the tracked vehicle 2 shown in the accompanying drawings is a snow groomer and the work area P is a ski run, in particular a cross-country ski run or a downhill ski run. Furthermore, the work area P can be a covered or an open work area.

In one embodiment, the control unit 16 is housed in the tracked vehicle 2. In another embodiment, the control unit 16 is housed in the power supply apparatus 3. In yet another embodiment, the control unit 16 is housed externally to the tracked vehicle 2 and to the power supply apparatus 3.

Referring to Figures 2 and 3, the tracked vehicle 2 comprises: an electric machine assembly 4; two tracks 5 and 6 (Figure 1) coupled to the electric machine assembly 4; a plurality of working devices 7 connected to the electric machine assembly 4; and an electric connection device 8, connected to the power supply apparatus 3 of the tracked vehicle 2 and connected to the electric machine assembly 4 to exchange electrical energy with the power supply apparatus 3 of the tracked vehicle 2 during operation of the tracked vehicle 2. In other words, the tracked vehicle 2 moves inside the work area P and is simultaneously powered by electrical energy taken from the power supply apparatus 3.

In an alternative embodiment, not shown in the accompanying drawings, the tracked vehicle comprises only one track.

The electric machine assembly 4 comprises at least one electric machine and at least one converter that receives electrical energy from the electric connection device 8 and supplies the electrical energy to the at least one electric machine. In greater detail, the electric machine is indirectly connected by a wheel and/or a mechanical transmission unit not shown in the accompanying drawings .

In one embodiment, the electric machine 4 is a direct current electric machine. In another embodiment, the electric machine 4 is a synchronous or asynchronous alternating current electric machine. In an alternative embodiment of the present invention, not shown in the accompanying drawings, the tracked vehicle comprises an electric machine that supplies kinetic energy to a hydraulic pump, which in turn supplies power to a hydraulic motor.

In a preferred embodiment of the present invention, the electric machine assembly 4 comprises two electric machines, each coupled to a respective track 5 and 6. In addition, the electric machine assembly 4 is reversible, in other words, it can function both as an electric motor and as an electric generator. When electric machine assembly 4 functions as an electric motor, it takes electrical energy from the electric connection device 8 and supplies kinetic energy to the tracks 5 and 6. When the electric machine assembly 4 functions as an electric generator, it receives kinetic energy from the tracks 5 and 6, for example to brake the motion of the tracked vehicle 2, and supplies electrical energy to the electric connection device 8, which in turn feeds it to the power supply apparatus 3.

The electric connection device 8 comprises an electric cable 9 connectable to the power supply apparatus 3 of the tracked vehicle 2 and partially wound around a winch 10. The length of the electric cable 9 is greater than 25 metres, preferably greater than 50 metres, to ensure operation of the tracked vehicle 2 while it is connected to the power supply apparatus 3 and to ensure that the tracked vehicle 2 can move between the lateral limits of the work area P. The electric cable 9 comprises two conductor cores separated from one another to carry the phase and earth of the electric current, or the positive pole and the negative pole. In an alternative embodiment of the present invention, the electric cable 9 comprises three conductor cores separated from one another to carry a three-phase current.

In an alternative embodiment of the present invention, the electric cable 9 comprises only one conductor core, which carries the phase of the electric current. In said embodiment, the earth for the electric current is connected to the ground S in various points and the tracked vehicle 2 is connected to the earth of the tracked vehicle 2 running to the ground S.

Furthermore, the electric connection device 8 comprises the winch 10 configured to wind part of the electric cable 9 and an arm 11 to lift the electric cable 9 to a given height off the ground. In particular, the arm 11 comprises two folding elements 11a and lib in order to vary the distance from the ground S. In an alternative embodiment of the present invention, not shown in the accompanying drawings, the arm 11 is a telescopic arm configured to extend or retract in order to vary the distance from the ground S. In addition, the electric connection device 8 comprises a tensioning unit 12 for the electric cable 9 that acts on the winch 10, comprises a mechanical tension meter 10a for the electric cable 9 and is coupled to the winch 10 to keep the mechanical tension of the electric cable 9 within a given operating range. In other words, the winch 10 is controlled by the tensioning unit 12 so that the electric cable 9 has a mechanical tension within the given operating range of mechanical tension. Thanks to the tensioning unit 12, the electric connection device 8 ensures that the electric cable 9 does not touch the ground S. Furthermore, thanks to the tensioning unit 12, the electric connection device 8 ensures that the electric cable 9 does not break or become disconnected from the power supply apparatus 3. In addition, the electric connection device 8 comprises a shutdown switch 13 that is operated when the electric cable 9 has a mechanical tension different from the values in an operating range of mechanical tension. Furthermore, in the case where the electric voltage is different from the values in an operating range of electric voltage, the shutdown switch 13 operates to disconnect the electric cable 9.

In addition, the electric connection device 8 comprises a measuring device 14 that allows measuring the length of the unwound electric cable 9. For example, the measuring device 14 is an encoder coupled to the winch 10 that measures the number of turns and direction of rotation of the winch 10. Thanks to the measuring device 14, it is possible to derive a measurement of the distance of the tracked vehicle 2 from the power supply apparatus 3.

The electric connection device 8 is connected to the control unit 16 to transmit and receive data. The electric connection device 8 sends the measurement of the length of unwound electric cable 9 to the control unit 16. In an alternative embodiment of the present invention, the tracked vehicle 1 comprises a battery 15 (shown with broken lines in Figure 2 and 3) configured to allow the tracked vehicle 1 to have a short period of autonomy in the event of manoeuvres in a depot or to move from one power supply apparatus 3 to another power supply apparatus.

Referring to Figure 1, the power supply apparatus 3 of the tracked vehicle 2 comprises a supply system 20 configured to be connected to the tracked vehicle 2, and a slider 22 connected to the supply system 20 and movable along the supply system 20. In greater detail, the supply system 20 extends along a path PI and comprises two conductive elements 21 to carry the phase and earth of the electric current and supports 21a that support the two conductive elements 21 at a given height off the ground S, preferably greater than 2.5 metres.

In an alternative embodiment of the present invention, not shown in the accompanying drawings, the supply system 20 comprises three conductive elements 21 configured to carry a three-phase current.

In a preferred version of the present invention, the path PI extends laterally to the ski run P.

In an alternative version of the present invention, not shown in the accompanying drawings, the conductive elements 21 are supported by the supports of a ski lift or a lighting system.

In an alternative embodiment, not shown in the accompanying drawings, one of the two conductive elements 21, in particular the conductive element 21 that carries the phase of the electric current, is supported by the supports 21a and fastened at a given height off the ground, and the other conductive element 21, which carries the earth, is connected to the ground S . In a preferred embodiment, shown in Figure 1, the conductive elements 21 preferably comprise two cables of an electrically conductive material capable of supporting the slider 22. In another embodiment, the conductive elements 21 are rails made of an electrically conductive material and are capable of supporting the slider 22.

In one embodiment of the present invention, the conductive elements 21 are made of a luminous material so as to visible in the dark or in poor light conditions. In another embodiment, the conductive elements 21 are coated with a fluorescent material. In yet another embodiment, the conductive elements 21 comprise LEDs . Thanks to the luminous conductive elements 21, it is possible to see the conductive element 21 in any lighting condition, thus facilitating coupling with the tracked vehicle 1 and reducing hazardous situations due to accidental contact with the conductive element 21.

Referring to Figure 1, the slider 22 is defined by a trolley 22 coupled to the supply system 20 and configured to move along the path PI. The trolley 22 comprises a connector 23 rotating about an axis Al perpendicular to the conductive elements 21 and passing through the ground S. Furthermore, the connector 23 is configured to be connected to the electric connection device 8 of the tracked vehicle 2 and to allow rotation of the electric connection device 8 about axis Al .

In a preferred embodiment, the connector 23 is configured to rotate 360° about axis Al .

In addition, the connector 23 is configured to rotate about an axis parallel to the conductive elements 21 to allow an upward or downward movement of the electric cable 9, preferably perpendicularly to the ground S. The connector 23 comprises an angular measuring device 26 to measure the angular movement of the connector 23 about axis Al and about axis A2.

The slider 22 is supported by the conductive elements 21 and is free to move along the conductive elements 21. In particular, the slider 22 is drawn along the conductive elements 21 by the electric cable 9.

In an alternative embodiment of the present invention, the slider 22 comprises an active actuating device 24 configured to move the slider 22 along the conductive elements 21. In particular, the active actuating device 24 is configured to move the slider 22 along the conductive elements 21 to follow the electric connection device 8 of the tracked vehicle 2. The active actuating device 24 comprises a motor.

The power supply apparatus 3 comprises a position detector 27 configured to detect the position of the slider 22 along the path PI. The power supply apparatus 3 is connected to the control unit 16 to transmit and receive data. The power supply apparatus 3 sends the position of the slider to the control unit 16.

The slider 22 is connected to the control unit 16 to transmit and receive data. The slider 22 sends data regarding measurement of the rotation about axis Al and about axis A2 of the connector 23 to the control unit 16.

The slider 22 comprises a sliding contact 25, coupled to the conductive elements 21, to transmit electrical power. In an alternative embodiment of the present invention, the conductive elements 21 are configured to transmit electrical power and electrical signals.

The control unit 16 processes the data regarding the position of the slider 22 along the path PI, the angular movement of the connector 23 about axis Al and about axis A2 and the measurement of the length of unwound cable 9 and determines the position of the tracked vehicle 1 inside the work area P. In the case where the work area P is covered in snow, the control unit 16 comprises a storage unit 28 in which the work area P is memorized. The control unit 16 determines the height of the tracked vehicle 1 and, based on the memorized work area P, computes the amount of snow beneath the tracked vehicle 1. On the basis of the received data, the control unit 16 determines an optimal path for the tracked vehicle 2 to optimize consumption and to improve the work that the tracked vehicle 1 must carry out inside the work area P. The control unit 16 sends the data regarding the optimal path to the tracked vehicle 2. The tracked vehicle 2 comprises a graphical interface 29 that shows an operator the optimal path to follow inside the work area P.

In one embodiment, the electricity supply system 20 is supplied with direct current. The tracked vehicle 2 comprises a direct current electric machine and a voltage regulator to vary the speed and/or torque of the direct current electric machine. In an alternative embodiment, the tracked vehicle 2 comprises an alternating current electric machine and a converter that is connected to the electric machine and is configured to convert direct current into alternating current and vice versa.

In another embodiment of the present invention, the electricity supply system 20 is supplied with alternating current. The tracked vehicle 2 comprises a direct current electric machine and a converter connected to the electric machine and configured to convert alternating current into direct current and vice versa. In an alternative embodiment, the tracked vehicle 2 comprises an alternating current electric machine and two converters connected to the electric machine and configured to control the alternating current of the electricity supply system 20 and the alternating current of the electric machine. In an alternative embodiment of the present invention, not show in the accompanying drawings, the power supply apparatus does not comprise the sliding contact and the electric connection device comprises a sliding contact that couples to the conductor system of the power supply apparatus, for example a pantograph that couples to the conductor system of the power supply apparatus .

Furthermore, it is evident that the present invention also covers embodiments not described in the detailed description and equivalent embodiments that fall within scope of the appended claims.