Snow tiller

Abstract

A snow tiller (1) for preparing ski piste has a frame (2) configured to be coupled to a crawler vehicle (3) and advanced in a forward direction (D1); at least one rotor (4) rotatably supported around an axis of rotation (A1) by the frame (2); an electric motor (10) driving the rotor (4); and a plurality of linear actuators (12, 13, 14) of control, each of which is a DC electric actuator or a hydraulic actuator driven by a hydraulic pump (16) and a hydraulic circuit mounted on board the snow tiller (1), the hydraulic pump (16) being driven by an additional electric motor (15) mounted on board the snow tiller (1) or by the electric motor (10) driving the rotor (10).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims priority from Italian patent application no. 102024000024288 filed on October 30, 2024, the entire disclosure of which is incorporated herein by reference.FIELD OF THE ART

[0002] The present invention relates to a snow tiller used in the preparation of ski pistes.BACKGROUND OF THE INVENTION

[0003] Generally, a snow tiller has a frame configured to be coupled to a crawler vehicle, which has the function of advancing the snow tiller in a forward direction and feeding the snow tiller with the power necessary to drive the snow tiller; at least one rotor rotatably supported by the frame and provided with teeth configured to mill the snowpack; a rotor housing arranged around the rotor; a finisher arranged downstream of the rotor to level the milled snowpack; and side wings to prevent powdery snow from depositing upstream of the snow tiller in the forward direction.

[0004] The snow tiller has a plurality of actuators: at least one rotating actuator to drive the rotor and linear actuators to adjust the relative position between the rotor and the rotor housing and / or the relative position between the rotor and the rotor housing and the position of the side wings.

[0005] Examples of snow tillers are shown in documents EP 3, 755, 844 B1 and WO 2020 / 165, 799 A1 of the present Applicant.

[0006] In addition, a snow tiller can be equipped with additional equipment configured to make cross-country ski pistes with two or more tracks for alternating-pitch cross-country skiing. The additional equipment comprises at least one further rotor arranged downstream of the finisher and a tracer, which is arranged downstream of the further rotor and has shoes for imprinting the tracks in the snowpack as shown in patent EP 3,440,264 B1 of the present Applicant.

[0007] The additional equipment has at least one further rotary actuator to drive the rotor and further linear actuators to adjust the position of the further rotor and the tracer.

[0008] Generally, the rotary actuators are hydraulic motors and the linear actuators are hydraulic cylinders so the snow tiller is fed with flexible hoses adapted to contain the hydraulic liquid. Traditionally, the crawler vehicle is equipped with an internal combustion engine, which drives one or more hydraulic pumps to drive with hydraulic power the tracks, the snow tiller and other equipment associated with the crawler vehicle.

[0009] The energy transition imposes major changes in all areas of mobility. In particular, the land mobility sector has already been subject to strong changes dictated by the electrification of powertrains that is also extending to the crawler vehicles.

[0010] This paradigm shift requires finding efficient solutions also with regard to the tools associated with the crawler vehicle and the transfer of power from the crawler vehicle to the tools.OBJECT OF THE INVENTION

[0011] Aim of the present invention is to realize a snow tiller for preparing ski piste that interfaces efficiently to an electrified crawler vehicle.

[0012] In accordance with the present invention a snow tiller for preparing ski piste is realized, the snow tiller comprising: a frame configured to be coupled to a crawler vehicle and advanced in a forward direction; at least one rotor rotatably supported around an axis of rotation by the frame; at least one electric motor driving the rotor; a plurality of linear actuators of control, each of which is a DC electric actuator or a hydraulic actuator driven by a hydraulic pump and hydraulic circuit, the hydraulic pump being driven by an additional electric motor mounted on board the snow tiller or by the electric motor driving the rotor.

[0013] In this way, the power supply of the snow tiller involves transferring electrical power from the crawler vehicle and the connection of the snow tiller to the crawler vehicle is simplified.

[0014] The variant according to which the linear actuators are hydraulic actuators is easily achievable by virtue of the fact that the strokes of the linear actuators are relatively limited so that the hydraulic system can have small dimensions and easily be housed in the snow tiller.

[0015] In particular, the snow tiller comprises: a rotor housing arranged around the rotor; a finisher arranged downstream of the rotor in the forward direction and attached to the rotor housing so as to define a snow working chamber with the rotor; two side wings hinged to the frame at the opposite ends of the frame, said plurality of linear actuators of which includes: a first linear actuator to adjust the position of the rotor relative to the snowpack; a second linear actuator to adjust the relative position between the rotor housing and the rotor and / or the relative position between the rotor housing and the finisher; and two third linear actuators to adjust the position of the respective side wings.

[0016] In this way it is possible to adjust all the functions of the snow tiller that allow the snow tiller to be adapted to the different conditions of the snowpack in order to obtain high-quality snowpack working levels for any condition in which the snowpack is found. The snowpack conditions notoriously include powder snow, icy snow, transformed snow, and many conditions in between.

[0017] In a variant, the rotor of the snow tiller comprises two drums connected by a homokinetic joint and rotating around respective axes incident with and supported by two respective rotor housings mounted to the main frame so that the drums can adapt to the conformation of the snowpack transversely to the forward direction. The two drums are in fact articulated around the homokinetic joint.

[0018] The rotor is driven by means of the electric motor, which is connected to the homokinetic joint by means of a first mechanical transmission so as to drive both drums with a single electric motor.

[0019] According to a variant, the electric motor is connected to one end of one of the drums by means of a second mechanical transmission. Als this solution allows to rotate both drums with a single electric motor.

[0020] According to a further variant, the electric motor is connected to one end of both drums by means of a further mechanical transmission. In this case, the torque transmission is more balanced.

[0021] In accordance with another variant, the snow tiller comprises two electric motors, each of which is connected directly to the opposite ends of the drums. In this variant the homokinetic joint can be disconnected.

[0022] From a construction point of view, the electric motor and any additional electric motor are AC electric motors because they are reliable.

[0023] However, each electric motor and / or each additional electric motor is powered by direct current and includes a respective inverter to switch direct current to alternating current because direct current power distribution is preferable to alternating current distribution.

[0024] In particular, the snow tiller comprises at least one equipment of track tracing for preparing a cross-country ski piste, which equipment includes an additional rotor for milling the snowpack arranged downstream of the snow finisher; an additional electric motor to drive the additional rotor; a tracking device arranged downstream of the additional rotor; a fourth linear actuator to adjust the vertical position of the additional rotor; a fifth linear actuator to adjust the position of the further rotor in a direction transverse to the forward direction; and a sixth linear actuator to adjust the working depth of the tracking device, where the fourth, fifth, and sixth linear actuators are DC electric actuators or hydraulic actuators driven by the hydraulic pump and hydraulic circuit mounted on board the snow tiller.

[0025] In particular, the snow tiller comprises an electrical connector for connecting to an electrical connector of the crawler vehicle so as to transfer electrical power from the crawler vehicle to the snow tiller.

[0026] It is advantageous the fact that no hydraulic connections are necessary regardless of whether the linear actuators are electrically or hydraulically driven.

[0027] The electrical power on board the snow tiller is conveniently distributed via a DC power distribution BUS including at least one line of high voltage, specifically 700 volts to power the electric motor.

[0028] The distribution BUS 13 comprises a plurality of lines at low voltage to feed said linear actuators.BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further characteristics and advantages of the present invention will become clear from the following description of a non-limiting example of embodiment thereof, with reference to the figures of the attached drawings, wherein: Figures 1 and 2 are plan views, with parts removed for clarity, of a snow tiller coupled to a crawler vehicle in accordance with two alternative embodiments of the present invention; Figures 3 to 7 are rear elevational views, with parts removed for clarity, of variants of the present invention; Figure 8 is a view, with parts removed for clarity, of a diagram of electrical power distribution between the crawler vehicle and the snow tiller; and Figure 9 is a view, with parts removed for clarity, of a diagram of electrical power distribution between the crawler vehicle and the snow tiller. PREFERRED EMBODIMENT OF THE INVENTION

[0030] With reference to Figures 1 and 2, reference numeral 1 denotes a snow tiller, which comprises a frame 2 configured to be connected to a crawler vehicle 3 for advancing the snow tiller 1 in a forward direction D1.

[0031] The snow tiller 1 comprises a rotor 4, which is rotatably supported by the frame 2 around an axis of rotation A1; a rotor housing 5 arranged around the rotor 4; a finisher 6 arranged downstream of the rotor 4 relative to the forward direction D1 and attached to the rotor housing 5; and two side wings 7 configured to prevent powdery snow from depositing upstream of the snow tiller 1.

[0032] The confined space between the rotor 4, the rotor housing 5, and the finisher 6 is called the "snow working chamber" and the volume of the snow working chamber is an important parameter to provide high quality snow working.

[0033] The rotor 4 comprises a drum 8 and a plurality of teeth 9 distributed along the drum 8 for milling the snowpack.

[0034] The snow tiller 1 comprises an electric motor 10 driving the rotor 4 in rotation around the axis of rotation A1. In this case, the electric motor 10 is an AC motor, is powered by direct current at a voltage of 700 Volts, and comprises an inverter 11 for transforming direct current into alternating current.

[0035] The snow tiller 1 further comprises a plurality of linear actuators 12, 13, 14. In this case, the linear actuator 12 has the function of varying the working depth of the rotor 4; the actuator 13 has the function of varying the relative position between the rotor 4 and the rotor housing 5 in the same way as shown in EP 3, 775, 844 B1 to vary the volume of the snow working chamber; and the actuators 14 have the function of orienting the side wings 7 around respective articulation axes B1 and B2 thereof relative to the frame 2.

[0036] In an alternative embodiment, the actuator 13 has the function of varying the relative position between the finisher 6 and the rotor housing 5 in the same way as shown in WP 2020 / 165799 A1.

[0037] In accordance with a further alternative, the snow tiller has a plurality of actuators 13 to control both the relative position between the rotor housing 5 and the rotor 4, and the relative position between the rotor housing 5 and the finisher 6.

[0038] With reference to the embodiment of Figure 1, the linear actuators 12, 13 and 14 are electric actuators powered by direct current, in particular at a voltage of 24 Volts.

[0039] With reference to the embodiment of Figure 2, the electric motor 10 is an AC motor powered by direct current and provided with an inverter 11 as in the embodiment of Figure 1, while the linear actuators 12, 13 and 14 are hydraulic actuators. The snow tiller 1 comprises a hydraulic pump 15 and a hydraulic circuit comprising a tank 16 supported by the frame 2 so as to power and control the linear actuators 12, 13, and 14. The hydraulic pump 15 is driven by an AC electric motor 16, powered by direct current and provided with a respective inverter 17.

[0040] Figure 3 is a relative variant of the snow tiller 1 having a rotor 18, which comprises two drums 19 connected by a homokinetic joint 20 and rotating around respective axes A2 and A3 incident with and supported by the frame 2 so that the drums 19 can adapt to the conformation of the snowpack transversely to the forward direction D1. In practice, drums are articulated around an axis C1 parallel to the forward direction D1 (Figures 1 and 2). In this case, the drums 19 are rotatably supported around respective axes A2 and A3 by respective rotor housings 21, which also have the function of supporting frame and are articulated to the frame 2 around respective axes C2 and C3 parallel to the axis C1. The articulation around the axes C2 and C3 is made by means of rubber bushes R to allow lateral displacements of the rotor housings 21 with respect to the frame 2.

[0041] The drums 19 are provided with respective teeth not shown in Figure 3 and are rotated by a single AC electric motor 22, mounted on a rotor housing 21 and powered by alternating current and provided with an inverter 23, which is connected to the homokinetic joint 20 by means of a mechanical transmission 24.

[0042] In the variant of Figure 4, the drums 19 are driven by a single AC electric motor 22, mounted on one of the rotor housings 21, powered by direct current and provided with an inverter 23. The electric motor 22 is connected to the side end of a drum 19 by means of a mechanical transmission 25.

[0043] In the variant of Figure 5, the drums 19 are driven by a single AC electric motor 22, mounted on one of the rotor housings 21, powered by alternating current and provided with an inverter 23. The electric motor 22 is connected to the side ends of the drums 19 by means of a mechanical transmission 26.

[0044] In the variant of Figure 6, the drums 19 are driven by two AC electric motors 22, mounted on the rotor housings 21, powered by alternating current and provided with an inverter 23. The electric motors 22 are directly connected to the side ends of the drums 19.

[0045] With reference to Figure 7, the snow tiller 1 is associated with four equipments 27 of track tracing for preparing cross-country ski pistes. Each equipment 27 comprises a frame 28 connected to the frame 2; a rotor 29 for milling the snowpack and arranged downstream of the finisher 6; an additional electric motor 30 to rotate the further rotor 29; a tracking device 31 arranged downstream of the further rotor 29; a linear actuator 32 to adjust the vertical position of the milling rotor 29; a fifth linear actuator 33 to adjust the position of the rotor 29 in a direction transverse to the forward direction D1; and a linear actuator 34 to adjust the working depth of the tracking device 31.

[0046] Each electric motor 29 is a motor driven by alternating current and powered by direct current at 700 Volt, so it comprises an inverter not shown in the attached Figures.

[0047] The linear actuators 32, 33, and 34 are electric actuators driven by direct current or alternatively hydraulic actuators driven by the hydraulic pump and hydraulic circuit mounted on board the snow tiller 2 as shown in Figure 2.

[0048] With reference to Figure 8, the diagram shown refers to the configuration described with reference to Figure 1 and the first embodiment of the invention. In accordance with this diagram, the electrical power is transferred from the crawler vehicle 3 to the snow tiller 1 by means of two connectors 35 and 36 and is distributed on board the snow tiller 1 through a bus comprising a line 37 at high voltage, in particular 700 Volts, to feed the electric motor 10, and four lines 38 at low voltage, in particular 24 Volts, to feed the linear actuators 12, 13, 14. The crawler vehicle 3 comprises a control unit 39 connected to the lines 37 and 38 so as to manage the delivery of electrical power.

[0049] It is evident that the number of lines 37 and 38 varies depending on the configuration of the snow tiller 1 and the number of equipment 27 associated with it.

[0050] With reference to Figure 9, the diagram shown refers to the configuration described with reference to Figure 2 and the second embodiment of the invention.

[0051] In this case the lines 38 at low voltage are omitted and there are only lines 37 at high voltage to feed the electric motors 10 and 16.

[0052] The pump 15 feeds the fluid to the actuators 13, 14 and 15 circulates the fluid in a hydraulic circuit comprising a collection tank 40. The hydraulic circuit is fully mounted on the snow tiller 1.

[0053] It is evident that the number of lines 37 varies as a function of the configuration of the snow tiller 1 while the hydraulic circuit varies as a function of the number of equipment 27 associated with it.

[0054] It is clear that the present invention is also applicable in variants not expressly described and falling within the scope of protection of the appended claims.

[0055] Further, the snow tiller may comprise more than two articulated shafts.

Claims

1. A snow tiller for preparing ski piste the snow tiller comprising: - a frame (2) configured to be coupled to a crawler vehicle (3) and advanced in a forward direction (D1); - at least one rotor (4; 18) rotatably supported around an axis of rotation (A1; A2, A3) by the frame (2); - an electric motor (10; 22) driving the rotor (4); - a plurality of linear actuators (12, 13, 14) of control, each of which is a DC electric actuator or a hydraulic actuator driven by a hydraulic pump (16) and hydraulic circuit mounted on board the snow tiller (1), the hydraulic pump (16) being driven by an additional electric motor (15) mounted on board the snow tiller (1) or by the electric motor (10; 22)) driving the rotor (4; 18).

2. The snow tiller as claimed in claim 1 and comprising: - a rotor housing (5, 21) arranged around the rotor (4; 18); - a finisher (6) arranged downstream of the rotor (4; 18) in the forward direction (D1) and attached to the rotor housing (5; 21) to define a snow working chamber with the rotor (4; 18); - two side wings (7) hinged to the frame (2) at the opposite ends of the frame (2), the said plurality of linear actuators (12, 13, 14) of which includes: - a first linear actuator (12) to adjust the position of the rotor (5; 18)) relative to the snowpack; - at least one second linear actuator (13) to adjust the relative position between the rotor housing (5; 12) and the rotor (4; 18) and / or the relative position between the rotor housing (5; 12) and the finisher (6); and - two third linear actuators (14) to adjust the position of the respective side wings (7).

3. The snow tiller as claimed in claim 1 or 2, in which the rotor (18) comprises two drums (19) connected by a homokinetic joint (20) and rotating around respective axes (A2, A3) coincident with and supported by two respective rotor housing (21) mounted to the main frame (2) so that the drums (19) can adapt to the conformation of the snowpack transversely to the forward direction (D1).

4. The snow tiller as claimed in claim 3, wherein said electric motor (22) is connected to said homokinetic joint (20) by means of a first mechanical transmission (24).

5. The snow tiller as claimed in claim 3, in which said electric motor (22) is connected to one end of one of the drums (19) by means of a second mechanical transmission (25).

6. The snow tiller as claimed in claim 3, in which said electric motor (22) is connected to one end of both drums (19) by means of an additional mechanical transmission (26).

7. The snow tiller as claimed in claim 3 and comprising two electric motors (22), each of which is connected directly to the opposite ends of the drums (19).

8. The snow tiller as claimed in any of the preceding claims, wherein said electric motor (10; 22) and any additional electric motor (15) are AC electric motors.

9. The snow tiller as claimed in claim 8, in which each electric motor (19; 22) and / or each additional electric motor (16) includes a respective inverter (11; 23) to switch hightension direct current to alternating current.

10. The snow tiller as claimed in any one of the preceding claims, and comprising at least one equipment (27) of track tracing for preparing a cross-country ski piste, which includes an additional rotor (29) for milling the snowpack arranged downstream of the snow finisher (6); an additional electric motor (30) to drive the additional rotor (29); a tracking device (31) arranged downstream of the additional rotor (29); a fourth linear actuator (32) to adjust the vertical position of the additional rotor (29); a fifth linear actuator (33) to adjust the position of the further rotor (29) in a direction transverse to the forward direction (D1); and a sixth linear actuator (34) to adjust the working depth of the tracking device (31), where the fourth, fifth, and sixth linear actuators (32, 33, 34) are DC electric actuators or hydraulic actuators driven by the hydraulic pump (16) and hydraulic circuit mounted on board the snow tiller (1).

11. The snow tiller as claimed in any one of the preceding claims and comprising and electrical connector (36) for connecting to an electrical connector (35) of the crawler vehicle (1) so as to transfer electrical power from the crawler vehicle (3) to the snow tiller (1).

12. The snow tiller as claimed in any of the preceding claims and comprising a DC power distribution BUS including at least one line (37) of high voltage, specifically 700 volts to power said electric motor (10; 22; 15).

13. The snow tiller as claimed in claim 12 and comprising a plurality of lines (38) at low voltage to feed said linear actuators (12, 13, 14; 12, 13, 14, 32, 33, 34).

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