EP-4739843-A1 - RAIL FOR MAGNETIC LEVITATION VEHICLE

EP4739843A1EP 4739843 A1EP4739843 A1EP 4739843A1EP-4739843-A1

Abstract

A rail (20) is described to guide a vehicle along an axis, The rail (20) comprises a body elongated parallel to the axis and consisting of a rigid first material, and a layer (28), applied on the first material, of a second material that is different from the first material, has lower hardness than the first material, and has higher adhesion or coefficient of friction than the first material, and extends parallel to the axis so as to form a track for a rolling element to roll on it.

Inventors

GIROTTO, ADRIANO
CESARETTI, Luca
PARROTTA, Lorenzo Andrea

Assignees

Ironbox S.r.L.

Dates

Publication Date: 20260513
Application Date: 20240701

Claims (10)

1 . Rail to guide a vehicle along an axis, comprising: a body elongated parallel to the axis and consisting of a rigid first material, and a layer, applied on the first material, of a second material that - is different from the first material, - has lower hardness than the first material, - has higher adhesion or coefficient of friction than the first material, and the layer extends parallel to the axis so as to form a track for a rolling element to roll on it.
2. Rail according to claim 1 , wherein the second material is rubber or a polymeric material.
3. Rail according to claim 1 or 2, wherein the layer is placed on an outer, - in usevertical surface of the rail, or the rail comprises two opposite sides that each define an outer surface of the rail, on at least one of such outer surfaces being applied said layer.
4. Rail according to any one of the preceding claims, wherein the second material contains internally a reinforcing member made of a third material and in the form of a core, strand, fiber, lattice, or net, the third material being different from the second material.
5. Rail according to any one of the previous claims, having an inverted T-shaped cross-section and comprising: a base for support on the ground, a first stem that in use extends vertically from the base and orthogonally to the base, and ends with an enlarged mushroom-shaped member, said layer being placed on an outer vertical surface of the stem.
6. Rail according to any of claims 1 to 4, having an inverted T-shaped cross-section and comprising: a base for support on the ground, a stem that in use extends vertically from the base and orthogonally to the base, and ends with an enlarged mushroom-shaped member comprising a central body that in use extends parallel to the stem, and two enlargements of the central body that expand in use horizontally from the central body, the two enlargements each having two opposite ends that protrude from the central body each resulting in two polar expansions of the mushroomshaped member, said layer being applied on at least one surface of the central body between two of said polar expansions that are on the same side of the central body.
7. Rail according to any one of the preceding claims, wherein the mushroomshaped member comprises an upwardly facing outer surface, in such surface being mounted or integrated in cantilevered manner a rolling portion made of material different from that of the mushroom-shaped member, which material is more resistant to vertical pressure exerted by a wheel.
8. Assembly comprising: • a rail as defined in any one of the preceding claims and comprising a portion reactive to a magnetic field, and • a magnetic levitation skid to move a vehicle on the rail parallel to said axis, comprising: - a magnetic circuit adapted to generate a magnetic field that interacts with said reactive portion in order to develop a force adapted to support the skid relative to the rail, and - a rolling element, e.g. having a vertical rotation axis, adapted to roll on said track as the skid moves along the rail.
9. An assembly according to claim 8, wherein the skid comprises a braking member adapted to contact, e.g. to slide with friction on, said layer in a controllable manner in order to brake the skid relative to the rail.
10. Assembly according to claim 8 or 9, wherein the skid comprises means for separating or distancing the magnetic circuit of the skid from said reactive portion of the rail. * * *

Description

Rail for magnetic levitation vehicle The invention relates to a rail for a magnetic levitation vehicle, an assembly of magnetic levitation skid and such rail, and the vehicle equipped with the assembly. Magnetic levitation vehicles for mass transport, such as trains (taken here as an example), are known, e.g. from WO2017216656. These vehicles however need wheels anyway, e.g. during movement at low speed near stations or especially in the magnetic levitation skids for centering the skid on the rail. As cruising speeds increase, several problems arise for the centering wheels. Metal centering wheels over-heat and wear out a lot when rolling on the rail. Rubber centering wheels, already known to be used to reduce travel noise, would deteriorate very quickly due to the high cycling. The main object of the invention, defined in the attached claims in which the dependent claims define advantageous variants, is to improve this state of the art. A particular object is to create an improved rail for the coupling to a magnetic levitation skid. Another particular object is to create an improved assembly of rail and magnetic levitation skid. Another particular object is to be able to effectively carry out coupling/uncoupling operations between the skid and the rail. A first aspect of the invention concerns a rail for guiding a vehicle along an axis, the rail comprising: a body elongated parallel to the axis and consisting of a rigid first material (e.g. steel or iron), and a layer of a second material applied on the first material, wherein the second material is different from the first material, and the layer extends parallel to the axis so as to form a (preferably flat) surface or track for the rolling of a rolling member thereon. This solution avoids the aforementioned drawbacks for metal and rubber wheels: metal wheels overheat and wear a lot while rolling on the rail, while rubber wheels, already known to be used to reduce travel noise, would deteriorate a lot quickly due to the high cycle time. Instead, said layer on the rail has very low cycling (i.e. it is stressed only when the vehicle transits), ergo it is long-lasting, has low overheating and guarantees silent transit of the skid. Said layer forms a rolling surface for the rolling member, and the rolling surface may in use lie in a vertical, horizontal or oblique plane. In a preferred embodiment, said layer is placed on an external (vertical) surface of the rail. In particular, the rail comprises two opposite sides which each define an external, preferably flat, surface of the rail, on at least one said external flat surfaces being applied said layer. In a preferred embodiment, the rail has a mushroom or inverted T-shaped crosssection and comprises: a base (e.g. flat) for resting on the ground, a first stem which (in use) extends vertically from the base and orthogonally to the base, and which ends with an enlarged mushroom-shaped portion. In a more preferred embodiment, the rail comprises a second stem that extends from the mushroom portion coplanar to the first stem and in a direction opposite to the first stem. In a preferred embodiment, said layer is placed on an external (vertical) surface of the first and/or second stem. In particular, the first and/or second stems comprise two opposite sides which each define an external (preferably flat) surface of the stem, said layer being applied on at least one said flat external surfaces. In a preferred embodiment, said layer is placed on the mushroom portion. In particular, the mushroom portion defines an external upper (preferably flat and/or vertical in use) surface of the rail on which said layer is applied. More specifically, said layer forms a cap that covers the mushroom portion, in order to create a sliding track for a wheel. In a more preferred embodiment, said mushroom portion is made of ferromagnetic material, to convey magnetic flux. In a more preferred embodiment, said mushroom portion is covered by a layer of high magnetic permeability and low conductivity material, e.g. laminations or Somaloy. To increase the functionality of the mushroom portion, in a preferred embodiment on the upwards-facing external surface of the mushroom portion there is mounted or integrated in a cantilevered manner a rolling portion made of material different from that of the mushroom portion, in particular a material more resistant to the exerted vertical pressure, such as steel or iron. The rolling portion is preferably a track or a bar or a rail or an ingot. To increase the load limit of the skid, and with the advantage of reducing eddy currents, in an even more preferred embodiment, said mushroom portion has an H- shaped cross-section or comprises: a central body which (in use) extends parallel to the stem, and two enlargements of the central body which expand (in use) horizontally from the central body, the two enlargements each having two opposite ends which protrude from the central body each determining two pol