Patent Description:
The present invention relates to a system to simulate the work conditions of the connection cables between two following cars of a railway rake.

As known, a railway rake is provided with a plurality of cars (typically comprising a locomotive and a control car) which are connected to one another also by a cabling system.

The cabling system comprises in turn a plurality of fixed cables housed on the cars and a plurality of cables designed to provide the connection between two following cars by the coupling of a plurality of connectors and counter-connectors. Typically, the connection cables are suspended between two following cars. When in use, the cars are subjected to significant both mechanical and thermal stresses and to different types of reciprocal motion which depend, for example, on the type of operation in progress (including running on a straight track, entering a corner, and manoeuvres carried out in the yard); consequently, also the suspended cables designed to provide the connection between two following cars are subjected to repeated thermal and mechanical stresses (in particular due to bending and torsion). A system to simulate the work condition of the connection cables between two following cars of a railway rake is known from <CIT>.

For the purposes of safety, it is therefore of fundamental importance to be able to simulate the work conditions of the connection cables of two following cars and, in particular, reproduce the stresses to which they are subjected during the ordinary operations of a railway rake.

For this purpose, a simulation system has been proposed designed to reproduce the mechanical stresses to which the connection cables are subjected which comprises a frame having a first rod, at a first upper end of which a first connector-holder element is connected for a first pair of connectors and/or counter-connectors, and a second rod, at an upper end of which a second connector-holder element is connected for a second pair of connectors and/or counter-connectors which are arranged, during the simulation, facing the first pair of connectors and/or counter-connectors.

In a set-up and adjusting phase prior to the actual simulation phase, the two connector-holder elements are arranged at a certain distance from each other so as to simulate the distance between two following cars of a given model of railway rake.

During the actual simulation phase, on the other hand, the two connector-holder elements move in two directions substantially orthogonal to each other by means of respective drives, preferably of pneumatic type.

<CIT> describes a simulation system that simulates the work conditions of the connection cables between two following cars of known type.

However, the simulation systems of known type have some drawbacks, in particular they are not able to replicate all the mechanical and thermal stresses to which the connection cables are subjected in normal work conditions.

The object of the present invention is therefore to provide a simulation system to simulate the work conditions of the connection cables between two following cars of a railway rake, which is free from the drawbacks described above, allows replication of all the mechanical and thermal stresses to which the connection cables are subjected in normal work conditions and, in particular, is easy and inexpensive to produce.

According to the present invention a simulation system is provided to simulate the work conditions of the connection cables between two following cars of a railway rake as claimed in the attached claims.

The present invention will now be described with reference to the attached drawings, which illustrate a non-limiting embodiment example thereof, in which:.

In <FIG>, the number <NUM> indicates overall a railway rake <NUM> having a plurality of cars <NUM> (typically comprising at least one locomotive <NUM> and a control car) which are connected to one another also by means of a cabling system <NUM>.

The cabling system <NUM> comprises in turn a plurality of fixed cables <NUM> housed on the cars <NUM> and a plurality of cables <NUM> designed to provide the connection between two following cars <NUM>, <NUM> via the coupling of a plurality of connectors <NUM> and counter-connectors. Typically, the connection cables <NUM> are suspended between two following cars <NUM>, <NUM>.

In <FIG>, the number <NUM> indicates overall a simulation system designed to reproduce the mechanical and thermal stresses to which the connection cables <NUM> are subjected in work conditions.

The simulation system <NUM> comprises a test structure <NUM> having a supporting frame <NUM> for a fixed assembly <NUM> and a movable assembly <NUM>.

According to a preferred variation, the test structure <NUM> (namely both the fixed assembly <NUM> and the movable assembly <NUM>) is housed in a climatic chamber (not illustrated) designed to keep the operating temperature constant at a value comprised between - <NUM> and +<NUM>.

The movable assembly <NUM> is made to simulate/reproduce the axial movements to which the connection cables <NUM> are subjected in work conditions; while the fixed assembly <NUM> is designed to simulate/reproduce the rotations to which the connection cables <NUM> are subjected in work conditions.

In further detail, the movable assembly <NUM> comprises an inverted delta robot <NUM>. The delta robot <NUM> comprises a fixed base <NUM> connected to the supporting frame <NUM> and a movable platform <NUM>, which is connected to the fixed base <NUM> by means of three connection arms <NUM>. Each connection arm <NUM> is provided by means of a crank <NUM> connected to a respective articulated parallelogram <NUM>.

The movable platform <NUM> is designed so as to perform movements while always remaining parallel to the fixed base <NUM>. In other words, the movable platform <NUM> is able to translate along the three axes X, Y and Z, but it is not able to rotate around the above-mentioned axes X, Y and Z.

The movable platform <NUM> places itself, in use, at a maximum distance from the fixed base <NUM> comprised between +<NUM> and +<NUM> (calculated relative to the plane defined by the fixed base <NUM>); preferably, the movable platform <NUM> places itself, in use, at a maximum distance of +<NUM> from the fixed base <NUM>.

The delta robot <NUM> is made so as to allow the movable platform <NUM> at least the following movements:.

The work space in which the delta robot <NUM> moves (and in particular the movable platform <NUM>) is defined by a plurality of substantially concentric surfaces, the size of which decreases as the distance from the fixed base <NUM> increases. In particular, the surfaces covered by the movable platform <NUM> are substantially concentric trianguloids gradually increasing in size as they get nearer the fixed base <NUM>. If the shifts along the axis Z are below +<NUM>, the surfaces covered by the movable platform <NUM> take substantially the form of three-pointed stars gradually decreasing in size as they get nearer the fixed base <NUM>.

During the actual simulation phase, the platform <NUM> can move within a volume defined by the plurality of substantially concentric surfaces, the size of which decreases as the distance from the fixed base <NUM> increases.

Furthermore, the delta robot <NUM> comprises a number of actuator devices <NUM> for driving the movements of the connection arms <NUM>. In particular, the delta robot <NUM> comprises an actuator device <NUM> for each connection arm <NUM> comprising in turn an operating motor <NUM>, preferably of brushless type, each of which is connected to a respective crank <NUM>, preferably with the interposition of a respective reduction gear <NUM>. According to a preferred embodiment, braking devices are provided (not illustrated) for locking the cranks <NUM> in the absence of power from the respective operating motors <NUM>. The operating motors <NUM> and the respective reduction gears <NUM> are housed on the fixed base <NUM>.

To the movable platform <NUM> is rigidly connected a supporting element <NUM> defined by at least a bracket <NUM> to which a connector-holder plate <NUM> is connected, on a surface of the latter, facing the fixed assembly <NUM>, a number of connectors <NUM> and/or counter-connectors are arranged.

According to a preferred variation, up to four connectors <NUM> and/or counter-connectors are arranged on the connector-holder plate. According to a preferred embodiment, supports are provided for the connectors <NUM> and/or counter-connectors connected to the connector-holder plate <NUM> and interchangeable so as to adapt to different types of connectors <NUM> and/or counter-connectors.

The supporting frame <NUM> comprises a telescopic structure <NUM> to allow sliding of the fixed assembly <NUM> relative to the movable assembly <NUM>. In a set-up and adjusting phase preliminary to the actual simulation phase, the fixed assembly <NUM> is made to slide along the axis X until it places itself at a given distance from the movable assembly <NUM> so as to simulate the desired distance between two following cars <NUM> of a given model of railway rake <NUM>. In other words, it is possible to move the fixed assembly <NUM> closer to/away from the movable assembly <NUM> to arrange them at the desired distance and so as to replicate the distance between two following cars <NUM> of a given model of railway rake <NUM>.

According to an embodiment not illustrated, the telescopic structure <NUM> allows sliding of the fixed assembly <NUM> also along the Y axis.

According to an embodiment not illustrated, the supporting frame <NUM> comprises a track orthogonal to the telescopic structure <NUM> on which the fixed assembly <NUM> is free to slide. The two linear guides are connected, at the ends thereof, to two head elements, designed to act as stroke ends for the fixed assembly <NUM>.

In a set-up and adjusting phase preliminary to the simulation phase, the fixed assembly <NUM> slides along the tracks along the axis Y as far as a predefined given position so as to simulate a possible misalignment in installation of the connectors <NUM> and/or counter-connectors between two following cars <NUM> of a given model of railway rake <NUM>. Members (not illustrated) are also provided to lock the fixed assembly <NUM> in the desired position.

The fixed assembly <NUM> comprises a rod <NUM> at an upper end of which a supporting element <NUM> is connected defined by a connector-holder plate <NUM> facing the movable assembly <NUM> and on a surface of which a number of connectors <NUM> and/or counter-connectors are arranged. According to a preferred variation, up to four connectors <NUM> and/or counter-connectors are arranged on the connector-holder plate <NUM>. Clearly, on the connector-holder plate <NUM> the same number of connectors <NUM> and/or counter-connectors are arranged as on the connector-holder plate <NUM>.

During the simulation phase, the connectors <NUM> and/or counter-connectors face the connectors <NUM> and/or counter-connectors and are connected to one another by means of the respective connection cables <NUM> to be tested. The supporting element <NUM> is movable along the axis Z. In other words, the supporting element <NUM> is free to slide along the rod <NUM>.

In a set-up and adjusting phase preliminary to the actual simulation phase, the supporting element <NUM> is made to slide along the axis Z until it is arranged at a given distance from the ground so as to simulate the desired height for the connection cables <NUM> to be tested. The fixed assembly <NUM> comprises a member (not illustrated) designed to lock the supporting element <NUM> at the desired height.

The fixed assembly <NUM> comprises an actuator device <NUM> defined by an operating motor <NUM>, preferably of brushless type, connected to the connector-holder plate <NUM>, preferably with the interposition of a respective reduction gear <NUM>. According to a preferred embodiment, braking devices (not illustrated) are provided to lock the connector-holder plate <NUM> in the absence of power from the operating motor <NUM>. The operating motor <NUM> is designed to impart to the connector-holder plate <NUM> a rotation around the axis Z. In particular, the connector-holder plate <NUM> can cover around the axis Z angles γ having amplitude comprised between -<NUM>° and +<NUM>°.

The operating motor <NUM> is connected to a drilled "protractor" plate <NUM> rotating around the axis X. In particular, the plate <NUM> is made so as to define with the axis X an angle β having amplitude comprised between <NUM>° and +<NUM>°.

According to a preferred variation, in a set-up and adjusting phase preliminary to the actual simulation phase, an initial angle βi is defined and the plate <NUM> (and, consequently, the operating motor <NUM>) is locked by means of a locking device (not illustrated) in the position that allows said initial angle βi to be defined.

Furthermore, according to a first variation, the fixed assembly comprises a joint member (not illustrated) that allows rotation of the connector-holder plate <NUM> around an axis Y. In particular, the connector-holder plate <NUM> defines with the axis Y an angle α having amplitude comprised between <NUM>° and +<NUM>°.

According to a preferred variation, in a set-up and adjusting phase preliminary to the simulation phase, an initial angle α is defined and the connector-holder plate <NUM> is locked by means of a locking device (not illustrated) in the position that allows said initial angle α to be defined.

According to a further variation, the fixed assembly comprises sheet-like shims (not illustrated) interposed between the rod <NUM> and the plate <NUM> which allow rotation of the connector-holder plate <NUM> around an axis Y. In further detail, the sheet-like shims have a non-uniform thickness; in other words, the sheet-like shims have a substantially V-shaped form. The connector-holder plate <NUM> defines with the axis Y an angle αi having amplitude comprised between <NUM>° and +<NUM>°. In further detail, in a set-up and adjusting phase preliminary to the simulation phase, an initial angle α is defined and the connector-holder plate <NUM> is locked by means of the sheet-like shims in the position that allows said initial angle α to be defined.

During the actual simulation phase, the actual angle covered by the connector-holder plate <NUM> is represented by the trigonometric composition of the three angles αi, βi, γ.

The simulation system <NUM> further comprises a control unit which, for each simulation, is adapted to define the trajectory of the movable plate <NUM> in the work volume, adjust the speed of the movements (expressed in terms of work cycles per minute), establish the amplitude of the initial angle α and the initial angle β in which to lock the fixed assembly <NUM> and establish the amplitude of the angle γ covered during the actual simulation phase. Furthermore, according to a preferred variation, it is possible to save in a memory of the control unit different test sequences repeatable over time.

Claim 1:
A system (<NUM>) to simulate the work condition of the connection cables (<NUM>) between two following cars (<NUM>, <NUM>) of a railway rake (<NUM>) comprising a first assembly (<NUM>) and a second assembly (<NUM>), characterised in that:
- the first assembly (<NUM>) is designed to reproduce the axial movements to which the connection cables (<NUM>) are subjected in use and comprises, in turn:
- a delta robot (<NUM>) having a fixed base (<NUM>) and a movable platform (<NUM>), which makes translations along three axes (X, Y, Z) orthogonal to one another and is connected to the fixed base (<NUM>) by means of three arms (<NUM>); and
- a first support element (<NUM>), which is rigidly connected to the movable platform (<NUM>) and has a first connector-holder plate (<NUM>), which carries, on a surface of its, a number of first connectors (<NUM>) and/or counter-connectors; and
- the second assembly (<NUM>) is designed to reproduce the rotations to which the connection cables (<NUM>) are subjected in use and comprises a rod (<NUM>) connected, at an upper end of its, to a second support element (<NUM>) having a second connector-holder plate (<NUM>), which carries, on a surface of its, a number of second connectors (<NUM>) and/or counter-connectors facing, during the simulation phase, the first connectors (<NUM>) and/or counter-connectors; and wherein the second connector-holder plate (<NUM>) can rotate around the three orthogonal axes (X, Y, Z) .