阅读说明：本技术 用于捕获轨道车辆的电流的装置 (Device for capturing the current of a rail vehicle ) 是由 弗洛朗·卡诺勒 奥利维尔·多斯达 于 2019-07-26 设计创作，主要内容包括：本发明提供了一种用于捕获用于轨道车辆的电流的装置,包括旨在与电源轨道接触的垫、框架以及将框架机械地和电气地连接到垫的导电的臂。该装置包括用于测量施加到臂上的机械力的测试设备。该测试设备包括与臂接触并且集成在电隔离结构内的应变传感器(56),从而所述应变传感器与臂电隔离。隔离结构包括粘合层(52)和覆盖粘合层的陶瓷层(54)。所述应变传感器布置在陶瓷层上。(The invention provides a device for capturing electrical current for a rail vehicle, comprising a pad intended to be in contact with a power supply rail, a frame and an electrically conductive arm mechanically and electrically connecting the frame to the pad. The apparatus includes a test device for measuring mechanical forces applied to the arm. The test apparatus includes a strain sensor (56) in contact with the arm and integrated within the electrically isolated structure such that the strain sensor is electrically isolated from the arm. The isolation structure includes an adhesion layer (52) and a ceramic layer (54) overlying the adhesion layer. The strain sensor is disposed on the ceramic layer.)

1. A device (2) for capturing the current of a rail vehicle, the capturing device comprising:

-a pad (6) for contacting a power supply rail;

-a frame (8);

-an electrically conductive arm (4), said arm (4) mechanically and electrically connecting said frame (8) to said pad (6), said arm comprising a central portion (12) coupling said frame to a supporting portion (14), said pad (6) being mounted on said supporting portion (14); it is characterized in that the preparation method is characterized in that,

the capturing device (2) comprises a measuring device (40) for measuring a mechanical force exerted on the arm (4), the measuring device comprising a strain sensor (56) integrated inside an electrically isolating structure, such that the strain sensor is electrically isolated from the arm, the isolating structure comprising a bonding layer (52) deposited on a receiving surface (26; 28; 86) and a ceramic layer (54) covering the bonding layer, the strain sensor being arranged on the ceramic layer.

2. The apparatus according to claim 1, characterized in that the measuring device (40) is mounted on the upper surface (26) of the central portion of the arm.

3. The device according to claim 1, characterized in that the measuring device (40) is mounted on a side face (28) of the central portion of the arm.

4. A device according to claim 2 or 3, characterized in that the measuring device comprises two sets of strain sensors (56), each set being associated with a measuring circuit, the two sets being mounted on the same face of the central portion and being placed at different distances from the frame.

5. The device according to claim 1, wherein the frame (8) comprises an arm support (36), wherein the central portion (12) of the arm (4) comprises a hole (38) for receiving a dowel pin mounted on the arm support (36), and wherein the arm (4) further comprises a washer (80), the washer (80) being at least partially received in the hole (38) while being mounted around the dowel pin and compressed between the central portion (12) of the arm and the arm support (36) such that the arm (4) rests on the arm support (36) through the washer (80), the measuring device being mounted on an outer receiving surface (86) of the washer.

6. The apparatus according to any one of the preceding claims, wherein the measuring apparatus further comprises a temperature sensor (58) placed in the vicinity of at least one strain sensor.

7. Device according to any one of the preceding claims, characterized in that the isolating structure further comprises an encapsulation layer (60) made of resin or varnish covering the strain sensor (56).

8. Device according to any one of the preceding claims, characterized in that the thickness (e52) of the adhesive layer (52) is between 10 μm and 1 mm.

9. Device according to any one of the preceding claims, characterized in that the thickness (e54) of the ceramic layer (54) is between 0.05mm and 3 mm.

10. A current capture system (100) for a rail vehicle (102), characterized in that the system (100) comprises a capture device (2) for capturing current according to any one of claims 1 to 9 and a processing unit (104), the processing unit (104) being connected to a measuring device (40) and programmed to detect a break of an arm (4) and/or to calculate a contact force between a pad (6) and a power supply rail from strain measurements from the measuring device (40).

Technical Field

The invention relates to a device for capturing current for rail vehicles. The invention also relates to a rail vehicle comprising such a catching device.

Background

It is known that rail vehicles with electric traction are adapted to be supplied with electricity by external power supply means, such as a third rail extending along the track on which the vehicle is running. Such vehicles typically include a capture device for collecting current from the power supply rail.

The capture device includes a pad in contact with the track and connected to the frame by an arm. Typically, the arms are electrically conductive and are capable of transmitting the current drawn by the pad.

One disadvantage of these catch means is that the arms may deform (or break) when the vehicle is travelling, for example due to a collision with an obstacle on the track. When the arm is electrically conductive, such deformation (or breakage) may lead to the risk of short-circuiting or derailment if the vehicle is not parked in time.

Therefore, there is a need for a current capture device for a rail vehicle that overcomes these disadvantages.

Disclosure of Invention

To this end, the invention relates to a capturing device for an electric current of a rail vehicle, comprising:

-a pad intended to be in contact with a power supply rail;

-a frame;

an electrically conductive arm mechanically and electrically connecting the frame to the pad, the arm comprising a central portion coupling the frame to a support portion on which the pad is mounted.

The capturing device comprises a device for measuring mechanical forces exerted on the arm, the measuring device comprising a strain sensor integrated inside an electrically isolating structure, whereby said strain sensor can be electrically isolated from the arm, the isolating structure comprising an adhesive layer deposited on the receiving surface and a ceramic layer covering the adhesive layer, the strain sensor being arranged on the ceramic layer.

The measuring device allows real-time measurement of the mechanical forces experienced by the arm. The isolation structure allows the strain sensor to be electrically isolated from the arm.

Since the sensor is placed as close as possible to the arm, the measuring device allows reliable measurements without increasing the risk of leakage of the collected current from the arm to the measuring device.

The isolation structure avoids the use of galvanic isolation circuits (un) which is advantageous because adding such galvanic isolation circuits increases the cost and complexity of the trapping device.

According to an advantageous but optional aspect of the invention, the capturing device may incorporate one or more of the following features, considered alone or according to any technically allowable combination:

the measuring device is mounted on the upper surface of the central portion of the arm.

The measuring device is mounted on the side of the central part of the arm.

The measuring device comprises two sets of strain sensors, each set of sensors being associated with a measuring circuit, the two sets of sensors being mounted on the same face of the central portion and at different distances from the frame.

The frame comprises an arm support, the central portion of the arm comprising a hole for receiving a dowel pin mounted on the arm support, the arm further comprising a washer at least partially received in the hole while mounted around the dowel pin and compressed between the central portion of the arm and the arm support, such that the arm rests on the arm support through the washer, the measuring device being mounted on an outer receiving surface of the washer.

The measuring device further comprises a temperature sensor placed in the vicinity of the at least one strain sensor.

The isolation structure further comprises an encapsulation layer made of resin or varnish covering the strain sensor.

-the thickness of the adhesive layer is between 10 μm and 1 mm.

-the thickness of the ceramic layer is between 0.05mm and 3 mm.

According to another aspect, the invention relates to a current capture system for a rail vehicle, characterized in that it comprises a device for capturing current as described previously and a processing unit connected to the measuring device and programmed to detect the breakage of the arm and/or to calculate the contact force between the pad and the power supply rail from the strain measurements from the measuring device.

Drawings

The invention will be better understood and other advantages thereof will be clearer from the following description of an embodiment of a device for capturing electric current, given purely by way of non-limiting example and made with reference to the accompanying drawings, in which:

fig. 1 schematically shows a device for capturing the current of a rail vehicle according to an embodiment of the invention.

Fig. 2 schematically shows a part of the arrangement for capturing current in fig. 1 according to a first embodiment of the invention;

fig. 3 schematically shows a part of the arrangement for capturing current in fig. 1 according to a second embodiment of the invention;

figure 4 schematically shows a cross-sectional view of a measuring device equipped with the apparatus for capturing electrical current of figure 1;

fig. 5 schematically shows a part of the arrangement for capturing current in fig. 1 according to a third embodiment of the invention;

figure 6 schematically shows a bottom view of a part of the capturing device in figure 2;

fig. 7 is a block diagram of a meter system mounted on a rail vehicle and comprising the device for capturing current of fig. 1.

Detailed Description

Fig. 1 shows a device 2 for capturing the current of a rail vehicle. The device 2 can cooperate with a power rail to collect current from the power rail. The device 2 may then deliver the collected current to a power circuit on the rail vehicle, for example to power an electric traction chain of the rail vehicle.

According to an example, the power track is a third track located along a rail on which the rail vehicle is traveling.

As shown in fig. 1 and 2, the device 2 comprises an arm 4, a collected mat 6 and a frame 8, the frame 8 forming a support for the arm 4.

The pad 6 is intended to be in direct contact with the power supply rail to draw current from the power supply rail when the power supply rail is powered.

The pad 6 is made of an electrically conductive material, preferably carbon or a carbonaceous material.

In the example shown, the mat 6 is in the form of an elongated plate, the base of which is quadrangular, although in a variant the geometry of the mat 6 may also be adjusted based on the arrangement of the power tracks.

The arm 4 mechanically and electrically couples the pad 6 to the frame 8. Preferably, the arms 4 are rigid.

The arm 4 is made of an electrically conductive material, such as a metal, for example copper or aluminum or a metal alloy (for example copper aluminum alloy, or cast iron, or a carbonaceous alloy). The arm 4 can carry the current collected by the pad 6.

Fig. 2 shows an example of the arm 4 in an isometric perspective top view.

According to an embodiment, the arm 4 comprises a central body portion 12 and a support portion 14 of the pad 6.

For example, the body portion 12 or central portion comprises a substantially rectilinear rod, here having a rectangular cross-section.

In particular, the body portion 12 has an upper surface 26, a lower surface, and a side surface 28. For example, when the device 2 is in the installed state, the surface 26 is horizontal and the side 28 is vertical.

In a variant, the central portion 12 may have a different shape. For example, the rod may have a circular cross-section or a trapezoidal cross-section. The central portion 12 may also be plate-shaped.

The component 14 here comprises a plate comprising a contact surface 16 for contacting the pad 6 and an aperture 18 for receiving a fastening member of the pad 6. Pad 6 is secured to face 16 and is in contact with face 16. Preferably, the components 12 and 14 are formed as one piece.

A member 14 is formed at the distal end of the body portion 12. The surface 16 and the component 14 are substantially planar and extend here perpendicularly to the body part 12, for example horizontally. The shape and arrangement of the components 14 depends on the position of the power supply rails.

In practice, the external power track extends parallel to the longitudinal axis of the rail vehicle on which the device 2 is mounted, so that the pads 6 and faces 16 are aligned with the power track and the body portion 12 projects perpendicularly relative to one side of the vehicle.

In the example shown, the face 16 faces upwards when the device 2 is mounted on a rail vehicle to allow the pads 6 to make contact with the lower surface of the power rail, for example in the case of a capture mode of the top of the power rail.

According to a variant not shown, the face 16 is facing downwards, which allows the pad 6 to be in contact with the upper surface of the power supply rail, for example in the case of a capture mode of the top of the power supply rail.

The body portion 12 further comprises a proximal portion 20, by means of which proximal portion 20 the arm 4 is attached or anchored to the frame 8. For example, the end 20 comprises a hole 24, the hole 24 being intended to receive a fastening element 34, such as a screw or a threaded rod, to fasten and clamp the arm 4 on the frame 8. In fig. 1, only the head of the fastening element 34 is visible.

According to an example, the central portion 12 may include a curved portion 22 near the proximal portion 20.

In fig. 1, reference numeral 36 denotes an arm support belonging to the frame 8, here in the form of a bar. The arm support 36 is located below the arm 4 and allows the arm 4 to rest on the support 36.

According to the embodiment, the arm support 36 includes a positioning pin, for example, protruding from an upper surface of the arm support 36 while being integral with the arm support 36. The arm 4 advantageously comprises a receiving hole 38, in which receiving hole 38 the positioning pin is received when the arm 4 is in the mounted state. A hole 38 is formed in the central portion 12, for example, toward the end 20. The detent pin prevents the arm 4 from being misaligned or accidentally eccentric.

The device 2 further comprises an electrical circuit 10 collecting the drawn current, and a protective casing 30 or protective backplane at least partially enclosing the frame 8 and the electrical circuit 10.

For example, the housing 30 is made of an electrically insulating material.

For example, the circuit 10 includes one or more connection terminals connected to a power circuit embedded in a rail vehicle.

Thus, it will be understood that pad 6 is electrically connected to circuit 10 through arm 4. For example, the frame 8 is electrically conductive and connects the end 20 of the arm 4 to the circuit 10. According to one example, the circuit 10 includes an electrical protection device, such as a fuse.

Indeed, in certain applications, the use of a conductive arm 4 is preferred over the use of an insulated arm, since the insulated arm also requires the addition of a dedicated conductor, such as a cable or bus-type connecting rod, to electrically connect the pads.

According to an alternative and illustrative example, the frame 8 is shared by a mobile part fixed to the arm 4 and a fixed part, for example fixed to the casing 30. The moving part is free to move relative to the fixed part, here by pivoting about a horizontal axis parallel to the longitudinal direction of the part 14. One or more springs 32 (e.g. helical traction springs) extend between the fixed and movable parts of the frame 8 to return the movable part to a position in contact with the power supply rail. This allows the device 2 to be able to withstand any height variations of the power track relative to the rail and to exert a force on the track, which may ensure good current capture. In a variant not shown, the spring 32 may be replaced by a torsion spring mounted about the pivot link.

In practice, in the use configuration, the device 2 is mounted on a rail vehicle, for example by attaching a protective casing to the lower part of the rail vehicle, preferably to the bogie or the tank bottom of the rail vehicle. The same rail vehicle may comprise a plurality of devices 2 connected to the power supply circuit of the vehicle.

The apparatus 2 comprises a measuring device 40 to measure the mechanical force exerted on the arm 4. The measuring device 40 comprises a strain sensor in contact with the arm 4.

For example, the strain sensor is a strain gauge, also referred to as a strain gauge.

According to one illustrative example, each strain gauge comprises one or more layers of thin conductive material, preferably a metallic material.

When the gauge is deformed, for example due to the deformation of the surface on which it is deposited, the current characteristics of the gauge vary, which makes it possible to quantify the deformation of the gauge by measuring the variation of the current flowing through the gauge.

Preferably, the strain sensor may measure a force greater than or equal to 50N, or greater than or equal to 100N and less than or equal to 5000N, or less than or equal to 3000N, to which the arm is subjected when the strain sensor is in contact with the arm of the device 2.

This range of values allows the strain sensor to measure the deformation of the arm (typically less than 1000N), and also to detect the breakage of the arm (breaking force greater than 1000N).

For example, the measurement tolerance of the measuring device 40 for a force value interval greater than 1000N is higher than for a force value interval less than 1000N. For the latter interval, the measurement tolerance is preferably less than 5% or less than 2%.

According to an embodiment, the measuring device 40 is mounted on the arm 4, preferably on the central portion 12.

In the example shown, the device 40 is mounted on the upper surface 26 of the central portion 12, that is to say it forms a "receiving surface" for the strain sensor. The strain sensors are then brought into contact with the upper surface 26.

For example, in the present disclosure, a measurement device 40 is said to be "mounted" on a surface when a strain sensor of the measurement device 40 is mounted on the surface, that is, when it is fastened directly or indirectly to the surface.

According to other embodiments, the device 40 is mounted on one of the sides 28 of the central portion 12, that is to say one of the sides forms a receiving surface of the strain sensor. Subsequently, the strain sensor is brought into contact with said side 28.

For example, fig. 3 shows an arm 4' according to another embodiment. The arm 4 'is similar to the arm 4 except that the measuring device 40 is now fixed to the side 28 of the central portion 12 of the arm 4'.

Except for this difference, arm 4 'is similar to arm 4, and all that is described with reference to arm 4 can be converted into arm 4', so that only arm 4 is described hereinafter.

For example, placing the measurement device 40 on the upper surface 26 may more accurately measure the vertical component of the deflection force exerted on the arm 4, while placing the measurement device 4 on the upper surface 26 allows for more accurate measurement of the lateral bending force experienced by the arm 4'.

The measuring device 40 comprises at least one measuring unit 50, an example of which is shown in fig. 4. The strain sensors are included in one or more measurement units 50.

In this example, the measurement device 40 comprises a single measurement unit 50.

The measurement cell 50 includes an electrically isolated structure including a bond layer 52 and a ceramic layer 54 covering the bond layer 52.

Adhesive layer 52 is optionally deposited on a receiving surface of arm 4, such as on upper surface 26 or on one of sides 28. For example, the ceramic layer 54 is in direct contact with the bond layer 52.

According to an example, the adhesive layer 52 is adhesive, preferably thermosetting, such as epoxy.

A strain sensor, here with the reference numeral "56", is placed on the ceramic layer 54 and in indirect contact with the arm 4.

In the examples described, unless otherwise specified, the layers of the isolation structure are flat and have a substantially constant thickness (that is, a constant thickness within 10%, preferably within 5%).

Preferably, all or some of the strain sensors 56 are connected to each other within a measurement circuit, such as a wheatstone bridge.

For example, the measurement unit 50 includes four sensors 56 (only two sensors are visible in fig. 4) connected to each other to form a measurement circuit.

In variations, the number of sensors 56 may be different.

Advantageously, the sensors 56 are connected within each measuring circuit by conductive tracks, for example metal tracks, which are placed on the ceramic layer 54, for example in a similar manner to the conductive tracks of a printed circuit.

According to a variant, several measuring circuits are used in the measuring device 40. Each measurement circuit includes a group of a plurality of sensors 56. In this case, the groups of sensors 56 are preferably in contact with the same surface of the central portion 12 and spaced from each other, while being placed at different distances from the frame 8 to which the arm 4 is connected.

For example, two measurement circuits are aligned along the central portion 12, with a first set of sensors 56 positioned a distance D1 from a fixed point of the central portion 12, and a second set of sensors 56 positioned a distance D2 from a fixed point of the central portion 12.

According to a first example, the measurement device 40 comprises a measurement unit 50, which measurement unit 50 comprises at least two separate measurement circuits.

According to a second example, the measurement device 40 comprises two measurement units 50, each measurement unit 50 comprising a measurement circuit. Two measuring units 50 are placed at different locations on the surface of the central portion 12.

The stress to which the arm 4 is subjected can be measured differentially using a plurality of measurement circuits in contact with the same face of the arm. For example, the use of two measurement circuits allows the device 40 to determine the difference in the bending moment to which the arm 4 is subjected between the two measurement circuits. The sensitivity of the measuring device 40 is then proportional to the difference between the distances D1 and D2.

Advantageously, the measurement unit 50 may comprise a temperature sensor 58 placed in the vicinity of the at least one strain sensor 56.

For example, the temperature sensor 58 comprises a thermocouple or thermistor, such as a probe having a negative temperature coefficient.

The temperature data measured by the sensor 58 is particularly able to correct the deformations measured by the sensor 56 to take account of any drift due to high temperatures (for example due to heating of the device 2).

The temperature data measured by the sensor 58 may also be used to detect abnormal heating of the device 2 or to provide an indication of the current flowing through the arm 4.

In one variation, the temperature sensor 58 may be omitted.

According to an advantageous embodiment, the electrically isolating structure further comprises an encapsulation layer 60 made of resin or of electrically isolating varnish, which covers the strain sensors 56 and, where appropriate, also the associated conductive tracks.

For example, the encapsulation layer 60 is deposited on the ceramic layer 54, preferably only on the portion of the surface of the ceramic layer 54 where the strain sensor 56 is located. In other words, the encapsulation layer 60 partially covers the ceramic layer 54.

Advantageously, the electrically isolating structure further comprises an additional protective layer 62 made of an electrically isolating elastomeric material, for example made of silicone, which covers the encapsulation layer 60 and/or the ceramic layer 54.

According to an alternative embodiment, the measurement unit 50 includes a housing 64, the housing 64 being mounted on the receiving surface and defining an interior space in which the sensor 56 and the isolation structure are housed.

As an example, the measuring cell 50 here ensures a tightness level greater than or equal to the protection index IP66, for example due to the housing 64 and/or the additional protective layer 62.

For example, the housing 64 takes the form of a hollow plate bounded by planar walls, although other shapes, such as curved or circular, are also contemplated. The height h64 of the housing 64 is in this case less than or equal to 10cm or 1cm and preferably less than or equal to 5 mm.

According to an example, the housing 64 includes a fixing portion 66 in the form of a flange on its base, which enables the housing 64 to be fixed to a receiving surface (here, the central portion 12) using fastening members 68 such as screws or rivets. In one variation, the housing 64 may be secured by gluing or by welding, without the need for the securing portion 66.

As an illustrative example, the thickness e52 of the adhesive layer 52 is between 10 μm and 1 mm.

As a schematic example, the thickness e54 of the ceramic layer 54 is between 0.05mm and 3mm, preferably between 0.1mm and 0.5mm, more preferably between 0.2mm and 0.4 mm.

As an illustrative example, the thickness e60 of the encapsulation layer is between 5 μm and 0.5mm, preferably between 20 μm and 100 μm.

As an illustrative example, the thickness e62 of the additional protective layer 62, measured here with respect to the upper surface of the encapsulation layer 60, is between 0.5mm and 1cm, preferably between 1mm and 5 mm.

According to an embodiment, each of the binder forming layer 52 and the ceramic forming layer 54 has a dielectric strength greater than or equal to 10 kV/mm. The resin or varnish forming the encapsulating layer 60 has a dielectric strength of 100kV/mm or more.

According to an example, the measurement device 40 also allows interconnection of the sensor 56 with processing circuitry mounted on the rail vehicle.

For example, each cell 50 includes one or more conductive contact pads 70 disposed on the resin layer 54. For example, the pads 70 are connected to the sensor 56 by the aforementioned conductive traces. Each pad 70 is connected by a weld 72 to a cable 74 where the cable 74 exits the housing 64 to the interconnect circuitry.

Preferably, each cable 74 comprises an electrically insulating sheath, for example made of a polymer, in particular of PTFE, having a thickness at least 0.5mm greater than the radius of the core of the cable.

In the example shown, the pad 70, the weld 72, and a portion of the cable 74 are covered by the encapsulation layer 60.

According to an advantageous embodiment, the sensors 56 and the isolation structures of each unit 50 are manufactured in the same method directly on the receiving surface by successive thin layer deposition, for example using a vacuum deposition method.

For example, the first layer 52 is preferably deposited on the receiving surface after cleaning the receiving surface. Followed by the sequential deposition of other layers. The sensor 56 is preferably formed by depositing metal on the layer 54. The temperature sensor 58 is also formed by depositing metal, for example.

The geometry of the deposited layer may be defined during deposition using a mask and/or using an etching method such as chemical etching or ion beam etching. Such methods may also be used to impart a predetermined pattern to the deposited layer, for example, defining a pattern to produce sensor 56.

The conductive traces and pads 70 are fabricated under the same conditions using similar methods, where appropriate. For example, the weld 72 and placement and securement of the housing 64 are done later.

The manufacturing method may also comprise one or more heat treatment steps, in particular in order to build up one or more deposited layers, for example hardening the adhesive layer 52 after its deposition when it is a thermosetting adhesive.

Thanks to an embodiment of the invention, the measuring device 40 allows real-time measurement of the mechanical forces experienced by the arm 4. The isolation structure allows the strain sensor 56 to be in contact with the arm 4 while being electrically isolated from the arm 4.

In particular, since the sensor 56 is placed as close as possible to the arm 4, the measuring device 40 allows reliable measurements without increasing the risk of current leakage when the collected current circulates in the arm between the pad 6 and the circuit 10.

The isolation structure avoids the use of galvanic isolation circuits at the output of the sensor 56, which is advantageous because the addition of such galvanic isolation circuits increases the cost and complexity of the apparatus 2.

The isolation structure, in particular the layers 52 and 54, is here sufficiently fine to allow the sensor 56 to measure the deformation of the arm, while ensuring satisfactory electrical isolation of the sensor 56 with respect to the conductive arm 4, even when the arm 4 transmits the current collected from the power supply track.

For example, the isolation structure may ensure compliance with the electrical isolation level of standard CEI 60077 when the supply voltage of the external supply rail is equal to 750 vdc.

Fig. 5 shows a washer 80 of a third embodiment of a catching device according to the invention. In this embodiment, the strain sensor 56 of the measuring device 40 is located on a receiving surface formed by the outer surface of the washer 80.

In the example shown, the washer 80 includes a substantially cylindrical hollow body 82 that defines a central bore 84. The body 82 includes one or more planar portions 86 disposed on an outer peripheral surface of the body 82. The washer 80 here comprises two mutually opposite faces.

Reference character R80 denotes the inner radius of the central bore 84. Reference character L82 denotes the distance between the two faces 86. Reference L86 denotes the width of the face 86.

By way of example, the radius R80 is between 10mm and 20 mm. The distance L82 is greater than or equal to 10mm and less than or equal to 5 cm. The width L86 is greater than or equal to 5mm and less than or equal to 5cm or 2 cm.

In the mounted configuration of the device 2, the gasket 80 is at least partially housed in the receiving hole 38 and therefore forms part of the arm 4 here.

Fig. 6 shows a bottom view of the arm 4 (or the arm 4').

According to an embodiment, receiving aperture 38 includes a receiving area 90 arranged to receive an end of gasket 80. For example, the receiving area 90 includes a countersink, or chamfer, disposed on the lower surface of the component 12 about the receiving hole 38.

According to an example, receiving hole 38 includes a through hole sized to allow passage of a locating pin, and receiving area 90 has a diameter greater than the diameter of the through hole to receive at least a portion of washer 80 in receiving area 90 when washer 80 is installed around the locating pin.

In practice, the height of gasket 80 is greater than the depth of receiving area 90, so that gasket 80 protrudes from receiving hole 38, while protruding relative to the lower surface of central portion 12.

Thus, contact is provided between the arm 4 and the arm support 36 by the washer 80.

For example, the outer surfaces 82 and 86 of the gasket 80 are at least partially in contact with the radial surface of the receiving area 90.

Thus, it will be appreciated that in the assembled configuration, the washer 80 is compressively mounted between the central portion of the arm 12 and the arm support 36. The upper end of washer 80 contacts the bottom surface of receiving area 90 and the lower end of washer 80 contacts arm support 36. The locating pin is received in the central bore 84 of the washer 80 and in the through bore of the receiving bore 38.

Advantageously, the receiving area 90 comprises a housing 92 to allow the passage of the cable 74. For example, each housing 92 is formed by a radial widening of a counterbore. The housing 92 is preferably formed opposite the face 86.

In other words, in this embodiment, the measuring device 40 is integrated into the washer 80, which washer 80 is in turn integrated into the arm 4.

Apart from this difference, all what has been described previously in relation to the apparatus 2 and its operation in relation to the measuring device 40 and the measuring unit 50 is applicable to the gasket 80 and can be transferred to the present embodiment, so that these details are not repeated. In particular, one or more measuring cells 50 may be formed on face 86, rather than on face 26 or 28 of central portion 12 of arm 4.

Since the gasket 80 is located near the point of attachment of the arm 4 to the frame 8, the use of the gasket 80 enables more accurate measurement of the pressure exerted on the arm.

The washer 80 also makes it unnecessary to replace the measuring device 40 if the arm 4 breaks, since the measuring device 40 is placed on the washer 80 and the washer 80 can be removed from the rest of the arm 4.

In a variant, the various embodiments can be combined with each other, for example by using a washer 80 with a measuring device 40 and a measuring device 40 formed on the surface of the arm 4 or 4' as previously described.

According to other variants not shown, the measuring device may be integrated into the current capture device 2, the current capture device 2 being adapted to operate according to a lateral capture mode.

For example, the device comprises a frame, arms and pads which serve the same function as previously described, the contact faces of the pads facing laterally towards the laterally mounted power supply rails, e.g. the contact faces extending vertically. The arms are for example moulded such that the central portion comprises one or more levers hinged with the frame and the pad and, where appropriate, with each other.

Fig. 7 shows an instrumented current capture system 100 installed in a rail vehicle 102.

The system 100 comprises at least one capturing device 2, which capturing device 2 comprises a measuring apparatus 40 according to one of the preceding embodiments.

The system 100 also comprises an electronic control means 104 connected to the measuring device 40 by a first data link 106.

For example, the electronic control device 104 comprises a logic processing unit 108, here a microprocessor or microcontroller or a Digital Signal Processor (DSP), and a computer memory 110, in which computer memory 110 instructions in the form of software code are stored, which instructions can be executed to automatically implement a method according to any of the examples described below. In a variant, the electronic control means 104 comprise an application-specific integrated circuit programmed to perform one or several of the methods described.

The system 100 also comprises a second data link 112, a human-machine interface 114 authorizing interaction with the driver of the vehicle 102, an on-board computer 116 of the vehicle 102 and a telecommunication interface 118 adapted to communicate, preferably by wireless link, and is provided with a management centre 120 outside the vehicle 102.

For example, the system 100 comprises a processing unit, not shown, to condition the measurement signals from the sensors 56, e.g. filter and/or sample them, before being processed by the control device 104.

According to an example, the first link 106 is a wired link connected to the measurement device 40, for example by a cable 74. The wired link may include one or more dedicated cables or a multiplexed cable link. In a variant, it may be a wireless link, for example a radio frequency link, preferably a short range wireless link.

A second link 112 connects the control device 104 to an interface 114 and a computer 116 and an interface 118. The second link 112 is, for example, a wired data bus, such as an ADC type, for example a fieldbus.

According to an embodiment, the second link 112 and/or interface 114 and/or computer 116 and/or interface 118 may be items of equipment already present in the vehicle 102 and used in part by the system 100 when shared with other functions of the vehicle 102 (independent of the system 100).

By way of illustrative example, the interface 114 includes an electronic display screen and/or a light indicator and/or an audible indicator and/or a tactile indicator that is adapted to send a message or indication to the driver of the vehicle 102. The computer 116 is a TCMS type railway maintenance computer (for a train control and management system). The interface 118 includes a radio frequency antenna.

According to one example, the device 104 is programmed to automatically calculate the contact force between the pad 6 and the power supply rail from the deformation data measured by the sensor 56.

The calculation of the contact force is done using a predetermined formula, programmed or recorded in the device 104, for example depending on the geometry of the arm 4 and the position of the measuring device 40 in the device 2. In one example, the device 104 is programmed to automatically determine the status of the arm 4 and in particular to detect a break of the arm 4, for example when the force measured by the sensor 56 exceeds a predetermined threshold, or when the measured contact force exceeds a first predetermined threshold. For example, the first threshold corresponds to a lateral force greater than or equal to 1000N.

According to another example, the device 104 is programmed to measure the force experienced by the arm over time. The measurement may be made periodically or at predetermined times. The measurement results are stored, for example, in the computer 116, for example, in a log file, and/or transmitted to the maintenance center 120 via the interface 118.

Thus, at the output, the device 104 is programmed to provide information on the state of the arm 4 and information on the value of the pad/rail contact force, for example in real time or periodically over time.

Advantageously, when the temperature sensor 58 is used, the device 104 is also programmed to automatically correct the data measured by the sensor 56 according to the measured temperature. The temperature measured by the sensor 58 may also be provided at the output of the device 104 independent of the correction made.

According to an example, the device 104 or the computer 116 is programmed to send an alarm to the interface 114 when a break of the arm 4 is detected by the device 104 due to a measurement of the apparatus 40.

Accordingly, in response, the driver of the vehicle 102 may stop the vehicle immediately to avoid any damage to the vehicle or the railroad infrastructure.

According to another example, the device 104 or the computer 116 is programmed to record an abnormal condition of the arm detected by the device 104 as a result of the measurement of the apparatus 40, for example an abnormal damage of the arm, for example when the measured force exceeds a second predetermined threshold while remaining below the first threshold.

For example, a message reporting the event is automatically sent to the maintenance center 120 via the interface 118. The corresponding event may also be stored in a log file recorded in the memory of the computer 116. A warning may also be displayed on the interface 114.

The embodiments and variations considered above may be combined to produce new embodiments.