FR2775840A1 - Moving structure electrical feed mechanism - Google Patents

Abstract

The prong section has track connection pads which allow relative movement along conductor tracks, and the unit has a spring allowing vertical movement.

Description

i The invention relates to a supply device

  electric between a fixed frame and a mobile structure.

  Such a device is applicable in several technical fields, in particular for supplying current to a load, such as an electric motor, supported by a structure.

mobile ture.

  In particular, in the field of shipbuilding, there are assemblies installed under the hull of a ship and comprising a motor for rotating the propulsion propeller of a ship, this assembly being capable of pivoting around a substantially vertical axis in order to orient the propeller so as to determine the direction of progression of the

  ship. This set contributes to propulsion and steering

  tion of the ship. Given the tonnage of current ships, such an assembly must be able to be supplied electrically with high power, without the misalignment of its component parts, which can be large, disturbing the electrical connection. In addition, this connection must take place when the assembly located under the ship is likely to perform more rotations

of a turn around its axis.

  Another field of application of the invention is that of the production of electricity by wind turbine, because the assembly constituted by the head of the wind turbine must be able to operate, according to the orientation of the wind, a rotational movement.

  around a substantially vertical axis.

  Finally, the invention is also applicable to the armaments field, in particular for the electrical supply of a

  tank turret, to that of the production of metallic sheets

  ques by electroplating on a drum rotating in an electrolyte, and that of coating, zinc plating or lacquering, by using electrostatic phenomena between

  two electrodes rotated.

  It is known to use graphite-based brushes to ensure electrical contact between a fixed part and a moving part. These brushes are effective over a relatively narrow operating temperature range, so they are not necessarily suitable for severe outdoor conditions

  as they may exist in the fields of application

  mentioned above. The contact between these brushes and the part or parts with which they are in sliding contact is of such a nature that the density of the current, that is to say the amperage per unit area of the contact, is limited. The electrical power transmitted by this type of contact is therefore relatively low, unless there are large contacts. In addition, in known systems comprising contact with a graphite brush, the resistivity of the contact

  is such that it generates a strong voltage drop, that is

  say a parasitic consumption and a risk of overheating.

  In addition, the graphite brushes can adhere in their cage and / or on the part of which they are not integral. This phenomenon, commonly called "sticking", occurs in particular when the mobile elements are immobilized for a relatively long period of time, while an electric current flows through the contact made by means of the brush. This bonding has the effect of increasing the torque necessary for setting in motion, or even damaging both the brush and the surface with which it must have sliding contact, which causes an increase in contact resistivity and a

  overheating prejudicial to the proper functioning of the assembly.

  To avoid these problems, it has been possible to envisage permanently animating the mobile assemblies with a movement of small amplitude intended to avoid sticking of the brushes. This movement consumes energy, requires the oversizing of the drive members and induces a degradation of the total energy efficiency of the system since part of the energy must be devoted to the perpetual movement of the

mobile part of the device.

  Finally, known systems do not easily tolerate tolerances

  these dimensions of the parts provided for making the electrical contacts. Now, these pieces can be large

  dimensions, especially in the applications envisaged above

  above, so they must be produced with great precision to avoid contact faults. This increases all the more the cost price of the device incorporating

these parts.

  It is to these disadvantages that we hear more particularly

  remedy the invention, by proposing a connection device

  electrical of the aforementioned type in which normal dimensional tolerances are acceptable for the components of the electrical connection, while the risks

  bonding or heating are significantly reduced.

  In this spirit, the invention relates to a device

  power supply between a fixed chassis and a structure

  ture movable in rotation about a fixed axis with respect to this chassis, this structure comprising several conductive annular tracks centered on this axis, each track being electrically connected to an electrical terminal carried by this chassis, characterized in that the electrical connection between each track and the corresponding terminal is produced by at least one clamp formed by two blades arranged on either side of the terminal, these blades being provided with elastic loading means in

  direction of the terminal and / or the track.

  The conductive clips of the invention replace before-

  carefully known brushes and devices without having the disadvantages. The fact that the blades are loaded elastically in the direction of the track and of the terminal allows them to remain in electrical contact with these elements, including

  included in the event of misalignment.

  According to advantageous aspects of the invention, the device incorporates one or more of the following characteristics: - each blade carries, on its face opposite the track, at least one stud capable of exerting sliding contact on this track; each blade carries, on its face opposite said terminal, at least one stud capable of exerting contact on the terminal, the contacts between the studs of the pliers of the clamp forming, in section perpendicular to the track and to the terminal, an articulated quadrilateral supporting the elastic load means; - The electrical connection comprises several juxtaposed clamps, each clamp being provided with individual means of elastic load; - the pads intended to cooperate with the track are arranged opposite distinct circumferences on the track; - The blades of the clamps of the same electrical connection have substantially all the same impedance; - The track is metallic, especially copper possibly coated with silver, while the stud in contact with the track is also metallic, especially copper or silver; each track is electrically connected to a busbar arranged, for the most part, according to a

  overall direction parallel to the fixed axis, each bar extends

  dant up to near one end of the mobile structure; - The ends of the busbars connected to the tracks are distributed in a generally helical configuration centered on the fixed axis; - The mobile structure, the tracks and the bars form a rigid assembly able to be driven in rotation about the fixed axis, by its base and / or its upper part; - the terminals associated with the tracks are distributed alternately in at least two fixed columns with respect to the

  chassis, these terminals being separated by insulating spacers

your.

  The invention also relates to a propellant and steering assembly for a ship comprising an electrical connection device as described above. This propellant assembly allows an efficient transfer of energy to a propulsion and steering group of the ship when it must not be rotated artificially to avoid

risk of sticking.

  The invention will be better understood and other advantages thereof will appear more clearly in the light of the

  description which follows of an embodiment of a

  electrical connection device in accordance with its principle, given solely by way of example and made with reference to the accompanying drawings in which: - Figure 1 is a perspective view of a device according to the invention; - Figure 2 is an elevational view of the device of Figure 1; - Figure 3 is a section along line III-III in Figure 2; - Figure 4 is a longitudinal section, on a larger scale, of detail IV in Figure 2; - Figure 5 is a top view of the device of Figure 4; - Figure 6 is a schematic representation of the principle of articulation of a clamp of the invention; - Figure 7 is a schematic perspective representation of the spatial distribution of the busbars associated with the annular tracks of the device of Figures 1 to 5. The electrical connection device shown in Figure 1 is intended for the power supply of a ship's powertrain located in a drive assembly

  and orientation of a ship's propeller.

  This device comprises a chassis 1 intended to be fixed relative to the not shown hull of the ship. This chassis is formed by several feet supporting it a base plate 1b. In the plate 1b is disposed a bearing 2 centered around an axis XX 'fixed relative to the frame 1. On the bearing 2 is mounted, free to rotate about the axis XX', a structure 3 intended to be made integral an electric motor

  which is not shown.

  The structure 3 comprises several electrically conductive annular tracks 4 centered on the axis XX 'and arranged in planes generally perpendicular to this axis. The chassis 1, meanwhile, carries terminals 5 in the form of plates, in a number equal to that of the tracks 4. Each terminal 5 is supplied with an electric current phase by means of a cable 6. For clarity of the drawing, only some cables 6 have been represented in FIG. 1. The terminals 5 are distributed in

  two columns A and B and separated from each other by spacers

  its insulators 7. The terminals 5 are arranged alternately in each of the columns A or B, this arrangement making it possible to obtain a satisfactory compactness of the chassis 1 while allowing access to the terminals 5 and to the elements which they

  support or to which they are connected.

  The tracks 4 are also separated by insulating spacers 8 while the lower part of the structure 3 is formed by a ring 9 on which is likely to engage a device for driving the structure 3 in rotation around the axis. XX '. The drive could also be engaged with a ring similar to

  the ring 9 and disposed in the upper part of the structure 3.

  As can be seen more particularly from FIGS. 4 and 5, the electrical connection between each track 4 and the corresponding terminal 5 is produced by clamps 20 formed by two blades 21 and 22 arranged on either side of terminal 5 and s' extending on either side of track 4. We denote e_ the thickness of terminal 5, we denote e. the thickness of the track 4. As the thickness e is less than the thickness e_, the blades 21 and 22 are each provided with a curvature or camber 21a, 22a making it possible to compensate for this difference in thicknesses, so that each strip 21 or 22 is generally parallel to the track 4, at its first end 21b or 22b, and at terminal 5, at its second end 21c or 22c. Reverse curvatures of the blades 21 and 22 could be provided if the thickness e of the terminal 5 was greater than the thickness e of the track 4. The blades 21 and 22 are mounted on the terminal 5 by means of a pin 23 passing through a blade and then the

terminal 5, then the other blade.

  A rod 24 also passes through the two blades and the terminal 5. This rod is provided at each of its ends with springs 25 and 26 bearing on flanges 24a and exerting on the blades 21 and 22 thrust forces F directed towards terminal 5. Thus, the ends 21b and 22b of the blades 21 and 22 are folded back towards the track 4, which guarantees a

effective electrical contact.

  The possible thickness defects of track 4 are naturally compensated for by the opening and closing movements of the clamp 20 which tends to close under

  the effect of the forces F exerted by the springs 25 and 26.

  Each blade 21 and 22 carries, respectively in the vicinity of its end 21b or 22b and on the side of the track 4, a metal stud 27 or 28, for example made of copper or silver, intended to constitute the sliding electrical contact between each blade 21 or 22 and track 4. It would also be possible to provide that each blade 21 or 22 carries several studs 27 or 28 in order to make several sliding contacts in parallel. Track 4 is also made of metal, for example copper, optionally coated with silver, silver or a metal alloy. The contact between track 4 and pads 27 and 28 is thus a metal / metal contact which induces a very low voltage drop. Indeed, the resistivity of the metal / metal contact of the entire device of the invention can be estimated on the order of micro-ohms, while the resistivity of an equivalent device equipped with graphite contacts would be of the milli-ohm order, which would cause drops of

  much greater tension and overheating.

  Each blade 21 and 22 carries, respectively near its end 21c or 22c and on its face directed towards the terminal, at least two contact pads 29 or 30, bearing against the terminal 5. As before, the contact thus produced is of the metal / metal type, because terminal 5 is made of copper, silver or

a metal alloy.

  The spatial distribution of the pads 27 and 29 which are arranged in a triangle in a plane parallel to that of FIG. 5 avoids a possible tilting of the blade 21 around its greatest axis. The same applies to the distribution of

pads 28 and 30 for blade 22.

  In view of the above, the contacts between the studs, the track and the terminal can be modeled in the plane of FIG. 4, like an isosceles articulated trapezoid T, slightly open, the bases of which formed between the studs 27 and 28 d 'a

  on the other hand, 29 and 30 on the other hand, remain permanently parallel

  the. This makes it possible to understand, under the effect of the springs 26 and 27, the possible misalignments of the track 4 relative to the terminal 5, as shown diagrammatically, in

  solid lines and dashed lines in Figure 5.

  It is noted that the rod 24 is mounted floating in an orifice 31 of the terminal 5, which allows the springs to elastically load the bars 21 and 22 constantly, regardless of the configuration of the isosceles trapezoid T mentioned above. Indeed, the rod 24 and the springs 25 and 26 are supported only by the blades 21 and 22 which physically constitute the trapezoid T, the rod 24 being simply guided in the orifice 31. Thus, the contact force between the studs 27 and 30 and parts 4 and 5 remains substantially constant.

  Other forms of quadrilateral are also envisaged.

  instead of the trapezoid T. In fact, the electrical connection between terminal 5 and track 4 comprises five clamps 20 distributed over the width of terminal 5, as shown in FIG. 5. These five clamps are arranged in a in such a way that the studs 27 and 28 which they comprise are situated on separate circumferences C1, C2, C3, C4 and Cs on the track 4. This makes it possible to distribute the risks of wear on the surface of the track 4 and keep the majority of contacts in the event of a fault located on one of

these circumferences.

  Each clamp 20 has its own elastic loading means, that is to say a rod 24 and a pair of springs 25 and 26, so that variations in thickness of the track 4 or the relative height of the track 4 and of terminal 5, across the width of the five clamps 20, are individually compensated

by each of these clips.

  The blades 21 and 22 belonging to the clamps 20 are made

  sées in the same material and have substantially identical dimensions, so that they have the same impedance, that is to say mainly the same resistance to the current which

  crosses them. This allows the power to be evenly distributed

  electrical circuit passing between each terminal 5 and each track 4 between the different clamps, without creating a privileged path in which the constraints would be concentrated

electrical or mechanical.

  The device shown comprises thirteen tracks 4 and thirteen terminals 5 making it possible to pass thirteen electrical phases that can be used by different loads, such as the drive motor of a propeller, the orientation device of the assembly located under the hull of the ship, control systems, etc. Of course, the number of tracks

  4 and terminals 5 can be modified according to the uses

  tions, it being understood that it is advantageously kept equal or multiple of the number of electrical phases to be transmitted. The dimensions of the tracks 4, the terminals 5 and the spacers 7 and 8 depend essentially on the voltages and the currents of use. Each track 4 is connected to a conductive bar 41z at

  4113 arranged generally parallel to the axis XX 'and extends

  dant up to near the ring 9. These bars 41 can be connected to electrical terminals 46 of which only a few have been shown in Figure 2 for clarity thereof. In its upper part 41a, each bar 41 is generally parallel to the plate 4 on which it is mounted. It is then bent at about 90 to form a rectilinear strip 41b which extends parallel to the axis XX 'to a lower end 41c. The bars 41 are numbered in ascending order, from the bar connected to track 4 closest to the ring 9 to the bar connected to track 4

the most distant.

  As is clearer from Figures 3 and 6, the

  upper parts 41a of the bars 41 are evenly distributed

  rement around the XX 'axis, in a configuration avoiding

  risk of electrical interference or overheating.

  The eight bars 41z to 418 of the eight lower tracks 4 are angularly distributed with an angular difference a equal to approximately 45. The upper parts 41a of the four bars 419 to 41: 2 situated above the previous ones are longer than the parts 41a of the bars 41z to 418, so that the vertical parts 41b of the bars 419 to 4112 are arranged closer to the 'axis XX' extending in the direction of the ring 9. We denote by X the angular difference between the bars 419 to 4112. This angular difference is of the order of 90. Finally, two bars 413 connected to the upper track 4.3 extend to the immediate vicinity of the axis XX ', so that their main parts

  substantially vertical 41b are distant from the corresponding parts

of bars 41z and 4112.

  The upper ends 41a, bars 41 are distributed in a generally helical configuration centered on the axis XX '. Other configurations can be

  envisaged according to the number of phases to be transmitted.

  As the structure 3 constitutes a rigid assembly, it can be rotated through the ring 9 thanks to a

gear motor not shown.

  The device of the invention has been shown while the

  electric current flows from the fixed chassis to the mobile structure.

  It can also be used to power a chassis

  fixed from a mobile structure.

  The device of the invention has been described with reference to

  a propellant and steering system for ships. It is however

  can be used in other applications, in particular

those mentioned above.

Claims (12)

  1. Power supply device between a fixed chassis (1) and a structure (3) movable in rotation about an axis (XX ') fixed relative to said chassis, said structure comprising several conductive annular tracks (4)   centered on said axis, each track being electrically connected   ment to an electrical terminal (5) carried by said chassis, characterized in that the electrical connection between each track and the corresponding terminal is produced by at least one clamp (20) formed by two blades (21, 22) arranged on the side and else   of said terminal, said blades being provided with means (24-   26) elastic load (F) towards said terminal and / or of said track.   2. Device according to claim 1, characterized in that each blade (21, 22) carries, on its face opposite said track (4), at least one stud (27, 28) capable of exerting contact sliding on said track.   3. Device according to claim 2, characterized in that each blade (21, 22) carries, on its face opposite said terminal (5), at least one stud (29, 30) capable of exerting contact on the terminal , the contacts between the studs (27-30) of the blades (21, 22) of said clamp (20) forming, in section perpendicular to said track (4) and to said terminal (5), an articulated quadrilateral (T) supporting said charging means (24-26) elastic (F).   4. Device according to one of claims 1 to 3,   characterized in that said electrical connection comprises several clamps (20) juxtaposed, each clamp being provided   individual means (25, 26) of elastic load (F).   5. Device according to claims 2 and 4, characterized   in that the studs (27, 28) intended to cooperate with said track (4) are arranged facing circumferences (C1-C5) separate on said track.   6. Device according to claims 4 or 5, characterized   in that the blades (21, 22) of the clamps (20) of the same connection   all have substantially the same impedance.   7. Device according to one of claims 2 to 5,   characterized in that said track (4) is metallic, in particular   ment in copper possibly coated with silver, while said stud (27, 28) in contact with said track is also metallic, in particular copper or silver.   8. Device according to one of the preceding claims,   characterized in that each track (4) is electrically connected   cally to a conductive bar (41) arranged in a direction generally parallel to said axis (XX '), each bar extending near to one end (9) of said mobile structure (3).   9. Device according to claim 8, characterized in that the ends (41a) of said conductive bars (41)   connected to said tracks (4) are distributed according to a configuration   globally helical tion centered on said axis (XX ').   10. Device according to one of claims 8 or 9,   characterized in that said structure (3), said tracks (4) and said bars (41) form a rigid assembly able to be driven in rotation to said axis (XX ') by its base (9) and / or its upper part.   11. Device according to one of the preceding claims,   characterized in that the terminals (5) associated with said tracks are alternately distributed in at least two columns (A, B) fixed relative to said chassis, said terminals being separated by insulating spacers (7).   12. Propulsion and steering assembly for a compressed ship   with an electrical connection device (1-46) according to   one of the preceding claims.