SLIPRING BRUSH COMPRISING STRUCTURED WIRES

Abstract

A method for making contact wires for sliprings comprising the steps of: coating and/or plating a wire with a first metal of the group of nickel, chrome or a combination thereof; coating and/or plating the wire with a second metal of the group of gold, silver, or a combination thereof; delivering laser radiation and generating an interference pattern of the laser radiation to the surface of the wire; heating the surface selectively as defined by the interference pattern, modifying of the crystal structure and/or providing protrusions and/or recesses due to melting and/or evaporation of the surface material.

Claims

1. A method for making contact wires for sliprings, the method comprising the steps of: a. pulling a wire through a drawing die, thereby impressing a surface structure into the wire; b. processing the wire by at least one of (i) coating and (ii) plating the wire with a first metal comprising at least one of nickel and chrome; and c. further processing the wire by at least one of (a) coating and (b) plating the wire with a second metal comprising at least one of gold and silver.

2. A method for making contact wires for sliprings, the method comprising the steps of: a. processing a wire by at least one of (i) coating and (ii) plating the wire with a first metal comprising at least one of nickel and chrome; b. further processing the wire by at least one of (a) coating and (b) plating the wire with a second metal comprising gold and silver; c. delivering laser radiation to an outer surface of the wire to generate an interference pattern of the laser radiation thereon; d. heating the outer surface selectively as defined by the interference pattern; and e. carrying out at least one of (i) modifying a crystal structure of a surface material, (ii) providing protrusions and/or recesses at the outer surface of the wire due to at least one of melting and evaporation of the surface material.

3. The method according to claim 2, by selectively applying the laser radiation to predetermined sections of the outer surface of the wire.

4. The method according to claim 2, wherein steps c, d, and e. are carried out before any of steps a. and b.;

5. The method according to claim 2, wherein steps c., d., and e. are carried out after any of steps a. and b.

6. A device for manufacturing of structured contact wires for sliprings, the device comprising a drawing die having protrusions and recesses, and a drive means for pulling a wire through the drawing die.

7. A device for manufacturing of structured contact wires for sliprings, the device comprising: at least one laser source configured to generate at least one laser beam; at least one beam-splitter configured to split the at least one laser beam into at least two partial beams; at least one optical component configured to interact with the at least two partial beams by one or more of deflecting, guiding, and collimating said at least two partial beams to redirect said at least two partical beams to a focus spot; and at least one transport means configured to handle a contact wire by one or more of transporting, guiding, and holding the contact wire at the focus spot.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In the following, the invention will be described by way of examples, and without limitation of the general inventive concept, based on embodiments and with reference to the drawings.

[0025] FIG. 1 shows a basic slipring.

[0026] FIG. 2 shows a side view of a slipring.

[0027] FIGS. 3, 4, 5, 6, 7, 8, 9, and 10 show different embodiments of wire structures.

[0028] FIG. 11 is a sectional view of a contact wire having a partially structured surface.

[0029] FIG. 12 is a sectional view of another contact wire having a partially structured surface.

[0030] FIG. 13 is a sectional view of another contact wire having a partially structured surface.

[0031] FIG. 14 shows a sliding brush with a sectioned surface running on a V-shaped sliding track.

[0032] FIG. 15 presents details of a section of a contact brush.

[0033] FIG. 16 shows a partial structuring of a contact wire.

[0034] FIG. 17 illustrates a device configured for laser-based structuring of contact wires

[0035] FIG. 18 shows a drawing die in a front view.

[0036] While various modifications and alternative forms of implementation of the idea of the invention are within the scope of the invention, specific embodiments thereof are shown by way of example in the drawings and are described below in detail. It should be understood, however, that the drawings and related detailed description are not intended to limit the implementation of the idea if the invention to any particular form disclosed in this application, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION

[0037] In FIG. 1, a basic slipring is shown. It comprises a cylindrical module 160 having at least one sliding track 161 of a conductive material such as metal, which is supported by an insulating body 162 (preferably made of a plastic material). The module is rotatable about a center axis 165. There may be present a stationary brush block 100, which comprises an insulating body 110 holding at least one contact wire 201, 202. The contact wires may be soldered by soldering connections 121, 122 into through-holes of the insulating body 110. The contact wires have corresponding contact areas 211, 212, at which they contact the module 160.

[0038] In FIG. 2, the slipring is shown in a side view. The cylindrical module shows sliding tracks 161 spaced apart by insulating body 162. The sliding tracks 161 have V-shaped grooves for guiding the contact wires. In this Figure, three sliding tracks 161 isolated from each other are shown together with corresponding brushes 202, which are also isolated from each other, thus allowing simultaneous transfer of three signals or three current paths over the slipring.

[0039] In FIGS. 3, 4, 5, 6, 7, 8, 9, and 10, different embodiments of wire structures are shown. As mentioned above, a contact wire 201, 202 preferably has a predetermined surface structure.

[0040] FIG. 3 illustrates a first embodiment of a contact wire 300 having first linear structures 301, 302, 303. These structures may be formed by recesses and/or protrusions, which may preferably be generated with the use of a drawing die.

[0041] FIG. 4 shows a second embodiment of a contact wire 310 having spiral structures 311, 312, 313, 314. These structures may be formed by recesses and/or protrusions, which may preferably be generated with the use of a drawing die.

[0042] FIG. 5 shows a third embodiment of a contact wire 320 having dotted structures 321, 322, 323, 324. These structures may also be formed recesses and/or protrusions.

[0043] FIG. 6 shows a fourth embodiment of a contact wire 330 having fine linear structures 331. These structures may be recesses or protrusions, which may preferably be made with a drawing die.

[0044] FIG. 7 shows a fifth embodiment of a contact wire 340 having fine spiral structures 341. These structures may be recesses and/or protrusions, which may preferably be made by a drawing die.

[0045] FIG. 8 shows a sixth embodiment of a contact wire 350 having fine dotted structures 351. These structures may be recesses and/or protrusions.

[0046] Specifically for manufacturing the embodiments of FIGS. 3, 4, 6, and 7, a structured drawing die may be used. Such a drawing die may have protrusions and/or recesses defining the surface structure of the wire during the process of fabrication of the wire with the use of the drawing die.

[0047] FIG. 9 shows a further embodiment of a contact wire 360 having a micro-pattern 361 which may be made by laser interference structuring. In this embodiment, the pattern is provided at the whole surface of the wire.

[0048] FIG. 10 shows a further embodiment of a contact wire 370 having micro-structures 371 at a section of the surface of the wire. As a contact wire does not contact a sliding track over its whole surface, it may be sufficient to provide a surface structure only at parts of the contact wire. This may furthermore simplify the process of laser structuring.

[0049] FIG. 11 illustrates the case of partial structuring of a contact wire 410, which has a wire body 411 and only a partial structure in a limited surface area 412. It is not necessary to provide structuring over the whole length of the contact wire, as it only stays in contact with the sliding track over a small section of its length. According to the idea of the invention, it is preferred to provide a structured surface only over a wire length in a range of 1 mm to 20 mm, most preferably in a range between 5 mm and 10 mm.

[0050] In FIG. 12, a cross-sectional view of a contact wire having a partially structured surface is shown. A contact wire 380 comprises core material 381, which may be based on steel or brass material. It furthermore has a surface section 382 of about half the circumference harnessed with the surface structure (that in this case subtends an angle of about 180 degrees, as viewed from the center axis of the wire).

[0051] In FIG. 13, a sectional view of a contact wire having a partially structured surface is shown. A contact wire 390 comprises core material 391, which may be based on steel or brass material. It furthermore has a 90 degree section 392 of the circumference provided with the structure.

[0052] In FIG. 14, a sectional view of a contact wire having a partially structured surface is shown. A contact wire 400 comprises core material 401, which may be based on steel or brass material. It furthermore has multiple (as showntwo) sections 402, 403, each subtending a respectively-corresponding angle (as viewed from the center axis of the wire) of the circumference (as shown45 degrees for each of the sections) and provided with the surface structure. It is these surface-structured sections of the wire that are preferably used in practice for operation with a V-shaped sliding track.

[0053] In FIG. 15, a sliding brush with a sectioned surface running on a V-shaped sliding track is shown. The sliding brush 420 is guided in a V-shaped groove of a sliding track 161, forming two separate contact areas. The surface of the brush wire core 421 has two structured areas 422, 423, which are located at the contact points between the wire brush 420 and the sliding track 161.

[0054] In FIG. 16, details of a section of a contact brush 440 are shown. The brush has a brush core 441 (which may comprise steel, brass, or any other metal or a combination thereof providing a comparatively stiff but spring-elastic structure). There are preferably at least two surface layers. Preferably, there is an inner layer 442, which comprises a hard metal like nickel. As shown, there is an outer layer 443, which comprises a material or metal having good electrical-contact characteristics, such as silver or gold, or a combination thereof. The inner and outer layers may be manufactured by coating or plating (preferably by electro-plating). The inner and/or outer layer may be structured as discussed above.

[0055] FIG. 17 discloses a device configured to effectuare laser-based structuring of contact wires. A laser 601 provides, in operation, a laser beam 602, which is further split with a splitting mirror 610 into at least two preferably equal (irradiance and/or other characteristic-wise) beams 611, 612. The second partial beam 612 is shown to be deflected by a mirror 615 such that the second partial beam and the first partial beam are both directed towards a focus spot 630. Additional lenses 620, 621 are optionally employed for focusing and/or collimating the first and the second laser beams 611, 612. In operation of the device, a contact wire 200 is moved along the area of the focus spot 630. This may be effectuated with a first spool 650 (storing unstructured wire) and a second spool 651 (for storing the already-structured wire). Both spools may be rotated, such that the wire is moved continuously and/or stepwise from one spool to another. There may be further guide rollers which are not shown in-here, or other guiding means for precisely guiding the contact wire at the focus spot. There may be further means for cutting the structured contact wire into pieces and moving these pieces to a container or mounting them directly into brush blocks.

[0056] FIG. 18 shows a drawing die 800 in a front view. The drawing die 800 has an inner opening 801 through which a wire is pulled. The inner opening has a structured contour providing protrusions 802 and recesses 803, thereby in operation producing a structured surface of a wire when it is pulled through the die.

[0057] It will be appreciated by those skilled in the art having the benefit of this disclosure that implementations of this invention are directed to provide structured wires for sliprings and a method for manufacturing of such wires. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.

LIST OF REFERENCE NUMERALS

[0058] 100 brush block [0059] 110 insulating body [0060] 121 soldering connection [0061] 122 soldering connection [0062] 160 slipring module [0063] 161 sliding track [0064] 162 insulating body [0065] 165 center axis [0066] 201 contact wire [0067] 202 contact wire [0068] 211 contact area [0069] 212 contact area [0070] 300 first contact wire embodiment [0071] 301, 302, 303 linear structures [0072] 310 second contact wire embodiment [0073] 311, 312, 313, 314 spiral structures [0074] 320 third contact wire embodiment [0075] 321, 322, 323, 324 spiral dots [0076] 330 fourth contact wire embodiment [0077] 331 fine linear structures [0078] 340 fifth contact wire embodiment [0079] 341 fine spiral structures [0080] 350 sixth contact wire embodiment [0081] 351 fine dotted structures [0082] 360 seventh contact wire embodiment [0083] 361 micropattern [0084] 370 eighth contact wire embodiment [0085] 371 microstructures [0086] 380 contact wire embodiment [0087] 381 core material [0088] 382 half circumference section [0089] 390 contact wire embodiment [0090] 391 core material [0091] 392 90 degree section [0092] 400 contact wire embodiment [0093] 401 core material [0094] 402, 403 45 degrees sections [0095] 410 contact wire [0096] 411 wire body [0097] 412 structured area [0098] 420 sliding brush [0099] 421 contact wire core [0100] 422, 423 structured areas [0101] 440 contact brush [0102] 441 brush core [0103] 442 inner layer [0104] 443 outer layer [0105] 601 laser [0106] 602 laser beam [0107] 610 splitting mirror [0108] 611 first partial beam [0109] 612 second partial beam [0110] 615 mirror [0111] 620 first beam lens [0112] 621 second beam lens [0113] 630 focus spot [0114] 650 spool storing unstructured wire [0115] 651 spool storing structured wire [0116] 800 drawing die [0117] 801 inner opening [0118] 802 protrusions [0119] 803 recesses