FR2830369A1 - COIL HOLDER FOR TRANSFORMER AND TRANSFORMER COMPRISING SAME - Google Patents

Abstract

The invention relates to a coil wedge (22) for a transformer intended to be interposed between an end of a coil (12A), and a structural element of the transformer. It has a first bearing surface (24) on the coil and an opposite second bearing surface (26) on the structure (20) of the transformer. According to the invention, it comprises adjustable means (28) for spacing the opposite bearing surfaces (24, 26) adapted to keep the two bearing surfaces (24, 26) apart according to at least two distinct configurations in which the intervals repairing the two bearing surfaces are different.

Description

can be connected to standard printed circuit connectors.

  The present invention relates to a coil shim for a transformer intended to be interposed between the end of a coil and a structural element of the transformer, of the type comprising a first bearing surface on the coil and a second opposite surface d 'support on the transformer structure. High power electrical transformers generally have several cylindrical coils arranged next to each other. A carcass defines a closed magnetic circuit along which the coils are arranged. The carcass comprises columns axially engaged inside each of the coils. On either side of the sections of the carcass connecting the columns engaged in the coils are arranged metal beams between which the coils are clamped, in order to prevent them from

  move axially along the length of the columns passing through them.

  Thus, the coils are supported on these beams at each of their ends. Between the longitudinal members and the ends of the coils are arranged insulating shims generally made of plastic material making it possible to avoid

  any play between the coils and the side members.

  Depending on the type of transformer, the gap to be filled between the end

  coils and side members arranged opposite is variable.

  Also, it is necessary to manufacture, for each type of transformer, shims having dimensions speciflcally adapted to the transformer considered. The transformer cost is therefore increased due to the birth

  stopped manufacturing specific shims.

  The object of the invention is to propose reel shims for transforming

  mateur and a transformer incorporating them whose cost is reduced.

  To this end, the invention relates to a coil wedge for a transformer of the aforementioned type, characterized in that it comprises adjustable means for spacing the opposing support surfaces adapted to hold the two surfaces support separated according to at least two distinct configurations in

  which the intervals repairing the two bearing surfaces are different.

  According to particular embodiments, the reel block com carries one or more of the following characteristics: - said adjustable spacing means comprise a first and a second body each carrying one of the first and second bearing surfaces, said bodies comprising complementary nesting profiles adapted for nesting in at least two distinct relative positions corresponding to said distinct configurations; - Said complementary nesting profiles of the first and second bodies include complementary grooves; the complementary grooves extend in a direction generally parallel to at least one of the bearing surfaces; the complementary grooves have essentially flat flanks applied one on the other during the compression of said shim between its two bearing surfaces, and said flanks applied one on the other extend parallel in addition to at least one of the bearing surfaces; - the grooves have a pitch of between 0.5 and 2 millimeters; - the number of splines is between 2 and 10; One of the bodies comprises a stud having a lateral surface generally of axis revolution extending substantially perpendicularly to the associated bearing surface, and the other body comprises a cavity delimiting a on the lateral face generally of complementary revolution to the lateral surface of the stud, and said complementary nesting profiles are provided on the surfaces generally of revolution of the first and second bodies; One of the bodies comprises a stud extending generally perpendicular to the associated bearing surface, and the other body delimits a yoke having two opposite lips encasing said stud, said complementary interlocking profiles being provided on the facing surfaces of the two lips and the corresponding surfaces of the stud; - The second body comprises a spacer on which is provided a nesting profile and a pad delimiting said bearing surface of the second body, and said pad comprises at least one abutment surface adapted to hold the profiles of 'complementary nesting; - The spacer and the shoe have cam / cam follower surfaces adapted to ensure engagement of the complementary nesting profiles under the action of the bringing together of the two bearing surfaces; and - the yoke is delimited by the spacer and the shoe defines a bowl of

  reception of at least part of the yoke engaged around the stud.

  The invention further relates to a transformer comprising at least one coil and at least one structural element, characterized in that it comprises at least one coil wedge as defined above, arranged between

  one end of the or each coil and the or each structural element.

  The invention will be better understood on reading the description which will

  follow, given only as an example, and made with reference to the drawings on

which: -

  - Figure 1 is a partial perspective view of a transformer according to the invention; - Figure 2 is an exploded perspective view of a wedge according to the invention arranged at the end of a coil; - Figure 3 is a cross-sectional view of the wedge assembled according to the invention; - Figure 4 is a perspective view of an element of the wedge according to the invention; and - Figures 5 and 6 are perspective views of a variant of re

  alization of two pieces of the wedge of figure 1.

  In Figure 1 is shown a three-phase transformer 10. This comprises three coils 12A, 12B, 12C of generally cylindrical shape extending parallel to each other. These coils are arranged in the same plane. The transformer comprises a magnetic circuit 14, comprising three columns 16A, 16B, 16C engaged axially in the coils 12A, 12B, 12C. These columns are connected to each other by lower and upper yokes

  laughs 18 of which only one is shown in Figure 1.

  Longers 20 are arranged on either side of the cylinder heads following their length. The coils 12A, 12B, 12C are held axially fixed along the length of the columns 16A, 16B, 16C by being sandwiched between the opposite lon gerons 20. Between the ends of each coil and the side members 20

  shims 22 are arranged according to the invention.

  Such a wedge is shown in exploded perspective in FIG. 2, and

  in end view, with partial cutaway in Figure 3.

  All the shims of a transformer are identical. They are carried out entirely in plastics. El include a surface 24 of a ppu i on the edge of a coil and a support surface 26 on the surface of the spar

  facing the coil. Advantageously, a damping pad, for example-

  ple silicone is interposed between the bearing surface 24 and the end of the coil.

  These two opposite bearing surfaces 24, 26 extend generally parallel to each other and are spaced from each other by a predetermined interval ended corresponding to the desired distance between the end of the coil and the

associated spar.

  According to the invention, each wedge 22 comprises adjustable means 28 for spacing the opposite bearing surfaces 24, 26 adapted to maintain the

  two surfaces spaced apart according to at least two distinct configurations in the

  which the intervals separating the two bearing surfaces are different.

  The bearing surface 24 on the end of the coil is defined on a first body 30 of the wedge while the bearing surface 26 on the spar 20 is defined on a second body 32 of the wedge itself constituted by a together

  parts as shown in figure 2.

  These first and second bodies 30 and 32 comprise complementary nesting profiles suitable for interlocking the two bodies with one another in at least two relative positions, thus ensuring adjustment

  the spacing of the opposite bearing surfaces 24, 26.

  More specifically, the first body 30 comprises a flat plate 34, one face of which forms the bearing surface 24. This bearing surface is bordered on one side by a rim 36 made of material and adapted to bear on the surface

  inner side of the coil, for example 12A.

  The body 30 comprises a stud 38 projecting from the surface of the plate 34 on the side opposite to the bearing surface 24. This stud 38 extends in the

  median part of the plate 34 over most of its length, this length

  along the radius of the coil.

  The stud 34 has, at its top, a flat surface 40 and, lateral-

  ment, two opposite side surfaces 41 extending parallel to one another. These lateral surfaces 41 extend along the length of the plate 34,

  perpendicular to the flange 36 bearing on the coil. When the hold is mounted

  ted on the reel, the lateral surfaces 41 extend substantially radially

relative to the coil.

  The surfaces 41 have fitting profiles adapted to cooperate with the complementary body 32 of the wedge. Advantageously, these pro s nesting threads comprise longitudinal grooves 42 extending along the entire length of the stud 38. These grooves extend generally parallel

lying on the support surface 24.

  As illustrated in FIG. 3 on a larger scale, each rib delimiting the grooves 42 has two opposite flanks made up of flat surfaces. A first sidewall 42A opposite the bearing surface 24 extends essentially parallel to this bearing surface. The second flank 42B is inclined relative to the bearing surface 24. Thus, the grooves define a set of flanks 42A parallel to the bearing surface 24 and staggered one above the

  other. These sides 42A form bearing surfaces for the second body 32.

  The number of ribs delimited by these grooves is preferably between 2 and 10 and is advantageously substantially equal to 5. The pitch of

  these grooves is between 0.5 and 2 millimeters.

  Additional nesting profiles 44 are provided on the

I S second body 32 of the hold.

  The latter comprises a spacer 46 and a support pad 48 on which the support surface 26 is formed. This support pad is itself constituted

a base 50 and a cross member 52.

  The spacer 46 generally has the shape of a trigger guard and delimits a yoke 54. The trigger guard 54 has two lips 56 connected to one another by a cross member 58. The fitting profiles 44 are delimited on the inner lateral surfaces of the lips, that is to say on their facing surfaces. These interlocking profiles consist of grooves extending parallel to the crosspiece 58. These grooves have characteristics complementary to the grooves 42 carried by the side walls of the stud 38. They extend along

parallel faces.

  More precisely, each rib delimiting the grooves has a support flank 44A opposite the support surface 26. This support flange extends pa parallel to the support surface 26. It is adapted to rest on a complementary support side 42A of the grooves of the first body 30. In addition, each

  that the groove has a side 44B inclined relative to the bearing surface 26.

  The length of the spacer measured in the direction of the grooves is equal to the length of the stud 38 also measures in the direction of the grooves. The outer lateral surfaces 60 formed on the lips 56 of the spacer are inclined relative to one another and converge towards each other

  following the direction of the cross 58.

  As illustrated in Figure 4, the base 50 has a generally square base 62. One of the faces of the base is hollowed out and delimits a bowl 64 for partial reception of the spacer 46 and in particular of a part thereof.

pledged around the plot-38.

  This bowl 64 has a flat bottom 66, bordered by four side walls

  ral. Two opposite side walls 68 extend parallel to one another.

  Their spacing is equal to the length of the spacer 28 measured in the direction of the grooves. The bowl is further delimited by two opposite flat side surfaces 70 having parallel generatrices. These surfaces are included

  born and converge towards each other towards the bottom of the bowl.

  The inclination of the surfaces 70 is identical to the inclination of the surfaces 60 of the spacer. The base 50 comprises a pillar-72 for connecting the cross-member 52. This pillar projects relative to the base 62 at the center of its face opposite to that in which the bowl 64 is formed. The pillar 72 has laterally grooves

  res 74. These grooves generally extend along the height of the pillar.

  The crosspiece 52 has a channel 76 delimited by two side walls 78 parallel to one another. The surfaces 80 facing the two side walls

  78 have grooves 82 complementary to the grooves 74.

  The bearing surface 26 is formed on the crosspiece 52 opposite the channel 76. Before installing the shim, the spacing separating the bearing surfaces

24 and 26 is defined.

  To this end, the spacer 46 is engaged on the stud 38 as illustrated in FIG. 3. The spacing of the spacer 46 and of the surface 24 is adjusted by choosing the relative position of the grooves 42, 44 engaged one in others, and in particular by engaging a determined number of protruding profiles and

in complementary hollow.

  The spacer 46 is put in place by sliding relative to the first body 30 in the direction defined by the complementary grooves 42, 44.

  The base 50 is then placed on the spacer 46 in order to cover partially

  this one. The spacer is then partially received in the bowl 64.

  The surfaces 60 and 70 are applied one on the other side, while the side surfaces 68 extend opposite the opposite open ends of the yoke 54. The crosspiece 52 is finally positioned on the base 50 by engaging the grooves 74, 80. The position of the crosspiece 52 is chosen

  by engagement of the stud 72 at the desired location in the groove 76.

  After adjusting the stop, it is installed in the transformer

between a coil and a spar.

  After mounting the stop, and while forces aimed at bringing surfaces 24 and 26 closer together are applied to the wedge by the spool and the spar,

  understands that the spacer 46 is held on the pad 38 and cannot be released from it.

  Indeed, the surfaces 68 of the bowl, extending opposite the non-grooved ends of the stud 38 constitute stops preventing any movement of the spacer 46 relative to the first body 30 in the direction of the grooves

42, 44.

  In addition, the surfaces 70 constitute abutments ensuring that the complementary grooves 42, 44 are kept in engagement. The surfaces 60 and 70 being in clinches, these form cam and cam follower surfaces which, under the action of bringing together of the two surfaces 24, 26, tend to urge the lips 56 of the spacer towards one another and thus ensure an even stronger engagement

grooves 42, 44.

  Such coil shims allow the spacing between the

  opposing bearing surfaces. This setting is obtained by choosing the number of channels

  straps engaged. Thus, these shims can be used in different ty-

  transformer weight, without the need for each type of transformer

  mateurs to make a new specific hold.

  The manufacturing cost of the transformer is thus reduced.

  In FIGS. 5 and 6 are presented elements constituting a va-

  laughing realization of a wedge according to the invention.

  A first body marked 130 visible in FIG. 5 is intended to be used

  sé to replace the first body 130 of the shim illustrated in FIGS. 2 to 4.

  In FIG. 6 is shown a spacer 146 intended to be used in replacement

spacer 46.

  In FIGS. 5 and 6, the elements identical or analogous to those of the first embodiment are designated by the same reference number to which was added 100. The first body 130 differs from the body 30 only in the shape of the stud 38

  projecting from the surface of the plate 134. In this embodiment

  tion, the pad 138 has a cylindrical lateral surface 202. The axis of this sur-

  cylindrical face extends perpendicular to the bearing surface 124 of the wedge

on the end of the spool.

  The lateral surface 202 has annular grooves 142 extending

  dant along the entire periphery of the stud. These grooves generally extend

  parallel to the bearing surface 124. They each have an identical shape

  tick in the shape of the grooves formed on the pad 38.

  Furthermore, and as illustrated in FIG. 6, the spacer 146 has, like the spacer 46, two lips 156 extending generally parallel to one another. These lips have on their facing surfaces, substantially in their median parts, depressions 204 defined by cylindrical facing surfaces 206. These cylindrical surfaces 206 are generated by a

  same generator and constitute parts of a cylinder extending perpendicular to

  lairement to the cross member 158 of the spacer. They delimit a housing of revolution-

  proper to the reception of the pad 138. For this purpose, the diameter of the cylinder defined by

  the surface 206 is equal to the diameter of the pad 138.

  The internal surfaces of the lips 156 have, according to all their

  lengths of the grooves 144. These grooves extend over the cy-

lindrics 206.

  These grooves have shapes identical to the grooves 44 and extend

  tooth parallel to each other.

  In FIG. 6, the crosspiece 158 has a central orifice 210 through

  from which a depression 204 is visible.

  The first body 130 and the spacer 146 are intended to be used

  with a base 50 and a cross member 52 as illustrated in FIG. 2.

  When mounting the shim and adjusting its thickness, the spacer 146 is engaged on the stud 138. To do this, the stud 138 is introduced between the lips 156 of the spacer. The ribs 142 are engaged with a number of complementary ribs 144 corresponding to the desired distance between the

two opposite surfaces of the wedge.

  The two lips 156 gradually move apart by elastic deformation S than from the cross member 158 in order to allow the displacement of the stud 138. This stud is moved, along the length of the ribs until it is received in the dice

pressures 204.

  In this position, the lips 156 relax, since they are no longer subjected to a stress aimed at removing them due to the presence of the pad 138. However, the complementary ribs formed on the pad and on the cylindrical faces 206 remain in grip, thus ensuring axial positioning of the

  first body 130 and spacer 136.

  The base 50 is then engaged on the spacer 146 in order to ensure, by wedge effect and as explained above, a bringing together of the two lips

  156 thus tending to accentuate the cooperation of complementary grooves.

  Finally, the cross member 52 is placed on the base 50.

  It is understood that in this embodiment, the pad 138 is susceptible

  to be moved in rotation relative to the spacer 146 around the axis of the stud.

  Indeed, the pad 138 is held axially between the two depres sions 204 with a cylindrical surface, the concavities of the cylindrical surfaces 206 and of

  the lateral surface 202 of the stud being identical.

  Thus, with such a shim, the crosspiece 52 can be positioned angularly relative to the first body applied to the end of the coil, facilitating

thus mounting the transformer.

Claims (13)

  1. Coil wedge (22) for a transformer (10) intended to be interposed between one end of a coil (12A, 12B, 12C), and a structural element (20) of the transformer, comprising a first surface d 'support (24) on the coil and a second opposite surface (26) bearing on the structure (20) of the transformer, characterized in that it comprises adjustable means (28) for spacing the opposite bearing surfaces t24, 26) adapted to keep the two support surfaces (24, 26) apart according to at least two distinct configurations in which the intervals repairing the two support surfaces are different. 2. Wedge according to claim 1, characterized in that said adjustable spacing means (28) comprise a first and a second body (30, 32) each carrying one of the first and second bearing surfaces (24, 26 ), said bodies (30, 32) comprising complementary interlocking profiles (42, 44j142 144) adapted for interlocking in at least two distinct relative positions   corresponding to said separate configurations.   3. Wedge according to claim 2, characterized in that said complementary nesting profiles of the first and second body (30, 32) comprise   complementary grooves (42, 44; 142,144).   4. Wedge according to claim 3, characterized in that said complementary lure rod (42, 44; 142, 144) extend in a general direction   LEMENT parallel to at least one of the bearing surfaces (24, 26).   5. Wedge according to claim 4, characterized in that the complementary grooves (42, 44; 142, 144) have essentially flat sides applied one on the other during the compression of said wedge between its two surfaces support (24, 26), and in that said flanks applied one on the other   extend parallel to at least one of the bearing surfaces (24, 26).   6. Wedge according to any one of claims 3 to 5, characterized   in that the grooves (42, 44; 142,144) have a pitch of between 0.5 and 2 thousand meters.   7. Wedge according to any one of claims 3 to 6, characterized   in that the number of grooves (42, 44; 142,144) is between 2 and 10.   8. Wedge according to any one of claims 2 to 7, characterized   in that one of the bodies (130) comprises a stud (138) having a lateral surface generally of axis revolution extending substantially perpendicular to the associated bearing surface (124), and in that the 'other body (146) com carries a cavity delimiting a lateral surface generally of revolution (206) complementary to the lateral surface of the stud (138), and in that said complementary fitting profiles (142,144) are formed on the general surfaces   element of revolution (202.206) of the first and second bodies.   9. Wedge according to any one of claims 2 to 8, characterized   in that one of the bodies (30, 32, 130, 146) comprises a stud (38, 138) extending generally perpendicular to the associated bearing surface (24, 124), and in that the other body (32,146) delimits a yoke (54,154) having two opposite lips (56,156) encasing said stud (38), said complementary interlocking profiles (42, 44; 142, 144) being formed on the surfaces facing the   two lips (56,156) and the corresponding surfaces of the stud (38,138).   10. Wedge according to any one of claims 2 to 8, characterized   IS in that the second body (32) comprises a spacer (46,146) on which is provided a nesting profile (44) and a shoe (48) delimiting said bearing surface (26) of the second body, and in that said pad (48) has at least one abutment surface (70) adapted to hold the interlocking profiles in engagement complementary (42, 44; 142,144).   11. Wedge according to claim 9, characterized in that the spacer (46) and the shoe (48) have cam / cam follower surfaces (60, 70) adapted to ensure engagement of the interlocking profiles complementary (42, 44; 142, 144) under the action of the bringing together of the two surfaces support (24, 26).   12. Wedge according to claim 9 and one of claims 10 and 11,   characterized in that the yoke (54) is delimited by the spacer (28) and the shoe (48) defines a bowl (64) for receiving at least part of the yoke (54) engaged around the stud (38).   13. Transformer comprising at least one coil (12A, 12B, 12C) and at least one structural element (20), characterized in that it comprises   at least one reel block (22) according to any one of the preceding claims   teeth, arranged between one end of the or each coil (12A, 12B, 12C) and   the or each structural element (20).