DEVICE AND METHOD FOR WIDENING AND TWISTING

Abstract

The present invention relates to a device (100) and a method for widening ends of legs of hairpin conductors arranged in slots of a stator core, and to a device (200) and a method for twisting ends of legs of hairpin conductors arranged in slots of a stator core. The device (100) for widening comprises at least one finger (111), preferably a plurality of fingers (111), for radially moving the ends of legs of hairpin conductors-said at least one finger (111) is arranged moveably in a radial inward and in a radial outward direction. Said at least one finger (111) is arranged moveably in an axial upward and in an axial downward direction. Said at least one finger (111) comprises at least one radially extending arm (101) and a separation member (102) being arranged adjacent to an, preferably radially inner, end of the arm (101). Said separation member (102) is designed for being positioned between two ends (5a, 5b) of radially neighbouring legs of pairs (6, 6′) of hairpin conductors. Said finger (111) has a first, preferably radially inner, section (104) adjacent to the separation member (102). Said first section (104) has a first radial width (114) dimensioned to receive at least one pair (6) of ends of legs and is adapted for moving said pair (6) of end of legs when the finger (111) is radially moved. Said finger (111) has a second, preferably radially outer, section (105), which does not overlap with the first section (104). Said second section (105) has a second radial width (116). Said first radial width (114) is smaller than the second radial width (116), and wherein said second section (105) is dimensioned to receive at least one pair (6) of legs without moving, when the finger (111) is radially moved.

Claims

1. A device for widening ends of legs of hairpin conductors arranged in slots of a stator core, said device comprising: at least one finger configured to radially move the ends of legs of hairpin conductors, wherein: said at least one finger is arranged to move radially inward and radially outward, and said at least one finger is arranged to move axially upward and axially downward; at least one radially extending arm; and a separation member being arranged adjacent to an end of said arm, wherein said separation member is designed for being positioned between two ends of radially neighboring legs of pairs of said hairpin conductors, and wherein: said at least one finger has a first section adjacent to the separation member, said first section having a first radial width dimensioned to receive at least one pair of ends of legs and is adapted for moving said at least one pair of ends of legs when said at least one finger is radially moved, said at least one finger has a second section, which does not overlap with the first section, said second section having a second radial width, and said first radial width is smaller than said second radial width, and said second section is dimensioned to receive at least one pair of legs without moving, when said at least one finger is radially moved.

2. The device of claim 1, wherein a separation web is arranged between the first section and the second section.

3. The device of claim 1, wherein said at least one finger is adapted to radially move a first end of said pair of legs over a radial moving distance and wherein a radial length of said arm is larger than the sum of said radial moving distance and at least twice a radial extension of said pairs of ends of said legs.

4. The device of claim 1, wherein: said at least one finger has a seat for axially receiving said ends of said legs of hairpin conductors; said seat comprises a first compartment providing said first section and having a first radial compartment width dimensioned to receive at least one pair of legs, and a second compartment providing said second section and having a second radial compartment width; and wherein said first radial compartment width is smaller than said second radial compartment width.

5. The device of claim 4, wherein said first compartment is dimensioned to receive exactly one pair of ends of said legs.

6. The device of claim 4 wherein said second compartment is dimensioned to receive at least two pairs of ends of said legs.

7. The device of claim 1, further comprising a plurality of circularly arranged fingers, and wherein said fingers are independently moveable.

8. A method for widening ends of legs of hairpin conductors arranged in slots of a stator core, said method comprising: positioning a separation member being connected to an end of a radially extending arm between two ends of radially neighboring pairs of legs of said hairpin conductors; radially moving at least one first pair of legs of said hairpin conductors by radially moving said separation member; disengaging said at least one first pair of ends of legs from said separation member; and radially moving said separation member to a radial position corresponding to the radial position of at least one second pair of legs while keeping said at least one first pair of legs stationary.

9. The method of claim 8, further comprising: inserting said at least one first pair of ends of legs in a first compartment of a seat of a finger, said first radial compartment having a first radial compartment width; moving said at least one first pair of legs radially by moving said finger radially; disengaging said at least one first pair of ends of said legs from said first compartment; radially moving said finger to a radial position corresponding to the radial position of at least one second pair of ends of legs; inserting said at least one second pair of ends of legs into said first compartment and inserting said at least one first pair of ends of legs in a second compartment having a second radial compartment width larger than said first radial width; and moving said second pair of ends of legs radially by moving said finger radially, while keeping the at least one first pair of ends of legs stationary.

10. A system for preparing ends of legs of hairpin conductors in a stator core for welding, comprising: a device for widening said ends of legs according to claim 1; and a device for twisting, comprising a first ring coaxial with a second ring and extending around a twisting axis, wherein each ring comprises an array of pockets and is relatively rotatable with respect to each other around said twisting axis.

11. The method claim 9 further comprising twisting said ends of legs of said hairpin conductors arranged in said slot of said stator core.

12. The device of claim 1, wherein said end of said arm is a radially inner end.

13. The device of claim 1, wherein said first section of said at least one finger is a radially inner section.

14. The device of claim 1, wherein the second section of said at least one finger is a radially outer section.

15. The device of claim 3, wherein said first end of said pair of legs is a radially outermost end of said pair of legs.

16. The device of claim 4, wherein said first compartment is a first radially inner compartment.

17. The device of claim 4, wherein said second compartment is a second radially outer compartment.

18. The method of claim 8, wherein said end of said radially extending arm comprises a radially inner end of said radially extending arm.

19. The method of claim 8, further comprising radially moving said second pair of legs by radially moving said separation member, while keeping said at least one first pair of legs stationary.

Description

[0118] The invention will be explained hereinafter with reference to the description of specific embodiments and the respective drawings, which show:

[0119] FIG. 1 a perspective view of a device for widening ends of legs of hairpin conductors;

[0120] FIG. 2 a perspective view of detail of a device for widening ends of legs of hairpin conductors;

[0121] FIG. 3 a further perspective view of detail of a finger of a device for widening ends of legs of hairpin conductors;

[0122] FIGS. 4a-4c a schematic illustration of method steps for widening ends of legs of hairpin conductors;

[0123] FIG. 5 a perspective view of a device for twisting ends of legs of hairpin conductors;

[0124] FIG. 6 a perspective view of a detail of a device for twisting ends of legs of hairpin conductors;

[0125] FIG. 7 a perspective view of a further detail of a device for twisting ends of legs of hairpin conductors.

[0126] FIG. 1 shows a perspective view of a device 100 for widening ends of legs of hairpin conductors.

[0127] The device comprises a plurality of fingers 111, for radially moving the ends 5a, 5b of legs of hairpin conductors (see FIG. 3).

[0128] The fingers 111 are circumferentially arranged with respect to a system axis T corresponding to the axis of a stator (not shown in the figures).

[0129] The fingers 111 are arranged moveably in a radial direction 106 and they are arranged moveable in an axial direction 107.

[0130] The fingers 111 are independently moveably.

[0131] FIG. 2 shows a perspective view of detail of a device 100 for widening ends 5a, 5b of legs of hairpin conductors (see FIG. 3).

[0132] Each finger 111 comprises at least one radially extending arm 101 and a separation member 102 being arranged adjacent to a radially inner end 108 of the arm 101.

[0133] The separation member 102 is designed for being positioned between two ends 5a, 5b (see FIG. 3) of radially neighbouring legs of pairs of hairpin conductors.

[0134] Each finger 111 has a first, radially inner, section 104 adjacent to the separation member 102. The first section 104 has a first radial width 114 dimensioned to receive at least one pair of legs 5a, 5b (see FIG. 3) and is adapted for moving said pair of legs 5a, 5b (see FIG. 3) when the finger 111 is radially moved.

[0135] Each finger 111 has a second, radially outer, section 105, which does not overlap with the first section 104. Said second section 105 has a second radial width 116.

[0136] The first radial width 114 is smaller than the second radial width 116. The second section 105 is dimensioned to receive at least one pair of legs 5a, 5b (see FIG. 3) without moving, when the finger 111 is radially moved.

[0137] A separation web 118 is arranged between the first section 104 and the second section 105.

[0138] FIG. 3 shows a perspective view of detail of a finger 111 of a device 100 for widening ends 5a, 5b of legs of hairpin conductors.

[0139] Each finger 111 has a seat 112 for axially receiving the ends 5a, 5b of legs of hairpin conductors. The seat 112 comprises a first, radially inner, compartment 113 providing the first section 103 and having a first radial compartment width 114 dimensioned to receive one pair 6 of legs, and a second, radially outer, compartment 115 providing the second section 105 and having a second radial compartment width 116. The first radial compartment width 114 is smaller than the second radial compartment width 116.

[0140] The second compartment 115 is dimensioned to receive at least two pairs 6 of ends 5a, 5b.

[0141] FIGS. 4a-4c show a schematic illustration of method steps for widening ends of legs of hairpin conductors.

[0142] The fingers 111 are adapted to radially move the, preferably at least radially outermost, ends 5a, 5b of the pair 6 of ends of legs over a radial moving distance 117.

[0143] The second radial width 116 is larger than the sum of said radial moving distance 117 and at least twice of the radial extension 110 of the pairs of ends of legs.

[0144] The second radial width 116 preferably is in a range of 11 mm to 23 mm.

[0145] The radial width 119 of the first section 104 preferably is in a range of 4.5 mm to 10.5 mm.

[0146] The circumferential width 120 of the first section 104 and the second section 105 preferably is in a range of 2.5 mm to 5.5 mm.

[0147] A radial length 103 of the arm 101 is larger than the sum of said radial moving distance 117 and at least twice of the radial extension 110 of the pairs of ends of legs.

[0148] In a first step a separation member 102 is positioned between two ends of radially neighbouring pairs 6, 6′ of legs of hairpin conductors (see FIG. 4a).

[0149] The first pair 6 of legs of hairpin conductors is radially moved by radially moving the separation member 102. The first pair 6 of ends of legs is disengaged from said separation member 102. The separation member 102 is then radially moved to a radial position corresponding to the radial position of at least one second pair 6′ of legs, whilst keeping the at least one first pair 6 of legs stationary (see FIG. 4b).

[0150] The second pair 6′ of legs is radially moved by radially moving said separation member 102, whilst keeping the first pair 6 of legs stationary.

[0151] FIG. 5 shows a perspective view of a device 200 for twisting ends 5a, 5b of legs of hairpin conductors (see FIG. 7).

[0152] The device 200 comprises a plurality of pairs 201, 201′, 201″ of adjacent rings 202, 203 (see FIG. 6). The device 200 comprises an actuation apparatus 214 for independently moving the rings 202, 203 in circumferential directions 204, 205.

[0153] FIG. 6 shows a perspective view of a detail of a device for twisting ends 5a, 5b of legs of hairpin conductors (see FIG. 7).

[0154] Each pair 201, 201′, 201″ of adjacent rings comprises a radially outer ring 203 and a radially inner ring 202.

[0155] Each of said inner ring 202 and outer ring 203 comprise open pockets 206, 207 for receiving the end 5a, 5b of leg of a hairpin conductor (see FIG. 7).

[0156] The open pockets 207 in said radially outer ring 203 have a radial outer wall 208 and a radially inner, open end 209.

[0157] The open pockets 206 in said radially inner ring 202 have a radial inner wall 210 and a radially outer, open end 211.

[0158] Each open pocket 206 of the inner ring 202 forms a joint closed pocket 212 with a respective open pocket 207 of the outer ring 203 when the inner ring 202 and the outer ring 203 are circumferentially aligned. The joint closed pockets 212 each have the radial outer wall 208 of an open pocket 207 of the outer ring 203 and the radial inner wall 210 of an open pocket 206 of the inner ring 202.

[0159] FIG. 7 shows a perspective view of a further detail of a device for twisting ends of legs of hairpin conductors.

[0160] At least one of said inner ring 202 and said outer ring 203 is moveable in a circumferential direction 204 relative to the other ring 202, 203. Preferably said inner ring 203 and said outer ring 202 are moveable in circumferential opposite directions 204, 205.

[0161] Each open pocket 206 of the inner ring 202 forms a joint closed pocket 212 for receiving a pair of end 6 of legs 5a, 5b with a respective open pocket 207 of the outer ring 203 when the inner ring 202 and the outer ring 203 are circumferentially aligned.

[0162] The rings 202, 203 are circumferentially moveable, such that open pockets 206 of the inner ring 202 and open pockets 207 of the outer ring 203 form first joint closed pockets 212 in a starting position and form second joint closed pockets in an end position. New pairs of ends of legs are formed, which are housed in the second joint closed pockets.