Coil forming apparatus and method of forming coils of rotary electric machine

• US 20050166393A1
• Filed: 01/18/2005
• Published: 08/04/2005
• Est. Priority Date: 01/30/2004
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Sawada, Yukinori
• Granted Patent: US 7,293,350 B2
• Time in Patent Office: Days
• US Class Current: 29/732
• CPC Class Codes: H02K 15/0428 characterised by the method or apparatus for simultaneously twisting a plurality of hairpins for simultaneously twisting a plurality of hairpins open ends after insertion into the machine H02K15/0087
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine
• CPC Class Codes: Y10T 29/49071 by winding or coiling
• CPC Class Codes: Y10T 29/49073 by assembling coil and core
• CPC Class Codes: Y10T 29/5137 including assembling or disassembling station
• CPC Class Codes: Y10T 29/5141 and means to stake electric wire to commutator or armature in assembling of electric motor or generator
• CPC Class Codes: Y10T 29/53143 Motor or generator

Abstract

A coil forming apparatus includes a twisting formation unit that twist-forms a predetermined number of U-shaped conductor segments. The twisting formation unit includes a first twisting formation jig composed of a first inside ring and a first outside ring and a second twisting formation jig composed of a second inside ring and a second outside ring. Each of the first and second inside rings has the same number of circumferentially disposed holding slots as the stator slots to hold one of each pair of straight portions. Each of the first and second outside rings has the same number of circumferentially disposed holding slots as the stator slots to hold the other of each pair of straight portions of the U-shaped conductor segments. The first and second inside rings and the first and second outside rings are coaxially coupled to shift relative circumferential position between the inside rings and the outside rings by a predetermined angle to twist the turn portions of the U-shaped conductor segments.

Claims

1. A coil forming apparatus for manufacturing coils of a stator of a rotary electric machine having a predetermined number of stator slots comprising:

a twisting formation unit for twist-forming a predetermined number of U-shaped conductor segments each of which has a pair of parallelly extending straight portions and a turn portion connecting the straight portion, said twisting formation unit including a first twisting formation jig composed of a first inside ring and a first outside ring and a second twisting formation jig composed of a second inside ring and a second outside ring, wherein;

each of said first and second inside rings has the same predetermined number of circumferentially disposed holding slots as the stator slots to hold one of each pair of straight portions;

each of said first and second outside rings has the same number of circumferentially disposed holding slots as the stator slots to hold the other of each pair of straight portions; and

said first and second inside rings and said first and second outside rings are coaxially coupled to shift relative circumferential position between said inside rings and said outside rings by a predetermined angle to twist the turn portions.

2. The coil forming apparatus as claimed in claim 1, wherein at least one of said first and second twisting formation jigs twists pairs of U-shaped conductor segments that have different sized turn portions.

3. The coil forming apparatus as claimed in claim 1, wherein:

said twisting formation unit includes knocking bars for discharging the conductor segments from first and second twisting formation jigs; and

said first and second twisting formation jigs are movable relative to said knocking bars when discharging the conductor segments from said first and second twisting formation jigs.

4. The coil forming apparatus as claimed in claim 1, further comprising a compressing formation unit for radially compressing the U-shaped conductor segment that are twist-formed by said twisting formation unit in radially inward directions.

5. The coil forming apparatus as claimed in claim 4, wherein said compressing formation unit comprises:

a metal core having a cylindrical outer periphery for setting a diameter of an inscribed circle of the conductor segments;

a plurality of guiding arrow members respectively disposed in radial directions at equal intervals to form guide spaces between said guiding arrow members;

a plurality of thrusting arrow members respectively disposed in the guide spaces to compress the conductor members in radially inner directions when straight portions of the conductor segments are disposed in the guide spaces;

means for radially moving said thrusting arrow members, said means providing a cylindrical space for accommodating straight portions of the conductor segments around the cylindrical outer periphery of said metal core when moving said thrusting arrow members radially outward.

6. The coil forming apparatus as claimed in claim 5, wherein said means for radially moving comprises spring members each of which is disposed between one of said thrusting arrow members and one of said guiding arrow members.

7. The coil forming apparatus as claimed in claim 5, wherein:

said compressing formation unit is disposed above said twisting formation unit to move down relative to said twisting formation unit to send the straight portions of the conductor segments to the cylindrical space from the guide spaces after the U-shaped conductor segments are twist-formed by said twisting formation unit.

8. A method of forming coils of a stator of a rotary electric machine having a predetermined number of stator slots formed by the coil forming apparatus as claimed in claim 5 comprising:

a step of twist-forming all the straight portions by said first and second twisting formation units;

a step of discharging all the straight portions from said first and second twisting formation units;

a step of sending all the straight portions from said first and second twisting formation units to the guide spaces; and

a step of pushing all the straight portions into the cylindrical space and pushing at least a radially outside portion of the straight portions to radially inside portion thereof to be close to each other.