Arrangement for locking slot wedges retaining electric windings

• US 4,149,101 A
• Filed: 05/12/1977
• Issued: 04/10/1979
• Est. Priority Date: 05/12/1977
• Status: Expired due to Term

• Current Assignee: Albert Z. Lesokhin, Evelina A. Daikhovskaya, Mikhail R. Semenov
• Original Assignee: Albert Z. Lesokhin, Evelina A. Daikhovskaya, Mikhail R. Semenov
• Inventors: Daikhovskaya, Evelina A., Lesokhin, Albert Z., Semenov, Mikhail R.
• Primary Examiner(s): Skudy, R.
• Application Number:
  US05/796,065
• Time in Patent Office: 698 Days
• Field of Search: 310/214, 310/52, 310/215, 310/58, 310/194, 310/43, 310/192, 310/59, 310/65, 336/196, 336/197
• US Class Current: 310/214
• CPC Class Codes: H02K 3/487 Slot-closing devices
• CPC Class Codes: Y10S 174/19 in a dynamo-electric machine

Abstract

An arrangement for locking slot wedges retaining the winding of an electric machine against displacement thereof within the longitudinal slots of the magnetic core. The locking arrangement is disposed in the end portions of the slot and comprises locking wedges in contact with the extreme slot wedges and the locking wedges have teeth on the surfaces parallel to the bottom of the longitudinal slot. Stop collars are disposed at the intersection of the longitudinal slots and extreme radial ventilating ducts and embrace the locking wedges within a tooth portion thereof. Each tooth is defined by an inclined surface facing the central portion of the longitudinal slot from the ends thereof and a surface perpendicular to the axis of the core. The stop collars are shaped congruent to the locking wedge within a tooth portion thereof and are spaced from the lateral sides thereof. One end face of the stop collar is in contact with the surface of the tooth formed by a plane perpendicular to the core axis, while the other end face of the stop collar bears against the surface of the radial ventilating duct. Such a construction permits movement of the locking wedge only toward the central portion of the core, thus locking the slot wedges securely in place and preventing them from coming out of the longitudinal core slot.

Claims

1. In an magnetic core of an electric machine, having longitudinal slots arranged around the periphery thereof and provided with longitudinal grooves on the side walls near the top of the slots, said slots including a winding disposed therein, a plurality of radial ventilating ducts extending across said longitudinal slots, a plurality of slot wedges located end-to-end in the top portions of said longitudinal slots above said winding to retain said winding from displacement within said slots, and an arrangement for locking said slots wedges, disposed in the end portions of each of said longitudinal slots;

said arrangement comprising;

locking wedges disposed in said longitudinal slot and contacting the extreme slot wedges and having lugs on the side portions thereof, engaging said grooves of said longitudinal slot, and teeth on the surfaces parallel to the bottom of said longitudinal slots, defined by an inclined plane facing the central portion of said longitudinal slot from the ends thereof, and a plane perpendicular to the axis of said core;

stop collars, disposed at the points of the intersection of said longitudinal slots and the extreme radial ventilating ducts, embracing said locking wedges, said stop collars shaped congruent to said locking wedge within a tooth portion thereof, the portions of said stop collars facing the winding being in tight contact with the mating portions of said locking wedge and the inner side portions of said stop collar being spaced from the lateral sides of said locking wedge with side clearances formed therebetween, said side clearances enabling said locking wedge to be urged in said longitudinal slot along said grooves toward the central portion of said longitudinal slot from the ends thereof, one end face of said stop collar contacting the surface of said tooth of said locking wedge, defined by the plane perpendicular to the axis of said core, and the other end face of said stop collar bearing against the surface of said extreme radial ventilating ducts;

whereby said slot wedges are prevented from any axial displacement in said longitudinal slots.

2. An arrangement for locking said slot wedges according to claim 1, wherein said teeth are formed on the outer side of said locking wedge.

3. An arrangement for locking said slot wedges according to claim 1, wherein said teeth are formed both on the outer and inner sides of said locking wedge.

4. An arrangement for locking said slot wedges according to claim 1, wherein said stop collars are of resilient material.

5. An arrangement for locking said slot wedges according to claim 2, wherein said stop collars are of resilient material.

6. An arrangement for locking said slot wedges according to claim 3, wherein said stop collars are of resilient material.

7. An arrangement for locking said slot wedges according to claim 1, wherein said side clearances between said stop collars and said locking wedges range between about 2 mm to 6 mm.

8. An arrangement for locking said slot wedges according to claim 2, wherein said stop collar has an average height in cross-section of about 8 mm-15 mm.

9. An arrangement for locking said slot wedges according to claim 1, wherein said locking wedges are made from a thermosetting fibrous compound comprising a modified phenolformaldehyde resin binder with a filler selected from the group consisting of glass or glass thread.