Coil end cooling structure and manufacturing method of a stator

Patent metadata

Field	Value
Publication number	US-2026100618-A1
Application number	US-202519337368-A
Country	US
Kind code	A1
Filing date	Sep 23, 2025
Priority date	Oct 4, 2024
Publication date	Apr 9, 2026
Grant date	—

Abstract

A coil end cooling structure includes an insulator, and first and second covers. The insulator has first and second protrusions provided on respective end surfaces of a stator core of a stator in the axial direction, and a link to link the protrusions. The first and second covers are secured to the insulator and cover the coil end on the respective end surfaces of the stator. The link is provided along an inner wall of the slot. The first and second covers are provided with a supply port and a discharge port for a coolant that cools a stator coil provided in a slot of the stator core. The supply port is provided on a lower side in a direction of gravity, and the discharge port is provided on an upper side in the direction of gravity.

First claim

1 . A coil end cooling structure configured to cool a stator including a cylindrical stator core and a stator coil provided in a slot of the stator core and having a coil end protruding from an end surface in an axial direction of the stator core, the coil end cooling structure comprising:
an insulator including a first protrusion provided on one end surface of the stator core in the axial direction, a second protrusion provided on the other end surface, and a link configured to link the first protrusion and the second protrusion; and a first cover secured to the insulator and configured to cover the coil end on the one end surface of the stator, and a second cover configured to cover the coil end on the other end surface of the stator, wherein the link of the insulator is provided along an inner wall of the slot, wherein the first cover and the second cover are provided with a supply port for a coolant to cool the stator coil and a discharge port for the coolant, and wherein the supply port is provided on a lower side in a direction of gravity, and the discharge port is provided on an upper side in the direction of gravity.

2 . The coil end cooling structure according to claim 1 ,
wherein the first protrusion and the second protrusion of the insulator are each provided with an annular outer peripheral protrusion and an annular inner peripheral protrusion, and a radial protrusion linked to the outer peripheral protrusion and the inner peripheral protrusion, and wherein the radial protrusion is provided with a curved surface corresponding to a bending shape of each segment coil of the stator coil.

3 . The coil end cooling structure according to claim 2 , further comprising
a connector configured to couple a power line provided on the stator core to an external device, wherein the connector includes:
a mating portion configured to mate with an end of the power line in a space defined by the insulator and the first cover; and
a base on which the mating portion is provided,
wherein the base is configured to mate with a mounting opening formed in the first cover via a sealing member.

4 . The coil end cooling structure according to claim 3 ,
wherein the insulator is made of thermosetting resin, wherein the outer peripheral protrusion and the inner peripheral protrusion of each of the first protrusion and the second protrusion of the insulator are each provided with a notch along a circumferential direction, and wherein the first cover and the second cover are secured to the insulator by thermal caulking at the notch.

5 . A manufacturing method of a stator, comprising:
forming an insulator including a first protrusion provided on one end surface in an axial direction of a cylindrical stator core provided with slots, a second protrusion provided on the other end surface of the stator core, and a link provided along an inner wall of the slots and configured to link the first protrusion and the second protrusion; inserting segment coils into the slots of the stator core; twisting the segment coils along curved surfaces provided on the first protrusion and the second protrusion of the insulator to form a stator coil; securing the stator coil to the insulator; and securing a first cover to the first protrusion, the first cover configured to cover a coil end of the stator coil protruding from the stator core and the insulator on the one end surface of the stator core, and securing a second cover to the second protrusion, the second cover configured to cover a coil end of the stator coil protruding from the stator core and the insulator on the other end surface of the stator core.

Assignees

• Subaru Corp

Inventors

• Nagase Kimihiro

Classifications

• H02K9/19

  for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil · CPC title

• H02K15/36

  Processes or apparatus for simultaneously twisting two or more open ends of hairpins after their insertion into the machine (for simultaneously twisting two or more hairpins prior to mounting into the machine H02K15/0428) · CPC title

• H02K15/148

  Insulating casings or enclosures (H02K15/123 takes precedence) · CPC title

• B60K11/02

  with liquid cooling · CPC title

• H02K5/225

  Terminal boxes or connection arrangements (specially adapted for submersible motors H02K5/132) · CPC title