Rotary electrical machine

Patent metadata

Field	Value
Publication number	US-2024097525-A1
Application number	US-202218289410-A
Country	US
Kind code	A1
Filing date	May 17, 2022
Priority date	Jun 4, 2021
Publication date	Mar 21, 2024
Grant date	—

Abstract

A stator of a rotary electrical machine includes a stator core, a coil, and at least one of a connection wire and a jumper wire. The coil has a first coil end which is located on one end side of the stator core in the axial direction and a second coil end which is located on the other end side of the stator core in the axial direction. A coolant flow path for cooling the rotor and the stator has: a coolant inflow port; a first annular flow path which faces an air gap in the axial direction; a relay flow path which is provided on the second coil end side and which faces the air gap in the axial direction; and a second annular flow path which is in communication with the relay flow path and which is provided as shifted radially outward with respect to the air gap.

First claim

1 . A rotary electrical machine comprising:
a rotor; a stator facing the rotor via a predetermined air gap; and a flow channel through which a refrigerant for cooling the rotor and the stator flows, wherein the stator has a stator core having a plurality of slots in a circumferential direction, a plurality of coils arranged in the slots in the circumferential direction of the stator core, and at least one of a connection wire connecting an external device and the coils and a jumper wire connecting the coils adjacent to each other in the circumferential direction, the coils have a first coil end projecting from the slot on one end side in an axial direction of the stator core and a second coil end projecting from the slot on the other end side of the stator core in the axial direction, the flow channel has a refrigerant inflow port disposed on a side of the first coil end, a first annular flow channel that extends in the circumferential direction in communication with the refrigerant inflow port and faces the air gap in an axial direction, a relay flow channel that is disposed on a side of the second coil end and faces the air gap in the axial direction, and a second annular flow channel that extends in the circumferential direction in communication with the relay flow channel and is disposed to be shifted outward in a radial direction with respect to the air gap, and the connection wire or the jumper wire included in the coil is disposed in the first annular flow channel.

2 . The rotary electrical machine according to claim 1 , wherein
the coil includes both the connection wire and the jumper wire, and the connection wire and the jumper wire are disposed in the first annular flow channel.

3 . The rotary electrical machine according to claim 1 , wherein the refrigerant flows through the flow channel in order of the refrigerant inflow port, the first annular flow channel, the air gap, the relay flow channel, and the second annular flow channel to cool the rotor and the stator.

4 . The rotary electrical machine according to claim 1 , wherein the first annular flow channel and the relay flow channel face the air gap in the axial direction on an entire circumference of the air gap and are connected to the air gap.

5 . The rotary electrical machine according to claim 1 , further comprising a baffle plate configured to deflect a flow of the refrigerant in the circumferential direction at an outlet portion of the refrigerant inflow port to the first annular flow channel.

6 . The rotary electrical machine according to claim 1 , wherein a plurality of the refrigerant inflow ports are arranged in the circumferential direction.

7 . The rotary electrical machine according to claim 1 , further comprising a cooling jacket which encloses the stator on an outer circumference of the stator and in which a refrigerant flow channel is formed.

8 . The rotary electrical machine according to claim 7 , wherein
a refrigerant inlet to the second annular flow channel is provided at one location in the circumferential direction, an inlet of a refrigerant flow channel formed in the cooling jacket is provided on a radially opposite side of the refrigerant inlet to the second annular flow channel with a rotary shaft of the rotor interposed between the inlet and the refrigerant inlet, and a flow channel is formed to allow a refrigerant that has flowed into the second annular flow channel to flow halfway through the second annular flow channel in the circumferential direction, then flow from the inlet into the refrigerant flow channel of the cooling jacket, and flow outside the rotary electrical machine after flowing halfway through the refrigerant flow channel of the cooling jacket in the circumferential direction.

9 . An electric wheel that has a wheel, a power converter, and a rotary electrical machine including a stator and a rotor, in which the stator is provided on a side of the wheel or a side of a suspension device that attaches the electric wheel to a vehicle body frame, the electric wheel comprising as the rotary electrical machine, the rotary electrical machine according to claim 1 .

Assignees

• Hitachi Ltd

Inventors

• IWANO Ryuuichirou
• Suto Tetsuya

Classifications

• H02K1/14

  Stator cores with salient poles · CPC title

• H02K3/24

  with channels or ducts for cooling medium between the conductors · CPC title

• H02K5/203 Primary

  specially adapted for liquids, e.g. cooling jackets · CPC title

• H02K9/19

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

• Y02T10/64

  Electric machine technologies in electromobility · CPC title