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EP-4165753-B1 - AIR FLOW CONTROL APPARATUS

EP4165753B1EP 4165753 B1EP4165753 B1EP 4165753B1EP-4165753-B1

Inventors

  • SORO JUAN, Enric
  • CESA, Tiago
  • MICHAELIDES, Alexandros
  • GOPAL, Madhavan

Dates

Publication Date
20260513
Application Date
20210611

Claims (13)

  1. A rotor end member (20-1, 20-2) for conveying air through a rotor (6) of an electric machine (1), the rotor end member (20-1, 20-2) comprising: at least one air inlet aperture (23-n) for conveyance of air into one or more first rotor aperture (12-n) formed in a radially inner section (RE1) of the rotor (6); at least one air outlet aperture (30-n) for discharging air from one or more second rotor aperture (13A-C) formed in a radially outer section (RE2) of the rotor (6); characterized in that the rotor end member (20-1, 20-2) comprises one or both of: at least one first flow guide (26-1) for directing air into the or each air inlet aperture (23-n), the first flow guide (26-1) comprising a first guide surface facing in a first circumferential direction and oriented at an acute angle relative to a longitudinal axis of the air inlet aperture (23-n), and at least one second flow guide (27-1) for drawing air into the or each air inlet aperture (23-n), the second flow guide (27-1) comprising a second guide surface facing in a second circumferential direction and oriented at an acute angle relative to a longitudinal axis of the air inlet aperture(23-n).
  2. A rotor end member (20-1, 20-2) as claimed in any one of the preceding claims, wherein the or each inlet aperture (23-n) is formed in a recessed section of the rotor end member (20-1, 20-2).
  3. A rotor end member (20-1, 20-2) as claimed in any one of the preceding claims comprising an annular wall (32) disposed between the at least one air inlet aperture (23-n) and the at least one air outlet aperture (30-n).
  4. A rotor end member (20-1, 20-2) as claimed in any one of the preceding claims, wherein the at least one air outlet (30-n) aperture is disposed radially outwardly of the at least one air inlet aperture (23-n).
  5. A rotor end member (20-1, 20-2) as claimed in any one of the preceding claims comprising at least one low pressure generator (31-n) for drawing air through the at least one air outlet aperture (30-n).
  6. A rotor end member (20-1, 20-2) as claimed in claim 5, wherein the or each low pressure generator (31-n) comprises a projection extending outwardly in a radial direction.
  7. A rotor assembly for an electric machine, the rotor assembly comprising a rotor (6) and at least one rotor end member (20-1, 20-2) as claimed in any one of the preceding claims; wherein the rotor (6) comprises at least one first rotor aperture (12-n) and at least one second rotor aperture (13A-C).
  8. A rotor assembly (3) as claimed in claim 7, wherein the rotor (6) comprises at least one fluid communication channel (19; 35) for establishing fluid communication between the or each first rotor aperture (12) and the or each second rotor aperture (13A-C).
  9. A rotor assembly (3) as claimed in claim 8, wherein the at least one fluid communication channel (19; 35) is formed by a centrifugal fan (7).
  10. A rotor assembly (3) as claimed in any one of claims 7, 8 or 9 comprising first and second rotor end members (20-1, 20-2) disposed at respective first and second ends of the rotor (6).
  11. A rotor assembly (3) as claimed in claims 8 and 10, wherein the at least one fluid communication channel (19; 35) is disposed between the first and second rotor end members (20-1, 20-2).
  12. An electric machine (1) comprising a rotor assembly (3) as claimed in any one of claims 7 to 11.
  13. A vehicle (V) comprising an electric machine (1) as claimed in claim 12.

Description

TECHNICAL FIELD The present disclosure relates to an air flow control apparatus. More particularly, but not exclusively, the present disclosure relates to air flow control apparatus for a rotor of an electric machine. Aspects of the invention relate to a rotor end member, a rotor assembly, an electric machine and a vehicle. BACKGROUND The cooling of a rotor of an electric motor can present particular challenges due to the rotation thereof. This may represent a limiting factor for the performance of the electric motor. It is an aim of the present invention to address one or more of the disadvantages associated with the prior art. Relevant prior art is disclosed in DE 10 2012 220239 A1 and DE 10 2013 214082 A1. SUMMARY OF THE INVENTION Aspects and embodiments of the invention provide a rotor end member, a rotor assembly, an electric machine and a vehicle as claimed in the appended claims. According to an aspect of the present invention there is provided a rotor end member for conveying air through a rotor of an electric machine, the rotor end member comprising: at least one air inlet aperture for conveyance of air into one or more first rotor aperture formed in a radially inner section of the rotor; andat least one air outlet aperture for discharging air from one or more second rotor aperture formed in a radially outer section of the rotor. The rotor end member may be configured to function as a compressor for introducing air into the rotor. The rotor end member may help to convey air from the side of the rotor towards the centre thereof. In use, the rotor end member conveys air into the first rotor aperture and discharges air from the second rotor aperture. The rotor end member may thereby promote air circulation through the rotor. For example, air may be circulated through the first and second rotor apertures. At least in certain embodiments, this may improve cooling of the rotor. The air may be circulated through the first and second rotor apertures in opposite directions. The rotor end member is configured to rotate with the rotor. The rotor end member may be mounted to the rotor and/or to a drive shaft of the electric machine. The rotor end member may comprise means for fixedly mounting the rotor end member to the rotor or the drive shaft. The at least one air outlet aperture may be configured to enable air to be discharged in an axial direction. The or each air inlet aperture comprising an inlet aperture central axis. The one or more first rotor aperture each comprising a longitudinal axis. The inlet aperture central axis may be inclined at an acute angle relative to the longitudinal axis of the corresponding first rotor aperture. The inlet aperture central axis may be oriented in a circumferential direction. The inlet aperture central axis may be oriented in a direction of rotation of the rotor end member. The rotor end member comprises at least one first flow guide for directing air into the or each inlet aperture. The first flow guide comprises a first guide surface facing in a first circumferential direction and oriented at an acute angle relative to a longitudinal axis of the air inlet aperture. The first guide surface may be configured to face towards the rotor. The first guide surface may be disposed at (or proximal to) a trailing edge of the air inlet aperture (with respect to a rotational direction of the rotor). The first circumferential direction may correspond to a rotational travel direction of the rotor end member. The first guide surface may form a converging surface for directing the air into the or each inlet aperture. The rotor end member comprises at least one second flow guide for drawing air into the or each inlet aperture. The second flow guide comprises a second guide surface facing in a second circumferential direction and oriented at an acute angle relative to a longitudinal axis of the air inlet aperture. The second guide surface may be configured to face away from the rotor. The second guide surface may be disposed at (or proximal to) a leading edge of the air inlet aperture (with respect to a rotational direction of the rotor). The second guide surface may form a diverging surface for drawing air into the or each inlet aperture. The first and second circumferential directions may be opposite to each other. The first second flow guides may be disposed on opposing sides of the or each inlet aperture. The or each inlet aperture may be formed in a recessed section of the rotor end member. The recessed section may comprise or consist of an annular recess. The rotor end member may have an annular wall disposed between the at least one air inlet aperture and the at least one air outlet aperture. The at least one air outlet aperture may be disposed radially outwardly of the at least one air inlet aperture. The rotor end member may comprise at least one low pressure generator for drawing air through the at least one air outlet aperture. The or each low pressure generator may comprise