Tilter motor cooling apparatus for vertical takeoff and landing aircraft and operating method of the same

Patent metadata

Field	Value
Publication number	US-11679872-B1
Application number	US-202218064538-A
Country	US
Kind code	B1
Filing date	Dec 12, 2022
Priority date	Dec 12, 2022
Publication date	Jun 20, 2023
Grant date	Jun 20, 2023

Abstract

A VTOL aircraft includes a plurality of tilt propellers configured to be rotated between a forward cruise configuration and a vertical lift configuration. A nacelle or other structure may be configured to form a low pressure zone from the wake of the tilt propellers when operating in the lift configuration. The low pressure zone may include an outlet side of a cooling path. Due to the low pressure, airflow may be induced through the cooling path even in the absence of strong air pressure at the inlet side. During a cruise operation when the VTOL aircraft is in forward motion, the nacelle or other structure may be aligned with a baffle to form an exhaust channel for the cooling airflow.

First claim

The invention claimed is:

1. A tilt apparatus of a vertical takeoff and landing (VTOL) craft, comprising:
a boom;
a propeller configured to be tiltable with respect to the boom between a lift configuration and a cruise configuration;
a motor assembly coupled to the propeller;
a nacelle connected to the motor assembly and configured to be tiltable with the propeller between the lift configuration and the cruise configuration; and
a thermal transfer device configured to thermally couple to the motor assembly, the thermal transfer device comprising an air outlet;
the nacelle comprising an air inlet and an extending portion configured to extend from the air outlet; and
a baffle attached to the boom and extending beyond a front surface of the boom, such that a leading edge of the baffle is forward of a trailing edge of the extending portion when the nacelle is in the cruise configuration,
wherein the air inlet is configured to receive a portion of a propwash from the propeller when the propeller is operated in the lift configuration.

2. The tilt apparatus of claim 1 , wherein the air inlet is configured as a cut-out in the nacelle.

3. The tilt apparatus of claim 1 ,
wherein the extending portion and the baffle are configured to overlap to form upper and lower surfaces of an exhaust channel from the air outlet to an exhaust outlet when the propeller is operating in the cruise configuration.

4. The tilt apparatus of claim 3 , wherein the extending portion and the baffle are configured to form the exhaust channel by tilting of the nacelle from the lift configuration to the cruise configuration.

5. The tilt apparatus of claim 3 , wherein:
the nacelle is movably mounted to a first portion of the boom; and
the baffle is mounted in a fixed position to a second portion of the boom.

6. The tilt apparatus of claim 3 , wherein the baffle and the extending portion are separated in the lift configuration so that the exhaust channel is not formed in the lift configuration.

7. The tilt apparatus of claim 3 , wherein an area of a wake region in the lift configuration is greater than an area of the exhaust channel in the cruise configuration.

8. The tilt apparatus of claim 3 , wherein the exhaust outlet is configured to exhaust air from the air outlet to an exterior of the tilt apparatus, the exhaust outlet being formed from the extending portion and the baffle.

9. The tilt apparatus of claim 1 , wherein the extending portion forms an extended negative pressure zone at the air outlet when the propeller is operated in the lift configuration.

10. The tilt apparatus of claim 1 , wherein the extending portion extends at least four inches from the air outlet.

11. The tilt apparatus of claim 1 , wherein the extending portion extends not more than 24 inches from the air outlet.

12. The tilt apparatus of claim 1 , wherein the extending portion comprises an arc length of at least 45 degrees around a rotational axis of the propeller.

13. The tilt apparatus of claim 1 , wherein the extending portion comprises an arc length of not more than 270 degrees around a rotational axis of the propeller.

14. The tilt apparatus of claim 1 , wherein the air outlet is configured to be in a low pressure zone created by a further portion of the propwash passing along an outside of the nacelle.

15. The tilt apparatus of claim 1 , wherein the propeller propwash creates a negative pressure zone at the air outlet relative to the air inlet.

16. The tilt apparatus of claim 1 , wherein the thermal transfer device comprises a heat exchanger.

17. The tilt apparatus of claim 1 , wherein the air inlet is configured to face the propeller.

18. The tilt apparatus of claim 1 , wherein the air inlet is located within 25% of a propeller radius.

19. The tilt apparatus of claim 1 , wherein an open air volume at the air outlet is greater in the lift configuration than in the cruise configuration.

20. The tilt apparatus of claim 1 , wherein the propeller is configured to direct air into the air inlet.

21. The tilt apparatus of claim 1 , wherein the air inlet is located at a lower side of the nacelle in the cruise configuration.

22. A method of operating a tilt apparatus of a vertical takeoff and landing (VTOL) craft, comprising:
tilting a nacelle and a propeller with respect to a boom into a lift configuration, the propeller being coupled to a motor assembly, the motor assembly being connected to the nacelle, the boom having an attached baffle extending beyond a front surface of the boom;
directing propwash from the tilt propeller to an air inlet of the nacelle and further to an air outlet of a thermal transfer device configured to thermally couple to the motor assembly, the nacelle comprising an extending portion configured to extend from the air outlet; and
tilting the nacelle and the propeller from the lift configuration to a cruise configuration such that a leading edge of the baffle is forward of a trailing edge of the extending portion when the nacelle is in the cruise configuration.

23. The method of claim 22 , further comprising:
forming an exhaust channel for the air outlet in the cruise configuration, the exhaust channel comprising the extending portion and the baffle; and
exhausting air from the air outlet via the exhaust channel.

24. The method of claim 23 , further comprising:
in the lift configuration, generating a negative pressure zone at the air outlet by directing a further propwash over an outside of the nacelle, the negative pressure zone causing air to flow from the air inlet to the air outlet.

25. The method of claim 23 , wherein the extending portion extends at least four inches from the air outlet.

26. The method of claim 23 , wherein the extending portion extends at least eight inches from the air outlet.

27. The method of claim 23 , wherein the extending portion extends at least twelve inches from the air outlet.

28. The method of claim 23 , wherein the extending portion extends not more than 24 inches from the air outlet.

29. The method of claim 23 , wherein:
the boom is mounted to a wing; and
the extending portion extends from the air outlet by not more than half a distance from the wing to a front of the boom.

30. The apparatus of claim 1 , wherein the apparatus is configured so that an air pressure at the air outlet is less than an air pressure at the air inlet when the propeller is operated in the lift configuration.

31. The tilt apparatus of claim 1 , wherein the extending portion extends at least eight inches from the air outlet.

32. The tilt apparatus of claim 1 , wherein the extending portion extends at least twelve inches from the air outlet.

33. The tilt apparatus of claim 1 , further comprising a wing, wherein:
the boom is mounted to the wing, and
the extending portion extends from the air outlet by not more than half a distance from the wing to a front of the boom.

Assignees

• Archer Aviation Inc

Inventors

• Tulsyan Bharat
• Heath Christopher M
• Manning Kerry
• Droandi Giovanni

Classifications

• B64C29/0033 Primary

  the propellers being tiltable relative to the fuselage · CPC title

• B64D33/08

  of power plant cooling systems · CPC title

• B64C29/0025

  the propellers being fixed relative to the fuselage · CPC title