Systems and methods for improved gearboxes for evtol aircraft

Patent metadata

Field	Value
Publication number	US-2024253791-A1
Application number	US-202318391266-A
Country	US
Kind code	A1
Filing date	Dec 20, 2023
Priority date	Oct 6, 2022
Publication date	Aug 1, 2024
Grant date	—

Abstract

An electric engine for a vertical takeoff-and-landing aircraft comprising an electric motor assembly including a stator and a rotor. The electric engine may comprise an inverter assembly, a gearbox assembly including a sun gear, and a main shaft including a length of the main shaft that extends from a first end of the main shaft through the gearbox assembly and through the electric motor assembly to a second end of the main shaft. The electric engine may include a hydrodynamic bearing located between the main shaft and sun gear, and a bearing including an inner race mechanically coupled to the main shaft and an outer race mechanically coupled to the rotor. The electric engine may include a bearing including an outer race mechanically coupled to an inner surface of the rotor.

First claim

1 - 30 . (canceled)

31 . A method for balancing a rotor of an electrical engine of an electrical propulsion system comprising:
identifying an axis of rotation of a rotor, wherein the rotor comprises a sacrificial layer having a mass M formed along a circumference of the rotor; determining an imbalance present in the rotor by rotating the rotor about the axis of rotation, wherein determining an imbalance includes marking the rotor, rotating the rotor, and detecting an amplitude of the imbalance; calculating an amount of mass k to add or remove at a position p along the sacrificial layer such that a center of mass of the rotor coincides with the axis of rotation of the rotor; and removing an amount of mass r from the sacrificial layer such that an amount of remainder mass n is present along the circumference of the rotor.

32 . The method of claim 31 , wherein the amount of remainder mass n is equal to the amount of mass k.

33 . The method of claim 31 , further comprising a thickness of the sacrificial layer based on the precision of the machine machining the rotor.

34 . The method of claim 31 , wherein the rotor possesses a number of sacrificial layers greater than two.

35 . The method of claim 31 , wherein rotating the rotor about the axis of rotation includes rotating at a speed less than operating speed.

36 . The method of claim 31 , wherein rotating the rotor about the axis of rotation includes rotating at a speed less than the first resonance of the rotor.

37 . The method of claim 31 , wherein the remainder mass n is present at the position p when the amount of mass k is calculated to be added.

38 . The method of claim 31 , wherein the remainder mass n is present at a position q when the amount of mass k is calculated to be removed, wherein the position q is on the opposite side of the sacrificial layer from the position p.

39 . The method of claim 31 , wherein removing the amount of mass r includes an amount of mass equal to or less than M-k.

40 . The method of claim 31 , wherein detecting the amplitude of the imbalance may include using a machine to track the rotor mark during rotation and calculate the amplitude of the imbalance.

41 . The method of claim 40 , wherein the machine to track the rotor mark during rotation and calculate the amplitude of the imbalance may include an electric eye.

42 . The method of claim 40 , wherein the machine to track the rotor mark during rotation and calculate the amplitude of the imbalance may include an encoder.

43 . The method of claim 31 , wherein removing includes machining away.

44 . The method of claim 31 , wherein removing include using a machine with a milling resolution that is less than or equal to five microns.

45 . The method of claim 31 , wherein the rotor is made of aluminum.

46 . The method of claim 31 , wherein the sacrificial layer is made of aluminum.

47 . The method of claim 31 , further comprising a first end of the rotor and a second end of the rotor, wherein each end comprises a substantially circular profile, wherein a first sacrificial layer is posited a first distance from the first end of the rotor and a second sacrificial layer is posited a second distance from the second end of the rotor.

48 . The method of claim 47 , wherein the first sacrificial layer and the second sacrificial layer have substantially similar depths and widths.

49 . The method of claim 47 , wherein the first distance is substantially similar to the second distance.

50 . The method of claim 47 , wherein position p is located along either the first sacrificial layer or second sacrificial layer.

51 . The method of claim 31 , wherein the sacrificial layer includes N grooves defining N sacrificial portions, wherein the grooves are configured to guide oil flow through the rotor in normal operation.

52 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 50% of the volume of the sacrificial layer.

53 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 60% of the mass of the sacrificial layer.

54 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 70% of the mass of the sacrificial layer.

55 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 75% of the mass of the sacrificial layer.

56 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 80% of the mass of the sacrificial layer.

57 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 90% of the mass of the sacrificial layer.

58 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes removing at least 100% of the mass of the sacrificial layer.

59 . The method of claim 31 , wherein removing an amount of mass r from the sacrificial layer includes using a machine capable of removing less than 0.1% of the sacrificial layer material by volume.

60 . A method for balancing a rotor assembly of an electrical engine of an electrical propulsion system comprising:
identifying an axis of rotation of a rotor, wherein the rotor comprises a sacrificial layer having a mass M formed along a circumference of the rotor; determining a first imbalance present in the rotor by rotating the rotor about the axis of rotation, wherein determining the first imbalance includes marking the rotor, rotating the rotor, and detecting an amplitude of the imbalance; calculating an amount of mass k to add at a position p along the sacrificial layer such that a center of mass of the rotor coincides with the axis of rotation of the rotor; removing an amount of mass r from the sacrificial layer such that an amount of remainder mass n is present along the circumference of the rotor; identifying an axis of rotation of a rotor assembly, wherein the rotor assembly comprises the rotor mechanically coupled to a sun gear; determining a second imbalance present in the rotor assembly by rotating the rotor assembly about the axis of rotation, wherein determining the second imbalance includes marking the rotor assembly, rotating the rotor assembly, and detecting an amplitude of the imbalance; calculating a number j of rivets to add to the rotor assembly such that the center of mass of the rotor assembly coincides with the axis of rotation of the rotor assembly; and adding the j rivets to the rotor assembly.

Assignees

• Archer Aviation Inc

Inventors

• Graves Scott

Classifications

• B64D27/34

  All-electric aircraft · CPC title

• H02P27/08

  with pulse width modulation · CPC title

• H02P27/06

  using DC to AC converters or inverters (H02P27/05 takes precedence) · CPC title

• H02P25/16

  characterised by the circuit arrangement or by the kind of wiring · CPC title

• H02M7/5395

  by pulse-width modulation · CPC title