Hybrid electric gas turbine engine two speed transmission for low spool drive power injection and power extraction

Patent metadata

Field	Value
Publication number	US-2025223925-A1
Application number	US-202418404185-A
Country	US
Kind code	A1
Filing date	Jan 4, 2024
Priority date	Jan 4, 2024
Publication date	Jul 10, 2025
Grant date	—

Abstract

A hybrid electric gas turbine engine two speed transmission for a low spool drive including an accessory gearbox in operative communication with a low speed spool motor-generator; a transmission in operative communication with the accessory gearbox and the low speed spool motor-generator; a low speed spool angled gearbox in operative communication with the transmission; and a low speed spool in operative communication with the low speed spool angled gearbox.

First claim

1 . A hybrid electric gas turbine engine two speed transmission for a low spool drive comprising:
an accessory gearbox in operative communication with a low speed spool motor-generator; a transmission in operative communication with the accessory gearbox and the low speed spool motor-generator, wherein the transmission comprises a two speed transmission configured for hybrid electric low spool drive applications; a low speed spool angled gearbox in operative communication with the transmission; and a low speed spool in operative communication with the low speed spool angled gearbox.

2 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 1 , wherein the accessory gearbox is in operative communication with an oil pump and a fuel pump.

3 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 1 , wherein the accessory gearbox is in operative communication with a first high speed spool motor-generator and a second high speed spool motor-generator.

4 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 1 , wherein the accessory gearbox is in operative communication with a high speed spool via a high speed spool angled gearbox.

5 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 1 , wherein the transmission and low speed spool angled gearbox are integrally formed sharing a common housing.

6 . (canceled)

7 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 1 , wherein the transmission is bolted to the accessory gearbox configured as a line removeable unit.

8 . A hybrid electric gas turbine engine two speed transmission for a low spool drive comprising:
an engine structure proximate a compressor of the gas turbine engine; a low speed spool towershaft coupled to the engine structure; a low speed spool angled gearbox in operative communication with the towershaft and in operative communication with a low speed spool of the gas turbine engine; a transmission in operative communication with the low speed spool angled gearbox, wherein the transmission comprises a two speed transmission configured for hybrid electric low spool drive applications; an accessory gearbox in operative communication with the transmission; and a low speed spool motor-generator in operative communication with the accessory gearbox.

9 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 8 , wherein the transmission is bolted to the accessory gearbox configured as a line removeable unit.

10 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 8 , wherein the transmission and low speed spool angled gearbox are integrally formed sharing a common housing.

11 . (canceled)

12 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 8 , wherein the accessory gearbox is in operative communication with a first high speed spool motor-generator and a second high speed spool motor-generator.

13 . The hybrid electric gas turbine engine two speed transmission for a low spool drive according to claim 8 , wherein the accessory gearbox is in operative communication with a high speed spool via a high speed spool angled gearbox.

14 . A process for a hybrid electric gas turbine engine two speed transmission for a low spool drive comprising:
providing an engine structure proximate a compressor of the gas turbine engine; coupling a low speed spool towershaft to the engine structure; coupling a low speed spool angled gearbox in operative communication with the towershaft; coupling the low speed spool angled gearbox in operative communication with a low speed spool of the gas turbine engine; coupling a transmission in operative communication with the low speed spool angled gearbox, configuring the transmission as a two speed transmission configured for hybrid electric low spool drive applications; coupling an accessory gearbox in operative communication with the transmission; and coupling a low speed spool motor-generator in operative communication with the accessory gearbox.

15 . The process of claim 14 , further comprising:
integrally forming the transmission and low speed spool angled gearbox sharing a common housing.

16 . (canceled)

17 . The process of claim 16 , further comprising:
configuring the two-speed transmission for two operational modes.

18 . The process of claim 14 , wherein the two operational modes comprise:
a first operational MODE 1 configured as a direct drive to the low spool motor-generator for high speed operation of the low speed spool; and a second operational MODE 2 configured to provide up to a 3× increase in motor shaft speed wherein the transmission includes a gear ratio of 3.0 which increases motor speed for low speed spool operation selected from the group comprising a ground idle speed and a flight idle speed.

19 . The process of claim 14 , further comprising:
configuring the transmission for a low spool drive power extraction wherein the low spool drive power extraction is arranged for A/C loads and battery recharge.

20 . The process of claim 14 , further comprising:
configuring the transmission for a low spool drive power injection on ground.

Assignees

• Rtx Corp

Inventors

• Clark Thomas E
• Hanrahan Paul R
• Breault Andrew E

Classifications

• F16H2200/0034

  the gear ratios comprising two forward speeds · CPC title

• F16H2057/02082

  for application in vehicles other than propelling, e.g. adjustment of parts · CPC title

• F16H2057/02034

  Gearboxes combined or connected with electric machines · CPC title

• F16H2057/02013

  Extension units for gearboxes, e.g. additional units attached to a main gear · CPC title

• F16H57/038

  Gearboxes for accommodating bevel gears (F16H57/037 takes precedence) · CPC title