Back to results
US 10,590,854 B2Granted
Geared gas turbine engine
AssigneeUnited Technologies Corporation
InventorWilliam G. Sheridan
Life of this patent
Estimating the term…
Abstract
A turboshaft engine includes a high speed spool that connects a high pressure compressor with a high pressure turbine. A low speed spool connects a low pressure compressor with a low pressure turbine. A speed change mechanism includes an input that is in communication with the low spool and a fixed gear ratio. An output turboshaft is in communication with an output of the speed change mechanism.
Claims20
A turboshaft engine comprising:
- a high speed spool connecting a high pressure centrifugal compressor with a high pressure turbine;
- a low speed spool connecting a low pressure compressor with a low pressure turbine, wherein the low speed spool rotates around a central turboshaft engine rotational axis;
- an epicyclic gear train including an input fixed to rotate with the low spool, wherein the epicyclic gear train is a star gear system and includes a carrier is fixed from rotation relative to an engine static structure with a flexible support and a fixed gear ratio of between 1.5 to 2.5;
- and
- an output turboshaft fixed to rotate with a ring gear of the epicyclic gear train, wherein the turboshaft engine includes a bypass ratio of zero, the output turboshaft rotates around a central output turboshaft rotational axis, the central output turboshaft rotational axis is centered and parallel with the central turboshaft engine rotational axis, and an outermost duct of the turboshaft engine is defined by a core airflow path.
2 more elements
A turboshaft engine comprising:
- a high speed spool connecting a high pressure centrifugal compressor with a high pressure turbine;
- a low speed spool connecting a low pressure compressor with a low pressure turbine, wherein the low speed spool rotates around a central turboshaft engine rotational axis;
- an epicyclic gear train including an input fixed to rotate with the low spool, wherein the epicyclic gear train is a planet gear system and includes a ring gear is fixed from rotation relative to an engine static structure with a flexible support and a fixed gear ratio of between 2.5 to 4.0;
- and
- an output turboshaft fixed to rotate with a carrier of the epicyclic gear train, wherein the turboshaft engine includes a bypass ratio of zero, the output turboshaft rotates around a central output turboshaft rotational axis, the central output turboshaft rotational axis is centered and parallel with the central turboshaft engine rotational axis, and an outermost duct of the turboshaft engine is defined by a core airflow path.
2 more elements
A method of operating a turboshaft engine comprising the steps of:
- rotating a high speed spool including a high pressure centrifugal compressor and a high pressure turbine at between 48,000 rpms and 50,000 rpms;
- rotating a low speed spool including a low pressure compressor and a low pressure turbine at 40,000 rpms around a central turboshaft engine rotational axis;
- reducing a rotational speed of the low speed spool by a ratio of 1.5 to 4.0 with an epicyclic gear train, wherein an input of the epicyclic gear train is attached to the low speed spool and the turboshaft engine includes a bypass ratio of zero;
- and
- rotating an output turboshaft fixed to rotate with an output of the epicyclic gear train at a reduced rotational speed relative to the input, wherein the output turboshaft rotates around a central output turboshaft rotational axis, the central output turboshaft rotational axis is centered and parallel with the central turboshaft engine rotational axis, and an outermost duct of the turboshaft engine is defined by a core airflow path.
2 more elements
Dependencies are inferred from the claim text.