US3714920A

US3714920A - Marine propulsion unit

Info

Publication number: US3714920A
Application number: US00127883A
Authority: US
Inventors: E Setterblade
Original assignee: Avco Corp
Current assignee: Avco Corp
Priority date: 1971-03-25
Filing date: 1971-03-25
Publication date: 1973-02-06
Anticipated expiration: 1990-02-06

Abstract

THE DISCLOSURE ILLUSTRATES A MARINE PROPULSION UNIT IN WHICH A GAS TURBINE ENGINE HAVING A ROTATABLE OUTPUT SHAFT IS VERTICALLY MOUNTED ON A PAIR OF TRUNNIONS SECURED TO A VESSEL. A PROPELLER HOUSING IS PIVOTALLY MOUNTED ADJACENT THE OUTPUT SHAFT AND HAS A PROPELLER DRIVEN BY THE OUTPUT SHAFT. AN ACTUATOR PIVOTS THE PROPELLER HOUSING RELATIVE TO THE ENGINE HOUSING TO DIRECT THE THRUST PRODUCED BY THE PROPELLER.

Description

1973 E. o. SETTERBLADE 3,71

MARINE PROPULSION UNIT Filed March 25, 1971 R K fl-IZ 44 38 2* 3% 36 7 e2. POWER 120 u 64 LEVER -46 I CONTROL 35 10 I FUEL l 28 58 54 TANK 56 i l 30 26 u4 42 74 (IQ/ ACTUATOR l 4 72 6 |24 HYDRAULIC 18' J CONTROL SYSTEM 7688 mus 82 I08 o us H2 o o 98 I04 I INVENTOR.

EARL O. SETTERBLADE ATTOR NEYS United States Patent ABSTRACT OF THE DISCLOSURE The disclosure illustrates a marine propulsion unit in which a gas turbine engine having a rotatable output shaft is vertically mounted on a pair of trunnions secured to a vessel. A propeller housing is pivotally mounted adjacent the output shaft and has a propeller driven by the output shaft. An actuator pivots the propeller housing relative to the engine housing to direct the thrust produced by the propeller.

The present invention relates to propulsion systems and more particularly to marine propulsion systems.

The invention comprises a marine propulsion unit in which a gas turbine engine is nonrotatably connected to a vessel in a vertical orientation. An output shaft of the engine is connected to a propeller housing rotatably secured to the engine and having a propeller driven by the engine output shaft. An actuating means on the vessel pivots the propeller assembly thereby orienting the thrust of the propeller.

The above and other related features of the present invention will be apparent from a reading of the description of the disclosure shown in the accompanying drawing and the novelty thereof pointed out in the appended claims.

The single drawing illustrates a longitudinal section view of a marine propulsion system embodying the present invention and a vessel with which it may be used.

Referring now to the drawing, there is shown a marine propulsion unit, enclosed in removable housing 10, for use with a vessel, generally indicated by reference character 12. A support housing 14 has a pair of webs 16 (only one of which is shown) with vertically oriented openings 18 adapted to be removably telescoped over trunnions 20. Trunnions 20 are vertically extended from a structural plate 22 secured to the transom 24 of the vessel 12. Nuts 26 are threaded onto the upper portion of trunnions 20 to hold the webs 16 in place.

Housing .14 has a suitable inlet 28 which generally separates water from the air that enters the unit. From there the air passes through a series of passageways 30 formed in the housing 14 to the inlet end of an engine housing 32 solely supported by the housing 14. A bladed compressor rotor 34 is suitably journaled in housing 32. As rotor 34 rotates it pressurizes air entering from inlet 30 for discharge through diffuser 34 to a peforated combustor 32. Air that enters combustor 36 is mixed with fuel injected by nozzles 38 and ignited to produce a propulsive gas stream.

Nozzles 38 receive fuel via a nozzle supply conduit 40 extending to a fuel control unit 42. Fuel control 42 meters flow to the nozzles 38 in accordance with control signal inputs from an operator control lever 44 on a power lever control 46 in vessel 12. As herein illustrated, power lever control 44 is adapted to produce electrical signals which are transmitted via cables 48 through a quick disconnect connector 50 adjacent the propulsion unit to the fuel control 42. Fuel control 42 receives a suitable supply of fuel via flexible conduit 54 which extends to a fuel tank 56 "ice in vessel 12. Conduit '54 has a quick disconnect coupling 58 between the propulsion unit 10 and the vessel 12.

The propulsive gas stream generated in the combustor 36 is discharged through a turbine inlet duct 60 and passes across a first bladed turbine motor 62 interconnected with compressor rotor 34 by a shaft 62. From there the hot gas stream passes across a second bladed power turbine rotor 66 suitably journaled in engine housing 32 and then to an exhaust duct 68.

Bladed turbine rotor 66 is connected to a power output shaft 70 which is coaxial with and extends downward through shaft 64. Shaft 70 has a sun gear 72 positioned in housing 14 which drives a series of gears 74 also engaging a ring gear 76. The rotational rate of ring gear 76 is greatly reduced so that engine output shaft 78, extending from ring gear 76, rotates at a relatively low speed. Engine output shaft 78 is suitably journaled in a sleevelike extension '80 of housing 14 by bearings 82.

A propeller housing 84 is pivotally mounted to housing 14 by spaced

bearings

86 and 88 which have their inner race secured to extension and their outer race secured in the interior of housing 84. A suitable seal is provided around the periphery of the upper portion of propeller housing 84 to prevent leakage of water into the unit.

The propeller housing 84 has an input shaft 90 connected to the engine output shaft 78 through a splined connection 92 and journaled at its lower end by bearing assembly 94. A right angle gear

assembly comprising gears

96 and 98 enables the input shaft 90 to drive a propeller drive shaft 100 journaled by

bearings

102 and 104. A propeller 106 is mounted on the propeller output shaft and rotates to produce a thrust.

The propeller housing 84 is pivoted about a vertical axis through an arm 108 connected to the upper portion of housing 84. Arm 108 is connected to a rod 110 extending to a hydraulic actuator 112 suitably mounted within vessel 12. An actuator hydraulic control system 114 delivers pressurized fluid to the actuator 112 alternately through conduits 1'16 and 118. The selective pressurization extends or retracts rod 110 in response to inputs from an operator controlled steering wheel connected to the actuator hydraulic control system 114. The actuator hydraulic control system is adapted to receive a mechanical feedback from rod 110 via arm 122 and rod 124 so that the actuating force in one direction is automatically higher than the actuating [force in the opposite direction.

In operation, the gas turbine engine is maintained fixed relative to the vessel 12 while only the lower propeller housing 84 is swiveled to produce directional thrust. The torque reaction from the engine output shaft 78, tending to pivot propeller housing 84 in one direction, is automatically compensated for by the actuator hydraulic control system 114. This system produces a greater force when pivoting the housing 84 in opposition to the torque reaction and a lower force when pivoting it in the direction of the torque reaction. The vertical mount ing of the engine enables a highly compact unit that takes a minimum of space. It is apparent that since the engine is mounted outboard of the vessel its weight creates a moment arm tending to pitch the boat in an aft direction. However, this moment arm is minimized since the engine is vertically oriented with respect to the vessel. The trunnion mounting of the engine and the quick disconnect couplings enable rapid removal of the engine for replacement or servicing. However, since the engine housing 32 is solely supported from inlet housing 14, it may be conveniently serviced while the engine is in place.

While the preferred embodiment of the present invention has been described, it will be apparent to those skilled in the art that it may be modified Without departing from the spirit and scope thereof.

Having thus described the invention what is claimed as novel and desired to be secured by Letters Patent of the United States is:

- housinghas a structural web with an opening adapted to be removably telescoped over and secured on said trun- 1. A marine propulsion unit for a vessel, said propulsion nion. unit comprising: 3. A propulsion unit as in claim 2 wherein said engine a generally annular first housing; 5 comprises:

coaxial interconnected compressor and first turbine rotors journaled in said first housing and oriented to discharge a hot gas stream in an upward direction; a power turbine assembly including a second or power turbine rotor journaled in said first housing above a fuel control unit receiving a source of fuel for metered control to said propulsion unit, said fuel control also receiving an operator demand input signal;

means for removably coupling said fuel control to a said interconnected first turbine and compressor source of fuel on said vessel; and rotors and driven by said hot gas stream; means for removably coupling said fuel control to an a second housing adjacent the inlet end of said comoperator demand signal generating device on said pressor and secured to said first housing and formvessel. ing the inlet for air entering said compressor, said 4. A propulsion unit as in claim 1 wherein: second housing forming a nonrotatable connection said second housing has a sleevelike extension coaxial to said vessel and substantially the entire strucwith said output shaft; tural support for said first housing; I said output shaft is joumaled within said sleevelike a shaft extending from said power turbine rotor through extension; and

said interconnected compressor and turbine rotors said propeller housing is journaled around said sleeveto said second housing and a speed-reducing gear like extension. train in said second housing connected to said power turbine shaft and having an output shaft; References cued a propeller housing rotatably secured to said segond UNITED STATES PATENTS housing about an axis coaxial with said output s aft, an input shaft coaxial with the output shaft of said 638,542 12/1899 Atwood 11535 engine, and a propeller journaled for rotation on 2,384,436 9/ 1945 B055 said housing about an axis substantially at right 2,619,797 12/1952 Haworth angles to and driven by said input shaft; and 2,629,982 3/1953 HOOkeI actuating means on said vessel for pivoting said propeller housing thereby orienting the thrust of said propeller.

2. A propulsion unit as in claim 1 in combination with a vessel having at least one vertically oriented trunnion structurally supported by it and wherein said second MILTON BUCHLER, Primary 'Examiner E. R. KAZENSKE, Assistant Examiner U .8. Cl. X.R. 35 -17