US1831835A - Generator for motor boats or the like - Google Patents

Generator for motor boats or the like Download PDF

Info

Publication number
US1831835A
US1831835A US405227A US40522729A US1831835A US 1831835 A US1831835 A US 1831835A US 405227 A US405227 A US 405227A US 40522729 A US40522729 A US 40522729A US 1831835 A US1831835 A US 1831835A
Authority
US
United States
Prior art keywords
casing
water
generator
shaft
rear end
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US405227A
Inventor
Herbert D Allee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US405227A priority Critical patent/US1831835A/en
Application granted granted Critical
Publication of US1831835A publication Critical patent/US1831835A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K7/00Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/18Structural association of electric generators with mechanical driving motors, e.g. with turbines
    • H02K7/1807Rotary generators
    • H02K7/1823Rotary generators structurally associated with turbines or similar engines
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03BMACHINES OR ENGINES FOR LIQUIDS
    • F03B13/00Adaptations of machines or engines for special use; Combinations of machines or engines with driving or driven apparatus; Power stations or aggregates
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S416/00Fluid reaction surfaces, i.e. impellers
    • Y10S416/04Fluid current motor and generator

Definitions

  • This invention relates to electric generators and particularly to generators for boats and the like.
  • the main objects of this invention are to provide an electric generator particularly adapted for use on small boats in which the engine or other source of power is not adapted to directly drive a generator; to provide an-electric generator which may be readily attached to the hull of a boat below the water line and which is arranged so as to be driven by the water as the boat passes therethrough; to provide a hydroy electric generator in the form of a relatively small compact unit which will present little resistance to its passage through the water;
  • FIG. 1 is a view in side elevation of an outboard motor boat equipped with my improved hydro-electric generator, a portion of the boat being broken away to more clearly show the installation.
  • Fig. 2 is an enlarged Vertical, medial, longitudinal, sectional view of my generator mounted in a fragmentary portion of a boat hull.
  • Fig. 3 is a sectional View taken on the line 3 3 of Fig. 2, looking'in the direction indicated by the arrows.
  • the inner casing 5 has an axially extending space or bore 7 therein, open at the front end, and in which is mounted an assembly of field coils 8.
  • the rear end of the casing 5 terminates in spaced relation to the rear end of the outer casing 4, and is provided with an arma ture shaft bearing 9 and stuffing box 10.
  • a cap 11 ofogival shape is detachably secured to the front of the casings by screws 12,
  • the cap 11 carries anarmature shaft bearing or bushing 13 concentrically therein, in which is journaled the front end of an armature shaft 14, upon which is mounted an armature 15 within the field coils 8.
  • the opposite end of the armature shaft 14 is journaled in the bearing 9, and rojects rearwardly through the stuffing box 0.
  • Such projecting end is provided with an impeller 16 secured thereon by a nut 17.
  • impeller 16 is housed within the rear end of the outer casing 4 and a screen 18 is secured rearwardly thereof so as to protect the -impeller fromdama e.
  • mediately back of thenose cap 11 is provided with a plurality of water inlet ports 19, opening toward the side of the device rather than the front, which admit water to the annular passageway Q6 for acting on the impeller 16 .
  • Means are provided for attaching the device to the hull 20 of a boat and comprise a. radially extending shank 2l integrally formed with the outer casing.
  • the outer end of the shank is exteriorly threaded to receivey a nut 22 which is screwed down on a gasket 23 interposed between the nut and the inner side of the hull through which the shank projects.
  • This construction forms a simple and iicient means for securing the device to a oat.
  • Electric conductors 24 are provided in suitable passa eways which extend through the shank 21 or transmitting current collected by the brush 25 which rides on the commutator 26 of the generating unit. It will be noted that in this way the conductors 24 are protected against contact with the water or with foreign objects in the water.
  • a ⁇ hydro-electric generator comprising the screen 18.
  • a hydro-electric generator comprising aid the flow from this cause, but I prefer to an elongated tubular housing having water eliminate a material amount of flow by this intake ports adjacent the front end thereof method because of the greater possibility 'of and the rear end thereof permitting water clo 'ng the orts 19 by foreign matter.
  • an inner casin though xI) show a conventional form of housed within said outer casin and termistuliing box 10 for sealin the rear end of the nati-iig in spaced relation to te rear end armatureshaft 14, it wi be obvious that any thereof, an electric enerator unit sealed suitable form of sealing device may be emagainst the entrance o water thereinto withplo ed at this point.
  • a drive shaft for said orm'al changes may be made in the speunit having one end projecting into the s ace ciic embodiment of the invention described at the rear end of said inner casing, an an without de arting from thespirit and subimp stance of the broad invention, the scope of driving said unit, said impeller being housed 6.
  • a hydro-electric generator comprising an outer casing, an inner casing in spaced relation thereto providing a water passagegenerating unit within way therebetween, a current generating unit said casing, a drive shaft for said unit having housed within said inner casing, a drive shaft one end projecting through a stufling box in for said unit extending into the space proan impeller on said projecting' vided by said outer casing, and an impeller shaft end,'said casin havingawater passa 0n said shaft and housed within said outer wayleadingto Said impeller for rotatingt e casing for driving said generator, a shank )projecting from said outer casing for attachwater, a shank'on said casing for attaching.
  • a hydro-electric generator comprising conductor passing carryin current from said generating unit. ing llllit- 2.' A ydro-electric generator comprising 7.
  • a h dro-electric generator comprising an outer casing adapted to be attached tov a, elongate inner and outer casin in con- 'boat hull, an inner casing integrally attached centrically spaced relation to provide a water at its forward end to said outer casi and SSBgeWay therebetween; Said inner casing s111151 ataving an axially extending space open at the tachment, said outer casin having water front end thereof, field coils mounted within inletl ports communicating with the tween said casings, a current generating unit.
  • Astaging box at the rear end of said inner sealed from the entrance of water thereinto Casing a detachable cap for closing the front within said inner casing, a drive shaft for end of said space,.an armature shaft bearing said unit projecting through the rear end mounted in said cap, an armature shaft jourof said inner casing, andan impeller on said naled in said bearings with the rear end probox, an 'arma- 3.
  • A- hydro-electric generator comprisin an inner casing in spa an'impeller on said projecting v shaft end for 'providing a water passagerotating said armature, sai
  • a generator ⁇ for boats in combination, a hollow casing having a streamlined nose and an open rear end,'a water tight compartment within said casing spaced radiall i11- wardly from thel inner Walls the'eo an electric generator within said shaft project,
  • An electric power generating unit for boats comprising a generally cylindrical ho1 ⁇ low outer casing having a substantially pointed nose portion, a generating unit within said casing sealed. againstthe entrance of water and providing a water passage between it and said casing, said casing having water passages connecting said space with the exterior surface thereof at apoint removed from the extreme tip of said nose portion,- a drive shaft projectingfrom one end of said generating unit, and a propeller secured to said shaft within the protection of said casing and exposed to the How of water therethrough.
  • propeller secured to said shaft externally of said inner casing but internally of the outer of s ald casings, a nose portion for said outer casing, said outer casing being open at the rear end thereofand having intake openings ad] acent the forward end thereof exposed primarily on the side faces of said outer casing, and a screen mounted on said outer cas-r ing to protect said open rear end.

Description

Nov, 17,` 1931. H. D. ALLEE I 1,831,835
GENERATOR FOR MOTOR BOATS OR THE LIKE Filed Nov. e, 1929 lvl ATTORN EYS Patented Nov. 17, 1931 HERBERT D. ALLEE, OF SANDWICH, ONTARIO,
GENERATOR FOR MOTOR BOATS B. THE LIKE Application led November 6, 1929. Serial No. 405,227.
This invention relates to electric generators and particularly to generators for boats and the like.
The main objects of this invention are to provide an electric generator particularly adapted for use on small boats in which the engine or other source of power is not adapted to directly drive a generator; to provide an-electric generator which may be readily attached to the hull of a boat below the water line and which is arranged so as to be driven by the water as the boat passes therethrough; to provide a hydroy electric generator in the form of a relatively small compact unit which will present little resistance to its passage through the water;
and to provide such a device in which the generator driving -impeller is fully protected from injury or from entanglement with weeds and the like.
An illustrative embodiment of this invention is shown in the accompanying drawings, in which Fig. 1 is a view in side elevation of an outboard motor boat equipped with my improved hydro-electric generator, a portion of the boat being broken away to more clearly show the installation.
Fig. 2 is an enlarged Vertical, medial, longitudinal, sectional view of my generator mounted in a fragmentary portion of a boat hull.
Fig. 3 is a sectional View taken on the line 3 3 of Fig. 2, looking'in the direction indicated by the arrows.
In the construction shown in the draw: ings, elongated outer and inner casings 4 and 5, respectivel are integrally joined at their forward en s and are in' concentrically spaced relation abaft thereof, thus provid ing a passageway 6 therebetween.
' The inner casing 5 has an axially extending space or bore 7 therein, open at the front end, and in which is mounted an assembly of field coils 8. The rear end of the casing 5 terminates in spaced relation to the rear end of the outer casing 4, and is provided with an arma ture shaft bearing 9 and stuffing box 10.
` A cap 11 ofogival shape is detachably secured to the front of the casings by screws 12,
and serves as a closure for sealing the space 7,
a suitable gasket 30 being provided between the cap and the casing to seal the joint between them. The cap 11 carries anarmature shaft bearing or bushing 13 concentrically therein, in which is journaled the front end of an armature shaft 14, upon which is mounted an armature 15 within the field coils 8. The opposite end of the armature shaft 14 is journaled in the bearing 9, and rojects rearwardly through the stuffing box 0.
Such projecting end is provided with an impeller 16 secured thereon by a nut 17. rlhe impeller 16 is housed within the rear end of the outer casing 4 and a screen 18 is secured rearwardly thereof so as to protect the -impeller fromdama e.
The forward en of the outer casing 4, im-
mediately back of thenose cap 11, is provided with a plurality of water inlet ports 19, opening toward the side of the device rather than the front, which admit water to the annular passageway Q6 for acting on the impeller 16 .I
to rotate the same when the device is passed through the water.
Means are provided for attaching the device to the hull 20 of a boat and comprise a. radially extending shank 2l integrally formed with the outer casing. The outer end of the shank is exteriorly threaded to receivey a nut 22 which is screwed down on a gasket 23 interposed between the nut and the inner side of the hull through which the shank projects. This construction forms a simple and iicient means for securing the device to a oat.
Electric conductors 24 are provided in suitable passa eways which extend through the shank 21 or transmitting current collected by the brush 25 which rides on the commutator 26 of the generating unit. It will be noted that in this way the conductors 24 are protected against contact with the water or with foreign objects in the water.
Current generated by the unit may be carried by the conductors 24 to a storage battery 27, if desired, and thence to a running light 28 or other desired place. A conventional type of generator cut-out 29 may be inserted betweenthe generator and battery if desired.
same when said unit 1s passed through the 45 in spacedl relation thereto abaft of projectingshaft end for driving said uit.V` jecting beyond sadstuin ture on said shaft within 'said field coils, and l Y an outer casing,
/ water line.
p is commensurate with the appended within said outer` casing. c aims.
Aa casin a current said casing,
-way therebetween,
' Inethe operation of this device it is mounthoused within said inner casing and sealed ed on `the outer side of a boats hull below the against the entrance of water thereinto, a
As the boat moves forwardlyl drive shaft for said unit extending rearwardthrough the water a suction is created at the ly into the space provided by said outerv rear end of the casing, because of the shape casing, and animpeller on said shaft and of such end, and this suction causes a flow of -housed within said outer casing for driving water into the passageway 6y throu h the said generator. ports 19, and thence rearwardly out t rough 4. A `hydro-electric generator comprising the screen 18. Obviously, this flow of water an outer casing, an inner casing in concenagainst the impeller 16 will cause rotation trically spaced relation thereto providin thereof and a corresponding rotation of the a water passageway therebetween, one end o amature 15 with consequent power output said inner casing terminating in spaced relaby the generator. It may be desirable, in tion to the rear end of said outer casing, a some cases,toformareverse curve oroutward current generatinv'unit housed within said flare at the rear end ofthe casing as at 31, in 'inner casing, a drive shaft for said unit exorder to increase the suction at t e rear end tending into the space provided by said outer of the casin It will also be apparent that casing, and an impeller on said shaft and the relative ow of water against the ports 19 housed within said outer casing for driving will aid in causing the water to flow through said generator. the casing, and that scoops may be added to 5. A hydro-electric generator comprising aid the flow from this cause, but I prefer to an elongated tubular housing having water eliminate a material amount of flow by this intake ports adjacent the front end thereof method because of the greater possibility 'of and the rear end thereof permitting water clo 'ng the orts 19 by foreign matter. to be discharged therefrom, an inner casin though xI) show a conventional form of housed within said outer casin and termistuliing box 10 for sealin the rear end of the nati-iig in spaced relation to te rear end armatureshaft 14, it wi be obvious that any thereof, an electric enerator unit sealed suitable form of sealing device may be emagainst the entrance o water thereinto withplo ed at this point. in said inner casing, a drive shaft for said orm'al changes may be made in the speunit having one end projecting into the s ace ciic embodiment of the invention described at the rear end of said inner casing, an an without de arting from thespirit and subimp stance of the broad invention, the scope of driving said unit, said impeller being housed 6. A hydro-electric generator comprising an outer casing, an inner casing in spaced relation thereto providing a water passagegenerating unit within way therebetween, a current generating unit said casing, a drive shaft for said unit having housed within said inner casing, a drive shaft one end projecting through a stufling box in for said unit extending into the space proan impeller on said projecting' vided by said outer casing, and an impeller shaft end,'said casin havingawater passa 0n said shaft and housed within said outer wayleadingto Said impeller for rotatingt e casing for driving said generator, a shank )projecting from said outer casing for attachwater, a shank'on said casing for attaching. lng said device to a'boat hull, and electric said/device to a boat hull, and an electric conductors passin through said shank for through said shank for carrying current rom said current generat- I claim: J 1. A hydro-electric generator comprising conductor passing carryin current from said generating unit. ing llllit- 2.' A ydro-electric generator comprising 7. A h dro-electric generator comprising an outer casing adapted to be attached tov a, elongate inner and outer casin in con- 'boat hull, an inner casing integrally attached centrically spaced relation to provide a water at its forward end to said outer casi and SSBgeWay therebetween; Said inner casing s111151 ataving an axially extending space open at the tachment, said outer casin having water front end thereof, field coils mounted within inletl ports communicating with the tween said casings, a current generating unit.. Astaging box at the rear end of said inner sealed from the entrance of water thereinto Casing, a detachable cap for closing the front within said inner casing, a drive shaft for end of said space,.an armature shaft bearing said unit projecting through the rear end mounted in said cap, an armature shaft jourof said inner casing, andan impeller on said naled in said bearings with the rear end probox, an 'arma- 3. A- hydro-electric generator comprisin an inner casing in spa an'impeller on said projecting v shaft end for 'providing a water passagerotating said armature, sai
relation thereto outer casing ce besaid space,jan armature shaft bearing and` a current generating unit having a port therein for admitting water @ller on said projecting shaft end for l y to said passageway for driving said impeller.
` ing a shaft, vsaid shaft projecting rearwardly out of said compartment, andan impeller secured to said shaft between said compartment and the rear edge ofsaid casing, said casing having ports in the nose portion thereof rearwardly of the point of said nose for admittingwater into` the space between said compartment and the inner walls of said casing.
'9. In a generator` for boats, in combination, a hollow casing having a streamlined nose and an open rear end,'a water tight compartment within said casing spaced radiall i11- wardly from thel inner Walls the'eo an electric generator within said shaft project,
ing rearwardly out of said compartment, an impeller secured to said shaft between said compartment and the rear edge of said casling, said casing having ports in the nose portion thereof, for admitting water intol the space between Asaid compartment and the inner walls of said casing, and the outer walls of said casing adjacent the rear end thereof being outwardly curved to effect a, greater suction on said rear end during passage of said casing through water.
10. An electric power generating unit for boats, comprising a generally cylindrical ho1` low outer casing having a substantially pointed nose portion, a generating unit within said casing sealed. againstthe entrance of water and providing a water passage between it and said casing, said casing having water passages connecting said space with the exterior surface thereof at apoint removed from the extreme tip of said nose portion,- a drive shaft projectingfrom one end of said generating unit, and a propeller secured to said shaft within the protection of said casing and exposed to the How of water therethrough.
11. In an electric power generating unit for boats, a pair of generally spaced casing members one located within the other, the space between said members forming a water passage, a generating unit housed within the inner of said housings and sealed against the entrance of water thereinto, a lshaft for said unit projectingi' out of said inner casing, a propeller secured to said shaft externallyv of said inner casing but internally of the outer of said casings, and a nose portion for said 'Y outervcasing, said outer casing being open at the rear end thereof and having-intake openv` ings adjacent the. forward end thereof exposed l'primari y on the side faces of said outer ca' 12.A In an electric power generating unit for boats, a pair of generally spaced casing members one located within the other, the space between said members forming a water passage, a generating unit housed within the 'inner of said housings and sealed against the entrance of water thereinto, a shaft for said unit projecting out of'said inner casing, a
propeller secured to said shaft externally of said inner casing but internally of the outer of s ald casings, a nose portion for said outer casing, said outer casing being open at the rear end thereofand having intake openings ad] acent the forward end thereof exposed primarily on the side faces of said outer casing, and a screen mounted on said outer cas-r ing to protect said open rear end.
HERBERT D. ALLEE.
lum
US405227A 1929-11-06 1929-11-06 Generator for motor boats or the like Expired - Lifetime US1831835A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US405227A US1831835A (en) 1929-11-06 1929-11-06 Generator for motor boats or the like

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US405227A US1831835A (en) 1929-11-06 1929-11-06 Generator for motor boats or the like

Publications (1)

Publication Number Publication Date
US1831835A true US1831835A (en) 1931-11-17

Family

ID=23602820

Family Applications (1)

Application Number Title Priority Date Filing Date
US405227A Expired - Lifetime US1831835A (en) 1929-11-06 1929-11-06 Generator for motor boats or the like

Country Status (1)

Country Link
US (1) US1831835A (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2456834A (en) * 1945-01-31 1948-12-21 Napoli John Propulsion means for boats
US2533681A (en) * 1949-06-07 1950-12-12 Napoli John Propulsion means for boats
US3081251A (en) * 1958-10-31 1963-03-12 Spector Dov Self-powered cathodic protection and electrolytic descaling device
US3403654A (en) * 1965-12-30 1968-10-01 Wilson Wayne Watercraft propulsion
US3411013A (en) * 1966-04-04 1968-11-12 Roger G. Vogelsang Marine accessory drive
US3619632A (en) * 1969-06-02 1971-11-09 Raymond A Labombarde Outboard generator unit for sailboats
US3849982A (en) * 1972-04-03 1974-11-26 Hall Marine Corp Marine jet propulsion apparatus
US5644170A (en) * 1995-02-17 1997-07-01 Bynum; David A. Vechicle mounted atmospheric/aqua turbine having speed responsive intake means
US20100123316A1 (en) * 2008-11-18 2010-05-20 Fowler Benjamin P Power generator barge
US20110183554A1 (en) * 2008-07-14 2011-07-28 General Electric Company System and method for dynamic energy recovery in marine propulsion
DE102017100485A1 (en) * 2017-01-11 2018-07-12 Ocean Power GbR (vertretungsberechtigter Gesellschafter Eckard Scholz, 29351 Eldingen) Generator for generating electrical energy for a watercraft

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2456834A (en) * 1945-01-31 1948-12-21 Napoli John Propulsion means for boats
US2533681A (en) * 1949-06-07 1950-12-12 Napoli John Propulsion means for boats
US3081251A (en) * 1958-10-31 1963-03-12 Spector Dov Self-powered cathodic protection and electrolytic descaling device
US3403654A (en) * 1965-12-30 1968-10-01 Wilson Wayne Watercraft propulsion
US3411013A (en) * 1966-04-04 1968-11-12 Roger G. Vogelsang Marine accessory drive
US3619632A (en) * 1969-06-02 1971-11-09 Raymond A Labombarde Outboard generator unit for sailboats
US3849982A (en) * 1972-04-03 1974-11-26 Hall Marine Corp Marine jet propulsion apparatus
US5644170A (en) * 1995-02-17 1997-07-01 Bynum; David A. Vechicle mounted atmospheric/aqua turbine having speed responsive intake means
US20110183554A1 (en) * 2008-07-14 2011-07-28 General Electric Company System and method for dynamic energy recovery in marine propulsion
US8858277B2 (en) * 2008-07-14 2014-10-14 General Electric Company System and method for dynamic energy recovery in marine propulsion
US20100123316A1 (en) * 2008-11-18 2010-05-20 Fowler Benjamin P Power generator barge
DE102017100485A1 (en) * 2017-01-11 2018-07-12 Ocean Power GbR (vertretungsberechtigter Gesellschafter Eckard Scholz, 29351 Eldingen) Generator for generating electrical energy for a watercraft
DE102017100485B4 (en) * 2017-01-11 2021-06-10 Ocean Power GbR (vertretungsberechtigter Gesellschafter Eckard Scholz, 29351 Eldingen) Generator for generating electrical energy for a watercraft

Similar Documents

Publication Publication Date Title
US1831835A (en) Generator for motor boats or the like
US2714866A (en) Device for propelling a ship
ATE555006T1 (en) MARINE ENGINE UNIT
US5722864A (en) Marine propulsion system
US5967863A (en) Trolling motor
US1534451A (en) Combined rotary unit
SE0201341L (en) Outboard drive for boats
DE69906086D1 (en) ELECTRICALLY POWERED WATER VEHICLE
US1762957A (en) Outboard motor
EP0043162A1 (en) Improvements in electrically powered, submersible centrifugal pumps
GB1439806A (en) Electrically driven propeller
US1764388A (en) Electric motor and propeller unit
US2146623A (en) Inboard-outboard motorboat drive
US1724559A (en) Motor boat and propelling means therefor
DE3868929D1 (en) JET ENGINE FOR SHIPS.
US1991512A (en) Boat
US1112057A (en) Speed-boat.
US3361215A (en) Magnetic driving apparatus for electric fishing motors
NO831144L (en) Submersible pump with motor
GB2284943A (en) Liquid cooling coil in alternator casing
US1818991A (en) Water cooling system for marine motors
US1887540A (en) Sealing means for submersible motors
US1111988A (en) Propeller for boats.
GB283921A (en) Improvements in or relating to submersible electric motors
CN113300539B (en) Cooling and lubricating system of electric propeller