US2523651A - Propelling means - Google Patents

Propelling means Download PDF

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Publication number
US2523651A
US2523651A US658335A US65833546A US2523651A US 2523651 A US2523651 A US 2523651A US 658335 A US658335 A US 658335A US 65833546 A US65833546 A US 65833546A US 2523651 A US2523651 A US 2523651A
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Prior art keywords
sleeve
propeller
blade
blades
shaft
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Expired - Lifetime
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US658335A
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Doussain Robert
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C11/00Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
    • B64C11/02Hub construction
    • B64C11/04Blade mountings
    • B64C11/06Blade mountings for variable-pitch blades
    • 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
    • Y10S415/00Rotary kinetic fluid motors or pumps
    • Y10S415/912Interchangeable parts to vary pumping capacity or size of pump

Definitions

  • My invention relates to variable pitch propellers and has for its object a system providing for the standardization of its very design by ensuring a standardization of the different elements of these propellers.
  • My invention covers also a series of arrangements allowing this standardization and. this simplification to be reached.
  • variable pitch propeller is mounted in a manner such that a propeller including a predetermined number of blades may be replaced by a propeller having any other number of blades.
  • a further object of the invention is to provide standard socket units comprising a rotatable blade carrying member and a speed reducing mechanism for a proper pitch adjustment speed reduction, each socket unit being detachably anchored in the propeller hub structure for removal therefrom as a unit.
  • Fig. 1 is. an. end view of a shaft. carrying a fourblade propeller.
  • Fig. 2 is a view similar to Fig. l, partly in section, of a propeller with six blades mounted on a shaft.
  • Fig. 3 is a partly elevational, partly sectional end view on an enlarged scale of the propeller shown in Fig. 2.
  • Fig. 4 is a cross-sectional side view of the blade carrier block shown in Fig. 3 and of the shaft on which said blade carrier is mounted with the interposition of a sleeve, the viewbeing taken on the vertical center lineof Fig; 3.
  • V Fig. 5 is across-sectionalsideview constituting a continuation of Fig. 4 from the line Y--Y and particularly showing the transmission means controlling the variations in pitch.
  • Fig. 6 is an end view of one of the blade carrying blocks and shows a speed reducer of the Eade type incorporated in the blade carrying block.
  • the fluted shaft I is adapted to carry a propeller.
  • a sleeve 2 with inner fiutings forming part of the hub permanently fitted on the shaft.
  • This sleeve may be easily machined and its weight may be very small.
  • the sleeve 2 includes a vertical flange provided with a number of claws 55 preferably as large as possible,
  • the shaft i "maybe hollow in which case it receives at its end a ring ill for securing the sleeve 2 to the shaft I with two centering cones 56, 57?.
  • the sleeve 2 is adapted to receive the removable hub member proper 3.
  • a set of hub members each of which corresponds to a propeller comprising a certain number of blades. Whatever may be the number of blades, the execution of the central part of the hub member is the same, so that it may be secured With out any modification of the sleeve 2 on to the latter.
  • Figs. 1 and 2 there are shown respectively a four-blade hub and a six-blad hub secured to the same sleeve 2. It is apparent that this arrangement allows changing the propeller simply by unscrewing the nuts 4H and by fitting the desired hub member over the sleeve 2.
  • the hub member proper 3 includes according tov the number of its blades a corresponding number of seats 58 adapted to receive blade carrying socket units.
  • Each socket unit is constituted by a plurality of assembled parts.
  • One of these parts 3a is formed by a sleeve screwed into the seat formed by the removable hub member 3 through its lower edge, while the upper edge of part 30,. is provided with a head 59 inside which are mounted the bearings.
  • One of these bearings 60 including rollers is adapted to damp the action of centrifugal forces while the other bearing 6
  • the part of the socket unit receivin the blade is constituted by a rotatable member provided with 7 two cylindrical concentric parts connected by an annular wall perpendicular to the axis of the two cylinders.
  • the inner cylindrical part 4b of member 4 extends downwardly under the form of a sleeve 63 and the above-mentioned bearing 62 is inserted between the latter andthe lower end ofthe sleeve 3a.
  • the outer cylindrical portion of socket member 4, surrounding sleeve 3a is provided inside its lower outer edge with a screw thread inside which may be screwed a removable extension 4a provided with a bead 5
  • the upper part of the outer cylindrical portion of socket member 4 is also provided with an inner thread engaging the lower flange of the blade 5 which engages the gap between said threaded upper part of the outer cylindrical portion of socket member 4 and an annular projection 4 b providing for the centering of the blade in association with the upper edge 40 of the upper part of the outer cylindrical portion of socket member 4.
  • the change in pitch is provided by the engagement of the pinion I meshing automatically with the conical tooth-work 12 of a bevel wheel II, when the blade Carrying socket unit is being mounted.
  • the pinion I0 is fitted over the end of a shaft 6 mounted in the cylindrical inner space of the rotatable socket member 4 through the agency of roller bearings 64'. This pinion may control directly the rotation of the rotatable socket member 4 and consequently that of the blade 5.
  • speed reducing means associated with each blade-carrying socket unit.
  • Said reducing means may be of the Eade type as illustrated by way of example in the drawings.
  • Fig. 6 designates a gear eccentrically carried by the shaft 6; 1 designates the inner tooth-work of the sleeve 63 and 9 and 9a the centering device for the gear 8.
  • Fig. 6 is shown in plan view the manner of executing said speed reducing means. It includes a guiding cross piece 52 adapted to slide from the left hand side to the right hand side of Fig. 6.
  • the gear 8 includes two guiding members 68 adapted to engage slideways 54 cut inside the body of the cross piece 52.
  • the gear 8 is capable of receiving only a circular translational movement.
  • the drive of the bevel wheel II is produced by means of a stationary control device such for instance as a jack of the hydraulic, electric or mechanical type. 7 It is to be understood that the above described embodiment of my invention is for the purpose of illustration only, and various changes may be made therein without departing from the spirit or scope of the invention.
  • a variable pitch propeller comprising in combination with a propeller shaft and a selected number of propeller blades, a bevel wheel disposed around said propeller shaft, control means -.-0
  • a hub structure having a removable hub portion forming a number of seatings corresponding to the number of blades, a number of standard socket units corresponding to the number of blades, each socket unit having a sleeve member detachably fastened in said seating and a blade carrying member rotatably mounted within said sleeve member and carrying one of said blades, a bevel gear mounted within each rotatable member in order to be driven by said 4 bevel wheel, and a speed reducing gearing interposed ioetween each bevel gear and each rotatable member.
  • a variable pitch propeller comprising in combination with a propeller shaft and a selected number of propeller blades, a bevel wheel disposed around said propeller shaft, control means for the pitch adjustment acting on said bevel wheel, a hub structure having a removable hub member forming a number of seatings corresponding to the selected number of blades, a number of standard socket units corresponding to the selected number of blades, each socket unit having a sleeve member detachably fastened in one of said seatings and a blade carrying member ,rotatably mounted within said sleeve member and carrying one of said blades, said rotatable member having a cylindrical central portion extending within said sleeve member and an annular outer portion surrounding said sleeve member, atleast one bearing between said annular portion and said sleeve member adapted to take the thrust due to centrifugal force, at least one bearing between said central portion and said sleeve member adapted to take the lateral thrust of the blade, a bevel gear mounted on

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Description

Sept. 26, 1950 R. DOUSSAIN 2,523,651
PROPELLING MEANS Filed March 29, 1946 6 Sheets-Sheet 1 Fig.1
p 26,1950 I R. Db'usisAm 2,523,651
' PROPELLING MEANS Filed March 29, 1946 I s Sheets-Sheet s R. DOUSSAIN PROPELLING MEANS Sept. 26, 1950 Filed March 29, 1946 5 e Sheets-Sheet 4 Fig.4
a up
Sept. 26, 1950 R. n ou' ssAm PROPELLING MEANS I 6 I Sheets-Sheet 5 Filed March 29, 1946 Sept. 26,1950 R. ooussAm 2,523,651
' PROPELLING MEANS I Filed March 29, 1946 6 Sheets-Sheet 6 Patented Sept. 26, 1950 OFFICE PROPELLIN G MEANS Robert Doussain, Villeurbanne, France.
Application March 29, 1946, Serial No. 658,335 In France September 26, 1945 2 Claims. (Cl. 17'0--160.48)
My invention relates to variable pitch propellers and has for its object a system providing for the standardization of its very design by ensuring a standardization of the different elements of these propellers.
My invention covers also a series of arrangements allowing this standardization and. this simplification to be reached.
According to my invention, the variable pitch propeller is mounted in a manner such that a propeller including a predetermined number of blades may be replaced by a propeller having any other number of blades. A further object of the invention is to provide standard socket units comprising a rotatable blade carrying member and a speed reducing mechanism for a proper pitch adjustment speed reduction, each socket unit being detachably anchored in the propeller hub structure for removal therefrom as a unit.
My invention will be better understood by referring to the following description and accompanying drawing showing by way of example a form of execution of my invention.
Said description will make further features .In said drawings:
Fig. 1 is. an. end view of a shaft. carrying a fourblade propeller.
Fig. 2 is a view similar to Fig. l, partly in section, of a propeller with six blades mounted on a shaft.
Fig. 3 is a partly elevational, partly sectional end view on an enlarged scale of the propeller shown in Fig. 2.
Fig. 4 is a cross-sectional side view of the blade carrier block shown in Fig. 3 and of the shaft on which said blade carrier is mounted with the interposition of a sleeve, the viewbeing taken on the vertical center lineof Fig; 3.
V Fig. 5 is across-sectionalsideview constituting a continuation of Fig. 4 from the line Y--Y and particularly showing the transmission means controlling the variations in pitch.
Fig. 6 is an end view of one of the blade carrying blocks and shows a speed reducer of the Eade type incorporated in the blade carrying block.
Reverting to the drawings, the fluted shaft I is adapted to carry a propeller. To this shaft is rigidly secured a sleeve 2 with inner fiutings forming part of the hub permanently fitted on the shaft. This sleeve may be easily machined and its weight may be very small. The sleeve 2 includes a vertical flange provided with a number of claws 55 preferably as large as possible,
and. advantages of my invention appear clear- At M are'shown the securing nuts. The shaft i "maybe hollow in which case it receives at its end a ring ill for securing the sleeve 2 to the shaft I with two centering cones 56, 57?. The sleeve 2 is adapted to receive the removable hub member proper 3.
According to my invention, there is provided a set of hub members each of which corresponds to a propeller comprising a certain number of blades. Whatever may be the number of blades, the execution of the central part of the hub member is the same, so that it may be secured With out any modification of the sleeve 2 on to the latter. In Figs. 1 and 2 there are shown respectively a four-blade hub and a six-blad hub secured to the same sleeve 2. It is apparent that this arrangement allows changing the propeller simply by unscrewing the nuts 4H and by fitting the desired hub member over the sleeve 2.
The hub member proper 3 includes according tov the number of its blades a corresponding number of seats 58 adapted to receive blade carrying socket units. Each socket unit is constituted by a plurality of assembled parts. One of these parts 3a is formed by a sleeve screwed into the seat formed by the removable hub member 3 through its lower edge, while the upper edge of part 30,. is provided with a head 59 inside which are mounted the bearings. One of these bearings 60 including rollers is adapted to damp the action of centrifugal forces while the other bearing 6| including balls is adapted, in association with a third bearingincluding rollers 62 located towards the bottom of the seat, to provide the blade with the required freedom of rotation. The part of the socket unit receivin the blade is constituted by a rotatable member provided with 7 two cylindrical concentric parts connected by an annular wall perpendicular to the axis of the two cylinders. The inner cylindrical part 4b of member 4 extends downwardly under the form of a sleeve 63 and the above-mentioned bearing 62 is inserted between the latter andthe lower end ofthe sleeve 3a. The outer cylindrical portion of socket member 4, surrounding sleeve 3a is provided inside its lower outer edge with a screw thread inside which may be screwed a removable extension 4a provided with a bead 5| carrying the second race of the bearing 60. The upper part of the outer cylindrical portion of socket member 4 is also provided with an inner thread engaging the lower flange of the blade 5 which engages the gap between said threaded upper part of the outer cylindrical portion of socket member 4 and an annular projection 4 b providing for the centering of the blade in association with the upper edge 40 of the upper part of the outer cylindrical portion of socket member 4. With this manner of mounting the elements, it is apparent that the anchoring of the blade is separate from the bearing adapted to damp the effect of centrifugal force and from those which ensure the degree of rotary freedom required for the change in pitch.
The change in pitch is provided by the engagement of the pinion I meshing automatically with the conical tooth-work 12 of a bevel wheel II, when the blade Carrying socket unit is being mounted. The pinion I0 is fitted over the end of a shaft 6 mounted in the cylindrical inner space of the rotatable socket member 4 through the agency of roller bearings 64'. This pinion may control directly the rotation of the rotatable socket member 4 and consequently that of the blade 5. However, as explained at the beginning of the specification, there are provided according to my invention speed reducing means associated with each blade-carrying socket unit. Said reducing means may be of the Eade type as illustrated by way of example in the drawings. 8 designates a gear eccentrically carried by the shaft 6; 1 designates the inner tooth-work of the sleeve 63 and 9 and 9a the centering device for the gear 8. In Fig. 6 is shown in plan view the manner of executing said speed reducing means. It includes a guiding cross piece 52 adapted to slide from the left hand side to the right hand side of Fig. 6. The gear 8 includes two guiding members 68 adapted to engage slideways 54 cut inside the body of the cross piece 52. Thus the gear 8 is capable of receiving only a circular translational movement.
The drive of the bevel wheel II is produced by means of a stationary control device such for instance as a jack of the hydraulic, electric or mechanical type. 7 It is to be understood that the above described embodiment of my invention is for the purpose of illustration only, and various changes may be made therein without departing from the spirit or scope of the invention.
What I claim is:
v 1. A variable pitch propeller comprising in combination with a propeller shaft and a selected number of propeller blades, a bevel wheel disposed around said propeller shaft, control means -.-0
for the pitch adjustment acting on said bevel wheel, a hub structure having a removable hub portion forming a number of seatings corresponding to the number of blades, a number of standard socket units corresponding to the number of blades, each socket unit having a sleeve member detachably fastened in said seating and a blade carrying member rotatably mounted within said sleeve member and carrying one of said blades, a bevel gear mounted within each rotatable member in order to be driven by said 4 bevel wheel, and a speed reducing gearing interposed ioetween each bevel gear and each rotatable member.
2. A variable pitch propeller comprising in combination with a propeller shaft and a selected number of propeller blades, a bevel wheel disposed around said propeller shaft, control means for the pitch adjustment acting on said bevel wheel, a hub structure having a removable hub member forming a number of seatings corresponding to the selected number of blades, a number of standard socket units corresponding to the selected number of blades, each socket unit having a sleeve member detachably fastened in one of said seatings and a blade carrying member ,rotatably mounted within said sleeve member and carrying one of said blades, said rotatable member having a cylindrical central portion extending within said sleeve member and an annular outer portion surrounding said sleeve member, atleast one bearing between said annular portion and said sleeve member adapted to take the thrust due to centrifugal force, at least one bearing between said central portion and said sleeve member adapted to take the lateral thrust of the blade, a bevel gear mounted on a shaft disposed within said central portion of the rotatable member of each socket unit, and a speed reducing mechanism interposed between said bevel gear and said central portion of the rotatable socket member.
ROBERT DOUSSAIN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name 1 Date 1,951,320 Blanchard Mar. 13, 1934 1,969,280 Smith Aug. 7, 1934 2,108,660 Farrell Feb. 15, 1938 2,147,078 Barish Feb. 14, 1939 2,182,285 DeCaria Dec. 5, 1939 2,232,683 Lloyd Feb. 25, 1941 2,338,420 Freitag Jan. 4, 1944 2,367,230 McCoy Jan. 16, 1945 2,392,556 Seppeler Jan. 8, 1946 FOREIGN PATENTS Number Country Date 50,162 France (Addition to 844,832)
240,291 Great Britain Oct. 1, 1925 384,424 Great Britain Dec. 8, 1932 483,760 Great Britain Apr. 26, 1938 505,169 Great Britain May 4, 1939 518,217 France Dec. 27, 1920 550,354 Great Britain Jan. 5, 1943 768,696 France May 28, 1934 787,622 France Sept. 26, 1935
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3227399A (en) * 1963-09-16 1966-01-04 Dastoli Joseph Safety aircraft system
EP2730502A1 (en) * 2012-11-09 2014-05-14 Hamilton Sundstrand Corporation Hub piloting diameter with relief cuts

Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR518217A (en) * 1920-06-28 1921-05-21 Pierre Jacomy Propulsion propeller with variable pitch and diameter
GB240291A (en) * 1924-09-19 1925-10-01 Napier & Son Ltd Improvements in or relating to propellers for aircraft
GB384424A (en) * 1931-11-24 1932-12-08 Roe A V & Co Ltd Improvements relating to variable pitch propellers
US1951320A (en) * 1930-09-16 1934-03-13 Curtiss Aeroplane & Motor Co Variable pitch propeller
US1969280A (en) * 1932-06-30 1934-08-07 Bendix Aviat Corp Propeller
FR768696A (en) * 1934-02-01 1934-08-10 Variable pitch propeller and devices which can be used separately therein
FR787622A (en) * 1934-06-21 1935-09-26 Pour L Aviat Soc Et Variable pitch propeller in flight
US2108660A (en) * 1938-02-15 Variable pitch and reversing pro
GB483760A (en) * 1936-12-16 1938-04-26 Fairey Aviat Co Ltd Improvements in or relating to variable pitch propellers, especially for aircraft
US2147078A (en) * 1935-08-05 1939-02-14 Aviat Mfg Corp Controllable pitch propeller
GB505169A (en) * 1936-08-04 1939-05-04 United Aircraft Corp Improvements in or relating to screw propellors
FR844832A (en) * 1938-04-15 1939-08-02 Pour L Aviat Soc Et Device for controlling the variation of the pitch of a variable-pitch propeller in flight.
US2182285A (en) * 1937-06-05 1939-12-05 Caria Ugo De Adjusting mechanism for propeller blades and the like
FR50162E (en) * 1938-09-07 1940-01-17 Pour L Aviat Soc Et Device for controlling the variation of the pitch of a variable-pitch propeller in flight
US2232683A (en) * 1940-04-25 1941-02-25 Charles W Lloyd Pitch changing mechanism for oppositely rotating propellers for aircraft
GB550354A (en) * 1941-05-23 1943-01-05 Oscar Charles Jackson Variable pitch co-axial airscrews
US2338420A (en) * 1938-10-13 1944-01-04 Freitag Reinhold Arrangement for adjusting the blades of opposite rotating air propellers
US2367230A (en) * 1943-12-09 1945-01-16 Howard M Mccoy Controllable pitch-change mechanism for dual rotation propellers
US2392556A (en) * 1939-02-16 1946-01-08 Seppeler Eduard Adjusting pitch of screws

Patent Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2108660A (en) * 1938-02-15 Variable pitch and reversing pro
FR518217A (en) * 1920-06-28 1921-05-21 Pierre Jacomy Propulsion propeller with variable pitch and diameter
GB240291A (en) * 1924-09-19 1925-10-01 Napier & Son Ltd Improvements in or relating to propellers for aircraft
US1951320A (en) * 1930-09-16 1934-03-13 Curtiss Aeroplane & Motor Co Variable pitch propeller
GB384424A (en) * 1931-11-24 1932-12-08 Roe A V & Co Ltd Improvements relating to variable pitch propellers
US1969280A (en) * 1932-06-30 1934-08-07 Bendix Aviat Corp Propeller
FR768696A (en) * 1934-02-01 1934-08-10 Variable pitch propeller and devices which can be used separately therein
FR787622A (en) * 1934-06-21 1935-09-26 Pour L Aviat Soc Et Variable pitch propeller in flight
US2147078A (en) * 1935-08-05 1939-02-14 Aviat Mfg Corp Controllable pitch propeller
GB505169A (en) * 1936-08-04 1939-05-04 United Aircraft Corp Improvements in or relating to screw propellors
GB483760A (en) * 1936-12-16 1938-04-26 Fairey Aviat Co Ltd Improvements in or relating to variable pitch propellers, especially for aircraft
US2182285A (en) * 1937-06-05 1939-12-05 Caria Ugo De Adjusting mechanism for propeller blades and the like
FR844832A (en) * 1938-04-15 1939-08-02 Pour L Aviat Soc Et Device for controlling the variation of the pitch of a variable-pitch propeller in flight.
FR50162E (en) * 1938-09-07 1940-01-17 Pour L Aviat Soc Et Device for controlling the variation of the pitch of a variable-pitch propeller in flight
US2338420A (en) * 1938-10-13 1944-01-04 Freitag Reinhold Arrangement for adjusting the blades of opposite rotating air propellers
US2392556A (en) * 1939-02-16 1946-01-08 Seppeler Eduard Adjusting pitch of screws
US2232683A (en) * 1940-04-25 1941-02-25 Charles W Lloyd Pitch changing mechanism for oppositely rotating propellers for aircraft
GB550354A (en) * 1941-05-23 1943-01-05 Oscar Charles Jackson Variable pitch co-axial airscrews
US2367230A (en) * 1943-12-09 1945-01-16 Howard M Mccoy Controllable pitch-change mechanism for dual rotation propellers

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3227399A (en) * 1963-09-16 1966-01-04 Dastoli Joseph Safety aircraft system
EP2730502A1 (en) * 2012-11-09 2014-05-14 Hamilton Sundstrand Corporation Hub piloting diameter with relief cuts
US9399921B2 (en) 2012-11-09 2016-07-26 Hamilton Sundstrand Corporation Hub piloting diameter with relief cuts

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