US1806325A - Adjustable and reversible propeller for aeroplanes or other aircraft - Google Patents

Adjustable and reversible propeller for aeroplanes or other aircraft Download PDF

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US1806325A
US1806325A US435070A US43507030A US1806325A US 1806325 A US1806325 A US 1806325A US 435070 A US435070 A US 435070A US 43507030 A US43507030 A US 43507030A US 1806325 A US1806325 A US 1806325A
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blades
propeller
aeroplanes
aircraft
adjustable
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US435070A
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Roy F Wooden
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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
    • B64C11/30Blade pitch-changing mechanisms
    • B64C11/32Blade pitch-changing mechanisms mechanical
    • B64C11/36Blade pitch-changing mechanisms mechanical non-automatic

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  • This invention relates to adjustable and reversible propellers for aeroplanes or other aircraft.
  • the main object of the invention is to provide a means whereby the blades of a propeller may be axially shifted without lnterfering with their rotation so as to increase their pitch when taking off or flying m high altitudes or decrease their pitch when land- 10 ing or warming the engine and reverse their pitch to serve as a brake when landing.
  • ' 'Another object is to provide a novel and very efficient mounting for the propeller blades in which they are connected and jour- '15 naled together at relatively widely separated points in such manner that they may freely rotate on their axis for adjustment of pitc but cannot. move out of their proper longitudinal alignment under the strains brought '20 about by the rapid rotation of the propeller in flight.
  • a further object is to provide a simple and efficient remotely controlled means for shifting the blades to vary their pitch.
  • Figure 1 is a side elevation ofthe propeller and theblade adjusting mechanism as installed on an aeroplane, the latter being shown a '86" in dotted lines.
  • Figure 2 is an enlarged section along the line 2-2 in Figure 1.
  • I Figure 3 is an enlarged section along the line 33 in Figure 2.
  • Figure 4 is an enlarged section along the line 4-4 in Figure 2.
  • Figure 5 is a view similar to Figure 4 but illustrating the blades in a different position or set at a different-pitch.
  • Figure 6 is an enlarged section along the line 66 in Figure 1.
  • Figure 7 is an elevation of the blade shifting lever.
  • Figure 8 is a plan view of a portion of the blade shifting mechanism and lever.
  • Figure 9 is an enlarged front elevation of the wedging plate for securing the pro eller hub to the propeller shaft, the latter eing also shown in end elevation in this view.
  • Figure 10 is an enlarged cross section an annulus 5 is extended from this end plate outwardly of the hub, threads being provided inside this annulus 5 as shown at 6.
  • the end of the engine drive shaft or propeller shaft 7 is externally threaded as shown at 8 for the reception of this annulus 5 thereb providing a connection between the hub 1 and the engine, a portion of which is shown in Figure 1 in the dotted lines 9.
  • the engine 9 may be of any suitable and conventional form'and is mounted within the nose 10 of the aeroplane (also shown in dotted lines) in the usual manner. Segments of the threads 8 on the shaft 7 are cut away longitudinally of the shaft as shown at 11 and complementary segments are cut from the threads 6 in theannulus 5 as shown at 12.
  • a circular fastening plate 13 is provided, the same having a central opening 14 around the margin of which are provided spaced keys or wedges 15 extended outwardly at right angles from the face of the plate. Slots 16 are provided through the plate 13 for the passage of bolts 17 by means of which the plate may be secured to t e inside of the end plate 3.
  • the annulus 5 is threaded thereon a substantial distance and the cut away segments 11 and 12 of the threads 6 and 8 are brought into alignment or registry.
  • the wedges 15 are then inserted into the slots thus provided as shown in Figure 6 of the drawing and the bolts 17 are tightened driving the said wedges home and forming a rigid connection between the hub and shaft.
  • a stop -ring 18 is secured on the shaft 7 and spacing washer 19 may be placed between this rin and the end of the annulus 5 to facilitate t e rigid connection of these elements theannulus 5 being screwed down ainst these washers as shown.
  • the annulus 5 is journaled in a ball bearing 20 provided in the crank case 21 of the engine 9 and a packing'washer 22 is secured over this hearing by the gland 23 to prevent the escape of oil from the crankcase but this assembly will of course vary according to the type of engine used.
  • the propeller blades 24 and 25 are conventional in form except for their inner end portions 26 which are rounded and journaled through apertures 27 provided in the ends 28 of the receptacle 2 for this purpose.
  • Ball thrust bearings 29 are provided within the receptacle 2 and these inner ends 26 of the propeller blades are secured to the inner races 30 of these bearings 29 and held against longitudinal displacement therein by looking rings 31 seated in the blades and bearing races 30 as shown.
  • the propeller blades 24 and 25 are angularly cut away at 32 and channeled or grooved at 33 withln the bearings 29 and adjacent thereto and are then tapered and rounded as shown at 44 and extended angularly inward toward their axis to terminate in axially extended journals 34.
  • the blades are also provided with bores 35 extended axially outward from the channels 33 for the reception of the journals 34.
  • the journal 34 of each blade is inserted in the bore .35 of the other blade thus connecting the blades together and at the same time allowing them to rotate independentl upon their axis.
  • the channel 33 of each b ade receives the inwardly extending portion 44 of the other blade and allows the same to rotate as will be understood.
  • Ball bearings 36 are seated in enlarged mouths 37 rovided at the inner ends of the bores 35 an the said journals 34 are mounted through these hearings.
  • Expansion coil springs 38 are braced between fixed collars 39 on the jgurnals" 34 and the bearings 36 to hold the latter in place.
  • the bores 35 are considerably longer than the journals 34 and thrust bearing carriers 40 are slidably mounted in these bores and normally urged inward into engagement with the ends of the journals by the expansion coil springs 41 which are braced between the said carriers and the end of the said bores.
  • the car- .riers 40 carry ball bearings 42 which seat in sockets 43 provided for s purpose in the ends of the journals 34.
  • Forks orlinks 52 are threaded on the free ends of the rods 50 and locked by lock nuts 53 and a square or angular-enlarged shoulder 54 is provided on these rods 50 intermediate their ends so that the distance between the forks 52 and the arm 47 may be varied as will be understood.
  • End forks or links 55 are pivotally mounted at 56 in the .clefts in the forks 52 as shown. Attaching studs or ears 57 are secured to the outer faces of the inner ends 26 of the propeller blades 24 and 25 at points substantially at the junction of the channeled sections 33 and the tapered rounded portions 44 of these blades as shown.
  • a ball bearing- 62 is loosely mounted on the shaft 7 and its-inner race 63 carries an annulus 64 which is provided with apertures 65 for the reception of the ends of the pin 60, the said bearing and slide rod 46 being thus connected together.
  • "An operating arm 66 is fulcrumed at 67 to any suitable part of the aeroplane or engine (not shown) and has one end bifurcated at 68 and adapted to embrace the outer race 69 of the ball bearing'62 to which race the forks 7.0 of this arm are pivoted by means of the bolts 71.
  • a hand lever 72 is provided and the same is pivoted at 73 to any suitable part of the plane within the cock pit and handy to the pilots hand.
  • a link 74 is pivotally attached at its ends as shown at 75 to the freeend of the arm 661and to the hand lever so that a swinging movement of the latter will bring about a shifting of the bearing 62 and slide rod 46 to vary the pitch of the propeller blades 24 and 25 as will be understood.
  • a rod 76- is slidably mounted lengthwise in the'hand lever 7 2 and carries at its lower enda pawl 77 adapted to engage Ill the serrated face of a quadrant 78 which is position. The rod 76 is operated to engage or disengage the pawl 77 by a finger button 79, and the said pawl is normally held in engagement with the quadrant 78 by means of acoil spring 80 arranged as shown.
  • the front wall thereof is rovided with an aperture 81 normally closed y a plate 82 secured in place by screws 83.
  • This plate 82 carries on its inner face a threaded bar 84 upon which is threadedly mounted the counter weight 85 and lock nuts 86 so that the propeller may be balanced as will be understood. After the propeller is balanced the counterweight 85 is 'secured'in its adjusted position by the lock nuts 86.
  • a pair of propeller blades with rounded inner end portions journaled in the said shell, the said rounded inner end portions havi channels in one side and having bores opening out into the said channels, journals on the same ends of the said pro peller blades, the journal of each blade being journaled in the bore of the other blade, and means for rotating the blades on their longitudinal axis.
  • ail elongated receptacle transversely mounted of the bl on the hub, a pair of ropelle'r blades, the
  • a device of the kind described in combination with the drive shaft of an engine, the said drive shaft having a longitudinal bore openin out through its end and havin diametrica y opposite slots through journal respectively of its wa near the inner end of the said bore ing the said connecting rods to the studs onthe propeller blades, a bearing slidably mounted on the said drive shaft over the slots therein, the inner race of the said bearing being connected to the inner end of the slide rod through the said slots, and manually operable means for shifting the said bearing lon 'tudinall ter ering with its rotation.
  • a pair of mated propellers including the shanks and blades, the inner end of each shank bein cut away 'and formed with an axially alifie journal at its-extremity and a bearing re spaced from; the said journal, the intermediate portion of each shank being channeled and cut out longitudinally and an larly so as to permit the two said oppose journals of the radially assembled pro llers, to enter the two said opposed bores, w ereby the twopropellers may oscillate inde ndently upon their axis to varytheir pitc and yet will mutually support one another against torque.

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

Description

y 1931- R. F. WOODEN ,8 5
ADJUSTABLE AND REVERSiBLE BROPELLER FOR AEROPLANES 'OR OTHER AIRCRAFT Filed March 12, 1930 3 Sheets-Sheet 1 R. F. WOODEN ADJUSTABLE AND REVERSIBLE PROPELLER FOR AEROPLANES OR OTHER AIRCRAFT May 19, 1931.
* 3 Sheets-Sheet Filed March 12, 1930 May 19, 1931. R. F. WOODEN 1,305,325
ADJUSTABLE AND REVERSIBLE PROPELLER FOR AEROPLANES OR OTHER AIRCRAFT Filed March 12, 1930 3 Sheets-Sheet 3 duotmq Patented May 19, 1931 UNITED STATES PATENT OFFICE ROY I. WOODEN, F MOUNT VERNON, ILLINOIS Application filed March 12, 1930. Serial No. 435,070.
This invention relates to adjustable and reversible propellers for aeroplanes or other aircraft.
The main object of the invention is to provide a means whereby the blades of a propeller may be axially shifted without lnterfering with their rotation so as to increase their pitch when taking off or flying m high altitudes or decrease their pitch when land- 10 ing or warming the engine and reverse their pitch to serve as a brake when landing.
' 'Another object is to provide a novel and very efficient mounting for the propeller blades in which they are connected and jour- '15 naled together at relatively widely separated points in such manner that they may freely rotate on their axis for adjustment of pitc but cannot. move out of their proper longitudinal alignment under the strains brought '20 about by the rapid rotation of the propeller in flight.
A further object is to provide a simple and efficient remotely controlled means for shifting the blades to vary their pitch.
The foregoing and other objects of the invention together with means whereby the same may be carried into effect will best be understood from the following description of a preferred embodiment of the invention '80 taken in connection with the accompanying drawings wherein: Figure 1 is a side elevation ofthe propeller and theblade adjusting mechanism as installed on an aeroplane, the latter being shown a '86" in dotted lines.
Figure 2 "is an enlarged section along the line 2-2 in Figure 1. I Figure 3 is an enlarged section along the line 33 in Figure 2. e a
Figure 4 is an enlarged section along the line 4-4 in Figure 2.
Figure 5 is a view similar to Figure 4 but illustrating the blades in a different position or set at a different-pitch.
Figure 6 is an enlarged section along the line 66 in Figure 1.
Figure 7 is an elevation of the blade shifting lever.
' Figure 8 is a plan view of a portion of the blade shifting mechanism and lever.
Figure 9 is an enlarged front elevation of the wedging plate for securing the pro eller hub to the propeller shaft, the latter eing also shown in end elevation in this view.
Figure 10 is an enlarged cross section an annulus 5 is extended from this end plate outwardly of the hub, threads being provided inside this annulus 5 as shown at 6. The end of the engine drive shaft or propeller shaft 7 is externally threaded as shown at 8 for the reception of this annulus 5 thereb providing a connection between the hub 1 and the engine, a portion of which is shown in Figure 1 in the dotted lines 9. The engine 9 may be of any suitable and conventional form'and is mounted within the nose 10 of the aeroplane (also shown in dotted lines) in the usual manner. Segments of the threads 8 on the shaft 7 are cut away longitudinally of the shaft as shown at 11 and complementary segments are cut from the threads 6 in theannulus 5 as shown at 12. A circular fastening plate 13 is provided, the same having a central opening 14 around the margin of which are provided spaced keys or wedges 15 extended outwardly at right angles from the face of the plate. Slots 16 are provided through the plate 13 for the passage of bolts 17 by means of which the plate may be secured to t e inside of the end plate 3. In mounting the hub 1 on the engine shaft 7 the annulus 5 is threaded thereon a substantial distance and the cut away segments 11 and 12 of the threads 6 and 8 are brought into alignment or registry. The wedges 15 are then inserted into the slots thus provided as shown in Figure 6 of the drawing and the bolts 17 are tightened driving the said wedges home and forming a rigid connection between the hub and shaft. A stop -ring 18 is secured on the shaft 7 and spacing washer 19 may be placed between this rin and the end of the annulus 5 to facilitate t e rigid connection of these elements theannulus 5 being screwed down ainst these washers as shown. As shown in Fi re 6 the annulus 5 is journaled in a ball bearing 20 provided in the crank case 21 of the engine 9 and a packing'washer 22 is secured over this hearing by the gland 23 to prevent the escape of oil from the crankcase but this assembly will of course vary according to the type of engine used.
The propeller blades 24 and 25 are conventional in form except for their inner end portions 26 which are rounded and journaled through apertures 27 provided in the ends 28 of the receptacle 2 for this purpose. Ball thrust bearings 29 are provided within the receptacle 2 and these inner ends 26 of the propeller blades are secured to the inner races 30 of these bearings 29 and held against longitudinal displacement therein by looking rings 31 seated in the blades and bearing races 30 as shown. The propeller blades 24 and 25 are angularly cut away at 32 and channeled or grooved at 33 withln the bearings 29 and adjacent thereto and are then tapered and rounded as shown at 44 and extended angularly inward toward their axis to terminate in axially extended journals 34. The blades are also provided with bores 35 extended axially outward from the channels 33 for the reception of the journals 34. The journal 34 of each blade is inserted in the bore .35 of the other blade thus connecting the blades together and at the same time allowing them to rotate independentl upon their axis. The channel 33 of each b ade receives the inwardly extending portion 44 of the other blade and allows the same to rotate as will be understood. Ball bearings 36 --are seated in enlarged mouths 37 rovided at the inner ends of the bores 35 an the said journals 34 are mounted through these hearings.
Expansion coil springs 38 are braced between fixed collars 39 on the jgurnals" 34 and the bearings 36 to hold the latter in place. The bores 35 are considerably longer than the journals 34 and thrust bearing carriers 40 are slidably mounted in these bores and normally urged inward into engagement with the ends of the journals by the expansion coil springs 41 which are braced between the said carriers and the end of the said bores. The car- .riers 40 carry ball bearings 42 which seat in sockets 43 provided for s purpose in the ends of the journals 34. By the foregoing construction it will be readily apparent that the propeller blades 24 and 25 are securely mounted within the receptacle 2 and cannot vibrate or chatter due to their rapid rota-. tion in use, Iyet,fat the same time the blades may be free y and independently rotated on their axis to change their pitch.
rod being threaded in theaforesaid apertures 49 in the arm 47 and locked by a lock nut 51. Forks orlinks 52 are threaded on the free ends of the rods 50 and locked by lock nuts 53 and a square or angular-enlarged shoulder 54 is provided on these rods 50 intermediate their ends so that the distance between the forks 52 and the arm 47 may be varied as will be understood. End forks or links 55 are pivotally mounted at 56 in the .clefts in the forks 52 as shown. Attaching studs or ears 57 are secured to the outer faces of the inner ends 26 of the propeller blades 24 and 25 at points substantially at the junction of the channeled sections 33 and the tapered rounded portions 44 of these blades as shown. The end forks 55 are pivotally connected to these studs 57 .by the bolts 58, the said studs entering into the clefts of the forks for this purpose as shown. It will now be understood that a longitudinal or axial shifting of the slide rod 46 in the bore 45 will cause the propeller blades 24 and 25 to be shifted to vary their pitch. For this purpose diametrically opposite and longitudinally extended slots 59 are provided in the engine shaft 7 adjacent the inner end of the bore 45 and in communication therewith thus providing a slideway for a pin 60 which is 'threaded diametrically through the slide rod 46' near its end as shown at 61. A ball bearing- 62 is loosely mounted on the shaft 7 and its-inner race 63 carries an annulus 64 which is provided with apertures 65 for the reception of the ends of the pin 60, the said bearing and slide rod 46 being thus connected together. "An operating arm 66 is fulcrumed at 67 to any suitable part of the aeroplane or engine (not shown) and has one end bifurcated at 68 and adapted to embrace the outer race 69 of the ball bearing'62 to which race the forks 7.0 of this arm are pivoted by means of the bolts 71. A hand lever 72 is provided and the same is pivoted at 73 to any suitable part of the plane within the cock pit and handy to the pilots hand. A link 74 is pivotally attached at its ends as shown at 75 to the freeend of the arm 661and to the hand lever so that a swinging movement of the latter will bring about a shifting of the bearing 62 and slide rod 46 to vary the pitch of the propeller blades 24 and 25 as will be understood. A rod 76-is slidably mounted lengthwise in the'hand lever 7 2 and carries at its lower enda pawl 77 adapted to engage Ill the serrated face of a quadrant 78 which is position. The rod 76 is operated to engage or disengage the pawl 77 by a finger button 79, and the said pawl is normally held in engagement with the quadrant 78 by means of acoil spring 80 arranged as shown.
In order to allow access to the mechanism in the receptacle 2 the front wall thereof is rovided with an aperture 81 normally closed y a plate 82 secured in place by screws 83. This plate 82 carries on its inner face a threaded bar 84 upon which is threadedly mounted the counter weight 85 and lock nuts 86 so that the propeller may be balanced as will be understood. After the propeller is balanced the counterweight 85 is 'secured'in its adjusted position by the lock nuts 86.
While I have herein set forth a certain preferred embodiment of my invention it is understood that I may vary from the same in minor details so as best to construct a practical device for the purpose intended, not departing from the spirit of the invention and within the scope of the appended claims.
I claim: 1. In a device of the described, a hub,
an elongated c lindrical shell transversely,
mounted on the ub, a pair of propeller blades with rounded inner end portions journaled in the said shell, the said rounded inner end portions havi channels in one side and having bores opening out into the said channels, journals on the same ends of the said pro peller blades, the journal of each blade being journaled in the bore of the other blade, and means for rotating the blades on their longitudinal axis.
2. In a device of the kind described, a hub,
, ail elongated receptacle transversely mounted of the bl on the hub, a pair of ropelle'r blades, the
inner end portion of can blade bein rounded and journaled through the ends 0 the said receptacle, the said inner rounded ends of the blades withinthe receptacle having an lar channels apart of their len th, the remainder es being roun ed and extended angularly inward toward the axis of the blades to terminate in axially extended journals, the said bladw also having axially extended bores opening out into the said channels for the reception of. the journals of the oppositely disposed blades, and means whereby the blades may be independentl rotated on their longitudinal axis to vary their relative pitch.
3. In a device of the kind described, in combination with the drive shaft of an en gme, a hub mounted on the said drive shaft, an elongated c lindrical receptacle transversely mounte on the said hub propeller blades ournaled in the ends of the said receptacle, each of the said blades having an axially ahgned journal and bore for reception of the bore and the o posite blade.
4. a device of the kind described, in combination with the drive shaft of an engine, the said drive shaft having a longitudinal bore openin out through its end and havin diametrica y opposite slots through journal respectively of its wa near the inner end of the said bore ing the said connecting rods to the studs onthe propeller blades, a bearing slidably mounted on the said drive shaft over the slots therein, the inner race of the said bearing being connected to the inner end of the slide rod through the said slots, and manually operable means for shifting the said bearing lon 'tudinall ter ering with its rotation.
5. In a device of the kind described, a pair of mated propellers including the shanks and blades, the inner end of each shank bein cut away 'and formed with an axially alifie journal at its-extremity and a bearing re spaced from; the said journal, the intermediate portion of each shank being channeled and cut out longitudinally and an larly so as to permit the two said oppose journals of the radially assembled pro llers, to enter the two said opposed bores, w ereby the twopropellers may oscillate inde ndently upon their axis to varytheir pitc and yet will mutually support one another against torque. In testimony whereof I aflix my si ature.
. ROY F. WOO EN.
on the drive shaft without in- I
US435070A 1930-03-12 1930-03-12 Adjustable and reversible propeller for aeroplanes or other aircraft Expired - Lifetime US1806325A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2442691A (en) * 1942-03-24 1948-06-01 Rotol Ltd Aircraft propeller
US2480521A (en) * 1945-03-16 1949-08-30 Joseph R Thompson Power drive and control mechanism
US5017090A (en) * 1988-03-28 1991-05-21 Morrison Douglas M Variable pitch propeller blades and drive and adjusting mechanism therefor
US5102301A (en) * 1988-03-28 1992-04-07 Morrison Douglas M Variable pitch propeller blades, hub and drive and adjusting mechanism therefor
US5104291A (en) * 1988-03-28 1992-04-14 Morrison Douglas M Variable pitch propeller blade hub and drive and adjusting mechanism therefor

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2442691A (en) * 1942-03-24 1948-06-01 Rotol Ltd Aircraft propeller
US2480521A (en) * 1945-03-16 1949-08-30 Joseph R Thompson Power drive and control mechanism
US5017090A (en) * 1988-03-28 1991-05-21 Morrison Douglas M Variable pitch propeller blades and drive and adjusting mechanism therefor
US5102301A (en) * 1988-03-28 1992-04-07 Morrison Douglas M Variable pitch propeller blades, hub and drive and adjusting mechanism therefor
US5104291A (en) * 1988-03-28 1992-04-14 Morrison Douglas M Variable pitch propeller blade hub and drive and adjusting mechanism therefor

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