US2495453A - Feathering propeller, hub, and coupling - Google Patents

Feathering propeller, hub, and coupling Download PDF

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Publication number
US2495453A
US2495453A US69288A US6928849A US2495453A US 2495453 A US2495453 A US 2495453A US 69288 A US69288 A US 69288A US 6928849 A US6928849 A US 6928849A US 2495453 A US2495453 A US 2495453A
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hub
shaft
blades
rack
propeller
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US69288A
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Herreshoff Algernon Sidne Wolf
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63HMARINE PROPULSION OR STEERING
    • B63H3/00Propeller-blade pitch changing
    • B63H3/02Propeller-blade pitch changing actuated by control element coaxial with propeller shaft, e.g. the control element being rotary
    • B63H3/04Propeller-blade pitch changing actuated by control element coaxial with propeller shaft, e.g. the control element being rotary the control element being reciprocatable
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63HMARINE PROPULSION OR STEERING
    • B63H3/00Propeller-blade pitch changing
    • B63H2003/004Propeller-blade pitch changing comprising means for locking blades in position

Definitions

  • Another objectof'ithe invention is to utilize the .7 urination :of the :spindle in such a :fashion vthat ritqservesto hold the spindle intoithe :hub and al- -so provides the operating mechanism for varying the pitcho theblade.
  • Figure 1 is a sectional .View largely -diagram matic illustrating .theiinstallation of this .invenin .a 'vessel and fshowing the propeller, its #driving-shaft and blade-shifting mechanism.
  • .Figui-e3 is :a plan view of -the flexible-belt to which the shifting Jever on they propeller vshaft is peller-shaft and the Operatinjgfmechanism for the vpropolier-blades Tigm-el. is -a Vsectionalview through the hub of the propeller With'th'e "blades omitted.;
  • Figure 8 is a sectional view on line twg-'8 of Fig- ⁇ Figure .9 isa View of the spindle of one of the propeller blades which .is :shown fragmentally;
  • Figure l0 is an end view of Figure 9;
  • Figure 12 isian end view of the structure of Figure 411.
  • Figure 13 is asection-al View on line
  • I provide a propellerhub with a central Vaxial bore for receiving the poW-ershaft, and in a pla-ne at right vangles rto this axial bore an-d symmetrically displaced .from the bore, yI provide .a plurality vof threaded bores so as to intersect the central bore .offset Vfrom V.the Ycenter thereof.. .Blades ⁇ having spindles which are threaded are screwed into :these different .bores in .sucha manner that they may be rotated .about their axes rather freely.
  • the spindles are each provided with teeth eX- tending across .their threads and a .rack which is .common .to all .of .the spindles has'teeth to enn .gage .the teeth-on the spindles, vs0 thatas the rod, upon Whichthe .rack is mounted, is moved axially and .at right angles vto .the plane in which the threaded bores .are located,-the..blade spindles Will i berotated in the bores to vary the pitch of the propeller.
  • Thisrack also-serves to prevent the spindles and their blades .from being disengaged from the threaded bores by a rotary movement to unscrew .themthereirom.
  • the removal, hovvever is made very simple by merely moving the rack a suflcient extent to disengage the teeth of the spindles wheny they may be readily removed from the hub of thepropeller by unscrewingthem from their threaded bores.
  • Anysuitable means may be provided for moving the rack, and I have here lshovvna mechanical means which is manually .operated from the cockpit or ⁇ pilot position of the vesselin which the apparatus is installed.
  • the hull of the vessel in which this apparatus is installed is des- 3 threaded bores see Fig. 7) which are shown as three in number in this illustration of the invention, each of which bores intersects the bore 23 as more clearly shown in Figure 7.
  • the center of the axis of this bore 25 is oiset from the central axial bore, as also shown in this figure.
  • This spindle extends from one side of the blade 26 so that the portion 29 of the blade (see Fig. 8) will extend inwardly over the hub so that the center line of the blade will be substantially radial of the hub.
  • the threading of the spindle 21 into the bore 25 is such that the blade may freely rotate in this threaded mounting yas' a bearing.
  • the spindles 21 are each also provided with teeth 30 (see Figure 10) over a certain arcuate extent of the spindle to form in effect a mutilated gear in which the teeth extend but a portion of the circumference thereof, it being only necessary for the operation of the blade that the teeth extend over a sufficient arc to operate the blade from a pitch for giving forward movement to a pitch to giving reverse movement and with a feathering of the blade in either a position at right angles to the axis of rotation of the propeller or at ninety degrees therefrom and in a plane passing radially through the axis of the propelling shaft.
  • having three sets of teeth 32 is formed on the end of a rod 33 which extends through the hollow shaft 24 and is located in engagementwith each of the three sets of teeth on the spindle 21, as shown in Figures 6 and 8, so that should the rod 33 be moved axially of the shaft 24 and relative thereto, the blades would be simultaneously rotated about their axes in their bearing mounting in the hub 22, so as to simultaneously adjust the pitch of all their blades.
  • This rack also serves to lock each of the blades in its threaded bore as when the rack is in en gagement with the teeth of the spindle, the spindle cannot rotate without movement of the rack: thus, if the rack is held against movement, the blades cannot be removed from their hub ⁇
  • This arrangement also provides for a very easv removal of the blades from their hub as the rack may be moved beyond engagement with the teeth in either an inward or an outward direction bv which disengagement of the teeth from the rack will permit the blades to be each easily removed bv unscrewing the same from the threaded bore 25 and a replacement of another blade, should occasion reduire.
  • the hub also comprises a chamber 35 which is threaded onto the aft side of the solid hub 22 as at 26 and provides a grease chamber 31 having a piston 4
  • This housing 35 is provided with an opening 4
  • An abutment 42' isprovided for the spring 39 and the guiding portion 42 of the piston may pass freely through this abutment 42' as the piston moves.
  • A. fitting 59' is providedon casing 5P. for charging the system with grease.
  • Grease enters the case 59 and the hollow shaft 24 and forces the piston 4f! back to provide a reservoir of grease until vent e! is uncovered.
  • At first air will es- ⁇ cape at vent 4
  • Bv this arrangement all moving parts 'are embedded in grease and no water mav get to them.
  • the hollow drive shaft 24 is, of course, fixed to the collar 43 of the hub 22 at its outboard end and extends inwardly over such extent as may be required to obtain driving connection from the engine.
  • the inboard end 45 of the drive shaft 24 is keyed to the sleeve 46 of a coupling designated generally 41, such key being designated as 48.
  • 'I'he other end of this sleeve 46 is flanged as at 49v and connected to the flange I8 of the enginedrive shaft by means of bolts 5D, so that as rotation'v of the engine occurs, rotation of the drive shaft 24 and hub 22 will, also, occur.
  • the sleeve 46 is bound to the shaft 24 by means of the clamp (Fig. 13) having its bolts 5
  • the sleeve 46 is provided with diametrically opposite slots 55 through which a cross pin 56 extends and enters a ring 63 which is supported at either side by ball bearings 51 and 58, which are slidably mounted Aon the outer surface of the sleeve 46.
  • a slidable casingv 59 embraces these ball bearings and the ends of the pin and include supporting blocks 6
  • The'pinV 56 extends through a cross head 64 'which has a collarl 65 extending therefrom threadingly engaging the end of the rod 33 as at 66.
  • the housing 59 has'trunnions 61 extending outwardly therefrom upon which there'is mounted the bifurcated'arms 68 of a' lever 69 by set screws
  • the lever BS' is moved about the fulcrum 1
  • the lever 69 (see Figure 1) ⁇ is connected to an endless belt or chain 15 as 'at 16, which chain is mounted about sprockets 11 and 18' soV that as the chain is moved in one direction or the other, the lever 69 will be swung about its fulcrum 1
  • sprocket 1 8 isA fixed on the end of shaft 8
  • a hub 84 At the upper end of this shaft 8
  • This handle 85 has a dog 81 which swings over a quadrant 88 with notches 89 therein, as shown more particularly in Figure 4, so that the movement of the shaft 8
  • the various notches 89 may be set to provide the various different positions which itis ydesired the propeller .shall be adjusted to.
  • the propel- 1er blade may be set to feather when not rotating for leas-t resistance of movement of the vessel through the water by having the blades in planes radial and through the axis of the propeller shaft, or the blades may be set at right angles to the axis of the propeller shaft when no movement is desired, but yet the hub is rotating.
  • Other inter- Amediate positions for either forward propulsion or reverse propulsion may be also provided and the notches may be adjusted to the positions .found most eicient and satisfactory in connec- 5 a central axial bore receiving said shaft in a.
  • a plurality of threaded bores symmetrically displaced in said hub and intersecting said central axial bore, with thebire centerlines oifs'etkfrom that of said central*r ifial bore, a plurality of blades with theirf blade spindles threaded into said'bores for rotational motion about their centerlines, teeth formed-in the surface of-said spindles extending lengthwise thereof acrossfslaid threads and a rack injk'sa'id central bore engaging said teeth of the spindles and means for-moving said rack axially ofthe power shaft tofvrotate the blades in their boresg' 2.

Description

Jan. 24, 1950 A. s. DE w. HERREsHor-'F FEATHERING PROPELLER, HUB, AND COUPLING 2 Sheets-Sheet 1 Filed Jan. 5, 1949 All A7 7DRNEYS.
Jan. 24, 1950 A. s. DE w HERREsHoFF 2,495,453
FEATHERING PROPELLER, HUB, `ND COUPLING 2 Sheets-Sheet 2 Filed Jan. 5, 1949 v INVENToR. /gezwa/z S10/nay e/Vo//He/reso Patented Jan. 24, 1950 :STATES .PATENT oFFICE PROPELLER, HUB, COUPLING Sidney De Wolf HerreshofLBristol, B. I.
`ilpplicaton January 5, 1949,1SerialN'o.69,288
ioontrol.
.Another object of l:the .invention is to provide 9 Claims. (Cl. F10-160.23)
lo l'Oneof the lobjects"lofthis..inventionis to pro-l 'ivide .amore simple construction of blade pitch .in .propeller lhub with blades `so'mounted thereinfg5 they may abe `easily removed and replaced :willen"required :Another .object of vthe invention Lis to provide the spindle 'of thepropellerlala-de with means so 4tl'fat when its ,pitchioperating mechanism 'en-s gages it, :it will ibe .locked in e place.
Another objectof'ithe invention .is to utilize the .7 urination :of the :spindle in such a :fashion vthat ritqservesto hold the spindle intoithe :hub and al- -so provides the operating mechanism for varying the pitcho theblade.
.Another objectof `the-.invention .is r to prevent awater contacting the moving-.parts by embedding utle-partsin grease.
With these and other fobjectsin view, -the invention-consists ofcertain novel features of con- .stnuctiom `as will befxnore ully :described and par- 'vtieularly 'pointed out in lthe appended claims.
In .the accompanying drawingsz .Figure 1 is a sectional .View largely -diagram matic illustrating .theiinstallation of this .invenin .a 'vessel and fshowing the propeller, its #driving-shaft and blade-shifting mechanism.
Figure 2-.is.asectional view through the manina): :control column;
.Figui-e3 is :a plan view of -the flexible-belt to which the shifting Jever on they propeller vshaft is peller-shaft and the Operatinjgfmechanism for the vpropolier-blades Tigm-el. is -a Vsectionalview through the hub of the propeller With'th'e "blades omitted.;
g Figure 8is a sectional view on line twg-'8 of Fig- `Figure .9 isa View of the spindle of one of the propeller blades which .is :shown fragmentally;
Figure l0 is an end view of Figure 9;
Figure ll -isianelevational View of the end of the rack for engaging land operating the propeller blades; A
Figure 12 isian end view of the structure of Figure 411; and
Figure 13 is asection-al View on line |3-I3 of Figure 6.
In proceeding withfthis invention, I provide a propellerhub with a central Vaxial bore for receiving the poW-ershaft, and in a pla-ne at right vangles rto this axial bore an-d symmetrically displaced .from the bore, yI provide .a plurality vof threaded bores so as to intersect the central bore .offset Vfrom V.the Ycenter thereof.. .Blades `having spindles which are threaded are screwed into :these different .bores in .sucha manner that they may be rotated .about their axes rather freely. The spindles are each provided with teeth eX- tending across .their threads and a .rack which is .common .to all .of .the spindles has'teeth to enn .gage .the teeth-on the spindles, vs0 thatas the rod, upon Whichthe .rack is mounted, is moved axially and .at right angles vto .the plane in which the threaded bores .are located,-the..blade spindles Will i berotated in the bores to vary the pitch of the propeller. Thisrack Aalso-serves to prevent the spindles and their blades .from being disengaged from the threaded bores by a rotary movement to unscrew .themthereirom. The removal, hovvever, is made very simple by merely moving the rack a suflcient extent to disengage the teeth of the spindles wheny they may be readily removed from the hub of thepropeller by unscrewingthem from their threaded bores. Anysuitable means may be provided for moving the rack, and I have here lshovvna mechanical means which is manually .operated from the cockpit or `pilot position of the vesselin which the apparatus is installed.
With reference .to the drawings, the hull of the vessel in which this apparatus is installed is des- 3 threaded bores see Fig. 7) which are shown as three in number in this illustration of the invention, each of which bores intersects the bore 23 as more clearly shown in Figure 7. The center of the axis of this bore 25 is oiset from the central axial bore, as also shown in this figure.
Blades 26, each having a spindle 21, threaded as at 28, threadingly engage the bores 25. This spindle extends from one side of the blade 26 so that the portion 29 of the blade (see Fig. 8) will extend inwardly over the hub so that the center line of the blade will be substantially radial of the hub. The threading of the spindle 21 into the bore 25 is such that the blade may freely rotate in this threaded mounting yas' a bearing. The spindles 21 are each also provided with teeth 30 (see Figure 10) over a certain arcuate extent of the spindle to form in effect a mutilated gear in which the teeth extend but a portion of the circumference thereof, it being only necessary for the operation of the blade that the teeth extend over a sufficient arc to operate the blade from a pitch for giving forward movement to a pitch to giving reverse movement and with a feathering of the blade in either a position at right angles to the axis of rotation of the propeller or at ninety degrees therefrom and in a plane passing radially through the axis of the propelling shaft.
A rack 3| having three sets of teeth 32 is formed on the end of a rod 33 which extends through the hollow shaft 24 and is located in engagementwith each of the three sets of teeth on the spindle 21, as shown in Figures 6 and 8, so that should the rod 33 be moved axially of the shaft 24 and relative thereto, the blades would be simultaneously rotated about their axes in their bearing mounting in the hub 22, so as to simultaneously adjust the pitch of all their blades. This rack also serves to lock each of the blades in its threaded bore as when the rack is in en gagement with the teeth of the spindle, the spindle cannot rotate without movement of the rack: thus, if the rack is held against movement, the blades cannot be removed from their hub` This arrangement also provides for a very easv removal of the blades from their hub as the rack may be moved beyond engagement with the teeth in either an inward or an outward direction bv which disengagement of the teeth from the rack will permit the blades to be each easily removed bv unscrewing the same from the threaded bore 25 and a replacement of another blade, should occasion reduire.
The hub also comprises a chamber 35 which is threaded onto the aft side of the solid hub 22 as at 26 and provides a grease chamber 31 having a piston 4|! pressed by spring 39 and held against leakage bv O ring 38 to keen the rack and teeth of the spindle lubricated, This housing 35 is provided with an opening 4| on the opposite side of the piston so that no fluid will be trapped in the chamber as the piston operates. An abutment 42' isprovided for the spring 39 and the guiding portion 42 of the piston may pass freely through this abutment 42' as the piston moves.
A. fitting 59' is providedon casing 5P. for charging the system with grease. Grease enters the case 59 and the hollow shaft 24 and forces the piston 4f! back to provide a reservoir of grease until vent e! is uncovered. At first air will es-` cape at vent 4| but when the system is sufficiently charged grease will appear. Bv this arrangement all moving parts 'are embedded in grease and no water mav get to them.
The hollow drive shaft 24 is, of course, fixed to the collar 43 of the hub 22 at its outboard end and extends inwardly over such extent as may be required to obtain driving connection from the engine. In this particular showing, the inboard end 45 of the drive shaft 24 is keyed to the sleeve 46 of a coupling designated generally 41, such key being designated as 48. 'I'he other end of this sleeve 46 is flanged as at 49v and connected to the flange I8 of the enginedrive shaft by means of bolts 5D, so that as rotation'v of the engine occurs, rotation of the drive shaft 24 and hub 22 will, also, occur. The sleeve 46 is bound to the shaft 24 by means of the clamp (Fig. 13) having its bolts 5| extending through recesses in the shaft 24 as the sections 52 are drawn down into position about the end of the sleeve 46.
The sleeve 46 is provided with diametrically opposite slots 55 through which a cross pin 56 extends and enters a ring 63 which is supported at either side by ball bearings 51 and 58, which are slidably mounted Aon the outer surface of the sleeve 46. A slidable casingv 59 embraces these ball bearings and the ends of the pin and include supporting blocks 6|]v vand end caps 6| held to the casing 59 by bolts 62; The'pinV 56 extends through a cross head 64 'which has a collarl 65 extending therefrom threadingly engaging the end of the rod 33 as at 66.
The housing 59 has'trunnions 61 extending outwardly therefrom upon which there'is mounted the bifurcated'arms 68 of a' lever 69 by set screws |51 which has these arms68 slotted as at 18 so as to engage a fulcrum 1| supported at the outer ends of legs 12 on the bracket 13 mounted on the engine |1. ThusQas the lever BS'is moved about the fulcrum 1|, the casing 59 with the pin 56 will be moved axially of the drive shaft 24 so as to move the rod 33 and in turn the rack and blades of the propeller to adjust their pitch.
The lever 69 (see Figure 1)` is connected to an endless belt or chain 15 as 'at 16, which chain is mounted about sprockets 11 and 18' soV that as the chain is moved in one direction or the other, the lever 69 will be swung about its fulcrum 1|. In order to move this chain, sprocket 1 8 isA fixed on the end of shaft 8| which is rotatably mounted in the column 82 which extends up through the 'cockpit deck I6 and is secured thereto by a flange 83. At the upper end of this shaft 8|, there is a hub 84 having a handle 85 hinged as at 86 thereto so as to rotate the shaft and consequently the gear 18 for manipulation of the lever 69. This handle 85 has a dog 81 which swings over a quadrant 88 with notches 89 therein, as shown more particularly in Figure 4, so that the movement of the shaft 8| may be locked lin any Vone of a plurality of positions. In this manner,
the various notches 89 may be set to provide the various different positions which itis ydesired the propeller .shall be adjusted to. Thus, the propel- 1er blade may be set to feather when not rotating for leas-t resistance of movement of the vessel through the water by having the blades in planes radial and through the axis of the propeller shaft, or the blades may be set at right angles to the axis of the propeller shaft when no movement is desired, but yet the hub is rotating. Other inter- Amediate positions for either forward propulsion or reverse propulsion may be also provided and the notches may be adjusted to the positions .found most eicient and satisfactory in connec- 5 a central axial bore receiving said shaft in a. portion thereof, a plurality of threaded bores symmetrically displaced in said hub and intersecting said central axial bore, with thebire centerlines oifs'etkfrom that of said central*r ifial bore, a plurality of blades with theirf blade spindles threaded into said'bores for rotational motion about their centerlines, teeth formed-in the surface of-said spindles extending lengthwise thereof acrossfslaid threads and a rack injk'sa'id central bore engaging said teeth of the spindles and means for-moving said rack axially ofthe power shaft tofvrotate the blades in their boresg' 2. The combination as in claim 1 wherein said rack is mountedfor movement out of the spir'idle teeth to permitfremoval by unthreading` v` the spindles of thei blades from the threaded bores. 3. The combination as in claim 1 whereinrthe centerlines ofi said axial bores are all in(y "the same plane at right angles to the axis ofmthe central bore. 4. The combination as in claim 1 wherein said power shaft is'h"llow and the means for moving the rack is a rodv extending therethrough. A 5. The combination as in claim 1 wherein said power shaft is hollow and the means for moving y attracts the rack is a rod extending therethrough, and said rod being connected to a pin in a slot in the shaft with a casing slidable over the slot and pin movable by sliding the casing along the shaft.
6. The combination as in claim 1 wherein posi- 'tive means are provided for maintaining the system charged with lubricant to exclude water therefrom.
7. The combination of claim 1 wherein said power shaft is hollow, said means for moving the rack extends through said hollow shaft and means is provided for lling the hollow shaft and system connected therewith with grease-:` to exclude water from the operating parts.
8. The combination of claim 1 wherein a grease reservoir is in communication with the operating parts of said system. j
9. The combination of claim 1 wherein a grease reservoir is in communication with the operating parts of said system and a spring pressed plunger urges grease from said reservoir about the operating parts.
ALGERNON SIDNEY DE WOLF HERRESHOFF.
No references cited.
US69288A 1949-01-05 1949-01-05 Feathering propeller, hub, and coupling Expired - Lifetime US2495453A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3211235A (en) * 1964-02-17 1965-10-12 Enstrom Corp Control system for yaw control rotors of helicopters
US3262502A (en) * 1964-05-28 1966-07-26 Harry J Nichols Manual controllable pitch propeller systems for motorboats
US3552348A (en) * 1968-04-27 1971-01-05 Kiyoshi Shima Marine propulsion drive

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3211235A (en) * 1964-02-17 1965-10-12 Enstrom Corp Control system for yaw control rotors of helicopters
US3262502A (en) * 1964-05-28 1966-07-26 Harry J Nichols Manual controllable pitch propeller systems for motorboats
US3552348A (en) * 1968-04-27 1971-01-05 Kiyoshi Shima Marine propulsion drive

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