US1887146A

US1887146A - Adjustable propeller

Info

Publication number: US1887146A
Application number: US510423A
Authority: US
Inventors: De Witt C Conkling
Original assignee: Individual
Current assignee: Individual
Priority date: 1931-01-22
Filing date: 1931-01-22
Publication date: 1932-11-08
Anticipated expiration: 1949-11-08

Description

Now 8, 1932'. DE WlTT c. CONKLING ADJUSTABLE PROPELLER Filed Jan. 22, 1931 4 Sheets-Sheet 1 4-: 1I[ INVENTOR l-ATOR Nov. 8, 1932. DE W|TT c. CONKLING 1,387,145

' ADJUSTABLE PROPELLER Filed Jan. 22, 1951 4 Sheets-Sheet 2 INVENTOR Nov. 8, 1932. DE WlTT c. CONKLING 1,

ADJUSTABLE PROPELLER Filed Jan. 22, 1951 4 Sheets-Sheet 5 INVENTOR Nov. 8, 1932. 01% WlTT c. CONKLING 1,837,146

ADJUSTABLE PROPELLEYR Filed Jan. 22, 1931 4 Sheets-Sheet 4.

into a'feathering or reversed Patented Nov. 8, 1932 PATENT OFFICE DE WITH? 0. CONKLING, 0! LONG ISLAND, NEW YORK ADJUSTABLE PROPELLEB Application filed January 22, 1931.; Serial No. 510,423.

This invention relates to an peller, and while the invention is capable of use in the construction of propellers for various purposes, it is particularly adapted for use upon aeroplanes, and the like.

An object ofthe invention is to provide a propeller and operating mechanism therefor, all constructed and corelated to provide for the easy and accurate change of pitch of the propeller blades from aremote control as for instance from a control located at the drivers seat in an aeroplane.

A more specific object is to provide against the likelihood of any loose play of the propeller blades with respect to their mountings and operating mechanism. A I

A further object is -to provide in combination an adjustable propeller, an engine for driving said propeller, a remote control for the propeller, and connections between the propeller and the remote control extending in a substantially straight line through the engine at the axis of rotation of the propeller.

A further object is to provide an improved,

efiicient and accurate form of control whereby to adjust the blades of an adjustable propeller.

Afurther object is to rovide means to prevent the accidental ad ustment of the propeller into a reverse angular position without the definite intent on the part of the operator so to do. v

A further object is to rovide means for preventing adjustment of t e propeller blades position except when the speed of the engine has been reduced to desirable degree. 7

A further object is to provide means automatically operable to reduce the engine speed in the ei'ent that efiort is made by the operator to reverse thepropeller blades without having previously manually reduced the engine speed. p

A further objectis to provide means normally effect-iveto prevent attainment of a too great engine speed when the propeller blades are in a reversed position but capable of permitting, manual control of the engine speed to max mum in an emergency.

A further object is to provide means to adjustable propermit starting of the engine at low speed irrespective. of the position of the propeller blades but normally efiective to prevent any considerable engine speed except when, or until, the propeller blades are in their;normal or non-reversed position.

A further object is to provide means effective when the blades are in a reversed position to limit the speed at which the engine may normally be run in proportion to the angular position of the propeller blades.

A further object is to so construct the control mechanism that it will be freely operable by the manual manipulation of a single operating handle, and so that said handle and hence the propeller blades, will stand definitely in any position to which they are adjusted by the operator.

A further object is to provide means gperable automatically to change the pitch 0 the pro eller blades dependent upon the altitude of t e apparatus above the earth.

Other objectsand aims of the invention, more or less specific than. those referred to above, will be in part obvious and in part pointed out in the course of the following escription of the elements, combinations, arrangements of parts and applications of principles constituting the invention; and the scope of protection contemplated will be Il'ldicated in the appended claims.

In the accompanying drawings which are to be taken as a part of this specification, and in which I have shown merely a preferred form of embodimentof the invention Fig. l'is a perspective view of-the forward portion of an aeroplane fitted with a reversible propeller and operating mechanism therefor constructed in accordance with this invention. I

-Fig.-2 is an enlarged vertical sectional view of the mechanism illustrated in Fig. 1. Fig. 3 is a vertical sectional view approximately upon the plane of line I II'1II of Fig. .2, parts being shown in elevation for clearness of disclosure.

Fig. 4 is a top plan view of the hub portion of the blade carrier shown in Fig. 3. v

Fig. 5 is a vertical sectional view illustrat-' ing a modified arrangement in which an lit) trating a modified engin nism.

Fig

8 is a vertical sectional view upon the plane of line VIII-VIII of Fig. 7, and

Fig. 9 is a diagrammatic development of parts appearing in Figs.' 7 and 8.

Referring to the drawings for describing in detail, the structures as illustrated therein, the reference character L indicates the forward portion of an aeroplane. The propeller drive shaft G projects centrally from the structure L in the usual manner and carries the propeller blades H-H. I

The mannerof connecting the propeller blades with the. shaft which is rigidly connected to the projecting end of the shaft, as by means of a retaining nut 2, the sleeve being held against rotation upon the shaft by a suitable means such as the feathers 3. A pair ofstud shafts as 4 and 5 are formed upon this sleeve projecting in diametrically opposite directions therefrom, being rigid with the sleeve and hence with the shaft G. The propeller blades are mounted upon these stud shafts so as to .be

rotatable within limits upon said shafts. Each propeller blade has a sleeve 6 which fits over the respective stud shaft, and asuitable retaining nut or the like as? carried at the outer end of the stud shaft is positioned in opposition to an annular shoulder 8 provided interiorlygfthe sleeve so that'the sleeve is held by said nut against movement endwise of the stud shaft. A suitable anti-friction bearing thrust device as 9 is preferably interposed between the nut and the shoulder 8 to facilitate ease of rotation of the sleeve upon the stud shaft under the excessive thrust strains which occur due to centrifugal force when the propeller blades are being rapidly swung about with the shaft G in use.

If desired each of the sleeves 6 maybe additionally provided with an annular-interior groove 10 to fit about an annular rib 11 of the respective stud shaft for further.

guarding against endwise movement of the sleeve 111 use.

In order to vfac'litate application of the sleeves 6 onto the studsh'afts said sleeves are herein shown as each beingformed in two generally semimylindrical parts held together by clamp devices 12-12. These clamp devices are held in position about the sleeves by means of suitable lock nuts or the G includes a sleeve 1.

stance illustrated the pinion as like as 13 and may therefore be readily attached or removed as may be required to facilitate the attachment and removal-of the sleeves upon the stud shafts.

The manner of attaching the sleeves upon the ends of the propeller blades H may take I any form but as illustrated herein the sleeves project beyond the end of the stud shafts 4 and 5 and the propeller blades are clamped between the two halves comprising the projecting portion. The propeller blades have one or more annular ribs as 1a thereon re-- ceived within annular grooves 15 interiorly of the sleeves, and additional clamp elements as 16 are positioned about that portion of the sleeve which envelopes the blade. It is noted that the portions of the sleeves which surround the end of the propeller blades are of such size that when the clamp elements 16 are clamped tight upon the sleeve then the halves of the sleeves are likewise tightly engaged upon the blades so that the blades and sleeves are non-rotatable with respect to each other.

The clamp devices 16 are held by lock nuts or the like 17 and are therefore readily attachable and detachable to facilitate attachment and removal of the sleeves from the blades, and from the stud shafts, when required.

The sleeve 6 of each blade is formed at its ilmer end witha segmental pinion projecting at one side thereof, the teeth being disposed concentric with the axial center line of the stud shafts. The sleeves are positioned upon their respective stud shafts so that the pin ions project in diametrically opposite directions with respect to said centre line. In the in- 18 of the sleeve which is mounted upon the stud shaft 4 projects downwardly while the pinion as 19 of the sleeve which is mounted upon the stud shaft 5 projects upwardly.

These segmental pinions 18 and 19 are of course positioned at opposite sides of the axial centre line of the main drive shaft G.

' Slidably mounted upon the shaft Gr, and

preferably upon a tubular extension as 20 of tension 20 by suitable means such as the feathers 24 as will be readily understood.

From this arrangement it will be seen that shdingmovement of the sleeve 21, operating is positively held through the rack bars and segmental pinions,

will produce a rotary movement of thepro-.

ller blades-in opposite directions so that the thrust angle of the bladesis thereby readshaft and within this cavity is a pair of coil,

springs as 26-and 27 coiled about the stud shaft. The spring 26 is formed at one-of its ends with a hook 28 which engages about a pair of pins as 29 and 30. These pins stand normally aligned with each other radially .of the pin shaft, the pin 29 being carried rigid with the pin shaft 5 and the pin 30 being carried rigid with the sleeve 6, and it will be noted that the hook 28 is of a width to engage both of said pins so thatrotary movement of the sleeve 6 for instance in a clock-wise direction about the shaft 5 will cause the hook to be moved by the pin 30 away from the pin 29 thereby tensioning the spring 26, while rotation of the sleeve 6 in the opposite or contraclockwise direction will simply move the pin 30 away from the hook leaving the hook rest- .ing against the pin 29.

The opposite end of the spring 26 is fixed to the shaft 5 as at 31 in any suitable manner, and it will be understood that the spring is at all times under a desirable degree of tension.

The spring 27 is formed at one of its ends with a hook as 32 facing circumferentially in an opposite direction as compared with the hook 28. Thehook 32 engages about a pair of pins as 33 and 34 which stand normally aligned with each other radially of the pin shaft, the pin 33 being carried rigid with the pin shaft and the pin 34 being carried' rigid with the sleeve 6. The hook 32 is of a width to engage both of said pins 33 and 34 so that rotary movement of the sleeve 6 for instance in a'contra-clockwise direction about turn said sleeve in one direction and the other the shaft will cause the hook to be moved by the pin 34 away from the pin 33 thereby tensioning the spring 27, while rotation of the sleeve 6 in the opposite or clock-wise direction will simply move the pin 34 away from the hook leaving the hook resting against the pin 33. i

The opposite end of the spring 27 is fixed to the shaft 5 asat 35 in any suitable manner, and it will be understood that the spring is at all times under a desirable degree of ten- 4 sion.

According to this arrangement the

springs

26 and 27 exert resilient pressure in opposite directions against the sleeve 6, one tending to tending to turn it in the opposite direction. The

pins

29 and 33 constitutecentering means by which a normal intermediate position is defined for the sleeve thereby holding the sleeve against unintentional rotation upon its carrying shaft 5 and approximately in a position which is preferably the normal, or most venient position within the areoplane, as for,

instance adjacent the drivers seat, and a flexible driving shaft as 37 extending from said handle to adjacent the sleeve 21. The

sleeve 21 has a collar 38 rotatable in an annular groove thereon and formed with suitable lugs 39 which are engaged by yoke arms 40. The arms 40 are pivotally mounted upon a pivot shaft 41 at one side of the drive shaft G and have a segmental rack 42 fixed thereto which is engaged by a small pinion 43 fixed upon a shaft 44. The shaft 44 has a larger pinion 45 fixed thereon engaging with the teeth of a worm 46 directly actuated by the flexible shaft 37.

Rotation of the handle 36 will thus swing the oke arms and thereby move the sleeve 21 bacl and forth at the will of-the operator.

Reduction gears or other apparatus as may be desired may be interposed between the handle 36 and the shaft 37, as indicated at 47, whereby the blades from the handle 36.

In the modification Figs. 5 and 6 the two rack bars 48 and 49, corresponding respectively with the two rack bars22 and 23 heretofore described, instead of being connected with a collar slidable upon the. sleeve 20, are connected with a body piece 50 which is in turn rigidly mounted upon the outer endof a slide rod 51 longitudinally slidable within a required to rotate with the engine shaft 3 as is the forward end portion of said shaft. The f -rtion 57 may be held against rotation at all tunes by suitable means such for instance as by means of the stationary pin 58 slidable through a laterally projecting lug 59 of said sleeve, the shaft being thus permitted longitudinal movement but without rotation.

The inner end of the portion 57 is threaded 'as at 60 and a. threaded collar 61 engages to facilitate the easy operation 'of 7 51 said shaft is split and is connected together by an anti-friction connection as 56 so that its rear end portion as 57 is not thereabout having a gear 62 fixed thereto by which it maybe rotated as-by means of the pinion 63 which is carried upon the pivot shaft 6& of the handle 55. A suitably marked stationary dial as 65 may be provided concentric with the pivot shaft 64 to assist the operator in determining the position of his propeller blades by means of the handle 55, and a sutable friction device as 66 may be carried by the handle for engaging against the surface of the dialplate to hold the handle against unintentional movement at all times.

These parts are allmounted upon a suitable support 67, such as the instrument board or other stationary element of aeroplane construction adjacent the drivers seat.

It will be seen that movement of the handle 55 around the dial will rotate the threaded sleeve 61 and thereby move the shaft 51-57 slidably through the engine shaft 53 and alter the angularposition of the propeller blades in one direction or the other according to the direction, and in the amount, in which the handle 55 has been moved.

The engine 54 may be of any desired construction providing for passage of the slide shaft 51-57 therethrough centrally of the axis of rotation of the propeller blades with the engine shaft, but for the purpose of illustration herein said engine is'indicated asbeing of the type fully illustrated and described in pending application Serial No. 477,242 which includes essentially a series of power cylinders as 68 radiating from the central drive shaft 53, being carried upon a housing as 69 within which the drive shaft is rotatably mounted. Connecting rods as 70 project from the cylinders into the housing and have driving connection with a pair'of cam discs as 7l71 mounted upon the drive shaft so that operation of the pistons as 72 within the cylinders will cause rotation of the cam discs and conse uent rotation of the shaft 53.

ny suitable means, such as the feather 73 may be employed for insuring rotation of the slide rod 51 with the shaft 53 at all times.

In Figs. 7, 8 propeller blade operating mechanism which may be employed in association with the mechanism heretofore described, and particularly in association with the operating handles 36 or 55 above described. In these figures the operating handle is indicated by the reference character 74. The shaft or rod by which this handle is connected with the propeller blades for changing the pitch of the propeller blades is indicated by the reference character 75, and it is noted that while this shaft 75 is shown as having aithreaded connection at its end with a gear 76, corresponding with the gear 62 illustrated in Figs.

5 and 6, for producingan' endwise sliding movement of the shaft 7 5 to change the pitch of the propeller blades in the manner ind:-

cated in Fig. 5, nevertheless the shaft 75 may and 9, there is illustrated a P equally well be considered as having fixed connection with the gear 76 to thereby produce rotary movement of said shaft with said gear so as to change the pitch of the pro )eller blades, after the manner illustrated in higs. 1 and 2:

The handle 74 is rotatably mounted upon the instrument board 67 or other fixed part of the aeroplane, but in the instance illus trated it is rotatably mounted concentrically wit the gear 7 6 being shown as supported upon a hub extension 77 of said gear. It

carries a gear 7 8 which meshes with a gear 79 rotatably mounted upon the instrument board as by means of a supporting shaft 80. The gear 79 is shown as being connected with a pinion 81 which meshes with the gear 76, and the shaft is provided with a suitable anti-friction device as 82 to frictionally hold it, and consequently the handle 74:, in any position to which said handle maybe rotated.

The pinion 81 operates the gear 76 for in turn operating the shaft 7 5 either to rotate said shaft or to slide said shaft longitudinal- 1y, as above indicated.

A stationary dial as 83 may be present for indicating the position of the propeller blades in substantially the same manner as described with reference to the dial 65. A pointer 84 may be conveniently connected with the gear 79 to co-operate with the dial 8 3 in the present instance.

The gear 76 is shown for convenience as being of segmental form and from one side thereof projects an arm 85 carrying a stop pin 86 at its outer end projecting into and movable along an arcuate slot 87 which is provided in the instrument board 67. The pin 86 projects at right angles from the arm 85 into the slot- 87. It is slidably mounted within a guide-way 88 provided to receive it at the outer end of the arm and is yieldably urged into the slot as by a leaf spring 89 which is fixed to the arm as at 90 by one of its ends and which has its opposite end engaging within a suitable notch as 91 of the The-pin 86 is thus always normally held within the slot so that the possible movement of the gear 76 about its rotary axis is posi tively limited in both directions by engagement of the pin with the

end walls

92 and 93 of the slot. 7

It will be seen that unless other means than as thus far described be provided, the operator, by movement of the handle 7 4., would be unable to rotate the gear 7 6 beyond the limits defined by the

walls

92 and 93, and it is here pointed out that this amount of move ment is intended to be that amount which is within what may be termed safety limits. The operator may readily adjust his propeller blades to any desired angle as may appeal to him within these limits but if he wishes to adjust the blades into any greater or difier- 1 ent angular position than is permitted within these limits he must necessarily perform a further and definite operation, as will now be referred to. v

Carried upon the handle 74 is a lifter 94 slidably mounted within a transverse bore 95 at the end of said arm 74 and connected with the finger grip 96 of said arm. A spring as 97 is shown for-urging this lifter, and hence the finger grip, always inwardly toward the instrument board 67, but the operator may at any time, by drawing outwardly upon the finger grip, move the lifter outwardly away from the instrument board.

The lifter has a laterally projecting nose 98 at its inner end which is adapted to ride freely through a notch 99 of the stop pin 86 whenever the handle is swung past said pin in either direction.

By this arrangement it will be seen that when the handle 74.- is in position overlying the arm 85, then, and then only, the operator, by drawing out upon the finger grip 96, may lift the stop pin 86 sufliciently far so as to pass over the end wall 92 of the slot 87.

It will be noted that although the handle may traverse the arm repeatedly while the arm is in different positions yet the gear connections between the handle and the arm are intended to be such that the handle will overlie the arm, and the nose 98 will engage within the notch 99, always at the proper time to enable the stop pin to be lifted over the end wall 92 as both the handle and the arm move in a contra-clockwise direction (Fig. 7), the stop pin being dropped again by the nose 98 beyondsaid wall 92 as the handle continues to rotate away from the arm.

Spacedbeyond the wall 92 a second wall 100 is provided-in the path of movement of the stop pin adapted to define a maximum limit to which said pin may move under any circumstances.

Referring to the illustration Fig. 9, it may be correctly stated that the two

opposite walls

93 and 100 are the opposite end walls of a single slot and define the extreme limits of movement of the stop pin, and that the wall 92 constitutes in effect a shoulder intermediate said end walls for confining the movements of the stop pin within restricted limits under normal conditions. 4

It is noted that the wall or shoulder 92 is of less height than the

walls

93 and 100. The stop pin may be lifted over the wall or shoulder 92 but it may not be lifted over either

ofthe walls

93 or 100.

While the position of the arm may in practice be at any desired point for a given angular thrust position of the propeller blades, yet preferably it is intended that when said arm is in position adjacent to but spaced from the shoulder 92 then the propeller blades stand at what may be termed a normal running angle. If the'operator desires his blades to stand in more nearly a feathering position, that is a osition of ess angle, he operates the handle 4 to move the arm into a position nearer to the shoulder 92, a position against said shoulder being the limit to which he can-move without. racing his engine. If the operator, on the other hand, desires his blades to stand in a position of relatively greater angle, as for instance he will probably desire to do after the aeroplane has reached a rarefied atmosphere, he operatesthe handle 74 in an opposite, or clockwise, direction Fig. 7, to move the arm in a direction away from the shoulder 92 more or less according to the dictates of his will.

Movement of the arm 85 in a contra-clockwise direction over the shoulder 92 first brings the propeller blades into a feathering position and continued movement brings them into an opposite angular position thereby applying a brake, or reverse wind pressure, to retard movement of the aeroplane more or less according to the greatness of the reverse angle and speed of the engine, the maximum reverse angle being of course when the stop pin engages the wall 100.

This provision for applying a reverse wind pressure or brake against movement of the aeroplane may be useful at different times but isparticularly so just when and following the time when the aeroplane touches the groundin landing. A skillful manipulation of the propeller blades at this time may bring the aeroplane to a perfect and quick stop.

It is a purpose of this invention to prevent movement of the propeller blades into, or too near to, a feathering position except when the propeller is being driven at a rela tively reduced speed. To this end the drawings herewith, see Figs. 7 to 9, suggest that the engine throttle rod as 101 may be provided with an extension 102-projecting into such relation with the arm 85 as to prevent movement of said arm in acontra-clockwise direction beyond the shoulder 92 except when the throttle is in a slow position. I The throttle extension 102 is shown as an armate plate mounted slidably within an arcuate slot 103 formed through the instrumentboard 67 and having a surface 104 at its outer end arranged to be engaged by a finger 105 which projects radially from the arm 85 in such relation that said arm 85 can not be moved beyond the wall 92 unless the throttle extension or plate 102 be first withdrawn out of the path of movement of the finger.

By this arrangement the operator is required to move his throttle into slow position thereby slowing down the rotation of the propeller, before he is able to move the propeller blades beyond the angular position defined by the stop 92.

It is ar-further purpose of this invention to automatically insure a reduction of the engine speed if for any reason the operator should attempt to. adjust the propeller blades into a feathering or reverse position without having previously manually reduced the en gine speed, and to this end the drawings herewith suggest that the surface 104 which is provided upon the throttle extension for engagement by the finger 2105 of the arm shall be shaped and disposed to constitute a cam with respect to the movement of the finger 105 so that pressure of said finger against said surface will cam, or push, the throttle into slow position as the stop pin 86 moves over and beyond the shoulder 92. In this manner the manual efi'ort of the operator, exertedupon the handle 74, to adjust his propeller blades into a feathering or reversed position will be effective to move the propeller blade as intended, but it will at the same time automatically effect a reduction'in the speed of the engine.

It is a further purpose of this invention to insure against the likelihood of too great an engine speed when the propeller blades are in a reversed angular position, and to this end the drawings suggest that the throttle extension or plate 102 shall provide an end edge sur'- face 106, continuing in a contra-clockwise direction, Fig. surface 106 being adapted to stand beneath the finger 105 whenever the propeller blades arein a reversed position and being co-operative with said finger 105 to normally prevent movement of the throttle sufliciently far to produce a high speed condition of the engine. Note that in. the development illustrated in Fig. 9-the path of travel of the finger 105, as indicated by the dot and dash line 107, is relatively above the surface 106 so that it would be impossible to move the throttle rod into the position in which it is shown if the finger 105 were moved over to overlie the surface 106.

By this means, whenever the operator has moved his propeller blades into a reversed position he will find that any effort which hemay make to speed up his engine beyond a predetermined degree will be definitely opposed by engagement of the surface 106 against the finger 105, a

The relation of the surface 106 to the finger 105 is such that it will permit of a sufiicient speed of the engine so as to enable an operator, if his engine be dead, to start the engine, but it will not normally permit of any considerable speed except when, or until, the finger has been moved clockwise beyond the shoulder 92, and the propeller blades thereby brought into a proper thrust applying pos1- tion for normal flymg.

It may be here noted however that the throttle fed as illustrated includes. a resilient,

or compressible, element 108, between its handle 10!) and the working endor extension plate 102, whereby if desired the Operator 7, from the cam surface 104:, said may be able to operate the handle 109 into a high speed position without a corresponding movement of the surface 106. Thus, as inan emergency, the operator may speed up his propeller to maximum at any time even though the blades be in -reversed position.

The compressible element 108 may take any desired form, but as herein illustrated it consists in a simple cylindrical casing 110 having a plunger 111 movable therein against the compression of a coil spring 112, the easing being connected with the portion 101 of the throttle rod and the plunger being con nected with the extension part or plate 102. It is a further purpose of this invention to provide means for automatically limiting the speed at which the engine may normally be run in proportion to the angular position of r the propellerblades, particularly when said blades are in a reversed position. To this end the drawing, Fig. 9, suggests that the surface 106, instead of being a straight line parallel with the line 107, shall be. curved with respect to said line 107, being relatively further from said line at a pointadjacent the end wall and approaching relatively nearer to said line, and then again curving away from said linetoward the opposite end of said surface. By this arrangement it will be seen that the distance to which the surface 106, and hence the throttle, may be moved toward high speed position will be limited at different stages dependent upon the position of the finger 105. If the finger be at a point substantially mid-way between the shoulder 92 and the wall 100 the throttle may be moved to a fairly high speed position, but if the finger 105 be moved toward the shoulder 92 or toward. the wall 100 the speed of the engine will be necessary less in proportion to the distance of movement of the finger toward said'shoulder or wall as the case may be.

Obviously the surface 106 may be curved or s? aped to any appropriate contour as may be best calculated to produce a proper speed limit position of the propeller blades, and obviously also it may be extended so as to underlie and co-operate with the finger 105 when the blades are in a forward, or non-reversed, positionif desired.

It is a further purpose of this invention to provide means automatically operable to adjust the angular position of the propeller blades in accordance with the altitude of the 1' for the engine incident to any given angular V sure is increased or diminished. As the vehiof the pinion 81 and produce rotation of.

said pinion to a greater or less extent ac cording to the amount to which the rod 115 is lifted. The segment 116 stands normally out of engagement with the pinion 81 so as not to interfere with the manual adjustment of the propeller blades at any time while the vehicle is at or near the earths surface. As the vehicle ascends into the rarefied atmosphere however the segment will engage the pinion and continued ascent of the Vehicle will automatically cause the. segment to move the arm 85 toward the wall 93 and thereby increase the angular thrust of the propeller blades in amount dependent upon the altitude of the vehicle.

. It is noteworthy that the mechanism described for automatically changing the pitch of the propeller blades as the vehicle ascends above the earth is of a flexible or elastic character such that it will, in an emergency,

permit of easy manual adjustment of the blades, by means of the handle 74, into any desired position at any time.

A suitable-dial as 119 is preferably provided concentric with the axial pivot of the arm 85, and co-operat-ive with the finger 105, to' graphically show to the operator the position of the propeller blades at all times.

The dial 83 heretofore described co-operates with the dial 119 as a Vernier device, the dial 119 giving a relatively coarse indication of the position of the propeller blades, and the dial 83 giving a finer indication of the position of said blades.

As many changes could be made in this construction without departing from the scope of the invention as defined in the fol lowing claims, it is intended that all matter contained in the above description, or shown in the accompanying drawings, shall be interpreted as illustrative only and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is p 1. An adjustable propeller mechanism for vehicles, said mechanism including a plurality of propeller blades arranged to project radially in different directions from the propeller shaft of the vehicle and independently connected with-said shaft to rotate upon axes transverse of said propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective axes for changing the pitch of said blades at the will of the operator, and resilient means connected with said blades operable to hold said blades under tension when sald blades are moved by said operating means.

' 2. An adjustable propeller mechanism for vehicles, said mechanism including a plurality of propeller bladesiarranged to project radially in different directions from the propeller shaft of the vehicle and independently connected with said shaft to rotate'upon axes transverse of said propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective axes for changing the pitch of said blades at the will of the operator, and spring means interengaging between said propeller blades respectively and a part fixed to the propeller shaft so as to be tensioned by rotary movement of the blades.

3. An adjustable propeller mechan sm for vehicles, said mechanism including a plurality of propeller blades arranged to project radially in different directions from the propeller shaft of the vehicle and independently connected with said shaft to rotate upon axes transverse of said propeller shaft. op-' erating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective axes for changing the pitch of said blades at the will of the operator, and spring means interengaging oetween said propeller blades respectively and a part fixed to the propeller shaft, said spring means normally holding the blades in one position but being 'yieldable to permit and resist movement of the blades in opposite directions with respect to said normal position.

4; An adjustable propeller mechanism for vehicles, said mechanism including a plurality'of propeller blades arranged to project radially in different directions from the propeller shaft of the vehicle and independently connected with said shaft to rotate upon axes transverse of said propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective axes for changing the pitch of said blades at the will of the operator, a pair of springs. interengaging between said'propeller blades re spectively and a part fixed to the propeller shaft, said pair of springs being operable one to urge the propeller blade in one direction and the other being operable to urge the pro peller blade in an opposite direction, and means to definitely define the normal intermediate position of the blade.

5. An adjustable propeller mechanism for vehicles, said mechan sm including a plurality of propeller blades arranged to project radially in different directions from the propeller shaft of the vehicle, a plurality of stud shafts fixed to the propeller shaft radiating therefrom one for the attachment of each blade, said blades and said stud shafts having parts co-operative by which the blades are rotatably mounted upon said stud shafts upon axes transverse of the propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective stud shafts for changing the pitch of said blades at the will of the operator, and spring means interengaging between said blades and said stud shafts normally holding said blades in a given position of adjustment but yieldable to permit forced movement of said blades in both rotary directions with respect to the normal position of said blades.

6. An adjustable propeller mechanism for vehicles, said mechanism including a plurality of propeller blades arranged to project radially in different directions from the pro peller shaft of the vehicle, a plurality of stud shafts fixed to the propeller shaft radiatin therefrom one for the attachment of eac 1 blade, said blades and said studs having parts co-operative by which the blades are rotatably mounted upon said stud shafts upon axes transverse of the propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in spective stud shafts for changing the pitch of said blades at the will of the operator, a pair of coil springs mounted upon each stud shaft each spring having one end connected the two with the adjacent propeller blade, springs upon .each stud shaft being wound in opposite directions away from the point of connection with the blade and having their opposite ends fixed to the stud shaft'so that said springs thereby exert a tendency to move the blade in oppos tion to each other about the respective stud shaft, and means carried by the respective stud shafts and engaging said springs to determine the normal POSI- tion of the blades while permitting forced movement of the blades and consequent tensioning of the springs by operation of said operating means.

7. In combination, an engine having a drive shaft and a propeller connected with said drive shaft 'to be rotated by the engine, means by which the propeller blades are pivotally mounted for adjustment into different angular positions upon axes transverse to the length of the shaft, and actuating means for adjusting said blades including a rod extending through said engine concentric with the axis of rotation of the engine shaft and continuing beyond theend of said shaft and having a part lapping back. about the outer surface of said shaft into engagement with said blades.= a

.8. The combination with a propeller having adjustable blades, ofcontrol mechanism for unison upon their resaid blades including parts manually operable' to move the blades beyond safe limits, and means to define the safe limits and prevent unintentional movement of the blades beyond said limits.

9. An adjustable propeller mechanism for vehicles, said mechanism including a plurality of propeller blades arranged to project radially in. different directions from the propeller shaft of the vehicle, a plurality of stud shafts fixed to the propeller shaft radiating therefrom one for the attachment of each blade said blades and said stud shafts having parts co-operative by which the blades are rotatably mounted upon said stud shafts upon axes transverse of the propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective stud shafts for changing the pitch of said blades at the will of the operator, spring means interengaging between said blades and said stud shafts normally holding said blades in a given position of adjustment but yieldable to permit forced movement of said blades in both rotary directions with respect to the normal position of said blades, and means to definitely define the normal position of the blades.

10. An adjustable propeller mechanism for vehicles, said mechanism including a plurality of propeller blades arranged to project radially in different directions from the propeller shaft of the vehicle, a plurality of stud shafts fixed to the propeller shaft radiating therefrom one for the attachment of each blade, said blades and said stud shafts having parts co-operative by which the blades are rotatably mounted upon said stud shafts upon axes transverse of the propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective stud shafts for changing of said blades at the will of the operator, spring means interengaging between said blades and said stud shafts normally holding said blades in a given position of adjustment but yieldable to permit forced movement of said blades in both rotary directions with respect to the normal position of said blades, and means carried by each stud shaft co-operative with said spring means to definitely define the normal position of the blades.

11. An adjustable propeller mechanism for vehicles. said mechanism including a plurality of propeller blades arranged to project radially indifferent directions from the propeller shaft of the vehicle, a plurality of stud shafts fixed to the propeller shaft radiating therefrom one for the attachment of the pitch each blade, said blades and said stud shafts to another portion of the vehicle by which to upon axes transverse of the propeller shaft, operating means extending from said blades rotate said blades in unison u on their respective stud shafts of said blades at the will of the operator, spring means interengaging between said blades and said stud shafts normally holding position of adjustment said blades in a given but yieldable to permit forced movement of said blades in both rotary directions with respect to the normal position of said-blades, and means carried by each stud shaft projecting therefrom into engagement with said spring means to definitely define the normal position of the blades.

12. An adjustable propeller mechanism for vehicles, said mechanism including a plurality of propeller blades arranged to project radially in different directions from the propeller shaft of the vehicle, a plurality of stud shafts fixed to the propeller shaft radiating therefrom one for the attachment of each blade, said blades and said stud shafts having parts co-operative by which the blades are rotatably mounted upon said stud shafts upon axes transverse of the propeller shaft, operating means extending from said blades to another portion of the vehicle by which to rotate said blades in unison upon their respective stud shafts for changing the pitch of said blades at the will of the operator, sprin means interengaging between said blades an said stud shafts normally holding said blades in a given position of adjustment but yieldableto permit forced movement of said blades in both rotary directions with respect to the normal position of said blades, and means fixed rigidly upon each stud shaft and having co-operative engagement with said spring means to definitely define the normal position of the blades.

13. The combination with a propeller having adjustable blades, of control mechanism for said blades including parts manually 0perable to adjustably move the blades, means to normally restrict the movement of said blades within given limits, and means manually operable to effect a movement of the blades beyond said limits at the will of the operator.

14. The combination with a propeller having adjustable blades, of control mechanism for said blades including parts manually operable toadjustably move the blades, means to normally restrict the movement of said blades within given limits, means manually operable to effect a movement of the blades beyond said limits at the will of the operator, and means to-insure a slow speed condition of the propeller when the blades are adjusted beyond said given limit.

15. The combination with a propeller having adjustable blades, of control mechanism for said blades including parts manually opfor changing the pitch the erable to adjustably move the blades, means to normally restrict the movement of said blades within given limits, means manually operable to effect a movement of the blades beyond said limits at the will ,of the operator, and means effective to produce a slow speed condition of the propeller incident to move ment of the blades beyond said given limits.

16. The combination with a propeller having adjustable blades and drive means for said propeller, of control mechanism for said blades including parts manually operable to adjustably move the blades, means to normally restrict the movement of said blades within given limits, means manually operable to efiect a movement of the blades beyond said limits at the will of the operator, and means to insure a slow speed condition of propeller when the blades are adjusted beyond said given limits, together with means manuallly operable in an emergency to increase t e speed of the propeller when the blades are adjusted beyond said given limits.

17 The combination with a propeller havingadjustable blades and drive means for said propeller, of control mechanism for said blades including parts manually operable to adjustably move the blades into various for- Ward and reverse angular positions, and means to control the speed of the propeller in accordance with the angular position of the blades.

, 18. The'combination with a propeller having adjustable blades and drive means for 100 said propeller, of control mechanism for said blades including parts manually operable to adjustably move the blades into various forward and reverse angular positions, and means to insure a slow speed condition of the 105 propeller when the propeller is in a reverse angular position.

19. The combination with a propeller having adjust-able blades, of control mechanism for said blades including a longitudinally 110 movable control rod, manually operable means to slide said rod for adjustably moving the blades into various angular positions, and means automatically operable to slide said rod for adjusting the blades dependent 1 5 upon the altitude of the mechanism.

20. The combination with a propeller having adjustable blades, of control mechanism for said blades including parts manually operable to adjustably move the blades into v'a- 120 rious angular positions, and means normally disconnected from the blades but automaticalature.

ING.