US3302725A

US3302725A - Variable pitch marine propeller

Info

Publication number: US3302725A
Application number: US513611A
Authority: US
Inventors: Peter F Brimble; Joseph F Scheidbach
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-10-22
Filing date: 1965-10-22
Publication date: 1967-02-07
Anticipated expiration: 1984-02-07

Description

Feb 7, 95? in. F. BFM/AELE ETAL' 3,30%??5 VARIABLE FITCH MARINE PROPELLER Original Filed Aug. 3, 1961 2 Sheets-Sheet l Feb '39 w67 P. @Rw/@LE HAL 1302??25 VARIABLE FITCH MARINE ROPELLER Original Filed Aug. 3, 1961 2 Sheets-Sheet 2 United States Patent Office 3,362,725 Patented Feb. 7, 1967 3,302,725 VARIABLE PITCH MARINE PROPELLER Peter F. Brimble and Joseph F. Scheidbach, Los Angeles. Calif., assignors to Stuart A. Krieger, Norman J. Allin, Bradley Kendis, Alvin S. Isaacson, and Stanley L. Gendler, doing business as Westwood Associates, Los Angeles, Calif.

Continuation of application Ser. No. 385,086, July 24, 1964, which is a continuation of application Ser. No. 129,147, Aug. 3, 1961. This application Oct. 22, 1965, Ser. No. 513,611

15 Claims. (Cl. 170-160.13)

This application constitutes a continuation of our application Ser. No. 385,086, tiled July 24, 1964, for 'a Variable Pitch Marine Propeller, which, in turn, is a continuation of our application Ser. No. 129,147, tiled Aug. 3, 1961, for a Variable Pitch Marine Propeller, now abandoned.

The present invention relates to propellers and more particularly to marine propellers and means for varying the pitch thereof.

When a -boat is propelled by means of a propeller immersed in Water and driven by a motor, it is very desirable to obtain maximum eiciency and/or maximum speed. In order to accomplish such an objective it is necessary among other things, for the motor to run `at an optimum revolutions per minute and for the propeller to have a pitch that will permit the engine to operate at the desired speed and also provide an eicient drive in the water. The foregoing are inturn dependent upon the operating characteristics of the boat i.e., the load in the boat, the speed of the boat, the condition of the seas etc. Since such -factors constantly vary, it is necessary to endeavor to reach a compromise combination of motor and propeller that will produce acceptable performance over a wide range `of operating conditions.

In small light weight pleasure boats that are subjected to a wide range of operating conditionsit has been very difficult if not impossible to reach a compromise that is satisfactory. In a light weight planing type of runabout driven by an outboard motor, the weight of the load inside of the boat frequently varies over a very wide range and the boat may be employed for towing one or more water skiers. As a result, the requirements for propelling the boat vary over such an extremely wide range that one propeller will not provide proper operation. More particularly, when initially starting out in a heavily loaded boat. the boat travels through the water very slowly and requires a large amount of thrust. As a result during such periods it is highly desirable to employ a propeller having a small pitch. Such a propeller will permit the motor to run at a high sneed and develop large amounts of power as well as permit the propeller to operate efficiently in the water. This will permit the boat to rapidly accelerate to a speed that will cause the boat to plane on the surface of the water. This is particularly true where the boat is towing a skier. Once the boat has acquired a planing attitude, if a low pitch propeller is employed the motor must =be run at maximum speed and yet the boat and any skiers therebehind will be traveling at less than the maximum speed obtainable with a higher pitch propeller.

In the event the higher pitch propeller is employed when the boat is initially starting out and traveling slow, the propeller will be very inetiicient. In addition, the speed of the motor will be held down to such a low amount the motor will not develop maximum power. This in turn results in very poor acceleration that makes it very diicult if not actually impossible for the boat and any skiers therebehind to rise up onto the surface of the water and plane thereacross.

In order to overcome such `difficulties numerous attempts have been made to provide a variable pitch propeller wherein the pitch of the blades may be set to the optimum amount for the particular operating conditions. In one form of variable pitch propellers, such as disclosed in U.S. Patent No. 2,953,208 entitled Variable Pitch Marine Propeller and led in the name of Charles A. OConner, the` propeller must be stopped and removed from the Water while extensive adjustments are manually made thereto. As a result to vary the pitch of the pro- -peller it is not only Idifficult and inconvenient to do so but in addition such propellers are not well suited for use wherein drastic changes occur in the propeller requirements during operation of the boat. More particularly, if a low pitch is required to cause the boat and any skiers therebehind to attain a planing speed and a higher pitch is desirable for maintaining the required planing attitude, the pitch of such a propeller can not be increased without causing the boat and skier to stop.

In another form of variable pitch propellers means are provided whereby the pitch of the propeller maybe altered while the motor is running. However, heretofore such means have been extremely complex and cumbersome and as a result they have not only been expensive and diiiicult to operate but have also required frequent servicing and have been subject to frequent mechanical dificulties. As a result such propellers have found very limited use on pleasure craft.

It is now proposed to provide a variable pitch propeller that overcomes the foregoing difficulties. More particularly, it is proposed to provide a reliable and inexpensive propeller wherein the pitch of the blades thereon may be varied while the motor is runnin, According to one form of the invention the propeller employs a plurality of blades that are pivotally mounted on two separate mounting portions of a hub means so that the relative positions of the two portions will be effective to determine the pitch of the blades. One of the mounting portions may be operatively connected to the drive shaft by means of a lost motion connection whereby during normal operation of the motor, the propeller and the blades thereon will be driven in a normal manner. The other mounting portion may be operatively interconnected with the drive shaft by a drive means that will cause the two portions to change their relative positions as a result of the propeller tending to overrun the drive shaft. Thus whenever it is desired to change the pitch of the blades, the speed of the motor may be momentarily reduced abruptly enough to produce an overrunning tendency of the propeller and then the speed of the motor may be again increased. As a result during this interval the two mounting portions will change their relative positions and therefore the pitch of the blades. As a `consequence the motor will resume driving the propeller but with a new pitch. Since the interval of time required for the foregoing operation to occur is very short the pitch may be changed without producing a perceptible slowing down of the boat. lt may thus be seen that in the event the operating conditions of a boat change suiciently during the operation thereof to justify the changing of the pitch of the propeller, the pitch may be changed while the boat is running without materially interfering with the `operation of the boat -by merely decreasing the speed of the motor for a verv short interval.

These and other features and advantages of the present invention will become readily apparent from the following detailed description of one form of the present invention, particularly when taken in connection with the accompanying drawings wherein like numerals refer to like parts and wherein:

FIGURE 1 is an end view of a propeller embodying one form of the present invention;

FIGURE 2 is a side View of the propeller of FIG- URE 1;

FIGURE 3 is a transverse cross section view, on an enlarged scale, taken substantially along the plane of line 3 3 in FIGURE l;

FIGURE 4 is an exploded perspective view of the propeller of FIGURE 1;

FIGURE 5 is a fragmentary view of the propeller of FIGURE 1;

FIGURE 6 is a perspective view of one of the elements in the propeller; and

FIGURE 7 is a side view of a boat and skier being propelled by a motor equipped with the propeller of FIG- URE l.

Referring to the drawings in more detail, the present invention is embodied in a propeller 10 adapted for propelling a light weight planing boat 12 across the surface of the water. Although the boat 12 may be of any desired variety, in the present instance it employs an outboard motor 14 that `is mounted on the yboat transom. The motor 14 may be remotely controlled from the front of the boat 12 by means of a set of manual controls that includes a suitable throttle lever 16 and an ignition switch 18. The ignition switch 18 may be effective to open the ignition system or short it to ground to thereby prevent the cylinders in the motor firing. If desired, one or more water skiers 20 may be towed behind the boat 12 by means of a rope 22 secured to the motor or transom.

In a light weight planing boat 12 of the present variety the operating characteristics thereof as well as the requirements of the motor 14 and the propeller 10 will vary over a considerable range depending upon how heavy a load is disposed inside the boat 12, whether the boat 12 is traveling through the water at a slow rate or is planing on top thereof at a high rate of speed and last but by no means least whether or not one or more skiers 20 is being towed behind the boat 12 and whether or not the skier is planing on the surface of the water. Heretofore in such a boat and motor combination it has been customary to utilize a high power motor together with a propeller that was a compromise giving reasonable performance during the various operating conditions.

In the present instance the propeller 10 has a pitch which may be adjusted over a wide range to satisfy the requirements during various operating conditions. Although the propeller 10 may have a diameter and number of blades suitable for the particular motor and boat with which it is to be employed, in the present instance for purposes of illustration, the propeller 10 has three

blades

24, 26 and 28. The

blades

24, 26 and 28 are mounted on a hub 30 at circumferentially equally spaced intervals therearound so as to project radially outwardly therefrom so as to react with the water as the propeller 10 rotates therein. The hub 30 may be secured to the propeller or drive shaft 32 of the motor 14 for normally rotating in a clockwise direction (as seen in FIGURE 1) and producing a thrust that will tend to drive the propeller 10 forwardly (to the left as seen in FIGURES 2 and 3).

The hub 30 may `be connected to the drive shaft 32 by any suitable means. In the present instance a pair of

sleeves

34 and 36 are provided that are concentric with each other. The inner sleeve 34 includes a cylindrical passage that is adapted to receive the drive shaft 32. This sleeve may be secured to the drive shaft by means of a shear pin 38 that extends through registering -openings lin the drive shaft 32 and the sleeve 34. The shear pin 38 preferably has a limited strength that is adequate to transmit normal operating torque from the shaft 32 to the sleeve 34 but is inadequate to transmit a large torque such as would occur when one of the

blades

24, 26 or 28 strikes an obstruction.

The outer sleeve 36 lits over the exterior of the inner sleeve 34 and is connected thereto by means of a slipping clutch. The present clutch comprises a rubber bushing 40 that is compressed between the two sleeves. The rubber bushing 40 is effective to provide a friction drive that will transmit normal operating torque. However, the rubber bushing 40 will be effective to limit the torque that may be transmitted to the

propeller blades

24, 26 and 28 and thereby provide additional protection against damage to the

blades

24, 26 and 28 in a manner similar to the shear pin 38.

The exterior of the sleeve 36 includes a first portion 42 of reduced diameter and a second portion 44 of greater diameter that is separated from the first portion by a radial shoulder 46. Each of these portions 42 and 44 form substantially cylindrical surfaces that are concentric with the axis of the shaft 32. The forward end of the sleeve 36 may include a plurality of

arms

48, 50 and 52 that project radially outwardly therefrom. In the present instance there are three arms, each of which has a square cross section with a plane forward face 54 and a reverse face 56.

In addition a pair of retaining rings 58 and 60 may be provided on the exterior of the sleeve 36. The first ring 58 includes a cylindrical passage that forms a snug fit on the enlarged portion 44 of the sleeve 36 so as to permit the ring 58 to rotate thereon. The front end of the ring 58 includes an annular recess 62 that extends therearound substantially concentric with the axis of the shaft 32. The depth and width of this recess 62 are just large enough to permit the

arms

48, 50 and 52 to be disposed therein. The radially outer ends of the

arms

4S, 50 and 52 terminate adjacent the outside 61 of the recess 62 while the front side of the arms is substantially flush with the front surface of the ring 58. The bottom 64 of the recess 62 forms a radial face that slides against the rear side of the arms so as to limit the axial movement of the ring 58.

A plurality of

arcuate blocks

66, 68 and 70 may be disposed in the recess 62 adjacent the outside arm 61 thereof. These

blocks

66, 68 and 70 which correspond in number to the number of

arms

48, 50 and 52 are secured against the bottom 64 at circumferentially equally spaced points. The ends of the blocks form forward stops 72 and reverse stops 74. The stops 72 and 74 are separated from each other by circumferentially extending

pockets

76, 78 and 80. Each of the

pockets

76, 78 and 80 is adapted to receive one of the

arms

48, 50 and 52 whereby the arms may move through the pockets. At one extreme of movement the forward faces 54 will engage the forward stops 72 while at the other extreme the reverse faces 56 will engage the reverse stops 74. It may thus be seen that the engagement of the

arms

48, 50 and 52 and the

blocks

66, 68 and 70 will thereby limit the amount of relative rotary movement between the

sleeves

34 and 36 and the retaining ring 58 as well as permit torque to be transmitted between the sleeves and ring 58.

The second retaining ring 60 includes a passage 82 that extends axially therethrough for receiving the sleeve 36. The passage 82 includes a first cylindrical section 84 that forms a snug fit on the exterior of the enlarged portion 44 suitable for permitting the ring 60 to rotate upon the exterior of the sleeve 36. A second section 86 of the passage 82 has a smaller diameter and is separated from the first section 82 by means of a radial shoulder 88. This shoulder 88 engages the shoulder 46 and thereby limits the forward axial movement of the ring 60. The inside diameter of the second section 86 is preferably larger than the diameter of the small portion 42 of the sleeve 36 so as to provide an annular clearance 89 space therebetween.

A plurality of bolts 90 may extend through the

blocks

66, 68 and 70 and first ring 58 and on into the second ring 60. These bolts 90 will thus not only secure the blocks 66, `6 8 and 70 in position in the recess 62 but will also interconnect the

rings

58 and 60 with each other and compress the faces 92 and 94 of rings together. The mating faces-92 and 94 on the

rings

58 and 60 may be provided with a plurality -of recesses that are'circumferentially spaced therearound and correspond in number to the number of

blades

24, 26 and 28, three in the present instance. The recesses in the two faces 92 and 94 are positioned to register with a complementary recess in the other face to thereby form a plurality of pockets. Each pocket includes a cylindrical entrance passage 96 with an enlarged annular chamber 98 at the radially inner end thereof. This chamber 98 is separated from the pasj sage 96 by means of a radial shoulder 100. Each of the

blades

24, 26 and 28 includes a pivot shaft 102 on the inner end thereof that fits into the pockets. Each shaft 102 includes a cylindrical portion 104 that -fits the passage 96 and an enlarged head 106 that lits intothe chamber 98 whereby the head will bear against the shoulder 100.

It may thus be seen thatif the shafts 102 are placed in the recesses on one face 92 or 94 and then the two retainer rings 58 and 60 are secured together, the shafts 102 Awill be locked in the pockets so-as to secure the

blades

24, 26 and 28 in position. Since the shafts 102 and the pockets havecircular cross sections, the shafts 102 can rotate in the pockets.4 Thus although the

blades

24, 26 and, 28 are secured inposition on the hub they may be rotated so as to'vary the pitchthereof.

In order to fix the pitch of the blades V24, 26 and 28, a control ring 110may be provided. The present control ring 110includes a passagetthat extends axially therethrough and is adapted to rotatably fit into the reduced portion 42 of the sleeve 36. The front of the control ring 110 includes 'a radial surface 112 that slideably engages the rear surface of the retainer rin'g 60 and a projection 114 that extends forwardly therefrom into the clearance space 89 formed inside of the retainer ring 60. A set screw 116 may be providedthat extends `radially inwardly through the retainer ring 60fto bear against the outside of theprojection 114. Byvadjusting the force the screw 116 exerts ongthe projection it will bepossible to preset theamount-of friction opposing movement between the retaining rings 58 and 60 and the control ring 110. It has been found that by providing -a small Vclearance space 118 between the'exteriorof the sleeve 36 and the interior Yof theprojection 114 the force of the screw 116 will tend ,to:,deflect' theprojection 114 and thereby permit a more accurate setting of the frictional drag. v i

The exterior of control-ring 110 includes a groove 120 thatextends radially inwardly into the control ring 110. The present groove 120 is substantially rectangular `in cross section and extends continuously around the contro'l ring to form atleast one cam surface. The cam surface undulates in an axial direction of theV control ring as it extends circumferentially around the ring 110. In the present instance th'e pattern of the cam surface repeats itself three times: or the same number as the blades 24,

26and28.

Each of the

blades

24,26 and 28 includes a pin 122 that extends intotheYgroove 120 so as to engage the cam surface and be positioned thereby.' Since the cam surface undulates in an-axial -direction the axial positions ofthe pins 122VV will be determined by the angular positions of the control ring 110. Since the groove 120 repeats itself for each

blade

24, 26 and28, all of the

blades

24, 26 and 28 will have4 the same pitch. More particularly, if the pins 122 are `located at an apex 124 that is disposed at `a maximum rearward direction, the blades will have a maximum pitch. vIf the pins 122 are at an apex 126 havingl a minimum rearward direction, the bladeswill have a minimum pitch. If the pins 122 are disposed in an intermediate portion 128 of the cam surface, the

blades

24, 26 and 28 will have some intermediate pitch.

-In order to rotate the control ring 110 about the sleeve 36, a one way drive 128A may be provided. This one way drive 128A will be effective to cause the ring 110 to be free to rotate in one direction about the shaft 32 while at the same time preventing the ring rotating in the reverse direction. In the present instance the one way drive 128A comprises a so-called `ratchet that includes complementary teeth 132 and 134 on the rear of the control ring 110 Vand the front of a drive ring 130. The drive ring includes a passage 136 that fits onto the exterior of theshaft 32. A detent 138 may be provided on the inside` of the drive ring A130 so as to extend into a slot 140 or key way in the end of the sleeve 36. The detent 138 will thus prevent the ring 130 rotating on the sleeve 36 while at the same time permitting the ring 130 to move axially thereon. v A spring 142 may bear against the end of the drive ring 130 so as to resiliently bias the teeth 134 on the ring 130 against the; teeth. 132 on the other control ring 110. The opposite end-of the spring 142 may bear against a spinner nut 144. The spinner nut 144 is threaded onto the-.end of the drive shaft 32 so as to secure the entire assembly thereto. It may thus be seen that when the control ring 110 tends to rotate in one direction relative to the drive ring 130 the teeth 132 and 134 will mesh and thereby prevent the

rings

110 and 130 from rotating. However, if the control ring 110 rotates in the reverse direction the teeth will slide up on each other and force the ring 130 axially against the spring 142 until the teeth have moved relative to each other by an amount corresponding to the pitch of the teeth. At this point the next succeeding teeth will engage.

AIn order to employ the present invention, the propeller 10 may be first assembled in the following manner. Theprojection 114 on the forward endA of Ythezcontrol ring 110 may irst be inserted into the interior of the retainer ring 60 and the set screw 116 tightened enough to secure the two

rings

60 and 110 together.

shafts 102 in the recesses in the face94 andthe pins 122 in the groove 120. The retaining ring 58 is then put in position and the blocks 66,- 68 and 70 bolted thereto. This will thus form a sub-assembly having the

blades

24, 26 and 28 mounted thereon.v l. v l i The

sleeves

34 and 36 may now be placed concentrically on the shaft 32 and attached thereto by means of the shear pin 38. Next the Vsub-assembly may be positioned thereon so that the

arms

48, 50 and 52 are, disposed in the

pockets

76, 78 and 80 and bear against the bottom 64. Following this the drive ring 130 and spring,142 may be placed on the end of the sleeve 36,and the spinner nut 144 tightened soas to compress alll of the

rings

58,60, 110 and 130 forwardly toward the arms 48, 5 0 and 52 to thereby secure the entirepropeller 10 in position on the vshaft 32.-

After the propeller 10 has been assembled on the drive shaft 32, it may be placed in the water and the motor 14 started. If the motor 14 is in forward gear the drive shaft 32 will rotate and carry the two

sleeves

34 and 36 therewith. If the shaft 32 is rotating in the forward direction the

arms

48, 50 `and 52 will rotate inside of the recess 62 until the forwardfaces 54 of the

arms

48, 50 and 52 engage the forward stops 72. The two retaining rings 58 and 60 will then move with the

sleeves

34 and 36 and the entire propeller 10 will be driven thereby. The

blades

24, 26 and 28 will then react with the water to produce a thrust for driving the boat 12 and any skiers 20 therebehind across the water. The pitch of the blades ,24, 26 and 28 is preferably set at the correct amount for this type of operation. That is, if the boat 12 is just starting to move and it is not yet planing, the propeller 10 may preferably have a low pitch. This is especially true if there is a water skier 20 at rest in the water and holding onto the end of the rope 22 ready to be towed. The pinsV 122 will thus be located at the apexes 126. By employing a low pitch the propeller will operate more effectively and also will permit the motor to run at a sufciently high rate of speed to develop a large amount of power. This in turn will permit the boat and any skiers therebehind The

blades

24, 26 i and 28 may next be mounted inposition;by placing the to rapidly accelerate to a sufficient speed to cause the boat 12 and any skier 20 to rise up and plane across the surface of the water.

Once the boat and/or skier has been accelerated to a high speed and has attained a planing attitude on the surface of the water, the amount of power required to drive the boat and skiers at a given speed will be greatly decreased. In addition, if the propeller has a low pitch the motor 14 will not be capable of turning over at a sufficiently high speed to cause the boat to travel at top speed. Accordingly once the boat 12 and skier 20 are planing it may be desirable to increase the pitch of the

blades

24, 26 and 28 without in any way slowing the boat 12.

In order to increase the pitch, the operator may merely cause the motor 10 to abruptly slow down for a very short interval. This may be accomplished by quickly moving the throttle lever 16 toward the closed position or actuating the ignition switch 18. However, it has been found advisable to employ a shift control button 146. This button 146 is effective to actuate a time delay circuit which will cause the ignition system to become inactivated for some predetermined interval of time such as one second or less. The instant the motor 14 starts to slow down, the propeller 10 will tend to overrun the propeller shaft 32.

When this overrunning occurs the two retainer rings 58 and 60 and the blades thereon will rotate about the exterior of the sleeve 36. The

arms

48, 50 and 52 will then move through the

pockets

76, 78 and 80 toward the reverse stops 74. Since the 'teeth 132 and 134 are meshed with each other, the teeth 132 will slide across the faces of the teeth 134 and force the drive ring 130 to move axially along the shaft 32 toward the spinner nut 144. The amount of overrunning force, i.e. how abruptly the motor must be slowed down, that is required to produce this motion will be determined by the ramp angle of the teeth 132 and 134 and the force from the spring 142. If the overrunning is of sufficient magnitude, the teeth 132 and 134 will slide relative to each other until they have moved by an amount at least equal to the pitch thereof. When this amount of motion has occured, each of the teeth will have dropped into engagement with the next succeeding teeth and will lock the

rings

110 and 130 together but will be displaced by an amount equal to the pitch of the teeth. This motion will normally occur in a" small fraction of a second and will place the propeller in a cocked position for changing the pitch.

If the motor 14 is again accelerated the

arms

48, 50 and 52 will move forwardly through the

pockets

76, 78 and 80 until the faces 54 again engage the stops 72. At the same time, since the teeth 132 and 134 have been locked in engagement with each other the control ring 110 will be locked to the drive ring 130 which is keyed to the sleeve 36. As a result, as the shaft 32 rotates together with the

sleeves

34 and 36, the frictional connection provided by set screw 116 will allow relative motion to occur between

rings

60 and 110. As the two

rings

60 and 110 move relatively, the pins 122 will move along the groove to thereby vary the pitch of the

blades

24, 26 and 28. The

rings

58 and 60 together with the

blades

24, 26 and 28 will then be driven in the normal manner. The amount of the change of pitch will be determined by the spacing of the teeth 132 and 134 and the slope of the groove 120. This, of course, may be chosen to provide a suitable amount of control for the installation being employed.

It is therefore apparent that the pitch of the

blades

24, 26 and 28 may be varied by merely abruptly slowing the motor 14 for a very short interval. Thus the pitch may be varied while there is no load on the propeller even though the boat 12 is travelling through the water and the motor 14 is running. Since the interruption required in the drive of the motor 14 is very short, there will not be any perceptible change in the speed of the motor.

It may thus be seen that a propeller 10 has been provided that is not only simple and reliable in operation but also will permit the pitch of the

blades

24, 26 and 28 to be varied while the motor 14 is running. Although only one embodiment of the invention has been disclosed, it will be readily apparent to those skilled in the art that numerous changes and modifications may be made thereto without departing from the spirit of the invention. Accordingly the foregoing description and drawings are for illustrative purposes only and are not intended to limit the invention which is defined only by the claims which follow.

What is claimed is:

1. A variable pitch propeller for being mounted on a drive shaft 'and driven thereby, said propeller comprising the combination of:

hub means having a passage extending therethrough for receiving said shaft, said hub means including a first annular member and a second annular mem- -ber concentric-with said passage, said first member Ibeing movable about said shaft between two extreme positions relative to the second member,

drive means connecting the drive shaft to said hub means for driving said hub means in a forward direction and in a reverse direction,

pitch means disposed concentrically Iabout said drive shaft and mounted to rotate about said drive shaft relative to said hub means between-a plurality of stations, p

a cam surface on the pitch means,

a lost motion connection in said drive means connecting the first annular member with said shaft to provide angular movement of the first annular member between said extreme positions relative to the second annular member,

means frictionally interconnecting the first annular member with the pitch means, said friction means being effective to transfer a suliicient amount of torque between the first annular member and the pitch means to move said pitch means and said first annular mem-ber together in a first direction and to provide for relative movement between said first annular member and said pitch means when the torque between the first annular member and the pitch means is greater than said sufficient amount,

a one-way drive interconnecting the said pitch means with said shaft to permit the pitch means to rotate about said shaft in said first direction but to prevent the pitch means rotating yabout said shaft in the opposite direction,

at least one of said annular members having a sufiicient angular moment of inertia to produce a torque xbetween said annular members when said hub means tends to overrun said drive shaft in said first direction and to simultaneously move the first annular member from one of ythe extreme positions to the other extreme position and the pitch means from one station to the next station 'when said hub means overruns said shaft, said one-way drive being effective to retain said pitch means in said next station when said hub means is not overrunningV said shaft, said friction means being effective to provide for the first annular member returning to said other extreme position when said hu-b means is being driven in al forward direction by said shaft, and

at least one blade pivotally mounted on Iat least one of said annular members and having a cam follower that engages said cam surface and positions said vblade with a pitch determined by the relative angular position of said members and said pitch means.

2. A Variable pitch propeller for being mounted on a drive -shaft and rotatably driven by the shaft in a forward direction and a reverse direction, said propeller comprising the combination of:

hub means having a passage extending therethrough,

said hub means including a first portion and a second portion that are concentric with said passage, said second portion being movable relative to the first portion between a first extreme position and a second extreme position.

surface, said blade having a pitch determined by the angular position of the pitch means relative to said portions.

gular positions of that portion and the pitch means. 4. A variable pitch propeller for being mounted on a drive means connecting said first portion to said shaft hub means having a passage extending therethrough to drive said first portion in both of said directions, for receiving said shaft, said hub means including a lost motion connection connecting the second pora first portion and a second portion, the second portion to said shaft, said lost motion connection protion being movable about said shaft relative to the viding for movement of the second portion between first portion and between two extremel positions, the first extreme position and the second extreme drive means on said hub means connecting said hub position, means to said drive shaft for driving said hub means, pitch means disposed on said shaft and interconnected pitch means disposed concentrically about said drive with said second portion to move in a first direction shaft, between a plurality of stations, friction means connecting the second portion With said means continuously frictionally connected to the secpitch means, said friction means being effective to ond portion and the pitch means to provide for insure the second portion and pitch means rotating Imovement of the second portion and the pitch means in unison when the torque between said portions is in the first direction relative to said shaft during less than a predetermined amount, said friction intervals when said propeller is overrunning said means being effective tio provide for relative moveshaft and during intervals when said propeller is ment between the first portion and pitch means when driven in the reverse direction, said torque is greater than said amount, a-ione-way drive connecting the pitch means with said a cam surface on said pitch means,

shaft to provide for the pitch means rotating about at least one blade pivotally mounted on said first porsaid shaft in said first direction and to prevent said tion and having a cam follower engaging said cam pitch means rotating about the shaft in the opposite surface, said cam surface having a profile that will direction, vary the pitch of said blade as a function of therela cam surface on said pitch means, ative angular positions of said first portion and said at least one blade pivotally mounted on at least one pitch means, v

of Sold Portions, and means responsive to the angular inertia of said hub 'a cam follower on said blade and engaging said cam 30 means and having -a mass that is sufficient to move the pitch means and second portion from the first extreme position to the second extreme position when said hub means tends to forwardly overrun said `3. A variable pitch propeller for Ibeing mounted on a drive shaft and rotatably driven by the shaft forwardly, and reversely, said propeller including the combination of:

vhub means including a first portion and a second porshaft to thereby move said cam surface to a new position relative to said follower, and rneans for maintaining the cam surface in the new position, said last means being effective to overcome the torque of said friction means when said shaft is means connecting said first portion to said shaft to drive said first portion,

blade having a pitch determined by the relative andriving said propeller in the forward direction. 5. A variable pitch propeller mountable on a drive shaft to be driven thereby, including the combination of:

hub means having a passage extending therethrough for receiving said shaft, said hub means including at least one portion movable about said shaft between lost motion means connecting the second portion to 45 rst and second extreme positions,

said Shaft, Said IOS IIlOiOn means providing fOr drive means interconnecting said drive shaft with said thesecond portion rotating about said shaft between hub means for driving said hub means in a rst dithe first extreme position and the second extreme rection, Position, .a -lost motion connection in said drive meansintervsand lost motion gncans being effective, t0 retain Said 5o connecting the portion with said shaft to provide second portlon 1n one of the cxtreme positions when for the portion rotating about the shaft through a pre- Sn1d Propeller S being drlYen orWelrdlY, Said lOS -determined arc between the two extreme positions, Inolon rneanS being effeetlVe to PrOVde for Said said lost motion connection being effective to prosecond portlcn moving lnto the other of said cX- vide for the portion remaining in the first of said exrerne PosltlonS durlng Intervals When Said Propeller treme positions when said shaft is driving said hub ,tends to forwardly overrun Said Shaft and during means in the first direction, said hub means'carryln'feIVlS Wl'len Sald Propeller lS drlVen reVerSelY, ing a sufficiently large mass to move the portion to Plien Ineens dSPOSed on Said Shaft and interCOnne-Ced the other of said extreme positions during intervals Wlll Said Second Por'flon to rnOVe in a lrSf direction when said hub means is overrunning said shaft in the when said second portion moves in the first direcfirst direction, t 'oon from tlle first extreme Posltlon t0 'ille SeCOnd pitch means disposed concentrically on said drive shaft eXtreme P0 S1'f10n, and mounted to rotate about said drive shaft, a one-Way drive connecting said pitch means with said at least one propeller blade,

Shaft f o ProVlCle for the Pllell means InOVlng in `the mounting means pivotally securing said blade on the llrSt dlreetlon .Wltll the Second Portion Wllen Said hub means and the pitch means, said blade having a SeeOndPol l10n roe'feS 1n the IS CllreClOn between pitch determined by the relative angular position of said extreme pos1t1ons, sa1d one-way drive being efthe pitch means, fective to retain s ald pitch means in a fixed position means .interconnecting the Pitch means with vin@ por. When Sold Sllll;t 1S drlVlng Said Propeller forwardly tion for moving said pitch lmeans into a new posiand the Second Portlon InoVeS ln lle OPPOSe dreetion each time the portion moves from the firstextion from the second extreme position to the first treme position to the second extreme position, and extreme position, and means for maintaining a change in the" relative posiat least one propeller rblade mounted on the pitch rneans tion of the pitch means each time the portion moves and on at least one of said portions, said propeller from the second extreme position to the first extreme position.

1.2 Y means interconnected with said pitch means for retaining said pitch means in the new station each time the portion moves said pitch means to the new station, and

l1 6. A variable pitch propeller for being mounted on a drive shaft to be driven thereby in a -forward direction and in a reverse direction, said propeller including the combination of hub means having a passage extending therethrough for receiving said shaft, said hub means including a first portion and a second portion movable between first and second extreme positions relative to the first portion,

drive means drivingly connecting said hub means with said shaft for rotatably driving said portions, said drive means being effective to retain said second portion in one of the extreme positions when the hub means is `being driven by said shaft in the forward direction, said drive means being effective to provide for movement of the second portion to the other of said extreme positions when said hub means overruns said drive shaft in a forward direction and when said hub means is driven in a reverse direction, said hub means carrying a sufiicient inertia to move the second portion to said other extreme position when that portion is overrunning said shaft,

pitch means on one of said portions for rotating about said drive shaft with that portion between a series of stations,

means interconnecting said portions with each other for moving said pitch means from one station to the next station when said second portion moves from the first extreme position to Ithe second extreme position,

a one-way drive connected to at least one of said portions and being effective to provide .for said pitch means rotating about said shaft in one direction when the second portion moves from the rst extreme position to the second extreme position and preventing said pitch means from rotating about said shaft in the opposite direction when the second portion moves from the second extreme position to the first extreme position, and

at least one `blade pivotally mounted on at least one of said portions and said pitch means, said blade having a pitch that is determined by the relative angular positions of said portion and said pitch means.

7. A variable pitch propeller for being mounted on 5 at least one propeller blade mounted on said hub means and said pitch means, said propeller lblade being effective to rotate with the hub means about the shaft and to have a pitch determined by the position of the pitch means.

8. A variable pitch propeller for being mounted on a rotatable drive shaft, said propeller including the combination of:

hub means having a passage extending therethrough for receiving said drive shaft and being rotatably driven 'by said shaft,

at least one propeller -blade means,

mounting means on said hub means effective/ to secure said blade on said hub means and to provide for movement of said blade relative t-o said hub about a line normal to said shaft to thereby change the pitch of said blade,

at least one of said means including a portion having a mass movable concentrically about said shaft between a rst extreme position and a second extreme position,

means on said hub means effective to normally retain said portion in the first extreme position and provide for movement of said portion circumferentially of said hub means from the first extreme position to the second extreme position independently of the angular velocity of said hub means only during intervals when the angular acceleration of said mass in one direction exceeds a predetermined amount, and

means inte-rconnecting said portion with said propeller lblade and 'being responsive to the movement of said portion from one of said extreme positions to the other of said extreme positions, said last means bein-g effective to move said blade on said mounting means and vary the pitch of the blade when said portion moves circumferentially on said hub means from said one extreme position to said -other extreme position.

9. A variable pitch propeller for being mounted on a rotatable drive shaft and driven thereby in a forward direction and in a reverse direction, said propeller including the combination of:

a rotating drive shaft, said propeller including the combination of:

hub means having a passage extending therethrough hub means having a passage extending therethrough for receiving said drive shaft, said hub means including at least one portion movable circumferentially about said shaft Abetween a first extreme position 'and a second extreme position,

drive means connecting the hub means to said shaft for rotatably driving said hub means in the forward direction and in the reverse direction,

lost motion meansl connecting the portion to said shaft, said lost ymotion means being effective toprovide for said portion moving relative to the hub and between said two extreme positions,

said drive means ybeing effective to maintain the portion in the tirst extreme position when the drive shaft is driving said hub means in a forward direction,

said lost motion means being responsive to the angular moment of inertia carried by said portion for allowing the portion to move into the second extreme position during intervals when said hub means overruns the drive shaft in a forward direction,

pitch means disposed on said shaft and movable between a plurality of stations, said pitch means being responsive to the movement of the portion from one of the extreme positions to the other of the extreme positions to change the position of the pitch means from one of the stations to a new station each time the portion moves from said one extreme position to said other extreme position,

for receiving said drive shaft, said hub'means including:

first and second members positioned to be disposed concentric about the drive shaft and 'being movable relative to each other, -mounting means on said hub means, at least one propeller rotatably positioned on said mounting means for rotating about a line normal to the axis of said shaft to vary the pitch of said blade,

pitch means interconnected with at least one lof said members and movable between a plurality of stations when that member moves, said pitch means being interconnected with the propeller blade to vary the pitch of the blade in response to the position of the pitch means, and

means constructed and arranged to move Ione of said members when the hub means overruns the drive shaft.

10. A variable pitch propeller for being mounted on a rotating drive shaft, said propeller including the cornbination of hub means having a passage extending therethrough for receiving said drive shaft,

first and second members disposed on the hub means to be concentric about the drive shaft, at least one of said lmembers being rotatable about said shaft relative to the other member,

mounting means on said hub means,

at least one propeller rotatably positioned on said mounting means for rotating about a line normal to said shaft to vary the pitch of said blade,

pitch means on one of said members and movable therewith, said pitch means being interconnected with said propeller blade to vary the pitch of said propeller blade as said one member rotates, and

means constructed and arranged to rotate one of said members when the hub means overruns the shaft..

11. A variable pitch propeller for 'being mounted on a rotating drive shaft, said propeller including the combination of:

hub means having a passage extending therethrough for receiving said drive shaft,

first and second members disposed on the hub means to be positioned concentric about the drive shaft, each of said members being rotatable about said shaft relative to each other,

drive means connecting the hub means to said drive shaft to drive the hub means and to permit the first and second members rotating relative to each other,

mounting means on said hub means,

at least one propeller rotatably carried by said mounting means for rotating about a line normal to said shaft to vary the pitch of said blade, pitch means on the first of said members and movable therewith between a plurality of different stations, said pitch means being interconnected with said propeller blade and effective to set the pitch in accordance with the station that the pitch means is 1n, means effective to rotate the second member in a first direction when the dn've means is driving the hub means and effective to rotate the second member in the opposite direction when the hub means is overruuning the drive shaft, and means interconnecting the first member to the second member to move said first member and the pitch means thereon from one station to the next station each time said second member rotates in one of said directions. 12. A variable pitch propeller for being mounted on a drive shaft and driven thereby, said propeller comprising the combination of:

hub means having a passage extending therethrough for receiving said shaft, said hub means including a first annular member and a second annular member concentric with said passage, said members being rotat-able about said shaft relative to the hub means,

drive means connecting the drive shaft to said hub means for driving said hub means in a forward direction and a reverse direction,

a cam surface on the first annular member,

at least one propeller blade pivotally mounted on said hub means and having a cam follower that engages the cam surface, said blade having a pitch determined by the angular position of the cam surface relative to the hub means,

means effective to move at least the second annular member in a first direction when said hub means overruns the drive shaft in the forward direction and to move the second annular member in the opposite direction when the hub means is driven in the forw-ard direction by the drive means, and

means interconnecting the first member with the second member so as to move the first member and the surface thereon whenever the second member moves in one of said directions.

13. A variable pitch propeller for being mounted on a drive shaft and driven thereby, said propeller comprising the combination of:

hub means having a passage extending therethrough for receiving said shaft, -a first annular member on said hub means, a second annular member on said hub means, said members being concentric with said passage rotatable thereabout relative to each other and to the hub means,

-drive means connecting the drive shaft to said hub means for driving said hub means in a forward direction and in a reverse direction,

a cam surface on the first member and rotatable therewith, said cam surface including a plurality of stations,

at least one propeller blade pivotally mounted on said hub means and having a cam follower, said cam follower being positioned to engage the cam surface and rotate said blade into preselected pitches when the follower engages the successive stations,

means effective to rotate the first annular member in a first direction relative to the hub means when said hub means overruns the drive shaft and to move the first annular member in a second direction relative to the hub means when the hub means is driven by the drive means,

means interconnecting the first and second members together whenever the second member moves in one of said directions, and

means to retain the rst member in a position with the cam follower engaging one of said stations when the second member moves in the opposite direction.

14. A variable pitch propeller for being mounted on a drive shaft to be driven thereby in a forward direction and in a reverse direction, said propeller including the combination of:

hub means having a passage extending therethrough for receiving said shaft, said hub means including a first member and a second member movable between said first and second extreme positions relative to the first member,

drive means drivingly connecting said hub means with said shaft for rotatably driving said hub means, said drive means being effective to retain said second member in one of the extreme positions when the hub means is being driven by said shaft in the forward direction, said drive means being effective to provide for movement of the second member to the other of said extreme positions when said hub means overruns said drive shaft in a forward direction and when said hub means is driven in a reverse direction,

means effective to move the second member to said other extreme position when the hub means is overmnning said shaft,

pitch means rotatably mounted on said first member for rotating about said drive shaft between a plurality of stations,

means interconnecting said first member to the second member for moving said pitch means from one station to the next station when said second member moves from the first extreme position to the second extreme position,

a one-way drive connected to said first member, said one-way drive being effective to provide for said first member and pitch means rotating about said shaft in one direction when the second member moves from the first extreme position to the second extreme position,

a propeller blade mounted on said hub means to rotate about an axis normal to said shaft, and

means on said propeller blade positioned to engage said pitch means and set the pitch of said blade in accordance with the angular position of the pitch me-ans.

15. In combination for varying the pitch or a propeller to control the movements of an object upon an acceleration of the object to a particular speed,

a shaft for driving the propeller,

hub means mounted on the shaft and operatively coupled to the propeller for obtaining a controlled movement of the propeller with the shaft,

first means mounted on the shaft and cooperative with the propeller for varying the pitch of the propeller between rst and second values,

said first means including a ring slotted to engage the propeller,

said slotting in said ring being provided with a configuration to vary the pitch of the propeller in accordance with the position of engagement between the propeller and the slot, and

said rst means being constructed to v-ary the position of engagement between the propeller and the slot upon an initial deceleration of the shaft and a subsequent acceleration of the shaft,

second means mounted on the shaft and responsive to an initial deceleration of the shaft relative to the propeller for preventing the pitch-varying means from changing the pitch of the propeller, and

third means mounted on the shaft and responsive to a subsequent acceleration of the shaft relative to the propeller for obtaining an operation of the pitchvarying means to provide a change in the pitch of the propeller from the rst value to the second value.

References Cited by the Examiner UNITED STATES PATENTS 12/1931 Schroeder l70-160.51 1/1934 Roth 170-160.29 X 1/1936 McDougall 170-160.29 5/1941 Algarsson 170-160.1 6/1943 Frazier 170-160.1 8/1945 Humphreys 170-160.16 9/1960 OConnor 170-160.24

FOREIGN PATENTS 6/ 1934 France. 8/1939 Great Britain.

MARTIN P. SCHWADRON, Primary Examiner.

E. A. POWELL, I R., Assistant Examiner.

Claims

9. A VARIABLE PITCH PROPELLER FOR BEING MOUNTED ON A ROTATING DRIVE SHAFT, SAID PROPELLER INCLUDING THE COMBINATION OF: HUB MEANS HAVING A PASSAGE EXTENDING THERETHROUGH FOR RECEIVING SAID DRIVE SHAFT, SAID HUB MEANS INCLUDING: FIRST AND SECOND MEMBERS POSITIONED TO BE DISPOSED CONCENTRIC ABOUT THE DRIVE SHAFT AND BEING MOVABLE RELATIVE TO EACH OTHER, MOUNTING MEANS ON SAID HUB MEANS, AT LEAST ONE PROPELLER ROTATABLY POSITIONED ON SAID MOUNTING MEANS FOR ROTATING ABOUT A LINE NORMAL TO THE AXIS OF SAID SHAFT TO VARY THE PITCH OF SAID BLADE, PITCH MEANS INTERCONNECTED WITH AT LEAST ONE OF SAID MEMBERS AND MOVABLE BETWEEN A PLURALITY OF STATIONS WHEN THAT MEMBER MOVES, SAID PITCH MEANS