US2875723A - Boat propeller - Google Patents

Boat propeller Download PDF

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Publication number
US2875723A
US2875723A US552754A US55275455A US2875723A US 2875723 A US2875723 A US 2875723A US 552754 A US552754 A US 552754A US 55275455 A US55275455 A US 55275455A US 2875723 A US2875723 A US 2875723A
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boat
shank
frame
blades
propeller
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US552754A
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Richard S Moore
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63HMARINE PROPULSION OR STEERING
    • B63H1/00Propulsive elements directly acting on water
    • B63H1/30Propulsive elements directly acting on water of non-rotary type
    • B63H1/32Flaps, pistons, or the like, reciprocating in propulsive direction

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  • mother ob'fect of this invention is the production of a Boat havingpropellers designed as ducks feet, blades of open and close as the propellers thrust back and fortl'r in water simulating the action of ducks feet while swimming, the power thrust being changed by increasing or decreasing the size of the propeller foot.
  • Figure 1 is a top plan vi'ew of the boat propeller, showing the same attached to" a boat;
  • Figure 2'- is a side. elevational view of the propeller, the boat being shown in seotion;
  • Figure 3 is" an. enlarged ffagmentary side elevational view of the hinged frame of the propeller, a portion of the. turntahl'e and boat being shown in section;
  • Figure 4 is. anenlarged sectional View taken on line 4 4 of Figure 2; p
  • Figure 5 is an enlarged fragmentary vertical sectional view showing the action of the foot shank
  • Figure 6 is a sectional view taken on line 6--6 of Figure 1;
  • Figure 7 is a fragmentary side elevational view.
  • 10 designates a boat to which the. turntable and clamp 11 is secured" by means of the thumb bolts 12.
  • a supporting frame 13 is mounted upon the clamp 11 by means of anupstanding journal 14 in the nature of a square headed bolt, to pivotally secure said frame 13 to the clamp 11.
  • the supporting frame 13 isghinged' tothe head of thebolt 14 bymeans of a pintle 15 which engages the terminals 16 of the frame 13.
  • a primary shaft 17 is journalled transversely at the inboard end of the frame 13, and carries a crank arm 18 at one end thereof upon one side of the frame and a crank arm 19 at the opposite end of the shaft 17 upon the opposite side of the frame 13.
  • a supporting shaft 20 is carried transversely at the outboard end of the frame 13, and oscillating crank arms 21 and 22 are rotatably mounted on the ends of the supporting shaft 20.
  • the crank arms 18 and 19, which are fixed to the primary shaft 17, extend in opposite directions at an angle of 180 relative to each other.
  • the crank arm 18 is connected to the crank arm 21 by means of a link 23 and the crank arm 19 is connected to the crank arm 22, by means of a link 24.
  • a sleeve 25 is fixed to the crank arm 21, and a similar sleeve 26 is fixed to the crank arm 22.
  • a substantially vertical foot shank 27 is slidably carried by the sleeve 25 and carries a transverse anchoring pin 28 which removably fits into the anchoring slot or notch 29, the slot 29 extending longitudinally of and inwardly from the upper end of the sleeve 25 to hold the shank 27 in a selected forwardly ill) 2,875,723 Patented MCenter. 3; lose 2 and rearwardl'y driving position.
  • a coil spring 30 abuts the lower end of the sleeve 25 and is anchored to the shank 27 to yieldably hold the shank 27 in a slot and pin engaging position, as shown in Figure 2.
  • a seoond foot s'hank 31 is slidablly fitted in the sleeve 26 and carries an anchoring slot or notch 32 for receiving an anchoring pin 33 similar to the pin 28.
  • a coil spring 34 similar to the spring 30 is carried by the shank 31.
  • An actuating handle 35 iscarried by the upper end; of the shank to facilitate the adjustment of the shank 27 to a. desired selected driving position for reverse propulsion. This may be done by lifting the shank and thereby lifting the pin 28 out of the slots 29 and then rotating the shank 27 to. a reverse position for reverse propulsion.
  • a similar actuating handle 36 is carried by the shank 3r. V
  • a channeled foot member 37 is pivoted to the lower end of the shank 27 by means of a pivot pin 38, as shown in detail Figure 5.
  • the foot member 37 extends above the pivot pin 38 so as to permit the foot member 37 to swing in one direction when striking an obstruction and to be locked in an opposite direction for pro pulsion.
  • Longitudinally extending hinged fins or blades 39 and 40' are carried by opposite sides of the foot member 37, and are mounted so as to extend at substantially' l ateral positions when the shank 27 is swung in one direction and to fold toward each other when the shank. 27 is swung in a reverse direction. In this way' the fins or blades 39 and 40 will have a driving forcewhen the shank 27 is swung in one direction and will fold toward each other on the return stroke to avoid resistance upon the return stroke.
  • the blades 39 and 40 are secured to the foot member 37 by means of hinges, which hinges are carried by the rear faces of the blades 39 and 40.
  • the forward swing of the blades 39 and 40 to' an open position is limited by the ahut'fr'ient of the inner edges of the blades 39 and 40 against the sides of the foot member 37.
  • the blades 39. and 40 will swinger fold toward each other to avoid resistance.
  • the blades By moving the operating lever up and down, the blades will be moved back and forth in the water, by means of the mechanism illustrated.
  • the blades will open on the thrust stroke and close on the return stroke, thereby duplicating the action of the feet of a duck or other web-footed fowl when swimming.
  • the structure illustrated has sufficient thrust power for pushing, up to and including a three-place small boat in the same manner as a duck would push a floating object with its breast while swimming.
  • the mechanical mechanism herein disclosed constitutes, in the held of propelling equipment, a mechanical duck with all movements de rived from an operating lever 45, which gives the structure the duck-swimming action in every detail.
  • the operating lever 45 which extends inside of the boat 10, allows an operator to steer straight ahead, or in any direction, without changing his position.
  • the blades 40 and 43 alternately lap the center .line of travel between the blades--note the width of blade 43.
  • the shank 31 carries a foot member 41 which is .pivoted at 42 similar to the foot member 37. Fins or blades 43 and 44 are hinged to the foot member in a manner similar to the fins or blades 39 and' 40.
  • the shanks 27 and 31 are set in the positions shown in Figure 2 wherein pins 28 and 33 engage their respective slots 29 and 32 to hold the fins or' blades 39,40, 43 and 44 in forward driving positions.
  • the shanks 27 and 31' are lifted and rotated to a reverse position.
  • the power thrust may be changed by increasing or decreasing the size of the propeller foot.
  • An operating lever 45 is selectively and removably fitted to one end of the primary shaft 17, in the manner shown in Figure l, and by swinging the handle 45 upwardly and downwardly the shanks 27 and 31 will be swung forwardly and backwardly to provide a driving action.
  • the lever 45 may also be swung laterally as indicated by the arrows in Figure 1 to facilitate steering, sincev the supporting frame 13 is pivotally supported upon the turntable 11 by means of the rotatable bolt 14.
  • a spring 46 is carried by the upstanding journal or bolt 14 and the tension thereof may be increased, or decreased by means of the adjusting nut 47.
  • the outer ends of the terminals 16 are beveled, as at 49, on their under faces and the ends 48 of the terminals 16 are fiat and extend at right angles to the longitudinalaxis of the frame 13 to facilitate the holding of theframe 13 in an inoperative upright position shown in Figure 3 when it is desired to elevate the fins or blades to a position out of danger of striking an obstruction or while moving the supporting boat or craft inshore.
  • the device is first clamped to the rear of the boat, near the center as possible.
  • the boat is shoved off by reversing the duck feet.
  • the operator grasps theactuating handles 35 and 36 at the upper ends of the shanks 27 and 31 and then turns the shanks one revolution.
  • the pins 28 and 33 will then automatically fall into the slots 29 and 32 under the force of the springs 30 and 31.
  • Theoperator moves the operating lever 45 up and down to pull the boat out from the bank.
  • the operator then rotates the shanks 27 and 31 to a position for forward movement.
  • the lever 45 may also be swung to the right or left for steering.
  • a hand-operated boat propeller simulating the action of a web-footed fowl comprising a clamp adapted to be attached to a boat, a frame mounted upon said clamp by means of an upstanding journal pivotally securing, said, frame to said clamp for lateral and vertical swinging movement of said frame upon said clamp, a primary shaft extending transversely of and journalled on said frame, an operating handle carried by said primary shaft, a supporting shaft carried in spaced parallel relation relative to said primary shaft upon said frame, crank armsfixed to said primary shaft, an oscillating crank arm rotatably mounted on each end of said supporting shaft, links connecting said crank arms of said primary shaft to the oscillating crank arms of said supporting shaft to oscillate said oscillating crank arms as said handle is swung to oscillate said primary shaft, a sleeve fixed to each oscillating crank arm, a propelling shank carried by each sleeve, means for selectively locking said shanks in a forward anda rear

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Toys (AREA)

Description

R. S. MOORE BOAT PROPELLER Ma rch 3, 1959' 2 Sheets-Shet 1 Fild Dec. 15, 1955 I NVEN TOR I Flame/w 6 Moo/m- ///5 ATTORNEY March 3, 1959 Filed Dec. 13, 1955' R. S. MOORE- BOAT PROPELLER 2 Sheets-Sheet 2 INVENTOR flew/4R2: 67 Moo/PE j/ /Wm W/SATTORNEY United States Patent This invention relates w a boat re arer, and has for one of ohjec'ts' the production of a simple and efficans for propelling a boat around in water with a minimum mount of noise while fishing;
mother ob'fect of this invention. is the production of a Boat havingpropellers designed as ducks feet, blades of open and close as the propellers thrust back and fortl'r in water simulating the action of ducks feet while swimming, the power thrust being changed by increasing or decreasing the size of the propeller foot.
Other objects and advantages of the present invention' will appear throughont' the following specification and clairns.
Figure 1 is a top plan vi'ew of the boat propeller, showing the same attached to" a boat;
Figure 2'- is a side. elevational view of the propeller, the boat being shown in seotion;
Figure 3 is" an. enlarged ffagmentary side elevational view of the hinged frame of the propeller, a portion of the. turntahl'e and boat being shown in section;
Figure 4 is. anenlarged sectional View taken on line 4 4 of Figure 2; p
Figure 5 is an enlarged fragmentary vertical sectional view showing the action of the foot shank;
Figure 6 is a sectional view taken on line 6--6 of Figure 1;
Figure 7 is a fragmentary side elevational view.
By referring to the drawings in detail, it will be seen that 10 designates a boat to which the. turntable and clamp 11 is secured" by means of the thumb bolts 12. A supporting frame 13 is mounted upon the clamp 11 by means of anupstanding journal 14 in the nature of a square headed bolt, to pivotally secure said frame 13 to the clamp 11. The supporting frame 13 isghinged' tothe head of thebolt 14 bymeans of a pintle 15 which engages the terminals 16 of the frame 13.
A primary shaft 17 is journalled transversely at the inboard end of the frame 13, and carries a crank arm 18 at one end thereof upon one side of the frame and a crank arm 19 at the opposite end of the shaft 17 upon the opposite side of the frame 13. A supporting shaft 20 is carried transversely at the outboard end of the frame 13, and oscillating crank arms 21 and 22 are rotatably mounted on the ends of the supporting shaft 20. The crank arms 18 and 19, which are fixed to the primary shaft 17, extend in opposite directions at an angle of 180 relative to each other. The crank arm 18 is connected to the crank arm 21 by means of a link 23 and the crank arm 19 is connected to the crank arm 22, by means of a link 24. A sleeve 25 is fixed to the crank arm 21, and a similar sleeve 26 is fixed to the crank arm 22. A substantially vertical foot shank 27 is slidably carried by the sleeve 25 and carries a transverse anchoring pin 28 which removably fits into the anchoring slot or notch 29, the slot 29 extending longitudinally of and inwardly from the upper end of the sleeve 25 to hold the shank 27 in a selected forwardly ill) 2,875,723 Patented M Iar. 3; lose 2 and rearwardl'y driving position. A coil spring 30 abuts the lower end of the sleeve 25 and is anchored to the shank 27 to yieldably hold the shank 27 in a slot and pin engaging position, as shown in Figure 2. A seoond foot s'hank 31 is slidablly fitted in the sleeve 26 and carries an anchoring slot or notch 32 for receiving an anchoring pin 33 similar to the pin 28. A coil spring 34 similar to the spring 30 is carried by the shank 31. An actuating handle 35 iscarried by the upper end; of the shank to facilitate the adjustment of the shank 27 to a. desired selected driving position for reverse propulsion. This may be done by lifting the shank and thereby lifting the pin 28 out of the slots 29 and then rotating the shank 27 to. a reverse position for reverse propulsion. A similar actuating handle 36 is carried by the shank 3r. V
A channeled foot member 37 is pivoted to the lower end of the shank 27 by means of a pivot pin 38, as shown in detail Figure 5. The foot member 37 extends above the pivot pin 38 so as to permit the foot member 37 to swing in one direction when striking an obstruction and to be locked in an opposite direction for pro pulsion. Longitudinally extending hinged fins or blades 39 and 40' are carried by opposite sides of the foot member 37, and are mounted so as to extend at substantially' l ateral positions when the shank 27 is swung in one direction and to fold toward each other when the shank. 27 is swung in a reverse direction. In this way' the fins or blades 39 and 40 will have a driving forcewhen the shank 27 is swung in one direction and will fold toward each other on the return stroke to avoid resistance upon the return stroke.
By considering Figure 4, it will be noted that the blades 39 and 40 are secured to the foot member 37 by means of hinges, which hinges are carried by the rear faces of the blades 39 and 40. The forward swing of the blades 39 and 40 to' an open position is limited by the ahut'fr'ient of the inner edges of the blades 39 and 40 against the sides of the foot member 37. As the shank 27 is swung toward the rear end of the boat 10 the blades 39. and 40 will swinger fold toward each other to avoid resistance. When the shank 27 is swung in a reverse direction away from the rear end of the boat 10, the blades 39 and 40 will swing away from each other from the relative closed dotted line position, to the open full line slight scoop-shape position shown in Figure 4, to provide an efficient propelling means. The foot member 37, should it strike an obstruction, may swingrear- Wardly on its pivot pin 38, but its forward swing. be liiriited by the abutment of the upper end of the shoe 3'7 against the lower end ofthe shank 27, above the pivot pin 38.
By moving the operating lever up and down, the blades will be moved back and forth in the water, by means of the mechanism illustrated. The blades will open on the thrust stroke and close on the return stroke, thereby duplicating the action of the feet of a duck or other web-footed fowl when swimming. The structure illustrated has sufficient thrust power for pushing, up to and including a three-place small boat in the same manner as a duck would push a floating object with its breast while swimming. The mechanical mechanism herein disclosed constitutes, in the held of propelling equipment, a mechanical duck with all movements de rived from an operating lever 45, which gives the structure the duck-swimming action in every detail.
The operating lever 45 which extends inside of the boat 10, allows an operator to steer straight ahead, or in any direction, without changing his position. The blades 40 and 43 alternately lap the center .line of travel between the blades--note the width of blade 43. The
40 and 43 will just pass without touching, while one is closed and the other open. The overlap travel eliminates all zig-zag movement. This is another duckswimming principle.
The shank 31 carries a foot member 41 which is .pivoted at 42 similar to the foot member 37. Fins or blades 43 and 44 are hinged to the foot member in a manner similar to the fins or blades 39 and' 40. When driving the boat forwardly, the shanks 27 and 31 are set in the positions shown in Figure 2 wherein pins 28 and 33 engage their respective slots 29 and 32 to hold the fins or' blades 39,40, 43 and 44 in forward driving positions. When it is desired to reverse the direction of travel of the boat, the shanks 27 and 31'are lifted and rotated to a reverse position.
The power thrust may be changed by increasing or decreasing the size of the propeller foot.
An operating lever 45 is selectively and removably fitted to one end of the primary shaft 17, in the manner shown in Figure l, and by swinging the handle 45 upwardly and downwardly the shanks 27 and 31 will be swung forwardly and backwardly to provide a driving action. The lever 45 may also be swung laterally as indicated by the arrows in Figure 1 to facilitate steering, sincev the supporting frame 13 is pivotally supported upon the turntable 11 by means of the rotatable bolt 14.
I A spring 46 is carried by the upstanding journal or bolt 14 and the tension thereof may be increased, or decreased by means of the adjusting nut 47. The outer ends of the terminals 16 are beveled, as at 49, on their under faces and the ends 48 of the terminals 16 are fiat and extend at right angles to the longitudinalaxis of the frame 13 to facilitate the holding of theframe 13 in an inoperative upright position shown in Figure 3 when it is desired to elevate the fins or blades to a position out of danger of striking an obstruction or while moving the supporting boat or craft inshore.
The tension of the spring 46 will tend to hold the frame,
13 in its vertical position when the flat ends of the terminals 16 rest upon the upper face of the turntable or clamp 11.
The operation of the device is as follows:
The device is first clamped to the rear of the boat, near the center as possible. The boat is shoved off by reversing the duck feet. To do this, the operator grasps theactuating handles 35 and 36 at the upper ends of the shanks 27 and 31 and then turns the shanks one revolution. The pins 28 and 33 will then automatically fall into the slots 29 and 32 under the force of the springs 30 and 31. Theoperator moves the operating lever 45 up and down to pull the boat out from the bank. The operator then rotates the shanks 27 and 31 to a position for forward movement. The lever 45 may also be swung to the right or left for steering.
For fishermen who row backwardly, the shanks are reversed to provide a backward movement. Since the boat propeller is equipped with two feet, when the lever 45 is moved up and down there is provided an even thrust simulating the exact manner in which a duck swims.
It should be understood that certain detail changes in the mechanical construction and arrangement of parts may be employed without departing from the spirit of the invention, so long as such changes fall within the scope of the appended claims.
Having described the invention, what I claim as new 1. A hand-operated boat propeller simulating the action of a web-footed fowl comprising a clamp adapted to be attached to a boat, a frame mounted upon said clamp by means of an upstanding journal pivotally securing, said, frame to said clamp for lateral and vertical swinging movement of said frame upon said clamp, a primary shaft extending transversely of and journalled on said frame, an operating handle carried by said primary shaft, a supporting shaft carried in spaced parallel relation relative to said primary shaft upon said frame, crank armsfixed to said primary shaft, an oscillating crank arm rotatably mounted on each end of said supporting shaft, links connecting said crank arms of said primary shaft to the oscillating crank arms of said supporting shaft to oscillate said oscillating crank arms as said handle is swung to oscillate said primary shaft, a sleeve fixed to each oscillating crank arm, a propelling shank carried by each sleeve, means for selectively locking said shanks in a forward anda rearward driving position in said sleeves, and said handle providing 'meansto facilitate simultaneous lateral swinging of said frame to steer a boat upon which said clamp is mountedand to propel the boat by swinging said propelling shanks through the rotation of said primary shaft.
2. A device as defined in claim 1, wherein said frame is provided with an abutment at one end thereof and at right angles to the longitudinal axis of said frame- References Cited in the file of this patent UNITED STATES PATENTS 150,915 Von Elsncr May 12, 1874 1,197,239 Sinclair Sept. 5, 1916 2,507,469 Hanson May 9, 1950 2,548,407 Tabbert Apr. 10, 1951
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4568290A (en) * 1984-04-02 1986-02-04 Brown George L Lateral thrust drive for watercraft
WO2005077753A1 (en) * 2004-02-12 2005-08-25 Halfdan Endresen Device for propulsion, stabilisation and steering of a vessel
US7396267B1 (en) 2006-08-24 2008-07-08 Parker Jack W Watercraft rowing fin system
US20090215339A1 (en) * 2008-02-27 2009-08-27 Henry Detweiler Watercraft Paddle Propulsion System
US20110039460A1 (en) * 2009-08-13 2011-02-17 Jack Parker Internally mounted watercraft rowing fin system

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US150915A (en) * 1874-05-12 Improvement in the means for propelling vessels
US1197239A (en) * 1916-06-08 1916-09-05 David H Sinclair Propeller for boats.
US2507469A (en) * 1948-01-02 1950-05-09 William O Hanson Boat propelling means
US2548407A (en) * 1948-08-06 1951-04-10 Paul C Tabbert Rowing and steering device for boats

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US150915A (en) * 1874-05-12 Improvement in the means for propelling vessels
US1197239A (en) * 1916-06-08 1916-09-05 David H Sinclair Propeller for boats.
US2507469A (en) * 1948-01-02 1950-05-09 William O Hanson Boat propelling means
US2548407A (en) * 1948-08-06 1951-04-10 Paul C Tabbert Rowing and steering device for boats

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4568290A (en) * 1984-04-02 1986-02-04 Brown George L Lateral thrust drive for watercraft
WO2005077753A1 (en) * 2004-02-12 2005-08-25 Halfdan Endresen Device for propulsion, stabilisation and steering of a vessel
US7396267B1 (en) 2006-08-24 2008-07-08 Parker Jack W Watercraft rowing fin system
US20090215339A1 (en) * 2008-02-27 2009-08-27 Henry Detweiler Watercraft Paddle Propulsion System
US7803027B2 (en) * 2008-02-27 2010-09-28 Henry Detweiler Watercraft paddle propulsion system
US20110039460A1 (en) * 2009-08-13 2011-02-17 Jack Parker Internally mounted watercraft rowing fin system
US8419487B2 (en) 2009-08-13 2013-04-16 Jack Parker Internally mounted watercraft rowing fin system

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