US2131490A - Toy aeroplane propeller mounting - Google Patents

Description

Sept. 27, 1938. N. E. WALKER TOY AEROPLANE PROPELLER MOUNTING Filed Sept. -4, 1936 Patented Sept. 27, 1938 UNITED STATES PATENT OFFICE 19Clalms.

ler to be perforated or otherwise weakened t I secure a hub or journal thereto;

2. which is resiliently mounted in the fuselage '15 so that the propeller can be easily twisted out of its operating plane to prevent breakage when said toy aeroplane strikes the ground nose first, which mounting firmly holds the propeller and the hub to prevent relative rotation thereof, and 20 which structure is adapted to permit the propeller to be moimted on the fuselage without unshipping or removing said propeller in packaging said toy aeroplane, said features being present in a mounting which automatically and resiliently 25 arranges the propeller at its proper flying angle;

3. One which imposes increased resistance to the rotation of the propeller under the influence of a twisted band motor when said band motor is twisted to maximum distortion, said resistance 30 retarding the effective speed of rotation of said propeller, said moimting progressively decreasing the resistance as said band motor untwists thereby permitting freer rotation of said propeller and securing a more uniform overall flying speed 35 when used with an uncoiling rubber band which gives varying torque to the propeller;

4. A mounting which permits the use of simpl light and eillcient anti-friction bearings for the propeller involving negligible expense and eill- 4 cient action;

5. A moimting which provides a convenient detachable support for thelanding gear and its support which landing gear engages said mounting and tends to increase the engagement between said mounting and the fuselage of said toy aeroplane; and

6. A mounting which permits the use of a relatively small quantity of metal and permits the use on the remainder of said toy aeroplane of 50 light balsa wood and thin propellers to increase Fig. 1 is a perspective view of a toy aeroplane embodying my invention;

Fig. 2 is a fragmentary plan view of the propeller mounting with portions of the fuselage and propeller shown joined thereto;

Fig. 3 is an elevation of the forward end of the fuselage, the propeller and its mounting, illustrating how the propeller can be tipped angularly out of its normal flying plane in said mounting thru the resilient manner in which said propeller is seated in said mounting;

Fig. 4 is a side elevationof said mounting, a portion being shown broken away to disclose details of construction; v

I Fig. 5 is a longitudinal section thru said mounting and the associated parts taken substantially on the line 5-5 in Fig. 4;

Fig. 6 is an enlarged sectional view thru the propeller hub, the anti-friction bearings and the forward end of the'propeller mounting, and

Fig. 7 is a sectional view taken'on the line 1-1 in Fig. 6 thru the anti-friction bearings and illustrates the construction thereof.

A toy aeroplane embodying my invention comprises a fuselage a which may be in the form of an elongated rectangular wooden section. Extending thru a slot 0. formed in said fuselage is a single wing structure b. The tail structure comprises two members c andd, secured to the rear end of said fuselage, the member'c extends 80 vertically in a slot a2 formed at the rearward edge of said fuselage and a horizontal tail member dis securedto the under side of said fuselage by the rubber band or similar element e.

At the forward end of the fuselage a nose piece ,f is provided which constitutes the principalportion of the propeller mounting. A .tubular hub g is joumalled in the depending forward end of the nose piece I being journalled in a hole h formed in said forward end. formed of an integral section of metal U-shaped in section. The principal web I! overlies the tapered forward end a3 of-the fuselage, this being illustrated in Fig. 4.

Laterally projecting flanges l3 and 14 extend 4.5 downwardly as 'is indicated most clearly in Figs. 1 and 3,. and engage the' sides of said tapered forward end a3. Underlying said forward end are two inwardly bent lips 15 and I! which encircle said underside and hold the nose piece in 50 place. Extending 'rearwardly from the flanges f3, and fl are spring-like clamps fl and 18, as is indicated in Figs. 2 and 5. Said clamps define two laterally alined grooves i.i' for accommodating a bifurcated resilient landing gear sup- 5s Said nose piece is 40 port a. Said landing gear support if preferably is made of a single piece of wire, such for example as piano wire, and at the middle an inverted U-shaped structure 7" is formed. Said U-shaped structure overlies the web 2 of the nose piece and engages and grips the clamping elements I! and f8 between them. Said U-shaped structure seats in the grooves ii and thus is prevented from shifting laterally on said nose piece. At the lower end, wheels lc-lc' are provided whichare carried by laterally ofl'set projections 7'2 at the ends of the wire forming the landing support gear The forward end of said nose piece spreads and broadens out into a mushroom head in which the hole h is formed. Said mushroom-shaped head provides adequate bearing for maintaining the hub g in its proper angular position with respect to the longitudinal dimension of the fuselage to provide correct flying angle for said aeroplane. The twisted rubber band rotor e is secured at its rearward end upon a hook I depending downwardly from the fuselage. Said rubber band motor preferably is arranged in endless form and the rearward loop extends about said hook and the forward end passes thru the bore of the tubular hub 1 and is looped about the middle of the propeller m. The propeller is made of relatively thin strong material, but ofuniform thickness. This permits the propeller to be stamped out of sheets of material and twisted to proper shape rather than requiring said propeller to be shaped out of a relatively large block of wood with the attendant waste and manufacturing .expense to secure a thick hub. 1

Said tubular hub is provided with slots g of suflicient width to accommodate the propeller. Said slots are adapted to fit snugly against the sides of the propeller so as to prevent substantial play. Said slots are arranged relatively angularly to each other and to the axial dimension of the tubular hub so that the propeller is not required to have a flat central section to seat in said slots. Said slots extend from the forward edge of the propeller rearwardly a sufllcient distance to accommodate the width of the central part of said propeller. Extending rearwardly of said propeller is a laterally formed shoulder 92 formed in the hub g. Said shoulder preferably is formed by crimping the material of which the tubular hub is formed to deflne a laterally extend-.- ing exterior flange of double the thickness of the walls of said hub. Said flange is of sumciently great diameter to provide a solid shoulder for alining the hub correctly with respect to the nose piece.

I preferably provide an anti-friction bearing 1|. between said shoulder 92. and the forward mushroom shaped head 1! of the nosepiece. Said antifriction bearing is preferably constructed of two opposed cups n and M. The cup n is of slightly larger diameter than the cup 112 and thus the cup n2 nests within the cup 11'. as is shown in Fig. 6.

..Ball bearings n3 arehoused within said cups in a flat race n4. Said race n4 is preferably 'crimped within the rim of the cup 112 to rotate therewith. When said anti-friction bearing is in place, the

rubber band as is indicated in Fig. 5. As has previously been stated, said rubber band is preferably arranged in endless form and extends about the central portion of said propeller. Said propeller is provided with a lateral projection m at its middle which is substantially of the same width as the diameter of the tubular hub so as to flt into said bore and to hold said propeller against lateral shifting in the slot y when said propeller is resiliently held in said slots by the action of the rubber band motor.

When the rubber band motor is arranged about said propeller the latter is permitted to be tipped easily as is shown in Fig. 3, if the rubber band is not twisted severely to shorten its overall length. This permits the propeller to be swung out of its normal position to permit easy packaging of the said toy aeroplane without removing said propeller. The propeller is prevented from shifting laterally by said central offset portion 1n. Said propeller structure also permits the propeller to be moved angularly to prevent breakage of said propeller if said toy aeroplane strikes a solid object at the end of its flight, or ends nose down on the ground or otherwise strikes some solid object.

One of the diillculties in using a rubber band motor is that its distortion whentwisted tends to provide greater torque when it is twisted to its maximum degree and a decreasing torque as said rubber band becomes untwisted. This tends to cause the propeller to be rotated at a higher speed at the commencement of flight and a correspondingly lower speed as the untwisting continues. By securing the propeller directly to the rubber band so that it tends to become seated more tightly as the overall length of the rubber band diminishes when twisted, a corresponding increase in resistance to rotation is secured. Thus, when the rubber band is twisted to its maximum degree it imposes a correspondingly increased friction to prevent rotation of said propeller. As said band becomes, untwisted said friction decreases somewhat in proportion to the force exerted by the partly untwisted rubber band. This structure causes the speed of the propeller under the influence of said rubber band to become more umform over a sustained flight and increases the flying ability of said toy aeroplane. Anti-friction bearings are interposed to minimize said friction and-do not disturb this relationship but do prevent said friction from becoming too great to prevent the propeller from rotating freely.

The wings and tail structure and fuselageof said toy aeroplane are preferably constructed of balsa wood and the nose piece is preferably constructed of relatively thin stamped sheet metal, such for example, as thin copper or aluminum. The tubular hub bearings are alsoconstmcted of relatively light materials of thin sections and the propeller may be constructed of hard wood or ply wood. The propeller being of uniform thickness may be easily and inexpensively stamped from a sheet of uniform thickness and distorted to proper pitch.

I claim:

1. In a'toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mmmted at the forward end of said fuselage anda resilient band motor for rotating said propeller, a mountingfor said propeller comprising a nose piece secured to said fuselage having a seat formed in its forward end a slotted hub journnalled therein, said propeller being of uniform ll peller being of uniform thickness releasably en- 8 -81118 said seat at its middle, said band motor extending longitudinally of said hub about said propeller, and resiliently holding said propeller in its seat.

3. In a toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward. end of said fuselage and a resilient band motor for rotating said propeller,a mounting for said propeller including a tubular hub rotatably secured to said fuselage having a slotted seat formed in its forward end, said propeller being of uniformthickness releasably engaging said seat at its middle, said band motor extending thru the bore of said tubular hub, about said propeller and resiliently holding said propeller in its seat.

4. ma toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a moimting for said propeller including a having a seat formed in its forward end, said propeller being of. uniform thickness engaging said seat at its middle, said band motor extending longitudinally of said hub, about said propeller, and resiliently holding said propeller in its seat.

-5. In a toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotat'ablymounted at the forward end of said fuselage and a resilient band motor for rotating said pro-- peller, a nose piece secured to the forward end of said fuselage constituting amounting for said propeller, said nose piece provided with a journal formed therein, a member journalled in said nose piece, said propeller mounted in a seat formed in said member, said band motor extending long!- tudinally of said member and engaging the propeller at its middle, resiliently holding said propeller in said seat formed in said member.

6. In a toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece provided with a journal formed therein, a member journalled in said nose piece, said propeller mounted in a seat formed in said member, said band motor extending longitudinally of said member and engaging the propeller at its middle, resiliently holding said 'propeller in said seat formed in said member, alateral shoulder on said member operatively restraining the lateral displacement of said member with respect to said nose piece.

7. In a toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece provided with a journal formed therein, a member journalled in said nose 75' piece, said propeller mounted in a seat formed in said member, said'band motor extending longitudinally of said member and engaging the propeller at its middle, resiliently holding said propeller in said seatformed in said member, a lateral shoulder on said member operatively restraining the lateraldisplacement of'said member with respect to said nose piece anda bearing interposed between said shoulder and said nose piece.

8. In a toy aeroplane comprising'a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, .a nose piece secured to the forward end of said fuselage constituting a mountingfor said propeller, said nose piece provided with a journal formed therein, a member journalled in said nose piece, said propeller mounted in a seat formed in said member, said band motor extending longitudinally of said member ande m g the propeller at its middle, resiliently holding said propeller in said seat formed in said member, a lateral shoulder on said member operatively restraining the lateral displacement of said member with respect to said nose piece, and an anti-friction bearing interposed between said shoulder and said nose piece.

9. In a toy aeroplane comprising a fuselage, I wing and tail structures, a propeller blade rotatatudinally of said member and engaging the propeller at its middle, resiliently holding said propeller in said seat formed insaid member, a lateral shoulder on said member operatively re straining the lateral displacement of said member with respect to said nose piece, an anti-friction bearing interposed between said shoulder and said nose piece, said anti-friction bearing comprising two opposed cups held in operative relation by an enlargement of said member.

10.1In a toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilientband' motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece provided with a journal formed therein, a slotted tubular member journalled in said nose piece, said propeller mounted in said slotted member, said band motor extending thru said tubular member and engaging the propeller at its middle, resiliently holding said propeller in said slotted member.

11. In a. toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece provided with a mushroom-shaped depending forward end and a journal formed therein, a slotted tubular member straining the lateral displacement of said member with respect to said nose piece.

12. In a toy aeroplane comprising a fuselage,- wing and tail structureaa propeller blade rotatably mounted at the forwardend of said fuselage and a'resilient band motor for rotating said propeller, a nose piece securedto the forward end of Y said fuselage constituting a mounting for said peller in said slotted member, a lateral shoulder on said tubular member operatively restraining the lateral displ t iment of said member with respect to said nose piece.

13. In a toy aeroplane comprising a fuselage, wing and tail. structures, a propeller blade, rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a .nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece being of inverted U- shaped section and provided with a journal formed therein, a member journalled in said nose piece, said propeller mounted in a seat formed in said member.

14. In a toy-aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted 'at the forward end of said-fuselage and a resilient band motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece provided with-a depending forward end and a journal formed therein extending below said fuselage, a member Journailed in said nose piece, said propeller mounted in a seat formed in said member, said band motor underlying said fuselage and extending longitudinally of said member and enga in the propeller at its middle, resiliently holding said propeller in said seat formed in said member.

15. In a toy aeroplane comprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, said nose piece provided with a mushroom-shaped depending forward end and a Journal formed therein extending below said fuselage, a member Journalled in said nose piece, said propeller mounted in a seat formed in said member, said band motor underlying said fuses lage andextending longitudinally of said member I and engaging the propeller at its middle, resiliently holding said propeller in said seat formed in said slotted member. 4

16. In a toy aeroplane comprising a fuselage, wing and tail structuresa propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller-{a nose piece clamped to the forward end of said fuselage constituting a mounting for said propeller, two opposed clamping members on said nose piece gripping saidforward end between H g 1'7. In atoy aeroplane comprising a fuselage, wing and tail'structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a nose piece secured to the forward end of said fuselage constituting a mounting for said propeller, laterally alined grooves formed in said nose piece, a resilient bifurcated member constituting wheel supports, ,said member provided at its middle with a closely bent U-shaped structure straddling said nose piece and seated in said 18. In a toy-aeroplanecomprising a fuselage, wing and tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a nose piece clamped to the forward end of said fuselage constituting a mounting for said,

propeller, vtwo opposed clamping members on said nose piece gripping. said forward end between them, laterally alined grooves formed in said clamping members of said nose piece, a resilient bifurcated member constituting wheel supports, said member provided at its middle with a closely bent U-shaped structure straddling said clamping members of said nose piece and seated in said grooves.

19. In a toy aeroplane comprising a fuselage, wingand tail structures, a propeller blade rotatably mounted at the forward end of said fuselage and a resilient band motor for rotating said propeller, a now piece clamped tothe forward end of said fuselage constituting a mounting for said propeller, two opposed clampingmembers on said nose piece ripping said forward end between them, laterally alined grooves formed in said clamping members of said nose piece, a resilient bifurcated member constituting wheel supports, said member provided at its middle with a closely bent u-shaped structure straddling said clamping members of said nose piece and seated insaid grooves and gripping said nose piece, tending to force the latter into tighter engagement with said fuselage.

NEVILLES E. WALKER.

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