US3757461A

US3757461A - Impact-damage-resistant, propeller-driven toy

Info

Publication number: US3757461A
Application number: US00278507A
Authority: US
Inventors: R Chang; T Yamasaki; W Staats; D Bosley
Original assignee: Mattel Inc
Current assignee: Mattel Inc
Priority date: 1972-08-07
Filing date: 1972-08-07
Publication date: 1973-09-11
Anticipated expiration: 1990-09-11
Also published as: CA943344A; GB1396619A; JPS4944836A; DE2305915A1

Abstract

An impact-damage-resistant nose construction for use with propeller driven flying toy aircraft, the nose construction including an energy absorber connected to the fuselage and including a portion which is positioned between the propeller and the power plant with a movable coupling connecting a propeller shaft to the power plant so that the propeller may move axially relative to the power plant when the energy absorber is deformed by an impact.

Description

{mite States Patent Chang et a1.

[ 1 Sept. 11, 1973 1 1 lMPACT-DAMAGE-RESISTANT,

PROPELLER-DRIVEN TOY [75] lnventors: Richard S. Chang, Rolling Hills Estates; William A. Staats, Torrance; Denis V. Bosley, Palos Verdes Peninsula", Toshio Yamasaki, Gardena, all of Calif.

[73] Assignee: Mattel, Inc., Hawthorne, Calif.

[22] Filed: Aug. 7, 1972 [21] Appl. No.: 278,507

[52] U.S. Cl 46/243 AV, 46/78 [51] Int. Cl. A63h 27/00, A63h 33/26 [58] Field of Search 46/76, 78, 81, 243 AV; 244/1 [56] I References Cited UNITED STATES PATENTS 3,232,564 2/1966 Benson 46/78 Primary ExaminerLouis G. Mancene Assistant ExaminerR0bert F. Cutting Att0rneySeymour A. Scholnick [57] ABSTRACT An impact-damage-resistant nose construction for use with propeller driven flying toy aircraft, the nose construction including an energy absorber connected to the fuselage and including a portion which is positionedbetween the propeller and the power plant with a mov-.

able coupling connecting a propeller shaft to the power plant so that the propeller may move axially relative to the power plant when the energy absorber is deformed by an impact.

20 Claims, 12 Drawing Figures PATENTED SEP I I973 SHEET 1 BF 5 PATENTEDSEPI i ma sum 2 0F 5 sum 3 (IF 5 PATENTED SEP] 1 I975 IMPACT-DAMAGE-RESISTANT, PROPELLER-DRIVEN TOY BACKGROUND OF THE INVENTION The background of the invention will be set forth in two parts.

FIELD OF THE INVENTION The present invention pertains generally to the field of toys and more particularly to impact-damageresistant, propeller-driven toys subject to impact with the ground and other objects.

DESCRIPTION OF THE PRIOR ART The probability that flyable toy aircraft will sooner or later impact the ground or structures situated thereon and be severely damaged, is well established. In nearly all such instances, the impact is incident on the front end of the craft. The force may damage the propeller, and the toys air frame and power plant housed therein.

SUMMARY OF THE INVENTION In view of the foregoing factors and conditions characteristic of the prior art, it is a primary object of the present invention to provide a new and improved impact-damage-resistant, propeller-driven toy.

Another object of the present invention is to provide a relatively lightweight, resiliently-deformable, impactdamage-resistant flyable toy aircraft.

Still snother object of the present invention is to provide an impact-damage-resistant, propeller-driven toy that includes structure rotationally coupling the toys power plant to its propeller while allowing relative movement therebetween.

It is still another object of the present invention to provide a nose construction for motor-powered, propeller-driven toys that allows the propeller shaft to move both inwardly and laterally upon severe impact without damaging the shaft or the drive mechanism which rotates the shaft and propeller.

According to the present invention, two embodiments of an impact-damage-resistant nose construction are provided for use with motor-powered and propeller-driven toys, such as toy aircraft. One embodiment includes a propeller shaft housing having a circular cross-sectioned hollow elongated nose portion with a propeller-facing forwardend. The housing also includes a circular-cross-sectioned, increased-diameter, hollow rear portion, the elongated nose portion and the rear portion being joined by a hollow, integral, truncated cone portion exhibiting a variable resistance to compressive load. The truncated cone portion slopes forward from its larger-diameter edge, and it, along with the rear and nose portions are axially aligned with a common longitudinal axis, namely the rotational axis of the propeller shaft contained therein. Preferably, the elongated nose portion is a hollow truncated cone with its smaller end located at the forward part of the housing, the outer surface of this elongated nose portion preferably including a plurality of uniformly spaced longitudinal ribs.

In a second and third embodiment of the present invention, a fuselage frame has a forward end and a rear end. A power plant is mounted in the frame, and energy absorbing means is connected to the frame at the forward end of the fuselage frame for absorbing impact energy incident at the front of the fuselage. Also ineluded is power transmitting means operatively coupled to the propeller and to the power plant through the energy absorbing means for transmitting rotational power from the power plant to the propeller and allowing relative movement therebetwen.

The power transmitting means may include a coupling structure having oppositely disposed shaft coupling portions, the portions coaxially overlapping to allow relative axial movement therebetween, but being keyed to maintain rotational integrity.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by making reference to the following description, taken in conjunction with the accompanying drawings in which like reference characters refer to like components in the several views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view, partially in section, illustrating a first embodiment of the inventive structure and a flying toy aircraft carrying same;

FIG. 2 is a perspective view showing, in enlarged form, the forward portion of the toy aircraft of FIG. 1;

FIG. 3 is an enlarged sectional view of the nose portion of the aircraft structure taken along line 3-3 of FIG. 1;

FIG. 4 illustrates the reaction of the propeller housing structure of FIG. 1 to initial impact forces on the propeller;

FIG. 5 illustrates how the propeller housing absorbs the impact forces without allowing the propeller shaft and the power train coupled thereto to be damaged;

FIG. 6is an elevational view of a modified propeller shaft housing structure;

FIG. 7 is an end view of the propeller shaft housing structure of FIG. 6;

FIG. 8 is an elevational view, partially broken away, of the forward portion of a flyable toy aircraft constructed in accordance with a second embodiment of the present invention;

FIG. 9 is a plan view of that aircraft illustrated in FIG. 8;

FIG. 10 is a plan view of the toy, similar to that seen in FIG. 9, but illustrating the change in relative positions of the crafts components upon impact;

FIG. 11 is a partially broken away elevational view of the front end portion of a flyable toy aircraft constructed in accordance with a third embodiment of the present invention; and

FIG. 12 illustrates impact-caused deformation of the forward portion of the toy seen in FIG. 11 as would be caused by the toys impact with the ground, for example.

portion of the flyable toy DESCRIPTION OF THE INVENTION Referring again to the drawings, and more particu larly to FIG. 1, there is shown a propeller-driven toy, such as a flyable toy aircraft 11 having conventional wings 13, a body or fuselage 15, a cowling l7, and a propeller 19. The fuselage may be provided with simulated windows 21 and a windshield 23 and other simulated fixtures and appendages such as a landing gear, not here shown for the sake of simplicity.

Referring now also to FIG. 2, it can be seen that a forward housing or nose cone portion 25 is detachable from the remainder of the crafts body or fuselage 15. The portion 25 has a forward end 27 and an attachment portion 29, the latter including attachment means (described in more detail later) for removably attaching the portion 25 to the toy aircraft 11. The attachment portion basically comprises a transverse plate or wall 31 that lies in a plane orthogonal to the longitudinal axis 33 of a propeller shaft 35 rotatably disposed in the portion 25 and extending beyond the forward end 27 and seated at its threaded end 36 in a threaded bore 37 in the propeller 19. In this embodiment, the wall 31 is generally rectangular and has a lower indexing portion 41 registering with lower holding brackets 43 which are an integral part of an attachmentbulkhead or frame 45 fixedly attached to a forward portion of the fuselage 15 (note arrows 47 in FIG. 2).

The bulkhead 45 has an outer edge 49 which conforms to the cross section of the fuselage 15 and a generally rectangular central opening 51. The frame 45 also includes forwardly extending positioning members 53 and a resilient holding tab 55 with an inwardly extending lip portion 57. The tab 55 and the members 53 are preferably an integral part of the single plastic molded bulkhead 45, which frame may be either an integrally molded part of the aircraft fuselage or permanently attached thereto by conventional bonding means such as a plastic cement, for example. In the latter case, frame 45 will include a flange portion 59 which slidably fits within the fuselage l and bonded thereat. Slots 63 are provided in the fuselage to accommodate a pair of rubber band tie down members 65, the rubber bands (not shown) being used to hold the wing 13 in place.

From'FIG. 2, it can be seen that the portion 25 is removably attached to the fuselage by first inserting the indexing portion 41 into the holding brackets 43 and the upper edge 67 of the plate 31 is then moved into contact with the holding tab 55, as indicated by arrows 69. Additional rearward pressure on the plate 31 or the lifting of the tab 55'will allowthe lip portion 57 to slide over the edge 67 and then down to hold the plate against the positioning members 53. These members 53 may be sloped and dimensioned to position the longitudinal axis 33 of the propeller shaft 35 relative to the longitudinal axis 70 of the fuselage for certain desired effects such as counteracting the propeller torque for straight powered flight, with the control surfaces (not shown) in their neutral position, for example. This technique is well-known in the art and will not be described here in detail.

Extending rearwardly from the wall 31 are a pair of spaced parallel broadly flat arms 71 which terminate at a forward wall 73 of a rectangular open frame 75. The inner face 77 of the plate 31 and the forward face 79 of the wall 73 carry cylindrical lip portions 81 adapted to fit about and fixedly hold in place a powerful miniature electric motor 83, best seen in FIG. 1. Extending in back of a rear wall 85 of the frame 75 is a somewhat smaller battery-compartment, open-frame arrangement 87 which securely holds, in this embodiment, a pair of tandemly mounted, electrically series connected, rechargeable nickel-cadmium batteries 89, 91. This battery of cells 89 and 91 may be considered as a single battery arrangement 93 with a positive battery terminal 95 and a negative battery terminal 97 (the outer case of the lower cell 91).

A positive contact member 99 of a metal conductive material such as brass, for example, is bent to extend between and is permanently attached and electrically connected to one input terminal 100 of the motor 83 and to the positive battery terminal 95 of the battery arrangement 93. The member 99 also extends beyond the battery compartment 87 and finally terminates at a V-shaped positive charging plug tip contact 101 seated on supporting edges 103 of a recharging plug enclosure member 105 mounted at the rear wall 107 of the frame 87. A lower wall 109 of the frame 87 is in the form of a hollow conduit having a rectangular cross section which slideably houses an elongated switch member 111 with a switch operating depending tab 113. The member 111 includes a travel limit projection 115 moving in an elongated slot 117 in a lower wall portion 119 of the wall 109. A plug accepting hole 121 is also provided in the member 111 which hole registers with a recharging plug passageway 123, defined by the enclosure member 105, only when the member 111 is in its off position (extreme forward position).

The switch member 111 is also provided with an upwardly extending tab 125 adjacent the forward end thereof. The tab 125 pushes a negative battery contact end 127 of a conductive negative contact member 129 into physical and electrical contact with the negative battery terminal 97 against the self-biasing resiliency of the member 129, only when the tab 113 is pushed in a rearward direction to its extreme rear or on" position, as indicated by arrow 13]. Since the negative contact member 129 is permanently connected to a second motor input terminal 133, the electrical supply circuit to the motor 83 is complete when the contact end 122 is forced to touch the negative battery terminal 97, and the motor is thus activated.

In order the charge the battery arrangement 93, a conventional charging plug (not shown) having a tubular sleeve and an insulated tip is inserted through the hole 129 into the passage 123 until the plugs tip (positive polarity) contacts and registers with the tip contact 101, and the plugs sleeve (negative polarity) lies against and makes electrical contact with the negative battery terminal 97, which is the outer case of the cell 91. Once the battery arrangement has been charged, the charging plug may be removed and the tab 113 pushed rearward to energize the motor 83.

As can be seen in FIG. 1, the electric motor 83 includes a motor shaft 141 extending through an appropriate opening in the plate 31 and supporting a relatively small diameter pinion 143. Supported by a rotatable axle 145 rotatably extending through a bearin g aperture 147 in the plate 31, is a relatively larger diameter coupling gear 149 having teeth 150 disposed about its outer circumference meshed with the pinion 143. As shown more cleariy in the enlarged view of FIG. 3, the coupling gear 149 includes an axial spacer projection 151 with an elongated axial bore 153 wherein the axle 145 is fixedly attached. The gear 149 may be fabricated from any suitable substance such as a nylon material, for example, and the projection 151 may be an integral part of the gear 149, which projection maintains a minimum distance between the gears and the plate 31.

The gear 149 is further provided with holes 155 symmetrically spaced about the axis 35 to accommodate and hold a similar number of projections 157 of a hollow, truncated, conically-shaped, resilient coupling member 159 (alternately the member 159 may be bonded directly to the gear 149). The projections 157 extend from the base periphery 161 of the hollow truncated conically-shaped member 159 and include relatively larger diameter retaining end portions 163 in order to hold the member 159 in position against the gear 149. The coupling member 159 is designated to be compressible axially (see FIGS. 4 and 5) and distorted laterally but still be able to effectively transmit torque between its base periphery 161 and its forward tubular axial projection 165. It has been found that a rubber or neoprene material is suitable for this application, but other materials exhibiting the desired characteristics may be used. This coupler also allows easy disassembly by simply pulling propeller and shaft out. Shaft 35 is then taken out of propeller 19 for reassembly.

An axial bore 169 is provided in the projection 165 with an inner diameter less than the diameter of the shaft 35 so that a significant frictional grip is provided by the coupling member on the propeller shaft to transmit torque thereto. The shaft 35 is rotatably supported at the housing's forward end 27 by a bearing element 171 with an axial bore 173 and which has an axially aligned bushing portion 175 and an annular disc portion 177. The bushing portion 175 has an outer diameter to slideably fit within a bore 179 in the housing 25 adjacent the front end 27 to support the shaft 35 thereat. The annular disc portion 177 is at least the spinner diameter of the propeller 19 so that the impact force is transmitted over the full area of the material.

In the embodiment illustrated in FIGS. l-S, the portion 25 includes a removable propeller shaft housing structure 181 having a relatively large diameter hollow cylindrical rear portion 183 terminate at a rear peripheral edge 185 against the plate 31, and an elongated tubular portion 187 with a ribbed, reduced-diameter forward portion 189 terminated at the end 27.

Integrally joining the rear portion 183 to the elongated tubular portion 187 is a unique hollow truncated cone portion 191 exhibiting an approximately constant force characteristic with compressible displacement. The exact nature of this force characteristic associated with a given compressible displacement is determined by the material used, the thickness of the'material in the truncated region, the smaller 193 and the larger 195 diameters of this conical structure and the cone angle. The purpose of this configuration is to provide an advantageous shock absorbing feature as an integral part of the housing structure 25. The portion 191 is in effect similar to a dish-shaped disc spring known in the mechanical art as a Belleville spring, although it is modified by its integral attachment to the cylindrical portions. Additional information concerning this type of device may be obtained by making reference to texts such as Fundamentals of Machine Design" by C. A. Normal et al., published by the MacMillan Company, New York.

The design of the portion 25 is thus directed to the preventing or lessening of damage to the power train and airframe structures and components, in the event of a severe compressive load inwardly exerted on the nose of the aircraft 11, as when the latter crashes nose first to the ground or into a wall; an event which may occur when inexperienced persons control the craft or when natural forces of sufficient magnitude overcome the natural stability of the craft in flight.

Referring now more particularly to FIGS. 4 and 5 the operation of the various structures and elements of the nose portion of the aircraft 11 to resist impact damage is illustrated. Upon initial contact with the ground, for example, the propeller l9 and its attached shaft 35 will be pushed rearwardly causing some deformation in the resilient coupling member 159, as illustrated in FIG. 4. It can be seen that the member 159 is disposed between the inwardly moving shaft 35 and the gear 149 which cannot so move because of its spacer portion 151 being in contact with the plate 31. The conical side walls of this member will thus buckle and absorb energy without transmitting excessive forces to the gear 149 or the plate 31. The resiliency of the coupling member 159 also allows the rear end of the propeller shaft 35 to move laterally without deforming the shaft when the impact force exerted on the propeller 19 includes components in directions other than along the rotational axis 33 of the shaft 35.

In the event that the force is greater than that which can be absorbed by the action of the coupling member 159, the propeller will be pushed against the disc por tion 177 of the bearing member 171, which will in turn push against the end 27 of the nose cone portion 25. This force will then be transmitted back along the rigid elongated tubular portion 187 of the truncated cone portion 191 which is fixedly anchored at its outer periphery 195 by the rigid hollow cylindrical portion 183 and the plate 31. This compressive load will cause the more inward region of the conical portion 191 to deflect relatively towards the plate 31, at first at a relatively fast pace, but at a non-linear, increasingly lesser rate. The deflection of the member 191 is shown in FIG. 5 by comparing its original position (identified by the dashed outline 191') and its final position shown by the solid outline 191". By taking into consideration the mass of the aircraft l1 and the possible maximum velocity with which it may impact the ground or another object, one skilled in the art will be able to design a shock absorbing portion 191 which will absorb the compressive energy so produced and prevent severe damage to the craft, particularly the motor, battery of cells and gear train, from excessive deceleration forces.

In order to facilitate assembly and removal of the propeller shaft housing 181, a rotating-lock attachment arrangement is provided on the plate 31 and at the peripheral edge of the housing's rear portion 183, as best illustrated in FIG. 2. This arrangement includes three speced L-shapedretaining brackets.201 on the forward face 203 of the plate 31 and three associated tabs 205 extending radially from the edge 185. To assemble these units, the tabs 205 are positioned against the plates front face 203, at one side of the brackets 201, before rotating the housing 101 and thereby moving the tabs 205 into engagement with the brackets. Also, the front face 203 of the plate may include circular segment ridges 207 which register with the inner surface 209 of the portion 183 for proper axial alignment, thereof. Additionally, a stop projection 211 may be provided adjacent one side of one of the tabs 205 to restrict the amount of such rotation so that the tabs will be centered in the holding brackets, as shown more clearly in the embodiment of FIGS. 6 and 7.

Another embodiment of the propeller shaft housing structure 181 is shown in FIGS. 6 and 7 and designated cone configuration 187' is substituted for the tubular structure 187 and the ribbed reduced diameter portion 189. Elongated ribs 213 radiate gradually as they extend back from the front end 27 to provide additional compressive rigidity and strength to the elongated portion 187.

Referring now to FIGS. 8 and 9, there is shown a second embodiment of a flyable toy aircraft 311 having a fuselage 313, a wing member 315 mounted on the fuselage 313, and a propeller 317 rotatably mounted by means of a propeller shaft 319 at the nose portion 321 of the fuselage 313. Mounted in the fuselage 313 is a power plant 323 including an electric motor 325, the output shaft 327 of which carries a pinion gear 329 meshed with and driving an output gear 331 mounted on an output shaft 333 of the gear train assembly 335. The electric motor 325 is preferably mounted directly on the gear train assemblys frame 337 which in turn is bolted or otherwise attached to a bulkhead member 339 within the fuselage structure or frame 313.

In this embodiment of the invention, the forward portion 321 of the aircrafts fuselage 313 includes a cuplike nose structure 341 slidably mounted over a fuselage cowling portion 343. Within the fuselages forward portion 321, a generally U-shaped energy absorbing member 345 is attached at its ends 347, by any suitable means such as rivets 349, to brackets 351 extending in generally a forward direction from, and as integral parts of, the bulkhead structure 339.

As can be seen in FIGS. 8 and 9, the resilient energy absorbing member 345 has relatively broad surfaced sides 353 and a generally transverse front end portion 355 wherein a; hole 357 is located. The hole 357 is aligned with'a hole 359 in the nose structure 341 in order to accept a bushing oprtion 361 inwardly extending from, and an integral part of, a thrust bearing disc portion 363 lying in a plane orthogonal to the rotational axis 365 of the propeller shaft 319. As can best be seen in FIG. '8, the propeller shaft 319 is rotatably supported in an elongated bore 366 extending through the

portions

361 and 363 comprising a front bearing member 367.

The output shaft 333 of the gear train assembly 335 is operatively coupled to the rear end 371 of the propellershaft 319 through a-movable coupling means comprising a special coupling assembly 373 which includes an elongated member 375 having an axial bore 377 dimensioned to forcibly accept, or by any other means attached to, an outer end 379 of the output shaft 333. Also, the opposite end of the member 375 is provided with a bore 381 having an axis aligned with that of the bore 377, and dimensioned to slidably accept the end 371 of the propeller shaft 319. An elongated slot 383 is milled or otherwise provided in the side 385 of the member 375 and communicates with the bore 377. Preferably, the slot 383 extends completely through the member 375 to accept a pair of arms 387 transversely extending from the shaft end portion 371. In this manner, the end portion 371 may slide axially in the bore 377, only limited by the length of the slot 383, while any rotationalmovement of the output shaft 333 is transmitted through the member 375 to the arms 387 and thus to the shaft 319 and its fixedly attached propeller 317.

In normal operation, the motor 325 is activated by conventional means and the rotational power of its shaft 327 is transferred through the reduction gear train assembly 335 to the output shaft 333 and through the special coupling assembly 373 to the shaft 319 and the propeller 317. The length of the shaft 319 is such that the arms 387 are normally positioned adjacent the forward end of the slot 383, as shown in FIGS. 8 and 9.

Impact force incident on the toy will usually occur at the propeller's spinner area 389 to cause a rearward movement thereof. This is illustrated in FIG. 10 by the position of the spinner 389 and the nose structure 341, as compared to the normal position of the spinner and structure 341 indicated by the dashed outlines 391 and 393, respectively. This movement of the spinner 389 causes it to force the bearing member 367 to push against the nose structure 341, which in turn, transfers the force to the transverse end 355 of the resilient energy absorbing member 345. The inward force impressed on the end 355 causes the energy absorbing members sides 353 to bow outwardly and thereby dissipate much of the impact energy.

As may be seen in FIG. 10, the inward movement of the spinner 389 causes no harm to the nose structure 341 or to the fuselage cowling portion 343 since the sidewall 395 of the nose structure 341 slides over the outer surface 397 of the fuselage cowling portion 343. Also, the chance of damage to the propeller shaft 319 and to the gear train assembly 335 and its driving motor 325, is significantly minimized, upon impact, because the special coupling assembly 373 allows the end por tion 371 of the propeller shaft 319 to freely move inwardly the length of the slot 383, as seen in FIG. 10.

A third embodiment of the present invention is illustrated in FIGS. 11 and 12. Here, there is shown the front portion of a flyable toy aircraft 401 constructed similarly to the previously described toy 311, except for the energy absorbing structure. In this embodiment, the energy absorbing member 353 and the nose structure 341 are replaced by a molded resilient energy absorbing nose member 402 having an opening 405 in a forward end 407 thereof. The axial bushing portion 361 of the front bearing member 367 extends through the opening 405 so that the propeller shafts rotational axis 365 is aligned with the rotational axis of the special coupling assembly 373 and the output shaft 333. An edge portion 409 of the nose member 403 registers in and is preferably bonded to an offset lip portion 41 1 at the leading edge of the fuselage cowling portion 343A.

FIG. 12 illustrates that upon impact, the propellers spinner area 389 forces the front bearing member 367 against the forward end 407 of the energy absorbing nose member 403. This action causes the nose member 402 to deform in a manner that substantially absorbs the impact energy and prevents it from being directly transferred to the fuselage of the aircraft 401. As in the case of the previously described embodiments of the invention, the inward movement of the propeller shaft 319 is not transferred to the output shaft 333 of the gear train assembly 335 due to the design of the special coupling assembly 373. Additionally, a spring 382 may be provided in bore 381 to absorb energy by being compressed when arms 387 move from the position shown in FIG. 11 to the position shown in FIG. 12. Lateral displacement of shaft 319 may be accommodated by providing a ball 333A on output shaft 333 and by drivingly connecting ball 333A to coupling assembly 373 with a pin 333B passing through ball 333A and engaging a bifurcated end 333c on coupling assembly 373.

From the foregoing, it should be evident that the present invention provides a propeller-driven toy structure that resists impact damage and constitutes a significant advancement of the propeller-driven toy art.

It should be understood that the materials used in fabricating the various components of the aircraft structure described above are not critical and any material generally considered suitable for a particular function may be utilized.

Although three embodiments of the invention have been described in detail, it should be understood that other embodiments and modifications of the invention may be constructed in accordance with the teachings of the invention as described herein. Accordingly, it is intended that the foregoing disclosure and drawings shall be considered only as illustrations of the principles of this invention.

What is claimed is:

1. In a propeller-driven toy having a body, a propeller, a power plant and power transmitting means operatively coupling said propeller to said power plant at one end of said body, improved meansfor resisting impact damage, comprising:

energy absorbing means mounted in said toy between said propeller and said power plant for absorbing impact energy incident to said one end of said body; and

movable coupling means provided on said power transmitting means for operatively coupling said propeller to said power plant through said energy absorbing means, whereby said propeller may move axially relative to said power plant when said energy absorbing means is deformed by an impact.

2. The improvement according to claim 1 wherein said energy absorbing means is a resilient member forming part of said movable coupling means.

3. The improvement according to claim 2 wherein said movable coupling means is an elongated member having an axial bore slidably receiving a propeller shaft connected to said propeller and wherein said resilient member is a spring mounted in said axial bore for receiving compressive forces from said propeller shaft.

4. The improvement according to claim 2 wherein said power transmitting means includes a propeller shaft having one end connected to said propeller and wherein said resilient member is a hollow, truncated, conically-shaped member connecting the other end of said propeller shaft to said power plant.

5. The improvement according to claim 1 wherein said energy absorbing means includes:

a propeller-shaft housing structure having an elongated nose portion with a propeller-facing end, and

having an increased-diameter portion, said elongated nose portion and said increased-diameter portion being joined by an integral truncated cone portion exhibiting an approximately constant force characteristic with compression displacement, said nose portion, increased-diameter portion and truncated cone portion being axially aligned with a common longitudinal axis.

6. The improvement according to claim 5, wherein said elongated nose portion is a hollow truncated cone.

7. The improvement according to claim 5, wherein at least the forward portion of the outer surface of said elongated nose portion includes a plurality of uniformly spaced longitudinal ribs.

8. The improvement according to claim 5, wherein said elongated nose portion includes an elongated tube portion and a reduced-diameter tube portion terminating at said propeller-facing end.

9. The improvement according to claim 5, wherein said power transmitting means includes an elongated propeller shaft rotatably disposed in said housing structure essentially along said longitudinal axis and extending beyond said propeller-facing end, and a shaftdriving gear rotatably mounted in said housing structure perpendicular to and centered along said longitudinal axis, and wherein said movable coupling means includes a resilient coupling member attached between one end of said propeller shaft and said shaft-driving gear allowing a restrained degree of axial and lateral displacement of said propeller shaft at the juncture of said propeller shaft and said coupling member.

10. The improvement according to claim 9, wherein said shaft-driving gear includes a plurality of apertures symmetrically spaced about said longitudinal axis, and wherein said resilient coupling member includes a shaft-accepting bore and a plurality of rearwardlyextending projections registering with and captured by said plurality'of apertures in said shaft-driving gear.

11. The improvement according to claim 10, wherein said resilient coupling-member includes a tubular forward portion having a shaft-accepting bore for receiving one end of said propeller shaft and relatively thinwalled, hollow, truncated-cone rear portion, said projections extending from the base edge of said truncated-cone rear portion.

12. The improvement according to claim 9, wherein said propeller is provided with an axial bore and wherein said power transmitting means includes a nose bearing member having an axial bushing portion and a transverse annular washer portion integral therewith,

the other end of said propeller shaft being seated in said axial bore of said propeller, said axial bushing portion of said nosebearing member being disposed in the axial opening in said propeller-facing end of said 'nose portion, and said annular transverse washer portion being disposed between said propeller and said propellerfacing end of said nose portion.

13. The improvement according to claim 1, wherein said power transmitting means includes a power output shaft on said power plant and an elongated propeller shaft attached at a forward end to said propeller, said propeller shaft lying essentially in line with the axis of rotation of said power output shaft, said movable coupling means being fixedly attached to and between a rear end of said propeller shaft and said power output shaft for rotating said propeller shaft with rotation of said 'power output shaft while allowing relative axial movement between said shafts.

14. The improvement according to claim 13, wherein said movable coupling means includes an elongated member having an elongated bore therein dimensioned to slidably accept one of said shafts therein, said elongated member also including a second bore axially aligned with said elongated bore and in which the other of said shafts is fixedly held, said elongated member further including at least one elongated slot in its outer surface communicating and axially aligned with said elongated bore, said movable coupling means also including guide means fixedly associated with one of said rubber material.

18. The improvement according to claim 15, wherein said resilient member is a generally U-shaped band of metal attached at its end at opposite sides of said body.

19. The improvement according to claim I8, wherein said body is an airplane fuselage and wherein said band lies within the cowling portion of the said fuselage.

20. The improvement according to claim 19, wherein said cowling includes an inwardly slidable nose portion overlapping a fuselage portion.

a: a a k

Claims

1. In a propeller-driven toy having a body, a propeller, a power plant and power transmitting means operatively coupling said propeller to said power plant at one end of said body, improved means for resisting impact damage, comprising: energy absorbing means mounted in said toy between said propeller and said power plant for absorbing impact energy incident to said one end of said body; and movable coupling means provided on said power transmitting means for operatively coupling said propeller to said power plant through said energy absorbing means, whereby said propeller may move axially relative to said power plant when said energy absorbing means is deformed by an impact.

5. The improvement according to claim 1 wherein said energy absorbing means includes: a propeller-shaft housing structure having an elongated nose portion with a propeller-facing end, and having an increased-diameter portion, said elongated nose portion and said increased-diameter portion being joined by an integral truncated cone portion exhibiting an approximately constant force characteristic with compression displacement, said nose portion, increased-diameter portion and truncated cone portion being axially aligned with a common longitudinal axis.

9. The improvement according to claim 5, wherein said power transmitting means includes an elongated propeller shaft rotatably disposed in said housing structure essentially along said longitudinal axis and extending beyond said propeller-facing end, and a shaft-driving gear rotatably mounted in said housing structure perpendicular to and centered along said longitudinal axis, and wherein said movable coupling means includes a resilient coupling member attached between one end of said propeller shaft and said shaft-driving gear allowing a restrained degree of axial and lateral displacement of said propeller shaft at the juncture of said propeller shaft and said coupling member.

10. The improvement according to claim 9, wherein said shaft-driving gear includes a plurality of apertures symmetrically spaced about said longitudinal axis, and wherein said resilient coupling member includes a shaft-accepting bore and a plurality of rearwardly-extending projections registering with and captured by said plurality of apertures in said shaft-driving gear.

11. The improvement according to claim 10, wherein said resilient coupling member includes a tubular forward portion having a shaft-accepting bore for receiving one end of said propeller shaft and relatively thin-walled, hollow, truncated-cone rear portion, said projections extending from the base edge of said truncated-cone rear portion.

12. The improvement according to claim 9, wherein said propeller is provided with an axial bore and wherein said power transmitting means includes a nose bearing member having an axial bushing portion and a transverse annular washer portion integral therewith, the other end of said propeller shaft being seated in said axial bore of said propeller, said axial bushing portion of said nose bearing member being disposed in the axial opening in said propeller-facing end of said nose portion, and said annular transverse washer portion being disposed between said propeller and said propeller-facing end of said nose portion.

13. The improvement according to claim 1, wherein said power transmitting means includes a power output shaft on said power plant and an elongated propeller shaft attached at a forward end to said propeller, said propeller shaft lying essentially in line with the axis of rotation of said power output shaft, said movable coupling means being fixedly attached to and between a rear end of said propeller shaft and said power output shaft for rotating said propeller shaft with rotation of said power output shaft while allowing relative axial movement between said shafts.

14. The improvement according to claim 13, wherein said movable coupling means includes an elongated member having an elongated bore therein dimensioned to slidably accept one of said shafts therein, said elongated member also including a second bore axially aligned with said elongated bore and in which the other of said shafts is fixedly held, said elongated member further including at least one elongated slot in its outer surface communicating and axially aligned with said elongated bore, said movable coupling means also including guide means fixedly associated with one of said shafts and slidably positioned and captured in said elongated slot.

15. The improvement according to claim 1, wherein said energy absorbing means includes a resilient member attached to said body, a portion of said resilient member lying immediately behind said propeller.

16. The improvement according to claim 15, wherein said resilient member forms a portion of the cowling at the front of said body.

17. The improvement according to claim 15, wherein said resilient member is fabricated from a synthetic rubber material.

19. The improvement according to claim 18, wherein said body is an airplane fuselage and wherein said band lies wIthin the cowling portion of the said fuselage.