US 3537208 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
K. B. MARTIN TOY AIRPLANE 2 Sheets-Sheet v1 Filed April 18, 1968 N y 5 H U W 5 K 2 4 ATTOEA/'S E United States Patent 3,537,208 TOY AIRPLANE Kenneth B. Martin, 1321 N. th Ave., Upland, Calif. 91786 Filed Apr. 18, 1968, Ser. No. 722,467 Int. Cl. A63h 27/12 US. Cl. 46-75 3 Claims ABSTRACT OF THE DISCLOSURE A toy airplane of the type that is powered along a circular path by being swung at the end of a cord or tether, includes a dynamic stabilizer, inertia powered propeller, and engine noise simulator. The propeller, driven by the air as the plane moves along its path, rotates a flywheel to effect gyroscopic stabilization, simultaneously drive the engine sound simulator, and provide inertia power during the landing glide and subsequent roll-out along the ground.
The present invention pertains generally to a toy airplane, and, more particularly, to a plane for being propelled through the air at the end of a tether with special stabilization, propulsion assisting and noise making apparatus whereby the plane is provided with the sound, feel and operation highly approximating that of selfpropelled toy planes.
BACKGROUND OF THE INVENTION A very popular present day toy airplane is one powered by a miniature gasoline engine and controlled via a pair of wires attached to the plane, the other ends of which are manipulated by the operator, although such toy planes are highly realistic and simulate flight of full size airplanes quite closely, controlled flight requires a certain amount of skill on the part of the operator, and, for this reason, younger children are usually unable to handle them successfully. On the other hand, previously known toy planes of the non-self-powered kind have lacked the appearance, sound or feel of powered flight. Moreover, these prior art planes have not had propulsion, consequently they lack the normal landing and roll-out characteristics, and, therefore, have not been completely satisfactory.
It is, therefore, a first object of the present invention to provide a toy airplane of the non-engine-powered kind, having improved characteristics simulating powered flight and propulsion assisted landing and roll-out.
A further object is the provision of a toy airplane as described in the preceding object that is stabilized during flight to maintain on-course bearing.
A still further object is the provision of a non-enginepowered toy airplane with engine noise simulation and flight stabilization apparatus powered by propeller rotation.
A still further object is to provide inertia powered propulsion for a toy airplane during the landing glide and subsequent roll-out along the ground.
Yet another object is the provision of a toy airplane as in the above objects having improved, inexpensive, lowfriction bearing means associated with the stabilization and noise simulation apparatus.
Other objects and advantages will be apparent to those skilled in the art on reference to the following description when considered in the light of the accompanying drawmg.
DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a toy airplane constructed in accordance with this invention in the normal mode of use.
FIG. 2 is an elevational, partially sectional and frag- "ice mentary view of the plane nose portion showing the inertial propulsion, flight stabilizing and engine noise simulation apparatus of the invention.
FIG. 3 is a sectional view taken along the line 3-3 of FIG. 2.
FIG. 4 is an enlarged view of the stabilizing and engine noise simulation apparatus depicting the technique of engine noise simulation generation of the present invention.
FIG. 5 is a plan view of the bearing and support means for the stabilizing and engine noise simulator shown in blank form.
FIG. 6 depicts the bearing and support means of FIG. 5 fully formed.
FIG. 7 is an elevational, partially sectional, view of a toy airplane showing the use of two sets of inertial propulsion, stabilizing and engine sound simulation apparatus, one in the conventional front or pull position, and the other in pusher position.
DESCRIPTION OF A PREFERRED EMBODIMENT With reference now particularly to FIG. 1, a toy airplane 10 is provided with motive power via a tether or cord 11 which is swung by an operator 12 in a generally circular path about the operator as a center. In a way that will be more explicitly set forth later herein, flight of the plane along its circular path rotates the propeller 13 to drive the stabilizing and engine sound simulator indicated generally at 14, as well as provide inertial propulsion during landing glide and roll-out. Accordingly, the plane not only sounds as if it is engine-powered, but through the stabilization effected, the plane handles well during steady flight, and during landing is provided with auxiliary driving power.
Turning now to FIG. 2, the propeller 13 is affixed onto the anterior end of a shaft 15 that passes through appropriately dimensioned openings in first and second bearing supports 16 and 17, respectively. The posterior end of the shaft is formed generally to a point as at 18 for thiguitgngly engaging an upstanding bearing plate or g1 Intermediate the bearing support 17 and gib 19, the shaft 15 carries an axially mounted, cylindrical flywheel 20 for rotation therewith. On the forward side of the flywheel 20 a conical portion 21 extends along the shaft toward the bearing support 17 for engaging the same at the forward limit of shaft displacement. The flywheel is so dimensioned that the shaft has a relatively large amount of longitudinal playthe conical portion 21 contacting the bearing support at one limit, and the pointed end 18 thrusting against gib 19 at the other limit. It is important to note that when 18 bears against plate 19, the propeller 13 does not contact the first support bearing 16 or adjacent parts of the plane, since this would induce undesirable friction drag on shaft rotation with consequent poor overall performance.
It is important that the flywheel 20 be of such construction and so mounted on the shaft that it is symmetrical about the shaft. In this manner rotation of the flywheel with the shaft produces a gyroscopic stabilization of the plane causing it to tend to adhere to its flight course as if self-powered, rather than wobble or otherwise be easily deflected from its course by relatively slight changes in rotational velocity, or changes in tension of the tether when letting it out or taking it in. It is this gyroscopic effect of the rotation of the flywheel 20 that gives the plane the feel of powered flight and makes it handle well.
In addition to the longitudinal end play of the shaft already alluded to, the openings in the support bearings 16 and 17 through which the shaft passes are made slightly oversize. As a result of this construction, on rotation of the shaft, a noisesimulating an engine'sound is'created by the shaft vibrating or hammering against the wall surfaces of the bearing supports defining the openings. This action is shown in FIG. 4, where the dashed line depictions illustrate the two extremes of shaft vibration about a central position shown in solid line.
A further important and advantageous aspect of the invention is the shaft mounting. When the single-propeller version of FIGS. 1 and 2 is in flight, the propeller 13 is forced by wind pressure to its rear-wardmost position, bringing the shaft point 18 into a thrust bearing relationship with the plate 19. In this phase of operation the bearing supoprts 16 and 17 provide but a very slight amount of frictional drag on the shaft, and it, therefore, rotates freely. On the other hand, when decelerating the plane, as in the case of landing, the conical portion 21 contacts the bearing support 17 forming a low friction thrust bearing, with the walls of the openings in 16 and 17 contributing only a very small frictional drag on the shaft. By this low friction mounting of the shaft, relatively high speed rotation of the propeller and flywheel for swinging rotation of the plane is assured, thereby promoting good stabilization of the plane even at low air speeds. When the airplane is in flight around the operator and the operator decreases the speed of the ariplane to cause it to glide toward the ground and land, the propeller exerts a pulling force as in a normal engine-powered airplane by reason of momentum of the flywheel turning the propeller at substantially constant speed. When the propeller 13 in FIG. 2 exerts a pulling force, bearing 21 comes in contact with hearing support 17 and the pulling force is thereby transmitted to the airplane flame. Also, this pulling force is continued during roll-out, dampening the tendency of the plane to bounce upon ground contact.
Constructional details of the shaft bearing and support assembly are shown best in FIGS. and '6. Fabrication can be made from a single flat blank (FIG. 5 with hear ing supports 16 and 17 and included openings, formed in one stamping operation. Downwardly bent ears 22 for being secured to a wall of the plane fuselage (-FIG. 3) can also be simultaneously formed with supports 16, 17. In assembling the various parts to one another, the shaft carrying the flywheel is passed through the openings in supports 17 and 16, in that order, with the shaft terminus suitably secured to the propeller. The plate 19 is then formed into its upstanding position. The finalstep is the mounting of the entire shaft, propeller and bearing support assembly into an appropriately formed cavity within the plane fuselage.
FIG. 7 shows the application of the present invention to a different style of aircraft in which there are provided a forwardly directed propeller 24 and a pusher propeller 25 that is rearwardly directed. The propellers are connected to respective stabilizing and engine noise simulating apparatus 26 and 27, identical to that described in connection with the first described embodiment.
Although only two specific embodiments of the present invention have been described and illustrated herein, many changes and modifications will, of course, suggest themselves to thoseskilledin the art. These embodiments have been selected for this disclosure for the purposes of illustration only.
What is claimed is: 1. A toy airplane for being swung at the end of a tether and having a freely rotating propeller, comprising:
a shaft having one end affixed to the propeller and extending into a cavity within the airplane fuselage; bearing means supporting the shaft for rotation, said bearing means including oversize openings receiving the shaft, whereby on rotation of the propeller the shaft vibrates against walls defining said openings thereby simulating the sound of an airplane engine; and a mass aflixed to the shaft within the cavity and symmetrically disposed about the shaft as an axis, whereby on rotation of the propeller and shaft, the mass is caused to rotate producing gyroscopic action which stabilizes flight of the airplane. 2. A toy airplane for being swung at the end of a tether and having a freely rotating propeller, comprising:
a shaft having one end aflixed to the propeller and extending into a cavity within the airplane fuselage; bearing means supporing the shaft for rotation, including a thrust bearing associated with the end of the shaft; and a mass aflixed to the shaft within the cavity and symmetrically disposed about the shaft as anaxis, whereby on rotation of the propeller and shaft the mass is caused to rotate producing gyroscopic action which stabilizes flight of the airplane; said mass being aflixed to the shaft adjacent the thrust bearings, and the bearing means further including means' supporting the shaft at a point spaced from said mass at the other side of said mass, whereby the shaft is translatable longitudinally from a first extreme with the shaft end engaging the thrust bearing to a second extreme with the mass engaging the means supporting the shaft. I 3. A toyairplane-as in claim 2, in which the mass is generally cylindrical in shape and mounted axially on the shaft, said mass furtherincludingconical means integral therewith extendingalong the shaft toward the shaft supporting means for contacting the same when the shaft 1s at its forwardmost position.
References Cited UNITED STATES PATENTS 2,486,852 11/1949 Johnson 46-78 4,565,437 12/1925 Greife 48-81 XR 2,035,629 3/1936 Wing 46-76 2,747,326 5/1956 Doyle 46-50 ROBERT PESHOCK, Primary Examiner US. Cl. X.R.