US 2993297 A
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Description (OCR text may contain errors)
y 1961 w. A. BEDNAR EI'AL 2,993,297
TOY ROCKET Filed Aug. 19, 1959 WILLIAM A. BEDNAR ROBERT D. CRAWFORD MM W 2 7 ATTORNEYS INVENTORS United States Patent O 2,993,297 TOY ROCKET William A. Bednar and Robert 1). Crawford, Cuyahoga Falls, Ohio, assignors to Research Unlimited, Inc., Cuyahoga Falls, Ohio, a corporation of Ohio Filed Aug. 19, 1959, Ser. No. 834,895 '1 Claim. (Cl.4674) This invention relates to an improved toy rocket which is launched by the impact of a sudden pressure pulse of compressed air.
The improved toy has an aeronautically balanced missile projectile, cylindrical in shape, which is open and is provided with tail fins at its rear end and has an impact plug and nose cone, advantageously of yieldable material, such as sponge rubber, at its forward end.
The launching apparatus for the missile has a launching tube over which the missile fits with a close fit, and of a length such that itcan be held and aimed by the hand of the operator with the missile in place on it. The
launching apparatus for the missile also has an impact bulb of tough, flexible material adapted to withstand a substantially instantaneous impact by the foot of the operator. Connecting this impact bulb with the launching tube is a flexible tube of suflicient stiffness and strength to withstand a sudden pressure pulse of compressed air without deforming.
The launching apparatus is intended to be used by placing the impact bulb on the ground, by holding the launching tube in the hand, and subjecting the bulb to a sudden impact to flatten it and generate the pressure pulse which launches the missile.
The size and construction of the launching tube, impact bulb, and connecting tubing are such that when the impact bulb is subjected to substantially instantaneous compression by impact by the foot of the operator, a sudden pressure pulse of compressed air is generated, and this pulse is transmitted through the flexible tube and launching tube to the missile to blast it from its launching tube at high velocity.
The invention will be further illustrated and described in connection with the accompanying drawing, which shows an advantageous embodiment thereof. In the accompanying drawings,
FIG. 1 shows a child holding the launching tube of the missile in his hands and with his foot ready to stomp on the bulb to launch the missile;
FIG. 2 is an enlarged view with parts cut away, showing the missile, the launching tube and the upper end of the flexible tube;
FIG. 3 shows a suitable type of impact bulb connected to the lower end of the flexible tube, and with parts broken away; and
FIG. 4 is a view taken on the line 44 of FIG. 2.
In the drawings, the missile 1 is shown as mounted on the launching tube 2, which is connected to the flexible tube 3 through an overlapping portion indicated at 4, the parts being suitably cemented together. The lower end 5 of the flexible tube 3 is connected with the impact bulb '6.
The rocket 1 is cylindrical in shape and is made of light, stiff material such as kraft paper spirally wound and glued together with a suitable resin glue to give a thin, still, cylindrical tube of e.g. 0.025 inch wall thickness. At its upper end, the missile 7 has a plug 8 of plastic material secured thereto as an impact element, and above this is the nose cone 9 which is advantageously of yieldable material such as sponge rubber. At its other end, the missile 1 has tail fins 10 carried by a thin, cylindrical member .11 secured to the lower end of the cylinder 7 and advantageously made of plastic mate- The missile is aerouautically balanced, this balance being effected by the weight of the plug 8 and the nose cone 9 which causes the rocket to be balanced at about one-third the distance from its front end. 7
The plug 8 is an impact plug near the front end of the missile, to which the energy of the sudden pressure pulse of compressed air is transmitted to launch the missile. The application of the pulse at the forward part of the missile makes it particularly effective. I
The launching tube 2 is a rigid tube of plastic material, e.g., polystyrene resin, of a wall thickness of about V inch and an inside diameter of about inch. The size of the launch-ing tube and of the missile is such that the missile can be readily applied to and removed from the launching tube. The tolerance between the launching tube and the missile may thus be, e.g., .006 inch.
The tubing 3 is a flexible tubing of suflicient stifiness a'nd'strength so that it is not compressed by-the hand of the operator and is not deformable under the pressure 'pulse of compressed air by which the missile is launched.
The tube may thus be a vinyl resin tubing of about of an inch to /2 inch in inside diameter. It is shown as a tube with an outside diameter of of an inch, which fits closely within the launching tube 2, and with an inside diameter of of an inch. In length, this flexible tubing will be sufiiciently long to enable the impact bulb to rest on the floor while the launching tube is held in the hand of the operator.
The impact bulb 6 is made of thin, resilient, plastic material which will withstand repeated impact and which, when subjected to impact, will flatten on the ground to eflect substantially instantaneous expulsion of the air therefrom into the. flexible tubing as a pressure pulse which travels rapidly and almost instantly to the launching tube to fire the missile. The bulb 6 may thus be made of rubber, such as latex rubber, which is formed into the shape of the bulb, e.g., by compound rotation about axes at difierent angles in a water-absorbent mold, followed by drying and curing of the bulb. The bulb shown is about of an inch in wall thickness and of a capacity of about 500 cubic centimeters. Stifiening ribs 13, 14 and 15 are provided. The bulb should be one that can not only be compressed substantially instantaneously by impact, but which is resilient and which will return to its normal size and shape when the pressure is released.
With a bulb of 500 cubic centimeters capacity and with the flexible tubing and launching tube having a volume of about cubic centimeters, a sudden impact on the bulb, which will flatten it in about 12 milliseconds, will create a sudden pressure pulse of compressed air which travel to the impact plug of the missile and launch the missile at a rate e.g., such that only about 4 milliseconds are required from the time the missile starts to move until it is free from the end of the launching tube.
Pressures have been measured at the side of the launching tube near its upper end as high as 37 pounds per square inch, and a number of readings were made with an average of 26 pounds per square inch. But it is not the sudden pressure pulse alone which launches the missile. The rocket, when it leaves the launching tube, is essentially pressurized and, as it leaves the launching tube, the air escapes, giving the missile an additional boost.
In the use of the missile and launching apparatus, the impact bulb is placed on the ground and the launching tube, with the missile on it, is held in the hand, so that it can be aimed for the desired trajectory or target. By a quick stomp with the foot on the impact bulb, the missile is blasted oil from the launching tube.
FIG. 1 shows a child holding the missile and ready a a u to launch it. The launching tube can be held by one child and the impact bulb operated by another. One child can thus stomp or jump on the impact bulb, while the launching tube is held by another. While the toy rocket is of special interest to children, it is also of interest to adults. Tests made with the missile by a sixty percentile man wearing heavy field boots and stomping on the impact tube to cause flattening of the bulb in about 12 milliseconds, have resulted in flights of the missile for distances of up to and more than 300 feet horizontally when shot at an angle of around 47 from the horizontal, and a vertical distance of up to around 130 feet and with an average of a number of flights of around 110 feet. a
The impact bulbs are made of material which will withstand the impacts without injuring the bulbs. Up to 7000 impacts. have thus been applied to one of the bulbs without interfering with its operation.
We claim: 3
A toy rocket having a thin, stifi, hollow, cylindrical missile project with directional tail fins, a nose cone of yieldable material and an impact plug in the forward end of the missile adjacent the nose cone, and launching means for said projectile including a rigid, hollow, cylindrical launching tube for holding the projectile before launching and directing it when fired, said tube being 4 insertable into said cylindrical missile projectile and when inserted therein having a close sliding fit therewith, a flexible hose of substantially noncompressible and substantially nonexpandable material connected to said launching tube, and an impact bulb of tough, flexible material adapted to withstand "a sudden impact by the foot of the operator, said bulb being secured to one end of said flexible tube and having a volume substantially greater than the combined volume of said launching tube and said hose, and the length of the flexible tubing being such that when the bulb is on the ground, the launching tube can be held in the hand of the operator standing in upright position, the construction and arrangement being such that, when the bulb is flattened as 'by a sudden impact of the operators foot thereon, a resulting sudden pressure pulse of compressed air is transmitted through said hose and launching tu beto the missile to launch it.
References Cited in the file of this patent UNITED STATES PATENTS 2,836,008 7 Nichols May 27, 1958 FOREIGN PATENTS 446,391 Germany June 30, 1927 1,033,929 France Apr. 8, 1953