US2918751A

US2918751A - Reaction propulsion toy

Info

Publication number: US2918751A
Application number: US696408A
Authority: US
Inventors: Robert J Johnson
Original assignee: SCIENT PRODUCTS Co
Current assignee: SCIENT PRODUCTS Co; SCIENTIFIC PRODUCTS Co
Priority date: 1957-11-14
Filing date: 1957-11-14
Publication date: 1959-12-29
Anticipated expiration: 1976-12-29
Also published as: GB866032A; FR1205041A

Description

Dec 29, 19.59, I R. .1. JOHNSON 5 REACTION PROPULSION TOY Filed Nov;- 14, 1957 4 Sheets-Sheet 1 v INVENTOR ROBERT J Jam sow ATTORNEY Dec. 29; 1959 R. J. JOHNSON 2,918,751

7 REACTION PROPULSION TOY F iled Nov. 14, 1957 a '4 Sheets-Sheet 2 INVENTOR ROBE RT J. JOHNSON AT O v R. J. JOHNSON REACTION PROPULSION TOY Dec. 29, 1959 Filed Nov. 14, 1957 4 Sheets-Sheet 3 INVENTOR ROBERT J. JOHNSON 29, 1959 R. J. JOHNSON 2,913,751

' REACTION PROPULSION TOY Filed Nov. 14,1957 I 4 SheetS -Sheet 4 III/I/I/I INVENTOR ROBERT J JOHNSON ATTORNEY United States Patent REACTION PROPULSION TOY Robert J. Johnson, Richmond, Va.,,assignor, by mesne assignments, to Scientific Products Company, Rich,- mond, Va., a corporation ofvirginia Application November 14, 195,.7,,Serial: No. 696,

5. Claims. (CI; 46- 4).

This invention relates to a reactionpropulsion toyv and more, particularly to a new and: improved reaction propelled toy rocket and launching devicetherefor.

It is a particular object of this; invention to provide a, toy reaction propulsion rocket. which simulates in appearance, operation and flight: an: actual ballistic missile without the inherent complexity. of such devices.

It; is afurther object of the. invention to provide such adevice wherein thev reaction. propulsion engine thereof is of. the. cold discharge type thereby providing a safe amusement and educational device for children ,Itis a further object ofthepresent invention to provide such a toy that is relatively simple in construction and operation, that may be reused for plural flights by merely recharging the reaction. engine. and wherein the angleof flight and distanceof operation may be varied within wide latitudes. i

It is a further object to provide a novel reactionengine for atoy rocket wherein the internal pressures developed within the device are effectively; maintained within the pressure limits of the constructionmaterial.

A further object is to develop. Such a device wherein the period of time required to develop operating pressures; within the rocket is relatively. short.

These and other objects and advantages are provided by a;toy--r ocket which generally comprises an elongate hollow bodyportion having a closed forward end and an open,rear wa rd end, a reaction motor. releasablymounted in the; rearward end of the, body portion, said motor including a ring having a Venturi. passage extending therethrough, a; basket releasably; secured. to the inner end of the reaction motor ring; said basket being provided with a plurality of slots extending throughv the side walls thereof, and launching means forthe toy rocket including a peg, one end, of said peg adapted to snugly engage the Venturi passage, in said reaction. motor, and latch means releasably holding the peg within the Ven-v turi passage.

The-novel features of the present'iinvetion will be more apparent to those skilledin theart from the following detailed description of the invention inreferenceto the accompanying drawings; wherein:

Fig. 1 is an elevational view of the improved reaction propulsion toy of; the invention; including its launching platform;

Fig. 2a isan exploded view in, partial; section; of: the. missile and its motor components;

Fig. 2b is an exploded view-of a-portion of the launching mechanism for; the missile shown in Fig. 1;

Fig. 3 is a longitudinal sectional;v view through the,

missile and its; motor components;

Fig. 4 is; an enlarged fragmentary: sectional view through the assembled missile and: launching platform therefor;

Fig. 5 is a section substantiallyon line-5-5 of Fig. 4;-

Fig. 6 i813. section substantially on line-6"6' of Fig. 3

1 Figa'his a-section-substantiallyonlinefl-l ofFig. 3;-

p 2,918,751 Patented; Dec. 29,. 1959 ice Referring to the drawings the illustrated embodiment of'the invention generally comprises a reaction propulsion rocket 10 which includes a body portion 12 having a reaction motor releasably secured therein and generally designated 14, rocket release mechanism 16 and launching structure 18. Each of these elements of the structure of the invention will be separately described hereinafter.

The body portion 12 of the rocket includes an elongated shell 20 having an open rear end 22, and an 'inwardly tapered forward portion 24 carrying a resilient nose piece 26. As more clearly shown in Fig. 3 of 'the drawings, the nose piece 26 is secured to the forward end 24 of the shell of the rocket by a pin 28 secured in a bore in the nose. The pin 28 includes a forwardly projecting boss 30 which snaps into a recess 32 in the resilient nose piece 26;'

At the rearward end of the body-portion 20 the rocket is provided with a plurality of stabilizing fins 34 which may be formed as an integral part of the shell 20-or bonded thereto by welding, cementing or the like. small toy rockets necessitating the employment of thin lightweight stabilizing fins 34, the fins may be provided with suitable ribsgenerally designated 36, preferably extending parallel tothe direction of flight of the rocket to reduce the tendency of the fins to bend in flightwhich would reduce the accuracy of the flight of the toy.

In the preferred formof the invention, the body 20 and the fins 34, including the ribs 36, are cast of a tough plastic such as nylon or cellulose derivatives. Particularly satisfactory results have been obtained by using cellulose acetate-butyrate.

The rear end of the body of the rocket is provided with an adapter ring 38 having a shoulder 40 adapted to abut the peripheral edge of the rocket. The internal surface of the adapter ring 38 is conveniently provided with partial threads 42 adapted to mate with cooperating partial threads 44 carried on the external surface of the nozzle portion 46 of the motor 14.

The nozzle portion 46 of motor 14; as more clearly shown in Figs. 2a, 3 and 4, includes an outlet which communicates with a constricted opening 52 which, in turn, communicates with the interior of the rocket through bore 54. The bore 54, the constriction 52; the bore 50 and the outlet 48 cooperate to define a Venturi' passage through which the fuel maintained under pressure in the body of the rocketissues during the flight of the rocket as to be more fully described'hereinafter.

The external cylindrical. surface of the nozzle 46 is provide with a shoulder 56'. which abuts the extended edge of the motor retainer ring 38 when the cooperating threads 42 and 44 are fully engaged as shown in Figs. 3 and 4. The external surface of the nozzleis also provided with a peripheral groove 58* adapted to receive a conventional resilient O ring 60 which maintains. a fluid type seal betweenthe inner surface of the motor retainer ring 38 and the external surface of the nozzle 46 when the motor is in place in the rocket body. A further groove 62 is provided adjacent the most forward? portion of the nozzle 46 which groove is adapted to receive a basket 64; provided with inwardly projecting elements 66 which snap into the groove 62 to maintain the basket 64 in axial extension from the nozzle 46' as more clearly shown in Fig. 4.

The basket 64 is adapted to receive the fuel or a; portion thereof for pressurizing; the rocket and is generally cylindrical in form and is provided with a plu-.

rality of longitudinally extending slots 68 which permit; communication between the interior of the basket and --2,91s,751 p p the interior of the rocket. The lower end of the basket 64 is also provided with a plurality of openings 70 of substantially larger size than the longitudinally extending slots 68 hereinbefore described.

The basket 64 and they-nozzle 46 may also be conveniently molded from plastic, and very satisfactory results have. been obtained by molding the. parts. from cellulose acetate-butyrate.

The releasemechanism 16- for the rocket, asmore clearly shown in -Figs. 2b and 4, comprises a cylindrical standard or peg having'a reduced cylindrical end portion 72 of a diameter slightly less than the bore 50 in the nozzle. Forwardly of the portion 72 of. the standard is provided a peripheral groove 74 adapted to receive resilient ring 76, Fig. 4, which provides a fluid tight seal'between the outer surface of the standard 72 and the inner surface of the bore50 of the nozzle.

Forwardly of the peripheral groove 74 is a further reduced extended end portion 78 having a diameter which snugly fits into the bore 52 of the constricted portion of the rocket nozzle. The standard 16 is also provided with a pair of radial bosses 80 which cooperate with a pair of bosses 82 projecting inwardly of the outlet ring 48 of the nozzle. The radial extension of the cooperating

bosses

80 and 82 are such that when the reduced end portions 72 and 78 of the standard 16 are inserted into the

bores

50 and 52 of the nozzle as shown in Fig. 4 the cooperating

bosses

80 and 82 limit the extent of roation of the standard 16 within the bores of the nozzle whereby the motor may be screwed into and out of the motor retainer ring 38 by turning the standard 16.

The standard 16 is also provided with an upstanding boss generally designated 84 which receives a latch pin 86. The latch pin 86 is mounted between the flanges 88 of the boss 84 by a pivot pin 90. The extended end of the latch pin 86 is provided with a cutout portion 92 adapted to be received about a flange 94 on the nozzle outlet 48. The other extended end of the latch 86 is bored to receive a release cord 96 which passes through a bore 98 in the standard 16. To complete the latch pin assembly a spring 100 is positioned between the flanges 88 of the boss 84 to urge the pivotally mounted latch pin 86 into latched engagement with the motor outlet nozzle ring 94.

In the illustrated embodiment of the present invention the spring 100 for urging the latch member into engagement with the extended end of the rocket motor is of the leaf-type spring. However, coil springs or other suitable means for biasing the latch member may be employed without departing from the present invention.

The rearwardmost end of the standard 16 is reduced in cross-sectional area and preferably quadrangular in shape. The quadrangularly shaped end is adapted to be freely insertable in a corresponding quadrangular opening 104 in the rocket standard launching socket 106. As more clearly shown in Fig. 2b and Fig. 9, the quadrangular opening 104 in the socket 106 is provided with one or more axially extending grooves 108 which grooves provide weep holes for liquid or air within the passage 104 to permit the free insertion thereinto of the end portion 102 of the peg 16.

The lowermost end of the standard socket 106 is bored as at 110 to receive a pivot pin 112 whereby the standard socket 106 is pivotally mounted to the launching platform base member 114 between the upstanding flanges 116 carried thereby. The lowermost end of the standard socket 106 and the upstanding flanges 116 are provided with cooperating

bosses

118, 120, 122 and 124 whereby the pivotal movement of the standard socket 106 upon the base member 114 is limited to a range of from about 90 to about 45 from horiozntal.

The base member 114 of the launching platform 18 is further provided with an axial bore 126 adapted to receive a pin 128 freely passed through the bore 126 4 and into the ground which aids in maintaining the launch-- ing.platform.114. and .its rocket mechanism in rocket launching position. The entire platform and its rocket also may be conveniently rotated about the pin 128 to vary the heading of the rocket.

The fuel for the rocket comprises a suitable acid preferably in the solid granular form, a gas generating compound and water. Very satisfactory results are obtainable with a fuel charge of citric or tartaric acid, a bicarbonate snchas sodium bicarbonate and water. In operation of the rocket, the rocket is disassembled as shown in Fig. 2a of the illustrated embodiments of the invention. The basket 64 is then filled with a bicarbonate and an acid in granular form. Very satisfactory results are obtained when the basket is filled with 3 cc. of sodium-bicarbonate and 2.5 cc. of citric acid. The acid and bicarbonate charge is in the granular form with the size of the grains usually less than the width of the slots 68 in 'the basket adapted to receive the combined citric acid sodium bicarbonate charge of 5.5 cc. It will be appreciated that with a slot width of .04 inch and with the grain size of the acid-bicarbonate charge smaller than .04 inch that the charge would not normally remainin the basket. In order to contain the granulancharge within the basket upon initial operation of the rocket the internal surface of the basket is wetted. When the dry citric acid and sodium bicarbonate is placed in the basket having its inner surface wetted the dry powders or grains form bridges across the slots preventing the remainder of the charge from passing through the slots.

The body of the rocket 12 is then filledwith from aboutfiZS to about 30 cc. of water where the rocket is about 7 inches inlength and has a maximum internal diameter of about 1 inch and a total internal volume of about 75 cc.

"the charged basket 64 is then snapped on to the nozzle mounting ring 62, the release mechanism 16 is assembled to the motor as shown, for example in Fig. 4, with the latchbar 86 in engagement with the latch ring of the nozzle. The basket, nozzle and release mechanism is then assembled to the rocket body 12 so that the cooperating parted threads 42 and 44 are fully engaged and the shoulder 56 of the nozzle is in abutting relation to the peripheral edge 38 of the motor mount 22.

The rocket is then inverted and the lowermost end 102 of the release mechanism 16 is inserted into the slot 104 of the standard socket106. As soon as the rocket Y assembly is inverted the water placed within the housing of the rocket. comes in contact with the acid-bicarbonate charge within the basket. The substantial width of the plural slots 68 in the basket and the large openings 58 at the lowermost end of the basket permit very rapid reaction between the dry sodium bicarbonate and citric acid. v

It has been found that with a rocket constructed as hereinabove described, the charge generates a pressure of about pounds per square inch within the shell of the rocket in about 1 minute where the temperature of within the rocket body acting upon the surface 134 of the forward end of release mechanism 16 forces the rocket off'therelease mechanism and the carbon dioxide and water contained within the body of the rocket are forced through the reaction engine creating thrust which sends the rocket soaring into the air.

It has been discovered that with a rocket constructed as detailed in the above example containing from about 25 to about 30 cc. of water; having a fuel charge of about 3; cc. of sodiurn bicarbonate and 2.5 cc. of anhydrous citric acid and with the rocket positioned at an angle of from about 55 to about 60 to the horizontal a rocket flight of about 150 feet will result. It has also been determined that in such a flight the rocket will travel at a maximum speed of from about 40 to 50 miles per hour.

From the foregoing description of this invention, it will be appreciated that the size and exact configuration of the rocket may be variously modified and that as the weight and size of the rocket is increased proportionate increases in the sodium bicarbonate-acid charge would be necessary in order to properly propel the device. Further, the amount of charge to be added to the basket may conveniently be in weight quantities. For example, if the total volume of the basket 64 is about 5.5 cc., the weight of sodium bicarbonate would be 2.5 grams and the weight of anhydrous citric acid would be 2.2 grams.

While enlarging or decreasing the overall size of the rocket and its motor will require larger or smaller quantities of bicarbonate-acid charge, the slot width 68 in the basket should be maintained substantially constant to insure adequate bridging during the initial operation of the device and also a rapid reaction to provide maximum pressure within the body of the missile in a relatively short period of time.

Where shorter reaction periods are desired to generate the rocket launching pressure with the body of the rocket, the acid portion of the charge may be dissolved in the water in the body of the rocket and only the granular sodium bicarbonate placed in the basket. When this procedure is employed, it is advantageous to provide the rocket of the example with a basket which will only contain, for example, 2.8 cc. or approximately 2.3 grams of sodium bicarbonate. The citric acid may then be added in excess directly to the body of the rocket as a solution containing approximately 3 grams of the acid. It has been found that by using 3 grams of citric acid dissolved in 25 cc. of water in the rocket body and with the basket containing 2.3 grams of granular sodium bicarbonate a pressure of about 95 pounds per square inch will be developed within the rocket in about one minute. Again, however, the developed pressure is maintained well below the bursting strength of the rocket body as the quantity of sodium bicarbonate is limited by the capacity of the basket.

Having described my invention in its preferred and modified forms, what is claimed is:

1. A toy rocket comprising an elongate hollow body portion having a closed forward end and an open rear- 6 ward end, a reaction motor releasably mounted in the rearward end of the body portion, said motor including a ring having a passage extending therethrough, a basket releasably secured to the inner end of the reaction motor ring,'said basket being provided with a plurality of slots extending through the side walls thereof, and launching means for the toy rocket including a peg, one end of said peg shaped to snugly engage the passage in said reaction motor, and latch means releasably holding the peg within the passage.

2. The invention defined in claim 1 wherein the slots extending through the side walls of the basket have a width of about .04 inch.

3. A toy rocket comprising an elongate hollow body portion having a pointed nose at the forward end and stabilizing fins at the rearward end, a reaction motor releasably mounted in the rearward end of the body portion, said motor comprising a ring forming a passage extending axially therethrough, a container for a granular gas forming composition releasably mounted to the forward end of said reaction motor ring, said basket having provided in the side walls thereof a plurality of slots, the width of said slots being about .04 inch, and launching means for said rocket including a peg, one end of said peg shaped to be snugly received in the passage in said motor ring, latch means releasably holding the peg within the passage, and a platform receiving the other end of said peg for holding said toy rocket in a launching position.

4. The invention defined in claim 3 wherein said other end of said peg is pivotally mounted to said platform whereby the launching angle of said rocket may be readily varied.

5. The invention defined in claim 1 including resilient sealing means carried by said peg to provide a substantially fluid tight seal between said peg and the passage in the motor ring.

References Cited in the file of this patent UNITED STATES PATENTS 1,347,125 Schneider July 20, 1920 2,594,627 Endicott Apr. 29, 1952 2,732,657 Krautkramer Jan. 31, 1956 2,733,699 Krinsky Feb. 7, 1956 2,759,297 Lewis Aug. 21, 1956 2,771,212 Eifinger Nov. 20, 1956 FOREIGN PATENTS 161,579 Australia Mar. 1, 1955