US3043105A - Chamber for expending consumable charges and charging apparatus therefor - Google Patents

Description

I July 10, 1962 Filed Dec. 19, 1958 J. P. HAGERTY CHAMBER FOR EXPENDING CONSUMABLE CHARGES AND CHARGING APPARATUS THEREFOR 3 Sheets-Sheet 1 dos-m P. HAGERTY a QM A'rroRiEYS July 10, 1962 J. P. HAGERTY 3,043,105

CHAMBER FOR EXPENDING CONSUMABLE CHARGES AND CHARGING APPARATUS THEREFOR 3 Sheets-Sheet 2 Filed Dec. 19, 1958 INVENTOR. Jon-m P. HAGERTY ATTQQMIYS July 10, 1962 J. P. HAGERTY 3,043,105 CHAMBER FOR EXPENDING CONSUMABLE CHARGES PPARATUS THEREFOR AND CHARGING A 3 Sheets-Sheet 3 Filed Dec. 19, 1958 INVENTOR.

7 JOHN P-HAGERTY 7 QM f 63% 3,043 105 r; as non Exrnrtnmc CQNSUMAELE cannons cnsc APPARATUS John P. Hagerty, Box 470, Rte. 8, Tucson, Ariz. Filed Dec. 19, 1958, Ser. No. 781,594

3 Claims. (til. Gil-39.47)

and means for successively supp-lying new fuel charges to' the chamber as previous ones are consumed.

Solid'fuel rockets have many advantages over those employing liquid oxygen which combines with other liquids as the fuel. Solid fuels generally are safer and easier to handle, and the combustion thereof is more easily controlled. In many instances a higher thermal efiiciency can be obtained in a rocket employing such fuel. When solid" fuels are burned in a conventional combustion chamber, the combustion space increases as the fuel is consumed. This tends to cause the pressures established by the products of combustion to decrease as the space increases and thereby to decrease the reaction forces obtainable when the combustion products are emitted through an exhaust nozzle. the combustion space may also affect the combustion characteristics of the fuel.

To overcome the above; disadvantages, the present invention provides a chamber in which 'a'consumable charge is expended with means for moving the remaining portion of the charge toward an exhaust opening in the chamber as the charge is consumed, and thereby maintain the size of the space between the charge and the exhaust opening substantially constant.

The invention also provides a novel and useful means for sequentially supplying additional charges to a combustion chamber in order to prolong the period of operation of the engine.

The invention may also find many other applications, such as to supply thrust power to drive an impulse or reaction turbine." The charging apparatus per se has other uses, for such purposes as sequentially supplying carbon dioxide cartridges for soda fountains or fire fighting equipment. The charging apparatus can also be used as an improved rotating magazine and charging device for firearms.

. It is,.therefore, a principal object of the invention to provide apparatus including a chamber in which a consumable charge can be expended, with improved means for sequentially supplying additional consumable charges thereto. v

Another-object of the invention is to provide an improved combustion chamber, the combustion space of which can be maintained constant as a charge therein is consumed.

Other objects and advantages of the invention will be apparent from the following detailed description of a specific embodiment thereof, reference being made to the accompanying drawings, in which' FIG. 1 is a schematic view of a missile embodying a rocket engine according to the invention; 7

FIG. 2 is an elevational view, with parts broken away, of the rocket engine shown in FIG. '1;

FIG. 3 is an enlarged, fragmentary, longitudinal sectional view of the rocket engine;

FIG. 4 is a view in cross section taken on the line 4--4 of FIG. 3;

The variation in the size of dflthidd Patented July 10, 1952 FIG. 5 is an enlarged view in cross section taken on the line 5-5 of FIG. 4;

FIG. 6 is a view in cross section of the magazine section taken on the line 6--6 of FIG. 3, with bolt and ram parts omitted;

FIG. 7 is a fragmentary, cross-sectional view of a consumable charge employed with the rocket in association with a portion of a firing mechanism employed therewith;

FIG. 8 is an end elevation of the firing mechanism shown in 'FIG. 6; and

FIG. 9 is a diagrammatic view of a control circuit suitable for use with the rocket.

Referring to FIG. 1, a missile =10 embodying the invention comprises a power section 12, an explosives section 14, and a nose section 16 which can contain suitable guidance equipment and cooling apparatus for a rocket engine 18 in the power section 12. The rocket engine 18 (FIGS. 2 and 3) basically includes an exhaust nozzle or opening 26, a combustion chamber 22, a magazine 24, a loading cylinder 26, and a drive mechanism shown generally at 28. A consumable charge 3! is shown in position in the combustion chamber 22. Such a charge comprises a body of solid, burnable fuel carried within a casing 32 of a suitable material which is consumed or burned as the solid fuel is burned.

A firing mechanism 34 (FIGS. 7 and 8) is mounted in anannular flange 36 at the forward end of the casing 32 and includes a powder case 38 having a plurality of flame ports 40, which communicate with the solid fuel in the casing 32, and a percussion cap 42 at one end thereof. Two ears 44 extend inwardly from the case 33 and support an axle 46 which is aligned with and extends into the hollow end of a rod 48, slidably supported in a housing 50 attached to the case 38. A hammer 52 is pivotally held on the axle 46 and is powered by a spring 54 which is looped over the axle 46 with one end abutting a portion of the ears 44-. The other end of the spring, which is shown in an unactuated position, can be actuated to drive the hammer 52 by engaging it in an arming notch 56 just before the charges are loaded in the rocket engine. The hammer 52 is prevented from moving by an enlarged tip 58 of a scar 66} which extends through rectangular holes in the ears 44 and is afiixed to the forward end of the rod 48. The rod extends longitudinally through the casing 32 and has an enlarged portion 62 slidably held in a tube 64 at the rear end of the casing. When the rod 48 is moved forwardly, it moves the sear 6t} and the enlarged tip 58 forwardly to cause the tip 58 to become disengaged from a notch in the hammer 52, which, then being free to move, is driven by the spring 54 and strikes the percussion cap 42 to ignite the powder in the case 38. Burning com-bustion products from this powder are emitted through the ports 40 and ignite the solid fuel in the charge 39. The force of the burning solid fuel ejects the firingmechanism 3.4 through the exhaust nozzle 2% The components of the firing mechanism can be made of a low melting alloy so that they may be ejected in a molten state, or of combustible materials so that they maybe consumed with the burning ,of the solid fuel.

Before the missile is fired, one of the charges 30 is manually placed in the combustion chamber 22 against stop or shoulder 65 (FIG. 2.) therein, with no mechanized load step being necessary until this charge is consumed. Subsequent charges, however, are transferred to the chamber 22 from the magazine section 24 and the loading cylinder 26 by means of a bolt 66 (FIGS. 3 and 4). The bolt has a sealing ring 68 which seats against a tapered member 70 at the rear of the combustion chamber 22 when the bolt is in its forward operating position. The bolt is notched on its periphery to provide keyways 72 one of which engages a key 74 at the rear of the loading cylinder 26 and is reciprocated by means of a worm gear 76 rotated by a drive rod 78 engaged in a crank dog 80 and driven by a motor 82 (FIG. 1). The bolt 66 is connected to the worm gear 76 through a housing of a magnetic ram clutch 84 and the housing of a ram motor 86, and the dog 80 is operatively connected to the gear 76 through a magnetic bolt clutch 88. The worm gear 76 engages worm gear racks 90 longitudinally dis posed in a housing 92. The keyways 72 ride over the worm racks 90 when the bolt 66 is near its rearward position.

A ram 94 is carried in the bolt 66 and constitutes a means for moving the charge 38 forwardly as it is consumed to maintain the space between the charge and the exhaust opening 20 constant. The ram has a projection 96 which, when in its forward position, strikes the enlarged portion 62 of the rod 48 and fires the mechanism 34 to ignite the charge as above described. Near the rear end of the ram 94 is an internal worm gear follower 98 which engages a worm rod 100 operatively connected to the magnetic ram clutch 84, so that the rod is rotated by the motor 86 whenever clutch 84 is energized. The ram is in sliding contact with the inner surfaces of the keyways 72 and has radially extending members 102 (FIG. 4) coacting therewith to prevent rotation of the ram during forward and rearward movement thereof. The ram 94 is driven in a forward direction at a predetermined rate equal to, but independently of, the burning rate of the solid fuel in the charge 30, and so moves until the charge 30 is consumed.

When a charge has been consumed, the pressure in the exhaust opening 20 decreases abruptly. A pressure switch 104 (FIG. 2) communicating with the exhaust opening through a tube 106 is tripped by this sudden pressure change. As will be more fully described, the switch 104 causes reversal of the motors 82 and 86 to cause the bolt 66 to retract beyond the rear of the loading cylinder 26 and to cause the ram 94 to retract into the bolt. When the bolt 66 reaches its rear position, thegear 76 actuates a limit switch 108 (FIG. 2) which reverses the motor 82 and again drives the bolt forwardly to push another charge from the cylinder 26 into the chamber 22. When the bolt I 66 reaches its forward position, with the ring 68 sealed against the tapered member 70, the gear 76 trips a limit switch 110 which stops the motor 82 and starts the motor 86 in a forward direction once again. The engagement of the gear 76 with the racks 90 holds the bolt 66 tightly with respect to the combustion chamber 22 and prevents any gas leakage from the chamber 22.

The charges 30 are transferred from the magazine 24 to the loading cylinder 26 by rearward movement of the bolt 66. As the bolt 66 approaches its rearward position upon retraction after the charge 30 is consumed, a spring loaded pawl 112 (FIG. 5) carried by the bolt engages in a helical slot 114 (FIG. 2) in a cylinder 118 rotatable about a hollow cylindrical hub 120 between the loading cylinder 26 and the housing 92. The pawl 112, which can only move in a lineal direction with the bolt 66, causes the cylinder 118 to rotate about the hub 120 by engaging in the helical slot 114 as the pawl moves rearwardly. The hub 120 has a longitudinal opening through which the pawl 112 can extend from the bolt 66 into the slot 114.

The cylinder 118 is attached to the magazine 24 which has a plurality of semi-cylindrical receptacles 122 (FIG. 6) each of which holds one of the consumable charges 30. Each charge is urged inwardly and out of its receptacle 122 by a loading arm 124 which is urged inwardly by a spring 126 (FIG. 2). However, the charges are held in the receptacles 122 by means of retaining arms 128, the inner ends of which ride on the outer surface of the loading cylinder 26. When the retaining arms reach one edge of an opening 130 in the cylinder 26, they can no longer offer resistance to the downward force of the loading arms 124 and, therefore, swing out of the way to enable the arms 124 to push the charge 30 into the cylinder 126. At the other edge of the opening, the retaining arms are forced upwardly and out of the way again, as are the loading arms 124. A new charge is pushed into the loading cylinder 26 each time the magazine 24 is rotated to bring a charge into alignment with the opening 130 in the cylinder.

After the charge 39 is transferred into the cylinder 26, the bolt 66 is moved forwardly to push the charge 30 into the chamber 22. When the bolt reaches its forward position, the limit switch 110 is tripped causing the motor 86 to drive the ram 94 forwardly, striking the portion 62 of the rod 48 to ignite the charge.

The symmetrical position of the magazine 24 around the cylinder 26 is particularly advantageous because it enables the charges to be symmetrically located around the center line of the combustion chamber 22 so that a missile body of minimum diameter can be employed. By using a single combustion chamber, rather than burning each of the charges 30 in its own receptacle 122, a much lighter weight is possible because light construction materials can be used throughout the rocket, with the exception of the combustion chamber.

While it is understood that various means can be employed to control the motions of the charging mechanism and the ram, the following discussion and FIG. 9 illustrate a circuit by means of which effective control can be established. v

The circuit of FIG. 9 employs the switches 104, 108 and 110, each of which is shown in an unactnated position. The limit switch 108 is of a conventional type with a core extension 132 and contacts 134. The pressure switch 104 is connected to a limit switch 136 through a line 138 with both the limit switches 110 and 136 being of the latch and trip type, each of these components being designated L and T, respectively. The latter two limit switches have core extensions 140 and 142 with double sets of contacts 144, 146 and 148, 150, respectively. Current may be from any suitable source such as a battery 152 grounded at 154 and connected to a main lead line 156. Current is supplied to the bolt motor 82 and the magnetic bolt clutch 88 through lines 158, 160, 162 and 164, and hence to a ground 166 through lines 168, 170, 172 and 174. Current is supplied to the clutch 88 and the motor 82 in the reverse direction through lines 176, 178 and the lines 174, 172, 170 and 168, and hence to a ground 180 through the lines 164, 162, 160 and a line 182. Current is supplied to the ram clutch 84 and the ram motor 86 to drive the ram 94 in a forward direction by means of lines 184, 186, 188, 190 and 192, and hence to the ground 166 through lines 194, 196, 198 and the line 174. Current is supplied to the clutch 84 and v the ram motor 86 in the reverse direction through the lines 176, 178, 174, 198, 196 and 194, and hence to a ground 200 through the lines 192, 190, 188 and a line 202.

The circuit functions as follows: When the bolt 66 is moving forwardly with the ram 94 stationary therein, all of the switches are unactnated and are in the positions shown in FIG. 9. In these positions, the contact 144 of the limit switch connects the lines 158 and and the contact 148 of the limit switch 136 connects the line 174 and the ground 166 so that current is supplied to the bolt motor 82 in a forward direction and, with the clutch 88 engaged, moves the bolt 66 forwardly. At the same time, the lines 184 and 186 are disconected which prevents the ram motor 86 from being actuated and the ram clutch 84 from being engaged. Thus, the ram 94 remains stationary with respect to the bolt 66. When the bolt 66 reaches its forward position, with the sealing ring 68 seated against the tapered member 70, the limit switch 110 is actuated by the gear 76, causing the contact 144 to connect the line 182 and the ground and also causing the contact 146 to connect the lines 184 and 186. The contacts remain in these positions until the latch is released when the trip is actuated. Current is now supi plied through the lines 184 and 186 to the ram motor 86 and the clutch 84 and hence through the line 174 to the ground 166 to cause the motor 86 to drive the ram forwardly. At the same time, the lines 158 and 160 are open to prevent the flow of current to the bolt motor 82. A resistance 204 is located in the line 186 to control the speed of the motor 86 to drive the ram 94 at a forward rate equal to the rate at which the charge 30 is consumed.

When the charge is completely consumed, the pressure in the exhaust opening 20 abruptly decreases and causes the pressure switch 164 to actuate the limit switch 136.

This limit switch causes the contact 148 to connect the lines 176 and 178 and also causes the contact 150 toconmeet the line 202 to the ground 200; the contacts 144 and 146 still remain in their actuated positions, the limit switch 110 not being tripped. With these positions of the contacts, current flows through the lines 176 and 178 to the motor 82 and hence through the line 182 to the ground 180. This drives the motor 82 in the reverse direction. Similarly, current flows through the lines 176, 178 and 174 to the motor 86 and hence to the line 202 and the ground 2.00 to drive the motor 86 in the reverse direction. The bolt 66 thus retracts toward the rear of the rocket and at the same time the ram 94 retracts into the bolt 66. The ram $4 moves rearwardly more rapidly than forwardly because current does not flow through the resistance 204, and the ram is fully retracted into the bolt by the time the bolt reaches its rear position.

When the bolt 66- is at the rear position, the gear '76 depresses and actuates the limit switch 108 to cause the contacts 134 to connect lines 296 and 263 to supply current therethrough to trip the latch of the limit switch 110 and through a line 210 to trip the latch of the limit switch 136, and hence to a ground 212. The contacts of the limit switches 110 and 136 thereby return to their tripped,

unactuated positions to supply current again to the clutch 8S and the bolt motor 82 to move the bolt 66 forwardly. At the same time, the contacts 146 open to prevent flow of current to the ram motor 86. The bolt 66 thus again moves forwardly and the ram 94 remains stationary, retracted in the bolt 66. This condition exists until the Limit switch 110 is again tripped and the cycle repeats.

Theoverall operation of the rocket motor 13 is now set forth. Before the missile is fired, the rocket is manually loaded with seven of the charges 36, including six in the semi-cylindrical receptacles 12 2 and one in the combustion chamber 22. The bolt 66 is in its forward position at this time with the sealing ring 68 seated against the member 70. When ready for firing, the ram @4, which is in its rear position and sufiiciently is recessed in the bolt 66 to prevent the projection 96 from striking the rod 48, is moved toward its forward position by means of the ram motor 86. When the projection 96 strikes the enlarged portion 62 of the rod 48, the enlarged tip 58 of the sear 60 is pushed out of the notch in the hammer 52 and enables the spring 54 to swing the hammer 52 against the percussion cap 42. Explosion of the percussion cap 42 ignites the ignition powder in the case 38 and burning combustion gases are emitted through the ports 46 into the solid fuel in the casing 32. The firing mechanism 34 is then ejected through the exhaust opening 26 as the fuel burns, with the combustion products also emitted through the exhaust opening 20 to produce thrust. The fuel burns relatively uniformly over the lateral area of the casing, and as it burns back toward the rear of it, the casing is pushed against the stops 65 by the ram 94 to maintain the combustion space constant between the remaining portion of the charge 30 and the nozzle 20. When the charge is consumed and the ram 94 is moved to its forward position, the pressure drops and the pressure switch 104 actuates the switch 136 to reverse the direction of the motors 82 and 86. The ram 94 is thereby retracted into the bolt 66 as the bolt is retracted to the rear of the loading cylinder 26 which causes the pawl 112 disengaged from the slot 114 due to the slanted contiguration of the upper end of the pawl which causes it to be pushed out of the slot 114 and under the wall of cylinder 7 118. The belt moves the new charge into the chamber 22 until the sealing ring 68 seats against the member 70, at which time the limit switch 110 is depressed and the motor 86 moves the ram 94 forwardly to fire the new charge and push it toward the exhaust opening to keep the combustion space constant.

Apparatus according to the invention basically comprises a chamber, a consumable charge for the chamber, and means for urging the charge toward an exhaust opening in the chamber at the same rate that the charge is consumed, to maintain a substantially constant space between the remaining portion of the charge and the exhaust opening.- The invention also comprises a chamber, a consumable charge for the chamber, a loading cylinder aligned with the chamber, means for holding a plurality of additional charges around the loading chamber, means for transferring charges from the magazine to the loading chamber, and means for moving the charges from the loading chamber into the consuming chamber.

It is to be understood that although only one specific form of the invention has been disclosed, various modifications for numerous applications can be made without departing from the scope of the invention as defined in the appended claims. I

What I claim is:

1. Apparatus for sequentially consuming a plurality of charges, said apparatus comprising a chamber in which a charge is consumed, said chamber having an exhaust opening at one end thereof through which products given off by the charge are exhausted, a loading cylinder aligned with said chamber in fixed relationship with respect thereto, said cylinder having an opening in a side wall thereof, charging means movable in said cylinder to transfer a charge from said cylinder into said chamber, means for maintaining a plurality of charges circumjacent said loading cylinder, saidmeans communicating with said opening of said loading cylinder, and means for sequentially transferring said charges directly to said loading cylinder laterally from said latter means when said charging means is at the rear thereof.

2. Apparatus for sequentially consuming a plurality of charges, said apparatus comprising a chamber in which a charge is consumed, said chamber having an opening at one end thereof through which products of the charge are exhausted, a loading cylinder aligned with said chamber adjacent the end thereof opposite the opening, charging means movable in said cylinder to transfer a charge from said cylinder into said chamber, wall means forming a plurality of connected receptacles equally spaced around said loading cylinder for holding a plurality of charges, means actuated by said charging means when atrthe rear of said loading cylinder for rotating said wall means around said cylinder, and means for transferring the charges individually directly from said wall means laterally to said loading cylinder when said wall means are rotated.

3. Charge apparatus for sequentially supplying consumable charges to a chamber, said apparatus comprising a loading cylinder adapted to be positioned adjacent an end of the chamber and aligned therewith, said cylinder having an opening in a side wall thereof, a charging bolt slidably movable in said cylinder, means for driving the bolt away from said chamber and toward the rear of the loading cylinder, a plurality of connected receptacles mounted for rotation about said loading cylinder in cir- 5 cumjacent relationship with respect thereto for sequentially placing additional fuel charges adjacent said opening in the loading cylinder, means actuated by said bolt for transferring another charge to said loading cylinder when the 'bolt is at the rear thereof, and means for driving the 10 bolt forward to move said charge into said chamber.

References Cited in the file of this patent UNITED STATES PATENTS

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