US 3273553 A
Description (OCR text may contain errors)
A z'ram/ Y5 FIPBZGl Sept. 20, R. H. DOYLE ELECTROMAGNETICALLY OPERATED GUN Filed Sept. 12, 1963 Q4 E W4 mm m PM 2 am 1 WA Q NM ,W NM a g w m P mm. 1 muwssw w N QWRREQR r 4 H n Q United States Patent 3,273,553 ELECTROMAGNETICALLY OPERATED GUN Richard H. Doyle, 104 S. Albert St., Mount Prospect, 11]. Filed Sept. 12, 1963, Ser. No. 308,535 8 Claims. (Cl. 1243) This invention relates to an electric gun for projectiles and, more particularly, to an electrically operated gun for shooting darts or other projectiles formed at least in part of magnetic material.
The types of guns that are now generally available are not well suited for use in the home. Conventional firearms require the installation of indoor range facilities, create excessive noise, and can become rather expensive because of both the cost of ammunition and the initial capital investment required. Guns using spring motors and pneumatic motors are also available and generally do not require extensive indoor range facilities. However, with the possible exception of the more expensive air powered units, these types of guns frequently lack accuracy.
Accordingly, one object of the present invention is to provide a new and improved electrically operated gun.
Another object is to provide an electrically operated gun shooting darts formed at least in part of a magnetic material.
Another object is to provide a gun that is economically manufactured and operated and which possesses the accuracy desired for target shooting.
A further object is to provide an electrically operated gun for use with magnetic projectiles including an operating winding and means for accurately positioning the projectile relative to the operating winding.
In accordance with these and many other objects, an embodiment of the invention comprises an electrically operated hand gun for shooting darts or other projectiles formed at least in part of magnetic material. One projectile that can be used with the gun comprises a dart having a generally elongated body formed of nonmagnetic material to the leading end of which is secured a mass of magnetic material having a point structure. The trailing end of the nonmagnetic body is provided with a plurality of vanes and carries an additional magnetic element.
The gun comprises a housing having both a chamber and an elongated opening adapted to receive the dart. An operating winding is disposed in the chamber with its axial opening aligned at one end with the elongated opening for receiving the dart and at its other end with a barrel structure carried on the housing. A power supply disposed in a hollow handle on the housing is connected between a source of alternating current potential and the operating winding and is selectively controlled by a switch to energize the winding when the gun is to be fired.
To provide means for accurately locating the dart in a desired position within the gun, a permanent magnet disposed adjacent one end of the elongated opening acts on the magnetic element carried on the vaned end of the dart to releasably secure the dart in a predetermined position. This holding means permits the gun barrel to be tipped downwardly and insures that the magnetic mass on the leading end of the dart is properly located relative to the winding means. In addition, the magnetic holding means assists in imparting high velocity to the dart when the gun is operated by retarding movement of the dart under the influence of the energized winding until the flux field developed thereby increases in value to the desired magnitude.
Many other objects and advantages of the present invention will become apparent from considering the following detailed description in conjunction with the drawings in which:
Patented Sept. 20, 1966 FIG. 1 is a fragmentary sectional view of an electric gun embodying the present invention; and
FIG. 2 is a schematic diagram of a control and operating circuit for the gun shown in FIG. 1.
FIG. 1 of the drawings illustrates an electrically operated gun 10 which embodies the present invention and which is adapted to shoot a projectile, such as a dart, indicated generally as 12. The gun 10 shoots the dart 12 with uniform high velocity by selectively energizing a winding 14 under the control of a power supply circuit 16 which is carried on the gun 10 and which is actuated by a manually controlled switch assembly 18.
The dart 12 comprises an elongated tubular or cylindrical shaft or body 20 formed of nonmagnetic material. The leading end of the shaft 20 is provided with a mass of magnetic material 22 formed generally in the configuration -of a prolate spheroid and carrying a point structure 24. The trailing or rear end of the shaft 20 is provided with a plurality of peripherally spaced vanes 26 made of feather or plastic material. A second element 28 of magnetic material is also carried on the rear end of the shaft 20.
The gun 10 includes a housing 30 made of nonmagnetic or plastic material and formed with a somewhat cylindrical head portion 30a and a handle portion 3011. Although the housing 30 can be formed as a single integral construction, it preferably is formed as two matching halves which are secured in face-to-face relationship by a plurality of fastening means 32. The head portion 30a of the housing 30 defines a chamber or cavity 34 and an elongated cylindrical opening 36 for receiving the dart 12. A forwardly projecting nose portion 30c of the head portion 30a of the housing 30 is provided with an opening 42 aligned with the opening 36 for receiving a cylindrical barrel structure 44.
The gun 10 is operated by the operating Winding 14. This winding comprises a plurality of convolutions of copper wire formed in a cylindrical configuration with an axially extending center opening 46. If desired, the wind ing 14 can be potted in a metal tilled epoxy material to provide both electrical insulation and also good heat transmitting characteristics for dissipating heat generated during operation of the gun 10. The winding 14 is disposed within the chamber or opening 34 in the housing 30 with the axially extending opening 46 aligned at its inner end with the opening 36 in the housing and at its outer end with the opening in the barrel structure 44. If desired, an additional layer of dielectric material 48 can be interposed between the winding 14 and the adjacent Walls of the housing 30'.
To provide means for releasably retaining the dart 12 in a predetermined position relative to the operating winding 14, a permanent magnet 50 is mounted on the housing 30 in a position adjacent or closing the end of the opening 36 that is spaced from the winding 14. When a dart 12 is placed in the gun by dropping it into the open end of the barrel structure 44, vaned end first, the dart slides rearwardly relative to the gun 10 through the barrel 44 and the axial opening 46 in the operating winding '14 into the elongated opening 36. When the vaned end of the dart 12 moves into proximity to the permanent magnet 50, the flux field of this magnet acts on the magnetic element 28 to hold the trailing or rear end of the dart I12 in engagement with this magnet. This releasably retains the dart 12 within the elongated opening or chamber 36 in the gun 10 and permits the outer end of the barrel 44 to be moved downwardly without causing displacement of the dart 12. In the normal or retained position illustrated in the drawing, the mass of magnetic material 22 is held within the elongated opening 3 6 spaced from the axial opening 46 in the operating winding 14. However, the mass of magnetic material 22 is within the effective electromagnetic field developed by the winding 14 when this winding is energized.
The power supply circuit 16 provides means for selectively energizing the winding 14. Alth'ough this circuit can comprise any suitable circuit for applying a unidirectional potential to the winding 14,- this circuit preferably comprises one of the type shown in FIG. 2 of the drawings. In general, this circuit comprises a gated silicon rectifier supplied with a 110 volt, 60 cycle alternating current potential and operable to connect the winding 14 directly across the potential source for a single selected half cycle of the potential. Since the direct current resistance of the winding 14 is on the order of .5 to ohms, the winding '14 draws a very large current during the brief period in which it is energized to develop a large electromagnetic field acting on the mass of magnetic material 22 on the dart '12 to propel this dart outwardly through the opening 46 and the barrel 44. a
The power supply circuit 16 preferably is potted in a dielectric material and is secured or mounted. within a cavity 52 in the handle portion 30b of the housing 30. The circuit 16 is supplied with energy from a conventional line cord 54 terminating in a strain relief. insulator 56 that is secured to the handle 30b of the housing 30. The circuit 16 is connected to the winding 14 by a plurality of flexible leads 58 and is also connected to the manually actuated switch assembly 18 by a plurality of flexible leads 60. The switch assembly 18, which can be of any suitable type, is mounted at the junction of the head portion 30a and handle portion 30b of the housing 30 and includes a manually actuated switch operating element 18a, the outer end of which is disposed within a space defined by a trigger guard portion 30d of the housing '30.
To aid in sighting the gun 10, a front sight62 is secured to the forward end of the barrel 44, and a rear sight 64 is mounted adjacent the rear end of the head portion 30a. The rear sight 64 is provided with a longitudinally extending slot 66 through which athreaded fastener 68 extends. By releasing the fastener 68, the vertical position of the rear sight 64 can beadjusted. This sight is clamped between the halves of the housing 30 by tightening the fastener '68.
Referring now more specifically to FIG. 2 of the drawings, therein is illustrated a suitable or representative load control or power supply circuit 16. The circuit 16 connects the winding 14 to an alternating current potential source for all or a selected part of a single half cycle of the alternating current potential. The circuit 16 includes a set of input terminals connected to the alternating current potential source, such as a conventional 60 cycle, 120 volt, single phase source by the line cord 54 and a set of output terminals which are connected to the terminals of the winding 14 by the leads 58.
The circuit 16 includes a gated unidirectional controlled conduction device 72,.such as a silicon controlled rectifier. The anode of the gated rectifier 72 is connected to one terminal of the winding 14 by one of the leads 58, and the cathode of the unit 16 is directly connected to one terminal of the potential source over one of the leads 58 and the line cord 54, although, the relative polarities of the unidirectional conducting components in the circuit 16 can be reversed, if desired. When a positive potential is applied to the anode of the gated rectifier 72 and a trigger signal is applied to the control or gate electrode thereof, the winding [14 is directly connected across the potential source to develop a magnetic field for actuating the dart \12.
The gate electrode of the gated rectifier 72 is provided with an operating or trigger signal under the control of a second controlled conduction device 74, such as a silicon controlled switch. The cathode of the switch 74 is connected to one side of the potential source through a resistance element 76 and is coupled to the control electrode of the gated rectifier 16 through a blocking diode 78. The anode of the switch 74 is connected to a pair of normally open contacts 18a on the manually actuated switch 18 over one of the leads 60. The switch is actuated to close the normally open contacts 18a and to open a pair of normally closed contacts 18b when the control circuit 16 is to connect the winding 14 to the potential source.
The normally closed contacts 18b connect an energy storing means or storage capacitor 80 to a charging circuit including a capacitor 82 that is shunted by a resistance element 84. Positive-going half cycles of the alternating current potential from the source are continuously supplied through a diode 86 to charge the capacitors 80 and 82. When the gun 10 is to be operated, the switch 18 is actuated to open the contacts 18b and to close the contacts 18a. This disconnects the storage capacitor 80 from its charging circuit and connects it to the anode of the second controlled conduction device 74 so as to provide an operating potential therefor. The energy stored in the capacitor '80 is such as to maintain the device 74 in a conductive condition for a period of time no longer than one cycle of the potential supplied by the source.
Inasmuch as the switch 18 can be operated to prepare the device 74 and, thus, the device 72 for conduction at random times relative to the alternations in the potential supplied by the source, it is desirable to synchronize the periods of conduction through the device 74 with the potential supplied by the source so as to insure that the potential applied across the device 72 is of a proper polarity and to insure that the rectifier is fired early enough in the cycle to permit the necessary power to be obtained. To accomplish this, one of the gate or control electrodes of the silicon controlled switch 74 is connected to a difierentiating network including a capacitor 88 and a resistance element 90. The capacitor 88 is connected to the cathode of a diode 92, which cathode is also returned to one side of the potential source through a resistance element 94. The anode of the diode 92 is connected to an adjustable tap on a potentiometer 96 that is connected across two legs of a phase shifting network 98 which is connected across the potential source. The posi tive-going alternations in the potential supplied by the source are differentiated in the network including the resistance element and the capacitor 88 to provide positive-going pulses at the gate electrode of the silicon controlled switch 74.
These positive-going pulses are continuously applied to the controlled conduction device 74 so long as the circuit 16 is energized by the source. However, the device 74 normally is not placed in a conductive condition because of the absence of an operating potential for this device. During the first properly poled half cycle following the time at which the switch 18 is operated to close the contacts 18a, the positive-going pulse supplied to the control electrode of the device 74 places this device in a conductive state so that the storage capacitor 80 is discharged through the resistance element 76. Tthis provides a positive-going pulse that is forwarded through the diode 78 to the gate electrode of the silicon controlled rectifier 72. Since the trigger pulse for the device 74 occurs only during positive-going alternations in the potential supplied by the source, the anode of the device 72 is also at a positive potential with respect to its cathode, and the trigger pulse supplied through the diode 78 places the silicon controlled rectifier 72 in a conductive condition to connect the winding directly across the potential source.
Since the storage capacitor 80 provides sufficient energy for maintaining the device 18 in a conductive condition for no longer than one cycle of the potential supplied by the source and since the silicon controlled rectifier 72 is placed in a nonconductive condition as soon as the potential on its anode swings negative relative to its cathode, the winding 14 can be energized only once in response to the actuation of the switch 18. When the trigger or other controlling means for the switch 18 is released, the switch 18 returns to its normal position to open the contacts 18a and to close the contacts 18b. The opening of the contacts 18a disconnects the storage capacitor 80 from the anode of the silicon controlled switch 74, and the closure of the contacts 18b connects the capacitor 80 in parallel with the capacitor 82 in the charging circuit. The potential supplied by the capacitor 82 as well as that forwarded through the diode 86 rapidly recharges the storage capacitor 80 to again condition the power supply circuit 16 for controlling the next cycle of energization of the winding 14.
Since the power delivered to the winding 14 during any cycle of operation is determined by the portion of the alternating potential half cycle in which the silicon controlled rectifier 72 is in a conductive condition and since the firing of the gated rectifier 72 is dependent on the time at which the silicon controlled switch 74 is rendered conductive, the circuit 16 includes means for controlling the output power developed in the winding '14 by controlling the relative phase relationship between the alternating current potential supplied by the source and the pulses provided by the differentiating network including the capacitor '88 and the resistance element 90. This control is exerted by the phase shift network 98 which comprises a first leg including a resistance element 100* and a capacitor 102 and a second leg including a capacitor 104 and a resistance element 106, both of which legs are connected) in parallel across the potential source. The potentiometer 96 is connected between the two legs at the point of common connection of the elements 100, 102 and 104, 106. The network 98 shifts the phase of the alternating current potential applied to the diode 92 relative to the phase of the potential supplied by the source.
By adjusting the position on the tap of the potentiometer 96, the phase of the signal coupled through the diode 92 can be made to substantially coincidewith the beginning of the positive-going half cycle of the potential from the source so that all of the power available in the half cycle can be used by triggering the silicon controlled rectifier 72 at the beginning of the selected positive-going half cycle. Alternatively, the tap on the potentiometer 96 can be adjusted to provide a delay approaching onehalf of the positive-going half cycle so that the differentiating network triggers the controlled conduction devices 72 and 74 after substantially half of the half cycle has passed. This reduces the power available for use by the winding 14 by a factor approaching two. In this manner, the phase shift network 98 permits the power supplied by the circuit 16 to be easily adjusted without requiring the use of components connected in series between the potential source and the winding 14.
When the gun is to be operated, the vaned end of the dart 12 is placed in the open end of the barrel 44, and the dant 12 is released to permit it to fall downwardly through the barrel 44 and the axial opening 46 into the elongated opening or chamber 36. When the magnetic element 28 on the dart 12 moves into proximity to the permanent magnet 50, it is attracted into engagement with this magnet so that the dart 12 is releasably retained in a proper position within the opening 36 with the mass of magnetic material 22 disposed in proximity to but spaced from the operating winding or coil 14. The dart 12, by virtue of its magnetic retention within the opening 36, will not be displaced from its proper position even when the end of the barrel 44 is pointed downwardly. This permits the gun 10 to be aimed at objects or targets disposed below the level at which the gun is held.
The gun 10 is fired by depressing the operator element 18a on the switch assembly 18. The operation of the switch assembly 18, controls the power supply circuit 16 so that the next complete positive-going cycle of alternating current input potential supplied by the line cord 54 is applied directly across the winding 14. In response to energization, the winding 14 develops an electromagnetic field which acts on the mass of magnetic material 22 and attempts to move this mass inwardly toward the magnetic center of the operating Winding 14 to reduce the reluctance of the external air gap. The initial movement of the mass of material 22 and thus of the dart 12 is retarded by the magnetic attraction between the permanent magnet 50 and the magnetic element 28. This permits the field produced by the energization of the winding 14 to develop to a high enough value that when the dart 12 begins to move, a fairly high rate of acceleration is achieved. The electromagnetic forces acting on the mass of magnetic material 22 propels this material and the dart 12 through the axial opening 46 and into the barrel 44 with enough velocity that it passes the magnetic center of the winding 14 and is propelled outwardly through the open end of the barrel 44. It is desirable that the permanent magnet 50 only partially closes the rear end of the opening 36 or that other means, such as a vent passage in the housing 30 communicating with the opening 36, be provided to prevent the formation of a vacuum behind the dant 12 when it is propelled. The formation of a vacuum tends to retard the acceleration of the dart 12.
The propulsion of the dart 12 is also enhanced by an annular ring of electrically conductive material 108 that is disposed on the nose portion 300 of the housing 30 adjacent or directly against one end of the winding 14. The annular element 108 provides a shorted turn or bucking coil to delay the collapse of the field developed by the winding 14 and thus extends the duration of the electromagnetic field for propelling the dart 12. In effect, the element 108 provides a single turn coil linked by the flux field of the winding 14 in which a relatively large current is induced when the winding 14 is energized. This induced current tends to retard the collapse of the flux field developed by the winding 14 when the power supply circuit 16 terminates the energization of this winding.
The power supply circuit 16 is capable of delivering only a single pulse of energy through the winding 14 each time that the switch assembly 18 is actuated. Thus, the winding 14 will be energized only once in response to each manual actuation of the operator element 18a. The gun 10 is restored to a normal condition by releasing the switch assembly 18. Since the winding 14 is energized for only one positive-going or negative-going cycle of the input potential, the heat generated by the winding 14 is not excessive and does not cause heating of the gun 10.
In one gun 10 constructed in accordance with the present invention, the control circuit 16 applies 8-l0,000 watts of power to the winding 14 for a part of one cycle of the 110- volt, 60 cycle input potential. This energization of the winding 14 produces acceleration of the dart 12 on the order of 30,000 feet/sec/sec. with this dart attaining terminal velocities in excess of feet per second. The gun 10 is completely silent in operation, lacks any moving parts that might result in malfunction or require replacement, and can be operated to provide over 10,000 shots at a cost of less than one cent for the electrical power consumed.
The control circuit 16 can also be of the type in which a capacitor charged by a direct current potential supplied from the alternating current potential source through a rectifying network or supplied by a battery is discharged through the winding 14 in a short time interval under the control of the switch means 18. With this type of control circuit 16, the resistance of the winding can be reduced to a value less than one ohm with an inductance on the order of .002 henry to permit a peak driving current of around 300 amperes. This applies from 200 to 300 watt-seconds of energy to the winding 14 to obtain rates of acceleration and terminal velocities as well as ranges of operation greater than those obtained with the control circuit 16 previously described.
Although the present invention has been described with reference to a single illustrative embodiment thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of the present invention.
What is claimed as new and desired to be secured by Letters Patent of the United States is:
1. An electric gun for use with projectiles having a magnetic end part and a magnetic portion comprising a housing having a depending hollow handle and an elongated opening, said housing also having an enlarged chamber adjacent one end of the elongated opening, winding means mounted in the chamber and having an axial opening disposed in alignment with the elongated opening, a barrel mounted on the housing in alignment with the elongated opening and the axial opening, permanent magnet means carried on the housing adjacent the other end of the elongated opening and cooperating with the magnetic end part on the projectile to releasably secure the projectile in the elongated openingwith the magnetic portion disposed adjacent the winding means, said permanent magnet means being spaced from the winding means by substantially the full length of the projectile to separate the permanent magnet means from the field of the winding means, power supply means mounted within the hollow handle and connceted to the winding means, said power supply means comprising a control circuit means connected between a cycling po-' tential source and said winding means for connecting the winding means to the potential source for a period of time no greater than one cycle in the potential; supplied by the source, and manually operable means carried on the housing for controlling the operation of the control circuit means. 1
2. An electric gun energized by an undulating potential source for propelling a projectile having a magnetic portion comprising a housing having a barrel structure, winding means on the housing including an axial opening aligned with the barrel for receiving the projectile, control circuit means connected between the undulating potential source and the winding means for connecting the winding means to the potential source for a period of time no greater than one undulation in the potential supplied by the source, and manually operable means carried on the housing for controlling the operation of the control 'circuit means. a
3. An electric gun adapted to be energized by an alternating current potential source to propel a projectile formed at least in part of magnetic material comprising a housing including a barrel structure communicating with an elongated opening in the housing adapted to receive the projectile, winding means on the housing and encircling at least a portion of the opening at -a position disposed in proximity to the magnetic part of a projectile in the opening, control circuit means connected between the alternating current potential source and the winding means and operable to connect the winding means to the potential source for a period of time no greater than one cycle of the potential, and manually operable means on the housing for controlling the operation of the control circuit means.
' body portion of the housing in a portion immediately 4. A gun energized by an alternating current potential source for propelling a projectile having a magnetic portion comprising a housing having an elongated body portion and a handle portion extending generally transverse to thebody portion, the handle portion having a first cavity and the body portion having an elongated opening closed at one end and extending in the direction of elongation of the body portion, the body portion also having a second cavity surrounding the elongated opening and disposed intermediate the ends thereof, winding means disposed in the second cavity and having an axial opening aligned with and forming a part of the elongated opening, retaining means for rele-asably retaining a projectile in the portion of the elongated opening disposed between its closed end and the winding means, a power supply circuit mounted in the first cavity in the handle portion and operable to control the connection of the winding means to the potential source, first flexible electrically conductive means connected to the power supply circuit for coupling the power supply circuit to the potential ource, second electrically conductive means for connecting the power supply circuit to the winding means and extending from the first cavity in the handle portion of the housing to the second cavity in the body portion of the housing, and manually operable switch means connected to the power supply circuit and mounted on the housing adjacent to the junction of the body portion and the handle .portion. V
, 5. The gun set forth in claim 4 including an annular means of electrically conductive material mounted on the adjacent to the end of the winding means spaced away from the closed end of the elongated opening.
6. The gun set forth in claim 5 in which the body portion of the housing'includes a forwardly extending projection surrounding the elongated opening on which the annular means is mounted.
7. The gun set forth in claim 4 including a barrel carried on the housing at the end of the body portion spaced from the closed end of the elongated opening and forming a part thereof.
8. The gun set forth in claim 4 in which the switch means is mounted within the housing and includes an operator means projecting outwardly from the housing.
References Cited by the Examiner UNITED STATES PATENTS 1,167,178 1/1916 Hill 124-3 X 1,241,333 9/1917 Bowman 1243 1,565,895 12/1925 Blaustein 124--3 1,883,773 10/1932 Erickson 317-184 X 2,499,029 2/1950 McElroy 273106.5 2,659,998 11/1953 Cavanaugh 46243 X 2,736,308 2/1956 Ferrando et a1. 124-13 2,786,461 3/1957 Pelsue 124--41 X 3,059,630 10/1962 Oreskey 12427 3,142,294 7/ 1964 Baldwin 124-27 X RICHARD C. PINKHAM, Primary Examiner.
W. R. BROWNE, Assistant Examiner.