Charging System For Electric Bomb Fuzes (u)

Abstract

An electric bomb charging device self-contained within the bomb requiring external charging gear. The device is placed within a charging well located along the longitudinal surface of the bomb and is adapted so as to receive the slipstream of air flowing along the bomb's surface after it is released from the aircraft. The charging device transforms the air slipstream into the electrical energy necessary to operate a proximity sensor and electric fuze located within the bomb. The device is provided with a protective cover that is removed by a lanyard only upon the bomb's release, and a minimum threshold velocity must be attained before the charging device is actuated. In a first embodiment form, the device is comprised of a modified fluidic generator, while in a second embodiment it takes the form an anemometer-type vane coupled with an electric alternator. Both embodiments employ electronic circuits to regulate the output voltages derived therefrom.

Description

RIGHTS OF GOVERNMENT

The invention described herein may be manufactured, used, and licensed by or for the United States Government for governmental purposes without the payment to me of any royalty thereon.

BACKGROUND OF THE INVENTION

This invention relates generally to charging devices and, more particularly, to environmental charging systems that provide energy for electric bomb fuzes.

Many of the electrical bomb fuzes now in standard use require complex external charging equipment for providing electrical energy to the fuzing system. In addition to their unwieldy structure, such equipment requires the use of special bomb mounting racks and plug-in connectors not ordinarily found on aircraft. This type of charging gear occupies a great deal of space, which frequency precludes its use in special aircraft that use all existing space to accommodate other vital control equipment as needed, for example, in aircraft that carry atomic bombs. The special electric charging gear in current use is installed and designed so that the electric bomb fuzes are energized while falling from the aircraft just after release. Upon release, the charging gear is disengaged and the fuze becomes fully charged and ready for arming. The safety of the bomb is dependent on the reliability of the various safety devices in the fuze to prevent arming until the bomb has fallen a safe distance from the aircraft. A malfunction of the charging or releasing gear occurring, for example, while the plane is still on the ground, would lead to a premature detonation of the bomb causing serious injury to the aircraft and/or crew members.

Accordingly, a primary object of the present invention is to provide a charging system for electric bomb fuzes that positively will not energize the fuze until a prescribed minimum velocity is attained.

Another object of the present invention is to provide a charging system for electric bomb fuzes that is reliable, foolproof, easily adaptable to existing bomb structures, and has a minimum of moving parts.

A further object of the present invention is to provide a charging system for electric bomb fuzes that requires no special mounting racks or connectors for its utilization in existing bomb structures.

A still further object of the present invention is to provide an electric bomb charging device that is dependent for its actuation upon the release of the bomb from the aircraft.

SUMMARY OF THE INVENTION

The aforementioned and other objects may be obtained by using a charging device that is self-contained within the bomb and requires no external connections or special mounting racks for its actuation and support. The device of the present invention is placed within an existing charging well of common electrically fuzed bombs and is adapted to receive the slipstream of air flowing along the bomb's surface subsequent to its release from the aircraft. The device converts the energy of the slipstream into electrical energy that powers the bomb fuze; no activation is possible in the absence of a slipstream. The device is shielded from mud, air and condensation prior to release by a lanyard-operated cover that is removed only upon release. Further safety is assured in both embodiments by requiring a minimum bomb velocity prior to their actuation.

BRIEF DESCRIPTION OF THE DRAWINGS

The specific nature of the invention, as well as other objects, aspects, uses, and advantages thereof will clearly appear from the following description and from the accompanying drawing, in which:

FIG. 1 is a partially cut away illustration of a commonly used electric-fuze bomb in combination with an environmental charging device of the present invention;

FIG. 2 is a cut away view of a fluidic charging device of the present invention; and

FIG. 3 is another embodiment of a charging device of the present invention utilizing an electro-mechanical generator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates generally at 10 a very common configuration of a high-explosive electrically fuzed bomb for which the device of the present invention is intended. At 12 is depicted the environmental charging device of the present invention located within and secured by the center charging well 14 of bomb 10 located approximately at the longitudinal midpoint of the bomb as shown in FIG. 1. A cover 16 shields the device 12 from the outside environment until ready for use. Charging device 12 provides electrical power by means of a multiwire cable 24 to a proximity sensor 22 located in the nose of the bomb and by means of a multiwire cable 28 to an electric bomb fuze 26 located aft.

Bomb 10 remains inactive until it is released. Upon release, cover 16 is removed automatically by an arming lanyard 18 attached to the aircraft by means of a pin 20. The exposure of the charging device 12 to the air slipstream that flows past bomb 10 after release actuates generators within the device 12 in a manner described more fully below. The threshold level of proximity sensor 22 is preselected such that when bomb 10 is at the optimum distance from the target, sensor 22 emits a signal back through cable 24 and through cable 28 to fuze 26 to detonate the bomb. In the event of the failure of sensor 22 to emit said signal, fuze 26 is equipped with point detonation capability in a manner well known in the art.

FIG. 2 illustrates one preferred embodiment of environmental charging device 12 of FIG. 1 in the form of a modified fluidic generator. Cover 16 is shown in its pre-release position, sealing the device so that mud, water or air cannot enter the device prior to release. When arming lanyard 18 positively removes cover 16, the slipstream of air along the surface of the bomb enters a resonant cavity 32 and vibrates back and forth in the cavity at a preselected frequency according to the dimensions of the cavity 32. The vibrations of air in the cavity cause diaphragm 34 to oscillate. Excess air is exhausted to the atmosphere through vent 33. The oscillations of diaphragm 34 are transmitted by means of a rod 36 to a metallic reed 38 which in turn vibrates between the poles of a permanent magnet 40. The motion of reed 38 tends to switch the magnetic field set up by magnet 40 and thus induce an emf in a coil 42 surrounding reed 38. This induced emf is subsequently stepped up by transformer 44 and is rectified and limited to the desired level by a rectifier and voltage limiting circuit 45. The operating voltage needed for the proximity sensor 22 of FIG. 1 is coupled thereto by means of cable 46 which is comprised of a three-wire line consisting of a ground wire, a hot wire, and a wire to transmit said detonating signal from sensor 22 back to device 12 and through cable 48 to fuze 26 of FIG. 1. A potting compound 50 protects the electronic components and cables from shock and vibration. The safety features of the device 12 are now apparent. The generator will operate only after the protective cover 16 is removed and the bomb is moving above the preset minimum velocity necessary to cause oscillation of the air in the resonant cavity 32. This minimum velocity requirement means that the fuze cannot energize until the aircraft is indeed in flight and is exceeding the prescribed minimum velocity.

In FIG. 3 is shown another embodiment of the charging device 12 of FIG. 1. This embodiment consists of a multipole alternator 52 which is driven by an anemometer-type vane 54. Anemometer vane 54 is locked in a fixed position by a cover 16 which is O-ring sealed to the retaining nut 56. Tabs (not shown) are turned under the nut 56 flange which require a minimum pull force to remove cover 16. Cover 16 is fitted with arming lanyard 18 attached to the arming solenoid (not shown) on the rack of the aircraft by means of ring 20. Cover 16 is removed from the device 12 by arming lanyard 18 upon release of the bomb. The dsign of alternator 52 is such that the magnetic lock of the rotor will prevent rotation of vane 54 up unless a preselected minimum air velocity is attained with cover 16 removed. Excess air is exhausted to the atmosphere through vent 53. A transformer 60 steps up the AC voltage thus generated while a voltage doubler and rectifier circuit 58 increases the rise rate of the voltage and converts the generator output from AC to DC. Zener diodes (not shown) can be used to regulate the output voltage to the desired level to operate proximity sensor 22 and fuze 26 of FIG. 1. The necessary signals are transmitted to the latter two devices by means of cables 46 and 48, respectively.

The two embodiments shown in FIG. 2 and FIG. 3 are both particularly designed to derive their power for operation from the slipstream of air flowing along the longitudinal surface of the bomb after it is released. In this manner, reliability of opeation and pre-release safety is assured.

I with it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

Claims

I claim as my invention:

1. An environmental charging system for providing energy to electric bomb fuzes without the use of external charging equipment, comprising:

a. an electric fuze bomb having an existing charging well common to electrically fuzed bombs and centrally located along the longitudinal portion of the bomb;

b. a proximity sensor connected to said charging well by a multiwire cable and centrally located at the forward portion of the bomb for providing target signals;

c. an electric fuze connected to said charging well by an additional multiwire cable and responsive to said target signals for actuating an explosive mechanism;

d. slipstream actuated energizing means for providing electric energy to said proximity sensor and to said electric fuze in response to a predetermined threshold fluid flow, said slipstream actuated energizer including a resonant cavity for producing fluid oscillations of said input fluid, said energizer being located within said charging well;

e. fluid input means within said energizing means for receiving slipstream fluid flow along said bomb;

f. fluid output means for exhausting a portion of said slipstream fluid;

g. mechanical means responsive to said slipstream fluid flow comprising a diaphragm that vibrates in response to said fluid oscillations and a rod connected to said diaphragm to transmit vibrations to a metallic reed positioned within a magnetic field;

h. a magnetic field coupled with said mechanical means for producing electrical signals in response to said mechanical means; and a magnetic lock means to prevent magnetic field actuation until a preselected minimum air velocity is attained;

i. voltage regulating means for controlling said electrical signal to provide a predetermined voltage output;

j. safety cover means being secured by an O-ring seal and retaining nut to shield said input and output means; and

k. an arming lanyard to remove said safety cover means upon release of said bomb from the aircraft.