Title:
Target seeking aerial bomb
United States Patent 2421085


Abstract:
The present invention relates to projectiles and more particularly to a novel projectile adapted for use as an aerial bomb to be dropped from an aircraft, whereby bombing of a target may be accomplished with much greater accuracy than was possible heretofore. It is known that accuracy in bombing...



Inventors:
Rylsky, Gregory V.
Application Number:
US49437743A
Publication Date:
05/27/1947
Filing Date:
07/12/1943
Assignee:
BENDIX AVIAT CORP
Primary Class:
Other Classes:
244/3.16, 318/480
International Classes:
F41G7/22; G01R31/26
View Patent Images:
US Patent References:
1388932Aerial torpedo1921-08-30
1309500N/A1919-07-08



Foreign References:
GB352035A1931-06-22
FR832427A1938-09-27
IT354768B
IT339479B
IT244797B
GB546488A1942-07-16
FR797933A1936-05-06
Description:

The present invention relates to projectiles and more particularly to a novel projectile adapted for use as an aerial bomb to be dropped from an aircraft, whereby bombing of a target may be accomplished with much greater accuracy than was possible heretofore.

It is known that accuracy in bombing a target from an aircraft is frequently impaired by unavoidable errors in the calculation of dropping angles, and by poor visibility caused by haze, fog or smoke, even when an accurate bombsight is employed. If, therefore, a bomb can be automatically controlled by some suitable means to be guided toward or to seek the target without the necessity of making any calculations or having to see the target, "near misses" can be substantially eliminated or at least reduced to a great extent and bombing of the target carried out very accurately even under extremely unfavorable visibility conditions.

Accordingly, one of the objects of the present invention is to provide a novel projectile adapted for use as an aerial bomb, including novel means automatically controlling said projectile to guide it toward the target, whereby near misses are substantially eliminated or reduced and the accuracy of bombing effectively increased.

Another object is to provide a novel "targetseeking" aerial bomb adapted to be dropped or ejected from an aircraft, including novel means responsive to radiant energy emanating from the target by reflection or direct radiation or otherwise, for automatically controlling said bomb along a path guiding it toward the target, whereby said bomb will hit the target without any further control by the bombardier regardless of the angle at which it may have been dropped or ejected from the bomb rack and/or bomb bay of the aircraft up to 450 or otherwise, as long as it is within the area scanned by the sensitive element of the steering mechanism, or scans the target and reflects the image thereof or the objective lens receives the impact of the radiant energy or light rays.

Another object of the invention is to provide a novel "target-guided" aerial bomb adapted to be dropped from an aircraft into the air, including novel means responsive to radiant spectral energy emanating from the target by reflection, or direct radiation, or otherwise, in the form of invisible heat rays in the infra-red portion of the spectrum, or light rays in the visible portion of the spectrum, whereby the bomb is automatically steered toward the target from the release point by contrast with the value of the heat or light radiation from the target compared with the area surrounding the target.

A further object is to provide a novel bomb including a visible light ray or radiant energy responsive receiving device such as a photo-electric or light sensitive cell or an infra-red ray responsive cell, whereby the received radiant energy may be converted into electrical energy, then amplified and converted into kinetic energy to mechanically and automatically steer the bomb toward an energy radiating target within the range of the receiver.

Another object is to provide a novel image guided bomb including a novel axially positioned image forming and projecting means or quartz lens adapted to intensify the heat or light rays and an image receiving surface that rotates with the bomb on a predetermined frequency cycle in cooperation with a photocell positioned off center or eccentrically of the longitudinal axis of rotation of the bomb at said surface and having a frequency response within said frequency of rotation of the bomb and image receiving surface with or relative to the lens and axis of the bomb so as to periodically or intermittently impinge upon or strike the light or heat sensitive cell, whereby to continuously direct the bomb toward the target under the action of radiant energy or light rays projected to a photo-electric or light sensitive cell, radiant energy receiver or responsive device by the image thereof projected or reflected on the image receiving surface with each rotation of the bomb and a bomb steering device actuated thereby to keep the bomb on a course toward the target.

Another object is to provide a novel bomb adapted to rotate an image receiving surface at a suitable frequency so the locus of the image is concentrically circular with respect to the bomb axis, whereby once in each rotation of the bomb and image receiving surface, the target image, heat or light rays cross the receiving field or mask opening of an eccentrically positioned radiant-energy receiver, photo-electric or light sensitive cell in some part of the said concentric circular image field, in accordance with the frequency response of the photocell or radiant energy receiver, to generate an electric current and energize a steering means.

Another object of the invention is to provide in combination with a novel bomb device a novel means mounted on a photocell or spectral energy receiver responsive to a portion of the infra-red spectrum so shaped that the target image re5s mains on the photocell or spectral energy receiver longer the greater the angle of deflection from the target or the farther the target is from alignment with the longitudinal vertical axis of rotation of the bomb, whereby the bomb steering means is actuated in greater degrees of rotation, deflection or course changing and correcting position toward the bomb axis the farther the bomb is from axial alignment with the target.

The above and other objects and advantages of the present invention will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein two embodiments of the invention are illustrated. It is to be expressely understood, however, that the drawings are for the purpose of illustration only and are not designed as a definition of the limits of the invention; and that when reference is made to a spectral energy receiver, such terminology is intended to include photocells of any type suitable for radiant energy reception, it being the purpose herein to include cells which are responsive to either the light or heat rays and visible or invisible portions of the spectrum.

In the drawings, wherein like reference characters refer to like parts throughout the several views: Figure 1 is a longitudinal cross section view of part of the bomb casing taken so as to expose the relative positions of the elements housed within the nose thereof.

Figure 2 is a plan view of the bomb with the tail portion thereof broken away to show the electro-mechanical rudder operating means.

Figure 3 is a side elevational view of the bomb.

Figure 4 is an elevation view of the nose portion of the bomb, as it appears from the target.

Figure 5 is a transverse section along the line 5-5 of Figure 1.

Figure 6 is a diagrammatic view of the operating circuit.

Figure 7 is a perspective view of a modified form of the invention partly broken away.

Figure 8 is a transverse section taken through line 8-8 of Figure 7 of the bomb casing to illustrate an elevational plan view of a modified form of wing and brake.

Referring to the several figures in detail, numeral 10 designates a regular streamlined bomb casing within the nose or head end 9 of which are mounted the following elements: A spectral energy receiver 11, which may be any type of photocell photo-electric or light sensitive cell, or a cell such as a type responsive to the invisible infra-red ray portion of the spectrum of certain wave lengths or range thereof and containing voltage generating crystals responsive to a gas occluding substance, not shown, hermetically sealed therein; and amplifier 20 of any suitable type; a~d__an.jojective lens 22 which may be of quartzrKrtock salt positioned in an axial opening in the nose or h;ad end of the bomb and communicating with a rearwardly flaring off-center or eccentrical passage 22a angularly through the nose or head portion of the bomb in front of the cell. The objective field of lens 22 is approximately 450 as indicated in Figure 1; other lenses with larger or smaller objectives could Sbe used. For example, an infra-red ray cell may be used such as is illustrated in Patent 2,115,578, issued April 26, 1938, to William M. Hall.

The spectral energy receiver II is eccentrically mounted with respect to the longitudinal axis of casing 10, within the nose 9. The face or window of the receiver II is coincident with the focal plane of the objective lens 22, designated generally as at 12. Fixed over the face of the receiver II in a suitable manner is a mask 15 formed with a triangular shaped aperture 15a, the apex of which extends toward, but falls short of, the longitudinal axis of the casing 10. The sides of aperture 15a are radial with respect to the axis of casing 10, and if extended, would intersect at the axis.

Radiant energy as from a searchlight, or infra red or heat rays emitted from a warm body or reflected therefrom, will be focused by the objective lens 22 onto the focal plane 12. When the radiant energy rays are coincident with the extended line of the longitudinal axis of casing 10, the lens 22 will focus the ray along the longitudinal axis onto the mask 15. The receiver |I will thus remain inoperative.

When the radiant energy emitting body is not coincident with the extended axis of casing 10, the lens 22 will focus the beam onto the window of the receiver II through the aperture 15a in the mask 15. The radial distance from the apex of aperture 15a at which the energy beam is focused by the lens 22 will be determined by the distance the energy radiating body is from the extended axis of the casing 10.

As will hereinafter be described, the casing 10 will be rotated during its free fall. The beam images focused onto the receiver I I will thus sweep across the face thereof and over mask 15 in circular or spiral lines. The time interval during which receiver 1 is activated will be the same in each case regardless of the radial distance from the aperture apex. In Figure 5, the spiral dashed line 16 indicates the locus of the path of a focused energy beam; the outer loops indicating the target emitting the radiant energy beam was just within the range of the missile, that is, within the objective field of the lens 22, while the inner loops show the radiant energy beam coming into coincidence with the extended axis of the casing, indicating that the missile had directed itself toward the target.

Mounted in the tail portion of casing 10 in circuit with cables 18 and 19 leading from amplifier 20 are the steering or rudder operating elements, which include a solenoid 23 and a rudder 25 or forwardly extending arm thereof forming an armature adapted to be shifted to and from an outer stop 24, by said solenoid 23 in response to the amplified signals generated from the infra-red radiant energy or photocell or by a suitable photocell or the voltage generating means above referred to of spectral energy re65 ceiver I1.

The rudder 25 is pivotally mounted in the tail of the bomb casing 10 on a pivot member 26, in such a way that deflection about the pivot 26 takes place from the neutral position to one side only.

The axis of rotation of the rudder 25 is fixed approximately ninety (90) degrees to the line of symmetry of the opening 15a in mask 15 on spectral energy receiver I, shown in Figures 1 and 5; so that the steering impulse given to the rudder will always deflect the bomb, so as to displace the focused target image closer to the longitudinal axis of the bomb casing 10. Slight deviation from the 90' angle between rudder 25 and the line of symmetry of the cell 11 may be provided as needed to compensate for lag in rudder movements and lag in aerodynamic response of the bomb.

When the target image has shifted to and is in line with the longitudinal axis of the bomb as indicated at X, no exposure is made through mask 15, no activation of the spectral energy receiver II occurs and rudder 25 stays in neutral position. This means that the bomb is in line with the target. When the bomb gets out of line with the target, the above process is repeated until it is again restored to the correct position.

The bomb casing 10 is provided with wings 27.

The wings are pitched and extend outwardly from said casing in different planes, approximately at right angles to the plane of the rudder 25. The bomb will be rotated about its longitudinal axis by the eccentric wings during its free fall. The rate of rotation of the missile will be determined by the pitch of the wing surfaces. The rotational velocity of the bomb must be equal to or less than the response frequency of the energy receiver 11.

During its free fall, the bomb casing 10 will rotate with it the lens 22, the mask 15, and the receiver II. The energy beam picked up by the lens 22 will be focused on the mask 15 and the receiver II in the spiral pattern shown by the line 16 in Figure 5. When the rate of rotation of the missile is equal to or less than the response frequency of the receiver, the solenoid 23 will be energized once during each revolution of the missile. When the rate of rotation is greater than the receiver response frequency, the impact of the energy beam on the receiver may occur when the receiver has only partially recovered from a previous activation. The solenoid 23 will thus be energized at irregular intervals, causing an erratic and unpredictable course of the bomb.

Due to the time lag between the instant the receiver 11 is activated by an energy beam, the operation of the solenoid, and the change in course due to rudder operation, the nose 9 of the missile is rotatable with respect to the casing 10.

The mask 15 and the receiver II may thus be rotated with respect to the plane of the rudder to compensate for this time lag. The degree of compensation may be set with respect to a scale 29 on casing 10.

In operation, the bomb in falling will rotate about its longitudinal axis due to the wing construction hereinbefore described. The lens 22 will focus onto the plane 12 any radiant energy beams within the 45° angle objective field as indicated in Figure 1. As the focused beam sweeps across the aperture in the mask 15, the receiver 11 will be activated. The signal is amplified by the amplifier 20 and then energizes the solenoid 23. The rudder 25 will then be moved counterclockwise (Figure 2) to steer the bomb.

Since the axis of the rudder 25 is approximately at right angles to the line of symmetry of the aperture 15a, the movement of the rudder will direct the missile toward the target when the focused beam activates the receiver 11. (See Figures 2 and 5.) Figures 7 and 8 illustrate a modified form of the present invention insofar as the means for rotation and means for regulation of the velocity of rotation are concerned.

Numeral 30 designates an annular wing or propeller construction comprising a plurality of suitably pitched propeller blades 31. The annular wing 30 is positioned about the bomb casing 10 at a point most likely to offset "yawing" of the bomb in flight and each blade 31 is pitched to impart limited mean velocity rotation, such velocity of rotation being substantially limited to a frequency cycle within the frequency receiving or responsive cycle of any suitable photocell or spectral energy receiver used. Swiveled or pivoted between annular rings 32 and 33 of wing 30, on pivots 28 and 34 are feathering "spoilers" or centrifugal retarder members, such as feathering brakes 35 and 36.

Brakes 35 and 36 are normally in a retracted non-braking idle position within the wing 30, until the velocity of rotation of bomb casing 10 and its related parts exceeds or approaches the limit of the frequency response cycle of the suitSable type photocell or spectral energy receiver being used.

When the velocity becomes too high, brakes 35 and 36 swing out against the action of retainer or biasing springs 37 and 38, tethered to partitions 39 and 40, by pins '41 and 42 and serve to retard rotation of the missile.

As the operation and construction of the modified form illustrated in Figures 7 and 8 are otherwise the same as the form illustrated in Figures S1 through 6, no further reference to the modification is necessary.

There is thus provided a novel target seeking bomb that may be used for any type target and one that is effective to eliminate near misses and particularly against sea craft, such as warships, which represent considerable contrast in the value of heat radiation compared with the surrounding water and/or any other large targets on land or sea. Also, as pointed out in the specification and claims, in addition to operation from comparative heat wave radiations, radiant energy or light rays, the illumination of the target by a search light and utilization of the reflected visible light may be similarly converted into electromotive force to guide the bomb, when any suitable type light sensitive cell may be used which is responsive to such visible energy waves.

While only two embodiments of the invention have been illustrated and described, various changes and modifications, which will now appear to those skilled in the art, may be made without departing from the scope of the invention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What is claimed is: 1. A target seeking missile comprising, a casing having a nose portion and a tail portion, an objective lens in said nose portion concentric with the longitudinal axis of said casing, a spectral energy receiver in said nose portion in the focal plane of said lens and disposed eccentrically with respect to the axis of said casing for receiving the spectral rays focused by said lens radiated from a target toward which the missile is launched; means for rotating said missile about its longitudinal axis in its flight toward the target, whereby the focused spectral rays periodically traverse said receiver to activate the same; and guide means at the tail portion of said missile operative upon activation of said receiver to direct said missile at the target radiating spectral energy rays.

2. A target seeking missile comprising, a casing having a nose portion and a steering rudder on the tail portion; an objective lens in said nose portion concentric with the longitudinal axis of said casing, a spectral energy receiver in said nose portion in the focal plane of said lens and disposed eccentrically with respect to the axis of said casing for receiving the spectral rays focused by said lens radiated from a target toward which the missile is launched, a mask for said receiver having a triangular aperture therein, the line of symmetry of said aperture being substantially at right angles to the plane of said steering rudder, means for rotating said missile about its longitudinal axis in its flight toward the target whereby the focused spectral rays periodically traverse the aperture in said mask to activate said receiver, and means operative upon activation of said receiver to operate said rudder to direct said missile at the target radiating spectral energy rays.

3. A target seeking missile comprising, a casing having a nose portion and a steering rudder on the tail portion thereof; an objective lens in said nose portion concentric with the longitudinal axis of said casing, a spectral energy receiver in said nose portion in the focal plane of said lens and disposed eccentrically with respect to the axis of said casing for receiving the spectral rays focused by said lens radiated from a target toward which the missile is launched, a mask for said receiver having a triangular aperture therein, the apex of said aperture extending toward, but falling short of the longitudinal axis of said casing; the line of symmetry of said aperture being substantially at right angles to the plane of said steering rudder, wing members secured to said casing for restrictively rotating said missile in its flight about its longitudinal axis, the rotational velocity of said missile being within the limits of response frequency of said receiver, whereby the focused spectral rays periodically traverse the aperture in said mask to activate said receiver, and means operative upon the activation of said receiver to operate said rudder to direct said missile at the target radiating spectral energy rays.

4. A target seeking missile comprising, a casing having a nose portion and a tail portion; an objective lens in said nose portion concentric with the longitudinal axis of said casing, a spectral energy receiver in said nose portion in the focal plane of said lens and disposed eccentically with respect to the axis of said casing for receiving the spectral rays focused by said lens radiated from a target toward which the missile is launched; means for rotating said missile about its longitudinal axis in its flight toward the target, whereby the focused spectral rays periodically traverse said receiver to activate the same; centrifugally operated spoilers fixed to said casing to limit the rotational velocity of the missile in its flight within the limits of response freREFERENCES CITED 35 The following references are of record in the file of this patent: UNITED STATES PATENTS Number 40 1,309,500 1,388,932 Number 45 352,035 832,427 354,768 339,479 244,797 50 546,488 797,933 Name Date Wildrick ------------ July 8, 1919 Centervall ---------- Aug. 30, 1921 FOREIGN PATENTS Country Date Great Britain ------ June 22, 1931 France ------------- July 4, 1938 Italy --------------- Dec. 7, 1937 Italy -------------- Apr. 22, 1936 Italy ---------- - Feb. 18, 1926 Great Britain------- July 16, 1942 France ------------- Feb. 24, 1936 quency of said receiver, and guide means at the tail portion of said missile operative upon activation of said receiver to direct said missile at the target radiating spectral energy rays.

5. A target seeking missile comprising, a casing having a nose portion and a steering rudder on the tail portion thereof; an objective lens in said nose portion concentric with the longitudinal axis of said casing, a spectral energy receiver in said nose portion in the focal plane of said lens and disposed eccentrically with respect to the axis of said casing for receiving the spectral rays focused by said lens radiated from a target toward which the missile is launched, a mask for said receiver having a triangular aperture therein, the apex of said aperture extending toward, but falling short of the longitudinal axis of said casing; the line of symmetry of said aperture being substantially at right angles to the plane of said steering rudder, wing members secured to said casing for rotating said missile in its flight about its longitudinal axis, centrifugally operated spoilers fixed to said casing to maintain the rotational velocity of said missile within the limits of response frequency of said receiver, whereby the focused spectral rays periodically traverse the aperture in said mask to activate said receiver, and means operative upon the activation of said receiver to operate said rudder to direct said missile at the target radiating spectral energy rays.

GREGORY V. RYLSKY.