US2641156A

US2641156A - Automatic flash spotter

Info

Publication number: US2641156A
Application number: US165282A
Authority: US
Inventors: Alfred H Canada
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-05-31
Filing date: 1950-05-31
Publication date: 1953-06-09
Anticipated expiration: 1970-06-09

Description

June 9, 1953 A. H; CANADA ,5

AUTOMATIC FLASH SPOTTER Filed May 31, 1950 QHIFTEQEI: H. Canada Patented June 9, 1953 UNITED STATES PATEN T F F ICE 8 Claims. (01. 88-1) (Granted under Title 35, U. S. Code (1952),

see. 266) The invention described herein may be manufactured and used by or for the Government, for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a flash spotter for use in aiming guns. It frequently happens that in combat at night the gunner of an emplaced gun, while engaged in firing on a particular target, will note the flash from an enemy gun in the same general direction as the target he is engaging but, because of the stress of battle and the tactical situation, be unable at once to fire on the gun whose position was revealed by the flash. Later on, however, when the gunner is free to engage the emplaced gun he may be unable to remember the exact location of the flash and have to wait for another burst from the gun before opening fire.

It is therefore the principal object of this invention to provide a combined gun sight and flash spotter whereby the gun may be trained upon the location of a previously-observed flash, even after the lapse of an appreciable .period of time.

Another object is to provide a flash spotter wherein the spot of light from the flash is projected onto a remembering or light-sensitive surface which surface is angularly stabilized independently of the gun.

A further object is to provide a gun sight wherein a single sight enables the gun to be aimed and at the same time operates to project the flash from the enemy gun upon a .gyroscopically stabilized surface.

Other objects and advantages will be obvious after a study of the following specification inconnection with the accompanying drawing.

In the drawing:

Fig. l is a side elevation of a portion of a rapid fire gun equipped with the invention.

Fig. 2 is a front elevation of the gun and attached sight.

, Fig. 3 is a cross section to an enlarged scale of the combined sight and flash spotter in a plane indicatedby the line 3--3, Fig. 2.

Fig. 4 is a detail elevation, partly in section, ofthe gyroscope and its mounting and spinning means, and

Fig. 5 is a detail plan view of the stabilizing gyroscope and its attached light-sensitive surface as indicated by the'line 5-5, Fig. 3.

Referring in detail to the drawing, l identifies a gun which may be of a rapid fire type hava cradle 2 and barrel 3 mounted for recoil and counterrecoil in and relatively to the cradle.

2 It will be understood that the cradle is mounted upon a gun carriage, not shown, for pivotal movement in train'about a'normally vertical axis and in elevation about a normally horizontal or trunnion axis.

The sight forming the subject of my invention'is identified generally by the numeral 4 and is shown as attached to the side of cradle 2 in position for convenient use by a gunner at the controls oi the gun. The sight comprises a tube 5 having a telescoping section 6 carrying an'eyepiece (not shown) and a rubber eye guard I. A conventional objective 8 and erector 9 are positioned within tube 5. Focussing is affected by moving section 6 axially relatively to tube 5, in a Well-known manner.

A gyro casing I0 is in fixed relation with tube 5 and has a hollow standard or mounting ll fixed to and upstanding from the central portion of its base or'bottom wall lilo. As shown upon Fig. 4 this standard has antifriction bearings l2 journaling the stem portion I30. of a hollow .gimbal frame [3 for pivotal movement about anorma'lly vertical axis. The upper ends .of the yoke portion of. frame [3 fixedly support aligned jet members l4 and I5, each of which forms the terminus of the channel formed by the upwardly-extendingyoke portions. Thus, for example, jet' member i5 forms an extension of channel 15 and is so formed as to direct an air jet downwardly tangential of the rotor ll. Jet member I 4 performs a like function except that its jet is directed tangentially upwardly.

Gimbal ring I8 is journaled on aligned jet members I4 and 15, for pivotal'movement about the normally horizontal axis defined thereby. Rotor I! has an axle I9 integral therewith. The ends of axle l9 are 'journaled in antifriction bearings,not shown, carried by ring l8 whereby the gyro rotor is mounted for spinning about-an axis normalto and concurrent with the axis defined by jet members, l land l5. Rotor I] has pockets 1a for impingement by the jets from members l4 and I5.

Gimbalring I8 has fixed thereto, as by meansof bracket '20, a hollow shell-like element 2,] formed as a portion ofa sphere with its center at the'point of intersection of'the concurrent axes of (1) stem Ba, (2) jet members M and I5, and (3) axle I9. The weightof bracket 20 and element 2| are balanced byan adjustable weight '22 threaded onto a stem 23 having one end fixed in the gimbal ring, preferably, but not necessarily, in alignment with axle I9. When theparts are assembled and properly adjusted and bal- 3 anced, the center of gravity of the rotor l1 and ring I8 and all parts carried thereby, considered as a unit, is at the aforesaid point of intersection. Thus the gyroscope is neutrally mounted with three degrees of freedom and, when spinning acts to angularly stabilize surface 2| despite angular movements of the gun about its train and elevation axes.

As will be noted from Fig. 4, hollow stem |3a communicates with a screened aperture through the bottom wall |a whereby air may be drawn into the casing through jet members 14 and I5, to spin the rotor. Flow of air may be induced by suction within the casing, created by the withdrawal of air therefrom by way of a nipple 24, Fig. 3, having a pipe 25, Fig. 2, leading to any source of suction. In this way, air flows through jet members l4 and I5, thereby forming jets which impinge upon the pockets Ila of rotor I! and spin it at high speed to thereby stabilize element 2|.

Element 2| has its outer or convex surface covered with any one of a large number of wellknown fluorescent or phosphorescent materials such as those disclosed and discussed in U. S. Patent 2,074,226, granted March 16, 1937, or abstract of application Serial Number 667,012, published at 631 O. G. 883, February 21, 1950. Such materials have the property of becoming luminescent under the incidence of ultra-violet,

light, and infra-red rays and of retaining such luminescence for a period of time depending upon the material, examples of which are given in the patent noted.

The telescope or sight includes means operable to project light from a source on or along the line of sight 4 onto the fluorescent surface 2|. This means, as shown, may take the form of a tubular elbow section 26 in communication with and extending downwardly from, tube 5 at the focus of objective 8. The section 26 terminates in a forwardly-directed portion 28a shown as fitting within a short sleeve extending rearwardly from the rear wall of casing l0. Portion 26a mounts a lens 21.

A partial reflector 28 having a reticle formed in its central area is mounted within tube 5 in.

so that the gunner, with his eye at eyepiece 6 is able to view the target in the usual manner.

The spot of light from luminescent surface 2| is a, real image, projected onto partial reflector 28 and appears thereon as a spot of light. As

this spot is at the focus of the eyepiece it is viewable therein the same as though it were a luminous reticle in the focal plane thereof.

In use, with the gyro rotor spinning and there fore acting to stabilize surface 2 I, against angular movement, the gunner aims and fires the gun in the customary way. As he angularly moves the gun in train and elevation, the principal axis of lens 21 angularly moves in a corresponding path over stabilized surface 2|. Should a flash from an enemy gun occur while the gun is aimed in the general direction of the flash, a portion of the light rays therefrom will be reflected by

reflectors

28 and 29 onto surface 2| and cause the luminescent surface thereof to glow at the point or spot of incidence of the rays. This glowing spot will remain for a period of time depending upon the intensity of the flash and the material used in forming the luminescent surface, and its reflection occurs as a spot of light on reflector 28 and is observable by the gunner, whenever the spot is substantially intersected by the principal axis of lens 2'1. When the parts are in such relation, the luminescent spot will be reflected onto the central portion of reflector 28 bearing the aforesaid reticle. Should such a flash occur while the gunner is firing at another target, the invention enables the gunner to again aim at the target which was previously revealed by the flash, simply by aiming the gun until the image of the luminescent spot is again visible on reflector 28 in the same location as when it occurred.

I have thus provided a gun sight which is highly useful under certain conditions of warfare in that a previously-revealed target may be picked up and engaged without waiting for a subsequent revelation thereof. While I have shown a preferred form of the invention, numerous modifications and refinements will be obvious to those skilled in the art after a study of the foregoing disclosure. For example, surface 2| may be stabilized relatively to the gun by mechanical connections therewith such as those disclosed for stabilizing sphere 41 in the application of Edwin H. Ludeman, Serial No.

766,429, filed August 5, 1947, now Patent No. 2,520,943, dated September 5, 1950, for Computing Sight.

such gyro may be used to stabilize surface 2| through suitable follow-up or repeater connections. In another proposed modification for use with emplaced guns, the surface 2| may be aflixed to a horizontal axle which axle carries a pendulous weight in position to hold the surface 2| substantially in the position shown. The axle may be journaled between the arms of a fork or yoke having a vertical shaft journaled in bear.-

ings carried by a standard or support. The end ofthe aforesaid vertical shaft may then be connected to one end of a flexible shaft having its other end fixed with respect to the ground. In such a manner, the light-responsive surface may be maintained in fixed relation with respect to the earth as the gun and its sight, in effect, move angularly thereabout.

The foregoing description should therefore be taken in an illustrative rather than a limiting sense, and it is my desire and intention to reserve all modifications and variations falling within the scope of the subjoined claims.

Having now fully disclosed the invention, what for stabilizing said surface against angular move ment with the gun, and means including a partial reflector in the field of View of said sight for projecting and focussing light rays entering saidj sight onto said surface.

2. The combination with a gun angularly movable about mutually normal train and elevation axes, of a telescopic sight carried. by said gun for angular movement as a unit therewith, said sight including an objective and eyepiece, a gyroscope having a mormtingoonnected with said gun for Also where the gun is mounted I upon a ship or vehicle having a directional gyro,

angular movement as a uint therewith, a portion of a spherical surface having a luminescent surface, a connection between said gyroscope and surface whereby the latter is stabilized against angular movement with the gun, and optical means including a partial reflector angularly positioned across the optical axis of said telescope between said objective and eyepiece, said optical means being effective to project light from a remote point passing through said objective onto said surface whereby to create a luminous spot thereon viewable in said eyepiece when said gun and telescope are directed at said point.

3. In combination with a gun mounted for angular movement in train and elevation, a telescopic sight connected with said gun for angular movement as a unit therewith with its line of sight substantially parallel with the bore of the gun, said sight including ,an eyepiece, a phosphorescent surface, stabilizing means mounted on the gun and connected with said surface to stabilize the same against angular movement with the gun, and means including a partial reflector in the field of view of said telescopic sight for focussing light entering said telescope from a fixed point onto said stabilized phosphorescent surface to thereby create a luminous spot thereon, said last-named means being operable to focus an image of said spot onto said partial reflector for viewing in said eyepiece when said gun and sight are subsequently redirected in the direction of said fixed point.

4. In combination with a gun mounted for angular movement, a telescopic sight for aiming the gun, means connecting said sight and gun for angular movement in synchronism, a threedegree-of-freedom neutrally-mounted gyroscope having a mounting fixed for angular movement as a unit with said gun, a phosphorescent surfac connected with said gyroscope for stabilization thereby against angular movement with the gun and sight, optical means including a partial reflector angularly disposed across the principal axis of said sight for focussing a portion of the light rays entering said telescopic sight onto said phosphorescent surface, whereby, when said gun and sight are aimed in the general direction of a light flash, a luminous spot is created thereby on a portion of said surface, said optical means also operating to focus said luminous spot onto said partial reflector in the field of view of said telescope when said gun is re-aimed in said general direction.

5. In a gun sight, a line-of-sight device, a base, a stabilizing gyroscope neutrally mounted on said base for angular movement about three mutually normal axes concurrent at a point, means connecting said base line-of-sight device for angular movement as a unit, a phosphorescent surface formed as a portion of a sphere, means connecting said surface with said gyroscope concentric of said point for stabilization about all axes transversely of the external line of sight of said device, and optical means including a partial reflector positioned across the line of sight of said device for focussing onto said surface a portion of the external light rays entering said device.

6. In a sight of the kind described, a telescopic sight including a telescope tube having an ob-- jective and an eyepiece therein, a gyro casing fixed with said tube, a gyroscope, means mounting said gyroscope within said casing for universal angular movement about a point, a phosphorescent surface formed as a portion of a sphere, means connecting said surface with the rotor of said gyroscope for stabilization thereby about two mutually-normal axes perpendicular to the line of sight of said tube, a partial reflector in said tube between said objective and eyepiece and at across the axis thereof, and

" means including said objective and partial reflector for focussing a portion of the external light entering said tube onto said phosphorescent surface whereby when said sight is oriented in the general direction of a flash of light, a luminous spot is created thereby on said surface and an image of said spot is viewable on said reflector only when said sight is reoriented in said general direction.

7. A sight as recited in claim 6, said casing being rigidly secured to said telescope tube, said last-named meansincluding an L-shaped tube communicating with said telescope tube contiguone to said partial reflector and having one portion at right angles to, and a second portion par allel with, said telescope tube, a reflector at the junction of said portions and a lens in said second portion.

8. In combination with a gun mounted for an gular movement, a sight carried by said gun for aiming the same and including a partial reflector angularly mounted across the line of sight thereof, a neutral gyroscope carried by said gun for universal pivotal movement with respect thereto, a luminescent surface fixed with said gyroscope for stabilization thereby, and means including said partial reflector to focus light rays enterin said sight onto said surface to produce a luminous spot thereon and to re-focus such spot onto said reflector for viewing in the eyepiece of said sight.

ALFRED H. CANADA.

References Cited in the file of this patent UNITED STATES PATENTS