US 2569010 A
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Sept. 25, 1951 F. v. KUZMITZ ET AL 2,569,010
GUN SIGHT Filed Jan. 2, 1945 a Sheets-Sheet 1 FRANK KuzM/Tz BENJAMIN J. Sour/4 MSW ATTOkNEY Sept. 25, 1951 F. v. KUZMITZ ET AL GUN SIGHT 6 Sheets-Sheet 2 Filed Jan. 2, 1943 uwszvwzes FRANK \l. KuzM/Tz BENJAMIN J. SOUTH ATI'OPNEY 6 Sheets-Sheet INVENTOES Sept. 25, 1951 F. v. KUZMITZ ET AL GUN SIGHT Filed Jan. 2, 1943 F/PANK V KuzM/Tz BENJAMIN J. SouTH ATTORNEY Sept. 25 1951 F. v. KUZM lTZ ET AL GUN SIGHT- Filed Jan. 2, 1945 6 Sheets-Sheet 5 /I t I f f 5 140 v f I 4 uvvewrozas O FRANK V KUZMIT'Z l BENJAMIN J. SOUTH b1 HEW ATTORAEY P 1951 F. v. KUZMITZ ET AL 2,569,010
' GUN SIGHT Filed Jan. 2, 1943 6 Sheets-Sheet 6 INVENTORS FPANK V KuzM/Tz BENJAMIN J. SOUTH BY M 9% ATTORNEY Patented Sept. 25, 1951 GUN SIGHT Frank V. Kuzmitz and Benjamin J. South, South Bend, 11111., assignors to Bendix Aviation Corporation, South Bend, 1nd,, a corporation of Delaware Application January 2, 1943, Serial No. 471,124
This invention relates to gun turrets and particularly to turrets of the type which may be used in aircraft. More particularly, the invention relates to improvements in sighting means for turrets of the type where the gunner occupies a fixed station with respect to the aircraft, and sights upon a target by means of a sight which moves with the guns in all positions of elevation and azimuth.
It is an object of this invention to provide a turret having therein novel sighting means which will produce an erect image to the gunner for all positions of the turret in azimuth.
Another object is to provide a sighting mechanism for a turret which will be synchronized with the movement of the guns of said turret for all positions in azimuth and elevation.
A still further object comprehends the provision of novel means for indicating to the gunner the position of the guns of said turret in azimuth.
Yet another object of the invention includes a novel signaling arrangement for indicating to the turret gunner the position of enemy targets both in azimuth and elevation.
A further object comprehends the provision of novel means both for indicating the position in azimuth of the turret guns and for indicating the position in azimuth of an enemy target.
The foregoing and other objects of the invention will be apparent from the drawings and the description hereinafter following, which form a part of this specification. It is to be understood, however, that the embodiment described is merely a preferred one, other embodiments made according to designers choice falling within the spirit of the invention being distinctly reserved, the scope of the invention being determined only by the claims which are hereto subjoined.
In the drawings forming a part of this specification:
Figure l is a substantially side view of an aircraft carrying a bottom, retractable turret having incorporated therein the improvements forming a part of this invention;
Figure 2 is an enlarged sectional view of the aircraft shown in Figure 1 in the vicinity of the turret, showing the turret in an extended or working position, and being under the control 0 a gunner;
Figure 3 is an isometric, diagrammatic view of the turret in an extended position, showing the power means for controlling the movements thereof in both azimuth and elevation;
Figure 4 is a substantially side view of the turret in a plane normal to the axis of elevation 2 rotation of the guns shown in Figure 3, showing in some detail certain of the parts thereof, and showing certain details of the sight forming a part of this invention;
Figure 5 is a detailed longitudinal section of the sight shown in Figures 1, 2, and 4;
Figure 6 is transverse section of the sight shown in Figure 5 taken along the lines 66;
Figure 7 is a schematic, isometric, view of the sight shown in Figure 5, the parts thereof being arranged according to the position they occupy when the turret has rotated to azimuth position; and
Figure 8 is a wiring diagram showing the circuit for controlling the indicator system shown in Figures 5 and 6.
Referring now to Figure 1 of the drawings, the new and improved turret forming a part of this invention is shown as a bottom, retractable type turret I00 mounted in such a manner that it is substantially flush with a fuselage I02 of an aircraft I04, thereby imposing very little drag on the aircraft I04 when in the retracted or non-operating position. A novel sight I06, forming a part .of this invention, is shown with its objective end protruding but slightly from the bottom surface of the turret I00.
Reference is made to Figure 2. to show the turret I00 in an extended or working position, wherein a gunner I08 kneels on a cushion ll 0, his chest being supported on a rest H2 attached to the turret I00. As shown, the gunner I08 is peering through the eyepiece I50 of the sight I05, and is also controlling the movement of the turret I00 and the guns thereof in azimuth and elevation by manipulating with his right hand a single control H4. In Pontius et a1. application Serial No. 438,602, filed April 11, 1942, now Patent No. 2,404,090 granted July 16, 1946 there is described and claimed a suitable form gun turret power control, although other forms may also be used if desired.
Guns H6 are mounted in the turret I00, and for providing a recess for the guns I I6 when the turret 00 is retracted a pair of gun wells :IIB are provided in the fuselage I02.
The mechanical and electrical parts relating to the turret I00 are shown diagrammatically in Figure '3, and as shown, the turret I00 is supported on a four arm spider which is secured to structural members such as at I22 of the aircraft I00, and which has rotatably mounted at the center thereof a column #24 adapted to move axially with respect to the spider I20 for retracting and extending movement of the turret I00, and adapted also to rotate with respect thereto for azimuth movement of the turret I00.
A head unit I26 mounted on the upper end of the column I24 is adapted to rotate with respect to the column I24 and to move longitudinally therewith according to the retracting or extending movement of the turret I00. However, head unit I26 is restrained from rotative movement with respect to the spider I20 by a telescoping yoke member I28 secured at its inner end to the head unit I26 and at its outer end to an extreme end of the spider I20. Head unit I26 is also adapted to hold against rotative'movement the eyepiece I50 of the sight I06, which is not shown in Figure 3.
For moving the guns H6 in azimuth and for retracting the turret I a single power source I30 is provided which acts through an appropriate gearing system as shown to rotate a ring gear I32 which has an internally threaded portion for cooperating with the threaded portion of the column I24. Movement in azimuth of the guns H6 is effected by means of a key I34 which engages both the ring gear I32 and the column I24, as is described and claimed with particularity in Pontius et al. application Serial No. 407,468, filed August 19, 1941, now Patent No. 2,389,991 granted November 27, 1945. v For effecting the movement in elevation of the guns II6 there is mounted at the lower end of the column I24 a rotatable shaft I36 which has secured at each end thereof gun I I6. The power means for moving the guns in elevation includes a motor I38, which operates through the gear train shown.
For gathering in the field of view of the sight I06 shown in Figures 1, 2, 4, 5, 6 and 7, a field scanning piece or prism I40 is provided which is proved sight forming a part of this invention is shown in Figure 5. The sight I06 comprises two cylindrical tube portions I58 and I60 which are coaxial with the axis of the center column I24 and which are adapted to rotate with respect to each other. The upper portion I58 is held against rotation by an integral flange I62 extending therefrom which is secured to the head piece I26. The lower cylindrical portion I60 is adapted to rotate with the guns II6 as they sweep in azimuth.
The loweror objective end of the sight I06 is supported by the lower cylindrical tube portion I60, which also carries at its lower end the housing I52 for enclosing the field scanning piece or prism I40. The glass window I66 forms synchronized in its movements with the movepiece is correctly positioned for any position of the guns in elevation and azimuth.
Referring now to Figure 4, there is shown with more detail the placement of the sight I06 with respect to the center column I24 of the turret I 00. The sight extends above the head piece I26 and terminates at its upper end in the rest I made of sponge rubber or the like for the gunner I08. The sight I06 extends below and beyond the lower end of the column I24, and is provided at the lower end thereof with a housing I52 for the field scanning piece I40 and for an objective lens system (not shown in Figure 4). The objective face of the housing I52 is provided with a glass window I66 (shown in Figure 5) which can be kept free of ice or rain by an automatic wiper arrangement I54 driven by appropriate means.
Means are provided for giving an illuminated reference pattern for sighting purposes to the gunner. As shown generally at I56 in Figure 4, the means includes a lamp housing having a lamp therein whose rays'impinge against a reticle to give a desired light pattern. Reference will be had to Figure 5 for the details of construction of the reference pattern illuminating means I56.
The details of the optical system of the im-V a sighting or objective face for the sight I06, and it is kept free from moisture and ice by the wiper I54.
The field scanning piece I 40 is 'journalled as at I 68 in the housing I52, and is adapted to be rotated as the guns I I6 move in elevation by means of the rack I46 and the pinion I48. It may be noted that for a given angle of change in elevation position of the guns II6, the angle of rotation of scanning prism I46 is one-half because the angle through which the reflected ray is moved must equal the angle of elevation movement of the guns.
An objective lens system I10 is provided for focusing the light received from the field of view upon an image plane I1Ii from the principal plane P1-P1 of the objective system I10. The image formed on the image plane I1I1 is then transmitted upwardly past a fractionally illuminized mirror I12 disposed at 45 to the axis of the sight I06. The fractionally illuminized mirror I12 is of the type which can reflect an image formed on its upper surface, and which can transmit substantially unchanged and through itself any light which impinges upon its under side.
For transmitting to the eye of the gunner I08 a reference or aiming point, a lamp housing I14 of the illuminating reference means I56 is provided which supports a lamp I16 mounted therein whose rays pass a reticle I18, forming a light pattern of any desired shape which is reflected from the mirror I12, upwardly. to a principal plane P2-P2 of the objective side of an erecting system comprising lenses I80, a dove or doubleright prism I90, and 'a similar group of lenses I 92.
A second aiming pattern may be provided in the upper flat surface of the uppermost lens of the objective lens system I10, and may be in the form of a circle or a cross etched or ground into said lens.
As has been explained above, when the guns are moved in azimuth the ordinary perisc'ope, or sight, which would give an erect image for the straight aft or 0 azimuth position to the gunner, whose position is fixed with respect to the 1 airplane, would give images which are no longer erect as viewed by the gunner for positions other than 0 azimuth, that is, when the guns are pointed other than straight aft. Accordingly, to provide means to give an erect image to the gunner for whatever position in azimuth his 5. angle in azimuth to which the guns .IIG are turned, and with the double group of lenses-I80 and I92 always erects the target image so that it always appears vertical and so that right and left are properly oriented to the gunner.
For moving the dove prism I90 to the half angle position there is provided on the upper end of the cylindrical portion 150a beveled ring gear I82 which engages aplurality of pinions I84 which are carried in a mounting. I86, which also supports the dove prism, I90. Carried by the upper cylindrical portion I58, which, as has been explained before, is secured against rotation by being fastened to the head unit I26 by means of the flange I62, is a second beveled rin gear I88 which similarly engages the pinions t84. Since the lower cylindrical portion rotates with the turret in azimuth, and as the upper cylindrical member I58 is held against rotation, by a suitable selected gear ratio, the prism I90 will rotate at one-half the angular speed of the guns H6.
The image formed on the image plane Ii-I1 is thus transmitted through the erecting system, comprising lens group I80, dove prism I90 and lens group I92, and is then passed on, where it once more forms on an eyepieceimage plane Iz-Iz properly oriented for all positions of, the guns H6 in azimuth. Thence the rays forming the image on image plane I2-I2 is viewed by a suitable eyepiece lens system I94.
Secured in a housing I95 which lies intermediate the eyepiece or rest I50 andthe flange I62 are a plurality of indicator lamps, F2 and A2 of which are shown in Figure 5. Referring to Figure 6, which is a section taken along the lines 6-6 in Figure 5, there is shown all of the indicator lamps for signalling to the gunner both the position of the guns H6 in azimuth and the direction in both azimuth and elevation of an enemy target. Lamps A2, L2, F2, and R2 may be white in color and are adapted to light bull's-eyes I96 and are adapted also to transmit light rays to the inner ends of radially disposed plastic members I98, so that regardless of whether the gunner has his eye at the eyerest I50or not, he is always apprised of the octant position of the gun H6.
The circuit for controlling the lighting of the gun position indicator lamps A2, La, F2, and Rs will be described later with reference to Figures 3 and 8. y
Also secured in the housing I94 is a similar set of indicator lamps A4, L4, F4, andR-i which may be colored red to indicate the direction inboth azimuth and elevation of an enemy target and which are adapted to light the bull's-eyes I96 attendant upon each of the lamps. Similarly, plastic rods, bent to the proper shape,- carry the light rays furnished by the indicator lamps to the interior of the sight I06. Thus it will be. seen that the gunner may know of the position of an enemy target when his eye is fixed to the eyepiece I50, and also when he is at rest. The circuit for controlling the lighting of signal lamps A4, L4, F4, and R4 will be. described with respect to Figure 8.
Referring now to Figure '7, there is shown a schematic partly isometric View of the sight I 06 shown in Figure 5, the parts of the optical system of the sight I06 being arranged according to the position they occupy when the turret has rotated to the 90 azimuth position. I
For the sake of clarity part of the boundary rays only forming the image transmitted by the sight I06 are shown and are labelled vt, b, l and r,
6. indicating respectively the top. bottom, lett and right boundary rays 01 the image.
Asshown in Figure I, the field scanning piece I40 has moved to the azimuth position, and the dove prism I90 has moved to the half-angle position, or through 45. The rest of the optical system has not changed position, except insofar as the objective system I10 and the pair of lenses I00 has rotated with the lower end of the sight through 90 azimuth.
The path taken by the top ray, t, will now be described to show how the sight I06 will keep erect the image seen by the gunner even though the turret has moved in azimuth. Similarly, the erection of the image for other positions in azimuth could be shown, the 90 azimuth position of the turret being selected only for simplifying the discussion of theerecting function of the sight I06. Top ray t enters the field gathering piece or prism I40 at its objective face whence it is refracted and then reflected from the oblique face of the prism I40 to the upper surface of said prism. There ray t is once more refracted to enter the objective lens system I10 and to pass therethrough. Ray t similarly passes through the lowest part of the erecting system I80, I90, and I92 until it is refracted at the lower oblique race of the dove prism I90, being reflected from the back vertical face of said prism to the upper I oblique surface of prism I90. Ray t is refracted once more at the upper oblique face and passes through the uppermost part I92 of the erecting system I80, I90, and I92, whence it is passed through the eyepiece lens system I94, emerging to be seen as the top part of the image seen by the gunner I08, who, as has been explained, occupies a fixed position with respect to the aircraft I04. Similarly, the left of the image will always appear to be in its proper position as viewed by the gunner; so, also, will be the right and the bottom of the image. Thus, it will be seen that the image of a sighted target will appear always to the gunner to be erect and properly oriented right and left.
The circuit for effecting the signalling to the gunner both the position of his guns in azimuth and the direction of an enemy target both in azimuth and elevation is shown with reference to Figure 8. The circuit shown consists of two parts, one of which is controlled by an observer, and the other of which is controlled by the position of the guns in azimuth.
A source of power for the circuit is furnished by an inverter 300 which supplies alternating current at a desired voltage and frequency which may he stepped down to a desired operating value by a transformer 302, the secondary of which may be tapped in the manner shown to obtain anydesired voltage.
The gunners station is indicated generally in Figure 8 and shows a lower bank of lights F2, R2, A2, and L: which light according to the position of a wafer switch 304 mounted on an extension 306 of the azimuth drive shaft of the turret shown in Figure 3. The designations A, F, L and R represent the aft, forward, left and right positions respectively of the guns or target with respect to the observer. As shown in Figure 3 the wafer switch 304 is closed on switch point A1, since the guns H6 are pointing in the straight aft or 0 azimuth position. However, in Figure 8 the guns H6 of Figure 3 are pointing to a position between straight aft and to the left, left being to the observersleft and not to the gun- 7 ners left, since the 'gunner needsionly to know the direction according to a signal, and not according to his orientation with the aircraft.
Current is supplied from the secondary of the transformer 302 through a lead K to the wafer switch 304 where the current is picked off at switch points A1 and L1 and passed through leads M and I respectively to illuminate signals A2 and L2 respectively, which, in Figure 8 are shown as signal lamps similar to those shown in Figures 5 and 6. Thus, since signal'lanips A2 and L2 are lighted, indication is given to the gunner that his guns are pointed somewhere in the quadrant between 0 azimuth and 90 azimuth, or between the straight aft position as would be viewed by the gunner, and the straight left position as viewed by the observer.
Similarly, when the guns I I6 rotate in azimuth, for example to the 180 azimuth position, or straightforward, the wafer switch 304 ,willcontact a similar switch point F1. At such time, current will be supplied by the lead K to the switch 304; thence it is picked off at switch point F1 and passed through lead H, thereby lighting lamp F2. It may be noted, that as the wafer switch 304 revolves with the turret in azimuth the flow of current supplied by lead K is vmade and broken at switch points A1, L1, F1, and R1 to light and to extinguish the corresponding signal lamps A2, L2, F2, and-R2.
For indicating to the gunner the position of an enemy target in azimuth, a series of switches located at the observers station is connected into the circuit shown in Figure 8. As vwas the case in supplying energy to the signalling system for indicating the position of the guns in azimuth to the gunner, the transformer 302 through its secondary supplies current to a similar lead N. At the observers station there is located a series of switches F3, R3, A3, L3. According to the position of the enemy target, that is whether it is straight aft as viewed by the observer or straight ahead;
the observer will close switch A4 or switch F3. Similarly, if the target is to the right of the aircraft, the observer will close switch R3, and if to the left of the aircraft as viewed by the observer, he will close switch L3. Provision is made also for signalling to the gunner the position of an enemy target when it occupies intermediate positions, as for example, midway between the straight aft position and the straight left position, or as related to the orientation of the turret I00, between 0 azimuth position and the 90 azimuth position. At such time the observer will close switches A3 and L3 thereby lighting the proper signal lamps.
The circuits foraccomplishing the signalling to the gunner the direction in azimuth of an enemy target is as follows: Assuming that the target occupies a position between 90 elevation and 135 elevation, the observer will close a switch 308 to a right hand switch point 3I0. Assuming also that the target is coming from the straight aft position he will close switch A3. Current will then flow from the lead N, through the switch A3, and thence through a lead P to light signallamp A4. The current passes through signal lamp A4, and thence through a common lead Q to ground through the right hand switch point 3I0 of the switch 308.
Assuming now for example, that the target aircraft is approaching the ship from some direction between 0 azimuth and 90 azimuth, the observer will close switches A3 and L3, and if the enemy target is approaching from some position between As has been explained with reference to Fi zenith and elevation the switch 308 will be kept closed upon the switch point 3I0. At such time, current will be passed from the lead N through the switch A: and switch L3, to pass current respectively through leads P and S to signal lamps A4 and L4. It will be apparent, therefore, that for other positions in azimuth of the enemy target the observer can close an appropriate switch, or an appropriate pair of switches and through the medium of signal lamps F4, R4, A4, L4, give the approximate position in azimuth and zenith of an oncoming target ship to the unner.
For indicating to the gunner that the target which is approaching from a direction below the 135 elevation angle, the observer can close a left hand switch point 3I2 of the switch 308. By so doing an auxiliary source of control current is brought into use to effect an intermittent lighting of the signal lamps F4, R4, A4, L4, to indicate the approximate direction in both elevation and azimuth of the target ship. The circuit for controlling an intermittent energization of the signal lamps comprises a source of power 3I4 which is connected through a switch 3H3 to a lead J, which supplies current to a slow release relay 3I8, which when energized serves to attract an armature 320 to the right to close on point 322 which forms part of a circuit in parallel with the circuit for lighting the lamps F4, etc. Thus, when switch 308 is closed upon the left hand switch point 3I2, the current supplying any one or a pair of lamps F4, R4, A4, L4 will be intermittent in character; so, when slow release relay 3I8 is energized the armature 320 will be attracted to the right, thereby supplying a ground for the return lead Q through the switch 322 to the left hand switch point 3I2 of switch 308. But, when the armature 320 is attracted to the right the circuit for energizing the relay 3 I 8 will be opened, thereby causing the condenser of the relay 3I8 to unload its charge into the winding of the relay 3I8, and when the flux is dissipated in the winding of relay 3I8, the armature 320 will no longer be attracted to the right. At such time, the current for the return lead Q will be broken, since it is no longer made at the switch point 322 of the armature 320. It will be seen, therefore, that the lamps will glow intermittently according to the energization and deenergization of the relay 3 l8, and will indicate to the gunner the direction in azimuth and elevation below the 135 zenith of a target ship.
The operation of the improved turret and sight will be readily understood from the foregoing description. The gunner I08 occupies the position shown in Figure 2 which shows the turret I00 extended to the working position, and with his right hand grasps th control handle II 4, which when rotated away from the gunner causes the guns H6 to rotate about shaft I36 downwardly, the power being furnished by elevation drive motor I38 shown in Figure 3 which is controlled by control I I4. By rotating the handle toward himself the gunner moves the guns upwardly in elevation. The sam control II4 effects, through the azimuth drive motor I30 shown in Figure 3, the azimuth movement of the guns By moving the control handle II4 about its vertical axis away from himself the guns IIB are moved to the right in azimuth, and conversely, by moving the handle II4 about its vertical axis towards himself the guns are moved to the left in azimuth.
ures 5, 6, and 7, when the guns are moved in azimuth and elevation, the sight I06 is also correlated with said movements, so that th aiming point of the guns H6 will be seen by the gunner I08 through the sight I06, and the image of the aiming point will always appear erect and properly oriented right and left.
When the observer sees an enemy target he can signal to the gunner I08 its direction in azimuth and elevation so that the gunner may imimediately train his guns on the target. According to the position of the target ship he closes switches F3, R3, A3, L3, and switch 3l2 shown in Figure 8 to light the corresponding signal lamps mounted near the eyepiece I50 of the sight I06 shown in Figures 5 and 6. The gunner, being always apprised of the position of his guns in azimuth by the signal lamps F2, R2, A2, and L2 can then immediately move th guns I I6 to the position to keep within the field of view of sight I06 the enemy target.
The operation just described is accomplished with a minimum of delay, a factor quite important in present-day aerial warfare. An aircraft, particularly a bomber, equipped with the new and improved turret described hereinbefore is thus made more completely protected against enemy aircraft, and is thus able to carry on a mission without the necessity for a fighter escort, a very desirable advantage, since bombing mission are carried on over distances far beyond the range of fighter planes.
While the present invention has been described with reference to it use in a modern bombertype aircraft, its use is not limited to aircraft alone, other uses, for example, in tanks being possible. The invention, then, is not limited to the embodiment shown, nor otherwise than by the appended claims.
1. In combination with a gun turret mounting guns movable in unison in azimuth and elevation, a sighting mechanism carried by said turret and including a stationary eye piece and a view piece movable simultaneously with the guns and having a field of view embracing the field of fire of said guns for viewing a target on which the guns are laid, means for indicating to a gunner peering into the eye piece the position of said guns in azimuth with respect to said gunner comprising an electrical system including signal de- Vices located in the eye piece housing, and a switch in said electrical system constructed and arranged to be actuated as the guns move in azimuth to control said signal devices.
2. In combination with a gun turret mounting guns movable in unison in azimuth and elevation, a sighting mechanism carried by said turret and including an eye piece fixed relative to the turret and a View piece movable simultaneously with the guns and having a field of view embracing the field of fire of said guns for viewing a target on which the guns are laid, means for indicating to a gunner peering into th eye piece the position of said guns in azimuth with respect to said gunner comprising an electrical system including signal devices located in the eye piece housing, a switch in said electrical system constructed and arranged to be actuated as the guns move in azimuth to control said signal devices, and means for visibly determining the position of the target with respect to the gunner comprising a device positioned in the eye piece housing, whereby to obtain position relationship between the gun and target.
3. In combination with a gun turret mounting guns movable in azimuth, a sighting mechanism including an eye piece housing having an eye piece therein and a view piece for viewing a target, said view piece being movable with respect to the eye piece and constructed and arranged to follow the movement of the guns, a set of signal lights in the eye piece housing for indicating to a gunner peering into the eye piece the position of the guns in azimuth with respect to said gunner, and means including a switch constituted to be actuated by movement of the guns in azimuth to control said signal lights.
4. In combination with a gun turret mounting guns movable in azimuth and elevation, a sighting mechanism including an eye piece housing having an eye piece therein and a view piece for viewing a target, said view piece being movable with respect to the eye piece and constructed and arranged to follow the movement of the guns, a set of signal lights in the eye piece housing for indicating to a gunner peering into the eye piece the position of the guns in azimuth with respect to said gunner, means including a switch constituted to be actuated by movement of the guns in azimuth to control said signal lights, a set of signal lights in the eye piece housing for indicating to said gunner peering into the eye piece the position of the target in azimuth and elevation with respect to said gunner, whereby the relative position between the gun and target is shown by the signal lights, and means including operator operated switches to be actuated by an operator to control said last-named set of signal lights.
FRANK V. KUZMITZ. BENJAMIN J. SOUTH.
REFERENCES CITED The following references are of record in the file of this patent:
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