US2013656A - Sighting system for guns - Google Patents

Description

Se t. 10, 1935. I J, c KARNES 2,013,656 I SIGHT ING SYSTEM FOR GUNS Filed Jan. 31, 1951 3 Sheets-Sheet 1 k/fl ia f ATTORNEYS. 1

Sept. 10, 935; J. c. KARNES 2,]l3,656

SIGHTING SYSTEM FOR GUNS Filed Jan. 51, 1951 5 Sheets-Sheet 2 imuuml t B h 0 O 1 I 7 {4 N I g k J I Q a? m I f I INVENTOR.

E d. E K arnas TTORNEY Patented Sept. 10, 1935 was . 11 Claims.

(Granted under the act of March 3, 1883, as'

amended April 30, 1928; 370 0. G. 757) 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.

The subject of thisinvention is a sighting system for guns.

Guns designed for firing against aerial. targets are distinguished from guns employed primarily against ground targets by the character of the sighting system, by their weight and degree of mobility, and by their methods of emplacement. The trend .of development in light field artillery guns is tomodify them sufficiently to make it possible for them to engage aerial targets. Alterations directed to this end, however, are not permitted to interfere with such essential characteristics as are specified for a gun whose normal assignment is the ground target.

One of the principal considerations encountered in the design of a dual purpose gun mount is the factor of Weight. The present invention deals with this phase of the problem insofar as it concerns the mechanisms which must be provided to insure the correct laying or pointing of the gun irrespective of the level of the gun mount.

In laying a gun at a moving target it is necessary to give the axis of the gun barrel a position which takes into consideration, in addition to range, vertical and lateral defiection corrections caused by travel of the target during the dead time of loading and the time of flight of the projectile, and also similar corrections to allow for errors caused by reason of elevating the gun on an inclined plane when the gun is transversely and longitudinally out of level due to the nature of its emplacement.

According to the present invention it is proposed to make provision for entering the necessary corrections due to out of level position, solely in the sighting system and to consolidate the values corresponding to the corrections with the principal values of azimuth and elevation.

A practical embodiment of the invention is illustrated in the accompanying drawings, wherein:

Fig. 1 is a more or less diagrammatic illustration in the nature of a View in left side elevation of a gunmount showing the general arrangement of the azimuth component of the sighting system;

Fig. 2 is a similar view of the right or elevation side of the gun mount;

Fig. 3 is a longitudinal sectional view through the sight mount;

Fig. 4 is a transverse sectional view through the sight mount;

. Fig. 5 is a detail sectional view on the line 55 of Fig. 3;

Fig. 6 is a transverse sectional View through 5 the range drum;

Fig. 7 is a view in rear end elevation of the range drum;

Fig. 8 is a detail. sectional view showing the mounting of the pointer on the range drum;

Fig. 9 is a detail sectional View on the line 99 of Fig. 5; and

Fig. 10 is a detail view of the azimuth recorder.

Referring to the drawings by characters of reference:

In Figs. 1 and 2 there are shown the side plates 5 of a gun carriage which is adapted to be rotated about a vertical pivot by a traversing handwheel 6 for the purpose of training the gun in azimuth. A cradle l which is adapted to reciprocally carry the usual gun barrel, is supported by the side plates through the trunnions 8 and rotated by means of the elevating handwheel 9.

Referring to Fig. 4, a support shaft Ill is secured to the left hand trunnion 8 and terminally carries a pin H which constitutes the axis of cross level of the mount and is parallel to the axis of bore of the gun. Mounted on the pin is an annular bearing member 12 embraced by an annular sight mount l3 that is rotatable with respect to the bearing member. The upper portion of the sight mount is formed with a socket I4 for receiving an adapter l5 which supports a telescopic sightinginstrument I6. The adapter is movable with respect to the sight mount by 5 means of the gearing I5a.

The lower portion of the sight mount pivotally carries a Worm wheel sector I1 mounted to slidein a block l8 secured to an arm l9a of a rocker l9 journaled on the support shaft Ill. The block I8 also carries a shaft 20 having a worm 20a in meshwith the sector I! and serving to move the sight mount about the axis of cross level I I. A spirit level 2! placed transversely of the sight mount 13 is provided for indicating the level position of the sight mount.

The rocker l9 carries an arcuate housing 22 in which a segment 23 is slidably mounted. A pointer 24 on the segment is arranged to register with a reference mark 25 on the sight mount IS. A shaft 26 in the housing 22 has a worm 21 meshing with the segment 23 and a worm 28 meshing with a worm wheel on an inclined shaft 29 also mounted in the housing 22. A flexible shaft 30 on the shaft 29 leads to a set of differential geardrum 48.

ing 3| (Fig. 1) into which is introduced a shaft 32 associated with the azimuth mechanism 6 and affording a measure of the azimuth of the gun carriage. transmitted by a shaft 33 to a register 34 where it is interpreted in movement of a pointer 35 (Fig. 10) which is comparable with a second pointer 36 actuated from a remote control station and expressing the value of azimuth from level datum to the position of the target.

Referring to Figs. 3 and 4, the rocker l9 is formed with an arcuate rack 31 meshing with an operating shaft 38 carried in a bracket 39 secured to the side plate 5 of the carriage. This mechanism is provided for the purpose of shifting the sight mount as an entity through a longitudinal angle to compensate for subsidence of the carriage or lack of fore and aft level. In order to indicate when the sight mount is levelled longitudinally there is provided a spirit level 40 on the upper extremity of the rocker I9.

Referring to Figs. 6 and 7 a hollow support shaft 4| secured to the right hand trunnion is formed with an arm 4|a in which is mounted a planet pinion 42. This pinion meshes internally with a drum 43 mounted on the support shaft 4| and normally locked against movement through agear segment 430. which is in mesh With a worm shaft 44 carried in a bracket.45 (Fig. 2) fixed to the side plate.

The pinion 42 is also in mesh with a sun gear 46 on a shaft 4'! mounted within the hollow supthe drum 43 and serving to lock these two members together as well as provide for relative angular displacement.- The band has a laterally projecting finger 53 inscribed with a reference mark 54 readable against the range scale 49 on the drum 48 and it also has a reference pointer 55 readable against a mil scale 56 on the drum 43.

The band also carries a laterally projecting arm 57 terminating in a casing 58 overlying the Journaled in the casing is a drive shaft 59 and a driven shaft 60, the engagement being preferably through worm gearing. A pointer 6! secured to the driven shaft and readable against the range scale 56 is equipped with a transversely disposed spirit level 62. V

The graduations of the range scale are in the form of curves plotted in function of elevation and angle of cross level and varying from concentricity with the pointer 6| by amounts proportionate to the elevation error due to elevating on an inclined plane.

The reference mark 54 and the pointers and 6| are all carried by the band 5| and are displaceable when the band is moved independently of or in conjunction with the drum 43. In order to indicate when the drum 43 is levelled longitudinally it is provided with a spirit level 63 (Fi 7) As shown in Fig. 2 a register 64 is mounted on the side plate of the gun carriage and has a pointer 65 actuated from a remote control station and indicating the value of elevation at which the gun is .to be pointed in direct or indirect firing. p

In practice, a gun carriage when emplaced is seldom level transversely and longitudinally, due

The production of the differential is pointer 6| of the range drum unit is levelled transversely by operating the shaft 59. In these operations spirit levels 2|, 46, 63, and 62 are referred to.

The axis of cross level ll of the sight mount being parallel to the axis of bore of the gun and being movable in elevation with the gun trunnion will indicate the angle of elevation of the gun.

As may be seen from Fig. 4 when the gun carriage is transversely level, the sight mount will be in a true vertical plane perpendicular to the support shaft H) and there will be no effect on the sight mount when the axis of cross level I! is angularly displaced during elevation of the gun.

When the gun carriage is not transversely level, the sight mount upon being cross leveled to position it in a true vertical plane, will no longer be perpendicular to the support shaft l6. As a consequence, angular displacement of the axis of 7 cross level II during elevation of the gun will force the sight mounting to revolve about an axis which is the pivot of the worm wheel sector IT. The sighting instrument carried by the sight mount is thereby automatically deflected an amount equal to the error in azimuth which results by reason of elevating the gun on an inclined plane. The gun is then traversed torelay the sighting instrument on the target or aiming point.

The rocker on being levelled longitudinally angularly displaces the sight mount relative to the support shaft. This has the eifect of entering an elevation angle but is compensated for as will be explained later in connection with the range drum unit. In the case of anti-aircraft firing, the amount of deflection or azimuth error is interpreted by the displacement of the reference mark 25 on the sight mount with respect to the pointer 24 carried by the segment 23. Operation of the inclined shaft 29 to move the pointer 24 into register with the reference mark 25 affords a measure of the lateral deflection correction and is transmitted to the differential 3| for combination with the principal angle of azimuth. The azimuth operator turns the traversing handwheel 6 to keep the pointer 35 matched with the pointer 36 whose position is controlled from a remote station and represents the final value of azimuth based on level datum. V

The elevation component of the error caused by reason of elevating the gun on an inclined plane is compensated for in the curves of the range scale 50. When the pointer 6| is transversely levelled the amount of elevation of the gun and consequent rotation of the drum necessary to register a prescribed range curve with the pointer will be greater as the angle of cross level increases.

The initial adjustment of the range drum unit by longitudinally levelling the drum 43 has the effect of angularly displacing the band 5| carrying the reference mark 54 and the pointer 6| and also displacing the drum 43 as previously explained to place it in the horizontal datum plane. Angle of site displacement is made by moving'the moves on an inclined plane. level 62 has been properly leveled, the rotation band through the shaft 52 to further displace the reference mark 54 and pointer 6!, this displacement being read on scale 56. The amount of rotation of the gun and range scale 5!] in order to register a prescribed range curve for example with the pointer 6| will be greater or less, depending on the angleof site and-the character of the longitudinal inclination of the gun carriage.

The amount of this correction is not required in the sight mounting but because it is represented in the ultimate inclination of the axis of cross level II by virtue of the interdependence of the two gun trunnions, it was necessary to longitudinally level the rocker and displace the sight mount relative to the axis of cross level in order to neutralize the angular displacement of the axis of cross level introduced by operation of the range drum unit.

Since the gun containing the axis of bore is mounted by means of two trunnions it is obvious that all displacements of the trunnions. are reflected in the position of the axis of bore. If the gun is rotated in azimuth while out of level it When the spirit of the gun in azimuth on an inclined plane will soon throw it out of level, so that in consequence, when elevation is to be applied, the pointer 6| must be acted on to restore it to a level position.

Since the azimuth movement includes the correction in azimuth (242229-3I) due to tra versing on an inclined plane, this correction will also be reflected in the resulting elevation error. In view of this there is exceptionally close cooperation between the pointer 24, the traversing mechanism 6 and 3! and the pointer 6|. Con- Versely, if the gun is elevated on an inclined plane there will be an error in elevation and also in azimuth. Elevation through 9 in an amount controlled or indicated by the mechanism of Fig. '7 rotates the trunnion on the left side of the gun and displaces the reference 25 (Fig. 3) to measurably indicate the azimuth error which must be applied through 30 to 3|.

It will be noted that the range scale 49 does not take into account the error in elevation caused by elevating on an inclined plane. Under certain conditions the field artillery disregard this error but if it is desired to take this error into account the gun is laid by employing the scale 50.

All elements of the sighting system may be employed irrespective of the character of employment of the gun. When azimuth and elevation data are not supplied from a remote station and continuously and automatically recorded in the vicinity of the sighting system then these directional values are applied in the customary manner. In firing at a moving ground target, lateral deflection corresponding to the lateral movement of the target may be set in by moving the adapter I5 through the gearing 1511.

I claim:

1. In a sighting system for guns, a carriage, means for traversing the carriage, a register indicating computed azimuth data, means for transmitting the traversing movement to the register for comparison with the computed data, a gun cradle 'trunnioned in the carriage, means for elevating the cradle, a sight mount having an axis of cross level fixed parallel to the gun bore on one of the trunnions, said sight mount being angularly displaceable with respect thereto for longitudinal levelling, means for moving the sight mount about the axis of cross-level, a reference mark on the sight mount, a pointer readable against the reference mark, means for moving the pointer to align it with the mark, means actuated by said moving means and combining'the pointer movement with the traversing movement, means 5 transmitting a measure of such combined movement to the register, a drum carried by the other trunnion, a chart of curves on the drum plotted in function of angle of elevation and angle of crosslevel, a band having a pointer readable against the chart of curves, means for cross-levelling the pointer, and means for angularly displacing the band to level it longitudinally.

2. In a sighting system for guns, a carriage, means for traversing the carriage, a register indicating computed azimuth data, means including a differential for transmitting the traversing movement to the register for comparison with the computed data, a gun cradle trunnioned in the carriage, means for elevating the cradle, a sight 1 the gun is elevated to compensate for the error in l azimuth due to elevating the cradle on an inclined plane, means for measuring such deflection and actuating said diflerential to algebraically combine it with the traversing movement for indication in the register, and means associated with a trunnion for indicating the elevation of the cradle corrected for the error in elevation due to transverse inclination of the carriage.

3. In a sighting system for guns, a carriage, means for traversing the carriage, a register indicating computed azimuth data, means including a differential for transmitting the traversing movement to the register for comparison. with the computed data, a gun cradle trunnioned in the 40 carriage, a bearing member jointed toone of the trunnions for cross-levelling about an axis parallel to the gun bore, a sight mount carried by the bearing member and rotatable thereon in a plane containing or parallel to the axis of cross-level, a rocker on the trunnion, means associated with the rocker and engaging the sight mount for moving the sight about the axis of cross-level, a reference mark on the sight mount, a pointer carried by the rocker, means for moving the pointer into register with the reference mark, and means for transmitting such movement to the difierential for algebraically combining it with the movement of the traversing means.

4. In a sighting system for guns, a carriage, means for traversing the carriage, a gun cradle trunnioned in the carriage, a bearing member jointed to one of the trunnions for cross-levelling about an axis parallel to the gun bore, a si ht mount carried by the bearing member and rotatable thereon in a plane containing or parallel to the axis of cross-level, a rocker on the trunnion, means associated with the rocker and engaging the sight mount for moving the sight in crosslevel, a reference mark on the sight mount, a 5 pointer carried by the rocker, means for moving the pointer into register with the reference mark, and means for algebraically combining a measure of the movement of the traversing means and the pointer.

5. In a sighting system for guns, a carriage, means for traversing the carriage, a register indicating computed azimuth data, means for transmitting the traversing movement to the register for comparison with the computed data, a gun 75 mounted in the carriage for elevation, a crosslevelling sight mount carried by the gun and arranged to be deflected in azimuth due to trunnion tilt as the gun is elevated to compensate for the error in azimuth, and means on the carriage for measuring such deflection and algebraically combining it with the traversing movement for indication in the register.

6. In a sighting system for guns, a carriage, means for traversing the carriage, a gun mounted in the carriage for elevation, a cross-levelling sight mount carried by the gun and arranged to be deflected in azimuth due to trunnion tilt as the gun is elevatedto compensate for the error in azimuth,

, and means for algebraically combining and registering a measure of the traversing movement and the deflection of the sight mount.

7. In a sighting system for guns, a rotatable support, a sight mount carried by the support and rotatable with respect thereto, cross-levelling mechanism for the sight mount arranged to constrain the sight mount to be deflected in azimuth when the support is elevated in an inclined plane, a reference mark on the sight mount, a pointer mounted independently of the sight mount, for movement in an arc and readable against the reference mark, means for moving the pointer to align it with the reference mark and means actuated by said moving means for indicating a measure of such movement.

8. In a sighting. system for guns, a support rotatable in elevation, a range drum carried by the support and rotatable with the support as it moves in elevation, said drum bearing a chart of curves each plotted in coordinates of corrected elevation and angles of cross-level, a pointer movable in cross-level and readable against the chart of curves, means for angularly displacing the pointer about the drum to level it longitudinally, a crosslevelling sight mount rotatable with respect to the'support and arranged to be deflected in:azi-- muth when the support is elevated in an inclined plane, and means carried by the support for angularly displacing the sight mount relative to the support to level it longitudinally. 5

9. In a sighting system 'for guns, a support rotatable in elevation, a range drum carried by the support and rotatable with the support as it moves in elevation, said drum bearing on its periphery a chart of curves each plotted in coordinates of 10 corrected elevation and angles of cross-level, a' pointer movable in cross-level and readable against the chart of curves, and means for angularly displacing the pointer about the drum to level it longitudinally. V

10. In combination, means for computing data for a gun correct for a level platform, a gun, training mechanism for moving the gun,lflr'e control apparatus mounted on the gun giving a corrected value of gun setting, means for algebraical- 20,

1y combining the movements of the training mechanism and the value determined by the firev control apparatus, and a register indicating com-' puted data for comparison with the combined movements of the training mechanism and fire 25;

control apparatus a 11. In agun, means for moving the gun i azimuth, means for elevating the gun, a sight mount, means associating the gun'and mount so that the latter is deflected in azimuth as the gun 30

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