US1935615A

US1935615A - Automatically deflected gun sight

Info

Publication number: US1935615A
Application number: US351897A
Authority: US
Inventors: Richard C Coupland
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-04-02
Filing date: 1929-04-02
Publication date: 1933-11-21
Anticipated expiration: 1950-11-21

Description

NO V. 21, 1933. Rgc, COUPLAND 1,935,615

AUTMATICALLY DEFLECTED GUN SIGl-KIT Filed .April 2, 1929 3 Sheets-Sheet 1 d fawn:

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'Rthard [flulgnland Nov. 21, 1933. R c, couPLAND AUTOMATIGALLY DEFLEFGTED GUN SIGHT Filed'April 2, 1929 s sheets4sheet 2 gru/venten Richard E- England MM @M atten m q Nov. 21, 1933. R Q CUPLAND 1,935,615

AUTQMATICALLY DEFLECTED GUN SIGH'T Filed April 2, 1929 3 Sheets-sheet :s

Richard E- Etprland vPatented Nov. 2l,

wagersI appiicaaonlamu 2, 1929. serial No. 351,5897

einser the aus @e n s, ists, as @naar apar so, 192s; si@ o. o. 757) The invention described herein may be manufactured and used by or for the Goverment for governmental purposes, without the paymentsto me of any royalty thereon. i

5 This invention relates to variable speed mechanism and is particularly designed for hre control apparatus\ employed under conditions where either or both the gun or bomb platform and target are moving at high speeds.

Where a gun and target are relatively movable,

the directing of the gun must take into consideration a horizontal and vertical lead which are determined by the relative angular travel as inuenced by the velocity and trajectory' of the projectile, conversely this will be true for a sighting device in bombing' from aircraft except for the vertical control.

i The object of this invention is the provision of a nre control apparatus in which members interpreting the rate of the relative angular travel in both the horizontal and vertical -planes are associated with a constant speed device to prof duce a variable speed mechanism displacing the line of sight of the aiming device to correct for the future position of the target or otherwise to indicate the lead.

With the foregoing and other objects in view, the invention resides in the novel arrangement `and combination of parts and in the details of ,construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed twithout departing from the spirit of the invenion.

\ A practical embodiment of the invention is illustrated in the accompanying drawings, where- Fig. 1 is a view in side elevation of the improved mechanism as applied to the sighting system of a' gun;

Fig. 2 is a plan view thereof; Fig. 3 is a sectional viewtaken on the line 3-3 of Fig. 1; 4

Fig.4'is an enlarged longitudinal sectional view through the rate mechanism;

Fig. 5 is aplan view of Fig. 4; Fig..6 is an enlarged detail view o! the pawl; and Figs. I and are detail views of diierent forms of sights.

Broadly, the invention consists in the provision of a series of slides movable at a predetermined rate of speed and means for moving the slides successivelyin predetermined proportion to the rate oi.' angular movement oi' a givenobject, thus giving a measure of the angular movement of such object in a given period of time.

The invention is illustrated as directly applied to a gun 5 mounted by means of trunnions 6 in a top carriage 7 which is rotatably supported 60 on a base 8.

Referring to Fig. 3, the' re control apparatus consists essentially ofsimilar rate mechanisms, one designated at A being horizontally positioned for association through actuating mechanism B with the top carriage 'l and the ,other designated at C being vertically positioned for association through actuating mechanism D (see Fig. 1) with the gun trunnions 6. Accordingly, the mechanism A deals with the relative angular travel or position of the target in azimuth and the mechanism C functions in a similar capacity with regard to elevation. The term elevation as used herein refers to both plus and minus elevation, that is, .elevation above the horizontal and depression below the horizontal.

The rate mechanisms A and C are disposed out of line in a housing E so that they may be more conveniently driven by, a constant speed motor F of any suitable character. As seen in Figs. land 3, the driving shaft 9 from the motor F meshes with a pair of gears 10 and 11, the former fast on the shaft of the vertical mechanism C and the latter connected to the axis of the horizontal mechanism A through the shaft 12 and gear- 85 ing 13. f

As the rate mechanisms aresubstantially alike, only one will be described in detail. Referring especially to Figs'. 4 and 5 the driven axis 14 of the mechanism is in the form of a shaft on 80 which is secured a drum or cylinder 15, in-the 'present instance these members being formed integrally. A plurality of similar slide racks 18 conveniently arranged about the periphery of the drum are mounted for longitudinal movement 95 parallel to the axis by means of tongues 17 (see Fig.\ 5) on opposite ends of eachrack tting ih grooves 18 in the vThe grooves are se rated centrally of the drum by a diaphragm 18 which forms a seat for a pair of springs 20-20 l0 conijined by the tongues 1'1.

For the purpose of adjusting the springs 20 to properly position the slides 16 there may be provided adjusting screws 17a threaded in tongues 17 which are drilled and tapped for this purpose. 1(

The actuating mechanism B consists of a shaft, in this instance having a flexible portion, geared through the usual traversing pinion (not shown) with e ring gear (not shown) on the base 8 $9 that movement of a top carriage when travers- 1I ing the gun will cause rotation of the shaft. The actuating mechanism D in this instance consists of a train of gears actuated through movement of the gun in elevation.

Slidably mounted in the shaft 14 is a rod 21 to which the longitudinal displacement of the individual racks 16 -is constantly communicated. Inasmuch as this displacement may be in opposite directions, the connection with the rod 21 is established through aA bridge 22, one end of which embraces and is secured to the rod and the other end is slidably mounted on the axis 14. The ends of the bridge confine springs 23-23 whose inner ends are seated on pressure plates 24-24, one at each end of the drum and extending over all of the racks.

The actuating mechanism B or D includes a pinion 25, mounted in position to mesh with the racks. The rate at which this pinion is rotated is controlled by the movement of the gun, telescope or other instrument in following the target, vertically or laterally, and affords a measure of the relative rate of angular travel of the target.

In order that a rack 16 when displaced by the pinion 25 may be held in displaced position when disengaged from the pinion while the pinion is acting on the succeeding rack, there is provided a pawl 26 (see Figs. 5 and 6) carried in a fixed member such as the housing E and positioned at a predetermined' distance from the pinion, preferably slightly less vthan the width of one rack 16 and in position to mesh with the racks 16 on the revolving drum. The pawl 26 may be rigidly mounted but is preferably held in a balanced or neutral position by opposite springs 27 which have sufficiently greater strength than the springs 20 to insure retention of the rack 16 in the displaced position so long as the pawl is in engagement therewith. f

The pawls 26 in this instancehave' teeth which mesh with the teeth of the slides 16 so that a slide 16 is held by the pawl in the position which it has when brought into contact with the pawl until the slide is again moved out of engagement with such pawl.

In direct re the lead angle, which must be given the gun to compensate for the speed factor is applied by deviating the line of sight with respect to the axes of direction of the gun. Within limited ranges where the error resulting from reduction in muzzle velocity is negligible and permissible because of the dispersion of the cone of the trajectory of the bullets, the measure of angular rate as determined during the observing interval may be utilized to directly establish the amount of lead to be applied to the gun. For a known muzzle velocity and sight base the movement imparted to the rod 21 to correctly represent the lead for a. definite "rate is determined by proportioning the width of the racks 16 and the speed of themctor F.

In accordance with the foregoing a rod 28 on which is a rear sight 29 is associated with the vertically movable rod 21 of the rate mechanism C, being y:mounted in a guide 30 thereon so as to be/,capable of horizontal movement through an arm 31`f`secured to the bridge 22-of the rate mechanism A. The lateral and vertical displacement of the rear sight produced by the rate mech-lv Similar to the favorable application of the device for firing at limited ranges will be its adaptation for bombing at low altitudes where the'acceleration of the bomb may be neglected because of the member dropped or the size of the target.

When the problem of determining the vertical lead corresponding to greater ranges or altitudes is undertaken, consideration must be given to the trajectory of the projectile and the effect thereon of the angle of departure. In conformity with standard practice 'a grid sight 32 (see Fig. 8) may be employed in lieu of the sight 29. In this sight the horizontal wires are calculated to give proper tangent corrections for horizontal i'lre at the ranges marked on the sight. This sight when used as a front sight is customarily suspended as a pendulum to automatically reduce the maximum horizontal correction by the proper amount as the angle of departure increases until ihe correction reaches zero when the angle of departure is 90 or perpendicular. 'Ihe movability of thefront sight is inherently unsatisfactory because of its tendency to oscillate and it is, therefore, possible to introduce the angle of elevation correction into the movement of the rear sight by including in the actuating mechanism D a pair of driving

members

33 and 34 whichv are calculated to vary the movement of the pinion 25 an'd the rear sight 29, in accordance with the change in the angle of elevation.

f The effect of range on the lateral deflection may be introduced into the actuating mechanism B by inserting therein a differential gearing 35 which will result in obtaining the product of the rate by the time of ight corresponding to range.

The sight may also be in the form of a bar 36 (see Fig. 7) whose stem 37 may be carried by the rod 21 of the vertical rate mechanism C and rotated through connection with the bridge 22 of the horizontal rate mechanism A.

In the angular travel method of fire control,

as applied to bomb sights and anti-aircraft directing apparatus, the vertical and lateral corrections are determined by measuring the angular travels during a unit of time and multiplying this factor by the time of flight. Electrical devices for interpreting the rproblem are unsuited for field service because of their delicate construction and because they are influenced by climatic conditions. Mechanical devices invariablyemployed are variable speed mechanisms of the disk and roller 'type having interposed balls. The friction drive-communicated by the balls gives rise to considerable lost motion and the data obtained cannot, therefore, be accurate. Distinguished from the foregoing the rate mechanism of the present invention being provided with a positive drive will aftord precise measurements orindications of the angular rate of travel for application in an integrating device.

The operation of the device is as follows: the motor F is running' at a predetermined rate of speed/thereby rotating the rate mechanisms or drums A and C at la known rate. While the gun or other movable object 5 remains stationary the slides 16fretain their normal position and the line of Sight remains in parallelism with the longitudinal axis of the gun or other movable object 5. If, however, the object 5 is moved in elevation the gear 34, by reason of its meshing with the stationary gear 33, will rotate causing rotation of the train of gears D and through the pinion 25 moving a slide 16. vThis movement of the' slide \16`will be a measure of the angular @movement of the object 5 during the time that aecomo f; inemesh with the pinion 25. Movement of a slide 16 causes movement of the bridge 22 through movement of a plate 2t and consequent unbalancing ot the springs 23-23. This movement of the bridge 22 is imparted through shaft or rod 21 to the bue 30 in which the `sight stem 28 is carried, thus moving the sight 29 and throwing the line of sight out of parallelism with the longitudinal axis of the object 5. As the slide 15 p from contact, by reason of the revolution of the drum C. with the pinion 25, it comes into contact with a pawl 26 by which' it is held in its altered position until the next slide is passing from contact with the pinion 25.

From the foregoing it will be clear that the device operates to give a measure oi the angular movement of an object in a given period of time and that by properly proportioning the gearing through which the slides 16 are moved this movement, in directing gun re, may be made to automatically set in the lead angle made necessary by reason of speed oi the target. It is also evident that by developing the gears 33? and 3d from the curves of relation between superelevation and quadrant elevation the slides may be made to move so as 'to properly set the sights to automatically correct for superelevation.

anismAisthesameasthatoutlinediorthe mechanism C except that in this case the pinion 25 is driven through shaft B which is rotated through the usual traversing pinion (not shown) fast on the lower end of such shaft and with the ring gear (not shown) on the base 8. This gearing is so proportionedas to give a move= ment to the slides proportional to lateral deection. When desired to take account of the eect of range on lateral deection a dierentlal 35 may be inserted in the shaft B Iand operated in wir' well-known manner to secure a movement ci the pinion 25 which will be a measure of the product oi the rate by the time of iiight correspondlng .to range.

I claimt' In combination with a member mounted for `movementl in traverse and elevation, a vertical rate mechanism operable upon movement in elevation of the member, a horizontal rate mechanism operable upon traverse of the member, each of said rate mechanisms including a drum series of gear-driven slides mounted on said drum to `slide axially thereof in either direction from a f normal position, a member displaceable by said slides, a sight mounted on the displaceable member of the vertical mechanism, and means connecting said horizontal mechanism with the sight e for denecting the latter in a horizontal piane. In traversing the gun the action of the mech- RICHARD C. COUPLAND.