Abstract:
An aiming system for a trajectory weapon such as a ground launcher, machine gun, mortar, or the like. The aiming system is attached to a conventional mount for the involved weapon. Also disclosed is a method of sighting in a weapon which employs the aiming system.

Description:
CROSS REFERENCE TO A RELATED APPLICATION 
     The present invention is related to provisional application No. 60/119,242 filed Feb. 9, 1999 now abandoned. The benefit of the filing date of the provisional application is claimed. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     In one aspect, the present invention relates to novel, improved aiming systems for trajectory weapons. 
     In another aspect, the present invention relates to novel, improved methods and apparatus for sighting (or zeroing in) weapons. 
     BACKGROUND OF THE INVENTION 
     The present invention is particularly concerned with weapons having a low to high trajectory including, but not limited to, machine guns, grenade launchers, rocket launchers, and mortars. 
     A variety of aiming devices and aiming device mounts have been developed for weapons of the character described above. 
     Zeroing (or sighting) a weapon equipped with conventionally mounted aiming devices typically involves firing the weapon, adjusting the sight, and repeating the firing/adjusting sequence. This process is time consuming, involves live ammunition, and is further disadvantageous in that the whole process has to be repeated each time a weapon is replaced or a barrel is swapped out. 
     Furthermore, conventional aiming devices—such as those available for mortars—are virtually useless in commonly occurring circumstances such as the hours of darkness. 
     Furthermore, in many conventional systems, the aiming device is mounted in a location where it is directly exposed to the recoil generated when the weapon is fired. This can result in the aiming device being moved out of adjustment to the extent that the accuracy of the weapon is significantly degraded. 
     In view of the foregoing, it will be apparent to the reader that there is a need for better aiming systems and better methods for sighting in trajectory weapons. 
     SUMMARY OF THE PRESENT INVENTION 
     These needs are met by the novel aiming systems and sighting in methods and apparatus disclosed herein. 
     The novel aiming systems of the present invention are advantageously designed for use with available and hereafter developed weapon mounts without significant modification of the mount. They are designed to interchangeably accommodate optical, laser, thermal, and other aiming devices as well as combinations of aiming devices. Precise aiming and the capability of achieving first round hits are provided, even under nighttime and other adverse conditions. The precise aiming and first round hit capabilities can be extended to the acquisition of multiple targets. 
     Barrels can be swapped out without disturbing the aiming device(s) that may be in use. This allows a firing mission to be continued without resighting the weapon. 
     As the aiming device systems of the present invention are divorced from the weapon, replacement of a particular weapon with one of a different kind is facilitated. Guide rails capable of supporting a variety of aiming devices are preferably employed, thus facilitating the substitution of one type of sight for another. 
     Interchangeable range scales are preferably employed in the aiming device systems of the present invention. Range scales for a particular type of weapon or ammunition are thereby readily provided. A related advantage of the aiming device mounts disclosed herein is that there is no need to rezero the weapon when switching from one type of ammunition to another; only the selection of the appropriate range scale is required. 
     The range scale is preferably illuminated with a low-level blue to green illumination device. Image intensified night vision devices have low sensitivity in that frequency range. Consequently, the illumination is advantageously the same whether the range scale is viewed with the naked eye or through a night vision device. 
     As mentioned above, a novel method of sighting in a trajectory weapon and the apparatus used in accomplishing this objective are disclosed herein. The sighting apparatus includes a mandrel, which encompasses a laser for projecting a dot onto a target. The mandrel is installed in the muzzle or bore of the weapon with the dot being placed on a target bullseye and the aiming device adjusted until it registers with a second indicator such as a cross-hair. This zeroes the weapon for a selected range, and the range scale on the aiming device mount is employed to select other ranges. 
     Sighting is accomplished easily and quickly and with comparatively inexpensive equipment. The necessity of firing the weapon is eliminated, and the weapon can be sighted with a degree of accuracy that virtually guarantees first round hits. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a weapons mount equipped with an aiming system embodying and constructed in accord with the present invention; 
     FIG. 2 is a second view of the weapons mount and aiming system of FIG. 1; 
     FIG. 3 is a fragment of FIG. 1 to an enlarged scale; FIG. 3 shows the details of two laser type aiming devices which can be employed in the FIG. 1 aiming system; 
     FIG. 4 is a fragment of FIG. 1 drawn to an enlarged scale and showing an arrangement for illuminating a range scale of the aiming system; 
     FIG. 5 is a view showing a heavy barrel machine gun mounted in the FIG. 1 weapons mount, the weapon being aimed in accord with the principles of the present invention to deliver a projectile to a distant target; 
     FIG. 6 is a view similar to FIG. 5 but showing the weapon aimed to deliver a projectile to a closer target; 
     FIG. 7 is a perspective view showing the details of the weapons mount and an arrangement employed to secure the aiming system to the mount; 
     FIG. 8 is a sectional view showing the details of a mechanism employed to lock a sight supporting component of the aiming system in an attitude corresponding to a range selected by the weapon user; 
     FIG. 9 is a view showing the details of a detent system, which facilitates the aiming of the weapon; 
     FIG. 10 shows pictorially how, a weapon is zeroed in according to the principles of the present invention; and 
     FIG. 11 is a front view of a target used in zeroing a weapon by the method described in FIG.  10 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawing, FIG. 1 depicts a conventional, MK-64 weapons mount  20  with a cradle  21  and, supported by the mount, a weapon aiming system  22  embodying and constructed in accord with the principles of the present invention. Weapon mount  20  is conventional except for minor modifications employed in attaching aiming system  22  to the weapon mount. 
     The aiming system includes a stationary support plate  24  fixed to the weapon mount  20 , a sight supporting arm  26  which is pivotable with respect to plate  24 , and a sight supporting rail  28 . An interchangeable range scale  30  is detachably fixed to the rear end  31  of pivotable sight supporting arm  26 , and a knob  32   a  fixed to a shaft  32   b  (see FIG. 8) threaded through adjustment arm  26  and into contact with the support plate  24 . The support plate  24  is provided to lock the pivotable sight supporting arm  26  in a position corresponding to the selected range. (see FIG.  8 ). Detents  33   a  engageable by a spring  33   b  attached to a stationary holder  33   c  (see FIG. 9) allow the gunner to easily find ranges for which detents are provided. The interchangeable range scale  30  allows a weapon supported in mount  20  to be interchanged and allows one to use range scales appropriate for different types of ammunition. 
     The illustrated embodiment of the invention employs two laser targeting-type devices respectively identified by reference characters  34  and  35 . Laser  34  is employed to aim a weapon supported in mount  20  at a target. Laser  35  is employed to illuminate the target or, alternatively, to acquire a second, typically moving target. Knobs  36  and  38  are employed to adjust the azimuth and elevation of the laser devices  34  and  35  when the weapon supported by mount  20  is zeroed in as are internal adjustments (not shown) of the character disclosed in U.S. Pat. No. 5,036,517. 
     Turning now to FIG. 2, aiming system  22  is fixed to mount  20  by a pin  40  and a clamp bracket  42 . These components are also shown in detail in FIG.  7 . 
     Lasers  34  and  35  and the mounting arrangement for those lasers are shown in more detail in FIG.  3 . The particular lasers  34  and  35  shown in the drawing are respectively an IZLID-100p illuminator/designator and an IZLID200p illuminator/designator, both available from B. E. Meyers &amp; Company of Redmond, Wash. 
     It is not required that these two laser type aiming devices be employed, and mounting rail is in fact configured to accommodate other types of aiming devices such as conventional optical sights, thermal imaging devices, etc. 
     Turning now to FIG. 4, range scale  30  is preferably illuminated to facilitate the ranging of the weapon by a gunner. As shown in FIG. 4, a block  44  is fixed to the stationary component  24  of aiming system  22  at the rear end  31  of the stationary component. A U-shaped notch  46  in this plate provides an indicator  48  that is positioned opposite a mark on scale  30  to adjust aiming system  22  to a particular range. Mounted in block  44  at one side of notch  46  is alluded to range scale illuminator  49 . A device capable of providing light in the green to blue range is preferred because the gunner may be employing night vision goggles in periods of darkness. The photomultipliers of night vision goggles are insensitive to light of the color just described. The consequent favorable result is that the level of illumination of range scale  30  will be the same irrespective of whether the scale is viewed through a night vision device or with the naked eye. 
     The 50 caliber heavy barrel machine gun (HBMG) is one of the weapons that weapon mount cradle  21  is designed to accept. This HBMG is identified by reference character  52  in FIG. 5, which shows the barrel  54  of the weapon elevated to fire projectiles at a relatively distant target. FIG. 6 shows the same weapon with barrel  54  depressed to fire projectiles at a closer target. 
     It was pointed out above that one of the significant features of the present invention is a method of bore siting a weapon, such as the illustrated HBMG  52 , with a degree of accuracy which allows for first round hits, an advantage of self-evident importance. Referring now to FIGS. 10 and 11, bore siting is accomplished with: (a) a laser-equipped mandrel  56  installed in the muzzle (or bore)  57  of the weapon being sighted in, such as the illustrated HBMG  52 ; and (b) target  58  which is set up at a distance of 10 meters from mandrel  56 . The elevation and traverse of weapon  52  are adjusted until the beam  60  of energy projected from the laser in mandrel  56  appears as a dot  62  in the circle  64  of target  58 . Lasers  34  and  35  are then adjusted with knobs  36  and  38  and the internal adjustments of the two lasers until the beams  66  and  68  from the two lasers appear as dots on the cross hairs  70  and  72  of target  58 . At that juncture, weapon  52  is zeroed in for first round hits on targets at the range for which target  58  is configured, in this case 800 meters. Range scale  30  can subsequently be employed to target the weapon for other ranges. 
     As will be apparent to the reader, the just-described method for zeroing a weapon has the advantage that the firing of live ammunition is not required. Another significant advantage is that a range of the distance for which the weapon is being sighted is not required. In the exemplary method described above, for example, an area of only a little over 10 meters is needed to sight weapon  52  for a range of 800 meters. In contrast, to sight a weapon for this distance in the conventional manner requires an 800-meter range. 
     It will be apparent to the reader that the invention may be embodied in many forms in addition to those disclosed herein without departing from the spirit or essential characteristics of the invention. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims rather than by the foregoing description and the drawings, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.