Abstract:
A precision mount has two split rings that directly engage a telescopic sight. The front split ring is mounted on shoulder bolts to provide a pivoting engagement, while the rear split ring is held within a slide and adjusted vertically therein using a precision adjuster. A balanced lock is provided which ensures alignment is preserved during position locking, subsequent to adjustment. Windage is provided on a separate adjustment between the sight yolk and the rifle attachment, thereby isolating windage from position locking and simplifying the appropriate adjustments. Precision connections are maintained at all critical locations, even after shock or recoil, by using precisely dimensioned pins and mating holes in association with standard bolt fasteners.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. provisional patent application serial No. 60/356,783 filed Feb. 13, 2002 and abandoned herewith. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention pertains generally to sights such as might be used, for exemplary purposes only, in combination with various projectiles and firing devices. In a more specific manifestation, the invention pertains to mounts used on telescopic sights commonly used for very long distance sighting in association with a rifle or the like. 
     2. Description of the Related Art 
     Many years have passed since the first rifles were designed. The original rifles had very little precision, and were equally limited in distance a bullet would travel. With these rifles, the barrel served as an adequate aligning tool. Gradually, new designs permitted riflemen to fire accurately at greater distances, which then led to a need for better ways to align the rifle with an intended target. Early techniques included the use of two small protrusions that extended vertically above the rifle barrel but which formed a common axis with the barrel. These sights were replaced by v-sights still in use today on some modern short-range rifles, where the sight closest to the rifleman&#39;s eye is formed in the shape of the letter “v”, and the forward sight may be an edge or protrusion with a small ball on the top thereof. In practice, the shooter will align the ball or top of the protrusion centered and at the top of the “v”. This type of sighting technique is reasonably accurate to only tens of yards, and then loses too much accuracy to be of any use. Other early sights included the leaf sight, and peep sights where the “V” or “U” is replaced by a closed cylinder, forming a small alignment hole. Commonplace with peep sights are hooded front sights, where a small cover is placed over the front sight to reduce the distortion effect of uneven lighting, such as sunlight from one direction or the other, that might otherwise lead to optical misalignment. 
     As distances increased through improved firing techniques, better bullets and improved barrels, better sights also had to be designed. The telescopic sight, which is essentially a low magnification sighting telescope mounted adjacent the rifle barrel and on an axis roughly parallel thereto, has now become the predominant sight for longer distance shooting. Several benefits are attained, the first which is the additional magnification of the target, which at modem firing distances can be very helpful. A second feature of the telescopic sight in common use today is the elevation and windage adjustment for an internal cross-hair, which permits a shooter to compensate for bullet drop that will occur over distance, in accordance with the laws of physics and gravity, and windage, which is a horizontal or side-to-side adjustment that is made to compensate for drift brought on by a cross-wind. This combination of magnification, internal cross-hairs, and compensation for windage and bullet drop has served the needs of the industry for many years. 
     Greater shooting distances continue to be sought after, and the physical limitations of the telescopic sight prevent this type of sight from fulfilling desired objectives without some further modification or compensation. Several factors must be taken into consideration for a long distance sight. The first is the desired magnification and field of view. In order to increase field of view at a given magnification, it is customary to enlarge optical components. Unfortunately, the size of the sight is limited by physical relation to the rifle, greater manufactured cost of larger components, and also by the weight that larger optical components and all associated necessary structure add: Said another way, a very large telescope is by definition very bulky, very heavy, very expensive, and requires very special mounting hardware to keep the optics in proper alignment after exposure to firing recoil. 
     In order to minimize the expense of the telescopic sight, while still permitting compensation for greater distances than would be attainable with the sight components alone, several artisans have proposed adjustable mounting structures for telescopic sights. These adjustable mounts permit the sight to be used at firing distances greater than can be compensated for with the ordinary bullet drop and windage adjustments available on a traditional sight. Exemplary among these patents are U.S. Pat. No. 1,083,288 to Lowe and U.S. Pat. No. 4,397,107 to Holden, each which are incorporated herein by reference in their entirety for their teachings of sights and mountings and the other more general knowledge of the field presented therein. The Holden patent illustrates an approach wherein a top adjustable setting screw is calibrated to permit bullet drop adjustment with relative precision. An adjustable screw member is designed to protrude within a scope mount and extend downward an adjustable distance. Counteracting this downward force is a spring loaded member that extends from the bottom and side up to the scope tube, while two additional side screws are provided for anchoring the scope horizontally within a split mounting ring. Unfortunately, with the Holden design, the scope housing is supported only by each of the four adjustable screws, which leads to a concentration of force and stress upon very small areas of the telescopic sight tube. Given the substantial recoil that may be endured, especially when firing with long-range bullets, the possibility for damaging the scope either during adjustment or during firing is too great. Furthermore, even small flexures within the scope tube housing will lead to inaccurate distance settings by the rifleman, since the adjustment screw will travel into and flex the scope housing without actually changing the angular orientation of the scope. Finally, in the event of recoil, the telescope tube may move and cause both impact damage and frictional wear to the tube, since the tube is reliant upon support from a spring loaded pin. This design is therefore very restrictive in terms of what size and weight of telescopic sight may be permitted for a given firing load and intended shooting distance. 
     The Lowe patent, which is interestingly of much earlier origin, offers several features that alleviate some of the limitations of Holden. For example, in the Lowe patent, split rings are used to directly clamp about the sighting tube. A secondary framework is provided within which the clamping ring travels. Final position is selected by adjustment with a special thumb wheel and beveled surface, and then the position is locked into place with either a side-mounted screw or a screw and nut combination coming from below the split ring. Unfortunately, using this technique the side mounted screw will tend to pull the sight out of linear alignment with the gun barrel, essentially creating the need for an otherwise unnecessary windage adjustment. Since the Lowe patent provided no convenient way to make such an adjustment, this Lowe design was probably deemed unworkable at the time by other artisans. 
     Since the time of Lowe, there have been numerous additional U.S. patents promulgated that provide two axis adjustment of a sight. These include U.S. Pat. No. 843,183 to Smith; U.S. Pat. No. 1,361,063 to Joeck; U.S. Pat. No. 2,101,037 to O&#39;Neil; U.S. Pat. No. 2,143,167 to Pechar; U.S. Pat. No. 2,165,796 to Humeston; U.S. Pat. No. 2,208,913 to Unertl; U.S. Pat. No. 2,336,107 to Litschert; U.S. Pat. No. 2,491,431 to Unertl et al; U.S. Pat. No. 3,040,433 to Heinzel; U.S. Pat. No. 3,374,544 to Pitchford; and U.S. Pat. No. 3,826,012 to Pachmayr; each which are incorporated herein by reference for their teachings relevant to the art and to the present specification. In spite of the long need and extensive development, there is still a need in this industry for a precision mount that will accommodate existing telescopic sights and extend the useful range thereof. 
     SUMMARY OF THE INVENTION 
     Exemplary embodiments of the present invention solve inadequacies of the prior art by providing a precision mount having two split rings that directly engage a telescopic sight. The front split ring is mounted on shoulder bolts to provide a pivoting engagement, while the rear split ring is held within a slide and adjusted vertically therein. A balanced lock is provided which ensures alignment is preserved during position locking. Windage is provided on a separate adjustment between the sight yolk and the rifle attachment, thereby isolating windage from position locking and simplifying the appropriate adjustments. 
     In a first manifestation, the invention is an adjustable mount for attaching a longitudinally extending sight to a gun barrel. A first pivotal mount affixes the sight at a first location permits rotation relative to the mount. A second adjustable mount generally encompasses and retains the longitudinally extending sight distal to the first location. The second adjustable mount generally encompasses the sight to distribute forces transmitted from gun barrel to sight about a circumference of the sight. A yoke adjacent the second adjustable mount restrains the second adjustable mount against motion perpendicular to an arcuate path extending radially the first pivotal mount and thereby maintains general longitudinal orientation of the longitudinally extending sight. A guide is cooperative with the yoke and second adjustable mount to restrain motion of the second adjustable mount with respect to the yoke to follow the arcuate path radially about said first pivotal mount. A locking fastener has means cooperative with yoke, adjustable mount and guide which operatively locks the second adjustable mount into place relative to the yoke in one of a plurality of angular orientations with respect to the first pivotal mount, and provides balanced forces about the second adjustable mount to maintain longitudinal orientation of the sight during locking. 
     In a second manifestation, the invention is a rifle mount for supporting a telescopic sight upon a barrel having compensation adjustments of vertical angle for bullet drop and horizontal angle for windage that exceed any adjustments available within the telescopic sight. A forward support for the telescopic sight is pivotal about a first horizontal axis and Secured against motion about a vertical axis. A rearward support for the telescopic sight is pivotal about the first horizontal axis and is secured against motion about a vertical axis. A means is provided for accurately measuring an angle of orientation between telescopic sight and rifle barrel. A means is provided that is cooperative with the rearward support for locking the rearward support against motion about the first horizontal axis. A means for supporting the rearward support relative to rifle barrel is pivotal about a vertical axis, and a means is provided for locating the rearward support at a second angle of orientation measured upon a vertical axis between telescopic sight and rifle barrel. 
     In a third manifestation, the invention is a gun mount for mounting a telescopic sight to a gun. The mount has a forward yoke, and a means for pivotal attachment between forward yoke and telescopic sight that is rotatable about an axis compensating for bullet drop. A rearward yoke is rigidly aligned with the forward yoke, and a means is provided for supporting the telescopic sight within the rearward yoke and locking the sight relative thereto. A base has means to anchor rigidly to the gun, and a means is provided to pivot the yokes about the base about an axis compensating for windage. 
     OBJECTS OF THE INVENTION 
     A first object of the invention is to provide a precision telescopic sight mount that will accommodate existing telescopic sights and extend the useful range thereof. A second object of the invention is to isolate windage from elevation position locking. Another object of the present invention is to provide durable means for supporting the telescopic sight that avoids any damage or loss of precision that might otherwise result. A further object of the invention is to ensure precision using existing manufacturing techniques. Yet another object of the present invention is to fulfill the foregoing objectives using available components, where suitable, to benefit from existing volume manufacture and parts availability. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other objects, advantages, and novel features of the present invention can be understood and appreciated by reference to the following detailed description of the invention, taken in conjunction with the accompanying drawings, in which: 
     FIG. 1 illustrates a preferred embodiment telescopic sight mount designed and manufactured in accord with the teachings of the present invention from side plan view with the telescopic sight shown in dashed lines for exemplary purposes. 
     FIG. 2 illustrates the preferred sight mount of FIG. 1 from end plan view, and showing a cut-away of the windage adjustment therein. 
     FIG. 3 illustrates by sectional view along line  3 ′ of FIG. 2 one preferred bolt and pin fastener combination that may preferably be used, or the likeness thereof, at all suitable dimensionally critical connections throughout the preferred embodiment telescopic sight mount. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the most preferred embodiment of the invention, an adjustable mount  100  supports a standard telescopic sight  10 . While the construction, details or features of sight  10 , including the telescopic nature, are not critical to the present invention, sight  10  will typically and most preferably have internal adjustable cross-hairs or similar sighting aids which are adjustable for fine deviations in both of two axes. Typically, a first adjustment  20  will adjust the up and down movement of the sighting aid, while a second adjustment  30  will change the left and right direction. Those skilled in the art of sights will understand that the up-down adjustment  20  is typically used to set a particular distance to a target, to compensate for vertical height lost during the travel of a projectile from the sight to target, while the left-right adjustment  30  is used to compensate for side deviations such as might occur with a cross-wind. The use of this type of sight  10  is not critical to the invention, but is preferred since very fine adjustments are complimentary to the preferred embodiment mount  100 , as will be described herein below. 
     A support bar  110  spans two generally U-shaped vertical yokes  112  and  114 , and also provides an interconnection to a rifle, gun, or other device through base  102  for which a sight of the nature of sight  10  or mount  100  is desired. Vertical yokes  112 ,  114  support sight clamping rings  120  and  130 , respectively. In the preferred embodiment mount  100  illustrated herein, clamping rings  120 ,  130  are each made from two generally semicircular segments that are held together with bolts or similar fasteners. Clamping ring  120  has a lower semicircular segment  127  and an upper semicircular segment  128 , each visible in FIG. 1, while clamping ring  130  has a right semicircular segment  132  visible in FIG.  1 . Each clamping ring  120 ,  130  is most preferably designed to have an inner diameter which is slightly larger than the outer diameter of the sight  10  about which the clamping ring will be affixed, to fit securely thereto without crushing. A slight difference in diameters ensures that clamping rings  120 ,  130  will always be adjustable to be clamped tightly against sight  10 , regardless of small manufacturing tolerances. While this method of attachment is most preferred, it is not critical to the operation of the invention, and other techniques for fastening to telescopic scope  10  may be provided as known in the art. Nevertheless, split rings as illustrated or similar known techniques are preferred to ensure distribution of forces transmitted from the gun barrel to sight during firing, thereby preventing damage or deformation of the sight. This distribution of forces, rather than point forces created by others in the prior art, is important for continued operation of the mount and sight. 
     Clamping ring  120  is adapted to slide within a center of yoke  112 , thereby raising or lowering sight  10 . However, clamping ring  130  only pivots about shoulder bolts  116  with respect to yoke  114 . Therefore, raising or lowering ring  120  with respect to yoke  112  changes the sighting point on a target. Said another way, raising or lowering clamping ring  120  within yoke  112  will change the angle between the axis of scope  10  and the longitudinal axis of support bar  110 . Consequently, a point within the cross-hairs will be shifted higher or lower as a result of the movement of clamping ring  120  within yoke  112 , without changing where the rifle barrel is directed. Those familiar with sighting will recognize that this is the basic goal of an adjustable sight. This adjustment allows a rifleman to change the angle between scope and gun barrel to compensate for changes in distance or air currents between gun and target. Most preferably, yoke  112  will restrain clamping ring  120  to motion only along the arcuate path pivoting about the front clamping ring  130 , and will restrain against motion perpendicular to this arcuate path. Shoulder bolts  116  comprise the preferred embodiment method of providing a pivotal connection between yoke  114  and clamping ring  130 . Nevertheless, other techniques for providing the necessary pivotal motion may be used alternatively, such as precision bearings or the like. Most preferably, the pivotal connection will restrict motion in any direction other than about the pivotal axis. 
     Visible in FIG. 1 are also two small bolts  108  which pass through a plate  113 , through arcuate slots  119  cut in yoke  112 , and into mating holes in clamping ring  120 , where they are secured. The tightening of screws  108  will create force between plate  113  and yoke  112 , thereby locking clamping ring  120  in place with respect to yoke  112 . By using a total of four screws  108 , two on each side of yoke  112 , the careful tightening thereof will keep clamping ring  120  centered, and consequently not affect the windage adjustment described herein below. Other fasteners or fastening means may be provided. An important feature, however, is the provision of balanced forces about the yoke  112  and clamping ring  120  to maintain proper longitudinal orientation of the sight with respect to gun barrel. Arcuate slots  119  may actually be straight or only slightly arced, depending upon the width of the slot and the amount of travel required. The difference in width between arcuate slot  119  and outer thread diameter of screws  108  will provide some tolerance that reduces the amount of arcing required, and which will in some cases eliminate the need for any arcing at all. 
     At the top of yoke  112  is a gauge  150 , which in the preferred embodiment is a very precise instrument such as a long travel micrometer-type gauge or head commonly used on precision measuring instruments. The type of gauge used in the implementation of the preferred embodiment is not critical, and other measuring instruments, either electronic, electromechanical, mechanical, sonic or otherwise will be selected by those skilled in the art after a reading of the present disclosure. FIG. 3 illustrates the internal connection of gauge  150  to yoke  112  and clamping ring  120  by cross-section along line  3 ′ of FIG.  2 . Surrounding a perimeter of gauge  150  are four fasteners  151 ,  152  that pass through plate  158  and into corresponding holes at a top surface of yoke  112 . In order for mount  100  to operate precisely and repetitively, a pair of pins  153  are also provided that pass into mating and precisely fitting holes. This combination of fasteners and pins is used not only to fasten gauge  150  to yoke  112 , but similar combinations of fasteners and pins are used elsewhere. This combination of pins and fasteners provides the benefits of ready self alignment through the pins, precision positioning, and durability to withstand the repeated shocks of bullets or other projectiles being fired. Without the pins, the plates may shift by necessary tolerances between bolts and threaded holes during recoil, which would alter critical alignment and make repeat shots less reproducible. 
     Adapter  154  is used to mount gauge  150  into plate  158  and allow relative adjustment there between, as will be described herein below. In a central region of adapter  154  is an adjustably extended tip  155 , which extends from gauge head  150 . As is known in the industry, gauge  150  may be rotated to extend tip  155  by very small, precise and repeatable amounts. This extended tip  155  will most preferably be used to push clamping ring  120  down relative to plate  158 , thereby precisely controlling the angular orientation of scope  10  with respect to support bar  110 . While tip  155  could be of ordinary softer materials, as could clamping ring  120 , most preferably clamping ring  120  has been provided with a surface  122  having a cylindrical groove  123  therein. Pressed into groove  123  and thereby retained therein is a cylindrical bearing  124  or the like, which preferably extends slightly above the surface  122 . Bearings are preferred, owing to their intrinsic hardness and durability, which coincides with the needs of the present invention. As is known in the field, a rifle or gun recoils. While various weights and devices are commonly provided to reduce the total amount of recoil, there is nevertheless some shock delivered through the firearm and into the mount and sight. A hardened surface prevents this shock from denting or deforming either ring  120  or gauge  150 . Preferably tip  155  and bearing  124  will both be a hard alloy or treated material such as used in the manufacture of bearings. Until screws  108  are tightened down, plate  113  will slide freely up and down along groove  119 . The maximum amount of vertical travel is limited by tip  155 , the length of groove  119 , and the spacing between the end of sight  10  and the rifle barrel. The elevation of yokes  112 ,  114  above support bar  110  can be increased or decreased to allow more or less longitudinal tilt in sight  10 . 
     Under the bottom side of ring  120 , between ring  120  and support bar  110 , springs may optionally be provided which will then compress between ring  120  and yoke  112  and serve to bias ring  120  away from support bar  110 . In the preferred embodiment, no springs are used, and ring  120  will be manually biased prior to locking by tightening screws  108 . 
     In operation, base  102  will be fastened onto a rifle barrel or other device for which precisely adjustable sighting is desired through large distance or elevation deviations. Base  102  may be machined or formed differently than illustrated herein, to accommodate a particular barrel or mounting arrangement. Base  102  will then vary from one application to another, and will typically be designed to accommodate only one or a few select models, such as a particular manufacturer&#39;s rifle, gun or the like. 
     Once mounted to the rifle barrel or the like, shoulder bolts  116  should be sufficiently loose to allow pivoting of clamping ring  130  with respect to yoke  114 . Similarly, bolts  108  are sufficiently loose to allow clamping ring  120  to slide up and down within yoke  112 . With these bolts  108 ,  116  so loosened, the user will press bearing  124  against tip  155 . Adjustment of gauge  150  will raise or lower extendible tip  155  with respect to the end of yoke  112 , thereby raising or lowering clamping ring  120  with respect to support bar  110 . In the preferred embodiment, this adjustment will serve as a potentially large but relatively coarse adjustment. Once this adjustment is made, finer variations, such as are used to change deviation over shorter distances, may be made through the scope up-down adjustment  20 . Most preferably, yokes  112 ,  114  will be held to very tight tolerances, as will clamping rings  120 ,  130 . This allows rings  120 ,  130  to nest tightly into yokes  112 ,  114 , thereby preventing any left and right angular deviation that might otherwise occur. If, as shown in the preferred embodiment, a micrometer gauge is used, an adjustment screw  159  such as shown in FIG. 2 may be provided, which allows gauge  150  to be “sighted in”, or precisely set for a particular angle of elevation or distance of trajectory, ensuring the accuracy of gauge  150 . Adjustment screw  159  in the preferred embodiment illustrated herein interacts with adapter  154  to allow gauge  150  to be rotated, raised or lowered with respect to plate  158 , or to alternatively lock adapter  154  in position relative to plate  158 . 
     In use, a standard telescopic sight will only provide adjustment that allows sighting through distances measured in hundreds of yards or meters. While this is adequate for close range target shooting or hunting, the present invention expands the capability of sighting by providing adjustment through distances that are measured in thousands of yards and even miles or kilometers. To use adjustable mount  100 , the distance between target and rifleman is first determined. Various ballistics tables are available that show the drop of a particular bullet through a particular distance. These tables are used as is known to calculate the angular adjustment required by a sight. If this is greater than the capability of sight  10 , then bolts  108 ,  116  may be loosened, gauge  150  adjusted to set the new angular orientation very precisely, to attempt to zero the sight at the intended distance, and then bolts  108 ,  116  once again tightened. In the event the bullet or projectile passes higher or lower than intended, or varies right to left, final adjustment to the sight may then be made through up-down and left-right adjustments  20 ,  30  already available in telescopic sight  10 . Alternatively, the process of loosening and tightening bolts  108 ,  116  may be repeated. 
     Once elevation compensation is selected for bullet drop compensation, windage may also be adjusted. This may occur either prior to or after bullet drop compensation, owing to the independence of function provided by the present invention. Windage is adjusted through the setting of a second gauge  160  which resembles gauge  150  in both feature and function. An adapter  164  is provided for mounting gauge  160  into support bar  10  and a pin  111  is rigidly anchored into base  102 . The gauge  160  may be adjusted with interaction between tip  165  and pin  111  to accurately set windage. 
     As will now be apparent, gauge  150  may be calibrated to read either in fractions of an inch or millimeters, or may alternatively be calibrated to a specific firearm and bullet to read specifically in target distance. The present invention may therefore be readily adapted through a variety of specific embodiments to accommodate a wide range of sights used with firearms, weapons or other devices in concert with a telescopic scope. Consequently, while the foregoing details what is felt to be the preferred and additional alternative embodiments of the invention, no material limitations to the scope of the claimed invention are intended. The variants that would be possible from a reading of the present disclosure are too many in number for individual listings herein, though they are understood to be included in the present invention. Further, features and design alternatives that would be obvious to one of ordinary skill in the art are considered to be incorporated also. The scope of the invention is set forth and particularly described in the claims herein below.