1. Field of the Invention
This invention pertains to riflescopes and more particularly to riflescopes with elevation adjustment knobs.
2. Description of the Related Art
Riflescopes typically include elevation adjustments that enable the shooter to shoot accurately at different target distances by turning the elevation adjustment mounted on the top of the riflescope. When the elevation adjustment is rotated, the riflescope's elevation changes from the scopes zero point. Conventional elevation adjustments on a riflescope have preset ‘click’ values which determine the amount of elevation change when the adjustment is rotated one click or to a predetermined mark on the adjustment. Most elevation adjustment knobs have a click value of ¼, ½, 1 MOA or milrad or some other measurement unit.
The smaller the click value, the greater number of rotations must be made to the elevation adjustment to adjust to different target distances. This can create a slow and confusing situation for the shooter because the dial position must be counted and does not reflect the actual scope adjustment setting, thereby slowing engagement time with the target. If the elevation adjustment has relatively small MOA click values, the total amount of elevation movement per rotation of the adjustment, is limited. When the riflescope has a relatively large click value, the amount of elevation change in one rotation is greater thereby enabling the shooter to quickly adjust the scope for different distances. Unfortunately, riflescopes with relatively large click values can't be finely adjusted at greater distances thus reducing accuracy.
What is needed is a riflescope with a high speed elevation adjustment assembly that allows fast coarse adjustment allowing the shooter to quickly adjust the riflescope for shooting at different distances and also allows the shooter to finely adjust the riflescope for shooting targets at longer distances with maximum accuracy. Having two elevation adjustments, one coarse and one fine, allows for maximum speed without sacrificing accuracy and allows the shooter to return to the zero setting easier than conventional adjustments, even by feel, without visual confirmation of the settings.
These and other objects of the invention are met by the riflescope high speed, coarse and fine adjustment assembly disclosed herein that includes a riflescope with an elongated body that houses an erector tube. Formed on the top surface of the scope body and adjacent to the proximal end of the erector tube is a mounting surface. Formed on the mounting surface is a slotted bore designed to receive the smooth, lower neck of a lead screw that moves up and down through the slotted bore to raise or lower the proximal end of the erector tube.
Disposed over the mounting surface is an adjustment plate with a perpendicularly aligned post member formed thereon. The post member includes a threaded bore designed to connect to the upper threaded neck of the lead screw. In the first embodiment, the adjustment plate is a flex plate affixed along its front edge to the mounting surface. The flex plate includes a flat plate with a transversely aligned groove formed on its lower surface. The groove enables the rear section of the flex plate to bend upward or downward when an upward or downward force is exerted on the rear section of the flex plate. The flex plate is slightly beveled so that when the front section of the flex plate is attached to the mounting surface, the rear section is slightly elevated above the mounting surface. One or more optional springs are disposed between the rear section of the flex plate and the mounting surface to bias the rear section upward.
In a second embodiment, the adjustable plate is a hinge plate pivotally attached to the front edge of a cover plate stacked above the hinge plate. The hinge plate has a flat, thick front section and a rear section with a beveled lower surface. One or more optional springs are disposed between the rear section of the hinge plate and the mounting surface to apply upward pressure to the rear section of the hinge plate.
The lead screw neck is sufficient in overall length to press against the proximal end of the erector tube located inside the scope body when extended through the slotted bore and to extend into the post member. During assembly, the external threads on the upper head of the lead screw are attached to the internal threads inside the post member. When the post member is rotated, the lower end of the lead screw advances or retracts through the slotted bore formed in the mounting surface.
Attached to the top surface of the cover plate is an O-ring seal assembly with a center bore designed to slidingly receive the upper end of the post member. Attached to the rear section of the cover plate is a fine adjustment lever. In one embodiment, the fine adjustment lever is attached to a threaded post that when rotated, extends and presses against a receiving surface formed on the top surface of the adjustable plate. In a second embodiment, the fine adjustment lever is attached to a cylindrical member that extends downward from the adjustment plate. The cylindrical member includes a stepped cam face that contacts a cam follower ball located on the rear section of the adjustment plate.
In both embodiments, the fine adjustment lever is selectively rotated to raise or lower the rear section of the adjustment plate with respect to the cover plate. As the rear edge is moved, a force is exerted on the post member that causes the post member to move to an axially offset position.
Attached to the O-ring seal assembly on the cover plate is a circular detent plate with at least one laterally extending tooth. Attached over the detent plate is a course adjustment dial which includes vertically aligned splines formed on the inside surface that are engaged by the tooth on the detent plate. During operation, the tooth on the detent plate engages the splines on the dial to produce the classic. ‘clicking sound’ commonly heard on riflescopes. In the preferred embodiment, the splines are sufficient in quantity and spaced apart so that one rotation of the coarse dial allows 2 degrees or 120 minutes of travel.
Mounted on the side of the coarse adjustment dial and the windage dial are optional stop tabs that are engaged by a release arm mounted on the cover plate. During use, the tabs and release arm are used to create a zero point for the riflescope. When pressed, the release arm disengages from the stop tabs and allows the coarse elevation dial and the windage dial to rotate freely in either direction beyond the pre-defined zero point. When the coarse elevation dial or the windage dial are rotated back to their original location, the release arm re-engages the stop tabs automatically resetting the original zero point, locking both elevation and windage turrets, thus preventing accidental change to the shooters original zero point.
Referring to the
Disposed over the mounting surface 18 is an adjustment plate with a perpendicularly aligned rotating post member 40 disposed thereover. The post member 40 includes a threaded bore 43 designed to connect to the upper threaded head 52 of the lead screw 50.
In the first embodiment, shown in
The rotating post member 40 includes a top jam nut 42, an upper bearing support 44 and a lower bearing support 48. Located between the upper bearing support 44 and the top surface of the flex plate 20 is an upper bearing 46A. Located between the lower bearing support 48 and the bottom surface of the flex plate 20 is a second bearing 46B. Located longitudinally inside the post member 40 is a lead screw 50 with a threaded upper head 52 that connects to the internal threads 43 formed on the lower bearing support 48. The lead screw 50 includes a lower non-threaded key-shaped neck 54 that extends into a complimentary-shaped slotted bore 19 formed on the mounting surface 18. The slot 19 holds the lead screw 50 in a fixed non-rotating position on the mounting surface 18. The lead screw's neck 54 is sufficient in length to press against the proximal end of the erector tube 16 located inside the scope body 12 after assembly. When the post member 40 is rotated, the lead screw 50 advances or retracts from the slotted bore 19 which causes the proximal end of the erector tube 16 to move up and down inside the scope body 12.
In a second embodiment, shown in
One or more optional springs 60′ are disposed between the rear section of the hinge plate 20′ and the mounting surface 18. The springs 60′ bias and help hold the rear section of the hinge plate 20′ and cam follower ball 28 against the cam face 108 above the recessed surface 18.
Stacked over the flex plate 20 or the hinge plate 20′ is a cover plate 70. Four threaded screws 72 are used to attach the cover plate 70 to the mounting surface 18. The screws 72 extend freely through non-threaded bores 27 formed on the flex plate 20 or hinge plate 20′. The bores 27 are slightly larger than the screws 72 and allow the flex plate 20 or hinge plate 20′ to bend or pivot upward when the fine adjustment lever 100 is rotated.
In both embodiments, an O-ring seal assembly 80 is attached to the top surface of the cover plate 70. The O-ring seal assembly 80 includes a center bore 82 designed to slidingly receive the upper end of post member 40.
Attached to the rear section of the cover plate 70 is a rotating, fine adjustment lever 100. In the first embodiment shown in
Attached to the cover plate 70 is a circular detent plate 110 with one spring 112 that presses against the laterally extending chisel point 114. The chisel point 114 includes a fine tooth 116 located on its distal end. Attached over the detent plate 110 is a coarse dial 120 which includes vertically aligned splines (not shown) formed on its inside surface similar to the splines 144 shown with the windage dial 140. During operation, the chisel point 114 extends outward and engages the splines 144. In the preferred embodiment, the splines 144 are sufficient in quality and spacing so that one rotation of the coarse dial 120 equals 120 minutes.
During use, the coarse dial 120 is rotated for the desired target distance and then the fine adjustment lever 100 is rotated which causes the cam face 108 to be rotated on the cam follower ball 28 thereby pivoting the flex plate 20. The bending movement of the flex plate 20 or the pivoting movement of the hinge plate 20′ finely adjusts the length of the lead screw 50 that extends into the scope body 12. The flex plate 20 or hinge plate 20′ and the lead screw 50 are returned to their original positions by reversing the fine adjustment lever 100 or 100′ and from the pressure exerted by the spring 60 against the mounting surface 18.
With both embodiments, a horizontally aligned lock arm 135 is pivotally attached to the cover plate 70. The lock arm 135 includes a T-shaped tongue member 136 with upward and downward extending tabs 137, 138. The lock arm 135 is pivotally mounted on the cover plate 70 with a lock pin 134. Formed on the outer surface of the course dial 120 and windage dial 140 are two tabs 130 and 142, respectively. During operation, the two stop tabs 130, 142 engage the tabs 137, 138 on the lock arm 135 to prevent rotation and lock the dials 120, 140 at their respective zero points. The lock arm 135 is pressured by a spring 133 and a plunger 132 located at the end opposite the tongue member 136. During operation, the tongue member 136 is pressed inward thereby positioning the tabs 137, 138 below the dials 120, 140. The course dial 120 or windage dial 140 are then free to move from their zero points. When the elevation dial 120 or windage dial 140 are returned to their zero points, the lock arm 135 is released so that the tabs 137, 138 may engage the stop tabs 130, 142 on either dial 120, 140, respectively, to precisely return and hold the two dials 120, 140 at their original zero points.
In compliance with the statute, the invention described herein has been described in language more or less specific as to structural features. It should be understood however, that the invention is not limited to the specific features shown, since the means and construction shown, is comprised only of the preferred embodiments for putting the invention into effect. The invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the amended claims, appropriately interpreted in accordance with the doctrine of equivalents
This is a utility patent application which claims benefit of U.S. Provisional Application No.'s 61/063,265 filed on Jan. 31, 2008 and 61/144,400 filed on Jan. 13, 2009.
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Number | Date | Country | |
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Number | Date | Country | |
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61063265 | Jan 2008 | US | |
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