Not Applicable
Not Applicable
Not Applicable
1. Field of the Invention
This invention relates to the field of telescopic sights for firearms. More specifically, the invention comprises a detachable mount for a telescopic sight that can be detached using one hand without adjusting the customary grip on the firearm.
2. Description of the Related Art
Detachable mounts for telescopic sights have been in use for approximately one century, owing to a long-recognized need. Firearms, particularly sporting rifles, are relatively durable items capable of withstanding wide variations in atmospheric conditions and substantial physical shock. Telescopic sights, in contrast, are relatively delicate optical instruments. Although their design has been advanced considerably in recent decades, telescopic sights remain vulnerable to variations in atmospheric conditions and to physical shock. A sharp blow to a telescopic sight will often shift its point of aim. Worse, there is no visual indicator of this shift, meaning that the user is often unaware of the shift until a shot is fired and missed.
As a result of these factors, hunting rifles with permanently attached telescopic sights must be treated delicately. It has therefore long been recognized that the ability to detach the telescopic sight until it is needed is highly desirable. One such type of detachable mount is disclosed in U.S. Pat. No. 5,035,487 to Herz (1991). While effective, the Herz type of device is slow to operate. The user must hold the rifle securely while using his or her free hand to rotate the small levers employed to engage the scope mounts. These levers do not provide much mechanical advantage. Both must be rotated independently to the correct position. The telescopic sight must then be lifted off without tilting—or the device tends to become stuck.
In hunting situations, the telescopic sight must often be removed rapidly. This is particularly true when following up wounded game. In such close range work, the use of the open (sometimes called “iron”) sights on the rifle is generally preferred. Thus, a scope which could be removed quickly using a single latching device is preferable.
The Herz device also incorporates the interaction of camming surfaces generating high surface friction. There is no accommodation for wear compensation. Thus, as the device is used over time, the interlocking surfaces tend to wear loose—eventually rendering the device inoperable.
One type of detachable mount using a single latching device is known as the “European claw.” This type of mount dates back to approximately World War 1. Printed sources within the art sometimes refer to this type of mount as a “Suhler” mount. Though the Applicant is unable to verify the origins of this name, one would assume that “Suhler” refers to the individual who originally created the design.
The Suhler mount is relevant to the consideration of the present invention. As the Applicant is unable to discover a prior patent disclosing the details of the Suhler design, the Applicant is submitting the details herewith.
In preparation to installing the Suhler mounts, dovetail cut 44 is milled into receiver ring 22. Front Suhler base 46 is then press-fit laterally into front dovetail cut 44. In some instances, it may also be soldered in place. The reader will observe that the upper planar surface of front Suhler base 46 opens into two front Suhler slots 50.
Rear Suhler base 48 is installed on receiver bridge 24 in one of two ways. Some receiver bridges have an upstanding lug into which a lateral dovetail cut can be made. If this is the case, then rear Suhler base 48 is press fit into place (and possibly soldered) in the same fashion as for front Suhler base 46. Other receiver bridges have only a rounded cylindrical surface that is too thin to accommodate a dovetail cut. In that case, rear Suhler base 48 is soldered onto the top of the receiver bridge in an operation obviously requiring considerable skill and precision. Rear Suhler base 48 has a pair of rear Suhler slots 52.
At the time the Suhler design was created the object was to mount old scope sight 56.
Still referring to
Front ring 58 has two descending front Suhler lugs 62. The forward facing surfaces of these two lugs are angled to form mating surfaces 66.
Suhler slider 54 is biased—typically by springs—to move forward (right to left in the view as shown). Returning briefly to
Returning now to
The spring bias forcing Suhler slider 54 forward therefore locates the device securely along the axis of the rifle's barrel. The interaction of Suhler slider 54 and mating notches 68 limits the vertical motion of rear ring 60. The interaction of mating surfaces 66 with corresponding surfaces in front Suhler base 46 limits the vertical motion of front ring 58. The lateral fit between the four descending lugs and the four slots in the Suhler bases limit any lateral motion. Thus, the telescopic sight is locked securely in place.
Installation of the device is basically the reverse of the process just described. The user starts by placing front Suhler lugs 62 in front Suhler base 46. The user then pulls back on Suhler slider 54 (using the tabs), which allows rear Suhler lugs 64 to drop into rear Suhler base 48. The user then releases the tabs, allowing the device to engage and lock. It should be noted that some rear Suhler lugs 64 incorporate a beveled lower surface which automatically moves Suhler slider 54 rearward when the rear of old scope mount 56 is pressed down firmly (thereby eliminating the need for the user to grasp the tabs to attach the scope). This variation is actually the one illustrated.
In
The Suhler mount suffers from a second inherent drawback. Not only have modern scope sights grown larger, they are also considerably heavier than old scope sight 56. The inertial forces generated under rifle recoil are therefore more significant. The front interface between bases and lugs in the Suhler mount is a pure metal-to-metal contact. The rear interface, in contrast, depends on the spring loading of Suhler lug 54.
Returning now to
Those skilled in the art will also realize that the mechanical interface between Suhler slider 54 and mating notch 68 must be fitted very carefully in order for the device to work. This fitting is typically done by hand, using the Prussian blue or “thickness of smoke” process of scraping away the high spots to produce a perfect fit. As the device wears over time, this mechanical fit often tends to become loose.
My own prior invention—Front Interfacing Detachable Scope Mount—was created to solve these prior problems. That invention issued as U.S. Pat. No. 6,594,938 on Jul. 22, 2003. The present invention is an improvement over U.S. Pat. No. 6,594,938, but is quite similar in design and operation. U.S. Pat. No. 6,594,938 is hereby incorporated by reference.
The present invention comprises a detachable mount for a telescopic sight which can be operated using only one latching mechanism. The mount uses a front base attached to the ring of a rifle receiver and a rear base attached to the bridge of a rifle receiver. The upper surfaces of both the front and rear bases open into a pair of slots. A separate scope mount is attached to a scope sight by conventional means. Two sets of lugs descend from the lower surfaces of this scope mount. These sets of descending lugs are configured to fit securely within the slots in the front and rear bases when the scope mount is placed over the bases.
The forward facing surfaces of the rear set of descending lugs mate with a corresponding set of rearward facing surfaces in the slots within the rear base. These sets of mating surfaces are preferably offset from the vertical to create a wedging effect that pulls the rear of the scope mount down when it is pushed forward relative to the rifle receiver. The weight of the scope and scope mount also tends to force the rear of the scope mount downward.
The rearward facing surfaces of the front set of descending lugs open into tapered notches. The front base incorporates a transverse slider having a tapered surface which fits within the tapered notches in the front descending lugs. The interaction of this slider with the front lugs pushes the front of the scope mount forward while simultaneously pulling it down. The forward motion also serves to pull the rear of the scope mount down as described previously. Thus, the forward motion of this transverse slider tends to seat the scope mount firmly on the two bases.
When the user wishes to remove the device, the user pulls the transverse slider rearward and lifts the front of the scope mount up until the front lugs clear the front base. The user then pulls the rear lugs free from the rear base, thereby completely detaching the scope. Installation is the reverse of this procedure.
The geometry of the device employs the recoil impulse to actually promote engagement—rather than loosening it. The geometry also incorporates wear-compensating features. Finally, the geometry provides removal clearance for very large scope sights since the front of the scope is lifted for removal, rather than the back.
As shown in
Front base 26 is designed to fit on top of receiver ring 22. The reader will observe that the underside of front base 26 is shaped to mate with the cylindrical surface of receiver ring 22. The use of a cylindrical surface conforms to the cylindrical receiver ring on the particular rifle illustrated. Other rifles have other shapes—such as a dovetail shape—and the bottom of the front base should be shaped accordingly.
Two mounting holes 72 are provided in front base 26. A pair of base screws 74 are inserted into mounting holes 72 and threaded into threaded holes 70 in receiver ring 22. Base screws 74 are typically socket head cap screws. Mounting holes 72 are through-holes incorporating an upper counterbore to accommodate the socket heads of base screws 74. When base screws 74 are tightened, front base 26 is pulled tightly against receiver ring 22 and the upper extremes of base screws 74 preferably lie just below the upper surface of front base 26.
Rear base 28 is designed to fit on top of receiver bridge 24. Rear base 28 also includes a pair of counterbored mounting holes 72. A second pair of base screws 74 are used to mount it in the same fashion as that described for front base 26.
Slider 32 is placed within lateral slot 78, where it is free to translate forward (toward barrel 12) and rearward (toward receiver bridge 24). It is important for the user to be able to grasp and move slider 32. Thus, it is made long enough so that a portion sticks out each side of front base 26. In order to make slider 32 easier to grasp, a tab 34 is secured on each end. Each tab 34 is secured by placing its tab slot 36 over the exposed end of slider 32. It is then fixed in place using a screw, dowel, solder, or other conventional means. The outer surfaces of tab 34 may be textured in order to aid the user's grip. Tabs 34 serve the additional purpose of preventing slider 32 from sliding out one side or the other of front base 26. Those skilled in the art will realize that the slider and the tabs could be made as one integral unit. The use of a three-piece assembly is a matter of engineering convenience.
It is important in the device's operation that slider 32 be biased forward. This bias could be accomplished using many prior art methods, but spring loading has been found particularly effective. Thus, spring bores 76 are provided in front base 26. They run from the rear surface of front base 26 forward to intersect internally with lateral slot 78. Springs 38 are placed within spring bores 76. They are held in position by a pair of plugs 40, which can be threaded or press fit into position. Those skilled in the art will realize that with these elements in place, slider 32 will be biased toward a forward position, with its forward surfaces coming to rest against the forward surfaces of lateral slot 78.
Each slot preferably has an open side 122, and may in fact have two open sides (such as by omitting the rear surface on the embodiment shown in the view). The inclusion of an open side, while not necessary, assists in lubricating and cleaning the device, and may in some instances make it easier to manufacture.
A pair of front lugs 96 descend from the forward portion of scope mount 88. Likewise, a pair of rear lugs 98 descend from the rear portion of scope mount 88.
Front lugs 96 are designed to fit securely within front slots 80 in front base 26. The side walls produce a close sliding fit. The forward facing walls and rearward facing walls, however, have some clearance. Rear lugs 98 are designed to fit securely within rear slots 82 on rear base 28. The lateral-facing walls again produce a close sliding fit. The result of this clearance is that when scope mount 88 is placed on front base 26 and rear base 28 by inserting the respective lugs into the respective slots, it is still free to move forward and backward to some degree. It cannot, however, move laterally.
Comparing
The nearest rear lug 98 also rests within the nearest rear slot 82. There is clearance behind rear lug 98, but in the position shown there is no clearance in front of rear lug 98. In the position shown, scope mount 88 has been pushed forward until mating surface 66 on rear lug 98 has come into contact with mating surface 66 on rear base 28. Those skilled in the art will readily appreciate that the interaction of these mating surfaces produces two results: (1) rear lug 98 is pulled down until the rear of scope mount 88 rests firmly against the upper surface of rear base 28; and (2) all further forward progress of scope mount 88 relative to the two bases is stopped. The rear of scope mount 88 is thereby firmly seated with respect to rear base 28.
Scope mount 88 is pushed forward by the interaction of slider 32 with tapered notch 104 in front lug 96. The reader will recall that slider 32 is biased forward by springs.
It is important to understand how recoil is transmitted within the device. Returning now to
The recoil phenomenon produces another effect which should be explained. Recoil actually produces two impulses: First, there is a sharp impulse to the rear. Second, there is a milder forward impulse as the rifle's rearward motion is checked by the user's shoulder. In looking at
Those skilled in the art will realize that the double-impulse recoil phenomenon produces the same result. The first impulse accelerates the two bases and scope mount 88 rearward. The two bases then experience a deceleration (since they are mechanically locked to the rifle) when the user's shoulder decelerates the rifle. Scope mount 88 (with the other components attached) will travel further rearward, with the energy being expended to compress the springs biasing slider 32 into its forward position (springs 38). Springs 38 will eventually arrest scope mount 88's rearward travel with respect to the two bases. They will then propel it back forward—firmly reseating the device. Thus, by carefully selecting the stiffness of springs 38, the device actually uses the recoil to its advantage. The recoil is used to re-seat—and therefore re-zero the device—every time the rifle is fired.
If modern scope sight 16 has received a sharp blow in the field—causing the user to suspect that the zero of the device may have shifted—the user can simulate the above-described recoil effect by pulling modem scope sight 16 rearward and allowing the device to snap back into the seated position (optionally including the step of assisting the springs by manually pushing the device forward). This is actually a recommended procedure.
All the components of the invention are preferably made of steel. However, as it is commercially advantageous to produce the parts via investment casting, the steel employed need not be particularly hard. Some wear between the mating surfaces is preferably accommodated. Those skilled in the art will realize by looking at
Installation of the present device is the reverse of the procedure just described. Returning to
Installation is again the reverse. The user would start with the position shown in
It is helpful to understand some details of how the device is initially installed on a rifle. Returning to
While the bases are still loose, scope mount 88 (without modem scope sight 16) is put in place, with its lugs seated within the slots in the bases. This action ensures the alignment of the slots. While the user holds rear base 28 in place, scope mount 88 is then removed. While rear base 28 is still held, its two base screws 74 are tightened. This will likely cause rear base 28 to shift slightly. The user then reinstalls scope mount 88, wiggling front mount 26 so that all lugs firmly seat.
The reader will observe in
Those skilled in the art will appreciate that the alignment issue could be eliminated by making front base 26 and rear base 28 as a single integral piece. This option would increase the cost of the device, however. It also tends to disfigure the relatively clean appearance of the rifle when the scope sight is removed.
It is also possible to make scope mount 88 as two separate pieces—one incorporating front lugs 96 and front cradle 92, and one incorporating rear lugs 98 and rear cradle 90. This approach effectively uses the tube structure of modem scope sight 16 as a structural element. It therefore places considerable stress on modem scope sight 16, which is generally undesirable. It also makes the device more difficult to align and install. Accordingly, the embodiment illustrated in
During experimentation, the inventor has discovered that some users occasionally experience difficulty in executing the removal process illustrated in
When scope mount 88 in installed on the two bases, plunger 114 is pushed up so that its lowermost extremity is flush with the surface of the underside of scope mount 88. Those skilled in the art will realize that once slider 32 is disengaged from front lugs 96, the compressed spring within plunger 114 will extend the plunger and lift the front portion of scope mount 88.
At this point, the user has two options. If the user simultaneously pulls up on the forward portion of the scope or scope mount 88, then scope mount 88 can be removed in one continuous motion. If the user prefers, however, the user can simply release slider 32 and allow it to slide back forward. If this option is taken, springs 38 (which tend to bias slider 32 forward) will push slider forward surface 116 tightly against lug rearward surface 118. This frictional engagement will hold scope mount 88 in the elevation position shown. However, the user need only grasp the front of the scope or scope mount 88 and lift it free (without any need to manipulate the slider again). It is easy for the user to overcome the purely frictional engagement between slider forward surface 116 and lug rearward surface 118.
Thus, the second option allows the user to remove scope mount 88 as follows: (1) The user grasps tabs 34 and pulls them back to the rearward extreme of travel (which action carries slider 32 to its rearward extreme and allows the forward portion of scope mount 88 to pop up); (2) The user releases tabs 34 (which causes scope mount 88 to be frictionally secured in its popped up position); and (3) The user, at his or her convenience, then grasps the forward portion of the scope or scope mount 88 and pulls it free.
Although a plunger has been illustrated, those skilled in the art will realize that many types of mechanisms could be employed to cause the front portion of scope mount 88 to pop up when slider 32 is pulled rearward. As one example, camming surfaces could be incorporated in the rearward portions of slider 32. These camming surfaces could act against additional lugs descending from scope mount 88, so that as slider 32 is pulled rearward these camming surfaces would engage the additional lugs on scope mount 88 causing the forward portion of scope mount 88 to move upward.
Although the preceding description contains significant detail, it should not be construed as limiting the scope of the invention but rather as providing illustrations of the preferred embodiment of the invention. As an example, those skilled in the art will know that the same mechanism could be created using only a single front lug, single front slot, single rear lug, and single rear slot. The operation would be the same, with the use of dual slots and lugs being a matter of engineering choice. Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given.