U.S. patent application number 13/625790 was filed with the patent office on 2014-03-27 for firearm accessory clamp mount having rotatable locking lever and lower adjustment nut.
The applicant listed for this patent is MARK C. LARUE. Invention is credited to MARK C. LARUE.
Application Number | 20140082985 13/625790 |
Document ID | / |
Family ID | 50337468 |
Filed Date | 2014-03-27 |
United States Patent
Application |
20140082985 |
Kind Code |
A1 |
LARUE; MARK C. |
March 27, 2014 |
FIREARM ACCESSORY CLAMP MOUNT HAVING ROTATABLE LOCKING LEVER AND
LOWER ADJUSTMENT NUT
Abstract
An adjustable accessory mounting mechanism for firearms has an
accessory mount rail having clamp surfaces. A mount base member has
a clamp structure in retaining engagement with the clamp surfaces
and supports a clamp plate member for rotary clamping engagement
with the accessory mount rail. A clamp retainer screw extends
through the retainer opening and pivotally supports the clamp plate
member for rotary locking and unlocking movement. An adjustment nut
member is threaded to the clamp retainer screw and adjusts the
position of the clamp plate member. The adjustment nut is located
below the lower surface of the clamp plate and clamp support to
prevent its catching on brush, vines and other objects during field
use.
Inventors: |
LARUE; MARK C.; (Leander,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LARUE; MARK C. |
Leander |
TX |
US |
|
|
Family ID: |
50337468 |
Appl. No.: |
13/625790 |
Filed: |
September 24, 2012 |
Current U.S.
Class: |
42/90 |
Current CPC
Class: |
F41A 35/00 20130101;
F41G 11/003 20130101 |
Class at
Publication: |
42/90 |
International
Class: |
F41A 35/00 20060101
F41A035/00 |
Claims
1. An adjustable accessory mounting mechanism, comprising: an
accessory mount rail having clamp surfaces; a mount base member
having a clamp structure disposed for retaining engagement with
said clamp surfaces; a clamp support structure being defined by
said mount base member having upper and lower surfaces and defining
a retainer opening; a clamp member having a clamping portion
disposed for clamping engagement with a clamp surface of said
accessory mount rail and being moveable to a locking position
securing said mount base member to said mount rail and to an
unlocked position permitting removal of said mount base from said
mount rail; a clamp retainer member extending through said retainer
opening and pivotally supporting said clamp member for locking and
unlocking movement; and an adjustment member having adjusting
engagement with said clamp retainer member and having positioning
engagement with said clamp member, said adjustment member being
located below said lower surface of said clamp support
structure.
2. The adjustable accessory mounting mechanism of claim 1,
comprising: said clamp member having rotary movement relative to
said clamp support structure and having upper and lower clamp
surfaces and defining an elongate tapered cam surface establishing
camming relationship with a clamp surface of said accessory mount
rail; said clamp retainer member being a retainer screw having a
lower threaded end; and said adjustment member being a retainer nut
being threaded to said lower threaded end of said clamp retainer
member and having position controlling engagement with said lower
clamp surface of said clamp member.
3. The adjustable accessory mounting mechanism of claim 1,
comprising: said clamp retainer member being a retainer screw
having a shaft portion of non-circular configuration; and said
clamp member having a retainer screw aperture of non-circular
internal configuration and establishing a non-rotatable and
linearly moveable relation with said non-circular shaft portion of
said clamp retainer member.
4. The adjustable accessory mounting mechanism of claim 1,
comprising: an actuating lever extending from said clamp member and
being manually rotatable for imparting rotary locking and unlocking
movement to said clamp member.
5. The adjustable accessory mounting mechanism of claim 4,
comprising: a lock member being mounted to said mount base member
and having an actuating lever locking position engaging said
actuating lever when said clamp member is located at said locked
position thereof and preventing unlocking rotation of said
actuating lever, said lock member having an actuating lever release
position permitting manual rotation of said actuating lever and
said clamp member from said locking position.
6. The adjustable accessory mounting mechanism of claim 1,
comprising: said clamp support structure being a clamp support
platform having upper and lower platform surfaces; an annular
bushing insert being located within said retainer opening and
having a lower end projecting downwardly beyond said lower platform
surface; and said clamp member engaging said lower end of said
annular bushing insert and having spaced relation with said lower
platform surface.
7. The adjustable accessory mounting mechanism of claim 1,
comprising: a spring member being located within said retainer
opening and having force transmitting engagement with said clamp
retainer member and said clamp member and maintaining said clamp
member in engagement with said adjustment member.
8. The adjustable accessory mounting mechanism of claim 1,
comprising: an upwardly facing annular support shoulder being
defined within said retainer opening of said clamp support
structure; and an annular bushing insert being located within said
retainer opening and having positioning engagement with said
upwardly facing annular support shoulder.
9. The adjustable accessory mounting mechanism of claim 1,
comprising: an annular bushing insert being located within said
retainer opening and having a circular recess therein; said clamp
retainer member being a retainer screw having a head portion
located within said circular recess of said annular bushing insert
and defining a downwardly facing annular spring retainer groove; an
annular spring member having an upper end portion seated within
said downwardly facing annular spring retainer groove and having a
lower end portion disposed in force transmitting relation with said
clamp member.
10. The adjustable accessory mounting mechanism of claim 1,
comprising: an insert member being located within said retainer
opening and defining a circular rim and a retainer receptacle; said
clamp retainer member being a retainer screw having a screw head
portion located within said retainer receptacle; and said screw
head portion and said circular rim of said insert member being
substantially positioned in alignment and being in substantial
alignment with said upper surface of said mount base member, thus
providing said mount base with a substantially unobstructed upper
surface and minimizing the potential for inadvertently catching the
mount base on brush and other field debris during handling in the
field.
11. An adjustable accessory mounting mechanism, comprising: an
accessory mount rail having angulated clamp surfaces; a mount base
member having internal angulated clamp surface structure disposed
for retaining engagement with said clamp surfaces of said accessory
mount rail; a clamp support structure being defined by said mount
base member having upper and lower surfaces and defining a retainer
opening; a rotary clamp plate member having a tapered cam surface
clamping portion disposed for camming engagement with a tapered
clamp surface of said accessory mount rail and being rotatably
moveable to a locking position securing said mount base member to
said mount rail and to an unlocked position permitting removal of
said mount base from said mount rail; a clamp retainer screw member
extending through said retainer opening and supporting said rotary
clamp plate member for rotary locking and unlocking movement; and
an adjustment nut member being threaded to said clamp retainer
member and having positioning engagement with said clamp plate
member, said adjustment nut member and a lower end portion of said
clamp retainer screw being located below said lower surface of said
clamp support structure.
12. The adjustable accessory mounting mechanism of claim 11,
comprising: said rotary clamp plate member having rotary movement
relative to said clamp support structure and having upper and lower
clamp surfaces and defining an elongate tapered cam surface at its
periphery establishing camming relationship with a tapered clamp
surface of said accessory mount rail; said clamp retainer member
being a retainer screw having a lower threaded end and having a
shaft portion of non-circular configuration; said clamp member
having a retainer screw aperture of non-circular internal
configuration and establishing a non-rotatable and linearly
moveable relation with said non-circular shaft portion of said
clamp retainer member; and said adjustment member being a retainer
nut being threaded to said lower threaded end of said clamp
retainer member and having position controlling engagement with
said lower clamp surface of said clamp screw.
13. The adjustable accessory mounting mechanism of claim 11,
comprising: an actuating lever extending from said clamp member and
being manually rotatable for imparting rotary locking and unlocking
movement to said clamp member.
14. The adjustable accessory mounting mechanism of claim 13,
comprising: a lock member being mounted to said mount base member
and having an actuating lever locking position engaging said
actuating lever when said clamp member is located at said locked
position thereof and preventing unlocking rotation of said
actuating lever, said lock member having an actuating lever release
position permitting manual rotation of said actuating lever and
said clamp member from said locking position.
15. The adjustable accessory mounting mechanism of claim 11,
comprising: said clamp support structure being a clamp support
platform having upper and lower platform surfaces; an annular
bushing insert being located within said retainer opening and
having a lower end projecting downwardly beyond said lower platform
surface, said annular bushing insert defining a circular insert rim
and defining a retainer receptacle; said clamp plate member
engaging said lower end of said annular bushing insert and having
spaced relation with said lower platform surface; and a spring
member being located within said retainer opening and having force
transmitting engagement with said clamp retainer member and said
clamp plate member and maintaining said clamp plate member in
engagement with said adjustment nut member.
16. The adjustable accessory mounting mechanism of claim 11,
comprising: a spring member being located within said retainer
opening and having force transmitting engagement with said clamp
retainer member and said clamp member and maintaining said clamp
member in engagement with said adjustment member.
17. The adjustable accessory mounting mechanism of claim 11,
comprising: an upwardly facing annular support shoulder being
defined within said retainer opening of said clamp support
structure; and an annular bushing insert being located within said
retainer opening and being seated on said upwardly facing annular
support shoulder.
18. The adjustable accessory mounting mechanism of claim 11,
comprising: an annular bushing insert being located within said
retainer opening and having a circular recess therein; said clamp
retainer member being a retainer screw having a head portion
located within said circular recess of said annular bushing insert
and defining a downwardly facing annular spring retainer groove; an
annular spring member having an upper end portion seated within
said downwardly facing annular spring retainer groove and having a
lower end portion disposed in force transmitting relation with said
clamp member.
19. The adjustable accessory mounting mechanism of claim 11,
comprising: an insert member being located within said retainer
opening and having a circular rim defining a retainer receptacle;
said clamp retainer member being a retainer screw having a screw
head portion located within said retainer receptacle; and said
screw head portion and said circular rim of said insert member
being substantially positioned in alignment and being in
substantial alignment with said upper surface of said mount base
member, thus providing said mount base with a substantially
unobstructed upper surface and minimizing the potential for
inadvertently catching the mount base on brush and other field
debris during handling in the field.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to a lever actuated
clamp mechanism for mounting an accessory, such as a sighting
device or other implement, to an accessory mount rail of a firearm.
More particularly the present invention concerns an accessory mount
base having a rotatable locking lever actuated clamp mechanism,
with the locking lever thereof pivotally mounted beneath the mount
base structure. Even more particularly, the present invention
concerns a lever actuated clamping mechanism wherein a locking
lever and a locking cam plate are in the form of an integral
locking unit which is pivotally secured by a single retainer screw
to a support platform of the mount base structure. The present
invention provides an adjustment nut which is threaded to the
retainer screw and is located below the locking platform, thereby
ensuring that the upper portion of the locking platform is
substantially unobstructed and is unlikely to become fouled by
dirt, mud and the like, or caught on brush, vines and other
impediments as the firearm is used in a field environment.
[0003] 2. Description of the Prior Art
[0004] It is often desired to provide for attachment and support of
an accessory device on a supporting object, such as a firearm. In
the field concerning firearms, accessories, including optical
sighting devices, manual sighting devices, light emitting devices,
firearm handgrips, and the like, are often mounted to various types
of firearms to enhance the firearm sighting and handling capability
of a user.
[0005] Accessory devices, such as mechanical and optical sighting
devices have historically been mounted to the receiver or barrel of
a firearm by means of mounting screws. This is typically referred
to as a permanent mount since the accessory will typically remain
in assembly with the firearm until the firearm or the accessory
needs replacement or repair. A number of quick-release type mount
clamping systems have been developed over the years which permit an
accessory to be quickly assembled to or removed from a firearm.
These quick-release mounting systems are generally quite effective,
though several of the known quick-release mounting systems suffer
from the standpoint of accuracy. Also, many of the quick-release
sight mounts for firearms define projecting components that tend to
catch on brush, plants and other objects as a firearm is being
carried by a user. It is desirable therefore to provide an
accessory mount mechanism for firearm that provides a clean and
substantially unobstructed upper portion that eliminates or
minimizes the potential for catching and becoming tangled as the
firearm is carried in a field environment that is wooded or
contains brush, vines and other growth.
[0006] It is desirable to provide an accessory mount and clamp
mechanism that permits users to remove and replace various
accessories, even during field conditions, without any need for
tools or through the use of simple and efficient tools. It is also
desirable to provide users with the capability of easily adjusting
the clamping force that is being applied to a mount rail so that a
user can increase, decrease or repeatedly employ substantially the
same clamping force each time an accessory is removed from a
firearm and is then replaced. This is especially important in the
field of firearms where sighting devices can be removed from the
mounting rail of a firearm and re-installed in a manner that causes
the sighting device to return to its pre-set zero when it is again
clamped to its former location on an accessory mounting rail. It is
also desirable to provide an accessory mount that provides a clean
and unobstructed upper surface that minimizes any tendency of the
accessory mount system becoming fouled by catching on objects as a
firearm is carried and by accumulations of dirt, mud and other
debris that is likely to be encountered during use of a firearm in
field conditions.
SUMMARY OF THE INVENTION
[0007] It is a principal feature of the present invention to
provide a novel accessory mount and clamp mechanism for firearm
accessory mounts and for mounting accessories to other apparatus,
such as cameras, camera lenses, spotting telescopes, astronomical
telescopes and the like to the mount rails of tripods or other
supporting apparatus.
[0008] It is another feature of the present invention to provide a
novel accessory mount and clamp mechanism which facilitates
assembly or disassembly of an accessory support mount from a
mounting rail of a supporting device, even in poor light conditions
or other field conditions without risk of separating and losing any
of the components of the clamp mechanism.
[0009] Briefly, the various objects and features of the present
invention are realized by a clamp actuated accessory mounting
system that is designed particularly for mounting various
accessories, such as optical firearm sighting devices, spotting
telescopes, and the like, to accessory mounting rails such as
Picatinny rails, Weaver rails or other similar mounting rail
systems for firearms, photography equipment astronomy telescopes
and the like. The present invention incorporates a clamp base
structure having a portion that is configured for clamping
engagement with elongate, oppositely facing, tapered and undercut
surfaces of an accessory mounting rail. The clamp base structure
defines one or more laterally projecting clamp platforms or
supports, each defining a clamp actuator opening.
[0010] A hardened bushing member is seated within the clamp
actuator opening and defines a clamp actuator receptacle within
which a clamp retainer screw or bolt is received. The clamp
retainer screw has a shank or shaft that extends through an opening
of a clamp plate member that is in the form of a cam plate, having
an elongate tapered peripheral cam surface that is disposed for cam
force transmitting engagement with a tapered clamp surface of an
accessory mount rail. The shaft of the clamp retainer screw defines
a non-circular section which is received by a corresponding
non-circular opening of the cam plate member, thus permitting
linear movement of the cam plate member relative to the retainer
screw, but preventing rotation of the cam plate member relative to
the retainer screw.
[0011] An annular spring member, such as a circular wave spring, is
positioned about the shaft of the retainer screw and applies spring
force to the head of the retainer screw and to the upper surface of
the cam plate member. This spring force urges the cam plate member
downwardly and ensures that the cam plate member is maintained in
engagement with an adjustment nut member that is threaded to the
lower end of the shaft of the retainer screw. For adjusting the
position of the cam plate member to change its cam energized
clamping force against a tapered clamp surface of an accessory
mounting rail, the adjustment nut is rotated, thus moving the cam
plate member linearly with respect to the non-circular section of
the shaft of the retainer screw or permitting spring energized
movement of the cam plate member relative to the retainer screw
shaft, depending on the direction of rotation of the adjustment
nut. This arrangement permits precision adjustment of the clamping
force so that the clamp mechanism can be securely tightened,
without causing any deformation of the tapered clamp surface of the
accessory mounting rail.
[0012] To provide a light weight accessory mount mechanism, such as
for firearms, the mounting base and the support rings of the sight
mounting system is preferably composed of a light-weight material
such an aluminum alloy, hard polymer material or the like. However,
if desired, the mounting base can be machined from hardened and
more durable material such as steel, stainless steel, titanium or
the like, when strength and durability are critical considerations.
The mounting base, regardless of the material from which it is
constructed, is drilled or otherwise formed to eliminate material
and minimize the weight thereof. Since light-weight metal materials
are often quite soft and easily yielded by application of forces,
hardened metal inserts composed of stainless steel, steel or other
suitable hard materials are press-fitted or otherwise seated in
appropriate openings or receptacles of the mount structure. These
inserts are typically threaded so as to have threaded engagement
with retainer elements such as Torx or Allen screws. If desired
however, the inserts may simply be press-fitted within insert
receptacles and/or may be seated on internal seat shoulders if
forces are not present that would otherwise tend to separate an
insert from its receptacle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] So that the manner in which the above recited features,
advantages and objects of the present invention are attained and
can be understood in detail, a more particular description of the
invention, briefly summarized above, may be had by reference to the
preferred embodiment thereof which is illustrated in the appended
drawings, which drawings are incorporated as a part hereof.
[0014] It is to be noted however, that the appended drawings
illustrate only a typical embodiment of this invention and are
therefore not to be considered limiting of its scope, for the
invention may admit to other equally effective embodiments.
[0015] In the Drawings:
[0016] FIG. 1 is a side elevation view showing an a tactical
firearm having an accessory mounting rail and having an accessory
mount and clamp mechanism embodying the principles of the present
invention mounted thereto and supporting an optical sighting
device;
[0017] FIG. 2 is a top view showing the accessory mount and clamp
mechanism being of FIG. 1;
[0018] FIG. 3 is a front elevation view showing the accessory mount
and clamp mechanism of FIG. 2 in greater detail;
[0019] FIG. 4 is a section view taken along line 4-4 of FIG. 2,
showing the lever actuated pivotal clamp mechanism thereof in
detail;
[0020] FIG. 5 is an exploded isometric illustration showing a mount
base for dual lever actuated clamping mechanisms, and showing one
of the clamping mechanisms and a pivot mount opening for receiving
an identical or similar lever actuated clamping mechanism; and
[0021] FIG. 6 is an exploded isometric illustration showing the
locking cam plate pivot mechanism in detail and, together with FIG.
5, representing the preferred embodiment and best mode of the
invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0022] Referring now to the drawings and first to FIG. 1, a firearm
in the form of a tactical rifle is shown generally at 10, and
incorporates an upper receiver 12, being in pivotal assembly with a
lower receiver 14 at a pivot 16. A firearm barrel 18 is mounted to
the upper receiver 12 and a major portion of the barrel is enclosed
within an internal cavity of a handguard 20. The handguard is shown
to be mounted to the upper receiver 12 by means of a flanged
connection 22 having abutting mounting flanges that are secured in
releasable assembly by a plurality of retainer screws or by other
suitable means for retention.
[0023] The upper receiver 12 and the handguard 20 are each provided
with accessory mounting rail sections 24 and 26, each having a
multiplicity of evenly spaced ribs or ridges and grooves or spaces.
Accessory mounting rails, typically referred to as Picatinny rails
or Weaver rails, were developed many years ago and are generally
widely accepted in the tactical firearms industry for releasably
mounting a wide range of sighting devices, target illumination
devices, and various types of accessory mounts to a firearm.
Accessory mounting rails for firearm sighting devices typically
project upwardly, as viewed in FIG. 1, and are aligned with the
center-line of the bore of the barrel of a firearm to provide for
mounting optical and mechanical sighting devices, such as the
telescope 28 shown in FIG. 1, to the structure of a firearm.
Precise alignment of the mounting rails with respect to the barrel
of a firearm promotes the efficiency and accuracy of aiming and
shooting activities. The handguards and other components of typical
tactical rifle systems also incorporate accessory mounting rails
that project laterally and/or downwardly from the handguard or
other firearm component and permit the mounting of various other
devices to the structure of the firearm. For example, in FIG. 1 a
bipod 30 is shown to be mounted to a downwardly projecting
accessory mounting rail section 32 of the handguard 20. Laterally
projecting mounting rail sections 34 also extend from the handguard
structure and provide means for releasable attachment of lasers and
various other illumination devices to a firearm to promote aiming
and shooting during conditions of minimal light.
[0024] Referring now particularly to FIGS. 2 and 3 a lever actuated
accessory mounting and clamping mechanism shown generally at 40
incorporates a mount base 42 having an upper mount structure 44
that can have any suitable form for attachment of an accessory
device thereto. The mount base 42 is preferably composed of a
lightweight metal such as an aluminum alloy to minimize weight
without any sacrifice from the standpoint of strength and
durability. As shown in FIGS. 2-4 the upper mount structure 44 is
shown as a simple structural member having openings 46 to receive
various types of retainer devices to secure various types of
accessories to the mount base structure. However, it is to be borne
in mind that the upper mount base structure may have any of a
number of suitable forms that effectively tailor the mount base for
the specific accessory device that it is intended to support.
[0025] The mount base 42 is provided with spaced lateral clamp
flange members 48 and 50 that define downwardly and outwardly
angulated planar surfaces 52 and 54 that form a cavity of a
configuration matching the external geometry of an accessory mount
rail which is shown in broken lines in FIG. 4. The lateral clamp
flange member 50 defines an oppositely angulated planar undercut
surface 56 that intersects the oppositely angulated planar surface
54 and defines an internal profile that matches a portion of an
accessory mounting rail. One or more locator keys 58 project
downwardly from the lower surface portion of the mount base
structure 42 and are oriented to enter one or more spaced slots or
recesses that are defined by an accessory mounting rail of a
firearm, thus selectively locating the accessory mount mechanism on
a mounting rail and at a position that is specific to the needs and
comfort of a firearm user.
[0026] As shown in FIGS. 2, 3 and 5 an accessory mount base may be
designed to incorporate a pair of spaced lever actuated clamping
mechanisms. However, if desired, an accessory mount mechanism may
have one, two, three or more lever actuated clamping mechanisms,
depending on the use which the accessory mount is to serve. For
example, to accommodate the severe recoil of firearms shooting .50
caliber cartridges, a sight mount mechanism may have three or four
lever actuated clamping mechanisms while firearms handling standard
5.56 mm cartridges may employ a sight mount mechanism having only a
single lever actuated clamping mechanism. The accessory mounting
systems typically employ a number of lever actuated cam locking
systems that is dependent on the weight or mass of the accessory
and the force that is to be applied to the accessory during use of
a firearm. The mount base 42, as shown in FIGS. 1-3 and 5, is
provided with two spaced clamp support platforms 60 and 62. Each of
the clamp support platforms defines a circular opening 64 having an
upwardly facing annular internal support shoulder 66 as shown in
FIGS. 4 and 5.
[0027] A circular bushing insert member 68, composed of a hard and
durable material such as steel, stainless steel, etc., is
positioned within the circular opening 64 and defines a downwardly
facing annular shoulder 70 that is seated on the annular internal
support shoulder 66 of the mount base platform. The circular
bushing insert member is preferably press-fitted within the
circular opening 64; however, it may be retained within the
circular opening by a close fit or by any other suitable means. The
lower end 72 of the circular bushing insert member 68 projects
slightly beyond the downwardly facing planar surface 74, and when
engaged by the locking cam plate, provides for spacing of the upper
planar surface of a locking cam plate from the lower planar surface
of the platforms 60 and 62 as is discussed in greater detail below.
In one form of the invention, a circular support washer member 76
is positioned within a circular opening that is defined by the
circular insert member 68 and is seated on an annular upwardly
facing internal shoulder 78 of the insert member 68 and defines a
central opening 80. A wave spring member 82 is also seated on
another annular internal shoulder 84 of the insert member 68 and is
secured in position by the lower surface of the support washer
member 76.
[0028] A pivot retainer member 86 defines an enlarged circular
retainer head 88 which is received in close fitting relation within
the circular opening of the circular bushing insert member 68. The
circular retainer head 88 defines a downwardly facing circular
groove 90 within which received the upper end of an annular wave
spring member 92. The lower end of the annular wave spring member
is seated on an upwardly facing internal annular shoulder 91 that
is defined within the annular bushing insert 68. The pivot retainer
member 86 includes a downwardly extending retainer shank or shaft
94 having a lower threaded section 96 to which is threaded an
adjustment nut 98.
[0029] A cam plate member 100 defines a non-circular opening 102
through which the downwardly extending retainer shank or shaft 94
of the retainer member extends. The shank of the retainer member 86
defines a non-circular section 95 that matches and is in registry
with the non-circular opening of the cam plate member and prevents
relative rotation but permits linear movement of the cam plate
member relative to the retainer member. Thus, as the cam plate is
rotated to its locked and unlocked positions, the retainer member
86 is also rotated within the circular opening of the bushing
insert member 68. The cam plate defines a tapered cam surface 104
that establishes camming and locking engagement with an undercut
tapered locking surface 106 of an accessory mounting rail 24 or 26
of a firearm, as shown in FIGS. 1 and 4. As the cam plate is
rotated to its locked position, the tapered cam surface functions
to wedge the cam plate tightly against the tapered surface 106 of
the mount rail 24, thus drawing the opposite angulated surfaces 54
and 56 of the mount base into tight and secure locking engagement
with the mount rail. The locator key 58, being engaged within a
selected transverse slot of the mount rail, will prevent any
movement of the mount base along the length of the mount rail. When
locked to the mount rail in this fashion the mount base is secured
against any movement relative to the mount rail and will thus serve
as an efficient sight mount for a wide range of firearm sighting
devices. Moreover, by simply rotating the locking cam plate to its
unlocked position, the entire mount base and any sighting device or
other accessory that is in assembly with the mount base can be
easily removed from the mount rail. And, when the mount base is
again assembled and locked with respect to its previous position on
the mount rail, the sighting device will be positioned at its
preset zero. Thus, a firearm user may transport a rifle and a
sighting device separately to a site for use, quickly assemble the
mount base to the accessory mount rail and expect to shoot a bullet
precisely to a target, without any necessity for test shooting the
firearm to establish a zero.
[0030] A circular flange 108 that is also defined by the cam plate
member 100 about the pivot opening, projects upwardly into the
lower circular opening 110 of the circular insert member 68 and
ensures stabilization of the cam plate member during its rotation.
A locking lever member 112 is formed integrally with the cam plate
or is attached to it in any suitable fashion. A user of the firearm
will apply manual force to the locking lever to rotate the cam
plate to its locked and unlocked positions with respect to the
accessory mount rail 24. In FIG. 4 the cam plate 100 is shown in
its locked position, with its tapered cam surface 104 positioned in
force transmitting locking engagement with the undercut tapered
locking surface 106 of the accessory mounting rail 24. When the cam
plate 100 is rotated to its unlocked position by manual rotation of
the locking lever member 112 the tapered cam surface 104 will be
moved to a position that is clear of the undercut mounting rail
surface 106, thereby permitting the mount base, and any accessory
device that is secured to it, to be removed from the mounting rail
24.
[0031] As mentioned above, the cam plate member 100 defines an
upper planar surface 101 that engages the lower annular end surface
72 of the bushing insert member 68. Since the lower annular end
surface 72 projects downwardly, slightly below the level of the
planar bottom surface 74 of the platform structure 60 or 62, the
upper surface of the cam plate member will be located in slightly
spaced relation with the bottom planar surface 74, thus ensuring
that no binding condition can be developed that will retard manual
rotation movement of the cam plate member. Even though the retainer
and adjustment nut 98 is rotated to tighten the position of the cam
plate member relative to the bushing insert member, the upper
surface 101 of the cam plate member will remain in spaced relation
with the lower planar surface 74 of the platform structure 60 or
62.
[0032] With the locking lever in its locked position a lever
retention member 114, being mounted to the mount base structure 46
for linear movement, is moved forwardly or to the left as shown in
FIG. 5 to a position capturing the locking lever 112 within a lever
retention recess 116, thus preventing the lever from being
rotationally moved from its locking position.
[0033] In view of the foregoing it is evident that the present
invention is one well adapted to attain all of the objects and
features hereinabove set forth, together with other objects and
features which are inherent in the apparatus disclosed herein.
[0034] As will be readily apparent to those skilled in the art, the
present invention may easily be produced in other specific forms
without departing from its spirit or essential characteristics. The
present embodiment is, therefore, to be considered as merely
illustrative and not restrictive, the scope of the invention being
indicated by the claims rather than the foregoing description, and
all changes which come within the meaning and range of equivalence
of the claims are therefore intended to be embraced therein.
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