Note: Descriptions are shown in the official language in which they were submitted.
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Adapter for a Gun
The invention relates to an adapter for attaching a device, in particular a
Harris bipod, to a
projective rail or father rail, in particular a Weaver or Picatinny rail, of a
gun, a crossbow or
suchlike, whereby the top of the device has surfaces and means, in particular
a tie rod for
tightening the device on the father rail.
A similar adapter for attaching a bipod for a gun is shown in US 2005/0188588
Al and in US
20051088597 Al.
Below, we assume the normal position of the gun and the attached device in the
form of a bipod,
i.e. with a horizontal bore axis and a horizontal transverse axis. In this
connection, "top" also
means "facing the gun" and "bottom" also means "facing away from the gun". But
other devices
with similar mechanics such as this bipod are also possible and these devices
do not need to be
attached to the bottom of the gun.
The Harris bipod has long been known for the benchrest guns, military
sharpshooter guns and
any guns requiring a secure, calm support for releasing a precision shot. A
number of marksmen
have such a Harris bipod and almost every gun can be equipped with one.
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This Harris bipod has two long, padded support surfaces that are slightly
tilted towards the
horizontal mid-line. There are two mainly vertical, powerful fingers, which
lie adjacent to each
other in the transverse direction and each of the top ends of which have a
pin, arranged between
the support surfaces. The fingers can be moved upwards using a knurled head
screw, where they
can be moved apart against the force of a spring, or downwards, where the
fingers then run into a
slotted piece, which pushes them apart and thus the pins as well and makes it
impossible to
separate them.
A counter surface is located on the front shaft of the gun on both sides and
symmetrical to its
longitudinal axis. A block, which has a transverse bore hole, sits between the
counter surfaces.
The block can, for example, sit on a pusher, which is inserted into a central,
horizontal,
embedded dove-tail longitudinal rail or mother rail or can e.g. be screwed
directly onto the shaft.
When attaching the bipod, its fingers are pushed upwards and apart against the
force of the
spring until the pins are located on both sides of the transverse bore hole of
the block. The fingers
are then released so that the pins engage with the transverse bore hole. Then
the knurled head
screw is pulled, whereby the fingers are moved downwards with the help of a
lever, in turn pulling
the block and counter surfaces downwards until contact surfaces and counter
surfaces reach full
bearing.
The special advantage of this known bipod is that it can be removed when not
in use and only
needs to be attached when needed
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so that e.g. a marksman can have several guns, which are suitable for the
attachment of a bipod,
but only one single bipod is needed. However, one disadvantage is that a
protruding pin must be
securely attached to the pin on the gun. For reasons of stability, it is not
advisable to dismantle
the block, since the thread(s) for its mounting could otherwise be rejected;
in any case, a tool and
a single skill are required for this. Thus, as a general rule, the protruding
block remains on the
gun, where it is obstructive, until the bipod is attached.
The gunsmith should perform the retooling of a gun for the attachment of a
bipod. The clean
attachment of the clean thread requires technical expertise that a hobbyist
does not have.
The bipod is normally attached as far forward on the gun as possible. But
sometimes the territory,
in which the a sharp shooter wants to position himself, can make another
attachment point
desirable or it may be desired that a laser range finder be inserted into the
mother rail in front of
the bipod. But this type of arrangement is then rendered impossible for
constructional reasons.
The attachment of add-on devices (sights, laser range finders, night target
device, spotlight,
additional hand grip, etc.) has become increasingly important of late, so that
special, projecting,
relatively wide rails or father rails (so-called Picatinny or Weaver rails)
are attached to the front
side of all types of weapons and even on the bottom side of the shaft or hand
guard. New guns
can be provided with such rails, but existing guns can also be equipped with
father rails. Since
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these rails are relatively wide and somewhat long, they do not impede support
on the body and
do not get stuck in shrubbery, etc.
Devices that are provided with a mother rail or a mother profile can be slid
on easily. If the jaws of
the mother profile can be moved, the devices are also fit and tightened from
above or from below.
The case of the latter, the devices can engage in a transverse groove of the
father rail, whereby
slipping along the father rail is rendered impossible.
At any time, a block can be placed on the bottom side of this type of rail
that is attached below the
barrel, as is provided for the attachment of the aforementioned bipod. The
aforementioned
disadvantages, which have such a prominent block, must be taken into
consideration. Moreover,
no other device can be pushed onto a rail with this type of block on the front
side.
The object of the invention is to counteract the aforementioned disadvantages
in a gun or
suchlike with a father rail attached, in particular, on the bottom.
This object is achieved in accordance with the invention in a known adapter
such that it
- comprises a coupling female fitting on the father rail, which is capable of
reaching behind the
flanks of the father rail and which has counter surfaces on the bottom side
for the support of the
support surfaces,
- has a device for immobilizing the coupling female on the father rail, and
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- comprises a block projecting downwards from the coupling female, which is
arranged between
the counter surfaces in order to hook in a tie rod.
In accordance with the invention, the block is not attached to the father
rail, but rather to a
coupling female. The coupling female can not only be removed after the
dismantling of the device
for its immobilization of the father rail, but can also be moved as desired if
another attachment
point is desired or unavoidable.
One could potentially think that the attached coupling female would be rather
cumbersome with
the block, when the device or bipod is removed (when the bipod is mentioned
below, in addition
to the Harris bipod, any device with the same attachment arrangement is
meant). However, the
bipod remains securely attached to the block; at least, the fingers are not
moved or pressed apart
when the bipod knurled head screw needs to be detached, so that the bipod
always remains on
the block. The situation that the separate block protrudes from the coupling
female, while the
coupling female is attached to the gun, does not occur with proper use, since
the coupling female
is always also removed when the bipod is removed from the gun. The bothersome,
protruding
block, which represents the biggest disadvantage of the Harris bipod, does not
appear according
to the invention.
If the bipod is used in a weapon, which has no Weaver or Picatinny rail or
suchlike (father rail),
the free ends of the fingers of the bipod are pushed together when the knurled
head screw is
removed and the coupling female with block is removed. But this only takes
place after the entire
arrangement, made up of the bipod and the coupling female, is removed from the
father rail. A
shooter, who has obtained a gun
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with a father rail or who has attached a father rail to a gun, can not only
continue to use the Harris
bipod, but can also continue to use it on his other guns that do not have a
father rail, but rather
only a protruding block.
In the case of a particularly narrow front shaft, it is possible to insert an
intermediate piece
between the coupling female and the contact surfaces of the bipod. However, it
is preferred that
the bottom side of the coupling female has the size and shape of a section,
preferably the front
end, of the front shaft or hand guard of a gun or suchiike. The counter
surfaces are thus designed
directly on the bottom side of the mother piece. Since a Weaver or Picatinny
rail is relatively wide,
the coupling female must not be overly broadened. If the coupling female is
made of metal, e.g.
an aluminum alloy, or is made of hard plastic, it is also possible to design
the counter surfaces to
be narrower than the contact surfaces of the bipod. The thus-achieved, high
surface pressure is
harmless for a coupling female made of metal or a hard plastic. The length of
the coupling
female, as seen from the longitudinal direction of the gun, should preferably
at least correspond
with that of the contact surfaces.
It would be possible introduce transverse grooves or slits into the counter
surfaces for weight
reduction. However, according to the invention, each of the counter surfaces
is preferably
designed as one piece. Since the contact surfaces are provided with an
elastomer overlay, this
would be pressed onto the edges of the slit and damaged over time during
shooting. However, it
was discovered that the continuous longitudinal edges of the coupling female,
if it is overlapped
laterally from the contact surfaces,
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does not damage the elastomer overlay of the bipod due to its low stress.
If the coupling female is designed as one piece, then it is, as in a
conventional telescopic site, is
pushed onto the rail (usually) from the front. If there is already a spotlight
or a laser range finder,
then it must be removed first. The bipod with adapter is then pushed on and
then the spotlight or
laser range finder is attached. This is somewhat cumbersome. In order to avoid
these
circumstances, it is suggested according to another preferred version of the
invention that the
coupling female has two parts, which can be pivoted around a longitudinal,
central swivel axis so
that they firmly encompass the side flanks of the father rail when it is
pivoted up and thus form the
device for immobilizing the adapter on the father rail. Thus, at first, the
one-piece coupling female
is changed to a two-piece, which represents a certain effort. However, it has
been determined
that no only the adapter and thus the bipod can be installed and removed at
any position on the
father rail diagonal to it, but rather that the immobilization device is
replaced by the two parts.
The immobilization device is served by the bipod. When the knurled head screw
of the bipod is
tightened after being installed, each of the contact surfaces pushes the
corresponding counter
surface upwards, where it reaches around the flank of the father rail and
securely clamps on it
against the other part. When removed, both parts pivot apart when the knurled
screw of the bipod
is detached again. The adapter thereby remains on the bipod as long as both
free ends of the
fingers are pushed together when detached.
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When installing and removing the bipod, the same and only the same handgrips
are required, as
without the adapter, but no permanently installed block is required, as would
be the case without
an adapter. Rather, the bipod with its adapter can be installed on each
suitable father rail and at
any position where there is space. After the adapter is removed, the weapon is
not changed, i.e.
no protruding, obstructive block exists, as was previously the case without an
adapter.
In accordance with the invention, another embodiment exists in that a
protrusion or a ridge is
designed to engage with a transverse groove on the father rail at least on the
top side of one of
the pivotable parts. This embodiment can preferably only be used if the rail
has transverse
grooves. For example, when the weapon is retracted, i.e. when forces are
attached to the bore
axis on the adapter, the surfaces of the adapter, which encompass the father
rail laterally and
clamp the adapter there, are not strained. Rather, the load is transferred
directly to the father rail
by the ridge.
It would be possible to design the block as one piece with the coupling
female, even if it is one
piece. In accordance with another embodiment of the invention, it is
particularly advantageous
that the block is made of metal, preferably steel, and protrudes from the
bottom side of the
adapter. The coupling female or its parts can be made of light metal alloy or
plastic. As long as
the anchoring of the block is reliably released in this light metal or
plastic, a particularly stable but
(due to the option of die casting or injection molding) particularly cost-
effective solution is
obtained. It is thereby unimportant how high the surface pressures become when
hooking the
pins of the fingers of the bipod, because if
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a suitable metal is selected for the block, these surface pressures still lie
far below the load limit
of the block material.
For the two-piece coupling female, another embodiment is preferably suggested,
which consists
in that the block has a longitudinal bushing on its top side, which is
penetrated by the swivel axis.
The swivel axis, which can be produced cost-effectively as a simple swivel
plate made of any
metal, is largely supported on both parts of the coupling female. The swivel
axis penetrates the
bushing so that a secure support is found. Moreover, it should be ensured that
the block can take
up a position for each of the two coupling females, which corresponds with
half of the angle that
both coupling females can take up with respect with each other.
In order to simplify the removal of the bipod with adapter, it is preferred
that both parts of the
adapter are pushed by a spring into a position, in which they release the
father rail. The
installation of the adapter is also simplified, as the spring ensures that
both parts of the coupling
female are spread apart if they are not pushed together by the contact
surfaces. Thus, it is also
possible to place it overhead, i.e. it can be placed on the upwards pointing
gun from above.
It is thereby particularly advantageous that the spring is designed as a wire
spring, which is
wound around the swivel axis and presses from above with each of its legs on
one of the parts of
the adapter. The spring is thus a simple, particularly cost-effective wire
bending part.
In an advantageous embodiment, the adapter is made up of only five parts, of
which only the
block
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is somewhat complicated to produce, e.g. as a precision cast part. The other
parts are simple die
casting or bending parts for the parts of the coupling female, a simple
automated swivel plate for
the swivel axis and a bending part for the spring. A spring ring may be
required to hold the swivel
axis. The most expensive part by far, namely, the block, was also required up
to now. This
minimal additional effort not only enables the attachment of the unchanged
bipod to a father rail,
but also the attachment at any position without leaving a mark after removal.
It is also preferred that the block on the longitudinal bushing has an upwards
pointing nose, which
is designed to engage with a transverse groove on the father rail. When the
adapter and bipod
are placed on the father rail, the nose engages with a transverse groove on
the father rail and
sinks slightly when the knurled head screw is pulled, but not so far that it
is removed from the
transverse groove. Thus, in the same manner, the nose ensures the fit of both
parts of the mother
rail in the direction of fire, as the aforementioned protrusion or ridge also
did, which can thus be
dispensed with in the case of the nose.
The object of the invention is explained in greater detail using an exemplary
embodiment, which
is shown in the drawing, but which is not intended to restrict the invention
in any way. The
following is shown in the drawing:
Fig. 1 shows the side view of a hand guard of a rapid fire gun, with the
adapter installed, whereby
the bipod is left off for a better overview,
Fig. 2 shows the longitudinal cut (cut A-A in Fig. 3) through the illustration
in Fig. 1,
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Fig. 3 shows the front view of the hand guard in Fig. 1,
Fig. 4 shows the cross-section (cut B-B in Fig. 2) through the hand guard and
adapter, whereby
the bipod is indicated, and
Fig. 5 shows a 3D top view of the removed adapter.
Figures 1 through 4 show a one-piece hand guard 5 made of aluminum, which is
pushed from the
front over the barrel and the gas intake of a rapid fire weapon. A front-site
support does not sit on
the barrel, as is customary; instead, the site is located on the hand guard 5,
in particular on the
Picatinny rail 7. Four Picatinny rails 7 are arranged on the hand guard 5,
namely an upper, a
lower and two lateral rails. An arrow C in Fig. 1 and 2 indicates the forward
direction, i.e. the
direction of fire.
An adapter, which is always labeled with the number 1, is clamped with the
Harris bipod on the
lower Picatinny rail 7. This Harris bipod is generally known and is thus not
illustrated here for
clarity; only the upper section of part 4, which has the contact surfaces 11,
is shown in Fig. 4 in
cross-section.
The adapter 1 is made up of two pivot parts 2, 3, which can pivot around an
axis 13. The pivot
part 2 has three laterally protruding hinged appendages 15, into which three
lateral hinged
appendages 17 of the pivot part 3 engage. A recess 19 is left between the
middle hinged
appendages 15 of the pivot part 2, into which a bushing 21 engages, which is
designed on the top
of the block 23 as one piece.
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A continuous bore hole 25, in which the axis 13 sits with slight play, runs
through the hinged
appendages 15, 17 and through the bushing 25.
The part of the bore hole 25, which runs through the bushing 21, can be
somewhat smaller than
the bore hole 25 through the appendages 15, 17 so that the bushing 21 and thus
the one-piece,
interconnected block 23 with press fit sit on the axis 13. An axis head may
thus be unnecessary
on one end and a spring washer may be unnecessary on the other end of the axis
13.
The block 23 protrudes downwards and outwards between the two pivot parts 2,
3, is approx.
square in cross-section and has a cross-hole 27. It is thus identical to the
known attachment
block for Harris bipods, but is different in that it has bushing 21 in place
of the known assembly
device on the top side. This bushing 21, together with the other parts of the
adapter 1, guarantees
that the cross-hole 27 of the block 23 is always positioned diagonal to the
direction of fire.
A nose 31, which is located on the top side of the block 23 and thus bushing
21, engages with a
transverse groove 33 on the Picatinny rai17 (generally referred to as "father
rail" in the above
description). The nose 31 prevents the adapter 1 from detaching to the front
or back in relation to
the father rail 7.
Figure 5 shows a version, in which a recess is left between two hinged
appendages 17 of the
pivot part 3 and a helical spring 29 is pushed onto the axis 13. Both ends of
the spring 29
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are designed as legs protruding radially in opposite directions. The legs lie
in corresponding
indentations of the pivot parts 2, 3, so that the pivot parts 2, 3 are pivoted
apart in a direction,
pointing away from the rail 7.
When installing the Harris bipod, the knurled head screw is first loosened and
the pins are hung
into the cross-hole 27 on the top end of the fingers of the bipod (not shown
in the drawing) from
both sides. The pivot parts 2, 3 are then pivoted apart as long as this does
not still occur through
the helical spring 29 displayed and explained in the embodiment in Fig. 5. The
adapter 1 with
bipod is then attached from below on the rail 7, whereby the upper, lateral
flanks of the adapter 1
or the pivot parts 2, 3 can be pushed upwards from below over the side flanks
of the rail 7. The
knurled head screw of the Harris bipod is then pulled, whereby the block 23 is
pulled down
slightly between the upper parts 4 of the Harris rail so that each of the
contact surfaces 11 from
below sit on a counter surface 35 of the pivot part 2, 3. The pivot parts 2, 3
are pivoted upwards
with the edge such that each of the lateral edges of the pivot part 2, 3
overlap and attached
securely to this lateral edge. Elastomer overlays on the contact surfaces 11
can further improve
the permanent connection, since they counterbalance small alignment errors.
When the Harris bipod is removed, its knurled head screw is loosened. The two
pivot parts 2, 3
then pivot apart due to the effect of gravitational forces or are pushed apart
by the helical spring
29 (Fig. 5) so that the rail, father rail or Picatinny rail 7 is released and
the bipod can be easily
removed
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towards the bottom. The pins thereby remain in contact with the cross-hole 27
so that the bipod
and adapter 1 always remain together.
The removal and installation of the bipod with adapter 1 is thus much easier,
as is the case
without adapter 1.
When the marksman wants to remove adapter 1, e.g. when the bipod needs to be
used on
another gun with a conventional mount and without a father rail, he just needs
to push the bottom
ends of the fingers together when the bipod is detached. The adapter 1 can
then be lifted up and
out. This is the same activity as when the bipod is detached from a gun with a
conventional
mount.
The adapter 1 thus does not limit the uses of the bipod in any way, but rather
expands the options
for use. A gun with a father rail requiring the adapter 1 also remains
undamaged, even if the
bipod is attached, while in the case of a conventional mount, a block needs to
be attached, which
affects the appearance of the gun and also protrudes from the gun. Its options
for use without a
bipod are thus considerably affected.
The exemplary embodiment shows the hand guard 5 without a father rail and the
two pivot parts
2, 3 made of aluminum alloy, while the axis 13 is made of steel. The block 23
with bushing 21 can
be made of aluminum or steel. But all other types of materials are also
possible, as long as they
meet demands, especially like hard plastic for the pivot parts 2, 3.
