Note: Descriptions are shown in the official language in which they were submitted.
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FIREARM ROUND COUNTER AND ASSEMBLY
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No
60/957,512, filed August 23, 2007, which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to firearms. More particularly, the
invention
relates to a round counter and round counter assembly for a firearm, such as a
rifle for
example.
BACKGROUND OF THE INVENT!ON
[0003] Firearms, such as pistols, rifles, shotguns and similar weapons, are
commonly used in many different safety, combat, law enforcement and
recreational
settings. Depending on the setting, it can be important to track the number of
rounds
which are fired from the weapon over a particular period of time. This
information may
be important for training purposes, to monitor the frequency of situations
where the
weapon is fired, or for assessing the maintenance schedule and lifespan of the
firearm
or components thereof.
[0004] There is also a need in some situations, particularly law enforcement
or
military situations, to be able to prove whether or not a weapon has been
fired, and how
many times, and ideally when. Ideally, it would be possible to determine the
total
number of rounds fired and when the round(s) was/were fired.
[0005] There have been several attempts to incorporate mechanisms into
firearms
for monitoring the number of rounds fired. These mechanisms have typically
been bulky
mechanical devices which are often complex and subject to frequent mechanical
failure.
They can also add unnecessary weight to the firearm. Furthermore, many of the
known
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mechanisms, such as those described in United States patent no. 5,406,730
(Sayre)
and United States patent no. 5,799,432 (Wright), only count the number of
rounds of
ammunition remaining in the magazine of the firearm at a point in time, rather
than
counting rounds fired.
[0006] United States patent no. 3,792,638 (Cox) discloses a fluidic system of
counting the number of rounds fired from an artillery gun barrel. The fluidic
components
sense the zone charge used and the system computes the effective number of
rounds
fired. Each time the gun is fired, gas from the barrel passes through a check
valve, a
fluidic diode, into a capacitor. The collected gas in the capacitor is then
fed to a fluidic
oscillator via a regulator. The fluidic oscillator is the type that has an
output frequency
independent of the temperature. The collected pressure is a function of the
zone charge
used, and the duration of the oscillator output is related directly to the
zone charge.
Each round produces a weighted number of oscillations from the oscillator
which is then
counted and displayed.
[0007] United States patent no. 4,001,961 (Johnson) discloses a round counter
and
circuitry attached to a weapon for indicating the extent of its use. The
indicator is an
elapsed time meter comprising a capillary tube, a cathode, an anode and a
mercury
column interrupted by an electrolytic gap. When a round is fired, a current
passes
through a circuit and mercury atoms are ionized; the movement of the ions
causes the
electrolytic gap to migrate from the cathode to the anode. This migration is a
proportional to the product of current and time and results in a
quantification of round
firing.
[0008] United States patent no. 5,033,217 (Brennan) discloses a round counter
for a
small arms weapon. Wear indicator surfaces intermediate to a bolt slide and a
frame
receiver of a pistol are provided in the weapon. As the surfaces wear away,
the visual
patterns of the surfaces change, indicating an approximate number of rounds
fired. The
problem with this design is that it can only qualitatively, rather than
quantitatively,
determine the amount of rounds fired. Additionally, this design does not
analyze the
frequency of firing.
[0009] United States patent no. 5,303,495 (Harthcock) discloses a firearm
controlled
by a microprocessor. A means connected to the microprocessor provides time,
date and
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muzzle-pointing azimuth information for each of the rounds of ammunition
fired. The
processor detects how many rounds remain in the magazine; it does not,
however, keep
a running count of the total number of rounds fired by the weapon.
[0010] United States patent no. 5,566,486 (Brinkley) discloses a device which
monitors the recoil of the firearm to provide a count of the total number of
rounds
discharged through the firearm. A display on the device indicates the number
of rounds
fired. The device also comprises a microcontroller.
[0011] There remains a need for a practical and efficient round counter for a
firearm,
which requires minimal intervention from the user. It is also desirable to
provide a round
counter which monitors the number of rounds fired, whether for scheduled
maintenance
of the firearm, training purposes, evidentiary purposes, or whatever.
SUMMARY OF THE INVENTION
[0012] In view of the foregoing, embodiments of the present invention provide
an
improved or alternative round counter for firearms.
[0013] In a first aspect, the invention provides a round counter assembly for
a
firearm, embodied for example in a pin used for securing the upper receiver of
the
firearm (which typically supports the barrel assembly of the firearm) to the
lower
receiver (which is typically assembled with the stock, trigger assembly,
pistol grip, etc.).
A housing located on one end of the pin contains a sensor, for example an
accelerometer or audio signal transducer sensor, which detects the firing of a
round
from the firearm by a user. A data processor in the housing is connected to
the sensor
for receiving and storing data related to the firearm.
[0014] The data related to the firearm can comprise a count of the number of
rounds
fired from the firearm. The data can or could also include frequency of firing
the firearm,
time of firing, angle of firing trajectory, identity of the firearm, identity
of the user, and/or
any other desired data.
[0015] In a further aspect, the invention provides a round counter for a
firearm
comprising a sensor for detecting the firing of the firearm, a microchip
connected to the
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sensor, and a data processor on the microchip for receiving and storing data
related to
the firearm.
[0016] Preferred embodiments of the invention are intended to be as compact as
possible, due to the limited space available. Preferably this means without
fitting into the
pistol grip, which would eliminate valuable space otherwise typically used for
batteries
or cleaning kits. Preferred embodiments also add as little weight as possible
to the
system.
[0017] Other aspects and features of the invention will become apparent upon
review of the following description of specific embodiments of the invention,
in
conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWiNGS
[0018] Embodiments of the invention will now be described, by way of example
only,
with reference to the attached drawings, wherein:
[0019] Fig. 1 is a perspective view of a round counter assembly according to
the
invention;
[0020] Fig. 2 is an exploded view of the round counter assembly of Fig. 1; and
[0021] Fig. 3 shows a typical rifle with the round counter assembly of the
invention.
DETAILED DESCRIPTION
[0022] Generally, the invention provides a round counter assembly for a
firearm. In
the preferred embodiment, the round counter assembly comprises a pin for
connecting
upper and lower receivers of the firearm, a housing mounted on one end of the
pin, a
sensor in the housing for detecting the firing of ammunition from the firearm
by a user,
and a data processor in the housing and connected to the sensor for receiving
and
storing data related to the firearm.
[0023] Although the round counter could be a stand-alone piece secured to the
firearm by some other means, it is advantageous to mount it on a pin, the pin
being
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configured to replace the standard take-down pin which connects the upper and
lower
receivers of the firearm.
[0024] In the exemplary embodiment described herein, the round counter is used
in
a rifle. However, the round counter can be used in any weapon which fires
projectiles,
such as a pistol, rifle, shotgun or the like.
[0025] The round counter assembly comprises a means for sensing the firing of
ammunition from the firearm. This means can include a round counter comprising
a
sensor for detecting the firing of the firearm, a microchip connected to the
sensor, and a
data processor on the microchip for receiving and storing data related to the
firearm.
[0026] Fig. 1 shows a preferred embodiment of the round counter assembly of
the
invention. In this embodiment, the assembly 10 includes a pin 12 and a round
counter
housing 14 at one end of the pin. As indicated previously, the pin preferably
is
configured to replace the standard take-down pin of the firearm, rather than
constituting
an additional part (and additional weight). The housing 14 can be rectangular
in shape,
as illustrated, but any practical shape may be used. The housing can provide
thermal,
reflex and/or shock protection, and includes a cover (not specifically
illustrated) to
protect the contents of the housing from damage, debris and/or moisture.
[0027] Fig. 2 is an exploded view of the round counter assembly. A chip 20
mounted
within the housing 14 has data processor circuitry 22 (illustrated
schematically only).
The chip 20 and circuitry 22 log the number of rounds fired with the use of a
miniature
audio signal transducer sensor (not shown) in the round counter assembly. The
sensor
can have a built-in filter to eliminate spurious data. Instead of an audio
signal transducer
as a sensor, the round counter could use an accelerometer.
[0028] The circuitry 22 in the round counter assembly 10 can be powered by a
battery (not shown), such as a watch battery or equivalent.
[0029] The sensor can have a count rate of 300 to 1500 rpm. The bullet exit
impulse
is about 2 ms or better, the buffering impulse is about 30 ms or better, and
the counter
recoil impulse is about 45 ms or better.
[0030] In one embodiment, the sensor has a maximum counting rate of about
12,000
rpm. The sensor can have a timestamp which can be programmable. The timestamp
can be in ASCII or binary format. The timestamp can have a resolution maximum
in the
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millisecond range and a minimum resolution in the year range. The maximum
number of
counts between resets with a time stamp is about 2,000,000; the maximum number
of
counts between resets without a time stamp is about 20,000,000,000. The sensor
can
have built-in non-volatile memory storage.
[0031] In addition to counting the number of rounds fired, the circuitry 22
can also log
other statistics such as the time(s) the weapon was fired, the frequency of
firing (shots
per unit time, or time between shots), and/or the angle of trajectory of the
firing. The
circuitry 22 can also distinguish a live firing from a dry firing (e.g.,
pulling the trigger
without ammunition in the firearm, banging the firearm against the ground,
etc.). In the
case of an accelerometer, for example, the circuitry detects impulses from the
accelerometer, and the time between impulses enables the calculation of
whether a live
round is being fired or whether the impulses are due to some spurious event
such as
banging the rifle butt on the ground. In any live firing, there is a typical
recoil and
counter-recoil with a distinctive acceleration signature which is not present
in other
events, so that these other events can be ignored.
[0032] In addition, the circuitry 22 can be programmed with information, such
as, for
example, the maintenance schedule for the firearm, identity of the firearm,
the user,
location of usage (e.g., theatre of battle, etc.), country or mission.
[0033] ~ At any time, the round counter assembly 10 andlor the chip 20
comprising the
data processor circuitry 22 therein may be removed from the firearm for
analysis. A
scanner or round counter reader (not shown) can be used to read the circuitry
22 on the
chip 20 and report the number of rounds fired, or any of the data described
herein. The
scanner can be portable, which can greatly facilitate the determination of
rounds fired in
the field or in a remote location. The scanner can be integrated with
different interfaces,
e.g. USB, wireless (Bluetooth, etc.), and the data can be password protected.
Additional
software can be used to tabulate and analyze the data obtained by the scanner
from the
round counter assembly chip 20.
[0034] Fig. 3 shows the location 32 of the round counter assembly of the
invention
as installed in a typical rifle 30. The round counter assembly can be
incorporated into
existing firearms. Firearms which incorporate a standard take-down pin may be
retrofitted by replacing the pin with the present round counter assembly 10,
without
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affecting or modifying the function of the weapon. The pin 12 of the round
counter
assembly 10 can be inserted into the rifle 30 in the same way and at the same
location
as previously-known take-down pins. In one embodiment, and as illustrated in
Fig. 3,
the round counter assembly 10 is placed at the front of the lower receiver.
[0035] The above-described embodiments of the invention are intended to be
examples only. Alterations, modifications and variations may be effected to
the
particular embodiments by those of skill in the art without departing from the
scope of
the invention.
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