Determination of round count by hall switch encoding

Patent metadata

Field	Value
Publication number	US-12535283-B2
Application number	US-202318336392-A
Country	US
Kind code	B2
Filing date	Jun 16, 2023
Priority date	Oct 22, 2018
Publication date	Jan 27, 2026
Grant date	Jan 27, 2026

Abstract

This disclosure describes systems, methods, and apparatus for detecting and displaying a number of rounds in a firearm magazine comprising a maximum number of N rounds. The magazine may comprise a follower, magnets on the follower, and <N magnetic-field-sensing sensors arranged along a path of the magnets when the follower moves along a length of the magazine, the sensors generating round count data based on a position of the one or more magnets relative to the <N magnetic-field-sensing sensors, and a first substantially flat antenna arranged on an inside of the magazine and configured to wirelessly transmit a round count indication to a second substantially flat antenna on the firearm, the round count indication based on the round count data, the second substantially flat antenna affixed to an inside of a magazine well of the firearm and mostly overlapping with the first substantially flat antenna.

First claim

What is claimed is:

1 . A method of round count communications for a firearm, the method comprising:
sensing movement of a firearm magazine with an accelerometer; initializing a microcontroller unit (MCU) in response to the sensed movement; activating at least a first magnetic-field-sensing sensor of a plurality of magnetic-field-sensing sensors arranged substantially along an inside of the magazine; receiving a signal from the first magnetic-field-sensing sensor in response to a magnet being proximate the first magnetic-field-sensing sensor; determining a location of the magnet within the magazine based on a location of the first magnetic-field-sensing sensor; deactivating at least one second magnetic-field-sensing sensor of the plurality of magnetic-field-sensing sensors; and using the MCU to compute a round count from the location of the first magnetic-field-sensing sensor.

2 . The method of claim 1 , further comprising coupling the MCU to a first flat antenna and transmitting the round count to a second flat antenna.

3 . The method of claim 2 , further comprising transmitting the round count to a user interface.

4 . The method of claim 1 , further comprising activating at least one third magnetic-field-sensing sensor of the plurality of magnetic-field-sensing sensors proximate the first magnetic-field-sensing sensor.

5 . The method of claim 4 , wherein the at least one third magnetic-field-sensing sensor is adjacent the first magnetic-field-sensing sensor.

6 . The method of claim 4 , further comprising:
receiving a signal from the at least one third magnetic-field-sensing sensor as the magnet moves in the magazine; and using the MCU to compute the round count from a location of the at least one third magnetic-field-sensing sensor.

7 . The method of claim 6 , further comprising deactivating the first magnetic-field-sensing sensor in response to receiving the signal from the at least one third magnetic-field-sensing sensor.

8 . The method of claim 6 , further comprising deactivating all of the plurality of magnetic-field-sensing sensors except the at least one third magnetic-field-sensing sensor.

9 . The method of claim 1 , wherein the magnetic-field-sensing sensors are switches.

10 . The method of claim 1 , wherein the magnetic-field-sensing sensors are hall effect switches.

11 . The method of claim 1 , further comprising:
deactivating the plurality of magnetic-field-sensing sensors; and activating at least one magnetic-field-sensing sensor of the plurality of magnetic-field-sensing sensors in response to sensing movement of the firearm magazine with the accelerometer.

12 . The method of claim 1 , further comprising deactivating one or more of the plurality of magnetic-field-sensing sensors in response to no signal being received from the one or more of the plurality of magnetic-field-sensors for a predetermined period.

13 . The method of claim 12 , further comprising activating the one or more of the plurality of magnetic-field-sensing sensors that most recently detected the magnet;
determining whether the magnet moved when the one or more of the plurality of magnetic-field sensing sensors was deactivated; deactivating the one or more of the plurality of magnetic-field-sensing sensors in response to determining that the magnet did not move; and activating at least one of the plurality of magnetic-field-sensing sensors in response to determining that the magnet moved.

14 . A round counting system for a firearm, the system comprising:
a detachable magazine comprising a follower, the follower comprising one or more magnets, and the magazine comprising a plurality of magnetic-field-sensing sensors arranged substantially along a path of the one or more magnets, the magnetic-field-sensing sensors each generating a signal based on a position of the one or more magnets relative to each of the magnetic-field-sensing sensors; and a magazine processor coupled to each of the magnetic-field-sensing sensors and configured to convert the signal from each of the magnetic-field-sensing sensors into a single round count indication for the magazine, wherein the magazine processor is configured to: activate at least a first magnetic-field-sensing sensor of the plurality of magnetic-field-sensing sensors; receive a signal from the first magnetic-field-sensing sensor in response to the one or more magnets being proximate the first magnetic-field-sensing sensor; determine a location of the one or more magnets within the magazine based on a location of the first magnetic-field-sensing sensor; and deactivate at least one second magnetic-field-sensing sensor of the plurality of magnetic-field-sensing sensors.

15 . The round counting system of claim 14 , wherein the magazine processor is further configured to activate at least one third magnetic-field-sensing sensor of the plurality of magnetic-field-sensing sensors proximate the first magnetic-field-sensing sensor.

16 . The round counting system of claim 15 , wherein the at least one third magnetic-field-sensing sensor is adjacent the first magnetic-field-sensing sensor.

17 . The round counting system of claim 15 , wherein the magazine processor is further configured to:
receive a signal from the at least one third magnetic-field-sensing sensor as the one or more magnets moves in the magazine; and compute a round count from a location of the at least one third magnetic-field-sensing sensor.

Assignees

• Magpul Ind Corp

Inventors

• Czarnecki Erin
• Holt Jeffrey
• Leighton Michael
• Mckelvey Donald
• Dunbar Steven
• Roberts Timothy Eric
• Kielsmeier Nicholas
• Chow Eric

Classifications

• F41A9/62 Primary

  having means for indicating the number of cartridges left in the magazine, e.g. last-round indicators (last-round safeties F41A17/40) · CPC title

• F41A19/01 Primary

  Counting means indicating the number of shots fired · CPC title