Firing pin indent gauge

Patent metadata

Field	Value
Publication number	US-11215418-B1
Application number	US-201916556548-A
Country	US
Kind code	B1
Filing date	Aug 30, 2019
Priority date	Aug 30, 2019
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

An in-weapon sensor enables electronic measurement of the firing pin indent force of a weapon system. The in-weapon sensor measures, either directly or indirectly, the indent force of the firing pin and communicates the information outside of the weapon to a data capture device. The data capture device provides a visual indication as to whether the firing pin indent force is sufficient or insufficient.

First claim

What is claimed is:

1. A sensor assembly for measuring an operational parameter of a firing pin, the sensor assembly comprising:
a housing sized and dimensioned to fit within a chamber of a weapon system, said housing having a forward end oriented toward the firing pin and an aft end oriented toward a barrel of the weapon system and further defining an interior cavity;
an impact nose positioned at the forward end of the housing and having an exposed front surface for receiving a firing pin impact load from the firing pin;
a sensor located within the interior cavity of the housing for sensing an effect of the firing pin impact load;
a load bypass sleeve coaxial with and substantially surrounding a circumference of the impact nose and positioned to receive a bolt impact load from a bolt of the weapon system; and
a communication interface for transmitting data corresponding to a sensed effect from the sensor assembly.

2. The sensor assembly of claim 1 wherein the operational parameter comprises one or more of the following: a firing pin force, a firing pin impulse and a firing pin energy.

3. The sensor assembly of claim 1 wherein the impact nose permanently deforms in response to receiving the firing pin impact load directly from the firing pin.

4. The sensor assembly of claim 3 wherein the impact nose is formed from a polymer.

5. The sensor assembly of claim 1 further comprising a guide tube partially housed within and extending aft of the housing, the guide tube sized and dimensioned for being received within a barrel of the weapon and further defining a hollow central interior for receiving a communication cable.

6. The sensor assembly of claim 5 wherein the guide tube applies a preload force on the sensor assembly such that sensor assembly is tensioned with respect to the chamber of the weapon system.

7. The sensor assembly of claim 1 wherein less than five percent of a bolt impact load applied to the load bypass sleeve is sensed by the sensor.

8. The sensor assembly of claim 1 wherein the sensor is a strain sensor for measuring a strain experienced in response to the firing pin impact load.

9. The sensor assembly of claim 8 wherein the strain sensor is a piezoelectric strain sensor.

10. The sensor assembly of claim 8 wherein the housing completely surrounds the strain sensor and wherein the impact nose is positioned forward of and in contact with the housing.

11. The sensor assembly of claim 8 wherein the sensor assembly is for use in a weapon system which is chambered for 5.56 mm center fire rifle ammunition.

12. The sensor assembly of claim 1 wherein the load path of the sensor is from the impact nose to the sensor and does not comprise the housing.

13. The sensor assembly of claim 12 wherein the force sensor is a piezoelectric force sensor.

14. The sensor assembly of claim 12 wherein a surface of the force sensor is in contact with the impact nose.

15. The sensor assembly of claim 12 wherein the load bypass sleeve is integral to the housing.

16. A system for measuring an operational parameter of a firing pin of a weapon system, the system comprising:
a sensor assembly, the sensor assembly further comprising
a housing sized and dimensioned to fit within a chamber of a weapon system and defining an interior cavity,
an impact nose positioned at a forward end of the housing and having an exposed front surface for receiving a firing pin impact load from the firing pin;
a sensor located within the interior cavity of the housing for sensing an effect of the firing pin impact load;
a load bypass sleeve coaxial with and substantially surrounding a circumference of the impact nose and positioned to receive a bolt impact load from a bolt of the weapon system;

a communication interface for transmitting data corresponding to a sensed effect from the sensor assembly;
a guide tube extending aft of the housing and sized and dimensioned for being received within and extending beyond a barrel of the weapon and further defining a hollow central interior for receiving a communication cable of the communication interface;
a pretensioner assembly defining a hollow central interior sized and dimensioned to receive a portion of the guide tube, wherein the pretensioner assembly applies a preload on the sensor assembly via the guide tube such that sensor assembly is tensioned with respect to the chamber of the weapon system; and
a data capture device for receiving the sensed load and providing an indication of the sensed load.

17. The sensor assembly of claim 16 wherein the operational parameter comprises one or more of the following: a firing pin force, a firing pin impulse and a firing pin energy.

18. The system of claim 16 wherein the sensor is a strain sensor for measuring a strain experienced in response to the firing pin impact load and wherein the housing completely surrounds the strain sensor and the impact nose is positioned forward of and in contact with the housing.

19. The system of claim 16 wherein the sensor is a force sensor for measuring a force experienced in response to the firing pin impact load wherein a surface of the force sensor is in contact with the impact nose.

Assignees

• Us Gov Sec Army
• Us Army

Inventors

• Grego Thomas C
• Gandy Christopher
• Donovan Brian
• Kirchen Adrial
• Kinsberg Jeffrey
• Orsini Andrew

Classifications

• F41A31/00 Primary

  Testing arrangements (testing mounts F41A23/16) · CPC title

• G01L1/16

  using properties of piezoelectric devices · CPC title

• G01L5/0052

  measuring forces due to impact (G01L5/0061, G01L5/14 take precedence; impact testing of structures G01M7/08; impact testing of material G01N3/00) · CPC title