# US 2018/0023908 A1 · Cartridge-in-chamber detection system for firearms > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0023908 A1 - Document ID: US20180023908A1 - Status: Published application - Kind: A1 - Application number: 15/645,642 - Filed: 2017-07-10 - Published: 2018-01-25 - Earliest claimed: 2016-07-11 - Assignees: Rade TecnologíAS, S.L. - Applicants: Rade Tecnologías, S.L. - Inventors: Raúl DELGADO ACARRETA; Rubén ROBLES PÉREZ; Javier ATRIAN BLASCO; Diego BERNAL SOMAVILLA; Diego IBÁÑEZ MARTÍNEZ; José CUESTA ÁLVAREZ - Web page: https://patentgrep.com/patent/US20180023908A1 ## CPC - F41A 9/53: Charged-condition indicators, i.e. indicating the presence of a cartridge in the cartridge chamber - F41A: FUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE ## Abstract The present invention relates to a cartridge-in-chamber detection system for firearms which makes it possible to reliably detect the presence or non-presence of a cartridge in the chamber whilst making it possible to supply this information to the user intuitively and comprising at least two plates wherethrough it is possible to determine the variation of the electrical capacity between two possible states of the system, when there is no cartridge in the chamber and when there is a cartridge in the chamber. ## Claims ### Claim 1 Cartridge-in-chamber detection system for firearms comprising at least one first plate, a second plate and a dielectric disposed between the first plate and the second plate, and a sensor circuit connected to a microprocessor where the at least one first plate is displaceable or the dielectric varies, between a first position corresponding to the presence of a cartridge in the chamber and a second position corresponding to the non-presence of a cartridge in the chamber, or vice-versa, and where the microprocessor, through the sensor circuit, detects the capacitive variation between the first plate and the second plate, between the first position corresponding to the presence of a cartridge in the chamber and the second position corresponding to the non-presence of a cartridge in the chamber, or vice-versa, making it possible to determine in this way the presence or non-presence of a cartridge in the chamber. ### Claim 2 (depends on 1) The system of claim 1, further comprising a movement sensor which activates the system when the weapon is subject to any type of movement. ### Claim 3 (depends on 1) The system of claim 1, further comprising a light indicator which indicates to the user the presence or non-presence of a cartridge in the chamber. ### Claim 4 (depends on 1) The system of claim 1, where the second plate is disposed on the sensor circuit connected to the microprocessor. ### Claim 5 (depends on 1) The system of claim 1, where the first plate is an extractor of the weapon. ### Claim 6 (depends on 1) The system of claim 1, where in the first position corresponding to the presence of a cartridge in the chamber, the first plate is closer to the second plate than in the second position corresponding to the non-presence of a cartridge in the chamber, and therefore the capacity associated to the first position is greater than the capacity associated to the second position, or where in the first position corresponding to the presence of a cartridge in the chamber, the first plate is further from the second plate than in the second position corresponding to the non-presence of a cartridge in the chamber, and therefore the capacity associated to the first position is less than the capacity associated to the second position. ### Claim 7 (depends on 1) The system of claim 1, where the first plate is an element belonging to the weapon and the second plate is an element external to the weapon. ### Claim 8 (depends on 1) The system of claim 1, where the first plate is a plunger disposed in a slide of the weapon, plunger which is in contact with an extractor of the weapon. ### Claim 9 (depends on 8) The system of claim 8, where the first plate or plunger passes through a support piece of an elastic element which maintains the tension on the first plate or plunger. ### Claim 10 (depends on 9) The system of claim 9, where the first plate or plunger, the support piece and the elastic element are disposed in a longitudinal direction of the slide of the weapon. ### Claim 11 (depends on 1) The system of claim 1, where the first plate is an elastic element disposed in a slide of the weapon, which is in contact with a plunger which in turn is in contact with an extractor of the weapon and where the first plate or elastic element maintains the tension on the plunger as it is in contact with a support piece which is disposed inside the first plate or elastic element in the slide of the weapon, where the second plate is disposed inside the support piece. ### Claim 12 (depends on 11) The system of claim 11, where the first plate or elastic element, the plunger, the support piece and the second plate are disposed in a longitudinal direction of the slide of the weapon. ### Claim 13 (depends on 1) The system of claim 1, where in the first position corresponding to the presence of a cartridge in the chamber, the opposing area between the first plate and the second plate is greater than in the second position corresponding to the non-presence of a cartridge in the chamber, and therefore the capacity associated to the first position is greater than the capacity associated to the second position, or where in the first position corresponding to the presence of a cartridge in the chamber, the opposing area between the first plate and the second plate is less than in the second position corresponding to the non-presence of a cartridge in the chamber, and therefore the capacity associated to the first position is less than the capacity associated to the second position. ### Claim 14 (depends on 1) The system of claim 1, where the first plate has the shape of a cylinder, whilst the second plate has hollow cylinder shape, second plate which is the support piece of an elastic element which maintains the tension on the first plate with cylinder shape. ### Claim 15 (depends on 1) The system of claim 1, where in the first position corresponding to the presence of a cartridge in the chamber, the dielectric varies between the first plate and the second plate with respect to the second position corresponding to the non-presence of a cartridge in the chamber, and therefore the capacity associated to the first position is different to the capacity associated to the second position. ### Claim 16 (depends on 1) The system of claim 1, where the first plate and/or the second plate are an element belonging to the weapon. ### Claim 17 (depends on 1) The system of claim 1, where the first plate and/or the second plate are a modified element belonging to the weapon. ### Claim 18 (depends on 1) The system of claim 1, where the first plate and/or the second plate are an element external to the weapon. ### Claim 19 (depends on 1) The system of claim 1, where the first plate and/or the second plate are displaceable. ### Claim 20 (depends on 1) The system of claim 1, where the first plate and/or the second plate are fixed.