# US 9,354,214 B2 · Gas sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,354,214 B2 - Document ID: US9354214B2 - Status: Granted - Kind: B2 - Application number: 14/233,683 - Filed: 2012-07-19 - Published: 2014-06-12 - Granted: 2016-05-31 - Earliest claimed: 2011-07-20 - Assignees: Corentium AS - Applicants: Bjorn Magne Sundal; Erlend Bolle; Koki Yoshioka - Inventors: Bjorn Magne Sundal; Erlend Bolle; Koki Yoshioka - Web page: https://patentgrep.com/patent/US9354214B2 ## CPC - G01T 1/178: for measuring specific activity in the presence of other radioactive substances, e.g. natural, in the air or in liquids such as rain water - G01N 33/0009: {General constructional details of gas analysers, e.g. portable test equipment (devices for withdrawing samples in the gaseous state G01N1/22)} - G01T 7/00: Details of radiation-measuring instruments - Y10T 29/49826: Assembling or joining - G01T: MEASUREMENT OF NUCLEAR OR X-RADIATION (radiation analysis of materials, mass spectrometry G01N23/00; tubes for determining the presence, intensity, density or energy of radiation or particles H01J47/00) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A gas sensor instrument comprises a housing formed of two parts (102, 10) and a diffusion chamber inside the housing. The diffusion chamber is formed from two parts (106, 108) and at least one of the diffusion chamber parts is formed integrally with one of the housing parts. This allows a reduction in size of the instrument without compromising the size of the diffusion chamber. Additionally, a tubular projection is formed integrally with one of the housing parts to form part of a Faraday cage for shielding an amplifier circuit of the instrument. ## Claims ### Claim 1 A gas sensor instrument, comprising: first and second housing parts which mate together to form an instrument housing; and first and second diffusion chamber parts which mate together to form a diffusion chamber; a detector located within the diffusion chamber; and a first printed circuit board housed within the instrument housing; where the printed circuit board is arranged to process a signal from said detector; wherein at least one of the first and second diffusion chamber parts is integrally formed with at least one of the first and second housing parts. ### Claim 2 (depends on 1) A gas sensor instrument as claimed in claim 1, wherein the first diffusion chamber part is integrally formed with the first housing part and the second diffusion chamber part is integrally formed with the second housing part. ### Claim 3 (depends on 1) A gas sensor instrument as claimed in claim 1, wherein one of the first and second diffusion chamber parts is an inner diffusion chamber part and the other is an outer diffusion chamber part, and wherein the first and second diffusion chamber parts overlap with each other such that a perimeter wall of the inner part is disposed inside a perimeter wall of the outer part. ### Claim 4 (depends on 3) A gas sensor instrument as claimed in claim 3, wherein the overlap is at least 5 mm. ### Claim 5 (depends on 3) A gas sensor instrument as claimed in claim 3, wherein the overlap is in the range 5 to 15 mm. ### Claim 6 (depends on 3) A gas sensor instrument as claimed in claim 3, wherein the first and second diffusion chamber parts are each formed as a tube, open at one end and closed at the other, wherein a second printed circuit board is disposed within the diffusion chamber and wherein the second printed circuit board is clamped between the open end of one diffusion chamber part and the closed end of the other diffusion chamber part. ### Claim 7 (depends on 3) A gas sensor instrument as claimed in claim 3, wherein the first and second diffusion chamber parts are each formed as a tube, open at one end and closed at the other, and wherein the inner diffusion chamber part comprises one or more spacer projections on a rim thereof to ensure a minimum air gap adjacent the rim. ### Claim 8 (depends on 3) A gas sensor instrument as claimed in claim 3, wherein one of the first and second diffusion chamber parts is provided with one or more spacers in the overlap region to ensure a minimum separation between the two chamber parts. ### Claim 9 (depends on 3) A gas sensor instrument as claimed in claim 3, wherein one of the first and second diffusion chamber parts is provided with a channel for accommodating an electrical conductor passing through the overlap region from the inside to the outside of the chamber. ### Claim 10 (depends on 9) A gas sensor instrument as claimed in claim 9, wherein the channel is formed in the outer diffusion chamber part and wherein the diffusion chamber wall has increased thickness in the region of the channel. ### Claim 11 (depends on 1) A gas sensor instrument as claimed in claim 1, wherein the inner surfaces of the first and second housing parts are electrically conductive. ### Claim 12 (depends on 1) A gas sensor as claimed in claim 1, wherein the sensor is a radon gas sensor. ### Claim 13 A method of making a gas sensor instrument comprising first and second housing parts first and second diffusion chamber parts, a detector and a first printed circuit board for processing a signal from said detector, wherein the first diffusion chamber part is integrally formed with the first housing part and the second diffusion chamber part is integrally formed with the second housing part and wherein the method comprises simultaneously mating the first housing part with the second housing part and the first diffusion chamber part with the second diffusion chamber part such that the detector is located between the first and second diffusion chamber parts and the first printed circuit board is housed between the first and second housing parts. ### Claim 14 (depends on 13) A method as claimed in claim 13, wherein one of the first and second diffusion chamber parts is an inner diffusion chamber part and the other is an outer diffusion chamber part, and wherein the mating step causes the first and second diffusion chamber parts to overlap with each other such that a perimeter wall of the inner part is disposed inside a perimeter wall of the outer part. ### Claim 15 (depends on 14) A method as claimed in claim 14, wherein the overlap is at least 5 mm. ### Claim 16 (depends on 14) A method as claimed in claim 14, wherein the overlap is in the range 5 to 15 mm. ### Claim 17 (depends on 14) A method as claimed in claim 14, wherein the first and second diffusion chamber parts are each formed as a tube, open at one end and closed at the other, wherein the method comprises inserting a second printed circuit board into the outer diffusion chamber part and wherein the mating step clamps the second printed circuit board between the open end of one diffusion chamber part and the closed end of the other diffusion chamber part. ### Claim 18 (depends on 14) A method as claimed in claim 14, wherein the first and second diffusion chamber parts are each formed as a tube, open at one end and closed at the other, and wherein the inner diffusion chamber part comprises one or more spacer projections on a rim thereof to ensure a minimum air gap adjacent the rim. ### Claim 19 (depends on 14) A method as claimed in claim 14, wherein one of the first and second diffusion chamber parts is provided with one or more spacers in the overlap region to ensure a minimum separation between the two chamber parts. ### Claim 20 (depends on 14) A method as claimed in claim 14, wherein one of the first and second diffusion chamber parts is provided with a channel for accommodating an electrical conductor passing through the overlap region from the inside to the outside of the chamber. ### Claim 21 (depends on 20) A method as claimed in claim 20, wherein the channel is formed in the outer diffusion chamber part and wherein the diffusion chamber wall has increased thickness in the region of the channel. ### Claim 22 (depends on 13) A method as claimed in claim 13, wherein the inner surfaces of the first and second housing parts are electrically conductive and wherein the mating step electrically connects the first and second housing parts. ### Claim 23 (depends on 13) A method as claimed in claim 13, wherein the sensor is a radon gas sensor.