# US 11,879,873 B2 · Flexural-rigidity measuring apparatus and method for measuring flexural rigidity > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,879,873 B2 - Document ID: US11879873B2 - Status: Granted - Kind: B2 - Application number: 17/542,509 - Filed: 2021-12-06 - Published: 2023-02-02 - Granted: 2024-01-23 - Earliest claimed: 2021-07-29 - Assignees: FUJIFILM Business Innovation Corp. - Applicants: FUJIFILM Business Innovation Corp. - Inventors: Masao Omori - Web page: https://patentgrep.com/patent/US11879873B2 ## CPC - G01N 3/32: by applying repeated or pulsating forces - G01N 21/359: using near infrared light - G01N 3/068: {with optical indicating or recording means} - G01N 21/3554: for determining moisture content - G01N 21/86: Investigating moving sheets (G01N21/89 takes precedence) - G01N 27/025: {a current being generated within the material by induction} - G01N 29/11: by measuring attenuation of acoustic waves - G01N 29/4427: {with stored values, e.g. threshold values} - G01N 27/023: {where the material is placed in the field of a coil} - G01N 2021/8663: {Paper, e.g. gloss, moisture content} - G01N 2203/0008: High frequencies from 10 000 Hz - G01N 2203/0282: Two dimensional, e.g. tapes, webs, sheets, strips, disks or membranes - G01N 2203/0641: using optical, X-ray, ultraviolet, infrared or similar detectors - G01N 2291/015: Attenuation, scattering - G01N 2291/02827: Elastic parameters, strength or force - G01N 2291/048: Transmission, i.e. analysed material between transmitter and receiver - G01N 2291/102: one emitter, one receiver - G01N 2291/2632: flat - 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) ## Abstract A flexural-rigidity measuring apparatus includes an ultrasonic device including an oscillating unit that oscillates an ultrasonic wave toward a sheet and a receiving unit that receives the ultrasonic wave that has passed through the sheet, an electromagnetic induction device including an electromagnetic induction unit that generates electromagnetic induction with respect to a sheet, and a near-infrared spectroscopic device including a light-emitting unit that emits near-infrared light toward a sheet and a light-receiving unit that receives the near-infrared light that has passed through the sheet. ## Claims ### Claim 1 A flexural-rigidity measuring apparatus comprising: an ultrasonic device including an oscillating unit that oscillates an ultrasonic wave toward a sheet and a receiving unit that receives the ultrasonic wave that has passed through the sheet; an electromagnetic induction device including an electromagnetic induction unit that generates electromagnetic induction with respect to a sheet; and a near-infrared spectroscopic device including a light-emitting unit that emits near-infrared light toward a sheet and a light-receiving unit that receives the near-infrared light that has passed through the sheet. ### Claim 2 (depends on 1) The flexural-rigidity measuring apparatus according to claim 1, further comprising: a derivation unit that derives flexural rigidity of a sheet by using a measurement result of the ultrasonic device, a measurement result of the electromagnetic induction device obtained by causing the electromagnetic induction unit to move toward and away from the sheet, and a measurement result of the near-infrared spectroscopic device. ### Claim 3 (depends on 2) The flexural-rigidity measuring apparatus according to claim 2, wherein the derivation unit derives the flexural rigidity of the sheet by using a basis weight of the sheet that is obtained from the measurement result of the ultrasonic device, a thickness of the sheet that is obtained from the measurement result of the electromagnetic induction device, an amount of moisture in the sheet that is obtained from the measurement result of the near-infrared spectroscopic device, and an amount of ash in the sheet that is obtained from the measurement result of the near-infrared spectroscopic device. ### Claim 4 (depends on 3) The flexural-rigidity measuring apparatus according to claim 3, wherein the ultrasonic device, the electromagnetic induction device, and the near-infrared spectroscopic device are arranged in such a manner as to face a sheet attached to an apparatus body. ### Claim 5 (depends on 4) The flexural-rigidity measuring apparatus according to claim 4, wherein the derivation unit derives the flexural rigidity of the sheet by using Equation (Z): K=T3×(a·B/T+b·W/B+c·A/B) (Z) where K stands for the flexural rigidity of the sheet, T stands for the thickness of the sheet, B stands for the basis weight of the sheet, W stands for the amount of moisture contained in the sheet, and A stands for the amount of ash contained in the sheet, and where a, b, and c are each a predetermined constant. ### Claim 6 (depends on 3) The flexural-rigidity measuring apparatus according to claim 3, wherein the derivation unit derives the flexural rigidity of the sheet by using Equation (Z): K=T3×(a·B/T+b·W/B+c·A/B) (Z) where K stands for the flexural rigidity of the sheet, T stands for the thickness of the sheet, B stands for the basis weight of the sheet, W stands for the amount of moisture contained in the sheet, and A stands for the amount of ash contained in the sheet, and where a, b, and c are each a predetermined constant. ### Claim 7 (depends on 2) The flexural-rigidity measuring apparatus according to claim 2, wherein the ultrasonic device, the electromagnetic induction device, and the near-infrared spectroscopic device are arranged in such a manner as to face a sheet attached to an apparatus body. ### Claim 8 (depends on 7) The flexural-rigidity measuring apparatus according to claim 7, wherein the derivation unit derives the flexural rigidity of the sheet by using Equation (Z): K=T3×(a·B/T+b·W/B+c·A/B) (Z) where K stands for the flexural rigidity of the sheet, T stands for the thickness of the sheet, B stands for the basis weight of the sheet, W stands for the amount of moisture contained in the sheet, and A stands for the amount of ash contained in the sheet, and where a, b, and c are each a predetermined constant. ### Claim 9 (depends on 1) The flexural-rigidity measuring apparatus according to claim 1, wherein the ultrasonic device, the electromagnetic induction device, and the near-infrared spectroscopic device are arranged in such a manner as to face a sheet attached to an apparatus body. ### Claim 10 A flexural-rigidity measuring apparatus comprising: a first acquisition unit that acquires a basis weight of a sheet; a second acquisition unit that acquires a thickness of a sheet; and a near-infrared spectroscopic device including a light-emitting unit that emits near-infrared light toward a sheet and a light-receiving unit that receives the near-infrared light that has passed through the sheet. ### Claim 11 (depends on 10) The flexural-rigidity measuring apparatus according to claim 10, further comprising: a derivation unit that derives flexural rigidity of a sheet by using the basis weight of the sheet acquired by the first acquisition unit, the thickness of the sheet acquired by the second acquisition unit, and a measurement result of the near-infrared spectroscopic device. ### Claim 12 (depends on 11) The flexural-rigidity measuring apparatus according to claim 11, wherein the derivation unit derives the flexural rigidity of the sheet by using the basis weight of the sheet, the thickness of the sheet, an amount of moisture in the sheet that is obtained from the measurement result of the near-infrared spectroscopic device, and an amount of ash in the sheet that is obtained from the measurement result of the near-infrared spectroscopic device. ### Claim 13 (depends on 12) The flexural-rigidity measuring apparatus according to claim 12, wherein the derivation unit derives the flexural rigidity of the sheet by using Equation (Z): K=T3×(a·B/T+b·W/B+c·A/B) (Z) where K stands for the flexural rigidity of the sheet, T stands for the thickness of the sheet, B stands for the basis weight of the sheet, W stands for the amount of moisture contained in the sheet, and A stands for the amount of ash contained in the sheet, and where a, b, and c are each a predetermined constant. ### Claim 14 A method for measuring flexural rigidity comprising: oscillating an ultrasonic wave toward a sheet and receiving the ultrasonic wave that has passed through the sheet; generating electromagnetic induction with respect to a sheet; and emitting near-infrared light toward a sheet and receiving the near-infrared light that has passed through the sheet.