# US 7,406,876 B2 · Sensor arrangement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,406,876 B2 - Document ID: US7406876B2 - Status: Granted - Kind: B2 - Application number: 10/542,057 - Filed: 2004-01-19 - Published: 2006-09-21 - Granted: 2008-08-05 - Earliest claimed: 2003-01-17 - Assignees: Vasensor AB - Inventors: Anatol Krozer; Christer Johansson; Sofia Johnsson; Brodde Wetter; Henrik Danielsson; Gustav Perers - Web page: https://patentgrep.com/patent/US7406876B2 ## CPC - G01L 5/045: {for measuring the tension across the width of a band-shaped flexible member (measuring flatness G01B)} - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) ## Abstract The present invention relates to a system for detecting characteristics of an elastic structure (13, 22, 23, 32, 33, 93, 1202, 1302, 1402), said structure being provided with at least one sensor (111, 112, 14, 211, 212, 311, 312, 911, 1211, 1311, 1411) and said system comprising at least one detector (16, 416, 516, 916, 1316, 1416). The sensor comprises a deformable member, which upon deformation generates a signal convertible to a signal representing said characteristic, said sensor further comprises a passive transmitter and said detector a receiver for receiving said signal representing said characteristic. ## Claims ### Claim 1 A system for detecting at least one physical characteristic of an elastic structure subjected to a force under a motion, said structure being provided with at least one sensor comprising a first and a second electrodes and a piezoelectric material, which upon deformation generates a charge displacement in the material giving rise to a voltage between said first and second electrodes being directly proportional to the force causing the deformation, said voltage being convertible to a signal representing said characteristic, and said system comprising at least one detector comprising a receiver for receiving said signal representing said characteristic, wherein said sensor further comprises a first sensor conductor being connected to said first electrode and a second sensor conductor being connected to said second electrode, said first and said second sensor conductors being arranged as antennas, and wherein said detector comprises a receiver antenna arranged adjacent to said elastic structure for capacitively sensing said voltage between said first and said second sensor conductors, thereby enabling determination of said characteristic. ### Claim 2 (depends on 1) The system of claim 1, wherein said structure is a flat structure. ### Claim 3 (depends on 1) The system according to claim 1, wherein said structure is a belt, a conveyer, a wire, a sheet material, a paper sheet, a fabric, a cloth, a printing paper, paper money, or bank notes, and said structure cooperates/interacts with at least one substantially cylindrical rotating body. ### Claim 4 (depends on 3) The system according to claim 3, wherein said at least one substantially cylindrical rotating body is a roll. ### Claim 5 (depends on 4) The system according to claim 4, wherein said structure cooperates/interacts with two rolls. ### Claim 6 (depends on 4) The system according to claim 4, wherein said structure cooperates/interacts with three rolls. ### Claim 7 (depends on 4) The system according to claim 4, wherein the roll(s) is/are arranged in a paper-manufacturing machine, said structure is a belt or a conveyer, and sensors are arranged inside the material of the belt, either in the longitudinal and/or transverse direction of the belt. ### Claim 8 (depends on 4) The system according to claim 4, wherein the roll(s) is/are arranged in a printer application, said structure is a printing paper, and at least one sensor is arranged on the surface of the printing paper or substantially within the printing paper. ### Claim 9 (depends on 8) The system according to claim 8, wherein the sensor comprises a foil integrated substantially inside the paper. ### Claim 10 (depends on 4) The system according to claim 4, wherein the rolls are arranged in a banking paper application, said structure is bank notes or paper money, and the sensor is arranged as a strip on the surface of the bank note/paper money or substantially within the bank note/paper money. ### Claim 11 (depends on 1) The system of claim 1, wherein said structure is a substantially cylindrical rotating structure. ### Claim 12 (depends on 11) The system according to claim 11, wherein the sensor deforms during a time period, whereby a part of the structure that contains the sensor is in contact with a surface, whereby during said time period, an electric signal or voltage/current pulse is created, and a linear velocity of rotation is obtained if the length of the sensor is known by dividing this length by the duration of the voltage/current pulse. ### Claim 13 (depends on 12) The system of claim 12, wherein additional information is provided by a frequency at which pulses occur due to the rotation of the structure, both related to each other and to a linear velocity of the structure motion, and a difference in linear velocity of the structure calculated from the pulse duration and from the frequency of structure rotation varying in time indicates skid. ### Claim 14 (depends on 1) The system according to claim 1, wherein the structure comprises a tyre. ### Claim 15 (depends on 1) The system according to claim 1, wherein the structure comprises a roll, a roller, a cylinder, a delivery bowl, rubber-covered cylinder, drum, or a hole cylinder. ### Claim 16 (depends on 1) The system according to claim 1, wherein the structure is a roll or a cylinder feeding a sheet material. ### Claim 17 (depends on 1) The system of claim 1, wherein said sensor, including the transmitter, is arranged on or inside said structure. ### Claim 18 (depends on 1) The system of claim 1, wherein said structure comprises an oblong structure passing through a pressing arrangement. ### Claim 19 (depends on 1) The system according to claim 1, wherein said structure is a conveyer shaped structure in a nip formed by rolls, and at least one sensor is arranged on the surface of the conveyer shaped structure or substantially within the conveyer shaped structure for detecting the pressure and pressure distribution in the nip between the rolls. ### Claim 20 (depends on 19) The system according to claim 19, wherein the nip is present in a nip roll, a roller press, an Yankee machine, a shoe press, or a smoothing coating machine of a paper-manufacturing machine. ### Claim 21 (depends on 20) The system according to claim 20, wherein the characteristic(s) detected is/are the nip force, nip pressure/pressure distribution and/or nip width of the rolls in a nip roll press. ### Claim 22 (depends on 1) The system of claim 1, wherein the sensor is arranged in one of or several of a longitudinal, radial or transversal direction of the structure. ### Claim 23 (depends on 1) The system of claim 1, wherein the sensor is arranged to provide one or several of absolute linear velocity or skid characteristic of the structure. ### Claim 24 (depends on 1) The system of claim 1, wherein one or several sensors constitute(s) a bar code in the structure. ### Claim 25 (depends on 1) The system as claimed in claim 1, wherein the sensor is formed as a cable, a filament, a strip, a foil, a thread, a film, a particle or the like. ### Claim 26 (depends on 1) The system according to claim 1 ,wherein the receiver antenna comprises two conductive plates. ### Claim 27 (depends on 1) The system according to claim 1, wherein the receiver comprises a differential amplifier, an analogue-digital converter, and a signal-processing unit. ### Claim 28 (depends on 1) The system according to claim 1, wherein several sensors are placed in an overlapping arrangement in the structure allowing continuous signal acquisition and measurement of pressure distribution in the width direction of the structure. ### Claim 29 (depends on 1) The system according to claim 1, wherein the sensor comprises two conductors extending from the ends of the sensor, and the sensor being folded providing two shanks, one of which can be subjected to a force, such that the sensor operates in bending mode. ### Claim 30 (depends on 1) The system according to claim 1, wherein the first and second sensor conductors are spaced apart in such a way that minimum or null electric field lines are between the first and second sensor conductors, and the main part of the electric field lines are between each pair of sensor conductor and receiver antenna. ### Claim 31 (depends on 1) The system according to claim 1, wherein an extension of the receiver antennas is larger than an extension of the first and second sensor conductors. ### Claim 32 (depends on 1) The system according to claim 1, wherein one receiver antenna is used for each sensor conductor. ### Claim 33 (depends on 1) The system according to claim 1, wherein the piezoelectric material is polyvinylidenfluoride (PVDF). ### Claim 34 (depends on 1) The system according to claim 1, wherein a differential signal between a sensor subjected to said force and a sensor not being subjected to said force is used. ### Claim 35 (depends on 34) The system according to claim 34, wherein the differential signal technique is used to measure temperature variations. ### Claim 36 (depends on 1) Use of a system according to claim 1 in an apparatus comprising at least one substantially cylindrical rotating body feeding a sheet material for detecting at least one physical characteristic of said sheet material. ### Claim 37 (depends on 36) The use according to claim 36, wherein the movement, presence of material, rotation speed, and/or sliding characteristics is/are detected. ### Claim 38 (depends on 36) The use according to claim 36, wherein said sensor is used in a paper-manufacturing machine for detecting a characteristic of a belt or a conveyer cooperating/interacting with at least one substantially cylindrical rotating body feeding said belt, said sensor(s) being integrated into the belt/conveyer, either in the longitudinal and/or transverse direction of the belt. ### Claim 39 (depends on 36) The use according to claim 36, wherein said sheet material is a conveyer shaped structure in a nip formed by rolls, said sensor being arranged on the surface of the conveyer shaped structure or substantially within the conveyer shaped structure for detecting the pressure and pressure distribution in the nip between the rolls. ### Claim 40 (depends on 39) The use according to claim 39, wherein the nip is present in a nip roll, a roller press, an Yankee machine, a shoe press, or a smoothing coating machine of a paper-manufacturing machine. ### Claim 41 (depends on 40) The use according to claim 40, wherein the characteristic(s) detected is/are the nip force, nip pressure and/or nip width of the rolls in a nip roll press. ### Claim 42 (depends on 36) The use according to claim 36, wherein said sensor is used in a printer application for detecting a characteristic of a printing paper cooperating/interacting with at least one substantially cylindrical rotating body feeding said printing paper, said sensor(s) being arranged on the surface of the printing paper or substantially within the printer paper. ### Claim 43 (depends on 36) The use according to claim 36, wherein the sensor is used in a banking paper application for detecting a characteristic of bank notes or paper money cooperating/interacting with at least one substantially cylindrical rotating body feeding said bank notes/paper money, said sensor(s) being arranged on the surface of the bank notes/paper money or substantially within the bank notes/paper money. ### Claim 44 (depends on 1) A method of detecting at least one physical characteristic of an elastic structure subjected to a force under a motion using the system according to claim 1, the method comprising: providing said structure with at least one sensor comprising a first and a second electrodes and a piezoelectric material, which upon deformation generates a charge displacement in the material giving rise to a voltage between said first and second electrodes being directly proportional to the force causing the deformation, said voltage being convertible to a signal representing said characteristic, wherein said sensor further comprises a first sensor conductor being connected to said first electrode and a second sensor conductor being connected to said second electrode, said first and second sensor conductors being arranged as antennas; providing at least one detector comprising a receiver antenna, in such a way that said receiver antenna is arranged adjacent to said elastic structure; and capacitively sensing a voltage between said first and second sensor conductors by means of said receiver antenna, thereby enabling determination of said characteristic. ### Claim 45 A sensor arrangement for incorporation into an elastic structure and for providing at least one physical characteristic of said structure when subjected to a force under a motion, said sensor comprising a first and a second electrodes and a piezoelectric material, which upon deformation generates a charge displacement in the material giving rise to a voltage between said first and second electrodes being directly proportional to the force causing the deformation, said voltage being convertible to a signal representing said characteristic, wherein said sensor further comprises a first sensor conductor being connected to said first electrode and a second sensor conductor being connected to said second electrode, said first and second sensor conductors being arranged as antennas in such a way that capacitive sensing of said voltage between said first and said second sensor conductors is enabled when said sensor is incorporated in the elastic structure. ### Claim 46 (depends on 45) The sensor arrangement according to claim 45, wherein the sensor is formed as a cable, a filament, a strip, a foil, a thread, a film, a particle or the like. ### Claim 47 (depends on 45) The sensor arrangement according to claim 45, wherein said first and second sensor conductors are spaced apart in such a way that minimum or null electric field lines are between the transmitting antennas. ### Claim 48 (depends on 45) The sensor arrangement according claim 45, wherein the piezoelectric material is polyvinylidenfluoride (PVDF). ### Claim 49 (depends on 45) A belt having a sensor arrangement according to claim 45 embedded therein, thereby enabling detection of a force acting on said belt.