# US 11,305,447 B2 · Pipe cutting machine with a controlled floating cutting mandrel, and cutting method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,305,447 B2 - Document ID: US11305447B2 - Status: Granted - Kind: B2 - Application number: 16/765,500 - Filed: 2018-11-16 - Published: 2020-10-08 - Granted: 2022-04-19 - Earliest claimed: 2017-11-20 - Assignees: Rattunde AG - Applicants: Rattunde AG - Inventors: Ulrich Rattunde - Web page: https://patentgrep.com/patent/US11305447B2 ## CPC - B26D 3/164: {characterised by means for supporting the tube from the inside} - B23D 21/14: cutting inside the tube - B23D 33/02: Arrangements for holding, guiding, and/or feeding work during the operation - B23D 35/001: {cutting members} - B26D 2007/013: {the work being tubes, rods or logs} - B26D: CUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING (for growing crops or plants A01D, A01G; for fodder or straw A01F; for bulk butter A01J; for dough A21C; slaughtering A22B; for tobacco, cigars or cigarettes A24; marking-out, perforating or making buttonholes A41H25/00; manufacturing footwear A43D; brushmaking A46D; surgery A61B; disintegrating, mincing or shredding in general B02C; cutting wire, making pins or nails B21F, B21G; of the kind used formetal B23; cutting by abrasive fluid jets B24C5/02; hand-held cutting tools B26B; perforating, cutting-out, stamping-out or punching, or severing by means other than cutting B26F; for wood B27; for stone B28D; working of plastics or substances in a plastic state B29; making boxes, cartons, envelopes or bags, of paper or similarly worked materials, e.g. metal foil, B31B; article or web delivery apparatus incorporating cutting or line-perforating devices B65H35/00; for leather or upholstery B68, C14B; for glass C03B; making matches C06F; for peat C10F; for sugar C13B45/00; for textile materials D06H; civil engineering, building, mining, see Section E; for light guides G02B6/25; cutting processed photographic material G03D15/04) - B23D: PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR (making toothed gears or the like B23F; cutting metal by applying heat locally B23K; arrangements for copying or controlling B23Q) ## Abstract A pipe cutting machine with a pipe (3), from which a pipe section (3a) is to be cut to size, a stationary cutting die (1), a movable cutting die (2) which can be moved relative to the stationary cutting die (1), and a cutting mandrel (13) which is introduced into the pipe (3) and which comprises a stationary mandrel (14) and a mandrel (16) that can be moved relative to the stationary mandrel (14). The cutting mandrel (13) is arranged in a cutting position during a cutting process, and the cutting mandrel (13) is arranged in the pipe (3) in a floating manner. A magnetic coupling (6) is provided with a coupling stator (7) arranged outside of the pipe (3) and a coupling rotor (21) arranged on the stationary mandrel (14). ## Claims ### Claim 1 Pipe cutting machine with a pipe (3), from which a pipe section (3a) is to be cut to size, a stationary cutting die (1), a movable cutting die (2) which can be moved relative to the stationary cutting die (1), and a cutting mandrel (13) which is introduced into the pipe (3) and which comprises a stationary mandrel (14) and a mandrel (16) that can be moved relative to the stationary mandrel (14), wherein the cutting mandrel (13) is arranged in a cutting position in a floating manner, characterised in that the cutting mandrel (13) is arranged in the pipe (3) in a floating manner, and a magnetic coupling (6) is provided with a coupling stator (7) arranged outside of the pipe (3) and a coupling rotor (21) arranged on the stationary mandrel (14), and a movement of a magnetic field of the magnetic coupling (6) in a longitudinal direction (L) can be controlled using control values, and a position sensor (8) has a sensor stator (12), which is connected to a frame in a fixed position, and a sensor rotor (19), which is connected to the stationary mandrel (14) in a fixed position, said position sensor being used to measure deviations of the cutting mandrel (13) from the cutting position, and a control unit converts deviation measurement values into the control values, by means of which the cutting mandrel (13) can be returned to the cutting position. ### Claim 2 (depends on 1) Pipe cutting machine according to claim 1, characterised by an eccentric drive for the movable cutting die (2). ### Claim 3 (depends on 1) Pipe cutting machine according to claim 1, characterised in that the sensor rotor (19) has at least two magnetic poles spaced apart from one another in the longitudinal direction (L) and the sensor stator (12) has at least two sensor rings (9, 10, 11) each having at least two Hall effect sensors (91, 92, 93, 94, 95, 96, 101, 102, 103, 104, 105, 106, 111, 112, 113 114 115, 116). ### Claim 4 (depends on 3) Pipe cutting machine according to claim 3, characterised in that the Hall effect sensors (91, 92, 93, 94, 95, 96, 101, 102, 103, 104, 105, 106, 111, 112, 113, 114, 115, 116) are connected to the control unit, measurement values of the Hall effect sensors (91, 92, 93, 94, 95, 96, 101, 102, 103, 104, 105, 106, 111, 112, 113 114 115, 116) of each of the sensor rings (9, 10, 11) are in each case assigned a sensor ring measurement value, and from a change to sensor ring measurement value differences a deviation of the cutting mandrel (13) from the cutting position is calculated and the deviation measurement values are generated. ### Claim 5 Method for cutting pipe sections (3a) of a pipe (3) to size, wherein a floating cutting mandrel (13) is introduced into the pipe (3), the pipe (3) is introduced into a die cutter (1, 2) having a die gap (17) until a cutting surface between the pipe section (3a) and the pipe (3) is arranged in an extension of the die gap (17), the floating cutting mandrel is oriented in the longitudinal direction (L) and moved into a cutting position in which a cutting mandrel gap (18) is arranged in the extension of the die gap (17), a position sensor (8) measures deviations of the cutting mandrel (13) from a cutting position and feeds the deviations to a control unit, the control unit converts the deviation measurements into control values and feeds the control values to a magnetic coupling (6), which moves the cutting mandrel (13) back into the cutting position. ### Claim 6 (depends on 5) Method according to claim 5, characterised in that measurement values of Hall effect sensors (91, 92, 93, 94, 95, 96, 101, 102, 103, 104, 105, 106, 111, 112, 113, 114, 115, 116) arranged along a sensor ring (9, 10, 11) are measured and processed to produce a sensor ring measurement value, and the sensor ring measurement values of at least two sensor rings (9, 10, 11) are determined and are compared with sensor ring measurement values of a zero position, and deviation measurement values are calculated from the comparison. ### Claim 7 (depends on 6) Method according to claim 6, characterised in that the measurement values of the Hall effect sensors (91, 92, 93, 94, 95, 96, 101, 102, 103, 104, 105, 106, 111, 112, 113 114 115, 116) of the sensor ring (9, 10, 11) are averaged. ### Claim 8 (depends on 7) Method according to claim 7, characterised in that differences between the averaged measurement values are calculated and compared with the differences of averaged measurement values of the cutting position.