# US 10,369,607 B2 · Safety device of press brake and controlling method of press brake > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,369,607 B2 - Document ID: US10369607B2 - Status: Granted - Kind: B2 - Application number: 16/093,026 - Filed: 2017-03-14 - Published: 2019-05-23 - Granted: 2019-08-06 - Earliest claimed: 2016-04-14 - Assignees: Amada Holdings Co., Ltd. - Applicants: Amada Holdings Co., Ltd. - Inventors: Takayuki Aoki; Kento Matsuura; Ryota Okamoto - Web page: https://patentgrep.com/patent/US10369607B2 ## CPC - B21D 5/02: on press brakes without making use of clamping means - B21C 51/00: Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses B21B - B21F - B21D 5/004: {with program control} - B21D 55/00: Safety devices protecting the machine or the operator, specially adapted for apparatus or machines dealt with in this subclass (for presses in general B30B; safety devices in general F16P) - B30B 15/00: Details of, or accessories for, presses; Auxiliary measures in connection with pressing (safety devices F16P) - B30B 15/16: Control arrangements for fluid-driven presses (pumps per se F04; hydraulic accumulators per se F15B; valves per se F16K; control devices in general G05) - B30B 15/166: {Electrical control arrangements} - B30B 15/18: controlling the reciprocating motion of the ram - B30B 15/285: {preventing a full press stroke if there is an obstruction in the working area} - F16P 3/144: {using light grids} - H10F 39/12: Image sensors - B21D: WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (working or processing of wire B21F) - B21C: MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES, PROFILES OR LIKE SEMI-MANUFACTURED PRODUCTS OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL - B30B: PRESSES IN GENERAL (producing ultra-high pressure or ultra-high pressure and high temperature to effect modifications of a substance, e.g. for making artificial diamonds B01J3/00 ){(compressing means for refuse receptacles B65F1/1405)} - F16P: SAFETY DEVICES IN GENERAL; {SAFETY DEVICES FOR PRESSES} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION ## Abstract A projector emits laser light, and an optical receiver includes a photodetector. When an upper table is lowered, a safety controller controls lowering of the upper table to stop, when it is determined that the optical receiver is in a light obstructing state in a period in which a condition is satisfied that a first distance between a tip of a punch and an upper end of a material is equal to or greater than a second distance between the tip of the punch and the photodetector, and controls the lowering to continue without stopping the lowering of the upper table even when it is determined that the optical receiver is in the light obstructing state in a period in which a condition is satisfied that the first distance is less than the second distance. ## Claims ### Claim 1 A safety device of a press brake which includes an upper table for holding a punch, a lower table for holding a die, and an actuator which lowers and raises the upper table, the safety device comprising: a projector which is mounted on the upper table, and configured to emit laser light in such a way that the laser light passes through between the punch and the die; an optical receiver which is mounted on the upper table, comprising a photodetector which detects the laser light passing through between the punch and the die, and configured to determine whether the optical receiver is in a light receiving state of receiving the laser light, or in a light obstructing state of not receiving the laser light; and a safety controller configured, when the actuator lowers the upper table for performing a bending processing by sandwiching a material arranged on the die between the punch and the die, to control lowering of the upper table to stop, when it is determined that the optical receiver is in the light obstructing state in a period in which a condition is satisfied that a first distance between a tip on the die side of the punch and an upper end of the punch side of the material is equal to or greater than a second distance between the tip of the punch and the photodetector, and to control the lowering to continue without stopping the lowering of the upper table even when it is determined that the optical receiver is in the light obstructing state in a period in which a condition is satisfied that the first distance is less than the second distance, wherein the safety controller comprises: a comparator configured to compare the first distance with the second distance so as to output a first output value when the first distance is equal to or greater than the second distance, and to output a second output value when the first distance is less than the second distance; and an AND circuit which receives the first or second output value from the comparator, and a light obstructing output value or a non-light obstructing output value from the optical receiver, and configured to output a lowering stop signal of the upper table, only when the AND circuit receives the first output value from the comparator and the light obstructing output value from the optical receiver. ### Claim 2 (depends on 1) The safety device of the press brake according to claim 1, wherein the optical receiver comprises a plurality of first photodetectors which are arranged along a movement path of the punch, and a plurality of second photodetectors which are arranged on a front side of the plurality of first photodetectors, and is configured to determine whether the optical receiver is in the light receiving state or in the light obstructing state, based on whether each photodetector of the plurality of first and second photodetectors individually detects the laser light. ### Claim 3 (depends on 2) The safety device of the press brake according to claim 2, wherein when the material has a flange standing toward the punch side on a side of a plate-shaped plate material, the safety controller calculates the first distance with an upper end of the plate material set as the upper end of the punch side of the material, when the optical receiver determines whether the optical receiver is in the light receiving state or in the light obstructing state based on whether the plurality of first photodetectors detect the laser light, and calculates the first distance with an upper end of the flange set as the upper end of the punch side of the material, when the optical receiver determines whether the optical receiver is in the light receiving state or in the light obstructing state based on whether the plurality of second photodetectors detect the laser light. ### Claim 4 (depends on 3) The safety device of the press brake according to claim 3, wherein a value indicating a height of the flange calculated based on processing data which indicates a method of a processing of the material is supplied to the safety controller, and the safety controller calculates the first distance based on the height of the flange.