US 12,152,918 B2
Assist gas flow rate calculation device and calculation method
Kaori Igarashi, Kanagawa (JP); and Shigeaki Kitaoka, Kanagawa (JP)
Assigned to AMADA CO., LTD., Kanagawa (JP)
Appl. No. 17/290,928
Filed by AMADA CO., LTD., Kanagawa (JP)
PCT Filed Oct. 24, 2019, PCT No. PCT/JP2019/041611
§ 371(c)(1), (2) Date May 3, 2021,
PCT Pub. No. WO2020/095690, PCT Pub. Date May 14, 2020.
Claims priority of application No. 2018-211174 (JP), filed on Nov. 9, 2018.
Prior Publication US 2021/0404847 A1, Dec. 30, 2021
Int. Cl. G01F 1/42 (2006.01); B23K 26/14 (2014.01)
CPC G01F 1/42 (2013.01) [B23K 26/1437 (2015.10)] 15 Claims
OG exemplary drawing
 
1. A device for calculating a flow rate of an assist gas ejected from a tip end of a nozzle attached to a processing head in laser processing in which a laser beam guided from a laser oscillator to the processing head is applied on a workpiece to perform desired processing, the assist gas flow rate calculation device comprising a control unit and a storage unit,
the storage unit storing
a first computer program calculating the flow rate using a linear function having a pressure of the assist gas in the processing head as a variable, and
a second computer program calculating a slope of the linear function using a function having a gap from the tip end of the nozzle to a surface of the workpiece as a variable,
the control unit being configured to
acquire data indicating a value of the gap,
calculate the slope by substituting the value of the gap into the function to execute the second computer program,
acquire data showing a value of the pressure, and
calculate the flow rate by substituting the slope and the value of the pressure into the linear function to execute the first computer program,
wherein
the processing head uses a plurality of nozzles,
the storage unit stores the linear function and the function for each known nozzle among the plurality of nozzles,
the control unit is configured to calculate the flow rate when among the plurality of nozzles an unknown nozzle for which the linear function and the function are not stored is used, based on
a cross-sectional area of an opening of a known nozzle of a type same as a type of the unknown nozzle, among known nozzles for which the linear function and the function are stored in the storage unit,
a cross-sectional area of an opening of the unknown nozzle, and
the flow rate when the known nozzle of the type same as the type of the unknown nozzle is used.