US 12,485,564 B2
Active safety apparatus for a disc cutter
Keith Blenkinsopp, Auckland (NZ); and George Davey Maddever, Auckland (NZ)
Assigned to KANDO INNOVATION LIMITED, Auckland (NZ)
Appl. No. 18/558,341
Filed by KANDO INNOVATION LIMITED, Auckland (NZ)
PCT Filed Aug. 4, 2022, PCT No. PCT/NZ2022/050100
§ 371(c)(1), (2) Date Oct. 31, 2023,
PCT Pub. No. WO2023/014232, PCT Pub. Date Feb. 9, 2023.
Claims priority of application No. 778784 (NZ), filed on Aug. 4, 2021.
Prior Publication US 2024/0227230 A1, Jul. 11, 2024
Int. Cl. B26D 7/24 (2006.01); B26D 1/14 (2006.01); B26D 5/00 (2006.01)
CPC B26D 7/24 (2013.01) [B26D 1/14 (2013.01); B26D 5/007 (2013.01); B26D 2210/02 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A power-driven disc cutter configured for cutting a workpiece, the cutter comprising:
a frame;
an arbor attached to the frame;
a supporting shaft supported in the arbor
a rotatable disc blade with a cutting edge held on the supporting shaft;
a controllable motor connected to rotate the supporting shaft;
a safety apparatus operatively connected to the controllable motor, the safety apparatus comprising an optical imaging portion connected to the frame, the optical imaging portion being configured to sense a gloved hand within an exclusion volume that includes the cutting edge, the optical imaging portion comprising:
a single camera having an image sensor chip;
a lens aligned with the sensor chip and positioned to focus incoming light onto the sensor chip;
four sets of mirrors arranged to project, respectively, four separate views of the exclusion volume, each of the four sets of mirrors comprising:
a first mirror configured to reflect a corresponding one of the four separate views toward an optical axis of the lens; and
a second mirror configured to receive the corresponding one of the four separate views reflected by the first mirror and reflect the corresponding one of the four separate views along a respective one of four separate optical axes passing through the lens;
wherein the optical imaging portion is configured so that each of the four separate views of the exclusion volume is focused on a respective one of four separate, non-overlapping portions of a surface of the image sensor chip; and
wherein each of the four separate optical axes associated with the four second mirrors defines a corner edge of the exclusion volume, the exclusion volume having a shape of either a right frustrum or a cuboid.