Cutting system, display system, processing apparatus, processing method, and processing program
A cutting system includes a cutting tool for milling, a plurality of sensors, and a processor, wherein the cutting tool performs a cutting process using two or more cutting blades, the plurality of sensors measure a physical quantity indicating a state regarding a load of the cutting tool at a time of the cutting process, and the processor generates, based on measurement results of the sensors at a plurality of measurement timings, two-dimensional data for each measurement timing, the two-dimensional data regarding the load in two directions on a plane perpendicular to a rotation axis of the cutting tool, classifies pieces of the generated two-dimensional data into any of a plurality of unit regions, a number of which is equal to or greater than a number of the cutting blades on the plane, and detects, based on the two-dimensional data for each unit region, an abnormality of the cutting blade.
1 . A cutting system comprising:
a cutting tool for performing a cutting process, the cutting tool including:
a shank having a blade attaching portion, the blade attaching portion including a plurality blade fixing portions;
a plurality of strain sensors attached to the shank, the plurality of strain sensors being for measuring strain of the shank;
a memory sequentially storing measurement results obtained by the plurality of sensors during the cutting process by the cutting tool; and
processing circuitry detecting an abnormality of at least one of a plurality of cutting blades attached to each of the plurality of blade fixing portions by repeatedly executing a process including the following (a)-(d) by accessing the memory during the cutting process by the cutting tool, wherein
the processing circuitry is configured to:
(a) generate, based on the measurement results obtained by each of the plurality of strain sensors at a plurality of measurement timings by accessing the memory, two-dimensional data for each of the measurement timings, the two-dimensional data regarding the load in multiple directions on a plane intersecting the rotation axis,
(b) classify pieces of the generated two-dimensional data into any of a plurality of unit regions, a number of which is greater than or equal to a number of the plurality of cutting blades on the plane,
(c) calculate an index value based on the two-dimensional data of each of the plurality of unit regions, including calculating a moving standard deviation of a distance from an origin of the two-dimensional data for each unit region, and
(d) detect, based on the calculated the moving standard deviation for each unit region, an abnormality of at least one of the plurality of cutting blades, including:
determining that an increase in the moving standard deviation is not caused by the abnormality of at least one of the plurality of cutting blades when all the moving standard deviations are increased,
determining that an increase in the moving standard deviation is caused by the abnormality of at least one of the plurality of cutting blades when not all the moving standard deviations are increased.
2 . The cutting system according to claim 1 , wherein the processing circuitry classifies the pieces of the two-dimensional data into any of the unit regions, the number of which is equal to the number of the plurality of cutting blades.
3 . The cutting system according to claim 1 , wherein the processing circuitry sequentially generates and classifies the two-dimensional data, and detects, based on the number of the unit regions, for which a temporal change of the two-dimensional data is greater than or equal to a predetermined value, the abnormality of the plurality of cutting blades.
4 . The cutting system according to claim 1 , wherein a number of the plurality of strain sensors is irrelevant to the number of the plurality of cutting blades in the cutting tool.
5 . The cutting system according to claim 1 , wherein a number of the plurality of strain sensors is less than the number of the plurality of cutting blades in the cutting tool.
6 . The cutting system according to claim 1 , wherein the plurality of blade fixing portions are provided at positions shifted by 90 ° in a clockwise direction in a circumferential direction of the blade attaching portion.
7 . The cutting system according to claim 1 , wherein each of the plurality of cutting blades is an indexable insert, and
wherein each of the plurality of cutting blades is fixed to a respective one of the plurality of blade fixing portions by a screw.
8 . The cutting system according to claim 1 , further comprising:
a housing covering the plurality of strain sensors from below and from a side;
a battery disposed in the housing; and
a wireless communication apparatus disposed in the housing, the wireless communication apparatus including a communication circuit.
9 . The cutting system according to claim 8 , wherein the battery is connected to the plurality of strain sensor and to the wireless communication apparatus.
10 . The cutting system according to claim 8 , wherein the wireless communication apparatus performs analog-to-digital (AD) conversion on an analog signal received from the plurality of strain sensors at a predetermined sampling period.
11 . The cutting system according to claim 10 , wherein the wireless communication apparatus adds a time stamp indicating a sampling timing to each of the generated sensor measurement values and stores the generated sensor measurement values in a storage unit, the storage unit being nonvolatile memory.
12 . The cutting system according to claim 1 , wherein the circuitry is further configured to:
display a first diagram including the moving standard deviation for each unit region on a vertical axis of the first diagram and time on a horizontal axis of the first diagram, and
calculate an average value of the moving standard deviation, and
display a second diagram including the average value of the moving standard deviations on a vertical axis of the second diagram and time on a horizontal axis of the second diagram.
13 . The cutting system according to claim 12 , wherein the circuitry is further configured to:
calculate a moving standard deviation difference between each moving standard deviation of each unit region and the average value of the moving standard deviations of each unit region, and
display a third diagram including each moving standard deviation difference on a vertical axis of the third diagram and time on a horizontal axis of the third diagram.