Condition measuring device that measures the condition of a
cutting tool (200) during a
cutting operation, wherein the
cutting tool (200) consists of a rotating body having one or more blade sections (202) and bringing each of the blade sections (202) into contact with a workpiece (W) during rotation in order to
machine the workpiece (W), wherein the condition measuring device comprises: one or more measuring sections (101) attached to the blade section (202) or to a surrounding area of the blade section to measure a condition of the blade section (202); an AD converter (103) attached to the
cutting tool to obtain a measured value measured through each of the measuring sections at a predetermined sampling rate and to perform an AD conversion with respect to the measured value; a transmission section (105) which transmits the measured value from the A / D converter (103) using digital
wireless communication each time the measured value is obtained; and a monitor device (120) which is provided outside the
cutting tool, wherein the monitor device (120) comprises: a receiving section (122) that receives the measured value transmitted by the transmitting section (105); and a
data management section (124) that causes a display section (126) to display the measured value, and a storage section (127) that causes the measured value to be stored each time the measured value is received by the receive section (122), wherein each of the measuring sections (101) comprises a
strain gauge or a piezoelectric element, and the amplitudes of the measured values are recorded by the
strain gauge or the piezoelectric element from the chronological data of the measured values received by the receiving section (122), and a difference is obtained between each of the recorded amplitudes and a reference value, and wherein the condition measuring device further comprises an
abnormality detection section (125) which determines that an
abnormality has occurred in the blade section (202) if the difference is greater than a
reference distance value, and, when the presence of the
abnormality is determined, displays information showing the occurrence of the abnormality on the display section (126).