Component mounting machine and contact determination method

A contact determination method to be applied to a component mounter that includes a head including multiple holders each relatively and movably holding a nozzle and sequentially performs mounting operations of mounting components picked up by multiple nozzles on a board, the component mounter including a fluid pressure circuit connected to the multiple holders and a sensor configured to detect at least one of a pressure and a flow rate of a fluid flowing through the fluid pressure circuit, the contact determination method being for determining whether the component picked up by the nozzle is in contact with the board, the contact determination method comprising:

• setting a threshold such that the threshold increases as an absolute value of a pressure or a flow rate detected by the sensor at a predetermined timing increases;
• and
• determining that the component picked up by the nozzle is in contact with the board when the absolute value of the pressure detected by the sensor, an absolute value of a change amount of the detected pressure, or an absolute value of the detected flow rate or a change amount of the detected flow rate exceeds the threshold during the mounting operation after the predetermined timing.