Method for diagnosing state of rolling guide device

A state diagnosis method for a rolling guide device,

• the rolling guide device including:
• a track member having a rolling surface extending along a longitudinal direction of the track member;
• and
• a moving member, which is assembled to the track member through intermediation of a plurality of rolling elements configured to roll on the rolling surface so that the moving member is movable along the track member, and has an endless circulation path for the rolling elements,
• the state diagnosis method comprising:
• detecting a moving speed of the moving member relative to the track member while detecting relative vibration displacement of the moving member relative to the track member using a vibration sensor mounted to the moving member;
• diagnosing a running state of the moving member relative to the track member based on those detection results;
• comparing, after a threshold value of the vibration displacement of the moving member is determined based on the moving speed of the moving member, a detection signal from the vibration sensor and the threshold value;
• determining, when the detection signal from the vibration sensor is larger than the threshold value, that there is an abnormality in the running state of the moving member relative to the track member;
• supplying, when an abnormality in the running state of the moving member relative to the track member is determined, lubricant to the rolling guide device;
• reading out the detection signal from the vibration sensor to determine the threshold value again after the supply of the lubricant is completed;
• and
• determining, when the detection signal from the vibration sensor is larger than the threshold value after the supply of the lubricant is completed, that there is a defect in the supply of the lubricant or a defect in the rolling surface of the track member.