Patent attributes
The disclosure herein discloses a rebar tying machine. The rebar tying machine may include a feed motor, a current sensor configured to detect a current flowing through the feed motor, and a control unit configured to control an operation of the feed motor. The rebar tying machine may be configured to perform: a feeding-out process in which a wire is fed out around rebars by driving the feed motor, a gripping process in which a vicinity of a tip of the wire is gripped, a pulling-back process in which the wire is pulled back by driving the feed motor, a cutting process in which the wire is cut, and a twisting process in which the wire is twisted. The control unit may be configured to determine a diameter of the rebars based on a history of a current value flowing through the feed motor in the pulling-back process.