DEVICE TO ELECTROMAGNETICALLY BRAKE AT LEAST ONE THREAD FEEDING BOBBIN WHICH IS ROTATABLE SUPPORTED ON HOLLOW SHAFT,AND CONNECT SAID BOBBIN

PROBLEM TO BE SOLVED: To unravel a stranded type of material from a yarn feed bobbin for electromagnetically braking and jointing at least one yarn feed bobbin rotatably journalled on a hollow shaft around a lengthwise axial line, and wind the strandard type of material around the yarn feed bobbin at the time of the jointing thereof to the driven hollow shaft. SOLUTION: A support part 31 of approximate start shape having many holding devices 37 radially projected outside and dispersed peripherally are provided on and secured to a hollow shaft 5, and at least one electrically excited magnet coil 45 is held with the holding devices 37 at radial gaps over a distance up to the hollow shaft 5. The device so formed is used for electromagnetically braking and jointing at least one yarn feed bobbin journalled on the hollow shaft 5 for rotation around a lengthwise axial line, and can be easily and inexpensively manufactured, even when the outer diameter of the hollow shaft 5 is large.