Thread monitor for textile machines

A thread monitor for a sewing machine having a needle, a vertically movable presser bar and a foot adjacent the needle, said monitor comprising control means operable for stopping the operation of the machine, a thread feeler engageable with the thread supplied to the needle, and means mounting the feeler for movement between a retracted position with respect to the control means and an operative position for actuating the control means for stopping the operation of the machine, said feeler being biased toward its operative position, the bias being greater than the frictional force present between the feeler and its mounting as the machine vibrates during the operation thereof but less than the frictional force present between the feeler and its mounting when the machine is not in operation, so that, upon thread breakage when the machine is in operation, the feeler will move to its operative position for stopping the operation of the machine and, when the machine is not in operation, the feeler remains in retracted position, said thread monitor further comprising a stop movable toward and away from a position in which the stop is engageable with the feeler for preventing movement of the feeler to its operable position, the stop being mounted on the presser bar and being movable therewith toward and away from said position where the stop is engageable with the feeler.