Yarn tension device for a flat knitting machine

A yarn tension device for a flat knitting machine, comprising a yarn brake having first and second juxtaposed brake plates, said brake plates being adapted to receive a yarn therebetween, biassing means urging at least one of the brake plates towards the other brake plate, and a securing device which defines a yarn path between said brake plates, said securing device being capable of being opened to permit the yarn to be open-threaded into said yarn path but being operative thereafter to close automatically access to said yarn path.