Control device for threading tubes in crochet galloon looms

A control device for threading tubes in crochet galloon looms, comprising:

• a thread guide rail provided with an oscillatory motion;
• a number of threading tubes oscillatably supported by the thread guide rail and individually translatable with respect to said rail against the action exerted by respective first return springs;
• a number of actuation cables each of them having one end connected to one of said threading tubes;
• a number of sheaths each slidably engaging one of said actuation cables and having one end fixedly fastened with respect to the thread guide rail and the second end engaged with a fixed support;
• a number of control plates each engaging at least one of said actuation cables at a second end thereof and being provided with a to-and-fro translation movement with respect to said fixed support in order to cause, through said actuation cables, the translations of said threading tubes against the action of said first return springs;
• control means to selectively translate the control plates in synchronism with the movements of said thread guide rail,
• which device further comprises a number of second return springs each of them having a greater stiffness than the first return springs and acting between a shoulder formed in said fixed support and a locating element fastened to the second end of one of said sheaths, the length of each sheath being greater than the distance between the opposed ends thereof.