Unit drafting mechanism having air jet apertured slide metals and rollers

A unit drafting mechanism of a spinning machine provided with at least one unit drafting mechanism, wherein a pair of slide metals are disposed on roller stands facing each other, a plurality of bottom rollers and top rollers are journaled on said slide metals in a rotatable condition, each one of said bottom rollers provided with a fluted working section of a length substantially corresponding to a distance between inside surfaces of said slide metals, a pair of journal portions are rotatably supported by said slide metals, and a pair of shoulder portions, each thereof provided with an intermittent portion between a corresponding end portion of said fluted working section and a corresponding one of said journal portions, comprising:

• a cylindrical recess formed at an inside position of each one of said slide metals for receiving a corresponding shoulder portion of said bottom roller with an annular gap therebetween,
• an axial air passage formed along an axis center of each said bottom roller,
• at least one air jet aperture radially formed at each of said shoulder portions thereof in a direction facing said gap between said cylindrical recess and said shoulder portion, each one of said air jet apertures connected to said axial air passage,
• a compressed air supply source to supply compressed air to said axial air passage of each one of said bottom rollers, and
• means for connecting said compressed air supply source to said axial air passage of each one of said bottom rollers.