Process and apparatus for positioning a series of roving bobbin carriages in a yarn manufacturing spinning machine

An apparatus for precisely positioning full roving bobbins opposite respective working positions to be fed with roving of a yarn-manufacturing spinning machine having a multiplicity of said working positions spaced apart longitudinally in a rectilinear direction along said machine, said apparatus comprising:

• a rail extending along said machine in said direction above a level of the working positions thereof;
• a plurality of bobbin carriages shiftable along said rail each having a respective engagement member fixed thereon;
• a plurality of full roving bobbins, lesser in number than that of the positions of said machine, suspended from each bobbin carriage with a spacing between said bobbins corresponding to a spacing of said positions from one another along said machine;
• for each group of working positions equal in number to a number of working positions capable of being serviced by the roving bobbins suspended from each carriage, at least one movable locking element fixedly positioned with respect to a region of said machine provided with the respective group and actuated from a location alongside the path of the carriages along the rail to positively and form-fittingly engage a respective member and immobilize the respective carriage so that all of the roving bobbins of the respective immobilized carriage are simultaneously precisely positioned opposite respective working positions at said region;
• and
• means for displacing said carriages along said rail.