Apparatus for lifting a wound yarn package

An apparatus for lifting a wound yarn package having an outer surface from a drive roll serving for the drive thereof on a textile machine, comprising:

• a package support member for lifting and supporting the yarn package;
• said package support member being provided with a package contact region for contacting the yarn package at an outer surface thereof;
• means cooperating with said package support member for moving said package contact region into a package lifting position against a portion of the outer surface of the yarn package during a yarn package lift-off movement;
• said means for moving the package support member comprising a piston-and-cylinder unit composed of a cylinder and a piston reciprocatable within said cylinder;
• said piston being provided with a piston rod connected at an end thereof remote from the piston with said package support member;
• means for subjecting said piston to a drive force in order to accomplish the yarn package lift-off movement;
• means for returning the package support member into an initial position by applying a return force which is small relative to the drive force produced by said subjecting means;
• said piston, said piston rod and said cylinder of said piston-and-cylinder unit coacting with one another such that a pressure of the wound yarn package upon said forward package contact region produces a tendency to rotate said piston and said piston rod within said cylinder in a plane extending substantially perpendicular to the lengthwise axis of the wound yarn package;
• said cylinder coacting with said piston and said piston rod to produce forces countering said tendency to rotate;
• and
• said forces overriding said continually operative return force and thereby restraining said package support member in said package lifting position.

An apparatus for lifting a wound yarn package having an outer surface and a lengthwise axis from an initial position in which the wound yarn package is in operative engagement with a drive roller of a textile machine into package lifting position in which the wound yarn package is disengaged and remote from the drive roller, such apparatus comprising:

• a package support member for lifting the wound yarn package into the package lifting position and supporting the wound yarn package in the package lifting position for a desired length of time;
• the outer surface of the wound yarn package having a lower region;
• said package support member having a forward end;
• said package support member comprising a package contact region arranged at said forward end and extending substantially parallel to the lengthwise axis of the wound yarn package for contacting said lower region of the wound yarn package;
• a piston rod having a first predetermined outside diameter, said piston rod being rigidly united with said package support member and extending in a direction substantially parallel to said package support member;
• a piston having a second predetermined outside diameter, said piston being rigidly united with said piston rod arranged substantially coaxial with said piston rod;
• a cylinder having a first predetermined inside diameter greater than said second predetermined outside diameter by a first predetermined small amount for accommodating said piston with play;
• said cylinder being rigidly secured to the textile machine and defining a displacement path for said piston, said piston rod and said package support member;
• said displacement path extending in a direction transverse to the lengthwise axis of the wound yarn package and between the drive roller and the lengthwise axis of the wound yarn package;
• said cylinder comprising guide means having a second predetermined inside diameter greater than said first predetermined outside diameter by a second predetermined small amount for accommodating said piston rod with play;
• said cylinder having a first end remote from the wound yarn package and the drive roller;
• said cylinder having a second end located between said first end and the wound yarn package and the drive roller and remote from said first end by a predetermined stroke length;
• said guide means being arranged at said second end;
• said piston having a first position within said cylinder near said first end and in which said piston rod and said package support member are retracted in relation to the wound yarn package and the drive roller;
• said piston having a second position within said cylinder near said second end and in which said piston rod and said package support member are advanced in relation to the wound yarn package and the drive roller such that said package support member engages said lower region of the wound yarn package and lifts the wound yarn package from the initial position to the package lifting position and supports the wound yarn package in the package lifting position;
• means for reciprocating said piston between said first position and said second position;
• and
• said first predetermined small amount of play, said second predetermined small amount of play and said predetermined stroke length being interrelated such that said piston and said piston rod are freely moveable in said cylinder when said piston is in said first position and when said piston is at a location intermediate said first position and said second position and such that said piston and said piston rod assume a canted orientation substantially immobilizing said piston and said piston rod when said piston is at least substantially in said second position and said package support member is supporting the wound yarn package in the package lifting position.