Thermoplastic block shape, feeding mechanism and manufacturing method

A device adapted for dispensing molten, thermoplastic material from a block of the solid thermoplastic material comprising coaxial generally cylindrical portions of uniform predetermined axial and diametrical dimensions uniformly axially spaced along the block by rectangular portions having diagonal dimensions about equal to said diametrical dimension, said device comprising a frame including a handle positioned so that an operator can grip the handle with the fingers of one hand;

• a barrel member mounted on said frame and having an internal melting chamber communicating with an outlet opening through a nozzle;
• a sleeve with a through opening having one end secured to said barrel member with said through opening communicating with the end of said melting chamber opposite said outlet opening, said sleeve being adapted to receive a said block of solid thermoplastic material with one end portion of the block in the melting chamber and the block projecting through said sleeve;
• means for heating said barrel member to melt the end portion of the block therein;
• and a feeding mechanism at the end of said sleeve opposite said melting chamber comprising wall means fixed to said frame and defining a passageway adapted to guide the solid thermoplastic material block in alignment with the through opening in said sleeve, a slide having an upper surface positioned adjacent said passageway, and being mounted on said frame for movement along a path generally aligned with the melting chamber from a retracted position spaced from said sleeve to an advanced position more closely adjacent the sleeve and back to said retracted position, drive means carried by said slide adapted for engaging said cylindrical portions and advancing the block of thermoplastic material toward the melting chamber during movement of said slide from its retracted to its advanced position, and for moving around the cylindrical portions and along the block of thermoplastic during movement of said slide from its advanced to its retracted position, means for aligning the block of thermoplastic in said passageway for engagement by said drive means, and means projecting from the side of said slide opposite said upper surface in a direction generally at a right angle to said upper surface including a first projecting part adjacent said sleeve and a second projecting part spaced from the side of said first projecting part opposite said sleeve for defining a recess between said first and second parts adapted to receive the end portion of the thumb of an operator gripping said handle to afford manual movement of said slide both toward said advanced position and toward said retracted position.

A feeding mechanism adapted for use on a device for dispensing molten, thermoplastic material from a block of the solid thermoplastic material comprising coaxial generally cylindrical portions of uniform predetermined axial and diametrical dimensions uniformly axially spaced along the block by rectangular portions having diagonal dimensions about equal to said diametrical dimension, said device comprising a frame including a handle positioned so that an operator can grip the handle with the fingers of one hand;

• a barrel member mounted on said frame and having an internal melting chamber communicating with an outlet opening through a nozzle;
• a sleeve with a through opening having one end secured to said barrel member with said through opening communicating with the end of said melting chamber opposite said outlet opening, said sleeve being adapted to receive the block of solid thermoplastic material with one end portion of the block in the melting chamber and the block projecting through said sleeve;
• and means for heating said barrel member to melt the end portion of the block therein;
• said feeding mechanism comprising wall means adapted to be attached to said frame at the end of said sleeve opposite said melting chamber and defining a passageway adapted to guide the solid thermoplastic material block in alignment with the through opening in said sleeve;
• a slide having an upper surface adapted to support the block and being mounted on said frame for movement along a path generally aligned with the melting chamber from a retracted position spaced from said sleeve to an advanced position more closely adjacent the sleeve and back to said retracted position;
• drive means carried by said slide adapted for engaging said cylindrical portions and advancing the block of thermoplastic material toward the melting chamber during movement of said slide from its retracted to its advanced position, and for moving around the cylindrical portion and along the block of thermoplastic during movement of said slide from its advanced to its retracted position;
• means for aligning the block of thermoplastic in said passageway for engagement by said drive means;
• and means projecting from the side of said slide opposite said upper surface in a direction generally at a right angle to said upper surface including a first projecting part adjacent said sleeve and a second projecting part spaced from the side of said first projecting part opposite said sleeve for defining a recess between said first and second parts adapted to receive the end portion of the thumb of an operator gripping said handle to afford manual movement of said slide both toward said advanced position and toward said retracted position.