Thermoplastic block shape, feeding mechanism and manufacturing method

Claim 2

In combination, a block of 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; and a device for dispensing molten thermoplastic material from said block 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 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 one side of 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 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 body toward said advanced position and toward said retracted position.

Claim 3

A combination according to claim 1 wherein said rectangular portions are square in cross section.

Claim 4

A combination according to claim 1 wherein said means for aligning comprises a sprocket having teeth spaced to engage between said cylindrical portions along corresponding sides of said rectangular portions, said sprocket being mounted on said wall means on the side of said passageway opposite said drive means for rotation about an axis disposed transverse of said passageway.

Claim 5

A combination according to claim 1 wherein said drive means comprises an elongate drive member having a plurality of teeth adapted to engage between the cylindrical portions of the block, said teeth projecting from one side of said drive member adjacent a first end of said drive member, said drive member being oriented on said slide with its longitudinal direction generally parallel to said passageway and said teeth adjacent said sleeve and having a second end opposite said first end mounted on said slide both for pivotal movement of said drive member relative to said slide between an engage position with said teeth in engagement between cylindrical portions of said block in said passageway and a release position with the teeth spaced from the block in the passageway, and for longitudinal movement relative to said slide between a normal position and a locked position with said teeth farther from said sleeve with respect to the same position of said slide when said drive member is in said normal position; means adapted for engagement between said slide and said drive member to prevent pivotal movement of said drive member away from said engage position when said drive member is in said locked position and to afford movement of said drive member from said engage position to said release position when said drive member is in said normal position, and a spring between said slide and said drive member for biasing said drive member to said normal and engage positions, said drive member having a projection projecting into said recess and manually engageable to pivot said drive member to said release position when said slide is manually moved toward said retracted position.

Claim 6

A combination according to claim 4 wherein said teeth have cam surfaces on their sides opposite said sleeve adapted to cam said teeth around said cylindrical portions of said block by pivoting said drive member toward said release position when said slide is manually moved from said advanced position toward said retracted position.

Claim 9

A device according to claim 6 wherein said means for aligning comprises a sprocket having teeth spaced to engage between said cylindrical portions along corresponding sides of said rectangular portions, said sprocket being mounted on said wall means on the side of said passageway opposite said drive means for rotation about an axis disposed transverse of said passageway.

Claim 10

A device according to claim 6 wherein said drive means comprises an elongate drive member having a plurality of teeth adapted to engage between the cylindrical portions of the block, said teeth projecting from one side of said drive member adjacent a first end of said drive member, said drive member being oriented on said slide with its longitudinal direction generally parallel to said passageway and said teeth adjacent said sleeve and having a second end opposite said first end mounted on said slide both for pivotal movement of said drive member relative to said slide between an engage position with said teeth in engagement between cylindrical portions of a said block in said passageway and a release position with the teeth spaced from the block in the passageway, and for longitudinal movement relative to said slide between a normal position and a locked position with said teeth farther from said sleeve with respect to the same position of said slide when said drive member is in said normal position; means adapted for engagement between said slide and said drive member to prevent pivotal movement of said drive member away from said engage position when said drive member is in said locked position and to afford movement of said drive member from said engage position to said release position when said drive member is in said normal position, and a spring between said slide and said drive member for biasing said drive member to said normal and engage positions, said drive member having a projection projecting into said recess and manually engageable to pivot said drive member to said release position when said slide is manually moved toward said retracted position.

Claim 11

A device according to claim 8 wherein said teeth have cam surfaces on their sides opposite said sleeve adapted to cam said teeth around the cylindrical portions of a said block by pivoting said drive member toward said release position when said slide is manually moved from said advanced position toward said retracted position.

Claim 12

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.

Claim 13

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.

Claim 14

A feeding mechanism according to claim 10 wherein said means for aligning comprises a sprocket having teeth spaced to engage between said cylindrical portions along corresponding sides of said rectangular portions, said sprocket being mounted on said wall means on the side of said passageway opposite said drive means for rotation about an axis dispsoed transverse of said passageway.

Claim 15

A feed mechanism according to claim 10 wherein said drive means comprises an elongate drive member having a plurality of teeth adapted to engage between the cylindrical portions of the block, said teeth projecting from one side of said drive member adjacent a first end of said drive member, said drive member being oriented on said slide with its longitudinal direction generally parallel to said passageway and said teeth adjacent a said sleeve and having a second end opposite said first end mounted on said slide both for pivotal movement of said drive member relative to said slide between an engage position with said teeth in engagement between cylindrical portions of a said block in said passageway and a release position with the teeth spaced from the block in the passageway, and for longitudinal movement relative to said slide between a normal position and a locked position with said teeth farther from the sleeve with respect to the same position of said slide when said drive member is in said normal position; means adapted for engagement between said slide and said drive member to prevent pivotal movement of said drive member away from said engage position when said drive member is in said locked position and to afford movement of said drive member from said engage position to said release position when said drive member is in said normal position, and a spring between said slide and said drive member for biasing said drive member to said engage and normal positions, said drive member having a projection projecting into said recess and manually engageable to pivot said drive member to said release position when said slide is manually moved toward said retracted position.

Claim 16

A feed mechanism according to claim 12 wherein said teeth have cam surfaces on their sides opposite the sleeve adapted to cam said teeth around the cylindrical portions of a said block by pivoting said drive member toward said release position when said slide is manually moved from said advanced position toward said retracted position.