Nozzle attachment for an adhesive dispensing device

A nozzle attachment for use in an apparatus for dispensing adhesive which includes a gun body having a nozzle formed with an adhesive passageway for conveying adhesive and an air delivery passageway for conveying pressurized air, said nozzle attachment comprising:

• an annular plate formed with a first surface on one side of said plate, and a second surface on an opposite side of said plate;
• a nozzle tip formed in said plate which extends inwardly from said second surface toward said first surface, said nozzle tip having an outer surface and a discharge outlet located in substantially the same plane as said second surface of said plate;
• said plate being formed with a throughbore extending between said first surface and said discharge outlet of said nozzle tip, said plate being adapted to mount to said nozzle of said gun body so that said throughbore communicates with said adhesive passageway in said nozzle for receiving adhesive, the adhesive being transmitted through said throughbore and being ejected from said discharge outlet of said nozzle tip to form an adhesive bead;
• said plate being formed with a first annular groove extending inwardly from said second surface toward said first surface, said first annular groove having a first portion which forms said outer surface of said nozzle tip and a second portion which slopes relative to said throughbore in said plate, said plate being formed with a second annular groove extending inwardly from said first surface toward said second surface;
• said plate being formed with a plurality of air jet bores extending through said plate having an inlet at said second annular groove and an outlet at said first annular groove, said plate being adapted to mount to said nozzle so that said inlet of each said air jet bores communicates with said air delivery passageway in said nozzle for transmitting air therethrough, said air jet bores each having a longitudinal axis extending substantially perpendicular to said second portion of said first annular groove, said air jet bores being formed at an angle with respect to said throughbore in said plate to direct pressurized air flowing therethrough substantially tangent to the outer periphery of said adhesive bead ejected from said adhesive discharge outlet of said nozzle tip to form said adhesive bead in an elongated adhesive fiber and to impart a twisting motion to said elongated adhesive fiber for deposition in a spiral spray pattern on a substrate.

Apparatus for spraying hot melt adhesive, comprising:

• a gun body having a nozzle formed with an adhesive passageway communicating with a source of adhesive and an air passageway communicating with a source of pressurized air;
• a plate formed with a boss extending outwardly from a first surface of said plate and a nozzle tip extending inwardly from a second surface of said plate toward said first surface, said nozzle tip having an outer surface and a discharge outlet located in substantially the same plane as said second surface of said plate, said plate being formed with a throughbore extending between said boss and said discharge outlet of said nozzle tip;
• said plate being formed with an annular groove extending inwardly from said second surface toward said first surface, said annular groove having a first portion which forms said outer surface of said nozzle tip and a second portion which slopes relative to said throughbore in said plate;
• said plate being formed with a plurality of air jet bores extending from said annular groove through said plate, said air jet bores each having a longitudinal axis extending substantially perpendicular to said second portion of said annular groove and at an angle relative to the longitudinal axis of said throughbore in said plate;
• cap means for mounting said plate to said nozzle of said gun body so that said throughbore formed between said boss and said discharge outlet in said nozzle tip communicates with said adhesive passageway in said nozzle and so that said air jet bores communicate with said air passageway in said nozzle, said throughbore receiving adhesive from said adhesive passageway and ejecting the adhesive from said discharge outlet in said nozzle tip to form an adhesive bead, said air jet bores receiving pressurized air from said air passageway in said nozzle and directing the pressurized air substantially tangent to the outer periphery of said adhesive bead to form an elongated adhesive fiber and to impart a twisting motion to said elongated adhesive fiber to form a spiral spray pattern of the elongated adhesive fiber for deposition on a substrate.

Apparatus for spraying hot melt adhesive, comprising:

• a gun body having a nozzle formed with an adhesive passageway communicating with a source of adhesive and an air passageway communicating with a source of pressurized air;
• a plate formed with a boss extending outwardly from a first surface of said plate and a nozzle tip extending inwardly from a second surface of said plate toward said first surface, said nozzle tip having an outer surface and a discharge outlet located in substantially the same plane as said second surface of said plate, said plate being formed with a throughbore extending between said boss and said discharge outlet of said nozzle tip;
• said plate being formed with a first annular groove extending inwardly from said second surface toward said first surface, said first annular groove having a first portion which forms said outer surface of said nozzle tip and a second portion which slopes relative to said throughbore in said plate, said plate being formed with a second annular groove which extends inwardly from said first surface toward said second surface;
• said plate being formed with a plurality of air jet bores extending through said plate having an inlet at said second annular groove and an outlet at said first annular groove, said air jet bores each having a longitudinal axis extending substantially perpendicular to said second portion of said first annular groove and at an angle relative to the longitudinal axis of said throughbore in said plate;
• cap means for mounting said plate to said nozzle of said gun body so that said throughbore formed between said boss and said discharge outlet in said nozzle tip communicates with said adhesive passageway in said nozzle and so that said second annular groove and said air jet bores communicate with said air passageway in said nozzle, said throughbore receiving adhesive from said adhesive passageway and ejecting the adhesive from said discharge outlet in said nozzle tip to form an adhesive bead, said air jet bores receiving pressurized air from said air passageway in said nozzle through said second annular groove and directing the pressurized air substantially tangent to the outer periphery of said adhesive bead to form an elongated adhesive fiber and to impart a twisting motion to said elongated adhesive fiber to form a spiral spray pattern of the elongated adhesive fiber for deposition on a substrate.