Production of a front portion of a writing instrument, comprising a one-piece preform

A tool for one of producing and shaping a front portion of a writing instrument housing, said tool comprising

• an injection cavity into which a sleeve-shaped blank having a front opening and a radial dimension that is smaller than said injection cavity is insertable;
• an elongated core for substantially filling up said blank at an inside thereof, said core being adapted or having only a limited length such that a remaining axial length remains in front of said core or laterally at a front end thereof, said remaining axial length being delimited by said blank, up to said front opening, for guiding a softened second material supplied through said opening and for delimiting said material in a radial extension thereof.

A tool for one of producing and shaping a front portion of a writing instrument housing, wherein the tool has an injection cavity adapted to receive a sleeve shaped blank having a front opening and a radial dimension that is smaller than said injection cavity, said tool further comprising an elongated core for filling up an inside of said blank to support it, said cores having a front end said front end not fully covering a diameter of the front opening, to guide a softened material, supplied through said opening, in a radial extension thereof, by at least one portion of an inner circumference of said blank.

A method of shaping a front portion of a housing of a writing instrument, said front portion comprising a refill opening, open at a front end, for receiving and radially supporting a refill, wherein a gripping jacket is attached around a preform body, made of a shape-retaining material, said attaching between the material of said gripping jacket and the material of said preform body not being a bond of materials, and an axial portion of said refill opening serves as a walled guiding channel for the material of said gripping jacket, wherein said material is injected under pressure through said refill opening and shapes said gripping jacket on a surface of said preform body.

Tool for one of producing and shaping a front portion of a writing instrument housing, useful for providing an outer jacket on a sleeve body of shape-retaining material defining an opening for a refill and a circumferential wall with at least one aperture, including conducting a material having elastic gripping properties into an inside of the sleeve body and deflecting the material by at least one channel section in a core so as to penetrate through the aperture from inside the sleeve body, and shaping the material in an outer shaping space to build the outer jacket, said tool comprising

• an injection cavity into which a sleeve-shaped blank having a front openings and a radial dimension that is smaller than said injection cavity is insertable;
• an elongated core for substantially filling up said blank at an inside thereof, said core being adapted or having only a limited length such that a remaining axial length remains in front of said core or laterally at a front end thereof, said remaining axial length being delimited by said blank up to said front opening, for guiding a softened second material which is supplied through said openings and for delimiting said material in its radial extension.

Tool for one of producing and shaping a front section of a writing instrument housing, useful for providing an outer jacket on a sleeve body of shape-retaining material defining an opening for a refill and a circumferential wall with at least one aperture, including conducting a material having elastic gripping properties into an inside of the sleeve body and deflecting the material by at least one channel section in a core so as to penetrate through the aperture from inside the sleeve body, and shaping the material in an outer shaping space to build the outer jacket, wherein the tool has an injection cavity adapted to receive a sleeve shaped blank having a front opening and a radial dimension that is smaller than said injection cavity(41), said tool further comprising an elongated core for filling up an inside of said blank to support it, said core having a front end and being adapted at said front end such that along a remaining axial length, a diameter is smaller by an amount to guide a softened material which is supplied through said opening in its radial extension by at least one portion of an inner circumference of said blank.