Mechanism for making openings in plastic parts within a mold tool
AssigneeBuild-A-Mold Limited
InventorTony Romanello
Life of this patent
Estimating the term…
Abstract
An assembly disposed within a mold for forming openings in a plastic part includes a punch pin and a backing pin having faces disposed flush with a surface of a mold cavity. The backing pin is disposed opposite the punch pin. The punch pin is driven into the completed plastic part removing material to form an opening. The waste material is driven into a bore housing the backing pin. The backing pin recedes into the bore to accept the waste material. Upon ejection of the plastic part the waste material ejects from the mold cavity as the backing pin moves back to a position flush with the surface of the mold cavity.
Claims16
A method of forming an opening in a molded plastic part within a mold tool comprising the steps of:
- a. introducing plastic into a mold cavity defined by a first mold part and a second mold part movable relative to each other in a first pull direction to form the plastic part;
- b. locking a backing pin and a punch pin in a locking position such that a face of the backing pin and the punch pin are flush to a surface of the mold cavity during molding of the plastic part;
- c. unlocking the backing pin after said plastic part has solidified;
- and
- d. driving the punch pin through said solidified plastic part in a second direction different from said first pull direction forming the desired opening.
A method of forming an opening in a molded plastic article within a mold tool comprising the steps of:
- a) introducing plastic material in a molten state into a mold cavity defined by a first mold part and a second mold part, wherein an interface between said first mold part and said second mold part defines a parting line;
- b) solidifying the plastic material to form the plastic article;
- c) unlocking a backing pin only after said plastic material has solidified;
- and
- d) driving a punch pin through the solidified plastic article in a direction not normal to said parting line to form a desired opening.
A method of forming an opening in a molded plastic article within a mold tool comprising the steps of:
- a) introducing a plastic material into a cavity defined by at least a first mold part and a second mold part through an inlet channel;
- b) locking a backing pin and a punch pin in place such that a face surface of each of the backing pin and the punch pin is flush with a surface of the cavity;
- c) solidifying the plastic material to form the plastic article;
- d) unlocking the backing pin spaced apart from said inlet channel;
- and
- e) driving the punch pin through the solidified plastic article, wherein said punch pin is disposed within said mold on an opposite side of said backing pin spaced apart from said inlet channel,
- wherein the at least first mold part and second mold part separate from each other along a pull axis that is different from the axis of movement of the punch pin.
Dependencies are inferred from the claim text.