Molding process for forming complex shapes
AssigneeHonda Engineering North America
InventorsYuichi Uchiyama, Lam B. Sam
Life of this patent
Estimating the term…
Abstract
A plastic part having a complex structure as a first layer and a simple structure as a second layer, is formed using a method for molding. Initially, a single mold is provided, the mold having an interior cavity and a runner reaching from an exterior of the mold to the cavity. The mold is kept closed while a quantity of a first plastic material is injected via the runner into the interior cavity to form a first layer of the plastic part. The mold is then partially opened, creating an increased interior cavity section, into which a quantity of a second plastic material is injected, via the runner, to form a second layer of the plastic part. The solidified plastic part can then be ejected from the mold.
Claims20
For forming a plastic part having a complex structure as a first layer and a smooth structure as a second layer, a method for molding comprising the steps of:
- providing a single mold, the mold having an interior cavity and a runner reaching from an exterior of the mold to the cavity;
- closing the mold;
- injecting a quantity of a first plastic material via the runner into the interior cavity while maintaining pressure on the mold to maintain the mold in its closed state to form a complex structure as a first layer of the plastic part, wherein the appearance of the complex structure is non-critical;
- partially opening the mold to create an increased interior cavity section;
- injecting a quantity of a second plastic material via the runner and into the increased interior cavity section while maintaining the mold in its partially open state;
- closing the mold and applying clamping force to the mold to compress the second plastic material and thereby form a smooth structure as a second layer of the plastic part, wherein the complex structure provides strength to the smooth structure;
- and
- ejecting the plastic part.
For forming a plastic part, a method for molding comprising the steps of:
- providing a single mold, the mold having an interior cavity and a runner reaching from an exterior of the mold to the cavity;
- closing the mold;
- injecting a quantity of a first plastic material via the runner into the interior cavity while maintaining pressure on the mold to maintain the mold in its closed state to form a complex layer of the plastic part, the complex layer having a non-critical appearance and capable of providing strength to the plastic part, and whereby a metal-to-plastic shear edge is established during injection of the first plastic part;
- partially opening the mold to create an increased interior cavity section;
- injecting a quantity of a second plastic material via the runner and into the increased interior cavity section while maintaining pressure on the mold to maintain the mold in its partially open state;
- closing the mold and applying clamping force to the mold to compress the second plastic material and thereby form a smooth layer of the plastic part;
- and
- ejecting the plastic part.
For forming a plastic part having a complex structure as a first layer and a smooth structure as a second layer, a method for molding comprising the steps of:
- providing a single mold, the mold having an interior mold cavity and a mold core reaching from an exterior of the mold to the cavity;
- closing the mold;
- forming a first shear edge for a first injection by securely abutting the mold cavity against the mold core;
- injecting a quantity of a first plastic material via the mold core into the mold cavity while maintaining pressure on the mold in its closed state to form a complex structure as a first layer of the plastic part, wherein the appearance of the complex structure is non-critical;
- partially opening the mold to create an increased interior mold cavity section;
- injecting a quantity of a second plastic material via the mold core and into the increased interior mold cavity section while maintaining pressure on the mold to maintain the mold in its partially open state;
- closing the mold and applying clamping force to the mold to compress the second plastic material and thereby form a smooth structure as a second layer of the plastic part, wherein the complex structure provides strength to the smooth structure;
- and
- ejecting the plastic part.
Dependencies are inferred from the claim text.