METHOD AND APPARATUS FOR MAKING A PART

1 . A method of making a part, the method comprising:

introducing expandable material into a cavity of a mold containing a substrate, the mold including at least one projection extending into the cavity; and

retracting the at least one projection to allow the expandable material to expand in the cavity, such that the expandable material forms an expanded material layer on the substrate.

2 . The method of claim 1 wherein each projection extends through an aperture in the substrate prior to the retracting step.

3 . The method of claim 1 further comprising pressurizing the cavity, wherein the pressurizing step commences prior to the introducing step.

4 . The method of claim 3 further comprising reducing pressure in the cavity prior to the retracting step.

5 . The method of claim 1 wherein the at least one projection includes multiple projections that are configured to extend through multiple apertures in the substrate and into the cavity prior to the retracting step, and wherein the retracting step includes retracting the projections to allow the expandable material to expand in the cavity.

6 . The method of claim 5 further comprising pressuring the cavity prior to the introducing step, and reducing pressure in the cavity prior to the retracting step.

7 . The method of claim 1 wherein the expanded material layer is a resilient layer.

8 . The method of claim 7 wherein the expanded material layer comprises foam.

9 . The method of claim 1 further comprising forming the substrate using at least a portion of the mold such that the substrate includes multiple apertures, wherein the at least one projection includes multiple projections that extend through the apertures of the substrate and into the cavity prior to the retracting step, and wherein the retracting step includes retracting the projections to allow the expandable material to expand in the cavity.

10 . The method of claim 1 wherein the introducing step comprises introducing a blowing agent into the cavity.

11 . A method of making a part, the method comprising:

pressurizing a cavity of a mold having a substrate positioned therein, the mold including multiple projections that extend through multiple apertures of the substrate and into the cavity;

introducing expandable plastic material into the cavity;

reducing pressure in the cavity after the introducing step; and

retracting the projections to allow the plastic material to expand in the cavity, such that the plastic material forms a resilient foam layer on the substrate, the resilient layer providing an appearance surface of the part.

12 . An apparatus for making a part, the apparatus comprising:

a mold having a cavity configured to receive a substrate having an aperture, the mold including a moveable projection that is configured to extend through the aperture of the substrate and into the cavity; and

an expandable material introduction device for introducing expandable material into the cavity;

wherein the mold is configured to retract the projection after the expandable material has been introduced into the cavity, to thereby provide space for expansion of the expandable material.

13 . The apparatus of claim 12 wherein the mold includes multiple moveable projections that are configured to extend through multiple apertures of the substrate and into the cavity, and wherein the mold is configured to retract the projections after the expandable material has been introduced into the cavity.

14 . The apparatus of claim 12 further comprising a pressure source for pressurizing the cavity.