Automated thermoset molding method

An in-line process for making a fiber reinforced automobile body part, said process comprising the steps of:

• cutting reinforcing fibers with choppers so that the reinforcing fibers fall from the chopper onto a sheet of resin, with the fibers being positioned in parallel horizontal planes on the resin sheet, wherein the reinforcing fibers are greater than 0-5 inch in initial length;
• moving the resin sheet to a cutting unit having a cutting blade for cutting the resin sheet into a plurality of slabs;
• stacking the slabs together to form a multilayered charge;
• transferring the multilayered charge to a charge shuttle unit having at least one transfer shuttle, wherein the transfer shuttle includes a preheater, a shuttle ram, and a closed transfer tube;
• transporting the multilayered charge to a molding unit having a heated upper die, a heated lower die, a transfer pot formed in a lower fixed horizontal member, and a platform driven by a platform driver, wherein the multilayered charge is placed on the platform;
• moving the platform relative to the mold cavity to introduce the charge into the mold cavity so that the reinforcing fibers therein are roughly parallel to the major surface of at least the lower die;
• continuing to move the platform until it is substantially flush with the lower die surface, thereby forcing the charge to flow and fill the mold cavity while maintaining the fibers in an orientation roughly parallel to the die surface to form a fiber reinforced part in which the fiber integrity is essentially undisturbed from initial charge forming through final curing;
• and
• removing the part from the molding cavity of the molding unit.

An in-line process for making a fiber reinforced automobile body part, said process comprising the steps of:

• providing a sheet forming unit having choppers that cut reinforcing fibers and a doctoring blade to control the thickness of a thermosetting resin paste as the fibers fall from the choppers to a sheet of thermosetting resin to form a fiber reinforced resin sheet, wherein the reinforcing fibers are greater than 0.5 inch in initial length;
• passing the sheet into a cutting unit having a cutting blade supported by a frame, wherein the cutting blade cuts the sheet into a plurality of slabs of resin having randomly interspersed reinforcing fibers that are parallel to a horizontal plane, and further wherein the cutting unit is controlled by a programmable computer to produce slabs of selected, preprogrammed sizes;
• delivering the slabs by a conveyor to a layering unit having an automated device containing a pivotally mounted bracket on a supporting structure for stacking the slabs to form a multilayered charge;
• transferring the multilayered charge by the automated device to a charge shuttle unit having at least one transfer shuttle, wherein the transfer shuttle includes a preheater for heating the charge, a shuttle ram, and a closed transfer tube for moving the charge to a molding unit, further wherein the molding unit includes an upper fixed horizontal member, a lower fixed horizontal member, a moveable horizontal member, a heated upper die, a heated lower die, a transfer pot formed in the lower fixed horizontal member, and a platform driven by a platform driver;
• preheating the charge within the preheater prior to loading it onto the platform in the molding unit while simultaneously moving the upper die toward the lower die to define a cavity therebetween;
• transporting the charge by the shuttle ram through the closed transfer tube and a horizontal passageway of the lower fixed horizontal member to the platform where a vacuum pump creates a temporary vacuum in the cavity;
• moving the platform vertically to force the charge into the cavity, wherein the heated upper and lower dies are closed prior to the platform introducing the charge into the cavity, further wherein the reinforcing fibers are distributed throughout the cavity, remain parallel to the horizontal plane, in which the fiber integrity is essentially undisturbed from initial charge forming through final curing to form a fiber reinforced part;
• retracting the upper die;
• and
• removing the fiber reinforced part from the mold cavity.