Apparatus and method for heated pulp press with integral elements for improved efficiencies
A pulp molding machine and split heater plate assembly are contemplated for the manufacture of molded pulp products. The heater plate assembly is split into upper and lower planar members, with grooves formed at the interfacing area of these members and individual cartridge heaters disposed in these grooves. Use of this split heater plate reduces the difference in set temperature of the heater and the observed surface temperature of tooling affixed to the top of the split heater plate, while also delivering up to 15% improvements in the speed of the manufacturing operations relying on that split heater plate.
1 . A split heater plate assembly configured to operate in conjunction with a pulp molding machine, the split heater plate assembly comprising:
a flat planar base member, the flat planar base member having a plurality of grooves disposed in a top facing of the flat planar base member;
at least one elongated, cylindrical cartridge heating element seated in at least one of the grooves in the plurality of grooves; and
a flat planar top member, the flat planar top member having a bottom facing adapted to interface with the top facing of the flat planar base member and the at least one elongated, cylindrical cartridge heating element, a top side opposite the bottom facing, and a peripheral shape complimentary to the base member, wherein:
the flat planar top member includes a plurality of tooling receptacles integrally disposed on the top side, wherein each of the tooling receptacles in the plurality of tooling receptacles is aligned so as to be positioned directly opposite at least one of the at least one elongated, cylindrical cartridge heating element, and
interchangeable tooling is detachably fixed to at least one tooling receptacle in the plurality of tooling receptacles;
wherein:
the at least one elongated, cylindrical cartridge heating element is electrically heated;
the at least one elongated, cylindrical cartridge heating element is in direct thermal communication with the interchangeable tooling via conductive heat transfer from the at least one elongated, cylindrical cartridge heating element through the flat planar top member to the interchangeable tooling; and
the interchangeable tooling is free of any heating element disposed therein.
2 . The assembly of claim 1 wherein every one of the grooves in the plurality of grooves receives a corresponding elongated, cylindrical cartridge heating element.
3 . The assembly of claim 1 wherein the plurality of tooling receptacles includes fluid flow channels at least partially embedded in the top side of the flat planar top member.
4 . The assembly of claim 1 wherein the plurality of tooling receptacles includes molding tool fasteners.
5 . The assembly of claim 1 wherein the bottom facing of the flat planar top member includes a plurality of corresponding grooves, with each corresponding groove in the plurality of corresponding grooves being configured to align with and receive an exposed facing of one of the at least one elongated, cylindrical cartridge heating element.
6 . The assembly of claim 1 wherein the grooves in the plurality of grooves extend from one edge to an opposing edge of the flat planar base member.
7 . The assembly of claim 1 wherein the grooves in the plurality of grooves are regularly spaced apart.
8 . The assembly of claim 1 wherein all of the grooves in the plurality of grooves are parallel.
9 . The assembly of claim 1 wherein a retainer channel is formed in the top facing of the flat planar base member, said retainer channel aligned perpendicular to and intersecting with each one of the grooves in the plurality of grooves, and a plurality of retainers secured in the retainer channel to maintain the positioning of every elongated, cylindrical cartridge heating element of the at least one elongated, cylindrical cartridge heating element provided in the plurality of grooves.
10 . A pulp molding machine for manufacturing molded pulp products comprising:
the split heater plate assembly according to claim 1 ;
a tooling press assembly having complimentary interchangeable tooling detachably fixed to a lower facing;
wherein the split heater plate assembly and the tooling press assembly are configured to move into close proximity during a molding operation so that the interchangeable tooling on the split heater plate assembly and the complimentary interchangeable tooling on the tooling press assembly collectively define a pulp product mold; and
wherein the at least one elongated, cylindrical cartridge heating element is configured to be in thermal communication with the top member of the split heater plate assembly so that, after attaining steady state operation, an observed temperature on an outermost surface of the interchangeable tooling on the split heater plate assembly is at least 78% or greater than a set temperature of the at least one elongated, cylindrical cartridge heaters heating element.
11 . The machine of claim 10 configured to provide an observed temperature of the flat planar top member of the split heater plate assembly within 98% of an observed temperature of the flat planar base member of the split heater plate assembly at all times during the molding operation.
12 . A pulp molding machine for manufacturing molded pulp products comprising:
a split heater plate assembly having: i) a lower plate member with a series of spaced apart channels each running transversely across a top facing of the lower plate member, and ii) an upper plate member configured to couple to the top facing of the lower plate member so as to cover and enclose the spaced apart channels, wherein interchangeable tooling is detachably fixed to a top side of the upper plate member directly opposite each one of the spaced apart channels;
a plurality of elongated, cylindrical cartridge heating elements with an individual elongated, cylindrical cartridge heating element seated in each of the spaced apart channels;
a tooling press assembly having complimentary interchangeable tooling detachably fixed to a lower facing;
wherein the split heater plate assembly and the tooling press assembly are configured to move into close proximity during a molding operation;
wherein the interchangeable tooling is free of any heating element disposed therein; and
wherein the plurality of elongated, cylindrical cartridge heating elements are configured to be in thermal communication with the interchangeable tooling through the upper plate member so that, after attaining steady state operation, an observed temperature on an outermost surface of the interchangeable tooling of the split heater plate assembly is at least 78% or greater than a set temperature of the plurality of elongated, cylindrical cartridge heating elements.
13 . The machine of claim 12 configured to provide an observed temperature of the upper plate member of the split heater plate assembly within 98% of an observed temperature of the lower plate member of the split heater plate assembly at all times during the molding operation.