US 5,458,477 A · Apparatus for continous three-dimensional forming of heated thermoplastic materials

Abstract

Continuous impression forming of three-dimensional products from heated, formable thermoplastic materials between top and bottom mold carriages each having a three-dimensional forming belt mold revolvable around the carriage. Each three-dimensional forming belt mold includes a flexible silicone rubber mold adhered to a multi-ply woven fabric belt. A surface of desired shape on one revolving rubber mold mates with the desired shape of an opposed revolving rubber mold forming a continuously moving mold channel between the mold belts into which is fed hot thermoplastic material at moldable temperature. After discharging molded plastic product from the exit of the moving mold channel, localized surface heat in the rubber molds resulting from contact with hot plastic is removed by air blown directly onto the rubber mold surfaces. Each carriage frame includes a back-up plate coated with low friction coefficient material over which slides a continuously moving belt mold. These slippery plates have numerous air-bearing holes feeding air between them and the respective moving woven fabric belt for reducing friction and wear. The woven fabric belts are guided and they are driven by an electric drive motor, with or without torque-motor assistance, for revolving both belt molds in unison maintaining their mating alignment. Electric screw jacks raise the top carriage, extend/retract grooved exit rolls, fine-tune alignment of revolving belt molds by adjusting grooved exit rolls and adjust the machine relative to the in-feed of heated thermoplastic materials.

Claims20

Dependent claims

A pair of endless flexible belt molds for use in a machine for revolving said belt molds in opposed relationship for continuous three-dimensional impression-forming between said belt molds of products having three-dimensionally configured surface patterns produced from heated, formable thermoplastic material, said pair of belt molds comprising:

first and second endless flexible backing belts;
each of said backing belts including a plurality of plies of woven fibers;
said plies of woven fibers in each backing belt being bonded together in laminated relationship;
said first endless flexile backing belt having a first endless flexible mold form adhered to an exterior surface thereof;
said first mold form having a first exterior three-dimensional impression-forming surface;
said second endless flexible backing belt having a second endless flexible mold form adhered to an exterior surface thereof;
said second mold form having a second exterior three-dimensional impression-forming surface;
said first and second mold forms being disposable in laminar juxtaposition with said first and second impression-forming surfaces facing toward each other defining at least one three-dimensional forming channel between said impression-forming surfaces for three-dimensional impression-forming in said channel of products having three-dimensionally configured surface patterns produced from heated, formable thermoplastic material.

5 more elements

A pair of endless flexible belt molds for use in a machine for continuous three-dimensional impression forming of products from heated, formable thermoplastic material between the first and second belt molds in use as they revolve around respective first and second carriages in such machine having drive means for revolving the first and second belt molds around such respective carriages, said pair of belt molds comprising:

a first endless, flexible backing belt having a plurality of plies of fabric;
said plurality of plies of fabric in said first backing belt being bonded together in laminated relationship;
a first endless flexible rubber mold form adhered to said first backing belt with said backing belt being on an inner side of said first belt mold and with said rubber mold form being on an outer side of said first belt mold;
said first rubber mold form having a first three-dimensional impression-forming surface on its outer side;
a second endless, flexible backing belt having a plurality of plies of fabric;
said plurality of plies of fabric in said second backing belt being bonded together in laminated relationship;
a second endless flexible rubber mold form adhered to said second backing belt with said second backing belt being on an inner side of said second belt mold and with said second rubber mold form being on an outer side of said second belt mold;
said second rubber mold form having a second three-dimensional impression-forming surface on its outer side;
and
said first and second belt molds being positionable in opposed relationship with portions of said first and second rubber mold forms being in contact with each other for defining at least one channel between said first and second impression-forming surfaces useful for forming in said channel products having three-dimensionally configured surface patterns produced from heated, formable thermoplastic material.

7 more elements

A pair of endless flexible belt molds for use in a machine for revolving said belt molds in opposed relationship for continuous three-dimensional forming between the first and second belt molds of products having three-dimensionally configured surface patterns produced from moldable plastic material, said first and second endless flexible belt molds comprising:

first and second endless flexible backing belts;
said first backing belt being a multi-ply laminated fiber belt having a first inner surface and a first outer surface;
said second backing belt being a multi-ply laminated fiber belt having a second inner surface and a second outer surface;
a first flexible mold extending along said first outer surface and being bonded to said first outer surface;
said first flexible mold having a first three-dimensional forming surface facing outwardly;
a second flexible mold extending along said second outer surface and being bonded to said second outer surface;
said second flexible mold having a second three-dimensional forming surface facing outwardly;
and
said first and second endless flexible molds being revolvable with said first and second three-dimensional forming surfaces positionable in opposed relationship for defining at least one moving three-dimensional forming channel therebetween for continuous three-dimensional forming in said channel of products having three-dimensionally configured surface patterns produced from moldable plastic material.

6 more elements

Dependencies are inferred from the claim text.

Apparatus for continous three-dimensional forming of heated thermoplastic materials

Life of this patent

Apparatus for continous three-dimensional forming of heated thermoplastic materials

Life of this patent

Abstract

Claims20