Patent · US Expired

Thermoforming machine with controlled cooling station

US5620715A · kind A · utility

47Cited by
19References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 10, 1994
Grant dateApr 15, 1997
Priority date
Expiry dateFeb 10, 2014

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C51/22
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A four-station rotary thermoformer has a rotary carriage which transports a sheet of thermoplastic material clamped on a subframe through a load/unload station; a heating station; a forming station where the sheet is molded; and a cooling station removed from the mold where the part is cooled on the subframe. The molded sheet is cooled in a cavity which has a lower portion mounted on a lift which travels vertically to engage against an upper portion and enclose the sheet for cooling. A multiplicity of air vents discharge cooling air into the cavity. Cooling air leaves the cavity through recirculation duct. The supply of air within the cooling cavity results in a uniform current of air against the article's surface, thus providing uniform cooling. A programmable controller controls the supply of cooling air and receives input from an infrared sensor which detects the temperature of the thermoformed article and also receives information from a sensor of the cooling air temperature. The programmable controller is programmed to provide a cooling cycle consisting of a three-parts. In the first part, the air is recirculated using the heat capacity of the recirculating air in the air supp…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.