Heat/process control
US5262618A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 17, 1992 |
| Grant date | Nov 16, 1993 |
| Priority date | — |
| Expiry date | Jan 17, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D23/22
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A heat/process control is disclosed which takes advantage of the characteristics of some plastics in that they absorb medium wavelength infra-red heat waves in a comparatively wide range of temperatures (and therefore wavelengths). The heaters used in this equipment are of quartz-tube construction which can be used through a wide temperature range. Tests have indicated that lamp wattage and machine processing speed were mathmatically related. For plastics of different formulation and/or thickness a series of parametric curves exist. Each curve is resident in the machine control and can be incorporated with a simple selector switch. For a given plastic a mathmatical equation relating speed and heater temperature is selected. If an increase in speed is required, the target speed and associated temperature is calculated and then loaded into the controller. Since the heaters cannon respond instantaneously, the heaters are fitted with temperature feedback devices which are used to vary the machine speed in accord with the heater actual temperatures. As the heater temperatures rise, the actual temperature of the heaters is input into an equation which calculates an appropriate increase i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.