Patent · US Expired

Process for controlling a heater, in particular a defrost heater for refrigerating plants

US4932217A · kind A · utility

13Cited by
4References
3Claims
0Family size

Inventor

Key dates

Filing dateFeb 10, 1989
Grant dateJun 12, 1990
Priority date
Expiry dateFeb 10, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05D23/20
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

In the case of a process for controlling a heater, in particular a defrost heater for a refrigerating plant which has a temperature sensor, which is connected to a system for cutting in and cutting out the heater, during the operation of the heater, the temperature of the room to be heated is measured at certain intervals of time, a measured temperature value being stored in each case and compared with the following measured value, whereupon the heater is cut out whenever the following measured value indicates a temperature which is higher by a certain amount than the preceding stored measured value, and the heater is cut in or remains cut in whenever the following measured value indicates a temperature which is lower by a certain amount than the preceding stored measured value.

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