Patent · US Expired

Humidification system

US4668854A · kind A · utility

27Cited by
15References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 13, 1985
Grant dateMay 26, 1987
Priority date
Expiry dateAug 13, 2005

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF22B1/287
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

The humidity within a chamber is controlled by injecting pulses of steam therein, the duty cycle of the steam pulse input being increased when the humidity of the chamber is lower than desired and decreased when the humidity of the chamber is higher than desired. Each steam pulse is generated by injecting a pulse of water through a small inlet tube into a steam generator comprising a tank surrounded by a band heater, the tank being preheated to a high temperature such that the water quickly turns to steam as it is injected. The steam is then vented into the aforementioned chamber. A detector, mounted within the chamber, produces a signal of magnitude proportional to the relative humidity in the chamber and this signal is input to a control circuit for producing a pulse width modulated control signal of duty cycle varying with the difference between the magnitude of the humidity sensor signal and an adjustable set point signal. The control signal opens and closes a solenoid valve which effects the injection of water into the steam generator.

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