Electric fluid heater temperature control system providing precise control under varying conditions
US4501952A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 1982 |
| Grant date | Feb 26, 1985 |
| Priority date | — |
| Expiry date | Jun 7, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D23/24
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A fluid heater, particularly for heating paints, lacquers, varnishes and other spray coating material, includes an elongated hollow tube adapted to be inserted into a fluid flow line for fluid flow through the tube. An electric resistance heater is disposed within the tube and is surrounded by a helical coil member to create a helical fluid flow path through the tube. A temperature control system for regulating the operation of the heater is provided and includes a temperature sensing probe comprising a temperature responsive resistance element enclosed in a conical housing extending into the helical fluid flow path and having its apex contacting the heater and its conical surface area increasing in a direction away from the heater and extending across the cross section of the fluid flow path. The temperature control system is responsive to both the temperature and the rate of change of temperature of the probe and includes an ambient temperature compensation circuit for monitoring the ambient temperature and compensating temperature control circuits for regulating heater temperature as a function of ambient temperature as well as a function of static and dynamic fluid flow conditi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.