Automatic air defrost system
US10476416B2 · kind B2 · utility
0Cited by
3References
30Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2016 |
| Grant date | Nov 12, 2019 |
| Priority date | — |
| Expiry date | Aug 10, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P29/40
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for controlling the direction of a defrost device for refrigeration coils includes measuring the current drawn by or the torque produced by a permanent magnet motor, wherein the permanent magnet motor powers a defrost device recurrently back and forth along refrigeration coils and reverses the direction of the permanent magnet motor when the measured current drawn or measured torque produced are at or above a first limit. The method omits the use of switches and sensors to signal when the defrost device is reversed to reduce failures and stoppages.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.