Motor vehicle cooling apparatus with electric motor surge current inhibitor
US6125798A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 1998 |
| Grant date | Oct 3, 2000 |
| Priority date | — |
| Expiry date | Nov 25, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01P7/08
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A cooling apparatus for automotive use wherein speed of an electric cooling fan is controlled solely at a predetermined speed. When a relay switch is switched on, voltage of a battery is applied to a lag circuit. Output of the lag circuit is applied to a gate G of a MOS transistor, but rise of the gate-applied voltage is delayed by the lag circuit according to a time constant thereof, and increases slowly. When the gate-applied voltage reaches the threshold voltage of the MOS transistor, the MOS transistor begins to switch on. However, when the gate-applied voltage is low, the drain current flowing through the MOS transistor is limited and thereby surge current at the motor is minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.