Vehicle headlamp apparatus
US6918688B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 31, 2003 |
| Grant date | Jul 19, 2005 |
| Priority date | — |
| Expiry date | Jan 5, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60Q2200/38
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A vehicle headlamp device contains a rotation-state recognizing circuit operating such that when any of Hall elements used for controlling a rotational position of a drive motor for deflecting the optical axes in a headlamp device is abnormal, a rotation-state recognizing circuit recognizes a rotational position of the drive motor based on the output signals of the remaining Hall elements and a predetermined angle prediction time computed using a rotational period of the drive motor. With provision of the rotation-state recognizing circuit, even when any of the Hall elements becomes defective, the rotation of the drive motor is normally controlled to thereby secure a proper optical-axis deflection control in the headlamp device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.