Projection lamp safety interlock apparatus and method
US6424097B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 2000 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | May 12, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/2925
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A safety interlock apparatus for an electrical device includes a DC power supply, a ballast power supply including a ballast control circuit that controls a ballast power circuit, and a lamp. A relatively low voltage electrical connection is present between the DC power supply and the ballast control circuit. A relatively high voltage electrical connection is present between the lamp and the ballast power circuit. A safety interlock switch is positioned on the relatively low voltage electrical connection, the switch having a closed state wherein the relatively low voltage is supplied to the ballast control circuit and an open disconnected state wherein the relatively low voltage electrical connection is disconnected. A panel is fixable to the electrical device frame, and is selectively movable to expose the lamp for removal. The panel has a switch actuator positioned thereon operable to actuate the interlock switch to the open disconnected state when the panel is removed from the device, thereby disconnecting power to the ballast control circuit, which in turn immediately disables the ballast power circuit, rendering the lamp safe for removal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.