发明名称 |
High intensity discharge lamp starting circuit with automatic disablement of starting pulses |
摘要 |
A hot restart circuit for a high intensity discharge lamp includes a storage capacitor and SCR connected across a tapped portion of a ballast with a breakdown device to start the SCR. A charging circuit for the storage capacitor includes a diode, a pumping capacitor and an RF choke in series from the ballast tap to the AC line, and a further diode interconnecting the capacitors. The pumping capacitor increases the charge on the storage capacitor in a stepwise fashion until breakdown voltage is reached, whereupon starting pulses are applied to the lamp. A positive temperature coefficient (PTC) resistor stops the flow of charging current to the capacitors after a predetermined interval, thereby terminating the reignition pulses and protecting the starting circuit from damage in case the lamp fails to reignite. In an alternative embodiment, a MOSFET gated by an RC timing circuit removes charge from the storage capacitor in order to terminate the reignition pulses after a predetermined interval.
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申请公布号 |
US5594308(A) |
申请公布日期 |
1997.01.14 |
申请号 |
US19950520514 |
申请日期 |
1995.08.29 |
申请人 |
HUBBELL INCORPORATED |
发明人 |
NUCKOLLS, JOE A.;FLORY, IV, ISAAC L. |
分类号 |
H05B41/04;(IPC1-7):H05B41/14 |
主分类号 |
H05B41/04 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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