US5365152A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for controlling the power to a discharge-lamp
Assignee: Panasonic Holdings Corp
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Filing: 1992-08-18
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Granted: 1994-11-15
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Expires: 2012-08-18
Abstract
Abstract In a discharge-lamp lighting apparatus for lighting a discharge lamp such as a metal halide lamp, there is provided a lighting control circuit which controls its output in a starting time of the discharge lamp in response to at least a length of the last off-time and an on-time after the start of discharging; and a power supplied to the discharge lamp is controlled in accordance with this output of the lighting control circuit.
Inventors
- 👤 Masataka Ozawa
- 👤 Takayuki Kamitani
- 👤 Kazutaka Koyama
- 👤 Shigeru Horii
- 👤 Koji Miyazaki
- 👤 Nobuhisa Yoshikawa
- 👤 Takeshi Saito
- 👤 Kazuhiko Ito
- 👤 Masayoshi Gyoten
- 👤 Atsuo Waki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:27
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/288; H05B41/2881; H05B41/2882; H05B41/36; H05B41/38; H05B41/382; H05B41/386
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
141 words
A discharge-lamp lighting apparatus comprising; a discharge lamp; lamp current supply means for supplying said discharge lamp with a current; and lighting control means for controlling an output of said lamp current supply means in response to an off-time and an on-time of said discharge lamp, said lighting control means increasing its initial output in response to increase of said off-time and decreasing its output to a rated output as time lapses after start-up of said discharge lamp; said lighting control means determines an output level of said lamp current supply means, which is in a state just after start-up of said discharge lamp, within a time period from power-on of said lamp current supply means to start-up of said discharge lamp; and said lighting control means decreases said output level to a rated level as time lapses after said start-up.
Claim 2
Dependent Claim
141 words
A discharge-lamp lighting apparatus comprising; a discharge lamp; lamp current supply means for supplying said discharge lamp with a current; and lighting control means for controlling an output of said lamp current supply means in response to an off-time and an on-time of said discharge lamp, said lighting control means increasing its initial output in response to increase of said off-time and decreasing its output to a rated output as time lapses after start-up of said discharge lamp; said lighting control means determines an output level of said lamp current supply means, which is in a state just after start-up of said discharge lamp, within a time period from power-on of said lamp current supply means to start-up of said discharge lamp; and said lighting control means decreases said output level to a rated level as time lapses after said start-up.
Claim 3
Dependent Claim
246 words
A discharge-lamp lighting apparatus comprising: a discharge lamp; lamp current supply means for supplying said discharge lamp with a current; lamp voltage detection means for detecting a lamp voltage applied to said discharge lamp; lamp current detection means for detecting a lamp current flowing in said discharge lamp; power control means which receives outputs of said lamp voltage detection means and said lamp current detection means to control a lamp power of said discharge lamp; and a lighting control circuit which receives an output of said lamp voltage detection means within a starting-time of said discharge lamp and issues an output signal for controlling said lamp power to said power control means, said lighting control circuit changing a level of said output signal in inverse relation to said lamp voltage and issuing a constant output signal for lighting said discharge lamp with a rated power after said starting time; said lighting control circuit comprises: i.) lamp power arithmetic means, which decrease its output signal in a lamp voltage range less than a predetermined voltage in response to increase of said lamp voltage and renders said output signal zero in a lamp voltage range equal to or more than said predetermined voltage; and ii.) bias means for biasing said lighting control circuit with a predetermined voltage output; and an output of said lamp current supply means is controlled by an output based on a sum of outputs of said lamp power arithmetic means and said bias means.
Claim 4
Dependent Claim
246 words
A discharge-lamp lighting apparatus comprising: a discharge lamp; lamp current supply means for supplying said discharge lamp with a current; lamp voltage detection means for detecting a lamp voltage applied to said discharge lamp; lamp current detection means for detecting a lamp current flowing in said discharge lamp; power control means which receives outputs of said lamp voltage detection means and said lamp current detection means to control a lamp power of said discharge lamp; and a lighting control circuit which receives an output of said lamp voltage detection means within a starting-time of said discharge lamp and issues an output signal for controlling said lamp power to said power control means, said lighting control circuit changing a level of said output signal in inverse relation to said lamp voltage and issuing a constant output signal for lighting said discharge lamp with a rated power after said starting time; said lighting control circuit comprises: i.) lamp power arithmetic means, which decrease its output signal in a lamp voltage range less than a predetermined voltage in response to increase of said lamp voltage and renders said output signal zero in a lamp voltage range equal to or more than said predetermined voltage; and ii.) bias means for biasing said lighting control circuit with a predetermined voltage output; and an output of said lamp current supply means is controlled by an output based on a sum of outputs of said lamp power arithmetic means and said bias means.
Claim 5
Dependent Claim
56 words
A discharge-lamp lighting apparatus in accordance with claims 2, wherein said lighting control circuit comprises a time-constant changeover circuit which is connected to said lamp power arithmetic means to be operated by a predetermined lamp voltage; and said time-constant changeover circuit increases a time constant of lowering a lamp power in said lamp power arithmetic means.
Claim 6
Dependent Claim
229 words
A discharge-lamp lighting apparatus comprising: a discharge lamp; lamp current supply means for supplying said discharge lamp with a current; lamp voltage detecting means for detecting a lamp voltage applied to said discharge lamp; lamp current detection means for detecting a lamp current flowing in said discharge lamp; power control means which receives outputs of said lamp voltage detection means and said lamp current detection means to control a lamp power of said discharge lamp; and a lighting control circuit which receives an output of said lamp voltage detection means within a starting-time of said discharge lamp and issues an output signal for controlling said lamp power to said power control means, said lighting control circuit changing a level of said output signal in inverse relation to said lamp voltage and issuing a constant output signal for lighting said discharge lamp with a rated power after said starting time; said lighting control circuit comprises starting power setting means for setting a predetermined initial lamp power, which is larger than a lamp power of a steady lighting state, just after start of discharging; and said lighting control circuit issues an output signal based on a larger one of said initial lamp power and a power determined by said lamp voltage and after start-up issues an output signal for lighting said discharge lamp with a rated power after said starting time.
Claim 7
Dependent Claim
229 words
A discharge-lamp lighting apparatus comprising: a discharge lamp; lamp current supply means for supplying said discharge lamp with a current; lamp voltage detecting means for detecting a lamp voltage applied to said discharge lamp; lamp current detection means for detecting a lamp current flowing in said discharge lamp; power control means which receives outputs of said lamp voltage detection means and said lamp current detection means to control a lamp power of said discharge lamp; and a lighting control circuit which receives an output of said lamp voltage detection means within a starting-time of said discharge lamp and issues an output signal for controlling said lamp power to said power control means, said lighting control circuit changing a level of said output signal in inverse relation to said lamp voltage and issuing a constant output signal for lighting said discharge lamp with a rated power after said starting time; said lighting control circuit comprises starting power setting means for setting a predetermined initial lamp power, which is larger than a lamp power of a steady lighting state, just after start of discharging; and said lighting control circuit issues an output signal based on a larger one of said initial lamp power and a power determined by said lamp voltage and after start-up issues an output signal for lighting said discharge lamp with a rated power after said starting time.
Claim 8
Dependent Claim
77 words
A discharge-lamp lighting apparatus in accordance with claim 4, wherein said starting power setting means comprises an off-time processing circuit for detecting a length of an off-time of said discharge lamp and a starting power setting trigger circuit for making said off-time processing circuit issue an output signal by which said initial lamp power is determined in response to a length of said off-time; and said initial lamp power is based on a length of said off-time.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-14 | 1998-05-16 | 1998-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-14 | 2002-05-16 | 2002-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-14 | 2006-05-16 | 2006-11-15 | $7700.00 | Window Closed / Lapsed |