US5932976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Discharge lamp driving
Assignee: Panasonic Electric Works Co Ltd
•
Filing: 1997-01-14
•
Granted: 1999-08-03
•
Expires: 2017-01-14
Abstract
Abstract A discharge lamp driving circuit includes DC voltage input connections, lamp driving connections, bridge circuitry, and control circuitry. The bridge circuitry is connected to the DC voltage input connections and to the lamp driving connections and includes circuit elements which in one mode of operation deliver a higher frequency AC voltage to the lamp driving connections and in another mode of operation deliver a lower frequency AC voltage to the lamp driving connections. The control circuitry is connected to control the bridge circuitry selectively as either a half-bridge to deliver the higher frequency AC voltage to the lamp driving connections during starting or a full-bridge to deliver only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting. A low frequency driver and a high frequency driver are connected to drive the bridge circuitry.
Inventors
- 👤 Ajay Maheshwari
- 👤 Tokushi Yamauchi
- 👤 Kiyoaki Uchihashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:44
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/288; H05B41/2881; H05B41/2882; H05B41/2883; H05B41/2885; H05B41/2887; H05B41/2888; H05B41/36; H05B41/38; H05B41/382; H05B41/388; Y; Y02; Y02B; Y02B20/00; Y10; Y10S; Y10S315/00; Y10S315/05; Y10S315/07
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
117 words
A discharge lamp driving circuit comprising DC voltage input connections, lamp driving connections, bridge circuitry connected to the DC voltage input connections and to the lamp driving connections and including circuit elements which in one mode of operation deliver a higher frequency AC voltage to the lamp driving connections and in another mode of operation deliver a lower frequency AC voltage to the lamp driving connections, and control circuitry connected to control the bridge circuitry selectively as either a half-bridge to deliver the higher frequency AC voltage to the lamp driving connections during starting or a full-bridge to deliver only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting.
Claim 2
Dependent Claim
117 words
A discharge lamp driving circuit comprising DC voltage input connections, lamp driving connections, bridge circuitry connected to the DC voltage input connections and to the lamp driving connections and including circuit elements which in one mode of operation deliver a higher frequency AC voltage to the lamp driving connections and in another mode of operation deliver a lower frequency AC voltage to the lamp driving connections, and control circuitry connected to control the bridge circuitry selectively as either a half-bridge to deliver the higher frequency AC voltage to the lamp driving connections during starting or a full-bridge to deliver only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting.
Claim 3
Dependent Claim
124 words
A discharge lamp driving circuit comprising DC voltage input connections, lamp driving connections, bridge circuitry connected to the DC voltage input connections and to the lamp driving connections, and including a low frequency driver and a high frequency driver connected to drive the bridge circuitry so that in one mode of operation a higher frequency AC voltage is delivered to the lamp driving connections and in another mode of operation a lower frequency AC voltage is delivered to the lamp driving connections, and control circuitry connected to control the bridge circuitry to deliver the higher frequency AC voltage to the lamp driving connections during starting or only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting.
Claim 4
Dependent Claim
124 words
A discharge lamp driving circuit comprising DC voltage input connections, lamp driving connections, bridge circuitry connected to the DC voltage input connections and to the lamp driving connections, and including a low frequency driver and a high frequency driver connected to drive the bridge circuitry so that in one mode of operation a higher frequency AC voltage is delivered to the lamp driving connections and in another mode of operation a lower frequency AC voltage is delivered to the lamp driving connections, and control circuitry connected to control the bridge circuitry to deliver the higher frequency AC voltage to the lamp driving connections during starting or only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting.
Claim 5
Dependent Claim
23 words
The driving circuit of claim 1 or 2 in which the bridge circuitry includes four bidirectional conducting portions connected in a bridge configuration.
Claim 6
Dependent Claim
34 words
The driving circuit of claim 1 or 2 in which the bridge circuitry includes a resonant circuit having an inductor and a capacitor, the inductor being connected to one of the lamp driving connections.
Claim 7
Dependent Claim
35 words
The driving circuit of claim 4 in which the control circuitry is connected to sweep the frequency of the AC voltage during starting through a range that includes a resonant frequency of the resonant circuit.
Claim 8
Dependent Claim
21 words
The driving circuit of claim 4 in which the capacitor is also connected to the one of the lamp driving connections.
Claim 9
Dependent Claim
21 words
The driving circuit of claim 4 in which the capacitor is connected to a tap of a winding of the inductor.
Claim 10
Dependent Claim
27 words
The driving circuit of claim 4 in which the control circuitry is connected to drive the bridge circuitry at essentially a resonant frequency of the resonant circuit.
Claim 11
Dependent Claim
41 words
The driving circuit of claim 2 in which the bridge circuit includes four switches, the low frequency driver is connected to drive two of the switches, and the high frequency driver is connected to drive the other two of the switches.
Claim 12
Dependent Claim
26 words
The driving circuit of claim 9 in which the low frequency driver is connected to selectively drive the two switches at DC on or DC off.
Claim 13
Dependent Claim
24 words
The driving circuit of claim 10 in which the control circuitry is connected to drive one of the two switches at DC during starting.
Claim 14
Dependent Claim
24 words
The driving circuit of claim 2 in which the control circuitry is connected to the low frequency driver and to the high frequency driver.
Claim 15
Dependent Claim
58 words
The driving circuit of claim 12 further comprising a resonant circuit connected between the commonly connected ends of the two switches of the one pair and one of the lamp driving connections and in which the commonly connected ends of the two switches of the other pair are connected to the other one of the lamp driving connections.
Claim 16
Dependent Claim
32 words
The driving circuit of claim 1 or 2 in which the control circuitry is connected to control the bridge circuitry to operate in the starting mode only until the lamp is ignited.
Claim 17
Dependent Claim
38 words
The driving circuit of claim 14 in which the control circuitry is connected to control the bridge circuitry during starting to repeatedly and alternately stop operation of the bridge circuit and to continue operation in the starting mode.
Claim 18
Dependent Claim
28 words
The driving circuit of claim 14 in which the control circuit is connected to control the bridge circuitry to deliver essentially DC to the lamp immediately after starting.
Claim 19
Independent Claim
59 words
A method of driving a discharge lamp comprising operating a bridge circuit as a half bridge to deliver a higher frequency AC voltage from bridge circuitry to the lamp during starting, and operating the bridge circuit as a full-bridge to deliver only lower frequency AC operating voltage from the bridge circuitry to the lamp during normal operation after starting.
Claim 20
Independent Claim
59 words
A method of driving a discharge lamp comprising operating a bridge circuit as a half bridge to deliver a higher frequency AC voltage from bridge circuitry to the lamp during starting, and operating the bridge circuit as a full-bridge to deliver only lower frequency AC operating voltage from the bridge circuitry to the lamp during normal operation after starting.
Claim 21
Dependent Claim
28 words
The method of claim 17 further comprising sweeping the frequency of the AC voltage during starting through a range that includes a resonant frequency of a resonant circuit.
Claim 22
Dependent Claim
23 words
The method of claim 17 in which the bridge circuitry is driven at essentially a resonant frequency of the resonant circuit during starting.
Claim 23
Dependent Claim
22 words
The method of claim 17 in which the bridge circuitry is operated in the starting mode only until the lamp is ignited.
Claim 24
Dependent Claim
25 words
The method of claim 17 further comprising, during starting, repeatedly and alternately stopping operation of the bridge circuit and continuing operation in the starting mode.
Claim 25
Dependent Claim
16 words
The method of claim 17 further comprising delivering essentially DC to the lamp immediately after starting.
Claim 26
Dependent Claim
159 words
A discharge lamp driving circuit comprising DC voltage input connections, lamp driving connections, and bridge circuitry connected to the DC voltage input connections and to the lamp driving connections and including circuit elements which in one mode of operation deliver a higher frequency AC voltage to the lamp driving connections and in another mode of operation deliver a lower frequency AC voltage to the lamp driving connections, the bridge circuitry including four unidirectional conducting portions connected in a bridge configuration, a low frequency driver, a high frequency driver connected to drive one-half of the bridge, a resonant circuit having an inductor and a capacitor, the inductor being connected to one of the lamp driving connections, and control circuitry connected to control the bridge circuitry to deliver the higher frequency AC voltage to the lamp driving connections during starting and to deliver only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting.
Claim 27
Dependent Claim
159 words
A discharge lamp driving circuit comprising DC voltage input connections, lamp driving connections, and bridge circuitry connected to the DC voltage input connections and to the lamp driving connections and including circuit elements which in one mode of operation deliver a higher frequency AC voltage to the lamp driving connections and in another mode of operation deliver a lower frequency AC voltage to the lamp driving connections, the bridge circuitry including four unidirectional conducting portions connected in a bridge configuration, a low frequency driver, a high frequency driver connected to drive one-half of the bridge, a resonant circuit having an inductor and a capacitor, the inductor being connected to one of the lamp driving connections, and control circuitry connected to control the bridge circuitry to deliver the higher frequency AC voltage to the lamp driving connections during starting and to deliver only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting.
References Cited (Backward Citations)
US3969652A
Cited
US4734624A
Cited
US4949015A
Cited
US4912374A
Cited
US5517088A
Cited
US5491386A
Cited
JPH08124687A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-08-02 | 2003-02-01 | 2003-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-02 | 2007-02-01 | 2007-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-02 | 2011-02-01 | 2011-08-03 | $7700.00 | Window Closed / Lapsed |