EP0127101B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Inverter for feeding discharge lamps
Assignee: Siemens AG
•
Filing: 1984-05-21
•
Granted: 1987-03-04
•
Expires: 2004-05-21
Abstract
Abstract 1. An inverter comprising two switches (T1, T2) which can be alternately rendered conductive, and comprising a load circuit arranged parallel to the first switch (T1) and connected via the second switch (T2) to a d. c. voltage source (Q), and consisting of the series arrangement of a reversible oscillatory capacitor (C10), a series resonant circuit composed of a choke (L1) and a capacitor (C9), and a discharge lamp (LP) equipped with heatable electrodes, where these electrodes are arranged in the load circuit and are connected to one another via the capacitor (C9) of the series resonant circuit, and comprising a control set (S) which supplies control voltages which alternately render the switches conductive, characterised by a burning voltage sensor (B) which monitors the burning voltage of the lamp (LP) and supplies an output signal dependent upon the burning voltage and fed to the control set (S) to determine the frequency of the control voltages which it supplies.
Inventors
- 👤 Peter Ing. Grad. Krummel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 01:11
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/295; H05B41/298; H05B41/2981; H05B41/2985
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
157 words
An inverter comprising two switches (T1, T2) which can be alternately rendered conductive, and comprising a load circuit arranged parallel to the first switch (T1) and connected via the second switch (T2) to a d. c. voltage source (Q), and consisting of the series arrangement of a reversible oscillatory capacitor (C10), a series resonant circuit composed of a choke (L1) and a capacitor (C9), and a discharge lamp (LP) equipped with heatable electrodes, where these electrodes are arranged in the load circuit and are connected to one another via the capacitor (C9) of the series resonant circuit, and comprising a control set (S) which supplies control voltages which alternately render the switches conductive, characterised by a burning voltage sensor (B) which monitors the burning voltage of the lamp (LP) and supplies an output signal dependent upon the burning voltage and fed to the control set (S) to determine the frequency of the control voltages which it supplies.
Claim 2
Dependent Claim
157 words
An inverter comprising two switches (T1, T2) which can be alternately rendered conductive, and comprising a load circuit arranged parallel to the first switch (T1) and connected via the second switch (T2) to a d. c. voltage source (Q), and consisting of the series arrangement of a reversible oscillatory capacitor (C10), a series resonant circuit composed of a choke (L1) and a capacitor (C9), and a discharge lamp (LP) equipped with heatable electrodes, where these electrodes are arranged in the load circuit and are connected to one another via the capacitor (C9) of the series resonant circuit, and comprising a control set (S) which supplies control voltages which alternately render the switches conductive, characterised by a burning voltage sensor (B) which monitors the burning voltage of the lamp (LP) and supplies an output signal dependent upon the burning voltage and fed to the control set (S) to determine the frequency of the control voltages which it supplies.
Claim 3
Dependent Claim
100 words
An inverter as claimed in Claim 1, characterised by an analyser (A) arranged between the control set (S) and the burning voltage sensor (B) and additionally supplied with the voltage of a timer (Z) connected to the input (PN) of the inverter to determine the frequency of the control voltages during a preliminary heating period (t D /t l ) which commences when the d. c. voltage source is switched on and during a following ignition time (t 1 /t 2 ), and which subsequently actuates the output signal of the burning voltage sensor (B) for the control set (S).
Claim 4
Dependent Claim
93 words
An inverter as claimed in Claim 2, characterised in that the analyser (A) compares a saw-tooth voltage (V C3 ) with a reference voltage (V c4 ) and controls a blocking transistor (T3, T4) in dependence thereon to terminate the control voltage of one of the switches (T2) of the inverter, where the saw-tooth voltage is tapped from a synchronising capacitor (C3) connected via a series resistor (R2) to the d. c. voltage source (Q) and connected in parallel with the switch (T2) which is to be blocked via a series capacitor (C2).
Claim 5
Dependent Claim
61 words
An inverter as claimed in Claim 3, characterised in that the reference voltage (V c4 ) is tapped from a comparator capacitor (C4) arranged in parallel with a control transistor (T5) whose control path is connected via a Zener diode (D8) to a voltage source (R8, R9, C8) which supplies a voltage proportional to the voltage connected to the lamp (LP).
Claim 6
Dependent Claim
46 words
An inverter as claimed in Claim 4, characterised in that the control path of the control transistor (T5) is connected to an RC-component (R6, R7, C6) charged via a decoupling diode (D6) which is conductive only between the switching on of the inverter and its start-up.
Claim 7
Dependent Claim
81 words
An inverter as claimed in Claim 5, with a monitoring device which disconnects the inverter when the lamp is permanently unwilling to ignite, characterised in that the monitoring device (0) is likewise connected at its input to the voltage source (C8) which represents an RC-component (R8, R9, C8) whose time constant is such that the voltage connected to the capacitor (C8) does not reach the response threshold of the monitoring device if the lamp ignites within a predetermined length of time.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.