U.S. Philips Corporation

Ralf Schafer

Hans Peter Stormberg

Hans G Ganser

Hans-Peter Stormberg

Manfred Westemeyer

Hans-Gunther Ganser

Armin F Wegener

Hans J Kohl

Manfred Albach

Horst Dannert

Leonardus U Konings

Cornelis Johannes Janson

The capped electric lamp has a quartz glass lamp vessel (1) having first and second neck-shaped portions (2,3) with respective seals (4,5). A glass envelope (9) surrounds the lamp vessel and is secured thereto. A clamping member (20) surrounds the envelope in a clamping manner. A fixation member (32) of a lamp cap (30) is welded to the clamping member. The clamping member (20) is an undulated metal body, the crests of its creases constituting regions (22) which are spaced from the envelope (9) and in which welds to the fixation member (32) are made. Its troughs constitute clamping zones (21) which hold the envelope. The clamping member (20) allows for the application of a relatively wide envelope (9), which may enter the lamp cap (30).

Lamp envelope with a metal clamping member and a fixation member

The capped high pressure discharge lamp includes a light source (1) having a lamp vessel (1') with a first neck shaped portion (2) to which a lamp cap (30) is fixed. A connection conductor (7) runs alongside the discharge vessel to connect a second current supply conductor (5) extending from a second neck shaped portion (3) to a second contact member (36) of the cap. The lamp vessel (1') is contained by a tubular outer envelope (20), which is filled with air and does not envelope the connection conductor (7). The outer envelope (20, 50) has a narrowing portion (21, 52, 51) which encloses the second current supply conductor (5) or a neck shaped portion (2, 3). The outer envelope is maintained. The lamp is of a simple construction which allows for optimizing the light output or the temperature of the lamp vessel.

Capped high-pressure discharge lamp

The capped electric lamp has a glass lamp vessel (1) having first and second neck-shaped portions (2,3). An outer glass envelope (8) has a narrowed portion (9) where it is coupled to the first neck-shaped portion (2). A metal sleeve (10) has a clamping zone (11) which clampingly holds the outer envelope (8), and a welding zone (12) to which tongues (21) of a fixation member (20) which is fixed in a lamp cap (30) are welded. The metal sleeve (10) becomes narrower from the clamping zone (11) towards the first neck-shaped portion (2) up to the welding zone (12).

Capped electric lamp

A circuit arrangement is described for supplying a load (1) from a direct voltage source (14) through a switch bridge (3 to 6), by which the direct voltage source (14) can be connected in alternating polarity to the load (1), comprising a control circuit (17) for controlling the switch bridge (3 to 6); and including a circuit for precisely adjusting and controlling a given D.C. component through the load by a device for measuring a current (I1) through the load (1) and supplying a corresponding measurement value and in that the control circuit (17) comprises an integration stage (18) for integrating the measurement value, a comparison stage (20) for comparing the integrated measurement value with a reference value (of 21) and for supplying a switching signal (at 22) when these values correspond to each other and a signal-producing stage (23) for resetting the integration stage (18) to an initial state and for reversing the polarity of the current (I1) through the load (1) upon the occurrence of the switching signal (at 22).

Circuit arrangement for supplying a load

A circuit arrangement for A.C. operation of high-pressure gas discharge lamps comprising a mains alternating voltage source and a high-frequency oscillator (3) supplied with direct current and which produces a high-frequency current through the lamp superimposed on the mains alternating lamp current. The oscillator comprises a high-frequency transformer (7) and a transistor (11) connected in series with the transformer primary (8). The transistor can be periodically switched on an off. A secondary (9) of the transformer is connected in series with the lamp. Losses are reduced if the ratio between the switching-on and switching-off time (duty cycle) of the transistor (11) is chosen so small that the effective value of the high-frequency current coupled into the lamp lies between 0.05 and 5% of the mains alternating lamp current. An auxiliary device (16 to 19, 25) interrupts the periodic switching of the transistor (11) outside the proximity of the zero passages of the mains alternating lamp current.

Circuit arrangement for A.C. operation of high-pressure gas discharge

A circuit arrangement for starting and operating gas discharge lamps with current of higher frequency comprises an electronic ballast unit connected to a direct voltage input source (2). An electronic switching element (3), which is controlled by a control device (8), is connected in series with an inductive element (4), and the discharge lamp (5). The lamp current flows through the inductive element from which a voltage is derived which is supplied to the control device as a supply direct voltage supply via a rectifier (14) and a smoothing capacitor (16). A first connection terminal of the smoothing capacitor is connected through a first ohmic resistor (18) to a first terminal of the direct voltage input source and a second connection of the capacitor is connected through the lamp (5) to a second terminal of the direct voltage input source.

Circuit arrangement for starting and operating gas discharge lamps

A circuit arrangement for adjusting the operating voltage of high-pressure gas discharge lamps to a given nominal value, comprises a controllable current limiter connected in series with the lamp and an adjustment circuit (3) for controlling the latter. The output signal of the adjustment circuit is determined by the difference between a given desired value determining the nominal lamp operating voltage and an actual value dependent upon the instantaneous lamp operating voltage. In parallel with the lamp (1) a heating element (5) is arranged which is in thermal contact with a temperature-dependent electrical element (6), which produces the actual voltage dependent upon the instantaneous lamp operating voltage.

Circuit arrangement for adjusting the operating voltage of high-pressure

An electrode having a self-supporting cylindrical open coil of tungsten or molybdenum wire having a lead wire of tungsten or molybdenum passed coaxially through the coil and connected thereto. The turns of the coil engage each other. The central lead wire has a smaller diameter than the coil wire, this thin portion extending to a location just before the outermost turn of the coil.

Heatable electrode for high-pressure gas discharge lamps

A circuit arrangement for operating a high-pressure gas discharge lamp (3) with a pulsatory direct current produced from an alternating voltage supply (A, B) via a full-wave rectifier (1). The output of the full-wave rectifier is shunted by a series arrangement of a diode (4) and a capacitor (5). The capacitor (5) has a value of 10 nF to 1 .mu.F and a resistor (6), which is high-ohmic with respect to a current limiter (2) in series with the lamp (3), is connected in a current circuit between the end of the capacitor facing the diode and the lamp (3). As a result, a low re-ignition voltage is attained during the head-up phase of the lamp.

Circuit arrangement for operating a high-pressure gas discharge lamp

A circuit for operating high-pressure gas discharge lamps comprises a full-wave rectifier (2) which is connected to an alternating voltage supply source and supplies an output direct voltage to a combinatorial circuit part comprising a switching transistor (3), a choke coil (4), a fly-wheel diode (5) and a storage capacitor (6), from which the lamp is energized. A further combinatorial circuit part (7, 8, 10, 11) comprises at least one electronic circuit element (7) coupled between the storage capacitor (6) and the lamp (9) and is controlled by a control device (12). The control device compares an instantaneous lamp current of higher frequency with a nominal-value signal composed of a sinusoidal voltage component having double the supply frequency and a d.c. voltage component having a value of at least the maximum amplitude of the sinusoidal voltage.

Circuit arrangement for operating high-pressure gas discharge lamps

A circuit arrangement for A.C. operation of gas discharge lamps comprises a full-wave rectifier (1) connected to an alternating voltage source. The direct voltage is supplied to a combinatorial circuit part (3 to 8) in the form of a direct voltage converter, to which is connected a bridge circuit (9) which comprises four thyristors. The transverse branch of the bridge circuit includes the lamp (5). The full-wave rectifier (1) is followed by a smoothing capacitor (2) and an electronic switching element (14) is connected parallel to the bridge circuit (9). The switching element is switched to the conducting state in the vicinity of the zero passages of the input alternating voltage. As a result shortcircuits in the bridge circuit are avoided.

Circuit arrangement for A.C. operation of gas discharge lamps

A circuit arrangement for igniting and operating gas discharge lamps comprises a choke coil (1) connected between a lamp (2) and an a.c. supply source. The choke coil has an inductance L and an ignition device (3) is connected to the lamp. A capacitor (9) having a capacitance C is connected in parallel with at least a part of the choke coil in order to pass an ignition current to the lamp that is higher than the normal lamp operating current. The relationship betweeen the capacitive reactance of the capacitor and the inductive reactance of the choke coil is 1/.omega.C&gt;3.omega.L.

Circuit arrangement for igniting and operating gas discharge lamps

A circuit arrangement for operating high-pressure gas discharge lamps (6) with a current of higher frequency comprising a switching mains section including a switching transistor (4) and a control device (9), in which an upper and a lower reference current level (O,U) are produced. The switching transistor is switched to the non-conducting state when the lamp current exceeds the upper level (O) and is switched to the conducting state when this current falls below the lower level (U). The interval between the reference current levels (O,U) is more than 10% of the average lamp current and a further intermediate reference current level (M) is provided at which the switching transistor is switched each time at a predetermined number of passages of the lamp current through the intermediate reference current level.

A circuit arrangement for starting and operating a high-pressure gas discharge lamp having an outer starting electrode connected to an igniter. A full-wave rectifier (1) is connected to an alternating voltage supply (A, B) and has an output shunted by a series arrangement of a diode (4) and a capacitor (5). The capacitor is discharged in part through the lamp (3) after each half period of the alternating voltage. A resistor (6), which is high-ohmic with respect to a current limiter (2), is connected in the current circuit between the end of the capacitor (5) facing the diode (4) and the lamp (3). Thus, starting of the lamp is facilitated.

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Aachen, Germany

Ralf Schafer