DE102010031512A1 - Ballast e.g. electronic ballast, and lamp e.g. blow-out protected high pressure discharge lamp, combined system, has lamp designed such that no burner components leave lamp with power multiplied with safety factor during placement of burner - Google Patents

Abstract

The system has a blow-out protected lamp i.e. high pressure discharge lamp (1), comprising a space protection unit, and a ballast e.g. electronic ballast, which does not permit large power for large time. The lamp is designed such that no burner components leave the lamp with the power multiplied with a safety factor during placement of a burner. The ballast comprises a control unit and a device, which measures output current and output voltage and evaluates the power. The control unit switches off an output to the lamp when output power is exceeded for the large time.

Description

Technical area

The invention relates to a system comprising a lamp and a ballast according to the preamble of claim 1.

In particular, it is a halogen lamp which can stand and burst under high pressure during operation, or else a high-pressure discharge lamp with a quartz glass or ceramic burner and with a metal halide filling or amalgam filling.

State of the art

Space-protected lamps are intended, inter alia, for use in open luminaires. As the burner bursts, existing safety devices in the blast protected lamp ensure that the hot burner components can not escape from the lamp. There are many space-protected lamps with very different mechanical structure known. There are lamps that use a shroud, ie a thick-walled glass tube, as a protective device, see for example WO 2007/122522 , There are also modular lamps, see DE 103 36 282 , The protection device here consists of a second thick-walled glass bulb, which is slipped over the base lamp. In space-protected lamps with a thick-walled outer bulb outside the Einschmelzbereiches the Platzerschutz is ensured by the fact that the wall thickness of the piston outside the Einschmelzbereiches is sufficiently large.

In EP 1 632 984 For example, it is proposed to use a space-protected lamp in which a net of steel wire is drawn over the lamp with a thin-walled outer bulb. When bursting the burner, the piston is destroyed, but the network catches the fast burner components, so that they can not escape from the lamp.

Today, space-protected lamps are usually intended for use with magnetic ballasts. Because of various causes, eg. As material defects or manufacturing errors, it is possible that the electrodes bend over the life of the lamps or fall off. As a result, the electrodes have different temperatures and consequently different current densities, which means that in alternating current operation, a different current flows in one half-wave than in the other half-wave. This ultimately flows a DC current. When operating on a magnetic ballast, this DC current is limited only very slightly by the ohmic internal resistance of the magnetic ballast, with the result that more power coupled into the arc and thus the internal resistance of the lamp drops, causing a further increase in the AC and DC current leads, bringing in a short time, z. B. 5 s, the introduced into the burner of the lamp power, the gas temperature and thus the gas pressure greatly increased. Finally, the burner will burst due to the overpressure. This results in hot particles with masses of up to 1.1 g at temperatures of 1200 ° C and speeds of 50 m / s, which impinge on the protection device in the space-protected lamp and the space-protected lamp must be constructed so that the hot particles are not the lamp being able to leave.

The American National Standard ANSI also describes test methods and evaluation methods. In the safe test 10 lamps are tested, with all the burner should burst. The most reliable evaluation states that none of the tested lamps in the outer bulb should have a hole that allows the escape of burner components.

In EP 1632 984 introduces a device that uses a high-power laser that radiates onto the burner wall, destroying the burner. This laser should have a wavelength in the visible range, which is fulfilled by a frequency-doubled Nd-YAG laser, which has a wavelength of 532 nm. In the application example, this laser has a pulse duration of 3 ns, a linewidth of 250 MHz, a repetition rate of 30 Hz and a power of 100 mJ. A plano-convex, 500 mm focal length cylindrical lens is used to focus the laser on the surface of the torch.

Disadvantageous in the EP 1 632 984 Placed Platzer-protected lamp is that when operating on known ballasts without power limitation, it can not be guaranteed that in the event of Brennerburnen no hot burner components can escape from the outer bulb, as the burner components may have higher energies than the burst test, so that national safety regulations are not met ,

The space-protected lamps according to the prior art are dimensioned for operation with magnetic ballasts which, in the event of a fault, can be several times as large as the nominal power can be coupled into the burner, whereby the burner bursts due to a significantly increased gas pressure and thus very fast burner components arise. which requires a complex and therefore expensive protective device in the space-protected lamp, which ensures that the hot burner components can not escape from the lamp. The test method according to the state of Technology using a high power laser to destroy the burner is not applicable because there are no characteristic operating conditions for the ballast and the place-protected lamp that ensure safe operation, which in case of failure when the burner bursts ensures no burner components from the outer bulb can escape.

Presentation of the invention

It is an object of the present invention to provide a system of a ballast and a lamp according to the preamble of claim 1 which is characterized by suitable operating conditions, whereby it is achieved that the gas pressure in the burner does not become significantly higher than the rated gas pressure, whereby the Burner components resulting from burner bursting can not have significantly excessive speeds, which means that the protective devices can be dimensioned significantly weaker in the space-protected lamps according to the state of the art and novel types of space-protected lamps can be realized, and a burst test device and a burst test method with which the effect of the newly designed protective device Checked at the place-protected lamp.

Today electronic ballasts are available that operate a halogen lamp or a high pressure discharge lamp during stationary operation to a certain power. Even with the ignition and the start, especially of high pressure discharge lamps, certain current and power values are not exceeded.

Brief description of the drawings

1 Burner protected Shroud lamp using a Shroud as a safety device.

2 Protected modular lamp consisting of a base lamp and an additional thick-walled outer bulb.

3 Space-protected lamp, which ensures the Platzerschutz by a thick-walled outer bulb outside the Einschmelzbereiches.

4 Space-protected lamp, in which by a steel net, which is located around the outer bulb, the Platzerschutz is realized.

5 Electrical circuit for the burst test according to ANSI C78.387e 2003 ,

6 Schematic diagram of an electronic ballast for the operation of a high-pressure discharge lamp with a control unit and measuring devices for voltage and current.

7 Scheme of the burst tester with a rupture chamber, a laser and a ballast.

8th Distribution of the impact points of the laser on the wall of a cylinder-symmetrical ceramic burner.

Preferred embodiment of the invention

1 shows a known per se-protected high-pressure discharge lamp 1 with discharge vessel 2 and Shroud 3 both in an outer bulb 4 are housed.

2 shows another embodiment of a space-protected lamp 1 in which the Platzerschutz by a closed piston 5 inside the outer bulb 4 is taught.

3 shows another embodiment of a lamp 1 in which the Platzerschutz for the discharge vessel 2 This causes the wall thickness of the outer bulb 4 towards the top 5 sufficiently thick is chosen.

4 shows an embodiment of a lamp 1 in which the Platzerschutz by a network 9 made of steel wire over the outer bulb 4 is realized.

It must be proven by means of a burst protection test that the structure and dimensions of the protective device are suitable for preventing the hot burner components from escaping in the event of burner bursting. Standardization specifications introduce a device and method for the burst test and ceramic metal halide lamps. The high pressure discharge lamp to be tested 1 , the test object, are connected via a separating transformer TR and a magnetic ballast with the impedance L1 ( 5 ) and an ignition device ZG connected to the mains voltage of 230V. With the isolation transformer, the power is adjusted so that a power of 110% to 120% of the rated power of the lamp 1 after a certain burn-in time of at least 10 minutes.

Then, a second magnetic ballast with the impedance L2 to the magnetic ballast with L1 is connected in parallel by a switch S1. This ensures that a current significantly greater than the rated current flows through the lamp, which increases the power consumption typically by a factor of 5 to 20 as required by ANSI guidances against the rated power, which also increases the gas temperature and the gas pressure. The Impedance L2 ₂ should be chosen so that the burner bursts within 5 seconds.

For these burst tests, the lamp should 1 in a rupture chamber 15 are used, which prevents leakage of the fast burner components, in the event that the outer bulb of the lamp is destroyed. This bursting chamber should also be such that the resulting mercury and metal iodide vapors can be pumped out. For observation of the lamp during operation, this bursting chamber should have a window with a gray filter.

In 6 is the schematic diagram of an electronic ballast shown. It consists of an input stage in which the mains voltage UN is rectified and filtered. In a next stage, the rectified voltage is increased by a boost unit in the voltage value. The half-bridge circuit consisting of the switches S1 and S2 and the capacitors C1 and C2. The lamp electrode connected to the capacitors has about U _Z / 2 as a voltage, while the other electrode is alternately switched to GND or U _Z. At the lamp is thus a rectangular AC voltage, the z. B. has a frequency of 150 Hz. The ignition unit ignites the lamp. All units, including switches S1 and S2, are connected to the control unit.

The lamp voltage is evaluated by the control unit as the difference between U _S and U _C. The lamp current is measured as a voltage across the shunt resistor R _I and can only be measured during the time when S2 is closed. The control unit evaluates the power and regulates the intermediate voltage with the help of Boost unit such that the existing power corresponds to the rated power.

In the event that a lamp electrode breaks or bends and so that the electrodes have different temperatures and current densities, and thus different impedances for the two half-waves occur, due to the capacitive coupling of the lamp to the two electrodes GND and U _Z no significant DC Set the current. Should this reduce the lamp resistance and thus increase the power consumption, the control unit will reduce the intermediate voltage in such a way that the nominal power is restored.

In addition, the boost circuit can transmit only a limited power P _B. It would thus be possible to set the limit power P _G equal to this power P _B.

Another possibility is to program the control unit, the microcontroller, to switch off the lamp when a certain output power P _G which exceeds the time t _G is exceeded. In order to obtain sufficient safety, it is useful to test the measuring devices for their function and accuracy.

In US-A 5828185 An electrical circuit is described, which is preferably to be operated together with the high-pressure discharge lamp in one unit. This circuit contains as a control unit a microcontroller and a measuring device, with which the control unit is able to measure the current output power. In this circuit or an extended circuit, a function can be integrated, which ensures that the output power does not exceed a certain limit power P _G , when certain times t _{G is} exceeded.

In a known ballast for retrofit lamps, which is operated on a magnetic ballast and uses a microcontroller-controlled electronic circuit for reducing the lamp power and the ignition, the lamp current and the lamp voltage is internally measured and evaluated the performance. If a rectifying effect occurs during operation, whereby a significant DC current flows, which is not limited by the ohmic resistance of the magnetic ballast, then the power in the lamp increases. If the power measured by the microcontroller exceeds t _G , z. B. 41 ms, the power P _G , z. B. 110 W at a nominal power of 65 W, then the microcontroller turns off the lamp by the device for reducing the lamp power for at least one half-wave, z. B. 10 ms turns on. In the retrofit lamp is ensured by the lamp to turn off that for times greater than t _G a determined threshold P _G will not exceed.

The lamp often has suitable protection devices such as a Shroud, a second outer bulb or a thick-walled outer bulb outside the Einschmelzbereiches, which are dimensioned so that when operating the lamp at the maximum power P _G when bursting the burner no. hot burner components can escape from the lamp, and a ballast that is suitable for the operation of the halogen lamp or high pressure discharge lamp, with the lamp form a unit and can be referred to as a lamp with integrated ballast, or used separately from the lamp, the Ballast is connected via lines to the lamp, and a device and a method for the ballast with the output power of the ballast for times greater than t _G can not be greater than a limit power P _G , and a Test device with which the protection device of the halogen lamp or high pressure discharge lamp when operating on a ballast at the power P _G multiplied by a safety factor k _G , the burner is locally damaged or warmed up to cause bursting of the burner, and a test method, the test on several lamps and an evaluation is provided, with which it can be judged whether the protection device of the lamps is suitable that no hot burner components escape from the lamp when bursting of the burner.

According to the invention now Platzer-protected lamps are operated with an electronic ballast (ECG) with power limitation.

By operating the lamp with one of the mentioned ballast, wherein the output power for times greater than t _G does not exceed a value of P _G is achieved that the burner of a lamp can not burst by an excessive gas pressure. Nevertheless, there are still causes that a burner can burst during operation at the gas pressure associated with the limit power P _G : It is possible that the electrodes bend or fall in the burner and thus there is a local increase in the burner wall temperature. It is possible that there are small cracks in the burner wall. Likewise, over the life of the burner wall can be attacked by the filling components. These errors all lead to a weakening of the burner wall, which can eventually lead to breakage. Since the burner bursts when belonging to P _G gas pressure and not at significantly excessive pressures, the burner components are not so high speeds, which also required for Platzerschutz protections in the Platzer-protected lamp need not be designed so strong and thus are cheaper than Space-protected lamps, which are dimensioned for a burner burst at a significantly inflated gas pressure.

A significantly weaker protection device may mean that in the lamp in Shroud technique, the wall thickness of the arranged around the burner glass tube may be smaller, that in the lamp in modular design, the wall thickness of the outer bulb may be smaller than that of the lamp with the thick-walled piston outside the Einschmelzbereiches, the wall thickness outside the Einschmelzbereiches may be smaller.

In the following, a burst tester will be described.

The burst test is supposed to be in a rupture chamber 15 be performed ( 7 ), which has a pump-down opening 16 having. The lamps 1 should be baked at least 10 minutes in such a way that the lamp power at least the limit power P _G multiplied by a safety factor k _G corresponds. For this purpose, it is possible, the structure of the prior art with a separating transformer and a magnetic ballast 25 to use, the lamp power k _G · P _G z. B. is measured with a power meter. It is also possible to use an electronic ballast that is adjusted to the output power k _G · P _G and in which the lamp power is also measured with a power meter.

After the burn-in period, the burner, in particular the burner wall, must be damaged by a suitable device to such an extent that the burner bursts at the gas pressure associated with k _G · P _G. One of the possible devices would be the use of a laser 20 which preferably has a wavelength which is in the range of the transmission of the outer bulb and that by lenses 21 on the burner wall of the lamp 1 is focused. This laser beam should pass through a suitable window 22 be coupled into the rupture chamber. So that the laser can be focused on the burner wall without the burner wall being heated significantly, this laser should have a reduced-power function. Alternatively, an alignment laser can be used, which has the same beam path as the laser.

For a first test mode, the focal point of the laser should be adjustable on the burner surface. For this purpose, the lamp with its socket on an XYZ turntable 17 which is located in the rupture chamber. It is also possible to mount the laser on an XYZ table. Adjustable mirrors, lenses or beam splitters can also be used to set the course of the laser beam and the laser focus on the burner surface.

In a second test mode, it should be possible for the point of impact of the laser on the burner surface to change continuously during the heating time, thus ensuring that all locations on the burner wall are heated on average over time. This can be achieved by placing the lamp with its socket on an automatically adjustable XYZ turntable 17 is mounted.

The burst chamber should have a window with a gray filter to check the Lampeneinbrennens. The gray window in the bursting chamber should be such that the laser light scattered on internal surfaces does not leak laser light for operation at rated power. This can be achieved by a suitable filter, for. B. an interference filter can be achieved. Alternatively it is It is possible to close the window with a flap and to ensure by means of a door switch that the laser can only be set to full power after closing.

The following is a burst test procedure will be described.

The first test mode for the burst test uses the lamp in the burst box. The laser is adjusted with the XYZ turntable to the selected position on the burner wall and focused. The door of the rupture chamber is closed. The lamp is powered by a ballast 25 switched on and heats up over time of at least 10 min. At the end of the burn-in time, the lamp power k _G · P _{G should be} present, which can be checked by measuring the power meter. Through the window, the lamp operation can be checked. After closing the door from the window, the laser is switched on or switched to full power. The laser power is adjusted so that the burner of the lamp after a certain time, for. B. 10 s bursts.

On the one hand, for the burst test, the location on the surface of the burner wall should be selected, which when bursting produces burner components that have the highest energies and impulses and thus require the strongest protection of the SPL. On the other hand, the protection device in the Platzer-protected lamp will have weak spots that can be destroyed by burner components with smaller pulses and energies so far that burner components can escape from the outer bulb of the lamp.

Since neither the locations of the weak spots in the lamp nor the location where burner components are generated with maximum energy and momentum, all surfaces must be systematically tested. For this purpose, the burst test is carried out on a number of lamps, but at least ten lamps, with each test, the laser is focused on a different surface of the burner wall in such a way that uniformly in all lamps hit by the laser surface units on the burner surface are distributed over the entire burner surface.

For cylindrically symmetrical burners and lamps, it is to be expected that the wall thicknesses change only within the burner axis and the lamp axis.

Therefore, it is sufficient in the burst tests to focus the laser on different points on the burner axis, wherein the direction of rotation can be determined by the structure of the lamp, in particular the frame ( 3 ).

In 8th an exemplary arrangement of the focal points P1 to P6 of the laser is shown, the z. B. at an angle of 45 degrees to the frame. This is at the first lamp 1 the laser focuses on the point P1, on the second lamp on the point P2 and on until the sixth lamp, where the laser is focused on the point P6. The cylinder symmetry of the lamp is due to the frame structure ( 3 ) a bit disturbed. Therefore, it is necessary the Platzertests for several angles with respect to the frame, z. At 135 degrees, 225 degrees and 315 degrees, thus testing 24 lamps according to this application example. To achieve further safety, the number of burst tests on the axis and at different angles to the frame can be increased, with which then a total of z. B. is reached on 125 lamps.

With the second test mode and the automated XYZ turntable, it is possible to rotate the lamp during operation of the laser, thus approaching a greater number of angles with respect to the frame for a particular point on the axis, thus averaging over the various measurements the different angles can be achieved, whereby the Einstellaufwand is slightly reduced.

The burst tests are considered successful if none of the tested lamps leaked any burner components after the burner burst. It is also possible to use the advanced evaluations according to the American National Standard ANSI.

In the following, a space-protected lamp for operation on ballast with limit power will be described.

A space-protected lamp intended for operation on a ballast with a limit power P _G is constructed in such a way that the protective equipment present in the lamp, when operated on a ballast with the power k _G · P _G and the targeted weakening of the burner wall, which leads to the bursting of the burner, with a larger number of lamps, which are all weakened in different places, none at all for the exit of burner components from the outer bulb leads.

For the operation of the lamp on a ballast without power limitation, a shroud wall thickness of 1.7 mm is required to ensure the Platzerschutzes, see WO 2007/122522 , When operating with a ballast, which for times greater than t _G no benefits Greater than P _G , the wall thickness of the Shroud can be reduced to 1.2 mm to ensure the burst protection. For the other performance levels, similar reductions in Shroud wall thickness are possible.

A space-protected modular lamp consists of a base lamp with a ceramic burner and a quartz glass bulb with a wall thickness of 1.2 mm. To ensure the Platzerschutzes the base lamp is located in an outer protective flask made of toughened glass. For operation on a ballast without power limitation, a 150 W lamp must have an outer protective bulb with a wall thickness of 1.7 mm. If this lamp on a ballast, which is greater for times t _G not larger services P _G allows operated, then it is possible significantly to reduce the wall thickness of the outer protective piston z. B. to 1.2 mm.

A space-protected lamp with a thick-walled outer bulb, see DE-Az 10 2009 051 537 , And a burner made of ceramic used for the Platzerschutz an outer bulb preferably made of tempered glass, which has a small wall thickness in Einschmelzbereich, z. B. 1 mm, and outside the Einschmelzbereiches has a much larger wall thickness. When operating this lamp on a ballast without power limitation, an outer bulb is required at a power of 70 W, which has a wall thickness of about 3 mm, for example in the equatorial area, at the level of the burner. When operating this lamp on a ballast, which allows for times greater than _G no greater powers P _G , it is possible to use the wall thickness of the outer bulb in the equatorial area, at the level of the burner, of about 2.3 mm.

These application examples show that when operating a high-pressure discharge lamp on a ballast that for times greater than L _G does not allow greater powers P _G , the protection measures required for the Platzerschutz can be dimensioned significantly weaker, which leads to weight reductions and cost savings.

In the following a system of ballast and Platzergeschützter lamp will be described.

As shown, electronic ballasts are feasible that do not allow output power for times greater than L _G. Likewise, space protected lamps can be constructed so that when operating at maximum power P _G multiplied by a safety factor k _G, burner components can not leak out of the lamp.

The ballast and the arcing lamp are characterized by the marginal power P _G , and become a system with respect to burst protection. In many luminaires, the ballast and the lamp are installed separately, with which the system-mediating size, the limit power P _{G must} first be appropriately set and also communicated. From the side of the ballast, the limit power P _{G is} proposed, which can preferably comply with all ballasts. For an electronic ballast with 70 W rated power limit power, z. B. be set to 90W. For the lamp test, a safety factor k _{G is} defined, eg. B. 1.2, which provides sufficient security. Finally, the ballast is labeled, z. B. with the inscription, "Make sure that the lamp power does not exceed the value P _G ". For the SPF lamp, it is noted, "Lamp is only suitable for operation on a ballast that limits power to P _G ".

In the case of lamps with integrated ballasts, the ballast and lamp system mentioned is a unit. Thus, the marginal power P _G can be easily determined and, since the electronics and lamp form a unit also need not be further communicated. A labeling of the electronic lamp is not mandatory.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2007/122522 [0003, 0055]
• DE 10336282 [0003]
• EP 1632984 [0004, 0007, 0008]
• US 5828185 A [0032]
• DE 102009051537 [0057]

Cited non-patent literature

• ANSI-C78.387e-2003 [0016]

Claims (19)

System of ballast and lamp, wherein the lamp has a means for Platzerschutz, characterized in that the ballast is constructed so that it allows times greater than _G no power greater than P _G that the space-protected lamp is constructed so that in the Power P _G multiplied by a safety factor k _G when the burner bursts, no burner components leave the lamp. System according to claim 1, characterized in that the ballast is an electronic ballast comprising a control unit and a device which measures the output current and the output voltage or similar quantities which evaluate power and the control unit turns off the output to the lamp, if the output power P _G , for a time greater than t _{G is} exceeded. System according to claim 1, characterized in that the ballast is an electronic ballast that can provide from its electronic circuit no more than the output power P _G. System according to claim 1, characterized in that in the case of a surface-protected lamp according to the prior art, the protective device for the Platzerschutz is dimensioned so that when bursting the burner at the power P _G multiplied by a safety factor k _G, the resulting burner components in the outer bulb of the Lamp remain. System according to Claim 4, characterized in that burst tests are carried out for determining the dimensioning of the protective devices using a burst test device and a burst test method. System according to claim 5, characterized in that the burst tester includes a unit capable of locally weakening the burner wall. System according to claim 6, characterized in that for weakening the burner wall, a laser is used, which is focused with suitable units on the surface of the sample. System according to claim 7, characterized in that the burst tester includes a unit with which the point of impact of the laser on the surface of the burner can be adjusted. A system according to claim 8, characterized in that the unit for adjusting the location on the burner surface is an X-Y-Z turntable on which the lamp is mounted with the socket. System according to claim 7, characterized in that in the burst tester an automated X-Y-Z turntable is used. System according to claim 5, characterized in that after the burst test method at least 10 lamps are tested. System according to claim 6, characterized in that, according to the burst test method, each lamp is locally weakened at a different location on the burner wall, in such a way that across all lamps the surface elements on which the laser impinges on the burner surface uniformly over the entire burner surface are distributed. System according to claim 12, characterized in that according to the burst test method for burners and lamps with a cylinder symmetry with different lamps different locations on the axis of the burner, are weakened locally at each different directions of rotation with respect to the lamp frame. System according to claim 13, characterized in that after the burst test method in burners and lamps with a cylinder symmetry at different lamps different locations on the axis of the burner, heated, wherein the lamp rotates during laser heating and thus achieves a better angle-dependent distribution of the impact points becomes. System according to claim 5, characterized in that, according to the burst test method, the burst test is considered to be successful if, in the case of the lamps tested, there are holes in the outer bulb which allow burner components to exit. System according to claim 5, characterized in that the space-protected lamp is a lamp in Shroud technology in which the wall thickness of the Shrouds can be chosen significantly weaker than when operating on a ballast without power limitation. System according to claim 5, characterized in that in the space-protected lamp with a thick-walled outer bulb outside the Einschmelzbereiches this may have a less thick wall thickness in the area outside the Einschmelzbereiches when operated on the ballast without power limitation. System according to claim 1 or 2, characterized in that the system of ballast and lamp form a structural unit. System according to claim 1 or 2, characterized in that the ballast and the Platzer-protected lamp is an electronic retro-fit lamp operated with a magnetic ballast operated on the mains voltage.

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