MXPA97003708A - Quick restorer with integr interruption timer - Google Patents

Abstract

The present invention relates to a single integrated circuit that combines both a reset ignitor and a digital timer switch, which generates high voltage pulses to prime and re-prime high intensity discharge lamps, including sodium lamps high pressure without generating excessive amounts of lime

Description

QUICK RESTORER WITH INTEGRATED INTERRUPTION TIMER BACKGROUND The invention relates to high intensity discharge lamps (HID). More specifically, the invention relates to the restoration of high pressure sodium lamps (HPS), which are a specific type of HID lamp, which uses a single integrated circuit design that combines an improved reset circuit with an interruption timer. . HID lamps are normally used for lighting large open spaces such as roads (ie, street lamps) and lights for construction sites. These lamps contain one or more gases. To illuminate the lamp, the gas inside the lamp must be ionized to conduct electricity. HPS lamps contain both sodium gaseous and xenon gas. Xenon gas is used in conjunction with sodium because xenon is easier to ionize than sodium, when the lamp is cold (ie, the operating temperature of the lamp is low). As the xenon gas is ionized, the relative concentration of the xenon gas begins to decrease (ie, the xenon gas pressure decreases) while the operating temperature of the lamp and the relative concentration of the sodium vapor begins to increase. Consequently, as the concentration of the sodium vapor increases, it becomes easier to ionize the sodium and, thus, illuminate the lamp. However, initiation of the ionization process requires priming aids, such as standard igniters and reset igniters. Both standard igniters and reset igniters initiate ionization by generating a series of high-frequency, high-voltage pulses through the base of the lamp. In general, reset igniters and standard igniters are well known to those skilled in the art. For example, U.S. Patent No. 4,745,341, issued to Herres in May 1988, describes a quick reset primer for high intensity discharge lamps; U.S. Patent No. 4,527,098, issued to Owen in June 1985, discloses a discrete primer for HID lamps; and US Patent No. 31,486 republished and granted to Helmuth in January 1984, describes the rapid priming of gas discharge lamps. Reset igniters and standard igniters operate similarly. Both are capable of priming a cold HPS lamp. Both prime an HPS lamp by supplying high voltage pulses (usually greater than 2,000 volts) through the base of the lamp. Both must generate pulses at the peak or near the peak of an input sine wave to generate enough energy and ionize the gas inside the HPS lamp. The main difference between standard igniters and reset igniters is that reset igniters produce a pulse that contains much more energy than a pulse generated by a standard ignitor. This allows the restriction igniters to re-prime hot lamps immediately. Normally, the voltage of an impulse generated by a reset ignitor is of the order of 7,000 volts. This energy, necessary to generate the high voltage pulses, is stored in one or more capacitors and the pulses are generated when the capacitors are discharged through a transformer (as will be explained in more detail herein). In terms of ignition or ignition performance, reset igniters are able to turn on HPS lamps much more quickly than standard igniters. Because the impulses generated by the reset igniters contain so much energy, the reset igniters can re-prime a HPS lamp even though the concentration of xenon gas is relatively low compared to the relative concentration of sodium vapor. Because the impulses generated by standard igniters do not contain as much energy, the standard igniters should wait for the HPS lamp to cool sufficiently and for the relative concentration of the xenon gas (ie the xenon gas pressure) to rise before they can turn on the lamp. Normally, standard igniters may require 40 seconds or more to re-prime an HPS lamp. In the past, both reset igniters and standard igniters were designed to continuously supply high voltage pulses to the base of the lamp, until the lamp was illuminated. This was problematic for several important reasons. First, the continuous supply of pulses causes electrical components, such as ballasts, cables and insulation, to wear out more quickly. Second, the voltage across the base of an illuminated lamp can, on occasion, exceed the expected voltage levels. By interpreting this abnormal condition as that of a lamp that is not illuminating, reset igniters and standard igniters in the past would have continued to supply pulses to the already illuminated lamp, resulting in a visible flicker of the lamp. Third, the HPS lamps enter a cyclic operating base for a period of time before the final failure of the lamp. The continuous supply of pulses causes the HPS lamps in the cyclic operation phase to oscillate forward and backward between an illuminated state and a non-illuminated state. In addition to being extremely annoying, this oscillation between an illuminated state and an unlit state makes it difficult for maintenance personnel to identify the HPS lamps that need replacing. To avoid the problems associated with the continuous supply of pulses, manufacturers introduced interruption timers. For example, an interrupt timer may generate a signal that turns off or disconnects the ignitor after a fixed period of time, as long as the fixed period of time is sufficient to allow the ignitor to re-prime the lamp. Also, interrupt timers typically allow igniters to start supplying additional pulses only after the input voltage is recovered (ie, they are turned off and then on again), thus preventing the HPS lamps from the phase of cyclic operation oscillate between an illuminated state and a non-illuminated state. Interruption timers, like reset igniters and standard igniters, are well known to those skilled in the art. For example, the Patent of the United States of America No. ,070,279, granted to Garbowicz on December 3, 1991, exhibits a lamp ignitor with a particular characteristic of automatic shutdown; U.S. Patent No. 4,962,336, issued to Dodd et al. on October 9, 1990, describes an ignitor deactivator for a HID lamp priming circuit with a deactivation means that is triggered after the passage of a predetermined amount of time; and U.S. Patent No. 4,896,077, issued to Dodd et al. on January 23, 1990, describes an ignitor deactivator for an HID lamp priming circuit that includes a means for monitoring the lamp contact and a deactivation means that is triggered when the lamp voltage exceeds a given threshold. In addition to the interruption timers, thermal cut-off or interruption devices are also well known to those skilled in the art. Thermal switches are mainly used to protect the ignitor. Specifically, thermal switches prevent the continuous generation of pulses when the ambient temperature surrounding the igniter pulse exceeds a predefined temperature threshold. The main disadvantage of thermal switches is that they are never completely deactivated. Once the lamp is cooled, the thermal switches allow the ignitor to start generating pulses. Therefore, thermal switches will not prevent a cyclically functioning HPS lamp from oscillating between an illuminated state and an unlit state, as explained above. Although reset igniters, standard igniters, and interruption or cutoff devices are, in general, well known in the art as described above, there are no prior designs incorporating either a reset ignitor or a timing cutoff device. digital in a single integrated design package. A single integrated design package provides several advantages. First, an integrated design requires fewer electrical conductors since the external electrical connections linking the two devices would no longer be necessary. Second, integrated designs are more reliable; therefore, they are less likely to fail under non-ideal conditions (for example, variations in ballasts, lamps, input voltages, and input voltage waveforms). Third, integrated designs are less expensive to manufacture. One reason why there were no previous designs that combine both an ignitor and a cutting device in a single integrated package is the amount of heat these two devices normally generate. In general, this is due to the use of high voltage resistors, which generate excessive amounts of heat, to help regulate the voltage level and timing or the timing of the high voltage ignitor pulses. If someone tries to integrate an ignitor with a cutting device using the existing circuit designs, the amount of heat generated by this device will likely result in an excessive number of lamps and lamp accessory failures for the reasons presented above. In addition, the excessive amount of heat generated by the conventional designs of reset ignitor and interrupt timer would actually prevent an effective combination of them in a single integrated package. This is because the individual components used, especially the storage capacitors used in the igniter circuitry, are highly sensitive to high ambient temperatures. As the ambient temperature approaches the nominal temperature of these components, the components are more likely to fail. By combining the igniter circuitry with the cut-off or interruption circuitry in a single integrated package, the effects of temperature on the individual components become more exaggerated, since heat dissipation is more difficult. Therefore, any component in the ignitor and / or circuit breaker circuit that produces an excessive amount of heat will exacerbate the problem. To better capture the problem, the ambient temperature inside an HID lamp housing, due to the heat generated by the ballast and the HID lamp accessories alone, is approximately 90 ° C. This temperature does not reflect the additional heat that would be generated by a reset ignitor circuit and an interrupt timer. If a conventional restriction igniter and interruption timer were combined in a single integrated package, the excessive amount of heat that would be generated by this device would cause the ambient temperature inside the housing of the HID lamp to rise significantly above 90 ° C and approaching or exceeding the rated temperature for conventional reset ignition components, such as metalized storage capacitors that have a temperature rating of approximately 125 ° C. Therefore, combining a reset igniter and a conventional interrupt timer in a single integrated package will result in an unacceptable number of failures due to excessive heat generation. Consequently, there is a real need to provide an ignitor, specifically, a reset ignitor and an interrupt device, specifically an interruption timer device, which generates less heat than the previous designs, making it possible to integrate these two distinctly different devices into one. only integrated design package to achieve the reliability, manufacturing and performance advantages that this design will provide as previously mentioned.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fast reset circuit and a digital timing interruption circuit that avoids the continuous supply of high voltage pulses to the base of a high intensity discharge lamp (HID). An object of the present invention is to provide a fast reset circuit and a digital timing interruption circuit that avoids the continuous supply of high voltage pulses to the base of a high pressure sodium lamp, a specific type of HID lamp, when the lamp is in cyclic operation or not working. Another object of the present invention is to provide a fast reset circuit and a digital timing interruption circuit that is capable of immediately repriming an HPS lamp, after a momentary loss of the arc due to voltage fluctuations or power outages. Yet another objective of the present invention is to provide a single integrated device that incorporates both the fast reset circuit and the digital timer interrupt circuit. Yet another objective of the present invention is to provide a single integrated device incorporating both the fast reset circuit and the digital timer switch, which dissipates less heat in order to minimize the time required to re-prime an HPS lamp. Another objective of the present invention is to provide a single integrated device that incorporates both the fast reset circuit and the digital timer interruption circuit, which dissipates less heat by regulating the voltage level and time of the high voltage reset pulses with a novel circuit design, instead of resistors of high ataje. Yet another objective of the present invention is to provide a single integrated device that incorporates both the fast reset circuit and the digital timer switch that dissipates less heat by limiting the number of high voltage pulses needed to re-prime the HPS lamp. In accordance with one aspect of the present invention, the above as well as other objectives are achieved by an electronic circuit for illuminating a HID lamp, comprising a reset ignitor circuit that generates a plurality of reset pulses to illuminate the HID lamp; and a digital timer switch that prevents the reset igniter circuit from generating the plurality of reset pulses after a delay period has elapsed, wherein the reset igniter circuit and the digital timer switch are combined into a single Integrated circuit. In accordance with another aspect of the present invention, an electronic circuit for controlling the generation of a plurality of reset pulses for an HID lamp, comprises a resetting ignitor circuit that generates the plurality of reset pulses; a digital timer switch that prevents the reset igniter circuit from generating the plurality of reset pulses after a delay period elapses; and a pulse control circuit that controls the reset igniter circuit in such a way that the reset igniter circuit generates the plurality of reset pulses, for at least a limited time interval, in order to minimize generation of heat; wherein the reset igniter circuit, the digital timer switch and the pulse control circuit are combined into a single integrated circuit.

BRIEF DESCRIPTION OF THE DRAWINGS The objects and advantages of the invention will be understood by reading the following detailed description in conjunction with the drawings, in which: Figure 1 shows the device for fast resetting of the switch with integrated timer in relation to the HPS lamp, the power input source and the ballast; Figure 2 is a circuit diagram of the fast reset circuit and integrated timer switch; and Figure 3 illustrates a sine wave input voltage and the high voltage pulses generated by the fast reset circuit and integrated timer switch.

DETAILED DESCRIPTION The present invention provides a quick reset and a digital timer switch in a single integrated device that has the ability to quickly re-prime a high intensity discharge lamp (eg, a high pressure sodium lamp) after a fluctuation in voltage or a complete loss of energy, generating a series of high voltage and high frequency pulses towards the base of the lamp without generating an excessive amount of heat. The present invention also provides the ability to prevent the reset portion of the device from emitting the aforementioned pulses after a predefined period of time, unless the input power is restored. Figure 1 illustrates the physical relationship between the power input source 10, the ballast 11, the lamp 12 and the fast reset circuit 13 and integrated timer switch referred to below as the "IRRTC"). Figure 2 illustrates the design of IRRTC circuit 13. The IRRTC circuit 13 can be divided into five functional parts. First, the digital timer circuit MI has a time constant associated with it, whose value is determined by the resistors Rl and R4 and the capacitor C6. The second place, the reset circuit includes an auto-transformer TI, the capacitors C3 and C4, the resistor R6 and the SIDAC Z2. Third, the reset pulse control circuit includes a DI diode and a TRIAC Ql. Fourth, the protection circuitry for the reset pulse control circuit includes capacitor Cl, resistor R2 and varistor XI. Fifth, the energy regulation circuit for the MI circuit with digital timer includes the resistor R5, the capacitors C2 and C5, the diode D2 and the zener diode Zl. In an exemplary embodiment of the present invention, the components of the IRRTC circuit 13 have the following values. However, someone skilled in the art will recognize that this list of values is exemplary.

The operation of the IRRTC circuit 13 will be described below. Initially, the HPS lamp 12 is not illuminated and the line voltage 10 causes the input energy 14 to be applied to the IRRTC circuit 13. In an exemplary embodiment, the line voltage 10 is 120 volts RMS or 170 volts from peak to neutral. The application of the input energy 14 to the IRRTC 13, in turn causes the reset circuit to start generating high voltage pulses through the base of the lamp 12. The application of the input energy 14 also causes the MI circuit of the digital timer start the "delay" of the reset circuit. The digital timer circuit MI contains a voltage comparator with a specific time constant that defines the length of the delay period. During the delay period, the IRRTC circuit 13 applies, as mentioned above, high voltage pulses through the base of the HPS lamp 12. When the delay period elapses, the digital timer circuit MI prevents the circuit from of reset apply additional pulses until the voltage of the power line 10 recovers (ie, it is turned off and re-understood). Since the line voltage is not interrupted when and if the HPS 12 lamp enters its cyclic operation phase or when the HPS 12 lamp simply melts, the IRRTC circuit 13 will not attempt to re-prime the HPS 12 lamp, avoiding this so that the HPS lamp oscillates between an illuminated state and a non-illuminated state.

As stated above, the delay period is based on the value of the time constant associated with the voltage comparator inside the digital timer circuit MI. In turn, the time constant depends on the specific values of Rl, R4 and C6. While the values shown in the above table are exemplary, other values may be used as long as the delay period provides a sufficient amount of time to re-prime the HPS lamp 12. Using the above exemplary values, the delay period shall be about 5 to 10 minutes. Under normal conditions, 5-10 minutes are more than enough to re-prime the HPS lamp 12. During the delay period, the digital timer circuit MI provides an output signal on the tip 3, through R3, towards the TRIAC Ql. When this output signal is present, Ql turns on and the reset circuit is active. After the passage of the delay period, the output signal of the digital timer circuit is absent, Q1 is no longer conductive and the reset circuit is deactivated. To prolong the life and reliability of the TRIAC Ql, it is necessary to use some means to protect it against transient currents and overloads that exceed its classification. For example, the maximum dv / dt and the peak voltage when Ql is off (ie, it is not conductive), di / dt maximum when Ql will be turned on and the peak current when Ql is fully on (ie, is conductive) . The protection is provided specifically by placing a safety circuit in parallel with the TRIAC Ql. The safety circuit is comprised of Cl in series with R2. Functionally, Cl limits dv / dt to avoid unintentional firing while R2 prevents excessive di / dt when Ql is conductive. Also, Cl absorbs energy from voltage peaks. In general, safety circuits are well known in the art. In addition, of the safety circuit, the oxide / metal varistor XI provides additional protection for Ql. The regulation of the power to the digital timer circuit MI will be described in more detail below. As mentioned above, the energy regulation circuitry for the digital timer circuit MI includes R5, D2, Z1, C5 and C2 (see Figure 2). More specifically, R5 in combination with D2 serves as a simple half-wave rectifier that provides voltage to the tip 4 and tip 8 of the digital timer circuit MI during the positive half of the input voltage sine wave. During the negative half of the sine wave of the input voltage, C5 (which is charged during the positive half of the sine wave of the input voltage) is discharged, thereby maintaining the voltage across the spikes 4 and 8. Although The input voltage is 120 volts RMS, Zl acts as a voltage regulator limiting the voltage through pin 4 and pin 8 to 10 volts. In addition, C2 filters the unwanted impulses. Therefore, the digital timer circuit MI continuously receives a 10-volt input signal as long as there is no interruption in the line voltage 10. As long as the digital timer circuit Mi continues to receive this supply of 10 volts. it will not reset itself, and will continue to prevent the reset circuit from generating pulses through the base of the HPS lamp 12 after the delay period elapses. The reset circuit and the generation of high frequency and high voltage pulses will be described in more detail below. The IRRTC circuit 13 stores, in the capacitors C3 and C4, the energy it needs to produce high voltage pulses through the base of the lamp 13 (ie, the output 15). The capacitors C3 and C4 and the inductance associated with TI form a resonant circuit, where TI actually produces a burst of high voltage pulses 14 (ie, the resonant effect), as illustrated in Figure 3, when the stored energy in the capacitors it is downloaded. Of course, C3 and C4 will only be downloaded when the SIDAC Z2 is a driver. The SIDAC Z2 starts to drive as soon as the voltage across its terminals exceeds a specific threshold value. In the exemplary mode, this threshold is approximately 120 volts. The SIDAC Z2 will continue to drive until the current through the device drops below a specific level. In the exemplary embodiment, this will occur when the current is approximately 60 milliamps or less. As stated above, the high voltage pulses must have sufficient energy to ionize the gas contained inside the HPS lamp 12, so that the lamp 12 is conductive (ie illuminated). For the pulses to contain sufficient energy, the IRRTC circuit 13 must generate them at the peak or near the peak of the input voltage sine wave 15 (ie, between 65 ° and 110 ° or between 245 ° and 290 °), depending on it is illustrated in Figure 3. IRRTC circuit 13 controls this in the following way. During the negative half of the sine wave 15, the voltage builds back up to 120 volts at about 225 ° (or 45 ° after crossing the zero voltage). At this point, Z2 starts to drive. The exact time that the pulses 14 occur depends largely on the load on C3 when Z2 starts to drive and the time it takes for C4 to charge through R6 after Z2 starts to drive. However, as shown in Figure 3, pulse burst 14 is generated at approximately 225 ° in the sine wave of the input voltage. In the previous designs, high-watt resistors are used instead of DI and Ql to control the synchronicity of high-voltage pulses. With high-watt resistors, pulses are usually generated at the peak of the sine wave (ie, 90 °). However, as explained above, high-wattage resistors generate an excessive amount of heat and the use of these resistors will prevent one from effectively combining the reset and switch devices with digital synchronizer into a single integrated circuit. Therefore, the present invention employs Di and Ql, which generate significantly less heat, instead of high-wattage resistors. During the positive half of the sine wave 15 of the input voltage, the voltage again accumulates but the conduction through Q1 will be blocked by DI. Therefore, the IRRTC circuit 13 does not produce a burst of pulses during the positive half of the sine wave. Although a single pulse 16 during the positive half of the sine wave is possible (Figure 3), the overall effect is to reduce the total number of pulses through the base of the HPS 12 lamp. Therefore, DI and Ql help new to reduce the ambient temperature of the lamp caused by excessive emission of impulses. Once the delay period ends, the digital timer circuit MI prevents Ql from driving. As a result, the reset circuit is deactivated, the capacitors C3 and C4 no longer charge and the discharge through IT and TI no longer produces high voltage pulses through the base of the lamp 12. Although only the preferred embodiments are Illustrated and described specifically herein, it will be appreciated that many modifications and variations of the present invention are possible in light of the foregoing teachings and within the scope of the appended claims, without departing from the spirit and intended scope of the invention.

NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following is claimed as property:

Claims (16)

1. CLAIMS: l.An electronic circuit for illuminating a HID lamp, comprising: a resetting igniter circuit that generates a plurality of reset pulses to illuminate the HID lamp; and a digital timer switch that prevents the reset igniter circuit from generating the plurality of reset pulses after a delay period elapses; where the reset igniter circuit and the digital timer switch are combined into a single integrated circuit.
2. 2. The electronic circuit according to the claim 1, further comprising: a pulse control circuit that minimizes heat generation by controlling the reset igniter circuit, such that the reset igniter circuit generates the plurality of reset pulses for at least one time interval limited.
3. 3. The electronic circuit according to the claim 2, wherein the at least one limited time interval corresponds to at least one half negative wave of a sine wave of the input voltage.
4. 4. The electronic circuit according to the claim 2, wherein the pulse control circuit comprises a diode in series with a TRIAC.
5. 5. An electronic circuit for controlling the generation of a plurality of reset pulses for an HID lamp comprising: a reset igniter circuit that generates the plurality of reset pulses; a digital timer switch that prevents the reset igniter circuit from generating the plurality of reset pulses after a delay period elapses; and a pulse control circuit that controls the reset igniter circuit, such that the reset igniter circuit generates the plurality of reset pulses for at least a limited time interval, in order to minimize generation of heat; wherein the reset igniter circuit, the digital timer switch and the pulse control circuit are combined into a single integrated circuit.
6. The circuit according to claim 5, wherein the resetting igniter circuit comprises: first and second storage capacitors for storing energy to generate the plurality of reset pulses; a resistor in parallel with the second storage capacitor for charging to the second storage capacitor; an autotransformer having an inherent inductance that forms a resonant circuit with the first and second storage capacitors, such that the resonant circuit generates the plurality of reset pulses; and a SIDAC that triggers or activates the resonant circuit to generate the plurality of reset pulses only when an input voltage level reaches a predefined voltage level.
7. The electronic circuit according to claim 5, wherein the pulse control circuit comprises a diode in series with a TRIAC.
8. The electronic circuit according to claim 7, wherein the at least one limited time interval corresponds to at least one half negative wave of a sine wave of the input voltage.
9. 9. An apparatus for controlling the illumination of the HID lamp comprising: means for generating a plurality of reset pulses for illuminating the HID lamp; and a means for preventing reset pulses after a delay period elapses, wherein the means for generating the plurality of reset pulses and the means for preventing the reset pulses are combined into a single integrated circuit.
10. The apparatus according to claim 9, further comprising: means for controlling the synchronization of the reset pulses, such that the means for generating the plurality of reset pulses generates the plurality of reset pulses for at least one limited time interval, thus minimizing the generation of heat.
11. The apparatus according to claim 10, wherein the at least one limited time interval corresponds to at least one half negative wave of a sine wave of the input voltage.
12. The electronic circuit according to claim 10, wherein the means for controlling the synchronization of the reset pulses comprises a diode in series with a TRIAC.
13. 13. An apparatus for controlling the illumination of a HID lamp, comprising: means for generating the plurality of reset pulses to illuminate the HID lamp; means for preventing the plurality of reset pulses after the delay period elapses; and a means for controlling the timing of the reset pulses, such that the means for generating the plurality of reset pulses generates the plurality of reset pulses for at least a limited time interval, minimizing in this way the generation of heat, wherein the means for generating the plurality of reset pulses, the means for preventing the plurality of reset pulses and the means for controlling the synchrony of the plurality of reset pulses are combined into a single integrated circuit .
14. The circuit according to claim 13, wherein the means for generating the plurality of reset pulses comprises: first and second energy storage means for storing energy and generating the plurality of reset pulses; an inductive means forming a resonant circuit with the first and second storage means, such that the resonant circuit generates the plurality of reset pulses; and a switching means for driving or firing the resonant circuit to generate the plurality of reset pulses when the level of the input voltage reaches a predefined voltage level.
15. 15. The apparatus according to claim 13, in the means for controlling the synchrony of the plurality of reset pulses comprises a diode in series with a TRIAC. The electronic circuit according to claim 15, wherein the at least one limited time interval corresponds to at least one half negative wave of the 'sinusoidal wave of the input voltage.