JPS63250092A - Discharge lamp lighter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a starting device for a discharge lamp lighting device.

[Background technology]

Conventionally, this type of discharge lamp starting device, as shown in FIG. In between, the bimetal switch S is connected via the first diode D1.
A series circuit of a first heater H1 and a Zener diode D11 that bends the bimetal switch Sw in the opening direction is connected in parallel with this first diode D1, and a series circuit of a first heater H1 and a Zener diode D11 is connected in parallel with this first diode D1. Di
A second heater which bends the bimetal switch Sw in the closing direction is connected between the connection point C and the other end of the bimetal switch Sw through a series circuit of a second diode D and a resistor R1. A preheating control means 1 is constructed by connecting H2.

Part 8) shows the structure of a bimetal switch Sv, in which each heater H1+H2 is made up of a bimetal piece B1. B! The bimetallic pieces Bl and B are configured to be heated and curved in the same direction.
, contacts S1 + SR are closed, and after the lamp is lit, the heat generation amount of heater H1 prevails and the contacts are kept open, but when the lamp is not lit due to a startup error etc., the heat generation amount of heater H2 prevails. contact S1. S2 is closed. Note that by using bimetal pieces with the same characteristics, the effects of changes in power supply voltage and ambient temperature can be compensated for.

In the above configuration, when the power is turned on, a preheating current flows to the lamp La through the first diode D and the bimetal switch Sw in the positive half cycle of the hot water voltage, and a preheating current flows to the lamp La through the Zener diode Dz in the negative half cycle. (For opening) Since current is supplied to the heater If, the heat generated by the heater H1 opens the metal switch Sw and starts the lamp La. After starting, the mold pressure between a and b becomes 1 The voltage drops to the lighting voltage, and the positive half current /I/&→(DI
)→H1−+D2→R, −+Hg→b, current is supplied to both heaters, and the voltage applied to the disconnecting heater H1 is made constant by the Zener diode Dz. Further, the amount of heat generated by the second (closing) heater H2 at this time is set low, and therefore the bimetal switch Sw is held in the open state due to the difference in the amount of heat generated between the two heaters H, , H,. When starting fails or when starting immediately after turning off the light, the contact remains open and the mold pressure between a and b increases, so the voltage across the closing heater H2 increases, but the opening heater Since the voltage of H1 is constant and does not change, the bimetal switch Sv is forcibly closed and supplies reheating current to the lamp La. When the bimetal switch Sw is closed, the current supply to the closing heater H2 is stopped and the second bimetal piece B2 is closed. As the temperature decreases, the energization to the separation heater H1 slightly increases and the first
Since the bimetal switch Bs is further curved, the bimetal switch immediately opens, thereby causing the lamp L.
a is restarted.

Therefore, in the conventional example configured in this manner, when the lamp L& fails to start or when restarted immediately after being turned off, the bimetal switch Sv is forcibly closed.
Lamp L turns on in the same way as when starting immediately after turning on the power.
Although it has the effect of restarting the lamp A, if the lamp La becomes unable to light up at the end of its life (emissionless state), the starting device will repeat the restart operation as described above,
The contact life of the bimetal switch Sw is short, and in the worst case, the contact f8 may be damaged and the preheating current continues to flow, causing a problem that the stabilizing element Ba such as the choke coil generates abnormal heat.

[Purpose of the invention]

The present invention has been made in order to improve the above-mentioned problems, and its purpose is to provide a discharge lamp lighting device that can extend the life of the contacts and constitute a highly safe starting device in a small size and at low cost. It's about doing.

[Disclosure of the invention]

The present invention relates to a lamp such as a fluorescent lamp in which one end of both fifments is connected to both ends of an AC power source via a stabilizing element such as a choke coil/l', and a normally closed lamp connected between the non-power side ends of both fifments. a bimetallic switch including a first heater inserted in a current path from an AC gL source to the bimetallic switch and thermally coupled to the bimetallic switch, and an impedance member connected in parallel to the bimetallic switch. A second heater is thermally coupled to the first heater and supplies power to the first heater to keep the bimetallic switch open when the lamp is on, and to close the bimetallic switch again when the lamp is off. A discharge lamp lighting device comprising a preheating control means formed by supplying a second heater with electric power capable of bringing it into a closed state,
A protection means including a positive temperature coefficient thermistor is provided in the current path leading from the AC power supply to the bimetallic switch, and a heat retention means for suppressing heat radiation from the positive temperature coefficient thermistor is provided.

Therefore, if the starter device repeats the restart operation at the end of the lamp's life, causes contact welding, or if the preheating current flows for a long time due to short-circuiting of parts for some reason, or if the preheating current flows excessively, When a large current flows, the current flowing to the starter device is immediately suppressed, preventing deterioration of the contacts and extending their lifespan.Additionally, the reliability of the contacts is further improved by adding a small and low-cost heat insulating means. This makes it possible to construct an extremely safe starting device that is small and inexpensive, and can prevent abnormal heat generation of stabilizing elements such as chiller coils.

(Example) Hereinafter, the present invention will be explained in detail based on examples.

FIG. 1 shows an embodiment of the present invention, and the same reference numerals are given to the same parts as in the conventional example, and the explanation of the structure of the same parts will be omitted. Therefore, the configuration different from the conventional example is to provide a positive characteristic thermistor PTC as a protection means 2 inserted in the current path from the AC power source E to the bimetallic switch Sw via a stabilizing element Ba such as a chiller coil, The present invention is equipped with a heat retaining means 3 configured to suppress heat dissipation from the characteristic thermistor PTC as much as possible, enhance the heat retaining effect, and further maintain the temperature at a high temperature.

The protection means 2 is composed of an electrical resistance conversion element whose resistance value increases when the temperature rises, and in particular is constructed using a positive temperature coefficient thermistor PTC, and as already explained in the conventional example, the starting device is restarted at the end of the life of the lamp La. If the starting operation is repeated and the preheating current continues to flow due to contact welding, the positive temperature coefficient thermistor PTC will suddenly generate heat due to self-heating after a predetermined period of time, as shown in Figure 2. By increasing the resistance value, as shown in Fig. 3, the preheating current flowing through the bimetal switch Sv of the starting device (current flowing through the contacts) is rapidly decreased, and the Jil amount of the first and second heaters H2 is decreased by 4. By reducing the frequency of opening and closing of the switch Sv as shown in FIG. 4, abnormal heat generation of the stabilizing element Ba such as a choke coil can be prevented. As shown in Figure 5, the frequency of opening and closing of the bimetal switch SW is low, and the current flowing through the contacts of the bimetal switch Sv is low.
It can be said that the lower the (preheating current), the longer the contact life.

Therefore, in order to extend the contact life at the end of the lamp life, it is possible to obtain a high effect even if the same element is used by increasing the temperature of the positive characteristic thermistor PTC to a high temperature and increasing the resistance value. be.

In addition, in a configuration using a positive temperature coefficient thermistor PTC in this way, when the impedance seen from the lamp La side of the starter device decreases for some reason, not only during the life of the lamp (
For example, even in the event of a short-circuit accident in electronic components, etc., the system operates effectively and has high stability.

As shown in FIG. 6, the heat retaining means 3 is constructed by surrounding a positive temperature coefficient thermistor PTC mounted on a printed circuit board 4 with a box body 6 integrally formed with an outer case 5, and is easy to work with and easy to maintain. It also has the effect of increasing the i-product effect.

Further, as shown in FIG. 7, a through hole 7 is formed in the printed wiring board 4 adjacent to the positive temperature coefficient thermistor PTC mounted on the printed wiring board 4.
It is configured to have a slit hole 8 and a slit hole 8 to improve heat conduction, and can be manufactured at low cost.

Note that the heat retaining means 3 is not limited to the embodiments described above; for example, it may be formed into a groove instead of the through hole 7 of the printed wiring board 4, or a heat insulating material such as glass wool surrounding the positive temperature coefficient thermistor PTC may be used. The heat dissipation of the positive temperature coefficient thermistor PTC can be improved by using a nickel wire with poor heat dissipation for the lead wire 9, or by minimizing the area of copper foil near the soldering point of the lead wire 9 on the printed wiring board 4. Needless to say, any configuration may be used as long as it suppresses the noise.

〔Effect of the invention〕

As described above, the present invention provides a protection means including a positive temperature coefficient thermistor in the current path from the AC power source to the pie metal switch, and also includes a heat retention means for suppressing heat radiation from the positive temperature coefficient thermistor.

Therefore, if the starter repeatedly restarts the lamp at the end of its life, if the contacts are welded, or if the preheating current flows for a long time due to short-circuiting of parts, When current flows, it quickly suppresses the current flowing to the starter device, preventing deterioration of the contacts and extending their lifespan.Additionally, the reliability of the contacts is further improved by adding a small and low-cost F heat insulation means. In addition, the present invention has the remarkable effect that an extremely safe start #J device that can prevent abnormal heat generation of stabilizing elements such as a ballast can be made small and inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIGS. 2 to 5 are explanatory diagrams of the same operation, and FIGS. 6 and 7 are perspective views showing an embodiment of the heat-retaining means. 8. 1al is a circuit diagram of a conventional example, the crest is a perspective view of the same essential parts as above, and FIG. 9 is a circuit diagram of a different conventional example. B&...stability element, E...power supply, Sw...bimetal switch, HI...first heater, H2...second heater, La...lamp, PTC...positive characteristic Thermistor, l...preheating control means, 2... protection means,
3... Heat retention means, 6... Box part, 7... Through hole, 8
...Slit hole, 9...Lead wire.

Claims (4)

[Claims] (1) A lamp with one end of both filaments connected to both ends of an AC power source via a stabilizing element, a normally closed bimetal switch connected between the non-power side ends of both filaments, and a bimetal switch from the AC power source. a first heater interposed in the current path and thermally coupled to the bimetallic switch; and a second heater thermally coupled to the bimetallic switch including an impedance element connected in parallel to the bimetallic switch; It is formed by supplying power to the first heater that can keep the bimetal switch open when the lamp is lit, and supplying power to the second heater that can close the bimetal switch again when the lamp is not lit. A discharge lamp lighting device comprising a preheating control means, in which a protection means including a positive temperature coefficient thermistor is provided in a current path from an AC power supply to a bimetallic switch, and a heat retention means for suppressing heat radiation from the positive temperature coefficient thermistor is provided. A discharge lamp lighting device characterized by: (2) A discharge lamp lighting device according to claim 1, characterized in that a heat retaining means is formed by providing a through hole, a slit hole, or a groove in a location adjacent to the member where the positive temperature coefficient thermistor is located. (3) The discharge lamp lighting device according to claim 1 or 2, characterized in that the positive temperature coefficient thermistor is surrounded by a box portion to form a heat retaining means. (4) Claims 1 to 3, characterized in that the lead wire of the positive temperature coefficient thermistor is made of nickel wire.
A discharge lamp lighting device according to any one of paragraphs.