JPS634596A - Discharge lamp starter - 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 is a discharge lamp using a bimetal switch! ! l
This relates to the J device.

[Background Art] This type of discharge lamp starting device, as shown in FIG. 7(a),
A discharge lamp La connected to a power source E via a stabilizing element Ba
A bimetal switch Sw is connected between the secondary gA terminals awb of , via a diode D1 of #S1, and a first heater H, which bends the bimetal switch Sw in the opening direction in parallel with the diode D1 of @1. In addition to connecting a series circuit with the Zener diode Dz, the first heater H,
The bimetal switch S is connected via a series circuit of the second diode D2 and the resistor R1 between the connection light c of the zener diode Dz and the other end of the bimetal switch Sw.
It was constructed by connecting a second heater H2 that curves w in the opening direction.

FIG. 7(b) shows the structure of the bimetal switch Sw, where each heater H, H2 is connected to a bimetal piece B.
,, B2 is heated and curved in the same direction (arrow), and A'c is the two bimetal pieces B2.
Contacts S, , S2 of B2 are idle, and after the lamp is lit, the amount of heat generated by heater H1 exceeds, and contacts S,, S2 become rfli.
However, when the lamp is not lit, the heat generated by the heater H2 prevails and the contacts S, S2 are closed.

In the above configuration, when the power is turned on, a preheating current flows to the lamp La through the first diode D1 and the bimetal switch SII+ during the positive half cycle of the power supply voltage, and a preheating current flows to the lamp La through the Zener diode Dz during the negative half cycle.
Since current is supplied to the heater H9 (for opening), the heat generated by the heater H1 opens the bimetal switch SII+ and starts the lamp La. After starting, a, bIl
@-4D only in the positive half cycle as the lfl voltage drops to the lampf lighting voltage.

A current flows along a path of →H1→D2→R1→H2→b, and at this time, the voltage applied to the disconnection heater H1 is made constant by the Zener diode Dz. Also, the heat generation amount of the second (closing) heater H2 at this time is set low, so the bimetal switch Sw
The open state is maintained due to the difference in the amount of heat generated between the two. If starting fails or starts immediately after the light goes out, the contact remains open and a.

5, the voltage across the closing heater H2 increases, but the voltage across the opening heater H4 remains constant as it remains constant, so the bimetal switch Sw is forcibly closed. , supplies a reheating current to the lamp La.

When the bimetal switch Sw closes, the closing heater H
The bimetal switch Sw It opens immediately, thereby restarting the lamp La.

In the conventional example described above, when lighting fails and the bimetal switch Sw closes due to the heat generated by the closing heater H2, the ayb opening is short-circuited by the first diode D and the bimetal switch Sw. As a result, the closing heater H2 immediately stops generating heat, and the contact 5t-82 opens again in a short time. The time that this contact is closed, that is, the reheating time, is usually about 0.1 to 0.2 seconds, but this time is slightly insufficient for reheating the lamp.
Depending on conditions such as the ambient temperature, they have the drawback of not being able to restart easily or being prone to incomplete lighting (half-wave lighting). In this case, the reheating time is 0.4~
0.5 seconds is the most desirable value.

[Object of the Invention] The present invention has been made in view of the above-mentioned problems, and improves restart performance in a discharge lamp starting device using a bimetal switch by ensuring sufficient lamp preheating time during restart. The purpose is to

[Disclosure of the Invention] Accordingly, the present invention connects a bimetal switch consisting of two opposing bimetal pieces between the secondary side terminals of a discharge lamp connected to a power source via a stabilizing element, and connects the bimetal switch in series with the bimetal switch. A first heater is connected to the bimetal switch by bending the first bimetal piece in the opening direction, and a second heater is connected in parallel to the bimetal switch to bend the second bimetal piece in the closing direction. In a light starting device, the second bimetal piece has a snap property, and when the power supply voltage is applied to the heater of PIS2 and the bimetal switch is closed when the lamp is not lit, the temperature of the second bimetal piece decreases. This is characterized in that the return is slightly delayed due to the snap property, and the rMa of the contact is delayed by that amount, making it possible to extend the reheating time of the lamp.

[Embodiment] Fig. 1 shows an embodiment of the present invention, and the circuit configuration is the same as the conventional example shown in Fig. 7, except that the bimetal switch S
The novel point is that a concave curved portion P1 as shown in FIG. 2 is press-molded on the second (closing) bimetal piece B2 of -, thereby imparting snap properties. Figure 3 shows tJS2
This shows the relationship between the temperature of the bimetal piece B2 and the moving 12 chicks, and the temperature T2 when the bimetal piece B2 curves and the contact closes by performing a snap action,
Temperature T when the bimetal piece B2 returns and the contact opens
There is a difference between 1 and 1.

Now in Figure 1, ? When the It source E is turned on, a preheating current flows through the diode D1 and the first bimetal switch SvI during the positive half cycle of the power supply voltage, and a current flows through the Zener diode Dz to the first (opening) heater H during the negative half cycle. When the first bimetallic piece B1 bends and the contacts S, S2 open to start the lamp, the lamp lights up and the voltage between terminals a and b becomes a relatively low lamp voltage. , in the positive half cycle a→D1→
Current flows along the path H1 → D2 → R1 → H2 → b,
Since the amount of heat generated by the closing heater H2 at this time is small, the bimetal switch S buttock is held in the open state by the heat generated by the opening heater H5.

If the lamp fails to start at this time, the power supply voltage is applied to the opening terminals a and b, and the opening heater H5, which is regulated at a constant voltage,
The calorific value of the closing heater H2 increases compared to the calorific value of
The curvature of the bimetal piece B2 of ff12 becomes larger and the contacts S and tS2 are closed. By closing this contact, heater H3
Since the heat generation of the heater H2 stops at the same time as the amount of heat generated by the heater H2 increases, conventionally, the temperature of the bimetal piece B2 immediately decreases, and the contact occurs in a short time, σS1. However, in the configuration of the present invention, even if the temperature of the bimetal piece B2 decreases, the opening of the contacts S2, S2 is slightly delayed due to the above-mentioned snap property, so the lamp filament This will extend the reheating time of the engine and ensure a reliable restart.

In the embodiment shown in FIG. 4, a microswitch-type compression spring piece P2 is provided in place of the concave portion P shown in FIG. 2, thereby imparting snap properties to the bimetallic piece B2.

In addition, in the embodiment shown in FIG. 5, the function of the PISl heater H4 is shared between the contact opening heaters H, a and the contact opening holding heaters H, b at the time of initial startup, thereby completely preheating the lamp. After the lamp starts, the contacts are kept open due to the difference in heat generation between heater H2b for opening and closing heater H2, and when the lamp is not lit, the contacts are kept open due to the difference in heat generation between heater H2b for opening and closing Since the heaters H and b are kept at a constant voltage by the Zener diode Dz+ and C/D22, the amount of heat generated by the heater H2 is greater and closes the contact. The point that subsequent contact opening is delayed by the snap property is exactly the same as in the case of FIG. 1.

The embodiment shown in Fig. 6 has the same circuit configuration as Fig. 1, but the closing bimetal piece B is not gaping, and the opening bimetal piece B1 also has a recessed portion P as shown in Fig. 2. is provided to impart snap properties, and at the same time, the Zener voltage of the Zener diode Dz is set lower than in the case of FIG. With this configuration, the temperature of the heater H1 for keeping the contacts open after the initial start can be reduced! As shown by T in the l*3 diagram,
Since the temperature can be set lower than the temperature T2 at which the contacts are opened, the life of the heater H1 can be extended and the reliability of the bimetal switch Sw can be improved.

[Effects of the Invention] As described above, the present invention uses a bimetal switch consisting of two opposing bimetal pieces to switch the 1' upper first
The preheating current is cut off by heating the bimetallic piece, and when restarting, the second bimetallic piece is heated to close the contact, and this contact closure short-circuits the heater of the second bimetallic piece, causing the bimetallic In a discharge lamp starting device of a type in which the piece returns to interrupt the re-preheating current, the return of the second bimetal piece is delayed by an extremely simple configuration in which the second bimetal piece is given snap properties. Therefore, it has the advantage that it is possible to secure a sufficient amount of re-warming time, which has been insufficient in the past, and to reliably restart the engine.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of the device of the present invention, and FIG. 2 is a bimetal switch used in the same device.
) is a perspective view of the main part, (b) is a side view of the main part, (c) is a front view of the main part, FIG. 3 is an explanatory diagram of the same operation as above, and FIG. 4 is a perspective view showing another embodiment of the bimetal switch. , FIG. 5 is a circuit diagram showing another embodiment of the present invention, FIG. 6 is a circuit diagram showing still another embodiment, FIG. 7 (,) is a circuit diagram of a conventional example, and (b) is the same as above. FIG. 3 is a perspective view of main parts. E...AC power supply, Ba...stability element, La...lamp, Sv...bimetal switch, Hl...@1
heater, H2... second heater, B... first bimetal piece, B2... second bimetal piece. Agent Patent Attorney Ishi 1) Chief 7 Figure 1 1:50 Figure 2 Figure 3 Figure 4 Figure 5 DZ D2 Figure 7 (b)

Claims (1)

[Claims] (1) A bimetal switch consisting of two opposing bimetal pieces is connected between the secondary side terminals of a discharge lamp connected to a power supply via a stabilizing element, and a first bimetal switch is connected in series to the bimetal switch.
A discharge lamp starting device comprising: a first heater for curving a bimetal piece in an opening direction; and a second heater for curving a second bimetal piece in a closing direction in parallel with a bimetal switch. A discharge lamp starting device characterized in that the second bimetal piece has a snap property.