JPS5841676Y2 - 2-lamp light source device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-lamp light source device, and more particularly to a two-lamp light source device that can detect whether or not a spare lamp is disconnected while the main lamp is on.

Generally, in an endoscope light source device, there is a first lamp used for diagnosis and treatment of the endoscope, and a second lamp that is used as a backup lamp to continue diagnosis and treatment when the first lamp is disconnected.
It has a lamp.

FIG. 1 shows a circuit diagram of a conventional two-lamp light source device.

A transformer 4 is connected to both ends of a commercial power source 20, and a first lamp 8 and a second lamp 10 are connected between lamp lighting voltage terminals a, l) of the transformer 4 via a changeover switch 6.

The changeover switch 6 is normally pushed to the first lamp 8 side, and the
The lamp 8 is turned on and used for diagnosis.

If the first lamp 8 is disconnected, the changeover switch 6
is pushed down to the second ramp 10 side.

However, if the second lamp 10 is also broken,
Not only does the second lamp 10 not work as a spare lamp, but
It takes more time to replace the lamp, and if the light source is used as an endoscopic light source, it causes unnecessary pain to the endoscopic light source while changing the lamp.

Further, when a treatment is performed using a high-frequency electrocautery through an endoscope, interruption of illumination light may lead to a serious accident that harms the human body.

Therefore, in a two-lamp type light source device, it is essential to display whether or not the spare lamp is disconnected during use.

This idea was made to deal with the above-mentioned circumstances.
An object of the present invention is to provide a two-lamp light source device that can detect whether or not a standby lamp is disconnected while the main lamp is on.

Hereinafter, one embodiment of the two-lamp type light source device according to this invention will be described with reference to the drawings.

Figure 2 shows the circuit diagram.

A transformer 14 is connected to both ends of the commercial power supply 12, and a first lamp 18 and a second lamp 20 are connected via a changeover switch 16 between lamp lighting voltage terminals B and C at an intermediate point and one end of the transformer 14. It is connected.

Further, the first and second lamps 18, 20 are each connected to the neon tube lighting voltage terminal A at the other end of the transformer 14 through resistors 22 and 24 in series.

The connection points between the first and second lamps 18.20 and the resistor 22.24 are each connected to the anode side of a diode 26.28, and the cathode sides of the diodes 26 and 28 are connected in anti-series. via the transformer 14
It is connected to the lamp lighting voltage terminal C at one end of the terminal.

Here, the rating of the first and second lamps 18.20 is 15V.
, 150 W, the resistance 22.24 is 100 KQ, and the lighting voltage of the neon tube 300 is 30 V or more.The operation of the two-lamp type light source device configured in this way will be described below.

Assume that the changeover switch 16 is now turned to the first lamp 18 side.

The neon tube 30 is connected to a commercial power source A via a discharge resistor 22.
C100V is applied, but since the impedance of the transformer 14 is significantly smaller than the impedance of the resistor 22 (100V, Q), the terminal voltage of the first lamp 18 is 15V.

Further, if the second lamp 20, which is a spare lamp, is not disconnected, the impedance of the second lamp 20 is 1.5,
! It is about Q and the impedance of resistor 24 (100KΩ
), the terminal voltage of the second lamp 20 is almost 0.

Therefore, the voltage applied to both ends of the neon tube 30 becomes less than the lighting voltage, and the neon tube 30 does not light up.

Therefore, it is detected that the spare lamp is not disconnected.

Next, if the second lamp is disconnected, the second lamp 2
The impedance of zero becomes infinite, and AClooV is applied to the neon tube 30 through the discharge resistor 24 and diode 28, and the voltage applied to the neon tube 30 reaches the lighting voltage, so the neon tube 30 lights up and the preliminary lamp is disconnected. indicate.

Similarly, while the second lamp 20 is lit, if the first spare lamp 18 is not disconnected, the neon tube 30 is not lit, and if the first lamp 18 is disconnected, the neon tube 30 is not lit.
lights up, indicating whether or not there is a disconnection.

Here, the transformer 14 may be a separate transformer in which the primary winding and the secondary winding are insulated.

Next, a second embodiment of the two-lamp type light source device according to this invention will be described with reference to its circuit diagram shown in FIG.

Note that the same parts as in the first embodiment are given the same numbers in FIG. 3, and the explanation thereof will be omitted.

The second embodiment uses a light emitting diode 32 and a Zener diode 34 instead of the neon tube 30 of the first embodiment,
The light emitting diode 32 is the diode 2 connected in reverse series.
6.28 is connected in the forward direction, and the Zener diode 34
are connected in anti-series with the light emitting diode 32.

Here, it is assumed that the light emitting diode 32 emits light clearly at about 10 mA, the Zener voltage of the Zener diode 34 is 24 V, and the reverse breakdown voltage of the diode 26.28 is 20 V.
0 V, and its operation will be explained below.

Assume that the changeover switch 16 is now turned to the first lamp 18 side.

The terminal voltage of the first lamp 18 is 15■, but since the Zener diode 34 and the light emitting diode 32 are connected in reverse series, even if current tries to flow in the forward direction to the light emitting diode 32, the Zener diode 34 It is blocked by voltage (24V).

In addition, the current flowing in the reverse direction to the light emitting diode 34 also depends on the diode 26 having a reverse withstand voltage of 200 V and a commercial power supply of 100 V.
It is sufficiently higher that it is blocked by diode 26.

If the second lamp 20 is not disconnected, the terminal voltage of the second lamp 20 is almost 0, so no current flows through the light emitting diode 32.

Therefore, the light emitting diode 32 does not emit light, and it is detected that the preliminary lamp is not disconnected.

Next, when the second lamp 20 is disconnected, the impedance of the second lamp 20 becomes infinite, so the current flowing through the diode 28 is connected to the 24V Zener diode 34.
breaks down and flows in the forward direction through the light emitting diode 32, so the light emitting diode 32 lights up and the second lamp 2
Displays 0 disconnection.

This embodiment can also display whether or not the first lamp is disconnected while the second lamp 20 is lit.

As mentioned above, according to this invention, it is possible to detect the disconnection of the spare lamp in advance, so even if the main lamp is disconnected, the spare lamp will surely turn on and the illumination light will not be cut off.
A lamp-type light source device can be provided.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a conventional two-lamp type light source device, Fig. 2 is a circuit diagram showing one embodiment of the two-lamp type light source device according to this invention, and Fig. 3 is a circuit diagram showing another embodiment. . 12...Commercial power supply, 14...Transformer,
16...Choice switch, 18.20...
・Lamp, 22.24...Resistance, 26.28・
...Diode, 30 ...Neon tube, 3
2... Light emitting diode, 34... Zenada f-ode.

Claims (3)

[Scope of utility model registration request] (1) a first power supply unit having a lower voltage than the first power supply unit;
and a second power supply unit, one end of which is connected to one end of the first power supply unit, and one end of each of which is connected to the first power supply unit. The first one is connected to the connection point of the second power supply section. a second lamp; a first resistor connected between the other end of the first lamp and the other end of the first power source; and the other end of the second lamp and the other end of the first power source; a second resistor connected between the first and second resistors, and a second resistor connected to the other end of the second power supply unit to apply an operating voltage to the second resistor. a switching means selectively supplying the second lamp to the other end; and an anode side of the first lamp. The first lamp is connected to the other end of the second lamp, and its cathode sides are commonly connected in reverse series. a second diode; and the first diode. Second
The connection point of the power supply unit and the first connection point. A two-lamp light source device comprising: a display circuit connected between a common connection cathode of a second diode; (2) The two-lamp light source device according to claim 1, wherein the display circuit includes a neon tube. (3) The display circuit includes a light emitting diode whose anode side is connected to the connection point of the first and second diodes, and a cathode side connected in inverse series to the cathode side of the light emitting diode, and whose anode side is connected to the first and second lamps. A two-lamp type light source device according to claim 1, characterized in that it has a Zener diode connected to one end of the zener diode.