JP3015080B2 - Switch with indicator light - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch with an indicator light that can confirm the operation state of a load.

2. Description of the Related Art Conventionally, in a switch with an indicator light of this type, a current transformer is inserted and connected to a main circuit, and an output is obtained from a secondary side of the current transformer in accordance with a magnitude of a load current. The display element was turned on.

[Problems to be Solved by the Invention] In such a conventional example, since a current transformer is used, manufacturing cost is increased, and the current transformer is
Since the secondary current differs depending on the magnitude of the primary current, there is a problem that the brightness of the display element changes.

The present invention has been provided in view of the above points,
An object of the present invention is to provide a switch with an indicator light for reducing a change in brightness of a display element due to a magnitude of a load current.

Means for Solving the Problems According to the present invention, a diode is connected in a bridge shape, and a diode is further connected in a forward direction between its DC output terminals to form a rectification block. An AC power supply, a load, and a switch are connected in series therebetween, and a pair of light emitting diodes are connected in parallel in opposite directions to form a display block connected between the AC input terminals. Is mounted on a separate printed circuit board, and the inside of the body of the switch body including the cover and the body is divided by insulating ribs to form a housing, and the switch opening / closing mechanism is provided in one housing. And a printed circuit board on which the rectifying block is mounted in the other storage part.

[Operation] By using the voltage drop of the rectifying block, the light emitting diodes of the display block are turned on with a small change in brightness, and the printed circuit board on which the rectifying block is mounted and the opening / closing mechanism are connected to each other. Is divided by the body ribs,
Insulation is ensured.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 shows a circuit diagram of the switch body A. The electrical circuit configuration is composed of a rectifying block 1, a display block 2, and a switch SW of an opening / closing mechanism. Rectifier block 1 connects the diode D ₁ to D ₄ like a bridge, further, the diode D ₁ and is connected to the anode of the diode D ₅ to the connection point of the cathodes of the D _4, the diode cathode of the diode D ₅ D It is connected to the connection point of the anodes of ₂ and D _3. That is, the diodes D ₁ to
Diode D ₅ further in the forward direction between the DC output ends of the D ₄ are connected. The display block 2 includes a pair of light emitting diodes LED ₁ and LED ₂ connected in parallel in the opposite direction, and a protection resistor R. The display block 2 is a rectifying block 1
Are connected between a and b between the AC input terminals. still,
A choke coil may be used instead of the protection resistor R.

The switch body A is interposed between the power supply V and the load L. Now, when the switch section SW is on, the diodes D _{1 to} D ₅ are alternating current power sources, so that a current in a solid line direction and a current in a broken line direction flow alternately. That is, in the positive half cycle of the AC power supply, as shown by the solid arrow,
The current flows from D ₁ → D ₅ → D ₃ → load L, and in the negative half cycle, the current flows from load L → diode D ₄ → D ₅ → D ₂ .
Then, since the voltage drop of the diode D ₁ to D ₅ is almost constant less affected by the magnitude of the load current, a-b
A constant potential difference always occurs between them. Therefore, this a-
Since the potential difference between b supplies a substantially constant current to the light emitting diodes LED ₁ and LED ₂ , the light emitting diodes LED ₁ and L
The brightness of ED ₂ does not change much, and becomes almost constant.

Here, the forward voltage drop per diode is about 0.7V. Also, the forward voltage drop of the light emitting diode is, for example, in the case of a gallium phosphorus element,
Since it is about 1.8 V and about 1.5 V in the case of a gallium aluminum arsenic element, it is necessary to connect three diodes in series in order to pass a current through the light emitting diodes LED ₁ and LED ₂ . When the present invention to connect the diode D ₁ to D ₅ as shown in FIG. 1, regardless of the direction of the load current, to flow in the same direction of the current in the diode D _5, the diode is a total of five may be.

However, when a series circuit of three diodes is connected in parallel as shown in FIG. 2 to turn on the light emitting diodes, a total of six diodes are required. That is, by connecting as shown in FIG. 1 of the present invention, one diode can be reduced.

By the way, in the case of a switch with a built-in semiconductor, when an element breaks down due to factors such as an inrush current at power-on, an induced lightning surge induced on a power supply line, and an electrostatic discharge received by a person during operation, the switch becomes non-conductive. Can be considered.

Figure 3 shows the current waveforms of the diodes D ₁ to D ₅ of the circuit of FIG. 1, the same figure (a) is the load current, the same figure (b) is a diode D _1, D ₃ current, the FIG. 3C shows the current of the diodes D ₂ and D ₃ , and FIG. 4D shows the current of the diode D ₅ . The diode D _5, compared to other diodes D ₁ to D ₄ current flows only one side of the half-cycle, a current flows over both half cycles, there is a high probability that the diode D ₅ is faulty and non-conductive. When the diode D ₅ becomes non-conductive, the entire rectifier block 1 becomes non-conductive, the load current will flow all the display block 2. This means that if the load current is within the rating of the light emitting diodes LED ₁ and LED ₂ , the switch body A can be used without any problem, but if the load current is higher than the rating, the light emitting diodes LED ₁ and LED ₂ fail and the switch body A Becomes non-conductive.

In this regard, in the case of the circuit as shown in FIG. 2 in which a plurality of diodes are simply connected in series and parallel, the probability that all of the diodes D _{1 to} D ₆ fail is constant, and if the diode D ₁ fails, and load current emitting diodes LED _1, LED ₂
If the light-emitting diodes LED ₁ and LED ₂ fail at the rated value or more, a half-wave rectified current flows as indicated by a broken line in the circuit. Since the rated current of the light emitting diode is as small as several + mA, the load current is usually higher than the rated current in most cases.

In such a state, the load L is adversely affected, and in the worst case, the load L may be broken or burnt, which is dangerous. However, according to the circuit configuration shown in FIG. 1 of the present invention, as described above, there is a high probability that the entire switch body A becomes non-conductive, and a failure occurs in a safe mode.

FIG. 4 shows a comparison between the load current of the switch body A of the present invention and a conventional switch with a built-in current transformer and the brightness of the light emitting diode. As is apparent from FIG. 4, the change in brightness of the switch body A of the present invention is smaller than that of the current transformer type regardless of the magnitude of the load current. Further, the resistance value of the protection resistor R is such that the light emitting diode
For a gallium-phosphorous element, about 100Ω is appropriate, and for gallium-aluminum-arsenic, about 400Ω is appropriate. Also,
When a choke coil is used instead of the protection resistor R,
The inductance is set so that the commercial frequency has the same impedance.

Next, a specific mechanism of the switch body A will be described with reference to FIGS. Body of switch body A is body 4
And a cover 5, and terminal portions 6 connected to external electric wires are formed on both sides of the body 4, respectively. The terminal portion 6 includes a substantially U-shaped terminal plate 7, a substantially S-shaped locking spring 8 for press-connecting a conductor of an electric wire to the terminal plate 7, and a release button 9 for releasing the electric wire. I have. An electric wire insertion hole 10 for inserting an electric wire and a release hole 11 for inserting a tip of a driver or the like to press the release button 9 are formed in the bottom of the body 4.

A rib 12 made of an insulating material is integrally protruded from a substantially central portion of the body 4, and storage portions 13 and 14 are formed with the rib 12 as a boundary. An opening / closing mechanism is housed in one storage unit 13. That is, the support plate 15 electrically connected to the one terminal plate 7 is disposed at the bottom of the storage portion 13, and the substantially U-shaped opening / closing body 17 swings on the protrusion 16 formed on the support plate 15. It is arranged freely. A movable contact 18 is fixed to one side surface of the opening / closing body 17, and a fixed contact 19 facing the movable contact 18 is provided on the other terminal plate 6.

A handle 21 is provided in the opening 20 of the cover 5, and the lower surface of the actuator 22 protruding from the lower surface of the handle 21 abuts on the upper end of the opening / closing body 17. The contacts 18 and 19 are opened and closed by operating the seesaw. The contacts 18, 19 constitute the switch section SW shown in FIG.

The diode D _{1 of the} rectifying block 1 is provided in the other storage portion 14.
To D ₅ and implements the protective resistor R or the printed circuit board 23 is OsameSo. Also, the light emitting diodes LED ₁ , L of the display block 2
The display body 24 integrated with the ED ₂ is mounted on another printed circuit board 25, and this printed circuit board 25 is fixed to the lower surface of the handle 21. And both printed circuit boards 23 and 25 are lead wires 26
Connected by Here, grooves 27 and 28 are formed in the printed circuit boards 23 and 25, respectively, and the lead wires 26 are slightly slackened from the soldered portions at the ends of the lead wires 26 so that the lead wires 26 are formed in the grooves 27 and 28.
It is fixed to. This is to prevent the soldered portion of the lead wire 26 from breaking even when the handle 21 is inverted. Further, the printed circuit board 23 and the terminal plate 7 are also connected by the lead wire 29.

The upper surface of the display body 24 of the printed circuit board 25 fixed to the handle 21 is located corresponding to the display hole 30 of the handle 21,
The load state can be visually recognized from the outside of the handle 21.

Here, the switch main body A of the present invention is formed in a size of one standardized wiring appliance module, and is detachably mounted on a standardized mounting frame. On both sides of the cover 5, locking claws 31 for attaching to a mounting frame are protruded laterally.

FIG. 9 shows a switch frame A with a plate frame 32 as a mounting frame.
The exploded perspective view when attaching to the plate frame is shown.
Reference numeral 32 denotes a size in which three switch bodies A each having the size of one standardized wiring appliance module can be mounted. still,
The body 4 of the switch main body A and the cover 5 are connected by an assembly frame 33, and the above-described locking claw 31 is formed on the assembly frame 33. A pair of locking holes 34 into which a pair of locking claws 31 of the switch body A are inserted and locked in one side piece of the plate frame 32.
Are formed. Further, a bending piece 35 that can be bent to the side is formed integrally with the other side piece of the plate frame 32,
The other locking claw 31 of the switch body A is inserted and locked into the pair of locking portions of the bending piece 35, so that the switch body A is detachably mounted on the plate frame 32.
Further, the plate frame 32 has a mounting hole 36 for screw insertion for mounting on a switch box embedded in the wall surface.

A decorative plate 37 is mounted on the front surface of the plate frame 32, and an engaging claw 38 is provided on the rear surface.
By fitting 38 into the engagement hole 39 of the plate frame 32, the decorative plate 37 is detachably attached to the plate frame 32. An opening 40 for exposing the handle 21 of the switch body A is formed in the decorative plate 37.

[Effect of the Invention] As described above, according to the present invention, a diode is connected in a bridge shape, and a diode is further connected in a forward direction between its DC output terminals to form a rectification block. An AC power supply, a load, and a switch are connected in series therebetween, and a pair of light emitting diodes are connected in parallel in opposite directions to form a display block connected between the AC input terminals. Is mounted on a separate printed circuit board, and the inside of the body of the switch body consisting of the cover and the body is divided by insulating ribs to form a storage part. A mechanism part is housed, and a printed circuit board on which the rectifying block is mounted is housed in the other housing part. By illuminating the light-emitting diodes of the display block with a small change in brightness, it can be manufactured at lower cost compared to the conventional method using a current transformer, and furthermore, the light-emitting diodes are illuminated by utilizing the voltage drop of the diodes. Therefore, the change in brightness of the light emitting diode due to the magnitude of the load current is small, and the printed circuit board on which the rectifying block is mounted and the opening / closing mechanism are separated by the body ribs, so This has the effect of ensuring the insulation between the switching mechanism through which the load current flows and the printed circuit board on which the rectifying block is mounted. In addition, each light emitting diode can be turned on in each of the positive and negative half cycles of the AC power supply with a simple configuration, and the number of used diodes can be reduced by using the diode in each half cycle. , Cost can be reduced.

Furthermore, since each of the display block and the rectifying block is divided and mounted on a separate printed circuit board, the display block for displaying is arranged near the outside, and the rectifying block is housed in the body. The size of the switch main body can be suppressed, and since each is mounted on a printed circuit board, it is easy to incorporate the switch main body into the switch main body and to connect them together.

[Brief description of the drawings]

1 is a circuit diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram of the above embodiment, FIG. 3 is an operation waveform diagram of the above embodiment, and FIG. 4 is a characteristic diagram showing load current and brightness of a light emitting diode of the embodiment. FIG. 5 is a cross-sectional view of the switch body, FIG. 6 is a plan view of the switch body with the cover removed, FIG. 7 is a perspective view of a main part of the switch, FIG. FIG. 9 is an exploded perspective view showing the construction state of the above. 1 is a rectifying block, 2 is a display block, 4 is a body, 5
Cover, 12 ribs, the housing portions 13 and 14, 23 printed board, D ₁ to D ₅ are diodes, LED _1, LED ₂ is a light emitting diode, A is switch body.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01H 9/16 H01L 33/00

Claims (1)

(57) [Claims] A rectifier block is formed by connecting a diode in a bridge shape and further connecting a diode in a forward direction between its DC output terminals to form an AC power supply, a load and a switch between AC input terminals of the rectifier block. Are connected in series, a pair of light emitting diodes are connected in parallel in opposite directions to form a display block connected between the AC input terminals, and each of the rectifying block and the display block is divided into separate printed circuit boards. In addition to mounting the switch, the inside of the body of the switch body consisting of the cover and the body is divided by a rib of insulating material to form a storage portion, and the opening and closing mechanism of the switch is housed in one storage portion and the other is installed. A switch with an indicator light, wherein a printed circuit board on which the rectifying block is mounted is housed in the storage section.