JPH052942A - Switch with indicator lamp - Google Patents

Abstract

PURPOSE:To lessen variation in the lightness of a display element depending upon the size of the load current by constituting a switch circuit without use of any current transformer. CONSTITUTION:A switch circuit is formed from a rectifier block 1, display block 2, and switch SW of a switch mechanism part. The rectifier block 1 connects diodes D1-D4 in the form of bridge, and the anode of another diode D5 is connected with the inter-cathode junction of the diodes D1 and D4, while the cathode of the diode D5 is connected to the inter-anode junction of the diodes D2 and D3. A display block 2 configured with two light emitting diodes LED1, LED2 in parallel connection oppositely and a protection resistor R is connected with the input/output end of the rectifier block 1. The switch mechanism part is accommodated in an accommodation part 13 approx. in the middle of the body, while the display block 2 is accommodated in the accommodation part of a steering wheel. Thereby the light emitting diodes can be lighted up through utilization of voltage drop in the diodes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch with an indicator lamp for confirming the operating state of a load.

[0002]

2. Description of the Related Art Conventionally, in a switch with an indicator lamp of this kind, a current transformer is inserted and connected to a main circuit, an output is obtained from the secondary side of the current transformer according to the magnitude of a load current, and the output is provided by the output. The display element was lit.

[0003]

In such a conventional example, since the current transformer is used, the manufacturing cost is high, and the secondary current of the current transformer is different depending on the magnitude of the primary current. There was a problem that the brightness changed.

The present invention has been made in view of the above points, and provides a switch with an indicator lamp for reducing the change in the brightness of the display element due to the magnitude of the load current. is there.

[0005]

According to the present invention, diodes are connected in a bridge shape and diodes are connected between midpoints of respective sides to form a rectification block, and light is emitted between input and output ends of the rectification block. A display block for connecting a diode is formed, and an opening / closing mechanism is installed in the body of the switch body including a cover and a body, and a display block is housed in the body of the handle.

[0006]

[Operation] Then, the voltage drop of the rectification block is used to light the light emitting diode of the display block with a small change in brightness, and the printed circuit board on which the rectification block is mounted and the opening / closing mechanism section are Is separated into a body and a handle to ensure insulation, and a printed circuit board is resin-molded to prevent breakage of the lead wire and peeling of the pattern due to shock or vibration.

[0007]

1 shows a circuit diagram of a switch main body A, which is composed of a rectifying block 1, a display block 2 and a switch section SW of an opening / closing mechanism section as an electric circuit configuration.

The rectifying block 1 includes diodes D1 to D4.
Are connected in a bridge shape, the anode of the diode D5 is connected to the connection point between the cathodes of the diodes D1 and D4, and the cathode of the diode D5 is connected to the diodes D2 and D
The three anodes are connected to each other.

The display block 2 is connected in parallel in the opposite direction.
Two light emitting diodes LED1, LED2 and protection resistor R
It consists of and.

The display block 2 is the rectification block 1
It is connected to the input / output terminal of. A choke coil may be used instead of the protection resistor R.

The switch body A is arranged between the power source V and the load L. Now, when the switch SW is on, the diodes D1 to D5 are AC power supplies, so that the current in the solid line direction and the current in the broken line flow alternately.

That is, in the positive half cycle of the AC power source, as indicated by the solid arrow, the diodes D1 → D5 → D3.
→ The load L and the current flow, in the negative half cycle, the load L and the current flow, and in the negative half cycle, the current flows from the load L → the diode D4 → D5 → D2.

Since the voltage drop across the diodes D1 to D5 is substantially unaffected by the magnitude of the load current, a constant potential difference is always generated between a and b.

Therefore, since the potential difference between a and b supplies a substantially constant current to the light emitting diodes LED1 and LED2, the brightness of the light emitting diodes LED1 and LED2 does not change so much and the brightness is almost constant. It becomes

The forward voltage drop per diode is about 0.7V.

The forward voltage drop of the light emitting diode is, for example, about 1.8 V in the case of gallium-phosphorus element.
In the case of gallium / aluminum / arsenic element, since it is about 1.5V, light emitting diodes LED1, LED
In order to pass a current through 2, it is necessary to connect three diodes in series.

In the present invention, as shown in FIG.
When 1 to D5 are connected, the current in the same direction flows through the diode D5 regardless of the direction of the load current, so that the total number of diodes is five.

However, in order to turn on the light emitting diode, when a series circuit of three diodes is connected in parallel as shown in FIG. 2, a total of six diodes are required.

That is, the number of diodes can be reduced by one by connecting as shown in FIG. 1 of the present invention.

By the way, in the case of a switch with a built-in semiconductor,
It is conceivable that the element may fail and become non-conductive due to factors such as an inrush current when the power is turned on, an induced lightning surge induced in the power line, and electrostatic discharge received by a person during operation.

FIG. 3 shows the diodes D1 to D of the circuit of FIG.
5 shows the current waveform of the diode 5, FIG. 5a shows the load current, FIG. 7b shows the current of the diodes D1 and D3, and FIG.
The currents of D2 and D3 and the current of the diode D5 are shown in FIG.

Since the current flows through the diode D5 over both half cycles as compared with the other diodes D1 to D4 through which the current flows only in one half cycle, the diode D5
There is a high probability that 5 will fail and become non-conductive.

When the diode D5 becomes non-conductive, the rectifying block 1 as a whole becomes non-conductive, and the load current all flows to the display block 2.

This is because the load current is a light emitting diode LED.
Switch main body A without any problem if it is within the rating of 1 and LED2
Can be used, but if the rating is exceeded, the light emitting diodes LED1 and LED2 fail and the switch body A becomes non-conductive.

In this respect, in the case of a circuit as shown in FIG. 2 in which a plurality of diodes are simply connected in series and parallel, the probability that all the diodes D1 to D6 fail is constant, and if the diode D1 fails and the load is high, When the current exceeds the rating of the light emitting diodes LED1 and LED2 and the light emitting diodes LED1 and LED2 fail, a half-wave rectified current as indicated by a broken line flows in the circuit.

The rated current of the light emitting diode is several tens of meters.
Since it is as small as A, the load current is above 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 burned, which is dangerous.

However, with 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 will become non-conductive, and a failure will occur in a safe mode.

FIG. 4 compares the load current and the brightness of the light emitting diode of the switch body A of the present invention and the conventional switch with a built-in current transformer.

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.

The resistance value of the protective resistor R is appropriately about 100Ω when the light emitting diode is a gallium-phosphorus element, and about 400Ω when the light-emitting diode is a gallium-aluminum-arsenic element.

Also, when a choke coil is used instead of the protection resistor R, the inductance is set so that the impedance becomes equivalent at the commercial frequency.

Next, a specific structure of the switch body A will be described with reference to FIGS. The outer shell of the switch body A is composed of a body 4 and a cover 5, and on both sides of the body 4, terminal portions 6 connected to an electric wire from the outside are formed.

The terminal portion 6 is composed of a substantially U-shaped terminal plate 7, a locking spring 8 for pressure-connecting the conductor of the electric wire to the terminal plate 7, and a release button 9 for releasing the electric wire.

An electric wire insertion hole 10 for inserting an electric wire and a release hole 11 for inserting the 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 projected at a substantially central portion of the body 4, and a storage portion 13 is formed with the rib 12 as a boundary.

An opening / closing mechanism is housed in the storage unit 13.
That is, the support plate 15 electrically connected to one of the terminal plates 7 is arranged at the bottom of the housing portion 13, and the substantially U-shaped opening / closing body 17 is swingable on the protrusion 16 formed on the support plate 15. It is located in.

A movable contact 18 is fixed to one side surface of the opening / closing body 17, and the fixed contact 1 facing the movable contact 18 is fixed.
9 is provided on the other terminal plate 6.

A handle 21 is provided in the opening 20 of the cover 5, and a spring 26 attached to the lower surface of an operator 22 protruding from the lower surface of the handle 21 abuts the upper end of the opening / closing body 17 to allow the handle 21 to move. The open-close member 17 is operated by a seesaw operation to open and close the contacts 18 and 19.

The contacts 18 and 19 form the switch section SW shown in FIG. Storage part 14 of the handle 21
A mold block 42 in which the printed circuit board 23 on which the diodes D1 to D5 of the rectifying block 1 and the protection resistor R are mounted is molded with a resin 41 is installed inside.

Further, the light emitting diode L of the display block 2
The display body 24 in which the ED1 and the LED 2 are integrated is mounted on a printed circuit board 25.
It is fixed to the lower surface of 1.

The printed circuit board 25 has a lead wire 29.
Connected by. Here, a groove 28 is formed in the printed circuit board 25, and the lead wire 29 is fixed to the groove 28 with a slight slack from the soldering portion at the end of the lead wire 29.

This is to prevent the soldered portion of the lead wire 29 from being broken even if the handle 21 is reversed.

Since the end portion on the printed circuit board 23 side is molded with resin 41, disconnection against impact, vibration, etc. is prevented.

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

Here, the switch body A of the present invention is formed to have a size of one standardized wiring device module, and is detachably mounted on the standardized mounting frame. There is.

On both sides of the cover 5, locking claws 31 for attaching to the mounting frame are provided to project laterally.

FIG. 9 is an exploded perspective view of the switch body A mounted on a plate frame 32 which is a mounting frame. The plate frame 32 is a standardized wiring device module 1.
The size is such that three switch bodies A each having a size corresponding to that of the switch body A can be mounted.

The body 4 and the cover 5 of the switch body A are
Are connected to each other by an assembly frame 33, and the engaging claw 31 is formed on the assembly frame 33.

A pair of locking holes 34 into which one pair of locking claws 31 of the switch body A are inserted and locked are formed in one side piece of the plate frame 32.

The other side piece of the plate frame 32 is integrally formed with a bending piece 35 capable of bending sideways, and the pair of locking portions of the bending piece 35 are provided with the other pair of the switch body A. The locking claw 31 is inserted and locked, and the switch body A is detachably mounted on the plate frame 32.

Further, the plate frame 32 is provided with a mounting hole 36 for inserting a screw for mounting on a switch box embedded in the wall surface.

On the front surface of the plate frame 32, the decorative plate 3
7, the engaging claw 38 is projected on the back surface, and by fitting the engaging claw 38 into the engaging hole 39 of the plate frame 32, the decorative plate 37 is attached to the plate frame 32. It is detachably attached.

Further, the decorative plate 37 has an opening 40 for exposing the handle 21 of the switch body A.

[0055]

As described above, according to the present invention, the diodes are connected in a bridge shape and the diodes are connected between the midpoints of the respective sides to form a rectifying block, and light is emitted between the input and output ends of the rectifying block. A display block for connecting a diode is formed, and an opening / closing mechanism is installed in the body of the switch body including a cover and a body, and a display block is housed in the body of the handle.

Therefore, by using the voltage drop of the rectifying block to light the light emitting diode of the display block with a small change in brightness, the light emitting diode can be manufactured at a lower cost than the conventional one using the current transformer.

Moreover, since the light emitting diode is turned on by utilizing the voltage drop of the diode, the change in brightness of the light emitting diode due to the magnitude of the load current is small.

Further, since the printed circuit board on which the rectifying block is mounted and resin-molded is separated from the opening / closing mechanism section, insulation between the opening / closing mechanism section through which a large load current flows and the printed circuit board on which the rectifying block is mounted is secured. This is an effect that can be achieved.

Further, since the printed circuit board is resin-molded, it is possible to prevent the breakage of the lead wire and the peeling of the pattern due to shock or vibration, and to stabilize the quality.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the above.

FIG. 3 is an operation waveform diagram of the above.

FIG. 4 is a characteristic diagram showing a load current and brightness of a light emitting diode in the same as above.

FIG. 5 is a cross-sectional view of the above switch body.

FIG. 6 is a plan view showing a state in which the above cover is removed.

FIG. 7 is a perspective view of an essential part of the above.

FIG. 8 is a front view of the main part of the above.

FIG. 9 is an exploded perspective view showing a construction state of the above.

[Explanation of symbols]

1 rectifying block 2 display blocks 4 body 5 cover 13 Storage 14 Storage 21 handle 24 Display 42 Mold block

Claims (2)

[Claims] 1. A diode is connected in a bridge shape, a diode is connected between the midpoints of respective sides to form a rectification block, and a display block is formed in which a light emitting diode is connected between the input and output ends of the rectification block. The switch with an indicator light is characterized in that an opening / closing mechanism is installed in the storage part of the body of the switch body including a cover and a body, and a display block is installed in the storage part of the handle. 2. The switch with an indicator lamp according to claim 1, wherein the rectifying block is resin-molded.