JPS5835327B2 - 2-wire non-contact micro switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-wire non-contact microswitch that controls the transmission and reception of light between a light emitter and a light receiver by operating a push button, etc., and performs a switching operation based on this control.

In conventional non-contact microswitches, light emitting elements,
Since the light-receiving element and the like were individually packaged, that is, large in shape, the overall structure of the device was also large, which was a bottleneck in achieving miniaturization.

In addition, since there are many wiring for each element and connections with external circuits (circuits that amplify the output of the light-receiving element, current-limiting resistors of the light-emitting element), etc., there are many steps, which increases costs and is complicated. Ta.

Further, the conventional non-contact microswitch is configured as a three-wire type.

This is at least 2 pieces for power supply 1. It has at least one terminal for signals, a total of three terminals, and the power supply is connected to the two terminals for power supply, and one of the terminals for signal and two terminals for power supply is connected. The idea is to connect a load between the two and apply a signal to the load to control on/off of the load.

However, in the case of a 3-wire system, the signal cable has 3 connections, which not only complicates the connection work, but also increases the possibility of mixing up the connection points, and furthermore, in the event of a failure, there are 3 connections in the signal cable. It is also troublesome in terms of maintenance, as each wire must be inspected to see if it is broken.

The present invention provides a 2-wire non-contact microswitch that is easy to downsize and assemble, thereby reducing manufacturing costs, and that eliminates the drawbacks of the 3-wire type described above by configuring it as a 2-wire type. The purpose is to provide.

An embodiment of the present invention will be described below.

First, its configuration will be explained along the manufacturing process.

First, as shown in FIG. 1, terminal pieces 11 to 14, locking pieces 15 and 16, and frame 10 are formed by punching out a metal plate.

Each of the terminal pieces 11 to 14 and the locking pieces 15, 16 are punched out so as to be connected to the frame 10, so that they cannot be separated.

Further, the locking piece 15 is provided with a hole 151, and the locking piece 16 is provided with a hole 151.
A groove 161 (see FIG. 5B) and a notch 162 are provided in the groove 161 (see FIG. 5B).

Next, as shown in FIG. 2, pellets 3 and 4 are fixed to the locking piece 16 and the terminal piece 13, respectively.

The pellet 3 is an IC pellet for forming a light receiving section including a light receiving element 30 (described later in FIG. 7B).

A light receiving section is formed by connecting the terminals of this IC pellet 3 to the terminal piece 11 (via the locking piece 16) and the terminal pieces 12 to 14.

Pellet 4 is a light emitting element pellet, and its terminal is terminal piece 1
3 and 14.

Next, as shown in FIG. 3, transparent resin members 21 and 22 containing the IC pellet 3 and the light emitting element pellet 4, respectively
is molded under low pressure, and then, as shown in FIG. 4, an opaque resin case 2 including the transparent resin members 21, 22, terminal pieces 11 to 14, and locking pieces 15, 16 is molded.

After doing this, the frame 10 is cut to separate the case 2 from the frame 10 as shown in FIG.

Then, the locking pieces 15 and 16 are further bent as shown in FIG.

Note that covers 5 (Fig. 7 A, B,
Claws 25 and 26 (see FIG. 5B) are provided, respectively, for locking the handles (see FIG. 5B).

Further, the convex portion 23 of the case 2 is provided with a stopper 24, which will be described later.

Next, a coil spring 6 and a light shielding plate 7 shown in FIG. 8 are attached to this case 2.

Figure 7 A, B. As shown in C, while locking the spring hook 62 of the coil spring 6 in the hole 71 of the light shielding plate 7, insert the other spring hook 61 into the hole 151 of the locking piece 15 (see FIG. 6).
to be locked.

Then, one end of the light shielding plate 7 is engaged with the groove 161 of the locking piece 16.

At this time, the light shielding plate 7 receives a counterclockwise torque from the coil spring 6 and is stopped by the stopper 24.

Then, the cover 5 with the push button 8 attached to the hole 51 is placed over the case 2.

This cover 5 is prevented from coming off by claws 25 and 26.

Moreover, this cover 5 is equipped with a reflective surface 50 on the inner wall,
When the case 2 is covered, the light beam projected from the light emitting element pellet 4 is just reflected by the reflecting surface 50 and enters the light receiving element 30 of the IC pellet 3.

The pellets 3 and 4 constitute a circuit section.

For example, as shown in FIG. 9, this circuit section 31 includes a photoelectric detection circuit 32, a constant voltage circuit 33 including a smoothing circuit, a 5CR34 which is an example of a switching element, and a constant voltage diode 35.
, a reverse current prevention diode 36, a current limiting resistor 37, and a rectifying bridge 38.

The photoelectric detection circuit 32 includes a light emitting element (pellet) 4, a light receiving element 30, an amplifier circuit 321, and a level detection circuit 322.

Next, the operation of the non-contact microswitch constructed in this way will be explained.

Figure 7A. When push button 8 is pressed at B and C,
The push button 8 is recessed and the coil spring 6 is deflected.

In addition, since the locking piece 16 is provided with a notch 162,
The spring 6 can be sufficiently bent.

Initially, when the deflection is small, the light shielding plate 7 is still subjected to counterclockwise torque by the spring 6, and is positioned upward while being stopped by the stopper 24.

At this time, the light shielding plate 7 blocks a portion of the light rays from the light emitting element pellet 4 and prevents the light rays from entering the light receiving element 30.

Therefore, in FIG. 9, the output of the photoelectric detection circuit 32 becomes "L", and the 5CR 34 is turned off.

As a result, the terminal strips 11 and 12 are turned off (strictly speaking, as will be described below, the current supplied to the photoelectric detection circuit 32 flows as a leakage current).

However, this is extremely small and can be considered off).

On the circuit section 31 side, a voltage as shown in FIG. 11A is generated at point A.

This voltage is dropped by the resistor 37, and a voltage as shown in FIG. 11B is generated at point B.

Therefore, sufficient current can be supplied to the photoelectric detection circuit 32 for operation.

In FIG. 7 A, B, and C, the pushbutton 8 becomes more and more immersed.
When the spring 6 is bent to a certain extent, the light shielding plate 7 is now subjected to a clockwise torque and is positioned downward by a snap action.

Then, part of the light rays that were blocked until now will be covered by cover 5.
The light is reflected by the anti-tree surface 50 and enters the light emitting element 30.

Therefore, in FIG. 9, the output of the photoelectric detection circuit 32 becomes "H" and the 5CR 34 is turned on.

As a result, the connection between the terminal pieces 11 and 12 is turned on, and power is supplied to the load.

On the other hand, on the circuit section 31 side, a voltage as shown in FIG. 12C is generated at point C.

This voltage is dropped by the forward drop voltage by the diode 36, and a voltage as shown in FIG. 12B is generated at point B.

Therefore, in this case as well, sufficient current is supplied to the photoelectric detection circuit 32 for operation.

In this way, the photoelectric detection circuit 32 operates by receiving power supply whether the 5CR34 is on or off.
This is to output a detection signal to be applied to the gate of 5CR34.

When the push button 8 is released, the coil spring 6 returns to its undeformed state by its own elastic force, and pushes the push button 8 back up to its original position.

Accordingly, the light shielding plate 7 also comes to be positioned upward by a snap action, and as a result, the connection between the terminal pieces 11 and 12 is turned off.

It goes without saying that the present invention is not limited to the above-mentioned embodiments. For example, as shown in FIG. Good too.

Further, as shown by the dotted line in FIG. 6, a convex portion 20 forming a reflective surface may be provided on the case 2 to serve as the reflective surface 50, or a reflective surface may be provided on the light shielding plate 7. The light beam is reflected by this reflective surface and enters the light receiving element 30, while when the push button 8 is depressed, the reflective surface is reflected by the light shielding plates 7, 7.
The light receiving element 30 may also be located below the light receiving element 30 so that no light enters the light receiving element 30.

In FIG. 13, parts corresponding to those in FIG. 7B are given corresponding numbers and their explanations are omitted.

Alternatively, the entire case may be made of transparent resin so that the case can be molded all at once.

In this case, cover the entire case with an opaque cover.

Furthermore, in the above embodiment, a so-called voltage division type two-wire switching circuit is adopted as the circuit configuration as shown in FIG. 9, but a phase division type two-wire switching circuit is used as shown in FIG. May be adopted.

That is, instead of the constant voltage diode 35 in FIG.
5CR40, a constant voltage diode 39, and a resistor 41 are provided.

In this case as well, 5CR is determined according to the output of the photoelectric detection circuit 32.
34 can be turned on and off to control the power supply to the load.

On the circuit section 31a side, when 5CR34 is off, the 15th
Voltages as shown in the figure are generated at points A and B, and current is supplied to the photoelectric detection circuit 32.

On the other hand, when 5CR34 is on, voltages as shown in FIG. 16 are generated at points B and C.

5C from the time when the anode potential of 5CR40 becomes zero
This is because the gate current does not flow and the 5CR40 is not triggered until R40 is turned off and the anode potential exceeds the Zener potential Vz of the voltage regulator diode 39.

Therefore, even in this case, sufficient current can be supplied to the photoelectric detection circuit 32.

As explained above, using actual cases, according to the present invention, the circuit section is divided into an IC on the light receiving side and the light emitting side, and both semiconductor pellets are embedded in the case. Therefore, miniaturization can be achieved.

Further, since the terminal pieces are made of plate-shaped members arranged on the same plane, they can be easily formed by punching or the like.

Furthermore, since the semiconductor pellets only have to be fixed to the terminal pieces and then wired, the fixing and wiring work is extremely easy.

In this way, assembly work becomes extremely simple and manufacturing costs can be reduced.

In addition, since the circuit section is composed of a photoelectric detection type two-wire switching circuit, the number of external terminals can be reduced by 11, making it more compact. It also becomes easier.

Furthermore, since there are two external terminal pieces and two external wires, even if a cable breaks, it is easy to confirm the failure and improve reliability.

[Brief Description of the Drawings] Figures 1 to 6 are diagrams explaining each process according to one embodiment of the present invention, and Figures A, B, and C are partially cross-sectional views of this embodiment. 8 is a perspective view showing the light shielding plate 7, FIG. 9 is a block diagram showing the circuit configuration, and FIG. 10 is the same as that shown in FIG. 9. Photoelectric detection circuit 3
2, FIG. 11 and FIG. 12 are waveform diagrams showing waveforms at each point in FIG. 9, FIG. 13 is a side view showing a modified example, and FIG. 14 is a block diagram showing another modified example. , 15th
The figure and FIG. 16 are waveform diagrams showing waveforms at each point in FIG. 14. 10... Frame, 11-14... Terminal piece, 15.16... Locking piece, 2...
Case, 21゜22...Transparent resin member, 3...
...IC pellet, 31.31a...Circuit part, 4...Light emitting element pellet, 5...
Cover 6... Coil spring, 7... Light shielding plate.

Claims (1)

[Claims] 1. Two plate-shaped terminal pieces arranged on the same plane and to which a power source and a load are to be connected in series, and a terminal piece connected to the two terminal pieces and connected between these terminal pieces. It has a switching element that performs switching, and is further connected to the two terminal pieces in parallel with the switching element, and receives power supply to drive the switching element when the switching element is turned on or off. A light-receiving semiconductor pellet having a light-receiving element and a light-receiving circuit that outputs a detection signal, and a light-emitting element that is connected to the two terminal pieces and emits light upon receiving power when the switching element is turned on or off. a transparent resin member molded including the light-receiving semiconductor pellet and the light-emitting semiconductor pellet, and a mold-molded opaque synthetic resin including the transparent resin member and the terminal piece. a case; a reflecting surface disposed opposite to the light-emitting semiconductor pellet and the light-receiving semiconductor pellet to reflect the light beam projected by the light-emitting element and make it enter the light-receiving element; and a reflecting surface attached to the case so as to control this reflection. A two-wire wireless device comprising: a movable piece; a cover fitted to the case so as to cover the reflective surface and the movable piece; and a push button attached to the cover to operate the movable piece. Contact micro switch. 2. The two-wire non-contact microswitch according to claim 1, wherein the movable piece is driven by a snap action. 3. The two-wire non-contact microswitch according to claim 1, wherein the movable piece is driven by a slow action. 4. The two-wire non-contact microswitch according to claim 2 or 3, wherein the reflective surface is provided on the movable piece. 5. The two-wire non-contact microswitch according to claim 2 or 3, wherein the reflective surface is provided on the inner surface of the cover. 6. The two-wire non-contact microswitch according to claim 2 or 3, wherein the reflective surface is provided to protrude from the case.