JPH04239815A - Contactless on/off switch - Google Patents

Abstract

PURPOSE:To attain on/off of a large power contactlessly and to make the power consumption zero in the off-state by combining a magnetic proximity switch, a latching relay and an electronic circuit. CONSTITUTION:With a DC power supply 2 set inbetween, a magnetic proximity switch 1 and a latching relay 3 are arranged, and when a magnetic signal is given to the magnetic proximity switch 1 with a load 4 turned off, a timer B is reset with a differentiating output from a differentiating circuit comprising a capacitor 9 and a resistor 10, a signal from the magnetic proximity switch 1 activates the latching relay, timers A12, B7 restores to the off-state after lapse of a time to be in the standby state, and when a magnetic signal is given to the magnetic proximity switch 1 with the latching relay 3 activated, the differentiating circuit is not active and an output of a one-shot monostable multivibrator circuit 8 deenergizes the latching relay.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a non-contact device that is used in electrical devices and electronic devices, and is configured to turn on and off a power supply circuit in a non-contact manner by combining a magnetic proximity switch and an electronic circuit, and consumes zero power when turned off. Concerning on-off switches.

0002

[Prior Art] Conventional non-contact on/off switches that turn on and off circuits without contact include proximity switches that use magnetism, ultrasonic waves, and light; however, proximity switches that use ultrasonic waves and light drive sensors. Therefore, power is constantly consumed, and magnetic proximity switches that combine a permanent magnet and reed switch do not consume power, but the permanent magnet must be moved mechanically to turn the reed switch on and off. There was a problem.

0003

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention combines a magnetic proximity switch, a latching relay that turns on and off the main circuit, and an electronic circuit to transmit a magnetic signal to the magnetic proximity switch. This is a non-contact on/off switch configured to turn on the latching relay of the main circuit by applying a magnetic signal to the magnetic proximity switch, and turn off the main circuit by applying the next magnetic signal to the magnetic proximity switch. The purpose of the present invention is to provide a non-contact on/off switch that does not cause power generation, and that the power for turning on and off the main circuit is determined by the contact capacity of the built-in latching relay, and that it can be turned on and off even with a large amount of power.

0004

[Means for solving the problem] An on-off contact is inserted in parallel with a DC power source such as a battery, and in series with a circuit on the positive potential side and a circuit on the negative potential side, and an on-drive that turns on the parallel contacts. A latching relay is provided with a coil A and an off-driving coil B that turns off the contact, and the latching relay is connected between a load and a DC power source, while a magnetic proximity switch is connected in series to the positive potential side of the DC power source. The photocoupler The light receiving side of is connected to the input side of timer B, which has a capacitor connected in series to the input side, and the output of timer B triggers a one-shot multivibrator, and the output of the one-shot multivibrator is connected to the off-drive coil B of the latching relay. It is connected to the. The reset side of timer B is connected to the output of timer A through a gate circuit from the positive potential side of the CR differentiating circuit consisting of a capacitor and a resistor to which the load voltage is applied. It is configured to be in a non-operating state when a voltage is applied to the switch, making it a non-contact on/off switch.

That is, the present invention comprises a DC power supply 2, a magnetic proximity switch 1, an on-drive coil A3a and an off-drive coil B3b, a latching relay 3 for turning on/off power to a load 4, a photocoupler 5, The output of the light receiving element 5b of the photocoupler is passed through the capacitor 6, timer B7, and one-shot multivibrator 8 to the latching relay 3.
The voltage across the resistor 10 of a differentiator circuit consisting of a capacitor 9 and a resistor 10 connected to the off-drive coil B3b and connected in series to the load voltage 13 is applied to the gate circuit 11 and the timer A1.
A non-contact on/off switch configured to be connected to the reset input of timer B7 through 2, and when the latching relay 3 is off, it applies a magnetic signal to the magnetic proximity switch 1, turns on the magnetic proximity switch, and turns on the latching relay. Coil A3a is driven, contact 3c of the latching relay is turned on to supply voltage to the load, and when the load voltage rises, timer B is reset by the differential voltage of capacitor 9 and resistor 10 of the differentiating circuit. The operation is deactivated, and timer A and timer B return to the off state after a certain period of time.
When the latching relay is kept on and a magnetic signal is then applied to the magnetic proximity sensor, the differential circuit made up of the capacitor 9 and the resistor 10 is inactive, so the output of the magnetic proximity switch is output via the photocoupler 5 and capacitor 6. The non-contact device is characterized in that a timer B is activated, and a one-shot multivibrator triggered when the output of the timer B drives the off drive coil B of the latching relay to turn off the contact 3c of the latching relay. It is a contact on/off switch.

[0006]

[Operation] When the latching relay is in the OFF state and a magnetic signal is applied to the magnetic proximity switch, current flows through the ON drive coil A of the latching relay, turning the latching relay into the ON state and supplying power to the load. Supplies voltage to the electronic circuitry that makes up the contact on-off switch. At this time, coil B, which turns off the latching relay contact, is reset by timer A triggered by the differential output of the capacitor and resistor when the load power supply rises, and is suppressed to a non-operating state. No current flows. Once the on-drive coil A of the latching relay is turned on, it remains on even if there is no input from the magnetic proximity sensor. Timer A and timer B turn off after a few seconds, but the latching relay therefore connects the on state and continues to supply power to the load. Next, when a magnetic signal is input to the magnetic proximity switch again, the capacitor of the CR differential circuit on the input side of timer A is fully charged because the load voltage is on.
No differential output voltage is generated in the CR differentiation circuit, and therefore timer A does not operate. At this time, the output of the magnetic proximity switch passes through the photocoupler and triggers the input of timer B, and the output of timer B triggers the one-shot multivibrator, which drives off drive coil B that turns off the contact of the latching relay. Turn off and disconnect the load circuit. Timer A and timer B are turned off after several seconds of operation and return to a standby state.

[0007]

[Embodiment] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block circuit diagram of a non-contact on/off switch according to the present invention. FIG. 2 is a timing chart of the operation of the main circuits of the non-contact on/off switch according to the present invention.

In FIG. 1, one of the contacts of the magnetic proximity switch 1 is connected to the positive electrode of a DC power source (a battery is shown in the embodiment) 2, and the other contact of the magnetic proximity switch 1 is connected to the latching relay 3. It is connected to the on-drive coil A3a, and supplies current to the on-drive coil A3a when the magnetic proximity switch is on when the power source of the load 4 is off. Both positive and negative poles of the DC power supply 2 are connected to a contact 3c of a latching relay 3 that turns on and off power from the DC power supply 2 to the load 4. A voltage is connected and supplied to the light emitting element 5a of the photocoupler 5 via the on contact of the proximity switch from the DC power supply connected to the on drive coil A3a of the latching relay of the contact of the magnetic proximity switch 1, and the light emitting element 5a is a light receiving element. The output of the light receiving element 5b is connected to the input side of the timer B7 via the differential capacitor 6, and the output of the timer B7 drives the one-shot multivibrator 8; The output supplies an off-drive current to the off-drive coil B3b of the latching relay 3. Also, when the magnetic proximity switch 1 is turned on, the latching relay 3 is turned on at the input of the reset terminal R of the timer B7, and when power is supplied to the load 4, the load voltage 13 on the load side is connected to the capacitor 9 of the CR differential circuit. When voltage is supplied to the resistor 10, a differential voltage is generated across the resistor 10 due to the capacitor and the resistor, and when the differential voltage exceeds the gate circuit that determines the value of the operating voltage, it drives timer A and the timer output. is input to the reset side of the timer B.

The operation of each circuit constituting the non-contact on/off switch of the present invention shown in FIG. 1 will be explained with reference to the time chart shown in FIG. When the latching relay 3 in Fig. 1 is in the off state and sends a magnetic signal to the magnetic proximity switch 1, Fig. 2
Several pulse signals A are emitted by chattering from the magnetic proximity switch shown in FIG. At this time, a drive current is supplied from the DC power supply 2 to the on-drive coil A3a of the latching relay 3 through the magnetic proximity switch 1, turning on the contact 3c and supplying power to the load. At the same time, a voltage is applied from the DC power supply through the magnetic proximity switch 1 to the light emitting element 5a of the photocoupler 5 and the CR differential circuit including the capacitor 9 and the resistor 10. The output of the light receiving element 5b receiving the signal from the light emitting element 5a of the photocoupler 5 drives the timer B via the capacitor 6. A differential voltage is generated at both ends, and the differential voltage exceeds the gate voltage of the gate circuit 11 and drives the timer A12, and the output of the timer A12 is the output of the timer B7.
It is input to the reset side R of. Therefore, when the latching relay 3 is on and a load voltage is supplied to the load, when a positive voltage is applied from zero potential to the CR differential circuit consisting of the capacitor 9 and the resistor 10, the differential voltage across the resistor 10 is the same as that of the gate circuit 11. The threshold value is exceeded and timer A12 is driven, but during the time delay caused by capacitor 6 on the input side of timer B7, the output of timer A12 is input to the reset side of timer B, turning off timer B7, and the one-shot multi Turn off the output of vibrator 8, turn off drive coil B
The drive current to 3b is suppressed. After the timers A and B are activated, in this embodiment, they return to the off state after 3 to 5 seconds have elapsed. The latching relay 3 is turned on and remains on unless a magnetic signal from the next magnetic proximity switch is input.

Next, when a magnetic signal is sent to the magnetic proximity switch, the magnetic proximity switch 1 emits the signal shown in B in FIG.
7. Activate the one-shot multivibrator 8 and apply current to the off-drive coil B3b, contact 3 of the latching relay.
Turn c off. At this time, the reset input of timer B is applied to the differentiator circuit consisting of capacitor 9 and resistor 10, since the load voltage is applied to it, and no differential output voltage is generated across resistor 10. The reset input becomes zero. Therefore, the signal from the magnetic proximity switch operates the one-shot multivibrator 8 at the falling edge of the photocoupler 5, timer B7, and timer B7, and flows the off-drive current to the off-drive coil B3b of the latching relay 3 to turn off the latching relay 3. . That is, when the latching relay 3 is in the on state, the load voltage is always applied to the differentiating circuit composed of the capacitor 9 and the resistor 10, so the timer B7 is not reset by the timer A12, and therefore the load 4 The latching relay will turn off when applying a magnetic signal to the magnetic proximity switch only when the DC power supply is in the on state.

Since the non-contact on/off switch constructed as described above has a circuit structure in which the electronic circuit is operated by the load voltage, the power consumption of the non-contact on/off switch of the present invention becomes zero when the load voltage is off. Furthermore, a magnetic field created by passing a current through a coil installed close to the magnetic proximity switch is sufficient as the magnetic signal sent to the magnetic proximity switch, and the non-contact on/off switch of the present invention moves when using the magnetic field generated by the coil current. There are no structures present and the magnetic proximity switch can be turned on and off without moving the permanent magnet. On the other hand, when it is possible to have a movable structure, a structure in which the permanent magnets are placed close to each other may be used.

Although the embodiment of the present invention has been described as a non-contact on/off switch that uses a magnetic proximity switch and consumes zero power when in the off state, it is useful for devices that consume only a small amount of power in the off state. Naturally, a non-contact on/off switch similar to the present invention can be constructed using an optical sensor, an ultrasonic sensor, or the like as a proximity sensor.

[0013]

[Effects of the invention] A magnetic proximity switch that receives magnetic signals without contact, a latching relay that supplies power to a load, and 2
The non-contact on/off switch of the present invention, which combines a timer, a one-shot multivibrator, a differentiating circuit, and a time delay circuit, can be used as a power switch for a battery-powered device, for example, in a sealed container. It can be driven from outside the container, and its power consumption is zero when the power is off, so it can be applied to equipment used underwater and electrical and electronic equipment in environments where explosive gases exist. Therefore, the present invention provides a non-contact on/off switch of great industrial value.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram of a non-contact on-off switch according to the present invention.

FIG. 2 is a timing chart showing the operation of the main circuit of the non-contact on/off switch according to the present invention.

[Explanation of symbols] 1 Magnetic proximity switch 2 DC power supply 3 Latching relay 3a On-drive coil A 3b Off-drive coil B 3c Contact 4 Load 5 Photocoupler (PC) 5a Light-emitting element 5b Light-receiving element 6 Capacitor 7 Timer B 8 One-shot multi vibrator 9
Capacitor 10 Resistor 11 Gate circuit 12 Timer A 13 Load voltage

Claims (1)

[Claims] [Claim 1] A magnetic proximity switch (1), an on-drive coil A (3a) and an off-drive coil B (3b) are provided between a DC power source (2) and turn on/off power to a load (4). The output of the latching relay (3), photocoupler (5), and photocoupler light receiving element (5b) is connected to the capacitor (6).
), a capacitor (9) connected to the off-drive coil B (3b) of the latching relay (3) through the timer B (7) and the one-shot multivibrator (8), and connected in series to the load voltage (13). The voltage across the resistor (10) of the differential circuit consisting of the gate circuit (11) and the resistor (10)
) and connected to the reset input of timer B (7) via timer A (12). Magnetic proximity switch (1)
is turned on to drive the on-drive coil A (3a) of the latching relay (3), and the contact point (3c) of the latching relay is turned on.
is turned on to supply voltage to the load (4), and when the load voltage rises, the timer B (7) is reset by the differential voltage of the capacitor (9) and resistor (10) of the differentiating circuit. ) is deactivated, timer A (12) and timer B (7) return to the off state after a certain period of time, the latching relay (3) maintains the on state, and then the magnetic signal is sent to the magnetic proximity sensor ( 1) When the voltage is applied to the capacitor (
9) The differential circuit by the resistor (10) is inactive, so the output of the magnetic proximity switch (1) operates the timer B (7) via the photocoupler (5) and the capacitor (6). ) The one-shot multivibrator (8) triggered at the falling edge of the output of the latching relay (3
A non-contact on/off switch characterized in that it is configured to drive the off drive coil B (3b) of ) and turn off the latching relay (3).