JPH0117738Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a control circuit for a latching solenoid valve.

Generally, a latching solenoid valve is constructed as shown in FIG. In the figure, reference numeral 1 denotes a movable iron core made of a ferromagnetic material, and a ball valve 1' for opening and closing a hole 2' in a valve seat 2 is provided at one end of the core. 3 is movable iron core 1
This is an adsorption iron core attached to the final end in the direction of movement, and a permanent magnet 4 that provides an adsorption force is connected to this core. 5 is a spring inserted between the suction core 3 and the movable core 1 so that they repel each other, and 6 is an electromagnetic coil wound around the movable core 1.

In the above-mentioned solenoid valve, by passing current through the electromagnetic coil 6 to generate a magnetic field in the same direction as the magnetization direction of the permanent magnet 4, the attracting iron core 3 and the movable iron core 1 are
When a suction force is generated between the movable iron core 1 and the movable iron core 1 to be moved against the spring 5, the movable iron core 1 is attracted to the suction iron core 3. This attraction is maintained even after the electromagnetic coil 6 is de-energized, and the hole 2' of the valve seat 2 continues to communicate with the primary port 7 and the secondary port 8.

Next, when a current is passed through the electromagnetic coil 6 in the opposite direction to that in the above case, the magnetic field generated at this time cancels out the attraction force of the permanent magnet 4, and the movable iron core 1 is brought into the state shown in the figure by the force of the spring 5. The valve is then returned to close.

As mentioned above, the latching solenoid valve requires only instantaneous current to flow through the electromagnetic coil when the valve is opened or closed, so it has the advantage that it consumes much less power than ordinary solenoid valves and does not generate electromagnetic noise.

However, the conventional control circuit for such a solenoid valve is
For example, as shown in Jikai No. 51-80024,
It was necessary to supply power from the power supply each time the valve was opened and closed.

This invention was made in view of the above points,
The purpose of this is to have a movable core equipped with a ball valve at one end that opens and closes a hole in the valve seat, a suction core attached to the final end of the movable core in the direction of movement, and a movable core that is connected to the suction core. a permanent magnet that applies an attraction force to the attraction iron core; a spring inserted between the movable iron core and the attraction iron core so that they repel each other; and an electromagnetic coil wound around the movable iron core. A unidirectional current is temporarily applied to the electromagnetic coil to generate an attractive force between the attracting iron core and the movable iron core, and the movable iron core is moved against the spring by the attractive force. , the movable iron core is held in its moved state by the attraction force of the attraction iron core by the permanent magnet, and a current is passed in the opposite direction to the electromagnetic coil to reduce the attraction force that the permanent magnet is applying to the attraction iron core. In a latching solenoid valve in which the movable iron core, which is held in a moving state, is returned to its original position by the spring, when the solenoid valve is operated in one direction of opening and closing, It is an object of the present invention to provide a control circuit for a latching solenoid valve that makes it possible to further reduce power consumption by eliminating the need for power supply.

The present invention, which was developed to achieve this purpose, allows the charging current of the capacitor to flow through the electromagnetic coil when the valve is operated in one direction, and passes only the discharging current of the capacitor through the electromagnetic coil when the valve is operated in the other direction. It was designed to flow to

Embodiments of the present invention will be described below with reference to FIGS. 2 to 6.

FIG. 2 shows an embodiment of the control circuit according to the present invention, in which 10 is an AC power supply, 11 is a rectifier diode, and 1 is a control circuit according to the present invention.
2 is the solenoid coil of the latching solenoid valve (6 in Figure 1).
), 13 is a capacitor, 14 is a switch for opening and closing the solenoid valve, and 15 is a resistor. As the switch 14, a single-pole double-throw switch or a thermoswitch with a back contact can be used.

The operation of the circuit shown in FIG. 2 will be explained below with reference also to FIG. Now, when the movable contact a of the switch 14 is switched to the fixed contact b as shown in the figure, the charging current from the AC power supply 10 to the capacitor 13 flows through the diode 11 and the electromagnetic coil 12, and the charging current flows between the capacitor 13 and the AC power supply 10. Current stops flowing when the potential between the If the electromagnetic coil 12 is made to generate a magnetic field in the same direction as the magnetization direction of the permanent magnet 4 depending on the current direction at this time, the movable iron core 1 will be instantly attracted to the adsorption iron core 3 by the above-mentioned current and will be attracted. Therefore, the valve seat 2 is opened. This state is maintained even if the current stops flowing as long as no other external force is applied.

Next, when the switch 14 is switched to the fixed contact c side, the discharge current from the capacitor 13 flows into the electromagnetic coil 12 through the resistor 15 in the opposite direction to the charging current, so the electromagnetic coil 12 is connected to the permanent magnet 4. It begins to generate a magnetic field in the opposite direction to the magnetic direction. Therefore, the attraction force by the permanent magnet 4 is canceled, and the attraction core 3 is no longer able to continue attracting the movable core 1 against the force of the spring 5, and the movable core 1 is separated from the attraction core 3 and the valve seat 2 Close.

By the way, if the resistor 15 is not provided and the capacitance of the capacitor 13 is small, the capacitor 1
As shown by A in FIG. 3, noticeable damped oscillations occur in the discharge current of No. 3. When such damped vibration occurs, a current in the opposite direction as shown by diagonal lines flows through the electromagnetic coil 12, and the movable core 1 is attracted to the adsorption core 3, causing the valve seat 2 to open again. There is. At this point, as shown in the figure, resistor 1
When 5 is inserted, the discharge characteristics of A change as shown by the broken line, and the damped oscillation disappears, so the above-mentioned problems are solved.

However, this resistor 15 is unnecessary when the capacitor 13 has a large capacity and its discharge characteristics follow the curves B and C shown in FIG.

Furthermore, depending on the electromagnetic valve, if the discharge current to the electromagnetic coil 12 changes rapidly, the movable iron core 1 may not be able to follow it. In such a case, as shown in FIG. 4, by inserting an additional coil 12' into the discharge current path and increasing the discharge time constant of the capacitor 13, the broken line curve in FIG. As a result, the above-mentioned problems are resolved.

In short, in order to make the attenuation waveform of the discharge current of the capacitor 13 appropriate, it is necessary to
It is necessary to appropriately select the capacitance, discharge path resistance, and inductance values.

In the embodiment described above, the DC power supply that supplies the charging current to the capacitor 13 is composed of the AC power supply 10 and the diode 11 that performs half-wave rectification of the current AC. Therefore, when the half-wave rectified waveform disappears, a back electromotive force is generated in the electromagnetic coil 12, and a surge current begins to flow in the electromagnetic coil 12. However, this problem can be solved by connecting a diode 16 as shown by broken lines in FIGS. 2 and 4, or by using a full-wave rectified DC power source.

FIG. 5 shows an example in which the diode 11, capacitor 13, and resistor 15 in the control circuit described above are connected in advance to the electromagnetic coil 12 of the latching electromagnetic valve and assembled into the latching electromagnetic valve body as shown in FIG. show. By doing so, it is only necessary to connect the switch 14 and the AC power supply 10, as shown by the broken line in FIG. 6, and subsequent assembly work becomes easier.

As described above, the present invention includes a movable core provided with a ball valve at one end for opening and closing a hole in a valve seat, a suction core attached to the final end in the direction of movement of the movable core, and a suction core connected to the suction core. a permanent magnet that is provided and applies an attractive force to the attracting iron core; a spring inserted between the movable iron core and the attracting iron core so that they repel each other; and an electromagnetic coil wound around the movable iron core. A unidirectional current is temporarily passed through the electromagnetic coil to generate an attractive force between the attracting iron core and the movable iron core, and the movable iron core is moved against the spring by the attractive force. The movable iron core is held in the moved state by the attraction force of the attraction iron core by the permanent magnet, and a current is passed in the opposite direction to the electromagnetic coil to generate an attraction force that the permanent magnet is applying to the attraction iron core. In the latching solenoid valve, the movable iron core, which is held in a moving state, is returned to its original position by the spring, and the charging current from the power supply to the capacitor is canceled out by the electromagnetic valve only when the switch is in the first state. When the switch is in the second state, only the discharge current from the capacitor is passed through the resistor in the opposite direction to the electromagnetic coil to control the opening and closing of the latching electromagnetic valve.

For this reason, the structure of the latching solenoid valve is not only energy-saving, but also reduces power consumption by half compared to conventional valves that supply power from the power supply each time the valve is opened and closed. In addition to being suitable for energy saving and extremely economically advantageous, since the discharge current of the capacitor is discharged through a resistor, vibrations in the closed circuit are suppressed and valve switching is performed reliably. It will be done.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a general latching solenoid valve, FIG. 2 is a circuit diagram showing an example of a control circuit according to the present invention, FIG. 3 is a graph for explaining the circuit according to the present invention, and FIG. The figure is a circuit diagram showing another example of the circuit of the present invention, Figure 5 is a sectional view of a latching solenoid valve in which a part of the circuit of Figure 2 is assembled, and Figure 6 is about the latching solenoid valve of Figure 5. FIG. 10... AC power supply, 11... Rectifier diode,
12... Solenoid coil of latching solenoid valve, 13...
...Capacitor, 14...Switch.

Claims (1)

[Scope of Claim for Utility Model Registration] A movable core provided with a ball valve for opening and closing a hole in a valve seat at one end, a suction core attached to the final end in the direction of motion of the movable core, and a suction core connected to the suction core. a permanent magnet that is provided and applies an attractive force to the attracting iron core; a spring inserted between the movable iron core and the attracting iron core so that they repel each other; and an electromagnetic coil wound around the movable iron core. A unidirectional current is temporarily passed through the electromagnetic coil to generate an attractive force between the attracting iron core and the movable iron core, and the movable iron core is moved against the spring by the attractive force. The movable iron core is held in the moved state by the attraction force of the attraction iron core by the permanent magnet, and a current is passed in the opposite direction to the electromagnetic coil to generate an attraction force that the permanent magnet is applying to the attraction iron core. In the latching solenoid valve, the movable iron core, which is held in a moving state, is returned to its original position by the spring. The electromagnetic coil of the latching electromagnetic valve is connected to a DC power source via the capacitor in a first state of the switch, and a closed circuit of the capacitor, the resistor, and the electromagnetic coil is connected in a second state of the switch. A control circuit characterized in that it is configured to form.