JPH0792163B2 - Solenoid valve drive - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an electromagnetic valve drive device, and more particularly to improvement of electromagnetic coil drive control.

[Prior Art] As a conventional solenoid valve drive device, for example, Japanese Patent Laid-Open No. 61-41085
There is one disclosed in the publication. According to this drive device, a large drive current flows in the initial stage of energization of the electromagnetic coil, and feedback control of the drive current is performed so that the minimum holding current level of the solenoid valve is reached at or after the completion of switching of the solenoid valve.

FIG. 2 shows a schematic configuration of such a conventional device. In this figure, a control circuit 92 is connected to the electromagnetic coil 90 of an electromagnetic valve (not shown), and the electric power of the drive power supply 94 is controlled by the control circuit 92 and added to the electromagnetic coil 90. It's

The control circuit 92 includes an exciting circuit 92A that supplies a large current when the electromagnetic coil 90 is initially energized, a holding exciting circuit 92B that supplies a minimum current required to hold the electromagnetic valve, and an exciting circuit 92A that supplies the electromagnetic coil 90 with the electromagnetic coil 90. The determination circuit 92C for determining that the current value to be reached has become the current required for switching the solenoid valve is included.

Next, the operation of the above-described conventional example will be described. First, a large current is supplied to the electromagnetic coil 90 by the exciting circuit 92A. At this time, the drive current flowing through the electromagnetic coil 90 gradually increases, but eventually becomes a current value required for switching the electromagnetic valve.

When this is judged by the judgment circuit 92C, the holding excitation circuit 9
2B starts operation. That is, the electromagnetic coil 90 is supplied with the minimum holding current required to hold the state of the electromagnetic valve.

[Problems to be Solved by the Invention] However, in the conventional device as described above, a large amount of electric power is applied to the electromagnetic coil at the start of energization in order to improve the response, which causes heat generation and shortens the service life. There is an inconvenience of causing a decrease.

The present invention has been made in view of the above points, and an object thereof is to provide a solenoid valve drive device capable of improving responsiveness, reducing energy consumption, and prolonging the life of a solenoid valve. It is a thing.

[Means and Actions for Solving Problems] The present invention includes an on-offset means and an on-slope shaping means for raising the driving force of an electromagnetic coil at the start of valve driving, and further for driving for maintaining the opening of the electromagnetic valve. A holding offset setting means for setting a force, and an off-slope shaping means when the driving force is cut off are provided.

According to the present invention, the driving voltage is raised by the on-offset means and applied to the electromagnetic coil, the holding current is controlled by the holding offset setting means, and the holding current is shut off by the off-slope shaping means. And it is driven smoothly.

Embodiments Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The same components as those in the conventional example described above will be denoted by the same reference numerals.

FIG. 1 shows an embodiment of the solenoid valve drive system according to the present invention, in which the voltage is controlled and the on-offset means is formed to instantly raise the voltage at the start of valve drive. There is. In this figure, the control circuit 10 is connected to the electromagnetic coil 90 of the solenoid valve (not shown), so that the DC output of the driving power supply 30 is waveform-shaped by the control circuit 10 and input to the electromagnetic coil 90. Has become.

The driving power source 30 is an AC power source (for example, commercial 50 or 60HZ, 10
DC power is obtained from (using 0V), and is configured by using a diode, a thyristor, etc., and its output voltage value is changed by the variable resistor 32.

Next, the control circuit 10 has a plurality of circuit parts for waveform shaping. First, the external command for driving the solenoid valve is input by the command input unit 12, and based on this, the waveform shaping and its output are performed.

Next, the on-offset shaping unit 14 as on-offset means
As shown in FIG. 3 (A), is for setting the on-offset voltage VA at the time of rising of the output voltage, and the value of VA can be set by the variable resistor 14R.

Next, the on-slope shaping unit 16 which is the on-slope shaping means
Is for setting the slope SA after the output voltage rises, and the degree of the slope can be set by the variable resistor 16R.

Next, the holding offset shaping section 18 serving as holding offset setting means secures a current necessary to hold the state after the valve operation, and sets the holding offset voltage VB. The value of this VB can be set by the variable resistor 18R.

Next, the off-slope shaping unit 20 as the off-slope shaping means
Is for setting the off slope SB when the output power supply falls, and the degree of the slope can be set by the variable resistor 20R.

The maximum value VC of the output voltage can be set by the variable resistor 32 of the drive voltage 30.

Next, the slope time T at the time of turning on and off can be set by the slope time setting unit 22, and its length can be set by the variable resistor 22R. Since this slope time T corresponds to the time required to move the valve associated with opening and closing, it is the same at the time of rising and at the time of falling, but may be set differently as necessary. Good.

Next, the overall operation of the above embodiment will be described with reference to the time chart of FIG.

First, when a command to drive the solenoid valve is issued from the outside to the command input unit 12, the control circuit responds to the DC output of the driving power supply 30.
Waveform shaping by 10 is performed.

First, the on-offset shaping unit 14 raises the voltage to a predetermined voltage VA. The value of VA is not so high that the solenoid (not shown) of the valve is completely attracted to the electromagnetic coil 90. Therefore, by the on-slope shaping unit 16,
The voltage is shaped so that it gradually increases from the on-offset voltage VA.

When the above voltage is applied to the electromagnetic coil 90, the third
As shown in FIGS. (B) and (C), the valve moves to be in the “open” state.

Next, when the time T set by the slope time setting unit 22 has elapsed, the holding offset shaping unit 18 reduces the voltage from VC to VB. In this way, the voltage is reduced to the holding offset voltage VB because a low coil drive current due to such a low voltage is sufficient to maintain the valve state, that is, the attraction force of the solenoid. This is because the flow causes an inconvenience such as causing unnecessary heat generation of the electromagnetic coil 90.

Next, after changing to the holding offset voltage VB, when the command input unit 12 is commanded to externally close the solenoid valve, the off-slope shaping unit 20 gradually changes the voltage according to the time set by the slope time setting unit 22. Is reduced (see FIG. 3 (A)). By this operation, the valve gradually moves (see (B) in the same figure) and becomes a closed state (see (C) in the same figure).

That is, as described above, before the command to close the valve, only the drive current necessary to maintain the valve open state flows in the electromagnetic coil 90 by the holding offset voltage VB. For this reason, when the valve closing command is issued and the voltage starts to drop even slightly, the valve cannot be maintained in the open state and quickly shifts to the closed state.

As described above, this embodiment has the following effects.

First of all, after the opening operation of the valve, the value of the drive current is set to the minimum reduction value necessary for maintaining the state, so unnecessary power consumption is reduced and the amount of heat generation is reduced.

Secondly, by setting the holding offset voltage close to the minimum necessary value for maintaining the valve open, the valve closing operation can be performed quickly and the response of the closing operation is also improved.

Thirdly, by opening and closing the valve by a voltage or current change that has been subjected to on-slope shaping or off-slope shaping, the shock given to the valve at the time of opening and closing is alleviated.

Next, a specific design example of the above embodiment will be described with reference to FIG.

FIG. 4 shows a design example of the embodiment shown in FIG. In this example, the control circuit 10 is designed by using a commercially available IC. An example of measurement of the output voltage waveform of this example is shown in FIG.

The on-offset means shown in FIG. 6 is formed so as to rise slightly before the start of valve drive.

More specifically, the voltage is first raised to VO just before the solenoid valve is driven, and then the voltage for moving the solenoid valve is applied when the solenoid valve is actually operated.

With this configuration, when the excitation timing of the electromagnetic coil 90 is known in advance, the voltage is raised by (VA-VO) slightly before the excitation, and then the voltage is gradually raised by the on-slope shaping unit 16. It will be formatted to do.

Therefore, compared with the embodiment shown in FIG. 1 to FIG. 5, the voltage to be raised is as low as (VA-VA), so that the response can be improved.

Further, the one shown in FIG. 7 is formed as an on-offset means so as to be continuously raised before the valve drive is started.

More specifically, the voltage of the electromagnetic coil 90 is always raised to VO, and then the voltage for moving the electromagnetic valve is applied when actually operating the electromagnetic valve.

If formed in this way, even when the excitation timing of the electromagnetic coil 90 is not known in advance, the voltage is raised by (VA-VO) just before the excitation, and then the on-slope shaping section 16 is used. It is shaped so that the voltage gradually rises.

Therefore, it can be excited at any time as in the embodiment shown in FIGS.
Compared to the embodiment shown in the figure, the voltage to be increased is (VA-V
O), which is low, so the response can be good.

Although a detailed design example is omitted, the solenoid valve drive device according to the present invention also achieves the same function and effect not by controlling the voltage but by changing the current value while keeping the voltage value constant. It is a thing.

Note that the present invention is not limited to the above-described embodiment, and the waveform shaping circuit may have various configurations, for example. If necessary, a protection circuit for overvoltage, overcurrent, noise, temperature change, etc. may be provided.

[Effects of the Invention] As described above, according to the present invention, since the electromagnetic valve drive device is capable of adjusting the holding offset voltage after the drive voltage for the electromagnetic coil is once raised, the response speed of the electromagnetic valve is improved. In addition, it is possible to extend the life of the valve due to the reduction in the amount of heat generated due to the reduction of unnecessary power consumption, and it is possible to perform the opening / closing operation with a shock when the valve is opened / closed. Therefore, there is an effect that the opening / closing control voltage or current according to the application of the solenoid valve can be easily adjusted and set to easily extend the life of the valve.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing an embodiment of the present invention, and FIG.
FIG. 4 is a circuit block showing a conventional example, FIG. 3 is a diagram showing the operation of the embodiment of FIG. 1, FIG. 4 is a circuit diagram showing a design example, and FIG. 5 is an output characteristic of the design example of FIG. FIG. 6 is a diagram showing the operation of another embodiment, and FIG. 7 is a diagram showing the operation of yet another embodiment. 10 …… Control circuit, 12 …… Command input section 14 …… On offset shaping section 16 …… On slope shaping section 18 …… Protection offset shaping section 20 …… Off slope shaping section 22 …… Slope time setting section 30 …… Drive power supply, 90 ... Electromagnetic coil

Claims (1)

[Claims] 1. A solenoid valve drive device for maintaining a valve open / closed state by applying a drive force having a value different from that at the time of driving, to a predetermined voltage or wave current value at the time of starting valve drive. On-off means for raising the value to the on-offset value, on-slope shaping means for determining the rate of increase from the on-offset value, and holding offset for adjusting and setting the voltage or current value after a predetermined time has elapsed after the start of valve drive An electromagnetic valve drive device comprising: setting means; and off-slope shaping means for setting a voltage or current drop rate when the power is shut off.