JP2005061584A - Electromagnetic valve for space system with operation monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation monitoring device capable of accurately performing monitoring of operation of an electromagnetic valve for a space system having operating properties for a small controlling amount of a flow rate and quick response speed by means of a control system at low costs and in a simple structure. <P>SOLUTION: In the electromagnetic valve for a space system having an operation monitoring device monitoring operating conditions of the valves including opening and closing timing of the electromagnetic valve, the electromagnetic valve comprises; a step detecting sequential change of electric current electrified into an electromagnetic coil; and a step detecting the beginning of opening of the electromagnetic valve at the basis of changed timing of an electric current change rate showing sequential change of electric current from a positive side to a negative side and detecting completion of opening of the electromagnetic valve when the electric current changing line becomes a first bottom after completing its changed timing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is applied to an electromagnetic valve that opens and closes a propulsion fuel passage of a space device including an artificial satellite, and is provided with an operation monitoring device that detects and monitors the operation state of the valve including the opening and closing timing of the valve. Regarding the valve.

  As a means for detecting and monitoring the operating state of a solenoid valve that is used for various control valves, flow control valves, etc. and requires high precision operation, conventionally, a laser beam has been applied to the valve body motion part of the solenoid valve. As a simple monitoring means, a monitoring means using a laser beam displacement meter for detecting the displacement of the body movement part, a means for monitoring while viewing an oscillograph waveform detected by an ammeter, and the like are used.

  As a means for detecting and monitoring the operation of a solenoid valve for controlling fuel injection timing in an internal combustion engine, the invention of Patent Document 1 (Japanese Patent Laid-Open No. 10-122416) has been proposed. In such an invention, the fail-safe signal generation unit of the load current processing unit generates a fail-safe signal based on the drive current, and the fail-safe signal generation unit is appropriately configured to cut off the drive current with respect to the end of the fuel injection signal. Whether the fail-safe signal is active or inactive is determined based on whether or not, and the electronic control unit is configured to diagnose the suitability of the drive current based on the inverted edge of the fail-safe signal.

JP-A-10-122416 (Abstract and FIG. 1)

An electromagnetic valve that opens and closes a propulsion fuel passage of a space device such as an artificial satellite has a characteristic that the valve lift is small and the flow rate control amount is small, but the response speed is extremely large.
However, in the monitoring means using the laser light displacement meter and the monitoring means using the oscillograph, since it is basically a visual detection, the operation state of the electromagnetic valve cannot be detected quantitatively. It cannot be applied to a solenoid valve for space equipment that has a low accuracy in detecting the operating state of the solenoid valve, a small flow rate control amount, and a very high response speed.
Further, in the invention of Patent Document 1, the operation of the fuel injection timing control solenoid valve can be detected with high accuracy, but the solenoid valve operation control system is complicated, large and costly.
And so on.

  In view of the problems of the prior art, the present invention enables high-accuracy monitoring of the operation of a solenoid valve for space equipment having a small flow rate control amount and a large response speed with a simple configuration and a low-cost control system. It aims at providing the operation monitoring device which can be enforced in.

  In order to solve such a problem, the present invention as claimed in claim 1 detects the operation state of the valve including the opening / closing timing of the valve that is opened / closed by the relationship between the energization / interruption of the electromagnetic coil and the spring force of the valve spring. The space valve solenoid valve having an operation monitoring device that monitors the current is provided with a current detector that detects a time change of the current supplied to the electromagnetic coil, and calculates a current change rate representing the time change of the current. Means for calculating a change timing when the current change rate changes from positive to negative in a current state equal to or greater than the spring force equivalent current, and detecting the start of opening of the electromagnetic valve based on the change timing and the current change line An operation monitoring device comprising: a processing device having means for detecting the end of opening of the solenoid valve according to a time when the first valley is reached after the change time; To propose a solenoid valve for space equipment.

  In addition to claim 1, preferably, as in claim 2, the processing device includes means for detecting the valve displacement of the electromagnetic valve by integrating the current change rate to give a constant gain. Is good.

  According to this invention, the change time when the current change rate calculated based on the detected value of the time change of the current supplied to the electromagnetic coil turns from positive to negative becomes the opening of the solenoid valve, and the current change line becomes the change time. The time when the first valley later, that is, the time when the rate of change in the previous period became a negative peak after the time of the change was found by experiments and simulations, and based on such knowledge, The opening start time of the solenoid valve and the opening end time when the solenoid valve reaches the maximum opening are detected.

Therefore, according to this invention, since the time change of the current is detected and the time change waveform is analyzed, the opening start time and the opening end time of the solenoid valve can be detected minutely and quantitatively, so that the flow rate control amount is small and the response. It is possible to accurately monitor the operation of the electromagnetic valve for space equipment, which is extremely fast.
In addition, a complicated control system that only analyzes the time-varying waveform of the current detected by the current detector is not required, and the above-described accurate monitoring can be performed with an extremely simple and low-cost structure and means. It can be performed.

In addition to claim 1, preferably, as in claim 3, a capacitor is connected to an energization circuit to the electromagnetic coil of the electromagnetic valve.
With this configuration, by connecting the capacitor to the energization circuit for the electromagnetic coil, it is avoided that the current to the electromagnetic valve is cut off stepwise, and the occurrence of an impact due to the sudden closing of the electromagnetic valve is avoided. Can be prevented.

As described above, according to the present invention, since the time change of current is detected and the time change waveform is analyzed, the opening start time and the opening end time of the solenoid valve can be detected minutely and quantitatively. It is possible to accurately monitor the operation of the electromagnetic valve for space equipment with a small response speed and extremely high response speed.
In addition, a complicated control system that only analyzes the time-varying waveform of the current detected by the current detector is not required, and the above-described accurate monitoring can be performed with an extremely simple and low-cost structure and means. It can be performed.

  According to the third aspect of the present invention, by connecting a capacitor to the energization circuit for the electromagnetic coil, it is avoided that the current to the electromagnetic valve is stepped off and the electromagnetic valve is suddenly closed. It is possible to prevent the occurrence of impact due to.

  Hereinafter, the present invention will be described in detail using embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this example are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.

  FIG. 1 is an overall configuration diagram of an operation monitoring apparatus for an electromagnetic valve for space equipment according to an embodiment of the present invention, and FIG. 2 is a control block diagram of the operation monitoring apparatus for the electromagnetic valve. FIG. 3 is a diagram showing the time variation of the solenoid valve current and solenoid valve operation in the above embodiment. FIG. 4 is a partial configuration diagram showing another example of the operation monitoring apparatus.

  In FIG. 1, 100 is a solenoid valve for space equipment, 1 is a valve body of the solenoid valve 100, 3a is a valve seat fixed to the valve body 1, 3 is a valve body, 4 is a working fluid inlet, A working fluid outlet having a micro passage area drilled in the valve seat 3a, 6 is a valve spring installed between the valve body 3 and the valve body 1, and 2 is an electromagnetic coil for driving the valve body 3. Reference numeral 10 denotes a displacement sensor for detecting the displacement of the valve body 3, but the displacement sensor 10 and the auxiliary rod 010 connected thereto may be omitted.

In the electromagnetic valve 100, when the electromagnetic coil 2 is energized, the valve body 3 is lifted to the right in the figure against the spring force of the valve spring 6 by the electromagnetic force generated in the electromagnetic coil 2, and the working fluid The inlet 4 side and the working fluid outlet 5 communicate with each other, and a small amount of the working fluid introduced into the working fluid inlet 4 is delivered from the working fluid outlet 5 having a small passage area.
When the energization of the electromagnetic coil 2 is interrupted, the valve body 3 is seated on the valve seat by the spring force of the valve spring 6 and the working fluid outlet 5 is closed.

In the operation monitoring device for the electromagnetic valve 100 shown in FIG. 1, reference numeral 17 denotes a power source, which connects and disconnects a switch 19 provided in an electric circuit 34 that connects the power source 17 and the electromagnetic coil 2 of the electromagnetic valve 100. Thus, the electromagnetic coil 2 is energized and cut off.
Reference numeral 14 denotes a current detector that detects a time change of the current flowing through the electric circuit 34 and is supplied to the coil 2, 15 is a low-pass filter, 16 is an A / D converter, 20 is a processing device, and 13 is a display device. is there.

  In such an operation monitoring device, the time change (current waveform) B (see FIG. 3) of the current to the coil 2 detected by the current detector 14 is removed from the high frequency noise by the low-pass filter 15 and A / D converted. The digital signal is converted into a digital signal by the device 16 and input to the processing device 20. The processing device 20 performs processing as described later, and the result is displayed on the display device 13.

Next, the operation of the operation monitoring device for the electromagnetic valve 100 will be described based on the control block diagram of FIG. 2 and the time change diagram of FIG.
The detection signal of the time change of the current B input from the A / D converter 16 to the processing device 20 is compensated for a smooth time change as shown in FIG. The compensation by the phase compensation unit 21 may be performed before the A / D converter 16. In the following description, the case of digital computation and control will be described using the analog time change diagram of FIG.

The current B that has been phase-compensated by the phase compensator 21 is input to the differentiator 23. The differentiator 23 performs a differentiation operation to obtain a current increase rate (current change rate) C. The current increase rate C Is input to the gradient detector 27. In the gradient detector 27, the current increase rate C is changed from positive (increase) to negative (decrease) when the magnitude of the current B is equal to or larger than the current corresponding to the spring force of the spring 6, that is, the valve opening spring force. a change in the timing T ₄ to change the input to the detection unit 29 starts to open detected valve to.
Here, that the current change rate C change time T ₄ to turn from positive to negative matches the timing T _s starts to open the solenoid valve 100, have been obtained by experiments and simulations, it begins to open such data the valve detected This is set in the section 29.
The valve opening start detection unit 29 calculates the opening start time T _s of the electromagnetic valve 100 by associating the current change rate C change time T ₄ with the valve displacement A of the electromagnetic valve 100.

Meanwhile, the phase compensation unit 21 a current phase compensation is made in B is also input to the peak value detection unit 22, the first valley in the current B is after T ₄ the change in timing in the peak value detector 22 timing that is calculating the time T ₂ to the current change rate C becomes negative peak.
Here, that the current B matches the first period T ₂ becomes valley period end opening of the solenoid valve 100 T _e after T ₄ the change in timing, have been obtained by experiments and simulations, it takes data The valve opening end detection unit 28 is set.
In the detection unit 28 end opening said valve, the current B calculates a first and a valve displacement A timing becomes valley T ₂ and the electromagnetic valve 100 in correspondence period end opening of the solenoid valve 100 T _e.

  Further, the current increase rate (current change rate) C from the differentiator 23 is input to the inverting unit 24, subjected to sign conversion by the inverting unit 24, and further multiplied by a certain gain by the gain applying unit 25. Integration operation is performed by the integrator 26 and input to the valve displacement detector 30, and the valve displacement detector 30 calculates the displacement A of the valve body 6 of the electromagnetic valve 100.

In the electromagnetic valve 100 from the timing end opening of the solenoid valve 100 T _e and the valve displacement detecting unit 30 from the start timing of the electromagnetic valve 100 T _s, the valve opening end detector 28 from the detector 29 starts to open the valve An operation state signal of the electromagnetic valve 100 such as the displacement A of the valve body 6 is input to the display device 13.
Therefore, the solenoid valve 100 can be accurately monitored by the operation state signal of the solenoid valve 100 displayed on the display device 13.

In another example of the operation monitoring apparatus shown in FIG. 4, a capacitor 18 is connected to the energization circuit 34 to the coil 2 of the electromagnetic valve 100.
The capacitor 18 prevents the current to the solenoid valve 100 from being cut off stepwise when the solenoid valve 100 is closed, and can prevent the occurrence of an impact due to the sudden closure of the solenoid valve 100.
Other configurations are the same as those of the embodiment of FIG. 1, and the same members are denoted by the same reference numerals.

  According to the present invention, the monitoring of the operation of the electromagnetic valve for space equipment having an operation characteristic with a small flow rate control amount and a large response speed can be performed with high accuracy with a simple configuration and a low-cost control system. A monitoring device can be provided, and it is effective as an electromagnetic valve for opening and closing a propulsion fuel passage for space equipment such as an artificial satellite.

1 is an overall configuration diagram of an operation monitoring apparatus for a solenoid valve for space equipment according to an embodiment of the present invention. It is a control block diagram of the operation monitoring device of a solenoid valve concerning the example of the present invention. It is a control block diagram of the operation monitoring device of the solenoid valve. It is a diagram which shows the time change of the solenoid valve current in the said Example, and a solenoid valve action | operation. It is a partial block diagram which shows the other example of the said operation | movement monitoring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Space equipment solenoid valve 1 Valve case 2 Electromagnetic coil 3 Valve body 3a Valve seat 6 Valve spring 13 Display device 14 Current detector 15 Low pass filter 16 A / D converter 20 Processing device 17 Power supply 19 Switch 34 Electric circuit

Claims (3)

  In the electromagnetic valve for space equipment provided with an operation monitoring device that detects and monitors the operation state of the valve including the opening and closing timing of the valve that is opened and closed according to the relationship between energization and shutoff of the electromagnetic coil and the spring force of the valve spring, A current detector for detecting a time change of the current supplied to the electromagnetic coil, a means for calculating a current change rate representing the time change of the current, and the current change rate in a current state equal to or greater than the spring force equivalent current; Means for calculating the change time when the current changes from positive to negative and detecting the start of opening of the solenoid valve based on the change time, and opening of the solenoid valve according to the time when the current change line becomes the first valley after the change time. An electromagnetic valve for space equipment comprising an operation monitoring device comprising a processing device having means for detecting the end.   2. The space provided with the operation monitoring device according to claim 1, wherein the processing device includes means for integrating the current change rate to give a constant gain and detecting a valve displacement of the electromagnetic valve. Solenoid valve for equipment.   The electromagnetic valve for space equipment provided with the operation monitoring device according to claim 1, wherein a capacitor is connected to an energization circuit to an electromagnetic coil of the electromagnetic valve.

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