JPWO2006022408A1 - Motorized valve diagnostic method and diagnostic device - Google Patents

Abstract

Provided are a diagnosis method for a motor-operated valve capable of performing diagnosis of the motor-operated valve with high accuracy, and a diagnosis device suitable for carrying out the diagnosis method. In the motor-operated valve diagnosis method for diagnosing the driving force of the motor-operated valve having a spring cartridge that expands and contracts according to the reaction force acting in the axial direction of the worm in the valve body driving unit, The correlation between the driving force output signal from the valve element driving unit and the driving force obtained from the compression state of the spring cartridge in both closing operations is stored as a first correlation database, and the driving force input to the valve element driving unit The correlation between the signal and the driving force output signal is acquired, and the change state of the driving force transmission efficiency in the valve body driving unit is monitored based on the correlation, and the measurement is acquired by referring to the first correlation database The driving force corresponding to the yoke stress to be read is read, and a diagnosis relating to the driving force of the motor-operated valve is performed based on the driving force.

Description

  The present invention relates to a diagnostic method and a diagnostic apparatus suitable for carrying out the diagnostic method in the case of performing a diagnosis relating to the driving force of an electric valve.

The motor-operated valve is configured to open and close the valve body with a motor driving force, and its greatest features are that a large valve body driving force can be secured and that the opening and closing operation can be performed remotely. Because of these characteristics, for example, it is frequently used in large plants equipped with large-diameter pipes, pipes of nuclear power plants where manual operation is regulated, and the use is used as a valve for flow rate adjustment. It is often used as a valve for fully opening and closing the flow path in the pipe.
Such an electric valve includes a valve body that opens and closes a flow path in a pipe, a valve body drive unit that opens and closes the valve body in response to the rotational force of a worm that is rotationally driven by a motor, and the valve body drive A spring cartridge in which a disc spring that expands and contracts in accordance with the thrust generated in the worm is compressed with a specified compression force (the compression force at this time is referred to as “tension load”), The driving force obtained from the compressed state, that is, the torque of the motor-operated valve is applied to the valve body driving unit to open and close the valve body, while the motor is stopped when the compression amount of the spring cartridge reaches the regulation amount. This ensures a highly reliable valve function with the proper opening and closing force of the valve and prevents damage by avoiding excessive driving force.
On the other hand, in order to maintain the function of the motorized valve for a long period of time, not only the soundness of the function of the motorized valve itself is confirmed, but also the rotational force of the motorized part or the worm is applied to the valve body side. It is necessary to check the soundness of the transmitting valve body drive unit. The focus of diagnosis for this is, for example, whether or not the valve body is driven with an appropriate torque, whether or not an appropriate holding torque is ensured in the fully open / closed state of the valve body, and the required torque is applied. The setting of the torque switch that automatically stops the motor at the time when the motor is applied is appropriate, the degree of progress of the wear of the valve body drive unit, and the like. Among these diagnostic items, the torque [a physical quantity having a certain relationship with the compression force of the spring cartridge, that is, a torque obtained from the compression force of the spring cartridge, and torque = spring cartridge compression force × r ( r: obtained as ½ of the pitch circle diameter of the worm wheel (see FIGS. 1 and 2)) is based on the past example that many of the malfunctions of the motor-operated valve are caused by torque improperness. Is considered the most important. For this reason, various proposals have conventionally been made for methods for diagnosing motor-operated valves related to torque.
For example, as shown in Patent Document 1, a strain gauge is attached to a spring cartridge portion, and the compression force of the spring cartridge, that is, a torque value corresponding to the compression force of the spring cartridge is obtained by the strain gauge in the operating state of the electric valve. There is a so-called “built-in torque sensor method” in which a diagnosis regarding torque is performed based on the acquired torque.
Further, a method has been proposed in which a detection means related to torque is attached to the outer end side of the spring cartridge, and a motor-operated valve related to torque is diagnosed using this detection means during diagnosis work (see Patent Documents 2 and 3).
What is disclosed in Patent Document 2 is a so-called “torque sensor external method”, and a compression force detecting means for detecting a compression force applied to the spring cartridge on the outer end side of the spring cartridge, and the spring cartridge A moving amount detecting means for detecting the amount of compression, that is, the moving amount of the worm is attached. Then, with the motor operated, the correlation between the compression amount of the spring cartridge detected by the compression force detection means and the movement amount detection means and the corresponding compression force is acquired. Thereafter, the amount of compression is measured, and the compression force actually acting is obtained from the measured value with reference to the correlation. Further, the torque actually acting on the valve body drive unit by the worm is determined based on the compression force, and a diagnosis relating to the torque of the electric valve is performed based on the torque.
According to this method, the compression force can be detected only on one side of the open operation or the close operation of the motorized valve due to the structure of the compression force detecting means, but the operation direction of the motor operated valve is the open operation direction. Even if it is in the closing operation direction, the phenomenon that the spring cartridge is compressed is the same and there is no difference, so even the amount of compression of the spring cartridge is measured both in the opening operation and in the closing operation. If so, the compressive force on the other side can also be known. That is, if the amount of compression and the value obtained by converting the amount of compression into torque are acquired as data, if the amount of compression is measured both during the opening and closing of the motorized valve, the corresponding torque can be obtained. It is something you can know.
On the other hand, what is disclosed in Patent Document 3 is a so-called “spring compression method”, and a strain gauge and a position detection means are provided on the outer end of the spring cartridge (that is, the end on the opposite side of the spring cartridge). And the compression means is attached, and the disc spring of the spring cartridge is compressed from the outside by the compression means under the operation stop state of the motorized valve, and in this case, the compression force on the spring cartridge is applied by the strain gauge and the spring cartridge. Are acquired by the position detection means, respectively, and the relationship between the compression amount of the spring cartridge and the corresponding compression force is acquired. Next, the amount of compression is measured under the operating state of the motorized valve, the compression force actually acting is obtained from this measured value, and based on this compression force, the valve body drive unit is actually applied to the valve body by the worm. The torque that acts is known, and the diagnosis relating to the torque of the motor-operated valve is performed based on this torque.
Japanese National Publication No. WO95 / 14186 (page 3, lower right column, line 19 to page 4, upper right column, line 29, FIG2, FIG3) Japanese Patent No. 2982090 (paragraphs “0021” to [0031], FIGS. 1 to 4) Japanese Patent Laid-Open No. 7-310845 (paragraphs “0028” to “0036”, FIG. 2).

However, in the “built-in torque sensor method”, since the strain gauge is integrated on the spring cartridge side, the structure itself is complicated and expensive, and when installing the spring cartridge with strain gauge, It is necessary to open and remodel some parts, require specialized technology, require sealing management of the movable packing part of the strain gauge signal extraction part, and also to calibrate the strain gauge, the strain is integrated with the spring cartridge. There is a problem that it is necessary to take out the gauge from the motor-operated valve side and perform calibration, and the calibration work of the strain gauge is troublesome.
On the other hand, with the “torque sensor external method”, the work attached to the motor-operated valve becomes large and the workability is poor, and it is necessary to open a part of the motor-operated valve. In addition to being restricted, if such an installation operation was performed each time the torque was diagnosed, there was a problem that the amount of work increased and the diagnosis cost was high.
In addition, in the “spring compression method”, a weight meter, a position detection means, a compression means, etc. are temporarily installed on the motor-operated valve. In this case, the weight meter, etc. can be installed on each motor-operated valve. It is necessary to make necessary modifications, weight meters etc. cannot be permanently installed, and must be installed at the time of diagnosis. Since it is difficult to share and it is necessary to manufacture each motorized valve individually, there is a problem that the cost associated with the diagnosis work is high.
The “built-in torque sensor method”, “torque sensor external method” and “spring compression method” described above all obtain torque from the compression force of the spring cartridge, and use this torque to diagnose the torque of the motorized valve. It is a technique for doing.
By the way, in the actual operation of the electric valve, the driving force output from a driving source such as a motor is transmitted to the valve stem through a valve body driving unit composed of a worm, a worm wheel, a drive sleeve, and a stem nut. Therefore, when a frictional force is generated in the valve body driving unit, the driving force input to the valve body driving unit and the force transmitted from the valve body driving unit to the valve stem do not match, There will be a difference between them. For example, if the stem nut portion runs out of oil and generates frictional force, the driving force transmission efficiency in the valve body drive unit (that is, the input to the valve body drive unit and the output from the valve body drive unit) Even if the specified drive force is input, the force actually acting on the valve stem will be smaller than when there is no oil shortage. Taking into account that the matter to be diagnosed is “diagnosis relating to the driving force, ie torque”, the diagnosis relating to the driving force of the motorized valve, ie torque, is simply regarded as a constant correlation between torque and yoke stress. That is, it is not sufficient to read the torque corresponding to the yoke stress obtained by measurement, assuming that the driving force transmission efficiency is constant, and the influence of the temporal change of the driving force transmission efficiency in the valve body driving unit, etc. Also consider There is a need.
Therefore, in the present invention, the torque corresponding to the yoke stress obtained by measurement is read from the correlation between the torque and the yoke stress, and the diagnosis regarding the driving force of the motor-operated valve is performed. Reflecting this in the calculation of driving force realizes highly accurate and reliable diagnosis, and performs this diagnosis with simple operation with good workability and low cost and high accuracy even during operation of the motorized valve. The purpose of the present invention is to provide a diagnostic method for a motorized valve that can be performed and a diagnostic device suitable for carrying out this diagnostic method.

In the present invention, the following modes are adopted as specific means for solving such a problem.
In the first aspect, the valve body drive unit that opens and closes the valve body by using the rotational drive force of the worm to which the rotational drive force is applied by the electric force, and the valve body drive unit acts in the axial direction of the worm. In the motor-operated valve diagnosis method for diagnosing the driving force of a motor-operated valve having a spring cartridge that expands and contracts in response to the reaction force, the valve body drive unit at both the opening and closing of the motor-operated valve A correlation between the driving force output signal and the driving force obtained from the compression state of the spring cartridge is held as a first correlation database, and the correlation between the driving force input signal to the valve body driving unit and the driving force output signal And the change state of the driving force transmission efficiency in the valve body drive unit is monitored based on the correlation, and is obtained by measurement with reference to the first correlation database. Reading the driving force corresponding to the drive power output signal, it is characterized by performing a diagnosis of the driving force of the electric valves on the basis of the drive force.
Here, the “driving force transmission efficiency in the valve body driving unit” is a ratio of the driving force input to the valve body driving unit side and the driving force output from the valve body driving unit side, and a driving force input signal And the driving force output signal. The “monitoring of the change state of the driving force transmission efficiency” is to monitor the change state of the correlation continuously or as a spot if necessary. This is reflected in the diagnosis regarding the driving force of the electric valve.
For example, if the driving force transmission efficiency changes to a predetermined change rate or more, or changes to a predetermined value or more, it is determined that the driving force transmission system is abnormal, and the driving force corresponds to the change rate or change amount. The driving force corresponding to the output signal can be corrected to optimize the diagnosis regarding the driving force, and the deterioration tendency of the driving force transmission system can be predicted and reflected in the maintenance plan.
In addition, “diagnosis relating to driving force” refers to an element that is directly grasped as driving force, that is, torque that is a driving force input signal [torque obtained from compression force of spring cartridge, that is, spring cartridge compression force × r (r : 1/2 of the pitch circle diameter of the worm wheel)], the amount and force of compression of the spring cartridge, the current value of the motor that drives the worm, etc. It is a concept including valve stem stress and yoke stress which are force output signals.
Therefore, according to the first aspect, the first correlation between the driving force output signal from the valve drive unit and the driving force obtained from the compression force of the spring cartridge is obtained in advance and retained. Then, by referring to the first correlation database, the driving force corresponding to the driving force output signal acquired by measurement is read out, and the diagnosis relating to the driving force of the motor-operated valve is performed based on the driving force. For example, the diagnosis work is extremely simple compared to the case where a diagnosis is performed by acquiring a physical quantity of a type that is relatively difficult to measure each time the diagnosis regarding the driving force of the motorized valve is performed, and The work can be performed with good workability, and the labor saving is promoted to reduce the diagnosis cost.
For example,
a. Diagnosis of appropriateness of set torque, for example, diagnosis of appropriateness of torque value at the operation timing of the torque switch when the motorized valve is closed,
b. Diagnosis of appropriateness of the valve seat force, that is, diagnosis of appropriateness of the magnitude of the holding torque of the valve body when the motor-operated valve is closed,
c. Confirmation of margin of driving force, for example, confirmation of margin of driving force with respect to extraction torque at the time of valve body extraction when the required torque becomes maximum when the motorized valve is opened,
As a result, a total diagnosis of the driving force transmission system of the electric valve can be performed.
The ninth mode is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above to obtain the above-described effects. That is, in the ninth aspect, a valve body driving unit that opens and closes the valve body using the rotational driving force of the worm to which the rotational driving force is applied by the electric force, and the shaft of the worm in the valve body driving unit. In the motor-operated valve diagnostic device for diagnosing the driving force of a motor-operated valve having a spring cartridge that expands and contracts in response to a reaction force acting in the direction, the valve element drive at both the opening and closing of the motor-operated valve A first correlation database indicating a correlation between a driving force output signal from the portion and a driving force obtained from the compression state of the spring cartridge, a driving force input signal to the valve body driving portion, and the driving force output signal. The monitoring means for acquiring the correlation and monitoring the change state of the driving force transmission efficiency in the valve body driving unit based on the correlation, and the first correlation database are used for measurement. Reading the driving force corresponding to the drive power output signal, it is characterized in that a diagnostic means for performing diagnosis of the driving force of the electric valves on the basis of the drive force.
According to a second aspect, in the motor-operated valve diagnosis method according to the first aspect, the change state of the driving force transmission efficiency is monitored, and the change state is reflected in the calculation of the driving force corresponding to the driving force output signal. It is a feature.
Here, to reflect the change state of the driving force transmission efficiency in the calculation of the driving force is, for example, when the driving force transmission efficiency changes to a predetermined change rate or changes to a predetermined value or more. The first correlation database is corrected in accordance with the change rate or the change value, and the driving force is calculated based on the corrected first correlation database.
Therefore, according to the motor-operated valve diagnosis method according to the second aspect, the driving force is calculated based on the first correlation database corrected according to the driving force transmission efficiency in the valve body driving unit, and based on this By performing diagnosis regarding the driving force of the motorized valve, more accurate and reliable diagnosis is realized.
The tenth aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, in the tenth aspect, in the motor-operated valve diagnostic apparatus according to the ninth aspect, the change state of the driving force transmission efficiency is monitored, and the change state is calculated for the driving force corresponding to the driving force output signal. It is characterized by having a calculation means for reflecting.
According to a third aspect, in the motor-operated valve diagnosis method according to the first aspect, a yoke stress acting on the yoke is used as the driving force output signal.
Here, when the yoke stress is used as the driving force output signal, the yoke stress can be directly measured by attaching a sensor such as a strain sensor to the outer surface of the yoke exposed to the outside of the motor-operated valve, and whether the motor-operated valve is operated or not. Regardless of this, since it is possible to always measure, the change state of the driving force transmission efficiency can be continuously monitored. Further, since the yoke stress is obtained as a voltage signal output from the strain sensor, it cannot be directly obtained as the valve stem stress, but is obtained quantitatively. It is suitable for learning the change tendency.
Furthermore, since the yoke stress can be measured at the part exposed on the outer surface of the motor-operated valve, for example, when measuring a stress by opening a part of the motor-operated valve and attaching a strain gauge inside the motor-operated valve. In comparison, the work is much easier, and as a result, the diagnostic workability can be further improved and the diagnostic cost can be further reduced by labor saving.
The eleventh aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, the eleventh aspect is characterized in that, in the motor-operated valve diagnostic apparatus according to the ninth or tenth aspect, a yoke stress acting on the yoke is used as the driving force output signal.
According to a fourth aspect, in the motor-operated valve diagnosis method according to the third aspect, a second correlation database showing a correlation between the valve stem stress acting on the valve stem as the driving force output signal and the yoke stress is provided. Based on the valve stem stress that is stored and read corresponding to the yoke stress obtained by measurement with reference to the second correlation database, and the driving force input signal obtained by measurement, the valve body It is characterized by monitoring the change state of the driving force transmission efficiency in the driving unit.
Here, although the said valve stem stress is grasped | ascertained as a driving force output signal from the said valve body drive part, direct measurement during the driving | operation of a motor operated valve is restrict | limited. However, since the yoke stress is grasped as a driving force output signal from the valve body drive unit as well as the valve stem stress and can be always measured even during operation of the motorized valve, the correlation between the yoke stress and the valve stem stress is obtained. If the relationship is held as the second correlation database, thereafter, the valve stem stress as a driving force output signal is read out and acquired by referring to the second correlation database based on the yoke stress acquired by measurement. can do. Therefore, for example, the diagnosis work is extremely simple and the work can be performed with good workability compared to the case where the diagnosis is performed by obtaining the valve stem stress each time the motor-operated valve is diagnosed. Reduction of diagnosis cost is promoted by the conversion.
The correlation between the valve stem stress and the yoke stress is, for example, that when a motor-operated valve can be operated to the fully closed side, a known value of load (axial force) is applied to the valve stem, and the valve stem stress at that time And yoke stress (for example, both are acquired as a voltage signal by the strain sensor).
Furthermore, since the valve stem stress is obtained numerically and accurately, a friction coefficient “μ” between the valve stem and the stem nut can be obtained, and whether or not this is within an appropriate range can be diagnosed with high accuracy. it can. That is, the friction coefficient “μ” is a well-known friction coefficient calculation formula “= [A × (torque / valve stem stress) −B × d] / [d + C × (torque / valve stem stress)]. D is the effective stem diameter. , A, B, and C are constants. In this calculation formula, all the elements other than “torque / valve stem stress” are constant values, and therefore the ratio of the torque to the stem pressure “ By obtaining the “torque / valve stem stress”, it is possible to obtain the friction coefficient “μ” of the valve body drive unit and diagnose its suitability. As a result, quantitative comparison diagnosis with the design value etc. of the motorized valve It is possible to quantitatively and easily determine whether the frictional state (lubricating state) of the valve body drive unit is normal or abnormal, and the reliability of the valve body drive unit is improved accordingly. Become.
By the way, in the actual operation of the motor-operated valve, the driving force output from a driving source such as a motor is transmitted to the valve stem through the valve body driving unit. When this occurs, the driving force input to the valve body drive unit and the force transmitted from the valve body drive unit to the valve rod do not coincide with each other, resulting in a difference between the two. For example, if the stem nut portion runs out of oil and generates frictional force, the driving force transmission efficiency in the valve body drive unit (that is, the input to the valve body drive unit and the output from the valve body drive unit) Even if a specified driving force is input, the force actually acting on the valve stem is smaller than when no oil shortage occurs. Therefore, the force acting directly on the valve body (= [valve stem stress as a driving force output signal] − [sliding of packing, etc.), which is a matter to be diagnosed as the original function of the motorized valve (closing function, etc.) Dynamic resistance]-[fluid pressure]), that is, it is important to obtain the valve stem stress acting on the valve stem. In this case, the yoke stress can be obtained by measurement as a reaction force of the valve stem stress. Diagnosing the force acting directly on the valve body, such as the closing function (seat force), based on the valve stem stress corresponding to the yoke stress, obtains a highly reliable diagnosis result for the entire motor-operated valve be able to.
A twelfth aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, in the twelfth aspect, in the motor-operated valve diagnostic apparatus according to the eleventh aspect, the correlation between the valve stem stress acting on the valve stem as the driving force output signal, the yoke stress, and the valve stem stress. A second correlation database showing, the valve stem stress read out corresponding to the yoke stress obtained by measurement with reference to the second correlation database, and the driving force input signal obtained by measurement On the basis of this, a monitoring means for monitoring the change state of the driving force transmission efficiency in the valve body driving unit is provided.
In a fifth aspect of the present application, in the motor-operated valve diagnosis method according to the first, second, third, or fourth aspect, the driving force input signal is a current value signal corresponding to the driving force or the spring cartridge. It is a compression amount signal corresponding to the compression amount or a compression force signal corresponding to the compression force of the spring cartridge.
Among these driving force input signals, the current value signal is a motor-operated valve by a current value sensor (for example, a magnetic sensor described later) disposed on the outside of the conduit containing the electric wire as a current value supplied to the motor. Can be obtained by continuous measurement during operation. The current value acquired by this measurement is numerically grasped as the driving force corresponding to the current value based on the correlation between the current value obtained in advance and the driving force.
The amount of compression of the spring cartridge is, for example, both when the motor-operated valve is opened and closed by a laser sensor or a differential transformer (so-called “LVDT”) attached to the outer end of the spring cartridge in the axial direction. The amount of movement of the worm can be obtained by measurement even during operation of the electric valve. In particular, when a laser sensor having a compact form is adopted, the laser sensor can be permanently installed in the motor-operated valve, and the compression amount of the spring cartridge can be obtained by continuous measurement during operation of the motor-operated valve. The compression amount acquired by this measurement is grasped numerically as a driving force based on the spring characteristics of the spring cartridge obtained in advance, that is, the correlation between the compression amount and the compression force.
The compressive force of the spring cartridge can be obtained by continuous measurement during the operation of the motor-operated valve both when the motor-operated valve is opened and when the motor-operated valve is closed by attaching a strain sensor to the spring cartridge. . As described above, the driving force is directly acquired by calculation as the product of the compressive force and the pitch circle diameter of the worm wheel.
Each of these driving force input signals is one of the criteria for determining the driving force transmission efficiency in the valve body driving unit, and it is necessary that an accurate correlation with the driving force is always secured. Therefore, it is calibrated by an appropriate method. For example, the current value can be calibrated by a load cell attached to the shaft end side of the spring cartridge. The compression amount and compression force of the spring cartridge can be calibrated by operating the motorized valve with a load cell attached to the spring cartridge, and the spring cartridge is compressed from the outside while the motorized valve is stopped, or the spring Each cartridge can be calibrated by removing it from the motorized valve and compressing it in a single state.
Thus, according to the motor-operated valve diagnosis method according to the fifth aspect, the driving force input signal to the valve body drive unit is the current value signal, the compression amount signal, or the compression force signal, and these measurements And calculating the driving force numerically, it is possible to select the most suitable sensor for acquiring the driving force input signal, and the accuracy of the acquired driving force is high, based on the acquired driving force. Thus, a diagnosis with respect to the driving force of the motor-operated valve can be performed to achieve a highly accurate and reliable diagnosis.
The thirteenth aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, in the thirteenth aspect, in the motor-operated valve diagnostic device according to the ninth, tenth, eleventh or twelfth aspect, as the driving force input signal, a current value signal corresponding to the driving force or the spring cartridge. A compression amount signal corresponding to the compression amount or a compression force signal corresponding to the compression force of the spring cartridge is used.
According to a sixth aspect of the present application, in the motor-operated valve diagnosis method according to the fifth aspect, the driving force input signal is a current value signal corresponding to the driving force, and the current value signal is a current value of a conduit that houses an electric wire. It is obtained based on signal information output from a plurality of magnetic sensors attached to the outer surface.
Here, the magnetic sensor is a sensor using a Hall element, and generates a voltage corresponding to the magnitude of the magnetism when sensing magnetism from the electric wire housed in the conduit. Based on the correlation between the output signal and the driving force, the driving force from the electric motor can be acquired.
In this case, the electric wire is accommodated in the electric conduit, but the positional relationship of the electric wire in the electric conduit is uncertain. Therefore, when one magnetic sensor is used, the magnetism is clearly determined depending on the position of the electric wire. It may be impossible to detect. For this reason, in the present invention, by attaching a plurality of the magnetic sensors to the outside of the conduit, the magnetism can be accurately measured regardless of the position of the wire within the conduit. Furthermore, in this case, the magnetic measurement function is further enhanced by mounting the plurality of magnetic sensors on one surface orthogonal to the axial direction of the conduit and at the same pitch in the circumferential direction of the conduit. As a result, the reliability of the driving force acquired based on the measurement signal is improved.
The fourteenth aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, according to the fourteenth aspect, in the motor-operated valve diagnostic apparatus according to the thirteenth aspect, a plurality of the current value signals as the driving force input signals are attached to the outer surface of the conduit containing the electric wires. A driving force input signal acquisition means for acquiring the signal based on signal information output from the magnetic sensor is provided.
In a seventh aspect, in the motor-operated valve diagnosis method according to the fifth aspect, a driving force input signal to the valve body drive unit is a compression amount signal corresponding to the compression amount of the spring cartridge, and the compression amount signal is A contactor which is provided on an adapter fixed to the outer surface side of the motor-operated valve so as to be contactable / non-contactable with the shaft end side of the spring cartridge and which deviates following the compression displacement of the spring cartridge in the contact state. It is obtained based on displacement information in the axial direction.
Here, since the contact is provided in an adapter fixed to the outer surface side of the motor-operated valve, when measuring the compression amount as a driving force input signal, the characteristics of the spring cartridge are directly set. And it can measure easily from the outside of a motor operated valve. Therefore, coupled with the fact that both the yoke stress or the valve stem stress as the driving force output signal can be easily measured from the outside of the motor-operated valve by the strain sensor attached to the yoke, the measurement work is facilitated.
Further, when the compression amount is not measured, the contact can be brought into a non-contact state on the shaft end side of the spring cartridge, so that the operation of the spring cartridge is not hindered by the contact. . Furthermore, by attaching the contact to the adapter in an oil-tight manner, there is no need to open the outer end side of the spring cartridge when measuring the amount of compression using the contact. As in the case of opening the spring cartridge, a situation of leakage of grease from the spring cartridge side is avoided in advance.
The fifteenth aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, in the fifteenth aspect, in the motor-operated valve diagnostic apparatus according to the thirteenth aspect, the compression amount signal as the driving force input signal is provided in an adapter fixed to the outer surface side of the motor-operated valve. Driving force input signal acquisition means for acquiring contact based on displacement information in the axial direction of the contact that can be contacted and non-contacted with the shaft end side of the spring cartridge and is displaced following the compression displacement of the spring cartridge in the contact state. It is characterized by having.
According to an eighth aspect, in the electric valve diagnosis method according to the third aspect, the compression force and the compression amount of the spring cartridge are obtained and held by measurement, while the electric valve is opened and closed. In both cases, the yoke stress and the accurate compression amount in which the backlash amount in the expansion / contraction direction of the spring cartridge is acquired and held, and the opening operation is obtained from the held compression amount, the compression force, and the yoke stress. The correlation between the driving force and the yoke stress in both the closed operation and the closed operation is acquired as the first correlation database, and the yoke stress acquired by measurement with reference to the first correlation database The driving force corresponding to is read out.
Here, as the compression amount, an accurate compression amount in which the backlash amount in the expansion / contraction direction of the spring cartridge is removed by calculation is acquired, and the first correlation database is acquired based on the compression amount. By referring to the correlation database, the driving force read out corresponding to the yoke stress obtained in the measurement is accurate without play and the diagnosis of the driving force with high accuracy and high reliability becomes possible. .
The sixteenth aspect is proposed as a motor-operated valve diagnostic apparatus for carrying out the motor-operated valve diagnostic method as described above and obtaining the above-described effects. That is, in the sixteenth aspect, in the motor-operated valve diagnostic apparatus according to the eleventh aspect, the amount of play in the expansion / contraction direction of the spring cartridge is determined by the yoke stress and measurement both during opening and closing of the motor-operated valve. First acquisition means for acquiring and holding the exact compression amount removed by the calculation, second acquisition means for acquiring and holding the compression force and compression amount of the spring cartridge by measurement, and these holdings A first correlation database indicating a correlation between the driving force and the yoke stress in both the opening operation and the closing operation, which are obtained from the compressed amount, the compression force, and the yoke stress, and the first correlation database; With reference to the driving force reading means for reading the driving force corresponding to the yoke stress obtained by the measurement, the driving force reading means is provided.

  As described above, according to the motor-operated valve diagnosis method and motor-operated valve diagnosis apparatus according to the present invention, the torque corresponding to the yoke stress obtained by measurement is read out from the correlation between the torque and the yoke stress. In the diagnosis of valve driving force (torque), highly accurate and reliable diagnosis is realized by reflecting the change in driving force transmission efficiency in the calculation of the driving force. Even during the operation of the motor-operated valve, the operation can be performed with a simple operation with good workability and at a low cost with high accuracy. In addition, it is possible to diagnose the entire driving force transmission system from the driving unit side to the valve body side of the electric valve and diagnose the change with time in the transmission state of the driving force, that is, to manage the tendency of the driving force transmission efficiency.

Hereinafter, a motor-driven valve diagnosis method and diagnosis apparatus according to the present invention will be described in detail based on preferred embodiments.
First, prior to the description of the diagnostic method according to the present invention, the structure of the drive system of the motor-operated valve will be described with reference to FIGS.
FIG. 1 shows a main part of a normal motor-driven valve drive system (hereinafter referred to as “first motor-driven valve drive system”) to which the diagnosis method according to the present invention is applied. FIG. 2 also shows an electric valve drive system (hereinafter referred to as “second electric valve drive system”) in which a built-in torque sensor (with a strain gauge attached to a movable shaft near the spring cartridge) is installed. The main part is shown.
A: First electric valve drive system
In FIG. 1, reference numeral 1 denotes a valve stem having a valve body (not shown) connected to the lower end thereof, and a stem nut 2 is screwed into a screw portion on the upper side of the valve stem. Further, the stem nut 2 is inserted into and fixed to a cylindrical drive sleeve 3 and integrated therewith. The drive sleeve 3 is rotatable integrally with a worm wheel 4 fitted and arranged on the outer peripheral side thereof, and transmits the rotational force of the stem nut 2 to the valve stem 1 as its axial displacement force. The valve element is opened / closed (lifted / lowered) via the valve rod 1. The valve rod 1 can only move in the axial direction, and its rotation is restricted.
A worm 5 is engaged with the worm wheel 4, and the worm 5 is rotated by a motor (not shown) via a motor shaft 6, whereby the worm wheel 4 is rotated and the rotational force is It is transmitted to the valve stem 1 through the stem nut 2 as its lifting drive force.
The motor shaft 6 is provided with a spline 6a. When the worm 5 is spline-fitted to the spline 6a, the worm 5 receives the rotational force from the motor shaft 6, but its axial direction. It can be moved in the direction of arrow RL.
The worm 5 has one end side extended in the axial direction to form an extended cylindrical portion 7. A circumferential groove 8 is provided on the outer periphery of the extended cylindrical portion 7, and an actuator 9 a of a torque switch 9 is engaged with the circumferential groove 8. The torque switch 9 operates when the worm 5 moves in the axial direction from its neutral position and the amount of movement reaches a predetermined value, and generates a stop signal for the motor to stop it. The excessive torque is transmitted to the valve stem 1 side to protect it.
A bearing 10 is fixed to the end of the extended cylindrical portion 7 of the worm 5 with a nut 11, and a movable shaft 12 described below is connected to the end of the extending cylindrical portion 7 through the bearing 10 so as to be relatively rotatable. The movable shaft 12 is a different-diameter cylindrical body having a large-diameter cylindrical portion 12a into which the bearing 10 is inserted and connected, and a small-diameter cylindrical portion 12b continuous to the large-diameter cylindrical portion 12a. Along with the movement in the axial direction, it moves in the axial direction integrally therewith. A spring cartridge 13 described below is attached to the small-diameter cylindrical portion 12b of the movable shaft 12.
The spring cartridge 13 generates a predetermined holding torque on the worm wheel 4 via the worm 5 after the valve body is fully opened or fully closed. Between one washer 14 disposed on the stepped surface side between the portion 12a and the small diameter cylindrical portion 12b and the other washer 15 disposed on the nut 16 side screwed to the end of the small diameter cylindrical portion 12b. In addition, a plurality of disc springs 17 are alternately mounted so as to face each other and with a required tension load applied thereto.
The axial length of the spring cartridge 13 in a single state (that is, the outer dimension between the washers 14 and 15 when a predetermined tension load is generated) is the same as that of the large-diameter cylindrical portion 12a of the movable shaft 12. It is fixedly held at a predetermined value by the step surface between the small diameter cylindrical portion 12b and the seat surface of the nut 16.
Further, of the movable shaft 12 and the spring cartridge 13, the movable shaft 12 is fitted into a small diameter hole portion 19 provided coaxially with the worm 5, and the spring cartridge 13 is inserted into the small diameter hole portion 19. The movable shaft 12 can be moved in the axial direction within the small-diameter hole 19, and the spring cartridge 13 can be expanded and contracted within the large-diameter hole 20. It is possible.
The washer 14 disposed on one end side of the spring cartridge 13 is moved further in the direction of the arrow L by engaging with the shoulder portion 21 between the small diameter hole portion 19 and the large diameter hole portion 20. Is regulated. Further, the washer 15 disposed on the other end side of the spring cartridge 13 abuts on the end surface 45a of the cartridge retainer 45 attached to the outer end of the large-diameter hole portion 20, thereby further moving in the arrow R direction. Movement is restricted. The cartridge retainer 45 also has a function as a cap that covers and protects the outer end side of the spring cartridge 13 during normal operation.
In the first electric valve drive system, the spring cartridge 13 is expanded and contracted according to the compression force acting on the spring cartridge 13, and the torque switch 9 is operated, whereby the valve rod 1 side (that is, the valve body side). ) To prevent an excessive load from being input without fail and to ensure safe and reliable operation of the motor-operated valve. Reference numeral 18 denotes a torque limit sleeve that regulates the maximum amount of compression displacement of the disc spring 17.
B: Second electric valve drive system
In FIG. 2, reference numeral 1 denotes a valve stem having a valve body (not shown) connected to the lower end thereof, and a stem nut 2 is screwed into a screw portion on the upper side of the valve stem. Further, the stem nut 2 is inserted into and fixed to a cylindrical drive sleeve 3 and integrated therewith. The drive sleeve 3 is rotatable integrally with a worm wheel 4 fitted and arranged on the outer peripheral side thereof, and transmits the rotational force of the stem nut 2 to the valve stem 1 as its axial displacement force. The valve element is opened / closed (lifted / lowered) via the valve rod 1. The valve rod 1 can only move in the axial direction, and its rotation is restricted.
A worm 5 is engaged with the worm wheel 4, and the worm 5 is rotated by a motor (not shown) via a motor shaft 6, whereby the worm wheel 4 is rotated and the rotational force is It is transmitted to the valve stem 1 through the stem nut 2 as its lifting drive force.
The motor shaft 6 is provided with a spline 6a. When the worm 5 is spline-fitted to the spline 6a, the worm 5 receives the rotational force from the motor shaft 6, but its axial direction. It can be moved in the direction of arrow RL.
The worm 5 has one end side extended in the axial direction to form an extended cylindrical portion 7. A circumferential groove 8 is provided on the outer periphery of the extended cylindrical portion 7, and an actuator 9 a of a torque switch 9 is engaged with the circumferential groove 8. The torque switch 9 operates when the worm 5 moves in the axial direction from its neutral position and the amount of movement reaches a predetermined value, and generates a stop signal for the motor to stop it. The excessive torque is transmitted to the valve stem 1 side to protect it.
A bearing 10 is fixed to the end of the extended cylindrical portion 7 of the worm 5 with a nut 11, and a movable shaft 12 described below is connected to the end of the extending cylindrical portion 7 through the bearing 10 so as to be relatively rotatable. The movable shaft 12 is a different-diameter cylindrical body having a large-diameter cylindrical portion 12a into which the bearing 10 is inserted and connected, and a small-diameter cylindrical portion 12b continuous to the large-diameter cylindrical portion 12a. Along with the movement in the axial direction, it moves in the axial direction integrally therewith. A spring cartridge 13 described below is attached to the small-diameter cylindrical portion 12b of the movable shaft 12.
The spring cartridge 13 generates a predetermined holding torque on the worm wheel 4 via the worm 5 after the valve body is fully opened or fully closed. One washer 14 disposed on the step surface side between the portion 12a and the small diameter cylindrical portion 12b, and the other washer 15 disposed on the nut 26 described later screwed to the end of the small diameter cylindrical portion 12b, In between, a plurality of disc springs 17 are alternately mounted so as to face each other and with a required tension load applied thereto.
The axial length of the spring cartridge 13 in a single state (that is, the outer dimension between the washers 14 and 15 when a predetermined tension load is generated) is the same as that of the large-diameter cylindrical portion 12a of the movable shaft 12. It is fixed and held at a predetermined value by the step surface between the small diameter cylindrical portion 12b and the seat surface of the nut 26.
Further, of the movable shaft 12 and the spring cartridge 13, the movable shaft 12 is fitted into a small diameter hole portion 19 provided coaxially with the worm 5, and the spring cartridge 13 is inserted into the small diameter hole portion 19. The movable shaft 12 can be moved in the axial direction within the small-diameter hole 19, and the spring cartridge 13 can be expanded and contracted within the large-diameter hole 20. It is possible.
The washer 14 disposed on one end side of the spring cartridge 13 is moved further in the direction of the arrow L by engaging with the shoulder portion 21 between the small diameter hole portion 19 and the large diameter hole portion 20. Is regulated. Further, the washer 15 disposed on the other end side of the spring cartridge 13 is brought into contact with an end surface 42a of the cartridge presser 42 described below disposed near the outer end of the large-diameter hole portion 20, thereby further The movement in the direction of arrow R is restricted.
The cartridge retainer 42 is formed of a stepped cylindrical body having a large diameter portion and a small diameter portion, and is fixedly held by an adapter 38 that is bolted to the end surface of the casing. The washer 15 is supported by the end surface 42a on the large diameter portion side. Restrict movement of
On the other hand, a strain gauge 37 is stuck on the end face of the large-diameter cylindrical portion 12 a of the movable shaft 12 in a non-contact state with the one washer 14. This strain gauge 37 is a characteristic component in the second electric valve drive system, and is a load (that is, a load applied to the movable shaft 12 as the spring cartridge 13 is compressed in the arrow L direction and the R direction). The compression force of the spring cartridge 13) is measured as strain displacement, and the measurement data is taken out and used as diagnostic data for the motor-operated valve.
The nut 26 is constituted by a deformed nut comprising a main body portion 26a screwed into an end portion of the small diameter cylindrical portion 12b and a cylindrical extending portion 26b extending coaxially from one end side of the main body portion 26a. The lead wire 41 is pulled out from the strain gauge 37 side through the inner hole, and a connector 48 is attached to the tip thereof.
Further, the extended portion 26 b of the nut 26 is fitted inside the small diameter portion of the cartridge retainer 42, and an O-ring 24 is disposed between the inner periphery of the cartridge retainer 42. The O-ring 24 seals the shaft between the cartridge retainer 42 and the nut 26 that moves relative to the cartridge retainer 42 in the axial direction. An O-ring 25 is disposed between the outer peripheral surface of the large-diameter portion of the cartridge retainer 42 and the inner peripheral surface of the adapter 38. The connector 48 faces outward from the end face of the cartridge retainer 42, but a cap 46 is attached to the cartridge retainer 42 during normal operation.
By the way, in order to maintain the original function for a long period of time in the motor-operated valve, for example, the soundness of the valve body drive unit that transmits the rotational force of the worm to the valve body side, including the motorized part or the worm, for example. In addition to confirming the above, it is possible to appropriately perform a diagnosis on the driving force, such as whether the valve element is driven with an appropriate driving force, and whether an appropriate holding torque is secured in the fully opened / closed state of the valve element. As described above, it is necessary.
Among these various diagnostic items, in order to obtain diagnostic data especially in the diagnosis relating to the driving force, at the time of diagnosis of the motor-operated valve, the sensor unit 30 described below is used in the cartridge in the first motor-operated valve driving system. Instead of the presser 45, it is temporarily attached. In the second electric valve drive system, the strain gauge 37 is permanently installed.
First, in the first electric valve drive system (see FIG. 1), as shown in FIG. 3, the cartridge presser 45, which is always mounted during normal operation of the electric valve, is removed from the casing side. A configuration in which the sensor unit 30 described below is temporarily mounted on the outer end side of the spring cartridge 13, and the compression amount of the spring cartridge 13 and the compression force acting thereon are measured and acquired under the operation state of the motor-operated valve. It is said that.
The sensor unit 30 abuts and fixes a flanged cylindrical adapter 31 on the end surface 22 of the casing via a packing 23 so as to cover the end portion side of the large-diameter hole portion 20, and the outside of the adapter 31. The sensor holder 32 is attached to the end face. A plate-shaped load cell 33 is disposed between the outer end surface of the adapter 31 and the end surface of the sensor holder 32 so as to bisect the space between the two in the axial direction. A strain gauge 35 is attached to the load cell 33 and one end of a core 36 is connected to the load cell 33. Further, the other end of the core 36 is brought into contact with the washer 15 on the spring cartridge 13 side to restrict the washer 15 from moving further in the arrow R direction. Accordingly, the compressive force applied to the spring cartridge 13 is transmitted from the washer 15 to the load cell 33 via the core 36, and is detected by the strain gauge 35 as a strain amount (voltage value) in the load cell 33. Based on this, the compression force applied to the spring cartridge 13 is acquired.
Of the section on the adapter 31 side and the section on the sensor holder 32 side partitioned by the load cell 33, the nut 16 is positioned inside the core 36 in the space on the adapter 31 side. The approach is arranged. A laser sensor 34 is disposed in the space on the sensor holder 32 side. The laser sensor 34 faces the nut 16 attached to the tip of the movable shaft 12 through a through hole (not shown) provided in the load cell 33 and the core 36, and the position of the top surface of the nut 16 is determined. By measuring, the amount of movement of the worm 5 in the axial direction, that is, the amount of compression of the spring cartridge 13 is measured. Specifically, a “measurement point” is set on the top surface of the nut 16 and the distance (interval) from the laser sensor 34 to the measurement point is measured.
In addition to the load cell 33 and the laser sensor 34, as shown in FIG. 6, as a diagnostic data acquisition means, a valve box 61 in which a valve body is housed, a valve body in which the worm wheel 4, the worm 5 and the like are housed. In order to measure the stress acting on the yoke 50 disposed so as to cover the valve rod 1 between the drive unit 62, that is, the yoke stress, the pair of left and right support columns 53 and 54 of the yoke 50 are respectively measured. The strain gauges 51 and 52 are installed, and in order to measure the stress acting on the valve stem 1, that is, the valve stem stress, the strain gauge 55 is installed on the valve stem.
Since the valve stem 1 moves up and down with the operation of the motorized valve, in many cases, the strain gauge 55 can be installed directly on the valve stem 1 within the range where the strain gauge 55 can be seen from the outside. Limited to operation. However, for example, when it is desired to monitor the change state of the driving force transmission efficiency based on the valve stem stress, it is necessary to continuously acquire the valve stem stress. In such a case, for example, when the operation of the motor-operated valve to the fully closed side is possible, a known value of load (axial force) is applied to the valve stem, and the yoke stress in that case is applied to the strain gauges 51 and 52. The correlation between the valve stem stress and the yoke stress is acquired as a correlation database. Thereafter, a method of reading the valve stem stress corresponding to the yoke stress obtained by measurement with reference to the correlation database is employed.
Further, as shown in FIGS. 7 and 8, in order to measure the current value of the motor, a plurality of magnetic sensors 60 are arranged on the outer surface of a conduit 61 in which an electric wire 62 is housed. As described above, the magnetic sensor 60 is a sensor using a Hall element. When the magnetism from the electric wire 62 accommodated in the conduit 61 is sensed, a voltage corresponding to the magnitude of the magnetism is obtained. The driving force from the electric motor can be acquired based on the correlation between the output signal and the driving force.
In this case, the electric wire 62 is housed in the electric conduit 61, but the positional relationship of the electric wire 62 in the electric conduit 61 is uncertain. Therefore, when one magnetic sensor is used, the position of the electric wire is not determined. Depending on the situation, the magnetism may not be clearly detected. For this reason, here, a plurality of the magnetic sensors 60 are attached to the outer surface of the conduit 61, and the number of the magnetic sensors 60 is as shown by a solid line in FIG. 8 when the wire 62 is a two-phase wire. 2 or a multiple of 2 (that is, 4 or 6), and when the electric wire 62 is a three-phase wire, a multiple of 3 or 3 as shown by a chain line in FIG. (In other words, six, nine, etc.), and in this case, the plurality of magnetic sensors 60 are arranged on one surface orthogonal to the axial direction of the conduit 61 and around the conduit 61. By attaching them at the same pitch in the direction, the magnetic signal can be obtained as a clear and stable, gradual and smooth signal waveform regardless of the position of the wire 62 inside the conduit 61. .
In the conventional clamp type magnetic sensor, the positional relationship of the magnetic sensor with respect to the electric wire in the conduit differs every time measurement is performed (that is, every time the magnetic sensor is attached). Have difficulty. For this reason, here, each magnetic sensor 60 is fixedly attached to the conduit 61 so that the positional relationship of the magnetic sensor 60 with respect to the conduit 61 is always kept constant. High measurement is possible.
By the way, the sensor unit 30 moves in both the closing operation (when moving in the direction of arrow R) and the opening operation (when moving in the direction of arrow L) of the worm 5 (that is, the actual compression amount of the spring cartridge 13). The amount by which the play of the spring cartridge is added) can be measured by the laser sensor 34, but the compression force on the spring cartridge 13 is either the closing operation or the opening operation due to the function of the load cell 33. Only one side (closed operation side in this embodiment) can be measured, and the other side (open operation side) cannot be measured. Therefore, when acquiring the compression force on the open operation side, as described later, there is a method for obtaining based on the correlation between the compression amount and the compression force on the close operation side and the compression amount at the time of the open operation without depending on actual measurement. Be taken.
On the other hand, in the second electric valve drive system (see FIG. 2), the strain gauge 37 is attached on the end surface of the large-diameter cylindrical portion 12a of the movable shaft 12, so that the compression force of the spring cartridge 13 is increased. Can be directly measured and acquired in both the closing operation and the opening operation.
However, the strain gauge 37 needs to be calibrated, and for this calibration, the sensor unit 40 having a configuration substantially the same as that attached to the first electric valve drive system as shown in FIG. Instead of the adapter 38, the cartridge retainer 42 and the cap 46, the strain gauge 37 is calibrated by the load cell 33 and the laser sensor 34 of the sensor unit 40 temporarily attached to the outer end side of the spring cartridge 13. Like to do.
That is, the sensor unit 40 abuts and fixes the flanged cylindrical adapter 39 on the end surface 22 of the casing via the packing 23 so as to cover the end portion side of the large-diameter hole portion 20. The sensor holder 32 is attached to the outer end of the lens. A plate-shaped load cell 33 is disposed between the outer end of the adapter 39 and the end surface of the sensor holder 32 so as to bisect the space between the two in the axial direction. A strain gauge 35 is attached to the load cell 33 and one end of a core 43 is connected to the load cell 33. The other end 43a of the core 43 is in contact with the washer 15 on the spring cartridge 13 side to restrict the washer 15 from moving further in the arrow R direction. Accordingly, the compressive force applied to the spring cartridge 13 is transmitted from the washer 15 to the load cell 33 via the core 43, and is detected by the strain gauge 35 as a strain amount in the load cell 33, and based on the strain amount, The compressive force applied to the spring cartridge 13 is acquired.
Among the section on the adapter 39 side and the section on the sensor holder 32 side partitioned by the load cell 33, the nut 26 is positioned in the core 43 in the space on the adapter 39 side. The approach is arranged. And in order to take out the signal wire | line 44 from the said connector 48 attached to the front-end | tip of this nut 26 to the exterior side, the slits 27 and 28 are provided in the surrounding wall of the said adapter 39 and the said core 43, respectively.
A laser sensor 34 is disposed in the space on the sensor holder 32 side. This laser sensor 34 faces the nut 26 attached to the tip of the movable shaft 12 through a through hole (not shown) provided in the load cell 33 and the core 43, and the position of the top surface of the nut 26 or By measuring a predetermined position of the connector 48, the axial movement amount of the worm 5, that is, the compression amount of the spring cartridge 13 is indirectly measured.
Here, as described above, the strain gauge 37 is calibrated by the load cell 33 and the laser sensor 34 of the sensor unit 40. However, the present invention is not limited to such a configuration. Applying the above-mentioned “spring compression method”, the disk spring of the spring cartridge is compressed from the outside under the operation stop state of the motor-operated valve, and based on the correlation between the compression force on the spring cartridge and the compression amount in that case The strain gauge 37 can be calibrated.
Further, when the strain gauge 37 has been calibrated in the second electric valve drive system (see FIG. 2), the compressive force applied to the spring cartridge 13 can thereby be acquired both during the closing operation and during the opening operation. (For example, as will be described later, the compression force and the compression amount applied to the spring cartridge 13 are constantly measured to obtain a torque curve, and the deterioration of the spring cartridge 13 is diagnosed from the change in the torque curve). From the viewpoint, as shown in FIG. 5, a sensor holder 47 having only the laser sensor 34 can be attached in place of the cap 46.
The same viewpoint as above, and the grease sealed in the valve body drive unit prevents the laser sensor from making it difficult to measure reflected light. From the viewpoint of preventing leakage of grease and the like, FIGS. 9 to 13 show a measurement structure provided with a contact 70.
In FIG. 9, reference numeral 65 denotes an adapter fastened and fixed on the end surface 22 of the casing 1 so as to contain the nut 16 attached to the end of the movable shaft 12 on the spring cartridge 13 side. . The adapter 65 includes an end face wall 65a facing the nut 16, and an outer surface of the end face wall 65a is integrally formed with a cylindrical portion 66 having an outer peripheral surface on which screws are engraved. A shaft hole 67 is provided at the axial center position of the end face wall 65 a, and a contactor 70 described below is fitted into the shaft hole 67 so as to be slidable in the axial direction. The shaft is sealed by the provided O-ring 68.
The contact 70 is provided with a large-diameter disk-shaped contact body 71 at one end near the nut 16 and a C-ring 72 is attached to the other end, as shown by a solid line in FIG. A non-use position where the abutment body 71 abuts and engages with the inner surface of the end face wall 65a by moving outward in the axial direction, and moving inward in the axial direction as shown by a chain line in FIG. The abutment body 71 is movable between use positions where the abutment body 71 abuts and engages with the top surface of the nut 16 or the end surface of the movable shaft 12. Further, a screw hole 73 for connecting an extension rod 81 described later is provided on the other end surface of the contact 70.
Further, as shown in FIGS. 9 and 10, a stopper 75 formed in a substantially L shape is pivotally supported on the end wall 65 a side by a pin 76 inside the cylindrical portion 66 of the adapter 65. It is possible to rotate about 76 as a rotation center. In this case, the stopper 75 can be engaged with the inner surface of the C-ring 72 on the side of the contactor 70, the tip portion of which protrudes outward from the end surface of the cylindrical portion 66 by a predetermined dimension. It is dimensioned to such a length.
As shown in FIGS. 9 and 10, the stopper 75 rotates by its own weight when no external force is applied to the stopper 75, and abuts on the inner peripheral surface of the cylindrical portion 66 and is held in position. On the other hand, as shown in FIGS. 11 and 12, in the state where the cap 69 is attached to the cylindrical portion 66, the cylindrical portion 66 rotates toward the axial center, and the outer surface of the end wall 65a and the non-use position. It is positioned and held between the C-rings 72 on the contact 70 side.
As shown in FIG. 11, the cap 69 has a bottomed double cylindrical shape having an outer cylinder 69a and an inner cylinder 69b. The cap 69 is fitted on the inner surface side of the outer cylinder 69a to the cylindrical portion 66 of the adapter 65. An internal thread to be screwed is formed. The inner cylinder 69b has an inner space 69c into which the stopper 75 can be fitted.
Therefore, as shown in FIG. 11, in the state where the cap 69 is attached to the adapter 65, the contactor 70 is fixed to the non-use position by the stopper 75, and the non-use position is moved to the use position. Movement is restricted. For this reason, the contact 70 is always in a non-contact state with the spring cartridge 13 side, and no trouble occurs in the operation of the spring cartridge 13.
On the other hand, when measuring the compression amount of the spring cartridge 13, as shown in FIG. 13, the cap 69 is removed from the adapter 65, and the sensor holder 80 described below is attached instead of the cap 69. The sensor holder 80 is constituted by a cylinder body having a partition wall 80a at an intermediate position in the axial direction, and is attached to the adapter 65 side by screwing one end side thereof to the cylinder portion 66 of the adapter 65. A laser sensor 84 is attached to the other end side of the sensor holder 80 via a bracket 85.
An extension rod 81 is attached to the partition wall 80a of the sensor holder 80 so as to penetrate the partition wall 80a in the axial direction. One end of the extension bar 81 is screwed into the screw hole 73 at the other end of the contactor 70 to be connected to the contactor 70 and integrated therewith. On the other hand, a measuring body 82 is integrally provided on the other end side of the extension rod 81. A spring 83 is compressed between the measuring body 82 and the other end of the sensor holder 80, and the urging force of the spring 83 causes the extension rod 81 and the contactor 70 connected thereto to The contact body 71 of the contactor 70 is always pressed against and contacted with the top surface of the nut 16 or the end surface of the movable shaft 12.
Accordingly, in the state shown in FIG. 13, when the motor-operated valve is operated and the movable shaft 12 is displaced in the axial direction, the contactor 70 and the extension rod 81 move integrally following the displacement of the movable shaft 12. The amount of compression of the spring cartridge 13 is measured by the laser sensor 84 measuring the amount of displacement of the measuring body 82 using the laser light reflecting surface formed by the end face of the measuring body 82 as a measurement point. Can be measured continuously both when the motor-operated valve is closed and when it is opened.
Further, for example, in the sensor unit 30 shown in FIG. 3 or the laser sensor 34 provided in the sensor unit 40 shown in FIG. 4, the top surface of the nut 16 that is a measurement point by the laser sensor 34 is the valve. Since the grease of the body drive unit is present in the sealed portion, accurate measurement cannot be performed by the grease attached to the top surface of the nut 16. However, according to this structure, as shown in FIG. 13, the contactor 70 penetrates the end wall 65a of the adapter 65 in an oil-tight manner and extends to the outside thereof. Since the extension rod 81 provided with the measuring body 82 which becomes the measurement point of the laser sensor 34 is connected to the end portion, the measuring body 82 is not affected by the grease sealed on the valve body driving portion side. The position is measured by the laser sensor 34 without any problem, and a highly accurate measurement is realized.
Further, since the attachment and detachment of the sensor holder 80 is not accompanied by the attachment and detachment of the adapter 65, it is possible to prevent the leakage of the grease sealed on the valve body drive unit side when the sensor holder 80 is attached and detached. can do.
Note that the sensor unit 30 and the sensor unit 40 that are temporarily attached to the first and second motor-operated valve drive systems use the laser sensor 34 as a worm position measuring unit, and thus have a compact configuration. Therefore, it is possible to continuously obtain data continuously.
“Specific example of diagnostic method and apparatus for driving force of electric valve”
Subsequently, a diagnosis method and apparatus for applying the invention of the present application and performing diagnosis of the motor-operated valve, mainly related to torque, using the sensor unit 30 or other diagnostic data acquisition means such as a strain gauge will be described. .
First, the basic idea of the diagnostic method according to the present invention will be described. As described above, the sensor unit 30 is mounted at the time of diagnosis. The strain gauge 37 is permanently installed. The magnetic sensor 60 can be easily installed outside the motor-operated valve, and does not necessarily need to be installed permanently. It can be installed permanently or only at the time of diagnosis. Is assumed to be permanently installed in the conduit 61. Further, the strain gauges 51 and 52 arranged in the yoke 50 are permanently installed because there is no problem in the operation of the motor-operated valve even if they are permanently installed. On the other hand, the strain gauge 55 installed on the valve stem 1 may be caught when the valve stem 1 moves up and down in the axial direction along with the opening / closing operation of the valve if the strain gauge 55 is permanently installed. Here, as will be described later, there is a correlation between the valve stem stress and the yoke stress. Based on this correlation, the calculation is based on the yoke stress that can be always obtained by measurement, and the correlation is acquired. It is assumed that it is installed on the valve stem 1 only in some cases and is not installed otherwise.
By the way, it is not troublesome to acquire diagnostic data directly using the sensors for each diagnosis of each diagnostic item of the motorized valve, which is preferable from the viewpoint of improving the efficiency of the diagnostic work. I can not say. Therefore, in the diagnosis method of the present invention, although diagnostic data is acquired using each sensor or the like for the first time, a correlation between each data is obtained based on the first acquired data, and this is stored as a correlation database. From the next time, measure only data that can be obtained relatively easily, refer to the database, read other data corresponding to the measurement data, and perform diagnosis on the required diagnostic items based on the read data Thus, the efficiency of the diagnosis work is improved. Hereinafter, the diagnostic method and the like of the present invention will be specifically described based on some embodiments.
I: First embodiment
As shown in FIG. 1, the diagnostic method and apparatus of the first embodiment does not have a strain gauge on the spring cartridge 13 side, and a cap 38 is attached to the axially outer end side of the spring cartridge 13 during normal operation. On the other hand, at the time of diagnosis of the motor-operated valve, instead of the cap 38, as shown in FIG. 3, the motor-operated valve having a configuration in which the sensor unit 30 is temporarily mounted is targeted. This embodiment corresponds to Aspect 1, Aspect 2, Aspect 3, Aspect 5 and Aspect 8 of the invention relating to the diagnostic method, and Aspect 9, Aspect 10, Aspect 11, Aspect 13 and Aspect 16 relating to the diagnostic device. is there.
That is, as shown in FIG. 14, there are roughly two diagnostic forms. One of them is a first diagnosis form in which a diagnosis relating to a driving force is performed using a yoke stress obtained by measurement and a first correlation database between the yoke stress and the driving force. The other one monitors the change state of the driving force transmission efficiency in the valve body driving unit based on the driving force input to the valve body driving unit and the driving force output from the valve body driving unit. It is a 2nd diagnostic form which reflects a state in the said 1st diagnostic form.
IA: First diagnostic form
First, in the first diagnosis mode, in this diagnosis mode, the correlation between the yoke stress and the driving force obtained from the compressed state of the spring cartridge 13 in both the opening operation and the closing operation of the motor-operated valve. Is stored as a first correlation database.
The first correlation database is acquired between correlated information values, and the yoke stress acting on the yoke 50 is the reaction force of the valve stem stress acting on the valve stem 1 and the valve body. It is grasped as a driving force output from the driving unit. The torque applied to the stem nut 2 is obtained as a product of the compression force of the spring cartridge 13 and the radial dimension of the worm wheel 4, and is correlated with the driving force (herein referred to as “torque”) and the yoke stress. Since the relationship is established, as shown in FIG. 15, a correlation curve L is set using torque and yoke stress as parameters, and this is used as the first correlation database.
Here, in this embodiment, since the strain gauge is not provided on the spring cartridge 13 side as described above, and the sensor unit 30 is provided, the compressive force during the opening operation is provided due to the structure of the sensor unit 30. Cannot be obtained by measurement. Therefore, the sensor unit 30 obtains the compression force and the compression amount when the spring cartridge 13 is closed and the compression amount when the spring cartridge 13 is opened. First, after obtaining the spring characteristics of the spring cartridge 13 based on the compression force and the compression amount during the closing operation, the compression force corresponding to the compression amount during the opening operation is further read out from the spring characteristics. Thus, the compression force in both the opening operation and the closing operation is obtained, and the driving force is obtained and held by calculation based on the compression force.
In this case, a dimensional tolerance, that is, “backlash” is inevitably generated between the axial length of the spring cartridge 13 and the distance between both end surfaces of the spring cartridge housing portion on the valve body driving portion side. Therefore, when the compression amount of the spring cartridge 13 is measured, an accurate compression amount cannot be obtained unless the compression amount is obtained in a state where the backlash amount is removed. As a result, the reliability of the first correlation database itself is not obtained. Will not be secured. Therefore, in this embodiment, the invention according to claim 8 is applied to perform “backlash processing” in the process of acquiring the driving force to obtain an accurate compression amount, and the drive based on the accurate compression amount. Try to get power. This “backlash processing” will be described later.
After acquiring and holding the first correlation database in this way, the yoke as a driving force output signal from the valve body drive unit that can be always easily measured from the outside of the motor-operated valve in the subsequent diagnosis Only the stress is acquired by measurement, and the torque corresponding to the yoke stress (yoke stress “σ” in FIG. 15) acquired by measurement with reference to the first interphase database (torque “T” in FIG. 15). , And a diagnosis relating to the driving force of the motor-operated valve is performed based on the read torque.
The yoke stress is acquired by the strain gauges 51 and 52 disposed in the yoke 50 as shown in FIG. In this case, in this embodiment, the mounting positions of the strain gauges 51 and 52 with respect to the yoke 50 are set as follows. That is, as described above, the yoke 50 is between the lower flange portion 56 that is abutted and fastened to the valve box 61 side and the upper flange portion 57 that is abutted and fastened to the valve body drive portion 62 side. The valve stem 1 has a bifurcated shape including a pair of left and right support columns 53 and 54 disposed across the pair, and the valve rod 1 is disposed in a vertically penetrating manner at an intermediate position between the pair of support columns 53 and 54. .
And the strain gauges 51 and 52 are each affixed in the inner center position of the pair of support columns 51 and 52 of the yoke 50, respectively. It has been confirmed by experiments of the present applicant that the inner positions of the respective struts 53 and 54 to which the strain gauges 51 and 52 are affixed are portions where the amount of strain is large and stably generated in the yoke 50. . Therefore, by arranging the strain gauges 51 and 52 at such positions, the yoke stress obtained by measurement using the strain gauges 51 and 52 is highly reliable, and the first correlation is obtained. With reference to the database, the torque read in correspondence with the yoke stress is also highly reliable, and as a result, the accuracy and reliability of the diagnosis result of the motor-operated valve are further improved.
FIG. 41 shows a layout of the yoke stress sensor (strain gauge) on the yoke when the yoke stress distribution confirmation experiment is performed on the yoke. Here, the sensor “1” is disposed on the valve stem and directly measures the valve stem stress. The sensors “2” and “5” are arranged near the center of the outer side of the yoke. Sensors “3” and “4” are arranged closer to the inner center of the yoke. Sensor “6” is located outside the upper shoulder of the yoke. Sensor “7” is located on the outer surface of the lower shoulder of the yoke. Sensor “8” is disposed on the side of the lower shoulder of the yoke.
The measurement data of the yoke stress by each of these sensors is shown in FIGS. 42 and 43, respectively. From these data, it can be confirmed that among these sensors, the output (distortion amount) of the sensor 3 and the sensor 4 is the largest and stably generated. Based on such experimental results, in this embodiment, as described above, the strain gauges 51 and 52 are respectively arranged at positions closer to the inside center of the pair of columns 51 and 52 of the yoke 50.
Further, the strain gauges 51 and 52 are respectively arranged at symmetrical positions with the valve stem axis portion in the yoke 50 interposed therebetween, and the average value of the output values of the strain gauges 51 and 52 is determined as the yoke stress. Like to get as. With this configuration, the reliability of the measured value of the yoke stress itself measured by each of the strain gauges 51 and 52 is further enhanced, and further, the accuracy and reliability of the diagnosis result of the motor-operated valve is further increased. Improvement can be expected.
In this case, it cannot be denied that there is a slight variation in output characteristics between individual strain gauges due to manufacturing tolerances. Therefore, it is desirable that the strain gauges 51 and 52 to be attached as a pair to the yoke 59 of the same motor-operated valve are selected from those having similar output characteristics, and the above-described effects, that is, The reliability of the measured value of the yoke stress is further improved by acquiring the average value of the output values of the strain gauges 51 and 52 as the yoke stress.
Further, it is preferable to use a strain gauge having a structure in which a metal flange is attached to the sensitive element portion. In the strain gauge having such a structure, when the strain gauge is attached to the yoke 50 of the electric valve, the flange portion can be welded to the surface of the yoke 50 by spot welding. For example, the strain gauge is attached to the yoke 50 with an adhesive. There is no need to pause the next work (diagnostic data measurement by opening / closing the valve) until the adhesive is solidified and the adhesive strength is ensured, as in the case of sticking to the surface of the metal. Strain gauge installation can be completed in time, and a plurality of strain gauges can be installed almost simultaneously, which is extremely advantageous in terms of simplification of the strain gauge installation work and speeding up of the work. Since the strain gauge attached to the yoke 50 is often exposed to moisture such as rain water, it is desirable to use a waterproof type with a sensitive element completely molded.
According to the first diagnostic form, the first correlation database is held as a database (see FIG. 15) indicating the correlation between the yoke stress acting on the yoke and the torque obtained from the compression force of the spring cartridge 13. Then, referring to the first correlation database, the torque (torque “T” in FIG. 15) corresponding to the yoke stress (yoke stress “σ” in FIG. 15) acquired by measurement is read out. Thus, in the subsequent diagnosis, if only the yoke stress is obtained by measurement, the torque obtained from the compression force of the spring cartridge 13 is read with reference to the first correlation database, and the motor-operated valve Diagnosis regarding the driving force can be performed. For example, each time the diagnosis regarding the driving force of the motor-operated valve is performed, the compression force of the spring cartridge is Compared with the case of performing diagnosis acquires et determined torque, diagnostic work is extremely simple, and the said working can be performed with high workability, reduction in diagnosis cost is facilitated by much labor saving.
Further, in this case, the yoke stress is a stress acting on the yoke 50 exposed to the outside of the motor-operated valve, and can be measured from the outside of the motor-operated valve. Acquiring the stress corresponding to this, that is, the yoke stress, is, for example, much more work than when the stress is measured by opening a part of the motor-operated valve and attaching a strain gauge inside it. Therefore, it is possible to further improve the diagnostic workability and further reduce the diagnostic cost by saving labor.
Here, the “backlash processing” will be specifically described. As described above, the problem of obtaining the compression force during the opening operation based on the correlation data between the compression amount and the compression force during the closing operation and the compression amount during the opening operation is a problem of the spring cartridge 13. It is “backlash”.
That is, as described above, the compression amount of the spring cartridge 13 is not measured directly from both ends, but is integrated with the worm 5 by the laser sensor 34 in the sensor unit 30 as shown in FIG. A configuration is adopted in which the moving nut 16 is indirectly measured as the amount of movement in the worm axis direction. On the other hand, as shown in FIG. 1, the axial length of the spring cartridge 13 as a single unit is defined by the outer dimensions of the pair of washers 14 and 15 located at both ends of the disc springs 7 in the row direction. . Further, the spring cartridge 13 is restricted in movement in the direction of the arrow L when one washer 14 abuts against the stepped surface 21 of the large diameter hole portion 20 and the small diameter hole portion 19 of the casing, and the other washer 15. Is in contact with the end surface 36a of the core 36 disposed inside the adapter 31 that is abutted and fixed on the end surface 22 of the casing, thereby restricting movement in the direction of arrow R.
In this case, if the axial length of the spring cartridge 13 and the distance between the stepped surface 21 and the end surface 36a of the core 36 match, the amount of movement of the nut 16 is measured and the amount of compression of the spring cartridge 13 is measured. However, even if it is obtained as “Nut travel amount = spring cartridge compression amount”, the “spring cartridge compression amount” obtained indirectly by this nut movement amount is used as the “compression amount”. Does not occur.
However, as a matter of fact, the axial length of the spring cartridge 13 and the stepped surface due to the manufacturing tolerance of the spring cartridge 13 or the adapter 31, the assembly tolerance thereof, or the “sagging” of the packing 23, etc. A dimensional difference, that is, “backlash” inevitably occurs between the gap 21 and the gap dimension of the end surface 36 a of the core 36. Therefore, in the state where this “backlash” exists, the movement amount (movement distance) of the nut does not match the actual compression amount of the spring cartridge 13, and as a result, the movement amount of the nut 16 is measured. When the compression amount of the spring cartridge 13 is acquired and the acquired “deemed compression amount” is adopted as the “compression amount”, the following problems occur.
First, here is a general method for indirectly obtaining the compression amount of the spring cartridge 13 from the movement amount (movement distance) of the nut 16 when the electric valve is closed and further opened. explain.
FIG. 21 shows the spring cartridge 13 in a state before starting the closing operation of the electric valve. In a state before starting the closing operation of the motor-operated valve, the spring cartridge 13 is in a state of a tension load or less, and one washer 15 is in contact with the end surface 36 a of the core 36. At this time, the other washer 14 of the spring cartridge 13 is opposed to the stepped surface 21 with a backlash ΔL. The laser sensor 34 measures the distance [Ls1] from the end surface 22 to the nut 16 with the end surface 22 of the casing as a measurement reference position.
When the worm 5 moves in the closing operation direction from the state shown in FIG. 21, the movable shaft 12 moves integrally with the worm 5 in the arrow R direction as shown in FIG. 22, and the spring cartridge 13 is compressed. Is done. At this time, the laser sensor 34 measures the distance [L1] from the end surface 22 to the nut 16 with the end surface 22 of the casing as a measurement reference position. Therefore, the compression amount when the spring cartridge 13 is closed is obtained as “Ls1−L1”.
On the other hand, FIG. 23 shows the spring cartridge 13 in a state before the opening operation of the electric valve is started. In the state before the opening operation of the motor-operated valve, the spring cartridge 13 is in a state below the tension load, and the other washer 14 is in contact with the stepped surface 21. At this time, one washer 15 of the spring cartridge 13 is opposed to the end surface 36a of the core 36 with a backlash ΔL. The laser sensor 34 measures the distance [Ls2] from the end surface 22 to the nut 16 with the end surface 22 of the casing as a measurement reference position.
When the worm 5 moves in the opening operation direction from the state shown in FIG. 23, as shown in FIG. 24, the movable shaft 12 moves in the direction of arrow L integrally with the worm 5, and the spring cartridge 13 is compressed. Is done. At this time, the laser sensor 34 measures the distance [L2] from the end surface 22 to the nut 16 with the end surface 22 of the casing as a measurement reference position. Therefore, the compression amount when the spring cartridge 13 is opened is obtained as “L2−Ls2”.
In this way, when the compression amount of the spring cartridge 13 is indirectly obtained as the movement amount (movement distance) of the nut 16, the position of the nut 16 shown in FIG. Moreover, it is necessary to perform the position of the nut 16 shown in FIG.
However, in general, when the same measurement object moves to both sides in the axial direction, there is a recognition that measurement is easy if the origin is set at a single position when measuring the movement amount (i.e., For example, when the spring cartridge 13 moves in the closing operation direction and the opening operation direction as in the above measurement example, the measurement in either of these operation directions is simple. Measurement is often performed using one position (for example, the position shown in FIG. 21) as the origin.
Here, if the spring cartridge 13 moves in the closing operation direction and the opening operation direction, if the measurement is performed with the position of the nut 16 shown in FIG. In the direction, there is no problem because there is no play in that direction. However, when the operation direction changes from the closed operation direction to the open operation direction and the open operation is performed, the measured value measured here is the backlash ΔL. (In the case of the above measurement example, the measured value to be acquired is “L2 + ΔL”), and the measured value at the time of the opening operation of the compression amount of the spring cartridge 13 has an error corresponding to the backlash ΔL. become.
Here, the state at the time of the action | operation of the spring cartridge 13 shown in FIGS. 21-24 was shown as a time series graph in FIG.
In FIG. 25, the first initial position, which is the reference position of the spring cartridge 13 during the closing operation, corresponds to the state shown in FIG. 21, and the end face position of the nut 16 in this state is the amount of movement in the closing operation direction. This is the starting point of measurement. The first measured value in FIG. 25 is the amount of movement of the nut 16 from the origin during the closing operation.
In FIG. 25, the second initial position, which is the reference position of the spring cartridge 13 during the opening operation, corresponds to the state shown in FIG. 23, and the end face position of the nut 16 in this state is the amount of movement in the opening operation direction. This is the starting point of measurement. And the 2nd measured value of FIG. 25 is the movement amount of the said nut 16 from the 2nd initial position which is the said origin at the time of opening operation | movement.
Accordingly, when the movement amount at the opening operation is viewed with the first initial position on the closing operation side as a reference, a graph is obtained in which the second measurement value is shifted in the opening operation direction by a movement amount corresponding to the backlash ΔL. For this reason, when measuring the amount of movement during the opening operation, if the origin is set to the same point as the origin during the closing operation, an error corresponding to the play ΔL will occur.
From these facts, when the sensor unit 30 is used to indirectly obtain the compression amount of the spring cartridge 13 from the movement amount of the nut 16 and use it for diagnosis related to the torque of the motor-operated valve, the reliability In order to obtain a high diagnosis result, it is necessary to consider the measurement method so that an actual compression amount that eliminates the influence of the “backlash ΔL” is obtained.
Here, in consideration of the operation state of the spring cartridge 13 shown in FIGS. 21 to 24 described above, the compression amount and the compression force during the closing operation are referred to FIGS. 16 to 20 while corresponding to these. Based on the correlation data and the compression amount at the time of opening operation, a specific method and points to be noted when acquiring the compression force at the time of opening operation will be described.
First, as shown in FIG. 16, correlation data of “yoke stress-torque (value obtained by converting the compression force of the spring cartridge)” during the closing operation is obtained. Further, a torque curve L1 is obtained as correlation data of “compression amount−torque” during the closing operation as shown in FIG. Then, the torque curve L1 during the closing operation is moved point-symmetrically from the origin P to obtain the torque curve L2 during the opening operation.
Next, correlation data of “yoke stress-compression amount” at the time of opening operation as shown in FIG. 18 is acquired. Then, the compression amount “W1” of the spring cartridge 13 corresponding to the yoke stress “σ1” at the time of opening operation obtained by actual measurement based on the correlation data of “yoke stress-compression amount” at the time of opening operation of FIG. Ask for. Thereafter, based on FIG. 19 (which is the same as FIG. 17 but given as a separate figure for convenience of explanation), the torque “T1” at the opening operation corresponding to the compression amount “W1” at the opening operation is obtained. Ask.
By the way, the play amount ΔW of the spring cartridge 13 is not taken into consideration in the compression amount “W1” at the time of opening operation obtained here. However, in practice, as described above, the play ΔL inevitably exists in the compression direction of the spring cartridge 13.
Accordingly, when the reference position of the spring cartridge at the closing operation is regarded as the reference position of the spring cartridge at the opening operation, the torque obtained from the compression force of the spring cartridge 13 at the opening operation is used as the compression amount and torque at the closing operation. If the play ΔL is not taken into consideration when obtaining based on this, a highly accurate diagnosis result cannot be obtained in the diagnosis of the motor-operated valve.
That is, as shown in FIGS. 25 and 21 to 24, when there is a backlash ΔL in the compression direction of the spring cartridge 13, the torque curve at the time of opening operation is more open than when there is no backlash ΔL. As described above, the operating direction is shifted by the amount of compression corresponding to the play ΔL. Accordingly, when the torque curve L2 at the time of opening operation shown in FIG. 19 (that is, the torque curve when there is no backlash ΔL) and the torque curve L3 at the time of opening operation when the backlash ΔL exists are obtained, as shown in FIG. Become.
That is, the torque curve L2 at the time of opening when there is no backlash ΔL is set point-symmetrically with respect to the origin P with respect to the torque curve L1 at the time of closing. However, when the play ΔL exists, the torque curve L3 during the opening operation is shifted from the torque curve L2 by the play ΔL toward the compression amount (−) side, and the origin is set as Q.
For this reason, for example, when the torque corresponding to the compression amount “W1” (value based on the origin P) during the opening operation is obtained based on the torque curve L3 in FIG. Taking “W1−ΔL” and obtaining the torque corresponding to this, “torque = Ta”. This torque “T” is an actual torque during the opening operation when the play ΔL exists.
On the other hand, for example, the reference position of the compression amount of the spring cartridge at the opening operation is not the origin Q but the origin P (if the reference position of the compression amount of the spring cartridge at the closing operation is set, the compression amount “Torque = Tb” is obtained as the torque corresponding to “W1”, and an error of “Tb−Ta” is generated in the read torque between the case where the origin P is the reference and the origin Q is the reference. become.
As described above, when the torque at the time of opening operation is acquired, the backlash ΔL of the spring cartridge 13 is taken into consideration, so that the actually acting torque can be acquired with high accuracy, and electric power can be obtained using this. By making a diagnosis regarding the torque of the valve, an extremely high-precision diagnosis becomes possible.
Based on the correlation data of the open side “compression amount—torque” and the open side “compression amount—yoke stress” thus obtained, a correlation database of the open side “yoke stress-torque” is acquired. And the said correlation database acquired in this way is used for the diagnosis regarding the torque at the time of opening operation | movement with the yoke stress acquired by measurement. Further, in the diagnosis relating to the torque during the closing operation, the correlation data of “yoke stress-torque” in FIG. 16 obtained by actual measurement is used.
IB: Second diagnostic form
As described above, the second diagnosis form is a change state of the driving force transmission efficiency in the valve body driving unit based on the driving force input to the valve body driving unit and the driving force output from the valve body driving unit. This change state is reflected in the first diagnosis form described above.
First, “the driving force transmission efficiency in the valve body driving unit” is a ratio of the driving force input to the valve body driving unit side and the driving force output from the valve body driving unit side, and the driving force input signal and This can be grasped as a correlation of driving force output signals. Further, “monitoring of the change state of the driving force transmission efficiency” is to monitor the change state of the correlation continuously or in a spot manner as necessary. In this embodiment, the state is continuously monitored. Take the case as an example.
And the monitoring result of the change state of this driving force transmission efficiency is reflected in the diagnosis regarding the driving force of a motor operated valve. For example, if the driving force transmission efficiency changes to a predetermined change rate or more, or changes to a predetermined value or more, it is determined that the driving force transmission system is abnormal, and the driving force corresponds to the change rate or change amount. The driving force corresponding to the output signal is corrected to optimize the diagnosis regarding the driving force, and the deterioration tendency of the driving force transmission system is predicted and reflected in the maintenance plan. In this embodiment, as described below, since yoke stress is adopted as the driving force output from the valve body driving unit, the driving force transmission efficiency is not numerically known but is known as the rate of change. It is what you get.
Also, reflecting the changing state of driving force transmission efficiency,
a. Diagnosis of appropriateness of set torque, for example, diagnosis of appropriateness of torque value at the operation timing of the torque switch when the motorized valve is closed,
b. Diagnosis of appropriateness of the valve seat force, that is, diagnosis of appropriateness of the magnitude of the holding torque of the valve body when the motor-operated valve is closed,
c. Confirmation of margin of driving force, for example, confirmation of margin of driving force with respect to extraction torque at the time of pulling out the valve body that requires the maximum torque when the motorized valve is opened,
As a result, a total diagnosis of the driving force transmission system of the electric valve can be performed.
Hereinafter, the monitoring method of the change state of the driving force transmission efficiency and the diagnosis method when the monitoring result is reflected in the various diagnoses in the first diagnosis form will be described.
In FIG. 14, while the yoke stress obtained by measurement by the strain gauges 51 and 52 is used as a driving force output signal from the valve body driving unit, a current value signal, a compression amount signal, and a compressing force signal are used as driving force input signals. One of the above is adopted. Here, among these or each output signal, the current value signal is adopted as the driving force input signal. This current value signal generates a voltage corresponding to the magnitude of the magnetism when the magnetism from the electric wire 62 housed in the conduit 61 is sensed by the magnetic sensor 60 (see FIG. 7). Therefore, the current value signal is not a direct driving force input signal. For this reason, for example, a correlation between the current value and the compression force of the spring cartridge 13 is obtained in advance, a driving force corresponding to the current value is obtained based on the correlation, and this is obtained as a valve body drive unit. Used as driving force input to
Then, the driving force input signal obtained from the current value signal is compared with the driving force output signal obtained based on the yoke stress, and the change state of the driving force transmission efficiency in the valve body driving unit is monitored.
FIG. 26 shows the correlation between the driving force output signal and the driving force input signal. In FIG. 26, the yoke stress that is the driving force output signal is referred to as “valve axial force”, and the current value signal that is the driving force input signal is simply referred to as “magnetic”. According to the correlation data of FIG. 26, the driving force transmission state in the valve body driving unit can be confirmed from the correspondence relationship between the driving force output signal and the driving force input signal. For example, if the correlation shown in FIG. 26 is a correlation when the driving force transmission efficiency is appropriate, then when the correlation is continuously obtained, for example, the correlation curve is , Driving when the first correlation database is changed so as to translate in the upward direction (in the direction of the arrow), that is, in the direction in which the magnetic signal increases, from the first correlation curve obtained when acquiring the first correlation database. It can be determined that the power transmission efficiency is low.
In addition, the position of the correlation curve in FIG. 26 has not changed (that is, the correlation itself between the driving force output signal and the driving force input signal has not changed), but the set torque value has changed in the decreasing direction. However, although the driving force transmission efficiency is not lowered, it can be determined that the setting of the torque switch is shifted.
FIG. 27 shows a raw waveform of an output signal of the strain gauges 51 and 52 for measuring a valve shaft force (ie, yoke stress) and an output signal of the magnetic sensor 60 as a current value sensor at the time of torque seat. ing. Based on FIG. 27, the correlation curve of FIG. 26 is obtained. And based on FIGS. 26 and 27 and the first correlation database,
a. Diagnosis of appropriateness of set torque, for example, diagnosis of appropriateness of torque value at the operation timing of the torque switch when the motorized valve is closed,
b. Diagnosis of appropriateness of the valve seat force, that is, diagnosis of appropriateness of the magnitude of the holding torque of the valve body when the motor-operated valve is closed,
Can do.
For example, in the diagnosis of the suitability of the set torque in the item [a], first, in FIG. 27, the valve shaft force (that is, the yoke stress) at the time when the magnetic signal disappears due to the stop of the motor power supply by the torque switch operation is obtained. Using this valve shaft force and the first correlation database, the present set torque is obtained and its suitability is diagnosed. Here, there is no problem when there is no change in the driving force transmission efficiency in the valve body drive unit, but when there is a change in the driving force transmission efficiency, the suitability diagnosis is made based on the set torque. Therefore, a highly accurate and reliable diagnosis cannot be performed. Therefore, the change state of the driving force transmission efficiency in the valve body driving unit is confirmed from the correlation of “valve axial force−magnetism” shown in FIG. 26, and the driving force transmission efficiency in the valve body driving unit is reduced (that is, If it is determined that the correlation curve obtained at the present time is moving in the positive direction of the Y-axis from the first correlation curve (that is, moving upward), the first correlation database corresponds to the amount of decrease. And the torque corresponding to the valve shaft force is read out based on the corrected first correlation database, and the propriety of the torque is diagnosed as a set torque. Therefore, since the suitability is diagnosed based on the accurate set torque reflecting the change in the driving force transmission efficiency in the valve body drive unit, a more accurate and reliable diagnosis is possible.
Here, the correction method will be described in detail. As shown in FIG. 26, for example, a correlation curve (only a part of which is obtained by this measurement) is obtained as the first correlation curve. If the magnetic signal at a specific valve axial force (f) is changed from the signal value “m1” to “m2”, the rate of change of the magnetic signal “m2 / m1” Is the correction coefficient, and the torque “(m2 / m1) × T” obtained by multiplying the correction coefficient “m2 / m1” by the torque “T” obtained from the first correlation database is used as the set torque. It is.
If the correlation between the magnetic signal and the output signal of the load cell 33 is used, the set torque can be obtained from the magnetic signal. However, as shown in FIG. 27, the valve axial force signal is different from the magnetic signal. Since the signal information is fine, it is preferable to obtain the set torque based on the valve shaft force as described above in terms of diagnostic accuracy.
On the other hand, in the diagnosis of the appropriateness of the valve seat force in the item “b”, first, in FIG. 27, the valve axial force (ie, yoke stress) at the time of the valve seat is obtained, and this valve axial force and the first correlation database are obtained. Is used to learn the current valve seat force and diagnose its suitability. Here, there is no problem when there is no change in the driving force transmission efficiency in the valve body drive unit, but when there is a change in the driving force transmission efficiency, the propriety of the propulsion is determined based on the valve seat force. With the diagnosis, a highly accurate and reliable diagnosis cannot be performed. Therefore, the change state of the driving force transmission efficiency in the valve body driving unit is confirmed from the correlation of “valve axial force−magnetism” shown in FIG. 26, and it is determined that the driving force transmission efficiency in the valve body driving unit is lowered. The first correlation database is corrected in accordance with the amount of decrease, and the valve seat force corresponding to the valve axial force is read based on the corrected first correlation database. Diagnose the appropriateness of the seat force. Accordingly, since the suitability is diagnosed based on the accurate valve seat force reflecting the change in the driving force transmission efficiency in the valve body drive unit, a more accurate and reliable diagnosis is possible.
FIG. 28 shows an output signal of the strain gauges 51 and 52 for measuring a valve axial force (ie, yoke stress) in the vicinity of when the valve body is pulled out, an output signal of the magnetic sensor 60 as a current value sensor, and as a reference. The raw waveforms of the output signals of the laser sensor 34 for measuring the compression amount of the spring cartridge 13 are shown. FIG. 29 shows the operating state of each part corresponding to the raw waveforms of the valve shaft force and spring compression force (measured by the strain gauge 35) in the vicinity of when the valve body is pulled out.
The margin of the driving force of the electric valve can be confirmed using FIG.
Confirmation of this driving force margin is important in terms of ensuring the reliability of the motor-operated valve. In other words, if the margin of the driving force is small, for example, when the pulling resistance of the valve body increases as the surface roughness of the valve body advances due to corrosion, it is difficult to open the valve. It is also possible to become.
Therefore, regarding the margin of the driving force, the monitoring of the change state of the driving force transmission efficiency is significant. That is, the degree of margin of the driving force is confirmed based on the valve shaft force corresponding to the measured yoke stress, and even if it is determined that there is a sufficient margin, this is based on the data on the output side of the driving force. This is a determination, and the driving force transmission efficiency in the valve body driving unit is not involved here. Therefore, for example, even if it is determined from the valve shaft force that the drive force has a sufficient margin, the drive force transmission efficiency actually decreases, and on the motor side, the valve shaft force and
This is because a driving force input signal equal to or higher than the driving force obtained from the first correlation database is required, and there is a case where the driving force margin is small.
Assuming such a case, the change state of the driving force transmission efficiency is monitored, and when the degree of change is a predetermined rate or more, it is determined that the driving force transmission system is abnormal, and the driving force transmission efficiency is determined. It is considered to be extremely effective to correct the first correlation database according to the change state or to correct the driving force value obtained by referring to the correlation database according to the change rate. Incidentally, the “change rate” of the driving force transmission efficiency here is a change in the curve shape of the “valve axial force-magnetic” correlation curve shown in FIG. 26, as is clear from the description of FIG. The movement rate (change rate) with respect to the first correlation curve when the entire correlation curve moves in the Y-axis direction due to the change in the driving force transmission efficiency, that is, the change in the correlation. Needless to say.
First, the valve shaft force (yoke stress) when the valve body is pulled out is obtained from FIG. Then, the torque corresponding to the obtained valve shaft force is read from the first correlation database and is set as “pull-out torque”. Then, by comparing this pull-out torque with the total torque inherently possessed by the motor-operated valve, it is confirmed how much torque (driving force) is available (the total torque minus the pull-out torque). . Here, there is no problem when there is no change in the driving force transmission efficiency in the valve body drive unit, but when there is a change in the driving force transmission efficiency, a margin of torque based on the pull-out torque. Therefore, it is impossible to make a highly accurate and reliable diagnosis. Therefore, the change state of the driving force transmission efficiency in the valve body driving unit is confirmed from the correlation of “valve axial force−magnetism” shown in FIG. 26, and it is determined that the driving force transmission efficiency in the valve body driving unit is lowered. The first correlation database is corrected in accordance with the amount of decrease, and the torque corresponding to the valve shaft force is read out based on the corrected first correlation database. By using the exact torque as the "pull-out torque" and using it for diagnosis, it is possible to make a more accurate and reliable diagnosis, and the valve body pull-out failure can be prevented without fail. It is possible to maintain the functions required for ensuring safety in nuclear power plants.
In addition to such a method for confirming the margin of driving force, by monitoring the change state of the waveform of the magnetic signal in FIG. 28, the change in driving force input to the valve body drive unit when the valve body is withdrawn. The state can be confirmed.
FIG. 30 specifically shows an example of a procedure for obtaining the first correlation database and the “magnetic-torque” correlation database and the time required for the work.
That is, first, in step 1, the restraining force on the motor-operated valve is released as a preliminary work of the diagnosis work. The reason why the restraining force on the motor-operated valve is released in this way is that it is necessary to attach a strain gauge in a state where there is no distortion in the yoke 50 and the like.
In step 2, the cartridge holder 45 attached to the valve body drive unit is removed so as to cover the outer end side of the spring cartridge (abbreviated as TSC), and the sensor unit 30 attached in place of the cartridge holder 45 is attached. And the inner portions of the pair of left and right columns 53 and 54 of the yoke 50, which are the attachment portions of the strain gauges 51 and 52 as the yoke stress sensor, are respectively cleaned. This operation took about 10 minutes.
Next, in Step 3, the magnetic sensor 60 (indicated as a multi-element high-sensitivity magnetic sensor in FIG. 30) is attached to the conduit 61, and the sensor unit 30 (indicated as “shared torque sensor” in FIG. 30). The strain gauges 51 and 52 as yoke stress sensors are attached to the yoke 50.
In this case, the mounting positions of the magnetic sensor 60 and the sensor unit 30 are both upper parts of the motor-operated valve, whereas the mounting positions of the strain gauges 51 and 52 are middle parts of the motor-operated valve. Each part is spaced apart in the vertical direction. For this reason, the installation work of the magnetic sensor 60 and the sensor unit 30 to the upper part of the motor-operated valve and the installation work of the strain gauges 51 and 52 to the middle part of the motor-operated valve are subject to space constraints. However, a plurality of workers can be carried out in the form of simultaneous progress.For example, in the case of attaching a sensor to each of a yoke and a valve stem, which are adjacent parts of the motor-operated valve, from the viewpoint of work space, While the sensor mounting operation is being performed, a situation in which the other sensor cannot be mounted and a standby state does not occur, thereby speeding up the sensor mounting operation. In particular, the work of attaching the strain gauges 51 and 52 to the yoke 50 side can be completed in a very short time by using spot welding. This operation took about 15 minutes.
In step 4, the zero point adjustment is performed for each of the sensors constituted by the strain gauges. This operation took about 1 minute.
In step 5, the motor-operated valve is opened and closed, various data are collected using each sensor, and a correlation database of the first correlation database “magnetic-torque” of the motor-operated valve is acquired based on the collected data. To do. This diagnostic operation took about 11 minutes.
Finally, in step 6, recovery work such as removal of each sensor is performed, and all of the work is completed. This recovery process took about 15 minutes.
This work was completed in about 53 minutes, including the preliminary work and recovery work. In consideration of the fact that the work by the conventional method takes about 3 hours, it can be said that the work can be performed easily and quickly in an extremely short time. This shortening of the work time does not require opening of the electric box of the motor-operated valve when installing the sensor, the operation of mounting the magnetic sensor 60 and the sensor unit 30 on the upper part of the motor-operated valve, Attaching the strain gauges 51 and 52 to the middle part can be performed in the form of simultaneous progress without taking work waiting time, and attaching the strain gauge to the yoke can be performed in a very short time by spot welding, The place which depends on is big.
In the first diagnosis work, it is necessary to perform all the steps 1 to 6. However, in the subsequent diagnosis work, the sensor unit 30 and the strain gauge in step 1, step 2 and step 3 are used. 51 and 52 are not required, and if the magnetic sensor 60 in step 3 is also permanently installed, it is not necessary to perform the installation, and the operation in step 5 (valve axial force sensor and magnetic sensor data collection) is short. Perform time recovery work.
In the first and second diagnostic forms, the correlation between the driving force and the yoke stress and the diagnostic method based on the correlation between the yoke stress and the current value have been described. As a result, it is possible to diagnose the change in the driving force transmission status with time as follows. Hereinafter, a method for diagnosing a change with time in the driving force transmission state will be specifically described.
In FIG. 33, “current value” and “valve stem stress” in both the closed operation from the open state of the motorized valve and the open operation from the closed state are shown as examples of data actually acquired as a temporal change. , “Nut position (ie, worm position)”, “torque (spring cartridge compression force × r)” and “yoke stress” are shown. Various correlation databases are acquired by XY-converting any two of these measured data (determining the relationship between X and Y, where one is X and the other is Y). FIG. 34 is an enlarged view of the closing operation end portion in FIG.
Such a correlation database can be arbitrarily set between actually measured data elements, and here, as a correlation between data that can be a diagnostic element of a change over time such as a driving force transmission state of a motorized valve, 35, a correlation diagram of “compression amount-torque”, a correlation diagram of “valve stem stress-yoke stress” shown in FIG. 36, and “yoke stress (or valve stem stress) -torque (or compression amount) shown in FIG. ), Current value) ”and a correlation diagram of“ yoke stress (or valve stem stress) −torque (or compression amount), current integrated value ”shown in FIGS. 38 and 39.
According to the “compression amount—torque” correlation diagram (that is, the torque curve) shown in FIG. 35, it is possible to accurately diagnose the temporal change in the tension load of the spring cartridge 13. For example, as shown in FIG. 35, in the torque curve (1) acquired at the beginning of the installation of the spring cartridge 13 and the torque curve (2) acquired after the lapse of a predetermined period, the tension load decreases and the torque is changed accordingly. It can be grasped at a glance that the torque curve (2) changes to the low torque side with respect to the curve (1). As a cause of the decrease change of the tension load, for example, deterioration (wearing, etc.) of the disc spring constituting the spring cartridge 13 is considered, and the time-dependent change of the disc spring is advanced by the degree of decrease of the tension load. The disc spring replacement time is approaching, and the disc spring replacement time can be predicted by managing the tendency of the decrease in the tension load obtained every predetermined period.
In this case, a method of continuously acquiring the change state of the tension load of the spring cartridge 13 and monitoring the change tendency to know the change over time of the disc spring of the spring cartridge 13 and predict the replacement time. However, the prediction method based on the change over time is not limited to the change over time of the disc spring, and can be widely applied to various elements related to the diagnostic items related to the driving force of the motor-operated valve. In addition, by grasping changes in torque curves, changes in motor current values, changes in yoke stress, etc., it is possible to predict the maintenance time associated with changes over time in the drive train, wear and deformation of valve bodies and valve stems, etc. It is extremely effective in that the replacement timing can be predicted by, for example, ensuring stable and reliable operation of the motor-operated valve over a long period of time.
From the correlation diagram of “valve rod stress−yoke stress” shown in FIG. 36, for example, it is possible to diagnose the malfunction of the drive mechanism or the presence or absence of deviation of the set value of the set torque of the spring cartridge 13. For example, as shown in FIG. 36, the correlation curve (1) in the normal state acquired at the beginning of the installation of the spring cartridge 13 and the correlation curve (2) acquired after a predetermined period from the installation are compared. If the curve length of 2) is shorter than that of the correlation curve (1) and it is recognized that the maximum stress of both the valve stem stress and the yoke stress is decreasing, one of the causes is the valve stem drive. A reduction in the force (the driving force actually transmitted from the worm side to the valve stem through the stem nut) can be considered. This decrease in the valve stem drive force is caused by a malfunction of the drive mechanism (for example, the friction resistance increases due to oil shortage in the stem nut portion, etc., and the transmission efficiency of the drive force on the worm side to the valve body side is reduced. Of the set torque of the spring cartridge 13 (that is, a shift of the set value toward the low torque side), the malfunction of the drive mechanism or the set value of the set torque. It is possible to accurately diagnose the presence or absence of deviation. Further, since each correlation curve is on the same straight line, it can be confirmed that the sensitivity characteristic of each sensor is normal with no change.
In the correlation diagram of “yoke stress (valve stem stress) -torque (TSC compression amount) / current value envelope shown in FIG. 37, the following diagnosis is possible (note that the yoke stress is linear with the valve stem stress). It is possible to read “yoke stress” as “valve stem stress.” Also, the torque is linearly correlated with the compression amount of the spring cartridge (abbreviated as TSC) above the tension load. Therefore, “torque” can be read as “compression amount of spring cartridge”).
That is, the torque curve when the operation of the electric valve is normal is (a-1), the current value envelope curve (the curve enveloping the peak of the current value) is (b-1), and the torque curve after a predetermined period has elapsed. Is (a-2) and the current value envelope curve is (b-2). Here, for example, while the torque curve is maintained as (a-1), the current value envelope curve changes from (b-1) to (b-2). Indicates that the current value on the motor side has changed to an increasing side than normal, and from this changing tendency, for example, proper torque transmission is performed from the worm part to the valve body side, The motor is in a situation where it is operating at a high load, and therefore, it can be diagnosed that some trouble has occurred from the worm portion to the motor side.
In contrast, for example, when the torque curve changes from (a-1) to (a-2), a larger torque is required for the same yoke stress than in the normal state. Show. Therefore, in this case, the transmission efficiency of the driving force on the worm side to the valve body side is reduced, for example, the frictional resistance is increased due to oil shortage in the stem nut portion, and the driving force transmission efficiency is reduced. It is assumed that
FIG. 38 shows a correlation diagram of “yoke stress (valve stem stress) −torque (TSC compression amount) / current value envelope” in FIG. 37, and “yoke stress (valve stem stress) −torque (TSC compression amount) / current integrated value”. FIG. 38 is an enlarged view of a portion of the Y-axis of the current integrated value curve (corresponding to FIG. 34 which is the closing operation end portion in FIG. 33). It is. Here, the torque curve when the operation of the motor-operated valve is normal is the curve (a-1), the current integrated value curve is the curve (b-1), and the torque curve after the lapse of a predetermined period is the curve (a-2). The current integrated value curve is the curve (b-2). According to this “yoke stress (valve stem stress) −torque (TSC compression amount) / current integrated value” correlation diagram, the current integrated value is displayed as the time integrated value of the current value. As a result, the abnormality on the motor side can be judged with higher accuracy.
By the way, as shown in FIG. 34, there is a method of diagnosing the torque setting value with the torque at the time of turning off the electric current as one of the diagnostic methods for the electric valve. That is, when the torque switch is activated, the motor current is turned off and the motor is stopped. As shown in FIG. 37, when diagnosing the torque at the time of turning off the current as the torque setting value, the “yoke stress− By using the correlation database of “torque”, the torque setting value can be diagnosed more easily based on the yoke stress, and the diagnosis work can be performed more easily and quickly than the diagnosis of the torque setting value that directly measures the compression force of the spring cartridge. And labor saving. In addition, in this case, the valve stem stress and the valve body cutoff force (valve seat force), which are the original functions of the valve, can be directly diagnosed by the yoke stress.
The reference value in the torque setting value (allowable value = reference value ± 10%) is calculated from various resistance forces, and the reference value = constant × valve stem stress = constant × (valve closing force + packing force + fluid Resistance).
II: Second embodiment
The diagnostic method and apparatus of the second embodiment correspond to aspect 1, aspect 2, aspect 3, aspect 5 and aspect 8 relating to the diagnostic method, and aspect 9, aspect 10, aspect 11, aspect 13 and aspect 16 relating to the diagnostic apparatus. Thus, as shown in FIG. 31, the first diagnosis form and the second diagnosis form are provided in the same manner as in the first embodiment.
II-A: First diagnostic form
In the first diagnostic form, the first correlation database between the yoke stress and the driving force is used, and the driving force corresponding to the yoke stress is read from the first correlation database only by measuring the yoke stress, and based on this. In this case, particularly in this embodiment, as shown in FIG. 2, a strain gauge 37 that has been calibrated (before the calibration deadline) is arranged on the spring cartridge 13 side. At the time of diagnosis, the compression force of the spring cartridge 13 is measured and acquired by both the closing operation and the opening operation at the time of diagnosis. The yoke stress is measured and acquired by the pair of strain gauges 51 and 52 both during the closing operation and during the opening operation.
In this diagnostic method, the correlation between the driving force and the yoke stress is obtained based on the measured compressive force during both the opening and closing operations and the yoke stress during both the opening and closing operations. This is acquired as a first correlation database. In the subsequent diagnosis, by acquiring only the yoke stress by measurement, the driving force corresponding to the acquired yoke stress is read out from the first correlation database, and based on the read driving force. It is possible to make a diagnosis regarding the driving force of the electric valve.
The above diagnosis regarding the driving force can be performed directly by the strain gauge 37 when the strain gauge 37 is within the calibration effective period. That is, as shown in FIG. 2, it can be performed in the same form as during normal operation, that is, with the cap 46 mounted on the outer end side in the axial direction of the spring cartridge 13. Therefore, it is possible to immediately shift to the diagnosis work without requiring any additional work from the normal operation, and if necessary, the diagnosis can be continuously performed during the normal operation. However, the strain gauge 37 cannot accurately diagnose after the calibration deadline.
Therefore, according to the diagnosis method of this embodiment, the driving force corresponding to the yoke stress obtained by measurement is read from the correlation database, and the motor-operated valve is diagnosed based on the read driving force. Therefore, for example, even when the strain gauge 37 that directly measures the driving force obtained from the compression force of the spring cartridge 13 for each diagnosis is after the calibration deadline, the strain gauges 51 and 52 perform the diagnosis with high accuracy. It is possible to reduce the diagnosis cost by labor saving.
By the way, in the actual operation of the motor-operated valve, the force actually acting on the valve stem is not necessarily in a fixed relationship with the driving force due to, for example, the generation of frictional force in the valve body driving unit. When oil shortage occurs, the actual force acting on the valve stem is smaller than when there is no oil shortage, even when driving with the specified driving force. As described above, it is insufficient in terms of diagnosing the force acting on the valve body and the valve stem to be diagnosed as the function of the electric valve. However, in the case of this embodiment, the stress corresponding to the valve stem stress can be known from the yoke stress obtained by measurement, and the torque can be directly known by the strain gauge 37 (within the calibration effective period). Therefore, the drive transmission mechanism can be diagnosed by comparing the valve stem stress with the torque, and as a result, the combined diagnosis with the driving force enables a total diagnosis of the motor-operated valve. .
Further, prior to the time for replacement of the pair of strain gauges 51 and 52 provided in the yoke 50 (that is, the calibration deadline), the strain for replacement is placed near the mounting position of the strain gauges 51 and 52. A gauge is attached, and the correlation between the output characteristics of the existing strain gauges 51 and 52 and the output characteristics of the replacement strain gauge is grasped, and the existing strain gauges 51 and 52 are changed to the replacement strain gauge. After the replacement, if the correlation is sequentially reflected in the output characteristics of the replacement strain gauge, the correlation database is obtained by the strain gauges 51 and 52 provided in the yoke 50. Accordingly, the strain gauge 37 provided on the spring cartridge 13 side can be calibrated.
The calibration of the strain gauge 37 provided on the spring cartridge 13 side is performed by the pair of strain gauges 51 and 52 provided on the yoke 50 as described above, as shown in FIG. In place of 46, the sensor unit 40 including the load cell 33 and the laser sensor 34 is attached, and the output value of the load cell 33 calibrated in advance and the output value of the strain gauge 37 are compared with each other. Can be calibrated by the load cell 33. In this case, since the load cell 33 is externally attached and the calibration is easy, the strain gauge 37 can be easily calibrated by using the calibrated load cell 33. For example, the strain gauge 37 Compared to the case where the motor is removed from the motor-operated valve and the calibration is performed, the calibration work can be simplified and speeded up.
Further, as shown in FIG. 5, a sensor unit 47 having only the laser sensor 34 instead of the cap 46 is temporarily attached to the axially outer end side of the spring cartridge 13 by the adapter 38. By measuring the amount of compression of the spring cartridge 13 by the laser sensor 34, a torque curve can be obtained from the correlation with the strain gauge 37. Therefore, for example, by permanently installing the sensor unit 47 and displaying a torque curve that is always acquired, it is possible to easily diagnose a change with time in the tension load of the spring cartridge 13.
Further, the laser sensor 34 merely measures the amount of compression of the spring cartridge 13, and therefore, if it has such a function, for example, a difference provided with a differential transformer instead of the laser sensor 34. It is also possible to use a dynamic position measuring mechanism. Furthermore, it goes without saying that, as the sensor unit 47, the sensor unit 40 having a configuration including a load cell 33 in addition to the laser sensor 34 as shown in FIG.
Furthermore, in this embodiment, if each correlation database is displayed by the display means, it is easy to judge each diagnosis item based on the correlation at the time of diagnosis of the motorized valve, and the motorized valve diagnosis work can be performed easily and quickly. It is possible to reduce the diagnostic cost by reducing the cost and labor.
II-B: Second diagnostic form
Similar to the second diagnosis mode in the first embodiment, the second diagnosis mode is based on the driving force input to the valve body driving unit and the driving force output from the valve body driving unit. The change state of the driving force transmission efficiency in the body drive unit is monitored, and this change state is reflected in the first diagnosis form described above.
Here, the monitoring method of the change state of the driving force transmission efficiency and the diagnostic method when the monitoring result is reflected in the various diagnoses in the first diagnosis form will be described.
In FIG. 31, the yoke stress obtained by measurement by the strain gauges 51 and 52 is used as a driving force output signal from the valve body drive unit, while a current value signal, a compression amount signal, and a compression force signal are used as driving force input signals. One of the above is adopted. Here, among these output signals, a current value signal is adopted as a driving force input signal. This current value signal generates a voltage corresponding to the magnitude of the magnetism when the magnetism from the electric wire 62 housed in the conduit 61 is sensed by the magnetic sensor 60 (see FIG. 7). Therefore, the current value signal is not a direct driving force input signal. For this reason, for example, a correlation between the current value and the compression force of the spring cartridge 13 is obtained in advance, a driving force corresponding to the current value is obtained based on the correlation, and this is obtained as a valve body drive unit. Used as driving force input to
Then, the driving force input signal obtained from the current value signal is compared with the driving force output signal obtained based on the yoke stress, and the change state of the driving force transmission efficiency in the valve body driving unit is monitored.
Note that the diagnostic contents based on the monitoring result of the change state of the driving force transmission efficiency and the reflection method to the first diagnostic form are shown in FIGS. 25 to 29 in the second diagnostic form of the first embodiment. Since it is the same as that described with reference to, the description is incorporated and the description here is omitted.
III: Third embodiment
The diagnosis method and apparatus according to the third embodiment correspond to aspects 1 to 5, and as shown in FIG. 32, the first diagnosis form and the second diagnosis are the same as in the first embodiment. In addition to having a form, a third diagnostic form is further provided. In the first diagnosis form, a diagnosis relating to driving force is performed using a first correlation database of yoke stress and driving force. In the second diagnosis mode, the change state of the driving force transmission efficiency in the valve body driving unit is continuously monitored based on the driving force input to the valve body driving unit and the yoke stress output from the valve body driving unit. This change state is reflected in the first diagnosis form. The contents of the first and second diagnostic forms are the same as in the case of the first embodiment.
On the other hand, in the third diagnosis mode, the valve stem stress acting on the valve stem 1 is obtained, and the driving force transmission efficiency in the valve body drive unit is determined based on the valve stem stress and the drive force input to the valve body drive unit. And the change state of the numerical value are monitored, and this change state is reflected in the first diagnosis form.
Further, the reason why the strain gauge is directly provided on the valve stem 1 and is not obtained by measurement but based on the correlation with the yoke stress is as follows.
First, since the valve stem stress is directly acting on the valve body and corresponds to the load actually applied to the valve body, diagnosis of the motor-operated valve is performed based on the value of the valve stem stress. Thus, extremely reliable diagnostic results can be obtained. Second, as shown in FIG. 6, the valve stem stress is usually measured by attaching a strain gauge 55 directly to the valve stem 1. Since the valve rod 1 moves up and down in the axial direction in accordance with the opening / closing operation of the valve body, the strain gauge 55 is permanently installed on the valve rod 1 to perform measurement every time the diagnosis work is performed. If the exposed portion of the valve stem is shorter than the up-and-down movement distance of the valve stem, the strain gauge 55 may bite into the valve body side packing portion, which may hinder the operation of the valve stem 1. There is a request to reduce the frequency of direct measurement of valve stem stress as much as possible. Is theoretically grasped as the reaction force of the valve stem stress, and has a very good correlation with the valve stem stress, and the yoke stress is a portion exposed to the outside of the motor-operated valve as shown in FIG. The strain gauges 51 and 52 can be easily attached and measured here, and even if the strain gauges 51 and 52 are permanently installed, there is no obstacle to the operation of the motor-operated valve.
Hereinafter, the contents of each diagnosis form will be specifically described with reference to FIG.
III-A: First diagnostic form
In the first diagnosis mode, first, the correlation between the yoke stress and the driving force obtained from the compression state of the spring cartridge 13 in both the opening operation and the closing operation of the motor-operated valve is obtained, and this is obtained. 1 as a correlation database.
The first correlation database is acquired between correlated information values, and the yoke stress acting on the yoke 50 is the reaction force of the valve stem stress acting on the valve stem 1 and the valve body. It is grasped as a driving force output from the driving unit. The torque applied to the stem nut 2 is obtained as the product of the compression force of the spring cartridge 13 and the radial dimension of the worm wheel 4, and there is a correlation between this driving force (herein referred to as “torque”) and the yoke stress. Therefore, as shown in FIG. 15, a correlation curve L is set using torque and yoke stress as parameters, and this is used as the first correlation database.
Here, in this embodiment, since the strain gauge is not provided on the spring cartridge 13 side as described above, and the sensor unit 30 is provided, the compressive force during the opening operation is provided due to the structure of the sensor unit 30. Cannot be obtained by measurement. Therefore, the sensor unit 30 obtains the compression force and the compression amount when the spring cartridge 13 is closed and the compression amount when the spring cartridge 13 is opened. First, after obtaining the spring characteristics of the spring cartridge 13 based on the compression force and the compression amount during the closing operation, the compression force corresponding to the compression amount during the opening operation is further read out from the spring characteristics. Thus, the compression force in both the opening operation and the closing operation is obtained, and the driving force is obtained and held by calculation based on the compression force.
In this case, a dimensional tolerance, that is, “backlash” is inevitably generated between the axial length of the spring cartridge 13 and the distance between both end surfaces of the spring cartridge housing portion on the valve body driving portion side. Therefore, when the compression amount of the spring cartridge 13 is measured, an accurate compression amount cannot be obtained unless the compression amount is obtained in a state where the backlash amount is removed. As a result, the reliability of the first correlation database itself is not obtained. Will not be secured. Therefore, in this embodiment, the invention according to claim 8 is applied to perform “backlash processing” in the process of acquiring the driving force to obtain an accurate compression amount, and the drive based on the accurate compression amount. Try to get power. This “backlash processing” is as described in the first embodiment.
After acquiring and holding the first correlation database in this way, the yoke as a driving force output signal from the valve body drive unit that can be always easily measured from the outside of the motor-operated valve in the subsequent diagnosis Only the stress is acquired by measurement, and the torque corresponding to the yoke stress (yoke stress “σ” in FIG. 15) acquired by measurement with reference to the first interphase database (torque “T” in FIG. 15). , And a diagnosis relating to the driving force of the motor-operated valve is performed based on the read torque.
The yoke stress is acquired by the strain gauges 51 and 52 disposed in the yoke 50 as shown in FIG. In this case, in this embodiment, the mounting positions of the strain gauges 51 and 52 with respect to the yoke 50 are set as follows. That is, as described above, the yoke 50 is between the lower flange portion 56 that is abutted and fastened to the valve box 61 side and the upper flange portion 57 that is abutted and fastened to the valve body drive portion 62 side. The valve stem 1 has a bifurcated shape including a pair of left and right support columns 53 and 54 disposed across the pair, and the valve rod 1 is disposed in a vertically penetrating manner at an intermediate position between the pair of support columns 53 and 54. .
And the strain gauges 51 and 52 are each affixed in the inner center position of the pair of support columns 51 and 52 of the yoke 50, respectively. It has been confirmed by experiments of the present applicant that the inner positions of the respective struts 53 and 54 to which the strain gauges 51 and 52 are affixed are portions where the amount of strain is large and stably generated in the yoke 50. . Therefore, by arranging the strain gauges 51 and 52 at such positions, the yoke stress obtained by measurement using the strain gauges 51 and 52 is highly reliable, and the first correlation is obtained. With reference to the database, the torque read in correspondence with the yoke stress is also highly reliable, and as a result, the accuracy and reliability of the diagnosis result of the motor-operated valve are further improved.
Further, the strain gauges 51 and 52 are respectively arranged at symmetrical positions with the valve stem axis portion in the yoke 50 interposed therebetween, and the average value of the output values of the strain gauges 51 and 52 is determined as the yoke stress. Like to get as. With this configuration, the reliability of the measured value of the yoke stress itself measured by each of the strain gauges 51 and 52 is further enhanced, and further, the accuracy and reliability of the diagnosis result of the motor-operated valve is further increased. Improvement can be expected.
In this case, it cannot be denied that there is a slight variation in output characteristics between individual strain gauges due to manufacturing tolerances. Therefore, it is desirable that the strain gauges 51 and 52 to be attached as a pair to the yoke 59 of the same motor-operated valve are selected from those having similar output characteristics, and the above-described effects, that is, The reliability of the measured value of the yoke stress is further improved by acquiring the average value of the output values of the strain gauges 51 and 52 as the yoke stress.
Further, it is preferable to use a strain gauge having a structure in which a metal flange is attached to the sensitive element portion. In the strain gauge having such a structure, when the strain gauge is attached to the yoke 50 of the electric valve, the flange portion can be welded to the surface of the yoke 50 by spot welding. For example, the strain gauge is attached to the yoke 50 with an adhesive. There is no need to suspend the next operation until the adhesive is solidified and the adhesive strength is ensured, as in the case of sticking to the surface of the material. The strain gauge can be attached almost simultaneously, which is extremely advantageous in terms of simplification of the strain gauge attaching work and speeding up of the work. Since the strain gauge attached to the yoke 50 is often exposed to moisture such as rain water, it is desirable to use a waterproof type with a sensitive element completely molded.
According to the first diagnostic form, the first correlation database is held as a database (see FIG. 15) indicating the correlation between the yoke stress acting on the yoke and the torque obtained from the compression force of the spring cartridge 13. Then, referring to the correlation database, by reading out the torque (torque “T” in FIG. 15) corresponding to the yoke stress (yoke stress “σ” in FIG. 15) acquired by measurement, In the subsequent diagnosis, if only the yoke stress is obtained by measurement, the torque obtained from the compression force of the spring cartridge 13 is read with reference to the first correlation database, and the driving force of the motor-operated valve is determined based on this torque. Diagnosis can be performed, for example, from the compression force of the spring cartridge for each diagnosis related to the driving force of the motorized valve. Compared with the case of performing diagnosis to get that torque, diagnostic work is extremely simple, and the said working can be performed with high workability, reduction in diagnosis cost is facilitated by much labor saving.
Further, in this case, the yoke stress is a stress acting on the yoke 50 exposed to the outside of the motor-operated valve, and can be measured from the outside of the motor-operated valve. Acquiring the stress corresponding to this, that is, the yoke stress, is, for example, much more work than when the stress is measured by opening a part of the motor-operated valve and attaching a strain gauge inside it. Therefore, it is possible to further improve the diagnostic workability and further reduce the diagnostic cost by saving labor.
III-B: Second diagnostic form
As described above, the second diagnosis form is a change state of the driving force transmission efficiency in the valve body driving unit based on the driving force input to the valve body driving unit and the driving force output from the valve body driving unit. This change state is reflected in the first diagnosis form described above.
That is, in FIG. 32, the yoke stress obtained by measurement by the strain gauges 51 and 52 is used as a driving force output signal from the valve body driving unit, while a current value signal and a compression amount signal are used as the driving force input signal. Any one of the compression force signals is employed. Here, among these output signals, a current value signal is adopted as a driving force input signal. This current value signal generates a voltage corresponding to the magnitude of the magnetism when the magnetism from the electric wire 62 housed in the conduit 61 is sensed by the magnetic sensor 60 (see FIG. 7). Therefore, the current value signal is not a direct driving force input signal. For this reason, for example, a correlation between the current value and the compression force of the spring cartridge 13 is obtained in advance, a driving force corresponding to the current value is obtained based on the correlation, and this is obtained as a valve body drive unit. Used as driving force input to
Then, the driving force input signal obtained from the current value signal is compared with the driving force output signal obtained based on the yoke stress, and the change state of the driving force transmission efficiency in the valve body driving unit is monitored, and the result is obtained. This is reflected in the first diagnosis form. This reflection technique is the same as that described in the section of the second diagnosis form in the first embodiment described above, and the description here is omitted by using the corresponding description.
III-C: Third diagnostic form
As described above, the third diagnosis form employs the valve stem stress as the driving force output from the valve body driving unit, and based on the driving force and the valve stem stress input to the valve body driving unit. The numerical value of the driving force transmission efficiency in the body driving unit and the change state of the numerical value are monitored, and this change state is reflected in the first diagnosis form described above.
Here, the basic idea and the like of the third diagnostic form will be described.
The third diagnostic form places the priority of the diagnosis on the valve stem stress, and the gist thereof is as follows.
Since the driving force output from a driving source such as a motor is transmitted to the valve stem via the valve body driving unit, if frictional force is generated in the valve body driving unit, it is input to the valve body driving unit. The driving force to be transmitted and the force transmitted from the valve body driving unit to the valve stem do not coincide with each other, resulting in a difference between the two. For example, if the stem nut portion runs out of oil and generates frictional force, the driving force transmission efficiency in the valve body drive unit (that is, the input to the valve body drive unit and the output from the valve body drive unit) Even if a specified driving force is input, the force actually acting on the valve stem is smaller than when no oil shortage occurs.
Therefore, in the third diagnosis mode, the force that is actually acting directly on the valve body, that is, the valve rod acting on the valve stem, which is an item to be diagnosed as the original function (such as the closing function) of the motor-operated valve. The stress is acquired.
In addition, since the magnitude of the valve stem stress can be determined numerically and accurately, for example, by determining the friction coefficient “μ” between the valve stem and the stem nut, whether or not this is within an appropriate range. Can be diagnosed with high accuracy. Therefore, based on this friction coefficient “μ”, a quantitative comparison diagnosis with a design value or the like related to the motor-operated valve is performed to determine whether the friction state (lubrication state) of the valve body drive unit is normal or abnormal. It can be determined quantitatively and easily. This is one of the reasons why the valve stem stress is used for diagnosis of the motor-operated valve.
Hereinafter, the contents of the third diagnosis mode will be described.
In FIG. 32, first, when the operation of the motor-operated valve to the fully closed side is possible, a known axial force measured by the valve stem stress sensor is applied to the valve stem 1 to obtain the valve stem stress and at that time. Measure and obtain the yoke stress. The correlation between the yoke stress and the valve stem stress is acquired and held as a second correlation database.
When the current driving force transmission efficiency in the valve body drive unit is to be acquired by executing this third diagnostic form, the strain stresses 51 and 52 are used to measure the yoke stress acting on the yoke 50. At the same time, the driving force input to the valve body drive unit is measured and acquired by, for example, the magnetic sensor 60 (see FIG. 7).
Thereafter, referring to the second correlation database, the valve stem stress corresponding to the yoke stress obtained by measurement is read, and the read valve stem stress and the driving force are compared, Check the driving force transmission efficiency.
The confirmed driving force transmission efficiency is reflected in the diagnosis in the first diagnosis form. This reflection technique is the same as that described in the section of the second diagnosis form in the first embodiment described above, and the description here is omitted by using the corresponding description.
Further, according to the third diagnosis mode, the valve stem stress is obtained numerically. Therefore, the appropriateness of the correlation between the driving force and the valve stem stress is determined by using the numerically obtained valve stem stress. This makes it possible to make a highly reliable diagnosis regarding the lubricity of the valve body drive unit. Moreover, in this case, instead of directly measuring and obtaining the valve stem stress, the second correlation database is used to obtain it based on the yoke stress that can be easily measured, thereby reducing diagnostic costs. And improving the reliability of diagnosis results.
That is, in this third diagnostic form, the valve stem stress is used for confirming the driving force transmission efficiency, but since the magnitude of this valve stem stress is obtained numerically, this valve stem stress is used. Thus, the friction coefficient “μ” in the valve body drive unit can be obtained numerically and accurately.
Specifically, the friction coefficient “μ” in the valve body drive unit of the motor-operated valve is calculated by the well-known friction coefficient calculation formula “= [A × (torque / valve stem stress) −B × d] / [d + C × (torque / (Valve stem stress)] d is a stem effective diameter, and A, B, and C are constants, but in this calculation formula, elements other than “torque / valve stem stress” are constant values. By determining the torque / valve stem stress ratio “torque / valve stem stress”, it is possible to obtain the friction coefficient “μ” of the valve body drive unit and diagnose its suitability. By performing a quantitative comparison diagnosis with a design value or the like, it is possible to quantitatively and easily determine whether the frictional state (lubricating state) of the valve body drive unit is normal or abnormal.
In a specific example, the value of “torque / valve stem stress” serves as a reference for determining the friction status (lubrication status), and when the value of “torque / valve stem stress” exceeds the allowable upper limit value, It is determined that the lubrication condition is abnormal. For example, when oil shortage occurs in the stem nut portion and the frictional resistance increases, the valve stem stress decreases even if the torque remains constant and does not change. Since the value tends to exceed the upper limit value, it is possible to determine an abnormality “out of oil” due to an abnormality in the friction state (lubrication state).
Note that FIG. 39 shows data of diagnosis results of appropriateness of the friction coefficient based on driving force (torque) and valve stem stress (valve stem thrust). In this diagnosis example, when the determination value of whether or not the friction coefficient is appropriate is “0.20 or less”, the diagnosis indicates that the friction coefficient is “0.12”, and the friction coefficient of the motor-operated valve is determined to be acceptable.

  It is sectional drawing which shows the drive part of the motor operated valve of the type which does not incorporate a torque sensor.   It is sectional drawing which shows the drive part of the electric valve of the type which incorporated the torque sensor.   It is sectional drawing which shows the state which attached the sensor unit temporarily to the motor operated valve shown in FIG.   It is sectional drawing which shows the state which attached the sensor unit temporarily to the motor operated valve shown in FIG.   It is sectional drawing which shows the state which attached only the laser sensor to the motor operated valve shown in FIG.   It is an enlarged view of the yoke part of a motor operated valve.   It is sectional drawing which shows the specific attachment method of the magnetic sensor with respect to a conduit tube.   It is VIII-VIII sectional drawing of FIG.   It is sectional drawing which shows the other structural example of the drive part of the motor operated valve of the type which incorporated the torque sensor.   It is a XX arrow line view of FIG.   It is sectional drawing which shows the state which attached the cap to the edge part of the drive part shown in FIG.   It is a XII-XII arrow line view of FIG.   It is sectional drawing which shows the state which attached the sensor holder to the edge part of the drive part shown in FIG.   It is a functional block diagram in the diagnostic method of the motor operated valve concerning a 1st embodiment of the present invention.   It is explanatory drawing of a correlation database.   It is a correlation database of yoke stress and torque.   It is a correlation database of compression amount and torque.   It is a correlation database of yoke stress and compression amount.   It is a correlation database of compression amount and torque.   It is a correlation database of compression amount and torque.   It is a schematic diagram which shows the state before the closing operation start of a spring cartridge.   It is a schematic diagram which shows the state in the closing operation | movement of a spring cartridge.   It is a schematic diagram which shows the state before the opening operation | movement start of a spring cartridge.   It is a schematic diagram which shows the state in open operation of a spring cartridge.   It is a time series graph which shows the time change of the worm position at the time of closing operation and opening operation of an electric valve.   It is a correlation data curve of “valve axial force-magnetism” among correlation data obtained by XY conversion of acquired data.   It is a raw waveform figure of a valve axial force signal and a magnetic signal at the time of a torque seat of an electric valve.   FIG. 6 is a raw waveform diagram of a valve shaft force signal, a spring compression amount signal, and a magnetic signal in the vicinity of when the valve body is pulled out of the motor-operated valve.   It is a raw waveform figure of a valve axial force signal and a spring compression force signal for explaining operational relations of each part of a motor operated valve near the time of valve body extraction of a motor operated valve.   It is a diagnostic work flowchart.   It is a functional block diagram in the diagnostic method of the motor operated valve which concerns on 2nd Embodiment of this invention.   It is a functional block diagram in the diagnostic method of the motor operated valve which concerns on 3rd Embodiment of this invention.   It is explanatory drawing of acquisition data.   FIG. 28 is an enlarged view of a closing operation end portion in FIG. 27.   Of the correlation data obtained by XY conversion of the acquired data, this is correlation data between the spring cartridge compression amount and the torque.   Of the correlation data obtained by XY conversion of the acquired data, this is correlation data between the valve stem stress and the yoke stress.   Of the correlation data obtained by XY conversion of the acquired data, this is correlation data of yoke stress (valve stem stress), torque (spring cartridge compression amount), and current value envelope.   Of the correlation data obtained by XY conversion of the acquired data, this is correlation data of yoke stress (valve stem stress), torque (spring cartridge compression amount), and current (integrated value).   FIG. 33 is an enlarged view of a part of a Y axis of the current integrated value curve of FIG. 32.   It is diagnostic data of the friction state of a stem (valve stem) and a stem nut.   It is a yoke stress sensor arrangement | positioning figure in the case of a distribution confirmation experiment of a yoke stress.   This is yoke strain distribution data.   This is yoke strain distribution data.

Explanation of symbols

1 ·· Valve stem 2 ·· Stem nut 3 · · Drive sleeve 4 · · Worm wheel 5 · · Worm 6 · · Motor shaft 7 · · Extension cylinder 8 · · Circumferential groove 9 · · Torque switch 10 · · Bearing 11 ..Nut 12 ..Movable shaft 13 ..Torque spring cartridge 14 ..Washer 15 ..Washer 16 ..Nut 17 ..Belleville spring 18 ..Torque limit sleeve 19 ..Small diameter hole 20 ..Large diameter hole Part 21 ..Shoulder part 22 of large-diameter hole part ..End face 23 of casing ..Packing 24 ..O-ring 25 ..O-ring 26 ..Nut 27 ..Slit 28 ..Slit 30 ..Sensor unit 31. -Adapter 32-Sensor holder 33-Load cell 34-Laser sensor 35-Strain gauge 36-Core 37-Strain gauge 38 ·· Adapter 39 · · Adapter 40 · · Sensor unit 41 · · Lead wire 42 · · Cartridge presser 43 · · Core 44 · · Signal wire 45 · · Cartridge presser 46 · · Cap 47 · · Sensor holder 48 · · Connector 50 ・ ・ Yoke 51 ・ ・ Strain gauge 52 ・ ・ Strain gauge 55 ・ ・ Strain gauge 60 ・ ・ Magnetic sensor 61 ・ ・ Conduit pipe 62 ・ ・ Electric wire 65 ・ ・ Adapter 66 ・ ・ Cylinder part 67 ・ ・ Shaft hole 68 ・· O ring 69 · · Cap 70 · · Contact 71 · · Contact body 72 · · C ring 73 · · Screw hole 75 · · Stopper 76 · · Pin 80 · · Sensor holder 81 · · Extension rod 82 · · Measurement Body 83 .. Spring 84 .. Laser sensor

Claims (16)

According to the valve body drive unit that opens and closes the valve body using the rotational drive force of the worm to which the rotational drive force is applied by the electric force, and the reaction force acting in the axial direction of the worm in the valve body drive unit An electric valve diagnosis method for diagnosing the driving force of an electric valve provided with a spring cartridge that expands and contracts,
A correlation between the driving force output signal from the valve drive unit and the driving force obtained from the compression state of the spring cartridge in both the opening operation and the closing operation of the motorized valve is held as a first correlation database.
While obtaining the correlation between the driving force input signal to the valve body driving unit and the driving force output signal, and monitoring the change state of the driving force transmission efficiency in the valve body driving unit based on the correlation,
The driving force corresponding to the driving force output signal acquired by measurement is read with reference to the first correlation database, and diagnosis relating to the driving force of the motor-operated valve is performed based on the driving force. Motorized valve diagnostic method. In claim 1,
A method for diagnosing a motor-operated valve, wherein a change state of driving force transmission efficiency is monitored and the changed state is reflected in calculation of a driving force corresponding to the driving force output signal. In claim 1,
The motor-driven valve diagnosis method, wherein the driving force output signal is a yoke stress acting on the yoke. In claim 3,
Possessing a second correlation database indicating a correlation between the valve stem stress acting on the valve stem as the driving force output signal and the yoke stress;
Based on the valve stem stress read corresponding to the yoke stress obtained by measurement with reference to the second correlation database and the driving force input signal obtained by measurement, the valve body drive unit A motor-driven valve diagnosis method characterized by monitoring a change state of driving force transmission efficiency. In claim 1, 2, 3 or 4,
The driving force input signal is a current value signal corresponding to the driving force, a compression amount signal corresponding to the compression amount of the spring cartridge, or a compression force signal corresponding to the compression force of the spring cartridge. Valve diagnosis method. In claim 5,
The driving force input signal is a current value signal corresponding to the driving force, and the current value signal is based on signal information output from a plurality of magnetic sensors attached to the outer surface of a conduit tube containing the electric wire. The motor-driven valve diagnostic method characterized by the above-mentioned. In claim 5,
The driving force input signal is a compression amount signal corresponding to the compression amount of the spring cartridge, and the compression amount signal is provided on an adapter fixed to the outer surface side of the motor-operated valve and is provided on the shaft end side of the spring cartridge. A motor-operated valve diagnosis method characterized in that it is acquired based on displacement information in an axial direction of a contactor that can be contacted / non-contacted and is displaced following the compression displacement of the spring cartridge in the contacted state. In claim 3 or 4,
While acquiring and holding the compression force and compression amount of the spring cartridge by measurement,
Acquire and retain the accurate compression amount in which the yoke stress and the backlash amount in the expansion / contraction direction of the spring cartridge are removed by calculation both during the opening operation and the closing operation of the motorized valve,
Obtaining the correlation between the driving force and the yoke stress in both the opening operation and the closing operation obtained from the retained compression amount and the compression force and the yoke stress as the first correlation database,
A motor-driven valve diagnostic method, wherein a driving force corresponding to a yoke stress obtained by measurement is read with reference to the first correlation database. According to the valve body drive unit that opens and closes the valve body using the rotational drive force of the worm to which the rotational drive force is applied by the electric force, and the reaction force acting in the axial direction of the worm in the valve body drive unit A motor-operated valve diagnostic device that performs a diagnosis on the driving force of a motor-operated valve including a spring cartridge that expands and contracts,
A first correlation database showing a correlation between a driving force output signal from the valve element driving unit and a driving force obtained from a compression state of the spring cartridge, both at the time of opening and closing of the electric valve;
Monitoring means for acquiring a correlation between the driving force input signal to the valve body driving unit and the driving force output signal, and monitoring a change state of the driving force transmission efficiency in the valve body driving unit based on the correlation;
Diagnostic means for reading out the driving force corresponding to the driving force output signal obtained by measurement with reference to the first correlation database and making a diagnosis on the driving force of the motor-operated valve based on the driving force; A motor-operated valve diagnostic device. In claim 9,
A motor-operated valve diagnosis apparatus comprising: a calculation unit that monitors a change state of driving force transmission efficiency and reflects the change state in calculation of a driving force corresponding to the driving force output signal. In claim 9,
A motor-operated valve diagnostic apparatus using yoke stress acting on a yoke as the driving force output signal. In claim 11,
A second correlation database showing a correlation between the valve stem stress acting on the valve stem as the driving force output signal, the yoke stress, and the valve stem stress;
Based on the valve stem stress read out corresponding to the yoke stress obtained by measurement with reference to the second correlation database, and the driving force input signal obtained by measurement, the valve body drive unit A motor-operated valve diagnostic apparatus comprising: monitoring means for monitoring a change state of driving force transmission efficiency. In claim 9, 10, 11 or 12,
As the driving force input signal, a current value signal corresponding to the driving force, a compression amount signal corresponding to the compression amount of the spring cartridge, or a compression force signal corresponding to the compression force of the spring cartridge is used. Diagnostic device. In claim 13,
A driving force input signal acquisition means for acquiring the current value signal as the driving force input signal based on signal information output from a plurality of magnetic sensors attached to the outer surface of a conduit containing the electric wire. A motor-operated valve diagnostic apparatus characterized by that. In claim 13,
The compression amount signal as the driving force input signal is provided in an adapter fixed to the outer surface side of the motor-operated valve, and can be contacted / non-contacted with the shaft end side of the spring cartridge. A motor-driven valve diagnostic apparatus comprising driving force input signal acquisition means for acquiring information based on displacement information in the axial direction of a contact that is displaced following the compression displacement. In claim 11 or 12,
First acquisition means for acquiring and holding the accurate compression amount in which the backlash amount in the expansion and contraction direction of the spring cartridge is removed by calculation by the yoke stress and measurement both at the time of opening and closing of the electric valve When,
Second acquisition means for acquiring and holding the compression force and the compression amount of the spring cartridge by measurement;
A first correlation database showing a correlation between the driving force and the yoke stress in both the opening operation and the closing operation, which are obtained from the retained compression amount, the compression force, and the yoke stress;
A motor-driven valve diagnosis device comprising driving force reading means for reading a driving force corresponding to a yoke stress acquired by measurement with reference to the first correlation database.

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