JP2023105648A - Electric valve control device and electric valve control program - Google Patents

Abstract

To easily retrieve a reference position (origin) specific to an electric valve.SOLUTION: An electric valve control device comprises: a rotation instruction unit for instructing an instruction angle to a stepping motor in such a manner that a step advances in a direction in which an axial motion is limited by a stop mechanism; a rotation detection unit for acquiring a sensed angle of a rotor from a sensor; a storage unit for holding the acquired sensed angle as record data; a stop detection unit for detecting a stop state of the rotor based on the acquired sensed angle; and an origin discrimination unit for repeating tracking of steps from a step, in which the stop state is detected, in the record data, determining whether or not a differential between a sensed angle in the step in which the stop state is detected and the sensed angle in the tracked step is greater than a predetermined value, and discriminating a step which is advanced from a step, in which the differential is greater than the predetermined value, in an advancing direction by a predetermined number as an origin of rotation of the rotor.SELECTED DRAWING: Figure 11

Description

TECHNICAL FIELD The present invention relates to an electrically operated valve, and more particularly to a rotor control method.

An automobile air conditioner is generally configured by arranging a compressor, a condenser, an expansion device, an evaporator, etc. in a refrigeration cycle. A refrigerating cycle is provided with various control valves, such as an expansion valve as an expansion device, for controlling the flow of refrigerant. 2. Description of the Related Art With the recent spread of electric vehicles and the like, electrically operated valves having a motor as a drive unit are being widely used.

As such an electric valve, there is known one that includes a magnetic sensor for detecting the degree of opening of the valve (see Patent Document 1, for example). A valve body is provided at one end of an operating rod that rotates with the rotor, and a magnet (sensor magnet) is provided at the other end. A magnetic sensor is provided so as to face the sensor magnet in the axial direction. Rotational motion of the rotor is converted into axial motion of the valve body by the screw feed mechanism. By capturing the change in magnetic flux accompanying the rotation of the rotor with a magnetic sensor, the rotation angle of the sensor magnet and thus the axial position of the valve body can be detected, and the valve opening can be calculated.

A reference position, which serves as a control reference, is set for the valve body that moves up and down in the electric valve. When the rotor continues to rotate in the valve closing direction and reaches a reference position, which is also called an "origin", the rotation of the rotor is restricted by a stopper (see Patent Document 2, for example).

Even with the same type of electric valve, individual differences occur in the reference position. It is not appropriate to uniformly set the reference position for each motor operated valve. Therefore, when manufacturing the motor-operated valve, it is necessary to detect and record a unique reference position for each motor-operated valve.

Japanese Patent Application Laid-Open No. 2018-135908 JP 2020-204344 A

When the rotor is restricted in rotation by the stopper, the back electromotive force of the stepping motor driving the rotor decreases. Therefore, it is conceivable to identify the reference position by searching for a point where the back electromotive force of the stepping motor changes significantly while rotating the rotor in the valve closing direction. At this time, when the rotor is rotated at high speed, a strong impact is applied to the stopper at the reference position, which is not preferable. On the other hand, when the rotor is rotated at a low speed, it becomes difficult to detect changes in the back electromotive force. Moreover, if the movement of the rotor is restricted by foreign matter such as metal scraps instead of the stopper, the reference position may be erroneously recognized.

A main object of the present invention is to provide a technique for appropriately searching for a reference position (origin) specific to an electrically operated valve.

An electric valve control device according to one aspect of the present invention includes a stepping motor that rotates a rotor, a first mechanism that converts the rotary motion of the rotor into axial motion of the valve body, and a second mechanism that limits the axial motion of the valve body. , a sensor that measures the angle of the rotor to obtain a sensed angle, and directs the stepping motor to the stepping motor to advance step by step in a direction in which the axial motion is limited by the second mechanism. a rotation detector that acquires the sensing angle of the rotor from the sensor for each step; a storage unit that holds the sensing angle acquired for each step as recorded data; a stop detection unit that detects a stop state of the rotor due to the limitation of the axial motion based on the acquired sensing angle; It is determined whether or not the difference between the sensing angle at the step where is detected and the sensing angle at the retroactive step is greater than a predetermined value, the step at which the difference is greater than the predetermined value is identified, and from the identified step in the traveling direction an origin determination unit that determines a step advanced by a predetermined number as the origin of rotation of the rotor.

A motor-operated valve control device according to another aspect of the present invention includes a stepping motor that rotates a rotor, a mechanism that converts the rotary motion of the rotor into axial motion of the valve body, and a sensor that measures the angle of the rotor to obtain a sensing angle. and a rotation instructing unit that instructs the stepping motor to indicate the indicated angle so as to advance one step at a time, and a rotation detecting unit that acquires the sensed angle of the rotor from the sensor for each step. , a storage unit that stores the sensing angle acquired for each step as recording data, and a step-out for detecting the rotor's out-of-step state due to the limitation of the axial motion based on the sensing angle acquired for each step. In the recorded data, the detection unit repeats the step backward from the step where the out-of-step state was detected, and the difference between the sensing angle at the step where the out-of-step state was detected and the sensing angle at the backward step is a predetermined value. a trigger position determination unit that determines whether or not the difference is greater than the predetermined value, specifies a step in which the difference is larger than a predetermined value, and determines a step advanced by a predetermined number in the traveling direction from the specified step as a step-out trigger position. .

An electric valve control program according to one aspect of the present invention includes a stepping motor that rotates a rotor, a first mechanism that converts the rotary motion of the rotor into axial motion of the valve body, and a second mechanism that limits the axial motion of the valve body. , a sensor for measuring the angle of the rotor to obtain a sensed angle; A function to indicate an indicated angle, a function to acquire the sensed angle of the rotor from the sensor for each step, a function to store the sensed angle acquired for each step as recorded data, and a function to acquire the sensed angle for each step. Based on the sensed angle, a function to detect the stopped state of the rotor due to the limitation of the axial motion, and the step where the stopped state is detected by repeating the step backward from the step where the stopped state is detected in the recorded data determines whether or not the difference between the sensing angle in the previous step and the sensing angle in the retroactive step is greater than a predetermined value, identifies a step in which the difference is greater than the predetermined value, and advances a predetermined number of steps in the traveling direction from the identified step as the origin of rotation of the rotor.

A motor-operated valve control program in another aspect of the present invention includes a stepping motor that rotates a rotor, a mechanism that changes the rotary motion of the rotor into axial motion of the valve body, and a sensor that measures the angle of the rotor to obtain a sensed angle. A function of instructing a stepping motor to indicate an angle so as to advance step by step to a computer that controls a motor-operated valve having a function of obtaining a sensed angle of a rotor from a sensor for each step; A function to store the sensing angle acquired for each step as recorded data, a function to detect a rotor out-of-step state due to axial motion limitation based on the sensing angle acquired for each step, and a function to record data. repeats the steps backward from the step where the out-of-step state was detected, and determines whether or not the difference between the sensing angle at the step where the out-of-step state was detected and the sensing angle at the backward step is greater than a predetermined value. and identifying a step in which the difference is larger than a predetermined value, and determining a step advanced by a predetermined number in the traveling direction from the identified step as a step-out trigger position.

A motor-operated valve control device according to another aspect of the present invention includes a stepping motor that rotates a rotor, a first mechanism that converts the rotary motion of the rotor into axial motion of the valve body, and a second mechanism that limits the axial motion of the valve body. and a sensor that measures the angle of the rotor to obtain a sensed angle, and directs the stepper motor to advance step by step in a direction in which the axial motion is limited by the second mechanism. A rotation instructing unit for instructing an angle, a rotation detecting unit for acquiring the sensing angle of the rotor from the sensor for each step, a storage unit for holding the sensing angle acquired for each step as recorded data, and one step. A stop detection unit that detects the stop state of the rotor due to the limitation of the axial motion based on the sensed angle acquired every time. It is determined whether or not the difference between the sensing angle at the selected step and the sensing angle at the determination target step is equal to or less than a predetermined value. and an origin determination unit that determines the origin of rotation of the .

A motor-operated valve control device according to another aspect of the present invention includes a stepping motor that rotates a rotor, a mechanism that converts the rotary motion of the rotor into axial motion of the valve body, and a sensor that measures the angle of the rotor to obtain a sensing angle. and a rotation instructing unit that instructs the stepping motor to indicate the indicated angle so as to advance one step at a time, and a rotation detecting unit that acquires the sensed angle of the rotor from the sensor for each step. , a storage unit that stores the sensing angle acquired for each step as recording data, and a step-out for detecting the rotor's out-of-step state due to the limitation of the axial motion based on the sensing angle acquired for each step. The detection unit identifies a step to be determined in the order of progress of the steps in the recorded data, and the difference between the sensing angle at the step where the out-of-step state is detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. and a trigger position determination unit that determines whether or not the difference is equal to or less than a predetermined value, and determines the step to be determined first as a step-out trigger position.

A motor-operated valve control program according to another aspect of the present invention includes a stepping motor that rotates a rotor, a first mechanism that converts the rotary motion of the rotor into axial motion of the valve body, and a second mechanism that limits the axial motion of the valve body. and a sensor for measuring the angle of the rotor to obtain a sensed angle, a stepping motor to cause the computer controlling the motorized valve to advance step by step in the direction in which the axial motion is limited by the second mechanism. a function to indicate the indicated angle, a function to acquire the sensed angle of the rotor from the sensor for each step, a function to hold the acquired sensed angle as recorded data for each step, A function to detect the stopped state of the rotor due to the limitation of the axial motion based on the acquired detection angle, identify the step to be judged according to the progress order of the steps in the recorded data, and detect the step where the stopped state is detected. It is determined whether or not the difference between the angle and the sensed angle at the step to be determined is equal to or less than a predetermined value, and the step to be determined that is first determined to have the difference equal to or less than the predetermined value is set as the origin of rotation of the rotor. To demonstrate the ability to discriminate.

A motor-operated valve control program in another aspect of the present invention includes a stepping motor that rotates a rotor, a mechanism that changes the rotary motion of the rotor into axial motion of the valve body, and a sensor that measures the angle of the rotor to obtain a sensed angle. A function of instructing a stepping motor to indicate an angle so as to advance step by step to a computer that controls a motor-operated valve having a function of obtaining a sensed angle of a rotor from a sensor for each step; A function to store the sensing angle acquired for each step as recorded data, a function to detect a rotor out-of-step state due to axial motion limitation based on the sensing angle acquired for each step, and a function to record data. a step to be determined is identified according to the order of progress of the steps, and it is determined whether or not the difference between the sensing angle at the step where the out-of-step state was detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. and a function of discriminating the step to be determined for which the difference is first determined to be equal to or less than a predetermined value as the step-out trigger position.

ADVANTAGE OF THE INVENTION According to this invention, it becomes easy to search appropriately the reference position (origin) peculiar to a motor-operated valve.

1 is a cross-sectional view showing an electrically operated valve according to an embodiment; FIG. FIG. 2 is a diagram showing the configuration of a stator and its surroundings; It is a figure showing the structure of a rotor. FIG. 2 is a schematic diagram showing the relationship between a magnetic sensor, a sensor magnet, and magnetic lines of force generated from the sensor magnet; It is a top view of a sensor magnet. 4 is a graph showing the relationship between the sensor value of the sensor magnet and the sensing angle; 4 is a graph showing the relationship between an angle value (duty ratio) and steps. FIG. 4 is a schematic diagram of the movement range of the rotor; 4 is a graph showing transitions of steps and rotor angles in an origin detection operation; FIG. 10(A) is a graph showing transitions between steps and rotor angles in ideal behavior. FIG. 10(B) is a graph showing transitions between steps and rotor angles in realistic behavior. FIG. 11A is a graph for explaining a method of determining the origin on the premise of ideal behavior. FIG. 11B is a graph for explaining a method of determining the origin on the premise of realistic behavior. FIG. 12A is a graph showing an example in which the error range does not cross the boundary of angles. FIG. 12B is a graph showing an example in which the upper side of the error range straddles the angle boundary. FIG. 12C is a graph showing an example where the lower side of the error range straddles the boundary of the angle. It is a truth table for determining the inside and outside of the error range. It is a functional block diagram of an electric valve control device. 4 is a flow chart showing a main processing process;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for the sake of convenience, the positional relationship of each structure may be expressed based on the illustrated state. Also, in the following embodiments and modifications thereof, substantially the same constituent elements are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

FIG. 1 is a cross-sectional view showing an electrically operated valve according to an embodiment.
The motor-operated valve 1 is applied to a refrigerating cycle of an automotive air conditioner (not shown). This refrigeration cycle includes a compressor that compresses the circulating refrigerant, a condenser that condenses the compressed refrigerant, an expansion valve that throttles and expands the condensed refrigerant and delivers it in the form of mist, and an evaporator that evaporates the refrigerant in the form of mist. An evaporator or the like is provided to cool the air in the passenger compartment by the latent heat of evaporation. Motor operated valve 1 functions as an expansion valve for the refrigeration cycle.

A motor-operated valve 1 is configured by assembling a valve body 2 and a motor unit 3 . The valve main body 2 has a body 5 that accommodates a valve portion. The body 5 functions as a "valve body". The body 5 is configured by assembling a first body 6 and a second body 8 coaxially. Both the first body 6 and the second body 8 are made of stainless steel (hereinafter referred to as "SUS"). Since the valve seat 24 is provided in the second body 8, a material with excellent wear resistance is selected. The first body 6 has better weldability than the second body 8 , and the second body 8 has better workability than the first body 6 .

The first body 6 has a stepped cylindrical shape whose outer diameter gradually decreases downward. The outer diameter of the upper end portion of the first body 6 is slightly reduced, and a locking portion 52 is formed by a step. A male thread 10 is formed on the lower outer peripheral surface of the first body 6 for assembling the electric valve 1 to a piping body (not shown). A pipe extending from the condenser side, a pipe leading to the evaporator, and the like are connected to the pipe body, but the details thereof will not be described. A seal accommodating portion 12 consisting of an annular groove is formed on the outer peripheral surface of the first body 6 slightly above the male thread 10, and a seal ring 14 (O-ring) is fitted.

A circular hole-shaped concave fitting portion 16 is provided in the lower portion of the first body 6 . The second body 8 has a cylindrical shape with a bottom, and its upper portion is press-fitted into the concave fitting portion 16 . A seal accommodating portion 18 consisting of an annular groove is formed in the lower outer peripheral surface of the second body 8, and a seal ring 20 is fitted therein. A valve hole 22 is provided so as to axially penetrate the bottom of the second body 8 , and a valve seat 24 is formed at the upper end opening of the valve hole 22 . An inlet port 26 is provided at the side of the second body 8 and an outlet port 28 is provided at the bottom. A valve chamber 30 is formed inside the first body 6 and the second body 8 . The inlet port 26 and the outlet port 28 communicate through the valve chamber 30 .

An operating rod 32 extending from a rotor 60 of the motor unit 3 is inserted inside the body 5 . The operating rod 32 passes through the valve chamber 30 . The operating rod 32 is obtained by cutting a bar made of non-magnetic metal, and a needle-shaped valve element 34 is integrally provided in the lower part thereof. The valve portion is opened and closed by attaching and detaching the valve element 34 to and from the valve seat 24 from the valve chest 30 side.

A guide member 36 is erected at the center of the upper portion of the first body 6 . The guide member 36 is obtained by cutting a tubular member made of a non-magnetic metal into a stepped cylindrical shape, and has a male thread 38 formed on the outer peripheral surface of the central portion in the axial direction. The lower end portion of the guide member 36 has a large diameter, and the large diameter portion 40 is press-fitted into the upper center of the first body 6 and fixed coaxially. The guide member 36 slidably supports the operating rod 32 in the axial direction with its inner peripheral surface, and slidably supports the rotating shaft 62 of the rotor 60 with its outer peripheral surface.

A spring receiver 42 is provided on the operating rod 32 slightly above the valve body 34 , and a spring receiver 44 is also provided on the bottom of the guide member 36 . A spring 46 (functioning as a "biasing member") is interposed between the spring bearings 42 and 44 to bias the valve body 34 in the valve closing direction.

On the other hand, the motor unit 3 is configured as a three-phase stepping motor including a rotor 60 and a stator 64. As shown in FIG. The motor unit 3 has a cylindrical can 66 with a bottom, the rotor 60 is arranged inside the can 66, and the stator 64 is arranged outside. The can 66 is a bottomed cylindrical member that covers the space in which the valve element 34 and its drive mechanism are arranged and that contains the rotor 60. The can 66 acts as an inner pressure space (internal space) where the pressure of the refrigerant acts. and an outer non-pressure space (external space).

The can 66 is made of a non-magnetic metal (SUS in this embodiment), and is coaxially attached to the upper end of the first body 6 so that its lower portion is externally inserted. The amount of insertion of the can 66 is limited by locking the lower end of the can 66 with the locking portion 52 . The body 5 and the can 66 are fixed and sealed by all-around welding (not shown) along the boundary between the lower end of the can 66 and the first body 6 . A space surrounded by the body 5 and the can 66 forms the pressure space.

The stator 64 is configured by arranging a plurality of salient poles at regular intervals on the inner peripheral portion of the laminated core 70 . The laminated core 70 is configured by laminating annular cores in the axial direction. A bobbin 74 on which a coil 73 (electromagnetic coil) is mounted is attached to each salient pole. These coils 73 and bobbins 74 constitute a "coil unit 75". In this embodiment, three motor units 75 for supplying three-phase current are provided at intervals of 120 degrees with respect to the central axis of the laminated core 70 (details will be described later).

The stator 64 is provided integrally with the case 76 of the motor unit 3 . That is, the case 76 is obtained by injection molding (also referred to as “insert molding” or “molding”) of a corrosion-resistant resin material. The stator 64 is covered with molding resin obtained by injection molding. The case 76 is made of the molding resin. Hereinafter, the molded product of the stator 64 and the case 76 will also be referred to as a "stator unit 78".

The stator unit 78 has a hollow structure and is attached to the body 5 while coaxially passing through the can 66 . A seal accommodating portion 80 consisting of an annular groove is formed on the outer peripheral surface slightly below the locking portion 52 of the first body 6, and a seal ring 82 (O-ring) is fitted. A seal ring 82 is interposed between the upper outer peripheral surface of the first body 6 and the lower inner peripheral surface of the case 76 to prevent the outside atmosphere (such as water) from entering the gap between the can 66 and the stator 64. is prevented.

Rotor 60 includes a cylindrical rotor core 102 assembled to rotating shaft 62 , rotor magnets 104 provided on the outer peripheral surface of rotor core 102 , and sensor magnets 106 provided on the upper end surface of rotor core 102 . The rotor core 102 is attached to the rotating shaft 62 . The rotor magnet 104 is magnetized (magnetized) with a plurality of poles in its circumferential direction. The sensor magnet 106 is also magnetized (magnetized) with multiple poles. The rotor magnet 104 and the sensor magnet 106 are obtained by magnetizing a magnet portion integrally molded with the rotor core 102 in a post-process, the details of which will be described later.

The rotating shaft 62 is a bottomed cylindrical shaft, and is fitted around the guide member 36 with its open end facing downward. A female thread 108 is formed on the lower inner peripheral surface of the rotating shaft 62 and meshes with the male thread 38 of the guide member 36 . Rotational motion of the rotor 60 is converted into axial motion of the operating rod 32 by the screw feed mechanism 109 using these threaded portions. As a result, the valve element 34 is moved (lifted/lowered) in the axial direction, that is, in the opening/closing direction of the valve portion. The screw feed mechanism 109 is an example of "a first mechanism that changes the rotational motion of the rotor 60 into the axial motion of the valve element 34".

The diameter of the upper portion of the operating rod 32 is reduced, and the reduced diameter portion 110 penetrates the bottom portion 112 of the rotating shaft 62 . An annular stopper 114 is fixed to the distal end of the reduced diameter portion 110 . On the other hand, a spring 116 is interposed between the base end of the diameter-reduced portion 110 and the bottom portion 112 to urge the operating rod 32 downward (that is, in the valve closing direction). With such a configuration, when the valve is opened, the operating rod 32 is displaced integrally with the rotor 60 in such a manner that the stopper 114 is locked to the bottom portion 112 . On the other hand, when the valve is closed, the spring 116 is compressed by the reaction force that the valve element 34 receives from the valve seat 24 . The valve element 34 can be pressed against the valve seat 24 by the elastic reaction force of the spring 116 at this time, and the seating performance (valve closing performance) of the valve element 34 can be enhanced.

The motor unit 3 has a circuit board 118 outside the can 66 . The circuit board 118 is fixed inside the case 76 . In this embodiment, various circuits functioning as a control section and a communication section are mounted on the lower surface of the circuit board 118 . Specifically, a drive circuit for driving the motor, a control circuit (microcomputer) that outputs control signals to the drive circuit, a communication circuit for the control circuit to communicate with an external device, each circuit and motor (coil) A power supply circuit and the like for supplying power are mounted. The upper end of the case 76 is closed with a lid 77 . A circuit board 118 is arranged in the space below the lid 77 in the case 76 .

A magnetic sensor 119 is provided on the surface of the circuit board 118 facing the sensor magnet 106 . The magnetic sensor 119 axially faces the sensor magnet 106 through the bottom end wall of the can 66 . The magnetic flux generated by the sensor magnet 106 changes as the rotor 60 rotates. The magnetic sensor 119 detects the amount of displacement of the rotor 60 (in this embodiment, the rotation angle of the rotor 60) by capturing this change in magnetic flux. Based on the displacement of the rotor 60, the control unit calculates the axial position of the valve body 34 and thus the valve opening degree.

A pair of terminals 117 connected to the coil 73 extends from each bobbin 74 and is connected to a circuit board 118 . A power supply terminal, a ground terminal, and a communication terminal (also collectively referred to as “connection terminals 81”) extend from the circuit board 118 and pass through the side wall of the case 76 to be drawn to the outside. A connector portion 79 is provided integrally with the side portion of the case 76 , and connection terminals 81 are arranged inside the connector portion 79 .

A stopper 90 is formed below the rotor 60 . As shown in Patent Document 2, the structure of the stopper 90 is known. When the operating rod 32 reaches the valve closing position, the spring 116 applies an elastic reaction force to the rotor 60 to keep the valve closed stably. Ultimately, the stopper 90 comes into contact with a protrusion (locking portion) (not shown) formed as a part of the guide member 36, thereby completely restricting the rotation of the rotor 60 in the valve closing direction. Hereinafter, the step when the stopper 90 comes into contact with the protrusion is referred to as the "origin" of the step. Further, in this embodiment, the valve body 34 is assumed to be at the "reference position" at the origin of the step.

FIG. 2 is a diagram showing the configuration of the stator 64 and its surroundings. FIG. 2A is a cross-sectional view of the stator unit 78 corresponding to the cross-section taken along line AA of FIG. FIG. 2B is a diagram showing only the stator 64 (state before resin molding). For reference, FIG. 2A shows the can 66 and the rotor 60 (see two-dot chain lines).

Since the motor unit 3 is a three-phase motor, the coil units 75 are provided around the axis L of the rotor 60 at regular intervals, as shown in FIG. 2(A). As shown in FIG. 2B, slots 120a to 120c (collectively referred to as "slots 120" when not distinguished) are formed in the inner peripheral portion of the laminated core 70 at intervals of 120 degrees with respect to the axis L. is provided. In each slot 120, salient poles 122a to 122c (generically referred to as "salient poles 122") projecting radially inward from the center thereof are formed. (collectively referred to as "coil 73") are assembled. A slit 124 having a U-shaped cross section is also formed between the slots 120 adjacent to each other to optimize the magnetic path.

The rotor magnet 104 faces the salient poles 122a to 122c via the can 66. As shown in FIG. In this embodiment, as shown in FIG. 2(A), the rotor magnet 104 is magnetized with 10 male-threaded poles, but the number of poles can be set appropriately.

Next, the configuration of the magnets in rotor 60 will be described in detail.
FIG. 3 is a diagram showing the configuration of the rotor 60. As shown in FIG. 3(A) is a perspective view, FIG. 3(B) is a front view, FIG. 3(C) is a plan view, and FIG. 3(D) is a cross-sectional view taken along line BB of FIG. 3(C). "N" in the figure indicates an N pole, and "S" indicates an S pole. For convenience of explanation, the illustration of the rotating shaft 62 (see FIG. 1) is omitted in FIG.

The rotor 60 has a rotor magnet 104 along the outer peripheral surface of the rotor core 102 and a sensor magnet 106 at the axial end of the rotor core 102 (FIGS. 3A and 3D). The rotor magnet 104 has a cylindrical shape and is magnetized with 10 poles on its outer peripheral surface (FIGS. 3(B) and 3(C)). On the other hand, the sensor magnet 106 has an annular shape and is magnetized with planar two poles.

As shown in FIG. 3D, the inner peripheral surface of the rotor magnet 104 is fitted in the annular groove 140, and the lower surface of the sensor magnet 106 is fitted in the annular groove 144. As shown in FIG. That is, the annular groove 140 functions as a drop-off prevention structure that prevents the rotor magnet 104 from dropping off from the rotor core 102 . Similarly, annular groove 144 functions as a drop-off prevention structure that prevents drop-off of sensor magnet 106 from rotor core 102 .

Based on the above configuration, a method for detecting the rotation angle of the rotor 60 by the magnetic sensor 119 will now be described. In addition, below, the up-down direction of FIG. 1 is called "opening-and-closing direction" or "up-down direction."

FIG. 4 is a schematic diagram showing the relationship between the magnetic sensor 119, the sensor magnet 106, and the lines of magnetic force generated from the sensor magnet 106. As shown in FIG.
FIG. 4 is a schematic diagram of the magnetic sensor 119 and the sensor magnet 106 viewed from the side. As shown in FIG. 4, magnetic lines of force are generated from N to S of the sensor magnet 106 (permanent magnet). A magnetic sensor 119 positioned directly above the sensor magnet 106 is a known rotary sensor that detects magnetic lines of force generated from the sensor magnet 106 . The magnetic sensor 119 detects the rotation angle of the sensor magnet 106 (rotor 60) based on the direction of the magnetic lines of force (details will be described later). In the present embodiment, the magnetic sensor 119 can detect the rotation angle of the sensor magnet 106. The magnetic sensor 119 directly detects the distance to the sensor magnet 106, in other words, the amount of movement of the operating rod 32 in the opening/closing direction. It is assumed that it cannot be detected.

FIG. 5 is a plan view of the sensor magnet 106. FIG.
Rotational driving force is applied to the rotor 60 by applying a driving current to the coils 73 of the stator 64 by a method described later. When the rotor 60 is rotated in the valve closing direction (downward direction) (hereinafter referred to as “downward rotation”), the operating rod 32 (valve element 34) moves in the valve closing direction, that is, in the drawing of FIG. Move down. When the rotor 60 is rotated in the valve-opening direction (hereinafter referred to as "upward rotation"), the operating rod 32 (valve element 34) moves in the valve-opening direction, that is, upward in FIG. .

As the rotor 60 rotates, the sensor magnet 106 also rotates. As the sensor magnet 106 rotates, the magnetic field direction MA of the sensor magnet 106 also changes. When the XY coordinate system (corresponding to the horizontal plane in FIG. 1) is set as shown in FIG. 5, the angle formed by the magnetic field direction MA with the X axis is assumed to be θ. The magnetic sensor 119 detects the rotation angle θ of the sensor magnet 106 by a known method shown in the angle sensor of Patent Document 1.

FIG. 6 is a graph showing the relationship between the sensor value of the sensor magnet 106 and the sensing angle.
The horizontal axis indicates the rotation angle θ of the sensor magnet 106 to be measured by the magnetic sensor 119 (hereinafter sometimes referred to as "sensing angle"). The vertical axis is the sensor value of the magnetic sensor 119 . The sensor values in this example are arctangent values. As shown in FIG. 6, the magnetic sensor 119 detects a sensor value showing a sawtooth waveform corresponding to the sensing angle. The magnetic sensor 119 replaces the sensor value, which is an analog signal, with a pulse duty ratio by PWM (Pulse Width Modulation), and outputs a current indicating a modulated digital signal. At this time, the duty ratio of the pulse is determined by normalizing the sensor value from "lower limit value DA to upper limit value TA". The lower limit value DA and the upper limit value TA can be set arbitrarily. The lower limit value DA may be zero. Hereinafter, the pulse duty ratio may be referred to as an "angle value". The control circuit can identify the actual rotor angle (perceived angle) based on the duty ratio (angle value) read from the pulse of the digital signal according to the specifications of the magnetic sensor 119 .

FIG. 7 is a graph showing the relationship between the angle value (duty ratio) and step.
In this embodiment, when moving the valve body 34 from the highest point to the lowest point, the rotor 60 rotates four times in total. Although details will be described later, the control circuit rotates the rotor 60 by changing the magnetic field direction of each coil 73 by changing the drive current supplied to the three-phase coils 73 . In this embodiment, the control circuit rotates the rotor 60 in units of u1 degrees (details will be described later). Hereinafter, this unit rotation amount will be referred to as a "step". From 360°×4 rotations÷u1°=1440/u1=SM4, the control circuit instructs the rotor 60 to rotate a total of 4 steps of SM within the operating range of the operating rod 32 . The angle value changes four times between DA and TA corresponding to four rotations of the rotor 60 .

Step 0 corresponds to the origin, and step n represents the nth step counted from the origin. SM1 shown in the figure represents the order of steps when the mechanical angle makes one revolution, SM2 represents the order of steps when the mechanical angle makes two revolutions, and SM3 represents the order of steps when the mechanical angle makes three revolutions. , and SM4 represents the order of steps when the mechanical angle rotates four times. A mechanical angle refers to an angle in real space of a rotating body such as the rotor 60 .

The control circuit supplies a predetermined level of drive current to the U-phase coil 73a. At this time, a drive current of a predetermined level is similarly applied to V-phase coil 73b and W-phase coil 73c. By applying a drive current to each coil 73, the magnetic field in the coil 73 is changed and the rotor 60 is rotated. A combination of current values of drive currents to be applied to each of U-phase coil 73a, V-phase coil 73b and W-phase coil 73c is called an "excitation pattern". There are N types of excitation patterns in this embodiment. Changing a certain excitation pattern P1 to an adjacent excitation pattern P2 corresponds to "one step" of rotation, in other words, a rotation instruction for a unit rotation amount.

By changing the excitation pattern, in other words, by changing the excitation pattern step by step, the indicated angle α (ideal rotor angle) is controlled. The rotor 60 rotates in synchronization with the change in the indicated angle α, and the sensing angle θ also changes. After changing the excitation pattern, by calculating the sensing angle θ from the angle value detected by the magnetic sensor 119, the control circuit can detect a state in which the sensing angle θ (actual rotor angle) follows the indicated angle α. It is determined whether or not. The state in which the sensing angle .theta.

A pattern ID is assigned to each of the N types of excitation patterns. IU(N1), IV (N1) and IW(N1). That is, the excitation pattern (N1) means a combination of [IU(N1), IV(N1), IW(N1)]. Drive currents IU(N1), IV(N1) and IW(N1) generate a magnetic field in each coil 73 to guide the rotor 60 to an indicated angle α corresponding to the excitation pattern (N1).

The N types of pattern IDs correspond to N steps for one round of the electrical angle. The electrical angle is a theoretical value obtained by evenly assigning N pattern IDs in the range of 0 to 360 degrees. Each step n from the origin to the top is cyclically associated with the pattern ID in sequence. For example, the pattern ID is defined as the remainder of n divided by N. A continuous pattern ID corresponds to an excitation pattern that changes continuously.

When the control circuit moves from step n to step n+1, it switches from excitation pattern (N1) to excitation pattern (N1+1). As a result, the magnetic field generated by each coil 73 is changed with the drive current values [IU(N1+1), IV(N1+1), IW(N1+1)], and the rotor 60 is rotated upward by the unit rotation amount. Conversely, when the control circuit moves from step n to step n-1, it switches from excitation pattern (N1) to excitation pattern (N1-1). As a result, the magnetic field generated by each coil 73 is changed by the drive current values [IU(N1-1), IV(N1-1), IW(N1-1)], and the rotor 60 is rotated downward by the unit rotation amount.

In the case of the rotor 60 having the structure shown in FIG. 3, since the rotor magnet 104 has five pairs of N and S poles, the rotor 60 rotates five times in one revolution (360 mechanical degrees). That is, one round of the electrical angle corresponds to 72 degrees of the mechanical angle. Also, since one revolution of the electrical angle includes N steps, the mechanical angle rotated by one step change is u1=72/N degrees. Further, as described with reference to FIG. 7, when the rotor 60 is rotated four times while the valve body 34 is moved from the highest point to the origin, 4.times.5.times.N steps are advanced in the movement over the entire area. become. That is, SM4 shown in FIG. 7 is 4×5×N. Similarly, SM1 is 5*N, SM2 is 2*5*N, and SM3 is 3*5*N.

In this embodiment, the position of the rotor 60 when the stopper 90 contacts the guide member 36 (more precisely, the projection of the guide member 36) is defined as the origin (reference position), and the control circuit controls the angle value and The excitation pattern is recorded as "origin information (reference information)". When the motor-operated valve 1 is manufactured, origin information (reference information) unique to the motor-operated valve 1 is recorded in the non-volatile memory of the circuit board 118 . Then, the control circuit adjusts the amount of movement of the operating rod 32, that is, the valve opening degree of the motor-operated valve 1, by step n based on the origin (valve closed position).

FIG. 8 is a schematic diagram of the movement range of the rotor 60. As shown in FIG.
The right direction in FIG. 8 indicates the valve opening direction (upward direction) of the rotor 60, and the left direction indicates the valve closing direction (downward direction). The origin of step 0 is the limit position where the stopper 90 is restricted in rotation and the rotor 60 cannot rotate downward any more. Step M is the valve opening point at which the rotor 60 rotates upward. The value of M may be a predetermined common value, or may be a peculiar value different for each motor operated valve 1 . When the eigenvalue is used, the value of M indicating the valve opening step is stored in the non-volatile memory of the circuit board 118 . In the range from the origin to the valve opening point, the valve body 34 is pressed against the valve seat 24 by the elastic reaction force of the spring 116, so the valve closed state is maintained. When the rotor 60 continues to rotate upward from the origin 0 and exceeds the valve opening point M, the valve body 34 separates from the valve seat 24 and the valve is opened. When the upward rotation of the rotor 60 continues even after the valve opening point is exceeded, the valve opening degree gradually increases, and the flow rate from the inlet port 26 to the outlet port 28 increases.

This embodiment mainly relates to a technique for detecting a unique origin by the motor-operated valve 1 that has been assembled including the motor-operated valve control device realized by the circuit board 118 at the manufacturing stage.

FIG. 9 is a graph showing transitions of steps and rotor angles in the origin detection operation.
When origin detection is started, the step corresponding to the origin is, of course, unknown, and there is no origin information yet. The positions (steps) shown here do not refer to steps based on the origin described in FIG. 8, but to provisional steps.

A starting point 500 indicates the position (step) at which the rotation operation for origin detection is started and the rotor angle at that position. The rotor angle at the starting point 500 can be measured by an angle sensor. The illustrated ideal behavior line 502 indicates the relationship between the position (step) and the ideal rotor angle when the rotor 60 ideally operates according to the operation of the stepping motor, starting from the starting point 500 . That is, it can be said that it shows the relationship between the step and the indicated angle α indicated by the excitation pattern corresponding to the step. A measurement point appears on the ideal behavior line 502 when the rotor angle as designed by the excitation pattern corresponding to the step is realized without applying a force that suppresses the movement of the rotor 60 .

In the figure, a tuning upper limit line 504 is shown above the ideal behavior line 502 and a tuning lower limit line 506 is shown below the ideal behavior line 502 . The range between the lower tuning limit line 506 and the upper tuning limit line 504 is a tuning range 505 . A tuning range 505 is a range in which the stepping motor is estimated to be tuned. That is, if the rotor angle (sensing angle) measured at a certain step is within the tuning range 505, it can be estimated that the stepping motor is in a tuning state at that step. The range other than the tuning range 505 is the step-out range. The out-of-step range is the range in which the out-of-step state of the stepping motor is detected. That is, if the rotor angle measured at a certain step is within the step-out range, it can be estimated that the stepping motor is out-of-step at that step.

Note that in the reversal region 507 , the upper tuning line 504 is below the lower tuning line 506 . Therefore, the range between the tuning upper limit line 504 and the tuning lower limit line 506 is the out-of-tune range, and the range below the tuning upper limit line 504 and above the tuning lower limit line 506 is the tuning range 505 .

The arrows shown in the figure indicate the direction of transition in the origin detection operation. Specifically, the rotor 60 is rotated so that the valve body 34 faces the position where the stopper 90 contacts the guide member 36 (more strictly, the projection of the guide member 36). In this example, the rotor 60 is rotated downward. The stepping motor rotates one step at a time. The operation of the motor operated valve 1 when advancing one step is called a unit operation.

The motor-operated valve control device records the rotor angle (sensing angle) measured for each unit operation. Recording of the rotor angle will be described in detail later.

Further, the motor-operated valve control device determines whether or not the rotor 60 is stopped due to the contact of the stopper 90 with the guide member 36 based on the measured rotor angle (sensing angle) for each unit operation. judge. Immediately after the stopper 90 actually comes into contact with the guide member 36, it is difficult to determine from the measured rotor angle (sensing angle) that the rotor has stopped. This is because even if the measured rotor angle (sensing angle) deviates from the ideal rotor angle (indicated angle), it cannot be determined whether the rotor is in a stopped state or merely a blur that can occur during rotation. Therefore, the motor-operated valve control device determines that the rotor 60 is stopped when the actual rotor angle (sensed angle) deviates from the ideal rotor angle (indicated angle) to some extent.

The motor-operated valve control device detects the stopped state of the rotor 60 by applying the out-of-step determination logic. A stop mechanism (an example of a "second mechanism for limiting the axial movement of the valve body") that limits the axial movement of the valve body 34 by the stopper 90 coming into contact with the guide member 36 is also said to be a mechanism that causes step-out. I can say Therefore, in a sense, it is natural that the stop of the rotor 60 by the stop mechanism can be detected by the same logic as the step-out determination. Therefore, it is clearly possible to detect the stopped state of the rotor 60 by a method for determining out-of-step other than the method exemplified here. Further, application of such a method for determining out-of-step is a matter that can be sufficiently assumed as a modified example of the present embodiment.

FIG. 10(A) is a graph showing transitions between steps and rotor angles in ideal behavior.
Here, it is assumed that there is no deviation of the rotor angle during rotation and no error in the magnetic sensor 119 .

When the step proceeds in the valve closing direction, measurement points 415, 414, . Rotor 60 rotates from measurement point 415 to measurement point 405 , and these measurement points overlap ideal behavior line 502 .

A measurement point 404 represents a step at which the stopper 90 comes into contact with the guide member 36 and the rotation of the rotor 60 stops. Further, the steps progress in the order of measurement point 404, measurement point 403, measurement point 402, and measurement point 401, but the rotor angle does not change during this time. From the measurement point 404 to the measurement point 401, the deviation from the ideal rotor angle on the ideal behavior line 502 is small and stays within the tuning range 505, so it is not yet judged to be in a stopped state.

When the measurement point 400 is reached, the tuning range 505 is exited. In other words, it is determined that the rotor 60 has already stopped because the measurement point 400 has moved into the step-out range. At this stage, the motor-operated valve control device stops the progress of the step. Through the processing up to this point, the rotor angles at measurement points 415 to 400 are recorded.

The electric valve control device uses the recorded rotor angle data to identify the measurement point 404 when the rotor 60 actually stops. A method for identifying the step when the rotor 60 stops will be described later.

FIG. 10(B) is a graph showing transitions between steps and rotor angles in realistic behavior.
Here, it is assumed that the rotor angle fluctuates during rotation and an error occurs in the magnetic sensor 119 .

In practice, the angle of the rotor during rotation may fluctuate due to foreign matter being caught, vibration applied to the motor-operated valve 1, or the influence of an external force. Therefore, the rotor angle (sensed angle) during rotation may deviate slightly from the ideal rotor angle (indicated angle), as shown from measurement point 314 to measurement point 305 .

In addition, since an error occurs in the measurement by the magnetic sensor 119, the rotor angle (sensing angle) in the stopped state is not constant as shown from the measurement point 304 to the measurement point 300. FIG.

FIG. 11A is a graph for explaining a method of determining the origin on the premise of ideal behavior.
FIG. 11(A) is an enlarged part of FIG. 10(A). In this example, the motor-operated valve control device identifies the measurement point 404 at which the rotor 60 actually stops, based on the measurement point 400 at which the rotor 60 is determined to be in a stopped state.

In order to specify the measurement point 404 at which the rotor 60 actually stopped, the electric valve control device determines the previous measurement point 405, that is, the measurement point 405 that was in the final rotation state. Specifically, by comparing the rotor angle (sensible angle) at measurement point 400 determined to be in a stopped state with the rotor angle (sensible angle) at measurement point 405, It can be determined that there was If the rotor angle (detection angle) difference is large, it means that the rotor 60 was rotating regardless of the error of the magnetic sensor 119 .

The maximum value of the deviation of the rotor angle (perceived angle) appearing as a measurement error of the magnetic sensor 119 is called an "error angle". The error angle is used as a threshold value (an example of a “predetermined value”) for determination based on the rotor angle (detection angle) difference when determining the step (measurement point 405) in the last rotating state.

The rotor angle (detection angle) at measurement point 400 at which rotor 60 is determined to be in the stopped state is represented by Y(0). An error range 515 is set with Y(0) as the median. The maximum angle Ymax of the error range 515 is the angle obtained by adding the error angle to Y(0). The minimum angle Ymin of the error range 515 is the angle obtained by subtracting the error angle from Y(0). An error range 515 indicates the error range of the magnetic sensor 119 with reference to the rotor angle (perceived angle) at the measurement point where the rotor 60 is determined to be in the stopped state. That is, the error range 515 is a reference range for determining whether or not the measured rotor angle (perceived angle) corresponds to the stopped state. The reference range is the range corresponding to the stop state, and the error range 515 is an example of the reference range.

FIG. 11B is a graph for explaining a method of determining the origin on the premise of realistic behavior.
The rotor angles (sensing angles) measured at measurement points 300 to 304 where the rotor 60 is stopped include measurement errors by the magnetic sensor 119 . Therefore, it actually swings slightly up and down in the figure. However, any of the measurement points 300 to 304 falls within the error range 515 . On the other hand, the measurement point 305 that was in the rotating state is outside the error range 515 . Focusing on this point, the motor-operated valve control device traces back the progress order of the steps from the record of the measurement point 300 and determines whether the rotor angle (sensing angle) at each measurement point is included in the error range 515. . Then, a measurement point 305 indicating a rotor angle (perceived angle) outside the error range 515 is found. The first measurement point 305 found in the retrograde order actually corresponds to the last rotating step. The measurement point 305 that is first determined to be outside the error range 515 corresponds to "the most recent step where the rotor angle (detection angle) difference is greater than a predetermined value (in this example, the error angle)".

After specifying the measurement point 305 at which the rotor angle (sensible angle) is determined to be outside the error range 515 first in the retrospective order, the electric valve control device moves from that measurement point 305 to the next measurement point in the order of progress of the steps. It is determined that 304 corresponds to the step at which the rotor 60 has actually stopped. Then, this step is determined as the origin to be stopped by the stop mechanism.

In principle, the origin can be detected in this way. However, when the rotor angle (perceived angle) is expressed as a parameter from 0 to 360 (deg) at the stage of implementation, there is a point to be noted as numerical processing. It is a problem of handling the boundary between 360 (deg) and 0 (deg).

An angle (deg) represented in the range of 0 to 360 is a kind of parameter that cycles with a predetermined width (360 in this example). If the error range 515 straddles the boundary between 360 (deg) and 0 (deg), it cannot be dealt with by a simple magnitude comparison alone.

FIG. 12A is a graph showing an example in which the error range 515 does not cross the boundary of angles.
Rotor angle (perceived angle) at measurement point 300a where rotor 60 is determined to be in a stopped state: the sum of Y(0) plus the error angle does not exceed 360 (deg), and the error angle from Y(0) is not a negative value, the relationship of maximum angle Ymax of error range 515>minimum angle Ymin of error range 515 is established.

In this case, if Y(n) represents the rotor angles (sensing angles) of the retrospective measurement points 301a to 305a, the events can be organized as follows. Note that n represents the number of going back, and indicates 1 to 5 in this example.
(Event 1) An event in which Y(n) is smaller than Ymin and larger than Ymax does not occur.
(Event 2) Y(n) is outside the error range 515 if Y(n) is less than Ymin and less than Ymax.
(Event 3) Y(n) is outside the error range 515 if Y(n) is greater than Ymin and greater than Ymax.
(Event 4) If Y(n) is greater than Ymin and less than Ymax, then Y(n) is within the error range 515;

FIG. 12B is a graph showing an example in which the upper side of the error range 515 straddles the angle boundary.
Rotor angle (detection angle) at measurement point 300b determined to be in the stopped state of rotor 60: If the sum of Y(0) and the error angle exceeds 360 (deg), 360 A value obtained by subtracting (deg), that is, a value slightly larger than 0, indicates the maximum angle Ymax of the error range 515 . In this case, the relationship of maximum angle Ymax of error range 515<minimum angle Ymin of error range 515 is established as illustrated.

In this case, the events can be organized as follows.
(Event 5) Y(n) is outside the error range 515 if Y(n) is less than Ymin and greater than Ymax.
(Event 6) If Y(n) is less than Ymin and less than Ymax, then Y(n) is within the error range 515;
(Event 7) If Y(n) is greater than Ymin and greater than Ymax, then Y(n) is within the error range 515;
(Event 8) An event in which Y(n) is greater than Ymin and less than Ymax does not occur.

FIG. 12C is a graph showing an example in which the lower side of the error range 515 crosses the boundary of angles.
If the difference value obtained by subtracting the error angle from Y(0), the rotor angle (sensing angle) at the measurement point 300c where the rotor 60 is judged to be stopped, is a negative value, 360 is added to the difference value. A value obtained in addition, that is, a value slightly smaller than 360 (deg), indicates the minimum angle Ymin of the error range 515 . In this case, the relationship of maximum angle Ymax of error range 515<minimum angle Ymin of error range 515 is established as illustrated. In this case as well, the above-mentioned (phenomenon 5) to (phenomenon 8) are established.

These events are sorted out, and origin discrimination processing is performed according to the following flow.

1st step: rotor angle (perceived angle) at measurement point 300 where rotor 60 is determined to be in a stopped state: based on Y(0) and the error angle, the maximum angle Ymax of error range 515 and the minimum angle of error range 515 Calculate Ymin.

Specifically, if the sum of the rotor angle (sensible angle) Y(0) at the measurement point 300 determined to be in the stopped state of the rotor 60 and the error angle does not exceed 360 (deg), the sum is the maximum angle Ymax of the error range 515 . On the other hand, when the sum of Y(0) plus the error angle exceeds 360 (deg), the value obtained by subtracting 360 (deg) from the sum is taken as the maximum angle Ymax of the error range 515. (See FIG. 12(B)).

If the difference obtained by subtracting the error angle from the rotor angle (sensing angle) Y(0) at the measurement point 300 determined to be in the stopped state of the rotor 60 is not a negative value, the difference is treated as an error. Let the minimum angle Ymin of the range 515 be. On the other hand, when the value of the difference obtained by subtracting the error angle from Y(0) is a negative value, the value obtained by adding 360 (deg) to the value of the difference is taken as the minimum angle Ymin of the error range 515 (Fig. 12(C)).

Second step: Determine the magnitude relationship between the maximum angle Ymax of the error range 515 and the minimum angle Ymin of the error range 515 . Specifically, the truth or falsehood of the following determination formula A is determined.
Judgment formula A: Judgment result A=Ymax>Ymin

Third step: Determine the size relationship between Y(n), which is the rotor angle (sensing angle) of the measurement points 301 to 305 that have been traced back, and the minimum angle Ymin of the error range 515 . Specifically, the truth or falsehood of the following determination formula B is determined.
Judgment formula B: Judgment result B=Ymin<Y(n)

Fourth step: Determine the size relationship between Y(n), which is the rotor angle (sensing angle) of the retrospective measurement points 301 to 305, and the maximum angle Ymax of the error range 515. FIG. Specifically, the truth or falsehood of the following determination formula C is determined.
Judgment formula C: Judgment result C=Y(n)<Ymax

Fifth step: Using the determination results of the second to fourth steps, determine the truth or falsehood of the following determination expression Z.
Judgment formula Z: Judgment result Z=Judgment result A xor Judgment result B xor Judgment result C

FIG. 13 is a truth table for judging the inside and outside of the error range.
Based on the determination results of determination formula A, determination formula B, and determination formula C, determination formula Z can be determined. Then, if the determination result Z of the determination formula Z is true (1), the rotor angle (sensing angle) Y(n) of the measurement points 301 to 305, for example, is within the error range 515, and the determination formula Z is false (0), it can be determined that Y(n) is outside the error range 515 .

FIG. 14 is a functional block diagram of the electric valve control device 200. As shown in FIG.
Each component of the electric valve control device 200 includes hardware (control circuit) including a control circuit (microcomputer) on the circuit board 118, storage devices such as memory and storage, and wired or wireless communication lines connecting them. It is implemented by software that is stored in a storage device and that supplies processing instructions to the calculator. Computer programs may consist of device drivers and application programs, as well as libraries that provide common functionality to these programs. Each block described below represents a functional block rather than a hardware configuration.

The motor operated valve control device 200 includes a data processing section 202 , a communication section 204 , a reference information storage section 206 , a recorded data storage section 230 and a rotor interface section 208 .
The communication unit 204 functions as an interface with an external device via the connection terminal 81 . Rotor interface section 208 functions as an interface for magnetic sensor 119 and coil unit 75 . The reference information storage unit 206 stores origin information (reference information). The reference information storage unit 206 is a storage area configured in a nonvolatile memory. The recorded data storage unit 230 can store the rotor angle (perceived angle), step and excitation pattern at each of the measurement points 301 to 315 as recorded data. The recording data storage unit 230 may be a storage area configured in a volatile memory, or may be a storage area configured in a non-volatile memory. The number of records of measurement points to be retained is arbitrary, but may be, for example, the number of nth power of 2 (e.g., 8, 16, or 32) including the record of the latest step, and the data of old steps are discarded. do. That is, the area for storing records of rotor angles (sensed angles) may be a ring buffer. The number of recordings may be determined according to the characteristics of the driving method of the stepping motor (half-step, 1/4-microstep, 1/8-microstep, etc.). The data processing unit 202 executes various processes based on the reference information and various data acquired from the communication unit 204 and the rotor interface unit 208 . The data processing section 202 also functions as an interface for the communication section 204 , rotor interface section 208 , reference information storage section 206 and recording data storage section 230 .

Communication unit 204 includes a receiving unit 210 that receives data and commands from an external device, and a transmitting unit 212 that transmits data to the external device.

Rotor interface portion 208 includes a rotation instructing portion 214 and a rotation detecting portion 216 . Rotation instruction unit 214 outputs a drive current to each of U-phase coil 73a, V-phase coil 73b, and W-phase coil 73c according to the excitation pattern. The rotation detector 216 reads the duty ratio (angle value) from the current pulse received from the magnetic sensor 119 .

Data processing unit 202 includes rotation control unit 218 , stop detection unit 220 and origin determination unit 222 . A rotation control unit 218 controls the rotation instruction unit 214 to rotate the rotor in origin detection. Stop detection unit 220 detects a stop state of rotor 60 . The origin discrimination section 222 discriminates the origin from among the steps corresponding to the measurement points based on the recorded data.

FIG. 15 is a flow chart showing the main processing steps.
Rotation instruction unit 214 rotates rotor 60 upward by several steps, for example, about N steps (hereinafter referred to as “confirmation rise”) under the control of rotation control unit 218 (S10). After that, the rotation instruction unit 214 causes the rotor 60 to rotate downward under the control of the rotation control unit 218 . Confirmation lift allows the stepper motor to be tuned by aligning the rotor position and the excitation position. Also, when the rotor 60 starts rotating, there is a possibility that foreign matter such as metal scraps is caught in the screw feed mechanism 109 between the guide member 36 and the rotor 60 . Due to the reverse rotation of the rotor 60 that accompanies the confirmation ascent, the foreign matter caught in the rotor 60 can be released. In addition, it is possible to apply appropriate vibrations to the screw feed mechanism 109 by performing the confirming lift, and to encourage foreign matter to fall off the screw feed mechanism 109 .

The rotation control unit 218 controls the rotation instruction unit 214 so as to rotate downward at a predetermined rotation speed. The rotation instruction unit 214 rotates the rotor 60 downward step by step at a predetermined interval under the control of the rotation control unit 218 (S12). That is, the rotation instructing part 214 advances one step at a time in the direction in which the axial movement of the valve body 34 is restricted by the stop mechanism (in this example, the downward direction in which the stopper 90 contacts the guide member 36). Indicate the indicated angle to the stepping motor.

The rotation detector 216 acquires the rotor angle (perceived angle) based on the duty ratio (angle value) read from the current pulse received from the magnetic sensor 119 for each step. (S14).

The rotation control unit 218 adds the rotor angle (perceived angle), the step and the excitation pattern to the recording data for each step, and causes the recording data storage unit 230 to hold the data (S16).

As described with reference to FIGS. 9 and 10A, stop detection unit 220 detects the difference between the actual rotor angle (sensing angle) and the ideal rotor angle (indicating angle) as a reference value (in the tuned state). If it exceeds the range of deviation of the rotor angle that can be estimated to exist, the stopped state of the rotor is detected (Y in S18). If the difference between the actual rotor angle (sensible angle) and the ideal rotor angle (indicated angle) is equal to or less than the reference value, the stopped state of the rotor 60 is not detected (N of S18).

If the stopped state of the rotor 60 is not detected (N of S18), the process returns to S12 and repeats the above-described processes. When the stopped state of the rotor 60 is detected (Y of S18), the origin determination unit 222 performs origin determination processing (S20). As described with reference to FIG. 11B, the origin determination unit 222 traces back one step at a time from the step at which the stop state was detected in the recorded data, and determines the detection angle and the trace at the step at which the stop state was detected. It is determined whether or not the difference from the sensing angle in the step obtained is greater than a predetermined value (error angle in this example). Then, the origin determination unit 222 identifies the most recent step whose difference is greater than a predetermined value, and determines the next step in the traveling direction from the identified most recent step as the origin of rotation of the rotor 60 . A value larger than the error angle may be used as the predetermined value, and the next next step (example of the step advanced a predetermined number of times) in the traveling direction from the most recent step may be determined as the origin of the rotation of the rotor 60. .

More specifically, the origin determination unit 222 determines whether each traced measurement point is within or outside the error range 515 according to the above-described first to fifth steps and the truth table (FIG. 13). determine whether For the measurement points 305 outside the error range 515, it was determined that the difference between the sensing angle at the step where the stop state was detected and the sensing angle at the previous step was greater than a predetermined value (error angle in this example). It will be.

That is, the origin determining unit 222 determines the maximum angle to be an angle obtained by rotating the sensing angle at the step where the stop state is detected in the positive direction by a predetermined value (in this example, the error angle). An error range 515 is set in which the minimum angle is the angle rotated in the negative direction by a predetermined value from the corner. Then, the origin determination unit 222 determines that the difference in the sensing angle is larger than a predetermined value when the sensing angle in the backward step is out of the error range 515 . Further, when using a parameter (“degree” (deg) in this example) that circulates in a predetermined width (360 in this example) as the angle of the rotor 60, the origin determination unit 222 determines whether the error range 515 is inside or outside. The logical operation described above is performed in the processing for According to this logical operation, when the error range 515 (an example of the reference range) includes the boundary of the parameter and the maximum angle is smaller than the minimum angle (FIGS. 12B and 12C )), the range from the minimum angle of the error range 515 to the upper limit of the predetermined width (360 (deg) in this example) and the lower limit of the predetermined width (0 (deg) in this example) to the error range 515 The range up to the maximum angle is determined as the error range 515 . This way of thinking can also be used when the duty ratio is used as a parameter representing the angle of the rotor 60 .

Then, the origin determination unit 222 stores the excitation pattern of the measurement point determined as the origin in the reference information storage unit 206 as origin information (reference information) (S22). The origin discrimination section 222 may add the rotor angle (sensing angle) and/or the duty ratio (angle value) corresponding to the excitation pattern to the origin information (reference information).

As shown in FIGS. 12(B) and 12(C), the error range 515 of the motor-operated valve 1 is designed so as to avoid crossing the boundary of the angle range (0 (deg) and 360 (deg)). It is also conceivable to adjust the orientation or position of the mechanical parts during the assembly process. However, the work of adjusting the orientation or position of the mechanical parts in the assembly process is troublesome. According to this embodiment, the calculation process in the motor operated valve 1 can handle the problem without adjusting the orientation or position of the mechanical parts, so the load of the assembly work can be reduced.

[Modification 1]
In this embodiment, the origin, that is, the stop position by the stop mechanism that limits the axial movement of the valve body 34 is determined. (hereinafter referred to as "out-of-step trigger position") may be discriminated. In that case, instead of the stop detection unit 220, the step-out of the rotor 60 due to the limitation of the axial movement (for example, the pinching of metal scraps, etc.) can be detected based on the measured rotor angle (sensing angle) for each step. A step-out detector (not shown) for detecting the state is provided in the motor-operated valve control device 200 . The details of the processing in the step-out detection unit are the same as the processing in the stop detection unit 220 described in this embodiment. Further, instead of the origin determining section 222, a trigger position determining section (not shown) is provided in the motor operated valve control device 200. FIG. In the recorded data, the trigger position determination unit traces back one step at a time from the step in which the out-of-step state was detected, and determines the difference between the sensing angle in the step in which the out-of-step state was detected and the sensing angle in the retroactive step to be a predetermined value ( In this example, it is determined whether or not it is greater than the error angle). Then, the trigger position determination unit identifies the nearest step whose difference is greater than a predetermined value, and determines the next step in the traveling direction from the identified nearest step as the step-out trigger position. That is, the measurement point (step) determined as the origin in the present embodiment is determined as the step-out trigger position in the first modification. In Modification 1, the cause of step-out is not necessarily the stop mechanism.

[Modification 2]
In this embodiment, the stop position of the stop mechanism that restricts the axial movement of the valve body 34 in the valve closing direction, that is, the position where the lower stopper 90 contacts the guide member 36 is set as the origin. However, the origin may be a stop position by a stop mechanism that restricts the axial movement of the valve body 34 in the valve opening direction. In that case, the rotation control section 218 controls the rotation instructing section 214 to rotate upward. The stop detection unit 220 detects a stop state when the rotor angle (sensing angle) becomes below the tuning lower limit line 506 . The origin determination unit 222 finds a measurement point where the rotor angle (detection angle) is outside the error range 515 in the backward step, and determines the next measurement point in the traveling direction (upward direction) as the origin.

[Modification 3]
The motor-operated valve control device shown in this embodiment traces back the progress order of the steps from the record of the measurement point 300 to find the measurement point 305 indicating the rotor angle (perceived angle) that does not fall within the error range 515 . However, as a modification, the motor-operated valve control device finds the measurement point 304 that indicates the rotor angle (sensing angle) that falls within the error range 515 according to the progress order of the steps from the record of the measurement points (for example, the measurement point 315) during rotation. You may do so. It is determined that the first measurement point 304 found in the order of progress of the steps corresponds to the step at which the rotor 60 actually stopped. Then, this step is determined as the origin to be stopped by the stop mechanism. That is, the origin determination unit 222 identifies the step to be determined in the order of progress of the steps in the recorded data, and the difference between the sensing angle at the step where the stop state is detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. , and the step to be determined that is first determined to have a difference equal to or less than a predetermined value may be determined as the origin of rotation of the rotor. Alternatively, the trigger position discriminating section in Modification 1 may similarly discriminate, as the out-of-step trigger position, the step to be determined for which the difference is first determined to be equal to or less than a predetermined value. The same applies to Modification 2 as well.

[Modification 4]
In this embodiment, it is determined whether or not the difference between the sensing angle at the step at which the stop state was detected and the sensing angle at the previous step is greater than a predetermined value by going back one step from the step at which the stop state was detected. I gave an example. However, as a modified example, the origin determination unit 222 may perform determination retroactively from an intermediate step, omitting the determination at steps near the step where the stop state was detected. For example, the origin determination unit 222 does not perform determination up to the second step (measurement point 302 in FIG. 11B) immediately before the step where the stop state is detected, and does not perform determination until the third step (measurement point 303 in the same way). The determination may be made step by step. In other words, the origin discrimination section 222 may repeat the steps backward toward the origin from the middle of the step (measurement point 300 in the same way) where the stop state is detected. In the case of Modified Example 1, the trigger position determining section may similarly repeat the steps backward toward the step-out trigger position from the middle of the step where the stop state is detected. The same applies to Modification 2 as well.

[Modification 5]
In this embodiment, the most recent step in which the difference between the sensing angle at the step where the stop state is detected and the sensing angle at the previous step is greater than a predetermined value, An example has been shown in which the step is determined as the origin of rotation of the rotor. However, the step identified by the origin determination unit 222 as having a difference in sensing angle greater than a predetermined value is not limited to the most recent one. For example, the origin determination unit 222 may detect two consecutive steps in which the difference in sensing angle is larger than a predetermined value, and determine the next step in the traveling direction from the second step as the origin. good. In other words, the origin determination unit 222 may identify a step where the difference in sensing angles is greater than a predetermined value, and determine a step that is a predetermined number of steps in the traveling direction from the identified step as the origin. In the case of Modification 1, the trigger position determination unit similarly identifies a step in which the difference in sensing angle is larger than a predetermined value, and determines a step advanced by a predetermined number in the direction of travel from the identified step as the step-out trigger position. may The same applies to Modification 2 as well.

[Modification 6]
In the present embodiment, the stop position (origin) by the stop mechanism that restricts the axial movement of the valve body 34 in the valve closing direction is used as the reference position for controlling the electric valve 1. However, the reference position is the origin. is not limited to For example, by offsetting the origin, a step shifted from the stop position (origin) by a predetermined number in the valve opening direction may be determined as the reference position.

[Modification 7]
In this embodiment, the information of the origin (reference point) detected at the manufacturing stage is recorded in the reference information storage unit 206, and the information is used at the operational stage such as after being mounted on the vehicle. As a method other than this embodiment, the origin (reference point) is not detected and recorded at the manufacturing stage, and each time the motor-operated valve 1 is started to be used at the operational stage (for example, each time power is supplied from the vehicle), the present The origin determination unit 222 may detect the origin (reference point) by a method similar to that of the embodiment.

[Other Modifications]
Although an example of a three-phase stepping motor has been shown, a stepping motor other than the three-phase type may be used. For example, a two-phase stepping motor may be used.

In the above-described embodiment, the configuration in which the magnetic sensor 119 faces the sensor magnet 106 in the axial direction is exemplified (see FIG. 1). In a modification, the magnetic sensor may be arranged laterally (outside in the radial direction) of the sensor magnet. That is, both may be opposed in the radial direction. The outer peripheral surface of the sensor magnet may be magnetized. The number of poles can be appropriately set, for example, two poles in the valve body.

In the above embodiment, the configuration in which the rotor magnet 104 and the sensor magnet 106 are separated in the axial direction is exemplified. In a modification, the rotor magnet and the sensor magnet may be integrated. In the magnet portion molding step, the rotor magnet portion and the sensor magnet portion may be integrally molded. In that case, the area (outer diameter) of the sensor magnet may be increased so that the magnetic sensor can reliably detect the magnetic flux. Since the sensor magnet protrudes outside the rotor core, injection molding of the sensor magnet and the rotor magnet is facilitated.

In each embodiment, a laminated core (laminated magnetic core) is exemplified as the core of the stator. Alternatively, a dust core or other core may be employed. A dust core is also called a "dust core" and is obtained by pulverizing a soft magnetic material and coating it with a non-conductive resin or the like, kneading the powder with a resin binder, compression molding, and heating.

In each embodiment, the configuration in which the drive circuit, the control circuit, the communication circuit, and the power supply circuit are mounted on the lower surface of the circuit board is exemplified, but the circuits to be mounted can be changed as appropriate. For example, the drive circuit and power supply circuit may be implemented, while the control circuit may be located external to the motor operated valve. Also, each circuit may be mounted on the upper surface of the circuit board. Part or all of the motor-operated valve control device 200 may be installed outside the motor-operated valve.

In each embodiment, a PM stepping motor is used as the motor unit, but a hybrid stepping motor may be used. Also, in the above embodiment, the motor unit is a three-phase motor, but other motors such as two-phase, four-phase, and five-phase motors may be used. The number of electromagnetic coils in the stator is not limited to three or six, and may be appropriately set according to the number of phases of the motor.

The motor-operated valve of each embodiment is suitably applied to a refrigeration cycle that uses a CFC substitute (HFC-134a) as a refrigerant, but it can also be applied to a refrigeration cycle that uses a refrigerant with a high operating pressure, such as carbon dioxide. is. In that case, an external heat exchanger such as a gas cooler is arranged in the refrigeration cycle instead of the condenser.

In each embodiment, the electric valve is configured as an expansion valve, but it may be configured as an on-off valve or a flow control valve that does not have an expansion function.

In each embodiment, an example in which the electric valve is applied to the refrigerating cycle of an automotive air conditioner is shown, but the electric valve is applicable not only to vehicles but also to air conditioners equipped with an electric expansion valve. Also, it can be configured as an electrically operated valve that controls the flow of fluid other than refrigerant.

1 in this embodiment is applicable not only to electric vehicles but also to various vehicles.

The sensor magnet 106 may be magnetized on both sides with four poles (double-sided magnetization with two poles on the single-sided valve main body). Magnetic flux can be strengthened by reversing the polarity of the magnetic poles on the top and bottom surfaces. In this case, even if the rotor 60 is displaced in the valve closing direction and the distance between the sensor magnet 106 and the magnetic sensor 119 increases, the sensitivity of the magnetic sensor 119 can be maintained satisfactorily.

It should be noted that the present invention is not limited to the above-described embodiments and modifications, and can be embodied by modifying constituent elements without departing from the scope of the invention. Various inventions may be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments and modifications. Also, some components may be deleted from all the components shown in the above embodiments and modifications.

Reference Signs List 1 electric valve, 2 valve body, 3 motor unit, 5 body, 6 first body, 8 second body, 10 male thread, 12 seal housing portion, 14 seal ring, 16 concave fitting portion, 18 seal housing portion, 20 seal ring, 22 valve hole, 24 valve seat, 26 inlet port, 28 outlet port, 30 valve chamber, 32 operating rod, 34 valve body, 36 guide member, 38 male screw, 40 large diameter portion, 42 spring bearing, 44 spring bearing, 46 spring, 52 locking portion, 60 rotor, 62 rotating shaft, 64 stator, 66 can, 70 laminated core, 73 coil, 73a U-phase coil, 73b V-phase coil, 73c W-phase coil, 74 bobbin, 75 coil unit, 76 case, 77 cover, 78 stator unit, 79 connector, 80 seal housing, 81 connection terminal, 82 seal ring, 90 stopper, 102 rotor core, 104 rotor magnet, 106 sensor magnet, 108 female screw, 109 screw feed mechanism, 110 reduced diameter portion 112 bottom portion 114 stopper 116 spring 117 terminal 118 circuit board 119 magnetic sensor 120 slot 122 salient pole 124 slit 140 annular groove 144 annular groove 200 electric valve control device 202 Data processing unit 204 communication unit 206 reference information storage unit 208 rotor interface unit 210 reception unit 212 transmission unit 214 rotation instruction unit 216 rotation detection unit 218 rotation control unit 220 stop detection unit 222 origin determination section, 230 recording data storage section

Claims (9)

a stepping motor for rotating a rotor; a first mechanism for changing the rotational motion of the rotor to axial motion of the valve body; a second mechanism for limiting the axial motion of the valve body; A motor-operated valve control device for controlling a motor-operated valve having a sensor for obtaining a sensing angle,
a rotation instructing unit that instructs the stepping motor to indicate an indicated angle so as to advance step by step in a direction in which the axial motion is restricted by the second mechanism;
a rotation detector that acquires the sensed angle of the rotor from the sensor for each step;
a storage unit that holds the acquired sensing angle as recording data for each step;
a stop detection unit that detects a stop state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, the step is repeated from the step where the stop state was detected, and the difference between the sensing angle at the step where the stop state was detected and the sensing angle at the step that went back is a predetermined value. an origin determination unit that determines whether or not the difference is greater than the predetermined value, identifies a step in which the difference is greater than the predetermined value, and determines a step advanced by a predetermined number in the traveling direction from the identified step as the origin of rotation of the rotor; A motor-operated valve control device comprising: Using a parameter that circulates with a predetermined width as the angle of the rotor,
The origin discriminating unit determines an angle obtained by rotating the sensing angle in the step at which the stop state is detected in a positive direction by the predetermined value as a maximum angle, and sets the angle from the sensing angle at the step at which the stop state is detected to the setting a reference range whose minimum angle is an angle rotated in a negative direction by a predetermined value, and determining that the difference is greater than the predetermined value when the sensing angle in the retroactive step deviates from the reference range;
When the reference range includes the boundary of the parameter and the maximum angle indicates a value smaller than the minimum angle, the range from the minimum angle of the reference range to the upper limit of the predetermined width and from the lower limit of the predetermined width to the 2. The motor-operated valve control device according to claim 1, wherein a logical operation is performed to determine the range up to the maximum angle of the reference range as the reference range. A motor-operated valve control for controlling a motor-operated valve having a stepping motor for rotating a rotor, a mechanism for changing the rotational motion of the rotor to axial motion of the valve body, and a sensor for measuring the angle of the rotor to obtain a sensed angle. a device,
a rotation instruction unit that instructs the stepping motor to indicate an instruction angle so as to advance one step at a time;
a rotation detector that acquires the sensed angle of the rotor from the sensor for each step;
a storage unit that holds the acquired sensing angle as recording data for each step;
an out-of-step detection unit that detects an out-of-step state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, the step is repeated from the step where the out-of-step state was detected, and the difference between the sensing angle at the step where the out-of-step state was detected and the sensing angle at the backward step is Trigger position determination for determining whether or not the difference is greater than a predetermined value, identifying a step in which the difference is greater than the predetermined value, and determining a step advanced by a predetermined number in the advancing direction from the identified step as a step-out trigger position. A motor-operated valve control device comprising: a stepping motor for rotating a rotor; a first mechanism for changing the rotational motion of the rotor to axial motion of the valve body; a second mechanism for limiting the axial motion of the valve body; a sensor for obtaining a sensing angle; and a computer for controlling an electrically operated valve having:
a function of instructing the stepping motor to indicate a pointing angle so as to advance step by step in a direction in which the axial motion is restricted by the second mechanism;
a function of acquiring the sensed angle of the rotor from the sensor for each step;
A function of holding the acquired sensing angle as recorded data for each step;
a function of detecting a stopped state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, the step is repeated from the step where the stop state was detected, and the difference between the sensing angle at the step where the stop state was detected and the sensing angle at the step that went back is a predetermined value. a function of determining whether the difference is greater than the predetermined value, identifying a step in which the difference is greater than the predetermined value, and determining, as an origin of rotation of the rotor, a step advanced by a predetermined number in the traveling direction from the identified step; A motor-operated valve control program characterized by exerting. A computer for controlling a motor-operated valve having a stepping motor for rotating a rotor, a mechanism for changing the rotational motion of the rotor to axial motion of the valve body, and a sensor for measuring the angle of the rotor to obtain a sensed angle,
a function of instructing the stepping motor to indicate an indicated angle so as to advance one step at a time;
a function of acquiring the sensed angle of the rotor from the sensor for each step;
A function of holding the acquired sensing angle as recorded data for each step;
a function of detecting a step-out state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, the step is repeated from the step where the out-of-step state was detected, and the difference between the sensing angle at the step where the out-of-step state was detected and the sensing angle at the backward step is a function of determining whether or not the difference is greater than a predetermined value, identifying a step in which the difference is greater than the predetermined value, and determining a step advanced by a predetermined number in the traveling direction from the identified step as a step-out triggering position; A motor-operated valve control program characterized by exhibiting a stepping motor for rotating a rotor; a first mechanism for changing the rotational motion of the rotor to axial motion of the valve body; a second mechanism for limiting the axial motion of the valve body; A motor-operated valve control device for controlling a motor-operated valve having a sensor for obtaining a sensing angle,
a rotation instructing unit that instructs the stepping motor to indicate an indicated angle so as to advance step by step in a direction in which the axial motion is restricted by the second mechanism;
a rotation detector that acquires the sensed angle of the rotor from the sensor for each step;
a storage unit that holds the acquired sensing angle as recording data for each step;
a stop detection unit that detects a stop state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, a step to be determined is specified according to the order of progress of the steps, and a difference between the sensing angle at the step where the stop state is detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. and an origin determination unit configured to determine whether or not the difference is equal to or less than the predetermined value as the origin of rotation of the rotor. Electric valve controller. A motor-operated valve control for controlling a motor-operated valve having a stepping motor for rotating a rotor, a mechanism for changing the rotational motion of the rotor to axial motion of the valve body, and a sensor for measuring the angle of the rotor to obtain a sensed angle. a device,
a rotation instruction unit that instructs the stepping motor to indicate an instruction angle so as to advance one step at a time;
a rotation detector that acquires the sensed angle of the rotor from the sensor for each step;
a storage unit that holds the acquired sensing angle as recording data for each step;
an out-of-step detection unit that detects an out-of-step state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, a step to be determined is specified according to the order of progress of the steps, and a difference between the sensing angle at the step in which the step-out state is detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. and a step-out trigger position determination unit that determines whether or not the difference is equal to or smaller than the predetermined value, and determines the step to be determined first as the step-out trigger position. electric valve controller. a stepping motor for rotating a rotor; a first mechanism for changing the rotational motion of the rotor to axial motion of the valve body; a second mechanism for limiting the axial motion of the valve body; a sensor for obtaining a sensing angle; and a computer for controlling an electrically operated valve having:
a function of instructing the stepping motor to indicate a pointing angle so as to advance step by step in a direction in which the axial motion is restricted by the second mechanism;
a function of acquiring the sensed angle of the rotor from the sensor for each step;
A function of holding the acquired sensing angle as recorded data for each step;
a function of detecting a stopped state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, a step to be determined is specified according to the order of progress of the steps, and a difference between the sensing angle at the step where the stop state is detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. and a function of determining whether or not the difference is equal to or less than the predetermined value as the origin of rotation of the rotor. valve control program. A computer for controlling a motor-operated valve having a stepping motor for rotating a rotor, a mechanism for changing the rotational motion of the rotor to axial motion of the valve body, and a sensor for measuring the angle of the rotor to obtain a sensed angle,
a function of instructing the stepping motor to indicate an indicated angle so as to advance one step at a time;
a function of acquiring the sensed angle of the rotor from the sensor for each step;
A function of holding the acquired sensing angle as recorded data for each step;
a function of detecting a step-out state of the rotor due to the limitation of the axial motion based on the acquired sensing angle for each step;
In the recorded data, a step to be determined is specified according to the order of progress of the steps, and a difference between the sensing angle at the step in which the step-out state is detected and the sensing angle at the step to be determined is equal to or less than a predetermined value. and determining whether or not the difference is equal to or less than the predetermined value, and determining the step to be determined for which the difference is equal to or less than the predetermined value as a step-out trigger position. valve control program.

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