JP2023000262A - Electric valve control device, adjustment device, electric valve control program, and adjustment program - Google Patents

Abstract

To control a stepping motor so as to reduce a rotation error of a rotor of an electric valve.SOLUTION: An electric valve control device comprises: an excitation pattern correction value storage part connected to an electric valve having a stepping motor for rotating a rotor by a drive current which is applied in an excitation pattern corresponding to a step and a mechanism for changing a rotation motion of the rotor to an axial line motion of a valve body, and storing an excitation pattern correction value which is set for each individual electric valve; a rotation control part for correcting the excitation pattern corresponding to the step on the basis of the excitation pattern correction value; and a rotation indication part for applying the drive current to the stepping motor in the corrected excitation pattern.SELECTED DRAWING: Figure 24

Description

TECHNICAL FIELD The present invention relates to an electrically operated valve, and more particularly to a method for controlling a stepping motor.

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, electric valves equipped with stepping motors as drive units 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 also called an "origin", the rotation of the rotor is restricted by a stopper (see Patent Document 2, for example).

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

When a load is applied to the stepping motor, step-out may occur. Loss of synchronism is a phenomenon in which rotation induction in a stepping motor is lost due to a sudden change in speed, overload, or the like. Even if there is no step-out, when a load is applied to the stepping motor, the rotation will be delayed to some extent. This delay produces an error in the rotation angle and affects the valve opening control of the motor operated valve.

The error in the rotation angle depends on the driving characteristics of the stepping motor and the characteristics of the load applied to the rotor. Based on these characteristics, it is desirable to control the stepping motor so as to obtain a more accurate rotation angle and improve the accuracy of the valve opening.

SUMMARY OF THE INVENTION It is a primary object of the present invention to provide a technique for controlling a stepping motor so as to reduce rotational error of the rotor of a motor-operated valve.

A motor-operated valve control device according to one aspect of the present invention includes a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, and a mechanism that changes the rotary motion of the rotor into axial motion of the valve body. An excitation pattern correction value storage unit that is connected to the motor-operated valve and stores an excitation pattern correction value that is set for each individual motor-operated valve, and a rotation control unit that corrects the excitation pattern corresponding to the step based on the excitation pattern correction value. and a rotation instruction unit that applies a drive current to the stepping motor according to the corrected excitation pattern.

An adjustment device according to an aspect of the present invention includes a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that changes the rotary motion of the rotor into axial motion of the valve body, and an angle of the rotor. and an elastic body that applies an elastic force in the axial direction of the valve body. Acquisition of sample data from the motor-operated valve control device including a step in the operation of rotating the rotor in one of the first rotation directions in which the is larger and a parameter indicating the angle of the rotor detected by the sensor in the step a correction value calculation unit that calculates an excitation pattern correction value that advances the excitation pattern in the operation in the first rotation direction based on the sample data; and a correction that sets the calculated excitation pattern correction value in the motor-operated valve control device. and a value setting unit.

A motor-operated valve control device according to one aspect of the present invention includes a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that changes the rotary motion of the rotor into axial motion of a valve body, a rotor and an elastic body that applies elastic force in the axial direction of the valve body. a sample generator for generating sample data including a step in the operation of rotating the rotor in the first rotation direction and a parameter indicating the angle of the rotor detected by the sensor in the step; A correction value calculation unit for calculating an excitation pattern correction value for leading the excitation pattern in direction operation, and a correction value storage unit for storing the calculated excitation pattern correction value.

A motor-operated valve control program according to one aspect of the present invention has a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, and a mechanism that changes the rotary motion of the rotor into axial motion of the valve body. A computer connected to the motor-operated valve has a function to correct the excitation pattern corresponding to the step based on the excitation pattern correction value set for each individual motor-operated valve, and a drive current to the stepping motor according to the corrected excitation pattern. and the function of applying the voltage.

An adjustment program according to an aspect of the present invention includes a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that changes the rotary motion of the rotor into axial motion of the valve body, and an angle of the rotor. and an elastic body that applies an elastic force in the axial direction of the valve body to a computer that can be connected to a motor-operated valve control device connected to the motor-operated valve. Acquire sample data from the motor-operated valve control device, including the step in the operation of rotating the rotor in one of the first rotation directions in which the load torque becomes larger, and the parameter indicating the angle of the rotor detected by the sensor in the step a function of calculating an excitation pattern correction value that advances the excitation pattern in the operation in the first rotation direction based on the sample data; a function of setting the calculated excitation pattern correction value in the motor-operated valve control device; demonstrate.

An electric valve control program according to one aspect of the present invention includes a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that changes the rotary motion of the rotor into axial motion of the valve body, and a rotor. and an elastic body that applies elastic force in the axial direction of the valve body. A function of generating sample data including a step in the operation of rotating the rotor in one of the first rotation directions and a parameter indicating the angle of the rotor detected by the sensor in the step; A function of calculating an excitation pattern correction value for leading an excitation pattern in operation in the rotation direction and a function of storing the calculated excitation pattern correction value are exhibited.

According to the present invention, the stepping motor can be controlled so as to reduce the rotation error of the rotor of the motor-operated valve.

1 is a cross-sectional view showing an electrically operated valve according to an embodiment; FIG. FIG. 3 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; FIG. 9A is a diagram showing an overview of torque balance during valve stoppage. FIG. 9B is a diagram showing an overview of the torque balance at the start of upward rotation. FIG. 9C is a diagram showing an overview of the torque balance at the start of downward rotation. 4 is a graph showing changes in driving torque; FIG. 11A is a graph showing an uncorrected excitation pattern and an ideal duty ratio. FIG. 11B is a graph showing an uncorrected excitation pattern and an ideal duty ratio. FIG. 12A is a graph showing an uncorrected excitation pattern and an uncorrected duty ratio during upward rotation. FIG. 12B is a graph showing an uncorrected excitation pattern and an uncorrected duty ratio during upward rotation. FIG. 13A is a graph showing the excitation pattern with correction and the duty ratio with correction during upward rotation. FIG. 13B is a graph showing the excitation pattern with correction and the duty ratio with correction during upward rotation. 7 is a graph for explaining how to obtain an excitation pattern correction value; FIG. 10 is a diagram showing an example of parameters during upward rotation without correction; FIG. 10 is a diagram showing an example of parameters during downward rotation without correction; 7 is a graph for explaining results of excitation pattern correction; FIG. 10 is a diagram showing an example of parameters during upward rotation with correction; FIG. 10 is a diagram showing an example of parameters during downward rotation with correction; FIG. 3 is a functional block diagram of an adjusting device and an electric valve control device; FIG. 10 is a sequence diagram showing an adjustment process; 4 is a flow chart showing the processing steps of the electric valve control device; 4 is a flow chart showing an excitation pattern correction value calculation process; 4 is a flow chart showing the processing steps of the electric valve control device; FIG. 11 is a functional block diagram of an electric valve control device in Modification 3; 10 is a flowchart showing a correction value setting process of the motor-operated valve control device in Modification 3. FIG.

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 chamber 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 body 34 and its drive mechanism are arranged and that encloses 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 restricted 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 with a coil 73 (electromagnetic coil) 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 mold 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 rotary shaft 62 is a cylindrical shaft with a bottom, 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 body 34 is moved (lifted/lowered) in the axial direction, that is, in the opening/closing direction of the valve portion.

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 a control signal to the drive circuit, a communication circuit for the control circuit to communicate with an external device or adjustment device, each circuit and the motor ( A power supply circuit and the like for supplying power to the coil) 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 projection (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 at equal intervals around the axis L of the rotor 60 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 body 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 degrees×4 rotations÷u1 degrees=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. 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 opening direction (upward direction) of the rotor 60, and the left direction indicates the 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 valve element 34 starts to rise. 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.

A load torque is generated by the frictional resistance force and rotational force in the screw feed mechanism 109 in both the valve closed state from the origin to the valve open point and the valve open state from the valve open point to the highest point. The torque generated in the rotor 60 will be described below.

FIG. 9A is a diagram showing an overview of torque balance during valve stoppage.
The clockwise rotation is the upward rotation direction of the rotor 60 and the counterclockwise rotation is the downward rotation direction of the rotor 60 . As described with reference to FIG. 1, a spring 46 is interposed between the spring bearings 42 and 44 to bias the valve body 34 in the valve closing direction. A spring 46 applies a load to the screw feed mechanism 109 . The mechanism holds the position of the rotor 60 by the frictional force of the screw portion so that the rotor 60 does not rotate freely due to vibration or the like under the non-excitation condition due to this load.

In the threaded portion, when an axial load is applied, a frictional force is generated and a rotational force is also generated. That is, of the axial force generated on the threaded surface by the elastic force of the spring 46, the component force parallel to the threaded surface generates a slight torque in the valve closing direction of the rotor 60 as a rotational force. Rotational torque due to the rotational force has a constant magnitude in the downward rotation direction. While the valve is stopped, no drive torque is generated by the motor unit 3, so friction torque having the same magnitude as the rotational torque is generated in the opposite direction to the rotational torque. The friction torque at this time is not the maximum. When the rotational torque increases or decreases due to vibration or the like, the frictional torque changes to maintain torque balance. This prevents rotation and maintains the stopped state.

FIG. 9B is a diagram showing an overview of the torque balance at the start of upward rotation.
It shows the state just before the drive torque generated in the direction of upward rotation increases and it starts to move. Frictional torque is developed in the direction of downward rotation to balance the driving and rotating torques. The friction torque at this time is maximum. The torque that is the sum of the friction torque and the rotation torque is the load torque of the rotor 60 . When the drive torque exceeds the magnitude of this load torque, the rotor 60 begins to rotate upward.

FIG. 9C is a diagram showing an overview of the torque balance at the start of downward rotation.
It shows the state just before the driving torque generated in the direction of downward rotation increases and it starts to move. Frictional torque is generated in the direction of upward rotation to oppose the rotational torque and drive torque that are generated in the direction of downward rotation. The friction torque at this time is maximum. The torque that is the sum of the friction torque and the rotation torque is the load torque of the rotor 60 . When the drive torque exceeds the magnitude of this load torque, the rotor 60 begins to rotate upward.

As shown in FIGS. 9B and 9C, in the case of upward rotation, the rotor 60 does not start to move unless a larger driving torque is applied than in the case of downward rotation.

FIG. 10 is a graph showing changes in drive torque.
The driving torque of the motor unit 3 is determined by the electrical angle indicated by the excitation pattern (hereinafter referred to as the “ideal electrical angle”) and the electrical angle corresponding to the actual attitude of the rotor 60 (hereinafter referred to as the “actual electrical angle”). ). This electrical angle difference is defined as the ideal electrical angle minus the actual electrical angle. The drive torque can be calculated as a sine value with the electrical angle difference as a variable. Therefore, a sine curve is drawn as shown. In this figure, the drive torque is shown with a ratio of 1 to the maximum drive torque.

The electrical angle difference is proportional to the difference between the step corresponding to the excitation pattern (hereinafter referred to as the "ideal step") and the step corresponding to the actual attitude of the rotor 60 (hereinafter referred to as the "actual step"). in a relationship. This step difference is defined as ideal step minus actual step. Therefore, the magnitude relationship between the electrical angle difference in a certain state A and the electrical angle difference in another state B matches the magnitude relationship between the step difference in the state A and the step difference in the state B. FIG.

A description will be given of how the drive torque changes as the electrical angle difference increases. When the electrical angle difference is 0, no driving torque is generated. As the electrical angle difference increases, the driving torque increases. The driving torque becomes maximum when the electrical angle difference is 90 degrees. As the electrical angle difference further increases, the driving torque begins to decrease. If the drive torque falls below the load torque while the drive torque is decreasing, it is considered that a step-out phenomenon actually occurs.

Therefore, if the step n is changed to rotate upward, the rotor 60 will not rotate until the drive torque exceeds the load torque. When the drive torque exceeds the load torque, rotor 60 begins to rotate. After that, the actual rotor angle follows the ideal rotor angle while the electrical angle difference remains. As long as the electrical angle difference does not increase and the driving torque does not fall below the load torque as described above, follow-up continues.

In this example, a thick line 400 indicates the drive torque shown in FIG. 9(B). That is, at point 402 where the step difference is 5, the drive torque and the load torque of the upward rotation are balanced. Then, at point 404 in upward rotation, the rotor 60 begins to move.

In this example, a thick line 410 indicates the drive torque shown in FIG. 9(C). That is, at point 412 where the step difference is -1, the drive torque and the load torque for downward rotation are balanced. Then, at point 414 in downward rotation, the rotor 60 begins to move.

The magnitude of the drive torque described here varies from one motor-operated valve 1 to another. Therefore, the magnitude of the electrical angle to produce a certain level of drive torque may vary from individual to individual. The relationship between the electrical angle and the drive torque is not necessarily uniform for all the motor-operated valves 1 . For example, the reason for this is that the magnitude of the magnetic force generated by the coil 73 of the stator 64 varies.

FIGS. 11A and 11B are graphs showing an uncorrected excitation pattern and an ideal duty ratio. These figures show ideal behavior assuming no load torque. Correction of the excitation pattern will be described later, but the excitation pattern is not corrected here.

11A shows the range of steps 100-148, and FIG. 11B shows the range of steps 100-112. These ranges correspond to the valve open state. A non-correction excitation pattern is determined corresponding to step n. In this example, the excitation pattern ID decreases by one as the step number n increases by one. An uncorrected excitation pattern is represented as Rp(n). Also, the excitation pattern is identified using the excitation pattern ID number.

The ideal duty ratio, assuming no load torque, increases at a constant rate as the step increases. In this example, the amount of change in duty ratio per step is represented by j. An ideal duty ratio is represented as D(n). The ideal duty ratio is a value assumed to be output from the magnetic sensor 119 .

If there is no load torque, step n and duty ratio D(n) theoretically show the same correspondence regardless of the direction of rotation. Next, the behavior when the load torque is considered will be described.

12(A) and 12(B) are graphs showing the uncorrected excitation pattern and the uncorrected duty ratio during upward rotation. In practice, a load torque is produced. Here, attention is focused on the behavior during upward rotation shown in FIG. 9(B). The behavior during downward rotation will be described later with reference to FIG. The range of steps is the same as in FIG.

As explained in connection with FIG. 10, the rotor 60 does not rotate until the step difference increases to five. Therefore, if the duty ratio of step 100 is denoted by i, i of the duty ratio does not change even when proceeding from step 100 to step 105 . The excitation pattern is not corrected here. The duty ratio when the excitation pattern is not corrected is referred to as "uncorrected duty ratio". The uncorrected duty ratio during upward rotation is represented by Du(n). The uncorrected duty ratio Du(n) is a value actually output from the magnetic sensor 119 .

From step 106, the rotor 60 starts rotating upward at a constant pace, and the uncorrected duty ratio Du(n) increases. For example, the duty ratio Du(109) output from the magnetic sensor 119 in step 109 is i+4j, which is smaller than the ideal duty ratio D(109) i+9j by 5j. In this way, the value obtained by subtracting the uncorrected duty ratio Du(n) during upward rotation from the ideal duty ratio D(n) is called the "uncorrected duty ratio difference during upward rotation", and is expressed as ΔDu(n). show. It can be said that the rotation of the rotor 60 is delayed by an electrical angle corresponding to this duty ratio difference of 5j.

The rotation delay of the rotor 60 can also be grasped as a step difference. For example, the non-corrected duty ratio Du(109)=i+4j at step 109 is at the same level as the ideal duty ratio D(104), so it is considered that step 104 remains substantially. A step corresponding to an ideal duty ratio equal to the actual duty ratio is called a "substantial step". The actual step during upward rotation without correction is referred to as "substantial step without correction during upward rotation" and represented by Su(n). The difference obtained by subtracting the actual step Su(n) from the indicated step n during upward rotation is referred to as the "uncorrected step difference during upward rotation" and is represented by ΔSu(n). If the amount of change in duty ratio per step is represented by a constant U, ΔSu(n) is calculated by Equation 1 below. In this example the constant U is equal to j.
ΔSu(n)=ΔDu(n)/U [Formula 1]

As shown, the uncorrected step difference ΔSu (109) during upward rotation at step 109 is 5, which means that the response of the motor unit 3 is shifted by 5 steps at step 109. FIG. Therefore, the rotation of the rotor 60 is delayed.

If an error occurs in the amount of displacement of the rotor 60 due to the delay in the mechanical response, the axial position of the valve body 34 is shifted, and the accuracy of the valve opening is lowered. As a result, for example, when the motor-operated valve 1 is used as an expansion valve of a refrigeration cycle, there arises a problem that it becomes difficult to accurately adjust the flow rate of the refrigerant. The delay in the rotation of the rotor 60 also affects the step-out detection process for detecting step-out based on the difference between the angle instructed to the motor unit 3 and the angle detected by the magnetic sensor 119 . As described above, if the rotation of the rotor 60 is delayed during the upward rotation, the angle difference monitored by the step-out detection process will increase accordingly, and the step-out will be likely to be determined.

Based on these problems, in the present embodiment, the motor unit 3 is operated by correcting the excitation pattern corresponding to the steps in order to suppress the delay in rotation of the rotor 60 . Then, the error caused in the displacement amount of the rotor 60 is reduced.

13(A) and 13(B) are graphs showing the excitation pattern with correction and the duty ratio with correction during upward rotation. These show the behavior when the excitation pattern is corrected. The range of steps is the same as in FIGS. 11 and 12. FIG.

In this example, correction is made by subtracting two from each excitation pattern as indicated by the black arrows. That is, the excitation pattern correction value is -2. An excitation pattern correction value is represented as ΔRp. Further, the corrected excitation pattern is called "excitation pattern with correction" and is represented by Rp'(n). A formula for calculating the corrected excitation pattern Rp'(n) is expressed by Formula 2.
Rp'(n)=Rp(n)+ΔRp [Formula 2]

In step 103 with correction, the excitation pattern is the same as in step 105 without correction, so the starting torque and load torque are balanced as in step 105 in FIG. Then, in step 104 after the correction, the rotor 60 starts rotating as in step 106 of FIG. Thereafter, the rotor 60 starts rotating upward at a constant pace. The duty ratio represented by the excitation pattern with correction is referred to as the "duty ratio with correction", and the "duty ratio with correction" during upward rotation is represented by Du'(n).

As indicated by the white arrow, the correction increases the duty ratio and approaches the ideal duty ratio D(n). A value obtained by subtracting the corrected duty ratio Du'(n) during upward rotation from the ideal duty ratio D(n) is referred to as the "corrected duty ratio difference during upward rotation" and is represented by ΔDu'(n). That is, ΔDu'(n) is calculated by Equation 3 below.
ΔDu′(n)=D(n)−Du′(n) [Formula 3]

For example, the corrected duty ratio difference ΔDu' (109) during upward rotation in step 109 is 3j. It is reduced compared to the uncorrected duty ratio difference ΔDu(109)=5j shown in FIG. 12(B). In other words, it means that the angle of the rotor 60 has approached the ideal by correcting the excitation pattern.

Also, the step difference is reduced. After the excitation pattern is corrected, the difference obtained by subtracting the actual step from the indicated step during upward rotation is referred to as the "corrected step difference during upward rotation" and is represented by ΔSu'(n). For example, the corrected step difference ΔSu' (109) at step 109 during upward rotation is 3, which is two smaller than the uncorrected step difference ΔSu (109) during upward rotation shown in FIG. It's becoming This is due to the preceding two excitation patterns. In this way, if the excitation pattern is preceded to compensate for the poor response of the motor unit 3, the rotation of the rotor 60 is started earlier, and the above-described delay in rotation is suppressed. ΔSu′(n) is represented by Equation 4 below.
ΔSu′(n)=ΔDu′(n)/U [Formula 4]

FIG. 14 is a graph for explaining how to obtain the excitation pattern correction value.
Similar to FIG. 12, it shows the behavior of upward rotation and downward rotation without correction. By collecting parameter values related to this behavior, sample data used for the excitation pattern correction value calculation process is obtained. In this example, it is assumed that data on samples for one cycle of the electrical angle is obtained. In the sample data, the step n and the duty ratio output from the magnetic sensor 119 are associated with each sample.

The behavior of downward rotation, which was not explained in FIG. 12, will be explained. The uncorrected duty ratio during downward rotation is denoted by Dd(n), and the uncorrected duty ratio difference during downward rotation is denoted by ΔDd(n). The uncorrected duty ratio difference ΔDd(n) during downward rotation is a value obtained by subtracting the ideal duty ratio D(n) from the uncorrected duty ratio Dd(n) during downward rotation. Further, the actual step during downward rotation without correction is referred to as "substantially uncorrected step during downward rotation" and represented by Sd(n). The difference obtained by subtracting the actual step Sd(n) from the indicated step n during downward rotation is referred to as the "non-correction step difference during downward rotation" and is expressed as ΔSd(n).

At step 147 shown on the upper horizontal axis, a balanced state is reached with a small drive torque as shown in FIG. After that, the descending rotation is continued with a constant delay. For example, the uncorrected duty ratio difference ΔDd (146) during downward rotation in step 146 is j. The uncorrected actual step Sd (146) during downward rotation is 145, and the uncorrected step difference ΔSd (146) during downward rotation is 1 calculated from 146-145.

When both upward rotation and downward rotation are performed, the uncorrected duty ratio Du(n) during upward rotation and the uncorrected duty ratio Dd(n) during downward rotation are obtained for step n. For example, for step 106, Du (106) is i+j and Dd (106) is i+7j. Du(n) and Dd(n) specify the uncorrected duty ratio difference ΔDu(n) during upward rotation and the uncorrected duty ratio difference ΔDd(n) during downward rotation. Further, the uncorrected step difference ΔSu(n) during upward rotation and the uncorrected step difference ΔSd(n) during downward rotation are specified. ΔSd(n) is represented by Equation 5 below.
ΔSd(n)=ΔDd(n)/U [Formula 5]

Focusing on the ideal duty ratio D(108)=i+8j in the illustrated step 108, the duty ratio at that level appears at step 113 during upward rotation and at step 107 during downward rotation. In other words, there is a difference in steps showing the same mechanical angle during upward rotation and during downward rotation. This step width can be identified by the sum of the uncorrected step difference ΔSd (107) during downward rotation and the uncorrected step difference ΔSu (113) during upward rotation. Such step openings occur at other levels as well. In FIG. 14, the dashed-dotted line indicates the center line connecting the center points of the step openings. In the present embodiment, as indicated by the white arrows, the correction shifts the entire non-correction duty ratios Du(n) and Dd(n) so that the center line overlaps the line of the ideal duty ratio D(n). I do. In terms of the graph, the center line is slid to the left with half of ΔSu(113)−ΔSd(107) as the amount of movement. The behavior when the excitation pattern is corrected will be described later with reference to FIG. equalize. If the duty ratio difference with correction during downward rotation is expressed as ΔDd'(n), ΔSd'(n) is expressed by the following equation 6.
ΔSd′(n)=ΔDd′(n)/U [Formula 6]

As processing, a correction value is determined so as to reduce the excitation pattern corresponding to each step by an amount corresponding to the amount of movement of the step. In this example, the excitation pattern correction value matches the step movement amount. In this example, the amount of movement of the step and the correction value of the excitation pattern are both -2.

Then, the excitation pattern correction value ΔRp is obtained by Equation 7 below.
ΔRp=−(Representative value of ΔSu−Representative value of ΔSd)/2 [Formula 7]
Note that the uncorrected step difference ΔSu(n) during upward rotation is calculated from ΔDu(n) according to Equation (1). Further, the uncorrected step difference ΔSd(n) during downward rotation is calculated from ΔDd(n) according to Equation (5).

The representative value of the uncorrected step difference ΔSu during upward rotation is the representative value of ΔSu(n) of the sample during upward rotation. The type of representative value is, for example, the minimum value. Other examples may be the maximum value, average value, median value, mode value, or the like. The representative value of the uncorrected step difference ΔSd during downward rotation is the representative value of the sample ΔSd(n) during downward rotation. The type of representative value is, for example, the maximum value. Other examples include minimum value, average value, median value, or mode value. In this example, the representative value of ΔSu is 5, the representative value of ΔSd is 1, and the excitation pattern correction value ΔRp is -2.

FIG. 15 is a diagram showing an example of parameters during upward rotation without correction.
It shows the parameters for the samples from step 100 to step 153 in upward rotation. This example corresponds to FIG. Step n is specified in the control circuit. The uncorrected excitation pattern Rp(n) is determined by the correspondence with step n. The ideal duty ratio D(n) is determined by the uncorrected excitation pattern Rp(n). That is, the ideal duty ratio D(n) is logically determined from step n. The uncorrected duty ratio Du(n) during upward rotation is output from the magnetic sensor 119 . Note that this duty ratio Du(n) is a value based on actual operation and measurement, and therefore includes some variations.

Although omitted in FIG. 15, the uncorrected excitation pattern Rp (137) in step 137 is k+10. Similarly, the uncorrected excitation pattern Rp (138) is k+9, the uncorrected excitation pattern Rp (139) is k+8, the uncorrected excitation pattern Rp (140) is k+7, and the uncorrected excitation pattern Rp (141) is k+6. These values are shown in the upper left part of FIG. Values k+10 to k+6 should be shown below k+44 to k+35, but are shown above for convenience of the size of the graph.

The uncorrected duty ratio difference ΔDu(n) during upward rotation is determined by subtracting the uncorrected duty ratio Du(n) during upward rotation from the ideal duty ratio D(n). Although ΔDu(n) is almost constant, some variations may appear. The uncorrected step difference ΔSu(n) during upward rotation is calculated from ΔDu(n) according to Equation (1). Although ΔSu(n) is almost constant, some variations may appear. The uncorrected actual step Su(n) at the time of upward rotation is specified by step n-uncorrected step difference ΔSu(n). Su(n) may contain some variation. The uncorrected real step Su(n) need not be calculated although it is shown in FIG. 15 for convenience of explanation.

FIG. 16 is a diagram showing an example of parameters during downward rotation without correction.
The parameters for the samples from step 148 to step 99 in downward rotation are shown. This example corresponds to FIG. Step n, uncorrected excitation pattern Rp(n) and ideal duty ratio D(n) are the same as in FIG.

The uncorrected duty ratio Dd(n) during downward rotation is output from the magnetic sensor 119 . It should be noted that the duty ratio Dd(n) includes some variations like Du(n). The uncorrected duty ratio difference ΔDd(n) during downward rotation is determined by subtracting the ideal duty ratio D(n) from the uncorrected duty ratio Dd(n) during downward rotation. .DELTA.Dd(n) may show some variation like .DELTA.Du(n). The uncorrected step difference ΔSd(n) during downward rotation is calculated from ΔDd(n) according to Equation (5). As with ΔSu(n), ΔSd(n) may show some variation. The actual uncorrected step Sd(n) during downward rotation is specified by step n+uncorrected step difference ΔSd(n). Sd(n) may contain some variation like Su(n). The uncorrected real step Sd(n), like Su(n), is shown in FIG. 16 for convenience of explanation, but need not be calculated.

The sample data includes step n and uncorrected duty ratio Du(n) during upward rotation shown in FIG. 15 and step n and uncorrected duty ratio Dd(n) during downward rotation shown in FIG. Other parameters shown in FIGS. 15 and 16 can be calculated in the course of sample data collection processing or excitation pattern correction value calculation processing. The calculated parameters may be included in the sample data for convenience of processing.

FIG. 17 is a graph for explaining the result of excitation pattern correction.
Similar to FIG. 13, it shows the behavior in the case of upward rotation and the downward rotation in the corrected state. This behavior is exhibited when using a regulated motor operated valve 1 . As described with reference to FIG. 13, the drive current is applied by the corrected excitation pattern Rp'(n) indicated by the white circle, and the motor unit 3 is driven.

The center line of the corrected duty ratio Du'(n) during upward rotation and the corrected duty ratio Dd'(n) during downward rotation overlaps the line of the ideal duty ratio D(n). Compared to the case where correction is not performed, at step 106, for example, the excitation pattern without correction Rp(106)=k+41 is changed to the excitation pattern with correction Rp'(106)=k+39. k is an integer constant. Accordingly, the uncorrected duty ratio Du(106)=i+j shifts to the corrected duty ratio Du'(106)=i+3j, and the uncorrected duty ratio Dd(106)=i+7j changes to the corrected duty ratio Dd'(106 )=i+9j. As a result, the uncorrected duty ratio difference ΔDu (106)=5j during upward rotation changes to the corrected duty ratio difference ΔDu′ (106)=3j during upward rotation, and the uncorrected duty ratio difference ΔDd ( 106)=j changes to the corrected duty ratio difference .DELTA.Dd' (106)=3j during downward rotation.

As described above, without correction, the duty ratio difference ΔDu is large during upward rotation, and the angle error of the rotor 60 is large. An angular error of the rotor 60 is reduced.

FIG. 18 is a diagram showing an example of parameters during upward rotation with correction.
The parameters for the samples from step 100 to step 151 in upward rotation with correction are shown. This example corresponds to FIG. Step n and uncorrected excitation pattern Rp(n) are the same as in FIG. The excitation pattern correction value ΔRp is a constant value. The corrected excitation pattern Rp'(n) is obtained according to Equation (2). The corrected duty ratio Du′(n) during upward rotation is a value output from the magnetic sensor 119 . As shown in Equation 3, the corrected duty ratio difference ΔDu'(n) during upward rotation is the difference obtained by subtracting the corrected duty ratio Du'(n) during upward rotation from the ideal duty ratio D(n). identified. The corrected step difference ΔSu'(n) during upward rotation is calculated from ΔDu'(n) according to Equation (4).

Although omitted in FIG. 18, the corrected excitation pattern Rp' (137) in step 137 is k+8. Similarly, the corrected excitation pattern Rp' (138) is k+7, and the non-corrected excitation pattern Rp (139) is k+6. These values are shown in the upper left part of FIG. As in the case of FIG. 14, k+10 to k+6 are values that should be shown below k+44 to k+35, but are shown above for convenience of the size of the graph.

FIG. 19 is a diagram showing an example of parameters during downward rotation with correction.
The parameters for the samples from step 148 to step 97 in downward rotation with correction are shown. This example corresponds to FIG. Step n and uncorrected excitation pattern Rp(n) are the same as in FIG. As described above, the excitation pattern correction value ΔRp is a constant value, and the excitation pattern with correction Rp′(n) is obtained according to Equation (2). The corrected duty ratio Dd′(n) during downward rotation is a value output from the magnetic sensor 119 . The corrected duty ratio difference ΔDd'(n) during downward rotation is specified as the difference obtained by subtracting the ideal duty ratio D(n) from the corrected duty ratio Dd'(n) during downward rotation. The corrected step difference ΔSd′(n) during downward rotation is specified according to Equation (6).

FIG. 20 is a functional block diagram of the adjusting device 300 and the electric valve control device 200. As shown in FIG.
In this embodiment, the adjustment device 300 connected to the motor-operated valve control device 200 at the manufacturing stage obtains the excitation pattern correction value and sets it in the motor-operated valve control device 200 . Since the excitation pattern correction value suitable for each individual motor-operated valve control device 200 is determined, it is possible to make adjustments suitable for different conditions such as drive torque and load torque for each individual motor-operated valve 1 . The reason why the magnitude of the driving torque differs for each individual is that the magnitude of the magnetic force generated by the coil 73 of the stator 64 varies as described above. In addition, the reason why the magnitude of the load torque differs for each individual is that there is variation in the magnitude of the frictional force and the rotational force generated in the threaded portion. This is caused by variation in the shape of the threaded portion, variation in the magnitude of the elastic force of the spring 46, and the like. However, if the adjustment suitable for each individual product is performed in this way, it will lead to the stabilization of the quality of mass-produced products. Since the problem can be dealt with without setting the quality level of the parts of the motor-operated valve 1 to a high level, it also contributes to the reduction of the parts cost.

Each component of the adjustment device 300 includes computing units such as a CPU (Central Processing Unit) and various coprocessors, storage devices such as memory and storage, hardware including wired or wireless communication lines connecting them, and storage devices. It is implemented by software that is stored and provides processing instructions to the calculator. A computer program may consist of a device driver, an operating system, various application programs located in their higher layers, and a library that provides common functions to these programs. Each illustrated block does not represent a configuration in units of hardware, but represents blocks in units of function.

Coordinator 300 includes data processing unit 302 , communication unit 304 and data storage unit 306 . A communication unit 304 is in charge of communication processing via a communication path connected to the motor-operated valve control device 200 . A data storage unit 306 stores various data. The data processing unit 302 executes various processes based on data acquired by the communication unit 304 and data stored in the data storage unit 306 . Data processing unit 302 also functions as an interface for communication unit 304 and data storage unit 306 .

Communication unit 304 includes a transmitting unit 312 for transmitting data and commands and a receiving unit 310 for receiving data.

The data processing unit 302 has an instruction unit 318 , a sample acquisition unit 320 , a correction value calculation unit 322 and a correction value setting unit 324 . The instruction unit 318 issues various instructions to the motor-operated valve control device 200, such as searching for the origin. The sample acquisition section 320 acquires sample data from the electric valve control device 200 . A correction value calculator 322 calculates an excitation pattern correction value ΔRp based on the sample data. A correction value setting unit 324 sets an excitation pattern correction value ΔRp in the electric valve control device 200 .

The data storage unit 306 has a sample data storage unit 330 that stores sample data.

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 data storage section 206 and a rotor interface section 208 .
The communication unit 204 functions as an interface to an external device or adjustment device via the connection terminal 81 . Rotor interface section 208 functions as an interface for magnetic sensor 119 and coil unit 75 . The data processing unit 202 executes various processes based on data stored in the data storage unit 206 and various data acquired from the communication unit 204 and the rotor interface unit 208 . Data processing unit 202 also functions as an interface for communication unit 204 , rotor interface unit 208 and data storage unit 206 .

The communication unit 204 includes a receiving unit 210 for receiving data and commands from an external device or coordinating device, and a transmitting unit 212 for transmitting data to the external device or coordinating 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 from the current pulse received from the magnetic sensor 119 .

The data processing section 202 includes a rotation control section 218 . The rotation control section 218 controls the rotation instruction section 214 based on the origin information (reference information), the excitation pattern correction value, and the like.

Data storage unit 206 includes reference information storage unit 220 and excitation pattern correction value storage unit 222 . The reference information storage unit 220 stores origin information (reference information). The excitation pattern correction value storage unit 222 stores an excitation pattern correction value ΔRp. The reference information storage unit 220 and the excitation pattern correction value storage unit 222 are storage areas configured in a non-volatile memory.

FIG. 21 is a sequence diagram showing the adjustment process.
Adjustment processing is performed, for example, in the final stage of manufacturing. Therefore, it is assumed that the assembly of the electric valve control device 200 has been completed.

The instruction unit 318 of the adjustment device 300 instructs the motor-operated valve control device 200 to search for the origin (S10). At this time, an origin search command is transmitted from the transmission unit 312 of the adjustment device 300 . According to this command, the motor-operated valve control device 200 performs an origin search operation for aligning the valve body 34 with the origin position, and returns the duty ratio D(0) and the excitation pattern Rp(0) of step 0 to the adjustment device 300 ( S12). After that, the adjustment device 300 identifies the excitation pattern Rp(n) at each step n and the ideal duty ratio D(n) based on the duty ratio D(0) and the excitation pattern Rp(0) of step 0. and so on.

The instruction unit 318 of the adjustment device 300 acquires sample data in the range of step n corresponding to the valve open state. In this example, the switching of step n is sequentially instructed to obtain the uncorrected duty ratios Du(n) and Dd(n) at step n.

For example, in sampling the upward rotation, the transmission unit 312 of the adjusting device 300 transmits a switching command to step 100, a switching command to step 101, . S14, S18, S22). As a result, the receiving unit 310 of the adjustment device 300 receives the non-correction duty ratio Du(100) in step 100, the non-correction duty ratio Du(101) in step 101, . The duty ratio Du (153) is received (S16, S20, S24). The instruction unit 318 associates the step n with the uncorrected duty ratio Du(n) and stores them in the sample data storage unit 330 .

Similarly, in the downward rotation sampling, the transmitter 312 of the adjusting device 300 transmits a switching command to step 152, . The receiving unit 310 of the adjusting device 300 receives the uncorrected duty ratio Dd(152) of step 152, . The instruction unit 318 associates the step n with the uncorrected duty ratio Dd(n) and stores them in the sample data storage unit 330 .

The correction value calculator 322 executes excitation pattern correction value calculation processing based on the sample data (S34). The excitation pattern correction value calculation process will be described later with reference to FIG. After completing the excitation pattern correction value calculation process, the correction value setting unit 324 sets the excitation pattern correction value ΔRp in the electric valve control device 200 . Specifically, the transmission unit 312 transmits a correction value write command to which the excitation pattern correction value ΔRp is added to the electric valve control device 200 (S36). The electric valve control device 200 stores the excitation pattern correction value ΔRp according to this command.

FIG. 22 is a flow chart showing the process of the electric valve control device 200. As shown in FIG.
The processing of the electric valve control device 200 related to the adjustment processing process shown in FIG. 21 will be described in detail. When the receiving unit 210 receives the origin search command (Y of S50), the rotation control unit 218 rotates the motor unit 3 downward until the stopper 90 abuts on the protrusion of the guide member 36 to step 0 (origin ) is specified (S52). In this state, the rotation detector 216 reads the duty ratio D(0) from the pulse received from the magnetic sensor 119 (S54). The transmission unit 212 transmits the duty ratio D(0) of step 0 and the excitation pattern Rp(0) to the adjustment device 300 (S56).

When the receiving unit 210 receives the command to switch to step n (Y of S58), the rotation control unit 218 advances the step one by one until step n. Here, it is assumed that a switching command is received for each step. The rotation control unit 218 identifies the excitation pattern Rp(n) corresponding to the step n for which the switch has been instructed (S60). The rotation instruction unit 214 changes the value of the drive current according to the excitation pattern (S62). After changing the drive current value, the rotation detector 216 reads the duty ratio D(n) from the pulse received from the magnetic sensor 119 (S64). The transmission unit 212 transmits the read duty ratio D(n) of step n to the adjusting device 300 (S66).

When the receiving unit 210 receives the correction value write command to which the excitation pattern correction value ΔRp is added (Y in S68), the rotation control unit 218 replaces the excitation pattern correction value ΔRp added to the write command with the excitation pattern correction value. It is stored in the storage unit 222 (S70).

FIG. 23 is a flow chart showing the excitation pattern correction value calculation process.
The correction value calculator 322 of the adjustment device 300 identifies the uncorrected excitation pattern Rp(n) corresponding to the step n of each sample with reference to the excitation pattern Rp(0) (S80). In this example, it is assumed that the uncorrected excitation pattern Rp(n) of each sample is stored in the sample data.

The correction value calculator 322 identifies the ideal duty ratio D(n) corresponding to the uncorrected excitation pattern Rp(n) of each sample (S82). In this example, it is assumed that the ideal duty ratio D(n) of each sample is stored in the sample data.

The processes of S80 and S82 described above are commonly performed for each sample during upward rotation and each sample during downward rotation. The following processing of S84 to S88 is performed for each sample during upward rotation.

The correction value calculation unit 322 subtracts the uncorrected duty ratio Du(n) during upward rotation from the ideal duty ratio D(n) for each sample during upward rotation to obtain the uncorrected duty ratio difference ΔDu during upward rotation. (n) is calculated (S84). In this example, the uncorrected duty ratio difference ΔDu(n) during upward rotation of each sample during upward rotation is stored in the sample data. The correction value calculation unit 322 identifies a representative value of the uncorrected duty ratio difference ΔDu(n) in samples during upward rotation (S86). In this example, the correction value calculator 322 identifies the minimum value of the uncorrected duty ratio difference ΔDu(n) during upward rotation. The correction value calculation unit 322 may specify the maximum value, average value, median value, mode value, or the like of the uncorrected duty ratio difference ΔDu(n) during upward rotation. The correction value calculator 322 calculates a representative value of the uncorrected step difference ΔSu(n) during upward rotation in each sample during upward rotation (S88). A representative value of the uncorrected step difference ΔSu(n) during upward rotation is calculated according to Equation (1).

Subsequently, the correction value calculator 322 performs the processes of S90 to S94 on the samples in the downward rotation process.
The correction value calculator 322 subtracts the ideal duty ratio D(n) from the uncorrected duty ratio Dd(n) for the downward rotation for each sample for the downward rotation, and obtains the uncorrected duty ratio difference ΔDd for the downward rotation. (n) is calculated (S90). In this example, the uncorrected duty ratio difference ΔDd(n) during downward rotation of each sample during downward rotation is stored in the sample data. The correction value calculation unit 322 identifies a representative value of the uncorrected duty ratio difference ΔDd(n) in samples during downward rotation (S92). In this example, the correction value calculator 322 identifies the maximum value of the uncorrected duty ratio difference ΔDd(n) during downward rotation. The correction value calculator 322 may specify the minimum value, average value, median value, mode value, or the like of the uncorrected duty ratio difference ΔDd(n) during downward rotation. The correction value calculator 322 calculates a representative value of the uncorrected step difference ΔSd(n) during downward rotation in each sample during downward rotation (S94). A representative value of the uncorrected step difference ΔSd(n) during downward rotation is calculated according to Equation (5).

The correction value calculator 322 calculates the excitation pattern correction value ΔRp according to Equation 7 (S96). In order to make the excitation pattern correction value ΔRp an integer, the correction value calculation unit 322 performs processing such as rounding off, rounding down, and rounding up to the decimal point of the calculation result of Equation 7. FIG.

FIG. 24 is a flow chart showing the process of the electric valve control device 200. As shown in FIG.
Here, the process at the stage of using the electric valve control device 200 in which the excitation pattern correction value ΔRp is set will be described.

When the receiving unit 210 receives the movement command from the external device (Y of S100), the rotation control unit 218 determines the rotation direction and rotation speed according to the movement command (S102). The rotation control unit 218 determines whether or not to advance the step now according to the rotation direction and rotation speed (S104). When advancing the step (Y of S104), the rotation control unit 218 specifies the next step n according to the rotation direction (S106). The rotation control unit 218 identifies the non-correction excitation pattern Rp(n) of the next step n according to the correspondence relationship between the step n and the non-correction excitation pattern (S108). The rotation control unit 218 corrects the excitation pattern (S110). Specifically, the rotation control unit 218 adds the excitation pattern correction value ΔRp read from the excitation pattern correction value storage unit 222 to the non-correction excitation pattern Rp(n) in accordance with Equation 2 to obtain the excitation pattern with correction Rp′( n) is calculated. At that time, if the rotation instructing section 214 is turned off, the rotation control section 218 turns on the rotation instructing section 214 . Further, the rotation control unit 218 instructs the rotation instruction unit 214 to apply the excitation pattern with correction Rp'(n), and the rotation instruction unit 214 changes the drive current to a value corresponding to the excitation pattern with correction Rp'(n). (S112). That is, the drive current corresponding to the corrected excitation pattern Rp′(n) is applied to the motor unit 3 .

When the reception unit 210 receives the stop command (Y of S114), the rotation control unit 218 turns off the power supply to the rotation instruction unit 214 (S116). As a result, as shown in FIG. 9A, the valve is stopped and the attitude of the rotor 60 is maintained.

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 constituent elements may be deleted from all the constituent elements shown in the above embodiments and modifications.

[Modification 1]
In this embodiment, the center line of the corrected duty ratio Du'(n) during upward rotation and the corrected duty ratio Dd'(n) during downward rotation is superimposed on the line of the ideal duty ratio D(n). , the uncorrected duty ratios Du(n) and Dd(n) are all shifted. On the graph of FIG. 14, the center line is slid to the left with half of ΔSu(113)−ΔSd(107) as the amount of movement. As a modification, the center line may be brought closer to the line of the ideal duty ratio D(n) without overlapping. In terms of the graph of FIG. 14, a width smaller than half of ΔSu(113)−ΔSd(107) may be used as the amount of movement. In that case, ΔRp is calculated by Equation 8.
ΔRp=−(Representative value of ΔSu−Representative value of ΔSd)/V [Formula 8]
Constant V is a value greater than two. For example, the value is 2<V≦4.

[Modification 2]
In the embodiment, an example of obtaining a common excitation pattern correction value ΔRp for upward rotation and downward rotation has been shown, but different excitation pattern correction values may be obtained for upward rotation and downward rotation.

The excitation pattern correction value during upward rotation is represented as ΔRpu. For example, the non-correction duty ratio Du(n) is shifted so that the duty ratio Du'(n) with correction during upward rotation overlaps the line of the ideal duty ratio D(n). In that case, ΔRpu is calculated by Equation (9).
Representative value of ΔRpu = -ΔSu [Formula 9]
Note that the uncorrected step difference ΔSu(n) during upward rotation is calculated from ΔDu(n) according to Equation (1). In this example, the representative value of ΔSu is 5, and the excitation pattern correction value ΔRp during upward rotation is -5. As a result, five excitation patterns precede at the time of upward rotation.

The excitation pattern correction value during downward rotation is represented as ΔRpd. For example, the non-correction duty ratio Dd(n) is shifted so that the duty ratio Dd'(n) with correction during downward rotation overlaps the line of the ideal duty ratio D(n). In that case, ΔRpd is calculated by Equation (10).
ΔRpd = representative value of ΔSd [Formula 10]
The uncorrected step difference ΔSd(n) during downward rotation is calculated from ΔDd(n) according to Equation (5). In this example, the representative value of ΔSd is 1, and the excitation pattern correction value ΔRpd during downward rotation is 1. As a result, one excitation pattern precedes the downward rotation.

The operation in modification 2 will be supplemented based on the embodiment.
21, when the excitation pattern correction value calculation process is completed, the correction value setting unit 324 sets the excitation pattern correction value ΔRpu for upward rotation and the excitation pattern correction value ΔRpd for downward rotation to the electric valve control device 200. set. Specifically, the transmission unit 312 transmits a correction value write command to which the excitation pattern correction value ΔRpu for upward rotation and the excitation pattern correction value ΔRpd for downward rotation are added to the electric valve control device 200 (S36). . According to this command, the electric valve control device 200 stores an excitation pattern correction value ΔRpu for upward rotation and an excitation pattern correction value ΔRpd for downward rotation.

22, when the receiving unit 210 receives a correction value write command to which the excitation pattern correction value ΔRpu for upward rotation and the excitation pattern correction value ΔRpd for downward rotation are added (Y in S68), rotation control is performed. The unit 218 causes the excitation pattern correction value storage unit 222 to store the excitation pattern correction value ΔRpu for upward rotation and the excitation pattern correction value ΔRpd for downward rotation added to the write command (S70).

24, in the excitation pattern correction shown in S110, in the case of upward rotation, the rotation control unit 218 stores the uncorrected excitation pattern Rp(n) in the excitation pattern correction value storage unit 222 according to Equation 11. is added to the excitation pattern correction value ΔRpu at the time of the upward rotation read from , the excitation pattern with correction Rp′(n) is calculated.
Rp′(n)=Rp(n)+ΔRpu [Formula 11]

In the case of downward rotation, the rotation control unit 218 adds the excitation pattern correction value ΔRpd for downward rotation read from the excitation pattern correction value storage unit 222 to the non-corrected excitation pattern Rp(n) in accordance with Equation 12 to perform correction. Then, an excitation pattern Rp'(n) is calculated.
Rp′(n)=Rp(n)+ΔRpd [Formula 12]

[Modification 3]
In the above-described embodiment, modified example 1, and modified example 2, an example is shown in which the process of calculating the excitation pattern correction value is performed by the adjustment device 300 connected to the motor-operated valve control device 200 of the motor-operated valve 1, but these excitation patterns The process of calculating the correction value may be performed on the motor operated valve 1 side. That is, it is possible to provide the motor-operated valve control device 200 on the circuit board 118 with the function of the adjusting device 300 and calculate the excitation pattern correction value only with the motor-operated valve 1 .

FIG. 25 is a functional block diagram of an electric valve control device 200 according to Modification 2. As shown in FIG.
The data processing section 202 of the electric valve control device 200 has a sample generation section 219 and a correction value calculation section 322 .
The sample generation unit 219 generates sample data equivalent to the sample data acquired by the adjustment device 300 described in the embodiment, modification 1, and modification 2. FIG. The correction value calculator 322 calculates the excitation pattern correction value ΔRp based on the sample data, as in the case of the adjustment device 300 shown in the embodiment and modification 1. FIG. Alternatively, the correction value calculation unit 322 calculates the excitation pattern correction value ΔRpu for upward rotation and the excitation pattern correction value ΔRpd for downward rotation based on sample data, as in the case of the adjustment device 300 shown in Modification 2. do.

The data storage unit 206 of the electric valve control device 200 has a sample data storage unit 330 equivalent to the sample data storage unit 330 of the adjustment device 300 shown in the embodiment, modification 1 and modification 2.

FIG. 26 is a flow chart showing the correction value setting process of the electric valve control device 200 in Modification 3. As shown in FIG.
This process is started when the receiving unit 210 of the motor-operated valve control device 200 receives a command for setting the excitation pattern correction value from the adjusting device 300 in the final stage of manufacturing. Alternatively, this process is started when the receiving unit 210 of the motor-operated valve control device 200 receives a command for setting the excitation pattern correction value from an external device while the motor-operated valve 1 is installed in, for example, an automotive air conditioner. . Also, it may be activated at a timing other than these. It is assumed that the origin searching operation has been completed.

The sample generator 219 sequentially identifies the steps in the sampling range corresponding to the valve open state (S120). Specifically, the sample generation unit 219 specifies, for example, steps 100, 101, . Further, the sample generator 219 specifies, for example, steps 152, 151, .

Rotation control unit 218 identifies excitation pattern Rp(n) corresponding to step n identified by sample generation unit 219 (S122). The rotation instruction unit 214 changes the value of the drive current according to the excitation pattern (S124). After changing the drive current value, the rotation detector 216 reads the duty ratio D(n) from the pulse received from the magnetic sensor 119 (S126). Then, the sample generator 219 adds the step n and the duty ratio D(n) to the sample data (S128).

When the sample generator 219 determines that there are remaining steps in the sampling range (steps in the upward rotation direction and steps in the downward rotation direction) (N in S130), the process returns to S120 and repeats the above-described processing. When the sample generating unit 219 determines that all the steps in the sampling range have been processed (Y of S130), the process proceeds to S132.

Thus, sample data is generated in the electric valve control device 200 . That is, by sampling the upward rotation, each step n in the upward rotation direction and the uncorrected duty ratio Du(n) at each step n are associated and stored in the sample data storage unit 330 . Further, by sampling the downward rotation, each step n in the downward rotation direction and the uncorrected duty ratio Dd(n) at each step n are stored in the sample data storage unit 330 in association with each other.

After generating the sample data, the correction value calculator 322 of the motor-operated valve control device 200 executes excitation pattern correction value calculation processing (S132). The excitation pattern correction value calculation process in Modification 3 is the same as the process performed by the correction value calculation unit 322 of the adjustment device 300 in the embodiment, Modifications 1 and 2. FIG. When the same excitation pattern correction value calculation processing as in the embodiment and modification 1 is performed, the correction value calculation unit 322 of the electric valve control device 200 stores the excitation pattern correction value ΔRp in the excitation pattern correction value storage unit 222. Let When the same excitation pattern correction value calculation processing as in Modification 2 is performed, the correction value calculation unit 322 of the motor-operated valve control device 200 calculates the excitation pattern correction value ΔRpu for upward rotation and the excitation pattern correction value for downward rotation. ΔRpd is stored in the excitation pattern correction value storage unit 222 .

Other processing of the motor-operated valve control device 200 is the same as in the case of the embodiment, the first modification, and the second modification.

In this embodiment, an example in which the origin of the lowest point is used as the reference position has been described. As a modification, the highest point may be set as the reference position. The reference position may be a reference position for driving the operating rod 32 by the rotor 60 . The reference position can be arbitrarily determined as long as it is a position where the rotation of the rotor 60 can be restricted by the stopper 90 .

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 was 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.

In each embodiment, a PM stepping motor is used as the motor unit, but a hybrid stepping motor may be used. Further, 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 motor units or six first bodies, 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.

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 data storage unit, 220 reference information storage unit, 222 excitation pattern correction value storage unit, 208 rotor interface unit, 210 reception unit, 212 transmission unit, 214 rotation instruction unit, 216 rotation detection unit, 218 rotation control unit, 219 sample generation unit, 222 excitation pattern correction value storage unit, 300 adjustment device, 302 data processing unit, 304 communication unit, 306 data storage unit, 310 reception unit, 312 transmission unit, 318 instruction unit, 320 sample acquisition unit 322 correction value calculation unit 324 correction value setting unit 330 sample data storage unit

Claims (12)

Connected to an electric valve having a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, and a mechanism that changes the rotary motion of the rotor to axial motion of the valve body,
an excitation pattern correction value storage unit that stores an excitation pattern correction value set for each individual motor-operated valve;
a rotation control unit that corrects the excitation pattern corresponding to the step based on the excitation pattern correction value;
and a rotation instruction unit that applies a drive current to the stepping motor according to the corrected excitation pattern. The electric valve control device further comprises a receiving unit that receives a correction value write command to which the excitation pattern correction value is added,
2. The electric valve control device according to claim 1, wherein the rotation control unit stores the excitation pattern correction value added to the received correction value write command in the excitation pattern correction value storage unit. A stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that converts the rotary motion of the rotor into axial motion of the valve body, a sensor that detects the angle of the rotor, and the valve. an elastic body that imparts elastic force in the axial direction of the body;
A step in an operation of rotating the rotor in a first rotation direction, which is one of the two rotation directions of the rotor in which the load torque due to the elastic force is larger, and an angle of the rotor detected by the sensor in the step a sample acquisition unit that acquires sample data including a parameter from the motor-operated valve control device;
a correction value calculation unit that calculates, based on the sample data, an excitation pattern correction value that advances the excitation pattern in the operation in the first rotation direction;
and a correction value setting unit that sets the calculated excitation pattern correction value in the electric valve control device. The sample acquisition unit further indicates, as the sample data, a step in an operation of rotating the rotor in a second direction opposite to the first direction of rotation, and the angle of the rotor detected by the sensor at the step. parameters from the motor-operated valve control device,
The correction value calculator calculates, based on the sample data, the magnitude of the rotation delay of the stepping motor in the operation in the first rotation direction and the magnitude of the rotation delay of the stepping motor in the operation in the second rotation direction. 4. The adjustment device according to claim 3, wherein the excitation pattern correction value is calculated according to a condition for making the height closer. The sample acquisition unit further indicates, as the sample data, a step in an operation of rotating the rotor in a second direction opposite to the first direction of rotation, and the angle of the rotor detected by the sensor at the step. parameters from the motor-operated valve control device,
The correction value calculation unit calculates, based on the sample data, an excitation pattern correction value that advances the excitation pattern in the operation in the second rotation direction, unlike the excitation pattern correction value in the operation in the first rotation direction. The adjusting device according to claim 3, characterized in that: A stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that converts the rotary motion of the rotor into axial motion of the valve body, a sensor that detects the angle of the rotor, and the valve. an elastic body that imparts elastic force in the axial direction of the body;
A step in an operation of rotating the rotor in a first rotation direction, which is one of the two rotation directions of the rotor in which the load torque due to the elastic force is larger, and an angle of the rotor detected by the sensor in the step a sample generation unit that generates sample data including parameters indicating
a correction value calculation unit that calculates, based on the sample data, an excitation pattern correction value that advances the excitation pattern in the operation in the first rotation direction;
and a correction value storage unit that stores the calculated excitation pattern correction value. The sample generation unit further indicates, in the sample data, a step in an operation of rotating the rotor in a second rotation direction opposite to the first rotation direction, and an angle of the rotor detected by the sensor at the step. Add parameters and
The correction value calculator calculates, based on the sample data, the magnitude of the rotation delay of the stepping motor in the operation in the first rotation direction and the magnitude of the rotation delay of the stepping motor in the operation in the second rotation direction. 7. The motor-operated valve control device according to claim 6, wherein the excitation pattern correction value is calculated according to a condition for making the height closer. The sample generation unit further indicates, in the sample data, a step in an operation of rotating the rotor in a second rotation direction opposite to the first rotation direction, and an angle of the rotor detected by the sensor at the step. Add parameters and
The correction value calculation unit calculates, based on the sample data, an excitation pattern correction value that advances the excitation pattern in the operation in the second rotation direction, unlike the excitation pattern correction value in the operation in the first rotation direction. The electric valve control device according to claim 6, characterized in that: The electric valve control device further includes a rotation control unit that corrects the excitation pattern corresponding to the step based on the excitation pattern correction value;
9. The electric valve control device according to any one of claims 6 to 8, further comprising a rotation instructing section that applies a drive current to the stepping motor according to the corrected excitation pattern. A computer connected to a motor-operated valve having a stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, and a mechanism that changes the rotational motion of the rotor into axial motion of the valve body,
a function of correcting the excitation pattern corresponding to the step based on an excitation pattern correction value set for each individual motor operated valve;
and a function of applying a drive current to the stepping motor according to the corrected excitation pattern. A stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that converts the rotary motion of the rotor into axial motion of the valve body, a sensor that detects the angle of the rotor, and the valve. a computer connectable to a motor-operated valve control device connected to a motor-operated valve having an elastic body that imparts elastic force in the axial direction of the body;
A step in an operation of rotating the rotor in a first rotation direction, which is one of the two rotation directions of the rotor in which the load torque due to the elastic force is larger, and an angle of the rotor detected by the sensor in the step a function of acquiring sample data including parameters indicating from the motor-operated valve control device;
a function of calculating, based on the sample data, an excitation pattern correction value that advances the excitation pattern in the operation in the first rotation direction;
and a function of setting the calculated excitation pattern correction value in the electric valve control device. A stepping motor that rotates a rotor by a drive current applied by an excitation pattern corresponding to a step, a mechanism that converts the rotary motion of the rotor into axial motion of the valve body, a sensor that detects the angle of the rotor, and the valve. a computer connected to a motor-operated valve having an elastic body that exerts an elastic force in the axial direction of the body;
A step in an operation of rotating the rotor in a first rotation direction, which is one of the two rotation directions of the rotor in which the load torque due to the elastic force is larger, and an angle of the rotor detected by the sensor in the step A function to generate sample data including parameters indicating
a function of calculating, based on the sample data, an excitation pattern correction value that advances the excitation pattern in the operation in the first rotation direction;
and a function of storing the calculated excitation pattern correction value.

Images