Electric valve control device, electric valve device, and electric valve control method

Abstract

The invention provides an electrically operated valve control device, an electrically operated valve device with the electrically operated valve control device and a method for controlling an electrically operated valve, which can shorten the time required for the initialization operation of the electrically operated valve and suppress noise. The electric valve control device (70) inputs a second preparation number of pulses to the stepping motor (66) to rotate the rotor (41) in the second direction (second preparation operation), and inputs a first preparation number of pulses to the stepping motor (66) to rotate the rotor in the first direction (first preparation operation). The electric valve control device (70) acquires a voltage generated in the stator by rotation of the rotor (41) in the first direction. The electric valve control device (70) sets the waveform of the voltage acquired in the first preparation operation as a reference waveform of the voltage. The electrically operated valve control device (70) determines whether or not the electrically operated valve (5) is in a rotation restriction state on the basis of the difference between the waveform of the voltage and the reference waveform of the voltage.

Description

Technical Field

[0001] The present invention relates to an electric valve control device, an electric valve device having the electric valve control device, and a control method of the electric valve. Background Art

[0002] Patent Document 1 discloses an example of a conventional electric valve. This electric valve is installed in the refrigeration cycle of an air conditioner. The electric valve comprises a valve body, a valve core, and a stepping motor for moving the valve core. The stepping motor comprises a rotor and a stator. When pulses are input to the stepping motor, the rotor rotates. The valve core moves in accordance with the rotation of the rotor. When the rotor is in a reference position, a movable stopper, which rotates with the rotor, abuts against a fixed stopper fixed to the valve body, thereby restricting the rotor's rotation in a first direction.

[0003] The electric valve is controlled by an electric valve control device. During the initialization operation, the electric valve control device inputs pulses to the stepper motor, rotating the rotor in the first direction and thereby positioning the rotor in the reference position. The number of pulses input to the stepper motor is sufficient to cause the movable stopper to abut against the fixed stopper (hereinafter referred to as the "initialization number"). When the rotor rotates in the first direction and the movable stopper abuts against the fixed stopper, the rotor is positioned in the reference position.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2019 / 130928

[0007] Technical problem to be solved by the invention

[0008] The electric valve control device continues to input pulses to the stepper motor until the number of pulses input to the stepper motor reaches the initialization number. Therefore, the electric valve control device may input pulses even after the rotor is positioned at the reference position, causing the initialization process to take a long time. Furthermore, when pulses are input to the stepper motor after the rotor is positioned at the reference position, the movable stopper repeatedly collides with the fixed stopper, generating noise. This noise is particularly pronounced if the rotor is close to the reference position immediately before initialization. Summary of the Invention

[0009] Therefore, an object of the present invention is to provide a motor-driven valve control device, a motor-driven valve device including the motor-driven valve control device, and a method for controlling a motor-driven valve, which can shorten the time required for initialization of the motor-driven valve and suppress noise.

[0010] Technical means for solving technical problems

[0011] The inventors of this application used multiple electric valves to measure the voltage generated in the stator by the rotation of the rotor during initialization (the voltage resulting from electromagnetic induction in the stator) and conducted in-depth research on the measurement results. As a result, the inventors discovered that the voltage waveform before the rotor's rotation was restricted by the stop mechanism differed from the voltage waveform after the rotor's rotation was restricted by the stop mechanism. Furthermore, the inventors discovered that the voltage waveform immediately after the electric valve, in a cold state, began to operate differed from the voltage waveform after the operation progressed and the electric valve temperature increased, and that the voltage waveform stabilized as the electric valve heated up. This discovery led to the present invention.

[0012] To achieve the above-mentioned object, an electric valve control device according to one embodiment of the present invention controls an electric valve, the electric valve comprising: a valve body having a valve port; a stepping motor having a rotor and a stator; a valve core facing the valve port and moving toward the valve port when the rotor rotates in a first direction; and a stopper mechanism that restricts rotation of the rotor in the first direction when the rotor is in a reference position, wherein:

[0013] a rotation control unit that inputs pulses to the stepping motor to rotate the rotor;

[0014] a voltage acquisition unit configured to acquire a voltage generated on the stator by the rotor rotating in the first direction;

[0015] a state determination unit that determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted based on a difference between the waveform of the voltage and a reference waveform of the voltage; and

[0016] a reference waveform setting unit that sets a reference waveform of the voltage,

[0017] The rotation control unit performs a second preparatory operation of inputting a second preparatory number of pulses to the stepping motor to rotate the rotor in a second direction. Following the second preparatory operation, the rotation control unit performs a first preparatory operation of inputting a first preparatory number of pulses less than the second preparatory number to the stepping motor to rotate the rotor in the first direction.

[0018] The reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation as a reference waveform of the voltage.

[0019] In the present invention, it is preferred that:

[0020] When the rotation control unit starts the first preparatory operation, the voltage reference waveform has not yet been set.

[0021] After the reference waveform setting unit sets the reference waveform of the voltage, the state determination unit starts a determination operation of determining whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation is similar to the reference waveform of the voltage.

[0022] If the number of pulses input to the stepping motor in the first preparatory operation reaches K, the reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit as the reference waveform of the voltage.

[0023] When the state determination unit determines in the determination operation that the waveform of the voltage is similar to the reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the reference waveform of the voltage.

[0024] When the state determination unit determines in the determination operation that the waveform of the voltage is not similar to the reference waveform of the voltage, the reference waveform setting unit maintains the reference waveform of the voltage.

[0025] Here, K is a natural number greater than 1.

[0026] In the present invention, it is preferred that:

[0027] Following the first preparatory operation, the rotation control unit performs a positioning operation of inputting a pulse to the stepping motor to rotate the rotor in the first direction.

[0028] The state determination unit performs the determination operation of determining whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation and the positioning operation is similar to a reference waveform of the voltage.

[0029] In the present invention, it is preferred that:

[0030] The state determination unit calculates a difference index value indicating the degree of difference between the voltage waveform and the voltage reference waveform in the determination operation, and determines whether the voltage waveform is similar to the voltage reference waveform based on a comparison result of the difference index value and a similarity determination value.

[0031] In the present invention, it is preferred that:

[0032] The voltage reference waveform is a data table that associates a time with a reference voltage at that time, which is set for a first direction pulse. The first direction pulse is a pulse input to the stepping motor to rotate the rotor in the first direction.

[0033] When the first direction pulse is input to the stepping motor, the voltage acquisition unit acquires the voltage in a time series manner.

[0034] If the voltage acquisition unit acquires the voltage at an acquisition time corresponding to the input of the first direction pulse, the state determination unit calculates an intermediate value, the intermediate value being a value obtained by squaring a difference between the voltage and the reference voltage, the reference voltage being a voltage associated with the time corresponding to the acquisition time in the data table set for the first direction pulse input to the stepping motor.

[0035] The state determination unit calculates the difference index value by adding a plurality of intermediate values ​​calculated using the voltage acquired by the voltage acquisition unit in response to input of the first direction pulse.

[0036] In the present invention, it is preferred that:

[0037] The state determination unit calculates the difference index value by adding a plurality of intermediate values ​​calculated using the voltage acquired by the voltage acquisition unit during a portion of a period from the beginning to the end of the first direction pulse.

[0038] A voltage component related to the back electromotive force caused by the inductance of the stator included in the voltage during a portion of the period is smaller than a voltage component related to the electromagnetic induction caused by the rotation of the rotor included in the voltage.

[0039] In the present invention, it is preferred that:

[0040] When the rotation control unit starts the first preparatory operation, the first reference waveform of the voltage and the second reference waveform of the voltage have not yet been set.

[0041] After the reference waveform setting unit sets the first reference waveform of the voltage, the state determination unit starts a first determination operation to determine whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation is similar to the first reference waveform of the voltage.

[0042] After the reference waveform setting unit sets the second reference waveform of the voltage, the state determination unit starts a second determination operation, the second determination operation determining whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation is similar to the second reference waveform of the voltage.

[0043] If the number of pulses input to the stepping motor in the first preparatory operation reaches K, the reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit as the first reference waveform of the voltage.

[0044] When the state determination unit determines in the first determination operation that the waveform of the voltage is similar to the first reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the first reference waveform of the voltage.

[0045] When the state determination unit determines in the first determination operation that the waveform of the voltage is not similar to the first reference waveform of the voltage, the reference waveform setting unit maintains the first reference waveform of the voltage.

[0046] When the state determination unit determines for the first time in the first determination operation that the waveform of the voltage is not similar to the first reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination to the second reference waveform of the voltage.

[0047] When the state determination unit determines in the second determination operation that the waveform of the voltage is similar to the second reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the second reference waveform of the voltage.

[0048] When the state determination unit determines in the second determination operation that the waveform of the voltage is not similar to the second reference waveform of the voltage, the reference waveform setting unit maintains the second reference waveform of the voltage.

[0049] When the first preparatory operation is completed, the reference waveform setting unit sets the first reference waveform of the voltage as the reference waveform of the voltage when the number of times the voltage waveform is set to the first reference waveform of the voltage is greater than the number of times the voltage waveform is set to the second reference waveform of the voltage, and sets the second reference waveform of the voltage as the reference waveform of the voltage when the number of times the voltage waveform is set to the second reference waveform of the voltage is greater than the number of times the voltage waveform is set to the first reference waveform of the voltage.

[0050] Here, K is a natural number greater than 1.

[0051] In the present invention, it is preferred that:

[0052] Following the first preparatory operation, the rotation control unit performs a positioning operation of inputting a pulse to the stepping motor to rotate the rotor in the first direction.

[0053] When the positioning operation starts, the state determination unit starts a determination operation for determining whether the waveform of the voltage acquired by the voltage acquisition unit during the positioning operation is similar to a reference waveform of the voltage.

[0054] When the state determination unit determines in the determination operation that the waveform of the voltage is similar to the reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the reference waveform of the voltage.

[0055] When the state determination unit determines in the determination operation that the waveform of the voltage is not similar to the reference waveform of the voltage, the reference waveform setting unit maintains the reference waveform of the voltage.

[0056] In the present invention, it is preferred that:

[0057] When the state determination unit determines that the waveform of the voltage is similar to the first reference waveform of the voltage in the first determination action and determines that the waveform of the voltage is similar to the second reference waveform of the voltage in the second determination action, (1) when the waveform of the voltage used for the determination is more similar to the first reference waveform of the voltage than to the second reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination to the first reference waveform of the voltage, and (2) when the waveform of the voltage used for the determination is more similar to the second reference waveform of the voltage than to the first reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination to the second reference waveform of the voltage.

[0058] In the present invention, it is preferred that:

[0059] In the first determination operation, the state determination unit calculates a first difference index value indicating the degree of difference between the waveform of the voltage and a first reference waveform of the voltage, and determines whether the waveform of the voltage is similar to the first reference waveform of the voltage based on a comparison result of the first difference index value and a similarity determination value.

[0060] In the second determination operation, the state determination unit calculates a second difference index value indicating the degree of difference between the waveform of the voltage and a second reference waveform of the voltage, and determines whether the waveform of the voltage is similar to the second reference waveform of the voltage based on a comparison result of the second difference index value and the similarity determination value.

[0061] In the present invention, it is preferred that:

[0062] The rotation control unit performs the second preparatory operation and the first preparatory operation multiple times.

[0063] The reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit in the last first preparatory operation as the reference waveform of the voltage.

[0064] In the present invention, it is preferred that:

[0065] Following the first preparatory operation, the rotation control unit performs a positioning operation of inputting a pulse to the stepping motor to rotate the rotor in the first direction.

[0066] When the state determination unit determines that the electric valve is in the first rotation restricted state during the positioning operation, the rotation control unit stops inputting pulses to the stepping motor.

[0067] The state determination unit determines that the electric valve has failed when the number of pulses input to the stepping motor in the first preparatory operation and the positioning operation exceeds an initialization number that is sufficient to position the rotor to the reference position.

[0068] In the present invention, it is preferred that:

[0069] The stator has an A-phase stator and a B-phase stator,

[0070] The voltage acquisition unit acquires the voltage generated in the stepping motor when a drive current is supplied to only one of the A-phase stator and the B-phase stator in response to the input of the pulse from the rotation control unit to the stepping motor.

[0071] In order to achieve the above object, another embodiment of the present invention relates to an electric valve control device that controls the electric valve.

[0072] The electric valve comprises: a valve body having a valve port; a stepping motor having a rotor and a stator; a valve core facing the valve port and moving toward the valve port when the rotor rotates in a first direction; and a stopper mechanism for limiting the rotation of the rotor in the first direction when the rotor is in a reference position, wherein:

[0073] a rotation control unit that inputs pulses to the stepping motor to rotate the rotor;

[0074] a current acquisition unit configured to acquire a current generated in the stator by the rotor rotating in the first direction;

[0075] a state determination unit that determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted based on a difference between the waveform of the current and a reference waveform of the current; and

[0076] a reference waveform setting unit that sets a reference waveform of the current,

[0077] The rotation control unit performs a second preparatory operation of inputting a second preparatory number of pulses to the stepping motor to rotate the rotor in a second direction. Following the second preparatory operation, the rotation control unit performs a first preparatory operation of inputting a first preparatory number of pulses less than the second preparatory number to the stepping motor to rotate the rotor in the first direction.

[0078] The reference waveform setting unit sets the waveform of the current acquired by the current acquisition unit in the first preparatory operation as a reference waveform of the current.

[0079] In order to achieve the above-mentioned object, a motor-driven valve device according to another aspect of the present invention includes: the motor-driven valve control device; and the motor-driven valve.

[0080] In order to achieve the above object, another aspect of the present invention relates to a method for controlling an electric valve, wherein the electric valve comprises:

[0081] A valve body having a valve port; a stepping motor having a rotor and a stator; a valve core opposite the valve port and moving toward the valve port when the rotor rotates in a first direction; and a stop mechanism for limiting rotation of the rotor in the first direction when the rotor is in a reference position, wherein the invention comprises:

[0082] a second preparation step of inputting a second preparation number of pulses into the stepping motor to rotate the rotor in a second direction;

[0083] a first preparation step, followed by the second preparation step, inputting a first preparation number of pulses less than the second preparation number into the stepping motor to rotate the rotor in the first direction;

[0084] A positioning step, subsequent to the first preparation step, inputting pulses to the stepping motor to rotate the rotor in the first direction;

[0085] a voltage obtaining step of obtaining a voltage generated on the stator by the rotation of the rotor in the first direction;

[0086] a reference waveform setting step of setting the voltage waveform obtained in the first preparation step as a reference waveform of the voltage; and

[0087] The state determining step determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted, based on a difference between the voltage waveform acquired in the positioning step and a reference voltage waveform.

[0088] In order to achieve the above object, another aspect of the present invention relates to a method for controlling an electric valve, wherein the electric valve comprises:

[0089] A valve body having a valve port; a stepping motor having a rotor and a stator; a valve core opposite to the valve port, wherein the valve core moves toward the valve port when the rotor rotates in a first direction; and a stop mechanism that restricts the rotor from rotating in the first direction when the rotor is in a reference position, wherein the stepping motor comprises:

[0090] a second preparation step of inputting a second preparation number of pulses into the stepping motor to rotate the rotor in a second direction;

[0091] a first preparation step, followed by the second preparation step, inputting a first preparation number of pulses less than the second preparation number into the stepping motor to rotate the rotor in the first direction;

[0092] A positioning step, subsequent to the first preparation step, inputting pulses to the stepping motor to rotate the rotor in the first direction;

[0093] a current acquiring step of acquiring a current generated in the stator by the rotation of the rotor in the first direction;

[0094] a reference waveform setting step of setting the waveform of the current acquired in the first preparation step as a reference waveform of the current; and

[0095] The state determining step determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted, based on a difference between the waveform of the current acquired in the positioning step and a reference waveform of the current.

[0096] Effects of the Invention

[0097] According to one embodiment of the present invention, the electric valve control device inputs a second preparation number of pulses to the stepping motor to rotate the rotor in the second direction (second preparation action). Following the second preparation action, the electric valve control device inputs a first preparation number of pulses to the stepping motor to rotate the rotor in the first direction (first preparation action). The first preparation number is less than the second preparation number. The electric valve control device obtains the voltage generated at the stator by the rotation of the rotor in the first direction. The electric valve control device sets the waveform of the voltage obtained in the first preparation action as a reference waveform of the voltage. The electric valve control device determines whether the electric valve is in the first rotation restriction state in which the rotation of the rotor in the first direction is restricted based on the difference between the waveform of the voltage and the reference waveform of the voltage.

[0098] According to another embodiment of the present invention, the electric valve control device inputs a second preparation number of pulses to the stepping motor to rotate the rotor in the second direction (second preparation action). Following the second preparation action, the electric valve control device inputs a first preparation number of pulses to the stepping motor to rotate the rotor in the first direction (first preparation action). The first preparation number is less than the second preparation number. The electric valve control device obtains the current generated in the stator by the rotation of the rotor in the first direction. The electric valve control device sets the waveform of the current obtained in the first preparation action as the reference waveform of the current. The electric valve control device determines whether the electric valve is in the first rotation restriction state in which the rotation of the rotor in the first direction is restricted based on the difference between the waveform of the current and the reference waveform of the current.

[0099] Thus, for a normally operating electric valve, when the electric valve control device determines that the electric valve is in the first rotation-restricted state, the rotor is located at the reference position. Therefore, when the electric valve is determined to be in the first rotation-restricted state, the electric valve control device stops the rotor from rotating in the first direction, thereby shortening the time required for initialization. Furthermore, this can suppress the generation of noise that occurs long after the rotor is positioned at the reference position.

[0100] Furthermore, the electric valve control device determines the state of the electric valve based on the difference between the voltage waveform and a reference voltage waveform. Therefore, compared to a configuration that determines the state of the electric valve based on the area or maximum amplitude of the voltage waveform, the electric valve state can be determined with higher accuracy.

[0101] Furthermore, the electric valve control device sets the voltage waveform acquired a short time after the electric valve starts operating as the voltage reference waveform. Therefore, the relatively stable voltage waveform acquired during actual use of the electric valve can be used as the voltage reference waveform, enabling the electric valve's state to be determined with greater accuracy.

[0102] Even in a configuration in which the electric valve control device uses a current waveform instead of a voltage waveform, the same operational effects as those of a configuration in which a voltage waveform is used are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0103] Figure 1 This is a block diagram of an air conditioner having an electric valve device.

[0104] Figure 2 yes Figure 1 A cross-sectional view of an electric valve device.

[0105] Figure 3 Yes Figure 2 FIG. 1 is a diagram of a valve shaft retainer included in an electric valve device.

[0106] Figure 4 yes Figure 2 A side view of a guide bushing included in the electric valve device.

[0107] Figure 5 Yes Figure 2 FIG. 1 is a diagram of a stopper component included in an electric valve device.

[0108] Figure 6 yes Figure 2 A top view of a valve shaft holder, a stop member, a rotor, and a stator included in an electric valve device.

[0109] Figure 7 It is an explanation Figure 2 Diagram of the computer, motor driver, and stepper motor included in the electric valve device.

[0110] Figure 8 This is a diagram schematically showing the positional relationship between the magnetic poles of the rotor and the pole teeth of the stator (when pulse P[1] is input).

[0111] Figure 9 This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[2] is input).

[0112] Figure 10 This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[3] is input).

[0113] Figure 11 This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[4] is input).

[0114] Figure 12 This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[5] is input).

[0115] Figure 13This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[6] is input).

[0116] Figure 14 This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[7] is input).

[0117] Figure 15 This is a diagram schematically showing the positional relationship between the rotor's magnetic poles and the stator's pole teeth (when pulse P[8] is input).

[0118] Figure 16 This is a diagram showing an example of a waveform of a voltage generated in the stator by the rotation of the rotor when the electric valve is in the first rotation-permitted state and is cooling.

[0119] Figure 17 This is a diagram showing an example of a waveform of a voltage generated in the stator by the rotation of the rotor after the electric valve is in the first rotation permission state and the temperature has increased.

[0120] Figure 18 This is a diagram showing an example of a waveform of a voltage generated in the stator by the rotation of the rotor after the electric valve is in the first rotation-permitted state and the temperature has sufficiently increased.

[0121] Figure 19 This is a diagram showing an example of a waveform of a voltage generated in a stator due to rotation of a rotor when the electric valve is in the first rotation restricted state.

[0122] Figure 20 This is a diagram showing an example of a data table showing a reference waveform of a voltage.

[0123] Figure 21 It is a diagram showing an example of a voltage waveform and a voltage reference waveform.

[0124] Figure 22 This is a flowchart showing an operation example 1 of the electric valve control device according to one embodiment of the present invention.

[0125] Figure 23 This is a flowchart showing operation example 1 (second preparatory operation).

[0126] Figure 24 This is a flowchart showing operation example 1 (first preparatory operation).

[0127] Figure 25 This is a flowchart showing an example of operation 1 (first preparatory operation, followed by Figure 24 ).

[0128] Figure 26 This is a flowchart showing operation example 1 (positioning operation).

[0129] Figure 27 This is a flowchart showing a second operation example of the electric valve control device according to one embodiment of the present invention.

[0130] Figure 28 This is a flowchart showing operation example 2 (first preparatory operation).

[0131] Figure 29 This is a flowchart showing the second example of operation (first preparatory operation, then Figure 28 ).

[0132] Figure 30 This is a flowchart showing the second example of operation (first preparatory operation, then Figure 29 ).

[0133] Explanation of symbols

[0134] 1…Electric Valve Device, 5…Electric Valve, 10…Valve Body, 11…Main Body, 11a…Mating Hole, 11b…Through Hole, 11d…Flat Surface, 13…Connecting Component, 14…Valve Chamber, 15…First Conduit, 16…Second Conduit, 17…Valve Port, 18…Valve Seat, 20…Casing, 30…Valve Element, 31…First Shaft, 32…Second Shaft, 33…Valve, 34…Step, 40…Drive Mechanism, 41…Rotor, 41a…Mating Hole, 42…Valve Shaft Retainer, 42a…Upper Wall, 42b…Shaft Hole, 42c…Internal Thread, 42s…Moveable Stopper, 43…Guide Bushing Sleeve, 43a…base, 43b…support, 43c…external thread, 43d…flat surface, 44…stopper, 44a…stopper body, 44c…internal thread, 44s…fixed stopper, 45…fixing member, 45a…fixing portion, 45b…flange, 46…washer, 47…valve closing spring, 48…return spring, 49…stopper mechanism, 60…stator, 61…A-phase stator, 61a…pole teeth, 61b…pole teeth, 61c…coil, 62…B-phase stator, 62a…pole teeth, 62b…pole teeth, 62c…coil, 66…stepping motor, 70…electric valve control device, 7 1…Substrate, 75…Non-volatile memory, 76…Communication device, 77…Motor driver, 80…Computer, 81…Rotation control unit, 82…Voltage acquisition unit, 83…State determination unit, 84…Reference waveform setting unit, 100…Air conditioner, 101…Compressor, 102…Condenser, 103…Evaporator, 105…Pipe, 110…Air conditioner control device, 120…Wired communication bus, A1…Terminal, A2…Terminal, B1…Terminal, B2…Terminal, L…Axis line, T…Period, t1…Time, t2…Time, p1…First period, p2…Second period, C…Reference waveform Shape table, C1…first reference waveform table, C2…second reference waveform table, G…similarity judgment value, H…difference judgment value, Ni…initialization quantity, Ns…stroke quantity, N2…second preparation quantity, N1…first preparation quantity, Nx…start mode number, P…pulse, Rc…valve closing position, Ro…valve opening position, Rx…reference position, Rz…fully open position, Sp1…first rotation permission state, Sr1…first rotation restriction state, sv…difference index value, sv1…first difference index value, sv2…second difference index value, V…voltage, VA…voltage, VB…voltage. DETAILED DESCRIPTION

[0135] Below, refer to Figures 1 to 30 , the electric valve device is explained.

[0136] Figure 1 This is a block diagram of an air conditioner having an electric valve device. Figure 2 yes Figure 1 A cross-sectional view of an electric valve device. Figure 3Yes Figure 2 FIG. 1 is a diagram of a valve shaft retainer included in an electric valve device. Figure 3 (A) is a three-dimensional diagram of the valve shaft retainer. Figure 3 (B) is a top view of the valve shaft retainer. Figure 4 yes Figure 2 A side view of a guide bushing included in the electric valve device.

[0137] Figure 5 Yes Figure 2 FIG. 1 is a diagram of a stopper component included in an electric valve device. Figure 5 (A) is a three-dimensional diagram of the stopper. Figure 5 (B) is a top view of the stopper component. Figure 6 yes Figure 2 A top view of the valve shaft holder, stopper, rotor and stator of the electric valve device. Figure 6 In FIG, the stator is schematically shown. In addition, Figure 6 , the magnetic poles of the rotor are schematically shown. Figure 7 It is an explanation Figure 2 Diagram of the computer, motor driver, and stepper motor included in the electric valve device. Figure 7 (A) schematically shows the connection between the computer, the motor driver, and the stepping motor included in the electric valve control device. Figure 7 (B) shows an example of the correspondence between the pulse and the drive current supplied by the motor driver to the stator.

[0138] Figures 8 to 15 This is a diagram schematically showing the positional relationship between the magnetic poles of the rotor and the pole teeth of the stator. Figures 8 to 15 Indicates the situation when pulses P[1] to P[8] are input to the stepper motor. Figures 8 to 15 In FIG, the stator is schematically shown. In addition, Figures 8 to 15 , the magnetic poles of the rotor are schematically shown.

[0139] Figures 16 to 19 This is a diagram showing an example of a waveform of a voltage generated in a stator due to the rotation of a rotor. Figure 16 This is a diagram showing an example of a voltage waveform when the electric valve is in the first rotation permission state and is cooling. Figure 17 This is a diagram showing an example of a voltage waveform when the electric valve is in the first rotation permission state and the temperature has increased. Figure 18 This is a diagram showing an example of a voltage waveform when the electric valve is in the first rotation permission state and the temperature has been sufficiently increased. Figure 19 1 is a diagram showing an example of a voltage waveform when the electric valve is in the first rotation restricted state. Figure 20 This is a diagram showing an example of a data table showing a reference waveform of a voltage. Figure 21It is a diagram showing an example of a voltage waveform and a voltage reference waveform.

[0140] Figures 22 to 26 This is a flowchart showing an operation example 1 of the electric valve control device according to one embodiment of the present invention. Figure 22 This section shows the main flow of Action Example 1. Figure 23 This section shows the second preparatory operation of Operation Example 1. Figure 24 、 Figure 25 The first preparatory operation of operation example 1 is shown. Figure 26 This shows the positioning action of action example 1.

[0141] Figures 27 to 30 This is a flowchart showing a second operation example of the electric valve control device according to one embodiment of the present invention. Figure 27 This section shows the main flow of Action Example 2. Figures 28 to 30 This shows the first preparatory operation of operation example 2.

[0142] The electric valve device 1 according to the present embodiment is used as a flow control valve for controlling the flow rate of a refrigerant as a fluid in, for example, a refrigeration cycle system of an air conditioner.

[0143] Figure 1 The figure shows an example of an air conditioner 100 installed in a vehicle. The air conditioner 100 includes a compressor 101, a condenser 102, an electric valve device 1 (electric valve 5), and an evaporator 103, which are sequentially connected via a pipe 105. The electric valve device 1 is an expansion valve. The air conditioner 100 includes an air conditioner control device 110. The air conditioner control device 110 is communicatively connected to the electric valve device 1. The air conditioner control device 110 uses the electric valve device 1 to control the flow rate of the refrigerant flowing through the pipe 105.

[0144] like Figure 2 As shown, the electric valve device 1 includes a electric valve 5 and an electric valve control device 70 .

[0145] The electric valve 5 includes a valve body 10 , a housing 20 , a valve element 30 , a drive mechanism 40 , and a stator 60 .

[0146] The valve body 10 includes a main body part 11 and a connecting part 13. The main body part 11 has a cylindrical shape. The main body part 11 includes: a valve chamber 14, a valve port 17, and a valve seat 18. A first conduit 15 and a second conduit 16 are connected to the main body part 11. The first conduit 15 extends in a direction perpendicular to the axis L ( Figure 2 The second conduit 16 is arranged along the axis L direction ( Figure 2The main body 11 has a circular fitting hole 11a. The fitting hole 11a is arranged on the upper end surface of the main body 11. The inner circumference of the fitting hole 11a has a Figure 2 The bottom surface of the fitting hole 11a is provided with a through hole 11b that communicates with the valve chamber 14. The connecting member 13 has a circular plate shape. The inner periphery of the connecting member 13 is joined to the upper end of the main body 11. The main body 11 and the connecting member 13 are made of metal such as aluminum alloy, stainless steel, or brass.

[0147] The housing 20 is made of metal such as stainless steel. The housing 20 has a cylindrical shape. The lower end of the housing 20 is open and the upper end is closed. The lower end of the housing 20 is joined to the outer periphery of the connecting member 13.

[0148] The valve core 30 includes a first shaft portion 31, a second shaft portion 32, and a valve portion 33. The first shaft portion 31 is cylindrical. The second shaft portion 32 is also cylindrical. The diameter of the second shaft portion 32 is smaller than that of the first shaft portion 31. The second shaft portion 32 is coaxially connected to the upper end of the first shaft portion 31. The valve core 30 includes a step portion 34, which is an upward-facing annular flat surface. The step portion 34 is located at the connection between the first and second shaft portions 31 and 32. The valve portion 33 has a generally conical shape, with the diameter decreasing from top to bottom. The valve portion 33 is coaxially connected to the lower end of the first shaft portion 31. The valve portion 33 is located at the valve port 17. A variable throttle portion is formed between the valve portion 33 and the valve port 17. The valve portion 33 faces the valve port 17 and the valve seat 18. When the valve portion 33 contacts the valve seat 18, the valve port 17 is closed. When the valve portion 33 leaves the valve seat 18 , the valve port 17 opens.

[0149] The drive mechanism 40 moves the valve element 30 in the vertical direction (direction of the axis L). The movement of the valve element 30 opens and closes the valve port 17. The drive mechanism 40 includes a rotor 41, a valve shaft holder 42, a guide bushing 43, a stopper 44, and a stator 45.

[0150] The rotor 41 has a cylindrical shape. The outer diameter of the rotor 41 is slightly smaller than the inner diameter of the housing 20. The rotor 41 is arranged on the inner side of the housing 20. The rotor 41 is rotatable relative to the valve body 10. The rotor 41 has a plurality of north poles and a plurality of south poles. The plurality of north poles and the plurality of south poles are arranged on the outer peripheral surface of the rotor 41. The plurality of north poles and the plurality of south poles extend in the vertical direction. The plurality of north poles and the plurality of south poles are alternately arranged at equal angular intervals in the circumferential direction. For example, the rotor 41 has 12 north poles and 12 south poles. The angle between adjacent north poles and south poles is 15 degrees.

[0151] Figure 3Figure 4 shows the valve shaft holder 42. The valve shaft holder 42 has a cylindrical shape. The lower end of the valve shaft holder 42 is open. An upper wall portion 42a is provided at the upper end of the valve shaft holder 42. The upper wall portion 42a has a shaft hole 42b. The valve shaft holder 42 engages with the fitting hole 41a of the rotor 41. The valve shaft holder 42 rotates together with the rotor 41. A movable stopper 42s is provided at the lower end of the outer circumference of the valve shaft holder 42. The movable stopper 42s is a protrusion that protrudes radially outward. The second shaft portion 32 of the valve core 30 is arranged in the shaft hole 42b so as to be movable along the axis L. A washer 46 is provided on the lower surface of the upper wall portion 42a of the valve shaft holder 42. A valve closing spring 47 is provided between the washer 46 and the step portion 34 of the valve core 30. The valve closing spring 47 is a coil spring that presses the valve core 30 toward the valve seat 18. An internal thread 42 c is provided on the inner peripheral surface of the valve shaft holder 42 . The movable stopper 42 s is fixed to the rotor 41 .

[0152] Figure 4 The guide bushing 43 is shown. The guide bushing 43 has a base 43a and a support portion 43b. The base 43a has a cylindrical shape. The outer circumferential surface of the base 43a has a flat surface 43d. The base 43a is pressed into the fitting hole 11a of the main body 11, so that the flat surface 43d contacts the flat surface 11d of the fitting hole 11a. This aligns the center axis of the main body 11 and the center axis of the guide bushing 43 on the axis L, and the guide bushing 43 is correctly positioned relative to the main body 11 about the axis L. The support portion 43b has a cylindrical shape. The outer diameter of the support portion 43b is smaller than the outer diameter of the base 43a. The inner diameter of the support portion 43b is the same as the inner diameter of the base 43a. The support portion 43b is coaxially connected to the upper end of the base 43a. An external thread 43c is provided on the outer circumferential surface of the support portion 43b. The external thread 43c screws into the internal thread 42c of the valve shaft retainer 42. The first shaft portion 31 of the valve element 30 is arranged inside the guide bushing 43. The guide bushing 43 supports the valve element 30 so as to be movable in the axis L direction.

[0153] Figure 5 The stop member 44 is shown. The stop member 44 includes a stop member body 44a. The stop member body 44a has a cylindrical shape. An internal thread 44c is provided on the inner circumference of the stop member body 44a. A fixed stop member 44s is disposed on the outer circumference of the stop member body 44a. The fixed stop member 44s is a protrusion that protrudes radially outward. The internal thread 44c is threadedly engaged with the external thread 43c until the stop member body 44a abuts the base 43a of the guide bushing 43. This secures the stop member 44 to the guide bushing 43. The fixed stop member 44s is fixed to the valve body 10.

[0154] The fixing member 45 includes a fixing portion 45a and a flange portion 45b. The fixing portion 45a has a stepped cylindrical shape. The second shaft portion 32 of the valve core 30 is disposed inside the fixing portion 45a. The fixing portion 45a is engaged with the second shaft portion 32. The flange portion 45b is connected to the lower end of the fixing portion 45a. A return spring 48 is disposed outside the fixing member 45. The return spring 48 is a coil spring.

[0155] The electric valve 5 includes a drive mechanism 40 for not reducing the speed of rotation of the rotor 41. The electric valve 5 may include a drive mechanism including a speed reduction mechanism for reducing the speed of rotation of the rotor 41 instead of the drive mechanism 40.

[0156] The stator 60 has a cylindrical shape and includes an A-phase stator 61 and a B-phase stator 62 .

[0157] The A-phase stator 61 has a plurality of salient pole teeth 61a and 61b on its inner circumference. The top of the pole tooth 61a faces downward, and the top of the pole tooth 61b faces upward. The pole teeth 61a and the pole teeth 61b are alternately arranged at equal angular intervals in the circumferential direction. For example, the A-phase stator 61 has 12 pole teeth 61a and 12 pole teeth 61b. The angle between adjacent pole teeth 61a and pole teeth 61b is 15 degrees. When the coil 61c of the A-phase stator 61 is energized, the pole teeth 61a and the pole teeth 61b become magnetic poles of different polarities.

[0158] The B-phase stator 62 has multiple salient-pole pole teeth 62a and 62b on its inner circumference. The top of the pole teeth 62a faces downward, and the top of the pole teeth 62b faces upward. The pole teeth 62a and the pole teeth 62b are alternately arranged at equal angular intervals in the circumferential direction. For example, the B-phase stator 62 has 12 pole teeth 62a and 12 pole teeth 62b. The angle between adjacent pole teeth 62a and pole teeth 62b is 15 degrees. When the coil 62c of the B-phase stator 62 is energized, the pole teeth 62a and the pole teeth 62b become magnetic poles of different polarities.

[0159] The A-phase stator 61 and the B-phase stator 62 are coaxially arranged. The A-phase stator 61 is in contact with the B-phase stator 62. When viewed from the axis L, the angle between the adjacent pole teeth 61a of the A-phase stator 61 and the pole teeth 62a of the B-phase stator 62 is 7.5 degrees. That is, the B-phase stator 62 is located at a position rotated 7.5 degrees around the axis L relative to the A-phase stator 61 from the position where the pole teeth 61a and the pole teeth 62a are arranged in the axis L direction. Figure 7 As shown in FIG. 1A , terminals A1 and A2 of the coil 61 c of the A-phase stator 61 and terminals B1 and B2 of the coil 62 c of the B-phase stator 62 are connected to the electric valve control device 70 (motor driver 77 ).

[0160] The housing 20 is arranged inside the stator 60. The rotor 41 is arranged inside the housing 20. The stator 60 and the rotor 41 constitute a stepping motor 66.

[0161] The rotor 41 is rotated by inputting pulses P (P[1] to P[8]) to the stepping motor 66. Specifically, the rotor 41 is rotated by supplying a drive current corresponding to the pulses P to the stator 60 of the stepping motor 66. In this specification, "inputting pulses P to the stepping motor 66" and "supplying a drive current corresponding to the pulses P to the stator 60 of the stepping motor 66" have the same meaning.

[0162] Input the following signals to the stepping motor 66: Figure 7 Pulses P[1] to P[8] are shown in (B). The combination of the drive current supplied to the A-phase stator 61 and the drive current supplied to the B-phase stator 62 is different for each pulse P. The number of combinations is 8, which is called the number of modes of pulse P. "Mode" is also called "switching mode". The numbers (1 to 8) of pulses P[1] to P[8] are used to identify the mode numbers of pulses P[1] to P[8]. For example, the period of pulse P is 8 ms, and a period T including pulses P[1] to P[8] is 64 ms.

[0163] Figures 8 to 15 An example of the positional relationship between the rotor 41 and the stator 60 when pulses P[1] to P[8] are input is shown. Figures 8 to 15 In the figure, in order to easily understand the positional relationship between the rotor 41 and the stator 60 (A-phase stator 61 and B-phase stator 62), black dots are added to the reference pole teeth 61a and the reference magnetic pole (S pole) of the rotor 41.

[0164] When the rotor 41 is moved in the first direction (in Figures 8 to 15When the rotor 41 rotates in the first direction (in the clockwise direction), pulses P are cyclically input to the stepping motor 66 in ascending order (in the order of pulses P[1] to P[8]). When the rotor 41 rotates in the first direction, the rotor 41 and the valve shaft holder 42 move downward due to the thread feed action of the internal thread 42c of the valve shaft holder 42 and the external thread 43c of the guide bushing 43. The rotor 41 (valve shaft holder 42) presses the valve core 30 downward via the valve closing spring 47. The valve core 30 moves downward so that the valve portion 33 contacts the valve seat 18. The position of the rotor 41 at this time is the valve closing position Rc. When the rotor 41 is further rotated in the first direction from this state, the valve closing spring 47 is compressed, and the rotor 41 moves further downward. The valve core 30 does not move downward. In addition, when the movable stopper 42s of the valve shaft holder 42 contacts the fixed stopper 44s of the stop member 44, the rotation of the rotor 41 in the first direction is restricted. The position of the rotor 41 at this time is the reference position Rx. The movable stopper 42s and the fixed stopper 44s constitute a stopper mechanism 49 that restricts the rotation of the rotor 41 in the first direction.

[0165] When the rotor 41 is moved in a second direction opposite to the first direction (in Figures 8 to 15 When the rotor 41 rotates in the second direction (in the counterclockwise direction), pulses P are cyclically input to the stepping motor 66 in descending order (in the order of pulses P[8] to P[1]). When the rotor 41 rotates in the second direction, the rotor 41 and the valve shaft holder 42 move upward due to the thread feed action of the internal thread 42c of the valve shaft holder 42 and the external thread 43c of the guide bushing 43. The rotor 41 (valve shaft holder 42) presses the fixing member 45 upward. The valve core 30 moves upward together with the fixing member 45, and the valve core 30 leaves the valve seat 18. The position of the rotor 41 when the flow rate of the fluid at the valve port 17 (the opening of the valve port 17) in a specified flow measurement environment is a specified set value is referred to as the valve opening position Ro. The set value is appropriately set according to the structure, application, etc. of the electric valve device 1. When the rotor 41 rotates in the second direction and reaches the fully open position Rz, the valve core 30 is farthest away from the valve port 17, and the valve port 17 becomes the maximum opening.

[0166] The number of pulses P required to rotate the rotor 41 from the fully open position Rz to the reference position Rx is referred to as the stroke number Ns. Specifically, when pulses P for the stroke number Ns are input to the stepping motor 66 of the electric valve 5 with the rotor 41 in the fully open position Rz, the rotor 41 is positioned at the reference position Rx. For example, the stroke number Ns is 500. The number of pulses P required to rotate the rotor 41 from the reference position Rx to the fully open position Rz is also referred to as the stroke number Ns.

[0167] The initialization number Ni is set based on the stroke number Ns. The initialization number Ni is the number of pulses P sufficient to rotate the rotor 41 from the fully open position Rz to the reference position Rx. In other words, regardless of the position of the rotor 41, when the initialization number Ni of pulses P is input to the stepping motor 66, the rotor 41 can be positioned at the reference position Rx. The initialization number Ni is, for example, 1.05 to 1.3 times the stroke number Ns.

[0168] The second preparation quantity N2 and the first preparation quantity N1 are set based on the stroke number Ns. The second preparation quantity N2 and the first preparation quantity N1 are used for the initialization operation, which is the operation of positioning the rotor 41 to the reference position Rx. The second preparation quantity N2 is, for example, 0.05 to 0.3 times the stroke number Ns. The first preparation quantity N1 and the second preparation quantity N2 are the same. The first preparation quantity N1 can be smaller than the second preparation quantity N2. Preferably, the first preparation quantity N1 is 0.8 to 1 times the second preparation quantity N2.

[0169] In the electric valve 5 , the center axes of the valve port 17 , valve seat 18 , housing 20 , valve element 30 , rotor 41 , valve shaft holder 42 , guide bushing 43 , and stator 60 (A-phase stator 61 , B-phase stator 62 ) coincide with the axis L.

[0170] The electric valve control device 70 includes a substrate 71 on which a plurality of electronic components (not shown) are mounted. Figure 1 As shown, the electric valve control device 70 includes a nonvolatile memory 75 , a communication device 76 , a motor driver 77 , and a computer 80 . The electric valve control device 70 controls the electric valve 5 based on a command from the air conditioning control device 110 .

[0171] The nonvolatile memory 75 stores data that needs to be saved even when the power is turned off. The nonvolatile memory 75 is, for example, an EEPROM or a flash memory.

[0172] Communication device 76 is communicatively connected to air conditioning control device 110 via wired communication bus 120. Air conditioner 100 employs a communication method such as a Local Interconnect Network (LIN) or a Controller Area Network (CAN). Communication device 76 may also be wirelessly connected to air conditioning control device 110.

[0173] The motor driver 77 supplies a driving current to the stepping motor 66 based on the pulse P input from the computer 80. Figure 7 As shown in FIG. 1A , the motor driver 77 is connected to the terminals A1 and A2 of the coil 61 c of the A-phase stator 61 and the terminals B1 and B2 of the coil 62 c of the B-phase stator 62 .

[0174] Figure 7 (B) shows an example of the correspondence between the pulse P and the drive current supplied by the motor driver 77. Figure 7 In (B), (+) indicates that a driving current is supplied from terminal A1 to terminal A2 or a driving current is supplied from terminal B1 to terminal B2, (-) indicates that a driving current is supplied from terminal A2 to terminal A1 or a driving current is supplied from terminal B2 to terminal B1, and (0) indicates that no driving current is supplied.

[0175] When a pulse P[1] is input from the computer 80, the motor driver 77 supplies a drive current (+) from the terminal A1 to the terminal A2 to the coil 61c, and does not supply a drive current (0) to the coil 62c.

[0176] When a pulse P[2] is input from the computer 80, the motor driver 77 supplies a drive current (+) from the terminal A1 to the terminal A2 to the coil 61c, and supplies a drive current (+) from the terminal B1 to the terminal B2 to the coil 62c.

[0177] When the pulse P[3] is input from the computer 80, the motor driver 77 does not supply a driving current (0) to the coil 61c, and supplies a driving current (+) from the terminal B1 to the terminal B2 to the coil 62c.

[0178] When a pulse P[4] is input from the computer 80, the motor driver 77 supplies a drive current (-) from the terminal A2 to the terminal A1 to the coil 61c, and supplies a drive current (+) from the terminal B1 to the terminal B2 to the coil 62c.

[0179] When the pulse P[5] is input from the computer 80, the motor driver 77 supplies a drive current (-) from the terminal A2 to the terminal A1 to the coil 61c, and does not supply a drive current (0) to the coil 62c.

[0180] When a pulse P[6] is input from the computer 80, the motor driver 77 supplies a drive current (-) from the terminal A2 to the terminal A1 to the coil 61c, and supplies a drive current (-) from the terminal B2 to the terminal B1 to the coil 62c.

[0181] When the pulse P[7] is input from the computer 80, the motor driver 77 does not supply a driving current (0) to the coil 61c, and supplies a driving current (-) from the terminal B2 to the terminal B1 to the coil 62c.

[0182] When a pulse P[8] is input from the computer 80, the motor driver 77 supplies a drive current (+) from the terminal A1 to the terminal A2 to the coil 61c, and supplies a drive current (-) from the terminal B2 to the terminal B1 to the coil 62c.

[0183] Computer 80 is a microcomputer for embedded devices, integrating a CPU, ROM, RAM, input / output interfaces, and an A / D converter into a single package. Computer 80 may also include nonvolatile memory 75, a communication device 76, and a motor driver 77. Computer 80 functions as a rotation control unit 81, a voltage acquisition unit 82, a state determination unit 83, and a reference waveform setting unit 84 by having the CPU execute programs stored in the ROM. Computer 80 is a processing device.

[0184] The rotation control unit 81 inputs pulses P to the stepping motor 66 to rotate the rotor 41 in the first direction or the second direction. Specifically, the rotation control unit 81 inputs pulses P[1] to P[8] to the motor driver 77 based on a command received from the air conditioning control device 110. The motor driver 77 supplies drive current to the coil 61c of the A-phase stator 61 and the coil 62c of the B-phase stator 62 in accordance with the input pulses P[1] to P[8].

[0185] The voltage acquisition unit 82 acquires a voltage generated in the stator 60 by the rotation of the rotor 41 , that is, a voltage obtained by the stator 60 through electromagnetic induction.

[0186] Specifically, when the rotation control unit 81 supplies drive current only to the coil 61c of the A-phase stator 61 in accordance with pulses P[1] and P[5], the voltage acquisition unit 82 time-series acquires the voltage VB generated between the terminals B1 and B2 of the coil 62c of the B-phase stator 62. When the rotation control unit 81 supplies drive current only to the coil 62c of the B-phase stator 62 in accordance with pulses P[3] and P[7], the voltage acquisition unit 82 time-series acquires the voltage VA generated between the terminals A1 and A2 of the coil 61c of the A-phase stator 61. When the rotation control unit 81 supplies drive current to the coils 61c and 62c in accordance with pulses P[2], P[4], P[6], and P[8], the voltage acquisition unit 82 does not acquire the voltages VA and VB. In the following description, "voltage V" is simply used to refer to "voltage VA and voltage VB."

[0187] Alternatively, the voltage acquisition unit 82 may acquire the voltage V in a time series when the rotation control unit 81 supplies the drive current to the coils 61c and 62c according to the pulses P[1] to P[8]. In this configuration, the voltage acquisition unit 82 separates the voltage component related to electromagnetic induction from the voltage generated between terminals A1 and A2 and obtains this voltage component as the voltage VA. The voltage acquisition unit 82 separates the voltage component related to electromagnetic induction from the voltage generated between terminals B1 and B2 and obtains this voltage component as the voltage VB.

[0188] The voltage acquisition unit 82 acquires the voltage V in a time series at a predetermined sampling period from the beginning to the end of the pulse P. For example, the period from the beginning to the end of the pulse P is 8 ms, and the sampling period is 200 μs. For example, the voltage acquisition unit 82 acquires the voltage V 40 times for each input pulse P[k] (k = 1, 3, 5, 7).

[0189] The voltage V obtained in time series is the waveform of the voltage V. In this specification, a "waveform" is a change in a fixed point physical quantity (voltage) over time. When visualizing the "waveform", it is represented in a coordinate plane with the physical quantity as the vertical axis and time as the horizontal axis. In addition, invisible contents such as data tables stored in the RAM of the computer 80 and the non-volatile memory 75 that associate physical quantity data with time data are also included in the "waveform". In addition, the "area of ​​the waveform" refers to the area of ​​the area surrounded by the waveform and the horizontal axis when the waveform is represented in a coordinate plane with the physical quantity as the vertical axis and time as the horizontal axis corresponding to the physical quantity 0.

[0190] During the initialization operation, the state determination unit 83 determines the state of the electric valve 5 based on the waveform of the voltage V acquired by the voltage acquisition unit 82. The electric valve 5 has a first rotation-permitted state Sp1 and a first rotation-restricted state Sr1. The first rotation-permitted state Sp1 allows the rotor 41 to rotate in the first direction before reaching the reference position Rx. The first rotation-restricted state Sr1 restricts the rotor 41 from rotating in the first direction after reaching the reference position Rx and the movable stopper 42s abuts the fixed stopper 44s.

[0191] Figures 16 to 19 An example of the waveform of the voltage VB when the rotor 41 is rotated in the first direction (that is, when the electric valve 5 is actuated) is shown. Figure 16 An example of the waveform of the voltage VB immediately after the electric valve 5 in the first rotation permission state Sp1 starts operating is shown, that is, an example of the waveform of the voltage VB when the electric valve 5 is cooled. Figure 17 An example of the waveform of the voltage VB when the electric valve 5 is in the first rotation permission state Sp1 is in operation, that is, an example of the waveform of the voltage VB after the temperature of the electric valve 5 is increased is shown. Figure 18 An example of the waveform of the voltage VB when the operation of the electric valve 5 in the first rotation permission state Sp1 is further advanced, that is, an example of the waveform of the voltage VB after the temperature of the electric valve 5 is sufficiently increased, is shown. Figure 19 FIG. 1 shows an example of a waveform of the voltage VB of the electric valve in the first rotation restricted state Sr1. Figures 16 to 19 , voltage is the vertical axis and time is the horizontal axis.

[0192] The waveform of the voltage VB when the electric valve 5 is cooling ( Figure 16) and the waveform of the voltage VB after the electric valve 5 is heated ( Figure 17 、 Figure 18 Until the electric valve 5 is fully heated, the waveform of the voltage VB gradually changes ( Figure 16 、 Figure 17 ), if the electric valve 5 is sufficiently heated, the waveform of the voltage VB becomes stable ( Figure 18 This is presumably because when the electric valve 5 is actuated, the stator 60 generates heat, thereby increasing the temperature of the refrigerant in the housing 20 and reducing the viscosity of the refrigeration oil contained in the refrigerant.

[0193] In addition, the waveform of the voltage VB when the electric valve 5 is in the first rotation permission state Sp1 ( Figures 16 to 18 ) and the waveform of the voltage VB when the electric valve 5 is in the first rotation restricted state Sr1 ( Figure 19 Therefore, by setting the waveform of the voltage V after the electric valve 5 is heated (preferably sufficiently heated) as the reference waveform of the voltage V, and comparing the waveform of the voltage V obtained after the reference waveform is set with the reference waveform of the voltage V, it is possible to determine whether the electric valve 5 is in the first rotation-permitted state Sp1 or the first rotation-restricted state Sr1.

[0194] The state determination unit 83 compares the waveform of the voltage V with a reference waveform of the voltage V to determine the state of the electric valve 5 .

[0195] Furthermore, the state determination unit 83 compares the waveform of the voltage V with a reference waveform of the voltage V to determine whether the waveform of the voltage V is similar to the reference waveform of the voltage V. When the waveform of the voltage V is identical to the reference waveform of the voltage V, the state determination unit 83 also determines that "the waveform of the voltage V is similar to the reference waveform of the voltage V."

[0196] Reference waveform setting unit 84 sets a reference waveform for voltage V. The reference waveform for voltage VA is set based on voltage VA acquired by voltage acquisition unit 82. The reference waveform for voltage VB is set based on voltage VB acquired by voltage acquisition unit 82. Reference waveform setting unit 84 stores the reference waveforms for voltage VA and voltage VB in nonvolatile memory 75. Alternatively, reference waveform setting unit 84 may store the reference waveforms for voltage VA and voltage VB in the RAM of computer 80.

[0197] A reference waveform for voltage VA is set for each of pulses P[3] and P[7]. The reference waveform for voltage VA is set based on the waveform of voltage VA obtained when a drive current is supplied only to coil 62c of phase B stator 62 in response to pulses P[3] and P[7] input to stepper motor 66 when rotating rotor 41 in the first direction.

[0198] A reference waveform for voltage VB is set for each of pulses P[1] and P[5]. The reference waveform for voltage VB is set based on the waveform of voltage VB obtained when a drive current is supplied only to coil 61c of phase A stator 61 based on pulses P[1] and P[5] input to stepper motor 66 when rotating rotor 41 in the first direction.

[0199] The pulses P[1], P[3], P[5], and P[7] input to the stepping motor 66 when rotating the rotor 41 in the first direction are first direction pulses.

[0200] In the electric valve device 1, the reference waveform of the voltage V is set for a part of the pulses P (P[1], P[3], P[5], P[7]), and is not set for the remaining pulses P (P[2], P[4], P[6], P[8]).

[0201] The reference waveform of the voltage V is stored in the nonvolatile memory 75 as a data table.

[0202] The nonvolatile memory 75 stores reference waveform tables C[3] and C[7], which are reference waveforms for the voltage VA set for pulses P[3] and P[7]. The nonvolatile memory 75 stores reference waveform tables C[1] and C[5], which are reference waveforms for the voltage VB set for pulses P[1] and P[5].

[0203] Figure 20 An example of a reference waveform table C[1] is shown. In the data table, time t at a predetermined time interval from the beginning of the pulse P (time 0) and the reference voltage rv at that time t are associated. The interval of time t is the same as the sampling period (200μs) of the voltage acquisition unit 82. One data table has 40 sets of time t and reference voltage rv. Figure 20 In the example, the unit of time t is μs. The unit of reference voltage rv is mV. The unit of time t and the unit of reference voltage rv may be independent units such as units corresponding to the sampling cycle and resolution of the A / D converter included in the electric valve control device 70.

[0204] The state determination unit 83 calculates a value (difference index value sv) indicating the degree of difference between the waveform of the voltage V acquired by the voltage acquisition unit 82 and the reference waveform of the voltage V. The larger the difference index value sv, the greater the degree of difference between the waveform of the voltage V and the reference waveform of the voltage V. When the difference index value sv is greater than or equal to a predetermined difference determination value H, it is determined that the waveform of the voltage V is different from the reference waveform of the voltage V. The difference index value sv is also a value (similarity index value) indicating the degree of similarity between the waveform of the voltage V and the reference waveform of the voltage V. The smaller the difference index value sv, the greater the degree of similarity between the waveform of the voltage V and the reference waveform of the voltage V. When the difference index value sv is less than or equal to a predetermined similarity determination value G, it is determined that the waveform of the voltage V is similar to the reference waveform of the voltage V.

[0205] When voltage acquisition unit 82 acquires voltage v (voltage V) at acquisition time tv in response to input of pulse P[k] (k=1, 3, 5, 7), state determination unit 83 reads reference voltage rv associated with time t corresponding to acquisition time tv from a data table of reference waveforms corresponding to pulse P[k] (reference waveform table C[k]). State determination unit 83 calculates the value (difference dv) obtained by subtracting reference voltage rv from voltage v acquired by voltage acquisition unit 82. State determination unit 83 calculates the value (intermediate value dv2) obtained by squaring difference dv. State determination unit 83 calculates the difference index sv[k] by summing the multiple intermediate values ​​dv2 calculated in response to input of pulse P[k].

[0206] The state determination unit 83 calculates the difference index value sv[k] using the voltage v acquired by the voltage acquisition unit 82 during a portion of the period from the beginning to the end of the pulse P[k]. Specifically, the period from the beginning of the pulse P[k] to time t1 is defined as a first period p1, and the period from time t1 to time t2 is defined as a second period p2. The state determination unit 83 calculates the difference index value sv[k] using the voltage v during the second period p2. Time t1 is after the beginning of the pulse P[k]. Time t2 is after time t1 and before the end of the pulse P[k]. Time t2 may also be at the end of the pulse P[k]. Figure 21 An example of the waveform of the voltage VB acquired in response to the input of the pulse P[1] (solid line: "acquired waveform") and the reference waveform of the voltage VB (dashed line) are shown. Figure 21 The length of the vertical line connecting the waveform of voltage VB and the reference waveform of voltage VB in the second period p2 corresponds to the difference dv used to calculate the difference index value sv[1]. State determination unit 83 does not use voltage v in the first period p1 to calculate the difference index value sv[k].

[0207] The voltage v may include a voltage component related to the back electromotive force caused by the inductance of the coil of the stator 60 (the former voltage component) and a voltage component related to the electromagnetic induction caused by the rotation of the rotor 41 (the latter voltage component). At a moment slightly after the initial stage of the pulse P[k], the former voltage component is greater than the latter voltage component, and the former voltage component decreases over time. Therefore, the state determination unit 83 uses the voltage v obtained by the voltage acquisition unit 82 after a certain period of time has passed since the initial stage of the pulse P[k] to calculate the difference index value sv[k]. Specifically, the state determination unit 83 uses the voltage v obtained by the voltage acquisition unit 82 after the former voltage component becomes smaller than the latter voltage component to calculate the difference index value sv[k]. As a result, the proportion of the latter voltage component in the voltage v becomes relatively larger, and the state determination unit 83 can determine the state of the electric valve 5 with higher accuracy.

[0208] The length of the first period p1 is 5 to 50% of the period from the beginning to the end of the pulse P[k], preferably 20 to 30%. The length of the second period p2 is 50 to 95% of the period from the beginning to the end of the pulse P[k], preferably 70 to 80%. In the voltage v acquired by the voltage acquisition unit 82 during the second period p2, the voltage component related to the back electromotive force caused by the inductance of the coil of the stator 60 is smaller than the voltage component related to the electromagnetic induction caused by the rotation of the rotor 41. In addition, the state determination unit 83 can also use the voltage v acquired by the voltage acquisition unit 82 during the period from the beginning to the end of the pulse P[k] (the entire period) to calculate the difference index value sv[k]. In this structure, the beginning of the pulse P[k] is time t1, and the end of the pulse P[k] is time t2.

[0209] When the voltage v acquired at the acquisition time tv during the period from time t1 to time t2 is taken as v[tv], and the reference voltage rv associated with the time t corresponding to the acquisition time tv in the data table of the reference waveform is taken as rv[tv], the difference index value sv is expressed by the following mathematical formula (1).

[0210] [Mathematical formula 1]

[0211]

[0212] The state determination unit 83 determines the state of the electric valve 5 based on the difference index value sv[k]. Specifically, the state determination unit 83 compares the difference index value sv[k] with a specified difference determination value H. The state determination unit 83 determines whether the electric valve 5 is in the first rotation permission state Sp1 or the first rotation restriction state Sr1 based on the comparison result of the difference index value sv[k] and the difference determination value H. In addition, when the pulses P[2], P[4], P[6] and P[8] that rotate the rotor 41 in the first direction are input to the stepping motor 66, the state determination unit 83 determines that the electric valve 5 is in the first rotation permission state Sp1. The electric valve control device 70 may also have a difference determination value H[k] corresponding to the difference index value sv[k]. The difference determination values ​​H[k] may be the same value or different values ​​from each other.

[0213] The state determination unit 83 determines whether the waveform of the voltage V used to calculate the difference index value sv[k] is similar to a reference waveform of the voltage V. Specifically, the state determination unit 83 compares the difference index value sv[k] with a predetermined similarity determination value G. Based on the comparison result between the difference index value sv[k] and the similarity determination value G, the state determination unit 83 determines whether the waveform of the voltage V is similar to the reference waveform of the voltage V. The electric valve control device 70 may also have a similarity determination value G[k] corresponding to the difference index value sv[k]. The similarity determination values ​​G[k] may be the same value or different values.

[0214] Next, refer to Figures 22 to 26 Next, an example of the initialization operation of the electric valve control device 70 (operation example 1) will be described.

[0215] When the electric valve control device 70 (specifically, the computer 80) receives an initialization command from the air conditioning control device 110 (S100), it invalidates the reference waveform of the voltage V stored in the non-volatile memory 75 and then performs an initialization operation. The initialization operation includes a second preparatory operation (S200), a first preparatory operation (S400), and a positioning operation (S600). The second preparatory operation, the first preparatory operation, and the positioning operation correspond to the second preparatory step, the first preparatory step, and the positioning step.

[0216] (Second preparatory action)

[0217] During the second preparatory operation, the electric valve control device 70 begins inputting pulses P to the stepping motor 66 in descending order (YES in S210 and S220), thereby rotating the rotor 41 in the second direction. When the number of pulses P inputted to the stepping motor 66 during the second preparatory operation reaches the second preparatory number N2 (NO in S220), the electric valve control device 70 stops inputting pulses P to the stepping motor 66 (S230). The electric valve control device 70 then terminates the second preparatory operation and begins the first preparatory operation.

[0218] (First preparatory action)

[0219] When the first preparatory operation begins, the reference waveform of voltage V has not yet been set. "Not set" includes: the reference waveform of voltage V has never been set; the reference waveform of voltage V has been set but has never been used and has been overwritten by a newly set reference waveform of voltage V; and the reference waveform of voltage V has been set but has been recognized as invalid.

[0220] During the first preparatory operation, the electric valve control device 70 begins inputting pulses P to the stepping motor 66 in ascending order (YES in S410 and S420), thereby rotating the rotor 41 in the first direction. When the number of pulses P input to the stepping motor 66 reaches K during the first preparatory operation (NO in S420), the electric valve control device 70 acquires the waveform of the voltage V (S430) and sets a reference waveform for the voltage V (S440). Acquisition of the voltage V waveform begins with the Kth input pulse P during the first preparatory operation. K is a natural number greater than or equal to 1 and less than or equal to the first preparatory number N1. In the electric valve control device 70, K=1. K is preferably less than or equal to half of the first preparatory number N1.

[0221] In steps S430 and S440 , the electric valve control device 70 obtains the voltage V in response to the input of the pulse P[k] (k=1, 3, 5, 7) and stores the waveform of the voltage V in the nonvolatile memory 75 as a reference waveform of the voltage V (reference waveform table C[k]). In other words, the electric valve control device 70 sets the reference waveform of the voltage V.

[0222] When the reference waveform of the voltage V is set, the electric valve control device 70 starts a determination operation ( S450 to S500 ).

[0223] The electric valve control device 70 obtains the waveform of the voltage V ( S450 ), and calculates the difference index value sv[k] ( S460 ).

[0224] Specifically, the electric valve control device 70 obtains the voltage V in response to the input of the pulse P[k]. The electric valve control device 70 calculates the difference index value sv[k] using the waveform of the voltage V corresponding to the pulse P[k] and a reference waveform of the voltage V (reference waveform table C[k]).

[0225] The electric valve control device 70 determines whether the waveform of the voltage V is similar to the reference waveform of the voltage V at the end of the pulse P[k] ( S470 ).

[0226] Specifically, the electric valve control device 70 compares the difference index value sv[k] with the similarity determination value G. When the difference index value sv[k] is equal to or less than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used to calculate the difference index value sv[k] is similar to the reference waveform of the voltage V. When the difference index value sv[k] is greater than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used to calculate the difference index value sv[k] is not similar to the reference waveform of the voltage V.

[0227] When it is determined that the waveform of the voltage V is similar to the reference waveform of the voltage V (YES in S480 ), the electric valve control device 70 stores the waveform of the voltage V in the nonvolatile memory 75 as a new reference waveform of the voltage V ( S490 ).

[0228] When it is determined that the waveform of the voltage V is not similar to the reference waveform of the voltage V (No in S480 ), the electric valve control device 70 maintains the current reference waveform of the voltage V. In other words, the electric valve control device 70 does not update the reference waveform of the voltage V.

[0229] When the number of pulses P input to the stepping motor 66 in the first preparatory operation is smaller than the first preparatory number N1 (YES in S500 ), the electric valve control device 70 repeats the above-described operation ( S450 to S500 ).

[0230] When the number of pulses P input to the stepping motor 66 in the first preparatory operation reaches the first preparatory number N1 (No in S500 ), the electric valve control device 70 ends the first preparatory operation and starts the positioning operation.

[0231] (Positioning action)

[0232] In the positioning operation, the electric valve control device 70 inputs pulses P to the stepping motor 66 in ascending order following the first preparatory operation, thereby rotating the rotor 41 in the first direction.

[0233] The electric valve control device 70 obtains the waveform of the voltage V ( S610 ), and calculates the difference index value sv[k] ( S620 ).

[0234] Specifically, the electric valve control device 70 obtains the voltage V in response to the input of the pulse P[k]. The electric valve control device 70 calculates the difference index value sv[k] using the waveform of the voltage V corresponding to the pulse P[k] and a reference waveform of the voltage V (reference waveform table C[k]).

[0235] The electric valve control device 70 determines whether the waveform of the voltage V is similar to the reference waveform of the voltage V at the end of the pulse P[k] ( S622 ). The electric valve control device 70 performs the same operation as in step S470 in step S622 .

[0236] If it is determined that the waveform of voltage V is similar to the reference waveform of voltage V (YES in S624 ), the electric valve control device 70 stores the waveform of voltage V in the nonvolatile memory 75 as a new reference waveform of voltage V ( S626 ). The electric valve control device 70 then proceeds to step S650 .

[0237] When it is determined that the waveform of the voltage V is not similar to the reference waveform of the voltage V (No in S624 ), the electric valve control device 70 maintains the current reference waveform of the voltage V. Then, the electric valve control device 70 proceeds to step S630 .

[0238] In addition, the reference waveform setting operation ( S622 to S626 ) in the positioning operation may be omitted in Operation Example 1. In this case, the electric valve control device 70 advances the operation from step S620 to step S630 .

[0239] The electric valve control device 70 determines the state of the electric valve 5 ( S630 ).

[0240] Specifically, the electric valve control device 70 compares the difference index value sv[k] with the difference determination value H, and compares the difference index value sv[j] (j=k-2 when k=3, 5, or 7, and j=7 when k=1) calculated immediately before the difference index value sv[k] with the difference determination value H. If the difference index value sv[k] is greater than or equal to the difference determination value H and the difference index value sv[j] is greater than or equal to the difference determination value H, the electric valve control device 70 determines that the electric valve 5 is in the first rotation restricted state Sr1. When the electric valve 5 is determined to be in the first rotation restricted state Sr1, the electric valve control device 70 stores the number g immediately before j (g=j-1 when j=3, 5, or 7, and g=8 when j=1) as the start pattern number Nx in the non-volatile memory 75. When the difference index value sv[k] is smaller than the difference determination value H, or when the difference index value sv[j] is smaller than the difference determination value H, the electric valve control device 70 determines that the electric valve 5 is in the first rotation permission state Sp1 .

[0241] Alternatively, the electric valve control device 70 may determine the state of the electric valve 5 by simply comparing the difference index value sv[k] with the difference determination value H. Specifically, the electric valve control device 70 compares the difference index value sv[k] with the difference determination value H and also compares the difference index value sv[k] calculated in the period T[n] (n is a natural number) immediately preceding the period T[n-1] for which the difference index value sv[k] is present, with the difference determination value H. If the difference index value sv[k] for period T[n] is greater than or equal to the difference determination value H and the difference index value sv[k] for period T[n-1] is greater than or equal to the difference determination value H, the electric valve control device 70 determines that the electric valve 5 is in the first rotation restricted state Sr1. Alternatively, the electric valve control device 70 may determine that the electric valve 5 is in the first rotation restricted state Sr1 if the difference index values ​​sv[k] for three or more consecutive periods T are all greater than or equal to the difference determination value H. When the electric valve control device 70 determines that the electric valve 5 is in the first rotation restricted state Sr1, the electric valve control device 70 stores the previous number g (g=k-1 when k=3, 5, or 7, and g=8 when k=1) of k as the start mode number Nx in the nonvolatile memory 75. When the difference index value sv[k] for the period T[n] is less than the difference determination value H, or when the difference index value sv[k] for the period T[n-1] is less than the difference determination value H, the electric valve control device 70 determines that the electric valve 5 is in the first rotation permitted state Sp1.

[0242] When the electric valve 5 is in the first rotation-restricted state Sr1 (YES in S640), the electric valve control device 70 determines that the rotor 41 is positioned at the reference position Rx. The electric valve control device 70 then notifies the air conditioning control device 110 of the success of the initialization operation (S660) and stops inputting pulses P to the stepping motor 66 (S680). The electric valve control device 70 then completes the positioning operation (i.e., the initialization operation).

[0243] When the electric valve 5 is in the first rotation permission state Sp1 and the number of pulses P input to the stepping motor 66 in the first preparatory action and the positioning action is less than the initialization number Ni (No in S640, No in S650), the electric valve control device 70 repeats the above actions (S610 to S650).

[0244] When the electric valve 5 is in the first rotation-permitted state Sp1 and the number of pulses P input to the stepping motor 66 during the first preparatory operation and the positioning operation exceeds the initialization number Ni (No in S640, Yes in S650), the electric valve control device 70 determines that a failure has occurred in the electric valve 5. The electric valve control device 70 then notifies the air conditioning control device 110 of the failure of the initialization operation (S670) and stops inputting pulses P to the stepping motor 66 (S680). The electric valve control device 70 then terminates the positioning operation (i.e., the initialization operation).

[0245] If the initialization operation is successful, the rotor 41 is positioned at the reference position Rx. The electric valve control device 70 inputs pulses P to the stepping motor 66 in descending order to rotate the rotor 41 in the second direction while in the reference position Rx. At this time, the electric valve control device 70 inputs pulses P starting with the pulse P having the same pattern number as the starting pattern number Nx. For example, when the starting pattern number Nx is [6], the electric valve control device 70 inputs pulses P starting with pulse P[6] in descending order.

[0246] In the operation example 1, steps S430 , S450 , and S610 correspond to the voltage acquisition process, steps S440 , S490 , and S626 correspond to the reference waveform setting process, and step S630 corresponds to the state determination process.

[0247] Next, refer to Figures 27 to 30 , another example (action example 2) of the initialization operation of the electric valve control device 70 will be described.

[0248] In Operation Example 2, the nonvolatile memory 75 stores a reference waveform (reference waveform table C[k]) of the voltage V, a first reference waveform (first reference waveform table C1[k]) of the voltage V, and a second reference waveform (second reference waveform table C2[k]) of the voltage V. The first reference waveform table C1[k] and the second reference waveform table C2[k] have the same structure as the reference waveform table C[k].

[0249] Upon receiving an initialization command (S100) from the air conditioning control device 110, the electric valve control device 70 invalidates the reference waveform, first reference waveform, and second reference waveform of the voltage V stored in the non-volatile memory 75, and then performs an initialization operation. The initialization operation includes a second preparatory operation (S200), a first preparatory operation (S700), and a positioning operation (S600). In Operation Example 2, the second preparatory operation and the positioning operation are the same as in Operation Example 1, and therefore detailed descriptions are omitted.

[0250] (First preparatory action)

[0251] When the first preparatory operation is started, the reference waveform of the voltage V, the first reference waveform of the voltage V, and the second reference waveform of the voltage V are not set.

[0252] During the first preparatory operation, the electric valve control device 70 begins inputting pulses P to the stepping motor 66 in ascending order (YES in S710 and S720), thereby rotating the rotor 41 in the first direction. When the number of pulses P input to the stepping motor 66 reaches K during the first preparatory operation (NO in S720), the electric valve control device 70 acquires the waveform of the voltage V (S730) and sets a first reference waveform for the voltage V (S740). Acquisition of the voltage V waveform begins with the Kth input pulse P during the first preparatory operation.

[0253] In step S740 , the electric valve control device 70 obtains the voltage V in response to the input of the pulse P[k] (k=1, 3, 5, 7) and stores the waveform of the voltage V in the nonvolatile memory 75 as a first reference waveform of the voltage V (first reference waveform table C1[k]). In other words, the electric valve control device 70 sets the first reference waveform of the voltage V.

[0254] When the first reference waveform of the voltage V is set, the electric valve control device 70 starts a first determination operation ( S750 to S930 ).

[0255] The electric valve control device 70 obtains the waveform of the voltage V ( S750 ), and calculates a first difference index value sv1 [k] ( S760 ).

[0256] Specifically, the electric valve control device 70 obtains a voltage V in response to the input of the pulse P[k]. The electric valve control device 70 calculates a first difference index value sv1[k] using the waveform of the voltage V corresponding to the pulse P[k] and a first reference waveform (first reference waveform table C1[k]) of the voltage V. The electric valve control device 70 calculates the first difference index value sv1[k] in the same manner as the difference index value sv[k].

[0257] The electric valve control device 70 determines whether the waveform of the voltage V is similar to the first reference waveform of the voltage V at the end of the pulse P[k] ( S770 ).

[0258] Specifically, the electric valve control device 70 compares the first difference index value sv1[k] with the similarity determination value G. When the first difference index value sv1[k] is equal to or less than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used in the calculation of the first difference index value sv1[k] is similar to the first reference waveform of the voltage V. When the first difference index value sv1[k] is greater than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used in the calculation of the first difference index value sv1[k] is not similar to the first reference waveform of the voltage V.

[0259] When determining that the waveform of voltage V is similar to the first reference waveform of voltage V (YES in S780 ), the electric valve control device 70 stores the waveform of voltage V in the nonvolatile memory 75 as a new first reference waveform of voltage V ( S790 ).

[0260] When the electric valve control device 70 first determines that the waveform of voltage V is not similar to the first reference waveform of voltage V (No in S780), the electric valve control device 70 stores the waveform of voltage V as the second reference waveform of voltage V (second reference waveform table C2[k]) in the nonvolatile memory 75 (S820). In other words, the electric valve control device 70 sets the second reference waveform of voltage V.

[0261] When the number of pulses P input to the stepping motor 66 in the first preparatory operation is smaller than the first preparatory number N1 (YES in S800 ), the electric valve control device 70 repeats the above-described operation ( S750 to S800 ).

[0262] When the number of pulses P input to the stepping motor 66 in the first preparatory operation reaches the first preparatory number N1 (No in S800 ), the electric valve control device 70 sets the first reference waveform of the voltage V as the reference waveform of the voltage V ( S810 ). The electric valve control device 70 ends the first preparatory operation and starts the positioning operation.

[0263] When the second reference waveform of the voltage V is set, the electric valve control device 70 starts the second determination operation ( S830 to S930 ).

[0264] The electric valve control device 70 obtains the waveform of the voltage V ( S830 ), and calculates a first difference index value sv1 [k] and a second difference index value sv2 [k] ( S840 ).

[0265] Specifically, the electric valve control device 70 obtains the voltage V in response to the input of the pulse P[k]. The electric valve control device 70 calculates a first difference index value sv1[k] using the waveform of the voltage V corresponding to the pulse P[k] and a first reference waveform of the voltage V (first reference waveform table C1[k]). The electric valve control device 70 calculates a second difference index value sv2[k] using the waveform of the voltage V corresponding to the pulse P[k] and a second reference waveform of the voltage V (second reference waveform table C2[k]). The electric valve control device 70 calculates the first difference index value sv1[k] and the second difference index value sv2[k] in the same manner as the difference index value sv[k].

[0266] The electric valve control device 70 determines whether the waveform of the voltage V is similar to the first reference waveform of the voltage V and whether the waveform of the voltage V is similar to the second reference waveform of the voltage V at the end of the pulse P[k] ( S850 ).

[0267] Specifically, the electric valve control device 70 compares the first difference index value sv1[k] with the similarity determination value G. When the first difference index value sv1[k] is equal to or less than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used to calculate the first difference index value sv1[k] is similar to the first reference waveform of the voltage V. When the first difference index value sv1[k] is greater than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used to calculate the first difference index value sv1[k] is not similar to the first reference waveform of the voltage V.

[0268] The electric valve control device 70 compares the second difference index value sv2[k] with the similarity determination value G. When the second difference index value sv2[k] is equal to or less than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used for calculation of the second difference index value sv2[k] is similar to the second reference waveform of the voltage V. When the second difference index value sv2[k] is greater than the similarity determination value G, the electric valve control device 70 determines that the waveform of the voltage V used for calculation of the second difference index value sv2[k] is not similar to the second reference waveform of the voltage V.

[0269] When it is determined that the waveform of voltage V is similar to the first reference waveform of voltage V and the waveform of voltage V is not similar to the second reference waveform of voltage V (in S860: yes, in S870: no), the electric valve control device 70 stores the waveform of voltage V as the new first reference waveform of voltage V in the non-volatile memory 75 (S900).

[0270] When it is determined that the waveform of voltage V is not similar to the first reference waveform of voltage V and the waveform of voltage V is similar to the second reference waveform of voltage V (in S860: No, in S880: Yes), the electric valve control device 70 stores the waveform of voltage V as the new second reference waveform of voltage V in the non-volatile memory 75 (S910).

[0271] When it is determined that the waveform of voltage V is not similar to the first reference waveform of voltage V and the waveform of voltage V is not similar to the second reference waveform of voltage V (in S860: No, in S880: No), the electric valve control device 70 maintains the current first reference waveform of voltage V and maintains the current second reference waveform of voltage V.

[0272] When it is determined that the waveform of voltage V is similar to the first reference waveform of voltage V and the waveform of voltage V is similar to the second reference waveform of voltage V (in S860: yes, in S870: yes), the electric valve control device 70 determines that the waveform of voltage V is similar to both the first reference waveform and the second reference waveform of voltage V (S890).

[0273] Specifically, the electric valve control device 70 compares the first difference index sv1[k] with the second difference index sv2[k]. When the first difference index sv1[k] is less than or equal to the second difference index sv2[k] (sv1[k]≤sv2[k]), the electric valve control device 70 determines that the waveform of the voltage V is more similar to the first reference waveform of the voltage V than to the second reference waveform of the voltage V. When the first difference index sv1[k] is greater than the second difference index sv2[k] (sv1[k]>sv2[k]), the electric valve control device 70 determines that the waveform of the voltage V is more similar to the second reference waveform of the voltage V than to the first reference waveform of the voltage V.

[0274] When it is determined that the waveform of voltage V is more similar to the first reference waveform of voltage V than to the second reference waveform of voltage V (in S890: yes), the electric valve control device 70 stores the waveform of voltage V as the new first reference waveform of voltage V in the non-volatile memory 75 (S900).

[0275] When it is determined that the waveform of voltage V is more similar to the second reference waveform of voltage V than to the first reference waveform of voltage V (in S890: No), the electric valve control device 70 stores the waveform of voltage V as the new second reference waveform of voltage V in the non-volatile memory 75 (S910).

[0276] In addition, when it is determined that the waveform of the voltage V is similar to the first reference waveform of the voltage V and when it is determined that the waveform of the voltage V is similar to the second reference waveform of the voltage V (in S860: yes, in S870: yes), the electric valve control device 70 may also store the waveform of the voltage V as a new first reference waveform of the voltage V in the non-volatile memory 75, and store the waveform of the voltage V as a new second reference waveform of the voltage V in the non-volatile memory 75.

[0277] When the number of pulses P input to the stepping motor 66 in the first preparatory operation is smaller than the first preparatory number N1 (YES in S920 ), the electric valve control device 70 repeats the above-described operation ( S830 to S920 ).

[0278] When the number of pulses P input to the stepping motor 66 during the first preparatory operation reaches the first preparatory number N1 (No in S920), the electric valve control device 70 sets the first reference waveform of voltage V or the second reference waveform of voltage V, whichever has the greater number of settings, as the reference waveform of voltage V (S930). Specifically, if the number of times the waveform of voltage V is set to the first reference waveform of voltage V (the first set number of times) is greater than the number of times the waveform of voltage V is set to the second reference waveform of voltage V (the second set number of times), the electric valve control device 70 sets the first reference waveform of voltage V as the reference waveform of voltage V. If the second set number of times is greater than the first set number of times, the electric valve control device 70 sets the second reference waveform of voltage V as the reference waveform of voltage V. If the first set number of times is the same as the second set number of times, the electric valve control device 70 sets the first reference waveform of voltage V as the reference waveform of voltage V. The first set number of times is the number of times the waveform of voltage V is set to the first reference waveform of voltage V in steps S740, S790, and S900. The second set number of times is the number of times the waveform of the voltage V is set to the second reference waveform of the voltage V in steps S820 and S910 . The electric valve control device 70 completes the first preparatory operation and starts the positioning operation.

[0279] In operation example 2, steps S730 , S750 , and S830 correspond to the voltage acquisition process, steps S740 , S790 , S810 , S820 , S900 , S910 , S930 , and S626 correspond to the reference waveform setting process, and step S630 corresponds to the state determination process.

[0280] The electric valve device 1 includes an electric valve 5 and an electric valve control device 70. The electric valve 5 includes a valve body 10 having a valve port 17; a stepping motor 66 having a rotor 41 and a stator 60; a valve core 30 that faces the valve port 17 and moves toward the valve port 17 when the rotor 41 rotates in a first direction; and a stopper mechanism 49 that restricts rotation of the rotor 41 in the first direction when the rotor 41 is at a reference position Rx.

[0281] The electric valve control device 70 inputs pulses P to the stepping motor 66 to rotate the rotor 41 (rotation control unit 81). The electric valve control device 70 acquires the voltage V generated in the stator 60 by the rotation of the rotor 41 in the first direction (voltage acquisition unit 82). Based on the degree of difference between the waveform of the voltage V and a reference waveform of the voltage V, the electric valve control device 70 determines whether the electric valve 5 is in the first rotation restricted state Sr1 (state determination unit 83). The electric valve control device 70 sets the reference waveform of the voltage V (reference waveform setting unit 84). The electric valve control device 70 performs a second preparatory operation by inputting a second preparatory number N2 of pulses P to the stepping motor 66 to rotate the rotor 41 in the second direction. Following the second preparatory operation, the electric valve control device 70 performs a first preparatory operation by inputting a first preparatory number N1 of pulses P to the stepping motor 66 to rotate the rotor 41 in the first direction. The first preparatory number N1 is the same as the second preparatory number N2. The electric valve control device 70 sets the waveform of the voltage V acquired in the first preparatory operation as the reference waveform of the voltage V.

[0282] Thus, for a normally operating electric valve 5, when the electric valve control device 70 determines that the electric valve 5 is in the first rotation-restricted state Sr1, the rotor 41 is located at the reference position Rx. Therefore, by stopping the rotation of the rotor 41 in the first direction when the electric valve control device 70 determines that the electric valve 5 is in the first rotation-restricted state Sr1, the time required for initialization can be shortened. Furthermore, the generation of noise for an extended period after the rotor 41 is positioned at the reference position Rx can be suppressed.

[0283] Furthermore, the electric valve control device 70 determines the state of the electric valve 5 based on the degree of difference between the waveform of the voltage V and a reference waveform of the voltage V. Therefore, compared to a configuration that determines the state of the electric valve 5 based on the area of ​​the waveform of the voltage V or the maximum amplitude of the waveform of the voltage V, the electric valve control device 70 can determine the state of the electric valve 5 with higher accuracy. Alternatively, the electric valve control device 70 can determine the state of the electric valve 5 based on the difference between the waveform of the voltage V and a reference waveform of the voltage V. For example, the electric valve control device 70 can determine whether the electric valve 5 is in the first rotation restricted state Sr1 based on the difference between the area of ​​the waveform of the voltage V and the area of ​​the reference waveform of the voltage V, or the difference between the amplitude of the waveform of the voltage V and the amplitude of the reference waveform of the voltage V.

[0284] Furthermore, the electric valve control device 70 sets the waveform of the voltage V acquired a while after the electric valve 5 starts operating as a reference waveform of the voltage V. Therefore, the relatively stable waveform of the voltage V acquired during actual use of the electric valve 5 can be used as the reference waveform of the voltage V, and the state of the electric valve 5 can be determined with higher accuracy.

[0285] Furthermore, the electric valve control device 70 determines whether the electric valve 5 is in the first rotation-restricted state Sr1 based on the voltage V generated by the stator 60. Therefore, the electric valve control device 70 does not require a component such as a rotation angle sensor for determining the state of the electric valve 5 based on the rotation of the rotor 41, thereby simplifying the structure of the electric valve 5 and the electric valve control device 70.

[0286] Furthermore, when the electric valve control device 70 determines that the electric valve 5 is in the first rotation-restricted state Sr1, it obtains a starting pattern number Nx based on the pattern number of the first direction pulse corresponding to the waveform of the voltage V used for this determination. When rotating the rotor 41 in the second direction, while the electric valve control device 70 is at the reference position Rx, it inputs pulses P in descending order, starting with the pulses P having the same pattern number as the starting pattern number Nx. This allows the electric valve control device 70 to control the position of the rotor 41 with greater precision.

[0287] When the electric valve control device 70 begins the first preparatory operation in Operation Example 1, the reference waveform of voltage V has not yet been set. The electric valve control device 70 performs a determination operation to determine whether the waveform of voltage V obtained in the first preparatory operation is similar to the reference waveform of voltage V based on the degree of difference between the waveform and the reference waveform. After setting the reference waveform of voltage V, the electric valve control device 70 begins the determination operation. When the number of pulses P input to the stepping motor 66 during the first preparatory operation reaches K, the electric valve control device 70 sets the waveform of voltage V obtained by the electric valve control device 70 as the reference waveform of voltage V. If the determination operation determines that the waveform of voltage V is similar to the reference waveform of voltage V, the electric valve control device 70 sets the waveform of voltage V used for this determination to the reference waveform of voltage V. If the determination operation determines that the waveform of voltage V is not similar to the reference waveform of voltage V, the electric valve control device 70 maintains the reference waveform of voltage V. This allows the electric valve control device 70 to set a reference waveform of voltage V suitable for the electric valve 5.

[0288] Following the first preparatory operation, the electric valve control device 70 performs a positioning operation to input pulses P to the stepping motor 66, thereby rotating the rotor 41 in the first direction. In Operation Example 1, the electric valve control device 70 performs a determination operation during both the first preparatory operation and the positioning operation. This allows the more stable waveform of voltage V, obtained during actual use of the electric valve 5, to be used as the reference waveform for voltage V, enabling the determination of the state of the electric valve 5 with greater accuracy.

[0289] Furthermore, during the determination operation, the electric valve control device 70 calculates a difference index value sv indicating the degree of difference between the waveform of the voltage V and a reference waveform of the voltage V, and determines whether the waveform of the voltage V is similar to the reference waveform of the voltage V based on a comparison result of the difference index value sv and a similarity determination value G. Thus, the electric valve control device 70 can set a reference waveform of the voltage V that is more suitable for the electric valve 5 .

[0290] The reference waveform of voltage V is a data table associated with time t and a reference voltage rv at that time t, set for the first direction pulse. When the first direction pulse is input to the stepping motor 66, the electric valve control device 70 acquires voltage V in a time series. When voltage v (voltage V) is acquired at acquisition time tv corresponding to the input of the first direction pulse, the electric valve control device 70 calculates an intermediate value dv2, which is the value obtained by squaring the difference dv between voltage v and reference voltage rv. Reference voltage rv is the voltage associated with time t corresponding to acquisition time tv in the data table set for the first direction pulse input to the stepping motor 66. The electric valve control device 70 calculates a difference index sv by adding together the multiple intermediate values ​​dv2 calculated using voltage v acquired in response to the input of the first direction pulse. The difference index sv is calculated using the above-mentioned mathematical formula (1). Thus, unlike the area and maximum amplitude of the waveform, the difference index sv can appropriately reflect the degree of difference in the waveform shape. Therefore, the electric valve control device 70 can determine the state of the electric valve 5 with higher accuracy.

[0291] In addition, the difference index value sv is not limited to being calculated using the above-mentioned mathematical formula (1). The difference index value may also be, for example, an index value related to the change in the magnitude of the voltage V at each acquisition time tv. Specifically, if the voltage v is acquired at the acquisition time tv corresponding to the input of the first direction pulse, the electric valve control device 70 calculates the difference dv between the voltage v and the reference voltage rv, which is the voltage associated with the time t corresponding to the acquisition time tv in the data table set for the pulse P input to the stepping motor 66. The difference dv is calculated as an absolute value. The electric valve control device 70 uses the number of the plurality of difference values ​​dv calculated using the voltage v acquired corresponding to the input of the pulse P that is greater than the specified differential judgment value as the difference index value. Such a difference index value also appropriately reflects the degree of difference in the shape of the waveform. In addition, the difference index value may also be an index value related to the change in the slope of the voltage V at each acquisition time tv. The difference index value is preferably a value reflecting the time series element.

[0292] Furthermore, the electric valve control device 70 calculates the difference index value sv by summing a plurality of intermediate values ​​dv2 calculated using the voltage v acquired during a second period p2, which is a portion of the period from the beginning to the end of the first directional pulse. The voltage component of the voltage v during the second period p2, which is related to the back electromotive force caused by the inductance of the stator 60, is smaller than the voltage component of the voltage v, which is related to the electromagnetic induction caused by the rotation of the rotor 41. As a result, the proportion of the latter voltage component in the voltage v becomes relatively larger, allowing the electric valve control device 70 to determine the state of the electric valve 5 with higher accuracy.

[0293] When the electric valve control device 70 begins the first preparatory operation in Operation Example 2, the first and second reference waveforms of voltage V have not yet been set. The electric valve control device 70 performs a first determination operation to determine whether the waveform of voltage V acquired in the first preparatory operation is similar to the first reference waveform of voltage V based on the degree of difference between the waveform of voltage V acquired in the first preparatory operation and the first reference waveform of voltage V. The electric valve control device 70 performs a second determination operation to determine whether the waveform of voltage V acquired in the first preparatory operation is similar to the second reference waveform of voltage V based on the degree of difference between the waveform of voltage V acquired in the first preparatory operation and the second reference waveform of voltage V. The electric valve control device 70 begins the first determination operation after setting the first reference waveform of voltage V. The electric valve control device 70 begins the second determination operation after setting the second reference waveform of voltage V. When the number of pulses P input to the stepping motor 66 during the first preparatory operation reaches K, the electric valve control device 70 sets the waveform of voltage V acquired by the electric valve control device 70 to the first reference waveform of voltage V. If the waveform of the voltage V is determined to be similar to the first reference waveform of the voltage V in the first determination operation, the electric valve control device 70 sets the waveform of the voltage V used for this determination to the first reference waveform of the voltage V. If the waveform of the voltage V is determined to be dissimilar to the first reference waveform of the voltage V in the first determination operation, the electric valve control device 70 maintains the first reference waveform of the voltage V. If the waveform of the voltage V is determined to be dissimilar to the first reference waveform of the voltage V for the first time in the first determination operation, the electric valve control device 70 sets the waveform of the voltage V used for this determination to the second reference waveform of the voltage V. If the waveform of the voltage V is determined to be similar to the second reference waveform of the voltage V in the second determination operation, the electric valve control device 70 sets the waveform of the voltage V used for this determination to the second reference waveform of the voltage V. If the waveform of the voltage V is determined to be dissimilar to the second reference waveform of the voltage V in the second determination operation, the electric valve control device 70 maintains the second reference waveform of the voltage V. At the end of the first preparatory operation, if the first set number of times is greater than the second set number of times, the electric valve control device 70 sets the first reference waveform of voltage V as the reference waveform of voltage V. If the second set number of times is greater than the first set number of times, the electric valve control device 70 sets the second reference waveform of voltage V as the reference waveform of voltage V. The first set number of times is the number of times the waveform of voltage V is set to the first reference waveform of voltage V. The second set number of times is the number of times the waveform of voltage V is set to the second reference waveform of voltage V. Thus, the electric valve control device 70 can set a reference waveform of voltage V suitable for the electric valve 5. Furthermore, if the first set number of times is the same as the second set number of times, the electric valve control device 70 sets the first reference waveform of voltage V as the reference waveform of voltage V. Alternatively, if the first set number of times is the same as the second set number of times, the electric valve control device 70 may set the second reference waveform of voltage V as the reference waveform of voltage V.

[0294] Furthermore, in Action Example 2, the electric valve control device 70 performs a determination operation to determine whether the waveform of the voltage V obtained during the positioning operation is similar to the reference waveform of the voltage V based on the degree of difference between the waveform of the voltage V obtained during the positioning operation and the reference waveform of the voltage V. If the positioning operation begins, the electric valve control device 70 begins the determination operation. If the determination operation determines that the waveform of the voltage V is similar to the reference waveform of the voltage V, the electric valve control device 70 sets the waveform of the voltage V used for the determination as the reference waveform of the voltage V. If the determination operation determines that the waveform of the voltage V is not similar to the reference waveform of the voltage V, the electric valve control device 70 maintains the reference waveform of the voltage V. Thus, a more stable waveform of the voltage V obtained during actual use of the electric valve 5 can be set as the reference waveform of the voltage V, and the state of the electric valve 5 can be determined with higher accuracy.

[0295] Furthermore, when it is determined in the first determination operation that the waveform of the voltage V is similar to the first reference waveform of the voltage V and in the second determination operation that the waveform of the voltage V is similar to the second reference waveform of the voltage V, (1) when the waveform of the voltage V used for the determination is more similar to the first reference waveform of the voltage V than to the second reference waveform of the voltage V, the electric valve control device 70 sets the waveform of the voltage V used for the determination to the first reference waveform of the voltage V, and (2) when the waveform of the voltage V used for the determination is more similar to the second reference waveform of the voltage V than to the first reference waveform of the voltage V, the electric valve control device 70 sets the waveform of the voltage V used for the determination to the second reference waveform of the voltage V. Thus, it is possible to avoid having one waveform of the voltage V be set to both the first reference waveform of the voltage V and the second reference waveform of the voltage V.

[0296] Furthermore, in the first determination operation, the electric valve control device 70 calculates a first difference index value sv1 indicating the degree of difference between the waveform of the voltage V and the first reference waveform of the voltage V, and determines whether the waveform of the voltage V is similar to the first reference waveform of the voltage V based on a comparison result between the first difference index value sv1 and the similarity determination value G. In the second determination operation, the electric valve control device 70 calculates a second difference index value sv2 indicating the degree of difference between the waveform of the voltage V and the second reference waveform of the voltage V, and determines whether the waveform of the voltage V is similar to the second reference waveform of the voltage V based on a comparison result between the second difference index value sv2 and the similarity determination value G. Thus, the electric valve control device 70 can set the first reference waveform of the voltage V, the second reference waveform of the voltage V, and the reference waveform of the voltage V that are more suitable for the electric valve 5.

[0297] Alternatively, the electric valve control device 70 may perform the second preparatory operation and the first preparatory operation multiple times and set the waveform of the voltage V obtained in the last first preparatory operation as the reference waveform of the voltage V. This allows the electric valve 5 to be sufficiently heated, and a more stable waveform of the voltage V to be set as the reference waveform of the voltage V.

[0298] Following the first preparatory operation, the electric valve control device 70 performs a positioning operation in which pulses P are input to the stepping motor 66 to rotate the rotor 41 in the first direction. If, during the positioning operation, the electric valve control device 70 determines that the electric valve 5 is in the first rotation-restricted state Sr1, it stops inputting pulses P to the stepping motor 66. If the number of pulses P input to the stepping motor 66 during the first preparatory operation and the positioning operation exceeds the initialization number Ni, the electric valve control device 70 determines that a failure has occurred in the electric valve 5. This allows the electric valve control device 70 to simply and quickly stop the rotation of the rotor 41 in the first direction, compared to a configuration in which, for example, the air conditioning control device 110 is notified of the first rotation-restricted state Sr1 and the initialization operation is stopped by a stop command from the air conditioning control device 110. Furthermore, the electric valve control device 70 can detect a failure in the electric valve 5.

[0299] Furthermore, the stator 60 includes an A-phase stator 61 and a B-phase stator 62. The electric valve control device 70 obtains the voltage VB generated in the B-phase stator 62 when a drive current is supplied only to the A-phase stator 61, and obtains the voltage VA generated in the A-phase stator 61 when a drive current is supplied only to the B-phase stator 62. Consequently, the electric valve control device 70 does not need to separate the voltage component related to electromagnetic induction from the voltage generated in the A-phase stator 61, nor does it need to separate the voltage component related to electromagnetic induction from the voltage generated in the B-phase stator 62. Therefore, the voltages VA and VB can be obtained using a relatively simple configuration.

[0300] Voltage and current are closely related. Therefore, the electric valve control device 70 can also use the current generated in the stator 60 by the rotation of the rotor 41 instead of the voltage generated in the stator 60 by the rotation of the rotor 41 to perform Operation Example 1 and Operation Example 2. Even in the configuration using the current waveform, the same functions and effects as the configuration using the voltage waveform can be achieved.

[0301] In this specification, terms such as "cylindrical" and "cylindrical" may also be used to refer to components or parts of components that substantially have the shape of the term. For example, "a cylindrical component" includes both cylindrical components and substantially cylindrical components. Furthermore, in this specification, the term "identical" may include both strictly identical and substantially identical components.

[0302] While the embodiments of the present invention have been described above, the present invention is not limited to the embodiments. A person skilled in the art may appropriately add, delete, or modify the design of the aforementioned embodiments, or appropriately combine the features of the embodiments, and such additions, deletions, or modifications are all within the scope of the present invention, as long as they do not violate the spirit of the present invention.

Claims

1. An electric valve control device for controlling an electric valve, the electric valve comprising: a valve body having a valve port; a stepping motor having a rotor and a stator; a valve core opposite the valve port, the valve core moving toward the valve port when the rotor rotates in a first direction; and a stop mechanism for limiting the rotation of the rotor in the first direction when the rotor is in a reference position, wherein: have: a rotation control unit that inputs pulses to the stepping motor to rotate the rotor; a voltage acquisition unit configured to acquire a voltage generated on the stator by the rotor rotating in the first direction; a state determination unit that determines, based on a difference between the waveform of the voltage and a reference waveform of the voltage, whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted; as well as a reference waveform setting unit that sets a reference waveform of the voltage, The rotation control unit performs a second preparatory operation of inputting a second preparatory number of pulses to the stepping motor to rotate the rotor in a second direction. Following the second preparatory operation, the rotation control unit performs a first preparatory operation of inputting a first preparatory number of pulses less than the second preparatory number to the stepping motor to rotate the rotor in the first direction. The reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation as a reference waveform of the voltage.

2. The electric valve control device according to claim 1, characterized in that: When the rotation control unit starts the first preparatory operation, the voltage reference waveform has not yet been set. After the reference waveform setting unit sets the reference waveform of the voltage, the state determination unit starts a determination operation of determining whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation is similar to the reference waveform of the voltage. If the number of pulses input to the stepping motor in the first preparatory operation reaches K, the reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit as the reference waveform of the voltage. When the state determination unit determines in the determination operation that the waveform of the voltage is similar to the reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the reference waveform of the voltage. When the state determination unit determines in the determination operation that the waveform of the voltage is not similar to the reference waveform of the voltage, the reference waveform setting unit maintains the reference waveform of the voltage. Here, K is a natural number greater than 1.

3. The electric valve control device according to claim 2, characterized in that: Following the first preparatory operation, the rotation control unit performs a positioning operation of inputting a pulse to the stepping motor to rotate the rotor in the first direction. The state determination unit performs the determination operation of determining whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation and the positioning operation is similar to a reference waveform of the voltage.

4. The electric valve control device according to claim 2 or 3, characterized in that: The state determination unit calculates a difference index value indicating the degree of difference between the voltage waveform and the voltage reference waveform in the determination operation, and determines whether the voltage waveform is similar to the voltage reference waveform based on a comparison result of the difference index value and a similarity determination value.

5. The electric valve control device according to claim 4, characterized in that: The voltage reference waveform is a data table that associates a time with a reference voltage at that time, which is set for a first direction pulse. The first direction pulse is a pulse input to the stepping motor to rotate the rotor in the first direction. When the first direction pulse is input to the stepping motor, the voltage acquisition unit acquires the voltage in a time series manner. If the voltage acquisition unit acquires the voltage at an acquisition time corresponding to the input of the first direction pulse, the state determination unit calculates an intermediate value, the intermediate value being a value obtained by squaring a difference between the voltage and the reference voltage, the reference voltage being a voltage associated with the time corresponding to the acquisition time in the data table set for the first direction pulse input to the stepping motor. The state determination unit calculates the difference index value by adding a plurality of intermediate values ​​calculated using the voltage acquired by the voltage acquisition unit in response to input of the first direction pulse.

6. The electric valve control device according to claim 5, characterized in that: The state determination unit calculates the difference index value by adding a plurality of intermediate values ​​calculated using the voltage acquired by the voltage acquisition unit during a portion of a period from the beginning to the end of the first direction pulse. A voltage component related to the back electromotive force caused by the inductance of the stator included in the voltage during a portion of the period is smaller than a voltage component related to the electromagnetic induction caused by the rotation of the rotor included in the voltage.

7. The electric valve control device according to claim 1, characterized in that: When the rotation control unit starts the first preparatory operation, the first reference waveform of the voltage and the second reference waveform of the voltage have not yet been set. After the reference waveform setting unit sets the first reference waveform of the voltage, the state determination unit starts a first determination operation to determine whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation is similar to the first reference waveform of the voltage. After the reference waveform setting unit sets the second reference waveform of the voltage, the state determination unit starts a second determination operation, the second determination operation determining whether the waveform of the voltage acquired by the voltage acquisition unit in the first preparatory operation is similar to the second reference waveform of the voltage. If the number of pulses input to the stepping motor in the first preparatory operation reaches K, the reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit as the first reference waveform of the voltage. When the state determination unit determines in the first determination operation that the waveform of the voltage is similar to the first reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the first reference waveform of the voltage. When the state determination unit determines in the first determination operation that the waveform of the voltage is not similar to the first reference waveform of the voltage, the reference waveform setting unit maintains the first reference waveform of the voltage. When the state determination unit determines for the first time in the first determination operation that the waveform of the voltage is not similar to the first reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination to the second reference waveform of the voltage. When the state determination unit determines in the second determination operation that the waveform of the voltage is similar to the second reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the second reference waveform of the voltage. When the state determination unit determines in the second determination operation that the waveform of the voltage is not similar to the second reference waveform of the voltage, the reference waveform setting unit maintains the second reference waveform of the voltage. When the first preparatory operation is completed, the reference waveform setting unit sets the first reference waveform of the voltage as the reference waveform of the voltage when the number of times the voltage waveform is set to the first reference waveform of the voltage is greater than the number of times the voltage waveform is set to the second reference waveform of the voltage, and sets the second reference waveform of the voltage as the reference waveform of the voltage when the number of times the voltage waveform is set to the second reference waveform of the voltage is greater than the number of times the voltage waveform is set to the first reference waveform of the voltage. Here, K is a natural number greater than 1.

8. The electric valve control device according to claim 7, characterized in that: Following the first preparatory operation, the rotation control unit performs a positioning operation of inputting a pulse to the stepping motor to rotate the rotor in the first direction. When the positioning operation starts, the state determination unit starts a determination operation to determine whether the waveform of the voltage acquired by the voltage acquisition unit during the positioning operation is similar to a reference waveform of the voltage. When the state determination unit determines in the determination operation that the waveform of the voltage is similar to the reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination as the reference waveform of the voltage. When the state determination unit determines in the determination operation that the waveform of the voltage is not similar to the reference waveform of the voltage, the reference waveform setting unit maintains the reference waveform of the voltage.

9. The electric valve control device according to claim 7, characterized in that: When the state determination unit determines that the waveform of the voltage is similar to the first reference waveform of the voltage in the first determination action and determines that the waveform of the voltage is similar to the second reference waveform of the voltage in the second determination action, (1) when the waveform of the voltage used for the determination is more similar to the first reference waveform of the voltage than to the second reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination to the first reference waveform of the voltage, and (2) when the waveform of the voltage used for the determination is more similar to the second reference waveform of the voltage than to the first reference waveform of the voltage, the reference waveform setting unit sets the waveform of the voltage used for the determination to the second reference waveform of the voltage.

10. The electric valve control device according to claim 7, characterized in that: In the first determination operation, the state determination unit calculates a first difference index value indicating the degree of difference between the waveform of the voltage and a first reference waveform of the voltage, and determines whether the waveform of the voltage is similar to the first reference waveform of the voltage based on a comparison result of the first difference index value and a similarity determination value. In the second determination operation, the state determination unit calculates a second difference index value indicating the degree of difference between the waveform of the voltage and a second reference waveform of the voltage, and determines whether the waveform of the voltage is similar to the second reference waveform of the voltage based on a comparison result of the second difference index value and the similarity determination value.

11. The electric valve control device according to claim 1, characterized in that: The rotation control unit performs the second preparatory operation and the first preparatory operation multiple times. The reference waveform setting unit sets the waveform of the voltage acquired by the voltage acquisition unit in the last first preparatory operation as the reference waveform of the voltage.

12. The electric valve control device according to claim 1, characterized in that: Following the first preparatory operation, the rotation control unit performs a positioning operation of inputting a pulse to the stepping motor to rotate the rotor in the first direction. When the state determination unit determines that the electric valve is in the first rotation restricted state during the positioning operation, the rotation control unit stops inputting pulses to the stepping motor. The state determination unit determines that the electric valve has failed when the number of pulses input to the stepping motor in the first preparatory operation and the positioning operation exceeds an initialization number that is sufficient to position the rotor to the reference position.

13. The electric valve control device according to claim 1, characterized in that: The stator has an A-phase stator and a B-phase stator, The voltage acquisition unit acquires the voltage generated in the stepping motor when a drive current is supplied to only one of the A-phase stator and the B-phase stator in response to the input of the pulse from the rotation control unit to the stepping motor.

14. An electric valve control device for controlling an electric valve, the electric valve comprising: a valve body having a valve port; a stepping motor having a rotor and a stator; a valve core opposite the valve port, the valve core moving toward the valve port when the rotor rotates in a first direction; and a stop mechanism for limiting the rotation of the rotor in the first direction when the rotor is in a reference position, characterized in that: have: a rotation control unit that inputs pulses to the stepping motor to rotate the rotor; a current acquisition unit configured to acquire a current generated in the stator by the rotor rotating in the first direction; a state determination unit that determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted based on a difference between the waveform of the current and a reference waveform of the current; as well as a reference waveform setting unit that sets a reference waveform of the current, The rotation control unit performs a second preparatory operation of inputting a second preparatory number of pulses to the stepping motor to rotate the rotor in a second direction. Following the second preparatory operation, the rotation control unit performs a first preparatory operation of inputting a first preparatory number of pulses less than the second preparatory number to the stepping motor to rotate the rotor in the first direction. The reference waveform setting unit sets the waveform of the current acquired by the current acquisition unit in the first preparatory operation as a reference waveform of the current.

15. An electric valve device, characterized in that: have: The electric valve control device according to claim 1 or claim 14; and The electric valve.

16. A method for controlling an electric valve, the electric valve comprising: a valve body having a valve port; a stepping motor having a rotor and a stator; a valve core opposite the valve port, the valve core moving toward the valve port when the rotor rotates in a first direction; and a stop mechanism for limiting the rotation of the rotor in the first direction when the rotor is in a reference position, wherein: Include: a second preparation step of inputting a second preparation number of pulses into the stepping motor to rotate the rotor in a second direction; a first preparation step, followed by the second preparation step, inputting a first preparation number of pulses less than the second preparation number into the stepping motor to rotate the rotor in the first direction; A positioning step, subsequent to the first preparation step, inputting pulses to the stepping motor to rotate the rotor in the first direction; a voltage obtaining step of obtaining a voltage generated on the stator by the rotation of the rotor in the first direction; a reference waveform setting step of setting the voltage waveform obtained in the first preparation step as the voltage reference waveform; as well as The state determining step determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted, based on a difference between the voltage waveform acquired in the positioning step and a reference voltage waveform.

17. A method for controlling an electric valve, the electric valve comprising: a valve body having a valve port; a stepping motor having a rotor and a stator; a valve core opposite the valve port, the valve core moving toward the valve port when the rotor rotates in a first direction; and a stop mechanism for limiting the rotation of the rotor in the first direction when the rotor is in a reference position, wherein: Include: a second preparation step of inputting a second preparation number of pulses into the stepping motor to rotate the rotor in a second direction; a first preparation step, followed by the second preparation step, inputting a first preparation number of pulses less than the second preparation number into the stepping motor to rotate the rotor in the first direction; A positioning step, subsequent to the first preparation step, inputting pulses to the stepping motor to rotate the rotor in the first direction; a current acquiring step of acquiring a current generated in the stator by the rotation of the rotor in the first direction; a reference waveform setting step of setting the waveform of the current obtained in the first preparation step as a reference waveform of the current; as well as The state determining step determines whether the electric valve is in a first rotation restricted state in which rotation of the rotor in the first direction is restricted, based on a difference between the waveform of the current acquired in the positioning step and a reference waveform of the current.

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