JP7172158B2 - Motor control device, integrated valve device and heat exchanger - Google Patents

Description

TECHNICAL FIELD The present invention relates to a motor control device, an integrated valve device and a heat exchanger.

As an integrated valve device provided in a refrigeration cycle device for a vehicle, for example, one disclosed in Patent Document 1 includes a single motor and a plurality of valves that are opened and closed based on the rotational driving force of the motor. . The plurality of valves are opened and closed by axial engagement with a shaft portion that moves in the axial direction based on the drive of the motor. The refrigerant flow is switched between the heating mode and the cooling mode of the refrigeration cycle device by opening and closing the plurality of valves. Further, the motor control device provided in the integrated valve device stores the position where the shaft hits the end of the movable range as the origin position, and controls the motor while ascertaining the position of the shaft with reference to the origin position.

JP 2017-187255 A

In the integrated valve system as described above, in order to correct the deviation between the position where the shaft hits the end of the movable range and the origin position stored in the motor controller, the shaft is moved to the end of the movable range. Although it is desirable that the initializing process is executed by intentionally bumping to update the origin position, there is a risk of damage to the shaft or the other side of the bumping due to the load at the time of bumping in the initializing process.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to reduce the load applied to the shaft and the other side of the abutment when the shaft is abutted in the initialization process. An object of the present invention is to provide a motor control device, an integrated valve device and a heat exchanger.

A motor control device that solves the above problems is a single motor, a shaft portion that moves in its own axial direction based on the drive of the motor, and a plurality of shaft portions that are opened and closed by engaging the shaft portion in the axial direction. The motor of an integrated valve device comprising a valve main body having a valve is stored as an origin position, and the position at which the shaft hits the end of the movable range is stored as an origin position, and the origin position is used as a reference. A motor control device for controlling the motor while grasping the position of a shaft portion, wherein initialization updates the origin position by moving the shaft portion toward the origin position side and abutting the end portion of the range of motion. In the processing, a section up to a set position set before the origin position is defined as a first section, a section from the set position to the origin position is defined as a second section, and the rotational torque of the motor in the second section is calculated as , lower than the rotational torque of the motor in the first section.

According to the above aspect, when the shaft portion is driven in the initialization process, the rotational torque of the motor is reduced in the second section on the origin position side from the set position. As a result, the load applied when the shaft hits the end of the movable range in the initialization process can be reduced.

In the motor control device described above, the number of rotations of the motor in the second interval is set higher than the number of rotations of the motor in the first interval.
According to the above aspect, in the initialization process, the rotational torque of the motor in the second section can be made lower than the rotational torque of the motor in the first section.

In the above motor control device, the motor is a stepping motor, and the number of revolutions of the motor in the second interval is set to be equal to or higher than the maximum self-starting frequency of the motor and equal to or lower than the maximum response frequency.

According to the above aspect, the pull-in torque of the motor after the shaft hits the end of the range of motion can be reduced to almost zero. can be reduced.

In the above motor control device, the current value of the drive current supplied to the motor is made lower in the second section than in the first section.
According to the above aspect, in the initialization process, the rotational torque of the motor in the second section can be made lower than the rotational torque of the motor in the first section.

An integrated valve device that solves the above problems is an integrated valve device that is provided in a refrigeration cycle device for a vehicle, and includes a motor, a shaft portion that moves in its own axial direction based on the drive of the motor, and the shaft portion. A valve main body portion having a plurality of valves that are opened and closed by engagement in the axial direction of the valve, and the above-described motor control device are integrally provided.

According to the above aspect, in the integrated valve device integrally provided with the motor control device, when the shaft portion is hit in the initialization process, the load applied to the shaft portion and the other side of the hit can be reduced.

A heat exchanger that solves the above problems is a heat exchanger that constitutes a part of a refrigeration cycle device for a vehicle, and is integrally provided with the integrated valve device.
According to the above aspect, in the heat exchanger integrally provided with the integrated valve device including the motor control device, when the shaft portion is abutted in the initialization process, the load applied to the shaft portion and the abutment counterpart side can be reduced. can be done.

According to the motor control device, the integrated valve device, and the heat exchanger of the present invention, the load applied to the shaft portion and the other side of the abutment can be reduced when the shaft portion is abutted in the initialization process.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows the refrigerating-cycle apparatus provided with the heat exchanger of embodiment. The schematic cross section which shows the integrated valve apparatus of the same form. (a) Explanatory drawing for demonstrating the behavior in the heating mode in the refrigerating-cycle apparatus of the same form, (b) Schematic sectional drawing for demonstrating operation|movement of the integrated valve apparatus in the heating mode. (a) Explanatory drawing for demonstrating the behavior at the time of the cooling mode in the refrigerating-cycle apparatus of the same form, (b) Schematic sectional drawing for demonstrating the operation|movement of the integrated valve apparatus at the time of the cooling mode. 4 is a graph showing the opening area of each channel according to the axial position (number of pulses) of the shaft. (a) and (b) are graphs for explaining the control mode of the drive current control section when switching from the cooling mode to the heating mode in the same embodiment. (a) and (b) are graphs for explaining the control mode of the drive current control section in the same initialization process. The graph which shows the output characteristic according to the rotation speed (driving frequency) of the motor in the same form. 7A and 7B are graphs for explaining the control mode of the drive current control unit in the initialization process of the modified example; 7A and 7B are graphs for explaining the control mode of the drive current control unit in the initialization process of the modified example; 9 is a graph for explaining the control mode of the drive current control section in the initialization process of the modified example;

Hereinafter, one embodiment of a motor control device, an integrated valve device, and a heat exchanger will be described with reference to the drawings. In the drawings, for convenience of explanation, part of the configuration may be exaggerated or simplified. Also, the dimensional ratio of each part may differ from the actual one.

As shown in FIG. 1, the heat exchanger 10 of the present embodiment is used in a refrigeration cycle device D (heat pump cycle device) for air conditioning of electric vehicles (hybrid vehicles, EV vehicles, etc.). A vehicle air conditioner equipped with a refrigeration cycle device D can switch between a cooling mode in which air cooled by the evaporator 14 is blown into the passenger compartment and a heating mode in which air warmed by a heater core (not shown) is sent into the passenger compartment. It is configured. In addition, the refrigerant circulation circuit Da of the refrigeration cycle device D is configured to be switchable between a circulation circuit corresponding to the cooling mode and a circulation circuit corresponding to the heating mode. As the refrigerant that flows through the refrigerant circulation circuit Da of the refrigeration cycle device D, for example, an HFC-based refrigerant or an HFO-based refrigerant can be used. Moreover, the refrigerant preferably contains oil for lubricating the compressor 11 .

The refrigeration cycle device D includes a compressor 11, a water-cooled condenser 12, a heat exchanger 10, an expansion valve 13, and an evaporator 14 (evaporator) in the refrigerant circulation circuit Da.

The compressor 11 is an electric compressor arranged in the engine room outside the passenger compartment. to dispense. The high-temperature, high-pressure gas-phase refrigerant discharged from the compressor 11 flows into the water-cooled condenser 12 . As the compression mechanism of the compressor 11, various compression mechanisms such as a scroll compression mechanism and a vane compression mechanism can be used. Further, the compressor 11 is adapted to control the refrigerant discharge capacity by controlling the motor as its drive source.

The water-cooled condenser 12 is a well-known heat exchanger, and includes a first heat exchange section 12a provided on the refrigerant circulation circuit Da and a second heat exchange section provided on the cooling water circulation circuit C in the cooling water circulation device. 12b. In addition, the heater core is provided on the circulation circuit C. As shown in FIG. The water-cooled condenser 12 exchanges heat between the gas-phase refrigerant flowing in the first heat exchange section 12a and the cooling water flowing in the second heat exchange section 12b. That is, in the water-cooled condenser 12, the cooling water in the second heat exchange portion 12b is heated by the heat of the vapor phase refrigerant in the first heat exchange portion 12a, while the vapor phase refrigerant in the first heat exchange portion 12a is cooled. It is designed to be Therefore, the water-cooled condenser 12 serves as a radiator for indirectly dissipating the heat of the refrigerant discharged from the compressor 11 and flowing into the first heat exchange portion 12a to the blast air of the vehicle air conditioner through the cooling water and the heater core. Function.

The vapor-phase refrigerant that has passed through the first heat exchange portion 12a of the water-cooled condenser 12 flows into the heat exchanger 10 via an integrated valve device 24, which will be described later. The heat exchanger 10 is an outdoor heat exchanger arranged on the front side of the vehicle in the engine room outside the passenger compartment. It is to exchange heat with (outside air).

The expansion valve 13 is a temperature sensitive mechanical expansion valve that decompresses and expands the liquid-phase refrigerant supplied from the heat exchanger 10 . The expansion valve 13 decompresses the low-temperature, high-pressure liquid-phase refrigerant and supplies the refrigerant to the evaporator 14 .

The evaporator 14 is a cooling heat exchanger (evaporator) that cools the blown air in the cooling mode. The liquid-phase refrigerant supplied from the expansion valve 13 to the evaporator 14 exchanges heat with the air around the evaporator 14 (inside the duct of the vehicle air conditioner). This heat exchange evaporates the liquid-phase refrigerant and cools the air around the evaporator 14 . After that, the refrigerant in the evaporator 14 is discharged toward the compressor 11 and compressed again by the compressor 11 .

[Configuration of heat exchanger]
The heat exchanger 10 includes a first heat exchange section 21 and a second heat exchange section 22 functioning as a supercooler. Furthermore, the heat exchanger 10 is constructed integrally with a liquid reservoir 23 connected to the first and second heat exchange sections 21 and 22 and an integrated valve device 24 provided in the liquid reservoir 23 . The inflow path 21 a and the outflow path 21 b of the first heat exchange section 21 communicate with the integrated valve device 24 . Also, the inflow passage 22 a of the second heat exchange section 22 communicates with the reservoir 23 and the integrated valve device 24 .

The first heat exchange section 21 functions as a condenser or an evaporator depending on the temperature of the refrigerant flowing inside. The reservoir 23 is configured to separate the gas-phase refrigerant and the liquid-phase refrigerant, and to store the separated liquid-phase refrigerant in the reservoir 23 . The second heat exchange unit 22 exchanges heat between the liquid-phase refrigerant flowing from the reservoir 23 and the outside air, thereby further cooling the liquid-phase refrigerant to increase the degree of supercooling of the refrigerant, and The refrigerant after exchange is made to flow to the expansion valve 13 . The first heat exchanging part 21, the second heat exchanging part 22, and the reservoir 23 are integrally formed by being connected to each other, for example, by bolting.

[Configuration of integrated valve device]
As shown in FIG. 2, the integrated valve device 24 includes a valve body 25 arranged in the reservoir 23, a single motor 26 for driving the valve body 25, and a valve body through the motor 26. 25 and a pair of pressure sensors (first and second pressure sensors 28, 29). A circuit board that constitutes the integrated valve ECU 27 is provided integrally with the motor 26 . A stepping motor or the like is used as the motor 26, for example.

The valve main body 25 includes a housing 30 inside which a refrigerant can flow, and first to third valves 31 to 33 provided in the housing 30 . A motor 26 is provided integrally with the housing 30 .

The housing 30 has a first flow path 41 (high-pressure flow path) having a first inlet 41a and a first outlet 41b, and a second flow path from a second inlet 42a to a second outlet 42b. A channel 42 and a third channel 43 (see FIG. 4(b)), which is a channel from the second inlet 42a to the third outlet 43b, are formed.

A first inlet 41a of the first flow path 41 is connected to the discharge side of the water-cooled condenser 12 (first heat exchange section 12a), and a first outlet 41b of the first flow path 41 is connected to the first heat exchange section 21. It is connected to the inflow passage 21a of (the heat exchanger 10). That is, the first flow path 41 is configured as a high-pressure flow path through which the high-pressure refrigerant discharged from the compressor 11 passes.

The second inlet 42 a is connected to the outlet passage 21 b of the first heat exchange section 21 . The second outflow port 42b is connected to the inflow side of the compressor 11 . The third outflow port 43b communicates with the inflow path 22a of the second heat exchange section 22 (heat exchanger 10) through the inside of the liquid reservoir 23. As shown in FIG.

A first valve 31 (high-pressure valve) is provided in the first flow path 41 to open and close the first flow path 41 . Also, the second valve 32 is provided in the second flow path 42 to open and close the second flow path 42 . A third valve 33 is provided in the third flow path 43 to open and close the third flow path 43 .

The valve body portion 25 includes a shaft portion 44 in the housing 30 for driving the first to third valves 31 to 33 . The shaft portion 44 is coaxially and drivingly connected to the motor 26 and is configured to advance and retreat in the axial direction based on the driving force of the motor 26 . In the following, for convenience of explanation, the axial side of the shaft portion 44 toward the motor 26 (axial base end side) is defined as the upper side, and the axial direction opposite to the motor side (axial distal end side) of the shaft portion 44 is defined as the lower side. explain.

The first valve 31 includes a first valve body 51 axially engageable with the shaft portion 44 and a first valve seat 52 fixed to the housing 30 . The first valve body 51 has a through hole 51a through which the shaft portion 44 is inserted. The first valve body 51 is axially biased toward the first valve seat 52 by a first biasing member 53 (compression coil spring).

The first valve body 51 has a variable throttle valve 54 . The variable throttle valve 54 includes a flange-shaped variable throttle valve body 55 that is provided on the shaft portion 44 and operates integrally with the shaft portion 44, and the through hole 51a as a valve seat that is opened and closed by the variable throttle valve body 55. Consists of

The first valve body 51 is configured to be axially engageable with the variable throttle valve body 55 . Specifically, the upper end face of the first valve body 51 is integrally provided with a cylindrical portion 51b in which the variable throttle valve body 55 is arranged. An engagement portion 51c is provided. The engaging portion 51c is configured to contact the variable throttle valve body 55 when the shaft portion 44 moves upward. Further, a plurality of flow paths 51d are formed in the peripheral wall of the tubular portion 51b.

The variable throttle valve body 55 is configured to be able to open and close the upper end (opening) of the through hole 51 a of the first valve body 51 . That is, the variable throttle valve body 55 abuts against the through hole 51a to close the through hole 51a when the shaft portion 44 moves downward. The opening diameter of the through hole 51 a is smaller than the opening diameter of the first valve seat 52 .

In the first valve 31 configured as described above, when the shaft portion 44 is driven upward, the upper end surface of the variable throttle valve body 55 abuts against the engaging portion 51c in the axial direction. 51 is pushed upward against the biasing force of the first biasing member 53 and separated from the first valve seat 52 (see FIG. 4(b)). On the other hand, when the shaft portion 44 is driven downward, the first valve body 51 is pushed down by the biasing force of the first biasing member 53, contacts the first valve seat 52, and pushes the opening of the first valve seat 52. It closes (see FIGS. 2 and 3(b)).

When the first valve body 51 closes the first valve seat 52, the amount of refrigerant flowing through the through hole 51a is adjusted by adjusting the axial position of the variable throttle valve body 55 in the cylindrical portion 51b. is possible (see FIG. 3(b)). This allows fine adjustment of the amount of coolant flowing through the first flow path 41 . Further, when the first valve body 51 closes the first valve seat 52, the high-pressure refrigerant flowing from the first inlet 41a is depressurized through the through-hole 51a, becomes a low-pressure refrigerant, and becomes the first outlet. It flows to the 1st heat exchange part 21 side from 41b. Note that when both the first valve seat 52 and the through hole 51a are closed, the first flow path 41 is closed (the opening area of the first flow path 41 becomes zero).

As shown in FIGS. 2 and 4B, the second valve 32 has a second valve body 61 and a second valve seat 62 fixed to the housing 30 . Also, the third valve 33 includes a third valve body 71 and a third valve seat 72 provided in the housing 30 .

The second and third valve bodies 61 and 71 are provided integrally with one valve body member 80 . The valve body member 80 is disposed between the second valve seat 62 and the third valve seat 72 that face each other in the axial direction of the shaft portion 44 and is configured to be axially engageable with the shaft portion 44 . The third valve seat 72 is arranged below the second valve seat 62 . The second valve body 61 is provided on the upper end face of the valve body member 80, and the third valve body 71 is provided on the lower end face of the valve body member 80, respectively. Further, the valve body member 80 is axially biased toward the third valve seat 72 by a second biasing member 81 (compression coil spring). The valve body member 80 having the second valve body 61 and the third valve body 71 and the second and third valve seats 62 and 72 form a three-way valve. The biasing force of the first biasing member 53 to the first valve body 51 is set larger than the biasing force of the second biasing member 81 to the valve body member 80 .

As shown in FIG. 4B, when the shaft portion 44 is driven upward, the valve body member 80 is positioned below the valve body member 80 and protrudes from the outer peripheral surface of the shaft portion 44. Due to the engagement with the portion 82 , the third valve body 71 of the valve body member 80 is pushed upward against the biasing force of the second biasing member 81 and separated from the third valve seat 72 . Thereafter, when the valve body member 80 is further pushed upward, the second valve body 61 of the valve body member 80 comes into contact with the second valve seat 62 to close the opening of the second valve seat 62 .

On the other hand, as shown in FIG. 2, when the shaft portion 44 is driven downward, the valve body member 80 is pushed down by the biasing force of the second biasing member 81 and comes into contact with the third valve seat 72. The opening of the valve seat 72 is closed. The shaft portion 44 has a contact portion 83 that can axially contact the upper end surface of the valve body member 80 when the shaft portion 44 is driven downward.

The integrated valve ECU 27 includes a drive current control section 27a that controls drive current (motor drive current) supplied to the motor 26 . The control of the drive current controller 27a when a stepping motor capable of positioning by open loop control is used as the motor 26 will be described below. The drive current control section 27a manages the rotation angle of the motor 26 according to the number of drive pulses input to the motor 26. FIG. Then, the drive current control section 27a performs position control of the shaft section 44 based on the origin position P0 detected by the initialization process.

In the initialization process, the drive current control section 27a intentionally abuts the shaft section 44 at the end position (physical limit position) of its range of motion, and stores that position as the origin position P0 (zero position). Note that the origin position P0 in this embodiment is the lower end position of the range of motion of the shaft portion 44, and the position of the shaft portion 44 with respect to the upper end surface of the valve body member 80 that closes the opening of the third valve seat 72. This is the position where the contact portion 83 abuts (see FIG. 2).

Further, the drive current control unit 27a adjusts the rotation speed of the motor 26 by changing the frequency of the motor drive current. Specifically, the drive current control unit 27a adjusts the motor drive current by PWM control, and adjusts the rotational speed of the motor 26 by changing the control frequency (PWM frequency) of the PWM control. That is, by increasing the control frequency of the PWM control, the number of revolutions of the motor 26 is increased, and by decreasing the control frequency of the PWM control, the number of revolutions of the motor 26 is controlled to be small.

Further, the drive current control section 27a adjusts the current value of the motor drive current. Methods for varying the current value of the motor drive current in the drive current control unit 27a include a method for varying the reference current without changing the duty ratio of PWM control, a method for varying the duty ratio itself, and the like. Further, the drive current control unit 27a controls the command value of the rotation speed (frequency of the drive current) and the command value of the current value of the motor 26 according to the axial position of the shaft part 44 based on a preset map or calculation formula. set the value.

The first pressure sensor 28 is provided in the flow path on the upstream side (first inlet 41a side) of the first valve 31 , detects the pressure on the upstream side, and outputs the information to the integrated valve ECU 27 . The second pressure sensor 29 is provided in the flow path on the downstream side (first outflow port 41b side) of the first valve 31 , detects the pressure on the downstream side, and outputs the information to the integrated valve ECU 27 .

Behaviors of the refrigeration cycle device D and the integrated valve device 24 during the heating mode are shown in FIGS. FIG. 5 is a graph showing the opening area (cross-sectional area) of each of the first to third flow paths 41 to 43 according to the axial position (number of pulses) of the shaft portion 44. The opening area of the channel 41 is indicated by a solid line, the opening area of the second channel 42 is indicated by a broken line, and the opening area of the third channel 43 is indicated by a dashed line.

In the heating mode, the shaft portion 44 is located on the zero position side (lower side) than the position P1 (the position where the first valve body 51 separates from the first valve seat 52) where the opening operation of the first valve body 51 is started. do. That is, in the heating mode, the first valve 31 (first valve seat 52 ) is closed, and the flow rate of refrigerant in the first flow path 41 is adjusted by the variable throttle valve 54 . At this time, the high-pressure refrigerant compressed by the compressor 11 and supplied to the first inlet 41a through the water-cooled condenser 12 (first heat exchange portion 12a) is decompressed through the through hole 51a of the variable throttle valve 54, It becomes a refrigerant and flows from the first outflow port 41b to the first heat exchanging part 21 side. Also, at this time, the third valve 33 is closed and the second valve 32 is opened.

The refrigerant that has flowed into the first heat exchanging portion 21 from the first outflow port 41b of the integrated valve device 24 through the inflow passage 21a passes through the inside of the first heat exchanging portion 21, and then flows through the outflow passage 21b into the integrated valve. It flows into the second inlet 42 a of the device 24 . At this time, since the third flow path 43 (the third valve 33) is closed and the second flow path 42 (the second valve 32) is opened, the refrigerant flowing from the second inlet 42a is It is discharged from the second outlet 42 b of the second flow path 42 . The refrigerant discharged from the second outlet 42b is sucked into the compressor 11, compressed again, and discharged to the water-cooled condenser 12 side.

When switching from the heating mode to the cooling mode, the motor 26 is driven to drive the shaft portion 44 upward. At this time, after the first valve 31 is opened at position P1, the third valve 33 (third flow path 43) is opened at position P2, and then the second valve 32 ( The second flow path 42) is closed.

Behaviors of the refrigeration cycle device D and the integrated valve device 24 during the cooling mode are shown in FIGS.
In the cooling mode, the first valve 31 (first valve seat 52) is opened. Also, the third valve 33 (the third flow path 43) is opened, and the second valve 32 (the second flow path 42) is closed.

The high-pressure gas-phase refrigerant that is compressed by the compressor 11 and flows into the first inlet 41a passes through the opening of the first valve seat 52 and flows directly into the first heat exchange section 21 through the first outlet 41b without being decompressed. do. In the cooling mode, the first heat exchange section 21 functions as a condenser. That is, the refrigerant passing through the first heat exchange section 21 exchanges heat with the outside air, and part of it changes to a liquid phase.

After passing through the first heat exchange section 21, the refrigerant that has flowed into the second inlet 42a through the outlet channel 21b passes through the third channel 43 and is discharged from the third outlet 43b. The refrigerant discharged from the third outlet 43b flows into the second heat exchange section 22 via the reservoir 23 and the inflow passage 22a. After passing through the second heat exchange section 22 , the refrigerant discharged from the second heat exchange section 22 is supplied to the evaporator 14 via the expansion valve 13 . After heat exchange in the evaporator 14 (cooling of blown air), the refrigerant flows out toward the compressor 11 and is compressed again in the compressor 11 .

When the cooling mode is switched to the heating mode, the motor 26 is driven to drive the shaft portion 44 downward from the upper limit position P3. At this time, after the second valve 32 (second flow path 42) is opened, the third valve 33 (third flow path 43) is closed at position P2, and then the first valve seat 52 is closed at position P1. It is closed by the valve body 51 .

Here, a control mode of the integrated valve ECU 27 when switching from the cooling mode to the heating mode (that is, when the shaft portion 44 is driven downward) will be described.
As shown in FIGS. 6(a) and 6(b), when the driving current control unit 27a of the integrated valve ECU 27 receives the command to start the motor 26, the rotation speed (the frequency of the driving current) of the motor 26 is set to the first rotation speed. r1, and the current value of the motor drive current is a first value A1. At this time, the drive current control unit 27a increases the rotation speed of the motor 26 stepwise to the first rotation speed r1.

Thereafter, before the shaft portion 44 passes through the position P1 where the first valve seat 52 is closed by the first valve body 51, the drive current control portion 27a controls the rotation speed of the motor 26 to reach the first rotation speed. It is decreased from r1 to a second rotation speed r2, and is kept constant at the second rotation speed r2 until after the shaft portion 44 has passed the position P1. Further, the drive current control unit 27a increases the current value of the motor drive current from the first value A1 to the second value A2 before the shaft portion 44 passes the position P1, and the shaft portion 44 passes the position P1. The second value A2 is kept constant until after the As a result, the motor 26 is driven with high torque when the shaft portion 44 passes through the position P1. After the shaft portion 44 passes through the position P1, the drive current control section 27a returns the rotation speed of the motor 26 to the first rotation speed r1, and returns the motor drive current to the first value A1.

Next, the control mode of the drive current control section 27a in the initialization process will be described with reference to FIGS. 7(a) and 7(b). Since the motor 26 as a stepping motor tends to cause an error in position accuracy (that is, the origin position P0 tends to shift), the drive current control unit 27a executes the above-described initialization process at a predetermined timing (for example, (executes each time the vehicle ignition is turned on). FIG. 7 shows a case in which the stored origin position P0 is displaced above the position of the end of the actual range of motion (impact position). Of course, it is possible that P0 may deviate below the position of the end of the actual range of motion (impact position). In the initialization process, the drive current control section 27a drives the motor 26 by two-phase excitation.

As shown in FIGS. 7A and 7B, in the initialization process of this embodiment, the shaft portion 44 is driven downward. At this time, the drive current control section 27a operates in the same manner as when switching from the cooling mode to the heating mode until the shaft section 44 reaches the set position P4 set between the position P1 and the origin position P0. It controls the rotation speed of the motor 26 and the motor drive current. That is, in the initialization process, when the section until the shaft portion 44 reaches the set position P4 is the first section S1, the rotation speed of the motor 26 in the first section S1 is the first rotation speed r1 or the second rotation speed r1. The number of revolutions is r2. Also, the set position P4 is set at a position before the shaft portion 44 hits the lower end of the movable range in consideration of the error of the origin position P0 that may occur during normal use of the motor 26 .

When the shaft portion 44 reaches the set position P4, the drive current control portion 27a increases the rotation speed of the motor 26 from the first rotation speed r1 to the third rotation speed r3 stepwise (for example, linearly). Let That is, in the downward drive of the shaft portion 44 in the initialization process, when the section from the set position P4 to the origin position P0 side is the second section S2, the rotation speed of the motor 26 in the second section S2 is the same as that in the first section S1. is set to a third rotation speed r3 that is greater than the rotation speed (first rotation speed r1) at .

Then, in the second section S2, the drive current control unit 27a controls a predetermined number of pulses below the origin position P0 (the minus side when the upper side with respect to the origin position P0 is the plus side) (hereinafter referred to as the number of stop pulses). ), the motor 26 is driven at the third rotation speed r3. The number of stop pulses is determined by taking into consideration the error of the origin position P0 that may occur during normal use of the motor 26. is set to a number of pulses long enough for As a result, the shaft portion 44 hits the lower end of the movable range in a state where the rotation speed of the motor 26 is set to the third rotation speed r3, and the motor 26 is out of step at that position. Then, when the number of stop pulses is reached and the power supply to the motor 26 is turned off, the drive current control section 27a resets the origin position P0 (that is, updates the origin position P0). In this way, in the initialization process, by increasing the number of rotations of the motor 26 to the third number of rotations r3 at the set position P4 before reaching the origin position P0, the shaft portion 44 can be brought into contact with the lower end of the movable range. Rotational torque (pullout torque) can be reduced. As a result, the load applied to the shaft portion 44 and the other side at the time of striking can be reduced. In this embodiment, even when the shaft portion 44 reaches the set position P4, the drive current control section 27a keeps the motor drive current constant at the first value A1 (see FIG. 7A).

In the initialization process, the motor 26 is energized for a while even after the shaft portion 44 hits the lower end of the movable range. During this energization, pull-in torque (pull-in torque) is repeatedly generated in the motor 26 with the shaft portion 44 in contact with the lower end of the movable range (or with a slight gap), and the repeatedly generated pull-in torque , the shaft portion 44 operates (vibrates) so as to apply a load to the lower end portion of the movable range. However, since the rotation speed of the motor 26 at this time is the third rotation speed r3, which is higher than the normal speed (the first rotation speed r1), the pull-in torque can be suppressed low. The pull-in torque can reduce the load applied to the shaft portion 44 and the other side.

As shown in FIG. 8, the third rotation speed r3 is equal to or higher than the maximum self-starting frequency ra, which is the drive frequency at which the pull-in torque becomes zero, and the maximum response frequency rb, which is the drive frequency at which the pull-out torque becomes zero. It is desirable to set the following. The maximum self-starting frequency ra is the maximum frequency at which starting, forward rotation, and reverse rotation can be controlled in synchronization with the input driving pulse. This is the maximum frequency at which the motor 26 will continue to rotate in synchronism as the frequency of the pulses is increased. According to this, the pull-in torque of the motor 26 after the shaft portion 44 hits the lower end of the movable range can be made substantially zero, which is more preferable in terms of reducing the load applied to the shaft portion 44 and the other side. be.

Effects of the present embodiment will be described.
(1) The integrated valve ECU 27 performs an initialization process for updating the origin position P0 by moving the shaft portion 44 to the origin position P0 side and hitting the end of the movable range. In the initialization process, the integrated valve ECU 27 defines a section up to a set position P4 set before the origin position P0 as a first section S1, and a section from the set position P4 to the origin position P0 as a second section S2. The rotational torque of the motor 26 in the second section S2 is made lower than the rotational torque of the motor 26 in the first section S1. According to this aspect, when the shaft portion 44 is driven downward in the initialization process, the rotational torque of the motor 26 is reduced in the second section S2 on the origin position P0 side from the set position P4. As a result, the load applied when the shaft portion 44 hits the end portion of the movable range in the initialization process can be reduced.

(2) In the initialization process executed by the integrated valve ECU 27, the number of rotations of the motor 26 in the second section S2 (that is, the third number of rotations r3) is changed to the number of rotations of the motor 26 in the first section S1 (that is, the first is greater than the number of revolutions r1). As a result, in the initialization process, the rotational torque of the motor 26 in the second section S2 can be made lower than the rotational torque of the motor 26 in the first section S1.

(3) The motor 26 is a stepping motor, and the rotation speed (third rotation speed r3) of the motor 26 in the second section S2 is set to be equal to or higher than the maximum self-starting frequency ra of the motor 26 and equal to or lower than the maximum response frequency rb. It is As a result, the pull-in torque of the motor 26 after the shaft portion 44 hits the lower end of the movable range can be made substantially zero. ) can be more suitably reduced.

This embodiment can be implemented with the following modifications. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
In the initialization process of the above embodiment, when the shaft portion 44 enters the second section S2, the rotation speed of the motor 26 is increased to the third rotation speed r3, while the current value of the motor drive current is increased to the first section S1. is set to the first value A1 without change. However, other than this, for example, as shown in FIGS. 9A and 9B, the current value of the motor drive current in the second section S2 is set lower than the current value (first value A1) in the first section S1. In addition, the number of revolutions of the motor 26 in the second section S2 may be kept constant at the first number of revolutions r1. In the example shown in FIG. 9A, when the shaft portion 44 reaches the set position P4, the drive current control portion 27a changes the current value of the motor drive current stepwise from the first value A1 to the third value A3. Decrease (eg, linearly).

According to the control modes shown in FIGS. 9A and 9B, the current value of the motor drive current in the second section S2 is made lower than the current value in the first section S1. Even without changing the rotational speed of the motor 26, the rotational torque of the motor 26 in the second section S2 can be made lower than the rotational torque of the motor 26 in the first section S1.

In the above embodiment and the example shown in FIG. 9, only one of the number of revolutions of the motor 26 and the current value of the motor drive current is changed in the second section S2. It is also possible to change both the rotation speed of the motor 26 and the current value of the motor drive current (that is, increase the rotation speed of the motor 26 and decrease the current value of the motor drive current).

In the above embodiment, the motor 26 is driven by non-microstep excitation such as two-phase excitation over the first section S1 and the second section S2. As shown in b), the excitation method of the motor 26 in the first interval S1 may be non-microstep excitation such as two-phase excitation, and the excitation method of the motor 26 in the second interval S2 may be microstep excitation. By setting the excitation method of the motor 26 to microstep excitation, the current value of the motor drive current is reduced. Therefore, as shown in FIG. It can be made smaller than the current value (first value A1) of the motor drive current in S1. This aspect also allows the rotational torque of the motor 26 in the second section S2 to be lower than the rotational torque of the motor 26 in the first section S1.

In the above embodiment, in the initialization process, after the shaft portion 44 has passed the position P1 where the first valve seat 52 is closed by the first valve body 51, the rotation speed of the motor 26 is changed from the second rotation speed r2 to the second rotation speed r2. The rotation speed is once increased to the first rotation speed r1, and then increased from the first rotation speed r1 to the third rotation speed r3 when the shaft portion 44 reaches the set position P4. However, in addition to this, for example, as shown in FIG. 11, the set position P4 is set at a position where the rotation speed of the motor 26 is lowered to the second rotation speed r2 corresponding to the passage of the position P1, and the shaft portion 44 reaches the set position P4, the rotation speed of the motor 26 may be increased from the second rotation speed r2 to the third rotation speed r3. It should be noted that when the shaft portion 44 is driven downward in the normal drive that is not the initialization process (that is, when switching from the cooling mode to the heating mode), the rotation speed is similarly reduced from the second rotation speed r2 to the third rotation speed r2 as shown in FIG. A control mode may be adopted in which the rotational speed is increased to r3.

In the above embodiment, the abutting position when the shaft portion 44 is driven downward (that is, driven away from the motor 26) is the origin position P0. It is also possible to adopt a mode in which the abutment position when the driving direction is driven is the origin position P0.

During the initialization process of the above embodiment and during switching from the cooling mode to the heating mode, the rotational torque of the motor 26 is increased (that is, the rotational speed of the motor 26 is set to the second rotational speed r2, and the current value is The current is controlled so that the first valve seat 52 passes through the position P1 where the first valve body 51 is closed in the second value A2. However, the present invention is not limited to this, and current control is performed so that the rotation speed of the motor 26 is set to the first rotation speed r1, the current value is set to the first value A1, and the rotation torque is not changed so that the shaft portion 44 passes through the position P1. You may

- It is also possible to use a brushless synchronous motor, a motor with a brush, etc. as the motor 26 other than a stepping motor. In the case of a motor with a brush, the rotation speed of the motor can be adjusted by changing the voltage applied to the motor.

In the above embodiment, the function of the drive current control section 27a is provided in the integrated valve ECU 27 provided integrally with the integrated valve device 24, but the present invention is not limited to this. It may be provided in an ECU (such as an air conditioner ECU).

The configuration of the opening/closing mechanism of the plurality of valves (first to third valves 31 to 33) in the integrated valve device 24 of the above embodiment is an example, and other than the above embodiment may be used depending on the configuration of the refrigeration cycle device D, etc. configuration can be changed.

D... Refrigeration cycle device, 10... Heat exchanger, 24... Integrated valve device, 25... Valve body, 26... Motor, 27... Integrated valve ECU (motor control device), 31... First valve, 32... Second valve , 33 ... third valve, 44 ... shaft, P4 ... set position, S1 ... first section, S2 ... second section.

Claims (5)

A valve body comprising a single motor, a shaft portion that moves in its own axial direction based on the drive of the motor, and a plurality of valves that are opened and closed by engagement with the shaft portion in the axial direction. It controls the motor of the integrated valve device, stores the position where the shaft hits the end of the movable range as an origin position, and grasps the position of the shaft with reference to the origin position. A motor control device for controlling
In the initialization process for updating the origin position by moving the shaft portion toward the origin position and abutting against the end of the range of motion, a section up to a set position set before the origin position is set to a first position. and a section on the origin position side from the set position is defined as a second section, and the rotational torque of the motor in the second section is made lower than the rotational torque of the motor in the first section ,
A motor control device that makes the number of rotations of the motor in the second section higher than the number of rotations of the motor in the first section . the motor is a stepping motor,
2. The motor control device according to claim 1 , wherein the number of revolutions of said motor in said second interval is set to be equal to or higher than a maximum self-starting frequency of said motor and equal to or lower than a maximum response frequency. 3. The motor control device according to claim 1, wherein a current value of drive current supplied to said motor is lower in said second section than in said first section. An integrated valve device provided in a refrigeration cycle device for a vehicle,
a valve body having a motor, a shaft portion that moves in its own axial direction based on the drive of the motor , and a plurality of valves that are opened and closed by engagement with the shaft portion in the axial direction; and the motor control device according to any one of the above. A heat exchanger that constitutes a part of a refrigeration cycle device for a vehicle, and is characterized by being integrally provided with the integrated valve device according to claim 4 .

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