JP2019146361A - Drive controller for servo motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adaptively control a servomotor while suppressing a cost. SOLUTION: An auto air conditioner ECU 30 performs drive control for a servomotor 21 for driving a blowout mode door provided in the auto air conditioner 1 and driven by a battery. Specifically, the auto air conditioner ECU 30 detects the rotation position of the blowout mode door drive servomotor 21, and when the detected rotation position falls within the designated range including the target position, the blowout mode door drive servomotor 21 is operated. Stop it. The auto air conditioner ECU 30 also changes the width of the designated range according to the vehicle state (voltage value of the battery and air volume of the blower 4). [Selection diagram] Fig. 1

Description

  The present invention relates to a servo motor drive control device, and more particularly to a servo motor drive control device that performs drive control for a servo motor driven by a DC voltage.

  According to Patent Document 1, the current rotational position of the DC servo motor is constantly monitored by a potentiometer. When the rotational position approaches the equivalent value of the target position, the drive of the DC servo motor is switched from DC drive to PWM drive by the CPU. As a result, hunting due to inertia of the DC servo motor can be prevented.

JP-A-8-182366

  However, in Patent Document 1, it is necessary to add a special circuit such as a PWM control circuit, which causes a problem of increasing the cost of the entire system. When a control device such as that disclosed in Patent Document 1 is mounted on a vehicle, the amount of inertia of the servo motor varies depending on the vehicle state such as variation in the power supply voltage value and blower air volume of the air conditioner. However, Patent Document 1 has a problem that adaptive control cannot be performed because the vehicle state as described above is not taken into consideration.

  Therefore, a main object of the present invention is to provide a drive control device for a servo motor that can adaptively control the servo motor while suppressing cost.

  A drive control device for a servo motor according to the present invention is a drive control device that performs drive control on a servo motor that is provided in an in-vehicle device and is driven by a battery, and a detection unit that detects a rotational position of the servo motor, A stopping means for stopping the rotation of the servo motor when the rotational position detected by the detecting means enters a designated range including the target position, and a changing means for changing the width of the designated range according to the vehicle state.

  Preferably, the vehicle-mounted device is an air conditioner, and the vehicle state is a battery voltage value and / or a blower air volume.

  The rotation of the servo motor is stopped when the rotation position enters the specified range including the target position, and the width of the specified range is changed based on the change in the inertia amount of the servo motor according to the vehicle state . As a result, it is possible to avoid as much as possible the reduction in stop position accuracy due to the specified range being too wide and the occurrence of hunting due to the specified range being too narrow. That is, adaptive control of the servo motor according to the vehicle state is realized. In addition, since a special circuit such as a PWM control circuit is unnecessary, cost can be reduced.

  The above object, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an embodiment of a vehicle air-conditioning control apparatus according to the present invention. It is a graph which shows an example of the relationship between the rotation position of the blowing mode door drive servomotor and the blowing mode. It is a flowchart which shows a part of operation | movement of auto air-conditioner ECU. It is a graph which shows an example of the drive characteristic of the servomotor for blowing mode doors. It is a flowchart which shows a part of other operation | movement of auto air-conditioner ECU. (A) is a graph which shows an example of the relationship between a battery voltage and a voltage hysteresis setting value, (B) is a graph which shows an example of the relationship between a blower air volume and a blower setting value.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the schematic configuration diagram of FIG. However, the present invention is not limited or limited to the following description.

  As shown in FIG. 1, an auto air conditioner (air conditioner) 1 according to the present embodiment is an air conditioner mounted on a vehicle, and an auto air conditioner ECU (Electronic Control) described in detail later in a duct 2 that sends air into the vehicle interior. A blower (blower) 4 driven by a blower motor 3 controlled by a unit (30), an evaporator (cooling heat exchanger) 5, an air mix door 6, and a heater core (heating heat exchanger) 7 are upstream of the air flow path. Are arranged sequentially.

  On the inlet side of the duct 2 upstream of the blower 4, an inside air introduction port 9 and an outside air introduction port 10 that are air introduction ports are formed. Based on an operation by a vehicle occupant of an inside / outside air changeover switch provided in the auto air conditioner ECU 30, The inside / outside air switching door 12 provided inside the both inlets 9 and 10 is driven by the inside / outside air switching door drive servo motor 11 controlled by the automatic air conditioner ECU 30, and one of the both inlets 9 and 10 is driven. Is opened and the other is closed, so that the inside air or outside air is introduced into the duct 2.

  The evaporator (cooling heat exchanger) 5 is disposed on the downstream side of the blower 4 in the middle of the refrigeration cycle, and is turned on by a vehicle occupant of an air conditioner power switch (hereinafter referred to as an air conditioner switch) provided in the auto air conditioner ECU 30. A compressor (not shown) is connected to the engine and is driven by the rotation of the engine to compress the refrigerant, and the high-temperature and high-pressure refrigerant is radiated by a capacitor (not shown) and radiated into the evaporator 5 via an expansion valve (not shown). As the refrigerant flows and vaporizes, the air that passes through the evaporator 5 and flows in the duct 2 is heat-exchanged and cooled. A post-evaporation temperature sensor 13 for detecting the temperature of the evaporator fin is disposed downstream of the evaporator 5, and a detection signal of the post-evaporation temperature sensor 13 is taken into the auto air conditioner ECU 30.

  The heater core (heating heat exchanger) 7 is disposed downstream of the evaporator 5 so as to block a part of the duct 2, and the engine coolant flows through the pipe through the heater core 7. The inside air or the outside air is heated by passing through the heater core 7. At this time, the air mix door 6 provided at the air inlet of the heater core 7 is driven by the air mix door driving servo motor 8 controlled by the auto air conditioner ECU 30, and the air mix door 6 is controlled to open and close. The opening degree of the ventilation inlet is adjusted, whereby the heating temperature of the inside air or the outside air by the heater core 7 is controlled. The opening degree of the air mix door 6 is taken into the automatic air conditioner ECU 30 as a detection signal of the air mix door opening degree detection means 14.

  Here, the state in which the air inlet of the heater core 7 is completely closed by the air mix door 6 is a so-called MAX cool (opening degree 0%) control state, and the heater core 7 in the duct 2 is opened by opening the air inlet of the heater core 7. The state in which the passage not provided is fully closed by the air mix door 6 (the vent inlet is fully open) is a so-called MAX hot (opening degree 100%) control state, and the air mix door 6 is controlled to the cool side. When the air mix door 6 is controlled to the hot side, the air that has passed through the evaporator 5 is heated by the heater core 7 and then flows downstream.

  A defroster air outlet 15, a face air outlet 16, and a foot air outlet 17 are formed in the most downstream portion of the duct 2. A defroster opening / closing door 18, a face opening / closing door 19, and a foot opening / closing door 20 are rotatably arranged upstream of the air outlets 15, 16, 17. These blowing mode doors 18, 19, and 20 are opened and closed by a common blowing mode door driving servomotor 21 controlled by the automatic air conditioner ECU 30 via a link mechanism.

  In the present embodiment, the blowing mode is switched as shown in FIG. 2 by variably controlling the rotational position (door opening) of the blowing mode door drive servomotor 21. According to FIG. 2, when the rotational position or the door opening degree is changed from 0% to 100%, the blowing mode is changed to the face mode → bilevel mode → foot mode → foot defroster mode (also referred to as foot differential mode) → It is switched in the order of defroster mode.

  The blowing mode door opening degree detection means 22 detects the door opening degree. Since the relationship between the door opening degree and the blowing mode is as described above, it is possible to determine which is the blowing mode at a certain point based on the door opening degree.

  Here, the face mode is a mode in which the face air outlet 16 is opened by the face opening / closing door 19 and the conditioned air is blown out only from the face air outlet 16 toward the upper body of the passenger.

  In the bi-level mode, both the face air outlet 16 and the foot air outlet 17 are simultaneously opened by the face opening / closing door 19 and the foot opening / closing door 20, and the face air outlet 16 and the foot air outlet are directed toward the upper body of the occupant and the feet of the occupant. 17 is a mode in which conditioned air is blown from both.

  The foot mode is a mode in which the foot air outlet 17 is opened by the foot opening / closing door 20 and the conditioned air is blown out only from the foot air outlet 17 toward the feet of the occupant.

  In the foot differential mode, both the foot outlet 17 and the defroster outlet 15 are simultaneously opened by the foot opening / closing door 20 and the defroster opening / closing door 18, and the foot outlet 17 and the defroster outlet 15 are directed toward the feet of the passenger and the Freund glass. It is the mode which blows off the conditioned air from both.

  The defroster mode is a mode in which the defroster air outlet 15 is opened by the defroster opening / closing door 18 and the conditioned air is blown out from the defroster air outlet 15 toward the windshield F.

  The automatic air conditioner ECU 30 serving as a drive control device includes a known microcomputer configuration and its peripheral circuits. The auto air conditioner ECU 30 stores a control program for air conditioning control, and performs various calculations and processes based on the control program. The auto air conditioner ECU 30 receives sensor detection signals from various sensors, and receives various operation signals from an air conditioner panel 31 disposed in the vicinity of the instrument panel in the front part of the vehicle interior.

  As the sensors, there are provided a voltage sensor 26 for detecting the voltage of the battery, a blower sensor 27 for detecting the air volume of the blower 4, an outside air temperature sensor 28 for detecting the outside temperature of the passenger compartment, an inside air temperature sensor 29 for detecting the inside temperature of the passenger compartment, and the like. It is also preferable to arrange a temperature and humidity sensor for detecting the temperature and relative humidity of the windshield F in the vicinity of the room mirror on the inner surface of the windshield F.

  The voltage sensor 26 may be one that detects the battery voltage as a digital value, or one that detects an analog value. Further, with respect to the air volume of the blower 4, instead of the blower sensor 27 that detects the air volume, "blower air volume determining means" that determines the air volume based on various sensor values may be provided.

  The air conditioner panel 31 includes an air conditioner switch (air conditioner power switch) for driving / stopping the air conditioner, and a mode selection switch (air conditioner operation mode selection) for selecting either an automatic control mode or a manual control mode as an air conditioner operation mode. Switch), a blowing mode switching switch for switching the blowing mode, an inside / outside air switching switch for manually switching the inside / outside air switching door 12, and a dedicated air outlet for blowing the conditioned air toward the windshield F only from the defroster outlet 15. A differential mode switch, a temperature setting switch for setting the air conditioning temperature, an air volume switch for switching the intensity of air flow, and the like are arranged.

  The air-conditioning door drive servo motor 8, the inside / outside air switching door drive servo motor 11, the blowout mode door drive servo motor 21, etc. are connected to the output side of the auto air conditioner ECU 30. It is controlled by the output signal of the air conditioner ECU 30.

  The outline of the operation of the auto air conditioner 1 is as follows. By operating the blower 4, air introduced from the inside air introduction port 9 or the outside air introduction port 10 is blown through the duct 2 toward the vehicle interior. The air blown from the blower 4 is first cooled and dehumidified through the evaporator 5, and this cold air is then arranged in the flow through the heater core 7 according to the rotation position (door opening) of the air mix door 6 and the heater core 7. It is divided into a flow that passes through a passage that is not provided. The flow passing through the heater core 7 is heated to become warm air, and the flow passing through the passage where the heater core 7 is not disposed remains cold air.

  Therefore, the ratio of the amount of air passing through the heater core 7 (warm air amount) and the amount of air passing through the passage where the heater core 7 is not disposed (cold air amount) is adjusted according to the opening of the air mix door 6. The temperature of the air blown into the room can be adjusted. Then, the temperature-controlled conditioned air is supplied from any one or more of the defroster air outlet 15, the face air outlet 16 and the foot air outlet 17 located at the most downstream portion of the air passage of the duct 2. It blows out into the passenger compartment, and air conditioning in the passenger compartment and fogging prevention of the windshield F of the vehicle are performed.

  When performing drive control for the blowout mode door drive servomotor 21, the automatic air conditioner ECU 30 executes processing according to the flowchart shown in FIG. A control program corresponding to this flowchart is stored in a memory (not shown).

  In step S01, it is repeatedly determined whether or not the blow mode door drive servomotor 21 should be started based on the operation of the blow mode switch or the differential mode switch. When the determination result is updated from NO to YES, the process proceeds to step S02. In step S02, the rotation direction and target position of the blow mode door drive servomotor 21 are determined based on the current rotation position of the blow mode door drive servo motor 21 and the operation mode of the blow mode switch or differential mode switch. To do. In step S03, the blowing mode door drive servomotor 21 is rotated in the rotation direction determined in step S02.

  In step S04, the current rotational position of the blowing mode door drive servomotor 21 is detected based on the output of the blowing mode door opening degree detection means 22. In step S05, it is determined whether or not the detected rotational position has entered a designated range (target range ± a range) including the target position determined in step S02. If a determination result is NO, it will return to Step S04. On the other hand, if a determination result is YES, it will progress to step S06 and will stop rotation of the servomotor 21 for blowing mode door drive. When the process of step S06 is completed, the process returns to step S01.

  The drive characteristics of the blowout mode door drive servomotor 21 are shown in FIG. According to FIG. 4, a subtracted value obtained by subtracting the current rotational position from the target position is assigned to the horizontal axis. The blowout mode door drive servomotor 21 is driven to the defroster mode side when the target position is determined so that the subtraction value shows a value of “b” or more, and the subtraction value becomes a value of “−b” or less. As shown, when the target position is determined, the face mode is driven. The blowout mode door drive servomotor 21 is also stopped when the absolute value of the subtraction value drops to “a”.

  “A” can be defined as a set hysteresis value at stop, and “b” can be defined as a set hysteresis value during driving. In addition, a relationship of b> a is established between the two.

  Ideally, the rotation of the blowout mode door drive servomotor 21 stops at the target position. However, in practice, the stop position deviates from the target position due to the inertia of the blow mode door drive servomotor 21. The above-mentioned “a” is set in consideration of such a shift of the stop position.

  However, if the value of “a” is too large, the accuracy of the stop position decreases. Conversely, if the value of “a” is too small, hunting occurs. On the other hand, the inertial amount of the blowout mode door drive servomotor 21 varies according to vehicle conditions such as battery voltage variation and the airflow of the blower 4 (the reason why the inertial amount varies depending on the airflow of the blower 4 is from the blower 4 Because the wind hinders the door opening and closing action). Therefore, in this embodiment, the value of “a” is adjusted according to the vehicle state.

  Specifically, processing according to the flowchart shown in FIG. 5 is executed under the control of the auto air conditioner ECU 30. A control program corresponding to this flowchart is also stored in a memory (not shown). Data corresponding to the graphs shown in FIGS. 6A and 6B is also stored in the memory.

  FIG. 6A is a graph showing a change in the voltage hysteresis set value with respect to the battery voltage, and FIG. 6B is a graph showing a change in the blower hysteresis set value with respect to the air volume of the blower 4. According to FIG. 6A, it is assumed that the battery voltage changes in the range of 9V to 16V, and the voltage hiss setting value increases from “a−2” to “a” as the battery voltage increases. According to FIG. 6B, it is assumed that the air volume of the blower 4 changes in the range of level 1 to level 31, and the blower set value increases from “a−2” to “a” as the air volume increases. To do.

  Returning to FIG. 5, in step S11, the battery voltage is detected, and in step S12, the voltage hysteresis set value is specified with reference to the graph shown in FIG. In step S13, the air volume of the blower 4 is detected, and in step S14, the blower set value is specified with reference to the graph shown in FIG. In step S15, the larger one of the voltage hysteresis setting value and the blower hysteresis setting value thus identified is determined as the stop hysteresis setting value “a”.

  As can be seen from the above description, the auto air conditioner ECU 30 performs drive control for the blow mode door drive servomotor 21 provided in the auto air conditioner 1 and driven by a battery. Specifically, the automatic air conditioner ECU 30 detects the rotational position of the blowout mode door drive servomotor 21 (S04), and when the detected rotational position falls within a specified range including the target position, the blowout mode door drive servo The motor 21 is stopped (S05, S06). The auto air conditioner ECU 30 also changes the width of the designated range according to the vehicle state (battery voltage value and air flow rate of the blower 4) (S11 to S15).

  The rotation of the blowout mode door drive servomotor 21 is stopped when the rotation position enters the designated range including the target position. The width of the designated range depends on the vehicle state. It will be changed based on the change in 21 inertial amounts. As a result, it is possible to avoid as much as possible the reduction in stop position accuracy due to the specified range being too wide and the occurrence of hunting due to the specified range being too narrow. That is, adaptive control of the blowout mode door drive servomotor 21 according to the vehicle state is realized. In addition, since a special circuit such as a PWM control circuit is unnecessary, cost can be reduced.

  In this embodiment, the width of the designated range is changed based on both the battery voltage value and the air flow rate of the blower 4. However, based on either the battery voltage value or the air flow rate of the blower 4. The width of the designated range may be changed.

  In this embodiment, the drive control for the blowout mode door drive servomotor 21 has been described. However, the drive control of the present invention includes the air mix door drive servomotor 8 and the inside / outside air switching door drive servomotor. 11 may be performed.

DESCRIPTION OF SYMBOLS 1 ... Auto air conditioner 3 ... Blower motor 4 ... Blower 5 ... Evaporator (heat exchanger for cooling)
7 ... Heater core (heat exchanger for heating)
DESCRIPTION OF SYMBOLS 15 ... Defroster blower outlet 16 ... Face blower outlet 17 ... Foot blower outlet 21 ... Servomotor for blowout mode door drive 22 ... Blowout mode door opening detection means 30 ... Auto air-conditioner ECU (air volume control means, air-conditioning control apparatus)

Claims (2)

A drive control device that performs drive control for a servo motor provided in an in-vehicle device and driven by a battery,
Detecting means for detecting the rotational position of the servo motor;
Stop means for stopping rotation of the servo motor when the rotational position detected by the detection means enters a designated range including a target position, and changing means for changing the width of the designated range according to a vehicle state Drive control device. The in-vehicle device is an air conditioner,
The drive control device according to claim 1, wherein the vehicle state is a voltage value and / or a blower air volume of the battery.

Images