JP2010110078A - Motor actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restore data in an operation position at a volatile storage medium even if initial setting is not performed again when applied voltage is normally restored even if applied voltage to a detecting part of a motor actuator loaded on a vehicle drops and data in the operation position is eliminated. <P>SOLUTION: The detecting part records data in the operation position of an output axis in the volatile storage medium in a non-volatile storage medium as stop position data based on turning-off of an ignition switch in the vehicle (step S370). The part records stop position data recorded in the non-volatile storage medium in the volatile storage medium as data of the operation position of the output axis, based on turning-on of the ignition switch of the vehicle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a motor actuator mounted on a vehicle.

  2. Description of the Related Art Conventionally, as a motor actuator mounted on a vehicle, one that detects an operation position of an output shaft that rotates as a motor is driven based on a change in a pulse waveform is known (for example, see Patent Document 1). In such a motor actuator, every time the operating position of the output shaft changes, the data of the operating position is recorded in a volatile storage medium such as a RAM so that the detected value of the current operating position is sequentially updated. It has become.

  However, when the ignition switch of the vehicle is turned on, an engine starter or the like operates, so that the applied voltage to the detection unit for detecting the output shaft often decreases. When the applied voltage falls below a certain level, the data on the operating position stored in the volatile storage medium may be lost.

When the operating position data disappears from the volatile storage medium, conventionally, the motor is driven to stop the operating position at a predetermined origin position, and then the data indicating the origin position is converted to the operating position data. Is recorded on a volatile storage medium (see, for example, Patent Document 1). Such an operation is called initial position setting.
JP 2004-215488 A

  However, if the initial position is set every time the ignition switch of the vehicle is turned on and the engine starter is operated, not only is the user uncomfortable, but the life of the motor actuator is shortened.

  In view of the above points, the present invention resets the initial setting when the applied voltage returns to normal even if the applied voltage to the detection unit of the motor actuator decreases and the data of the operating position is lost from the volatile storage medium. It is an object of the present invention to make it possible to restore the data of the operation position to the volatile storage medium without performing it.

  In order to achieve the above object, an invention according to claim 1 is a motor actuator mounted on a vehicle, wherein the motor (110) and an output shaft (127) rotating with the rotation of the motor (110) are provided. A pulse output unit (158) that outputs a pulse signal that changes as the output shaft (127) rotates, and a rotation angle of the output shaft (127) based on the change in the pulse signal from the pulse output unit (158). And a non-volatile storage medium (215) capable of holding stored information without receiving power supply. The detection unit (213) includes a volatile storage medium (213a) that cannot retain stored information when the voltage applied to the detection unit (213) falls below a predetermined level. .

  Further, the detection unit (213) updates the data of the operation position in the volatile storage medium (213a) according to the detected change of the operation position, and further, the vehicle ignition switch is turned off. Based on the fact that the data of the operating position in the volatile storage medium (213a) is recorded as the stop position data in the nonvolatile storage medium (215), and further, the vehicle ignition switch is turned on. The stop position data recorded in the nonvolatile storage medium (215) is recorded in the volatile storage medium (213a) as the operation position data of the output shaft (127).

  Thus, the data of the operating position of the output shaft (127) is recorded in the nonvolatile storage medium (215) when the ignition switch is turned off, and the stop in the nonvolatile storage medium (215) when the ignition switch is subsequently turned on. The position data is recorded in the RAM 213a as the operating position data of the output shaft (127).

  In this way, even if the voltage applied from the battery to the detection unit (213) drops immediately after the ignition switch is turned on and the stored content of the volatile storage medium (213a) disappears, the initial position setting is executed. Needless to say, the data of the operation position can be held again in the volatile storage medium (213a). Therefore, the frequency of initial position setting can be reduced, and the life of the motor actuator can be extended.

  In addition, as described in claim 2, the detection unit (213) is recorded in the non-volatile storage medium (215) after the ignition switch of the vehicle is turned on and before the output shaft (127) rotates. The stop position data may be recorded on the volatile storage medium (213a) as data on the operating position of the output shaft (127).

  Thus, before the output shaft (127) rotates, the stop position data recorded in the nonvolatile storage medium (215) is used as the operation position data of the output shaft (127), and the volatile storage medium (213a). As a result, the stop position data recorded in the volatile storage medium (213a) and the actual position of the output shaft (127) more reliably match.

  According to a third aspect of the present invention, when the vehicle ignition switch is turned on, the detection unit (213) detects the detection unit (213) within a predetermined time after the vehicle ignition switch is finally turned off. When the power supply to the storage device is not cut off, the stop position data recorded from the non-volatile storage medium (215) to the volatile storage medium (213a) is used as the operation position data of the output shaft (127). It may be.

  In this case, when the vehicle ignition switch is turned on, the detection unit (213) further cuts off the power supply to the detection unit (213) within a predetermined time after the vehicle ignition switch is turned off. If so, the motor (110) is controlled so as to return the output shaft (127) to the predetermined origin position, and the position data corresponding to the origin position is recorded in the volatile storage medium (213a). The position data corresponding to the origin position may be used as the operation position data of the output shaft (127).

  As described above, when the power supply to the detection unit (213) is not cut off within a predetermined time after the ignition switch is turned off, the stop position data of the nonvolatile storage medium (215) is used as the operation position of the output shaft 127. When the power supply to the detection unit (213) is cut off within a predetermined time, the initial setting is performed for the following reason.

  When the power supply to the detection unit (213) is cut off within a predetermined time after the ignition switch is turned off, the operator removes the motor actuator from the vehicle, rotates the motor for maintenance or testing purposes, and then the motor actuator There is a high possibility that it is attached to the vehicle again. In such a case, the stop position data recorded in the non-volatile storage medium (215) does not match the actual operating position of the output shaft 127. The stop position of the output shaft 127 matches.

  In addition, the code | symbol in the bracket | parenthesis in the said and the claim shows the correspondence of the term described in the claim, and the concrete thing etc. which illustrate the said term described in embodiment mentioned later. .

  Hereinafter, an embodiment of the present invention will be described. The motor actuator according to the present embodiment is used to drive an air mix door 1 (corresponding to an example of a movable member) of a vehicle air conditioner as shown in FIG.

  Here, the air mix door 1 is a door member for controlling the flow of air conditioning air in the air conditioning casing 5 of the vehicle air conditioner shown in FIG. The air-conditioning air is cooled by the evaporator 4 and flows from the evaporator 4 through the vehicle interior outlet 6 into the vehicle interior. When the air mix door 1 is closed, the air conditioning air bypasses the heater core 3, and when the air mix door 1 is open, the air conditioning air passes through the heater core 3. When the air for air conditioning passes through the heater core 3, the heater core 3 heats the air for air conditioning passing through the heater core 3 using the cooling water of the engine 2 as a heat source.

  Depending on the position of the air mix door 1, the ratio of the air volume of the air-conditioning air flowing around the heater core 3 and the air volume of the air-conditioning air passing through the heater core 3 changes. Therefore, by controlling the position of the air mix door 1, the temperature of the air-conditioning air blown out from the vehicle interior outlet 6 into the vehicle interior can be adjusted.

  The heat exchanger such as the heater core 3 and the evaporator 4 and the air mix door 1 are accommodated in an air conditioning casing 5 made of resin, and the motor actuator is fixed to the air conditioning casing 5 by fastening means such as screws. The

  For example, the following method is used as a method of adjusting the temperature of the air blown into the passenger compartment. That is, the motor actuator according to the present embodiment detects the temperature of the air (air outlet temperature) blown out from the vehicle air conditioner into the vehicle interior using a temperature sensor (not shown), and further based on the setting operation of the vehicle occupant and the like. Then, the target value of the passenger compartment temperature is determined, and the target position of the air mix door 1 is calculated so that the detected outlet temperature approaches the target value. Then, the motor actuator displaces the position of the air mix door 1 to the determined target position.

  FIG. 2 is an external view of the motor actuator 100 ((a) is a front view, (b) is a side view), and FIG. 3 is an internal configuration diagram of the motor actuator 100. The motor actuator 100 has a DC motor 110 and a speed reduction mechanism 120 as an electric motor. The motor 110 has an output shaft 111 that rotates by obtaining electric power from a battery (not shown) mounted on the vehicle, and the speed reduction mechanism 120 decelerates the rotational force input from the output shaft 111 of the motor 110. Then, the speed change mechanism that outputs toward the air mix door 1. Hereinafter, a mechanism unit that rotationally drives the DC motor 110 and the speed reduction mechanism 120 is referred to as a drive unit 130.

  The speed reduction mechanism 120 is a gear train including a worm 121 press-fitted into the output shaft 111 of the DC motor 110, a worm wheel 122 meshing with the worm 121, and a plurality of spur gears 123 and 124. The step gear (output side gear) 126 is provided with an output shaft 127. The operation of the speed reduction mechanism 120 causes the output shaft 127 to rotate in accordance with the rotation of the output shaft 111 of the DC motor 110. At this time, the rotational angular velocity of the output shaft 127 becomes smaller than the rotational angular velocity of the output shaft 111.

  The motor actuator 100 has a casing 140 that houses the drive unit 130. Further, the motor actuator 100 has contact brushes 155 to 157 fixed to the casing 140.

  Further, as shown in FIGS. 3 to 6, the speed reduction mechanism 120 rotates integrally with the output shaft 127 from the input gear (worm 121) directly driven by the DC motor 110 to the output side (output shaft 127). A pulse pattern plate (hereinafter simply referred to as a pattern plate) 153 is provided as a non-conductive printed board.

  The angular range in the circumferential direction around the rotation center of the pattern plate 153 is divided into a rotation detection area 300 and an initialization area 301 as shown in FIG. The rotation detection area 300 is used to generate a pulse signal pattern used to detect the rotation angle of the pattern plate 153, as will be described later. The initialization area 301 is used to generate a pulse signal pattern (hereinafter referred to as an initialization signal pattern) indicating the origin position of the pattern plate 153 (or the air mix door 1).

  A conductor pattern is printed on one surface of the pattern plate 153 (hereinafter referred to as a pattern surface). Hereinafter, this conductor pattern will be described. In the following description, the rotation center of the pattern plate 153 is simply referred to as the rotation center, and the distance from the rotation center on the pattern surface is referred to as the center distance. Further, the circumference around the center of rotation is simply called the circumference. The angle on the pattern surface viewed from the center of rotation is simply referred to as the center angle. Further, an angle range in which each part on the pattern surface is viewed from the rotation center is referred to as an angular width of the part. Note that the angle width is the same as the time width if the rotational angular velocity of the pattern plate 153 is constant. In the present embodiment, the rotational angular velocity when the pattern plate 153 is rotated is controlled to be constant.

  As shown in FIGS. 4 and 6, the conductor pattern has a plurality of (for example, 100 or more) conductive portions 151 a, the same number of conductive portions 152 a as the conductive portions 151 a, and one conductive portion 154 a. .

  The shape of the conductive portion 151a is a shape obtained by removing a sector having the same angle with a radius r2 (r2 <r1) from a sector having a radius r1. The shape of the conductive portion 152a is a shape obtained by removing a sector having the same angle with a radius r3 (r3 <r2) from a sector having a radius r2. The shape of the conductive portion 154a is a shape obtained by removing a sector having the same angle with a radius r4 (r4 <r3) from a sector having a radius r3.

  The conductive portions 151a are arranged in a line on the circumference having the largest center distance among the conductive portions 151a, 152a, and 154a. Each of the plurality of portions 151b existing between the conductive portions 151a is a non-conductive portion 151b in which a conductor pattern is not formed. Hereinafter, a pattern of change in conductivity / non-conductivity along the circumferential direction including the plurality of conductive portions 151a and the plurality of non-conductive portions 151b is referred to as a first pattern 151.

  In addition, the conductive portions 152a are arranged in a line on a circle having the second largest center distance among the conductive portions 151a, 152a, and 154a. Each of the plurality of portions 152b existing between the conductive portions 152a is a non-conductive portion 152b where a conductor pattern is not formed. Hereinafter, a conductive / non-conductive change pattern along the circumferential direction including the plurality of conductive portions 152 a and the plurality of non-conductive portions 152 b is referred to as a second pattern 152.

  In addition, the conductive portion 154a is arranged across the entire rotation detection region 300 and both end portions of the initialization region 301 on the circumference having the smallest center distance among the conductive portions 151a, 152a, and 154a. ing. In the initialization region 301, there is one portion 154b that exists between both ends of the conductive portion 154a in the circumferential direction. This portion 154b is a non-conductive portion 154b where no conductor pattern is formed. The pattern of change of conductivity / non-conductivity along the circumferential direction composed of one conductive portion 154a and one non-conductive portion 154b is hereinafter referred to as a common pattern 154.

  In the rotation detection region 300, the angle widths of the conductive portions 151a are all equal to the angle α1, and the angle widths of the non-conductive portions 151b are all equal to the angle β1. In the rotation detection region 300, the angle widths of the conductive portions 152a are all equal to the angle α2, and the angle widths of the non-conductive portions 152b are all equal to the angle β2. Note that a relationship of α1 = α2 = β1 = β2 holds between the angles α1, α2, β1, and β2.

  In the rotation detection region 300, the phase of the conductive and non-conductive patterns in the circumferential direction (specifically, the phase of the central angle) is shifted between the first pattern 151 and the second pattern 152. Yes. That is, the first pattern 151 and the second pattern 152 are not switched to the conductive portion at the same central angle position along the circumferential direction, and are not switched to the non-conductive portion at the same central angle position. It is not designed to switch. The angle at which the shift between the first pattern and the second pattern is estimated from the rotation center is ½ of α1 (= α2 = β1 = β2).

  In the initialization region 301, the first and second pulse patterns 151 and 152 are composed of only the conductive portions 151a and 152a, respectively, and the common pattern 154 includes the non-conductive portion 154b at both ends of the conductive portion 154a from the circumferential direction. It is supposed to be sandwiched between.

  Here, the conductive portion 151 a of the first pattern 151 is electrically connected to the conductive portion 152 a of the second pattern 152. In addition, the conductive portion 151 a of the first pattern 151 and the conductive portion 152 a of the second pattern 152 are electrically connected to the conductive portion 154 a of the common pattern 154.

  On the other hand, on the casing 140 side, first to third contact brushes (electrical contacts) 155 to 157 made of a copper-based conductive material connected to the positive electrode side of the battery are fixed by resin integral molding, and the first contact brush 155. Is in contact with the first pulse pattern 151, the second contact brush 156 is in contact with the second pulse pattern 152, and the third contact brush 157 is in contact with the common pattern 154.

  In the present embodiment, the first to third contact brushes 155 to 157 are provided with two or more contacts (four points in the present embodiment) between the first to third contact brushes 155 to 157 and the pattern plate 153. And the conductive portions 151a, 152a, and 154a are securely connected.

  As shown in FIG. 2, a link lever 160 that swings the air mix door 1 is press-fitted and fixed to the output shaft 127. Therefore, the position of the air mix door 1 can be controlled by controlling the rotation angle of the output shaft 127 (that is, the operating position of the output shaft 127). The air conditioning casing 5 is provided with stoppers 5a and 5b. The stoppers 5a and 5b are used to stop the rotation of the DC motor 110 by causing the link lever 160 to collide when electrical regulation of the rotation of the DC motor 110 fails.

  Next, an outline of the operation of the actuator 100 will be described. FIG. 7 is a schematic diagram of a circuit configuration of the electric control circuit 200 of the actuator 100. The electric control circuit 200 includes a constant voltage circuit 211, a reset determination circuit 212, a CPU 213 (corresponding to an example of a detection unit), a motor drive circuit 214, an EEPROM 215, and a pulse signal detection circuit 216.

  The constant voltage circuit 211 is a circuit for applying a constant voltage as much as possible to the circuits in the electric control circuit 200 such as the CPU 213 and the pulse signal detection circuit 216 by using power supply from a power source (for example, a battery). is there.

  The reset determination circuit 212 is a circuit that detects the voltage applied from the constant voltage circuit 211 and resets the CPU 213 when the detected voltage falls below a predetermined reset determination level. Specifically, as shown in the timing chart of FIG. 8, when the applied voltage 50 from the constant voltage circuit 211 falls below the reset determination level, the reset signal 51 from the reset determination circuit 212 to the CPU 213 is switched from OFF to ON. The operation mode 52 of the CPU 213 shifts from the normal operation to the reset based on the reset signal 51 being turned on. When the applied voltage 50 returns to the reset determination level or higher, the reset signal 51 returns from ON to OFF, the operation mode of the CPU 213 returns to normal operation, and the CPU 213 is restarted.

  The CPU 213 executes a program in a ROM (not shown) to execute processing as will be described later. In this execution, the CPU 213 controls the operation of the DC motor 110, and the air mix door 1 is activated by the operation of the DC motor 110. Detect position.

  The CPU 213 includes a RAM 213a such as an SRAM. The RAM 213a is a volatile storage medium that cannot retain stored contents when power supply is cut off. The CPU 213 erases the contents of the RAM 213a when resetting by a reset signal from the reset determination circuit 212. Therefore, the RAM 213a cannot hold the stored information when the voltage applied to the CPU 213 falls below a predetermined level.

  The motor drive circuit 214 is a circuit that drives the DC motor 110 under the control of the CPU 213. The EEPROM 215 is a storage circuit that can hold input and stored information without receiving power. The EEPROM 215 can be replaced with any storage circuit such as a flash memory or a magnetic storage medium as long as it is a storage circuit (that is, a non-volatile storage medium) that can hold input and stored information without receiving power. May be. Even when the CPU 213 is reset, the EEPROM 215 holds the information that has been input and stored.

  The pulse signal detection circuit 216 is a circuit that detects a pulse signal generated on the pattern plate 153 and outputs the detected result to the CPU 213.

  The pulse output unit 158 includes first to third contact brushes 155, 156, and 157 and a pattern plate 153, and is a circuit that outputs a pulse signal according to the rotation of the output shaft 127. In FIG. 7, the pulse output unit 158 is replaced with an electrically equivalent diagram. This pulse output unit 158 outputs an initialization signal pattern indicating the origin position and a pulse signal for detecting the rotation of the output shaft 127.

  The switch 158a is configured by the first contact brush 155 and the first pattern 151, and switches according to the rotation of the output shaft 127. That is, on / off is switched according to the rotation of the output shaft 127. Specifically, the switch 158a is turned on while the contact portion 155a of the contact brush 155 is in contact with the conductive portion 151a. Further, since the contact portion 155a of the contact brush 155 is in the non-conductive portion 151b, the switch 158a is turned off while not in contact with the conductive portion 151a.

  The switch 158b is configured by the second contact brush 156 and the second pattern 152, and switches according to the rotation of the output shaft 127. Specifically, the switch 158b is turned on while the contact portion 156a of the contact brush 156 is in contact with the conductive portion 152a. Further, the switch 158b is turned off while the contact portion 156a of the contact brush 156 is in the non-conductive portion 152b and is not in contact with the conductive portion 152a.

  Further, the switch 158c is configured by the third contact brush 157 and the common pattern 154, and switches according to the rotation of the output shaft 127. Specifically, the switch 158c is turned on while the contact portion 157a of the contact brush 157 is in contact with the conductive portion 154a. Further, the switch 158c is turned off while the contact portion 156a of the contact brush 157 is in the non-conductive portion 154b and is not in contact with the conductive portion 154a.

  One end of the switch 158c, that is, one end of the third contact brush 157 is electrically connected to the ground. The pulse signal detection circuit 216 has a pull-up resistor at each connection point with the switches 158a and 158b. Accordingly, A-phase and B-phase pulse signals are generated from the switches 158a and 158b in accordance with the on / off changes of the switches 158a, 158b and 159c accompanying the rotation of the output shaft 127, respectively.

  As a specific operation for generating the pulse signal, first, the DC motor 110 is driven by the motor driving circuit 214, and the pattern plate 153 and the output shaft 127 are rotated according to the driving of the DC motor 110, and the first to third contact brushes 155. The case where ˜157 is in contact with the rotation detection region 300 will be described with reference to FIG. 9.

  In this case, while the third contact brush 157 is in contact with the conductive portion 154a, the first contact brush 155 is in an energized (ON) state in contact with the conductive portion 151a and in the non-conductive portion 151b and does not contact the conductive portion 151a. The non-energized (OFF) state occurs alternately, and in the second contact brush 156, the energized (ON) state in contact with the conductive portion 152a and the non-energized state in the non-conductive portion 152b and not in contact with the conductive portion 152a ( OFF) state occurs alternately.

  FIG. 9 schematically shows changes in pulse signals generated in the first and second contact brushes 155 and 156 in this case. The horizontal axis direction (left-right direction) in FIG. 9 indicates the central angle. The upper part of FIG. 9 shows the change in the contact relationship between the contact brushes 155 to 157 and the patterns 151, 152, and 154 as the pattern plate 153 rotates. The hatched portions correspond to the conducting portions 151a, 152a, and 154a, and the portions without hatched portions correspond to the non-conducting portions 151b, 152b, and 154b. The lower part of FIG. 9 shows changes in the A-phase pulse signal (that is, the signal pattern 191) and changes in the B-phase pulse signal (that is, the signal pattern 192) in accordance with the change in the contact relationship.

  As shown in this figure, the switching timing between the energized state and the non-energized state of the first contact brush 155 is shifted from the switching timing of the energized state and the non-energized state of the second contact brush 156. Therefore, when the pattern plate 153 rotates in the positive rotation direction (clockwise direction in FIG. 6, left direction in FIG. 9), the contact points between the contact brushes 155 to 157 and the patterns 151, 152, and 154 change. In the A phase, the signal is low level “0” in the normal state where the contact brush 155 is in contact with the conductive portion 151a, and the signal is high level “1” in the non-energized state where the contact brush 155 is not in contact with the conductive portion 151a. " Similarly, in the B phase, the signal is low level “0” in the normal state where the contact brush 156 is in contact with the conductive portion 152a, and the signal is high level in the non-energized state where the contact brush 156 is not in contact with the conductive portion 152a. “1”.

  Therefore, when the combination of the signal levels of the A phase and the B phase is described in the form of “A phase level, B phase level”, the signal level becomes “1” as the pattern plate 153 rotates in the forward rotation direction. , 0 ”,“ 1, 1 ”,“ 0, 1 ”,“ 0, 0 ”. Hereinafter, the circulation pattern of this combination of pulse signals is referred to as a positive rotation signal pattern. Conversely, as the pattern plate 153 rotates in the reverse rotation direction (the direction opposite to the normal rotation direction), the signal levels are “0, 0”, “0, 1”, “1, 1”, “1”. , 0 ”in a cyclical order. Hereinafter, the circulation pattern of this combination of pulse signals is referred to as a reverse rotation signal pattern.

  Hereinafter, a state where the signal level is “0, 0” is referred to as an all contact state, a state where the signal level is “1, 1” is referred to as a non-contact state, and a state where “1, 0” or “0, 1” is illustrated. It is referred to as a partial contact and partial non-contact state.

  As a specific operation for generating the pulse signal, the DC motor 110 is rotated, the pattern plate 153 and the output shaft 127 are rotated, and the first, second, and third contact brushes 155, 156, and 157 are moved to the initialization region 301. The case of contact will be described with reference to FIG. The description format of FIG. 10 is substantially the same as FIG. However, the upper part and the lower part are interchanged.

  In this case, as shown in FIG. 10, the third contact brush 157 and the conductive portion 154a are kept in the energized (ON) state where the first and second contact brushes 155 and 156 are in contact with the conductive portions 151a and 152a. From the energized (ON) state in contact with each other, the non-energized (OFF) state in which the third contact brush 157 and the non-conductive portion 154b contact each other, and then the energization (ON) in which the third contact brush 157 and the conductive portion 154a contact each other. ) State (conductive portion → non-conductive portion → conductive portion).

  Therefore, the first and second contact brushes 155 and 156 generate two-phase pulse signals (A phase and B phase) of the initialization signal pattern shown in FIG. 10 according to the rotation of the DC motor 110. This initialize signal pattern is not a pattern in which the amplitudes of the two-phase pulse signals are shifted alternately as shown in FIG. 9, but the two-phase pulse signals are simultaneously switched from the low level “0, 0” to the high level signal. The pattern is switched to “1, 1” and simultaneously switched from the high level signal to the low level signal “0, 0”.

  As is apparent from the above description, in this embodiment, the switch means 158a to 158c for generating a pulse signal each time the output shaft 127 rotates by a predetermined angle by the first and second contact brushes 155, 156 and 157 and the pattern plate 153. A pulse generator (pulse generating means) 158 (see FIG. 7) is configured.

  As already described, the switch means 158a and 158b are constituted by the contact brushes 155 and 156 and the first and second patterns 151 and 152, and are connected in parallel between the constant voltage circuit (power supply circuit) and the ground. And switching individually to generate a pulse signal based on the rotation of the electric motor 110. The switch means 158c is composed of the third contact brush 157 and the common pattern 154, and switches between the switch means 158a, 158b and the ground based on the rotation of the electric motor 110.

  Further, since the phase of the first pattern 151 and the phase of the second pattern 152 are shifted, the pulse generator 158 has an A-phase pulse signal 191 generated by the first pattern 151 and the first contact brush 155, and A phase shift also occurs between the B-phase pulse 192 generated by the second pattern 152 and the second contact brush 156.

  By utilizing this, in the present embodiment, the rising edge of any one of the A-phase pulse and the B-phase pulse (that is, the switching of the signal level from “0” to “1”) first occurs in the pulse signal detection circuit 216. , The rotational direction of the DC motor 110 (output shaft 127) is detected.

  Next, a motor control process executed by the CPU 213 of the electric control circuit 200 will be described. 11 and 12 show a flowchart of this motor control process. When the ignition switch (IG) of the vehicle is turned on, the CPU 213 first determines in step S105 whether or not the IG switch is currently turned on. If it is on, the CPU 213 proceeds to step S110. The process proceeds to the IG off process of FIG. The ignition switch serves as a start permission switch that permits supply of electric power to the DC motor 110.

  As a case where it is determined in step S105 that it is off, there is a case where IG is turned off immediately after IG is turned on. Such a case occurs, for example, when the driver is rapidly switching on and off of the IG by failing to start the engine.

  In the IG off process, the CPU 213 first determines in step S340 whether or not there is a pulse skip, and if there is a pulse skip, executes step S365. If there is no pulse skip, the CPU 213 subsequently executes step S350. A pulse skip means that disorder occurs in the order of pulse signals (for example, a forward rotation signal pattern and a reverse rotation signal pattern). Whether or not a pulse skip has occurred is determined by whether or not a pulse skip flag is recorded in the EEPROM 215. This pulse skip flag is recorded in step S190 in FIG. 11, as will be described later.

  In step S365, the pulse skip flag and a pulse stop flag described later are erased from the EEPROM 215, the initial position is set, and then the process proceeds to step S370. In the initial position setting, the CPU 213 outputs a control signal to the motor drive circuit 214 to drive the DC motor 110 so that the pattern plate 153 rotates in a predetermined initialization direction (for example, the reverse rotation direction). The A-phase and B-phase pulse signals 191 and 192 output from the pulse output unit 158 according to the driving of the DC motor 110 are detected by the pulse signal detection circuit 216, and the pulses detected by the pulse signal detection circuit 216 are detected. It waits until the initialization signal pattern is included in the signal, that is, until the ends of the contact brushes 155 to 157 reach the initialization region 301. And when it reaches | attains, the drive of the DC motor 110 is stopped and the stop position is set to an origin position.

  The setting of the origin position is realized by setting both the current value of the pulse count in the RAM 213a and the origin value of the pulse count in the memory of the CPU 213 to a predetermined origin reference value (for example, 1). Note that the value recorded in the ROM of the CPU 213 may be used as the data of the predetermined origin reference value.

  Here, the pulse count is increased by one count whenever the combination of high and low of the A-phase and B-phase pulse signals changes in the forward rotation direction, and decreases by one count every time when the combination changes in the reverse rotation direction. It is a count. For example, regarding the positive rotation direction, when the signal level of the A phase and the B phase changes from “1, 0” to “1, 1”, changes from “1, 1” to “0, 1”, “ When changing from “0, 1” to “0, 0” and when changing from “0, 0” to “1, 0”, the pulse count increases by one count.

  In step S350, it is determined whether or not there is a pulse stop. If there is a pulse stop, step S360 is subsequently executed. If there is no pulse stop, step S370 is subsequently executed. The pulse stop means that the pulse signal does not change even though the direct current motor 110 is controlled to rotate. Whether or not the pulse is stopped is determined by whether or not a pulse stop flag is recorded in the EEPROM 215. This pulse stop flag is recorded in step S220 of FIG. 11, as will be described later.

  In step S360, a control signal is output to the motor drive circuit 214, and the DC motor 110 is moved in a direction opposite to the direction in which the DC motor 110 was rotating immediately before the change of the pulse signal was stopped (for example, 1 second). ) After that, in step S365, initial position setting is performed. As described above, by rotating the DC motor 110 in the opposite direction before the initial position setting, the locking phenomenon of the actuator 100 due to the biting of foreign matter or the like can be spontaneously eliminated, and consequently the actuator 100 reliability and durability can be improved. Following step S360, an initial position is set in step S365, and then the process proceeds to step S370.

  In step S370, the current value of the pulse count in the RAM 213a is recorded in the EEPROM 215 as stop position data. The current value of the pulse count recorded as the stop position data is a value corresponding to the operating position of the output shaft 127 stopped at the origin position in step S365, or stopped in step S150 of FIG. This value corresponds to the operating position of the output shaft 127 in the state.

  Subsequently, in step S375, the process waits until a predetermined time elapses from when the ignition switch is turned off (that is, IG is turned off). When the predetermined time elapses, subsequently, in step S380, the battery removal determination flag is set in the EEPROM 215. To record.

  The predetermined time is shorter than the time for stopping the power supply from the battery to the in-vehicle electric device in order to suppress the consumption of dark current. For this reason, when the battery removal determination flag is held in the EEPROM 215, it means that the motor actuator 100 is not disconnected from the battery. When the battery removal determination flag is not held in the EEPROM 215, the battery is removed from the battery. This means that the motor actuator 100 is disconnected. After step S380, the operation of the motor actuator 100 is stopped.

  In this way, when the IG is off, if the pulse skip (S340) or pulse stop (S350) is before the IG off, the operating position of the output shaft 127 is returned to the initial position and stopped (S365). Is recorded in the EEPROM 215 as a stop position (S370). If the pulse skip (S340) or pulse stop (S350) is not before IG OFF when the IG is OFF, the operation position of the output shaft 127 stopped at the target position (S150) is set as the stop position in the EEPROM 215. Recording is performed (S370).

  After that, when IG is turned on and the CPU 213 determines that IG is turned on in step S105 of FIG. 11, subsequently, in step S110, the data of the origin position (that is, the origin value of the pulse count) and the data of the stop position (that is, the pulse) It is determined whether or not a data set of (the current value of the count) is held in the RAM 213a. If it is determined that it is not retained, the process proceeds to step S112. If it is determined that it is retained, the process proceeds to step S116.

  If the combination of the origin position data and the stop position data is not held in the RAM 213a before the determination in step S110, the motor actuator 100 is disconnected from the battery and the power supply to the electric control circuit 200 is stopped. If this happens, or if the voltage applied from the constant voltage circuit 211 falls below the reset determination level for some reason, the CPU 213 resets and restarts.

  In particular, in the latter case, there is a high possibility that it will occur immediately after IG is turned on. Immediately after the IG is turned on, the load on the battery increases due to engine start or the like, and the applied voltage from the battery to the electric control circuit 200 decreases. As a result, the applied voltage to the CPU 213 often falls below the reset determination level. Because. Note that the CPU 213 after resetting and restarting starts again from step S105.

  In step S112, it is determined whether or not stop position data is held in the EEPROM 215. If held, the process proceeds to step S114. If not held, the process proceeds to step S120. If stop position data is recorded in the EEPROM 215 in step S370 of the immediately preceding IG off process, the determination result is affirmative.

  In step S114, stop position data and origin position data are recorded in the RAM 213a. Specifically, the stop position data currently held in the EEPROM 215 is recorded in the RAM 213a as the current value of the pulse count (corresponding to an example of the operation position data), and the data of a predetermined origin reference value is Recorded in the RAM 213a as the pulse count origin value. Subsequent to step S114, step S116 is executed.

  In step S116, the stop position data in the EEPROM 215 is erased, and then step S118 is executed. In step S118, it is determined whether or not the battery removal determination flag is recorded in the EEPROM 215. If it is not recorded, step S120 is subsequently executed. If it is recorded, step S122 is subsequently executed.

  In step S120, the initial position is set by the same method as in step S365 of the IG off process, and then the process proceeds to step S124. When the initial position is set, a set of origin position data and stop position data is recorded in the RAM 213a. In step S122, the battery removal determination flag is deleted, and then the process proceeds to step S124.

  As a result of the processing in steps S105 to S122 performed by the CPU 213, the CPU 213 determines that the EEPROM 215 is not turned on immediately before the IG is turned off when the origin position data and stop position data are not stored in the RAM 213a when the IG is turned on (see step S110). Are recorded in the RAM 213a as the operation position data (current value of the pulse count) and the origin position data (origin value of the pulse count) of the output shaft 127 (step S112). , S114).

  In this way, when the motor actuator 100 is disconnected from the battery after the previous IG is turned off, or when the applied voltage from the constant voltage circuit 211 decreases immediately after the IG is turned on and the CPU 213 is reset and restarted, Even if the set of the origin position data and the stop position data disappears from the RAM 213a, the set can be held again in the RAM 213a without performing the initial position setting. Therefore, the frequency of initial position setting can be reduced, and the life of the motor actuator 100 can be extended.

  It should be noted that the stop position data held again in the RAM 213a surely matches the current stop position is that the stop position data is recorded in the EEPROM 215 immediately before the motor actuator 100 is stopped, and from the EEPROM 215. The stop position data is recorded in the RAM 213a because it is after the IG is turned on (or after the CPU 213 is reset and restarted) and before the DC motor 110 is driven.

  However, when the battery removal determination flag is not in the EEPROM 215, that is, when the motor actuator 100 is disconnected from the battery immediately after the IG is turned off (specifically, within a predetermined time), the operation of removing the motor actuator 100 is performed. There is a high possibility that a person rotates the motor for maintenance or testing purposes, and then attaches the motor actuator 100 to the battery again. In such a case, the stop position data recorded in the EEPROM 215 does not match the actual operating position of the output shaft 127.

  For this reason, in this embodiment, when the battery removal determination flag is not recorded in the EEPROM 215, the initial position setting is executed even if stop position data exists in the EEPROM 215 (see step S118 → step S120). Thus, the current position data returned to the RAM 213a and the actual stop position of the output shaft 127 are surely matched.

  That is, when the vehicle ignition switch is turned on, if the power supply to the electric control circuit 200 is not cut off within a predetermined time since the vehicle ignition switch was turned off last time, the data is recorded from the EEPROM 215 to the RAM 213a. The stopped position data is used in steps S124 to S220 as the operating position data of the output shaft 127. And when the ignition switch of the vehicle is turned on, if the power supply to the electric control circuit 200 has been cut off within a predetermined time since the last time the ignition switch of the vehicle was turned off, the output shaft 127 is set to the predetermined value. The DC motor 110 is controlled so as to return to the origin position, and the position data corresponding to the origin position is recorded in the RAM 213a, and the recorded position data corresponding to the origin position is recorded as the operation position of the output shaft 127. Data may be used in steps S124 to S220.

  In addition, after the current position data in the EEPROM 215 is recorded in the RAM 213a, the current position data in the EEPROM 215 is erased before the DC motor 110 is operated. By doing in this way, even if the applied voltage from the constant voltage circuit 211 is lowered for some reason and the CPU 213 is reset and restarted after the operating position of the output shaft 127 is changed after step S124, the current state is maintained. The current position data in the incompatible EEPROM 215 is not recorded in the RAM 213a.

  Each time the operating position of the output shaft 127 changes after step S124, the current position data in the RAM 213a may be recorded in the EEPROM 215 following the change. However, in that case, the number of times of recording in the EEPROM 215 becomes very large as compared to the case where it does not.

  In step S124 following step S122, the CPU 213 determines whether the IG switch is on or off. If it is on, the CPU 213 executes step S130. If it is off, the CPU 213 executes IG off processing.

  In step S130, a target value is set. The target value is a relative pulse count value from the origin position, which is determined based on the target position of the air mix door 1. Information on the correspondence between the target position of the air mix door 1 and the target value of the pulse count may be recorded in advance in the memory of the electric control circuit 200. In that case, the CPU 230 specifies the target value of the pulse count from the target position of the air mix door 1 based on the information on the correspondence relationship.

  Subsequently, in step S140, the target value of the pulse count is compared with the current relative value to determine whether or not they match. Here, the current relative value is a value obtained by subtracting the origin value of the pulse count from the current value of the pulse count. If they match, the motor drive circuit 214 is controlled in step S150 to stop the DC motor 110, and then the process returns to step S124.

  If it is determined in step S140 that they do not match, then in step S160, the motor drive circuit 214 is controlled to rotate the DC motor 110. Specifically, the DC motor 110 is rotated so that the pattern plate 153 rotates in a direction in which the current position approaches the target position. The current value of the pulse count in the RAM 213a is changed based on the change in the combination of the A-phase and B-phase signals from the pulse signal detection circuit 216. Specifically, when the combination of A-phase and B-phase signals changes once in the forward rotation pattern, the current value of the pulse count is increased by 1 count, and the combination of A-phase and B-phase signals in the reverse rotation pattern becomes 1. When the number of times changes, the current value of the pulse count is decreased by one count.

  Subsequently, in step S170, it is determined whether or not there is a change in the two-phase pulse detected by the pulse signal detection circuit 216. If there is a change (that is, the output shaft 127 is rotating), then step S180 is performed. When there is no change (that is, when the output shaft 127 is not rotating), the process proceeds to step S200.

  When step 200 is executed, the change of the pulse signal is stopped despite the drive current being supplied to the DC motor 110. In such a case, there is a high possibility that an abnormality has occurred in the rotation of the pattern plate 153. Therefore, subsequently, in step S200, it is determined whether or not the period during which the change of the pulse signal has stopped after the start of drive control has exceeded a predetermined time. If not, the process returns to step S124. If it has exceeded, it is determined in step S210 that an abnormality has occurred in the pulse signal, the motor drive circuit 214 is controlled to stop energization of the drive current, the DC motor 110 is stopped, and step S220. Then, a pulse stop flag indicating that the change of the pulse signal is stopped is recorded in the EEPROM 215. After step S220, step S124 is executed again.

  Further, in step S180, which is executed when the DC motor 110 is energized and the pulse signal changes, the pulse waveform detected by the pulse signal detection circuit 216 (see FIG. 9) is disturbed. It is determined whether or not pulse signals are generated in a regular order without generation, that is, whether or not pulse skipping has occurred. When no pulse skipping has occurred, the process returns to S124. If a pulse skip has occurred, a pulse skip flag indicating that a pulse skip has occurred is recorded in the EEPROM 215 in step S190. After step S190, step S124 is executed again.

  In this way, when the pulse is stopped, the pulse stop flag is recorded in the EEPROM 215, and when the pulse is skipped, the pulse skip flag is recorded in the EEPROM 215. In both cases, the initial value can be set in the off process.

  In this way, the DC motor 110 is driven by the processing of steps S140, S150, and 160 until the current relative value matches the pulse count of the target value (specifically, the relative pulse count with respect to the reference value of the origin) When they match, the driving of the DC motor 110 is stopped.

  In this way, the electric control circuit 200 detects a change in the combination of contact and non-contact of the contact brushes 155 and 156 with the conductor pattern, thereby the pattern plate 153 (or DC motor) corresponding to the position of the air mix door 1. 110), and the DC motor 110 can be feedback-controlled so that the difference between the detected current value and the origin value matches the target value.

  As mentioned above, although embodiment of this invention was described, the scope of the present invention is not limited only to the said embodiment, The various form which can implement | achieve the function of each invention specific matter of this invention is included. It is.

It is a schematic diagram of the vehicle air conditioner used as the application example of the motor actuator which concerns on embodiment of this invention. 1 is an external view of a motor actuator 100. FIG. 2 is a schematic diagram of an internal configuration of a motor actuator 100. FIG. (A) is a front view of the pattern plate 153, (b) is a side view of (a). It is AA sectional drawing of FIG. 4 is an enlarged view of a pattern plate 153. FIG. 2 is a schematic diagram showing an electrical control circuit 200. FIG. FIG. 11 is a timing chart showing changes in applied voltage 50 from constant voltage circuit 211, reset signal 51 from reset determination circuit 212 to CPU 213, and operation mode 52 of CPU 213. FIG. 6 is a diagram showing a pattern of a pulse signal output for detecting a rotation angle in the rotation detection region 300. 6 is a chart showing a pattern of pulse signals output in the initialization region 301. It is a flowchart of the motor control process which CPU213 of the electric control circuit 200 performs after starting. It is a flowchart of the motor control process which CPU213 of the electric control circuit 200 performs at the time of IG OFF.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air mix door 100 Motor actuator 110 DC motor 127 Output shaft 151a, 152a, 154a Conductive part 151b, 152b, 154b Non-conductive part 153 Pattern plate 155, 156, 157 Contact brush 158 Pulse output part 200 Electric control circuit 211 Constant voltage circuit 212 Reset determination circuit 213 CPU
213a RAM
214 Motor drive circuit 215 EEPROM
216 Pulse signal detection circuit 300 Rotation detection area 301 Initialization area

Claims (3)

A motor actuator mounted on a vehicle,
A motor (110);
An output shaft (127) that rotates as the motor (110) rotates;
A pulse output unit (158) for outputting a pulse signal that changes with rotation of the output shaft (127);
A detection unit (213) for detecting an operating position corresponding to a rotation angle of the output shaft (127) based on a change in a pulse signal from the pulse output unit (158);
A non-volatile storage medium (215) capable of holding stored information without receiving power supply,
The detection unit (213) includes a volatile storage medium (213a) that cannot retain stored information when a voltage applied to the detection unit (213) falls below a predetermined level.
Further, the detection unit (213) updates the data of the operation position in the volatile storage medium (213a) according to the detected change of the operation position,
Furthermore, the detection unit (213) uses the operation position data in the volatile storage medium (213a) as stop position data based on the fact that the ignition switch of the vehicle is turned off as the nonvolatile storage. Recorded on the medium (215),
Further, the detection unit (213) detects the stop position data recorded in the nonvolatile storage medium (215) based on the ignition switch of the vehicle being turned on, on the output shaft (127). A motor actuator, wherein the data is recorded in the volatile storage medium (213a) as operating position data.   The detection unit (213) reads the stop position data recorded in the non-volatile storage medium (215) before the output shaft (127) rotates after the ignition switch of the vehicle is turned on. The motor actuator according to claim 1, wherein the data is recorded in the volatile storage medium (213a) as data of an operating position of the output shaft (127). When the ignition switch of the vehicle is turned on, the detection unit (213) cuts off the power supply to the detection unit (213) within a predetermined time after the ignition switch of the vehicle is finally turned off. If not, the stop position data recorded from the nonvolatile storage medium (215) to the volatile storage medium (213a) is used as the operating position data of the output shaft (127),
In addition, when the ignition switch of the vehicle is turned on, the detection unit (213) supplies power to the detection unit (213) within a predetermined time after the ignition switch of the vehicle is finally turned off. If it is disconnected, the motor (110) is controlled to return the output shaft (127) to a predetermined origin position, and the data of the position corresponding to the origin position is stored in the volatile storage medium (213a). The motor actuator according to claim 1 or 2, wherein the motor actuator is recorded and data of a position corresponding to the recorded origin position is used as data of an operating position of the output shaft (127).

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