JP2007151376A - Method of detecting origin of output shaft in motor actuator, and method of determining abnormality of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for detecting the origin of an output shaft in a motor actuator, capable of detecting the origin with high accuracy in the motor actuator, having a rotation detector for detecting the origin of the output shaft. <P>SOLUTION: In the origin detection method, an air conditioner ECU calculates the counted value, based on the leading and the falling edges of an inputted output pulse, based on the input of the output pulses of AB phases, in synchronization with the rotation of a motor rotary shaft of a drive motor. The air conditioner ECU calculates (detects) the intermediate value Nx of the count values Na, Nb, corresponding to respective leading and falling edges of the inputted origin detection pulse, based on the input of the origin detection pulse due to the arrangement of the origin of an output gear (output shaft), when the output shaft is rotated in one direction in the motor actuator as the origin of the output shaft. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for detecting the origin position of an output shaft in a motor actuator equipped with a rotation detection device capable of detecting the origin position of an output shaft that is rotationally driven, and an abnormality determination method for detecting the origin position.

  The vehicle air conditioner is provided with a motor actuator for operating a switching door that switches a ventilation path in the air conditioning duct. When the switching door is operated by this motor actuator, it is necessary to grasp the opening degree of the switching door. Therefore, in the motor actuator, an output shaft (output gear) of the actuator is detected in order to detect the opening degree of the switching door. ) Is detected.

  In addition, it is necessary to set the origin position of the switching door, which is a reference for detecting the opening degree of the switching door. Therefore, as a conventional method for setting the origin position, a method is known in which the motor actuator is operated to the lock position (mechanical limit position) and the lock position is set as the origin position. .

  However, since the switching door has a plate shape and is not so rigid, the switching door is bent when the switching door is locked. In addition, if the drive torque of the motor actuator changes due to environmental fluctuations such as temperature and power supply voltage, the amount of deflection of the switching door changes with the change of the drive torque, so the above method sets the origin position with high accuracy. There was a problem that I could not.

  Therefore, in the motor actuator disclosed in Patent Document 1, the driving torque and return amount of the motor actuator according to the environmental change so that the amount of deflection when the switching door is locked is constant regardless of the environmental change such as temperature and power supply voltage. A means for changing is provided. Incidentally, the motor that is the drive source of the motor actuator is a stepping motor, and the step amount of the motor is changed by the changing means.

Further, in the motor actuator of Patent Document 2, a substrate on which a pulse pattern is formed is mounted on one side of the output gear, and a plurality of contact brushes that come into contact with the pulse pattern are provided. A rotation detection device that outputs A and B phase output pulses that are 90 ° out of phase with each other and detects the rotational position of the output shaft based on detection of the output pulses is provided. Further, in this rotation detection device, the pulse pattern is configured so that a part of the A and B phase output pulses have the same phase, and the origin position is detected based on the detection of the same phase of the output pulse. It has become.
Japanese Patent Laid-Open No. 10-248295 JP 2004-215488 A

  By the way, the above-mentioned Patent Document 1 requires means for detecting temperature, power supply voltage, etc., and means for calculating the driving torque and return amount of the motor actuator based on detection of environmental fluctuations by the means. There is a concern that the control load will increase and the cost for control will increase.

  Further, in Patent Document 2, since the origin position of the switching door can be detected without locking the switching door, it is difficult to receive environmental fluctuations such as temperature and power supply voltage. However, since the origin position is detected by the output pulses of the A and B phases having the same phase, that is, the logic of each output pulse based on the edge of each output pulse, the temperature, power supply voltage, etc. Considering that the pulse width also fluctuates due to environmental fluctuations, there is still room for improving the origin position detection accuracy.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to accurately detect the origin position in a motor actuator including a rotation detection device that detects the origin position of the output shaft. An object of the present invention is to provide a method for detecting the origin position of an output shaft in a motor actuator capable of performing the above and a method for determining an abnormality in the origin position detection.

  In order to solve the above-mentioned problem, the invention described in claim 1 is composed of a drive motor that rotationally drives the motor rotation shaft and a plurality of reduction gears including an output gear having an output shaft. A first speed reduction mechanism that decelerates rotation and transmits it to the output shaft, and outputs the origin position detection pulse based on the position of the origin position of the output shaft, with either the output gear or the output shaft as the detection target. A rotation detection device, and a second rotation detection device that outputs either an output pulse synchronized with the rotation of the detection target, with either the motor rotation shaft or the reduction gear preceding the output gear as the detection target. A method for detecting an origin position of an output shaft in a motor actuator, wherein a count value is obtained by counting based on at least one of a rising edge and a falling edge of the output pulse. And calculating an intermediate value of the count values corresponding to the rising edge and the falling edge of the origin position detection pulse during one-way rotation of the output shaft as the origin position of the output shaft. .

  In the present invention, the first rotation detection device outputs an origin position detection pulse based on the arrangement of the origin position of the output shaft with either the output gear or the output shaft of the motor actuator as the detection target, and detects the second rotation. The device outputs an output pulse synchronized with the rotation of either the motor rotation shaft of the drive motor or the reduction gear preceding the output gear. A count value is calculated based on at least one of the rising edge and the falling edge of the output pulse, and the count value corresponds to each of the rising edge and the falling edge of the origin position detection pulse when the output shaft rotates in one direction. Is calculated as the origin position of the output shaft. Here, when environmental fluctuations such as temperature and power supply voltage occur, the pulse width of the origin position detection pulse increases or decreases, but the intermediate position of the pulse width does not change significantly. Therefore, as described in the present invention, by calculating (detecting) the intermediate value of the count values corresponding to the rising edge and the falling edge of the origin position detection pulse as the origin position of the output shaft, it is difficult to receive the above environmental fluctuations. The origin position detection accuracy is high.

  The invention according to claim 2 includes a drive motor that rotationally drives the motor rotation shaft and a plurality of reduction gears including an output gear having an output shaft, and reduces the rotation of the motor rotation shaft to the output shaft. A transmission speed reduction mechanism, a first rotation detection device that outputs either of the output gear or the output shaft as an object of detection and outputs an origin position detection pulse based on the arrangement of the origin position of the output shaft, and the motor rotation The origin position of the output shaft in a motor actuator comprising: a second rotation detector that outputs an output pulse synchronized with the rotation of the detection target, with either the shaft or the reduction gear preceding the output gear as a detection target In the detection method, the count value is calculated by counting based on at least one of the rising edge and the falling edge of the output pulse, and when the output shaft is rotating forward Calculating a first intermediate value of the count value corresponding to each of a rising edge and a falling edge of the origin position detection pulse, and a rising edge and a falling edge of the origin position detection pulse when the output shaft is reversed The gist is to calculate a second intermediate value of the count value corresponding to each of the first and second intermediate values, and to calculate a further intermediate value of the calculated first and second intermediate values as the origin position of the output shaft.

  In the present invention, the count value is calculated as in the first aspect of the present invention, and the first intermediate value of the count value corresponding to each of the rising edge and the falling edge of the origin position detection pulse during the forward rotation of the output shaft is obtained. A second intermediate value of the count value corresponding to each of the rising edge and the falling edge of the origin position detection pulse during the reverse rotation of the output shaft is calculated, and further intermediate between the calculated first and second intermediate values. The value is calculated as the origin position of the output shaft. Since the intermediate value calculated in this manner is also less susceptible to the environmental fluctuations as in the first aspect of the invention, the detection accuracy of the origin position is high. In addition, the edge of the origin position detection pulse at the time of forward rotation and reverse rotation may shift due to an assembly error of the rotation detection device or motor actuator, etc., but the influence is eliminated by using the calculation method as in the present invention. It is possible to improve the detection accuracy of the origin position.

  According to a third aspect of the present invention, there is provided a drive motor that rotationally drives the motor rotation shaft and a plurality of reduction gears including an output gear having an output shaft, and the rotation of the motor rotation shaft is reduced to an output shaft. A transmission speed reduction mechanism, a first rotation detection device that outputs either of the output gear or the output shaft as an object of detection and outputs an origin position detection pulse based on the arrangement of the origin position of the output shaft, and the motor rotation The origin position of the output shaft in a motor actuator comprising: a second rotation detector that outputs an output pulse synchronized with the rotation of the detection target, with either the shaft or the reduction gear preceding the output gear as a detection target In the detection method, the count value is calculated by counting based on at least one of the rising edge and the falling edge of the output pulse, and when the output shaft is rotating forward Corresponding to the intermediate value of the count value corresponding to each rising edge of the origin position detection pulse during reverse rotation or the falling edge of the origin position detection pulse during forward rotation and reverse rotation of the output shaft. The gist is to calculate the intermediate value of the count value as the origin position of the output shaft.

  In the present invention, the count value is calculated in the same manner as in the first aspect, and the intermediate value of the count value corresponding to each rising edge of the origin position detection pulse at the time of forward rotation and reverse rotation of the output shaft, or the positive value of the output shaft. An intermediate value of the count values corresponding to the falling edges of the origin position detection pulse during rotation and reverse rotation is calculated as the origin position of the output shaft. Since the intermediate value calculated in this manner is also less susceptible to the environmental fluctuations as in the first aspect of the invention, the detection accuracy of the origin position is high. Similarly to the first aspect of the present invention, even in the present invention, even if the edge of the origin position detection pulse at the time of forward rotation and reverse rotation is shifted due to an assembly error of the rotation detection device or the motor actuator, the influence can be eliminated. It is possible to further improve the detection accuracy of the origin position. In addition, it is possible to reduce the number of times the intermediate value is calculated and the count value used (stored) when calculating the intermediate value.

  According to a fourth aspect of the present invention, in the method for detecting the origin position of the output shaft in the motor actuator according to any one of the first to third aspects, the second rotation detection device detects the motor rotation shaft as a detection target. The gist of the present invention is to output an output pulse synchronized with the rotation of the motor rotation shaft.

  In this invention, since the second rotation detection device outputs an output pulse synchronized with the rotation of the motor rotation shaft, the output pulse can detect the origin position and rotation position (rotation angle) of the output shaft with high resolution. It is.

  According to a fifth aspect of the present invention, in the method for detecting the origin position of the output shaft in the motor actuator according to any one of the first to fourth aspects, the second rotation detection device is synchronized with the rotation of the detection target. The gist of the present invention is to output a pair of output pulses that are 90 ° out of phase with each other.

  In the present invention, the second rotation detection device outputs a pair of output pulses that are 90 ° out of phase with each other in synchronism with the rotation of the reduction gear in the preceding stage relative to the motor rotation shaft or output gear to be detected. The output pulse can detect the origin position and rotation position (rotation angle) of the output shaft with high resolution.

  According to a sixth aspect of the present invention, in the method for detecting an origin position of an output shaft in a motor actuator according to any one of the first to fifth aspects, the motor actuator uses the output shaft to perform air conditioning of a vehicle air conditioner. The gist of the invention is to drive a switching door that switches the air flow path in the duct.

  In this invention, the motor actuator drives the switching door for switching the air blowing path in the air conditioning duct of the vehicle air conditioner by its output shaft, and is disposed in an environment in which environmental fluctuations such as temperature and power supply voltage are likely to occur. Therefore, the effect applied to such a motor actuator is great.

  According to a seventh aspect of the present invention, in the method for detecting the origin position of the output shaft in the motor actuator according to any one of the first to sixth aspects, an origin for determining whether or not an abnormality has occurred in the origin position detection. An abnormality determination method for position detection, wherein a pulse width of the origin position detection pulse is detected, and an abnormality determination serving as a reference for determining whether or not the origin position detection is abnormal with the detected pulse width The gist is that a plurality of values are set on the upper side or the lower side, and a plurality of abnormality levels are determined based on a comparison between each abnormality determination value and the pulse width.

  In this invention, it is determined whether or not an abnormality has occurred in the origin position detection based on the pulse width of the origin position detection pulse, and a plurality of abnormality levels are determined by setting a plurality of abnormality determination values. Thereby, it is possible to cope with each abnormality level.

  According to an eighth aspect of the present invention, in the method for detecting the origin position of the output shaft in the motor actuator according to any one of the first to sixth aspects, an origin for determining whether or not an abnormality has occurred in the origin position detection. A method for determining an abnormality in position detection, wherein whether or not an abnormality has occurred in origin position detection by counting a change to another logic level during a period in which the origin position detection pulse is at a logic level for origin position detection. The gist is to calculate a determination count value for determination and determine a plurality of abnormal levels according to the numerical value of the determination count value.

  In the present invention, whether or not there is an abnormality in the origin position detection based on the numerical value of the determination count value obtained by counting the change to the other logic level during the period when the origin position detection pulse becomes the logic level of the origin position detection. A plurality of abnormality levels are determined according to the numerical value of the determination count value. Thereby, it is possible to cope with each abnormality level.

  The invention according to claim 9 is the origin position detection abnormality determination method according to claim 7 or 8, wherein the abnormality determination of the origin position detection is performed by determining the abnormality level several times. The gist is to add the same abnormality count value for each abnormality level determination, set the addition value to be higher as the abnormality level is higher, and perform the abnormality determination based on the added abnormality count value. And

  In the present invention, the same abnormality count value is added every determination of each abnormality level, and the addition value at that time is set to be larger as the abnormality level is higher, and based on the added abnormality count value, Abnormality judgment is performed. As a result, each abnormality level is reflected in the abnormality determination, and only one abnormality count value is required. Therefore, management of the abnormality count value and the like are facilitated.

  According to a tenth aspect of the present invention, in the origin position detection abnormality determining method according to any one of the seventh to ninth aspects, when an abnormality occurs in the origin position detection, a notification unit is operated to operate the user. It is the gist of notifying that.

  In the present invention, when an abnormality occurs in the origin position detection, the user is notified of this, so that the user can reliably recognize the abnormal state of the apparatus.

  Therefore, according to the present invention, in a motor actuator provided with a rotation detection device that detects the origin position of the output shaft, the origin position detection method of the output shaft in the motor actuator capable of detecting the origin position with high accuracy, and Thus, it is possible to provide an abnormality determination method for detecting the origin position.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a vehicle air conditioner 1 includes a plurality of motor actuators 4 for operating various switching doors 3 for switching air passages in an air conditioning duct 2, and an air conditioner ECU 5 that controls each actuator 4. It has.

  The various switching doors 3 provided in the air conditioning duct 2 pass through the R / F door 3 a that switches the air inflow path between the outside air introduction path 6 and the inside air circulation path 7, the cold air that has passed through the evaporator 8, and the heater core 9. There are an air mix door 3b for mixing warm air and a mode switching door 3c for changing the air blowing path into the passenger compartment. Each of these various switching doors 3 is provided with a corresponding motor actuator 4 having the same configuration.

  As shown in FIG. 2, the motor actuator 4 includes a drive motor 11, a speed reduction mechanism 14 that decelerates rotation of the motor rotation shaft 12 and transmits the rotation to the output shaft 13, and a rotation position (rotation angle) of the motor rotation shaft 12. A motor shaft side rotation detecting device 15 for detecting and an output shaft side rotation detecting device 16 for detecting the origin position of the output shaft 13 are provided and housed in a case 17.

  In this embodiment, the drive motor 11 is a DC motor with a brush, and a motor rotating shaft 12 that is rotationally driven by power feeding is provided with a worm 12a. A sensor magnet 15a is fixed to the outer peripheral surface of the motor rotating shaft 12 or the worm 12a. A sensor substrate 15b is fixed to the case 17 at a position close to the sensor magnet 15a. Magnetic detection elements 15c and 15d such as a Hall element and a magnetoresistive element for detecting a magnetic field change by the sensor magnet 15a are provided on the substrate 15b. Arranged in pairs. The motor shaft side rotation detection device 15 is constituted by the sensor magnet 15a and the sensor substrate 15b having the magnetic detection elements 15c and 15d.

  And each magnetism detection element 15c, 15d in the motor shaft side rotation detector 15 detects the magnetic change accompanying rotation of the sensor magnet 15a rotating with the motor rotating shaft 12, and outputs the detection signal to the air conditioner ECU 5, respectively. Incidentally, each of the magnetic detection elements 15c and 15d outputs an output pulse as a detection signal, but is arranged so as to be shifted in the rotation direction of the motor rotating shaft 12 so that the respective output pulses are 90 ° out of phase with each other. And it outputs to air-conditioner ECU5 as A phase output pulse and B phase output pulse as shown in FIG.

  As shown in FIG. 3, a disk-shaped sensor magnet 15a is fixed to the end of the motor rotating shaft 12 opposite to the worm 12a, and the magnetic detection elements 15c and 15d are placed near the outer periphery of the magnet 15a. It is also possible to configure the motor shaft side rotation detection device 15 by arranging the mounted sensor substrate 15b.

  The reduction mechanism 14 includes a first reduction gear 14a, a second reduction gear 14b, and an output gear 14c. The worm 12a of the motor rotating shaft 12 is engaged with a first reduction gear 14a, the first reduction gear 14a is engaged with a second reduction gear 14b, and the second reduction gear 14b is engaged with an output gear 14c. That is, the rotation of the motor rotating shaft 12 is decelerated (low rotation and high torque) through the gears 14a to 14c and transmitted to the output shaft 13 provided integrally with the output gear 14c. The switching door 3 is connected to the output shaft 13, and the opening degree of the switching door 3 is changed by the rotation of the output shaft 13. The switching door 3 swings within a predetermined angle range, and the output shaft 13 that drives the switching door 3 is rotated within the predetermined angle range.

  Further, a sensor magnet 16a is fixed to one side surface of the output gear 14c at a position offset in the radial direction from the output shaft 13 which is a rotation shaft of the gear 14c. A sensor substrate 16b is fixed to the case 17 at a position close to the sensor magnet 16a, and a magnetic detection element 16c such as a Hall element or a magnetoresistive element for detecting a magnetic field change by the sensor magnet 16a is disposed on the substrate 16b. Has been. The sensor shaft 16b having the sensor magnet 16a and the magnetic detection element 16c constitutes the output shaft side rotation detection device 16.

  The magnetic detection element 16c in the output shaft side rotation detection device 16 detects a magnetic change accompanying the rotation of the sensor magnet 16a that rotates together with the output gear 14c, and outputs a detection signal to the air conditioner ECU 5. Incidentally, the magnetic detection element 16c outputs, as a detection signal, an origin position detection pulse as shown in FIGS. 4 and 5 in which only one pulse rises when the output shaft 13 is arranged at the origin position.

  The air conditioner ECU 5 receives A-phase and B-phase output pulses from a motor shaft side rotation detection device 15 provided in the motor actuator 4 and receives an origin position detection pulse from the output shaft side rotation detection device 16. The air conditioner ECU 5 counts based on both rising and falling edges of the input A-phase and B-phase output pulses, and based on the count value, the rotational position of the motor rotating shaft 12, that is, the rotating position of the output shaft 13 ( Rotation angle) is detected with a high resolution of, for example, 0.2 °. The air conditioner ECU 5 stores the count value in the memory 5a in the ECU 5 each time.

  Further, the air conditioner ECU 5 detects the rising edge of the origin position detection pulse input during, for example, normal rotation (or reverse rotation) of the output shaft 13 and the falling edge of the origin position detection pulse. The count value (Nb) at the time of detection is stored, and the count value (Na, Nb) corresponding to both stored edges is added and divided by “2”, that is, the origin position detection pulse A count value (intermediate value Nx) corresponding to the intermediate position of the pulse width (between both edges) is calculated, and this intermediate value (Nx) is recognized as the origin position of the output shaft 13. That is, although the pulse width of the origin position detection pulse is, for example, 5 °, the accuracy required for the origin position is, for example, 0.5 °. In this embodiment, the accuracy of the origin position is obtained by using the above calculation. Is set to 0.2 ° which is 0.5 ° or less.

  Here, the pulse widths of the A-phase and B-phase output pulses and the origin position detection pulse vary due to environmental variations such as temperature and power supply voltage. In particular, since the origin position detection pulse is targeted for detection of the low-speed output gear 14c, there is a concern that the origin position accuracy of the output shaft 13 is affected because the origin position detection pulse is greatly affected by fluctuations in the pulse width. However, as shown in FIG. 6, the edge positions on both sides change in the same manner, and the pulse width becomes large or small (in FIG. 6, the case where the pulse width becomes small) is shown. The position does not change greatly.

  That is, in the case of using the method of calculating the intermediate value (Nx) of the count values (Na, Nb) corresponding to both edges of the origin position detection pulse as the origin position of the output shaft 13 as in the present embodiment, The origin position detection accuracy is high.

  Then, the air conditioner ECU 5 grasps the opening degree of the switching door 3 based on the origin position and the rotational position of the output shaft 13 of the motor actuator 4 obtained in this way, and based on the opening degree of the switching door 3, the motor actuator 4 (drive motor 11) is controlled.

Next, characteristic actions and effects of the present embodiment will be described.
(1) The air conditioner ECU 5 of the present embodiment calculates a count value based on the rising edge and the falling edge of the AB phase output pulse, and the rising edge of the origin position detection pulse when the output shaft 13 rotates in one direction. An intermediate value (Nx) of the count values (Na, Nb) corresponding to each falling edge is calculated as the origin position of the output shaft 13. In other words, when an environmental change such as temperature or power supply voltage occurs, the pulse width of the origin position detection pulse increases or decreases, but the intermediate position of the pulse width does not change greatly. By calculating (detecting) the intermediate value (Nx) of the count values (Na, Nb) corresponding to each of the falling edges as the origin position of the output shaft 13, the origin position detection accuracy is less susceptible to the environmental fluctuations described above. Can be high.

  (2) Since the rotation detection device 15 of the present embodiment is configured to output an output pulse synchronized with the rotation of the motor rotation shaft 12, the origin position and rotation position (rotation angle) of the output shaft 13 are output by the output pulse. ) Can be detected with high resolution.

  (3) Since the rotation detection device 15 of the present embodiment is configured to output a pair of AB phase output pulses that are 90 ° out of phase with each other in synchronization with the rotation of the motor rotating shaft 12, The origin position and rotation position (rotation angle) of the output shaft 13 can be detected with higher resolution.

  (4) Like the motor actuator 4 of the present embodiment, the output door 13 that drives the switching door 3 that switches the air flow path in the air conditioning duct 2 of the vehicle air conditioner 1 can be used for temperature, power supply voltage, etc. Since it is disposed in an environment in which environmental fluctuations are likely to occur, the effect of applying the above-described method for calculating the origin position of the output shaft 13 to the motor actuator 4 is great.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. In the present embodiment, since only the method for detecting the origin position of the output shaft 13 is different, this portion will be mainly described.

As shown in FIG. 7, the air conditioner ECU 5 of the present embodiment detects the origin position of the output shaft 13 with high accuracy in consideration of both forward rotation and reverse rotation of the output shaft 13.
Specifically, the air conditioner ECU 5 detects the count value (Na1) when detecting the rising edge of the origin position detection pulse input during the forward rotation of the output shaft 13, and the falling edge of the origin position detection pulse. The count value (Nb1) at that time is stored, and an intermediate value (Nx1) of the count values (Na1, Nb1) corresponding to the stored both edges is calculated and stored. Even when the output shaft 13 rotates in reverse, the air conditioner ECU 5 detects the count value (Na2) when the rising edge of the input origin position detection pulse is detected and the falling edge of the origin position detection pulse. The count value (Nb2) is stored, and an intermediate value (Nx2) of the count values (Na2, Nb2) corresponding to the stored both edges is calculated and stored. The air conditioner ECU 5 recognizes the intermediate value (Nx) of the intermediate value (Nx1) of the origin position detection pulse during forward rotation and the intermediate value (Nx2) of the origin position detection pulse during reverse rotation as the origin position of the output shaft 13. Like to do.

  In the method of setting the intermediate value (Nx) calculated in this way as the origin position of the output shaft 13, even if the pulse width is large or small due to environmental fluctuations such as temperature and power supply voltage, as in the first embodiment, Since the influence on the intermediate value (Nx) is small, the detection accuracy of the origin position is high.

  In addition, the edge of the origin position detection pulse at the time of forward rotation and reverse rotation may shift due to the assembly error of the output shaft side rotation detection device 16 or the motor actuator 4, and the calculation method as in this embodiment is performed. If used, the influence can be eliminated, and the detection accuracy of the origin position can be further increased.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. In the present embodiment, since only the method for detecting the origin position of the output shaft 13 is different, this portion will be mainly described.

  As shown in FIG. 8, the air conditioner ECU 5 according to the present embodiment determines the origin position of the output shaft 13 in consideration of both forward rotation and reverse rotation of the output shaft 13, as in the second embodiment. It is detected with high accuracy.

  Specifically, the air conditioner ECU 5 stores the count value (Na1) when the rising edge of the origin position detection pulse input during the forward rotation of the output shaft 13 is detected, and also during the reverse rotation of the output shaft 13. The count value (Na2) when the rising edge of the input origin position detection pulse is detected is stored. The air conditioner ECU 5 recognizes the intermediate value (Nx) of the count values (Na1, Na2) corresponding to the stored both edges as the origin position of the output shaft 13.

  Even in the method of setting the intermediate value (Nx) calculated in this way as the origin position of the output shaft 13, as in the first embodiment, even if the pulse width is increased or decreased due to environmental fluctuations such as temperature and power supply voltage. Since the influence on the intermediate value (Nx) is small, the detection accuracy of the origin position is high.

  In addition, the edge of the origin position detection pulse at the time of forward rotation and reverse rotation may shift due to the assembly error of the output shaft side rotation detection device 16 or the motor actuator 4, and the calculation method as in this embodiment is performed. Even if it is used, the influence can be eliminated as in the second embodiment, and the detection accuracy of the origin position can be further improved.

Further, in the present embodiment, the number of times of calculating the intermediate value and the count value used (stored) when calculating the intermediate value can be reduced as compared with the second embodiment.
(Fourth embodiment)
Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. In the present embodiment, since only the method for detecting the origin position of the output shaft 13 is different, this portion will be mainly described.

  As shown in FIG. 9, the air conditioner ECU 5 according to the present embodiment takes into account both the forward rotation and the reverse rotation of the output shaft 13 in the same manner as in the second and third embodiments. The origin position is detected with high accuracy.

  Specifically, the air conditioner ECU 5 stores the count value (Nb1) when the falling edge of the origin position detection pulse input during the forward rotation of the output shaft 13 is detected and also during the reverse rotation of the output shaft 13. Also, the count value (Nb2) when the falling edge of the input origin position detection pulse is detected is stored. The air conditioner ECU 5 recognizes the intermediate value (Nx) of the count values (Nb1, Nb2) corresponding to both stored edges as the origin position of the output shaft 13. Even if it does in this way, the effect similar to the said 3rd Embodiment can be acquired.

(Fifth embodiment)
Hereinafter, a fifth embodiment of the present invention will be described with reference to the drawings. In the present embodiment, it is configured to determine whether or not an abnormality has occurred in the output shaft side rotation detection device 16 that detects the position of the origin of the output shaft 13 and detects the position. Below, it demonstrates focusing on the part.

  The origin position detection pulse output from the magnetic detection element 16c of the output shaft side rotation detection device 16 has a substantially constant pulse width with respect to the rotation angle of the output shaft 13 in a normal state. On the other hand, for example, when an abnormality occurs in the magnetic detection element 16c or the like, the pulse width is increased or decreased. When such position detection is abnormal, there is a concern that the control of the motor actuator 4 (drive motor 11) of the air conditioner ECU 5 may be affected and malfunctioned. Considering this, the air conditioner ECU 5 of the present embodiment is provided with an abnormality detection unit 5b as shown by a broken line in FIG.

  In the air conditioner ECU 5 of the present embodiment, as shown in FIG. 10, a lower determination value Nwmin1 and an upper determination value Nwmax1 for determining whether or not the pulse width Nw of the origin position detection pulse is abnormal are stored in the memory 5a in advance. ing. Further, in the air conditioner ECU 5 of the present embodiment, a lower limit value Nwmin2 that is smaller by a predetermined value than the lower determination value Nwmin1 as shown in FIG. 11, and a predetermined value that is higher than the upper determination value Nwmax1 as shown in FIG. The upper limit value Nwmax2 larger by the value is stored in the memory 5a. The abnormality detection unit 5b determines whether an abnormality has occurred in the detection of the origin position based on the lower determination value Nwmin1, the lower limit value Nwmin2, the upper determination value Nwmax1, and the upper limit value Nwmax2.

  First, as shown in FIG. 10, when the pulse width Nw of the origin position detection pulse is not less than the lower determination value Nwmin1 and not more than the upper determination value Nwmax1 (Nwmin1 ≦ Nw ≦ Nwmax1), the abnormality detection unit 5b detects the origin position. When the pulse width Nw of the pulse is within the normal range, it is determined that the output shaft side rotation detection device 16 such as the magnetic detection element 16c is in a normal state. The air conditioner ECU 5 continues normal control of the motor actuator 4 based on this determination.

  On the other hand, as shown in FIG. 11A, when the pulse width Nw of the origin position detection pulse is less than the lower determination value Nwmin1 and becomes equal to or greater than the lower limit value Nwmin2 (Nwmin2 ≦ Nw <Nwmin1), the abnormality detection unit 5b It is determined that the side rotation detection device 16 is in an abnormal state of abnormal level 1. This abnormality level 1 is set to a relatively minor abnormality level that can estimate the rotational position of the output shaft 13 by the origin position detection pulse. When the abnormality level 1 is detected, for example, a plurality of times in succession by the abnormality detection unit 5b (it can be detected once), the air conditioner ECU 5 can control the motor actuator 4 even at the estimated position of the output shaft 13. Switch to the limited control mode.

  As shown in FIG. 11B, when the pulse width Nw of the origin position detection pulse becomes less than the lower limit value Nwmin2 (Nw <Nwmin2), the abnormality detection unit 5b indicates that the output shaft side rotation detection device 16 has an abnormality of abnormality level 2. It is determined that a state has been reached. This abnormality level 2 is set to a severe abnormality level that makes it impossible to detect the rotational position of the output shaft 13 based on the above estimation. When the abnormality level 2 is detected, for example, continuously a plurality of times by the abnormality detection unit 5b (a single detection is possible), the air conditioner ECU 5 stops the control of the motor actuator 4.

  When the abnormality detection unit 5b detects abnormality level 1 or abnormality level 2, the air conditioner ECU 5 activates a warning device 10 such as a warning lamp indicated by a broken line in FIG. It is configured to notify the user that the above has occurred. In this case, the abnormality level 1 and the abnormality level 2 may be the same warning or may be different depending on the abnormality level. The warning device 10 can be omitted.

  As shown in FIG. 12A, when the pulse width Nw of the origin position detection pulse exceeds the upper determination value Nwmax1 and becomes the upper limit value Nwmax2 or less (Nwmax1 <Nw ≦ Nwmax2), the abnormality detection unit 5b rotates the output shaft side. It is determined that the detection device 16 has entered a minor abnormal state with an abnormal level 1. When this abnormal level 1 is detected, for example, a plurality of times in succession, the air conditioner ECU 5 switches the control of the motor actuator 4 to the minimum control mode and operates the warning device 10 to indicate that an abnormal state has occurred. Informs the user.

  As shown in FIG. 12 (b), when the pulse width Nw of the origin position detection pulse exceeds the upper limit value Nwmax2 (Nw <Nwmax2), the abnormality detection unit 5b indicates that the output shaft side rotation detection device 16 has a severity of abnormality level 2. It is determined that the abnormal state has been reached. For example, when the abnormal level 2 is continuously detected a plurality of times, the air conditioner ECU 5 stops the control of the motor actuator 4 and operates the warning device 10 to notify the user that an abnormal state has occurred. To do.

  That is, as in this embodiment, a plurality of abnormality determination values (lower determination value Nwmin1, lower limit value Nwmin2, upper determination value Nwmax1 and upper limit value Nwmax2) to be compared with the pulse width Nw of the origin position detection pulse are set and the abnormality level By making a plurality of determinations, it is possible to take measures according to each abnormality level. In addition, when an abnormality occurs in the origin position detection, the warning device 10 notifies the user to that effect, so that the output shaft side rotation detection device 16, and thus the motor actuator 4 including the rotation detection device 16 and the vehicle air conditioning. It is possible to make the user surely recognize the abnormal state of the device 1.

  In this embodiment, the abnormal level 1 and the abnormal level 2 are separately grasped. However, for example, “1” is added to the abnormal count value based on the determination of the abnormal level 1 to determine the abnormal level 2. Based on the comparison between the abnormality count value and a preset abnormality determination value, for example, whether the abnormality of the output shaft side rotation detection device 16 is a minor abnormality or a serious abnormality. May be determined. In this way, since only one abnormality count value is required while reflecting each abnormality level in the abnormality determination, it is easy to manage the abnormality count value. The added value is not limited to “1” or “3”, and may be changed as appropriate as long as the added value at the abnormal level 2 is larger than the added value at the abnormal level 1.

(Sixth embodiment)
Hereinafter, a sixth embodiment of the present invention will be described with reference to the drawings. In the present embodiment, as in the fifth embodiment, there is provided means for determining whether or not an abnormality has occurred in the output shaft side rotation detection device 16. Below, it demonstrates focusing on the part.

  The origin position detection pulse output from the magnetic detection element 16c of the output shaft side rotation detection device 16 has a waveform that rises to H level only once in the operating range of the output shaft 13 in a normal state, and a rising edge and a falling edge respectively. One (see FIG. 10). On the other hand, when an abnormality occurs in the magnetic detection element 16c, for example, as shown in FIG. 13, a so-called crack that falls to the L level once or a plurality of times occurs during the period of rising to the H level in the normal state. When such position detection is abnormal, as in the fifth embodiment, the control of the motor actuator 4 (drive motor 11) of the air conditioner ECU 5 is affected, and there is a concern about malfunction.

  In consideration of this, the abnormality detection unit 5b of the present embodiment provided in the air conditioner ECU 5 sets the crack count value (determination count value) to “1” every time the rising edge and the falling edge of the origin position detection pulse are detected. "to add. Since there is no crack at normal time, there is one rising edge and one falling edge, and the crack count value is “2”. Based on the detection that the crack count value is “2”, the abnormality detection unit 5b has the pulse width Nw of the origin position detection pulse within the normal range, and the output shaft side rotation detection device 16 such as the magnetic detection element 16c is normal. It is determined that the state is not correct. The air conditioner ECU 5 continues normal control of the motor actuator 4 based on this determination.

  On the other hand, when a crack occurs during the period when the origin position detection pulse is normally H level, the rising edge and the falling edge are two or more, and the crack count value is “4” or more. Therefore, when the crack count value is “4” or more, the abnormality detection unit 5b determines that some abnormality has occurred in the output shaft side rotation detection device 16.

  In this case, as shown in FIG. 13A, for example, when there are less than three cracks, that is, when the crack count value is less than the preset abnormality determination value “8”, the abnormality detection unit 5b rotates the output shaft side. It is determined that the detection device 16 has entered a minor abnormal state with an abnormal level 1. When this abnormal level 1 is detected a plurality of times continuously (for example, it can be detected once), the air conditioner ECU 5 controls the motor actuator 4 in the minimum control mode as in the fifth embodiment. And the warning device 10 is activated to notify the user that an abnormal condition has occurred.

  As shown in FIG. 13B, for example, when there are three or more cracks, that is, when the crack count value is equal to or greater than a preset abnormality determination value “8”, the abnormality detection unit 5 b includes the output shaft side rotation detection device 16. Is determined to be in a severe abnormal state of abnormal level 2. When the abnormal level 2 is detected, for example, a plurality of times in succession (can be detected once), the air conditioner ECU 5 stops the control of the motor actuator 4 and warns, as in the fifth embodiment. The device 10 is operated to notify the user that an abnormal state has occurred.

  Incidentally, the air conditioner ECU 5 of the present embodiment detects the above-described origin position (intermediate value Nx) and the entire pulse width Nw including the cracked portion based on the outermost edge of the origin position detection pulse. ing. By detecting the pulse width Nw, the present embodiment can be combined with the fifth embodiment.

  Then, as in the present embodiment, a crack occurs in the origin position detection pulse, and a plurality of abnormal levels are determined according to the numerical value of the crack count value, so that a countermeasure corresponding to each abnormal level can be taken. Also in the present embodiment, the warning device 10 allows the user to surely recognize the abnormal state of the output shaft side rotation detection device 16 and thus the motor actuator 4 including the rotation detection device 16 and the vehicle air conditioner 1. it can.

  Similarly, in the present embodiment, “1” is added to the abnormal count value based on the determination of the abnormal level 1, and “3” is added to the abnormal count value based on the determination of the abnormal level 2, for example. If it is determined whether the abnormality of the output shaft side rotation detection device 16 is minor or severe based on a comparison between the abnormality count value and a preset abnormality determination value, each abnormality level is reflected in the abnormality determination. However, since only one abnormal count value is required, it is easy to manage the abnormal count value.

The embodiment of the present invention may be modified as follows.
In each of the above embodiments, the rotation detection device 15 is configured to output an AB-phase output pulse, but may be configured to output only one output pulse.

  In each of the above embodiments, the detection target of the rotation detection device 15 is the motor rotation shaft 12, but the first reduction gear 14a and the second reduction gear 14b in the preceding stage of the output gear 14c may be the detection target.

  In each of the above embodiments, the detection object of the rotation detection device 16 is the output gear 14c, and the sensor magnet 16a, which is the detection object, is disposed on the output gear 14c, but the output shaft 13 is the detection object. An object to be detected may be disposed on the surface.

  In each of the above embodiments, the rotation detection devices 15 and 16 use magnetic sensors (magnetic detection elements 15c, 15d, and 16c), but mechanical contact sensors and optical sensors are used instead of the magnetic sensors. Also good. In this case, the object to be detected is appropriately changed from the sensor magnets 15a and 16a according to the sensor to be used.

In each of the above embodiments, a brushed DC motor is used as the drive motor 11, but other motors such as a stepping motor or a brushless motor may also be used.
In each of the above embodiments, the AB phase output pulse and the origin position detection pulse are output to the air conditioner ECU 5, and the ECU 5 calculates the origin position of the output shaft 13. An IC may be mounted, and the origin position of the output shaft 13 may be calculated by the control IC.

It is a schematic block diagram of the vehicle air conditioner in each embodiment. It is a schematic block diagram of a motor actuator. It is a schematic block diagram for demonstrating the modification of a motor actuator. It is a wave form diagram for explaining various pulse signals. It is a figure for demonstrating the calculation method of the origin position in 1st Embodiment. It is a figure for demonstrating the calculation method of the origin position in 1st Embodiment. It is a figure for demonstrating the calculation method of the origin position in 2nd Embodiment. It is a figure for demonstrating the calculation method of the origin position in 3rd Embodiment. It is a figure for demonstrating the calculation method of the origin position in 4th Embodiment. It is a figure for demonstrating abnormality determination of the origin position detection in 5th Embodiment. It is a figure for demonstrating abnormality determination of the origin position detection in 5th Embodiment. It is a figure for demonstrating abnormality determination of the origin position detection in 5th Embodiment. It is a figure for demonstrating abnormality determination of the origin position detection in 6th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle air conditioner, 2 ... Air conditioning duct, 3 ... Switching door, 4 ... Motor actuator, 10 ... Warning device as a notification means, 11 ... Drive motor, 12 ... Motor rotating shaft, 13 ... Output shaft, 14 ... Deceleration Mechanism: 14a: First reduction gear as a reduction gear, 14b: Second reduction gear as a reduction gear, 14c: Output gear, 15: Motor shaft side rotation detection device as a second rotation detection device, 16: First rotation Output shaft side rotation detection device as a detection device, Na, Nb, Na1, Nb1, Na2, Nb2 ... count value, Nx ... intermediate value, Nx1 ... first intermediate value, Nx2 ... second intermediate value, Nw ... pulse width, Nwmin1: lower determination value as an abnormality determination value, Nwmin2: lower limit value as an abnormality determination value, Nwmax1: upper determination value as an abnormality determination value, Nwmax2: upper limit value as an abnormality determination value.

Claims (10)

A drive motor for rotationally driving the motor rotation shaft;
A speed reduction mechanism that includes a plurality of reduction gears including an output gear having an output shaft, and that reduces the rotation of the motor rotation shaft and transmits it to the output shaft;
A first rotation detection device for detecting either the output gear or the output shaft as an object of detection, and outputting an origin position detection pulse based on the arrangement of the origin position of the output shaft;
An output shaft in a motor actuator comprising: a second rotation detection device that outputs either an output pulse synchronized with the rotation of the detection target, with either the motor rotation shaft or the reduction gear preceding the output gear as a detection target The origin position detection method of
Counting based on at least one of the rising edge and falling edge of the output pulse to calculate a count value,
In the motor actuator, the intermediate value of the count value corresponding to each of the rising edge and the falling edge of the origin position detection pulse when the output shaft rotates in one direction is calculated as the origin position of the output shaft. How to detect the origin position of the output shaft. A drive motor for rotationally driving the motor rotation shaft;
A speed reduction mechanism that includes a plurality of reduction gears including an output gear having an output shaft, and that reduces the rotation of the motor rotation shaft and transmits it to the output shaft;
A first rotation detection device for detecting either the output gear or the output shaft as an object of detection, and outputting an origin position detection pulse based on the arrangement of the origin position of the output shaft;
An output shaft in a motor actuator comprising: a second rotation detection device that outputs either an output pulse synchronized with the rotation of the detection target, with either the motor rotation shaft or the reduction gear preceding the output gear as a detection target The origin position detection method of
Counting based on at least one of the rising edge and falling edge of the output pulse to calculate a count value,
A first intermediate value of the count value corresponding to each of a rising edge and a falling edge of the origin position detection pulse during forward rotation of the output shaft is calculated, and the origin position detection pulse during reverse rotation of the output shaft A second intermediate value of the count value corresponding to each of the rising edge and the falling edge of the output axis is calculated, and a further intermediate value of the calculated first and second intermediate values is calculated as the origin position of the output shaft. A method for detecting the origin position of the output shaft in the motor actuator. A drive motor for rotationally driving the motor rotation shaft;
A speed reduction mechanism that includes a plurality of reduction gears including an output gear having an output shaft, and that reduces the rotation of the motor rotation shaft and transmits it to the output shaft;
A first rotation detection device for detecting either the output gear or the output shaft as an object of detection, and outputting an origin position detection pulse based on the arrangement of the origin position of the output shaft;
An output shaft in a motor actuator comprising: a second rotation detection device that outputs either an output pulse synchronized with the rotation of the detection target, with either the motor rotation shaft or the reduction gear preceding the output gear as a detection target The origin position detection method of
Counting based on at least one of the rising edge and falling edge of the output pulse to calculate a count value,
An intermediate value of the count value corresponding to each rising edge of the origin position detection pulse during forward rotation and reverse rotation of the output shaft, or a rise of the origin position detection pulse during forward rotation and reverse rotation of the output shaft. A method for detecting an origin position of an output shaft in a motor actuator, wherein an intermediate value of the count values corresponding to each of falling edges is calculated as an origin position of the output shaft. In the method for detecting the origin position of the output shaft in the motor actuator according to any one of claims 1 to 3,
The method of detecting the origin position of an output shaft in a motor actuator, wherein the second rotation detection device outputs the output pulse synchronized with the rotation of the motor rotation shaft with the motor rotation shaft as a detection target. In the method for detecting the origin position of the output shaft in the motor actuator according to any one of claims 1 to 4,
The method of detecting the origin position of an output shaft in a motor actuator, wherein the second rotation detection device outputs a pair of output pulses whose phases are shifted by 90 ° in synchronization with the rotation of the detection target. In the method for detecting the origin position of the output shaft in the motor actuator according to any one of claims 1 to 5,
The motor actuator drives the switching door which switches the ventilation path | route in the air-conditioning duct of a vehicle air conditioner with the output shaft, The origin position detection method of the output shaft in a motor actuator characterized by the above-mentioned. The origin position detection method for determining the origin position of the output shaft in the motor actuator according to any one of claims 1 to 6, wherein an abnormality is detected in the origin position detection. ,
The pulse width of the origin position detection pulse is detected, and a plurality of abnormality determination values serving as a reference for determining whether or not abnormality has occurred in the origin position detection based on the detected pulse width are set on the upper side or the lower side. An origin position detection abnormality determination method comprising: determining a plurality of abnormality levels based on a comparison between each abnormality determination value and the pulse width. The origin position detection method for determining the origin position of the output shaft in the motor actuator according to any one of claims 1 to 6, wherein an abnormality is detected in the origin position detection. ,
During the period in which the origin position detection pulse is at the origin position detection logic level, a change to another logic level is counted to determine whether or not an origin position detection abnormality has occurred. And determining a plurality of abnormality levels according to the numerical value of the determination count value. In the abnormality determination method of origin position detection according to claim 7 or 8,
The determination of the origin position is performed by determining the abnormality level several times, and the same abnormality count value is added each time the abnormality level is determined, and the added value is set to a high abnormality level. The origin position detection abnormality determination method, wherein the abnormality determination is performed based on the added abnormality count value. In the abnormality determination method of origin position detection according to any one of claims 7 to 9,
An abnormality determination method for detecting an origin position, wherein when an abnormality occurs in the origin position detection, a notification means is operated to notify the user to that effect.

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