WO2013093983A1

WO2013093983A1 - Brushless motor device, motor control device, and origin learning method

Info

Publication number: WO2013093983A1
Application number: PCT/JP2011/007219
Authority: WO
Inventors: 友邦加藤; 綿貫　晴夫
Original assignee: 三菱電機株式会社
Priority date: 2011-12-22
Filing date: 2011-12-22
Publication date: 2013-06-27

Abstract

The brushless motor device is equipped with: a position-detecting Hall IC (17a) for detecting a rotational position of a rotor (11); an origin-learning Hall IC (17b) for detecting a predetermined rotational position during one rotation of the rotor (11); and a control unit (31) that, on a condition that the brushless motor device (1) is assembled to a member to be driven (2) in such a manner that a motor shaft (10) moves to a position so as to come in contact with a rod (20) at the predetermined rotational position during the one rotation of the rotor (11), determines the position where the rotation of the rotor (11) becomes restricted as the motor shaft (10) comes in contact with the rod (20) on the basis of an output pattern of the position-detecting Hall IC (17a), which changes with the rotation of the rotor (11) when the motor shaft (10) is moved by a predetermined amount at a time, and an output pattern of the origin-learning Hall IC (17b), and learns said position as an origin position.

Description

Brushless motor device, motor control device, and origin learning method

The present invention controls the drive of a brushless motor device used as a drive source for an exhaust gas control actuator such as an EGR (Exhaust Gas Recirculation) valve or a VG (Variable Geometric) turbo actuator for a vehicle. The present invention relates to an origin learning method for a motor control device and a brushless motor device.

In the conventional brushless motor, the relative rotational position of the rotor relative to the three-phase (U, V, W) stator coil is determined by sensing the magnetic flux from the position detection magnet provided on the rotor with the position detection Hall IC. It is detected (see, for example, Patent Document 1).
The three position detection Hall ICs output high-level “H” and low-level “L” electrical signals in response to switching of the rotation direction of the magnetic poles of the position detection magnet, respectively, while the rotor rotates once. In addition, a predetermined output pattern corresponding to three phases (U, V, W) is repeated.

Also, in a brushless motor used for an EGR valve or the like, one end of the motor shaft is screwed into a female screw provided in the rotor, and the motor shaft is pushed out in the axial direction and pulled in as the rotor rotates. For example, when a brushless motor is used as an actuator of an EGR valve, the valve is opened and closed by interlocking the rod connected to the valve with the movement of the motor shaft.

International Publication WO2007 / 148480 Specification

In the conventional brushless motor device, the stopper formed at the motor shaft retract limit position in the rotor is used as a temporary origin position, and the position where the motor shaft pushed out from this position contacts the rod is the origin of the actuator, that is, the motor shaft. This is the driving origin. In a vehicle EGR system or the like, this origin learning process is a process that is performed at the time of system operation or termination. Therefore, in order to perform system operation or termination quickly, it is desired to shorten the origin learning time. .

Also, every time the origin learning process is performed, the position of the stopper may change due to wear or the like because the position is specified by moving the motor shaft until it contacts the stopper. In this case, the distance from the end surface of the motor shaft to the end surface of the rod is increased, and the movement amount of the motor shaft in the origin learning process is increased, and there is a concern that the origin learning process may take a long time.

In the conventional brushless motor device, as shown in Patent Document 1, the relative rotational position of the rotor with respect to the stator coil can be detected by the position detection Hall IC, but from the output pattern of the position detection Hall IC. The position of the motor shaft in the axial direction cannot be accurately detected.

The present invention has been made to solve the above-described problems, and is provided with a brushless motor device capable of shortening the learning time of the drive origin, a motor control device for controlling the drive of the brushless motor device, and a brushless motor device. The purpose is to obtain an origin learning method.

The brushless motor device according to the present invention is a brushless motor device in which the motor shaft moves in the axial direction as the rotor rotates, and drives the rod of the driven member arranged coaxially with the motor shaft. A position detection sensor unit for detecting, an origin learning sensor unit for detecting a predetermined rotation position during one rotation of the rotor, and a motor shaft moving position at a predetermined rotation position during one rotation of the rotor. On the condition that the brushless motor device is assembled to the driven member so as to come into contact, the output pattern of the position detecting sensor unit that switches with the rotation of the rotor when the motor shaft is moved by a predetermined amount, and From the output pattern of the origin learning sensor unit, the motor shaft contacts the rod and the rotation of the rotor is restricted. Determine the position, and a control unit for learning the position as the origin position.

According to the present invention, there is an effect that the learning time of the drive origin can be shortened.

It is a figure which shows the structure of the brushless motor apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the magnet, Hall IC for position detection, and Hall IC for origin learning concerning this invention. It is a block diagram which shows the structure of the motor control apparatus which controls the drive of the brushless motor apparatus which concerns on Embodiment 1. FIG. It is a figure which shows the output pattern of Hall IC for position detection, and Hall IC for origin learning. It is a figure which shows the structure of the EGR valve | bulb using the brushless motor apparatus which concerns on Embodiment 1. FIG. 4 is a flowchart showing origin learning processing by the brushless motor device according to the first embodiment.

Hereinafter, in order to describe the present invention in more detail, modes for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
1 is a diagram showing a configuration of a brushless motor apparatus according to Embodiment 1 of the present invention. The brushless motor apparatus 1 shown in FIG. 1 is used as an actuator that drives the rod 20 of the driven member 2 that is arranged coaxially with the motor shaft 10 when the motor shaft 10 moves in the axial direction by the rotation of the rotor 11.
The motor shaft 10 has a male screw formed at one end thereof and is screwed into a female screw formed on the rotor 11. The screw is formed so that the movement amount of the motor shaft 10 per rotation of the rotor 11 becomes a predetermined value.
The brushless motor device 1 according to the present invention is driven so that the distance A between the end surface of the motor shaft 10 and the end surface of the rod 20 is shorter than the moving distance of the motor shaft 10 during one rotation of the rotor 11. It is assembled to the housing 21 of the member 2. That is, the motor shaft 10 contacts the end surface of the rod 20 while the rotor 11 rotates once.

The rotor 11 is inserted into the hollow portion of the stator 13 in the case 12 and is rotatably supported by the bearing 14. In addition, a disk-like magnet 15 is fixed to the rotor 11 on a surface orthogonal to the rotation axis. The magnet 15 is a disk-shaped permanent magnet provided on a surface orthogonal to the rotation axis of the rotor 11, and has a position detection magnetic pole portion 15a and an origin learning magnetic pole portion 15b. As will be described later with reference to FIG. 2, the position detecting magnetic pole portion 15a is a magnetic pole portion formed by alternately arranging different magnetic poles around the rotation axis of the rotor 11, and the origin learning magnetic pole portion 15b is used for position detection. The magnetic pole part is formed by extending one of the adjacent magnetic pole pairs of the magnetic pole part 15a in the outer edge direction.

The position detection Hall IC 17a and the origin learning Hall IC 17b are mounted on the printed circuit board 16. The position detection Hall IC 17a is disposed to face the position detection magnetic pole portion 15a, detects the magnetic flux of the position detection magnetic pole portion 15a of the magnet 15 rotating together with the rotor 11, and rotates the rotor 11 corresponding to the magnetic pole. A signal indicating the position is output. The origin learning hall IC 17b is arranged on the same surface (printed circuit board 16) as the position detection hall IC 17a with a pitch diameter different from that of the position detection hall IC 17a, and the origin learning magnetic pole part of the magnet 15 that rotates together with the rotor 11 is provided. Only the magnetic flux 15b is detected, and a signal indicating a predetermined rotational position (a position where the origin learning Hall IC 17b is located on the origin learning magnetic pole portion 15b) while the rotor 11 corresponding to the magnetic pole rotates once is output. .

When the coil wound around the stator 13 is energized, the stator 13 polarized by a plurality of magnetic poles is NS magnetized. Further, on the outer peripheral surface of the rotor 11, a rotor rotating magnet magnetized NS so that the magnetic poles are switched in the rotation direction is provided. When the stator 13 is NS magnetized, the rotor 11 is rotated by the electromagnetic action of the stator 13 and the rotor rotating magnet. Further, the motor shaft 10 moves along the axial direction by the rotation of the rotor 11. At this time, according to the rotation direction of the rotor 11, the motor shaft 10 moves in a direction (for example, forward rotation) pulled into the motor side and a direction (for example, reverse rotation) pushed out from the motor side.

As shown in FIG. 1, the motor shaft 10 is formed so that the diameter of the portion that protrudes and protrudes from the motor by the rotation of the rotor 11 is larger than the diameter of the male screw portion that is screwed into the female screw of the rotor 11. 11 is formed with a stopper 11a that abuts against the stepped surface of the motor shaft 10 having a different diameter. The stopper 11a defines a movement upper limit position in the pull-in direction of the motor shaft 10, and the stopper 11a abuts on the stepped surface of the motor shaft 10 moved in the pull-in direction to restrict further movement.

Here, the conventional origin learning process will be briefly described.
As described above, since the stopper 11a is provided at a predetermined position in the axial direction of the motor shaft 10, the origin position is learned on the basis of the position of the stopper 11a.
In this origin learning process, first, (1) the motor shaft 10 is moved in the retracting direction and brought into contact with the stopper 11a. Next, (2) using the position of the stopper 11a as the starting point for the origin learning, the motor shaft 10 is moved in this direction from this position. Thereafter, (3) learning is performed with the position where the motor shaft 10 is in contact with the end face of the rod 20 as the origin.
In the above (2), even if the motor shaft 10 contacts the rod 20, the rod 20 is driven with a drive duty ratio that does not move.

In the conventional origin learning process, as shown in the above (1) to (3), after the motor shaft 10 is pulled into the stopper 11a, it is pushed out until it comes into contact with the end face of the rod 20. As described above, since the moving distance by the pull-in and push-out is long, the EGR valve device of the vehicle requires a time of several seconds to complete the origin learning. For example, in the case of an engine system that performs origin learning when the engine key is turned on, the EGR valve device does not operate until the origin learning is completed. In the case of an engine system that performs origin learning when the engine key is turned off, origin learning is not performed. You will not be able to shut down the system until it is complete.

Conventionally, since the motor shaft 10 contacts the stopper 11a every time the origin learning is performed, there is a possibility that the stopper 11a is worn and the starting position of the origin learning changes.
For example, if the origin learning start position shifts in the pull-in direction due to wear of the stopper 11a, the motor shaft 10 does not contact the rod 20 even if the motor shaft 10 is pushed out from the position of the stopper 11a with the initial stroke. It takes more time to complete the origin learning.

Therefore, the origin learning process according to the present invention determines the position where the motor shaft 10 contacts the rod 20 from the output pattern of the position detection Hall IC 17a and the output pattern of the origin learning Hall IC 17b. As a result, the amount of movement of the motor shaft 10 required for origin learning can be significantly reduced without using a mechanical stopper that may cause a change over time due to wear or the like. Can be shortened.

FIG. 2 is a diagram showing a magnet, a position detection Hall IC, and an origin learning Hall IC according to the present invention. Since the magnet 15 illustrated in FIG. 2 has “8” poles, the stator 13 has “9” slots and the rotor 11 has “8” poles. The magnet 15 corresponds to one pole of the rotor 11 with a pair of NS poles.
The position detection Hall ICs 17a-1 to 17a-3 are provided corresponding to the three phases (U, V, W) of the stator 13, and are provided for the position detection magnetic pole portion 15a in which the magnetic pole is switched in the rotation direction of the magnet 15. A magnetic level signal corresponding to the polarity is output by detecting the magnetic flux.

Further, in the present invention, as shown in FIG. 2, one of the adjacent magnetic pole pairs of the position detecting magnetic pole portion 15 a is extended in the direction of the outer edge of the magnet 15 as the origin learning magnetic pole portion 15 b.
The origin learning Hall IC 17b is provided corresponding to the origin learning magnetic pole portion 17b on the outer edge of the magnet 15, and the magnetic flux of the origin learning magnetic pole portion 15b is generated while the magnet 15 rotates once, that is, the rotor 11 rotates once. A signal having a logic level corresponding to the polarity is detected and output.

In the origin learning process according to the present invention, the distance A between the end surface of the motor shaft 10 and the end surface of the rod 20 is shorter than the moving distance of the motor shaft 10 during one rotation of the rotor 11, and the origin learning hole is used. It is a precondition that the motor shaft 10 contacts the end face of the rod 20 at the timing when the IC 17b is positioned on the origin learning magnetic pole portion 15b.
That is, the brushless motor device 1 according to the present invention adjusts the moving amount of the motor shaft 10 by adjusting the male screw of the motor shaft 10 and the female screw of the rotor 11, and sets the rotational phase of the magnet 15 to the position of the origin learning hole IC 17b. In addition, the housing of the driven member 2 is moved so that the motor shaft 10 moves from the vicinity of the end face of the rod 20 to the position where the motor shaft 10 comes into contact with the origin learning Hall IC 17b at a position facing the origin learning magnetic pole portion 15b. 21 is assembled.

FIG. 3 is a block diagram illustrating a configuration of a motor control device that controls driving of the brushless motor device according to the first embodiment. A motor control device 3 shown in FIG. 3 is a device that drives and controls the brushless motor device 1 and includes an interface 30 with a Hall IC, a control unit 31, and a drive circuit 32 as main components.
As described above, the brushless motor device 1 has a stator 13 around which windings of U-phase, V-phase, and W-phase are wound, and is located in the vicinity of the stator 13, maintains a magnetic coupling relationship, and is rotatable. , The rotor 11 supported by the position, the position detection Hall ICs 17a-1 to 17a-3 for detecting the rotational position (magnetic pole position) of the rotor 11, and the origin learning Hall IC 17b for detecting the magnetic flux of the magnetic pole part for origin learning. is set up. These Hall ICs 17a-1 to 17a-3, 17b are composed of an integrated circuit (IC) in which Hall elements are incorporated, and detect the magnetic pole of the magnet 15 (see FIG. 1) that rotates integrally with the rotor 11. And outputs a signal corresponding to the polarity of the magnetic pole.

The interface (hereinafter referred to as I / F) 30 is provided with a Hall IC terminal (U), a Hall IC terminal (V), a Hall IC terminal (W), and an origin learning Hall IC terminal.
The I / F 30 receives the rotational position signal of the position detection Hall IC 17a-1 via the Hall IC terminal (U), performs a predetermined amplification process, and outputs the signal to the control unit 31.
Further, the I / F 30 receives the rotational position signal of the position detection Hall IC 17a-2 via the Hall IC terminal (V), performs a predetermined amplification process, and outputs the signal to the control unit 31.
The I / F 30 receives the rotation position signal of the position detection Hall IC 17a-3 via the Hall IC terminal (W), performs a predetermined amplification process, and outputs the signal to the control unit 31.
Further, in the I / F 30 according to the present invention, the signal of the origin learning Hall IC 17b is input via the origin learning Hall IC terminal, and is subjected to predetermined amplification processing and the like and is output to the control unit 31.

The control unit 31 is composed of an arithmetic processing circuit such as a microcomputer, and is based on intermittent rotation angles of the rotor 11 indicated by the rotation position signals of the position detection Hall ICs 17a-1 to 17a-3 input via the I / F 30. The continuous rotation angle of the rotor 11 is calculated. Then, from the calculated rotation angle, a PWM (Pulse Width Modulation) control signal indicating a drive duty ratio is generated and applied to the drive circuit 32.
In addition, the control unit 31 performs origin learning in which the output level is switched only once until the rotor 11 makes one rotation until the output pattern of the position detection Hall ICs 17a-1 to 17a-3 input via the I / F 30. From the output pattern of the hall IC 17b, a PWM control signal is output to the drive circuit 32 according to an origin learning algorithm which will be described later with reference to FIG.

The drive circuit 32 energizes the windings of the stator 13 via the motor terminal (U), the motor terminal (V), and the motor terminal (W) at a predetermined cycle according to the PWM control signal. As a result, a sinusoidal current having a magnitude corresponding to the continuous rotation angle flows through the winding of the stator 13, and the rotor 11 can be efficiently and smoothly rotated.
Further, the drive circuit 32 energizes the windings of the stator 13 in accordance with the PWM control signal in accordance with the origin learning algorithm input from the control unit 31 to rotate the rotor 11 and rotate the motor shaft 10 in unit rotation of the rotor 11. It is moved every predetermined amount of movement according to the angle.
In the origin learning process, the PWM control signal from the control unit 31 drives the rod 20 with a drive duty ratio that does not move the rod 20 even when the motor shaft 10 contacts the end of the rod 20. That is, by pressing against the rod 20, the movement of the motor shaft 10 in the axial direction stops, and the rotation of the rotor 11 also stops.

As an aspect of the motor control device 3 according to the first embodiment, for example, it is mounted as one function of an electronic control unit (ECU) of a vehicle, and a hole is formed between it and the brushless motor device 1 via a wire harness. There is one that performs drive control by exchanging signals and control signals from the IC.
Moreover, you may provide the drive circuit 32 as a dedicated circuit (EDU; Electrical actuator Drive Unit). In this configuration, for example, the EDU and the brushless motor device 1 are connected by a wire harness, and an ECU and an EDU on which the control unit 31 is mounted exchange signals via a CAN (Controller Area Network).
Furthermore, the drive circuit 32 may be built in the brushless motor device 1 and the ECU in which the control unit 31 is mounted and the drive circuit 32 may be connected by CAN. In this case, the control unit 31 of the ECU controls the driving of the brushless motor device 1 by inputting the output signal of the Hall IC from the brushless motor device 1 via the CAN.
In addition, the motor control device 3 itself may be built in the brushless motor device 1.

FIG. 4 is a diagram showing output patterns of the position detection Hall IC and the origin learning Hall IC. The number of poles of the magnet 15 shown in FIG. 2 is “8”, the number of slots of the stator 13 is “9”, and the rotor 11 shows the case where the number of poles is “8”.
As shown in FIG. 4, when the rotor 11 is rotated forward, V → U, W → U, W → V, U → V, U, and U windings of the stator 13 for the U-phase, V-phase, and W-phase windings. Repeated energization in order of → W, V → W. In this case, the position detection Hall ICs 17a-1 to 17a-3 are arranged to output HLH, HLL, HHL, LHL, LHH, LLH as output patterns corresponding to the U phase, V phase, and W phase while the rotor 11 makes one rotation. Are sequentially output.
On the other hand, when the rotor 11 is rotated in the reverse direction, W → V, W → U, V → U, V → W, U → W, U for the U-phase, V-phase, and W-phase windings of the stator 13. → Repeat the energization in the order of V. Also in this case, the position detection Hall ICs 17a-1 to 17a-3 have the LLH, LHH, LHL, LHL, HHL, and the like output patterns corresponding to the U phase, V phase, and W phase while the rotor 11 rotates once. HLL is repeatedly output sequentially.

As shown in FIG. 4, the output patterns of the position detection Hall ICs 17a-1 to 17a-3 are repeatedly output while the rotor 11 rotates once. Therefore, the arbitrary position in the axial direction of the motor shaft 10 cannot be accurately detected only by the output patterns of the position detection Hall ICs 17a-1 to 17a-3.
Therefore, in the brushless motor device 1 according to the present invention, the origin learning magnetic pole portion 15b in which one of the position detecting magnetic pole portions 15a extends in the outer peripheral direction of the magnet 15 is provided, and the motor shaft 10 is in the vicinity of the end face of the rod 20. The magnetic flux of the origin learning magnetic pole portion 15b is detected by the origin learning hall IC 17b at a position from the contact point to the contact point.

For example, at a position until the motor shaft 10 contacts from the vicinity of the end face of the rod 20, the origin learning Hall IC 17b is on the origin learning magnetic pole portion 15b, and detects the magnetic flux and outputs an H level signal. .
Since the position detection Hall ICs 17a-1 to 17a-3 are arranged at predetermined angles on the magnet 15, when the rotor 11 is rotated at predetermined rotation angles, the origin learning Hall IC 17b becomes the origin. At the timing of positioning on the learning magnetic pole portion 15b, the output patterns of the position detection Hall ICs 17a-1 to 17a-3 are sequentially switched by the output patterns (1) to (5) shown in FIG. When the output does not change in any one of the combination patterns (5) to (5), it can be specified that the motor shaft 10 is in contact with the rod 20.
At a position where the motor shaft 10 is not in the vicinity of the end face of the rod 20, the output of the origin learning Hall IC 17b is L level, and the output patterns of the position detection Hall ICs 17a-1 to 17a-3 and the origin learning Hall IC 17b The combination pattern with the output pattern is a pattern other than (1) to (5) shown in FIG.

Further, in the origin learning process, when the motor shaft 10 contacts the rod 20 so that the rod 20 does not move, when the motor shaft 10 contacts the rod 20, the axial movement of the motor shaft 10 stops and the rotation of the rotor 11 stops. Drive in ratio.
Accordingly, the outputs of the origin learning Hall IC 17b and the position detection Hall ICs 17a-1 to 17a-3 are any one of (1) to (5) shown in FIG. 4, and the position detection Hall ICs 17a-1 to 17a are shown in FIG. If the output pattern of −3 does not switch sequentially, it can be determined that the motor shaft 10 has come into contact with the rod 20 and stopped moving, and this position is learned as the origin position of the motor shaft 10.

FIG. 5 is a diagram showing a structure of an EGR valve using the brushless motor device according to the first embodiment. The brushless motor device 1 according to Embodiment 1 is used as an actuator of an EGR valve device as shown in FIG. 5, for example. Here, the driven member shown in FIG. 1 corresponds to the valve mechanism 2. The valve mechanism 2 is provided with a valve shaft 20 corresponding to the rod shown in FIG. 1 and arranged so as to be coaxial with the motor shaft 10 of the brushless motor device 1. Note that the brushless motor apparatus 1 includes a housing of the valve mechanism 2 such that the distance A between the end surface of the motor shaft 10 and the end surface of the valve shaft 20 is shorter than the moving distance of the motor shaft 10 during one rotation of the rotor 11. 21 is assembled.

A valve body 22a is fixed to the valve shaft 20, and the return spring 23 biases the valve body 22a in a direction (closed direction) in which the valve body 22a is seated on the valve seat 22b. Further, the valve shaft 20 is movable in the axial direction when the motor shaft 10 contacts one end.
However, in the origin learning process, even if the motor shaft 10 contacts the valve shaft 20, the reaction force from the return spring 23 stops the axial movement of the motor shaft 10 and the rotation of the rotor 11 is stopped. Let

Next, the operation will be described.
FIG. 6 is a flowchart showing origin learning processing by the brushless motor device according to the first embodiment, and shows a case where origin learning is started when the engine key is turned on (power on) in the EGR valve device of FIG.
When power supply to the brushless motor apparatus 1 is started (power is turned on) (step ST1), the control unit 31 proceeds to a process of learning the origin position of the motor shaft 10 in the axial direction.
First, the control unit 31 outputs a control signal for pushing out the motor shaft 10 for each predetermined movement amount to the drive circuit 32. The drive circuit 32 pushes out the motor shaft 10 for each predetermined movement amount according to the control signal of the control unit 31 (step ST2).
Each time the controller 31 pushes the motor shaft 10 by a predetermined amount of movement, the output pattern (a) of the origin learning Hall IC 17b input via the I / F 30 and the position detection Hall ICs 17a-1 to 17a-3 The output pattern (b) is collated (step ST3).

Here, the output patterns (a) and (b) are any one of the combination patterns (1) to (5) shown in FIG. 4, and the position detection is performed even if drive control for pushing the motor shaft 10 is performed. When the output patterns of the hall ICs 17a-1 to 17a-3 do not change (the output patterns do not switch sequentially) (step ST4-1), the control unit 31 causes the motor shaft 10 to abut against the valve shaft 20 to move the motor shaft. It is determined that it is in a stopped state (a state in which the rotation of the rotor 11 is stopped), and the current position of the motor shaft 10 is learned as the origin position (step ST5).
Thus, according to the present invention, it is not necessary to pull the motor shaft 10 to the stopper 11a and then push it to the valve shaft 20 as in the prior art, and the stroke amount of the motor shaft 10 at the time of learning the origin can be greatly reduced. For this reason, the learning time of the drive origin can be remarkably shortened.

The output patterns (a) and (b) are other than the combination patterns (1) to (5) shown in FIG. 4, and even if the drive control for pushing the motor shaft 10 is performed, the position detection Hall IC 17a-1 to When the output pattern of 17a-3 does not change (step ST4-2), the control unit 31 determines that the position of the upper end surface of the valve shaft 20 is in the valve opening direction due to deposits accumulated in the valve seat 22b or wear of the valve shaft 20. It is determined that there is a possibility that the motor shaft 10 is displaced in the pushing direction.
That is, since the distance A + α is from the end surface of the motor shaft 10 to the end surface of the valve shaft 20, at the timing when the origin learning Hall IC 17b is on the origin learning magnetic pole portion 15b (the output of the origin learning Hall IC 17b is H level). The motor shaft 10 does not contact the valve shaft 20 and is further pushed out, and the motor shaft 10 contacts the valve shaft 20 at a timing when the origin learning Hall IC 17b is not on the origin learning magnetic pole portion 15b. It is thought that it is in a state.

As a result of the collation, the control unit 31 starts from the position where the motor shaft 10 contacts the valve shaft 20, that is, the position where the output patterns of the position detection Hall ICs 17a-1 to 17a-3 no longer change. The shaft 10 is pulled in every predetermined amount of movement, and counts each time the output patterns of the position detection Hall ICs 17a-1 to 17a-3 are switched until the output of the origin learning Hall IC 17b becomes H level (Step ST6). Then, it is determined whether or not the count value is less than the specified value (step ST7).
Here, the position where the motor shaft 10 abuts on the valve shaft 20 is set to a count value 0, and the output patterns of the position detection Hall ICs 17a-1 to 17a-3 are shown in FIG. The count value is incremented each time the LLH → LHH → LHL →.
The specified value is that the valve shaft 20 may be displaced in the valve opening direction due to deposits accumulated in the valve seat 22b when the distance A from the lower end surface of the motor shaft 10 to the upper end surface of the valve shaft 20 is set as the distance A. It is a value indicating the capacity (allowable amount at which the distance between the motor shaft 10 and the valve shaft 20 may be separated).
For example, since the movement amount of the motor shaft 10 with respect to the rotation angle of the rotor 11 when the output patterns of the position detection Hall ICs 17a-1 to 17a-3 are switched is known, the allowable amount is set to the position detection Hall ICs 17a-1 to 17a-1. The specified value is represented by the output pattern switching count of 17a-3.

If the count value is less than the specified value (step ST7; YES), the control unit 31 determines that the positional deviation in the valve opening direction of the valve shaft 20 is an allowable amount, pushes out the motor shaft 10 again, and the valve shaft 20 Is learned as the origin position (step ST5).
Further, when the count value is equal to or greater than the specified value (step ST7; NO), the control unit 31 indicates that the position deviation in the valve opening direction of the valve shaft 20 exceeds the allowable amount, and deposits accumulated on the valve seat 22b It is determined that the valve body 22a is stuck (valve valve is stuck) (step ST8).

On the other hand, the output patterns (a) and (b) are other than the combination patterns (1) to (5) shown in FIG. 4, and the output patterns of the position detection Hall ICs 17a-1 to 17a-3 change. When (the output pattern is sequentially switched) (step ST4-3), the control unit 31 determines that the motor shaft 10 has not reached the vicinity of the valve shaft 20, returns to step ST2, and moves the motor with a predetermined movement amount. The shaft 10 is pushed out.
Even when the internal thread of the rotor 11 is worn and the motor shaft 10 does not move even if the rotor 11 rotates, the same collation result as above can be obtained. Therefore, even if the process from step ST2 is performed a predetermined number of times, it is determined to be abnormal if the collation result is obtained.

As described above, according to the first embodiment, the position detection Hall ICs 17a-1 to 17a-3 for detecting the rotation position of the rotor 11 and the predetermined rotation position during one rotation of the rotor 11 are detected. The brushless motor device 1 is assembled to the driven member 2 so as to come into contact with the rod 20 at the movement position of the motor shaft 10 at a predetermined rotational position while the rotor 11 makes one rotation with the origin learning Hall IC 17b. From the output patterns of the position detection Hall ICs 17a-1 to 17a-3 and the output pattern of the origin learning Hall IC 17b, which are switched with the rotation of the rotor 11 when the motor shaft 10 is moved by a predetermined amount. The position where the motor shaft 10 abuts on the rod 20 and the rotation of the rotor 11 is restricted is determined, and this position is the origin. And a control unit 31 for learning as location. With this configuration, there is no need to pull the motor shaft 10 to the stopper 11a and then push it to the valve shaft 20 as in the prior art, and the stroke amount of the motor shaft 10 during origin learning can be greatly reduced. Thereby, the learning time of the drive origin can be significantly shortened. In addition, since it is not necessary to restrict the movement of the motor shaft 10 mechanically by the stopper 11a, the origin learning temporary start position is not shifted due to wear of the stopper 11a, and the origin learning process is stably performed. Can do.

Further, according to the first embodiment, the magnet 15 provided on the surface orthogonal to the rotation axis of the rotor 11 and having different magnetic poles alternately arranged around the rotation axis of the rotor 11 and the position detection magnetic pole portion 15a. A disc-shaped magnet 15 having an origin learning magnetic pole portion 15b formed by extending one of the adjacent magnetic pole pairs in the outer edge direction, and the position detection Hall IC 17a faces the position detection magnetic pole portion 15a. The position detection magnetic pole portion 15a of the magnet 15 rotating together with the rotor 11 is detected, and a signal indicating the rotation position of the rotor corresponding to the magnetic pole is output. Learning the origin of the magnet 15 which is arranged on the same plane as the detection Hall IC 17a with a pitch diameter different from that of the position detection Hall IC 17a and rotates together with the rotor 11. By detecting only the magnetic flux of the magnetic pole portion 15b, a rotor 11 corresponding to the magnetic pole output a signal indicating a predetermined rotational position between one rotation. Since the position detection Hall IC 17a and the origin learning Hall IC 17b are installed on the same plane as described above, they can be mounted on the same printed circuit board 16 and can be easily manufactured.

Furthermore, according to the first embodiment, the distance between the motor shaft 10 and the rod 11 is shorter than the moving distance of the motor shaft 10 during one rotation of the rotor 11, and the origin learning Hall IC 17b is used for origin learning. The motor shaft 10 moves from the vicinity of the rod 20 to a position until it abuts at a timing when the motor shaft 10 comes to a position facing the magnetic pole portion 15b. With this configuration, the amount of movement stroke of the motor shaft 10 necessary for origin learning can be reduced, and the time required for origin learning can be shortened.

In the present invention, any component of the embodiment can be modified or any component of the embodiment can be omitted within the scope of the invention.

The brushless motor device according to the present invention is suitable for an actuator such as an EGR valve device of a vehicle because the time required for learning the origin position for driving the motor shaft can be shortened.

1 brushless motor device, 2 driven member (valve mechanism), 3 motor control device, 10 motor shaft, 11 rotor, 12 case, 13 stator, 14 bearing, 15 magnet, 15a position detection magnetic pole, 15b origin learning magnetic pole Part, 16 printed circuit board, 17a, 17a-1 to 17a-3 position detection Hall IC, 17b origin learning Hall IC, 20 rod (valve shaft), 21 housing, 22a valve body, 22b valve seat, 23 return spring, 30 interface (I / F), 31 control unit, 32 drive circuit.

Claims

In the brushless motor device for driving the rod of the driven member arranged coaxially with the motor shaft, the motor shaft moves in the axial direction as the rotor rotates.
A position detecting sensor for detecting the rotational position of the rotor;
An origin learning sensor unit for detecting a predetermined rotational position during one rotation of the rotor;
The motor shaft is mounted on the condition that the brushless motor device is assembled to the driven member so as to come into contact with the rod at a moving position of the motor shaft at a predetermined rotational position during one rotation of the rotor. From the output pattern of the position detection sensor unit and the output pattern of the origin learning sensor unit, which is switched with the rotation of the rotor when moved by a predetermined amount, the motor shaft comes into contact with the rod and the rotor A brushless motor device comprising: a control unit that determines a position where rotation of the motor is restricted and learns the position as an origin position.
A position detection magnetic pole portion provided on a surface orthogonal to the rotation axis of the rotor and formed by alternately arranging different magnetic poles around the rotation axis of the rotor, and one of the adjacent magnetic pole pairs of the position detection magnetic pole portion A disk-shaped magnet having an origin learning magnetic pole portion formed by extending one in the outer edge direction,
The sensor unit for position detection is
Detecting the magnetic flux of the position detection magnetic pole portion of the magnet, which is disposed opposite to the position detection magnetic pole portion and rotates together with the rotor, and outputs a signal indicating the rotation position of the rotor corresponding to the magnetic pole. ,
The origin learning sensor unit is
The position detection sensor unit is disposed on the same plane as the position detection sensor unit with a different pitch diameter, and detects only the magnetic flux of the origin learning magnetic pole unit of the magnet that rotates together with the rotor. 2. The brushless motor device according to claim 1, wherein a signal indicating a predetermined rotational position is output while the rotor corresponding to 1 rotates once.
Timing at which the distance between the motor shaft and the rod is shorter than the moving distance of the motor shaft during one rotation of the rotor, and the origin learning sensor unit comes to a position facing the origin learning magnetic pole unit The brushless motor device according to claim 2, wherein the motor shaft moves to a position from the vicinity of the rod to contact.
In the motor control device which controls the drive of the brushless motor device according to claim 1,
The motor shaft is mounted on the condition that the brushless motor device is assembled to the driven member so as to come into contact with the rod at a moving position of the motor shaft at a predetermined rotational position during one rotation of the rotor. From the output pattern of the position detection sensor unit and the output pattern of the origin learning sensor unit, which is switched with the rotation of the rotor when moved by a predetermined amount, the motor shaft comes into contact with the rod and the rotor A motor control device comprising: a control unit that discriminates a position where rotation of the motor is restricted and learns the position as an origin position.
In the origin learning method of the brushless motor device according to claim 1,
The motor shaft is mounted on the condition that the brushless motor device is assembled to the driven member so as to come into contact with the rod at a moving position of the motor shaft at a predetermined rotational position during one rotation of the rotor. From the output pattern of the position detection sensor unit and the output pattern of the origin learning sensor unit, which is switched with the rotation of the rotor when moved by a predetermined amount, the motor shaft comes into contact with the rod and the rotor An origin learning method characterized by discriminating a position where rotation of the lens is restricted and learning this position as an origin position.