JP2005132138A - Vehicular motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular brushless motor which can control the motor without any malfunction when detecting abnormal temperature in the motor or abnormal voltage of the power supply, and saving a space inside a vehicle. <P>SOLUTION: The vehicular motor 30 mounted on a vehicle comprises an abnormal voltage detection means 68, an abnormal current detection means 69, an abnormal temperature detection means 70, and a control means 62 to limit the current supplied to an excitation coil 41 or to control the current to be turned OFF when the abnormal voltage detection means 68, the abnormal current detection means 69 or the abnormal temperature detection means 70 detects each abnormal value. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle motor installed in a vehicle.

A brushless motor which is a conventional motor mounted for air conditioning of a vehicle will be described (see Patent Document 1).
In a conventional brushless motor for a vehicle, a magnetic pole position detecting element for detecting the magnetic pole of the rotor and a control circuit for supplying current to the exciting coil based on the magnetic pole position of the rotor detected by the magnetic pole position detecting element are not provided. In general, it is provided on a substrate installed inside the motor.

Some brushless motors for vehicles are provided with a temperature sensor for detecting a temperature rise inside the motor on the inner wall of the housing (see Patent Document 2).
According to such a brushless motor, when it is detected that the temperature sensor has risen to a predetermined temperature, a detection signal is output from the temperature sensor.
The detection signal is input to a controller provided outside the motor. The controller is formed so as to be able to control the number of rotations of the motor, and controls the number of rotations based on the detection signal input from the temperature sensor to prevent temperature rise.

In addition to the vehicle brushless motor described above, a detection circuit that detects whether the power supply voltage supplied to the exciting coil is an overvoltage or a low voltage is provided, and an abnormal voltage of the power supply is detected. Conventionally, it is also possible to adjust the rotational speed of a motor.
Also in such a brushless motor for a vehicle, control when an abnormal voltage of the power source is detected is performed from the outside of the motor.

Japanese Unexamined Patent Publication No. 2000-4466 (0070, FIG. 1 etc.) JP-A-8-47283 (0013, FIG. 3 etc.)

In the motor, if abnormal temperature inside the motor, abnormal voltage of the power supply, etc. are detected, the control circuit may be damaged if left as it is, so the current supplied to the exciting coil is limited or turned off. It is preferable to deal with this. In such a case, conventionally, an abnormal temperature or abnormal voltage detection signal is output to the outside of the motor, and an abnormal temperature or abnormal voltage is dealt with by a control signal output to the motor by an external control circuit or the like based on this detection signal. .
On the other hand, the inside of the vehicle, especially in the hood, is an environment where there is a lot of electrical noise because the engine is driven and other devices are operating. When a vehicle motor is installed in such an environment and a detection signal is output to the outside of the motor or a control operation is performed by a control signal from the outside of the motor, the detection signal or control signal is directly exposed to noise. There was a problem that there was a risk of malfunction.

  In addition, by providing a control circuit for abnormal temperatures and abnormal voltages outside the motor, a space for mounting the control circuit is also required, so that there is a problem that space saving inside the vehicle cannot be achieved.

  Therefore, an object of the present invention is for a vehicle that can execute control of a motor without malfunction when an abnormal temperature inside the motor, an abnormal voltage of a power source, or the like is detected, and can save space inside the vehicle. It is to provide a motor.

According to the vehicle motor according to the present invention, in the vehicle motor mounted on the vehicle having the excitation coil, the abnormal voltage detection for detecting that the power supply voltage for supplying the current to the excitation coil is an abnormal value. Means, an abnormal current detecting means for detecting that the current value supplied to the exciting coil is an abnormal value, an abnormal temperature detecting means for detecting that the temperature inside the motor is an abnormal value, and the abnormal voltage detecting means When the abnormal current detecting unit or the abnormal temperature detecting unit detects each abnormal value, the abnormal current detecting unit or the abnormal temperature detecting unit includes a control unit that controls to limit or turn off a current supplied to the exciting coil. It is said.
According to this configuration, the detection signal such as abnormal temperature or abnormal voltage is not output to the outside of the motor, and the abnormal temperature or abnormal voltage is not dealt with by the control signal from the outside of the motor. It is possible to provide a vehicle motor that is less susceptible to malfunction and has few malfunctions. Further, since there is no need for a control circuit installation space corresponding to abnormal temperature and abnormal voltage outside the motor, space saving inside the vehicle can be achieved.
The control means here refers to a wide range of devices including a storage means for storing a program as long as it operates by a program.

According to the vehicle motor of the present invention, the rotor having a plurality of magnets fixed to the rotating shaft so as to rotate together with the rotating shaft, the stator core, and the plurality of exciting coils wound around the stator core, And a control means for rotationally driving the rotor by controlling the energization timing of the current supplied to each excitation coil, and supplying the current to the excitation coil in the vehicle brushless motor mounted on the vehicle The abnormal voltage detection means for detecting that the power supply voltage for the power supply is abnormal value, the abnormal current detection means for detecting that the current value supplied to the exciting coil is abnormal value, and the temperature inside the motor is abnormal value An abnormal temperature detecting means for detecting the presence, the abnormal voltage detecting means, the abnormal current detecting means or the abnormal temperature detecting means detects the abnormal values. If the is characterized by comprising storage means programmed protected program is stored such that the control means or off to limit the current supplied to the exciting coils.
By adopting this configuration, detection signals such as abnormal temperatures and abnormal voltages are not output to the outside of the motor, and abnormal temperatures and abnormal voltages are not dealt with by control signals from the outside of the motor. Therefore, it is possible to provide a vehicular brushless motor with less malfunction. Further, since there is no need for a control circuit installation space corresponding to abnormal temperature and abnormal voltage outside the motor, space saving inside the vehicle can be achieved.
The control means according to claim 2 has a different concept from the control means according to claim 1 in that it operates based on the protection program stored in the storage means.

Further, the storage means is a semiconductor storage device, and the control means is a central processing unit capable of reading and executing the control program, and the central processing unit and the semiconductor storage device are on the same printed circuit board. The printed circuit board may be housed and provided so as not to be exposed to the outside.
According to this configuration, the normal drive control of the motor and the control for dealing with abnormal temperature and abnormal voltage can be executed with one printed circuit board, and since it is not exposed to the outside, it is not easily affected by noise. The frequency of malfunctions can be reduced.

Further, a housing to which the stator is fixed is provided on one side surface, a case formed to be attachable to another device is provided on the other side surface of the housing, and the printed circuit board is connected to the housing. It may be characterized by being housed between the case.
According to this, it can be set as the structure which a printed circuit board does not expose outside the motor.

  According to the vehicle motor of the present invention, it is possible to reduce the occurrence frequency of malfunction due to noise and to realize space saving.

  The vehicle motor described below is specifically a brushless motor, and a program for dealing with detection of overvoltage, undervoltage or overcurrent of the power source, or overheating inside the motor is stored in a ROM or the like. The information is stored in the storage means and the storage means is built in.

Hereinafter, an example of a vehicle motor will be described with reference to the drawings.
The motor for vehicles in a present Example is a brushless motor of an outer rotor type | mold, and is a motor for ventilation used for the air conditioner for vehicles. Therefore, FIG. 1 illustrates a structure in which the impeller 33 is attached to the tip of the rotating shaft 32.

First, the overall configuration of a brushless motor 30 for vehicles (hereinafter simply referred to as a motor) will be described.
The motor 30 includes a rotating shaft 32, a rotor 34 attached to the rotating shaft 32 and rotating together with the rotating shaft, and a stator 36 that rotationally drives the rotor 34.
The rotary shaft 32 passes through the center portion of the stator 36 and the housing 42 and is rotatably held by bearings 45 and 58. A position detecting magnet 48 is fixed to the lower end of the rotating shaft 32.

The rotor 34 includes a yoke 37 made of a magnetic material and formed into a bottomed bowl shape, and a plurality of magnets 38 arranged at predetermined positions on the inner wall surface of the yoke.
A fixed portion 39 for fixing the rotating shaft 32 is formed at the center of the yoke 37. The rotary shaft 32 is press-fitted and fixed to the fixed portion 39.

The stator 36 is provided in the rotor 34 and generates a rotating magnetic field for driving the rotor 34 to rotate.
The stator 36 has a stator core 40 formed by laminating electromagnetic steel plates, and an excitation coil 41 wound around the stator core 40. The upper and lower surfaces of the stator core 40 are held by a holding member 44 made of a nonmagnetic material, and an exciting coil 41 is wound around the holding member 44.
The stator 36 is formed with a fitting hole 54 for fitting with the housing 42 at the center. The housing 42 is provided with a fitting protrusion 56 that protrudes upward. The stator 36 is fixed to the housing 42 by press-fitting a fitting protrusion 56 of the housing 42 into the fitting hole 54.

The housing 42 is sized to cover the opening side of the yoke 37, holds the rotating shaft 32 by a bearing 45 that rotatably holds the rotating shaft 32, and fixes the stator 36.
Below the housing 42, a control board 46, which is a printed board on which a control circuit 59 for controlling the rotation of the motor is formed, is fixed by screws or the like (not shown).
A specific configuration of the control circuit 59 will be described later.

A lower portion of the housing 42 is covered with a case 50.
The case 50 is formed with an attachment portion 52 for fixing with a bolt or the like inside the vehicle. A housing recess 51 capable of housing and holding the housing 42 is formed on the upper surface of the case 50.
Therefore, the control board 46 is sandwiched between the housing 42 and the case 50 so as not to be exposed to the outside.

Next, the circuit configuration of the motor will be described with reference to FIG.
The control circuit 59 has a plurality of magnetic sensors 60 (such as Hall elements and magnetic resistances) for detecting the position of the rotating shaft 32 by the magnet 48, and a predetermined timing based on the detected position of the rotating shaft 32. A central processing unit (hereinafter simply referred to as a CPU) 62 for instructing to supply a current having a magnitude to the exciting coil 41, and a switch circuit 63 for supplying a motor driving current to the exciting coil 41 based on an instruction from the CPU 62. I have. The switch circuit 63 is configured by bridge-connecting power type transistors 65 such as FETs.

The CPU 62 is connected to a ROM 64 that is storage means. The ROM 64 stores a control program A for executing operations as described later. The CPU 62 reads the control program A, and controls the switch circuit 63 to execute a motor drive operation based on the read control program A.
In the present embodiment, as the control program stored in the ROM 64, a control program A is a program in which a protection program for dealing with an abnormality is integrated in addition to a normal control program. However, the programs stored in the ROM 64 are separate programs, a control program for executing normal control and a protection program for executing control for responding to an abnormality. Also good.

A power supply 67 is connected to the control circuit 59. The power source 67 of this embodiment is a 12V or 24V battery mounted inside the vehicle.
The control circuit 59 is provided with an abnormal voltage detection circuit 68 as means for detecting when the power supply voltage input from the power supply 67 becomes an abnormal voltage (overvoltage or low voltage). As shown in FIG. 4, the abnormal voltage detection circuit 68 includes a comparator 71 that compares an input power supply voltage value with a preset reference voltage value. The detection signal c output from the comparator 71 is input to the CPU 62.
Note that such an abnormal voltage detection circuit 68 is actually composed of two circuits for overvoltage detection and low voltage detection, and the power supply voltage is overvoltage and low voltage. Each is detected.

  Further, the control circuit 59 is provided with an abnormal current detection circuit 69 as means for detecting when the value of the current flowing through the exciting coil 41 becomes an abnormal current (overcurrent). The abnormal current detection circuit 69 includes a resistor that converts a current flowing through the exciting coil into a voltage, and a comparator that compares this voltage with a preset reference voltage value (not shown). The detection signal d output from the comparator is input to the CPU 62.

  Further, the control circuit 59 is provided with an overheat detection circuit 70 as means for detecting when the temperature inside the motor becomes an abnormal temperature (specifically, when the motor is overheated). In the overheat detection circuit 70, a thermistor (not shown) mounted on the control board 60 on which the control circuit 59 is formed detects a temperature change as a resistance value change. A detection signal f output from the overheat detection circuit 70 is input to the CPU 62.

Next, the operation of the CPU will be described.
First, the operation during normal motor rotation in the CPU 62 will be described.
The CPU 62 controls the rotation speed by PWM (Pulse Width Modulation) control. The PWM control itself is a known control method.

The CPU 62 receives a speed command voltage a that instructs the rotational speed of the motor from outside the motor such as the main body of the air conditioner in the vehicle. The PWM generation means 72 in the CPU 62 generates a pulse voltage having a predetermined width based on the input speed command voltage a.
On the other hand, the current motor rotation speed signal e is output from the CPU 62 to the outside of the motor.

A magnetic position signal b is input into the CPU 62 from the magnetic sensor 60. The phase switching means 74 in the CPU 62 calculates the actual rotational speed from the input magnetic position signal b, obtains the difference from the indicated speed indicated by the speed command voltage a from this value, and based on this, the switch circuit The ratio of the on-off time of the power transistor 65 in 63 is obtained.
The on / off time ratio calculated by the phase switching means 74 is input to the gate drive circuit 66 in the CPU 62. The gate drive circuit 66 performs on / off control of the power transistor 65 in the switch circuit 63 in accordance with the calculated ratio of on / off time. As a result, the motor 30 is controlled to perform a constant rotation at a speed instructed from the outside.

  Note that the PWM generation means 72 and the phase switching means 74 as described above are realized by the CPU 62 reading the control program A stored in advance in the ROM 64 and executing it.

Next, the operation when an abnormality is detected in which the power supply voltage is in an overvoltage state, the power supply voltage is in a low voltage state, the current supplied to the exciting coil is in an overcurrent state, or the motor is in an overheated state will be described.
When the protection means 76 of the CPU 62 determines that the power supply 67 is overvoltage or undervoltage based on the detection signal c from the abnormal voltage detection circuit 68, the output of the switch circuit 63 is output via the gate drive circuit 66. Turn off.

  When the detection means d from the abnormal current detection circuit 69 determines that the current supplied to the exciting coil 41 is an overcurrent, the protection means 76 of the CPU 62 switches via the gate drive circuit 66. The output of the circuit 63 is turned off.

  The protection means 76 of the CPU 62 turns off the output of the switch circuit 63 via the gate drive circuit 66 when it is determined by the detection signal f from the overheat detection circuit 70 that the temperature in the motor is overheated. .

In addition to the motor protection control that is executed when each abnormal state described above is detected, the CPU 62 detects the motor restraint, and if it detects that the motor is restrained, the CPU 62 It has a function to deal with in order to prevent damage and the like.
This function will be described.
The CPU 62 receives the rotor magnetic pole position signal b detected from the magnetic sensor 60. If the constraint detection means 77 of the CPU 62 detects that the magnetic pole position signal b has not changed for a predetermined time even though the drive current is supplied to the excitation coil 41, the rotor 34 or the rotating shaft 32 is It is determined that it is in a state where it cannot be rotated due to the restraint.
In such a case, the constraint detection unit 77 of the CPU 62 turns off the current output from the switch circuit 63 via the gate drive circuit 66.

  When the power supply voltage is overvoltage, the power supply voltage is low, the supply current to the exciting coil is overcurrent, and the motor is overheated, the output of the switch circuit 63 is detected as described above. The protection means 76 for stopping the motor by turning OFF and the restriction detection means 77 for detecting the restriction are realized by the CPU 62 reading the control program A stored in advance in the ROM 64 and executing it by the CPU 62.

  In the embodiment described above, the CPU 62 turns off the current supplied from the switch circuit 63 to the exciting coil 41 when detecting each abnormal state (including motor restraint), or damages to the control circuit or the motor itself. I tried to prevent damage. However, when each abnormal state is detected, it is not limited to turning off the current, and control may be performed so as to simply reduce the rotational speed.

Further, since the motor of the present embodiment has three phases, the power type transistor 65 in the switch circuit 63 is used in two for each phase, for a total of six, and three magnetic sensors 60 are also used. However, the vehicle motor of the present invention is not limited to three phases.
Furthermore, in the said Example, although the brushless motor was demonstrated as an example of the motor for vehicles, it is not limited to a brushless motor.

  While the present invention has been described in detail with reference to a preferred embodiment, the present invention is not limited to this embodiment, and it goes without saying that many modifications can be made without departing from the spirit of the invention. .

It is sectional drawing which shows the whole structure of the motor for vehicles concerning this invention. It is a top view of the motor for vehicles. It is a block diagram which shows the control circuit of the motor for vehicles. It is a circuit diagram of an abnormal voltage detection circuit.

Explanation of symbols

30 Vehicle motor 32 Rotating shaft 33 Impeller 34 Rotor 36 Stator 37 Yoke 38 Magnet 39 Fixed portion 40 Stator core 41 Exciting coil 42 Housing 44 Holding member 45 Bearing 46 Control board 48 Magnet 50 Case 51 Storage recess 52 Mounting portion 54 Fitting hole 56 fitting protrusion 59 control circuit 60 magnetic sensor 62 central processing unit (CPU)
63 Switch circuit 65 Power type transistor 66 Gate drive circuit 67 Power supply 68 Abnormal voltage detection circuit 69 Abnormal current detection circuit 70 Overheat detection circuit 71 Comparator 72 Generation means 74 Phase switching means 76 Protection means 77 Constraint detection means A Control program a Speed command voltage b Magnetic position signal c, d, f Detection signal e Speed signal

Claims (4)

In a vehicle motor that has an excitation coil and is mounted on a vehicle,
An abnormal voltage detecting means for detecting that the power supply voltage for supplying current to the exciting coil is an abnormal value;
An abnormal current detecting means for detecting that the current value supplied to the exciting coil is an abnormal value;
An abnormal temperature detecting means for detecting that the temperature inside the motor is an abnormal value;
Control means for controlling the current supplied to the exciting coil to be limited or turned off when the abnormal voltage detecting means, the abnormal current detecting means or the abnormal temperature detecting means detects each abnormal value. A vehicle motor comprising the vehicle motor. A rotor fixed to the rotating shaft so as to rotate together with the rotating shaft, and having a plurality of magnets;
A stator having a stator core and a plurality of exciting coils wound around the stator core;
A vehicle motor mounted on a vehicle, comprising a control means for controlling the energization timing of the current supplied to each excitation coil to rotate the rotor.
An abnormal voltage detecting means for detecting that the power supply voltage for supplying current to the exciting coil is an abnormal value;
An abnormal current detecting means for detecting that the current value supplied to the exciting coil is an abnormal value;
An abnormal temperature detecting means for detecting that the temperature inside the motor is an abnormal value;
When the abnormal voltage detecting means, the abnormal current detecting means or the abnormal temperature detecting means detects the abnormal values, the control means limits or turns off the current supplied to the exciting coils. A vehicle motor comprising storage means for storing a programmed protection program. The storage means is a semiconductor storage device,
The control means is a central processing unit that can read and execute the protection program,
The central processing unit and the semiconductor memory device are mounted on the same printed circuit board,
3. The vehicle motor according to claim 2, wherein the printed circuit board is housed and provided so as not to be exposed to the outside. A housing to which the stator is fixed is provided on one surface;
On the other surface of the housing, a case is provided that can be attached to other equipment.
4. The vehicle motor according to claim 3, wherein the printed circuit board is housed and provided between a housing and a case.

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