JP2000224884A - Detecting device and electric car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact and lightweight detecting device that can detect a fault, and an electric car that uses the detecting device. SOLUTION: Three hole elements 64U, 64V, and 64W are provided integrally so that an electrical angle is set to 60 degrees, and the size and weight of a detecting device 62 is reduced. Then, a center hole element 64V is inverted for arrangement, and an output waveform is inverted, thus preventing the output of the hole elements 64U, 64V, and 64W from becoming identical regardless of the position of a rotor, and hence judging the presence or absence of a fault by detecting whether the output is the same or not.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detection device for magnetically detecting a rotation angle of a motor, and more particularly to a detection device suitable for a wheel motor type electric vehicle using the detection device.

[0002]

2. Description of the Related Art Conventionally, in an electric vehicle, a motor drive device for a vehicle is provided, and the motor is driven by supplying current to the motor from a battery mounted on the vehicle. Among them, a wheel motor type electric vehicle is provided with a motor for each wheel, and travels by transmitting rotation generated by each motor to driving wheels.

[0003]

In this wheel motor type electric vehicle, a motor is housed in a wheel.
Although it has the advantage of high efficiency without transmission loss, it has a problem that the unsprung weight becomes heavy to accommodate the motor, and it is difficult to improve the riding comfort. For this reason, the weight reduction of the motor is the biggest issue for the practical use of the wheel motor type electric vehicle.

A DC brushless motor is generally used as the wheel motor. To drive the DC brushless motor, it is necessary to detect a rotational position and excite a coil. For detecting the rotational position, a detecting device in which three Hall elements for magnetic detection are combined so as to have an electrical angle of 120 degrees is generally used.

The present inventor has devised to arrange a Hall element at an electrical angle of 60 degrees in order to reduce the size and weight of the detection device. However, in the case of the arrangement at 60 degrees, unlike the arrangement of 120 degrees, the position of the motor in which the outputs of all the hall elements are the same occurs, and by detecting that the outputs of the hall elements are the same. A new problem has arisen that the failure judgment cannot be made.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to reduce the size and size of the device.
An object of the present invention is to provide a detection device capable of detecting a failure while reducing the weight and an electric vehicle using the detection device.

[0007]

According to a first aspect of the present invention, there is provided a detection device for magnetically detecting a rotation angle of a motor, wherein the detection device is disposed at a predetermined electric angle and is binary. Three or more magnetic detection sensors for detecting the strength of a magnetic field, a reversing device for reversing the output of at least one of the magnetic detection sensors, and a sensor when all the magnetic detection sensors have the same output. And an output device for outputting an abnormality.

According to a second aspect of the present invention, a detection device for magnetically detecting a rotation angle of a motor and a method of rotating the motor so that an electrical angle with respect to a magnetic pole to be detected is 60 degrees, Three magnetic detection sensors for detecting the intensity of the magnetic field in a binary manner, a reversing device for reversing the output of the magnetic detection sensor at the center position among the three magnetic detection sensors, and three magnetic detection sensors And an output device for outputting a sensor abnormality when the outputs are equal.

According to a third aspect of the present invention, in the second aspect, the reversing device outputs three different magnetic detection sensors at the center position to the other two magnetic detection sensors in the same magnetic flux direction. It is a technical feature that the configuration is such that the occurrence of the error occurs.

A fourth aspect of the present invention is characterized in that, in the second aspect, the reversing device is an inverter element provided at an output terminal of the magnetic detection sensor at the three central positions.

According to a fifth aspect of the present invention, in a wheel motor type electric vehicle, the electric angle is set to be 60 degrees with respect to the polarity to be detected, and the intensity of the magnetic field is detected in a binary manner. Magnetic detection sensors, a reversing device for reversing the output of the magnetic detection sensor at the center position of the three magnetic detection sensors, and an alarm when the outputs of the three magnetic detection sensors are the same. And an alarm device that issues an alarm.

According to the first aspect of the present invention, it is possible to prevent the outputs of all the magnetic detection sensors from being equal by inverting the output of one of the magnetic detection sensors. For this reason, by detecting that the outputs of the magnetic detection sensors are equal, it is possible to determine a failure of the detection device, a disconnection of a cable of the detection device, a disconnection of a connector, and the like.

According to the second aspect of the present invention, since the three magnetic detection sensors are juxtaposed so that the electrical angle becomes 60 degrees, the size and weight of the detection device can be reduced. On the other hand, when the electrical angle is set to 60 degrees, the output of the magnetic detection sensor may become the same, but since the output of the magnetic detection sensor at the center position among the three magnetic detection sensors is inverted,
The outputs do not all become equal, and it is possible to detect failure of the detection device, disconnection of the cable of the detection device, disconnection of the connector, and the like.

According to the third aspect of the present invention, the reversing device is configured so that the three magnetic detection sensors at the center position generate different outputs in the same magnetic flux direction with respect to the other two magnetic detection sensors. Therefore, the configuration can be simplified.

According to the fourth aspect of the present invention, since the output terminals of the three magnetic detection sensors at the center are provided with inverter elements, the output of the magnetic detection sensor is maintained even when the detection directions of the magnetic detection sensors are the same. Prevent equality.

According to the fifth aspect of the present invention, since the three magnetic detection sensors are provided so that the electrical angle becomes 60 degrees, the size and weight of the detection device can be reduced. Therefore, the unsprung weight of the wheel motor can be reduced. On the other hand, when the electrical angle is set to 60 degrees, the output of the magnetic detection sensor may become the same, but since the output of the magnetic detection sensor at the center position among the three magnetic detection sensors is inverted, the output is Will not all be equal. Therefore, when the outputs of the three magnetic detection sensors are the same, an alarm can be issued by the alarm device before starting.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a wheel motor provided with a detection device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a wheel motor 10 according to an embodiment of the present invention, and FIG. 2 is a sectional view of a main part of the wheel motor 10 shown in FIG. As shown in the figure,
The drive unit case 11 has a two-part structure including two dish-shaped first and second casings 12 and 13 disposed inside and outside the vehicle. By connecting the first and second casings 12 and 13 with bolts (not shown), a motor chamber 15 having a substantially circular cross section is formed between the first and second casings 12 and 13. You. The motor chamber 15 houses a motor 24. The drive device case 11 is attached to a chassis of the vehicle via a wishbone type suspension device (not shown).

A planetary gear unit 31 as a transmission gear device is disposed radially inward of the motor 24.
The rotation of the motor 24 is reduced by a factor of 7.2 by the planetary gear unit 31 and output to the output shaft 38.
A wheel hub 39 is connected to the output shaft 38. A wheel disk 45 is fixed to an outer periphery of the flange portion 39b of the wheel hub 39 by a bolt b2. The wheel disc 45 has a cup-like shape, and includes a flat bottom 45a and a cylindrical portion 45b integrally formed on the outer periphery of the bottom 45a, and an outer edge of the cylindrical portion 45b. Is fixed to the tire 47.

FIG. 2 shows the structure of this wheel motor.
This will be described in more detail with reference to FIG. Second casing 13
An opening is formed at the center of the wheel hub 39, and the sleeve portion 39a of the wheel hub 39 is inserted into the opening.
Is rotatably supported by the bearing 40 with respect to the second casing 13. Then, the sleeve portion 39a
An output shaft 38 is provided in the inside, and the sleeve portion 39a and the output shaft 38 are spline-engaged. A flange portion 38a is integrally formed at an outer end portion of the output shaft 38, a screw portion 38b is formed at an inner end portion of the output shaft 38, and a nut 42 is screwed to the screw portion 38b. The output shaft 38 and the wheel hub 39 are prevented from moving in the axial direction with respect to each other. In addition, the motor chamber 1 is provided through the opening.
A seal 59 is provided between the opening and the sleeve portion 39a so that the oil inside 5 does not leak out of the drive device case 11.

The stator 25 of the motor 24 in the motor chamber 15 is fixed to the cylindrical portion 12a of the first casing 12 by bolts bll. The stator 25 includes a stator core 25a and a stator coil 26 wound around the stator core 25a. A rotor 27 is rotatably disposed inside the stay core 25a in the radial direction with a predetermined gap (gap) therebetween with respect to the drive device case 11. The rotor 27 includes a rotor shaft 21, a rotor hub 29 fixed to the rotor shaft 21, and a rotor core 30 fixed to an outer peripheral edge of the rotor hub 29.
And permanent magnets 50 are arranged at a plurality of locations in the circumferential direction of the rotor core 30.

The outer end of the rotor shaft 21 is rotatably supported by the bearing 28 with respect to the first casing 12, and the inner end of the rotor shaft 21 is connected to the flange 38a of the output shaft 38. Is rotatably supported by a bearing 33.

As described above, the planetary gear unit 31 as a transmission gear device is provided radially inward of the motor 24.
Is arranged. In this case, since the motor 24 and the planetary gear unit 31 are overlapped in the axial direction, the axial dimension of the vehicle motor drive device can be reduced. The planetary gear unit 31 is rotatably supported by the sun gear S and the ring gear R spline-engaged with the rotor shaft 21, the carrier CR formed by the flange portion 38a, and the sun gear S. S and a gear element of a pinion P meshed (engaged) with the ring gear R,
The rotation generated by the motor 24 is the sun gear S
And the reduced rotation is output to the output shaft 38. The ring gear R is connected to the second casing 13
Gear flange 14 fixed by bolts bl
Fixed to

In order to detect the number of revolutions of the rotor 27, an annular projection 94 is formed at a predetermined position on the rotor 27, and the inner periphery of the annular projection 94 is magnetized corresponding to the permanent magnet 50. A ring magnet 95 is provided. And
A detection device 62 that detects the rotational position of the rotor 27 is provided in the drive device case 11 so as to face the ring magnet 95. The detection device 62 is fixed to the first casing 12 by a bolt (not shown).

FIG. 3 shows the ring magnet 95 and the detecting device 62.
FIG. 3 is a diagram showing the correspondence relationship with the arrow A in FIG. 2.
The ring magnet 95 is formed by forming a resin containing a magnetic material such as soft iron into a cylindrical shape. The ring magnet 95 has twelve magnetized portions 95d in accordance with the polarities of the twelve permanent magnets 50. Here, by applying a strong magnetic field to the soft iron included in the ring magnet 95, the magnetized portion 95 shown in FIG.
d is formed. That is, by providing the 12-pole magnetized portion 95d such that the mechanical angle of 60 degrees shown in the drawing corresponds to the electrical angle of 360 degrees from the N pole to the N pole, the permanent magnet 50 of the motor 24 is provided. Respectively.

FIG. 4 shows the detecting device 62.
4A is a front view of the detection device 62 viewed from the A side in FIG. 2, and FIG. 4B is a side view of the detection device 62 of FIG. FIG. 4 (C) shows FIG.
It is a figure which expands and shows C part in (A). As shown in FIG. 4A, the detection device 62 includes three Hall elements 64.
U, 64V, slot 63a for accommodating 64W,
63b and 63c are formed. The slot 63a,
63b and 63c are, as shown in FIG. 2 and FIG.
The protrusion 62 c is formed to protrude toward the ring magnet 95. That is, as shown in FIG. 3, the lower surface of the protruding portion 62c faces the inner periphery of the ring magnet 95, and the Hall elements 64U, 64V, 64W disposed on the lower surface form the ring portion 9c.
5 is detected.

As shown in FIG. 4C, the Hall element 64
U, 64V and 64W are arranged at intervals of 10 degrees in mechanical angle of the motor 24. That is, as described above with reference to FIG.
Since it is set to 0 degrees, the Hall elements 64U, 64U
V and 64W are arranged at an electrical angle of 60 degrees. In the first embodiment, the center Hall element 64V of the three Hall elements is attached to the other two magnetic detection sensors 64U and 64W in the opposite senses.
The output has been inverted.

FIG. 5 shows a wheel motor 10 according to this embodiment.
And a control device 70. A detection signal from the detection device 62 provided in the wheel motor 10 is transmitted to a signal line 65.
And input to the control device 70 via the connector 66. The control device 70 controls the rotor 2 based on the detection signal.
7, the wheel motor 10 is driven by exciting the stator coil 26 (see FIG. 2) via the power lines 72U, 72V, 72W.

Here, failure detection by the control device 70 of this embodiment will be described. Prior to the failure detection, as described above, in the present embodiment, the center Hall element 64V of the three Hall elements is replaced with the other two magnetic detection sensors 6
The reason why the detection directions are reversed to 4U and 64W and the output is reversed will be described.

FIG. 6 shows the case where the electrical angle is 60 degrees as described above.
The output waveform when the center Hall element is arranged without being inverted is shown. In the figure, a vertical chain line interval corresponds to an electrical angle of 60 degrees. Counting from the rise of the waveform of the Hall element 64U in the figure, the waveforms of all the Hall elements 64U, 64V, 64W are “high” during the electrical angle of 120 ° to 180 °.
It has become. On the other hand, the waveforms are all "low" between the electrical angles of 300 ° to 360 °.

FIG. 7 shows an output waveform of this embodiment. As shown in the figure, the output waveform is inverted by inverting and arranging the central Hall element 64V.
Regardless of the position of the rotor, the Hall elements 64U, 64V,
The output of 64 W will not be the same. Therefore, the presence or absence of a failure can be determined by detecting the same output as described below.

FIG. 9 shows a circuit configuration included in the control device 70. A 64V signal is applied to this circuit at 64V,
64W is previously inverted. Here, the Hall element 64V is inverted as described above, but instead of the inverted arrangement, an output inverting circuit may be connected to the Hall element 64V.

Here, when the signals of the Hall elements 64U and 64W are low, no signal is input to the bases of the transistors TR1 and TR3, so that the potential via the resistors R1 and R5 becomes Flow to R6, amplifier IV
The outputs of 1, IV3 go high.

On the other hand, when the signals of the Hall elements 64U and 64W switch from low to high, the transistors TR1 and T1
The potential via the resistors R1 and R5, to which no signal is input to the base side of R3, flows to the resistors R4 and R6, and the amplifier IV
The output of 1, IV3 goes low. At this time, the Hall element 6
Since the 4V signal switches from high to low, the signal output from the amplifier IV2 changes from low to high. Thereby, regardless of the position of the rotor, the amplifiers IV1 and I1
The outputs from V2 and IV3 will not be the same.

On the other hand, if a failure occurs in the detection device 62, a disconnection of the signal line 65 in FIG.
Since this is equivalent to eliminating the sensor side circuit, the resistance R
The potentials of R1, R2, and R3 remain unchanged as resistances R4, R5, and R6.
And the outputs from all the amplifiers IV1, IV2, IV3 are high and identical. Based on this, the failure, disconnection, and forgetting to insert are detected.

FIG. 8 is a flowchart showing a routine for detecting a failure of the control device 70. The control circuit 70 determines whether or not the electric vehicle has been started (S12). here,
When an ignition key for enabling power supply to the wheel motor 10 of the electric vehicle is operated (S12)
Is Yes), three Hall elements 64U of the detection device 62,
It is determined whether the outputs of 64V and 64W are the same (S14).
Here, the failure of the detection device 62, the signal line 65 shown in FIG.
The output is not sent from the Hall elements 64U, 64V, 64W due to the disconnection of the connector 66, forgetting to insert the connector 66, etc., and when the outputs are the same (Yes in S14), the warning lamp is turned on (S18). For this reason, in the present embodiment, if there is any trouble before the electric vehicle starts running, the running can be postponed. For example, even when the connector 66 is forgotten during the inspection of the electric vehicle, the inspection can be performed again before the start of traveling based on the lighting of the warning or the like.

In this embodiment, since the three Hall elements 64U, 64V and 64W are arranged integrally so that the electrical angle becomes 60 degrees, they are arranged so that the electrical angle becomes 120 degrees. The size and weight of the detection device 62 can be reduced as compared with the case of FIG. Therefore, the unsprung weight of the wheel motor can be reduced, and the traveling performance can be improved. Further, in the detection device 62 of the present embodiment, the three centrally located Hall elements 64V are replaced with the other two Hall elements 64U, 6U.
Since the output of the center Hall element 64V is inverted by mounting the detection direction opposite to 4W, the configuration can be simplified. Although the Hall element is used as the magnetic detection sensor in the first embodiment, various magnetic detection sensors such as a magnetic thin film can be used.

Next, a wheel motor according to a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the ring magnet 95 magnetized on the north pole and the south pole is attached to the rotor hub 29 of the motor 24. On the other hand, in the second embodiment, the rotor hub 2
An extension 29b is provided on the motor 9 itself to detect the position of the motor 24.

FIG. 10 shows the configuration of the wheel motor, and FIG. 11 shows a view of the rotor hub 29 in FIG. The rotor hub 29 is provided with a groove 29a in a circumferential shape, and the groove 29a is provided at a position corresponding to the N pole of the first embodiment.
A pair of extending portions 29b facing each other is provided. Here, the detection device 162 includes a Hall element 164U.
In addition, a magnet 178 is provided, and a pair of extending portions 29b are provided at positions where the magnet 178 is provided as shown in FIG.
Is approaching, a magnetic path M is formed via the extending portion 29b, and the Hall element 164U detects this.

As shown in FIG. 11, the extending portion 29b is disposed at a mechanical angle of 60 degrees (electrical angle of 360 degrees), and although not shown, the three Hall elements 164U and 16
4V and 164W are arranged at a mechanical angle of 10 degrees (electrical angle of 60 degrees). Here, unlike the first embodiment, the central Hall element 164V of the detection device 162 is not arranged inverted.

Instead, in the second embodiment, as shown in FIG. 12, the output signal of the Hall element 164V at the center position is inverted by the inverter 80 and input to the control device 70. Therefore, similarly to the detection device 62 of the first embodiment, the outputs of the Hall elements 164U, 164V, and 164W do not become the same regardless of the position of the rotor.

In the second embodiment, the detection directions of the Hall elements are the same, but the control device 70 is controlled via the inverter 80 which inverts the output signal from the central Hall element.
Since the input is made to all the outputs, it is possible to prevent all outputs from being equal. In addition, the detecting device 162 is provided with a magnetic path M by alternately disposing the groove 29a and the pair of extending portions in the rotor hub 29.
Since a signal can be output depending on the presence or absence of the ring magnet 95, there is an advantage that it is not necessary to use the ring magnet 95 which is difficult to assemble.

[0042]

As described above, according to the first aspect of the present invention, since the outputs of all the magnetic detection sensors are prevented from being equal, it is possible to detect that the outputs of the magnetic detection sensors are equal. It is possible to determine a failure of the detection device, disconnection of a cable of the detection device, disconnection of a connector, and the like.

According to the second aspect of the present invention, since the three magnetic detection sensors are integrally provided so that the electrical angle becomes 60 degrees, the size and weight of the detection device can be reduced. In addition, since the output of the magnetic detection sensor at the center position among the three magnetic detection sensors is inverted, the outputs of the magnetic detection sensors do not become equal, and failure of the detection device, disconnection of the cable of the detection device, It becomes possible to detect disconnection of the connector and the like.

According to the third aspect of the present invention, since the three magnetic detection sensors at the center position are mounted in the opposite directions to the other two magnetic detection sensors, the configuration can be simplified.

According to the fourth aspect of the present invention, since the output is inverted by connecting an output inverting device to the three magnetic detection sensors at the center, even when the detection directions of the magnetic detection sensors are the same, In addition, the outputs of the magnetic detection sensors can be prevented from being equal.

According to the fifth aspect of the present invention, since the three magnetic detection sensors are integrally disposed so that the electrical angle becomes 60 degrees, the size and weight of the detection device can be reduced. Therefore, the unsprung weight of the wheel motor can be reduced. Further, since the output of the magnetic detection sensor at the center position among the three magnetic detection sensors is inverted, the outputs of the magnetic detection sensors do not become equal. For this reason,
The alarm device can issue an alarm before starting when the outputs of the three magnetic detection sensors are the same.

[Brief description of the drawings]

FIG. 1 is a sectional view of a wheel motor according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the wheel motor shown in FIG.

FIG. 3 is a view of the ring magnet in FIG.

4 (A) is a front view of the detection device as viewed from the side A in FIG. 2, and FIG. 4 (B) is a view of the detection device of FIG. FIG. 4 (C) is an enlarged view of a cycle C portion in FIG. 4 (A).

FIG. 5 is an explanatory diagram of a wheel motor and a control device.

FIG. 6 is a waveform chart showing outputs of three Hall elements arranged at an electrical angle of 60 degrees.

FIG. 7 is a waveform diagram showing outputs of three Hall elements which are arranged at an electrical angle of 60 degrees and the Hall elements at the center are inverted.

FIG. 8 is a flowchart illustrating a failure detection process performed by the control device.

FIG. 9 is a circuit diagram of an output conversion circuit in the control device.

FIG. 10 is a sectional view of a wheel motor according to a second embodiment of the present invention.

FIG. 11 is a view of the rotor hub shown in FIG.

FIG. 12 is a block diagram illustrating signal processing according to the second embodiment.

[Explanation of symbols]

Reference Signs List 10 wheel motor 11 drive device case 24 motor 25 stator 27 rotor 29 rotor hub 29b extension 62 detection device 70 control device (warning device) 64U, 64V, 64W Hall element (magnetic detection sensor) 80 inverter (reversing device) 95 ring magnet

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaharu Niimi 10 Takane, Fujii-machi, Anjo, Aichi Prefecture Inside Aisin AW Co., Ltd. (72) Inventor Yutaka Hotta 10 Takane, Fujii-machi, Anjo-shi, Aichi Aishi (72) Inventor Hideo Nakamura 10th Takane, Fujii-machi, Anjo-shi, Aichi F-term (reference) 3D035 DA02 3D039 AA05 AB01 AC24 AC25 AD11 3D042 AA06 AA10 AB01 BE01 BE02 5H115 PA00 PC06 PG04 PU11 RB08 SE03 TB01 TO30 TR05 TU20 TZ07 UI32 5H560 AA08 BB04 BB12 DA02 EB07 RR10

Claims (5)

[Claims] 1. A detection device for magnetically detecting a rotation angle of a motor, comprising: three or more magnetic detection sensors arranged at a predetermined electric angle and binaryly detecting the strength of a magnetic field; A detection device comprising: a reversing device for reversing an output of at least one magnetic detection sensor among the detection sensors; and an output device for outputting a sensor abnormality when outputs of all the magnetic detection sensors are equal. 2. A detection device for magnetically detecting a rotation angle of a motor, and a detection device for magnetically detecting a rotation angle of the motor so that an electric angle with respect to a magnetic pole to be detected is 60 degrees. Three magnetic detection sensors for detecting the intensity of the magnetic field, a reversing device for reversing the output of the magnetic detection sensor at the center position among the three magnetic detection sensors, and a case where the outputs of the three magnetic detection sensors are equal And an output device for outputting a sensor abnormality. 3. The reversing device is characterized in that the three magnetic detection sensors at the center position are configured to generate different outputs in the same magnetic flux direction with respect to the other two magnetic detection sensors. The detection device according to claim 2, wherein 4. The detecting device according to claim 2, wherein the reversing device is an inverter element provided at an output terminal of each of the three magnetic detection sensors at the central position. 5. An electric vehicle of a wheel motor type, wherein three magnetic detection sensors are disposed so that an electric angle becomes 60 degrees with respect to a polarity to be detected, and the intensity of a magnetic field is detected in a binary manner. A reversing device for reversing the output of the magnetic detection sensor at the center position of the three magnetic detection sensors, and an alarm device for issuing an alarm when the outputs of the three magnetic detection sensors are the same; An electric vehicle comprising: