JP2002340512A - Steering sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a steering sensor having a configuration, that can be arranged near a steering mechanism for reducing the slight deviations between rotary angle information detected by the steering sensor and the rolling steering angle of a wheel, for eliminating restrictions in the arrangement of other pieces of equipment around the steering wheel, and for reducing the risk of being strident on one's ears in a room, due to mechanical noise being generated from the steering sensor. SOLUTION: The steering wheel 21 is connected to a steering mechanism section 23 via a steering shaft 22; the operation of the steering wheel 21 by a driver for rotation causes the rotation to be transmitted to the steering mechanism section 23, that performs rolling steering of a wheel. The steering shaft 22 has a plurality of connection sections 24. At the connection section between the steering shaft 22 indicated by a symbol 25 and the steering mechanism section 23, a permanent magnet (not shown) is arranged on the end face of the tip section of the steering shaft 22. Then, the steering sensor 31 is arranged at a position that faces the permanent magnet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering angle sensor for generating a rotation angle of a steering device of an automobile.

[0002]

2. Description of the Related Art As a prior art of a steering angle sensor for generating a rotation angle of a steering device of an automobile, for example, JP-A-2000-283704 and JP-A-2000-283 are known.
A technique disclosed in Japanese Patent Application Laid-Open No. 705/705 or the like is known.
In the prior art described above, the steering angle sensor is incorporated in a rotary connector device with a built-in steering angle sensor, and is disposed near the steering wheel.

[0003]

A general automobile steering apparatus has a structure in which a steering wheel in a vehicle compartment and a steering mechanism in an engine room are connected by a steering shaft. Therefore, while the rotation of the steering wheel is transmitted to the steering mechanism, the rotation passes through at least the connection between the steering wheel and the steering shaft and the connection between the steering shaft and the steering mechanism. Also, generally, since a steering shaft is also provided with several connecting portions, there are a plurality of connecting portions between the steering wheel and the steering mechanism.

[0004] For this reason, a slight deviation occurs between the rotation angle of the steering wheel and the steering angle of the wheel by the steering mechanism due to backlash or the like of the respective connecting portions, whereby the vicinity of the steering wheel is reduced. There is a possibility that a slight shift may occur between the rotation angle information of the steering wheel detected by the conventional steering angle sensor disposed in the vehicle and the steering angle of the wheel. Therefore, considering that the original purpose of the steering angle sensor is to detect the steering angle of the wheel, it is desirable that the steering angle sensor be disposed as close to the steering mechanism as possible. And the slight deviation that occurs between the rotation angle information detected by the vehicle and the steering angle of the wheel can be reduced.

However, the steering angle sensor according to the prior art described above is arranged near the steering wheel in a state where the steering angle sensor is incorporated in a rotary connector device with a built-in steering angle sensor. It is very difficult to dispose a steering angle sensor near the vehicle.

Further, disposing the steering angle sensor near the steering wheel also has a problem that the arrangement of other devices around the steering wheel is restricted.

[0007] Further, the mechanical sound generated from the steering angle sensor disposed near the steering wheel disposed in the vehicle compartment may be annoying in a quiet vehicle compartment. .

The present invention has been made in view of such a situation, and an object thereof is to realize a steering angle sensor having a configuration that can be disposed near a steering mechanism, and a rotation angle detected by the steering angle sensor. In addition to reducing the slight deviation between the information and the steering angle of the wheels, the restriction on the arrangement of other devices around the steering wheel has been eliminated, and the mechanical noise generated by the steering angle sensor is annoying in the passenger compartment. This is to reduce the risk of being felt.

[0009]

According to a first aspect of the present invention, there is provided a steering apparatus comprising a steering wheel and a steering mechanism for steering the wheels connected by a steering shaft. A steering angle sensor for generating rotation angle information of the steering wheel, a permanent magnet having a substantially disc shape disposed on an end face of a tip of the steering shaft on a side of the steering mechanism, and a rotation of the permanent magnet A first magnetic flux detecting element that converts a change in the generated magnetic flux into an electric signal and outputs it as a first magnetic flux direction change waveform, and is disposed at a different angle from the first magnetic flux detecting element, and is generated by rotation of the permanent magnet. A second magnetic flux detecting element for converting a change in magnetic flux into an electric signal and outputting the electric signal as a second magnetic flux direction change waveform A, and a MR element as disposed in the steering mechanism to face the permanent magnet, a steering angle sensor characterized by.

As described above, the permanent magnet constituting the steering angle sensor is disposed on the end surface of the steering shaft on the side of the steering mechanism, and similarly, the M which constitutes the steering angle sensor is provided.
By disposing the R element in the steering mechanism so as to face the permanent magnet, it is possible to provide a configuration in which the steering angle sensor can be disposed near the steering mechanism.

[0011] Thus, the steering angle sensor is less likely to be affected by backlash or the like of a plurality of connecting portions between the steering wheel and the steering mechanism. In addition, the problem of disposing a steering angle sensor near the steering wheel to restrict the arrangement of other devices around the steering wheel is solved. further,
Since the steering angle sensor can be arranged in the engine room, the mechanical noise generated from the steering angle sensor is less likely to be harsh in a quiet vehicle interior.

Thus, according to the steering angle sensor according to the first aspect of the present invention, since the steering angle sensor can be disposed in the vicinity of the steering mechanism, the rotation angle information detected by the steering angle sensor and the wheel angle information can be obtained. The slight deviation between the steering angle and the steering angle is reduced, the restriction on the arrangement of other devices around the steering wheel is eliminated, and the mechanical noise generated from the steering angle sensor is less likely to cause harshness in the passenger compartment. The operation and effect can be obtained.

According to a second aspect of the present invention, there is provided a steering angle sensor for generating rotation angle information of the steering wheel of a steering device constituted by connecting a steering wheel and a steering mechanism for steering a wheel by a steering shaft. A permanent magnet having a substantially disc shape disposed on an end face of a motor shaft tip of a power steering motor whose rotation is controlled in accordance with the rotation of the steering wheel, and a magnetic flux generated by rotation of the permanent magnet. A first magnetic flux detection element that converts the change into an electric signal and outputs the first magnetic flux direction change waveform, and a change in magnetic flux that is arranged at an angle different from that of the first magnetic flux detection element and that is generated by rotation of the permanent magnet Into an electric signal and output as a second magnetic flux direction change waveform
And a MR element disposed at a position facing the permanent magnet.

In general, a power steering motor is provided in an engine room of an automobile, and its motor shaft is connected to a steering mechanism. Therefore, in this way, the permanent magnet constituting the steering angle sensor is disposed on the end face of the tip of the motor shaft of the power steering motor, and the MR element constituting the steering angle sensor is disposed at a position facing the permanent magnet. By doing so, a configuration is possible in which the steering angle sensor can be disposed near the steering mechanism.

Thus, according to the steering angle sensor according to the second aspect of the present invention, similarly to the first aspect of the present invention, the steering angle sensor has a configuration that can be disposed near the steering mechanism, thereby enabling the steering angle sensor to be disposed. In addition to reducing the slight deviation between the rotation angle information detected by the angle sensor and the steering angle of the wheel, the restriction on the arrangement of other devices around the steering wheel is eliminated, and the mechanical mechanism generated from the steering angle sensor The effect of being able to reduce the possibility that unpleasant sounds are unpleasant in the vehicle interior is obtained.

According to a third aspect of the present invention, a steering wheel and a steering mechanism for steering the wheels are mechanically separated from each other, and a driving means for driving the steering mechanism and a rotation angle of the steering wheel are provided. Control means for controlling the driving means in accordance with information;
A steering angle sensor for detecting a steering angle of the steering mechanism of the steering device, comprising: a collation unit configured to detect a steering angle of the steering mechanism and collate the rotation angle information of the steering wheel. A substantially magnet-shaped permanent magnet disposed at the center of the shaft, and a first magnetic flux detecting element for converting a change in magnetic flux generated by rotation of the permanent magnet into an electric signal and outputting the electric signal as a first magnetic flux direction change waveform And a second magnetic flux detecting element that is arranged at a different angle from the first magnetic flux detecting element, converts a change in magnetic flux generated by rotation of the permanent magnet into an electric signal, and outputs the electric signal as a second magnetic flux direction change waveform. And a MR element disposed at a position facing the permanent magnet.

The steering wheel and a steering mechanism for steering the wheels are mechanically separated from each other.
In a steering device in which a steering mechanism is motor-controlled in accordance with a rotation angle of a steering wheel and a wheel is steered, it is indispensable to collate the steering angle of the steering mechanism with the rotation angle of the steering wheel. The steering angle sensor having the same configuration as the steering angle sensor of the steering wheel detects the steering angle of the wheel by the steering mechanism by the steering angle sensor that can be disposed near the steering mechanism according to the present invention. Can be collated with the rotation angle of.

Thus, according to the steering angle sensor according to the third aspect of the present invention, in a steering device in which the steering wheel and the steering mechanism are mechanically separated from each other, the wheel of the steering mechanism is used. The operational effect is obtained that the means for comparing the steering angle and the rotation angle of the steering wheel can be configured relatively easily.

[0019] The invention described in claim 4 of the present application provides claims 1 to
3. In any one of the first to third aspects, the MR element may include the first element.
A magnetic flux component generated by the first magnetic flux generating means disposed inside the magnetic flux detecting element is superimposed on the first magnetic flux direction change waveform and output as a third magnetic flux direction change waveform, and the second magnetic flux A configuration in which a magnetic flux component generated by a second magnetic flux generating means disposed inside the detection element is superimposed on the second magnetic flux direction change waveform and output as a fourth magnetic flux direction change waveform; By performing a comparison operation between the magnetic flux direction change waveform and the second magnetic flux direction change waveform, 0 °
A rotation angle of about 180 °, and a fifth magnetic flux direction change waveform obtained by subtracting the fourth magnetic flux direction change waveform from the third magnetic flux direction change waveform.
And the sixth magnetic flux direction change waveform obtained by adding the third magnetic flux direction change waveform and the fourth magnetic flux direction change waveform, the rotation angle becomes 0 °. Rotation angle in the region of ~ 180 ° or 18
It is determined whether the rotation angle is in the range of 0 ° to 360 °, and when it is determined that the rotation angle is in the range of 180 ° to 360 °, a rotation angle of 180 ° is added to the rotation angle. With one permanent magnet and one MR element,
A steering angle sensor having a configuration capable of generating 360 ° absolute rotation angle information of the steering wheel.

A first magnetic flux direction change waveform due to a change in the magnetic flux direction of the permanent magnet and an MR element having a magnetic flux generating means such as an electromagnetic coil therein and two magnetic flux detecting elements arranged at different angles are provided. In addition to the second magnetic flux direction change waveform, it is possible to generate a third magnetic flux direction change waveform and a fourth magnetic flux direction change waveform on which a change component of the magnetic flux direction due to an electromagnetic coil or the like is superimposed. By comparing the third magnetic flux direction change waveform with the fourth magnetic flux direction change waveform, the rotation calculated by comparing the first magnetic flux direction change waveform with the second magnetic flux direction change waveform is calculated. Whether the angle is a rotation angle in the range of 0 ° to 180 °,
It is possible to determine whether the rotation angle is in the range of 180 ° to 360 °. And thereby one M
With the R element, it is possible to generate 360 ° absolute rotation angle information.

Thus, according to the steering angle sensor according to the fourth aspect of the present invention, in addition to the effect of the invention according to any one of the first to third aspects of the present invention, one MR is provided.
It is possible to realize a steering angle sensor that can generate absolute rotation angle information of the steering wheel with the element, thereby enabling further miniaturization and cost reduction of the steering angle sensor and increasing the failure rate. The operation and effect that a low steering angle sensor can be realized is obtained.

According to a fifth aspect of the present invention, in accordance with the fourth aspect, the steering angle sensor is configured such that the steering angle sensor is based on a previously stored reference rotation position of the steering wheel.
A steering angle sensor having means for calculating and generating absolute rotation angle information of the steering wheel exceeding 0 °.

Thus, according to the steering angle sensor according to the fifth aspect of the present invention, in addition to the operation and effect according to the fourth aspect of the present invention, the reference rotation position of the steering wheel is set in advance. By having a means for calculating and calculating the absolute rotation angle information of the steering wheel from the reference rotation position and the 360 ° absolute rotation angle information generated from the output of the MR element,
The operation and effect that the absolute rotation angle information of the steering wheel exceeding 0 ° can be generated is obtained.

[0024] The invention described in claim 6 of the present application relates to claims 1 to
A steering apparatus for an automobile, comprising the steering angle sensor according to any one of Claims 5 to 5. According to the steering apparatus for an automobile according to the invention described in claim 6 of the present application, the operation and effect of the invention described in any one of the above-described claims 1 to 5 can be obtained in the steering apparatus for an automobile.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a steering device provided with a steering angle sensor according to the present invention.

The steering wheel 21 is connected to a steering mechanism 23 via a steering shaft 22. When the driver operates and rotates the steering wheel 21, the steering mechanism 2 is rotated.
The rotation is transmitted to 3, and by the steering mechanism 23,
Wheels not shown are steered. The steering shaft 22 has a plurality of connecting portions 24 as shown.

In the connection portion between the steering shaft 22 and the steering mechanism 23 indicated by the reference numeral 25, the end surface of the distal end portion of the steering shaft 22 has
A permanent magnet (not shown) is provided. A steering angle sensor 31 according to the present invention is disposed at a position facing the permanent magnet as shown in the figure.

FIG. 2 is a schematic perspective view of the steering angle sensor 31 according to the present invention. The steering angle sensor 31 includes a main body 311
And an electronic circuit board 312 on which an MR element (magnetic resistance element) 15 is mounted. The body 311 has three mounting holes 313 for mounting. MR element 1
Reference numeral 5 denotes an element that outputs a change in the magnetic flux direction of a permanent magnet disposed to face the steering angle sensor 31 as a change in voltage value. Hereinafter, the MR element 15 will be described, and then a process of generating the absolute rotation angle information of the steering wheel 21 in the steering angle sensor 31 including the MR element 15 will be described with reference to the drawings.

Further, as described above, the permanent magnet disposed at the tip of the steering shaft 22 is disposed at a position facing the MR element 15 mounted on the steering angle sensor 31. Therefore, there is no mechanical part that generates sliding noise such as a gear. Therefore,
The steering angle sensor 31 according to the present embodiment does not generate any mechanical sound.

FIG. 3 schematically shows the structure of the MR element 15 provided in the steering angle sensor 31 according to the present invention. The MR element 15 has two magnetic flux detecting elements, a first magnetic flux detecting element 1 and a second magnetic flux detecting element 2. These two magnetic flux detecting elements are:
They are arranged at different angles, and as shown, the angle is about 45 °. On the magnetic flux direction detecting surface of the MR element 15, a permanent magnet (not shown)
By rotating in conjunction with the rotation of the
The magnetic flux direction W on the magnetic flux direction detecting surface of the above changes. First magnetic flux detecting element 1 and second magnetic flux detecting element 2
Detects the change in the magnetic flux direction W, converts it into an electric signal, and outputs it. Here, V1 indicates the output voltage of the first magnetic flux detection element 1, and V2 indicates the output voltage of the second magnetic flux detection element 2.

The first magnetic flux detecting element 1 has a built-in first electromagnetic coil 3 as a magnetic flux generating means, and the second magnetic flux detecting element 2 has a second electromagnetic coil 3 as a magnetic flux generating means. 4 built-in. When the first electromagnetic coil 3 and the second electromagnetic coil 4 are energized, the first electromagnetic coil 3 generates a magnetic flux in the direction of the arrow indicated by reference numeral B1, and the second electromagnetic coil 4 , Code B2
A magnetic flux is generated in the direction of the arrow shown by. Note that Vv indicates the power supply voltage of the first magnetic flux detecting element 1 and the second magnetic flux detecting element 2.

FIG. 4 is a graph showing a first magnetic flux direction change waveform and a second magnetic flux direction change waveform output by the MR element 15 provided in the steering angle sensor 31 according to the present invention.

Since the first magnetic flux detecting element 1 and the second magnetic flux detecting element 2 are arranged at different angles, they output voltage signals having waveforms having different phases. here,
Assuming that the voltage waveform of the first magnetic flux direction change waveform output by the first magnetic flux detection element 1 is Vsin and the voltage waveform of the second magnetic flux direction change waveform output by the second magnetic flux detection element 2 is Vcos, Vsin And the voltage waveform of Vcos is shown in FIG.
The voltage waveform shown in FIG. In the graph shown in the figure, the vertical axis indicates the output voltage of the magnetic flux detecting element, and the horizontal axis indicates the angle α in the magnetic flux direction. Since the first magnetic flux detecting element 1 and the second magnetic flux detecting element 2 are arranged with a 45 ° angle shift, the output voltage waveforms of Vsin and Vcos have a 45 ° phase shift. . Further, the waveforms of Vsin and Vcos from 0 ° to 180 °, and 1
The waveforms of Vsin and Vcos from 80 ° to 360 ° are the same.

Therefore, the absolute rotation angle information of the steering wheel 21 that can be generated by comparing and calculating the two magnetic flux direction change waveforms whose phases are shifted is 0 °.
Up to 180 °. As can be seen from the graph of FIG. 11, the absolute rotation angle information of the steering wheel 21 that can be generated by comparing and calculating two magnetic flux direction change waveforms having different phases is 0 ° to 360 ° per rotation.
This is because a rotation angle of 180 ° and a rotation angle of 180 ° to 360 ° become the same rotation angle information and cannot be distinguished.

FIG. 5 is a graph showing a third magnetic flux direction change waveform and a fourth magnetic flux direction change waveform output by the MR element 15 provided in the steering angle sensor 31 according to the present invention.

As described above, the first magnetic flux detecting element 1 has the first electromagnetic coil 3 as the first magnetic flux generating means inside, and the second magnetic flux detecting element 2
A second electromagnetic coil 4 as a second magnetic flux generating means therein
have. By energizing the first electromagnetic coil 3 and the second electromagnetic coil 4, the first magnetic flux detecting element 1 and the second magnetic flux detecting element 2 have electromagnets inside. And thereby, the first
Output the third magnetic flux direction change waveform in which the magnetic flux of the permanent magnet and the magnetic flux generated by the magnetic field generated by the first electromagnetic coil 3 are superimposed. A fourth magnetic flux direction change waveform in which the magnetic flux of the magnet and the magnetic flux generated by the magnetic field generated by the second electromagnetic coil 4 are superimposed is output.

Here, assuming that the voltage waveform of the third magnetic flux direction change waveform is ΔVsin and the voltage waveform of the fourth magnetic flux direction change waveform is ΔVcos, the voltage waveforms of ΔVsin and ΔVcos are shown in the graph of FIG. It becomes a voltage waveform. As described above, ΔVsin is a magnetic flux B1 (FIG. 3) in a direction that is a fixed reference with respect to the direction W (FIG. 3) of the magnetic flux changed by the rotation of the permanent magnet due to the magnetic field generated by the first electromagnetic coil 3. ) Is superimposed. Also, ΔVco
Similarly, s is a magnetic flux B2 (FIG. 3) in a fixed reference direction with respect to the direction W of the magnetic flux changed by the rotation of the permanent magnet due to the magnetic field generated by the second electromagnetic coil 4.
Are superimposed on each other.

The magnetic fluxes B1 and B generated when the first electromagnetic coil 3 and the second electromagnetic coil 4 are energized.
2 is a very small magnetic flux level as compared with the magnetic flux W generated by the permanent magnet. Therefore, the voltage waveforms of ΔVsin and ΔVcos shown in FIG. 3 are voltage waveforms obtained by amplifying only the superimposed component by the electromagnetic coil.

As described above, the first magnetic coil 3 and the second magnetic coil 4 built in the first magnetic flux detecting element 1 and the second magnetic flux detecting element 2 serve as a reference in a certain direction. It is possible to obtain voltage waveforms of ΔVsin and ΔVcos in which the magnetic flux directions are superimposed. The process of generating 360 ° absolute rotation angle information in one MR element 15 provided in the steering angle sensor 31 according to the present invention from the voltage waveforms of ΔVsin and ΔVcos will be described below.

FIG. 6 shows a fifth magnetic flux direction change waveform obtained by subtracting the voltage waveform of ΔVcos from the voltage waveform of ΔVsin, and ΔVsin.
13 is a graph showing a sixth magnetic flux direction change waveform obtained by adding the voltage waveform of ΔVcos to the voltage waveform of FIG.

A fifth magnetic flux direction change waveform ΔVsin− is obtained by subtracting the voltage waveform ΔVcos from the voltage waveform ΔVsin.
The voltage waveform of ΔVcos is such that the angle α in the magnetic flux direction is 0 ° to 16 °.
Until the vicinity of 0 °, the region having a positive voltage value changes, and from around 160 ° to approximately 340 °, the region of a negative voltage value changes.
In the range up to °, a graph of a voltage waveform changes again in a region having a positive voltage value. On the other hand, a voltage waveform of ΔVsin + ΔVcos as a sixth magnetic flux direction change waveform obtained by adding the voltage waveform of ΔVsin and the voltage waveform of ΔVcos has a region having a positive voltage value and a region having a negative voltage value as shown in the drawing. It becomes a graph of a voltage waveform that changes alternately. Then, the voltage waveform of L1 shown in FIG. 7 is generated from the voltage waveform of ΔVsin−ΔVcos, and the voltage waveform of L2 shown in FIG. 8 is generated from the voltage waveform of ΔVsin + ΔVcos.

FIG. 7 is a graph showing a voltage waveform L1 generated from the voltage waveform of ΔVsin−ΔVcos. The voltage waveform L1 is obtained by performing arithmetic processing on the voltage waveform of ΔVsin−ΔVcos shown in FIG. 6, converting all positive voltage values to a constant negative voltage value with a voltage value of 0 V as a boundary, and converting all negative voltage values to a constant value. Is a voltage waveform converted into a positive voltage value.

FIG. 8 is a graph showing a voltage waveform L2 generated from the voltage waveform of ΔVsin + ΔVcos. The voltage waveform L2 is the same as the voltage waveform L1, as shown in FIG.
This is a voltage waveform obtained by performing arithmetic processing on a voltage waveform of + ΔVcos, converting all positive voltage values to a constant positive voltage value with a voltage value of 0 V as a boundary, and converting all negative voltage values to a constant negative voltage value. .

FIG. 9 shows a voltage waveform L3 generated from the voltage waveform L1 and the voltage waveform L2. Voltage waveform L
In FIG. 1, the point of voltage change is that the angle α in the magnetic flux direction is 16
A point near 0 ° and a point where the angle α in the magnetic flux direction is near 340 °. On the other hand, in the voltage waveform L2, the voltage value at the point where the angle α in the magnetic flux direction is around 160 ° is a negative voltage value, and the voltage value at the point where the angle α in the magnetic flux direction is around 340 ° is a positive voltage value. It is. That is, in a range of 0 ° to 360 °, a voltage waveform L1 having two voltage change points having an interval of about 180 ° and a voltage waveform L2 having different voltage polarities at the two voltage change points are calculated by an arithmetic process. The voltage waveform L3 can be generated.

The voltage waveform L3 has an angle α in the magnetic flux direction of 0 °.
It has a constant positive voltage value in the region of 180 ° to 180 °, and has a constant negative voltage value in the region of 180 ° to 360 ° in the magnetic flux direction. That is, it is possible to determine from the voltage waveform L3 whether the angle α in the magnetic flux direction is in the range of 0 ° to 180 ° or in the range of 180 ° to 360 °. Therefore, Vsin and Vc
It is possible to generate 360 ° absolute rotation angle information from the absolute rotation angle information from 0 ° to 180 ° based on the voltage waveform of os and the voltage waveform L3.

FIG. 10 is a graph showing the relationship between the absolute rotation angle information from 0 ° to 180 ° based on the voltage waveforms of Vsin and Vcos and the angle α in the magnetic flux direction. Thus, 0
The absolute rotation angle (vertical axis of the graph) that can be generated by calculating from the voltage waveforms of Vsin and Vcos with respect to the angle α (horizontal axis of the graph) in the magnetic flux direction from ° to 360 ° is 0 to 180 °. . Therefore, the angle α of the magnetic flux direction is 0 ° to 180 °.
And the graph from 180 ° to 360 ° are the same graph.

Therefore, from the voltage value of the voltage waveform L3 described above, when the angle α in the magnetic flux direction is an angle between 180 ° and 360 °, that is, when the voltage value of the voltage waveform L3 is negative, The absolute rotation angle information from 0 ° to 180 ° based on the voltage waveforms of Vsin and Vcos shown in FIG.
By adding 180 °, 36 shown in FIG.
It is possible to generate absolute rotation angle information of 0 °.

As described above, the steering angle sensor 31 shown in the present embodiment has a configuration capable of generating 360 ° absolute rotation angle information by a combination of one permanent magnet and one MR element 15. I have. Then, the steering angle sensor 3 can be disposed in the steering mechanism 23.
1 reduces the slight deviation between the rotation angle information detected by the steering wheel 1 and the steering angle of the wheel, eliminates the restriction on the arrangement of other devices around the steering wheel 21, and generates a mechanism generated from the steering angle sensor 31. This makes it possible to reduce the possibility that a typical sound is harsh in the vehicle interior.

As another embodiment, a steering wheel 21 having a combination of one permanent magnet and one MR element 15 as described above and having a reference rotation position of the steering wheel 21 stored in advance as a reference is provided. Which has a means for calculating and generating the absolute rotation angle information.

This means that a combination of one permanent magnet and one MR element 15 can generate 360 ° absolute rotation angle information, and can also use the reference rotation position of the steering wheel 21 stored in advance as a reference. By calculating and generating absolute rotation angle information of the steering wheel 21, it is possible to generate absolute rotation angle information exceeding 360 °. As a result, the steering angle sensor 31 capable of generating absolute rotation angle information of the steering wheel 21 exceeding 360 ° can be configured, and the function and effect according to the present invention can be obtained in the steering angle sensor 31.

Further, as another embodiment, a steering device having a power steering device in which a steering angle sensor 31 is provided on a motor shaft 22 of a power steering motor is provided.

FIG. 12 shows a steering angle sensor 31 according to the present invention.
FIG. 1 is a perspective view showing a schematic configuration of a steering device equipped with a power steering device provided with a power steering device.

As with the steering device shown in FIG.
The steering wheel 21 includes the steering shaft 2
The rotation is transmitted to the steering mechanism 23 by the driver operating the steering wheel 21 to rotate the steering wheel 21, and the steering mechanism 23 does not show the rotation. The wheels steer. The steering shaft 22 has a plurality of connecting portions 24 as shown. A power steering motor 26 is connected to the steering shaft 22 as shown in the figure. The power steering motor 26 is driven and controlled in accordance with the operation of the steering wheel 21 by the driver, and rotates the steering shaft 22. On the motor shaft of the power steering motor 26, a permanent magnet (not shown) is provided, and at a position facing the permanent magnet,
A steering angle sensor 31 according to the present invention is provided as shown.

Since the motor shaft of the power steering motor 26 rotates in conjunction with the rotation of the steering shaft 22, the steering wheel connected to the steering shaft 22 is provided by disposing the steering angle sensor 31 on the motor shaft. 21 absolute rotation angle information can be generated. Therefore, the steering angle sensor 31 is attached to the motor shaft of the power steering motor 26.
By arranging the power steering device, the present invention can be implemented, and the above-described operation and effect of the present invention can be obtained in a steering device equipped with such a power steering device.

Further, as shown in FIG.
A steering angle sensor 31 is provided at a connection portion between the steering shaft 22 and the steering mechanism 23, and the steering angle sensor 31 provided on the motor shaft of the power steering motor 26 is used as a rotation detection sensor of the power steering motor 26. It is also possible to adopt a configuration used for other purposes.

Further, as another embodiment, a steering apparatus in which a steering wheel 21 and a steering mechanism section 23 are mechanically separated from each other and a steering angle sensor 31 according to the present invention is mounted on the steering apparatus. No.

FIG. 13 shows a steering angle sensor 31 according to the present invention.
FIG. 1 is a perspective view showing a schematic configuration of a steering device in which a steering wheel 21 provided with a steering mechanism 21 and a steering mechanism 23 are mechanically separated.

The steering device shown in this embodiment has a steering wheel 21 and a steering mechanism 2
3 is not mechanically connected. The steering wheel 21 is provided with a steering angle sensor 31a as shown. The steering mechanism 23 is provided with a steering angle sensor 31b as shown. Steering angle sensor 31a
Is electrically connected to the control unit 28, generates a rotation angle of the steering wheel 21, and outputs the rotation angle to the control unit 28. The steering angle sensor 31b is electrically connected to the control unit 28, generates a rotation angle of the steering shaft 22, and outputs the rotation angle to the control unit 28. A steering drive motor 27 is provided on the steering shaft 22 as a drive unit of the steering mechanism 23. The steering drive motor 27 is connected to the control unit 2.
8 and is drive-controlled by the control unit 28. A steering angle sensor 31c is provided on the motor shaft of the steering drive motor 27 as shown in the figure.

The control unit 28 calculates the steering angle of the wheel from the rotation angle of the steering wheel 21 output from the steering angle sensor 31a, and controls the rotation of the steering drive motor so that the wheel has the calculated steering angle. have.
The control unit 28 also controls the rotation angle of the steering wheel 21 output from the steering angle sensor 31a and the steering angle sensor 31b.
And a collation means for comparing the rotation angle of the steering shaft 22 output by the controller with the collation means. Control unit 2
8 compares the rotation angle of the motor shaft generated by the steering angle sensor 31c with the rotation angle of the steering wheel 21 generated by the steering angle sensor 31b to determine whether the steering drive motor 27 is abnormal or the steering drive motor 27 Failure detecting means for detecting a failure or the like in a connection portion between the steering shaft 22 and the steering shaft 22 is also provided.

In the steering device having such an embodiment, the steering angle sensor 31 shown in FIG.
a and the steering angle sensor 31b. Since the outputs of the steering angle sensors 31 having the same configuration are compared with each other, it is possible to relatively easily configure a means for checking the turning angle of the wheels by the steering mechanism unit 31 and the rotation angle of the steering wheel 21. It is obtained.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the invention described in the claims, which are also included in the scope of the present invention. Needless to say,

[0062]

According to the present invention, a steering angle sensor having a configuration that can be disposed near the steering mechanism is realized, and the rotation angle information is generated between the rotation angle information detected by the steering angle sensor and the steering angle of the wheel. This makes it possible to reduce the slight displacement, to eliminate the restriction on the arrangement of other devices around the steering wheel, and to reduce the possibility that the mechanical sound generated from the steering angle sensor is harsh in the vehicle interior.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a steering device provided with a steering angle sensor according to the present invention.

FIG. 2 is a schematic perspective view of a steering angle sensor according to the present invention.

FIG. 3 schematically shows a configuration of an MR element provided in the steering angle sensor according to the present invention.

FIG. 4 is a graph showing a first magnetic flux direction change waveform and a second magnetic flux direction change waveform output by an MR element provided in the steering angle sensor according to the present invention.

FIG. 5 is a graph showing a third magnetic flux direction change waveform and a fourth magnetic flux direction change waveform output by the MR element provided in the steering angle sensor according to the present invention.

6 is a graph showing a sixth magnetic flux direction change waveform obtained by adding a fifth magnetic flux direction change waveform obtained by subtracting a ΔVcos voltage waveform from a ΔVsin voltage waveform, a ΔVsin voltage waveform, and a ΔVcos voltage waveform; FIG. It is.

FIG. 7 is a graph showing a voltage waveform L1 generated from a voltage waveform of ΔVsin−ΔVcos.

FIG. 8 is a graph showing a voltage waveform L2 generated from a voltage waveform of ΔVsin + ΔVcos.

FIG. 9 shows a voltage waveform L3 generated from the voltage waveform L1 and the voltage waveform L2.

FIG. 10 shows 0 ° to 180 ° according to voltage waveforms of Vsin and Vcos.
9 is a graph showing a relationship between absolute rotation angle information up to ° and an angle α in a magnetic flux direction.

FIG. 11 is a graph showing a relationship between 360 ° absolute rotation angle information and an angle α of a magnetic flux direction.

FIG. 12 is a perspective view showing a schematic configuration of a steering device equipped with a power steering device provided with a steering angle sensor according to the present invention.

FIG. 13 is a perspective view showing a schematic configuration of a steering device in which a steering wheel provided with a steering angle sensor according to the present invention and a steering mechanism are mechanically separated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st magnetic flux detection element 2 2nd magnetic flux detection element 3 1st electromagnetic coil 4 2nd electromagnetic coil 11 Steering shaft 12 1st gear 13 Permanent magnet 14 2nd gear 15 MR element 16 Reduction gear 21 Steering Wheel 22 steering shaft 23 steering mechanism unit 24 connecting unit 26 power steering motor 27 steering drive motor 28 control unit 31 steering angle sensor W magnetic flux direction α angle in magnetic flux direction B1 magnetic flux direction generated by first electromagnetic coil B2 second Direction of magnetic flux generated by the electromagnetic coil

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Ishimasa 5-2931, Urago-cho, Yokosuka-shi, Kanagawa Prefecture F-term in Bosch Brake System Co., Ltd. (reference) 2F063 AA36 BA08 BB03 BC04 BD16 CA23 CA40 DA01 DB07 DD02 DD03 DD08 EA03 GA29 GA52 GA58 LA11 LA22 LA23 ZA01 2F077 AA20 AA49 JJ01 JJ06 JJ09 JJ23 TT06 TT52 3D033 CA29

Claims (6)

[Claims] 1. A steering angle sensor for generating rotation angle information of a steering wheel of a steering device configured by connecting a steering wheel and a steering mechanism for steering a wheel with a steering shaft, wherein: A permanent magnet having a substantially disk shape disposed on the end face of the steering mechanism side end and converting a change in magnetic flux generated by rotation of the permanent magnet into an electric signal and outputting the electric signal as a first magnetic flux direction change waveform; A first magnetic flux detecting element and a magnetic flux change element arranged at an angle different from that of the first magnetic flux detecting element, converting a change in magnetic flux generated by rotation of the permanent magnet into an electric signal and outputting the electric signal as a second magnetic flux direction change waveform. Two magnetic flux detecting elements, and are disposed in the steering mechanism so as to face the permanent magnet. And a MR element, a steering angle sensor characterized by. 2. A steering angle sensor for generating rotation angle information of a steering wheel of a steering device configured by connecting a steering wheel and a steering mechanism for steering a wheel by a steering shaft, A permanent magnet having a substantially disk shape disposed on the end face of the motor shaft tip of the power steering motor whose rotation is controlled in accordance with the rotation, and converting a change in magnetic flux generated by rotation of the permanent magnet into an electric signal, A first magnetic flux detection element that outputs a first magnetic flux direction change waveform, and a first magnetic flux detection element that is arranged at a different angle from the first magnetic flux detection element, converts a change in magnetic flux generated by rotation of the permanent magnet into an electric signal, A second magnetic flux detection element that outputs a second magnetic flux direction change waveform,
A steering angle sensor, comprising: an MR element disposed at a position facing the permanent magnet. 3. A steering mechanism for mechanically separating a steering wheel and a steering mechanism for steering wheels, wherein the driving means for driving the steering mechanism and the driving means in accordance with rotation angle information of the steering wheel are provided. A steering angle sensor for detecting a steering angle of the steering mechanism of a steering device, comprising: a control unit for controlling; and a collation unit for detecting a steering angle of the steering mechanism and collating with rotation angle information of the steering wheel. A permanent magnet having a substantially disk shape disposed at the center of the rotation axis of the steering wheel, and converting a change in magnetic flux generated by rotation of the permanent magnet into an electric signal and outputting the electric signal as a first magnetic flux direction change waveform. A first magnetic flux detecting element, the magnetic flux detecting element being disposed at a different angle from the first magnetic flux detecting element; An MR element that has a second magnetic flux detecting element that converts a change in magnetic flux generated by rotation of the magnet into an electric signal and outputs the electric signal as a second magnetic flux direction change waveform, and an MR element disposed at a position facing the permanent magnet; A steering angle sensor comprising: 4. The method according to claim 1, wherein
The MR element superimposes a magnetic flux component generated by a first magnetic flux generating means disposed inside the first magnetic flux detecting element on the first magnetic flux direction change waveform to form a third magnetic flux direction change waveform. And outputting a fourth magnetic flux direction change waveform by superimposing a magnetic flux component by the second magnetic flux generation means disposed inside the second magnetic flux detection element on the second magnetic flux direction change waveform. The rotation angle of 0 ° to 180 ° is calculated by comparing the first magnetic flux direction change waveform and the second magnetic flux direction change waveform, and the third magnetic flux direction change waveform is formed. And a sixth magnetic flux direction change waveform obtained by adding the third magnetic flux direction change waveform and the fourth magnetic flux direction change waveform to each other. By performing a comparison operation on It is determined whether the rotation angle is a rotation angle in a range of 0 ° to 180 ° or a rotation angle in a range of 180 ° to 360 °, and is determined to be a rotation angle in the range of 180 ° to 360 °. When the rotation angle is 1
By adding a rotation angle of 80 °, one permanent magnet and one MR element have a configuration capable of generating 360 ° absolute rotation angle information of the steering wheel. Rudder angle sensor. 5. The steering angle sensor according to claim 4,
A steering angle sensor comprising: means for calculating and generating absolute rotation angle information of the steering wheel exceeding 360 ° based on a reference rotation position of the steering wheel stored in advance. 6. A steering apparatus for an automobile, comprising the steering angle sensor according to claim 1. Description: