JP2002357452A - Rotation sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation sensor capable of measuring rotation angle and torque with a single sensor and reducing the weight. SOLUTION: In this rotation sensor, a case 4 cooperates with first and second rotors 2 and 3 to form an annular space S inside. In the annular space S, a base board 5 having first and second electric conductors 5a-5f formed on the surface and turning with the first rotor 2, a first holding member 1 holding first brushes 6a and 6b, which are brought into contact with the first electric conductors 5a and 5b for detecting information accompanying the rotation of the first and second rotors as a voltage change, and a second holding member 7 holding second brushes 7a-7d, which are brought into contact with the second electric conductors 5c-5f for detecting information accompanying the rotation of the first and second rotors 2 and 3 as a voltage change, are arranged respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a rotation sensor.

[0002]

2. Description of the Related Art In recent years,
With increasing interest in global environmental issues, research on weight reduction of a vehicle body has been advanced as one of measures to reduce the exhaust gas of an automobile. In order to reduce the weight of the vehicle body, for example, it has been studied to use an electric power steering device and eliminate the need for a hydraulic pump used for achieving appropriate power assist by operating mechanical parts with a hydraulic pump. I have.

[0003] However, if the power steering device is of an electric type, a rotation sensor, that is, a steering angle sensor for measuring a steering angle associated with a steering operation and a torque sensor for measuring a torque are required because the assist force is calculated by a computer. Become. Therefore, in the case of an electric power steering device, two parts, a steering angle sensor and a torque sensor, are required in spite of aiming for weight reduction, and there is a problem that the number of components increases.

[0004] The rotation sensor is disposed over two rotation shafts, for example, a steering shaft and a column shaft connected via a torsion bar in the case of an automobile. In a steering device of an automobile, since the steering shaft and the column shaft are connected via a torsion bar, the axial centers of the steering shaft and the column shaft may be shifted. For this reason, in a rotation sensor that is connected via a torsion bar and used for an object in which two rotation axes are likely to be displaced, such as a steering device, the offset is absorbed, and the accuracy of detecting information accompanying rotation is improved. There is a need for measures to suppress the decline.

Further, some rotation sensors detect a torque and a rotation angle by using a brush and an electric conductor. However, brushes and electrical conductors that come into contact with each other have a high frictional resistance, so organic gas in the air causes a mechanochemical reaction at the frictional portion between the brush and the electrical conductors, forming an insulating film and causing unexpected electrical This may lead to an increase in resistance.

[0006] Such an increase in electric resistance can be avoided by setting a large contact force of the brush with the electric conductor in advance. However, in this case, there is a problem that the durability of the electric conductor is reduced, the output signal becomes unstable, and the rotation sensor cannot be used for a long time. On the other hand, the rotation sensor is provided with a countermeasure for monitoring an abnormal signal. However, as a result of the fluctuation of the abnormal signal due to vibration, there has been a problem that a signal abnormality cannot be properly detected.

It is a first object of the present invention to provide a rotation sensor capable of measuring a rotation angle and a torque with a single sensor and reducing the weight. I do. In addition to the above-described first object, the present invention provides a rotation mechanism capable of absorbing the axial deviation even when the axis centers of the two rotational axes are deviated, and suppressing a decrease in detection accuracy of information due to the rotation. A second object is to provide a sensor.

It is a third object of the present invention to provide a rotation sensor that can be used for a long period of time by improving the durability of an electric conductor and stabilizing an output signal. A fourth object of the present invention is to provide a rotation sensor capable of stabilizing the abnormal signal.

[0009]

According to the present invention, in order to achieve the above object, first and second rotors rotatably assembled to each other, and a case for rotatably holding the first and second rotors. Wherein the first and second rotors are attached to a first rotation shaft and a second rotation shaft connected via a torsion bar, respectively, and rotate integrally, and the first rotation shaft Is a rotation sensor that makes a relative rotation within a predetermined angle corresponding to a relative rotation with respect to the second rotation axis, wherein the case cooperates with the first and second rotors to form an annular inside. A plurality of first and second electric conductors are formed on the surface of the annular space, respectively, and a substrate that rotates integrally with the first rotor and a first electric conductor that contacts the first electric conductor, respectively. And the first
And a first holding member that holds a first brush that detects information accompanying a rotation of a second rotor as a change in voltage, and a first holding member that holds the first brush, and supplies the first brush with the second electric conductor. And a second holding member for holding a second brush that detects information accompanying the rotation of the second rotor as a change in voltage.

Preferably, the second rotor and the first rotor
Is elastically connected to the holding member by an elastic connecting member. Also preferably, the elastic connecting member includes at least two first elastic pieces attached to the substrate,
And at least two second elastic pieces attached to the rotor, and having a cross section perpendicular to the first and second rotation axes, having a quadrangle formed by an inertia axis with respect to a cut surface of each of the first and second elastic pieces. Is formed.

[0011] More preferably, the square is a rectangle. Preferably, the substrate has a configuration in which the first electric conductor is formed on one surface and the second electric conductor is formed on the other surface. Also preferably, the first electric conductor has a slip ring for transmitting a torque signal and a slip ring for detecting torque, and the second electric conductor has a slip ring for supplying power, and a slip ring for supplying ground power. It has a slip ring, a slip ring for detecting a steering angle, and a slip ring for transmitting a torque signal.

More preferably, the slip ring for transmitting a torque signal, the slip ring for detecting a torque, the slip ring for detecting a steering angle, and the slip ring for transmitting a torque signal have low frictional resistance and have conductivity. The slip ring for power supply and the slip ring for ground power supply are covered with a synthetic resin, and are formed on the innermost side in the radial direction.

[0013] Preferably, the first electric conductor is arranged in a range of a predetermined central angle of the substrate, and a voltage is applied so that a phase is reversed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a rotation sensor according to the present invention will be described below. For example, the rotation sensor is disposed across a steering shaft and a column shaft of an automobile connected via a torsion bar, and is provided with a rudder associated with a steering operation. The rotation sensor for measuring the angle and the torque will be described in detail with reference to FIGS.

The rotation sensor 1 achieves the first and second objects of the present invention. As shown in FIGS. 1 and 3, first and second rotors 2 and 3, a case 4, a substrate 5, A holding plate 6, a fixed substrate 7 and a coupling member 8 are provided.
The first rotor 2 is rotatably assembled with the second rotor 3 as shown in FIGS. 1 and 3, and is attached to a steering shaft (not shown). The second rotor 3 has a flange 3a (see FIG. 3) protruding radially inward at a lower portion, and is attached to a column shaft (not shown). Here, the first rotor 2 and the second rotor 3 rotate integrally with the rotation axis Art shown in FIGS. 1 and 3, and correspond to the rotation of the steering shaft relative to the column shaft. Relative rotation within a predetermined angle.

The case 4 is, as shown in FIGS. 1 and 3,
It has an upper case 4a and a lower case 4b, and forms an annular space S (see FIG. 3) inside in cooperation with the first and second rotors 2, 3. In the space S, a substrate 5, a holding plate 6, a fixed substrate 7, and a coupling member 8, which will be described later, are arranged. Substrate 5
Is attached to the outer periphery of the lower end of the first rotor 2 and rotates integrally with the first rotor 2. The substrate 5 is, as shown in FIG.
A slip ring 5a for torque detection and a slip ring 5b for transmitting a torque signal, serving as a first electric conductor, are provided on the lower surface.
Each is formed on a concentric circle having a different radius from the inner peripheral side. The substrate 5 has a power supply slip ring 5c, a steering angle detection slip ring 5d, and a ground power supply slip ring 5e serving as a second electric conductor on the upper surface.
And a slip ring 5f for transmitting a torque signal are formed on concentric circles having different radii from the inner peripheral side.
Among these, the electric conductors constituting the slip rings 5a and 5d have a predetermined resistance value set in advance. A predetermined voltage is applied to each of the slip rings 5a to 5f according to the purpose. For example, as shown in FIG. 5, the slip ring 5d for detecting the steering angle has 0 volt at the point A,
When a voltage of V volts is applied to point B, the voltage between points A and B changes in direct proportion to the length x along the circumferential direction according to the principle of a potentiometer. That is, when the first rotor 2 rotates integrally with the substrate 5, the length x along the circumferential direction of the slip ring 5 d with which the brush 7 b described below contacts is changed, and the first ring 2 has a voltage corresponding to the length x as the first voltage. The rotation angle of the rotor 2 is detected.

Here, the slip rings 5a to 5f can be formed, for example, by metal plating. The holding plate 6 is a first holding member formed in a disk shape, and has a brush 6a for torque detection and a brush 6b for transmitting a torque signal on its upper surface as shown in FIG. Brush 6
Reference numerals a and 6b denote first brushes that are electrically connected to the slip rings 5a and 5b, respectively, and detect information accompanying rotation of the first and second rotors 2 and 3 as a change in voltage. In particular, the torque detecting brush 6a detects a voltage corresponding to an angle difference caused by the relative rotation of the first and second rotors 2, 3. The voltage corresponding to the angle difference detected in this manner is applied to the brush 6a → the slip ring 5a → the slip ring 5e → the brush 7c → the torque signal output cable 1d described later, and the brush 6b → the slip ring 5b.
→ Slip ring 5f → Brush 7d to be described later → Torque signal output cable 1d to be described later, and output to external processing unit 11 (see FIG. 1). At this time,
The arithmetic processing device 11 calculates the rotation angles of the rotors 2 and 3 in the rotation sensor 1 and the torque associated with the relative rotation based on the signals output from the angle signal output cable 1b and the torque signal output cable 1d. Electronic circuits or microcomputer chips are used.

The fixed substrate 7 includes an upper case 4a and a lower case 4
b, and a disk serving as a second holding member, a brush 7a for power supply and a brush 7 for angle detection
b, a brush 7c for supplying ground power and a brush 7d for transmitting torque signals are held in this order from the inner peripheral side to the outer peripheral side. The brushes 7a to 7d are second brushes that are in contact with and electrically connected to the slip rings 5c to 5f, respectively, and detect information accompanying rotation of the first and second rotors 2 and 3 as a change in voltage. The brushes 7a to 7d are respectively connected to the power cable 1 shown in FIG.
a, an angle signal output cable 1b, a ground power supply input cable 1c, and a torque signal output cable 1d are connected.

The coupling member 8 is formed of a metal such as stainless steel or a plastic such as PBT (polybutylene terephthalate), and is an elastic connecting member for elastically connecting the second rotor 3 and the holding plate 6. As shown in FIGS. 2 to 4, the coupling member 8 has a ring-shaped main body 8.
The two first elastic pieces 8b and the two second elastic pieces 8c are respectively arranged on the outer periphery of a. The first elastic piece 8b and the second elastic piece 8c are arranged at a central angle of 90 degrees. However, the coupling member 8 shown in FIG. 3 has a cross section in which the right half side and the left half side are shifted by 90 degrees, and the first elastic piece 8b
And the second elastic piece 8c.

The first elastic piece 8b has two screw holes 8d on the distal end side, is formed so as to be bent outward in the radial direction and protruded outward, and is screwed to the inner peripheral upper surface of the holding plate 6. Is done. The second elastic piece 8c has two screw holes 8e on the distal end side, is formed so as to be curved inward in the radial direction and is projected inward, and is screwed to the lower surface of the flange 3a.

By configuring the coupling member 8 as described above, the coupling member 8 has high rigidity in the direction in which the holding plate 6 rotates,
The rigidity is low with respect to the displacement of the rotors 2 and 3 in the direction of the plate surface perpendicular to the rotation axis Art. For this reason, the coupling member 8 is moved from the column shaft (not shown) to the second rotor 3.
Can be absorbed while transmitting the rotation transmitted to the holding plate 6 to the steering shaft (not shown) and the column shaft (not shown).

However, the coupling member 8 is not essential for the rotation sensor 1 because it has a function of absorbing an axial deviation between the steering shaft and the column shaft (not shown) as described above. Therefore, in the rotation sensor 1 configured as described above, when the steering shaft is rotating within a predetermined torque, the torque is transmitted to the column shaft via a torsion bar, and the steering shaft is rotated. And the column shafts and thus the rotors 2, 3 rotate integrally. On the other hand, when the steering shaft rotates beyond a predetermined torque, a rotational deviation occurs between the steering shaft and the column shaft,
The first rotor 2 and the second rotor 3 relatively rotate within a predetermined angle.

In each rotation situation as described above, the rotation sensor 1 outputs an angle signal and a torque signal from the angle signal output cable 1b and the torque signal output cable 1d. And the torque associated with the relative rotation are calculated. Here, the elastic connecting member is a coupling member 1 shown in FIGS.
0, punch out and bend a square plate made of metal such as stainless steel, and stand up from the plate surface.
A structure in which the two first elastic pieces 10a and the two second elastic pieces 10b are formed so as to face the outer edge side, respectively, and the portion shown by oblique lines in FIG. Then, the coupling member 10 is screwed to the lower surface of the flange 3a of the second rotor 3 with the connecting piece 10d and to the inner peripheral upper surface of the holding plate 6 with the connecting piece 10e. With such a structure, the coupling member 10 can be connected to the coupling member 8.
It is easier and cheaper to manufacture.

On the other hand, the rotation sensor 1 which achieves the third object of the present invention uses a substrate 15 shown in FIG. On the lower surface of the substrate 15, a slip ring 15a for torque detection and a slip ring 15b for transmitting a torque signal, which are first electric conductors, are formed on concentric circles having two different radii from the outer peripheral side. Also, the substrate 15
Is a ground power supply slip ring 15c and a power supply slip ring 1c serving as a second electric conductor on the upper surface.
5d, a slip ring 15e for detecting a steering angle and two slip rings 15f for transmitting a torque signal are formed on concentric circles having different radii from the inner peripheral side. Therefore, regarding the second electric conductor, the ground power supply slip ring 15c and the power supply slip ring 15d are formed on the innermost side in the radial direction.
Then, among the slip rings 15a to 15f, a slip ring 15a for torque detection, a slip ring 15b for transmitting a torque signal, and a slip ring 15 for steering angle detection.
e and two slip rings 15f for transmitting torque signals
Is coated with a synthetic resin 16 such as an epoxy resin mixed with conductive carbon having low frictional resistance. Here, the slip ring 15c for supplying the ground power and the slip ring 15d for supplying the power are not covered with the synthetic resin 16 to avoid a voltage drop.

Therefore, the rotation sensor 1 using the substrate 15
Since the brush contacts the corresponding slip ring via the synthetic resin 16, the mechanochemical reaction is prevented from occurring, and the contact force of the brush does not need to be set large. For this reason, the rotation sensor 1 using the substrate 15 improves the durability of the slip rings 15a, 15b, 15e, and 15f, stabilizes the output signal, and can be used for a long time.

Further, the rotation sensor 1 which achieves the fourth object of the present invention uses a substrate 17 shown in FIGS. 9 and 10 in which the substrate 15 shown in FIG. 8 is modified. That is, the substrate 17 is provided with the slip ring 15 which is the first electric conductor on the substrate 15.
A and 15b are arranged within a predetermined central angle range of the substrate 17, like the slip ring 17a for torque detection and the slip ring 17b for transmitting a torque signal shown in FIGS. The slip rings 17a and 17b arranged adjacent to the center in the radial direction are electrically connected to the brush 6a for torque detection and the brush 6b for torque signal transmission, respectively, and the reference position P0 of the ground (0V) is shown in the figure. Thus, the voltage is set at different positions in the circumferential direction, and the voltage is applied so that the phases are opposite.

Here, the substrate 17 has on its upper surface a slip ring 17c for supplying ground power, which serves as a second electric conductor,
A slip ring 17d for supplying power, a slip ring 17e for detecting a steering angle, and two slip rings 17f for transmitting a torque signal are formed on concentric circles having different radii from the inner peripheral side. Further, the substrate 17 is formed by combining a slip ring 17e for detecting a steering angle and two slip rings 17f for transmitting a torque signal with a phenol-based resin or the like mixed with conductive carbon having low frictional resistance. The resin 18 is covered.

The substrate 17 includes slip rings 17a, 17
b is arranged in this manner, and the ground (0V) reference position P
By setting 0 as described above, the abnormal signal can be stabilized. That is, in the board 15 shown in FIG. 8, as described in FIG. 5, the voltage of the electric signal detected by the brush 6a for torque detection and the brush 6b for transmitting the torque signal is equal to the voltage of the first and second rotors 2, Due to the relative rotation of 3, the slip rings 15a, 15b increase or decrease as shown in FIG. 11 corresponding to the length along the circumferential direction from the reference position P0 of the slip rings 15a, 15b with which the brushes 6a, 6b are in contact.

Here, in FIG. 11, the horizontal axis is the relative rotation angle, the vertical axis is the voltage (V) of the electric signal detected by the brushes 6a and 6b, and 0 on the horizontal axis is the first of the rotation sensor 1.
And at a neutral position in the relative rotation of the second rotors 2 and 3,
The same applies to FIGS. 13 to 16. At this time, in order to detect an abnormal signal, for example, the substrate 19 shown in FIG.
, The slip rings 19a, 19b are
And the reference position P0 of the ground (0 V) is set so that the phase of the output signal is reversed. When the first and second rotors 2 and 3 rotate relative to each other on the substrate 19, the electric signal detected by a brush (not shown) in contact with the slip ring 19a changes in voltage as shown by T1 in FIG. The electric signal detected by a brush (not shown) in contact with the slip ring 19b has a voltage of FIG.
It changes like T2 of 3. Therefore, if the signal T3 obtained by adding the two electric signals T1 and T2 is monitored, an abnormal signal can be monitored.

That is, if an abnormal signal Tir1 shown in FIG. 14 is generated to one of the two electric signals T1 and T2, the same abnormal signal Tir3 is added to the signal T3 obtained by adding the electric signals T1 and T2. appear. At this time, if the substrate 19 rattles due to vibration, as shown in FIG. 15, the electric signals T1 and T2 detected by the brush (not shown) generate distortions Td1 and Td2 accompanying the rattling. As a result, even if the distortions Td1 and Td2 of the electric signals T1 and T2 are within the normal range, the signal T3 is monitored for the distortion Td3 added twice as shown in the figure, and is regarded as an abnormal signal. I will.

Therefore, the rotation sensor 1 which achieves the fourth object of the present invention uses the substrate 17 shown in FIGS. 9 and 10. That is, the substrate 17 has the slip rings 17a and 17b arranged within a predetermined central angle range, and the slip rings 17a and 17b arranged adjacent to the center in the radial direction.
b is ground (0) so that the phase of the output signal is reversed.
The reference position P0 of V) is set at a different position in the circumferential direction.

Therefore, by using the substrate 17,
In the rotation sensor 1, since the phases of the electric signal T1 and the electric signal T2 are opposite, the phases of the distortions Td1 and Td2 of the electric signals T1 and T2 are also opposite. As a result, the signal T3 obtained by adding the electric signals T1 and T2 becomes the distortion Td1 of the electric signal T1 as shown in FIG.
And the distortion Td2 of the electric signal T2 are offset and stabilized, and even if the abnormal signal fluctuates, the signal abnormality can be properly detected.

The rotation sensor according to the above-described embodiment is arranged over the steering shaft and the column shaft of the automobile, and measures the steering angle and the torque associated with the operation of the steering wheel. However, the rotation sensor of the present invention can be used for any type of sensor such as a robot arm as long as it determines the rotation angle and torque between two rotating shafts that rotate with each other.

[0034]

According to the first to fourth aspects of the present invention, the rotation angle and the torque can be measured by one sensor, the weight can be reduced, and the center of the two rotating shafts to be mounted is shifted. However, it is possible to provide a rotation sensor that can achieve the first and second objects of the present invention, which can absorb the axial deviation and can suppress a decrease in information detection accuracy due to rotation.

According to the fifth and sixth aspects of the present invention, the first
Since the second electric conductor and the second electric conductor are formed on different surfaces, the number of substrates can be reduced to one, and the first object of the present invention of simplifying the structure and reducing the weight of the rotation sensor can be achieved. Further, according to the invention of claim 7, the durability of the electric conductor is improved to achieve the stability of the output signal,
A rotation sensor that achieves the third object of the present invention, which can be used for a long time, can be provided.

According to the eighth aspect of the present invention, it is possible to provide a rotation sensor which can stabilize an abnormal signal and achieve the fourth object of the present invention.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a rotation sensor which achieves first and second objects of the present invention.

FIG. 2 is a perspective view of an elastic member used in the rotation sensor of FIG.

FIG. 3 is a sectional front view of the rotation sensor of FIG. 1 cut along a diameter;

FIG. 4 is a cross-sectional view of the rotation sensor of FIG. 3 taken along line AA.

FIG. 5 is an explanatory diagram illustrating a principle of detecting a rotation angle of a first rotor based on a length of a slip ring.

FIG. 6 is a perspective view showing another embodiment of the elastic member.

FIG. 7 is a sectional view corresponding to FIG. 4 of a rotation sensor using the elastic member of FIG. 6;

FIG. 8 is a sectional view of a substrate used in a rotation sensor that achieves a third object of the present invention.

FIG. 9 is a sectional view of a substrate used in a rotation sensor that achieves a fourth object of the present invention.

FIG. 10 is a perspective view showing the first electric conductor by inverting the substrate of FIG. 9;

FIG. 11 is a voltage characteristic diagram showing a relationship between a relative rotation angle associated with a relative rotation of a rotation sensor and a voltage of an electric signal detected by a brush.

FIG. 12 shows a configuration in which a slip ring is disposed opposite to a rotation center, and a substrate in which the phase of an output signal is set to be reversed is inverted to form a first ring.
FIG. 3 is a perspective view showing the electric conductor of FIG.

FIG. 13 shows a rotation sensor using the substrate of FIG.
FIG. 4 is a voltage characteristic diagram showing a relationship between a relative rotation angle and a voltage of an electric signal detected by a brush.

FIG. 14 is a voltage characteristic diagram corresponding to FIG. 13 when an abnormal signal occurs.

FIG. 15 is a voltage characteristic diagram showing a relationship between a relative rotation angle having distortion generated when the substrate of FIG. 12 is shaken by vibration and a voltage of an electric signal.

16 is a voltage characteristic diagram showing a relationship between a relative rotation angle and a voltage of an electric signal when the substrate of FIG. 9 is used.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Rotation sensor 2 1st rotor 3 2nd rotor 4 Case 5 Substrate 5a Slip ring for torque detection (1st electric conductor) 5b Slip ring for torque signal transmission (1st electric conductor) 5c Slip for power supply Ring (2nd
5d Slip ring for steering angle detection (second
5e Slip ring for ground power supply (second electric conductor) 5f Slip ring for transmitting torque signal (second electric conductor) 6 Holding plate (first holding member) 6a Torque detecting brush (First brush) 6b Brush for transmitting torque signal (first brush) 7 Fixed substrate (second holding member) 7a Brush for supplying power (second brush) 7b Brush for detecting angle (second brush) 7c Brush for ground power supply (second brush)
7d) Brush for transmitting torque signal (second brush) 8 Coupling member (elastic connecting member) 8b First elastic piece 8c Second elastic piece 10 Coupling member (elastic connecting member) 10a First elastic piece 10b Second elastic piece 11 Arithmetic processing unit 15 Substrate 15a Slip ring for torque detection (first electric conductor) 15b Slip ring for torque signal transmission (first electric conductor) 15c Slip ring for ground power supply (second 15d slip ring for power supply (second
15e Slip ring for steering angle detection (second
15f Slip ring for transmitting torque signal (second electric conductor) 17 Substrate 17a Slip ring for detecting torque (first electric conductor) 17b Slip ring for transmitting torque signal (first electric conductor) 19 Substrate 19a, 19b Slip ring C Rotation center P0 Reference position S Annular space

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshiro Yamamoto 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Inventor Hisaro Abe 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Inventor Masahiro Hasegawa 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Akira Noguchi 2-6-1 Marunouchi, Chiyoda-ku, Tokyo F-term in Furukawa Electric Co., Ltd. (Reference) 2F051 AA01 AB06 BA03 2F063 AA36 BA08 CA21 CA34 DA05 DD03 FA01 KA01 NA03 2F077 AA31 AA43 AA49 CC02 CC08 EE02 VV02 WW08 3D033 CA17

Claims (8)

[Claims] A first rotor and a second rotor rotatably assembled to each other; and a case rotatably holding the first and second rotors, wherein the first and second rotors include a torsion bar. The first rotation shaft and the second rotation shaft are connected to each other through the first rotation shaft and the second rotation shaft. The first rotation shaft rotates relative to the second rotation shaft. A rotation sensor that relatively rotates within a predetermined angle, wherein the case forms an annular space therein in cooperation with the first and second rotors, and the annular space has a surface First
And a plurality of second electric conductors are formed, respectively,
A first brush that holds a first brush that contacts the first electric conductor and a substrate that rotates together with the first rotor and detects information accompanying the rotation of the first and second rotors as a change in voltage; A second brush for holding a second brush that is in contact with a holding member and the second electric conductor to supply power or detect information accompanying rotation of the first and second rotors as a change in voltage; And a holding member. 2. The apparatus according to claim 2, wherein the second rotor and the first holding member are elastically connected by an elastic connecting member.
The rotation sensor according to claim 1. 3. The elastic connection member includes at least two first elastic pieces attached to the substrate and at least two second elastic pieces attached to the second rotor. 3. The rotation sensor according to claim 2, wherein a quadrangle is formed by an inertia axis with respect to a cut surface of each of the first and second elastic pieces in a cross section perpendicular to the second rotation axis. 4. 4. The rotation sensor according to claim 3, wherein said square is a rectangle. 5. The rotation according to claim 1, wherein the substrate has the first electric conductor formed on one surface and the second electric conductor formed on the other surface. Sensor. 6. The first electric conductor includes a slip ring for transmitting a torque signal and a slip ring for detecting a torque, and the second electric conductor includes a slip ring for supplying power and a ground ring for supplying power. The rotation sensor according to claim 5, further comprising a slip ring for detecting a steering angle and a slip ring for transmitting a torque signal. 7. A synthetic resin having a low frictional resistance and a conductive property for the slip ring for transmitting a torque signal, the slip ring for detecting a torque, the slip ring for detecting a steering angle, and the slip ring for transmitting a torque signal. 7. The rotation sensor according to claim 6, wherein the power supply slip ring and the ground power supply slip ring are formed on a radially innermost side. 8. The rotation sensor according to claim 5, wherein the first electric conductor is arranged in a range of a predetermined central angle of the substrate, and a voltage is applied so that a phase is reversed.