JP7090539B2 - Vehicle torque sensor - Google Patents

Description

The present disclosure relates to a vehicle torque sensor that measures torque applied to a rotating shaft having magnetostrictive characteristics.

The following Patent Document 1 proposes a technique of covering the outer peripheral side of a detection coil arranged around a rotating shaft with a shield portion in a magnetostrictive torque sensor for the purpose of reducing electromagnetic noise.

Japanese Patent No. 3065230

However, the torque sensor of Patent Document 1 has a problem that the hysteresis error of the torque sensor may increase due to the magnetic field generated in the shield portion.
One aspect of the present disclosure is to make it possible to suppress a hysteresis error while reducing electromagnetic noise in a vehicle torque sensor that measures torque applied to a rotating shaft having magnetostrictive characteristics.

One aspect of the present disclosure is a vehicle torque sensor that measures torque applied to a rotating shaft having magnetostrictive characteristics, and includes a plurality of detection coils, a measuring unit, a coil shield unit, and a magnetic ring. ..
The plurality of detection coils are configured by winding an insulated wire around the rotating shaft at a distance set in advance from the rotating shaft. The coil shield portion is formed of a material that suppresses the transmission of a magnetic field, and covers at least a part of a side surface portion that is an axial end surface of a rotation axis in a plurality of detection coils. The measuring unit measures the torque applied to the rotating shaft by detecting the change in inductance in the plurality of detection coils. The magnetic ring is arranged on the outer peripheral side of the plurality of detection coils and has a magnetic material formed in a hollow cylindrical shape. On the outer peripheral side of the magnetic ring, a member having a material that allows the transmission of a magnetic field is arranged.

According to such a configuration, electromagnetic noise can be reduced by covering the side surface portions of the plurality of detection coils with the shield portions. Further, according to such a configuration, the outer peripheral side of the magnetic ring is not covered with the member that blocks the transmission of the magnetic field, and the magnetic field generated by the member that blocks the transmission of the magnetic field on the outer peripheral side can be suppressed, so that the torque. The hysteresis error of the sensor can be suppressed.

It is an exploded perspective view of a torque sensor. It is a perspective view (part 1) of a torque sensor. It is a perspective view (2) of a torque sensor. It is sectional drawing when the torque sensor is attached to the axis of rotation. It is a perspective view of the torque sensor which attached the terminal shield part. It is a perspective view of the torque sensor after resin molding. It is a block diagram of a measuring part. It is a graph which shows the relationship between torque and sensor sensitivity. It is a graph which shows the relationship between torque and hysteresis error. It is a graph which shows the relationship between the torque and the degree of variation of a sensor sensitivity. It is a block diagram which shows the measuring apparatus. It is a graph which shows the influence of the magnetic field generated when the torque motor is operated in the torque sensor of an embodiment. It is a graph which shows the influence of the magnetic field generated when the torque motor is operated in the torque sensor of a reference example.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[1-1. Overall configuration of torque sensor]
FIG. 1 is an exploded perspective view of the torque sensor 1 of one aspect of the present disclosure. 2 and 3 are perspective views of the torque sensor 1 after assembly. FIG. 4 is a cross-sectional view when the torque sensor 1 is attached to the rotation shaft 2.

As shown in FIG. 4, the torque sensor 1 is a magnetostrictive type sensor that is attached around a rotating shaft 2 having a magnetostrictive characteristic and measures a rotational torque applied to an arbitrary rotating shaft 2 mounted on a vehicle. ..

As shown in FIGS. 1 to 4, the torque sensor 1 includes a magnetostrictive torque sensor coil 5, coil shield portions 6 and 7, a magnetic ring 8, a terminal holding portion 9, and a plurality of terminal portions 50. To prepare for. In FIG. 1, the description of the terminal holding portion 9 and the terminal portion 50 is omitted.

The magnetostrictive torque sensor coil 5 is also referred to as a first detection coil 30 and a second detection coil 35 (hereinafter, also referred to as “detection coils 30 and 35”) composed of a bobbin 20 and an insulated wire wound around the bobbin 20. ) And.

The rotating shaft 2 is made of a material having magnetostrictive characteristics, and is formed in a columnar shape, in other words, a rod shape. Examples of the material having magnetostrictive characteristics include nickel, iron-aluminum alloy, iron-cobalt alloy and the like.

As the material used for the rotating shaft 2, either a positive magnetostrictive material whose magnetic permeability decreases during compression and an increase in magnetic permeability during tension, or a negative magnetostrictive material whose magnetic permeability increases during compression and whose magnetic permeability decreases during tension is used. It doesn't matter. As the rotary shaft 2, for example, a shaft used for torque transmission of a power train system, a shaft used for torque transmission of a vehicle engine, or the like can be adopted.

The bobbin 20 is inserted into the hollow portion of the magnetic ring 8. Coil shield portions 6 and 7 are arranged on both side surfaces of the bobbin 20 along the axial direction L of the rotating shaft 2. In other words, the bobbin 20 is fixed to the magnetic ring 8 so as to be sandwiched between the coil shield portions 6 and 7.

As shown in FIG. 4, in the torque sensor 1, a gap is formed between the inner wall of the bobbin 20 and the rotating shaft 2. By forming a gap, the torque sensor 1 is configured so as not to come into contact with the rotating shaft 2. The bobbin 20 is provided so as to be separated from the rotating shaft 2 by a predetermined distance Δd, and is provided coaxially with the rotating shaft 2.

Further, since the torque sensor 1 is fixed to a fixing member such as a housing, it is configured not to rotate with the rotation of the rotating shaft 2.
Detection coils 30 and 35 are formed on the outer peripheral surface of the bobbin 20 by winding an insulated wire so as to be inclined by ± 45 degrees with respect to the axial direction L. The change in magnetic permeability when torque is applied to the rotating shaft 2 is greatest in the direction of ± 45 degrees with respect to the axial direction L. Therefore, the inclination of the insulated wire with respect to the axial direction L is set to ± 45 degrees. However, the angle at which the insulated wire is wound is not limited to ± 45 degrees with respect to the axial direction L, and may be any angle.

In the present embodiment, the detection coils 30 and 35 are formed on the outer peripheral surface of the bobbin 20. Therefore, it is preferable to use a bobbin 20 formed by using a material having a smaller influence on the magnetic flux generated by the detection coils 30 and 35 than the metal material, for example, a resin.

The magnetic ring 8 is made of a magnetic material, for example, a ferromagnetic material such as a dust core, and is formed in a hollow cylindrical shape. A bobbin 20 provided with detection coils 30 and 35 is inserted into the hollow portion of the magnetic ring 8, and the magnetic ring 8 is arranged so as to cover the outer peripheral surface of the bobbin 20.

The inner diameter of the magnetic ring 8 is substantially the same as the outer diameter of the bobbin 20, and is formed to be slightly larger than the outer diameter of the bobbin 20. The magnetic ring 8 plays a role of suppressing the magnetic flux generated by the detection coils 30 and 35 from leaking to the outside and lowering the sensitivity.

Here, in the torque sensor 1, a resin member (resin mold) 62 is arranged on the outer peripheral side of the plurality of detection coils 30 and 35 centered on the rotation shaft 2 and on the outer peripheral side of the magnetic ring 8. The resin member 62 is made of a synthetic resin or the like and allows the transmission of a magnetic field. In addition, not only the resin member 62 but also a material that allows the transmission of a magnetic field, for example, a non-metal such as air may be arranged on the outer peripheral side of the magnetic ring 8.

The "member made of a material that allows the transmission of a magnetic field" may contain a metal (an example of a material that suppresses the transmission of a magnetic field) within a range that allows the transmission of electromagnetic waves. Specifically, a material that suppresses the transmission of electromagnetic waves such as metal may be contained within a range in which characteristics such as sensitivity and hysteresis error of the detection coils 30 and 35 do not change.

The terminal holding portion 9 is arranged in contact with the coil shield portion 6 on one side of the coil shield portions 6 and 7. More specifically, the terminal holding portion 9 is arranged on the surface of the coil shield portion 6 opposite to the bobbin 20. The terminal holding portion 9 is configured in a ring shape having an outer diameter substantially matching the outer diameter of the magnetic ring 8 and an inner diameter substantially matching the inner diameter of the bobbin 20. A plurality of terminal portions 50 are connected to the terminal holding portion 9, and the plurality of terminal portions 50 are held by the terminal holding portion 9. In this embodiment, the two terminal portions 50 are held by the terminal holding portion 9. However, the number of the terminal portions 50 held by the terminal holding portions 9 may be one, or may be three or more. The terminal holding portion 9 is made of an insulating material, for example, a resin.

The terminal portion 50 is made of a conductive material, for example, a metal material, and is arranged so as to project from the outer peripheral side of the terminal holding portion 9. The terminal portion 50 is electrically connected to the insulated wires constituting the plurality of detection coils 30 and 35.

The coil shield portions 6 and 7 have a function of protecting the detection coils 30 and 35 from external electromagnetic noise (shielding electromagnetic noise (magnetic field and electric field)). The coil shield portions 6 and 7 are arranged in contact with the side surface portions 30A and 30B which are the end faces of the plurality of detection coils 30 and 35 on the L side in the axial direction.

The coil shield portions 6 and 7 of the present embodiment are formed of, for example, aluminum, which is a conductive material. The coil shield portions 6 and 7 may be formed of, for example, an alloy of aluminum and another metal material. The coil shield portions 6 and 7 may be made of any substance as long as it has a function of shielding electromagnetic noise.

The coil shield portion 6 on one side covers only the side surface portions 30A of the detection coils 30 and 35. That is, the coil shield portion 6 on one side has an outer diameter that substantially matches the inner diameter of the magnetic ring 8 and an inner diameter that roughly matches the arrangement surface 20A on which the insulated wires of the detection coils 30 and 35 are arranged in the bobbin 20. It is configured in a ring shape.

The coil shield portion 7 on the other side covers all of the side surface portions 30B of the detection coils 30 and 35, the end face of the bobbin 20, and the end face of the magnetic ring 8. That is, the coil shield portion 7 on the other side is configured in a ring shape having an outer diameter substantially matching the outer diameter of the magnetic ring 8 and an inner diameter substantially matching the inner diameter of the bobbin 20.

[1-2. Peripheral configuration of torque sensor]
In the torque sensor 1, the terminal unit 50 is electrically connected to the measuring unit 41 described later. The terminal unit 50 and the measurement unit 41 are connected by a shielded wire 53 as shown in FIGS. 5 and 6. However, the terminal portion 50 and the shielded wire 53 are connected via an insulated wire 52 extending from the shielded wire 53.

The insulated wire 52 constitutes the shielded wire 53 and is a coated conductor wire. The insulated wire 52 comprises a conductor and an insulating coating covering the conductor. The shielded wire 53 is formed by covering the periphery of a plurality of insulated wires 52 (four insulated wires 52 in this embodiment) with a structure (for example, SUS braid) that shields electromagnetic noise and a sheath. The insulated wire 52 extending from the shielded wire 53 is a portion of the insulated wire 52 exposed by removing the sheath and the structure that shields the above-mentioned electromagnetic noise from the shielded wire 53.

In the present embodiment, the terminal shielded portion 60 is provided around the terminal portion 50 and the insulated wire 52 extending from the shielded wire 53 in order to improve the resistance to electromagnetic noise.
The terminal shield portion 60 is made of a metal such as aluminum or an aluminum alloy having a function of shielding electromagnetic noise. As shown in FIG. 5, the terminal shield portion 60 covers at least the periphery of the terminal portion 50, and in the present embodiment, covers the periphery of the portion of the insulated wire 52 from the terminal portion 50.

As shown in FIG. 6, the torque sensor 1 in the state where the terminal shield portion 60 is arranged is resin-molded so that the entire torque sensor 1 is covered with the resin member 62. However, the shielded wire 53 is configured to extend outward from the resin member 62.

The torque sensor 1 thus resin-molded is arranged on the rotating shaft 2 and connected to the measuring unit 41 for use.
[1-3. Measurement unit configuration]
As shown in FIG. 7, the torque sensor 1 includes a measuring unit 41 that measures the torque applied to the rotation shaft 2 by detecting changes in the inductances of the first detection coil 30 and the second detection coil 35. There is. Hereinafter, the inductances of the pair of coils constituting the first detection coil 30 are L1 and L4, and the inductances of the pair of coils constituting the second detection coil 35 are L2 and L3.

The measuring unit 41 includes a bridge circuit 42, a transmitter 43, a voltage measuring circuit 44, and a torque calculation unit 45. The bridge circuit 42 is configured by sequentially connecting the detection coils 30 and 35 in an annular shape.

The transmitter 43 applies an AC voltage between the contact a between the detection coils 30 and 35 and the contact b between the detection coils 30 and 35. The voltage measuring circuit 44 detects the voltage between the contact c between the detection coils 30 and 35 and the contact d between the detection coils 30 and 35.

The torque calculation unit 45 calculates the torque applied to the rotating shaft 2 based on the voltage measured by the voltage measuring circuit 44. In the measuring unit 41, when no torque is applied to the rotating shaft 2, the inductances L1 to L4 of the detection coils 30 and 35 are equal, and the voltage detected by the voltage measuring circuit 44 is substantially 0.

Here, when torque is applied to the rotating shaft 2, the magnetic permeability in the +45 degree direction with respect to the axial direction L decreases or increases, and the magnetic permeability in the −45 degree direction with respect to the axial direction L increases or decreases. do. Therefore, when torque is applied to the rotating shaft 2 while the AC voltage is applied from the transmitter 43, the inductance of the first detection coil 30 decreases or increases, and the inductance of the second detection coil 35 increases or decreases. As a result, the voltage detected by the voltage measuring circuit 44 changes, and the torque calculation unit 45 calculates the torque applied to the rotation shaft 2 based on the change in the voltage.

Since the detection coils 30 and 35 of each layer have exactly the same configuration except that the winding directions are different, the influence of temperature on the inductance of the detection coils 30 and 35 is canceled by using the bridge circuit 42 as shown in FIG. This is possible, and the torque applied to the rotating shaft 2 can be detected with high accuracy. Further, in the torque sensor 1, if the inductance increases or decreases in the first detection coil 30, the inductance always decreases or increases in the second detection coil 35. Therefore, by using the bridge circuit 42 as shown in FIG. 7, detection is performed. The sensitivity can be further improved.

[1-4. Experimental result]
It was confirmed by experiments that the torque sensor 1 of the present embodiment has good characteristics. FIG. 8 is a graph showing the relationship between torque and sensor sensitivity, FIG. 9 is a graph showing the relationship between torque and hysteresis error, and FIG. 10 is a graph showing the relationship between torque and the degree of variation in sensor sensitivity.

The hysteresis error represents a relative reversibility error, that is, a difference in the characteristic curve obtained when the load is increased and when the load is decreased. The value of the hysteresis error is preferably small.

In this experiment, as shown in FIG. 4, various torque sensors including the torque sensor 1 of the present embodiment are mounted on a resin fixing base or an aluminum fixing base 65, and the rotation shaft 2 is mounted in the torque sensor. Was placed through. Then, by applying torque to the rotating shaft 2, the sensor sensitivity, the hysteresis error, and the variation in the sensor sensitivity were measured. The fixed base 65 holds the torque sensor while surrounding the outer peripheral side of the torque sensor. The aluminum fixing base covers the outer peripheral side of the torque sensor with aluminum, and the resin fixing base covers the outer peripheral side of the torque sensor with resin.

In this experiment, a torque sensor that uses a resin fixing base and does not have the coil shield portions 6 and 7 of the present embodiment is referred to as a "sensor fixing base (resin)", and this implementation is performed using an aluminum fixing base. A torque sensor provided with aluminum coil shield portions 6 and 7 similar to the embodiment is referred to as "sensor fixing base (Al) + side surface Al shield". Further, a torque sensor provided with a shield portion by a dust core using an aluminum fixing base is referred to as "sensor fixing base (Al) + side powder magnetic core shield", and the present embodiment uses a resin fixing base. The configuration that holds the torque sensor 1 is referred to as "resin fixing base + side shield".

For "resin fixing base + side shield", measure only when the torque applied to the rotation shaft 2 is ± 300 Nm, and measure "sensor fixing base (resin)" and "sensor fixing base (Al) + side Al shield". , And "Sensor fixing base (Al) + side dust core shield" were measured when the torque applied to the rotation shaft 2 was ± 50 Nm, ± 150 Nm, and ± 300 Nm.

As for the sensor sensitivity, as shown in FIG. 8, an output of approximately 5.6 mV / Nm was obtained regardless of the torque and torque sensor. That is, it can be seen that the presence or absence of the side shield portion has almost no effect on the sensor sensitivity.

As for the hysteresis error, as shown in FIG. 9, it was found that the error tends to increase as the torque increases. When the torque applied to the rotation shaft 2 is ± 300 Nm, the hysteresis error of the torque sensor 1 of the present embodiment "resin fixing base + side shield" is smaller than that of the "sensor fixing base (resin)". That is, it can be seen that the hysteresis error is reduced (effective) by the coil shield portions 6 and 7 covering the side surfaces of the detection coils 30 and 35. Further, when the torque applied to the rotation shaft 2 is ± 300 Nm, the hisiteris error of the "resin fixing base + side shield" which is the torque sensor 1 of the present embodiment is "sensor fixing base (Al) + side Al shield". Was equivalent to. From this, it can be seen that it is less necessary to provide a shield portion on the outer periphery of the magnetic ring 8.

As for the degree of variation in the sensor sensitivity, as shown in FIG. 10, the “resin fixing base + side shield” and the “sensor fixing base (Al) + side Al shield” provided with the coil shield portions 6 and 7 of the present embodiment have. , The variation was smaller than other configurations, and good results were obtained.

Next, the influence of the magnetic field generated when the torque motor was operated was measured using the measuring device 70 shown in FIG. The torque motor is an electric motor that rotationally drives the rotary shaft 2 and applies torque to the rotary shaft 2. A torque motor was placed at a distance of about 1 m from the torque sensor 1. As shown in FIG. 11, the measuring device 70 includes a torque meter 71, a connection unit 72, a drive detection circuit 73, an AD board 74, and a calculation unit 75.

The torque meter 71 is a sensor that measures the torque applied to the rotary shaft 2 from the torque motor. The connection portion 72 is a part of a path for sending a signal transmitted by the shielded wire 53 to the drive detection circuit 73. The connection portion 72 is configured by assembling, for example, a connector.

The drive detection circuit 73 detects the torque applied to the rotation shaft 2 based on the signal detected by the torque sensor 1, similarly to the measurement unit 41 described above. The AD board 74 has the function of a well-known analog-to-digital converter. The AD board 74 converts the analog signal from the torque meter 71 into a digital signal, and also converts the analog signal from the drive detection circuit 73 into a digital signal and sends it to the arithmetic unit 75.

The arithmetic unit 75 is configured as a well-known arithmetic unit such as a personal computer. The calculation unit 75 outputs the torque measured by the torque meter 71 and the torque measured by the torque sensor 1 in chronological order.

Using such a measuring device 70, the output from the torque sensor in a state where the power of the torque motor is turned on and the torque motor is not driven (a state in which torque is not applied from the torque motor to the rotary shaft 2) is examined. rice field. The power is turned on to the torque motor about 9 seconds after the start of measurement. From about 9 seconds after the start of measurement to about 30 seconds, the power of the torque motor is turned on and the torque motor is not driven. The state in which the power of the torque motor is turned on means a standby state in which the torque motor can be operated at any time, for example, a state in which only the exciting current is passed through the exciting torque motor.

In the torque sensor 1 of the present embodiment in this experiment, as shown in FIG. 12, the output from the torque sensor 1 did not fluctuate significantly before and after the power of the torque motor was turned on, and the output was stable at less than ± 20 mV. On the other hand, in the torque sensor of the comparative example not provided with the coil shield portions 6 and 7 of the present embodiment, as shown in FIG. 13, an output of about -80 mV was generated from the torque sensor 1 after the power of the torque motor was turned on. .. That is, in the torque sensor of the comparative example, due to the influence of the magnetic field generated by the torque motor, the same output as when the torque was applied was generated even though the torque was not applied to the rotating shaft 2.

From these results, the coil shield portions 6 and 7 covering the side surfaces of the detection coils 30 and 35 are effective in shielding the electromagnetic noise generated from the torque motor, and the shield portions are provided on the outer periphery of the detection coils 30 and 35. It can be seen that the need to provide is low.

[1-5. effect]
According to the embodiment described in detail above, the following effects are obtained.
(1a) One aspect of the present disclosure is a torque sensor 1 for measuring torque applied to a rotating shaft having magnetostrictive characteristics, which includes a plurality of detection coils 30, 35, a measuring unit 41, and a coil shield unit 6, 7 and a magnetic ring 8.

The plurality of detection coils 30 and 35 are configured by winding an insulated wire around the rotating shaft at a distance set in advance from the rotating shaft. The coil shield portions 6 and 7 are formed of a material that suppresses the transmission of electromagnetic waves, and cover at least a part of the side surface portions 30A and 30B which are the end faces of the plurality of detection coils 30 and 35 on the L side in the axial direction. The measuring unit 41 measures the torque applied to the rotating shaft by detecting the change in the inductance of the plurality of detection coils 30 and 35. The magnetic ring 8 is arranged on the outer peripheral side of the plurality of detection coils and has a magnetic material formed in a hollow cylindrical shape. On the outer peripheral side of the magnetic ring 8, a member having a material that allows the transmission of electromagnetic waves is arranged.

According to such a configuration, by covering the side surface portions 30A and 30B of the plurality of detection coils 30 and 35 with the shield portion, it is possible to reduce the influence of the detection coils 30 and 35 by the electromagnetic noise. Further, according to such a configuration, the outer peripheral side of the magnetic ring 8 is not covered with a member that blocks the transmission of electromagnetic waves, so that the hysteresis error of the torque sensor can be suppressed.

Further, according to such a configuration, since the magnetic ring 8 is provided, it is possible to suppress the magnetic flux generated in the detection coils 30 and 35 from leaking to the outside, and it is possible to suppress the deterioration of the sensor sensitivity.

(1b) In one aspect of the present disclosure, the coil shield portions 6 and 7 may be arranged in contact with the side surface portions 30A and 30B.
According to such a configuration, since the coil shield portions 6 and 7 are arranged in contact with the side surface portions 30A and 30B, it is possible to further suppress the invasion of electromagnetic noise into the detection coils 30 and 35.

(1c) In one aspect of the present disclosure, the coil shield portions 6 and 7 may cover the entire region where the insulated wire is arranged on the side surface portions 30A and 30B.
According to such a configuration, since the coil shield portions 6 and 7 cover the entire region where the insulated wires are arranged on the side surface portions 30A and 30B, electromagnetic noise is further suppressed from entering the detection coils 30 and 35. be able to.

(1d) One aspect of the present disclosure may further include a terminal portion 50 and a metal terminal shield portion 60. An electric wire electrically connected to the insulated electric wire is connected to the terminal portion 50. The terminal shield portion 60 covers the periphery of the terminal portion 50.

According to such a configuration, since the metal terminal shield portion 60 is provided, it is possible to suppress the intrusion of electromagnetic noise into the terminal portion 50.
[2. Other embodiments]
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and can be variously modified and implemented.

(2a) In the above embodiment, the coil shield portions 6 and 7 are arranged in contact with the side surface portions 30A and 30B, but the present invention is not limited thereto. For example, the coil shield portions 6 and 7 may be arranged apart from the side surface portions 30A and 30B by a predetermined distance.

(2b) In the above embodiment, the coil shield portions 6 and 7 are configured to cover the entire region where the insulated wire is arranged on the side surface portions 30A and 30B, but the present invention is not limited thereto. For example, the coil shield portions 6 and 7 may cover at least a part of the region where the insulated wire is arranged on the side surface portions 30A and 30B.

(2c) A plurality of functions possessed by one component in the above embodiment may be realized by a plurality of components, or one function possessed by one component may be realized by a plurality of components. .. Further, a plurality of functions possessed by the plurality of components may be realized by one component, or one function realized by the plurality of components may be realized by one component. Further, a part of the configuration of the above embodiment may be omitted. Further, at least a part of the configuration of the above embodiment may be added or replaced with the configuration of the other above embodiment. It should be noted that all aspects included in the technical idea specified from the wording described in the claims are embodiments of the present disclosure.

(2d) In addition to the torque sensor described above, the present disclosure can be realized in various forms such as a system provided with the torque sensor.

1 ... Torque sensor, 2 ... Rotating shaft, 5 ... Coil for magnetic strain type torque sensor, 6 ... Coil shield part, 7 ... Coil shield part, 8 ... Magnetic ring, 9 ... Terminal holding part, 20 ... Bobbin, 20A ... Arrangement surface , 30 ... 1st detection coil, 30A, 30B ... side surface part, 35 ... second detection coil, 41 ... measurement part, 50 ... terminal part, 52 ... insulated wire, 53 ... shield wire, 60 ... terminal shield part, 62 ... Resin member, 65 ... fixed base, 70 ... measuring device.

Claims (4)

A torque sensor for vehicles that measures the torque applied to a rotating shaft having magnetostrictive characteristics.
A plurality of detection coils configured by winding an insulated wire around the rotating shaft at a preset distance from the rotating shaft.
A coil shield portion formed of a material that suppresses the transmission of electromagnetic waves that covers at least a part of a side surface portion that is an axial end surface of the rotation axis in the plurality of detection coils.
A measuring unit that measures the torque applied to the rotating shaft by detecting a change in inductance in the plurality of detection coils, and a measuring unit.
A magnetic ring having a magnetic material arranged in a hollow cylindrical shape and arranged on the outer peripheral side of the plurality of detection coils,
A terminal portion to which an electric wire electrically connected to the insulated electric wire is connected,
A terminal shield portion made of a conductive material that covers the periphery of the terminal portion, and a terminal shield portion.
Equipped with
A torque sensor in which a member having a material that allows transmission of electromagnetic waves is arranged on the outer peripheral side of the magnetic ring. The vehicle torque sensor according to claim 1.
The coil shield portion is a torque sensor arranged in contact with the side surface portion. The vehicle torque sensor according to claim 1 or 2.
The coil shield portion is a torque sensor that covers the entire area where the insulated wire is arranged on the side surface portion. The vehicle torque sensor according to any one of claims 1 to 3 .
The member having a material that allows the transmission of electromagnetic waves is a torque sensor made of a non-metal material.

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