JP2010203960A - Torque detection device, and electric power steering device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect a torque having high reliability by three detection parts, and to connect a harness to each detection part through a connector of an 8-pin system which is used generally, in a control system of an electric power steering system. <P>SOLUTION: The torque detection device includes the harness 8 connected through first and second connectors 7, 9 to first to third terminals of the three detection parts 5a, 5b, 5c for detecting a magnetic change of a magnetic circuit forming member. Some terminal of at least one of the detection parts 5a, 5b, 5c is connected to some terminal of another detection part, and thereby the total number of each connection terminal at the first and second connectors 7, 9 is eight or less. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a torque detection device that detects torque applied to a rotating body, and an electric power steering device that includes a torque detection device and an electric motor for assisting steering.

  In an electric power steering device that assists steering by driving a steering assisting electric motor in response to a rotation operation of a steering member such as a steering wheel and transmitting the rotational force of the electric motor to a steering mechanism, It is necessary to detect the steering torque applied to the steering member to be used for drive control. For this detection, a torque detection device constructed in the middle of the steering shaft that connects the steering member and the steering mechanism is conventionally used. ing.

  This torque detection device divides a steering shaft to be detected into a first shaft and a second shaft that are coaxially connected by a small-diameter torsion bar as a torsion spring, and rotates the steering member. When a steering torque is applied to the steering shaft, a relative angular displacement is generated between the first shaft and the second shaft with the torsion bar being twisted, and the steering torque is detected using the relative angular displacement as a medium. It is as composition to do.

  The relative angular displacement of the first axis and the second axis has been conventionally detected by various means, one of which is a cylindrical magnet that rotates integrally with the first axis, and one that rotates integrally with the second axis. There is a torque detection device that uses a change in magnetic flux passing through a magnetic circuit with a magnetic yoke (see, for example, Patent Document 1).

  The magnetic yoke that rotates integrally with the second shaft is a ring made of a soft magnetic material formed by arranging a plurality of magnetic pole claws extending in the axial length direction on one side of an annular yoke body, and each magnetic pole. A pair of claws alternately arranged in the circumferential direction and arranged in the axial length direction is fixed to the second shaft as a set. The cylindrical magnet that rotates integrally with the first shaft is a multipolar magnet in which the same number of pairs of magnetic poles as the magnetic pole claws of the magnetic yoke are arranged in the circumferential direction, and is displaced relative to the first and second axes. In a neutral state in which no magnetic field is generated, the magnetic yoke is fixed to the first shaft in phase with the circumferential direction so that the magnetic pole claws of the magnetic yoke are aligned with the boundary between the N pole and the S pole.

  On the outside of the two magnetic yokes, a magnetism collecting ring made of a soft magnetic material is arranged so as to face and oppose each yoke body. Each of these magnetism collecting rings has a magnetism collecting portion that is connected to each other with a predetermined air gap therebetween, and a magnetic sensing element such as a Hall element is used in the air gap of these magnetism collecting portions. A detection unit is arranged.

  When a relative angular displacement occurs between the first axis and the second axis by the above configuration, a phase difference in the opposite direction occurs between the magnetic pole claws of the two magnetic yokes and the magnetic pole of the cylindrical magnet, The magnetic flux leaking to the air gap between the magnetic collecting portions of the respective magnetic collecting rings increases or decreases due to the change in density of the magnetic flux in each of the different magnetic yokes according to this phase difference, and the detection unit corresponding to this increase or decrease By taking out this output change, it is possible to detect the relative angular displacement between the first axis and the second axis, and to obtain the torque (steering torque) applied to the first axis and the second axis.

JP 2003-149062 A

  When the torque detection device configured as described above is applied to an electric power steering device, a fail countermeasure is indispensable for eliminating the unstable steering assistance due to erroneous detection of the steering torque. FIG. 8 is an explanatory diagram showing a configuration of an electric circuit of a detection unit in a conventional torque detection device. Conventionally, as disclosed in Patent Document 1, two detectors 100 and 100 having first to third terminals are arranged on the circumference of the magnetism collecting ring. Even when it is determined that one of the detection units 100 and 100 is in a fail state by sequentially performing the fail determination of each of the detection units 100 and 100 by comparing the output signals, the torque generated by the output of the other detection unit 100 Detection is possible, and steering assistance can be continued. Moreover, the harness connected to the two detection units 100 and 100 includes one plus-side power line 101 connected to the first terminal of each detection unit 100 and 100 and the second of each detection unit 100 and 100. And one signal line 103 and 103 connected to the third terminal of each of the detection units 100 and 100.

  However, in the conventional fail countermeasures as described above, a short circuit (a power supply fault or a ground fault) occurs in the positive side power supply line 101 or the negative side power supply line 102 of the two detection units 100 and 100, and the supply of power is prevented. In the case where the outputs of both the detection units 100 and 100 are lost at the same time because they are blocked, there is a problem that the steering assistance cannot be continued without any effect.

  Further, in such a case, the above-described fail determination based on the output comparison between the two detection units 100 and 100 is also uncertain, so that erroneous steering assistance based on the detection result of the incorrect steering torque may be executed. There is also.

  In order to solve such a problem, for example, three or more detection units are used, and even when the outputs of the two detection units fail, torque detection based on the outputs of the other detection units can be performed. It is conceivable to configure. In this case, the harness connected to the terminals of the three detectors each having the first to third terminals has three harnesses, each of which is a plus-side power line, a minus-side power line, and a signal line. Each of the plus side power line, the minus side power line and the signal line of the harness is connected to the connection terminal of the connector, and a connector having nine connection terminals, in other words, a 9-pin type connector is required.

  However, in order to increase the space efficiency of the connector, an 8-pin type connector having two rows of pins and having eight connection terminals is generally used in the control system in the electric power steering apparatus. As described above, when a 9-pin type connector is required, the control system needs to be changed, and it is not possible to cope with the change only by changing the torque detection device. In addition, when the pin arrangement is a two-row connector, it is necessary to use a 10-pin type connector, and one pin is not used, resulting in a reduction in space efficiency. In addition, the control system may be increased in size.

  The present invention has been made in view of such circumstances, and a main object thereof is to detect torque with high reliability by using three detection units, and furthermore, an 8-pin that is generally used in a control system for an electric power steering apparatus. An object of the present invention is to provide a torque detection device capable of connecting a harness to each detection unit with a connector of a type, and an electric power steering device including the torque detection device.

  A torque detection device according to a first aspect of the present invention includes a magnetic circuit forming member that rotates integrally with a rotating body to which torque is applied, each of which has first to third terminals, and a magnetic amount of the magnetic circuit forming member. Each of the detection units, a first connector connected to each of the terminals of each detection unit, and a harness connected to the first connector by a second connector. A torque detection device that detects torque applied to the rotating body based on a detection value detected by a unit, wherein at least one of the detection units is any terminal of another detection unit The total number of connection terminals in each of the first and second connectors is 8 or less.

  A torque detection device according to a second aspect of the present invention includes, in the first aspect, a branch line connected to the terminal of the other detection unit to which the terminal of the at least one detection unit is connected. The second connector has a second connection terminal corresponding to the branch line, and the harness has a power supply line connected to the second connection terminal.

  According to a third aspect of the present invention, there is provided an electric power steering apparatus for steering assistance based on torque detected by the torque detecting apparatus, wherein the steering shaft, the torque detecting apparatus described in the first or second invention, and the harness are connected. And a transmission means for transmitting the rotational force of the electric motor to a steering mechanism.

  According to the first and third inventions, since torque can be detected by the three detection units, torque detection based on the outputs of the other detection units even when the outputs of the two detection units are not accurate. This makes it possible to detect torque with high reliability. In addition, since the harness can be connected to each detection unit with an 8-pin connector that is commonly used as a control system in an electric power steering apparatus, it can be compatible with existing control systems and has high reliability. A torque detector can be provided at low cost. In addition, the space efficiency of the connector mounting is not sacrificed, and the control system is not increased in size.

  According to the second invention, the number of connection terminals connected to the first terminals of the three detection units and / or connection terminals connected to the second terminals of the three detection units can be reduced, and the harness Since two or more power supply lines can be secured, torque can be detected even when one of the power supply lines is disconnected, and highly reliable torque detection can be performed.

  According to the third aspect of the invention, the torque detection device and the control unit are arranged at a relatively separated location, the harness length is relatively long, and the harness can be easily damaged. Can do.

It is a disassembled perspective view which shows the structure of the torque detection apparatus which concerns on this invention. It is a longitudinal section showing the state where the torque detector concerning the present invention was built in the electric power steering device. It is explanatory drawing which shows the positional relationship of the circumferential direction of the magnetic pole nail | claw of a magnetic yoke, and the N pole and S pole of a cylindrical magnet. It is explanatory drawing which shows the structure of the electric circuit of the detection part in the torque detection apparatus which concerns on this invention. It is a flowchart which shows an example of a torque calculation procedure. It is explanatory drawing which shows the structure of the other electric circuit of the detection part in the torque detection apparatus which concerns on this invention. It is explanatory drawing which shows the structure of the other electric circuit of the detection part in the torque detection apparatus which concerns on this invention. It is explanatory drawing which shows the structure of the electric circuit of the detection part in the conventional torque detection apparatus.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.
Embodiment 1
FIG. 1 is an exploded perspective view showing a configuration of a torque detection device according to the present invention, and FIG. 2 is a longitudinal sectional view showing a state in which the torque detection device is incorporated in an electric power steering device.

  The torque detection device A according to the present invention detects a torque applied to the first shaft 11 and the second shaft 12 that are coaxially connected via the torsion bar 10, and is a cylindrical magnet that rotates integrally with the first shaft 11. 2 and a set of two magnetic yokes 3 and 3 that rotate integrally with the second shaft 12. The cylindrical magnet 2 and the magnetic yokes 3 and 3 constitute a magnetic circuit forming member.

  The torsion bar 10 is a small-diameter round bar that acts as a torsion spring, and the first shaft 11 and the second shaft 12 are connected with torsion holes 11a and 12a formed in the respective shaft centers. The large-diameter connecting portions provided at both ends of the bar 10 are fitted in and positioned in the circumferential direction as will be described later, and are then integrated and connected by driving the separate connecting pins 11b and 12b. . When a rotational torque is applied to the first shaft 11 and the second shaft 12 connected in this way, the torsion bar 10 is twisted and deformed by the action of the rotational torque, and the first shaft 11 and the second shaft 12 are deformed. In the meantime, a relative angular displacement corresponding to the magnitude of the rotational torque occurs in the direction of the rotational torque. The first shaft 11 and the second shaft 12 constitute a rotating body to which torque is applied.

  As shown in FIG. 1, the cylindrical magnet 2 that rotates integrally with the first shaft 11 has a plurality of N poles 21 and S poles 22 arranged on the circumference, and the end surfaces and inner surfaces thereof have an appropriate thickness. It is comprised as a multipolar magnet covered with the resin-made holding body 23, and is externally fixed by the 1st axis | shaft 11 via the holding body 23, as shown in FIG.

  As shown in FIG. 1, the magnetic yokes 3 and 3 that rotate integrally with the second shaft 12 are provided with a plurality of magnetic pole claws 32 extending in the axial direction on the inner surface of the annular yoke body 31 in the circumferential direction. This is a ring made of a soft magnetic material. The magnetic pole claw 32 has a triangular shape reduced toward the extended end, and the two magnetic yokes 3 and 3 face each other on the protruding side of the magnetic pole claw 32 and are alternately arranged in the circumferential direction. Are arranged on the same axis, and are integrally held by a resin holding cylinder 33 formed into a cylindrical shape.

  The magnetic yokes 3 and 3 configured as described above are fixed to the shaft end portion of the second shaft 12 by externally fitting an extension portion on one side of the holding cylinder 33, as shown in FIG. The magnetic pole claws 32 of the magnetic yokes 3 and 3 exposed inside the cylinder 33 are assembled so as to face the outer peripheral surface of the cylindrical magnet 2 fitted and fixed to the first shaft 11 with a slight air gap. Yes.

  FIG. 3 is an explanatory view showing a circumferential positional relationship between the magnetic pole claw 32 of the magnetic yoke 3 and the N pole 21 and the S pole 22 of the cylindrical magnet 2. FIG. 3B shows the positional relationship at the time of assembly. As shown in FIG. 3, the magnetic yokes 3 and 3 and the cylindrical magnet 2 have a magnetic pole claw 32 of the magnetic yokes 3 and 3 that is a cylindrical magnet. The phase is aligned in the circumferential direction so as to coincide with the boundary between the N pole 21 and the S pole 22 arranged on the circumference of 2. In this phase alignment, when the first shaft 11 and the second shaft 12 are connected by the torsion bar 10, the circumferential positions of the cylindrical magnet 2 and the magnetic yokes 3, 3 together with the first shaft 11 and the second shaft 12 are adjusted. It is realized by.

  In such an assembled state, the magnetic pole claws 32 of the two magnetic yokes 3 and 3 are in a magnetic field formed between the N pole 21 and the S pole 22 adjacent to each other on the circumference of the cylindrical magnet 2. The magnetic flux generated in the yoke body 31 that is located under the same conditions and communicates with the bases of the magnetic pole claws 32 is the same.

  When a relative angular displacement occurs due to torsion of the torsion bar 10 between the first shaft 11 to which the cylindrical magnet 2 is fixed and the second shaft 12 to which the magnetic yokes 3 and 3 are fixed, the respective magnetic yokes 3. , 3 and the phases of the N pole 21 and the S pole 22 of the cylindrical magnet 2 change in opposite directions as shown in FIG. 3 (a) or 3 (c). When this phase change occurs, the magnetic field claws 32 of one magnetic yoke 3 and the magnetic field claws 32 of the other magnetic yoke 3 have opposite magnetic field lines increasing, and the opposite magnetic fluxes are applied to the respective yoke bodies 31. Will occur. The direction of the magnetic flux generated at this time is determined according to the direction of the relative angular displacement generated between the cylindrical magnet 2 and the magnetic yokes 3, 3, that is, between the first shaft 11 and the second shaft 12. The density corresponds to the magnitude of the relative angular displacement.

  Two magnetism collecting rings 4 and 4 are disposed outside the magnetic yokes 3 and 3. These magnetism collecting rings 4 and 4 are annulus made of a soft magnetic material having an inner diameter slightly larger than the outer diameter of the yoke body 31, and as shown in FIG. The magnetic flux collecting projections (magnetic flux collecting portions) 41, 41 are provided that extend in the axial length direction and have their tip portions bent outward in the radial direction. The two magnetism collecting rings 4 and 4 are arranged coaxially with the extended sides of the magnetism collecting protrusions 41 and 41 facing each other, and the bent portions of the respective tips face each other with a predetermined air gap therebetween. As shown in FIG. 2, the resin is positioned and held integrally with a resin holding cylinder 42, and is fitted into the housing 13 partially shown in FIG. The inner peripheral surfaces of the magnetic yokes 3 and 3 are assembled so as to be close to and opposed to the outer peripheral surface of the yoke body 31 of each of the different magnetic yokes 3 and 3.

  Magnetic fluxes generated inside the yoke body 31 located inside each of the magnetic flux collecting rings 4 and 4 assembled in this way are induced. This magnetic flux is focused on the tip of each of the separate magnetic flux collecting protrusions 41 and 41 and leaks into the air gap between them.

  Between each of the three magnetic flux collecting protrusions 41, 41 of the magnetic flux collecting rings 4, 4, first to third detection portions 5a, 5b, 5c using magnetic detection elements such as Hall elements are respectively arranged. is there.

  FIG. 4 is an explanatory diagram showing the configuration of the electric circuit of the detection unit. The first to third detection units 5a, 5b, and 5c are connected to the first terminals 5aV, 5bV, and 5cV for the positive power supply line to which the connection lines 50aV, 50bV, and 50cV are connected, and the connection lines 50aG, 50bG, and The second terminals 5aG, 5bG, 5cG for the negative power supply line to which 50cG is connected and the third terminals 5aS, 5bS, 5cS for signal extraction to which the connection lines 50aS, 50bS, 50cS are connected The connection line 50bG connected to the second terminal 5bG in the second detection unit 5b is connected to the connection line 50cG connected to the second terminal 5cG in the third detection unit 5c. 6 and two connections of the first and third detection units 5a and 5c, each of the three connection lines 50aG, 50bG, 50cG and 50aS, 50bS, 50cS, and the second detection unit 5b. 50BV, and a 50bS is connected to the first connector 7.

  As shown in FIG. 2, the circuit board 6 is supported to the outside by a resin support leg 44 continuously provided on a part of the outer periphery of the holding cylinder 42, and each of the detection portions 5a, 5b, 5c is Each of the connection lines is positioned in an air gap secured between the separate magnetic flux collection protrusions 41 and 41, using the connection lines as support bodies. The detectors 5a, 5b, 5c arranged in this way emit output signals corresponding to the magnetic flux leaking into the respective air gaps.

  The output signals of the detectors 5a, 5b, and 5c are changed by the induced magnetic flux inside the yoke bodies 31 and 31 facing the magnetism collecting rings 4 and 4, and these induced magnetic fluxes are respectively applied to the cylindrical magnet 2 as described above. Since it corresponds to the relative angular displacement, that is, the relative angular displacement between the first axis 11 and the second axis 12, it is added to the first axis 11 and the second axis 12 of the detection units 5a, 5b, 5c, and the relative It corresponds to the direction and magnitude of the rotational torque that causes the angular displacement, and the rotational torque applied to the first shaft 11 and the second shaft 12 can be detected based on the output change of the detectors 5a, 5b, 5c. .

  As shown in FIGS. 2 and 4, the circuit board 6 is connected to the first terminals 5aV, 5bV, and 5cV of the first to third detectors 5a, 5b, and 5c via connection lines 50aV, 50bV, and 50cV. Three connection terminals 7aV, 7bV, 7cV, and two connection terminals 7aG connected to the second terminals 5aG, 5cG of the first and third detectors 5a, 5c via connection lines 50aG, 50cG, respectively. 7cG and three connection terminals 7aS, 7bS, and 7cS connected to the third terminals 5aS, 5bS, and 5cS of the first to third detection units 5a to 5c through connection lines 50aS, 50bS, and 50cS, respectively. An 8-pin first connector 7 is provided.

  To the first connector 7, a harness 8 for connecting each of the detection units 5 a, 5 b, 5 c to an external device is connected by a common second connector 9.

  As described above, the detection units 5a, 5b, and 5c using Hall elements require a plus-side power line, a minus-side power line, and a signal extraction signal line.

  The harness 8 has eight connection lines including plus-side power supply lines 8aV, 8bV, and 8cV, minus-side power supply lines 8aG and 8cG, and signal extraction signal lines 8aS, 8bS, and 8cS.

  At one end of the harness 8, there are three connection terminals 9aV, 9bV, 9cV connected to the plus side power supply lines 8aV, 8bV, 8cV, and two connection terminals 9aG, 9cG connected to the minus side power supply lines 8aG, 8cG. A second connector 9 of an 8-pin type having three connection terminals 9aS, 9bS, 9cS connected to the signal lines 8aS, 8bS, 8cS is provided. A third connector (not shown) for connecting to an external device is connected to the other end of each harness 8.

  As described above, the harness 8 connected to the three detection units 5a, 5b, and 5c includes the three plus-side power supply lines 8aV, 8bV, and 8cV, the two minus-side power supply lines 8aG and 8cG, and the three The first and second connectors 7 and 9 for connecting the harness 8 to each of the detectors 5a to 5c are connected to the plus-side power line 8aV. The signal lines 8aS, 8bS, and 8cS have a total of eight connection lines. , 8bV, 8cV, three connection terminals connected to the negative power supply lines 8aG, 8cG, and three connection terminals connected to the signal lines 8aS, 8bS, 8cS. Even if there is no normal output from the first detection unit 5a or the second and third detection units 5b and 5c due to, for example, disconnection of one negative power supply line 8aG or 8cG, etc. Detection unit (5b, 5 Alternatively, torque detection based on the output of 5a) can be performed, highly reliable torque detection can be performed, and an existing control system in an electric power steering apparatus can be supported, and a highly reliable torque detection apparatus can be made inexpensively. Can be provided. In addition, the space efficiency of the connector mounting is not sacrificed, and the control system is not increased in size.

  The outputs of the first to third detection units 5a, 5b, and 5c are given to a torque calculation unit (not shown) via the harness 8, and the torque calculation unit calculates torque. FIG. 5 is a flowchart showing an example of a torque calculation procedure.

The torque calculation unit takes in the outputs (voltage values) T ₁ , T ₂ , T ₃ of the detection units 5a, 5b, 5c at a predetermined sampling period (step S1), and calculates the deviation ΔT (step S2). ), It is determined whether or not the deviation ΔT exceeds a predetermined upper limit value Tmax (step S3).

When it is determined that the deviation ΔT is equal to or less than the upper limit value Tmax (step S3: NO), the torque calculation unit has all the outputs T ₁ , T ₂ , T ₃ of the _three detection units 5a, 5b, 5c. It recognizes that it is normal, calculates torque using these outputs T ₁ , T ₂ , T ₃ (step S 4), returns to step S ₁ and takes in new outputs T ₁ , T ₂ , T _3. Repeat the operation. The calculation of the torque in step S4 is performed by applying any one or all of the outputs T ₁ , T ₂ , T ₃ of the detectors 5a, 5b, 5c to a predetermined arithmetic expression or map. be able to.

  When it is determined in step S3 that the deviation ΔT has exceeded the upper limit value Tmax (step S3: YES), the torque calculation unit determines whether any of the three detection units 5a, 5b, and 5c is abnormal, Next, it is determined whether or not the abnormality is confirmed (step S5). This determination can be performed, for example, by counting the number of times of abnormality determination in step 3 and determining whether or not this count value exceeds a predetermined upper limit value.

When it is determined in step S5 that the abnormality is not confirmed (step S5: NO), the torque calculation unit or the outputs T ₁ and T ₂ of the previous sample values or the detection units 5a, 5b, and 5c before the abnormality determination is performed. , T ₃ (step S6), and when it is determined that the abnormality is confirmed (step S5: YES), one of the normal outputs T ₁ , T ₂ , T ₃ is used. The torque is calculated (step S7), and in either case, the process returns to step S1, and new outputs T ₁ , T ₂ , T ₃ are taken in and the above-described operation is repeated.

Note that the result of the abnormality confirmation is maintained once it has been established, and torque calculation using any of the normal outputs T ₁ , T ₂ , T ₃ is continued after the confirmation. After the abnormality is determined, the obtained torque calculation value is used as a torque value under the abnormal condition. For example, when the vehicle is used for detection of steering torque in the electric power steering device, the vehicle is safely used. Used for emergency steering control (life extension control) for the purpose of moving to a position. In this case, it is desirable to notify the driver of the occurrence of abnormality by notifying means such as generation of an alarm and appropriate display.

On the other hand, if the abnormality is not determined in step S5, the process proceeds to step S4 when the normality is determined in step S3. Therefore, any one of the outputs T ₁ , T ₂ , T ₃ of the detectors 5a, 5b, 5c is changed. It is possible to return to the normal torque calculation operation used. Thereby, it is possible to cope with temporary output fluctuations of the detection units 5a, 5b, and 5c caused by disconnection of connection lines in the harness. Therefore, there is no possibility that the outputs T ₁ , T ₂ , and T _{3 of} the detectors 5a, 5b, and 5c are not accurate at the same time, and when applied to the electric power steering apparatus, the above-described life extension control is surely performed. be able to.

  The torque detection device A configured as described above is used, for example, in an electric power steering device for a vehicle as shown in FIG. This electric power steering apparatus has a first shaft 11 as a steering shaft whose upper end is connected to a steering member, a second shaft 12 as a transmission shaft coaxially connected to the first shaft 11 by a torsion bar 10, A housing 13 surrounding the first shaft 11 and the second shaft 12 and rotatably supporting the first shaft 11 and the second shaft 12 by bearings; a steering assisting electric motor 14 attached to the housing 13; A speed reduction mechanism that transmits the rotational force of the drive shaft of the electric motor 14 to the second shaft 12, a torque detection device A, and a microprocessor connected to the harness 8 of the torque detection device A and the drive circuit of the electric motor 14. And a control unit 15 to be used. The control unit 15 includes the torque calculation unit. The speed reduction mechanism and the second shaft 12 constitute transmission means for transmitting the rotational force of the electric motor 14 to the steering mechanism.

Embodiment 2
FIG. 6 is an explanatory diagram showing a configuration of another electric circuit of the detection unit in the torque detection device. This torque detection apparatus A uses connection lines 50aG and 50bG connected to second terminals 5aG and 5bG in the first and second detection units 5a and 5b as second terminals 5cG in the third detection unit 5c. The connection line 50cG is connected to the connection line 50cG in the circuit board 6, and the branch line 5dG is connected to the connection line 50cG in the circuit board 6, and the first and second connectors 7 and 9 are connected to the connection line 50cG. It is what.

  The first connector 7 has a total of eight connection terminals 7aV, 7bV, 7cV, connection terminals 7aS, 7bS, 7cS, a connection terminal 7cG, and a second connection terminal 7dG connected to the branch line 5dG. .

  The harness 8 includes eight wires including plus-side power supply lines 8aV, 8bV, and 8cV, signal lines 8aS, 8bS, and 8cS, a minus-side power supply line 8cG, and a minus-side power supply line 8dG connected to the branch line 5dG.

The second connector 9 includes three connection terminals 9aV, 9bV, 9cV connected to the plus side power supply lines 8aV, 8bV, 8cV, and three connection terminals 9aS, 9bS, connected to the signal lines 8aS, 8bS, 8cS. 9 cS and two connection terminals 9 cG and 9 dG connected to the negative power supply lines 8 cG and 8 dG. 9dG constitutes the second connection terminal.
Since other configurations and operations are the same as those of the first embodiment, the same components are denoted by the same reference numerals, and detailed description thereof and description of operations and effects are omitted.

  In this embodiment, the harness 8 connected to the three detectors 5a, 5b, 5c has three plus power supply lines 8aV, 8bV, 8cV and two minus power supply lines 8cG, 8dG. And the three signal lines 8aS, 8bS, and 8cS, and the first and second connectors 7 and 9 that connect the harness 8 to the detection units 5a to 5c are plus Three connection terminals connected to the side power supply lines 8aV, 8bV, 8cV, two connection terminals connected to the negative side power supply lines 8cG, 8dG, and three connection terminals connected to the signal lines 8aS, 8bS, 8cS For example, even when one negative power supply line 8cG or 8dG is disconnected, torque detection based on the outputs of the detection units 5a, 5b, and 5c is possible, and highly reliable torque detection is possible. But Can, moreover, it is possible for an existing control system in the electric power steering apparatus, it is possible to provide an inexpensive high torque detector reliability.

Embodiment 3
FIG. 7 is an explanatory diagram showing the configuration of another electric circuit of the detection unit in the torque detection device. This torque detection device A uses connection lines 50bV and 50cV connected to first terminals 5bV and 5cV in the second and third detection units 5b and 5c as first terminals 5aV in the first detection unit 5a. The connection lines 50aG and 50bG connected to the second terminals 5aG and 5bG in the first and second detection units 5a and 5b are connected to the connection line 50aV connected to Connected to the connection line 50cG connected to the second terminal 5cG in the detection unit 5c in the circuit board 6, and further connected to the connection line 50aV and the second terminal 5cG connected to the first terminal 5aV. The branch lines 50dV and 50dG are connected to the connected connection line 50cG in the circuit board 6 respectively, and the first and second connectors 7 and 9 are in a 7-pin type.

  The first connector 7 includes a connection terminal 7aV, connection terminals 7aS, 7bS, and 7cS, a connection terminal 7cG, a second connection terminal 7dV connected to the branch line 5dV, and a second terminal connected to the branch line 5dG. And a total of seven connection terminals 7dG.

  The harness 8 includes a plus power line 8aV, signal lines 8aS, 8bS, and 8cS, a minus power line 8cG, a plus power line 8dV connected to the branch line 5dV, and a minus side connected to the branch line 5dG. There are seven power lines 8dG.

  The second connector 9 includes two connection terminals 9aV and 9dV connected to the positive power supply lines 8aV and 8dV, three connection terminals 9aS, 9bS and 9cS connected to the signal lines 8aS, 8bS and 8cS, and a minus There are a total of seven of the two connection terminals 9cG and 9dG connected to the side power supply lines 8cG and 8dG. Note that 9dV and 9dG constitute the second connection terminal.

In this embodiment, the harness 8 connected to the three detection units 5a, 5b, and 5c includes two plus-side power supply lines 8aV and 8dV, two minus-side power supply lines 8cG and 8dG, The first and second connectors 7 and 9 for connecting the harness 8 to each of the detectors 5a to 5c have a total of seven lines including three signal lines 8aS, 8bS, and 8cS. 7 having two connection terminals connected to the lines 8aV and 8dV, two connection terminals connected to the negative power supply lines 8cG and 8dG, and three connection terminals connected to the signal lines 8aS, 8bS and 8cS Because of the pin format, for example, when one positive power supply line 8aV or 8dV is disconnected or when one negative power supply line 8cG or 8dG is disconnected, it is based on the output of the detectors 5a, 5b, 5c. Torque detection Becomes possible, it is high torque detection reliability, moreover, it is possible for an existing control system in the electric power steering apparatus, it is possible to provide an inexpensive high torque detector reliability.
Since other configurations and operations are the same as those of the first embodiment, the same components are denoted by the same reference numerals, and detailed description thereof and description of operations and effects are omitted.

  In the embodiment described above, the cylindrical magnet 2 and the magnetic yokes 3 and 3 constitute a magnetic circuit forming member, but the N pole 21 and the S pole 22 are the first instead of the cylindrical magnet 2. The structure may be fixed to the outer peripheral portion of the shaft 11, and a magnetic circuit is formed by rotating integrally with the first shaft 11 and the second shaft 12 constituting the rotating body, and in other words, configured so that magnetic flux passes. Any magnetic circuit forming member configured to change magnetically may be used, and the configuration of the magnetic circuit forming member is not particularly limited.

  In the embodiment described above, the configuration includes three detection units 5a, 5b, and 5c. However, the configuration may include four or more detection units, and the number of detection units is not particularly limited.

  Further, the harness 8 according to the embodiment described above is configured such that each of the plus-side power supply line, the minus-side power supply line, and the signal line is combined into one and covered with insulation, but in addition, each detection unit 5a, The positive side power supply line, the negative side power supply line, and the signal line connected to 5b and 5c may be combined into three and each may be configured to be covered with insulation.

  Further, the torque detection device A according to the present invention may be used for devices other than the electric power steering device in addition to the electric power steering device.

A Torque detection device 11 First shaft (rotary body, steering shaft)
12 Second shaft (rotary body, transmission means)
2 Cylindrical magnet (magnetic circuit forming member)
3 Magnetic yoke (magnetic circuit forming member)
5a, 5b, 5c Detector 5aV, 5bV, 5cV First terminal 5aG, 5bG, 5cG Second terminal 5aS, 5bS, 5cS Third terminal 50aV, 50bV, 50cV Connection line 50aG, 50bG, 50cG Connection line 50aS, 50bS, 50cS Connection line 7 First connector 8 Harness 9 Second connector 8aV, 8bV, 8cV, 8dV Positive side power supply line 8aG, 8cG, 8dG Negative side power supply line 8aS, 8bS, 8cS Signal line 5dV, 5dG Branch line 14 Electric motor 15 control unit

Claims (3)

  A magnetic circuit forming member that rotates integrally with a rotating body to which torque is applied, each of which has first to third terminals, and three detection units that detect the magnetic amount of the magnetic circuit forming member; A first connector connected to each of the terminals of the detection unit; and a harness connected to the first connector by a second connector, and based on the detection values detected by the detection units. A torque detection device that detects torque applied to a rotating body, wherein at least one of the detection units is connected to one of terminals of another detection unit, and the first and second The total number of connection terminals in each of the connectors is 8 or less.   A branch line connected to the terminal of the other detection unit to which a terminal of the at least one detection unit is connected; and the first and second connectors are second connections corresponding to the branch line. The torque detecting device according to claim 1, further comprising: a terminal, wherein the harness includes a power line connected to the second connection terminal.   A steering shaft, the torque detection device according to claim 1, the harness is connected, and a controller that drives an electric motor for assisting steering based on the torque detected by the torque detection device, the electric motor An electric power steering apparatus comprising: a transmission means for transmitting the rotational force of the motor to the steering mechanism.

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