Patent Description:
Conventionally, a detection device that detects a magnetic flux generated in response to a movement of a movable body is known. In a power steering device of a vehicle, for example, a torque sensor disclosed in Patent Document <NUM> uses a magnetic sensor to detect changes in magnetic flux generated by a torsional displacement of a torsion bar housed in a housing, and detects a steering torque. This torque sensor has a cylinder portion having a spigot structure that is joined to a mounting hole of a housing in a sensor holder. A seal member is compressed and interposed between the mounting hole of the housing and an outer peripheral surface of the cylinder portion with the spigot structure to seal between the two. Then, an elastic force of the seal member acts on the cylinder portion with the spigot structure in a radial direction of the outer peripheral surface of the cylinder portion.

Further, conventionally, a detection device has a configuration in which a magnetic detection module including a magnetic sensor is inserted into a mounting hole of a housing. For example, in a torque detection device disclosed in Patent Document <NUM>, a case (that is, a magnetic detection module) including a detection unit, a detection circuit board, and the like is inserted into a through hole (that is, a mounting hole) from a radial direction of the housing. An outer end of the through hole in the housing and an outer surface of the case have positioning surfaces that determine the position of the detection unit in the housing.

Document <CIT> describes a magnetic detection module that is provided so as to be selectively mountable in any of housings having a plurality of specifications having different shapes or sizes of mounting portions, and detects magnetic flux generated in the housing, comprising: one or more magnetic sensors configured to detect magnetic flux; and a case in which the magnetic sensor is housed; wherein the magnetic detection module is configured to be attachable to the housing of a first specification without a cap being attached to the case.

Document <CIT> describes a magnetic rotational speed sensor comprising: a detection block with circuit components disposed on a holder; a cap for protecting the block; and a connector block having a flange on which a space for installing said detection block and said cap is provided, as well as connector terminals in the other end thereon separated by said flange. The detection block attached on said installing space being electrically coupled with said connector terminals.

Document <CIT> describes A detection device, comprising: a housing including a mounting hole provided inside with a set of yokes that transmit the magnetic flux generated according to a magnitude of a physical quantity to be detected; and a magnetic detection module mounted in the mounting hole in the housing and configured to detect the magnetic flux transmitted from the yoke by one or more magnetic sensors housed in a case, wherein the set of yokes has ring portions that face each other and form a magnetic circuit, the mounting hole of the housing has a hole formed on an opening side, wherein the magnetic detection module faces an inner wall of the mounting hole and includes a cylindrical portion (<NUM>, <NUM>) having a shaft portion inserted into the hole, and a sensor unit in which the magnetic sensor is housed and protrudes from the tip end surface of the cylindrical portion and is inserted between the ring portions of the set of yokes, in a direction orthogonal to an axial direction of the mounting hole and the cylinder portion, when a minimum distance between the sensor unit and the ring portion is defined as a sensor margin (µ), the one-sided fitting gap between the hole and the shaft portion is set to be smaller than the sensor margin.

Document <CIT> describes a torque detection device for automobile power-assisted steering, which has a torsion rod connecting an input shaft to an output shaft. A set of permanent magnets integrate the input shaft, and a pair of magnetic yokes integrates the output shaft. A flux collector support with slip rings is molded from plastic material. The support is mounted in a case of a steering system. A magnetic flux sensor is mounted on the support.

Document <CIT> describes a power steering device including: a housing which rotatably supports an input shaft and a handle side pinion shaft (output shaft), and is divided into a first housing and a second housing, and is fixed by using a housing fixing bolt; and a torque detection part in which a part of a relative angle detection part is connected to the input shaft and the handle side pinion shaft, and the first housing and the second housing are fixed by using the housing fixing bolt, and after that, a sensor structure is held by the housing and a relative rotational angle is measured between the input shaft and the handle side pinion shaft (output shaft).

Document <CIT> describes a method of manufacturing a torque sensor, which comprises a first and a second slip ring for collecting magnetic flux, said slip rings being housed in a sensor housing and separated from each other by an air gap.

The matter for which protection is sought is defined by the appended claims.

Generally, as a structure of a detection device that detects magnetic flux generated in response to movement of a movable body, a magnetic detection module having a magnetic sensor and outputting a detection signal to the outside is attached to a housing in which a movable body and a magnetic flux generating portion are housed. The magnetic detection module includes a case assembly in which the magnetic sensor is housed in the case. The case assembly includes a substrate on which a signal output circuit is mounted, a connector to which a signal line is wired, and the like in addition to the magnetic sensor. With such a module structure, in an actual product, the magnetic detection module supplied as a component from another place is attached to the housing at an assembly factory.

By the way, the torque sensor disclosed in Patent Document <NUM> includes a seal member, but in reality, depending on the part of the vehicle on which the torque sensor is mounted, the rack-mounted type is required to have a waterproof function, and the column-mounted type is not required to have a waterproof function. Therefore, when applied to a waterproof detection device, it is necessary to provide a sealing member between the magnetic detection module and the housing. When applied to non-waterproof detection device, it is not necessary to provide a sealing member between the magnetic detection module and the housing.

If a case dedicated to each of the waterproof and non-waterproof housings is manufactured by, for example, resin molding, two types of molds are required, and production adjustment and inventory management man-hours for the two types of cases are required. Further, for example, when there are a plurality of specifications having different shapes and sizes of sealing members among the waterproof specifications, it is necessary to switch the production of other models, and the mold cost and the management cost are increased.

In the configuration of Patent Document <NUM>, an inner wall of the mounting hole of the housing has a rectangular tubular shape. On the other hand, Patent Document <NUM> does not specifically specify the positioning configuration when the inner wall of the mounting hole of the housing has a cylindrical shape.

Further, in the configuration of Patent Document <NUM>, since an outer peripheral of the insertion portion is surrounded by a magnetic ring, there is no risk that the housing portion of the magnetic sensor will come into direct contact with the housing during the insertion work and be damaged. On the other hand, in a configuration in which the sensor unit in which the magnetic sensor is housed protrudes from a tip surface of the magnetic detection module, if the sensor unit interferes with a member on the housing side due to misalignment or tilt during insertion, the magnetic sensor may be damaged or its characteristics may change.

It is an object of the invention to provide a magnetic detection module that can be selectively attached to a plurality of housings having different specifications by a simple configuration change using a common component, a case assembly constituting the magnetic detection module, and its production method. The dependent claims are directed to preferred embodiments of the invention.

The magnetic detection module of the present invention is provided so as to be selectively mountable in any of housings having a plurality of specifications having different shapes or sizes of mounting portions, and detects magnetic flux generated in the housing. The magnetic detection module includes one or more magnetic sensors that detect magnetic flux, a case in which the magnetic sensors are housed, and a cap that can be attached to an end of the case and is provided with a sealing member.

This magnetic detection module can be attached to the housing of the first specification with the cap not attached to the case, and can be attached to the housing of the second specification through the sealing member with the cap attached to the case. The sealing member is not provided at the time when the cap is attached to the case, and may be provided before the cap is attached to the housing.

For example, this magnetic detection module further includes one or more magnetic flux guiding members in the case that guide the detected magnetic flux to the magnetic sensor.

In the present invention, the mounting specifications for the housing can be changed depending on the presence or absence of the cap. Specifically, for the waterproof housing, a magnetic detection module in which a cap provided with a sealing member is attached to the case is supplied. Further, for the non-waterproof housing, the case assembly without the cap is independently supplied as a magnetic detection module. Therefore, for example, when the case is manufactured by resin molding, only one type of mold is required for the case, and inventory management is simplified.

In addition, a case assembly that constitutes the above magnetic detection module is provided. The case assembly includes one or more magnetic sensors that detect magnetic flux and a case that houses the magnetic sensor. This case assembly can be independently attached to the housing of the first specification, and can be attached to the housing of the second specification through the sealing member with the cap provided with the sealing member attached to the end of the case.

Further, a production method for the above-mentioned magnetic detection module is provided. The production method of this magnetic detection module includes a storage process, a selection process, and a mounting process. In the storage process, one or more magnetic sensors that detect magnetic flux are housed in a case, and a case assembly is manufactured. In the selection process, according to the specifications of the housing to be attached, it is selected whether to use the case assembly alone or to attach a cap set for each housing specification to the end of the case. In the mounting process, when it is selected to mount the cap on the case in the selection step, the cap is mounted and fixed to the case.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:.

Hereinafter, a plurality of embodiments of a detection device and a magnetic detection module will be described with reference to the drawings. In the following embodiments, substantially same structural parts are designated with the same reference numerals thereby to simplify the description. The detection device of the present embodiment functions as a torque detection device that detects steering torque in an electric power steering device. Further, the magnetic detection module of the present embodiment is applied to the torque detection device. The first and second embodiments correspond to "disclosure of a first group". The third and fourth embodiments also correspond to "disclosure of a second group". In particular, a configuration in which an O-ring, which is a sealing member, is attached in the third embodiment also corresponds to "disclosure of the first group".

First, with reference to <FIG>, a basic configuration of the torque detection device <NUM> as "detection device" will be described. The torque detection device <NUM> includes a magnetic detection module <NUM> and detects torque based on magnetic flux generated according to the input torque.

The torque detection device <NUM> includes an element housed in a housing <NUM> mounted on a vehicle and an element configured as a magnetic detection module <NUM> and attached to the housing <NUM>. The element housed in the housing <NUM> includes a torsion bar <NUM>, a multipolar magnet <NUM>, a set of yokes <NUM>, <NUM>, and the like. The element configured as the magnetic detection module <NUM> include magnetic flux guiding members <NUM>, <NUM>, magnetic sensors <NUM>, <NUM> and the like.

One end portion of the torsion bar <NUM> is fixed to an input shaft <NUM> with a pin <NUM>, and another end portion of the torsion bar <NUM> is fixed to an output shaft <NUM> with a pin <NUM> so that the input shaft <NUM> and the output shaft <NUM> are connected on a same axis as a central axis O. The torsion bar <NUM> is an elastic member having a rod shape for converting a steering torque applied to a steering shaft <NUM> to a torsional displacement. In the multipolar magnet <NUM>, which is secured to the input shaft <NUM>, the N-poles and S-poles are disposed alternately in a circumferential direction.

The set of yokes <NUM> and <NUM> is made of a soft magnetic material and is fixed to the output shaft <NUM> on an outer diameter of the multipolar magnet <NUM>. Each yoke <NUM>, <NUM> has a ring portion <NUM>, <NUM> facing each other via a gap in an axial direction, and a plurality of claws <NUM>, <NUM> extending axially from an inner peripheral edge of each ring portion <NUM>, <NUM> toward the other ring portion. The same number of claws <NUM> and <NUM> as the north and south poles of the multipolar magnet <NUM> are provided at equal intervals on the entire circumference along the inner peripheral edge of the ring portions <NUM> and <NUM>. The claws <NUM> of the yoke <NUM> and the claws <NUM> of the yoke <NUM> are shifted in the circumferential direction, placed alternately. The pair of yokes <NUM> and <NUM> thus forms a magnetic circuit in a magnetic field generated by the multipolar magnet <NUM>.

The central axis O may be defined using any of the torsion bar <NUM>, the multipolar magnet <NUM>, and the yokes <NUM> and <NUM> as the reference, since they are all placed concentrically. In the present specification, it is basically described as "the central axis O of the yokes <NUM> and <NUM>" with reference to the yokes <NUM> and <NUM> in which the facing relationship with the magnetic flux guiding members <NUM> and <NUM> is focused. In the description of the embodiments, an axial direction and a radial direction of the torsion bar <NUM>, the multipolar magnet <NUM>, the yokes <NUM> and <NUM>, and the like are simply referred to as the "axial direction" and the "radial direction.

The magnetic flux guiding members <NUM> and <NUM> of the magnetic detection module <NUM> are made from a soft magnetic member, and a set of yokes <NUM> and <NUM> and a main body <NUM> face each other in the axial direction to guide the magnetic flux of the magnetic circuit to the magnetic sensors <NUM> and <NUM>. In the present embodiment, a set of magnetic flux guiding members <NUM> and <NUM> facing each other in the axial direction are provided.

Hereinafter, for convenience of explanation, the yoke <NUM> and the magnetic flux guiding member <NUM> arranged on the first shaft <NUM> side in <FIG> are referred to as "upper yoke <NUM>" and "upper magnetic flux guiding member <NUM>". Further, the yoke <NUM> and the magnetic flux guiding member <NUM> arranged on the second shaft <NUM> side are referred to as "lower yoke <NUM>" and "lower magnetic flux guiding member <NUM>". The upper magnetic flux guiding member <NUM> faces the upper yoke <NUM>, and the lower magnetic flux guiding member <NUM> faces the lower yoke <NUM>.

The set of magnetic flux guiding members <NUM> and <NUM> of the present embodiment has two extensions <NUM> and <NUM> branched from the main body <NUM>. Specifically, the extensions <NUM> and <NUM> extend from the main body <NUM> toward the outside of the yokes <NUM> and <NUM> in the radial direction. The magnetic sensor <NUM> is disposed between the extensions <NUM>, and the magnetic sensor <NUM> is disposed between the extensions <NUM>. The extensions <NUM> each have a step in the axial direction so as to have a minimum gap therebetween in a location where the magnetic sensor <NUM> is placed. The extensions <NUM> each have a step in the axial direction so as to have a minimum gap therebetween in a location where the magnetic sensor <NUM> is placed.

The magnetic sensors <NUM> and <NUM> detect the magnetic flux induced by the magnetic flux guiding members <NUM> and <NUM> from the ring portions <NUM> and <NUM> of the set of yokes <NUM> and <NUM>, convert it into a voltage signal, and output an external processing unit via a harness. Each of the magnetic sensors <NUM> and <NUM> is, for example, an IC package having a substantially rectangular parallelepiped shape, made using a Hall element, magnetoresistive element, or the like molded in resin. The magnetic detection module <NUM> of the present embodiment includes two magnetic sensors <NUM> and <NUM>, and redundantly outputs two values as steering torque to the processing unit. With such a redundant configuration, the processing unit can continue to control even if one of the information becomes unusable due to a failure of the magnetic sensor or the arithmetic circuit.

Here, with reference to <FIG>, a schematic configuration of an electric power steering device to which the torque detection device is applied will be described. While the electric power steering system <NUM> illustrated in <FIG> is of a column assist type, the torque detection device can be also used in rack assist electric power steering systems.

The torque detection device <NUM> for detecting steering torque is installed on a steering shaft <NUM> connected to a steering wheel <NUM>. A pinion gear <NUM> is provided at a tip of the steering shaft <NUM>, and a pinion gear <NUM> meshes with a rack shaft <NUM>. A pair of wheels <NUM> are rotatably connected to both ends of the rack shaft <NUM> via a tie rod or the like. A rotational movement of the steering shaft <NUM> is converted into linear movement of the rack shaft <NUM> by the pinion gear <NUM>, and the pair of road wheels <NUM> is steered.

The torque detection device <NUM> is provided between the input shaft <NUM> and the output shaft <NUM> constituting the steering shaft <NUM>, detects the steering torque applied to the steering shaft <NUM>, and outputs the torque to an ECU <NUM>. The ECU <NUM> controls an output of a motor <NUM> in accordance with the detected steering torque. The motor <NUM> generates a steering assist torque that is reduced by a reduction gear <NUM> and transmitted to the steering shaft <NUM>.

Next, a structure for attaching the magnetic detection module <NUM> to the housing <NUM> will be described. In the present embodiment, it is assumed that the housing <NUM> has two specifications in which the shape or size of the mounting portion is different. The housing <NUM> shown in <FIG> is a column-mounted type housing provided on the steering shaft of the electric power steering device. The housing <NUM> shown in <FIG> is a rack-mounted type housing provided on the rack shaft connecting the pinion gear at the tip of the steering shaft and the wheel.

The rack-mounted type housing <NUM> is in an environment where rainwater or the like is splashed from the road surface when the vehicle is traveling or the like. Therefore, in order to prevent water from entering the inside of the housing through the gap of the mounting portion, it is necessary to provide a sealing member on the mounting portion. On the other hand, in the column-mounted type housing <NUM> provided in the vehicle interior, there is no risk of water entering, so it is not necessary to provide a sealing member on the mounting portion.

That is, there are the non-waterproof housing <NUM> and the waterproof housing <NUM> depending on the mounting portion of the torque detection device <NUM> in the vehicle. The housing <NUM> corresponds to the "housing of the first specification", and the housing <NUM> corresponds to the "housing of the second specification". In addition, in this specification, "water" in "waterproof" means not only pure water but all liquids which may infiltrate the housing.

Both the housings <NUM> and <NUM> have a substantially cylindrical shape with the axis O as the central axis, and have a flat mounting plate <NUM> formed on a part of the outer periphery thereof. In the description of the housings <NUM> and <NUM>, the upper side in <FIG> and <FIG> is referred to as "upper" and the lower side is referred to as "lower" for convenience. The mounting plate <NUM> has mounting holes <NUM> and <NUM> formed across a plane including the central axis O, and fixing holes <NUM> such as bolts are formed on both sides of the mounting holes <NUM> and <NUM> in the circumferential direction. The alternate long and short dash line indicates a portion where a flange <NUM> shown in <FIG> and <FIG> abuts, and a fixing hole <NUM> corresponds to a position of a fixing hole <NUM> of the flange <NUM>.

As shown in <FIG>, in the column-mounted type housing <NUM>, the mounting holes <NUM> are formed in a substantially rectangular shape. One rotation restricting groove <NUM> is formed in a lower center of the mounting hole <NUM>, and two rotation restricting grooves <NUM> are formed in the upper portions of both sides of the mounting hole <NUM>. The rotation restricting groove <NUM> at the lower center is formed relatively shallowly, and the rotation restricting grooves <NUM> at the upper portions on both sides are formed relatively deeply. The functions of the rotation restricting grooves <NUM> and <NUM> will be described later with reference to <FIG>.

As shown in <FIG>, in the rack-mounted type housing <NUM>, the mounting hole <NUM> includes a substantially rectangular case hole <NUM> on a back side in a depth direction and a circular seal hole <NUM> in a middle in the depth direction, and a circular spigot hole <NUM> on an end face side. Further, in the upper center of the spigot hole <NUM>, one rotation restricting groove <NUM> is formed continuously with the spigot hole <NUM>. The function of the rotation restricting groove <NUM> will be described later with reference to <FIG>.

It is also possible to manufacture a case dedicated to each of the specifications of the magnetic detection module <NUM> for the two types of housings <NUM> and <NUM> having different shapes and sizes of the mounting portions. However, in that case, two types of resin molding dies are required, and production adjustment and inventory management man-hours for two types of cases are required. Therefore, in the first and second embodiments, it is an object t o provide the magnetic detection module that can be selectively mounted on two types of housings <NUM> and <NUM> having different specifications by a simple configuration change using common components.

Subsequently, a specific configuration of the magnetic detection module of the first embodiment will be described. The first embodiment reflects a basic technical idea regarding case sharing. The second embodiment further includes a magnetic shield member that blocks magnetic noise from the outside as compared with the first embodiment. Hereinafter, with respect to the reference numerals of the detection device and the magnetic detection module of each embodiment, the number of the embodiment is assigned to the third digit following "<NUM>" and "<NUM>". Regarding the reference numerals of the constituent members, in the case of a configuration peculiar to the embodiment, the number of the embodiment is similarly assigned to the third digit, and in the case of substantially the same configuration as the above-described embodiment, the reference numerals of the above-described embodiment are used.

The configurations of the torque detection device <NUM> and the magnetic detection module <NUM> of the first embodiment will be described with reference to <FIG>. The magnetic detection module <NUM> includes a case assembly <NUM> and a cap <NUM>. The case assembly <NUM> includes a case <NUM>, magnetic flux guiding members <NUM>, <NUM>, magnetic sensors <NUM>, <NUM>, a substrate <NUM>, and the like housed in a box portion <NUM> of the case <NUM>. The magnetic flux guiding members <NUM> and <NUM> and the magnetic sensors <NUM> and <NUM> are as described above, as shown in <FIG>. In addition to the magnetic sensors <NUM> and <NUM>, a sensor signal output circuit and the like are mounted on the substrate <NUM>.

The case <NUM> is formed of a resin and has a rectangular parallelepiped box portion <NUM>, a connector portion <NUM> to which a harness for transmitting a signal to an external processing unit is connected, flanges <NUM> formed with fixing holes <NUM> for mounting on the housings <NUM> and <NUM>, and the like. A terminal <NUM> connected to the substrate <NUM> is insert-molded between a bottom of the box portion <NUM> and a bottom of the connector portion <NUM>. The substantially rectangular substrate <NUM> on which the magnetic sensors <NUM> and <NUM> are mounted is installed on the bottom of the box portion <NUM>.

Hereinafter, for convenience of explanation, an opening end <NUM> side of the box portion <NUM> is regarded as upper side, and the bottom side of the box portion <NUM> is regarded as lower side. Further, the side on which the magnetic sensors <NUM> and <NUM> of the box portion <NUM> is mounted is regarded as front side, and the connector portion <NUM> side is regarded as rear side. An end portion of the case <NUM> located on the front side with respect to the flange <NUM> of the box portion <NUM> forms an insertion portion <NUM>. In the column of "Brief description of the drawing", the view seen from the opening end <NUM> side is represented as a plan view, and the view viewed from the insertion portion <NUM> side is represented as a front view. In the following description, "in plan view" is used to mean "when viewed from the opening end <NUM> side".

As shown in <FIG>, etc., the insertion portion <NUM> has a rectangular parallelepiped shape including a front wall <NUM>, side walls <NUM>, and a bottom wall <NUM>. On the edges of the side walls <NUM> on both sides on the opening end <NUM> side, protrusion portions <NUM> are formed as "misassembling prevention portion" and "rotation regulation portion" that project on the upper side. Further, on the lower surface of the box portion <NUM>, a protrusion portion <NUM> as a "misassembling prevention portion" and a "rotation regulating portion" projecting on the lower side is provided at the central portion in the left-right direction and near the flange <NUM> in the front-rear direction.

When the case <NUM> or the cap <NUM> is assembled to the housing <NUM>, the "misassembling prevention portion" can be assembled only in a posture located at a predetermined relative angle, and prevents erroneous assembly in a posture located at a position other than the predetermined relative angle. The "rotation regulation portion" regulates rotation with respect to the housing <NUM> after the case <NUM> or cap <NUM> is assembled to the housing <NUM>.

Each of the set of magnetic flux guiding members <NUM> and <NUM> has a main body <NUM> which has a rectangular band shape in a plan view and collects magnetic flux, and two extensions <NUM> and <NUM> extending in the orthogonal direction from the main body <NUM>. Each of the extensions <NUM> and <NUM> are provided so as to sandwich the magnetic sensors <NUM> and <NUM> in the upper-lower direction. In other words, the magnetic sensors <NUM> and <NUM> are arranged between the set of magnetic flux guiding members <NUM> and <NUM>. In the magnetic flux guiding members <NUM> and <NUM>, at least a part of the main body <NUM> faces the ring portions <NUM>, <NUM> of the cylindrical yokes <NUM> and <NUM> housed in the housing <NUM>, and the magnetic flux is induced from the magnetic circuit formed in the yokes <NUM> and <NUM>. Hereinafter, the rectangular band shape of the magnetic flux guiding members <NUM> and <NUM> are simply referred to as "straight lines". The detailed configuration and operation of the magnetic flux guiding members <NUM> and <NUM> will be described later.

After the magnetic flux guiding embers <NUM> and <NUM>, the magnetic sensors <NUM> and <NUM>, and the substrate <NUM> are housed in the box portion <NUM> of the case <NUM>, the box portion <NUM> of the case <NUM> is potted with molten resin from the opening end <NUM>, and the storage parts are fixed therein. Further, as shown by the broken line in <FIG>, a lid <NUM> that closes the opening end <NUM> may be used as a separate component. In that case, the upper magnetic flux guiding member <NUM> can be insert-molded integrally with the lid <NUM>. In another embodiment, the opening end <NUM> may be closed only by potting the molten resin without using the lid <NUM>, or by using only the lid <NUM> without potting.

In this way, the case assembly <NUM> in which the magnetic flux guiding members <NUM>, <NUM>, the magnetic sensors <NUM>, <NUM>, and the substrate <NUM> are housed in the case <NUM> is configured. The case assembly <NUM> can be independently attached to the non-waterproof housing <NUM>. Further, the case assembly <NUM> can be attached to the waterproof housing <NUM> with the cap <NUM> attached to the insertion portion <NUM>. When the case assembly <NUM> is attached to a non-waterproof housing <NUM>, the case assembly <NUM> alone constitutes a "magnetic detection module". Although the part to which the cap <NUM> is attached is the case assembly <NUM> in the manufacturing process, it can also be expressed as "the cap <NUM> is attached to the case <NUM>" from the viewpoint of each part.

The cap <NUM> is formed of resin, and has a receiving hole <NUM> into which the insertion portion <NUM> of the case <NUM> is inserted, and is formed on an end surface of a disc-shaped cap body <NUM> on the case <NUM> side. The receiving hole <NUM> is opened in a rectangular shape corresponding to the shape of the insertion portion <NUM> of the case <NUM>, and the depth of the receiving hole <NUM> is deeper than the thickness of the cap body <NUM>. The protrusion accommodating grooves <NUM> into which the protrusion portion <NUM> is inserted are formed in the upper portions of both sides of the receiving hole <NUM>. As a result, when the insertion portion <NUM> is inserted into the receiving hole <NUM>, it is prevented from being inserted in a <NUM> ° opposite direction.

On the end face of the cap body <NUM> opposite to the case <NUM>, a sealing portion <NUM> that is connected to the end face and covers the bottom of the receiving hole <NUM> to form a bag is formed. The sealing portion <NUM> protrudes in a rectangular parallelepiped shape from the cap body <NUM> on the side opposite to the case <NUM>, and an outer wall thereof is formed to be larger than an inner wall at the bottom of the receiving hole <NUM> by a predetermined amount. In short, communication is blocked between the outer wall of the sealing portion <NUM> and the inner wall of the receiving hole <NUM> so that water does not leak.

On the outer circumference of the cap body <NUM>, an outer flange portion <NUM> on the opening surface side of the receiving hole <NUM> and an inner flange portion <NUM> on the protruding side of the sealing portion <NUM> are provided in parallel, and an outer peripheral groove <NUM> is formed between the outer flange portion <NUM> and the inner flange portion <NUM>. On the upper center of the outer flange portion <NUM>, a protrusion portion <NUM> protrudes in the outer diameter direction and is formed as a "misassembling prevention portion" and a "rotation regulation portion".

An O-ring <NUM> as a "sealing member" is attached to the outer peripheral groove <NUM>. At this time, an inner peripheral surface of the O-ring <NUM> comes into contact with the bottom wall of the outer peripheral groove <NUM>. The O-ring <NUM> may be mounted on the outer peripheral groove <NUM> before assembling the cap <NUM> and the case <NUM>, or may be mounted on the outer peripheral groove <NUM> after assembling the cap <NUM> and the case <NUM>.

<FIG> shows a torque detection device <NUM> in which the case assembly <NUM> is independently mounted in the mounting hole <NUM> of the non-waterproof housing <NUM>. The insertion portion <NUM> of the case <NUM> is inserted into a substantially rectangular mounting hole <NUM>. At this time, the protrusion <NUM> on the lower side is inserted into the rotation restricting groove <NUM>, and the protrusion portions <NUM> on both upper sides are inserted into the rotation restricting groove <NUM>. Therefore, when the case assembly <NUM> is assembled to the housing <NUM>, it is prevented from being erroneously assembled into the mounting hole <NUM> in the <NUM> ° opposite direction. Further, after being assembled, the rotation of the case assembly <NUM> with respect to the housing <NUM> is restricted.

<FIG> shows the torque detection device <NUM> in which the magnetic detection module <NUM> with the cap <NUM> attached to the case assembly <NUM> is attached to the mounting hole <NUM> of the waterproof housing <NUM>. The sealing portion <NUM> of the cap <NUM> is inserted into the substantially rectangular case hole <NUM>, the inner flange portion <NUM> is inserted into the seal hole <NUM>, and the outer flange portion <NUM> is inserted into the spigot hole <NUM>. At this time, by inserting the protrusion portion <NUM> into the rotation restricting groove <NUM>, when the magnetic detection module <NUM> is assembled to the housing <NUM>, it is prevented from being erroneously assembled to the mounting hole <NUM> in the <NUM> ° opposite direction. Further, after being assembled, the rotation of the magnetic detection module <NUM> with respect to the housing <NUM> is restricted.

The outer peripheral surface of the O-ring <NUM> is pressed against the inner wall of the seal hole <NUM> while being attached to the mounting hole <NUM>. Therefore, as indicated by a bidirectional arrow Cp, the O-ring <NUM> is radially compressed and used for a shaft seal. Compared to face seal, shaft seal is less susceptible to dimensional variations in seal-related parts and tilt during assembly, and has excellent sealing function.

Next, with reference to <FIG>, a modified example of the first embodiment in which the configurations of the "misassembling prevention portion" and the "rotation regulation portion" in the mounting of the cap <NUM> and the housing <NUM> are different will be described. <FIG> and <FIG> are schematic cross-sectional views showing a state in which the cap <NUM> is attached to the housing <NUM>. The schematic cross-sectional view shows a schematic cross-sectional view in which the cap <NUM> and the case <NUM> are combined, and an accurate illustration of the internal structure as shown in <FIG> is omitted. Further, a prismatic portion covered with the bag portion <NUM> protruding from a tip surface of the cap body <NUM> is referred to as "sensor unit <NUM>". The magnetic sensors <NUM> and <NUM> are housed in the sensor unit <NUM>. Here, "being housed" includes a configuration "being molded".

<FIG> and <FIG> are radial cross-sectional views showing a "misassembling prevention portion" and a "rotation regulation portion" provided on the cap <NUM> or the housing <NUM> on the base end side of the cap <NUM>. <FIG> and <FIG> are perspective views of the mounting hole <NUM> of the housing <NUM> corresponding to <FIG>.

In the first modification shown in <FIG>, a protrusion portion <NUM> similar to that in <FIG> is formed on the upper part of the cap body <NUM> and a pair of twin protrusion portions <NUM> are formed at the lower part of the cap body <NUM> so as to project substantially parallel to the outer diameter at predetermined intervals. On the end surface of the housing <NUM>, a rotation regulation convex portion <NUM> interposed between the twin protrusion portions <NUM> is formed. On the other hand, the portion of the end face of the housing <NUM> facing the protrusion portion <NUM> is a flat end face without unevenness.

By assembling the cap <NUM> to the housing <NUM> at the rotation position where the twin protrusion portions <NUM> interpose the rotation regulation convex portion <NUM>, the twin protrusion portion <NUM> functions as a "rotation regulation portion". Further, when assembling the cap <NUM> to the housing <NUM>, if the position in the rotation direction is erroneously assembled by <NUM> °, the protrusion portion <NUM> interferes with the rotation regulation convex portion <NUM> of the housing <NUM>, so that the protrusion portion <NUM> functions as "misassembling prevention portion". As described above, in the first modification, each of the protrusion portion <NUM> and the twin protrusion portions <NUM> of the cap body <NUM> shares the functions of the "misassembling prevention portion" and the "rotation regulation portion" by utilizing the rotation regulation convex portion <NUM> of the housing <NUM>.

In a second modification shown in <FIG>, a protrusion portion <NUM> projecting in the outer diameter direction is formed in a lower portion of the cap body <NUM>. An upper part of the cap body <NUM> is a simple cylindrical surface without unevenness. The housing <NUM> is formed with a rotation restricting groove <NUM> in which the tip of the protrusion portion <NUM> engages with the pedestal portion <NUM> below the mounting hole <NUM>. Further, an interference protrusion portion <NUM> is formed at the edge portion of the mounting hole <NUM> on the side opposite to the rotation restricting groove <NUM>.

By assembling the cap <NUM> to the housing <NUM> at the rotation position where the tip of the protrusion portion <NUM> engages with the rotation restricting groove <NUM>, the protrusion portion <NUM> functions as a "rotation regulation portion". Further, when assembling the cap <NUM> to the housing <NUM>, if the position in the rotation direction is erroneously assembled by <NUM> °, the protrusion portion <NUM> interferes with the interference protrusion portion <NUM> of the housing <NUM>, so that the protrusion portion <NUM> functions as "misassembling prevention portion". As described above, in the second modification, the protrusion portion <NUM> of the cap body <NUM> functions as an "misassembling prevention portion" by utilizing the interference protrusion portion <NUM> of the housing <NUM>, and functions as a "rotation control portion" by utilizing the rotation restricting groove <NUM> of the housing <NUM>.

Next, the configurations of the magnetic flux guiding members <NUM> and <NUM> of the present embodiment will be described with reference to <FIG> are three views of a plan view, a side view, and an axial sectional view, in which a magnetic flux transmission action showing the magnetic flux transmission action between the yokes <NUM> and <NUM>, the magnetic flux guiding members <NUM> and <NUM> and the magnetic sensors <NUM> and <NUM> is shown with the case assembly <NUM> attached to the housing. The plan view means a view seen from the first axis <NUM> side in the axial direction, and the side view means a view seen from the radial direction.

Strictly speaking, the "plan view" is a radial cross-sectional view in which the multipolar magnet <NUM> and the claws <NUM> and <NUM> of the yokes <NUM> and <NUM> are cut at the upper part of the upper magnetic flux guiding member <NUM>, and it is referred to as a "plan view" form the viewpoint of the magnetic flux guiding member <NUM>. Further, although the ring is actually visible only in the lower yoke <NUM> in the radial cross-sectional view, the reference numerals are given as "<NUM>, <NUM>" including the upper yoke <NUM> for convenience of explanation.

In the plan view of <FIG>, a "reference line X" extending in the left-right direction through the central axis O is described. The reference line X is defined as a virtual straight line connecting the intermediate positions of the two magnetic sensors <NUM> and <NUM> and the central axis O. In other words, the two magnetic sensors <NUM>, <NUM> are arranged symmetrically with respect to the reference line X. In the embodiment of one magnetic sensor, the reference line X is defined as a virtual straight line connecting the magnetic sensor and the central axis O.

The side view of <FIG> is a view of the magnetic sensors <NUM> and <NUM> viewed from the outside in the radial direction along the reference line X. The alternate long and short dash line indicates an outer shape of the claws <NUM> and <NUM>. In the side view of <FIG>, the torsion bar <NUM> and the multipolar magnet <NUM> are not shown. The axial sectional view of <FIG> is a cross-sectional view on a plane including the central axis O and the reference line X. In the axial sectional view, the torsion bar <NUM> is not shown, and the multipolar magnet <NUM> shows only the outline.

In the present embodiment, in a plan view, the main bodies of the magnetic flux guiding members <NUM> and <NUM> are formed in a rectangular band shape symmetrical with respect to the reference line X, that is, in a straight line shape. The longitudinal sides of the magnetic flux guiding members <NUM> and <NUM> are straight lines orthogonal to the reference line X.

The magnetic flux guiding members <NUM>, <NUM> have the extensions <NUM> and <NUM> extending radially outward from the main body <NUM>, and the "branch portion of the main body <NUM> to the extensions <NUM> and <NUM>" is referred to as a S portion. The "branch portion to the extensions <NUM> and <NUM>" substantially means the vicinity of the magnetic sensors <NUM> and <NUM>. The "S portion" is the same symbol as the S pole of the multipolar magnet <NUM>, but the distinction between them is obvious and there is no risk of confusion. Portions of each of the main bodies <NUM> of the magnetic flux guiding members <NUM> and <NUM> corresponding to ends of the yokes <NUM> and <NUM> in the circumferential direction across the reference line X within a range where the main bodies <NUM> face the yokes <NUM> and <NUM> are defined as "circumferential end portions <NUM> and <NUM> of the main body <NUM>" and hatched with broken lines in the drawing. A distance ds from the S portion to the central axis O is shorter than the distance de from the circumferential end portions <NUM> and <NUM> to the central axis O.

In the side view and axial-direction sectional view, each of the magnetic flux guiding members <NUM> and <NUM> faces a surface of the ring portion of the corresponding one of the yokes <NUM> and <NUM> from inside of the yokes <NUM> and <NUM> in the axial direction with a constant gap. The area where each of the magnetic flux guiding members <NUM> and <NUM> faces the surface of the ring portion of the corresponding one of the yokes <NUM> and <NUM> (the area hereinafter referred to as the "facing area") is relatively large at a corresponding intermediate portion <NUM> that is close to the magnetic sensors <NUM> and <NUM>, and becomes smaller at locations closer to the corresponding circumferential end portions <NUM> and <NUM>. The S portions, which are locations from which the extensions <NUM> and <NUM> are branched, have larger facing areas than do the circumferential end portions <NUM> and <NUM>, thus having greater magnetic permeance per unit area between each of the magnetic flux guiding members <NUM> and <NUM> and the corresponding one of the yokes <NUM> and <NUM>. Here, "per unit area" is significant in that, when magnetic permeance is compared between different locations, the wording explicitly states that the areas of the locations are the same. In the description of the embodiments provided below where the wording "per unit area" is omitted, it is to be understood that "magnetic permeance" means "magnetic permeance per unit area.

The magnetic sensor <NUM> is disposed between the extensions <NUM>, and the magnetic sensor <NUM> is disposed between the extensions <NUM>. The extensions <NUM> are each bent to have a step in the axial direction so as to have a minimum gap therebetween in a location where the magnetic sensor <NUM> is placed. The extensions <NUM> are each bent to have a step in the axial direction so as to have a minimum gap therebetween in a location where the magnetic sensor <NUM> is placed.

Next, with reference to <FIG>, the reason why the signal becomes large due to the above mentioned configuration will be described. <FIG> shows a correlation diagram between the distance from the reference line X or the rotation angle and the magnetic permeance for the magnetic permeance between the magnetic flux guiding members <NUM>, <NUM> and the yokes <NUM> and <NUM>. The magnetic permeance P is represented by the formula (<NUM>) using a magnetic permeability µ of the material, a facing area A, and a gap length L.

Here, assuming that the magnetic flux guiding members <NUM> and <NUM> are formed of a single soft magnetic material, the larger the facing area A between the magnetic flux guiding members <NUM> and <NUM> and the yokes <NUM> and <NUM>, or a shorter gap length L, results in greater magnetic permeance P. In the present embodiment, the gap between the magnetic flux guiding members <NUM> and <NUM> and the yokes <NUM> and <NUM> is constant, but the facing area becomes smaller from the intermediate portion <NUM> toward the circumferential end portions <NUM> and <NUM>, so that the magnetic permeance of the intermediate portion <NUM> is larger than the magnetic permeance of the circumferential end portions <NUM> and <NUM>. In <FIG>, the correlation characteristic may be any characteristic such as a straight line like P1, a simple curve without an inflection point like P2, an S-shaped curve like P3, or a stepped polygonal line.

The magnetic sensors <NUM> and <NUM> are arranged in the extensions <NUM> and <NUM> branched from the main body <NUM> near the intermediate portion <NUM>, and the branch portion of the magnetic flux guiding members <NUM> and <NUM> to the extensions <NUM> and <NUM> in the main body <NUM> substantially means "vicinity of the magnetic sensors <NUM> and <NUM>". The magnetic flux guiding members <NUM>, <NUM> are configured that the "magnetic permeance per unit area between the magnetic flux guiding members <NUM>, <NUM> and the yokes <NUM> and <NUM>" at the branch portion to the extensions <NUM> and <NUM> is larger than that at the circumferential end portions <NUM> and <NUM>. As a result, the signals of the magnetic sensors <NUM> and <NUM> can be increased.

Next, a method of manufacturing the magnetic detection module will be described with reference to the flowchart of <FIG>. In the description of the flowchart, the symbol S represents a "step". In a storage process of S10, the magnetic flux guiding members <NUM>, <NUM>, the magnetic sensors <NUM>, <NUM>, the substrate <NUM>, and the like are housed in the box portion <NUM> of the case <NUM>. Then, for example, the molten resin is potted in the remaining space of the box portion <NUM>, and the magnetic sensors <NUM> and <NUM> are fixed. Further, the box portion <NUM> may be covered with a lid <NUM>. In this way, the case assembly <NUM> is manufactured in the storage process S10.

In a selection process of S20, according to the specifications of the housing to be attached, it is selected whether to use the case assembly <NUM> alone or to attach a cap <NUM> set for each housing specification to the end of the case <NUM>. In the first embodiment, it is determined whether the case assembly <NUM> is attached to the non-waterproof housing <NUM> that does not require the sealing member or the waterproof housing <NUM> that requires the sealing member.

In S25, the selection result is determined. When the case assembly <NUM> is attached to the waterproof housing <NUM>, it is determined as YES in S25, and the process proceeds to the attachment process of S30. When the case assembly <NUM> is attached to the non-waterproof housing <NUM>, it is determined as NO in S25, and the process ends. In this case, the case assembly <NUM> is used alone without the cap <NUM> being attached.

In a mounting process of S30, the cap <NUM> is mounted and fixed to the case <NUM>. In the configuration of the first embodiment, the insertion portion <NUM> formed at the end of the case <NUM> is inserted into the receiving hole <NUM> formed in the cap <NUM>. After that, a joint portion between the insertion portion <NUM> of the case <NUM> and the receiving hole <NUM> of the cap <NUM> is welded by laser welding or the like. Here, even in a configuration in which the sealing portion <NUM> that covers the bottom of the receiving hole <NUM> to form a bag as shown in <FIG> is not provided, the joint portion surrounding the magnetic sensors <NUM> and <NUM> is welded all around. Therefore, water leakage from the bottom of the receiving hole <NUM> can be prevented.

The cap <NUM> may be fixed with an adhesive in the mounting process. When the molten resin is potted in the storage step, it is preferable that the potting is cured and the adhesive is cured at the same time. As a result, the cycle time can be shortened.

As described above, the magnetic detection module <NUM> of the first embodiment can change the mounting specifications to the housing <NUM> depending on the presence or absence of the cap <NUM>. Specifically, for the waterproof housing <NUM>, a magnetic detection module in which the cap <NUM> provided with the sealing member <NUM> is attached to the case <NUM> is supplied. Further, for the non-waterproof housing <NUM>, the case assembly <NUM> without the cap <NUM> is independently supplied as a magnetic detection module. Therefore, for example, when the case <NUM> is manufactured by resin molding, only one type of mold is required for the case <NUM>, and inventory management is simplified.

Next, with reference to <FIG>, a magnetic detection module <NUM> of the second embodiment provided with the magnetic shield member will be described. The magnetic shield member is made of a soft magnetic material such as iron or permalloy, and blocks magnetic noise from the outside.

In the form shown in <FIG>, a rectangular frame-shaped magnetic shield member <NUM> is provided at the insertion portion <NUM> of the case assembly <NUM> that is independently attached to the non-waterproof housing <NUM>. Specifically, after the molten resin is potted on the case <NUM>, the magnetic shield member <NUM> is covered so as to surround the magnetic sensors <NUM> and <NUM> from all sides. Therefore, the magnetic noise directed to the magnetic sensors <NUM> and <NUM> is effectively blocked.

In the form shown in <FIG>, a pair of arch-shaped magnetic shield members <NUM> are provided on the cap <NUM> of the magnetic detection module <NUM> attached to the waterproof housing <NUM>. The pair of magnetic shield members <NUM> are provided so as to surround the sealing portion <NUM> from the upper-lower direction. As shown in <FIG>, the magnetic shield member <NUM> is arranged so that a center line Ds in the depth direction overlaps the magnetic sensors <NUM> and <NUM>. Therefore, the magnetic noise directed to the magnetic sensors <NUM> and <NUM> is effectively blocked.

Next, a third embodiment will be described with reference to <FIG>. A torque detection device <NUM> of the third embodiment includes a housing <NUM> having a mounting hole <NUM> whose inner wall is cylindrical, and a magnetic detection module <NUM> mounted in the mounting hole <NUM>. Although not shown in <FIG>, a set of yokes <NUM> and <NUM> for transmitting magnetic flux generated according to the magnitude of torque is provided inside the housing <NUM>. The magnetic detection module <NUM> detects the magnetic flux transmitted from the yokes <NUM> and <NUM> with one or more magnetic sensors <NUM> and <NUM>.

Similar to the first embodiment, the magnetic detection module <NUM> of the third embodiment has a disc-shaped cap <NUM> attached to the tip of the case <NUM>. An outer peripheral surface of the cap body <NUM> in the cap <NUM> faces the inner wall of the mounting hole <NUM>. However, in the cap <NUM> of the first embodiment, the outer peripheral groove <NUM> is formed between the outer flange portion <NUM> and the inner flange portion <NUM>. On the other hand, the cap <NUM> of the third embodiment is not provided with an inner flange portion, and a step portion <NUM> in the radial direction is formed on the outer periphery. In the example of <FIG>, the O-ring <NUM> as a sealing member for the shaft seal is attached to the step portion <NUM>, but in other embodiments, the O-ring <NUM> may not be provided. The step portion <NUM> is composed of a step between a large diameter portion <NUM> on the base end side of the cap body <NUM> and a small diameter portion <NUM> on the tip end side thereof. The large diameter portion <NUM> and the small diameter portion <NUM> correspond to the "large shaft portion" and the "small shaft portion".

The mounting hole <NUM> has a case hole <NUM>, a small diameter hole <NUM>, a large diameter hole <NUM>, and a chamfered portion <NUM> in order from the back with respect to the end surface <NUM> side. The large diameter hole <NUM> and the small diameter hole <NUM> correspond to the "large hole" and the "small hole". The large diameter portion <NUM> of the cap <NUM> is inserted into the large diameter hole <NUM>, and the small diameter portion <NUM> is inserted into the small diameter hole <NUM>. On the base end side of the large diameter portion <NUM>, a flange portion <NUM> that abuts on an end surface <NUM> of the housing <NUM> is formed. Further, the sensor unit <NUM> projects from the tip surface of the cap body <NUM>. The tip of the sensor unit <NUM> is inserted between the ring portions <NUM>, <NUM> of the set of yokes <NUM>, <NUM>.

In the torque detection device <NUM> of the third embodiment, the dimensional relationship of the fitting gap between the large diameter portion <NUM> and the large diameter hole <NUM> or the small diameter portion <NUM> and the small diameter hole <NUM> and the gap between the sensor unit <NUM> and the ring portion of the yoke is adjusted appropriately. Since the configuration and the effect regarding the dimensional relationship are the same as the configuration and the effect of the torque detection device <NUM> of the following fourth embodiment, they will be described together in the fourth embodiment.

Next, a fourth embodiment will be described with reference to <FIG>. A torque detection device <NUM> of the third embodiment includes the housing <NUM> having the mounting hole <NUM> whose inner wall is cylindrical, and a magnetic detection module <NUM> mounted in the mounting hole <NUM>. Similar to the third embodiment, a set of yokes <NUM> and <NUM> for transmitting magnetic flux generated according to the magnitude of torque is provided inside the housing <NUM>. The magnetic detection module <NUM> detects the magnetic flux transmitted from the yokes <NUM> and <NUM> with one or more magnetic sensors <NUM> and <NUM>.

The magnetic detection module <NUM> is not intended to be selectively mountable to a plurality of housings, and the mounting target is limited to the housing <NUM> having a mounting hole <NUM> whose inner wall is cylindrical. The fourth embodiment aims to prevent interference between the sensor unit <NUM> and the member on the housing <NUM> side when the magnetic detection module <NUM> is inserted into the housing <NUM>. Therefore, the magnetic detection module <NUM> of the fourth embodiment is not configured to have a cap of another member attached to the end portion of the case, but is configured by an integrated case <NUM>. The case <NUM> is integrally formed of resin in a shape equivalent to the state in which the cap <NUM> is attached to the case <NUM> in the third embodiment shown in <FIG>. That is, the one in which the case <NUM> and the cap <NUM> are combined is the integrated case <NUM> of the fourth embodiment.

A portion corresponding to the cap body <NUM> of the cap <NUM> of the third embodiment is referred to as a "cylindrical portion <NUM>" in the fourth embodiment. The cylindrical portion <NUM> corresponds to the "cylindrical portion" and faces the inner wall of the mounting hole <NUM>. Further, the sensor unit <NUM> projects from the tip surface of the cylindrical portion <NUM>. In other words, the form in which the cylindrical portion <NUM> of the case <NUM> of the fourth embodiment is composed of the cap body <NUM> of the cap <NUM> of another member corresponds to the third embodiment. In short, the form in which the O-ring <NUM> is mounted in the third embodiment has both purposes, "selective mounting to a plurality of housings of waterproof and non-waterproof specifications" and "prevention of interference between the magnetic sensor and the housing side member".

Therefore, the configuration of the cylindrical portion <NUM> and the mounting hole <NUM> facing the cylindrical portion <NUM> of the fourth embodiment is substantially the same as the configuration of the cap main body <NUM> and the mounting hole <NUM> facing the outer peripheral surface of the cap main body <NUM> of the third embodiment. The mounting hole <NUM> has a large-diameter hole <NUM> formed on the opening side and a small diameter hole <NUM> formed at the back of the large-diameter hole <NUM>.

The cylindrical portion <NUM> has a flange portion <NUM> that abuts on the end surface <NUM> of the housing from the base end side toward the tip end side where the magnetic sensors <NUM> and <NUM> are arranged, a large diameter portion <NUM> that is inserted into the large diameter hole <NUM>, and a small diameter portion <NUM> that is inserted into the small diameter hole <NUM>. In the example of <FIG>, the O-ring <NUM> is attached to the outer periphery of the small diameter portion <NUM> as a sealing member, but in other embodiments, the O-ring <NUM> may not be provided. The O-ring <NUM> is used for a shaft seal with respect to the inner wall of the small diameter hole <NUM>.

Next, with reference to <FIG> and <FIG>, the dimensional relationship between the cap body <NUM> and the inner diameter of the mounting hole <NUM> in the torque detection device <NUM> of the third embodiment, or the dimensional relationship between the outer diameter of the cylindrical portion <NUM> and the inner diameter of the mounting hole <NUM> in the torque detection device <NUM> of the fourth embodiment. In the description of this part, terms such as "cylindrical portion <NUM>" of the fourth embodiment are used as representatives. Regarding the third embodiment, for example, "cylindrical portion <NUM>" may be read as "cap body <NUM>".

The cross-sectional view of the torque detection device <NUM> of <FIG> and <FIG> is schematic as in <FIG> and <FIG>. The magnetic sensors <NUM> and <NUM> are housed in the "sensor unit <NUM>" which is a prismatic portion protruding from the tip surface of the cylindrical portion <NUM>. Here, "being housed" includes a configuration "being molded". If the sensor unit <NUM> interferes with the member on the housing <NUM> side due to misalignment or inclination when the magnetic detection module <NUM> is inserted into the mounting hole <NUM>, the magnetic sensors <NUM> and <NUM> may be damaged or their characteristics may change. Therefore, in the fourth embodiment, interference between the sensor unit <NUM> and the member on the housing <NUM> side is prevented.

Specifically, the sensor unit <NUM> is inserted between the ring portions <NUM>, <NUM> of the pair of yokes <NUM>, <NUM> facing each other. The magnetic flux generated between the ring portions <NUM> and <NUM> passes through the sensor unit <NUM>, so that the magnetic sensors <NUM> and <NUM> detect the magnetic flux. The minimum distance between the sensor unit <NUM> and the ring portions <NUM> and <NUM> is defined as "sensor margin µ". As shown in <FIG> and <FIG>, when the position of the sensor unit <NUM> is not biased with respect to the center of the ring portions <NUM> and <NUM>, the sensor margin µ is half the length obtained by subtracting the thickness of the sensor unit <NUM> from the distance between the ring portions <NUM> and <NUM>.

<FIG> and <FIG> show examples of two patterns having different dimensional relationships regarding diameter. The dimensional symbols for each part are defined as follows. A "one-sided fitting gap" corresponds to one half of the fitting gap between the diameter of the hole and the diameter of the shaft. The letter "h" in the symbol represents the housing and the "s" represents the sensor.

In the embodiment shown in <FIG>, the one-sided fitting gap ε1 between the large diameter hole <NUM> and the large diameter portion <NUM> is set to, for example, a minute gap of less than <NUM>. That is, the fitting of the large diameter hole <NUM> and the large diameter portion <NUM> has the spigot structure. Therefore, accuracy such as coaxiality and squareness when the cylindrical portion <NUM> is inserted into the mounting hole <NUM> is ensured. Further, the gap ε1 is set smaller than the sensor margin µ (ε1 < µ). Preferably, the gap ε1 is set to be much smaller than the sensor margin µ (ε1 << µ). The one-side fitting gap ε2 between the small diameter hole <NUM> and the small diameter portion <NUM> may be equal to or larger than the gap ε1.

Regarding the axial dimensions of the cylindrical portion <NUM> and the mounting hole <NUM> in this configuration, the distance from the insertion end of the large diameter hole <NUM> (that is, the boundary between the chamfered portion <NUM> and the large diameter hole <NUM>) to the outer edge of the ring portions <NUM> and <NUM> of the yokes <NUM> and <NUM> is defined as "housing side distance Lh1". Further, the distance from the boundary between the large diameter portion <NUM> and the small diameter portion <NUM> to the tip of the sensor unit <NUM> is defined as "sensor side distance Ls1". The housing side distance Lh1 is set longer than the sensor side distance Ls1.

With such a dimensional setting, even if the shaft of the cylindrical portion <NUM> is tilted to the maximum with respect to the shaft of the mounting hole <NUM> and the outer wall of the large diameter portion <NUM> contacts the inner wall of the large diameter hole <NUM> on one side in the circumferential direction, the fluctuation of the tip position of the sensor unit <NUM> is suppressed to be smaller than the sensor margin µ. Therefore, when the magnetic detection module is inserted, it is possible to prevent the sensor unit <NUM> from interfering with the yokes <NUM> and <NUM> which are housing side members.

In the embodiment shown in <FIG>, the one-sided fitting gap ε2 between the small diameter hole <NUM> and the small diameter portion <NUM> is set to, for example, a minute gap of less than <NUM>. That is, the fitting of the small diameter hole <NUM> and the small diameter portion <NUM> has the spigot structure. Therefore, accuracy such as coaxiality and squareness when the cylindrical portion <NUM> is inserted into the mounting hole <NUM> is ensured. Further, the gap ε2 is set to be smaller than the sensor margin µ (ε2 < µ). Preferably, the gap ε2 is set to be much smaller than the sensor margin µ (ε2 << µ). The one-side fitting gap ε1 between the large diameter hole <NUM> and the large diameter portion <NUM> may be equal to or larger than the gap ε2.

Regarding the axial dimensions of the cylindrical portion <NUM> and the mounting hole <NUM> in this configuration, the distance from the insertion end of the small diameter hole <NUM> (that is, the boundary between the large diameter hole <NUM> and the small diameter hole <NUM>) to the outer edges of the ring portions <NUM> and <NUM> of the yokes <NUM> and <NUM> is defined as "housing side distance Lh2". Further, the distance from the tip surface of the cylindrical portion <NUM> to the tip of the sensor unit <NUM> is defined as "sensor side distance Ls2". The housing side distance Lh2 is set longer than the sensor side distance Ls2.

With such a dimensional setting, even if the shaft of the cylindrical portion <NUM> is tilted to the maximum with respect to the shaft of the mounting hole <NUM> and the outer wall of the small diameter portion <NUM> contacts the inner wall of the small diameter hole <NUM> on one side in the circumferential direction, the fluctuation of the tip position of the sensor unit <NUM> is suppressed to be smaller than the sensor margin µ. Therefore, when the magnetic detection module is inserted, it is possible to prevent the sensor unit <NUM> from interfering with the yokes <NUM> and <NUM> which are housing side members.

Next, with reference to <FIG>, a configuration for restricting rotation and preventing erroneous assembly of the cylindrical portion <NUM> with respect to the mounting hole <NUM> will be described. For example, in the prior art of Patent Document <NUM> (Patent No. <CIT>), the magnetic ring is arranged in the outer diameter direction of the magnetic yoke and faces the magnetic yoke in the radial direction. In this configuration, it is effective to secure the concentricity between the magnetic ring and the magnetic yoke by positioning, but the position accuracy in the rotation direction does not significantly affect the performance. On the other hand, in the torque detection device <NUM> of the fourth embodiment in which the magnetic sensors <NUM> and <NUM> are arranged between the ring portions <NUM> and <NUM> of the set of yokes <NUM> and <NUM>, positioning of the cylindrical portion <NUM> with respect to the mounting hole <NUM> in the rotational direction is important. Further, it is important to prevent the magnetic detection module <NUM> from being assembled in the wrong direction by, for example, <NUM> °.

<FIG>, <FIG>, and <FIG> show the cross section of the cylindrical portion <NUM> in the cross section taken along the line A-A of <FIG> and <FIG>. <FIG>, <FIG>, and <FIG> show the front view of the mounting hole of the housing according to the arrow in the B direction in <FIG> and <FIG>. The parts where the assembly cross sections of <FIG> and <FIG> are changed according to each of the shapes of <FIG> are not shown. Further, for example, when used for a column-mounted type that does not require waterproofing, the O-ring <NUM> may be eliminated in each figure.

In the example shown in <FIG>, a protrusion portion <NUM> protruding in the outer diameter direction is formed at one position in the circumferential direction of the large diameter portion <NUM>. Further, a rotation restricting groove <NUM> is formed at a corresponding portion of the mounting hole <NUM>. This configuration example is similar to the configuration example of the protrusion portion <NUM> and the rotation regulation portion <NUM> in <FIG>, <FIG> and the like. However, in the example of <FIG>, the protrusion portion <NUM> is formed on the outer periphery of the outer flange portion <NUM> inserted into the spigot hole <NUM>, whereas the example of <FIG> is different in that the protrusion portion <NUM> is formed on the outer periphery of the large diameter portion <NUM>. As described above, there is no essential difference regardless of which part of the outer peripheral surface of the cylindrical portion <NUM> the protrusion is formed.

In this example, the rotation of the cylindrical portion <NUM> is restricted by engaging the protrusion portion <NUM> with the rotation restricting groove <NUM>. Further, it is possible to assemble only in a posture in which the relative angle between the cylindrical portion <NUM> and the mounting hole <NUM> is located at a regular angle, and the erroneous assembly is prevented in a posture located at a posture other than the predetermined relative angle. In this way, the protrusion portion <NUM> and the rotation restricting groove <NUM> function as both a "misassembling prevention portion" and a "rotation regulation portion".

In the example shown in <FIG>, a flat portion <NUM> is formed on one side of the large diameter portion <NUM> in the circumferential direction. Further, a rotation restricting recess <NUM> is formed at a corresponding portion of the mounting hole <NUM>. The flat portion <NUM> corresponds to a form in which the width of the protrusion portion <NUM> is widened and the protrusion length with respect to the outer diameter of the large diameter portion <NUM> is shortened. In the example of <FIG>, the protrusion length of the flat portion <NUM> with respect to the outer diameter of the large diameter portion <NUM> is set to be substantially <NUM>. Further, the flat portion <NUM> may be formed on the minus side (that is, the center side) with respect to the outer diameter of the large diameter portion <NUM>, and the outer peripheral shape of the large diameter portion <NUM> may be a D shape in which a part in the circumferential direction is connected by a straight line. In this example, when the flat portion <NUM> engages with the rotation restricting recess <NUM>, the flat portion <NUM> and the rotation restricting recess <NUM> function as both a "misassembling prevention portion" and a "rotation regulation portion".

In the example shown in <FIG>, a separation portion <NUM> is formed at a position separated in the outer diameter direction from the circular large diameter portion <NUM>. The separation portion <NUM> is connected to a collar portion <NUM> via a connecting portion <NUM> indicated by the alternate long and short dash line. Further, a rotation restricting hole <NUM> is formed at a corresponding portion of the mounting hole <NUM>. For example, when the rotation control hole <NUM> is formed in the housing <NUM> by post-processing, the processing is easy because the shape is simple. In this example, the separation portion <NUM> is fitted into the rotation restricting hole <NUM>, so that the separation portion <NUM> and the rotation restricting hole <NUM> function as both the "misassembling prevention portion" and the "rotation regulation portion".

Claim 1:
A magnetic detection module (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) that is provided so as to be selectively mountable in any of a first and a second housing (<NUM>, <NUM>, <NUM>), the first housing having a first specification, the second housing having a second specification, the first and second housings having different shapes or sizes of mounting portions, and detects magnetic flux generated in the housing (<NUM>, <NUM>, <NUM>), comprising:
one or more magnetic sensors (<NUM>, <NUM>) configured to detect magnetic flux;
a case (<NUM>, <NUM>) in which the magnetic sensor (<NUM>, <NUM>) is housed; and
a cap (<NUM>, <NUM>, <NUM>) that is attachable to an end of the case (<NUM>, <NUM>) and has a sealing member (<NUM>),
wherein
the magnetic detection module (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) configured to be attachable to the housing (<NUM>) of the first specification with the cap (<NUM>, <NUM>, <NUM>) not attached to the case (<NUM>, <NUM>), and to be attachable to the housing (<NUM>) of the second specification through the sealing member (<NUM>) with the cap (<NUM>, <NUM>, <NUM>) attached to the case (<NUM>, <NUM>),
the end of the case (<NUM>, (<NUM>) forming an insertion portion (<NUM>) for insertion into a mounting hole (<NUM>) of the first housing (<NUM>) in case of mounting to the first housing (<NUM>), and for insertion into a receiving hole (<NUM>) of the cap (<NUM>, <NUM>, <NUM>) in case of mounting to the second housing (<NUM>),
the cap (<NUM>, <NUM>, <NUM>) being configured to be inserted into a mounting hole (<NUM>) of the second housing (<NUM>), and
the case (<NUM>, <NUM>) has a connector portion (<NUM>) for transmitting a signal to an external processing unit and flanges (<NUM>) formed with fixing holes (<NUM>) for mounting on the first and second housings (<NUM>, <NUM>), respectively.