Sensor device

Abstract

This sensor device (100) acquires a measurement value of an instrument (G1) having: a magnet (G18) that rotates together with a pointer (G14) around an axis (AX) of a shaft member (G17) orthogonal to a scale-marked scale surface (G16a) of a scale plate (G16); and a transparent plate (G15) that covers the scale plate (G16), the pointer (G14), and the magnet (G18). The sensor device (100) comprises: a sensor device body (D1) that is disposed so as to overlap the axis (AX) when viewed in a direction along an axial direction (Z) of the axis (AX), has a sensor unit (21) for acquiring position information about the magnet (G18), and acquires a measurement value on the basis of the position information; and an attachment unit (A1) for attaching the sensor device body (D1) to the instrument (G1).

Description

Sensor Device

[0001] The present disclosure relates to a sensor device.

[0002] In recent years, automation has progressed in manufacturing factories, and the use of robots (robotic devices) for product assembly, product inspection, and other tasks has been increasing. Such robotic devices are equipped with numerous instruments for monitoring their operational status. For example, the operational status of the robotic devices is monitored by workers reading the scales indicated by pointers. However, since many instruments are often distributed throughout a factory, manually reading the measured values ​​of multiple instruments one by one is cumbersome. To address this issue, Patent Literature 1 (JP-A-2005-102262) discloses an instrument sensor that collects data from multiple instruments and transmits it to an external device without the need for workers. The instrument sensor is attached to the transparent cover of the instrument with double-sided tape. An image of the pointer captured by the instrument sensor's camera is analyzed by an image analyzer to obtain the pointer angle, and data on the pointer angle or a value corresponding to the pointer angle is transmitted to the external device.

[0003] Japanese Patent Application Laid-Open No. 2022-32602

[0004] However, when the sensor is attached to the meter using double-sided tape, as in the case of the meter sensor disclosed in Patent Document 1, the double-sided tape is interposed between the sensor and the meter, which may reduce the accuracy of the sensor.

[0005] Therefore, there is a need for a sensor device that can suppress the deterioration of sensor accuracy.

[0006] A characteristic configuration of the sensor device according to the present disclosure is a sensor device that acquires measurement values ​​of an instrument having a magnet that rotates together with a pointer around the axis of an axis member that is perpendicular to the scale surface on which the scale is formed of a scale plate, and a transparent plate that covers the scale plate, the pointer, and the magnet, and that comprises: a sensor device main body that is arranged so as to overlap with the axis when viewed in the axial direction along the axis, has a sensor unit that acquires position information of the magnet and acquires the measurement values ​​based on the position information; and an attachment unit for attaching the sensor device main body to the instrument, and the attachment unit is fixed to the transparent plate so as not to overlap with the sensor unit when viewed in the axial direction.

[0007] With this characteristic configuration, the mounting portion does not overlap with the sensor portion when viewed from the axial direction, allowing the sensor portion to be closer to the magnet. Furthermore, variations in the distance between the sensor portion and the magnet due to variations in the dimensional accuracy of the mounting portion and / or the mounting state can be reduced. Therefore, deterioration in the accuracy of the sensor portion can be suppressed.

[0008] Furthermore, the mounting portion has an opposing portion that faces the transparent plate, and a protruding portion that has the opposing portion as its base end and protrudes in an axial direction along the axis away from the sensor device main body, and it is preferable that the mounting portion be fixed to the transparent plate by welding the protruding portion to the transparent plate.

[0009] With this configuration, the mounting portion is fixed to the transparent plate by welding the protrusion, so there is no need to use separate materials such as double-sided tape or adhesive to mount the sensor device main body to the instrument.

[0010] Furthermore, it is preferable that the sensor device main body further has a main body case that houses the sensor unit, the main body case including a first space that is open on one side in the axial direction along the axis, and the mounting portion is configured separately from the main body case and at least a portion of it is housed in the first space.

[0011] With this configuration, the attachment portion, which is separate from the main body case, is housed in the main body case. That is, the attachment portion is disposed inside the main body case, so that the sensor device can be prevented from becoming large.

[0012] Preferably, the main body case further includes a second space that houses the sensor unit, and the first space and the second space are separated from each other.

[0013] With this configuration, it is possible to prevent water, dust, etc. from entering the second space through the first space as an inlet.

[0014] Furthermore, it is preferable that the sensor device main body further has a main body case that houses the sensor unit, the mounting portion is configured separately from the main body case, and further has an engaging portion that is externally fitted onto the main body case in the axial direction along the axis, and the main body case includes a fitted portion that is fitted into the engaging portion.

[0015] With this configuration, the mounting portion fits onto the exterior of the main body case, so the mounting portion is not hidden by the fitted portion of the main body case, and the main body case can be fixed to the mounting portion, thereby improving the efficiency of the work of attaching the main body case to the mounting portion.

[0016] Furthermore, it is preferable that the sensor device main body includes a main body facing portion that faces the transparent plate and further has a main body case that houses the sensor portion, and that the mounting portion is formed integrally with the main body case and includes an mounting shaft that protrudes beyond the main body facing portion, and that the mounting shaft is fitted into a through hole that passes through the transparent plate, thereby fixing the main body case to the transparent plate.

[0017] With this configuration, the mounting portion is integral with the main body case, so that the sensor device can be easily mounted on the transparent plate without using a separate mounting portion.

[0018] In addition, the sensor device main body further has a battery case that houses a battery that generates electricity to be supplied to the sensor unit, and it is preferable that the battery case be separable from the main body case and be positioned on the side of the main body case that is farther from the transparent plate.

[0019] With this configuration, it is possible to replace the battery housed in the battery case while the main body case remains attached to the transparent plate.

[0020] Preferably, the sensor unit includes a magnetic sensor.

[0021] With this configuration, by using a general-purpose magnetic sensor as the sensor section, it is possible to easily realize a sensor device that acquires the measurement value of the meter without contacting the pointer.

[0022] 1 is a diagram showing a sensor device and a meter according to the first embodiment; 2 is an exploded perspective view of the meter shown in FIG. 1; 3 is an exploded perspective view of the main body shown in FIG. 1; 4 is an exploded perspective view of the main body seen from an angle different from that of FIG. 3; 5 is a cross-sectional view taken along line V-V shown in FIG. 1; 6 is an exploded perspective view of the sensor device shown in FIG. 1; 7 is a perspective view of the mounting section according to the first embodiment; 8 is a plan view of the mounting section shown in FIG. 7; 9 is a side view of the mounting section shown in FIG. 7; 10 is a perspective view of a modified mounting section according to the first embodiment; 11 is a perspective view of the mounting section and the main body shown in FIG. 10; 12 is a view of the main body to which the mounting section shown in FIG. 11 is attached; 12 is a perspective view of the mounting section and the main body according to the second embodiment; 13 is a perspective view of the mounting section and the main body seen from an angle different from that of FIG. 13; 14 is a perspective view of a modified mounting section according to the second embodiment; 15 is a perspective view of the configuration of the sensor device according to the third embodiment; 16 is a perspective view of the sensor device seen from an angle different from that of FIG. 16.

[0023] The sensor device according to the embodiment of the present disclosure will be described below. Note that the components of the embodiments described below can be combined with each other as long as they are not inconsistent. Furthermore, the materials, shapes, dimensions, numbers, and arrangements of the components in each aspect of the embodiments described below are merely examples, and any design modifications are possible as long as the same functions can be achieved.

[0024] First Embodiment An overview of a sensor device 100 will be described below with reference to Fig. 1. Fig. 1 is a diagram showing the sensor device 100 and a meter G1. As shown in Fig. 1, the sensor device 100 is attached to the meter G1 and acquires measurements of the meter G1. The meter G1 is placed in a factory that includes a device to be inspected, for example, to monitor the operating status of the device to be inspected.

[0025] [Gauge] The gauge G1 is an analog gauge. In this embodiment, the gauge G1 is a pressure gauge for measuring the pressure of a fluid F, such as air, injected through an inlet of the gauge body G11. The gauge G1 is, for example, a Bourdon tube pressure gauge according to "JIS 7505-1 Aneroid Pressure Gauges - Part 1: Bourdon Tube Pressure System." Note that the gauge G1 is not limited to a pressure gauge as long as it is an analog gauge.

[0026] As shown in Figure 2, the meter G1 includes a meter main body G11, a housing G12, an outer frame G13, a pointer G14, a transparent plate G15, a scale plate G16, a shaft member G17, and a magnet G18. In the following description, the direction along the axis AX of the shaft member G17 will be referred to as the axial direction Z. When the sensor device 100 is attached to the meter G1, one side of the axial direction Z (the meter G1 side) will be referred to as the "one axial direction side Z1," and the other side of the axial direction (the sensor device 100 side) will be referred to as the "other axial direction side Z2." Therefore, the direction in which the sensor device 100 is arranged relative to the meter G1 (the stacking direction) corresponds to the other axial direction side Z2.

[0027] The meter body G11 is housed in the housing G12 together with the pointer G14, the scale plate G16, the shaft member G17, and the magnet G18. The meter body G11 is configured so that the pointer G14 indicates a value corresponding to the pressure of the fluid F (a scale G161 on the scale plate G16).

[0028] The pointer G14 is disposed between the transparent plate G15 and the scale plate G16 in the axial direction Z.

[0029] The transparent plate G15 is a flat plate-shaped member made of translucent glass, translucent resin, or the like. The transparent plate G15 is fitted into the outer frame G13 and incorporated into the housing G12. When incorporated into the housing G12, the transparent plate G15 covers the pointer G14, the scale plate G16, the shaft member G17, and the magnet G18.

[0030] A scale G161 for indicating a value corresponding to the pressure of the fluid F (measured value) is provided on the surface of the scale plate G16 facing the transparent plate G15.

[0031] The shaft member G17 is disposed so as to be perpendicular to the scale surface G16a on which the scale G161 of the scale plate G16 is provided. The shaft member G17 is supported by the housing G12 so as to be rotatable about the axis AX. When the fluid F flows in through the inlet of the meter body G11, the shaft member G17 rotates about the axis AX. In this embodiment, the shaft member G17 penetrates the scale plate G16 along the axial direction Z. One end of the shaft member G17 is connected to the meter body G11, and the pointer G14 is fixed to the other end.

[0032] The pointer G14 extends radially outward from the shaft member G17. The pointer G14 rotates in conjunction with the rotation of the shaft member G17 (the pointer G14 moves together with the shaft member G17). As a result, the tip of the pointer G14 points to a scale G161 that corresponds to the pressure of the fluid F that has flowed into the meter body G11. The operator can check the scale G161 (measurement value of the meter G1) indicated by the pointer G14 through the transparent plate G15.

[0033] The magnet G18 is fixed to the shaft member G17 between the pointer G14 and the transparent plate G15. The magnet G18 rotates together with the pointer G14 around the axis AX (the magnet G18 moves together with the pointer G14). The magnet G18 has at least two magnetic poles when viewed in a direction along the axial direction Z (hereinafter also referred to as "viewed from the axial direction Z"). In this embodiment, the magnet G18 is circular when viewed from the axial direction Z, and one semicircular north pole and one semicircular south pole are arranged thereon.

[0034] The sensor device 100 detects the direction of the magnetic field and the magnitude of the magnetic force generated by the magnet G18 to obtain information (hereinafter referred to as "position information") indicating the position of the magnet G18 (on the scale plate G16 of the pointer G14), and obtains the measurement value of the meter G1 based on the obtained position information. Note that the sensor device 100 can obtain the measurement value without contacting the pointer G14, i.e., without contacting the pointer G14.

[0035] As shown in Fig. 2, the sensor device 100 includes a sensor device main body D1 and an attachment part A1. The attachment part A1 is a member for attaching the sensor device main body D1 to the meter G1. In this embodiment, the attachment part A1 is configured separately from the sensor device main body D1 (see Fig. 6).

[0036] [Sensor Device Main Body] The sensor device main body D1 has a main body section M1 and a battery section B1. The main body section M1 is arranged closer to the meter G1 than the battery section B1 (one axial side Z1).

[0037] [Main Unit] The main unit M1 acquires the measurement values ​​of the meter G1. As shown in Fig. 3, the main unit M1 has a main unit case 1, a sensor circuit 2, a wireless circuit 3, and a main unit board 4.

[0038] The main body case 1 has a cylindrical (circular when viewed in the axial direction Z) main body tube portion 11 with a bottom, and a main body protrusion portion 12 that protrudes radially outward from the outer surface of the main body tube portion 11.

[0039] The tubular main body portion 11 includes a main body bottom surface portion 111 (an example of a main body facing portion), a main body outer peripheral portion 112, and a first main body space 11S (see FIG. 3). The first main body space 11S is an example of a second space.

[0040] 4, the main body bottom portion 111 has a main body facing surface 111a that faces the transparent plate G15 when the sensor device main body D1 is attached to the instrument G1. The main body facing surface 111a is a plane (flat surface) that is perpendicular to the axial direction Z.

[0041] The main body outer periphery 112 is circular when viewed in the axial direction Z, and extends from the main body bottom surface 111 in a direction perpendicular to the main body facing surface 111a (the other axial direction side Z2).

[0042] 3, the first body space 11S is a space defined by the body bottom surface 111 and the body outer peripheral surface 112. The first body space 11S is open on the side facing the body-facing surface 111a (the other axial side Z2). The first body space 11S accommodates the body board 4 on which the sensor circuit 2 and the wireless circuit 3 are mounted.

[0043] The first body space 11S is configured to be liquid-tight. The first body space 11S is filled with, for example, an insulating first filler P1 (see FIG. 5 ). This makes the main body M1 explosion-proof. The explosion-proof specification refers to a specification that prevents the sensor device 100 from becoming an ignition source for flammable materials (gas, dust, etc.) located outside the sensor device 100. Methods for achieving explosion-proof specifications include filling the first body space 11S with the first filler P1, ensuring insulation distances in spaces where potential differences occur, on component surfaces, applying a resin material such as a potting agent to the target component, overmolding, and other methods. When filling the first body space 11S with the first filler P1, for example, the main board 4 is buried in the first filler P1 along with the mounted sensor circuit 2 and wireless circuit 3. The connector mounted on the main board 4 may be explosion-proof by not completely burying it in the first filling member P1, but by lengthening the space between the exposed terminals where a potential difference occurs, the surface distance, etc. The main body M1 may also be explosion-proof by combining at least two of the above methods.

[0044] The main body protrusion 12 has a protrusion top surface 121, a protrusion outer periphery 122, and a second main body space 12S (see FIG. 4). The second main body space 12S is an example of a first space.

[0045] As shown in FIG. 3, the convex top surface 121 has a convex top surface 121t that is flush with the end surface (end surface on the other axial side Z2) of the outer circumferential portion 112 opposite the main body facing surface 111a.

[0046] The convex outer periphery 122, together with the main body outer periphery 112, constitutes the outer wall of the main body case 1. The convex outer periphery 122 extends from the convex top surface 121 in a direction perpendicular to the convex top surface 121t (one axial direction side Z1). The convex outer periphery 122 has a first edge 122a facing the main body outer periphery 112, and second and third edge 122c extending from both ends of the first edge 122a toward the main body outer periphery 112. The second edge 122b and third edge 122c are parallel to each other. The first edge 122a has an arc shape with a larger radius of curvature than the main body outer periphery 112 of the main body tubular portion 11 when viewed in the axial direction Z.

[0047] 4, the second body space 12S is a space defined by the convex top surface 121, the convex outer periphery 122, and the body outer periphery 112 of the tubular body portion 11. The second body space 12S is open on the side opposite to the side on which the first body space 11S is open (one axial side Z1).

[0048] 3 and 4, the second body space 12S is separated from the first body space 11S by the outer circumferential body portion 112 of the tubular body portion 11. This prevents the liquid-tight state of the first body space 11S from being disturbed.

[0049] 3, the convex top surface portion 121 is formed with a first screw hole 121h penetrating the convex top surface portion 121 along the axial direction Z, and a bottomed groove portion 121m recessed from the convex top surface 121t along the axial direction Z. The first screw hole 121h communicates with the second main body space 12S described with reference to FIG.

[0050] A screw S for fixing the attachment portion A1 and the main body case 1 to each other is inserted into the first screw hole 121h.

[0051] A protrusion 52t (see FIG. 6) of the battery section B1 (battery case 5, described later) fits into the groove 121m.

[0052] As shown in FIGS. 3 to 5, the sensor circuit 2 has a sensor section 21 (see FIG. 4) and a sensor control section 22 (see FIG. 3).

[0053] 5, when the sensor device 100 is attached to the meter G1, the sensor unit 21 is disposed at a position overlapping the shaft member G17 as viewed in the axial direction Z. The sensor unit 21 is mounted on a surface 41 (hereinafter referred to as the "first surface 41") of the main body substrate 4 that faces the main body bottom surface 111. In this embodiment, the main body substrate 4 is a two-layer substrate consisting of the first surface 41 and a second surface 42 opposite the first surface 41, but may also be a multi-layer substrate having three or more layers. The main body substrate 4 is, for example, a rigid substrate or a flexible substrate.

[0054] The sensor unit 21 includes a magnetic sensor. The magnetic sensor outputs data indicating the direction of the magnetic field and the magnitude of the magnetic force generated by the magnet G18 described with reference to FIG. 2. The magnetic sensor may be one that uses the Hall effect, MR effect, MI effect, or other sensing method. The magnetic sensor is selected based on the distance between the magnetic sensor and the magnet G18 of the meter G1 and the magnetic force of the magnet G18, ensuring its use.

[0055] 3, the sensor control unit 22 is mounted on the second surface 42 of the main body substrate 4. The sensor control unit 22 acquires position information of the magnet G18 (pointer G14) described with reference to FIG. 2 based on the data output from the sensor unit 21, and acquires the measurement value of the gauge G1 based on the position information.

[0056] The radio circuit 3 is mounted on the second surface 42 of the main body board 4. The radio circuit 3 has an antenna 31. Data indicating the acquired measurement values ​​is transmitted via the antenna 31 to an external device (not shown).

[0057] A receptacle R is mounted on the second surface 42 of the main body substrate 4, and is electrically connected to the pattern formed on the main body substrate 4. The receptacle R, together with a plug P that fits into the receptacle R and an electric wire L (see FIG. 6 ) having one end connected to the plug P, constitutes the connection member C provided in the sensor device 100. The other end of the electric wire L is electrically connected to the battery unit B1 (battery substrate 7, described below).

[0058] The main body M1 and the battery B1 are electrically connected when the plug P is fitted into the receptacle R. As a result, electricity is supplied from the battery B1 to the main body M1 (sensor circuit 2 and wireless circuit 3).

[0059] [Battery Unit] The battery unit B1 supplies electricity to the main body unit M1. As shown in FIG. 5 , the battery unit B1 has a battery case 5, a battery 6, a battery board 7, and a lid unit 8. The battery 6 generates electricity to be supplied to the main body unit M1 (sensor unit 21). The battery 6 is composed of, for example, three coin-type batteries. The three coin-type batteries are electrically connected to the battery board 7 via conductive members (terminals). The number of coin-type batteries is not limited to three, and may be two or less, or four or more.

[0060] As shown in Fig. 6 , the battery case 5 has substantially the same outer dimensions and shape as the main case 1 when viewed in the axial direction Z. The battery case 5 houses a battery 6 and a battery substrate 7 (see Fig. 5 ). The battery case 5 is separable from the main case 1 and is located on the side of the main case 1 farther from the transparent plate G15 (the other axial side Z2).

[0061] In this embodiment, the battery case 5 has a battery cylindrical portion 51 and a battery protrusion 52 that protrudes from the outer circumferential surface of the battery cylindrical portion 51 radially outward from the battery cylindrical portion 51 .

[0062] The battery cylindrical portion 51 is cylindrical and includes a battery outer peripheral portion 511 and a battery space 5S. The battery outer peripheral portion 511 is circular when viewed from the axial direction Z.

[0063] The battery space 5S is a space defined by the battery outer periphery 511. The battery space 5S is open at both ends in the axial direction Z (one axial side Z1 and the other axial side Z2). One side of the battery space 5S (one axial side Z1) is connected to the main body case 1 and is covered by the main body case 1, and the other side (the other axial side Z2) is covered by the lid portion 8. Alternatively, the other side of the battery space 5S may be closed by a second filling member P2 described below. The battery case 5 and the lid portion 8 may be integral or separate.

[0064] As shown in FIG. 5 , the battery space 5S accommodates a battery 6 and a battery substrate 7. In this embodiment, the battery space 5S is filled with an insulating second filler P2, similar to the first main body space 11S. This makes the battery section B1 explosion-proof. Methods for making the battery section B1 explosion-proof include filling the battery space 5S with the second filler P2, ensuring an insulating distance in spaces where a potential difference occurs, on component surfaces, applying a resin material such as a potting agent to the target component, or overmolding. The battery section B1 can also be made explosion-proof by combining at least two of the above methods.

[0065] The battery protrusion 52 has a protrusion 52t for engaging with the groove 121m of the main case 1 (see also FIG. 6 ). The protrusion 52t protrudes along the axial direction Z (toward one axial side Z1) from the battery protrusion end surface 52a (the end surface facing the main case 1) of the battery protrusion 52. The main case 1 and the battery case 5 are joined together (the battery case 5 is attached to the main case 1) by fitting the protrusion 52t into the groove 121m described with reference to FIG. 3 .

[0066] 5 and 6, the sensor device 100 further includes a sealing member M such as an O-ring, which is disposed at the boundary between the main body portion M1 (main body case 1) and the battery portion B1 (battery case 5). This allows the battery space 5S and the first main body space 11S (see FIG. 5) to be liquid-tight.

[0067] [Mounting Portion] The mounting portion A1 is made of an insulating material and has an outer size and shape corresponding to the second body space 12S described with reference to FIG.

[0068] More specifically, as shown in FIGS. 7 to 9, the mounting portion A1 has a generally rectangular parallelepiped shape and includes a top surface portion 91, a bottom surface portion 92 (an example of an opposing portion), a side surface portion 93, and a protrusion portion 94.

[0069] 7 and 8, the mounting portion A1 is formed with a second screw hole 9h into which a fastening member such as a screw is fastened. The second screw hole 9h is formed in a position coaxial with the first screw hole 121h formed in the main body protrusion 12 (protrusion top surface 121) described with reference to FIG. 3 when the mounting portion A1 is accommodated in the second main body space 12S.

[0070] 5, at least a portion of the mounting portion A1 (in this embodiment, the entire mounting portion A1 when the protrusion 94 is welded) is accommodated in the second body space 12S. When accommodated in the second body space 12S, the mounting portion A1 does not overlap with the shaft member G17 when viewed in the axial direction Z. As described above, when the sensor device 100 is attached to the meter G1, the sensor unit 21 is positioned so as to overlap with the shaft member G17 when viewed in the axial direction Z. In other words, the mounting portion A1 is positioned so as not to overlap with either the shaft member G17 or the sensor unit 21 in the axial direction Z.

[0071] The mounting portion A1 is accommodated in the second body space 12S so that the top surface 91 is on the side farther from the transparent plate G15 (the other axial side Z2) and the bottom surface 92 is on the side closer to the transparent plate G15 (the one axial side Z1). The bottom surface 92 has an opposing mounting surface 92a that faces (or comes into contact with) the transparent plate G15 when the mounting portion A1 is accommodated in the second body space 12S.

[0072] 7 and 9 , the side surface portion 93 extends from the top surface portion 91 to the bottom surface portion 92. The side surface portion 93 includes two first side surface portions 931 facing each other in the short direction and two second side surface portions 932 facing each other in the long direction.

[0073] As shown in Fig. 8 , one of the first side surface portions 931 has a shape (arc shape) corresponding to the outer circumferential body portion 112 of the tubular main body portion 11 described with reference to Fig. 4 , and the other has a shape (arc shape with a larger radius of curvature than one of the first side surface portions 931) corresponding to the first edge portion 122a of the main body protrusion 12. Hereinafter, one of the first side surface portions 931 will be referred to as the "first inner side surface portion 931a," and the other will be referred to as the "first outer side surface portion 931b." Note that the attachment portion A1 is accommodated in the second main body space 12S so that the first inner side surface portion 931a is closer to the outer circumferential body portion 112 and the first outer side surface portion 931b is farther from the outer circumferential body portion 112 (see Fig. 5 ).

[0074] 5, in a state in which the attachment portion A1 is accommodated in the second body space 12S, the top surface portion 91 contacts the convex top surface portion 121 that defines the second body space 12S, the first outer side surface portion 931b contacts the convex outer periphery portion 122 that defines the second body space 12S, and the first inner side surface portion 931a contacts the main body outer periphery portion 112 of the main body tubular portion 11. In addition, the second side surface portion 932 also contacts the convex outer periphery portion 122 (the second edge portion 122b and the third edge portion 122c shown in FIG. 3) that defines the second body space 12S.

[0075] As shown in FIG. 9 , the protrusion 94 has the bottom surface portion 92 as its base end and protrudes in a direction away from the top surface portion 91 (sensor device main body D1) (toward one axial side Z1). In this embodiment, the protrusion 94 is the portion to be welded (ultrasonic welding in this embodiment) to the transparent plate G15. Welding the protrusion 94 to the transparent plate G15 fixes the mounting portion A1 to the transparent plate G15. When the protrusion 94 is welded to the transparent plate G15, the mounting surface 92a of the bottom surface portion 92 is joined to the transparent plate G15 via the portion where the protrusion 94 is welded (the welded portion). Note that the protrusion 94 may be a single continuous shape or may be a plurality of scattered shapes.

[0076] [Method of Mounting the Sensor Device to the Meter] Next, a method of mounting the sensor device 100 to the meter G1 will be described with reference to FIG.

[0077] After placing (positioning) the mounting portion A1 at a predetermined position on the transparent plate G15 using a special jig, the mounting portion A1 is fixed to the transparent plate G15 by welding the protrusion 94 (see Figures 7 and 9) to the transparent plate G15.

[0078] Thereafter, the main body case 1 (main body portion M1) is arranged so that the attachment portion A1 fixed to the transparent plate G15 is accommodated in the second main body space 12S.

[0079] Then, the screw S is inserted through the first screw hole 121h (see FIG. 3) of the main body case 1 and the second screw hole 9h (see FIG. 7) of the attachment portion A1 from the other axial side Z2 to the one axial side Z1 to fasten the main body case 1 and the attachment portion A1 together. This fixes the attachment portion A1 and the main body case 1 to each other.

[0080] The main body case 1 fixed to the mounting portion A1 may or may not have a battery case 5 attached to it, and if the battery portion B1 is not attached to the main body portion M1, the battery case 5 (battery portion B1) may be attached to the main body case 1 after the main body case 1 (main body portion M1) is fixed to the mounting portion A1.

[0081] This completes the attachment of the sensor device 100 to the transparent plate G15. Then, as shown in FIG. 1 , the transparent plate G15 with the sensor device 100 attached thereto is assembled to the meter G1, thereby completing the attachment of the sensor device 100 to the meter G1. The assembly of the transparent plate G15 with the sensor device 100 attached to the meter G1 may be performed while the meter G1 is attached to the device under test, which is the measurement target of the meter G1, or while the meter G1 is detached from the device under test. The transparent plate G15 may also be assembled to the meter G1 before the battery unit B1 is attached to the main body M1.

[0082] 10 and 11 , the mounting portion A1 may have a flange 921 in which a bottom surface portion 92 protrudes in a direction perpendicular to the axial direction Z beyond the side surface portion 93. The flange 921 has a shape that is slightly larger than (similar to) the bottom surface portion 92 when viewed in the axial direction Z. The protrusion 94 is disposed at the same position and has the same shape as in the first embodiment, and is formed inside the outer edge of the flange 921.

[0083] When the mounting portion A1 is configured as described above, the shape of the main body case 1 (the shape of the main body protrusion 12) is preferably changed according to the shape of the flange 921, as shown in FIG. 11 . Specifically, as shown in FIG. 12 , the end face of the main body protrusion 12 opposite the side where the battery case 5 is attached (one axial side Z1) (hereinafter referred to as the "main body protrusion end face 12t") is set back from the main body-facing surface 111a of the main body bottom portion 111 toward the side where the battery case 5 is attached (the other axial side Z2). That is, a first step d1 is formed in the main body case 1 between the main body-facing surface 111a and the main body protrusion end face 12t. The height H1 of the first step d1 is set equal to (or approximately equal to) the length L1 of the flange 921 in the axial direction Z. Therefore, when the mounting portion A1 is housed in the second main body space 12S, there is no step between the mounting surface 92a of the flange 921 and the main body facing surface 111a, and the mounting surface 92a and the main body facing surface 111a are flat (flush). The mounting surface 92a is the surface of the flange 921 that faces the transparent plate G15 and is the end face opposite to the side where the battery case 5 is attached. As described above, when the protrusion 94 is welded to the transparent plate G15, the mounting surface 92a (including the flange 921 portion) is joined to the transparent plate G15 via the welded portion.

[0084] Second Embodiment Next, a sensor device 100 according to a second embodiment will be described with reference to Figures 13 and 14. In the second embodiment, the shapes of the attachment portion A1 and the main body case 1 are different from those of the first embodiment, and the attachment portion A1 is fitted onto the main body case 1 in the axial direction Z. Note that, in the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description of the same components as those in the first embodiment will be omitted.

[0085] [Main body case] As shown in Figures 13 and 14, the main body case 1 according to this embodiment has a second step d2 formed along the outer wall, and the main body case 1 has an upper-step wall portion 1a above the second step d2 (outside the main body case 1) and a lower-step wall portion 1b (an example of a mating portion) below the second step d2 (inside the main body case 1).

[0086] The stepped upper wall portion 1a constitutes the outermost surface (hereinafter referred to as the "outer surface 1g") of the outer wall of the main body case 1. The stepped upper wall portion 1a is disposed on the side of the main body case 1 to which the battery case 5 is coupled (the other axial side Z2).

[0087] The stepped lower wall portion 1b is disposed on the opposite side (one axial side Z1) of the main body case 1 from the side to which the battery case 5 is coupled. The stepped lower wall portion 1b is configured to be more inward of the main body case 1 than the stepped upper wall portion 1a. The mounting portion A1 is fitted (engaged) onto the stepped lower wall portion 1b.

[0088] In this embodiment, the main body case 1 further has at least one recess 1c (an example of a locking portion) for restricting movement of the fitted attachment portion A1 in the direction along the axial center line Z. The recess 1c is configured by a depression formed in the step-down wall portion 1b on the side of the main body cylindrical portion 11.

[0089] 13 , the main body bottom portion 111 of the main body case 1 further includes a recessed portion 111k that is recessed from the main body-facing surface 111a toward the side where the battery case 5 is coupled (the other axial side Z2). The recessed portion 111k is formed in an annular shape that surrounds the outer periphery of the main body-facing surface 111a when viewed in the axial direction Z. In other words, the main body-facing surface 111a has a circular shape that is slightly smaller than the main body tubular portion 11 when viewed in the axial direction Z.

[0090] [Mounting Portion] The mounting portion A1 is configured to have the same (or substantially the same, the same applies below) outer dimensions and shape as those of the main body case 1 when viewed in the axial direction Z. Specifically, the bottom surface portion 92 of the mounting portion A1 is configured to have the same outer dimensions and shape as those of the step-down wall portion 1b (recessed portion 111k) when viewed in the axial direction Z.

[0091] In this embodiment, the side surface portion 93 (an example of a fitting portion) of the attachment portion A1 is fitted onto the main body case 1 in the axial direction Z. Specifically, the side surface portion 93 is configured to have the same outer dimensions and shape as the stepped upper wall portion 1a when viewed in the axial direction Z. The side surface portion 93 extends along the axial direction Z, with the outer edge of the bottom surface portion 92 as its base end. Therefore, when the attachment portion A1 is fitted onto the stepped lower wall portion 1b of the main body case 1, there is no step between the outer surface of the side surface portion 93 and the outer surface 1g of the main body case 1 in the direction perpendicular to the axial direction Z, and the two surfaces are flat (flush).

[0092] In this embodiment, a fitting hole 92h is formed in the bottom surface portion 92 of the mounting portion A1, penetrating the bottom surface portion 92. As viewed in the axial direction Z, the outer dimensions and outer shape of the fitting hole 92h correspond to the shape (circular) and dimensions of the main body facing surface 111a surrounded by the recessed portion 111k, and the main body facing surface 111a may be fitted into the fitting hole 92h. Note that, as viewed in the axial direction Z, the fitting hole 92h may have a shape larger than that of the main body facing surface 111a. As viewed in the axial direction Z, the center of the fitting hole 92h coincides (including approximately coincidence, the same applies below) with the center of the main body tubular portion 11.

[0093] Furthermore, the attachment portion A1 further has at least one claw portion 95 that is engaged with the recess 1c of the main body case 1.

[0094] The claw portions 95 are configured to be elastically deformable in a direction perpendicular to the axial direction Z. The claw portions 95 utilize their elastic force to fit into the recesses 1c (snap fit). When the claw portions 95 fit into the recesses 1c, movement of the main body case 1 relative to the mounting portion A1 in the axial direction Z is restricted. This prevents the main body case 1 from falling off the mounting portion A1. In this embodiment, as shown in FIG. 14 , three claw portions 95 are provided, and the three claw portions 95 are arranged on the side surface portion 93 that fits into the main body tubular portion 11. The three claw portions 95 are arranged at approximately equal intervals (90-degree intervals around the axis AX) when viewed in the axial direction Z. The positions and number of the recesses 1c of the main body case 1 are provided corresponding to the positions and number of the claw portions 95.

[0095] The mounting portion A1 further includes a cylindrical extension portion 96 that extends from the bottom surface portion 92 along the axial direction Z (in the same direction as the extension direction of the side surface portion 93).

[0096] A third screw hole 96h is formed in the extension portion 96. The third screw hole 96h is formed coaxially with the first screw hole 121h of the case body 1, to which the mounting portion A1 is fitted. A screw S is inserted through the first screw hole 121h (see FIG. 14 ) and the third screw hole 96h of the case body 1 to fasten the case body 1 and the mounting portion A1 together. This more firmly secures the case body 1 to the mounting portion A1. In this case, the claw portion 95 of the mounting portion A1 and the recess 1c of the case body 1 may have a half-lock shape that allows the engagement to be released by pulling without breaking. Furthermore, when the mounting portion A1 is fitted to the case body 1, the end surface of the extension portion 96 opposite the bottom surface portion 92 may contact the convex top surface portion 121 that defines the second body space 12S (see FIG. 13 ).

[0097] [Method of Attaching the Sensor Device to the Meter] In the method of attaching the sensor device 100 to the meter G1 according to the second embodiment, the attachment portion A1 is welded to the attachment portion A15, as in the first embodiment. Then, the main body case 1 is attached to the attachment portion A1, but the method of fastening the attachment portion A1 to the main body case 1 (main body portion M1) differs from that of the first embodiment. Specifically, in the method according to the second embodiment, the main body case 1 is internally fitted to the attachment portion A1, i.e., the attachment portion A1 is externally fitted to the main body case 1, and the claw portion 95 of the attachment portion A1 is engaged with the recess 1c of the main body case 1, thereby fastening the main body case 1 to the attachment portion A1. Furthermore, if necessary, screws S are inserted through the first screw hole 121h (see FIG. 14) and the third screw hole 96h of the main body case 1 to fasten the main body case 1 and the attachment portion A1 together.

[0098] [Modification of the Second Embodiment] As shown in FIG. 15 , the mounting portion A1 may have a flange 921 in which the bottom surface 92 protrudes further outward from the mounting portion A1 than the protrusion 94. The flange 921 extends further outward than the main body case 1 fixed to the mounting portion A1 when viewed in the axial direction Z. It is preferable that the flange 921 be larger than the main body case 1 by, for example, 1 mm to 5 mm when viewed in the axial direction Z. It is also preferable that the flange 921 does not overlap the scale G161 on the scale plate G16 when viewed in the axial direction Z. As a modification of the second embodiment, the flange 921 may be omitted, and the protrusion 94 may be formed at a position more inward of the mounting portion A1 than the mounting portion A1 according to the second embodiment.

[0099] 16 and 17, a sensor device 100 according to a third embodiment will be described. The third embodiment differs from the first and second embodiments in that the attachment portion A1 is integrally formed with the main body case 1. In the following description, the same components as those in the first and second embodiments will be denoted by the same reference numerals, and detailed description of the same components as those in the first and second embodiments will be omitted.

[0100] 16 and 17, in this embodiment, the shape of the main body protrusion 12 of the main body case 1 is different from that of the first and second embodiments. Specifically, the main body protrusion 12 does not have the second main body space 12S that accommodates the attachment portion A1, and further has two recessed portions 12k.

[0101] The recessed portion 12k is formed by a recessed portion of the main body protrusion 12. Specifically, the recessed portion 12k is formed by a portion recessed along the axial direction Z from the protrusion-facing surface 12a of the main body protrusion 12 toward the side where the battery case 5 is coupled (the other axial direction side Z2). The protrusion-facing surface 12a is the surface of the main body protrusion 12 that faces the transparent plate G15 when the sensor device 100 is attached to the transparent plate G15, and is flush with the main body-facing surface 111a of the main body bottom portion 111.

[0102] The two recesses 12k face each other across the protrusion-facing surface 12a. Two mounting shafts 97 are disposed in each of the two recesses 12k. The two mounting shafts 97 are integrally formed with the main body case 1. The two mounting shafts 97 are disposed at positions that do not overlap with the sensor unit 21 (see FIG. 4) when viewed from the axial direction Z. In this embodiment, the two mounting shafts 97 constitute (are included in) the mounting portion A1.

[0103] [Mounting shaft] Each of the two mounting shafts 97 extends from the bottom wall (the wall on which the battery case 5 is disposed) of each of the two recesses 12k along the axial direction Z (toward one axial side Z1). The mounting shaft 97 protrudes in the axial direction Z beyond the convex portion facing surface 12a (main body bottom surface portion 111).

[0104] The mounting shaft 97 includes two split pieces 971 split along the axial direction Z, and the two split pieces 971 are elastically deformable in a direction moving toward or away from each other (a direction perpendicular to the axial direction Z). The split pieces 971 have protruding pieces 972 at their tips that protrude in a direction moving away from the tips of the opposing split pieces 971. It is sufficient that the protruding piece 972 is formed on at least one of the split pieces 971.

[0105] Each of the mounting shafts 97 utilizes its elastic force to fit (snap fit) into each of the two mounting holes 151h formed in the transparent plate G15.

[0106] Each of the two mounting holes 151h is formed to penetrate the transparent plate G15 along the axial direction Z. Note that, as viewed in the axial direction Z, the shape of the mounting hole 151h is such that the protruding piece 972 can pass through when the segment 971 of the mounting shaft 97 is elastically deformed as viewed in the axial direction Z, but the protruding piece 972 cannot pass through when the elastic deformation of the segment 971 is restored after the protruding piece 972 has passed, for example, a rectangle.

[0107] When the mounting shaft 97 is fitted into the mounting hole 151h, the protruding piece 972 of the divided piece 971 comes into contact with the surface of the transparent plate G15 facing the scale plate G16 (the surface on one side Z1 in the axial direction).

[0108] 17 , in this embodiment, the mounting portion A1 includes one support shaft 98 in addition to the two mounting shafts 97. The support shaft 98 is configured integrally with the main body case 1. The support shaft 98 is disposed on the main body-facing surface 111 a of the main body case 1 (the end surface on one axial side Z1 of the main body tubular portion 11) and extends from the main body-facing surface 111 a along the axial direction Z in the direction in which the mounting shaft 97 extends (one axial side Z1). The support shaft 98 is also disposed in a position that does not overlap with the sensor unit 21 (see FIG. 4 ) when viewed in the axial direction Z.

[0109] The support shaft 98 is fitted into a support hole 152h formed in the transparent plate G15. The support hole 152h is formed to penetrate the transparent plate G15 along the axial direction Z. When viewed from the axial direction Z, the shape of the support hole 152h corresponds to the shape of the support shaft 98, and is, for example, circular, and it is preferable that the gap between the support hole 152h and the support shaft 98 is small.

[0110] [Method of Mounting Sensor Device to Meter] In the method of mounting the sensor device 100 to the meter G1 according to the third embodiment, the method of mounting the main case 1 to the transparent plate G15 differs from the first and second embodiments. Specifically, in the method according to the third embodiment, the support shaft 98 is fitted into the support hole 152h, and the two mounting shafts 97 are elastically deformed toward each other and inserted into the mounting holes 151h of the transparent plate G15, respectively, and then returned to their original state (separated). As a result, the protruding piece 972 of the split piece 971 contacts the transparent plate G15 (the surface on one side Z1 of the transparent plate G15 in the axial direction Z), completing the mounting of the main case 1 (main body portion M1) to the transparent plate G15.

[0111] Effects of the embodiment The sensor device 100 configured as above provides the following effects.

[0112] According to the first to third embodiments, the mounting portion A1 does not overlap with the sensor unit 21 when viewed in the axial direction Z, so the mounting portion A1 is not interposed between the sensor unit 21 and the magnet G18. This allows the sensor unit 21 to be brought closer to the magnet G18. This also reduces variations in the distance between the sensor unit 21 and the magnet G18 due to variations in the dimensional accuracy and / or mounting state of the mounting portion A1. This therefore prevents a decrease in the accuracy of the sensor unit 21.

[0113] According to the first and second embodiments, the mounting portion A1 is fixed to the transparent plate G15 by welding the protrusion 94, eliminating the need to use separate materials such as double-sided tape or adhesive to attach the sensor device main body D1 to the instrument G1. For example, even if double-sided tape of the same specifications were used, the force of the sensor device main body D1 pressing against the transparent plate G15 could cause the double-sided tape to elastically deform, changing the distance between the sensor unit 21 and the magnet G18 and potentially reducing the accuracy of the sensor device 100. However, according to the first and second embodiments, double-sided tape is not required to attach the sensor device main body D1 to the instrument G1. This prevents the distance between the sensor unit 21 and the magnet G18 from changing. As a result, the accuracy of the sensor device 100 is prevented from decreasing.

[0114] Furthermore, the sensor device 100 is not limited to being attached vertically above the device under test together with the transparent plate G15 (meter G1), but may be attached in various directions relative to the device under test. Therefore, when the sensor device 100 is attached to the meter G1 using double-sided tape, the weight of the sensor device 100 constantly acts on the surface to which the double-sided tape is attached, potentially causing the sensor device 100 to fall off the transparent cover. However, according to the first and second embodiments, the sensor device 100 is attached to the transparent plate G15 by fastening the main body case 1 (by press-fitting or external fitting, and then fastening with screws S) to the mounting portion A1 fixed to the transparent plate G15 by welding. Therefore, there is no need to use double-sided tape to attach the sensor device 100 to the meter G1, and the sensor device 100 can be prevented from falling off the meter G1.

[0115] Another method is to attach the sensor device main body D1 to the transparent plate G15 using adhesive instead of double-sided tape, but this method requires time for the adhesive to harden. Furthermore, the adhesive may spread across the surface of the transparent plate G15, impairing the visibility of the scale G161 indicated by the pointer G14. Furthermore, the adhesive may spread to a position overlapping the sensor unit 21 when viewed from the axial direction Z, causing a change in the distance between the sensor unit 21 and the magnet G18, potentially reducing the detection accuracy of the sensor device 100. However, according to the above embodiment, there is no need to use adhesive.

[0116] Furthermore, because the change in the distance between the sensor unit 21 and the magnet G18 can be suppressed as described above, when the sensor unit 21 is a magnetic sensor IC as in the first and second embodiments, the correction value for correcting the measurement value of the meter G1 acquired by the magnetic sensor IC can be shared with other sensor devices included in the inspection system. The other sensor devices are meters of the same type as the meter G1 (meters whose transparent plate has the same thickness as the transparent plate G15 (including meters whose transparent plate has a thickness that is approximately the same; the same applies below)) and whose magnetic sensor IC and magnet have the same distance between the sensor unit 21 of the sensor device 100 and the magnet G18 of the meter G1. In other words, according to this embodiment, the distance between the magnetic sensor ICs of the multiple sensor devices in the inspection system and the magnets whose magnetic field direction and magnitude the magnetic sensor ICs detect can be equalized, and the correction value (the value for correcting the data acquired by the magnetic sensor IC) can be shared among the multiple sensor devices. This eliminates the need to acquire correction values ​​for each sensor device, thereby improving the efficiency of the measurement value acquisition process.

[0117] As described in the first and second embodiments, the protrusion 94 to be welded to the transparent plate G15 protrudes from the bottom surface 92 of the mounting portion A1, which is separate from the main case 1, toward the transparent plate G15. Therefore, ultrasonic welding (hereinafter referred to as "ultrasonic welding") can be used as a method for welding the protrusion 94. With ultrasonic welding, the strength of the attachment of the mounting portion A1 to the transparent plate G15 can be determined by the material properties of the mounting portion A1 and the transparent plate G15, the shape of the protrusion 94, and the various conditions of the ultrasonic welding device (frequency, welding time, horn shape, etc.). Therefore, by adjusting the shape of the protrusion 94 and the various conditions of the ultrasonic welding device according to the material properties of the mounting portion A1 and the transparent plate G15, it is possible to attach the mounting portion A1 to the transparent plate G15 to achieve the desired strength. Furthermore, adjusting the various conditions can also shorten the time required to attach the mounting portion A1 to the transparent plate G15.

[0118] In addition, in the method of forming a welding portion to be welded in the main case 1 and then fixing the main case 1 to the transparent plate G15 by ultrasonic welding to the welding portion, there is a risk that the application of ultrasonic waves will damage at least one of the sensor circuit 2 and the wireless circuit 3 housed in the main case 1. Alternatively, there is a risk that cracks will occur in at least one of the first filling member P1 filled in the first body space 11S of the main case 1 and the second filling member P2 filled in the battery space 5S, which will reduce the explosion-proof performance, waterproof performance, etc. of the sensor device 100. However, in the first and second embodiments, the protrusion 94 of the mounting portion A1, which is separate from the main case 1, is ultrasonically welded rather than the main case 1, and then the main case 1 is fixed to the mounting portion A1. This makes it possible to prevent damage to at least one of the sensor circuit 2 and the wireless circuit 3 housed in the main case 1, or a deterioration in the explosion-proof performance, waterproof properties, etc. of the sensor device 100 due to cracks in at least one of the first filling member P1 filled in the main case 1 and the second filling member P2 filled in the battery case 5.

[0119] According to the first embodiment, the attachment part A1, which is separate from the main body case 1, is housed in the main body case 1 (the second main body space 12S). That is, since the attachment part A1 is disposed inside the main body case 1, it is possible to avoid an increase in the size of the sensor device 100.

[0120] Furthermore, according to the first embodiment, when the mounting portion A1 is housed in the second body space 12S, the top surface portion 91 contacts the convex top surface portion 121 that defines the second body space 12S, the first outer side surface portion 931b contacts the convex outer peripheral portion 122 that defines the second body space 12S, the first inner side surface portion 931a contacts the main body outer peripheral portion 112 of the main body tubular portion 11, and the second side surface portion 932 also contacts the convex outer peripheral portion 122 that defines the second body space 12S. Therefore, movement of the main body case 1 relative to the mounting portion A1 can be restricted in a direction perpendicular to the axial direction Z (including a direction substantially perpendicular thereto; the same applies below). Furthermore, because the top surface portion 91 of the mounting portion A1 contacts the convex top surface portion 121 that defines the second body space 12S, movement of the main body case 1 in a direction away from the mounting portion A1 can also be restricted.

[0121] Furthermore, in the first embodiment, the mounting portion A1 and the main body case 1 are fastened together with the screw S, which restricts movement of the main body case 1 in the axial direction Z relative to the mounting portion A1. In this case, it is not necessary for all of the top surface portion 91, the first outer side surface portion 931b, the first inner side surface portion 931a, and the second side surface portion 932 of the mounting portion A1 to contact the wall defining the second body space 12S. Note that the method for fastening the main body case 1 and the mounting portion A1 is not limited to the method using the screw S. For example, the main body case 1 and the mounting portion A1 may be fastened by press-fitting the mounting portion A1 into the second body space 12S, or the main body case 1 and the mounting portion A1 may be fastened by a structure in which the main body case 1 and the mounting portion A1 engage in a direction that prevents the main body case 1 and the mounting portion A1 from separating (a direction in which they approach each other).

[0122] According to the first embodiment, the second body space 12S is separated from the first body space 11S, which prevents water, dust, and the like from entering the first body space 11S through the second body space 12S. This prevents the liquid-tight state of the first body space 11S from being disturbed. Note that the first screw hole 121h described in the first embodiment is preferably positioned outside the main body case 1 relative to the sealing member M, such as an O-ring. This further effectively prevents water, dust, and the like from entering the first body space 11S.

[0123] According to the second embodiment, the attachment portion A1 fits onto the outside of the main body case 1, and therefore the main body case 1 can be fixed to the attachment portion A1 without being hidden by the step-down wall portion 1b of the main body case 1. This improves the efficiency of the work of attaching the main body case 1 to the attachment portion A1.

[0124] Furthermore, according to the second embodiment, the attachment portion A1 is fitted onto the outside of the main body case 1, so that movement of the main body case 1 relative to the attachment portion A1 in a direction perpendicular to the axial direction Z is restricted.

[0125] Furthermore, according to the second embodiment, when the fitting hole 92h of the mounting portion A1 is shaped so that the main body facing surface 111a fits into the fitting hole 92h, movement in a direction perpendicular to the axial direction Z of the main body case 1 relative to the mounting portion A1 is restricted.

[0126] Furthermore, in the second embodiment, when the sensor device 100 is attached to the transparent plate G15, the body-facing surface 111a of the main body tubular portion 11, which houses the sensor unit 21, contacts the transparent plate G15 through the fitting hole 92h. Therefore, compared to a configuration in which the fitting hole 92h is not provided, the area of ​​the main body case 1 that contacts the transparent plate G15 can be increased. As a result, the sensor device 100 can be attached to the transparent plate G15 more stably. Furthermore, the sensor unit 21 and the magnet G18 can be arranged closer to each other, which can prevent a decrease in the accuracy of the sensor unit 21.

[0127] In the second embodiment, the fitting hole 92h of the mounting portion A1 is configured to fit into the main body facing surface 111a, and the center of the fitting hole 92h can be aligned with the center of the main body tubular portion 11 when viewed in the axial direction Z. This makes it easy to position the main body case 1 (sensor device main body D1) relative to the mounting portion A1, and the sensor portion 21 can be easily disposed in a desired position relative to the meter G1.

[0128] According to the third embodiment, the mounting portion A1 is integrally formed with the main body case 1, so that the sensor device 100 can be easily mounted to the transparent plate G15 without using a separate mounting portion A1. Furthermore, the main body case 1 can be mounted (fixed) to the transparent plate G15 simply by pressing the main body case 1 against the transparent plate G15. Therefore, even if the main body case 1 has the battery portion B1 mounted thereon, for example, it can be easily fixed to the transparent plate G15.

[0129] Furthermore, according to the third embodiment, there is no need to use welding to attach the main body case 1 to the transparent plate G15, so the main body case 1 can be easily attached to the transparent plate G15.

[0130] Furthermore, according to the third embodiment, when the main body case 1 is attached to the transparent plate G15, the main body-facing surface 111a of the main body tubular portion 11 that houses the sensor unit 21 comes into more reliable contact with the transparent plate G15. As a result, the sensor device 100 can be more stably attached to the transparent plate G15. Furthermore, the sensor unit 21 and the magnet G18 can be disposed closer to each other, which can prevent a decrease in the sensitivity of the sensor unit 21.

[0131] According to the first to third embodiments, the battery case 5 that houses the battery 6 is separable from the main body case 1 and is positioned on the side of the main body case 1 that is far from the transparent plate G15. Therefore, the battery 6 housed in the battery case 5 can be replaced while the main body case 1 remains attached to the transparent plate G15. For example, in a factory that uses the sensor device 100, by keeping only the battery 6 (or the battery unit B1) on hand as a maintenance part and incorporating battery 6 replacement as part of the maintenance work, it is possible to avoid long periods of downtime. In the first to third embodiments, the main body unit M1 and the battery unit B1 are each explosion-proof, so the battery 6 can also be replaced within an explosion-proof area.

[0132] According to the first to third embodiments, by using a general-purpose magnetic sensor as the sensor unit 21, it is possible to easily realize a sensor device 100 that acquires the measurement value of the gauge G1 without contacting the pointer G14.

[0133] As described in the modified examples of the first and second embodiments, the flange 921 in the mounting portion A1 increases the area of ​​the joint with the transparent plate G15. In particular, in the modified example of the first embodiment, the projected area (joining area) along the axial direction Z of the portion of the mounting portion A1 facing the transparent plate G15 (the flange 921) is larger than the projected area along the axial direction Z of the portion of the mounting portion A1 housed in the second body space 12S (the portion other than the flange 921). This improves the fixing strength of the mounting portion A1 to the transparent plate G15 (the attachment strength of the sensor device 100 to the transparent plate G15). Furthermore, it is possible to avoid an increase in the size of the sensor device 100 (the main body case 1) in order to improve the attachment strength. As a result, it is also possible to prevent impairment of the visibility of the pointer G14. Alternatively, it is possible to avoid thinning the outer wall of the main body tubular portion 11 in order to improve the attachment strength while avoiding an increase in the size of the sensor device 100, thereby avoiding a decrease in flame retardancy. Furthermore, since the mounting portion A1 has the flange portion 921, the trace of welding of the protrusion portion 94 is difficult to see from the outside of the sensor device 100, and the aesthetic appearance of the sensor device 100 can be prevented from being impaired.

[0134] Other Embodiments (a) In the first and second embodiments, the attachment portion A1 and the main body case 1 are fastened together by the screw S, but the attachment portion A1 and the main body case 1 do not have to be fastened together. In this case, in the first embodiment, it is preferable that the attachment portion A1 be press-fitted into the second main body space 12S of the main body case 1.

[0135] (b) In the first embodiment, the first body space 11S is filled with the first filling member P1, but the first body space 11S does not have to be filled with the first filling member P1. Similarly, the second body space 12S does not have to be filled with the second filling member P2.

[0136] (c) The main body case 1 described in the second embodiment may omit the step-down wall portion 1b formed so as to be located inside (one step inside) the outer surface 1g of the main body case 1. In this case, the outer surface 1g of the main body case 1 to which the attachment portion A1 is fitted and the outer surface of the attachment portion A1 are not flat, and the outer surface of the attachment portion A1 is located outside the outer surface 1g of the main body case 1.

[0137] (d) The attachment portion A1 described in the second embodiment has the extension portion 96, but the attachment portion A1 may not have the extension portion 96.

[0138] (e) Gaskets or other sealing members may be placed in the gaps between the two mounting shafts 97 and the mounting holes 151h described in the third embodiment, and in the gaps between the support shaft 98 and the support hole 152h. This allows the meter G1 to be kept liquid-tight.

[0139] (f) The support shaft 98 described in the third embodiment may be press-fitted into the support hole 152h, thereby preventing the main case 1 from rattling relative to the transparent plate G15.

[0140] (g) The number of each of the mounting shafts 97 and support shafts 98 described in the third embodiment is not particularly limited as long as the main case 1 can be stably attached to the transparent plate G15. The number of mounting shafts 97 may be one or three or more, and the number of support shafts 98 may be omitted or two or more. In this case, the number of each of the recesses 12k, mounting holes 151h, and support holes 152h is also changed depending on the number of mounting shafts 97 and support shafts 98.

[0141] (h) The sensor unit 21 may output data indicating only the magnitude of the magnetic force (for example, magnetic flux density).

[0142] The present disclosure is applicable to a sensor device.

[0143] DESCRIPTION OF SYMBOLS 1: Main body case 1b: Lower step wall portion (fitted portion) 5: Battery case 6: Battery 11S: First main body space (second space) 12S: Second main body space (first space) 21: Sensor portion 92: Bottom surface portion (opposing portion) 93: Side surface portion (fitting portion) 94: Protrusion portion 97: Mounting shaft 100: Sensor device 111: Main body bottom surface portion (main body facing portion) 151h: Mounting hole (through hole) A1: Mounting portion AX: Axis center D1: Sensor device main body G1: Meter G14: Pointer G15: Transparent plate G16: Scale plate G16a: Scale surface G161: Scale G17: Axis member G18: Magnet Z: Axial center direction

Claims

1. A sensor device for obtaining measurement values ​​of an instrument having a magnet that rotates together with a pointer around the axis of an axis member that is perpendicular to the scale surface on which the scale plate is graduated, and a transparent plate that covers the scale plate, the pointer, and the magnet, comprising: a sensor device main body that is arranged to overlap with the axis when viewed in the axial direction along the axis, has a sensor unit that obtains position information of the magnet and obtains the measurement values ​​based on the position information; and an attachment part for attaching the sensor device main body to the instrument, wherein the attachment part is fixed to the transparent plate so as not to overlap with the sensor unit when viewed in the axial direction.

2. The sensor device described in claim 1, wherein the mounting portion has an opposing portion facing the transparent plate, and a protruding portion having the opposing portion as a base end and protruding in a direction away from the sensor device main body along the axial direction along the axis, and the mounting portion is fixed to the transparent plate by welding the protruding portion to the transparent plate.

3. The sensor device according to claim 1, wherein the sensor device main body further has a main body case that houses the sensor portion, the main body case includes a first space that is open on one side in the axial direction along the axis, and the mounting portion is configured separately from the main body case and at least a portion of the mounting portion is housed in the first space.

4. The sensor device according to claim 3, wherein the main body case further includes a second space for accommodating the sensor unit, and the first space and the second space are separated from each other.

5. A sensor device as described in claim 1 or 2, wherein the sensor device main body further has a main body case that houses the sensor portion, the mounting portion is configured separately from the main body case, and further has an engagement portion that fits externally onto the main body case in the axial direction along the axis, and the main body case includes a fitted portion that fits into the engagement portion.

6. The sensor device as described in claim 1, wherein the sensor device main body includes a main body facing portion that faces the transparent plate and further has a main body case that houses the sensor portion, the mounting portion is integral with the main body case and includes a mounting shaft that protrudes beyond the main body facing portion, and the mounting shaft fits into a through hole that passes through the transparent plate, thereby fixing the main body case to the transparent plate.

7. A sensor device as described in claim 3 or 4, wherein the sensor device main body further has a battery case that contains a battery that generates electricity to be supplied to the sensor section, the battery case being separable from the main body case and positioned on the side of the main body case farther from the transparent plate.

8. The sensor device according to claim 1 or 2, wherein the sensor unit includes a magnetic sensor.

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