Sensor Module

Abstract

To provide a sensor module in which a metal member is usable as a radiation element.SOLUTION: A sensor module includes: a metal member having a side surface extending annularly, and a concave portion recessed from the side surface and annularly provided over the side surface; a resin portion embedded inside the concave portion; a radiation section provided inside the resin portion and for radiating radio waves; a wireless communication section provided inside the resin portion and connected to the radiation section; and a sensor connected to the wireless communication section. The metal member is insulated from the radiation section by the resin portion, and functions as a parasitic element.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a sensor module. [Background technology]

[0002] Conventionally, there has been a rolling bearing device having an inner ring, an outer ring, and a number of rolling elements arranged between the inner ring and the outer ring so as to be freely rotatable relative to one another, the rolling bearing device having a sealing device formed in a circular ring shape, a base end of which is attached to the inner ring or the outer ring and a tip end of which is arranged in a seal groove formed in the outer ring or the inner ring, and a wireless tag is arranged on at least the outer surface of the sealing device.

[0003] It is also described that a temperature sensor, a vibration sensor, etc. may be built into the wireless tag so that temperature information and vibration information can be monitored, and that the rotation signal generated by the speed sensor is provided to a control circuit via a lead wire, etc., but there is no specific description of how the detection data is extracted outside the bearing device.

[0004] In addition, to improve communication conditions, the wireless tag is placed away from metal components, and if a speed sensor is provided, the wireless tag and the speed sensor are attached to a plastic end cap (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2005-042895 A Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional bearing devices, in order to improve communication conditions, the wireless tag is located away from the metal members, and the metal members are not used for communication.

[0007] Therefore, an object of the present invention is to provide a sensor module in which a metal member can be used as a radiating element. [Means for solving the problem]

[0008] A sensor module according to an embodiment of the present invention includes a metal member having a side extending in a ring shape and a recess recessed from the side shape and arranged in a ring shape around the side shape, a resin part embedded in the recess, a radiating part provided inside the resin part and emitting radio waves, a wireless communication part provided inside the resin part and connected to the radiating part, and a sensor connected to the wireless communication part, wherein the metal member is insulated from the radiating part by the resin part and functions as a parasitic element. Effect of the Invention

[0009] It is possible to provide a sensor module in which a metal member can be used as a radiating element. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing a sensor module 100 according to an embodiment. [Diagram 2] FIG. 1 is a side view showing a sensor module 100 according to an embodiment. [Diagram 3] FIG. 2 is a cross-sectional view taken along the line AA in FIG. [Figure 4] 1 is a diagram showing a metal member 110, a multi-module 130, and a power cable 140. FIG. [Diagram 5] FIG. 2 is a top view showing the sensor module 100. [Figure 6] 1 is a block diagram showing a configuration of a sensor module 100. FIG. [Figure 7] 13 is a diagram showing frequency characteristics of the S11 parameter of the sensor module 100. FIG. [Figure 8] 11 is a diagram showing a simulation result of the directivity of the sensor module 100. FIG. [Figure 9]FIG. 11 is a diagram showing a metal member 110M1 according to a first modified example of the embodiment. [Figure 10] FIG. 13 is a diagram showing a sensor module 100M2 according to a second modified example of the embodiment. [Figure 11] FIG. 13 is a block diagram showing a configuration of a sensor module 100M3 according to a third modified example of the embodiment. [Figure 12] FIG. 13 is a diagram showing a sensor module 100M4 of a fourth modified example. [Figure 13] FIG. 13 is a diagram showing a sensor module 100M5 of a fifth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment to which a sensor module of the present invention is applied will be described.

[0012] <Embodiment Mode> Fig. 1 is a perspective view showing a sensor module 100 according to an embodiment. Fig. 2 is a side view showing the sensor module 100 according to an embodiment. Fig. 3 is a diagram showing a cross section taken along the line AA in Fig. 1. In the following description, an XYZ coordinate system is defined, and the XY plane view is referred to as a planar view. For convenience of explanation, the -Z direction side is referred to as the lower side or bottom, and the +Z direction side is referred to as the upper side or top, but this does not represent a universal vertical relationship.

[0013] <Configuration of sensor module 100> The sensor module 100 includes a metal member 110, a resin part 120, a multi-module 130, and a power cable 140. The sensor module 100 is a disk-shaped member. The following description will be given with reference to Figs. 4 and 5 in addition to Figs. 1 to 3. Fig. 4 is a diagram showing the metal member 110, the multi-module 130, and the power cable 140. Fig. 5 is a top view showing the sensor module 100. Fig. 5 shows the arrangement of the multi-module 130 in the sensor module 100.

[0014] As an example, the metal member 110 is a disk-shaped member made of metal, and has an upper surface 111A, a lower surface 111B, a side surface 111C, a slit 111D, a recess 112, and a through hole 113. The upper surface 111A, the lower surface 111B, and the side surface 111C are the upper surface, the lower surface, and the side surface of the disk-shaped member made of metal. The side surface 111C goes around the outer periphery of the metal member 110 and extends in a ring shape.

[0015] The opening of the through hole 113 is located at the center of the upper surface 111A and the lower surface 111B. Therefore, the upper surface 111A and the lower surface 111B are annular in plan view, and the metal member 110 is also annular in plan view. Such a metal member 110 is made of a metal such as stainless steel, iron, aluminum, or tungsten, for example.

[0016] Slit 111D extends in a circular shape around side surface 111C between the upper and lower ends of side surface 111C. The upper end of side surface 111C is the boundary between side surface 111C and upper surface 111A, and the lower end of side surface 111C is the boundary between side surface 111C and lower surface 111B.

[0017] The slit 111D includes inner walls 112A and 112B of the recess 112, in addition to the boundary between the side surface 111C and the recess 112. The inner walls 112A and 112B of the recess 112 are annular inner wall portions parallel to the XY plane of the recess 112. The inner walls 112A and 112B face each other across the internal space of the recess 112.

[0018] Radio waves radiated from antenna element 132 of multi-module 130 propagate through slit 111D, causing resonance of the propagated radio waves. The radio waves resonating in slit 111D are radiated to the outside of metal member 110. In this way, metal member 110 functions as a parasitic element. A parasitic element is synonymous with a parasitic element.

[0019] The recess 112 is provided in an annular shape from between the upper and lower ends of the side surface 111C toward the inside in the radial direction of the metal member 110 around the recessed side surface 111C. The recess 112 has inner walls 112A and 112B and a bottom 112C. The inner walls 112A and 112B are annular inner wall portions parallel to the XY plane and communicate with the bottom 112C. The bottom 112C is located at the innermost part of the recess 112 and is a cylindrical wall portion connecting the inner walls 112A and 112B.

[0020] The bottom 112C is a cylindrical wall portion located outside the through hole 113 and surrounding the radially outer side of the through hole 113. The radial depth from the side surface 111C of the recess 112 to the surface of the bottom 112C is constant around the circumference. The resin portion 120 and the multi-module 130 are housed inside the recess 112.

[0021] Through hole 113 is provided in the center of metal member 110 in plan view, and penetrates metal member 110 so as to connect upper surface 111A and lower surface 111B. Through hole 113 is located inside recess 112 in plan view.

[0022] The resin portion 120 is provided inside the recess 112 of the metal member 110, and is embedded so as to cover the multi-module 130. The resin portion 120 covers the upper surface side of the multi-module 130, and may cover the lower surface side in addition to the upper surface side of the multi-module 130. The resin portion 120 may be any resin that can be filled into the recess 112, and may be, for example, an epoxy resin, an acrylic resin, or the like. The resin portion 120 is used as a sealing resin.

[0023] The multi-module 130 is a module having multiple functions, and includes, as an example, a wiring board 131, an antenna element 132, a matching circuit 132A, a ground layer 133, a wireless communication unit 134, a control unit 135, and a sensor 136. Such a multi-module is an example of an electronic device in which electronic components such as the matching circuit 132A, the wireless communication unit 134, the control unit 135, and the sensor 136 are mounted on the wiring board 131. A power cable 140 for receiving power from an external source is connected to the multi-module 130.

[0024] The upper surface of the multi-module 130 is covered with a resin part 120. This is to separate and insulate the antenna element 132 from the inner wall 112A, and to protect the matching circuit 132A, the ground layer 133, the wireless communication unit 134, the control unit 135, and the sensor 136. In addition, by providing the resin part 120 between the lower surface of the multi-module 130 and the inner wall 112B, the lower surface of the multi-module 130 may also be covered with the resin part 120.

[0025] As an example, wiring board 131 is a wiring board conforming to FR-4 (Flame Retardant type 4) standard. Wiring board 131 is annular in plan view to avoid through-hole 113, and has opening 131A at the center in plan view. The opening diameter of opening 131A is slightly larger than the diameter of bottom 112C located at the innermost side of recess 112 of metal member 110, and opening 131A positions wiring board 131 relative to bottom 112C. Wiring board 131 may be a flexible board realized by a polyimide film or the like. Wiring board 131 is arranged parallel to the XY plane.

[0026] Antenna element 132, matching circuit 132A, wireless communication unit 134, control unit 135, and sensor 136 are mounted on the upper surface of wiring board 131, and a ground layer 133 is provided on a part of the lower surface. Ground layer 133 is provided in a portion that overlaps with antenna element 132, matching circuit 132A, wireless communication unit 134, control unit 135, and sensor 136 in plan view.

[0027] The antenna element 132 is an example of a radiating portion, and is realized by a metal layer provided on the upper surface of the wiring board 131. The antenna element 132 is provided near the inner walls 112A and 112B of the slit 111D. Near means that the antenna element 132 and the slit 111D are close enough that electromagnetic field coupling occurs between the antenna element 132 and the slit 111D. The antenna element 132 is covered with the resin part 120, and is therefore separated from the metal member 110 and insulated from the metal member 110.

[0028] The antenna element 132 has a linear pattern and extends in the extending direction of the annular recess 112. "Along the extending direction of the annular recess 112" means along the circumferential direction of the recess 112, and the longitudinal direction of the linear antenna element 132 extends along the circumferential direction. The shape of the antenna element 132 in a plan view is not limited to a linear shape, and may be various shapes such as an inverted F shape, an inverted L shape, or a circle.

[0029] As an example, the antenna element 132 is formed by patterning copper foil. The antenna element 132 forms a microstrip line together with the ground layer 133. The antenna element 132 is a microstrip line type radiating element. The antenna element 132 is connected to the wireless communication unit 134 via the wiring of the wiring board 131, and the portion to which the wiring of the wiring board 131 is connected is the power supply unit 132FP.

[0030] The antenna element 132 is fed with power from the wireless communication unit 134 and radiates radio waves into the recess 112. The wiring connecting the antenna element 132 and the wireless communication unit 134 also forms a microstrip line with the ground layer 133. A matching circuit 132A for impedance matching is connected near the power feed unit 132FP of the antenna element 132. As an example, the matching circuit 132A is an inductor or a capacitor. By using the matching circuit 132A, a wavelength shortening effect can be obtained.

[0031] As described above, the ground layer 133 is provided on the lower surface or an inner layer of the wiring board 131 so as to overlap with the antenna element 132, the matching circuit 132A, the wireless communication unit 134, the control unit 135, and the sensor 136 in a plan view. The ground layer 133 is realized by a metal layer provided on the lower surface or an inner layer of the wiring board 131, and the metal layer is, for example, a copper foil. The ground layer 133 is connected to the metal member 110.

[0032] When the ground layer 133 is on the lower surface of the wiring board 131, the ground layer 133 and the inner wall 112B of the recess 112 may be in direct contact with each other. In this case, the resin part 120 may not be present between the multi-module 130 and the inner wall 112B. When the ground layer 133 is on the lower surface of the wiring board 131, the ground layer 133 and the inner wall 112B of the recess 112 may be connected with a conductive adhesive, wiring, or the like. In this case, the resin part 120 may or may not be present between the multi-module 130 and the inner wall 112B. The ground layer 133 may be provided on the inner layer of the wiring board 131. In this case, the ground layer 133 and the metal member 110 may be connected with wiring, pads, or the like. In this case, the resin part 120 may or may not be present between the multi-module 130 and the inner wall 112B.

[0033] The wireless communication unit 134 is an IC (Integrated Circuit) for wireless communication having a communication function for the sensor module 100 to communicate with an external device. The wireless communication unit 134 is connected to the antenna element 132, the ground layer 133, and the control unit 135 via wiring on the wiring board 131. The wireless communication unit 134, the antenna element 132, and the control unit 135 may be connected to each other by wiring provided on the upper surface of the wiring board 131, for example. The wireless communication unit 134 and the ground layer 133 may be connected to each other by a via or the like penetrating the wiring board 131 in the thickness direction (Z direction). The wireless communication unit 134 is connected to a power cable 140 via the wiring on the wiring board 131, and receives power from the outside of the sensor module 100 via the power cable 140.

[0034] The wireless communication unit 134 is capable of communicating according to a communication protocol of BLE (Bleutooth Low Energy (registered trademark)) as an example, but may be configured to communicate according to a communication protocol such as LTE (Long Term Evolution). The wireless communication unit 134 outputs a transmission signal including detection data of the sensor 136 input from the control unit 135 to the antenna element 132. The transmission signal output from the wireless communication unit 134 is radiated from the antenna element 132 to the slit 111D, and is radiated from the slit 111D to the outside of the sensor module 100.

[0035] The control unit 135 performs overall control of the sensor module 100. The control unit 135 is, for example, a microcomputer, and includes a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), an internal bus, and the like.

[0036] The control unit 135 is connected to the wireless communication unit 134 and the sensor 136 via the wiring of the wiring board 131, acquires detection data from the sensor 136, and causes the wireless communication unit 134 to radiate a transmission signal including the detection data to the antenna element 132. The control unit 135 is also connected to a power cable 140 via the wiring of the wiring board 131, and receives power from outside the sensor module 100 via the power cable 140.

[0037] The sensor 136 is, for example, a strain sensor (strain gauge), an accelerometer, a thermometer, or the like, and detects the strain, acceleration, temperature, and the like of the metal member 110. The sensor 136 is connected to the control unit 135 via the wiring of the wiring board 131, and outputs detection data to the control unit 135. The sensor 136 is also connected to a power cable 140 via the wiring of the wiring board 131, and receives a supply of power from outside the sensor module 100 via the power cable 140.

[0038] In the sensor module 100 described above, the antenna element 132 is provided near the inner walls 112A and 112B of the slit 111D, and electromagnetic field coupling is obtained between the antenna element 132 and the slit 111D, so that the metal member 110 having the slit 111D functions as a parasitic element.

[0039] When the antenna element 132 of the multi-module 130 is fed by the wireless communication unit 134, radio waves emitted by the antenna element 132 propagate to the slit 111D, and resonance occurs in the slit 111D, causing the radio waves to be emitted outside the sensor module 100. In this way, the metal member 110 functions as a parasitic element. A transmission signal output by the wireless communication unit 134 is emitted from the slit 111D of the metal member 110 to the outside of the sensor module 100. Since the transmission signal includes detection data of the sensor 136, if a device external to the sensor module 100 receives the radio waves emitted from the sensor module 100, it is possible to obtain detection data representing information such as distortion, acceleration, and temperature detected by the sensor 136.

[0040] As an example, the length of one revolution of slit 111D may be set to the electrical length of one wavelength at the frequency (communication frequency) of radio waves emitted from wireless communication unit 134 of multi-module 130 at the boundary between side surface 111C and recess 112. That is, the length of one revolution may be set to the electrical length of one wavelength at the communication frequency of multi-module 130 at the part of slit 111D located on the outermost side in the radial direction.

[0041] As an example, the length of one circumference of the slit 111D on the surface of the bottom 112C located at the innermost position in the radial direction may be set to be the electrical length of one wavelength at the communication frequency of the multi-module 130. As an example, the length of one circumference of the slit 111D may be set to be the electrical length of one wavelength at the communication frequency of the multi-module 130 at any radial position between the outermost position in the radial direction of the slit 111D (the boundary between the side surface 111C and the recess 112) and the surface of the innermost bottom 112C.

[0042] Moreover, the length of one revolution of the slit 111D as described above does not have to be strictly the electrical length of one wavelength at the communication frequency of the multi-module 130. The resin part 120 and the multi-module 130 are disposed in the recess 112 of the metal member 110. When the impedance characteristics of the metal member 110 fluctuate due to the resin part 120 and the multi-module 130 being disposed in the recess 112, the length of one revolution of the slit 111D may be adjusted to be shorter or longer than the electrical length of one wavelength at the communication frequency of the multi-module 130 so that the impedance of the slit 111D is matched. The impedance of the slit 111D may be matched by adjusting the length of one revolution of the slit 111D and the capacitance of the capacitor of the matching circuit 132A or the inductance of the coil of the matching circuit 132A. The purpose of setting the length of one revolution of the slit 111D to the electrical length of one wavelength at the frequency (communication frequency) of the radio wave radiated from the radiation part of the multi-module 130 includes the adjustment of the length of the slit 111D in this manner.

[0043] <Block configuration> Fig. 6 is a block diagram showing the configuration of the sensor module 100. Fig. 6 shows the antenna element 132, wireless communication unit 134, control unit 135, and sensor 136 in the multi-module 130 of the sensor module 100, as well as the power cable 140.

[0044] The sensor 136 has an analog sensor 136A, an analog circuit 136B, and an A / D (Analog to Digital) converter 136C. Analog data detected by the analog sensor 136A undergoes signal processing such as noise removal in the analog circuit 136B, is converted into digital data in the A / D converter 136C, and is output as detection data to the control unit 135. The sensor 136 may be a digital sensor, and may include a battery instead of the power cable 140. These will be described later with reference to FIG. 11.

[0045] <S11パラメータ> Fig. 7 is a diagram showing frequency characteristics of the S11 parameter of the sensor module 100. In Fig. 7, the horizontal axis represents frequency (GHz) and the vertical axis represents the S11 parameter (dB). The S11 parameter represents a reflection coefficient of power reflected from the slit 111D to the antenna element 132 with respect to power input from the antenna element 132 to the slit 111D.

[0046] FIG. 7 shows results obtained by electromagnetic field simulation for two simulation models of the sensor module 100 when the communication frequency of the multi-module 130 is set to 2.44 (GHz) as an example.

[0047] The characteristic indicated by the dashed line indicates the S11 parameter obtained in simulation model 1 in which the diameter of metal member 110 is 62 mm, the relative dielectric constant of resin part 120 is 1.7, and the gap between inner walls 112A and 112B of slit 111D is 3 mm. The characteristic indicated by the solid line indicates the S11 parameter obtained in simulation model 2 in which the diameter of metal member 110 is 62 mm, the relative dielectric constant of resin part 120 is 3.1, and the gap between inner walls 112A and 112B of slit 111D is 2 mm. The resonance frequency of slit 111D was set to 2.44 GHz.

[0048] The minimum values ​​of the S11 parameter for both simulation models 1 (dashed line) and 2 (solid line) were obtained at 2.44 GHz, and were -40.70 dB and -42.41 dB, respectively. It was found that both simulation models 1 (dashed line) and 2 (solid line) had resonance at 2.44 GHz, and that a wide band with extremely little reflection of -10 dB or less was obtained around 2.44 GHz. Simulation model 1 (dashed line) obtained a wider band than simulation model 2 (solid line).

[0049] <Directivity simulation results> 8 is a diagram showing the results of a simulation of the directivity of the sensor module 100. The diagram shows the directivity on the XY plane, the XZ plane, and the YZ plane when the communication frequency of the multi-module 130 is set to 2.44 (GHz) as an example. On the XY plane, the 0 degree direction is the +X direction, and the -90 degree direction is the +Y direction. On the XZ plane, the 0 degree direction is the +Z direction, and the 90 degree direction is the +X direction. On the YZ plane, the 0 degree direction is the +Z direction, and the 90 degree direction is the +Y direction.

[0050] In the XY plane, a roughly uniform directivity was obtained. In the XZ plane, the radiation was slightly stronger on the +X side where the antenna element 132 was located than on the -X side. In the YZ plane, the radiation was stronger in the lateral direction than in the vertical direction.

[0051] As described above, in the sensor module 100, the multi-module 130 is disposed inside the resin part 120 in the recess 112 of the metal member 110, and the metal member 110 having the slit 111D functions as a parasitic element.

[0052] Therefore, it is possible to provide a sensor module 100 in which the metal member 110 can be used as a radiating element. Also, as shown in Fig. 7, there is little reflection, and as shown in Fig. 8, uniform directivity can be obtained. Therefore, it is possible to provide a sensor module 100 with good radiation characteristics.

[0053] Moreover, the recess 112 constitutes the annular slit 111D, so that uniform directivity can be obtained in a plan view. Moreover, by providing the recess 112 on the side surface 111C of the metal member 110, the slit 111D can be easily constituted.

[0054] Furthermore, the metal member 110 has a through hole 113 that passes through the center in a plan view. The metal member 110 having such a through hole 113 in the center can be used as a bearing holder, for example. A bearing holder is a fixture that holds a bearing. By using the metal member 110 as a bearing holder, detection data that indicates the distortion, acceleration, temperature, etc. of the bearing can be transmitted to an external device by the sensor module 100.

[0055] Furthermore, since the antenna element 132 extends along the extension direction of the annular recess 112, radio waves are efficiently propagated to the slit 111D formed by the recess 112, the metal member 110 can be used as a radiating element, and a sensor module 100 with better radiation characteristics can be provided.

[0056] Furthermore, since the antenna element 132 is positioned near the inner walls 112A and 112B of the slit 111D, electromagnetic field coupling is obtained between the antenna element 132 and the slit 111D, making it easier for resonance to occur in the slit 111D, and a sensor module 100 can be provided in which the metal member 110 can be used as a radiating element and which has better radiation characteristics.

[0057] Furthermore, since the antenna element 132, the matching circuit 132A, the ground layer 133, the wireless communication unit 134, the control unit 135, and the sensor 136 are mounted on the wiring board 131, manufacturing is easy.

[0058] Furthermore, since the multi-module 130 having the wiring board 131, antenna element 132, matching circuit 132A, ground layer 133, wireless communication unit 134, control unit 135, and sensor 136 is arranged inside the resin part 120, manufacturing is easy.

[0059] <First Modification> 9 is a diagram showing a metal member 110M1 of a first modified example of the embodiment. The metal member 110M1 is divided into an upper metal member 110A and a lower metal member 110B. The metal member 110A is a portion above the inner wall 112A of the metal member 110 shown in FIGS. 1 to 5, and the metal member 110B is a portion below the inner wall 112A of the metal member 110 shown in FIGS. 1 to 5. Therefore, a bottom portion 112C is provided in the center of the upper surface of the metal member 110B.

[0060] The metal member 110A is an example of a first metal member provided on the upper side (first side), and the metal member 110B is an example of a second metal member provided on the lower side (second side) and fixed to the metal member 110A. The recess 112 is provided at the joint between the metal members 110A and 110B. By joining such metal members 110A and 110B, a metal member having the same configuration as the metal member 110 shown in Figures 1 to 5 is obtained.

[0061] <Second Modification> 10 is a diagram showing a sensor module 100M2 according to a second modified example of the embodiment. The sensor module 100M2 has a configuration in which the multi-module 130 of the sensor module 100 shown in FIGS.

[0062] The multi-module 130M2 is U-shaped in a plan view. The substrate 131M2 of the multi-module 130M2 is U-shaped, and the distance in the Y direction between the ends 131MA2 and 131MB2 is wider than the outer diameter of the bottom 112C of the metal member 110. Therefore, the bottom 112C of the metal member 110 can be inserted between the ends 131MA2 and 131MB2 of the U-shaped substrate 131M2, and the multi-module 130M2 can be easily attached to the metal member 110.

[0063] <Third Modification> 11 is a block diagram showing a configuration of a sensor module 100M3 according to a third modified example of the embodiment. The sensor module 100M3 differs from the sensor module 100 (see FIG. 6) including the analog sensor 136A and the power cable 140 in that the sensor module 100M3 includes a digital sensor 136M3 and a battery 140M3. The digital sensor 136M3 outputs detection data as digital data to the control unit 135. The battery 140M3 may be mounted on the upper surface of the wiring board 131 and housed inside the recess 112 of the metal member 110, for example.

[0064] The sensor module 100M3 can reduce the number of parts by including the digital sensor 136M3. Also, since the sensor module 100M3 has the built-in battery 140M3, there is no part protruding from the metal member 110 like the power cable 140, and the appearance can be simplified. Also, since the sensor module 100M3 can be operated by the power supplied from the battery 140M3, it can be used even in places where there is no power supply source that supplies power to the sensor module 100 via the power cable 140.

[0065] <Fourth and Fifth Modifications> 12 and 13 are diagrams showing sensor modules 100M4 and 100M5 of the fourth and fifth modified examples. The sensor module 100M4 is obtained by replacing the metal member 110 of the sensor module 100 shown in FIG. 5 with a metal member 110M4. The metal member 110M4 is rectangular (quadrilateral) in a plan view. A rectangle is an example of a polygon. The shape of the metal member 110M4 in a plan view is not limited to a quadrangle, and may be a triangle or a polygon having five or more sides and vertices.

[0066] The outer shape of the metal member 110M5 of the sensor module 100M5 is a shape obtained by cutting out both ends of the Y direction side of the circular metal member 110 shown in Fig. 5 along the X direction in plan view. The sensor module 100M5 has a multi-module 130M5 having a shape in which both ends of the Y direction side are cut out along the X direction, instead of the multi-module 130 shown in Fig. 5. The multi-module 130M5 has a substrate 131M5 having a shape in which both ends of the Y direction side are cut out along the X direction. Note that a part of the metal member 110M4 of the sensor module 100M4 shown in Fig. 12 may be cut out in plan view.

[0067] According to the fourth and fifth modified examples, the sensor modules 100M4 and 100M5 having various shapes can be realized.

[0068] The above describes an exemplary embodiment of a sensor module of the present invention. However, the present invention is not limited to the specifically disclosed embodiment, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of symbols]

[0069] 100, 100M2, 100M3, 100M4, 100M5 Sensor Module 110, 110M1, 110A, 110B, 110M4, 110M5 Metallic parts 120 Resin part 130, 130M2, 130M5 Multi-Module 131, 131M5 Wiring board 132 Antenna Element 133 Ground Layer 134 Wireless Communication Division 135 Control Unit 136 Sensors 136A Analog Sensor 136M3 Digital Sensor 140 Power Cable 140M3 Battery

Claims

1. A metal member having a side surface extending in an annular shape and a recess recessed from the side surface and provided in an annular shape over the side surface; A resin portion embedded in the recess; a radiation portion provided inside the resin portion and configured to radiate radio waves; a wireless communication unit provided inside the resin portion and connected to the radiation unit; A sensor connected to the wireless communication unit; Including, The metal member is insulated from the radiating portion by the resin portion and functions as a parasitic element.

2. The sensor module according to claim 1 , wherein the recess constitutes an annular slit.

3. The sensor module according to claim 1 , wherein an outer shape of the metal member is, in a plan view, a circle, a polygon, or a shape obtained by cutting out a part of a circle or a polygon.

4. The sensor module according to claim 1 , wherein the metal member has a through hole passing through a center thereof in a plan view.

5. the metal member includes a first metal member provided on a first side in a direction penetrating the annular recess, and a second metal member provided on a second side in a direction penetrating the annular recess and fixed to the first metal member, The sensor module according to claim 1 , wherein the annular recess is provided at a joint between the first metal member and the second metal member.

6. The sensor module according to claim 1 , wherein the radiating portion extends in a direction in which the annular recess extends.

7. The sensor module according to claim 1 , wherein the radiating portion is provided near an inner wall of the recess.

8. The resin portion further includes a substrate provided inside the resin portion, The sensor module according to claim 1 , wherein the emitting portion, the wireless communication portion, and the sensor are mounted on the substrate.

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