Impact sensor

Abstract

To provide an impact sensor that reduces the wrong detection of impact.SOLUTION: An impact sensor 300 includes a frame part 2, a rotary movable element 3 that is supported through a shaft part 33 with respect to the frame part 2 and is rotatable using the shaft part 33 as a rotary axis O, a first movable electrode disposed in the rotary movable element 3, and a fixed electrode disposed at a position facing the first movable electrode. The rotary movable element 3 is supported by the shaft part 33 so that a center of gravity G of the rotary movable element 3 is separated from the rotary shaft, and upon the impact in a direction perpendicular to a radius direction of the rotary movable element 3, is displaceable in a mode of rotating about the rotary axis O. The first movable electrode is disposed at a position apart from the rotary axis O, and the impact is detected by the contact between the first movable electrode and the fixed electrode as the rotary movable element 3 is displaced. The rotary movable element 3 and the frame part 2 are connected by a beam part 34 whose longitudinal direction is a direction intersecting with a rotary shaft direction. The beam part 34 is deformable as the rotary movable element 3 is displaced.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an impact sensor. [Background technology]

[0002] Patent document 1 discloses that a torsion bar supports a weight, and when an impact (acceleration) of a predetermined value or greater is applied, the weight rotates (displaces), and the impact is detected when an electrode placed on the weight comes into contact with an electrode placed opposite the weight. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-161500 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the configuration of Patent Document 1, even if an impact is applied from a direction different from the displacement direction of the weight, the weight may rotate (displace) and the electrodes may come into contact with each other, which may result in an erroneous detection that the impact occurred from that displacement direction.

[0005] SUMMARY OF THE INVENTION It is therefore an object of one aspect of the present invention to provide an impact sensor that reduces false detections due to impacts on other axes. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided an impact sensor comprising: a stator; a first movable element supported on the stator via an axis portion and rotatable around the axis portion as a rotation axis; a first movable electrode arranged on the first movable element; and a fixed electrode arranged opposite the first movable electrode, wherein the first movable element is supported on the axis portion so that the center of gravity of the first movable element is spaced from the rotation axis, and is displaceable in a manner that rotates around the rotation axis when it receives an impact in a direction perpendicular to the rotation axis direction of the first movable element and a radial direction connecting the rotation axis and the center of gravity among directions intersecting the rotation axis direction, the first movable electrode is arranged at a position spaced from the rotation axis, and detects an impact when the first movable electrode and the fixed electrode come into contact due to displacement of the first movable element, and the first movable element and the stator are connected by a beam portion whose longitudinal direction is in a direction intersecting the rotation axis direction, and the beam portion is deformable in accordance with the displacement of the first movable element. [Effects of the Invention]

[0007] According to one aspect of the present invention, the beam portion is a member whose longitudinal direction is perpendicular to the rotation axis direction, thereby suppressing displacement of the first mover due to impact (acceleration) in the direction perpendicular to the rotation axis direction. Therefore, by suppressing displacement of the first mover due to impact (acceleration) in the rotation axis direction and the direction perpendicular to the rotation axis direction, it is possible to reduce erroneous detection of impact (acceleration) in a direction other than the thickness direction as an impact in the thickness direction. Furthermore, when the first mover is displaced while rotating around the rotation axis, the beam portion deforms in response to the displacement, and therefore can apply a restoring force to the first mover. Therefore, even when a large impact (acceleration) is applied from the thickness direction, the restoring force reduces the displacement and displacement speed of the first mover, thereby reducing damage to the first mover. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of the impact sensor of the present embodiment. [Figure 2] FIG. 2 is a plan view of the substrate of the impact sensor according to this embodiment. [Figure 3] FIG. 3 is a rear view of the substrate of the impact sensor according to this embodiment. [Figure 4] FIG. 4 is a plan view of the cover of the impact sensor according to this embodiment. [Figure 5] FIG. 5 is a cross-sectional view taken along line AA in FIGS. [Figure 6] FIG. 6 is a cross-sectional view taken along line BB in FIGS. 2 to 4, showing the state of the rotary movable element before the shock sensor receives an impact in the −Z direction, or the state of the rotary movable element before the shock sensor receives an impact in the +Z direction. [Figure 7] FIG. 7 is a cross-sectional view taken along the line BB in FIGS. 2 to 4, showing the state of the rotary movable element when the impact sensor receives an impact in the -Z direction. [Figure 8] FIG. 8 is a cross-sectional view taken along the line BB in FIGS. 2 to 4, showing the state of the rotary movable element when the impact sensor receives an impact in the +Z direction. [Figure 9] FIG. 9 is a cross-sectional view taken along line CC in FIGS. 2 to 4, showing the state of the beam portion before the impact sensor receives an impact in the −Z direction, or the state of the beam portion before the impact sensor receives an impact in the +Z direction. [Figure 10] FIG. 10 is a cross-sectional view taken along line CC in FIGS. 2 to 4, showing the state of the beam portion when the impact sensor receives an impact in the -Z direction. [Figure 11] FIG. 11 is a cross-sectional view taken along line CC in FIGS. 2 to 4, showing the state of the beam portion when the impact sensor receives an impact in the +Z direction. [Figure 12] FIG. 12 is a detailed view of a portion of FIG. [Figure 13] FIG. 13 is a diagram showing a case where an impact is applied from the X direction in the arrangement shown in FIG. 12 and the translational mover comes into contact with the first member (buffer electrode). [Figure 14] FIG. 14 shows a state in which an impact is received from the X direction in the arrangement shown in FIG. 12, in which the translational movable element further presses the first member (buffer electrode) from the state shown in FIG. 13, deforming the third and fourth members that support the first and second members, and causing the translational movable element to further displace together with the first member (buffer electrode) and come into contact with the stopper. [Figure 15]FIG. 15 is a plan view of a first modified example of the substrate of the impact sensor according to this embodiment. [Figure 16] FIG. 16 is a plan view of a second modified example of the substrate of the impact sensor according to this embodiment. [Figure 17] FIG. 17 is a schematic diagram of an electronic tag including an impact sensor according to this embodiment. [Figure 18] FIG. 18 is a circuit diagram showing an example of a latch circuit that constitutes an electronic tag. [Figure 19] FIG. 19 is a flowchart showing the operation flow of an electronic tag. [Figure 20] FIG. 20 is a diagram for explaining how to use an electronic tag. DETAILED DESCRIPTION OF THE INVENTION

[0009] The embodiments described below are not limited to the drawings described by the brief description of the drawings.

[0010] A first aspect of the present invention is an impact sensor comprising: a stator; a first movable element supported on the stator via an axis portion and rotatable around the axis portion as a rotation axis; a first movable electrode arranged on the first movable element; and a fixed electrode arranged opposite the first movable electrode, wherein the first movable element is supported on the axis portion so that the center of gravity of the first movable element is spaced from the rotation axis, and is displaceable in a manner that rotates around the rotation axis when it receives an impact in a direction perpendicular to the rotation axis direction of the first movable element and a radial direction connecting the rotation axis and the center of gravity among directions intersecting the rotation axis direction, the first movable electrode being arranged at a position spaced from the rotation axis, and detecting the impact when the first movable electrode and the fixed electrode come into contact due to displacement of the first movable element, the first movable element and the stator being connected by a beam portion whose longitudinal direction is a direction intersecting the rotation axis direction, and the beam portion is deformable in accordance with the displacement of the first movable element.

[0011] According to the first aspect, the beam portion is a member whose longitudinal direction is perpendicular to the rotation axis direction, and therefore can suppress displacement of the first mover due to impact (acceleration) in the direction perpendicular to the rotation axis direction. Therefore, by suppressing displacement of the first mover due to impact (acceleration) in the rotation axis direction and the direction perpendicular to the rotation axis direction, it is possible to reduce erroneous detection of impact (acceleration) in a direction other than the thickness direction as an impact in the thickness direction. Furthermore, when the first mover is displaced while rotating around the rotation axis, the beam portion deforms in response to the displacement, and therefore can apply a restoring force to the first mover. Therefore, even when a large impact (acceleration) is applied from the thickness direction, the restoring force reduces the displacement and displacement speed of the first mover, thereby reducing damage to the first mover.

[0012] A second aspect of the present invention is an impact sensor in which, in the first aspect, the first movable element includes a first rotating movable element including the center of gravity and a second rotating movable element extending from the first rotating movable element on the opposite side of the rotation axis of the center of gravity, and the beam portion connects the first rotating movable element and the stator and is deformable in accordance with the displacement of the first rotating movable element.

[0013] According to the second aspect, impacts (accelerations) in both thickness directions can be detected separately. Furthermore, since the beams are deformable in both thickness directions, even if a large impact (acceleration) is applied from either thickness direction, the restoring force of the beams reduces the displacement and displacement speed of the rotary movable element, thereby reducing damage to the first movable element.

[0014] A third aspect of the present invention is an impact sensor according to the second aspect, wherein the first movable electrode includes a first rotating movable electrode arranged on the first rotating movable element, and the fixed electrode includes a first fixed electrode arranged in a position opposite to the first rotating movable electrode, and the first rotating movable electrode comes into contact with the first fixed electrode when the first rotating movable electrode is displaced toward the first fixed electrode.

[0015] According to the third aspect, an impact in the direction in the thickness direction in which the first rotating movable electrode (first rotating movable element) moves toward the first fixed electrode can be detected by contact between the first rotating movable electrode and the first fixed electrode, resulting in an impact sensor that can detect an impact from one direction in the thickness direction with a simple configuration.

[0016] A fourth aspect of the present invention is an impact sensor according to the second or third aspect, wherein the first movable electrode includes a second rotating movable electrode arranged on the second rotating movable element, the fixed electrode includes a second fixed electrode arranged at a position opposite to the second rotating movable electrode, and the second rotating movable electrode comes into contact with the second fixed electrode when the second rotating movable electrode is displaced toward the second fixed electrode.

[0017] With the above configuration, an impact in the direction in the thickness direction in which the first rotating movable electrode (first rotating movable element) moves away from the first fixed electrode, i.e., an impact in the direction in which the second rotating movable electrode (second rotating movable element) moves toward the second fixed electrode, can be detected by contact between the second rotating movable electrode and the second fixed electrode, resulting in an impact sensor that can detect an impact from the other direction in the thickness direction with a simple configuration.

[0018] A fifth aspect of the present invention is an impact sensor according to the second aspect, wherein the first movable electrode includes a first rotating movable electrode arranged on the first rotating movable element and a second rotating movable electrode arranged on the second rotating movable element, and the fixed electrode includes a first fixed electrode arranged at a position opposite the first rotating movable electrode and a second fixed electrode arranged at a position opposite the second rotating movable electrode, and when the first rotating movable electrode is displaced toward the first fixed electrode, the first rotating movable electrode comes into contact with the first fixed electrode and the second rotating movable electrode moves away from the second fixed electrode, and when the second rotating movable electrode is displaced toward the second fixed electrode, the first rotating movable electrode moves away from the first fixed electrode and the second rotating movable electrode comes into contact with the second fixed electrode.

[0019] According to the fifth aspect, an impact in the thickness direction in which the first rotating movable electrode (first rotating movable element) moves toward the first fixed electrode is detected by contact between the first rotating movable electrode and the first fixed electrode, and the second rotating movable electrode is positioned away from the second fixed electrode, and an impact in the thickness direction in which the second rotating movable electrode (second rotating movable element) moves toward the second fixed electrode is detected by contact between the second rotating movable electrode and the second fixed electrode, and the first rotating movable electrode is positioned away from the first fixed electrode, resulting in an impact sensor with a simple configuration that can individually detect impacts in both thickness directions without erroneous detection.

[0020] A sixth aspect of the present invention is an impact sensor which is any one of the first to fifth aspects, and wherein both longitudinal ends of the beam portion are arranged to sandwich the rotation axis when viewed from the direction of the rotation axis.

[0021] According to the sixth aspect, when the rotary movable element rotates around the rotation axis, the beam portion can be reliably deformed and a restoring force can be generated in the beam portion.

[0022] A seventh aspect of the present invention is an impact sensor according to any one of the first to sixth aspects, wherein the width of the beam portion in the direction of the rotation axis narrows from the stator toward the first movable element.

[0023] According to the seventh aspect, when the first movable element rotates around the rotation axis, the beam portion can be deformed approximately uniformly throughout the entire longitudinal direction, thereby reducing stress concentration in specific areas (especially the connection position of the beam portion with the stator) and increasing the durability of the beam portion.

[0024] An eighth aspect of the present invention is an impact sensor which is any one of the second to seventh aspects, wherein the width of the second rotating movable element in the rotational axis direction is narrower than the width of the first rotating movable element in the rotational axis direction, the beam portions are arranged in a pair so as to sandwich the second rotating movable element from the rotational axis direction, and the shaft portions are arranged in a pair so as to sandwich the pair of beam portions from the rotational axis direction and are connected to the first rotating movable element.

[0025] According to the eighth aspect, the area occupied by the integrated body of the first movable element, the shaft portion, and the beam portion can be reduced, thereby miniaturizing the impact sensor in the planar direction. Furthermore, since the distance between the pair of shaft portions is longer than the distance between the pair of beam portions, rotation of the pair of shaft portions about the axis of rotation in the thickness direction of the first movable element can be suppressed, and false detection of impacts due to such rotation can be reduced.

[0026] A ninth aspect of the present invention is an impact sensor which is any one of the second to seventh aspects, wherein the width of the second rotating movable element in the rotational axis direction is narrower than the width of the first rotating movable element in the rotational axis direction, the shaft portions are arranged in a pair so as to sandwich the second rotating movable element from the rotational axis direction, and the beam portions are arranged in a pair so as to sandwich the pair of shaft portions from the rotational axis direction.

[0027] According to the ninth aspect, the area occupied by the integrated body of the first movable element, the shaft portion, and the beam portion can be reduced, thereby miniaturizing the impact sensor in the planar direction. Furthermore, since the distance between the pair of shaft portions is longer than the distance between the pair of beam portions, rotation of the pair of shaft portions about the axis of rotation in the thickness direction of the first movable element can be suppressed, and erroneous detection of impact due to such rotation can be reduced.

[0028] A tenth aspect of the present invention is an impact sensor according to the eighth aspect, wherein the first movable electrode includes a first rotating movable electrode arranged on the first rotating movable element and a second rotating movable electrode arranged on the second rotating movable element, and the first rotating movable electrode and the second rotating movable electrode are arranged at a position between a pair of the beam portions in the rotation axis direction.

[0029] According to the tenth aspect, the first movable element can be formed in a shape that is perpendicular to the rotation axis direction and mirror-symmetrical about the line connecting the rotation axis and the center of gravity, thereby reducing unnecessary vibration components of the first movable element that may occur when the impact sensor receives an impact (acceleration), and reducing false detection of impact due to these unnecessary vibration components.

[0030] An eleventh aspect of the present invention is an impact sensor according to the ninth aspect, wherein the first movable electrode includes a first rotating movable electrode arranged on the first rotating movable element and a second rotating movable electrode arranged on the second rotating movable element, and the first rotating movable electrode and the second rotating movable electrode are arranged at a position between a pair of the shaft portions in the direction of the rotation axis.

[0031] According to the eleventh aspect, the first movable element can be formed in a shape that is perpendicular to the rotation axis direction and mirror-symmetrical about the line connecting the rotation axis and the center of gravity, thereby reducing unnecessary vibration components of the first movable element that may occur when the impact sensor receives an impact (acceleration), and reducing false detection of impact caused by these unnecessary vibration components.

[0032] A twelfth aspect of the present invention is an impact sensor according to any one of the eighth to eleventh aspects, wherein the width of the second rotating movable element in the direction of the rotation axis becomes narrower as it moves away from the first rotating movable element.

[0033] According to the 12th aspect, when the second rotating movable electrode contacts the second fixed electrode, the second rotating movable element can be deformed approximately uniformly in its longitudinal direction, thereby reducing stress concentration at specific parts of the second rotating movable element (particularly the connection position of the second rotating movable element with the first rotating movable element) and increasing the durability of the second rotating movable element.

[0034] A thirteenth aspect of the present invention is an impact sensor according to any one of the second to twelfth aspects, wherein the second rotary movable element has a slit extending in the radial direction.

[0035] According to the thirteenth aspect, the position of the center of gravity of the first mover can be set to a desired position.

[0036] A 14th aspect of the present invention is an impact sensor in which, in any one of the 1st to 13th aspects, the shaft portions are arranged in a pair so as to sandwich the first movable element from the direction of the rotation axis.

[0037] According to the fourteenth aspect, the first mover can be rotated stably around the rotation axis.

[0038] A 15th aspect of the present invention is an impact sensor in which, in any one of the second to fourteenth aspects, a specific portion of the first rotating movable element where the first rotating movable electrode is arranged is set to have lower rigidity than portions of the first rotating movable element other than the specific portion.

[0039] According to the fifteenth aspect, the contact time between the first rotating movable electrode and the first fixed electrode can be extended. This allows the circuit that detects contact between the first rotating movable electrode and the first fixed electrode to be configured to respond at a low frequency. This reduces the frequency of false detection of noise as an impact signal, and also makes it possible to reduce the power consumption of the circuit.

[0040] A 16th aspect of the present invention is an impact sensor which is any one of the second to fifteenth aspects, wherein the first movable electrode includes a first rotating movable electrode arranged on the first rotating movable element and a second rotating movable electrode arranged on the second rotating movable element, the fixed electrode includes a first fixed electrode arranged at a position opposite the first rotating movable electrode and a second fixed electrode arranged at a position opposite the second rotating movable electrode, and a cover portion is joined to the stator, and the first fixed electrode and the second fixed electrode are arranged on the main surface of the cover portion facing the stator.

[0041] According to the sixteenth aspect, the first fixed electrode and the second fixed electrode can be arranged with a simple configuration.

[0042] A 17th aspect of the present invention is an impact sensor which is any one of the first to sixteenth aspects, wherein the stator, the shaft portion, the first movable element, and the beam portion are one piece and formed from a laminate in which an active layer is stacked on a support layer, the portion of the one piece relating to the stator is formed from the laminate, and the portion of the one piece relating to the shaft portion, the first movable element, and the beam portion are formed from the active layer obtained by removing the support layer from the laminate.

[0043] According to the seventeenth aspect, the impact sensor can be formed by etching the laminate, and impact sensors can be easily manufactured in large quantities.

[0044] An 18th aspect of the present invention is an impact sensor according to any one of the first to seventeenth aspects, further comprising a second movable element supported on the stator via an elastic body, and a second movable electrode arranged on the second movable element, wherein the stator includes a first connection electrode electrically connected to the first movable electrode via the shaft portion and / or the beam portion, and a second connection electrode electrically connected to the second movable electrode via the elastic body and arranged so as to be insulated from the first connection electrode, and wherein the displacement direction of the second movable element is perpendicular to the displacement direction of the first movable element.

[0045] According to the eighteenth aspect, the impact sensor can independently detect an impact (acceleration) in the thickness direction and an impact in a direction perpendicular to the thickness direction.

[0046] A 19th aspect of the present invention is an impact sensor according to any one of the second to seventeenth aspects, further comprising a second movable element supported on the stator via an elastic body, and a second movable electrode arranged on the second movable element, wherein the stator includes a first connection electrode electrically connected to the first movable electrode via the shaft portion and / or the beam portion, and a second connection electrode electrically connected to the second movable electrode via the elastic body and arranged so as to be insulated from the first connection electrode, wherein the displacement direction of the second movable element is perpendicular to the displacement direction of the first movable element, and the elastic body and the second movable element are arranged in a position facing the first rotating movable element in a direction intersecting the displacement direction of the second movable element and facing the second rotating movable element in the displacement direction of the second movable element.

[0047] According to the 19th aspect, the elastic body and the second movable element are arranged in an L-shaped area formed by the first rotating movable element and the second rotating movable element, so that the impact sensor that independently detects impact (acceleration) in the thickness direction and impact in a direction perpendicular to the thickness direction can be miniaturized in the surface direction.

[0048] Hereinafter, embodiments will be described with reference to the drawings.

[0049] [Appearance of the Impact Sensor 300] Fig. 1 is a perspective view of an impact sensor 300 of this embodiment. As shown in Fig. 1, the impact sensor 300 has a laminated structure of a substrate 1 and a lid portion 5. The substrate 1 is formed of an SOI (Silicon On Insulator) wafer, as described below. The lid portion 5 is formed of, for example, glass.

[0050] A first external electrode 53, a second external electrode 54, a third external electrode 55, a fourth external electrode 56, and a fifth external electrode 57 are arranged on the upper surface of the lid portion 5, and as will be described later, these external electrodes are electrically connected to the substrate 1. Furthermore, these external electrodes are connected to a latch circuit 600k, which will be described later.

[0051] [Configuration of the substrate 1, the rotary movable element 3, and the lid portion 5] Fig. 2 is a plan view of the substrate 1 of the impact sensor 300 according to this embodiment. Fig. 3 is a rear view of the substrate 1 of the impact sensor 300 according to this embodiment. Fig. 4 is a plan view of the lid 5 of the impact sensor 300 according to this embodiment. Fig. 5 is a cross-sectional view taken along line AA in Figs. 2 to 4.

[0052] In the drawings, the X, Y, and Z directions are perpendicular to one another. In the following description, the "X direction" may be referred to as the "left-right direction," the "Y direction" as the "up-down direction," the "+X direction" as the "right direction," the "-X direction" as the "left direction," the "+Y direction" as the "upward direction," and the "-Y direction" as the "downward direction." The "Z direction" may also be referred to as the "thickness direction."

[0053] 2, the substrate 1 of the shock sensor 300 has a rectangular shape in a plan view. The substrate 1 includes a rectangular frame 2, and a rotational mover 3 (first mover), a translational mover 4X (second mover), and a translational mover 4Y (second mover) arranged inside the frame 2. The top surface of the substrate 1 (the surface facing the lid 5) is an active layer 1c, except for a groove 27 (insulating layer 1b), as described below. The frame 2 is a first connection electrode 21, except for a portion that will become a second connection electrode 22, as described below.

[0054] In the frame portion 2, a groove is formed that penetrates the substrate 1 to form the outline of the rotary movable element 3, the shaft portion 33, and the beam portion 34, leaving the connection position between the shaft portion 33 and the frame portion 2 and the connection position between the beam portion 34 and the frame portion 2, and the rotary movable element 3 is supported by the frame portion 2 via the shaft portion 33 and the beam portion 34.

[0055] As described above, the rotary mover 3 is supported by the shaft portion 33, and is rotatable around the shaft portion 33 as a rotation axis O. Here, the axial direction of the shaft portion 33 (rotation axis O) is the left-right direction (X direction). Furthermore, when the rotary mover 3 rotates, the shaft portion 33 is twisted by the rotary mover 3, and at that time a restoring force is generated that rotates the rotary mover 3 in a direction that cancels the twist, and this restoring force is applied to the rotary mover 3.

[0056] The rotary mover 3 is supported by the shaft portion 33 so that the center of gravity G of the rotary mover 3 is spaced apart from the rotation axis O.

[0057] When the impact sensor 300 is not subjected to an impact (acceleration), the direction perpendicular to the direction of the rotation axis O (left-right direction) and the radial direction of the rotation radius of the rotation movable element 3 connecting the rotation axis O and the center of gravity G (the normal direction to the main surface of the rotation movable element 3) is oriented approximately in the thickness direction (Z direction).

[0058] Therefore, the rotary movable element 3 is displaced in a manner that rotates around the rotation axis O when the impact sensor 300 receives an impact (acceleration) from a direction (Z direction) that is approximately perpendicular to the radial direction.

[0059] The rotary mover 3 includes a first rotary mover 31 including a center of gravity G, and a second rotary mover 32 extending from the first rotary mover 31 toward the rotation axis O and extending to the opposite side of the center of gravity G across the rotation axis O.

[0060] The first rotating movable element 31 includes a main body 311 including a center of gravity G, and a pair of arms 312 extending from the right-hand (+X direction) end and the left-hand (-X direction) end of the main body 311 respectively toward the rotation axis O, and an axis portion 33 is connected to the part of the arm 312 that overlaps with the rotation axis O.

[0061] Furthermore, a bent portion 313 is arranged at the center in the left-right direction of the first rotary movable element 31 (main body 311) and at the end in the radial direction, and a first rotary movable electrode 314 that contacts a first fixed electrode 51 (described later) is arranged at the tip of the bent portion 313. The bent portion 313 has a pair of beam shapes with the radial direction as the longitudinal direction on the side connected to the main body 311, and the rigidity in the thickness direction is reduced by forming the width of the beams in the left-right direction to be narrow. The connection position of the beam shape with the main body 311 is a fixed end, and the tip side of the bent portion 313 is a free end, and is configured to be elastically deformable in the thickness direction. Furthermore, the bent portion 313 is formed thinner than the portion (main body 311) of the first rotary movable element 31 other than the bent portion 313, thereby reducing the rigidity in the thickness direction. Therefore, the bending portion 313 has a fixed end at the connection position with the main body 311 and a free end at the end opposite the fixed end in the radial direction, and when the free end receives a force from the thickness direction, it elastically deforms in the thickness direction such that it displaces relative to the fixed end. In any case, any configuration can be applied to the bending portion 313 as long as it is elastically deformable in the thickness direction.

[0062] As a result, when the first rotating movable electrode 314 comes into contact with the first fixed electrode 51, the bending portion 313 elastically deforms, thereby lengthening the contact time between the first rotating movable electrode 314 and the first fixed electrode 51 and improving the reliability of impact (acceleration) detection.

[0063] In addition, the second rotating movable element 32 extends from the first rotating movable element 31 (main body 311) on the opposite side of the rotation axis O of the center of gravity G, and is formed so that the distance between its tip and the rotation axis O in the radial direction is approximately the same as the distance between the tip of the bent portion 313 (first rotating movable electrode 314) and the rotation axis O, for example.

[0064] Furthermore, a slit 35 (opening) with its longitudinal direction aligned with the radial direction is disposed in the center of the second rotary mover 32 in the left-right direction, and the slit 35 has a tapered shape that widens in the left-right direction toward the tip of the second rotary mover 32. This reduces the moment of inertia of the second rotary mover 32, thereby increasing the sensitivity of the rotary mover 3 to rotation (displacement), i.e., to impact (acceleration). Furthermore, by appropriately designing the dimensions of the slit 35, the position of the center of gravity G can be set to a desired position. Note that the second rotary mover 32 is not limited to a tapered shape, and may be formed so that its width in the left-right direction (direction of rotation axis, X direction) gradually narrows the further it is from the first rotary mover 31 (main body 311).

[0065] The portion of the second rotary movable element 32 that is radially outward of the slit 35 serves as a second rotary movable electrode 321 that comes into contact with a second fixed electrode 52, which will be described later.

[0066] As shown in FIG. 2, the second rotary movable element 32 has a tapered shape in which the width in the left-right direction (X direction) narrows toward the tip of the second rotary movable element 32.

[0067] As a result, when the second rotating movable electrode 321 comes into contact with the second fixed electrode 52, the second rotating movable element 32 elastically deforms, thereby lengthening the contact time between the second rotating movable electrode 321 and the second fixed electrode 52 and improving the reliability of impact (acceleration) detection. Furthermore, by forming the second rotating movable element 32 into a tapered shape as described above, the second rotating movable element 32 can be elastically deformed uniformly, thereby reducing the concentration of stress on specific parts of the second rotating movable element 32 (particularly the connection position of the second rotating movable element 32 with the main body 311).

[0068] Incidentally, the shaft 33 is a member that extends in the left-right direction, and therefore has high rigidity in the left-right direction. Therefore, even if an impact (acceleration) is applied to the impact sensor 300 in the left-right direction (X direction), a compressive or elongating force is applied to the shaft 33, but the displacement is small, so the left-right displacement of the rotary movable element 3 can be suppressed.

[0069] However, the rigidity of the shaft 33 in the direction perpendicular to the left-right direction is low. Therefore, when an impact (acceleration) in the up-down direction (Y direction) is applied to the impact sensor 300, the shaft 33 elastically deforms in the up-down direction, but the displacement is large, and as a result, the displacement of the rotary movable element 3 in the up-down direction is also large.

[0070] Then, the rotary movable element 3 displaced (vibrated) in the vertical direction can have its vibration energy converted into vibration energy in the Z direction, and can rotate around the shaft portion 33 as the rotation axis O. Therefore, there is a risk that an impact (acceleration) from the vertical direction (Y direction) will be erroneously detected as an impact (acceleration) in the thickness direction (Z direction).

[0071] Therefore, the impact sensor 300 of this embodiment has a beam portion 34 that connects the frame portion 2 and the rotary movable element 3.

[0072] The beam portion 34 is a member that is arranged to connect, for example, the frame portion 2 and the main body 311 of the first rotary movable element 31, has a longitudinal direction in the vertical direction (Y direction), and has high rigidity against forces in the longitudinal direction.

[0073] Therefore, even if an impact (acceleration) is applied to the impact sensor 300 in the vertical direction, a compressive or elongating force is applied to the beam portion 34, but the displacement is small, so it is possible to suppress the vertical displacement of the rotary movable element 3. Therefore, even if an impact is applied to the impact sensor 300 in the vertical direction (X direction), it is possible to reduce the chance of it being erroneously detected as an impact in the thickness direction (Z direction).

[0074] The longitudinal end of the beam portion 34 on the frame portion 2 side (the connection position with the frame portion 2) and the longitudinal end of the beam portion 34 on the main body 311 side are arranged so as to sandwich the rotation axis O when viewed from the rotation axis direction (X direction).

[0075] Therefore, when an impact (acceleration) is applied to the impact sensor 300 from the thickness direction (Z direction), the rotary movable element 3 rotates (displaces) around the shaft portion 33 as the rotation axis O, and at that time, the beam portion 34 can be reliably elastically deformed in the thickness direction (Z direction). Furthermore, when a large impact (acceleration) is applied to the impact sensor 300 from the thickness direction, the restoring force of the beam portion 34 can suppress the speed of displacement of the rotary movable element 3, thereby reducing damage to the rotary movable element 3.

[0076] The width of the beam portion 34 in the left-right direction is tapered, narrowing as it moves from the frame portion 2 side to the main body 311 side. More specifically, for example, line CC shown in FIGS. 2 and 3 is a line perpendicular to the rotation axis O and serves as the central axis of one of the pair of beam portions 34. This central axis passes through the left-right center of the beam portion 34 at the connection position of the beam portion 34 with the frame portion 2. The distance between the central axis and the side surface to the right of the central axis of the beam portion 34 is approximately constant in the up-down direction. The distance between the central axis and the side surface to the left of the central axis of the beam portion 34 is arranged so that it becomes shorter as it moves from the frame portion 2 to the main body 311 of the first rotary movable element 31. The shape of the other of the pair of beam portions 34 is bilaterally symmetrical to that of the first of the pair of beam portions 34. This allows the beam portion 34 to elastically deform approximately uniformly throughout, thereby reducing stress concentration in specific locations (particularly, the connection position of the beam portion 34 with the frame portion 2).

[0077] 3, 5, etc., the substrate 1 is a laminate of a silicon substrate 1a, an insulating layer 1b, and an active layer 1c, while the frame portion 2 is formed of a laminate of a support layer (silicon substrate 1a, insulating layer 1b) and an active layer 1c, and the portions of the substrate 1 other than the frame portion 2, i.e., the rotary movable element 3, the shaft portion 33, the beam portion 34, and the translation movable element 4 and spring portion 42 described below, are formed of the active layer 1c obtained by removing the support layer (silicon substrate 1a, insulating layer 1b) from the laminate. Note that the shaft portion 33, the beam portion 34, and the translation movable element 4 and spring portion 42 described below may also be configured to be formed of the insulating layer 1b and the active layer 1c from which the silicon substrate 1a has been removed. The groove portion 27 is formed by removing the active layer 1c (or the active layer 1c and the insulating layer 1b) in the frame portion 2, and is a recess having an opening in the active layer 1c (or the insulating layer 1b) formed by removing the active layer 1c (or the active layer 1c and the insulating layer 1b) in the laminate that forms the frame portion 2 according to the outline of the groove portion 27, and a bottom surface made of the insulating layer 1b (or the silicon substrate 1a) exposed in the opening.

[0078] As shown in Fig. 5 and other figures, the lid portion 5 is bonded to the active layer 1c of the substrate 1. As shown in Fig. 4, the lid portion 5 has a first recess 58 formed to match the outer shapes of the portions other than the frame portion 2, namely, the rotary mover 3, the shaft portions 33, the beam portions 34, and the translational mover 4 and spring portions 42 (described later). Therefore, the lid portion 5 is bonded to the frame portion 2 and can avoid interference with the rotary mover 3, the shaft portions 33, the beam portions 34, the translational mover 4, and the spring portions 42. Note that the depth of the first recess 58 can be set arbitrarily, but the depth of the portion facing the rotary mover 3 is set based on the rotation angle around the rotation axis O allowed for the rotary mover 3.

[0079] 4 and 6, a first fixed electrode 51 and a second fixed electrode 52 are arranged on the bottom surface of a first recess 58 of the lid portion 5. The first fixed electrode 51 is arranged at a position overlapping with the first rotatable electrode 314 when viewed from the thickness direction (Z direction). The second fixed electrode 52 is arranged at a position overlapping with the second rotatable electrode 321 when viewed from the thickness direction (Z direction). As shown in FIG. 6, a second recess 59 may be formed by further carving out the bottom surface of the first recess 58 at a position on the bottom surface of the first recess 58 that faces a portion (main body 311) of the first rotary movable element 31 other than the first rotatable electrode 314 and a portion of the second rotary movable element 32 other than the second rotatable electrode 321. As a result, even if the first rotating movable element 31 (first rotating movable electrode 314) is curved so that the bottom side of the first recess 58 is convex when the first rotating movable element 31 (first rotating movable electrode 314) moves (rotates) in a direction toward the first fixed electrode 51, the curved portion of the first rotating movable element 31 other than the first rotating movable electrode 314 enters the second recess 59, thereby reducing contact of the curved portion with the bottom surface of the first recess 58 (bottom surface of the second recess 59) and reducing poor contact between the first rotating movable electrode 314 and the first fixed electrode 51 (Figure 7). Similarly, even if the second rotary movable element 32 (second rotary movable electrode 321) is curved so that the bottom surface side of the first recess 58 is convex when the second rotary movable element 32 (second rotary movable electrode 321) moves (rotates) in a direction toward the second fixed electrode 52, the curved portion of the second rotary movable element 32 other than the second rotary movable electrode 321 fits into the second recess 59, thereby reducing contact of the curved portion with the bottom surface of the first recess 58 (bottom surface of the second recess 59) and reducing poor contact between the second rotary movable electrode 321 and the second fixed electrode 52 ( FIG. 8 ). Note that the second recess 59 can be formed by the same method (etching, sandblasting, etc.) as that for the first recess 58 after the first recess 58 is formed.

[0080] On the upper surface of the lid portion 5, a first external electrode 53, a second external electrode 54, a third external electrode 55, a fourth external electrode 56, and a fifth external electrode 57 are arranged.

[0081] The first external electrode 53 is disposed at a position overlapping the first fixed electrode 51 when viewed in the thickness direction. A through hole penetrating the lid 5 in the thickness direction is formed in the lid 5 at a position between the first external electrode 53 and the first fixed electrode 51, and the through hole is filled with a through electrode 531. The through electrode 531 is in contact with the first fixed electrode 51 and the first external electrode 53. Therefore, the first external electrode 53 is electrically connected to the first fixed electrode 51 via the through electrode 531.

[0082] The second external electrode 54 is disposed at a position overlapping the second fixed electrode 52 when viewed in the thickness direction. A through hole penetrating the lid 5 in the thickness direction is formed in the lid 5 at a position between the second external electrode 54 and the second fixed electrode 52, and the through hole is filled with a through electrode 541. The through electrode 541 is in contact with the second fixed electrode 52 and the second external electrode 54. Therefore, the second external electrode 54 is electrically connected to the second fixed electrode 52 via the through electrode 541.

[0083] The third external electrode 55 is disposed in a position overlapping with the portion of the frame 2 that will become the first connection electrode 21 (excluding the groove 27, which will be described later, and the portion that will become the second connection electrode 22). Furthermore, a through hole that penetrates the lid 5 in the thickness direction is formed in the position of the lid 5 where the third external electrode 55 is disposed, and this through hole is filled with a through electrode 551. The through electrode 551 is in contact with the frame 2 and the third external electrode 55. Therefore, the third external electrode 55 is electrically connected to the first connection electrode 21 via the through electrode 551.

[0084] The fourth external electrode 56 is disposed in a position on the frame 2 that overlaps with a portion that will become the second connection electrode 22 that corresponds to the translational mover 4X. Furthermore, a through hole that penetrates the lid 5 in the thickness direction is formed in the position of the lid 5 where the fourth external electrode 56 is disposed, and this through hole is filled with a through electrode 561. The through electrode 561 is in contact with the second connection electrode 22 and the fourth external electrode 56. Therefore, the fourth external electrode 56 is electrically connected via the through electrode 561 to the second connection electrode 22 that corresponds to the translational mover 4X.

[0085] The fifth external electrode 57 is disposed in a position on the frame 2 overlapping with a portion that will become the second connection electrode 22 corresponding to the translational mover 4Y. Furthermore, a through hole that penetrates the lid 5 in the thickness direction is formed in the position of the lid 5 where the fifth external electrode 57 is disposed, and this through hole is filled with a through electrode 571. The through electrode 571 is in contact with the second connection electrode 22 and the fifth external electrode 57. Therefore, the fifth external electrode 57 is electrically connected to the second connection electrode 22 corresponding to the translational mover 4Y via the through electrode 571.

[0086] [Operation of the rotary mover 3 and the beam portion 34] FIG. 6 is a cross-sectional view taken along line BB in FIGS. 2 to 4, showing the state of the rotary mover 3 before the shock sensor 300 receives an impact in the -Z direction, or the state of the rotary mover 3 before receiving an impact in the +Z direction. FIG. 7 is a cross-sectional view taken along line BB in FIGS. 2 to 4, showing the state of the rotary mover 3 when the shock sensor 300 receives an impact in the -Z direction. FIG. 8 is a cross-sectional view taken along line BB in FIGS. 2 to 4, showing the state of the rotary mover 3 when the shock sensor 300 receives an impact in the +Z direction. FIG. 9 is a cross-sectional view taken along line CC in FIGS. 2 to 4, showing the state of the beam portion 34 before the shock sensor 300 receives an impact in the -Z direction, or the state of the beam portion 34 before receiving an impact in the +Z direction. FIG. 10 is a cross-sectional view taken along line CC in FIGS. 2 to 4, showing the state of the beam portion 34 when the shock sensor 300 receives an impact in the -Z direction. FIG. 11 is a cross-sectional view taken along line CC in FIGS. 2 to 4, showing the state of the beam portion 34 when the shock sensor 300 receives an impact in the +Z direction.

[0087] 6, a first recess 58 is disposed above the rotary mover 3, and an internal space is formed below the rotary mover 3 by removing the silicon substrate 1a and the insulating layer 1b, allowing the rotary mover 3 to rotate around the shaft 33. The radial direction of the rotary mover 3 (a direction perpendicular to the rotation axis direction and connecting the rotation axis O (shaft 33) and the center of gravity G) is approximately parallel to the Y direction.

[0088] 7, when an impact (acceleration) in the -Z direction is applied to the impact sensor 300, the first rotating movable element 31 (first rotating movable electrode 314) moves in the +Z direction relative to the substrate 1 and the lid portion 5 due to inertial force around the center of gravity G, and the second rotating movable element 32 (second rotating movable electrode 321) moves in the -Z direction relative to the substrate 1 and the lid portion 5, and the first rotating movable electrode 314 comes into contact with the first fixed electrode 51. At this time, the bent portion 313 elastically deforms in the -Z direction relative to the main body 311 of the first rotating movable element 31, so that the contact time between the first rotating movable electrode 314 and the first fixed electrode 51 can be lengthened.

[0089] 8, when an impact (acceleration) in the +Z direction is applied to the impact sensor 300, the first rotating movable element 31 (first rotating movable electrode 314) moves in the -Z direction relative to the substrate 1 and the lid portion 5 due to inertial force around the center of gravity G, and the second rotating movable element 32 (second rotating movable electrode 321) moves in the +Z direction relative to the substrate 1 and the lid portion 5, and the second rotating movable electrode 321 comes into contact with the second fixed electrode 52. At this time, the tip side of the second rotating movable element 32, where the second rotating movable electrode 321 is located, elastically deforms in a manner such that it is displaced in the -Z direction relative to the connection position of the second rotating movable element 32 with the main body 311, and therefore the contact time between the second rotating movable electrode 321 and the second fixed electrode 52 can be lengthened.

[0090] Furthermore, by appropriately setting the position of the center of gravity G of the rotating movable element 3 and the radial lengths of the first rotating movable element 31 and the second rotating movable element 32, it is possible to set the minimum impact (acceleration) required for the first rotating movable electrode 314 to contact the first fixed electrode 51 to be the same as the minimum impact (acceleration) required for the second rotating movable electrode 321 to contact the second fixed electrode 52.

[0091] 9, a first recess 58 is disposed above the beam 34, and an internal space is formed below the beam 34 by removing the silicon substrate 1a and the insulating layer 1b. Therefore, the beam 34 is elastically deformable with the connection position with the frame 2 as a fixed end and the connection position with the first rotary movable element 31 as a movable end. The radial direction of the beam 34 is approximately parallel to the Y direction.

[0092] 10, when an impact (acceleration) in the -Z direction is applied to the impact sensor 300, the first rotary movable element 31 moves in the +Z direction relative to the substrate 1 and the lid portion 5 due to the inertial force. As a result, the beam portion 34 is elastically deformed such that the movable end is displaced in the +Z direction.

[0093] 11, when an impact (acceleration) in the +Z direction is applied to the impact sensor 300, the first rotary movable element 31 moves in the -Z direction relative to the substrate 1 and the lid portion 5 due to the inertial force. As a result, the beam portion 34 is elastically deformed such that the movable end is displaced in the -Z direction.

[0094] Therefore, when an impact is applied to the impact sensor 300 in the Z direction, the beam portion 34 applies a restoring force to the first rotary movable element 31. Therefore, even if a large impact (acceleration) is applied to the impact sensor 300, the impact can be alleviated by the restoring force of the beam portion 34.

[0095] 2 and 3, translational mover 4X and translational mover 4Y are arranged on substrate 1. Translational mover 4X is for detecting impact (acceleration) in the left-right direction (X direction), and translational mover 4Y is for detecting impact (acceleration) in the up-down direction (Y direction). Although the orientations of the two are orthogonal to each other, they have the same configuration, so translational mover 4X will be explained as an example.

[0096] [Configuration of translational mover 4] Fig. 12 is a partial detailed view of Fig. 2. In the frame 2, grooves are formed that penetrate the substrate 1 so as to form the outlines of the translational movable element 4 (second movable element) and the spring elements 42, leaving the connection positions between the spring elements 42 and the frame 2, and the translational movable element 4 is supported by the frame 2 via the spring elements 42.

[0097] The translational mover 4 (4X) is supported by the frame 2 via spring portions 42. A pair of spring portions 42 are arranged so as to sandwich the translational mover 4 (4X) from the left and right directions.

[0098] For example, when the shock sensor 300 receives a leftward shock (acceleration), an inertial force is generated by the mass of the translational mover 4 (4X), and the translational mover 4 (4X) is displaced rightward relative to the frame 2.

[0099] For example, when the shock sensor 300 receives a shock (acceleration) in the right direction, the translational mover 4 (4X) is displaced leftward relative to the frame 2 due to the inertial force.

[0100] The translationally movable electrode 41 (second movable electrode) is a part or the whole of the translationally movable element 4, and is electrically connected to the first connection electrode 21 via the spring portion .

[0101] The displacement direction (X direction) of the translational mover 4 (4X) is perpendicular to the displacement direction (Z direction) of the rotational mover 3. The spring portion 42 and the translational mover 4 are arranged at a position facing the first rotational mover 31 in a direction (Y direction) intersecting the displacement direction (X direction) of the translational mover 4 (4X) and facing the second rotational mover 32 in the displacement direction (X direction) of the translational mover 4.

[0102] As a result, the spring portion 42 and the translational movable element 4 (4X) are arranged in the L-shaped area formed by the first rotary movable element 31 and the second rotary movable element 32, so that the impact sensor 300, which independently detects impact (acceleration) in the thickness direction (Z direction) and impact in a direction perpendicular to the thickness direction (Z direction), can be made smaller in the surface direction.

[0103] A first member 221 (first convex portion) is arranged at a position facing the lower edge of the translational movable element 4 on the frame portion 2. Furthermore, a first concave portion 411 is arranged at a position facing the first member 221 on the translational movable element 4.

[0104] The first member 221 forms gaps in the vertical and horizontal directions with respect to the first recess 411, and at least a portion of the first member 221 is housed in the first recess 411 without contacting the first recess 411. Note that the first member 221 comes into contact with the translationally movable electrode 41 when it comes into contact with the translationally movable element 4.

[0105] A stopper 211 (second convex portion) is arranged at a position facing the upper edge of the translational mover 4 on the frame portion 2. Furthermore, a second concave portion 412 is arranged at a position facing the stopper 211 on the translational mover 4.

[0106] The stopper 211 forms gaps between itself and the second recess 412 in the vertical and horizontal directions, and at least a portion of the stopper 211 is housed in the second recess 412 in a state of not contacting the second recess 412.

[0107] Here, the left side surface of the first recess 411 and the left side surface of the second recess 412 are located at the same position in the left-right direction, and the right side surface of the first recess 411 and the right side surface of the second recess 412 are located at the same position in the left-right direction. That is, the left-right center of the first recess 411 and the left-right center of the second recess 412 are located at the same position in the left-right direction. Therefore, the translational mover 4 has an "H" shape with the vertical direction as the vertical direction. The translational mover 4 has a mirror-symmetric shape with respect to a line (dashed line S shown in FIG. 12) that is parallel to the up-down direction and passes through the left-right center of the translational mover 4 (i.e., the left-right center of the first recess 411 and the second recess 412). By making the translational movable element 4 "H" shaped in this way, vibrations in directions other than the direction sandwiched between the spring portions 42 (left and right directions) and rotations (vibrations) around the rotation axis perpendicular to the left and right directions and the up and down directions can be reduced, thereby reducing false detections by the impact sensor 300.

[0108] 12, the first member 221 and the stopper 211 are also arranged so as to be mirror symmetrical with respect to the dashed line S shown in Fig. 12, but the width of the stopper 211 in the left-right direction is formed to be narrower than the width of the first member 221 in the left-right direction. As a result, the gap (D2) between the stopper 211 and the second recess 412 is formed to be wider than the gap (D1) between the first member 221 and the first recess 411.

[0109] Alternatively, the first member 221 and the stopper 211 may be formed on the translational movable element 4, the first recess 411 may be formed on the frame portion 2 (second connection electrode 22), and the second recess 412 may be formed on the frame portion 2 (first connection electrode 21).

[0110] The spring portions 42 (spring portions 42L, 42R) are formed so that their rigidity (elasticity) against forces in the left-right direction is weaker than their rigidity (elasticity) against forces in the up-down direction, and are members that can selectively expand and contract in the left-right direction but whose expansion and contraction in the up-down direction is more strongly suppressed than that in the left-right direction. The spring portions 42 deform when subjected to a left-right inertial force from the translationally movable element 4, thereby generating a restoring force.

[0111] The left spring portion 42L is connected to the upper inner edge of the frame portion 2 in FIG. 12 and to the lower end portion of the left edge of the translational movable element 4.

[0112] The left-side spring portion 42L extends in the vertical direction in an area surrounded by the translational movable element 4, the lower inner edge of the frame portion 2 in Figure 12, the left inner edge of the frame portion 2 in Figure 12, and the upper inner edge of the frame portion 2, and is folded back at a position adjacent to the lower inner edge of the frame portion 2 and a position adjacent to the upper inner edge of the frame portion 2, thereby forming a zigzag fold structure in which the beam moves back and forth in the vertical direction multiple times between the lower inner edge of the frame portion 2 and the upper inner edge of the frame portion 2.

[0113] The right spring portion 42R is connected to the upper inner edge of the frame portion 2 and to the lower end of the right edge of the translational movable element 4.

[0114] The right-side spring portion 42R extends in the vertical direction in an area surrounded by the translational movable element 4, the upper inner edge of the frame portion 2, the right inner edge of the frame portion 2 in Figure 12, and the lower inner edge of the frame portion 2, and is folded back at a position adjacent to the lower inner edge of the frame portion 2 and at a position adjacent to the upper inner edge of the frame portion 2, thereby forming a zigzag fold structure in which the beam moves back and forth in the vertical direction multiple times between the lower inner edge of the frame portion 2 and the upper inner edge of the frame portion 2.

[0115] The frame 2 has a first slit 201, a second slit 202, and a third slit 203 formed therein.

[0116] The first slit 201 is an opening that is located below the first member 221 of the frame 2 and extends in the left-right direction, and is located adjacent to the lower inner edge of the frame 2. The left end of the first slit 201 extends to a position to the left of the left inner edge of the frame 2, and the right end of the first slit 201 extends to a position to the right of the right inner edge of the frame 2.

[0117] Due to this first slit 201, the portion including the lower inner edge of the frame 2 becomes the second member 222, and the second member 222 is integrated with the first member 221. In addition, the portion of the frame 2 below the first slit 201 forms the second connection electrode 22.

[0118] The second slit 202 is an opening that extends upward from the left end of the first slit 201 and extends partway upward adjacent to the left inner edge of the frame 2. Due to this second slit 202, the portion including the lower side of the left inner edge of the frame 2 becomes the third member 223, and the third member 223 supports the first member 221. In addition, the portion of the frame 2 above and to the left of the second slit 202 and surrounded by a groove 27 (described later) forms the second connection electrode 22.

[0119] The third slit 203 is an opening that extends upward from the right end of the first slit 201 and extends partway upward adjacent to the right inner edge of the frame 2. Due to this third slit 203, the portion including the lower side of the right inner edge of the frame 2 becomes the fourth member 224, and the fourth member 224 supports the first member 221. In addition, the portion of the frame 2 above and to the right of the third slit 203 and surrounded by a groove 27 (described later) forms the second connection electrode 22.

[0120] A groove 27 is arranged in the frame 2. The groove 27 is formed by removing the active layer 1c of the frame 2 to expose the insulating layer 1b, and insulates the first connection electrode 21 and the second connection electrode 22 from each other.

[0121] Here, when the shock sensor 300 receives an impact (acceleration) from the left or right direction, the first member 221 comes into contact with the translationally movable electrode 41 (first recess 411). The first member 221, the second member 222, the third member 223, and the fourth member 224 serve as buffer electrodes that reduce the impact received from the translationally movable element 4.

[0122] The third member 223 is an elastically deformable member with a fixed end at the connection position with the frame portion 2 (a position adjacent to the upper end of the second slit 202) and a movable end at the connection position with the left end of the second member 222.

[0123] The fourth member 224 is an elastically deformable member with a fixed end at a connection position with the frame 2 (a position adjacent to the upper end of the third slit 203) and a movable end at a connection position with the right end of the second member 222. The third member 223 and the fourth member 224 are formed to have the same or approximately the same length in the vertical direction.

[0124] The first member 221 is configured to be supported at both ends by the third member 223 and the fourth member 224, but either one of the third member 223 and the fourth member 224 may be omitted and the first member 221 may be configured to be supported at one end.

[0125] [Movement of translational mover 4] Fig. 13 shows the state when an impact is received from the X direction in the arrangement shown in Fig. 12 and the translational mover 4 comes into contact with the first member 221 (buffer electrode). Fig. 14 shows the state when an impact is received from the X direction in the arrangement shown in Fig. 12 and the translational mover 4 further presses the first member 221 (buffer electrode) from the state shown in Fig. 13, deforming the third member 223 and the fourth member 224 that support the first member 221 and the second member 222, causing the translational mover 4 to further displace together with the first member 221 (buffer electrode) and come into contact with the stopper 211. Here, the translational mover 4X will be described as an example, but the translational mover 4Y operates in a similar manner although its displacement direction is orthogonal to that of the translational mover 4X, and therefore a description of the translational mover 4Y will be omitted.

[0126] When the shock sensor 300 receives an impact (acceleration) from, for example, the right side, an inertial force that displaces the translational mover 4(4X) relative to the frame portion 2 in the right direction is generated in the translational mover 4(4X), compressing the right-side spring portion 42R in the left-right direction and expanding the left-side spring portion 42L in the left-right direction, as shown in Fig. 13. When the impact (acceleration) from the right side exceeds a predetermined magnitude (first threshold), the translational mover 4(4X) (first recessed portion 411, translational movable electrode 41) comes into contact with the first member 221 (buffer electrode), as shown in Fig. 13.

[0127] 14, when an impact greater than the first threshold is applied to the impact sensor 300 from the right, the translational mover 4(4X) (first recess 411) in contact with the first member 221 (buffer electrode) further presses the first member 221 (buffer electrode). As a result, the third member 223 and the fourth member 224 elastically deform in the pressing direction (rightward) of the translational mover 4(4X), and as a result, the first member 221 (buffer electrode) is displaced in the pressing direction (rightward) of the translational mover 4(4X) without changing its orientation. At this time, because the displacement of each movable end due to the elastic deformation of the third member 223 and the fourth member 224 is small, the first member 221 (buffer electrode) is displaced in parallel with the translational mover 4(4X) (translationally movable electrode 41).

[0128] When the impact (acceleration) from the right exceeds a predetermined magnitude (second threshold (a value greater than the first threshold)), the translational movable element 4 (4X) (second recess 412) comes into contact with the stopper 211, as shown in FIG. 14.

[0129] Conversely, although not shown in the figures, when the shock sensor 300 receives an impact from the left, an inertial force is generated in the translational movable element 4(4X) that displaces it leftward relative to the frame portion 2, compressing the left spring portion 42L in the left-right direction and expanding the right spring portion 42R in the left-right direction. When the impact (acceleration) from the left exceeds the first threshold value, the translational movable element 4(4X) (first recess 411, translational movable electrode 41) comes into contact with the first member 221 (buffer electrode).

[0130] When an impact greater than the first threshold is applied to the impact sensor 300 from the left, the translational mover 4(4X) (first recess 411) further presses the first member 221 (buffer electrode). This causes the third member 223 and the fourth member 224 to elastically deform in the pressing direction (leftward) of the translational mover 4(4X), and as a result, the first member 221 (buffer electrode) is displaced in the pressing direction (leftward) of the translational mover 4(4X) without changing its orientation. At this time, the displacement of each movable end due to the elastic deformation of the third member 223 and the fourth member 224 is small, so the first member 221 (buffer electrode) is displaced in parallel together with the translational mover 4(4X) (translationally movable electrode 41).

[0131] When the impact (acceleration) from the left exceeds a predetermined magnitude (second threshold (a value greater than the first threshold)), the translational mover 4 (4X) (second recess 412) comes into contact with the stopper 211.

[0132] It is preferable to set the first threshold value so that it is the same as the minimum impact (acceleration) required for the first rotating movable electrode 314 to contact the first fixed electrode 51 and the minimum impact (acceleration) required for the second rotating movable electrode 321 to contact the second fixed electrode 52.

[0133] [Layer structure of the impact sensor 300] 5 and other figures, the substrate 1 of the shock sensor 300 is formed of an SOI (Silicon On Insulator) wafer as described above. The SOI wafer is formed by laminating an insulating layer 1b (support layer) made of SiO2 (SiO2) and an active layer 1c (Si) in that order on a silicon substrate 1a (support layer).

[0134] In the manufacturing process of the substrate 1, for example, the silicon substrate 1a and the insulating layer 1b on the back surface of the SOI wafer are etched (e.g., dry etched) to match the outer shape of the frame portion 2, and the active layer 1c on the front surface of the SOI wafer is etched to match the outer shapes of the rotary movable element 3, the shaft portion 33, the beam portion 34, the translation movable element 4, and the spring portion 42, and the shape of the groove portion 27, and the portion of the surface of the SOI wafer where the active layer 1c remains is metal-plated to form the substrate 1.

[0135] Therefore, the surface of the substrate 1 (frame portion 2, rotary movable element 3, shaft portions 33, beam portions 34, translational movable element 4, spring portions 42) is covered with metal (e.g., copper) plating except for the groove portions 27. Therefore, the first rotary movable electrode 314 and the second rotary movable electrode 321 arranged on the rotary movable element 3 are electrically connected to each other. Furthermore, the first rotary movable electrode 314 and the second rotary movable electrode 321 are electrically connected to the first connection electrode 21 (frame portion 2) via the metal plating covering the shaft portions 33 and / or the metal plating covering the beam portions 34. Furthermore, the translational movable electrode 41 arranged on the translational movable element 4 is electrically connected to the second connection electrode 22 (frame portion 2) via the metal plating covering the spring portions 42. It is also possible to apply metal plating to the portions of the rotary movable element 3 where the first rotary movable electrode 314 and the second rotary movable electrode 321 are formed, and to arrange the linear metal plating connecting the first rotary movable electrode 314 and the first connecting electrode 21 so as to pass through the main body 311 and the shaft portion 33 (and / or the beam portion 34) of the first rotary movable element 31, and to arrange the linear metal plating connecting the second rotary movable electrode 321 and the first connecting electrode 21 so as to pass through the main body 311 and the shaft portion 33 (and / or the beam portion 34) of the first rotary movable element 31. It is also possible to omit the metal plating when the active layer 1c is, for example, a low-resistance silicon layer because the silicon layer becomes a conductor.

[0136] The first recess 58 of the lid portion 5 and the through holes for forming the through electrodes 531 etc. are formed by etching (e.g., dry etching) or sandblasting. The through electrodes 531 etc. are formed from a conductive paste, and the other electrodes are formed from a conductive paste or by sputtering.

[0137] Then, the substrate 1 (frame portion 2) and the lid portion 5 (portion other than the first recess portion 58) are joined by anodic bonding or conductive paste (adhesive).

[0138] Note that the beam width of the spring portion 42 is narrower than the thickness of the active layer 1c, but the thickness of the spring portion 42 is formed to be approximately the same as or the same as the thickness of the active layer 1c. This makes it difficult for the spring portion 42 to deform (elastically deform) in a direction (thickness direction) perpendicular to the left-right and up-down directions, and for example, when the impact sensor 300 is arranged horizontally, it is possible to reduce sinking of the translational movable element 4 in the thickness direction of the impact sensor 300.

[0139] [Modification of Substrate 1] Fig. 15 is a plan view of a first modified example of the substrate 1 of the impact sensor 300 according to this embodiment. Fig. 16 is a plan view of a second modified example of the substrate 1 of the impact sensor 300 according to this embodiment.

[0140] 15, a pair of shaft portions 33 are arranged so as to sandwich the first rotary mover 31 from the left and right. In this way, by forming the pair of shaft portions 33 so that the distance in the left and right direction is equal to or greater than the left and right direction of the first rotary mover 31, it is possible to suppress rotation (vibration) of the rotary mover 3 around the center of gravity G and the thickness direction (Z direction) as the rotation axis.

[0141] 16, beam portions 34 are arranged at both left and right ends of the first rotary movable element 31. By arranging the beam portions 34 at both left and right ends of the first rotary movable element 31 in this way, rotation of the rotary movable element 31 around the thickness direction (Z direction) as the rotation axis is suppressed.

[0142] When the rotating movable element 3 rotates (vibrates) around the center of gravity G with the thickness direction (Z direction) as the rotation axis, the vibration energy is converted into vibration energy that causes the rotating movable element 3 to rotate (vibrate) around the rotation axis O, which may be erroneously detected as an impact (acceleration) in the thickness direction (Z direction); however, by suppressing the rotation, such erroneous detection can be reduced.

[0143] [Electronic tag 100 including shock sensor 300] FIG. 17 is a schematic diagram of an electronic tag 100 including an impact sensor 300 according to this embodiment.

[0144] As shown in FIG. 17, the electronic tag 100 includes an impact sensor 300, a battery 400, a real-time clock (hereinafter referred to as RTC) 500, a latch circuit 600k (k=1 to 4), a control circuit 700, an antenna 800, and a memory 900.

[0145] The RTC 500, latch circuit 600k, control circuit 700, and memory 900 can each be provided as an IC (Integrated Circuit) chip. Also, some or all of these components may be mounted in a single IC package.

[0146] The electronic tag 100 is configured by housing a mounting board, on which the above-mentioned components are mounted, in a resin tag body 200. The mounting board may be a rigid board or a flexible board. The size of the electronic tag 100 is about several tens of millimeters in the longitudinal direction and about several millimeters in the thickness direction.

[0147] The battery 400 may be, for example, a button battery.

[0148] The RTC 500 has a clock function. The RTC 500 is electrically connected to the battery 400 so that power is constantly supplied to the RTC 500. The RTC 500 keeps time while power is being supplied to the RTC 500.

[0149] The impact sensor 300 is connected to four latch circuits 600k (k=1 to 4) by electric wires S1k and S2k (k=1 to 4), and is electrically connected to the battery 400 via the latch circuits 600k. In this embodiment, the path for supplying power from the battery 400 to the impact sensor 300 is incorporated in the latch circuit 600k.

[0150] The electric wire S1k (k=1) connected to the latch circuit 600k (k=1) is connected to the first external electrode 53, and the electric wire S2k (k=1) is connected to the third external electrode 55. Therefore, the latch circuit 600k (k=1) detects an impact (acceleration) in the -Z direction.

[0151] The electric wire S1k (k=1) connected to the latch circuit 600k (k=2) is connected to the second external electrode 54, and the electric wire S2k (k=1) is connected to the third external electrode 55. Therefore, the latch circuit 600k (k=2) detects an impact (acceleration) in the +Z direction.

[0152] The electric wire S1k (k=3) connected to the latch circuit 600k (k=3) is connected to the fourth external electrode 56, and the electric wire S2k (k=3) is connected to the third external electrode 55. Therefore, the latch circuit 600k (k=3) detects an impact (acceleration) in the X direction.

[0153] The electric wire S1k (k=4) connected to the latch circuit 600k (k=4) is connected to the fifth external electrode 57, and the electric wire S2k (k=4) is connected to the third external electrode 55. Therefore, the latch circuit 600k (k=4) detects an impact (acceleration) in the Y direction.

[0154] The shock sensor 300 is a mechanical sensor that is configured to conduct electricity when an impact (acceleration) equal to or greater than the minimum acceleration (the first threshold) is applied, and not conduct electricity when an impact (acceleration) equal to or greater than the minimum acceleration is not applied. The shock sensor 300 does not consume power from the battery 400 when an impact (acceleration) equal to or greater than the minimum acceleration is not applied.

[0155] The latch circuit 600 k is electrically connected to the battery 400 , the impact sensor 300 , and the control circuit 700 .

[0156] The latch circuit 600k detects the conduction between the electric wire S1k and the electric wire S2k.

[0157] When the electric wires S1k and S2k are energized, the latch circuit 600k enters an ON state in which it supplies power to the control circuit 700, and maintains the ON state even if the energization is subsequently interrupted. After that, when the latch circuit 600k receives a control signal (power OFF signal) from the control circuit 700, it enters an OFF state in which it does not supply power to the control circuit 700. In the OFF state, the latch circuit 600k does not consume power from the battery 400. The latch circuit 600k will be described in detail later.

[0158] The control circuit 700 is electrically connected to the RTC 500, the latch circuit 600k, the antenna 800, and the memory 900. When power is supplied from the latch circuit 600k to the control circuit 700, power is also supplied to the memory 900 via the control circuit 700. When the latch circuit 600k is turned on, power may be supplied directly from the latch circuit 600k to the memory 900.

[0159] When power is supplied from the latch circuit 600 k, the control circuit 700 acquires the time from the RTC 500 and writes the acquired time information into the memory 900 .

[0160] In the electronic tag 100, when an acceleration (impact) whose absolute value is greater than or equal to a predetermined acceleration (first threshold) is applied to the impact sensor 300, the impact sensor 300 becomes powered, and as a result, the latch circuit 600k supplies power to the control circuit 700, which then obtains from the RTC 500 the time when the acceleration (impact) was applied to the impact sensor 300.

[0161] For example, if there is a time lag between when an impact (acceleration) is applied to the impact sensor 300 and when the control circuit 700 obtains the time from the RTC 500 due to factors such as insufficient processing power of the control circuit 700, the time lag can be corrected by the control circuit 700, thereby essentially obtaining the time when the impact (acceleration) was applied to the impact sensor 300.

[0162] When the control circuit 700 has completed writing the time and the information regarding the number (k) of the latch circuit 600k that detected the impact (acceleration) to the memory 900, it outputs a control signal (power OFF signal) to the latch circuit 600k, causing the latch circuit 600k to enter an OFF state in which no power is supplied to the control circuit 700 and the memory 900. This stops the supply of power to the control circuit 700 and the memory 900. The control circuit 700 and the memory 900 do not consume power from the battery 400 when the latch circuit 600k is in the OFF state.

[0163] The memory 900 is a non-volatile memory that retains written contents even when power is not supplied.

[0164] The antenna 800 receives radio waves emitted from a reader / writer 920 (see FIG. 20 ) to generate power for operating the control circuit 700 and the memory 900. The control circuit 700 reads information written in the memory 900 using the power generated by the antenna 800, and sends the read information from the antenna 800 to the reader / writer 920.

[0165] It is also possible to rewrite the information stored in the memory 900 using the reader / writer 920. Note that non-rewritable information is also stored in the memory 900. The non-rewritable information is, for example, the identification information of the electronic tag 100.

[0166] In this way, the electronic tag 100 of this embodiment is configured as a wireless communication tag (RFID tag) compatible with RFID (Radio Frequency Identification) technology.

[0167] The electronic tag 100 may be a BLE tag that employs a BLUETOOTH (registered trademark) Low Energy (BLE) communication method, which is a low-power consumption communication mode.

[0168] [Latch circuit 600k] FIG. 18 is a circuit diagram showing an example of a latch circuit 600k that constitutes the electronic tag 100. As shown in FIG.

[0169] 18, the latch circuit 600k is an electronic circuit including a PNP transistor Tr1, an NPN transistor Tr2, a PNP transistor Tr3, an NPN transistor Tr4, resistors R1 to R11, and a capacitor C1. The latch circuit 600k is an electronic circuit that does not have any mechanically moving parts.

[0170] Resistors R1 and R2 form a series circuit, with one end of resistor R1 connected to a power supply (Vcc) and the other end connected to resistor R2. One end of resistor R2 is connected to resistor R1 and the other end is connected to electric wire S1k. Electric wire S2k is grounded.

[0171] The emitter of transistor Tr1 is connected to battery 400 (Vcc), the collector is connected to resistor R3, and the base is connected to the connection point between resistors R1 and R2. One end of resistor R3 is connected to the collector of transistor Tr1 and the other end is grounded.

[0172] Resistors R4, R7, and R8 form a series circuit. One end of resistor R4 is connected to the connection midpoint between transistor Tr1 (collector) and resistor R3, and the other end is connected to resistor R7. Resistor R7 has one end connected to resistor R4 and the other end connected to resistor R8 and the base of transistor Tr2. Resistor R8 has one end connected to resistor R7 and the base of transistor Tr2, and the other end grounded.

[0173] One end of the capacitor C1 is connected to the midpoint between the resistors R4 and R7, and the other end is grounded.

[0174] The collector of the transistor Tr2 is connected to a resistor R9, the base is connected to a resistor R7, and the emitter is grounded.

[0175] The transistor Tr3 has an emitter connected to the battery 400 (Vcc), a base connected to a resistor R9, and a collector connected to a resistor R11.

[0176] One end of the resistor R9 is connected to the base of the transistor Tr3, and the other end is connected to the collector of the transistor Tr2.

[0177] One end of the resistor R11 is connected to the collector of the transistor Tr3, and the other end is connected to the control circuit 700 (power supply input side).

[0178] The collector of the transistor Tr4 is connected to a resistor R6, the base is connected to a resistor R10, and the emitter is grounded.

[0179] One end of the resistor R6 is connected to the connection point between the resistors R4 and R7, and the other end is connected to the collector of the transistor Tr4.

[0180] One end of the resistor R10 is connected to the base of the transistor Tr4, and the other end is connected to the control circuit 700 (control signal output side).

[0181] One end of the resistor R5 is connected to the connection midpoint between the resistor R11 and the control circuit 700 (power supply input side), and the other end is connected to the connection midpoint between the resistor R4 and the resistor R7.

[0182] In the initial state (before acceleration is applied), the shock sensor 300 is not conducting, and the transistors Tr1 to Tr4 are in the OFF state (not conducting).

[0183] When the impact sensor 300 is energized, the voltage at the connection point between the resistors R1 and R2 drops, and the voltage at the base of the transistor Tr1 drops, causing the transistor Tr1 to turn on (energize).

[0184] When transistor Tr1 is turned on, a voltage is applied from transistor Tr1 to resistor R3 and the series circuit of resistors R4, R7, and R8, and the voltage at the connection midpoint of resistors R4 and R7 is applied to capacitor C1, and the voltage at the connection midpoint of resistors R7 and R8 is applied to the base of transistor Tr2.

[0185] Capacitor C1 is charged to the voltage at the junction of resistors R4 and R7.

[0186] A voltage at the midpoint of the connection between resistors R7 and R8 is applied to the base of transistor Tr2, and when the voltage drop across resistor R8, i.e., the voltage between the base and emitter of transistor Tr2, exceeds the threshold voltage (e.g., 0.6 V), transistor Tr2 turns ON.

[0187] When the transistor Tr2 is turned on, the base voltage of the transistor Tr3 drops, causing the transistor Tr3 to be turned on.

[0188] When transistor Tr3 is turned ON, power is supplied to the control circuit 700 (power input side) from the battery 400 (Vcc) connected to the emitter of transistor Tr3 via the collector of transistor Tr3 and resistor R11. At this time, the voltage at the connection point between resistor R11 and the control circuit 700 is applied to resistors R5, R7, and R8. Therefore, the voltage at the collector of transistor Tr3, which is applied to the connection point between resistors R7 and R8, becomes the base voltage of transistor Tr2. As a result, even if the impact sensor 300 is subsequently de-energized and transistor Tr1 is turned OFF, transistor Tr2 remains ON.

[0189] When a control signal (power OFF signal) is input from the control circuit 700 to the base of the transistor Tr4, the transistor Tr4 is turned on.

[0190] When transistor Tr4 is turned on, current flows through resistor R6 (which has a resistance value significantly smaller than that of resistor R5), causing the voltage applied to resistor R8, i.e., the voltage between the base and emitter of transistor Tr2, to become lower than the threshold voltage (e.g., 0.6 V), causing transistor Tr2 to turn off.

[0191] When the transistor Tr2 is turned off, the base current of the transistor Tr3 becomes zero, and the transistor Tr3 is turned off, thereby stopping the power supply to the control circuit 700.

[0192] As described above, when an impact (acceleration) equal to or greater than the minimum acceleration is applied, the impact sensor 300 enters a conducting state and conducts electricity, and when the absolute value of the applied acceleration subsequently decreases and falls below the minimum acceleration, the impact sensor 300 enters a non-conducting state and cuts off the conduction of electricity.

[0193] Therefore, if the electronic tag 100 is configured so that power is supplied to the control circuit 700 and memory 900 only while the impact sensor 300 is energized, there is a possibility that the supply of power to the control circuit 700 and memory 900 will be stopped before the control circuit 700 has finished writing the time to the memory 900. In this case, the time when the impact sensor 300 detected the impact cannot be recorded in the memory 900.

[0194] In contrast, in this embodiment, by providing the latch circuit 600k, the supply of power to the control circuit 700 and memory 900 is maintained until the control circuit 700 completes writing the time to the memory 900. After the control circuit 700 completes writing the time to the memory 900, the latch circuit 600k is turned off, thereby stopping power consumption by the latch circuit 600k, the control circuit 700, and the memory 900. This makes it possible to suppress consumption of the battery 400 while preventing the occurrence of a failure in which the impact sensor 300 is unable to record the time at which it detected an impact.

[0195] In this embodiment, the series circuit of resistors R1 and R2 that supplies power from the battery 400 to the impact sensor 300 constitutes part of the latch circuit 600k.

[0196] Therefore, when the impact sensor 300 detects an impact, it turns on and the latch circuit 600k activates, supplying power to the control circuit 700. In other words, the current flowing through the series circuit of resistors R1 and R2 functions as a detection signal indicating that the impact sensor 300 has detected an impact.

[0197] This eliminates the need to separately send a detection signal from the shock sensor 300 to the latch circuit 600k. Therefore, compared to when the latch circuit 600k is activated by separately sending a detection signal from the shock sensor 300 to the latch circuit 600k, the time lag between when the shock sensor 300 detects an impact and when the latch circuit 600k supplies power to the control circuit 700 can be reduced. This also reduces the time lag between when the control circuit 700 obtains the time from the RTC 500 and when the time stored in the memory 900 is more reliable. Furthermore, the time it takes for the latch circuit 600k to switch to the OFF state is reduced, thereby reducing power consumption of the battery 400.

[0198] [Operation procedure for electronic tag 100] FIG. 19 is a flowchart showing the operation flow of the electronic tag 100.

[0199] In step S01, an impact (acceleration) whose absolute value is equal to or greater than the minimum acceleration is applied to the electronic tag 100 (impact sensor 300).

[0200] In step S02, the impact sensor 300 is put into an energized state and energized.

[0201] In step S03, the latch circuit 600k (k=1 to 4) is turned on, and power is supplied to the control circuit 700 and memory 900 from the latch circuit 600k.

[0202] In step S04, the control circuit 700 acquires the time from the RTC 500.

[0203] In step S05, the control circuit 700 writes the acquired time into the memory 900.

[0204] In step S06, the control circuit 700 outputs a control signal (power OFF signal) to the latch circuit 600k.

[0205] In step S07, the latch circuit 600k is turned off, and the supply of power from the latch circuit 600k to the control circuit 700 and memory 900 is stopped.

[0206] [How to use the 100 electronic tags] FIG. 20 is a diagram for explaining how to use the electronic tag 100. In FIG.

[0207] In step (1), the electronic tag 100 is attached to a portable object 910. The portable object 910 is any of a variety of objects that can be transported and to which the electronic tag 100 can be attached.

[0208] The electronic tag 100 may be attached to the portable item 910 using, for example, double-sided tape, or may be attached to the portable item 910 using a dedicated jig, or may be attached to the portable item 910 by screwing an attachment hole into the tag body 200 (Figure 17).

[0209] In step (2), an impact is applied to the portable object 910 to which the electronic tag 100 is attached. The electronic tag 100 stores the time when the impact is detected by the impact sensor 300 in the memory 900. Fig. 20 shows how negative acceleration is applied to the portable object 910 due to a fall.

[0210] When the electronic tag 100 detects an impact multiple times, it stores in the memory 900 all of the times at which the impacts were detected.

[0211] In step (3), the information stored in the memory 900 is read using the reader / writer 920.

[0212] [Effects of this embodiment] The impact sensor 300 of this embodiment includes a stator (frame portion 2), a first mover (rotating mover 3) that is supported relative to the stator (frame portion 2) via a shaft portion 33 and is rotatable around the shaft portion 33 as a rotation axis O, first movable electrodes (first rotating movable electrode 314, second rotating movable electrode 321) arranged on the first mover (rotating mover 3), and fixed electrodes (first fixed electrode 51, second fixed electrode 52) arranged at positions facing the first movable electrodes (first rotating movable electrode 314, second rotating movable electrode 321). The first mover (rotating mover 3) is supported by the shaft portion 33 so that the center of gravity G of the first mover (rotating mover 3) is separated from the rotation axis O, and the first mover (rotating mover 3) is rotatable in the direction of the rotation axis of the first mover (rotating mover 3) and in a direction intersecting (perpendicular to) the rotation axis direction. The impact sensor 300 is displaceable in a manner that rotates around the rotation axis O when it receives an impact in a direction perpendicular to the radial direction connecting the axis O and the center of gravity G, and the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) is positioned at a position away from the rotation axis O, and detects an impact when the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) comes into contact with the fixed electrode (first fixed electrode 51, second fixed electrode 52) due to displacement of the first movable element (rotating movable element 3).The first movable element (rotating movable element 3) and the stator (frame portion 2) are connected by a beam portion 34 whose longitudinal direction is a direction intersecting (orthogonal to) the rotation axis direction, and the beam portion 34 is deformable (elastically deformable) in accordance with the displacement of the rotating movable element 3.

[0213] In the above configuration, the shaft portion 33 can suppress displacement of the first mover (rotating mover 3) due to impact (acceleration) in the rotation axis direction (X direction, left-right direction), but it is difficult to suppress displacement of the first mover (rotating mover 3) in a direction perpendicular to the rotation axis direction (Y direction, up-down direction). When this displacement occurs, the energy of the displacement is converted into energy that rotates the first mover (rotating mover 3) around the rotation axis O, and the first movable electrodes (first rotating movable electrode 314, second rotating movable electrode 321) come into contact with the fixed electrodes (first fixed electrode 51, second fixed electrode 52). In other words, there is a risk that impact (acceleration) in a direction other than the thickness direction (Z direction) will be detected as impact (acceleration) in the thickness direction (Z direction).

[0214] However, because the beam portion 34 is a member whose longitudinal direction is the direction (Y direction, up-down direction) perpendicular to the rotation axis direction (X direction, left-right direction), it can suppress displacement of the first mover (rotational mover 3) due to an impact (acceleration) in the direction (Y direction, up-down direction) perpendicular to the rotation axis direction. Therefore, by suppressing displacement of the first mover (rotational mover 3) due to an impact (acceleration) in the rotation axis direction (left-right direction) and the direction (up-down direction) perpendicular to the rotation axis direction, it is possible to reduce erroneous detection of an impact (acceleration) in a direction other than the thickness direction (Z direction) as an impact in the thickness direction (Z direction). Furthermore, when the first mover (rotational mover 3) is displaced in a manner to rotate around the rotation axis O, the beam portion 34 deforms (elastically deforms) in accordance with the displacement, and can therefore apply a restoring force to the first mover (rotational mover 3). Therefore, even if a large impact (acceleration) is applied from the thickness direction (Z direction), the restoring force reduces the displacement and displacement speed of the first movable element (rotating movable element 3), thereby reducing damage to the first movable element (rotating movable element 3).

[0215] In this embodiment, the first movable element (rotating movable element 3) includes a first rotating movable element 31 including the center of gravity G, and a second rotating movable element 32 extending from the first rotating movable element 31 on the opposite side of the rotation axis O of the center of gravity G, and the beam portion 34 connects the first rotating movable element 31 and the stator (frame portion 2) and is deformable (elastically deformable) in accordance with the displacement of the first rotating movable element 31.

[0216] With the above configuration, it is possible to individually detect impacts (accelerations) in both directions in the thickness direction (±Z directions). Furthermore, because the beam portions 34 are deformable (elastically deformable) in both directions in the thickness direction (±Z directions), even if a large impact (acceleration) is applied from either direction in the thickness direction (Z direction), the restoring force of the beam portions 34 reduces the displacement and displacement speed of the rotary movable element 3, thereby reducing damage to the rotary movable element 3.

[0217] In this embodiment, the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) includes a first rotating movable electrode 314 arranged on the first rotating movable element 31, and the fixed electrodes (first fixed electrode 51, second fixed electrode 52) include a first fixed electrode 51 arranged at a position opposite to the first rotating movable electrode 314, and when the first rotating movable electrode 314 is displaced toward the first fixed electrode 51, the first rotating movable electrode 314 comes into contact with the first fixed electrode 51.

[0218] With the above configuration, an impact in the direction in the thickness direction in which the first rotating movable electrode 314 (first rotating movable element 31) moves toward the first fixed electrode 51 can be detected by contact between the first rotating movable electrode 314 and the first fixed electrode 51, resulting in an impact sensor 300 that can detect an impact from one direction in the thickness direction with a simple configuration.

[0219] In this embodiment, the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) includes a second rotating movable electrode 321 arranged on the second rotating movable element 32, and the fixed electrodes (first fixed electrode 51, second fixed electrode 52) include a second fixed electrode 52 arranged at a position opposite to the second rotating movable electrode 321, and when the second rotating movable electrode 321 is displaced toward the second fixed electrode 52, the second rotating movable electrode 321 comes into contact with the second fixed electrode 52.

[0220] With the above configuration, an impact in the direction in the thickness direction in which the first rotating movable electrode 314 (first rotating movable element 31) moves away from the first fixed electrode 51, i.e., an impact in the direction in which the second rotating movable electrode 321 (second rotating movable element 32) moves toward the second fixed electrode 52, can be detected by contact between the second rotating movable electrode 321 and the second fixed electrode 52, resulting in an impact sensor 300 that can detect an impact from the other direction in the thickness direction with a simple configuration.

[0221] In this embodiment, the first movable electrodes (first rotating movable electrode 314, second rotating movable electrode 321) include a first rotating movable electrode 314 arranged on the first rotating movable element 31 and a second rotating movable electrode 321 arranged on the second rotating movable element 32, and the fixed electrodes (first fixed electrode 51, second fixed electrode 52) include a first fixed electrode 51 arranged at a position opposite the first rotating movable electrode 314 and a second fixed electrode 52 arranged at a position opposite the second rotating movable electrode 321, and when the first rotating movable electrode 314 displaces toward the first fixed electrode 51, the first rotating movable electrode 314 comes into contact with the first fixed electrode 51 and the second rotating movable electrode 321 moves away from the second fixed electrode 52, and when the second rotating movable electrode 321 displaces toward the second fixed electrode 52, the first rotating movable electrode 314 moves away from the first fixed electrode 51 and the second rotating movable electrode 321 comes into contact with the second fixed electrode 52.

[0222] With the above configuration, the first rotating movable electrode 314 (first rotating movable element 31) detects an impact in the direction toward the first fixed electrode 51 in the thickness direction by contact between the first rotating movable electrode 314 and the first fixed electrode 51, and the second rotating movable electrode 321 is positioned away from the second fixed electrode 52, and the second rotating movable electrode 321 (second rotating movable element 32) detects an impact in the direction toward the second fixed electrode 52 in the thickness direction by contact between the second rotating movable electrode 321 and the second fixed electrode 52, and the first rotating movable electrode 314 is positioned away from the first fixed electrode 51, resulting in an impact sensor 300 with a simple configuration that can individually detect impacts in both directions in the thickness direction without erroneous detection.

[0223] In this embodiment, both longitudinal ends of the beam portion 34 are disposed so as to sandwich the rotation axis O when viewed from the rotation axis direction.

[0224] With the above configuration, when the first mover (rotary mover 3) rotates around the rotation axis O, the beam portion 34 is reliably deformed (elastically deformed) and a restoring force can be generated in the beam portion 34.

[0225] In this embodiment, the width of the beam portion 34 in the rotation axis direction becomes narrower from the stator (frame portion 2) toward the first mover (rotating mover 3) (first rotating mover 31).

[0226] With the above configuration, when the first movable element (rotating movable element 3) rotates around the rotation axis O, the beam portion 34 can be deformed (elastically deformed) approximately uniformly throughout the entire longitudinal direction, thereby reducing stress concentration at specific locations (especially the connection position of the beam portion 34 with the stator (frame portion 2)) and increasing the durability of the beam portion 34.

[0227] In this embodiment, the width of the second rotating movable element 32 in the rotational axis direction is narrower than the width of the first rotating movable element 31 in the rotational axis direction, the beam portions 34 are arranged in a pair so as to sandwich the second rotating movable element 32 from the rotational axis direction, and the shaft portions 33 are arranged in a pair so as to sandwich the pair of beam portions 34 from the rotational axis direction and are connected to the first rotating movable element 31.

[0228] With the above configuration, it is possible to reduce the area occupied by the integral body of the first mover (rotary mover 3), shaft portion 33, and beam portion 34, thereby miniaturizing the impact sensor 300 in the planar direction. Furthermore, since the distance between the pair of shaft portions 33 is longer than the distance between the pair of beam portions 34, the pair of shaft portions 33 suppress rotation about the thickness direction (Z direction) of the first mover (rotary mover 3) as the rotation axis, and it is possible to reduce erroneous detection of impacts caused by such rotation.

[0229] In this embodiment, the width of the second rotating movable element 32 in the rotational axis direction is narrower than the width of the first rotating movable element 31 in the rotational axis direction, the shaft portions 33 are arranged in a pair so as to sandwich the second rotating movable element 32 from the rotational axis direction, and the beam portions 34 are arranged in a pair so as to sandwich the pair of shaft portions 33 from the rotational axis direction.

[0230] With the above configuration, it is possible to reduce the area occupied by the integral body of the first mover (rotary mover 3), shaft portion 33, and beam portion 34, thereby miniaturizing the impact sensor 300 in the planar direction. Furthermore, since the distance between the pair of shaft portions 33 is longer than the distance between the pair of beam portions 34, the pair of shaft portions 33 suppress rotation about the thickness direction (Z direction) of the first mover (rotary mover 3) as the rotation axis, and it is possible to reduce erroneous detection of impacts caused by such rotation.

[0231] In this embodiment, the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) includes a first rotating movable electrode 314 arranged on the first rotating movable element 31 and a second rotating movable electrode 321 arranged on the second rotating movable element 32, and the first rotating movable electrode 314 and the second rotating movable electrode 321 are arranged at a position between a pair of beam portions 34 in the rotation axis direction.

[0232] With the above configuration, the first movable element (rotating movable element 3) can be formed in a shape that is perpendicular to the rotation axis direction and mirror-symmetrical about the line connecting the rotation axis O and the center of gravity G, thereby reducing unnecessary vibration components of the first movable element (rotating movable element 3) that may occur when the impact sensor 300 receives an impact (acceleration), and reducing false detection of impact due to these unnecessary vibration components.

[0233] In this embodiment, the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) includes a first rotating movable electrode 314 arranged on the first rotating movable element 31 and a second rotating movable electrode 321 arranged on the second rotating movable element 32, and the first rotating movable electrode 314 and the second rotating movable electrode 321 are arranged at a position between a pair of shaft portions 33 in the rotation axis direction.

[0234] With the above configuration, the first movable element (rotating movable element 3) can be formed in a shape that is perpendicular to the rotation axis direction and mirror-symmetrical about the line connecting the rotation axis O and the center of gravity G, thereby reducing unnecessary vibration components of the first movable element (rotating movable element 3) that may occur when the impact sensor 300 receives an impact (acceleration), and reducing false detection of impact due to these unnecessary vibration components.

[0235] In this embodiment, the width of the second rotary mover 32 in the rotation axis direction becomes narrower as it moves away from the first rotary mover 31.

[0236] With the above configuration, when the second rotating movable electrode 321 (second rotating movable element 32) comes into contact with the second fixed electrode 52 (cover portion 5), the second rotating movable element 32 can be deformed (elastically deformed) approximately uniformly in its longitudinal direction, thereby reducing stress concentration at specific parts of the second rotating movable element 32 (particularly the connection position of the second rotating movable element 32 with the first rotating movable element 31 (main body 311)) and increasing the durability of the second rotating movable element 32.

[0237] Furthermore, when the impact sensor 300 receives an impact (acceleration) and the contact time between the second rotating movable electrode 321 and the second fixed electrode 52 is short, the circuit that detects the contact (latch circuit 600k) must be set to respond at a high frequency. However, in this case, noise is likely to be mistakenly detected as an impact signal, and it is also difficult to keep the power consumption of the circuit (latch circuit 600k) low.

[0238] However, deformation (elastic deformation) of the second rotary movable element 32 can lengthen the contact time between the second rotary movable electrode 321 and the second fixed electrode 52. This makes it possible to set the circuit (latch circuit 600k) that detects contact between the second rotary movable electrode 321 and the second fixed electrode 52 to respond at a low frequency. This reduces the frequency of false detection of noise as an impact signal, and also makes it possible to keep the power consumption of this circuit (latch circuit 600k) low.

[0239] In this embodiment, the second rotary element 32 is provided with a slit 35 extending in the radial direction.

[0240] With the above configuration, the position of the center of gravity G of the first mover (rotary mover 3) can be set to a desired position.

[0241] In this embodiment, a pair of shaft portions 33 are arranged to sandwich the first mover (rotary mover 3) in the direction of the rotation axis.

[0242] With the above configuration, the first mover (rotary mover 3) can be rotated around the rotation axis O in a stable manner.

[0243] In this embodiment, the specific portion (bent portion 313) of the first rotating movable element 31 where the first rotating movable electrode 314 is arranged is set to have lower rigidity than the other portions of the first rotating movable element 31 other than the specific portion (bent portion 313).

[0244] The above configuration can lengthen the contact time between the first rotary movable electrode 314 and the first fixed electrode 51. This allows the circuit (latch circuit 600k) that detects contact between the first rotary movable electrode 314 and the first fixed electrode 51 to be set to respond at a low frequency. This reduces the frequency of falsely detecting noise as an impact signal, and also makes it possible to keep the power consumption of this circuit (latch circuit 600k) low.

[0245] In this embodiment, the first movable electrode (first rotating movable electrode 314, second rotating movable electrode 321) includes a first rotating movable electrode 314 arranged on the first rotating movable element 31 and a second rotating movable electrode 321 arranged on the second rotating movable element 32, and the fixed electrode (first fixed electrode 51, second fixed electrode 52) includes a first fixed electrode 51 arranged at a position opposite to the first rotating movable electrode 314 and a second fixed electrode 52 arranged at a position opposite to the second rotating movable electrode 321, and the lid portion 5 is bonded (laminated) to the stator (frame portion 2, active layer 1c of substrate 1), and the first fixed electrode 51 and second fixed electrode 52 are arranged on the main surface of the lid portion 5 facing the stator (frame portion 2, active layer 1c of substrate 1).

[0246] With the above configuration, the first fixed electrode 51 and the second fixed electrode 52 can be arranged with a simple configuration.

[0247] In this embodiment, the stator (frame portion 2), shaft portion 33, first movable element (rotating movable element 3), and beam portion 34 are an integral body, and the integral body is formed from a laminate in which an active layer 1c is stacked on a support layer (silicon substrate 1a, insulating layer 1b). The portion relating to the stator (frame portion 2) of the integral body is formed from the laminate, and the portion relating to the shaft portion 33, first movable element (rotating movable element 3), and beam portion 34 of the integral body is formed from the active layer 1c obtained by removing the support layer (silicon substrate 1a, insulating layer 1b) from the laminate.

[0248] With the above configuration, the impact sensor 300 can be formed by etching the stacked body (SOI wafer), and the impact sensor 300 can be easily manufactured in large quantities.

[0249] In this embodiment, the stator (frame portion 2) further includes a second movable element (translational movable element 4) supported by the stator (frame portion 2) via an elastic body (spring portion 42), and a second movable electrode (translational movable electrode 41) arranged on the second movable element (translational movable element 4), and the stator (frame portion 2) includes a first connection electrode 21 electrically connected to the first movable electrode (first rotational movable electrode 314, second rotational movable electrode 321) via the shaft portion 33 and / or the beam portion 34, and a second connection electrode 22 electrically connected to the second movable electrode (translational movable electrode 41) via the elastic body (spring portion 42) and arranged so as to be insulated from the first connection electrode 21, and the displacement direction of the second movable element (translational movable element 4) is perpendicular to the displacement direction of the first movable element (rotational movable element 3).

[0250] The above configuration provides the impact sensor 300 that can independently detect an impact (acceleration) in the thickness direction (Z direction) and an impact in a direction perpendicular to the thickness direction (Z direction).

[0251] In this embodiment, the stator (frame portion 2) further includes a second movable element (translational movable element 4) supported by the stator (frame portion 2) via an elastic body (spring portion 42), and a second movable electrode (translational movable electrode 41) arranged on the second movable element (translational movable element 4), and the stator (frame portion 2) includes a first connection electrode 21 electrically connected to the first movable electrode (first rotational movable electrode 314, second rotational movable electrode 321) via the shaft portion 33 and / or the beam portion 34, and a second connection electrode 21 electrically connected to the second movable electrode (translational movable electrode 41) via the elastic body (spring portion 42). and a second connection electrode 22 arranged so as to be electrically connected to the first connection electrode 21 and insulated from the first connection electrode 21, the displacement direction of the second movable element (translation movable element 4) is perpendicular to the displacement direction of the first movable element (rotation movable element 3), and the elastic body (spring portion 42) and the second movable element (translation movable element 4) are arranged at a position facing the first rotation movable element 31 in a direction intersecting (perpendicular to) the displacement direction of the second movable element (translation movable element 4) and facing the second rotation movable element 32 in the displacement direction of the second movable element (translation movable element 4).

[0252] With the above configuration, the elastic body (spring portion 42) and the second movable element (translational movable element 4) are arranged in the L-shaped area formed by the first rotary movable element 31 and the second rotary movable element 32, so that the impact sensor 300, which independently detects an impact (acceleration) in the thickness direction (Z direction) and an impact in a direction perpendicular to the thickness direction (Z direction), can be made smaller in the surface direction.

[0253] Although the present embodiment has been described above, the above embodiment merely shows one application example of the present invention, and is not intended to limit the technical scope of the present invention to the specific configuration of the above embodiment. [Explanation of symbols]

[0254] 300 Impact Sensor 1 board 1a Silicon substrate 1b Insulating layer 1c active layer 2 Frame 21 First connection electrode 211 Stopper 22 Second connection electrode 221 First member 222 Second member 223 Third member 224 Fourth member 225 5th member 27 Groove 201 First Slit 202 Second slit 203 Third Slit 3 Rotating element 31 First rotor 311 Main Unit 312 Arm 313 Bend 314 First rotating movable electrode 32 Second rotor 321 Second rotating movable electrode 33 Shaft 34 Beam section 35 Slit 4 4X 4Y Translation mover 41 Translationally movable electrode 411 First recess 412 Second recess 42 Spring part 5 Lid 51 1st fixed electrode 52 Second fixed electrode 53 1st external electrode 531 Through electrode 54 2nd external electrode 541 Through electrode 55 Third external electrode 551 Through electrode 56 4th external electrode 561 Through electrode 57 5th external electrode 571 Through electrode 58 First recess 59 Second recess 100 Electronic Tags 200 Tag Body 300 Impact Sensor 400 batteries 500 RTC 600 Latch Circuit 700 Control Circuit 800 Antenna 900 memory 910 Transportable items 920 Reader / Writer

Claims

1. A stator; a first mover supported by the stator via a shaft portion and rotatable about the shaft portion as a rotation axis; a first movable electrode disposed on the first movable element; a fixed electrode disposed at a position facing the first movable electrode, the first mover is supported by the shaft portion such that the center of gravity of the first mover is spaced apart from the rotation axis, and is displaceable in a manner of rotating about the rotation axis by receiving an impact in a direction perpendicular to the rotation axis direction of the first mover and a radial direction connecting the rotation axis and the center of gravity among directions intersecting the rotation axis direction, the first movable electrode is disposed at a position spaced apart from the rotation axis, an impact sensor that detects the impact by contact between the first movable electrode and the fixed electrode due to displacement of the first movable element, the first mover and the stator are connected by a beam portion whose longitudinal direction is a direction intersecting the rotation axis direction, The beam portion is deformable in accordance with the displacement of the first mover.

2. The first mover is a first rotary movable element including the center of gravity; a second rotary movable element extending from the first rotary movable element to an opposite side of the center of gravity across the rotation axis, 2. The impact sensor according to claim 1, wherein the beam portion connects the first rotary movable element and the stator, and is deformable in accordance with displacement of the first rotary movable element.

3. The first movable electrode is a first rotary movable electrode disposed on the first rotary movable element; The fixed electrode is a first fixed electrode disposed at a position facing the first rotary movable electrode; 3. The impact sensor according to claim 2, wherein the first rotary movable electrode comes into contact with the first fixed electrode when the first rotary movable electrode is displaced toward the first fixed electrode.

4. The first movable electrode is a second rotary movable electrode disposed on the second rotary movable element; The fixed electrode is a second fixed electrode disposed at a position facing the second rotary movable electrode; 3. The impact sensor according to claim 2, wherein the second rotary movable electrode comes into contact with the second fixed electrode when the second rotary movable electrode is displaced toward the second fixed electrode.

5. The first movable electrode is a first rotary movable electrode disposed on the first rotary movable element; a second rotary movable electrode disposed on the second rotary movable element, The fixed electrode is a first fixed electrode disposed at a position facing the first rotary movable electrode; a second fixed electrode disposed at a position facing the second rotary movable electrode, when the first rotating movable electrode is displaced toward the first fixed electrode, the first rotating movable electrode comes into contact with the first fixed electrode, and the second rotating movable electrode moves away from the second fixed electrode; 3. The impact sensor according to claim 2, wherein when the second rotating movable electrode is displaced toward the second fixed electrode, the first rotating movable electrode is separated from the first fixed electrode and the second rotating movable electrode is brought into contact with the second fixed electrode.

6. 3. The impact sensor according to claim 1, wherein both ends of the beam portion in the longitudinal direction are disposed so as to sandwich the rotation axis when viewed from the direction of the rotation axis.

7. 3. The impact sensor according to claim 1, wherein the width of the beam portion in the rotation axis direction narrows from the stator toward the first movable element.

8. a width of the second rotary movable element in the rotation axis direction is narrower than a width of the first rotary movable element in the rotation axis direction, the beam portions are arranged in pair to sandwich the second rotary movable element in the rotation axis direction, The shaft portion is 3. The impact sensor according to claim 2, wherein a pair of the beam portions are disposed on either side of the pair of beam portions in the rotation axis direction and are connected to the first rotary movable element.

9. a width of the second rotary movable element in the rotation axis direction is narrower than a width of the first rotary movable element in the rotation axis direction, the shaft portions are arranged in pair to sandwich the second rotary movable element in the rotation axis direction, The beam portion is 3. The impact sensor according to claim 2, wherein a pair of the shaft portions are disposed on either side of the pair of shaft portions in the direction of the rotation axis.

10. The first movable electrode is a first rotary movable electrode disposed on the first rotary movable element; a second rotary movable electrode disposed on the second rotary movable element, 9. The impact sensor according to claim 8, wherein the first rotary movable electrode and the second rotary movable electrode are disposed between the pair of beam portions in the direction of the rotation axis.

11. The first movable electrode is a first rotary movable electrode disposed on the first rotary movable element; a second rotary movable electrode disposed on the second rotary movable element, 10. The impact sensor according to claim 9, wherein the first rotary movable electrode and the second rotary movable electrode are disposed between the pair of shaft portions in the direction of the rotation axis.

12. 10. The impact sensor according to claim 8, wherein the width of the second rotary movable element in the rotation axis direction becomes narrower as the second rotary movable element becomes farther away from the first rotary movable element.

13. 10. The impact sensor according to claim 8, wherein the second rotary element has a slit extending in the radial direction.

14. 3. The impact sensor according to claim 1, wherein the shaft portions are arranged in a pair so as to sandwich the first mover in the direction of the rotation axis.

15. 4. The impact sensor according to claim 3, wherein a specific portion of the first rotary movable piece where the first rotary movable electrode is arranged is set to have lower rigidity than other portions of the first rotary movable piece.

16. The first movable electrode is a first rotary movable electrode disposed on the first rotary movable element; a second rotary movable electrode disposed on the second rotary movable element, The fixed electrode is a first fixed electrode disposed at a position facing the first rotary movable electrode; a second fixed electrode disposed at a position facing the second rotary movable electrode, 3. The impact sensor according to claim 2, wherein a lid is joined to the stator, and the first fixed electrode and the second fixed electrode are disposed on a main surface of the lid facing the stator.

17. the stator, the shaft portion, the first movable element, and the beam portion are an integral body, and the integral body is formed from a laminate in which an active layer is laminated on a support layer, a portion of the integrated body relating to the stator is formed by the laminated body, 3. The impact sensor according to claim 1, wherein the shaft portion, the first movable element, and the beam portion of the integrated body are formed from the active layer obtained by removing the support layer from the laminate.

18. a second movable element supported on the stator via an elastic body; a second movable electrode disposed on the second movable element, the stator includes a first connection electrode electrically connected to the first movable electrode via the shaft portion and / or the beam portion; a second connection electrode electrically connected to the second movable electrode via the elastic body and arranged so as to be insulated from the first connection electrode; 3. The impact sensor according to claim 1, wherein the displacement direction of the second mover is perpendicular to the displacement direction of the first mover.

19. a second movable element supported on the stator via an elastic body; a second movable electrode disposed on the second movable element, the stator includes a first connection electrode electrically connected to the first movable electrode via the shaft portion and / or the beam portion; a second connection electrode electrically connected to the second movable electrode via the elastic body and arranged so as to be insulated from the first connection electrode; a displacement direction of the second mover is perpendicular to a displacement direction of the first mover, 10. The impact sensor according to claim 8, wherein the elastic body and the second movable element are arranged in a position facing the first rotary movable element in a direction intersecting the displacement direction of the second movable element and facing the second rotary movable element in the displacement direction of the second movable element.

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