JP6169947B2 - Vibration sensor - Google Patents

Description

  The present invention relates to a vibration sensor.

  2. Description of the Related Art In recent years, a sensor that detects an inclination or a vibration state using an electrical contact between a rollable conductive spherical electrode and a fixed electrode, and a so-called ball sensor are known (for example, see Patent Document 1).

JP 2009-238715 A

  The ball sensor disclosed in Patent Document 1 has a ceramic structure in which a plurality of ceramic layers are stacked, and a fixed electrode penetrating a part of the ceramic structure is embedded in a part of the ceramic structure. The fixed electrode has a hole in a part of the ceramic structure, and a part of the hole is buried in the hole. The fixed electrode needs to be rigid enough to withstand contact with the conductive spherical electrode. Therefore, the fixed electrode needs to have a predetermined thickness and size. However, the fixed electrode is made of a metal material, and the ball sensor may be destroyed due to a difference in thermal expansion coefficient from the surrounding material.

  The present invention has been made in view of the above, and an object thereof is to provide a vibration sensor that is not easily destroyed.

A vibration sensor according to an embodiment of the present invention includes a substrate having a concave portion on an upper surface, a conductive member provided in the concave portion, and a frame-shaped conductive member provided on the substrate and surrounding the conductive member. A spherical conductive member provided on the substrate and in contact with the conductive member in a region surrounded by the frame-shaped conductive member, a frame provided on the substrate and surrounding the frame-shaped member, and the frame And a lid that covers the spherical conductive member. The conductive plate is provided to be spaced from the inner wall surface of the recess.

  ADVANTAGE OF THE INVENTION According to this invention, the vibration sensor which is hard to be destroyed can be provided.

It is a perspective view which shows the external appearance of the vibration sensor which concerns on this embodiment. It is a perspective view which shows the state which removed the cover body from the vibration sensor which concerns on this embodiment. It is a perspective view which shows the cross section of the vibration sensor along XX of FIG. It is sectional drawing of the vibration sensor shown in FIG. It is A arrow directional view of FIG. It is a B arrow view of FIG. It is a bottom view which shows the lower surface of the vibration sensor which concerns on this embodiment.

  Embodiments of a vibration sensor according to the present invention will be described below with reference to the accompanying drawings. In addition, this invention shall not be limited to the following embodiment.

<Schematic configuration of vibration sensor>
FIG. 1 is a schematic perspective view of the vibration sensor according to the present embodiment, showing a state in which a lid is attached. FIG. 2 is an external perspective view of the vibration sensor according to the present embodiment, and shows a state where the inside can be seen by removing the lid. In addition, the dashed-dotted line of FIG. 2 has shown the wiring conductor in a frame or a board | substrate. FIG. 3 is an external perspective view showing a cross section of the vibration sensor along the line XX in FIG. 1. FIG. 4 is a cross-sectional view of the vibration sensor along the line XX in FIG. FIG. 5 is a view taken in the direction of arrow A in FIG. 4 and shows a state where the lid of the vibration sensor is removed. FIG. 6 is a view taken in the direction of arrow B in FIG. 4 and shows the upper surface of the substrate. In addition, the dashed-dotted line of FIG. 6 has shown the location where a frame-shaped electrically-conductive member is mounted. FIG. 7 is a bottom view showing the bottom surface of the vibration sensor according to the present embodiment.

  A vibration sensor is incorporated in home appliances, electronic devices, and the like to detect inclination and vibration of those products. Examples of home appliances and electronic devices are digital cameras, mobile phones, smartphones, and the like. The vibration sensor can change the operation of various home appliances and electronic devices in accordance with a change in the conduction state of the vibration sensor.

  The vibration sensor 1 according to the present embodiment includes a substrate 2 having a concave portion P on the upper surface, a conductive plate 3 provided in the concave portion P, and a frame-like conductive material provided on the substrate 2 and surrounding the conductive plate 3. A member 4, a spherical conductive member 5 provided on the substrate 2 and in contact with the conductive plate 3 in a region surrounded by the frame-shaped conductive member 4, and a frame 6 provided on the substrate 2 and surrounding the frame-shaped conductive member 4. And a lid body 7 provided on the frame body 6 and covering the spherical conductive member 5.

  The substrate 2 is an insulating substrate and is made of, for example, a ceramic material such as alumina, mullite, or aluminum nitride, or a glass ceramic material. Or it consists of a composite material which mixed several materials among these materials. In addition, the board | substrate 2 is a rectangular external shape in planar view, Comprising: The length of one side is set to 1 mm or more and 10 mm or less. The thickness of the substrate 2 is set to 0.3 mm or more and 3 mm or less. The thermal conductivity of the substrate 2 is set to 14 W / m · K or more and 200 W / m · K or less. The thermal expansion coefficient of the substrate 2 is set to 4 ppm / K or more and 8 ppm / K or less.

  Further, the recess P formed on the upper surface of the substrate 2 has a size for accommodating the conductive plate 3. The recess P is provided in the central portion of the upper surface of the substrate 2. The concave portion P has a circular shape in plan view, and has a diameter of 0.5 mm or more and 8 mm or less. The depth of the concave portion P is set to 0.5 mm or more and 5 mm or less.

  The conductive plate 3 is received in the recess P. The conductive plate 3 is electrically connected to the spherical conductive member 5. The conductive plate 3 is a conductive disc, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold or aluminum, or an alloy thereof, or a mixture of a plurality of these materials. Composite material or a composite layer of these materials. The thermal expansion coefficient of the conductive plate 3 is set to 3 ppm / K or more and 28 ppm / K or less. The conductive plate 3 has a diameter of 0.2 mm or more and 3 mm or less and a vertical thickness of 0.1 mm or more and 2 mm or less. The conductive plate 3 is connected to the bottom surface of the recess P via a brazing material.

  By making the conductive plate 3 into a disc having a predetermined thickness, it is possible to efficiently absorb the heat in the spherical conductive member 5 or the recess P space and to easily dissipate the heat to the outside. In the recess P space, heat is likely to be trapped when the vibration sensor 1 operates. Therefore, by providing the conductive plate 3, it is possible to easily dissipate the heat in the recess P space to the outside. The conductive plate 3 is set to have a diameter that is more than half the thickness of the substrate 2 and more than half the diameter of the spherical conductive member 5 so as to easily absorb heat from the spherical conductive member 5. ing.

In a state where the conductive plate 3 is housed in the recess P, a gap s is formed between the side surface of the conductive plate 3 and the inner wall surface of the recess P.
p1 is provided. The gap sp1 is set so that the side surface of the conductive plate 3 does not contact the inner wall surface of the recess P even if the conductive plate 3 undergoes thermal expansion. If the conductive plate 3 is set in a state in which the conductive plate 3 is fitted in the recess P without a gap, the conductive plate 3 undergoes thermal expansion, and thermal stress is applied from the conductive plate 3 to the inner wall surface of the recess P. 2 may be destroyed. Therefore, by providing the gap sp1 between the side surface of the conductive plate 3 and the inner wall surface of the recess P, the thermal stress from the conductive plate 3 on the inner wall surface of the recess P can be eliminated.

  Further, a through conductor 8 reaching the lower surface of the substrate 2 is provided on the bottom surface of the recess P. The through conductor 8 is electrically connected to the conductive plate 3. The through conductor 8 is provided at the center position of the recess P. The through conductor 8 can transmit heat from the conductive plate 3 and can transmit heat in the concave portion P toward the outside of the through conductor 8. The through conductor 8 is a cylindrical via conductor. The through conductor 8 is, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold or aluminum, or an alloy thereof, or a composite material obtained by mixing a plurality of these materials, or a material thereof. It consists of a composite layer. The through conductor 8 has a diameter set to 0.1 mm or more and 1 mm or less. The through conductor 8 has a vertical length set to 0.2 mm or more and 2 mm or less.

  A metallized layer 9 that is electrically connected to the frame-like conductive member 4 is formed on the upper surface of the substrate 2. The metallized layer 9 is formed except for the periphery of the recess P. The metallized layer 9 is not formed on the inner wall surface of the recess P. The metallized layer 9 is partially provided with an insulating portion, and a metallized portion 10 that is electrically connected to the lid 7 is provided in the insulating portion.

  The metallized layer 9 is electrically insulated from the conductive plate 3 and the metallized portion 10. The metallized layer 9 is made of, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold, or aluminum, an alloy thereof, a composite material in which a plurality of materials are mixed, or a composite layer of these materials.

  The frame-like conductive member 4 is provided on the metallized layer 9 as shown in FIG. The lower surface of the frame-like conductive member 4 is connected to the metallized layer 9 through a brazing material. The frame-shaped conductive member 4 is formed in a cylindrical shape. As shown in FIG. 6, the frame-shaped conductive member 4 is provided so that the center of the conductive plate 3 coincides with the center of the region surrounded by the frame-shaped conductive member 4 in plan view. The frame-like conductive member 4 is made of, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold, or aluminum, an alloy thereof, or a composite material in which a plurality of materials are mixed. The thermal expansion coefficient of the frame-shaped conductive member 4 is set to 3 ppm / K or more and 28 ppm / K or less.

  The frame-shaped conductive member 4 has a size that can be accommodated in the recess P, and has an outer shape of 0.45 mm to 7.5 mm and an inner diameter of 0.3 mm to 6 mm. Further, the frame-like conductive member 4 is set to have a vertical length of 0.4 mm or more and 4 mm or less. A spherical conductive member 5 is accommodated inside the frame-shaped conductive member 4. As shown in FIG. 5, when the spherical conductive member 5 is arranged so that the center of the spherical conductive member 5 coincides with the center of the region surrounded by the frame-shaped conductive member 4, the spherical conductive member 5 is spherical with the inner wall surface of the frame-shaped conductive member 4. An insulating space sp <b> 2 is provided between the surface of the conductive member 5. The insulating space sp <b> 2 changes as the spherical conductive member 5 moves on the conductive plate 3. In the insulating space sp <b> 2, the maximum distance between the inner surface of the frame-shaped conductive member 4 and the surface of the spherical conductive member 5 in the planar direction along the upper surface of the substrate 2 is set to 0.05 mm or more and 2 mm or less. When the vibration sensor 1 tilts inside the electronic device, the spherical conductive member 5 moves inside the frame-shaped conductive member 4 and contacts the inside of the frame-shaped conductive member 4. As a result, the electronic device can detect that the electronic device is tilted.

  The spherical conductive member 5 is provided in contact with the conductive plate 3 in a region on the substrate 2 and surrounded by the frame-shaped conductive member 4. The spherical conductive member 5 can roll on the conductive plate 3 when the vibration sensor 1 is tilted. The spherical conductive member 5 can freely move in the region surrounded by the frame-shaped conductive member 4. The spherical conductive member 5 is made of, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold, or aluminum, an alloy thereof, or a composite material in which a plurality of materials are mixed. The spherical conductive member 5 has a size that fits in a region surrounded by the frame-shaped conductive member 4 and has a diameter of 0.2 mm or more and 5 mm or less.

  The frame body 6 is provided on the substrate 2 and is provided so as to surround the frame-like conductive member 4. The frame body 6 is provided along the edge of the substrate 2. The frame body 6 seals the frame-like conductive member 4 and the spherical conductive member 5. The frame 6 is made of an insulating material, for example, a ceramic material such as alumina, mullite or aluminum nitride, or a glass ceramic material. Or it consists of a composite material which mixed several materials among these materials. The frame 6 has a rectangular outer edge in plan view, and the length of one side of the outer edge is set to 1 mm or more and 10 mm or less. The thickness of the frame 6 in the vertical direction is set to 0.6 mm or more and 6 mm or less. The thermal conductivity of the frame 6 is set to 14 W / m · K or more and 200 W / m · K or less.

  As shown in FIG. 2 or FIG. 5, an in-frame through conductor 11 as a wiring conductor that is electrically connected to the lid body 7 is provided on the upper surface of the frame body 6. The in-frame through conductor 11 passes through the inside of the frame 6 and reaches the lower surface of the substrate 2. The through-frame conductor 11 is made of a conductive material, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold or aluminum, or an alloy thereof, or a composite in which a plurality of these materials are mixed. It consists of a system material or a composite layer of these materials. The thermal expansion coefficient of the frame 6 is set to 4 ppm / K or more and 8 ppm / K or less.

  As shown in FIG. 2 or 6, the substrate 2 is provided with a substrate through conductor 12 that is electrically connected to the metallized layer 9. The substrate through conductor 12 is formed from the upper surface of the substrate 2 to the lower surface of the substrate 2. The substrate through conductor 12 is electrically connected to the frame-like conductive member 4. The through-substrate conductor 12 is made of a conductive material, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold, or aluminum, or an alloy thereof, or a composite system in which a plurality of these materials are mixed. It consists of materials or composite layers of those materials.

  As shown in FIG. 7, the lower surface of the substrate 2 is provided with a pair of lower surface metallization layers 13 at diagonals among the four corners. The pair of lower surface metallization layers 13 are formed in a rectangular shape. And one side 13a of a pair of lower surface metallization layer 13 has projected to the center position of the lower surface. Further, the other 13b of the pair of lower surface metallized layers 13 is provided with a space between the other 13a. On the other hand, 13 a is electrically connected to both the through conductor 8 and the in-frame through conductor 11. The other 13b is electrically connected to the substrate through conductor 12. The lower metallization layer 13 is made of a conductive material, for example, a metal material such as tungsten, molybdenum, nickel, copper, silver, gold, or aluminum, or an alloy thereof, or a mixture of a plurality of these materials. Made of composite material.

  The lid body 7 is provided on the frame body 6 so as to cover the frame-like conductive member 4 and the spherical conductive member 5. The lid body 7 has a function of sealing a space surrounded by the substrate 2 and the frame body 6. The lid body 7 is brazed onto the frame body 6 via a brazing material, for example. Note that the lid 7 is, for example, a metal material such as copper, iron, tungsten, molybdenum, nickel, copper, silver, gold, or aluminum, or an alloy thereof, or a composite system in which a plurality of these materials are mixed. Made of material.

  The lid 7 is electrically connected to the upper surface of the in-frame through conductor 11 as a wiring conductor. The lid 7 passes through the frame 6 and the substrate 2 and is electrically connected to the lower surface metallized layer 13. The lid 7 has the same potential as that of the conductive plate 3 electrically connected through the through conductor 8.

  The vibration sensor 1 according to the present embodiment does not embed the frame-shaped conductive member 4 in the substrate 2 or the frame body 6, and the frame-shaped conductive member 4 varies depending on the difference in thermal expansion coefficient between the frame-shaped conductive member 4 and its surroundings. Even if thermal expansion occurs, the thermal stress applied to the substrate 2 and the frame body 6 can be reduced as compared with the structure in which the spherical conductive member 5 is buried in a part of the substrate 2 and the frame body 6. The possibility that the sensor 1 is destroyed can be reduced.

  In the vibration sensor 1 according to the present embodiment, a frame-shaped conductive member 4 made of a metal material is disposed in a substrate 2 and a frame body 6 made of a ceramic material, and the frame-shaped conductive member 4 in contact with the spherical conductive member 5 is disposed. The structure is not embedded in the substrate 2 or the frame 6. Moreover, since the cylindrical frame-shaped conductive member 4 is formed so as to surround the spherical conductive member 5, the tilted angle can be accurately detected regardless of the orientation of the vibration sensor 1 in the device. And sensing errors can be reduced.

  In addition, this invention is not limited to the above-mentioned form, A various change, improvement, etc. are possible in the range which does not deviate from the summary of this invention. Hereinafter, modifications of the present embodiment will be described.

<Manufacturing method of vibration sensor>
Here, a manufacturing method of the vibration sensor 1 shown in FIG. 1 will be described.

  First, the substrate 2 is prepared. When the substrate 2 is made of, for example, an aluminum oxide sintered body, from a mixture obtained by adding and mixing an organic binder, a plasticizer, a solvent, and the like to raw powders such as aluminum oxide, silicon oxide, magnesium oxide and calcium oxide Mold green sheets.

  Moreover, a high melting point metal powder such as tungsten or molybdenum is prepared, and an organic binder, a plasticizer, a solvent, or the like is added to and mixed with the powder to obtain a metal paste.

  Then, a metal paste is applied to the upper surface of the substrate 2 in the green sheet state by using, for example, a screen printing method to form the metallized layer 9 and the metallized portion 10. Similarly, the lower metallization layer 13 is formed on the lower surface of the substrate 2.

  Further, the substrate 2 in the green sheet state is punched or the like and filled with a metal paste to form the in-frame through conductor 11 and the substrate through conductor 12. A plurality of green sheets can be laminated to obtain an unfired substrate 2. The frame body 6 can be prepared by the same method as the substrate 2.

  Next, the conductive plate 3, the frame-shaped conductive member 4, the spherical conductive member 5 and the lid 7 are prepared. These can be produced in a predetermined shape by using a metal processing method such as metal polishing on an ingot obtained by casting and solidifying a molten metal material into a mold.

Next, firing is performed at a temperature of about 1600 degrees with the prepared unsintered substrate 2 and the frame 6 connected. Then, the substrate 2 and the frame 6 are integrally sintered. Then, the conductive plate 3 is connected to the concave portion P of the substrate 2 by brazing. Further, the frame-like conductive member 4 is connected to the substrate 2 by brazing.
Further, the lid body 7 is brazed onto the frame body 6 in a state where the spherical conductive member 5 is disposed in the region surrounded by the frame-shaped conductive member 4. In this way, the vibration sensor 1 can be manufactured.

DESCRIPTION OF SYMBOLS 1 Vibration sensor 2 Board | substrate 3 Conductive plate 4 Frame-shaped conductive member 5 Spherical conductive member 6 Frame body 7 Cover body 8 Through conductor 9 Metallized layer 10 Metallized part 11 In-frame through conductor 12 Substrate through conductor 13 Lower surface metallized layer P Concave sp1 Gap sp2 Insulation space

Claims (4)

A substrate having a recess on the upper surface;
A conductive plate provided in the recess;
A frame-like conductive member provided on the substrate and surrounding the conductive plate;
A spherical conductive member provided on the substrate and in contact with the conductive plate in a region surrounded by the frame-shaped conductive member;
A frame provided on the substrate and surrounding the frame-shaped conductive member;
A lid provided on the frame and covering the spherical conductive member ;
The vibration sensor according to claim 1, wherein the conductive plate is provided so as to be spaced from an inner wall surface of the recess . The vibration sensor according to claim 1 ,
The spherical conductive member is movable in a region surrounded by the frame-shaped conductive member, and a part of the spherical conductive member is in contact with the inner wall surface of the frame-shaped conductive member in a state of being in contact with the conductive plate. Vibration sensor. The vibration sensor according to claim 1 or 2 ,
The frame-shaped conductive member is formed in a cylindrical shape. The vibration sensor according to any one of claims 1 to 3 ,
The vibration sensor is characterized in that the lid is made of a conductive material and is electrically connected to the conductive plate via a wiring conductor provided in the frame and in the substrate.

Images