JP7089214B2 - Oscillator and vibration device - Google Patents

Description

The present invention relates to an oscillator and a vibrating device.

Generally, a tuning fork type crystal oscillator is known as one of the oscillators. The tuning fork type crystal oscillator includes a tuning fork type crystal vibrating element in which a set of vibrating arms are extended in parallel from the base of the base material. In a tuning fork type crystal vibrating element, a set of vibrating arms vibrates in a direction in which they approach or separate from each other in the horizontal direction.

Cited Document 1 discloses an oscillator including a vibrating arm extending from a base attached to a base. This vibrator further includes a shock-cushioning arm portion extending from the base portion, and by providing a convex portion in a region facing the shock-cushioning arm on the main surface of the base, the shock applied to the vibrating arm is reduced.

Japanese Unexamined Patent Publication No. 2016-149599

Even when the convex portion is provided as in Cited Document 1, since an impact is applied to a part of the vibrating arm of the vibrating element, there is a problem that the frequency characteristic of the vibrating element changes with time due to the influence of the impact.

If the impact applied to the vibrating element can be detected, it is possible to predict the fluctuation of the frequency characteristic due to the influence of the impact and compensate for the fluctuation of the frequency characteristic. Alternatively, the vibrating element can be replaced or discarded as soon as possible with a margin. In the conventional vibration element, it is necessary to provide an impact detection element separately from the vibration element. Therefore, the impact applied to the vibrating element could not be detected directly.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an oscillator and a vibrating device capable of directly detecting an impact applied to a vibrating element and outputting an impact detection from the vibrating element itself.

The vibrator according to one aspect of the present invention has a base member, a support portion supported by the main surface of the base member, and a main body portion extending from the support portion and facing the main surface with a gap. It has a vibrating element that outputs an electric signal including a predetermined resonance frequency obtained by the resonance vibration of the main body portion, and the main body portion of the vibrating element is provided with a first impact detection electrode in a first region. In the second region facing the first region, a second impact detection electrode provided at a predetermined distance from the first detection electrode is included, and the first impact detection electrode and the second impact detection electrode are included. Further, an impact output wiring is provided which is electrically connected to each of the first impact detection electrode and the second impact detection electrode, which are provided so as to take out the change in the electrical characteristics between the two.

According to the present invention, the impact directly applied to the vibrating element can be detected by the output of the vibrating element.

FIG. 1 is an exploded perspective view schematically showing the configuration of the crystal oscillator according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the configuration of a cross section of the crystal oscillator shown in FIG. 1 along the line II-II. FIG. 3 is a plan view schematically showing the configuration of the crystal vibrating element shown in FIG. FIG. 4 is a cross-sectional view schematically showing the configuration of a cross section of the quartz vibration element shown in FIG. 3 along the IV-IV line. FIG. 5 is a cross-sectional view schematically showing the configuration of a cross section of the crystal oscillator shown in FIG. 1 along the VV line. FIG. 6 is a cross-sectional view showing a cushioning arm portion and a protrusion portion when an impact is applied to the crystal vibrating element. FIG. 7 is an exploded perspective view of the crystal oscillator according to the second embodiment of the present invention. FIG. 8 is a cross-sectional view schematically showing the configuration of the cross section of the crystal oscillator shown in FIG. 7 along the line VII-VII. FIG. 9 is a cross-sectional view schematically showing the configuration of the vibration device according to the third embodiment of the present invention. FIG. 10 is a block diagram showing the configuration of the circuit board shown in FIG.

An embodiment of the present invention will be described below. In the description of the drawings below, the same or similar components are represented by the same or similar reference numerals. The drawings are examples, and the dimensions and shapes of each part are schematic, and the technical scope of the present invention should not be limited to the embodiment.

Further, in the following description, a crystal oscillator (Quartz Crystal Resonator Unit) including a crystal vibration element (Quartz Crystal Resonator) will be described as an example of a piezoelectric vibrator (Piezoelectric Resonator Unit). The crystal vibrating element uses a crystal piece (Quartz Crystal Blank) as a piezoelectric body that vibrates according to an applied voltage. However, the piezoelectric vibrator according to each embodiment of the present invention is not limited to the crystal oscillator, and a piezoelectric vibration element provided with another piezoelectric material such as ceramic may be used.

<First Embodiment>
First, the crystal oscillator 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is an exploded perspective view schematically showing the configuration of the crystal oscillator according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the configuration of a cross section of the crystal oscillator shown in FIG. 1 along the line II-II. FIG. 3 is a plan view schematically showing the configuration of the crystal vibrating element shown in FIG.

In FIGS. 1 to 3, the excitation electrodes, connection electrodes, and other electrodes provided in the quartz vibration element 10 are not shown. Further, the first direction D1, the second direction D2, and the third direction D3 shown in the drawing are, for example, directions orthogonal to each other, but are not limited to these as long as they intersect each other. , They may intersect each other at an angle other than 90 °. Further, the first direction D1, the second direction D2, and the third direction D3 are not limited to the direction of the arrow shown in FIG. 1 (positive direction), and include the direction opposite to the arrow (negative direction).

As shown in FIG. 1, the crystal oscillator 1 includes a crystal vibration element 10, a lid member 20, and a base member 30. The lid member 20 and the base member 30 are part of the configuration of a cage for accommodating the crystal vibrating element 10 in the internal space 26. The lid member 20 is joined to the base member 30 via the sealing frame 37 and the joining member 40.

In this way, the lid member 20 and the base member 30 form an internal space 26 for accommodating the crystal vibrating element 10. Thereby, the crystal vibrating element 10 can be protected by the lid member 20 and the base member 30.

The crystal vibrating element 10 includes a crystal piece 11. The crystal piece 11 is, for example, a Z-plate crystal piece. The Z-plate crystal piece is rotated clockwise in the range of 0 to 5 degrees around the Z-axis in a Cartesian coordinate system consisting of, for example, the X-axis, the Y-axis, and the Z-axis, and is rotated by the X-axis and the Y-axis. A surface parallel to the specified surface (hereinafter referred to as "XY surface"; the same applies to a surface specified by another axis or another direction) is the main surface, and the direction parallel to the Z axis is the thickness. The one obtained by cutting and polishing the artificial crystal is used so as to be. The surface of the crystal piece 11 is not limited to the XY surface, and may be a surface inclined several degrees from the XY surface. The X-axis, Y-axis, and Z-axis are crystal axes of artificial quartz, respectively, and the X-axis corresponds to the electric axis, the Y-axis corresponds to the mechanical axis, and the Z-axis corresponds to the optical axis. Further, the X-axis is a polar axis having a positive direction. Hereinafter, the direction parallel to the Y-axis is referred to as a Y-axis direction. The same applies to the other axial directions. As the crystal piece, a different cut other than the Z-plate crystal piece may be applied.

In the first embodiment, the crystal vibrating element 10 is arranged so that the Y axis is parallel to the first direction D1, the X axis is parallel to the second direction D2, and the Z axis is parallel to the third direction D3. Has been done. In the X-axis direction, which is the polar axis, the + X-axis direction is the positive direction of the second direction D2, and the −X-axis direction is the negative direction of the second direction D2. However, the first direction D1 may be along the Y-axis direction, and may be inclined in the range of −5 degrees to +5 degrees from the Y-axis direction, for example. Similarly, the second direction D2 may be along the X-axis direction, and the third direction D3 may also be along the Z-axis direction.

As shown in FIGS. 1 and 3, the crystal vibrating element 10 composed of the crystal piece 11 of the Z plate is a tuning fork type including a base 50, a set of vibrating arm 60, and a cushioning arm 70. It is a crystal vibrating element (Tuning Fork Type Quartz Crystal Resonator).

The base portion 50 connects a set of vibrating arm portions 60 at the end portion of the crystal piece 11 on the negative direction side of the first direction D1. Similarly, the base 50 also connects the buffer arm 70. The base portion 50 has a first main surface (front surface) 50a on the side facing the lid member 20, and a second main surface (back surface) 50b on the side facing the base member 30.

The set of vibrating arm portions 60 is a general term for the first vibrating arm portion 61 and the second vibrating arm portion 62 extending from the positive direction side of the first direction D1 of the base portion 50 and lining up in the second direction D2. Like the base 50, the set of vibrating arm 60s has a first main surface (front surface) 60a on the side facing the lid member 20 and a second main surface (back surface) on the side facing the base member 30. Has 60b. The first main surface 60a and the second main surface 60b of the set of vibrating arm parts 60 are continuous with the first main surface 50a and the second main surface 50b of the base 50, respectively.

The first vibrating arm portion 61 and the second vibrating arm portion 62 are provided so as to sandwich the center line C1, and the first vibrating arm portion 61 is located on the positive direction side of the second direction D2 with respect to the second vibrating arm portion 62. ing. The first vibrating arm portion 61 and the second vibrating arm portion 62 are provided with a bottomed first groove 63a along the first direction D1 on the first main surface 60a, respectively, and the first direction is provided on the second main surface 60b. A bottomed second groove 63b along D1 is provided. The first groove 63a and the second groove 63b face each other in the third direction D3. By providing the first groove 63a and the second groove 63b in this way, the ease of movement of the first vibrating arm portion 61 and the second vibrating arm portion 62 is improved, and the first vibrating arm portion 61 and the second vibrating arm portion 62 are provided. Vibration leakage from the portion 62 to the base 50 can be suppressed. Further, each of the first vibrating arm portion 61 and the second vibrating arm portion 62 includes a weight portion 64 at the tip thereof. The number of vibrating arms is not limited to two, and may be three or more.

The cushioning arm portion 70 extends from the base portion 50 in the positive direction in the first direction D1 and is provided between a set of vibrating arm portions 60 in the second direction D2. The length of the cushioning arm 70 in the first direction D1 (hereinafter, simply referred to as “length”) is shorter than the length of the first vibrating arm 61 and the second vibrating arm 62. As shown in FIG. 3, when the buffer arm 70 is viewed in a plan view, the tip of the buffer arm 70 is more negative in the first direction D1 than the tips of the first vibrating arm 61 and the second vibrating arm 62. It is located on the directional side. In this way, by making the length of the cushioning arm 70 shorter than the length of the first vibrating arm 61 and the second vibrating arm 62, the length of the first vibrating arm 61 and the second vibrating arm 62 is increased. The size of the first direction D1 of the crystal oscillator 1 can be reduced and the size of the crystal oscillator 1 can be reduced as compared with the configuration in which the length is increased.

The length of the cushioning arm 70 is not particularly limited, and may be longer than the length of the first vibrating arm 61 and the second vibrating arm 62.

Further, although an example in which the crystal vibrating element 10 includes one cushioning arm portion 70 is shown, the present invention is not limited to this. The crystal vibrating element may include a plurality of cushioning arms. Further, the buffer arm portion 70 is provided between a set of vibrating arm portions 60, but the present invention is not limited to this. The cushioning arm may be provided, for example, on the outside of the set of vibrating arms 60 in the second direction D2.

The lid member 20 has a concave shape, specifically a box shape including an opening toward the first main surface 32a of the base member 30, and has an inner surface 24 and an outer surface 25. The lid member 20 is connected to the top surface portion 21 facing the first main surface 32a of the base member 30 and the outer edge of the top surface portion 21, and extends in the normal direction with respect to the main surface of the top surface portion 21. The side wall portion 22 and the like. The shape of the lid member 20 is not particularly limited as long as it can accommodate the crystal vibrating element 10. For example, the lid member 20 has a rectangular shape when the main surface of the top surface portion 21 is viewed in a plane. The lid member 20 has, for example, a long side parallel to the first direction D1, a short side parallel to the second direction D2, and a height parallel to the third direction D3. Further, the lid member 20 has a facing surface 23 facing the first main surface 32a of the base member 30 at the concave opening edge. The facing surface 23 has a frame shape and extends so as to surround the periphery of the crystal vibrating element 10.

The lid member 20 has conductivity. The lid member 20 is, for example, a metal member. Specifically, the lid member 20 is made of an alloy containing iron (Fe) and nickel (Ni) (for example, 42 alloy). A nickel (Ni) layer or the like formed by plating may be provided on the innermost surface (the surface including the inner surface 24) of the lid member 20. Further, a gold (Au) layer or the like may be provided on the outermost surface (the surface including the outer surface 25) of the lid member 20 for the purpose of preventing oxidation or the like. However, the material of the lid member 20 is not particularly limited.

The base member 30 is equipped with a crystal vibrating element 10. Specifically, the crystal vibrating element 10 is oscillatedly held on the first main surface 32a of the base member 30 via the conductive holding members 36a and 36b.

The base member 30 has a flat plate shape. The base member 30 has a long side parallel to the first direction D1 direction, a short side parallel to the second direction D2, and a thickness parallel to the third direction D3.

The base member 30 includes a base 31. The substrate 31 has a first main surface 32a (front surface) and a second main surface 32b (back surface) facing each other. The substrate 31 is a sintered material such as an insulating ceramic (alumina). In this case, the substrate 31 may be sintered by laminating a plurality of insulating ceramic sheets. Alternatively, the substrate 31 may be a glass material (for example, silicate glass or a material containing a main component other than silicate and having a glass transition phenomenon due to temperature rise), a crystal material (for example, AT-cut crystal) or It may be formed of glass epoxy resin or the like. The substrate 31 is preferably made of a heat resistant material. The substrate 31 may be a single layer or a plurality of layers, and when the substrate 31 is a plurality of layers, the substrate 31 includes an insulating layer formed on the outermost layer of the first main surface 32a.

The base member 30 includes electrode pads 33a, 33b, 33c provided on the first main surface 32a, and external electrodes 35a, 35b, 35c, 35d, 35e, 35f provided on the second main surface 32b. The electrode pads 33a, 33b, 33c are electrically connected to the crystal vibrating element 10. Further, the external electrodes 35a, 35b, 35c, 35d, 35e, 35f are electrically connected to a circuit board (not shown). The electrode pad 33a is electrically connected to the external electrode 35a via the via electrode 34a extending in the third direction D3, and the electrode pad 33b is connected to the external electrode via the via electrode 34b extending in the third direction D3. It is electrically connected to 35b, and the electrode pad 33c is electrically connected to the external electrode 35e via a via electrode 34c extending in the third direction D3.

The electrode pads 33a, 33b, 33c are provided on the first main surface 32a near the short side on the negative direction side of the first direction D1 of the base member 30. In the example shown in FIG. 1, the electrode pads 33a, 33b, 33c are arranged apart from the short side of the base member 30 and along the short side direction.

The external electrodes 35a, 35b, 35c, and 35d are provided near the respective corners of the second main surface 32b. In the example shown in FIG. 1, the external electrodes 35a and 35b are arranged directly below the electrode pads 33a and 33b. Thereby, the external electrodes 35a and 35b can be electrically connected to the electrode pads 33a and 33b by the via electrodes 34a and 34b extending in the third direction D3.

The external electrode 35e is arranged directly below the electrode pad 33c. Thereby, the external electrode 35e can be electrically connected to the electrode pad 33c by the via electrode 34c extending in the third direction D3. Further, the external electrode 35e is arranged directly below the protrusion 75, which will be described later, and is electrically connected to the via electrode 34d extending in the third direction D3.

In the example shown in FIG. 1, among the six external electrodes 35a, 35b, 35c, 35d, 35e, 35f, the external electrodes 35a, 35b arranged near the short side on the negative direction side of the first direction D1 of the base member 30. Is an input / output electrode to which the input / output signal of the crystal vibrating element 10 is supplied. Further, the external electrodes 35c and 35d arranged near the short side on the positive direction side of the first direction D1 of the base member 30 are separate from the input signal for instructing the excitation of the crystal vibrating element 10 and the output signal for extracting the resonance frequency. It is an impact detection external electrode that takes out the impact detection output of the system. One of the external electrodes 35c and 35d may be a ground electrode that supplies a ground potential to the lid member 20 to improve the electromagnetic shielding function of the lid member 20. Further, the external electrodes 35c and 35d may be omitted. Further, the remaining two external electrodes 35e and 35f will be described later.

The electrode pads 33a, 33b, 33c of the base member 30 and the external electrodes 35a, 35b, 35c, 35d, 35e, 35f are all made of a metal film. For example, the electrode pads 33a, 33b, 33c and the external electrodes 35a, 35b, 35c, 35d, 35e, 35f have a molybdenum (Mo) layer, a nickel (Ni) layer, and a gold (Au) layer, respectively, from the lower layer to the upper layer. Are laminated and configured. Further, the via electrodes 34a, 34b, 34c, 34d are formed by filling, for example, a via hole (not shown) penetrating the substrate 31 from the first main surface 32a to the second main surface 32b with a metal material such as molybdenum (Mo). Has been done.

The mode of electrical connection between the electrode pad and the external electrode is not limited to the via electrode. For example, the electrical connection between the electrode pad and the external electrode may be achieved by pulling out the extraction electrode on the first main surface 32a or the second main surface 32b. Alternatively, the substrate 31 of the base member 30 is formed of a plurality of layers, the via electrode is extended to the intermediate layer, and the extraction electrode is pulled out in the intermediate layer, whereby the electrode pad or the internal electrode and the external electrode are electrically connected. You may make a connection.

The conductive holding members 36a, 36b, 36c are provided between the first main surface 32a of the base member 30 and the second main surface 50b of the base 50 of the crystal vibrating element 10. The conductive holding members 36a, 36b, 36c electrically connect the crystal vibrating element 10 to the electrode pads 33a, 33b, 33c of the base member 30. The conductive holding members 36a, 36b, 36c are formed of, for example, a conductive adhesive containing a thermosetting resin, an ultraviolet curable resin, or the like, and are a filler for maintaining a distance between the base member and the quartz vibration element, and conductive. It contains additives such as conductive particles for imparting conductivity to the holding member.

A sealing frame 37 is provided on the first main surface 32a of the base member 30. The sealing frame 37 has a rectangular frame shape when viewed in a plan view from the first main surface 32a. The electrode pads 33a and 33b are arranged inside the sealing frame 37, respectively. The sealing frame 37 is provided so as to surround the crystal vibrating element 10. The sealing frame 37 is made of a conductive material. For example, by forming the sealing frame 37 with the same material as the electrode pads 33a and 33b, the sealing frame 37 can be provided at the same time in the step of providing the electrode pads 33a and 33b.

The joining member 40 is provided over the entire circumference of each of the lid member 20 and the base member 30. Specifically, the joining member 40 has a rectangular frame shape when the first main surface 32a of the base member 30 is viewed in a plan view, and is provided on the sealing frame 37. The sealing frame 37 and the joining member 40 are sandwiched between the facing surface 23 of the side wall portion 22 of the lid member 20 and the first main surface 32a of the base member 30.

As shown in FIG. 2, both the lid member 20 and the base member 30 are joined via the sealing frame 37 and the joining member 40, so that the crystal vibrating element 10 is surrounded by the lid member 20 and the base member 30. It is sealed in the internal space 26. In this case, the pressure in the internal space 26 is preferably lower than the atmospheric pressure, and more preferably in a vacuum state.

The shape of the sealing frame 37 in a plan view is not limited to a continuous frame shape, and may be a discontinuous frame shape. Similarly, the shape of the joining member 40 in a plan view is not limited to a continuous frame shape, and may be a discontinuous frame shape.

A protrusion 75 is provided on the first main surface 32a of the base member 30. The protrusion 75 projects from the first main surface 32a of the base member 30 in the positive direction of the third direction D3. The protrusion 75 is provided on the first main surface 32a of the base member 30 in a region facing the crystal vibrating element 10, specifically, a region facing the buffer arm portion 70 of the crystal vibrating element 10. That is, the crystal vibrating element 10 is held by the first main surface 32a of the base member 30 so that the protrusion 75 and the buffer arm 70 overlap when the first main surface 32a of the base member 30 is viewed in a plan view. There is.

The protrusion 75 has a rectangular shape when the first main surface 32a of the base member 30 is viewed in a plan view. The protrusion 75 includes a second impact detection electrode 76 provided on the upper surface (top surface). The second impact detection electrode 76 is electrically connected to the external electrode 35f via the via electrode 34d extending in the third direction D3.

The second impact detection electrode 76 is made of a metal film. For example, the second impact detection electrode 76 is configured by laminating a molybdenum (Mo) layer, a nickel (Ni) layer, and a gold (Au) layer from the lower layer to the upper layer. However, the second impact detection electrode 76 may be a conductor, and the material of the second impact detection electrode 76 is not particularly limited.

Further, the second impact detection electrode 76 is not limited to the case where it is formed on the upper surface of the protrusion 75. The second impact detection electrode 76 may be formed on at least a part of the surface of the protrusion 75, for example, may be formed on the entire surface including the side surface of the protrusion 75, or only a part of the upper surface. It may be formed in.

The protrusion 75 is integrally formed with, for example, the base member 30. Therefore, the protrusion 75 is made of the same material as the base 31 of the base member 30. However, the protrusion 75 is not limited to the configuration integrally formed with the base member 30. The protrusion 75 may be provided as a separate body on the first main surface 32a of the base member 30, for example. In this case, the protrusion 75 is preferably made of a material having a Young's modulus smaller than that of the facing crystal vibrating element 10. For example, the protrusion 75 is made of a resin having a Young's modulus smaller than that of the crystal vibrating element 10 made of the crystal piece 11. Further, the second impact detection electrode 76 may be formed at a position different from the surface of the protrusion 75. When an impact is applied, the protrusion of the resin comes into contact first to absorb the impact, then the main body further bends, and the second impact detection electrode 76 provided at another location is the first impact of the crystal vibration element. The first impact detection electrode 71 and the second impact detection electrode 76 may be arranged at positions close to or in contact with the detection electrode 71. The present invention does not exclude the provision of a plurality of protrusions.

In the present embodiment, the protrusion 75 has an example of having a rectangular shape in a plan view, but the present invention is not limited to this, and the protrusion 75 may have other shapes such as a polygon, a circle, and an ellipse. good. The protrusion 75 may be provided on the side surface of the vibrating arm portion 60 of the tuning fork type crystal vibrating element, or on an extension portion extending from the base portion 50 facing the side surface.

In the crystal vibrating element 10 according to the present embodiment, one end in the long side direction of the crystal piece 11 (the end on the side where the conductive holding members 36a, 36b, 36c are arranged) is a fixed end, and the other end. The end is a free end. However, the position of the fixed end of the crystal vibrating element 10 is not particularly limited.

Next, with reference to FIG. 4, a more detailed configuration of the set of vibrating arms 60 and the operation of the crystal vibrating element 10 will be described. FIG. 4 is a cross-sectional view schematically showing the configuration of a cross section of the quartz vibration element shown in FIG. 3 along the IV-IV line.

As shown in FIG. 4, a first excitation electrode 81 and a second excitation electrode 82 are provided on the surfaces of the first vibrating arm portion 61 and the second vibrating arm portion 62, respectively. The first excitation electrode 81 is provided on both side surfaces of the first vibrating arm portion 61 and the second vibrating arm portion 62. Both side surfaces are a set of side surfaces connecting the first main surface 60a and the second main surface 60b. That is, the first excitation electrode 81 faces each other so as to sandwich the first vibrating arm portion 61 and the second vibrating arm portion 62 in the second direction D2. The second excitation electrode 82 is provided inside each of the first groove 63a and the second groove 63b on the first main surface 60a and the second main surface 60b. Further, the second excitation electrode 82 is also provided on the outside of the first groove 63a and the second groove 63b.

The first excitation electrode 81 and the second excitation electrode 82 are electrodes made of, for example, a multi-layered metal film having nickel (Ni) or chromium (Cr) as a base layer and gold (Au) as the outermost layer. Since chromium has high adhesion to the crystal piece, it is possible to suppress the peeling of the excitation electrode due to continuous operation for a long period of time or the like. Since gold has high chemical stability, it is possible to suppress fluctuations in vibration characteristics due to oxidation of the excitation electrode.

The first excitation electrode 81 and the second excitation electrode 82 are electrically connected to the external electrode 35a and the external electrode 35b through the conductive holding member 36a and the conductive holding member 36b, respectively. When an alternating electric field is applied to the inside of the first vibrating arm 61 and the second vibrating arm 62 via the first exciting electrode 81 and the second exciting electrode 82, the first vibrating arm 61 and the second vibrating arm 62 are applied. Each side surface of 62 expands and contracts based on the magnitude of the voltage of the alternating electric field. By applying an alternating electric field of a specific driving voltage between the first excitation electrode 81 and the second excitation electrode 82, the first vibrating arm portion 61 and the second vibrating arm portion 62 vibrate as a set in FIG. It vibrates at a resonance frequency so as to approach or separate from each other in the direction of the arrow shown at the tip of the arm 60. As a result, an electric signal including a predetermined resonance frequency obtained by the resonance vibration of the vibrating arm portion 60 is output by the conductive holding member 36a and the conductive holding member 36, and the external electrode 35a and the external electrode 35b.

Next, with reference to FIGS. 5 and 6, a more detailed configuration of the cushioning arm 70 and the operation of the cushioning arm 70 and the protrusion 75 will be described. FIG. 5 is a cross-sectional view schematically showing the configuration of a cross section of the crystal vibrating element shown in FIG. 1 along the VV line. FIG. 6 is a cross-sectional view showing a cushioning arm portion and a protrusion portion when an impact is applied to the crystal vibrating element.

As shown in FIG. 5, the cushioning arm portion 70 faces the first main surface 32a of the base member 30 with a gap. Similarly, the vibrating arm portion 60 (not shown) faces the first main surface 32a of the base member 30 with a gap. The vibrating arm portion 60 and the cushioning arm portion 70 correspond to an example of the "main body portion" of the present invention.

The cushioning arm portion 70 has a first main surface (front surface) 70a on the side facing the lid member 20, and a second main surface (back surface) 70b on the side facing the base member 30. The first main surface 70a of the buffer arm 70 is continuous with the first main surface 50a of the base 50, and the second main surface 70b of the buffer arm 70 is continuous with the second main surface 50b of the base 50.

The buffer arm portion 70 includes a first impact detection electrode 71 in a region of a second main surface 70b facing the first main surface 32a of the base member 30 (hereinafter referred to as “first region”). In the example shown in FIG. 5, the first impact detection electrode 71 is provided on the second main surface 70b on the tip end side of the buffer arm portion 70.

The cushioning arm 70 further includes a connecting electrode 72 on the second main surface 70b. The connection electrode 72 extends in the first direction D1 on the second main surface 70b. One end of the connection electrode 72 (right end in FIG. 5) is electrically connected to the first impact detection electrode 71, and the other end of the connection electrode 72 (left end in FIG. 5) is electrically connected to the conductive holding member 36c. Has been done. As a result, the first impact detection electrode 71 is electrically connected to the external electrode 35e via the connection electrode 72, the conductive holding member 36c, the electrode pad 33c, and the via electrode 34c.

The connection electrode 72 electrically connected to the first impact detection electrode 71, the conductive holding member 36c, the electrode pad 33c, the via electrode 34c, the external electrode 35e, and the second impact detection electrode 76 are electrically connected. The above-mentioned via electrode 34d and the external electrode 35f to be connected correspond to an example constituting the "impact output wiring" of the present invention.

The first impact detection electrode 71 and the connection electrode 72 are made of a metal film. For example, the first impact detection electrode 71 and the connection electrode 72 are configured by laminating a molybdenum (Mo) layer, a nickel (Ni) layer, and a gold (Au) layer from the lower layer to the upper layer, respectively. However, the first impact detection electrode 71 and the connection electrode 72 may be any conductor, and the materials of the first impact detection electrode 71 and the connection electrode 72 are not particularly limited.

The protrusion 75 is provided in a region facing the first impact detection electrode 71 (hereinafter, referred to as “second region”) provided on the second main surface 70b of the buffer arm portion 70. A gap with a predetermined distance d1 is provided between the protrusion 75 and the first impact detection electrode 71. This distance d1 is set to be equal to or less than the smallest distance between the first main surface 32a of the base member 30, the second main surface 60b of the vibrating arm 60, and the second main surface 70b of the cushioning arm 70. There is.

The cross-sectional shape of the protrusion 75 is rectangular in the example shown in FIG. However, the cross-sectional shape of the protrusion 75 is not limited to this, and may be another shape such as a polygon, a semicircle, or a semi-elliptical shape.

Here, when an impact containing the component of the third direction D3 is applied to the crystal transducer 1 from the outside, as shown in FIG. 6, the vibrating arm portion 60 and the cushioning arm portion 70 are displaced by the action of the impact force, and the second 1 The predetermined distance d1 between the impact detection electrode 71 and the second impact detection electrode 76 changes. Specifically, the cushioning arm 70 of the crystal vibrating element 10 is deformed in the negative direction of the third direction D3, and the second main surface 70b of the cushioning arm 70 comes into contact with the first main surface 32a of the base member 30. Alternatively, it may approach the first main surface 32a of the base member 30.

In the crystal oscillator 1, the vibrating arm portion 60 and the cushioning arm portion 70 of the crystal vibrating element 10 include a first impact detection electrode 71 provided in the first region, and the second region facing the first region is formed. It includes a second impact detection electrode 76 provided with a predetermined distance d1 from the first impact detection electrode 71, and changes in electrical characteristics between the first impact detection electrode 71 and the second impact detection electrode 76. Connection electrodes 72, conductive holding members 36c, electrode pads 33c, via electrodes 34c, 34d, which are electrically connected to each of the first impact detection electrode 71 and the second impact detection electrode 76, which are provided so as to be taken out. Further, external electrodes 35e and 35f are further provided. As described above, when an impact containing a component of the third direction D3 is applied to the crystal vibrating element 10 from the outside, the vibrating arm portion 60 and the cushioning arm provided with the first impact detection electrode 71 are provided by the action of the impact force. The portion 70 is displaced, and a predetermined distance d1 between the first impact detection electrode 71 and the second impact detection electrode 76 changes. As a result, the connection electrode 72, the conductive holding member 36c, the electrode pad 33c, the via electrodes 34c, 34d, and the external electrodes 35e, 35f are generated by the change of the predetermined distance d1, the first impact detection electrode 71. The change in electrical characteristics between and the second impact detection electrode 76 can be extracted. Therefore, the impact applied to the crystal vibrating element 10 can be detected by the output of the crystal vibrating element 10.

Further, the crystal oscillator 1 has the first impact detection electrode 71 and the second impact detection at a position where the predetermined distance d1 becomes smaller according to the displacement of the vibrating arm portion 60 and the cushioning arm portion 70 generated by the action of the impact force. The electrode 76 and the electrode 76 are arranged. Thereby, for example, the conduction due to the contact between the first impact detection electrode 71 and the second impact detection electrode 76, or the change in the capacitance due to the proximity of the first impact detection electrode 71 and the second impact detection electrode 76 is detected. can do.

Further, the crystal oscillator 1 is arranged at a position where the first impact detection electrode 71 comes into contact with the second impact detection electrode 76 first due to the displacement of the vibrating arm portion 60 and the cushioning arm portion 70 generated by the action of the impact force. Has been done. As a result, the first impact detection electrode 71 comes into contact with the second impact detection electrode 76 before the portion other than the first impact detection electrode 71 comes into contact with the second impact detection electrode 76, so that the first impact detection electrode The conduction due to the contact between the 71 and the second impact detection electrode 76 can be detected first.

Further, in the crystal oscillator 1, the predetermined distance d1 is equal to or less than the minimum distance between the second main surface 60b of the vibrating arm portion 60 and the second main surface 70b of the cushioning arm portion 70. As a result, it is possible to detect a minute impact applied to the crystal vibrating element 10.

Further, in the crystal oscillator 1, the first region is provided in the vibrating arm portion 60 and the cushioning arm portion 70 of the crystal vibrating element 10 facing the first main surface 32a of the base member 30. Thereby, by providing the second region on the first main surface 32a of the base member 30, the first impact detection electrode 71 and the second impact detection electrode 76 facing each other can be easily realized.

Further, the crystal oscillator 1 further includes a protrusion 75 provided in at least one of the first region and the second region, and is caused by the displacement of the vibrating arm portion 60 and the cushioning arm portion 70 generated by the action of an impact force. The protrusion 75 provided on one side is arranged at a position where it first contacts the other of the first region and the second region. As a result, the protrusion 75 contacts the other of the first region and the second region to absorb the impact force before the portion other than the protrusion 75 touches the other of the first region and the second region. , It is possible to reduce the impact force applied to other than the other of the first region and the second region.

Further, in the crystal oscillator 1, a first impact detection electrode 71 or a second impact detection electrode 76 is provided on the surface of the protrusion 75. As a result, the first impact detection electrode 71 comes into contact with the second impact detection electrode 76 before the portion other than the first impact detection electrode 71 comes into contact with the second impact detection electrode 76, so that the first impact detection electrode The conduction due to the contact between the 71 and the second impact detection electrode 76 can be detected first.

Further, in the crystal oscillator 1, the material of the protrusion 75 is composed of a material having a Young's modulus smaller than that of the material of the first region and the material of the second region. As a result, for example, the protrusion 75 provided in the second region is softer than the first region of the opposing crystal vibrating element 10, so that the other of the first region and the second region comes into contact with the protrusion 75 due to the action of the impact force. When the protrusion 75 is deformed, the impact force applied to the other of the first region and the second region can be absorbed.

In the present embodiment, the present invention has been described with reference to an example in which the protrusion 75 is provided on the first main surface 32a of the base member 30, but the present embodiment is not limited thereto. The protrusion may be provided on the second main surface 70b of the cushioning arm 70, for example. In this case, the first impact detection electrode 71 is provided on the surface of the protrusion, and the second impact detection electrode 76 is provided in the region of the first main surface 32a of the base member 30 facing the first impact detection electrode 71. Be done. Alternatively, the protrusion may be provided on both the first main surface 32a of the base member 30 and the second main surface 70b of the cushioning arm 70.

Further, in the present embodiment, the first impact detection electrode 71 is provided on the cushioning arm 70 and the second impact detection electrode 76 is provided on the base member 30, but the present invention is not limited to this. do not have. For example, the first impact detection electrode 71 or the second impact detection electrode 76 may be provided on the weight portion 64 of the vibrating arm portion 60. Specifically, one of the first impact detection electrode 71 and the second impact detection electrode 76 is provided on the second main surface 60b of the weight portion 64, and the base member faces the second main surface 60b of the weight portion 64. The other of the first impact detection electrode 71 and the second impact detection electrode 76 is provided on the first main surface 32a of 30.

Further, in the present embodiment, the lid member 20 has a box shape including an opening, and the base member 30 has a flat plate shape, but the present invention is not limited thereto. For example, the lid member may have a flat plate shape, the base member may have a box shape including an opening facing the main surface of the lid member, and the lid member may have a flat plate shape. Alternatively, both the lid member and the base member may have a box shape including an opening on the side facing each other.

Even if the vibrator according to each embodiment of the present invention has a configuration in which a photolithography step, a dry etching step, and a Si layer growing step are performed on a Si wafer to form a base member, a vibrating element, and a lid member. good. The base member, the support portion of the vibrating element, and the lid member may be integrally formed of the same Si material. At this time, the main body of the vibrating element whose support is supported by the base member is configured to resonate and vibrate by the Coulomb force of the electrostatic electric field, and outputs an electric signal including a specific resonance frequency obtained by the resonance vibration. It may be an oscillator.

<Second Embodiment>
Next, the crystal oscillator according to the second embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG. 7 is an exploded perspective view of the crystal oscillator according to the second embodiment of the present invention. FIG. 8 is a cross-sectional view schematically showing the configuration of the cross section of the crystal oscillator shown in FIG. 7 along the line VII-VII. In addition, the same or similar reference numerals are given to the same or similar configurations as those of the first embodiment. Hereinafter, the points different from the first embodiment will be described.

The crystal oscillator 2 according to the present embodiment includes a crystal vibrating element 10A, and the configuration of the crystal vibrating element 10A is different from that of the first embodiment. Specifically, as shown in FIG. 7, the crystal vibrating element 10A includes an AT-cut type crystal piece 11A. The AT-cut type crystal piece 11A has the Y-axis and the Z-axis of the X-axis, the Y-axis, and the Z-axis, which are the crystal axes of the artificial crystal (Synthetic Quartz Crystal), from the Y-axis around the X-axis. When the axes rotated in the direction of the Z axis by 35 degrees 15 minutes ± 1 minute 30 seconds are the Y'axis and the Z'axis, respectively, the plane parallel to the plane specified by the X and Z'axis (hereinafter, "" It is called "XZ'plane". The same applies to the plane specified by other axes.) It is cut out with the main plane as the main plane. The crystal piece 11A has a first main surface 12a and a second main surface 12b which are XZ'planes facing each other.

The crystal piece 11A, which is an AT-cut crystal piece, has a long side direction in which a long side parallel to the X-axis direction extends, a short side direction in which a short side parallel to the Z'axis direction extends, and a Y'axis direction. It has a thickness direction in which the thickness parallel to is extended. Further, the crystal piece 11A has a rectangular shape on the XZ'plane.

Quartz vibration elements using AT-cut quartz pieces have high frequency stability over a wide temperature range. Further, since the crystal structure of quartz crystal is stable, it is possible to manufacture a vibrating element having excellent aging characteristics. The AT-cut crystal vibration element uses a thick slide vibration mode (Thickness Shear Vibration Mode) as the main vibration.

In this embodiment, the crystal piece 11A has a flat plate shape. The first main surface 12a and the second main surface 12b of the crystal piece 11A are flat surfaces, respectively.

The crystal vibration element 10A includes a first excitation electrode 14a and a second excitation electrode 14b constituting a set of electrodes. The first excitation electrode 14a is provided on the first main surface 12a. Further, the second excitation electrode 14b is provided on the second main surface 12b. The first excitation electrode 14a and the second excitation electrode 14b are provided so as to face each other with the crystal piece 11A interposed therebetween in a region including the center of each main surface. The first excitation electrode 14a and the second excitation electrode 14b are arranged so that substantially the entire surface of the XZ'is overlapped with each other.

The first excitation electrode 14a and the second excitation electrode 14b each have a long side parallel to the X-axis direction, a short side parallel to the Z'axis direction, and a thickness parallel to the Y'axis direction. .. In the example shown in FIG. 7, on the XZ'plane, the long sides of the first excitation electrode 14a and the second excitation electrode 14b are parallel to the long sides of the crystal piece 11A, respectively. Similarly, the short sides of the first excitation electrode 14a and the second excitation electrode 14b are parallel to the short sides of the crystal piece 11A, respectively. Further, the long sides of the first excitation electrode 14a and the second excitation electrode 14b are separated from the long sides of the crystal piece 11A, respectively. Similarly, the short sides of the first excitation electrode 14a and the second excitation electrode 14b are separated from the short sides of the crystal piece 11A, respectively.

The crystal vibrating element 10A includes extraction electrodes 15a and 15b and connection electrodes 16a and 16b. The connection electrode 16a is electrically connected to the first excitation electrode 14a via the extraction electrode 15a. Further, the connection electrode 16b is electrically connected to the second excitation electrode 14b via the extraction electrode 15b. The connection electrode 16a and the connection electrode 16b are terminals for electrically connecting to the base member 30, respectively. The connection electrode 16a and the connection electrode 16b are provided on the second main surface 12b of the crystal piece 11A, respectively. The connection electrode 16a and the connection electrode 16b are arranged along the short side of the crystal piece 11A in the vicinity of the short side on the negative side of the X-axis.

The extraction electrode 15a electrically connects the first excitation electrode 14a and the connection electrode 16a. Specifically, the extraction electrode 15a extends from the first excitation electrode 14a toward the negative X-axis direction and the positive Z'axis on the first main surface 12a, and from the first main surface 12a to the crystal piece 11A. It extends through each side surface to reach the second main surface 12b and is electrically connected to the connection electrode 16a on the second main surface 12b. Further, the extraction electrode 15b electrically connects the second excitation electrode 14b and the connection electrode 16b. Specifically, the extraction electrode 15b extends from the second excitation electrode 14b in the negative direction of the X-axis on the second main surface 12b and is electrically connected to the connection electrode 16b on the second main surface 12b. ing. By extending the extraction electrodes 15a and 15b in this way, they are electrically connected to the first excitation electrode 14a and the second excitation electrode 14b provided on both main surfaces of the first main surface 12a and the second main surface 12b. The connected connection electrodes 16a and 16b can be arranged on one of the second main surfaces 12b.

The connection electrodes 16a and 16b are electrically connected to the electrodes of the base member 30 via the conductive holding members 36a and 36b.

The crystal vibration element 10A includes a first impact detection electrode 71 and a connection electrode 72. The first impact detection electrode 71 and the connection electrode 72 are provided on the second main surface 12b of the crystal piece 11A, respectively. The first impact detection electrode 71 is arranged in the vicinity of the short side of the crystal piece 11A on the positive direction side of the X axis along the short side direction. The connection electrode 72 extends from the first impact detection electrode 71 toward the Z'axis positive direction and the X-axis negative direction so as to avoid the second excitation electrode 14b, and further avoids the connection electrode 16a and the connection electrode 16b. It extends in the negative direction of the Z'axis and the negative direction of the X-axis. The connection electrode 72 is electrically connected to the electrode of the base member 30 via the conductive holding member 36c.

The materials of the first excitation electrode 14a and the second excitation electrode 14b, the extraction electrodes 15a and 15b, the connection electrodes 16a and 16b, the first impact detection electrode 71, and the connection electrode 72 are not particularly limited. However, for example, a chromium (Cr) layer may be provided as a base, and a gold (Au) layer may be further provided on the surface of the chromium layer.

In the present embodiment, the configuration of the crystal vibrating element 10A including the flat plate-shaped crystal piece 11A has been described, but the present invention is not limited thereto. The crystal piece may adopt a mesa-shaped structure in which the vibrating portion including the center of the main surface is thicker than the peripheral portion, or may adopt an inverted mesa structure in which the vibrating portion is thinner than the peripheral portion. Alternatively, the crystal piece may have a convex shape or a bevel shape in which the change in thickness (step) between the vibrating portion and the peripheral portion continuously changes. Further, as the cut angle of the crystal piece, a different cut other than the AT cut, for example, a BT cut or the like may be applied.

In the crystal vibrating element 10A according to the present embodiment, one end in the long side direction of the crystal piece 11A (the end on the side where the conductive holding members 36a and 36b are arranged) is a fixed end, and the other end is a fixed end. It is a free end. Further, the crystal vibrating element 10A has a rectangular shape on the XZ'plane.

The position of the fixed end of the crystal vibrating element 10A is not particularly limited. As a modification, the crystal vibrating element 10A may be fixed to the base member 30 at both ends of the crystal piece 11A in the long side direction. In this case, the electrodes of the crystal vibrating element 10 and the base member 30 may be formed by fixing the crystal vibrating element 10A at both ends of the crystal piece 11A in the long side direction.

In the crystal oscillator 2 according to the present embodiment, an alternating electric field is applied between a set of the first excitation electrode 14a and the second excitation electrode 14b in the quartz vibration element 10A via the external electrodes 35a and 35b of the base member 30. Apply. As a result, the vibrating portion of the crystal piece 11A vibrates in a predetermined vibration mode such as the thickness slip vibration mode, and the resonance characteristic associated with the vibration is obtained.

Further, the first impact detection electrode 71 provided on the second main surface 12b of the crystal vibrating element 10A and the first main surface 32a of the base member 30 are provided via the external electrodes 35e and 35f of the base member 30. The conduction between the second impact detection electrode 76 of the protrusion 75 or the change in capacitance between the first impact detection electrode 71 and the second impact detection electrode 76 is detected. As a result, the impact applied to the crystal vibrating element 10A whose main vibration is the thickness slip vibration mode can be detected by the output of the crystal vibrating element 10A.

<Third Embodiment>
Next, the vibration device according to the third embodiment of the present invention will be described with reference to FIG. 9. FIG. 9 is a cross-sectional view schematically showing the configuration of the vibration device according to the third embodiment of the present invention. FIG. 9 is a view in the same cross-sectional view as that of FIG. FIG. 10 is a block diagram showing the configuration of the circuit board shown in FIG. The same reference numerals are given to the same configurations as those of the first embodiment. Hereinafter, the points different from the first embodiment will be described.

The vibration device 100 according to the present embodiment includes the crystal oscillator 1 of the first embodiment described above and the circuit board 90. As shown in FIG. 9, the crystal oscillator 1 is provided on the circuit board 90. Specifically, the second main surface 32b of the base member 30 is installed on the upper surface of the circuit board 90. The external electrodes 35a, 35b, 35c, 35d, 35e, and 35f provided on the second main surface 32b of the base member 30 are electrically connected to the circuit board 90, respectively.

The vibration device 100 may be configured to include the crystal oscillator 2 of the second embodiment instead of the crystal oscillator 1 of the first embodiment.

As shown in FIG. 10, the circuit board 90 includes a vibration control circuit 91, a detection circuit 92, a comparison circuit 93, a counter circuit 94, a storage circuit 95, and an output control circuit 96.

The vibration control circuit 91 is electrically connected to each of the external electrode 35a and the external electrode 35b. The vibration control circuit 91 is configured to control the vibration of the crystal vibration element 10. Specifically, the vibration control circuit 91 applies an alternating electric field between the first excitation electrode 81 and the second excitation electrode 82 of the crystal vibration element 10 via the external electrode 35a and the external electrode 35b, and the crystal vibration element The first vibrating arm portion 61 and the second vibrating arm portion 62 of 10 are vibrated. Then, the vibration control circuit 91 controls the resonance vibration of the first vibrating arm portion 61 and the second vibrating arm portion 62 by controlling the magnitude of the voltage of the alternating electric field.

The detection circuit 92 is electrically connected to each of the external electrode 35e and the external electrode 35f. The detection circuit 92 is configured to detect the number of times an impact is applied to the crystal oscillator 1. In one example, the detection circuit 92 has a voltage of a predetermined value between the first impact detection electrode 71 of the crystal vibration element 10 and the second impact detection electrode 76 of the base member 30 via the external electrode 35e and the external electrode 35f. Is applied. When the impact applied to the crystal vibrating element 10 is less than a predetermined magnitude, a gap d1 is provided between the first impact detection electrode 71 and the second impact detection electrode 76, so that the first impact The detection electrode 71 and the second impact detection electrode 76 do not come into contact with each other. On the other hand, when the impact applied to the crystal vibrating element 10 is a predetermined magnitude or more, the first impact detection electrode 71 and the second impact detection electrode 76 come into contact with each other, and the first impact detection electrode 71 and the second impact detection electrode 76 Conducts. The value of the current flowing at this time or the amount of electricity (charge) over a predetermined time changes depending on the contact area, contact time, etc. between the first impact detection electrode 71 and the second impact detection electrode 76, and these are the magnitudes of the impact. It is proportional to or substantially proportional to the electric charge. Therefore, the detection circuit 92 detects the current value flowing due to the contact between the first impact detection electrode 71 and the second impact detection electrode 76, for example, to conduct the first impact detection electrode 71 and the second impact detection electrode 76. The number of times can be detected.

In this way, the detection circuit 92 detects the number of times of conduction between the first impact detection electrode 71 and the second impact detection electrode 76 via the external electrodes 35e and 35f, and thus joins the crystal vibration element 10 by the number of times of conduction. The number of impacts can be quantitatively detected.

In another example, the detection circuit 92 detects the number of changes in capacitance between the first impact detection electrode 71 and the second impact detection electrode 76. Specifically, the detection circuit 92 has a predetermined value between the first impact detection electrode 71 of the crystal vibration element 10 and the second impact detection electrode 76 of the base member 30 via the external electrode 35e and the external electrode 35f. Apply the voltage of. At this time, since a gap with a distance d1 is provided between the first impact detection electrode 71 and the second impact detection electrode 76 and is insulated, the first impact detection electrode 71 and the second impact detection electrode 76 have a gap. Stores an electric charge (electrostatic energy) proportional to the capacitance. Here, if the distance between the first impact detection electrode 71 and the second impact detection electrode 76 becomes closer or farther, the capacitance between the first impact detection electrode 71 and the second impact detection electrode 76 Will change to increase or decrease, respectively. Therefore, the detection circuit 92 first detects, for example, the amount of electric charge that moves when the distance d1 between the first impact detection electrode 71 and the second impact detection electrode 76 changes, that is, the current value. At least one of the number of times the change in capacitance between the impact detection electrode 71 and the second impact detection electrode 76 exceeds the upper limit threshold and the number of times the change in capacitance falls below the lower limit threshold can be detected.

In this way, the detection circuit 92 determines at least one of the number of times the change in capacitance between the first impact detection electrode 71 and the second impact detection electrode 76 exceeds the upper limit threshold value and the number of times the change in capacitance falls below the lower limit threshold value. By detecting, the number of impacts in both directions, that is, the distance between the first impact detection electrode 71 and the second impact detection electrode 76, the impact acting to approach and the impact acting to move away, is detected. Can be done.

In any of the configurations, the detection circuit 92 includes a current-voltage conversion circuit, converts the voltage value into a voltage value corresponding to the detected current value, and outputs the voltage value.

The voltage value output by the detection circuit 92 is input to the comparison circuit 93. The comparison circuit 93 compares this voltage value with a predetermined threshold value, and outputs a voltage of a value (level) based on the comparison result. The comparison circuit 93 includes, for example, a comparator. A voltage value output by the detection circuit 92 is input to the first input terminal of the comparator, and a constant voltage having a predetermined threshold value is input to the second input terminal. When the voltage value of the first input terminal is larger than the predetermined threshold value of the second input terminal, the comparison circuit 93 outputs a high level (hereinafter referred to as “H level”) output signal. On the other hand, when the voltage value of the first input terminal is equal to or less than a predetermined threshold value of the second input terminal, the comparison circuit 93 outputs a low level (hereinafter referred to as “L level”) output signal. In this way, the comparison circuit 93 converts the voltage value of the analog signal output from the detection circuit 92 into a digital signal.

The voltage signal output by the comparison circuit 93 is input to the counter circuit 94. For example, the counter circuit 94 counts when an H level output signal is input, and does not count when an L level output signal is input. As a result, the number of impacts applied to the crystal vibrating element 10 is integrated. The counter circuit 94 outputs this integrated number.

In the storage circuit 95, the voltage signal output by the comparison circuit 93, that is, the number of times of conduction or the number of changes in capacitance, and the integrated number of the counter circuit 94, that is, the integrated number or capacitance of the number of conductions. The total number of changes is input. The storage circuit 95 stores the number of times of conduction or the number of changes in capacitance and the integrated number of times of conduction or the number of times of change in capacitance. As a result, the integrated number of the number of times of conduction or the integrated number of the number of changes of the capacitance is stored, so that the history of the impact acting on the crystal vibrating element 10 can be stored.

The output control circuit 96 is accessiblely connected to the storage circuit 95. The output control circuit 96 reads out the integrated number stored in the storage circuit 95, and outputs a signal according to the impact history state to the outside based on the integrated number. As a result, a signal corresponding to the impact history state is output to the outside, so that the deterioration state of the crystal vibrating element 10 due to the impact can be transmitted to the external device. Therefore, it is possible to predict the life variation of the crystal vibrating element 10 due to the application of impact with higher accuracy, and it is possible to appropriately replace or dispose of the crystal vibrating element 10 according to the usage environment.

In the present embodiment, the example in which the crystal oscillator 1 is provided on the circuit board 90 has been described, but the present invention is not limited thereto. For example, when the lid member of the crystal oscillator has a flat plate shape and the base member of the crystal oscillator has a box shape including an opening, the circuit board 90 is fixed to the inner bottom surface of the base member and the lid member. And may be configured to be accommodated in the internal space of the base member.

The exemplary embodiments of the present invention have been described above. In the crystal oscillator 1, the base member 30, the base portion 50 supported by the first main surface 32a of the base member 30, and the vibration extending from the base portion 50 and facing the first main surface 32a with a gap. A crystal vibrating element 10 having an arm portion 60 and a cushioning arm portion 70 and outputting an electric signal including a predetermined resonance frequency obtained by the resonance vibration of the vibrating arm portion 60 and the buffering arm portion 70 is provided, and crystal vibration is provided. The vibrating arm portion 60 and the cushioning arm portion 70 of the element 10 include a first impact detection electrode 71 provided in the first region, and a first impact detection electrode 71 is designated as a second region facing the first region. A second impact detection electrode 76 provided with a distance d1 of the above, provided to extract changes in electrical properties between the first impact detection electrode 71 and the second impact detection electrode 76. 1 Connection electrode 72 electrically connected to each of the impact detection electrode 71 and the second impact detection electrode 76, a conductive holding member 36c, an electrode pad 33c, via electrodes 34c, 34d, and external electrodes 35e, 35f. , Further prepare. Here, when an impact containing a component of the third direction D3 is applied to the crystal vibrating element 10 from the outside, the vibrating arm portion 60 and the cushioning arm portion 70 provided with the first impact detection electrode 71 due to the action of the impact force. Displaces, and a predetermined distance d1 between the first impact detection electrode 71 and the second impact detection electrode 76 changes. As a result, the connection electrode 72, the conductive holding member 36c, the electrode pad 33c, the via electrodes 34c, 34d, and the external electrodes 35e, 35f are the first impact detection electrode 71 generated by changing a predetermined distance. The change in electrical characteristics between the second impact detection electrode 76 and the second impact detection electrode 76 can be extracted. Therefore, the impact applied to the crystal vibrating element 10 can be detected by the output of the crystal vibrating element 10.

Further, in the above-mentioned crystal oscillator 1, the first impact detection electrode 71 and the second impact detection electrode 71 and the second impact detection electrode 71 are located at positions where the predetermined distance d1 becomes smaller according to the displacement of the vibrating arm portion 60 and the cushioning arm portion 70 generated by the action of the impact force. The impact detection electrode 76 is arranged. Thereby, for example, the conduction due to the contact between the first impact detection electrode 71 and the second impact detection electrode 76, or the change in the capacitance due to the proximity of the first impact detection electrode 71 and the second impact detection electrode 76 is detected. can do.

Further, in the above-mentioned crystal oscillator 1, the position where the first impact detection electrode 71 comes into contact with the second impact detection electrode 76 first due to the displacement of the vibrating arm portion 60 and the buffer arm portion 70 generated by the action of the impact force. Is located in. As a result, the first impact detection electrode 71 comes into contact with the second impact detection electrode 76 before the portion other than the first impact detection electrode 71 comes into contact with the second impact detection electrode 76, so that the first impact detection electrode The conduction due to the contact between the 71 and the second impact detection electrode 76 can be detected first.

Further, in the above-mentioned crystal oscillator 1, the predetermined distance d1 is equal to or less than the smallest distance between the second main surface 60b of the vibrating arm portion 60 and the second main surface 70b of the cushioning arm portion 70. As a result, it is possible to detect a minute impact applied to the crystal vibrating element 10.

Further, in the above-mentioned crystal oscillator 1, the first region is provided on the vibrating arm portion 60 and the cushioning arm portion 70 of the crystal vibrating element 10 facing the first main surface 32a of the base member 30. Thereby, by providing the second region on the first main surface 32a of the base member 30, the first impact detection electrode 71 and the second impact detection electrode 76 facing each other can be easily realized.

Further, in the above-mentioned crystal oscillator 1, the protrusion 75 provided in at least one of the first region and the second region is further provided, and the displacement of the vibrating arm portion 60 and the cushioning arm portion 70 generated by the action of the impact force. The protrusion 75 provided on one side is arranged at a position where it comes into contact with the other of the first region and the second region first. As a result, the protrusion 75 contacts the other of the first region and the second region to absorb the impact force before the portion other than the protrusion 75 touches the other of the first region and the second region. , It is possible to reduce the impact force applied to other than the other of the first region and the second region.

Further, in the above-mentioned crystal oscillator 1, the first impact detection electrode 71 or the second impact detection electrode 76 is provided on the surface of the protrusion 75. As a result, the first impact detection electrode 71 comes into contact with the second impact detection electrode 76 before the portion other than the first impact detection electrode 71 comes into contact with the second impact detection electrode 76, so that the first impact detection electrode The conduction due to the contact between the 71 and the second impact detection electrode 76 can be detected first.

Further, in the above-mentioned crystal oscillator 1, the material of the protrusion 75 is composed of a material having a Young's modulus smaller than that of the material of the first region and the material of the second region. As a result, for example, the protrusion 75 provided in the second region is softer than the first region of the opposing crystal vibrating element 10, so that the other of the first region and the second region comes into contact with the protrusion 75 due to the action of the impact force. When the protrusion 75 is deformed, the impact force applied to the other of the first region and the second region can be absorbed.

Further, in the above-mentioned crystal oscillator 1, the base member 30 and the lid member 20 forming the internal space 26 for accommodating the crystal vibrating element 10 are further provided. Thereby, the crystal vibrating element 10 can be protected by the lid member 20 and the base member 30.

Further, in the above-mentioned crystal oscillator 1, the crystal vibrating element 10 is a tuning fork type crystal vibrating element including a base portion 50 and a set of vibrating arm portions 60 extending from the base portion 50 in the first direction D1. Thereby, the impact applied to the tuning fork type crystal vibrating element can be detected by the output of the tuning fork type crystal vibrating element.

Further, in the crystal oscillator 1 described above, the tuning fork type piezoelectric vibration element extends from the base 50 in the first direction D1 and further includes a buffer arm portion 70 including a first impact detection electrode 71 or a second impact detection electrode 76. .. Thereby, the impact applied to the tuning fork type crystal vibrating element can be detected by using the buffer arm portion 70 including the first impact detection electrode 71 or the second impact detection electrode 76. Therefore, it is possible to suppress fluctuations in the frequency characteristics of the tuning fork type crystal vibrating element as compared with the case where an impact is detected using a set of vibrating arm portions 60.

Further, in the above-mentioned crystal oscillator 1, a protrusion 75 is formed on the buffer arm 70. As a result, the protrusion 75 contacts the other of the first region and the second region to absorb the impact force before the portion other than the protrusion 75 touches the other of the first region and the second region. For example, the impact force applied to the base 50 or the vibrating arm 60 can be reduced.

Further, in the above-mentioned crystal oscillator 1, the tip of the vibrating arm portion 60 includes a weight portion 64 provided with a first impact detection electrode 71 or a second impact detection electrode 76. Thereby, the impact applied to the tuning fork type crystal vibrating element can be detected by using the weight portion 64 provided with the first impact detection electrode 71 or the second impact detection electrode 76.

Further, in the crystal oscillator 2, the crystal vibration element 10A is a crystal vibration element whose main vibration is the thickness slip vibration mode. As a result, the impact applied to the crystal vibrating element 10A whose main vibration is the thickness slip vibration mode can be detected by the output of the crystal vibrating element 10A.

Further, in the vibrating device 100, via any of the above-mentioned crystal oscillators 1 and 2, a connection electrode 72, a conductive holding member 36c, an electrode pad 33c, via electrodes 34c and 34d, and external electrodes 35e and 35f. A detection circuit 92 for detecting the number of times of conduction between the first impact detection electrode 71 and the second impact detection electrode 76 is provided. Thereby, the number of times of impact applied to the crystal vibrating element 10 can be quantitatively detected by the number of times of conduction.

Further, in the above-mentioned crystal oscillator 1, the first impact detection electrode 71 is attached to the second impact detection electrode 76 by the vibration arm portion 60 and the cushioning arm portion 70 due to the displacement of the vibrating arm portion 60 and the cushioning arm portion 70 generated by the action of the impact force. It is arranged at the position where it comes into contact with the arm 70 first. As a result, in the vibrating arm portion 60 and the cushioning arm portion 70, the first impact detection electrode 71 has a second impact before the portion other than the first impact detection electrode 71 comes into contact with the second impact detection electrode 76. Since it comes into contact with the detection electrode 76, the number of times of conduction due to contact between the first impact detection electrode 71 and the second impact detection electrode 76 can be detected first.

Further, in the vibrating device 100, via any of the above-mentioned crystal oscillators 1 and 2, a connection electrode 72, a conductive holding member 36c, an electrode pad 33c, via electrodes 34c and 34d, and external electrodes 35e and 35f. A detection circuit 92 that detects at least one of the number of times the change in capacitance between the first impact detection electrode 71 and the second impact detection electrode 76 exceeds the upper limit threshold and the number of times the change in capacitance falls below the lower limit threshold. Be prepared. Here, if the distance between the first impact detection electrode 71 and the second impact detection electrode 76 becomes closer or farther, the capacitance between the first impact detection electrode 71 and the second impact detection electrode 76 Will change to increase or decrease, respectively. Therefore, by detecting at least one of the number of times the change in capacitance between the first impact detection electrode 71 and the second impact detection electrode 76 exceeds the upper limit threshold value and the number of times the change in capacitance falls below the lower limit threshold value, the first 1 The number of impacts in both directions of the impact acting to approach and the impact acting to move away can be detected by the distance between the electrodes 71 and the second impact detecting electrode 76.

Further, the vibration device 100 described above further includes a storage circuit 95 that stores the integrated number of conductions, and an output control circuit 96 that outputs a signal according to the impact history state to the outside based on the integrated number. .. As a result, the cumulative number of times of conduction is stored, so that the history of the impact acting on the crystal vibrating element 10 can be stored. Further, since the signal corresponding to the impact history state is output to the outside, the deterioration state of the crystal vibrating element 10 due to the impact can be transmitted to the external device. Therefore, it is possible to predict the life variation of the crystal vibrating element 10 due to the application of impact with higher accuracy, and it is possible to appropriately replace or dispose of the crystal vibrating element 10 according to the usage environment.

Further, in the above-mentioned vibration device 100, a storage circuit 95 that stores the integrated number of changes in capacitance, and an output control circuit 96 that outputs a signal according to the impact history state to the outside based on the integrated number. , Further prepare. As a result, the cumulative number of changes in the capacitance is stored, so that the history of the impact acting on the crystal vibrating element 10 can be stored. Further, since the signal corresponding to the impact history state is output to the outside, the deterioration state of the crystal vibrating element 10 due to the impact can be transmitted to the external device. Therefore, it is possible to predict the life variation of the crystal vibrating element 10 due to the application of impact with higher accuracy, and it is possible to appropriately replace or dispose of the crystal vibrating element 10 according to the usage environment.

It should be noted that each of the embodiments described above is for facilitating the understanding of the present invention, and is not for limiting the interpretation of the present invention. The present invention can be modified / improved without departing from the spirit thereof, and the present invention also includes an equivalent thereof. That is, those skilled in the art with appropriate design changes to each embodiment are also included in the scope of the present invention as long as they have the features of the present invention. For example, each element included in each embodiment and its arrangement, material, condition, shape, size, and the like are not limited to those exemplified, and can be appropriately changed. Further, each embodiment is an example, and it goes without saying that partial substitutions or combinations of the configurations shown in different embodiments are possible, and these are also included in the scope of the present invention as long as the features of the present invention are included. ..

1,2 ... Crystal oscillator, 10,10A ... Crystal vibrating element, 11,11A ... Crystal piece, 12a ... First main surface, 12b ... Second main surface, 14a ... First excitation electrode, 14b ... Second excitation electrode , 15a ... drawer electrode, 15b ... drawer electrode, 16a ... connection electrode, 16b ... connection electrode, 20 ... lid member, 21 ... top surface, 22 ... side wall, 23 ... facing surface, 24 ... inner surface, 25 ... outer surface, 26. ... Internal space, 30 ... Base member, 31 ... Base, 32a ... First main surface, 32b ... Second main surface, 33a ... Electrode pad, 33b ... Electrode pad, 33c ... Electrode pad, 34a, 34b, 34c, 34d ... Via electrodes, 35a, 35b, 35c, 35d, 35e, 35f ... External electrodes, 36a, 36b, 36c ... Conductive holding member, 37 ... Sealing frame, 40 ... Joining member, 50 ... Base, 50a ... First main surface , 50b ... second main surface, 60 ... vibrating arm, 60a ... first main surface, 60b ... second main surface, 61 ... first vibrating arm, 62 ... second vibrating arm, 63a ... first groove, 63b ... 2nd groove, 64 ... Weight part, 70 ... Buffer arm part, 70a ... 1st main surface, 70b ... 2nd main surface, 71 ... 1st impact detection electrode, 72 ... Connection electrode, 75 ... Projection part, 76 ... 2nd impact detection electrode, 81 ... 1st excitation electrode, 82 ... 2nd excitation electrode, 90 ... circuit board, 91 ... vibration control circuit, 92 ... detection circuit, 93 ... comparison circuit, 94 ... counter circuit, 95 ... storage Circuit, 96 ... Output control circuit, 100 ... Vibration device, d1, d1'... Distance, D1 ... 1st direction, D2 ... 2nd direction, D3 ... 3rd direction

Claims (19)

With the base member
It has a support portion supported on the main surface of the base member and a main body portion extending from the support portion and facing the main surface with a gap, and is obtained by resonance vibration of the main body portion. It is equipped with a vibrating element that outputs an electric signal including a predetermined resonance frequency.
The main body of the vibrating element includes a first impact detection electrode provided in the first region.
The second region facing the first region and provided on the base member includes a second impact detection electrode provided at a predetermined distance from the first impact detection electrode.
It is electrically connected to each of the first impact detection electrode and the second impact detection electrode provided so as to extract the change in electrical characteristics between the first impact detection electrode and the second impact detection electrode. Impact output wiring and
Further comprising a protrusion provided in either the first region or the second region .
The first impact detection electrode or the second impact detection electrode is provided on the protrusion .
Oscillator. The first impact detection electrode and the second impact detection electrode are arranged at positions where the predetermined distance becomes smaller according to the displacement of the main body generated by the action of the impact force in the thickness direction.
The oscillator according to claim 1. The first impact detection electrode and the second impact detection electrode are located at positions where the first impact detection electrode comes into contact with the second impact detection electrode first due to the displacement of the main body generated by the action of the impact force. And are placed,
The oscillator according to claim 2. The predetermined distance is equal to or less than the smallest distance of the gap.
The oscillator according to any one of claims 1 to 3. The first region is provided in the main body portion of the vibrating element facing the main surface of the base member.
The oscillator according to any one of claims 1 to 4. The first impact detection electrode and the said One of the second impact detection electrodes and the protrusion are arranged.
The oscillator according to any one of claims 1, 2, 4, and 5. The first impact detection electrode or the second impact detection electrode is provided on the surface of the protrusion.
The oscillator according to claim 6. The material of the protrusion is composed of a material having a Young's modulus smaller than that of either the material of the first region and the material of the second region.
The oscillator according to claim 6 or 7. Along with the base member, a lid member forming an internal space for accommodating the vibrating element is further provided.
The oscillator according to any one of claims 1 to 8. The vibrating element is a tuning fork type piezoelectric vibrating element including a base portion and a vibrating arm portion extending in a first direction from the base portion.
The oscillator according to any one of claims 6 to 8. The tuning fork type piezoelectric vibration element extends from the base portion in the first direction and further includes a buffer arm portion including the first impact detection electrode or the second impact detection electrode.
The oscillator according to claim 10. The protrusion is formed on the cushioning arm.
The oscillator according to claim 11. The tip of the vibrating arm includes a weight portion provided with the first impact detection electrode or the second impact detection electrode.
The oscillator according to claim 10. The vibrating element is a piezoelectric vibrating element whose main vibration is the thickness slip vibration mode.
The oscillator according to any one of claims 1 to 9. The oscillator according to any one of claims 1 to 14, and the oscillator.
A detection circuit for detecting the number of times of conduction between the first impact detection electrode and the second impact detection electrode via the impact output wiring is provided.
Vibration device. The first impact detection is performed at a position where the first impact detection electrode comes into contact with the second impact detection electrode first in the main body due to the displacement of the main body generated by the action of the impact force in the thickness direction. The electrode and the second impact detection electrode are arranged,
The vibrating device according to claim 15. The oscillator according to any one of claims 1 to 14, and the oscillator.
Detects at least one of the number of times the change in capacitance between the first impact detection electrode and the second impact detection electrode exceeds the upper threshold value and the number of times it falls below the lower limit threshold value via the impact output wiring. With a detection circuit to
Vibration device. A storage circuit that stores the cumulative number of times of continuity, and
An output control circuit that outputs a signal according to the impact history state to the outside based on the integrated number, and
Further prepare,
The vibrating device according to any one of claims 15 or 16. A storage circuit that stores the integrated number of changes in capacitance,
An output control circuit that outputs a signal according to the impact history state to the outside based on the integrated number, and
Further prepare,
The vibrating device according to claim 17.

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