JP2012242188A - Physical quantity sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a physical quantity sensor that can be used for substantially all objects to be measured and that can measure a strain or load on the object to be measured with high sensitivity regardless of changes in temperature.SOLUTION: A physical quantity sensor includes a first oscillator 23 and a second oscillator 25 having beam-like vibration parts 23a, 25a on a rectangular substrate 22. The first oscillator 23 is arranged in which a longitudinal direction of the first beam-like vibration part 23a forms nearly 45° to a side of the rectangular substrate 22, and the second oscillator 25 is arranged so as to be substantially orthogonal to the first oscillator 23. As a result, a strain or load on an object can be detected.

Description

  The present invention relates to a physical quantity sensor that detects strain and load acting on an object.

  In general, as physical quantity sensors for detecting strain and load acting on an object, those shown in FIGS. 5A and 5B are known (see Patent Document 1). FIG. 5A is a perspective view of a conventional physical quantity sensor. In FIG. 5 (a), reference numeral 1 denotes a vibrator composed of a crystal piece 2, and electrodes 3 that form pairs on both principal surfaces in both ends in the Z direction with the XZ plane of coordinate axes X, Y, and Z as the principal surface. 3 'and electrodes 4 and 4' are formed, and these are used as a first vibrating portion and a second vibrating portion, respectively. The vibrator 1 is processed into a substantially square shape with a constant thickness, that is, the Y direction, and the electrodes 3, 3 ′ and the electrodes 4, 4 ′ are each in the X-axis direction where the main vibration of thickness shear vibration is excited. It is formed long. Therefore, the first vibration part and the second vibration part vibrate at the same vibration frequency. FIG. 5B is a block diagram showing the configuration of a pressure sensor system using this physical quantity sensor. In FIG. 5B, 5 is a measured object, 6 is the first vibrating section, and The connected first oscillation circuit, 7 is a second oscillation circuit connected to the second vibration unit, 8 is a mixer, 9 is an arithmetic circuit, and 10 is a display.

In FIG. 5 (a) (b), an external force to Q ₁ X direction is applied to the first vibrating portion in the vibrator 1 attached to the object to be measured 5, the first vibrating portion and the external force Q ₁ the A compressive force q _{1 in the} direction acts. At the same time, if an external force Q _{2 in the} direction opposite to the external force Q ₁ is applied to the second vibration portion of the vibrator 1, an extension force q _{2 in the} same direction as the external force Q ₂ acts on the second vibration portion. . As a result, distortion due to the compressive force q ₁ occurs in the first vibration part, and the oscillation frequency of the first oscillation circuit 6 including the first vibration part changes from, for example, f ₀ to f ₀ −f ₁ . . Further, the second vibrating part distortion occurs by extension force q _2, the oscillation frequency of the second oscillator circuit 7 including a second vibrating section changes from f ₀ to f ₀ + f _2. When the outputs of these two oscillation circuits are input to the mixer 8, the difference between the oscillation frequencies of the two oscillation circuits from the mixer 8 is Δ = (f ₀ + f ₂ ) − (f ₀ −f ₁ ) = f ₁ + f ₂ Is output. The arithmetic circuit 9 converts the frequency of this signal into a weight value and displays it on the display 10 as a digital value. Thereby, since a larger frequency difference can be obtained than in the case of using a physical quantity sensor having only the first vibration part or the second vibration part, measurement sensitivity can be increased. Furthermore, since fluctuations in the oscillation frequency due to temperature changes can be canceled, strain and load can be accurately measured regardless of temperature changes.

  As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.

JP-A 61-57823

However, in the conventional physical quantity sensor shown in FIGS. 5A and 5B, the first vibration part and the second vibration part are arranged in parallel to each other. There was a problem of being limited. This problem will be described with reference to FIGS. FIG. 6 (a) connects the vibrator 1 of the conventional physical quantity sensor shown in FIG. 5 (a) on the side surface of the beam 11 having one end fixed and a vertical upward external force applied to the other end. Indicates the state. At this time, it is assumed that the vibrator 1 is disposed so as to straddle the neutral surface 12 of the beam. In such a case, since the compressive force acts on the first vibration part in the vibrator 1 and the extension force acts on the second vibration part, the first oscillation circuit including the first vibration part oscillation frequency of 6, for example, changes from f ₀ to f ₀ -f _1. The oscillation frequency of the second oscillator circuit 7 including a second vibrating section changes from f ₀ to f ₀ + f _2. By taking the difference between the outputs of these two oscillation circuits, it is possible to obtain a larger frequency difference than when using a physical quantity sensor having only the first vibration part or the second vibration part. Can be increased. Furthermore, since fluctuations in the oscillation frequency due to temperature changes can be canceled, strain and load can be accurately measured regardless of temperature changes.

FIG. 6B shows a state in which the vibrator 1 of the conventional physical quantity sensor is disposed above the neutral surface 12 on the side surface of the beam 11 shown in FIG. At this time, since the compressive force acts on both the first vibrating portion and the second vibrating portion in the vibrator 1, the oscillation frequency of the first oscillation circuit 6 including the first vibrating portion is, for example, from f _0. to f ₀ -f _1, the oscillation frequency of the second oscillator circuit 7 including a second vibrating section changes from f ₀ to f ₀ -f ₁ '. However, the difference between the outputs of these two oscillation circuits is Δ = (f ₀ −f ₁ ′) − (f ₀ −f ₁ ) = f ₁ −f ₁ ′. The frequency difference is smaller than when a physical quantity sensor having only a vibrating part is used, and the measurement sensitivity is lowered.

FIG. 6C shows the vibrator 1 of the conventional physical quantity sensor shown in FIG. 5A placed on the side surface of the pillar 13 having one end fixed and a vertically downward external force applied to the other end. Indicates the state. At this time, since substantially the same compressive force acts on both the first vibrating portion and the second vibrating portion in the vibrator 1, the oscillation frequency of the first oscillation circuit 6 including the first vibrating portion is, for example, from f ₀ to f ₀ -f _1, changes the oscillation frequency of the second oscillator circuit 7 including a second vibrating section from f ₀ to f ₀ -f _1. Therefore, since the difference between the outputs of these two oscillation circuits is Δ = (f ₀ −f ₁ ) − (f ₀ −f ₁ ) = 0, the external force cannot be measured. As described above, the transducer 1 of the conventional physical quantity sensor has a sensitivity for measuring strain and load, except in a special case where external forces acting in opposite directions act on the first and second vibrating parts arranged in parallel to each other. However, the range in which this physical quantity sensor can be applied is extremely limited.

  The present invention solves the above-mentioned conventional problems, and is applied to virtually all measured objects to measure the strain and load acting on the measured objects with high sensitivity and high accuracy regardless of temperature changes. It is an object of the present invention to provide a physical quantity sensor that can be used.

  In order to achieve the above object, the present invention has the following configuration.

  According to the first aspect of the present invention, a strain generating body that generates strain by an external force, a rectangular substrate, a rectangular substrate formed on the rectangular substrate, and applied to the rectangular substrate. A first vibrator having a first beam-like vibrating portion whose vibration frequency changes according to the amount of strain, and the vibration frequency formed according to the amount of strain applied to the rectangular substrate. A second vibrator having a second beam-like vibrating portion that changes, and the longitudinal direction of the first beam-like vibrating portion of the first vibrator is approximately 45 with respect to the side of the rectangular substrate. The longitudinal direction of the first beam-like vibration part in the first vibrator and the longitudinal direction of the second beam-like vibration part in the second vibrator are substantially orthogonal to each other. And the center of the first beam-like vibrating portion of the first vibrator and the second beam-like shape of the second vibrator. The line connecting the center of the vibration part is parallel to the side of the rectangular substrate, and the midpoint of the line connecting the centers of the two vibrators is substantially coincident with the center of the rectangular substrate. Since the longitudinal direction of the first beam-like vibration part in the first vibrator and the longitudinal direction of the second beam-like vibration part in the second vibrator are substantially orthogonal, the strain generation When an external force along the longitudinal direction of the first beam-like vibrating portion of the first vibrator is applied to the body, or the strain body is sheared in opposite directions along two opposing sides of the rectangular substrate. When a force is applied, the direction of the force acting on the first vibrator and the force acting on the second vibrator can always be reversed, and the vibration frequency of the first vibrator and the second vibrator By detecting the difference between the vibration frequency and the mechanical quantity acting on the strain body, Because, essentially it can be applied to all the object to be measured, which makes it possible to measure the strain or load acting on the object to be measured with high sensitivity regardless of temperature changes, and high precision. Further, since the first vibrator and the second vibrator are arranged in parallel so as to form an angle of about 45 degrees with respect to the side of the rectangular substrate, the physical quantity sensor can be downsized. It is what you have.

  As described above, the physical quantity sensor of the present invention includes a strain generating body that generates strain due to an external force, a rectangular substrate, a strain formed on the rectangular substrate, and a strain applied to the rectangular substrate. A first vibrator having a first beam-shaped vibrating portion whose vibration frequency changes according to the amount, and the vibration frequency changes according to the amount of strain applied to the rectangular substrate formed on the rectangular substrate. And a second vibrator having a second beam-like vibrating portion, the longitudinal direction of the first beam-like vibrating portion of the first vibrator being approximately 45 degrees with respect to the side of the rectangular substrate The longitudinal direction of the first beam-like vibration part in the first vibrator and the longitudinal direction of the second beam-like vibration part in the second vibrator are substantially orthogonal to each other. , The center of the first beam-like vibrating portion of the first vibrator, and the second of the second vibrator A line connecting the center of the oscillating portion is parallel to the side of the rectangular substrate, and a midpoint of the line connecting the centers of the two vibrators is substantially coincident with the center of the rectangular substrate. Since the longitudinal direction of the first beam-like vibrating portion in the first vibrator and the longitudinal direction of the second beam-like vibrating portion in the second vibrator are substantially orthogonal, When an external force along the longitudinal direction of the first beam-like vibrating portion of one vibrator is applied, or shear forces in opposite directions are applied to the strain generating body along two opposing sides of the rectangular substrate. The direction of the force acting on the first vibrator and the force acting on the second vibrator can always be reversed, and the vibration frequency of the first vibrator and the vibration frequency of the second vibrator Since the mechanical quantity acting on the strain generating body is detected by detecting the difference between Therefore, it is possible to measure the strain and load acting on the measured object with high sensitivity and high accuracy regardless of the temperature change, and it is possible to reduce the size. It is what you play.

(A) Top view of physical quantity sensor in embodiment of this invention, (b) AA sectional view taken on the line of the physical quantity sensor in embodiment of this invention. (A) Top view which shows the state which has arrange | positioned the physical quantity sensor in embodiment of this invention in the strain body, (b) BB sectional drawing of the physical quantity sensor in embodiment of this invention (A) Changes in the vibration frequency of the first and second vibrators when an external force is applied to the measurement object in a state where the beam-like vibration parts of the first and second vibrators are in string vibration. The figure shown, (b) The figure which showed the change of the vibration frequency difference of the 1st, 2nd vibrator when external force acted on the to-be-measured body The top view which shows the state which has arrange | positioned the physical quantity sensor in embodiment of this invention in the strain body (A) Perspective view of conventional physical quantity sensor, (b) Block diagram showing the configuration of a pressure sensor system using the physical quantity sensor (A) The figure which shows the state which applied the vibrator | oscillator of the same physical quantity sensor across the neutral surface on the side of the beam where one end is fixed and the vertical upward external force is applied to the other end, (b) The figure which shows the state which has arrange | positioned the vibrator | oscillator of the physical quantity sensor located on the side surface of the beam where one end is fixed and the external force is applied to the other end above the neutral plane. The figure which shows the state which has arrange | positioned the vibrator | oscillator of the same physical quantity sensor on the side surface of the pillar to which one end is fixed and the external force perpendicular | vertical downward is applied to the other end.

  The invention according to claim 1 of the present invention will be described below using embodiments. FIG. 1A is a top view of a physical quantity sensor according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA of FIG. 1A and 1B, 21 is a physical quantity sensor, 22 is a rectangular substrate made of silicon having a (001) surface on its surface, and the surface of the rectangular substrate 22 is made of a silicon oxide layer or a silicon nitride layer. An insulating layer is formed. Reference numeral 23 denotes a first vibrator which is formed by etching the rectangular substrate 22 and has a first beam-like vibrating portion 23a whose vibration frequency changes in accordance with the amount of strain applied to the rectangular substrate 22. . Further, a lower electrode, a piezoelectric layer made of PZT, etc., and a detection element 23b made of an upper electrode are formed in the center of the surface of the first beam-like vibrating portion 23a, and the first beam-like vibrating portion 23a is formed. Similarly, a lower electrode, a piezoelectric layer made of PZT or the like, and a drive element 23c made of an upper electrode are formed in order on both ends of the vibration part 23a, and the detection element 23b and the drive element 23c are connected to a wiring pattern (not shown). Is electrically connected to the land 24.

  Similarly, 25 is formed by etching the rectangular substrate 22 and has a second beam-like vibrating portion 25a whose vibration frequency changes according to the amount of strain applied to the rectangular substrate 22. It is a vibrator. Further, a lower electrode, a piezoelectric layer made of PZT or the like, and a detection element 25b made of an upper electrode are formed in the center of the surface of the second beam-like vibrating portion 25a, and the second beam-like vibrating portion 25a. Similarly, a lower electrode, a piezoelectric layer made of PZT or the like, and a drive element 25c made of an upper electrode are formed in order on both ends of the vibration part 25a, and the detection element 25b and the drive element 25c have wiring patterns (not shown). Is electrically connected to the land 24.

  The longitudinal direction of the beam-like vibrating portion 23 a in the first vibrator 23 is arranged so as to form an angle of about 45 degrees with respect to the side of the rectangular substrate 22, and the beam-like vibrating portion 23 a in the first vibrator 23 is arranged. The longitudinal direction of the vibration part 23a and the longitudinal direction of the second beam-like vibration part 25a in the second vibrator 25 are arranged so as to be substantially orthogonal to each other. Further, a line connecting the center of the beam-like vibrating portion 23a in the first vibrator 23 and the center of the beam-like vibrating portion 25a in the second vibrator 25 is the sides 22a and 22b of the rectangular substrate. The midpoint of the line that is parallel and connects the centers of the two vibrators 23 and 25 is configured to substantially coincide with the center of the rectangular substrate 22. Accordingly, the first vibrator 23 and the second vibrator 25 are arranged side by side at a substantially central portion of the rectangular substrate 22.

  2A is a top view showing a state in which the physical quantity sensor 21 is arranged on the strain body 30, and FIG. 2B is a cross-sectional view taken along the line BB of FIG. 2A. Here, the bottom surface of the physical quantity sensor 21 is formed of a metal-based bonding material such as Au—Au bonding or epoxy so that the strain generated in the strain generating body 30 is transmitted to the first vibrator 23 and the second vibrator 25. The connection is fixed using a material having rigidity such as resin. The longitudinal direction of the beam-like vibrating portion 23 a in the first vibrator 23 is arranged substantially parallel to the length direction of the strain body 30.

  In the above configuration, an AC voltage having a frequency close to the natural frequency fa of the first beam-like vibrating portion 23a is applied from a dynamic signal source (not shown) to the driving element 23c of the first vibrator 23. Then, the first beam-like vibrating portion 23a starts stretching vibration in the longitudinal direction. Due to this stretching vibration, the first beam-like vibrating portion 23a starts string vibration up and down at its own natural frequency fa. The string vibration is received by the detection element 23b, and an AC signal having a frequency equal to the natural frequency fa of the first beam-like vibration part 23a is generated from the detection element 23b. This AC signal is amplified and phase-adjusted and fed back to the driving element 23c. As a result, the first beam-like vibrating portion 23a continues the string vibration at a frequency equal to its natural frequency fa. Similarly, the second beam-like vibrating portion 25a continues the string vibration at a frequency equal to its natural frequency fb.

  Here, the longitudinal direction of the beam-like vibrating portion 23a in the first vibrator 23 is the X-axis direction of silicon, that is, the <100> direction, and the beam-like vibrating portion 25a in the second vibrator 25 is further extended. The longitudinal direction is the Y-axis direction of silicon, that is, the <010> direction. This is because, in silicon, the Young's modulus is minimized in the <100> direction and the <010> direction, so that the length of the string required to generate string vibration at a constant frequency is minimized. This is because the child can be miniaturized.

  FIG. 3A shows an external force applied to the object to be measured in a state where the first and second beam-like vibrating portions 23a and 25a of the first and second vibrators 23 and 25 vibrate vertically. FIG. 6 is a diagram showing changes in the vibration frequency of the first and second vibrators 23 and 25 when is operated.

  Assuming that a tensile force F in the longitudinal direction is applied to the strain generating body 30, the strain generating body 30 expands in the longitudinal direction and contracts in the width direction by a length corresponding to the Poisson's ratio of the strain generating body 30. As a result, an extension force acts on the first beam-like vibrating portion 23a of the first vibrator 23, so that the vibration frequency 31a of the first vibrator 23 increases from fa to fa + fa '. At the same time, since a compressive force acts on the second beam-like vibrating portion 25a of the second vibrator 25, the vibration frequency 31b of the second vibrator 25 decreases from fb to fb−fb ′. become. Contrary to the above, if a compressive force −F in the longitudinal direction is applied to the strain generating body 30, the strain generating body 30 is contracted in the longitudinal direction, and the width direction is the length corresponding to the Poisson's ratio of the strain generating body 30. Will grow. As a result, a compressive force acts on the first beam-like vibrating portion 23a of the first vibrator 23, so that the vibration frequency of the first beam-like vibrating portion 23a decreases from fa to fa-fa '. At the same time, since tension acts on the second beam-like vibrating portion 25a of the second vibrator 25, the vibration frequency of the second beam-like vibrating portion 25 increases from fb to fb + fb ′. .

  In FIG. 3A, when the vibration frequency 31a of the first vibrator 23 and the vibration frequency 31b of the second vibrator 25 intersect, that is, when these two vibration frequencies coincide, And the vibration of the second vibrator 25 interfere with each other, which causes a problem that the measurement accuracy of external force and strain is lowered. Therefore, in the embodiment of the present invention, the vibration frequency 31a of the first vibrator 23 and the vibration frequency 31b of the second vibrator 25 do not intersect within a range in which external force or strain is to be measured. A difference is provided between the vibration frequency fa of the first vibrator 23 and the vibration frequency fb of the second vibrator 25. In the physical quantity sensor according to the embodiment of the present invention, the vibration frequency fa of the first vibrator 23 is set to 120 kHz in a state where no external force acts on the strain generating body 30, and the vibrator frequency fb of the second vibrator 25 is set. And the vibration frequency fa of the first vibrator 23 is set to 30 kHz or more. Accordingly, the vibration of the first vibrator 23 and the vibration of the second vibrator 25 are substantially prevented from interfering with each other within a range in which an external force or strain is to be measured. And the measurement accuracy of distortion can be prevented from decreasing.

  AC signals generated from the first and second beam-like vibrating portions 23a and 25a of the first and second vibrators 23 and 25 are processed in a signal processing device (not shown), and these two AC signals are processed. A signal having a vibration frequency difference Δ is output.

  FIG. 3B is a diagram showing changes in the vibration frequency difference 32 between the first and second vibrators 23 and 25 when an external force is applied to the object to be measured. For example, if a tensile force F in the longitudinal direction is applied to the strain generating body 30, the vibration frequency difference Δ is Δ = (fa + fa ′) − (fb−fb ′) = (fa−fb) + (fa ′ + fb ′) It becomes. By processing the second term of this equation that changes due to an external force in a signal processing device (not shown), it is larger than when using a physical quantity sensor having only the first vibration part or the second vibration part. A frequency difference can be obtained.

  In this way, the strain and load acting on the strain generating body 30 can be measured with high sensitivity by measuring the difference between the output vibration frequencies. On the other hand, in the embodiment of the present invention, the longitudinal directions of the beam-like vibrating portions 23a and 25a in the first and second vibrators 23 and 25 are equivalent directions due to the crystal symmetry of silicon <100>. Since the direction and the <010> direction are set, the temperature characteristics of the Young's modulus are equal to each other, and the direction and rate of change of the vibration frequency with respect to temperature change are the same. As a result, fluctuations in the vibration frequency due to temperature changes can be canceled, so that strain and load can be accurately measured regardless of temperature changes.

  FIG. 4 is a top view showing a state in which the physical quantity sensor 21 is arranged on the strain body 40. Here, the bottom surface of the physical quantity sensor 21 is Au—Au so that the strain generated in the strain generating body 40 is transmitted to the first vibrator 23 and the second vibrator 25 in the same manner as in FIG. The connection is fixed using a metal-based bonding material such as bonding or a rigid material such as epoxy resin. The length directions of the beam-like vibrating portions 23 a and 25 a in the first and second vibrators 23 and 25 are arranged so as to form approximately 45 degrees with the length direction of the strain generating body 40. That is, the sides 22 a and 22 b of the physical quantity sensor 21 are disposed substantially parallel to the length direction of the strain body 40.

  In the above configuration, it is assumed that the first vibrator 23 and the second vibrator 25 continue to vibrate at a frequency equal to their natural frequencies fa and fb, respectively, as in the case of FIG.

  Now, assuming that forces F, that is, shearing forces that face in the longitudinal direction and are opposite to each other, are applied to the upper and lower ends of the strain generating body 40, the first beam-like vibrating portion 23 a in the first vibrator 23 is applied to the upper and lower ends. Since the compression force works, the vibration frequency of the first vibrator 23 decreases from fa to fa-fa ′. At the same time, since an extension force acts on the second beam-like vibrating portion 25a of the second vibrator 25, the vibration frequency of the second vibrator 25 increases from fb to fb + fb ′. The AC signals generated from the first and second beam-like vibrating portions 23a and 25a of the first and second vibrators 23 and 25 are processed in a signal processing device (not shown). A signal having a vibration frequency difference Δ of the AC signal is output. By measuring this difference in vibration frequency, the strain and force in the shear direction acting on the strain generating body 40 can be measured.

  In this manner, by changing the direction in which the physical quantity sensor 21 is arranged on the strain generating body, the strain and load acting on the measured body can be applied to substantially all the measured bodies, regardless of temperature changes. Sensitivity can be measured with high accuracy.

  Further, in the physical quantity sensor of the present invention, the first vibrator 23 and the second vibrator 25 are arranged in parallel so as to form an angle of about 45 degrees with respect to the sides 22a and 22b of the rectangular substrate. Therefore, a physical quantity sensor in which the first vibrator 23 is arranged in parallel to the sides 22a and 22b of the rectangular substrate and the second vibrator 25 is arranged to be orthogonal to the sides 22a and 22b of the rectangular substrate. Compared to this, it has a feature that it can be miniaturized.

  As is apparent from the above description, the physical quantity sensor according to the embodiment of the present invention is configured so that the first vibrator having the beam-shaped vibrating portion on the rectangular substrate forms approximately 45 degrees with respect to the side of the rectangular substrate. Further, a second vibrator having a beam-like vibrating portion on the rectangular substrate is arranged side by side so as to be substantially orthogonal to the first vibrator. When applied to all measured objects, the effect is obtained that the strain and load acting on the measured object can be measured with high sensitivity and high accuracy regardless of temperature changes.

  In the physical quantity sensor according to the embodiment of the present invention, silicon is used as the rectangular substrate. However, the same effect can be obtained even when a constant elastic metal such as Elinba is used.

  In the physical quantity sensor according to the present invention, a first vibrator having a beam-like vibrating portion is arranged on a rectangular substrate so as to form approximately 45 degrees with respect to a side of the rectangular substrate, and the beam is further formed on the rectangular substrate. The second vibrator having a vibrating portion is arranged side by side so as to be substantially orthogonal to the first vibrator. Thus, the second vibrator is small and can be applied to substantially all the measured objects. It has the effect of being able to measure the strain and load acting on the measurement body with high sensitivity and high accuracy regardless of temperature changes, and is particularly useful as a sensor that detects the strain and load acting on the object. It is.

DESCRIPTION OF SYMBOLS 21 Physical quantity sensor 22 Rectangular board | substrate 23 1st vibrator 25 2nd vibrator 23a 1st beam-like vibration part 25a 2nd beam-like vibration part 30, 40 Strain body

Claims (1)

A strain generating body that generates strain due to an external force, a first substrate that is disposed on the strain generating body, is formed on the rectangular substrate, and the vibration frequency changes according to the amount of strain applied to the rectangular substrate. A first vibrator having a beam-like vibrating portion, and a second beam-like vibrating portion that is formed on the rectangular substrate and whose vibration frequency changes according to the amount of strain applied to the rectangular substrate. A second vibrator, and the longitudinal direction of the first beam-like vibrating portion of the first vibrator is arranged so as to form an angle of approximately 45 degrees with respect to a side of the rectangular substrate. The longitudinal direction of the first beam-like vibration part in the first vibrator and the longitudinal direction of the second beam-like vibration part in the second vibrator are substantially orthogonal to each other, and the first vibrator in the first vibrator A line connecting the center of the beam-like vibration part and the center of the second beam-like vibration part in the second vibrator is the rectangular shape. A physical quantity sensor, characterized in that parallel to the substrate side, and the midpoint of the two lines connecting the centers of the vibrator to the center substantially coincides with the rectangular substrate.

Images