Sensor module

Abstract

This sensor module comprises: a first member; a second member having a Young's modulus lower than that of the first member; and a sensor that is for detecting deformation of the second member and that is in contact with the second member. The distance between the first member and the sensor is longer than the distance between the first member and the second member.

Description

Sensor Module

[0001] The present invention relates to a sensor module including a sensor that detects deformation of a member.

[0002] Patent Document 1 describes a displacement sensor including an elastic body and a piezoelectric element. The piezoelectric element is attached to a first main surface of the elastic body. The elastic body bends when an external force is applied to the elastic body. For example, when the elastic body bends, the piezoelectric element expands. The piezoelectric element generates a voltage according to the amount of expansion of the piezoelectric element.

[0003] International Publication No. 2012 / 137897

[0004] In the field of the displacement sensor described in Patent Document 1, there is a demand for a sensor module that reduces the amount of noise contained in the signal output by the sensor that detects the deformation of a member.

[0005] An object of the present invention is to provide a sensor module in which noise is less likely to be included in the signal output by a sensor that detects deformation of a member.

[0006] A sensor module according to one embodiment of the present invention comprises: a first member; a second member having a Young's modulus lower than that of the first member; and a sensor that detects deformation of the second member and is in contact with the second member, wherein the distance between the first member and the sensor is longer than the distance between the first member and the second member.

[0007] In the following, X and Y are parts or members of the sensor module. In this specification, unless otherwise specified, each part of X is defined as follows: The front part of X means the front half of X. The rear part of X means the rear half of X. The left part of X means the left half of X. The right part of X means the right half of X. The upper part of X means the upper half of X. The lower part of X means the lower half of X. The front end of X means the front end of X. The rear end of X means the rear end of X. The left end of X means the left end of X. The right end of X means the right end of X. The upper end of X means the upper end of X. The lower end of X means the lower end of X.

[0008] Furthermore, "X is located above Y" means that X is located directly above Y. Therefore, when viewed in the vertical direction, X overlaps with Y. "X is located above Y" means that X is located directly above Y and that X is located diagonally above Y. Therefore, when viewed in the vertical direction, X may or may not overlap with Y. This definition also applies to directions other than the upward direction.

[0009] According to the sensor module of the present invention, noise is less likely to be included in the signal output by the sensor that detects deformation of a member.

[0010] FIG. 1 is a perspective view showing the appearance of the sensor module 1. FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. FIG. 3 is a view showing the first member 10 elastically deforming in the up-down direction. FIG. 4 is a view showing the sensor 13 viewed from below. FIG. 5 is a cross-sectional view taken along line B-B in FIG. 4. FIG. 6 is a view showing the signal Sig output from the sensor 13 when the first member 10 elastically deforms in the up-down direction. FIG. 7 is a view showing the first member 10 elastically deforms in the left-right direction. FIG. 8 is a view showing the signal Sig output from the sensor 13 when the first member 10 elastically deforms in the left-right direction. FIG. 9 is a view showing the signal Sig output from the sensor 13 when the upper portion UP and the right portion RP of the first member 10 elastically deform in the lower-left direction. FIG. 10 is a view showing a sensor module 1a according to Modification 1. FIG. 11 is a view showing a sensor module 1b1 according to Modification 2. FIG. 12 is a view showing a sensor module 1b2 according to Modification 2. FIG. 13 is a view showing a sensor module 1c according to Modification 3. FIG. 14 is a view showing a sensor module 1d according to Modification 4. Fig. 15 is a diagram showing a sensor module 1e according to Modification 5. Fig. 16 is a diagram showing a sensor module 1f according to Modification 6. Fig. 17 is a diagram showing a sensor module 1g1 according to Modification 7. Fig. 18 is a diagram showing a sensor module 1g2 according to Modification 7.

[0011] [First embodiment] A sensor module 1 according to a first embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a perspective view showing the appearance of the sensor module 1. Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1. Fig. 3 is a diagram showing the first member 10 elastically deformed in the vertical direction. Fig. 4 is a view of the sensor 13 viewed from below. Fig. 5 is a cross-sectional view taken along line B-B in Fig. 4.

[0012] In this embodiment, directions are defined as follows. As shown in FIG. 1 , the direction in which the sensor module 1 extends is defined as the front-rear direction. As shown in FIG. 2 , the direction in which the sensor 13 and the second member 12 are lined up is defined as the up-down direction. The direction in which the sensor 13 and the second member 12 are lined up in this order is defined as the down direction. The direction in which the second member 12 and the sensor 13 are lined up in this order is defined as the up direction. The direction perpendicular to the front-rear direction and the up-down direction is defined as the left-right direction. However, the front-rear direction, the up-down direction, and the left-right direction are defined for the purpose of explanation. Therefore, the front-rear direction, the up-down direction, and the left-right direction when the sensor module 1 is actually used do not necessarily match the front-rear direction, the up-down direction, and the left-right direction in this embodiment.

[0013] In this embodiment, the sensor module 1 is used in an electronic device such as an electronic cigarette, etc. As shown in FIG.

[0014] In this embodiment, as shown in Figures 1 and 2, the first member 10 has a cylindrical shape including an inner peripheral surface IS and an outer peripheral surface OS. The first member 10 has a cylindrical shape with a central axis CAX extending in the front-to-rear direction. The first member 10 is symmetrical about the central axis CAX. In this embodiment, the first member 10 has a cylindrical shape. The material of the first member 10 is, for example, a metal having a Young's modulus of 40 GPa or more. Such a first member 10 is, for example, a magnesium alloy.

[0015] As shown in FIG. 3 , the first member 10 elastically deforms. For example, the first member 10 elastically deforms in the vertical direction when the user 200 pushes the first member 10 in the vertical direction. Specifically, as shown in FIGS. 2 and 3 , the first member 10 has a lower portion DP located below the central axis CAX and an upper portion UP located above the central axis CAX. The upper portion UP is elastically deformable in the downward direction, and the lower portion DP is elastically deformable in the upward direction. For example, as shown in FIG. 2 , the user 200 pinches the lower portion DP and the upper portion UP with their fingers. This applies an upward force to the lower portion DP. As a result, the lower portion DP elastically deforms in the upward direction. Therefore, when the first member 10 elastically deforms, the lower portion DP elastically deforms in the upward direction. Furthermore, a downward force is applied to the upper portion UP. As a result, the upper portion UP elastically deforms in the downward direction. Therefore, when the first member 10 is elastically deformed, the upper portion UP is elastically deformed downward.

[0016] As shown in FIG. 2 , the support member 11 is plate-shaped and has upper and lower surfaces aligned vertically. The support member 11 is located within the first member 10. Therefore, the user 200 cannot touch the support member 11. The support member 11 is in contact with the inner circumferential surface IS. The right and left ends of the support member 11 are in contact with the inner circumferential surface IS. The right and left ends of the support member 11 are fixed to the inner circumferential surface IS. The support member 11 supports the second member 12 and the sensor 13. The Young's modulus of the support member 11 is, for example, higher than the Young's modulus of the second member 12. Such a support member 11 is, for example, a circuit board on which electronic components are mounted.

[0017] As shown in FIG. 2 , the second member 12 has a rectangular parallelepiped shape with upper and lower surfaces aligned vertically. Therefore, the second member 12 has a rectangular shape when viewed in the front-to-rear direction. The second member 12 is located within the first member 10. The second member 12 is located on top of the support member 11. The lower surface of the second member 12 is in contact with the upper surface of the support member 11. The right end of the second member 12 is located to the right of the central axis CAX. The left end of the second member 12 is located to the left of the central axis CAX. The upper surface of the second member 12 is located above the central axis CAX. When the first member 10 is not elastically deformed, the second member 12 is not in contact with the first member 10. Specifically, the upper right corner PE1 and the upper left corner PE2 of the second member 12 are located closest to the first member 10. A gap exists between the corner PE1 and the inner circumferential surface IS, and a gap exists between the corner PE2 and the inner circumferential surface IS. Therefore, when the first member 10 is not elastically deformed, the second member 12 is separated from the first member 10. The second member 12 is softer than the first member 10. Specifically, the Young's modulus of the second member 12 is lower than the Young's modulus of the first member 10. Such a second member 12 is formed from a resin such as silicone rubber.

[0018] When the first member 10 elastically deforms, the second member 12 comes into contact with the first member 10. Specifically, when the first member 10 elastically deforms, the second member 12 comes into contact with the inner circumferential surface IS. In this embodiment, when the first member 10 elastically deforms, the corners PE1 and PE2 come into contact with the inner circumferential surface IS. Specifically, as shown in FIGS. 3 and 4 , the upper portion UP includes a first contact portion CP1 located to the right of the central axis CAX and a second contact portion CP2 located to the left of the central axis CAX. When the first member 10 elastically deforms, the first contact portion CP1 and the second contact portion CP2 come into contact with the second member 12. Specifically, when the first member 10 elastically deforms, the first contact portion CP1 comes into contact with the corner portion PE1. When the first member 10 elastically deforms, the second contact portion CP2 comes into contact with the corner portion PE2. A gap exists between the corner PE1 and the inner peripheral surface IS, and between the corner PE2 and the inner peripheral surface IS. Therefore, when the deformation amount of the first member 10 is small, the second member 12 does not come into contact with the first member 10.

[0019] As shown in FIG. 4 , the sensor 13 has a rectangular shape with long sides extending in the front-rear direction and short sides extending in the left-right direction. As shown in FIGS. 2 and 3 , the sensor 13 is located within the first member 10. The sensor 13 is located on the second member 12. The sensor 13 is in contact with the second member 12. The sensor 13 is not in contact with the first member 10. Specifically, the sensor 13 is not in contact with the first member 10 both when the first member 10 is not elastically deformed and when the first member 10 is elastically deformed. The shortest distance between the first member 10 and the sensor 13 is longer than the shortest distance between the first member 10 and the second member 12. In this embodiment, the distance between the first member 10 and the sensor 13 is longer than the distance between the first contact portion CP1 and the corner PE1. Furthermore, the shortest distance between the first member 10 and the sensor 13 is longer than the shortest distance between the second contact portion CP2 and the corner PE2. Therefore, as shown in Figure 3, when the first member 10 elastically deforms so that its width in the vertical direction decreases, the first member 10 comes into contact with the second member 12 before coming into contact with the sensor 13.

[0020] As shown in FIG. 5, the sensor 13 includes a first electrode 130, a piezoelectric film 131, a second electrode 132, a charge amplifier (not shown), and an AD converter (not shown).

[0021] The piezoelectric film 131 has a sheet shape with long sides extending in the front-rear direction and short sides extending in the left-right direction. The piezoelectric film 131 has a first main surface SF1 and a second main surface SF2 aligned in the up-down direction.

[0022] The piezoelectric film 131 generates an electric charge according to the amount of deformation of the piezoelectric film 131. The piezoelectric film 131 has a characteristic that the polarity of the electric charge generated when the piezoelectric film 131 is stretched in the left-right direction is opposite to the polarity of the electric charge generated when the piezoelectric film 131 is stretched in the front-back direction. Specifically, the piezoelectric film 131 is a film formed from a chiral polymer. An example of a chiral polymer is polylactic acid (PLA), particularly poly-L-lactic acid (PLLA). PLLA has a helical main chain structure. PLLA has piezoelectric properties in which the molecules are oriented when uniaxially stretched. The piezoelectric film 131 has a piezoelectric constant of d14. As shown in FIG. 4 , the uniaxial stretching direction OD of the piezoelectric film 131 forms an angle of 45 degrees with respect to both the left-right direction and the front-back direction. This 45 degrees includes, for example, an angle of approximately 45 degrees ±10 degrees. As a result, the piezoelectric film 131 generates an electric charge when the piezoelectric film 131 is stretched in the left-right direction or the front-back direction. For example, when the piezoelectric film 131 is stretched in the left-right direction, a positive electric charge is generated. For example, when the piezoelectric film 131 is stretched in the front-back direction, a negative electric charge is generated. The magnitude of the electric charge depends on the differential value of the deformation amount of the piezoelectric film 131 in the left-right direction or the front-back direction due to the stretching of the piezoelectric film 131.

[0023] Furthermore, the piezoelectric film 131 has a characteristic that the polarity of the electric charge generated when the piezoelectric film 131 is compressed in the left-right direction is opposite to the polarity of the electric charge generated when the piezoelectric film 131 is compressed in the front-back direction. For example, the piezoelectric film 131 generates a negative electric charge when compressed in the left-right direction. For example, the piezoelectric film 131 generates a positive electric charge when compressed in the front-back direction.

[0024] The first electrode 130 is a ground electrode. The first electrode 130 is connected to a ground potential. The first electrode 130 is fixed to the first main surface SF1 with an adhesive (not shown). The first electrode 130 covers the first main surface SF1.

[0025] The second electrode 132 is a signal electrode. The second electrode 132 is fixed to the second main surface SF2 with an adhesive (not shown). The second electrode 132 covers the second main surface SF2.

[0026] The charge amplifier converts the charge generated by the piezoelectric film 131 into a voltage signal, and the AD converter converts the voltage signal into a digital signal.

[0027] The sensor 13 detects deformation of the second member 12. Specifically, the elastic deformation of the first member 10 causes the second member 12 to elastically deform. When the second member 12 elastically deforms, the sensor 13 provided on the upper surface of the second member 12 deforms. The sensor 13 outputs a signal (hereinafter referred to as the signal Sig) corresponding to the deformation of the sensor 13. The signal Sig output from the sensor 13 will be described below with reference to the drawings. FIG. 6 is a diagram showing the signal Sig output from the sensor 13 when the first member 10 elastically deforms in the vertical direction. FIG. 6 shows a case where the user 200 repeatedly elastically deforms the first member 10 in the vertical direction. In FIG. 6, time t1 is the time when the first member 10 begins to elastically deform due to an external force applied to the first member 10. In FIG. 6, time t2 is the time when the first member 10 begins to return to its pre-deformation shape due to a restoring force applied to the first member 10. In FIG. 6, time t3 is the time when the sensor 13 returns to its pre-deformation shape.

[0028] In this embodiment, when the first member 10 is deformed in the up-down direction, the sensor 13 generates a signal Sig having a positive polarity with respect to the reference potential VE. Specifically, the user 200 elastically deforms the upper part UP downward and the lower part DP upward. As a result, the first contact part CP1 comes into contact with the upper right corner PE1 of the second member 12, as shown in FIG. 3 . At this time, a force Pw1 in the lower left direction is applied to the corner PE1 by the first contact part CP1. As a result, the top surface of the second member 12 is pulled in the lower left direction. Furthermore, the second contact part CP2 comes into contact with the upper left corner PE2 of the second member 12. At this time, a force Pw2 in the lower right direction is applied to the corner PE2 by the second contact part CP2. As a result, the top surface of the second member 12 is pulled in the lower right direction. As the top surface of the second member 12 is pulled downward to the left and downward to the right, the top surface of the second member 12 curves and protrudes upward. This causes the sensor 13 provided on the top surface of the second member 12 to expand in the left-right direction. Therefore, the piezoelectric film 131 generates a positive charge. When the expansion of the sensor 13 in the left-right direction stops, the piezoelectric film 131 no longer generates a positive charge. As a result, as shown in FIG. 6 , between time t1 and time t2, the sensor 13 generates a signal Sig having a positive polarity with respect to the reference potential VE.

[0029] The user 200 stops pushing the first member 10 in the up and down direction. In this case, the restoring force generated in the first member 10 causes the first member 10 to return to its pre-deformation shape. As a result, the second member 12 is no longer in contact with the first member 10. At this time, the restoring force generated in the second member 12 causes the second member 12 to return to its pre-deformation shape. In this case, the sensor 13 provided on the upper surface of the second member 12 is deformed so as to return to its pre-deformation shape due to the restoring force generated in the sensor 13. At this time, the piezoelectric film 131 generates a negative charge. When the sensor 13 returns to its pre-deformation shape, the piezoelectric film 131 no longer generates a negative charge. As a result, as shown in FIG. 6 , between time t2 and time t3, the sensor 13 generates a signal Sig having a negative polarity with respect to the reference potential VE.

[0030] (Effect) According to the sensor module 1, noise is less likely to be included in the signal Sig output by the sensor 13. For example, if the user 200 drops the sensor module 1, the sensor module 1 hits the floor or the like. This causes an impact to be applied to the first member 10. The impact applied to the first member 10 causes the first member 10 to elastically deform. Here, in the sensor module 1, the distance between the first member 10 and the sensor 13 is longer than the distance between the first member 10 and the second member 12. Because the distance between the first member 10 and the sensor 13 is longer than the distance between the first member 10 and the second member 12, even if the first member 10 elastically deforms due to an impact such as a drop, the deformation of the first member 10 is less likely to be transmitted to the sensor 13. As a result, noise is less likely to be included in the signal Sig output by the sensor 13 in the sensor module 1 compared to a sensor module in which the sensor is provided on the first member.

[0031] According to the sensor module 1, noise is less likely to be included in the signal Sig output by the sensor 13. For example, when a force is applied to the first member 10 due to an impact such as a fall, the first member 10 elastically deforms. Here, in the sensor module 1, when the first member 10 is not elastically deformed, the second member 12 is separated from the first member 10. Therefore, when the first member 10 elastically deforms due to an impact such as a fall, the first member 10 is less likely to come into contact with the second member 12. Therefore, the second member 12 is less likely to be elastically deformed by a force generated when the sensor module 1 is dropped, etc. This makes it less likely that the sensor 13 provided on the second member 12 will elastically deform. Therefore, the sensor 13 is less likely to elastically deform due to a fall, etc. As a result, noise is less likely to be included in the signal Sig output by the sensor 13.

[0032] In the sensor module 1, the second member 12 and the sensor 13 are located within the first member 10. The Young's modulus of the first member 10 is higher than that of the second member 12. Therefore, when an impact is applied to the sensor module 1, the impact is less likely to be applied to the second member 12 and the sensor 13, which are located within the first member 10. Therefore, the signal Sig output by the sensor 13 is less likely to contain noise.

[0033] According to the sensor module 1, the sensor 13 can more easily detect deformation of the second member 12. Specifically, the Young's modulus of the second member 12 is lower than that of the first member 10. Therefore, when the elastic deformation of the first member 10 causes the second member 12 to elastically deform, the amount of deformation of the second member 12 is likely to be larger than the amount of deformation of the first member 10. The sensor 13 is in contact with the second member 12, which has a larger amount of deformation than the first member 10. Therefore, the output value of the sensor 13 in the sensor module 1 is likely to be larger than the output value of a sensor in a sensor module in which the sensor is provided on the first member.

[0034] In the sensor module 1, when the first member 10 elastically deforms, the first contact portion CP1 located to the right of the central axis CAX and the second contact portion CP2 located to the left of the central axis CAX come into contact with the second member 12. For example, the first contact portion CP1 applies a force Pw1 in a downward and leftward direction to the upper right corner PE1 of the second member 12. This pulls the top surface of the second member 12 in a downward and leftward direction. In addition, the second contact portion CP2 applies a force Pw2 in a downward and rightward direction to the upper left corner PE2 of the second member 12. This pulls the top surface of the second member 12 in a downward and rightward direction. In other words, the first contact portion CP1 and the second contact portion CP2 stretch the top surface of the second member 12 in both the downward and rightward directions. As a result, the amount of deformation of the top surface of the second member 12 tends to be greater than the amount of deformation of the first member 10. The sensor 13 is in contact with the upper surface of the second member 12, which is subject to a larger amount of deformation than the first member 10. In this case, the output value of the sensor 13 in the sensor module 1 tends to be larger than the output value of a sensor in a sensor module in which the sensor is provided on the first member. Therefore, the sensor module 1 makes it easier for the sensor 13 to detect deformation of the second member 12.

[0035] The sensor module 1 includes a support member 11 that supports the second member 12 and the sensor 13. This stabilizes the sensor 13. In other words, the sensor 13 is less likely to vibrate when an impact is applied to the sensor module 1. Therefore, the signal Sig output by the sensor 13 is less likely to contain noise.

[0036] When the first member 10 is not elastically deformed, the second member 12 and the sensor 13 are not in contact with the first member. The support member 11 supports the second member 12 and the sensor 13. In this case, vibrations applied to the first member 10 are transmitted to the sensor 13 via the support member 11. Therefore, compared to a sensor module in which the second member is in direct contact with the first member, the signal Sig output by the sensor 13 is less likely to contain noise.

[0037] In the sensor module 1, the support member 11 is fixed to the inner circumferential surface IS of the first member 10. This stabilizes the support member 11 and the second member 12 fixed to the support member 11. In other words, the support member 11 and the second member 12 are less likely to vibrate.

[0038] Another Operation Example 1 of the Sensor Module 1 Another operation example 1 of the sensor module 1 will be described below with reference to the drawings. FIG. 7 is a diagram illustrating a case where the first member 10 elastically deforms in the left-right direction. FIG. 8 is a diagram illustrating a signal Sig output from the sensor 13 when the first member 10 elastically deforms in the left-right direction. FIG. 8 illustrates a case where the user 200 repeatedly elastically deforms the first member 10 in the left-right direction. In FIG. 8 , time t1 is the time when the first member 10 begins to elastically deform due to an external force applied to the first member 10. In FIG. 8 , time t2 is the time when the first member 10 begins to return to its pre-deformation shape due to a restoring force applied to the first member 10. In FIG. 8 , time t3 is the time when the sensor 13 returns to its pre-deformation shape.

[0039] The sensor module 1 elastically deforms in directions other than the up-down direction. For example, as shown in FIG. 7 , the sensor module 1 elastically deforms in the left-right direction. Specifically, the first member 10 has a right portion RP located to the right of the central axis CAX and a left portion LP located to the left of the central axis CAX. The right portion RP is elastically deformable to the left, and the left portion LP is elastically deformable to the right. For example, the user 200 pinches the right portion RP and the left portion LP with their fingers. This applies a leftward force to the right portion RP. As a result, the right portion RP elastically deforms to the left. Therefore, when the first member 10 elastically deforms, the right portion RP elastically deforms to the left. Furthermore, a rightward force is applied to the left portion LP. As a result, the left portion LP elastically deforms to the right. Therefore, when the first member 10 elastically deforms, the left portion LP elastically deforms to the right.

[0040] When the first member 10 elastically deforms in the left-right direction, the sensor 13 generates a signal Sig having a negative polarity with respect to the reference potential VE. Specifically, the user 200 elastically deforms the left portion LP in the right direction and the right portion RP in the left direction. As a result, the first contact portion CP1 comes into contact with the upper right corner PE1 of the second member 12, as shown in FIG. 7 . At this time, a leftward force Pw3 is applied to the upper portion of the second member 12 by the first contact portion CP1. Furthermore, the second contact portion CP2 comes into contact with the upper left corner PE2 of the second member 12. At this time, a rightward force Pw4 is applied to the upper portion of the second member 12 by the second contact portion CP2. The forces Pw3 and Pw4 compress the upper portion of the second member 12 in the left-right direction. As the upper portion of the second member 12 is compressed in the left-right direction, a force is applied to the lower portion of the second member 12, expanding the lower portion of the second member 12 in the left-right direction. In this case, the upper surface of the second member 12 curves so as to protrude downward. As a result, the sensor 13 provided on the upper surface of the second member 12 is compressed in the left-right direction. Therefore, the piezoelectric film 131 generates a negative charge. When the left-right compression of the sensor 13 stops, the piezoelectric film 131 no longer generates a negative charge. As a result, as shown in FIG. 8 , between time t1 and time t2, the sensor 13 generates a signal Sig having a negative polarity with respect to the reference potential VE.

[0041] The user 200 stops pushing the first member 10 in the left-right direction. In this case, the restoring force generated in the first member 10 causes the first member 10 to return to its pre-deformation shape. As a result, the sensor 13 provided on the upper surface of the second member 12 attempts to return to its pre-deformation shape due to the restoring force generated in the sensor 13. At this time, the piezoelectric film 131 generates a positive charge. When the sensor 13 returns to its pre-deformation shape, the piezoelectric film 131 no longer generates a positive charge. As a result, as shown in FIG. 8 , between time t2 and time t3, the sensor 13 generates a signal Sig having a positive polarity with respect to the reference potential VE.

[0042] Another operation example 2 of the sensor module 1 will now be described with reference to the drawings. Fig. 9 is a diagram showing the signal Sig output from the sensor 13 when the upper part UP and the right part RP of the first member 10 elastically deforms in the lower left direction. In Fig. 9, time t1 is the time when the user 200 starts to press the first member 10.

[0043] The first member 10 may elastically deform in a direction other than the up-down or left-right direction. The magnitude of the signal Sig output from the sensor 13 when the first member 10 elastically deforms in a direction other than the up-down or left-right direction is smaller than the magnitude of the signal Sig output from the sensor 13 when the first member 10 elastically deforms in the up-down or left-right direction. For example, in the sensor module 1, the user 200 elastically deforms the upper portion UP and right portion RP of the first member 10 in a downward and leftward direction. At this time, the corner portion PE1 is elastically deformed leftward and downward by the first contact portion CP1. In this case, a force compressing the rear surface of the second member 12 in a leftward direction and a force expanding the rear surface of the second member 12 in a rightward direction are applied to the rear surface of the second member 12. In addition, no force expanding or compressing the rear surface of the second member 12 is applied to the corner portion PE2. Therefore, the rear surface of the second member 12 is less likely to expand or compress in the left-right direction. As a result, the sensor 13 provided on the rear surface of the second member 12 is less likely to elastically deform. Therefore, for example, as shown in Figure 9, when the upper part UP and right part RP of the first member 10 elastically deform in the downward and left direction, the magnitude of the signal Sig output from the sensor 13 is less than half the magnitude of the signal Sig output from the sensor 13 when the first member 10 elastically deforms in the upward and downward or left and right directions.

[0044] [Modification 1] A sensor module 1a according to Modification 1 will be described below with reference to the drawings. Fig. 10 is a diagram showing a sensor module 1a according to Modification 1.

[0045] The sensor module 1a differs from the sensor module 1 in that the sensor 13 is provided on a surface other than the top surface of the second member 12. In the sensor module 1a, the sensor 13 is located on a side surface of the second member 12. For example, as shown in FIG. 10 , in the sensor module 1a, the sensor 13 is provided on the right surface of the second member 12. Such a sensor module 1a provides the same effects as the sensor module 1.

[0046] [Modification 2] Sensor modules 1b1 and 1b2 according to Modification 2 will now be described with reference to the drawings. Fig. 11 is a diagram showing a sensor module 1b1 according to Modification 2. Fig. 12 is a diagram showing a sensor module 1b2 according to Modification 2.

[0047] Sensor modules 1b1 and 1b2 differ from sensor module 1 in that they each include first members 10b1 and 10b2 that have a different shape from first member 10. First members 10b1 and 10b2 are polygonal when viewed in the front-to-rear direction. For example, as shown in FIG. 11, first member 10b1 is triangular when viewed in the front-to-rear direction. For example, as shown in FIG. 12, first member 10b2 is octagonal when viewed in the front-to-rear direction. Alternatively, the first member may be semicircular when viewed in the front-to-rear direction. Such sensor modules 1b1 and 1b2 achieve the same effects as sensor module 1.

[0048] [Modification 3] A sensor module 1c according to Modification 3 will be described below with reference to the drawings. Fig. 13 is a diagram showing a sensor module 1c according to Modification 3.

[0049] As shown in FIG. 13 , sensor module 1c differs from sensor module 1 in that it includes a first member 10c that includes multiple protrusions TK. The protrusions TK are provided on the upper portion UP. The protrusions TK protrude downward from the inner circumferential surface IS. The protrusions TK are located on the second member 12. When the first member 10c elastically deforms, the protrusions TK come into contact with the second member 12. Such sensor module 1c achieves the same effects as sensor module 1.

[0050] [Modification 4] A sensor module 1d according to Modification 4 will now be described with reference to the drawings. Fig. 14 is a diagram showing a sensor module 1d according to Modification 4.

[0051] Sensor module 1d differs from sensor module 1 in that it includes a first member 10d that has a different shape from first member 10. For example, as shown in Fig. 14, the thickness of an upper portion UP of first member 10d in the vertical direction is greater than the thickness of a lower portion DP of first member 10d in the vertical direction. Such sensor module 1d achieves the same effects as sensor module 1.

[0052] [Modification 5] A sensor module 1e according to Modification 5 will be described below with reference to the drawings. Fig. 15 is a diagram showing a sensor module 1e according to Modification 5.

[0053] 15, sensor module 1e differs from sensor module 1 in that it includes a second member 12e that is different in size from second member 12. Specifically, the length of second member 12e in the left-right direction is shorter than the radius of first member 10. When viewed in the front-rear direction, second member 12e is located to the left of central axis CAX.

[0054] According to the sensor module 1e, for example, the sensor 13 can detect deformation of the second member 12e only when the upper portion UP and the left portion LP of the sensor module 1e elastically deforms rightward or downward.

[0055] [Variation 6] A sensor module 1f according to Variation 6 will now be described with reference to the drawings. Fig. 16 is a diagram showing a sensor module 1f according to Variation 6. In Fig. 16, the second member 12 is seen through. As shown in Fig. 16, the sensor module 1f differs from the sensor module 1 in that the sensor 13 is located inside the second member 12. Such a sensor module 1f achieves the same effects as the sensor module 1.

[0056] [Variation 7] Sensor modules 1g1 and 1g2 according to Variation 7 will now be described with reference to the drawings. Fig. 17 is a diagram showing a sensor module 1g1 according to Variation 7. Fig. 18 is a diagram showing a sensor module 1g2 according to Variation 7. Note that the support member 11 is omitted from Figs. 17 and 18.

[0057] The sensor modules 1g1 and 1g2 differ from the sensor module 1 in that they include first members 10g1 and 10g2 that have different shapes from the first member 10, respectively.

[0058] As shown in Fig. 17, the first member 10g1 is plate-shaped and has upper and lower main surfaces aligned in the vertical direction. In this modification, the second member 12 is in contact with the first member 10g1. The upper surface of the second member 12 is covered by the first member 10g1. The second member 12 is located between the first member 10g1 and the sensor 13.

[0059] As shown in FIG. 18 , the first member 10g2 is plate-shaped with left and right main surfaces aligned in the left-right direction. The vertical length of the first member 10g2 may be longer than or the same as the horizontal length of the first member 10g2. In this modification, the second member 12 is in contact with the first member 10g2. The center and near-center of the second member 12 in the left-right direction are in contact with the lower end of the first member 10g2. The second member 12 is located between the first member 10g2 and the sensor 13. The horizontal length of the second member 12 is longer than the horizontal length of the first member 10g2.

[0060] (Effect) With the sensor module 1g1, noise is less likely to be included in the signal Sig output by the sensor 13. For example, if the user 200 drops the sensor module 1g1, the sensor module 1g1 collides with the floor or the like. This causes an impact to the first member 10g1. The impact applied to the first member 10g1 causes the first member 10g1 to elastically deform. Here, in the sensor module 1g1, the distance between the first member 10g1 and the sensor 13 is longer than the distance between the first member 10g1 and the second member 12. Because the distance between the first member 10g1 and the sensor 13 is longer than the distance between the first member 10g1 and the second member 12, even if the first member 10g1 elastically deforms due to an impact such as a drop, the force generated by the deformation of the first member 10g1 is less likely to be transmitted to the sensor 13. As a result, noise is less likely to be included in the signal Sig output by the sensor 13 in the sensor module 1g1 compared to a sensor module in which the sensor is provided on the first member. For the same reason, the sensor module 1g2 makes it difficult for noise to be included in the signal Sig output by the sensor 13.

[0061] The sensor module 1g1 allows the sensor 13 to more easily detect deformation of the second member 12. Specifically, in the sensor module 1g1, the Young's modulus of the second member 12 is lower than that of the first member 10g1. Therefore, when the elastic deformation of the first member 10g1 causes the elastic deformation of the second member 12, the amount of deformation of the second member 12 is likely to be greater than the amount of deformation of the first member 10g1. The sensor 13 is in contact with the rear surface of the second member 12, which has a greater amount of deformation than the rear surface of the first member 10g1. Therefore, the output value of the sensor 13 in the sensor module 1g1 is likely to be larger than the output value of a sensor in a sensor module in which the sensor is provided on the first member. For the same reason, the sensor module 1g2 allows the sensor 13 to more easily detect deformation of the second member 12.

[0062] In the sensor module 1g1, the sensor 13 is not in contact with the first member 10g1. The sensor 13 is in contact with the second member 12, which is in contact with the first member 10g1. In this case, vibrations applied to the first member 10g1 are transmitted to the sensor 13 via the second member 12. Here, the Young's modulus of the second member 12 is lower than that of the first member 10g1. As a result, the second member 12, which has a lower Young's modulus, has a vibration-damping effect. Therefore, when applied to the first member 10g1, high-frequency vibrations are attenuated by the second member 12. As a result, high-frequency noise is less likely to be included in the signal Sig output by the sensor 13.

[0063] The sensor module according to the present invention is not limited to sensor modules 1, 1a, 1b1, 1b2, 1c, 1d, 1e, 1f, 1g1, and 1g2, and may be modified within the scope of the present invention. In addition, the configurations of sensor modules 1, 1a, 1b1, 1b2, 1c, 1d, 1e, 1f, 1g1, and 1g2 may be combined in any desired manner.

[0064] The second member 12, 12e may have a vibration-damping effect. This prevents the sensor 13 from detecting vibrations having a frequency equal to or higher than a specific frequency. In this case, the second member 12, 12e may be an air spring, a metal coil spring, a vibration-damping rubber, a rubber pad, or the like. For example, an air spring damps vibrations having a frequency equal to or higher than 1 Hz. For example, a metal coil spring damps vibrations having a frequency equal to or higher than 5 Hz. For example, a vibration-damping rubber damps vibrations having a frequency equal to or higher than 20 Hz. For example, a rubber pad damps vibrations having a frequency equal to or higher than 30 Hz.

[0065] In the sensor module 1 a, the sensor 13 may be provided on the left surface, the front surface, or the rear surface of the second member 12.

[0066] The material of the first member 10 does not necessarily have to be a magnesium alloy. Also, the material of the first member 10 does not necessarily have to be a metal.

[0067] In the sensor module 1e, the second member 12e may be located to the right of the central axis CAX when viewed in the front-rear direction.

[0068] The sensor modules 1 g 1 and 1 g 2 may each include a plurality of second members 12 .

[0069] In addition, in sensor modules 1, 1b1, 1b2, 1c, and 1d, if the center of the second member 12 in the left-right direction coincides with the center of the first member 10, 10b1, 10b2, 10c, and 10d in the left-right direction, the sensor 13 can more easily detect the forces applied to corners PE1 and PE2 evenly.

[0070] The present invention has the following structure:

[0071] (1) A sensor module comprising: a first member; a second member having a Young's modulus lower than that of the first member; and a sensor that detects deformation of the second member and is in contact with the second member, wherein the distance between the first member and the sensor is longer than the distance between the first member and the second member.

[0072] (2) The sensor module according to (1), wherein the first member is elastically deformed, and the second member is spaced apart from the first member when the first member is not elastically deformed.

[0073] (3) The sensor module according to (1) or (2), wherein the first member elastically deforms, and when the first member elastically deforms, the second member comes into contact with the first member.

[0074] (4) The sensor module according to any one of (1) to (3), wherein the first member has a cylindrical shape including an inner circumferential surface and an outer circumferential surface, the second member and the sensor are located within the first member, and when the first member is elastically deformed, the second member comes into contact with the inner circumferential surface.

[0075] (5) The sensor module according to any one of (1) to (4), wherein the first member has a cylindrical shape.

[0076] (6) A sensor module described in any of (1) to (5), wherein the first member has a cylindrical shape with a central axis extending in the front-to-rear direction, the first member has a lower portion located below the central axis and an upper portion located above the central axis, the upper portion is elastically deformable downward and the lower portion is elastically deformable upward, and the sensor and the second member are aligned in the vertical direction.

[0077] (7) The sensor module described in (6), wherein the upper portion includes a first contact portion located to the right of the central axis and a second contact portion located to the left of the central axis, and when the first member is elastically deformed, the first contact portion and the second contact portion come into contact with the second member.

[0078] (8) A sensor module described in any of (1) to (7), wherein the first member has a cylindrical shape with a central axis extending in the front-to-rear direction, the first member has a right portion located to the right of the central axis and a left portion located to the left of the central axis, the right portion is elastically deformable in the left direction, and the left portion is elastically deformable in the right direction, and the sensor and the second member are aligned in the vertical direction.

[0079] (9) A sensor module described in any of (1) to (8), wherein the first member has a lower portion located below the central axis and an upper portion located above the central axis, the upper portion includes a first contact portion located to the right of the central axis and a second contact portion located to the left of the central axis, and when the first member is elastically deformed, the first contact portion and the second contact portion come into contact with the second member.

[0080] (10) The sensor module according to (1), wherein the first member is in contact with the second member.

[0081] (11) The sensor module according to (10), wherein the second member is located between the first member and the sensor.

[0082] (12) The sensor module according to any one of (1) to (11), wherein the sensor is located inside the second member.

[0083] (13) The sensor module according to any one of (1) to (12), wherein the second member has a vibration-damping effect.

[0084] (14) The sensor module according to any one of (1) to (9), further including a support member that supports the second member and the sensor.

[0085] (15) The sensor module according to (14), wherein the support member is fixed to the inner circumferential surface.

[0086] (16) The sensor module described in any one of (1) to (9), wherein the first member has a cylindrical shape with a central axis extending in the front-rear direction, the first member is symmetrical about the central axis, and the second member and the sensor are located within the first member.

[0087] 1, 1a, 1b1, 1b2, 1c, 1d, 1e, 1f, 1g1, 1g2: sensor modules 10, 10b1, 10b2, 10c, 10d, 10g1, 10g2: first members 12, 12e: second members 13: sensor

Claims

1. A first member; a second member having a Young's modulus lower than that of the first member; a sensor that detects deformation of the second member, the sensor being in contact with the second member; Equipped with a distance between the first member and the sensor is greater than a distance between the first member and the second member; The first member is elastically deformable, When the first member is not elastically deformed, the second member is spaced apart from the first member. Sensor module.

2. When the first member elastically deforms, the second member comes into contact with the first member. The sensor module according to claim 1 .

3. The first member has a cylindrical shape including an inner circumferential surface and an outer circumferential surface, the second member and the sensor are located within the first member; When the first member is elastically deformed, the second member comes into contact with the inner circumferential surface. The sensor module according to claim 1 or 2.

4. The first member is cylindrical. The sensor module according to claim 1 or 2.

5. The first member has a cylindrical shape having a central axis extending in a front-rear direction, the first member has a lower portion located below the central axis and an upper portion located above the central axis, The upper portion is elastically deformable downward, and the lower portion is elastically deformable upward; The sensor and the second member are aligned in the vertical direction. The sensor module according to claim 1 or 2.

6. The upper portion includes a first contact portion located to the right of the central axis and a second contact portion located to the left of the central axis, When the first member is elastically deformed, the first contact portion and the second contact portion come into contact with the second member. The sensor module according to claim 5 .

7. The first member has a cylindrical shape having a central axis extending in a front-rear direction, the first member has a right portion located to the right of the central axis and a left portion located to the left of the central axis, The right portion is elastically deformable in a left direction, and the left portion is elastically deformable in a right direction, The sensor and the second member are aligned in the vertical direction. The sensor module according to claim 1 or 2.

8. The first member has a cylindrical shape having a central axis extending in the front-rear direction, the first member has a lower portion located below the central axis and an upper portion located above the central axis, The upper portion includes a first contact portion located to the right of the central axis and a second contact portion located to the left of the central axis, When the first member is elastically deformed, the first contact portion and the second contact portion come into contact with the second member. The sensor module according to claim 1 or 2.

9. The first member is in contact with the second member. The sensor module according to claim 1 .

10. The second member is located between the first member and the sensor. The sensor module according to claim 9.

11. The sensor is located within the second member. The sensor module according to claim 1 or 2.

12. The second member has a vibration-proof effect. The sensor module according to claim 1 or 2.

13. The sensor module further includes a support member supporting the second member and the sensor. The sensor module according to claim 1 or 2.

14. The first member has a cylindrical shape including an inner circumferential surface and an outer circumferential surface, The support member is fixed to the inner circumferential surface. The sensor module according to claim 13.

15. The first member has a cylindrical shape having a central axis extending in a front-rear direction, The first member is symmetrical about the central axis line, the second member and the sensor are located within the first member; The sensor module according to claim 1 or 2.

16. A first member, a second member having a Young's modulus lower than that of the first member; a sensor that detects deformation of the second member, the sensor being in contact with the second member; Equipped with a distance between the first member and the sensor is greater than a distance between the first member and the second member; The first member is elastically deformable, When the first member is elastically deformed, the second member comes into contact with the first member. Sensor module.

17. A first member, a second member having a Young's modulus lower than that of the first member; a sensor that detects deformation of the second member, the sensor being in contact with the second member; Equipped with a distance between the first member and the sensor is greater than a distance between the first member and the second member; The first member has a cylindrical shape including an inner circumferential surface and an outer circumferential surface, the second member and the sensor are located within the first member; When the first member is elastically deformed, the second member comes into contact with the inner circumferential surface. Sensor module.

18. A first member, a second member having a Young's modulus lower than that of the first member; a sensor that detects deformation of the second member, the sensor being in contact with the second member; Equipped with a distance between the first member and the sensor is greater than a distance between the first member and the second member; The first member has a cylindrical shape having a central axis extending in a front-rear direction, the first member has a lower portion located below the central axis and an upper portion located above the central axis, The upper portion is elastically deformable downward, and the lower portion is elastically deformable upward; The sensor and the second member are aligned in the vertical direction. Sensor module.

19. A first member, a second member having a Young's modulus lower than that of the first member; a sensor that detects deformation of the second member, the sensor being in contact with the second member; Equipped with a distance between the first member and the sensor is greater than a distance between the first member and the second member; The first member has a cylindrical shape having a central axis extending in a front-rear direction, the first member has a right portion located to the right of the central axis and a left portion located to the left of the central axis, The right portion is elastically deformable in a left direction, and the left portion is elastically deformable in a right direction. Sensor module.

20. A first member, a second member having a Young's modulus lower than that of the first member; a sensor that detects deformation of the second member, the sensor being in contact with the second member; Equipped with a distance between the first member and the sensor is greater than a distance between the first member and the second member; The first member has a cylindrical shape having a central axis extending in a front-rear direction, the first member has a lower portion located below the central axis and an upper portion located above the central axis, The upper portion includes a first contact portion located to the right of the central axis and a second contact portion located to the left of the central axis, When the first member is elastically deformed, the first contact portion and the second contact portion come into contact with the second member. Sensor module.