Sensor and method

Abstract

To enable measurement in the same state as far as possible.SOLUTION: A sensor 1 includes: a body 11 that is equipped with a piezoelectric element 4 for detection, and a hosing 2 storing the piezoelectric element 4 and having a contacting portion 2b contacting a measurement object; and an accessory portion 12 that has a platy member 12a with a flat surface, and a deforming member 12b provided on the opposite surface to a flat surface of the platy member 12a and deforming so as to conform to a shape of an installation surface. The deforming member 12b has a bag body, and granular articles provided in the bag body.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sensor and method for detecting vibrations. [Background technology]

[0002] The applicant has filed an application for an invention for identifying the direction of movement of a moving object using a sensor that detects vibrations (see Patent Document 1). FIG. 11 is a cross-sectional view showing a conventional vibration sensor. Sensor 101 includes a substantially cylindrical housing 102. Housing 102 houses weight 105 (described later) and other components. Housing 102 defines the outer shape of sensor 101. A substantially cylindrical protrusion 102a that protrudes downward is provided on the lower surface (bottom surface) of housing 102. A convex contact portion 102b is provided at the tip of protrusion 102a for bringing sensor 101 into contact with a measurement target (e.g., a road). For example, contact portion 102b has a substantially conical shape and a pointed tip. Vibrations transmitted to contact portion 102b are transmitted to piezoelectric element 104 (described later), and sensor 101 detects (measures) the vibrations using piezoelectric element 104.

[0003] Furthermore, legs 103 for supporting sensor 101 extend in the vertical direction from the lower surface (bottom surface) of housing 102. Legs 103 are, for example, extendable in the vertical direction, and by extending and contracting legs 103 in the vertical direction, sensor 101 can be stably installed on the road that is the measurement target.

[0004] The piezoelectric element 104 (detection element) is disposed inside the housing 102. Specifically, the piezoelectric element 104 is disposed on the bottom surface (lower surface) inside the protruding portion 102a of the housing 102. The piezoelectric element 104 has, for example, a flat, approximately disk shape. A weight 105 for applying a compressive load to the piezoelectric element 104 is disposed above the piezoelectric element 104. The weight 105 generates a voltage in the piezoelectric element 104 by applying a compressive load. The weight 105 has, for example, a substantially cylindrical shape. At least the lower half of the weight 105 is located inside the protruding portion 102a, but the upper part of the weight 105 protrudes from the protruding portion 102a. The piezoelectric element 104 and the weight 105 are disposed side by side in the vertical direction, i.e., in the direction of gravity. Specifically, the piezoelectric element 104 and the weight 105 are arranged side by side in the direction of gravity so that the load of the weight 105 is applied to the piezoelectric element 104 .

[0005] In conventional sensors 101, contact part 102b (point) that directly picks up vibrations is installed on the road, which is the measurement target. However, the asphalt that makes up the road has unevenness, and when installing sensor 101, the worker does not know whether to place it on a sharp (convex) spot, a concave spot, or a flat spot. Furthermore, if contact part 102b is installed on a sharp spot, the measurement results will change compared to when it is placed on a flat spot. In addition, because the tip of contact part 102b is made of resin, if it comes into direct contact with the asphalt, it will wear out, which may affect the measurement results. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-060264 Summary of the Invention [Problem to be solved by the invention]

[0007] As mentioned above, conventional sensors could not perform measurements under the same conditions depending on the installation location, which could result in different measurement results.

[0008] The object of the present invention is to make it possible to perform measurements under the same conditions as much as possible. [Means for solving the problem]

[0009] The sensor of the first invention is characterized by comprising a main body having a detection element and a housing that houses the element and has a contact portion for contacting the element with the object to be measured, and an accessory having a plate-shaped member with a flat surface and a deformable member that is provided on the surface opposite the flat surface of the plate-shaped member and deforms according to the shape of the installation surface.

[0010] In the present invention, the sensor includes an attachment having a plate-like member with a flat surface and a deformable member provided on the surface opposite the flat surface of the plate-like member, which deforms according to the shape of the installation surface. Therefore, by placing the attachment between the contact portion of the main body and the measurement object, even if the measurement object has an uneven shape, the sensor can perform detection in a flat state. This allows measurement to be performed in as consistent a state as possible.

[0011] A sensor of a second invention is the sensor of the first invention, characterized in that the deformable member has a bag body and granular material provided in the bag body.

[0012] In the present invention, the deformable member has granular materials, so that even if the measurement target (for example, a road) has unevenness, the granular materials allow the deformable member to conform to the unevenness.

[0013] A sensor according to a third aspect of the present invention is the sensor according to the second aspect of the present invention, characterized in that the particulate matter is glass beads.

[0014] A sensor according to a fourth aspect of the present invention is the sensor according to any one of the first to third aspects of the present invention, wherein the plate-like member has a recess having a shape corresponding to the contact portion.

[0015] In the present invention, the plate-like member has a recess having a shape corresponding to the contact portion, thereby allowing the contact portion to be positioned at a fixed position.

[0016] A sensor according to a fifth aspect of the present invention is the sensor according to any one of the first to fourth aspects of the present invention, wherein the contact portion has a convex shape.

[0017] A sensor according to a sixth aspect of the present invention is the sensor according to any one of the first to fifth aspects of the present invention, wherein the contact portion has a cone shape.

[0018] A sensor according to a seventh aspect of the present invention is the sensor according to any one of the first to sixth aspects of the present invention, further comprising legs extending from the bottom surface of the housing for supporting the sensor itself.

[0019] The sensor of an eighth invention is the sensor of the seventh invention, characterized in that the legs are extendable.

[0020] A sensor according to a ninth aspect of the present invention is the sensor according to any one of the first to eighth aspects of the present invention, characterized in that the element is a piezoelectric element.

[0021] The method of the 10th invention is characterized in that the object to be measured is measured via an attachment having a plate-like member with a flat surface placed on the object to be measured and a deformable member provided on the surface opposite the flat surface of the plate-like member and deforming in accordance with the shape of the installation surface.

[0022] According to the present invention, measurements are performed via an attachment having a plate-shaped member with a flat surface and a deforming member provided on the surface opposite the flat surface of the plate-shaped member and which deforms according to the shape of the installation surface, so that measurements can be performed in the same conditions as much as possible. [Effects of the Invention]

[0023] According to the present invention, measurements can be performed under the same conditions as much as possible. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a cross-sectional view showing a sensor according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram showing the measurement results when the contact portion is brought into contact with a sharp location. [Figure 3] FIG. 10 is a diagram showing the measurement results when the contact portion is brought into contact with a flat surface. [Figure 4] 4 is a diagram in which the measurement results shown in FIG. 2 and the measurement results shown in FIG. 3 are superimposed. [Figure 5] FIG. 10 is a diagram showing the measurement results when a deformable member is placed on a sharp location and measurement is performed through the deformable member. [Figure 6] FIG. 10 is a diagram showing the measurement results when the deformable member is placed on a flat surface and measurement is performed through the deformable member. [Figure 7] 7 is a diagram in which the measurement results shown in FIG. 5 and the measurement results shown in FIG. 6 are superimposed. [Figure 8] FIG. 10 is a diagram showing the measurement results when an attachment is placed at a sharp location and measurement is performed through the attachment. [Figure 9] FIG. 10 is a diagram showing the measurement results when the attachment is placed on a flat surface and measurement is performed through the attachment. [Figure 10] This is a diagram in which the results shown in FIG. 8 and the results shown in FIG. 9 are superimposed. [Figure 11] FIG. 1 is a cross-sectional view showing a conventional sensor.

[0025] An embodiment of the present invention will now be described. Fig. 1 is a cross-sectional view showing a sensor 1 according to an embodiment of the present invention. The sensor 1 is placed, for example, on a road 201 that is a measurement target, and detects (measures) vibrations occurring on the road 201 that is the measurement target.

[0026] The sensor 1 includes a main body 11 and an attachment 12. The main body 11 includes a substantially cylindrical housing 2. The housing 2 houses a weight 5, which will be described later, and the like. The housing 2 defines the outer shape of the main body 11. A substantially cylindrical protrusion 2a that protrudes downward is provided on the lower surface (bottom surface) of the housing 2. A convex contact portion 2b is provided at the tip of the protrusion 2a for bringing the main body 11 into contact with the measurement target (for example, a road). Specifically, the contact portion 2b is conical (pyramidal). Vibrations transmitted to the contact portion 2b are transmitted to a piezoelectric element 4, which will be described later, and the main body 11 detects (measures) the vibrations using the piezoelectric element 4.

[0027] Furthermore, legs 3 extend vertically from the lower surface (bottom surface) of the housing 2 to support the main body 11. The legs 3 are, for example, extendable in the vertical direction, and the main body 11 can be stably installed on the road that is the measurement target by extending and contracting the legs 3 in the vertical direction.

[0028] The piezoelectric element 4 (detection element) is disposed inside the housing 2. Specifically, the piezoelectric element 4 is disposed on the bottom surface (lower surface) inside the protruding portion 2a of the housing 2. The piezoelectric element 4 has, for example, a flat, approximately disk shape. A weight 5 for applying a compressive load to the piezoelectric element 4 is disposed above the piezoelectric element 4. The weight 5 generates a voltage in the piezoelectric element 4 by applying a compressive load. The weight 5 has, for example, a substantially cylindrical shape. At least the lower half of the weight 5 is located inside the protruding portion 2a, but the upper part of the weight 5 protrudes from the protruding portion 2a. The piezoelectric element 4 and the weight 5 are disposed side by side in the vertical direction, i.e., in the direction of gravity. Specifically, the piezoelectric element 4 and the weight 5 are disposed side by side in the direction of gravity so that the load of the weight 5 is applied to the piezoelectric element 4.

[0029] In this embodiment, the shape of the housing 2 is substantially cylindrical, and the shape of the weight 5 is also substantially cylindrical accordingly, but for example, the housing 2 and the weight 5 may be prisms such as triangular prisms. In other words, the shape is not important.

[0030] The attachment 12 includes a plate-shaped member 12a and a deformable member 12b. The surface of the plate-shaped member 12a is flat. Although not shown, the plate-shaped member 12a has a recessed portion shaped to correspond to the contact portion 2b of the main body 12. The deformable member 12b is provided on the surface opposite the flat surface of the plate-shaped member 12a. The deformable member 12b deforms according to the shape of the installation surface (in this embodiment, the road 201). The deformable member 12b includes a bag body and granular material provided within the bag body. In this embodiment, the granular material is, for example, glass beads. The granular material is not limited to glass beads, but may be ceramic beads, plastic beads, metal beads, etc. Note that for special measurements, such as when high frequencies need to be canceled out during measurements, elastic materials such as rubber beads can be used, but this is not preferred because absorbing vibrations may alter the results.

[0031] Furthermore, the deformable member 12b need not be made of a bag and granular material, as long as it can deform according to the shape of the installation surface. For example, it may be a solid material formed as an integral unit. Materials (elastic bodies) such as rubber that absorb vibrations are not suitable for the deformable member 12b because they absorb vibrations, but they can be used. As described above, the deformable member 12b is preferably made of a bag and granular material contained in the bag, but other materials, such as a clay-like material formed as an integral unit, can also be used as the deformable member 12b.

[0032] When measuring vibrations of a road 201 using the sensor 1, first, the accessory 12 is placed on the road 201. At this time, it is preferable to place the deformable member 12b so that it follows the unevenness of the road 201. Next, the main body 11 is placed so that the contact portion 2b is located within the recess of the accessory 12 (plate-like member 12a). Then, the vibrations of the road 201 are measured. That is, the main body 11 measures the measurement target (road 201) via the accessory 12.

[0033] FIG. 2 shows the measurement results when the contact portion 2b is brought into contact with a sharp location and measurement is performed. FIG. 3 shows the measurement results when the contact portion 2b is brought into contact with a flat location and measurement is performed. FIG. 4 shows a diagram in which the measurement results shown in FIG. 2 and the measurement results shown in FIG. 3 are superimposed. FIG. 5 shows the measurement results when the deformable member 12b is placed on a sharp location and measurement is performed through the deformable member 12b. FIG. 6 shows the measurement results when the deformable member 12b is placed on a flat location and measurement is performed through the deformable member 12b. FIG. 7 shows the measurement results shown in FIG. 5 and the measurement results shown in FIG. 6 are superimposed. FIG. 8 shows the measurement results when the attachment portion 12 is placed on a sharp location and measurement is performed through the attachment portion 12. FIG. 9 shows the measurement results when the attachment portion 12 is placed on a flat location and measurement is performed through the attachment portion 12. FIG. 10 shows a diagram in which the results shown in FIG. 8 and the results shown in FIG. 9 are superimposed. The vertical axis shows the vibration level [dB], and the horizontal axis shows the frequency [Hz].

[0034] As shown in Figures 2 to 4, when the contact portion 2b is brought into contact with the object to be measured, the measurement results differ depending on the installation location (pointed or flat). As shown in Figures 5 to 7, when the measurement is made via the deformable member 12b, the difference in the measurement results is improved compared to when the contact portion 2b is brought into contact with the object to be measured. As shown in Figures 8 to 10, when the measurement is made via the attachment portion 12b, the difference depending on the installation location is almost eliminated.

[0035] As described above, in this embodiment, the sensor 1 is equipped with an attachment 12 having a plate-like member 12a with a flat surface and a deformable member 12b that is provided on the surface opposite the flat surface of the plate-like member 12a and deforms according to the shape of the installation surface. Therefore, by placing the attachment 12 between the contact portion 2b of the main body 11 and the measurement object, even if the measurement object has an uneven shape, the sensor 1 can perform detection in a flat state. This allows measurement to be performed in the same state as much as possible.

[0036] Furthermore, by performing the measurement via the attachment 12, even if the contact part 12b is made of resin, it is possible to prevent wear and to minimize the influence on the measurement results.

[0037] In this embodiment, the deformable member 12b has granular matter (for example, glass beads). Therefore, even if the measurement target (for example, road 201) has unevenness, the granular matter allows the deformable member 12b to conform to the unevenness.

[0038] In this embodiment, the plate-like member 12b has a recessed portion having a shape corresponding to the contact portion 2b, thereby allowing the contact portion 2b to be positioned at a fixed position.

[0039] The above describes an embodiment of the present invention, but the forms to which the present invention can be applied are not limited to the above-described embodiment, and appropriate modifications can be made within the scope that does not deviate from the spirit of the present invention. [Industrial Applicability]

[0040] The present invention can be suitably employed in a sensor and method for detecting vibration. [Explanation of symbols]

[0041] 1 sensor 11 Main unit 12 Attachment 12a Plate-shaped member 12b Deformable member 2. Case 2a Protrusion 2b Contact part 3 legs 4 Piezo element (detection element) 5 weight

Claims

1. A sensor that is placed on a measurement object and detects vibrations occurring in the measurement object, a detection element; a housing having a protrusion that extends toward the measurement object when placed on the measurement object and has the element disposed on its bottom surface, and a contact portion that is provided at the tip of the protrusion and is used to contact the measurement object; the main body including a leg portion extending in the same direction as the protrusion portion and supporting the main body on the measurement object in the placed state; an attachment having a plate-like member with a flat surface and a deformable member provided on the surface of the plate-like member opposite the flat surface and deformed in accordance with the shape of the object to be measured; A sensor comprising:

2. A detection element; a main body including a housing that houses the element and has a contact portion for contacting the element with a measurement object; an attachment having a plate-like member with a flat surface and a deformable member provided on a surface opposite to the flat surface of the plate-like member, the deformable member being deformed according to the shape of the installation surface; Equipped with The sensor characterized in that the deformable member has a bag body and granular material provided in the bag body.

3. 3. The sensor according to claim 2, wherein the particles are glass beads.

4. 4. The sensor according to claim 1, wherein the plate-like member has a recess having a shape corresponding to the contact portion.

5. 5. The sensor according to claim 1, wherein the contact portion has a convex shape.

6. 6. The sensor according to claim 1, wherein the contact portion is cone-shaped.

7. The sensor according to claim 2 , further comprising legs extending from the bottom surface of the housing for supporting the sensor itself.

8. The sensor of claim 7, wherein the legs are extendable.

9. 9. The sensor according to claim 1, wherein the element is a piezoelectric element.

10. A method for detecting vibrations occurring in a measurement object by the sensor according to claim 2, comprising: A method for measuring a measurement object via the attachment.

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