JP2009244222A - Pressure detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure detector that has a spacer having elasticity disposed between a pair of detecting elements, detects the pressure applied to the detecting elements by detecting the displacement amount between the pair of plate-like detecting elements, and improves the accuracy of detecting small pressure. <P>SOLUTION: This pressure detector includes the pair of plate-like detecting elements 13 arranged facedly, spacers 6 having electricity interposed between facing surfaces 13a of the detecting elements 13, and a detecting means for detecting the displacement amount between the facing surfaces 13a of the pair of detecting elements 13. The pressure detector detects the pressure applied to the detecting elements by detecting the displacement amount with the detecting means. The contact parts of the spacers 6 with the facing surfaces 13a of the detecting elements 13 form projecting curved surfaces of circular arc shape in the cross sectional view. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pressure detection device that detects a pressure applied to a detection body by providing an elastic spacer between the pair of detection bodies and detecting a displacement amount between the pair of plate-like detection bodies.

A pair of plate-like detection bodies arranged opposite to each other, a spacer having elasticity between the opposing faces of the detection bodies, and a displacement amount between the opposing faces in the pair of detection bodies (amount of change in the distance between the opposing faces) And a pressure detecting device shown in Patent Documents 1 and 2 for detecting the pressure applied to the detection body from the correlation with the elasticity of the spacer by detecting the amount of displacement. It is publicly known.
Japanese Patent No. 3593184

However, the pressure detection device of the above document is formed so that the contact portion of the spacer with the opposing surface of the detection body forms a horizontal plane substantially parallel to the opposing surface, and the opposing surface of the detection body and the spacer are in planar contact. Because the distance between the detection bodies (between the opposing surfaces of the detection bodies) changes greatly by applying pressure on the detection bodies so as to deform the entire spacer, the accuracy of detecting small pressure is low. There is.
The present invention solves the above-described problems, and provides a pressure detection device that provides a spacer having elasticity between a pair of detection bodies and detects the pressure applied to the detection bodies by detecting the amount of displacement between the pair of plate-like detection bodies. An object of the present invention is to provide a pressure detection device with improved accuracy for detecting a small pressure.

  In order to solve the above problems, a pressure detection device according to the present invention firstly includes a pair of plate-like detection bodies 13 arranged to face each other, and an elastic spacer interposed between opposing faces 13a of the detection body 13. 6 and a detecting means for detecting the amount of displacement between the opposing surfaces 13a of the pair of detecting bodies 13, wherein the detecting means detects the pressure applied to the detecting body 13 by detecting the amount of displacement. 6 is formed so that the contact portion with the opposing surface 13a of the detector 13 in FIG.

  Secondly, the spacer 6 is characterized in that it is formed in a spherical or cylindrical shape having a substantially circular or elliptical shape in cross section.

  Third, a spherical or columnar spacer 6 is formed by superimposing members made of different materials from the central portion toward the outside so as to be substantially circular or elliptical in cross-sectional view.

  Fourthly, a plurality of spacers 6 are interposed between the pair of detection bodies 13.

  Fifth, some spacers 6 in the plurality of spacers 6 are made of a material different from other spacers 6.

  Sixth, a plurality of spacers 6 are provided so as to overlap in the stacking direction of the detectors 13.

  Seventhly, a plurality of pairs of detectors 13 are arranged in parallel in a plane.

  According to the pressure detection device of the present invention configured as described above, since the opposing surface of the detection body and the spacer contact each other in a dotted or band shape, even if the pressure applied to the detection body is small, The contact portion and the shape in the vicinity thereof are deformed to change the distance between the pair of detection bodies. This has the effect of improving the accuracy of detecting a small pressure.

  In addition, if a spherical or cylindrical spacer is formed by overlapping members of different materials from the central portion toward the outside so as to have a substantially circular or elliptical shape in cross section, the spacer can have desired characteristics. Has the effect of becoming possible.

  By constructing a part of the spacers from a material different from that of the other spacers, it is possible to easily change the amount of displacement between the sensing bodies relative to the pressure applied to the sensing bodies according to the purpose. effective.

  By arranging a plurality of pairs of detection bodies in parallel in a plane, there is an effect that the pressure distribution can be detected.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an exploded perspective view showing a configuration of a pressure detection device to which the present invention is applied, and FIG. 2 is a perspective view schematically showing a configuration of the pressure detection device.

  The pressure detection device 1 is provided between three base plates (lower layer plate 2, middle layer plate 3, upper layer plate 4) and base plates 2, 3, 4 arranged in a stacked manner, and the distance between the base plates 2, 3, 4. And a spacer 6 (cushion material) that maintains a predetermined distance, and a displacement amount detection means (detection means) that detects a displacement amount (amount of change in distance) between predetermined portions of the three base plates 2, 3, and 4. Yes. The lower surface (opposing surface 7) of the upper layer plate 4 opposes the upper surface (opposing surface 8) of the middle layer plate 3 substantially in parallel, and the lower surface (opposing surface 9) of the intermediate layer plate 3 faces the upper surface (facing surface 11) of the lower layer plate 2. ).

  Each of the base plates 2, 3, 4 is configured by a member that can be elastically deformed by a predetermined amount so as to transmit the pressure to the spacer 6 during pressurization. A plurality of strip-shaped (five in the illustrated example) electrode plates 12 (electrodes, electrode bodies) are provided in parallel to each other.

  The electrode plate 12 is also composed of a member that can be elastically bent and deformed by a predetermined amount so as to transmit the pressure to the spacer 6 during pressurization. The electrode plates 12 arranged on the middle layer plate 3 are arranged in a plane view crossing direction (orthogonal direction in the illustrated example) with respect to the electrode plates 12 arranged on the upper layer plate 4 and the lower layer plate 2. As described above, the overlapping portions (intersection portions) in plan view of the electrodes 12 stacked in the stacking direction are arranged in parallel in a matrix shape, and the intersection portions and the intersection portions of the base plates 2, 3, 4 are matched. The contact portions (capacitor constituent portions) each constitute a capacitor. In addition, the intersection part by the electrode 12 on the upper layer plate 4 and the electrode 12 on the middle layer plate 3 and the intersection part by the electrode 12 on the middle layer plate 3 and the electrode 12 on the lower layer plate 2 are arranged at substantially the same position in plan view. Each electrode 12 is configured to be formed. That is, the capacitor has a three-layer structure including the upper layer plate 4, the middle layer plate 3 and the lower layer plate 2.

  The spacer 6 is made of an insulating (dielectric) material having elasticity, and is formed into a substantially circular or substantially elliptical columnar shape in a sectional view. The plurality of spacers 6 are arranged in parallel in the base plate 2, 3, 4 formation direction so as to be parallel to each other.

  The displacement detection means detects (measures) the change in the distance of the capacitor component between the base plates 2, 3, 4 by detecting the change in the capacitance between the electrodes 12 described above during pressurization. The pressure applied to the portion is detected from the correlation between the change amount between the portions and the elastic force of the spacer 6. That is, a plate-like detection body 13 (detection unit) for detecting pressure is constituted by the intersection of the electrodes described above and the capacitor components of the base plates 2, 3, 4. , 4 is formed with a plurality of surfaces (opposing surfaces 13a) on which the detection bodies 13 are opposed to each other on the aforementioned facing surfaces 7, 8, 9, 11 side.

  Incidentally, in the illustrated example, the electrodes 12 are arranged in five rows on each of the upper layer plate 4 and the middle layer plate 3, and the electrodes 12 on the upper layer plate 4 and the electrodes 12 on the middle layer plate 3 are orthogonal to each other in plan view. As shown in FIG. 5, 25 pairs of a pair of detection bodies 13 are formed. As described above, since a plurality of pairs of the detection bodies 13 are provided and arranged in parallel in a plane, it is possible to detect the distribution of pressure applied to the upper surface 14 (detection surface) of the ascending plate 4. .

  In order to detect the amount of change in the capacitance of the capacitor as described above, this displacement amount detection means includes an oscillator 16 that applies an alternating voltage as an input signal to the electrodes 12 of the upper layer plate 4 and the lower layer plate 2, and the capacitance. And variable amount detection means 17 for detecting.

  Since the input signal is input to the variable amount detection means 17 and the voltage change of the intermediate layer plate 3 based on the input voltage is input as an output signal, the impedance of the capacitor can be obtained as an impedance by comparing the input signal with the output signal. Capacitance can be detected (measured), and the amount of change in capacitance is detected by performing this capacitance detection every predetermined time.

  Further, the displacement amount detection means includes an upper layer side input switching means 18 (input switching means, switching means) for switching to which of the plurality of electrodes 12 on the upper layer plate 4 an input signal from the oscillator 16 is input, and the oscillator 16. The lower layer side input switching means 19 (input switching means, switching means) for switching which of the plurality of electrodes 12 on the lower layer plate 2 is input and the lower layer plate 2 by inverting the input signal from the oscillator 16 An inverting amplifier 21 that inputs to the upper electrode 12, an output switching means 22 (switching means) that switches which of the plurality of electrodes 12 on the intermediate layer plate 3 is output to the variable amount detection means 17, And an amplifier 23 that amplifies an output signal from the electrode 12 and inputs the amplified signal to the variable amount detection means 17.

  The two input switching means 18 and 19 are synchronized, and are configured to input an input voltage to the electrodes 12 in the same column. For example, in the illustrated example, both the upper layer plate 4 and the lower layer plate 2 are in a state in which signals from the transmitter 16 are input to the electrodes 12 in two rows from the front side in FIG. As a result, the capacitor to be detected has a three-layer structure as described above, and is less susceptible to the effects of charges in the air, reducing the amount of noise contained in the output signal from the electrode 12 on the selected middle layer plate 3. In addition, the amount of noise included in the output signal can also be reduced by inverting the input signal by the inverting amplifier 21 and inputting it to the electrode 12 of the lower layer plate 2.

  In addition, the spacer 6 between the lower layer plate 2 and the lower layer plate 2 and the middle layer plate 3 may be omitted, and the capacitor to be detected may have a normal two-layer structure. In this case, noise cannot be reduced, but the structure can be simplified.

  In addition, it is only necessary to provide one displacement detection means, which is usually required for each pair of detectors 13 and 13, for each pressure detection device due to the switching action of the three switching means 18, 19, and 22. Thus, the configuration can be simplified. For example, in the illustrated example, an input signal is inputted to the electrodes 12 in the two columns (rows) from the front side in FIG. 1 of the upper layer plate 4 and the lower layer plate 2, and the electrodes in the two columns from the left side in FIG. Since 12 output signals are output to the variable amount detection means 17, the capacitance of the second capacitor from the left side and the second capacitor from the lower side in FIG. 2 is detected.

  Further, the electrodes 12 of the upper layer plate 4 and the lower layer plate 2 in a state where the input signal from the oscillator 16 is not input are grounded by the two input switching units 18 and 19 so that unnecessary noise is not included in the output signal. It has become.

Next, the configuration of the pair of detectors 13 and the spacer 6 will be described in detail.
FIG. 3 is a schematic view showing a state in which the spacer 6 is interposed between the pair of detection bodies 13. One or a plurality of spacers 6 are provided between the opposing surfaces 13 a of the pair of detectors 13. When a plurality of spacers 6 are provided, it is desirable to provide the spacers 6 between the detection bodies 13 with the same pitch and the same posture. As a result, it is possible to minimize an error in pressure detection caused by changing the pressing position.

  Since each spacer 6 is formed in a circular shape or an oval shape in cross section as described above, the contact portion with the facing surface 13a of the detection body 13 forms a convex curved surface having an arc shape in cross section. As a result, the spacer 6 comes into contact with the opposing surface 13a of the detection body 13 in a band shape. At this time, the adjacent spacers 6 and the spacers 6 and the base plates 2, 3, 4 side are fixed by an adhesive or the like, whereby the spacers 6 are held between the pair of detectors 13, 13.

  As described above, even when the detection body 13 and the spacer 6 are in partial contact with each other and the pressure applied to the detection body 13 is small, the spacer 6 is configured to be deformed immediately. In addition to the improvement, the spacer 6 can be formed of a highly durable material with a small amount of deformation during pressurization. Specifically, the spacer is constituted by a continuous foamed member that is responsive to contraction and expansion that restores the original shape in a short time.

Next, a configuration different from the above-described embodiment will be described with respect to six modified examples of the spacer.
FIG. 4 is a perspective view showing another example of the spacer 6. Spherical spacers having a substantially circular or elliptical cross-sectional shape are arranged in close contact with each other in a plurality of planes. By forming the spacer 6 in a substantially spherical shape in this way, the spacer 6 and the base plates 2, 3, 4 are brought into contact with each other in a dotted manner, so that the spacer 6 is deformed even when the pressure applied to the base plates 2, 3, 4 is small. be able to.

  FIG. 5 is a perspective view showing another example of the spacer 6. The columnar or spherical spacer 6 having a substantially circular or elliptical cross-sectional shape may be formed into a two-layer structure by overlapping members of different materials from the central portion toward the outside. In this example, the inside is made of a material 6a having low responsiveness (small displacement) and the outer peripheral portion is made of material 6b having high responsiveness (large displacement), and the spacer 6 has desired characteristics corresponding to the object to be detected. You can have it. In addition, you may make not only a two-layer structure but a multilayer structure.

  FIG. 6 is a perspective view showing another example of the spacer 6. Cylindrical spacers 6 may be overlapped in the stacking direction. In this example, three layers of the spacers 6 are overlapped, and the middle spacer 6 and the spacers 6 stacked above and below the spacer 6 are arranged so as to cross each other. By superposing the spacers 6 in the stacking direction in this way, it becomes possible to use as the spacer 6 a member that has a smaller amount of deformation during pressurization.

  FIG. 7 is a perspective view showing another example of the spacer 6. Of the plurality of spacers 6, a part of the spacers 6 may be formed of a member different from the other spacers 6, and these may be stacked. In this example, between the base plates 2, 3, and 4, spherical spacers 6 having a small displacement amount during pressurization are arranged vertically, and spacers 6 having a large displacement amount during pressurization are disposed therebetween. However, the spacer 6 in this case may be cylindrical or substantially spherical. In addition, in this case, the spacer 6 may not be laminated between the base plates 2, 3, and 4.

  FIG. 8 is a perspective view showing another fixing method of the electrode plate and the spacer. The electrode 12 may be directly fixed to the spacer 6 with an adhesive or the like without using the base plates 2, 3 and 4. In this case, the detection body 13 is configured only by the above-described intersections of the electrodes 12, and the opposite surface of the detection body 13 on the opposite surface side of the intersection of one electrode 12 with the intersection of the other electrode 12. 13a is formed.

Next, based on FIGS. 9 and 10, a configuration different from the above embodiment will be described for another embodiment.
FIG. 9 is a schematic view showing another embodiment of the present invention, and FIG. 10 is a cross-sectional view taken along line AA of FIG. The pressure detection device 1 includes two rectangular base plates 24 and 26 that are stacked and a spacer 6 that holds the pair of base plates 24 and 26 at a predetermined interval.

  One base plate 24 (pressure plate) is made of a conductor, a magnetic material (ferromagnetic material, paramagnetic material, diamagnetic material), or the like, and a detection surface 14 to which pressure is applied is formed on the upper surface side. The other base plate 26 (detection plate) is made of a flexible insulator such as a PET member. A primary coil 31 (applied coil) to which the AC voltage (input signal) from the oscillator 16 is amplified and applied to the lower surface side of the detection plate 26 by the amplifier 33 is generated on the upper surface side by a magnetic field change from the primary coil 31. Secondary coils 32 (detection coils) are provided.

  When the pressure is applied, the detection plate 24 bends toward the detection plate 26, so that the magnetic field from the primary coil 31 changes, and the mutual inductance between the primary coil 31 and the secondary coil 32 changes. By detecting the amount of change in the mutual inductance, the displacement amount detecting means detects (measures) the amount of change in the distance between the base plates 24 and 26, and from the correlation between the amount of change between the portions and the elastic force of the spacer 6. The pressure applied to that portion is detected. Specifically, an input signal from the oscillator 16 and an AC voltage (output signal) generated by the electromotive force of the secondary coil 32 are input to the variable amount detection unit 17 constituting the displacement amount detection unit, and the two signals The mutual inductance is detected by comparing. The output signal is amplified by the amplifier 23 and input to the variable amount detection means 17.

  As described above, the detection plate 24 and the detection plate 26 constitute the pair of detection bodies 13 and 13 described above. Incidentally, the pressure detection device 1 may be configured so that the pressure distribution can be detected by arranging the pair of detectors 13 and 13 in a plane on the same plane as in the above-described embodiment.

  In the above description, the example in which the detection surface 14 of the pressure detection device 1 is directed upward has been described. However, the posture of the pressure detection device 1 may be changed so that the detection surface 14 faces the other direction.

It is a disassembled perspective view which shows the structure of the pressure detection apparatus to which this invention is applied. It is a perspective view which shows the structure of this pressure detection apparatus typically. It is a schematic diagram of a pair of detection body which interposed the spacer. It is a perspective view which shows the other example of a spacer. It is sectional drawing which shows the other example of a spacer. It is a perspective view which shows the other example of a spacer. It is a side view which shows the other example of a spacer. It is a perspective view which shows the other adhering method of an electrode plate and a spacer. It is the schematic which shows other embodiment of the pressure detection apparatus of this invention. It is AA sectional drawing of FIG.

Explanation of symbols

6 Spacer (cushion material)
13 Detector 13a Opposite surface

Claims (7)

  A pair of plate-like detection bodies (13) arranged to face each other, an elastic spacer (6) interposed between the opposed surfaces (13a) of the detection body (13), and a pair of detection bodies (13) Detecting means for detecting the amount of displacement between the opposing surfaces (13a) in the pressure detector, wherein the detecting means detects the pressure applied to the detection body (13) by detecting the amount of displacement, in the spacer (6) The pressure detection apparatus shape | molded so that a contact part with the opposing surface (13a) of a detection body (13) may make a convex curved surface of cross-section circular arc shape.   The pressure detection device according to claim 1, wherein the spacer (6) is formed in a spherical or cylindrical shape having a substantially circular or elliptical shape in cross section.   The pressure detecting means according to claim 2, wherein a spherical or cylindrical spacer (6) is formed by superimposing members of different materials from the central portion toward the outside so as to be substantially circular or elliptical in cross section.   The pressure detection device according to claim 1, 2 or 3, wherein a plurality of spacers (6) are interposed between the pair of detection bodies (13).   The pressure detecting device according to claim 4, wherein a part of the spacers (6) is made of a material different from that of the other spacers (6).   The pressure detection device according to claim 4 or 5, wherein a plurality of spacers (6) are provided so as to overlap in the stacking direction of the detectors (13).   The pressure detection device according to claim 1, 2, 3, 4, 5 or 6, wherein a plurality of pairs of detection bodies (13) are arranged in parallel in a plane.

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