TW201231937A - Electrostatic capacity-type displacement sensor and proportional control valve having electrostatic capacity-type displacement sensor - Google Patents

Abstract

The present invention provides an electrostatic capacity-type displacement sensor for measuring linear displacement of a measurement subject. This electrostatic capacity-type displacement sensor comprises a first member having a cylinder electrode in the shape of a cylinder the central axis of which is parallel to a straight line, and a second member having a tubular outer electrode provided in a state electrically insulated from the cylinder electrode at the outer side of the cylinder electrode. The outer electrode has at least one pair of electrodes circumferentially separated from and facing one another, and the cylinder electrode is electrically insulated from the circuit connected to the outer electrode. The first and second members move relative to each other on the straight line with the displacement of the measurement subject, and the electrostatic capacity between the at least one pair of outer electrodes changes in accordance with this movement.

Description

201231937 VI. INSTRUCTIONS: [Ming jin genus genius cold shell: ^ j FIELD OF THE INVENTION The present invention relates to a capacitive displacement sensor, in particular to a use of the change in the opposing area of the electrode A displacement sensor that causes a change in electrostatic capacitance. BACKGROUND OF THE INVENTION In a device towel having a component called a fluid control valve or actuating a movement of 0 π < word 桎 1 line, there is a displacement sensor having a displacement of m 彳. The displacement sensor for such a use can utilize a contact potential ϋ (Patent Document 1) or a differential transformer type displacement sensor, or a magnetic body such as a holster, because the displacement amount of the measurement object is large. The non-contact displacement sensor = m has a simple structure, and the capacitive displacement sensor has been used for other purposes. The p-type displacement sensor utilizes the relative movement of the opposite electrode. The change of the static capacitance, the measurement of the change of the measurement object == the displacement of the measurement object - the detection of the opposite direction of the opposite electrode ^: the change of the open distance is called the change of the electrostatic capacitance. The opposite-surface type of electrostatic capacitance type displacement sensor (the patent uses the opposite direction as shown in Fig. 15, which has the effect of the opposite direction), because the point of the counter electrode is as much as possible. ϋ In this method, the region of the figure 17 is solved by Z, and the sensitivity of f is improved. Therefore, the measurement error caused by the error of the first large deviation is 201231937. As a result, a strict manufacturing tolerance and measurement sensitivity are generated. The problem of trade-offs. On the other hand, the way to change the distance As shown in Fig. 16, the electrostatic capacitance type displacement sensor has the advantage that the measurement error caused by the error related to the relative position parallel to the opposing surface between the counter electrodes is linear. However, as shown in Fig. 17, the relationship between the displacement d of the measuring object and the electrostatic capacitance (C = ε >< S/d) is nonlinear, and there is a large change such as the region Z2. The extremely difficult problem is measured in the region of the bit amount (stroke). On the other hand, the measurement method that does not utilize the change of the electrostatic capacitance is proposed, but the measurement method based on the communication state between the counter electrodes using the capacitive coupling is also proposed. The sensor (Patent Documents 4 and 5) is used as a sensor using a static capacitance. In this embodiment, a plurality of counter electrodes having voltages different in phase from each other are applied to the point, and the object is measured. The displacement and the complex counter electrode produce the strongest capacitive coupling, and the measurement is performed accordingly. Since the method can be used for the non-contact switching circuit, the measurement can be performed without affecting the movement of the measuring object. However, this method requires a complicated electrode pattern to be formed on the curved surface for switching the circuit, and has a problem that the wiring or the circuit is complicated. PRIOR ART DOCUMENT Patent Document Patent Document 1 Japanese Patent Laid-Open Publication No. 2010-152763 Patent Document 2 Patent Publication No. 01-196011 Patent Document 3 曰 Patent Publication No. 03-123814

Japanese Patent Laid-Open Publication No. Hei 08-166204 C Patent Literature No. Hei 08-166204 C. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION The present invention has hitherto utilized a change in electrostatic capacitance. In the sensor, there is a problem of a trade-off between the measurable displacement amount and the assembly tolerance of the counter electrode. On the other hand, with capacitive coupling, in the form of a non-contact switching circuit, there are problems such as formation of a complicated electrode pattern on a curved surface, wiring or circuit recombination. The present invention has been made in order to solve at least a part of the above-mentioned problems, and an object of the invention is to provide a technique for measuring displacement of a measuring object by means of a simple capacitance using a static capacitance. Means for Solving the Problem The following is a description of the means for solving the above-mentioned problems, and the like, as needed, and the like. Means 1. A static capacitance type displacement sensor for measuring a displacement on a straight line of a measurement object, comprising: a first member and a second member, the first member having a cylindrical cylindrical electrode, the cylinder The cylindrical electrode has a central axis parallel to the straight line; the second member has a cylindrical outer electrode that is electrically insulated from the cylindrical electrode on the outer side of the cylindrical electrode. The outer electrode has a circumferential direction and is opposed to at least one pair of electrodes, wherein the cylindrical electrode is electrically insulated from a circuit connected to the outer electrode, and the first member and the 201231937 member are subjected to the measurement target. The displacement is relatively relatively long on the straight line. The electrostatic capacitance between the outer electrodes is changed in response to the aforementioned movement. The means 1 comprises an outer electrode which is provided on the outer side of the cylindrical electrode and is electrically insulated from the cylindrical electrode, and the electrostatic capacitance is measured! The displacement of the object changes one of the electrodes. The change in the electrostatic capacitance is caused by the relative displacement of the outer electrode and the round electrode with the displacement of the measuring object, thereby causing a change in the opposing area between the outer electrode and the cylindrical electrode. Since the cylindrical electrode and the outer electrode are circumferentially opposed to each other, the cylindrical electrode is electrically insulated from the circuit connected to the outer electrode, so even if the cylindrical electrode and the outer electrode are separated from each other by the distance between the opposing faces, the static electricity is caused. The change in capacity can still be offset. Thereby, the problem of the trade-off between the measurable displacement amount and the assembly tolerance A of the counter electrode can be solved, and the measurable displacement amount can be expanded without excessively demanding the assembly tolerance. Furthermore, since the positional relationship between the cylindrical electrode, i.e., the inner surface of the outer electrode, does not change, the measurement of various displacements of the valve body or actuator of (4) is suitable. The one-handed ^2. The electrostatic capacitance type displacement sensor according to the first aspect, wherein the one side electrode is divided into two by a plane including a direction of the displacement of the measuring object, and one of the opposite directions Electrode. The better gossip is derived from the inventor's analysis and experiment and the outer electrode is derived: the column electrode ^ Bu: ^ The invention of the inventor's experiment 1 and the measurement of the direction of the wrong money, and the opposite direction + I. The eccentric direction of the θ has an outer electrode relative to the damage

S 6 201231937 The meaning of the relative direction of the direction of the face. a means 3_ as means! Or a static capacitance type displacement sensor according to claim 2, wherein the MW member has a connection portion for connecting to the measurement target, and the second member has a connection to the at least one pair of outer electrodes, respectively, and the second forward The outside of the member penetrates at least the pair of conductive portions of the second member. Since the means 3 is provided with an electrode that is connected to the outside from the inside to the outside of the measurement object-co-located position, it is possible to avoid deformation of the wiring of the object displacement, and it is not necessary to consider the design of the wiring. And, by eliminating the reliability of the line sensor. * The moving part can also improve the static capacitance type displacement sensor described in the above == means 1, wherein the front = the front (four) pole and the front (four) (four) pole surrounded by the area, the area is non-compressive The dielectric fluid is filled. Since the means 4 is filled with the outer electrode and the dielectric fluid of the contraction, the space surrounded by the static electrode can be increased by the non-pressure using various dielectric fluids as the non-compressibility. It can refer to a fluid that is more dielectric than conductive. ^ Current body. The dielectric current system means 5. The second member of the static lightning system described in the fourth aspect further has a compensation electric displacement sensor, wherein the outer peripheral electrode of the outer electrode is provided with a different diameter from each other. _Slightly = the opposite of the dielectric, the aforementioned - for the fixed opposite power = = the area surrounded by the column electrode and the current body. In the communication hole of the region, the means 5 includes a compensation capacitor having a pair of opposite electrodes arranged in the outer circumferential direction of the outer electrode and opposed to each other with a diameter interposed therebetween. The compensating capacitor shares the dielectric fluid by communicating with a region surrounded by the outer electrode and the cylindrical electrode and a communicating hole of a region sandwiched by the pair of fixed counter electrodes. Thereby, the compensation capacitor can be mounted without making the size of the measurement object in the displacement direction too large, and the error of the measurement displacement due to the change in the dielectric load can be compensated. [6] The static capacitance type displacement sensor according to the first aspect, wherein the second member has a surface (four), and the static capacitance type displacement sensor is provided with a state of being in a state of being electrically H a movement range value cover (1) between the electrode (four) electrode and the sensor body, and a metal tubular shielding member of the outer electrode and the cylindrical electrode The shielding member is electrically grounded. In the means 6 when the first member and the second member move relative to each other, the metal cylindrical shielding member covers both the outer electrode and the cylindrical electrode. Therefore, when detecting the electrostatic capacitance, even if there is external disturbance such as a sensor body that contacts a second member having the outer electrode, the influence of (4) the main cause of external disturbance can be reduced. Further, the stray capacitance generated between the outer electrode or the round electrode and the sensor body can be removed by the cylindrical shield member that is grounded. Therefore, the main cause of the instability of the electrostatic capacitance can be reduced, and the detection of the electrostatic capacitance can be performed stably. The static capacitance type displacement sensor according to the sixth aspect, wherein the second member has at least one pair of the outer electrodes, and the outer member penetrates at least one of the second members toward the outer side of the second member For the conductive part,

S 8 201231937 The outer part of the front member is penetrated through the second structure "%" is also covered by the above-mentioned tube, and the conductive portion and the cylindrical shielding member are outside the second member. a portion of the circuit board having the back surface facing the electrode side, and a metal film electrically connected to the grounding circuit formed on the circuit board on the front surface of the front (four) germanium substrate. The means 7 is a cylindrical shielding member and The metal film surrounds the electrode part and the electric circuit. P damage' can obtain a wider shielding effect. Therefore, the amount of money can be less due to external interference (4), and also contribute to the deletion of stray electricity valley. In addition, when the circuit board is mounted at a distance from the second member, even if the conductive portion protrudes to the outside of the second member, the external interference can be reduced. The cause of the cause is 5. The stray capacitance generated between the protruding conductive portions can be reduced by the cylindrical member or the metal film respectively connected to the ground. Therefore, the increase of the stray capacitance can be suppressed even if Separate the circuit board = The structure can also be detected in a state in which the static capacitance is stabilized. The U-type proportional control valve is used to control the flow of the dielectric fluid, and the Z 3 has a static capacitance type displacement of the means 4 or 5. a valve body having a valve body '''''''''''''''''''''''''''''''''''''''' The dielectric material is fed to the flow path of the front ship. Since the hand 1 and 8 use the fluid of the control object as the dielectric fluid, it can be easily used without the special money path or storage tank for using the dielectric fluid. In addition, in the present specification, the proportional control valve has the meaning of the broad 201231937. For example, as long as it is measurable for measuring the valve opening degree, for example, a mixing valve for controlling the mixing ratio is also included. The invention can not only realize the static capacitance type displacement sensor or the vacuum control valve and other proportional control valves, for example, the cylinder, the actuator and the spool valve of the static capacitance type displacement sensor can be realized. Chemical BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a configuration of a valve fully closed state of a vacuum control valve 4 of the first embodiment. Fig. 2 is a view showing a half-open state of a vacuum control valve 4 of the second embodiment. Fig. 3 is a cross-sectional view showing the structure of the amount of rise sensor 1 。. Fig. 4 is an external view showing the end of the amount of rise sensor 1 第. Fig. 5 shows the amount of rise sensing Fig. 6 is a perspective view showing the structure of the counter electrode of (9) for the amount of rise sensing. Fig. 7 is a graph showing the calculation formula of the electrostatic capacitance of the amount of rise sensor (10). Fig. 8 is a comparison The static capacitance of the cylindrical electrode and the outer electrode is not shown by the theoretical value. Fig. 9 is a graph showing the measurement error caused by the eccentricity of the cylindrical electrode and the outer electrode. ΔFig. 10 shows the vacuum of the i-th modification. A cross-sectional view of the structure of the valve fully closed state of the control valve*. Figure 11 shows the dielectric constant changes in response to the temperature of the dielectric fluid.

S 10 201231937 Chart. Fig. 12 is a cross-sectional view showing the structure of the valve fully closed state of the vacuum control valve 40b of the second modification. Fig. 13 is a partial cross-sectional view showing the structure of the dielectric fluid control valve 40c of the third modification. Figs. 14(a) and 14(b) are cross-sectional views showing the sensor installation side of the bobbin valve 100 of the second embodiment. Fig. 15 is a view showing a state in which the opposing area of the counter electrode of the prior art is changed. Fig. 16 is a view showing a state in which the distance between the opposing electrodes is changed in the prior art. Fig. 17 is a graph showing the relationship between the separation distance of the counter electrode and the electrostatic capacitance of the prior art. I. Embodiments for carrying out the invention. First Embodiment Hereinafter, a first embodiment of the present invention will be specifically described with reference to the drawings. In the present embodiment, the vacuum control valve 40 used in the manufacturing line of a semiconductor device or the like is specifically realized, and the description will be made based on Figs. 1 to 6 . Fig. 1 is a cross-sectional view showing the structure of the valve fully closed state of the vacuum control valve 40 of the first embodiment. Fig. 2 is a cross-sectional view showing the structure of the valve half-open state of the vacuum control valve 40 of the first embodiment. The vacuum control valve 40 includes a valve body 41, an on-off valve 30, an actuator 42, and a lift amount sensor 100. In the valve 201231937, a vacuum container (not shown) and a vacuum are formed. The flow path is used to connect the upstream side flow path 81' on the vacuum container side and the downstream side flow path 82 to be connected to the vacuum system. The switch 30 has a function of a flow path between the upstream side stream _ and the downstream side flow path 82 and a function of adjusting the conductance by operating the opening degree of the flow path. The switch valve body 31 has a poppet valve body 31, a valve seat 32, an elastic sealing member 33, and a bellows for sealing the sliding portion. By closing the valve seat 32 with the lifter_31, the elastic sealing member 33 can close the upstream side. The flow path 81 is between the flow path 81 and the downstream side flow path 82. The on-off valve 3A is operable to elevate the conductance between the upstream side flow path 81 and the downstream side flow path 82 as the rising rainbow (10) degrees of the distance between the valve body 31 and the valve seat 32. The direction of movement of the poppet valve body 31 is also referred to as the axial direction. The amount of rise L is an amount that can be displaced in the axial direction. The actuator 42 drives the poppet valve body 31 to operate the amount of lift L. The actuator 42 has an actuator body 43, a resin-made piston 49 as an insulator, a ceramic piston rod 44 connecting the piston 49 and the poppet valve body 31, a potential energy spring 46 for imparting potential energy to the piston 49, and a support The resin cylinder cover 45 is made of the potential spring 46. The piston 49 forms a cylindrical chamber 45 between the recess 4% formed inside the actuator body 43. A bellofram 49b is a member for sealing the cylindrical chamber 45, and is installed in a gap between the outer peripheral surface of the piston 49 and the inner peripheral surface of the cylindrical chamber 45. An operating air flow path 47 for supplying operating air from an electric air pressure control valve (not shown) is formed in the cylindrical chamber 45. The actuator 42 can control the poppet valve body 31 to an arbitrary position by operating the supply pressure of the actuating air from the electric air pressure control (not shown). The position of the poppet valve body 31 is the load and the load of the actuating air applied to the piston 49.

S 12 201231937 The position of balance with potential capacity is stability. This is because the moving air exerts a load on the piston 49 in the direction of increasing the rising L, and on the other hand, the potential energy spring 46 is biased to the piston 49 in the direction of decreasing the amount of rise L. Fig. 3 is a cross-sectional view showing the structure of the amount of rise sensor 丨〇 of the i-th embodiment. Fig. 4 is a view showing the appearance of the end portion of the lift amount sensor 1 of the first embodiment. Fig. 5 is a view showing the structure of the lift amount sensor 100 of the second embodiment. Fig. 6 is a perspective view showing the structure of the counter electrode of the amount-of-rising sensor 100 of the second embodiment. The up-and-down sensor 1 is a static capacitance type displacement sensor. The ascending amount sensor 100 is a sensor that measures the amount of rise L (refer to Fig. 2). The rise 1 sensor 100 includes a sensor body 60 made of resin, a metal movable electrode 50 having a cylindrical shape, a pair of metal fixed electrodes, 20, and a pair of fixed electrodes 1 and 2, respectively. A resinous sealing portion 73 that penetrates the sensor body 6 to the terminals 71, 72, the sealing terminals 71, 72, and the sensor body 6A. Further, a pair of fixed electrodes 1 〇, 2 〇 are also referred to as outer electrodes. The movable electrode 50 is also referred to as a cylindrical electrode. "T moving electrode 50 is electrically insulated from other parts of the rising amount sensor 100 inside the rising amount sensor. Specifically, the movable electrode 50 is slidably slidably fitted to the resin-made cylindrical cover 45e, and is attached to the resin-made piston 49 and the ceramic-made piston rod 44. In addition, the movable electrode may be electrically insulated from the inside of the lift sensor 100, and an insulator such as a resin insertion member may be mounted between the piston rod 44 or the like to be electrically insulated from other components. The reason why the movable electrode 50 is electrically insulated is described later. As shown in Figs. 3 and 4, the sensor body 6 is mounted on the actuator 42 by four bolts 62 13 201231937. The sensor body 60 is formed with an inner cavity surface 61. On the inner cavity surface 61, a pair of fixed electrodes 10, 20 are spaced apart by a predetermined distance G. The predetermined distance G can be set so as not to be relatively opposed to the excessive parasitic capacitance (static capacitance) of the cut end faces 15, 25. The allowable amount of parasitic capacitance is set in accordance with the comparison with the electrostatic capacitance of the object to be detected. Further, an assembly having a sensor body 6A, a pair of fixed electrodes 10, 20, and a pair of terminals, π is also referred to as a second member. As shown in Fig. 5, an end wall surface 11 is formed inside the fixed electrode 1A, a cylindrical cylindrical wall surface u which connects the end wall surface 11 in the vertical direction, and an outer end surface 13 which is connected to the cylindrical wall surface 12 in the vertical direction. An end wall surface 21 is formed inside the fixed electrode 2, and a cylindrical cylindrical wall surface 22 which is connected to the end wall surface 21 in the vertical direction is connected to the cylindrical wall sheet in the vertical direction: P end face 23. The cylindrical wall surface 12 and the cylindrical wall surface 22 are disposed at opposite positions, and the end wall surfaces 11 and 21 together form a cylindrical internal space Spl. The fixed electrodes 10 and 20 can be mechanically manufactured, for example, as follows. Processing and manufacturing: First, the outer shape is formed by a lathe, and then the end wall faces 11, 21 and the cylindrical circular wall faces 12, 22' are formed by a horizontal boring machine, and finally the cut end faces 15, 25 are formed by cutting. Since the fixed electrodes 1G and 2G can be machined to form an outer shape, high-precision manufacturing can be performed in a general procedure. The circular-shaped internal space Spl can be inserted into the region of the movable electrode 50. The movable electrode 50 is opposed to a pair of fixed electrodes 1〇, 20 electrically insulated state (non-contact state) is inserted. The movable electrode 5G is held in the state in which the E1 fixed electrode 1G is held (the distance of 5 1 is separated. Thereby, the movable electrode 50 is configured to have the pair of fixed electrodes 1) can

S 14 201231937 : The capacitance of the static capacitance C1 on the opposite side of the change in the area of the opposite direction. The movable electrode 50 is inserted into the fixed electrode. In this case, the state of the open electrode can be set to the fixed electrode 10, which has a static capacitance to the opposite surface of the fixed electrode 20 which can vary in the opposing area by the amount of rise L. The static electricity between the movable electrode 5 and the movable electrode 5 is connected in series with a capacitor of the movable electrode 5Q as a conductor and a capacitor C2 formed between the movable electrode 20. Further, the port H) and the counter electrode 20 are electrically connected to the terminal 71 and the terminal, respectively, and a static capacitance of a capacitor which is a capacitor of the capacitor C1 and a capacitor of the electrostatic valley C2 is generated between the pair of terminals 71 and 72. In the internal space Spl, in order to increase the electrostatic capacitance of the detection object to increase the SN ratio, the human has a dielectric fluid. The dielectric current system refers to a fluid having a dielectric property superior to that of conductivity, and for example, an incompressible fluorine-based inert fluid can be used. «Inert fluids have excellent mystery and heat. Since «the viscosity of the inert fluid is small", it is characterized in that the load due to the flow of the relative movement of the outer electrode and the cylindrical electrode can be reduced. Four dielectric fluid passage holes 53 are formed in the movable electrode 5 (only three are shown in the figure). When the dielectric fluid passes through the hole „ inside the movable electrode% inside the inside spi, the through hole for the flow of the dielectric body of the human space Spl is sealed. Specifically, when the amount of rise L is increased, the dielectric fluid passes through the holes 53 through the four dielectric bodies, and is discharged from the internal space Spl. On the other hand, when the amount of increase L is reduced, the dielectric is supplied to the internal space Spl as it passes through the four dielectric current systems (4). As shown in Fig. 1 and Fig. 2, a storage cylinder chamber 55 (see Fig. 2) for storing a dielectric fluid is formed inside the movable electrode 5A. The storage cylinder chamber 55 is configured to be provided with a storage piston 52 so that the capacity inside the storage cylinder chamber μ is variable. An inner hole 44h formed in the inner portion of the piston rod 44 is communicated with the storage cylinder chamber 55. The inner hole 44h is formed with a long hole-shaped communication hole 48h having a long axis in the axial direction, and communicates with the exhaust flow path 48, thereby achieving smooth movement of the storage tongue plug 52. Further, the movable electrode 5A and the storage piston u assembly are also referred to as a first member. Figure 7 of the soil shows the static capacitance ▲ formula conceptually representing the amount of rise sensor. The calculation formula F1 is a definition of static capacitance. The calculation type indicates that the static capacitance generated by the opposing surface between the movable electrode 50 and the fixed electrode 1 is in the y formula. In addition, the calculation formula!? 2 is easy to understand and the description is miniaturized (discrete 彳 ten counts and treat each part as a plane), and the static capacitance ci is divided by the product of the dielectric constant ε and the opposing area s. Calculated by the value of s distance dl. The opposing area S varies depending on the amount of rise L. The partition type F3 is a calculation formula for calculating the static capacitance of the opposing surface between the movable electrode 50 and the fixed electrode 20. The static capacitance C2 is calculated by dividing the product of the dielectric constant £ and the opposite direction by the value of the separation distance d2. The variation of the opposing area s is calculated. The calculation formula F4 is used to calculate the difference between the two capacitors ^, C2 and the capacitor C in series. The core rise amount sensor is used to measure the rise of the composite capacitor C of the terminal. . This is because the composite capacitor ^ is the composite capacitor c of the capacitor of the series capacitor C1 and the capacitor C2. Container The calculation formula F4 is an isoelectric circuit in which two static electricitys gC1 and C2 which are connected by the movable electrode $201231937 and are connected in series by the two fixed electrodes 1 . The equivalent circuit is established as described above on the premise that the movable electrode 5 is electrically insulated from the other components of the lift amount sensor 100. Specifically, it is assumed that an early movable electrode 50 is electrically grounded, and when the potential of the fixed electrode 2 is grounded, the static capacitance C2 between the fixed electrode 20 and the movable electrode 5 is disabled, so that a different circuit is formed. . However, the movable electrode 5〇 does not need to be always electrically insulated, and at least it can be insulated during measurement. The calculation formula F5 is a calculation formula for calculating the composite capacitance c of the capacitor of the capacitor C1 and the capacitor of the capacitor C2. The two separation distances d1 and d2 are calculated by the nominal value (name value) < 5 n and the manufacturing tolerance of the amount of rise sensor 1〇〇. The manufacturing tolerance is mainly the eccentric amount <5 as the assembly error of the movable electrode 50 and the fixed electrode 1〇. The nominal value is the difference between the inner diameter of one of the pair η relative pairs and the outer diameter of the cylindrical wall faces 12, 22 and the outer shape of the movable electrode 50. In other words, when the eccentricity of the assembly error is not present, the value corresponds to twice the distance between the movable electrode 5A and the fixed electrode 1A or twice the distance between the movable electrode 50 and the fixed electrode 20. The calculation formula F6 is expressed by the nominal value 5 η and the eccentric amount 5 indicating the distance dl between the movable electrode 5 〇 and the fixed electrode 10 . The separation distance dl is calculated by the sum of the nominal value η and the eccentricity amount 5. The separation distance d1 indicates that the eccentricity of the movable electrode 50 and the fixed electrode 1〇 is generated in a direction in which the separation distance becomes large. On the other hand, the calculation SF7 calculates the distance d2 between the movable electrode 5A and the fixed electrode 2A by the difference between the nominal value s n and the eccentric amount 5. In the separation distance d2, since the fixed electrode 2 is disposed at a position opposed to the fixed electrode 10 via the movable electrode %, the distance between the movable f pole 5G and the eccentricity of the fixed electrode 2G is reduced in the direction of the distance of 201231937. . The calculation formula F8 is substituted into the calculation formula of the calculation formula F5 of the composite capacitor C by the two separation distances d 1 and d2 calculated by the calculation formula and F7. In the calculation formula F8, it is understood that the eccentric amount <5 is offset, and the composite capacitor C can be calculated from the nominal value $η, the opposing area S, and the dielectric constant ε. That is, it can be seen that the composite capacitor c is not affected by the eccentricity amount 5 in calculation. This effect is as described above, since the rise amount sensor 100 is constructed such that the movable electrode 50 is electrically insulated from other parts of the sensor 100. Fig. 8 is a graph showing measured values of the composite capacitor C in accordance with the amount of rise L of the movable electrode 50 and the pair of fixed electrodes 1 and 20. The theoretical value is shown as a straight line indicating that the relationship between the amount of rise L and the area of the opposite direction S is linear. This is because the opposing area S is the product of the total length of the pair of fixed electrodes 10 and 20 in the circumferential direction and the amount of rise L, and the amount of change is determined. The measured value shows the amount of rise [and the composite capacitor C (static capacitance) is linear. As such, since the amount of rise sensor 100 has linearity between the amount of rise 匕 and the composite capacitor C, it has characteristics suitable as a sensor. Furthermore, the lift sensor 100 shows that there is no limit to the theoretical amount of displacement. This is because the movable electrode 50 and the pair of fixed electrodes 10, 20 are used to maintain the linearity of the sensor, and it is theoretically possible to freely extend in the axial direction. Fig. 9 is a graph showing measurement errors (measured values) due to the eccentricity of the movable electrode 50 and the pair of fixed electrodes 1 〇 and 2 。. This graph is a graph showing the sensitivity analysis of the composite capacitor C with respect to the eccentricity amount 5. This graph is a state in which the eccentricity amount <5 does not exist, the state in which the eccentric amount 5 exists in the direction of the gap G (the slit side), and the eccentric amount (5 exists in the direction of the gap with the distance G).

S 201231937 Three states of the straight direction (no slit side), comparing the measured values. In this experimental example, the nominal value (5η is 200μηι. Thus, the inventors succeeded in confirming that at least the eccentricity of the general manufacturing tolerance is not affected by the composite capacitor C. This experiment has more opposition to the eccentric direction. The significance of the sensitivity analysis of the influence of the composite capacitor C. The sensitivity analysis is used for the necessity of increasing the number of divisions of the outer electrode or determining the optimum value of the split shape. However, according to the experiment, it can be confirmed that The degree of manufacturing tolerance is such that even if the eccentricity is generated in either direction, the composite capacitor C is hardly affected, so it is confirmed that the number of divisions is two. Specifically, for example, when the eccentricity of the slit side is smaller than the eccentricity of the non-cut side In the case of a large influence on the composite capacitor C, in order to reduce the individual difference of the measured values of the vacuum control valve 40, it is also necessary to review the number of increments (distance G) or the adjustment position. However, since it is a general manufacturing tolerance level Even if there is a deviation in either direction, it hardly affects the composite capacitor C, so it is confirmed from the practical point of view that it is not necessary. According to the above analysis and experiment, it is understood that the plane including the direction of the displacement of the poppet valve body 31 as the measurement target is substantially equally divided into two, and is preferably in the form of a pair of counter electrode systems. When the plane is divided by the plane including the direction of the displacement of the measuring object, the capacitance ratio of the capacitor on the side of the fixed electrode 10 and the capacitor on the side of the fixed electrode 20 is not affected by the movement of the measuring object, so that the displacement and the composite capacitor C can be ensured. The linearity of the relationship is caused by the fact that the capacitors on the side of the fixed electrode 10 and the capacitor on the side of the fixed electrode 20 can be formed in series when they are substantially equally divided into two. The composite capacitor C has the maximum value. 19 201231937 This embodiment can achieve the following effects: (1) The amount of rise sensor 10 solves the amount of displacement (maximum amount of rise L) that can be measured in the capacitive sensor The assembly tolerance tolerance (eccentricity δ) of the counter electrode is a problem, and therefore has a linear characteristic as a sensor. (2) The rise amount sensor 100 has a cylindrical electrode The movable electrode 50 and any one of the fixed electrodes 10 and 20 as one of the outer electrodes can be mechanically machined to achieve a precise shape and size. (3) The rise amount sensor 100 is physically non-oriented due to the counter electrode The first embodiment is not limited to the above, and may be implemented as follows. (1) In the above embodiment, the outer electrode is made of a mechanical component, but For example, it may be formed by depositing a metal film on the inner cavity surface 61 formed on the sensor body 60. If this is done, since the opposing area is significantly reduced, the distance G can be reduced, and the opposing area of the measuring object can be increased. The outer electrode may also be such that the sensor body 60 is a heat-resistant resin, and a resin is injected around the metal electrode to be integrally molded by insert molding. Further, the outer electrode may be fabricated by inserting a sandwich structure of the metal pressurizing member on the inner cavity surface 61. As described above, the outer electrode has a broad meaning, and it is only required to have at least one pair of electrodes which are divided in the circumferential direction and opposed to each other. (2) In the above embodiment, the external electrode is divided into two, and may be divided into, for example, three or more. As described above, the outer electrode which can be used in the present invention may be formed into a cylindrical shape and divided into a group of outer electrodes in the circumferential direction. However, as described above, it is divided into two, and the outer electrode is the simplest.

S 20 201231937 Easy structure, which has the advantage of reducing the distance G and increasing the opposing area, and also reducing the stray capacitance by eliminating the wiring. (3) In the above embodiment, the cylindrical electrode (in the embodiment, the movable electrode 50) is formed with an end portion. However, as in the first modification (see Fig. 10), the cylindrical electrode may be disposed in the middle of the movable portion. (for example, between the cylindrical member 51 and the piston rod 44). In the first modification, a resin cylindrical member 51 is attached to the end portion of the movable electrode 50a by a bolt 56. The cylindrical member is a member formed by inserting and molding a resin by injecting a resin around the insertion member 54 in which the female screw is formed. The through hole 51h is for performing a hole for supplying air and exhaust according to the movement of the cylindrical member 51. This structure has the advantage that the dielectric fluid does not need to flow in accordance with the displacement of the measuring object. Thus, the cylindrical electrode does not need to be installed at the end of the measuring object, and may be installed between the actuator 42 and the valve body 41 or inside the actuator 42. Further, it is also possible to adopt a structure in which a cylindrical electrode is sandwiched by a pair of measuring objects. (4) In the above embodiment, a dielectric fluid is used to make the SN relatively high, but the dielectric fluid is not necessarily required. However, when a dielectric fluid is used and a large temperature change of the dielectric fluid is assumed, it is desirable to compensate for the change in dielectric constant due to the temperature change of the dielectric fluid. Specifically, for example, a structure for correcting the temperature of the dielectric fluid or a structure of the second modification described later is preferable. Fig. 11 is a graph showing a state in which the dielectric constant changes in response to the temperature of the dielectric fluid. Line E2 is a line showing the relationship between the temperature of the dielectric fluid and the dielectric constant. The dielectric constant decreases when the temperature of the dielectric fluid rises from 0 to 100 degrees, for example. When the change in the dielectric constant is corrected for the electrostatic capacitance and the rising amount, for example, at a temperature of 0 degrees, an error caused by a change in the dielectric constant corresponding to the variation Ea is generated at 21 201231937. As shown in Fig. 12, the second modification differs from the above embodiment in that a compensation capacitor for compensating for an error due to a change in dielectric constant is provided outside the outer electrode. The capacitor for compensation is a capacitor in which a common dielectric current is used as a dielectric and is fixed to a fixed counter electrode of the pair of fixed counter electrodes 91a and 91b. Different terminals (not shown) are electrically connected to the fixed counter electrodes 91a and 91b, respectively. The pair of fixed counter electrodes 91a and 9lb are disposed in the outer circumferential direction (outer side) of the pair of fixed electrodes 10 and 20, and are disposed between the paired sensor bodies 60a1 and 60a2. Each of the pair of fixed counter electrodes 91a, 91b has an annular shape different in diameter from each other and shares a central axis. The space between the pair of fixed counter electrodes 91a, 91b is communicated with the internal space Sp1 through the communication holes 92, 93. Thereby, the dielectric fluid can fill the space between the internal space Spl and the fixed counter electrodes 91a, 91b. The compensating capacitor is equipped in a state of being electrically separated from the outer electrode or the cylindrical electrode without affecting the electrostatic capacitance between the terminals 71, 72. Since the compensation capacitor can observe the dielectric constant by measuring its electrostatic capacitance, the observed dielectric constant can be used to measure the displacement. Thereby, the compensation capacitor can be mounted without making the size of the measurement object in the displacement direction too large, and the error of the measurement displacement due to the change in the dielectric constant can be compensated. (5) In the tenth embodiment, a fluid different from the fluid to be controlled is used as the dielectric fluid, and the fluid to be controlled may be used as the dielectric fluid in the third modification (see Fig. 13). If this is done, it is not necessary to use a dedicated flow path or storage tank for the dielectric fluid, and the dielectric is simply used.

S 22 201231937 The third modification is an example in which the present invention is applied to the spool valve 4 〇 c of the proportional proportional control valve as the flow 44a of the control dielectric fluid 44a and the movable electrode 5. The bobbin valve 40c has a bobbin 58, which is attached to the bobbin movable electrode 5 by the fastening member 59. This is eliminated by the insulating member insulating member 58 in the bobbin case 4c. Since the movable electrode 5〇1) is made of a metal material as the material of the bobbin 44a, it can also be used as a conductor. In the present specification, the proportional control (four) has a wide selection of items. In addition, the valve opening degree can be measured and the feedback can be made, for example, the meaning of the meaning 'for example, as long as the valve is closed. For example, the spool valve of the third modified example of controlling the mixing ratio is restored to the state of the first, τ, and the green glaze 44a is closest to the side of the 疋 electrode 1G, 2G. In this state, the flow path of the dielectric fluid From the recess formed as a flow path in _4&, it is connected to the opening portion downstream of the flow path through the communication of the opening 57h of the sleeve 57. When the spool 44a is separated from the fixed electrode 1 () and the 2 () side, the flow of the recess 44 oil and the opening 57h are lost. A pair of fixed counter electrodes 91. The end of the training is oriented to this flow. The pair of fixed counter electrodes 91c and 91d are attached to the concave portion 91e formed in the sensor body 60b of the third modification. Between the pair of fixed counter electrodes 91c and 91d, there is a gap in which the dielectric fluid can flow in, and the dielectric fluid is the same as the dielectric fluid flowing between the fixed electrodes 1 and 20 and the movable electrode 5〇b. Similarly, the modification can be utilized as a compensation capacitor. The fixed counter electrodes 91c, 91d have the advantage that the dielectric fluid can flow in without stopping, and the capacitor body can be equipped with the compensation capacitor only when the concave portion 9e' is formed in the sensor body 60b. (6) In the above embodiment, the cylindrical electrode side of the furnace m and the measuring object may be moved to the same side as the outer electrode. In the present invention; ^^--(4)' or 'side electrode as the measuring object becomes the column electrode and (4) the ground moves, at least the pair of outer electrodes can be moved by the ribs (four) . (1) In the above embodiment, the valve body or the bobbin of the vacuum control is described as an example of the measurement target, but it can be applied to, for example, a valve of another type having a valve. In the second embodiment, the second embodiment of the present invention will be specifically described with reference to the drawings, and the second embodiment of the present invention will be specifically described. A spool valve used in a manufacturing line such as a semiconductor device. Fig. 14 is a cross-sectional view showing the sensor installation side of the spool valve of the second embodiment, (a) and (b) showing states in which the bobbins are disposed at different positions. First, the spool valve will be described based on Fig. 14(a). The spool valve 200 includes a valve body portion 201 and a sensor portion 221 for detecting the position of the bobbin. The valve body portion 201 has a valve body 202, and the valve body 2〇2 is The tubular body formed of a metal material such as stainless steel has a hollow portion having a circular cross section perpendicular to the central axis. The valve body 202 is provided with an inflow port 203 and an outflow port 204 communicating with the hollow portion. Hollow part A sleeve 205. The sleeve 205 is also the same as the valve body 202, a cylindrical shape and formed of a metal material such as stainless steel. In the sleeve 205,

S 24 201231937 The circulation annular grooves 2〇6a and 206b and the flow holes 2〇7a and 207b are provided at positions where the inlet port 203 and the outlet port 204 of the valve body 202 are provided, and are passed through the circulation annular grooves 2〇6a and 206b. The flow holes 207a and 207b communicate with the hollow portion of the sleeve 205. The hollow portion of the sleeve 205 forms a cylinder, and the wired shaft 211 is accommodated therein. The axis 211 has its axis aligned with the axis of the cylinder, and the sliding portion 212 is slidable in the state of the inner surface of the cylinder so as to be movable along the axis of the cylinder. Further, as the actuator (not shown) for moving the bobbin 211, a well-known technique such as a pneumatic device of the first embodiment or a device using a solenoid can be suitably used. The bobbin 211 is formed with an annular recessed portion 213 in addition to the sliding portion 212' which is formed to slide on the inner surface of the cylinder. As shown in the figure, the state in which the bobbin 211 is disposed on the side opposite to the sensor portion 221 is the second position. At this position, the sliding portion 212 of the bobbin 211 blocks the flow hole 207b of the sleeve 205. Therefore, the fluid supplied to the inflow port 203 does not flow out from the outflow port 2〇4. On the other hand, the bobbin 211 is moved from the first position, and the state of the moving end disposed on the side of the sensor unit 221 is the second position. Figure 14(b) shows this status. As shown in the figure, the circulation annular groove 2〇6a corresponding to the inflow port 203 and the circulation annular groove 206b corresponding to the outflow port 204 communicate with each other through the flow holes 2〇7a and 2〇7b and the annular recessed portion 213. Therefore, the fluid supplied to the inflow port 2〇3 flows out from the outflow port 204. Returning to Fig. 14(a), the sensor unit 221 is provided on one end side of the valve body portion 2〇1. The sensor unit 221 has a sensor body 222 that extends the valve body 2〇2 to form a cylindrical shape. The open end of the sensor body 222 is blocked by a plug member 223 which is formed in a flat shape. The clogging member 223 is formed of a material having electrical insulation such as oxidized. The hollow portion of the sensor body 222 (the space between the blocking member 223 and the end portion of the sleeve 205) serves as the sensor installation space 224, and is provided in the same manner as the lift amount sensor 100 of the first embodiment. The sensor of the structure. That is, the fixed electrodes 225 and 226 are provided as one of the outer electrodes to the closing member 223. Further, the movable electrode 227 as a cylindrical electrode is attached to the end portion of the bobbin 211 with the insulating member 214 interposed therebetween. In the sensor installation space 224, there is a fluid of a controlled object leaking from between the sleeve 2〇5 and the bobbin 211. This fluid has a function as a dielectric fluid. k Movement of the bobbin 211 As shown in Fig. 14(b), the movable electrode 2 2 7 enters the cylindrical internal space Sp2 formed by the pair of fixed electrodes 225 and 226. At this time, the fluid in the internal space Sp2 flows through the through hole 215 formed in the bobbin 211 to the opposite side. Thereby, the movable electrode 227 enters, and the opposing area of the movable electrode 227 and the fixed electrodes 225 and 226 fluctuates. The position of the bobbin 211 can be detected by grasping the change in electrostatic capacitance caused by the change in area. Returning to Fig. 14(a) again, the pair of fixed electrodes 225 and 226 are provided with electrode terminals 225a and 226a which are respectively conductive portions. The electrode terminals 225a, 226a extend through the blocking member 223 and extend in the moving direction of the bobbin 211 to be exposed outside the sensor installation space 224. A sensor substrate 231 as a circuit board is attached to the protruding end portions of the electrode terminals 225a and 226a. The sensor substrate 231 is formed of a material having electrical insulation such as alumina or synthetic resin. The sensor substrate 231 is disposed outside the sensor installation space 224, and is disposed to be apart from the blocking member 223, and is approximately perpendicularly intersected with the moving direction of the bobbin 211, and the back surface (not formed circuit surface) and the blocking member 223 Opposite.

S 26 201231937 An output circuit or the like for outputting a detection signal of a static capacitance to the outside is formed on the sensor substrate 231. The pair of electrode terminals 225a, 226a are electrically connected to a circuit formed on the sensor substrate 231. A connector 232' is provided on the sensor substrate 23, and a wiring side connector (not shown) provided at an end portion of the electric wiring is connected to the connector 232. By this connection, the signal can be output to the outside through the electric wiring. The sensor substrate 231 and the blocking member 223 are covered by the sensor cover 233. Further, a heat resistor 234 is provided in the clogging member 223, and the detecting portion of the heat resistor 234 is disposed in the internal space Sp2. The thermistor 234 is electrically connected to the circuit formed on the sensor substrate 231, and the temperature signal of the filling fluid (dielectric body) detected by the thermistor 234 can be output to the outside. Based on this detected temperature, temperature compensation of the dielectric constant ε is performed. As a matter of course, the temperature compensation may be such that the compensation capacitor is provided as in the second modification or the third modification of the above-described first embodiment. Further, in the second embodiment, the assembly including the sensor body 222, the pair of fixed electrodes 225 and 226, and the pair of electrode terminals 225a and 226a is also referred to as a second member. Further, the assembly including the movable electrode 227, the insulating member 214, and the bobbin 211 is also referred to as a first member. Here, in the sensor unit 221 having the above configuration, the value of the detected electrostatic capacitance greatly changes due to the external interference of the human body such as the valve body portion 201 or the sensor body 222, and is generated. The difference between the deviations. Moreover, the presence of stray capacitance is also the main cause of the destabilization of the value of the electrostatic capacitance. Therefore, there is a drawback that the detection of the electrostatic capacitance cannot be performed stably. Therefore, in the second embodiment, the cylindrical shielding member 241 is provided in the sensor installation space 224 of the sensor unit 221 . The cylindrical shielding member 241 is formed of a metal material such as 27 201231937 (iron, alloy and alloy) or stainless steel. The cylindrical shielding member 241 is suspended from the blocking member 223 at the end side, and is in a state of being non-contact with any of the sensor body 222 and the fixed electrodes 225, 226. That is, the sensor body 222' is disposed on the outer side of the cylindrical shielding member 241, and a pair of fixed electrodes 225 and 226 are disposed on the inner side. The cylindrical shielding member 241 is electrically connected to the sensor body 222 or the fixed electrodes 225 and 226. The state of insulation. One end of the cylindrical shielding member 241 penetrates the blocking member 223 and protrudes out of the sensor setting space 224. The protruding end portion of the cylindrical shielding member 241 is attached to the sensor substrate 231 by using a fixing member such as a screw or a pin. Therefore, the sensor substrate 231 is supported by the cylindrical shielding member 241. Further, one of the protruding portions of the electrode terminals 225a and 226a is surrounded by the cylindrical shielding member 241, the sensor substrate 231, and the blocking member 223. On the other hand, the end portion of the cylindrical shielding member 241 opposite to the aforementioned sensor substrate 231 is formed to extend to the inside of the sensor installation space 224. More specifically, as shown in Fig. 14(a), the cylindrical shielding member 241 has the second position at which the opposing areas of the electrodes are the smallest, and the movable electrode 227 which can completely cover the state exposed from the internal space Sp2 to the outside can be completely covered. length. Next, on the sensor substrate 231, a film-like metal film 242 is formed by deposition on at least the portion on the back surface opposite to the clogging member 223 and at least the portion to be joined to the cylindrical shielding member 241 and the inner region thereof. The metal film 242 is electrically connected to a grounding circuit formed on the sensor substrate 231, and the grounding circuit is connected to the grounding wiring by the connector 232'. The cylindrical shield member mi is provided in contact with the metal film 242. Therefore, the cylindrical shielding member 241 is also grounded. The metal film 242 is electrically insulated from the electrode terminals 225a, 226a and the portion of the wiring from the thermal resistance 28 201231937 234, respectively. In addition to the above-described configuration, the following results can be obtained in addition to the effect of the amount of rise sensor 〇〇 of the first embodiment. That is, the fixed electrodes 225 and 226 and the movable electrode 227 are covered by the cylindrical shielding member 241. Further, a part of the electrode terminals 225a, 226a extending out of the sensor installation space 224 is also covered by the cylindrical shielding member 241 and the metal film 242. Therefore, when the static capacitance is detected, even if there is a cause of external interference such as the valve body portion 201, the sensor body 222, or the sensor cover 233, the influence of the external disturbance may be suppressed. . Further, the stray capacitance generated between the fixed electrodes 225 and 226 and the movable electrode 227 and the sensor body 222 and between the electrode terminals 225a and 226a is respectively connected to the grounded cylindrical shielding member 241 or the metal film 242. In the meantime, it was cut. Therefore, since the stray capacitance is reduced, the main cause of the instability of the electrostatic capacitance value can be reduced. Thereby, the static capacitance can be stably detected, and the performance that can withstand practical use can be obtained. Further, the content described in another aspect of the first embodiment described above can be applied to the spool valve 2 of the second embodiment. For example, in this embodiment, the fluid to be controlled is used as a dielectric fluid, and this is a third modification of the third embodiment (see Fig. 13). Children. On the contrary, in the modification of the second embodiment, a fluid different from the fluid to be controlled may be used as the dielectric fluid. At this time, in order to prevent the leakage of the fluid to be controlled, the seal body 2〇2 and the sleeve 2〇5 are sealed, and the other forms (1) to (3), (6) and (7) described above can be applied. In addition, in a state in which the sensor substrate 231 and the clogging member 223 are not separated from each other, a configuration in which the clogging member 223 is brought into contact with the clogging member 223 may be employed. Further, the metal film 242 formed on the back surface of the sensor substrate 231 may be omitted. However, in order to stabilize the detection of the electrostatic capacitance, the structure of the embodiment in which the metal film 242 is formed is preferably used. I. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing the structure of the valve fully closed state of the vacuum control valve 40 of the first embodiment. Fig. 2 is a cross-sectional view showing the structure of the valve half-open state of the vacuum control valve 40 of the first embodiment. FIG. 3 is a cross-sectional view showing the structure of the amount of rise sensor 100. Fig. 4 is a view showing the appearance of the end portion of the amount of rise sensor 100. FIG. 5 is a schematic view showing the structure of the lift amount sensor 100. Fig. 6 is a perspective view showing the structure of the counter electrode of the rising amount sensor 100. Fig. 7 is a graph showing the calculation formula of the electrostatic capacitance of the rise amount sensor 100. Fig. 8 is a graph showing the comparison of the electrostatic capacitance of the cylindrical electrode and the outer electrode with the theoretical value. Fig. 9 is a graph showing measurement errors due to eccentricity of the cylindrical electrode and the outer electrode. Fig. 10 is a cross-sectional view showing the structure of the valve fully closed state of the vacuum control valve 40 a of the first modification. Figure 11 is a graph showing the change in dielectric constant in response to the temperature of the dielectric fluid.

S 30 201231937 Fig. 12 is a cross-sectional view showing the structure of the valve fully closed state of the vacuum control valve 40b of the second modification. Fig. 13 is a partial cross-sectional view showing the structure of the dielectric fluid control valve 40c of the third modification. Figs. 14(a) and 14(b) are cross-sectional views showing the sensor installation side of the bobbin valve 100 of the second embodiment. Fig. 15 is a view showing a state in which the opposing area of the counter electrode of the prior art is changed. Fig. 16 is a view showing a state in which the distance between the opposing electrodes is changed in the prior art. Fig. 17 is a graph showing the relationship between the separation distance of the counter electrode and the electrostatic capacitance of the prior art. [Description of main component symbols] 10, 20, 225, 226... fixed electrode 40c, 200··. spool valve 11, 21... end wall surface 41... valve body 12, 22... cylindrical wall surface 42. .. actuators 13, 23... external end face 43... actuator body 15, 25... cut end face 43ah... opening 30... switch valve 44... piston rod 31. Lifting valve body 44a... spool 32... valve seat 44h... internal hole 33... elastic sealing member 44ah, 45h, 91e... recess 37... bellows 45... cylinder chamber 40, 40a.·· Vacuum control valve 45c...Cylinder cover 31 201231937 46.. . Assignment of potential energy spring 47.. Actuating air flow path 48.. Exhaust flow path 48h... communication hole 49. . . piston 49b...pressure regulating valve 50, 50a, 50b, 227 ·. movable electrode 51.. cylindrical member 51h... through hole 52.. storage piston 53.. dielectric fluid through hole 54.. . Insert material 55.. Storage cylinder chamber 56.. bolt 57, 205 · · sleeve 57h... opening portion 58, 214... insulating member 59.. fastening member 60, 60al, 60a2, 60b... sensor body 61.. lumen surface 62.. bolt 71, 72... terminal 73.. seal 80.. flow path 81.. upstream flow Road 82.. The downstream side flow paths 91a-91d... fixed counter electrodes 92, 93... communication holes 100-L lift sensor 201.. valve body portion 202.. valve body 203.. . The outflow ports 206a, 206b... flow through the annular grooves 207a, 207b... the flow holes 211.. the bobbin 212.. the sliding portion 213.. the annular recess 215.. the through hole 221.. Sensor portion 222... sensor body 223.. blocking member 224.. sensor setting space 225a, 226a... electrode terminal 231.. sensor substrate 232.. connector 233.. .Sensor cover

S 32 201231937 234...Thermistor G. · _ 241...Cylinder shielding member 1L/... 242...Metal film Spl C...Composite capacitor δ\ Cl, C2...Static capacitor The predetermined distance rise amount, Sp2·.·internal space, <52...separation distance 33

Claims (1)

201231937 VII. Patent application scope: 1. A static capacitance type displacement sensor which measures the displacement of a measuring object on a straight line, and includes: a first member having a cylindrical cylindrical electrode, the cylinder The cylindrical electrode has a central axis parallel to the straight line; and the second member has a cylindrical outer electrode that is electrically insulated from the cylindrical electrode on the outer side of the cylindrical electrode. The outer electrode has a circumferential direction and is opposite to at least one pair of electrodes, and the cylindrical electrode is electrically insulated from a circuit connected to the outer electrode, and the first member and the second member follow the measurement target. The displacement is relatively moved on the straight line, and the electrostatic capacitance between the at least one pair of outer electrodes changes according to the aforementioned movement. 2. The electrostatic capacitance type displacement sensor according to claim 1, wherein the pair of outer electrodes are equally divided into two and opposite ones in a plane including a direction of displacement of the measuring object. electrode. 3. The capacitive displacement sensor according to claim 1 or 2, wherein the first member has a connection portion for connecting to the measurement object, and the second member has a connection to the at least one pair The outer electrode penetrates at least a pair of conductive portions of the second member toward the outside of the second member. 4. The electrostatic capacitance type displacement sensor according to claim 1, wherein the second member seals the region surrounded by the outer electrode and the cylindrical electrode, and the region is an incompressible dielectric fluid. Fill up. 5. The static capacitance type displacement sensor according to claim 4, wherein the second member further includes a compensation capacitor, wherein the compensation capacitor has a dielectric element disposed in a circumferential direction of the outer electrode In the opposite direction, one pair of mutually different diameters is fixed to the opposite electrode, and the compensation capacitor is connected to a region surrounded by the outer electrode and the cylindrical electrode and a communication hole in a region where the pair of fixed counter electrodes are cooled , the aforementioned dielectric fluid. 6. The capacitive displacement sensor of claim 1, wherein the second member has a sensor body, and the capacitive displacement sensor is provided with a state in which the electrical insulation is present between the outer electrode and the sensor body, and a metal cylinder that covers both the outer electrode and the cylindrical electrode in a range in which the first member and the second member move relative to each other The shielding member is electrically grounded to the cylindrical shielding member. 7. The capacitive displacement sensor according to claim 6, wherein the second member has at least one pair of the outer electrodes, and penetrates the second member toward the outside of the second member. At least one pair of conductive portions, the cylindrical shielding member penetrating the second member toward the outside of the second member, and one of the conductive portions is covered by the tubular shielding member, and the conductive portion and the tubular shielding a circuit board having a back surface facing the electrode side is mounted on a portion of the member that penetrates the outside of the second structure 35 201231937, and a ground connection circuit formed on the circuit board is electrically connected to the back surface of the circuit board. Metal film. 8. A proportional control valve for controlling a flow of a dielectric fluid, comprising: a capacitive displacement sensor as described in claim 4 or 5; and a valve body having a connection In the valve body to be measured of the first member, the valve opening degree is changed in accordance with the displacement of the valve body on the straight line; and the valve body has a flow path for guiding the dielectric fluid to the region. S 36