JP2010515880A - Precision pressure sensor - Google Patents

Abstract

A precision sensor is disclosed that includes a magnet having a magnetic flux density that linearly changes in response to changes in pressure. The precision pressure sensor includes a case engaged with each other including an upper case and a lower case, and a diaphragm that allows an internal space formed between the upper case and the lower case to be divided into two parts. , A magnet with a magnetic flux density that varies linearly on the pole surface according to a straight line parallel to the pole surface, which is fixed so that it can be moved up and down in the lower center of the diaphragm, and senses the displacement of the magnet Therefore, a magnetic sensor installed at a position where the magnetic flux density changes linearly and a spring for supplying an elastic restoring force to the diaphragm are included.

Description

  The present invention relates to a pressure sensor that detects the amount of pressure by sensing the magnetic flux density of a permanent magnet that has moved due to a pressure change, and more specifically, the magnetic flux density that varies linearly according to a straight line parallel to the pole surface of the magnet. It is related with the precision pressure sensor which measures a pressure using a permanent magnet and can detect the amount of pressure and the amount of change of pressure precisely by including the permanent magnet which has.

  In the magnet, magnetic field lines from the north pole to the south pole are generated. Depending on the distance displacement on a horizontal plane parallel to the pole surface of the magnet, the magnetic flux density due to the magnetic field lines does not change linearly.

  Therefore, a sensor that uses a technique for detecting the displacement position of a magnet when the magnet is moved functions as a means for detecting the displacement more precisely. Therefore, it is necessary to employ a program or electronic circuit that corrects nonlinear characteristics. It was. For this reason, in order to correct the distribution of magnetic flux density that is nonlinear with respect to the distance generated in one magnet, many studies have been conducted, so that a plurality of magnets having various types of shapes can be mutually connected. By combining these magnets, a combined magnet structure capable of having a linear magnetic flux density was obtained.

  Various types of non-contact distance measuring devices have been developed in recent years. Such is typically a device that uses a sling resistor potentiometer (sliding resistance potentiometer), but is not reliable enough to ensure satisfaction. In another example, the optical potentiometer has an optical sensor that reads an optical region such as a slit region, but the structure is further complicated.

  There is also an apparatus for reading an area recorded on a magnetic medium with a magnetic sensor. However, the device has a complicated structure and this also has the problem that the absolute position cannot be detected. That is, depending on this structure, only the distance between two specific spots can be measured.

  On the other hand, there are pressure sensors having various shapes determined depending on whether the physical state of the object to be measured is fluid, solid or gas.

  For example, a pressure-strain gauge is typical as a pressure measurement sensor having a solid shape, and a sensor for measuring the pressure of a fluid or gas utilizes a technique for measuring each pressure.

  The method for measuring relative pressure measures the displacement of the diaphragm coupled to the spring due to the relative pressure difference.

  In a normal air pressure (wind pressure) control device used in a boiler, the diaphragm changes when the pressure of the air flowing into the air blower is applied to the diaphragm of the wind pressure sensor (pressure sensor). At this time, the wind pressure sensor operates in an on / off manner, and a micro switch attached to the diaphragm opens / closes an electric circuit to control the air flow rate. Such wind pressure sensors have been used. However, since the wind pressure sensor operates only under a specific pressure, there is a drawback that a wind pressure sensor having a specific standard according to the air blower must be used.

  Therefore, the wind pressure sensor does not perform the function of accurately measuring the amount of flowing air (the amount of air). When the pressure of the flowing air increases / decreases, the wind pressure sensor only functions to reduce / increase the pressure of the flowing air (the amount of air) so that it can be supplied by controlling the rotation speed of the air blower. is there.

  On the other hand, a pressure sensor which is a kind of pressure sensor for detecting a water level is disclosed in Korean Utility Model Registration No. 0119708. As shown in FIG. 1, the pressure sensor includes a diaphragm 140 disposed inside the main body 100. The main body 100 includes upper and lower cases 110 and 130, and the pressure sensor is provided in the hydraulic chamber 131 in response to a change in the diaphragm 140 caused by a pressure change in the hydraulic chamber 131 formed by the diaphragm 140 of the main body 100. Sensing pressure. In the pressure sensor, a light blocking member 200 capable of controlling the amount of light passing therethrough according to a cross-sectional area proportional to the change of the diaphragm 140 is included, and an LED (light emitting diode) 210 and a phototransistor 220 which is a photoelectric cell. However, they are installed so as to be centered on the height passage of the light blocking member 200 while facing each other. Further, in the upper case 110, a spring 160 having a predetermined elastic force is received in a pipe body 150 having an inner peripheral surface, and the inner peripheral surface has a formed thread 151. The spring 160 has a structure in which its elastic force is adjusted according to the height of a cover 170 screwed to a screw thread 151 formed on the inner peripheral surface of the pipe body 150, and is applied from the LED 210. The pressure in the hydraulic chamber 131 is sensed by the output voltage of the phototransistor 220 that changes according to the intensity of the light beam. Therefore, in the above disclosed technique, the water level can be sensed by a change in voltage according to a change in the intensity of the light beam of the optical composite element.

In addition, the pressure sensor disclosed in Korean Utility Model Registration No. 027356 has a space 13 having circulation holes 11a and 12a formed on one side thereof in order to allow inflow / outflow of fluid, The magnetic force from the housing member 10 having the diaphragm 114 that moves up and down in accordance with the pressure of the elastic member and the elastic force of the elastic member included in the space 13, the permanent magnet 20 connected to the diaphragm 14, and the rising permanent magnet 20 is confirmed. The sensing member has a structure including a sensing member 30 disposed adjacent to an operating part in which the permanent magnet 20 moves. In the pressure sensor having such a structure, the sensing member 30 confirms a change in magnetic force from the permanent magnet 20 that moves sensitively in response to a minute change in the pressure of the fluid, so that the fluid flux amount and the fluid Precisely measure the pressure change. However, since the magnetic flux density detected by the sensing member 30 is shown in a non-linear shape and an accurate movement position cannot be measured, such a structure has a problem that only an inaccurate position information can be obtained. Yes.
Korean Utility Model Registration No. 027356

  In order to remedy such problems, when processing the measured magnetic flux density values, a non-linear and complex conversion algorithm is used to convert the magnetic flux density non-linear distribution into a linear distribution. However, in spite of this, there is a problem that it is impossible to overcome the basic error in the algorithm and the error generated in the measuring device.

  In another prior art, when magnet polarities are used, the permanent magnets 20 are arranged so that the four polarities are fixed in correspondence with each other as shown in FIG. There is a known structure in which a sensing member 30 for confirming the magnetic force generated from the permanent magnet 20 is installed on one side of the operating portion where the permanent magnet 20 is raised. In such a technique, due to the non-linear characteristic of the magnetic flux density of the magnet, the information obtained by the sensor that senses the magnetic flux density also has a non-linear characteristic. Despite such problems, such inaccurate position information has been used up to now as pressure information, which is the basic information used to control combustion in boilers. Thus, inefficient operation has been caused by inaccurate control actions.

  Therefore, there is an urgent need for a pressure sensor that can measure the pressure by accurately detecting the moving position of the magnet and responding to a pressure change.

TECHNICAL PROBLEM The present invention has been made in view of the above-described problems, and the present invention is linear along a direction parallel to the pole surface of the magnet at a position spaced a predetermined distance from the pole surface of the magnet. The magnet that generates the magnetic flux density, and being installed at a position spaced from the pole surface of the magnet by a predetermined distance, can detect the linear magnetic flux density when the magnet moves according to the pressure change, and the detected linear magnetic flux A precision pressure sensor is provided that includes a magnetic sensor capable of outputting linear pressure information using density.

TECHNICAL SOLUTION According to an aspect of the present invention, a case including an upper case and a lower case, wherein the upper case and the lower case are engaged with each other, the outer shape of the case, the positive pressure connection formed in the upper case, the lower case In order to allow the internal space formed between the case forming the negative pressure connection formed in the upper case and the lower case to be divided into the upper compartment and the lower compartment, A diaphragm disposed between the upper case and the lower case, and a cross section having a quadrangular shape, which is equivalent to the shape of a sine wave of one cycle, along a diagonal line from one corner of the quadrangular shape By forming a domain wall (boundary wall between the N-pole and the S-pole) having a shape that is formed to a corner that is opposite to the corner, the poles follow a straight line parallel to the pole surface. Magnet magnetized to have a linearly varying magnetic flux density on the surface, fixed to be movable up and down at the lower center of the diaphragm, and magnetic flux to sense the displacement of the magnet Precision including a magnetic sensor installed at a position where the density varies linearly and a spring installed in a lower compartment formed between the diaphragm and the lower case to provide elastic restoring force to the diaphragm A pressure sensor is provided.

  According to another aspect of the present invention, a case including an upper case and a lower case, wherein the upper case and the lower case are assembled to each other and formed into an outer shape, a positive pressure connection portion formed in the upper case, and a lower case. The upper case and the lower part, so that the inner space formed between the case forming the negative pressure connection part and the upper case and the lower case can be divided into the upper compartment and the lower compartment Domain walls (N-pole and S-pole) along the interface connecting the diaphragm disposed between the cases and the center of the side surface having the higher height and the center of the side surface having the lower height Is formed on the pole surface along a straight line obtained by rotating a straight line parallel to the pole surface at a predetermined angle. I have Magnets having a hexahedron with an inclined upper surface fixed so that it can be moved up and down at the lower center of the diaphragm, and the magnetic flux density is linear to sense the displacement of the magnet A precision pressure sensor is provided that includes a magnetic sensor installed at a position that changes to a position and a spring installed in a lower compartment formed between the diaphragm and the lower case to provide an elastic restoring force to the diaphragm. Is done.

Advantageous Effects According to the present invention, the precision pressure sensor senses the pressure by sensing the position of the magnet displaced according to the amount of change in pressure, and the linear magnetic flux density is achieved in proportion to the moving distance. By having the magnet, the precision pressure sensor can accurately measure the pressure. Therefore, since the pressure can be detected accurately, the amount of air in the boiler or the like can be precisely controlled, and the efficiency in the boiler can be improved.

  Hereinafter, representative embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 4 is a perspective view of the shape of a magnet according to an embodiment of the present invention. FIG. 5 is a cross-sectional view taken along line AA illustrating the magnet shown in FIG. 4, FIG. 6 is a perspective view of the shape of the magnet according to another embodiment of the present invention, and FIG. FIG. 8 is a cross-sectional view taken along line BB for explaining the magnet shown in FIG. 6, and FIG. 8 is a graph for explaining the change in magnetic flux density of the magnet according to the present invention.

As shown in FIG. 5, the magnetic flux density of the magnet is inversely proportional to the square of the distance, domain walls, magnetization achieved so as to be positioned diagonally indicated by a dotted line L ₁ which is a boundary line of the N pole and the S pole of the magnet If the magnetic flux density is measured according to a straight line parallel to the pole surface, the graph of magnetic flux density with respect to displacement does not show linearity.

Accordingly, in order to enable a magnetic flux density exhibiting linearity in a predetermined portion of a straight line parallel to the pole surface, the magnet according to the present invention has a domain wall that is a boundary line between the N pole and the S pole in a diagonal direction. a slightly distorted state, as with the solid line L _2, is produced with a sine wave shape of one cycle (circle).

Hereinafter, an embodiment of the experiment measured when the magnetic flux density of the magnet shown in FIGS. 4 and 5 changes linearly according to a straight line parallel to the pole surface will be described. To achieve this, it is assumed that the direction parallel to the pole surface is the x-direction and the direction of the magnetic pole perpendicular to the pole surface is the Y-direction. For convenience of explanation, one side x- direction position in the plane of the magnet and X _0, assumes the x- position in another surface opposite the X ₁₂ to the surface of its one side.

The sensor for measuring the magnetic flux density of the magnet measures the magnetic flux density in the straight line C ₁ D ₁ parallel to the pole surface at a position spaced from the pole surface in the y-direction through the vertical portions X _{0 to} X _12. In the straight lines C ₂ D ₂ , C ₃ D ₃ , C ₄ D _4, etc. formed by measuring and moving the straight line C ₁ D ₁ parallel to the y-direction through the vertical parts X _{0 to} X _{12 of} the magnet The magnetic flux density is also measured.

The result of the experiment is shown in FIG. As shown in FIG. 8, the magnetic flux density has excellent linearity in the portions X _{2 to} X ₁₀ except for the portions that show a little non-linearity in the edges of the magnet portions X _{0 to} X _12. Yes. Thus, if it determines that the position of the part where magnetic flux density shows linearity is a use area | region, after that, it is applicable to the pressure sensor which should be used that way, so that it may demonstrate below.

  As a sensor used for measuring the magnetic flux density in this embodiment, a magnetic sensor used for measuring the magnetic flux density is used among actual pressure sensors. For example, Micronas Co. The Programmable Hall IC of was used.

As shown in FIG. 8, the magnetic flux density shows linearity according to the distance in almost the entire region above the pole surface of the magnet, and the magnetic flux density value for each displacement is almost in a specific portion (ie, X _{2 to} X ₁₀ ). Shows complete linearity.

  Therefore, it can be seen that by changing the magnetized shape of the magnet, a linear magnetic flux density value can be achieved for each displacement in a specific portion spaced a predetermined distance from the pole surface. However, since the distance between the magnetic sensor for measuring the magnetic flux density and the pole surface of the magnet is far, the magnetic flux density is inversely proportional to the square of the distance, so the magnetization shape depends on the position where the magnetization sensor is installed. Must be formed.

  Hereinafter, the magnetization state of the magnet according to another embodiment of the present invention shown in FIGS. 6 and 7 will be described.

As shown in the following figure, the height of both surfaces perpendicular to the bottom surface of the magnet 60B (in the figure, the surface having the lower height is the left surface, the surface having the higher height is the right surface, Similarly, the magnet 60B has a hexahedral shape with the upper surface inclined. For convenience of explanation, the N-pole is formed on the upper side and the S-pole is formed on the lower side. Also, the width of the bottom surface of the magnet 60B and is W, the height of the left side of the S- poles and Sd _1, the height of the right side of the S- poles and Sd _2, the height of the left surface of the N- poles and Nd ₁ , Nd ₂ is the height of the left surface of the N-pole.

The illustrated magnet 60B according to the embodiment is set in a state of Sd ₁ = Nd ₁ , 2Sd ₁ = Sd ₂ and 2Nd ₁ = Nd ₂ , so that the left and right surfaces of the height are 2 (Sd ₁ + Nd ₁ ) = Sd ₂ + Nd ₂ which satisfies the relationship of Nd ₂ . However, in the present invention, the ratio of the height of the left surface to the height of the right surface of the magnet 60B is not limited to 1: 2 as shown in the embodiment. As described below, along a linear path formed at a specific distance from the pole surface of the magnet, some specific height ratio is a ratio that allows the linear magnetic flux density to be generated and Where possible, that particular height ratio is set to achieve magnetization.

Hereinafter, an embodiment of an experiment will be described in which a change in magnetic flux density with respect to each displacement is measured by magnetizing the magnet 69b so that the structure shown in FIGS. 6 and 7 is formed. From the measurement start point A at a specific distance d from the upper end of the right surface of the magnet, the points B ₁ to B ₄ that are different positions of the measurement end point B have different angles extending from the left surface and becoming smaller. Each measuring position is in each straight line that leads.

  The measurement start point A is the position of the end on the side having a high magnetic flux density, and the measurement end position B is the end on the side having a low magnetic flux density.

First, the magnetic flux density of the magnet was measured along a straight line (a line connecting the measurement start point A and the measurement end point b4) parallel to the pole surface from the measurement start point A. Next, in a straight line connecting the measurement end points B ₃ , B ₂ , and B ₁ from the measurement start point A, with the measurement start point A being fixed, while the measurement end point is away from the pole surface in the vertical direction. The magnetic flux density was measured. Here view of the figure, the measurement end point B _1, should be parallel to the bottom surface of the magnet 60B, the straight line is given to connect the measurement start point A to reach the measurement end point B _1. After the measurement start point A was separated from the pole surface in the vertical direction, the measurement operation of the magnetic flux density was repeatedly performed with the position of the measurement end point gradually spaced from the pole surface in the vertical direction as described above.

  By performing the repeated measurement operations in this manner, the position of the magnetic flux density having the most excellent linearity according to the displacement of the magnet 60B can be found, and the magnets can be found in FIGS. When the pressure sensor is used in the pressure sensor described in No. 12, such a position can be set as the installation position of the magnetic sensor that senses the displacement of the magnet.

As shown in the graph of FIG. 8, the result obtained by measuring the magnetic flux density of the magnet 60 </ b> A having a rectangular hexahedron-shaped magnet having a corrected magnetization shape is the result of the corrected magnetization-shaped hexahedral magnet having an inclined upper surface. This is almost the same as the result obtained by measuring the magnetic flux density of the magnet 60B. Further, when the magnet 60 is employed as a sensor for measuring pressure, in the portions X _{0 to} X ₁₂ which are effective portions to be used, linearity is found in the change of the magnetic flux density according to the distance change. it can.

  Accordingly, when such a magnet 60 is employed as a pressure sensor that senses pressure by detecting displacement of the magnet in accordance with a change in pressure, the absolute position of the magnet is accurately determined within a portion where the magnetic flux density exhibits linearity. It is possible to implement a precision sensor that can be sensed.

  9 is a sectional view of a pressure sensor using the magnet 60A shown in FIG. 4 according to the present invention, and FIG. 10 is a sectional view of a pressure sensor using the magnet 60B shown in FIG. 6 according to the present invention. is there.

  When the magnets 60 </ b> A and 60 </ b> B are employed in the pressure sensor shown in FIGS. 9 and 10, the magnets 60 </ b> A and 60 </ b> B are preferably formed integrally so that the magnets are inserted into the diaphragm support 62. In the magnet 60B according to the embodiment shown in FIG. 10, the gradient of the magnet 60B is adjusted, and the magnetic flux density of the magnet 60B changes linearly as described above while the magnet 60B moves up and down according to the movement of the diaphragm 66. The portion to be mounted is positioned so as to be positioned in a direction perpendicular to the diaphragm 66. By achieving this, the magnetic sensor 68 can be installed in a portion where the magnetic flux density changes linearly when the magnet 60B moves up and down, thereby sensing the position of the magnet. Such a gradient is pre-adjusted and formed when the magnet is inserted into the diaphragm support 62, i.e. when it is inserted by the insertion injection method.

  Next, the structure of the pressure sensor according to the present invention will be described with reference to the cross-sectional views of FIGS. 9 and 10, the side view of FIG. 11, and the plan view of FIG.

  In the pressure sensor, the upper case 72 and the lower case 74 are engaged with each other to form an internal space, and the diaphragm 66 is inserted between the upper case 72 and the lower case 74 so that the internal space is divided into two separate rooms. Having an assembly to divide;

  A coupling ridge 64 is formed in the lower portion of the diaphragm 66 and a coupling groove to be engaged with the coupling ridge 64 is formed in the diaphragm support 62 so that the coupling ridge 64 contacts. Therefore, the diaphragm support 62 and the diaphragm 66 are fixedly assembled to each other. As a result, the diaphragm support 62 and the diaphragm 66 are integrally connected to each other in accordance with a change in pressure, so that the magnet 60 moves up and down.

  In a predetermined portion on the upper side of the pole surface of the magnet shown in FIG. 4 or 6, a magnet 60 that generates a linear magnetic flux density along a straight line is assembled to the lower portion of the diaphragm support 62. The magnet 60 has N-pole and S-pole pole surfaces arranged in a direction equal to the moving direction of the diaphragm 66. The magnetic sensor 68 is fixed at a position where a linear magnetic flux density is indicated while being spaced from the pole surface of the magnet 60 in a state where the magnetic sensor is fixed to the PCB 70.

  The PCB 70 outputs position information of the magnet 60 sensed by the magnetic sensor 68 as pressure information.

  The spring 82 disposed at the lower part of the diaphragm support 62 functions to return the displaced position of the diaphragm 66 to its initial position. Diaphragm 66 moves up and down in response to the difference between the level of pressure flowing into positive pressure connection 94 and the level of negative pressure connection 92. When the diaphragm 66 moves, the magnet 60A moves together with the magnet 66, and the magnetic sensor 68 detects the position of the magnet by measuring the magnetic flux density generated in the magnet 60. At this time, the position information of the detected magnet is not the relative position determined by comparing the position of the magnet before the magnet is displaced with the position after the displacement, but the amount of the detected magnetic flux density. The absolute position sensed accordingly.

  According to the present invention described above, when air necessary for combustion of the boiler is supplied, a precise amount of air can be adjusted according to the amount of injected fuel, and the boiler is operated efficiently.

  While a precision pressure sensor according to the present invention has been described, the scope of the invention is not limited thereto, and those skilled in the art will recognize that various modifications can be made without departing from the scope and spirit of the invention disclosed in the appended claims. It will be understood that additions and substitutions are possible.

The above and other objects, features and advantages of the present invention will become more apparent from the foregoing detailed description when considered in conjunction with the accompanying drawings.
It is sectional drawing of the conventional pressure sensor which uses light. It is sectional drawing of the conventional pressure sensor which uses a magnet. It is sectional drawing of the conventional pressure sensor which uses a some magnet. 1 is a perspective view of a magnet according to an embodiment of the present invention. It is sectional drawing along line AA explaining the magnetization state of the magnet shown in FIG. 6 is a perspective view of a magnet according to another embodiment of the present invention. FIG. It is sectional drawing along line BB explaining the magnetization state of the magnet shown in FIG. It is a graph explaining the change of the magnetic flux density of the magnet according to this invention. FIG. 5 is a cross-sectional view of a pressure sensor using the magnet shown in FIG. 4 according to the present invention. FIG. 7 is a cross-sectional view of a pressure sensor using the magnet shown in FIG. 6 according to the present invention. It is a side view of the pressure sensor shown in FIG. 9 and FIG. It is a top view of the pressure sensor shown in FIG. 9 and FIG.

Claims (10)

A case including an upper case and a lower case, wherein the upper case and the lower case are engaged with each other to form an outer shape of the case, a positive pressure connecting portion formed in the upper case, and a lower case. A negative pressure connection, which forms a case;
A diaphragm disposed between the upper case and the lower case so that an internal space formed between the upper case and the lower case can be divided into an upper compartment and a lower compartment. When,
The cross section has a quadrangular shape and is equivalent to the shape of a sine wave of one cycle, and is formed from a corner on one side of the quadrangular shape to a corner facing the corner along a diagonal line. By forming a domain wall having a shape (boundary wall between the N-pole and the S-pole), it is magnetized to have a magnetic flux density that varies linearly on the pole surface according to a straight line parallel to the pole surface. A magnet that is fixed so that it can be moved up and down in the lower center part of the diaphragm;
A magnetic sensor installed at a position where the magnetic flux density linearly changes in order to sense the displacement of the magnet;
A precision pressure sensor comprising: a spring installed in the lower compartment formed between the diaphragm and the lower case to supply an elastic restoring force to the diaphragm. The precision pressure sensor according to claim 1, wherein the magnets are arranged such that a pole direction is perpendicular to a displacement direction of the magnets. The said magnet is being fixed by the diaphragm support body containing the upper plate closely_contact | adhered to the bottom face of the said diaphragm, and the perpendicular plate formed perpendicularly | vertically at the position adjacent to the center part of the said upper plate in the lower direction. The precision pressure sensor described in 1. The coupling groove formed on the upper plate of the diaphragm support and the coupling ridge formed on the lower surface of the diaphragm are closely assembled to each other so that the diaphragm and the diaphragm support are connected to each other. The precision pressure sensor of claim 3, assembled together. The precision pressure sensor according to claim 1, wherein the magnetic sensor is installed at a position spaced in the direction of the pole surface of the magnet in order to detect a magnetic flux density according to the displacement. A case including an upper case and a lower case, wherein the upper case and the lower case are assembled to each other, an outer shape, a positive pressure connection portion formed in the upper case, and a negative pressure connection formed in the lower case Part, forming a case,
A diaphragm disposed between the upper case and the lower case so that an internal space formed between the upper case and the lower case can be divided into an upper compartment and a lower compartment. When,
A domain wall (boundary wall between the N-pole and the S-pole) is formed along the boundary surface connecting between the center of the side surface having the higher height and the center of the side surface having the lower height. Thus, a magnet magnetized to have a linearly varying magnetic flux density on the pole surface along a straight line obtained by rotating a straight line parallel to the pole surface at a predetermined angle. A magnet which is a hexahedron having an inclined upper surface fixed so as to be moved up and down at a lower central portion of the diaphragm;
A magnetic sensor installed at a position where the magnetic flux density linearly changes in order to sense the displacement of the magnet;
A precision pressure sensor comprising: a spring installed in the lower compartment formed between the diaphragm and the lower case to supply an elastic restoring force to the diaphragm. The precision pressure sensor according to claim 6, wherein the magnets are arranged such that a pole direction is perpendicular to a displacement direction of the magnets. 8. The diaphragm is fixed by a diaphragm support including an upper plate closely contacting a bottom surface of the diaphragm and a vertical plate formed perpendicularly to a position adjacent to a center portion of the upper plate in a lower direction. The precision pressure sensor described in 1. The coupling groove formed on the upper plate of the diaphragm support and the coupling ridge formed on the lower surface of the diaphragm are closely assembled to each other so that the diaphragm and the diaphragm support are connected to each other. The precision pressure sensor of claim 8, assembled together. The precision pressure according to claim 6, wherein the magnetic sensor is installed at a position where a linear magnetic flux density is shown in an upper direction of the pole surface of the magnet, so that the magnetic flux density is detected according to the vertical displacement of the magnet. Sensor.

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