KR20100004743A - Accurate pressure sensor - Google Patents

Abstract

PURPOSE: A minute pressure sensor is provided to sense exact distance variation by using a magnet emitting linear magnetic flux density corresponding to the distance variation. CONSTITUTION: A minute pressure sensor comprises a square magnet(60). Straight lines are apart from each other on the polar surface of the magnet and are parallel to the polar surface of the magnet. The pressure sensor measures the displacement of the magnet having linear magnetic flux density along the straight line and detects the pressure.

Description

Accurate Pressure Sensor

The present invention relates to a pressure sensor that can accurately measure the pressure, and more particularly, the magnet is configured in a rectangular shape, or the magnet is a right side than the left side, the upper surface is formed in a rectangular shape formed in an oblique line N pole Alternatively, a precise distance (position) change (displacement) can be obtained by using a magnet that emits linear magnetic flux density in response to a distance change along a straight line formed from an arbitrary point on the pole surface by being spaced a certain distance from the pole surface of the S pole. The present invention relates to a pressure sensor that senses and derives a precise pressure difference according to a distance change.

Before describing the pressure sensor, the general characteristics of the magnet used herein will be described.

Magnets are magnetic objects that attract iron powder, and industrially strong magnets are called permanent magnets, which are commonly referred to simply as magnets.

The piece of iron placed next to the magnet is attracted to the magnet. The space affected by magnetic force is called a magnetic field. In other words, magnets create a magnetic field. The method used to see the shape of the magnetic field is iron powder pattern. If you place thick white paper on the magnet and spread iron powder evenly on top of it, the magnetic line pattern appears. When a small needle is placed on it, it indicates the direction along the line of magnetic force, and the line of magnetic force exits the N pole of the magnet and enters the S pole.

The force between the two poles follows Coulomb's law, which is inversely proportional to the square of the distance and proportional to the strength of the magnetic pole. The product of the magnetic pole strength and the distance between the two poles is defined as the magnetic moment. In the magnetic pole, the N pole and the S pole of the same intensity are necessarily one pair, so the magnetic moment is considered to be an essential physical quantity rather than the strength of the magnetic pole. The magnetic moment is represented by a vector from the S pole to the N pole in consideration of its direction. Calculating the force between two magnetic moments is inversely proportional to the square of the distance. This is because the attraction between the two magnets is strong when approaching and rapidly weakens when dropped.

Magnetization proceeds by changing the shape, arrangement, and direction of the magnetic zone. They have a structure that is hard to change, and once magnetized, even if the magnetic field is zero, the magnetic moment remains. Permanent magnets have a large residual magnetization.

Magnetic flux is the amount by which the magnetic flux density or magnetic induction is integrated with respect to the cross-sectional area perpendicular to the direction, and is also called magnetic force flux. The unit is Maxwell (symbol Mx) in the CGS unit system and Weber (symbol ㏝) in the MKS unit system or SI unit system. If the magnetic flux passing through the coil changes over time, a voltage proportional to the rate of change occurs between the ends of the coil (Faraday's law of electromagnetic induction). The direction of this voltage is the direction in which the magnetic field generated by the current interferes with the change in the magnetic flux. This is called Lenz's law. Magnetic flux is created by the current flowing through a permanent magnet or coil.

There are many different types of detection sensors depending on how the magnetic field is detected, but perhaps the most widely known sensor is a Hall sensor. In the operation of the hall sensor, when a current flows through an electrode of a semiconductor (hall element), when a magnetic field is applied in the vertical direction, an electric potential is generated perpendicular to the direction of the current and the magnetic field direction.

In general, the simplest distance measuring device uses a sensor that detects permanent magnets and magnetic flux, and measures the distance by the potential difference generated by the magnetic sensor by measuring the change in magnetic flux density as the distance from the permanent magnet increases and decreases. will be.

However, since the magnetic flux density generated in the permanent magnet is not formed linearly with distance, it must be equipped with a program or electronic circuit that compensates for nonlinearity in order to be used as a magnetic sensor to measure distance effectively. Could do it. In addition, in order to compensate for the distribution of nonlinear magnetic flux density according to the distance generated from one magnet, infinite research has been conducted to obtain a structure having linear magnetic flux density by combining various types of magnets and a plurality of magnets.

Recently, various types of non-contact distance measuring devices have been gradually developed in order to detect the absolute position of the body and to measure the linear and angular displacement in the linear range or the range of the angle.

There are various aspects of the non-contact measurement position detection itself. Devices using sliding resistor potentiometers are the most representative but not sure enough. Optical positioners have an optical sensor that reads an optical range, such as a slit range, but the structure is more complicated. Moreover, although the range used for the magnetic medium has a magnetic range that is read by the magnetic sensor, the structure is also complicated and the absolute position cannot be detected.

That is, only the distance between any two points can be measured. The present invention can detect the absolute position of the body to be detected, and it is inexpensive without using a program or an electronic circuit to compensate for nonlinearity if a magnet having a very simple structure, a long measuring area, and a linear magnetic flux density having high reliability is used. Sensors can be used to measure distances more accurately.

The present invention is a pipe connecting the positive and negative pressure and the diaphragm and the diaphragm support attached to one side of the diaphragm and the diaphragm that is attached to one side of the diaphragm and the linear magnetic flux to emit a linear magnetic flux attached to the diaphragm support It consists of a spring and a top and bottom case surrounding these components.

Pressure refers to the force that two objects exert on each other perpendicularly to the contact surface when two objects are in contact with each other and are pressed against each other. In this case, it is also called pressure. In this case, it considers an arbitrary surface in an object and thinks that it is the force (stress) which both parts apply to this surface mutually. When this force is not perpendicular to the plane, it is divided into components perpendicular to the plane and components parallel to the plane, and only the pressing force of the vertical component is called pressure (the pulling force is tension).

Since the pressure acts evenly on the plane with the width, the strength of the pressure on each point depends on the area of the force even though the magnitude of the total force is called the force or the force. If the force of magnitude P is uniformly applied to an object of width S, the pressure strength is defined as P / S. When an object is placed on a desk, the pressure intensity generally depends on the position, so the strength of the pressure of the point can be obtained by the amount of micro force acting on the micro area including the point for each point. The strength of pressure is sometimes referred to simply as pressure.

There are various types of pressure sensors in the sensor used to measure such pressure, and the type may vary depending on the object to be measured.

* The pressure can be classified into fluid, solid, and gas according to the object to be measured. The stress strain gauge is typically used to measure the pressure of a solid, and the relative pressure must be measured to measure the pressure of the fluid or gas. Therefore, the relative comparative pressure is measured using a diaphragm.

The method for measuring the relative pressure is to measure the state pressure by measuring the displacement of the diaphragm combined with the spring due to the relative pressure difference.

The present disclosure relates to a sensor for measuring relative pressure using a diaphragm and a spring, and the sensor may be widely used for measuring a pressure of a fluid or a gas.

As one embodiment of the present application can be applied to a boiler having a pressure sensor capable of measuring the flow rate of the air flowing in, conventional air pressure (wind pressure) detection device for the boiler, the pressure of the air flowing into the blower pressure sensor ( On / off wind pressure sensor (pressure sensor) is used to control the amount of air flowing in by passing to the diaphragm of the pressure sensor to allow the micro switch attached to the diaphragm to open and close the electric circuit. However, the wind pressure sensor (pressure sensor) has a disadvantage in that a specific wind pressure sensor must be used according to the blower because it uses a fixed working pressure.

In addition, the wind pressure sensor does not accurately measure the flow rate (air amount) of the incoming air, but increases or decreases the inlet air pressure (air amount) through the rotation speed control of the blower according to the increase or decrease of the incoming air pressure. It only played a role.

 There are various types of pressure sensors capable of detecting the pressure of such a fluid, and among them, pressure sensors capable of detecting a flow rate using a flow pressure (differential pressure) of the conventional fluid have been presented.

As a type of pressure sensor for detecting a conventional water level, the pressure sensor shown in Utility Model Registration No. 0119708 pressure sensor, as shown in Figure 1, the inside of the main body 100 consisting of upper, lower covers (110, 130) A pressure having a diaphragm 140 and detecting the pressure in the pressure receiving chamber 131 by the change of the diaphragm 140 according to the pressure change of the pressure receiving chamber 131 formed by the main body 100 and the diaphragm 140. In the sensor, there is provided a light blocking member 200 to control the amount of light passing by the cross-sectional area in proportion to the change of the diaphragm 140, the light emitting element is a light emitting element around the lifting path of the light blocking member 200 A diode 210 and a phototransistor 220 as a light receiving element are installed to face each other, and the upper cover 110 receives a spring 160 having a constant elasticity in the tubular body 150 having a thread 151 formed therein. , The spring (160) ) Is configured to adjust the elastic force according to the rising and falling of the screw thread 151 formed on the inner circumference of the tube 150 and the cover 170 to be assembled by the screw, the photo is changed in accordance with the amount of light applied from the light emitting diode 210 By configuring the pressure in the pressure receiving chamber 131 through the output voltage of the transistor 220, there has been proposed a pressure sensor that can detect the water level through the voltage change according to the light quantity change of the optical coupling element.

Another type of pressure sensor is a pressure sensor shown in Utility Model Registration No. 0273056, and as shown in FIG. 2, flow ports 11a and 12a are formed at one side to have a space 13 through which fluid flows in and out. The space 13 includes a housing member 10 having a diaphragm 14 that vertically flows according to the pressure of the fluid and the elasticity of the elastic member; A permanent magnet 20 interlocked with the diaphragm 14; The permanent magnet 20 is provided adjacent to the operating section to move, characterized in that the configuration consisting of a sensing member 30 for checking the magnetic force from the rising and falling permanent magnet 20, fine to the minute pressure change of the fluid The sensing member 30 checks the change in the magnetic force from the permanent magnet 20 to be moved so that the change in the flow rate and pressure of the fluid can be measured more accurately. However, the permanent magnet and the sensing member 30 used in such a configuration is inevitably obtained inaccurate position information for measuring the exact position due to the non-linear characteristics of the magnet.

In more detailed description of FIG. 2, since the inside is sealed to measure the displacement of the diaphragm 14 moving according to the pressure difference, the displacement is used in a non-contact manner to obtain accurate control information. It is a kind of non-contact proximity sensor that uses simple method to measure the density of magnets. It shows the distribution of non-linear magnetic flux density, which shows that the density decreases in inverse proportion to the square of the distance according to the distance, which is the characteristic of ordinary magnets. Even if the conversion is performed linearly using this expensive and complicated conversion algorithm, there is a structural disadvantage that cannot accurately overcome the fundamental algorithm error and the measurement device error.

Another attempt is not to use only one polarity, but a configuration having four polarities corresponding to each other as shown in FIG. 3, so that the sensing member checks the magnetic force from the permanent magnet 20 when the four polarities are formed. 30 is provided to one side of the operation section in which the permanent magnet 20 is elevated, but the information of the sensor for detecting the density of the magnetic flux due to the non-linear characteristics of the magnet also has a non-linear characteristic to detect the actual position In addition, distorted position information due to nonlinear characteristics is inevitably obtained.

Such distorted positional information causes distortion of pressure information, which is the basic information for controlling the equipment, and inaccurate boiler or equipment control based on such information, resulting in inefficient operation of the equipment or equipment. Will be.

Therefore, there is an urgent need for a pressure sensor that can accurately measure the pressure difference by measuring more precise displacement.

The present invention for solving the above problems relates to a pressure sensor that can accurately measure the pressure, and more particularly, the magnet is formed in a square shape, or the magnet is a right side higher than the left side, the upper side is formed with an oblique line Accurate distance using a magnet that has a rectangular shape and emits a linear magnetic flux density in response to a distance change along a straight line formed from an arbitrary point on the pole surface, spaced a certain distance from the pole surface of the N pole or the S pole ( It is an object of the present invention to provide a pressure sensor that detects a change in position) and derives a precise pressure difference according to a distance change.

The configuration of the present invention for achieving the above object is in detail,

In the pressure sensor,

The magnet consists of a square shape,

N and S poles are magnetized in a sin waveform along the diagonal line diagonally from the corners of the rectangle, and are separated by a certain distance from the pole surface of the magnet and are parallel to the pole surface of the magnet (CD) (CD: C1-D1, C2 -D2, C3-D3, C4-D4) characterized by detecting the pressure by measuring the displacement with a magnet having a linear magnetic flux density,

At the end point of the high density of magnetized magnets of the N pole or the S pole, which is a component of the magnet, a point vertically spaced apart from the surface of the pole becomes a starting point C measured by the magnetic sensor,

At the starting point (C), a point spaced a certain distance from the pole surface perpendicularly to the starting point (C) becomes the end point (D) measured by the magnetic sensor,

From the start point (C) to the end point (D) along a straight line parallel to the pole surface (line with start and end points: CD) (CD: C1-D1, C2-D2, C3-D3, C4-D4) A magnet having a linear magnetic flux density in a 2-10 section which is an effective section in a measurement section 0-12 in response to a moving distance change, characterized in that the pressure is detected by measuring the displacement of the magnet,

The magnetic flux density of the N pole or the S pole, which is a component of the magnet, increases the distance d from the start point C to the end point D, so that the straight lines C1-D1, C2-D2, C3-D3, and C4-D4 respectively. Along the straight line C2-D2 to find a straight line (eg C2-D2) indicating the linearity of the magnetic flux density measured by the magnetic sensor relative to the moving distance of the magnetic sensor. It is characterized in that the pressure is detected by measuring the density by measuring the density according to the change in distance,

The pressure sensor has a diaphragm support 62 coupled to the diaphragm 66,

A magnet disposed on the diaphragm support 62 such that a straight line connecting the start point C2 and the end point D2 for measuring the magnetic flux density of the magnet with a magnetic sensor is perpendicular to the operation direction of the diaphragm 66;

A magnetic sensor 68 which senses the magnetic flux density of the magnet, coincides with a straight line connecting the start point C2 and the end point D2 to measure the magnetic flux density of the magnet with a magnetic sensor, and is disposed perpendicular to the lower surface of the lower plate case; ,

And a spring 82 installed between the diaphragm support 62 and the lower surface of the lower plate case.

And a diaphragm 66 for dividing the inner space formed by the lower plate case and the upper plate case into two compartments.

A positive pressure connecting portion communicating with the upper compartment and a negative pressure connecting portion communicating with the lower compartment of the two compartments;

It relates to a precise pressure sensor, characterized in that for detecting the pressure by measuring the relative displacement of the magnet coupled to the diaphragm support 62 in accordance with the vertical movement of the diaphragm 66.

In addition, in the pressure sensor using a magnet to measure the relative distance change of the diaphragm 66 moving up and down in accordance with the pressure change, with a magnetic sensor,

The magnet has a higher right side than the left side, and the upper side has a rectangular shape formed by diagonal lines.

At the right end point of the pole surface, which is the high density magnetized magnet of the N pole or the S pole, a point vertically spaced apart from the pole surface by the magnetic sensor becomes a starting point A,

At the left end point of the pole surface where the magnetized magnet density is low, the point vertically spaced apart from the start point from the pole surface becomes the end point (B: B1, B2, B3, B4) measured by the magnetic sensor.

Each distance for measuring the magnetic flux density with a magnetic sensor along a straight line connecting the start point (A) and the end point (B: B1, B2, B3, B4) is used as a measurement section, and is nonlinear in the measurement section 0-12 section. It is characterized in that the pressure is detected by measuring the relative displacement with a magnet having a linear magnetic flux density in the 2-10 section, which is an effective section excluding the edge section that can show sex,

N and S poles, which are components of the magnet, are composed of magnets magnetized to a metal having a ratio of 1 to 1.5 to 4 in the width of the left side to the right side, and the starting point A and the ending point B are B1, B2, The distances for measuring the magnetic flux density with a magnetic sensor along the straight line connecting B3 and B4) are measured intervals, and 2-10, which is an effective interval excluding edges that can show nonlinearity in the measured intervals 0-12. It characterized in that the pressure is detected by measuring the relative displacement with a magnet having a linear magnetic flux density in the section,

The magnetic flux density of the magnet is a starting point (A) measured by a magnetic sensor at a point where the magnet density of the magnetized high density of the N pole or the S pole is high, at a predetermined distance from the pole surface.

At the end point of the part where the magnetized magnet density is low, the point spaced a certain distance from the pole surface becomes the end point measured by the magnetic sensor (B: B1, B2, B3, B4),

Whether the magnetic flux density of the magnet is linear from the starting point A to the end point B4 along a straight line parallel to the pole surface (a line having a starting point and an end point: A-B4) is linear in an interval of 2-10, which is an effective section. Measured with a magnetic sensor,

The magnetic flux density of the magnet is gradually increased from the end point vertically spaced from the pole surface so that the absolute height is increased to the same height as the starting point A to the point where the height is increased (B3, B2, B1). Measure the linearity in the 2-10 section which is the effective section, and find the end point (e.g. B3) indicating the linearity in the 2-10 section which has the magnetic flux density.

Characterized in that a magnetic sensor for measuring the magnetic flux density on a straight line (A-B3) connecting the starting point (A) and the found end point (B3),

The pressure sensor has a diaphragm support 62 coupled to the diaphragm 66,

A magnet in which the diaphragm support 62 has a straight line connecting the start point A and the end point B3 for measuring the magnetic flux density of the magnet with a magnetic sensor, and is perpendicular to the operation direction of the diaphragm 66;

A magnetic sensor 68 which senses the position of the magnet, coincides with a straight line connecting the start point A and the end point B3 for measuring the magnetic flux density of the magnet with a magnetic sensor, and is disposed perpendicular to the lower surface of the lower plate case;

And a spring 82 installed between the diaphragm support 62 and the lower surface of the lower plate case.

And a diaphragm 66 for dividing the inner space formed by the lower plate case and the upper plate case into two compartments.

A positive pressure connecting portion communicating with the upper compartment and a negative pressure connecting portion communicating with the lower compartment of the two compartments;

It relates to a precise pressure sensor, characterized in that for detecting the pressure by measuring the displacement of the magnet coupled to the diaphragm support 62 in accordance with the vertical movement of the diaphragm 66.

In addition, the pressure sensor and the diaphragm support 62 coupled to the diaphragm 66,

A magnet in which the diaphragm support 62 has a straight line connecting the start point A and the end point B3 for measuring the magnetic flux density of the magnet with a magnetic sensor, and is perpendicular to the operation direction of the diaphragm 66;

The magnetic force is sensed and coincides with a straight line (A-B3) connecting the start point (A) and the end point (B3) for measuring the magnetic flux density of the magnet with a magnetic sensor, and is disposed perpendicular to the lower surface of the lower plate case. Sensor 68,

And a spring 82 installed between the diaphragm support 62 and the lower surface of the lower plate case.

And a diaphragm 66 for dividing the inner space formed by the lower plate case and the upper plate case into two compartments.

A positive pressure connecting portion communicating with the upper compartment and a negative pressure connecting portion communicating with the lower compartment of the two compartments;

It relates to a precise pressure sensor, characterized in that for detecting the pressure by measuring the displacement of the magnet coupled to the diaphragm support 62 in accordance with the vertical movement of the diaphragm 66.

The effect of the present application is that inaccurate control is inevitable due to the inaccurate position information of the position sensors using a conventional magnet in the precision control device that detects the pressure and performs precise control. The internal pressure sensor allows for more precise control.

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

1 is a cross-sectional view of a pressure sensor using a light of the prior art, FIG. 2 is a cross-sectional view of a pressure sensor using a magnet of the prior art, FIG. 3 is a cross-sectional view of a pressure sensor using a plurality of magnets of the prior art, and FIG. 5 is a view showing a magnet shape and a magnetized shape, FIG. 5 shows a magnet shape and a magnetized shape according to another embodiment of the present invention, and FIG. 6 is a graph showing magnetic flux density changes of triangles and rectangles according to the present invention. 7 is a cross-sectional view of a precise pressure sensor using a magnet releasing a linear magnetic flux density according to the present invention, Figure 8 is a side view of a precise pressure sensor using a magnet releasing a linear magnetic flux density according to the present invention, 9 is a plan view of a precise pressure sensor using a magnet that emits a linear magnetic flux density according to the present invention.

1 to 3 have already been described in the prior art, Figure 4 shows a view showing the shape and magnetized shape of the magnet according to the present invention,

When the magnet shape is magnetized in the diagonal direction indicated by the dotted line as shown in FIG. 4, the magnetic flux density of the N pole according to the displacement is inversely proportional to the square of the distance, so that the magnetic flux distribution is measured in a diagonal direction instead of a constant direction. When the magnetic flux density was measured 1mm away from the N pole, the magnetic flux density graph was deformed to show the linearity in a certain region because the change of magnetic flux density due to displacement does not appear straight, as shown in FIG. 4A. .

In order to change the magnetic flux density according to the distance to show the straightness in a certain section, as shown in FIG. 4, the shape of the magnet was deformed to be slightly distorted in the diagonal direction.

In Figure 4, the displacement of the magnetic sensor is formed in a straight line along each straight line C1-D1, C2-D2, C3-D3, C4-D4 connecting the CD, the magnetic sensor is a straight line C1-D1, Magnetic flux density is measured by moving along C2-D2, C3-D3, and C4-D4, and each straight line is called a measuring section, and the measuring section is divided into 12 equal parts and scaled from 0 to 12. Will be fed.

Measurements are taken over the measurement interval 0-12, where a certain distance d is moved away from the pole surface and perpendicular to the pole axis, in a direction parallel to the pole surface. The section 2-10 can be used as a more accurate position sensor (effective section), except for a portion of the measurement section 0-12 that shows a slight non-linear edge.

The magnetic flux density of the N pole or the S pole, which is a component of the magnet, is gradually increased by the distance d from the start point C to the end point D, respectively, and the straight lines C1-D1, C2-D2, C3-D3, and C4-D4, respectively. ) And find a straight line (e.g. C2-D2) where the magnetic flux density measured by the magnetic sensor is linear with the measured magnetic flux density relative to the moving distance of each straight line, and the magnetic sensor measures the magnetic flux density along the straight line C2-D2. By measuring the displacement of the magnet according to the distance change, the pressure of the pressure sensor is detected.

In order to measure the change of magnetic flux density according to the actual distance, the magnetic flux density change by displacement was measured by using the Programmable Hall IC. The programmable Hall IC used is a Micronas component with an error rate of ± .1%. The experimental results are shown in the graph of FIG.

Figure 6 is a graph showing the change in magnetic flux density according to the present invention, the magnetic flux density over a whole range (0-12) (e.g., C2-D2) (measurement section) has a certain linearity depending on the distance, a certain area In the (2 ~ 8) section (effective section), the magnetic flux density by displacement is almost perfect. Therefore, it can be seen that the magnetic flux density of each displacement can be made linear in a certain region by changing the magnetization shape of the magnet. However, as the distance to measure the magnetic flux density increases, it is inversely proportional to the square of the distance, so it is necessary to design the magnetized shape according to the measured distance.

This paper suggests that the north pole and the south pole are magnetized in a sin waveform along the diagonal line from the edge of the rectangle, and find the locus (C2-D2) where the magnetic flux density values linearly appear in a certain area. The pressure sensor is assembled so that the magnetic sensor is positioned so that the magnetic sensor measures the displacement of the magnet coupled to the diaphragm according to the displacement of the diaphragm.

Figure 5 shows a magnetized shape of a magnet according to another embodiment of the present invention, the width W of the lower surface of the magnet can be adjusted as needed, the left side of the S pole of the magnet is Sd1 and the right side The height of is shown to be Sd2, and the left side of the N pole of the magnet is Nd1 and the height of the right side is Nd2 and is arranged above the S pole. Therefore, in the configuration in which the S pole and the N pole are arranged, the left side is Sd1 + Nd1, and the right side is Sd2 + Nd2, and the right side is formed in a square having a height higher than the right side.

When the shape of the magnet is indicated by numbers, it shows that the left side of the S pole of the magnet is 1 and the height of the right side is 2, and the left side of the N pole of the magnet is 1, and the height of the right side is 2, It is a configuration arranged at the top. Therefore, the configuration in which the S pole and the N pole are arranged is a quadrangular shape in which the left side is 2 and the right side is 4, and the right side is twice as high as the right side.

Preferably, the N pole and the S pole are magnetized in an area having a ratio of 1: 1.5 to 4 in the width of the left side to the right side, so that the magnetic flux density measured by the magnetic sensor maintains linearity.

The magnets were magnetized to the structure as shown in FIG. 5 to measure the change in magnetic flux density for each displacement. The measurement position was slightly different from the measurement position along a straight line connecting points B1 to B4, which are points of different angles of the left side B point from the point A at which the arbitrary distance d was separated from the upper end of the right side of the magnet.

In detail, the magnetic flux density of the magnet is a starting point A measured by the magnetic sensor at a point vertically spaced apart from the pole surface of the magnetized portion of the N-pole or the S-pole, which has a high magnet density. At the end point of the low magnetic density, the end point (B: B1, B2, B3, B4) measured by the magnetic sensor at points spaced a certain distance from the pole surface perpendicularly to the start point,

The magnetic flux density is measured by a magnetic sensor along a straight line parallel to the pole surface from the starting point A, and the respective end points B3, B2 and B1 from the starting point A. It is to sequentially measure whether the magnetic flux density of the magnet is linear.

In addition, the distance is vertically spaced apart from the pole surface, and gradually increases the distance from the end point so that the absolute height is the same height (B1) as the start point (A) by repeating the height of the end point (B4), Incrementally increase to B3, B2, B1, and measure the magnetic flux density of the magnet along the straight line of A-B4, A-B3, A-B2, and A-B1. (Any one of B1, B2, B3, B4).

Therefore, the graph is shown in Fig. 6 which will be described below in the position where the most straightness of the measured values is the most straight, using the most straightest position except the edge as the start point (A) and the end point (for example, B3). It is applied to the pressure sensor so that the position of the magnetic sensor passes through the straight line (A-B3). At this time, the measured value measured at the edge portion of the magnet is to adopt the section of 2-10 except for the edge portion of the above-described magnet section (measurement section) of the magnet described above as a more precise position sensor. Excluding the edge section is difficult to magnetize to have the straightness to the edge when the magnetization, this technique is a research and development in the future.

The different measurement positions as shown in Figure 5 is to find a position excellent in the linearity of the magnetic flux density measured by the magnetic sensor. Also, the larger the density of the magnetic flux, the smaller the trajectory affecting the magnetic flux, and the smaller the density of the magnetic flux, the larger the trajectory affecting the magnetic flux. The position of A spaced apart from the initially measured pole surface can be changed. The ratio of the height of the left side and the right side varies according to the size and magnetization strength of the magnet, thereby changing the shape of the magnet.

However, since it is possible to repeatedly fix the shape of the magnet and magnetize the magnet, it is more convenient to find and use a linear position of magnetic flux density in the magnetized magnet.

6 is a graph showing changes in magnetic flux density of triangles and rectangles according to the present invention, in which the magnets of rectangular magnets are modified to give more accurate linear magnetic flux densities and the shape and shape of the magnets of an anisotropic square shape The result is almost identical to the graph, and the linearity can be found in the change of magnetic flux density with distance in the 2-10 section, which is the effective section of the actual magnet. It is possible to become a magnet having a linear magnetic flux density along a straight line connecting the start point (section 2) and the end point (section 10) of the above valid section.

7 is a cross-sectional view of a precise pressure sensor using a magnet releasing a linear magnetic flux density according to the present invention, Figure 8 is a side view of a precise pressure sensor using a magnet releasing a linear magnetic flux density according to the present invention, 9 shows a plan view of a precise pressure sensor using a magnet that emits a linear magnetic flux density according to the present invention.

The pressure sensor has an inner space where the upper case 72 and the lower case 72 are engaged with each other, and the diaphragm 66 is fitted between the upper case 72 and the lower case 72 so that the internal space is divided into two compartments. It has a combined configuration.

The lower portion of the diaphragm 66 is formed with a coupler 64 to closely couple the diaphragm support 62 and the diaphragm 66 so that the diaphragm support 62 and the diaphragm 66 move in association with the pressure change. The lower side of the diaphragm support 62 is coupled to a magnet 60 that emits a linear magnetic flux density along a straight line connecting the start point and the end point, and the pole surface of the N pole or the S pole of the magnet 60 is It is the same as the moving direction of the diaphragm 66 and is arranged parallel to the magnetic sensor (Programmable Hall IC) 68 at a predetermined distance.

The magnetic sensor 68 is connected to the PCB 70 is to deliver the pressure information to the controller according to the purpose of using the pressure sensor for the electrical output.

The spring 82 disposed below the diaphragm support 62 serves to balance the positive pressure and the negative pressure, and the pressure to which the diaphragm 66 is added to the positive pressure connecting portion 94 and the negative pressure connecting portion 92. It is moved upwards or downwards according to the difference, and as the positive pressure is greater than the negative pressure, that is, there is a difference in the distance that the spring 82 deforms according to the difference in pressure. The magnetic sensor (Programmable Hall IC) 68 is to detect the absolute deformation position by measuring the magnetic flux density that changes linearly generated by the magnet (60).

As described above, the precise pressure sensor according to the present invention has been described, but the scope of the present invention is not limited thereto, and it will be said that the technical spirit of the range equivalent to the matters described in the claims is equivalent.

The present invention solves the problem of inaccurate control due to inaccurate position information of position sensors using a conventional magnet in a precision control device that performs precise control by detecting pressure to derive a precise pressure difference according to a change in distance. The pressure sensor enables more precise control.

1 is a cross-sectional view of a pressure sensor using light of the prior art,

2 is a cross-sectional view of a pressure sensor using a magnet of the prior art,

3 is a cross-sectional view of a pressure sensor using a plurality of magnets of the prior art,

4 is a view showing the magnetized shape and the shape of the magnet according to the present invention,

Figure 5 shows the shape and magnetized shape of the magnet according to another embodiment of the present invention,

Figure 6 is a graph showing the magnetic flux density change of the triangle and rectangle according to the present invention,

7 is a cross-sectional view of a precise pressure sensor using a magnet that emits a linear magnetic flux density according to the present invention,

8 is a side view of a precise pressure sensor using a magnet that emits a linear magnetic flux density according to the present invention,

9 is a plan view of a precise pressure sensor using a magnet for emitting a linear magnetic flux density according to the present invention.

Explanation of symbols on the main parts of the drawings

60: magnet 62: diaphragm support 64: coupling portion

66: diaphragm 68: magnetic sensor (Programmable Hall IC)

70: PCB 72: upper case 74: lower case

82: spring 92: negative pressure connection 94: positive pressure connection

A: start point B: end point

C: starting point of square magnet D: ending point of square magnet

Claims (6)

In the pressure sensor, The magnet consists of a square shape, N and S poles are magnetized in a sin waveform along the diagonal line diagonally from the corners of the rectangle, and are separated by a certain distance from the pole surface of the magnet and are parallel to the pole surface of the magnet (CD) (CD: C1-D1, C2 Precision pressure sensor, characterized in that for detecting the pressure by measuring the displacement of the magnet having a linear magnetic flux density along -D2, C3-D3, C4-D4). The method of claim 1, As a starting point (C) to measure a point vertically spaced apart from the pole surface of the high end portion of the magnetized magnet density of the magnet pole of the N pole or the S pole of the magnet by a magnetic sensor, The end point (D) is measured by a magnetic sensor at a point spaced a certain distance from the pole surface of the start point (C) perpendicular to the start point (C). From the start point (C) to the end point (D) along a straight line parallel to the pole surface (line with start and end points: CD) (CD: C1-D1, C2-D2, C3-D3, C4-D4) Precise pressure sensor characterized in that it detects the pressure by measuring the displacement of the magnet that emits a linear magnetic flux density in the 2-10 section which is an effective section of the measurement section 0-12 in response to the moving distance change. The method of claim 2, The magnetic flux density of the N pole or the S pole, which is a component of the magnet, increases the distance d from the start point C to the end point D, so that the straight lines C1-D1, C2-D2, C3-D3, and C4-D4 respectively. Along the straight line C2-D2 to find a straight line (eg C2-D2) indicating the linearity of the magnetic flux density measured by the magnetic sensor relative to the moving distance of the magnetic sensor. Precise pressure sensor, characterized in that for detecting the pressure by measuring the density of the magnet in accordance with the distance change by measuring the density. The method of claim 3, The pressure sensor has a diaphragm support 62 coupled to the diaphragm 66, A magnet disposed on the diaphragm support 62 such that a straight line connecting the start point C2 and the end point D2 for measuring the magnetic flux density of the magnet with a magnetic sensor is perpendicular to the operation direction of the diaphragm 66; A magnetic sensor 68 which senses the magnetic flux density of the magnet, coincides with a straight line connecting the start point C2 and the end point D2 to measure the magnetic flux density of the magnet with a magnetic sensor, and is disposed perpendicular to the lower surface of the lower plate case; , And a spring 82 installed between the diaphragm support 62 and the lower surface of the lower plate case. And a diaphragm 66 for dividing the inner space formed by the lower plate case and the upper plate case into two compartments. A positive pressure connecting portion communicating with the upper compartment and a negative pressure connecting portion communicating with the lower compartment of the two compartments; Precision pressure sensor, characterized in that for detecting the pressure by measuring the relative displacement of the magnet coupled to the diaphragm support (62) in accordance with the vertical movement of the diaphragm (66). In the precise pressure sensor, The magnet has a higher right side than the left side, and the upper side has a rectangular shape formed by diagonal lines. As a starting point (A) for measuring a point vertically spaced apart from the pole surface of the right end point of the pole surface, which is a high density magnetized magnet of the N pole or the S pole, by a magnetic sensor, It is set as the end point (B: B1, B2, B3, B4) measured by the magnetic sensor at a point spaced vertically from the pole surface of the left end point of the pole surface, which is a part of the magnetized magnet with low density. Each distance for measuring the magnetic flux density with a magnetic sensor along a straight line connecting the start point (A) and the end point (B: B1, B2, B3, B4) is a measurement section, and is a nonlinear measurement section from 0-12 sections. Precise pressure sensor, characterized in that for detecting the pressure by measuring the displacement of the magnet having a linear magnetic flux density in the section 2-10, except the edge section that can represent the sex. The method of claim 5, Precise pressure sensor, characterized in that the north pole and the south pole, which is a component of the magnet consists of a magnet magnetized to a metal having a ratio of 1 to 1.5 to the width of the left side to the right side.

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