Contact pressure sensor

Abstract

An embodiment of the present invention discloses a contact-type pressure sensor. The contact-type pressure sensor includes a housing, a first magnetic induction component, a first pressure rod, and a transmission integrated module. The housing has a housing cavity, and the first magnetic induction component is disposed within the housing cavity. The first magnetic induction component includes a first supermagnetic rod, a first permanent magnet, and a first magnetic conductive cylinder. The first supermagnetic rod is cantilevered within the housing, the first permanent magnet is sleeved on the first supermagnetic rod, and the first magnetic conductive cylinder is sleeved on the first permanent magnet. The first pressure rod has a first end and a second end disposed along its length, the first end abutting against the side wall of the first supermagnetic rod, and the second end of the first pressure rod extends out of the housing. The first pressure rod is movable along the length of the first pressure rod. Therefore, the contact-type pressure sensor of the embodiment of the present invention has the advantages of high sensitivity, small size, low cost, and no need for power supply.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular to a contact type pressure sensor. Background Art

[0002] The problems of high stress in deep rock masses and disasters caused by engineering disturbances are becoming increasingly prominent. During the construction of deep engineering projects, disasters such as surrounding rock instability, impact ground pressure, rock bursts, and water inrush occur frequently, posing new challenges to related rock mechanics theories and stress testing technologies.

[0003] Capacitive pressure sensors are commonly used, but due to their susceptibility to interference from external signals and inherent parasitic capacitance, nonlinearity issues remain difficult to effectively address. Resistive strain gauge pressure sensors utilize a strain gauge bonded to a test specimen or elastic sensor. The physical properties of the adhesive directly affect the characteristics of the strain gauge, leading to measurement errors. Fiber Bragg grating (FBG) stress sensors are also commonly used, but they suffer from low strength, fragility, and excessive temperature sensitivity. Summary of the Invention

[0004] The present invention aims to at least partially address one of the technical problems in the related art. To this end, embodiments of the present invention provide a contact-type pressure sensor. This contact-type pressure sensor has the advantages of high sensitivity, small size, low cost, and no need for power supply.

[0005] The contact pressure sensor according to the embodiment of the present invention includes a housing, a first magnetic induction component, a first pressure rod, and a transmission integrated module.

[0006] The housing has a housing cavity, and a first magnetic induction assembly is disposed within the housing cavity. The first magnetic induction assembly includes a first super magnetobar, a first permanent magnet, and a first magnetic conductive cylinder. One end of the first super magnetobar is connected to the housing, and the other end of the first super magnetobar extends toward the interior of the housing cavity. The first permanent magnet is sleeved onto the first super magnetobar, and the first magnetic conductive cylinder is sleeved onto the first permanent magnet. A first pressure rod has a first end and a second end disposed along its length, the first end abutting the sidewall of the other end of the first super magnetobar, and the second end of the first pressure rod extends outside the housing. The first pressure rod is movable along its length. The transmission integrated module includes a first Hall sensor for detecting Hall voltage to convert the stress signal of the first pressure rod into an electrical signal. It will be understood that the first super magnetobar is cantilevered within the housing cavity.

[0007] In the contact pressure sensor of the embodiment of the present invention, by abutting the first end of the first pressure rod against the side wall of the other end of the first giant magnetobar, it can be understood that the first pressure rod and the first giant magnetobar are arranged non-parallel (cantilever beam arrangement).

[0008] The contact-type pressure sensor of an embodiment of the present invention employs a cantilever beam arrangement for the first pressure rod and the first giant magnetobar. Compared to a first giant magnetobar of the same size, a cantilever beam arrangement in which the first pressure rod and the first giant magnetobar are arranged parallel to each other (a pressure-rod arrangement) exhibits a greater deformation when subjected to the same stress. This deformation of the first giant magnetobar is positively correlated with the sensitivity of the pressure sensor. Consequently, the contact-type pressure sensor of an embodiment of the present invention exhibits a high sensitivity.

[0009] Similarly, under the same sensitivity, the length of the giant magnetobar arranged in a compression rod type is longer than that in a cantilever beam type, thereby greatly reducing the manufacturing cost of the contact pressure sensor 100.

[0010] Furthermore, the contact pressure sensor of the present invention utilizes supermagnetic material as its force-sensitive element. This offers advantages such as a wide measuring range, high precision, excellent temperature stability, and strong fatigue resistance. This further enhances the measuring range and precision of the contact pressure sensor.

[0011] Furthermore, the contact-type pressure sensor of the present invention uses a permanent magnet as the first magnetobar to provide a constant magnetic field. Compared to coils, this method offers advantages such as low heat generation and compact size. Furthermore, using a permanent magnet to provide the magnetic field for the first magnetobar eliminates the need for a power supply.

[0012] Therefore, the contact pressure sensor of the embodiment of the present invention has the advantages of high sensitivity, small size, low cost and no need for power supply, which meets the requirements of lightweight, portability and long-term performance of the contact pressure sensor.

[0013] In some embodiments, the first plunger includes a first main body and a first tip. The first tip is disposed at the second end of the first plunger, and the first main body abuts against a side wall of the other end of the first giant magnetorod.

[0014] In some embodiments, the contact-type pressure sensor further includes a first spring piece, the shell has a first through hole for the first pressure rod to pass through, the first spring piece covers the area on the shell having the first through hole, a first cavity is formed between the first spring piece and the shell, and the first tip portion abuts against the first spring piece.

[0015] In some embodiments, the contact-type pressure sensor further includes a first positioning member, and the first positioning member is disposed in the first through hole.

[0016] In some embodiments, the first giant magnetobar is cylindrical, the first permanent magnet is cylindrical, and the length of the first giant magnetobar is equal to 1-1.5 times the diameter of the first giant magnetobar.

[0017] In some embodiments, the first magnetic induction component further includes a magnetic isolation cylinder, which is disposed in the accommodating cavity. The magnetic isolation cylinder includes a first magnetic isolation body, a first end cover and a second end cover. The magnetic isolation cylinder is sleeved on the first magnetic conductive cylinder, and the first end cover and the second end cover are respectively disposed at both ends of the first magnetic isolation body.

[0018] In some embodiments, the transmission integrated module includes a processor, a SIM card, and a transmitting antenna, and the first Hall sensor is connected to the processor, and the processor and the transmitting antenna are connected in sequence.

[0019] In some embodiments, the contact-type pressure sensor further includes a second magnetic induction component, a second pressure rod and a second Hall sensor, wherein the second magnetic induction component is arranged in the accommodating cavity, the second magnetic induction component includes a second super magnetobar, a second permanent magnet and a second magnetic conductive cylinder, one end of the second super magnetobar is connected to the shell, and the other end of the second super magnetobar extends toward the interior of the accommodating cavity, the second permanent magnet is sleeved on the second super magnetobar, and the second magnetic conductive cylinder is sleeved on the second permanent magnet, the second pressure rod can move along the length direction of the second pressure rod, one end of the second pressure rod abuts against the side wall of the other end of the second super magnetobar, and the second Hall sensor is arranged at one end of the first super magnetobar.

[0020] In some embodiments, the contact-type pressure sensor further includes a third magnetic induction component, a third pressure rod, and a third Hall sensor. The third magnetic induction component is disposed in the accommodating cavity. The third magnetic induction component includes a third super magnetobar, a third permanent magnet, and a third magnetic conductive cylinder. One end of the third super magnetobar is connected to the shell, and the other end of the third super magnetobar extends toward the interior of the accommodating cavity. The third permanent magnet is sleeved on the third super magnetobar, and the third magnetic conductive cylinder is sleeved on the third permanent magnet. The third pressure rod can move along the length direction of the third pressure rod, and one end of the third pressure rod abuts against the side wall of the other end of the third super magnetobar or the end of the third super magnetobar. The third Hall sensor is disposed at one end of the first super magnetobar.

[0021] In some embodiments, the first giant magnetorand, the second giant magnetorand, and the third giant magnetorand are arranged in parallel, or the third giant magnetorand is arranged in parallel with each of the first giant magnetorand and the second giant magnetorand, and the first pressure rod, the second pressure rod, and the third pressure rod are arranged orthogonally to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. 4 is a schematic structural diagram of a contact-type pressure sensor according to an embodiment of the present invention.

[0023] Figure 2 yes Figure 1 Cross-section along the AA direction.

[0024] Figure 3 yes Figure 1 Another cross-sectional view along the AA direction.

[0025] Figure 4 yes Figure 1 Cross-sectional view along direction BB.

[0026] Reference numerals:

[0027] Contact type pressure sensor 100;

[0028] Housing 1; Accommodation chamber 11;

[0029] First magnetic induction component 2; first super magnetobar 21; first permanent magnet 22; first magnetic conductive cylinder 23; magnetic isolation cylinder 24;

[0030] First pressure rod 3; first main body portion 31; first tip portion 32;

[0031] Second magnetic induction component 4; second super magnetobar 41; second permanent magnet 42; second magnetic conductive cylinder 43;

[0032] Second pressure rod 5; second main body portion 51; second tip portion 52;

[0033] The third magnetic induction component 6; the third super magnetobar 61; the third permanent magnet 62; the third magnetic conductive cylinder 63;

[0034] The third pressure rod 7; the third main body portion 71; the third tip portion 72;

[0035] A first Hall sensor 81; a second Hall sensor (not shown); a third Hall sensor 83;

[0036] A first spring piece 91; a second spring piece (not shown); a third spring piece 93;

[0037] First positioning member 101. DETAILED DESCRIPTION

[0038] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0039] Reference below Figure 1-Figure 4 A contact-type pressure sensor 100 according to an embodiment of the present invention will be described.

[0040] The contact pressure sensor 100 according to the embodiment of the present invention includes a housing 1 , a first magnetic induction component 2 , a first pressure rod 3 and a transmission integrated module.

[0041] The housing 1 has a housing cavity 11, and the first magnetic induction component 2 is arranged in the housing cavity 11. The first magnetic induction component 2 includes a first super magnetobar 21, a first permanent magnet 22 and a first magnetic conductive cylinder 23. One end of the first super magnetobar 21 is connected to the housing 1, and the other end of the first super magnetobar 21 extends toward the interior of the housing cavity 11. The first permanent magnet 22 is sleeved on the first super magnetobar 21, and the first magnetic conductive cylinder 23 is sleeved on the first permanent magnet 22. The first pressure rod 3 (used to transmit pressure between the super magnetobar and the test object, for example, the test object can be a drill hole) has a first end and a second end arranged along its length direction. The first end of the first pressure rod 3 is connected to the other end of the first super magnetobar 21 (for example, Figure 1 The first pressure rod 3 abuts against the side wall of the housing 1 (the right end shown in FIG). The second end of the first pressure rod 3 extends outside the housing 1. The first pressure rod 3 is movable along the length of the first pressure rod 3. The transmission integrated module includes a first Hall sensor 81 for detecting Hall voltage to convert the stress signal of the first pressure rod 3 into an electrical signal. The first end of the first pressure rod 3 abuts against the side wall of the cantilever end of the first giant magnetorand 21. It can be understood that the first pressure rod 3 and the first giant magnetorand 21 are arranged non-parallel (cantilever beam arrangement), and the first giant magnetorand 21 is cantilevered within the accommodating cavity 11. The magnetorand is also called a magnetostrictive rod.

[0042] The contact-type pressure sensor 100 of the present embodiment employs a cantilever beam arrangement for the first pressure rod 3 and the first giant magnetobar 21. With respect to the first giant magnetobar 21 of the same size, the first pressure rod 3 is arranged parallel to the first giant magnetobar 21 (a cantilever arrangement). In other words, one end of the first pressure rod 3 abuts one end of the cantilever of the first giant magnetobar 21. When subjected to the same stress, the cantilever beam structure of the first giant magnetobar 21 exhibits significant deformation. The deformation of the first giant magnetobar 21 is positively correlated with the sensitivity of the pressure sensor. Consequently, the contact-type pressure sensor 100 of the present embodiment exhibits high sensitivity.

[0043] Similarly, under the condition of the same sensitivity, the length of the giant magnetobar in the pressure rod arrangement needs to be longer than that in the cantilever beam arrangement. This greatly reduces the manufacturing cost of the contact pressure sensor 100. For example, when the cantilever beam arrangement is used, under the condition of the same sensitivity requirement, the size of the giant magnetobar in the pressure rod arrangement needs to be Φ10x10mm, and the size of the giant magnetobar in the cantilever beam arrangement needs to be Φ50x10mm. The density of the first giant magnetobar 21 is 9.25g / cm 3The first giant magnetorand 21 costs an average of 100 yuan per gram, saving 545 yuan per first giant magnetorand 21. The contact-type pressure sensor 100 requires three giant magnetorands, saving approximately 1,500 yuan per sensor. This significantly reduces the manufacturing cost of the sensor. The cantilever beam design allows the giant magnetorand to be relatively small. This saves space within the housing cavity and reduces the overall size of the contact-type pressure sensor 100.

[0044] Furthermore, the contact pressure sensor 100 of the embodiment of the present invention uses a supermagnetic material as a force-sensitive element, which has the advantages of a large measurement range, high accuracy, good temperature stability, and strong fatigue resistance. Therefore, the contact pressure sensor 100 of the embodiment of the present invention has the advantages of further improving the measurement range and accuracy.

[0045] Furthermore, the contact-type pressure sensor 100 of the present invention employs a permanent magnet as the first giant magnetobar 21 to provide a constant magnetic field. Compared to methods using coils as magnetic sources, this sensor offers advantages over heat generation and a smaller size. Furthermore, the use of a permanent magnet to provide the magnetic field for the first giant magnetobar 21 eliminates the need for a power source, enabling passive wireless detection of rock stress.

[0046] Therefore, the contact pressure sensor 100 of the embodiment of the present invention has the advantages of high sensitivity, small size, low cost and no need for power supply, which meets the requirements of lightweight, portability and long-term use of the contact pressure sensor 100.

[0047] Optionally, first Hall sensors 81 are installed at both ends of the first super magnetotropic rod 21. The two first Hall sensors 81 receive the same pressure, and by comparing the working status of the data of the two first Hall sensors 81, the overall working status of the sensor is judged to check whether there are special situations such as leakage magnetic field, magnetic runaway or other electromagnetic interference.

[0048] like Figure 1 and Figure 2 As shown, the first pressure rod 3 includes a first main body portion 31 and a first tip portion 32. The first tip portion 32 extends to the outside of the shell 1. The first main body portion 31 is arranged at the second end of the first pressure rod 3, and the first main body portion 31 abuts against the side wall (circumferential wall) of the other end of the first super magnetobar 21.

[0049] The contact-type pressure sensor 100 of the present embodiment utilizes a first tip portion 32 provided on the first pressure rod 3, which reduces the contact area between the first pressure rod 3 and the rock mass. Consequently, under a constant stress on the first tip portion 32, the force exerted by the first pressure rod 3 on the first giant magnetobar 21 is reduced, thereby reducing the deformation of the first giant magnetobar 21 and further enhancing the measuring range of the contact-type pressure sensor 100. Consequently, the contact-type pressure sensor 100 of the present embodiment maintains both sensor sensitivity and a wide stress detection range.

[0050] Optionally, the first compression rod 3 may be a non-magnetic alloy rod, which has the advantages of high rigidity and no deformation.

[0051] like Figure 2 and Figure 3 As shown, the contact-type pressure sensor 100 further includes a first spring piece 91. The housing 1 has a first through-hole for the first pressure rod 3 to pass through. The first spring piece 91 covers the area of ​​the housing 1 having the first through-hole. A first cavity is formed between the first spring piece 91 and the housing 1. The first tip portion 32 abuts against the first spring piece 91. It will be understood that the side of the first spring piece 91 close to the housing 1 is an upwardly convex curved surface.

[0052] In the contact-type pressure sensor 100 according to the embodiment of the present invention, the first spring piece 91 is provided to encapsulate the first tip portion 32. Furthermore, the first spring piece 91 can deform in accordance with the contact area between the first tip portion 32 and the rock mass. This prevents the first tip portion 32 of the first pressure rod 3 from embedding in the rock mass and affecting the normal operation of the sensor.

[0053] like Figure 2 and Figure 3 As shown, the contact type pressure sensor 100 further includes a first positioning member 101 . The housing 1 has a first through hole for the first pressure rod 3 to pass through, and the first positioning member 101 is disposed in the first through hole.

[0054] The contact-type pressure sensor 100 of the embodiment of the present invention can fix and limit the first pressure rod 3 by providing the first positioning member 101, thereby preventing the first pressure rod 3 from losing contact with the first giant magnetobar 21 or even falling off the housing 1; and can further limit the movement trajectory of the first pressure rod in the longitudinal direction.

[0055] Optionally, the first positioning member 101 may be a butterfly spring.

[0056] Optionally, the first elastic sheet 91 may be a flexible elastic sheet.

[0057] like Figure 2 and Figure 4As shown, the first giant magnetobar 21 is cylindrical, the first permanent magnet 22 is cylindrical, and the length of the first giant magnetobar 21 is equal to 1-1.5 times the diameter of the first giant magnetobar 21.

[0058] The contact type pressure sensor 100 of the embodiment of the present invention can improve the constancy and uniformity of the magnetic field of the first permanent magnet 22 by configuring the first permanent magnet 22 to be cylindrical, thereby further improving the accuracy of the contact type pressure sensor 100.

[0059] In addition, the contact-type pressure sensor 100 of the embodiment of the present invention sets the length of the first giant magnetobar 21 to be 1-1.5 times the diameter of the first giant magnetobar 21 , thereby improving the sensitivity of the contact-type pressure sensor 100 .

[0060] like Figure 2 and Figure 4 As shown, the contact type pressure sensor 100 further includes a magnetic isolation tube 24, which is disposed in the accommodating cavity. The magnetic isolation tube 24 includes a first magnetic isolation body, a first end cover, and a second end cover. The magnetic isolation tube 24 is sleeved on the first magnetic conductive tube 23, and the first end cover and the second end cover are respectively disposed at both ends of the first magnetic isolation body. For example, Figure 3 The left and right ends of the first magnetic shielding body shown in .

[0061] The contact type pressure sensor 100 of the embodiment of the present invention can avoid magnetic interference and magnetic leakage by providing the magnetic isolation tube 24, thereby further improving the measurement accuracy of the contact type pressure sensor 100.

[0062] like Figure 2 and Figure 3 As shown, the transmission integrated module includes the first Hall sensor, a processor, a SIM card and a transmitting antenna. The first Hall sensor is connected to the processor, and the processor and the transmitting antenna are connected in sequence.

[0063] The contact pressure sensor 100 of an embodiment of the present invention utilizes a Hall effect sensor connected to a processor. The processor is connected to a SIM card via a serial port, and the SIM card is connected to a transmitting antenna. The Hall effect sensor converts the pressure signal into a voltage signal. The processor processes the voltage value of the Hall effect sensor and converts the analog signal into a digital signal. The SIM card labels the stress data obtained by each Hall effect sensor. The transmitting antenna can wirelessly transmit the stress information to the roadway network.

[0064] Alternatively, the processor may be a port-connected microprocessor.

[0065] The magnetic induction intensity of the permanent magnet; and use this to determine the outer diameter of the permanent magnet,

[0066] I'=M s =J0 / μ0=B r / μ0;

[0067] dI=M s dh;

[0068]

[0069] B z =μ0 / 2×M s ×{(Z+L) / [a 2 +(Z+L) 2 ] 1 / 2 -(ZL) / [a 2 +(ZL) 2 ] 1 / 2};

[0070] Among them, M s represents the saturation magnetization of the permanent magnet, B r The ordinate value represents the intersection of the BH demagnetization curve of the permanent magnet and the ordinate axis, and μ0 represents the vacuum permeability, which is 4π×10 -7 H / m; the current intensity dI of each sub-bound surface current is, a represents the radius of the cylindrical surface outside the circular permanent magnet; ρ represents the value of the coordinate ρ of the calculation point P; Z represents the value of the coordinate Z of the calculation point P; L represents half the thickness of the circular permanent magnet; K(k) and E(k) represent the Legendre complete elliptic integral of the first kind and the Legendre complete elliptic integral of the second kind with module k, respectively; h represents the distance from the calculation point P to the plane where the sub-bound surface current is located.

[0071] Therefore, the rock stress detection system disclosed in the present invention realizes self-supply of electric energy, does not require external power supply to provide electric energy, realizes passive wireless detection of rock stress, and has the characteristics of large coverage, low cost, and long-term stable detection, meeting the needs of lightweight, portability, and long-term performance.

[0072] like Figure 1 and Figure 4 As shown, the contact-type pressure sensor 100 further includes a second magnetic induction component 4, a second pressure rod 5 and a second Hall sensor (not shown). The second magnetic induction component 4 is arranged in the accommodating cavity 11. The second magnetic induction component 4 includes a second super magnetobar 41, a second permanent magnet 42 and a second magnetic conductive cylinder 43. One end of the second super magnetobar 41 is connected to the shell 1, and the other end of the second super magnetobar 41 extends toward the interior of the accommodating cavity 11. The second permanent magnet 42 is sleeved on the second super magnetobar 41, and the second magnetic conductive cylinder 43 is sleeved on the second permanent magnet 42. The second pressure rod 5 can move along the length direction of the second pressure rod 5, and one end of the second pressure rod 5 abuts against the side wall of the other end of the second super magnetobar 41. The second Hall sensor is arranged at one end of the first super magnetobar 21.

[0073] The contact type pressure sensor 100 of the embodiment of the present invention can measure stress at multiple points in a rock formation by providing the second magnetic induction component 4 , thereby achieving the advantage of accurate stress measurement.

[0074] like Figure 1 and Figure 2 As shown, the second pressure rod 5 includes a second main body portion 51 and a second tip portion 52 . The second main body portion 51 is provided at the second end of the second pressure rod 5 , and the second main body portion 51 abuts against the side wall of the other end of the second giant magnetorand 41 .

[0075] The contact-type pressure sensor 100 of the embodiment of the present invention utilizes a second tip portion 52 provided on the second pressure rod 5. This tip portion 52 reduces the contact area between the second pressure rod 5 and the rock mass. Thus, while maintaining the same stress on the second tip portion 52, the force exerted by the second pressure rod 5 on the second giant magnetobar 41 is reduced, thereby reducing the deformation of the second giant magnetobar 41. Therefore, the contact-type pressure sensor 100 has the advantage of further increasing its measuring range. Thus, the contact-type pressure sensor 100 of the embodiment of the present invention maintains both sensor sensitivity and a wide stress detection range.

[0076] like Figure 1 and Figure 4 As shown, the contact-type pressure sensor 100 further includes a third magnetic induction component 6, a third pressure rod 7 and a third Hall sensor 83. The third magnetic induction component 6 is arranged in the accommodating cavity 11. The third magnetic induction component 6 includes a third super magnetobar 61, a third permanent magnet 62 and a third magnetic conductive cylinder 63. One end of the third super magnetobar 61 is connected to the shell 1, and the other end of the third super magnetobar 61 extends toward the interior of the accommodating cavity 11. The third permanent magnet 62 is sleeved on the third super magnetobar 61, and the third magnetic conductive cylinder 63 is sleeved on the third permanent magnet 62. The third pressure rod 7 can move along the length direction of the third pressure rod 7, and one end of the third pressure rod 7 abuts against the side wall of the other end of the third super magnetobar 61. The third Hall sensor 83 is arranged at one end of the first super magnetobar 21.

[0077] The contact-type pressure sensor 100 of the embodiment of the present invention can measure stress at multiple points in a rock formation by providing the third magnetic induction component 6 , which has the advantage of further improving the accuracy of stress measurement.

[0078] The embodiments of the present invention are not limited thereto. In some embodiments, one end of the third pressure rod 7 abuts against the end of the third giant magnetobar 61 , and the third Hall sensor 83 is provided at one end of the first giant magnetobar 21 .

[0079] like Figure 1 and Figure 4As shown, the third pressure rod 7 includes a third main body portion 71 and a third tip portion 72 . The third main body portion 71 is provided at the second end of the third pressure rod 7 , and abuts against the side wall of the other end of the third giant magnetobar 61 .

[0080] The contact-type pressure sensor 100 of the embodiment of the present invention utilizes a third tip portion 72 provided on the third pressure rod 7. This tip portion 72 reduces the contact area between the third pressure rod 7 and the rock mass. Consequently, while maintaining the same stress on the third tip portion 72, the force exerted by the third pressure rod 7 on the third giant magnetobar 61 is reduced, thereby reducing the deformation of the third giant magnetobar 61. Therefore, the contact-type pressure sensor 100 has the advantage of further increasing its measuring range. Thus, the contact-type pressure sensor 100 of the embodiment of the present invention maintains both sensor sensitivity and a wide stress detection range.

[0081] like Figure 3 and Figure 4 As shown, the first giant magnetobar 21, the second giant magnetobar 41 and the third giant magnetobar 61 are arranged in parallel, and the first pressure rod 3, the second pressure rod 5 and the third pressure rod 7 are arranged orthogonally to each other.

[0082] Optionally, the contact pressure sensor 100 according to the embodiment of the present invention further includes a second elastic piece and a third elastic piece 93 . The second elastic piece abuts against the second tip portion 52 , and the third elastic piece 93 abuts against the third tip portion 72 .

[0083] The present application is not limited to this. For example, in other embodiments, the third giant magnetobar 61 is arranged parallel to each of the first giant magnetobar 21 and the second giant magnetobar 41, and the first pressure rod 3, the second pressure rod 5 and the third pressure rod 7 are arranged orthogonally to each other.

[0084] For example, the first pressure rod 3 extends along the X direction, the second pressure rod 5 extends along the Y direction, and the third pressure rod 7 extends along the Z direction. Pressure is transmitted to the corresponding pressure rods in the three perpendicular directions of X, Y, and Z respectively.

[0085] The working principle of the contact pressure sensor 100 according to the embodiment of the present invention is as follows:

[0086] For example, the object to be tested is a rock mass, and drilling is performed within the rock mass to obtain a borehole. A circular borehole is drilled into the rock mass to a specified depth. The size of the borehole is coupled to (size-matched with) the size of the contact-type pressure sensor 100, but the circular borehole size is slightly larger than the size of the contact-type pressure sensor 100. The borehole is probed and deslagging is performed, and the contact-type pressure sensor 100 is installed at the bottom of the borehole. Grouting is performed at the bottom of the contact-type pressure sensor 100. The grouting slurry fills the gap between the contact-type pressure sensor 100 and the borehole wall. A certain length of grout is injected into the contact-type pressure sensor 100, sealing the contact-type pressure sensor 100 in the borehole and restricting the contact-type pressure sensor 100 from sliding within the borehole. When the pressure around the contact-type pressure sensor 100 changes, the circular borehole is squeezed and deformed, transmitting pressure to the corresponding pressure rod in the three perpendicular directions of X, Y, and Z.

[0087] Corresponding cylindrical permanent magnets (first permanent magnet 22, second permanent magnet 42, or third giant magnetobar 61) generate a constant magnetic field strength H. The cylindrical permanent magnets enclose the corresponding giant magnetobar, generating an induced magnetic field strength B within and around the giant magnetobar. According to the principle of the inverse magnetostrictive effect, under the influence of external pressure, the axial stress σ of the giant magnetobar changes, causing a change in the giant magnetobar's magnetic permeability μ. This change in magnetic permeability μ further causes a change in the induced magnetic field strength B.

[0088] When the giant magnetorod works under constant temperature conditions, its piezomagnetic equation is:

[0089] ε=s H σ+dH (1)

[0090] B=dσ+μ σ H (2)

[0091] Where: strain ε, stress σ, magnetic field intensity H, magnetic flux density B, magnetostrictive strain coefficient (piezomagnetic coefficient) d, compliance coefficient s under constant magnetic field H and the magnetic permeability μ under constant stress σ ;

[0092] The relationship between the internal stress σ and the magnetic induction intensity B of the giant magnetorod is obtained by equations (1) and (2):

[0093] B=σ(d-μ σ s H / d)+μ σ ε / d (3)

[0094] The Hall sensor (first Hall sensor 81, second Hall sensor, or third Hall sensor 83) can measure the induced magnetic field strength B. When a DC current is passed through the Hall sensor and placed in the induced magnetic field (magnetic induction strength B), an induced electromotive force U is generated within the Hall sensor. According to the operating principle of the Hall sensor, its output Hall voltage is U = KB, where K is the sensitivity coefficient of the Hall sensor. Therefore, the relationship between the Hall voltage and the axial stress σ of the giant magnetorot is obtained as follows:

[0095] U=Kσ(d-μ σ s H / d)+Kμ σ ε / d (4)

[0096] External pressure F in X direction X , external pressure F in Y direction y External pressure F in Z direction Z , the supermagnetic rod is a cantilever beam structure. At this time, in F X 、F y and F Z The force analysis of the giant magnetobar under external pressure assumes that the cantilever beam structure rotates at an angle of θ under external pressure. Since the giant magnetobar has a large stiffness, the angle θ is generally small. The average axial stress of the giant magnetobar is:

[0097]

[0098] In formula (5), S is the cross-sectional area of ​​the giant magnetorod, E is the elastic modulus of the giant magnetorod, and I is the moment of inertia of the giant magnetorod, =πd 4 / 64.

[0099] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0100] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0101] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0102] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0103] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0104] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A contact type pressure sensor, characterized in that: include: a housing, wherein the housing has a receiving cavity; a first magnetic induction component, which is disposed in the accommodating cavity and includes a first super magnetobar, a first permanent magnet, and a first magnetic conductive cylinder, wherein one end of the first super magnetobar is connected to the housing, and the other end of the first super magnetobar extends toward the interior of the accommodating cavity, the first permanent magnet is sleeved on the first super magnetobar, and the first magnetic conductive cylinder is sleeved on the first permanent magnet; a first pressure rod, the first pressure rod having a first end and a second end arranged along its length, the first end abutting against a side wall of the other end of the first giant magnetorand, the second end of the first pressure rod extending out of the housing, and the first pressure rod being movable along its length; a transmission integrated module, the transmission integrated module including a first Hall sensor, wherein the first Hall sensor is installed at both ends of the first super magnetostrictive rod, the two first Hall sensors receive the same pressure, and the overall working state of the sensor is determined by comparing the working states of the two first Hall sensors; The transmission integrated module further includes a processor, a SIM card and a transmitting antenna. The first Hall sensor is connected to the processor, and the processor and the transmitting antenna are connected in sequence.

2. The contact type pressure sensor according to claim 1, wherein: The first compression rod includes a first main body and a first tip. The first tip extends to the outside of the shell. The first main body abuts against a side wall of the other end of the first giant magnetobar.

3. The contact type pressure sensor according to claim 2, wherein: It also includes a first elastic sheet, the shell has a first through hole for the first pressure rod to pass through, the first elastic sheet covers the area of ​​the shell having the first through hole, a first cavity is formed between the first elastic sheet and the shell, and the first tip portion abuts against the first elastic sheet.

4. The contact type pressure sensor according to claim 3, wherein: It also includes a first positioning member, which is arranged in the first through hole.

5. The contact type pressure sensor according to claim 1, wherein: The first giant magnetobar is cylindrical, the first permanent magnet is cylindrical, and the length of the first giant magnetobar is equal to 1-1.5 times the diameter of the first giant magnetobar.

6. The contact pressure sensor according to any one of claims 1 to 5, characterized in that: The first magnetic induction component also includes a magnetic isolation tube, which is arranged in the accommodating cavity. The magnetic isolation tube includes a first magnetic isolation body, a first end cover and a second end cover. The magnetic isolation tube is sleeved on the first magnetic conductive tube, and the first end cover and the second end cover are respectively arranged at both ends of the first magnetic isolation body.

7. The contact type pressure sensor according to claim 1, wherein: It also includes a second magnetic induction component, a second pressure rod and a second Hall sensor. The second magnetic induction component is arranged in the accommodating cavity. The second magnetic induction component includes a second super magnetobar, a second permanent magnet and a second magnetic conductive cylinder. One end of the second super magnetobar is connected to the shell, and the other end of the second super magnetobar extends toward the interior of the accommodating cavity. The second permanent magnet is sleeved on the second super magnetobar, and the second magnetic conductive cylinder is sleeved on the second permanent magnet. The second pressure rod can move along the length direction of the second pressure rod, and one end of the second pressure rod abuts against the side wall of the other end of the second super magnetobar. The second Hall sensor is arranged at one end of the first super magnetobar.

8. The contact type pressure sensor according to claim 7, wherein: The invention also includes a third magnetic induction component, a third pressure rod and a third Hall sensor. The third magnetic induction component is arranged in the accommodating cavity. The third magnetic induction component includes a third super magnetobar, a third permanent magnet and a third magnetic conductive cylinder. One end of the third super magnetobar is connected to the shell, and the other end of the third super magnetobar extends toward the interior of the accommodating cavity. The third permanent magnet is sleeved on the third super magnetobar, and the third magnetic conductive cylinder is sleeved on the third permanent magnet. The third pressure rod can move along the length direction of the third pressure rod, and one end of the third pressure rod abuts against the side wall of the other end of the third super magnetobar or the end of the third super magnetobar. The third Hall sensor is arranged at one end of the first super magnetobar.

9. The contact type pressure sensor according to claim 8, wherein: The first, second and third giant magnetorands are arranged in parallel, or the third giant magnetorand is arranged in parallel with each of the first and second giant magnetorands, and the first, second and third pressure rods are arranged orthogonally to each other.

Images