Differential displacement sensor

Abstract

The invention discloses a differential displacement sensor, which belongs to the field of sensors and comprises a shell, and a support assembly, a detection assembly, a traction assembly and a lever assembly are arranged in the shell. The supporting assembly comprises a sleeve, and the sleeve is fixedly connected with the shell; the detection assembly comprises a secondary coil, a primary coil and an iron core, the iron core is inserted into the sleeve, and the sleeve is sleeved with the secondary coil and the primary coil; the lever assembly comprises a probe rod and a hinge shaft, the hinge shaft is fixedly connected with the shell, a hinge hole is formed in the probe rod, and the hinge shaft is inserted into the hinge hole in a penetrating mode. The traction assembly comprises a traction rope and a guide piece, the guide piece comprises a guide wheel and a supporting column, the supporting column is fixedly connected with the shell, the guide wheel is rotationally connected with the supporting column, the traction rope is wound on the peripheral face of the guide wheel, one end of the traction rope is connected with the iron core, the other end of the traction rope is connected with the probe rod, and therefore the measurement precision of the sensor can be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and particularly relates to a differential displacement sensor. Background Art

[0002] An LVDT (Linear Variable Differential Transformer) sensor is a sensor used to measure linear displacement, which has the characteristics of high precision, high reliability, and non-contact measurement. Common LVDT sensors are mainly pneumatic, integrated, lever-type, and spring-back type. Each structure provides different advantages and characteristics according to different application requirements and measurement environments.

[0003] Generally, a lever-type LVDT sensor includes a housing. Inside the housing, there are a lever, an iron core, and multiple coils. When the lever swings relative to the housing, it drives the iron core to move inside the coil. With this structure, based on the lever principle, when a relatively small force is applied to the input end of the lever, a relatively large torque can still be generated at the output end of the lever. Through this torque, the iron core can be pushed to move a relatively large displacement, thereby improving the sensitivity and accuracy of the sensor measurement. However, when the lever swings, the movement of its output end is an arc movement. When the output end of the lever drives the iron core to move, the iron core will deflect to a certain extent, resulting in a deviation between the movement trajectory of the iron core and the ideal linear trajectory. As a result, the magnetic field change experienced by the iron core during its movement is not uniform, and further a non-linear relationship appears between the output signal of the sensor and the actual displacement, affecting the measurement accuracy of the sensor. Summary of the Invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a differential displacement sensor. The technical problems to be solved by the present invention are realized through the following technical solutions:

[0005] In a first aspect, the present invention provides a differential displacement sensor, which includes a housing. Inside the housing, there are a support assembly, a detection assembly, a traction assembly, and a lever assembly;

[0006] The support assembly includes a sleeve, and the sleeve is fixedly connected to the housing;

[0007] The detection assembly includes a secondary coil, a primary coil, and an iron core. The iron core is inserted into the sleeve and is slidably connected to the sleeve. The secondary coil and the primary coil are both sleeved outside the sleeve. There are two secondary coils, and the two secondary coils are respectively arranged on both sides of the primary coil;

[0008] The lever assembly includes a probe rod and a hinge shaft. The hinge shaft is fixedly connected to the housing. There is a hinge hole on the probe rod, and the hinge shaft is inserted into the hinge hole. One end of the probe rod is inside the housing, and the other end extends outside the housing;

[0009] The traction assembly includes a traction rope and a guiding member. The guiding member includes a guiding wheel and a support column. The support column is fixedly connected to the housing. The guiding wheel is rotatably connected to the support column. The guiding wheel is disposed opposite to the open end of the sleeve. The traction rope is wound around the outer peripheral surface of the guiding wheel. One end of the traction rope is connected to the iron core, and the other end is connected to the probe rod.

[0010] In an embodiment of the present invention, the support assembly further includes a retaining piece and a first spring. The retaining piece is connected to the end of the iron core away from the traction rope. The retaining piece and the end face of the sleeve are in limit fit. The first spring is disposed between the retaining piece and the sleeve.

[0011] In an embodiment of the present invention, the housing includes a bottom plate and an annular side plate. The annular side plate is connected to the upper surface of the bottom plate. The bottom plate and the annular side plate jointly enclose a receiving groove.

[0012] The annular side plate includes a front plate, a rear plate, a first inclined plate, a second inclined plate, a first side plate, and a second side plate. The length of the front plate is less than that of the rear plate and the two are arranged in parallel. The projection of the front plate on the rear plate is located at the middle position of the rear plate. The first inclined plate and the second inclined plate are respectively connected to both sides of the front plate. The first side plate and the second side plate are respectively connected to both sides of the rear plate. The first inclined plate is connected to the first side plate, and the second inclined plate is connected to the second side plate.

[0013] A perforation is provided on the front plate. One end of the probe rod is located in the receiving groove, and the other end passes through the perforation and extends out.

[0014] In an embodiment of the present invention, the lever assembly further includes a second spring. One end of the second spring is connected to the probe rod, and the other end is connected to the inner wall of the annular side plate.

[0015] In an embodiment of the present invention, a connecting sleeve is provided on the outer surface of the front plate. The axis of the connecting sleeve is collinear with the axis of the perforation. Both ends of the hinge shaft are fixedly connected to the inner wall of the connecting sleeve. The axis direction of the hinge shaft is perpendicular to the axis direction of the connecting sleeve.

[0016] In an embodiment of the present invention, an annular groove is provided on the outer peripheral surface of the guiding wheel. The traction rope is embedded in the annular groove. The axis of the sleeve is tangent to the guiding wheel.

[0017] In an embodiment of the present invention, there are two guiding members. The two guiding members are sequentially arranged along the direction perpendicular to the axial direction of the sleeve. The traction rope is simultaneously wound around the outer peripheries of the guiding wheels in the two guiding members.

[0018] In an embodiment of the present invention, two support members are further provided between the sleeve and the bottom plate. The support members are fixedly connected to the bottom plate. The sleeve is fixedly connected to the support members. The two support members are symmetrically arranged at both ends of the sleeve along the axial direction of the sleeve.

[0019] In one embodiment of the present invention, the shell also includes a cover plate and a plug-in rod, the plug-in rod is fixedly connected to the lower surface of the cover plate, a support column is provided on the inner wall of the annular side plate, the bottom end of the support column is fixedly connected to the bottom plate, a plug-in groove is provided in the support column, and the plug-in rod and the plug-in groove are plug-in matched.

[0020] In one embodiment of the present invention, four support columns are provided;

[0021] Wherein, a support column is provided at the connection between the first inclined plate and the first side plate, a support column is provided at the connection between the second inclined plate and the second side plate, a support column is provided at the connection between the first side plate and the rear plate, and a support column is provided at the connection between the second side plate and the rear plate;

[0022] There are four plug-in rods, and the four plug-in rods correspond to the four plug-in slots respectively.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] In the above scheme of the present application, the differential displacement sensor includes a shell, in which a support assembly, a detection assembly, a traction assembly and a lever assembly are arranged; the support assembly includes a sleeve, and the sleeve is fixedly connected to the shell; the detection assembly includes a secondary coil, a primary coil and an iron core, the iron core is inserted into the sleeve, and the iron core and the sleeve are slidably connected, the secondary coil and the primary coil are both sleeved on the outside of the sleeve, two secondary coils are provided, and the two secondary coils are respectively arranged on both sides of the primary coil; the lever assembly includes a probe rod and an articulated shaft, the articulated shaft is fixedly connected to the shell, a hinge hole is provided on the probe rod, the articulated shaft is inserted into the articulated hole, one end of the probe rod is located in the shell, and the other end extends out of the shell; the traction assembly includes a traction rope and a guide member, the guide member includes a guide wheel and a pillar, the pillar is fixedly connected to the shell, the guide wheel and the pillar are rotatably connected, the guide wheel and the open end of the sleeve are arranged relative to each other, the traction rope is wound around the outer peripheral surface of the guide wheel, and one end of the traction rope is connected to the iron core, and the other end is connected to the probe rod. With this structure, when the lever swings, a pulling force is applied to the traction rope, causing the traction rope to move around the guide wheel. When the traction rope moves, a pulling force is applied to the iron core, causing the iron core to move in the sleeve along the axis of the sleeve. When the iron core moves, the mutual inductance between the secondary coil and the primary coil changes, causing the output current to fluctuate, and the displacement change can be accurately measured based on the output current. Among them, the present application uses the traction rope and the guide member to pull the iron core to move, and the sleeve is used to limit the iron core, so that the iron core can move linearly, thereby reducing the influence of the lever swing on the movement direction of the iron core and improving the measurement accuracy of the sensor.

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1It is a schematic diagram of the differential displacement sensor provided by the embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of the bottom plate and the annular side plate in the embodiment of the present invention;

[0028] Figure 3 It is an exploded view of the differential displacement sensor in the embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of the support assembly, the detection assembly and the traction assembly in the embodiment of the present invention;

[0030] Figure 5 It is a schematic diagram of the lever assembly in the embodiment of the present invention;

[0031] Figure 6 It is a cross-sectional view of the differential displacement sensor in the embodiment of the present invention.

[0032] Reference numerals: 1 - housing, 2 - support assembly, 201 - retaining piece, 202 - first spring, 203 - sleeve, 204 - support member, 3 - traction assembly, 301 - traction rope, 302 - guide wheel, 303 - support column, 4 - lever assembly, 401 - second spring, 402 - hinge hole, 403 - hinge shaft, 404 - probe, 405 - connecting sleeve, 5 - detection assembly, 501 - secondary coil, 502 - primary coil, 503 - iron core, 6 - cover plate, 7 - insertion rod, 8 - support column, 9 - insertion slot. Detailed implementation manners

[0033] The following further describes the present invention in detail with reference to specific embodiments, but the implementation manners of the present invention are not limited thereto.

[0034] Based on this, please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 and Figure 6, an embodiment of the present invention provides a differential displacement sensor, including a housing 1, a support assembly 2, a detection assembly 5, a traction assembly 3 and a lever assembly 4 are arranged in the housing 1; the support assembly 2 includes a sleeve 203, and the sleeve 203 is fixedly connected to the housing 1; the detection assembly 5 includes a secondary coil 501, a primary coil 502 and an iron core 503, the iron core 503 is inserted into the sleeve 203, and the iron core 503 is slidably connected to the sleeve 203, both the secondary coil 501 and the primary coil 502 are sleeved outside the sleeve 203, there are two secondary coils 501, and the two secondary coils 501 are respectively arranged on both sides of the primary coil 502; the lever assembly 4 includes a probe 404 and a hinge shaft 403, the hinge shaft 403 is fixedly connected to the housing 1, a hinge hole 402 is provided on the probe 404, the hinge shaft 403 is inserted into the hinge hole 402, one end of the probe 404 is located inside the housing 1, and the other end extends outside the housing 1; the traction assembly 3 includes a traction rope 301 and a guiding member, the guiding member includes a guiding wheel 302 and a support column 303, the support column 303 is fixedly connected to the housing 1, the guiding wheel 302 is rotatably connected to the support column 303, the guiding wheel 302 is oppositely arranged with the open end of the sleeve 203, the traction rope 301 is wound around the outer peripheral surface of the guiding wheel 302, and one end of the traction rope 301 is connected to the iron core 503, and the other end is connected to the probe 404.

[0035] In some embodiments of the present application, the differential displacement sensor is a lever-type LVDT sensor.

[0036] In some embodiments of the present application, the sleeve 203 is an insulating sleeve 203.

[0037] In some embodiments of the present application, the two secondary coils 501 are symmetrically arranged on both sides of the primary coil 502, wherein the primary coil 502 is used to generate an electromagnetic field, and the secondary coil 501 is used to receive the magnetic field change generated by the primary coil 502.

[0038] In some embodiments of the present application, the first end of the probe 404 extends outside the housing 1, the second end is located inside the housing 1, and the distance between the first end and the hinge hole 402 is less than the distance between the second end and the hinge hole 402.

[0039] In some embodiments of the present application, the hinge shaft 403 is inserted into the hinge hole 402 and the hinge shaft 403 and the hinge hole 402 are in clearance fit, so that the probe 404 can rotate relative to the hinge shaft 403.

[0040] In some embodiments of the present application, a bearing is sleeved between the guiding wheel 302 and the support column 303, the inner ring of the bearing is in interference fit with the support column 303, and the outer ring of the bearing is in interference fit with the central hole of the guiding wheel 302.

[0041] In some embodiments of the present application, when the differential sensor is in use, the first end of the probe rod 404 abuts against the measured object, so that the surface of the probe contacts the measured object. When one side of the probe is stressed, the probe rod 404 deflects around the hinge axis 403. At this time, the second end of the probe rod 404 moves in an arc towards the direction of the guide wheel 302. When the second end of the probe rod 404 moves, it applies a tensile force to the traction rope 301, causing the traction rope 301 to pull the iron core 503 to move smoothly in a linear motion manner. As the iron core 503 moves, the mutual inductance between the secondary coil 501 and the primary coil 502 changes, and this change will ultimately lead to fluctuations in the output current, thereby accurately measuring the change in displacement.

[0042] In the above solution of the present application, the differential displacement sensor includes a housing 1. Inside the housing 1, there are provided a support assembly 2, a detection assembly 5, a traction assembly 3, and a lever assembly 4. The support assembly 2 includes a sleeve 203, and the sleeve 203 is fixedly connected to the housing 1. The detection assembly 5 includes a secondary coil 501, a primary coil 502, and an iron core 503. The iron core 503 is inserted into the sleeve 203, and the iron core 503 is slidably connected to the sleeve 203. Both the secondary coil 501 and the primary coil 502 are sleeved outside the sleeve 203. There are two secondary coils 501, and the two secondary coils 501 are respectively arranged on both sides of the primary coil 502. The lever assembly 4 includes a probe rod 404 and a hinge axis 403. The hinge axis 403 is fixedly connected to the housing 1. There is a hinge hole 402 on the probe rod 404, and the hinge axis 403 is inserted into the hinge hole 402. One end of the probe rod 404 is inside the housing 1, and the other end extends outside the housing 1. The traction assembly 3 includes a traction rope 301 and a guide member. The guide member includes a guide wheel 302 and a support column 303. The support column 303 is fixedly connected to the housing 1. The guide wheel 302 is rotatably connected to the support column 303. The guide wheel 302 is arranged opposite to the open end of the sleeve 203. The traction rope 301 is wound around the outer peripheral surface of the guide wheel 302. One end of the traction rope 301 is connected to the iron core 503, and the other end is connected to the probe rod 404. With this structure, when the lever swings, it applies a tensile force to the traction rope 301, causing the traction rope 301 to move around the guide wheel 302. When the traction rope 301 moves, it applies a tensile force to the iron core 503, causing the iron core 503 to move inside the sleeve 203 along the axis of the sleeve 203. When the iron core 503 moves, the mutual inductance between the secondary coil 501 and the primary coil 502 changes, causing the output current to fluctuate. According to the output current, the change in displacement can be accurately measured. Among them, in the present application, the iron core 503 is pulled to move through the traction rope 301 and the guide member, and the iron core 503 is limited by the sleeve 203, so that the iron core 503 can perform linear motion, thereby reducing the influence of the lever swing on the movement direction of the iron core 503 and improving the measurement accuracy of the sensor.

[0043] It can be understood that in the present application, the probe rod 404 is pulled by the towing rope 301 and the guide pulley 302. By converting the deflection amount received by the probe rod 404 into the linear movement amount of the iron core 503, the direct influence of the deflection amount of the probe rod 404 on the iron core 503 can be avoided, so that the iron core 503 in the present application can perform linear movement, making the magnetic field change uniformly, and further making the induced voltage of the iron core 503 at different positions change according to a linear law, thereby improving the measurement accuracy of the sensor.

[0044] In some embodiments of the present application, such as Figure 3 , Figure 4 and Figure 6 shown, the support assembly 2 further includes a retaining piece 201 and a first spring 202. The retaining piece 201 is connected to the end of the iron core 503 away from the towing rope 301. The retaining piece 201 and the end face of the sleeve 203 are in limit fit, and the first spring 202 is arranged between the retaining piece 201 and the sleeve 203. With this structure, first, through the limit fit between the end face of the retaining piece 201 and the sleeve 203, the movement of the iron core 503 away from the sleeve 203 can be avoided, improving the reliability of the installation of the iron core 503. Second, by limiting the first spring 202 with the retaining piece 201, the separation of the first spring 202 from the iron core 503 can be avoided, improving the reliability of the installation of the first spring 202.

[0045] In some embodiments of the present application, the iron core 503 is of a cylindrical structure, the retaining piece 201 is a circular piece, the axis of the circular piece and the axis of the iron core 503 are on the same straight line, the diameter of the circular piece is greater than the diameter of the iron core 503, and the diameter of the circular piece is greater than the outer diameter of the first spring 202, and the outer diameter of the first spring 202 is greater than the inner diameter of the sleeve 203. In this way, one end of the first spring 202 is in limit fit with the retaining piece 201, and the other end is in limit fit with the end face of the sleeve 203.

[0046] In some embodiments of the present application, such as Figure 2 , Figure 3 and Figure 6 shown, the housing 1 includes a bottom plate and an annular side plate. The annular side plate is connected to the upper surface of the bottom plate, and the bottom plate and the annular side plate jointly enclose a receiving groove; the annular side plate includes a front plate, a rear plate, a first inclined plate, a second inclined plate, a first side plate and a second side plate. The length of the front plate is less than the length of the rear plate and the two are arranged in parallel. The projection of the front plate on the rear plate is located in the middle of the rear plate. The first inclined plate and the second inclined plate are respectively connected to both sides of the front plate, the first side plate and the second side plate are respectively connected to both sides of the rear plate, the first inclined plate is connected to the first side plate, and the second inclined plate is connected to the second side plate; a through hole is provided on the front plate, one end of the probe rod 404 is located in the receiving groove, and the other end passes through the through hole and extends out. With this structure, by optimizing the structure of the housing 1, the overall size of the sensor can be reduced, and the overall stability of the sensor can be improved.

[0047] In some embodiments of the present application, the first side plate and the second side plate are parallel to each other, and the angle between the first inclined plate and the first side plate is equal to the angle between the second inclined plate and the second side plate.

[0048] In some embodiments of the present application, as Figure 3 and Figure 5 shown, the lever assembly 4 further includes a second spring 401. One end of the second spring 401 is connected to the probe rod 404, and the other end is connected to the inner wall of the annular side plate. With this structure, the probe rod 404 and the annular side plate are connected by the second spring 401, which can improve the stability of the probe rod 404. Moreover, after the probe rod 404 swings, the second spring 401 can generate an elastic acting force to drive the probe rod 404 to reset, ensuring that the probe rod 404 can be reset to the initial position.

[0049] In some embodiments of the present application, when the measured object moves and applies pressure to the probe rod 404, the probe rod 404 can swing against the elastic action of the second spring 401. When the measured object separates from the probe rod 404, the second spring 401 applies an elastic force to the probe rod 404 to make the probe rod 404 reset to the initial position.

[0050] In some embodiments of the present application, the acting force of the second spring 401 is greater than that of the first spring 202, and the end of the probe rod 404 extending out of the housing 1 is fixedly connected with a probe for contacting the measured object.

[0051] In some embodiments of the present application, as Figure 1 , Figure 2 and Figure 3 shown, a connecting sleeve 405 is provided on the outer surface of the front plate. The axis of the connecting sleeve 405 is collinear with the axis of the perforation, and both ends of the hinge shaft 403 are fixedly connected to the inner wall of the connecting sleeve 405. The axis direction of the hinge shaft 403 is perpendicular to the axis direction of the connecting sleeve 405. With this structure, the probe rod 404 can be limited and protected by the connecting sleeve 405, which can improve the reliability of the probe rod 404.

[0052] In some embodiments of the present application, the connecting sleeve 405 is of an open-loop structure.

[0053] In some embodiments of the present application, as Figure 3 shown, an annular groove is provided on the outer peripheral surface of the guide wheel 302, and the traction rope 301 is embedded in the annular groove. The axis of the sleeve 203 is tangent to the guide wheel 302. With this structure, the traction rope 301 can be limited by the annular groove, which can improve the installation stability of the traction rope 301. When the axis of the sleeve 203 is tangent to the guide wheel 302, it can ensure that the traction rope 301 drives the iron core 503 to move linearly along the axial direction of the sleeve 203.

[0054] In some embodiments of the present application, there are two guiding members. The two guiding members are arranged in sequence in a direction perpendicular to the axial direction of the sleeve 203. The towing rope 301 is wound around the outer circumferences of the guide wheels 302 in both guiding members at the same time. With this structure, by guiding and limiting the towing rope 301 through the two guiding members, the stability of the movement of the towing rope 301 can be improved.

[0055] In some embodiments of the present application, there are also two supporting members 204 between the sleeve 203 and the bottom plate. The supporting members 204 are fixedly connected to the bottom plate, and the sleeve 203 is fixedly connected to the supporting members 204. The two supporting members 204 are symmetrically arranged at both ends of the sleeve 203 along the axial direction of the sleeve 203. With this structure, by supporting the sleeve 203 through the two supporting members 204, the stability of the sleeve 203 can be improved.

[0056] In some embodiments of the present application, the two supporting members 204 have the same shape and size.

[0057] In some embodiments of the present application, the housing 1 further includes a cover plate 6 and a plugging rod 7. The plugging rod 7 is fixedly connected to the lower surface of the cover plate 6. There is a supporting column 8 on the inner wall of the annular side plate. The bottom end of the supporting column 8 is fixedly connected to the bottom plate. There is a plugging groove 9 in the supporting column 8, and the plugging rod 7 and the plugging groove 9 are in plug-in fit. With this structure, by the plug-in fit of the plugging rod 7 and the plugging groove 9, the reliability of the connection between the cover plate 6 and the annular side plate can be improved, and thus the reliability of the overall sensor can be improved.

[0058] In some embodiments of the present application, there are four supporting columns 8; among them, there is a supporting column 8 at the connection between the first inclined plate and the first side plate, there is a supporting column 8 at the connection between the second inclined plate and the second side plate, there is a supporting column 8 at the connection between the first side plate and the rear plate, and there is a supporting column 8 at the connection between the second side plate and the rear plate; there are four plugging rods 7, and the four plugging rods 7 correspond to the four plugging grooves 9 respectively. With this structure, both the reliability of the overall annular side plate and the reliability of the connection between the cover plate 6 and the annular side plate can be improved, thereby improving the reliability of the overall sensor.

[0059] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is 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 construed as a limitation to the present invention.

[0060] In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", and "third" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0061] In the present invention, unless otherwise clearly specified and defined, terms such as "mounted", "connected", "coupled", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0062] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely means that the horizontal height of the first feature is lower than that of the second feature.

[0063] The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. A differential displacement sensor, characterized in that: It comprises a housing, in which a supporting assembly, a detecting assembly, a traction assembly and a lever assembly are arranged; The support assembly includes a sleeve, and the sleeve is fixedly connected to the housing; The detection assembly includes a secondary coil, a primary coil and an iron core, the iron core is inserted into the sleeve, and the iron core and the sleeve are slidably connected, the secondary coil and the primary coil are both sleeved outside the sleeve, two secondary coils are provided, and the two secondary coils are respectively arranged on both sides of the primary coil; The lever assembly includes a probe rod and a hinge shaft, the hinge shaft is fixedly connected to the housing, a hinge hole is provided on the probe rod, the hinge shaft is inserted into the hinge hole, one end of the probe rod is located in the housing, and the other end extends out of the housing; The traction assembly includes a traction rope and a guide member, the guide member includes a guide wheel and a pillar, the pillar and the shell are fixedly connected, the guide wheel and the pillar are rotatably connected, the guide wheel and the open end of the sleeve are arranged opposite to each other, the traction rope is wound around the outer peripheral surface of the guide wheel, and one end of the traction rope is connected to the iron core, and the other end is connected to the probe rod.

2. The differential displacement sensor according to claim 1, characterized in that: The support assembly also includes a baffle and a first spring. The baffle is connected to one end of the iron core away from the traction rope. The baffle and the end surface of the sleeve are limitedly matched. The first spring is arranged between the baffle and the sleeve.

3. The differential displacement sensor according to claim 1, characterized in that: The housing comprises a bottom plate and an annular side plate, wherein the annular side plate is connected to the upper surface of the bottom plate, and the bottom plate and the annular side plate together form a receiving groove; The annular side plate comprises a front plate, a rear plate, a first inclined plate, a second inclined plate, a first side plate and a second side plate, the length of the front plate is smaller than that of the rear plate and the two are arranged in parallel, the projection of the front plate on the rear plate is located in the middle of the rear plate, the first inclined plate and the second inclined plate are respectively connected to both sides of the front plate, the first side plate and the second side plate are respectively connected to both sides of the rear plate, the first inclined plate is connected to the first side plate, and the second inclined plate is connected to the second side plate; The front plate is provided with a through hole, one end of the probe rod is located in the accommodating groove, and the other end thereof extends out through the through hole.

4. The differential displacement sensor according to claim 3, characterized in that: The lever assembly also includes a second spring, one end of which is connected to the probe rod, and the other end of which is connected to the inner wall of the annular side plate.

5. The differential displacement sensor according to claim 3, characterized in that: A connecting sleeve is provided on the outer surface of the front plate, the axis of the connecting sleeve and the axis of the through hole are collinear, both ends of the hinge shaft are fixedly connected to the inner wall of the connecting sleeve, and the axial direction of the hinge shaft is perpendicular to the axial direction of the connecting sleeve.

6. The differential displacement sensor according to claim 1, characterized in that: An annular groove is arranged on the outer peripheral surface of the guide wheel, the traction rope is embedded in the annular groove, and the axis of the sleeve is tangent to the guide wheel.

7. The differential displacement sensor according to claim 1, characterized in that: There are two guide members, which are arranged in sequence along a direction perpendicular to the axial direction of the sleeve, and the traction rope is simultaneously wound around the outer periphery of the guide wheels in the two guide members.

8. The differential displacement sensor according to claim 3, characterized in that: Two supporting members are also provided between the sleeve and the base plate. The supporting members are fixedly connected to the base plate, and the sleeve is fixedly connected to the supporting members. The two supporting members are symmetrically arranged at both ends of the sleeve along the axial direction of the sleeve.

9. The differential displacement sensor according to claim 3, characterized in that: The shell also includes a cover plate and a plug-in rod, the plug-in rod is fixedly connected to the lower surface of the cover plate, a support column is provided on the inner wall of the annular side plate, the bottom end of the support column is fixedly connected to the bottom plate, a plug-in slot is provided in the support column, and the plug-in rod and the plug-in slot are plug-fitted.

10. The differential displacement sensor according to claim 9, characterized in that: There are four support columns; Wherein, a support column is provided at the connection between the first inclined plate and the first side plate, a support column is provided at the connection between the second inclined plate and the second side plate, a support column is provided at the connection between the first side plate and the rear plate, and a support column is provided at the connection between the second side plate and the rear plate; There are four plug-in rods, and the four plug-in rods correspond to the four plug-in slots respectively.

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