Magnetostrictive displacement sensor

Abstract

The invention discloses a magnetostrictive displacement sensor, which relates to the technical field of electronic measuring tools and comprises a measuring head, a measuring rod and a vernier, the measuring head and the measuring rod are connected with each other, and the vernier is arranged on the measuring rod and can move along the length direction of the measuring rod. The measuring head comprises a shell, a sensitive element assembly, a signal processing element, a pulse element and a tail cover assembly, the tail cover assembly is detachably arranged on the side, opposite to the measuring rod, of the shell, the sensitive element assembly, the signal processing element and the pulse element are installed in the shell through a support, and the signal processing element and the pulse element abut against the inner side wall of the shell in a buffering mode; in the technical scheme provided by the invention, the signal processing element and the pulse element respectively abut against the inner side wall of the shell in a buffering manner, so that when the shell of the measuring head bears a relatively large impact force, the impact force can be absorbed through the buffering structure, and the signal processing element and the pulse element are not easy to damage.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic measuring tools, and particularly to a magnetostrictive displacement sensor. Background Art

[0002] A magnetostrictive displacement sensor is a displacement sensor for high-precision and long-stroke absolute position measurement manufactured based on the magnetostrictive principle. It generally consists of a probe containing a sensitive element assembly (i.e., a magnetostrictive waveguide wire loop), a measuring rod, and a cursor magnetic ring movably installed on the measuring rod. The detection mechanism of the magnetostrictive linear displacement sensor is based on the Wiedemann effect between the magnetostrictive waveguide wire loop, the core detection element of the sensor, and the cursor magnetic ring, that is, some magnetic materials will undergo small dimensional changes when subjected to a magnetic field.

[0003] The waveguide wire is arranged along the length direction of the measuring rod. When a current pulse passes through the waveguide wire, an annular magnetic field will be generated around the waveguide wire. The cursor magnetic ring (usually connected to the object to be measured) is located on the measuring rod. When the magnetic ring moves, its magnetic field interacts with the magnetic field of the waveguide wire, causing the waveguide wire to generate a torsional stress wave. This stress wave propagates along the waveguide wire, and its propagation speed is known and constant. The sensor calculates the position of the magnetic ring by measuring the time difference between the pulse current and the detected stress wave, thereby accurately measuring the displacement.

[0004] For an in-built magnetostrictive displacement sensor, when it is in use, it is installed inside the oil cylinder and is a device for accurately measuring the telescopic displacement of the oil cylinder. The working environment is relatively harsh, and it is prone to vibration and impact, and the components inside the magnetostrictive displacement sensor are easily damaged accordingly. Summary of the Invention

[0005] The main object of the present invention is to propose a magnetostrictive displacement sensor, aiming to provide a magnetostrictive displacement sensor with better seismic performance.

[0006] To achieve the above object, the magnetostrictive displacement sensor proposed by the present invention includes a probe and a measuring rod connected to each other, and a cursor provided on the measuring rod and movable along the length direction of the measuring rod; Wherein, the probe includes a housing, a sensitive element assembly, a signal processing element, a pulse element, and a tail cover assembly. The tail cover assembly is detachably provided on the side of the housing facing away from the measuring rod. The tail cover assembly and the housing jointly enclose a containing cavity. The sensitive element assembly, the signal processing element, and the pulse element are all provided in the containing cavity, and the sensitive element assembly is electrically connected to the signal processing element and the pulse element respectively. A waveguide wire is provided inside the measuring rod, and one end of the waveguide wire is connected to the sensitive element assembly; The magnetostrictive displacement sensor further includes a bracket, which includes a first enclosing plate and a second enclosing plate. One of the first enclosing plate and the second enclosing plate is provided with a plug-in portion, and the other is provided with a mating portion. The plug-in portion is snap-fitted and limited in the mating portion. The first enclosing plate and the second enclosing plate enclose to form a limiting groove, and at least part of the structure of the sensitive element assembly is limited in the limiting groove. The signal processing element and the pulse element are respectively arranged on opposite sides of the sensitive element assembly, and both the signal processing element and the pulse element are in buffered contact with the inner side wall of the housing.

[0007] In one embodiment, the outer peripheries of the signal processing element and the pulse element are coated with a flexible buffer structure, and the inner wall of the housing is provided with an abutting groove, and the flexible buffer structure abuts against the abutting groove.

[0008] In one embodiment, a plurality of first fixing holes and a plurality of second fixing holes are respectively provided on opposite sides of the first enclosing plate and the second enclosing plate, and the signal board and the pulse board are respectively fixed to the plurality of first fixing holes and the plurality of second fixing holes; There is a heat dissipation air duct formed between both the signal processing element and the pulse element and the bracket.

[0009] In one embodiment, the sensitive element assembly includes a base, a shielding cover installed on one side of the base, and a sensitive element board. The base and the shielding cover enclose to form a shielding cavity, and the sensitive element board is arranged in the shielding cavity; a glass fiber tube is provided on the other side of the base, and a high-temperature wire and the waveguide wire are arranged in the glass fiber tube, and the glass fiber tube extends along the length direction of the measuring rod.

[0010] In one embodiment, third fixing holes are provided at one ends of the first enclosing plate and the second enclosing plate facing the end cover assembly, and the end cover assembly is fixed to the first enclosing plate and the second enclosing plate through the third fixing holes.

[0011] In one embodiment, base fixing grooves are provided on the sides of the first enclosing plate and the second enclosing plate facing the limiting groove, and the base is snap-fitted and limited in the base fixing grooves.

[0012] In one embodiment, the end cover assembly includes an end cover plate and a first bolt, and the end cover plate is screwed to the housing through the first bolt; and / or The end cover assembly includes an end cover plate, the end cover plate is provided with a clamping convex, and the housing is provided with a clamping groove, and the clamping convex is clamped in the clamping groove.

[0013] In one embodiment, the housing includes a front housing and a rear housing. Two ends of the rear housing are respectively connected to the front housing and the tail cover plate. The first bolt sequentially passes through the tail cover plate and the rear housing and is screwed and fixed to the front housing.

[0014] In one embodiment, the tail cover assembly further includes a power board. The power board is disposed on a side of the tail cover plate facing the sensitive element assembly and is located in the accommodating cavity. The power board is provided with a connector. The signal processing element is electrically connected to the power board through the connector. On a side of the tail cover plate facing away from the power board, there is at least one connector. One end of at least one connector is electrically connected to the power board. The connector is used for externally connecting a signal source. The front housing is provided with a connection hole communicating the accommodating cavity and the measuring rod. On a side of the front housing facing away from the rear housing, there is a mounting portion.

[0015] In one embodiment, the magnetostrictive displacement sensor further includes a mounting base. The mounting base is disposed at an end of the housing close to the measuring rod and is located in the accommodating cavity. The mounting base is detachably disposed on the housing.

[0016] The technical solution of the present invention installs the entire probe on the outside of the device to be measured, and enables each electrical component inside the probe to be detachable relative to the device to be measured, thereby greatly facilitating the maintenance work of the displacement sensor and enabling the signal processing element and the pulse element to be respectively buffer - abutted against the inner side wall of the housing, thereby improving the overall seismic performance of the device. Specifically, the magnetostrictive displacement sensor is mainly divided into three parts: a probe, a measuring rod, and a cursor. The probe is installed at the fixed end of the device to be measured. One end of the measuring rod is connected to the probe. The cursor is movably sleeved on the measuring rod and moves in the same motion as the free end. When the free end moves relative to the fixed end, the cursor will also move on the measuring rod accordingly to generate a pulse current to achieve distance measurement. The probe mainly includes a housing, a sensitive element assembly, a signal processing element, a pulse element, and a tail cover assembly. The sensitive element assembly, the signal processing element, and the pulse element are all installed inside the housing through brackets. The signal processing element and the pulse element are respectively installed on both sides of the bracket, and the sensitive element assembly is installed between them. The signal processing element and the pulse element are respectively buffer - abutted against the inner side wall of the housing, so that when the housing of the probe bears a large impact force, it can be absorbed through the buffer structure, thereby ensuring that the signal processing element and the pulse element are not easily damaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0018] Figure 1 Schematic structural diagram of an embodiment of the magnetostrictive displacement sensor provided by the present invention; Figure 2 For Figure 1 Schematic structural diagram of the magnetostrictive displacement sensor from another angle; Figure 3 For Figure 1 Cross-sectional view of the magnetostrictive displacement sensor; Figure 4 Schematic assembly diagram of the sensitive element assembly and the bracket; Figure 5 For Figure 1 Schematic structural diagram of the bracket; Figure 6 For Figure 5 Schematic structural diagram of the disassembled bracket; Figure 7 Schematic position and structure diagram of each component inside the magnetostrictive displacement sensor; Figure 8 Schematic structural diagram of each component inside the magnetostrictive displacement sensor from another angle; Figure 9 Schematic structural diagram of the sensitive element assembly; Figure 10 Schematic structural diagram of the measuring rod; Figure 11 Schematic structural diagram of the mounting base; Figure 12 Schematic structural diagram of the rear shell; Figure 13 Schematic structural diagram of the first embodiment of the tail cap assembly; Figure 14 For Figure 13 Schematic structural diagram of the tail cap assembly from another angle; Figure 15 Schematic structural diagram of the second embodiment of the tail cap assembly; Figure 16 Schematic structural diagram of the third embodiment of the tail cap assembly; Figure 17 Schematic structural diagram of the fourth embodiment of the tail cap assembly; Figure 18 Schematic structural diagram of the fifth embodiment of the tail cap assembly; Figure 19 Exploded structural schematic diagram of an embodiment of the magnetostrictive displacement sensor provided by the present invention; Figure 20 is Figure 19 structural schematic diagram of the flexible buffer structure in; Figure 21 Structural schematic diagram of another embodiment of the magnetostrictive displacement sensor provided by the present invention.

[0019] Explanation of the reference numerals in the drawings: 100, magnetostrictive displacement sensor; 1, probe head; 11, housing; 11a, accommodating cavity; 111, front shell; 1111, screwing part; 1112, sealing ring; 1113, connecting part; 112, rear shell; 1121, abutting groove; 113, mounting seat; 1131, clamping seat; 114, clamping groove; 12, sensitive element assembly; 121, base; 122, shielding cover; 123, sensitive element board; 124, shielding tube; 125, glass fiber tube; 126, high-temperature wire; 127, waveguide wire; 128, flexible circuit board socket; 13, signal processing element; 14, pulse element; 15, end cap assembly; 151, end cap plate; 1511, connector; 1512, indicator light; 1513, clamping projection; 152, first bolt; 153, power supply board; 1531, connector; 16, bracket; 16a, sensitive element accommodating cavity; 16b, heat dissipation air duct; 161, first enclosure; 162, second enclosure; 163, second fixing hole; 164, first fixing hole; 165, third fixing hole; 166, second bolt; 167, clamping projection; 168, pin hole; 169, pin; 17, flexible buffer structure; 2, measuring rod; 3, cursor; 4, slider; 41, connecting piece; 5, guide rail; 200, cable.

[0020] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0023] In addition, if the embodiments of the present invention involve descriptions such as "first" and "second", the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel scenarios. Taking "A and / or B" as an example, it includes Scenario A, or Scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0024] Regarding the built-in magnetostrictive displacement sensor 100, it is installed inside the oil cylinder during use and is a device for precisely measuring the telescopic displacement of the oil cylinder. The working environment is relatively harsh and it is easily affected by vibration and impact, and the components inside the magnetostrictive displacement sensor 100 are easily damaged accordingly.

[0025] To solve the above problems, the present invention proposes a magnetostrictive displacement sensor 100, aiming to provide a magnetostrictive displacement sensor 100 with better seismic performance. Figures 1 to 16 It is a schematic structural diagram of an embodiment provided for the magnetostrictive displacement sensor 100 of the present invention.

[0026] Please refer to Figures 1 to 18, the present invention provides a magnetostrictive displacement sensor 100, which includes a probe head 1 and a measuring rod 2 connected to each other, and a cursor 3 provided on the measuring rod 2 and movable along the length direction of the measuring rod 2; wherein, the probe head 1 includes a housing 11, a sensitive element assembly 12, a signal processing element 13, a pulse element 14 and a tail cover assembly 15. The tail cover assembly 15 is detachably provided on the side of the housing 11 facing away from the measuring rod 2. The tail cover assembly 15 and the housing 11 together enclose a containing cavity 11a. The sensitive element assembly 12, the signal processing element 13 and the pulse element 14 are all provided in the containing cavity 11a, and the sensitive element assembly 12 is electrically connected to the signal processing element 13 and the pulse element 14 respectively. A waveguide wire 127 is provided inside the measuring rod 2, and one end of the waveguide wire 127 is connected to the sensitive element assembly 12; the magnetostrictive displacement sensor 100 further includes a bracket 16, the bracket 16 includes a first enclosing plate 161 and a second enclosing plate 162. One of the first enclosing plate 161 and the second enclosing plate 162 is provided with a plugging part, and the other is provided with a matching part. The plugging part is clamped and limited in the matching part. The first enclosing plate 161 and the second enclosing plate 162 enclose a limiting groove, at least part of the structure of the sensitive element assembly 12 is limited in the limiting groove, the signal processing element 13 and the pulse element 14 are respectively provided on opposite sides of the sensitive element assembly 12, and both the signal processing element 13 and the pulse element 14 are in buffered contact with the inner side wall of the housing 11.

[0027] The magnetostrictive displacement sensor 100 has a high-precision measurement effect. Its working principle is based on the magnetostrictive effect, that is, when a ferromagnetic material is under the action of an external magnetic field, its size will elongate or shorten, and after removing the external magnetic field, it will return to its original length. The basic principle of this sensor is to utilize the magnetostrictive effect to accurately sense displacement by measuring the length change of the material under the action of the magnetic field. In a specific implementation, the sensor includes a probe 1 and a measuring rod 2 connected to each other, and a cursor 3 disposed on the measuring rod 2 and movable along the length direction of the measuring rod 2. The signal processing element 13 and the pulse element 14 in the magnetostrictive displacement sensor 100 are key components for realizing the ranging function. The signal processing element 13 is responsible for processing the signals generated by the sensitive element assembly 12, while the pulse element 14 is responsible for generating and controlling the pulse signals. During the measurement process, a current pulse is generated in the electronic chamber of the sensor, and this current pulse is transmitted in the waveguide wire 127, thereby generating a circumferential magnetic field outside the waveguide wire 127. When this magnetic field intersects with the magnetic field generated by the movable magnetic ring sleeved on the waveguide wire 127 as the position changes, due to the magnetostrictive effect, a strain mechanical wave pulse signal will be generated in the waveguide wire 127. This strain mechanical wave pulse signal is transmitted at a fixed sound speed and is quickly detected by the electronic chamber. Since the transmission time of the strain mechanical wave pulse signal in the waveguide wire 127 is proportional to the distance between the movable magnetic ring and the electronic chamber, by measuring the time, this distance can be determined with high precision. In this way, the magnetostrictive displacement sensor 100 can accurately measure the displacement of equipment such as oil cylinders, thereby realizing the real-time monitoring and control of the equipment position.

[0028] It should be noted that the signal processing element 13 and the pulse element 14 being buffer-abutted against the inner side wall of the housing 11 can be achieved by configuring the outer peripheries of the signal processing element 13 and the pulse element 14 as flexible materials, or by sleeving flexible buffer strips around the signal processing element 13 and the pulse element 14. The present invention does not limit this. In an embodiment of the present invention, the outer peripheries of the signal processing element 13 and the pulse element 14 are coated with a flexible buffer structure 17. Specifically, please further refer to Figure 3 、 Figure 17 、 Figure 18 、 Figure 19 and Figure 20, an abutting groove 1121 is provided on the inner wall of the housing 11, and the flexible buffer structure 17 abuts against the abutting groove 1121. When the magnetostrictive displacement sensor 100 is installed on an oil cylinder of large machinery, a lifting device, or a construction machinery, the vibration or impact generated by the operation of the measured device will inevitably be transmitted to the probe 1. The probe 1, the housing 11, the internal signal processing element 13, and the pulse element 14 are soft-connected, so as to reduce the direct acting force on the signal processing element 13 and the pulse element 14, thereby protecting these elements from damage and extending the service life of the sensor. Secondly, the soft connection achieved through flexible materials or buffer strips can reduce the noise and errors caused by mechanical vibration, improving the measurement accuracy and reliability. In addition, this design also helps to maintain the integrity of the sensor structure, ensuring that it can still operate stably under harsh working conditions. Generally speaking, this flexible buffer structure 17 provides necessary protection for the sensor, enhances its anti-vibration and anti-impact capabilities, and makes it more suitable for high-demand industrial application environments.

[0029] The technical solution of the present invention installs the probe 1 as a whole on the outside of the device to be measured, and enables the electrical components inside the probe 1 to be disassembled relative to the device to be measured, thus greatly facilitating the maintenance work of the displacement sensor and making the signal processing element 13 and the pulse element 14 buffer and abut against the inner side wall of the housing 11 respectively, thereby improving the overall seismic performance of the device. Specifically, the magnetostrictive displacement sensor 100 mainly consists of three parts: a probe 1, a measuring rod 2, and a cursor 3. The probe 1 is installed at the fixed end of the device to be measured. One end of the measuring rod 2 is connected to the probe 1. The cursor 3 is movably sleeved on the measuring rod 2 and moves in the same motion as the free end. When the free end moves relative to the fixed end, the cursor 3 will also move on the measuring rod 2 to generate a pulsed current to achieve distance measurement. The probe 1 mainly includes a housing 11, a sensitive element assembly 12, a signal processing element 13, a pulse element 14, and a tail cover assembly 15. The sensitive element assembly 12, the signal processing element 13, and the pulse element 14 are all installed inside the housing 11 through a bracket 16. The signal processing element 13 and the pulse element 14 are respectively installed on both sides of the bracket 16, and the sensitive element assembly 12 is installed between them. The signal processing element 13 and the pulse element 14 buffer and abut against the inner side wall of the housing 11 respectively. When the housing 11 of the probe 1 bears a large impact force, it can be absorbed through the buffer structure, ensuring that the signal processing element 13 and the pulse element 14 are not easily damaged.

[0030] In the technical solution of the present invention, both the first enclosure 161 and the second enclosure 162 are in a C shape, and the openings of the first enclosure 161 and the second enclosure 162 face each other. To realize the assembly of the first enclosure 161 and the second enclosure 162, a plug-in part is provided on one of the first enclosure 161 and the second enclosure 162, and a mating part is provided on the other. That is, when the plug-in part is provided on the first enclosure 161, the mating part is provided at the corresponding position of the second enclosure 162; when the plug-in part is provided on the second enclosure 162, the mating part is provided at the corresponding position of the first enclosure 161. Specifically, please further refer to Figure 5 and Figure 6 , Figure 5 which represents the structural schematic diagram of the completed state of the splicing of the first enclosure 161 and the second enclosure 162, Figure 6 and which represents the structural schematic diagram before the splicing of the first enclosure 161 and the second enclosure 162. It should be noted that the plug-in part and the mating part can be a pin 169 and a pin hole 168 respectively, or a snap and a slot respectively. The present invention does not limit this. In an embodiment of the present invention, the plug-in part is a pin 169, and the mating part is a pin hole 168. The pin 169 and the pin hole 168 are connected by an interference fit. The characteristics of the interference fit connection are simple structure, good centering, large load-bearing capacity, small weakening of the strength of the shaft and hole, and good impact resistance. This connection method can provide a high fitting accuracy, ensuring the accuracy and reliability of mechanical assembly. In addition, the interference connection reduces the number of parts, simplifies the mechanical structure, makes the connection firm, and has a good fastening degree.

[0031] To provide a stable installation for the sensitive element assembly 12 installed on the bracket 16, the first enclosure 161 and the second enclosure 162 jointly enclose to form a sensitive element accommodation cavity 16a, and a clamping protrusion 167 is provided on the inner side wall of the sensitive element accommodation cavity 16a. Specifically, please further refer to Figure 5 , and by clamping the clamping protrusion 167 with the base 121 of the sensitive element assembly 12, the fixation of the sensitive element assembly 12 can be realized. The bracket 16 and the sensitive element assembly 12 are closely matched in structure. One end of the bracket 16 is provided with a lead-out hole for leading out the shielding tube 124. The lead-out hole is formed by enclosing two half-grooves respectively provided on one side of the first enclosure 161 and the second enclosure 162. When the sensitive element assembly 12 is installed in the sensitive element accommodation cavity 16a, the shielding tube 124 is led out from the lead-out hole, so as to make the structural layout more reasonable. To further fix the sensitive element assembly 12, the second bolt 166 is screwed onto the bracket 16 and extends into the interior of the sensitive element accommodation cavity 16a. The end of the second bolt 166 abuts against the sensitive element assembly 12, thereby realizing the overall fixing effect of the sensitive element assembly 12.

[0032] In an embodiment of the present invention, both the signal processing element 13 and the pulse element 14 are mounted on the bracket 16 and are located on opposite sides of the bracket 16. Correspondingly, for mounting the signal processing element 13 and the pulse element 14, the first fixing hole 164 and the second fixing hole 163 are respectively formed on both sides of the bracket 16. Specifically, please further refer to Figure 4 , the signal processing element 13 and the pulse element 14 are respectively arranged in the first fixing hole 164 and the second fixing hole 163. To prevent the signal processing element 13 and the pulse element 14 from rotating relative to the bracket 16, the number of the first fixing holes 164 is two or more. In this embodiment, 4 first fixing holes 164 are arranged on one side of the bracket 16, and the 4 first fixing holes 164 are respectively arranged at positions close to the four corners of the bracket 16. By connecting the signal processing element 13 through the 4 first fixing holes 164, the reliability of its connection can be ensured, and the signal processing element 13 can also be prevented from rotating relative to the bracket 16. In addition, in the present invention, the 4 first fixing holes 164 are designed to be raised so that they protrude from the side surface of the bracket 16, so that there is a certain distance between the signal processing element 13 and the surface of the bracket 16, that is, the heat dissipation air duct 16b, which can avoid the heat accumulation generated by the operation of the signal processing element 13 and the sensitive element board 123 arranged in the bracket 16 and is difficult to dissipate heat. By designing the signal processing element 13 to be overhead, an air flow air duct can be formed, which is more beneficial to the heat dissipation of the signal processing element 13 and the sensitive element board 123 and avoids damage to the circuit board due to heat accumulation. Similarly, 4 second fixing holes 163 are also arranged and designed to be overhead, so that there is also a certain gap between the pulse element 14 and the bracket 16, that is, the heat dissipation air duct 16b, which is beneficial to heat dissipation.

[0033] The waveguide wire 127 in the magnetostrictive displacement sensor 100 is the core component of the sensor and plays a crucial role in the measurement process. The waveguide wire 127 is usually a thin wire with a diameter of only 0.5 mm - 0.80 mm. The Wiedemann effect between the waveguide wire 127 and the cursor 3 magnetic ring is the basis of the detection mechanism of the magnetostrictive displacement sensor 100. It can be seen that the main function of the waveguide wire 127 is to be used as a medium for signal transmission to realize displacement measurement. To realize signal conduction, the waveguide wire 127 and the high-temperature wire 126 are encapsulated in the glass fiber tube 125. The non-magnetic insulation property of the glass fiber tube 125 can block external electromagnetic interference, ensure the precise superposition of the pulse current in the waveguide wire 127 and the magnetic field of the magnetic ring to form a spiral magnetic field, and avoid signal distortion; its high-strength structure can resist mechanical shock, prevent the waveguide wire 127 from bending or wearing, and ensure the integrity of the ultrasonic signal; at the same time, the low thermal expansion coefficient of the glass fiber material combined with the temperature compensation algorithm can control the temperature drift error within ±0.01 mm. Further, a shielding tube 124 is sleeved outside the glass fiber tube 125. Specifically, please further refer to Figure 3, a shielding tube 124 is additionally provided outside the glass fiber tube 125, and an electromagnetic shielding layer is formed by a metal material (such as copper mesh or aluminum foil), which can efficiently absorb or reflect external electromagnetic interference, greatly improving the signal stability of the sensor in a strong electromagnetic environment; at the same time, the shielding tube 124 serves as an outer physical protection, capable of withstanding external mechanical impacts, friction, and corrosion by corrosive media (such as oil stains, acids, and alkalis), extending the service life of the glass fiber tube 125 and the internal waveguide wire 127, further enhancing the anti-interference ability, and ultimately achieving the dual goals of high-fidelity signal transmission and high-reliability operation of the device in complex industrial scenarios.

[0034] In an embodiment of the present invention, the sensitive element assembly 12 includes a base 121, a shielding cover 122 installed on one side of the base 121, and a sensitive element board 123. The sensitive element board 123 is installed between the brackets 16 and is located in the shielding cavity formed by the enclosure of the shielding cover 122 and the base 121. Specifically, please further refer to Figure 9 , a Faraday cage effect is formed through the shielding cover 122 (such as copper or aluminum), effectively blocking external electromagnetic interference (such as power frequency magnetic field, radio frequency radiation) and suppressing internal signal leakage, ensuring circuit stability; at the same time, the shielding cover 122 can withstand physical impacts, dust intrusion, and environmental corrosion, reducing circuit noise and improving the signal-to-noise ratio, especially avoiding self-excited oscillation in high-frequency or precision circuits, and achieving the best electromagnetic compatibility and device reliability in combination with grounding optimization (such as single-ended grounding) and material adaptation. A flexible circuit socket 128 is provided on the sensitive element board 123, and is electrically connected to the signal processing element 13 through the flexible circuit socket 128, thereby realizing the intercommunication of data signals.

[0035] When the traditional magnetostrictive displacement sensor 100 installed on the oil cylinder is maintained, the oil cylinder needs to be depressurized, and the process requires long-term shutdown, affecting production. Moreover, during the disassembly process of the displacement sensor, the disassembly and installation are difficult and the operation is very inconvenient. In view of this, the magnetostrictive displacement sensor 100 proposed by the present invention adopts a split design. The measuring rod 2 is integrally installed inside the oil cylinder. The front shell 111 is provided with a screwing part 1111 and is screwed and fixed to the oil cylinder body through the screwing part 1111. The measuring rod 2 and the front shell 111 are integrated into a part of the oil cylinder in structure. The rear shell 112 of the measuring head 1, the sensitive element assembly 12, the signal processing element 13, the pulse element 14, and the end cap assembly 15 are located outside the oil cylinder. When maintenance is required for some electronic components located in the inner cavity 11a of the housing 11, only the end cap assembly 15 needs to be disassembled, that is, the end cap assembly 15 is disassembled relative to the housing 11, and then the internal components can be exposed, so that maintenance can be realized without shutdown, thus not affecting the production progress.

[0036] Correspondingly, the end cap assembly 15 is provided with a first bolt 152. Specifically, please further refer to Figure 2, the first bolt 152 is configured as an elongated bolt, which passes through the rear shell 112, the mounting seat 113 and is fixed to the front shell 111. Through the first bolt 152, the tail cover assembly 15, the rear shell 112, the mounting seat 113 and the front shell 111 are fixedly connected together, simplifying the installation steps between the components and further facilitating disassembly and maintenance. In an embodiment of the present application, two first bolts 152 are provided in total. When the first bolts 152 are removed, the tail cover assembly 15 and the rear shell 112 can be sequentially removed so that the various electronic components installed in the accommodating cavity 11a are exposed to the outside. During this process, the measuring rod 2 installed on the oil cylinder body never needs to be disassembled, and the device does not need to stop running.

[0037] In an embodiment of the present invention, to fix the bracket 16, the mounting seat 113 is provided with a clamping seat 1131. Specifically, please further refer to Figure 11 , the clamping seat 1131 is connected to the bracket 16 that fixes the sensitive element assembly 12, the signal processing element 13 and the pulse element 14, so as to realize the support and fixation. To enable electrical energy to be input from the tail cover plate 151 to provide the electrical energy required for the device to operate, the tail cover assembly 15 includes a power board 153. Specifically, please further refer to Figure 3 and Figure 7 , the power board 153 is connected to the cable 200, and the power board 153 is provided with a connector 1531, which is connected to the signal processing element 13 through the connector 1531. To fix the power board 153, the bracket 16 is provided with a third fixing hole 165 on the side adjacent to the first fixing hole 164 and the second fixing hole 163. The power board 153 is installed on the bracket 16 through the third fixing hole 165. It can be seen that the sensitive element board 123, the signal processing element 13, the pulse element 14 and the power board 153 are all installed on the bracket 16, improving the overall integration of the device and being more conducive to disassembly.

[0038] In the technical solution of the present invention, different tail covers can be adaptively adjusted according to the needs of users, such as a single aviation tail cover. Specifically, please further refer to Figure 13 and Figure 14 , and also such as a double aviation tail cover. Specifically, please further refer to Figure 15 and Figure 16 , and also such as a triple aviation tail cover. Specifically, please further refer to Figure 17 and Figure 18。The single aviation tail cover has a simple structure and is suitable for scenarios with low requirements for signal transmission or limited space. It can meet the basic power and signal transmission requirements while reducing the installation space and cost. The double aviation tail cover provides more interface options and is suitable for complex systems that need to transmit multiple signals simultaneously (such as power, data, and control signals), enhancing the versatility and flexibility of the device. The triple aviation tail cover further expands the number of interfaces and is suitable for application scenarios of high-precision measurement and complex control. It can support the connection of multiple sensors or actuators simultaneously, ensuring the efficient operation of the system and the stability of data transmission.

[0039] In another embodiment of the present application, the magnetostrictive displacement sensor is an external sensor. Specifically, please further refer to Figure 21 , a guide rail 5 is provided at one end of the probe head 1 along the extension direction of the probe rod 2. The slider 4 is slidably arranged on the guide rail 5, and the magnetostrictive cursor 3 is built in the slider 4. The slider 4 moves along the direction of the guide rail 5, which can play a certain guiding role for the cursor 3. In addition, a connecting piece 41 is provided on the slider 4. One end of the connecting piece 41 has an external thread and can be connected to the device to be measured through the connecting piece 41. The external sensor can be applied to the measurement of external structures, further expanding the application scenarios of this solution.

[0040] The above are only exemplary embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformation made under the technical concept of the present invention by using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A magnetostrictive displacement sensor, characterized in that, It includes a connected probe (1) and a probe rod (2), and a cursor (3) provided on the probe rod (2) and movable along the length direction of the probe rod (2); Among them, the probe (1) includes a housing (11), a sensitive element assembly (12), a signal processing element (13), a pulse element (14), and a tail cover assembly (15). The tail cover assembly (15) is detachably provided on the side of the housing (11) facing away from the probe rod (2). The tail cover assembly (15) and the housing (11) jointly enclose a containing cavity (11a). The sensitive element assembly (12), the signal processing element (13), and the pulse element (14) are all arranged in the containing cavity (11a). And the sensitive element assembly (12) is electrically connected to the signal processing element (13) and the pulse element (14) respectively. A waveguide wire (127) is arranged inside the probe rod (2), and one end of the waveguide wire (127) is connected to the sensitive element assembly (12); The magnetostrictive displacement sensor (100) further includes a bracket (16). The bracket (16) includes a first enclosing plate (161) and a second enclosing plate (162). One of the first enclosing plate (161) and the second enclosing plate (162) is provided with a plugging part, and the other is provided with a matching part. The plugging part is clamped and limited in the matching part. The first enclosing plate (161) and the second enclosing plate (162) enclose a limiting groove. At least part of the structure of the sensitive element assembly (12) is limited in the limiting groove. The signal processing element (13) and the pulse element (14) are respectively arranged on opposite sides of the sensitive element assembly (12), and both the signal processing element (13) and the pulse element (14) are in buffered contact with the inner side wall of the housing (11).

2. The magnetostrictive displacement sensor according to claim 1, wherein, The outer peripheries of the signal processing element (13) and the pulse element (14) are coated with a flexible buffer structure (17). The inner wall of the housing (11) is provided with an abutting groove (1121), and the flexible buffer structure (17) abuts against the abutting groove (1121).

3. The magnetostrictive displacement sensor according to claim 1, characterized in that, A plurality of first fixing holes (164) and a plurality of second fixing holes (163) are respectively provided on opposite sides of the first enclosing plate (161) and the second enclosing plate (162). The signal processing element (13) and the pulse element (14) are respectively fixed in the plurality of first fixing holes (164) and the plurality of second fixing holes (163); There is a heat dissipation air duct (16b) formed between both the signal processing element (13) and the pulse element (14) and the bracket (16).

4. The magnetostrictive displacement sensor (100) according to claim 3, characterized in that, The sensitive element assembly (12) includes a base (121), a shielding cover (122) mounted on one side of the base (121), and a sensitive element board (123). The base (121) and the shielding cover (122) enclose a shielding cavity, and the sensitive element board (123) is disposed in the shielding cavity. On the other side of the base (121), a fiberglass tube (125) is provided. A high-temperature wire (126) and the waveguide wire (127) are provided in the fiberglass tube (125), and the fiberglass tube (125) extends along the length direction of the measuring rod (2).

5. The magnetostrictive displacement sensor according to claim 4, wherein, At one end of the first enclosure plate (161) and the second enclosure plate (162) facing the end cap assembly (15), third fixing holes (165) are provided, and the end cap assembly (15) is fixed to the first enclosure plate (161) and the second enclosure plate (162) through the third fixing holes (165).

6. The magnetostrictive displacement sensor according to claim 3, wherein On one side of the first enclosure plate (161) and the second enclosure plate (162) facing the limiting groove, a fixing groove for the base (121) is provided, and the base (121) is snap-fitted and limited in the fixing groove for the base (121).

7. The magnetostrictive displacement sensor according to any one of claims 1 to 6, characterized in that The end cap assembly (15) includes an end cap plate (151) and a first bolt (152). The end cap plate (151) is screwed to the housing (11) through the first bolt (152); and / or The end cap assembly (15) includes an end cap plate (151). The end cap plate (151) is provided with a clamping protrusion (1513), and the housing (11) is provided with a clamping groove (114). The clamping protrusion (1513) is clamped in the clamping groove (114).

8. The magnetostrictive displacement sensor according to claim 7, characterized in that, The housing (11) includes a front shell (111) and a rear shell (112). The two ends of the rear shell (112) are respectively connected to the front shell (111) and the end cap plate (151). The first bolt (152) sequentially passes through the end cap plate (151) and the rear shell (112) and is screwed and fixed to the front shell (111).

9. The magnetostrictive displacement sensor according to claim 8, wherein, The end cap assembly (15) further includes a power supply board (153). The power supply board (153) is disposed on the side of the end cap plate (151) facing the sensitive element assembly (12) and is located in the accommodating cavity (11a). The power supply board (153) is provided with a connector (1531), and the signal processing element (13) is electrically connected to the power supply board (153) through the connector (1531); On the side of the end cap plate (151) facing away from the power supply board (153), at least one connector (1511) is provided. One end of at least one connector (1511) is electrically connected to the power supply board (153), and the connector (1511) is used for externally connecting a signal source; The front shell (111) is provided with a connection hole communicating the accommodating cavity (11a) and the measuring rod (2). On the side of the front shell (111) facing away from the rear shell (112), a mounting portion is provided; The magnetostrictive displacement sensor (100) further includes a mounting base (113). The mounting base (113) is disposed at one end of the housing (11) close to the measuring rod (2) and is located within the accommodating cavity (11a). The mounting base (113) is detachably disposed on the housing (11).

10. The magnetostrictive displacement sensor according to any one of claims 1 to 6, characterized in that, The magnetostrictive displacement sensor further includes a guide rail (5) arranged along the extending direction of the measuring rod (2) and a slider (4) slidably disposed on the guide rail (5). The cursor (3) is disposed on the slider (4). The slider (4) is provided with a connecting member (41), and the connecting member (41) is disposed on the side facing away from the measuring head (1).

Images