CN220323552U - Detector based on electromagnetic induction - Google Patents

Abstract

The utility model relates to the technical field of underground pipe fitting detection, in particular to an electromagnetic induction-based detector which comprises an outer shell, wherein the outer shell is downwards opened, four rollers are fixedly arranged on two sides of the outer shell, a push rod is fixedly connected to one side of the top surface of the outer shell, a detection device is arranged on the outer shell and comprises a first stop block, a detection box, a transmitting coil, a receiving coil, a sliding groove, a sliding block, a first spring, a clamping groove and a clamping hole. According to the utility model, the detection device is arranged, when the device passes through an uneven road surface, the convex part of the road surface presses the inclined surface of the first check block, the first check block is pressed upwards by utilizing the component force of the pressing force in the vertical direction, so that the sliding block moves out of the clamping groove and is clamped into the clamping hole, and the first check block is fixed, so that the detection box is lifted away from the convex ground, and the damage to the detection box caused by the convex part of the road surface is avoided, and the service life is influenced.

Description

Detector based on electromagnetic induction

Technical Field

The utility model relates to the technical field of underground pipe fitting detection, in particular to a detector based on electromagnetic induction.

Background

The pipeline detector can rapidly and accurately detect the position, trend, depth and position and size of a damaged point of an anticorrosive layer of an underground tap water pipeline, a metal pipeline, a cable and the like under the condition of not damaging earth coverage of the ground, is one of necessary instruments for tap water companies, gas companies, railway communication, municipal construction, engineering and mining, infrastructure unit reconstruction, maintenance and general survey of underground pipelines, and generally uses the metal detector for detecting the metal pipeline, wherein the metal detector has high performance and is specially designed for security protection, and three main categories are: electromagnetic induction type, X-ray detection type, and microwave detection type are electronic instruments for detecting metals.

In the prior art, when the existing underground pipeline detector detects an underground metal pipeline, when a convex obstacle appears locally, the existing underground pipeline detector cannot provide good protection for the probe, and the probe is possibly damaged by collision, so that unnecessary loss is caused. The Chinese patent discloses an underground metal pipeline detector based on an electromagnetic induction mechanism, the publication number is 111913222, and when the convex obstacle appears on the detected road surface, the transmitting coil and the receiving coil can be quickly retracted into the shell of the detector for protection, so that the detector is prevented from being damaged by the obstacle.

The above-mentioned prior art can carry out certain protection to the detector, but in its continuous driving process, meet protruding road then, when the position between the easy bellied position that makes the road surface moves to two baffles, lose contact with the baffle to make two baffles reset simultaneously, block the bellied position in road surface, make the road surface protruding unable through the baffle, lead to the device unable to continue to travel, need the manual work to lift up tester front side or rear side and remove, make protruding road surface motion to the outside of detector shell, can continue to travel, use very inconveniently. In view of this, we propose a detector based on electromagnetic induction.

Disclosure of Invention

The utility model aims to provide a detector based on electromagnetic induction, which solves the problems in the background technology.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

the utility model provides a detector based on electromagnetic induction, includes the shell body, the shell body downward opening sets up, the both sides fixed mounting of shell body has four gyro wheels, top surface one side fixedly connected with push rod of shell body, be provided with detection device on the shell body, detection device is including dog one, detection case, transmitting coil, receiving coil, spout, slider, spring one, draw-in groove, dog one is through spacing post and spacing groove sliding connection on the inner wall of shell body, detection case fixed mounting is on one side of dog one, transmitting coil fixed mounting is in the bottom surface center department of detection case, two receiving coil respectively fixed mounting is on the bottom surface both sides of detection case, and two receiving coil symmetry sets up in transmitting coil both sides, the spout is seted up on one side of keeping away from the detection case of dog, slider sliding connection is in the spout, spring one end and spout fixed connection, draw-in groove is seted up on the inner wall of shell body, equidistant on the draw-in groove is all set up on the draw-in groove.

Preferably, the shell body is further provided with a marking device, the marking device comprises a storage box, a filling hopper, a discharging channel, a partition plate, an electric telescopic rod and a spring telescopic rod, the storage box is fixedly embedded on the top surface of the shell body, the filling hopper is fixedly connected in a filling hole formed in the top surface of the storage box, the discharging channel is fixedly connected in a discharging hole formed in the bottom surface of the storage box, the partition plate penetrates one side of the discharging channel and is in sliding connection with the discharging channel, the width of the partition plate is equal to the width of the inner section of the discharging channel, the electric telescopic rod is fixedly installed on the bottom surface of the outer wall of the storage box through a mounting seat, the positive electrode and the negative electrode of the electric telescopic rod are respectively in electric connection with two receiving coils, the movable end of the electric telescopic rod penetrates one side of the discharging channel and is in sliding connection with the discharging channel, and the spring telescopic rod is fixedly installed on the bottom surface of the outer wall of the storage box through a mounting plate.

Preferably, the detecting device further comprises a movable sleeve, a pressing plate, a second spring, a fixed plate and a second stop block, wherein the movable sleeve is clamped and connected in positioning through grooves formed in two sides of the outer wall of the outer shell in a sliding mode, the pressing plate is fixedly connected to the inner wall of one side of the movable sleeve at equal intervals, each pressing plate corresponds to one clamping hole, one end of the second spring is fixedly connected with the outer wall of the outer shell, the other end of the second spring is fixedly connected with the inner wall of the movable sleeve, the fixed plate is fixedly connected to the inner wall of one side, away from the pressing plate, of the movable sleeve, the fixed plate penetrates through one side of the outer shell and is connected with the outer shell in a sliding mode, and the second stop block is arranged on the inner wall, away from the first stop block, of the outer shell in a sliding mode through a limiting column and the limiting groove.

Preferably, when the first spring is in a natural state, one section top surface that the slider stretches out of the spout is inclined, through setting up the inclined plane, guarantee to drive the slider at dog one and move up the in-process, the slider inclined plane can retract into the spout after being extruded by the shell body, can not block the upward movement of dog one, one side that the slider kept away from the spout is smooth protruding cambered surface setting, through setting up smooth convex surface, at the slider in-process that the shell body slides relatively, reduces frictional force, and then reduces wearing and tearing, increase of service life.

Preferably, the thickness of the sliding block is smaller than the height of the clamping groove and the clamping hole, and the width of the sliding block is smaller than the width of the clamping groove and the clamping hole, so that the sliding block can be fully inserted into the clamping groove and the clamping hole by the aid of the size, and accordingly the first stop block is fixed at different height positions.

Preferably, when the second spring is in a natural state, the bottom surface of the section of the fixing plate positioned in the groove of the outer shell is inclined, the inclined surface is arranged to generate a component force in the horizontal direction by extruding the inclined surface when the second stop block is stressed to rise, the fixing plate is extruded out of the outer shell, so that the movable sleeve horizontally slides, one side of the fixing plate, which is far away from the movable sleeve, is provided with a smooth convex cambered surface, and the friction force is reduced in the sliding process of the second stop block relative to the fixing plate by arranging the smooth convex surface, so that the abrasion is reduced, and the service life is prolonged.

Preferably, two faces that dog two and dog one separate all laminate with the inner wall of shell body, the fixed plate is located the minimum distance of stripper plate and shell body inner wall all the time equal to in shell body inslot one section length, sets up like this and makes at dog two to reciprocate, when extruding the fixed plate outside the shell body inslot, stripper plate one side flushes with shell body inner wall just to make the stripper plate extrude the draw-in hole completely with the slider, and the stripper plate can not stretch into the spout, guarantees that dog one can not receive external force to block, only receives gravity effect decline to reset.

Preferably, the bottom of one side of the push rod is smooth cambered surface, through setting up smooth cambered surface, guarantee that detector horizontal movement in-process, behind dog one or the dog two and the protruding portion contact on ground, the horizontal pressure of ground pair dog one or dog two can produce the component to extrude dog one or dog two vertical upward movement, trigger detection device's safeguard function, make the detector can be relaxed through protruding ground and can not harm the detection case, when dog two does not receive external force effect with dog one, the bottom surface is in same level height, and this height is higher than the minimum height of gyro wheel, and when setting up highly can guarantee that the detector passes through horizontal road surface like this, dog one and dog two can not contact with the road surface, reduce frictional force, reduce the required strength of pushing the detector, reduce the wearing and tearing of dog one and dog two simultaneously, increase of service life.

By means of the technical scheme, the utility model provides a detector based on electromagnetic induction. The method has at least the following beneficial effects:

(1) According to the utility model, the detection device is arranged, when the device passes through an uneven road surface, the convex part of the road surface presses the inclined surface of the first stop block, the first stop block is pressed upwards by utilizing the component force of the extrusion force in the vertical direction, so that the sliding block moves out of the clamping groove and is clamped into the clamping hole, the first stop block is fixed, the detection box is lifted away from the raised ground, the convex part of the road surface is prevented from scraping the detection box and influencing the service life, when the convex part moves to the second stop block, the second stop block can be pressed by the fixing plate, the movable sleeve is horizontally moved, the sliding block is pushed out of the clamping hole by the pressing plate, the first stop block carries the detection box to be lowered by gravity, and after the convex part of the ground completely passes through the second stop block, the movable sleeve is reset under the action of the second spring, so that the next passing through the uneven road surface is facilitated.

(2) According to the utility model, the marking device is arranged, when the detection box detects a metal pipeline, electromotive forces generated in the two receiving coils are unequal, induced currents are generated, so that the electric telescopic rod is electrified to work, the movable end of the electric telescopic rod stretches and pushes the partition plate, the discharging channel is smooth, marking powder in the storage box is discharged and falls to the detection part, subsequent excavation is facilitated, a marking mode of nailing and drilling is replaced, continuous operation can be performed without stopping the movement of the outer shell, time is saved, and construction efficiency is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this application:

FIG. 1 is a schematic diagram of the overall structure of the present utility model;

FIG. 2 is a schematic view of the structure of the movable sleeve of the present utility model after being cut away;

FIG. 3 is a cross-sectional view of the overall structure of the present utility model;

FIG. 4 is a cross-sectional view of a stop according to the present utility model;

FIG. 5 is a cross-sectional view of a marking device of the present utility model.

In the figure: 1. an outer housing; 2. a roller; 3. a push rod; 4. a detection device; 401. a first stop block; 402. a detection box; 403. a transmitting coil; 404. a receiving coil; 405. a chute; 406. a slide block; 407. a first spring; 408. a clamping groove; 409. a clamping hole; 410. a movable sleeve; 411. an extrusion plate; 412. a second spring; 413. a fixing plate; 414. a second stop block; 5. marking means; 501. a storage tank; 502. a filling hopper; 503. a discharge channel; 504. a partition plate; 505. an electric telescopic rod; 506. a spring telescopic rod.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Example 1

Referring to fig. 1-5, the present utility model provides a technical solution:

the utility model provides a detector based on electromagnetic induction, includes shell body 1, and shell body 1 downwardly opening sets up, and shell body 1's both sides fixed mounting has four gyro wheels 2, and shell body 1's top surface one side fixedly connected with push rod 3 is provided with detection device 4 on the shell body 1.

Further, the detecting device 4 comprises a first block 401, a detecting box 402, a transmitting coil 403, receiving coils 404, a chute 405, a slide block 406, a first spring 407, a clamping groove 408 and a clamping hole 409, wherein the first block 401 is slidably connected to the inner wall of the outer shell 1 through a limit post and a limit groove, the detecting box 402 is fixedly arranged on one side of the first block 401, the transmitting coils 403 are fixedly arranged at the center of the bottom surface of the detecting box 402, the two receiving coils 404 are respectively fixedly arranged on two sides of the bottom surface of the detecting box 402, the two receiving coils 404 are symmetrically arranged on two sides of the transmitting coils 403, the chute 405 is arranged on one side of the first block 401 far away from the detecting box 402, the slide block 406 is slidably connected in the chute 405, one end of the first spring 407 is fixedly connected with the chute 405, the other end of the first spring 407 is fixedly connected with the slide block 406, and when the first spring 407 is in a natural state, the sliding block 406 extends out of the top surface of the sliding groove 405 to be obliquely arranged, the inclined surface is arranged to ensure that the sliding block 406 can be retracted into the sliding groove 405 after being extruded by the outer shell 1 in the process that the first sliding block 401 drives the sliding block 406 to move upwards, the upward movement of the first sliding block 401 is not blocked, one side of the sliding block 406 away from the sliding groove 405 is arranged to be a smooth convex surface, the friction force is reduced in the sliding process of the sliding block 406 relative to the outer shell 1 through the smooth convex surface, the abrasion is further reduced, the service life is prolonged, the clamping grooves 408 are formed on the inner wall of the outer shell 1, the clamping holes 409 are formed on the outer shell 1 at equal intervals, the clamping holes 409 are all arranged right above the clamping grooves 408, the thickness of the sliding block 406 is smaller than the heights of the clamping grooves 408 and the clamping holes 409, the width of the sliding block 406 is smaller than the widths of the clamping grooves 408 and the clamping holes 409, the setting size can ensure that the sliding block 406 can be completely inserted into the clamping grooves 408 and the clamping holes 409, thereby securing the first stop 401 in a different height position.

Still further, still be provided with marking device 5 on shell body 1, marking device 5 is including bin 501, annotate hopper 502, discharge channel 503, baffle 504, electric telescopic handle 505, spring telescopic handle 506, bin 501 is fixed to be inlayed on the top surface of shell body 1, annotate hopper 502 fixed connection is in the injection hole of seting up on the top surface of bin 501, discharge channel 503 fixed connection is in the discharge hole of seting up on the bottom surface of bin 501, baffle 504 runs through one side of discharge channel 503 and with discharge channel 503 sliding connection, baffle 504 width equals the interior cross-section width of discharge channel 503, electric telescopic handle 505 passes through mount pad fixed mounting on the outer wall bottom surface of bin 501, electric telescopic handle 505's positive and negative pole respectively with two receiving coil 404 electric connection, electric telescopic handle 505's active end runs through one side of discharge channel 503 and with discharge channel 503 sliding connection, spring telescopic handle 506 passes through mounting panel fixed mounting on the outer wall bottom surface of bin 501, spring telescopic handle 506's active end and baffle 504 stretch out one side of discharge channel 503 fixed connection.

In addition, the detecting device 4 further comprises a movable sleeve 410, a squeezing plate 411, a second spring 412, a fixed plate 413 and a second stop block 414, wherein the movable sleeve 410 is clamped and connected in a positioning through groove formed in two sides of the outer wall of the outer shell 1 in a sliding manner, the squeezing plates 411 are fixedly connected to the inner wall of one side of the movable sleeve 410 at equal intervals, each squeezing plate 411 corresponds to one clamping hole 409, one end of the second spring 412 is fixedly connected with the outer wall of the outer shell 1, the other end of the second spring 412 is fixedly connected with the inner wall of the movable sleeve 410, the fixed plate 413 is fixedly connected to the inner wall of one side of the movable sleeve 410 away from the squeezing plate 411, the fixed plate 413 penetrates through one side of the outer shell 1 and is connected with the outer shell 1 in a sliding manner, when the second spring 412 is in a natural state, one section of bottom surface of the fixed plate 413, which is positioned in the groove of the outer shell 1, is obliquely arranged, and the inclined surface can generate a component force in the horizontal direction through the extrusion inclined surface when the second stop block 414 is stressed to rise, the fixed plate 413 is extruded out of the outer shell 1, the movable sleeve 410 is horizontally slid, one side of the fixed plate 413 far away from the movable sleeve 410 is provided with a smooth convex arc surface, friction force is reduced in the sliding process of the second stop block 414 relative to the fixed plate 413, abrasion is further reduced, service life is prolonged, the second stop block 414 is slidably connected to the inner wall of the outer shell 1 far away from the first stop block 401 through a limit post and a limit groove, the second stop block 414 is arranged on the lower side of the fixed plate 413, two surfaces of the second stop block 414 and the first stop block 401 are respectively attached to the inner wall of the outer shell 1, one section of the fixed plate 413 in the groove of the outer shell 1 is always equal to the minimum distance between the extrusion plate 411 and the inner wall of the outer shell 1, the arrangement is such that when the second stop block 414 moves upwards, one side of the extrusion plate 411 is exactly flush with the inner wall of the outer shell 1 when the fixed plate 413 is extruded out of the groove of the outer shell 1, therefore, the extrusion plate 411 can completely extrude the sliding block 406 out of the clamping hole 409, and the extrusion plate 411 does not extend into the sliding groove 405, so that the first stop block 401 can be prevented from being blocked by external force and can be lowered and reset only under the action of gravity.

It is worth noting that the bottom of one side of the first baffle block 414 and the bottom of the second baffle block 401 far away from the push rod 3 are smooth cambered surfaces, by arranging the smooth cambered surfaces, in the horizontal movement process of the detector, after the first baffle block 401 or the second baffle block 414 contacts with the ground bulge, the horizontal pressure of the first baffle block 401 or the second baffle block 414 can generate component force in the vertical direction, so that the first baffle block 401 or the second baffle block 414 is extruded to vertically move upwards, the protection function of the detector 4 is triggered, the detector can easily pass through the bulge ground and cannot damage the detection box 402, when the bottom surface of the second baffle block 414 and the first baffle block 401 are not affected by external force, the bottom surface is at the same level, and the height is higher than the lowest height of the roller 2, so that the setting height can ensure that the first baffle block 401 and the second baffle block 414 cannot contact with the road surface when the detector passes through the horizontal road surface, friction force is reduced, force required by pushing the detector is reduced, abrasion of the first baffle block 401 and the second baffle block 414 is reduced, and service life is prolonged.

The electrical components and devices in this embodiment are all existing devices known in the art, and the protection of the present utility model does not relate to improvement of the internal structures of these devices, and the electrical components and devices in this embodiment are all electrically connected to a main controller and a mobile power supply mounted on the outer casing 1, and the main controller may be a conventionally known device for controlling a computer or the like.

When the detector based on electromagnetic induction is used, after the detector is transported to a construction site, a certain amount of marking powder is injected into the storage box 501 through the injection hopper 502 for temporary storage, after the injection is finished, the push rod 3 is held to push the detector, and the detector can move on a construction site under the action of the roller 2 to detect underground metal pipelines on the construction site.

The circuit where the transmitting coil 403 is controlled to be started is controlled to enable the transmitting coil 403 to generate a magnetic field, when no metal pipeline exists in the ground, electromotive forces generated in the magnetic field by the two receiving coils 404 are equal, and no potential difference exists between the two receiving coils 404; when a metal pipeline exists under the ground, the electromotive forces generated in the two receiving coils 404 are unequal under the interference of the metal pipeline, namely, potential difference exists between the two receiving coils 404, and current is generated, so that the electric telescopic rod 505 is electrified to work, and when the electric telescopic rod 505 works, the movable rod pushes the partition plate 504 to move horizontally, so that the discharging channel 503 is unblocked, and marking powder in the storage tank 501 is scattered on the ground through the discharging channel 503; when the detector is driven away from the upper part of the metal pipeline, the electromotive force of the two receiving coils 404 is equal again, the electric telescopic rod 505 is powered off, the partition plate 504 is reset under the thrust of the spring telescopic rod 506, and the discharging channel 503 is blocked again. The ground with the metal pipe buried below is marked in this way, so that the subsequent excavation maintenance is convenient.

In the detection process, when the detector passes through the raised ground, the cambered surface of the first stop block 401 is contacted with the raised ground, the raised part extrudes the first stop block 401, the first stop block 401 is limited by the slide rail and can only vertically slide, and the component force of the pressure in the vertical direction pushes the first stop block 401 to vertically rise until the bottom of the first stop block 401 is flush with the top of the bottom of the protrusion, and at the moment, the sliding block 406 is separated from the clamping groove 408 and clamped in the clamping hole 409 at the corresponding position, so that the first stop block 401 and the detection box 402 are fixed in position; the first check block 401 is lifted up to lift the detection box 402, so that the lowest position of the detection box 402 is always higher than the lowest position of the first check block 401, and the transmitting coil 403 and the receiving coil 404 are prevented from being scratched by contact with the ground.

The detector is pushed to continuously advance until the raised ground is contacted with the second block 414, the second block 414 is extruded by the raised ground and vertically slides upwards, in the process of sliding the second block 414 upwards, the fixed plate 413 is extruded, the fixed plate 413 drives the movable sleeve 410 to horizontally slide, so that the extrusion plate 411 horizontally moves to extrude the sliding block 406 in the clamping hole 409, the sliding block 406 is extruded out of the clamping hole 409 and is retracted into the sliding groove 405, at the moment, the first block 401 is separated from the clamping connection, the first block 401 and the detection box 402 vertically descend under the action of gravity, finally reset, and the sliding block 406 is clamped in the clamping groove 408 again under the action of the first spring 407, so that the first block 401 is kept stable.

After the protruding portion on the ground passes through the second stop block 414 completely, the second stop block 414 descends by gravity and finally resets, at this time, the second stop block 414 loses the extrusion to the fixed plate 413, the elastic force generated by the deformation of the second spring 412 pushes the movable sleeve 410 to reset, at this time, all structures reset completely, so that the next protruding ground can be conveniently handled, and the detection work in the whole process is continuously carried out.

It should be noted that in this document, relational terms such as first and second, and the like are used to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. The utility model provides a detector based on electromagnetic induction, includes shell body (1), shell body (1) downwardly opening sets up, its characterized in that: the device is characterized in that the outer shell (1) is connected with a roller (2), the outer shell (1) is connected with a push rod (3), and the outer shell (1) is provided with a detection device (4);

the detection device (4) comprises a first stop block (401), a detection box (402), a transmitting coil (403), a receiving coil (404), a sliding groove (405), a sliding block (406), a first spring (407), a clamping groove (408) and a clamping hole (409), wherein the first stop block (401) is connected in the outer shell (1) in a sliding mode, the detection box (402) is connected to the first stop block (401), the transmitting coil (403) is connected to the detection box (402), the receiving coil (404) is connected to the detection box (402), the sliding groove (405) is formed in the first stop block (401), the sliding block (406) is connected in the sliding groove (405) in a sliding mode, one end of the first spring (407) is connected with the sliding groove (405), the other end of the first spring (407) is connected with the sliding block (406), the clamping groove (408) is formed in the outer shell (1), and the clamping hole (409) is formed in the outer shell (1).

2. The electromagnetic induction-based detector according to claim 1, wherein: still be provided with marking device (5) on shell body (1), marking device (5) are including bin (501), annotate hopper (502), discharge channel (503), baffle (504), electric telescopic handle (505), spring telescopic handle (506), bin (501) are connected on shell body (1), annotate hopper (502) and connect on bin (501), discharge channel (503) are connected on bin (501), baffle (504) and discharge channel (503) sliding connection, electric telescopic handle (505) are connected on bin (501), electric telescopic handle (505) and discharge channel (503) sliding connection, spring telescopic handle (506) are connected at bin (501), spring telescopic handle (506) are connected with baffle (504).

3. The electromagnetic induction-based detector according to claim 1, wherein: the detection device is characterized in that the detection device (4) further comprises a movable sleeve (410), a squeezing plate (411), a second spring (412), a fixed plate (413) and a second stop block (414), wherein the movable sleeve (410) is connected to the outer shell (1), the squeezing plate (411) is connected to the movable sleeve (410), one end of the second spring (412) is connected with the outer shell (1), the other end of the second spring (412) is connected with the movable sleeve (410), the fixed plate (413) is connected to the movable sleeve (410), the fixed plate (413) is in sliding connection with the outer shell (1), and the second stop block (414) is in sliding connection with the outer shell (1).

4. The electromagnetic induction-based detector according to claim 1, wherein: when the first spring (407) is in a natural state, the top surface of a section of the sliding block (406) extending out of the sliding groove (405) is obliquely arranged, and one side of the sliding block (406) away from the sliding groove (405) is provided with a smooth convex cambered surface.

5. The electromagnetic induction-based detector according to claim 1, wherein: the thickness of the sliding block (406) is smaller than the heights of the clamping groove (408) and the clamping hole (409), and the width of the sliding block (406) is smaller than the widths of the clamping groove (408) and the clamping hole (409).

6. A detector based on electromagnetic induction according to claim 3, characterized in that: when the second spring (412) is in a natural state, the bottom surface of a section of the fixed plate (413) positioned in the groove of the outer shell (1) is obliquely arranged, and one side of the fixed plate (413) away from the movable sleeve (410) is provided with a smooth convex cambered surface.

7. A detector based on electromagnetic induction according to claim 3, characterized in that: two surfaces of the second stop block (414) and the first stop block (401) which are separated from each other are attached to the inner wall of the outer shell (1), and the length of one section of the fixing plate (413) positioned in the groove of the outer shell (1) is always equal to the minimum distance between the extrusion plate (411) and the inner wall of the outer shell (1).

8. A detector based on electromagnetic induction according to claim 3, characterized in that: the bottom of one side of the second stop block (414) and the first stop block (401) far away from the push rod (3) is a smooth cambered surface, and when the second stop block (414) and the first stop block (401) are not affected by external force, the bottom surfaces are at the same horizontal height, and the height is higher than the lowest height of the roller (2).