High-precision wide-range displacement sensor based on grating technology

Abstract

The invention relates to a high-precision wide-range displacement sensor based on a grating technology. The device comprises a displacement mechanism; the low-power-consumption induction and self-calibration mechanism comprises a driven gear, a double-meshing gear, a driving gear, an automatic reset component, a driving component and an induction device which are sequentially meshed, the driven gear can receive input torque and sequentially drive the double-meshing gear and the driving gear to rotate, and the double-meshing gear can drive the automatic reset component to move through the driving component. The displacement action of the automatic reset component is sensed through the sensing device; the grating mechanism comprises a grating belt driven shaft, a grating belt driving shaft, a grating belt wheel, a grating belt and a grating decoder, and displacement data are obtained through the grating decoder, or the displacement data on the grating belt are obtained through a distributed optical fiber or a grating demodulator. According to the invention, long-term low-power-consumption or power-consumption-free monitoring and regular self-calibration of equipment are realized, and the device has the advantages of long service life, wide application range, strong stability, strong anti-interference capability and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of displacement sensors, in particular to high-precision and large-range displacement sensors based on grating technology. Background Art

[0002] Displacement sensors are essential in a variety of industrial, automotive and precision engineering applications, as they can accurately measure motion and position. Many types of displacement sensors have been developed, each offering unique advantages suitable for specific purposes. Commonly used sensors include linear variable differential transformers (LVDTs), potentiometer sensors, capacitive sensors, inductive sensors, optical sensors, ultrasonic sensors, magnetostrictive sensors, and piezoelectric sensors. These sensors operate based on different working principles, including inductive measurement, capacitive measurement, optical effect, and piezoelectric effect. Based on the characteristics of these measurement principles, they are used in various measurement environments. For example, LVDTs can ensure high accuracy and reliability in harsh environments, while optical sensors provide extremely high accuracy in small measurements.

[0003] However, despite their widespread adoption, these displacement sensor technologies still have significant limitations. The most important limitation is the trade-off between range and accuracy. High-precision sensors, such as optical and capacitive sensors, are generally limited to shorter measurement ranges, making them less suitable for applications that require large range measurements. Conversely, sensors designed for longer measurement ranges, such as ultrasonic and inductive sensors, sacrifice accuracy, resulting in reduced measurement accuracy. This trade-off between range and accuracy complicates the selection of the appropriate sensor, especially in applications where both are critical.

[0004] At the same time, many displacement sensors require regular calibration to maintain their accuracy. Over time, factors such as environmental conditions, mechanical wear, and material degradation can cause the sensor output value to drift, so regular calibration is required to ensure consistent performance. This calibration requirement increases the maintenance burden, and the calibration process may cause the entire system to shut down.

[0005] Environmental factors can further affect the performance of these sensors. For example, capacitive sensors are highly sensitive to changes in temperature and humidity, resulting in inaccurate measurements. Optical sensors may be hindered by dust, smoke, or other particles that interfere with the light path, and potentiometer sensors are mechanical devices, and wear of the sliding rheostat during long-term use will reduce its service life and reliability. Although inductive sensors and magnetostrictive sensors have a longer service life, they may be affected by nearby metal objects or external magnetic fields, which limits their use scenarios to a certain extent. In addition, although LVDT provides high accuracy and stable performance in harsh environments, it is relatively large and expensive compared to other sensors, and LVDT is sensitive to electromagnetic interference and vibration, which ultimately limits its application scope.

[0006] Although current displacement sensor technology is indispensable in many applications, it has many limitations (such as the contradiction between range and accuracy, the need for regular calibration, and sensitivity to environmental conditions). Therefore, it is urgent to propose a new displacement sensing technology to improve the measurement accuracy and range of the sensor, the anti-interference ability, reduce the maintenance and calibration requirements, and ultimately solve the problems existing in the current displacement sensing technology. Summary of the invention

[0007] To this end, the present invention provides a high-precision and large-range displacement sensor based on grating technology, which has the advantages of long service life, wide application range, strong stability, low power consumption, self-calibration, and strong anti-interference ability.

[0008] In order to solve the above technical problems, the present invention provides a high-precision and large-range displacement sensor based on grating technology, comprising: A displacement mechanism, used to provide input torque when the displacement structure to be measured is displaced; A low-power sensing and self-calibration mechanism, comprising a driven gear, a double meshing gear, a driving gear, an automatic reset component, a driving component and a sensing device that are meshed in sequence, wherein the driven gear can receive the input torque and sequentially drive the double meshing gear and the driving gear to rotate, the double meshing gear can drive the automatic reset component to move through the driving component, and the displacement action of the automatic reset component is sensed by the sensing device, and at the same time, the pulse signal outputted by the driven gear can also provide a relative displacement, and can be used for the displacement calibration of the grating displacement sensor; A grating mechanism comprises a grating belt driven shaft, a grating belt driving shaft, grating belt pulleys respectively connected to the grating belt driven shaft and the grating belt driving shaft, a grating belt connected between the two grating belt pulleys, and a grating decoder matched with the grating belt, wherein the grating belt driving shaft is connected to the driving gear, the grating belt driving shaft can drive the grating belt to move by the rotation of the driving gear, and the displacement data is obtained by the grating decoder; or, the displacement data on the grating belt is obtained by a distributed optical fiber or a grating demodulator.

[0009] In one embodiment of the present invention, a synchronization mechanism is further included, wherein the synchronization mechanism includes a driven synchronization wheel respectively mounted on the driven shaft of the grating belt, a driving synchronization wheel mounted on the driving shaft of the grating belt, a synchronization belt idler wheel, a synchronization belt, and an idler wheel tensioning device; The synchronous belt passes through the synchronous belt idler wheel and is connected between the driven synchronous wheel and the active synchronous wheel; The idler tensioning device adjusts the position of the synchronous belt idler to achieve the tensioning of the synchronous belt.

[0010] In one embodiment of the present invention, it further includes a guide assembly and a gear shaft connected to the middle portion of the double meshing gear; The driving component includes a cam connected to the gear shaft; The automatic reset component includes a slide bar and a stopper disposed on the slide bar and capable of contacting the cam, and both ends of the slide bar are respectively slidably connected to the guide assembly; The sensing device includes a proximity sensor disposed beside the end of the slide bar; The cam can drive the stopper to move when rotating, so that the slide bar slides along its axis and is sensed by the sensing device.

[0011] In one embodiment of the present invention, the guide assembly includes a slide bar spring, a slide bar spring adjustment plate and a slide bar guide block; The slide bar spring is sleeved on the end of the slide bar and abuts against the slide bar spring adjustment plate. The slide bar is slidably connected to the slide bar guide block and its end extends out of the slide bar spring adjustment plate.

[0012] In one embodiment of the present invention, a ratchet mechanism is further included, wherein the ratchet mechanism includes a ratchet mounting plate, a coil spring pressure plate, a ratchet, a pawl, a pawl bearing seat, a ratchet bearing seat, a coil spring and a pawl shaft; The ratchet bearing seat and the pawl bearing seat are mounted on the ratchet mounting plate, the ratchet is mounted on the ratchet bearing seat, the pawl is mounted on the pawl bearing seat through the pawl shaft, and the pawl is in contact with the ratchet; The coil spring is arranged inside the ratchet wheel, the coil spring pressure plate is installed outside the ratchet wheel to prevent the coil spring from popping out, the grating belt main shaft is connected to the coil spring and provides a reset force through the coil spring when the grating belt main shaft rotates; The pawl tension adjustment device comprises a pawl tension adjustment plate, an adjustment bolt assembly and a pawl spring, wherein the adjustment bolt assembly can adjust the pressure of the pawl spring on the pawl.

[0013] In one embodiment of the present invention, the grating mechanism further comprises a grating belt tensioner and a grating belt idler; The grating belt idler is arranged on one side of each grating belt pulley, and the grating belt tensioner is arranged between the two grating belt idlers; One end of the grating belt is coiled on one of the grating belt wheels, and the other end passes through one of the grating belt idler wheels, the grating belt tensioner, and the other grating belt idler wheel in sequence, and then is wound on the other grating belt wheel.

[0014] In one embodiment of the present invention, the grating belt driving wheel shaft is connected to the driving gear via a key, and the axial and radial ends of the driving gear are respectively provided with a gear top screw and a gear spacer; The double-meshing gear is a double-tooth structure, including a double-tooth main wheel and a double-tooth auxiliary wheel. A double-tooth torsion spring is arranged between the double-tooth main wheel and the double-tooth auxiliary wheel. The double-tooth torsion spring can provide a force for the double-tooth auxiliary wheel to press against the driving gear and the driven gear respectively. A double-tooth pressure plate is abutted against the outside of the double-tooth auxiliary wheel.

[0015] In one embodiment of the present invention, the displacement mechanism includes a chain, a chain idler and an input sprocket; the input sprocket is connected to the driven gear through its external input shaft, and both sides of the chain are respectively engaged with the input sprocket and the chain idler.

[0016] In one embodiment of the present invention, the displacement structure to be measured includes a weight rack and a pulley block, and two ends of the chain are respectively connected to the weight rack and the pulley block.

[0017] In one embodiment of the present invention, the displacement mechanism includes an external column, a slide seat, a brush plate, an input wire, a wire capstan, and a wire pressure plate; The wire winch is connected to the driven gear through its external input shaft. An input wire is wound on the wire winch. The input wire is limited on the wire winch by a wire pressure plate. The input wire slides and passes through the brush plate connected to the slide seat.

[0018] The above technical solution of the present invention has the following advantages compared with the prior art: The present invention discloses a high-precision and large-range displacement sensor based on grating technology. The displacement sensor records displacement through a grating belt and calibrates the displacement information on the grating belt through a ratchet mechanism. At the same time, long-term low-power consumption monitoring of the device is achieved through cam triggering. The combined structure of the grating belt and the grating decoder is adopted. The displacement of the grating belt is recorded and calibrated in combination with the ratchet mechanism, thereby ensuring high-precision measurement of the displacement sensor.

[0019] The present invention uses a triggering design of a slide bar, a block, a proximity sensor and a cam, and triggers the sensor only when displacement occurs. It can maintain an extremely low power consumption standby state when not in operation, which is suitable for long-term monitoring tasks and prolongs the use time of the equipment.

[0020] The present invention solves the contradiction between the measurement accuracy and the measurement range of the displacement sensor during the development and use process, and at the same time avoids the problem that traditional sensors need to be calibrated regularly and the calibration process is cumbersome. By measuring and recording the displacement through the grating belt, the present invention has the significant advantages of long service life, wide application range, strong stability and strong anti-interference ability. In addition, the sensor has two built-in displacement measurement methods: electric pulse and grating belt. The grating belt can record the cumulative displacement in the case of power failure, while the electric pulse measurement has higher accuracy. Therefore, the device can calibrate the displacement data recorded by the grating belt through high-precision electric pulse measurement technology to realize the self-calibration function, thereby further improving the reliability and accuracy of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0022] Figure 1 It is the main view of the on-site bridge monitoring displacement in the embodiment of the present invention.

[0023] Figure 2 and Figure 3 It is an overall axial side view of a high-precision and large-range displacement sensor based on grating technology in one embodiment of the present invention. Its transmission modes are chain transmission and wire rope transmission, and the transmission mode is selected according to the usage scenario.

[0024] Figure 4 It is an overall axial side view of a large-range precision grating displacement sensor based on distributed optical fiber sensor technology in another embodiment of the present invention.

[0025] Figure 5 It is a front view of the electric control mechanism of the present invention.

[0026] Figure 6 It is the front view of the grating mechanism of the present invention.

[0027] Figure 7It is a full-section front view of the grating mechanism of the present invention.

[0028] Figure 8 It is a full-section front view of the fiber optic grating series power-saving version mechanism of the present invention.

[0029] Fig. 9 It is a full cross-sectional view of the grating belt driven shaft of the grating mechanism of the present invention.

[0030] Fig.10 It is a full cross-sectional view of the grating belt driving axis of the grating mechanism of the present invention.

[0031] Fig.11 It is a front view of the synchronization mechanism of the present invention.

[0032] Fig.12 It is a front view of the low power consumption sensing and self-calibration mechanism of the present invention.

[0033] Fig.13 It is a full cross-sectional front view of the low power consumption sensing and self-calibration mechanism of the present invention.

[0034] Fig.14 It is a cross-sectional view of the alignment of the low power consumption sensing and self-calibration mechanism of the present invention.

[0035] Fig.15 It is a front view of the ratchet mechanism of the present invention.

[0036] Fig.16 It is a cross-sectional view of the ratchet mechanism alignment of the present invention.

[0037] Fig.17 It is a front view of the sprocket displacement mechanism of the present invention.

[0038] Fig.18 It is a full-section front view of the wire rope displacement mechanism of the present invention.

[0039] Description of the Figures in the Specification: 0.1, vehicle; 0.2, bridge; 0.3, bridge pier; 0.4, fixed point; 0.5, steel wire; 0.6, pulley block; 0.7, low-power displacement device; 0.8, weight rack; 1. Signal processing unit; 11. Internet of Things communication components; 12. Power supply components; 13. Antenna components; 14. Electronic control installation substrate; 2. Grating mechanism; 201, grating decoder; 201A, optical fiber probe; 202, grating belt tensioner; 203, grating belt soft contact; 204, grating belt idler; 205, grating belt; 206, grating belt pulley; 207, grating belt retaining ring; 208, grating belt mounting plate; 209, grating belt driven shaft; 210, grating belt idler shaft; 211, grating belt driving shaft; 212, grating belt pressure plate; 213, grating belt pulley spacer; 214, grating belt bearing seat; 3. Synchronous mechanism; 31. Synchronous belt; 32. Shaft tensioner; 33. Driven synchronous wheel; 34. Active synchronous wheel; 35. Synchronous belt idler; 36. Synchronous idler shaft; 37. Synchronous idler tensioner; 38. Synchronous wheel take-up plate; 4. Low power consumption sensing and self-calibration mechanism; 401, driving gear; 402, proximity mounting plate; 403, proximity sensor; 404, slide bar; 405, slide bar spring; 406, slide bar spring adjustment plate; 407, slide bar guide block; 408, double-piece gear pressure plate; 409, double-piece gear auxiliary wheel; 410, gear set mounting plate; 411, driven gear; 412, double-piece gear main wheel; 413, gear shaft; 414, gear bearing seat; 415, double-piece gear bearing seat; 416, gear spacer; 417, gear top screw; 418, double-piece gear torsion spring; 419, locking piece; 5. Ratchet mechanism; 501, ratchet mounting plate; 502, external input bearing seat; 503, coil spring pressure plate; 504, ratchet; 505, pawl; 506, pawl tension adjustment plate; 507, pawl spring; 508, pawl bearing seat; 509, ratchet bearing seat; 510, coil spring; 511, pawl shaft; 6-A, sprocket displacement mechanism; 60, external input shaft; 61A, chain; 62A, chain idler; 63A, elastic retaining ring; 64A, chain idler shaft; 65A, input sprocket; 6-B, wire rope displacement mechanism; 61B, external column; 62B, slide seat; 63B, outdoor cover; 64B, brush plate; 65B, input wire; 66B, wire capstan; 67B, wire pressure plate. DETAILED DESCRIPTION

[0040] The present invention is further described below in conjunction with the accompanying drawings and specific application cases so that those skilled in the art can better understand and apply the present invention, but the cases are not intended to limit the scope of application of the present invention.

[0041] In the present invention, if directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, and does not indicate or imply that the technical features referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention.

[0042] In the present invention, "several" means one or more, "multiple" means more than two, "greater than", "less than", "exceed" and the like are understood to exclude the number itself; "above", "below", "within" and the like are understood to include the number itself. In the description of the present invention, if there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0043] In the present invention, unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, for example, it can be directly connected or indirectly connected through an intermediate medium; it can be fixedly connected or detachably connected or integrally formed; it can be mechanically connected or electrically connected or able to communicate with each other; it can be the internal connection of two elements or the interaction relationship between two elements. Personnel in the relevant technical field can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0044] Reference Figure 1 As shown, the vehicle is weighed before passing the displacement sensor. After entering the monitoring section, the vehicle speed is obtained through the speedometer. The fixed point 0.4 is installed on the bridge pier 0.3. The other side of the bridge pier 0.3 is installed with a pulley block 0.6 and a low-power displacement sensor device. A steel wire 0.5 is installed between the two bridge piers 0.3. The weight frame 0.8 provides amplified tension to the steel wire 0.5 through the pulley block 0.6 to ensure that the steel wire 0.5 has no bending deformation in the connection state. The low-power displacement device 0.7 is installed below the pulley block 0.6. The displacement between the bridge piers 0.3 can be reflected in the relative displacement of the weight frame 0.8. The low-power displacement device 0.7 can obtain the displacement variable. According to the displacement data of the sensor, the vehicle axle weight and the driving speed, the health of the bridge and the operating status of the monitoring equipment can be rechecked. During the installation process, the equipment does not require auxiliary installation equipment such as scaffolding, adjustment brackets and vertical meters, which greatly reduces the difficulty of on-site installation and shortens the installation time.

[0045] Reference Figure 2 or Figure 3 As shown, the low-power displacement sensor device 0.7 is a high-precision, large-range displacement sensor based on grating technology. The housing and its internal related mechanisms are as follows: A displacement mechanism, used to provide input torque when the displacement structure to be measured is displaced; The low-power sensing and self-calibration mechanism 4 comprises a driven gear 411, a double meshing gear, a driving gear 401, an automatic reset component, a driving component and a sensing device that are meshed in sequence, wherein the driven gear 411 can receive the input torque and sequentially drive the double meshing gear and the driving gear 401 to rotate, the double meshing gear can drive the automatic reset component to move through the driving component, and the displacement action of the automatic reset component is sensed by the sensing device; The grating mechanism 2 includes a grating belt driven shaft 209, a grating belt driving shaft 211, a grating belt pulley 206 respectively connected to the grating belt driven shaft 209 and the grating belt driving shaft 211, a grating belt 205 connected between the two grating belt pulleys 206, and a grating decoder 201 cooperating with the grating belt 205. The grating belt driving shaft 211 is connected to the driving gear 401. The grating belt driving shaft 211 can drive the grating belt 205 to move by the rotation of the driving gear 401, and obtain displacement data through the grating decoder 201 or distributed optical fiber.

[0046] In other embodiments, reference Figure 8 As shown, the grating mechanism 2 includes a grating belt driven shaft 209, a grating belt driving shaft 211, a grating belt pulley 206 connected to the grating belt driven shaft 209 and the grating belt driving shaft 211 respectively, a grating belt 205 connected between the two grating belt pulleys 206, and an optical fiber probe 201A matched with the grating belt 205. The grating belt driving shaft 211 is connected to the driving gear 401. The grating belt driving shaft 211 can drive the grating belt 205 to move through the rotation of the driving gear 401, and the refractive index modulation intensity and grating length are changed by the movement of the grating belt 205. The grating demodulator transmits a light signal of a corresponding wavelength through the optical fiber probe 201A, and obtains the displacement data of the sensor according to the reflection wavelength of the grating belt 205. Multiple low-power displacement devices 0.7 are sequentially connected in series with the optical fiber probe 201A to achieve zero power consumption.

[0047] In addition, a grating belt mounting plate 208, a gear set mounting plate 410 and a ratchet mounting plate 501 are spaced apart inside the shell.

[0048] Reference Fig. 9 As shown, in one embodiment, in order to ensure the synchronous operation of the grating belt driven shaft 209 and the grating belt driving shaft 211, a synchronization mechanism 3 is provided on the grating belt mounting plate 208, and the synchronization mechanism 3 includes a driven synchronous wheel 33 respectively installed on the grating belt driven shaft 209, a driving synchronous wheel 34 installed on the grating belt driving shaft 211, a synchronous belt idler wheel 35, a synchronous belt 31, and an idler wheel tensioning device; the driven synchronous wheel is embedded with a shaft expansion sleeve to facilitate installation; The synchronous belt 31 passes through the synchronous belt idler wheel 35 and is connected between the driven synchronous wheel 33 and the active synchronous wheel 34; The idler tensioning device adjusts the position of the synchronous belt idler 35 to achieve the tensioning of the synchronous belt 31 .

[0049] Specifically, the idler tensioning device includes a synchronous wheel tensioning plate 38 installed on the grating belt mounting plate 208 and a synchronous idler tensioning block 37 movably connected to the synchronous wheel tensioning plate 38. The synchronous idler tensioning block 37 is rotatably connected to a synchronous idler shaft 36 connected to the synchronous belt idler 35. The synchronous idler tensioning block 37 is driven to move by adjusting the adjusting bolt on the tensioning plate of the synchronous belt 31 to complete the tensioning of the synchronous belt 31.

[0050] In one embodiment, referring to Fig.10 As shown, it also includes a guide assembly and a gear shaft 413 connected to the middle part of the double meshing gear; The driving component includes a cam connected to the gear shaft 413; The automatic reset component includes a slide bar 404 and a stopper disposed on the slide bar 404 and capable of contacting the cam, and both ends of the slide bar 404 are slidably connected to the guide assembly respectively; The sensing device includes a proximity sensor 403 disposed beside the end of the slide bar 404, and the proximity sensor 403 is mounted on a proximity mounting plate 402; The cam can drive the stopper to move when rotating, so that the slide bar 404 slides along its axis and is sensed by the sensing device.

[0051] When the cam on the double-toothed main wheel 412 rotates, it drives the slide bar 404 to move, and the slide bar 404 counts the rotations with the proximity sensor 403, thereby realizing low-power counting. When the slide bar 404 triggers the proximity sensor 403, the system can recognize the forward and reverse signals and accumulate the corresponding displacement.

[0052] It is understandable that when the cam rotates clockwise or counterclockwise, it can drive the slide bar 404 to move linearly in two opposite directions and be sensed by the corresponding proximity sensors 403 on both sides. In this way, positive counting and negative counting are realized, thereby realizing displacement recording. However, the power-off device cannot accumulate and record the corresponding position, resulting in loss of recorded data. Therefore, a backup power supply is required, and the battery of the main power supply 12 needs to be replaced in time after the power supply is switched from the main power supply 12 to the backup power supply.

[0053] Reference Fig.11 As shown, the guide assembly includes a slide bar spring 405, a slide bar spring adjustment plate 406 and a slide bar guide block 407; The slide bar spring 405 is sleeved on the end of the slide bar 404 and abuts against the slide bar spring adjustment plate 406 . The slide bar 404 is slidably connected to the slide bar guide block 407 and its end extends out of the slide bar spring adjustment plate 406 .

[0054] Specifically, the proximity mounting plate 402, the slide bar spring adjustment plate 406 and the slide bar guide block 407 are installed on the gear assembly mounting plate 410 by bolts. The slide bar 404 is installed in the slide bar guide block 407. By adjusting the tightness of the slide bar spring adjustment plate 406, the pressure applied by the slide bar spring 405 is adjusted by loosening to ensure that the slide bar 404 has the ability to reset to the center. The proximity sensor 403 detects the number of left and right displacements of the slide bar 404. When the cam on the double-toothed main wheel 412 hits the block on the slide bar 404 and generates a corresponding displacement, the proximity sensor 403 can obtain a signal. When the cam does not contact the block on the slide bar 404, the slide bar 404 is reset by the slide bar spring 405.

[0055] Through the above-mentioned settings, it is possible to trigger the proximity sensor 403 mechanically when displacement occurs, and the signal unit sends the grating decoder 201 to the outside to obtain displacement data. When there is no displacement input, the device remains in a dormant state, and the proximity sensor 403 is mechanically triggered to obtain data when displacement occurs, which significantly reduces the energy consumption of the device under long-term monitoring in the field.

[0056] Ratchet and related structures are used to generate pulse signals caused by displacement, refer to Fig.13 , Fig.14 As shown, it also includes a ratchet mechanism 5, through which the displacement information on the grating belt 205 can be calibrated; the ratchet mechanism 5 includes a ratchet mounting plate 501, a coil spring pressure plate 503, a ratchet 504, a pawl 505, a pawl bearing seat 508, a ratchet bearing seat 509, a coil spring 510 and a pawl shaft 511; the ratchet bearing seat 509 and the pawl bearing seat 508 are installed on the ratchet mounting plate 501, the ratchet 504 is installed on the ratchet bearing seat 509, the pawl 505 is installed on the pawl bearing seat 508 through the pawl shaft 511, and the pawl 505 is in contact with the ratchet 504; the coil spring 510 is provided inside the ratchet 504, the coil spring pressure plate 503 is installed outside the ratchet 504 to prevent the coil spring 510 from popping out, the grating belt driving shaft 205 is connected to the coil spring 510 and provides a reset force through the coil spring 510 when the grating belt driving shaft 205 rotates; the pawl 505 tension adjustment device includes a pawl tension adjustment plate 506, an adjustment bolt assembly and a pawl spring 507, and the adjustment bolt assembly can adjust the pressure of the pawl spring 507 on the pawl 505.

[0057] The coil spring 510 and the ratchet 504 structure realize the automatic resetting function of the device, thereby enhancing the stability and reliability of the system.

[0058] The grating belt records the position information of the sensor, refer to Figures 6 to 8 As shown, the grating mechanism 2 further includes a grating belt tensioner 202 and a grating belt idler 204; The grating belt idler wheel 204 is arranged on one side of each grating belt pulley 206, and the grating belt tensioner 202 is arranged between the two grating belt idler wheels 204; One end of the grating belt 205 is wound around one of the grating belt pulleys 206, and the other end passes through one of the grating belt idler pulleys 204, the grating belt tensioner 202, and another grating belt idler pulley 204 in sequence, and then is wound around another grating belt pulley 206. The grating belt tensioner 202 can prevent the grating belt 205 from being damaged due to excessive tension.

[0059] Specifically, it also includes a grating belt pressing plate 212, a grating belt 205 retaining ring, and a grating belt bearing seat 214. The grating belt pressing plate 212 is used to press the grating belt 205 onto the grating belt pulley 206. The grating belt 205 retaining ring is fixedly installed on the grating belt pulley 206, which can further press the grating belt pressing plate 212 and also provide a certain guiding effect for the winding of the grating belt 205. The grating belt idler shaft 210 is fixed to the grating belt mounting plate 208 by bolts, and the grating belt idler 204 is prevented from axial movement by the shoulder of the grating belt idler shaft 210 and the end face bolts. The grating belt 205 is tensioned by the grating belt tensioner 202 to prevent wrinkles and scratches, so as to avoid interfering with the grating decoder 201 reading data. The grating belt bearing seat 214 is fixedly mounted on the grating belt mounting plate 208 by bolts, and the grating belt pulley 206 is respectively mounted on the grating belt driven shaft 209 and the grating belt driving shaft 211 by key connection, top screw and grating belt pulley spacer 213.

[0060] The cumulative displacement is recorded by the grating belt 205, which avoids the loss of the cumulative displacement data due to power failure and improves the measurement accuracy of the displacement sensor. When powered on, the sensor can measure displacement in two ways: built-in electric pulse and grating belt 205. Therefore, calibration can be achieved by calibrating the grating belt 205 by the built-in electric pulse. This calibration method is simple to operate and has high reliability. The position information of the device is recorded by the grating belt 205 reel, which improves the range of the sensor.

[0061] In one embodiment, referring to Fig.12 As shown, the driving wheel shaft of the grating belt 205 is connected to the driving gear 401 through a key, and the axial and radial ends of the driving gear 401 are respectively provided with a gear top screw 417 and a gear spacer 416; The double meshing gear is a double-tooth structure (i.e., a gear having two teeth), including a double-tooth main wheel 412 and a double-tooth auxiliary wheel 409. A double-tooth torsion spring 418 is provided between the double-tooth main wheel 412 and the double-tooth auxiliary wheel 409. The double-tooth torsion spring 418 can provide a force for the double-tooth auxiliary wheel 409 to press against the driving gear 401 and the driven gear 411 respectively. The double-tooth auxiliary wheel 409 is abutted against a double-tooth pressure plate 408.

[0062] By providing the double-tooth torsion spring 418, it is possible to prevent gear clearance generated when the driving gear 401 and the driven gear 411 mesh with the double meshing gears and perform forward and reverse motion, thereby improving meshing accuracy by offsetting the forward and reverse clearance.

[0063] In the specific configuration, a receiving cavity for installing the double-toothed torsion spring 418 is formed between the double-toothed main wheel 412 and the double-toothed auxiliary wheel 409 , and the double-toothed torsion spring 418 is connected to the circumferential ends of the double-toothed main wheel 412 and the double-toothed auxiliary wheel 409 respectively.

[0064] Specifically, the gear assembly mounting plate 410 is provided with a gear bearing seat 414 and a double-piece gear bearing seat 415, the gear shaft 413 is fixedly mounted on the double-piece gear bearing seat through a shaft shoulder and bolts, and the double-piece gear main wheel 412 is fixedly mounted on the double-piece gear shaft 413 through a key connection and a top screw. The double-piece gear auxiliary wheel 409 is pressed against the double-piece gear main wheel 412 through a double-piece gear pressure plate 408, and the double-piece gear pressure plate 408 is connected to the gear shaft 413 through a locking member 419.

[0065] In one embodiment, referring to Figure 2 , Fig.15 As shown, the displacement mechanism adopts a sprocket displacement mechanism 6-A, including a chain 61A, a chain idler 62A and an input sprocket 65A; the input sprocket 65A is connected to the driven gear 411 through its external input shaft 60, and the two sides of the chain 61A are respectively engaged with the input sprocket 65A and the chain idler 62A.

[0066] The chain 61A is prevented from moving by the input sprocket 65A and the chain 61A idler wheel, and the chain idler wheel shaft 64A is fixedly mounted on the ratchet mounting plate 501, and the chain 61A steering wheel is prevented from moving by the elastic retaining ring. In harsh outdoor conditions, the accuracy is improved.

[0067] The external input shaft 60 is fixed relative to the driven gear 411 by means of a key connection, a top screw and a gasket to transmit power. The external input bearing seat 502 is installed on the ratchet mounting plate 501 and supports the rotation of the external input shaft 60 .

[0068] The displacement structure to be measured includes a weight frame 0.8 and a pulley block 0.6, and both ends of the chain 61A are connected to the weight frame 0.8 and the pulley block 0.6 respectively.

[0069] In one embodiment, referring to Figure 3 , Fig.16 As shown, the displacement mechanism adopts a wire rope displacement mechanism 6-B, including an external column 61B, a slide seat 62B, a brush plate 64B, an input wire 65B, a wire winch 66B, and a wire pressure plate 67B; The wire winch 66B is connected to the driven gear 411 through its external input shaft 60. An input wire 65B (i.e., wire 0.5) is wound around the wire winch 66B. The input wire 65B is limited on the wire winch 66B by a wire pressure plate 67B. The input wire 65B slides and passes through the brush plate 64B connected to the slide seat 62B.

[0070] Among them, the slide seat 62B, the outdoor cover 63B and the brush plate 64B are fixed on the ratchet 504 mounting plate by screws, the wire winch 66B is relatively fixed to the external input shaft 60 by the shoulder, key connection and top screw, and the other end is guided by the slide seat 62B, and is more convenient to connect with other equipment by providing an external column 61B.

[0071] In addition, it also includes a signal processing unit 1 arranged on the housing, the signal processing unit 1 is electrically connected to the above-mentioned grating decoder 201 and the proximity sensor 403, the electric control mechanism 1 includes an Internet of Things communication component 11 (single chip microcomputer, etc.), a power supply component 12, an antenna component 13, and an electric control installation substrate 14. The Internet of Things communication component 11 and the power supply component 12 are installed on the electric control installation substrate 14 by bolts, and the antenna component 13 is stuck on the electric control installation substrate 14 and tightened. The signal processing unit 1 is used to send the acquired displacement data to the host computer.

[0072] In the example based on distributed fiber optic sensing technology, refer to Figure 4 and Figure 8 As shown, the sensor device itself can obtain displacement data without power supply and supports multiple sensors connected in series.

[0073] It is understandable that when the measured object is displaced, the displacement mechanism transmits the displacement torque to the driven gear 411 through the sprocket or wire capstan 66B and other structures, thereby driving the driving gear 401 and the grating belt 205 to move. The displacement of the grating belt 205 is read in real time by the grating decoder 201 that cooperates with it. The grating decoder 201 converts the displacement of the grating belt 205 into a displacement signal and generates displacement data (the built-in electric pulse measurement device also performs displacement measurement synchronously to provide higher-precision displacement data. The data measured by the electric pulse is used to calibrate the cumulative displacement information of the grating belt 205 to ensure the accuracy of the data).

[0074] The displacement data obtained by the grating decoder 201 will be sent to the electric control mechanism 1. If the device is powered off, the grating belt 205 can still record the accumulated displacement. After the device is powered on again, the electric control mechanism 1 will continue to process and calibrate the data of the grating belt 205 to ensure the continuity and accuracy of the data. The stored displacement data includes real-time displacement value and accumulated displacement value.

[0075] After the displacement data is processed, it is sent to the host computer or cloud server through the communication module (antenna 13) for remote monitoring and management. In order to reduce power consumption, the sensor maintains a low-power sleep state when there is no displacement activity, and only wakes up the processor for data processing and transmission when displacement or timing monitoring is sensed.

[0076] Taking the displacement sensor using the sprocket displacement mechanism 6-A as an example, the weight frame 0.8 up and down displacement drives the chain 61A stuck in the sprocket, and the chain 61A drives the sprocket to rotate. Since it is relatively fixed with the external input shaft 60, and the driven gear 411 is relatively fixed with the external input shaft 60, the driven gear 411 rotates accordingly when the sprocket rotates. The driven gear 411 is meshed with the double-tooth main wheel 412, and at the same time, the driven gear 411 and the double-tooth auxiliary teeth offset the forward and reverse clearance, thereby improving the monitoring accuracy. The cam of the double-tooth main wheel 412 distinguishes the forward and reverse signals, and the sliding rod 404 and the proximity sensor 403 complete the low-power counting design. The driving gear 401 is meshed with the double-tooth main wheel 412, and at the same time, the driven gear 411 and the double-tooth auxiliary teeth offset the forward and reverse clearance, thereby improving the monitoring accuracy. The driving gear 401 is fixedly mounted on the driving axle of the grating belt 205 through the keyway and the top screw, and the driving axle of the grating belt 205 is connected to the coil spring 510. When the driving gear 401 rotates, the coil spring 510 is applied with a reset force. The driving axle of the grating belt 205 fixes the grating pulley 206 on the driving axle of the grating belt 205 through the shoulder, key connection and gasket. The driving axle of the grating belt 205 rotates to drive the active synchronous wheel 34, and the two grating pulleys 206 rotate synchronously. When necessary, the displacement data is read by the grating decoder 201. The displacement is recorded by the grating belt 205.

[0077] At the same time, the pulse switch quantity provided by the ratchet mechanism 5 can provide accurate displacement information, and the displacement information on the grating belt 205 can be calibrated according to the accurate displacement information. The cam trigger mechanism can realize long-term low-power monitoring of the device.

[0078] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A high-precision, large-range displacement sensor based on grating technology, characterized in that: include: A displacement mechanism, used to provide input torque when the displacement structure to be measured is displaced; A low-power sensing and self-calibration mechanism (4), comprising a driven gear (411), a double meshing gear, a driving gear (401) and an automatic reset component, a driving component and a sensing device that are meshed in sequence, wherein the driven gear (411) is capable of receiving the input torque and sequentially driving the double meshing gear and the driving gear (401) to rotate, the double meshing gear is capable of driving the automatic reset component to move via the driving component, and the displacement action of the automatic reset component is sensed via the sensing device; A grating mechanism (2) comprises a grating belt driven shaft (209), a grating belt driving shaft (211), a grating belt pulley (206) respectively connected to the grating belt driven shaft (209) and the grating belt driving shaft (211), a grating belt (205) connected between the two grating belt pulleys (206), and a grating decoder (201) matched with the grating belt (205), wherein the grating belt driving shaft (211) is connected to the driving gear (401), the grating belt driving shaft (211) can drive the grating belt (205) to move through the rotation of the driving gear (401), and displacement data is obtained through the grating decoder (201); alternatively, the displacement data on the grating belt (205) is obtained through a distributed optical fiber or a grating demodulator.

2. A high-precision, large-range displacement sensor based on grating technology according to claim 1, characterized in that: It also includes a synchronization mechanism (3), the synchronization mechanism (3) including a driven synchronization wheel (33) respectively mounted on the grating belt driven shaft (209), a driving synchronization wheel (34) mounted on the grating belt driving shaft (211), a synchronization belt idler wheel (35), a synchronization belt (31), and an idler wheel tensioning device; The synchronous belt (31) passes through the synchronous belt idler wheel (35) and is connected between the driven synchronous wheel (33) and the driving synchronous wheel (34); The idler wheel tensioning device adjusts the position of the synchronous belt idler wheel (35) to achieve tensioning of the synchronous belt (31).

3. The high-precision and large-range displacement sensor based on grating technology according to claim 1, characterized in that: It also includes a guide assembly and a gear shaft (413) connected to the middle portion of the double meshing gear; The driving component comprises a cam connected to the gear shaft (413); The automatic resetting component comprises a sliding rod (404) and a stopper arranged on the sliding rod (404) and capable of contacting the cam, and both ends of the sliding rod (404) are respectively slidably connected to the guide assembly; The sensing device comprises a proximity sensor (403) arranged beside the end of the sliding rod (404); The cam can drive the stopper to move when rotating, so that the slide bar (404) slides along its axis and is sensed by the sensing device.

4. The high-precision and large-range displacement sensor based on grating technology according to claim 3, characterized in that: The guide assembly comprises a slide bar spring (405), a slide bar spring adjustment plate (406) and a slide bar guide block (407); The slide bar spring (405) is sleeved on the end of the slide bar (404) and abuts against the slide bar spring adjustment plate (406); the slide bar (404) is slidably connected to the slide bar guide block (407) and its end protrudes from the slide bar spring adjustment plate (406).

5. The high-precision and large-range displacement sensor based on grating technology according to claim 1, characterized in that: Also included is a ratchet mechanism (5), the ratchet mechanism (5) comprising a ratchet mounting plate (501), a coil spring pressure plate (503), a ratchet (504), a pawl (505), a pawl bearing seat (508), a ratchet bearing seat (509), a coil spring (510) and a pawl shaft (511); The ratchet bearing seat (509) and the pawl bearing seat (508) are mounted on the ratchet mounting plate (501), the ratchet (504) is mounted on the ratchet bearing seat (509), the pawl (505) is mounted on the pawl bearing seat (508) via the pawl shaft (511), and the pawl (505) is in contact with the ratchet (504); The coil spring (510) is provided inside the ratchet wheel (504), the coil spring pressure plate (503) is installed outside the ratchet wheel (504) to prevent the coil spring (510) from popping out, the grating belt driving shaft (205) is connected to the coil spring (510) and provides a reset force through the coil spring (510) when the grating belt driving shaft (205) rotates; The ratchet (505) tension adjustment device comprises a ratchet tension adjustment plate (506), an adjustment bolt assembly and a ratchet spring (507), wherein the adjustment bolt assembly is capable of adjusting the pressure of the ratchet spring (507) on the ratchet (505).

6. The high-precision and large-range displacement sensor based on grating technology according to claim 1, characterized in that: The grating mechanism (2) further comprises a grating belt tensioner (202) and a grating belt idler wheel (204); The grating belt idler wheel (204) is arranged on one side of each grating belt wheel (206), and the grating belt tensioner (202) is arranged between the two grating belt idler wheels (204); One end of the grating belt (205) is coiled around one of the grating belt pulleys (206), and the other end passes through one of the grating belt idler pulleys (204), the grating belt tensioner (202), and another grating belt idler pulley (204) in sequence before being wound around another grating belt pulley (206).

7. The high-precision and large-range displacement sensor based on grating technology according to claim 6, characterized in that: The driving wheel shaft of the grating belt (205) is connected to the driving gear (401) via a key, and the axial (413) and radial ends of the driving gear (401) are respectively provided with a gear top screw (417) and a gear spacer (416); The double meshing gear is a double-tooth structure, comprising a double-tooth main wheel (412) and a double-tooth auxiliary wheel (409); a double-tooth torsion spring (418) is provided between the double-tooth main wheel (412) and the double-tooth auxiliary wheel (409); the double-tooth torsion spring (418) can provide a force for the double-tooth auxiliary wheel (409) to press against the driving gear (401) and the driven gear (411), respectively; and a double-tooth pressure plate (408) is abutted against the outside of the double-tooth auxiliary wheel (409).

8. The high-precision and large-range displacement sensor based on grating technology according to claim 1, characterized in that: The displacement mechanism comprises a chain (61A), a chain idler wheel (62A) and an input sprocket (65A); the input sprocket (65A) is connected to the driven gear (411) via its external input shaft (60), and two sides of the chain (61A) are respectively meshed with the input sprocket (65A) and the chain idler wheel (62A).

9. The high-precision and large-range displacement sensor based on grating technology according to claim 8, characterized in that: The displacement structure to be measured comprises a weight frame (0.8) and a pulley block (0.6), and two ends of the chain (61A) are respectively connected to the weight frame (0.8) and the pulley block (0.6).

10. The high-precision and large-range displacement sensor based on grating technology according to claim 1, characterized in that: The displacement mechanism comprises an external column (61B), a slide seat (62B), a brush plate (64B), an input steel wire (65B), a steel wire capstan (66B), and a steel wire pressure plate (67B); The wire capstan (66B) is connected to the driven gear (411) via its external input shaft (60); an input wire (65B) is wound around the wire capstan (66B); the input wire (65B) is limited on the wire capstan (66B) by a wire pressure plate (67B); the input wire (65B) slides and passes through the brush plate (64B) connected to the slideway seat (62B).

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