CN103528733B - Spindle-shaped sensor for monitoring load and temperature of flexible rope in real time - Google Patents

Abstract

The invention discloses a spindle-shaped sensor for monitoring the load and the temperature of a flexible rope in real time. The spindle-shaped sensor comprises a spindle-shaped structural frame, an equal-strength cantilever, a support pillar, FBGs (fiber bragg gratings) and separation casings, wherein the spindle-shaped structural frame comprises two arch structures, and the equal-strength cantilever provided with the support pillar is connected with one side of one tip of the spindle shape; through holes are formed in the two tips of the spindle shape and the top of the support pillar, and the to-be-monitored flexible rope sequentially passes through each through hole for fixation; grooves are axially formed in upper and lower surfaces of the equal-strength cantilever and used for pasting the FBGs symmetrically; and one part, which is sleeved with the separation casing, of each grating region serves as a temperature measuring unit, the other part, which is not sleeved with the separation casing, serves as a loading unit, the FBGs are completely and fixedly pasted in the grooves of the equal-strength cantilever after sleeved with the separation casings, and then potting and coating are performed on the FBGs and the separation casings through epoxy glue. According to the spindle-shaped sensor, the problem of simultaneous measurement of the load and the temperature of the flexible rope is solved, the FBGs are effectively protected, and the spindle-shaped sensor is small, light and good in sensitivity, reliability and stability.

Description

Shuttle sensor for real-time monitoring of flexible rope load and temperature

technical field

The invention belongs to the technical field of sensors, in particular to a FBG (Fiber Bragg Grating, Fiber Bragg Grating)-based shuttle sensor for real-time monitoring of flexible rope load and temperature.

Background technique

In the prior art, the flexible rope used in industry has the characteristics of being soft and easy to bend and deform, small diameter, uneven surface, and usually used in a hidden environment, which makes it difficult to measure the load in the rope.

At present, the method of measuring the load of the flexible rope is usually to use an electromagnetic tension tester. The new patented "cable tension measuring instrument" provides related measurement methods. However, this method is difficult to realize real-time tracking and monitoring of dynamic load changes of flexible ropes, and the size of the device is large, the measurement range is small, the sensitivity is low, it is easily interfered by electromagnetic signals, the long-term stability is poor, the life is low, and the simultaneous measurement of load and temperature cannot be realized. It is necessary to develop a fiber grating sensor that can monitor the load and temperature of the flexible rope in real time to overcome the above shortcomings.

FBG is an optical waveguide device formed by introducing periodic refractive index modulation into the optical fiber. By detecting the reflected or transmitted Bragg wavelength spectrum of the grating written inside the optical fiber, the absolute measurement of the stress and temperature of the measured structure can be realized. It has the advantages of high sensitivity, high precision, light weight, small size, corrosion resistance, low cost, bendable optical path, free from electromagnetic interference, easy to realize long-distance and long-term monitoring, and multiple fiber gratings can be transmitted by one optical cable , it is convenient to form a sensing system and realize quasi-distributed measurement. Because it has the above-mentioned characteristics superior to traditional optical measurement and electrical measurement, it has been widely used since its inception. However, due to the small diameter of the bare fiber, poor shear resistance, and the complex axial strain of the flexible rope in the process of loading and stretching, it is difficult to measure by directly pasting the bare fiber. Therefore, the bare fiber is packaged to be able to monitor the load and Temperature sensors are of great significance.

In summary, how to develop a sensor that can simultaneously measure the load and temperature of the flexible rope has become an urgent technical problem to be solved.

Contents of the invention

The technical problem to be solved by the present invention is to provide a shuttle sensor for real-time monitoring of the load and temperature of the flexible rope to solve the problem of how to simultaneously measure the load and temperature of the flexible rope.

In order to solve the above technical problems, the present invention provides a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope, which is characterized in that it includes: a support unit, a bearing unit and a sensing unit, wherein,

The supporting unit includes: a shuttle-shaped frame composed of two arched structures;

The bearing unit includes: equal-strength cantilever beams and support columns;

The sensing unit includes: a fiber grating and a separation sleeve;

The outer frame of the sensor shuttle structure is composed of two arched symmetrical structures. The two tips of the outer frame of the shuttle structure are thinner and thicker in the middle. The wider side of the tip is connected to a cantilever beam of equal strength; the position of the cantilever beam of equal strength away from the root protrudes as a support column, and the support column is perpendicular to the plane of the cantilever beam of equal strength and is located at the center of the overall axial direction; the support The top of the column is provided with through holes, and the two tips of the outer frame of the shuttle-shaped structure are symmetrically provided with through holes; the center of the upper and lower surfaces of the equal-strength cantilever beam is axially provided with grooves near the root; wherein, the two grooves are symmetrical A sensor unit with simultaneous measurement of temperature and load is pasted;

The fiber grating is pasted and fixed in the groove of the equal-strength cantilever beam by using a single-grating separation and pasting technology.

Further, wherein, the distances between the support columns and the two through holes are equal.

Further, wherein, the two arches, equal-strength cantilever beams and support columns are all cut from an integral structure.

Further, wherein, the isosceles trapezoidal shape of the equal-strength cantilever beam.

Further, wherein, the single grating separation and pasting technology is further: a part of the grating area of the fiber grating is socketed with a separation sleeve whose inner diameter is slightly larger than the diameter of the fiber grating, and the fiber grating is sleeved with the separation sleeve The connected part is the temperature measurement unit, and the unsocketed part is the load measurement unit. After the fiber grating and the separation sleeve are connected, they are completely pasted and fixed in the groove of the cantilever beam with equal strength, and then the optical fiber is fixed by epoxy glue. Gratings and separation sleeves are pot-coated.

Further, wherein, the separation sleeve is a film sleeve with a thickness less than 100 μm, and its material is PBT, PP, PC, PET or PVC.

Further, wherein, the diameters of the two tips of the shuttle of the sensor and the through hole on the support column are slightly larger than the diameter of the flexible rope.

In summary, compared with the prior art, the shuttle-shaped sensor for real-time monitoring of flexible rope load and temperature of the present invention has the following advantages and outstanding effects:

1. The sensor as a whole is composed of two arched symmetrical structures, which are in the shape of a shuttle, and the arched top view is an isosceles trapezoid. The two tips of the fusiform are thinner and thicker in the middle, and the size of the two tips is narrower at one end and wider at the other end. The tip of the shuttle is wider and one end side wall is connected to a cantilever beam of equal strength. The position of the cantilever beam of equal strength away from the root protrudes as a support column. The support column is perpendicular to the base plane and is located in the center of the overall axial direction. The top of the support column is drilled. The sidewalls of the two pointed ends of the shuttle are drilled symmetrically. Grooves are axially engraved on the center of the upper and lower surfaces of the equal-strength cantilever beam near the root. The two arches, equal-strength cantilever beams and supporting columns are all integral structures.

2. Since the present invention is based on fiber gratings and is fixed in the groove of an equal-strength cantilever beam by adopting a simple single grating separation and pasting technology, the simultaneous measurement of the load and temperature of the flexible rope can be realized.

3. The sensor of the present invention is small in size, light in weight, simple in structure, easy to assemble and disassemble, low in cost, ingenious in design, beautiful in appearance, has little influence on the measured object, and is easy to package and operate. The fiber grating can be effectively protected, and the measurement It will not be hooked to other ropes in the working environment; it has high sensitivity, high precision, and is free from electromagnetic interference; it can simultaneously and real-time measure the load and temperature of the flexible rope, and has high reliability and stability.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention and constitute a part of the application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations to the present invention. In the attached picture:

Fig. 1 is a side-view measurement schematic diagram of a shuttle-shaped sensor for real-time monitoring of the load and temperature of a flexible rope according to Embodiment 1 of the present invention.

Fig. 2 is a frontal measurement schematic diagram of a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to the first embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a shuttle-shaped sensor for real-time monitoring of the load and temperature of a flexible rope according to Embodiment 1 of the present invention.

Fig. 4 is a schematic top view of a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to the first embodiment of the present invention.

Fig. 5 is a top view of a cantilever beam of equal strength for a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to Embodiment 1 of the present invention.

Fig. 6 is a schematic diagram of a fiber grating and a separation sleeve sleeve connection method of a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to the first embodiment of the present invention.

Fig. 7 is a schematic diagram of a supporting column in a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to the second embodiment of the present invention.

Fig. 8 is a schematic diagram of a clamping method of a flexible rope in a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to the second embodiment of the present invention.

Fig. 9 is a schematic front view of another support column in a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to the second embodiment of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings, but it is not intended to limit the present invention.

As shown in Figures 1 and 2, it is a shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope described in Embodiment 1 of the present invention, including: a support unit, a bearing unit and a sensing unit, wherein,

The supporting unit includes: two arched structures 1a, 1b;

The carrying unit includes: an equal-strength cantilever beam 4 and a support column 5;

The sensing unit includes: a fiber grating 6 and a separation sleeve 9;

The sensor has a shuttle-shaped structure as a whole, which is composed of two arched 1a, 1b symmetrical structures. The two tips of the shuttle are thinner and thicker in the middle. The wider side is connected with an equal-strength cantilever beam 4; the position of the equal-strength cantilever beam 4 protruding away from the root is a support column 5, which is perpendicular to the plane of the equal-strength beam and is located at the center of the overall axial direction; The top of the support column is provided with a through hole 3, and the two tips of the shuttle are symmetrically provided with through holes 2a, 2b; the center of the upper and lower surfaces of the cantilever beam of equal strength is axially provided with grooves 8a, 8b near the root; wherein, A fiber grating 6 is pasted symmetrically in the two grooves 8a, 8b (as shown in Figures 3, 4 and 5);

A part of the grating region of the fiber grating is socketed with a separation sleeve 9 whose inner diameter is slightly larger than the diameter of the fiber grating. The portion 10a connected between the fiber grating and the separation sleeve is a temperature measurement unit, and the unsocketed portion 10b is a temperature measurement unit. The load unit, the fiber grating and the separation sleeve are fixed in the groove of the cantilever beam with equal strength by glue (502 glue) after being socketed, and then the fiber grating and the separation sleeve are potted with epoxy glue coated.

According to the sensor described in Embodiment 1 above, the distances between the supporting pillars 5 and the two through holes 2 a and 2 b are equal.

In addition, the two arches 1a, 1b, equal-strength cantilever beams 4 and support columns 5 are cut from an integral profile;

The cantilever beam 4 of equal strength is a simplified structure of an isosceles triangle, which is an isosceles trapezoid;

The fiber grating 6 is pasted and fixed on the upper and lower surfaces of the equal-strength cantilever beam 4 by using a simple single-grating separation and pasting technology, so as to realize simultaneous measurement of the load and temperature of the flexible rope;

Wherein, as shown in Figure 6, a part of the grating region of the fiber grating 6 is socketed with a separation sleeve 9 whose inner diameter is slightly larger than the diameter of the grating, and the separation sleeve 9 is a film sleeve with a thickness less than 100 μm, and then the entire said The grating region of the fiber grating 6 and the separation sleeve 9 are pasted and fixed in the groove in the middle of the cantilever beam 6 with equal strength. The part 10a where the optical fiber grating is connected to the separation sleeve is a temperature measurement unit, and the part 10b that is not connected is a load measurement unit.

Wherein, as shown in Figure 3, the diameters of the two tips of the shuttle shape of the sensor and the through holes 2a, 2b, 3 on the support column 5 are slightly larger than the diameter of the flexible rope measured; A certain smoothness requirement, the ratio of the distance from the through hole on the tip side of the shuttle to the support column 5 and the distance from the through hole to the through hole on the support column 5 is 1.08:1-2:1.

Here, based on the sensor described in the first embodiment above, the structure of the sensor is described in detail. The overall length of the sensor is 44 mm, the width is 27.6 mm, and the thickness is 5 mm. It consists of beams 4, support columns 5 and fiber gratings 6 on the upper and lower surfaces.

1 to 6, here is a detailed description, the manufacturing and packaging methods of the sensor are as follows:

First of all, the two arches 1a, 1b, equal-strength cantilever beams 4 and support columns 5 are all integral structures, which are formed by cutting and processing plates or blocks. Less parts, clean and beautiful. Made of elastic alloy materials, or other polymers, ceramics and other materials that meet the requirements of strength, stiffness and applicable temperature.

Secondly, the wider side of the tip of the shuttle-shaped stretches out (cuts out) a cantilever beam 4 of equal strength, and the position of the cantilever beam of equal strength away from the root protrudes as a support column 5, and the support column 5 is located at the center of the base axis , There is a curved seamless connection between the support column and the equal-strength cantilever beam. The root of the equal-strength cantilever beam is also chamfered to make the connection smooth. The width of the root of the equal-strength cantilever beam is smaller than the width of the connected side wall, reducing stress concentration and providing sufficient bearing capacity. A through hole 3 is drilled at a distance of 5.5mm from the top of the support column to the upper surface of the cantilever beam of equal strength, and through holes 2a and 2b are drilled symmetrically at the two tips of the shuttle.

Thirdly, the through holes 2a, 2b, 3 are all used for fixing and applying force to the flexible rope, and the diameters of the through holes are slightly larger than the diameter of the measured flexible rope. Moreover, they are all processed with chamfers and have a certain smoothness requirement to prevent damage to the flexible rope during measurement.

The 4th, the isosceles trapezoidal structure of the isosceles trapezoidal structure (two waist extension lines intersect to form isosceles triangle) of the isosceles cantilever beam 4 of sensor, 1a, 1b are all arch structures, can hold the double effect of load-bearing structure and enclosure structure concurrently, not only can It saves material, reduces self-weight, beautiful appearance, low loss and durability, and prevents the overall structure from being hooked to other flexible ropes in the working environment during use.

Fifth, the 4 roots of the equal-strength cantilever beam are connected to the side wall on the wider side of the tip of the shuttle-shaped structure, and this side wall can also be reinforced by other means to provide sufficient bearing capacity when the beam is bent. Grooves 8a, 8b are axially engraved on the center of the upper and lower surfaces of the equal-strength cantilever beam 4 for symmetrically fixing the fiber grating 6 and protecting the fiber grating (as shown in FIG. 5 ). The cantilever beam 4 of the sensor makes the bending stress of each section the same, which can avoid the strict requirements on the specific position when pasting and fixing the sensing fiber grating, reduces the possibility of the sensing fiber grating chirping, and reduces the difficulty of packaging. At the same time, it saves materials, maximizes the utilization rate of materials, improves the bearing capacity of the structure, makes the structure safer, saves space, reduces dead weight, and improves the usability of the structure.

Sixth, the fiber gratings 6 on the upper and lower surfaces adopt a simple single grating separation and pasting technology, and both the upper and lower fiber gratings 6 can realize dual-parameter sensing and measurement of load temperature. The fiber grating is socketed with a separation sleeve 9, and the connection method is as shown in FIG. 6 . The separation sleeve 9 is made of PBT, PP, PC, PET, PVC or other materials that meet the required conditions. The separation sleeve is relatively soft, the thickness is less than 100 μm, and the inner diameter is slightly larger than the diameter of the grating area, and can be embedded in the grooves 8a, 8b middle. The breakaway sleeve is threaded through the end of the fiber without the FC connector. The grooves 8a and 8b in the middle of the equal-strength cantilever beam 4 are polished with a file, gauze, etc. to remove rust, scale, and dirt and meet the flatness requirements. Clean the grooves with cotton wool soaked in acetone to remove grease and dust and keep them clean. Coat a small amount of 502 in the groove, spread evenly and form a thin glue layer, then connect a part of the grating area of the fiber grating with the separation sleeve 9, apply prestress to the entire grating area, and the grating area together with the separation sleeve The tube is pasted in the groove. After the 502 glue is cured, use KD504 epoxy glue to potting and coating the entire grating area and the separation sleeve until the epoxy glue is completely cured. When the equal-strength cantilever beam is stressed, the grid area part 10a covered with the separation sleeve 9 is a temperature measuring unit, which is in a free state in the separation sleeve and is not affected by the strain of the equal-strength cantilever beam; the part 10b without the separation sleeve is a load-measuring unit , fixed on the surface of an equal-strength cantilever beam subjected to tension or compression. Then the whole fiber grating has two reflection peaks, realizing simultaneous measurement of load and temperature. When mixing epoxy glue, pay attention to mixing evenly and eliminating air bubbles. Epoxy coating can not only further fix and paste the fiber grating, but also protect the grating and prevent it from breaking under force. The optical fiber grating pasted and fixed on the upper and lower surfaces of the equal-strength cantilever beam 4 of the present invention is a germanium-doped optical fiber grating, and the two are connected in series and output from the same output port.

According to the description of above-mentioned embodiment and accompanying drawing, the working principle of the present invention is as follows:

The flexible cord 8 is passed sequentially through the through-holes 2a, 2b and 4 of the sensor. When the equal-strength cantilever beam is stressed, the grid area part 12a that is socketed with the separation sleeve 11 is not affected by the strain of the equal-strength cantilever beam in the separation sleeve, and only reflects the temperature change of the environment. The part without separation sleeve 12b is fixed on the equal-strength cantilever When the surface of the beam is stretched or compressed, the entire fiber grating 7 has two reflection peaks, which are the reflection peak λ ₁ of the temperature response and the reflection peak λ ₂ of the strain and temperature coupling response. The wavelength shift of the reflection peak of the first temperature response caused by temperature change is Δλ ₁ , given by the formula

$\mathrm{<span\; class="notranslate">\; \&Delta;T</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&xi;</span>}}\frac{{\mathrm{<span\; class="notranslate">\; \&Delta;\&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Changes in outside temperature can be calculated. Among them, P _e is the elastic-optic coefficient of the fiber material, α _f is the thermal expansion coefficient of the fiber, ξ is the thermo-optic coefficient of the fiber material, and ΔT is the temperature change. When the rope is loaded, the pressure of the flexible rope 8 on the support column 5 causes the equal-strength cantilever beam to bend under pressure, and the strain on the upper surface of the equal-strength cantilever beam is opposite to that of the lower surface, and the upper sensing optical fibers respectively fixed on the upper surface of the equal-strength cantilever beam The part of the grating 7a and the lower sensing fiber grating 7b on the lower surface without a separate sleeve (load cell) is under tension and one is under compression, and the characterization of the two sensing fiber gratings is coupled with strain and temperature The center wavelength shifts of the reflection peaks are the same, and the Δλ ₂ is read after the two are averaged. The purpose of averaging is to make the result more precise. From this the following formula is derived

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}\mathrm{<span\; class="notranslate">\; EI</span>}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; hL</span>}}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; \&xi;</span>}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; ]</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&xi;</span>}}<span\; class="notranslate">\; \}</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Delta;\&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}\mathrm{<span\; class="notranslate">\; sec</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

The change in load on the flexible rope is calculated from the above formula. Where α _s is the thermal expansion coefficient of the base material, and E and I are the Young's modulus and moment of inertia of the cantilever beam of equal strength, respectively. h is the thickness of the equal-strength cantilever beam, θ is the angle between the flexible rope between the through holes 4 and 2a in Fig. 1 and the support column 5, and F is the tension on the flexible rope, that is, the measured load.

As shown in Figures 7, 8 and 9, it is Embodiment 2 of the present invention:

On the basis of the first embodiment above, the upper and lower surface fiber gratings 6 in the second embodiment adopt a simple single grating separation and pasting technology, and both the upper and lower fiber gratings 6 can realize dual-parameter sensing and measurement of load temperature. The grooves 8a and 8b in the middle of the equal-strength cantilever beam 4 are polished with a file, gauze, etc. to remove rust, scale, and dirt and meet the flatness requirements. Clean the grooves with cotton wool soaked in acetone to remove grease and dust and keep them clean. A part of the groove is coated with polyethylene or polypropylene, fluoroplastics and other materials with low polarity and smoothness after curing to form a thin layer of coating, and then a coating is applied to the part of the groove that is not coated with the above material. Apply a small amount of 502 evenly to form a thin glue layer, then apply prestress to the entire grating area and paste the grating area in the groove. After the 502 glue is cured, use KD504 epoxy glue to fill the entire grating area Seal coating until the epoxy glue is fully cured. When the cantilever beam of equal strength is stressed, the part (temperature measuring unit) coated with polyethylene, polypropylene, fluoroplastic and other coatings in the grating area will not be fixed on the cantilever beam, and will be in a free state without being affected by equal strength. Influenced by the strain of the cantilever beam, the rest of the grating (load measuring unit) is fixed on the surface of the equal-strength cantilever beam and subjected to tension or compression, so the entire fiber grating has two reflection peaks, realizing simultaneous measurement of load and temperature. Epoxy glue coating can not only further fix and paste the fiber grating, but also protect the grating and prevent it from breaking due to force. The other components and the connection relationship of the components are the same as those in the first embodiment.

The difference between the second embodiment and the first embodiment is that (as shown in FIG. 7 ), the through hole 11 on the support column is provided with a curved groove towards the obliquely upward side. Flexible rope clamping mode (as shown in Figure 8), wherein the through hole 12 on the tip of the shuttle-shaped sensor has a curved groove to the side obliquely downward. On the premise of not affecting the structure of the stress point of the flexible rope, it is convenient to install and clamp the sensor on the flexible rope. The other components and the connection relationship of the components are the same as the schematic diagram of the clamping mode of the flexible rope in Embodiment 1.

As shown in FIG. 9 , another clamping method: the through hole 13 on the support column is slotted upward, and the through hole on the tip of the shuttle sensor is slotted sideways. On the premise of not affecting the structure of the stress point of the flexible rope, it is convenient to install and clamp the sensor on the flexible rope. The other components and the connection relationship of the components are the same as in Embodiment 1.

In summary, compared with the prior art, the shuttle-shaped sensor for real-time monitoring of flexible rope load and temperature of the present invention has the following advantages and outstanding effects:

1. The sensor as a whole is composed of two arched symmetrical structures, which are in the shape of a shuttle, and the arched top view is an isosceles trapezoid. The two tips of the fusiform are thinner and thicker in the middle, and the size of the two tips is narrower at one end and wider at the other end. The tip of the shuttle is wider and one end side wall is connected to a cantilever beam of equal strength. The position of the cantilever beam of equal strength away from the root protrudes as a support column. The support column is perpendicular to the base plane and is located in the center of the overall axial direction. The top of the support column is drilled. The sidewalls of the two pointed ends of the shuttle are drilled symmetrically. Grooves are axially engraved on the center of the upper and lower surfaces of the equal-strength cantilever beam near the root. The two arches, equal-strength cantilever beams and supporting columns are all integral structures.

2. Since the present invention is based on fiber gratings and is fixed in the groove of an equal-strength cantilever beam by adopting a simple single grating separation and pasting technology, the simultaneous measurement of the load and temperature of the flexible rope can be realized.

3. The sensor of the present invention is small in size, light in weight, simple in structure, easy to assemble and disassemble, low in cost, ingenious in design, beautiful in appearance, has little influence on the measured object, and is easy to package and operate. The fiber grating can be effectively protected, and the measurement It will not be hooked to other ropes in the working environment; it has high sensitivity, high precision, and is free from electromagnetic interference; it can simultaneously and real-time measure the load and temperature of the flexible rope, and has high reliability and stability.

At the same time, the sensors of the present invention can also be used in series to realize multi-point and networked measurement of the load and temperature of the flexible rope.

The invention converts the measurement of the tensile load when the flexible rope is working into the measurement of the pressure of the rope on the cantilever beam of equal strength of the sensor. When the flexible rope is loaded, the cantilever beam of equal strength bends, and the two sensing gratings fixed on it generate strain. Compared with the traditional electromagnetic tension tester, the sensitivity and accuracy are greatly improved, and the volume and weight are greatly reduced. The structure is simple and convenient, integrated, durable, low cost, ingenious design, beautiful appearance, easy to measure It won't snag on other ropes in the work environment while you're at it. Double gratings are packaged in the same sensor in series, and each grating adopts the simple single grating separation and pasting technology, which improves the precision, saves the transmission channel and can realize long-distance transmission at the same time. Simultaneous measurement, and effectively protect the grating, and at the same time have the characteristics of being free from electromagnetic interference, which greatly improves the reliability and stability of the fiber grating sensor.

In the present invention, because the load on the flexible rope is not directly proportional to the wavelength drift of the optical fiber grating, there is a certain functional relationship, so it is necessary to provide the user with the correction function curve and the correction function curve of the universal testing machine and the wavelength drift of the optical fiber grating before leaving the factory. The universal testing machine can be connected with the flexible rope to be measured by the device of the present invention, and an external force from 0 to the maximum range of the present invention is applied through the testing machine, and the device of the present invention is connected with the fiber grating demodulator at the same time, and the wavelength of the fiber grating is measured by demodulation For the drift amount, the obtained fiber Bragg grating wavelength drift amount corresponds to the applied external force, and the calibration curve of load-fiber Bragg grating wavelength drift amount can be obtained. By adopting a sensor encapsulated by a material with appropriate stiffness, the load and the wavelength shift of the fiber grating can be approximated to have a linear relationship.

Certainly, the present invention can also have other various embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.

Claims (7)

1. A shuttle sensor for monitoring flexible rope load and temperature in real time, comprising: a support unit, a bearing unit and a sensing unit, wherein, The supporting unit includes: a shuttle-shaped frame composed of two arched structures; The bearing unit includes: equal-strength cantilever beams and support columns; The sensing unit includes: a fiber grating and a separation sleeve; The outer frame of the sensor shuttle structure is composed of two arched symmetrical structures. The two tips of the outer frame of the shuttle structure are thinner and thicker in the middle. The wider side of the tip is connected to a cantilever beam of equal strength; the position of the cantilever beam of equal strength away from the root protrudes as a support column, and the support column is perpendicular to the plane of the cantilever beam of equal strength and is located at the center of the overall axial direction; the support The top of the column is provided with through holes, and the two tips of the outer frame of the shuttle-shaped structure are symmetrically provided with through holes; the center of the upper and lower surfaces of the equal-strength cantilever beam is axially provided with grooves near the root; wherein, the two grooves are symmetrical A sensor unit with simultaneous measurement of temperature and load is pasted; The fiber grating is pasted and fixed in the groove of the equal-strength cantilever beam by using a single-grating separation and pasting technology. 2 . The shuttle-shaped sensor for real-time monitoring of the load and temperature of the flexible rope according to claim 1 , wherein the distances between the supporting columns and the two through holes are equal. 3 . 3. The shuttle-shaped sensor for real-time monitoring of flexible rope load and temperature as claimed in claim 1, wherein said two arched, equal-strength cantilever beams and support columns are all cut from an integral structure. 4. The shuttle sensor for real-time monitoring of the load and temperature of the flexible rope according to claim 3, wherein the isosceles trapezoidal shape of the isosceles cantilever beam. 5. The shuttle-shaped sensor for real-time monitoring of flexible rope load and temperature as claimed in claim 1, wherein the single grating separation and pasting technology is further: a part of the grid area of the optical fiber grating and the inner diameter are slightly larger than the The separation sleeve with the diameter of the optical fiber grating is socketed, the sleeved part of the optical fiber grating and the separation sleeve is a temperature measurement unit, and the unsleeved part is a load measurement unit, and the fiber grating and the separation sleeve are connected by bonding The glue is completely pasted and fixed in the groove of the cantilever beam with equal strength, and then the fiber grating and the separation sleeve are potted and coated with epoxy glue. 6. the shuttle sensor of real-time monitoring flexible rope load and temperature as claimed in claim 1, is characterized in that, described separating sleeve is the thin film sleeve that thickness is less than 100 μ m, and its material adopts PBT, PP, PC, PET or PVC. 7. The shuttle-shaped sensor for real-time monitoring of flexible rope load and temperature as claimed in claim 1, characterized in that, the diameters of the two pointed ends of the shuttle of the sensor and the through holes on the support column are slightly larger than that of the flexible rope. Rope diameter.