Intelligent cable with built-in sensor and sensor packaging method

Abstract

The present invention discloses an intelligent cable with a built-in sensor and a sensor packaging method. The intelligent cable with a built-in sensor includes a cable, a substrate made of a metal material, and a sensor with a metalized surface. The outer shell of the end portion of the cable is peeled off to reveal the steel wire inside the cable. The substrate is welded and fixed to the steel wire, and the sensor is welded and fixed to the substrate. The measuring direction of the sensor is the same as the axial direction of the cable. After the surface of the sensor is metallized, the metallized sensor is welded to the substrate, and the substrate is welded to the steel wire, so that the sensor can be packaged in the cable, and finally the exposed part of the sensor, the substrate and the steel wire are anti-corrosive. Compared with the traditional bonding and mechanical connection methods, the above-mentioned intelligent cable with a built-in sensor and the sensor packaging method significantly increase the service life of the sensor and realize the full life monitoring of the cable status. At the same time, the structure of the steel wire itself is not destroyed, and the life of the cable is not reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent cables, and in particular to an intelligent cable with a built-in sensor and a sensor packaging method. Background Art

[0002] As the main load-bearing components of cable-supported bridge structures, the stay cables, main cables and slings are under high stress cyclic fatigue loads for a long time. They have small cross-sectional dimensions and are very sensitive to corrosion. Once the stay cables or slings are damaged and deteriorated due to insufficient durability and safety, the loss of the bridge's bearing capacity will lead to a serious collapse accident, causing adverse social impacts and huge economic losses. In order to ensure the safe operation of the bridge, it is necessary to carry out preventive maintenance and safety testing on the stay cables, main cables and slings of the cable-supported bridge.

[0003] Smart cable technology is a new technology that directly implants strain sensing elements (temperature, stress or vibration sensors) into the cable structure during the cable manufacturing process, giving the cable self-sensing capabilities. At present, bridge engineers from all over the world are paying attention to the research and application of smart cables for bridges. How to combine precise sensors with cables so that the sensors can survive the various manufacturing processes of the cables and accurately output sensing signals, thereby effectively ensuring the survival rate of the built-in sensors, is a major challenge in the research of smart cables.

[0004] Considering the various processes of cable manufacturing, there are two forms of embedding sensors into cables: overall laying method and local embedding method. The overall laying method is to encapsulate the sensor in an appropriate structural form and make it into a cable structure. It participates in various processes of cable manufacturing together with the steel wire, twists and anchors it with the steel wire, and obtains the overall deformation of the cable through the output of the sensor. The local embedding method is to embed the sensor in a local position in the cable, such as near the anchor end, to detect parameters such as cable force and temperature. However, for the traditional local embedding method, the sensor is generally directly bonded or mechanically connected to the steel wire, the sensor has a low lifespan, and the cable status cannot be monitored throughout its life. Summary of the invention

[0005] Based on this, it is necessary to provide an intelligent cable with built-in sensors and a sensor packaging method to address the problem that the traditional local implantation method has a low sensor life and cannot achieve full-life monitoring of the cable status.

[0006] A smart cable with built-in sensors, comprising:

[0007] A cable, the end portion of which is stripped of its outer covering to expose the steel wires within the cable;

[0008] A base made of metal material, fixed to the steel wire by welding; and

[0009] The sensor with metallized surface is welded and fixed on the substrate, and the measuring direction of the sensor is the same as the axial direction of the cable.

[0010] In one embodiment, the base is rectangular, and the base is bent into an arc along its short side, and the radius of the arc is the same as the radius of the steel wire.

[0011] In one of the embodiments, an inwardly protruding plug is provided on the end surface of the base, and the plug is inserted into the gap between the steel wire bundles.

[0012] In one embodiment, a flexible metal insert is further included. The metal insert is disposed in the gap between the steel wire bundles and deforms and extends along the gap between the steel wire bundles. The metal insert is located between the insert blocks at both ends of the base.

[0013] In one embodiment, a plurality of rows of welding holes are provided on the substrate, and the welding holes in each row are spaced apart along the axial direction of the cable, and at least one row of welding holes is arranged on both sides of the sensor.

[0014] In one of the embodiments, a positioning protrusion is provided on the outer surface of the base, and the positioning protrusion extends along the axial direction of the cable, and a positioning groove is provided on the surface of the sensor to cooperate with the positioning protrusion.

[0015] A sensor packaging method, using any one of the above-mentioned smart cables with built-in sensors, is characterized by comprising the following steps:

[0016] Perform surface metallization treatment on the sensor;

[0017] Welding the sensor to a substrate made of a metal material;

[0018] Make the measuring direction of the sensor the same as the axial direction of the cable, and then weld and fix the base to the exposed steel wire of the cable;

[0019] Provide corrosion protection for the exposed parts, substrate and steel wire of the sensor.

[0020] In one embodiment, the step of performing surface metallization treatment on the sensor is specifically:

[0021] The surface of the sensor is pretreated, and then chemical nickel is plated on the surface of the sensor.

[0022] In one embodiment, the steps of welding and fixing the base to the exposed steel wire of the cable are specifically:

[0023] Inserting a flexible metal insert into the gap of the steel wire bundle, and deforming and extending the metal insert along the gap of the steel wire bundle;

[0024] Align the plugs of the base with the gaps of the wire bundle, then fit the base to the wires, and fix the metal inserts between the plugs at both ends of the base;

[0025] The periphery of the base is welded to the steel wire, and then the base is fixed by spot welding through the welding holes.

[0026] In one embodiment, the step of welding and fixing the substrate to the steel wire is specifically as follows:

[0027] The substrate is fixed on the steel wire by welding using low temperature solder or a welding machine.

[0028] The above-mentioned smart cable with built-in sensors and sensor packaging method have at least the following advantages:

[0029] After the sensor surface is metallized, the metallized sensor is welded to the substrate, and the substrate is welded to the steel wire, so that the sensor can be encapsulated in the cable. Compared with the traditional bonding and mechanical connection methods, the sensor is not directly fixed to the steel wire, and the sensor is encapsulated without glue, and the welding fixation is stable, which can greatly improve the fatigue resistance and corrosion resistance of the sensor, significantly increase the service life of the sensor, and realize the full life monitoring of the cable status. At the same time, only part of the cable shell is stripped without destroying the structure of the steel wire itself, which will not reduce the life of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of a smart cable with a built-in sensor in one embodiment;

[0031] Figure 2 for Figure 1 Left view of the mid-base;

[0032] Figure 3 is a schematic structural diagram of a metal insert in one embodiment;

[0033] Figure 4 for Figure 3 Schematic diagram of the structure in which the metal insert is filled between the substrate and the steel wire bundle;

[0034] Figure 5 for Figure 1 A schematic diagram of a structure in which welding holes are opened on the surface of a middle substrate;

[0035] Figure 6 Flowchart of a sensor packaging method in one embodiment. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the invention is not limited by the specific implementation disclosed below.

[0037] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0039] See also Figure 1 In one embodiment, a smart cable with a built-in sensor includes a cable 12, a substrate 14 made of a metal material, and a sensor 16 with a metalized surface.

[0040] The cable 12 includes a steel wire rope and a casing, wherein the casing is sleeved outside the steel wire rope and is used to protect the steel wire rope. The outer casing is peeled off from the end portion of the cable 12 to reveal the steel wire inside the cable 12. In one embodiment, the outer casing is made of PE (Polyethylene pipe, polyethylene plastic).

[0041] The base 14 is made of metal material, and the base 14 is welded and fixed on the exposed steel wire of the cable 12. In one embodiment, the base 14 is a stainless steel plate or a nickel-based alloy plate. The base 14 is rectangular, and the long side of the base 14 is consistent with the axial direction of the cable 12. The base 14 is bent into an arc along its short side, and the radius of the curved arc of the base 14 is the same as the radius of the steel wire, so as to ensure that the base 14 fits the steel wire and ensures the stability of the base 14 after welding.

[0042] See also Figures 2 to 4In one embodiment, the end surface of the base 14 is provided with an inwardly protruding plug 142, which is flush with the end surface of the base 14, and extends along the radial direction of the base 14 to protrude from the inner wall of the base 14. The base 14 is provided with plugs 142 at both ends, and the shape of the plugs 142 is adapted to the gap between the steel wire bundles 122. When the base 14 is attached to the steel wire, the plugs 142 are inserted into the gap between the steel wire bundles 122, and the base 14 and the steel wire are engaged with each other. The gap between the periphery of the base 14 and the steel wire bundles 122 is small, which can avoid excessive melting of steel wire during welding and damage to the structure of the steel wire itself, and at the same time ensure the stability of the base 14 welded and fixed on the steel wire.

[0043] On the basis of the above-mentioned embodiment, further, the smart cable 12 with built-in sensor 16 also includes a flexible metal insert 18, and the metal insert 18 is arranged in the gap between the steel wire bundles 122. The flexible metal insert 18 can be deformed, so it can be deformed and extended along the gap between the steel wire bundles 122. After the metal insert 18 is arranged in the gap between the steel wire bundles 122, the surface of the metal insert 18 is tangent to the surface of the steel wire and is concentric. The metal insert 18 is located in the coverage area of ​​the base 14, and the metal insert 18 is fixed between the insert blocks 142 at both ends of the base 14. In one embodiment, the metal insert 18 can be made of iron metal, and the slender iron insert can be deformed and extended along the gap between the steel wire bundles 122 under the action of external force.

[0044] See also Figure 5 , the surface of the base 14 is provided with multiple rows of welding holes 144, and the welding holes 144 in each row are arranged at intervals along the axial direction of the cable 12. When the base 14 is welded and fixed to the steel wire, the periphery of the base 14 can be welded to the steel wire first to preliminarily fix the base 14, and then spot welding can be performed through the welding holes 144. During the spot welding process, the metal insert 18 can be melted, and the molten metal insert 18 fills the gap between the inner wall of the base 14 and the steel wire bundle 122, so as to achieve welding of the inner wall of the base 14 to the steel wire. The base 14 is welded to the steel wire through multiple welding points, and the surface of the base 14 is uniformly stressed, so that the stress and strain of the steel wire can be uniformly transferred to the base 14, thereby ensuring the accuracy of the monitoring data of the sensor 16.

[0045] After the surface of the sensor 16 is metallized, the sensor 16 is welded to the substrate 14, and the measuring direction of the sensor 16 is the same as the axial direction of the cable 12, so that the sensor 16 can monitor the state of the cable 12. The surface metallization treatment of the sensor 16 can be performed by plating a metal material on the surface of the sensor 16, such as plating a layer of metal by chemical plating.

[0046] In one embodiment, a positioning protrusion (not shown) is provided on the outer surface of the base 14, and the positioning protrusion extends along the axial direction of the cable 12. A positioning groove is provided on the surface of the sensor 16, and the positioning groove is plugged and matched with the positioning protrusion, which can ensure that the measurement direction of the sensor 16 is the same as the axial direction of the cable 12, and ensure the accuracy of the measurement of the sensor 16. In one embodiment, the sensor 16 is a fiber grating strain sensor. The positioning groove on the surface of the sensor 16 can be formed when the surface of the sensor 16 is metallized.

[0047] See also Figure 6 The present invention also provides a sensor packaging method. To implement the packaging method, the above-mentioned smart cable with built-in sensor is used. Specifically, the packaging method includes the following steps:

[0048] Step S110: performing surface metallization treatment on the sensor 16 .

[0049] The surface of the sensor 16 is metallized, and a metal material may be plated on the surface of the sensor 16. Specifically, the steps of metallizing the surface of the sensor 16 are as follows: pre-treating the surface of the sensor 16, and then chemically plating nickel on the surface of the sensor 16. Pre-treating the surface of the sensor 16 can improve the coating quality on the surface of the sensor 16. In one embodiment, the sensor 16 is a fiber grating strain sensor. The steps of pre-treating the surface of the sensor 16 are as follows: alkali washing, water washing, roughening, heat treatment, activation and degumming the surface of the sensor 16.

[0050] In one embodiment, before the above step S110, the above method also includes: after the cable 12 is extruded to form an outer shell, a wire dividing plate is installed, the end of the cable 12 is inserted into the sleeve of the anchor, and then the anchor is poured, and finally the outer shell of the cable 12 located in the sleeve is peeled off to expose the steel wire in the cable 12, so as to facilitate the subsequent packaging of the sensor 16.

[0051] Step S120: welding the sensor 16 to the substrate 14 made of metal material.

[0052] Specifically, the material of the substrate 14 is a stainless steel plate or a nickel-based alloy thin plate. The positioning groove of the sensor 16 is plugged into the positioning protrusion to realize the installation of the sensor 16 on the substrate 14, and the measurement direction of the sensor 16 can be the same as the long side direction of the substrate 14. After the sensor 16 is installed, both sides of the sensor 16 have at least one row of welding holes 144. In one embodiment, both sides of the sensor 16 have two rows of welding holes 144, and the two rows of welding holes 144 on the same side of the sensor 16 are staggered. Finally, the sensor 16 is welded to the substrate 14, so that the sensor 16 and the substrate 14 are fixed as a whole.

[0053] Step S130 : Make the measuring direction of the sensor 16 the same as the axial direction of the cable 12 , and then weld and fix the base 14 to the exposed steel wire of the cable 12 .

[0054] Specifically, the base 14 is rectangular, and the long side of the base 14 is consistent with the axial direction of the cable 12, so that the measuring direction of the sensor 16 is the same as the axial direction of the cable 12. The base 14 is bent into an arc along its short side, and the radius of the curved arc of the base 14 is the same as the radius of the steel wire, so as to ensure that the base 14 fits the steel wire and ensures the stability of the base 14 after welding. The base 14 can be welded to the steel wire by low-temperature solder welding, or directly welded by a welding machine.

[0055] In one embodiment, the steps of welding and fixing the base 14 to the exposed steel wire of the cable 12 are specifically as follows: insert the flexible metal insert 18 into the gap of the steel wire bundle 122, and deform and extend the metal insert 18 along the gap of the steel wire bundle 122. Align the insert block 142 at one end of the base 14 with the gap of the steel wire bundle 122, and then rotate the base 14 to fit the steel wire, the metal insert 18 is covered by the base 14, and the metal insert 18 is fixed between the insert blocks 142 at both ends of the base 14. Finally, the periphery of the base 14 is welded to the steel wire to preliminarily fix the base 14, and then the base 14 is fixed by spot welding through the welding hole 144. The base 14 is connected to the steel wire through multiple welding points, and the surface of the base 14 is evenly stressed, so that the stress and strain of the steel wire can be evenly transferred to the base 14, thereby ensuring the accuracy of the monitoring data of the sensor 16.

[0056] Step S140: Anti-corrosion treatment is performed on the exposed portion of the sensor 16, the substrate 14 and the steel wire.

[0057] Specifically, after welding between the base 14 and the steel wire of the cable 12, the packaging of the sensor 16 is completed, and then the exposed part of the sensor 16, the base 14 and the steel wire are anti-corrosive, which can prevent the sensor 16, the base 14 and the steel wire from being corroded and improve the service life of the sensor 16. In one embodiment, an anti-corrosion material such as butter can be coated on the exposed part of the sensor 16, the base 14 and the steel wire for anti-corrosion.

[0058] In one embodiment, after the above step S140, the above method further includes: pouring a sealing paste into the sleeve. After the sensor 16 is fixed to the steel wire, the subsequent operation of the cable 12 production can be carried out. Finally, the sealing paste is poured into the sleeve to protect the sensor 16 and the lead wire 162.

[0059] The above-mentioned intelligent cable with built-in sensors and sensor packaging method, after the sensor 16 is metallized, the metallized sensor 16 is welded to the substrate 14, and the substrate 14 is welded to the steel wire, so that the sensor 16 can be packaged in the cable 12. Compared with the traditional bonding and mechanical connection method, the sensor 16 is not directly fixed to the steel wire, and the sensor 16 is packaged without glue, and the welding fixation is stable, which can greatly improve the fatigue resistance and corrosion resistance of the sensor 16, significantly increase the service life of the sensor 16, and realize the full life monitoring of the cable 12 state. At the same time, only part of the outer shell of the cable 12 is stripped without destroying the structure of the steel wire itself, and the service life of the cable 12 will not be reduced. The substrate 14 is connected to the steel wire through multiple welding points, and the surface of the substrate 14 is evenly stressed, which can make the stress and strain of the steel wire evenly transferred to the substrate 14, thereby ensuring the accuracy of the monitoring data of the sensor 16.

[0060] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0061] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A smart cable with built-in sensors, characterized in that: include: A cable, the end portion of which is stripped of its outer covering to expose the steel wires within the cable; A substrate made of metal material, fixed by welding on the steel wire; and A sensor with a metalized surface, fixed on the substrate by welding, wherein the measuring direction of the sensor is the same as the axial direction of the cable; The end surface of the base is provided with an inwardly protruding plug block, and the plug block is inserted into the gap between the steel wire bundles; It also includes a flexible metal insert, which is arranged in the gap of the steel wire bundle and deforms and extends along the gap of the steel wire bundle, and the metal insert is located between the insert blocks at both ends of the base; The base is provided with multiple rows of welding holes, and the welding holes in each row are arranged at intervals along the axial direction of the cable, and at least one row of welding holes is arranged on both sides of the sensor; A positioning protrusion is provided on the outer surface of the base, and the positioning protrusion extends along the axial direction of the cable. A positioning groove matched with the positioning protrusion is provided on the surface of the sensor.

2. The smart cable with built-in sensors according to claim 1, characterized in that: The base is rectangular and is bent into an arc along its short side, and the radius of the arc is the same as the radius of the steel wire.

3. A sensor packaging method, using the smart cable with built-in sensor as claimed in any one of claims 1-2, characterized in that: The following steps are involved: Perform surface metallization on the sensor; Welding the sensor to a substrate made of a metal material; Make the measuring direction of the sensor the same as the axial direction of the cable, and then weld and fix the base to the exposed steel wire of the cable; Provide corrosion protection for the exposed parts, substrate and steel wire of the sensor.

4. The sensor packaging method according to claim 3, characterized in that: The steps of performing surface metallization treatment on the sensor are specifically as follows: The surface of the sensor is pretreated, and then chemical nickel is plated on the surface of the sensor.

5. The sensor packaging method according to claim 3, characterized in that: The specific steps for welding the base to the exposed steel wire of the cable are: Inserting a flexible metal insert into the gap of the steel wire bundle, and deforming and extending the metal insert along the gap of the steel wire bundle; Align the plugs of the base with the gaps of the wire bundle, then fit the base to the wires, and fix the metal inserts between the plugs at both ends of the base; The periphery of the base is welded to the steel wire, and then the base is fixed by spot welding through the welding holes.

6. The sensor packaging method according to claim 3, characterized in that: The steps of welding and fixing the substrate on the steel wire are specifically as follows: The substrate is fixed on the steel wire by welding using low temperature solder or a welding machine.

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