Force measuring anchor cable and preparation method

Abstract

The invention discloses a force measuring anchor cable and a preparation method. The force measuring anchor cable comprises an anchor cable body, a strain gauge, a protective sleeve and an integrated circuit board. A plurality of strain gauges are fixed on the outer surface of a middle wire at the force measuring end of the anchor cable body, each strain gauge is sleeved with a protective sleeve, a protective groove is formed in the middle wire of the anchor cable body, and wires of the plurality of strain gauges are placed in the protective groove and are in communication connection with the integrated circuit board. According to the force measuring anchor cable and the preparation method, the complexity of the preparation process can be simplified.

Description

Technical Field

[0001] The invention relates to the technical field of force measuring anchor cables, in particular to a force measuring anchor cable and a preparation method thereof. Background Art

[0002] With the increasing demand for energy and the continuous increase in mining intensity, shallow resources are decreasing, and the deformation process of deep surrounding rocks is more complicated than that of shallow ones. Moreover, most of the anchor cables as supporting materials are located in the deep surrounding rocks, and their activities are somewhat hidden. It is impossible to understand the stress of the anchor cables in the deep surrounding rocks, and it is impossible to make an accurate judgment on the degree of deformation of the surrounding rocks and realize the stability control of the surrounding rocks.

[0003] In the prior art, the invention patent with the patent publication number CN114778269A discloses an intelligent anchor and a monitoring method thereof, wherein the intelligent anchor is used to obtain its own initial test value, wherein when the intelligent anchor is an anchor rod, the strain gauge is arranged in the installation groove opened on the anchor rod body, and when the intelligent anchor is an anchor cable, the strain gauge is arranged in the middle wire of the steel wire, and the middle wire is a hollow structure. When the intelligent anchor is subjected to force, the strain gauge will stretch or shrink as the rod body deforms, thereby changing the resistance value, causing the output voltage to change, and reacting to the strain size of the strain gauge. When the axial load acting on the anchor cable rod body is too large, the rod body will bend, and the strain gauge at the measuring point will deform as the rod body deforms, thereby causing a voltage change, reacting to the bending deformation of the anchor cable rod body, and the strain gauge deforms with the anchor cable rod body, realizing the monitoring of the parameters such as the axial force and bending force of the anchor cable, and then judging the degree of deformation of the surrounding rock, so as to realize the control of the stability of the surrounding rock.

[0004] However, in actual use, the length of the force measuring anchor is 50 meters. When the smart anchor is an anchor rod, the strain gauge is set in the anchor rod, and the measuring points need to be evenly set. Specific tools are required to install the strain gauge in the anchor rod. Secondly, when the smart anchor is an anchor cable, it is also very difficult to achieve. The diameter of the middle wire is generally only 7-8mm. It is very difficult to place a strain gauge with such a small diameter. In summary, the existing force measuring anchor is difficult to manufacture and is not easy to promote. Summary of the invention

[0005] The technical problem to be solved by the present invention is to solve the problem that the existing force measuring anchor is difficult to manufacture and inconvenient to promote and use.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A force measuring anchor cable comprises: an anchor cable body (100), a strain gauge (200), a protective cover (300) and an integrated circuit board (400); a plurality of strain gauges (200) are fixed on the outer surface of a middle wire (110) at a force measuring end of the anchor cable body (100), and each strain gauge (200) is sleeved with a protective cover (300); a protective groove is provided on the middle wire (110) of the anchor cable body (100), and the wires of the plurality of strain gauges (200) are placed in the protective groove and are communicatively connected with the integrated circuit board (400).

[0008] Advantages: Based on the characteristics that the strain gauge will stretch or shrink as the anchor cable deforms, thereby changing the resistance value and causing the output voltage to change, the full bridge arrangement is used based on the Wheatstone bridge balance principle, and the measurement accuracy is doubled. By directly pasting the strain gauge on the surface of the anchor cable, the preparation process of the force measuring anchor cable is greatly optimized. After the anchor cable is supported, the stress condition of the deep rock formation can be directly monitored. There are several strain gauges distributed on one anchor cable, which greatly expands the monitoring range.

[0009] In one embodiment of the present invention, the protective cover (300) includes a first end (310), a middle section (320) and a second end (330) which are connected in sequence, and the first end (310), the middle section (320) and the second end (330) are internally connected.

[0010] In one embodiment of the present invention, the outer diameters of the first end portion (310) and the second end portion (330) are equal and are both larger than the outer diameter of the middle section (320).

[0011] In one embodiment of the present invention, the protective cover (300) has an appearance of an “I” shape.

[0012] In one embodiment of the present invention, the inner diameters of the first end portion (310) and the second end portion (330) are equal and are both smaller than the inner diameter of the middle section (320).

[0013] In one embodiment of the present invention, the inner diameters of the first end portion (310) and the second end portion (330) are greater than the diameter of the middle wire (110) of the anchor cable body (100).

[0014] In one embodiment of the present invention, the strain gauge (200) is located in the middle section (320).

[0015] In one embodiment of the present invention, the diameter of the force measuring anchor cable is smaller than the diameter of the force measuring mounting hole (A).

[0016] The present invention also discloses a method for preparing a force measuring anchor cable, comprising:

[0017] Stock Split:

[0018] The anchor cable body (100) is split into strands, and the middle wire (110) in the middle of the anchor cable body (100) is taken out;

[0019] Grooving:

[0020] Carving the protective groove on the middle wire (110) of the anchor cable body (100);

[0021] Grinding and cleaning:

[0022] The surface of the middle wire (110) is cleaned with a cleaning agent, and the fixed position of the strain gauge (200) is marked and polished; the strain gauge is fixed:

[0023] After the fixed position of the strain gauge (200) is polished and cleaned, an adhesive is prepared and applied to the back of the strain gauge (200), and the strain gauge (200) is directly attached to the marked position on the surface of the anchor cable middle wire (110);

[0024] The installation foot of the strain gauge (200) is connected to the integrated circuit board (400) by extending the connecting wire; all the wires of the strain gauge (200) are placed in the protection groove, and the strain gauge (200) is tested to see if it is intact. If there is no damage, the wires of the strain gauge (200) are potted in the protection groove by potting glue;

[0025] The protective cover (300) is sleeved on the strain gauge (200) to complete the preparation of the middle wire (110) of the anchor cable body (100).

[0026] In one embodiment of the present invention, the preparation method further comprises: winding the middle wire (110) of the prepared anchor cable body (100) with other steel strands, and providing a tail sleeve (700) at the non-force measuring end tail sleeve of the anchor cable body (100), and fixing it to the anchor cable body (100).

[0027] Compared with the prior art, the invention has the following beneficial effects: a through groove is engraved on the anchor cable wire, and the wire is routed through the groove, which solves the problem that the wire is easily broken and the integrated circuit board cannot receive information. The strain gauge is directly pasted on the surface of the anchor cable wire, which simplifies the complexity of the preparation process. The strain gauge can be prevented from being damaged by a special protective cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of a force measuring anchor cable according to an embodiment of the present invention.

[0029] Figure 2 Schematic diagram of a protective cover according to an embodiment of the present invention.

[0030] Figure 3 Schematic diagram of information transmission route according to an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to facilitate those skilled in the art to understand the technical solution of the present invention, the technical solution of the present invention is further described in conjunction with the accompanying drawings of the specification.

[0032] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0033] See also Figure 1 and Figure 2 As shown, the present invention provides a force measuring anchor cable, comprising: an anchor cable body 100, a strain gauge 200, a protective cover 300 and an integrated circuit board 400. A plurality of strain gauges 200 are fixed on the outer surface of the middle wire 110 of the force measuring end of the anchor cable body 100, and a protective cover 300 is sleeved on each strain gauge 200, and a protective groove is provided on the middle wire 110 of the anchor cable body 100, and the wires of the plurality of strain gauges 200 are placed in the protective groove and are connected to the integrated circuit board 400 for communication.

[0034] In one embodiment of the present invention, the strain gauge 200 is a resistive strain gauge optical fiber, which is adhered and fixed on the outer surface of the middle wire 110 by a distributed step method, and is connected to the integrated circuit board 400 through a wire to realize information transmission.

[0035] By notching the middle wire 110 , the wire of the strain gauge 200 is placed in the protective groove, so as to ensure that the wire will not be broken, thereby causing the integrated circuit board 400 to fail to receive information.

[0036] In one embodiment of the present invention, the protective cover 300 includes a first end 310, a middle section 320, and a second end 330 connected in sequence, and the first end 310, the middle section 320, and the second end 330 are internally connected, and the strain gauge 200 is located in the middle section 320. Among them, the outer diameters of the first end 310 and the second end 330 are equal, and both are larger than the outer diameter of the middle section 320, that is, the pressure is supported in the form of thick ends and thin middle, so that the strain gauge 200 is protected from being crushed. Specifically, the shape of the protective cover 300 is in the shape of an "I". The inner diameters of the first end 310 and the second end 330 are equal and smaller than the inner diameter of the middle section 320, so as to provide space for the strain gauge 200, and prevent the protective cover 300 from pressing the strain gauge 200, so that the strain gauge 200 does not measure accurately. The inner diameters of the first end 310 and the second end 330 are small, so as to prevent the protective cover 300 from shaking. The inner diameters of the first end 310 and the second end 330 are larger than the diameter of the middle wire 110 of the anchor cable body 100. Preferably, the inner diameters of the first end 310 and the second end 330 are equal to the diameter of the middle wire 110, or slightly larger than the diameter of the middle wire 110. In addition, the diameter of the force measuring anchor cable is smaller than the diameter of the force measuring installation hole A. In fact, each anchor cable has its own model, and each model of anchor cable has a corresponding force measuring installation hole A diameter requirement. For example, the anchor cable with a diameter of 22 mm corresponds to a force measuring installation hole A with a diameter of 32 mm. However, the present invention adheres a strain gauge 200 to the middle wire 110 of the anchor cable body 100, and sets a protective cover 300 on the strain gauge 200, thereby increasing the diameter of the anchor cable body 100. In order to prevent the force measuring anchor cable from being unable to be inserted into the force measuring installation hole A, it is necessary to ensure that the diameter of the force measuring anchor cable is smaller than the diameter of the force measuring installation hole (A).

[0037] In this embodiment, the integrated circuit board 400 is, for example, a strain gauge, and the strain gauge 200 is a foil type, which can form a full-bridge Wheatstone circuit.

[0038] See also Figure 1 and Figure 2 As shown, in one embodiment of the invention, the force measuring anchor cable further comprises a self-aligning ball pad 500, an anchor cable lock 600, a tail sleeve 700 and a navigation plug 800. The self-aligning ball pad 500 and the anchor cable lock 600 are sequentially sleeved on the non-force measuring end of the anchor cable body 100, the self-aligning ball pad 500 is used to make the anchor cable body 100 perpendicular to the force measuring surface B, and the anchor cable lock 600 regulates the stretching direction of the anchor cable body 100 when stretched, so as to better bear the force.

[0039] The tail sleeve 700 is fixed at the tail of the non-force-measuring end of the anchor cable body 100, and the integrated circuit board 400 is fixed in the tail sleeve 700, and the integrated circuit board 400 is connected to the aviation plug 800. The aviation plug 800 is fixed at the outside of the tail sleeve 700. Specifically, the tail sleeve 700 and the tail of the non-force-measuring end of the anchor cable body 100 are potted with potting glue, the aviation plug 800 is connected to the outside, and the integrated circuit board 400 is inside the tail sleeve 700, which has the effect of preventing moisture and dust from invading the inside of the tail sleeve 700 and protecting the integrated circuit board 400.

[0040] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the working principle of the force measuring anchor cable is based on the strain measurement principle and sensor technology. The strain response of the anchor cable is measured according to the corresponding deformation caused by the change of the force on the anchor cable body 100, and the strain gauge 200 is installed on the surface of the middle wire of the anchor cable body 100, and the strain signal on the surface of the middle wire is measured by the strain gauge 200 to reflect the strain response of the anchor cable body 100.

[0041] The process of information transmission is: first collect the original data of the strain gauge 200, and analyze and measure the external force conditions through the characteristics that the strain gauge 200 will stretch or shrink as the anchor body 100 deforms, thereby changing the resistance value and causing the output voltage to change.

[0042] See also Figures 1 to 3 As shown, in one embodiment of the present invention, the force information obtained by the integrated circuit board 400 can also be transmitted to the transmission substation 910, the intelligent gateway 920 and the cloud platform 930. When the force measuring anchor cable is stressed, the integrated circuit board 400 collects the force information, and converts the analog voltage signal into a digital signal, and transmits it to the transmission substation 910. The transmission substation 910 performs data acquisition control and data collection on multiple integrated circuit boards 400, and then passes through the intelligent gateway 920 to further achieve regular inspection, data collection, and data storage, and uploads data and parameter configuration information to the cloud platform 930 in real time through Ethernet to achieve remote real-time dynamic monitoring.

[0043] See also Figures 1 to 3 As shown, the present invention also provides a method for preparing a force measuring anchor cable, comprising:

[0044] Stock Split:

[0045] The anchor cable body 100 is split into strands, and the middle wire 110 in the middle of the anchor cable body 100 is taken out. In this embodiment, a 6.3-meter-long ordinary anchor cable is placed in a splitting tool, and the middle wire in the middle of the anchor cable is taken out.

[0046] Grooving:

[0047] The protective groove is engraved on the middle wire 110 of the anchor cable body 100. In this embodiment, the middle wire is engraved with a groove to allow the wire to pass through the groove, which can effectively prevent the wire from being crushed and causing the integrated circuit board 400 to fail to receive data.

[0048] Grinding and cleaning:

[0049] Clean the surface of the middle wire 110 with a cleaning agent, and mark and polish the fixed position of the strain gauge 200;

[0050] The strain gauge is fixed. In this embodiment, acetone is used to clean the surface of the middle wire 110, the grinding position is marked, and the polishing and surface treatment area is 3 to 5 times the area of ​​the strain gauge 200 to remove oil stains, rust spots, oxide films, etc. to prevent the strain gauge 200 from insufficiently contacting the middle wire 110 and causing errors.

[0051] After the fixed position of the strain gauge 200 is polished and cleaned, an adhesive is prepared and applied to the back of the strain gauge 200, and the strain gauge 200 is directly pasted on the marked position on the surface of the anchor cable middle wire 110. In this embodiment, after polishing and cleaning, glue is prepared and applied to the back of the strain gauge 200 with a glue pen, and the strain gauge 200 is directly pasted on the marked position on the surface of the middle wire 110. For protective measures, polytetrafluoroethylene film and rubber are used to fix the strain gauge 200, and a special clamp for force measuring anchor cable is used to fix the strain gauge 200.

[0052] The mounting foot of the strain gauge 200 is connected to the integrated circuit board 400 by extending the connecting wire; all the wires of the strain gauge 200 are placed in the protection groove, and the strain gauge 200 is tested to be intact. After there is no damage, the wires of the strain gauge 200 are potted in the protection groove by potting glue. In this embodiment, the mounting foot of the strain gauge 200 is connected to the integrated circuit board 400 by extending the connecting wire using an electric welder. All the wires are placed in the protection groove, and the strain gauge 200 is tested to be intact. After there is no damage, the prepared potting glue is used to pot all the protection grooves.

[0053] The protective cover 300 is put on the strain gauge 200 to complete the preparation of the middle wire 110 of the anchor cable body 100. In this embodiment, the protective cover 300 is put on the strain gauge 200 to effectively ensure that the strain gauge 200 will not be directly damaged and fail after the force measuring anchor cable is subjected to force.

[0054] The prepared middle wire 110 of the anchor cable body 100 is wound around other steel strands, and a tail sleeve 700 is provided at the non-force measuring end of the anchor cable body 100 and fixedly connected to the anchor cable body 100. In this embodiment, the prepared middle wire 110 is wound around other steel strands of the anchor cable body 100, for example, by screwing the middle wire 110 and other steel strands at the two ends of the anchor cable body 100 with different motors. The tail sleeve 700 is potted at the non-force measuring end of the anchor cable body 100 with a prepared potting glue, which prevents moisture and dust from invading the inside of the sleeve and protects the integrated circuit board 400.

[0055] In one embodiment of the present invention, when the force measuring anchor cable is used for force measurement, the force measuring anchor cable is placed in a calibration tool to simulate the effect of the rock wall, and an anchor cable puller (which is the same as an ordinary puller, equivalent to adding a clamp to simulate the situation of the force measuring anchor cable in the surrounding rock) is used to apply different loads and collect data of the strain gauge 200, and the force measuring anchor cable is automatically calibrated using calibration software. Placing the strain gauge 200 in the anchor cable puller is equivalent to fixing the anchor cable with a clamp, and applying tension through the puller to simulate the stress change of the surrounding rock.

[0056] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

[0057] The above-described embodiments merely represent implementation methods of the invention. The protection scope of the present invention is not limited to the above-described embodiments. For those skilled in the art, several modifications and improvements may be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A force measuring anchor cable, characterized in that: Comprising: A cable anchor body (100), a strain gauge (200), a protective sleeve (300), and an integrated circuit board (400); a plurality of strain gauges (200) are fixed on the outer surface of the middle wire (110) at the force-measuring end of the cable anchor body (100), and a protective sleeve (300) is sleeved on each strain gauge (200), and a protective groove is provided on the middle wire (110) of the cable anchor body (100), and the wires of the plurality of strain gauges (200) are placed in the protective groove and are communicatively connected to the integrated circuit board (400).

2. The force measuring anchor cable according to claim 1, characterized in that: The protective sleeve (300) includes a first end portion (310), a middle section (320), and a second end portion (330) that are connected in sequence, and the interiors of the first end portion (310), the middle section (320), and the second end portion (330) are in communication.

3. The force measuring anchor cable according to claim 2, characterized in that: The outer diameters of the first end portion (310) and the second end portion (330) are equal and are both larger than the outer diameter of the middle section (320).

4. The force measuring anchor cable according to claim 2, characterized in that: The outer shape of the protective sleeve (300) is in the shape of a "工" character.

5. The force measuring anchor cable according to claim 2, characterized in that: The inner diameters of the first end portion (310) and the second end portion (330) are equal and are both smaller than the inner diameter of the middle section (320).

6. The force measuring anchor cable according to claim 5, characterized in that: The inner diameters of the first end portion (310) and the second end portion (330) are larger than the diameter of the middle wire (110) of the cable anchor body (100).

7. The force measuring anchor cable according to claim 5, characterized in that: The strain gauge (200) is located inside the middle section (320).

8. The force measuring anchor cable according to claim 1, characterized in that: The diameter of the force-measuring cable anchor is smaller than the diameter of the force-measuring installation hole (A).

9. A method for preparing a force measuring anchor cable according to any one of claims 1 to 8, characterized in that: Comprising: Strand separation: Perform strand separation on the cable anchor body (100) and take out the middle wire (110) inside the cable anchor body (100); Grooving: Cut the protective groove on the middle wire (110) of the cable anchor body (100); Grinding and cleaning: Clean the surface of the middle wire (110) with a cleaning agent, and mark and polish the fixed position of the strain gauge (200); Strain gauge fixing: After grinding and cleaning the fixed position of the strain gauge (200), prepare the adhesive, apply it to the back of the strain gauge (200), and directly paste the strain gauge (200) on the marked position on the surface of the middle wire (110) of the cable anchor; Connect the mounting feet of the strain gauge (200) to the integrated circuit board (400) by extending the connecting wires; put all the wires of the strain gauge (200) into the protective groove, and detect whether the strain gauge (200) is intact. After there is no damage, pot the wires of the strain gauge (200) in the protective groove with potting glue; Put the protective sleeve (300) on the strain gauge (200) to complete the preparation of the middle wire (110) of the cable anchor body (100).

10. The method for preparing a force measuring anchor cable according to claim 9, characterized in that: The preparation method further includes: winding the middle wire (110) of the cable anchor body (100) that has been prepared with other steel strands, and sleeving a tail sleeve (700) on the non-force-measuring end of the cable anchor body (100) and fixedly connecting it to the cable anchor body (100).

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