Stress sensor
By independently setting excitation and induction coils on the elevator wire rope, the saturation magnetization of the elevator wire rope is achieved by using the U-shaped magnetic core, the problem of low measurement accuracy caused by magnetic field attenuation in the prior art is solved, and the accuracy of axial stress measurement of the elevator wire rope is improved and security.
Patent Information
- Application Number
- CN202421138649.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-23
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2034-05-23
AI Technical Summary
The existing axial stress measurement method for elevator wire ropes is directly wound on the wire rope, resulting in magnetic field attenuation, reducing the measurement accuracy, and thus affecting the safety of the elevator.
Using stress sensors including coil bearing part, U-shaped magnetic core part, excitation coil and induction coil, the excitation coil and induction coil are independently arranged on the U-shaped magnetic core part, and the excitation coil generates an excitation magnetic field to make the elevator wire rope saturated magnetization and avoid magnetic fields. Attenuation, improve measurement accuracy.
By independently setting the excitation and induction coils, the magnetic field attenuation is avoided, the accuracy of stress measurement and the safety of elevator operation are improved, and the on-site installation and maintenance are facilitated.
Smart Images
Figure CN222231923U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of electromagnetic technology, and in particular to a stress sensor. Background Art
[0002] Wire rope (also known as steel cable, steel strand) is a flexible load-bearing component with good tensile strength, high fatigue strength and strong impact resistance. It is the main force-bearing and force-transmitting component of elevators, lifting equipment and other equipment. The uneven force or failure of elevator wire ropes due to corrosion, overload, torsion, fatigue and defects can easily cause safety accidents such as slipping, accidental movement of the car, top and bottom collisions, posing a huge threat to the safety of passengers. The axial stress state of the elevator wire rope plays a vital role in the assessment of the safety and health status of the elevator. Therefore, monitoring the axial stress of the elevator wire rope is of great significance to ensure the safe operation of the elevator.
[0003] The existing methods for measuring the axial stress of elevator wire ropes mainly include pressure sensor method, strain monitoring method, vibration frequency method, etc. Among them, the pressure sensor method mainly involves winding the excitation coil and the induction coil on the elevator wire rope to be measured. The magnetic field generated by the excitation coil based on the excitation current is a uniform magnetic field. The elevator wire rope is in the magnetic field, and when subjected to axial stress, the internal magnetic induction intensity changes, causing the output voltage of the induction coil to change. The axial stress of the elevator wire rope is measured through the voltage change.
[0004] However, since the excitation coil and the induction coil are directly wound around the elevator wire rope, when the excitation magnetic field generated by the excitation coil causes the elevator wire rope to reach saturation magnetization, the air gap or interval between the elevator wire rope and the induction coil will cause the magnetic field to attenuate, reducing the accuracy of the elevator wire rope stress measurement and thereby reducing the safety of the elevator operation. Utility Model Content
[0005] The purpose of the embodiments of the present application is to provide a stress sensor to solve the problem of low accuracy in measuring the axial stress of existing elevator wire ropes.
[0006] In order to solve the above technical problems, this specification is implemented as follows:
[0007] In a first aspect, a stress sensor is provided, comprising:
[0008] A coil bearing portion, wherein the coil bearing portion forms a through hole, and the elevator wire rope is movably arranged in the through hole along the axis direction of the through hole;
[0009] A U-shaped magnetic core portion, arranged on the coil bearing portion;
[0010] An excitation coil, disposed on the U-shaped magnetic core portion, the excitation coil receiving an excitation current to generate an excitation magnetic field;
[0011] The induction coil is arranged on the U-shaped magnetic core part, and the induction coil outputs an induced voltage signal.
[0012] Optionally, the U-shaped magnetic core portion includes a first magnetic core portion and a second magnetic core portion parallel to each other, and a third magnetic core portion having two ends respectively connected to the first magnetic core portion and the second magnetic core portion, a first end of the first magnetic core portion and a first end of the second magnetic core portion are respectively connected to the coil bearing portion, and a second end of the first magnetic core portion and a second end of the second magnetic core portion are respectively connected to two ends of the third magnetic core portion;
[0013] The first magnetic core portion and the second magnetic core portion are respectively perpendicular to a first plane where the axis is located, and a projection of the third magnetic core portion on the first plane forms a preset angle with the axis.
[0014] Optionally, there is one U-shaped magnetic core portion, which is arranged on one side of the coil bearing portion.
[0015] Optionally, the preset angle is 0.
[0016] Optionally, the excitation coil is arranged on the first magnetic core portion of the U-shaped magnetic core portion, and the induction coil is arranged on the second magnetic core portion of the U-shaped magnetic core portion.
[0017] Optionally, there are two U-shaped magnetic core parts, which are respectively arranged on a first side and a second side opposite to the coil bearing part.
[0018] Optionally, the preset angle is not 0.
[0019] Optionally, the excitation coil is arranged on the third magnetic core portion on the first side, and the induction coil is arranged on the third magnetic core portion on the second side.
[0020] Optionally, a preset angle formed by the third magnetic core portion on the first side and the axis is 45 degrees, and a preset angle formed by the third magnetic core portion on the second side and the axis is 135 degrees.
[0021] Optionally, the U-shaped magnetic core portion includes a silicon steel magnetic core or a soft ferrite magnetic core.
[0022] In an embodiment of the present application, the stress sensor includes a coil bearing portion, a U-shaped magnetic core portion, an excitation coil and an induction coil, and the U-shaped magnetic core portion is arranged on the coil bearing portion, the excitation coil is arranged on the U-shaped magnetic core portion to receive an excitation current to generate an excitation magnetic field, and the induction coil is arranged on the U-shaped magnetic core portion to output an induced voltage signal, whereby the excitation coil and the induction coil are independently wound from the elevator wire rope. When the excitation magnetic field generated by the excitation coil causes the elevator wire rope to reach saturation magnetization, the influence of magnetic field attenuation between the elevator wire rope and the induction coil can be avoided, thereby ensuring the accuracy of stress measurement, improving the safety of elevator operation, and facilitating on-site installation and maintenance of the stress sensor without disassembling the elevator wire rope. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0024] Figure 1 It is a schematic structural diagram of the stress sensor of the first embodiment of the present application.
[0025] Figure 2 It is a schematic diagram of the three-dimensional structure of the stress sensor according to the second embodiment of the present application.
[0026] Figure 3 4 is a side view of the coil bearing portion of the stress sensor according to the second embodiment of the present application.
[0027] Figure 4 FIG. 4 is a top view of a U-shaped magnetic core portion of a stress sensor according to a second embodiment of the present application.
[0028] Figure 5 4 is a front view of a U-shaped magnetic core portion of a stress sensor according to a second embodiment of the present application. DETAILED DESCRIPTION
[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application. The numbering of the drawings in this application is only used to distinguish the various steps in the scheme, and is not used to limit the execution order of the various steps. The specific execution order is subject to the description in the specification.
[0030] In order to solve the problems existing in the prior art, Figure 1 and Figure 2The embodiment of the present application provides a stress sensor, including: a coil bearing part 20, the coil bearing part 20 forms a through hole 30, and an elevator wire rope 40 is movably inserted into the through hole 30 along the direction of the axis A of the through hole 30; a U-shaped magnetic core part 70, which is arranged on the coil bearing part 20; an excitation coil 50, which is arranged on the U-shaped magnetic core part 70, and the excitation coil 50 receives an excitation current to generate an excitation magnetic field; an induction coil 60, which is arranged on the U-shaped magnetic core part 70, and the induction coil 60 outputs an induced voltage signal.
[0031] In the embodiment of the present application, the elevator wire rope 40 passes through the coil bearing part 20 through the through hole 30, and the coil bearing part 20 is provided with a U-shaped magnetic core part 70 wound with an excitation coil 50 and an induction coil 60, so that the excitation coil 50 and the induction coil 60 are arranged adjacent to the elevator wire rope 40. The excitation coil 50 is used to generate an excitation magnetic field through an excitation current, and the induction coil 60 is used to generate an induced voltage signal according to the elevator wire rope 40 magnetized by the excitation magnetic field.
[0032] The signal generation and detection system 100 is connected to a computer, and a control signal is sent to the signal generator in the signal generation and detection system 100 through the computer to generate an AC excitation current and provide it to the excitation coil 50. The excitation magnetic field generated by the excitation current is a uniform excitation magnetic field that can make the elevator wire rope 40 reach saturation magnetization. Saturation magnetization refers to the maximum magnetization intensity that the elevator wire rope 40 can reach when it is magnetized in an external excitation magnetic field. After the elevator wire rope 40 reaches saturation magnetization, the magnetic attraction of the elevator wire rope 40 will not increase with the increase of the excitation magnetic field intensity. A uniform excitation magnetic field refers to a magnetic field with a constant magnetic field intensity. The uniform excitation magnetic field is an AC periodic excitation magnetic field, and correspondingly, the elevator wire rope 40 can periodically reach saturation magnetization.
[0033] The elevator wire rope 40 is a ferromagnetic material with high magnetic permeability. When placed in an external magnetic field of a certain intensity, it can be strongly magnetized and exhibit strong magnetism. When the elevator wire rope 40 is in a uniform magnetic field and subjected to axial stress, changes in elastic energy occur inside it, causing its magnetization intensity to reorient, resulting in a change in magnetic permeability. Changes in magnetic permeability will produce an equivalent magnetic field. The existence of an equivalent magnetic field causes changes in the magnetic induction intensity inside the elevator wire rope, and thus the output voltage at both ends of the induction coil also changes. Changes in magnetic induction intensity can be reflected by the induced voltage, that is, there is a corresponding relationship between the axial stress on the elevator wire rope and the induced voltage.
[0034] The detector in the signal generation and detection system 100, such as a data acquisition card, collects the induced voltage signal output by the induction coil 60 and saves it on the computer. The induced voltage signal output by the induction coil 60 can be used to measure the axial stress of the elevator wire rope 40.
[0035] Combination Figure 1 and Figure 2 Optionally, in an embodiment of the present application, the U-shaped magnetic core portion 70 includes a first magnetic core portion 72 and a second magnetic core portion 74 parallel to each other, and a third magnetic core portion 76 whose two ends are respectively connected to the first magnetic core portion 72 and the second magnetic core portion 74, the first end of the first magnetic core portion 72 and the first end of the second magnetic core portion 74 are respectively connected to the coil bearing portion 20, the second end of the first magnetic core portion 72 and the second end of the second magnetic core portion 74 are respectively connected to the two ends of the third magnetic core portion 76; the first magnetic core portion 72 and the second magnetic core portion 74 are respectively perpendicular to the first plane where the axis A is located, and the projection of the third magnetic core portion 76 on the first plane forms a preset angle with the axis A.
[0036] The lower end surfaces of the first magnetic core part 72 and the second magnetic core part 74 of the U-shaped magnetic core part 70 can be snap-connected to the corresponding positions of the coil bearing part 20, for example, in the form of a drawer handle, a groove or a hole is opened in the area of the coil bearing part 20 corresponding to the connection between the first magnetic core part 72 and the second magnetic core part 74, and the partial magnetic cores at the ends of the first magnetic core part 72 and the second magnetic core part 74 are embedded and fixed to the corresponding grooved or holed areas of the coil bearing part 20.
[0037] When the first core part 72 and the second core part 74 are mounted on the coil bearing part 20 at their ends, the planes where their respective ends are located are perpendicular to the first plane where the axis A is located, and the third core part 76 is connected to the other ends of the first core part 72 and the second core part 74 away from the coil bearing part 20, respectively, that is, the third core part 76 is parallel to the first plane and spaced a predetermined distance apart, and the projection of the third core part 76 on the first plane has an angle with the axis A. In different embodiments, the value of the angle is preset to be different.
[0038] In the embodiment of the present application, the excitation coil 50 and the induction coil 60 wound on the coil bearing portion 20 are independently arranged from the elevator wire rope 40. When the excitation magnetic field generated by the excitation coil 50 causes the elevator wire rope 40 to reach saturation magnetization, the influence of magnetic field attenuation between the elevator wire rope 40 and the induction coil 60 can be avoided, thereby ensuring the accuracy of stress measurement and facilitating on-site installation and maintenance of the stress sensor without disassembling the elevator wire rope.
[0039] The stress sensor of the present application is described below in conjunction with different embodiments.
[0040] refer to Figure 1 , Figure 1 Schematic diagram of the structure of the elevator wire rope stress sensor of the first embodiment of the present application. Figure 1 As shown, there is one U-shaped magnetic core portion 70 , which is disposed on one side of the coil bearing portion 20 .
[0041] In this embodiment, the preset angle is 0. That is, the projection of the third core portion 76 on the first plane is parallel to or coincides with the axis A. Optionally, the excitation coil 50 is disposed on the first core portion 72 of the U-shaped core portion 70, and the induction coil 60 is disposed on the second core portion 74 of the U-shaped core portion 70. Alternatively, the excitation coil 50 is disposed on the second core portion 74 of the U-shaped core portion 70, and the induction coil 60 is disposed on the first core portion 72 of the U-shaped core portion 70.
[0042] In this way, after the AC excitation signal generated by the signal generator is input into the excitation coil 50, an excitation magnetic field is generated in the closed loop formed by the elevator wire rope 40 and the U-shaped magnetic core 70. And an induced voltage is generated in the induction coil 60. When the elevator wire rope 40 is subjected to an axial force, the magnetic permeability of the elevator wire rope 40 changes, causing the magnetic induction intensity of the entire closed loop to change, so that the output voltage at both ends of the induction coil 60 also changes. The voltage output by the induction coil 60 is collected by a data acquisition card and provided to the computer end, so that the axial stress of the elevator wire rope 40 can be measured.
[0043] Since the elevator wire rope 40 will vibrate when the elevator is running, Figure 1 When the stress sensor with a single-side U-shaped magnetic core 70 is used to test the axial force of the elevator wire rope 40, the air gap between the U-shaped magnetic core 70 and the elevator wire rope 40 will change due to the vibration of the elevator wire rope 40, resulting in Figure 1 The magnetic flux changes in the closed loop corresponding to the embodiment, thereby affecting the stress measurement accuracy. Based on this, the present application proposes Figure 2 A stress sensor of an embodiment.
[0044] refer to Figure 2 , Figure 2 Schematic diagram of the structure of the elevator wire rope stress sensor of the second embodiment of the present application. Figure 2 As shown, there are two U-shaped magnetic core parts 70, which are respectively arranged on the first side and the second side opposite to the coil bearing part 20. For example, the first side is the upper side of the coil bearing part 20, and the second side is the lower side of the coil bearing part 20.
[0045] In this embodiment, the preset angle is not 0. That is, the projection of the third magnetic core portion 76 on the first plane has an angle with the axis A. Figure 4 , Figure 4 FIG. 4 is a top view of a U-shaped magnetic core portion of a stress sensor according to a second embodiment of the present application.
[0046] from Figure 4 It can be seen that the axis of the third core portion 76 of the U-shaped core portion 70 located on the first side of the coil bearing portion 20 is B, and the projection of the axis B on the first plane forms a non-zero angle with the axis A. The axis of the third core portion 76 of the U-shaped core portion 70 located on the second side of the coil bearing portion 20 is C, and the projection of the axis C on the first plane forms a non-zero angle with the axis A.
[0047] In this embodiment, the excitation coil 50 is disposed on the third magnetic core portion 76 on the first side, and the induction coil 60 is disposed on the third magnetic core portion 76 on the second side.
[0048] Combination Figure 2 In the embodiment, the excitation coil 50 is arranged on the third core portion 76 of the U-shaped core portion 70 on the upper side of the coil bearing portion 20, and the induction coil 60 is arranged on the third core portion 76 of the U-shaped core portion 70 on the lower side of the coil bearing portion 20.
[0049] Alternatively, the excitation coil 50 is disposed on the third core portion 76 of the U-shaped core portion 70 on the upper side of the coil carrier 20 , and the induction coil 60 is disposed on the third core portion 76 of the U-shaped core portion 70 on the lower side of the coil carrier 20 .
[0050] By separating the excitation coil 50 from the induction coil 60, respectively winding them around the third core portion 76 of a U-shaped core portion 70, and arranging the two U-shaped core portions 70 on opposite sides of the elevator wire rope 40, compensation for the air gap change caused by the vibration of the elevator wire rope 40 can be achieved, thereby improving the accuracy and stability of the axial force measurement of the elevator wire rope 40.
[0051] In one embodiment, the two U-shaped magnetic core portions 70 arranged on opposite sides of the coil bearing portion 20 can be arranged in parallel, that is, the projection of the third magnetic core portion 76 of the U-shaped magnetic core portion 70 arranged on the upper side of the coil bearing portion 20 on the first plane can be parallel or overlapped with the projection of the third magnetic core portion 76 of the U-shaped magnetic core portion 70 arranged on the lower side of the coil bearing portion 20 on the first plane.
[0052] In another embodiment, in combination Figure 2 and Figure 3 It can be seen that there is a preset angle between the two U-shaped magnetic core portions 70 disposed on opposite sides of the coil bearing portion 20. That is, the projection of the third magnetic core portion 76 of the U-shaped magnetic core portion 70 disposed on the upper side of the coil bearing portion 20 on the first plane and the projection of the third magnetic core portion 76 of the U-shaped magnetic core portion 70 disposed on the lower side of the coil bearing portion 20 on the first plane have an angle that is not zero.
[0053] Optionally, a preset angle formed by the third magnetic core portion on the first side and the axis A is 45 degrees, and a preset angle formed by the third magnetic core portion on the second side and the axis A is 135 degrees.
[0054] That is, the two U-shaped magnetic core parts 70 are arranged orthogonally on the upper and lower sides of the elevator wire rope 40 and form a 45° angle with the elevator wire rope 40. Figure 5 As shown, the air gap change caused by the vibration of the elevator wire rope 40 can be further compensated, thereby improving the accuracy and stability of the axial force measurement of the elevator wire rope 40.
[0055] In the above embodiments, the U-shaped core 70 may include a silicon steel core or a soft ferrite core. The U-shaped core 70 made of high magnetic permeability material can enhance the magnetic field effect, resulting in a stronger induced voltage signal, which is convenient for signal collection and stress measurement.
[0056] In addition, the diameter of the enameled wire wound around the excitation coil 50 can be set to, for example, 0.3 mm, the excitation current can be set to 1 mA to 100 mA, and the number of turns of the excitation coil 50 can be set to, for example, 300 turns, so as to generate a sufficiently large excitation magnetic field when the excitation current is constant, and the excitation signal frequency is 3 kHz to 10 kHz to avoid the main interference frequency points.
[0057] Under the excitation of the AC signal, the induction coil 50 generates an induced voltage only in the brief moment when the excitation magnetic field suddenly changes, and there is no need to consider the power carrying problem. Therefore, the wire diameter of the induction coil 50 can be relatively small. At the same time, the number of turns of the induction coil 50 is related to the size of the output induced voltage. The more turns, the higher the output voltage. Therefore, in one embodiment, the wire diameter of the induction coil 50 is selected to be 0.15 mm and the number of turns is 600.
[0058] The stress sensor can be installed at the target fixed position through the base based on the installation position of the elevator wire rope, so that the excitation coil and the induction coil do not move with the elevator wire rope, will not interfere with the movement of the elevator wire rope, and will not damage the structure of the elevator wire rope, thereby avoiding affecting the safe operation of the elevator.
[0059] In an embodiment of the present application, the stress sensor includes a coil bearing portion, a U-shaped magnetic core portion, an excitation coil and an induction coil, and the U-shaped magnetic core portion is arranged on the coil bearing portion, the excitation coil is arranged on the U-shaped magnetic core portion to receive an excitation current to generate an excitation magnetic field, and the induction coil is arranged on the U-shaped magnetic core portion to output an induced voltage signal, whereby the excitation coil and the induction coil are independently wound from the elevator wire rope. When the excitation magnetic field generated by the excitation coil causes the elevator wire rope to reach saturation magnetization, the influence of magnetic field attenuation between the elevator wire rope and the induction coil can be avoided, thereby ensuring the accuracy of stress measurement, and facilitating on-site installation and maintenance of the stress sensor without disassembling the elevator wire rope.
[0060] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.
Claims
1. A stress sensor, characterized in that: include: A coil bearing portion, wherein the coil bearing portion forms a through hole, and the elevator wire rope is movably arranged in the through hole along the axis direction of the through hole; A U-shaped magnetic core portion, arranged on the coil bearing portion; An excitation coil, disposed on the U-shaped magnetic core portion, the excitation coil receiving an excitation current to generate an excitation magnetic field; The induction coil is arranged on the U-shaped magnetic core part, and the induction coil outputs an induced voltage signal.
2. The stress sensor according to claim 1, wherein: The U-shaped magnetic core portion includes a first magnetic core portion and a second magnetic core portion parallel to each other, and a third magnetic core portion having two ends respectively connected to the first magnetic core portion and the second magnetic core portion, a first end of the first magnetic core portion and a first end of the second magnetic core portion are respectively connected to the coil bearing portion, and a second end of the first magnetic core portion and a second end of the second magnetic core portion are respectively connected to two ends of the third magnetic core portion; The first magnetic core portion and the second magnetic core portion are respectively perpendicular to a first plane where the axis is located, and a projection of the third magnetic core portion on the first plane forms a preset angle with the axis.
3. The stress sensor according to claim 2, characterized in that: The number of the U-shaped magnetic core part is one, and the U-shaped magnetic core part is arranged on one side of the coil bearing part.
4. The stress sensor according to claim 3, characterized in that: The preset angle is 0.
5. The stress sensor according to claim 4, characterized in that: The excitation coil is disposed on the first core portion of the U-shaped core portion, and the induction coil is disposed on the second core portion of the U-shaped core portion.
6. The stress sensor according to claim 2, wherein: The number of the U-shaped magnetic core parts is two, which are respectively arranged on a first side and a second side opposite to the coil bearing part.
7. The stress sensor according to claim 6, characterized in that: The preset angle is not 0.
8. The stress sensor according to claim 7, characterized in that: The excitation coil is disposed on the third magnetic core portion on the first side, and the induction coil is disposed on the third magnetic core portion on the second side.
9. The stress sensor according to claim 8, characterized in that: The preset angle formed by the third magnetic core portion on the first side and the axis is 45 degrees, and the preset angle formed by the third magnetic core portion on the second side and the axis is 135 degrees.
10. The stress sensor according to any one of claims 1 to 9, characterized in that: The U-shaped magnetic core portion includes a silicon steel magnetic core or a soft ferrite magnetic core.