Adjustable Eddy Current Pen Probe

Abstract

The present invention provides an adjustable eddy current pen-type probe, which comprises a handle, a pull rod assembly, a rotating mechanism, a telescopic mechanism, a coil circuit assembly, a wiring base and a rod body housing. The rotating mechanism is installed inside the handle. One end of the pull rod assembly is installed inside the handle. The rotating mechanism is rotatably connected to one end of the pull rod assembly. The rod body housing is installed outside the pull rod assembly. The telescopic mechanism is connected to the rod body housing. The wiring base is installed at one end of the telescopic mechanism. The other end of the pull rod assembly is in contact with the wiring base. The coil circuit assembly is installed inside the telescopic mechanism. One side of the wiring base is connected to the coil wire in the coil circuit assembly, and the other side is connected to at least two wires to a wire interface to form a coil circuit. The present invention is an eddy current pen-type probe that can adjust the bending angle and change the end length, thereby overcoming the deficiencies of the prior art and fully meeting the detection requirements of the edges of fastener holes in various connection structures on the aircraft in-situ state.

Description

Technical Field

[0001] The invention relates to the field of nondestructive testing equipment, in particular to an adjustable eddy current pencil probe. Background Art

[0002] In the prior art, high-frequency eddy current detection technology is usually used to detect fatigue cracks that occur at the edge of fastener holes on aircraft, and an eddy current pencil probe is required for detection. During the detection, the end of the probe is placed at the edge of the fastener hole, and the coil inside the probe excites an eddy current field on the surface of the object being tested, and senses the impedance change signal of the received eddy current field to determine whether there is a crack.

[0003] The perpendicularity between the eddy current coil and the surface being tested is a key issue in the reliability of this type of eddy current testing. At present, in order to place the eddy current pencil probe coil perpendicular to the surface of the object being tested, it is usually necessary to select or customize a probe with a suitable bending angle and end length according to the structural characteristics.

[0004] Since there are a large number of different types of fastener connection structures on aircraft that require eddy current testing, and there are a large number of in-situ structures or system pipe parts that are blocked, inspectors need to frequently replace probes during testing to ensure that the probe coil is perpendicular to the surface being tested. When conventional probe angles cannot meet the testing requirements, probes with specific bending angles need to be customized, and after replacing the probe during the testing process, the instrument debugging and calibration steps need to be repeated, which is time-consuming. In addition, the large number of probe types used will also increase the cost of purchasing and managing probes for airlines, which invisibly increases the cost of aircraft operation and maintenance.

[0005] The Chinese invention patent with application number CN210711220940.1 discloses an in-situ eddy current detection transmission device for engine blades. The device includes an eddy current probe, a spring, a movable joint, a rear section tube, an optical fiber fixing clamp and a transmission joint adjustment nut. The rotation angle of the front section tube is controlled by adjusting the nut and the threaded screw. However, the length of the front section tube is fixed and does not have an adjustment function, which has limitations in the application of in-situ fastener hole detection in aircraft.

[0006] The Chinese invention patent with application number CN201910685467.7 discloses a probe for a thermal power steel ball eddy current flaw detector. The probe includes a probe body, a mounting shell, a first through hole, a second through hole and a cover. The probe adjusts its angle through the movement of a telescopic cylinder fixed on the inner wall of the probe tube, but it is not suitable for the detection of in-situ fastener holes in aircraft.

[0007] The Chinese invention patent with the application number CN202022973837.8 discloses an adjustable probe device for pulsed eddy current detection of pipes with cladding layers. The invention sets an arc-shaped inclined end and a straight end structure at the bottom of the adjusting device to achieve close fitting between the bottom of the probe and the pipe or the cladding layer outside the pipe, meeting the measurement of different pipe diameters. However, it cannot detect the narrow space at the hole edge of aircraft structure fasteners, and has great limitations in the in-situ detection application of aircraft.

[0008] In view of this, the inventor of this application has designed an adjustable eddy current pen-type probe in order to overcome the above technical problems. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide an adjustable eddy current pen-type probe in order to overcome the limitations in the use of eddy current pen-type probes in the prior art, the need to frequently replace the probe, and the relatively high maintenance cost.

[0010] The present invention solves the above technical problems through the following technical solutions:

[0011] An adjustable eddy current pen-type probe, characterized in that the adjustable eddy current pen-type probe includes a handle, a pull rod assembly, a rotating mechanism, a telescopic mechanism, a coil circuit assembly, a wiring base, and a rod body housing. The rotating mechanism is installed in the handle, one end of the pull rod assembly is installed in the handle, the rotating mechanism is rotatably connected to one end of the pull rod assembly, and the rod body housing is installed outside the pull rod assembly;

[0012] The telescopic mechanism is connected to the rod body housing, the wiring base is installed at one end of the telescopic mechanism, the other end of the pull rod assembly is in contact with the wiring base, the coil circuit assembly is installed in the telescopic mechanism, one side of the wiring base is connected to the coil wire in the coil circuit assembly, and the other side is connected to at least two wires to the wire interface at the tail of the adjustable eddy current pen-type probe to form a coil circuit.

[0013] According to an embodiment of the present invention, the rotating mechanism includes a knob, a screw rod, and a gear. The screw rod is fixed in the handle, the knob is installed at the end of the screw rod, located outside the handle, and the gear meshes with the screw rod.

[0014] According to an embodiment of the present invention, the pull rod assembly includes at least one set of symmetrically distributed pull rods. A tooth portion is provided at one end of the pull rod, and the gear meshes with the tooth portion of the pull rod.

[0015] According to an embodiment of the present invention, the telescopic mechanism includes a telescopic sleeve rod. The wiring base is sleeved at one end of the telescopic sleeve rod, and the rod body housing is rotatably connected to the wiring base.

[0016] According to an embodiment of the present invention, a foldable conductive hose is sleeved at the connection between the rod body housing and the telescopic sleeve rod.

[0017] According to an embodiment of the present invention, a first installation groove is provided on the outer wall surface of the rod body housing, a second installation groove is provided on the outer wall surface of the telescopic sleeve rod, one end of the conductive hose is installed in the first installation groove, and the other end is installed in the second installation groove.

[0018] According to an embodiment of the present invention, the coil circuit assembly includes a coil and a winding wheel. The coil is installed at the inner top end of the telescopic sleeve rod for collecting eddy current detection signals. The winding wheel is fixed on the wiring base. The wires of the coil are wound around both ends of the winding wheel in opposite directions, and the wires of the coil are respectively connected to one side of the wiring base.

[0019] According to an embodiment of the present invention, an elastic non-conductive energy storage device is provided inside the winding wheel.

[0020] According to an embodiment of the present invention, the rod body housing is a metal hollow cylindrical shell with a triangular end. A rotating shaft is fixed at one end of the rod body housing, and it is rotatably connected to the wiring base through the rotating shaft.

[0021] According to an embodiment of the present invention, at least one elastic limiter is installed on the telescopic sleeve rod. A plurality of openings are provided on the telescopic sleeve rod. The length of the telescopic sleeve rod is adjusted by the elastic limiter popping out at the corresponding openings.

[0022] The positive and progressive effects of the present invention are as follows:

[0023] The adjustable eddy current pen-type probe of the present invention can not only adjust the bending angle but also change the end length, thus overcoming the deficiencies of the prior art and fully meeting the detection requirements of the hole edges of fasteners in various connection structures in-situ on the aircraft. Brief Description of the Drawings

[0024] The above-mentioned and other features, properties, and advantages of the present invention will become more obvious through the following description in conjunction with the drawings and embodiments. The same reference numerals in the drawings always represent the same features, where:

[0025] Figure 1 It is the front view of the adjustable eddy current pen-type probe of the present invention.

[0026] Figure 2 It is the top view of the adjustable eddy current pen-type probe of the present invention.

[0027] Figure 3Schematic diagram of the rotating mechanism in the adjustable eddy current pen-type probe of the present invention in a stationary state.

[0028] Figure 4 Schematic diagram of the rotating mechanism in the adjustable eddy current pen-type probe of the present invention in a working state.

[0029] Figure 5 Top view of the rotating mechanism in the adjustable eddy current pen-type probe of the present invention.

[0030] Figure 6 It is Figure 5 Enlarged view of part A in

[0031] Figure 7 Schematic diagram of the state of the telescopic mechanism in the adjustable eddy current pen-type probe of the present invention Figure 1 .

[0032] Figure 8 Schematic diagram of the state of the telescopic mechanism in the adjustable eddy current pen-type probe of the present invention Figure 2 .

[0033] Figure 9 Front view of the coil circuit component in the adjustable eddy current pen-type probe of the present invention.

[0034] Figure 10 Top view of the coil circuit component in the adjustable eddy current pen-type probe of the present invention.

[0035] Figure 11 Right view of the coil circuit component in the adjustable eddy current pen-type probe of the present invention.

[0036] Figure 12 Schematic diagram of the state of the coil circuit component in the adjustable eddy current pen-type probe of the present invention Figure 1 .

[0037] Figure 13 Schematic diagram of the state of the coil circuit component in the adjustable eddy current pen-type probe of the present invention Figure 2 .

[0038] Figure 14 Structural schematic diagram of the conductive hose in the adjustable eddy current pen-type probe of the present invention.

[0039] Figure 15 Installation schematic diagram of the conductive hose in the adjustable eddy current pen-type probe of the present invention.

[0040] Figure 16 It is Figure 15 Enlarged view of part B in

[0041] Figure 17 Schematic diagram of the state of the rod body housing, conductive hose and telescopic mechanism in the adjustable eddy current pen-type probe of the present invention Figure 1 .

[0042] Figure 18 Schematic diagram of the states of the rod body housing, conductive hose, and telescopic mechanism in the adjustable eddy current pen-type probe of the present invention Figure 2 。

[0043] Figure 19 Schematic diagram of the states of the rod body housing, conductive hose, and telescopic mechanism in the adjustable eddy current pen-type probe of the present invention Figure 3 。

[0044] Figure 20 Schematic diagram of the state of the adjustable eddy current pen-type probe of the present invention in the in-situ state a

[0045] Figure 21 Schematic diagram of the state of the adjustable eddy current pen-type probe of the present invention in the in-situ state b

[0046] Figure 22 Schematic diagram of the state of the adjustable eddy current pen-type probe of the present invention in the in-situ state c

[0047] Handle 10 Tie rod assembly 20 Rotating mechanism 30 Telescopic mechanism 40 Wiring base 50 Rod body housing 60 Wire 70 Wire interface 80 Knob 31 Screw rod 32 Gear 33 Tie rod 21 Tooth part 211 Telescopic sleeve rod 41 Second installation groove 42 Limiter 43 Coil 100 Winding wheel 110 Rotating shaft 61 Conductive hose 130 First installation groove 62 Adjustable eddy current pen-type probe 200 Detailed implementation manners

[0048] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following provides a detailed description of the specific implementation manners of the present invention in conjunction with the accompanying drawings

[0049] Now, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Now, preferred embodiments of the present invention will be described in detail, and examples thereof are shown in the drawings. Whenever possible, the same reference numerals will be used throughout the drawings to represent the same or similar parts

[0050] In addition, although the terms used in the present invention are selected from well-known and commonly used terms, some of the terms mentioned in the specification of the present invention may be selected by the applicant according to his or her judgment, and their detailed meanings are described in the relevant parts of the description herein

[0051] In addition, it is required to understand the present invention not only through the actual terms used, but also through the meaning implied by each term

[0052] Such as Figure 1 and Figure 2As shown in the figure, the present invention discloses an adjustable eddy current pen-type probe 200, which includes a handle 10, a pull rod assembly 20, a rotating mechanism 30, a telescopic mechanism 40, a coil circuit assembly, a wiring base 50 and a rod body housing 60. The rotating mechanism 30 is installed in the handle 10, one end of the pull rod assembly 20 is installed in the handle 10, the rotating mechanism 30 is rotatably connected to one end of the pull rod assembly 20, and the rod body housing 60 is installed outside the pull rod assembly 20. The telescopic mechanism 40 is connected to the rod body housing 60, the wiring base 50 is installed at one end of the telescopic mechanism 40, and the other end of the pull rod assembly 20 is in contact with the wiring base 50. The coil circuit assembly is installed in the telescopic mechanism 40. One side of the wiring base 50 is connected to the coil wire in the coil circuit assembly, and the other side is connected to at least two wires 70 to the wire interface 80 at the tail of the adjustable eddy current pen-type probe to form a coil circuit.

[0053] As Figures 3 to 6 shown in the figure, the rotating mechanism 30 includes a knob 31, a screw 32 and a gear 33. The screw 32 is fixed in the handle 10, the knob 31 is installed at the end of the screw 32, located outside the handle 10, and the gear 33 meshes with the screw 32. The pull rod assembly 20 includes at least one set of symmetrically distributed pull rods 21. A tooth portion 211 is provided at one end of the pull rod 21, and the gear 33 meshes with the tooth portion 211 of the pull rod 21.

[0054] Here, the gear 33 is preferably a two-stage gear. One stage meshes with the middle of the screw 32, and the other stage meshes with two symmetrically distributed toothed pull rods 21. The distal end of the pull rod 21 is semi-circular and contacts the wiring base 50 at the end. By turning the knob 31, the screw 32 rotates, and the relative positions of the two pull rods 21 are changed through the transmission of the moving gear, so as to control the rotation of the end to achieve the function of adjusting the bending angle of the probe.

[0055] The knob 31 and the screw 32 are connected and fixed to the handle 10. The screw 32 controls two symmetrically distributed pull rods 21 that are reversely meshed with the gear 33 through two-stage gear transmission. The right end of the pull rod 21 is semi-circular and abuts against the wiring base 50. There is a cylindrical through hole in the middle of the wiring base 50, and the rotating shaft of the hollow cylindrical shell passes through the through hole to form a fulcrum. Therefore, the rotating mechanism changes the relative positions of the two pull rods 21 by turning the knob 31, so that the wiring base 50 rotates with the rotating shaft as the fulcrum, thereby realizing the rotation of the probe end.

[0056] As Figure 7 and Figure 8As shown, the telescopic mechanism 40 includes a telescopic sleeve rod 41. The wiring base 50 is sleeved on one end of the telescopic sleeve rod 41, and the rod body housing 60 is rotatably connected to the wiring base 50. Preferably, at least one elastic limiter 43 is installed on the telescopic sleeve rod 41, and a plurality of openings are provided on the telescopic sleeve rod 41. The elastic limiter 43 pops out at the corresponding openings to realize the length adjustment of the telescopic sleeve rod 41.

[0057] The telescopic mechanism 40 includes a metal telescopic sleeve rod 41 connected to the wiring base 50. There are several openings on the outer shell of the telescopic sleeve rod 41, which allow the elastic limiter 43 to pop out at the openings. By placing the elastic limiter 43 at different openings, the length of the sleeve rod can be adjusted.

[0058] For changing the length of the probe tip, the limiter 43 is installed on the inner rod of the metal telescopic sleeve rod 41. The limiter 43 is equipped with an elastic energy storage device such as a spring. There are limit openings on the outer rod of the metal telescopic sleeve rod 41. During operation, press the elastic limiter 43 on the sleeve rod and pull the inner rod of the sleeve rod to make the limiter 43 pop out at the openings at the appropriate positions on the outer rod of the sleeve rod, so as to change the length of the probe tip to meet the in-situ detection length requirements.

[0059] As Figure 9 and Figure 13 As shown, the coil circuit assembly includes a coil 100 and a winding wheel 110. The coil 100 is installed at the inner top end of the telescopic sleeve rod 41 for collecting eddy current detection signals. The winding wheel 110 is fixed on the wiring base 50. The wires 70 of the coil 100 are wound around both ends of the winding wheel 110 in opposite directions, and the wires 70 of the coil 100 are respectively connected to one side of the wiring base 50.

[0060] Further preferably, an elastic non-conductive energy storage device is provided inside the winding wheel 110, so that when the length of the sleeve rod changes, the coil 100 can always be fixed at the head of the sleeve rod to stably collect signals. The two blades of the wiring base 50 are insulated from each other and non-conductive. The wiring base 50 is sleeved on the end of the telescopic sleeve rod 41. One side is connected to the coil wire in the telescopic sleeve rod, and the other side is connected to the other two wires 70 to the wire interface 80 at the tail of the probe, thus forming a coil circuit. When the knob 31 is turned to change the angle of the probe, the wires in the coil circuit will not be bent and damaged.

[0061] The coil loop assembly is mainly used to connect the coil that collects signals at the probe head and the wire connector at the tail, forming a closed loop to conduct electrical signals. The coil loop involves components such as wire interface 80, wire 70, wiring base 50, wire winding wheel 110, coil 100, etc. One end of wire 70 is connected to wire interface 80, and the other end is connected to wiring base 50. The wiring base 50 is divided into left and right sides, both of which can conduct electricity, but are separated by an insulating layer from each other. The left and right sides are insulated from each other and from the outer shell of the telescopic rod 41. A wire winding wheel annular bracket is fixed on the wiring base 50, and the wire winding wheel 110 is installed in the annular bracket and can rotate. Inside the cavity of the wire winding wheel 110, there are elastic energy storage devices such as a spring made of non-metallic materials, which are connected to the wiring base 50. The wires are symmetrically wound around both ends of the wire winding wheel 110 in clockwise and counterclockwise directions respectively, and extend towards the probe head to be connected to the coil 100, forming a closed loop.

[0062] During operation, when it is necessary to extend or shorten the telescopic rod, the wire 70 in the internal coil loop pulls the elastic wire winding wheel 110 to rotate. The elastic energy storage device inside the wire winding wheel 110 tightens or relaxes, so that the electromagnetic fields formed by the wires 70 at both ends of the wire winding wheel 110 always maintain the same magnitude and opposite directions. Then, the electromagnetic field signals caused by the change in wire length can cancel each other out, thus avoiding the generation of interference signals that interfere with the detection of defects by the coil at the probe head. When the probe changes its bending angle, it is achieved by rotating the wiring base. The wires on both sides of the wiring base 50 do not bend, thus avoiding damage to the wires due to the change in the bending angle of the probe.

[0063] Further preferably, the rod body outer shell 60 is a metal hollow cylindrical shell with one end being triangular. A rotating shaft 61 is fixed at one end of the rod body outer shell 60, and it is rotationally connected to the wiring base 50 through the rotating shaft 61.

[0064] As Figures 14 to 19 shown, a foldable conductive hose 130 is sleeved at the connection between the rod body outer shell 60 and the telescopic rod 41. For its installation method, for example, a first installation groove 62 is provided on the outer wall surface of the rod body outer shell 60, and a second installation groove 42 is provided on the outer wall surface of the telescopic rod 41. One end of the conductive hose 130 is installed in the first installation groove 62, and the other end is installed in the second installation groove 42.

[0065] In the adjustable eddy current pen-type probe, the rod body outer shell 60 includes a metal hollow cylindrical shell with one end shaped like a triangle. A rotating shaft 61 is fixed at the end for connecting to the wiring base 50. A foldable conductive hose 130 is sleeved at the bending part of the probe, so that the cylindrical shell and the metal telescopic rod 40 are combined into a complete probe outer shell, achieving the functions of protecting the internal structure of the probe and forming a shielding cavity to shield external magnetic fields.

[0066] More specifically, the rod body housing 60 is mainly used to protect the internal structure of the probe and shield external interfering magnetic fields. The rod body housing 60 is preferably a metal hollow cylindrical shell, which is combined with a foldable metal film hose (i.e., the conductive hose 130) and a metal telescopic rod (i.e., the telescopic rod 40). One end of the metal hollow cylindrical shell is cut into a triangular shape, and a rotating shaft 61 is installed at the tip for supporting the probe end and providing sufficient space for the rotation of the end. An annular groove (i.e., the first mounting groove 62) is engraved on the shell wall near the triangular end for embedding the hose, and a similar groove (i.e., the second mounting groove 42) is engraved on the outer wall of the outer rod of the telescopic rod for embedding the other end of the hose. The hose is coated with a metal film and can be folded, so that the cylindrical shell, the hose and the telescopic rod are combined into a complete probe housing, realizing the functions of protecting the internal structure of the probe and forming a shielding cavity to shield external magnetic fields, so that the coil circuit will not be interfered by the external magnetic field of the probe to generate noise signals.

[0067] As Figures 20 to 22 shown, when performing in-situ detection of the edges of fastener holes in aircraft structures, according to the in-situ detection situation where the object to be detected is blocked by structural components or system pipeline components, adjust the position of the knob 31 on the probe handle and the limiter on the probe telescopic rod, change the bending angle of the probe and the length of the end, so that the probe coil can be perpendicular to the detected surface for detection, improve the accuracy of eddy current detection, reduce the types and numbers of probes used, and reduce the operation and maintenance costs of the aircraft.

[0068] Compared with the prior art, the adjustable eddy current pen-type probe of the present invention has the functions of adjustable bending angle and end length. When detecting the edges of fastener holes in different in-situ states, it is not necessary to frequently replace probes with different bending angles and end lengths or customize special probes in order to make the internal coil of the probe perpendicular to the detection surface. It can meet the in-situ detection requirements of various connection structures on the aircraft, and can reduce the detection time and cost compared with using traditional detection probes, improving the detection efficiency and accuracy.

[0069] In summary, the adjustable eddy current pen-type probe of the present invention is an eddy current pen-type probe that can not only adjust the bending angle but also change the end length, thus overcoming the deficiencies of the prior art and fully meeting the detection requirements of the edges of fastener holes in various connection structures in-situ on the aircraft.

[0070] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these are only examples. The protection scope of the present invention is defined by the appended claims. Without departing from the principles and essence of the present invention, those skilled in the art can make various changes or modifications to these embodiments, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. An adjustable eddy current pen-type probe, characterized in that, the adjustable eddy current pen-type probe includes a handle, a pull rod assembly, a rotating mechanism, a telescopic mechanism, a coil circuit assembly, a wiring base, and a rod body housing. The rotating mechanism is installed inside the handle. One end of the pull rod assembly is installed inside the handle. The rotating mechanism is rotatably connected to one end of the pull rod assembly. The rod body housing is installed outside the pull rod assembly; the telescopic mechanism is connected to the rod body housing. The wiring base is installed at one end of the telescopic mechanism. The other end of the pull rod assembly contacts the wiring base. The coil circuit assembly is installed inside the telescopic mechanism. One side of the wiring base is connected to the coil wire in the coil circuit assembly, and the other side is connected to at least two wires to the wire interface at the tail of the adjustable eddy current pen-type probe to form a coil circuit; the telescopic mechanism includes a telescopic sleeve rod. The wiring base is sleeved at one end of the telescopic sleeve rod. The rod body housing is rotatably connected to the wiring base; the coil circuit assembly includes a coil and a winding wheel. The coil is installed at the inner top end of the telescopic sleeve rod for collecting eddy current detection signals. The winding wheel is fixed on the wiring base. The wires connected to the coil are wound around both ends of the winding wheel in opposite directions, and the wires connected to the coil are respectively connected to one side of the wiring base; an elastic non-conductive energy storage device is arranged inside the winding wheel.

2. The adjustable eddy current pen-type probe according to claim 1, characterized in that, the rotating mechanism includes a knob, a screw rod, and a gear. The screw rod is fixed inside the handle. The knob is installed at the end of the screw rod and is located outside the handle. The gear meshes with the screw rod.

3. The adjustable eddy current pen-type probe according to claim 2, characterized in that, the pull rod assembly includes at least one group of symmetrically distributed pull rods. One end of the pull rod is provided with a tooth portion. The gear meshes with the tooth portion of the pull rod.

4. The adjustable eddy current pen-type probe according to claim 1, characterized in that, a foldable conductive hose is sleeved at the connection between the rod body housing and the telescopic sleeve rod.

5. The adjustable eddy current pen-type probe according to claim 4, characterized in that, a first installation groove is arranged on the outer wall surface of the rod body housing, and a second installation groove is arranged on the outer wall surface of the telescopic sleeve rod. One end of the conductive hose is installed in the first installation groove, and the other end is installed in the second installation groove.

6. The adjustable eddy current pen-type probe according to claim 1, characterized in that, the rod body housing is a metal hollow cylindrical shell with one end being triangular. A rotating shaft is fixed at one end of the rod body housing and is rotatably connected to the wiring base through the rotating shaft.

7. The adjustable eddy current pen-type probe according to claim 1, characterized in that, at least one elastic limiter is installed on the telescopic sleeve rod. A plurality of openings are arranged on the telescopic sleeve rod. The length of the telescopic sleeve rod is adjusted by the elastic limiter popping out at the corresponding openings.

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