CN109884181A

CN109884181A - A kind of excitation coil for plane cylinder sensor

Info

Publication number: CN109884181A
Application number: CN201910173119.1A
Authority: CN
Inventors: 陈国龙; 宋致博; 王慷; 申涛
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2019-03-07
Filing date: 2019-03-07
Publication date: 2019-06-14
Anticipated expiration: 2039-03-07
Also published as: CN109884181B

Abstract

The present invention provides a kind of excitation coil for plane cylinder sensor, the shape of excitation coil is cyclic annular fractal curve, wherein, using the present invention obtain cyclic annular fractal curve design plane eddy current sensor excitation coil when, since the excitation coil of cyclic annular fractal curve has the characteristics that self similarity, the vortex for generating it in metal surface is distributed in more direction in regional area, the probability and intensity of vortex and crack interaction are increased, to effectively improve flat surface sensor to crackle Detection capability.

Description

A kind of excitation coil for plane cylinder sensor

Technical field

The invention belongs to technical field of nondestructive testing more particularly to a kind of excitation coils for plane cylinder sensor.

Background technique

Flexible flat eddy current sensor and its detection system are a kind of promising plane cylinder sensors of tool, and advantage exists In changeability, on the one hand can be changed when detecting according to the variation of piece surface shape, it on the other hand can be by sensor Shape be designed to the similar shape in tested part surface, to reduce Lift-off effect to the greatest extent.Currently, design plane is vortexed Simple geometries figure such as straight line, circle, rectangle, parallelogram and combinations thereof is mainly used when sensor, the above figure constitution Excitation coil is single due to inducing vortex direction in measured piece, so that particular orientation crackle a possibility that there are missing inspections is very Greatly.Therefore, it is necessary to a kind of excitation coils, can induce Eddy Distribution in more direction in metal surface regional area, with Improve the Detection capability of eddy current sensor different directions crackle.

Summary of the invention

To solve the above problems, the present invention provides a kind of excitation coil for plane cylinder sensor, can effectively mention High flat surface sensor is to crackle Detection capability.

A kind of excitation coil for plane cylinder sensor, the shape of the excitation coil are cyclic annular fractal curve, In, it is described ring-type fractal curve generation method the following steps are included:

S1: at least two rank iterative operations are executed in initial circle, obtain fractal graph, wherein iterative operation specifically:

M next stage circle of setting in upper level circle, wherein m next stage is round tangent and adjacent with upper level circle With also tangent between level-one circle, m=4k-2, k are positive integer, and the upper level circle of first order circle is initial circle, meanwhile, when executing two When more than rank iterative operation, in the round point of contact with upper level circle of next stage, at least 2 point of contacts coincide with upper level circle with The point of contact of upper level circle, the radius scale of the circle of adjacent two-stage are identical again；

S2: using the envelope line of most final stage circle in the fractal graph as the ring-type point for being used for plane cylinder sensor Shape curve.

The utility model has the advantages that

The present invention provides a kind of excitation coil for plane cylinder sensor, and the shape of excitation coil is that ring-type divides shape bent Line, wherein when the excitation coil for the cyclic annular fractal curve design plane eddy current sensor for using the present invention to obtain, due to ring-type point The excitation coil of shape curve has the characteristics that self similarity, and the vortex for generating it in metal surface is distributed in more in many ways in regional area Upwards, the probability and intensity of vortex and crack interaction are increased, energy is detected to crackle to effectively improve flat surface sensor Power.

Detailed description of the invention

Fig. 1 is initial round schematic diagram provided by the invention；

Fig. 2 is the schematic diagram of two first order of setting circle provided by the invention in initial circle；

Fig. 3 is the schematic diagram provided by the invention that two third level circle is arranged again in the circle of the second level；

Fig. 4 is the point of contact schematic diagram for needing to be overlapped in adjacent three-level circle provided by the invention；

Fig. 5 is the partial enlargement diagram of Fig. 4 provided by the invention；

Fig. 6 is the corresponding fractal graph schematic diagram of seven rank iterative operations under the conditions of m=2 provided by the invention；

Fig. 7 is the schematic diagram of six first order of setting circle provided by the invention in initial circle；

Fig. 8 is the corresponding fractal graph schematic diagram of quadravalence iterative operation under the conditions of m=6 provided by the invention；

Fig. 9 is the corresponding cyclic annular fractal curve schematic diagram of the quadravalence iterative operation under the conditions of m=6 provided by the invention.

Specific embodiment

In order to make those skilled in the art more fully understand application scheme, below in conjunction in the embodiment of the present application Attached drawing, the technical scheme in the embodiment of the application is clearly and completely described.

Embodiment one

Below with k=1, for m=2, to a kind of excitation coil for plane cylinder sensor provided by the invention into Row is described in detail, specifically includes the following steps:

Referring to Fig. 1, which is initial round schematic diagram provided in this embodiment；Seven rank iterative operations are executed in initial circle, Fractal graph is obtained, wherein the first rank iterative operation specifically:

Two first order circles of setting in initial circle, wherein two first order circles with initially justify tangent, and two are adjacent The first order circle between it is also tangent, as shown in Figure 2；

Second-order iterative operation specifically:

Two third level circle is set again in the circle of the second level, as shown in Figure 3, wherein two third level circles are and the first order Circle is tangent, and in the round point of contact with first order circle in the second level, at least coincides with first order circle there are two point of contact and cuts with initially round Point specifically may refer to the arrow instruction of Fig. 4, wherein Fig. 5 is the partial enlargement diagram of grey parts in Fig. 4；In addition, the The round radius scale with first order circle of second level, and first order circle are identical as the radius scale initially justified；

And so on, the setting third level circle in the circle of the second level, the setting fourth stage circle in third level circle, until completing seven Rank iterative operation obtains the corresponding fractal graph of seven rank iterative operations under the conditions of m=2, as shown in Figure 6；

Using the envelope line of afterbody circle in the fractal graph as the ring-type point for being used for plane cylinder sensor Shape curve.

Embodiment two

Below with k=2, for m=6, to a kind of excitation coil for plane cylinder sensor provided by the invention into Row is described in detail, specifically includes the following steps:

Quadravalence iterative operation is executed in initial circle, fractal graph is obtained, wherein the first rank iterative operation specifically:

Six first order circles of setting in initial circle, wherein six first order circles with initially justify it is tangent and adjacent two-by-two The first order circle between it is also tangent, as shown in Figure 7；

Second-order iterative operation specifically:

Six third level circles are set again in the circle of the second level, wherein six third level circles are tangent with first order circle, and the Second level circle is with the point of contact of first order circle, and at least there are two point of contacts to coincide with first order circle and initially round point of contact；In addition, second The round radius scale with first order circle of grade, and first order circle are identical as the radius scale initially justified；

And so on, the setting third level circle in the circle of the second level, the setting fourth stage circle in third level circle completes quadravalence and changes Generation operation, obtains the corresponding fractal graph of quadravalence iterative operation under the conditions of m=6, as shown in Figure 8；

Using the envelope line of afterbody circle in the fractal graph as the ring-type point for being used for plane cylinder sensor Shape curve, as shown in Figure 9.

Certainly, the invention may also have other embodiments, without deviating from the spirit and substance of the present invention, ripe Various corresponding changes and modifications can be made according to the present invention certainly by knowing those skilled in the art, but these it is corresponding change and Deformation all should fall within the scope of protection of the appended claims of the present invention.

Claims

1. a kind of excitation coil for plane cylinder sensor, which is characterized in that the shape of the excitation coil is cyclic annular point Shape curve, wherein it is described ring-type fractal curve generation method the following steps are included:

M next stage of setting circle in upper level circle, wherein m next stage circle and upper level are round tangent and adjacent same Also tangent, m=4k-2 between grade circle, k is positive integer, and the upper level circle of first order circle is initial circle, meanwhile, when execute two ranks with On iterative operation when, in the round point of contact with upper level circle of next stage, at least 2 point of contacts coincide with upper level circle with again on The point of contact of level-one circle, the radius scale of the circle of adjacent two-stage are identical；

S2: the envelope line of most final stage circle in the fractal graph is bent as the ring-type point shape for being used for plane cylinder sensor Line.