Full-coverage areal density measurement mechanism

Abstract

A full-coverage areal density measurement mechanism, comprising a plurality of groups of measurement units (1) distributed along the strip travel direction of a material under test. Each group of measurement units (1) is arranged on the same straight line along the web width direction of the material under test, two adjacent measurement units (1) in the web width direction of the material under test are respectively located on different straight lines, and the effective measurement widths of a plurality of measurement units (1) cover the web width of the material under test. Adjacent measurement units (1) are assembled together, so that full-coverage areal density measurement of any wide web material can be realized, and two adjacent measurement units (1) are not arranged on the same straight line, so that the influence of ray crossing on the accuracy of areal density profile measurement can be avoided; and in addition, a single measurement unit (1) has a relatively small ray fan beam angle, avoiding large-angle oblique incidence, and the difference in radiation quantity at different positions on an elongated light spot is small, ensuring relatively consistent results of areal density measurement across the entire web width.

Description

A surface density full inspection testing agency Technical Field

[0001] This invention relates to the field of areal density testing technology, specifically to an areal density full inspection testing mechanism. Background Technology

[0002] In the areal density testing of lithium battery electrodes, films, foils, etc., the process has evolved from sampling inspection to full inspection. The core idea of ​​achieving full inspection is line scanning, which generates a long strip of light that covers the entire width of the material being tested. The light is received and detected by a linear array detector. The relationship between the measured signal value and the areal density is established through calibration. Continuous detection is performed in the belt direction, thereby achieving full line scanning inspection of wide-width materials.

[0003] In X-ray areal density detection, there are three methods for generating elongated light spots: X-ray line sources, X-ray diverging sources, and X-ray distribution sources. Their disadvantages are as follows:

[0004] (1) An X-ray source, combined with grid collimation in front of a linear array detector, is an ideal way to achieve full inspection, but it is still some distance from commercial X-ray sources.

[0005] (2) X-ray diverging source, which uses a single high-power X-ray source to generate a long strip of light spot on a wide material through collimation constraint. However, the disadvantage is that when the width is large, the angle of incidence of the X-ray at the edge position is large, which is not conducive to the detection of the surface density profile at the edge. In addition, the difference in X-ray radiation between the middle and the edge positions is large, resulting in a large difference in the repeatability accuracy of surface density detection at the edge position compared with that at the middle position.

[0006] (3) The X-ray distribution source has its focal point distributed on a line. When the X-ray fan beams are simultaneously lit and spliced ​​on the detection material, since there is still a certain distance between the detection material and the linear array detector, after splicing on the detection material, the X-rays will cross on the linear array detector. Such crossover will affect the accuracy of surface density profile detection. Summary of the Invention

[0007] The purpose of this invention is to provide a surface density full inspection testing mechanism to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a surface density full inspection testing mechanism, comprising a plurality of groups of testing units distributed along the belt direction of the testing material, wherein each group of testing units is arranged on the same straight line along the width direction of the testing material, and two adjacent testing units in the width direction of the testing material are located on different straight lines, and the effective detection width of the plurality of testing units covers the width of the testing material.

[0009] Furthermore, the effective detection widths of several detection units are connected end-to-end in the width direction of the detection material, and the sum of the effective detection widths of the detection units is greater than the width of the detection material.

[0010] Furthermore, the detection units have the same structure, and each detection unit includes a radiation source, a collimator installed at the bottom of the radiation source, and a linear array detector positioned directly below the collimator. The collimator is used to constrain the radiation emitted by the radiation source into a fan-shaped beam. The fan-shaped beam illuminates the linear array detector to produce a long strip of light, and the long strip of light covers the length of the linear array detector. The linear array detector is used to receive the radiation from the radiation source.

[0011] Furthermore, several X-ray sources and collimators are fixed in the same outer shell, and several linear array detectors are fixed in the same outer shell. A gap is reserved between the two outer shells to accommodate the material to be tested passing through. The height planes of the X-ray sources and linear array detectors are parallel to the plane of the material to be tested.

[0012] Furthermore, the radiation sources and linear array detectors are in one-to-one correspondence, and the fan-shaped beam of any one radiation source will not irradiate the other linear array detectors.

[0013] Compared with existing technologies, the areal density full inspection detection mechanism proposed in this invention, while generating elongated light spots for line scanning full inspection, has the following beneficial effects:

[0014] (1) The focal points of the X-ray source are distributed adjacently and alternately on two straight lines to avoid the X-rays crossing and affecting the accuracy of surface density profile detection;

[0015] (2) The effective detection width of a single detection unit on the detection material, and the splicing of adjacent detection units, can be more flexible in dealing with the width of the detection material, and can realize full detection of the surface density of materials of any width.

[0016] (3) The angle of the X-ray fan beam of a single detection unit is small, which avoids large-angle oblique incidence, and the difference in radiation at different positions on the long strip spot is small, so the density detection effect of the entire width area is more consistent. Attached Figure Description

[0017] Figure 1 is a three-dimensional structural diagram of the present invention;

[0018] Figure 2 is a schematic diagram of the detection unit structure of the present invention.

[0019] In the diagram: 1. Detection unit; 101. X-ray source; 102. Collimation; 103. Linear array detector. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. In this description, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, in this description, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0021] During the full surface density inspection, the strip of material to be tested continuously passes between the X-ray source and the linear array detector. The X-ray source emits X-rays downwards, and the linear array detector receives the intensity of the X-rays that penetrate the material to be tested and reach the linear array detector, thus achieving full surface density inspection. In this invention, the belt direction refers to the direction of movement of the material to be tested, and the width direction refers to the width direction of the material to be tested.

[0022] Please refer to Figures 1-2. An embodiment of the present invention is provided: a surface density full inspection mechanism, including several groups of inspection units 1 distributed along the direction of the inspection material, and each group of inspection units 1 is arranged on the same straight line along the width direction of the inspection material. Two adjacent inspection units 1 in the width direction of the inspection material are located on different straight lines. The effective inspection width of the several inspection units 1 covers the width of the inspection material. In this embodiment, two groups of inspection units 1 are provided. The two groups of inspection units 1 are arranged on two straight lines along the width direction of the inspection material. The inspection units 1 on the two straight lines are arranged at intervals in the width direction of the inspection material to avoid mutual interference between the inspection units 1.

[0023] The detection units 1 have the same structure, and each detection unit 1 includes a radiation source 101, a collimator 102 installed at the bottom of the radiation source 101, and a linear array detector 103 located directly below the collimator 102. The collimator 102 is used to confine the radiation emitted by the radiation source 101 into a fan-shaped beam. The fan-shaped beam illuminates the linear array detector 103 and produces a long strip of light spot. The long strip of light spot covers the length of the linear array detector 103. The linear array detector 103 is used to receive the radiation from the radiation source 101.

[0024] Several X-ray sources 101 and collimators 102 are fixed in the same housing, and several linear array detectors 103 are fixed in the same housing. A gap is reserved between the two housings to accommodate the material to be tested. The height planes of the X-ray sources 101 and the linear array detectors 103 are parallel to the plane of the material to be tested.

[0025] Specifically, the effective detection widths of several detection units 1 are connected end-to-end in the width direction of the detection material, and the sum of the effective detection widths of detection units 1 is greater than the width of the detection material. In the actual detection process, the detection material passes between the X-ray source 101 and the linear array detector 103. There is a height difference between the detection material and the linear array detector 103. Referring to Figure 2, due to the amplification effect of the fan-shaped beam, the lengths irradiated on the detection material and the linear array detector 103 are not the same. The effective detection width of a single detection unit 1 on the detection material is w. To determine the actual width to be detected by the linear array detector 103 under a given geometric relationship, the distance from the focal point of the X-ray source 101 to the detection material is L1, and the distance from the focal point of the X-ray source 101 to the linear array detector 103 is L2. Then the magnification ratio M = L2 / L1. The specific structure of the linear array detector 103 is existing technology and will not be described in detail here. In this embodiment, it includes n pixel detectors arranged along the width direction of the detection material. The length of a single pixel detector is a, and the length of the linear array detector 103 of a single detection unit 1 is n*a. Then the effective detection width w = (n*a) / M.

[0026] The X-ray source 101 and the linear array detector 103 are in one-to-one correspondence, and the fan-shaped beam of any X-ray source 101 will not irradiate the other linear array detectors 103.

[0027] In this embodiment, several radiation sources 101 have the same size and structure and are all located on the same height plane, several linear array detectors 103 have the same size and structure and are also located on the same height plane, and the effective detection width of the detection unit 1 is equal.

[0028] In one embodiment, the detection unit 1 can also be set to different sizes as needed, just to ensure that the effective detection widths of two adjacent detection units 1 are connected end to end;

[0029] In one embodiment, several X-ray sources 101 are located at different heights, and several linear array detectors 103 are located at the same height. Since the X-ray source 101 emits a fan-shaped beam, by adjusting its height or fan beam angle, and in conjunction with the corresponding length of the linear array detector 103, the length of the light spot irradiating the detection material (i.e., the effective detection width of the detection unit 1) can be adjusted to ensure that the effective detection widths of two adjacent detection units 1 are connected end to end.

[0030] In this embodiment, a total of N detection units 1 are provided. In order to meet the requirement of full detection of surface density, the total detection width of detection unit 1 is N*w > the width of the detection material W. When the effective detection width w of detection unit 1 is not the same, w1+w2+…+wN>W.

[0031] Before actual measurement, each pixel detector of the linear array detector 103 is calibrated using a sample of the surface density gradient of the target material. After calibration, a full surface density line scan is performed. Then, the two-dimensional surface density distribution data obtained from the full line scan is further processed. First, the surface density data obtained by the detection unit 1, which is distributed on two straight lines, is aligned in the direction of the tape. Then, based on the magnification ratio, the actual width of the detected material is obtained.

[0032] It will be apparent 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 invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A surface density full inspection testing mechanism, characterized in that: It includes several groups of detection units (1) distributed along the direction of the detection material, and each group of detection units (1) is arranged on the same straight line along the width direction of the detection material. Two adjacent detection units (1) in the width direction of the detection material are located on different straight lines, and the effective detection width of the several detection units (1) covers the width of the detection material.

2. The areal density full inspection testing mechanism according to claim 1, characterized in that: The effective detection widths of several detection units (1) are connected end to end in the width direction of the detection material, and the sum of the effective detection widths of the detection units (1) is greater than the width of the detection material.

3. The areal density full inspection testing mechanism according to claim 1, characterized in that: The detection units (1) have the same structure, and each detection unit (1) includes a radiation source (101), a collimator (102) installed at the bottom of the radiation source (101), and a linear array detector (103) set directly below the collimator (102). The collimator (102) is used to constrain the radiation emitted by the radiation source (101) into a fan-shaped beam. The fan-shaped beam illuminates the linear array detector (103) to produce a long strip of light spot, and the long strip of light spot covers the length of the linear array detector (103). The linear array detector (103) is used to receive the radiation from the radiation source (101).

4. The areal density full inspection testing mechanism according to claim 3, characterized in that: Several X-ray sources (101) and collimators (102) are fixed in the same housing, and several linear array detectors (103) are fixed in the same housing. A gap is reserved between the two housings to accommodate the material to be tested. The height planes of the X-ray sources (101) and linear array detectors (103) are parallel to the plane of the material to be tested.

5. The areal density full inspection testing mechanism according to claim 3, characterized in that: The X-ray source (101) and the linear array detector (103) are in one-to-one correspondence, and the fan-shaped beam of any X-ray source (101) will not irradiate the other linear array detectors (103).

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