Pole piece detection instrument

Abstract

The utility model relates to a pole piece detection instrument which comprises a base; the bracket is movably arranged on the base; the driving mechanism is mounted on the base and used for driving the bracket to move on the base; the position measuring device is used for detecting position information of the driving mechanism; the driving control system is electrically connected with the driving mechanism and the position measuring device, and is used for controlling the operation of the driving mechanism and receiving the position information; the pole piece detection mechanism is fixed on the bracket and is used for detecting pole piece information; the pole piece boundary detection mechanism is fixed on the pole piece detection mechanism and is used for detecting the boundary position information of the pole piece; and the pole piece detection system has the function of calculating the boundary position of the pole piece, receives the position information, the pole piece information and the boundary position information of the pole piece, and outputs control information to the driving control system, or the pole piece detection system receives the pole piece information, and the driving control system has the function of calculating the boundary position of the pole piece. The pole piece detection instrument can detect the boundary position of the pole piece in real time and with high precision.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium battery detection, and more specifically to a pole piece detection instrument. Background Art

[0002] Lithium batteries have outstanding advantages such as high energy density, long service life, high rated voltage, high power, extremely low self-discharge rate, light weight, strong adaptability to high and low temperatures, and green environmental protection. With the development of technology, lithium batteries have become one of the mainstream batteries and are the best power source for mobile electronic devices, electric vehicles and various electronic products.

[0003] Lithium-ion batteries are mainly composed of positive and negative electrodes, electrolytes, separators, tabs, and packaging shells. During the production and testing of positive and negative electrodes, the measurement accuracy of the electrode boundary position will directly affect the electrode production effect, thereby affecting the performance of the final battery product. Therefore, it is necessary to improve the detection accuracy of the electrode boundary to ensure good electrode detection results and improve the yield rate of lithium battery production.

[0004] At present, the commonly used methods for detecting the boundary of the pole piece include image detection and photoelectric detection. Image detection is mainly based on image recognition algorithm. The edge position image is obtained through CCD or CMOS image sensor. After being processed by image recognition algorithm, the edge position, shape and other parameters are calculated. The advantage of image detection is that it can obtain more information about the boundary of the pole piece, and can realize the functions of detecting the pole piece and detecting the boundary position of the pole piece at the same time. The disadvantages of image detection are that the algorithm is more complicated and occupies more computer resources; it is easily affected by factors such as light, and the anti-interference ability is poor; the accuracy of real-time detection of the boundary position of the pole piece is not high.

[0005] Photoelectric detection mainly uses photoelectric sensors to detect the boundary position of the pole piece, and obtains the boundary position of the pole piece by judging the change of the receiver signal of the through-beam or reflective photoelectric sensor. The advantages of photoelectric detection are high cost performance, simplicity and ease of use, and high static detection accuracy; the disadvantage is low dynamic accuracy.

[0006] At present, in the production and inspection process of pole pieces, it is necessary to avoid the problem of poor accuracy of dynamic detection of pole piece boundary position. When using photoelectric detection of pole piece boundary position, static detection of pole piece boundary position is performed before correction, cutting and other operations. When using image detection, dynamic detection obtains rough pole piece boundary position, and static detection obtains high-precision pole piece boundary information.

[0007] The existing electrode boundary detection technology has poor dynamic accuracy and cannot meet the high-precision requirements of real-time electrode detection, resulting in poor electrode detection results. Static detection of electrode boundaries will affect the electrode detection efficiency and electrode production efficiency, thereby affecting the production efficiency of lithium batteries. Utility Model Content

[0008] The technical problem to be solved by the utility model is to provide a pole piece detection instrument capable of detecting the pole piece boundary position in real time and with high precision in view of the above-mentioned defects of the prior art.

[0009] The technical solution adopted by the utility model to solve the technical problem is: constructing a pole piece detection instrument, including:

[0010] Base;

[0011] A bracket, movably disposed on the base;

[0012] A driving mechanism, mounted on the base, for driving the bracket to move on the base;

[0013] A position measuring device, used to detect the position information of the driving mechanism;

[0014] A drive control system, electrically connected to the drive mechanism and the position measuring device, respectively, for controlling the operation of the drive mechanism and receiving the position information;

[0015] A pole piece detection mechanism, fixed on the bracket, for detecting pole piece information;

[0016] A pole piece boundary detection mechanism, fixed on the pole piece detection mechanism, for detecting pole piece boundary position information; and

[0017] A pole piece detection system having the function of calculating the pole piece boundary position, wherein the pole piece detection system receives the position information, pole piece information and pole piece boundary position information, and outputs control information to the drive control system; or the pole piece detection system receives the pole piece information, and the drive control system has the function of calculating the pole piece boundary position.

[0018] In some embodiments, the pole piece detection system is respectively connected to the pole piece detection mechanism, the pole piece boundary detection mechanism, and the drive control system.

[0019] In some embodiments, the pole piece detection system has the function of calculating the pole piece boundary position, the pole piece detection system receives the position information, pole piece information and pole piece boundary position information, and outputs control information to the drive control system, and the pole piece detection system is respectively connected to the pole piece detection mechanism, the pole piece boundary detection mechanism and the drive control system network.

[0020] In some embodiments, the pole piece detection system receives the pole piece information, the drive control system has the function of calculating the pole piece boundary position, the pole piece detection system is respectively connected to the pole piece detection mechanism and the drive control system network, and the pole piece boundary detection mechanism is electrically connected to the drive control system.

[0021] In some embodiments, the driving mechanism includes a driving motor, a lead screw, a lead screw nut and a guide rail.

[0022] The drive motor is electrically connected to the drive control system, the lead screw is connected to the drive motor, the lead screw nut is threadedly connected to the lead screw and the bracket, and the bracket is limited to move on the guide rail.

[0023] When the driving control system controls the driving motor to operate, the driving motor rotates to move the lead screw nut along the lead screw, thereby driving the bracket to move along the guide rail.

[0024] In some embodiments, the position measurement device includes an encoder, and the encoder is fixed on the drive motor.

[0025] In some embodiments, the bracket includes a bracket base movably disposed on the guide rail and a bracket body fixed on the bracket base, and the pole piece detection mechanism is fixed on the bracket body.

[0026] In some embodiments, the pole piece information detected by the pole piece detection mechanism includes pole piece thickness and pole piece thinning area data, and the position information includes the current operating position, current operating speed, and current operating direction of the driving mechanism.

[0027] In some embodiments, the pole piece detection mechanism includes a first pole piece detection device and a second pole piece detection device.

[0028] The first pole piece detection device and the second pole piece detection device are respectively fixed at the upper end and the lower end of the bracket, and detect the pole piece information from upper and lower directions respectively.

[0029] In some embodiments, the pole piece boundary detection mechanism is fixed on the first pole piece detection device or the second pole piece detection device.

[0030] The implementation of the utility model has at least the following beneficial effects: the pole piece boundary detection mechanism is fixed on the pole piece detection mechanism and can move with the pole piece detection mechanism, dynamically detect the pole piece boundary position, and ensure the real-time acquisition of the pole piece boundary position; the position measurement device can ensure that the calculated pole piece boundary position has high accuracy; the pole piece detection system controls the driving mechanism according to the pole piece boundary position to adjust the start and end positions of the detection, which not only improves the detection accuracy of the pole piece detection system, but also improves the detection efficiency of the pole piece detection instrument and the pole piece production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0032] Figure 1 It is an overall structural diagram of a pole piece detection instrument in some embodiments of the utility model;

[0033] Figure 2 yes Figure 1 A top view of the pole piece detection instrument shown;

[0034] Figure 3 yes Figure 1 The partial structural diagram of the pole piece detection instrument shown;

[0035] Figure 4 yes Figure 1 The partial structure diagram of the pole piece detection instrument when detecting the pole piece shown;

[0036] Figure 5 It is a structural block diagram of a pole piece detection instrument in some embodiments of the utility model;

[0037] Figure 6 It is a schematic diagram of the starting and ending strokes of the driving mechanism in some embodiments of the utility model;

[0038] Figure 7 It is a fitting curve diagram of the sampling data of the pole piece in some embodiments of the utility model;

[0039] Figure 8 is a flow chart of pole piece boundary position detection in some embodiments of the utility model;

[0040] Fig. 9 It is a structural block diagram of a pole piece detection instrument in other embodiments of the utility model;

[0041] Fig.10 It is a flow chart of pole piece boundary position detection in other embodiments of the utility model. DETAILED DESCRIPTION

[0042] In order to have a clearer understanding of the technical features, purposes and effects of the utility model, the specific implementation of the utility model is now described in detail with reference to the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0043] In the description of the present utility model, it should be understood that 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 technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0044] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] Figures 1 to 5 The pole piece detection instrument 100 in some embodiments of the utility model is shown, and the pole piece detection instrument 100 includes a base 1, a driving mechanism 2, a position measuring device 3, a bracket 4, a pole piece detection mechanism 5, a pole piece boundary detection mechanism 6, a driving control system 7 and a pole piece detection system 8. Among them, the driving mechanism 2, the position measuring device 3, the pole piece detection mechanism 5, the pole piece boundary detection mechanism 6, and the driving control system 7 are all located at the acquisition end 101 of the pole piece detection instrument 100, and the pole piece detection system 8 is located at the control end 102 of the pole piece detection instrument 100.

[0046] The bracket 4 is arranged on the base 1 so as to be movable back and forth. The driving mechanism 2 is installed on the base 1 and connected to the bracket 4, and is used to drive the bracket 4 to move on the base 1. The position measuring device 3 is used to detect the position information of the driving mechanism 2, and it can be installed on the driving mechanism 2, the bracket 4 or the pole piece detection mechanism 5. The driving control system 7 is electrically connected to the driving mechanism 2 and the position measuring device 3 respectively, and is used to control the operation of the driving mechanism 2, and can obtain the position information of the driving mechanism 2 through the position measuring device 3. The pole piece detection mechanism 5 is fixed on the bracket 4 and can move with the bracket 4 on the base 1, and is used to detect the pole piece information. The pole piece boundary detection mechanism 6 is fixed on the pole piece detection mechanism 5, and is used to detect the pole piece boundary position information. The pole piece detection system 8 is connected to the pole piece detection mechanism 5, the pole piece boundary detection mechanism 6, and the driving control system 7 respectively, and has the function of calculating the pole piece boundary position.

[0047] According to actual detection needs, the base 1, the driving mechanism 2, the position measuring device 3, the bracket 4, the pole piece detection mechanism 5, and the pole piece boundary detection mechanism 6 having various structural forms can be used.

[0048] In some embodiments, the drive mechanism 2 may include a drive motor 21, a screw 23, a screw nut and a guide rail 25. The drive control system 7 is electrically connected to the drive motor 21, and is used to control the operation of the drive motor 21, such as controlling the rotation direction and rotation speed of the drive motor 21. The screw 23 is connected to the drive motor 21, and the screw nut is threadedly connected to the screw 23 and the connecting bracket 4, and the bracket 4 is limited to move in the guide rail 25, such as the bracket 4 is slidably connected to the guide rail 25. Here, the screw 23 and the guide rail 25 are arranged in parallel, and the threaded connection between the screw nut and the screw 23 is used to realize the conversion between rotational motion and linear motion.

[0049] Specifically, when the drive control system 7 controls the drive motor 21 to operate, the drive motor 21 rotates to make the lead screw nut move along the lead screw 23, thereby driving the bracket 4 to move along the guide rail 25. The lead screw 23 drives the bracket 4 to move synchronously along the guide rail 25. The pole piece detection mechanism 5 fixed on the bracket 4 and the pole piece boundary detection mechanism 6 fixed on the pole piece detection mechanism 5 also move synchronously along the guide rail 25.

[0050] In some embodiments, the driving mechanism 2 may further include a screw connecting seat 22 and a screw fixing seat 24. The screw connecting seat 22 is used to connect the driving motor 21 and the screw 23. The screw fixing seat 24 is used to fix the screw 23 to ensure the stable operation of the driving mechanism 2. The driving mechanism 2 has the advantages of stable operation and strong applicability.

[0051] In some embodiments, the position measurement device 3 includes an encoder 31, which can be fixed on the drive motor 21 and electrically connected to the drive control system 7, and is used to obtain the position of the drive motor 21. The encoder 31 can accurately record the current position and movement direction of the drive mechanism 2, and obtain the current running speed of the drive mechanism 2, and has the characteristics of simple installation and convenient operation, and can ensure that the calculated pole piece boundary position has a high accuracy.

[0052] Specifically, the drive motor 21 equipped with the encoder 31 generates a certain number of pulse signals after one rotation, and the number of rotations of the drive motor 21 can be calculated based on the total number of pulse signals moving from the origin to a certain position. According to the lead of the screw 23, that is, the distance the screw 23 moves straight after the drive motor 21 rotates one circle, the position information of the pole piece detection mechanism 5 can be calculated. Similarly, according to the number of pulse signals generated by the encoder 31 per unit time, combined with the lead of the screw 23, the speed information of the pole piece detection mechanism 5 can be calculated.

[0053] It can be understood that in other embodiments, the position measuring device 3 can also use other known detection devices to obtain the position, speed, movement direction and other information of the pole piece detection mechanism 5. For example, the position measuring device 3 can also use a magnetic scale, a grating scale, an electromagnetic induction sensor, a potentiometric displacement sensor, a Hall displacement sensor or other displacement sensors.

[0054] For example, as an alternative, the position measurement device 3 may include a magnetic scale and a reading head. The magnetic scale is fixed beside the guide rail 25, and the reading head is fixed on the pole piece detection mechanism 5. The reading head follows the movement of the pole piece detection mechanism 5, and obtains information such as the position and speed of the pole piece detection mechanism 5 in real time based on the signal read from the magnetic scale. Specifically, the magnetic scale records the magnetization signal of equal spacing in advance, and when the reading head passes through the magnetic scale, it obtains the periodic magnetic field strength signal and converts it into an electrical signal. The speed and position information can be calculated based on the total number of pulses of the electrical signal and the number of pulses per unit time.

[0055] The bracket 4 may include a bracket base 41 and a bracket body 42 fixed on the bracket base 41. The bracket base 41 is fixed on the driving mechanism 2, and the bracket body 42 is connected to the driving mechanism 2 through the bracket base 41. The bracket base 41 is used to ensure that the bracket body 42 follows the movement of the driving mechanism 2.

[0056] The support base 41 may include a support support seat 411 and a guide rail connection seat 412. The guide rail connection seat 412 is used to connect the guide rail 25 and the support support seat 411. The support support seat 411 is used to support the support body 42.

[0057] In some embodiments, the support body 42 may be a large C-shaped support, which may include an upper support 421 and a lower support 422 disposed vertically. A through hole is formed between the upper support 421 and the lower support 422 for the pole piece 9 to pass through.

[0058] The pole piece detection mechanism 5 may include a first pole piece detection device 51 and a second pole piece detection device 52, which are respectively fixed on the upper bracket 421 and the lower bracket 422, and are both connected to the pole piece detection system 8 network. The pole piece 9 passes between the first pole piece detection device 51 and the second pole piece detection device 52 to achieve non-destructive detection of the pole piece 9. The first pole piece detection device 51 and the second pole piece detection device 52 both move at the same time, and obtain information of the pole piece 9 from the upper and lower directions respectively, and have the advantages of high synchronization and high precision. Here, the information obtained by the first pole piece detection device 51 and the second pole piece detection device 52 includes but is not limited to one or more of the thickness of the pole piece 9, the thinning area data, etc., and different information can be collected by selecting appropriate sensors to meet the collection requirements.

[0059] The pole piece boundary detection mechanism 6 is fixed on the pole piece detection mechanism 5 and can follow the movement of the pole piece detection mechanism 5, dynamically detect the pole piece boundary position, and ensure the real-time acquisition of the pole piece boundary position. In some embodiments, the pole piece boundary detection mechanism 6 can be fixed at the first pole piece detection device 51 for easy debugging. Specifically, the pole piece boundary detection mechanism 6 may include a pole piece boundary detection device 61, a pole piece boundary detection device connecting seat 62, and a pole piece boundary detection device detection range 63. The pole piece boundary detection device 61 is fixed to the first pole piece detection device 51 through the pole piece boundary detection device connecting seat 62, and follows the movement of the first pole piece detection device 51. Of course, in other embodiments, the pole piece boundary detection device 61 can also be fixed to the second pole piece detection device 52 through the pole piece boundary detection device connecting seat 62.

[0060] The pole piece boundary detection device 61 is electrically connected to the drive control system 7. Exemplarily, the pole piece boundary detection device 61 may adopt a reflective photoelectric sensor, which has the characteristics of simple operation, low cost, and wide application range.

[0061] The detection range 63 of the pole piece boundary detection device passes through the pole piece 9, but does not reach the second pole piece detection device 52. Before the detection of this embodiment begins, if the detection range 63 of the pole piece boundary detection device reaches the second pole piece detection device 52, the pole piece boundary detection mechanism 6 will mistakenly identify the second pole piece detection device 52 as the pole piece 9, and the pole piece boundary detection mechanism 6 needs to be manually adjusted to reduce its detection range; if the detection range 63 of the pole piece boundary detection device does not reach the pole piece 9, the pole piece boundary detection mechanism 6 will be unable to detect the pole piece 9, and the pole piece boundary detection mechanism 6 needs to be manually adjusted to increase its detection range.

[0062] It can be understood that when the pole piece boundary detection device 61 moves along the width of the pole piece 9 with the pole piece detection mechanism 5, it will pass through the pole piece 9 and move from the first side boundary of the pole piece 9 to the second side boundary. On the one hand, the detection range 63 of the pole piece boundary detection device passes through the pole piece 9 but does not reach the second pole piece detection device 52, which can prevent misidentification. On the other hand, when the pole piece boundary detection device 61 moves from the first side boundary of the pole piece 9 to the second side boundary, the pole piece boundary detection device 61 sends a first trigger signal when the first side boundary is detected, and the position information of the first side boundary measured this time can be obtained by reading the information of the encoder 31 at this time; similarly, the pole piece boundary detection device 61 sends a second trigger signal when the second side boundary is detected, and the position information of the second side boundary measured this time can be obtained by reading the information of the encoder 31 at this time. By controlling the pole piece boundary detection device 61 to reciprocate n times, after removing the abnormal data, the average value is obtained, and it can be considered that the accurate boundary position information of the pole piece 9 is obtained.

[0063] In this embodiment, the pole piece detection system 8 can obtain the pole piece information detected by the pole piece detection mechanism 5 in real time through the network connection with the pole piece detection mechanism 5. At the same time, through the network connection between the pole piece detection system 8 and the drive control system 7 and the electrical connection between the drive control system 7 and the drive motor 21 and the encoder 31, the pole piece detection system 8 can obtain the current running position, current running speed, current running direction and other information in real time. Through the network connection between the pole piece detection system 8 and the pole piece boundary detection device 61 of the pole piece boundary detection mechanism 6, the pole piece detection system 8 can obtain the position information from the encoder 31 according to the signal change of the pole piece boundary detection device 61, thereby calculating the real-time and high-precision pole piece boundary position.

[0064] The pole piece detection system 8 can also control the starting and ending positions of the movement of the driving mechanism 2 according to the pole piece boundary position, thereby adjusting the starting and ending positions of the movement of the pole piece detection mechanism 5, which can not only improve the detection accuracy of the pole piece detection system 8, but also improve the detection efficiency and pole piece production efficiency of the pole piece detection instrument 100, which is conducive to the promotion and use of the pole piece detection instrument 100 in the field of lithium battery pole piece production.

[0065] The specific description of the pole piece detection system 8 controlling the driving mechanism 2 to adjust the start and end positions of the detection according to the pole piece boundary position is as follows:

[0066] In this embodiment, when the pole piece detection instrument 100 operates normally, the pole piece 9 runs along the second direction Y, and the pole piece detection mechanism 5 runs back and forth along the first direction X. The first direction X is a direction parallel to the guide rail 25, the second direction Y is a direction parallel to the pole piece 9, and the first direction X is perpendicular to the second direction Y.

[0067] During the first operation, the pole piece detection mechanism 5 moves along the first direction X from a preset origin to a preset end point, and then from the preset end point to a preset origin;

[0068] When the pole piece detection mechanism 5 moves to the pole piece boundary position, the pole piece boundary detection device 61 signal changes from no to yes, and the pole piece detection system 8 receives the signal change of the pole piece boundary detection device 61, obtains the pulse signal of the encoder 31, calculates the position here, and records it as the first pole piece boundary position;

[0069] When the pole piece detection mechanism 5 leaves the pole piece boundary position, the pole piece boundary detection device 61 signal changes from on to off, and the pole piece detection system 8 receives the signal change of the pole piece boundary detection device 61, obtains the pulse signal of the encoder 31, calculates the position here, and records it as the second pole piece boundary position;

[0070] The pole piece detection system 8 calculates the pole piece width according to the first pole piece boundary position and the second pole piece boundary position, and calculates the average pole piece width after multiple round trips. According to the calculated average pole piece width, the origin and end point positions detected by the pole piece detection mechanism 5 are readjusted.

[0071] Generally, the distance between the preset origin position and the preset end position of the pole piece detection mechanism 5 is 2m to 3m, and the actual pole piece width to be measured is 40cm to 80cm. After readjusting the origin and end point of the pole piece detection mechanism 5, the detection efficiency and detection accuracy of the pole piece detection instrument 100 will be improved.

[0072] Combination Figure 6 For explanation, the initial origin of the pole piece detection mechanism 5 is A, and the initial end point is B. After multiple round trips, the boundaries of the pole piece are A' and B'. In the measurement of the traditional pole piece detection mechanism 5, since the traditional pole piece detection mechanism 5 needs to pass through and measure the A-A' part and the B-B' part respectively, passing through and measuring the above two parts increases the moving time of the pole piece detection mechanism 5 on the one hand, and on the other hand, the pole piece detection mechanism 5 collects extra data, which undoubtedly increases the amount of data analysis and processing, resulting in an increase in calculation time and calculation cost. These two aspects jointly affect the accuracy and timeliness of the entire pole piece measurement.

[0073] In this embodiment, the origin of the pole piece detection mechanism 5 is adjusted to A' and the end point is adjusted to B', thereby shortening the operation path of the pole piece detection mechanism 5 and reducing the collection of redundant data, thereby effectively improving the accuracy and timeliness of the entire pole piece measurement.

[0074] However, if the origin of the pole piece detection mechanism 5 is adjusted to A' and the end point is adjusted to B', then the driving mechanism 2 starts and stops directly at A' and B'. Since the linear motion process of the driving mechanism 2 involves the processes of acceleration, uniform speed, and deceleration, the pole piece detection mechanism 5 performs effective data sampling on the pole piece throughout the entire process from the start to the stop of the driving mechanism 2.

[0075] Furthermore, it takes time for the drive mechanism 2 to move to a specific speed and stop from a specific speed, that is, it takes time for the drive mechanism 2 to accelerate and decelerate. The above design lacks a buffer zone during the acceleration and deceleration process, and the sampling frequency of the pole piece detection mechanism 5 is certain, which will cause the sampling points on A'B' to be dense (acceleration), sparse (uniform speed), and dense (deceleration). In fact, in order to ensure the consistency of the detection of each part of the pole piece, the pole piece detection mechanism 5 is preferably at a uniform speed to complete A'B'.

[0076] In view of the above defects, this embodiment proposes the following optimization methods:

[0077] P1: Take A'-A0 as the new starting point, where A0 is the stroke required for the driving mechanism 2 to accelerate from zero to a preset uniform speed, and take B'+B0 as the new end point, where B0 is the stroke required for the driving mechanism 2 to decelerate from a preset uniform speed to zero. In this way, the pole piece detection mechanism 5 can always be at a uniform speed during the process of collecting data on the pole piece, ensuring the consistency of the sampling density of each point on the pole piece.

[0078] Furthermore, considering that there are thinning areas on both sides of the pole piece width, the thinning area is more complicated than the middle area. Figure 7 As shown in the figure, taking the surface density data detection as an example, the arrow segment is the sampling data of the thinning area. The data points in the thinning area are often irregular. More dense sampling data can better fit the real curve, that is, a denser sampling density is more suitable for analyzing the thinning area. To solve the problem of the thinning area, optimization can be performed in the following ways:

[0079] P2: Assuming that the width of the thinning area of ​​the pole piece corresponding to the acceleration section is A1, and the width of the thinning area of ​​the deceleration section is B1, A1 is compensated to the starting point to obtain A'-A0+A1, so that the pole piece detection mechanism 5 can obtain more sampling data for the thinning area of ​​the acceleration section for subsequent analysis. Similarly, B1 is compensated to the end point to obtain B'-B0+B1, so that the pole piece detection mechanism 5 can obtain more sampling data for the thinning area of ​​the deceleration section for subsequent analysis.

[0080] In other embodiments, the thinning zone problem can also be optimized in the following ways: on the basis of P1, when the driving mechanism 2 passes through the thinning zones on both sides at a preset uniform speed, the sampling frequency of the pole piece detection mechanism 5 can be increased to obtain more detection data in the thinning zone relative to the middle area.

[0081] The pole piece detection system 8 of the utility model controls the driving mechanism 2 to adjust the start and end positions of the detection according to the pole piece boundary position, which not only improves the detection accuracy of the pole piece detection system 8, but also improves the detection efficiency and pole piece production efficiency of the pole piece detection instrument 100, which is beneficial to the promotion and use of the pole piece detection instrument 100 in the field of lithium battery pole piece production.

[0082] The pole piece detection system 8 has the function of calculating the pole piece boundary position, and the pole piece detection system 8 receives the position information, pole piece information and pole piece boundary position information, and outputs the control information to the drive control system 7. Figure 5As shown, the pole piece detection mechanism 5, the pole piece boundary detection mechanism 6, and the drive control system 7 located at the acquisition end 101 are respectively connected to the pole piece detection system 8 located at the control end 102 through a network, and the encoder 31 is electrically connected to the drive control system 7. The network connection has a certain delay, while the delay of the electrical connection is very small and can be ignored. When the pole piece detection mechanism 5 runs back and forth at a low speed to detect the pole piece, the delay of the network connection causes the detection error of the pole piece boundary position to be low and within the allowable range. When the pole piece detection mechanism 5 runs back and forth at a high speed to detect the pole piece, the delay of the network connection causes the detection error of the pole piece boundary position to increase with the increase of the running speed.

[0083] like Figure 8 As shown, in some embodiments, the method for obtaining the boundary position of the pole piece includes the following steps:

[0084] S11, the pole piece boundary detection mechanism 6 detects the pole piece boundary position and sends a signal;

[0085] S12, the pole piece detection system 8 receives a signal sent by the pole piece boundary detection mechanism 6 through a network connection;

[0086] S13, the pole piece detection system 8 runs the program according to the signal and calls the relevant instructions;

[0087] S14, the pole piece detection system 8 sends a command to the drive control system 7;

[0088] S15, the drive control system 7 receives the instruction;

[0089] S16, the drive control system 7 obtains the pole piece boundary position information by reading the signal of the encoder 31, and sends it to the pole piece detection system 8;

[0090] S17, the pole piece detection system 8 receives the pole piece boundary position information and calculates the pole piece boundary position.

[0091] It should be noted that the signal change of the electrode edge detection mechanism 6 in step S11 does not refer to signal abnormality, but refers to a change from no electrode detection to detection of the electrode, or from detection of the electrode to no electrode detection; the positions of these two signal changes are the boundary positions of the electrode. In other words, the electrode edge detection mechanism 6 is triggered by the presence or absence of the object to be detected to detect.

[0092] In the process of obtaining the first pole piece boundary position, in step S11, the pole piece boundary detection mechanism 6 changes from not detecting the pole piece to detecting the pole piece, this moment is recorded as T0, the moment of sending the signal is recorded as T1, and the response delay of the pole piece boundary detection mechanism 6 itself is recorded as d0; in step S12, the moment when the pole piece detection system 8 receives this signal through the network connection is recorded as T2, and the network delay is recorded as d1; in step S14, the moment when the pole piece detection system 8 sends the instruction is recorded as T3, and the running program delay in steps S13 and S14 is recorded as d2; in step S15, the moment when the drive control system 7 receives the instruction is recorded as T4, and the network delay between the drive control system 7 and the pole piece detection system 8 in step S15 is recorded as d3; in step S16, the moment when the drive control system 7 receives the signal from the encoder 31 is recorded as T5, and the response time of the encoder 31 and the electrical connection delay between the drive control system 7 and the encoder 31 in step S16 are recorded as d4. Since the pole piece boundary position information has been acquired in step S16, the network delay between the pole piece detection system 8 and the drive control system 7 in step S17 does not affect the accuracy of the pole piece boundary position information.

[0093] The only difference between obtaining the second pole piece boundary position and obtaining the first pole piece boundary position is that the pole piece boundary detection mechanism 6 changes from detecting the pole piece to not detecting the pole piece, and the subsequent steps are exactly the same.

[0094] After receiving multiple first pole piece boundary positions and second pole piece boundary positions, the pole piece detection system 8 calculates the average first pole piece boundary position and second pole piece boundary position after excluding obviously erroneous values, and then changes the origin and end point positions of the pole piece detection mechanism 5.

[0095] In this embodiment, the response time d0 of the pole piece boundary detection mechanism 6 in step S11 is within 1ms and can be ignored. The response time of the encoder 31 and the electrical connection delay d4 with the drive control system 7 in step S16 are much less than 1ms and can be ignored. The network connection delay d1 between the pole piece detection system 8 and the pole piece boundary detection mechanism 6 in step S12, the running program delay d2 of the pole piece detection system 8 in steps S13 and S14, and the network connection delay d3 between the pole piece detection system 8 and the drive control system 7 in steps S14, S15 and S16 are the main factors affecting the pole piece boundary detection error.

[0096] It is understandable that the accuracy error is mainly caused by the delay of network transmission and the processing time of the pole piece detection system 8.

[0097] Through actual operation detection experiments, when the operating speed of the pole piece detection instrument 100 is 12m / min, the boundary position data fluctuates within the interval of 0.1mm, and the proportion is significantly less than half. It can be concluded that when the operating speed is 12m / min, the detection error of the pole piece boundary position does not exceed 0.05mm. When the operating speed of the pole piece detection instrument 100 is 20m / min, the boundary position data fluctuates within the interval of 0.1mm, and the proportion is significantly more than half. It can be concluded that when the operating speed is 20m / min, the detection error of the pole piece boundary position is between 0.05mm and 0.1mm.

[0098] It is worth noting that, in order to control variables, the pole piece is fixed on the pole piece detection instrument 100 in this experiment to prevent the displacement caused by the movement of the pole piece itself from affecting the experimental results.

[0099] In addition, the detection error increases with the speed because of the network delay and the delay of the program running time (because the program runs cyclically, the delay is about a few milliseconds).

[0100] In other embodiments, when the error exceeds 0.1 mm, it can be compensated by a program algorithm, but the algorithm compensation effect is limited, and compensating the pole piece boundary position may cause the pole piece detection information accuracy to decrease, so it is generally not used in actual use. In addition, the error of the pole piece boundary detection device in this experiment is less than 0.1 mm, and there is no need to use algorithm compensation, so algorithm compensation is not mentioned here.

[0101] In order to further improve the detection accuracy of the pole piece boundary position, the utility model also provides a further improvement scheme of the pole piece detection technology: the pole piece detection system 8 is connected to the pole piece detection mechanism 5 and the drive control system 7 respectively, the pole piece boundary detection mechanism 6 is connected to the drive control system 7, and the pole piece boundary detection mechanism 6 has the function of calculating the pole piece boundary position. Fig. 9 As shown, the encoder 31 is directly electrically connected to the drive control system 7. Through the electrical connection between the drive control system 7 and the encoder 31 and the pole piece boundary detection mechanism 6, the drive control system 7 located at the acquisition end 101 can directly obtain the position information of the encoder 31, and then send the position information of the encoder 31 to the pole piece detection system 8 through the network connection between the drive control system 7 and the pole piece detection system 8, so that the detection of the pole piece boundary position is no longer affected by the delay of the network connection.

[0102] In this embodiment, the drive control system 7 reads the signal of the pole piece boundary detection mechanism 6 to obtain the position information of the encoder 31. The premise of this optimization is that the drive control system 7 has the function of calculating the pole piece boundary position. If it does not have this function, it can only be as follows Figure 5As shown, it is executed by the instruction of the pole piece detection system 8; or by converting the signal of the pole piece boundary detection mechanism 6 into a signal that can be recognized by the drive control system 7.

[0103] like Fig.10 As shown, in the improved solution of this embodiment, obtaining the boundary position of the pole piece includes the following steps:

[0104] S21, the pole piece boundary detection mechanism 6 detects the pole piece boundary position and sends a signal;

[0105] S22, the drive control system 7 receives a signal sent by the pole piece boundary detection mechanism 6 through electrical connection;

[0106] S23, the drive control system 7 obtains position information by reading the signal of the encoder 31, calculates the boundary position of the pole piece, and sends it to the pole piece detection system 8;

[0107] S24, the pole piece detection system 8 receives the pole piece boundary position.

[0108] In the improved scheme of the present embodiment, the response time of the pole piece boundary detection mechanism 6 in step S21 is within 1ms and can be ignored; the electrical connection between the drive control system 7 and the pole piece boundary detection mechanism 6 in step S22 has almost no delay and can be ignored; the response time of the encoder 31 in step S23 is less than 1ms and can be ignored; since the drive control system 7 has obtained accurate encoder position information in step S23, step S24 only sends the result to the pole piece detection device, so the network delay between the pole piece detection system 8 and the drive control system 7 in S24 does not affect the detection error of the pole piece boundary position.

[0109] In the improved solution of this embodiment, the detection error of the pole piece boundary position depends only on the response time of the pole piece boundary detection mechanism 6 and the encoder 31. The response time of the current pole piece boundary detection mechanism 6 and the encoder 31 is less than 1ms, and the detection accuracy of the pole piece boundary position is extremely high and is almost unaffected by the movement speed of the pole piece detection mechanism 5.

[0110] The pole piece detection instrument 100 provided by the utility model has at least the following advantages: 1. Online measurement and real-time update, which is more efficient, more flexible and has a wider range of applications than the existing technology; 2. Low cost, simple installation and strong ease of use; 3. The accuracy is usually maintained within 0.05mm, which can meet most pole piece detection and production needs and has a wide range of applications.

[0111] It can be understood that the above-mentioned technical features can be used in any combination without limitation.

[0112] The above embodiments only express the specific implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the patent scope of the utility model. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the utility model, the above technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the utility model. Therefore, all equivalent changes and modifications made to the scope of the claims of the utility model should belong to the scope covered by the claims of the utility model.

Claims

1. A pole piece detection instrument, characterized in that: The pole piece detection instrument comprises: Base (1); A bracket (4) is movably arranged on the base (1); A driving mechanism (2) is mounted on the base (1) and is used to drive the bracket (4) to move on the base (1); A position measuring device (3) for detecting position information of the driving mechanism (2); a drive control system (7), electrically connected to the drive mechanism (2) and the position measuring device (3), respectively, for controlling the operation of the drive mechanism (2) and receiving the position information; A pole piece detection mechanism (5), fixed on the bracket (4), and used for detecting pole piece information; A pole piece boundary detection mechanism (6), fixed on the pole piece detection mechanism (5), and used for detecting pole piece boundary position information; and A pole piece detection system (8) has the function of calculating the pole piece boundary position, the pole piece detection system (8) receives the position information, pole piece information and pole piece boundary position information, and outputs control information to the drive control system (7); or the pole piece detection system (8) receives the pole piece information, and the drive control system (7) has the function of calculating the pole piece boundary position.

2. The pole piece detection instrument according to claim 1, characterized in that: The pole piece detection system (8) is respectively connected to the pole piece detection mechanism (5), the pole piece boundary detection mechanism (6), and the drive control system (7).

3. The pole piece detection instrument according to claim 2, characterized in that: The pole piece detection system (8) has the function of calculating the pole piece boundary position. The pole piece detection system (8) receives the position information, pole piece information and pole piece boundary position information, and outputs control information to the drive control system (7). The pole piece detection system (8) is respectively connected to the pole piece detection mechanism (5), the pole piece boundary detection mechanism (6) and the drive control system (7) through a network.

4. The pole piece detection instrument according to claim 1, characterized in that: The pole piece detection system (8) receives the pole piece information, the drive control system (7) has the function of calculating the pole piece boundary position, the pole piece detection system (8) is respectively connected to the pole piece detection mechanism (5) and the drive control system (7) through a network, and the pole piece boundary detection mechanism (6) is electrically connected to the drive control system (7).

5. The pole piece detection instrument according to claim 1, characterized in that: The driving mechanism (2) comprises a driving motor (21), a screw (23), a screw nut and a guide rail (25). The drive motor (21) is electrically connected to the drive control system (7), the screw rod (23) is connected to the drive motor (21), the screw rod nut is threadedly connected to the screw rod (23) and the bracket (4), and the bracket (4) is limited to move on the guide rail (25). When the drive control system (7) controls the drive motor (21) to operate, the drive motor (21) drives the screw rod (23) to rotate so that the screw rod nut moves along the screw rod (23), thereby driving the bracket (4) to move along the guide rail (25).

6. The pole piece detection instrument according to claim 5, characterized in that: The position measuring device (3) comprises an encoder (31), and the encoder (31) is fixed on the drive motor (21).

7. The pole piece detection instrument according to claim 5, characterized in that: The support (4) comprises a support base (41) movably arranged on the guide rail (25) and a support body (42) fixed on the support base (41), and the pole piece detection mechanism (5) is fixed on the support body (42).

8. The pole piece detection instrument according to claim 1, characterized in that: The pole piece information includes pole piece thickness and pole piece thinning area data, and the position information includes the current running position, current running speed and current running direction of the driving mechanism (2).

9. The pole piece detection instrument according to claim 1, characterized in that: The pole piece detection mechanism (5) comprises a first pole piece detection device (51) and a second pole piece detection device (52), The first pole piece detection device (51) and the second pole piece detection device (52) are respectively fixed to the upper end and the lower end of the bracket (4), and detect the pole piece information from upper and lower directions respectively.

10. The pole piece detection instrument according to claim 9, characterized in that: The pole piece boundary detection mechanism (6) is fixed on the first pole piece detection device (51) or the second pole piece detection device (52).

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