Die lip opening control device
By precisely adjusting the die lip opening using a digital control device, the problem of relying on manual experience for adjusting the thickness of existing lithium battery separators has been solved, achieving high-precision and stable separator production, and improving product quality consistency and production efficiency.
Patent Information
- Application Number
- CN202520380055.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-06
- Publication Date
- 2026-02-13
- Estimated Expiration
- 2035-03-06
AI Technical Summary
Existing lithium battery separator thickness adjustment technology relies on manual experience, resulting in low adjustment accuracy and poor product quality consistency. Furthermore, traditional thermosensitive materials have limited adjustment range, making it difficult to meet production needs.
Using engineering and digital control methods, the screwing component is driven by the X, Y, and Z axis movement modules to tighten the fine-tuning bolts, thereby achieving precise adjustment of the mold lip opening. This is combined with real-time thickness detection data for automatic control.
It improves the precision of mold lip opening control, ensures the consistency and production stability of diaphragm products, reduces raw material waste, and improves production efficiency.
Smart Images
Figure CN223904502U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of lithium battery diaphragm preparation, and specifically relates to a die lip opening control device. BACKGROUND
[0002] The uniformity control of the thickness of the lithium battery diaphragm, which is a core parameter determining the performance and safety of the battery, is a key quality index in the production process. When the thickness of the diaphragm is unevenly distributed, not only will the charge and discharge efficiency and the cycle stability of the battery be significantly degraded, but also safety hazards such as local thermal runaway or internal short circuit may be caused. Therefore, precise thickness detection must be implemented before the diaphragm winding process, and dynamic adjustment of the die lip opening of the die head is implemented based on real-time detection data to ensure product homogenization.
[0003] There are mainly two implementation schemes for the current die lip opening adjustment technology: the traditional manual adjustment method adopts a mechanical fine adjustment bolt structure, and the operator records the thickness distribution by analyzing the real-time data of a thickness gauge or relying on the winding touch feeling, and physically rotates the bolt at a specific position using a professional tool to change the gap between the die lips to the preset parameters. Although this method can achieve thickness control of the diaphragm, the control effect completely depends on the experience accumulation and skill level of the operator, resulting in large dispersion of the adjustment precision, fluctuation of the product pass rate, and poor quality consistency. Another adjustment method uses a thermosensitive material to process a fine adjustment bolt, and adjusts the length of the bolt by electric heating to control the gap between the die lips. However, due to the physical properties of the material thermal expansion coefficient, the adjustment range is limited, and it is difficult to adapt to production needs. SUMMARY
[0004] In view of the above technical problems, the purpose of the present utility model is to provide a die lip opening control device, which uses an engineering and digital control method to replace manual control of the die lip opening of the die head, and has high control precision.
[0005] In order to achieve the above purpose, the die lip opening control device provided by the present utility model comprises:
[0006] for adjusting the gap of the extrusion slit of the die head, the die head has a fine adjustment bolt, characterized in that the control device comprises:
[0007] a screwing assembly, the screwing assembly comprises a sleeve and a motor for driving the sleeve to rotate, the sleeve has a cavity matched with the shape of the head of the fine adjustment bolt;
[0008] a driving mechanism, which is drivingly connected with the screwing assembly and is used for driving the screwing assembly to move along a predetermined trajectory.
[0009] In some embodiments, the screwing assembly comprises an X-axis moving module, a Y-axis moving module and a Z-axis moving module, the Z-axis moving module is arranged at the moving end of the Y-axis moving module, the Y-axis moving module is arranged at the moving end of the X-axis moving module, and the screwing assembly is arranged at the moving end of the Z-axis moving module.
[0010] In some embodiments, the X-axis moving module, the Y-axis moving module and the Z-axis moving module each comprise a ball screw nut pair structure for realizing movement in the X-axis, Y-axis and Z-axis directions.
[0011] In some embodiments, the Y-axis moving module is arranged on the screw nut seat of the X-axis moving module, and the Z-axis moving module is arranged on the screw nut seat of the Y-axis moving module.
[0012] In some embodiments, the X-axis moving module, the Y-axis moving module and the Z-axis moving module further comprise a linear guide rail and a guide rail slider, the linear guide rail extends in the axial direction of the ball screw, the guide rail slider is fixedly installed on the screw nut seat, and the guide rail slider and the linear guide rail are in sliding fit.
[0013] In some embodiments, the axial direction of the sleeve is parallel to the axial direction of the fine adjustment bolt.
[0014] Compared with the prior art, the utility model has the following beneficial effects:
[0015] The driving mechanism can drive the screwing assembly to move to the fine adjustment bolt, the screwing assembly can screw the fine adjustment bolt, and the die lip opening can reach the expected value. Since the engineering and digital control method is used to replace manual control of the die lip opening, the adjustment result of the die lip opening can be obtained in a short time, the control precision of the die lip is high, and stable and consistent diaphragm products can be stably produced. BRIEF DESCRIPTION OF DRAWINGS
[0016] The above characteristics, technical features, advantages and implementation modes of the utility model will be further described in the following preferred embodiments in a clear and understandable manner combined with the drawings.
[0017] Figure 1 is the structure schematic view of the die lip opening control device of the lithium battery diaphragm cast piece forming device.
[0018] Figure 2 is the structure schematic view of the die lip opening control device of the lithium battery diaphragm cast piece forming device.
[0019] Figure 3 is Figure 2 the structure schematic view of the moving module.
[0020] BRIEF DESCRIPTION OF DRAWINGS:
[0021] Die 1; fine adjustment bolt 11; chill roll 2; first thickness gauge 3; second thickness gauge 4; controller 5; driving mechanism 6; rack 61; X-axis moving module 62; Y-axis moving module 63; Z-axis moving module 64; support seat 65; screwing assembly 7; sleeve 71; motor 72; stepping motor 81; screw nut seat 82; linear guide rail 83; guide rail slider 84. DETAILED DESCRIPTION
[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, specific embodiments of the present application will be described below with reference to the drawings. Obviously, the drawings described below are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained from these drawings without creative labor, and other embodiments can also be obtained.
[0023] Please refer to the specification Figures 1 to 3 The lithium battery diaphragm cast sheet forming system provided by the embodiment of the present application comprises a die 1, a chill roll 2, a first thickness gauge 3, a second thickness gauge 4 and a die lip opening control device. The die 1 is used for extruding the melt flowing out from the extruder into a sheet, and the die 1 has a cavity. The cavity bottom is provided with a fixed die lip and a movable die lip which are opposite to each other. The fixed die lip and the movable die lip cooperate to form an extrusion slit. The high-temperature melt in the cavity of the die 1 can flow out through the extrusion slit, and the sheet formed by the melt flows from the side of the die 1 to the side of the chill roll 2. The chill roll 2 is used for cooling the sheet, so that the temperature of the high-temperature sheet is rapidly reduced to below the glass transition temperature. The sheet changes from a viscous flow state to an amorphous solid cast sheet, avoiding the influence of crystallization on subsequent stretching. After the cast sheet is subjected to stretching, extraction, drying and other processes, a diaphragm finished product is finally formed.
[0024] In the embodiment, the movable die lip is provided with a plurality of fine adjustment bolts 11, which are distributed along the length direction of the movable die lip, for adjusting the gap of the extrusion slit. It should be noted that the transverse direction in the embodiment refers to the length direction of the extrusion slit. In the embodiment, the sheet, the cast sheet and the diaphragm can be divided into a plurality of transverse intervals in the transverse direction, and the transverse intervals have a corresponding relationship with the fine adjustment bolts 11. By rotating the fine adjustment bolts 11, the gap of the extrusion slit at the corresponding position can be increased or decreased, so as to adjust the thickness of the sheet, the cast sheet and the final diaphragm. The first thickness gauge 3 and the second thickness gauge 4 can move back and forth in the transverse direction. The first thickness gauge 3 is used to measure the thickness of each transverse interval of the cast sheet, and the second thickness gauge 4 is used to measure the thickness of each transverse interval of the diaphragm. The structure for driving the first thickness gauge 3 and the second thickness gauge 4 is not limited in the embodiment, for example, the first thickness gauge 3 and the second thickness gauge 4 are driven to move linearly by a linear guide rail or the like. The die lip opening control device in the embodiment controls the fine adjustment bolts 11 based on the data collected by the first thickness gauge 3 and the second thickness gauge 4, so as to adjust the thickness of the sheet in the transverse direction.
[0025] Before starting the diaphragm production process, a target thickness reference system needs to be established. A diaphragm reference sample meeting the quality standard is obtained through trial production, and the target thickness range of the cast sheet is determined based on the thickness distribution data of the cast sheet recorded by the first thickness gauge 3. In the embodiment, the system synchronously collects the thickness data of the first thickness gauge 3 (cast sheet detection) and the second thickness gauge 4 (diaphragm finished product detection) according to a preset sampling period, and establishes a thickness data change curve based thereon. The real-time data is compared with the target thickness. When the measured thickness of any detection point deviates from the target interval (the maximum threshold value is set to +8%, and the minimum threshold value is set to -5%), the system automatically activates the sound and light alarm and / or prompts through the human-computer interaction interface. The thickness data change curve is a curve with production time as the horizontal axis, which is drawn according to the thickness data collected by the first thickness gauge 3 and the second thickness gauge 4. The target thickness range includes the maximum threshold value and the minimum threshold value. For example, when any thickness data on the thickness data change curve of the diaphragm exceeds the maximum threshold value, a sound alarm and / or a prompt through the human-computer interaction interface can be given. For example, the thickness data change curve of the diaphragm is maintained near the minimum threshold value, which indicates that the production process is normal. However, the utility model is not limited thereto. In some embodiments of the utility model, the condition that the thickness data exceeds the maximum threshold value or is less than the minimum threshold value can be set as the alarm / prompt condition.
[0026] In the online production control stage, the thickness data of each lateral section of the cast sheet is plotted as a function of production time based on the thickness data collected by the first thickness gauge 3, and the gap of the extrusion slit corresponding to each lateral section of the cast sheet is re-set based on the trend of the thickness data of each lateral section of the cast sheet. For example, when the thickness data of a certain lateral section of the cast sheet exceeds a minimum threshold value and the slope of the curve exceeds a certain threshold value within a certain time period, it indicates that the thickness data changes dramatically within the time period, and the opening of the die lip can be automatically adjusted to ensure that the thickness of any lateral section of the cast sheet is stable within the corresponding target range.
[0027] After the sheet is formed into a cast sheet, it still needs to go through the steps of stretching, extraction, drying, etc., and the factors affecting the final thickness of the separator membrane include the stretching ratio of each lateral section of the cast sheet, etc., so even if the thickness of the cast sheet is stable within the pre-set target range, when the temperature of a certain lateral section of the cast sheet changes or the stretching ratio changes, it will still affect the final thickness of the separator membrane. Therefore, in this embodiment, the system also plots the thickness data of each lateral section of the separator membrane as a function of production time based on the thickness data collected by the second thickness gauge 4, and re-sets the target thickness of the cast sheet based on the trend of the thickness data curve, and adjusts the gap of the extrusion slit corresponding to each lateral section of the cast sheet based on the re-set target thickness of the cast sheet. For example, when the thickness data of a certain lateral section of the separator membrane exceeds a minimum threshold value and the slope of the curve exceeds a certain threshold value within a certain time period, it indicates that the thickness data of the separator membrane changes dramatically within the time period, the stretching ratio of the cast sheet has changed, and the original set target thickness range of the cast sheet cannot meet the actual needs. The target thickness of the cast sheet can be corrected based on the relationship between the actual thickness of the cast sheet and the actual thickness of the separator membrane within the time period, and the opening of the die lip is adjusted based on the corrected target thickness of the cast sheet to ensure that the thickness of each lateral section of the cast sheet is stable within the corrected target range of the cast sheet.
[0028] It can be understood that the thickness of the diaphragm is determined by the thickness of the cast sheet and the subsequent stretching process. The greater the stretching ratio of the cast sheet, the smaller the thickness of the finished diaphragm. In the process of biaxial stretching, the cast sheet is stretched in the longitudinal direction (MD) and the transverse direction (TD), and the thickness is significantly reduced. The thickness conversion relationship between the cast sheet and the diaphragm is T_final = T_cast / (MD_ratio x TD_ratio), wherein T_final is the thickness of the diaphragm, T_cast is the thickness of the cast sheet, and MD_ratio and TD_ratio are the stretching ratios in the longitudinal direction and the transverse direction, respectively. For example, if the thickness of the cast sheet is 100 μm, the diaphragm is stretched by 3 times in the longitudinal direction and 5 times in the transverse direction, and the thickness of the finished diaphragm is about 100 / (3x5) = 6.67 μm. Therefore, based on the actual thickness of the diaphragm and the cast sheet, the stretching ratio of any transverse interval of the cast sheet can be determined, and the target thickness of the cast sheet can be corrected according to the stretching ratio, so as to ensure that the thickness of the finished diaphragm is always maintained within the predetermined range.
[0029] In this embodiment, a first thickness gauge 3 is arranged at the upstream end of the mechanical flow direction of the production line, and a second thickness gauge 4 is arranged at the downstream end. There is a predetermined distance between the two thickness gauges. Due to the time lag effect in the process of transporting the cast sheet, in order to match the data collected by the first thickness gauge 3 and the second thickness gauge 4, the thickness data collected by the first thickness gauge 3 and the second thickness gauge 4 need to be time-sequenced. As time-sequencing, the time delay (time lag) can be appropriately corrected according to the speed of the mechanical flow. Specifically, the distance between the first thickness gauge 3 and the second thickness gauge 4 is determined in advance, the time delay for obtaining the thickness data of the cast sheet and the diaphragm is corrected according to the speed of the mechanical flow, and the data is stored. In this way, the thickness data of the first thickness gauge 3 and the second thickness gauge 4 can correspond to each other respectively, and the time delay is corrected.
[0030] In this embodiment, the target thickness of the cast sheet can be corrected in real time according to the data of the first thickness gauge 3 and the second thickness gauge 4, and the opening of the die lip can be automatically controlled according to the target thickness of the cast sheet, so as to realize the uniformization of the diaphragm thickness. In addition, the adjustment of the die lip opening is based on the target thickness of the cast sheet. Since the distance between the die 1 and the first thickness gauge 3 is short, the adjustment result of the die lip opening can be obtained in a short time, which helps to reduce the waste of raw materials.
[0031] In this embodiment, the die lip opening control device comprises a controller 5, a driving mechanism 6 and a screwing assembly 7. The screwing assembly 7 is connected to the driving mechanism 6, and the controller 5 is signal connected to the driving mechanism 6 and the screwing assembly 7. The controller 5 is used to control the opening and closing of the driving mechanism 6 and the screwing assembly 7.
[0032] Specifically, please refer to the accompanying drawings Figure 1The screwing assembly 7 is connected to the driving mechanism 6, and the driving mechanism 6 is controlled by the controller 5 to drive the screwing assembly 7 to move to the fine adjustment screw 11, and the fine adjustment screw 11 is screwed by the screwing assembly 7, so that the die lip opening reaches the expected value.
[0033] The driving mechanism 6 comprises an X-axis moving module 62, a Y-axis moving module 63 and a Z-axis moving module 64. For the convenience of description, a right-hand XYZ orthogonal coordinate system with the gravity direction as the reference is set, the length direction of the extrusion gap is set as the X-axis direction, the horizontal direction perpendicular to the X-axis direction is set as the Y-axis direction, and the direction perpendicular to the horizontal direction is set as the Z-axis direction.
[0034] The X-axis moving module 62 is used to realize the linear motion of the X-axis. The X-axis moving module 62 can be installed on the ground, for example, in the form of existing rails and rail wheels; the X-axis moving module 62 can also be suspended above the ground, for example, suspended on the ceiling in the room, using the existing row of hoist structure, therefore, the X-axis moving module 62 can be arranged according to the needs or the structure of the site, at the same time, the X-axis moving module 62 can use existing equipment, for example, a crane, a rail and rail wheel combination structure, a gear and rack, a gear and chain, a pulley system, a combination of a steel cable winch and a motor on both ends of a support base 65 to pull along the X-axis to realize the movement. The support base 65 is connected to the X-axis moving module 62, and the X-axis moving module 62 drives the support base 65 to move in the X-axis direction; the support base 65 can be used as a mounting base for parts, and the structure can be set as needed.
[0035] The Y-axis moving module 63 is used to realize the movement in the Y-axis direction. The Y-axis moving module 63 is movably connected to the support base 65, so that the support base 65 drives the Y-axis moving module 63 to move in the X-axis direction, realizing the position change of the Y-axis moving module 63 in the X-axis direction. The Y-axis moving module 63 can also use existing equipment such as ball screw nut pair, gear and rack, gear and chain, air cylinder, hydraulic cylinder and pulley system.
[0036] The Z-axis moving module 64 is used to realize the movement in the Z-axis direction. The Z-axis moving module 64 is connected to the Y-axis moving module 63, so that the Y-axis moving module 63 drives the Z-axis moving module 64 to move, realizing the position change of the Z-axis moving module 64 in the Y-axis direction.
[0037] As an example, the X-axis movement module 62 is connected to the rack 61, the Y-axis movement module 63 is arranged at the moving end of the X-axis movement module 62, the Z-axis movement module 64 is arranged at the moving end of the Y-axis movement module 63, and the screwing assembly 7 is arranged at the moving end of the Z-axis movement module 64, that is, the X-axis movement module 62, the Y-axis movement module 63 and the Z-axis movement module 64 are connected to the screwing assembly 7 in a series mode, so that the screwing assembly 7 can be used in cooperation with the X-axis movement module 62, the Y-axis movement module 63 and the Z-axis movement module 64 to realize movement in the X-axis, Y-axis and Z-axis directions.
[0038] In the embodiment, the X-axis movement module 62, the Y-axis movement module 63 and the Z-axis movement module 64 can adopt the same structural design and each include a stepping motor 81, a shaft coupling, a ball screw, a screw nut seat 82, a linear guide rail 83 and a guide rail slider 84. The output end of the stepping motor 81 is rigidly connected to the ball screw in a direct drive mode through the shaft coupling, the ball screw penetrates through the screw nut seat 82 and is threadedly connected to the screw nut seat 82, so that the screw nut seat 82 can precisely reciprocate along the axis of the ball screw when the stepping motor 81 is driven. The linear guide rail 83 extends along the axis of the ball screw, the guide rail slider 84 is fixedly installed on the screw nut seat 82, and the guide rail slider 84 and the linear guide rail 83 are in sliding fit, and the two constitute a double-direction limiting mechanism to ensure that the compound movement track of the screw nut seat 82 and the guide rail slider 84 is strictly controlled and the movement stroke is limited in the mechanical interval formed by the bearing seats on both sides of the ball screw. Thus, the movement modules in the embodiment are assembled in a hierarchical superposition mode, the Y-axis movement module 63 is integrally installed on the screw nut seat of the X-axis movement module 62, and the Z-axis movement module 64 is further mounted on the top of the screw nut seat of the Y-axis movement module 63, so as to realize precise displacement control in three-dimensional space through three-axis linkage.
[0039] The screwing assembly 7 is connected to the Z-axis movement module 64, so that the screwing assembly 7 is moved in the Z-axis direction by the Z-axis movement module 64 to realize the position change of the screwing assembly 7 in the Z-axis direction. Finally, the position of the screwing assembly 7 is adjusted through the position changes of the X-axis movement module 62, the Y-axis movement module and the Z-axis movement module 64, so as to realize the position adjustment. Since the position of the screwing assembly 7 is adjusted through automatic control, the position of the screwing assembly 7 can be precisely adjusted, and the accuracy of the alignment of the screwing assembly 7 with the fine adjustment bolt 11 when the fine adjustment bolt 11 is rotated by the screwing assembly 7 is realized.
[0040] The screwing assembly 7 comprises a sleeve 71 for clamping the fine adjustment screw 11, and a motor 72 for rotating the sleeve 71 after the fine adjustment screw 11 has been clamped by the sleeve 71. The sleeve 71 has a cavity matching the shape of the head of the fine adjustment screw 11, and the axial direction of the sleeve 71 is preferably parallel to the axial direction of the fine adjustment screw 11. In addition, the screwing assembly 7 further comprises a position detection device for detecting the position of the screwing assembly 7, and the movement track of the screwing assembly 7 can be preset according to the installation position of different fine adjustment screws 11. In use, after the fine adjustment screw 11 to be adjusted is determined, the driving mechanism 6 is controlled by the controller 5 to drive the screwing assembly 7 to move, and the position detection device checks whether the screwing assembly 7 has moved to the position. When the screwing assembly 7 is aligned with the adjustment screw, a feedback signal is fed back to the controller 5, and after the controller 5 determines that the screwing assembly 7 has moved to the position, the screwing assembly 7 can perform the next action. In the embodiment, the position detection device can adopt a position sensor, a visual detection device, etc., which is not limited herein.
[0041] It should be noted that the above embodiments can be freely combined as needed. The above is only a preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which improvements and refinements should also be considered within the protection scope of the present application.
Claims
1. A lip opening control device for adjusting the gap of an extrusion slot of a die, said die having a fine adjustment screw, characterized in that, The control device comprises: a screwing assembly comprising a sleeve and a motor for driving the sleeve to rotate, the sleeve having a cavity matched with the head of the fine adjustment bolt; a driving mechanism drivingly connected with the screwing assembly for driving the screwing assembly to move along a predetermined trajectory.
2. The control device for the die lip opening degree according to claim 1, wherein: the screwing assembly comprises an X-axis moving module, a Y-axis moving module and a Z-axis moving module, the Z-axis moving module is arranged at the moving end of the Y-axis moving module, the Y-axis moving module is arranged at the moving end of the X-axis moving module, and the screwing assembly is arranged at the moving end of the Z-axis moving module.
3. The control device for the die lip opening degree according to claim 2, wherein: the X-axis moving module, the Y-axis moving module and the Z-axis moving module each comprise a ball screw nut pair structure for realizing the movement in the X-axis, Y-axis and Z-axis directions.
4. The control device for the die lip opening degree according to claim 3, wherein: the Y-axis moving module is arranged on the screw nut seat of the X-axis moving module, and the Z-axis moving module is arranged on the screw nut seat of the Y-axis moving module.
5. The control device for the die lip opening degree according to claim 4, wherein: the X-axis moving module, the Y-axis moving module and the Z-axis moving module further comprise a linear guide rail and a guide rail slider, the linear guide rail extends along the axial direction of the ball screw, the guide rail slider is fixedly installed on the screw nut seat, and the guide rail slider and the linear guide rail are in sliding fit.
6. The control device for the die lip opening degree according to claim 1, wherein: the axial direction of the sleeve is parallel to the axial direction of the fine adjustment bolt.