Single-shaft continuous web paddle stirring mechanism and pre-spraying device using same

Abstract

The application provides a single-shaft continuous web paddle stirring mechanism and a pre-spraying device using the same. The stirring mechanism is a horizontal stirring barrel matched with a single-shaft continuous web paddle. The supporting rod of the single-shaft continuous web paddle is plate-shaped or sheet-shaped, and the included angle between the supporting rod and the normal plane B of the stirring shaft is β1. When rotating, the supporting rod cuts the powder. The included angle between the web-shaped paddle of the single-shaft continuous web paddle and the tangent plane A of the stirring shaft is α1. The outer edge of the curved paddle is raised and adheres to the barrel wall. The included angle between the web-shaped paddle of the single-shaft continuous web paddle and the normal plane B of the stirring shaft is β2. When rotating, the n web paddles push the powder to be continuously stirred in an uneven stress along the X direction from the feeding port. Under the continuous pushing action of the web-shaped paddle, the powder gradually moves laterally and slowly to the discharging port. Through a series of structural improvements of the stirring mechanism, the application finally realizes the accuracy of 0.1g-0.01g of the discharging precision, and accurately controls the inert dust spraying amount of the pre-spraying device to 200g / h±20% of the deviation amount of the high requirement.

Description

Technical Field

[0001] This invention relates to explosion-proof inerting treatment of dust removal devices, and more particularly to a single-shaft continuous paddle stirring mechanism and a pre-coating device using the same. Background Technology

[0002] Currently, the lithium battery industry is developing rapidly, but lithium battery production workshops have extremely stringent environmental requirements, making dust collectors an essential device. Furthermore, the raw materials for lithium batteries are highly reactive, such as carbon powder, posing a high risk of dust explosion. These environmental and safety issues in the production process have constrained the development of the power battery industry. However, using a pre-coating device to spray inert dust into the dust collector can significantly reduce the risk of explosion within the dust collector. Therefore, pre-coating devices play an irreplaceable and crucial role in the production and manufacturing of lithium batteries.

[0003] The pre-coating device, also known in the industry as an inerting device, mainly consists of a mixing mechanism, a feeding and conveying mechanism, and a negative pressure receiving mechanism. After the inert dust is mixed in the mixing mechanism, it is conveyed by the feeding and conveying mechanism to the negative pressure receiving mechanism and then sucked into the dust collector. The inerting powder disperses and adheres to the filter components (such as filter bags or filter cartridges) in the dust collector, forming a protective powder film on the filter bags or filter cartridges. This film can fully absorb or extinguish oily, sticky particles, droplets, and even sparks on the surface of the filter material. It can also significantly reduce the density of explosive dust, thereby protecting the filter components and preventing the risk of dust explosion in the dust collector.

[0004] The pre-coating devices currently used in the industry have the following problems: 1. Front-line power battery production workshops have strict requirements for coating accuracy and quality. For example, existing customers require the coating amount to be precisely controlled to a deviation of 200g / h±20%, but the current pre-coating devices cannot meet this powder addition accuracy requirement; 2. The current pre-coating devices usually use a vertical mixing drum with the discharge port located at the bottom. In order to ensure stable feeding, only a small mixing paddle is set at the discharge port. The mixing span and mixing fullness are insufficient, and the inert powder has high viscosity. Therefore, the device is prone to jamming, and the inner page of the mixing drum often has problems such as powder adhesion, caking, and severe bridging.

[0005] To address the aforementioned issues, our company has made key structural improvements and designs to the mixing mechanism of the pre-coating device. This has significantly improved the mixing span and mixing quality, resolving problems such as powder caking, bridging, and adhesion. Furthermore, it has enabled the mixing mechanism to work in harmony with the feeding and conveying devices and the receiving device, achieving closed-loop stability control in the event of weight loss and reaching an accuracy of 200g / h ± 20%. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of insufficiently stable and uniform stirring and inaccurate material discharge in existing pre-coating devices, and to propose a single-shaft continuous paddle stirring mechanism and a pre-coating device using it.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A single-shaft continuous paddle mixing mechanism includes a horizontal mixing drum, a mixing shaft, and paddles; the bottom sidewall of the horizontal mixing drum is arc-shaped and its axis extends along the X direction; a feeding port is provided at the first end of the horizontal mixing drum along the X direction and a discharge port is provided at the bottom end along the X direction; the mixing shaft is installed inside the horizontal mixing drum along the X direction; n paddles are installed on the mixing shaft, n≥2; each paddle includes a support rod installed on the mixing shaft and a web-shaped blade installed at the tail end of the support rod.

[0009] The cross-section A and the normal surface B of the horizontal mixing drum are perpendicular to each other. The support rod is a sheet-like or thin plate-like structure. The angle between the support rod and the normal surface B is β1, 0≤β1≤90°. When the mixing shaft is driven to rotate, the support rod rotates accordingly and cuts the powder.

[0010] The angle between the webbed blade and the cut surface A is α2, 0 < α2 < 90°. The webbed blade is a webbed plate or sheet, and the outer edge of the webbed blade is shaped like a polynomial spline difference curve that fits the inner wall of the horizontal stirring cylinder. When the stirring shaft is driven to rotate, the outer edge of the webbed blade scrapes against the bottom arc plate of the horizontal stirring cylinder at equal intervals along the spline curve.

[0011] The angle between the webbed blades and the normal plane B along the X direction is β2, where 0 < β2 < 90°. When the stirring shaft is driven to rotate, the webbed blades push the powder in the horizontal stirring drum to move along the X direction. The n webbed blades push the powder from the feed port along the X direction to continuously stir it under uneven force. Under the continuous pushing action of the webbed blades, the powder gradually moves laterally and slowly to the discharge port.

[0012] Preferably, the single-shaft continuous paddle stirring mechanism further includes two support-type weighing sensors, which are symmetrically installed on both sides of the horizontal stirring drum and suspend the horizontal stirring drum inside the top of the pre-coating device housing. The support-type weighing sensors detect the weight of the horizontal stirring drum in real time and control the rotation speed of the stirring shaft. When the weight detected by the two support-type weighing sensors is normal and the weight difference does not exceed a preset value, the paddle maintains a uniform low speed v1 rotation. When the weight detected by the two support-type weighing sensors is abnormal or the weight difference continues to exceed the preset value and cannot be corrected, the stirring speed of the paddle is increased to v2.

[0013] Preferably, the two sides of the horizontal stirring drum are vertically suspended on the support-type weighing sensor, and the difference between the height of the support-type weighing sensor and the height of the stirring shaft is less than 100mm.

[0014] Preferably, the angle β1 between the support rod and the normal plane B is 0°.

[0015] Preferably, the included angle α2 between the webbed blades and the cut surface A is in the range of 10°≤α2≤20°.

[0016] Preferably, the angle β2 between the webbed blades and the normal plane B along the X direction is in the range of 30°≤β2≤50°.

[0017] Preferably, the paddles are evenly arranged on the stirring shaft, the distance between two adjacent paddles along the X direction is equal, and the included angle between the projections of two adjacent paddles on the normal plane B is 360° / n, where n≥2.

[0018] A pre-coating device includes a housing and a single-axis continuous fin paddle agitator as described in any of the preceding claims; the single-axis continuous fin paddle agitator is mounted inside the housing and located on top of it.

[0019] Preferably, it further includes a double-helix feeding mechanism installed inside the housing, the double-helix feeding mechanism being installed below the single-axis continuous paddle mixing mechanism and receiving and transporting the powder inside the single-axis continuous paddle mixing mechanism.

[0020] Preferably, it also includes a feeding mechanism installed inside the housing, the feeding mechanism being located at the tail end of the double-helix feeding mechanism, the feeding mechanism being used to draw powder under negative pressure and deliver it to the dust collector.

[0021] Compared with the vertical or ordinary horizontal mixing drums commonly used in current inerting dust pre-coating devices, the present invention uses a horizontal mixing drum and is equipped with a single-shaft continuous webbed paddle, which enables more thorough, uniform and fine mixing; it can prevent powder from caking, bridging and sticking to the drum wall, so that the weight distribution of powder in the drum is always uniform; it can effectively ensure the stability of the mixing drum, especially the suspended mixing drum, during the mixing process, and prevent shaking, thereby ensuring smooth and uniform feeding and more accurate weight detection of the mixing drum, improving the feeding accuracy of the mixing mechanism.

[0022] Through a series of structural improvements to the stirring mechanism, this invention can ultimately achieve a feeding accuracy of 0.1g-0.01g. The stirring mechanism, feeding and conveying mechanism, and receiving and feeding mechanism work together to ensure that the amount of inert dust sprayed by the pre-spraying device is precisely controlled to a deviation of 200g / h±20%. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the internal structure of the mixing mechanism and the screw feeder conveyor mechanism that are to be connected to it.

[0024] Figure 2 This is a three-dimensional structural diagram of the stirring shaft and the paddle.

[0025] Figure 3 This is a front view of the stirring shaft and the paddle.

[0026] Figure 4 Right view of the stirring shaft and the paddle web;

[0027] Figure 5 A schematic diagram of a structure where the included angle β2 between the support rod of the paddle and the normal plane B is not 0;

[0028] Figure 6 This is a schematic diagram of the main structure of the pre-coating device;

[0029] Figure 7 Right view of the internal structure of the pre-coating device;

[0030] Figure 8 This is a schematic diagram of the overall external structure of the pre-coating device. Detailed Implementation

[0031] To provide a further understanding of the purpose, structure, features, and functions of the present invention, detailed descriptions are provided below with reference to specific embodiments.

[0032] The ultimate goal of this invention is to improve the mixing mechanism in the pre-coating device, achieving a feeding accuracy of 0.1g-0.01g and precisely controlling the inert dust spraying amount to a deviation of 200g / h ± 20% by refining the mixing mechanism. To this end, this invention improves the structure and construction of the mixing drum and mixing paddle, significantly enhancing the uniformity, stability, and precision of the mixing, thus achieving the aforementioned accuracy requirements.

[0033] The pre-coating device includes an outer shell, inside which are a stirring mechanism 200, a feeding and conveying mechanism, and a receiving and feeding mechanism 400.

[0034] like Figures 1-8 As shown, this invention protects a single-shaft continuous webbed paddle stirring mechanism, such as... Figure 1 and Figure 2As shown, it includes a horizontal mixing drum 1, a mixing shaft 2, and webbed paddles 3; the bottom sidewall of the horizontal mixing drum 1 is arc-shaped and its axis extends along the X direction. The front end of the horizontal mixing drum 1 along the X direction is provided with a feeding port and the rear end of the bottom along the X direction is provided with a discharge port. The mixing shaft 2 is installed inside the horizontal mixing drum 1 along the X direction. n webbed paddles 3 are installed on the mixing shaft 2, where n≥2. The webbed paddles 3 include a support rod 31 installed on the mixing shaft 2 and webbed blades 32 installed at the rear end of the support rod 31.

[0035] like Figure 1 , Figure 4 and Figure 5 As shown, the cross-section A and the normal surface B of the horizontal mixing drum 1 are perpendicular to each other. The support rod 31 is a sheet-like or thin plate-like structure. The angle between the support rod 31 and the normal surface B is β1, where 0 ≤ β1 < 90°. When the mixing shaft 2 is driven to rotate, the support rod 31 rotates accordingly and cuts the powder.

[0036] like Figure 1 and Figure 3 As shown, the angle between the webbed blade 32 and the cut surface A is α2, 0 < α2 < 90°. The webbed blade 32 is a webbed plate or sheet, and the outer edge 33 of the webbed blade 32 is shaped like a polynomial spline difference curve that fits the inner wall of the horizontal stirring tank 1. When the stirring shaft 2 is driven to rotate, the outer edge of the webbed blade 32 scrapes the bottom arc plate of the horizontal stirring tank 1 at equal intervals along the spline curve.

[0037] like Figure 1 and Figure 4 As shown, the angle between the webbed blades 32 and the normal plane B along the X direction is β2, 0 < β2 < 90°. When the stirring shaft 2 is driven to rotate, the webbed blades 32 push the powder in the horizontal stirring drum 1 to move along the X direction. The n webbed blades 3 push the powder from the feed port along the X direction to continuously stir it under uneven force. Under the continuous pushing action of the webbed blades 32, the powder gradually moves laterally and slowly to the discharge port.

[0038] The stirring mechanism 200 of this invention is a horizontal stirring drum 1, which differs from the vertical stirring drum commonly used in the pre-coating device for inert powder in dust collectors. The discharge port of a vertical stirring drum is located at the bottom. Due to gravity, the inert powder accumulates at the outlet, and the powder easily bridges or clumps at the bottom. Furthermore, the discharge rate from the lower outlet of the vertical stirring drum varies with the weight inside the drum, resulting in excessively large and unstable fluctuations in the discharge rate accuracy as the powder content decreases, leading to very low precision. The horizontal stirring drum 1 used in this application effectively avoids these problems.

[0039] First, the horizontal mixing drum 1 of this application has a feeding port at the first end along the X direction and a discharge port at the bottom end along the X direction. The feeding port and the discharge port are respectively located on both sides of the horizontal mixing drum 1. Therefore, the inert powder moves laterally in the horizontal mixing drum 1 under the stirring of the paddle 3 and is pushed to the discharge port for discharge. The discharge amount is not affected by the gravity of the powder, but is determined by the stirring and pushing of the paddle. This effectively avoids the inert powder from caking, bridging, etc., and avoids the accumulation and blockage of powder at the discharge port.

[0040] Secondly, since the powder distribution inside the horizontal mixing drum 1 will not accumulate at the discharge port due to gravity, and the mixing shaft 2 also stirs horizontally, the mixing shaft 2 can run through the entire horizontal mixing drum 1 along the X direction, unlike the vertical mixing drum where the powder distribution is uneven due to gravity, and generally only a small mixing paddle is set at the discharge port. Compared with vertical mixing, the bottom space span of the horizontal mixing is greatly increased, which can use a large single-shaft mixing paddle to fully, evenly and comprehensively stir the inert powder in the mixing drum, so that the powder is finer and more uniform overall, and further makes the control of the feeding amount more precise and accurate. The accuracy of the inert dust spraying amount of the spraying device is higher, and the spraying effect is better.

[0041] For some pre-coating devices that require high precision in spraying volume, sensors are used to monitor the weight of the mixing drum in real time and provide feedback control in order to achieve more accurate material feeding monitoring. However, in this case, the stability of the mixing drum will greatly affect the accuracy of the sensor detection. If the stirring resistance inside the mixing drum is too high or the weight inside the mixing drum is uneven, the weight value detected by the sensor will have a large deviation, resulting in a significant deviation in the material feeding volume, which greatly affects the accuracy of the output volume and thus affects the spraying effect. To solve the above problems, this application adopts a single-shaft continuous paddle 3 in conjunction with a horizontal mixing drum 1.

[0042] First, the support rod 31 of the single-shaft continuous paddle 3 is a sheet-like or thin-plate structure, with an angle β1 between it and the normal plane B, where 0 ≤ β1 < 90°. That is, when the stirring shaft 2 rotates, the support rod 31 rotates with the stirring shaft 2, and its angle with the rotation direction is either completely parallel or less than 90°. During rotation, it can cut the powder material, reduce resistance, and prevent vibration or shaking of the mixing drum during mixing. This ensures the mixing drum remains stable even when suspended, resulting in more uniform material feeding. Furthermore, for the pre-spraying device that uses sensors to detect the weight of the mixing drum, the detection is more accurate, leading to higher precision in controlling the material feeding amount. In a preferred embodiment, the angle β1 between the support rod 31 and the normal plane B is 0°. At this point, the support rod 31 is completely parallel to the rotation direction, resulting in minimal resistance during rotation, greater cutting force, and the best stability of the horizontal mixing drum 1.

[0043] Secondly, the blades of the single-shaft continuous webbed impeller 3 are designed with a webbed structure to enhance the contact area with the powder and improve the mixing effect. The included angle α2 between the webbed blade 32 and the sectional surface A causes the outer edge of the webbed blade 32 to curl upwards, which has at least the following beneficial effects: 1. The curled outer edge can scrape the bottom arc plate of the horizontal mixing drum 1 at equal intervals along the spline curve, which can clean the drum wall during rotation, effectively preventing inert powder from adhering and caking on the drum wall, thus avoiding uneven weight distribution in different parts of the horizontal mixing drum 1, improving the weight detection accuracy and precision of the sensor when detecting the mixing drum, thereby improving the accuracy of the feeding amount. 2. The presence of the included angle α2 allows the webbed blade 32 to push the powder inwards during mixing, so that the powder on the outside is continuously collected inwards during mixing, preventing the powder from accumulating and adhering to the drum wall. In this application, the bottom sidewall of the horizontal mixing drum 1 is arc-shaped, and its longitudinal cross-section can be U-shaped or circular, etc., to facilitate the webbed blades 32 to fully scrape and clean the drum wall during rotation. The U-shaped cross-section of the horizontal mixing drum 1, with its vertical sides, makes installation and fixation easier, further ensuring the stability of the horizontal mixing drum 1, and facilitating material feeding, resulting in greater space utilization. Because the size, shape, and curvature of the mixing drum can be customized according to actual needs, the outer edge 33 of the webbed blades 32, with its raised side, is shaped like a polynomial spline difference curve conforming to the inner wall of the horizontal mixing drum 1, thus achieving better mixing and cleaning effects. In a preferred embodiment, the angle α2 between the webbed blades 32 and the sectional plane A is in the range of 10°≤α2≤20°, within which the above-mentioned effects are optimal.

[0044] Furthermore, the presence of an angle β2 between the webbed blades 32 of the single-shaft continuous webbed paddle 3 and the normal plane B along the X direction allows the webbed blades 32 to laterally push the inert powder during rotation and stirring. The n webbed paddles 3 distributed on the stirring shaft 2 continuously push the inert powder laterally during rotation. The webbed blades 32's web-like shape provides a large contact area and stable pushing during lateral pushing. The powder is fed into the stirring drum from the inlet and continuously pushed laterally by the n webbed paddles 3 to the outlet, preventing the material from being agitated and scattered within the drum. The material falls evenly and orderly at the outlet under the stable pushing of the webbed paddles 3, thereby improving the feeding accuracy of the stirring mechanism 200. In a preferred embodiment, the angle β2 between the webbed blades 32 and the normal plane B along the X direction is in the range of 30°≤β2≤50°. Within this range, the above effect is optimal.

[0045] In summary, the horizontal mixing drum 1 and the single-shaft mixing paddle 3 of this invention work together to change the mixing method from the traditional vertical mixing to horizontal mixing. The structure of the single-shaft mixing paddle 3 ensures that even in horizontal mixing, the powder in the mixing drum can still be moved laterally in an orderly and continuous manner from the feeding port to the discharge port. The discharge volume at the discharge port is effectively and accurately controlled by the propulsion of the paddle 3, resulting in uniform, continuous, and stable discharge. The drum wall of the horizontal mixing drum 1 can remain clean throughout the mixing process, preventing powder from adhering and caking on the drum wall or accumulating in certain areas due to insufficient mixing, thus avoiding uneven weight distribution within the drum. The low resistance during mixing prevents vibration or shaking of the mixing drum, resulting in continuous, stable, and highly accurate material feeding. If a sensor is used for weighing detection, the accuracy of the measurement results will be even higher, and the control of the feeding volume will be more precise, achieving an accuracy of 0.1g-0.01g. The inert dust spraying volume of the pre-spraying device can be precisely controlled to a deviation of 200g / h ± 20%.

[0046] In a preferred embodiment, the single-shaft continuous paddle 3 stirring mechanism 200 further includes two support-type weighing sensors 4. The two support-type weighing sensors 4 are symmetrically installed on both sides of the horizontal stirring drum 1, suspending the horizontal stirring drum 1 inside the top of the housing 100 of the pre-spraying device. The difference between the weight detected each time and the weight detected last time is the discharge amount of the stirring drum. Compared with the traditional pressure sensor located at the bottom of the stirring drum, the weight detection of this structure is more accurate. The support-type weighing sensors 4 on both sides provide double support for the horizontal stirring drum 1, making it more stable and less prone to shaking or vibration. Moreover, the average value of the two weight values ​​detected by the two sensors is used as the accurate value inside the stirring drum. Compared with single sensor detection, the result is more accurate. Furthermore, when the results of the two sensors differ too much, the fault can be quickly and accurately identified, thereby enabling repair and avoiding misleading detection and excessive discharge error.

[0047] The support-type weighing sensor 4 detects the weight of the horizontal mixing drum 1 in real time and controls the rotation speed of the mixing shaft 2. In the pre-coating device, in order to accurately measure the amount of material dispensed each time, the support-type weighing sensor 4 weighs the horizontal mixing mechanism and its connected components after each material dispensing and spraying. The amount of material dispensed each time is strictly limited. For example, if the customer requires the amount of material dispensed each time to be 200g / h ± 20% of the deviation, then under the preset optimal condition, the amount of material dispensed per minute should be a constant value, and the deviation before and after should be controlled within the preset range. The weighing sensor performs a weighing measurement once per minute, and the measured weight should also be a constant value under ideal conditions. The deviation of this constant value should be within a preset range. Under ideal conditions, the multiple sets of measured data should form an almost linearly changing straight line. When the weighing value measured by the support-type weighing sensor 4 exceeds the preset range, i.e. the deviation is too large, the amount of material fed can be adjusted by adjusting the conveying speed of the feeding mechanism. However, if the conveying speed is adjusted to the fastest and the weighing value measured by the support-type weighing sensor 4 is still greater than the preset range, i.e. the amount of material fed is still too small, then the rotation speed of the stirring shaft 2 is increased from the uniform low speed level v1 to the high speed level v2, the feeding speed of the stirring mechanism 100 increases, and the amount of material fed by the feeding mechanism at the same speed increases, thereby achieving the purpose of adjusting and correcting the amount of material fed. In addition, if the powder in the mixing drum becomes uneven for some reason, a short-term increase in stirring speed can restore the weight of the powder in the drum to uniformity. The v2 time can be preset to maintain 5 minutes.

[0048] Because the structure of the horizontal mixing drum 1 and the single-shaft continuous webbed paddle 3 of this invention makes the mixing drum sufficiently stable, the weight detected by the sensor is accurate enough. Using this weight detection value as a signal to control the rotation speed of the mixing shaft 2 can, in turn, further balance the weight inside the mixing drum, improve the accuracy of the material feed (spraying amount), and keep it stable, slow, and efficient mixing. The two complement each other and influence each other. Under their combined action, they achieve a mixing quality and material feed accuracy control result that far exceeds that of their individual actions.

[0049] Furthermore, the two sides of the horizontal stirring drum 1 are vertically suspended on the support-type weighing sensor 4, and the difference between the height of the support-type weighing sensor 4 and the height of the stirring shaft 2 is less than 100mm, which can reduce the additional torque generated by stirring and improve the accuracy of the sensor's weighing detection.

[0050] In one embodiment, the feeding port can be located at the top of the horizontal mixing drum 1, and has a square structure with a length > 350 mm and a width > 260 mm, thereby increasing the effective utilization area of ​​the feeding port, facilitating manual feeding, and preventing feeding overflow.

[0051] In one embodiment, the paddles 3 are evenly arranged on the stirring shaft 2, the distance between two adjacent paddles 3 along the X direction is equal, and the included angle between the projections of two adjacent paddles 3 on the normal plane B is 360° / n, n≥2. This structure makes the paddles 3 evenly distributed, and can complete a full cycle of stirring over the entire axial length of the horizontal stirring drum 1, making the stirring more thorough, and the powder discharge at the tail end of the discharge port is more uniform and stable.

[0052] like Figure 6 , Figure 7 As shown, the present invention also protects a pre-coating device, including a housing 100 and a single-shaft continuous paddle agitator 200 as described above; the single-shaft continuous paddle agitator 200 is mounted inside the housing 100 and located on top of it.

[0053] In one embodiment, the pre-coating device further includes a double-helix feeding mechanism 300 installed within the housing 100. The double-helix feeding mechanism 300 is installed below the single-shaft continuous paddle mixing mechanism 200 and receives and transports the powder within the single-shaft continuous paddle mixing mechanism 200. Using the double-helix feeding mechanism 300, a large-volume, stable, continuous, and uniform feeding and transport effect can be achieved. Furthermore, the two screws of the double helix rotate relative to each other, and their teeth mesh with each other, which also provides a self-cleaning function.

[0054] In one embodiment, the pre-coating device further includes a feeding mechanism 400 installed inside the housing 100. The feeding mechanism 400 is located at the tail end of the double-screw feeding mechanism 300 and is used to draw powder under negative pressure and send it to the dust collector.

[0055] In one embodiment, such as Figure 8 As shown, ventilation louvers 101 are provided on the side wall of the outer shell 100 of the pre-coating device to ensure the pressure balance of the inner and outer cavities of the pre-coating device, and to prevent the weighing values ​​measured by the double-sided support-type weighing sensors 4 from deviating too much due to the excessive negative pressure set by the feeding mechanism 400, thereby improving the accuracy of the pre-coating device feeding.

[0056] The present invention has been described in the above-described embodiments; however, these embodiments are merely examples for implementing the present invention. It must be noted that the disclosed embodiments do not limit the scope of the present invention. Conversely, any modifications and refinements made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.

Claims

1. A pre-coating device, characterized in that: It includes an outer shell, a single-axis continuous fin paddle mixing mechanism, and a double-helix feeding mechanism. The single-axis continuous fin paddle mixing mechanism is installed inside the outer shell and located at its top. The double-helix feeding mechanism is installed below the single-axis continuous fin paddle mixing mechanism and receives and transports the powder inside the single-axis continuous fin paddle mixing mechanism. The single-shaft continuous paddle mixing mechanism includes a horizontal mixing drum, a mixing shaft, and paddles; the bottom sidewall of the horizontal mixing drum is arc-shaped and its axis extends along the X direction; the front end of the horizontal mixing drum along the X direction is provided with a feed inlet and the rear end along the X direction is provided with a discharge outlet; the mixing shaft is installed inside the horizontal mixing drum along the X direction; n paddles are installed on the mixing shaft, n≥2; the paddles include a support rod installed on the mixing shaft and a web-shaped blade installed at the rear end of the support rod. The cross-section A and the normal plane B of the stirring shaft are perpendicular to each other. The support rod is a sheet-like or thin plate-like structure. The angle between the support rod and the normal plane B is β1, 0°≤β1<90°. When the stirring shaft is driven to rotate, the support rod rotates accordingly and cuts the powder to reduce resistance and prevent the horizontal stirring drum from vibrating or shaking. The included angle between the webbed blades and the cut surface A is α2, where 0° < α2 < 90°. The webbed blades are web-like plates or sheets, and the outer edge of the raised side of the webbed blades is shaped like a polynomial spline difference curve that fits the inner wall of the horizontal mixing drum. When the stirring shaft is driven to rotate, the outer edge of the raised side of the webbed blades scrapes against the bottom arc plate of the horizontal mixing drum at equal intervals along the spline curve to clean the drum wall. The included angle α2 causes the webbed blades to push the powder on the outside inward and gather it during stirring, preventing the powder from accumulating and adhering to the drum wall. The angle between the webbed blades and the normal plane B along the X direction is β2, 0° < β2 < 90°. When the stirring shaft is driven to rotate, the webbed blades push the powder in the horizontal stirring drum to move along the X direction. The n webbed blades push the powder from the feed port along the X direction to continuously stir it under uneven force. Under the continuous pushing action of the webbed blades, the powder gradually moves laterally and slowly to the discharge port. The single-shaft continuous paddle mixing mechanism also includes two support-type weighing sensors. The two support-type weighing sensors are symmetrically installed on both sides of the horizontal mixing drum and the horizontal mixing drum is suspended inside the top of the pre-spraying device. The difference between the weight detected each time and the weight detected last time is the output of the horizontal mixing drum. The support-type weighing sensors detect the weight of the horizontal mixing drum in real time and control the rotation speed of the mixing shaft. When the weight detected by the two support-type weighing sensors is normal and the weight difference does not exceed the preset value, the paddle maintains a uniform low speed setting v1. When the weight detected by the two support-type weighing sensors is abnormal or the weight difference continues to exceed the preset value and cannot be corrected, the stirring speed of the paddle increases from the uniform low speed setting v1 to the high speed setting v2, the feeding speed of the single-shaft continuous paddle stirring mechanism increases, and the feeding amount of the double-helix feeding mechanism increases until it is corrected. When the powder in the horizontal mixing drum is uneven, the stirring speed is also increased to v2 for a short time until the powder is restored to uniformity.

2. The pre-coating device as described in claim 1, characterized in that: The horizontal stirring drum is vertically suspended on both sides by the support-type weighing sensor, and the difference between the height of the support-type weighing sensor and the height of the stirring shaft is less than 100mm.

3. The pre-coating device as described in claim 1, characterized in that: The angle β1 between the support rod and the normal plane B is 0°.

4. The pre-coating device as described in claim 1, characterized in that: The included angle α2 between the webbed blades and the cut surface A is in the range of 10°≤α2≤20°.

5. The pre-coating device as described in claim 1, characterized in that: The angle β2 between the webbed blades and the normal plane B along the X direction is in the range of 30°≤β2≤50°.

6. The pre-coating device as described in claim 1, characterized in that: The paddles are evenly arranged on the stirring shaft, with the distance between two adjacent paddles along the X direction being equal, and the included angle between the projections of two adjacent paddles onto the normal plane B being 360° / n, where n≥2.

7. The pre-coating device as described in claim 1, characterized in that: It also includes a material receiving and feeding mechanism installed inside the outer casing. The material receiving and feeding mechanism is located at the tail end of the double spiral feeding mechanism. The material receiving and feeding mechanism is used to draw powder under negative pressure and send it into the dust collector.

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