CN112892999A

CN112892999A - Foil coating device

Info

Publication number: CN112892999A
Application number: CN202110044312.2A
Authority: CN
Inventors: 马毅; 丁亚男; 苏夏
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2021-01-13
Filing date: 2021-01-13
Publication date: 2021-06-04
Anticipated expiration: 2041-01-13
Also published as: CN112892999B

Abstract

The invention provides a foil coating device which is used for coating a conveyed foil and comprises a feeding mechanism, a coating die head mechanism, an areal density detection mechanism and a control mechanism in an integral structure. The feeding mechanism is provided with a slurry storage unit and a pumping unit which is connected with the slurry storage unit and used for pumping slurry. The coating die head mechanism is provided with a coating die head, a plurality of feeding pipes and a backflow pipe, wherein the feeding pipes are connected with the pumping unit, the backflow pipe is connected with the slurry storage unit, the feeding pipes are arranged at intervals and are respectively connected with the adjusting valves in series, and coating openings of the coating die head are divided into a plurality of sections which are in one-to-one correspondence with the feeding pipes. The surface density detection mechanism is arranged corresponding to the foil to collect the surface density of the coated foil. The control mechanism is connected with the surface density detection mechanism, the pumping unit and each regulating valve. The foil coating device provided by the invention can adjust the coating surface density on line, effectively improves the coating operation efficiency, and has strong practicability.

Description

Foil coating device

Technical Field

The invention relates to the technical field of foil coating equipment, in particular to a foil coating device.

Background

With the deep implementation of the national sustainable development strategy, the lithium battery is a prominent member in the new energy industry, the development of the lithium battery is more and more emphasized by various social circles, and the lithium battery is applied to the daily life of people, especially the industries of digital products, automobiles and other electric tools.

Coating is an important process necessary in the production process of lithium batteries, and in popular terms, active substances are uniformly coated on a current collector (copper foil/aluminum foil) according to a certain weight, and the coated current collector (also called a pole piece or foil) can be used in the next process. The consistency of the coating surface density of the foil is a key index of the coating quality, is very important for improving the electrical performance and ensuring the safety of the battery, and the capacity of the battery is influenced if the consistency of the coating surface density of the positive electrode is poor, so that the electrical performance of the battery is not up to the standard; if the consistency of the negative coating surface density is poor, the interface of the battery pole piece is poor, and further safety accidents are caused.

Based on present lithium cell production process, when carrying out foil coating process, its self viscosity can have certain change along with the time variation, can produce the reunion if sometimes, perhaps also can be because of filtration system exists the filter effect not good sometimes again to lead to thick liquids mobility to worsen, influence the coating quality. Particularly, as the width of the foil material is larger and larger during coating, the consistency of the density of the coated surface of the foil material is difficult to ensure. However, the existing coating device mainly adjusts the coating surface density by adjusting a die head screw, adjusting the pump speed of a feeding pump or adjusting the feed and retraction of a die head, which is difficult to solve the above problems, cannot realize on-line adjustment of local coating surface density, and has poor adjustment efficiency and adjustment effect.

Disclosure of Invention

In view of the above, the present invention is directed to a foil coating apparatus, which can realize online adjustment of the local slurry supply amount on the coating surface, so as to effectively improve the consistency of the coating surface density and improve the coating efficiency.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a foil coating apparatus for coating a foil being conveyed, the foil coating apparatus comprising:

the feeding mechanism is provided with a slurry storage unit and a pumping unit which is connected with the slurry storage unit and is used for pumping the slurry;

the coating die head mechanism is provided with a coating die head, a plurality of feeding pipes and a plurality of return pipes, the feeding pipes are connected with the pumping unit, the return pipes are connected with the slurry storage unit and are arranged at intervals, the feeding pipes are respectively connected with regulating valves in series, the return pipes are connected with return valves in series, and coating ports of the coating die head are divided into a plurality of sections corresponding to the feeding pipes one to one;

an area density detection mechanism provided corresponding to the foil to collect an area density of the coated foil, the area density detection mechanism being configured to constitute respective collection of coating areas on the foil corresponding to the coating ports of the respective sections;

and the control mechanism is connected with the surface density detection mechanism, the pumping unit and each regulating valve, and is configured to respond to a detection signal of the surface density detection mechanism and output a driving signal to control the actions of the pumping unit and each regulating valve.

Furthermore, a pressure detection unit for detecting the pressure of the outlet of the pump is arranged in the pumping unit, and a filtering and iron removing unit is arranged in the pumping unit.

Furthermore, a slurry sensing unit for detecting the storage amount of the slurry is arranged in the slurry storage unit, and a vacuum pipeline for connecting an external vacuum pumping device is arranged on the slurry storage unit.

Further, the slurry storage unit adopts a storage tank, and the pumping unit adopts a screw pump.

Furthermore, each feeding pipe is connected in parallel to a collecting pipe, and the collecting pipe is connected with the pumping unit through a feeding pipe.

Further, each feeding pipe is connected to the back of the coating die head, and the feeding pipes are uniformly arranged at intervals.

Further, the surface density detection mechanism adopts a surface density measuring instrument.

Furthermore, the return pipe is connected to the coating die head at the middle part of the arrangement direction of the feeding pipes.

Further, the coating die mechanism also has a backing roll arranged corresponding to the coating opening of the coating die.

Furthermore, along the conveying direction of the foil, a rubber roller for supporting the foil is arranged at the downstream of the back roller, and the surface density detection mechanism is arranged corresponding to the foil between the back roller and the rubber roller.

Compared with the prior art, the invention has the following advantages:

(1) according to the foil coating device, the plurality of feeding pipes connected with the regulating valves in series are arranged at intervals, the coating opening of the coating die head is divided into a plurality of sections corresponding to the feeding pipes one by one, so that the regulation of the slurry supply quantity of the local coating surface of the foil can be realized, meanwhile, the control mechanism is connected with the surface density detection mechanism, the pumping unit and the regulating valves, so that the control mechanism can send driving signals to the pumping unit and the regulating valves after receiving detection signals sent by the surface density detection mechanism, the intelligent online regulation of the local slurry supply quantity of the coating surface is realized, the operation is simple and convenient, the regulation precision and the automation degree are high, and further, the consistency of the coating surface density and the coating operation efficiency are effectively improved.

Meanwhile, the surface density detection mechanism is configured to form separate collection of coating areas on the foil corresponding to the coating openings of all sections, so as to facilitate providing detection signals of local coating surface density to the control mechanism. In addition, based on the structural design of the foil coating device, a return pipe connected with the coating die head is further arranged in the device, and a return valve is connected to the return pipe in series, so that the recovery treatment and the reutilization of the slurry can be realized, and the practicability of the device can be effectively improved.

(2) The pressure detection unit is arranged in the pumping unit, so that the outlet pressure of the pump can be conveniently detected, and the feeding precision of the pumping unit can be conveniently adjusted; and a filtering and iron removing unit is arranged in the pumping unit to filter the slurry, so that the fineness of the slurry is in a required range, the agglomeration phenomenon is avoided, and the slurry is ensured to have good fluidity.

(3) The slurry sensing unit is arranged in the slurry storage unit, so that the slurry storage amount can be conveniently detected, the slurry storage unit can be conveniently fed in time, the sufficient slurry is ensured, and the normal coating operation is ensured; and set up the vacuum pipeline with external evacuating device on thick liquids storage unit, can carry out vacuum treatment to thick liquids storage unit, take out the tiny bubble in the thick liquids, guarantee not because of having the bubble in the thick liquids and cause the coating unusual in the coating process.

(4) The slurry storage unit adopts a storage tank, so that the structure is simple, the cost is low, and the implementation is easy; the pumping unit adopts a screw pump, has the advantages of simple structure, safe and reliable work, convenient use and maintenance, continuous and uniform liquid outlet, stable pressure and the like, and can effectively control the feeding precision of the slurry.

(5) The collecting pipes connected with the pumping units are arranged, the feeding pipes are connected in parallel to the collecting pipes, slurry can be uniformly distributed into the feeding pipes after passing through the buffering effect of the collecting pipes, the adjustment of the slurry supply amount in the feeding pipes is facilitated, and the adjustment of the local slurry supply amount of the coating surface of the foil is further facilitated.

(6) The feeding pipes are uniformly arranged at the back of the coating die head at intervals, correspondingly, the coating ports of the coating die head can be distributed into multiple sections which are uniformly arranged at intervals, so that the coating local area of the foil can be uniformly divided in the width direction, the realization of operations such as uniform coating, local coating surface density detection, local coating surface slurry supply amount adjustment and the like is facilitated, and the using effect of the device is further improved.

(7) The surface density detection mechanism adopts a surface density measuring instrument, can realize non-contact on-line detection, and the surface density measuring instrument also has the advantages of high measuring speed, small measuring error, strong real-time performance and the like.

(8) The backflow pipe is connected to the coating die head in the middle of the arrangement direction of the feeding pipes, the structure is reasonable, and the backflow of slurry in the coating die head through the backflow pipe is facilitated.

(9) The back roll and the rubber roll are matched for use, so that the foil is conveniently supported, the uniform conveying of the foil is realized, and meanwhile, the surface density detection mechanism is arranged between the back roll and the rubber roll, so that the structure is reasonable, and the arrangement is convenient.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a foil coating apparatus according to an embodiment of the present invention;

fig. 2 is a schematic partial structural view of a foil coating apparatus according to an embodiment of the present invention;

FIG. 3 is a scattering diagram of the surface density of a foil coating apparatus after coating in the prior art;

fig. 4 is an area density scattergram of a foil coating apparatus according to an embodiment of the present invention after coating;

description of reference numerals:

1. a foil material; 2. a slurry storage unit; 3. a pumping unit; 4. a coating die head; 5. feeding pipes; 501. a first feeding pipe; 502. a second feeding pipe; 503. a third feeding pipe; 504. a fourth feeding pipe;

6. a return pipe; 7. adjusting a valve; 701. a first regulating valve; 702. a second regulating valve; 703. a third regulating valve; 704. a fourth regulating valve;

8. a reflux valve; 9. an areal density detection mechanism; 10. a control mechanism; 11. a manifold; 12. a feed pipe; 13. a backing roll; 14. and (4) a rubber roller.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it should be noted that, if terms indicating orientation or positional relationship such as "upper", "lower", "inner", "back", etc. appear, they are based on the orientation or positional relationship shown in the drawings and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the appearances of the terms first, second, etc. in this specification are not necessarily all referring to the same item, but are to be construed as indicating or implying any particular importance.

In addition, in the description of the present invention, the terms "mounted," "connected," and "connecting" are to be construed broadly unless otherwise specifically limited. For example, the connection can be fixed, detachable or integrated; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. To those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in conjunction with specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The present embodiment relates to a foil coating apparatus for coating a foil 1 being conveyed and capable of realizing online adjustment of a local slurry supply amount to a coating surface. It should be noted that the width of the foil 1 is generally 400-1500mm, the thickness of the foil 1 is 6-14 μm for the positive electrode, and the thickness of the foil 1 is 4-12 μm for the negative electrode. The slurry related to this embodiment generally has a solid content of 45-85% and a viscosity of 3000-; the solid content of the cathode slurry is 30-60%, and the viscosity is 2000-9000 cP.

Of course, in addition to the general setting of the foil 1 and the slurry, the foil coating apparatus of the present embodiment can be used for coating the foil 1 of other specifications and the slurry of other components according to design requirements, and is not limited herein. In addition, the structures of the foil coating device not described in this embodiment can refer to the common structural parts in the prior art, and are not described herein again.

As shown in fig. 1 and 2, the foil coating apparatus described above includes a feeding mechanism, a coating die 4 mechanism, an areal density detection mechanism 9, and a control mechanism 10. Wherein the feeding mechanism has a slurry storage unit 2, and a pumping unit 3 connected to the slurry storage unit 2 for pumping the slurry.

The coating die head 4 mechanism is provided with a coating die head 4, a plurality of feeding pipes 5 and a plurality of return pipes 6 which are connected with the coating die head 4, the feeding pipes 5 are connected with the pumping unit 3, the return pipes 6 are connected with the slurry storage unit 2, the feeding pipes 5 are arranged at intervals and are respectively connected with a regulating valve 7 in series, the return pipes 6 are connected with return valves 8 in series, and the coating openings of the coating die head 4 are divided into a plurality of sections which are in one-to-one correspondence with the feeding pipes 5.

Meanwhile, the area density detection mechanism 9 is provided corresponding to the foil 1 to collect the area density of the coated foil 1, and the area density detection mechanism 9 is configured to constitute the individual collection of the coating areas on the foil 1 corresponding to the respective coating ports. The control mechanism 10 is connected with the area density detection mechanism 9, the pumping unit 3 and each regulating valve 7, and the control mechanism 10 is configured to output a drive signal to control the actions of the pumping unit 3 and each regulating valve 7 in response to a detection signal of the area density detection mechanism 9.

Based on the above design concept, an exemplary structure of the foil coating apparatus of the present embodiment is shown in fig. 1 to 4, and as described above, the feeding mechanism has the slurry storage unit 2, and the pumping unit 3 connected to the slurry storage unit 2 for pumping the slurry. Preferably, the pumping unit 3 is provided with a pressure detection unit for detecting the outlet pressure of the pump, so as to detect the outlet pressure of the pump and facilitate the adjustment of the feeding precision of the pumping unit 3; and a filtering and iron removing unit is arranged in the pumping unit 3 to filter the slurry, so that the fineness of the slurry is in a required range, the agglomeration phenomenon is avoided, and the slurry is ensured to have good fluidity.

In addition, the pressure detection unit and the filtering iron removal unit are not explicitly shown in the figure, the pressure detection unit can refer to the specific structure of a conventional pressure sensor, and the filtering iron removal unit can adopt a conventional filtering iron removal system. It is worth mentioning that when the filtering and de-ironing unit is actually used, the filtering parameter of the filtering and de-ironing unit can be set according to the fineness requirement required by the slurry, generally 80-250 meshes, and the de-ironing size is more than or equal to 10000 gauss.

In the practical application process, the slurry storage unit 2 adopts a storage tank, has a simple structure and low cost, is easy to realize, is generally set to be 100 plus 200L, is made of stainless steel 304, is subjected to polishing treatment in the storage tank, and is plated with wear-resistant materials such as ceramic and WC (tungsten carbide) so as to improve the comprehensive use performance of the storage tank; wherein 304 stainless steel is a common material in stainless steel, and has a density of 7.93g/cm³It has the characteristics of high temperature resistance, good processing performance, high toughness and the like.

Similarly, as a preferred mode of practical application, the pumping unit 3 adopts a screw pump, has the advantages of simple structure, safe and reliable work, convenient use and maintenance, continuous and uniform liquid outlet, stable pressure and the like, can provide power for the transportation of slurry, and effectively controls the feeding precision of the slurry; specifically, the feeding pressure precision can be controlled within +/-0.5% by using a screw pump.

As a further improvement, in order to facilitate the detection of the storage amount of the slurry, a slurry sensing unit for detecting the storage amount of the slurry is arranged in the slurry storage unit 2, so that the slurry is fed into the slurry storage unit 2 in time, the sufficient slurry is ensured, and the normal operation of the coating operation is ensured; and the slurry storage unit is provided with a vacuum pipeline externally connected with a vacuumizing device, so that the slurry storage unit can be subjected to vacuum treatment, tiny bubbles in the slurry are pumped out, and abnormal coating caused by the bubbles in the slurry is avoided in the coating process.

It should be noted that the slurry sensing unit, the vacuum pipeline and the vacuum pumping device are not shown in the drawings, and the structure thereof can be seen in the common structure with corresponding functions in the prior art. When the vacuum-pumping device is used, the time of the vacuum-pumping operation can be set according to the actual requirement, and the vacuum value is generally set to be more than or equal to-60 kpa, so that a relatively good vacuum treatment effect is achieved.

In this embodiment, as shown in fig. 1 and fig. 2, as also described above, the coating die head 4 mechanism has a coating die head 4, and a feeding pipe 5 and a return pipe 6 connected to the coating die head 4, the feeding pipe 5 is connected to the pumping unit 3, the return pipe 6 is connected to the slurry storage unit 2, the feeding pipes 5 are arranged at intervals, and are respectively connected in series with a regulating valve 7, the return pipe 6 is connected in series with a return valve 8, and the coating ports of the coating die head 4 are divided into multiple sections corresponding to the feeding pipes 5 one to one.

The coating port is provided on the left side of the coating die 4 shown in fig. 1, and the feed pipe 5 and the return pipe 6 are provided on the right side of the coating die 4 shown in fig. 1. Further, each of the regulating valves 7 can independently regulate its own opening degree for regulating the slurry supply amount of the coating die 4; the return valve 8 can also adjust its opening for controlling the flow rate of the slurry return.

It should be noted that the length of the coating die 4 in this embodiment is preferably 1000mm, the material of the body is stainless steel 304 grade or more, the processing parallelism is 4 μm, the smoothness is controlled within 0.2s, and the installation levelness is 0.005mm/m, so as to obtain relatively excellent use effect. Of course, the length of the coating die 4 can be adjusted according to the actual situation, except that the coating die is set to 1000 mm.

Meanwhile, the feeding pipe 5 and the collecting pipe 11 are preferably set to be 3-6 inches in pipe diameter, the material is 304 stainless steel, the interior of the feeding pipe is polished, and the feeding pipe 5 and the collecting pipe 11 are plated with wear-resistant materials such as ceramic and WC, so that the comprehensive use performance of the feeding pipe 5 and the collecting pipe 11 is improved; the return pipe 6 is also preferably set to be 1.5-3 inches in pipe diameter, made of 304 stainless steel, polished inside and plated with wear-resistant materials such as ceramic and WC, so as to improve the comprehensive use performance of the return pipe 6.

For convenience of description, in the state shown in fig. 1 and 2, the feeding pipes 5 are named as a first feeding pipe 501, a second feeding pipe 502, a third feeding pipe 503 and a fourth feeding pipe 504 from front to back, and correspondingly, the regulating valves 7 are respectively a first regulating valve 701, a second regulating valve 702, a third regulating valve 703 and a fourth regulating valve 704, the coating opening is divided into a first section, a second section, a third section and a fourth section, and similarly, the foil 1 to be coated is divided into an a area, a B area, a C area and a D area in the width direction. Also, the first, second, third and fourth segments, and the a, B, C and D regions described herein are not explicitly shown in the figures.

As a further arrangement, as shown in fig. 1 and 2, each of the upper tubes 5 is connected in parallel to a collecting pipe 11, and the collecting pipe 11 is connected to the pumping unit 3 through a feeding tube 12, so that the slurry is uniformly distributed to each of the upper tubes 5 after passing through the buffering function of the collecting pipe 11, and the adjustment of the slurry supply amount in each of the upper tubes 5 is facilitated, thereby being more beneficial to the adjustment of the local slurry supply amount on the coating surface of the foil 1.

As shown in fig. 1 and 2, each feeding pipe 5 is connected to the back of the coating die head 4, i.e. the right side of the illustrated coating die head 4, and the feeding pipes 5 are uniformly spaced, it can be understood that the coating openings of the coating die head 4 are distributed into a plurality of sections uniformly spaced, i.e. the first section, the second section, the third section and the fourth section have equal width dimensions, corresponding to the feeding pipes 5 described herein one to one; in addition, in the division of the foil 1, the area A, the area B, the area C and the area D are also divided equally, so that the operations of uniform coating, local coating surface density detection, local coating surface slurry supply amount adjustment and the like can be realized, and the using effect of the device is further improved.

And as a preferred embodiment, as shown in fig. 1, the return pipe 6 is connected to the coating die head 4 at the middle part of the arrangement direction of the feeding pipes 5, that is, the return pipe 6 is arranged at the middle part between the second feeding pipe 502 and the third feeding pipe 503, so that the structure is reasonable, and the slurry in the coating die head 4 can be returned through the return pipe 6.

In the present embodiment, as shown in fig. 1, the above-mentioned area density detection mechanism 9 is provided corresponding to the foil 1 to collect the area density of the coated foil 1, and the area density detection mechanism 9 is configured to constitute the respective collection of the coating areas corresponding to the coating ports of the respective sections on the foil 1, that is, the area density detection mechanism 9 is configured to constitute the respective collection of the areas a, B, C, and D on the foil 1.

Preferably, the surface density detection mechanism 9 adopts a surface density measuring instrument, especially a beta-ray surface density measuring instrument, so that non-contact online detection can be realized, and the surface density measuring instrument also has the advantages of high measurement speed, small measurement error, strong real-time performance and the like.

It should be noted that, in the actual measurement process, the sampling speed is typically 4000/s, the response time is 1 ms, the static accuracy is ± 0.08%, and the linearity is ± 0.02%, and after the measuring apparatus samples the ABCD four regions respectively, the measuring apparatus calculates the average value of the measurement in each region respectively, and transmits the measurement information to the control mechanism 10 to evaluate whether the coating surface density of each region meets the standard, so that the control mechanism 10 takes corresponding measures to adjust the coating operation.

In the present embodiment, as shown in fig. 1, the control mechanism 10 is connected to the surface density detection mechanism 9, the pumping unit 3 and each of the regulating valves 7, and the control mechanism 10 is configured to output a driving signal to control the operations of the pumping unit 3 and each of the regulating valves 7 in response to a detection signal of the surface density detection mechanism 9.

Of course, the control mechanism 10 herein has the main functions of signal acquisition, data processing and command sending, and the specific structure thereof can refer to the common structure in the prior art. And it is understood that the above-mentioned control mechanism 10 is connected with the surface density detection mechanism 9, the pumping unit 3 and each regulating valve 7 through signal lines, which are not shown in the figure; the control means 10 is also connected to the return valve 8 in the above-described manner so as to output a signal command for the slurry return processing.

In addition, referring to fig. 1, the coating die 4 mechanism in this embodiment further has a back roller 13 disposed corresponding to the coating opening of the coating die 4, and a rubber roller 14 for supporting the foil 1 is disposed downstream of the back roller 13 along the conveying direction of the foil 1, and the areal density detecting mechanism 9 is disposed corresponding to the foil 1 between the back roller 13 and the rubber roller 14.

As can be understood here, the foil 1 is convenient to bear and the uniform-speed conveying of the foil 1 is realized by the matching use of the back roll 13 and the rubber roll 14, and meanwhile, the surface density detection mechanism 9 is arranged between the back roll 13 and the rubber roll 14, so that the structure is reasonable, and the arrangement of the whole structure of the device is convenient.

In the foil coating device of the embodiment, in the coating operation, the parameter of the pumping unit 3 is set to a standard value required by the coating surface density, and the standard value is used for carrying out slurry conveying and feeding, when the surface density detection mechanism 9 detects that the density of each area of the coating surface is abnormal (here, preferably, when the foil 1 is continuously coated and produced for 2m, the abnormality is found), for example, the measured value of the area density in the area a exceeds a specified upper limit value, and the measured value of the area density in the area C is lower than a specified lower limit value, the surface density detection mechanism 9 transmits the acquired data information to the control mechanism 10 through a signal line.

After the collected data information is transmitted to the control mechanism 10, the control mechanism 10 rapidly makes an instruction through data analysis and processing, transmits the instruction to the corresponding first regulating valve 701 and third regulating valve 703 through signal lines, and simultaneously transmits the relevant instruction to the pumping unit 3. The specific process is that according to the difference value that the measured value of the area density of the area A exceeds the standard value of the area density, the control mechanism 10 outputs an instruction for reducing the opening degree of the first regulating valve 701 so as to reduce the flow rate of the slurry flowing to the area A; according to the difference value that the measured value of the area density of the area B is lower than the standard value of the area density, the control mechanism 10 outputs a command to increase the opening of the third regulating valve 703, so as to increase the flow rate of the slurry flowing to the area B.

Meanwhile, the control mechanism 10 can also analyze the overall increased or decreased supply amount of the slurry, and when the overall slurry supply flow needs to be increased, the control mechanism 10 drives the rotating speed of the pumping unit 3 to be increased so as to increase the overall slurry supply amount of the feeding mechanism; when the overall slurry supply flow needs to be reduced, the control mechanism 10 drives the rotational speed of the pumping unit 3 to be reduced to reduce the overall slurry supply amount of the feeding mechanism.

Finally, the measured value of the areal density of the coating can be made to swing around the standard value under the operation of the whole apparatus, as shown in fig. 3 and 4, in contrast, the accuracy of the areal density of the coating of the foil 1 after the coating operation of the apparatus can be up to ± 1% and more than ± 1.5% ± 2% which can be achieved by the prior art, wherein the actual areal density values shown in fig. 3 and 4 correspond to the measured values of the areal density in the present embodiment, and the median difference of the areal density corresponds to the standard value of the areal density in the present embodiment. And, foil coating device in this embodiment has realized the intelligent on-line adjustment of scribbling areal density, compares just adjustable mode after prior art need shut down, has greatly promoted production efficiency.

It should be noted that the relationship between the difference between the increase or decrease in the coating surface density and the opening of each regulating valve 7 is: s2 kR²(α -1/2sin α), wherein S is a coating surface density increase and decrease value, k is a coefficient related to slurry fluidity, and k is 0.9-1.1 when the slurry fluidity is good, and is 0.4-0.9 when the slurry fluidity is poor; r is the opening radius of the clearance valve; alpha is the rotation opening.

The foil coating device of this embodiment arranges a plurality of material loading pipes 5 that are connected with governing valve 7 in series through the interval to divide into the coating mouth of coating die head 4 with each material loading pipe 5 multistage one-to-one, can realize the regulation to the thick liquids supply quantity of the local coating face of foil 1, simultaneously, through being connected control mechanism 10 with face density detection mechanism 9, pumping unit 3 and each governing valve 7, make control mechanism 10 behind the detection signal that receiving face density detection mechanism 9 sent, can send drive signal to pumping unit 3 and each governing valve 7, realize the intelligent on-line adjustment to the local thick liquids supply quantity of coating face, easy and simple to handle, regulation precision and degree of automation are high, and then effectively promote coating face density uniformity and coating operating efficiency.

Wherein the areal density detection means 9 are further configured to constitute a separate acquisition of the coating areas on the foil 1 corresponding to the coating openings of the respective section, in order to facilitate the provision of a detection signal of the local coating areal density to the control means 10. In addition, based on the structural design of the foil coating device, the device is also internally provided with a return pipe 6 connected with the coating die head 4, and the return valve 8 is connected on the return pipe 6 in series, so that the recovery treatment and the reutilization of the slurry can be realized, and the practicability of the device can be effectively improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A foil coating device for coating a foil (1) being conveyed, characterized by: the foil coating device includes:

a feed mechanism having a slurry storage unit (2) and a pumping unit (3) connected to the slurry storage unit (2) for pumping the slurry;

the coating die head (4) mechanism is provided with a coating die head (4), feeding pipes (5) and return pipes (6) which are connected with the coating die head (4), the feeding pipes (5) are connected with the pumping unit (3), the return pipes (6) are connected with the slurry storage unit (2), the feeding pipes (5) are arranged at intervals and are respectively connected with regulating valves (7) in series, return valves (8) are connected on the return pipes (6) in series, and coating ports of the coating die head (4) are divided into a plurality of sections which correspond to the feeding pipes (5) one by one;

an areal density detection mechanism (9), the areal density detection mechanism (9) being provided in correspondence with the foil (1) to collect an areal density of the foil (1) after coating, and the areal density detection mechanism (9) being configured to constitute a separate collection of coating areas on the foil (1) corresponding to the coating ports of the respective sections;

and the control mechanism (10) is connected with the surface density detection mechanism (9), the pumping unit (3) and each regulating valve (7), and the control mechanism (10) is configured to respond to a detection signal of the surface density detection mechanism (9) and output a driving signal to control the actions of the pumping unit (3) and each regulating valve (7).

2. Foil coating device according to claim 1, wherein: the pumping unit (3) is internally provided with a pressure detection unit for detecting the pressure of the outlet of the pump, and the pumping unit (3) is internally provided with a filtering and iron removing unit.

3. Foil coating device according to claim 1, wherein: the slurry storage unit (2) is internally provided with a slurry sensing unit for detecting the storage amount of the slurry, and the slurry storage unit is provided with a vacuum pipeline externally connected with a vacuumizing device.

4. Foil coating device according to claim 1, wherein: the slurry storage unit (2) adopts a storage tank, and the pumping unit (3) adopts a screw pump.

5. Foil coating device according to claim 1, wherein: the feeding pipes (5) are connected in parallel to a collecting pipe (11), and the collecting pipe (11) is connected with the pumping unit (3) through a feeding pipe (12).

6. Foil coating device according to claim 1, wherein: the feeding pipes (5) are connected to the back of the coating die head (4), and the feeding pipes (5) are uniformly arranged at intervals.

7. Foil coating device according to claim 1, wherein: the surface density detection mechanism (9) adopts a surface density measuring instrument.

8. Foil coating device according to claim 1, wherein: the return pipe (6) is connected to the coating die head (4) in the middle of the arrangement direction of the feeding pipes (5).

9. Foil coating device according to any one of claims 1 to 8, wherein: the coating die (4) mechanism also has a backing roll (13) arranged corresponding to the coating opening of the coating die (4).

10. Foil coating device according to claim 9, wherein: along the direction of delivery of foil (1), in the low reaches of backing roll (13) is equipped with in order to support rubber roll (14) of foil (1), surface density detection mechanism (9) correspond back roll (13) with between rubber roll (14) foil (1) are arranged.