CN115739548A - Swing-roller-free diaphragm coating machine for lithium battery and control method - Google Patents

Abstract

A lithium battery swinging-roller-free diaphragm coating machine and a control method thereof are provided, wherein the coating machine comprises a diaphragm, an unreeling device, a machine head, a discharging device, a reeling device, a data acquisition device and a control device; the diaphragm is output by the unwinding device and sequentially passes through the machine head, the discharging device and the winding device; the data acquisition device is arranged in the unwinding device, the machine head or the discharging device; the control device is electrically connected with the data acquisition device; the method comprises the following steps: setting a target tension value of a diaphragm, and calculating a preset torque according to the target tension value; acquiring a diaphragm tension value in real time, and calculating tension deviation values at multiple moments based on the target tension value; calculating a torque control increment according to the tension deviation values at the multiple moments; the invention realizes high-precision control by adjusting the tension of the diaphragm through the torque, realizes the adjustment of the contact angle of the diaphragm and each roller based on the swinging-free roller, greatly reduces the possibility of large wrap angle and avoids wrinkling.

Description

A Lithium Battery Swing Roller Diaphragm Coating Machine and Control Method

technical field

The invention relates to the technical field of diaphragm coating machines, and more specifically relates to a lithium battery swing-free diaphragm coating machine and a control method.

Background technique

At present, the general lithium battery diaphragm coating machine in the market adopts the swing roller for tension control. On the one hand, the tension is controlled by controlling the thrust of the cylinder through compressed air pressure, and on the other hand, the position of the swing roller is detected by a potentiometer or a position sensor to control the unwinding. , The speed of the traction and winding motor is stabilized at the set position by PID adjustment method, so as to ensure that the tension of the diaphragm is constant when the coating machine is running. Due to the pendulum structure, the tension of the pendulum roll is close to 180° at the position of unwinding and traction of the coating machine, which is easy to occur when the diaphragm with a thickness of less than 7 μm passes through the roll with a large wrap angle. Wrinkles, and the pendulum roller controls the tension by swinging in a pendulum manner instead of linear motion, which makes the output tension of the pendulum roller different when it is in different positions, resulting in a significant reduction in the accuracy of diaphragm tension control.

There are also other coating machines on the market that use magnetic powder clutches to control tension. Although this method does not require swing rollers, the magnetic powder clutches have low control precision and slow response speed, so they are not suitable for use on diaphragm coating machines.

Therefore, how to provide a lithium battery swing-free separator coating machine and a control method to improve tension control precision and improve coating quality is an urgent problem to be solved by those skilled in the art.

Contents of the invention

In view of this, the present invention provides a separator coating machine without a swing roller for lithium batteries, which can solve surface defects such as wrinkling that are easily caused by the large wrap angle belt threading required by the swing roller control tension structure of the separator coater, and reduce the The difficulty of control is required, and a torque control method is proposed to improve the control accuracy.

In order to achieve the above object, the present invention adopts the following technical solutions:

A lithium battery swing-free diaphragm coating machine, comprising: a diaphragm, an unwinding device, a machine head, a discharging device, a winding device, a data acquisition device and a control device;

The diaphragm is output by the unwinding device, passing through the machine head, the discharging device and the winding device in sequence;

The data acquisition device is arranged inside the unwinding device, the machine head or the discharging device;

The control device is electrically connected with the data acquisition device.

Further, the unwinding device includes an unwinding roller, a first passing roller and a first connecting group of rollers arranged at the outlet end of the unwinding roller; the first passing roller is electrically connected to a first servo motor; the The diaphragm is output to the machine head through the first passing roller and the first connecting group of rollers, and the contact angle between the diaphragm and the first passing roller and the first connecting group of rollers is less than or equal to 90°.

Further, the data collection device includes an ultrasonic sensor installed on the unwinding roller, the ultrasonic sensor is electrically connected to the control device, and is used to detect the diameter of the coil on the unwinding roller.

Further, the machine head includes a reference roll, a coating roll, a first intermediate roll and a second intermediate roll distributed on both sides of the coating roll, and a second passing roll arranged at the outlet of the machine head;

The reference roller, the first intermediate roller and the second intermediate roller are respectively connected with a second servo motor and a third servo motor; the second servo motor and the third servo motor are electrically connected to the control device connect;

The diaphragm is conveyed by the reference roller, passing through the first intermediate roller, the coating roller, the second intermediate roller and the second passing roller in sequence, and the diaphragm is connected to the coating roller, The contact angles of the first intermediate roll, the second intermediate roll, and the second pass roll are all less than or equal to 90°.

Further, it also includes a second connecting group of rollers connecting the first connecting group of rollers and the reference roller, the second connecting group of rollers is used to adjust the transmission angle of the diaphragm, and expand the distance between the diaphragm and the Wrap angle of reference roll.

Further, the reference roller, the first intermediate roller and the second intermediate roller are respectively connected with a second servo motor, a third servo motor and a fourth servo motor; the second servo motor and the third servo motor are connected with The control device is electrically connected.

Further, a flattening roller is further provided between the reference roller and the first intermediate roller, and the flattening roller has a concave-convex surface for flattening the diaphragm.

Further, the data acquisition device includes a plurality of tension sensors, and the plurality of tension sensors are respectively installed between the unwinding device and the machine head, between the machine head and the discharge device, and between the machine head and the discharge device. Between the discharge device and the winding device, it is used to collect the tension of the diaphragm.

Further, the data acquisition device includes a plurality of ultrasonic sensors, and a plurality of the ultrasonic sensors are respectively installed in the unwinding device, the discharging device and the winding device for collecting the coil diameter .

Further, a baking device is also included. After the diaphragm is coated by the machine head, it enters the baking device for drying, and the dried diaphragm enters the discharge device.

A method for controlling a lithium battery swing-free diaphragm coater, comprising the following steps:

Set the diaphragm target tension value, and calculate the preset torque according to the target tension value;

collecting diaphragm tension values in real time, and calculating tension deviation values at multiple moments based on the target tension values;

Torque control increments are calculated according to the tension deviation values at the multiple moments.

Further, the real-time collection of diaphragm tension values includes:

Collect the diaphragm tension value between the unwinding device and the machine head;

Collect the diaphragm tension value between the machine head and the discharge device;

Collect the diaphragm tension value between the discharge device and the winding device.

Further, the steps also include:

Set the friction parameter and get the coil diameter;

Calculate the motor torque value according to the target tension value, the friction parameter and the coil diameter, and input it into the servo motor.

Further, the coil diameter includes the coil diameter of the unwinding roller, the coil diameter in the discharge traction roller and/or the coil diameter of the take-up roller.

Beneficial effects of the present invention:

It can be seen from the above-mentioned technical solutions that, compared with the prior art, the present invention discloses a lithium battery separator coating machine without a swing roller and a control method, which can solve the problem of the diaphragm coater in the tension control structure of the swing roller. Surface defects such as wrinkling that are easily caused by corner wear belts reduce the need for control difficulty, and a torque control method is proposed to improve control accuracy; the present invention realizes high precision and high precision of tension control through tension monitoring and coil diameter monitoring respectively. Stability under precision.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Figure 1 is a schematic diagram of the structure of a lithium battery non-swing roller separator coating machine provided by the embodiment of the present invention;

FIG. 2 is a schematic diagram of a tension control method provided in an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1, the embodiment of the present invention discloses a lithium battery non-swing roller diaphragm coating machine, including: diaphragm, unwinding device, machine head, discharging device, winding device, data acquisition device and control device;

The diaphragm is output by the unwinding device, and passes through the machine head, the discharging device and the winding device in turn;

The data acquisition device is set inside the unwinding device, machine head or discharging device;

The control device is electrically connected with the data acquisition device.

In one embodiment, it also includes a display device, such as a touch screen; the touch screen is electrically connected with the control device for realizing human-computer interaction.

In one embodiment, the unwinding device includes an unwinding roller, a first passing roller and a first connecting group of rollers arranged at the outlet end of the unwinding roller; the first passing roller is electrically connected to a first servo motor; the diaphragm passes through the first The passing roller and the first connecting group of rollers are output to the machine head, and the contact angle between the diaphragm and the first passing roller and the first connecting group of rollers is less than or equal to 90°.

Specifically, in Figure 1, the diaphragm is released from the unwinding roller, and then passes through the first connecting group of rollers consisting of passing roller 1, passing roller 2, and passing roller 3. During the transmission process, the diaphragm passes through passing roller 1, passing roller 2 and passing roller 3 are opposite to the diaphragm transmission direction, and the contact angles between all passing rollers inside the unwinding device and the diaphragm are less than or equal to 90°.

And if the diaphragm adopts the pendulum roller threading method, the substrate must be opposite to the running direction of the diaphragm when the pendulum roller is threaded through the roller, so the contact angle between the pendulum roller and the diaphragm must be greater than 90°, which will easily cause the diaphragm to run. Wrinkle in.

In this embodiment, the first servo motor controls the first passing roller to generate a torque opposite to the diaphragm transmission direction on the diaphragm. During operation, the head reference roller transports the diaphragm forward at a set speed. When the head reference roller When the force generated by the tension is greater than the tension value set for unwinding, the unwinding roller will be pulled and rotated by the diaphragm, and the torque of the unwinding roller driving the servo motor is controlled by the PLC (programmable logic controller) according to the touch screen (man-machine interface) ) is controlled according to open loop mode or closed loop mode.

In one embodiment, the data collection device includes a tension sensor, and the tension sensor collects the tension of the diaphragm, and realizes closed-loop mode control in combination with the control device.

Specifically, the control device is PLC, and the unwinding mechanism is equipped with a tension sensor to detect the physical quantity of the diaphragm unwinding tension in real time and output it to the PLC. The PLC converts the physical quantity detected by the unwinding tension sensor into an actual tension value. When the value detected by the tension sensor deviates from the touch screen When the tension value is set above, the PLC adjusts the torque of the servo motor driven by the unwinding roller in real time through the program operation to achieve precise tension control. The PLC compares the tension value set on the touch screen with the sampling value in real time through the program operation and adjusts the unwinding roller in real time The driven torque value is output to the servo motor driver, and then the driver automatically controls the torque of the unwinding roller to drive the servo motor according to the torque physical quantity given by the PLC to generate precise tension on the diaphragm, so that the diaphragm can maintain unwinding with high precision and constant tension. tension.

In another embodiment, the tension sensor is installed in the passing roller in the machine head, in the discharging device or in the winding device, and is used to detect the tension of the diaphragm. It can realize the tension control of each stage of the diaphragm, and install the tension sensor through the roller in the machine head to realize the tension detection of the diaphragm between the unwinding device and the machine head, and realize the tension control by combining the control device and the installed servo motor; A tension sensor is installed in the device to detect the tension of the diaphragm between the rollers inside the machine head and the rollers inside the discharge device, and the tension control is realized by combining the control device and the correspondingly installed servo motor.

In one embodiment, the data acquisition device includes an ultrasonic sensor installed on the unwinding roller, and the ultrasonic sensor is electrically connected to the control device for detecting the diameter of the coil on the unwinding roller.

In this embodiment, the open-loop mode control is realized according to the diameter of the coil collected by the ultrasonic sensor in combination with the control device.

Specifically, the unwinding roller uses an ultrasonic sensor to detect the diameter of the unwinding coil in real time. Since the unwinding coil is being conveyed forward during the coating process, the diameter of the coil will gradually decrease during the conveying process. At this time, it is necessary to adjust the torque of the unwinding roller drive servo motor in real time according to the diameter change of the unwinding reel through PLC (programmable controller) operation to achieve precise tension control. PLC (programmable controller) is set on the touch screen through program operation The setting: (tension + friction force set on the touch screen) * unwinding coil diameter = servo motor torque value, output to the servo motor driver, and then the driver automatically controls the unwinding according to the torque physical quantity given by the PLC (programmable logic controller). The winding roller drives the torque of the servo motor to generate precise tension on the diaphragm. Since the diameter of the reel is a linear variable, the torque value output to the servo motor by the program calculation result also changes linearly, so that the base film avoids signal interference from the sensor, Or tension fluctuations caused by faults, which have a great protective effect on diaphragms that require low tension.

In another implementation, in addition to detecting the diameter of the coil in the unwinding device, the ultrasonic sensor can also be installed in the diameter of the coil in the discharge device or the diameter of the coil in the winding device or two or more of the above occasions Combined with the application, combined with the program in the control device to realize the open-loop mode tension control in each structure.

In one embodiment, the machine head includes a reference roll, a coating roll, a first intermediate roll and a second intermediate roll distributed on both sides of the coating roll, and a second passing roll arranged at the exit of the machine head;

The diaphragm is conveyed by the reference roller, passing through the first intermediate roller, the coating roller, the second intermediate roller and the second passing roller in sequence, and the separation between the diaphragm and the coating roller, the first intermediate roller, the second intermediate roller, and the second passing roller The contact angles are all less than or equal to 90°.

The reference roller, the first intermediate roller and the second intermediate roller are respectively connected with a second servo motor, a third servo motor and a fourth servo motor; the second servo motor and the third servo motor are electrically connected with the control device. Among them, the reference roller is the passing roller 6, and the passing roller 6 is driven by the second servo motor, which provides forward power for the diaphragm transmission of the whole machine through the second servo motor; the first intermediate roller is the passing roller 8 and the second intermediate roller is the passing roller 10 are respectively driven by the third servo motor and the fourth servo motor, which are used to realize the tension control and ensure the stable tension of the working area of the first intermediate roller and the second intermediate roller during the coating process; the passing roller 8 ensures the tension between the diaphragm and the roller. Change the direction while changing the angle, so that the diaphragm is in contact with the roller 9 anilox roller vertically upward for coating, and the passing roller 10 is an adsorption roller to control the tension of the diaphragm in the coating area; The gravure roll sticks the slurry in contact with the diaphragm for coating.

In another embodiment, it further includes a second connecting group of rollers connecting the first connecting group of rollers and the reference roller, the second connecting group of rollers is used to adjust the transmission angle of the diaphragm and enlarge the wrapping angle of the diaphragm and the reference roller.

Specifically, the second connecting roller is composed of a passing roller 4 and a passing roller 5, which receives and adjusts the angle of the diaphragm transmitted by the passing roller 3. The passing roller 4 and the passing roller 5 are in contact with different sides of the diaphragm respectively, and the reference roller and the passing roller The contact surfaces between 5 and the diaphragm are also two different surfaces. After adjusting the angle of the passing roller 4, the contact angle between the diaphragm and the passing roller 5 is controlled within a range of less than or equal to 90°, and the diaphragm is transferred from the passing roller 5 to the reference roller. The angle adjustment of the passing roller 5 can increase the contact wrap angle between the diaphragm and the reference roller.

In another embodiment, a flattening roller is further provided between the reference roller and the first intermediate roller, and the flattening roller has a concave-convex surface for flattening the diaphragm so as to avoid wrinkles caused by the diaphragm being transported on the reference roller with a large wrap angle.

In one embodiment, a baking device is provided between the machine head and the discharge device, and the diaphragm passes through the second passing roller, that is, the passing roller 11. The passing roller 11 ensures the angle between the diaphragm and the roller while changing the direction, and enters the drying process. Oven for drying.

In this embodiment, after the dried diaphragm enters the discharge device, it passes through the third connected group of rollers composed of the roller 12 and the roller 13 in turn, and is adsorbed by the roller 14, wherein the roller 12 and the roller 13 By adjusting the angle of the diaphragm, the contact wrap angle between the diaphragm and the passing roller 14 is increased; the passing roller 14 controls the direct diaphragm tension between the passing roller 10 and the passing roller 14 through the connected fifth servo motor.

In another embodiment, after the diaphragm passes through the roller 14, the output angle of the diaphragm is adjusted through the roller 15 and output to the winding device. The roller 16 in the winding device changes the direction while ensuring the angle between the diaphragm and the roller, ensuring The wrap angle of the passing roller 17, the passing roller 17 is a flattening roller, which is used to ensure the smoothness of the diaphragm when it is rolled; the passing roller 18 ensures the angle between the diaphragm and the roller while changing the direction to ensure the angle of the winding roller; finally The coated separator is rotated and taken up by the take-up roller.

As shown in Figure 2, the present invention also proposes a control method for a lithium battery non-swing roll separator coating machine, comprising the following steps:

S1: Set the target tension value of the diaphragm, and calculate the preset torque according to the target tension value;

S2 collects the diaphragm tension value in real time, and calculates the tension deviation value at multiple moments based on the target tension value;

In one embodiment, collecting the diaphragm tension value in real time includes: collecting the diaphragm tension value between the unwinding device and the machine head; collecting the diaphragm tension value between the machine head and the discharge device; collecting the discharge device and the winding device The value of diaphragm tension between.

S3: Calculate the torque control increment according to the tension deviation values at multiple moments;

In one embodiment, the specific control method is as follows, the PLC calculates the deviation value E according to the target tension value SV set on the touch screen-the diaphragm tension value PV detected by the tension sensor, and then adopts the incremental PID algorithm to perform the calculation ΔU=KP* [E(n)-E(n-1)]+KI*E(n)+KD*[E(n)-2E(n-1)+E(n-2)]

Among them, ΔU is the unwinding servo torque control increment; KP is the proportional coefficient; KI is the integral coefficient; KD is the differential coefficient; E(n) is the current deviation value; E(n-1) is the deviation value calculated at the last moment ; E(n-2) is the deviation value calculated at the previous two moments.

The PLC program first calculates a servo torque preset torque according to the set tension SV parameter set on the touch screen, and then uses the preset torque + the calculation result ΔU of the above formula to output to the servo torque value. Since ΔU is a real-time adjusted variable, the control The current loop of the servo motor enables the tension of the unwinding mechanism to quickly reach the set value, and can be adjusted in real time to eliminate tension deviation during operation, so as to achieve the purpose of high-precision tension control. Among them, PV is displayed in real time on the touch screen; SV has an input box on the touch screen that allows users to adjust according to process requirements; KP has an input box on the touch screen that allows users to adjust according to process requirements; KI has an input box on the touch screen that allows users to adjust Adjust according to process requirements; KD has an input box on the touch screen to allow users to adjust according to process requirements.

In another embodiment, the steps also include:

S4: Set the friction parameter and obtain the diameter of the coil;

In one embodiment, the coil diameter includes the coil diameter of the unwinding roller, the coil diameter in the discharge pulling roller and/or the coil diameter of the take-up roller.

S5: Calculate the motor torque value according to the target tension value, friction parameter and coil diameter, and input it into the servo motor.

In another embodiment, each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for the related information, please refer to the description of the method part.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. The utility model provides a lithium cell does not have pendulum roller diaphragm coating machine which characterized in that includes: the device comprises a diaphragm, an unreeling device, a machine head, a discharging device, a reeling device, a data acquisition device and a control device;

the diaphragm is output by the unwinding device and sequentially passes through the machine head, the discharging device and the winding device;

the data acquisition device is arranged in the unwinding device, the machine head or the discharging device;

the control device is electrically connected with the data acquisition device.

2. The lithium battery swing-roller-free diaphragm coating machine as claimed in claim 1, wherein the unwinding device comprises an unwinding roller, and a first passing roller and a first connecting group roller which are arranged at the outlet end of the unwinding roller; the first roller passing is electrically connected with a first servo motor; the diaphragm is output to the machine head through the first roller and the first connecting group of rollers, and a contact angle between the diaphragm and the first roller and a contact angle between the diaphragm and the first connecting group of rollers is smaller than or equal to 90 degrees.

3. The lithium battery swinging-roller-free diaphragm coating machine as claimed in claim 2, wherein the data acquisition device comprises an ultrasonic sensor installed on the unwinding roller, and the ultrasonic sensor is electrically connected with the control device and used for detecting the diameter of the coiled material on the unwinding roller.

4. The lithium battery swinging-roller-free diaphragm coating machine as claimed in claim 2, wherein the machine head comprises a reference roller, a coating roller, a first middle roller and a second middle roller which are distributed on two sides of the coating roller, and a second passing roller which is arranged at the outlet of the machine head;

the diaphragm is conveyed by the reference roller and sequentially passes through the first middle roller, the coating roller, the second middle roller and the second roller, and contact angles between the diaphragm and the coating roller, the first middle roller, the second middle roller and the second roller are all less than or equal to 90 degrees.

5. The lithium battery pendulum-free roller separator coater according to claim 4, further comprising a second connection group roller connecting the first connection group roller and the reference roller, wherein the second connection group roller is configured to adjust a transmission angle of the separator and to enlarge a wrap angle of the separator and the reference roller.

6. The lithium battery swinging-roller-free diaphragm coating machine as claimed in claim 4, wherein a flattening roller is further arranged between the reference roller and the first intermediate roller, and the flattening roller is provided with a concave-convex surface for flattening the diaphragm.

7. A lithium battery swinging-roller-free diaphragm coating machine control method is characterized by comprising the following steps:

setting a target tension value of a diaphragm, and calculating a preset torque according to the target tension value;

acquiring a diaphragm tension value in real time, and calculating tension deviation values at multiple moments based on the target tension value;

and calculating the torque control increment according to the tension deviation values at the plurality of moments.

8. The lithium battery swing-roll-free membrane coater control method as claimed in claim 7, wherein said collecting membrane tension values in real time comprises:

acquiring a diaphragm tension value between an unreeling device and a machine head;

acquiring a diaphragm tension value between a machine head and a discharging device;

and acquiring a diaphragm tension value between the discharging device and the winding device.

9. The lithium battery swing-roll-free diaphragm coater control method as claimed in claim 7, wherein the steps further comprise:

setting friction parameters and obtaining the diameter of the coiled material;

and calculating a motor torque value according to the target tension value, the friction force parameter and the diameter of the coiled material, and inputting the motor torque value into a servo motor.

10. The lithium battery swing-roller-free diaphragm coating machine control method as claimed in claim 8, wherein the coil diameter comprises a coil diameter of an unwinding roller, a coil diameter in a discharging traction roller and/or a coil diameter of a winding roller.

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