KR102615777B1 - Machine direction orientation of stretching apparatus for manufacturing secondary battery separator - Google Patents

Abstract

The present invention relates to a longitudinal stretching device for manufacturing a secondary battery separator that performs longitudinal stretching of a separator film using a speed difference between rolls.
For this purpose, the longitudinal stretching device for manufacturing secondary battery separators has a lip roll connected to a cylinder placed on one side of the steel roll inside the chamber, and the lip roll preheats the separator film passing through the steel roll while pressing the separator film. A stretching portion is disposed inclined with respect to the vertical center line of the steel roll to press the separator film, and is disposed adjacent to the stretching portion. A lip roll is disposed on one side of the steel roll, so that the lip roll presses the separator film and presses the steel roll. It includes a heat section that fixes the temperature of the passing separator film and maintains the stretched state.

Description

Longitudinal stretching device for manufacturing secondary battery separators {MACHINE DIRECTION ORIENTATION OF STRETCHING APPARATUS FOR MANUFACTURING SECONDARY BATTERY SEPARATOR}

The present invention relates to a longitudinal stretching device for manufacturing secondary battery separators.

Generally, in the process of manufacturing a secondary battery separator, a dry separator method in which pores are formed by stretching an extruded PP film, or a wet separator method in which pores are formed using an extruded PE film solvent is applied.

In the case of the dry membrane method, it is difficult to form uniform pores because pores are formed by mechanical force.

In the case of the wet separator method, it is advantageous for electric devices that require constant output and long-term battery performance and has the advantages of excellent mechanical strength, formation of homogeneous pores, and process stability, but has the disadvantages of high process cost and low thermal stability.

Among these, the wet membrane production process involves extrusion of raw materials mixed with oil (wax) for pore formation, longitudinal stretching (MDO) process after casting, 1st transverse stretching (TDO, 1st) process, and oil (wax) production process. ) Extraction process, secondary transverse stretching (TDO, 2st) process.

At this time, when the pores have a uniform circular shape and uniform size, ions can pass smoothly, making it possible to produce a battery with high reliability. However, the separator production process generally involves longitudinal stretching, transverse stretching, extraction, and heat setting processes after casting. However, the separator film shrinks during the oil extraction process, and during this process, the pore shape of the film is formed into an oval shape. Accordingly, there is a problem in that passage of ions becomes difficult and the efficiency of ion electricity decreases.

Therefore, in order to secure the reliability of the separator, uniform stretching in the stretching process, process design that optimizes the stretching ratio, minimizing heat shrinkage and forming pores through heat setting, and securing mechanical strength are required.

However, existing separator manufacturing facilities consist of MD (longitudinal) stretching and TD (transverse) stretching facilities, and since non-linear stretching results occur due to stress during separator manufacturing, work to correct this is necessary, and the separator There is also a problem of quality deterioration.

Republic of Korea Patent Publication No. 10-1858566 (Title of invention: Secondary battery separator manufacturing method and manufacturing device, published on January 4, 2018) Republic of Korea Patent Publication No. 10-1561971 (Title of invention: Manufacturing system for separator film for secondary batteries, published on April 14, 2015)

The present invention was created in consideration of the above points, and is a secondary battery that uses the speed difference between rolls to stretch the separator film in the longitudinal direction and stably maintains the tension of the separator film to enable more efficient stretching. The purpose is to provide a longitudinal stretching device for manufacturing a separator.

According to a preferred embodiment for achieving the object of the present invention described above, the longitudinal stretching apparatus for manufacturing a secondary battery separator according to the present invention heats a separator film passing through a plurality of steel rolls inside a chamber, and attaches the separator film to one side of the steel rolls. A preheating unit in which a lip roll connected to the cylinder is disposed to preheat the separator film passing through the steel roll while the lip roll presses the separator film, the preheated separator film is stretched in the longitudinal direction while passing a plurality of steel rolls, and the lip roll is A stretching portion is disposed inclined with respect to the vertical center line of the steel roll to press the separator film, and is disposed adjacent to the stretching portion. A lip roll is disposed on one side of the steel roll, so that the lip roll presses the separator film and presses the steel roll. It may include a heat portion that fixes the temperature of the passing separator film and maintains the stretched state.

It may further include a movable cart installed at the top of the chamber to maintain and repair the equipment while moving along the upper frame.

A stabilization section is provided between the stretching portion and the heating portion to stabilize the stretched separator film.

The heating part is installed to be movable to one side, so that the stabilization section can be varied through movement of the heating part.

The preheating unit may include a scraper that contacts the steel roll to remove oil from the surface of the steel roll.

The scraper has a blade that directly contacts the surface of the steel roll to scrape oil, a moving shaft on which the blade is fixedly installed, and a moving shaft connected to the moving shaft to raise or lower the moving shaft to contact or separate the blade from the steel roll. It may include an actuating cylinder.

Tension detectors are installed at both ends of the lip roll of the stretched portion to detect the inclination of the lip roll.

The tension detector is connected to the control cylinder and operates the control cylinder through a signal from the pressure control valve to control the position of the lip roll.

As the lower base plate moves along the LM Guide, the heat portion may widen the gap with the elongated portion, thereby increasing the stabilization section.

A door frame may be installed on the lower part of the mobile bogie, and a door through which workers can enter the equipment may be installed on the door frame.

According to the longitudinal stretching device for manufacturing secondary battery separators according to the present invention, more efficient stretching of the separator film is possible by performing longitudinal stretching of the separator film using the speed difference between rolls, and the tension of the separator film undergoing the stretching process is reduced. By maintaining stability, the quality of the produced separator can be improved.

In addition, in order to stabilize the separator film after stretching, a stabilization section of the separator film can be provided to induce natural shrinkage of the separator film, thus stabilizing the separator manufacturing process.

In addition, workers can safely enter the longitudinal stretching device to maintain and repair the device, thereby protecting workers and improving workability.

Figure 1 is a diagram showing a longitudinal stretching apparatus for manufacturing a secondary battery separator according to an embodiment of the present invention.
Figure 2 is a diagram showing an oil scraper of a preheating unit according to an embodiment of the present invention.
Figure 3 is a diagram showing the installation state of the longitudinal stretching device lip roll according to an embodiment of the present invention.
Figure 4 is a diagram showing a tension detector of a longitudinal stretching device roll according to an embodiment of the present invention.
Figure 5 is a diagram showing a heat opening of a longitudinal stretching device according to an embodiment of the present invention.
Figure 6 is a diagram showing a movable bogie of a longitudinal stretching device according to an embodiment of the present invention.

Hereinafter, an embodiment of a longitudinal stretching apparatus for manufacturing a secondary battery separator according to the present invention will be described with reference to the attached drawings. At this time, the present invention is not limited or limited by the examples. Additionally, when describing the present invention, detailed descriptions of well-known functions or configurations may be omitted to make the gist of the present invention clear.

Figure 1 is a diagram showing a longitudinal stretching apparatus for manufacturing a secondary battery separator according to an embodiment of the present invention. Figure 2 is a diagram showing an oil scraper of a preheating unit according to an embodiment of the present invention.

Referring to FIGS. 1 and 2, the longitudinal stretching device 1 for manufacturing a secondary battery separator according to the present invention includes a preheating unit 10, a stretching unit 20, a heating unit 30, and a movable cart 40. And, the separator film (F) passing through the stretching device (1) is stretched in the longitudinal direction.

In this embodiment, the preheating unit 10 of the stretching device 1 heats the separator film F passing through the plurality of steel rolls 11 inside the chamber 2 and one side of the steel roll 11. This is a section in which the lip roll 12 connected to the cylinder 12a is disposed so that the lip roll 12 presses the separator film F and preheats the separator film F passing through the steel roll 11.

In addition, the stretching portion 20 stretches the preheated separator film F in the longitudinal direction as it passes through a plurality of steel rolls 21, and the lip roll 22 is aligned with the vertical center line of the steel roll 21. This is a section that is arranged at an angle and presses the separator film (F).

In addition, the heat portion 30 is disposed adjacent to the stretching portion 20, and a lip roll 32 is disposed on one side of the steel roll 31, so that the lip roll 32 presses the separator film F This is a section where the temperature of the separator film (F) passing through (31) is fixed and maintained in the stretched state.

In addition, the movable cart 40 installed on the upper part of the chamber 2 of the stretching device 1 maintains and repairs the equipment while moving along the upper frame 2a, so that the operator can use the movable cart 40. After entering the inside of the chamber (2) while moving the upper part of the stretching device (1) by riding on it, necessary actions can be taken for the stretching device (1).

That is, the stretching device 1 is a device that stretches the separator film (F) in the longitudinal direction using the speed difference between rolls. As the separator film (F) is stretched in the longitudinal direction, the separator film (F) becomes thinner and its width increases. This becomes narrow.

The stretching device (1) has lip rolls (12, 22, 32) in contact with the steel rolls (11, 21, 31) in an inclined state to stabilize the separator film (F) passing through the steel rolls (11, 21, 31). By pressing, the separator film (F) can have optimal tension, which enables efficient stretching of the separator film (F).

In this embodiment, a stabilization section (SZ) is provided between the stretching unit 20 and the heating unit 30 of the stretching device 1 to stabilize the stretched separator film F, and the heating unit (30) is installed to be movable to one side, so that the stabilization section (SZ) can be varied by moving the opening portion (30).

In addition, the preheating unit 10 of the stretching device 1 includes a scraper 13 that contacts the steel roll 11 to remove oil from the surface of the steel roll 11, and the scraper 13 is A blade 13a that directly contacts the surface of the steel roll 11 to scrape oil, a moving shaft 13b on which the blade 13a is fixed, and a moving shaft 13b connected to the moving shaft 13b. It includes an operating cylinder 13c that raises or lowers the blade 13a to contact or separate from the steel roll 11.

The amount of oil removed from the steel roll 11 can be adjusted by adjusting the position of the blade 13a in contact with the steel roll 11. When the blade 13a is brought into close contact with the steel roll 11, a greater amount of oil can be removed, and when the blade 13a is brought into contact with the steel roll 11 with appropriate force, an appropriate amount of oil can be removed. You can.

That is, since the separator film (F) is input in an unformed state in the process of being input into the stretching device (1), the oil on the surface of the separator film (F) is excessively applied to the steel roll (11), and this The scraper 13 is installed adjacent to the steel roll 11 to remove oil.

In addition, the scraper is installed on the three steel rolls (11) disposed at the initial position where the separator film (F) is input into the stretching device (1) to preferentially remove the oil applied to the three steel rolls (11). Through this, the quality of the produced separator film (F) can be improved by maintaining an appropriate amount of oil applied to the separator film (F) that passes through the remaining steel rolls (11, 21, and 31).

Figure 3 is a diagram showing the installation state of the longitudinal stretching device lip roll according to an embodiment of the present invention. Figure 4 is a diagram showing a tension detector of a longitudinal stretching device roll according to an embodiment of the present invention.

Referring to FIGS. 3 and 4, the stretching portion 20 of the stretching device 1 has a lip roll 22 disposed at an angle based on the vertical center line of the steel roll 21 to press the separator film F. In other words, the lip roll 22 of the stretching portion 20 is positioned at a point of 35° to 45° relative to the vertical center line of the steel roll 21 so that the separator film F first meets the steel roll 21. It has an angle (θ) range.

The lip roll 22 is preferably disposed inclined at an angle of 40° with respect to the vertical center line of the steel roll 21.

Accordingly, since the lip roll 22 presses the separator film (F) evenly, stable stretching of the separator film (F) is possible, and fracture of the separator film (F) that may occur during the stretching process of the separator film (F) is possible. can be prevented in advance.

In addition, tension detectors 23 are installed at both ends of the lip roll 22 of the stretching portion 20 to detect the inclination of the lip roll 22, and the tension detector 23 includes an adjustment cylinder 22a and The position of the lip roll 22 can be adjusted by operating the control cylinder 22a through a signal from the pressure control valve 24.

That is, during the stretching process of the separator film (F), the lip roll (22) pressing the separator film (F) may be tilted to one side, so the tension detector (23) is used to keep the lip roll (22) horizontal. 22), the tilt is detected.

The pressure control valve 24 is operated by a signal from the tension detector 23 that detects the inclination of the lip roll 22, and the control cylinder 22a is operated by the operation of the pressure control valve 24 to tilt. The lip roll 22 is maintained horizontally, and through this, the lip roll 22 can press the separator film F evenly.

Figure 5 is a diagram showing a heat opening of a longitudinal stretching device according to an embodiment of the present invention.

Referring to FIG. 5, the opening portion 30 of the stretching device 1 widens the gap between the lower base plate 33 and the stretching portion 20 as the lower base plate 33 moves along the LM guide 34 to form a separator film (F). ) can increase the stabilization zone (SZ).

The base plate 33 is connected to the moving means 35 and can be moved along the LM guide 34 by the operation of the moving means 35. Since the heat section 30 can be moved by approximately 550 mm through the moving means 35, the stabilization section (SZ) of the separator film (F) can be further secured by this moving distance.

The stabilization section (SZ) provides time for the separator film (F) to naturally shrink after longitudinal stretching (MDO) of the separator film (F) and before transverse stretching (TDO).

Figure 6 is a diagram showing a movable bogie of a longitudinal stretching device according to an embodiment of the present invention.

Referring to FIG. 6, the movable cart 40 of the stretching device 1 is installed to move along a rail 41 installed on the upper frame 2a of the chamber 2, and the rail 41 and A moving handle 42 is connected in the vertical direction, and the mobile bogie 40 moves by manipulating the moving handle 42.

In addition, a door frame 40b is installed on the lower part of the cart frame 40a of the mobile cart 40, and a door 43 through which workers can enter the equipment is installed on the door frame 40b.

After moving the mobile cart 40 to a point where maintenance and repair of the stretching device 1 is required, the operator opens the door 43 of the mobile cart 40 and the chamber of the stretching device 1 ( 2) Enter inside to carry out maintenance and repair work.

Therefore, the longitudinal stretching device 1 for manufacturing a secondary battery separator enables more efficient stretching of the separator film (F) by using the speed difference between rolls to stretch the separator film (F) in the longitudinal direction, and the stretching process is The quality of the produced separator can be improved by stably maintaining the tension of the separated separator film (F).

In addition, in order to stabilize the separator film (F) after stretching, a stabilization section (SZ) of the separator film (F) is provided to induce natural shrinkage of the separator film (F), thereby stabilizing the separator manufacturing process.

In addition, since workers can safely enter the stretching device 1 to maintain and repair the device, workability can be improved while protecting workers.

Although the present invention has been shown and described in connection with preferred embodiments for illustrating the principles of the invention, the invention is not limited to the construction and operation as shown and described. Rather, those skilled in the art will understand that numerous changes and modifications can be made to the present invention without departing from the spirit and scope of the appended claims.

1: Stretching device 2: Chamber
2a: upper frame 10: preheating unit
11: steel roll 12: lip roll
12a: cylinder 13: scraper
13a: blade 13b: moving axis
13c: operating cylinder 20: stretching portion
21: steel roll 22: lip roll
22a: Adjusting cylinder 23: Tension detector
24: Pressure control valve 30: Opening part
31: steel roll 32: lip roll
33: Base board 34: Elm guide
35: means of transportation 40: mobile bogie
40a: Bogie frame 40b: Door frame
41: Rail 42: Moving handle
43: door
F: Separator film
SZ: stabilization zone

Claims (10)

A preheating unit that heats the separator film passing through a plurality of steel rolls inside the chamber and preheats the separator film passing through the steel rolls by placing a lip roll connected to a cylinder on one side of the steel roll so that the lip roll presses the separator film;
A stretching unit in which the preheated separator film is stretched in the longitudinal direction as it passes through a plurality of steel rolls, and lip rolls are arranged at an angle with respect to the vertical center line of the steel rolls to press the separator film; and
A heating unit disposed adjacent to the stretching unit and having a lip roll disposed on one side of the steel roll so that the lip roll presses the separator film and fixes the temperature of the separator film passing through the steel roll to maintain the stretched state; Including,
The lip roll of the stretching portion has an angle (θ) ranging from 35° to 45° with respect to the vertical center line of the steel roll so that the separator film (F) is disposed at the point where it first meets the steel roll,
A stabilization section is provided between the stretching portion and the heating portion to stabilize the stretched separator film,
The heat section is installed to be movable to one side and changes the stabilization section through movement of the heat section,
As the lower base plate moves along the LM guide, the heat portion widens the gap with the elongated portion, thereby increasing the stabilization section,
The base plate is connected to a moving means and moves along the LM guide by the operation of the moving means,
The stabilization section is a longitudinal stretching device for manufacturing a secondary battery separator, characterized in that the separator film (F) is given time to naturally shrink after longitudinal stretching of the separator film (F) and before transverse stretching. According to claim 1,
A longitudinal stretching device for manufacturing a secondary battery separator further comprising a movable cart installed at the top of the chamber to maintain and repair the equipment while moving along the upper frame. delete delete According to claim 1,
A longitudinal stretching device for manufacturing a secondary battery separator, wherein the preheating unit includes a scraper that contacts the steel roll to remove oil from the surface of the steel roll. According to claim 5,
The scraper has a blade that directly contacts the surface of the steel roll to scrape oil, a moving shaft on which the blade is fixedly installed, and a moving shaft connected to the moving shaft to raise or lower the moving shaft to contact or separate the blade from the steel roll. A longitudinal stretching device for manufacturing a secondary battery separator including an operating cylinder. According to claim 1,
A longitudinal stretching device for manufacturing a secondary battery separator, wherein tension detectors are installed at both ends of the lip roll of the stretching portion to detect tilt of the lip roll. According to claim 7,
The tension detector is connected to a control cylinder and operates the control cylinder through a signal from a pressure control valve to control the position of the lip roll. delete According to claim 2,
A longitudinal stretching device for manufacturing a secondary battery separator, characterized in that a door frame is installed on the lower part of the mobile bogie, and a door through which an operator can enter the equipment is installed on the door frame.

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