JPH0963576A - Drying device and drying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance drying efficiency by suppressing the swing of an electrode sheet. SOLUTION: Air blow nozzles 21 for blowing hot air onto both sides of an electrode sheet 33 for a battery to both sides of which an electrode mix is applied are arranged. A pair of upper and lower slit-shaped blow ports 65 extended in the width direction of the electrode sheet 33 is arranged in the edge part 63 of each side of the air blow nozzle 21. The electrode mix is dried with hot air blown from a pair of upper and lower blow ports 65 on both sides, the region between the electrode sheet 33 and the edge part 63 is made high pressure to form a high pressure room P, and the electrode sheet 33 is supported with the right and left high pressure rooms P, and thereby the swing of the electrode sheet 33 is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible strip-shaped sheet having both surfaces coated with a coating solution, which is conveyed vertically.
The present invention relates to a drying device and a drying method for drying a coating liquid in the process of conveying in the vertical direction.

[0002]

2. Description of the Related Art As a flexible strip-shaped sheet coated with a coating liquid on both sides, for example, there is an electrode sheet for a battery coated with an electrode mixture on both sides. Here, an electrode sheet for a nickel-hydrogen battery is used. Take for example. The nickel-hydrogen battery uses a polyester fibrous material plated with nickel as a base material on the anode side, while using a stainless steel sheet as a base material on the cathode side, and a nickel paste and water on the anode side. On the cathode side, the above electrode mixture is applied, and after the electrode mixture including the hydrogen storage alloy paste and water is applied, the applied electrode mixture is dried.

FIG. 7 schematically shows the coating and drying of the electrode mixture on the electrode sheet. The coating machine 1 is arranged on the lower side and the dryer 3 is arranged on the upper side, and the electrode sheet 5 is It is conveyed upward between the lower roller 7 and the upper roller 9. The coating machine 1 includes an electrode mixture 13 in a container 11.
Are filled, and the electrode sheet 5 moves upward from below with respect to the container 11, whereby the electrode mixture 13 is applied to both surfaces, and the blade 15 disposed above the liquid surface of the electrode mixture 13 is filled. Will scrape off the excess electrode mixture 13,
A uniform coating surface is secured. The dryer 3 is provided with air blowing nozzles 19 arranged on both sides of the coating surface of the electrode sheet 5 in a drying furnace 17, and blows hot air to the coating surface of the electrode sheet 5 moving upward. dry.

Each of the air blowing nozzles 19 has only one air outlet, and, for example, the air blowing nozzles 19 on both sides of the electrode sheet 5 are arranged so as to face each other, or hot air blown onto the electrode sheet 5. In order to form a parallel flow, there is a structure in which the air flow blown out from the air blowing nozzle 19 is arranged so as to be inclined upward.

[0005]

By the way, the electrode sheet 5 does not have a pressing portion between the coating machine 1 and the upper roller 9, and the height of the drying oven 17 is the same as the above-mentioned nickel-hydrogen. The anode base material of the battery is about 6 m, and the cathode base material is about 8 m, which is extremely long and therefore easily shakes in the drying furnace 17. When the electrode sheet 5 shakes greatly,
There is a problem that not only the coating surface is adversely affected, for example, the coating film thickness in the drying furnace 17 is changed, but also the coating process in the coating machine 1 is adversely affected, and a uniform coating surface cannot be obtained. .

Therefore, conventionally, the air blowing nozzle 19 is largely separated from the electrode sheet 5, or the air blowing nozzle 19 is used.
Measures such as slowing down the flow velocity of the air blown out from the chamber were taken, and the drying efficiency was not sufficient.

In order to deal with this, it is conceivable to set the temperature in the drying oven 17 high or to increase the height of the drying oven 17 in order to increase the transport distance in the drying oven 17. However, in the case of the former, it is necessary to take measures such as increasing the output of the electric heater, which leads to an increase in cost. On the other hand, in the case of the latter, not only the size of the dryer is increased, but also the electrode sheet 5 Since the transport distance is long, there is a fatal drawback that it becomes easier to shake.

Therefore, an object of the present invention is to suppress the shaking of the strip-shaped sheet in the drying furnace and improve the drying efficiency.

[0009]

In order to achieve the above-mentioned object, the present invention is, firstly, that a flexible strip-shaped sheet having a coating liquid applied on both sides is conveyed in the vertical direction, and is moved in the vertical direction. In a drying device for drying the coating liquid in the conveying process of, the air-blowing nozzles are arranged to face each other at a position apart from the belt-shaped sheet by a predetermined distance by sandwiching the belt-shaped sheet coated with the coating liquid. Each air outlet nozzle
It is configured to have an end face portion facing the strip-shaped sheet, and slit-shaped outlets provided on both sides of the end face portion in the conveyance direction of the strip-shaped sheet and extending in the width direction of the strip-shaped sheet.

Secondly, in the first structure, the strip-shaped sheet is an electrode sheet for a battery in which an electrode mixture is applied on both sides.

Thirdly, in the first configuration or the second configuration, the air blowing nozzle is provided so as to be movable in a direction in which the air blowing nozzle approaches and separates from the belt-shaped sheet.

Fourthly, a strip-shaped battery electrode sheet having both sides coated with an electrode mixture is conveyed in the vertical direction, and in the drying process in which the coating liquid is dried during the conveyance process in the vertical direction, the electrode sheet is used. With respect to the end face portion where the slit-shaped blowout port extended in the width direction of the electrode sheet is arranged so as to face the electrode sheet, the air blowing nozzles provided on both sides in the transport direction of the electrode sheet are sandwiched between the electrode sheets. Arranged opposite to each other at a position separated from the mixture application surface by a predetermined distance, and by the air blown from the two outlets of the air outlet nozzle, the end face portion between the two outlets and the electrode sheet This is a method in which a high-pressure chamber is formed between them and the coating liquid is dried while the electrode sheets are held down from both sides.

According to the above structure, the air blown from the two outlets of the air blowing nozzle is blown onto the strip-shaped sheet and then flows toward the space between the two outlets, whereby the strip-shaped sheet and the end surface are The high pressure chamber is formed by increasing the pressure in the region between the high pressure chamber and the air discharge nozzle.
Since the strip-shaped sheets are arranged so as to face each other with the strip-shaped sheets sandwiched therebetween, they are formed on both sides of the strip-shaped sheet, and the high-pressure chambers on both sides press the strip-shaped sheet to suppress shaking.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view around an air blowing nozzle 21 in a drying apparatus showing an embodiment of the present invention, FIG.
1 is a front view of the air blowing nozzle 21 of FIG. 1, FIG. 3 is an internal structure diagram centering on a dryer 23 having a plurality of air blowing nozzles 21 provided therein, and FIG. 4 is a left side surface of only the dryer 23 in FIG. FIG. 5 is a right side sectional view of only the dryer 23 in FIG. The dryer 23 is used as an electrode sheet for a hydrogen electrode on the cathode side of a nickel-hydrogen battery.

In FIG. 3, a coating machine equipped with a blade 27 and a container 27 filled with an electrode mixture 25 as a coating solution is provided in the lower part of the dryer 23 as in the conventional example shown in FIG. 31, the electrode sheet 33 as a flexible strip-shaped sheet is applied with the electrode mixture on both surfaces by passing through the coating machine 31 via the inlet roller 35. Coating machine 31
The electrode sheet 33 to which the electrode mixture is applied enters into the drying oven 37 upward and is turned around by the turn roller 39 provided at the upper end of the drying oven 37. The direction-changed electrode sheet 33 advances downward and is dried in the drying oven 37.
It re-enters the inside and moves to the outside via the outlet roller 41 provided at the bottom of the dryer 23.

Air blowing nozzles 21 shown in detail in FIG. 1 are provided on the left and right sides in FIG. 3 where the electrode sheet 25 moves upward in the drying oven 37. A plurality of air blowing nozzles 21 are provided along the upward movement path of the electrode sheet 33 over substantially the entire area from the lower end surface to the upper end surface of the drying oven 37. The plurality of air blowing nozzles 21
Are divided into three groups along the movement path of the electrode sheet 33, and the air blowing nozzles 21 of each of the three groups are
It is housed in a nozzle unit 43 as shown in FIG.

In the nozzle unit 43, an electric heater 49 is provided in an inlet duct 47 on the upstream side of the blower 45, and an outlet duct 51 on the downstream side of the blower 45 is bifurcated. The bifurcated outlet duct 51 communicates with each of the left and right air blowing nozzles 21 via a guide passage 53. The inlet duct 47 is opened to an inlet space 59 that is partitioned from the furnace interior space 57 by the filter 55 in FIG. 4, and is heated by the electric heater 49 to be blown out by the air blowing nozzle 21.
The air blown out from the diffuser diffuses into the furnace space 57 and enters the inlet duct 47 from the inlet space 59 through the filter 55. In this way, the air sent from the blower 45 circulates through the filter 55, but in order to prevent water in the electrode mixture applied to the electrode sheet 33 from evaporating and forming dew condensation, An exhaust port that communicates with the outside and is forcibly exhausted by a fan or the like is provided in the furnace space 57, and an air inlet port for introducing an air amount commensurate with the air exhausted from the exhaust port is provided in the inlet space 59. It is provided in communication.

As shown in FIGS. 1 and 2, the air blowing nozzle 21 has a slit shape extending in the width direction of the electrode sheet 33 on both sides of the end face portion 63 at the tip of the nozzle body 61 in the conveying direction of the electrode sheet 33. A pair of air outlets 65 are provided. The nozzle body 61 is a cylindrical body 61a.
And a nozzle end portion 61b that is inserted into the front end side opening and forms a pair of upper and lower outlets 65 with the main body 61a. The nozzle end portion 61b is a partition wall 61c formed in the main body 61a. The rear end face is fixed. A vent hole 61d is formed in the partition wall 61c, and the main body 61 on the upstream side thereof is further formed.
A rectifying plate 67 having a large number of small holes is provided in a.

Regarding the two air blowing nozzles 21 facing each other on both sides of the electrode sheet 33, the electrode sheet 33
The distances from the coating surface are equal to each other, and the blowing speeds are also equal to each other.

In the area where the electrode sheet 33 moves downward in the drying oven 37, a vertical duct 69 is provided to cover the periphery of the electrode sheet 33 over the entire length in the moving direction of the electrode sheet 33. In this vertical duct 69,
The outlet duct 73 on the downstream side of the blower 71 is communicatively connected via a communication duct 75 at the central portion and the lower portion in the vertical direction in FIG. 5, and an electric heater 79 is provided on an inlet duct 77 on the upstream side of the blower 71. There is.

The inlet duct 77 is opened to an inlet space 85 which is partitioned from the furnace inner space 83 by a filter 81, and the air heated by the electric heater 79, sent out from the blower 71, and flown into the vertical duct 69 flows. From the communication holes (not shown) formed in the vertical duct 69, the gas flows into the furnace internal space 83, and enters the inlet duct 77 from the inlet space 85 through the filter 81. Although not shown in the figure, the furnace space 83 is also provided with a forced exhaust port communicating with the outside and an air inlet port is provided in the inlet space 85, respectively. It is possible to prevent water from evaporating and forming condensation.

In the drying device constructed as described above, the electrode sheet 33 having the electrode mixture applied on both sides is shown in FIG.
In the process of being conveyed from the lower part to the upper part in the inside, the air heated by the electric heater 49 passes from the blower 45 through the outlet duct 51 and the guide passage 53, and as the hot air H, as shown in FIG. Is supplied to. The hot air H supplied to the air blowing nozzle 21 is rectified by the rectifying plate 67, then passes through the ventilation hole 61d, is blown to the outside from the blowout port 65, is blown to the electrode sheet 33, and is applied to the electrode mixture. To dry.

The hot air blown onto the electrode sheet 33 is
Some of them flow to the outside of the air blowing nozzle 21, and some of them flow to the inside of the air blowing nozzle 21 along the coating surface of the electrode sheet 33. Due to the flowing hot air, the space between the electrode sheet 33 and the end surface portion 63 has a high pressure and forms the high pressure chamber P.

Since the high pressure chamber P is formed on both sides of the electrode sheet 33 by the pair of left and right air blowing nozzles 21,
The high pressure air on both sides presses the electrode sheet 33 and prevents the electrode sheet 33 from shaking. According to this configuration, the blowing speed from the air blowing nozzle 21 can be up to 30 m / sec, but as an actual usage example, it is about 15 m / sec depending on the capacity of the device before and after the drying device, Conventional 5m / s
Compared to ec, it is possible to increase the speed by about 3 times while preventing shaking, which can contribute to the improvement of drying efficiency.

Since the swinging of the electrode sheet 33 is suppressed, the transport speed of the electrode sheet 33 can be increased several times faster than in the conventional case, drying can be performed in a short time, and the drying efficiency is improved. Further, since the drying efficiency is improved, the height of the drying oven 37 can be reduced, the dryer 23 can be downsized, and the size of the height can be reduced, so that the vibration of the electrode sheet 33 can be further reduced. You can

Further, by suppressing the shaking of the electrode sheet 33, the unevenness of the coating film thickness due to the shaking in the drying oven 37 can be prevented, and the uniform coating can be achieved even in the coating operation by the coating machine 31. The surface will be obtained.

Further, the left and right air blowing nozzles 21 are configured to be movable in a direction toward and away from the electrode sheet 33 while ensuring a uniform distance from the electrode sheet 33 on the left and right sides, so that the blown air flow velocity can be increased. It becomes possible to respond to changes in.

In the above embodiment, the air blowing nozzle 2
1 shows an example in which the dryer is used as an electrode sheet for a hydrogen electrode on the cathode side in a nickel-hydrogen battery, an electrode sheet for a nickel electrode on the anode side, an electrode sheet for another battery, Alternatively, the same effect can be obtained by applying the present invention to not only the electrode sheet but also a dryer used for a flexible strip-shaped sheet.

[0030]

As described above, according to the present invention, the air blown from the two outlets of the air blowing nozzle increases the pressure in the region between the strip-shaped sheet and the end face portion, and the high pressure chamber. The air-blowing nozzles are formed on both sides of the strip-shaped sheet because the air blowing nozzles are arranged to face each other with the strip-shaped sheet sandwiched therebetween. Can be suppressed, which can contribute to the improvement of drying efficiency.

[Brief description of drawings]

FIG. 1 is a sectional view around an air blowing nozzle showing an embodiment of the present invention.

FIG. 2 is a front view of the air blowing nozzle of FIG.

FIG. 3 is an internal structural diagram of a dryer having a plurality of air blowing nozzles shown in FIG.

FIG. 4 is a left side sectional view of a main part of FIG.

5 is a right side sectional view of the main part of FIG.

6 is a perspective view of a nozzle unit including the air blowing nozzle of FIG. 1. FIG.

FIG. 7 is an explanatory view schematically showing application and drying of an electrode mixture on an electrode sheet in a conventional example.

[Explanation of symbols]

 21 Air Blow Nozzle 33 Electrode Sheet (Band-shaped Sheet) 63 End Face 65 Blowout P P High Pressure Chamber

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiko Kusato 2068 Ooka, Numazu City, Shizuoka Prefecture Toshiba Machine Co., Ltd. Numazu Office

Claims (4)

[Claims] 1. A drying device, in which a flexible strip-shaped sheet having a coating solution applied on both sides is conveyed in an up-down direction, and the coating solution is dried in the process of conveying in the up-down direction,
Air-blowing nozzles are arranged facing each other at a predetermined distance from the band-shaped sheet with the band-shaped sheet coated with the coating liquid sandwiched therebetween, and each air-blowing nozzle has an end face portion facing the band-shaped sheet. And a slit-shaped outlet provided on both sides of the end face in the conveyance direction of the belt-like sheet and extending in the width direction of the belt-like sheet. 2. The drying device according to claim 1, wherein the strip-shaped sheet is an electrode sheet for a battery whose both surfaces are coated with an electrode mixture. 3. The drying device according to claim 1, wherein the air blowing nozzle is provided so as to be movable in a direction of approaching and separating from the belt-shaped sheet. 4. The width of the electrode sheet in a drying method in which a strip-shaped battery electrode sheet coated with an electrode mixture on both sides is transported in the vertical direction and the coating liquid is dried in the process of transporting in the vertical direction. The slit-shaped air outlets extending in the direction of the electrode sheet are provided on both sides of the electrode sheet in the conveying direction with respect to the end surface portion which is arranged to face the electrode sheet, and the electrode sheet is sandwiched between the air blowing nozzles. The air is blown from the two outlets of the air-blowing nozzle, and the air is blown from the two outlets of the air-blowing nozzle between the end face portion and the electrode sheet between the two outlets. A drying method characterized in that a high-pressure chamber is formed and the coating liquid is dried while pressing the electrode sheets from both sides.