JPH0955205A - Slurry applying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the slurry applying thickness of the central part and the end part of a substrate uniform by letting slurry scrapped off with a slit flow down without joining to slurry introduced into the slit together with the substrate. SOLUTION: A porous substrate 4 is introduced from the bottom of a slurry bath 8 in which slurry 8 is filled to apply slurry 3a to both surfaces of the substrate 4. The substrate 4 is introduced into a pair of slits 2 closely faced each other, and the applying thickness of the slurry 3 is adjusted with an applying thickness adjusting part 5 formed between the vertical surfaces 7 of the slit 2. The excess slurry 3b scraped off in the applying thickness adjusting part 5 is circulated along a circulating part 6 having an inclined angle of 30-50 deg. to the width direction of the substrate 4, then flows in the slurry bath 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slurry coating device, and more particularly to a slurry coating device capable of making the slurry coating thickness uniform at the central portion and the end portion of a substrate.

[0002]

2. Description of the Related Art Generally, an electrode plate used in an alkaline storage battery or the like is manufactured by coating a slurry of electrode material powder on a substrate having a large number of holes such as sponge-like nickel or punching metal. In the slurry application step, if the thickness of the slurry applied to the substrate is not uniform, the characteristics of the internal resistance and capacity of the battery may vary. Conventionally, in order to uniformly adjust the slurry coating thickness, for example, a slit as disclosed in JP-A-3-43958 has been used.

As shown in FIG. 7, the conventional slit 50 comprises a pair of slit members 51, 51. Each slit member 51 has a substantially trapezoidal cross section and is formed to extend in the longitudinal direction. The slit 50 is a pair of slit members 5
1, a long substrate 53, in which the slurry 52 is applied, is introduced so that the first substrate 51 and the first substrate 51 face each other in close proximity to each other.
3 has a coating thickness adjusting section 54 for adjusting the coating thickness of the slurry 52 applied to the No. 3 and a circulation section 55 for circulating the slurry 52 scraped off by the coating thickness adjusting section 54. The width of the coating thickness adjusting portion 54 is configured so that it can be adjusted to obtain a desired slurry coating thickness. The circulation portion 55 is formed of an inclined surface inclined at a predetermined angle (30 ° to 75 °) with respect to the longitudinal direction of the substrate, and prevents the slurry 52 from staying on the lower surface of the slit 50. The substrate 53 is formed in a long strip shape and is vertically pulled up by a driving device and a winding roll (not shown).

As shown in FIG. 8, the substrate 53 is introduced from the bottom of a slurry tank 56 containing the slurry 52, passes through the slurry tank 56, and deposits the slurry 52 on both surfaces. Next, the substrate 53 is the coating thickness adjusting portion 5 of the slit 50.
A desired slurry coating thickness is obtained through 4. Slit 50
The excess slurry 52b scraped off at the entrance of the slurry coating thickness adjusting unit 54 is circulated along the circulation unit 55,
Furthermore, due to its own weight, the slurry 52 flowing from bottom to top
It flows down to the slurry tank 56 along the surface of a.

[0005]

Conventional slit 50
Since the circulation portion 55 of the slit is horizontal with respect to the width direction of the substrate 53, the slurry 52b scraped off by the slit 50 tends to gather in the central portion of the slit. Therefore, a part of the slurry 52a that tries to rise in contact with the substrate 53 is withdrawn along with the scraped slurry 52b, so that the slurry coating thickness at the center of the substrate 53 is smaller than the slurry coating thickness at the end. Becomes thinner,
There is a problem that a uniform slurry coating thickness cannot be obtained.

The present invention has been made in view of the above problems, and when adjusting the coating thickness of the slurry applied to the substrate, it is necessary to make the slurry coating thickness of the central portion and the end portion of the substrate uniform. It is an object of the present invention to provide a slurry coating device capable of performing the above.

[0007]

In order to solve the above-mentioned problems, a slurry coating apparatus according to a first aspect of the present invention includes a slurry tank, a substrate which moves upward in the slurry tank, and a substrate for the substrate. In a slurry coating device having a slit for adjusting the thickness of the excessively attached slurry, the slit is a slurry scraped by the slit,
It is characterized in that it is inclined at a predetermined angle with respect to the width direction of the substrate so that it will flow down without flowing together with the slurry introduced into the slit together with the substrate.

Further, in the slurry coating apparatus according to the second aspect of the present invention, the slurry coated on the long substrate is scraped off to adjust the coating thickness to a predetermined value, and the slit is scraped off. The present invention is characterized in that a slurry receiver for accumulating the slurry and a suction pump for sucking the slurry accumulated in the slurry receiver are provided.

[0009]

According to the slurry coating apparatus of the first aspect of the present invention, since the slit is inclined at a predetermined angle with respect to the width direction of the substrate, the slurry scraped by the slit is
It flows down without joining the slurry introduced into the slurry together with the substrate.

According to the slurry applying apparatus of the second aspect of the present invention, the slurry scraped off by the slit is stored in the slurry receiver, and then the slurry stored in the slurry receiver is sucked by the suction pump. . Therefore, the slurry scraped off by the slit does not merge with the slurry introduced into the slit together with the substrate.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1A is a perspective view showing a slurry coating apparatus according to the present invention.

The slurry coating apparatus 1 of the present invention has a pair of slits 2 which are arranged close to each other and face each other. The slit 2 introduces the substrate 4 coated with the slurry 3 and adjusts the coating thickness of the slurry 3 coated on the substrate 4, and the slurry scraped by the coating thickness adjusting unit 5. It has a circulation part 6 that causes 3 to flow and falls.
The coating thickness adjusting portion 5 is formed between the vertical surfaces 7 of the respective slits 2, and the width of each vertical surface 7 can be adjusted so as to obtain a desired slurry coating thickness. The circulation unit 6 is
The substrate 4 has an inclined surface that is inclined at a predetermined angle with respect to the longitudinal direction, that is, the vertical direction, and is also inclined at a predetermined angle with respect to the width direction of the substrate 4, that is, the horizontal direction. The inclination angle of the circulation portion 6 with respect to the width direction of the substrate 4 varies depending on various conditions such as the viscosity and type of the slurry 3, but is usually preferably in the range of 30 ° to 50 °.

The substrate 4 is a porous base material (sponge-like nickel) used for an electrode plate of an alkaline storage battery or the like, and is formed in a long strip shape. The substrate 4 is pulled up in the vertical direction by a driving device and a winding roll (not shown).

As shown in FIG. 1B, the substrate 4 is introduced from the bottom of a slurry tank 8 containing the slurry 3 and passes through the slurry tank 8 to adhere the slurry 3a to both surfaces. Next, the substrate 4 is introduced into the slit 2 and passes through the coating thickness adjusting section 5 to obtain a predetermined slurry coating thickness. The extra slurry 3b scraped at the entrance of the coating thickness adjusting unit 5 of the slit 2 is swirled along the swirling unit 6. At that time, since the circulation portion 6 is formed to be inclined at a predetermined angle with respect to the widthwise direction of the substrate 4, the slurry 3b scraped by the coating thickness adjusting portion 5 is stored in the coating thickness adjusting portion 5 together with the substrate 4. It flows down into the slurry tank 8 without joining the introduced slurry 3a. According to the slurry coating apparatus 1 of the present invention, the substrate 4
The slurry coating thickness at the central portion of the substrate does not become thinner than the slurry coating thickness at the end portion, and the slurry coating thickness at the central portion and the end portion of the substrate 4 can be made uniform.

FIG. 2A is a perspective view showing a slit according to another embodiment of the present invention. The slit 11 is formed in a plate shape like the conventional slit, and is arranged at a predetermined angle with respect to the width direction of the substrate 4. FIG. 2 (B)
As shown in FIG. 3, since the circulation portion 16 is inclined at a predetermined angle with respect to the width direction of the substrate 4, the slurry 3b scraped by the coating thickness adjusting portion 15 is introduced into the coating thickness adjusting portion 15 together with the substrate 4. The slurry 3a flows down into the slurry tank 8 without joining.

As shown in FIG. 3, it is preferable that the base end portion of the slit 11 according to the present invention is rotatably supported by the support shaft 11a. With such a configuration, the angle θ between the circulation portion 16 of the slit 11 and the width direction of the substrate 4 can be adjusted, and the slurry flow can be optimized.

FIG. 4 is a side view showing an example of a rotating means for rotating the slit shown in FIG. As shown in FIG. 4, the rotating means 20 includes a moving member 21 having a long hole 21a into which the pin 11b attached to the tip of the slurry coating apparatus 1 is inserted, and the moving member 21 is vertically movable. The ball screw 2 supported by the ball screw 2, a motor 23 for rotating the ball screw 2, and a detent rod 24 arranged in parallel with the ball screw 2 and supporting the moving member 21.
According to the rotating means 20, the moving member 21 moves up and down by driving the motor 23 to rotate the ball screw 2, and accordingly, the slit 11 supported by the moving member 21 via the pin 11b is moved. , Can be rotated to a desired angle with the support shaft 11a as a fulcrum.

The rotating means of the slit 11 is not limited to the above-mentioned one, and for example, the tip of the rod of the piston device is rotatably attached to the tip of the slurry coating apparatus 1,
The slurry coating device 1 may be rotated by the expansion and contraction of the rod.

FIG. 5A is a perspective view showing a slit according to still another embodiment of the present invention. This slit 30
Is formed by notching the lower end of the diverting portion 36 in a mountain shape. According to the slit 30, the diverted portion 36 is formed so as to be inclined toward the both ends at a predetermined angle with respect to the width direction of the substrate 4, so that as shown in FIG. The scraped slurry 3b flows down into the slurry tank 8 from both ends of the slit 30 without joining the slurry 3a introduced into the coating thickness adjusting unit 35 together with the substrate 4.

The shape of the slit of the present invention is not limited to that of the above-mentioned embodiment, and for example, a pair of slits may be integrally formed.

FIG. 6 is a schematic explanatory view showing another slurry coating apparatus according to the present invention. As shown in FIG. 6, the slurry coating device 40 includes a slit 41 for introducing a long substrate 4 coated with the slurry 3 and adjusting a coating thickness of the slurry 3 coated on the substrate 4. Slurry receiver 42 for storing the slurry 3b scraped off by the slit 41
And a suction pump 43 for sucking the slurry 3b stored in the slurry receiver 42.

The slurry receiver 42 is arranged immediately below the circulation portion of the slit 41. Also, the slurry receiver 4
2 and the suction pump 43, and the suction pump 43 and the slurry tank 8 are connected by flexible tubes 44, respectively.

According to this slurry coating device 40, the slurry 3b scraped off by the slit 41 flows down along the circulation portion of the slit 41, and the slurry receiver 42
Stored in. Next, the slurry 3b stored in the slurry receiver 42 is sucked by the suction pump 43. Therefore, the slurry 3b scraped off by the slit 41 flows down without joining with the slurry 3a introduced into the slit 41 together with the substrate 4, so that the slurry coating thickness of the central portion and the end portion of the substrate 4 can be made uniform. it can. The sucked slurry 3b is returned to the slurry tank 8 containing the slurry 3 and is reused for coating the substrate 4.

The present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims.

[0025]

According to the slurry coating apparatus of the present invention, the slurry scraped by the slit flows down without flowing together with the slurry introduced into the slit together with the substrate. Therefore, when adjusting the slurry coating thickness, It is possible to make the slurry coating thickness uniform in the central portion and the end portion.

[Brief description of drawings]

FIG. 1A is a perspective view showing a slurry coating apparatus of the present invention, and FIG. 1B is a side view showing a state in which a slurry scraped off by a slit thereof flows down into a slurry tank.

FIG. 2A is a perspective view showing a slit of another embodiment according to the present invention, and FIG. 2B is a side view showing a state in which the slurry scraped off by the slit flows down into the slurry tank. .

FIG. 3 is a side view showing a slit according to another embodiment of the present invention, which is capable of adjusting a tilt angle with respect to a width direction of a substrate.

FIG. 4 is a side view showing a rotating means for rotating the slit shown in FIG.

5A is a perspective view showing a slit of still another embodiment according to the present invention, and FIG. 5B is a side view showing a state in which the slurry scraped off by the slit flows down into the slurry tank. is there.

FIG. 6 is a schematic explanatory view showing another slurry coating device according to the present invention.

FIG. 7 is a perspective view showing a conventional slit.

FIG. 8 is a side view showing a state in which the slurry scraped off by a conventional slit flows down into a slurry tank.

[Explanation of symbols]

 1: Slurry coating device 2: Slit 3: Slurry 4: Substrate 5: Coating thickness adjusting part 6: Flowing part 7: Vertical surface 8: Slurry tank 40: Slurry coating device 41: Slit 42: Slurry receiving 43: Suction pump 44: Flexible Tube

Claims (2)

[Claims] 1. A slurry coating apparatus comprising: a slurry tank; a substrate that moves upward in the slurry tank; and a slit that adjusts the thickness of the slurry excessively attached to the substrate. A slurry coating apparatus, which is inclined at a predetermined angle with respect to a width direction of a substrate so that the slurry scraped by the slit flows down together with the slurry introduced into the slit together with the substrate. 2. A slit for scraping off the slurry coated on a long substrate to adjust the coating thickness to a predetermined value, a slurry receiver for storing the slurry scraped off by the slit, and a slurry receiver for collecting the slurry. And a suction pump for sucking the slurry.