JP7533494B2 - Powder Separator - Google Patents

Description

This disclosure relates to a powder separation device.

As a conventional cyclone classifier, JP 2021-20156 A (Patent Document 1) discloses a technology in which an airflow adjustment device having an inverted truncated cone side is placed in an outlet pipe provided in the upper part of the housing. In the cyclone classifier described in Patent Document 1, the above-mentioned airflow adjustment device is provided to adjust the airflow of the gas introduced from the inlet pipe provided in the housing, and the powder particles generated by crushing the raw material alloy for sintered magnets with a jet mill are efficiently collected.

JP 2021-20156 A

When forming an electrode sheet for use in a battery, an electrode layer is formed on a metal foil using electrostatic spraying (FPS). In this case, a composite powder containing two or more powders of different sizes, such as the granules and carrier particles that make up the electrode, is used. It is possible to recover the composite powder remaining after film formation, and separate and reuse the recovered composite powder. In such cases, a device that can efficiently separate at least one powder from the composite powder with a simple configuration is required.

This disclosure has been made in consideration of the above problems, and the purpose of this disclosure is to provide a powder separation device that can efficiently separate at least one powder from a composite powder in which two or more powders are combined, with a simple configuration.

The powder separation device according to the present disclosure includes a main body including an upper part defining a truncated cone-shaped upper space into which a composite powder formed by compounding two or more powders is introduced, a lower part defining a lower space, and a sieve part disposed between the upper part and the lower part for separating at least one powder from the composite powder; an introduction part for introducing the composite powder into the upper space; a suction part connected to the lower part for sucking gas in the main body to generate an airflow in the main body; and a gas introduction part provided in the upper part so as to be switchable between an open state and a closed state, for introducing gas into the upper space in the open state. When gas in the main body is being sucked by the suction part, the state of the airflow in the main body is changed by switching between the open state and the closed state.

According to the above configuration, at least the upper space has a truncated cone-shaped space, so that when the gas inlet section provided in the upper part is closed and the gas in the main body section is sucked in by the suction section, a swirling air current is generated in the upper space so as to move downward. This allows the composite powder introduced from the inlet section to the upper space to be guided to the sieve section over a wide range. At this time, powder of the composite powder that is equal to or smaller than a predetermined size passes through the sieve section, and at least one powder can be separated from the composite powder. In this way, by generating a swirling air current and separating the composite powder in the sieve section, the composite powder can be separated with a simple configuration.

When the composite powder is separated by the sieve section, powders larger than a certain size accumulate on the sieve section, making it difficult for powders smaller than the certain size of the composite powder to pass through the sieve section. In such a case, while the gas in the main body section is being sucked in by the suction section, the gas inlet section provided in the upper side section is opened from a closed state to change the state of the air flow in the main body section, generating a turbulent air flow. This moves the powders larger than the certain size that have accumulated on the sieve section, and improves the clogging state of the sieve section. In this way, by switching between the open and closed states of the gas inlet section and sucking in the gas in the main body section while changing the state of the air flow, at least one powder can be efficiently separated from the composite powder.

In the powder separation device based on the present disclosure, the composite powder may include a granule containing an electrode active material and a binder, and carrier particles. In this case, the granule and the carrier particles may be electrostatically bonded.

As described above, even in cases where the granules and carrier particles are strongly bonded together by electrostatic forces, the powder separation device can effectively separate the granules and carrier particles.

In the powder separation device based on the present disclosure, the carrier particles may be primarily composed of ferrite.

As described above, even if the carrier particles are mainly composed of ferrite and are heavy powders, changing the airflow conditions as described above can improve the clogging condition of the sieve section and efficiently separate at least one powder from the composite powder.

In the powder separation device based on the present disclosure, the main body may include a support portion disposed between the sieve portion and the lower side portion and supporting the sieve portion. The sieve portion may include a cylindrical body portion connected to the lower end of the upper side portion and a first mesh portion provided on the lower end side of the body portion. The support portion may include a cylindrical portion connecting the upper end of the body portion and the lower side portion and a second mesh portion provided on the cylindrical portion. In this case, it is preferable that the second mesh portion has a coarser mesh than the first mesh portion and supports the first mesh portion.

According to the above configuration, by supporting the first mesh part with the second mesh part having a coarser mesh than the first mesh part, it is possible to reinforce the first mesh part with almost no effect on the mesh opening of the first mesh part.

In the powder separation device based on the present disclosure, the gas introduction section may include an opening provided in the upper side portion and a shutter section that can open and close the opening.

According to the above configuration, the gas introduction section can be easily switched between an open state and a closed state by opening and closing the opening with the shutter section.

In the powder separation device based on the present disclosure, the upper portion may have a connection port connected to the introduction part, and the introduction part may be provided detachably on the connection port. In this case, the gas introduction part may be composed of the connection port and the introduction part. Furthermore, in this case, it is preferable that when the introduction part is attached to the connection port, the connection port is closed to achieve the closed state, and when the introduction part is detached from the connection port, the connection port is opened to allow gas to be introduced into the upper space.

With the above configuration, the gas introduction section can be easily switched between an open state and a closed state by switching the attachment/detachment state of the introduction section.

According to the present disclosure, it is possible to provide a powder separation device that can efficiently separate at least one powder from a composite powder in which two or more powders are combined, using a simple configuration.

1 is a schematic diagram of a powder separating device according to a first embodiment. FIG. 2 is a schematic cross-sectional view of a main body according to the first embodiment. FIG. 3 is a schematic diagram showing a sieve unit and a support unit of the powder separating device according to the first embodiment. FIG. 5 is a diagram showing an air flow in a main body when a gas inlet is in a closed state in the powder separating device according to the first embodiment. FIG. 10 is a diagram showing an air flow in a main body when a gas inlet is in an open state in the powder separating device according to embodiment 1. FIG. FIG. 11 is a schematic diagram of a powder separating device according to a second embodiment.

The following describes in detail the embodiments of the present disclosure with reference to the drawings. Note that in the embodiments described below, identical or common parts are given the same reference numerals in the drawings, and their description will not be repeated.

(Embodiment 1)
Fig. 1 is a schematic diagram of a powder separating device according to embodiment 1. Fig. 2 is a diagram showing a cross section of a main body according to embodiment 1. The powder separating device 100 according to embodiment 1 will be described with reference to Figs. 1 and 2.

The powder separation device 100 is a device for separating at least one powder from a composite powder in which two or more powders are combined.

As the composite powder, one containing a granule containing an electrode active material and a binder, and carrier particles can be used. Note that the composite powder is not limited to the above, and is not particularly limited as long as it can be separated by the sieve unit 30 described below.

The granules may be, for example, granules for a positive electrode containing a positive electrode active material, a binder, and a conductive material. In this case, a known positive electrode active material such as lithium cobalt oxide may be appropriately used as the positive electrode active material. Specifically, NCM (lithium nickel cobalt manganese oxide) may be used as the positive electrode active material. In addition, a fluorine-containing resin such as polyvinylidene fluoride (PVDF) may be used as the binder. A known conductive material such as vapor grown carbon fiber (VGCF) or acetylene black may be used as the conductive material. The composition ratio of the positive electrode active material, conductive material, and binder may be, for example, positive electrode active material:conductive material:binder=90:5:5 (wt%). Note that the composition ratio is not limited to the above.

The granules for the positive electrode are obtained, for example, by compounding three types of powders, the positive electrode active material, the conductive material, and the binder, using an MP mixer (manufactured by Nippon Coke Co., Ltd.), and then heat-treating the compound at a predetermined temperature.

The granules may be, for example, granules for the negative electrode containing a negative electrode active material and a binder. In this case, the negative electrode active material may be, for example, a known carbon-based negative electrode mixture containing graphite or the like. As described above, the binder may be, for example, a fluorine-containing resin such as polyvinylidene fluoride (PVDF). The composition ratio of the negative electrode active material and the binder may be, for example, negative electrode active material:binder=97.5:2.5 (wt%). The composition ratio is not limited to the above. The negative electrode granules may also contain a known conductive material such as acetylene black.

The granules for the negative electrode can be obtained, for example, by compounding two types of powder, the negative electrode active material and the binder, in a high-speed mixer.

The carrier particles may be, for example, those mainly composed of ferrite. The carrier particles have a larger particle size and are heavier than the granules for the positive electrode and the granules for the negative electrode.

The positive electrode granules or negative electrode granules and the above carrier particles can be mixed in a roll mill to obtain a composite powder.

As shown in Figures 1 and 2, the powder separation device 100 according to the first embodiment includes a main body 1, an introduction section 50, a suction section 60, and a gas introduction section 70. The main body 1 has an upper side section 10, a lower side section 20, a sieve section 30, and a support section 40.

The upper portion 10 constitutes the upper side of the outer casing of the main body 1 and defines the upper space S1. The upper space S1 has a truncated cone shape. The upper portion 10 has an upper end 11 and a lower end 12, and has a cylindrical shape that tapers toward the upper end 11. The upper end 11 is provided with a connection port 11a to which the introduction section 50 is connected. The lower end 12 is provided with an opening that communicates with the inside of the sieve section 30.

A gas introduction section 70 is provided on the side of the upper portion 10. The gas introduction section 70 is provided so that it can be switched between an open state and a closed state. When in the open state, the gas introduction section 70 can introduce gas into the upper space S1. On the other hand, when in the closed state, the gas introduction section 70 cannot introduce gas into the upper space S1. The gas introduced into the upper space S1 may be outside air or gas supplied via a supply pipe (not shown).

The gas introduction section 70 is composed of an opening 13 provided on the side of the upper portion 10 and a shutter section 14 that closes the opening 13 in an openable and closable manner. The open state is when the shutter section 14 is open. The closed state is when the shutter section 14 is closed. The opening and closing operation of the shutter section 14 can be performed, for example, by driving a drive source (not shown).

The lower portion 20 constitutes the lower side of the outer casing of the main body 1 and defines the lower space S2. The lower space S2 has an inverted truncated cone shape. The lower portion 20 has an upper end 22 and a lower end 21, and has a cylindrical shape that tapers toward the lower end 21. The lower end 21 has an opening 21a that communicates with the suction section 60.

The sieve section 30 is disposed between the upper side section 10 and the lower side section 20. When the composite powder passes through the sieve section 30, the sieve section 30 separates at least one powder from the composite powder.

The support section 40 is disposed between the sieve section 30 and the lower side section 20. The support section 40 supports the sieve section 30. Details of the sieve section 30 and the support section 40 will be described later with reference to FIG. 3.

The introduction section 50 is a section for introducing the composite powder into the upper space S1. The introduction section 50 forms a flow path through which the composite powder flows. The introduction section 50 has a generally cylindrical shape. The introduction section 50 is connected to the connection port 11a.

The suction unit 60 is connected to the lower portion 20 and generates an airflow within the main body 1 by sucking in the gas within the main body 1. The suction unit 60 is connected to the opening 21a of the lower portion 20.

Figure 3 is a schematic diagram showing the sieve section and support section of the powder separation device according to embodiment 1.

As shown in FIG. 3, the sieve section 30 has a body section 31 and a first mesh section 32. The body section 31 has a cylindrical shape. The body section 31 is connected to the lower end 12 of the upper side section 10. The inner space of the body section 31 is connected to the upper side space S1. The first mesh section 32 is provided on the lower end side of the body section 31. The first mesh section 32 is formed so that at least one of the composite powders cannot pass through it. Specifically, the first mesh section 32 is formed so that the positive electrode granules or the negative electrode granules can pass through it, but the carrier particles cannot pass through it.

The support section 40 has a cylindrical section 41 and a second mesh section 42. The cylindrical section 41 connects the lower end of the body section 31 and the upper end 22 of the lower side section 20. The internal space of the cylindrical section 41 is connected to the internal space of the body section 31 and the lower side space S2. The second mesh section 42 has a coarser mesh than the first mesh section 32 and supports the first mesh section 32. This makes it possible to reinforce the first mesh section 32 without affecting the mesh opening of the first mesh section 32. As described above, when the carrier particles are mainly composed of ferrite and are heavy, it is possible to suppress distortion of the first mesh section 32 due to the weight of the accumulated carrier particles.

Figure 4 shows the airflow inside the main body of the powder separation device according to embodiment 1 when the gas introduction section is in a closed state.

As shown in FIG. 4, when the gas introduction section 70 is closed and the suction section 60 is driven, a swirling flow is generated inside the main body section 1. Specifically, in the upper space S1, a swirling flow is generated whose diameter increases as it moves downward, and in the lower space S2, a swirling flow is generated whose diameter decreases as it moves downward.

By generating the above-mentioned swirling flow in the upper space S1, the composite powder introduced from the introduction section 50 into the upper space S1 can be guided over a wide area to the sieve section 30 (more specifically, the first mesh section 32). In addition, when the composite powder passes through the sieve section 30, the powder that cannot pass through the first mesh section 32 is separated from the other powder. Specifically, the carrier particles are separated from the granulated material, and the carrier particles remain on the first mesh section 32.

When the suction section 60 is driven continuously for a predetermined time in the closed state, carrier particles accumulate on the first mesh section 32. In such a case, powder particles of the composite powder that are smaller than a predetermined size are less likely to pass through the sieve section 30.

Figure 5 shows the airflow inside the main body of the powder separation device according to embodiment 1 when the gas inlet is in an open state.

As shown in FIG. 5, when the gas introduction section 70 is opened while the suction section 60 is driven, gas is introduced from the gas introduction section 70 into the upper space S1. At this time, the state of the airflow inside the main body section 1 changes, and turbulent airflow occurs. Specifically, for example, airflows as shown by arrows AR2 and AR3 are generated. Such airflows can move powder particles of a certain size or larger that have accumulated in the sieve section 30 (first mesh section 32), and can improve the clogging state of the sieve section 30.

As described above, by switching the gas inlet section 70 between the open and closed states and sucking in the gas inside the main body section 1 while changing the state of the airflow, at least one or more powder particles can be efficiently separated from the composite powder. In addition, as described above, by generating a swirling airflow and separating the composite powder in the sieve section 30, the composite powder can be separated with a simple configuration.

(Embodiment 2)
Fig. 6 is a schematic diagram of a powder separating apparatus according to embodiment 2. A powder separating apparatus 100A according to embodiment 2 will be described with reference to Fig. 6 .

As shown in FIG. 6, the powder separation device 100A differs from the powder separation device 100 according to embodiment 1 in the configuration of the gas introduction section 70A. The other configurations are almost the same.

In the second embodiment, the gas introduction section 70A is composed of the connection port 11a and the introduction section 50. The introduction section 50 is detachably provided to the connection port 11a. Specifically, the introduction section 50 is provided so as to be movable in the up and down direction (arrow DR1 direction) by a drive source (not shown).

When the introduction part 50 is attached to the connection port 11a, the connection port 11a is closed, and the gas introduction part 70A is in a closed state. On the other hand, when the introduction part 50 is removed from the connection port 11a, the gas introduction part 70 is in an open state, and gas is introduced from the connection port 11a into the upper space S1.

Even when configured in this manner, the powder separation device 100A according to embodiment 2 provides substantially the same effects as the powder separation device 100 according to embodiment 1.

The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims.

1 main body, 10 upper side portion, 11 upper end, 11a connection port, 12 lower end, 13 opening, 14 shutter portion, 20 lower side portion, 21 lower end, 21a opening, 22 upper end, 30 sieve portion, 31 body portion, 32 first mesh portion, 40 support portion, 41 cylindrical portion, 42 second mesh portion, 50 introduction portion, 60 suction portion, 70, 70A gas introduction portion, 100, 100A powder separation device.

Claims (4)

a main body including an upper portion defining a truncated cone-shaped upper space into which a composite powder formed by compounding two or more powders is introduced, a lower portion defining a lower space, and a sieve portion disposed between the upper portion and the lower portion for separating at least one powder from the composite powder;
an introduction portion for introducing the composite powder into the upper space;
a suction section connected to the lower portion and configured to suck gas from within the main body section to generate an airflow within the main body section;
a gas introduction section that is provided in the upper portion so as to be switchable between an open state and a closed state and that introduces gas into the upper space in the open state;
A powder separating device which changes the state of the airflow within the main body portion by switching between the open state and the closed state while the gas within the main body portion is being sucked in by the suction portion. The powder separation device according to claim 1, wherein the composite powder includes a granule containing an electrode active material and a binder, and a carrier particle, and the granule and the carrier particle are electrostatically bonded. The powder separation device according to claim 2, wherein the carrier particles are mainly composed of ferrite. The main body portion includes a support portion disposed between the sieve portion and the lower side portion and configured to support the sieve portion;
The sieve portion includes a cylindrical body portion connected to a lower end of the upper portion, and a first mesh portion provided on the lower end side of the body portion,
the support portion includes a cylindrical portion connecting a lower end of the body portion and an upper end of the lower portion side portion, and a second mesh portion provided on the cylindrical portion,
The powder separating device according to claim 1 , wherein the second mesh portion has coarser meshes than the first mesh portion and supports the first mesh portion.

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