JP6793629B2 - Vertical drop type powder heating device - Google Patents

Description

The present disclosure relates to a vertical drop type powder heating device that heats powder while dropping it.

Conventionally, a vertical drop type powder heating device that heats powder while dropping it has been known (see, for example, Patent Documents 1 and 2).

The powder heating device of Patent Documents 1 and 2 includes a cylindrical body extending in the vertical direction and a heater arranged around the cylindrical body. While the powder is freely dropped in the cylindrical body, the falling powder is heated from the outside by a surrounding heater.

Patent No. 5730656 Japanese Unexamined Patent Publication No. 2-74519

However, in the cylindrical body, the powder is easily heated on the outside near the heater, whereas the powder is not easily heated on the inside far from the heater. This causes uneven heating of the powder. On the other hand, when heating the powder, it is desirable to heat it to a temperature as uniform as possible, and the vertical drop type powder heating apparatus of Patent Documents 1 and 2 described above is improved in that the powder is heated uniformly. It can be said that there is room for.

The present disclosure is to solve the above-mentioned problems, and an object of the present invention is to provide a vertical drop type powder heating device capable of heating powder more uniformly.

The vertical drop-type powder heating device according to one aspect of the present disclosure is a drop-type powder heating device that heats powder while dropping it, and is a drop-type powder heating device that has a charging port for charging powder and below the charging port. A heating flow path forming portion provided between the inlet and the outlet for taking out the heated powder, and a heating flow path forming portion forming a heating flow path extending in the vertical direction, and a heating flow path forming portion. The heating flow path forming portion includes a first heater arranged around the inner wall, and the heating flow path forming portion includes an inner wall extending in a vertical direction and an outer wall extending in a vertical direction at a position surrounding the inner wall at intervals from the outside. To form an annular heating flow path between the inner wall and the outer wall.

According to the above configuration, by forming the annular flow path, uneven heating of the powder by the heater is suppressed and the powder is heated more uniformly and faster than in the case of forming one non-annular flow path. can do.

In the vertical drop type powder heating device, the upper end portion of the inner wall of the heating flow path forming portion may have an inclined surface inclined so as to spread outward toward the lower side. As a result, the powder falling from the charging port can be scattered toward the outside near the heater, and the powder can be heated more uniformly.

In the vertical drop type powder heating device, a groove and / or a protrusion may be formed on the inclined surface of the upper end portion. As a result, it is possible to make it easier for the powder that has fallen from the inlet to slide off the inclined surface and to disperse the powder evenly in the circumferential direction.

In the vertical drop type powder heating device, the vertical drop type powder heating device has an inclined surface inclined so as to spread downward and rotates in the circumferential direction below the inlet and above the inner wall of the heating flow path forming portion. A rotating body may be provided. As a result, the powder falling from the charging port can be scattered toward the outside near the heater, and the powder can be heated more uniformly.

In the vertical drop type powder heating device, grooves and / or protrusions may be formed on the inclined surface of the rotating body. As a result, it is possible to make it easier for the powder that has fallen from the inlet to slide off the inclined surface and to disperse the powder evenly in the circumferential direction.

In the vertical drop type powder heating device, a box-shaped structure in which a flow path through which powder flows is formed inside and rotates in the circumferential direction below the inlet and above the inner wall of the heating flow path forming portion. The rotating body may be provided with an upstream opening communicating with the inlet and a downstream opening communicating with the upstream opening laterally. As a result, the powder falling from the charging port can be scattered toward the outside near the heater, and the powder can be heated more uniformly.

In the vertical drop type powder heating device, a second heater may be further provided inside the inner wall of the heating flow path forming portion. As a result, uneven heating of the powder can be further suppressed.

According to the vertical drop type powder heating device of the present disclosure, the powder can be heated more uniformly and quickly.

Schematic longitudinal sectional view of the powder heating device of the first embodiment Schematic longitudinal sectional view of the powder heating device of the second embodiment Schematic vertical cross-sectional view of the powder heating device of the third embodiment Schematic vertical sectional view of the powder heating device of the fourth embodiment Schematic perspective view of the second flow path forming member in the rotating body of the powder heating device of the fourth embodiment. Schematic perspective view showing protrusions and grooves in a modified example Schematic vertical cross-sectional view of the powder heating device in the modified example

Hereinafter, a preferred embodiment of the powder heating apparatus according to the present disclosure and the powder heating method using the same will be described with reference to the accompanying drawings. The present disclosure is not limited to the specific configuration of the following embodiments, and the present disclosure includes configurations based on the same technical idea.

(Embodiment 1)
FIG. 1 is a vertical cross-sectional view showing a schematic configuration of the powder heating device 2 according to the first embodiment.

The powder heating device 2 shown in FIG. 1 is a vertical drop type powder heating device that heats the powder P as an object to be processed while dropping it. The powder P is, for example, an inorganic material powder, a carbon powder, a fine metal piece, and a magnetic material powder, but is not limited thereto.

The powder heating device 2 shown in FIG. 1 includes a main body 4 and a heater 6.

The main body 4 is a member that forms a flow path for heat-treating the powder P. A heat-resistant material such as metal is used for the main body 4. The heater 6 is a member that heats the powder P flowing through the flow path in the main body 4 mainly from the outside by radiant heat.

The main body 4 includes an inlet 8, an outlet 10, an inner wall 12, an outer wall 14, a valve V1, and a valve V2.

The charging port 8 is an opening for charging the powder P. The input port 8 is provided at the uppermost portion of the main body 4 in the vertical direction (vertical direction) Z. A powder supply unit (not shown) for supplying powder P at room temperature is provided above the charging port 8. The temperature of the powder P charged into the charging port 8 is, for example, room temperature.

The outlet 10 is an opening for taking out the heated powder P below the inlet 8. The outlet 10 is located at the lowermost part of the main body 4 in the vertical direction Z. Below the outlet 10, a powder recovery unit (not shown) for recovering the powder P after the heat treatment is provided. The temperature of the powder P after the heat treatment taken out from the outlet 10 is, for example, 100 ° C. to 300 ° C.

Both the inner wall 12 and the outer wall 14 are members extending in a tubular shape in the vertical direction Z. The inner wall 12 and the outer wall 14 in the first embodiment both have a substantially cylindrical shape and are arranged concentrically. The inner wall 12 having a small outer diameter is arranged inside, and the outer wall 14 having a large outer diameter is arranged outside. The outer wall 14 is arranged at a position that surrounds the inner wall 12 at a distance from the outside.

An annular flow path is formed between the inner wall 12 and the outer wall 14 for the powder P to fall and pass through.

The inner wall 12 includes a first inclined portion 12a, a central portion 12b, and a second inclined portion 12c. The first inclined portion 12a, the central portion 12b, and the second inclined portion 12c form an integral inner wall 12.

The first inclined portion 12a is a portion constituting the upper end portion of the inner wall 12. The first inclined portion 12a shown in FIG. 1 has a conical outer shape whose diameter is expanded downward (diameter is reduced upward), and the upper end thereof is closed. That is, the outer surface of the first inclined portion 12a is an inclined surface inclined obliquely downward from the center side of the main body portion 4 toward the outside. The central angle θ of the cone of the first inclined portion 12a may be set to an arbitrary angle as long as the powder P can slide down, and may be set to, for example, 45 degrees to 60 degrees. The tip of the first inclined portion 12a coincides with the center position of the upper end portion 14a, which will be described later, in the vertical direction.

The central portion 12b is a portion connecting between the first inclined portion 12a and the second inclined portion 12c. The central portion 12b shown in FIG. 1 has a cylindrical shape extending in the vertical direction Z.

The second inclined portion 12c is a portion constituting the lower end portion of the inner wall 12. The second inclined portion 12c shown in FIG. 1 has a truncated cone-shaped outer shape whose diameter is expanded upward (diameter is reduced downward). That is, the outer surface of the second inclined portion 12c is an inclined surface inclined obliquely downward from the outside of the main body portion 4 toward the center side. While the first inclined portion 12a described above is closed, the lower end of the second inclined portion 12c is open to form an opening 12d.

The outer wall 14 includes an upper end portion 14a, a first inclined portion 14b, a central portion 14c, a second inclined portion 14d, and a lower end portion 14e. An integral outer wall 14 is formed by the upper end portion 14a, the first inclined portion 14b, the central portion 14c, the second inclined portion 14d, and the lower end portion 14e.

The upper end portion 14a is a portion constituting the upper end portion of the outer wall 14. The upper end portion 14a forms an input port 8 and extends downward from the input port 8. The upper end portion 14a shown in FIG. 1 has a cylindrical shape extending in the vertical direction Z.

The first inclined portion 14b is a portion connecting the upper end portion 14a and the central portion 14c. The first inclined portion 14b shown in FIG. 1 has a truncated cone-shaped outer shape whose diameter increases downward. The outer surface of the first inclined portion 14b is an inclined surface inclined obliquely downward from the center side of the main body portion 4 toward the outside. The first inclined portion 14b is arranged at a position facing the first inclined portion 12a of the inner wall 12 described above, and is set at substantially the same inclination angle as the first inclined portion 12a.

The central portion 14c is a portion connecting between the first inclined portion 14b and the second inclined portion 14d. The central portion 14c shown in FIG. 1 has a cylindrical shape extending in the vertical direction. Heaters 6 are provided on the outside of the central portion 14c with a slight interval.

The second inclined portion 14d is a portion connecting the central portion 14c and the lower end portion 14e. The second inclined portion 14d shown in FIG. 1 has a truncated cone-like outer shape whose diameter is expanded upward. The outer surface of the second inclined portion 14d is an inclined surface inclined obliquely downward from the outside of the main body portion 4 toward the center side. The second inclined portion 14d is arranged at a position facing the second inclined portion 12c of the inner wall 12 described above, and is set at substantially the same inclination angle as the second inclined portion 12c.

The lower end portion 14e is a portion constituting the lower end portion of the outer wall 14. The lower end portion 14e forms an outlet 10 and extends downward toward the outlet 10. The lower end portion 14e shown in FIG. 1 has a cylindrical shape extending in the vertical direction Z.

The valve V1 is a valve provided at the upper end portion 14a of the outer wall 14 in the vicinity of the inlet 8. By opening and closing the valve V1, it is possible to control the injection of the powder P into the main body 4. The valve V2 is a valve provided at the lower end portion 14e of the outer wall 14 in the vicinity of the outlet 10. By opening and closing the valve V2, the extraction of the powder P from the main body 4 can be controlled. When the valves V1 and V2 are closed, the flow path of the powder P, which is the internal space of the main body 4, is sealed.

In the above configuration, when the valve V1 is opened and the powder P is charged from the charging port 8, the charged powder P freely falls in the main body 4 and falls on the first inclined portion 12a which is the upper end of the inner wall 12. To reach. Since the outer surface of the first inclined portion 12a is an inclined surface inclined downward from the center side to the outside, the powder P moves on the surface of the first inclined portion 12a while sliding from the center side to the outside. The powder P that slides outward on the first inclined portion 12a and falls is guided by the annular flow path formed by the inner wall 12 and the outer wall 14.

The powder P freely falls downward in the annular flow path and is heated mainly by radiant heat by the heater 6 provided on the outside of the main body 4. The powder P is heated to, for example, 500 ° C. to 1000 ° C. in the process of dropping through the annular flow path.

The heated powder P is discharged to the outside from the outlet 10 in a state where the valve V2 is opened, and is recovered. When the powder P is discharged to the outside from the outlet 10, the powder P dissipates heat and the temperature drops to 100 ° C to 300 ° C.

According to the above configuration, the powder P is heated in the annular flow path formed between the inner wall 12 and the outer wall 14. By forming such an annular flow path, when one non-annular flow path is formed, that is, the space inside the outer wall 14 without the presence of the inner wall 12 becomes the flow path of the powder P. Compared with the case, the variation in heating intensity due to the heater 6 in the radial direction X becomes smaller. As a result, uneven heating of the powder P can be suppressed, and the powder P can be heated more uniformly.

For example, in the case of one non-annular flow path, in order to keep all the falling powder P at a predetermined temperature or higher, the main body 4 is based on the falling time of the powder P near the center where the temperature rise is the slowest. It is conceivable to determine the length of Z in the vertical direction. However, since the height of the ceiling of the site where the powder heating device is installed and the ceiling of the factory is limited, it is desired that the height of the powder heating device is as low as possible. On the other hand, according to the powder heating device 2 of the first embodiment, since all the powder P passes through the region close to the heater 6, the difference in temperature rise depending on the position in the radial direction X can be reduced, and the powder P is heated at a high temperature. it can. Further, since the powder heating device 2 can be designed based on the falling time of the powder P in the vicinity of the outer wall 14 where the temperature rises quickly, the height of the powder heating device 2 can be lowered. If the height of the powder heating device 2 can be lowered, the time required for producing the powder P can be shortened by the amount that the falling time of the powder P due to the temperature rise is shortened.

Further, in the case of using one non-annular flow path, if the diameter of the main body 4 is reduced, the temperature difference between the powder P near the center of the main body 4 and the powder P near the outer wall 14 can be reduced. Since the flow path is narrow, the production amount of powder P is reduced. On the other hand, according to the powder heating device 2 of the first embodiment, the production amount of the powder P can be increased by increasing the diameter of the outer wall 14, and the width of the flow path can be increased by increasing the diameter of the inner wall 12. By narrowing, the temperature difference of the powder P can be reduced.

Further, according to the powder heating device 2 of the first embodiment, the first inclined portion 12a, which is the upper end portion of the inner wall 12, has an inclined surface inclined downward from the center side toward the outside, and the upper end is closed. ing. According to such a configuration, the powder P that has fallen from the input port 8 slides along the first inclined portion 12a and falls from the center side to the outside. As a result, the powder P can be dispersed toward the outside close to the heater 6, and the powder P can be heated more uniformly.

Further, according to the powder heating device 2 of the first embodiment, the second inclined portion 12c is further connected and extended under the central portion 12b of the inner wall 12. According to such a configuration, it is possible to make it difficult for the powder P that has passed through the annular flow path to enter the internal space of the inner wall 12 as compared with the case where the second inclined portion 12c is not provided.

Further, according to the powder heating device 2 of the first embodiment, the second inclined portion 12c, which is the lower end portion of the inner wall 12, is not closed and is open. According to such a configuration, unlike the case where the lower end portion of the inner wall 12 is closed, the internal space of the inner wall 12 is not sealed, so that the air in the inner space expands and the pressure becomes excessively high, and the inner wall 12 is deformed. However, it is possible to prevent the annular flow path from becoming too narrow. Thereby, the reliability of the powder heating device 2 can be improved.

(Embodiment 2)
The powder heating device 20 of the second embodiment according to the present disclosure will be described with reference to FIG. In the second embodiment, the points different from the first embodiment will be mainly described, and the description overlapping with the first embodiment will be omitted. Further, the same or equivalent configurations as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the powder heating device 20 of the second embodiment shown in FIG. 2, in addition to the heater (first heater) 6 provided on the outside of the outer wall 14, another heater (second heater) 22 is provided inside the inner wall 12. Further, it is different from the powder heating device 2 of the first embodiment in that it is provided.

By providing the second heater 22 in addition to the first heater 6, the heating of the powder P passing through the inside of the annular flow path can be promoted. As a result, the powder P can be heated more uniformly and quickly, and uneven heating of the powder P can be further suppressed.

(Embodiment 3)
The powder heating device 30 of the third embodiment according to the present disclosure will be described with reference to FIG. In the third embodiment, the points different from the first embodiment will be mainly described, and the description overlapping with the first embodiment will be omitted. Further, the same or equivalent configurations as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The powder heating device 30 of the third embodiment shown in FIG. 3 is provided with a rotating body 32 that rotates in the circumferential direction R below the charging port 8 and above the inner wall 35. Different from 2.

The rotating body 32 is a rotating body having a function of scattering the powder P falling from the input port 8 from the center side to the outside. The rotating body 32 includes a rotating portion 34, a rotating shaft 36, a motor 38, a first heat insulating material 40, and a second heat insulating material 42.

The rotating portion 34 is a member that is rotated in the circumferential direction R about the rotating shaft 36. The rotating portion 34 shown in FIG. 3 has a conical shape whose diameter is increased downward (reduced diameter upward). That is, the outer surface of the rotating portion 34 is an inclined surface that is inclined so as to spread outward from the upper side to the lower side. The rotating portion 34 is provided above the inner wall 35. The rotating portion 34 is connected to the motor 38 via a rotating shaft 36. The rotation shaft 36 is a shaft extending in the vertical direction Z. The motor 38 is a member that rotates the rotating portion 34 by rotating the rotating shaft 36. The motor 38 is attached to the back surface of the first heat insulating material 40. The first heat insulating material 40 and the second heat insulating material 42 are members for insulating the motor 38 from the surrounding heating region. The first heat insulating material 40 is provided so as to cover the upper end portion of the inner wall 35. The second heat insulating material 42 is attached to the inner surface of the inner wall 35 so as to be continuous with the first heat insulating material 40.

According to such a configuration, the powder P falling from the input port 8 reaches the upper surface (inclined surface) of the rotating portion 34. Since the rotating portion 34 rotates in the circumferential direction R, the powder P is blown from the center side to the outside by the rotation of the rotating portion 34. As a result, the powder P can be uniformly dispersed and dispersed outside near the heater 6 and guided to the annular flow path. Therefore, uneven heating of the powder P can be further suppressed, and the powder P can be heated more uniformly and quickly.

(Embodiment 4)
The powder heating device 50 of the fourth embodiment according to the present disclosure will be described with reference to FIGS. 4 and 5. In the fourth embodiment, the points different from the third embodiment will be mainly described, and the description overlapping with the third embodiment will be omitted. Further, the same or equivalent configurations as those in the third embodiment are designated by the same reference numerals and the description thereof will be omitted.

The powder heating device 30 of the third embodiment shown in FIG. 3 includes a rotating body 32 having a conical rotating portion 34, whereas the powder heating device 50 of the fourth embodiment shown in FIG. 4 has a box shape. It is different from the third embodiment in that the rotating body 52 is provided.

The rotating body 52 is a rotating body having a function of scattering the powder P falling from the inlet 8 to the outside by centrifugal force. The rotating body 52 includes a box portion 53, a rotating shaft 36, a motor 38, a first heat insulating material 40, and a second heat insulating material 42.

The box portion 53 is a box-shaped member that forms a flow path for the powder P that is charged from the charging port 8. The upstream opening 54 of the box portion 53 is provided above the box portion 53 so as to be connected to the input port 8. The downstream opening 56 of the box portion 53 communicates with the upstream opening 54 and is provided on the side of the box portion 53. The downstream opening 56 faces outward from the center side above the inner wall 35.

A charging portion 58 for charging the powder P is connected to the upstream opening 54 of the box portion 53. The loading portion 58 is a tubular member forming the loading port 8, and is connected to the box portion 53 as shown in FIG.

A schematic perspective view of the box portion 53 is shown in FIG. As shown in FIG. 5, the box portion 53 forms a plurality of flow paths 62 by a plurality of blades 61 extending radially from the center side to the outside.

In such a configuration, the powder P that has entered the box portion 53 from the charging port 8 of the charging portion 58 is rotated from the center side by centrifugal force because the box portion 53 is rotated about the rotation shaft 36 by the motor 38. It is blown outward. As a result, the powder P is guided to the annular flow path while being blown outward from the downstream opening 56. As a result, the powder P can be dispersed to the outside close to the heater 6, and the powder P can be heated more uniformly and quickly.

Although the invention of the present disclosure has been described above with reference to the above-described embodiments 1-4, the invention of the present disclosure is not limited to the above-described embodiments 1-4. For example, in the first and second embodiments, the case where the inclined surfaces of the first inclined portion 12a and the rotating portion 34 are flat has been described, but not limited to such a case, protrusions and / or grooves may be provided. .. Specifically, as shown in FIGS. 6A and 6B, for example, plate-shaped protrusions 70 and 80 may be provided so that the powder P may be evenly dispersed from the center side to the outside. At this time, grooves 72 and 82 are formed between the protrusions 70 and between the protrusions 80, respectively. In this case, the shapes of the protrusions 70 and 80 and the grooves 72 and 82 may be concentric or spiral. Further, as shown in FIG. 6C, a plurality of protrusions 90 may be provided so as to disperse the powder P while dropping.

Further, in the first and third embodiments, the case where the outer shape of the first inclined portion 12a of the inner wall 12 and the rotating portion 34 of the rotating body 32 has a conical shape protruding upward has been described, but the case is not limited to such a case. These shapes may be any shape as long as they have an inclined surface that is inclined outward toward the lower side.

Further, in the fourth embodiment, the case where the box portion 53 of the rotating body 52 has the shape as shown in FIGS. 4 and 5 has been described, but the case is not limited to such a case. The shape of the box portion 53 may be any shape as long as the flow path of the powder P charged from the charging port 8 is formed inside and the powder P is blown outward by centrifugal force. ..

Further, the rotating portion 34 shown in FIG. 3 and the rotating body 52 shown in FIG. 4 may be interchangeable. Further, the rotation direction of the rotating body 34 and the rotating body 52 may be either left or right.

Further, in the first embodiment, a case where the central portion 14c of the outer wall 14 facing the first heater 6 has a vertical length as shown in FIG. 1 has been illustrated, but the case is not limited to such a case. For example, as shown in FIG. 7, the central portion 24c of the outer wall 14 and the central portion 22b of the inner wall 12 may be extended downward. As a result, a cooling zone 60 capable of cooling the powder P can be provided in a region of the central portions 24c and 22b that does not face the heater 6. The cooling in the cooling zone 60 may be any cooling method such as natural air cooling, forced air cooling by a blower (not shown), and water cooling by a water cooling jacket.

Although the present disclosure has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various modifications and modifications are obvious to those skilled in the art. It should be understood that such modifications and amendments are included within the scope of the present disclosure by the appended claims. In addition, changes in the combination and order of elements in each embodiment can be realized without departing from the scope and ideas of the present disclosure.

By appropriately combining any of the above-mentioned various embodiments, the effects of each can be achieved.

The present disclosure is applicable to any vertical drop type powder heating device that heats powder while dropping it.

2 Powder heating device (vertical drop type powder heating device)
4 Main body 6 Heater (first heater)
8 Input port 10 Outlet 12 Inner wall 12a First inclined part 12b Central part 12c Second inclined part 12d Opening 14 Outer wall 14a Upper end part 14b First inclined part 14c Central part 14d Second inclined part 14e Lower end part 20 Powder Body heating device (vertical drop powder heating device)
22 heater (second heater)
22b Central part 24c Central part 30 Powder heating device (vertical drop type powder heating device)
32 Rotating body 34 Rotating part 35 Inner wall 36 Rotating shaft 38 Motor 40 First heat insulating material 42 Second heat insulating material 50 Powder heating device (vertical drop type powder heating device)
52 Rotating body 53 Box part 54 Upstream opening 56 Downstream opening 58 Input part 60 Cooling zone 61 Blade 62 Flow path 70, 80, 90 Protrusions 72, 82 Groove P Powder R Circumferential direction V1, V2 Valve X Radial direction Z Vertical direction

Claims (3)

It is a vertical drop type powder heating device that heats while dropping powder.
The inlet for powder and
An outlet provided below the inlet to take out the heated powder,
A heating flow path forming portion provided between the inlet and the outlet and forming a heating flow path extending in the vertical direction,
A first heater arranged around the heating flow path forming portion is provided.
The heating flow path forming portion includes an inner wall extending in a tubular shape in the vertical direction and an outer wall extending in a tubular shape in the vertical direction at a position surrounding the inner wall at intervals from the outside, and an annular shape is formed between the inner wall and the outer wall. Form a heating channel,
The inner wall has an inclined portion extending upward at the lower end portion.
The inclined portion has an open lower end to form an opening .
A box-shaped rotating body that forms a flow path through which powder flows and rotates in the circumferential direction is provided below the inlet and above the inner wall of the heating flow path forming portion.
The rotating body has an upstream opening communicating with the inlet formed upward and a downstream opening communicating with the upstream opening laterally.
The rotating body has a plurality of blades extending radially from the center side to the outside in the internal flow path, and the plurality of blades form a plurality of flow paths , a vertical drop type powder heating device. .. The vertical drop type according to claim 1, wherein the upper end portion of the inner wall of the heating flow path forming portion has an inclined surface inclined so as to spread outward so as to spread downward, and the inclined surface is closed. Powder heating device. The vertical drop-type powder heating device according to claim 1 or 2 , further comprising a second heater inside the inner wall of the heating flow path forming portion.

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