WO2010047237A1

WO2010047237A1 - Pan coating device and pan coating method

Info

Publication number: WO2010047237A1
Application number: PCT/JP2009/067616
Authority: WO
Inventors: 靖豊伏島; 卓也中村; 敬寺田; 重実磯部
Original assignee: フロイント産業株式会社
Priority date: 2008-10-21
Filing date: 2009-10-09
Publication date: 2010-04-29
Also published as: JP2010099554A; JP5161724B2

Abstract

In a pan coating device (10) provided with a rotating drum (1) which rotates about a horizontal rotational axis line (O) and comprises a vent hole (6) in a body portion (4), a spray nozzle (81) for spraying a fine cooling mist into a housing (2) which houses the rotating drum (1) is installed. The pan coating device (10) performs a precooling step, a spraying step, a first pause step (pause 1), a second pause step (pause 2), and a drying step. In the precooling step, the spraying step, and the first pause step, the rotating drum (1) is cooled by spraying the cooling mist from the spray nozzle (81). Fine water drops with an average particle diameter of 5-100 μm inclusive are used as the cooling mist.

Description

Pan coating apparatus and pan coating method

The present invention relates to a pan-type coating apparatus that performs a coating process on tablets and powder particles, and more particularly, to a pan coating apparatus that reduces adhesion of sugar coating liquid to the inner surface of the bread during sugar coating.

Conventionally, a coating apparatus using a rotating drum is known as a manufacturing apparatus for pharmaceuticals and foods. For example, Patent Document 1 discloses a device that rotates a rotary drum having a polygonal cross section (here, an octagon) around a horizontal axis. Such a rotating drum is also called a coating pan, and a spray device for supplying a coating liquid is disposed inside the drum. The granular material thrown into the rotating drum rolls as the drum rotates. A coating liquid such as a sugar coating liquid is sprayed from the spray device onto the surface of the rolling granular material. Along with the spraying of the coating liquid, hot air and cold air are appropriately supplied and exhausted into the rotating drum, and the formation and drying of the coating layer are promoted.

When performing the sugar coating process using such a coating apparatus, first, an object to be processed (tablets, etc., hereinafter, taking up tablets as a representative) is housed in a rotating drum. Thereafter, while rotating the rotating drum, a coating liquid (sugar coating liquid) or a binder liquid is supplied into the drum and adhered to the outer periphery of the tablet. During the coating process, warm air of about 50 to 100 ° C. is appropriately fed to the tablets. With this warm air, the sugar-coating liquid is evaporated and dried on the tablet surface to form a coating layer. Then, the coating liquid is added and dried. By repeating this operation, a number of coating layers are stacked on the outer periphery of the tablet to form a sugar coating layer.

However, during the coating process, the rotating drum itself is also warmed by the warm air, so that the sugar coating liquid solidifies and adheres to the inner surface of the rotating drum. If this solidified material is peeled off from the drum inner surface and adheres to the product, minute dot-like projections or projections are generated, which causes defective products. For this reason, it is necessary to appropriately clean the inside of the rotating drum during the coating process. For example, in sugar coating, the rotating drum is stopped when the amount of sugar coating residue attached to the inner surface of the drum increases, and the attached residue is discharged out of the drum.

However, since such a cleaning operation is performed by interrupting the coating process, the processing efficiency is lowered and the number of work steps is increased. Therefore, in order to suppress the solidification / adhesion of the sugar coating liquid on the inner surface of the rotating drum, Patent Document 2 describes an apparatus in which an injection nozzle for cooling the drum is installed outside the rotating drum. The spray nozzle sprays cold water onto the rotating drum, and cools the rotating drum during the sugar coating process. Thereby, in the apparatus of patent document 2, the adhesion amount of the sugar coating residue to a drum inner surface reduces, and processing efficiency and work man-hours are improved.
Japanese Unexamined Patent Publication No. 2007-203228 JP 2004-148292 A JP 2007-160190 A

On the other hand, in recent years, since the apparatus configuration is simple and maintenance is easy, so-called jacketless type coating apparatuses have been used in which the jacket for air supply / exhaust provided on the outer periphery of the drum is eliminated. This jacketless type apparatus introduces air from the opening at the axial end of the drum. The air that enters the drum and passes through the tablet layer is discharged from a predetermined portion on the side of the drum. The straight drum portion at the center of the drum has a full punching structure formed of a perforated plate such as punching metal, and the entire circumference of the drum has a ventilation structure.

However, in such a coating apparatus equipped with a full punching type rotating drum, as in Patent Document 2, when cold water is sprayed on the outer periphery of the drum, the rotating drum has a ventilation structure. The problem of intrusion occurs. When cooling water flows into the drum, the tablet gets wet, which is not preferable for the coating process. In this respect, since the apparatus of Patent Document 2 uses a rotating drum that does not have air permeability, even if cold water is sprayed onto the outer periphery of the drum, there is no effect on the internal tablets. However, in the drum having the entire punching configuration as described above, the water inside the drum is unavoidable. For this reason, a jacketless type apparatus using a full-face punching drum has the advantage that it is simple in structure and easy to maintain, but has not been widely used in Japan.

An object of the present invention is to suppress the adhesion of sugar coatings to the inner surface of a drum during coating processing in a coating device using a rotating drum having a full-surface punching configuration, such as a jacketless type coating device, and to improve processing efficiency and man-hours. Is to improve.

A pan coating apparatus according to the present invention includes a rotary drum that is rotatably provided about a substantially horizontal rotation axis and has a vent hole in at least a part of an outer peripheral portion thereof, and a housing that houses the rotary drum. The pan coating apparatus includes a drum cooling unit that is installed in the casing and sprays a cooling medium containing fine cooling mist on the outside of the rotating drum.

In the present invention, the cooling drum containing the fine cooling mist is sprayed on the outside of the rotating drum by the drum cooling means installed in the casing to cool the rotating drum. Since the cooling mist is fine, very little moisture enters the drum due to the cooling mist, and the inside of the drum is difficult to wet even if mist spraying is performed on the rotating drum having the vent holes. For this reason, the drum can be directly cooled even in the coating apparatus using the entire punching drum. This makes it difficult for the solidified coating liquid to adhere to the inner surface of the drum during the coating process, thereby reducing the number of drum cleaning operations and improving the production efficiency.

In the pan coating apparatus, fine water droplets having an average particle diameter of 5 μm or more and 100 μm or less may be used as the cooling mist. Further, the cooling medium is sprayed by a spray gun installed in the rotary drum, and the spray area of the cooling medium in the outer peripheral portion of the rotary drum is preferably 50 mm to 400 mm in diameter per spray gun, more preferably the diameter. You may set to about 300 mm.

On the other hand, the pan coating method of the present invention is provided so as to be rotatable about a substantially horizontal rotation axis, and has a rotary drum having a vent hole in at least a part of the outer peripheral portion, a housing for housing the rotary drum, In a pan coating apparatus, which is provided in a casing and includes a drum cooling means for spraying a cooling medium containing fine cooling mist to the outside of the rotating drum, a coating liquid is supplied into the rotating drum to rotate the rotating drum. A pan coating method for performing a coating process on an object to be processed in a drum, wherein (a) the cooling medium is sprayed on the outer side of the rotating drum without supplying and exhausting air to the rotating drum to cool the rotating drum. (B) without rotating the rotating drum without supplying and exhausting the rotating drum; A spraying step of spraying a coating liquid; (c) a pause step of rotating the rotating drum without supplying and exhausting the rotating drum to spread the coating liquid on the object to be treated; and (d) a rotating drum. It has each process of the drying process which rotates the said rotating drum, supplying and exhausting, and drying and solidifying the said coating liquid on the said to-be-processed object.

In the present invention, since the spraying process is performed with the rotating drum cooled in the precooling process, the solidified coating liquid is less likely to adhere to the drum inner surface during the spraying process. Also, when these steps (a) to (d) are repeated, the rotating drum warmed in the drying step is cooled in the pre-cooling step, so that it can be transferred in a short time during the next spraying step. Processing time is reduced. Furthermore, since the rotating drum is cooled by a cooling medium containing fine cooling mist, the moisture entering the drum by the cooling mist is very little, and even if mist spraying is performed on the rotating drum having a vent, Is difficult to wet. For this reason, the drum can be directly cooled even in the coating apparatus using the entire punching drum.

In the pan coating method, in addition to the precooling step, the cooling medium may be sprayed to the outside of the rotating drum in the spraying step. Thereby, a rotating drum is cooled also during a spraying process, and solidified substance adhesion of the coating liquid at the time of a spraying process is suppressed. In addition to the precooling step, the cooling medium may be sprayed to the outside of the rotating drum also in the spraying step and the pause step. Thereby, the rotating drum is cooled during the spraying process and the pause process, and the solidified product adherence of the coating liquid during the spray process and the pause process is suppressed. Note that if the cooling medium is sprayed when dry air is not ventilated and the inside of the rotating drum is in a high humidity state as in the spraying process or the pause process, even if moisture enters the drum due to mist spraying. There is almost no impact.

In the pan coating method, fine water droplets having an average particle diameter of 5 μm or more and 100 μm or less may be used as the cooling mist. In addition, the spray area of the cooling medium in the outer peripheral portion of the rotating drum may preferably be set to a diameter of 50 mm to 400 mm, more preferably about 300 mm per drum cooling means.

According to the pan coating apparatus of the present invention, the rotating drum is accommodated in the pan coating apparatus provided with a rotating drum that is provided so as to be rotatable about a substantially horizontal rotation axis and has a vent hole in at least a part of the outer peripheral portion. Since the drum cooling means for spraying the cooling medium containing the fine cooling mist on the outside of the rotating drum is installed in the casing, the rotating drum can be directly cooled by the cooling mist. This makes it difficult for the solidified coating liquid to adhere to the inner surface of the drum during the coating process, thereby reducing the number of drum cleaning operations and improving the production efficiency. In addition, since the cooling mist is fine, very little moisture enters the drum due to the cooling mist. Therefore, even if mist spraying is performed on a rotating drum having a vent hole, the inside of the drum is difficult to wet, and the drum can be directly cooled even in a coating apparatus using a full-punch type rotating drum.

According to the pan coating method of the present invention, a rotating drum is accommodated in a pan coating apparatus provided with a rotating drum that is provided to be rotatable about a substantially horizontal rotation axis and has a vent hole in at least a part of the outer peripheral portion. A drum cooling means for spraying a cooling medium containing fine cooling mist on the outside of the rotating drum, and a pre-cooling step for spraying the cooling medium on the rotating drum without supplying and exhausting in the apparatus; A spraying process for spraying the coating liquid onto the workpiece while rotating the drum without supplying / exhausting the rotating drum, a pause process for rotating the drum without supplying / exhausting the rotating drum, and a supply of the rotating drum Since the drying process of rotating the rotating drum while exhausting is performed, the rotating drum is cooled in the precooling process. Can implement play process, solidification of the coating liquid can be prevented from adhering to the inner surface of the drum at the time of spraying process. Also, when these steps are repeated, the rotating drum heated in the drying step is cooled in the pre-cooling step, so that it can be transferred in a short time during the next spraying step, and the processing time is shortened. The Furthermore, since the rotating drum is cooled with a cooling medium containing fine cooling mist, the moisture entering the drum by the cooling mist is very small. Therefore, even if mist spraying is performed on a rotating drum having a vent hole, the inside of the drum is difficult to wet, and the drum can be directly cooled even in a coating apparatus using a full-punch type rotating drum.

It is a right view which shows the structure of the pan coating apparatus which is one Example of this invention. It is a front view of the pan coating apparatus of FIG. It is a top view (top view) of the pan coating apparatus of FIG. (A) is a side view of a rotating drum, (b) is explanatory drawing which shows the structure of the three-dimensional ventilation baffle installed in the rotating drum. It is a top view which shows the state which opened the chamber door. It is a front view of the state which opened the chamber door. (A) is a front view of a wind direction board, (b) is the sectional drawing. It is explanatory drawing which shows operation | movement of a multifunction unit. It is a front view of a multifunction unit. It is explanatory drawing which shows the structure of the vertical movement mechanism of a multifunction unit. It is a front view of a manual multi-move mechanism. It is a side view of the multi-moving mechanism of FIG. It is a side view of the multi move mechanism by a motor drive. (A) is explanatory drawing which shows the sugar-coating process process in the said coating apparatus, (b) is a table | surface which shows the presence or absence of the air supply / exhaust operation, transpiration mist operation, and mist cooling operation in each process of (a).

DESCRIPTION OF SYMBOLS 1 Rotating drum 2 Housing | casing 2a Front wall 2b Upper surface 3 Tablet (to-be-processed object) 4 Body part 5 Conical part 6 Vent hole 7 Front opening part 8 End plate 9 Rotating shaft 10 Pan coating apparatus 11 Chamber door 12 Hinge 13 Air supply chamber 13a Air supply chamber front inner wall 14 Monitoring window 15 Inspection door 16 Grip bar 17 Product discharge port 18 Air supply hole 19 Air supply duct 21 Air supply port 22 Airflow direction plate 23 Frame body 24 Louver 25 Front cover 26 Baffle 27 Vent hole 28 Baffle mounting hole 29 Drum chamber 30 Sink 31 Spray gun 31a Spray gun 31b for sugar coating 31b Spray gun 32 for film coating Bifunctional unit 33 Support holder 34a Hinge 34b Hinge 35 Support arm 35a Upper tube portion 35b Lower tube portion 35c Connection port 36 Unit cover 37 Arm guide 38 Bracket 39 Air cylinder 40 Bracket 41 Multi-moving mechanism 41a Vertical movement mechanism 41b Left-right movement mechanism 42 Multi-moving mechanism 43 Bracket 44 Vertical movement base 45 Shaft holder 46a, 46b Guide block 47 Nut block 48 Guide rod 49 Left / right movement base 51 Shaft holder 52 Screw rod 53 Screw holder 54 Screw holder 55a, 55b Gear 56 Vertical movement knob 57 Shaft holder 58a, 58b Guide block 59 Nut Block 60 Guide rod 61 Unit base 62 Shaft holder 63 Screw rod 64 Screw holder 65 Screw holder 66a, 66b Gear 67 Left / right movement knob 68 Vertical movement motor 69 Left / right movement motor 71 Exhaust duct 72 Seal duct 73 Exhaust port 74 Upper duct 75 Evaporation mist exhaust port 76 Transpiration mist inlet 81 Spray nozzle 81a Body spray nozzle 81b Conical spray nozzle 82 Control panel H Upper position L Lower position O Rotation axis θ Angle

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a right side view showing a configuration of a pan coating apparatus 10 (hereinafter abbreviated as a coating apparatus 10) according to an embodiment of the present invention, FIG. 2 is a front view thereof, and FIG. 3 is a plan view (top view). is there. The apparatus shown in FIG. 1 is a jacketless type coating apparatus using a so-called full punching type rotating drum. In the coating apparatus 10, an object to be processed such as a tablet is accommodated in a rotating drum 1 (coating pan, hereinafter abbreviated as drum) 1. And a coating process of the to-be-processed object is performed by spraying a coating liquid on the to-be-processed object in a drum.

As shown in FIGS. 1 to 4, in the coating apparatus 10, the drum 1 is rotatably installed at the center of the casing 2. The drum 1 rotates about a substantially horizontal rotation axis O. An object to be processed such as gum, chocolate, or tablet is placed inside the drum 1. In the following, an embodiment of the present invention will be described by taking a tablet as a representative of the object to be processed and taking a coating process for the tablet 3 placed in the drum 1 as an example.

Generally, a drum (tilt pan) whose rotation axis is inclined with respect to the horizontal has a larger amount of tablets and a larger processing amount than a drum that rotates around the horizontal axis. On the other hand, in the inclined drum, since the tablets in the drum are classified by gravity, the coating varies between products, which is not suitable for precise coating processing. Moreover, although the filling rate of the tablet in a drum becomes high, the layer of the accommodated tablet becomes high and the tablet's own weight also becomes large. For this reason, the damage given to a raw material tablet etc. also becomes large. In this respect, the horizontal rotation type drum has less of these problems and is suitable for high-quality coating processing.

FIG. 4A is a side view of the drum 1. The drum 1 includes a cylindrical body portion 4 and a truncated cone-shaped conical portion 5 formed at both ends of the body portion 4. The trunk | drum 4 is formed with the perforated plate made from stainless steel. The outer periphery of the trunk portion 4 can be ventilated by a large number of vent holes 6. The conical part 5 is formed of a stainless steel plate material having no holes. A front opening 7 is formed on one end side of the conical portion 5. The other end side is closed by an end plate 8, and a rotating shaft 9 is attached.

Inside the drum 1, a baffle 26 is installed in order to disturb the tumbling flow of the tablet and increase the mixing and stirring efficiency. FIG. 4B is an explanatory diagram showing the configuration of the baffle 26. The baffle 26 is also formed of a stainless perforated plate having a large number of air holes 27. As shown in FIG. 4B, the baffle 26 is formed in a mountain shape with a substantially triangular cross section. The baffle 26 is fixed to a baffle mounting hole 28 formed in the trunk portion 4. The baffle mounting hole 28 is a rectangular opening. The bottom edge of the baffle 26 is welded to the periphery of the baffle mounting hole 28. The baffle 26 is disposed so as to protrude into the drum 1, whereby a breathable three-dimensional baffle is erected inside the drum 1.

Thus, when the baffle 26 itself has a three-dimensional ventilation structure, not only the mixing and stirring of the tablet can be promoted, but also the loss of ventilation of the processing gas can be eliminated. That is, in the case of a baffle that does not have a ventilation structure, when the processing gas is exhausted from the inside of the drum, the baffle portion may become a barrier to prevent ventilation, and pulsation may occur in the exhaust. In that regard, in the coating apparatus 10, the baffle 26 has a ventilation structure, so that air circulation is not hindered and exhaust pulsation can be suppressed. Therefore, the effect of reducing the pulsation of the ventilation air by the jacketless structure can be further improved, and the coating process can be performed without disturbing the spray pattern. Further, the baffle 26 increases the heat radiation area of the drum 1, and the baffle 26 and the body 4 are uniformly cooled by mist cooling described later, so that the drum cooling efficiency is also improved.

A drum rotation mechanism (not shown) using an electric drum drive motor is disposed on the right side of the drum 1 in FIG. As described above, the rotary shaft 9 is fixed to the right end side (the other end side) of the drum 1. A sprocket (not shown) is attached to the rotary shaft 9. The sprocket is connected to a motor-side sprocket installed in the housing 2 via a chain. When the motor is rotated, the drum 1 is chain-driven along with the rotation, and rotates about the rotation axis O. 1 and 4, the left end side of the drum 1 is supported by a roller (not shown).

The housing 2 has a double structure in which a drum chamber 29 for accommodating the drum 1 is provided. A sink 30 is provided below the drum chamber 29. The sink 30 has a watertight structure with a drain port (not shown) at the bottom, and can store a cleaning liquid such as water therein. When cleaning the coating apparatus 10, the cleaning liquid is stored in the sink 30, where the drum 1 is rotated and the inside and outside of the drum are stored and washed. After the drum cleaning, the cleaning liquid is discharged from the drain port described above, and rinsing or drying is performed as appropriate.

The front surface of the housing 2 (left side in FIG. 1, see FIG. 2) has a three-part structure. A chamber door 11 is disposed in the center of the front of the housing. The chamber door 11 is a rectangular parallelepiped box-shaped member of about 900 mm × 1100 mm × 200 mm. The chamber door 11 is supported by the housing 2 by a hinge 12 so as to be freely opened and closed. The chamber door 11 has a box shape in which the surface on the front wall 2a side of the housing 2 is opened. An air supply chamber 13 is formed inside the chamber door 11. The air supply chamber 13 is disposed in front of the front opening 7 of the drum 1. The cross-sectional area facing the front opening 7 of the air supply chamber 13 is about 5 times (preferably twice or more, preferably about 8 times the area of the front opening 7 (inner diameter: about 500 mm), considering the case size. Is preferable). The front side of the chamber door 11 is a curved surface, and accordingly, the front inner wall 13a of the air supply chamber 13 is also a curved surface. Thereby, while creating the external appearance with the design characteristic, the volume in the air supply chamber 13 is expanded.

Further, an inspection door 15 provided with a monitoring window 14 in the center is attached to the front of the chamber door 11. On both sides of the inspection door 15, grip bars 16 extending in the vertical direction are attached. Further, a product discharge port 17 for taking out the product after the completion of processing is attached to the lower portion of the chamber door 11. In the coating apparatus 10, the grip bars 16 arranged on both sides of the inspection door 15 constitute an H-shaped design that does not exist in the conventional coating apparatus on the front surface, and design accents are formed (see FIG. 2).

The chamber door 11 is attached to the housing 2 by opening right. The chamber door 11 has a grip bar 16 on the front surface of the chamber and can be opened from the front side of the apparatus. FIG. 5 is a plan view showing a state in which the chamber door 11 is opened, and FIG. 6 is a front view of the coating apparatus 10 in a state in which the chamber door is opened. As shown in FIG. 6, when the chamber door 11 is opened, the housing front wall 2 a is exposed and the front opening 7 at the end of the drum 1 is opened. An air supply hole 18 is further provided above the front opening 7 of the housing front wall 2a. The coating apparatus 10 employs an internal air supply structure, and the air supply hole 18 communicates with an air supply port 21 provided in the upper surface 2b of the housing via an air supply duct 19 disposed in the housing 2. is doing. As shown in FIG. 1, in the coating apparatus 10, since the air supply duct 19 is bent and disposed in an empty space formed above the drum conical portion 5 in the housing 2, the apparatus is downsized. The air flow rate is lowered by the bent duct.

A wind direction plate 22 is attached to the front surface of the air supply hole 18. FIG. 7A is a front view of the wind direction plate 22, and FIG. The wind direction plate 22 is attached to the air supply hole 18 with the right side of FIG. As shown in FIG. 7A, the wind direction plate 22 has a cylindrical frame body 23 (for example, an inner diameter of 200 mm). A plurality of louvers 24 (for example, a width of 30 mm) are fixed to the inside of the frame body 23 by welding. The louver 24 is attached with an inclination of 60 °, for example, with respect to the end face of the frame. The air (dry air) supplied from the air supply port 21 is rectified downward by the wind direction plate 22 and discharged from the air supply hole 18.

In the coating apparatus 10, when the chamber door 11 is closed, the front opening 7 of the drum 1 faces and communicates with the air supply chamber 13. Therefore, the air supplied to the air supply port 21 flows into the air supply chamber 13 while being rectified by the wind direction plate 22. Then, the air is supplied from the air supply chamber 13 into the drum 1 through the front opening 7. That is, the coating apparatus 10 supplies air to the drum 1 from the air supply duct 19 through the large volume air supply chamber 13. For this reason, the flow rate of the air supplied into the drum can be sufficiently lowered and stabilized even when a large amount of air is ventilated.

Thus, the air supply chamber 13 acts as a buffer portion (buffer) for the air supplied from the air supply duct 19. That is, the air supply chamber 13 reduces the air flow rate and also makes the flow rate in the front opening 7 uniform over the entire cross section. In the coating apparatus 10, since the front inner wall 13 a of the air supply chamber 13 is curved, the air supplied from the air supply duct 19 into the chamber hits the curved front inner wall 13 a facing the air supply hole 18 and is diffused. It becomes a mild airflow. In addition, in the apparatus, since the airflow direction plate 22 is attached to the air supply hole 18, the flow velocity is suppressed and the flow is adjusted even when it flows into the air supply chamber 13. For this reason, the buffer effect by the air supply chamber 13 is further enhanced. Therefore, in the coating apparatus 10, the air supply is milder than that in the conventional apparatus, and air is supplied to the tablet at a uniform flow rate and flow rate, and is exhausted.

Here, as in a conventional coating apparatus, when air supply is performed by connecting an air supply duct to the drum opening, the flow rate of air supplied into the drum becomes non-uniform. If the supply air is disturbed in the coating apparatus, the flow of the spray mist of the coating liquid is disturbed due to the uneven distribution of the supply air. When the spray mist is disturbed, not only can the tablets be sprayed uniformly, but also the spray mist dries before reaching the tablets, and the dry mist adheres to the drum and causes dirt. In order to sufficiently reduce and stabilize the air flow rate, it is necessary to provide a straight body portion that is long in the axial direction at the drum opening. When the straight body is long, the distance from the mouth of the drum to the product layer becomes long, workability is remarkably deteriorated, and the apparatus itself is enlarged.

In that respect, the coating apparatus 10 can perform the coating process without disturbing the spray pattern in the drum due to the stability of the airflow. For this reason, uneven coating is reduced and product quality is improved. Moreover, scattering of coating dust is reduced, and the number of drum cleaning steps can be reduced. Further, since a long straight body portion for stabilizing the airflow is unnecessary, the distance from the mouth of the drum (front opening 7) to the product layer can be shortened, workability is improved, and the apparatus is downsized. . In addition, by using the chamber door 11 having a large projected area, the depth of the chamber door 11 itself can be suppressed. Therefore, when the inspection door 15 is opened, it is possible to design such that the front opening 7 comes close immediately, and the inspection work is facilitated.

Further, as shown in FIGS. 5 and 6, a spray gun 31 for spraying the coating liquid is inserted into the drum from the front opening 7 of the drum 1 on the front wall 2a of the casing. The spray gun 31 is attached to a multi-function unit 32 disposed on the front surface of the housing 2. The spray gun 31 can be taken in and out of the drum from the front side of the apparatus by a multi-function unit 32. The multifunction unit 32 includes a support arm 35 that can move freely in an oblique 45 ° direction. A support holder 33 to which a spray gun 31 is attached is attached to the support arm 35. A sugar coating coating spray gun 31a and a film coating spray gun 31b are attached to the support holder 33. That is, the spray gun 31 corresponds to a plurality of types of coating processes in one unit.

In general, when a sugar coating treatment is performed, the sugar coating is often performed after undercoating by film coating. In that case, in the conventional coating apparatus, after performing film coating, the spray gun is replaced for sugar coating. Therefore, there is a problem that time for parts replacement is required and time loss occurs. In that respect, in the coating apparatus 10, since the spray gun 31a for sugar coating and the spray gun 31b for film coating are attached to the multi-function unit 32, the undercoating can be performed without performing the spray gun replacement work. Sugar coating can be performed continuously. For this reason, the number of man-hours required for replacement work can be reduced, work time can be shortened and labor can be saved, productivity can be improved, and efficient coating processing can be performed.

As described above, the spray gun 31 is attached to the support holder 33. The support holder 33 is connected to the support arm 35 by a hinge 34a so as to be relatively rotatable. A lock mechanism (not shown) is attached to the hinge 34a. The hinge 34a portion can be arbitrarily set in a rotatable state and a non-rotatable state by a pin or the like (not shown). The support arm 35 is attached to the unit cover 36. At the lower end of the unit cover 36, the lower end portion of the support arm 35 opens as a connection port 35c.

The unit cover 36 is located on the left side of the front of the housing divided into three. When the unit cover 36 is closed, the multifunction unit 32 is disposed on the front surface of the housing 2. In the multi-function unit 32, hoses for a spray gun are accommodated. In the coating apparatus 10, unlike the conventional apparatus, piping is not exposed on the front or side of the apparatus, and the appearance of the apparatus can be summarized in a clean form. A front cover 25 is also attached to the right side of the front of the housing. That is, the front surface of the housing 2 has a three-part configuration in which the monitoring window 14 is arranged in the center.

The support holder 33 and the support arm 35 are formed of a hollow metal pipe (for example, a diameter of 50 mm). A hose (not shown) for supplying a coating liquid and spray air to each spray gun 31 is accommodated inside the support holder 33 and the like. A maximum of five hoses (spray air, pattern air, cylinder air (needle valve), liquid (going), and liquid (returning)) are connected to one spray gun. For this reason, the total of three spray guns is 15 at the maximum. For guns of the same type (for example, for sugar coating), pipes are appropriately connected by branching common pipes to each gun, using common spray air and pattern air, or omitting liquid return pipes. It is also possible to reduce the number.

The hose connected to the spray gun 31 is pulled out from the connection port 35c to the outside of the apparatus. That is, in the coating apparatus 10, the liquid hose and the air hose are concealed pipes, and these hoses are not exposed to the outside. For this reason, the contamination of the parts is small, the maintainability is improved, and the coating liquid and air are hardly affected by the temperature in the drum, and the coating quality is also improved.

The unit cover 36 is attached to the housing 2 by a hinge 34b so as to be freely opened and closed. FIG. 8 is an explanatory diagram showing the operation of the multifunction unit 32, and FIG. 9 is a front view of the multifunction unit 32. As shown in FIG. 8, in this embodiment, the multifunction unit 32 and the support holder 33 are a two-joint link mechanism connected by a hinge 34b. That is, in the coating apparatus 10, the spray gun 31 is installed in the drum 1 so as to be freely inserted and removed by appropriately bending the support arm 35 and the support holder 33 of the multifunction unit 32.

If the support gun 33 and the support arm 35 are not bent and the spray gun 31 is moved in and out of the drum while the both are at right angles, the diameter of the front opening 7 must be increased. In addition, an area for moving more spray guns must be secured in front of the apparatus. On the other hand, in the coating apparatus 10, the spray gun 31 can be moved into and out of the drum while suppressing the radius of rotation by folding both of the support holder 33 and the support arm 35 so that the angle θ between the support holder 33 and the support arm 35 is small. it can. Therefore, the diameter of the front opening 7 and the area for moving the spray gun can be reduced, and the apparatus is made compact.

As shown in FIG. 9, the multi-function unit 32 is arranged so as to move up and down in an oblique 45 ° direction (substantially perpendicular to the tablet flow surface). That is, in the coating apparatus 10, the position of the spray gun in the drum can be changed as appropriate. FIG. 10 is an explanatory diagram showing the configuration of the vertical movement mechanism of the multifunction unit 32. As shown in FIG. 10, the support arm 35 has a double tube structure. The support arm 35 is connected to the upper tube portion 35 a and the lower tube portion 35 b in the unit cover 36. The upper tube portion 35 a is slidably inserted into an arm guide 37 fixed to the unit cover 36. The upper pipe portion 35 a is connected to the air cylinder 39 via a bracket 38. The lower pipe portion 35 b is fixed to the unit cover 36 by a bracket 40.

When the air cylinder 39 is operated, the upper pipe portion 35a moves along the axial direction. Then, the multifunction unit 32 moves about 150 mm between the lower position L and the upper position H shown in FIG. As a driving device for the upper pipe portion 35a, a hydraulic cylinder that is an actuator using the same fluid pressure may be used instead of the air cylinder 39. In addition, an electric motor can be used as the driving device.

By the way, in the coating apparatus 10, as shown in FIG. 10, the multi-function unit 32 is configured to move obliquely at 45 °, but this may be a multi-moving mechanism that can move in the vertical and horizontal directions. That is, the spray gun 31 may be moved to an arbitrary position in the vertical direction (Y direction: vertical direction) and the horizontal direction (X direction: horizontal direction). FIGS. 11 to 13 are modifications of the multi-function unit using such a multi-moving mechanism. 11 is a front view of the manual multi-moving mechanism 41, FIG. 12 is a side view of FIG. 11, and FIG. 13 is a side view of the multi-moving mechanism 42 driven by a motor. Note that. The multi-move mechanism 41 has a specification of being arranged on the right side of the front surface of the housing as shown by a one-dot chain line in FIG. 9, but it is of course possible to arrange it on the left side. In the multi-function unit shown in FIGS. 11 to 13, the support holder 33 is fixed to the support arm 35. Accordingly, the spray gun 31 is inserted into the drum 1 and taken out from the drum 1 without bending the holder and the arm.

The multi-moving mechanism 41 includes a vertical movement mechanism 41a and a horizontal movement mechanism 41b. As shown in FIGS. 11 and 12, the upper tube portion 35 a of the support arm 35 is fixed to the vertical movement base 44 on the vertical movement mechanism 41 a side by a bracket 43. A shaft holder 45, guide blocks 46 a and 46 b, and a nut block 47 are attached to the vertical movement base 44. One end side of the guide rod 48 is fixed to the shaft holder 45. The guide rod 48 is supported by

guide blocks

46a and 46b so as to be movable in the axial direction. The other end side of the guide rod 48 is fixed to a shaft holder 51 attached to the left and right moving base 49.

A screw rod 52 using a trapezoidal screw is screwed onto the nut block 47. One end side of the screw rod 52 is supported by a screw holder 53. The screw holder 53 is attached to the left / right moving base 49 of the left / right moving mechanism 41b. The other end side of the screw rod 52 is fixed to the screw holder 54. The screw holder 54 is also attached to the left and right moving base 49. One end of the screw rod 52 is connected to a vertical movement knob 56 via

gears

55a and 55b. When the vertical movement knob 56 is rotated, the screw rod 52 is rotated via the

gears

55a and 55b, and the nut block 47 is moved in the axial direction. Thereby, the vertical movement base 44 to which the nut block 47 is fixed moves up and down, and the upper pipe portion 35a moves up and down.

Further, a shaft holder 57, guide blocks 58a and 58b, and a nut block 59 are attached to the left and right moving base 49. One end side of the guide rod 60 is fixed to the shaft holder 57. The guide rod 60 is supported by

guide blocks

58a and 58b so as to be movable in the axial direction. The other end side of the guide rod 60 is fixed to the shaft holder 62. The shaft holder 62 is attached to the unit base 61. The unit base 61 is fixed to the housing 2.

Thread screw rod 63 using trapezoidal screws is screwed onto the nut block 59. One end side of the screw rod 63 is fixed to the screw holder 64. The screw holder 64 is attached to the left and right moving base 49. The other end side of the screw rod 63 is fixed to the screw holder 65. The screw holder 65 is attached to the unit base 61. One end side of the screw rod 63 is connected to a left and right movement knob 67 via

gears

66a and 66b, similarly to the vertical movement mechanism 41a. When the left / right moving knob 67 is rotated, the screw rod 63 is rotated via the gear, and the nut block 59 is moved in the axial direction. As a result, the left-right motion base 49 to which the nut block 59 is fixed moves to the left and right, and the upper tube portion 35a moves to the left-right direction. That is, the upper pipe portion 35a can be moved in any direction, up, down, left, and right by appropriately moving the vertical movement knob 56 and the horizontal movement knob 67.

As described above, the multi-function unit 32 is configured to be freely movable in the horizontal direction and the vertical direction, so that the degree of freedom of adjustment of the spray gun position can be expanded and the installation position of the spray gun 31 can be set finely. It becomes possible. Therefore, it is possible to perform the coating process while always setting the spray gun at the optimum position. For this reason, as compared with a coating apparatus in which the spray gun can move only in one direction, control that keeps the distance between the tablet surface and the spray gun 31 constant can be performed easily and accurately. This makes it possible to continuously perform the coating process without stopping the apparatus, thereby improving the coating process efficiency and reducing the production cost.

Also, the above operation may be performed electrically. In the multi-moving mechanism 42, a vertical movement motor 68 and a left / right movement motor 69 are provided in place of the vertical movement knob 56 and the left / right movement knob 67. The multi-moving mechanism 42 is slightly different from the multi-moving mechanism 41 of FIGS. 11 and 12 due to the arrangement of the

motors

68 and 69, but the basic mechanism and operation are the same as those of the multi-moving mechanism 41. is there. Therefore, in the description of the multi-moving mechanism 42, the same reference numerals are given to the same members / parts as those of the multi-moving mechanism 41, and the detailed description thereof is omitted.

The casing 2 is also connected with an exhaust duct 71 for discharging the air supplied to the drum 1. A seal duct 72 and an upper duct 74 are installed in the housing 2. The seal duct 72 is in sliding contact with the body 4 of the drum 1. The upper duct 74 is connected to the seal duct 72 and extends toward the exhaust port 73. The exhaust duct 71 is connected to the exhaust port 73. Air supplied from the chamber door 11 is discharged from the drum 1 to the seal duct 72, and is discharged outside the apparatus through the upper duct 74 and the exhaust duct 71.

On the other hand, if the coating liquid or the like is sprayed into the drum 1 with the spray gun 31 and the exhaust is not performed at that time, the humidity in the drum becomes 100%, and the inside of the drum is in a state of fog. At this time, in order to exhaust the excess humidity in the drum without affecting the coating process, the casing 2 is provided with a transpiration mist exhaust port 75 separately from the exhaust system. The transpiration mist exhaust port 75 opens to the internal space of the housing 2 and is connected to the exhaust duct 71.

When the transpiration mist exhaust is performed, the internal space of the housing 2 that is a sealed space becomes negative pressure, and therefore, a transpiration mist intake port 76 is provided to supplement the exhausted amount. A duct (not shown) that connects the internal space of the housing and the outside of the housing is attached to the air inlet 76. A damper that controls opening and closing of the duct is installed in the duct. When exhausting transpiration mist, the damper is opened to take in external air. Thereby, the inside of the drum 1 is weakly sucked by the ventilation system thinner than the exhaust system, and the transpiration mist in the drum 1 is discharged out of the apparatus.

The coating apparatus 10 is further provided with a spray nozzle 81 for cooling the drum in the housing 2. From the spray nozzle 81, a cooling medium such as humidified air containing fine mist is sprayed on the outer periphery of the drum 1. The drum 1 is cooled by the heat of vaporization of the cooling medium. Conventionally, it has been known to cool a drum without air holes by water spray. However, spray cooling of a full-face punching drum used in a jacketless type coating apparatus has been considered to cause quality problems because the tablet in the drum gets wet. On the other hand, this apparatus uses a very fine mist and considers the timing of spraying, thereby overturning the common sense and enabling the cooling of the drum 1 having a vent hole. For this reason, it was possible to cool the entire punching drum, which was impossible in the past, and to improve the performance of the jacketless type apparatus.

A plurality of spray nozzles 81 as described above are provided in the housing 2. In the coating apparatus 10, the spray nozzle 81 is disposed at a position where spraying is possible on both the body 4 and the conical part 5 (for body: 81a, conical part 81b). The distance between the spray nozzle 81 and the drum 1 is set to about 200 mm to 250 mm. The spread of the spray pattern (spray area) is preferably 50 to 400 mm in diameter per spray nozzle 81 on the outer peripheral surface of the drum. For example, in the coating apparatus 10, the diameter is about 300 mm. The spray nozzle 81 is preferably attached at a position where the spray hits the body 4 from the tangential direction in order to suppress mist intrusion into the drum 1.

As the spray nozzle 81, an internal mixing type two-fluid nozzle is used, and fine mist of the coolant is sprayed onto the drum 1 from the nozzle. In the coating apparatus 10, water (possible at room temperature) is used as the coolant. In the spray nozzle 81, water and compressed air are mixed in the nozzle, and a cooling medium containing cooling mist (water mist) that is very fine water droplets is generated. The average particle size of the cooling mist is preferably 5 μm to 100 μm. However, if it exceeds 50 μm, the evaporation of mist becomes somewhat slow, and the inside of the drum 1 becomes easy to get wet. Further, an ultrafine mist such as a so-called dry fog having an average particle size of 10 μm or less, preferably about 5 to 8 μm can be used. Also in this case, the spread of the spray pattern is set to a diameter of about 50 mm to 400 mm, preferably about 300 mm, per spray nozzle 81, but is preferably wider than the case where the diameter exceeds 10 μm.

That is, as the drum cooling method in the coating apparatus 10, various spray forms such as spraying with a fine mist of 10 μm to 100 μm or a dry fog spray of 10 μm or less can be appropriately employed. It should be noted that the mist diameter may be different between the conical part 5 having no air holes and the perimeter punching body part 4. For example, a relatively large mist of more than 10 μm to 50 μm may be sprayed on the conical part 5 having no air permeability, and an ultrafine 5 to 8 μm mist may be sprayed on the body part 4 having a full punching structure.

Such cooling mist is sprayed evenly from the spray nozzle 81 to the entire outside of the drum 1. Thereby, the drum section 4 and the conical section 5 of the drum 1 are cooled by the heat of vaporization of the attached cooling mist. At that time, since the sprayed cooling mist has a very small particle size, it quickly evaporates after adhering to the drum 1. For this reason, even if the cooling mist is sprayed onto the drum 1 having the air holes, the moisture evaporates on the drum surface and hardly enters the drum, and the drum can be cooled in a dry environment.

Next, the coating process using such a coating apparatus will be described taking the production of sugar-coated tablets as an example. Here, first, as a tablet 3 to be coated, a tablet such as a lactose tablet (for example, a diameter of 8 mm, 200 mg / T) is put into the drum 1. In the coating apparatus 10, the tablet 3 is introduced from the front opening 7 with the chamber door 11 opened. At that time, since the front opening 7 of the coating apparatus 10 comes close to the operator, it is very easy to put tablets. Note that the multifunction unit 32 is moved out of the drum 1 when the tablets are inserted. After the predetermined amount of tablets 3 is charged, the multifunction unit 32 is operated to set the spray gun 31 in the drum 1. Thereafter, the chamber door 11 is closed, the drum drive motor is operated, and the drum 1 is rotated.

The tablet 3 in the drum is sprayed with the coating liquid (sugar coating liquid) from the spray gun 31 while rotating the drum 1. The coating liquid contains a coating substance, a binder, a solvent, and the like, and is sprayed from the spray gun 31 at a predetermined pressure. FIG. 14 (a) is an explanatory view showing a sugar coating process in the coating apparatus, and FIG. 14 (b) shows the presence / absence of a supply / exhaust operation, a transpiration mist operation, and a mist cooling operation in each step of FIG. 14 (a). It is a list shown.

In the conventional coating process, usually, three processes of “spray” → “pause 1” (first pause process) → “drying” are repeated. Also, depending on the coating solution and other various conditions, “pause 2” (second pause process) is usually performed between “pause 1” and “drying” processes to form 4 processes. “Spray” is a step of spraying the coating liquid while rotating the drum 1 without supplying and exhausting air (for example, about 8 rpm, hereinafter, the indication of illustration is omitted for numerical examples). “Pause 1” is a kneading process in which the drum 1 is rotated without supplying air and the coating liquid is spread on the tablet. “Pause 2” is a process in which the drum 1 is rotated while exhausting only to reduce the humidity in the drum before the drying process. In the

pause

1 and 2 steps, the coating liquid is not sprayed. “Drying” is a process of supplying hot air to the drum 1 without spraying the coating liquid (70 ° C., 12 m ³ / min) to dry and solidify the coating liquid on the tablet.

On the other hand, in the coating process in the apparatus, as shown in FIG. 14A, a pre-cooling process is added before the “spraying” process in the conventional processing process. This pre-cooling step is a step of spraying a cooling medium containing cooling mist from the spray nozzle 81 to cool the drum 1 with mist. Further, the cooling mist spraying by the spray nozzle 81 is performed through three steps of “pre-cooling” → “spray” → “pause 1”. That is, as shown in FIGS. 14A and 14B, prior to “spray”, “pre-cooling” is performed (30 seconds) in which cooling mist spraying is performed without air supply and exhaust. Note that the processing contents in the steps of “spray”, “pose 1”, “pose 2”, and “dry” in FIG. 14A are the same as described above.

After that, “spray” (2 minutes) and “pause 1” (first pause process: 3.5 to 4 minutes) are performed while continuing cooling mist spraying. The cooling mist spray may be appropriately terminated in the middle of “pause 1” depending on the processing status. In the spraying process (60 ° C., 340 to 900 mL / time), the sugar coating liquid is sprayed from the spray gun 31 onto the tablets. At that time, the position of the spray gun 31 is adjusted to an optimum position by the multi-function unit 32 according to the position of the tablet surface. As described above, since the spray gun 31 can move in an oblique 45 ° direction, the spray position with respect to the tablet flow surface can be kept constant. Therefore, the tablet coating conditions can be adjusted to a constant or desired form. In particular, when the multi-moving mechanism 41 is employed, the spray gun 31 has a high degree of freedom of movement and can flexibly cope with various coating conditions.

After completion of “pose 1”, “pause 2” (second pause process: 0.5 minutes) and “dry” (4.5 minutes) are performed. Then, as shown in FIG. 14A, this set is repeated a plurality of times (about 20 to 30 times) so as to return to “pre-cooling” after “drying”. At that time, if the spraying process is performed immediately after the drying process, the spraying is performed with the drum 1 being heated, and sugar coating residue is easily generated, which is not preferable as a coating environment. In this regard, in the coating process, “pre-cooling” is performed after the drying process, and the drum 1 is mist-cooled. Therefore, during the spraying process, the drum 1 is in a cold state, and problems such as sugar coating residue are less likely to occur. In addition, since the drum 1 is cooled in a short time, it is not necessary to wait for the drum 1 to cool, and the processing time is shortened.

In the three steps of “pre-cooling” → “spray” → “pause 1”, the cooling mist continues to be sprayed onto the drum 1, but very little water enters the drum 1 due to the fine mist. Further, after the “pose 1” step, a “drying” step is always performed. For this reason, the water | moisture content of the tablet in a process is not different from the conventional coating process. Also in the experiments by the inventors, the moisture content of the tablet during the drying process and the moisture content of the final tablet could be maintained at the same level as the conventional method. Furthermore, since the cooling mist is sprayed onto the drum 1 in a process in which dry air (warm air) is not vented, the drum wall surface can be cooled in a short time, and the cooling processing efficiency is high. In addition, when the mist is cooled, the baffle 26 together with the body 4 is also cooled by the cooling mist. For this reason, the heat radiation area increasing effect by the baffle 26 can be further enhanced, and the drum 1 can be efficiently cooled.

In addition, although it has been stated that the amount of moisture entering the drum 1 by the cooling mist is very small, the moisture intrusion into the drum 1 is still completely zero as long as the mist is sprayed. Further, since “exhaust” is performed in “drying”, the cooling mist easily enters the drum 1 due to the exhaust. Therefore, in the coating apparatus 10, for safety reasons, even if the cooling mist enters the drum 1, the cooling mist spraying is performed in a process that hardly affects the cooling mist. That is, the cooling mist spray is performed by “pre-cooling” in which the inside of the drum 1 will be wet, and “spray” and “pose 1” that are wet, and the mist is cooled in a wet environment. Thereby, the drum 1 can be cooled by the cooling mist without causing the intrusion of moisture into the drum.

As described above, the coating apparatus 10 is an apparatus using a horizontal rotation type full-face punching drum, but the outer periphery of the drum 1 with which the tablet contacts is directly cooled by the fine cooling mist. For this reason, solidification and adhesion of the sugar coating liquid to the inner surface of the drum can be suppressed, and defective products due to separation and adhesion of the solidified product can be reduced. Therefore, the generation of minute point-like protrusions of the sugar-coated tablet can be greatly reduced, and the inventors' experiments have been able to suppress the occurrence of point-like protrusions to almost none. Moreover, since the horizontal rotation type drum is used, damage to the raw material tablets can be suppressed, and the defective product generation rate is reduced in this respect as well.

Furthermore, since the adhesion of sugar coating residue to the inner surface of the drum is suppressed, the number of cleanings inside the drum can be reduced, and the processing efficiency and work man-hours are improved. As a result, the spread of a jacketless type coating apparatus having a simple structure and easy maintenance is also promoted.

Such a series of steps is repeated to finish spraying a predetermined amount of the coating liquid, and finish the coating process when a desired coating layer is formed on the tablet. During the coating process, it is possible to appropriately observe the processing status from the monitoring window 14. When the coating process is completed, the chamber door 11 is opened. Then, the multifunction unit 32 is moved out of the drum 1 and a product discharge cylinder (not shown) is incorporated in the drum 1. Thereafter, the chamber door 11 is closed again, and the product discharge port 17 is opened while the drum 1 is rotated to discharge the coated product.

It goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.
For example, the various numerical values described above are merely examples, and it goes without saying that the values can be changed as appropriate. In addition, the object to be treated in the present invention is not limited to tablets such as the above-mentioned lactose tablets, and foods such as confectionery and gum, other pharmaceuticals, and the like are also applicable. As the sugar coating liquid, sugar coating liquids of various specifications such as those obtained by adding various medicinal ingredients, flavors, pigments and the like to syrup obtained by dissolving sugar in water can be applied.

In the above-described coating apparatus 10, the chamber door 11 is opened to the right because of the control panel 82 disposed on the left side of the front surface of the apparatus. It is also possible to arrange the multifunction unit 32 on the front right side. Furthermore, although the front surface of the housing 2 is divided into three parts and the central part is the chamber door 11, the left and right unit covers 36 and the front cover 25 are communicated with the chamber door 11, and the chamber door 11 is connected. When the is closed, the entire front surface of the housing may be the air supply chamber 13. As a result, the projected area and the internal volume of the air supply chamber 13 can be further increased.

In addition, a cleaning nozzle may be further incorporated in the multifunction unit 32 of the coating apparatus 10. Thereby, it becomes possible to perform the process from coating to washing | cleaning continuously. As shown in FIGS. 5 and 6, in the coating apparatus 10, the spray gun 31 is arranged on one side of the support holder 33 (in the upper left direction in FIG. 6), but the spray gun 31 is on the other side. It can also be disposed (in the diagonally downward right direction in FIG. 6 symmetrically with the spray gun 31). At that time, the installation direction of the spray gun 31 may be changed according to the application, such as sugar coating for one side and film coating for the other side.

It is also possible to adopt a reduction system in which vibration means is incorporated in the multifunction unit 32 and the tablets placed on the support holder 33 are shaken off during processing. Further, a scattering preventing member such as a net may be attached to the front opening 7 so that the tablet being processed does not jump out from the front opening 7 of the drum 1 into the chamber door 11. At this time, a current plate may be used as the scattering prevention member to further stabilize the supply air.

Claims

A pan coating apparatus provided with a rotary drum that is provided to be rotatable about a substantially horizontal rotation axis and has a vent hole in at least a part of an outer peripheral portion thereof, and a housing that houses the rotary drum,
A pan coating apparatus having a drum cooling means installed in the housing and spraying a cooling medium containing fine cooling mist on the outside of the rotating drum.
2. The pan coating apparatus according to claim 1, wherein the cooling mist is fine water droplets having an average particle diameter of 5 μm to 100 μm.
2. The pan coating apparatus according to claim 1, wherein the cooling medium is sprayed by a spray nozzle installed outside the rotating drum, and a spray area of the cooling medium in an outer peripheral portion of the rotating drum has a diameter of 50 mm per spray nozzle. 3. A pan coating apparatus characterized by being -400 mm.
A rotating drum that is provided to be rotatable about a substantially horizontal rotation axis and has a vent hole in at least a part of the outer periphery thereof, a housing that houses the rotating drum, a housing that is installed in the housing, In a pan coating apparatus comprising a drum cooling means for spraying a cooling medium containing a fine cooling mist on the outside, a coating liquid is supplied into the rotating drum to coat the object to be processed in the rotating drum A pan coating method for performing
A pre-cooling step of spraying the cooling medium on the outside of the rotating drum without supplying and exhausting the rotating drum;
A spraying step of spraying the coating liquid onto the object to be processed while rotating the rotating drum without supplying and exhausting the rotating drum;
A pause step of rotating the rotating drum without supplying and exhausting the rotating drum;
And a drying step of rotating the rotary drum while supplying and exhausting the rotary drum.
5. The pan coating method according to claim 4, wherein the cooling medium is sprayed outside the rotating drum not only in the pre-cooling step but also in the spraying step.
5. The pan coating method according to claim 4, wherein the cooling medium is sprayed outside the rotating drum not only in the precooling step but also in the spraying step and the pause step.
5. The pan coating method according to claim 4, wherein the cooling mist is fine water droplets having an average particle diameter of 5 μm or more and 100 μm or less.
5. The pan coating method according to claim 4, wherein a spray area of the cooling medium on an outer peripheral portion of the rotating drum has a diameter of 50 mm to 400 mm per drum cooling means.