Powder mixing device

Abstract

To provide a powder mixing device capable of uniformly mixing powders even when mixing powders of low fluidity or mixing powders in a small-volume mixing chamber.SOLUTION: A powder mixing unit 3 as a powder mixing device mainly comprises a molding die 2 having a molding hole 2a that serves as a mixing chamber for a powder material P and an airflow supply mechanism 10 configured to supply an airflow into the molding hole from below. An airflow A1 is supplied from an air inlet 11a, and an airflow A2 is supplied from an air inlet 11c. The airflow entering an air supply chamber 11b is ejected from an ejection port 12d of a disk section 12b of a rotating member 12. The airflow entering an air supply chamber 11d acts on rotating blades 12c to rotate the rotating member, and is then ejected from an exhaust port 11e. As the rotating member rotates, the ejection port which moves around a vertical central axis O sequentially communicates with each of a plurality of communication ports 13b of a top section 13a arranged along its movement locus. Accordingly, the airflow ejected from the ejection port is supplied into the molding hole via the communication ports at positions where the ejection port communicates with each communication port successively.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a powder mixer that fluidizes and mixes powder with an air current. [Background technology]

[0002] 2. Description of the Related Art There is known an airflow type powder mixer that fluidizes and mixes two or more types of powders contained in a mixing chamber using an airflow (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-57443 [Patent Document 2] Japanese Patent Publication No. 63-283728 Summary of the Invention [Problem to be solved by the invention]

[0004] In an air flow type powder mixer, when mixing powders with low fluidity or when mixing powders in a small volume mixing chamber, the powder in the mixing chamber may not be sufficiently fluidized, making it impossible to mix the powder uniformly.

[0005] The technical objective of the present invention is to provide a powder mixer that can mix powders uniformly even when mixing powders with low fluidity or when mixing powders in a small-volume mixing chamber. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides a powder mixing device comprising a mixing chamber in which two or more types of powder are accommodated, and an air flow supply mechanism which supplies an air flow from below into the mixing chamber, and which fluidizes and mixes the powder accommodated in the mixing chamber by the air flow supplied from the air flow supply mechanism, wherein the air flow supply mechanism comprises an outlet which sprays the air flow toward the mixing chamber at a position radially spaced from the vertical center line of the mixing chamber, and a moving mechanism which moves the outlet around the vertical center line. Effect of the Invention

[0007] The powder mixer of the present invention supplies airflow to the mixing chamber while moving the airflow outlet around the vertical center line by the moving mechanism at a position radially separated from the vertical center line of the mixing chamber, so that the powder in the mixing chamber has a high function of fluidizing the powder. Therefore, even when mixing powder with low fluidity or powder in a small volume mixing chamber, the powder can be mixed uniformly. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a front view showing the overall configuration of a tablet manufacturing apparatus including a powder mixer (powder mixer) according to an embodiment. [Diagram 2] FIG. [Figure 3A] FIG. [Figure 3B] FIG. 4 is a cross-sectional view of the airflow supply mechanism. [Figure 3C] FIG. [Figure 4A] 11 is a perspective view showing the airflow supply mechanism with an upper member of the housing removed; FIG. [Figure 4B] 13 is a plan view showing the airflow supply mechanism with an upper member of the housing removed. FIG. [Diagram 5] 13 is a top view of the top portion of the upper member of the housing in the airflow supply mechanism. FIG. [Figure 6]1 is a cross-sectional view showing a state in which air flows (A1, A2) are supplied to the air flow supply mechanism. FIG. [Figure 7A] FIG. 13 is a perspective view of an airflow supply mechanism according to another embodiment. [Figure 7B] FIG. 11 is a cross-sectional view of an airflow supply mechanism according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] FIG. 1 shows the overall configuration of a manufacturing apparatus for powder compression molded products equipped with a powder mixer (powder mixer 3) according to an embodiment. This manufacturing apparatus is an apparatus for manufacturing, for example, pharmaceutical tablets (hereinafter referred to as "tablets") as powder compression molded products, and has a function of manufacturing the required tablets in a timely manner according to the condition of a patient. In addition, this manufacturing apparatus (hereinafter referred to as "tablet manufacturing apparatus") can be used in a relatively small space such as a drug room in a hospital, clinic, pharmacy, etc., or a laboratory in a university, research institute, or company, and is configured in a small tabletop form so that it can be moved to a desired location.

[0011] The tablet manufacturing apparatus is composed of the following main elements: a weighing section 1 for weighing the powder raw material; a cylindrical mold 2 (see FIG. 2) having a molding hole 2a to which two or more kinds of powder raw material P (main drug, excipient, lubricant, etc.) weighed in the weighing section 1 are supplied; a powder mixing section 3 for fluidizing and mixing the powder raw material P contained in the molding hole 2a of the mold 2 by air flow; a compression molding section 4 for compressing and molding the powder raw material P in the molding hole 2a mixed in the powder mixing section 3 to form a tablet; an inspection section 5 for inspecting the quality of the tablet compressed in the compression molding section 4 in the molding hole 2a; a discharge section 6 for discharging the tablet; and a transport mechanism 7 for transporting the mold 2 to each section. The powder mixing section 3, the compression molding section 4, the inspection section 5, and the discharge section 6 are each disposed above the table surface 8a of the stand table 8, and the mold 2 is transported to each section along the table surface 8a of the stand table 8 by the transport mechanism 7. A control unit 9 having control functions for controlling each unit (powder mixing unit 3, compression molding unit 4, inspection unit 5, and discharge unit 6) and the transfer mechanism 7 and other functions (start / stop button, etc.) is attached to the side of the stand table 8. In the following description, on the paper surface of Fig. 1, the direction along the table surface 8a (the movement direction of the transfer mechanism 7) is defined as the left-right direction, and the direction perpendicular to the table surface 8a and the vertical direction is defined as the up-down direction.

[0012] In this embodiment, the transfer mechanism 7 is mainly composed of a holding unit 7a that holds the mold 2 and a driving unit 7b that moves the holding unit 7a in the left-right direction along the table surface 8a. The driving unit 7b is, for example, a linear guide driven by a servo motor 7b3, and includes a rail 7b1 that extends in the left-right direction along the edge of the table surface 8a, and a carriage (block) 7b2 that moves linearly in the left-right direction on the rail 7b1. The holding unit 7a is connected to the carriage 7b2 and includes a through-hole-shaped holding hole that houses and holds the mold 2. When the servo motor 7b3 is operated and the carriage 7b2 moves in the left-right direction along the rail 7b1, the mold 2 held in the holding hole of the holding unit 7a moves in the left-right direction on the table surface 8a with its lower end surface contacting the table surface 8a and the center line of the molding hole 2a facing up-down (vertical) direction.

[0013] After a specified amount of two or more types of powder raw materials P weighed in the weighing section 1 is supplied to the molding hole 2a of the mold 2 located in the initial position, the start switch of the control section 9 is pressed to operate the device, and the transfer mechanism 7 is activated to transfer the mold 2 held in the holding section 7a to the powder mixing section 3.

[0014] 2 shows the powder mixing section 3. In this embodiment, the powder mixing section 3 is mainly composed of a molding die 2 having a molding hole 2a which serves as a mixing chamber for the powder raw material P, and an airflow supply mechanism 10 which supplies an airflow to the molding hole 2a from below.

[0015] The mold 2 transferred to the powder mixing section 3 is placed on a ventilation plate 3a that is provided so as to be flush with the table surface 8a, and a filter plate 3b is applied from above. The ventilation plate 3a has a ventilation section 3a1 at a position opposite the molding hole 2a, and the ventilation section 3a1 is composed of a porous member having an opening that does not allow the powder raw material P in the molding hole 2a to pass through. The filter plate 3b has a solid-gas separation filter 3b1 at a position opposite the molding hole 2a, and is driven to move up and down by a lifting drive section 3c composed of a linear actuator such as an air cylinder. The space between the mold 2 and the filter plate 3b, and the space between the air flow supply mechanism 10 and the ventilation plate 3a are each sealed with an appropriate sealing means such as an O-ring.

[0016] 3A to 3C show the airflow supply mechanism 10. The airflow supply mechanism 10 includes a housing 11 and a rotating member 12 that is disposed inside the housing 11 and is rotatable around the center line (vertical center line O) of the molding hole 2a that faces in the vertical direction.

[0017] The housing 11 has an air intake port 11a for supplying air flow A1, an air intake chamber 11b into which the air flow A1 supplied from the air intake port 11a flows, an air intake port 11c for supplying air flow A2, an air intake chamber 11d into which the air flow A2 supplied from the air intake port 11c flows, and an exhaust port 11e for exhausting the air flow A2 that has flowed into the air intake chamber 11d.

[0018] In this embodiment, the housing 11 is configured by stacking components, namely, an upper member 13, a first intermediate member 14, a second intermediate member 15, and a lower member 16, in the vertical direction and connecting them to each other. The upper member 13 is formed in a cap shape having a top part 13a, and includes the above-mentioned air supply port 11a and an air supply chamber 11b communicating with the air supply port 11a. The top part 13a of the upper member 13 is provided with a plurality of communication ports 13b, for example, five communication ports 13b. The communication ports 13b are arranged at predetermined intervals around a vertical center line O. Each communication port 13b has the form of a circular hole that penetrates the top part 13a in the vertical direction, and is located at a position radially spaced a predetermined distance from the vertical center line O. The first intermediate member 14 is connected to the lower part of the upper member 13 and includes a bearing part 14a that rotatably supports the rotating member 12. The second intermediate member 15 is connected to the lower part of the first intermediate member 14, and includes the above-mentioned air supply port 11c, an air supply chamber 11d communicating with the air supply port 11c, an exhaust port 11e communicating with the air supply chamber 11d, and a bearing portion 15a that rotatably supports the rotating member 12. The lower member 16 is connected to the lower part of the second intermediate member 15, and houses the lower end of the rotating member 12. The air supply port 11a is disposed so that its horizontal center line passes through the vertical center line O, and the air supply port 11c and the exhaust port 11e5 are disposed so that their horizontal center lines are radially spaced apart from the vertical center line O (see FIG. 3C).

[0019] The rotating member 12 includes a shaft portion 12a, a disk portion 12b fixed to the upper end of the shaft portion 12a, and a rotor 12c provided in the middle portion of the shaft portion 12a. The shaft portion 12a is supported by a bearing portion 14a of the first intermediate member 14 and a bearing portion 15a of the second intermediate member 15 so as to be rotatable about a vertical center line O. The disk portion 12b is located in the air supply chamber 11b, and its upper surface is covered by a top portion 13a of the upper member 13. There is a small gap between the top surface of the disk portion 12b and the lower surface of the top portion 13a, which is small enough not to interfere with the rotation of the disk portion 12b. The rotor 12c is disposed in the air supply chamber 11d.

[0020] 4A and 4B show the state with the upper member 13 removed. One or more, for example one, outlet 12d is provided on the disk portion 12b. The outlet 12d is disposed at a position spaced a predetermined distance radially from the vertical centerline O. The outlet 12d has the form of a circular hole that penetrates the disk portion 12b in the vertical direction and has the same diameter as the communication port 13b of the top portion 13a. The rotating member 12 (shaft portion 12a, disk portion 12b, rotor 12) is driven to rotate in the direction of the arrow shown in the figure by airflow A2 flowing from the air intake port 11c into the air supply chamber 11d.

[0021] 5 is a view of the top part 13a of the housing 11 (upper member 13) seen from above. When the rotating member 12 rotates around the vertical center line O in the housing 11 (rotating in the direction of the arrow shown in the figure), the nozzle 12d of the disk part 12b moves around the vertical center line O with the rotation of the rotating member 12. The movement trajectory T of the center of this nozzle 12d describes a circle centered on the vertical center line O. The multiple communication ports 13b of the top part 13a are arranged at predetermined intervals (equally spaced) along the movement trajectory T so that their centers are located on the movement trajectory T of the nozzle 12d. As the rotating member 12 rotates, the nozzle 12d moving around the vertical center line O sequentially communicates with each of the multiple communication ports 13b arranged along the movement trajectory T.

[0022] When the molding die 2 is transferred to the powder mixing section 3 and placed on the ventilation plate 3a in the manner shown in Fig. 2, an airflow A1 (compressed air) is supplied from the air supply port 11a, and an airflow A2 (compressed air) is supplied from the air supply port 11c, as shown in Fig. 6. The airflows A1 and A2 may be supplied from a common airflow supply source, or may be supplied from separate airflow supply sources.

[0023] Airflow A1 that flows into air supply chamber 11b from air supply port 11a is ejected from outlet 12d of disk portion 12b. On the other hand, airflow A2 that flows into air supply chamber 11d from air supply port 11c acts on rotor 12c, rotates rotating member 12, and is then exhausted from exhaust port 11e.

[0024] As the rotating member 12 rotates, the nozzle 12d moves around the vertical center line O and sequentially communicates with each of the multiple communication ports 13b of the top portion 13a arranged along its movement trajectory T (see FIG. 5). Accordingly, the airflow A1 ejected from the nozzle 12d is supplied to the molding hole 2a through the communication port 13 at a position where the nozzle 12d sequentially communicates with each communication port 13b in the rotation direction of the rotating member 12 (the movement direction of the nozzle 12d). Therefore, the airflow A1 ejected from the nozzle 12d is ejected intermittently in the form of a pulse wave (pulsating wave) from each of the multiple communication ports 13b and is supplied to the molding hole 2a. In this way, by moving the air flow A1 outlet 12d at a position radially spaced from the vertical center line O of the molding hole 2a, which serves as the mixing chamber, around the vertical center line O while intermittently supplying the air flow A1 to the molding hole 2a in the form of a pulse wave (pulsating wave), the powder raw material P can be effectively fluidized and uniformly mixed even within the small-volume molding hole 2a.

[0025] When the mixing of the powder raw material P in the powder mixing section 3 is completed, the mold 2 held in the holding section 7a is transferred to the compression molding section 4 by the transfer mechanism 7. In the compression molding section 4, a punch is inserted into the forming hole 2a of the mold 2 to compress and mold the powder raw material P in the forming hole 2a into a tablet form. Then, when the compression molding in the compression molding section 4 is completed, the mold 2 held in the holding section 7a is transferred to the inspection section 5 by the transfer mechanism 7. In the inspection section 5, an optical sensor such as a near-infrared spectroscopic sensor (NIR sensor) is used to determine the quality of the tablet compressed in the forming hole 2a (tablet ingredient content, active ingredient content, thickness, hardness, moisture content, dissolution, presence or absence of impurities, etc.) and inspect whether the quality of the tablet in the forming hole 2a meets the required quality level. This inspection result is output to the control section 9 as a signal of "conformity" or "non-conformity". When the signal received from the inspection unit 5b is "non-conformity", the control unit 9 notifies the operator of the "non-conformity" inspection result by appropriate means (such as an alarm sound or display).

[0026] After the above inspection process, the molding die 2 held in the holding part 7a is transferred to the discharge part 6 by the transfer mechanism 7. Then, in the discharge part 6, the tablets in the molding holes 2a are pushed out by an ejection pin or the like and collected in a collection part such as a collection container. In this way, when the discharge of the tablets in the discharge part 6 is completed, the holding part 7a is returned to its initial position by the transfer mechanism 7.

[0027] If the operator has not been notified of the "non-compliant" inspection result regarding the tablet quality by the control unit 9, the operator collects the tablets collected in the collection unit and provides them for the patient to take. On the other hand, if the operator has been notified of the "non-compliant" inspection result regarding the tablet quality by the control unit 9, the operator discards the tablets collected in the collection unit.

[0028] The above tablet manufacturing process is repeated until the required number of tablets is obtained.

[0029] In the tablet manufacturing apparatus equipped with the powder mixing section 3 of this embodiment, two or more weighed powder raw materials P are supplied to the forming hole 2a of the mold 2, and each process of tablet manufacturing (mixing of raw material powders, compression molding and quality inspection, tablet quality inspection) is all performed within the forming hole 2a of the mold 2, so that the variation in component content is small, tablets of the target quality can be manufactured, and material loss during the manufacturing process can be minimized. In addition, the powder mixing section 3 intermittently supplies the airflow A1 to the forming hole 2a in the form of a pulse wave (pulsating wave) while moving the outlet 12d of the airflow A1 around the vertical center line O of the forming hole 2a, which serves as the mixing chamber, at a position radially separated from the vertical center line O of the forming hole 2a, so that the function of fluidizing the powder raw material P is high, and the powder raw material P can be effectively fluidized and uniformly mixed even in the small-volume forming hole 2a.

[0030] 7A and 7B show another embodiment of the airflow supply mechanism 10 constituting the powder mixer 3 described above. The airflow supply mechanism 10 of this embodiment is substantially different from the airflow supply mechanism 10 of the above-mentioned embodiment in that the exhaust port (11e) of the housing 11 (second intermediate member 15) is eliminated, and a communication portion 14b is provided to communicate the air supply chamber 11b and the air supply chamber 11d. The airflow A2 flowing into the air supply chamber 11d from the air supply port 11c acts on the rotor 12c to rotate the rotary member 12, and then flows into the air supply chamber 11b through the communication portion 14b. The airflow A2 flowing into the air supply chamber 11b merges with the airflow A1 flowing into the air supply chamber 11b from the air supply port 11a, is ejected from the ejection port 12d, and is supplied to the molding hole 2a through the communication port 13b. Compared to the airflow supply mechanism 10 of the above-mentioned embodiment, the airflow A2 that rotates the rotating member 12 is not exhausted but is supplied to the molding hole 2a together with the airflow A1, thereby reducing energy consumption. Since other matters are similar to those explained for the airflow supply mechanism 10 of the above-mentioned embodiment, the same reference numerals are used to denote substantially the same members and parts, and duplicate explanations will be omitted.

[0031] In the above embodiment, the air outlets 12d of the rotating member 12 (disk portion 12b) of the airflow supply mechanism 10 may be provided in a plurality of locations around the vertical center line O (along the movement path T).

[0032] In the above embodiment, the airflow A1 (or the airflow A1+A2) ejected from the ejection port 12d of the rotating member 12 (disk portion 12b) of the airflow supply mechanism 10 may be supplied to the molding hole 2a in the form of a continuous flow, not in the form of a pulse wave (pulsating wave). For example, a single through hole is provided in the top portion 13a of the housing 11 of the airflow supply mechanism 10 so as to encompass the formation portion of the above-mentioned multiple communication ports 13b, and the airflow A1 (or the airflow A1+A2) ejected from the ejection port 12d is supplied to the molding hole 2a through the single through hole. In this configuration, if the airflow A1 to be supplied to the air intake port 11a is made into a pulse wave (pulsating wave), the pulse wave (pulsating wave) airflow A1 can be supplied to the molding hole 2a.

[0033] In addition, the airflow supply mechanism can be configured with the following main elements: one or more airflow ejection nozzles each having an airflow outlet and arranged at a position radially spaced apart from the vertical center line of the mixing chamber; an air supply section which supplies an airflow to the airflow ejection nozzle; and a rotation mechanism which rotates the airflow ejection nozzle around the vertical center line of the mixing chamber.

[0034] The present invention can be applied not only to the powder mixing section of the above-mentioned tablet manufacturing apparatus, but also to the powder mixing section of other manufacturing apparatuses for powder compression molded products, and further can be widely applied to general air flow type powder mixing devices in which two or more types of powder contained in a mixing chamber are fluidized by an air flow and mixed. [Explanation of symbols]

[0035] 2 Molding mold 2a Molding hole 3 Powder mixing section 10 Airflow supply mechanism 11. Housing 11a Air intake (first air intake) 11b Air supply chamber (first air supply chamber) 11c Air intake (second air intake) 11d Air supply room (second air supply room) 11e Exhaust port 12 Rotating members 12c Rotor 12d spout 13a Heaven 13b Communication port A1 Airflow (First Airflow) A2 airflow (second airflow) T Orifice movement trajectory

Claims

1. A powder mixer comprising a mixing chamber in which two or more types of powder are accommodated, and an air flow supply mechanism that supplies an air flow from below to the mixing chamber, the powders accommodated in the mixing chamber being fluidized and mixed by the air flow supplied from the air flow supply mechanism, The powder mixing device characterized in that the air flow supply mechanism includes an outlet that ejects the air flow toward the mixing chamber at a position radially spaced from the vertical center line of the mixing chamber, and a moving mechanism that moves the outlet around the vertical center line.

2. 2. The powder mixer according to claim 1, wherein the nozzle is provided on a rotating member that is rotatable about a center line in the vertical direction, and the moving mechanism rotates the rotating member by an airflow.

3. 2. The powder mixer according to claim 1, wherein the airflow supply mechanism includes an airflow control unit that controls a flow of the airflow so that the airflow ejected from the ejection port is intermittently supplied to the mixing chamber.

4. The powder mixing device of claim 3, wherein the airflow control section is composed of a member having a plurality of communication ports arranged at predetermined intervals along a movement trajectory of the nozzle which moves around the vertical center line, and the airflow ejected from the nozzle is supplied to the mixing chamber through the communication ports at a position where the nozzle sequentially communicates with each of the plurality of communication ports as the nozzle moves.

5. 2. The powder mixer according to claim 1, the airflow supply mechanism includes a housing and a rotating member that is disposed inside the housing and is rotatable about a center line in the up-down direction; the housing has a first air supply port for supplying a first air flow, a first air supply chamber into which the first air flow supplied from the first air supply port flows, a second air supply port for supplying a second air flow, a second air supply chamber into which the second air flow supplied from the second air supply port flows, and an exhaust port for exhausting the second air flow that has flowed into the second air supply chamber, the rotating member is provided with the outlet and a rotor, the outlet communicates with the first air supply chamber, and the rotor is located within the second air supply chamber; the moving mechanism rotates the rotating member via the rotating blades by the second air flow flowing into the second air supply chamber from the second air supply port, the first airflow is ejected from the ejection port of the rotating member, and the second airflow is exhausted from the exhaust port.

6. 6. The powder mixing device of claim 5, wherein the housing has a top portion on which a plurality of communication ports are arranged at predetermined intervals along a movement trajectory of the nozzle which moves around the vertical center line, and the airflow ejected from the nozzle is supplied to the mixing chamber through the communication ports at a position where the nozzle sequentially communicates with each of the plurality of communication ports as the nozzle moves due to the rotation of the rotating member.

7. 2. The powder mixer according to claim 1, the airflow supply mechanism includes a housing and a rotating member that is disposed inside the housing and is rotatable about a center line in the up-down direction; the housing has a first air supply port for supplying a first air flow, a first air supply chamber into which the first air flow supplied from the first air supply port flows, a second air supply port for supplying a second air flow, a second air supply chamber into which the second air flow supplied from the second air supply port flows, and a communication portion that communicates the second air supply chamber with the first air supply chamber, the rotating member is provided with the outlet and a rotor, the outlet communicates with the first air supply chamber, and the rotor is located within the second air supply chamber; the moving mechanism rotates the rotating member via the rotating blades by the second air flow flowing into the second air supply chamber from the second air supply port, the first air flow, and the second air flow that flows from the second air supply chamber into the first air supply chamber via the communicating portion, are ejected from the outlet of the rotating member.

8. 8. The powder mixing device of claim 7, wherein the housing has a top portion on which a plurality of communication ports are arranged at predetermined intervals along a movement trajectory of the nozzle which moves around the vertical center line, and the first and second air flows ejected from the nozzle are supplied to the mixing chamber through the communication ports at a position where the nozzle sequentially communicates with each of the plurality of communication ports as the nozzle moves due to the rotation of the rotating member.

9. 9. The powder mixer according to claim 1, wherein the mixing chamber is a molding hole of a mold for compression molding a powder raw material, and the powder is mixed in the molding hole.

10. A manufacturing apparatus for a powder compression molded product, comprising the powder mixer according to claim 9.

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