JP5197932B2 - Powder microfeeder - Google Patents

Description

  The present invention relates to a fine powder supply apparatus that supplies a small amount of powder of, for example, several μm to a supply target.

In the field of coating by spraying powder dyes and pigments, and the field of compounding and blending powder chemicals and precious metals, supply devices that supply powder in a fixed amount are used. As this type of device, for example, a device using a screw feeder or a table feeder (Patent Document 1 or the like), an apparatus for discharging a powder by vibrating a container that stores the powder (Patent Document 2 or the like), or the like is known. It is.
JP 2004-151118 A JP 2005-289632 A

  Various apparatuses for supplying powder as described above are known, but it is difficult to supply a small amount of any of them. For example, in the case of a supply device using a screw feeder, a device that supplies 50 to 100 g per hour is still commercially available, but there is no device that can supply powder in a trace amount of several g / h or less. Absent.

  In addition to the above, an apparatus for supplying powder by pneumatic conveyance is also known, but in order to convey a small amount of powder, an extremely fine powder feed pipe is required, and the powder is fed inside the pipe. Clogging is likely to occur. In addition, if the flow rate of compressed air is too small to supply a minute amount, the powder tends to stay in the powder feed pipe due to insufficient powder conveying force, and if the flow rate of compressed air is increased, a small amount of supply will not occur. It becomes difficult.

  An object of the present invention is to provide a fine powder supply device capable of supplying a small amount of powder using air conveyance.

The fine powder supply device of the present invention has a storage container for storing powder, one end disposed above the upper surface of the powder in the storage container, and the other end disposed outside the storage container. A powder feed pipe, a first compressed air supply means for supplying compressed air from below into the storage container, and a second compressed air supply means for supplying compressed air in the middle of the powder feed pipe. with which the storage container is sealed with the powder except the powder feeding tube, the first compressed air supply means may be suspended powder in the space portion of the storage container , was suspended powder has flowed into the powder feed pipe, the second compressed air supply means may be dilute the powder that has flowed into the powder feed pipe, air transport, It is characterized by that.

The fine powder supply device further includes a vibration mechanism for vibrating the storage container ,
The vibration mechanism elastically supports the main body from below, a substrate connected to the storage container, a main body that fixes one end of the substrate, a vibration generating unit that vibrates the substrate, and The vibration generating unit includes an electromagnet and is fixed to the main body, and intermittently adsorbs the substrate by passing a current through the electromagnet .

  It is preferable that the first compressed air supply means is configured to continuously supply compressed air at a constant flow rate into the storage container.

  The second compressed air supply means is preferably configured to continuously supply compressed air at a constant flow rate to the powder feed pipe.

  The storage container includes a ventilation member that allows passage of air and prevents passage of powder therein, and the ventilation member receives the powder in the storage container from below, and the first compression It is preferable that the air supply means is configured to supply compressed air from below the ventilation member.

  According to the first aspect of the present invention, the compressed air is supplied into the storage container from below by the first compressed air supply means, thereby fluidizing the powder in the storage container and floating in the space portion in the storage container. Powder is introduced from one end of the powder feed tube. Therefore, it is possible to flow a small amount of powder into the powder feed pipe. Further, the second compressed air supply means can create an air flow in the powder conveying direction in the powder feeding pipe, and the powder flowing into the powder feeding pipe can be conveyed by air.

  According to the invention of claim 2, in order to allow a small amount of powder to flow into the powder feed pipe, the amount of compressed air supplied by the first compressed air supply means is reduced, whereby the powder in the powder container is reduced. Even if the fluidization of the liquid becomes insufficient, it is less likely that the powder is biased and reduced in the storage container by vibrating the storage container by the vibration mechanism.

  According to the invention of claim 3, since the compressed air is continuously supplied into the storage container, the powder can be suspended substantially uniformly in the space in the storage container, and the powder is supplied in a substantially constant amount. It can flow into the feed pipe.

  According to the invention of claim 4, since compressed air is continuously supplied to the powder feed pipe, the powder flowing into the powder feed pipe can be uniformly conveyed by air and discharged.

  According to the invention of claim 5, the compressed air can be supplied to the powder on the ventilation member substantially uniformly by the first compressed air supply means, and the powder aggregates or closes in the storage container. Can be prevented.

  FIG. 1 is a schematic overall configuration diagram of a powder microfeeder according to an embodiment of the present invention. The supply device 11 includes a storage container 12 that can store powder, a vibration mechanism 13 that vibrates the storage container 12, and a transport mechanism 14 that transports the powder in the storage container 12 by air.

  FIG. 2 is a longitudinal sectional view of the storage container 12. The storage container 12 has a cylindrical container body 17 with flanges 15 and 16 projecting from upper and lower ends, and a lid for closing the upper opening of the container body 17. A body 18, a cover plate 19 that closes the lower opening of the container body 17, and a ventilation member 20 disposed slightly above the cover plate 19 in the container body 17 are provided.

  The container body 17 is made of a metal such as stainless steel and has an overall height of about 80 mm and an outer diameter of the body portion of about 60 mm. Moreover, the container main body 17 is comprised by joining the cylinder part 21 and the funnel part 23 to an up-down direction. The cylindrical portion 21 is formed in a cylindrical shape, and includes a flange portion 15 that protrudes radially outward at the upper end outer peripheral portion.

  The funnel portion 23 has a conical shape in which the upper inner surface 23a is inclined so that the inner diameter decreases downward, and the lower inner surface 23b is formed in a cylindrical shape having a diameter larger than the minimum inner diameter of the upper inner surface. A step portion 23c is formed between 23a and the lower inner surface 23b. The inclination angle of the upper inner surface 23a is about 45 °. A flange portion 16 that protrudes outward in the radial direction is formed on the outer periphery of the lower end of the funnel portion 23. The flange portion 16 is bolted to the substrate 27 while being mounted on the substrate 27 of the vibration mechanism 13.

  The cover plate 19 is a plate material having a circular shape in plan view, and an outer peripheral portion thereof is fixed to the lower surface of the funnel portion 23 via bolts 28. An opening 27 a is formed in the substrate 27 at a portion where the cover plate 19 is attached. A first air flow pipe 31 to be described later is connected to the cover plate 19 on the center line of the container body 17.

  The ventilation member 20 is provided inside the ring-shaped support frame 33 and allows passage of air, but prevents passage of the powder P in the container body 17. The ventilation member 20 receives the powder P in the container body 17 from below. The support frame 33 is sandwiched between the cover plate 19 and the step portion 23 c via an O-ring 34. As this ventilation member 20, what laminated | stacked and couple | bonded the some sintered metal mesh can be used, for example.

  The lid 18 is formed in a disc shape in plan view having an outer diameter substantially the same as the flange portion 15 at the upper end of the container body 17. The lid 18 is fixed to the container main body 17 by the clamp tool 36 with the seal member 35 interposed between the lid 18 and the upper surface of the container main body 17 so as to seal the container main body 17.

  A powder feeding tube 40 is integrally fixed to the lid 18. The powder feed pipe 40 is formed of a straight pipe material such as stainless steel, and is arranged in the vertical direction, and penetrates the center of the lid 18 in the vertical direction. The lower end portion of the powder feed pipe 40 is arranged at the upper part in the container body 17, specifically, slightly below the lid body 18, and more than the upper surface of the powder P stored in the container body 17. It is arranged above. Further, the lower end portion of the powder feeding pipe 40 faces the first air flow pipe 31.

  The upper side of the powder feed tube 40 protrudes upward from the lid 18. The powder feed tube 40 has an inner diameter of about 2 mm, for example. A second air flow pipe 42 is connected to the powder feed pipe 40 via a T-shaped joint pipe 41.

  As shown in FIG. 1, the transport mechanism 14 includes a compressed air supply source 44 such as a blower or a compressor that generates compressed air. A main air flow pipe 45 is connected to the compressed air supply source 44, and the first and second air flow pipes 31 and 42 and a pressure gauge 47 are connected to the main air flow pipe 45 through an air chamber 46. ing. The first and second air flow pipes 31 and 42 are respectively provided with flow meters 48 and 48 and flow rate adjusting valves 49 and 49 so that the flow rate of air flowing through the pipes 31 and 42 can be adjusted. The second air flow pipe 42 is provided with a pressure gauge 50, and the lid 18 of the storage container 12 is provided with a pressure gauge 51 that measures the pressure in the storage container 12.

  Here, the compressed air supply source 44, the main air flow pipe 45, the air chamber 46, the first air flow pipe 31 and the like constitute the first compressed air supply means 52, and the compressed air supply source 44, the main air flow pipe 45, A second compressed air supply means 53 is configured by the air chamber 46, the second air flow pipe 42, and the like.

  In the first and second air flow pipes 31 and 42, compressed air having substantially the same flow rate, for example, about 0.3 to 3 L / min flows. The first and second air flow pipes 31 and 42 have substantially the same inner diameter (for example, about 2 mm), and the inner diameter is larger than the inner diameter of the powder feed pipe 40.

  The vibration mechanism 13 includes a main body portion 55, an elastic support portion 56 that elastically supports the main body portion 55 from below, a substrate 27, and a vibration generating portion 57 that vibrates the substrate 27. The elastic support portion 56 is constituted by a plurality of leg portions 58 extending downward from the bottom surface of the main body portion 55, and the leg portions 58 are constituted by compression coil springs. The board | substrate 27 is formed in the substantially square shape by the upper part extended in a horizontal direction, and the lower part which inclines inclining downward from the upper part. The storage container 12 is connected to the upper portion of the substrate 27, and the lower end of the substrate 27 is fixed to one side portion of the main body portion 55 with a bolt or the like.

  The vibration generating unit 57 intermittently attracts the substrate 27 by causing a current to flow intermittently (for example, several to several tens of times per second) through the coil of the electromagnet 59, and vibrates as indicated by an arrow a. . As a result, the storage container 12 attached to the substrate 27 is vibrated together.

<Operational effects of this embodiment>
Next, the effect of the supply apparatus having the above configuration will be described.

  As shown in FIG. 1, the powder P is stored in the storage container 12 in a state of being placed on the ventilation member 20. The lower end portion of the powder feeding tube 40 is disposed above the powder P and opens downward. When the compressed air supply source 44 is operated, the compressed air flows to the first and second air flow pipes 31 and 42 through the air chamber 46, and the flow rate is adjusted by the flow rate adjusting valves 49 and 49.

  The compressed air flowing through the first air flow pipe 31 passes through the ventilation member 20 and continuously flows into the storage container 12 at a constant flow rate to fluidize the powder P on the ventilation member 20 (floating suspension). Let At this time, the powder P ′ floats like smoke in the space S formed on the upper side of the powder P, and the suspended powder P ′ flows into the powder feed pipe 40 from the lower end.

  The compressed air flowing through the second air flow pipe 42 continuously flows into the powder feed pipe 40 at a constant flow rate and generates an upward conveying flow as indicated by an arrow b. The powder P that has flowed into the powder feed pipe 40 rides on the transport flow and flows upward, and the end of the powder feed pipe 40 (if a hose or the like is connected to the powder feed pipe 40, It is discharged as a very thin smoke from the end). Accordingly, it is possible to supply the powder P to the supply location in minute amounts. Although the supply amount of the supply device 11 depends on the type of the powder P, it can be, for example, several μg to several g per hour.

  As described above, compressed air is supplied from the lower side of the storage container 12 through the ventilation member 20 from the first air flow pipe 31 (first compressed air supply means 52), and the powder is supplied to the space S in the storage container 12. By suspending P ′, a very small amount of powder P can be caused to flow into the powder feed tube 40. In addition, by flowing a constant flow of air continuously through the first air flow pipe 31, the powder P ′ can be suspended in the space S with a substantially uniform concentration, whereby the powder feed pipe The powder P can be allowed to flow into the 40 by a certain amount.

  Furthermore, by supplying compressed air from the middle of the powder feed pipe 40 via the second air flow pipe 42 (second compressed air supply means 53), the powder P can be smoothly conveyed, The concentration of the powder P can be further diluted and made uniform. Therefore, the powder P hardly clogs or stays in the powder feed pipe 40.

  Further, by supplying a constant flow rate of compressed air continuously in the middle of the powder feed pipe 40, it is possible to prevent density from being generated in the discharged powder P.

  As the powder P is discharged through the powder feed pipe 40, the powder P in the storage container 12 gradually decreases. At this time, if the powder P in the storage container 12 is not sufficiently fluidized, for example, the flow rate of the compressed air supplied from the first air flow pipe 31 in order to discharge the powder P minutely is changed. When it is made smaller, the powder P may decrease from the central side in the storage container 12, remain in a state of being biased near the inner wall, and may not be completely discharged. Therefore, in the present embodiment, the powder storage container 12 is vibrated by operating the vibration mechanism 13 while the powder is being conveyed, and the powder P in the container 12 is also vibrated, so that the powder P is leveled so as not to be biased so that the powder P in the storage container 12 can be completely discharged.

  In other words, by providing the vibration mechanism 13 as in the present embodiment, the flow rate of the compressed air supplied through the first air flow pipe 31 is reduced, and the floating of the powder P in the space S is further reduced. Even if a smaller amount of the powder P ′ is allowed to flow into the powder feeding pipe 40, the unevenness of the powder P in the storage container 12 can be prevented.

<Other effects>
(1) As shown in FIG. 2, the powder feed tube 40 is integrally fixed to the lid 18, so that the powder feed tube 40 can be simply attached to the container body 17 by attaching the lid 18. The lower end can be arranged at an appropriate height (that is, above the powder P). Further, by removing the lid 18 from the container body 17, the powder feeding tube 40 can be removed from the container body 17 at the same time. Therefore, the replenishment operation of the powder P to the container body 17 can be performed easily and quickly.

  (2) Since the powder feeding pipe 40 protrudes upward from the lid 18 of the storage container 12, the second air flow pipe 42 and other hoses can be easily connected to the powder feeding pipe 40. It can be carried out.

  (3) As shown in FIG. 1, since the compressed air to the 1st, 2nd air flow pipes 31 and 42 is produced | generated by the common compressed air supply source 44, for every air flow pipes 31 and 42, individually Compared with the case where the compressed air supply source 44 is provided, the apparatus can be simplified and the cost can be reduced.

  (4) The supply device 11 does not discharge the powder P downward from the storage container 12, but discharges the powder P upward from the storage container 12 via the powder feed pipe 40. It is possible to prevent the powder P from being clogged in the lower part of the storage container 12 and the bridge from being reduced.

  The present invention is not limited to the above-described embodiment, and the design can be changed as appropriate. For example, the flow rate of air flowing through the air flow pipes 31 and 42, the dimensions of the storage container 12, the powder feed pipe 40, and the air flow pipes 31 and 42 are merely examples, and the present invention is limited. It is not a thing.

  The supply device of the present invention is used for spraying and supplying powder pigments (paints), for example, for painting and creating design images, or for spraying and supplying fine powder additives and catalysts for chemical reaction of chemicals. It can be used to do. Further, as another application, a device for dropping molten metal silicon to produce spherical silicon can be used to blow powdered silicon into the device in order to promote solidification of the spherical silicon.

It is a schematic whole block diagram of the powder trace amount supply apparatus which concerns on embodiment of this invention. It is a longitudinal cross-sectional view of a storage container.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Fine powder supply apparatus 12 Storage container 13 Vibration mechanism 14 Conveyance mechanism 44 Compressed air supply source 52 1st compressed air supply means 53 2nd compressed air supply means

Claims (5)

A storage container for storing powder;
One end is disposed above the upper surface of the powder in the storage container, and the other end side is disposed outside the storage container;
First compressed air supply means for supplying compressed air from below into the storage container;
Second compressed air supply means for supplying compressed air in the middle of the powder feed pipe,
The storage container seals the powder except for the powder feeding pipe,
The first compressed air supply means may be suspended powder in the space portion of the storage container, which was suspended powder to flow into the powder feed tube,
The second compressed air supply means may be dilute the powder that has flowed into the powder feed pipe, air transport, characterized in that, the powder trace supply. A vibration mechanism for vibrating the storage container ,
The vibration mechanism elastically supports the main body from below, a substrate connected to the storage container, a main body that fixes one end of the substrate, a vibration generating unit that vibrates the substrate, and An elastic support part,
The said vibration generation part is equipped with the electromagnet, and is being fixed to the said main-body part, The said board | substrate is adsorb | sucked intermittently by sending an electric current through the said electromagnet, It is characterized by the above-mentioned. Powder trace supply device.   The fine powder supply device according to claim 1, wherein the first compressed air supply means is configured to continuously supply compressed air at a constant flow rate into the storage container.   The fine powder supply apparatus according to claim 1, wherein the second compressed air supply means is configured to continuously supply compressed air at a constant flow rate to the powder feed pipe. The storage container includes a ventilation member that allows passage of air and prevents passage of powder therein, and the ventilation member receives the powder in the storage container from below,
The fine powder supply device according to claim 1, wherein the first compressed air supply means is configured to supply compressed air from below the ventilation member.

Images