JP2003341850A - Powder supplying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To install a screw feeder in a vertical direction, downsize a device, reduce cost and improve performance. <P>SOLUTION: This device includes the screw feeder 10 having a rotation shaft 25 rotated by a predetermined drive source and blades 26 fixed on an outer circumference of the shaft 25 and having spiral blades, discharges powder contained within a container 2 from a discharge port 3 placed on a lower portion of the container 2 by rotation movement of the feeder 10, and supplies it to another mechanism. In this device, the screw feeder 1 is placed in a vertical direction so that powder is conveyed to a guide portion 14 communicated with the port 3 from above to below, and the blade 26 is inclined downward. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for discharging a powder contained in a container to the outside and supplying it to another mechanism, for example, when transferring powder in a silo to a container. And the like, and particularly to those having a screw feeder.

[0002]

2. Description of the Related Art As a powder feeder using a conventional screw feeder, as shown in FIG. 10, powder that has fallen from the bottom of a container such as a silo is laterally transferred by the rotational movement of the screw feeder. There was a format to do. Further, in JP-A-6-340317, in a device for laterally transferring powder by a screw feeder, a screw is used for the purpose of preventing powder particles from adhering to the inner wall of a casing in which the screw feeder is installed. A configuration is disclosed in which the angle formed by the surface of the wing on the transfer direction side and the shaft is less than 90 °.

[0003]

However, in the conventional structure, since the screw feeder is installed in the lateral direction, it is necessary to provide a horizontally long casing outside the container and install the screw feeder inside the casing. there were. This causes problems such as an increase in size of the device and an increase in cost.

Therefore, an object of the present invention is to make it possible to install a screw feeder in a vertical direction in a powder supply device, to downsize the device, reduce cost, and improve performance.

[0005]

In order to solve the above-mentioned problems, a powder supply apparatus according to the present invention has a rotary shaft rotated by a predetermined drive source and a spiral shape fixed to the outer peripheral surface of the rotary shaft. And a screw feeder having a blade having, and the rotational movement of the screw feeder causes the powder contained in the container to be discharged from the discharge port provided at the bottom of the container to another mechanism. The powder feeder for supplying the screw feeder, wherein the screw feeder is arranged in a vertical direction so as to convey the powder downward from above in a guide portion communicating with the discharge port, and the blade is directed downward. It is characterized by being inclined (claim 1).

[0006] According to this, due to the inclination provided on the blade of the screw feeder, the powder on the blade gathers near the wall surface of the guide portion, and resistance is generated between the powder and the wall surface. Since the body slips on the blade, the powder is smoothly transferred downward and discharged from the discharge port. If a blade that does not have the inclination is used, the powder will rotate while remaining on the blade, and will not be transferred downward. As described above, according to the present invention, the screw feeder can be installed in the vertical direction, and it is possible to eliminate members such as a horizontally long duct that are required when the screw feeder is installed in the horizontal direction. Can be downsized, cost can be reduced, performance can be improved, and the like.

Further, in the powder supply apparatus according to the present invention, the guide portion has a substantially conical shape whose diameter gradually decreases as it approaches the discharge port, and the blade is adapted to the conical shape. The spiral diameter becomes smaller as it goes downward, and the pitch between the upper and lower ends of the circumferential end becomes larger as it goes downward (claim 2).

As the guide portion (hopper), a substantially conical shape is often used, but the shape of the screw feeder must match the shape of the guide portion. At this time, simply by gradually reducing the spiral diameter of the blade of the screw feeder in accordance with the conical shape of the guide portion, the space formed between the blades becomes smaller as it goes downward, so that the powder Although problems such as clogging occur, as in this configuration, by increasing the pitch between the top and bottom of the circumferential edge of the blade as it goes downward, the space formed between the blades is uniform over the whole. Therefore, the powder can be discharged smoothly without being clogged.

Further, in the present invention, various shapes other than the above can be applied to the screw feeder, provided that the blade is inclined downward. For example, a double-threaded screw or the like having a plurality of blades can be cited (claim 3).

The inclination provided on the blade is
The angle should be appropriately changed according to the type of powder and the like, but it is particularly preferable that the angle is 45 ° with respect to the rotation axis (claim 4). When powder is dropped on a flat plate little by little, it accumulates in a mountain-like shape, and the angle of inclination of this mountain is called the angle of repose. If the inclination angle provided on the blade is larger than the angle of repose, the powder slides on the blade toward the wall surface of the guide portion. The angle of repose varies depending on the type of powder, but is approximately 45 ° or less. Therefore, by adjusting the inclination provided on the blade to 45 ° or more, most types of powder can be allowed. .

Further, in the present invention, since the screw feeder is installed in the vertical direction, the drive source and the vibrator can be installed on the upper part of the screw feeder easily and while reducing the mounting space. (Claim 5). As a result, it is possible to obtain effects such as downsizing of the device, improvement of powder discharging property, and prevention of adhesion.

Further, a stay for supporting at least one of the screw feeder, the drive source and the vibrator is provided, and at least one of the drive source and the vibrator is passed through a through hole formed inside the stay. It is preferable to provide a cooling means for blowing air toward (Claim 6).

As a result, heat generation of the drive source and the vibrator including the electric motor and the like can be suppressed, so that the maintainability of the performance can be improved.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. The powder supply apparatus 1 according to the first embodiment shown in FIG. 1 has a silo (container).
The powder P housed inside 2 is supplied to another mechanism such as a container, and is provided with a discharge mechanism 5 capable of discharging the powder P inside the silo 2 from the discharge port 3 in an arbitrary amount. Is configured.

As shown in FIGS. 2 and 3, the discharging mechanism 5 includes a screw feeder 10, an electric device housing portion 11,
The discharge opening / closing means 12 is provided. As shown in FIGS. 2 to 4, the screw feeder 10 includes a rod-shaped rotating shaft 25 made of stainless steel, and a spiral blade 26 made of stainless steel and fixed to an outer peripheral surface of the rotating shaft 25. A hopper (guide portion) 14 connected and fixed to an opening 13 formed at the bottom of the silo 2.
Placed inside. The opening at the lower end of the hopper 14 serves as the discharge port 3.

As shown in FIG. 3, the electric device housing 11 includes an electric motor 15, a vibrator 16, a spring 19, etc., a cone shell 18, a fixing member 20, and a sealing rubber 21.
It is housed in a casing composed of the above, and is supported by an upper stay 24 fixed to the opening 13 of the silo 2 via a fixing member 20. The rotating shaft 2
5, the upper end of the electric motor 15 is connected to the electric motor 15 through a predetermined transmission mechanism, and the lower end of the rotary shaft 25 is rotatable to a rod-shaped lower stay 23 provided at the lower end of the hopper 14. By being supported by the rotary shaft 25 (screw feeder 10), the rotary shaft 25 (screw feeder 10) can be arbitrarily rotated by the output of the electric motor 15 controlled by a predetermined control unit. In addition, the upper stay 24 has a side 2 located at the uppermost part of the blade 26.
It is provided close to 6a. As a result, the powder P on the blade 26 is transferred to the intake port 27 of the blade 26 (see FIG.
(See (b)). When the remaining amount of the powder P becomes small, the pressure applied to the blade 26 becomes small. Therefore, even if the blade 26 is inclined downward as described later, the powder P remains on the blade 26. Although it may rotate, the upper stay 24 can prevent this. Further, the cone shell 18 vibrates up and down due to the vibration of the vibrator 16 controlled by a predetermined control unit, whereby the powder P can be prevented from adhering to the inner wall surface of the silo 2, and the powder P can be prevented. The dischargeability of can be improved.

As shown in FIG. 3, the outlet opening / closing means 12 generates an output by compressing / expanding the air supplied from a slide gate 30 for opening / closing the outlet 3 and a predetermined air supply device 41. The air cylinder 31 for driving and the transmission mechanism 32 for transmitting the output of the air cylinder 31 to the slide gate 30 are configured, and when the powder supply apparatus 1 is not in operation, the slide gate 30 is closed to prevent the powder from leaking. It is designed to prevent

As shown in FIGS. 3 and 4, the blade 26 of the screw feeder 10 according to this embodiment is inclined from the upper side to the lower side, and its appearance is similar to a shade. When the angle formed between the rotary shaft 25 and the lower surface of the blade 26 is θ (see FIG. 3), θ = 45 °.

Due to the inclination of the blade 26, the powder on the blade 26 gathers near the inner wall surface of the hopper 14. Due to the resistance between the powder and the inner wall surface generated at this time,
Since the powder slips idle on the blade 26, the powder is smoothly transferred downward as the blade 26 rotates. If the conventional blade with θ = 90 ° is used, the screw feeder rotates while the powder is placed on the blade, so the powder is not transferred downward. As a result of the research conducted by the present inventors, it has been found that the angle of repose of many kinds of powder can be allowed by setting θ = 45 °. However, the present invention is not limited to this angle, and the angle θ can be appropriately changed according to the type of powder and the like.

Further, in this embodiment, the hopper 14 has a substantially conical shape whose diameter gradually decreases from the upper part to the lower discharge port 3.
4 (a) and 4 (b), the blade 26 of the screw feeder 10 is
The spiral diameter becomes smaller as it goes downward, and the pitches L1 and L2 (see FIG. 3) between the upper and lower ends of the circumferential end become larger as it goes downward. That is, L1
<L2. With this configuration, the space formed between the blades 26 can be made uniform throughout, and the powder can be smoothly transferred downward.

Furthermore, in this embodiment, as shown in FIG. 3, one end 40a is open inside the cone shell 18 and the other end 40b is inside the upper stay 24, and the other end 40b is the air supply device. Through hole 40 communicating with 41
Are formed. By sending air from the air supply device 41 to the through hole 40 under the control of a predetermined control unit, the electric motor 15 in the cone shell 18 is
Also, the air can be blown to the vibrator 16 to cool them.

Other embodiments of the present invention will be described below with reference to the drawings. Parts having the same or similar effects as those of the first embodiment will be designated by the same reference numerals and the description thereof will be omitted. .

A discharge mechanism 50 of the powder supply apparatus according to the second embodiment will be described with reference to FIG. The screw feeder 51 in the second embodiment is configured to include a rotating body 57 in addition to the rotating shaft 55 and the blade 56 that have the same actions as the rotating shaft 25 and the blade 26 in the first embodiment. There is. The rotating body 57 has a mortar-like shape, the lower end portion thereof is fixed to the rotating shaft 55, and one end side of the blade 56 is fixed to the outer peripheral portion thereof.

The electric device accommodating portion 52 in the second embodiment has a cone cover 60 having a conical shape and a through hole 61 having the same function as the through hole 40 in the first embodiment. Support stay 6 having a recess 62 in the approximate center
3, and the electric motor 15 is arranged in a space formed by the cone cover 60 and the concave portion 62. The recess 62 is designed to fit within the mortar shape of the rotating body 57, and a bearing 58 is provided at the upper end of the rotating body 57 so that the rotating body 57 can rotate as the rotating shaft 55 rotates. Has been done.

According to the second embodiment having the above-mentioned structure, the mounting space for the electric motor 15 and the like is reduced, and therefore the size can be further reduced.

Next, referring to FIGS. 6 and 7, the discharge mechanism 70 of the powder supply apparatus according to the third embodiment will be described.
In the third embodiment, the hopper 72 has a cylindrical shape, and the blade 76 of the screw feeder 71 is
In addition to being inclined downward, FIG.
As shown in (b), the spiral diameter is the same over the entire length, and as shown in FIG. 6, the pitches L1 ′ and L2 ′ between the upper and lower circumferential end portions are the same over the entire length. ing. Even if such a hopper 72 and a screw feeder 71 are used, it is possible to obtain the same effects as those of the above embodiment.

Next, referring to FIGS. 8 and 9, the discharge mechanism 80 of the powder supply apparatus according to the fourth embodiment will be described.
In the fourth embodiment, the hopper 82 has a cylindrical shape, and the screw feeder 81 includes two spiral blades 83, 84 as shown in FIG. Is. Such a hopper 82
Even if the screw feeder 81 is used, the same effect as that of the above-described embodiment can be obtained.

As described above, in the present invention, the screw feeder can have various shapes, provided that the blade is inclined downward.

[0029]

As described above, according to the present invention, it is possible to install the screw feeder in the vertical direction, and to provide a powder supply device in which the size of the device is reduced, the cost is reduced, and the performance is improved. can do.

[Brief description of drawings]

FIG. 1 is a schematic view showing an entire powder supply device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a discharge mechanism of the powder supply device according to the first embodiment.

FIG. 3 is a cross-sectional view showing a configuration of a discharge mechanism of the powder supply device according to the first embodiment.

FIG. 4 (a) is a perspective view of the screw feeder according to the first embodiment, and FIG. 4 (b) is a bottom view of the screw feeder.

FIG. 5 is a sectional view showing a discharging mechanism of a powder supply device according to a second embodiment of the present invention.

FIG. 6 is a sectional view showing a discharging mechanism of a powder supply device according to a third embodiment of the present invention.

FIG. 7 (a) is a perspective view of a screw feeder according to a third embodiment, and FIG. 7 (b) is a bottom view of the screw feeder.

FIG. 8 is a sectional view showing a discharging mechanism of a powder supply device according to a fourth embodiment of the present invention.

FIG. 9 is a perspective view of a screw feeder according to a fourth embodiment.

FIG. 10 is a diagram showing a structure of a conventional powder supply device.

[Explanation of symbols]

1 Powder feeder 2 silos (container) 3 outlets 5,50,70,80 Ejection mechanism 10,51,71,81 screw feeder 11,52 Electric device housing 14,72,82 Hopper (guide part) 15 Electric motor 16 vibrator 23 Lower stay 24 Upper stay 25,55 rotating shaft 26, 56, 76, 83, 84 blades 31 air cylinder 40 through holes P powder

Claims (6)

[Claims] 1. A screw feeder comprising a rotary shaft rotated by a predetermined drive source and a blade having a spiral shape fixed to the outer peripheral surface of the rotary shaft, and by a rotational movement of the screw feeder, A powder supply device for discharging powder contained in a container from a discharge port provided at the bottom of the container to supply to another mechanism, wherein the screw feeder is a guide communicating with the discharge port. A powder supply device characterized in that it is arranged in a vertical direction so as to convey the powder downward from above, and the blade is inclined downward. 2. The guide portion has a substantially conical shape whose diameter gradually decreases as it approaches the discharge port, and the blade has a spiral diameter that becomes smaller as it goes downward to match the conical shape. 2. The powder feeding device according to claim 1, wherein the pitch between the upper and lower ends of the circumferential end portion becomes larger as it goes downward. 3. The screw feeder is configured to have a plurality of the blades.
The powder supply device described. 4. The inclination is 45 ° with respect to the rotation axis.
4. The powder supply apparatus according to claim 1, wherein the powder supply device has an angle of. 5. The powder supply according to claim 1, wherein the drive source and a vibrator for generating vibration are arranged above the screw feeder. apparatus. 6. The screw feeder, the drive source,
A stay for supporting at least one of the vibrators is provided, and a cooling unit for sending air to at least one of the drive source and the vibrator through a through hole formed inside the stay is provided. Claim 5
The powder supply device described.