JPH09253476A - Powder feeding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly feed powder by preventing the powder from sticking on a screw and the wall face of a hopper and from sticking together in the hopper and preventing bridge phenomenon of the powder from occurring. SOLUTION: A supporting shaft 30 is extended in a hopper 10 and base parts of a plurality of vibrating plates 31 extending downward and base parts of vibration transmitting plates 33 extending upward are removably fixed on the supporting shaft 30. The free ends of the vibrating plates 31 are positioned up to the rotating region of a screw feeder 21 and vibration is generated by being snapped by the rotation of the screw feeder 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder supply device, and more particularly to a powder supply device that effectively prevents powder adhesion.

[0002]

2. Description of the Related Art A hopper for storing powder and a screw feeder provided under the hopper and connected to a drive source are provided, and the screw feeder is rotated by the drive of the drive source to sequentially supply the powder in the hopper. A so-called screw pressure feeding type powder supplying device is known. When supplying powder with strong adhesion in this type of device, powder adheres to the screw surface of the screw feeder, powders adhere to each other in the hopper, and powder adheres to the inner wall surface of the hopper. To do.

When the powder adheres to the screw surface, the powder also rotates together with the rotation of the screw feeder, and the powder cannot be advanced, resulting in clogging.
Further, when the powder particles adhere to each other in the hopper or when the powder particles adhere to the inner wall surface of the hopper, the powder particles may be bridged between the inner wall surfaces of the hopper to form a so-called bridge. Specifically, even if the powder in the lower part of the hopper is pumped and reduced by the rotation of the screw feeder, the powder does not flow due to the friction between the powder above and the inner wall surface of the hopper, and Bridges are created by the generation of cavities (rat holes).

Conventionally, in order to supply powder having high viscosity and adhesiveness, a spiral screw having no axis has been used in some cases. This type of screw takes a longer time until clogging occurs as compared with a screw of a type having a shaft core, but finally the clogging occurs in the spiral portion and the powder cannot be supplied. There is also a method of removing the powder adhering to the screw by vibrating the screw itself, but this requires a drive mechanism that serves as a vibration source, which not only increases the cost but also causes the powder in the hopper to reverse when vibration continues. There is a problem in that the powder is pressed and compacted, and good fluidity of the powder cannot be obtained.

According to Japanese Utility Model Laid-Open No. 2-125735, a drive device is provided above a hopper, and an elevating rod that moves in the vertical direction by the drive device is attached to the hopper, and a stirring member is attached to the elevating rod to form a block in the hopper. It describes a device that breaks down the bridge-shaped powder. Further, JP-A-5-23575 discloses that a stirring shaft is provided in a powder storage tank, a plurality of stirring blades are extended from the stirring shaft, and the stirring blade is rotated by rotating the stirring shaft to stir the powder. The device to do is described.

Further, in Japanese Patent Application Laid-Open No. 4-118041, a hopper is formed of a flexible material, and a hard annular body that is connected to a drive source and surrounds the hopper is provided, and the rigid annular body moves to be flexible. A device is described for breaking the bridge of powder by changing the shape of the sex hopper. In addition, 60
No. 39333 discloses a device in which jet nozzles are arranged in a hopper and air is jetted to destroy the bridge. ,

[0007]

However, the actual Kaihei 2-1.
The devices disclosed in Japanese Patent No. 25735 and Japanese Patent Application Laid-Open No. 5-235575 require not only a device for driving an agitator such as a stirring member and a stirring blade, but also a large amount of powder is moved by the agitator. There is a drawback in that the powder in a place other than the drive region is consolidated. In addition, in the device disclosed in Japanese Patent Laid-Open No. 4-118041,
Similarly, a drive is required and powder compaction can occur. Further, the device described in Japanese Utility Model Laid-Open No. 60-39333 requires a mechanism for injecting air,
Further, since the air flow acts on the local part of the powder, there is a problem that the bulk density of the powder cannot be made constant.

Therefore, the present invention has a hopper for storing powder and a screw feeder provided under the hopper and connected to a drive source, and the screw feeder is rotated by the drive of the drive source to remove the powder in the hopper. In a powder supply device that sequentially supplies, without attaching a drive device separately, adhesion of the powder to the screw, adhesion of the powder in the hopper,
An object of the present invention is to provide a powder supply device capable of effectively preventing the powder from adhering to the wall surface of the hopper and bridging the powder in the hopper, thereby enabling smooth powder supply.

[0009]

To achieve the above object, the present invention has a hopper for storing powder and a screw feeder provided under the hopper and connected to a drive source. In the powder supply device for sequentially supplying the powder in the hopper by rotating the screw feeder by the driving of the support shaft 30 extending in the hopper 10.
A vibration plate 31 extending from the support shaft 30 into the rotation range of the screw feeder 21, and a vibration transmission plate 3 standing upright from the support shaft 30 toward the upper part of the hopper 10.
The powder supply device 1 having the number 3 is provided.

Here, it is preferable that the support shaft 30 is extended to a lower portion inside the hopper 10. Further, the diaphragm 31
It is preferable that the vibration transmission plate 33 is detachably fixed to the support shaft 30. Further, it is preferable that the support shaft 30 is provided slidably in the axial direction.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A powder supply apparatus according to an embodiment of the present invention will be described with reference to FIGS. This powder supply device is used, for example, to supply a powdery mold release agent to a die casting machine.

In FIG. 1, the powder supply apparatus 1 has a hopper 10 and a feeder section 20 provided below the hopper 10. The hopper 10 is in the shape of an inverted quadrangular pyramid, the upper part thereof is a powder charging port 11, and the powder P is accommodated therein. The inside of the hopper 10 communicates with a dryer (not shown) for drying the powder P, and an air inlet (not shown) for promoting discharge of the powder is formed as necessary. The hopper 10 may have an inverted conical shape.

The feeder unit 20 is connected to a screw feeder 21 provided at a position facing the lower end opening 12 of the hopper 10 and a rotary shaft 21a of the screw feeder 21, and a drive motor 22 which is rotationally controlled by a control box (not shown). Have and. An electromagnetic shutter 23 is provided on the powder outlet side of the screw feeder 21, and a hose for carrying powder (not shown) is connected to the electromagnetic shutter 23. Since high-pressure air flows in the hose, the electromagnetic shutter 23 prevents the powder P discharged by the screw feeder 21 from flowing backward in the screw feeder 21 by this high-pressure air and entering the hopper 10.

At a lower position in the hopper 10, a support shaft 30 extending substantially parallel to the rotary shaft 21a of the screw feeder 21 is installed. Then, one end portion of the plurality of diaphragms 31 extending downward from the support shaft 30 has the diaphragm fixing screws 3
It is removably attached to the support shaft 30 by means of 2. The free end of each diaphragm 31 is located within the rotation range of the screw feeder 21. Therefore, when the screw feeder 21 rotates, the free end of the vibration plate 31 can come into contact with the screw feeder 21.

Further, one end portions of a plurality of vibration transmitting plates 33 extending upward from the supporting shaft 30 are detachably attached to the supporting shaft 30 by a vibration transmitting plate fixing screw (not shown). Therefore, the vibration transmitting plate 33 is located in the powder P contained in the hopper 10. Here, the vibration plate 31 and the vibration transmission plate 33 are formed of an elastic material that exhibits an elastic restoring force (spring property).

In the above structure, the powder P charged through the powder charging port 11 is stored in the hopper 10. Drive motor 2 based on a drive signal from a control box (not shown)
When the screw feeder 21 is rotated by driving 2, the vibrating plate 31 is repelled by the screw surface, elastically deforms and strikes the screw surface, and the impact removes the powder adhering to the screw surface. 2 and 3 show only one diaphragm 31 for simplification, the rotation of the screw feeder 21 causes the free end of the diaphragm 31 to come into contact with the ridge portion of the screw feeder 21 and the position indicated by the broken line in FIG. Oscillates while elastically deforming in the direction of the solid line,
It is flipped over the mountain at the critical point in the direction of the broken line. That is, the vibrating plate 31 is repeatedly repelled between the solid line position and the broken line position, and the vibration at that time separates the powder from the screw surface,
As shown in FIG. 3, a state in which no powder adheres is obtained. Note that FIGS. 2 and 3 show only the powder adhered to the screw, and the powder fed under pressure by the screw feeder 21 is not shown.

Further, as shown in FIG. 1, the vibration transmitting plate 33 also shakes at the same time due to the vibration of the vibrating plate 31 caused by the rotation of the screw feeder 21, so that the powder P in the hopper 10 is vibrated. Therefore, the bridge of the powder P formed in the hopper 10 is destroyed. Therefore, the powder can flow smoothly to the lower part of the hopper 10, and the powder P is reliably transferred by the screw feeder 21.

The present invention is not limited to the above-described embodiment, but various modifications can be made. For example, various kinds of vibration plates 30 and vibration transmission plates 33 having different spring forces are prepared, and the vibration plates 30 and vibration transmission plates 33 are selectively used according to the type and amount of powder, and the vibration plates and the vibration transmission plates are supported. A more effective powder adhesion preventing effect can be obtained by adjusting the number of attachments to the shaft. In addition, if necessary, a mechanism that allows the support shaft 30 to slide in the axial direction is added, and the support shaft 30 is reciprocally moved in the axial direction during the powder supply operation, so that the powder in the hopper is twisted. It is possible to give vibration to a wide range.

[0019]

According to the powder feeding apparatus of the first aspect of the present invention, since the vibrating plate is extended into the rotation range of the screw feeder, the vibrating plate is repelled by the rotation of the screw feeder and the vibrating plate is obtained. The vibration of the screw causes the screw surface to vibrate. Therefore, the powder adhering to the screw surface can be easily removed, the powder can be effectively prevented from adhering to the screw surface, and the powder can be smoothly advanced. Further, due to this vibration, the vibration transmission plate standing upright toward the upper part of the hopper also vibrates, so that the powder in the hopper is vibrated and the flow of the powder in the hopper is promoted. Therefore, it is possible to weaken the adhesive force between the powders accumulated in the hopper and prevent the generation of bridges due to the powders. Since the vibration plate and the vibration transmission plate are interlocked with the screw, they do not constantly vibrate, and only intermittent weak vibrations occur only when powder is supplied. The powder does not move greatly in the space inside the screw or in the hopper,
The powder in the hopper is not consolidated, and the powder does not clump. Further, it is not necessary to separately provide a drive device for vibrating the diaphragm and the vibration transmitting plate.

According to the powder supply device of the second aspect of the present invention, the diaphragm can be vibrated with certainty. That is, because of the weight of the deposited powder, the fluidity of the powder at the bottom of the hopper is inferior to that of the powder at the top of the hopper.
The motility of the diaphragm that abuts the screw located at the bottom of the hopper tends to be impaired, but since the support shaft is provided at the bottom of the hopper, the diaphragm will be located near the screw feeder, By virtue of the contact with the rotating screw surface, the vibration of the diaphragm can be secured, and strong vibration can be generated in the diaphragm. Therefore, the powder adhering to the screw surface can be reliably removed.

According to the powder feeder of claim 3 of the present invention, since the vibrating plate and the vibration transmitting plate are detachable from the support shaft, the properties of the powder, such as lumpiness, adhesiveness, weight, The optimum diaphragm can be used by changing the number of diaphragms and vibration transmitting plates according to the amount of powder, or by changing the flexural property by changing the materials.

According to the powder feeder of claim 4 of the present invention, since the support shaft is slidable in the axial direction,
Vibration can be transmitted over the entire area of the hopper, and a sufficient powder adhesion preventing effect can be obtained.

[Brief description of drawings]

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

FIG. 2 is a schematic side view showing a feeder unit of the powder supply device according to the embodiment of the present invention.

FIG. 3 is a schematic side view showing a feeder portion of the powder supply device according to the embodiment of the present invention, showing a state in which powder is separated from the screw surface.

[Explanation of symbols]

 1 Powder Supply Device 10 Hopper 21 Screw Feeder 30 Support Shaft 31 Vibration Plate 33 Vibration Transmission Plate

Front page continuation (72) Inventor Kazuhiko Watanabe Ryobi Co., Ltd. 762, Mesaki-cho, Fuchu-shi, Hiroshima

Claims (4)

[Claims] 1. A hopper that stores powder, and a screw feeder that is provided below the hopper and that is connected to a drive source. The screw feeder is driven by the drive source to rotate the powder inside the hopper. In a powder supply device for sequentially supplying a body, a support shaft extending into the hopper, a vibration plate extending from the support shaft into a rotation range of the screw feeder, and an upper portion of the hopper from the support shaft. A powder supply device, characterized in that it is provided with a vibration transmission plate that is erected toward. 2. The powder supply apparatus according to claim 1, wherein the support shaft is extended to a lower portion inside the hopper. 3. The powder supply device according to claim 1, wherein the vibration plate and the vibration transmission plate are detachably fixed to the support shaft. 4. The support shaft is provided so as to be slidable in its axial direction.
The powder supply apparatus according to any one of 1.