JPS6032018Y2 - Device for transferring powder and granular materials between two chambers with a pressure difference - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a device for transferring powder or granular material between two units in which there is a pressure difference between gas or liquid.

For example, a rotary valve or a Kinyon pump is known as a device for moving powder or granular material between two chambers where there is a pressure difference while maintaining a sealed state between the two chambers.

However, rotary valves have the disadvantage of poor sealing properties due to their structure, and Kinyon pumps have the following disadvantages.

In other words, in the Kinyon pump, the pitch of the screw blades overhanging inside the right cylindrical pipe is made narrower toward the discharge port, and when the screw blades rotate at high speed, powder and granules are transferred between the screw blades. By consolidating
The inside of the cylindrical tube is sealed with the powder and granules compacted in this way, and the granules are pushed out toward the discharge port of the cylindrical tube, so in order to obtain a complete sealing effect, the screw blades must be In addition to requiring a large amount of horsepower due to the high speed rotation, it also had the disadvantage that the amount of powder transported cannot be adjusted because a certain amount of powder and granules must be continuously fed at a certain speed.

Therefore, this invention aims to provide a device for transferring powder and granular materials that does not have the above-mentioned drawbacks. A screw feeder is constructed in such a way that powder and granules introduced into an inlet opened at an appropriate position in a cylindrical tube are discharged from the end of the cylindrical tube, and a partition wall between the two bases with a pressure difference is used. The powder and granular material between the two screw feeders with a pressure difference is installed horizontally through the screw feeder, and a damper is provided at the discharge port of the screw feeder, which is elastically energized in a direction that always closes the discharge port. In the transfer device, the discharge side of the screw shaft is formed into a tapered shape, and the portion of the cylindrical tube between the vicinity of the tip of the screw shaft and the discharge port is formed into a reversely tapered diverging tube. The apparatus for transferring powder and granular materials is characterized by:

To explain the embodiment with reference to the figures, in this embodiment, the inside of the storage tank 1 is kept at a higher pressure than the atmosphere outside the tank (atmospheric pressure),
For example, when implemented as a device for transferring powder or granular material such as wood flour, that is, as a device for supplying the powder or granular material into the high-pressure storage tank 1 under a sealed condition, in the figure, 2
is a discharge box connected to the upper part of the storage tank 1; 3 is a screw feeder horizontally suspended through the wall of the discharge box 2; This screw feeder 3, which consists of a tube 4 and a screw shaft 5 horizontally suspended in the cylindrical tube 4 in an overhanging manner, is fed into an input port 6 made at an appropriate position in the cylindrical tube 4 outside the tank 1. The granular material is configured to be discharged from a discharge lower at the end of the cylindrical pipe 4 opened into the discharge box 2, and a swing damper is installed at the end of the cylindrical pipe 4 opened into the discharge box 2. 8 are arranged.

This swing damper 8 has a shaft 9 to which it is fixed, which is rotatably supported by the discharge box 2, and an arm 10 is attached to the portion where the shaft 9 protrudes outside the discharge box 2. The swing damper 8 is always urged in a direction to close the 4 ends of the cylindrical pipe by a spring 12 stretched between the tip of the arm 10 and the bracket 11 fixed to the discharge box 2. ing.

13 is a screw for adjusting this biasing pressure.

In the figure, 14 is a hopper 15 connected to the input port 6, and 16 is a bearing for the screw shaft 5.
The driving force is inputted to a drive wheel 17 fitted on the shaft end of the screw feeder 3. It is structured as follows.

That is, the screw feeder 3 has its screw shaft 5
is composed of an attached shaft portion 5a and a conical shaft portion 5b, and the discharge side of the conical shaft portion 5b is formed into a tapered shape, and the screw blade 18 also has the same diameter in the attached shaft portion 5a. However, in the conical shaft portion 5b, the diameter of the blade 18 is gradually reduced.

Further, the tip of the screw shaft 5 is formed into a tapered shape,
A certain distance a is provided between the end of the cylindrical tube 4 and the discharge lower, and the cylindrical tube 4 has a portion with the same diameter where the screw shaft 5 is located inside. The above-mentioned interval a portion on the discharge lower side, which is formed in the straight pipe 4a but where the screw shaft 5 is not located inside, is shaped like a truncated cone with a reverse taper toward the discharge lower side. It is formed in the wide-divergent tube 4b.

Since the granular material transfer device according to this invention has the above-described configuration, when the granular material is introduced from the hopper 14 into the inlet 6 of the screw feeder 3, the granular material introduced into the inlet 6 is transferred. enters the straight pipe 4a of the cylindrical pipe 4 and is sent toward the discharge lower direction by the blades 18 of the screw shaft 5 rotating inside the pipe. Since it is composed of the attached shaft portion 5a and the conical shaft portion 5b, the attached shaft portion 5a
In this case, the granular material is simply transported forward, but
At the conical shaft portion 5b at the tip, the discharge lower is closed by the swing damper 8 and the shaft becomes tapered, so that the powder and granules that have reached the tip do not form a hollow shape, but instead cover the entire cross section of the tube. The powder is uniformly dispersed and compacted, and a compressed tank A of the powder is formed in the vicinity of the tip of the conical shaft portion 5b and within the wide-spread pipe 4b between the discharge lower.

The powder compacted in the diverging tube 4b in this way is pushed by the blades 18 of the screw shaft 5 while being kept in a compacted state, and pushes the swing damper 8 slightly against the bias of the spring 12. It opens to form a gap in the discharge lower, from which an amount corresponding to the feed amount of the screw blade 18 is discharged into the discharge box 2.

Therefore, according to the device of this invention, the inside of the screw feeder 3 is obstructed by the compressed layer A of the powder compacted inside the diverging tube 4b, and as a result, the compressed layer A increases the pressure. The powder and granules are transferred between the two chambers (while maintaining a seal between the two chambers with a difference, that is, the inside of the storage tank 1 and the outside of the storage tank 1), and the device of this invention Since the screw shaft 5 is composed of an auxiliary shaft portion 5a that serves as a mere transport and a conical shaft portion 5b that serves as a transport and consolidation role, the screw shaft 5 can be moved at a low speed suitable for the purpose of transporting powder and granules. Even if it is rotated, a sealing layer consisting of the compressed layer A of powder and granules can be formed in the divergent tube 4b, and the wear of the screw shaft 5 is small, and by adjusting the force of the damper 8 ,
The desired amount of powder can be transferred with less power than conventional Kinyon pumps.

Moreover, the compacted layer A of the powder material compacted in the diverging tube 4b in this way is in a hollow compacted state in which the compacted state in the center is less dense than in the part near the pipe wall, as described above. Since the pipe is made completely solid and the entire cross section of the pipe is compressed to a uniformly compacted state, a perfect sealing layer can be obtained. Since the reverse taper with the lower side widened has a slope, the compressed layer A formed in the diverging tube 4b does not generate large frictional resistance with the tube wall in the direction of discharging the powder and granules. The frictional resistance between the pipe wall and the pipe wall does not vary greatly depending on the type of powder, moisture content, weather conditions, etc., as in the case of attached pipes.

That is, in the transfer device of this invention, the strength of the specific density of the compressed layer A formed in the divergent tube 4b is controlled by the swing damper 8.
Since it can be easily and accurately controlled by adjusting the biasing spring 12 of the swing damper 8, the fluctuation of the frictional resistance can be sufficiently absorbed by the biasing spring 12 of the swing damper 8.
Powder and granular materials can be smoothly and continuously transferred over a long period of time without causing problems such as destruction of the compacted state due to a decrease in frictional resistance with the pipe wall surface, or overload stoppage due to an increase in frictional resistance. It is something.

In addition, the discharge lower side of the cylindrical pipe 4 is a reversely tapered diverging pipe 4b.
By doing so, we not only reduce the frictional resistance between the tube wall and the granular material as described above, and also reduce the influence of its fluctuations, but also obtain the following wedge effect. .

In other words, the wide-spread pipe 4b has a vertical slope with respect to the direction in which the powder and granules are discharged, but in the opposite direction, the compressed layer A becomes wedge-shaped, so that the powder and granules are returned in the direction in which they are returned. is difficult to move.

Therefore, in the transfer device of this invention, even if the drive of the screw shaft is stopped, the wedge-shaped compressed layer A is kept in a compressed state by the swing damper 8, and the seal is not destroyed.

In addition, in the above embodiment, an example was shown in which the damper is constituted by a swing damper 8 whose one end is pivotally supported, but the damper is not limited to a swing type damper, and in other embodiments, This may be provided so as to be slidably supported in the direction of the discharge lower, and although the above embodiment has been explained assuming that the inside of the storage tank 1 is under high pressure, the powder and granular material transfer device according to this invention It goes without saying that this can be carried out even when the pressure on the storage tank 1 side is low.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of a powder or granular material transfer device according to this invention. 1... Storage tank, 3... Screw feeder, 4... Cylindrical pipe, 4a... Straight pipe, 4
b... Wide diverging tube, 5... Screw shaft,
5a... Attached shaft part, 5b... Conical shaft part, 6... Input port, 7... Outlet port,
8... Swing damper, 12... Spring.

Claims (1)

[Scope of utility model registration request] A screw feeder consisting of a cylindrical tube and a screw shaft disposed horizontally within the cylindrical tube, and configured so that powder and granules introduced into an inlet opened at an appropriate position in the cylindrical tube are discharged from the end of the cylindrical tube. is suspended horizontally through the partition wall between the two units where there is a pressure difference, and at the discharge port of this screw feeder,
A device for transferring powder or granular material between two units with a pressure difference, the device comprising a damper that is elastically biased in a direction that always closes the discharge port, wherein the discharge side of the screw shaft is
A device for transferring powder or granular material, characterized in that the cylindrical tube is formed into a tapered shape, and the portion of the cylindrical tube between the vicinity of the tip of the screw shaft and the discharge port is formed into a reversely tapered diverging tube.