JPS6224490Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a feeding device for feeding a mixture of solid or synthetic resin powder, carbon fiber, etc., which is particularly easy to separate and has extremely poor flow characteristics, to an extruder or the like. Containers such as hoppers, which have small diameter holes in a portion (generally the bottom), are used as feeding devices in a wide range of industrial fields.

In the case of particles with good fluidity such as synthetic resin pellets, a container with a hole in the bottom is usually sufficient and no other attached mechanism is required. In addition, when forcibly feeding into an extruder or the like or when maintaining a constant supply amount, a screw conveyor may be further connected to the bottom.

Furthermore, in cases where the fluidity is slightly poor and bridges are formed in the hopper, it is possible to install an agitator in the hopper, install a rubber tube in a part of the hopper and expand it with air pressure, apply vibration, or Various measures have been taken to prevent bridges, such as installing partitions made of slippery materials.

However, for example, materials such as a mixture of synthetic resin powder and non-convergent short fibers such as glass or carbon, which are very easy to separate, have a small bulk specific gravity, easily change volume under pressure, and have extremely poor fluidity. The various devices mentioned above are completely ineffective for continuous supply. In other words, such substances with extremely poor fluidity are not discharged at all from the hopper, which is simply discharged by gravity, and even if the substance at the bottom is forcibly discharged, a bridge forms at the top, making continuous discharge impossible. It is.

Adding stirring, vibration, etc. to destroy the bridge causes separation of the contents and is completely impractical. Furthermore, applying a slight pressure using a rubber tube or the like will be absorbed by the volumetric contraction of the contents in the vicinity, and will be completely powerless to expel the contents.

An object of the present invention is to provide a feeding device that can continuously and steadily feed mixtures that could not be handled using conventional techniques.

The device of the present invention is located inside the hopper container, and
An ejection screw that has the function of forcibly transferring the contents in the vicinity to the ejection port, and a piston-like function that has the function of forcibly transferring the contents toward the ejection screw to the vicinity of the screw and pressing it against the side of the screw. This is a feeding device characterized in that it also has a movable plate.

That is, with the screw of the present invention, the contents near or within the screw quickly reach the discharge port and are further discharged to the outside.

However, this function alone is insufficient for the contents with extremely poor fluidity as mentioned above. That is, in this case, a cylindrical space is created in the screw portion, and further discharge becomes impossible.

The piston-shaped movable plate, which is the second feature of the present invention, moves the contents of the part that does not touch the screw to the screw part, and then presses it against the side of the screw to feed the contents into the screw and continuously. Allow for evacuation. Furthermore, this pressing increases resistance to the contents within the screw, facilitating ejection of the screw contents.

Further, if the first feature is that the screw is not provided and the contents are simply pushed toward the discharge port, the contents are only compacted near the discharge port and are not discharged.

As described above, the device of the present invention has two distinctive functions that effectively function, thereby making it possible to continuously supply substances that have extremely poor flowability and are easy to separate, which conventional devices could not handle at all.

The screw, which is the first feature of the present invention, is of a normal shape. Preferably, a screw in the form of a coiled spring is used.

Also, this type of screw is further than the discharge port.
When extended into the subsequent cylinder and used as a force feeder, it exhibits a unique effect.

In a screw designed to have appropriate spring elasticity, if the feed rate becomes excessive, the feeder outlet pressure increases and the screw contracts. As a result, the screw spacing within the feeding device becomes narrower.
The biting amount decreases. As a result, oversupply will be eliminated.

Such a mechanism automatically controls the supply amount and pressure.

The second distinctive mechanism, the piston-like movable plate, is extremely easy to separate and can move poorly flowing contents toward the ejection screw. In this case, measures such as setting up multiple units for continuous operation may be added.

The present invention will be described below based on drawings showing embodiments.

FIG. 1 shows an example of a piston-shaped movable plate 10 of the present invention.

In the figure, 11 is a screw for ejection, and 12 is a movable plate for pushing. In this case, it is preferable that the container 13 itself rotates so that the contents are evenly pressed against the screw. There is a discharge port at the bottom of the discharge screw, which passes through the force feeder section 17 to the extruder 16.
is supplied to.

The discharge screw 11 inside the container is a helical spring-like screw, and the upper part is connected to the shaft 1.
It is connected to a motor etc. via 8. The bottom part is 1
It reaches up to 7 and doubles as a force feeder.

FIG. 2 is a side view of the device shown in FIG. 1.

As mentioned above, in this shape, discontinuity occurs at the end of the stroke, so it is preferable to use a plurality of strokes, for example as shown in FIG. 3, and to use them alternately. 20 and 20' in FIG. 3 are partition plates for alternate use. In addition, in order to quickly fill the container 13, for example, as shown in FIG.
It can also be made 3".

Regarding the pushing cycle of the piston-like movable plate, if the cycle is extremely long, the pulsation cannot be absorbed by the force feeder, and if the cycle is extremely short, it becomes vibrating, and the content is not supplied from the upper part during one cycle. It means you won't make it in time.

In applications where pulsation is undesirable for the above reasons, it is preferable to use a period as short as possible, and in the case of contents that are difficult to fall or easily separate, a period as long as possible should be used. Usually, this period is preferably about 0.5 seconds to 10 seconds.

If the stroke length is too short, the pushing force will be absorbed, so it is necessary to adjust the stroke length appropriately. The stroke length is preferably about 1/10 or more of the diameter in the case of contents with large volume shrinkage such as non-convergent fibers. However, for contents with small shrinkage, about 1/10 or less is sufficient. From the viewpoint of durability and pushing ability, it is preferable to move the wall surface by using a plate-like material such as a synthetic resin as in this example.

The screw 11 is particularly a force feeder section 17.
When utilizing the quantitative property of the above, it is preferable to design based on the necessary pressing pressure.

Generally, the pitch of the screw should be larger than the diameter of the screw pitch, since relatively large, weakly convergent agglomerates are usually formed in the case of contents with poor flowability that require the apparatus of the present invention.

Above, we have described a feeding device that is particularly effective for mixtures containing non-converging fibers. However, when transferring such raw materials or raw materials that form pilling due to long-term stirring, such as raw materials containing convergent fibers, the feeding device is Preferably, the mouth part is designed as follows.

For example, when the transfer machine is an extruder, conventionally, a hole provided in the barrel 14 is used for feeding, and so that the formation of a bridge in this part or the lack of biting into the screw 15 does not impede extrusion.
A large opening area is used, more than 1 times that of a screw pitch, especially in natural feeds.
1.5 to 2 times larger holes were used.

However, in such a design, a part of the raw material remains for a long time at the feed opening, and in the case of raw materials containing fibers, pilling occurs, which hinders the feeding.

In addition, in such a supply port, most of the actual supply is performed at the X section in Fig. 5, so it is necessary to shift the raw material within the supply port for supply.
Fibrous raw materials have a high resistance to displacement, making it impossible to supply them.

To solve this problem, contrary to conventional wisdom, it is necessary to use a small supply port, for example, 0.8 screw
A pitch level is preferable. Further, it is preferable that the opening shape be matched to the actual biting.

Some examples of these are shown in FIGS. 6A, B, and C.

Further, when a bridge is formed using this material, a force feed is also preferable. In particular, a force feeder whose tip reaches close to the screw of the extruder is preferable in order to eliminate the feed defects caused by the difference in raw material supply speed described above. This idea is not limited to extruders.
Effectively used in general transfer machine connections.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional view showing an example of a feeding device using a piston-like movable plate according to the present invention, FIG. 2 is a schematic cross-sectional view of the device shown in FIG. 1, and FIG. The figure is a sectional view showing an example in which multiple containers are connected and used alternately in the apparatus shown in Figure 1, and Figure 4 is an example in which the partition plate used in Figure 3 is divided into two. FIGS. 5 and 6 are schematic explanatory views showing an example of the design of the supply port to the transfer machine in the case where the feed material forms fluff. 12... Piston-shaped movable plate, 11... Screw.

Claims (1)

[Scope of utility model registration request] A discharge screw located inside the hopper container, one end of which reaches or penetrates the contents discharge port, and which can transport adjacent contents to the outside of the discharge port by rotating; 1. A feeding device for a mixture of synthetic resin powder and short fibers, comprising a piston-like movable plate that can be forcibly transferred.