JPS6218450B2 - - Google Patents

Description

Detailed Description of the Invention The present invention sucks and supplies raw materials from a raw material container into a hopper, and the remaining raw materials in the hopper and the remaining raw materials between the hopper discharge part and the screw are returned to the raw material container with air, and at the same time, the raw materials are returned to the raw material container in the hopper. This invention relates to a raw material reduction type hopper device that can clean the raw material.

In the conventional device, as shown in FIG. 1, a mini hopper 2 is disposed above a large hopper 1, the mini hopper 2 and a blower 3 are connected by a hose 4, and the raw material container 5 and the mini hopper 2 are connected by a hose 6. , an extraction port 1b is provided on the side of the lower discharge port 1a of the large hopper 1.
, and a extraction hose 7 is connected thereto. 8
is the screw that feeds the raw material to the molding machine.

Extraction port 1b of remaining raw material 9 in large hopper 1
The remaining raw material 9a located higher up is extracted by putting the supply hose 7 into the raw material bag 10 and extracted manually, and the remaining raw material 9b located lower than the extraction port 1b is extruded and removed by empty injection. When replacing raw materials, the raw materials adhering to the inside of the large hopper 1 are cleaned with air, but there is a drawback that the raw materials scatter around the machine.

The present invention communicates the residual material extraction hose opened at the hopper discharge port with the raw material container by switching the raw material passage switching valve, and at the same time sends compressed air into the raw material passage switching valve while back-injecting the blower into the hopper. The remaining raw material is returned to the raw material container and the inside of the hopper can be cleaned at the same time, thereby eliminating the drawbacks of the conventional method.

FIG. 2 shows an embodiment of the present invention, in which a blower 20 capable of performing reverse injection of suction and a relatively small hopper 2 are shown.
A supply hose 23 communicating with the upper part of the hopper 21 is connected to a raw material passage switching valve 25, and a discharge port 2 of the hopper 21 is connected to the upper part of the hopper 21.
1a and the raw material transfer screw 34, and is open at a rearward position.
4 is connected to a raw material passage switching valve 25. On the other hand, the raw material passage switching valve 25 and the raw material container 26 are communicated through a hose 27, the compressed air chamber 28 and the raw material passage switching valve 25 are communicated through a hose 29, and an air valve 30 is provided in between. 31 is a three-way valve within the raw material passage switching valve 25. 32 is a switch box for the blower 20. A level sensor 33 is provided within the hopper 21. In addition, the raw material supplied from the supply hose 23 is transferred to the hose 22.
A wire mesh 35 is horizontally stretched over the top of the hopper 21 to prevent it from being sucked into the hopper.

Next, the effect will be explained. Raw materials into raw material container 2
6 to the hopper 21, the select switch of the switch box 32 is turned forward, the lever 25a of the raw material passage switching valve 25 is set to the supply position, and the air valve 30 is closed. blower 20
rotates in the normal direction, and the raw material passes through the three-way valve 31 of the raw material passage switching valve 25 from the hose 27 as shown in No. 41, enters the hose 23, is sucked into the hopper 21, is discharged from the discharge port 21a, and is transferred to the molding machine by the screw 34. Transferred to the heating section. When the raw material is sucked up to the level sensor 33, the blower 20 stops. When the level falls below the level sensor 33, the blower 20 automatically rotates in the normal direction and raw material is supplied. Repeat this action.

When reducing the raw material, set the select switch of the switch box 32 to neutral. Next, the lever 25a of the raw material passage switching valve 25 is set to the discharge position, the air valve 30 is opened, and the select switch of the switch box 32 is turned in the reverse direction. As a result, the blower 20 injects the air in reverse as shown in Fig. 5, and the compressed air passes through the three-way valve 31 of the air valve 30 and enters the hose 27 as shown in Fig. 6, so that the compressed air remains in the discharge section of the hopper 21 and between it and the screw. The raw material is sucked into the residual raw material extraction hose 24 by the ejector action, passes through the three-way valve 31, is sucked into the hose 27, and is returned to the raw material container 26. At this time, the raw material adhering to the inside of the hopper 21 is also cleaned at the same time.

In the present invention, the position of the suction port of the raw material extraction hose is extremely important, but it may be located anywhere between the hopper discharge section and the screw, for example, it may be located directly below the hopper.

According to the present invention, the residual raw material extraction hose opened at the hopper discharge port and the raw material container are connected by switching the raw material passage switching valve, and the compressed air is sent into the raw material passage switching valve at the same time as the blower is injected backward into the hopper. The remaining raw material can be returned to the raw material container and the space between the inside of the hopper and its discharge part and the screw can be cleaned, so the remaining raw material can be returned with an extremely simple operation without any waste, and the amount of raw material used during blank injection can be drastically reduced. Not only is this possible, but there is no need to go to the trouble of cleaning with an air hose, etc., and there is no need for raw materials to be scattered around the machine.

[Brief explanation of the drawing]

Fig. 1 is a cutaway front view of the main part of the conventional device, Fig. 2 is a perspective view of an embodiment of the present invention, Fig. 3 is a cutaway front view of the main part of Fig. 2, and Fig. 4 is the raw material passage when feeding the raw material. FIG. 5 is a cut-away perspective view of the main part of the switching valve, FIG. 5 is a cut-away front view of the main part at the time of blower reverse injection, and FIG. 6 is a cut-away perspective view of the main part of the raw material passage switching valve at the time of raw material reduction. 20...Blower, 21...Hopper, 22,
23... Hose, 24... Remaining material extraction hose, 25... Raw material passage switching valve, 26... Raw material container, 27... Hose, 28... Compressed air chamber, 2
9...Hose, 30...Air valve, 31...
3-way switching valve, 34... Screw.

Claims (1)

[Claims] 1. A supply hose that connects the top of the hopper with a blower that can perform suction and reverse injection, and one end of the supply hose that communicates with the upper side of the hopper, and a residual material removal hose that has one end that opens between the hopper discharge section and the screw. One end of the hose connected to the raw material container and the other end of the hose connected to the raw material container are respectively connected to a three-way valve, and one end of the hose connected to the compressed air chamber is connected to the remaining raw material extraction side of the three-way valve via an air valve. By switching the 3-way valve, the supply hose and the raw material container or the residual raw material extraction hose and the raw material container can be selectively connected to each other. A raw material reduction type hopper device that is capable of returning residual raw material in the hopper to the raw material container by introducing air into the raw material container.