JPH1148347A - Method and apparatus for feeding foamed beads - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent foamed beads from causing a bridging phenomenon in a granulation pipe. SOLUTION: The following eccentric air flow capable of injecting an eccentric air flow for imparting a swirling flow to the foamed beads is injected into a granulation pipe 3 which connects the foamed beads supply tank 2 and a mold cavity 1 and feeds the foamed beads. Install air injection parts. This air injection component is composed of a cylindrical body 4 having an injection hole 41 eccentrically provided on a side wall and a housing 5 surrounding the cylinder 4 and forming a space 52 for supplying air to the injection hole 41. A cylindrical body 4 is fitted into a cylindrical housing 5 from above at least, and a space 52 having an air supply hole 51 is formed from an inner wall of the housing and an outer wall of the cylindrical body 4. The upper connection fitting 6 is fitted and fixed via an O-ring 42 and assembled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of feeding foam beads for feeding foam beads as a raw material from a foam bead supply tank to a mold cavity, which is one of the operations of a foam molding machine. The present invention relates to improvement of a granulating device.

[0002]

2. Description of the Related Art Conventionally, in a molding apparatus used for a foam molding method of a foam molded product made of expanded polystyrene resin or the like, first, as shown in an illustration of FIG. 3, a cavity 1 in which a foam product is filled and molded is formed. As shown, a male-type convex inside 11 and a female-type concave inside 12
Are arranged to face each other. The insides 11 and 12 are provided with countless vent holes so that the heating steam can pass therethrough. In addition, these inside 11, 1
On the back side of 2, to supply utilities such as steam,
Alternatively, chambers 13 and 14 for discharging are formed. In such a foam molding apparatus, expandable raw material beads preliminarily foamed (hereinafter simply referred to as foam beads)
After filling into the cavity 1, steam for heating is introduced from the chambers 13 and 14, and the foam beads are heated and fused to produce a foam molded article having a predetermined shape.

[0003] In such a molding method, in order to fill the foam beads into the cavity 1, the foam beads as a pre-foamed raw material are temporarily stored in a supply tank 2 as illustrated in FIG. In the molding process, the cavity 1 in the mold is passed through the granulating pipe 3 connected to the bottom.
Sent to. In this case, supply tank 2 is set to 0.5 to
Apply a pressure of about 1.0 kg / cm ² , slightly reduce the pressure in the cavity 1 and provide a differential pressure of about 0.2 kg / cm ² ,
An airflow flowing from the supply tank 2 toward the cavity 1 is formed in the feed pipe 3 having an inner diameter of about 25 mm. Then, along with the flow of the air current, foamed beads preliminarily foamed into a substantially spherical or dumpling shape having a diameter of 1 to 8 mmφ are fed into the cavity and filled. Note that a filler 31 is provided on the cavity 1 side of the granulation pipe 3, and pressurized air is introduced into the filler 31 to promote filling of the expanded beads.

[0004] In such an apparatus for feeding foamed beads using a granulating pipe, it is necessary to prevent the foaming beads from causing a bridging phenomenon in the granulating pipe to block the pipe.
It is important to ensure smooth feeding, and in addition to selecting the type of sending beads, particle size, length of sending pipe, height difference, degree of differential pressure between both ends, etc. In many cases, an intermittent supply device 21 is provided at the outlet of the supply tank 2.

The intermittent supply device 21 is, for example, shown in FIGS.
As illustrated in FIG.
The supply path to the inlet opening 32 is repeatedly opened, closed, opened and closed by rotating the disk 22 having a plurality of openings 23 provided around the disk 22 and rotating the disk 22. ,
The flow of expanded beads is intermittently repeated with the flow of air. Even if a bridging phenomenon starts to occur somewhere in the granulation pipe 3, the bridging effect is intended to be eliminated before the intermittent impact increases the bridging phenomenon. -ing

[0006] By the way, there are foamed beads made of polyolefin as a raw material in addition to polystyrene as a resin type of foamed beads. In the case of foamed beads made of this polyolefin, the structure is soft and the coefficient of friction is so high that it is sticky. Therefore, there is a problem that a bridging phenomenon easily occurs even in a slightly bent place in the granulation pipe 3.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem of clogging in the foaming of foam beads by an operation principle different from that of the intermittent supply device. Provided are a method and an apparatus for feeding foamed beads, which can make the foamed beads less likely to cause a bridging phenomenon.

[0008]

First, a method for feeding foamed beads of the present invention, which has been made to solve the above problems, comprises:
A method for feeding foamed beads from a foamed bead supply tank of a foaming molding machine to a mold cavity, wherein a swirling flow is applied to foamed beads that move together with an airflow in a grain feeding flow path. The method for feeding foam beads of the present invention is embodied as a method for imparting a swirl flow, as one mode of imparting the swirl flow, by injecting an eccentric air flow into a grain feed conduit to impart a swirl flow. Can be.

Next, the apparatus for feeding foamed beads of the present invention, which has been made to solve the above-mentioned problem, connects a foamed bead supply tank of a foaming molding machine and a mold cavity to feed foamed beads. The present invention is characterized in that air injection means capable of injecting an eccentric air flow for imparting a swirling flow to the expanded beads is interposed in the grain pipe. As one mode of the foamed beads feeding apparatus of the present invention, an air injection unit supplies air to the injection hole by surrounding the cylinder with the injection hole eccentrically provided on the side wall and surrounding the cylinder. And a housing that forms a space for the air injection.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a method for feeding foamed beads of the present invention will be described with reference to FIGS. .
In the present invention, a foaming bead is eccentric to give a swirling flow to the foaming bead 3 by connecting the foaming bead supply tank 2 and the mold cavity 1 of the foaming molding machine shown in FIG. It is constituted by attaching air jet means capable of jetting an air flow. This air injection means is shown in FIG.
2, the injection hole 41 is eccentrically provided on the side wall of the cylindrical body 4 and the cylindrical body 4 is surrounded by the injection hole 41.
And a housing 5 forming a space 52 for supplying air to the housing.

The air jetting part will be described in further detail. A cylindrical body 4 is fitted into a cylindrical housing 5 from above, and a space provided with an air supply hole 51 from the inner wall of the housing and the outer wall of the cylindrical body 4. 52 is formed, and the upper connection fitting 6 is fitted and fixed via the O-ring 42, thereby obtaining the illustrated air injection component. Here, the upper connection part 61 is connected to the supply tank 2, and the lower connection part 53 is connected to the granulation pipe 3.

The cylinder 4 used here is the same as that shown in FIG.
25mm, thickness 3mm, length 4
It is a brass cylinder having a height of about 0 mm, a flange having a height of about 3 mm at both ends thereof, and a single or a plurality of through holes 41 having an inner diameter of about 0.5 to 1 mm on the side wall thereof (FIG. 2). In the present invention, four injection holes are shown, and the penetration direction of the holes is eccentric from the axis of the cylindrical body 4 toward the inner wall side.

In the present invention, after the cylindrical body 4 having the injection holes 41 is assembled into the air injection part as described above, pressurized air of an appropriate pressure is supplied to the space 52 from the outside through the air supply holes 51. In this case, the air is injected from the injection hole 41 into the cylindrical body 4 as an injection flow. However, since the injection direction is eccentric toward the inner wall, the swirling flow as shown by the dotted line in FIG. Is formed.

Thus, a swirling flow is applied to the foam beads sent out from the supply tank 2 together with the air flow. According to the granulating method and the granulating apparatus of the present invention, the foam beads are formed in the granulating pipe 3. In this case, since it moves while turning along with the airflow, it is possible to obtain not only an effect that it is difficult to form a bridge, but also a remarkable effect that blockage of the particle feed pipe 3 hardly occurs.

In this case, the pressure of the jet air is balanced to the value of the pressurized pressure of the supply tank plus about 0.5 to ¹ kg / cm ^2. It is preferable from the range which does not give an obstacle. Further, the effect of the swirling flow thus obtained is sufficiently exhibited up to the length of 3 to 4 m of the feed pipe, but when the length is long, a plurality of pipes may be attached as needed.

In addition, since a conventional flexible pipe used conventionally can be applied as it is to the granulation pipe itself used in the present invention, equipment cost and running cost do not increase. Further, the conventionally used intermittent supply device 21 (FIG. 3) can be omitted.

[0017]

According to the method for feeding foamed beads of the present invention, it is possible to prevent a defective closing of a granulation pipe by a simple operation of imparting a swirling flow to the foamed beads. In addition, the apparatus for feeding foamed beads of the present invention can impart a swirling flow to the foamed beads by means of an air-jetting part having a simple structure, can prevent blockage defects of the pipes for feeding beads, and can reduce equipment costs. There is an excellent effect that the running cost does not increase. Therefore, the present invention has a very large industrial value as a method and apparatus for feeding foamed beads in which the conventional problems are solved.

[Brief description of the drawings]

FIG. 1 is a sectional view of an essential part for explaining an air injection component of the present invention.

FIG. 2 is a perspective view of a main part showing a cylindrical body of the present invention.

FIG. 3 is a layout illustration of a conventional foam molding machine centered on a granulation pipe.

FIG. 4 is a plan view of a main part of a disk component of the conventional intermittent supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cavity 2 Supply tank 3 Granulation pipe 4 Cylindrical body 5 Housing 41 Injection hole 51 Air supply hole 52 Space

Claims (4)

[Claims] 1. A method for feeding foam beads from a foam bead supply tank of a foam molding machine to a mold cavity, wherein a swirling flow is applied to foam beads moving together with an air flow in a grain feed channel. Method for sending foam beads. 2. The method for feeding foam beads according to claim 1, wherein an eccentric air flow is jetted into the feeding channel to give a swirling flow. 3. An eccentric air flow for imparting a swirling flow to the foamed beads can be injected into a granulation pipe for connecting the foamed beads supply tank of the foam molding machine and the mold cavity to feed the foamed beads. An apparatus for feeding foamed beads characterized by interposing air injection means. 4. An air injection means comprising: a cylindrical body having an injection hole eccentrically formed on a side wall thereof and a housing surrounding the cylindrical body and forming a space for supplying air to the injection hole. The apparatus for sending foam beads according to claim 3, which is an injection part.