JPH043786Y2 - - Google Patents

Description

[Detailed description of the invention] <Technical field> This invention relates to a raw material filling device for foam molding, in which raw material particles made of expandable thermoplastic resin such as expanded polystyrene beads are filled into the cavities of a mold, and heated. It relates to a raw material filling device used in so-called bead molding, which produces molded products by foaming.

<Prior art> The general structure of the above-mentioned raw material filling device for foam molding includes a filling port that opens into the mold cavity of the mold, a raw material supply port that is connected to a supply hose for raw material particles, and a pressure source for filling. It has an air inlet, and by injecting pressurized air introduced from this inlet into the mold cavity from the filling port, the raw material particles are sucked from the supply port, that is, the supply hose, and the raw material particles are sucked into the mold cavity together with the pressurized air. The communication between the filling port, the supply port, and the inlet port is shut off or opened by a control rod that slides within the filling device to control the filling of raw material particles. ing. In addition,
The control rod is actuated by a cylinder mechanism such as an air cylinder.

After filling the mold cavity of the mold with the raw material, the filling port opening into the mold cavity is closed by the tip of the control rod, and the tip surface of the control rod becomes integrated with the inner surface of the mold. It is designed to form a part of the mold surface, and there are steps and unevenness between the tip surface of the control rod and the mold surface, and the filling port part forms a protruding burr on the molded product. This prevents the filling from forming or leaving dirty marks from the filling port.

However, in the case of a conventional raw material filling device, the control rod is formed with a circular cross section, and moves forward and backward while being supported by a circular sliding hole formed in the material filling device to perform the control function. It's becoming like that. Therefore, the control rod is used in a state in which it rotates freely inside the material filling device without being subject to any restrictions in the circumferential direction.

Therefore, if the surface of the mold where the filling port of the raw material filling device opens is a horizontal surface, if the tip of the control rod is also formed on a horizontal surface, there will be no problem even if the control rod rotates. When the filling port is closed with the distal end surface of the control rod, the distal end surface of the control rod always coincides with the mold surface.

However, depending on the shape of the molded product, that is, the shape of the cavity of the mold, the filling port of the raw material filling device may be opened on an inclined surface or a curved surface of the mold surface. It may be necessary to install it. In this case, the tip end surface of the control rod is also formed into an inclined or curved surface that matches the inclination or curvature of the mold surface. However, as mentioned above, if the control rod rotates freely, the inclination and curving direction of the tip surface of the control rod will not match the inclination and curving direction of the mold surface, and the formed foamed product will be damaged. There was a problem in that steps and unevenness were formed on the surface at the filling opening, which impaired the appearance of the molded product and reduced its commercial value.

In order to solve the above problem, it was considered to extend the rear end of the control rod to the outside of the material filling machine and provide an appropriate rotation prevention mechanism on the extended part of the control rod, but the structure of the control rod was complicated. become,
An airtight mechanism between the control rod and the material filling device is also required, which increases the cost of the equipment and increases the number of causes for the control rod to malfunction. There were problems with storage, etc., and it was not practical.

<Purpose> Therefore, the purpose of this invention is to solve the above-mentioned problems of the prior art, to provide a control rod that can reliably prevent rotation, has a simple structure, and is reliable in operation.

<Configuration> And, as a configuration for achieving the above object, when heating and foaming raw material particles made of expandable thermoplastic resin in the mold cavity of a molding die to form a molded product of a predetermined shape, the above-mentioned configuration is adopted. In a raw material filling device for foam molding for force-feeding and filling raw material particles into the cavity of the mold by jetting pressurized air, the control rod is slidably supported by a control rod for controlling filling. The sliding hole of the raw material filling device is characterized in that at least the sliding portions thereof are formed into a non-circular shape.

<Example> Next, an example of this invention will be described below with reference to the drawings.

FIG. 1 shows a state in which the raw material filling device is attached to a mold, and 1 is the filling device main body, and the tip is attached to the inner surface of the mold 21 constituting the mold cavity 20 of the mold 2, i.e. A filling port 10 is formed that opens on the mold surface, and at the rear thereof, a supply port 11 for raw material particles connected to a supply hose 3 for raw material particles and an inlet port 12 for pressurized air connected to a pressure air pipe 4 are formed. The filling port 10, the supply port 11, and the introduction port 12 communicate with each other through a cavity 13 formed inside the filling device body 1.

Reference numeral 5 denotes a control rod, which is provided so as to be able to move forward and backward in the cavity 13 of the filling device main body 1. At the tip of the control rod 5, there is a plug body part that can be fitted into the filling port 10 to seal it. 50 is formed, and the tip end face of this plug body part 50 is not horizontal, but is formed in a shape that matches the inclination, curvature, etc. of the inner surface of the mold 21, that is, the mold surface.

An elongated rod-shaped operating shaft 51 is formed at the rear of the control rod 5, and the operating shaft 51 and the front stopper portion 50 are fixedly attached so as not to rotate with respect to each other. The operating shaft 51 is inserted through the inside of the cylinder section 6 which is connected and attached to the rear part of the filling device main body 1 . By moving the piston section 52 provided at the rear end of the operating shaft 51 forward and backward using the operating air introduced into the cylinder section 6, the entire control rod 5 is operated back and forth. There is.

Furthermore, the operating shaft 51 of the control rod 5 is not a simple circular shape, but is formed into a bar shape with a hexagonal cross section in the case of the figure.
A sliding hole 60 formed in the front surface through which the slider 1 is inserted is also formed to have a hexagonal cross section corresponding to the operating shaft 51. Therefore, the control rod 5 cannot rotate in the circumferential direction of the control rod 5 and can only slide in the axial direction due to the engagement between the hexagonal operating shaft 51 with a non-circular cross section and the sliding hole 60. I will do it.

The raw material filling device having the above-mentioned structure is used in exactly the same way as a conventional conventional raw material filling device, and as shown in FIG. is disposed at the rear of the cavity 13 of the filling device main body 1, the pressurized air introduced into the pressure air introduction port 12 is injected into the mold cavity 20 of the mold 2 from the filling port 10. As a result, raw material particles are sucked from the raw material particle supply port 11 and are force-fed and filled into the mold cavity 20 together with pressurized air.

Then, as shown in FIG. 2, when the mold cavity 20 is completely filled with the raw material particles B, the control rod 5 is advanced to close the filling port 10 with the stopper portion 50.
Shut off pressurized air and pressure filling of raw material particles.

At this time, the tip end surface of the plug body part 50 is arranged in a completely integrated state, smoothly continuing along the inclination and curvature of the inner surface of the mold 21 of the mold 2, and
There is no difference in level or unevenness between the tip surface of the mold 21 and the surrounding inner surface of the mold 21.

In the raw material filling device described above, the structure of the filling device main body 1, that is, the filling port 10, the supply port 11, the introduction port 12, etc., is exactly the same as that of a normal material filling device for foam molding. The structure shown in the figure can be modified as appropriate. Further, as the cylinder portion 6, a normal air cylinder or other various cylinder mechanisms can be adopted.

As for the cross-sectional shapes of the operating shaft 51 of the control rod 5 and the sliding hole 60 of the cylinder portion 6, the hexagonal cross-sectional shape shown in the figure is relatively easy to manufacture and has good strength and reliability of operation. Although this is preferred, any non-circular shape other than a perfect circle, such as a quadrilateral, other polygons, ellipses, ellipses, etc., can also be used. Further, it is also possible to use a shape in which a part of a circle is cut out, a shape in which a part of the circle has protrusions or irregularities, or a gear or spline shape in which the entire outer periphery of the circle has irregularities.

In addition, in practice, the control rod 5 does not need to have a non-circular cross section over its entire length.
Like the illustrated actuating shaft 51, only the portion that slides through the cylinder portion 6 may be formed to have a non-circular cross section.

Next, the tip end surface of the stopper portion 50 of the control rod 5 is formed into an arbitrary inclined surface, curved surface, etc. along the inner surface shape of the mold 21 of the mold 2.
In addition, grooves, protrusions, and other uneven shapes may be formed as appropriate in accordance with the shape of the molded product to be molded, that is, the inner surface shape of the mold 21.

<Effects> According to the raw material filling device of this invention configured as described above, the control rod 5 that closes the filling port 10
Since the slide hole 60 of the cylinder part 6 that slides and supports the control rod 5 is formed to have a non-circular cross section, the control rod 5 is is no longer able to rotate in the circumferential direction, and the control rod 5 moves only in the axial direction.

Therefore, if the tip end surface of the control rod 5 is formed in advance into a shape that corresponds to the inner surface of the mold 21 of the mold 2, that is, the inclination and curvature of the mold surface, when the control rod 5 closes the filling port 10, In addition, the tip surface of the control rod 5 and the inclination or curved shape of the surrounding inner surface of the mold 21 always match reliably, making it possible to form a completely integrated and continuous mold surface, and the surface of the molded product is smooth. Therefore, there are no unevenness or steps in the filling port 10,
It is possible to produce foam molded products of high quality and high commercial value.

Moreover, in the case of this invention, there is no need to extend the control rod 5 to the outside of the filling device or add any additional structure to the filling device to prevent rotation, so the control rod 5 and the sliding hole 60 are omitted. The structure of the entire raw material filling device is completely the same as that of a normal raw material filling device without a rotation stopper. Therefore, the manufacturing cost of the entire raw material filling device is extremely low, and the bulk of the entire device is also low and can be made compact.

In addition, regarding the functionality of the filling device, there is no effect on the operation of the control rod 5 or the filling control effect of raw material particles, and it can be used just like a normal material filling device, making it extremely easy to use and practical. It is of high value.

[Brief explanation of the drawing]

The figure shows an example of this invention.
The figure is a sectional view, FIG. 2 is a cross-sectional view of the sliding hole portion, and FIG. 3 is a sectional view of the device in use. DESCRIPTION OF SYMBOLS 1... Filler main body, 10... Filling port, 2... Molding mold, 20... Mold cavity, 5... Control rod, 50...
... Plug body part, 51 ... Operating shaft, 6 ... Cylinder part,
60...Sliding hole.

Claims (1)

[Scope of utility model registration request] When raw material particles made of expandable thermoplastic resin are heated and foamed in the mold cavity of a mold to form a molded product of a predetermined shape, the raw material particles are heated and foamed into the mold by a jet of pressurized air. In a raw material filling device for foam molding for pressure-filling into a mold cavity, a control rod for controlling filling and a sliding hole of a raw material filling device that slidingly supports this control rod are arranged so that at least the sliding portion of each other is A raw material filling device for foam molding, characterized in that the shape is formed into a non-circular shape that cannot be rotated in the circumferential direction.