JPH051379Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an improvement of a raw material blowing device used for blowing foam beads into a foam mold.

(Prior Art) For example, when a foam model made of expanded styrene resin or the like is used as a vanishing model when casting differential gear cases, manifolds, etc., the foam model is manufactured using a foam mold. A conventionally known device used for blowing foamed beads as a raw material into the material is, for example, the device shown in longitudinal section in FIG.

Here, the foaming mold consists of a movable mold 1 and a fixed mold 2, and these molds 1 and 2 are pressed together by an air cylinder or the like (not shown) to define a cavity 3 between them.

In the raw material blowing device 4 here, a blowing pipe 7 to which a raw material transport pipe 6 is connected is fixed at right angles to a back plate 5 attached to a fixed mold 2, so that its tip surface is in the same plane as the inner surface of the fixed mold 2. At the same time, an air cylinder 8 is attached above this blowing pipe 7 whose upper end is closed, and an opening/closing member 9 is connected to this air cylinder 8, which is moved forward and backward in the blowing pipe in its axial direction. It is made up of. Here, the opening/closing member 9 is at its retracted limit position as shown in FIG.
It functions to open the tip opening 10 located at the tip of the inward flange 7a and is surrounded by the inward flange 7a, and conversely, at its advanced limit position, the tip can enter into the tip opening 10 as shown in FIG. 4b. and functions to close it.

In order to blow the raw material into the cavity 3 using such a device, after the molds 1 and 2 are closed as shown in the figure to partition the required cavity 3, the opening/closing member 9 is opened based on the operation of the air cylinder 8. The tip opening 10 is opened by the backward operation, and the raw material transport pipe 6 and the blowing pipe 7 are supplied from a raw material supply source (not shown).
into cavity 3 through foam beads 1, for example.
1 as shown in FIG. 4a.

After the cavity 3 is completely filled with the foam beads 11, the opening and closing member 9 is closed.
The tip opening 10 is closed by moving the nozzle 7 to the advanced position shown in FIG. 4b, and then the foamed beads 11 remaining in the blowing pipe 7 are sucked out through the raw material transport pipe 6. Thereafter, the foamed beads 11 in the cavity are heated to foam and fuse them, and are solidified in the foamed state, thereby forming a foamed product as a model.

However, according to such a conventional device, as is clear from FIG. 5, which shows a cross section of a foamed product,
There was a problem that the foaming raw material that entered between the inward flange 7a of the blowing pipe 7 and the opening/closing member 9 generated an annular burr as shown by number 12 in the figure, as well as thermal expansion of the opening/closing member 9. As a result, there was a problem in that depressions 13 were formed in the corresponding portions of the foamed product.

Therefore, in order to solve these problems, the sixth
A raw material blowing device as shown in the figure has been proposed.

This raw material blowing device 14 has components similar to those shown in FIG. By communicating with the cavity 3 through the passage 15, blowing of the raw material into the cavity is ensured.

In this device, foamed beads are blown into the cavity 3 and the passage 15 until they are completely filled, the tip opening 10 of the blowing tube 7 is closed by the opening/closing member 9, and then the foamed beads are By foaming, fusing, and cooling and solidifying, the burr 1 described in the conventional example
2. A foamed product without depressions 13 etc. can be obtained.

(Problems to be Solved by the Invention) However, in this conventional device, as shown in a plan view in FIG. 7a, on one side of the foamed product 16,
Gate portion 1 formed due to the presence of passage 15
7 is integrally molded, the gate portion 17
However, as shown in FIG. 7b, there is a problem in that it requires many man-hours to cut and remove at the required positions, and the foamed beads required to form the gate part 17 cause a decrease in the raw material yield. It was hot.

This invention was made by paying attention to such problems in the conventional technology, and it is possible to completely prevent the occurrence of burrs and dents in foamed products.
An object of the present invention is to provide a device for blowing raw materials into a foam mold, which can also prevent the formation of gate portions therein, and can always produce appropriate foam products.

(Means for solving the problem) The device for blowing raw materials into the foam mold of this invention is as follows:
It is attached to a foaming mold that fuses and fuses foamed beads to form a foaming mold, and in the attitude of entering the cavity, a raw material blowing device that controls the supply of foamed beads into the cavity is connected to a raw material transport pipe. a blowing tube; and a lid member that tightly contacts the tip surface of the blowing tube and closes the tip opening, while opening the tip opening, by displacement relative to the blowing tube in an axial direction or in a direction perpendicular to the axis. and the positions and dimensions of these blowing pipes and lid members are such that when the tip opening is closed, the inside of the cavity is a raw material blowing space;
It is designed so that it can be completely separated from the entry space of the raw material blowing device.

(Function) In this raw material blowing device, when the direction of relative displacement of the lid member with respect to the blowing tube is, for example, the axial direction of the blowing tube, the lid member is separated from the distal end surface of the blowing tube and the distal end of the blowing tube is moved. By supplying foamed beads to the cavity with the opening communicating with the cavity from between them, the required locations in the cavity can be completely filled with the foamed beads, and in this way After supplying the foamed beads, the lid member is brought into close contact with the lower end surface of the blowing tube to close the tip opening of the blowing tube based on the relative displacement between the lid member and the blowing tube. By completely separating the inside of the cavity into a raw material blowing space filled with foamed beads and an entry space of the raw material blowing device in which no foamed beads remain, by at least one side, burrs can be eliminated in the raw material blowing space. , it is possible to produce a foamed product as desired without any depressions or the like.

(Example) This invention will be explained below based on illustrated examples.

FIG. 1 is a longitudinal sectional view showing an embodiment of this invention, in which 21 indicates a movable type and 22 indicates a fixed type. Here, the movable mold 21 is pressed against the fixed mold 22 by an air cylinder or the like (not shown), and both molds 21 and 22 define a cavity 23 between them in the mold closed state.

In the raw material blowing device 24 shown in this example, the fixed mold 2
The air cylinder 27 is attached to the back plate 25 attached to the back plate 25 via the bracket 26, and the piston rod 27a of this air cylinder 27 is
By connecting the blowing pipe 28 that passes through both the back plate 25 and the fixed mold 22 at right angles, the blowing pipe 28 located in a portion corresponding to the center of the cavity 23 can be connected to the piston rod 2.
In the retracted position of the piston rod 7a, the tip of the piston rod 27a slightly enters the cavity 23, as shown in FIG. 1a, and in the extended position of the piston rod 27a, as shown in FIG. Operate to penetrate approximately half of the cavity depth. In addition, in this example, the blow pipe 2 is attached to the other end of the rod 29, which has one end fixed to the cylinder 27b of the air cylinder 27 and extends in the axial direction inside the blow pipe.
A lid member 30 having a contour dimension substantially equal to the outer peripheral dimension of the mold 8 is connected, and the lower end surface of the lid member 30 in the figure is connected to the inner surface of the movable mold 21 in the mold closed state as shown. , stick together with great force. Here, when the piston rod and eventually the blowing tube 28 are retracted, the lid member 30 allows the lower end opening 31 of the blowing tube 28 to communicate with the cavity 23 through the space between it and the blowing tube tip surface 28a, and also allows the blowing gap 2
8 when it advances, it closely contacts the tip end surface 28a to close the lower end opening 31 and functions to completely separate the inside of the cavity 23 into a raw material blowing space 23a and a raw material blowing device entry space 23b.

Further, numeral 32 in the figure indicates a raw material transport pipe that is connected to the blowing pipe 28 and transports foamed beads as a raw material from a raw material supply source (not shown).

The operation of the device configured in this way will be explained below.

Initially, the cavity 2 is closed by closing the movable mold 21 and the fixed mold 22 with a sufficiently large force.
3, and the lid member 30 is attached to the movable mold 21.
After that, attach the piston rod 27
By retracting a and the blowing pipe 28,
The tip opening 31 is communicated with the cavity 23, and the foamed beads 33 are supplied into the cavity from the raw material transport pipe 32 through the blowing pipe 28.

Such supply of the foamed beads 33 continues until the required locations within the cavity, in the illustrated example, the outer portions of the blow tube 28 and the lid member 30, are completely filled with the foamed beads 33, and the outer portions are filled. When the piston rod 27a and the blowing tube 28 are advanced as shown in FIG. is closed, and at the same time, the inside of the cavity is filled with a raw material injection space 23a filled with foamed beads,
It is completely separated into an entry space 23b of the raw material blowing device 24 occupied by the blowing pipe 28 and the lid member 30. Here, this entry space 23b becomes a smooth columnar space without unevenness by making the outer peripheral dimension of the blowing pipe 28 and the outline of the lid member 30 substantially equal. Further, here, this entry space 23b is formed by a lid member 30 extending over the entire circumference of the blowing pipe 28.
Since the space is partitioned by close contact between the two, the entry of raw materials into the entry space is completely prevented.

After that, the foamed beads 33 remaining in the blowing pipe are removed by suction through the raw material transport pipe 32, and then the foamed beads 33 in the cavity are sequentially foam-fused, cooled, and solidified to form a foamed product. .

The foamed product molded in this way becomes a foamed product 34 having a through hole 34a in the center, as shown in the plan view and cross-sectional view in FIG. Inconvenient burrs 12, depressions 13, etc. do not occur at all.

FIG. 3 is a sectional view showing another embodiment of this invention, and in this example, at the side end of the cavity 23,
Raw material blowing device 35 that is arranged to enter there
An air cylinder 27 is attached above the blowing pipe 28 directly fixed to the back plate 25,
A lid member 30 is connected to the tip of a rod 29 that is connected to the air cylinder 27 and moves forward and backward within the blowing pipe.
0, especially its thickness, and the blowing pipe 2.
8, the raw material injection space 23a can be sealed as shown in FIG. 3a.

In this example, the foamed beads 33 are supplied into the cavity 23, particularly into the raw material injection space 23a, by advancing the rod 29 using the air cylinder 27, so that the tip opening 31 of the blowing pipe 28 is inserted into the fixed type. The distal end surface 28a of the blowing tube 28, which is substantially aligned with the inner surface of the blowing tube 22, and the lid member 30 are communicated with the raw material blowing space 23a. 31 is closed by retracting the rod 29 to bring the lid member 30 into close contact with the distal end surface 28a of the blowing pipe 28 over its entire circumference, as shown in FIG. 3b. conduct. Here, when closing the tip opening 31, a taper surface provided on the outer circumferential portion of the blowing tube tip surface 28a,
The tapered surface provided on the peripheral portion of the lid member 30 is
It is preferable to make surface contact as shown in Figure c,
This ensures complete closure of the tip opening 31.

In addition, here, during the closing operation as described above, the lid member 30 has a circumferential surface with appropriately selected dimensions, and the material injection space 23a
The entrance opening from the entrance space 23b side is completely closed to separate the raw material injection space of the cavity 23 from the entrance space 32b of the raw material injection device 35.

Therefore, the foamed product produced according to this example also has a particularly low material suction space 23a.
is completely sealed by the circumferential surface of the lid member 30,
There is nothing in the raw material injection space that can cause burrs, dents, etc., so it is extremely smooth without any unevenness.

This invention has been explained above based on illustrated examples, but
In the case of a device that drives the lid member when opening and closing the tip opening of the blowing tube, the driving direction of the lid member may be perpendicular to the axis of the blowing tube, and the driving direction of the lid member or the blowing tube may be As the means, a gear mechanism or other known reciprocating drive means can also be used.

(Effects of the invention) Therefore, according to this invention, the tip opening of the blowing tube is brought into close contact with the tip end surface of the blowing tube based on the relative displacement with respect to the blowing tube, and is separated from the lid member. By closing and opening the cavity, and by completely separating the raw material blowing space and the raw material inlet space in the cavity with the tip opening closed, the raw material suction space and the partitioned portion of that space are completely separated. Since it is possible to remove any parts that cause burrs, dents, etc. in the foamed product, it is possible to always produce extremely smooth foamed products without unevenness, steps, etc. that are unnecessary for blowing.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of this invention, Fig. 2 is a view showing a foamed product produced by the device shown in Fig. 1, Fig. 3 is a sectional view showing another embodiment of this invention, and Fig. 4 is a sectional view showing an embodiment of this invention. , 6 are cross-sectional views showing conventional examples, respectively.
FIGS. 5 and 7 are views showing foamed products produced by conventional devices, respectively. 21... Movable type, 22... Fixed type, 23... Cavity, 23a... Raw material injection space, 23b
...Entry space, 24, 35...Raw material blowing device, 27...Air cylinder, 28...Blowing pipe, 2
8a... Tip surface, 29... Rod, 30... Lid member, 31... Tip opening, 32... Raw material transport pipe, 3
3... Foam beads.

Claims (1)

[Claims for Utility Model Registration] It is attached to the foam molds 21 and 22 for foaming and fusing foam beads to form a foam molded product, and in the attitude of entering the cavity 23, the foam beads are supplied into the cavity. In the raw material blowing device, the raw material blowing device is connected to the blowing pipe 28 to which the raw material transport pipe 32 is connected, and due to relative displacement with respect to this blowing pipe, the raw material blowing device is brought into close contact with the distal end surface 28a of the blowing pipe, and the distal end opening 31 of the blowing pipe is and a lid member 30 that closes the opening and opens the opening at the tip thereof, and when the opening at the tip is closed, the inside of the cavity is divided into the raw material blowing space 23a and the entrance space 2 of the raw material blowing device.
A device for blowing raw materials into a foam mold, which can be separated into 3b and 3b.