JPH0442336B2 - - Google Patents

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a plunger for mold blow molding that can be used in the mold blow molding of glass or plastic products to stably produce good products; The present invention relates to a molding method using.

(Prior art) Conventionally, as a type of manufacturing method for glass or plastic products such as bottles and pots, air is blown into the inside of a molten glass or plastic block while it is housed in a predetermined mold. A so-called die blow molding method is known in which a product having an outer shape corresponding to the molding cavity of the mold is produced by this method.

By the way, when performing mold blow molding like this,
Before the final forming by blowing air as described above, the molten glass or plastic mass is
It is necessary to drill air holes for blowing air, and for this purpose, for example, when manufacturing glass products, as is well known, the final forming process is performed by blowing air into the finishing mold. Prior to the operation, a molten glass gob (gob) cut to a predetermined size is usually housed in a predetermined rough mold, and a press operation is performed in which a tapered plunger is inserted into the gob. By applying this, a molten glass gob (parison) with air blowing holes is formed.

However, when forming a parison using such a plunger, the outer surface of the plunger comes into direct contact with the high temperature (usually about 1100 to 1200°C) gob, so continuous forming operations are required. In such cases, the overheating deteriorates the mold releasability from the gob and causes the gob to seize, resulting in defects such as cracks on the inner surface of the product and mechanical troubles. It had a problem that could easily occur.

Therefore, conventionally, such a plunger itself is formed to have a hollow shape, and a cooling tube (inner tube) is arranged in the inner hole of the plunger, so that the cooling fluid is ejected through the ejection hole provided in the cooling tube. This was designed to cool the inner surface of the plunger's inner hole.

(Problems) However, with such conventional methods, it was not possible to obtain a sufficient cooling effect, and it was not possible to provide an effective solution to the above-mentioned problems.

In other words, since the ejection holes provided in such cooling tubes are drilled by machining, it is difficult to form them, making the device expensive, and providing a large number of them reduces the mechanical strength of the member. Therefore, it has been extremely difficult to set a sufficient amount of cooling in such a cooling mechanism.

(Solution Means) Here, the present invention has been made against the background of the above-mentioned circumstances, and its purpose is to improve the quality of glass or plastic products by using them in mold blowing molding. An object of the present invention is to provide a plunger for die blow molding that can stably manufacture products, and a molding method using the plunger.

In order to achieve such an object, the present invention is characterized in that, when molding glass or plastic products, the molten glass or plastic mass is infiltrated into a predetermined mold. As a result, in the mold-cutting plunger for punching air blowing holes in the molten glass or plastic lump, the skeleton itself forming a continuous skeletal structure is made hollow, and holes are formed within the skeleton. A porous member is created in which a predetermined matrix material is inserted into the gaps between the skeletons of a ceramic structure to form an integral structure, allowing fluid to pass through the pores formed within the skeleton. using the porous member to form at least a part of the surface portion of the plunger that is penetrated into the molten glass or plastic mass, and opening the pores of the porous member on the surface thereof. This allows pressurized fluid supplied from the outside to be ejected onto the surface through the holes.

In addition, in the present invention, when molding a glass or plastic product, the molten glass or plastic product can be molded by inserting a plunger for molding into the molten glass or plastic lump housed in a predetermined mold. When drilling holes for air blowing into a plastic block, the skeleton itself that forms a continuous skeletal tissue is made hollow, and holes are formed in the gaps between the skeletons in the ceramic structure. A porous member is used in which a predetermined matrix material is inserted to form an integral structure so that fluid can pass through the pores formed in the skeleton. At least a portion of the surface of the porous member is infiltrated into the glass or plastic mass, and the pores of the porous member are opened at the surface so that a pressurized fluid supplied from the outside can pass through the pores to the surface. A state in which a predetermined pressure fluid is supplied to the mold blow molding plunger using a mold blow molding plunger that can be spouted upward, and the pressure fluid is jetted onto the surface of the mold blow molding plunger. The following also describes a method for forming glass or plastic products in which a plunger for mold blowing is inserted into a molten glass or plastic mass.
This is its characteristic.

(Example) Hereinafter, in order to clarify the present invention more specifically, an example of the present invention will be described in detail with reference to the drawings.

First, FIG. 1 shows an embodiment of a plunger for mold blowing used in mold blow molding of glass products having a structure according to the present invention.
As shown in this figure, the plunger 10 has a tapered shape with a circular cross section over its entire length, and is hollow inside, with an inner hole opening at the end surface on the base side. 12
is formed.

In the plunger 10 of this embodiment, the tip end portion 24, which is inserted into the molten glass gob during the molding operation, is constituted by the porous member 14.

That is, the porous member 14 is, for example,
After foaming a resin such as ester-based urethane, the film-like substance (foamed film) remaining around the skeleton is removed using compressed air, etc.
It is obtained by adhering a ceramic material such as ceramic slurry to the surface of the skeleton of a synthetic resin foam having a three-dimensional network structure, and then drying and firing it, as shown in Figure 2. A known ceramic structure 20 is used, in which the skeleton 16 itself forming a continuous skeletal structure as a whole is neutralized to form continuous pores 18 in the skeleton 16. is placed in a predetermined casting cavity, a predetermined molten metal is introduced into the casting cavity, and the molten metal is introduced into the skeletal gap.
A predetermined cast metal 22 as shown in FIG.
A porous member 14 having a structure in which the ceramic structure 20 is integrally embedded is preferably used.

Note that as the ceramic material forming the ceramic structure 20, cordierite, alumina, SiC, mullite, zirconia, etc. are appropriately selected and employed depending on the characteristics required for the intended plunger 10. ,Also,
The molten metal that forms the cast metal 22 has a chemical composition that is controlled according to the physical properties required for the plunger 10, and is preferably made of, for example, aluminum alloy, cast iron, cast steel, or copper alloy. It will be used.

That is, in the case of such a porous member 14, the cast metal 2 is placed in the cells constituted by the skeleton 16 that forms the porous structure of the ceramic structure 20.
2 is inserted into the ceramic structure 20 so that the cast metal 22 forms a matrix with the ceramic structure 20 to form an integral structure, while the pores 1 of the skeleton 16 in the cast ceramic structure 20
Intrusion of the molten metal into the hole 8 is prevented because the opening of the hole 18 is closed, and the hole 18 is maintained in a communicating state.

In addition, in the case of such a plunger 10,
The tip side portion 24 made of the porous member 14 is formed separately from the base side portion 26 made of a suitable metal material such as stainless steel, and then they are welded or the like. Although it is possible to form the ceramic structure 20 by integrating the ceramic structure 20 with the above-mentioned specific structure, it is particularly preferable to form the ceramic structure 20 with a shape corresponding to the distal end portion 24 of the target plunger 10. With the ceramic structure 20 placed in a casting cavity of a mold forming the plunger 10, the plunger 1
The ceramic structure 20 is integrally buried inside the ceramic structure 20 at the same time as the casting, so that the tip of the ceramic structure 20 is formed by performing a casting operation of 0. A cast product whose side portion is composed of the porous member 14 is thus formed.

Then, in the cast product thus formed, a grinding process or the like is performed on the outer circumferential surface of the distal end portion 24 made of the porous member 14 and the inner circumferential surface of the inner hole 12. Therefore, the holes 18 formed in the porous member 14 are opened on the outer circumferential surface and the inner circumferential surface thereof, thereby forming the intended plunger 10.

That is, in the case of such a plunger 10, the tip side portion 2 formed of the porous member 14
4, the porous member 14 has a structure in which the pores 18 form fine ejection holes that communicate with each other in a three-dimensional network, allowing the space within the inner hole 12 to communicate with the external space. -ing

By the way, in the case of the plunger 10 having such a structure, when performing the forming operation of the molten glass gob, although not shown, the opening of the inner hole 12 formed in the base side portion 26 is On the other hand, a supply passage for guiding a predetermined pressure fluid such as water or air is connected, and the predetermined pressure fluid is supplied into the inner hole 12 through the supply passage.

That is, in the plunger 10, the pressure fluid thus supplied into the inner hole 12 is ejected onto the outer surface through the ejection hole formed inside the plunger 10. By infiltrating the plunger 10 into the gob housed in a predetermined mold, as described above, under a condition in which a predetermined pressure fluid is ejected onto the outer surface, A molding operation is performed in which air blowing holes are bored in the gob to form a parison.

Here, in the plunger 10 having the above-described structure, the ejection hole is constituted by the hole 18 formed in the skeleton 16 of the ceramic structure 20 having the above-described specific structure. Because of the fact that it is possible to easily set such ejection holes with a substantially uniform distribution density over the entire surface of the outer surface that is infiltrated into the gob, the diameter of the ejection holes can be set to be extremely fine (for example, 0.05~
0.3 mm ² ), whereby an effective cooling effect can be exerted by the fluid flowing through its interior, and by the fluid ejected onto such outer surface. A highly rigid fluid film can be formed uniformly over the entire surface.

As described above, the pressure fluid supplied through the supply channel connected to the base side portion 26 of the plunger 10, that is, the pressure fluid jetted onto the outer surface of the plunger 10, may include water and air as described above. , lubricating oil, water vapor, etc. can be used singly or as a mixture thereof, and they can be selected as appropriate, but in particular, a mixture of water and air can be used as such pressure fluid. By using this, the water jetted onto the outer surface is vaporized by the heat of the gob, which can provide an even better cooling effect and create a more rigid fluid film (water vapor). A film) can be formed.

Therefore, by using such a plunger 10, a uniform and good cooling effect can be exerted throughout the entire mold during mold blow molding, and
Direct contact of the plunger 10 with the gob or parison can be avoided by the fluid film formed on its surface, and good mold release properties can be exhibited, thereby making it possible to prevent the plunger 10 from coming into direct contact with the gob or parison. In other words, welding of the parison to the plunger 10 can be effectively prevented, and defects in products and mechanical troubles can be effectively avoided.

Furthermore, since the plunger 10 does not come into direct contact with the gob or parison, it is possible to effectively prevent scratches and smoothen the surface of the parison formed. This also has the effect that the strength (especially impact strength) of the product can be effectively improved.

Furthermore, since it is not necessary to apply lubricating oil or the like to the outer surface of the plunger 10, the safety and labor of the molding operation can be advantageously reduced, and the molding cycle can also be improved. This can be achieved effectively.

Further, in the case of such a plunger 10, there is no need to provide a cooling tube as in the conventional case, and the ejection holes in such a plunger 10 are not formed by post-processing, but are extremely easy to manufacture. In addition, the structure of the device can be effectively simplified, and a plunger having excellent effects as described above can be manufactured easily and at low cost.

Incidentally, using the plunger 10 having the structure according to this embodiment, air is used as the pressure fluid at a pressure of 1.0 to 1.2
Pressurized to Kg/cm ² (gauge pressure), or
Using a mixture of air pressurized to 0.2 to 0.5 Kg/cm ² (gauge pressure) and water pressurized to 1.0 to 1.2 Kg/cm ² (gauge pressure), the supply channels are When the gob is molded while being supplied into the inner hole 12 through the plunger, the air or water is ejected from the outer surface of the plunger 10, and the water is vaporized by the heat of the gob. by forming a water vapor film,
A fluid film was formed there, and good molding could be carried out stably.In particular, the strength of the product formed from the parison obtained in this way was compared to conventional products. It has been confirmed that the improvement was achieved by 30 to 50%.

The embodiments of the blow molding plunger having the structure according to the present invention and the molding method using the same have been described in detail above, but these are literal examples, and the present invention is limited only to such specific examples. It is not intended to be interpreted as such.

For example, in the plunger 10 in the above embodiment, the distal end portion 24 that is inserted into the gob is entirely made of the polyphilic member 14, but only a portion thereof is made of the porous member. It may be configured as follows.

Further, in the plunger 10 in the above embodiment, the inner hole 12 is provided inside the plunger 10, and the thickness of the wall portion is made substantially uniform throughout, so that the pressure fluid to be ejected is Although jet rolling has attempted to make the jetting amount uniform, especially in the porous member 14 as illustrated, the pores 18 formed inside the member are three-dimensionally continuous. Therefore, it is also possible to form it in a solid shape and provide a fluid supply hole communicating with the cavity 18 formed inside on the base side thereof.

Furthermore, the ceramic structure 20 used in the present invention is not limited to one having a three-dimensional network structure as illustrated, but also includes
It is also possible to use those having other skeleton structures such as a crest shape or a comb shape.

In addition, in the above embodiment, for the plunger used when forming the molten glass gob,
Although an example in which the present invention is applied has been shown, the present invention can be similarly applied to a plunger used in molding a molten plastic lump, thereby achieving the same effects as the above embodiment. Of course, it can also be effectively performed.

In addition, although not listed one by one, the present invention can be implemented in embodiments with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art.
It goes without saying that all such embodiments are included within the scope of the present invention as long as they do not depart from the spirit of the present invention.

(Effects of the Invention) As is clear from the above description, in the plunger for mold blow molding according to the present invention, a large number of holes serving as fluid flow paths can be easily set inside the plunger. Therefore, by supplying a cooling fluid into the holes, an excellent cooling effect can be exhibited, and since the holes can be formed with an extremely fine diameter, the cooling fluid can be ejected through the holes. The fluid film is created by the pressure fluid
It can be formed with high rigidity on the surface of the plunger.

Therefore, by using such a plunger for mold blowing, the fluid film formed on the surface of the plunger can be prevented from coming into direct contact with the molten glass or plastic mass during mold blowing. Therefore, it is possible to avoid the occurrence of defects and mechanical troubles in the product, and to achieve good mold releasability. It can be manufactured.

Furthermore, in the plunger for mold blowing according to the present invention, since the pressure fluid ejection hole is constituted by a hole formed in the skeleton of the ceramic structure, the above-mentioned Therefore, a plunger with excellent effects can be manufactured easily and at low cost.

[Brief explanation of drawings]

FIG. 1 is an explanatory longitudinal cross-sectional view showing one embodiment of a plunger having a structure according to the present invention, and FIG. 2 is a cross-sectional view showing an enlarged main part of a ceramic structure suitably used in manufacturing such a plunger. FIG. 3 is an explanatory cross-sectional view showing an enlarged main part of a porous member formed using such a ceramic structure. 10: Plunger, 12: Inner hole, 14: Porous member, 16: Skeleton, 18: Hole, 20: Ceramic structure, 22: Cast metal.

Claims (1)

[Scope of Claims] 1. During mold blow molding of glass or plastic products, air is introduced into the molten glass or plastic mass housed in a predetermined mold by infiltrating the molten glass or plastic mass into the molten glass or plastic mass. In a mold-cutting plunger for drilling a blowing hole, the skeleton itself forming a continuous skeletal tissue is hollow, and a predetermined hole is inserted into the gap between the skeletons in a ceramic structure in which holes are formed within the skeleton. A porous member is used to form an integral structure by incorporating a matrix material of By forming at least a portion of the surface portion of the plunger that is penetrated into the molten glass or plastic mass, and by opening the pores of the porous member at the surface thereof, the pressure fluid supplied from the outside can be transferred to the pores. A plunger for mold blowing, characterized in that it is capable of ejecting water onto a surface through a hole. 2. In mold blow molding of glass or plastic products, a plunger for mold blow molding is inserted into the molten glass or plastic mass housed in a predetermined mold to blow air into the molten glass or plastic mass. When drilling holes, the skeleton itself that forms the continuous skeletal tissue is made hollow, and a predetermined matrix material is inserted into the gaps between the skeletons in the ceramic structure in which holes are formed within the skeleton. Using a porous member that has an integral structure that allows fluid to pass through the pores formed in the skeleton,
By making the porous member constitute at least a part of the surface area that is penetrated into the molten glass or plastic mass, and by opening the pores of the porous member at the surface thereof,
By supplying a predetermined pressure liquid to the blow molding plunger using a mold blow molding plunger capable of spouting a pressure fluid supplied from the outside onto the surface through the hole, A method for molding a glass or plastic product, characterized in that the plunger for mold blowing is inserted into the molten glass or plastic mass under a condition in which the pressure fluid is jetted onto the surface of the product.