JPH0794327B2 - Method for manufacturing glass bottle with high impact strength - Google Patents

Description

Description: [Industrial application] The present invention relates to a method for producing a glass bottle, which is designed to increase the impact strength of the glass bottle.

[Prior Art] In the conventional glass bottle manufacturing by an IS machine (individual sectional machine), in order to improve the mold release from the glass, it is regularly performed (every 20 minutes to 1 hour).
Apply oil for lubrication to rough molds, mouth molds, baffles, etc. by hand. As a plunger for molding a parison, a plunger coated with a self-fluxing alloy mainly containing Ni is usually used for molding.

However, when the oil is applied, the graphite in the oil application component adheres to the plunger. The adhered graphite is transferred to the parison side when pressed by the plunger, causing foaming and scratches on the inner surface of the glass bottle.

In addition, even if the plunger is coated with a wear-resistant Ni-based self-fluxing alloy, some peeling due to oxidation and wear of the plunger itself is unavoidable, and this peeled material still adheres to the inner surface of the parison as a metallic foreign substance. Decrease the impact strength of.

Further, it is conceivable that the sliding powder generated in the sliding portion of the positioner that guides the lifting and lowering of the plunger adheres to the plunger and moves to the inner surface of the parison to reduce the impact strength of the bottle.

That is, the impact strength of the glass bottle is greatly affected by scratches on the inner surface of the glass bottle, and foaming due to oiling, adhesion of foreign matter from the plunger, and adhesion of sliding powder on the positioner part to the parison cause damage to the inner surface of the glass bottle. There are three major causes.

[Problems to be Solved by the Invention] In order to increase the impact strength of a glass bottle, instead of the crude oil coating, the Alblack IS method (a gaseous hydrocarbon is flame-injected into a rough die to form a carbon coating on the rough die surface) It is conceivable to use a forming method, a patent application publication, Sho 63-502891) or change the coating material of the plunger to ceramic (Japanese Patent Laid-Open No. 1-239029). Only about half the effect can be obtained, and the strength varies widely. Further, when a plunger having a ceramic coating on the entire surface is used, a new problem may occur such that the mouth of the bottle is scratched and the product becomes defective in appearance.

An object of the present invention is to significantly increase the impact strength of a glass bottle and stabilize it (reduce the strength variation).

[Means for Solving the Problems] The method for producing a glass bottle according to the present invention for achieving the above object comprises the following method. (1) A sliding surface between a bushing and a spring guide of a positioner that guides the up and down movement of a plunger by using a metal plunger having a thermal spray coating of a Co-based self-fluxing alloy on at least the part that comes into contact with the parison during molding of the parison. A wear-resistant coating is formed on the surface of the rough die and mouth die using a positioner that prevents the generation of sliding powder on the bushings and spring guides by using this wear-resistant coating. A parison is formed by periodically injecting 0.75 or more gaseous hydrocarbons or a mixture of two or more gaseous hydrocarbons with a flame to form a carbon film for lubrication. The method for producing a glass bottle having high impact strength is characterized in that it is blow-molded by.

(2) A metal plunger with a mouth-forming part of the plunger body for forming a parison coated with a self-fluxing alloy of Hv800 or less, and the tip of which is ceramic-coated by a chemical vapor deposition method or a physical vapor deposition method,
Using a positioner that forms a wear resistant coating on the sliding surface of the bushing and spring guide of the positioner that guides the lifting and lowering of the plunger, and prevents the generation of sliding powder on the bushing and spring guide by this wear resistant coating, A state in which a carbon film for lubrication is formed by periodically flame-injecting a gaseous hydrocarbon having a C / H ratio of 0.75 or more or a mixture of two or more gaseous hydrocarbons on the surface of the rough mold and the mouth mold. The method for producing a glass bottle having a high impact strength is characterized in that the parison is formed by, and the obtained parison is blow-molded by an ordinary method.

[Operation] In the invention (1) of the present invention, instead of coating, formation of a carbon film by flame injection of a gaseous hydrocarbon or a mixture of two or more kinds is applied. Both the formation of this carbon coating and the formation of the thermal spray coating of the Co-based self-fluxing alloy on the metal plunger are applied.

By forming a thermal spray coating of Co-based self-fluxing alloy on the metal plunger, metal foreign matter can be transferred to the inner surface of the parison due to oxidation of the metal plunger itself and its peeling.
It is more completely prevented compared to the thermal spray coating of Ni-based self-fluxing alloy. Also, compared to ceramic coating, Co
The self-fluxing alloy does not scratch the mouth of the bottle. Further, foaming due to oil application is also prevented by using a carbon film formation by spraying a gaseous hydrocarbon flame instead of oil application. Further, since the abrasion resistant coating is formed on the sliding surface of the bushing and the spring guide, which is the sliding portion of the positioner, generation of sliding powder is suppressed. Therefore, it is possible to eliminate the three major causes of impact strength deterioration.

According to the present invention, the impact strength of a glass bottle is increased by a single method such as an impact strength increase only by thermal spray coating of a Co-based self-fluxing alloy, an impact strength increase only by forming a carbon film by flame injection of gaseous hydrocarbons, etc. It is larger and stable with less variation. Moreover, since the lower limit of the variation range shifts significantly to the higher strength side than the lower limit of the strength variation range in the case of the above single method, the variation in reduction and strength safety are synergistic with respect to the sum in the case of the above single method. It can be said that it has an effect.

In the invention of (2) above, in addition to the action of the invention of (1),
Even if a ceramic coating is applied to a part of the surface of the plunger, it is possible to obtain the effect of suppressing scratches on the mouth of the bottle.

[Examples] Preferred examples of the method for producing a glass bottle having a high impact strength according to the present invention will be described below with reference to the drawings.

First Embodiment FIGS. 1 to 4 show a first embodiment of the present invention. FIG. 1 shows one section of an IS glass molding machine, where 1 is a plunger that pushes the glass soul (gob) from the inside to form the inner shape of the parison, 10 is a mouth mold, and 11 is a guide ring. Rough mold 12 open, i.e. baffle
With 13 (see FIG. 2) removed, a gaseous hydrocarbon is flame-injected from a nozzle 14 located above the rough mold 12,
On each surface of the rough mold 12, the mouth mold 10, and the guide ring 11,
A carbon film for lubrication (release) is formed. Nozzle 14
Is supplied with a gaseous hydrocarbon or a mixture thereof with a C / H ratio of 0.75 or more, and oxygen and LPG are combusted to constantly create a high temperature atmosphere (separator), and the Hydrocarbon gas such as acetylene is injected into the atmosphere to cause thermal decomposition instantaneously to form a carbon coating on each mold such as a rough mold.

On the other hand, on the surface of the plunger body made of alloy tool steel,
As shown in FIG. 4, a spray coating 2 of a self-fluxing alloy of cobalt type (for example, Co type Cr ₃ C ₂ or the like) is formed on the entire surface of the portion contacting the gob in advance.

Generally, when a plunger with Ni self-fluxing alloy coated on the entire glass contact area is used, a small amount of metal oxide is produced by contact with high temperature glass, which peels off and adheres to the parison and blows the parison. Also remains attached to the inner surface of the bottle. Then, due to the difference in the expansion coefficient between the glass and the metal oxide at the stage of cooling after molding, the tensile force acting on the glass to which the metal oxide is attached causes the crack to grow from the metal oxide as a starting point.

FIG. 3 shows a part of the positioner of the first embodiment of the present invention. A wear resistant coating 30 is formed on the sliding surface of the positioner 20 between the bushing 24 and the spring guide 25 (a guide that guides the spring 26), so that the worn metal powder in the sliding portion can be removed from the air curtain air. It prevents the glass bottle from being mixed with the glass and adhering to the plunger 1 to lower the strength of the glass bottle.

More specifically, the wear resistant coating 30 is made of TiN, TiC, SiC, A
It consists of ceramics such as l ₂ O ₃ . These wear resistant coatings
30 has a hardness of Hv1000 or more at room temperature. Although the components of the positioner 20 are made of iron-based metal, the wear-resistant coating 30 significantly enhances the wear resistance of the surface. As a result,
Abrasion resistant coating even if glass powder (Hv500) or iron powder (Hv200 to 800) existing inside the positioner enters the sliding surface
Since 30 has a higher hardness, the sliding surface is not scraped off, and the occurrence of scratches and wear that cause the generation of metal powder is prevented. Further, these ceramic wear resistant coatings 30 also prevent adhesive wear caused by contact between metals.

It is desirable to form the same wear resistant coatings 31, 32 on the sliding surface between the outer periphery of the split ring 19 and the bushing 24 and the sliding surface between the washer 29 and the bushing 24.

FIG. 2 shows that the plunger 1 coated with the thermal spray coating of the Co-based self-fluxing alloy as described above is used to periodically inject flames of gaseous hydrocarbon or a mixture thereof onto the surfaces of the rough mold and the mouth mold to form carbon. With the film formed, the parison
It shows a state where 15 is formed. The parison 15 thus obtained is blow molded by a conventional method to obtain a glass bottle product.

In this glass bottle manufacturing method, a spray coating of a Co-based self-fluxing alloy is formed on the surface of the plunger 1, a carbon film is formed on the surface of the plunger body by flame injection, and wear resistance of the sliding portion of the positioner portion is provided. The formation of the protective coating 30 is used together.

Since the plunger 1 has the Co-based self-fluxing alloy coating 2, surface oxidization of the plunger main body and peeling due to wear are suppressed, and thus these peeled substances are transferred to the inner surface of the parison to reduce the impact strength of the glass bottle. To prevent. Further, since the carbon film is formed by flame injection of gaseous hydrocarbon instead of oiling, it is possible to prevent the impact strength of the glass bottle from being lowered due to foaming during parison formation accompanying oiling. Further, it is possible to prevent the generation of sliding powder at the sliding portion of the positioner 20 and prevent it from adhering to the plunger. Therefore, it is possible to remove the three causes of the impact strength reduction of the glass bottle at the same time.

When tested using a vial bottle with a volume of 200 cc and a thickness of 2.2 mm, the following impact strengths were measured for carbon film formation only, plunger coating only, carbine film formation and plunger coating, respectively. .

As you can see from the above table, by performing both at the same time,
The average strength is doubled and the variation is small,
It can be seen that the lower limit of variation is significantly improved. FIG. 5 shows the relationship between the impact strength and the cumulative damage rate in the case of the conventional molding method A, carbon film formation only B, plunger coating only C, and both simultaneous D. As shown in D, it can be seen that the variation is small and the lower limit of the variation is significantly improved. These are two effects of the first embodiment D.
Sum of effects in the case of two single cases (B, C) (The sum of effects in the case of a single case is the larger variation in the case of variation B or C, and the smaller the lower limit of variation in the case of B or C. It is considered to be more than the lower limit of variation).

In addition, in order to confirm the effect of suppressing the generation of sliding powder by the positioner, the above positioner was attached to a section of the IS section glass molding machine of 8 sections that press-blown 180cc juice bottles, and molding was performed in this section. The metal powder generation rate between the glass bottle and the glass bottle molded in other sections was investigated.

As a result, the glass powder molded in the section equipped with the conventional positioner has an average metal powder generation rate of 4.7% in 72 hours.
However, the half-monthly average for glass bottles molded in the section with the positioner dropped to 0.09%. Further, the positioner was continuously operated without lubrication, but the metal powder generation rate did not increase even after about one month.

Second Embodiment The second embodiment is the same as the first embodiment except that the oxidation resistant coating of the plunger 1 is changed. FIG. 6 shows the plunger 1 used in the second embodiment. The plunger 1 consists of a self-fluxing alloy 2 (Ni-based Co
System), the tip of which is coated with at least one ceramic coating 3 of any one of TiN, TiC, TiCN, TiB ₂ , SiC, Al ₂ O ₃ or a combination thereof. ing. All ceramic coatings are oxidation resistant coatings and are coated by chemical vapor deposition or physical vapor deposition. Here, the vapor deposition method includes chemical vapor deposition as well as physical vapor deposition in which a small piece of metal or nonmetal is heated and vaporized in a high vacuum to be vapor-deposited on the surface of glass, a crystal plate, or the like.

Generally, when a plunger with Ni self-fluxing alloy coated on the entire glass contact area is used, a small amount of metal oxide is produced by contact with high temperature glass, which peels off and adheres to the parison and blows the parison. Also remains attached to the inner surface of the bottle. Then, due to the difference in the expansion coefficient between the glass and the metal oxide at the stage of cooling after molding, the tensile force acting on the glass to which the metal oxide is attached causes the crack to grow from the metal oxide as a starting point.

On the other hand, when the entire surface of the glass contact portion is coated with ceramic, the above-mentioned peeled material is not generated because the ceramic has excellent heat resistance. However, since the hardness of ceramics is as high as Hv1000 or more, the glass on the inner surface of the mouth of the glass bottle is scraped by the ceramic on the surface of the plunger when the plunger descends, and the inner surface of the mouth is scratched in the vertical direction with a length of several hundred microns. Easy to get on. This scratch on the inner surface of the mouth does not directly lead to a decrease in strength because the mouth is thick, but it does not lead to a decrease in commercial value by reflecting light rays, and it is an obstacle to detecting other mouth defects. Become.

However, in the second embodiment, the mouth forming portion is coated with a self-fluxing alloy (which may be Ni-based or Co-based), and the tip side of the coating is ceramic coating, so that the mouth defect of the first embodiment can be suppressed. . That is, since the high temperature end is made of ceramic coating, it is possible to secure oxidation resistance and wear resistance even when it contacts glass at 1000 ° C. or higher. On the other hand, since the mouth part is about 500 ° C., the self-fluxing alloy coating has sufficient oxidation resistance and wear resistance at about 500 ° C. and does not cause a problem. The hardness of the self-fluxing alloy is Hv
The reason why it is set to 800 or less is that coating with a harder alloy may scrape off the inner surface of the mouth of the parison when the plunger 1 descends.

A test was conducted to confirm the effect of the second embodiment. First, the mouth molding part is coated with a chromium-nickel-boron-based self-fluxing alloy, and the tip side is coated with plunger A, and the mouth molding part is coated with the same self-fluxing alloy as described above. Al part
Plunger B coated with ₂ O ₃ and Ni as a whole
A plunger C coated with a self-fluxing alloy was prepared, each plunger was attached to a different section of an IS machine, and press-blow molding of a juice bottle having a capacity of 300 ml was continuously performed. As a result, the strength of the molded glass bottle was as follows.

In addition, a plunger D of a comparative example, which was entirely coated with TiN ceramic, was prepared, and it was attached to a different section of the IS machine together with the plunger A of the second embodiment, and a juice bottle with a narrow mouth screw and a mouth portion for one-touch cap were prepared. Press-blow molding of mochi juice bottle was performed.
When the incidence of defective cutting of the mouth due to the scratches on the inner surface of the mouth of the molded glass bottle was examined by tabulation for 2 days, it was as follows.

As can be seen from the above, according to the second embodiment, it is possible to drastically destroy the inner surface defect of the mouth portion while maintaining the impact strength of the glass bottle at the same level as in the first embodiment.

Third Embodiment FIGS. 7 and 8 show a plunger 1 used in a third embodiment of the present invention, and the parts other than the plunger conform to the first embodiment.

In the example of FIG. 7, while the plunger 1 is held at a position lower than the position 20 mm above the top of the positioner 20 and protruding, an air curtain that covers the entire plunger is formed by the air ejected from the base of the plunger 1. A parison is formed by using the plunger 1 in which foreign matter is prevented from adhering to the outer surface by the air curtain, and the obtained parison is blow-molded by a conventional method.

The reason why the plunger is covered with the air curtain is to prevent oil smoke, fume, mist and the like from adhering to the plunger 1. That is, if foreign matter adheres to the surface of the plunger, it will transform into a parison and reduce the impact strength of the glass bottle.

The air for forming the air curtain is ejected from the base of the plunger because if it is ejected from the vicinity of the top of the positioner, it will not be able to completely enclose the plunger due to the inclusion of external air or turbulent flow. .

In addition, it is held at a position lower than the position protruding by 20 mm.
This is because the tip of the plunger cannot be covered with the air curtain any more.

To explain the embodiment of FIG. 7 in more detail, 1 is a plunger, 17 is an elevating head of an elevating mechanism, and the plunger 1 is attached to the upper end of the elevating head 17 by a split ring 19 together with a cooling pipe 18 inside thereof. Then, the inside of the positioner 20 is moved up and down to press-mold the parison together with the mouth die and the rough die. Split ring 19
Holes 21 are formed in the hole 21. The compressed air supplied from below the positioner 20 is ejected from the cooling pipe 18 into the plunger 1, and after cooling the plunger 1, the compressed air is discharged from these holes 21. Has become.

In the base of the plunger 1, a plurality of vertical holes 22 which are evenly arranged in the circumferential direction are vertically formed, and a part of the compressed air for cooling is ejected from the vertical hole 22 to the periphery of the plunger 1 to generate air. It has a structure that forms a curtain.

In the example of FIG. 8, a lateral hole 23 is horizontally formed in the base of the plunger 1, and a part of the compressed air for cooling is provided in the lateral hole 23.
The air curtain is ejected to form an air curtain. Since the air curtain in this case is formed by the air that has collided with the inner surface of the positioner 20 and has been made to flow upward, it is possible to cover the plunger 1 more uniformly. The horizontal hole 23 is not limited to be horizontal and may be formed obliquely upward.

Also, a filter may be installed inside the plunger mechanism so as to keep the compressed air itself clean. To completely cover the entire plunger 1, positioner 20
The flow rate of the air curtain near the top of the is set to 0.5 m / sec or more, preferably 1 to 3 m / sec.

IS with a plunger mechanism having the structure shown in FIG.
A thin glass bottle having a weight of 170 gr and an internal capacity of 300 cc was press blow-molded by a mold glass molding machine. The flow velocity of the air curtain was 2.5 m / sec near the top of the positioner, and the internal cooling air was used as it was to form the air curtain. Adjusted so that the position is 20mm up from the top of the positioner. As a result of measuring the impact strength of 10 glass bottles obtained, the average was 19.0 in · lbs, and the variation was 15.0 in · lbs ~ 2
The strength was 0.3 in.lbs, which was about 7.7 in.lbs when the air curtain was not formed, and about 2.5 times stronger than the variation of 4.0 in.lbs to 9.0 in.lbs.

Basically, a combination of the carbon film formation by the flame injection of hydrocarbon described in the first embodiment, the formation of the wear resistant film on the sliding surface of the positioner, and the formation of the oxidation resistant film on the plunger surface is used. The means for further increasing the impact strength is the second and third embodiments.

The increase in impact strength of the glass bottle in the case where all of these were carried out at the same time (first embodiment + third embodiment, or second embodiment + third embodiment) was examined using a vial bottle having a capacity of 200 cc and a thickness of 2.2 mm. Then, the results shown in FIG. 9 were obtained. FIG. 9 also shows the strength obtained by the conventional molding method for reference. 9th
As is clear from the figure, the impact strength is more than doubled, the variation is small, the minimum strength is increased, and the reliability is increased.

[Effects of the Invention] According to the present invention of claims 1 and 3, the effect that the impact strength of the glass bottle is about twice that of the conventional one, the variation in the impact strength is reduced, and the reliability in strength is increased. obtain.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, it is possible to obtain the effect that the inner surface defects of the bottle mouth portion which appear when the entire surface of the plunger is ceramic-coated can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a section of an IS glass molding machine during the formation of a carbon film in the glass bottle manufacturing method according to the first embodiment of the present invention, and FIG. 2 is the glass according to the first embodiment of the present invention. FIG. 3 is a sectional view of the device during parison molding by the bottle manufacturing method, FIG. 3 is a front view of a positioner portion of the device used in the glass bottle manufacturing method according to the first embodiment of the present invention, and FIG. The front view of the Co-based self-fluxing alloy spray coating plunger used in the glass bottle manufacturing method according to the embodiment, FIG. 5 is the impact strength-cumulative damage ratio chart of the glass bottle manufactured in the first embodiment of the present invention, FIG. 6 is a front view of a ceramic / self-fluxing alloy coating plunger used in the glass bottle manufacturing method according to the second embodiment of the present invention, and FIG. 7 is an air curtain for the glass bottle manufacturing method according to the third embodiment of the present invention. Injecting forming air from the vertical hole FIG. 8 is a cross-sectional view of the device in a state of being ejected, FIG. 8 is a cross-sectional view of the device in a state of ejecting air for forming an air curtain from a lateral hole in the glass bottle manufacturing method according to the third embodiment of the present invention, The figure is a characteristic diagram of the impact strength of a glass bottle when any one of the first and second examples and the third example is carried out. 1 …… Plunger 2 …… Self-fluxing alloy coating 3 …… Ceramic coating 10 …… Mouth type 11 …… Guide ring 12 …… Coarse type 13 …… Baffle 14 …… Nozzle 15 …… Parison 20 …… Positioner 22 …… Vertical hole 23 …… Horizontal hole 24 …… Bushing 25 …… Spring guide 30 …… Abrasion resistant coating

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masato Hayashi 2-chome, Kamogawa-cho, Minokamo City, Gifu Prefecture (56) References JP-A-1-197334 (JP, A) JP-A-62-185851 (JP, A) Japanese Patent Sho 60-56756 (JP, B2) Japanese Special Sho 63-502891 (JP, A)

Claims (3)

[Claims] 1. A sliding surface between a bushing and a spring guide of a positioner that guides up and down movement of a plunger using a metal plunger having a thermal spray coating of a Co-based self-fluxing alloy on at least a portion that contacts the parison during molding of the parison. A wear-resistant coating is formed on the surface of the rough die and mouth die using a positioner that prevents the generation of sliding powder on the bushings and spring guides by this wear-resistant coating.
A parison is formed by periodically injecting 0.75 or more gaseous hydrocarbons or a mixture of two or more gaseous hydrocarbons with a flame to form a carbon film for lubrication. The method for producing a glass bottle having high impact strength is characterized in that it is blow-molded by. 2. A metal plunger having a mouth part of a plunger body for molding a parison coated with a self-fluxing alloy of Hv800 or less, and a tip portion of which is ceramic-coated by a chemical vapor deposition method or a physical vapor deposition method, Of the positioner that guides the lifting and lowering of the plunger,
A wear resistant coating is formed on the sliding surface between the bushing and spring guide, and this wear resistant coating prevents the generation of sliding powder on the bushing and spring guide. A parison is formed by forming a carbon film for lubrication by periodically flame-injecting a gaseous hydrocarbon having a ratio of / H of 0.75 or more or a mixture of two or more types of gaseous hydrocarbons. A method for producing a glass bottle having high impact strength, which comprises blow molding a parison by a conventional method. 3. An air curtain that covers the entire plunger is formed by the air ejected from the base of the plunger while the plunger is held below the position 20 mm above the top of the positioner that guides the elevation of the plunger. The parison is formed by using a plunger in which foreign matter is prevented from adhering to the outer surface.
A method for producing a glass bottle having high impact strength according to any one of 1.