Method for blowing and cooling glass containers, blower and glass container forming machine

Abstract

The invention relates to a method and a blower for blowing and cooling glass containers (1). The method comprises introducing a gob of molten glass in a preparatory mold, deforming the gob of glass to obtain a preform, transferring the preform to a blowing mold (220), placing a blower (300) above the blowing mold (220) and introducing air inside the preform to obtain a glass container (1) with a final shape, introducing liquid water with a total level of solids less than or equal to 25 ppm in the glass container (1) to cool same, withdrawing the blower (300) by separating it from the blowing mold (220), and removing the glass container (1) from the blowing mold (220). The invention also relates to a glass container forming machine comprising the blower (300).

Description

[0001] DESCRIPTION

[0002] Procedure for blowing and cooling glass containers, glass container blowing and forming machine

[0003] TECHNICAL SECTOR

[0004] The present invention relates to the manufacture of glass containers, wherein the glass containers are cooled with liquid water in the blow molds of the forming machine to increase the production speed and reduce the occurrence of defects.

[0005] PRIOR STATE OF THE ART

[0006] Glass containers are manufactured on a manufacturing line with a hot zone and a cold zone. The hot zone begins in a furnace, where raw materials (typically including sand, soda ash, limestone, and recycled glass) are melted into molten glass. The molten glass is then cut into gobs, and a distributor directs the gobs by gravity to a forming machine, called an individual section forming machine (IS), where the glass containers are formed using a press-blow or blow-blow process.

[0007] Each drop falls into a preparation mold on the forming machine, where a preform called a parison is formed. The parison is formed using a plunger that pushes the molten glass into the preparation mold, or by blowing the glass to take the shape of the interior of the preparation mold. The parison is inverted and transferred to a blow mold, where a blower forces air into the parison to give it the final shape of the glass container.

[0008] The glass containers are extracted to a dead plate and then directed to the last part of the hot zone, where a "Lehr" annealing furnace heats the glass containers and then slowly cools them over a set period of time, for example, one hour, subjecting the glass to an annealing process that reduces internal stresses and the likelihood of breakage. In the cold zone, the containers are inspected for defects such as cracks, scale, bubbles, or excessively thin walls, and finally, the glass containers are sent to a packaging area.

[0009] It is well known to cool glass containers in the hot zone before the annealing furnace to increase production speed. For example, blow molds with cooling systems are known to cool the glass container formed inside the blow mold from the outside. It is also known to cool the glass container after removal from the blow mold, for example, using cryogenic fluids or air currents.

[0010] Document US3235353A shows a blow molding machine for introducing air into a parison to form a glass container, and also for cooling the glass container directly within the blow mold by introducing water into the container.

[0011] EXPOSURE OF THE INVENTION

[0012] The object of the invention is to provide a method for blowing and cooling glass containers, a blowing machine for introducing water and air into the glass containers and a glass container forming machine incorporating said blowing machines, as defined in the claims.

[0013] An aspect of the invention relates to a method for blowing and cooling glass containers comprising the steps of: introducing a gob of molten glass into a preparation mold having a cavity with an initial container shape, deforming the gob of glass within the cavity of the preparation mold to obtain a preform with the shape of the initial container, transferring the preform to a blow mold having a cavity with a final container shape, positioning a blower over the blow mold and introducing air into the preform to expand the preform and obtain a glass container with the shape of the final container, introducing liquid water into the glass container that is inside the blow mold to cool the glass container, withdrawing the blower by separating it from the blow mold, and removing the glass container from the blow mold,where the liquid water introduced into the glass container has a total dissolved solids level in the liquid water equal to or less than 25 ppm.,

[0014] Another aspect of the invention relates to a blowing machine for introducing air into a preform located in a blow mold and expanding the preform to obtain a glass container, the blowing machine comprising: at least one blowing air inlet for introducing air into the preform and obtaining the glass container, or the blowing air inlet is communicated with a blowing air passage extending from the blowing air inlet to a lower end of the blowing machine which is arranged on the blow mold, at least one water inlet for introducing liquid water into the glass container and cooling the glass container, or the water inlet is communicated with a water passage extending from the water inlet to the blowing air passage, and at least one exhaust with an outlet conduit for evacuating the steam generated when cooling the glass container,where the liquid water introduced into the glass container has a total dissolved solids level in the liquid water equal to or less than 25 ppm.,

[0015] Another aspect of the invention relates to a glass container forming machine comprising: preparation molds, each preparation mold having a cavity for receiving a drop of molten glass and obtaining a preform, blow molds, each blow mold having a cavity for receiving a preform and obtaining a glass container, transfer devices for transferring the preforms from the preparation molds to the blow molds, blowing machines, as defined above, for introducing air into the preforms and expanding the preforms to obtain the glass containers and for introducing liquid water into the glass containers and cooling the glass containers, an air supply for supplying air to the blowing machines, and a water supply for supplying liquid water to the blowing machines.

[0016] All of this increases manufacturing speed while minimizing the risk of defects. Introducing liquid water into the blow mold improves glass cooling, allowing for increased production speeds by eliminating or reducing annealing time in the Lehr furnace, in addition to reducing energy consumption. When liquid water comes into contact with molten glass at a high temperature (approximately 1000°C), it evaporates rapidly, generating a precipitation of the solids contained in the water that remain inside the glass container. A low concentration of solids, equal to or less than 25 ppm, reduces the risk that the precipitation of these solids from the water remaining inside the glass container could affect the composition of the glass after vitrification.

[0017] These and other advantages and features of the invention will become apparent from the figures and the detailed description of the invention.

[0018] DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 shows an example of a glass container manufacturing line.

[0020] Figure 2 shows an example of a glass container forming machine according to the invention.

[0021] Figure 3 shows an example of a blowing machine for forming and cooling a glass container according to the invention.

[0022] Figure 3a shows an enlarged detail of the blower in Figure 3.

[0023] Figure 4 shows an example of the water supply to the machine in Figure 2.

[0024] Figure 5 shows an example of the valves used to control the flow of fluids through the blower inlets and outlets.

[0025] Figure 6 shows a diagram of the events that occurred during a complete blowing and cooling cycle of a glass container.

[0026] DETAILED EXPLANATION OF THE INVENTION

[0027] Figure 1 shows an example of a manufacturing line 100 for glass containers 1. The line comprises a raw material receiving area 110 where the raw materials with which the glass containers 1 are manufactured are received, a melting area 120 where the raw materials are melted to obtain molten glass, a forming area 130 where the molten glass is transformed into the glass containers 1, a treatment area 140 where the containers 1 are heat and surface treated to prevent the formation of internal stresses and provide the glass with a greater degree of resistance, an inspection area 150 where dimensional, functional and defect checks are carried out on the containers 1 to check that they comply with the required quality requirements, and a final packaging area 160 where the glass containers 1 are grouped on pallets for storage and transport.

[0028] In the receiving area 110, the raw materials are received and, by means of conveyor belts, are taken to hoppers that supply the raw materials to the melting area 120, which has a melting furnace where, by means of burners, the raw materials are melted at temperatures exceeding 1,000°C. Through distribution channels, the molten glass is supplied in the form of drops to the forming area 130, obtaining a glass container 1 with each drop of molten glass.

[0029] The transformation of the molten glass into glass containers, in the forming area 130, is carried out with forming machines 200 (called IS machines) that have a longitudinal arrangement with sections arranged in parallel, each section receiving at least one drop of molten glass, and each drop is converted into a preform and subsequently into a glass container 1 in a process called blow-pressing or blow-blowing.

[0030] The grouped containers 1 are sent to the treatment zone 140, which has an annealing tunnel or "Lehr" that separates the container manufacturing line 100 into a hot zone and a cold zone. The hot zone extends from the melting zone furnace 120 to the treatment zone annealing tunnel 140, and the cold zone extends from the treatment zone annealing tunnel 140 to the end of the manufacturing line, in the final packaging zone 160.

[0031] Thus, upon exiting the forming machine 200, the glass containers 1 are at a temperature above 650°C, and to prevent the formation of internal stresses, they are taken to the annealing tunnel or "Lehr", through which the glass containers 1 slowly pass, being reheated and subsequently cooled. In the treatment zone 140, the containers undergo various treatments. Subsequently, the glass containers 1 are transferred to the inspection zone 150, where dimensional, functional, and defect checks are performed on the containers 1 to verify that they meet the required quality requirements, before finally sending the containers 1 to the final packaging zone 160.

[0032] Figure 2 shows an example of a forming machine 200 for glass containers 1. The forming machine 200 has preparation molds 210 and blow molds 220. Each preparation mold 210 has a cavity for receiving a drop of molten glass to obtain a preform (called a parison), and each blow mold 220 has a cavity for receiving a preform to obtain a glass container 1. The machine 200 has transfer devices 230 (called inverts) for transferring the preforms from the preparation molds 210 to the blow molds 220 and blow molds 300 (see Figure 3) for introducing air into the preforms and expanding the preforms to obtain the glass containers 1 and for introducing liquid water into the glass containers 1 and cooling the glass containers 1.The machine additionally comprises an air supply 500 for supplying air to the blowers 300 and a water supply 400 for supplying liquid water to the blowers 300 (see Figures 4 and 5).

[0033] The forming machine 200 shown in the example of Figure 2 has 12 double-gob sections, and each section has two preparation molds 210 and two blow molds 220, however, it could be a machine with a different number of sections and / or with a different number of preparation and blow molds per section. For example, each section of the machine 200 may be a single-gob, with a single preparation mold and a single blow mold, or each section may be up to a quadruple-gob, with four separation molds and four blow molds.

[0034] The glass containers 1 are removed from the blow molds 220 by means of a gripper (not shown) which places the glass containers 1 on the dead plate 240 and a pusher 250 pushes the glass containers 1 onto a conveyor belt 260 which directs the glass containers 1 towards the next zone of the line 100, which may be the annealing tunnel of the treatment zone 140 where the cooling of the containers 1 may continue. According to the invention, the cooling carried out in the blow molds 220 with the liquid water makes it possible to considerably reduce the cooling time in the annealing tunnel and thus the total production time of the glass containers 1.

[0035] According to the invention, the liquid water introduced into the glass container has a total dissolved solids level equal to or less than 25 ppm. The liquid water with a low dissolved solids content allows the glass container 1 to be cooled within the blow mold 220, preventing any solids contained in the water from becoming encrusted on the glass.

[0036] For the purposes of the invention, ppm (parts per million) refers to the milligrams of solids present per liter of water. That is, the liquid water used to cool the glass container has 25 milligrams or less of solids per liter of water.

[0037] Preferably, the liquid water is introduced into the glass container at a temperature equal to or greater than 50°C, so that hot water is used and the risk of causing a thermal shock between the temperature of the glass and the temperature of the water, which causes breakage in the glass, is reduced.

[0038] Even more preferably, the liquid water is introduced into the glass container at a temperature between 50-150°C.

[0039] When glass is molten, there is no risk of breakage, but when it begins to vitrify, the risk of breakage increases. In the case of a glass container, the risk is greatest at the mouth of the container, which is the part that first begins to cool. Therefore, introducing water at a temperature below 50°C increases the risk of breakage at the mouth of the container and causes small glass particles to become loose inside the container, a critical failure since glass containers are intended to hold products for human consumption. On the other hand, a temperature above 150°C causes a loss of efficiency when it comes to stealing heat from the molten glass, since the water quickly turns to steam, which has a lower cooling capacity than liquid water.

[0040] Furthermore, the selected temperature range of 50-150°C allows the water to efficiently draw heat from the glass when it comes into contact with the molten glass without damaging it. It also transforms into steam, reducing the risk of small particles of water or moisture falling into the container when it is removed from the blow mold.

[0041] Typically, a glass bottle manufacturing plant has a supply of reverse osmosis water (with a total dissolved solids level greater than 30 ppm) for the various processes carried out in the plant. Manufacturing glass containers with this reverse osmosis water at room temperature of approximately 25°C generated limescale deposits both in the blowing machine and on the bottom of the container. Furthermore, with this water at 25°C, the mouths of the containers became cracked due to thermal shock during water evaporation.

[0042] It has been proven that introducing liquid water into the glass container at a temperature equal to or greater than 50°C and with a total level of dissolved solids in the liquid water less than or equal to 25 ppm increases the manufacturing speed of glass containers, minimizing the risk of cracks and optimizing the energy cost of the process.

[0043] The best results are obtained with hot water between 80-100°C and a solids content of less than 5 ppm. For example, it has been observed that with hot water at approximately 90°C, thermal shock is significantly reduced and cracking is almost nonexistent. Furthermore, it has been observed that reducing the solids content in the water to approximately 3 ppm prevents particle deposits.

[0044] Additionally, the blow mold 220 may have cooling means that indirectly cool the glass container 1 from the outside.

[0045] The blowing machine 300 comprises a blowing air inlet 301 for introducing air into the preform and obtaining the glass container 1, a water inlet 302 for introducing liquid water into the glass container 1 and cooling the glass container 1, and an exhaust 303 with an outlet duct 321 for evacuating the steam generated when cooling the glass container.

[0046] As shown in the example of Figure 3, the blower 300 introduces air and liquid water into two blow molds 220, which are located in one of the sections of the forming machine 200 of Figure 2. In this case, each section of the machine 200 is a double drop section and has a blower 300 with a blow air inlet 301 common to both blow molds 220, and a water inlet 302 and an exhaust 303 for each blow mold 220.

[0047] As can be seen in detail in Figure 3a, the blowing air inlet 301 is communicated with a blowing air passage 304 extending from the blowing air inlet 301 to a lower end 305 of the blower 300 which is arranged on the blow mold 220. The water inlet 302 is communicated with a water passage 306 extending from the water inlet 302 to the blowing air passage 304, so that water is mixed with the blowing air in the blowing air passage 304 to obtain water particles which are introduced into the glass container 1 by cooling it.

[0048] The blower 300 further comprises a cooling air inlet 307 for cooling the external surface of the mouth 2 of the glass container 1. The cooling air inlet 307 is communicated with a cooling air passage 308 extending from the cooling air inlet 307 to an annular chamber 309 which is arranged at the lower end 305 of the blower 300.

[0049] The blow molding machine 300 comprises a blow molding machine body 310, a blow head 311 disposed at the lower end 305 of the blow molding machine 300, a support arm 313 which is connected to the blow molding machine body 310 and the blow head 311, and a support arm 313 which is connected to the blow molding machine body 310 for vertically moving the blow molding machine 300 toward and away from the blow mold 220.

[0050] In the example of Figure 3, which shows a blower 300 for a double drop section, the blower 300 comprises a blower body 310 and two supports 312 of two blow heads 311, and each blow head 311 is configured to be arranged on a respective blow mold 220.

[0051] The blowing machine body 310 comprises the blowing air inlet 301, the water inlet 302 and the cooling air inlet 307. The blowing machine body 310 has intake ports for receiving the air and water used to form and cool the glass containers. The support 312 of the blowing head 311 has a first part that is partially inserted into the blowing machine body 310 and a second part that embraces the blowing head 311, holding it. For example, the connection between the parts of the blowing machine 300 can be established by means of threaded connections.The first support part 312 has a side hole 315 communicating the blowing air inlet 301 with the blowing air passage 304 and a first annular manifold 316 which is located at the upper end of the first part and communicating the cooling air inlet 307 with a first conduit 317 extending along the support 312 of the blowing head 311 from the first annular manifold 316 to the lower end of the first support part 312.

[0052] The blow head 311 has a second annular manifold 318 located at the upper end of the blow head 311 and a second conduit 319 extending from the second annular manifold 318 to the annular chamber 309 of the lower end 305 of the blower 300, the first conduit 317 of the support 312 of the blow head 311 being in communication with the second manifold 318 of the blow head 311.

[0053] In this way, the cooling air passage 308 is formed by the first annular collector 316 and the first conduit 317 of the support 312 of the blowing head 311, and by the second annular collector, the second conduit 319 and the annular chamber 309 of the blowing head.

[0054] 311.

[0055] As indicated above, the blow molding machine 300 shown in Figure 3 introduces water and air into two blow molds 220, such that the blow air passage 304 has a first part with an inverted T shape to direct the air from the blow air inlet 301 towards each blow head 311. Similarly, the cooling air passage 308 has a first part with an inverted T shape to direct the air from the cooling air inlet 307 towards each blow head 311, specifically the cooling air inlet 307 is connected with the annular manifold 316 of each support

[0056] 312.

[0057] The annular chamber 309 has a plurality of holes 320 for directing the cooling air onto the external surface of the mouth 2 of the glass container 1, thereby obtaining a plurality of air projections directed towards the mouth 2.

[0058] As seen in Figures 3 and 3a, the outlet duct 321 of the exhaust 303 is connected to the lower end 305 of the blower 300 which is in contact with the blow mold 220 to evacuate the vapor that is generated during the formation of the glass container and during cooling.

[0059] Preferably, the outlet duct 321 of the exhaust 303 has a bent area 322 that prevents the return of water particles to the blower 300. Said bent area acts as a siphon and the water particles that have not been transformed into steam are trapped in the bent area, preventing their return to the blower 300. In this way, it is prevented that water drops can fall on the vitrified glass once the blower 300 has been removed from the blow mold 220.

[0060] Preferably, the outlet duct 321 of the exhaust 303 has a slope with a downward inclination that prevents the return of water particles to the blower 300.

[0061] Even more preferably, as seen in Figure 3a, the slope with the downward inclination of the outlet conduit 321 is located between the lower end 305 of the blower 300 and the bent area 322. In this way, the water particles that have not been transformed into steam and that are deposited in the outlet conduit 321 tend to slide down the slope of the conduit 321 and fall into the bent area 322, where they are retained.

[0062] As seen in Figure 3a, the water passageway 306 has sections 323, and each section 323 has a diameter. The diameter of the sections 323 decreases between the water inlet 302 and the blow-off air passageway 304, such that the velocity of the water accelerates as it travels through the sections 323 of the water passageway 306 so that the water is introduced in an atomized form into the blow-off air passageway 304.

[0063] Preferably, the blow air passage 304 has a first tube 324 that directs the blow air into the preform and the water passage 306 has a second tube 325 that introduces liquid water into the first tube 324, the first tube 324 having a first diameter and the second tube 325 having a second diameter, the first diameter of the first tube 324 being larger than the second diameter of the second tube 325, and the first tube 324 and the second tube 325 being coaxial. The second diameter of the second tube 325 is selected to be small in size to prevent dripping of any excess water particles that may remain inside the tube 325 after the water injection has stopped. Preferably, and as shown schematically in Figure 3, the support arm 313 is actuated by an electric motor 314 that vertically moves the blower 300 towards and away from the blow mold 220.In this way, the risk of damaging the mouth 2 of the glass container 1 is minimized, since the electric motor allows the movements of the blower to be adequately controlled, which is not possible with other types of drives, such as pneumatic drives. Pneumatic drives cause sudden movements, and above all, they cause impacts at the final ends of the travel path of the blower 300, and over time, due to the impacts, clearances are generated in the elements that make up the drive. This is especially relevant when using the first tube 325, which is arranged inside the glass container 1 during air injection, and must remain outside the glass container 1 when the container 1 is removed from the blow mold 220, so a correct movement of the first tube 325 is preferable so that it does not hit the mouth 2.

[0064] Preferably, the exhaust 303 is connected to the water inlet 302 to reintroduce into the blower 300 hot water recovered from the steam generated when cooling the glass container 1. This allows the hot water from the cooling process to be reused, avoiding the energy expenditure of having to reheat it, and also ensures the reintroduction of water with a low solids content, thus making the process more energy efficient.

[0065] As shown in the example of Figure 4, the water supply 400 of the machine 200 comprises an industrial water supply source 401, a demineralizer 402 connected to the industrial water supply source 401 for obtaining liquid water with a total dissolved solids level in the liquid water equal to or less than 25 ppm, a first water tank 403 connected to the demineralizer 402 for storing the liquid water, a pump 404 connected to the first water tank 403 for pressurizing the liquid water, a second water tank 405 connected to the outlet of the pump 404 for storing the pressurized liquid water, and a heater 406 for heating the pressurized liquid water from the second tank 405 that is supplied to the blowers 300.

[0066] Preferably, liquid water with a total dissolved solids level of less than or equal to 25 ppm is obtained by filtering industrial water in the demineralizer 402. For example, the industrial water may contain a total dissolved solids level of greater than 100 ppm. However, the solids in the water may be reduced by other chemical methods, or by biological or physical methods, or water with the required total solids level may be used directly instead of industrial water.

[0067] Additionally, the water supply 400 comprises a heat exchanger 407 having an inlet connected to the exhausts 303 of the blowers 300, a first outlet connected to the first water tank 403 and a second outlet connected to the outside atmosphere, such that the steam extracted from the exhausts 303 is directed to the heat exchanger 407 where said steam is decomposed into air and hot water that is stored in the first water tank 403. The heat exchanger 407 uses a source of cold water 408 to condense the steam and separate it into air and hot water.

[0068] Generally the recovered hot water is not enough to refill the first water tank 403 and repeat the cooling process for several cycles, since there are slight losses, therefore it is necessary to feed the tank 403 with the industrial water supply source 401. Accordingly, to control the amount of water that has to be demineralized and introduced into the water tank 403, a level detector 409 is used, such as a float valve.

[0069] The heater 406 of the second tank 405 is optional in case of recovering hot water through the exhaust 303 of the blowers 300. In such case, the temperature of the recovered hot water may be sufficient to heat the water that will be reintroduced into the new glass containers 1, or at least it may be sufficient to significantly reduce the energy consumption of the heater 406.

[0070] Pump 404 raises the pressure in the second water tank 405 to at least 5 bars to obtain hot water at the outlet of the second tank 405 of at least 120 °C, however, pump 404 can apply pressures greater than 5 bars in case temperatures greater than 120 °C are required to achieve faster evaporation of the water.

[0071] The machine 200 comprises four valves for each of the blowers 300 to control the inlet and outlet fluids of the blowing and cooling process of the glass containers. As shown in the example of Figure 5, each blower 300 comprises a first valve 501 to control the passage of blowing air at the blowing air inlet 301, a second valve 502 to control the passage of water at the water inlet 302, a third valve 503 to control the passage of steam at the exhaust 303, and a fourth valve 504 to control the passage of cooling air at the cooling air inlet 307.Each inlet 301, 302 and 307 and each outlet 303 of the blower 300 is controlled independently, so that in the blower 300 shown in Figure 3, which shows two blow molds 220, a single valve 501 is used to regulate the blowing air, a single valve 504 is used to regulate the cooling air, and two valves 502 are used to regulate the water introduced into each glass container and two valves 503 are used to regulate the steam extracted from each glass container.

[0072] Preferably, the third valve 503 is a valve with electronically controllable opening. That is, the valve does not only have two states: open and closed, but can also regulate the percentage of steam extracted through the exhaust 303. Thus, the pressure inside the glass vessel 1 can be controlled at all times when the blower 300 is positioned over the blow mold 220.

[0073] A timing diagram of the events occurring on the blow mold 220 side of the forming machine 200 is shown in Figure 6. The diagram illustrates the blowing and cooling process from the time the preform is introduced into the blow mold 220 until the formed glass container 1 is withdrawn to the dead plate 240, and then a new preform is introduced into the blow mold for the formation of another glass container. The time is defined in machine degrees, and 360 degrees are represented which represent one complete cycle of the forming machine 200.

[0074] The process on the blow mold 220 side begins when the transfer device 230 transfers a preform from the preparation mold 210 to the blow mold 220, this process is called reversing. In this position, the open blow mold 220 begins to close, and the transfer device 230 releases the preform and returns to the preparation mold 210 side. In the diagram in Figure 6, the closed blow mold 220 with the preform inside it and the blow molder 300 in the lower position arranged above the blow mold 220 are shown at level 0.

[0075] When the blow mold 220 is closed, the blow mold 300 descends from an upper position to a lower position on the blow mold 220, as shown in Figure 3. This movement is generally performed slowly since the preform needs to elongate until it touches the bottom of the blow mold 220 and is ready to be inflated.

[0076] When the blower is in the lower position, air is first introduced into the preform to expand the preform and obtain the glass container 1, (which is referred to as blowing air 1 in the diagram), and then liquid water is introduced into the glass container 1 to cool it (which is referred to as water in the diagram).

[0077] Preferably, the air to expand the preform is introduced at a pressure of between 1 bar and 3 bar. Preferably, liquid water is introduced into the glass container 1 at a pressure of at least 3 bar.

[0078] Preferably, liquid water is introduced into the glass container 1 together with air. The air allows the liquid water to transform into water particles, which is better for cooling the glass than if only liquid water were introduced in the absence of air.

[0079] When air is introduced into the preform to expand the preform, the blow mold cavity 220 is at a first pressure, and when air, along with liquid water for cooling the glass container, is introduced into the glass container, the blow mold cavity 220 is at a second pressure, the first pressure being greater than the second pressure. This is because more pressure is generally required within the cavity to expand the glass. Essentially, the pressure within the blow mold is regulated by valve 503 of exhaust 303.

[0080] As illustrated in Figure 6, exhaust 303 is opened after water has begun to be introduced to remove the air / water vapor mixture resulting from the heat exchange, however, exhaust 303 may be opened before water has begun to be introduced. For example, exhaust 303 may be opened 15 machine degrees before, or 15 machine degrees after, water has begun to be introduced.

[0081] Preferably, air introduction is maintained after the introduction of liquid water ceases. This prevents water particles from remaining inside the blower and dripping onto the hot glass when the blower is removed from the blow mold. For example, air introduction can be maintained at least 10 machine degrees after the introduction of water ceases. Cooling air is preferably introduced into the annular chamber 309 of the blower to cool the outer surface of the mouth 2 of the glass vessel 1. The pressure in the annular chamber 309 is greater than the pressure inside the glass vessel 1 to prevent liquid water introduced into the glass vessel 1 from transferring into the annular chamber 309.As shown in Figure 3a, when the head 311 of the blowing machine 300 is arranged over the blowing mold 220, there is a minimum space between the upper part of the mouth 2 of the glass container 1 and the upper wall of the annular chamber 309 of the blowing machine, since if the blowing machine physically touches the glass, defects may occur in the mouth. Given the pressure at which the liquid water is introduced, small particles of water may filter through this space and contact the outside of the mouth 2 of the container 1, and since this area is the first to vitrify, a thermal shock may occur that generates breakages, however, increasing the pressure in the annular chamber 309 prevents the transfer of water from the inside of the container 1 to the annular chamber 309.

[0082] Preferably, the cooling air and the preform-expanding air are introduced simultaneously. This prevents internal fluids, which may contain traces of water from the formation of the previous container, from leaking into the aforementioned space when the preform-expanding air begins to be introduced. As can be seen in Figure 6, the cooling air and the preform-expanding air begin to be introduced at the same time, and both are stopped at the same time. This ensures that the pressure in the annular chamber 309 is always greater than the pressure within the mold 220 during the introduction of the air and water.

[0083] The exhaust 303 remains open after the air and water supply has ceased, and remains open until at least the blower 300 withdraws from the blow mold 220. However, Figure 6 shows that the exhaust 303 remains open until a few moments after the blow mold is closed again to expand a new glass container.

[0084] Once the blow mold 220 begins to open, a removal mechanism is activated that holds the glass container 1 by the mouth 2 to prevent it from moving. Once the blow mold 220 has fully opened, the removal mechanism transfers the glass container 1 to the sample plate 240. Preferably, after removing the blow mold 300 and separating it from the blow mold 220, air is again introduced into the blow mold 300 to remove any water residue in the blow mold. As shown in Figure 6, after opening the blow mold 220 and removing the glass container 1, air is again introduced through the blow air passage 304 and through the cooling air passage 308 to eliminate any water residue that may remain in the blow mold 300. In this way, the blow mold 300 is ready to form and cool a new preform.In the diagram in Figure 6, this new air introduction is referred to as blow air 2 and cooling air 2.

Claims

CLAIMS 1. A method for blowing and cooling glass containers, comprising the steps of: introducing a molten glass drop into a preparation mold (210) having a cavity with an initial container shape, deforming the glass drop within the cavity of the preparation mold (210) to obtain a preform with the initial container shape, transferring the preform to a blow mold (220) having a cavity with a final container shape, positioning a blower (300) over the blow mold (220) and introducing air into the preform to expand the preform and obtain a glass container (1) with the final container shape, introducing liquid water into the glass container (1) that is inside the blow mold (220) to cool the glass container (1), removing the blower (300) by separating it from the blow mold (220), and removing the glass container (1) from the blow mold (220),characterized in that the liquid water introduced into the glass container (1) has a total level of dissolved solids in the liquid water less than or equal to 25 ppm., 2. Method according to claim 1, wherein the liquid water is introduced into the glass container (1) at a temperature equal to or greater than 50°C.

3. Method according to the preceding claim, wherein the liquid water is introduced into the glass container (1) at a temperature between 50-150°C.

4. Method according to any of the preceding claims, wherein the liquid water is introduced into the glass container (1) at a pressure of at least 3 bars.

5. Method according to any of the preceding claims, wherein the air to expand the preform is introduced at a pressure of between 1 bar and 3 bars.

6. Method according to any of the preceding claims, wherein air is first introduced into the preform to expand the preform and obtain the glass container (1), and subsequently liquid water is introduced into the glass container (1) to cool it, and wherein the liquid water is introduced into the glass container (1). glass (1) together with air.

7. Method according to the preceding claim, wherein the introduction of air is maintained after ceasing to introduce liquid water.

8. Method according to claim 6 or 7, wherein when the air for expanding the preform is introduced into the preform, the blow mold cavity (220) is at a first pressure, and when the air together with the liquid water for cooling the glass container is introduced into the glass container, the blow mold cavity (220) is at a second pressure, the first pressure being greater than the second pressure.

9. Method according to any of the preceding claims, wherein after removing the blower (300) and separating it from the blow mold (220), air is again introduced into the blower (300) to remove water residues in the blower (300).

10. Method according to any of the preceding claims, wherein cooling air is introduced into an annular chamber (309) of the blower (300) to cool the external surface of the mouth (2) of the glass container (1), the pressure in the annular chamber (309) being greater than the pressure inside the glass container (1) to prevent liquid water from passing into the annular chamber (309).

11. Method according to the preceding claim, wherein the cooling air and the air for expanding the preform are introduced at the same time.

12. Method according to any of the preceding claims, wherein an electric motor (314) vertically moves the blower (300) to bring it closer to and separate it from the blow mold (220).

13. Method according to any of the preceding claims, wherein when cooling the glass container (1) steam is generated which is extracted through an exhaust (303) of the blower (300) and the steam is directed to a heat exchanger (407) where hot water is recovered from said steam, and said recovered hot water is recirculated to the blower (300) to cool a new glass container. glass (1).

14. Method according to any of the preceding claims, wherein the liquid water with the total level of dissolved solids in the liquid water less than or equal to 25 ppm is obtained by filtering industrial water in a demineralizer (402).

15. A blowing machine for introducing air into a preform located in a blow mold (220) and expanding the preform to obtain a glass container (1), the blowing machine (300) comprising: at least one blowing air inlet (301) for introducing air into the preform and obtaining the glass container (1), or the blowing air inlet (301) is communicated with a blowing air passage (304) extending from the blowing air inlet (301) to a lower end (305) of the blowing machine (300) which is arranged on the blow mold (220), at least one water inlet (302) for introducing liquid water into the glass container (1) and cooling the glass container (1), or the water inlet (302) is communicated with a water passage (306) extending from the water inlet (302) to the blowing air passage (304),and at least one exhaust (303) with an outlet pipe (321) to evacuate the steam generated when cooling the glass container (1), where the liquid water introduced into the glass container (1) has a total level of dissolved solids in the liquid water equal to or less than 25 ppm.

16. Blowing machine according to claim 15, wherein the liquid water introduced into the glass container (1) has a temperature equal to or greater than 50°C, preferably a temperature between 50-150°C.

17. Blow-moulding machine according to claim 15 or 16, comprising at least one cooling air inlet (307) for cooling the external surface of the mouth (2) of the glass container (1), the cooling air inlet (307) being communicated with a cooling air passage (308) extending from the cooling air inlet (307) to an annular chamber (309) which is arranged at the lower end (305) of the blow-moulding machine (300).

18. A blower according to the preceding claim, comprising: a blower body (310), the blower body (310) comprising the blowing air inlet (301), the water inlet (302) and the cooling air inlet (307), at least one blow head (311) disposed at the lower end (305) of the blower (300), at least one support (312) of the blow head (311) connecting the blower body (310) with the blow head (311), and a support arm (313) which is attached to the blower body (310) for vertically moving the blower (300) towards and away from the blow mold (220).

19. Blower according to the preceding claim, wherein the support arm (313) is actuated by an electric motor (314) that vertically moves the blower (300).

20. Blower according to claim 18 or 19, wherein: the support (312) of the blowing head (311) has a first part which is partially inserted into the blower body (310) and a second part which embraces the blowing head (311) holding it, the first support part (312) has a side hole (315) communicating the blowing air inlet (301) with the blowing air passage (304) and a first annular manifold (316) which is located at the upper end of the first support part (312) and which communicates the cooling air inlet (307) with a first conduit (317) which extends along the support (312) of the blowing head (311) from the first annular manifold (316) to the lower end of the second support part (312),and the blow head (311) has a second annular manifold (318) located at the upper end of the blow head (311) and a second conduit (319) extending from the second annular manifold (318) to the annular chamber (309) at the lower end (305) of the blower (300), the first conduit (317) of the support (312) of the blow head (311) being in communication with the second manifold (318) of the blow head (311).

21. Blower according to any of claims 17 to 20, wherein the chamber annular (309) has a plurality of holes (320) for directing cooling air onto the external surface of the mouth (2) of the glass container (1).

22. Blower according to any of claims 15 to 21, wherein the outlet duct (321) of the exhaust (303) has an angled area (322) that prevents the return of water particles to the blower (300).

23. Blower according to any of claims 15 to 21, wherein the outlet duct (321) of the exhaust (303) has a slope with a downward inclination that prevents the return of water particles to the blower (300).

24. Blower according to the preceding claim, wherein the slope with the downward inclination of the outlet duct (321) is located between the lower end (305) of the blower (300) and the bent area (322).

25. Blower according to any of claims 15 to 24, wherein the water passage (306) has sections (323), and each section (323) has a diameter, the diameter of the sections (323) being reduced between the water inlet (302) and the blowing air passage (304), such that the speed of the water is accelerated as it moves through the sections (323) of the water passage (306) so that the water is introduced in an atomized form into the blowing air passage (304).

26. Blow molding machine according to any one of claims 15 to 25, wherein the blowing air passage (304) has a first tube (324) that directs the blowing air into the interior of the preform and the water passage (306) has a second tube (325) that introduces the liquid water into the first tube (324), the first tube (324) has a first diameter and the second tube (325) has a second diameter, the first diameter of the first tube (324) is larger than the second diameter of the second tube (325), and the first tube (324) and the second tube (325) are coaxial.

27. Blowing machine according to any of claims 15 to 26, wherein the exhaust (303) is connected to the water inlet (302) to reintroduce into the blowing machine (300) hot water recovered from the steam generated when cooling the glass container (1).

28. Glass container forming machine comprising preparation molds (210), each preparation mold (210) having a cavity for receiving a drop of molten glass and obtaining a preform, blow molds (220), each blow mold having a cavity for receiving a preform and obtaining a glass container (1), transfer devices (230) for transferring the preforms from the preparation molds (210) to the blow molds (220), blowing machines (300), according to claims 14 to 25, for introducing air into the preforms and expanding the preforms to obtain the glass containers (1) and for introducing liquid water into the glass containers (1) and cooling the glass containers (1), an air supply (500) for supplying air to the blowing machines (300), and a water supply (400) for supplying liquid water to the blowing machines (300).

29. Machine according to claim 28, wherein the water supply (400) comprises: an industrial water supply source (401), a demineralizer (402) connected to the industrial water supply source (401) to obtain liquid water with a total dissolved solids level in the liquid water equal to or less than 25 ppm, a first water tank (403) connected to the demineralizer (402) to store the liquid water, a pump (404) connected to the first water tank (403) to pressurize the liquid water, a second water tank (405) connected to the outlet of the pump (404) to store the pressurized liquid water, and a heater (406) to heat the pressurized liquid water from the second tank (405) that is supplied to the blowers (300).

30. Machine according to the preceding claim, wherein the water supply (400) additionally comprises a heat exchanger (407) having an inlet connected to the exhausts (303) of the blowers (300), a first outlet connected to the first water tank (403) and a second outlet connected to the outside atmosphere, such that the steam extracted from the exhausts (303) is directed to the heat exchanger (407) where said steam is decomposed into air and hot water that is stored in the first water tank (403).

31. Machine according to any one of claims 28 to 30, wherein for each blower (300) the machine (200) comprises at least a first valve (501) for controlling the passage of blowing air at the blowing air inlet (301), at least a second valve (502) for controlling the passage of water at the water inlet (302), at least a third valve (503) for controlling the passage of steam at the exhaust (303), and at least a fourth valve (504) for controlling the passage of cooling air at the cooling air inlet (307).

32. Machine according to the preceding claim, wherein the third valve (503) is a valve with an electronically controllable opening.

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