KR102691763B1 - Method for assembling a dispensing system for dispensing a fluid medium - Google Patents

Abstract

The invention provides a method of assembling an injection system (1) for spraying a pressurized stored fluid medium, comprising the steps of providing a valve cup (10) comprising a valve (50) and a bag (100) - The valve (50) is configured to be attached to an opening of the bag (100), and the valve cup (10) is formed of a first plastic or includes a lining (70) formed of the first plastic. inserting the valve (50) into an opening of the bag (100) and fluidly sealing the bag (100) to the valve (50); providing a container (30), the container (30) comprising an opening (32) suitable for storing a fluid medium under pressure and formed at least in part from a second plastic; Inserting the bag (100) into the container (30) and positioning the valve cup (10) in the opening (32) of the container (30); Pressurizing the internal space of the container 30; and welding the valve cup (10) to the container (30) to provide a seal between the valve cup (10) and the opening (32) of the container (30).

Description

{METHOD FOR ASSEMBLING A DISPENSING SYSTEM FOR DISPENSING A FLUID MEDIUM}

The present invention relates to a method of assembling a dispensing system for dispensing a pressurized stored fluid medium, the dispensing system exhibiting improved sealing performance and adhesion between a valve cup and a container.

Systems for spraying fluid media stored under pressure are generally well known. Many systems spray aerosols, such as deodorants or paints, typically as a fine spray. However, any fluid medium, such as shampoo, etc. may be stored and dispensed.

A typical system includes a vessel, a valve, and a valve cup, with the valve cup typically supporting the valve in its central portion and closing the opening of the vessel. The interior space of the vessel is usually kept pressurized by the valve and seals between the valve cup and the valve, and between the valve cup and the vessel opening. When the valve is actuated, the pressure difference between the interior space of the vessel and the external environment forces the fluid medium out of the vessel. Some systems use a two-stage vessel with an inner and outer vessel, one of which contains the propellant gas, while the other may use a single vessel with a fluid medium that also acts as the propellant.

Traditionally, containers are made of metal, usually aluminum. Recently, there has been an increasing tendency to use plastics, namely polyethylene terephthalate (PET), as containers for these injection systems for various advantages such as cost and ease of manufacture. The system must be stable and capable of withstanding the internal pressure of the vessel while providing adequate sealing.

Conventional systems using PET containers also typically use metal, such as aluminum, for the valve cup, which ensures a proper sealing fit between the valve cup and the valve. The valve cup may be secured to the lip of the opening of the container. Although the adhesion between the valve cup and the container is often sufficient at most normal operating temperatures, high temperatures can cause PET containers to deform significantly so that the connection between the aluminum valve cup and the container opening is no longer fluid tight. This is very disadvantageous because the propellant gas and/or fluid medium may escape from the vessel.

DE 37 37 265 A1 proposes a solution to this problem by additionally forming the valve cup from a plastic such as PET. In this case, since the valve cup and the container are made of the same or similar materials, the valve cup can be welded, for example friction welded, to the container. At high temperatures, welding is sufficient to maintain a seal between the valve cup and vessel.

European safety requirements specify that aerosol systems should not be exposed to temperatures above 50°C. However, in practice, these injection systems can be exposed to much higher temperatures. In the case of DE 37 37 265 A1, the disclosed device does not provide sufficient sealing performance at temperatures exceeding 50° C., as the plastic valve cup can also deform at these temperatures to the extent that the seal between the valve cup and the valve is lost. Because there is.

There is a need for a method of assembling a spraying system that sprays a fluid medium and exhibits sufficient sealing performance at temperatures higher than 50°C. Here, temperatures above 50°C should be understood as reasonable temperatures to which the injection system may be exposed, for example up to 100°C.

The above problem is solved by a method of assembling an injection system for spraying a stored fluid medium under pressure, the method comprising:

- providing a valve cup comprising a valve and a bag, wherein the valve is configured to be attached to an opening of the bag, the valve cup being formed of a first plastic or comprising a lining formed of the first plastic. providing a;

- inserting the valve into the opening of the bag and fluid-tight sealing the bag to the valve;

- providing a container, said container comprising an opening and suitable for storing a fluid medium under pressure, the container being formed at least in part from a second plastic;

- inserting the bag into the container and positioning the valve cup in the opening of the container;

- pressurizing the internal space of the vessel; and

- welding the valve cup to the vessel to provide a seal between the valve cup and the opening of the vessel.

In this method, the bag is attached to the valve forming part of the valve cup. The valve cup and bag are then inserted into the container and positioned adjacent to the opening of the container. In this state, the internal space of the vessel can be pressurized using propellant gas, preferably by undercup gassing. That is, the space between the bag and the container can be pressurized. Assembling the injection system in this manner allows a pressurized container to be attached to the valve cup ready to receive the fluid medium. Typically the pressure may be lower than that used in conventional vessels.

Because the valve cup and container are formed of plastic, plastic welding can be used to join the two, thereby providing a seal between the valve cup and container. This seal is particularly advantageous when exposure to temperatures above 50° C. causes deformation of the valve cup and/or vessel as the weld and thus seal are maintained.

In another embodiment of the method, the valve cup is formed from a first plastic material, wherein the first plastic material is a semi-crystalline polyester.

A valve cup is a component positioned to support a valve and cover an opening in a container suitable for receiving the fluid medium to be dispensed. Semi-crystalline polyesters have a greater degree of crystallinity than the more amorphous polyesters. As a result, semi-crystalline polyesters typically do not deform when exposed to temperatures above 50° C., at least when compared to amorphous polyesters. In this way, the structural rigidity of the valve cup can be improved at high temperatures, meaning that the seal between the valve and the valve cup maintained by the valve cup is maintained.

A further embodiment of any of the above methods includes a first plastic material having a crystallinity of at least 35%, preferably at least 38%, as measured using differential scanning calorimetry (DSC).

Crystallinity is one property that provides plastic materials with rigidity at high temperatures. Typically, plastics may have some percentage of amorphous regions and some percentage of crystallized regions. When exposed to high temperatures, the amorphous region undergoes a transition from a hard and brittle state to a more rubbery and soft state. Therefore, it can be considered that the amorphous region causes deformation of the plastic at higher temperatures. Providing a material with a high degree of crystallinity can reduce the degree of deformation of plastic materials at high temperatures.

Additionally, crystallinity is usually measured by a specific method - here presented as differential scanning calorimetry. In general, because crystallinity is essentially an average value, different methods may give slightly different results. When using other methods, appropriate scaling should be considered with respect to the values obtained by DSC.

In another embodiment of any of the above methods, the first plastic material is selected from the group consisting of crystallized PET, PBT, PEN, PEN/PET copolymer, or mixtures thereof; The second plastic material is polyester, preferably PET.

Crystallized PET (CPET), PBT, PEN and PEN/PET copolymers may or may be semi-crystalline polyesters. These materials are particularly advantageous for their stiffness at high temperatures as well as other properties in packaging. However, any polyester that can be semi-crystalline and does not deform to a reasonable degree at high temperatures can also be used as the semi-crystalline material. Moreover, any mixture of CPET, PBT, PEN and PEN/PET can be used as the first plastic material. In a preferred embodiment, PBT is used as the first plastic material.

Forming the container from a second plastic such as PET can be very beneficial. In this way, the container can retain the advantages of PET used in packaging, while at the same time being bonded/welded to a valve cup formed from the first plastic. This means that the seal between the valve cup and the container can be maintained even if the container is deformed.

In one embodiment of the method, the container is formed entirely from a second plastic material. Forming the container in this way means that the container retains the beneficial properties of the second plastic. Polyester, especially PET, has many advantages in the packaging field. They are easy to handle and therefore the formation of valve cups and vessels is relatively easy and fast. In some cases, polyester can also be relatively inexpensive. Some polyester can also be recycled, reducing overall overhead costs. Finally, some polyesters can also be sterilized, which is particularly advantageous for medical applications.

In another alternative embodiment of the method, the second plastic material is semi-crystalline polyester.

As an alternative to the above method, at least a portion of the vessel may be formed from a semi-crystalline material. Preferably, this portion is adjacent to or contacts the opening of the container. This portion may be the lip portion, neck portion and/or the entire container. In this way, when the container experiences elevated temperatures, the portion adjacent to or in contact with the opening is not deformed. In other words, at elevated temperatures, the opening maintains its shape. In this way, any seal with the valve cup can be maintained.

Another embodiment of the method provides a container made of a second plastic material having a crystallinity of at least 35%, preferably at least 38%, as measured using a differential scanning calorimeter.

Another embodiment of the method has a second plastic material selected from the group consisting of crystallized PET, PBT, PEN, PEN/PET copolymer, or mixtures thereof, and the first plastic material is polyester, preferably PET. . Preferably, the second plastic material is PBT.

As above, reliable sealing can be achieved by ensuring that the container is stably sealed to the valve cup. Plastic valve cups can be advantageous for a variety of reasons, such as cost and ease of manufacture. However, some plastic valve cups are prone to deformation at high temperatures. The use of plastic valve cups allows welding to plastic containers. Accordingly, even if the valve cup is deformed, the container is secured to the valve cup in such a way that the seal therebetween is not broken. That is, the seal between the valve cup and the container is maintained.

In some configurations, the rigid portion of the vessel may provide a sufficiently rigid basis for any deformation of the valve cup directed radially toward the valve supported by the valve cup. That is, radial forces acting on the rigid portion of the container may cause a compressive force on a portion of the valve at the center of the valve cup. This means that the valve can be reliably held and sealed by the valve cup even if the valve cup is formed of deformable plastic.

In an alternative embodiment of the method, the valve cup is formed of metal or a rigid material, the valve cup includes a polyester lining provided on at least a portion of the valve cup that faces the container when assembled, and the polyester lining is provided on the valve cup. It is held by or coated on the valve cup.

In an alternative valve cup, the valve cup may be formed from two materials; Metal or rigid body, and polyester lining. The metal or rigid material may be formed of any suitable material that will not deform or bend at temperatures above 50°C. That is, the rigidity of the valve cup is provided by metal or a rigid material, which thus ensures that the valve is reliably held and sealed by the valve cup. The polyester lining preferably covers at least a portion of the valve cup of metal or rigid material. Preferably, this portion faces the container when the valve cup is secured to the container. In this way, the valve cup can be welded to the plastic container, thus enabling a seal between the valve cup and the container.

The polyester lining may be coated or retained by the valve cup and secured to the valve cup with adhesive. The polyester lining can be coated directly on the surface of the valve cup, providing a chemical bond between the metal or rigid material and the polyester lining. This can be advantageous if distortion occurs when the polyester lining is heated. Alternatively, the polyester lining may be retained by a specific configuration of the valve cup, for example the valve cup may be shaped to enable crimping or clinching of the polyester lining. This provides a mechanical configuration that can be advantageous when coating is not possible due to the selected material or when the chemical bond is not sufficiently resistant to deformation of the polyester lining. A polyester lining may be provided on the lower surface of the valve cup. The polyester lining may also be formed from any semi-crystalline polyester.

In another embodiment of the method, welding the valve cup to the vessel includes welding the valve cup to the vessel by one of friction welding, ultrasonic welding, and laser welding.

This welding technique can be used to weld plastic to plastic and is particularly advantageous because it prevents the propellant gases from reacting adversely. For example, these technologies do not provide an ignition source.

Any other embodiment of the method includes pressurizing the space of the container between the interior of the container and the exterior of the bag to 1 to 3 bar, preferably 1.5 to 2.5 bar, by gassing the undercup.

Although the pressure of 1 to 3 bar is not particularly high, the pressurization is carried out without any fluid medium to be sprayed being placed within the bag. In this way, when the injection system is welded and sealed, adding any fluid medium to the injection system through its valve increases the pressure within the vessel. This can provide the pressure needed to spray the fluid medium. Performing pressurization in this way significantly facilitates the welding process because the pressures involved are lower.

Another embodiment of any of the above methods includes a vessel comprising a lip and a valve cup including an inverted-U shaped receptacle, wherein prior to welding the valve cup to the vessel, the method includes: It further includes the step of snap fitting to the lip portion.

The inverted-U shaped receiving portion may be provided on the outer surface or diameter of the valve cup and is preferably shaped and sized to receive the lip of the container. In this way, the valve cup can be reliably positioned relative to the container and securely attached, for example by welding. The inverted-U shaped receptacle has at least one protrusion to help secure the valve cup to the vessel, at least temporarily, thereby facilitating welding without consideration of displacement of the valve cup.

Another embodiment of the method further includes folding the bag before inserting the bag into the container such that the footprint of the bag is smaller than the diameter of the opening of the container. Preferably, folding involves twisting the bag about the central axis of the valve or folding the bag in a concertina pattern.

Figure 1 shows an assembled injection system that can be assembled in accordance with the present invention.
Figure 2a shows a cross-section of the valve cup of Figure 1;
Figure 2b shows a top view of the valve cup of Figure 2a.
Figure 3 shows an exploded view of the valve cup and container of Figure 1;
4 shows an exemplary valve cup.
Figure 5 shows a method of assembling an injection system according to the invention.

First embodiment

Figure 1 shows the injection system 1. The injection system 1 comprises a valve cup 10, a container 30 and a valve 50 according to a first embodiment that can be used with the method according to the invention. Typically, vessel 30 is pressurized to a pressure greater than atmospheric pressure. When the fluid medium is stored in the vessel, this pressure may be 7 bar, but the pressure is not limited to this and can take on any desired value, limited only by local or government regulations. Valve 50 is generally held in a fixed position by valve cup 10 such that valve 50 can be actuated into an open position when force is applied to valve 50 by a user. In this position, the pressure difference causes the fluid medium to be ejected from the vessel 30 through the valve 50.

Although valve 50 is shown in detail in FIG. 1, it should be understood that any suitable known valve may replace valve 50. 1, valve 50 may include a body 52, which is preferably cylindrical and includes an interior cavity. Additionally, a plunger 53 is provided and communicates with the internal hollow portion of the main body 52. In some embodiments, plunger 53 may be disposed entirely within body 52, but preferably has a spray tip 54 that protrudes away from body 52.

The spray tip 54 may have any cross-sectional shape, but is preferably cylindrical. Additionally, the spray tip 54 may include an upper channel 55 that forms an internal hollow portion of the spray tip 54. A through hole 56 may be provided at the bottom of the spray tip 54. In Figure 1, through hole 56 extends perpendicular to the axis of upper channel 55, but through hole 56 is not limited to this configuration. Body 52 of valve 50 may also include a lower channel 57 extending from the bottom of body 52 . In one configuration, as shown in Figure 1, the upper and lower channels 55, 57 and the plunger 53 and body 52 share the same common central axis.

The plunger 53 may be provided to slide in the direction of a common central axis. The plunger 53 may be urged to the closed position by a spring (not shown) disposed in the hollow portion of the body 52 and communicating with a receiving portion, such as a vertical flange, of the plunger 53. Figure 1 shows a possible closed position, in which the lower channel 57 is prevented from fluidly communicating with the upper channel 55 and through hole 56 by a seal member 60, which is described in more detail below. To actuate the valve 50, the user may apply a downward force in the axial direction of the body 52, which moves the plunger 53 downward (relative to FIG. 1) so that the through hole 56 is in the body 56. It communicates with the hollow part of (52). In this way, the upper and lower channels 55, 57 can be in fluid communication in this open position. Based on the pressure difference, the fluid medium can be discharged from the vessel 30 through the lower channel 57, the hollow part of the body 52, the through hole 56, and finally the upper channel 55. A cap or other directional device may be provided in communication with the spray tip 54 to direct the flow of fluid medium as it exits the upper channel 55, as is known in the art.

Optionally, bag 100 (see FIG. 5) may be attached to valve 50. Valve 50 may have a recess 58 or any other means for attaching bag 100 to valve 50 . Preferably, bag 100 has an opening that fits around lower channel 57 of valve 50. In this way, the interior space of the bag 100 can be in fluid communication with the lower channel 57 and therefore the upper channel 55 when the valve 50 is actuated. In this preferred configuration, a fluid medium may be contained within bag 100 and the interior space of vessel 30 between the walls of vessel 30 and bag 100 may be pressurized with a propellant gas. Alternatively, the fluid medium may act as a propellant gas in the absence of bag 100.

The valve 50 is supported by a valve cup 10. In the example of Figure 1, valve 50 is centrally mounted in valve cup 10; That is, the valve cup 10 and the valve 50 share the same central axis. The valve cup 10 may have a central opening 11 for this purpose, as shown in Figure 2a. However, it should be understood that any mounting configuration of valve 50 may be used.

2A and 2B further highlight an exemplary mounting configuration for mounting valve 50 to valve cup 10. The central opening 11 may be formed by an inclined portion 13 of the valve cup 10 . The slope 13 defines a diameter d1 at its thickest point and can be inclined towards the central opening 11, which has a diameter smaller than d1. The diameter d1 is preferably larger than the diameter of the main body 52 of the valve 50. In one configuration example, diameter d1 may be 14 mm, but diameter d1 is not limited to this value. Additionally, the inclined portion 13 need not be inclined, but must at least protrude toward the central opening 11. The inclined portion 13 may be provided with a plurality of first internal protrusions 12 on the side facing the central opening 11 . Figure 2b shows eight first internal projections 12, but the invention is not limited to this number. These first inner protrusions 12 may communicate with the outer diameter of the spray tip 54 of the valve 50 to firmly support the spray tip 54 as shown in FIG. 1 .

The valve body 52 may be supported by second internal protrusions 14 arranged below the slope 13 in FIG. 2A . In this manner, the valve 50 closes the valve until the top of the body 52 contacts either the lower surface of the ramp 13 or the seal member 60 located on the lower surface of the ramp 13. The cup 10 may be threaded through the valve cup 10 from its lower surface (ie, starting from the direction in which the container 30 is located in FIG. 1 ). As shown in FIG. 1 , protrusions on the top of body 52 may also be provided to receive seal member 60 . Grooves 59 in the top of the valve body 52 may also be provided to aid alignment of the seal member 60, allow the seal member 60 to flex, and/or equalize pressure.

The seal member 60 is preferably sized to surround the outer diameter of the spray tip 54 and cover the through hole 56 in the closed position, as shown in FIG. 1 . When the plunger 53 is pressed down by the user, the seal member 60 may be bent by the groove 59, although this is not required.

When assembling the valve 50 and valve cup 10, the seal member 60 may be inserted into the lower region of the valve cup 10 defined by the second internal protrusions 14, or the seal member 60 ) may be located at the top of the valve body 52. In any case, when the valve 50 is threaded into the valve cup 10 such that the spray tip 54 passes through the central opening 11, the second internal protrusions 14 hold the valve body 52 in place. It can be maintained. In some embodiments, the second internal protrusions 14 may include ridges 15 that snap fit into corresponding receptacles provided in the valve body 52 . Figure 1 illustrates this configuration in more detail. This configuration allows the valve 50 to be firmly held and sealed by the valve cup 10.

The structure of the valve cup 10 is not particularly limited. 1, 2A and 2B illustrate one example configuration, but the specific configuration is not limited to that shown. The valve cup 10 may include an inverted U-shaped receiving portion 16 that receives the lip portion 38 of the container 30. The outer portion of the inverted-U shaped receptacle 16 may define the outer dimension of the valve or the diameter d2 of the cup 10. Preferably, the diameter d2 is larger than the outer diameter of the opening 32 of the container 30. In one configuration, diameter d2 may be 34.1 mm, but diameter d2 is not limited to this value.

The inverted-U-shaped receiving portion 16 allows the inner surface of the inverted-U-shaped receiving portion 16 to contact the lip portion 38 of the container 30 when the valve cup 10 is attached to the container 30. A space can be formed. The innermost surface of the inner surface may define a diameter d3 of the valve cup 10, which may be equal to or smaller than the inner diameter of the opening 32. In one configuration, diameter d3 may be 24.8 mm, but diameter d3 is not limited to this value. In some configurations, the outermost side of the inner surface may have a protrusion 17 extending toward the innermost side. As shown in FIG. 1 , protrusion 17 may mate with the lower portion of lip portion 38 . Preferably, the protrusion 17 facilitates snap fitting coupling of the valve cup 10 and the container 30, thereby improving the ease of welding process between the valve cup 10 and the container 30 by ensuring accurate alignment. You can do it.

The inverted-U-shaped receiving portion 16 may have a height h1 greater than the height of the lip portion 38 such that the lip portion 38 is completely contained within the inverted-U-shaped receiving portion 16 . In one configuration example, height h1 may be 6.7 mm, but height h1 is not limited to this value. The valve cup 10 may also have a section connecting the outer part of the slope 13 to the inner part of the inverted-U shaped receptacle 16 . This section may define a second height h2 greater than the height h1 such that the section is positioned below the lip 38. In one configuration example, height h2 may be 9.25 mm, but height h2 is not limited to this value.

Additionally, the section may be provided with a number of reinforcement members or reinforcement portions 18 extending from the inverted U-shaped receiving portion 16 to the outside of the inclined portion 13 . This can help increase the structural rigidity of the valve cup 10, and can also reduce production costs and material consumption. Figure 2b shows eight reinforcement sections 18, but the number is not limited to this, and more or less reinforcement sections 18 may be used depending on the desired structural requirements. The reinforcement portions 18 may be made of the same material as the valve cup 10 or a different material. The reinforcement portions 18 may be formed integrally with the valve cup 10 or may be formed as separate components.

As described above, valve cup 10 is configured to be attached to container 30. In Figure 3, container 30 includes an opening 32 that is circular. However, any shaped opening 32 may be used. The container 30 may include a body 34 connected to the opening 32 . In some preferred configurations, container 30 may include a neck 36 connecting opening 32 to body 34. The lip portion 38 may be formed as part of the neck portion 36 or as a separate component. The general dimensions of the vessel 30 are not limited in any particular way apart from their relationship to the dimensions of the valve cup 10 as described above.

According to the invention, the valve cup 10 can be formed from a plastic material, which is semi-crystalline polyester. In this way, the structural rigidity of the valve cup 10 can be ensured beyond the recommended 50° C. due to the higher degree of crystallinity. In some cases, the crystallinity may be greater than 35%, preferably greater than 38%, as measured using differential scanning calorimetry. DSC is a stable method for measuring the thermal properties of materials and will not be described further here.

One material that can be used in the valve cup 10 of the present invention is crystallised PET (CPET). PET can be amorphous or semi-crystalline depending on how it is processed. Typically, PET can be injection molded using a suitable mold (e.g., valve cup). If standard cycle times are used, the resulting PET product is completely amorphous. Semi-crystalline plastics exhibit amorphous regions as well as crystalline structures. When heated, the amorphous region can transition from a hard, brittle state to a rubbery, soft, elastic state; The temperature at which this occurs is known as the glass transition temperature. In semi-crystalline plastics, the stiffness of the plastic is proportional to its degree of crystallinity, which essentially defines the proportion of the plastic that exhibits a crystalline structure. Because the crystalline structure does not transition from a hard to a rubbery state, the crystalline structure maintains its shape and can therefore maintain the rigidity of the semi-crystalline plastic even when the amorphous region transitions at the glass transition temperature.

The approximate crystallinity of PET is 30% to 40%, but other percentages may be possible. CPET can be formed by heating virgin PET and cooling the heated PET slowly, more slowly than prescribed by the standard cycle used in injection molding, to form a crystalline structure. Therefore, CPET has a high degree of crystallinity. In contrast, amorphous PET (APET) cools much faster, preventing crystalline structures from forming.

CPET can also have nucleating agents added to it to enhance the formation of crystalline structures within the material. Alternatively, other additives, such as glass particles or fibers, may be introduced into PET to increase stiffness and/or durability.

Typically, PET films and bottles have limited crystallinity, with microcrystals typically resulting in clear, transparent materials. This is probably the most common form of PET. CPET requires more careful control during molding and can therefore be much more expensive to produce.

CPET deforms less under stress than amorphous PET (APET), especially at higher temperatures. This is mainly due to the rigidity of its internal crystalline structure. Because semicrystalline polyesters contain both crystalline and amorphous regions, they can be characterized by their glass transition temperature. For PET, the glass transition temperature ranges from 67°C for amorphous PET to 81°C for semi-crystalline PET. Therefore, in the case of PET, a high glass transition temperature (preferably above 74° C.) is correlated with a high degree of crystallinity, and it is therefore preferred that PET with a high glass transition temperature is used as the valve cup 10.

In a preferred embodiment, polybutylene terephthalate (PBT) is used as the plastic material for the valve cup 10. PBT is always semi-crystalline in normal commercial settings. Typically, the degree of crystallinity is always greater than 30%, usually in the range of 40% to 50%. The glass transition temperature is approximately 66°C for PBT, but PBT is generally stiffer than amorphous PET due to its high crystallinity. This makes PBT an excellent material for use as the valve cup 10.

Another suitable material is polyethylene naphthalate (PEN). PEN is very stable, especially at high temperatures. PEN can also form semi-crystalline structures and has a glass transition temperature of about 125°C. Compared to PET, PEN has a higher oxygen and water vapor barrier, tensile strength and flexural modulus. Additionally, the molding and blowing cycle for PEN is much shorter than for PET, increasing productivity. However, the cost of PEN is currently much higher than that of PET.

It should also be understood that many other polyesters may be used as long as they exhibit appropriate semi-crystalline properties. Polyester based can also be used. In one embodiment, a PEN/PET copolymer may be used, with the percentage of PEN being relatively low for cost reasons compared to the percentage of PET, for example 10-20%. Other copolymers may be used, such as PEN/PET copolymers or even PET/PBT/PEN copolymers. However, either PET, PBT or PEN can be mixed with other additives such as other polyesters and/or nucleating agents to form a semi-crystalline structure.

Additionally, if the valve cup 10 is formed from semi-crystalline polyester, the valve cup 10 can be welded to the container 30 when the container is formed from a second plastic material. The welding may be performed using any suitable technique for welding two plastics together, but is preferably one of friction welding, ultrasonic welding or laser welding. In this case, the container 30 can be formed from PET of any suitable crystallinity and then welded to the valve cup 10. This ensures that the valve cup 10 (e.g., inverted-U-shaped receiving portion 16) does not separate from the container 30 (e.g., lip portion 38) even if deformation of the container 30 occurs at high temperatures. ensure that it does not occur.

According to the first valve cup (10) used in the method of the present invention, the use of semi-crystalline polyester as a material for the valve cup (10) does not cause deformation or distortion of the valve cup (10), so it can be used at temperatures above 50°C. It is ensured that the valve 50 is kept stable at temperature by the valve cup 10. Additionally, the use of semi-crystalline polyester as the material of the valve cup 10 means that the container 30 can be welded to the valve cup 10, so that even if deformation of the container 30 occurs, the container 30 The seal between and valve cup 10 is maintained. Accordingly, the advantageous properties of PET when used as container 30 can be maintained without compromising sealing performance at high temperatures.

However, the material of container 30 is not limited to PET and may be any suitable polyester, or may also be formed of the semi-crystalline polyester.

As mentioned above, the rigidity of the valve cup 10 can also be improved by using reinforcement members 18. The reinforcing elements 18 may be formed of the same semi-crystalline polyester or may be formed of different materials, for example metal.

It should be understood that various modifications to the specific structures of valve cup 10, vessel 30, and valve 50 may be made while following the principles of the first embodiment of the present invention.

Second embodiment

As a second example of a component used with the method of the present invention, a portion of the container 30 may be formed from the semi-crystalline polyester used in the valve cup 10 of the first example. In particular, the portion adjacent to or in contact with the opening 32 of the container 30 may preferably be formed of semi-crystalline polyester. In contrast, valve cup 10 may be formed of any polyester, such as PET.

In a second embodiment, the opening 32 of the container 30 is formed of semi-crystalline polyester to maintain rigidity at temperatures exceeding 50°C. The valve cup 10 can maintain a seal against the valve 50 when the valve cup 10 begins to deform at high temperatures due to a compressive force acting radially inward from the opening 32 of the container 30. will be.

Alternatively, the valve cup 10 may be structured in such a way that it induces any deformation in the area away from the valve 50 , ie away from the slope 13 . For example, referring to Figure 2A, the difference in height h1 and h2 is used to channelize any strain to be concentrated in the section connecting the inverted-U shaped receiver 16 and the ramp 13. It can be helpful. Other structural configurations may also be considered. In some cases, reinforcement members 18 may be configured to prevent any deformation of valve cup 10 in a position surrounding valve 50 .

In a second embodiment, the container 30 is preferably formed of semi-crystalline polyester only in the portions adjacent to or in contact with the opening 32. This may include only the lip 38. Alternatively, the entire neck 36 and lip 38 may be made of semi-crystalline polyester. In other configurations, the entire container 30 may be formed from semi-crystalline polyester, although this may increase the cost and/or difficulty of the manufacturing process associated with forming the container 30.

As in the first embodiment, the use of semi-crystalline polyester as a material for at least a portion of the container 30 allows the valve cup 10 to be used because no deformation or distortion of the opening 32 of the container 30 occurs. It is ensured that it is stably maintained by the container 30. This means that any deformation of the valve cup 10 can be limited or properly deflected, so that the valve 50 remains stable. Additionally, using semi-crystalline polyester as the material for the portion proximal to the opening 32 of the vessel 30 means that the polyester valve cup 10 can be welded to the vessel 30 and thus the valve cup 10. ) ensures that the seal between the container 30 and the valve cup 10 is maintained even if deformation occurs. The advantageous properties of using PET when used as valve cup 10 and potentially as part of container 30 can be maintained without compromising sealing performance at high temperatures.

However, the material of the valve cup 10 is not limited to PET, but may be any suitable polyester, and may also be formed of the semi-crystalline polyester.

Third embodiment

As a third example of components used in the assembly method of the present invention, the main material of the valve cup 10 may be metal or other rigid material. Preferably, the main material is aluminum. The structure of the valve cup 10 may be the same as that of the first embodiment.

Figure 4 shows an example of a valve cup 10 according to the third embodiment. In Figure 4, a polyester lining 70 may be provided on the surface of the valve cup 10, preferably on the portion in contact with the container 30. The polyester lining 70 may be formed only in the area in contact with the container 30, for example on the inner surface of the inverted-U shaped receptacle 16, or may be formed entirely on the lower surface of the valve cup 10. can be formed. Additionally, the polyester lining 70 may be coated on the valve cup 10 or may be a separate component that is subsequently attached via an adhesive and/or held by the valve cup 10. In this regard, valve cup 10 may be configured to clamp or retain a portion of polyester lining 70 .

Polyester lining 70 may be formed from any polyester, but is preferably formed from PET. When the valve cup 10 is formed of metal, ie aluminum or another rigid material, the structural rigidity of the valve cup 10 at temperatures higher than 50° C. is ensured by the structural rigidity of the metal or rigid material. In other words, metals or rigid materials do not deform at temperatures above 50°C. This means that the valve cup 10 can reliably hold and seal the valve 50.

Providing a polyester lining 70 on a portion of the valve cup 10 allows the polyester lining 70 to be applied to a polyester-based container 30, such as the container 30 of the first embodiment, as described above. This means that it can be welded using any technique. In this way, the valve cup 10 is connected to the container 30 such that any deformation of the container 30 at temperatures higher than 50° C. will not cause the valve cup 10 and the container 30 to separate, thereby maintaining the seal between them. ) can be reliably attached to.

Accordingly, the advantageous effects described in both the first and second embodiments can be realized by the third embodiment; That is, the seal between the valve 50 and the valve cup 10 and the seal between the valve cup 10 and the container 30 can be maintained at a temperature higher than 50°C.

As shown in Figure 4, the polyester lining 70 may also have projections 77 similar to the projections 17 of the first embodiment. The protrusions 77 can be formed additionally as part of the polyester lining 70, i.e. by varying the thickness of the polyester lining 70, or they can be formed as part of the protrusions 17 when coating the valve cup 10. It can be formed as a natural result of following others.

Polyester lining 70 need not be formed of semi-crystalline polyester as discussed in the first and second embodiments. However, in some cases, to prevent deformation of the polyester lining 70 that could result in separation from the valve cup 10, the polyester lining 70 may be formed of semi-crystalline polyester.

How to assemble the injection system

According to one embodiment of the invention, there is now provided a method of assembling an injection system using a valve cup (10) or vessel (30) as described in any one of the first to third embodiments.

Figure 5 details the assembly method of the injection system 1 according to the invention. Initially, valve 50 is coupled to valve cup 10. Exemplary methods for performing this combination have been described in connection with the first embodiment and will not be repeated here. Essentially any method or combination can be performed depending on the exact construction of valve 50 and valve cup 10.

As shown in Figure 5(a), the first step of the present invention includes coupling the bag 100 to the valve 50. More specifically, the opening of bag 100 may be attached to the bottom of valve 50, e.g., lower channel 57, so as to be in fluid communication with the interior of bag 100 when valve 50 is actuated. . Valve 50 may be provided with any means, such as recesses 58 in Figure 1, to facilitate such engagement. Bag 100 may be secured by any suitable means such as adhesive, welding or clamping. The combination of bag 100 and valve 50 in a fixed arrangement is generally referred to as Bag On Valve (BOV). Bag 100 is preferably liquid, gas or fluid impermeable.

Once bag 100 is securely attached to valve 50, bag 100 can be folded to reduce its footprint. As shown in FIG. 5(b), the bag 100 can be folded so that the footprint is smaller than the diameter of the valve cup 10. Preferably, the footprint is smaller than the diameter of the opening 32 of the vessel 30 into which the valve cup 10 is assembled, so that the BOV can be inserted into the opening 32. In an exemplary method, the BOV is folded so that the footprint has a diameter (d4) of less than 25 mm or 22 mm, but other diameters are possible.

Folding can be performed in any way to reduce the footprint of the BOV and allow insertion into the container 30. In one embodiment, the flat bag 100 is rolled about the axis of the valve 50 and the valve cup 10, such that the bag 100 forms a spiral shape about the axis of the valve 50. In another embodiment, bag 100 may be folded into a concertina. In both cases, the BOV preferably has an appropriate footprint.

Unlike known methods, the BOV cannot be equipped with a receiving sleeve or tape to maintain the BOV in a folded form. According to the present invention, the folded BOV is inserted directly into the container 30 as shown in Figure 5(c). At this stage, the BOV is slid through the opening 32 of the container 30 while remaining folded, thereby improving ease of insertion.

Once partially inserted, the interior region of vessel 30 may be filled with a gas, preferably a propellant gas. Suitable propellant gases are known in the art and are not discussed further here. The method used is preferably undercup gassing, which essentially means that the gas passes under the valve cup 10 and into the area between the bag 100 and the internal space of the vessel 30. In the present invention, the internal space of the vessel 30 may be pressurized to a pressure between 1 and 3 bar, preferably between 1.5 and 2.5 bar.

As shown in Figure 5(d), once gassing is complete, the BOV is inserted into the vessel 30 such that the valve cup 10 contacts the opening 32 of the vessel 30. In a preferred configuration, the valve cup 10 has an inverted-U shaped receiving portion 16 and the container 30 has a lip portion 38. Accordingly, the BOV may be inserted into the container 30 until the lip 38 of the container 30 contacts the inverted-U shaped receptacle 16.

In a more preferred configuration, the inverted-U shaped receiving portion 16 includes projections 17, 77 adapted to engage in a snap fitting manner with the lower portion of the lip portion 38. In this way, when the valve cup 10 is pressed onto the lip of the container 30, the inverted-U shaped receiving portion 16 has protrusions 17, 77 passing through the lip 38 and the protrusions ( When 17, 77 passes through lip 38, they may be slightly deformed to return to their resting state. Securing the valve cup 10 in this manner helps ensure that the welding process is performed with improved accuracy because the valve cup 10 can be reliably aligned with the vessel 30.

As shown in Figure 5(e), welding head 110 may be positioned on valve cup 10 to weld valve cup 10 to vessel 30. As described in the first to third embodiments, the valve cup 30 may be formed at least partially of plastic. This means that welding such as friction welding, ultrasonic welding or laser welding or plastic welding can be performed to weld the valve cup 10 to the container 30. Any of the welding techniques may be used and these techniques are generally known in the art and are therefore not described in further detail here.

Once welding is complete, the injection system 1 is assembled. Additional assembly steps may be possible, such as adding a protective overcap 120 to cover exposed portions of the valve 50, as shown in FIG. 5(f). The assembled dispensing system 1 can then be transported to various consumers and filled with a variety of different products. To fill the injection system 1 , the fluid medium to be injected is passed through the valve 50 , ie through the upper channel 55 , the through hole 56 and the lower channel 57 into the bag 100 . As bag 100 is filled with fluid medium, the pressure within vessel 30 increases. Preferably, the pressure is increased to about 6 to 8 bar, preferably 6.5 to 7.5 bar. This pressure increase assists the injection of the fluid medium when valve 50 is actuated by the user.

It should be noted that any or all steps of the method may be performed in a sealed environment. This can assist in the assembly of the injection system 1 when the pressure is increased.

According to this method, the injection system is assembled by welding the valve cup 10 to the container 30 after experiencing undercup gassing. While conventional methods generally rely on clinching the valve cup to the container, the present assembly method utilizes welding a specially modified valve cup 10 to the container 30. Welding can also be performed at lower pressures and without the presence of a fluid medium to be sprayed. This can ensure more reliable welding and potentially prevent contamination of the fluid medium to be sprayed.

Accordingly, the invention provides a method of assembling an injection system (1) for injecting a fluid medium, the injection system (1) comprising a valve cup (10) or container (30) that is rigidly deformed at a temperature exceeding 50° C. It also allows welding between the valve cup 10 and the container 30. Primarily, this can be achieved by using a semi-crystalline polyester with a high degree of crystallinity, or by using a layer of polyester on the valve cup of a metal or rigid material.

Claims (14)

A method of assembling a spraying system for spraying a pressurized stored fluid medium, comprising:
Providing a valve cup comprising a valve and a bag, the valve being configured to be attached to an opening of the bag, the valve cup being formed of a first plastic or including a lining formed of the first plastic, Inverse-U providing the valve cup including a shaped receptacle;
inserting the valve into the opening of the bag and fluid-tight sealing the bag to the valve;
providing a container, the container comprising an opening with a lip and suitable for storing a fluid medium under pressure, the container being formed at least in part of a second plastic;
Inserting the bag into the container and positioning the valve cup into the opening of the container;
pressurizing the interior space of the container;
Snap fitting the inverted-U shaped receiving portion to the lip portion; and
A method of assembling a dispensing system for dispensing a fluid medium, comprising welding the valve cup to the container to provide a seal between the valve cup and the opening of the container. 2. A method according to claim 1, wherein the valve cup is formed of a first plastic material, the first plastic material being semi-crystalline polyester. 3. Method according to claim 1 or 2, wherein the first plastic material has a crystallinity of at least 35% as measured using differential scanning calorimetry. 2. The method of claim 1, wherein the first plastic material is selected from the group consisting of crystallized PET, PBT, PEN, PEN/PET copolymer, or mixtures thereof; A method of assembling a spraying system for spraying a fluid medium, wherein the second plastic material is polyester. 2. A method according to claim 1, wherein the container is formed entirely from a second plastic material. 2. A method according to claim 1, wherein the second plastic material is semi-crystalline polyester. 2. The method of claim 1, wherein the second plastic material has a crystallinity of at least 35% as measured using differential scanning calorimetry. 2. The method of claim 1, wherein the second plastic material is selected from the group consisting of crystallized PET, PBT, PEN, PEN/PET copolymer, or mixtures thereof; A method of assembling a spraying system for spraying a fluid medium, characterized in that the first plastic material is polyester. 2. The valve of claim 1, wherein the valve cup is formed of a metal or rigid material, the valve cup comprising a polyester lining formed of a first plastic that is polyester, and the polyester lining is positioned on the valve facing the container when assembled. A method of assembling a spraying system for spraying a fluid medium, characterized in that the polyester lining is provided on at least a portion of the cup, wherein the polyester lining is held by or coated on the valve cup. The method of claim 1, wherein welding the valve cup to the container to provide a seal between the valve cup and the opening of the container includes welding the valve cup to the container by any one of friction welding, ultrasonic welding, and laser welding. A method of assembling a spraying system for spraying a fluid medium, comprising the steps of: The method of claim 1, wherein the step of pressurizing the inner space of the container includes pressurizing the space of the container between the inside of the container and the outside of the bag to between 1 and 3 bar by undercup gassing. A method of assembling a spraying system for spraying a fluid medium. delete 2. The method of claim 1, wherein in inserting the bag into the container and positioning the valve cup in the opening of the container, the footprint of the bag is smaller than the diameter of the opening of the container prior to inserting the bag into the container. A method of assembling a dispensing system for dispensing a fluid medium, further comprising folding the bag to reduce . 14. The method of claim 13, wherein folding the bag includes twisting the bag about a central axis of the valve or folding the bag in a concertina (undercup gassing) pattern. Method of assembling an injection system for.

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