Patent Application
20050092755
Embodiments of the present invention relate to a mounting cup, or blind refrigerant cup, for use with a canister containing a refrigerant for use in an automotive air conditioning system. More particularly, certain embodiments of the present invention relate to a refrigerant cup that rises during assembly with a container of refrigerant such that the refrigerant cup impedes the use of a slide-on can tap to be used with the refrigerant cup.
Pressurized liquids and gases, such as refrigerants for example, are often stored and sold in small containers that are sealed with a refrigerant cup. The conventional container is usually shaped like a can with a neck at the top and is provided with an opening at the neck encircled by an annular bead.
The conventional refrigerant cup is formed from coils or sheets of tin plated steel or any number of other metals or alloys. The refrigerant cup includes a cylindrical outer wall extending from a circular base to a peripheral rim and a cylindrical pedestal extending from the base concentrically with the outer wall. The peripheral rim includes a skirt that extends parallel to the outer wall such that the peripheral rim forms an inverted U-shaped or variation cross-section with the outer wall. The refrigerant cup is capable of being crimped or clinched to the annular bead located on the container to establish a seal between the refrigerant cup and the container.
A plastic or rubber sealing material such as a gasket is placed within the peripheral rim of the refrigerant cup between the outer wall and the skirt for insuring the sealing engagement between the peripheral rim of the refrigerant cup and the annular bead of the container. Dimples may be added to the outer wall of the refrigerant cup to retain the gasket within the interior space and/or to aid in the container-filling process.
During the cup forming process, the pedestal may be machined to have threads and thus be configured for connection to a can tap with corresponding threading. After the can tap is screwed onto, and sealed to, the pedestal, the top end of the pedestal is punctured by the can tap to access the contents of the container. A valve assembly housed inside the refrigerant cup may be substituted for the pierced-type arrangement with corresponding changes to the can tap device.
Typically, refrigerant cups are fabricated at a cup assembly plant and shipped to a filling plant where the refrigerant cups are placed in hoppers and eventually fed in an automated process to be sealed to the containers. During a typical under-the-cup assembly process, the container is sometimes partially filled with liquid. The refrigerant cups are then fed to the container by the automated process such that the peripheral rim of the refrigerant cup is placed upon the annular bead of the container with the sealing material disposed therebetween. The container is then positioned below a machine known in the art as a filling head, which lifts the cup off of the container by a vacuum to leave a narrow gap between the container and the cup. The filling head then draws a vacuum within the container through the gap. The filling head then pressurizes the container through the gap. In the case of refrigerant, the filling head adds the refrigerant to an empty, vacuumized container. Some products require oil, sealant, dye, or other additives prior to refrigerant charging. The filling head then deforms or crimps the refrigerant cup with an expanding collet to bring the peripheral rim and gasket of the refrigerant cup into sealing engagement with the annular bead of the container. The displacement of material caused by the crimping process may raise the pedestal up slightly, depending on the thickness and strength of the material.
Once the refrigerant cup is sealed to the container, the container is processed through a hot tank bath which significantly raises the temperatures of the can and its contents. In the case of Refrigerant 134a, the temperature reaches 130 degrees Fahrenheit and the pressure within the container reaches 208 psi. The changes in temperature and pressure within the container cause the contents to expand and push against the refrigerant cup and cause the pedestal to again “rise.”
In the case of certain substitutes for ozone depleting refrigerants such as Refrigerant 12, United States Environmental Protection Agency (EPA) regulations require the refrigerant cup to have certain additional features. The EPA has passed regulations to discourage attempts to mix car air conditioning system refrigerants because many of the available refrigerants react adversely with each other. Therefore, the EPA requires containers of refrigerant to be configured for use only with one specific kind of fitting, which, in turn, may be used only to fill the air conditioning systems of cars that are designed to use the corresponding refrigerant. Specifically, the EPA requires the refrigerant cups on containers of refrigerants to have a specific threading that corresponds to the threading of the specific can tap.
However, certain pre-existing slide-on clamps or fittings are available that may be connected to the refrigerant cup without engaging the specific threading. The clamps have a top surface connected to a continuous flange or series of flanges. The flanges are located a certain distance from the top surface and are used to wrap around the bottom of the refrigerant cup skirt such that the top surface is secured above the refrigerant cup. The clamps may then be connected to a non-regulated can tap that retrieves the contents without having to engage the threading on the refrigerant cup. This type of can tap could then be used to mix refrigerants in car air conditioning systems.
Therefore, the EPA has required that the refrigerant cups have certain features that impede attachment to the slide-on clamps. An example of such a refrigerant cup having a long skirt is shown in
Additionally, for similar reasons, the clamps cannot effectively be connected to a refrigerant cup having a “bumped” pedestal. An example of such a refrigerant cup having a bumped pedestal is shown in
The EPA's requirements for refrigerant cups create certain manufacturing and production problems, however. For example, as shown in
Furthermore, “bumping up” the pedestal to an appropriate height by methods known in the art prior to the assembly of the refrigerant cup to the container causes the pedestal to be caught in the hopper and other assembly transportation means. Thus, the bumped pedestal slows down the automatic feeding process of the refrigerant cups onto the containers. Additionally, the step of bumping up the pedestal may need to be done in a manufacturing step separate from stamping, which slows down production speed.
Therefore, a need exists for an improved refrigerant cup that can meet EPA requirements but at the same time not slow down assembly and production time and also overcome the other deficiencies associated with conventional refrigerant cups.
Certain embodiments of the present invention include a process for forming a metal cup having a pedestal, wherein the cup is mounted to a container carrying pressurized contents and the pedestal is to impede a fitting from being effectively mounted to the cup, in compliance with United States Environmental Protection Agency requirements. The process includes forming a cup, wherein the forming step includes providing the cup with a base from which extends a pedestal and an outer wall having a peripheral rim aligned along a rim plane and from which extends a skirt. The pedestal extends to a first height from the base relative to the rim plane such that the pedestal does not impede the fitting from being mounted to the cup. The process further includes providing a container having an opening, placing the cup upon the container at the opening, filling the container with the contents, and sealing the cup about the container at the opening such that the pedestal rises a first pedestal distance from the base relative to the rim plane from the first height. The process further includes pressurizing the container such that the contents in the container expand and cause the pedestal to rise a second pedestal distance from the base relative to the rim plane such that the pedestal extends beyond the rim plane to a final height, wherein when the pedestal is at the final height, the pedestal impedes the fitting from being effectively mounted to the cup.
Certain embodiments of the present invention include a process for forming a metal cup having a pedestal, wherein the cup is mounted to a container carrying pressurized contents and the pedestal is to impede a fitting from being effectively mounted to the cup, in compliance with United States Environmental Protection Agency requirements. The process further includes forming a cup, wherein the forming step includes providing the cup with a base from which extends a pedestal and an outer wall having a peripheral rim aligned along a rim plane and from which extends a skirt. The skirt includes a bottom end aligned along a skirt plane. The rim plane and the skirt plane are separated by no more than a skirt distance such that the skirt does not impede the fitting from being mounted to the cup. The pedestal has a top end extending from the base to a first height proximate the rim plane such that the pedestal does not impede the fitting from being mounted to the cup. The process further includes feeding the cup from a hopper along an assembly transportation system to be placed on the container, providing a container having an opening, placing the cup upon the container at the opening, drawing a vacuum within the container and filling the container with the contents underneath the skirt, and sealing the cup about the container at the opening such that the pedestal rises a first pedestal distance from the base relative to the rim plane from the first height. The process further includes pressurizing the container such that the contents in the container expand and cause the pedestal to rise a second pedestal distance from the base relative to the rim plane such that the pedestal extends beyond the rim plane to a final height, wherein when the pedestal is at the final height, the distance between the bottom end of the skirt and the top end of the pedestal is such that the cup impedes the fitting from being effectively mounted to the cup.
Certain embodiments of the present invention include a cup for use with a container carrying pressurized contents, wherein, in compliance with United States Environmental Protection Agency requirements, the cup impedes a fitting from being effectively mounted to the cup. The cup includes a base from which extends a pedestal and an outer wall. The outer wall includes a peripheral rim being aligned along a rim plane, and the peripheral rim includes a skirt having a bottom end aligned along a skirt plane. The rim plane and the skirt plane are separated by no more than a skirt distance such that the skirt does not impede the fitting from being mounted to the cup. The pedestal extends to a first height from the base relative to the rim plane such that the pedestal does not impede the fitting from being mounted to the cup. The cup is configured to be sealed upon the container such that the pedestal rises a first pedestal distance from the base relative to the rim plane from the first height. The container sealed with the refrigerant cup is pressurized such that the contents in the container expand and cause the pedestal to rise a second pedestal distance from the base relative to the rim plane such that the pedestal extends beyond the rim plane to a final height, wherein when the pedestal is at the final height, the pedestal impedes the fitting from being effectively mounted to the cup.
The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, certain embodiments. It should be understood, however, that the present invention is not limited to the arrangements and instrumentalities shown in the attached drawings.
The refrigerant cup 10 has a substantially flat base 14 disposed in a central area 18 with a peripheral rim 22 being integrally connected to the base 14 by an outer wall 26. The peripheral rim 22 includes a skirt 34 that extends outward from the outer wall 26 and that is formed integrally therewith. The skirt 34 curves away from the outer wall 26 and extends to a lower skirt plane 56. The skirt 34 is concentric with the outer wall 26 to define a gap 28. A gasket 25a is retained within the gap 28 between the skirt 34 and the outer wall 26a. The top of the peripheral rim 22 is positioned along a horizontal plane 54. The skirt 34 extends to the lower skirt plane 56, which is located, by way of example only, a distance of 0.115 inches from the horizontal plane 54. By way of example only, the distance between the lower skirt plane 56 and the horizontal plane 54 does not exceed 0.135 inches.
The refrigerant cup 10 further includes a cylindrical pedestal 38 formed in the central area 18. The pedestal 38 is formed by side walls 42, a top wall 58, and a curved top rim 62 that define an interior cavity 46 of the pedestal 38. The top wall 58 and top rim 62 that are generally positioned along the horizontal plane 54. Alternatively, the top rim 62 of the pedestal 38 may extend slightly beyond the horizontal plane 54, for example, by no more than 0.015 inches, or may be positioned slightly below the horizontal plane 54, for example, by 0.005 inches.
During the forming process, the pedestal 38 is machined to form threads 50 along the side walls 42 such that the pedestal 38 may be connected, i.e., screwed, to a can tap (not shown) which punctures the top wall 58 or opens an included valve to dispense the contents. Depending on the contents that the refrigerant cup 10 will be used to seal, the EPA requires specific threading patterns to be used on a refrigerant cup pedestal, and the threading patterns are to correspond only to a particular can tap. The can tap in turn may only be used in certain air conditioning systems that are prepared or manufactured for the contents of the particular container. In the case of Refrigerant 134a, specific threadings are required for use with only a particular can tap that can be used to fill car air conditioner systems that use Refrigerant 134a.
Alternatively, or additionally, the refrigerant cup 10 may be coated with an epoxy or other surface coatings on the top surface.
Once the refrigerant cup 10 is stamped and threaded, it may be transported for assembly with a container. Because the pedestal 38 does not extend very far beyond the horizontal plane 54 of the peripheral rim 22, if at all, the pedestal 38 does not cause the refrigerant cup 10 to be caught in hoppers or other carrying and transportation devices used in the assembly process. Thus, the reduced height of the pedestal 38 allows for easier and more efficient feeding of the refrigerant cup 10 through the hopper or any other assembly transportation system.
The container 66 may or may not be empty prior to the refrigerant cup 10 being placed thereon, depending on what product is to be carried within the container 66. If refrigerant, for example, Refrigerant 134a is the product, the container 66 is empty when the refrigerant cup 10 is added. If an additive product is to be carried in the container 66, then the additive is put in the container 66 prior to the refrigerant cup 10 being added.
Returning to
Furthermore, as the outer wall 26 is deformed just under the annular bead 78, the length of the outer wall 26 is reduced such that the thin, malleable metal is displaced toward the central area 18 of the refrigerant cup 10. The displacement of the material to the central area 18 causes the pedestal 38 to “rise up” in the direction of arrow C such that the top rim 62 of the pedestal 38 extends further above the horizontal plane 54. By way of example only, the pedestal 38 may rise a distance within the range of 0.025 inches to 0.050 inches. The distance the pedestal 38 rises depends on the thinness, hardness, shape, and ductility of the material and the type of the material. Depending on the desired rise of the pedestal 38, different materials of different thicknesses may be used.
The pressure in the container 66 also rises as the temperature rises. For example, the pressure within the container 66 rises to approximately 208 psi at 130 degrees Fahrenheit. The arrows D indicate the pressure within the container 66 pushing outward against the walls of the container 66 and the refrigerant cup 10. Because the refrigerant cup 10 is made of an appropriate material at an appropriate thinness and shape (in the case of refrigerant 134a, the thinness and material is, by way of example, 0.009 to 0.013 inches thick T-2 electrolytic tin plate), the pressure pushes the pedestal 38 further upward in the direction of arrow C such that the top rim 62 rises to a desirable height. By way of example only, the pedestal 38 may rise upward a distance within the range of 0.070 inches to 0.105 inches. By way of example only, the desirable height may be at least in a range of 0.120 to 0.140 inches above the horizontal plane 54. Alternatively, the pedestal 38 may be configured to rise to any number of other desirable heights above the horizontal plane 54. Furthermore, where different pedestal heights are required for different products to provide a suitable impediment to the use of slide-on fittings, the type, thickness, and hardness of the material may be altered in conjunction with the properties of the product such that the pedestal 38 rises to the required height.
The container 66 is then removed from the hot water bath and is dried and packaged for shipping. The pedestal 38 remains in its “risen” position after removal from the hot water bath. In operation, a can tap is screwed onto the pedestal 38 to dispense the contents of the container into an appropriate air conditioning system. For example, in the case of Refrigerant 134a, the EPA requires the pedestal 38 to have a particular thread pattern that corresponds to a can tap for use only with cars that use Refrigerant 134a and have a special 134a fitting.
Therefore, the EPA requires that refrigerant cups used with any regulated refrigerants not only have a specific threading for use with a specific can tap, but also be structured to impede use with a slide-on clamp 86. The EPA requires that a refrigerant cup have either a long skirt, i.e., a skirt sufficient to impede the flanges of the slide-on clamp, or a raised pedestal, i.e., a pedestal sufficient to impede the flanges of the slide-on clamp. By extending the skirt or the pedestal, the clamp 86 cannot be positioned about the refrigerant cup because the legs 102 are not long enough for the flanges 106 to reach under the skirt. The refrigerant cup 10 of
The material, thickness, temperatures, and pressures disclosed above are all examples of possible parameters for use in meeting pedestal height requirements for cans of Refrigerant 134a. In alternative embodiments, different parameters may be more appropriate for different canned refrigerants. For example, a thicker metal may be used where the pedestal does not need to be as high as it does for certain cans of refrigerant. Also, different pedestal diameters may be required with different refrigerants that require a pedestal having a different height. Different pedestal diameters require different heights to impede slide-on clamps. Additionally, different products may generate different pressures within the container during the hot water bath such that thicker or thinner materials or different cup shapes may be needed to achieve the desired amount of pedestal rise for that particular product. The material of the refrigerant cup, the thickness of the material, the hardness and ductility of the material, the product in the container, and the required pedestal height are all factors that are to be considered in relation to each other in practicing the embodiments of the invention.
The refrigerant cup of the various embodiments provides several benefits. First, the refrigerant cup is made with a short skirt, that is to say, the skirt does not extend from the horizontal plane to the lower skirt plane such a distance as to prevent a slide-on clamp from engaging the refrigerant cup. Thus, the short skirt does not interfere with the vacuum process or the filling process for the container as a longer skirt does. Therefore, the short skirt allows for faster and more efficient assembly and manufacturing time.
Furthermore, the process of assembling the refrigerant cup and the container is used to raise the pedestal to a desired height without having to deliver the refrigerant cup for assembly with the pedestal already at the desired raised or bumped height. By forming the refrigerant cup from an appropriate material at an appropriate thickness, the refrigerant cup uses the characteristics of the assembly process itself to “bump” or “raise” the pedestal during production such that the pedestal does not need to be bumped prior to production. The refrigerant cup is formed with the pedestal at a reduced height proximate the horizontal plane of the peripheral rim. Therefore, the refrigerant cup can be easily transported during the manufacturing and assembly process without the pedestal be caught or snagged on equipment along the way. Once the refrigerant cup is placed on the container, the thinness, shape, and ductility of the refrigerant cup allow for it to be substantially raised a first time during the crimping process. Then, later, the thinness, shape, and ductility of the refrigerant cup allow for it to be substantially raised again by the pressure formed within the container during the hot water bath step. The material and its thickness are determined such that the pressure in the can for a particular product causes the pedestal to raise to a desired height above the horizontal plane of the peripheral rim. Thus, the refrigerant cup of the different embodiments avoids production problems associated with a raised pedestal while at the same time accommodates the slide-on fitting obstruction requirements of the EPA for certain products.
While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
This application is related to, and claims priority from, Provisional Application No. 60/516,776, filed Nov. 3, 2003, titled “Refrigerant Cup For Use With A Container,” the complete subject matter of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60516776 | Nov 2003 | US |
