Container for a spraying device

Field of the Invention

0001Provided are containers of use for a spraying apparatus. More particularly, containers are provided for use with fluid spraying devices including, for example, spray guns and spray head assemblies as disclosed e.g. in document <patcit id="pcit0001" dnum="US3401842A"><text>US 3,401,842 A</text></patcit> or <patcit id="pcit0002" dnum="US2007158348A1"><text>US 2007/158348 A1</text></patcit>.

Background

0002Handheld spray guns are commonly used in a variety of commercial and industrial applications, including for example automotive refinishing. Such spray guns can be used with any of a number of coating media, including primers, paints, clearcoat, slurries, fine powders, and other fluid media capable of being atomized and directed through a spray nozzle onto a substrate. Applications for spray guns include painting and texturizing architectural surfaces such as walls and ceilings, as well as painting and body repair for marine and automotive exteriors.

0003Spray guns usually have a reusable gun platform connected with a compressed air source and liquid pipeline in communication with a spray nozzle. The air and liquid are generally directed into a flow channel, where the air atomizes the liquid into fine droplets that are propelled out of the nozzle. Some spray gun setups, including some used in automotive and industrial refinishing applications, have fluid reservoirs that use disposable collapsible liners that are received in rigid containers called paint cups. Commonly, these reservoirs also employ disposable lids and a corresponding retaining collar that releasably couples the lid to the rigid container. Advantageously, the liner and lid collectively protect the non-disposable components from becoming exposed to the paint, or other fluid, to be dispensed. After use, the liner and lid can be removed together from the rigid paint cup and discarded. These configurations are used, for example, in the PPS brand Paint Preparation System and HG ACCUSPRAY brand System (3M Company, St. Paul, MN).

Summary

0004The fluid containers used in spray gun systems can vary substantially in volumetric capacity depending on the application at hand. While handheld spray guns typically use fluid containers ranging in size from 6 to 28 fluid ounces, bulk spray applications often involve containers that are considerably larger. Use of a large fluid container can help minimize waste associated with fluid transfer and cleanup procedures for large scale applications.

0005One of the technical problems associated with large volume containers relates to the handling and storage of the container contents. Following a spraying operation, fluid remaining in the container is usually transferred or stored by removing a retaining collar from the rigid outer cup, then lifting out the disposable lid and liner together along with the fluid. The lid and liner themselves are either not attached or attached to each other by a relatively weak interference fit. If the amount of fluid in the container is substantial, then the lid has a tendency to spontaneously detach from the liner and cause spillage of the fluid contents. This problem is exacerbated when dealing with modern, high-solids coating fluids for low volatile organic compound (or "VOC") applications, which can put a significant strain on the coupling between the lid and liner.

0006The problem also extends to storage of the container contents between spraying operations. Even after the lid and liner are removed from the cup, the coupling between these components may not be sufficient to withstand the positive pressure therein, resulting in fluid leakage. Such pressurization can be induced by any of a number of factors. For example, volatility of the fluid contents can lead to an expansion of the gases within the liner/lid, creating positive pressure over time and rupturing the seal between the lid and liner. Nominal increases in temperature can also lead to such positive pressure.

0007The containers and assemblies described herein overcome the foregoing technical difficulties and provide substantial time-savings and other conveniences for the spray gun operator.

0008In one aspect, a fluid container for a spraying apparatus according to claim 1 is disclosed

0009The above summary is not intended to describe each embodiment or every implementation of the fluid containers described herein. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following Detailed Description and Claims along with accompanying figures of the drawings.

Brief Description of the Drawings

0010<ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">FIG. 1</figref> is a perspective view of a spray gun assembly including a fluid container according to one exemplary embodiment, looking toward the front and side surfaces of the assembly.</li><li><figref idref="f0002">FIG. 2A</figref> is a perspective view of the container of <figref idref="f0001">FIG. 1</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0003">FIG. 2B</figref> is an exploded perspective view of the container of <figref idref="f0001">FIGS. 1</figref> and <figref idref="f0002">2A</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0004">FIG. 3</figref> is a perspective view of an alternative embodiment of the container of <figref idref="f0001 f0002 f0003">FIGS. 1-2</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0005">FIG. 4</figref> is a perspective view of a subassembly associated with the container of <figref idref="f0001 f0002 f0003">FIGS. 1-2</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0006">FIG. 5</figref> is a perspective view of a first component of the subassembly of <figref idref="f0005">FIG. 4</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0006">FIG. 6</figref> is a perspective view of a second component of the subassembly of <figref idref="f0005">FIG. 4</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0007">FIG. 7A</figref> is a perspective views of a fluid container subassembly according to another exemplary embodiment, looking toward its top and side surfaces.</li><li><figref idref="f0007">FIG. 7B</figref> is a perspective views of a component of the subassembly of <figref idref="f0007">FIG. 7A</figref>, looking toward its top and side surfaces.</li><li><figref idref="f0008">FIG. 8</figref> is a perspective view of a fluid container subassembly according to another exemplary embodiment, looking toward its top and side surfaces.</li><li><figref idref="f0009">FIGS. 9A and 9B</figref> are fragmentary perspective views of a fluid container subassembly outside the scope of the claims, looking toward its bottom and side surfaces.</li><li><figref idref="f0010">FIG. 10</figref> is a perspective view of a fluid container subassembly according to another exemplary embodiment, looking toward its top and side surfaces.</li></ul>

DEFINITIONS

0011As used herein: <ul id="ul0002" list-style="none" compact="compact"><li>"Latch" refers to a device having parts or surfaces that engage each other to fasten one object to another.</li><li>"Latching member" refers to one component of a latch.</li><li>"Microreplicated surface" refers to a surface having a three dimensional surface pattern made by impressing or casting the surface pattern with a tooled surface having a negative impression of the surface pattern.</li><li>"Pressurized gas" refers to gas under greater than atmospheric pressure.</li></ul>

Detailed Description

0012As used herein, the terms "preferred" and "preferably" refer to embodiments described herein that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

0013As used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a" or "the" component may include one or more of the components and equivalents thereof known to those skilled in the art. Further, the term "and/or" means one or all of the listed elements or a combination of any two or more of the listed elements.

0014It is noted that the term "comprises" and variations thereof do not have a limiting meaning where these terms appear in the accompanying description. Moreover, "a," "an," "the," "at least one," and "one or more" are used interchangeably herein.

0015Relative terms such as left, right, forward, rearward, top, bottom, side, upper, lower, horizontal, vertical, and the like may be used herein and, if so, are from the perspective observed in the particular figure. These terms are used only to simplify the description, however, and not to limit the scope of the invention in any way.

0016Reference throughout this specification to "one embodiment," "certain embodiments," "one or more embodiments" or "an embodiment" means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as "in one or more embodiments," "in certain embodiments," "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily referring to the same embodiment of the invention.

0017A fluid container according to one exemplary embodiment is shown in <figref idref="f0001">FIGS. 1</figref>, <figref idref="f0002">2A</figref>, and <figref idref="f0003">2B</figref> and designated by the numeral 100. The fluid container 100 is a modular component that can be coupled to a suitable spraying apparatus. General characteristics of the spraying apparatus are shown in <figref idref="f0001">FIG. 1</figref>, with further details provided with respect to <figref idref="f0002">FIGS. 2A</figref> and <figref idref="f0003">2B</figref> and subsequent figures.

0018Referring to <figref idref="f0001">FIG. 1</figref>, the fluid container 100 represents one component of a handheld spray gun assembly 50 that also includes a spray gun platform 52 and a nozzle assembly 54. In the embodiment shown, the fluid container 100 is releasably coupled to a fluid adapter 56, which is in turn coupled to the spray gun platform 52. The spray gun platform 52 has an air inlet 58 connected to a source of pressurized gas, typically air, used to atomize the fluid prior to its discharge from the nozzle assembly 54.

0019In some embodiments, the fluid container 100 is operatively coupled to an integrated nozzle assembly that includes a fluid inlet releasably coupled to the fluid container 100. Preferably, the integrated nozzle assembly is disposable, as described in <patcit id="pcit0003" dnum="WO2010085801A"><text>PCT Application No. WO 2010/085801 (Escoto, et al.</text></patcit>). Advantageously, such a configuration directs the fluid through the nozzle assembly while minimizing or avoiding altogether fluid contact with the spray gun platform, thereby reducing the need for the operator to clean the spray gun platform.

0020As shown, the fluid container 100 includes a rigid outer cup 102, a lid 104, and an outer collar 106. In the illustration, the cup 102 has a bottom wall 103 and a cylindrical side wall 105 (symmetrical about longitudinal axis 109) that collectively define an open end 107 (visible in <figref idref="f0003">FIG. 2B</figref>). When the container 100 is assembled, as shown, the lid 104 extends over open end 107 of the cup 102, where the cup 102 and outer collar 106 are releasably coupled to each other in encircling relation, thereby securing both the liner 108 and the lid 104 to the cup 102.

0021In the particular embodiment shown, the cup 102 has a threaded screw-type connection with the outer collar 106, allowing the outer collar 106 to be securely tightened against the cup 102 by clockwise rotation. The lid 104 is disposed between the open end 107 of the cup 102 and the outer collar 106 of the lid 104, allowing a fluid-tight seal to be formed between the lid 104 and a liner 108 (not visible in <figref idref="f0001">FIG. 1</figref>) when the outer collar 106 is tightened. Advantageously, this configuration also provides an air-tight seal between the liner 108 and the cup 102, allowing the liner 108 to be externally pressurized if desired.

0022In some embodiments, the bottom wall of the cup 102 is omitted, with the cup 102 instead having two open ends that are diametrically opposed to each other. Such a configuration could be useful, for example, in cases where the cup 102 is not normally pressurized during a spraying operation.

0023Optionally and as shown, the cup 102 is either transparent or translucent and has horizontal volumetric markings or other visual indicia to assist the operator in measuring the quantities of fluid received in the fluid container 100. If desired, such indicia could be provided on a translucent or transparent indicating sheet that is inserted into the cup 102 along the inner surface of the side wall 105. Alternatively, the indicating sheet could be wrapped around the outer surface of the side wall 105. The cup 102 itself is preferably made from a rigid material, such as a clarified polypropylene, and has a wall thickness sufficient to prevent the cup 102 from changing shape when filled and/or pressurized.

0024The lid 104 includes a fluid outlet 101 adapted for connecting the fluid container 100 to the fluid adapter 56, which is in turn adapted for coupling to a spraying apparatus such as the spray gun platform 52. In high volume applications where large volumes of fluid are involved, the fluid outlet 101 may instead be adapted for releasable connection to a high pressure fluid line.

0025<figref idref="f0002">FIGS. 2A</figref> and <figref idref="f0003">2B</figref> show, more particularly, the fluid container 100 in respective assembled and exploded configurations. <figref idref="f0003">FIG. 2B</figref> reveals, in particular, the arrangement of the outer collar 106, the lid 104, the flexible liner 108, and the cup 102 relative to each other.

0026During storage, the coating fluid is normally contained in the enclosed or semi-enclosed space provided between the lid 104 and the liner 108. Optionally and as shown, the liner 108 has a size and shape generally conforming to the inner surfaces of the bottom wall 103 and side wall 105 of the cup 102. Similar to the cup 102, and as illustrated in <figref idref="f0003">FIG. 2B</figref>, the liner 108 has a bottom wall 110 and a cylindrical side wall 112 defining a fluid-containing portion and presenting an open end through which the contents of the liner 108 are dispensed when operating the spray gun assembly 50.

0027The liner 108 additionally includes a flange 114 that extends outwardly from the side wall 112 along a plane perpendicular to the axis 109. When the container 100 is assembled, the flange 114 of the liner 108 resides between, and flatly engages, both the lid 104 and a terminal edge 116 of the side wall 105 of the cup 102. Particular options and advantages associated with the use of a lined fluid reservoir such as container 100 are described in detail in <patcit id="pcit0004" dnum="WO9832539A"><text>PCT Publication No. WO 98/32539 (Joseph, et al.</text></patcit>).

0028It is to be understood that the shapes and sizes of the foregoing components in the illustrations are merely exemplary and alternative constructions are possible. For example, the cup 102, lid 104, and liner 108 could also have a generally rectangular or elliptical cross-section, so long as the functionality of the container 100 is preserved.

0029As further shown in <figref idref="f0002">FIGS. 2A</figref> and <figref idref="f0003">2B</figref>, the fluid container 100 includes a pair of latches 120 disposed on opposite sides of the fluid outlet 101. In this exemplary embodiment, each latch 120 includes a tab 122 and a protrusion 124 disposed on the flange 114 and lid 104, respectively. Further details concerning the structure and operation of these latches 120 will be provided later with respect to <figref idref="f0005">FIG. 4</figref>.

0030<figref idref="f0004">FIG. 3</figref> shows a variant of the above container embodiment in which both the outer collar 106 and cup 102 are omitted. Instead, a frame member 228 partially surrounds the liner 108 and provides supporting structure that optionally extends along the circumference of the cup 108 along portions of the side wall 105 and/or the bottom wall 110. Instead, the frame member 228 uses a buckle 230 positioned adjacent the lid 104, where the buckle 230 is mutually coupled to sections of the frame member 228 that are spaced apart from each other along the circumference of the liner 108. The buckle 230 toggles between a first position in which the frame member 228 fits loosely over the liner 108, and a second position in which the frame member 228 applies compression to the liner 108. When the buckle 230 is in its second position, the liner 108 is compressed between the frame member 228 and the lid 104, thus forming a fluid-tight seal between these components. The buckle 230 therefore serves a similar function to that of the outer collar 106 by preventing fluid leakage along the seam between the lid 104 and liner 108.

0031In still other embodiments, the container 100 includes only the lid 104 and the liner 108, with both the cup 102 and the frame member 228 omitted. Such a configuration could be advantageously used in cases where there is essentially no pressurization of the fluid needed to transfer the fluid from the container 100 to the atomizer in the nozzle assembly 54.

0032The pair of latches 120 are further described with reference to <figref idref="f0005">FIG. 4</figref>, which shows the latches 120 located at diametrically opposite sides of the lid 104. The latches 120 releasably couple the liner 108 and the lid 104 to each other. Each latch 120 includes a tab 122 that is pivotally coupled to the flange 114 (shown in <figref idref="f0003">FIG. 2B</figref>) of the liner 108 by a respective hinge 121, whereby the tab 122 can pivot about the hinge 121 between a closed position in which the lid 104 and liner 108 are mutually coupled and an open position in which the lid 104 and liner 108 are not mutually coupled.

0033In the closed position shown in <figref idref="f0005">FIG. 4</figref>, the tab 122 protrudes inwardly from its hinge 121 towards the axis 109, extending across an outer perimeter 123 of the lid 104 as viewed from a direction along the axis 109. To release the latch 120, the tab 122 can be pivoted about the hinge 121 to a position where it extends away from the axis 109, in which the tab 122 no longer extends across the outer perimeter 123 of the lid 104. This pivoting motion, in turn, can be achieved by pinching a distal end 122' of the tab 122 between, for example, thumb and forefinger and then pulling back the distal end 122' away from the lid 104 in a peeling motion.

0034In the latch embodiments described herein, the tab 122 provides a first surface that can be brought to bear against a second, opposing surface located on the lid 104. In the example of <figref idref="f0005">FIG. 4</figref>, each of the tabs 122 has a receptacle 127 that engages, in encircling relation, a respective protrusion 124 located on the top surface of the lid 104. Optionally and as shown, each protrusion 124 has a slightly oversized head 125 such that there is an interference fit between each receptacle 127 and its mating protrusion 124 that effectively locks these members together. Advantageously, this interference fit can prevent the tabs 122 from becoming inadvertently detached from the lid 104. Optionally and as shown, the receptacle 127 is an aperture that passes through the tab 122. Alternatively, the receptacle 127 may extend only part way through the tab 122 and include undercut features that engage and retain the oversized head 125 of the protrusion 124 when the latch 120 is in its closed (i.e. latched) position.

0035Preferably, the latching members that comprise the latches 120, particularly the tabs 122, hinges 121, and protrusions 124, have a suitable configuration, size and material strength whereby the liner 108 can be filled to its capacity with a high solids, low VOC fluid and then suspended securely from the lid 104 without risk of detachment and/or leakage. In some embodiments, the liner 108 has a fluid capacity of at least about 830 milliliters (28 fluid ounces), at least about 1180 milliliters (40 fluid ounces), or at least about 1900 milliliters (64 fluid ounces). In some embodiments, the liner 108 has a fluid capacity of at most about 1000 milliliters (34 fluid ounces), at most about 1900 milliliters (64 fluid ounces), or at most about 2400 milliliters (80 fluid ounces).

0036<figref idref="f0006">FIGS. 5 and 6</figref> show the liner 108 and the lid 104, respectively, as individual components to reveal additional details of this exemplary embodiment. For example, the liner 108 has a cylindrical side wall 126, flat bottom wall 128, and open end 130 that generally conform to corresponding inner surfaces of the cup 102 when the container 100 is assembled. With the container 100 assembled, the open end 130 of the liner 108 is generally aligned with the open end 107 of the cup 102.

0037Generally, the liner 108 has relatively thin walls that enable the liner 108 to collapse under positive external pressure and/or negative internal pressure as its fluid contents are withdrawn and dispensed from the spraying apparatus. It is also preferable, however, that the liner 108 has sufficient structural rigidity to stand entirely self-supported on a horizontal surface to allow an operator to pour a fluid into its open end 130 without deforming its shape. Alternatively, the liner 108 could be configured to deform to, for example, increase its fluid capacity for the application at hand.

0038The lid 104 preferably has a configuration that is compatible with that of the liner 108. <figref idref="f0006">FIG. 6</figref> shows an enlarged view of the lid 104, revealing an optional inner collar 132 located on the bottom side of the lid 104. The inner collar 132 extends along the outer perimeter of the lid 104 and includes a raised ridge 134 that extends along the circumference of the inner collar 132. When the lid 104 and the liner 108 are fully secured to each other (as illustrated in <figref idref="f0002">FIG. 2A</figref>), the outer surface of the inner collar 132 contacts the inner surface of the liner 108. In this embodiment, the raised ridge 134 is sized to produce a snug, interference fit along these contact surfaces between the inner collar 132 and the liner 108 when the container 100 is assembled.

0039In some embodiments, the latch 120 includes a camming member that operates to pry the liner 108 and the lid 104 apart from each other as the latch 120 pivots from its closed position to its open position. This can be especially advantageous when there is resistance to separating the lid 104 from the liner 108, as may be the case if there is an interference fit between these components. As another possibility, the tabs 122 can act as an anchor points (that may be pinched between thumb and forefinger, for example) for facilitating release of the lid 108 from the liner 108 when there is a tight engagement between these components. The existence of these anchor points can allow a user to hold the liner 108 during separation of the liner 108 from the lid 104 without deforming the liner 108 and potentially spilling its contents.

0040As shown in subsequent figures, the latches and latching members can implement various types of retaining features. <figref idref="f0007">FIGS. 7A and 7B</figref>, for example, show a container 200 according to an alternative embodiment. Like the container 100, the container 200 has a liner 208, lid 204, and a pair of latches 220 that releasably couple the lid 204 and liner 208 to each other. The container 200 is distinguished from the prior embodiment in that each latch 220 includes opposing surfaces 240, 242 having inverse microreplicated surfaces. These microreplicated surfaces are characterized by three-dimensional features 244, 244', located on a tab 222 and an opposing surface on the lid 204, that mechanically interlock with each other. As shown in <figref idref="f0007">FIGS. 7A and 7B</figref>, the features 244, 244' are tiny cylindrical posts and matching cylindrical cavities. Other types of microreplicated surfaces include, but are not limited to, pyramids, grooves, cones, prisms, spheres, and ellipsoids. Various microreplicated surfaces are described in more detail in <patcit id="pcit0005" dnum="US6315851B"><text>U.S. Patent No. 6,315,851 (Mazurek et al.</text></patcit>).

0041In some embodiments, the opposing surfaces 240, 242 on the lid 204 and liner 208 include features having undercuts that provide at least some degree of mechanical retention between these opposing surface 240, 242 along directions normal to the mating surfaces. Such undercuts could be provided by either microreplicated or non-microreplicated surfaces. One such microreplicated surface, characterized by mushroom-type hooks, is described in <patcit id="pcit0006" dnum="US5845375A"><text>U.S. Patent No. 5,845,375 (Miller, et al.</text></patcit>). In other embodiments, the opposing surfaces 240, 242 may be asymmetric. For example, the opposing surfaces 240, 242 could engage each other using a hook-and-loop mechanism, such as described in European Patent No. <patcit id="pcit0007" dnum="EP0258015A"><text>EP 0258015 (Ott, et al.</text></patcit>).

0042<figref idref="f0008">FIG. 8</figref> shows a container 300 according to still another embodiment having a liner 308 with a pair of hinged tabs 322 similar to those of containers 100, 200. The container 300, however, uses a latch 320 based on a releasable adhesive coupling between the tabs 322 and opposing surfaces of the lid 304. In some embodiments, a pressure sensitive adhesive 342 extends over either or both of the opposing surfaces of the tab 322 and lid 304, conveniently allowing finger pressure to secure the latch 320. Suitable pressure sensitive adhesives include, for example, 300LSE High Strength Acrylic, 300MP High Strength Acrylic, and 350 High Holding Acrylic double-coated adhesive tape provided by 3M Company (St. Paul, MN). Preferably, the pressure sensitive adhesive 342 has sufficient shear bond strength to provide a secure coupling between the lid 304 and the liner 308, yet can be subsequently detached from the lid 304 (or liner 308) to allow an operator to refill the container 300.

0043Yet another possibility is to provide a latch with a tabbed configuration similar to those in latches 220, 320, but using a hook and loop mechanism to secure the tab to the lid. For example, the tab could include a multiplicity of tiny hooks, while a mating surface on the lid includes a multiplicity of tiny loops that interlock and fasten these surfaces together.

0044In general, the latches 220, 320 can be released by grasping the distal edge of the tab 222, 322 and gently peeling it away from its opposing surface on the lid 204, 304. In some embodiments, the latch 220, 320 can use microreplicated surfaces, a hook and loop mechanism, or adhesive that is engineered to have a peel bond strength significantly lower than its shear bond strength. This feature can help preserve reliable retention of the lid 204, 304 on the liner 208, 308 under normal operating conditions (which subject the latch 220, 320 to shearing forces) while facilitating peel removal of the tab 222, 322 upon demand.

0045Use of microreplicated patterns and adhesives need not be exclusive or independent of each other. For example, the opposing surfaces on the tabs 322 and lid 304 could optionally have interlocking microreplicated features, like the latches 220 in the container 200. In some embodiments, one or more latches could use a pressure sensitive adhesive that is itself formed into a microreplicated pattern, as described in <patcit id="pcit0008" dnum="US5650215A"><text>U.S. Patent No. 5,650,215 (Mazurek, et al.</text></patcit>). Advantageously, the combination of the pressure sensitive adhesive 342 and interlocking microreplicated features could further enhance the retention between the lid 304 and the liner 308, while retaining the ability to easily release the latch 320.

0046Further aspects of the containers 200, 300 are essentially analogous to those already described with respect to the container 100 and shall not be discussed here.

0047<figref idref="f0009">FIGS. 9A and 9B</figref> show a container 400 outside the scope of the claims, in which a latch 420, that couples a lid 404 to a liner 408, has an essentially static configuration. In this mechanism, the latch 420 is integrated into the lid 404 and includes a multiplicity of penetrating features 460 that pierce a flange 414 of the liner 408. By extending at least partially through the flange 414, the penetrating features 460 releasably couple the lid 404 to the liner 408 in the manner shown in <figref idref="f0009">FIG. 9A</figref>. In this container, not covered by the claims, the penetrating features 460 are generally conical and rely on frictional engagement between the penetrating features 460 and the flange 414 to prevent accidental disengagement between the lid 404 and liner 408. Optionally but not shown, the features 460 could have undercuts to provide increase mechanical retention, as discussed earlier with respect to the microreplicated features of the latch 220.

0048As another option, the flange 414 of the liner 408 could have registered receptacles (not shown) that engage with the penetrating features 460 when the latch 420 is engaged. The receptacles could be sized to facilitate mutual engagement and disengagement of the lid 404 and the liner 408. Optionally, the receptacles could be disposed in a resilient polymeric material that elastically expands and contracts to facilitate passage of the penetrating features 460 without permanent damage to the flange 414 of the liner 408. As a time-saving feature, the penetrating features 460 could have a configuration whereby the act of securing the outer collar to the rigid cup (for example, by screwing the outer collar onto the cup) induces the latch 420 to assume its closed position by urging the lid 404 towards the liner 408.

0049It is noted that the penetrating features 460 are distinguishable from features of prior art embodiments because the penetrating features 460 pierce the flange 414 to secure the liner 408 and lid 404 to each other in a reversible manner (e.g. if desired, the penetrating features 460 can be subsequently plucked out of their openings in the flange 414 to remove the lid 404). To avoid interference between the penetrating features 460 and the rim of an outer cup surrounding the liner 408, the rim of the outer cup could include an annular groove that receives the penetrating features 460 when the flange 414 of the liner 408 is compressively secured between the lid 404 and the outer cup.

0050Yet another embodiment is illustrated in <figref idref="f0010">FIG. 10</figref>, which shows an enlarged view of a latch 520 integrally formed on a side wall 512 of a liner 508 used with a fluid container 500. Optionally, the latch 520 is made from the same material as the liner 508.

0051As shown, the latch 520 includes a tab 522 that is coupled to the side wall 512 by a hinge 521 represented by a strip of material with a reduced cross-sectional thickness to facilitate pivoting of the tab 522 relative to the side wall 512. The tab 522 has a generally flat body 568 and a terminal end 570 optionally provided with a friction enhancing texture 572 to assist an operator in grasping the tab 522 between thumb and forefinger without slippage when securing and releasing the latch 520. Located between the body 568 and the terminal end 570 is a clasping feature 574 that has an undercut configuration enabling the clasping feature 570 to extend over the outer edges of the lid 504 when the latch 520 is in its closed position.

0052To retain the tab 522 in its closed position, in which the latch 520 secures the lid 504 and liner 508 to each other, the side wall 512 of the liner 508 further includes a pair of flexible clips 576. The flexible clips 576 are resilient, clasp-like stubs that project outwardly from the cylindrical side wall 512 and include terminal hooks 578 pointing inwardly toward each other. The hooks 578 engage the lateral sides of the body 568 of the tab 522 in an interference fit when the latch 520 is in its closed position (not shown). Advantageously, the flexible clips 576 allow the latch 520 to be maintained in its closed position even when the tab 522, owing to its resilience, has a bias for springing back toward its open position, shown in <figref idref="f0010">FIG. 10</figref>. The flexible clips 576 also decrease the likelihood that the tab 522 will spontaneously disengage when suspending the liner 508 by the lid 504, as might be encountered when lifting the liner 508 out of a corresponding cup, particularly when filled with a high-solids coating fluid.

0053Optionally and as shown, there is a recess 582 in the peripheral edge of the lid 504 to accommodate the tab 522 when the latch 520 is in its closed position. In the depicted embodiment, the recess 582 matingly engages the clasping feature 574 of the tab 522 to help provide a secure coupling. Such a recess may also be present in any of the earlier described lid embodiments to provide sufficient clearance for the hinging of the tab. If so desired, this portion of the tab 522 can be received in the recess 582 such that the tab 522 is flush against the adjacent portion of the lid 504 when the latch 520 is closed, thereby decreasing the overall profile of the latch 520 and minimizing interference between the latch 520 and outer collar (if present).

0054If an outer collar is present in the embodiment of <figref idref="f0010">FIG. 10</figref>, it may be desired to incorporate into the outer collar a relief to accommodate the terminal end 570 of the tab 522, particularly if the tab 522 locks in a generally vertical position as shown.

0055In the aforementioned embodiments, it can be advantageous for the lid, liner, or both to be provided as disposable parts of a spray gun assembly, since these components contact the contents of the container. The cup and collar, which do not normally contact the contents of the container, can be reused. To provide even greater time savings to the end user, the manufacturer could also pre-fill the lid/liner assembly with a fluid to be dispensed, thus allowing an operator to conveniently drop the pre-filled assembly into an outer cup, secure the cup assembly with an outer collar, and then mount it to a suitable spray gun platform.

0056Any of these components can be manufactured from plastic using any of a number of processing methods known in the art. For example, either or both of the lid and liner can be injection molded in part or in whole. In the embodiment of <figref idref="f0010">FIG. 10</figref>, it is possible for the liner to include a molded annular structure that is manufactured separately and coupled to the side wall of the liner, where the molded structure provides the latch components that secure to the lid, as illustrated.

0057In one preferred method of making, not covered by the claims, the liner is provided by a thermoforming method where the a plastic sheet is heated to a pliable forming temperature, urged against either a positive or negative mold to form the sheet to the desired shape, and then trimmed to create the final product. This process enables the flange and latch to be made integral with the liner. In a preferred scenario, not covered by the claims, the tabs of a latch are coplanar extensions of a flange of the liner which are shaped by the molding step or, alternatively, created when the liner is trimmed. The hinge component of a latch may be provided, for example, by thermoforming the liner to include a thin webbing between an outwardly extending tab and a cylindrical side wall.

0058The aforementioned fluid containers are especially useful in high volume industrial painting applications. The containers facilitate the storage of leftover coating fluids as well as switching out pre-filled fluid containers between spraying operations to reduce or eliminate the lag time associated with repeatedly refilling a lined paint reservoir. The ability to secure the lid and liner of a container for long term storage also creates the possibility of maintaining an inventory of paints that can be rapidly dispensed and exchanged in a series of spraying applications.

0059In an exemplary method of storing a fluid in a container, not covered by the claims, an operator can transfer the paint (or some other fluid) into a collapsible liner, place the liner within a rigid cup or frame member, then use a latching member located on either the liner or the lid to fasten the liner and lid to each other, as described above. If desired, the liner can then be further secured to the lid by with the assistance of a collar, buckle, or other fastening mechanism as described earlier. If a fluid outlet is built into the lid (as in the embodiments above), a separate cap can be used to seal this opening prior to long term storage of the fluid container and its contents.

0060Advantageously, if the liner is self-supporting, the paint transfer step can occur either before or after the placement of the liner in the cup or frame member. Further, it is contemplated that the fluid container may not require the assistance of an additional fastening mechanism where the latch or latches maintain and/or enhance the fluid-tight seal between the liner and lid of the container.

0061The protrusions and receptacles situated on the surfaces of the lid and tab, respectively, may be reversed such that the protrusion is located on the tab while the receptacle is located on the lid.

0062The latch or latches between the lid and liner could assume various combinations of the above retaining features and mechanisms (e.g. protrusions, undercuts, adhesives, etc.). Moreover, the disclosed retaining features may be mixed and matched with mating surfaces in a manner not expressly shown in the figures. For example, the latch or latches could operate based on a PSA that adheres the flange of a liner to an opposing surface on a lid, or penetrating features could be disposed on respective surfaces of a tab hingedly coupled to the liner.