Venting cap

[0002] This invention relates to bottle caps which when screwed on a bottle allow for the venting of gases generated in the bottle.

[0003] Shampoos, cold creams and other cosmetics are typically prepared under heat and are poured into plastic containers such as bottles usually while still hot. The plastic bottles containing the hot cosmetic material are capped, trapping the hot gases generated by the hot cosmetics. When capped, a lower or inner surface 10 of the cap top seats against the mouth 12 of the bottle 14 forming a seal (FIG. 1). Consequently, if capped immediately after filling, the gases generated by the hot cosmetics generate a pressure within the bottle. The hot pressurized gases cause the plastic bottle to form flat spots. This condition is commonly referred to as “bottle paneling.” Moreover, the increase in pressure within the bottle may cause the bottles to explode creating a hazardous condition. One way to avoid pressure build-up and paneling is to fill the bottles while the cosmetics are cold. When cold, the cosmetics are thick and viscous, thus, having reduced fluidity. Consequently, the filling process is slowed requiring a longer time to fill the bottles.

[0004] A typical way of avoiding pressure build-up and paneling is to fill the bottles with the hot cosmetics and wait for a period of time, typically in the order of 24 hours, before capping the bottles. This approach also slows down the filling process adding to production costs.

[0005] Another common way of preventing bottle paneling, incorporates a grooved liner fitted into the bottle cap. The liner typically has a surface that has grooves forming a cross-hatched pattern as well as holes penetrating its thickness. The bottom surface of the liner is covered with a gas permeable layer. When fitted into the cap, the grooved surface of the liner is mated to the lower surface of the cap top. When the cap is screwed onto the bottle, the holes provide a path for gas generated within the bottle to travel to the grooves which provide a path to the inner circumference of the cap from where the gas can escape through the space created between the cap rim and the bottle neck to the exterior of the bottle.

[0006] Thus, there is a need for a fail safe bottle cap that would allow for venting of gases generated in a bottle so as to allow for the capping of bottles immediately after being filled with hot liquids.

[0007] A bottle cap is provided which when screwed on to a bottle provides a path for gases generated in the bottle to escape from the bottle through a spiraling space formed in the threaded region between the inner surface of the bottle cap rim and the outer surface of the bottle neck.

[0008] The bottle cap includes one or a plurality of concentric preferably circular ridges formed on the inner surface of the cap top. Each of these ridges is designed to sit on the rim of the bottle mouth when the cap is threaded onto the bottle neck. A slot or multiple slots are formed in each ridge. The slots between adjacent ridges may be staggered or may be aligned.

[0009] In an alternate embodiment, grooves are formed on the inner surface of the cap top. When the bottle cap is threaded onto the bottle neck, the grooves extend from a location on the inner surface of the cap top within the mouth of the bottle neck to a location extending to the outer edge of the mouth rim or beyond the mouth rim of the bottle neck.

[0010] With every embodiment, when the cap is threaded onto the bottle, gases generated within the bottle can escape across the rim of the mouth of the bottle neck through the slots or through the grooves and through the threaded region between the inner surface of the cap rim and the outer surface of the bottle neck to the exterior of the bottle.

[0011] In an alternate embodiment, the ridges or grooves are formed on a disc which is fitted in the cap over the cap top inner surface. The disc may be glued on the cap inner surface.

[0012] A liner may also be used with the caps of the present invention. This liner is typically fitted over the inner surface of the cap top. An opening is formed in the liner to allow for gases generated in the bottle to penetrate the opening and escape through the slots or grooves formed on the cap top or disc.

[0013] FIG. 1 is a partial cross-sectional view of a typical cap threaded onto a bottle neck.

[0014] FIG. 2 is a partial cross-sectional bottom view of a cap of the present invention depicting a ridge formed on the inner surface of the cap top having slots formed therethrough.

[0015] FIG. 3A is a partial cross-section of a cap of the present invention threaded on to a bottle neck.

[0016] FIG. 3B is a perspective view depicting the flow of gases through the threaded space formed between the bottle neck outer surface and the cap inner surface.

[0017] FIG. 4 is a partial cross-sectional bottom view of a cap of the present invention having multiple slotted concentric ridges formed on the inner surface of the cap top.

[0018] FIG. 5 is a partial cross-sectional bottom view of a cap of the present invention having multiple concentric ridges formed on the inner surface of the cap top having staggered slots formed therethrough.

[0019] FIG. 6 is a partial cross-sectional bottom view of a cap of the present invention having grooves formed on the inner surface of the cap top.

[0020] FIG. 7 is a perspective view of a liner for used with any of the caps of the present invention.

[0021] FIG. 8 is a side view of a cap having a flip top.

[0022] FIG. 9 is a side view of a cap having a moveable spout.

[0023] FIG. 10 is a cross-sectional view of cap fitted with a disc according one embodiment of the present invention.

[0024] FIG. 11 is a cross-sectional view of cap fitted with a disc according to an alternate embodiment of the present invention.

[0025] FIG. 12 is a top view of the cap with disc of the embodiment show in FIG. 11.

[0026] FIG. 13 is a partial cross sectional view of a cap threaded onto a bottle neck and incorporating a disk having a ridge and a slot there through.

[0027] FIG. 14 is a partial cross sectional view of a cap threaded on a bottle neck and sandwiching there between a disk having a plurality of grooves which extend beyond the rim of the bottle neck.

[0028] A cap typically consists of a disc shaped top portion 24 from which extends an annular wall or rim 26 (FIG. 2). Threads 28 are formed on the inner surface 30 of the annular wall 26 for threading on threads 32 formed on the outer surface 34 of a bottle neck 36 (FIG. 3). The end of the bottle neck has a mouth 40 defined by a rim 42.

[0029] In a first embodiment, the cap of the present invention includes a circular ridge 44 formed on the inner surface 46 of the cap top portion (FIG. 2). The circular ridge diameter is smaller than the outer diameter of bottle rim, but greater than the inner diameter of the bottle rim defining the mouth. In this regard, when the cap is threaded onto the bottle neck, the ridge 44 sits on the bottle neck rim 42 (FIG. 3A).

[0030] One or more slots 48 are formed radially across the ridge. If more than one slot is formed, preferably the slots are equidistantly spaced along the ridge circumference. Preferably, four slots are formed spaced at 90° intervals around the ridge.

[0031] When the cap is threaded onto the bottle, the ridge sits on the rim 42 of the bottle neck. A seal 50 is formed between the ridge and the bottle mouth. The slots, however, provide a path for gas to escape from the bottle through the slots and out through the threaded spiraling space 52 between the inner surface of the cap annular wall and the outer surface of the bottle neck as shown by arrows 54 (FIG. 3A) or arrows 55 (FIG. 3B).

[0032] In an alternate embodiment, instead of a single ridge, multiple concentric spaced apart ridges 56 are formed (FIG. 4). Again, preferably each ridge should have a diameter that is smaller than the outer diameter of mouth of the bottle to be capped but greater than the inner diameter of the mouth of the bottle to be capped so that they can all mate with the bottle mouth rim 42 when the cap is threaded on to the bottle. At least a single slot 58 is formed radially across each of the ridges. If more than one slot is formed, preferably the slots would be equidistantly spaced around the concentric ridges. The concentric ridges provide multiple ridge surfaces for sealing with the bottle mouth rim, whereas each slot provides a path for venting to the outside.

[0033] In another embodiment, multiple concentric spaced apart ridges 60, 62, 64 are formed on the inner surface 46 of the cap top portion (FIG. 5). These ridges form grooves 68 between them. Again, these circular ridges have diameters such that they will sit on the rim 42 defining the mouth of the bottle neck when the cap is torqued onto the bottle. Staggered radial slots 70, 72, 74 are formed across the ridges. Preferably each slot is formed across a single ridge. At least one slot 70, but preferably two, are formed on the innermost ridge 60. When more than one slot is formed on a ridge, the slots should preferably be equidistantly spaced around the ridge. Similarly, one, or preferably two, slots 72 are formed on the ridge 62 immediately adjacent the innermost ridge 60. The slot or slots 72 should not be aligned with the slots 70 formed on the innermost ridge. If two slots 72 are formed, preferably, they are each located at a 180° from each other and spaced 90° away from slots 70 formed on the innermost ridge 60. One, or preferably two slots 74 are then formed on the next adjacent ridge 64. Preferably, these slots are aligned with the slots 70 formed on the inner most ridge 60. This pattern is preferably repeated until slots are formed on all the ridges formed on the cap top portion inner surface. Alternatively, the location of the slots on each ridge may be arbitrary or may be in any other preselected pattern. Moreover, each slot may span more than one ridge and/or the number of slots penetrating each ridge may be different from ridge to ridge.

[0034] When the cap is torqued onto the bottle neck, the ridges are seated on the rim 42 of the bottle neck forming a seal. The slots provide a path for gas to escape. Gas will first escape through the slots 70 formed on the innermost ridge 60 and travel in the groove 68 formed between the innermost ridge 60 and its adjacent ridge 62 until it reaches the slots 72 formed on the adjacent ridge 62 and then escapes through those slots. The gas then follows the various slot and groove paths until it exits through the threaded space 52 between the cap annular wall inner surface and the bottle neck outer surface.

[0035] In a further embodiment, grooves 76 may be formed on the inner surface 78 of the cap top portion inner surface 46 (FIG. 6). These grooves should preferably span to the edge 80 of the inner surface, i.e., the location where the inner surface of the cap top portion intersects the annular wall 82 of the cap, or span to at least a location at/or beyond the outer edge of the bottle neck rim 42 when the cap is torqued onto the bottle neck. Preferably, multiple chord-wise grooves are formed across the inner surface 46 of the cap top portion. The grooves may be parallel to each other and may also cris-cross each other. In the embodiment shown in FIG. 6, the grooves cris-cross each other forming squares. When the cap is torqued onto the bottle neck, the inner surface 46 of the cap top will seat against the rim 42 of the bottle neck. The inner surface 46 of the cap top portion will form a seal with the rim 42 of the bottle neck. The grooves 76, however, will provide a path for gasses formed in the bottle to escape across the rim of the bottle neck and through the threaded space 52 between the cap annular wall inner surface and the bottle neck.

[0036] The caps of the above described embodiments while allowing gas to vent would also allow some of the liquid to vent if the bottle were turned upside down and squeezed. When squeezed, the liquid material will travel through the slots formed on the ridges and in the later embodiment through the grooves 68. The liquid material would eventually gel in the slots and/or grooves sealing the slots and grooves. Thus, once the gas generated in the bottle has vented, the slots and/or grooves can be sealed by squeezing some of the liquid material through the slots or grooves as described above, thereby, preventing the escape of any further liquid from the capped bottle.

[0037] With all of these embodiments, the grooves, ridges and slots may be machined into the cap which is typically made of a hard plastic material. Alternatively, the grooves, ridges and slots may also be formed by a molding process. The cap with grooves, or ridges and slots may be formed by a single molding process. Alternative the grooves, or ridges and slots may be formed by a combination of molding and machining processes.

[0038] Because the grooves or ridges are made from the same hard plastic material as the cap, they are not susceptible to collapsing when under compression, as for example, when compressed against the rim 42 of the bottle mouth under normal cap torquing conditions.

[0039] With any of the aforementioned caps, a liner 84 may be used if necessary (FIG. 7). Typically, the liner will sit against the ridges or the grooved inner surface of the cap top portion. To allow for venting through the liner, at least a hole 80 should be formed through the liner thickness 88. The hole should preferably have a diameter between about 0.010 to 0.015 inch. The liner thickness should preferably be between about 0.015 and 0.020 inch.

[0040] Moreover, any of the aforementioned embodiments may be incorporated in non-conventional caps, such as caps having a flip top or a moveable spout. With flip caps 100, the top 120 of the cap is hingedly connected to the annular wall or rim 126 of the cap (FIG. 8). In this regard, the top can be flipped open to allow for the pouring out of the contents of the bottle. With spout caps 200, a spout 90 is incorporated on the cap top portion 220 of the cap 200 (FIG. 9). The spout can be rotated from a closed position 90 to an open position 92. When in an open position, a path is provided allowing for the pouring out of the contents of the bottle. With either type of cap, the ridges or grooves are also formed on the inner surface of the cap top portion as described herein.

[0041] Furthermore, the ridges or grooves may be formed, preferably by a molding or a machining process, on a disc 300 made from a hard or semi-hard material such as plastic (FIGS. 10,11,12,13 and 14). The disc is sized such that it can fit and sit against the inner surface 46 of the cap top portion 24 and such that the ridges 344 (FIGS. 11,12 and 14) or grooves 376 (FIG. 14) can mate with the bottle neck rim 42 which defines the bottle mouth 40 as described above. In this regard the disc may be used with conventional caps to provide the necessary venting so as to prevent bottle paneling. Moreover, since the disc is made from a hard or semi-hard material, the risk of collapsing of the ridges of grooves which may prevent the venting of gases is decreased. The thickness of the disc should preferably be in the order of 0.030 inch. The disc may be glued to the inner surface of the cap top portion using an adhesive compatible with the contents of the bottle.

[0042] The ridges 44 or grooves 376 are formed on one surface 302 of the disc, with the opposite surface 304 being flat (FIGS. 10,11,12 and 14). In one embodiment, the disc can be mated to the cap with its flat surface 304 against the cap top portion 24 inner surface 46 (FIGS. 10 and 13). In another embodiment, the disc is mated to the cap with its ridged or grooved surface 302 against the inner surface 46 of the cap top portion (FIG. 11). With this embodiment, the flat surface side of the disc mates with the bottle mouth when the cap is torqued onto the bottle. Moreover, with this embodiment, the diameter of the disc should be smaller then the inner diameter of the cap annular wall 26 such that a gap 306 is defined between the annular wall 26 and the disc edge 308. An opening 310 is formed through the thickness of the disc to allow the gases generated in the bottle to travel from the bottle through the opening and to the grooved or ridged surface 302 of the disc. From there the gas travels in the grooves or through the slots in the ridges and through the gap and through to the threaded space 52 (FIG. 3) between the cap annular wall inner surface and the bottle neck outer surface.

[0043] With this latter embodiment, i.e., the embodiment where the ridged surface is mated to the inner surface of the cap top portion, the ridges act as a spacer to separate the disc from the inner surface of the cap top portion. Moreover, with this embodiment, to prevent the bending of the disc when the cap is threaded onto the bottle, the disc should be positioned such that a ridge is located over the bottle neck rim 42.