Patent Application
20190135505
The field of the invention is that of storage containers. More particularly, the invention deals with a ventilation system for maintaining atmospheric pressure within storage drums for chemical storage, transportation and mixing.
Storage drums are commonly used in industry for the storage, transport, and dispensing of liquids, pastes, gels, and powders. The ubiquitous 55-gallon drum may be made from metal, plastic, and the like and is typically equipped with a removable lid 10 such as shown in
Liquid material may be dispensed from such drums in a variety of ways. For example, liquid contents may simply be poured from one port. In other examples, a spigot or nozzle may be screwed into one port and the drum stored on its side so that liquid may be controllably dispensed by operation of the spigot or nozzle. Pumps such as hand pumps or electric pumps may be screwed into one port and operated to pump liquid from a drum. Such pumps have the advantage of allowing the drum to remain in a vertical orientation so that liquid does not leak from the port.
No matter the method used to remove material from one port, the second port must be at least partially opened so as to allow air to enter the drum and prevent buildup of a vacuum inside the drum as material is removed. Depending on the material stored in a drum, a port may need to be opened partially so as to allow for venting to prevent pressure from building up in the drum. Leaving a port open for venting purposes allows outside materials to potentially enter the drum and contaminate the material stored therein. If the material being stored in the drum is volatile then leaving one port open at all times may allow the material to evaporate. What is needed is a venting device for storage drums which allows for the automatic venting when excess pressure is present in a drum as well as for the ingress of air to prevent vacuum build up when dispensing material from the drum.
The above mentioned and other features and objects of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention. The exemplification set out herein illustrates an embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
The embodiments disclosed below is/are not intended to be exhaustive or limit the invention to the precise form disclosed in the following detailed description. Rather, the embodiment is chosen and described so that others skilled in the art may utilize its teachings.
Venting cap portion 22 as shown in
Venting insert portion 26 as shown in
First vent cover 36 is secured to venting insert portion 26 using snap-fastening pin 64 which passes through opening 72 in venting insert body 34. Pin 62 is held in place by tabs 73 (two in this exemplary embodiment) which expand or move away from one another once pin 64 passes through or is snapped through opening 72. Optionally, the pin 64 may be screwed, glued, or formed as a part of the venting insert body. First vent cover 36 is positioned so as to cover a plurality of venting holes 70 in venting insert body 34. In this example, first vent cover 36 is configured so as to prevent air or other gasses from passing into a storage container as indicated by direction arrow 100, but to allow gasses to pass out of a storage container as indicated by direction arrow 102 when they exceed a certain predetermined pressure, such as 14.9 psi. Once the pressure inside the storage container drops below the predetermined pressure, vent cover 36 returns to its unpressurized shape and prevents passage of gasses into or out of the container.
Second vent cover 38 is secured to venting insert portion 26 using snap-fastening pin 68, which passes through opening 74 in venting insert body 34. Pin 68 is held in place by tabs 76 (two in this exemplary embodiment) that exert a small urging force away from one another, such that when inserted through opening 74 (snapped into place) the tabs 76 expand or move away from one another after once pin 68 passes through opening 74. Optionally, the pin 68 may be screwed, glued, or formed as a part of the venting insert body. First vent cover 38 is positioned so as to cover a plurality of venting holes 66 in venting insert body 34. Second vent cover 38 operates in a similar manner as first vent cover 36, but second vent cover 38 operates to prevent the passage of air or other gasses out of a storage container as indicated by direction arrow 102, but to allow gasses to pass in to a storage container as indicated by direction arrow 100 when they exceed a certain predetermined pressure.
The exact pressure at which vent cover 36, 38 deflects and allows passage of gasses out of the storage container may be controlled by the material (such as rubber or SANTOPRENE; SANTOPRENE is a registered trademark of the Monsanto Company Corporation, 800 N. Lindberg Blvd., St. Louis, Mo., reg. no. 1081414) used to construct the vent cover, the cover's size, and its thickness. In some embodiments, pin 64, 68 holding vent cover 36, 38 in place is frictionally secured in insert body 34, and in others is threadedly connected to insert body 34 as well as operationally connected to vent cover 36, 38, such that by pushing/pulling (frictional engagement) or turning (threaded engagement) pin 64, 68, tension applied to cover member 36, 38 may be increased or decreased. Post tensioning of cover member 36, 38 allows a user to increase or decrease the predetermined pressure threshold required to actuate venting. For example, tension on cover 36 may be adjusted such that the predetermined threshold pressure on the cover is 14.9 psi (slightly greater than ambient atmospheric), 15.5 psi, 15.8 psi, 16.2 psi, or the like. Likewise, the threshold pressure on cover member 38 may be adjusted to be 14.55 psi, 14.50 psi, or the like. In these embodiments, cover members 36, 38 are typically made of metals such as steel, aluminum, or the like.
The pressure differential which operates first vent cover 36 is created when pressure builds up inside the storage container until it exceeds the air pressure outside the container. The pressure differential which operates second vent cover 38 is created when pressure drops (i.e., vacuum is created) inside the storage container until the air pressure outside the container exceeds the pressure inside the container by a sufficient amount. Such vacuum is usually generated by removing liquid from the container. When the air pressure outside the container exceeds the pressure inside the container by a predetermined amount the second vent cover deflects and allows air to pass in the direction of arrow 100 into the container to equalize the pressure. The exact pressure at which second vent cover 38 deflects and allows passage of gasses into the storage container may be controlled by the material used to construct the vent cover, the cover's size, and its thickness. Once the pressure inside the storage container increases above the predetermined pressure vent cover 38 returns to its unpressurized shape and prevents passage of gasses into or out of the container.
The use of two vent covers configured to allow passage of gasses in different directions allows for a single venting device to relieve pressure differentials caused by either an increase or a decrease of pressure within a storage container relative to ambient pressure without the container, while still maintaining a sealed container when there is no such pressure differential. As shown in this particular example, second vent cover 38 is larger than first vent cover 36. Such a configuration may be used where the material stored inside the container is not particularly volatile so that vacuum build up (i.e., a gradual decrease in pressure within the container) generated by the pumping of liquid from the container is more likely than excess pressure build up within the container from vapor or gas evolved from the material stored in the container. In other examples, the vent covers may be of a similar size or the first vent cover may be larger than the second vent cover, as desired. In still other examples, a filter may be attachable to the venting assembly to capture harmful vapors as they are vented through the first vent cover. The exact nature and composition of the filter and filtering medium would vary according to the material being stored in the container.
The various components of the disclosed invention may be made from a variety of suitable materials such as plastics, metal, composites, and the like. The materials used to construct the components may vary according to the nature of the material being stored in a particular container. The vent covers may be made out of plastic, composites, silicone, or other suitable material which has sufficient flexibility and strength so as to prevent deflection until a particular pressure differential is exceeded, and then return to an undeformed state once the pressure differential is relieved. In examples where ports or openings on storage containers use non-threaded openings or openings of non-standard sizes and/or shapes, the disclosed invention may be adapted by using means other than threaded engagement between the vent and the container. For example, the vent may be welded or secured using fasteners such as bolts or screws to a container.
Although the disclosed invention has been described above with reference to cylindrical storage drums, it is understood by one of ordinary skill in that art that the disclosed invention may be adapted to any sort of liquid or other storage container where venting is desired. In addition to 55-gallon drums, the disclosed invention may be adapted for use with smaller or larger drums, buckets, pails, barrels, tanks, and the like which are equipped with one or more access ports or openings.
In operation, venting assembly 20 is operationally connected to a storage drum (not shown) or other container adapted to be pressurized. The connection of venting assembly 20 to the storage drum is by any conventional method, such as through threaded engagement, interference fit, or the like. Typically, at least one gasket 46, 126 is operationally connected between body portion 24 and the drum (more typically between flange portion 28 and drum top 10) to prevent leakage at the venting assembly-drum interface. Typically, body portion 24 is engaged by one or more dogs 42 extending therefrom for tightening when threadedly engaging with the drum. Typically, dogs or tabs 42 each include a small through hole 45 for threading a wire therethrough, which may be muted onto the associated drum barrel and/or through other fittings to provide tamper evidence in the event of attempted removal of the venting assembly (plug body) 20. Cap portion 22 is typically engaged with body portion 24 to prevent a non-gastight seal over passage 40.
When the pressure within the drum substantially exceeds the ambient pressure without the drum, typically by about 1.5 P.S.I., more typically by about 1.0 P.S.I., and still more typically by about 0.85 P.S.I., diaphragm 36, 130 partially moves, deflects, and/or distorts to allow the flow or passage of gas and/or vapor through vent apertures 70 from within the drum to without the drum (and in the direction from distal end 43 of body 24 to proximal end 41 of body 24) until the pressure within the drum is substantially equal to that without the drum, i.e. until any pressure differential between the interior and exterior of the drum is minimized and/or resolved, wherein diaphragm 36, 130 resumes its original shape and once again prevents the passage of gas and/or vapor through vent apertures 70.
Likewise, when the pressure without the drum substantially exceeds the pressure within the drum, typically by about 0.19 psi., more typically by about 0.16 psi., and still more typically by about 0.14 psi, diaphragm 38, 134 partially moves, deflects, and/or distorts to allow the flow or passage of gas and/or vapor through vent apertures 66 from within the drum to without the drum (and in the direction from proximal end 41 of body 24 to distal end 43 of body 24) until the pressure without the drum is substantially equal to the pressure within the drum, i.e. until any pressure differential between the interior and exterior of the drum is minimized and/or resolved, wherein diaphragm 38, 134 resumes its original shape and once again prevents the passage of gas and/or vapor through vent apertures 66.
While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.
The present application claims priority to co-pending U.S. Provisional Patent Application Ser. No. 62/568,863, filed on Oct. 6, 2018, the disclosures of which are herein incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62568863 | Oct 2017 | US |
