Gas separation – Combined or convertible – In vented container
Reexamination Certificate
1999-11-12
2001-10-23
Simmons, David A. (Department: 1724)
Gas separation
Combined or convertible
In vented container
C055S385100, C055S502000, C210S321750, C604S333000
Reexamination Certificate
active
06306191
ABSTRACT:
The present invention relates to a sanitary seal and its use in a vent system. More particularly, it relates to a sanitary seal and vent used on filter cartridges.
BACKGROUND OF THE INVENTION
In the processing of liquids through devices such as filters, it is well known that gases are formed within the fluid often within the filter itself. These gases are either gases which had been entrained or dissolved within the fluid and which have now come out as bubbles within the liquid or are introduced into the fluid during processing.
These gases need to be removed in order to have efficient filtration. Gas tends to block portions of the filter surface making them unusable for filtration. When enough gas is formed on the filter surface, the filtration process essentially stops.
Additionally, many manufacturers of these liquids prefer or require that no gas be contained or visible within their finished product. Therefore it is important if not imperative to remove the gas.
Typically, vents are formed on the upstream side of the filter housing so as to allow for the removal of gas from the liquid. The venting must be done in a manner that maintains a sanitary seal between the vent opening and the outside environment when the vent is closed.
These vents are sealed with a push/pull valve design as shown in prior art
FIG. 1. A
vent stop
10
is mounted within the opening
12
of the vent
14
. The stop selectively opens and closes the vent
14
via a series of O-rings
16
A and
16
B. The vent
14
is opened by pulling the stop
10
outward until a passageway
18
A is established with the passageway
18
B of the vent opening
12
. Gas that is at a higher pressure within the filter housing than the outside atmosphere flows from the inside of the housing to the outside of the housing via the passageways
18
A and
18
B. The vent
14
is closed by pushing the vent stop
10
back into the vent opening
12
so the passageway
18
A is against the inclined portions
20
of the vent opening
12
which prevent any fluid (liquid or gas) from exiting the vent
14
.
Such vents are required on many filters because venting must be done on a periodic basis to prevent gases from building up inside the filter such that performance is compromised. Typically, gas build up diminishes the efficiency of filters and the vents must be periodically opened to vent the accumulated gases.
To determine if accumulated gases are affecting performance, one may monitor the pressure drop of the filter (increases by a set % require venting) or throughput (decreases in a set % require venting). One may also dispense with such monitoring and merely schedule periodic filter venting.
A problem with prior art vent designs is that the vents need to be small, but are not ergonomically designed. They have an outer knurled surface designed to be manipulated in a cam fashion that is bruises the hands. Also, the cam action required coupled with the strong hand action needed to actuate the cam can result in de-coupling the vent stop from the vent housing or stripping the cam from the housing.
Another issue is that the prior art design does not allow one to open the vent sufficiently so as to allow the gas to escape in a reasonable amount of time. But, one does not want to open the prior art vent so quickly that the sanitary seal is compromised, such as actually pulling the stop off the vent or more commonly, fluid leaks out of the vent and along the outside of the vent where it is lost (on prior art vents that have only a single o-ring).
What is needed is a new sanitary seal and vent design using that seal which overcomes these problems. The present invention provides such a solution.
SUMMARY OF THE INVENTION
The present invention relates to a seal, a vent for filter housings incorporating said seal and a device for recovering degassed fluids that incorporates the seal and vent.
The present invention provides a seal design having a first outer seal having a closed outer periphery that isolates a first inner area from the outside environment and a second inner seal formed along a portion of the inner surface of the first outer seal and forming a second inner area within the first inner area and which is isolated from both the first inner area and the outside environment.
The seal is incorporated into a vent for a filter housing having an opening contained within a vent area and the opening being offset from the center of the vent area. The opening establishes a fluid pathway from the interior to the exterior of the filter device. The inner seal surrounds the vent opening. The outer seal also surrounds the vent opening at one of its ends and surrounds the entire periphery of the vent area so as to isolate the vent area from the area outside of the vent area. A vent cap is secured to the vent housing such that it is movably fixed to the vent housing and its periphery contacts the outer periphery of the seal such that the vent area is enclosed.
The cap has an exhaust port which when in alignment with the vent allows fluid to flow out of the housing interior. The exhaust port is offset from the center of the cap and is designed to align with the offset opening of the vent. The cap is either moved in a linear or rotational motion and the vent opening and cap opening are always contained within the area defined by the outer seal so as to form a sanitary seal whether the cap is positioned to vent or not.
Also disclosed is a sanitary recovery system utilizing the seal and vent of the present invention.
It is an object of the present invention to provide a first seal having a second seal formed as part of its inner surface.
It is a further object of the present invention to provide a seal having a first outer seal having a closed outer periphery that divides and isolates a first inner area from the outside environment and a second inner seal formed along a portion of the inner surface of the first outer seal and forming a second inner area within the first inner area and which is isolated from both the first inner area and the outside environment.
It is an additional object of the present invention to provide a seal having a first outer seal formed such that its periphery seals a first selected area from an outside environment and a second inner seal formed as part of the inner surface of the outer seal within the first selected area, the periphery of the second seal forming a second selected area which is sealed from both the first selected area and the outside environment.
It is another object of the present invention to provide a vented filter housing comprising a housing, a vent opening contained within a vent area, the opening being offset from the center of the vent area, the opening establishing a fluid pathway from the interior to the exterior of the filter, a seal having an inner seal and an outer seal, the inner seal being formed as part of the inner periphery of the outer seal, the inner seal surrounding the vent opening, the outer seal also surrounding the vent opening and surrounding the entire periphery of the vent area so as to isolate the vent area from the area outside of the vent area and a vent cap secured at its outer periphery to an outer periphery of the vent area, the cap having an opening in its bottom portion in fluid communication with an exhaust port, the cap opening being offset from the center of the bottom of the cap so it can be aligned with the offset opening of the vent to facilitate venting.
It is an object of the present invention to provide a closed loop venting/liquid recovery system that includes the vent of the present invention as well as a channel from the exhaust port to a receptacle positioned to receive the effluent from the exhaust port. It would be preferable, where sterility is desired, for the channel is isolated from the outside environment.
REFERENCES:
patent: 4449970 (1984-05-01), Bevan et al.
patent: 4875899 (1989-10-01), Holtermann
patent: 5372594 (1994-12-01), Colacello et al.
patent: 5609757 (1997-03-01), Schiavo et al.
patent: 5725645 (1998-03-01), Wickland et al.
patent: 5733271 (19
Almasian Joseph M.
McInerney Kevin G.
Nguyen Chau
Cook Paul J.
Hubbard John Dana
King Timothy J.
Millipore Corporation
Pham Minh-Chau T.
LandOfFree
Sanitary seal design and vent using such seal does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Sanitary seal design and vent using such seal, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sanitary seal design and vent using such seal will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2599534