This application claims the benefit of and priority from Provisional U.S. Patent Application No. 61/468,629, filed Mar. 29, 2011, incorporated herein by reference.
The invention relates to filters with pulsation dampeners, and more particularly to a replaceable filter cartridge with an inner-sealed pulsation dampener.
Filters with pulsation dampeners are known. An elastomeric dampener acts as a volumetric spring to compress during flow/pressure surges to increase system volume and reduce pressure spikes, and also to act as an accumulator, e.g. during the suction stroke of positive displacement pumps in such application.
The present disclosure arose during continuing development efforts in the above technology.
In
Basket 64 of filter cartridge 76 includes an axial extension section 78 extending axially away from the filter media and toward lid 68 and engaged by lid 68 at the latter's undersurface 80 to retain filter cartridge 76 in properly seated position in canister 14 upon closing by lid 68. Axial extension section 78 of basket 64 is directly engaged in touching contact at 80 with lid 68 without pulsation dampener 62 interposed therebetween. This is in contrast to
Pulsation dampener 62,
The disclosure provides a replacement filter cartridge 76 for a filter 60 having a housing provided by a canister 14 closed by a removable lid 68. The replacement filter cartridge has a pulsation dampener 62 mounted and sealed to the filter cartridge basket 64 at the inner diameter thereof.
In the prior art, during filter service change, the filter/dampener assembly can be difficult to remove from the housing since there are no features to afford adequate grip on the filter cartridge. Consequently, the end user must remove the elastomeric dampener and use pliers or other tools to grab any accessible portion of the filter basket to be able to remove it. Furthermore, the prior art does not prevent the filter from moving axially upwards into the housing cap or lid during operation and losing integrity of the seal of the upper O-ring, allowing a dirty to clean side bypass. In addition, the prior art does not prevent the user from not completely seating the filter element in the housing and creating a dirty to clean fluid bypass around the top O-ring. The present disclosure provides desirable sealing, and provides easy removal of the filter cartridge, and ensures that the filter cartridge is fully seated during installation and during operation to prevent dirty to clean fluid bypass. In the present disclosure, the dampener is sealed to the ID of the filter cartridge basket and held captive thereto by the noted grommet type undercut 82. This avoids the end user having to handle an assembly with loose parts. Upon insertion during assembly, the two OD radially sealing O-rings 48, 50 create axial resistance for resisting insertion. If the user does not fully seat the filter cartridge manually, the removal feature protrusion at axial extension section 78 of the basket will make contact with the inside surface or undersurface 80 of lid 68 which will force the filter cartridge 76 into position. Dampener 62 also creates a seal between the unfiltered fluid and atmosphere by sealing radially between filter cartridge basket 64 and axial protrusion tube 90 of housing lid 68. This sealing construction facilitates the noted filter removal aid feature. By moving the seal to the ID of the filter cartridge, the filter basket can be extended axially at 78 to create a grab handle for the user to grasp during filter service removal without the use of additional tools. This also provides the noted touch point at 80 on the undersurface of lid 16 to maintain a fully seated installed filter position upon completion of servicing.
In one embodiment,
The disclosure may be used in an inside-out flow implementation, as noted. In an alternate embodiment, the disclosure may be used in an outside-in flow implementation. In this embodiment, port 38 provides the inlet, and port 30 provides the outlet, and fluid to be filtered flows from outer diameter 36 of the filter radially inwardly through filter media 24 to inner diameter 34, with the outer diameter defining a dirty-fluid outer volume, and the inner diameter defining a clean-fluid inner volume.
In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The different configurations, systems, and method steps described herein may be used alone or in combination with other configurations, systems and method steps. It is to be expected that various equivalents, alternatives and modifications are possible within the scope of the appended claims. Each limitation in the appended claims is intended to invoke interpretation under 35 U.S.C.§112, sixth paragraph, only if the terms “means for” or “step for” are explicitly recited in the respective limitation.
Number | Date | Country | |
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61468629 | Mar 2011 | US |