FIELD OF THE DISCLOSURE

The present disclosure relates to liquid filters. It particularly concerns liquid filters which utilize a serviceable filter cartridge that has a preferred seal arrangement and, in some instances, no axial load support liner. The liquid filters can be used for a variety of applications. Assemblies and methods of preparation and use are provided.

BACKGROUND

Liquid filters are used for a variety of applications, for example to filter lubricating fluids, fuels or hydraulic fluids. During use, liquid to be filtered is passed through a filter media, as filtration occurs. A well-known configuration, is to position the filter media as a cylinder surrounding a central clean liquid volume, with filtration flow occurring with an outside to inside (out-to-in) flow through the filter media. In other arrangements filtering flow is from inside the cartridge to outside (in-to-out).

In many instances, the filter media is provided in the form of filter cartridge, in extension between first and second, opposite, end caps. Typically, the arrangement is also provided with a liner. For an out-to-in flow, an inner liner provides for both: (a) radial support of the media against collapse or damage, due to radial pressure during normal use; and (b) axial support against cartridge collapse and damage. Examples of filter cartridges which utilize such constructions, are described for example in WO 02/070869 A1 published 12 Sep. 2002, (FIGS. 1 and 2), the complete disclosure of WO 02/070869 being incorporated herein by reference.

With an in-to-out flow, an outer liner can be used to provide media radial support and also axial support.

In many assemblies, the filter cartridge is constructed as a removable and replaceable (i.e., serviceable) component, see for example FIGS. 1 and 2 of WO 02/070869 A1. It is desirable to provide for liquid filter designs that allow for desired options in construction of service cartridges.

SUMMARY

According to the present disclosure, a liquid filter cartridge is provided. A liquid filter cartridge generally has first and second opposite end caps, with media extending therebetween. The media is configured to define an open central volume, which in use defines an internal receiving volume for liquid. At least one of the end caps is an open end cap, i.e., it has an aperture providing fluid flow communication with the internal volume. In some applications both end caps are open end caps. In some embodiments, the liquid filter cartridge is configured for out-to-in flow, during filtering; although alternatives (for in-to-out flow) are possible.

Preferred seal arrangements are provided for one or more of the end caps. In preferred applications, the seal is provided at selected locations for advantageous net surface axial forces on one or more of the end caps, in use. In some applications a seal arrangement is provided with respect to each end cap, in order to provide for a preferred level of surface axial force balance.

Example assemblies are provided. In addition methods of design, assembly and use are described. Also, techniques for estimating the net axial surface force operating on one or each end cap, in the overall filter cartridge, are provided. Also, some preferred seal configurations are described and shown.

