Abstract: A filtering system (10) is provided for filtering working fluid from a machine (12) and includes a cleanable filter (16) and a centrifuge (82) where filter capacity is too low for a permanent filter yet flow rate is too high for a centrifuge. The system transfers the contaminant storage function from the cleanable filter to the centrifuge. A simple effective centrifuge is provided.

Abstract: An open flow fluid filter has a pleated main filter element having a plurality of pleats in a closed loop having an outer perimeter defined by a plurality of outer pleat tips, and an inner perimeter defined by a plurality of inner pleat tips. The loop has a hollow interior extending along an axis. Fluid to be filtered flows through the main filter element from an upstream dirty side to a downstream clean side, and flows axially in the hollow interior. The main filter element has an axial flow passage extending along the axis and circumscribing the hollow interior and has a flow perimeter greater than the inner perimeter. A safety filter element downstream of the main filter element filters both the axial flow in the hollow interior and additional flow between the flow perimeter and the inner perimeter. A filter with additional flow is also provided.

Abstract: A filter (20) has a removable cover (30) releasably engaging and gripping an end cap (40) of a filter element (34) including upon removal from the filter housing (22). The cover has a plurality of axially extending cantilever legs (102, 104) gripping a mushroom-shaped boss (118) on the end cap.

Abstract: An air/oil separator tank (10, 60) has a separator element (12, 62) including coalescing media (14, 64). A separate downstream drain layer (22, 72) removes the separated coalesced oil and passes clean air. The separator element is removable from the tank for replacement. The drain layer is permanently attached to the tank.

Abstract: An air filter element has a cylindrical filter media sleeve axially slidable along and around an inner liner from either axial end of the sleeve. First and second end caps at distally opposite axial ends of the liner and sleeve each have a central aperture, the aperture in the first end cap providing air flow therethrough in communication with the hollow interior of the liner, the aperture in the second end cap retaining a closing cover. The cylindrical filter media sleeve extends axially along the inner liner and is axially retained between the cover and the first end cap. The cover is removably mounted to the second end cap in snap-in relation and axially retains the sleeve on the inner liner.

Abstract: A filter (12) has a resiliently compressible thermally and chemically resistive combined unitary frame and gasket member (22) extending along its perimeter (18) and supporting a filter media element (16) and sealed to both the filter media element and the housing (20). One or more flange portions (34, 72, 94, 96, 118, 130) have one or more hollow channels (36, 74, 90, 92, 120, 132) deformed by engagement with the housing and reducing required closure force of the housing thereagainst.

Abstract: A screen-type spark arrestor (34) may be efficiently and compactly mounted in a muffler (10). A tubular screen is coaxial with an exhaust pipe (24) and has a first end (36) axially spaced from the pipe and star-crimped closed, and a second end (38) axially overlapping the pipe in concentric relation and crimped thereto by a crimp ring (40). The combination is mounted as a modular component by a flange (22) closing the muffler housing (12).

Abstract: An inside-out reverse flow air filter element (20) has a resiliendtly compressible molded lower end cap (48) having molded drainage surfaces including a molded raised central dome (72) shedding moisture radially outwardly and downwardly, a plurality of molded drainage holes (70, 74, 76, 78) spaced radially outwardly of and below the top of the central dome, and a plurality of radial segments (98, 100, 102, 104, 110, 112, 114, 116), an annular trough (80) and tapered slope surfaces (82, 84) providing desired drainage. A mold (130) has a plurality of upstanding segments (136, 138, 140, 142) having posts (144) and ramps (146) forming the drainage structure, and locator faces (152) engaging, guiding and locating the annular filter media (34) in the mold.

Abstract: A filter filters fluid flowing along an axial flow direction and includes a plurality of concentric cylindrical pleated filter elements having a common axis. A plurality of annular radial gaps between filter elements provide additional flow axially through the filter, providing equalized flow and reducing restriction. In further embodiments, a central filter element is concentrically surrounded by a cylindrical pleated outer filter element and provides additional flow axially therethrough.

Abstract: A filter (200) filters fluid flowing along an axial flow direction (14) and includes a plurality of panels (206, 208, 240, 242) of pleated filter elements (44), each filter element having a plurality of pleats defined by wall segments (50) extending along a transverse direction (210) between first and second sets of pleat tips at first and second sets of axially extending bend lines (46, 48), the transverse direction (210) being perpendicular to the axial direction (14). Each of the panels (206, 208, 240, 242) extends along a lateral direction (212) perpendicular to the axial direction (14) and perpendicular to the transverse direction (210). The wall segments (50) extend axially between upstream and downstream ends (52, 54), and define axial flow channels (55) therebetween which are alternately sealed at the upstream and downstream ends.

Abstract: A filter (110) is provided with a fixture (70) having a first set of axially extending inner pillars (72, 74, 76, 78) defining a first cylinder (80) along inner bend lines (34) of inner pleat tips (32) of an annular pleated filter element (22), a second set of axially extending outer pillars (82, 84, 86, 88) defining a second cylinder (90) extending along outer bend lines (38) of outer pleat tips (36) of the filter element (22), inner and outer circumferential rings (92 and 94) extending around the respective first and second sets of pillars and circumferentially spacing and supporting such pillars, and a plurality of radial spokes (100, 102, 104, 106) at an axial end (98) of the fixture (70), each spoke extending radially between a respective inner and outer pillar and radially spacing and supporting respective inner and outer pillars in radially spaced concentric relation defining a reception annulus (108).

Abstract: A diesel engine crankcase ventilation filter is provided by a flat low profile filter housing extending in a horizontal plane and having an upper planar horizontal surface, a lower planar horizontal surface, and side surfaces extending between the upper and lower surfaces. A planar horizontal flat panel filter element extends parallel to the upper and lower surfaces. The housing has an upper plenum between the flat panel filter element and the upper surface, and a lower plenum between the flat panel filter element and the lower surface, an inlet receiving oil and air from the diesel engine and supplying same along an inlet path to the upper plenum to flow downwardly through the flat panel filter element to the lower plenum, a first outlet outputting air along a first outlet path from the lower plenum, and a second outlet outputting oil along a second outlet path from the lower plenum.

Abstract: A flat panel filter element is provided for a diesel engine crankcase ventilation filter having a flat low profile filter housing extending in a horizontal plane. The flat panel filter element has media, including coalescing media, spanning a horizontal supporting and sealing perimeter border frame and passing flow downwardly therethrough.

Abstract: A muffler (20) is provided by upstream and downstream outer shells (28 and 30) and a single sole internal baffle (32 or 110 or 120), all three of which are joined to each other around an outer peripheral edge (34). The internal baffle defines a first chamber (36) between the internal baffle and the upstream outer shell. The internal baffle has an extension portion (38) extending away from the upstream outer shell and toward and into the downstream outer shell and forming second and third chambers (40 and 42) between the internal baffle and the downstream outer shell and forming multiple sound attenuating tubed passages (44 and 46, 114, 124 and 128) bounded by the downstream outer shell and the extension portion and connecting the second and third chambers on distally opposite ends (48 and 50) of the extension portion. The baffle has an opening (52) therethrough adjacent the extension portion and connecting the first and second chambers.

Abstract: An air filter housing (12) includes twist and lock structure (46) having a first position (FIGS. 5, 6) permitting axial movement (120) of a cover (44) and base (38) relative to each other, and being rotatable in a first direction (48) from the first position (FIG. 6) to the second position (FIG. 7), and in the second position (FIG. 7) preventing axial movement of the base (38) and cover (44) relative to each other, and being rotatable in a second opposite direction (78) from the second position (FIG. 7) to the first position (FIG. 6). Anti-rotation lock structure (80) provides a rotational retention force holding the twist and lock structure (46) in the second position (FIG. 7).

Abstract: A filter is composed of filter media having the following characteristics in combination: a) the filter media has a greater affinity for the filtered fluid than for contaminants in the fluid, and wherein the work of adhesion between the filter media and the contaminants is less than the work of adhesion between the filter media and fluid, and wherein the filter media is preferentially wetted by the fluid relative to the contaminants; b) the filter media is composed of fibers having a defined surface area ratio facilitating fewer attachment sites for contaminants, and, in the case of cleanable reusable filters, facilitating cleansing backwash of the cleanable reusable filter by cleansing fluid along a reverse flow backflush path; c) the filter media has a thickness of 0.025 to 0.075 inch, 0.7 to 2.

Abstract: An open flow fluid filter has a pleated main filter element having a plurality of pleats in a closed loop having an outer perimeter defined by a plurality of outer pleat tips, and an inner perimeter defined by a plurality of inner pleat tips. The loop has a hollow interior extending along an axis. Fluid to be filtered flows through the main filter element from an upstream dirty side to a downstream clean side, and flows axially in the hollow interior. The main filter element has an axial flow passage extending along the axis and circumscribing the hollow interior and has a flow perimeter greater than the inner perimeter. A safety filter element downstream of the main filter element filters both the axial flow in the hollow interior and additional flow between the flow perimeter and the inner perimeter. A filter with additional flow is also provided.

Abstract: An air filter housing (12) includes twist and lock structure (42) having a first position (FIGS. 5, 7, 10) permitting axial movement (66) of a cover (34) and base (36) relative to each other, and being rotatable in a first rotational direction (44) from the first position to a second position (FIGS. 4, 6, 9, 12), and in the second position preventing axial movement of the base and cover relative to each other, and being rotatable in a second opposite rotational direction (64) from the second position to the first position. Anti-rotation lock structure (70, 110, 140) provides a rotational retention force holding the twist and lock structure in the second position. The anti-rotation lock structure includes an arm (74, 112, 142) flexibly bendable about a bend line extending parallel to the axis (14) of the housing.

Abstract: A filter element (202, 250) includes pleated filter media (26) having a plurality of pleats (28) in a closed annular loop having an outer perimeter (30) defined by a plurality of outer pleat tips (32), an inner perimeter (34) defined by a plurality of inner pleat tips (36), the loop having a hollow interior (38) extending along an axis (40), wherein fluid to be filtered flows laterally through the filter media and flows axially in the hollow interior (38). The filter element has an axial flow passage (56a) along the axis (40) and circumscribing the hollow interior (38) and has a flow perimeter (218) greater than the inner perimeter (34) of the filter element defined by the inner pleat tips (36), and in the preferred embodiment substantially the same as the outer perimeter (30) defined by the outer pleat tips (32), to provide axial flow (58) through the hollow interior (38) and additional axial flow (59 and 59a) through the axial ends (68) of the pleats.

Abstract: A full flow fluid filter (300, FIG. 15) has a housing (302) extending axially along an axis (304), and a pleated filter element (318) having a plurality of pleats in a closed loop annulus having an outer perimeter (320) defined by a plurality of outer pleat tips, an inner perimeter (322) defined by a plurality of inner pleat tips, and a hollow interior (324) extending along the axis. Fluid flows substantially directly axially through the filter element, with minimal bending and change of direction, minimizing flow restriction.