Filter, strainer, and the like

June 22, 1937. f. o. l. chorlton 2,084,433

FILTER, STRAINER, AND THE .LIKE

Filed Oct. 12, 1935

<img file="US2084433A_D0001.tif" />

Patented June 22, 1937

2,084,433

UNITED STATES PATENT OFFICE

2,084,433 FILTER, STRAINER, AND THE LIKE Frank Oscar Levi Chorlton, Bury, England Application October 12, 1935, Serial No. 44,794 In Great Britain October 27,1934 6 Claims. (Cl. 210—169)

This invention relates to filters or strainers, and more particularly to filters or strainers for separating very fine solid particles from oil.

I have illustrated my invention in the accom5 panying drawing, in which:—

Figs. 1 and 2 show a cage construction suitable for use in that type of filter in which the cage on which the wire is wound is fixed in locating seatings in the filter casing so that the filtering' 10 medium is Interposed between the inlet and the outlet;

Fig. 1 being a sectional elevation on the line I—I of Fig. 2; and

Fig. 2 a plan, the left-hand half showing the 15 casing and cover in medial section, and the righthand half showing the casing and cover in medial section and also showing the cage in section on the line II—H of Fig. 1.

Fig. 3 is an elevation of a rotatable filtering ₂₀ unit showing a method of cleaning.

Figs. 4 to 11 illustrate cross-sections of wire which may be employed in carrying out the invention.

Fig. 12 illustrates to a considerable enlarged 25 scale a fragmentary section on the plane XU— XU of Fig. 1 as shown to a smaller scale at x of Fig. 2, and

Figs. 13 and 14 are views similar to Fig. 12 and show grooves modified to suit wires of semi30 circular and trapezoidal shape.

Referring first to Figs. 1 and 2;—

A is a cage or former comprising a cylindrical portion al having externally projecting longitudinally disposed ribs a2, forming water-ways 35 a3; at opposite ends the ribs a2 are connected by flanges aA which fit with suitable jointing, in seatings bl and b2 of the filter casing B. In the outer faces a6 of the ribs a2 which are of cylindrical configuration, grooves are cut which 40 form Interrupted portions of a helical groove running from end to end of the cage, the pitch of which is slightly greater than the maximum transverse dimensions of the wire employed; if a wire of triangular cross-section (as shown in 45 Fig. 4) is employed, a V-shaped groove (as shown in Fig. 12) would be cut, the depth of the groove being less than the distance from the apex of the triangle (Fig. 4) to the base thereof; a portion of the wire winding is shown at C; the ends of 50 the wire are suitably secured and the cage is retained in any suitable manner in its seatings bl and b2 across the water-way of the filter, the arrangement being such that liquid can pass from the inlet part b3 of the filter to the outlet part 55 bS through the filtering medium only; in Figs.

and 2 the flow of the water to be filtered is inwardly through the helical interstices between the convolutions of the wire, the water passing to the several longitudinal water-ways a3 and thence either directly through the openings a5 to 5 the main outlet b5, or to the recess b4 and thence to the outlet b5 through the interior of the cage.

Referring to Fig. 3;—

The arrangement is similar to that already de- 10 scribed except that the cake or former A' is rotatably mounted in the casing B'; the former A' is provided with interior teeth a20 with which a wheel G engages; the wheel G is mounted on a spindfe gt mounted in the casing A, and is adapt- 15 ed to be rotated by any suitable means, for example by an external handle on the spindle p l or by power, and a brush H is mounted on a spindle 7zl in the casing in contact with the filtering medium, whereby when the cage A' is rotated the ₂o filtering medium is cleansed from dirt or other matter adhering to the outside.

The filtering medium formed of wires of sections shown in Figs. 4 to 11 may be employed, the shape of the helical groove being modified as ₂s shown for example in Figs. 12 and 13.

Of the sections of wire given by way of example in Figs. 4 to 11, the wires shown in Figs. 4, 5, 7, 8 and 11 are suitable for those cases in which the grooves in the ribs on which the wires are wound ₃₀are adapted to take the apex or narrowest part ci of the section, as in Figs. 12, 13 and 14.

In the cases of wires of the sections shown in Figs. 4, 5 and 8 the surface presented to the flow of liquid to be filtered is practically the plain 35 cylindrical surface formed by the aligning faces c2 of the base of the section; in Figs. 7 and 11 the surfaces on each side of the entrance to the helical passage-way form a re-entrant angle which is found to be of advantage in some cases. 40

The sections shown in Figs. 6, 9 and 10 are suitable for use when the grooves in the ribs are adapted to take the shaped base part c4 of the section, for example, in Figs. 6 and 9 the wire could be wound in helical grooves of circular 45 cross-section after the manner shown in Fig. 13, the radius of curvature being considerably increased to agree with that of c4 of Figs. 6 and 9, and the depth of groove considerably diminished; similarly the wire of Fig. 10 could be 50 wound in helical grooves of triangular cross-section as in Fig. 12, the angle between the rides of the grooves being an obtuse angle as at c4 Fig. 10 and much shallower than that shown in

Fig. 12. 55

9,084,483

The bases c4 (Figs. 6, 9 and 10) are In the construction last described on the entrance side to the helical groove, the flow in this case being outwardly through the wire-wound filtering me₅ dium; the radius of curvature of the sides of the base c4 of Figs. 6 and 9 is therefore made comparatively great, and the angle between the two . sides of the base c4 in Fig. 10 is made very obtuse, in order to prevent any wedging action tak₁₀ ing place which would tend to clog the entrance to the helical passage-ways.

The configuration of the unit is above referred to as approximately cylindrical but obviously the wire-wound helix is not truly cylindrical but po15 lygonal, and where desired the body part al of the cage A may be made polygonal.