US2336348A - Strainer - Google Patents

Description

Dec. 7, 1943. J, B, DEMERS- 2,336,348/

STRAINER Filed Jan. 18, 1941 Patented Dec. 7, 1943 UNITED *STATES anais! ATENT OFFICE STRAINER Application January 18, 1941, Serial No. 375,012

(Cl. Zic-159) 4 Claims.

of a shell conveniently formed of pressed sheet metal and, thereupon, an inverted cup-shaped cover, of slightly smaller diameter than the inner circumference of said ledge,V is placed in coaxial position on the fabric and pushed downward so that the fabric is bent downward throughout its circumference and forms a flange extending between the inner circumference of the ledge of the shell and the outer circumference of the flange on the cover forming a substantially fluid tight joint.

Said annular ledge performs the important function of assuring that the cotton iilter disk is always centered over the strainer outlet opening, so that when the inverted cup-shaped cover is pushed downwardly, the outer annular portion of the cotton disk forms a gasket completely around the inverted cup. In strainers of the prior art which are not provided with any such annular ledge, if the cotton disk were not centered when the cup is pushed downwardly, the cotton n disk does not form a gasket completely around the cup, with the result that side leakage occurs with milk passing through without filtering. In prior art strainers, it is necessary to use a much oversized filter disk to assure that the disk always extends beyond the entire circumference of the cup the necessary amount to form a gasket around the entire cup. With the use of the centering ledge of my invention, it is possible to use smaller disks and at the same time be assured that a gasket always will be formed completely around the cup. Y

In my invention, the inverted cup-shaped covers are provide-d with a plurality of perforations, conveniently arrangedin circumferential series, to permit the passage of fluid to be strained downwardly from the shell through the perforations in the cover and out through perfor-ations in the bottom of the shell into a suitable receptacle, for instance, a milk can.

Another feature of my invention is that the bottom of the shell is pressed upwardly to form a large opening therethrough surrounded by an upturned annular supporting flange. With the use of gauze-faced cotton disks, said annular flange provides suilicient support to uphold the center of the disk. In Strainers of the prior art in which the ltering disks are upheld on an open mesh metal support or av metal grid support, such supports materially reduce the ltering area of the disk through which the milk may pass. With the use of my improved annular upturned flange, the available filtering area per square inches of cotton disk is considerably greater than with the use of any supporting means known in prior art strainers.

My invention comprises the various novel features of construction, arrangement, and method of operation hereinafter more denitely specilied. f

In said drawing, Figs. I, II, and III are respective vertical, diametrical, sectional views of circular shells, covers and strainer disks respectively different in construction, arrangement, and method of operation.

Referring to the form of my invention shown in Fig. I; the circular shell l, which is conveniently formed of pressed sheet metal, has the cylindrical portion 2 of less diameter than the upper portion of the shell and the cylindrical portion 3 of less diameter than the cylindrical portion 2; so that an annular plane ledge i is formed between said cylindrical portions.

The bottom E of said shell l is pressed upward to form a large opening 'l therethrough surrounded by the upturned annular supporting flange 8. I also nd it convenient to provide a circular series of outlet openings 9 in the bottom B of said shell i for the escape of fluid which has been strained.

The straining or filtering element H is a primarily circular plane disk of any suitable foraminous fabric, for instance, a disk formed of cotton wadding or carded cotton. Such disks may also be faced with gauze. Said disk Il is slightly smaller in its outside diameter than the inside diameter of the cylindrical portion 2 of the shell l and is laid upon the ledge 4 in coaxial relation with the shell. The cover l2 is also conveniently formed of pressed sheet metal and with a circular series of openings I3 therethrough through which iiuid may pass from the shell I. I have found it convenient to make the openings I3 vertical slots which are wider at the top than at the bottom to distribute the fluid uniformly throughout the circumference of the cover. However, they may be otherwise shaped. The

operator places said cover l2 upon the strainerA disk Il, in coaxial relation therewith, and then presses the cover down with the effect that the fabric is bent downward throughout its circumference and forms a flange I4 extending upwardly between the inner circumference of the ledge 4 and the outer circumference of the flange I5 on the cover, forming a substantially fluid tight joint.

Referring to the form of my invention shown in Fig. II; the circular shell I1, which is conveniently formed of pressed sheet metal, has the cylindrical portion I8 of less diameter than the upper portion of the shell and the cylindrical portion I9 of less diameter than the cylindrical portion I8; so that an annular plane ledge 2n is formed between said cylindrical portions.

The bottom 2I of said shell I1 has Ya large number of small outlet openings 22 for the escape of fluid which has been strained. Said openings are conveniently arranged'in circular series, but may be otherwise disposed.

The straining or filtering element 23 is a primarily circular plane disk of any suitable material. Said disk 23 is yslightly smaller in its outside diameter than the inside diameter of the cylindrical portion 4I8 of the shell I1 and is laid upon the ledge 20, in coaxial relation with the shell I1. The cover 24 is also conveniently formed of pressed sheet metal and with a circular series of openings 25 therethrough through which fluid may pass from the shell I1. I have found it convenient to make said openings 25 vertical slots wider at the top than at the bottom, but they may be otherwise shaped. The operator places said cever 24 upon the strainer disk 23, in coaxial relation therewith, and then presses the cover down with the effect that the fabric is bent downward throughout its circumference and forms a flange 23 extending upwardly between the inner circumference of the ledge 20 and the outer circumference of the flange 21 on the cover 24. I have found it convenient to provide the lower portion of the shell I1 with the reinforcing ring 28 to prevent its distortion by rough usage.

Referring to the form of my invention shown in Fig. III; the circular shell 30, which is conveniently formed of pressed sheet metal, has the cylindrical portion 3I of less diameter than the upper portion of the shell and the cylindrical portion 32 of less diameter than the cylindrical portion 3|; so that an annular plane ledge 33 is formed between said cylindrical portions.

The reinforcing ring 34 around the lower end of said shell has the inwardly turned fiange 35. The grill including a ring with a series of parallel spaced wires 36, supports the straining element 31. The fluid being strained escapes from said shell 30 through said grill.

The straining or filtering element 31 is a primarily circular plane disk of any suitable material. Said disk 31 is slightly smaller in its outside diameter than the inside diameter of the cylindrical portion 3.I of the shell 30 and is laid upon the ledge 33 in coaxial relation with said shell 30. The cover 38 is also conveniently formed of pressed sheet metal and with a circupresses the cover down with the effect that the fabric is bent downward throughout its circumference and forms a fiange 40 extending upwardly between the inner circumference of the ledge 33 and the outer circumference of the flange 4I on the cover 38.

The covers above described may be provided with handles of any desired vertical extent as indicated respectively at 42 in Fig. I, and at 43 in Fig. III.

However, I do not desire to limit myself to the precise details of construction, arrangement, or method of operation above described, as it is obvious that various modifications may be made therein without departing from the essential features of my invention, as defined in the appended claims.

I claim:

l. vA strainer as in claim 4; wherein the outlet portion of said bowl member has an inwardly upturne'd annular flange, provided with a series o f openings therethrough, adapted to support the filtering disk above the bottom of the strainer.

2. A structure as in claim 4; wherein the first named member has at the lower region thereof forarninous means for supporting the filtering `disk `intermediate of the width of the filtering disk.

3; A structure as in 'claim Ll; wherein the first nam-ed member has in the lower region thereof .grid means for supporting said filtering disk intermediate of the width of the filtering disk.

4. In a strainer; the combination of a hollow rigid bowl member; a substantially cylindrical intermediate reduced portion formed in said bowl member near the bottom thereof, said substantially cylindrical intermediate reduced portion being of slightly greater diameter than the transverse dimension of a filtering disk; a further reduced hollow outlet portion circular in crosssection at the bottom of said bowl member; an offset ledge between said intermediate reduced portion and said outlet portion, said ledge being formed in a .pl-ane at substantially right angles to the axes of said two reduced portions; an inverted cup-shaped rigid member, having a series of openings therethrough, adapted to fit into telescopic relation with the hollow outlet portion of said bowl member; a normally plane flexible foraminous filtering disk of greater dimension than said cup-shaped member and of slightly lesser transverse dimension than the inside diameter kcf said intermediate cylindrical portion, said disk extending across said outlet and with the periphery of said disk clamped between said cup-shaped member and said reduced outlet portion of said bowl member; whereby, when said filtering disk isfplaced in said strainer, said disk is centered over said outlet opening by means of said intermediate cylindrical side wall and Vsaid ledge the bottom of said bowl member, and when said disk is pushed by said cup-shaped member into telescopic relation with the Walls of said outlet portion, the margin of said disk is bent transversely and seals said bowl member and vsaid cup-shaped member into substantially fluid tightV relationship.

.ISAIE J. B. DEMERS.

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