IP Library Granted Patent US 12667799
Granted Patent B2
US 12667799 · App. 18/691,344 · Granted Jun 30, 2026

In-line strainer

Inventor: Hideo Okuno (Osaka, JP)
Assignee: Three-M Industry Co., Ltd.
B01D35/023B01D29/114
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Quick Facts
Patent No.
US 12667799
App. No.
18/691,344
Granted
Jun 30, 2026
Kind
B2
Abstract

Provided is an in-line strainer capable of more reliably preventing the concentrated adhesion and accumulation of solid foreign matter or the like on a portion of a screen. In an in-line strainer according to the present invention, a housing 9 includes a cylinder wall 24 that is formed in a hollow cylindrical shape and extends in the vertical direction, and a top wall 25 that closes an upper end of the cylinder wall 24 . The filter chamber 8 is divided into a primary flow path chamber 39 formed on the upper side and communicating with an inflow port 6 and a secondary flow path chamber 40 formed on the lower side and communicating with an outflow port 7 , and a through-hole 38 is provided in an open manner between the two chambers 39 and 40 . The screen 10 includes a filter cylinder 33 that is formed in a vertically long hollow cylindrical shape having openings at upper and lower ends, and a bottom lid 34 that closes the lower-end opening of the filter cylinder 33 , and an introduction port 36 that allows introduction of liquid is formed at the upper end of the filter cylinder 33 . The screen 10 is disposed in the filter chamber 8 , in an orientation such that the introduction port 36 faces the through-hole 38 , and the outflow port 7 is provided in an open manner in the cylinder wall 24 that faces the lower half of the filter cylinder 33.

Claims (34)

1 . A filtration device comprising:

a housing ( 9 ) including

a filter chamber ( 8 ) extending vertically and formed by a hollow cylindrical wall ( 24 ) and a top wall ( 25 ) closing an open upper end of the hollow cylindrical wall ( 24 );

a hollow cylindrical pressing shaft ( 55 ) extending into the filter chamber ( 8 ) from the top wall ( 25 );

an inflow port ( 6 ) through which liquid to be filtered flows in; and

an outflow port ( 7 ) formed partially on a left rear circumferential surface of the hollow cylindrical wall ( 24 ) through which filtered liquid flows out;

an inflow pipe ( 11 ) provided on a left side of the housing and in fluid communication with the inflow port ( 6 );

an outflow pipe ( 12 ) provided on a right side of the housing and in fluid communication with the outflow port ( 7 );

a hollow frustoconical screen element ( 10 ) having a frustoconically shaped screen wall ( 33 ) defining a hollow prefilt cavity with an upper open end and a lower open end, disposed in the filter chamber ( 8 ) to filter liquid flowing in from the inflow port ( 6 );

a pressing plate ( 47 ) having at least one liquid passage hole ( 54 ) extending therethrough, dividing the filter chamber ( 8 ) into an upper primary flow path chamber ( 39 ) in fluid communication with the inflow port ( 6 ) and a lower secondary flow path chamber ( 40 ) in fluid communication with the outflow port ( 7 );

a through-hole ( 38 ) provided between the upper primary flow path chamber ( 39 ) and the lower secondary flow path chamber ( 40 ), the hollow frustoconical screen element ( 10 ) extending through the through-hole ( 38 );

a pressure spring ( 48 ) compressively extending between a bottom end face surface ( 99 ) of the hollow cylindrical pressing shaft ( 55 ) and the pressing plate ( 47 ), such that a biasing force is exerted on the pressing plate ( 47 ) downwardly to hold the hollow frustoconical screen element ( 10 ) in place;

a connecting pipe ( 44 ) having a first end in fluid communication with the outflow port ( 7 ) and a second end in fluid communication with the outflow pipe ( 12 ), the connecting pipe ( 44 ) being protrudingly formed on an outer circumferential surface of a rear half of the hollow cylindrical wall ( 24 ) and extending obliquely upward while winding around the outer circumferential surface of the hollow cylindrical wall ( 24 ); and

a bottom lid ( 34 ) closing the lower open end of the hollow frustoconical screen element ( 10 ).

2 . The filtration device as recited in claim 1 , further comprising:

an annular fixing seat ( 41 ) peripherally cantilevered inwardly from an inner peripheral surface of the hollow cylinder wall ( 24 ), an inner side of the fixing seat ( 41 ) defining the through-hole ( 38 ).

3 . The filtration device as recited in claim 1 , further comprising:

a fixing ring ( 35 ) is received by the annular fixing seat ( 41 ), and disposed beneath the pressing plate ( 47 ).

4 . The filtration device as recited in claim 1 , further comprising:

a cleaning brush ( 58 ) rotatably operable by a handle ( 62 ) that is disposed above the upper outside of the housing ( 9 ); and

a handle shaft ( 63 ) extending coaxially with an upper end of a brush shaft ( 59 ) through an inside of the pressure spring ( 48 ), an interior of the cylinder of the pressing shaft ( 55 ), a shaft hole ( 65 ) extending through the top wall ( 25 ), and operably connected to the handle ( 62 ).

5 . The filtration device as recited in claim 1 , wherein the pressure spring ( 48 ) is a torsion coil spring.

6 . The filtration device as recited in claim 1 , wherein:

an extension direction of the cylinder wall ( 24 ) is defined as a cylinder axis (HC) and an extension direction of the frustoconically shaped screen wall ( 33 ) is defined as a cylinder axis (SC), and both axes (HC, SC) coincide with each other, and

a swirling protrusion ( 43 ) that slopes downward in a spiral shape is provided on an inner peripheral surface of the cylinder wall ( 24 ) that defines the secondary flow path chamber ( 40 ).

7 . The filtration device as recited in claim 1 , further comprising:

a first cylindrical boss ( 49 ) extending from a lower surface of the bottom lid ( 34 ); and

a second cylindrical boss ( 50 ) provided on an upper surface of the bottom wall ( 26 ) of the cylinder wall ( 24 ), the first cylindrical boss ( 49 ) being fitted within the second cylindrical boss ( 50 ).

8 . The filtration device as recited in claim 7 , further comprising:

a lower discharge flow path ( 75 ) defined by a vertical through-hole that extends from an upper surface of the second boss ( 50 ) to a lower surface of a valve boss ( 77 ) protruding from a lower surface of a bottom wall ( 26 ) of the housing ( 9 ).

9 . The filtration device as recited in claim 8 , further comprising:

a drain valve ( 76 ) threadably received within the valve boss ( 77 ), including an inner valve body operable by manually turning a lever ( 78 ).

10 . The filtration device as recited in claim 1 , wherein, the pressing plate ( 47 ) includes an inner ring ( 51 ) that receives the pressure spring ( 48 ), an outer ring ( 52 ) that engages the fixing ring ( 35 ), and a plurality of bridge pieces ( 53 ) that are radially provided and interconnect the inner ring ( 51 ) and the outer ring ( 52 ).

11 . The filtration device as recited in claim 10 , wherein, the inner ring ( 51 ) and the outer ring ( 52 ) are concentric ring bodies, and the pressing plate ( 47 ) is formed with a plurality of through liquid passage holes ( 54 ), which are surrounded by the inner ( 51 ) and outer ring ( 52 ) and adjacent bridge pieces ( 53 ), wherein, liquid in the primary flow path chamber ( 39 ) passes through the plurality of liquid passage holes ( 54 ) to the hollow interior of the frustoconically shaped screen wall ( 33 ) through the introduction port ( 36 ).