Dry-type air filters

Claim 2

A DRY-TYPE AIR FILTER COMPRISING MEANS DEFINING A CYCLINDRICAL CASING HAVING A SIDE WALL A CYCLINDRICAL FILTER ELEMENT MEANS MOUNTING SAID FILTER ELEMENT WITHIN SAID CASING AND BEING OF RELATIVELY LESS DIAMETER THAN SAID CASING DEFINING THEREWITH AN ANNULAR SPACING THEREBETWEEN, MEANS DEFINING THE REWARD END OF SAID CASING, MEANS DEFINING THE FORWARD END OF SAID CASING, SAID CASING HAVING A TANGENTIAL DIRTY AIR IN LET IN ITS SIDE WALL PROXIMATE ITS REARWARD END, SAID CASING ALSO HAVING A CLEAN AIR OUTLET, THE IMPROVEMENT COMPRISING A SHIELD DISPOSED INTERIORLY OF SAID CASING WITHIN SAID SPACING, BETWEEN SAID FILTER ELEMENT AND SAID DIRTY AIR INLET PROTECTING SAID FILTER ELEMENT FROM DIRECT IMPACT BY DIRTY AIR FROM SAID INLET, SAID SHIELD BEING ARCUATE IN CROSS SECTION AND AND OF REDUCED PERIPHERAL EXTENT WITH RELATION TO SAID FILTER ELEMENT EXTENDING ABOUT ONLY A PORTION THEREOF, SAID SHIELD HAVING A FORWARD END EDGE, A REARWARD END EDGE, AND FIRST AND SECOND SIDW EDGES, SAID FORWARD END EDGE, TERMINATING A LIMITED DISTANCE FORWARDLY OF SAID OPENING, SAID REARWARD END EDGE TERMINATING PROXIMATE SAID CASING REARWARD END, SAID FIRST SIDE EDGE BEING RELATIVELY REMOTE FROM SAID INLET, SAID SHIELD SECOND SIDE EDGE BEING RELATIVELY PROXIMATE SAID INLET, AN OUT-TURNED RAMP INTEGRALLY FORMED ON THE PROXIMATE SAID SECOND SIDE EDGE OF SAID SHIELD AND EXTENDING ACROSS SAID SPACING, OTHERWISE SAID SHIELD THROUGHOUT ITS EXTENT IS SPACE FROM SAID CASING SIDE WALL.

Claim 3

The improvement as defined in claim 1 and further characterized by said ramp having a forward end edge, a rearward end edge, and an outer side edge, said outer side edge contacting said casing wall throughout the length of said ramp outer side edge, said ramp having its longitudinal axis at an angle of less than 180* to the longitudinal axis of said casing, with its forward end edge located slightly forwardly of said inlet and its rearward end edge presented laterally of said inlet for deflecting dirty air impinging upon said ramp toward the inner surface of the casing for flow about the axis thereof in a helical path.

Claim 4

A dry-type air filter comprising means defining a cylindrical casing having a side wall, a cylindrical filter element, means mounting said filter element within said casing and being of relatively less diameter than said casing defining therewith an annular spacing therebetween, means defining the rearward end of said casing, means defining the forward end of said casing having a tangential dirty air inlet in its side wall proximate its rearward end, a shield disposed interiorly of said casing within said spacing, between said filter element and said dirty air inlet protecting said filter element from direct impact by dirty air from said inlet, said shield being arcuate in cross section and of reduced peripheral extent with relation to said filter element extending about only a portion thereof, said shield having a forward end edge, a rearward end edge, and first and second side edges, said forward end edge terminating a limited distance forwardly of said opening, said rearward end edge terminating proximate said casing rearward end, said first side edge being relatively remote from said inlet, said shield second side edge being relatively proximate said inlet, an out-turned ramp integrally formed on the proximate second side edge of said shield and extending across said spacing, otherwise said shield throughout its extent is spaced from said casing side wall, said ramp having a forward end edge, a rearward end edge, and an outer side edge, said outer side edge contacting said casing side wall throughout the length of said ramp outer side edge, said ramp having its longitudinal axis at an angle of less than 180* to the longitudinal axis of said casing, with its forward end edge located slightly forwardly of said inlet and its rearward end edge presented laterally of said inlet for deflecting dirty air impinging upon said ramp toward the inner surface of the casing for flow about the axis thereof in a helical path, dust collecting means provided at the forward end of said casing for receiving dirty air deflected by said ramp, said casing having a clean air outlet at its rearward end, said clean air outlet communicating with the interior of the filter element rearwardly of said shield.

Claim 5

A dry-type air filter comprising means defining a cylindrical casing having a side wall, a cylindrical filter element, means mounting said filter element within said casing and being of relatively less diameter than said casing defining therewith an annular spacing therebetween, means defining the rearward end of said casing, means defining the forward end of said casing having a tangential dirty air inlet in its side wall proximate its rearward end, a shield disposed interiorly of said casing within said spacing, between said filter element and said dirty air inlet protecting said filter element from direct impact by dirty air from said inlet, said shield being arcuate in cross section and of reduced peripheral extent with relation to said filter element extending about only a portion thereof, said shield having a forward end edge, a rearward end edge, and first and second side edges, said forward end edge terminating a limited distance forwardly of said opening, said rearward end edge terminating proximate said casing rearward end, said first side edge being relatively remote from said inlet, said shield second side edge being relatively proximate said inlet, an out-turned ramp integrally formed on the proximate second side edge of said shield and extending across said spacing, otherwise said shield throughout its extent is spaced from said casing side wall, said ramp having a forward end edge, a rearward end edge, and an outer side edge, said outer side edge contacting said casing side wall throughout the length of said ramp outer side edge, said ramp having its longitudinal axis at an angle of less than 180* to the longitudinal axis of said casing, with its forward end edge located slightly forwardly of said inlet and its rearward end edge presented laterally of said inlet for deflecting dirty air impinging upon said ramp toward the inner surface of the casing for flow about the axis thereof in a helical path, dust collecting means provided at the forward end of said casing for receiving dirty air deflected by said ramp, said casing having a clean air outlet at its rearward end, said clean air outlet communicating with the interior of the filter element rearwardly of said shield.