Filter constructed of metallic material

Claim 1

A filter for removing entrained matter from a flowing material comprising a frame of rigid construction and of a configuration to provide structural support around the marginal edges of a filter element encased therein, said filter element having an inner core of metallic filtering composition and arranged to preclude passage of the entrained matter, outer coverings providing a pervious sheath affixed upon and overlying either side of the inner core and furnishing rigidity to the filter element, the cutting of the filter element into desired shapes compressing the severed edges of the inner core and contiguous outer coverings into a pressure-boNded edge that retains its integrity when separated from its frame, said filter element including the inner core and outer coverings being corrugated to increase its surface area exposure to the flowing material, said outer coverings of the filter element being formed from expanded metal thereby enhancing its rigidity allowing unencumbered movement of the flowing material therethrough, the inner core of metallic filtering composition comprising multiple layers of metallic material, said layers of metallic material being of a lesser thickness than the expanded metal forming the outer covering of the filter element, said frame providing support around the filter element being formed having a web portion that shields the rough marginal pressure-bonded edges of the inner core and outer coverings, flange portions bent integrally from said web portions and providing confinement for said filter element, and a rivet means connecting the two free ends of the integral frame together at one corner, the remaining corners of said frame being of integral construction.