Hopper structure for pneumatically unloading bulk materials

Claim 1

A BOTTOM OUTLET STRUCTURE ADAPTED TO BE SECURED BENEATH THE BOTTOM OUTLET OF A HOPPER STRUCTURE FOR THE PNEUMATIC DISCHARGE OF PARTICULATE MATERIAL AND COMPRISING A GENERALLY RECTANGULAR GATE SLIDABLE BACK AND FORTH IN OPPOSITE DIRECTIONS BETWEEN OPEN AND CLOSED POSITIONS RELATIVE TO SAID BOTTOM OUTLET, A GENERALLY RECTANGULAR SUPPORTING FRAME EXTENDING DOWNWARDLY FROM THE GATE ON WHICH THE GATE IS SUPPORTED FOR SLIDING MOVEMENT, A BOTTOM COVER BENEATH THE GATE EXTENDING IN A PLANE GENERALLY PARALLEL TO THE PLANE OF SAID GATE AND FORMING WITH THE FRAME AND GATE AN ENCLOSED SPACE OF A UNIFORM CROSSSECTIONAL AREA IN THE CLOSED POSITION OF THE GATE INTO WHICH THE MATERIAL MOVES UPON OPENING OF THE GATE, SAID GATE AND SAID BOTTOM COVER BEING SPACED FROM EACH OTHER A MAXIMUM DISTANCE NOT SUBSTANTIALLY EXCEEDING TWO INCHES, THE EXPOSED EDGE OF THE GATE UPON OPENING FORMING AN ENTRANCE RESTRICTION TO THE SPACE BETWEEN THE GATE AND COVER, AN ELONGATE PNEUMATIC CONDUIT BELOW THE GATE EXTENDING IN A DIRECTION GENERALLY TRANSVERSELY OF THE SLIDING MOVEMENT OF THE GATE FOR SUBSTANTIALLY THE ENTIRE LENGTH OF THE GATE, AND MEANS FORMING A MATERIAL PASSAGEWAY BETWEEN THE ENCLOSED SPACE AND THE CONDUIT FOR REMOVING THE PARTICULATE MATERIAL, SAID PASSAGEWAY BEING EFFECTIVELY POSITIONED ALONG SUBSTANTIALLY THE ENTIRE LENGTH OF THE GATE TO PERMIT THE DISCHARGE OF MATERIAL FROM ACROSS THE ENTIRE SURFACE OF THE COVER AND ALONG THE LENGTH OF THE GATE WHEREBY A RELATIVELY HIGH VELOCITY AIRSTREAM IS FORMED AT SAID RESTRICTION AND THE PARTICULATE MATERIAL MOVES FROM THE ENCLOSED SPACE TO THE CONDUIT FOR PNEUMATIC DISCHARGE.