Fastener

Claim 1

A DEVICE HAVING SHEET METAL ATTACHMENT MEANS MADE OF SPRINGABLE MATERIAL COMPRISING, A HEAD, A HOLLOW STEM EXTENDING FROM SAID HEAD AND HAVING AN OPENING EXTENDING THERETHROUGH BETWEEN TWO OPPOSITE SIDES THEREOF AND CLOSED AT THE END PORTION THEREOF, AND PAIRED TANGS SUPPORTED ON SAID END PORTIONS, SAID END PORTION AND SAID TANGS BEING RESILIENT, AND SAID TANGS HAVING THE GREATER PORTIONS THEREOF LOCATED WITHIN SAID STEM OPENING AN HAVING THEIR SIDES SUBSTANTIALLY RADIAL WITH RESPECT TO THE STEM AXIS, AND EACH OF A PAIR OF SAID TANGS EXTENDING OUTWARDLY FROM SAID OPENING AND OPPOSITELY TO THE OTHER OF SAID PAIR OF TANGS, SAID TANGS HAVING EXTENDING SIDE EDGES, EACH OF SAID SIDE EDGES HAVING PAIRED OPPOSED LEADING AND FOLLOWING OPPOSITELY ANGLING CAMMING SURFACES MEETING AT A RADIAL HIGH POINT MIDWAY IN THE TANG SIDE EDGES THEREOF; SAID STEM CLOSED END PORTION BEING FIRST INSERTABLE IN A SHEET METAL OPENING WITH SAID TANGS LEADING CAMMING SIDE EDGES ON THE OPPOSITE SIDES OF SAID STEMS ENGAGING THE SIDE WALLS OF THE SHEET METAL OPENING AND COMPRESSING SAME, SO AS TO SPRING LOAD SAID TANGS, SAID SPRING LOAD ON SAID TANGS SPRINGING SAID STEM END PORTION IN OPPOSITE DIRECTIONS, WHEREUPON, SAID RADIALLY HIGH POINTS OF SAID TANGS PASSING THE SIDE WALLS OF SAID OPENING, THE SPRING LOADED TANGS FOLLOWING CAM SURFACES PRESS OUTWARDLY AGAINST THE SHEET MATERIAL OPENING SIDE WALLS, CAMMING SAID STEM FURTHET THROUGH IN AN AXIAL DIRECTION, SO AS TO PULL SAID HEAD AGAINST THE OPPOSITE SIDE OF THE SHEET METAL IN ABUTTING RELATIONSHIP THERETO, AND TO ATTACH SAID DEVICE TO THE SHEET METAL.