Pierce nut fastening means and method

Claim 2

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides extending between said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug of a size and shape corresponding to that of the nut shank and forming a polygonal opening in said plate; press means for driving the nut shank first through said throat then into said slug chamber, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; and metal deforming means located in the die cavity adjacent said throat and extending across corner regions of said die cavity, to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber.

Claim 3

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank first through said throat then into said slug chamber, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; and metal deforming means located with the slug chamber, to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber, said metal deforming means comprising a plurality of impact ledges located within the slug chamber adjacent to opposite corners of the polygonal throat of the die cavity.

Claim 4

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank first through said throat then into said slug chamber, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; and metal deforming means located with the slug chamber, to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber, said metal deforming means comprising a plurality of impact ledges located within the slug chamber adjacent to opposite corners of the polygonal throat of the die cavity.

Claim 5

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of a nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank first through said throat then into said slug chamber, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate within the slug chamber, to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber and means for reducing the breadth dimensions of the slug during advancement thereof within the chamber.

Claim 6

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of a nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank first through said throat then into said slug chamber, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate within the slug chamber, to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber and means for reducing the breadth dimensions of the slug during advancement thereof within the chamber.

Claim 7

Apparatus as specified by claim 3, wherein is included means for discharge of the reduced slug through the die cavity throat subsequently to mounting of the nut upon the plate aforesaid.

Claim 8

Apparatus as specified by claim 2, wherein the slug chamber includes an upstanding dome element over which dome element the slug is deformed while undergoing advancement by said press means, to reduce the breadth dimensions of said slug.

Claim 9

Apparatus as specified by claim 5, wherein said dome element is normally fixed within said chamber, and means is provided for dislodging the slug from said dome element.

Claim 10

Apparatus as specified by claim 6, wherein the means last mentioned comprises a passageway in the dome element for directing a stream of compressed air against a face of the slug.

Claim 11

Apparatus as specified by claim 2, wherein the impact ledges of the metal deforming means are constituted by an annular edge of a cylindrical sleeve disposed within the slug chamber, said annular edge being spaced from the plate-supporting surface of the die a distance approximating the thickness of the mounting plate.

Claim 12

Apparatus as specified by claim 8, wherein the inside diameter of the sleeve at said annular edge is of a lesser dimension than the distance across two opposite corners of the polygonal throat.

Claim 13

Apparatus as specified by claim 9, wherein is included means for embossing the metal surrounding the polygonal opening of the mounting plate.

Claim 14

Apparatus as specified by claim 9, wherein said annular edge of the cylindrical sleeve rests upon the surface of a cone whose apex is located within the confines of the sleeve.

Claim 15

Apparatus as specified by claim 8, wherein the slug chamber includes an upstanding dome element over which dome element the slug is deformed while advancing into the slug chamber, to reduce the breadth dimensions of said slug.

Claim 16

Apparatus as specified by claim 12, wherein said dome element is normally fixed within said chamber, and means is provided for dislodging the slug from said dome element and said chamber.

Claim 17

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank through said throat and into said slug chamber and with disposition of the nut head in abutment against once face of the plate; and metal deforming means comprising shoulders at spaced corner positions in said cavity to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber.

Claim 18

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank through said throat and into said slug chamber and with disposition of the nut head in abutment against once face of the plate; and metal deforming means comprising shoulders at spaced corner positions in said cavity to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber.

Claim 19

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank through said throat and into said slug chamber to excise the slug, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; metal deforming means to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the pLate as said shank advances into the slug chamber, and means for deforming the slug area of the plate to reduce the breadth dimensions of said slug prior to advancement of the slug into said slug chamber.

Claim 20

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank through said throat and into said slug chamber to excise the slug, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; metal deforming means to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the pLate as said shank advances into the slug chamber, and means for deforming the slug area of the plate to reduce the breadth dimensions of said slug prior to advancement of the slug into said slug chamber.

Claim 21

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank through said throat and into said slug chamber to excise the slug, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; metal deforming means to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber, and means for deforming the slug, comprising a plunger having a projectile end, and means for driving said plunger end forcefully against the slug area of the plate to convex said slug area substantially simultaneously with excision of the slug.

Claim 22

Apparatus for securing upon a mounting plate a pierce nut having a head, and a polygonal shank having sides intersecting to provide corners, and cutting edges on said sides intermediate said corners, said apparatus comprising: a die having a plate-supporting surface provided with a die cavity, said cavity having a throat and a communicating slug chamber, said throat having the polygonal shape and approximate size of the nut shank, whereby the cutting edges of the polygonal nut shank are drivable through the plate and into said throat for excising a polygonal slug and forming a polygonal opening in said plate; press means for driving the nut shank through said throat and into said slug chamber to excise the slug, with advancement of the slug into said slug chamber and with disposition of the nut head in abutment against one face of the plate; metal deforming means to engage and displace the metal of the corners of the nut shank firmly against the remaining face of the plate as said shank advances into the slug chamber, and means for deforming the slug, comprising a plunger having a projectile end, and means for driving said plunger end forcefully against the slug area of the plate to convex said slug area substantially simultaneously with excision of the slug.

Claim 23

Apparatus as specified by claim 16, wherein said slug chamber has a through opening for discharge of the slug in the direction of advancement of said plunger.

Claim 24

Apparatus as specified by claim 14, wherein said plunger includes a plunger head, and said press means includes a reciprocable driver movable against said head to advance the plunger; a member to overlie the nut; and yielding means intermediate said plunger head and said member, to transmit a portion only of the plunger head advancement to said member overlying the nut.

Claim 25

Apparatus as specified by claim 18, wherein said yielding means comprises a mass of resilient rubber like material.