Pierce nut

Claim 2

A pierce nut for installation without distortion in a nonapertured plate comprising a nut body and an integral polygonal pilot projection extending axially from one end face of said nut body, said pilot projection having a free end face extending transversely of the axis of said nut and peripheral side surface extending between said free end face and said one end face of said nut body, said pilot projection serving as a punch to form an opening in the plate to which said nut is to be secured when forcing the nut into said plate with said free end face in engagement with one side of said plate, said pilot projection peripheral side surfaces having an undercut formed in the side surface thereof and adapted to be engaged by an edge portion of the opening formed in the metal plate, the free end face of the pilot projection surrounded by a relatively massive piercing shoulder extending from said end face, toward said undercut, substantially parallel to said nut axis and overhanging said undercut, said pilot projection being centrally disposed on said nut body so that the nut body extends laterally outwardly on all sides from the side surfaces of said pilot projection and said one end face of said nut body forms a contact surface spaced from and extending circumferentially around said polot projection; said nut body having a substantially continuous groove formed in said one end face and said groove having a bottom wall merging into the pilot projection undercut and extending laterally outwardly beyond the projection of said pilot shoulder, so that the portion of the plate filling said groove is contiguous with the plate portion filling said undercut inwardly of the overhanging portions of said pilot projection.

Claim 3

A pierce nut as defined in claim 1, wherein the nut body groove is also polygonal and continuous about the circumference of the pilot projection to merge continuously into said undercut.

Claim 4

A Pierce nut for installation without distortion in a non-apertured plate comprising a relatively massive nut body surmounted by a reduced polygonal pilot projection located centrally of said nut body, both said nut body and said reduced pilot projection being symmetrical about a vertical axis and both being traversed by a tapped hole concentric with said axis, said pilot projection having a planar end piercing face normal to said axis surrounded by a relatively massive piercing shoulder and said nut body having a planar stop shoulder also normal to said axis and located in axially spaced relation to said planar end face, said pilot projection having peripheral side surfaces joining said planar end face to said stop shoulder, said pilot projection serving as a punch to form an opening in said plate to which said nut is to be secured upon forcing the nut into said plate with the planar end face in engagement with one side of said plate, said stop shoulder then abutting the one side of said plate with the pilot projection peripheral side surfaces adapted to be engaged by an edge portion of the opening formed in the metal plate, said piercing shoulder extending from said end face substantially parallel to said nut axis and terminating in an undercut formed around the pilot projection and the planar stop shoulder of said nut body having a substantially continuous groove formed in the surface thereof engaging the plate and surrounding said pilot projection, said groove having a bottom wall extending beneath said piercing shoulder and laterally beyond the projection of said piercing shoulder, and said undercut and said groov merging into one another at a location radially intermediate the peripheral edge of said end piercing face and axially within the confines of said nut body.

Claim 5

A Pierce nut for installation without distortion in a non-apertured plate comprising a relatively massive nut body surmounted by a reduced polygonal pilot projection located centrally of said nut body, both said nut body and said reduced pilot projection being symmetrical about a vertical axis and both being traversed by a tapped hole concentric with said axis, said pilot projection having a planar end piercing face normal to said axis surrounded by a relatively massive piercing shoulder and said nut body having a planar stop shoulder also normal to said axis and located in axially spaced relation to said planar end face, said pilot projection having peripheral side surfaces joining said planar end face to said stop shoulder, said pilot projection serving as a punch to form an opening in said plate to which said nut is to be secured upon forcing the nut into said plate with the planar end face in engagement with one side of said plate, said stop shoulder then abutting the one side of said plate with the pilot projection peripheral side surfaces adapted to be engaged by an edge portion of the opening formed in the metal plate, said piercing shoulder extending from said end face substantially parallel to said nut axis and terminating in an undercut formed around the pilot projection and the planar stop shoulder of said nut body having a substantially continuous groove formed in the surface thereof engaging the plate and surrounding said pilot projection, said groove having a bottom wall extending beneath said piercing shoulder and laterally beyond the projection of said piercing shoulder, and said undercut and said groov merging into one another at a location radially intermediate the peripheral edge of said end piercing face and axially within the confines of said nut body.

Claim 6

Pierce nut comprising a tapped nut body and an integral tapped attachment member projecting axially from one end face of said nut body and having a free end face extending transversely of the axis of said nut and lateral surfaces extending between said free end face and said one end face of saie nut body, said attachment member serving as a punch to form an opening in a metal plate to which said nut is to be secured when forcing the nut into said plate with said free end face in engagement with one side of said plate, said attachment member having in at least some of said lateral surfaces an undercut recess adapted to be engaged by an edge portion of the opening formed in the metal plate, wherein the improvement comprises the combination of the following features: a. said attachment member in all phases normal to the axis of said nut being substantially square with straight sides; b. the corners of said attachment member joining adjacent straight sides being rounded off in the plane normal to the axis of said nut; c. all of said lateral surfaces sides of said attachment member having the undercut recess therein forming a continuous recess about said attachment member; d. said attachment member being centrally disposed on said nut body which in a plane normal to the axis of saie nut extends laterally outwardly on all sides from the lateral surfaces of said attachment member so that said one end face of said nut body forms an unbroken contact surface spaced from and extending circumferentially around said attachment member; e. said nut body has a depression running circumferentially around said one end face and said depression adjoins said attachment member and said undercut recess and has a configuration in a plane normal to the axis of said nut closely similar to the outer contour of the attachment member in a plane parallel thereto having four substantially straight sides and with rounded corners between adjacent sides; f. the radially outer surface of said depression sloping inwardly relative to the axis of the nut body from said one end face thereof to a transverse bottom surface which joins the side surface of said undercut recess; g. said lateral surfaces of said attachment member tapering outwardly from said free end surface toward said nut body to a smooth rounded portion and then tapering inwardly to define in part said undercut recess and said outwardly tapering surfaces amounting to about 10-60 percent of the total axial dimension of said attachment member; and h. said tapering surfaces merging smoothly with the undercut recess in said side surface.

Claim 7

Pierce nut comprising a tapped nut body and an integral tapped attachment member projecting axially from one end face of said nut body and having a free end face extending transversely of the axis of said nut and lateral surfaces extending between said free end face and said one end face of saie nut body, said attachment member serving as a punch to form an opening in a metal plate to which said nut is to be secured when forcing the nut into said plate with said free end face in engagement with one side of said plate, said attachment member having in at least some of said lateral surfaces an undercut recess adapted to be engaged by an edge portion of the opening formed in the metal plate, wherein the improvement comprises the combination of the following features: a. said attachment member in all phases normal to the axis of said nut being substantially square with straight sides; b. the corners of said attachment member joining adjacent straight sides being rounded off in the plane normal to the axis of said nut; c. all of said lateral surfaces sides of said attachment member having the undercut recess therein forming a continuous recess about said attachment member; d. said attachment member being centrally disposed on said nut body which in a plane normal to the axis of saie nut extends laterally outwardly on all sides from the lateral surfaces of said attachment member so that said one end face of said nut body forms an unbroken contact surface spaced from and extending circumferentially around said attachment member; e. said nut body has a depression running circumferentially around said one end face and said depression adjoins said attachment member and said undercut recess and has a configuration in a plane normal to the axis of said nut closely similar to the outer contour of the attachment member in a plane parallel thereto having four substantially straight sides and with rounded corners between adjacent sides; f. the radially outer surface of said depression sloping inwardly relative to the axis of the nut body from said one end face thereof to a transverse bottom surface which joins the side surface of said undercut recess; g. said lateral surfaces of said attachment member tapering outwardly from said free end surface toward said nut body to a smooth rounded portion and then tapering inwardly to define in part said undercut recess and said outwardly tapering surfaces amounting to about 10-60 percent of the total axial dimension of said attachment member; and h. said tapering surfaces merging smoothly with the undercut recess in said side surface.

Claim 8

Pierce nut, as set forth in claim 4, characterized therein that the angle of the tapering portions of said lateral surfaces being between 1* and 20* relative to the axis of said nut.