Method of manufacturing drawn cup bearing races with crowned pathways

Claim 2

The process of manufacturing a drawn cup cylindrical bearing race having a convexly crowned internal surface comprising the steps of: forming a preform cup from a flat circular blank, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall from said corner, said drawing entailing sufficient force to produce a stretching of the side wall of the cup so that a portion of the side wall increases in thickness from the corner of the cup and has an internal inwardly tapering surface extending from the corner to a point beyond a mid point of a crowned internal surface to be formed on the side wall, and reforming said preform cup with a die ring and a punch having a concavely tapered nose into a cup with a crowned internal surface comprising a lower half and an upper half, said concavely tapered nose being radially spaced from said lower half and forming said upper half cooperatively with said die ring during said reforming operation.

Claim 3

The process as defined in claim 1 further including the step of buckling said side wall inwardly slightly by applying an axial load to said side wall without any internal support for said side wall whereby the crown on said internal surface is accentuated.

Claim 4

The process of manufacturing a thick walled, drawn cup bearing race having a crowned pathway comprising the steps of: forming a flat bottomed preform cup from a flat circular blank with a die ring and a substantially flat nosed punch, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall from said corner and entailing sufficient force to cause a stretching of the side wall of the cup so that it has a thickness which increases from said corner of the cup to a point well beyond the mid point of the side wall, reforming said preform cup with a die ring of smaller diameter than said first die ring and a punch having a lower concavely tapered forming surface terminating in a substantially flat bottom into a deeper bearing cup of reduced diameter and with a crowned internal surface, and applying an axial load to said side wall while maintaining lateral support only on the outside thereof to buckle said side wall slightly and increase the crown on said internal surface.

Claim 5

The process of manufacturing a thick walled, drawn cup bearing race having a crowned pathway comprising the steps of: forming a flat bottomed preform cup from a flat circular blank with a die ring and a substantially flat nosed punch, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall from said corner and entailing sufficient force to cause a stretching of the side wall of the cup so that it has a thickness which increases from said corner of the cup to a point well beyond the mid point of the side wall, reforming said preform cup with a die ring of smaller diameter than said first die ring and a punch having a lower concavely tapered forming surface terminating in a substantially flat bottom into a deeper bearing cup of reduced diameter and with a crowned internal surface, and applying an axial load to said side wall while maintaining lateral support only on the outside thereof to buckle said side wall slightly and increase the crown on said internal surface.

Claim 6

The process as defined in claim 3 including forming a thinned axial flange on said side wall simultaneously with reforming said preform cup, and bending said thinned axial flange into a radial flange to provide a bearing cup with two integral end walls, said axial load being applied during said bending of said axial flange.

Claim 7

The process of manufacturing a thick walled, drawn cup bearing race having a crowned pathway comprising the steps of: forming a first flat bottomed preform cup from a flat circular blank with a die ring and a substantially flat nosed punch, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall and entailing sufficient force to cause a stretching of the side wall of the cup so that it has a thickness which increases from the corner of the cup to a point well beyond the mid point of the side wall, drawing a second deeper preform cup of reduced diameter with a second die ring of smaller diameter than said first die ring and a substantially flat nosed punch, said drawing further stretching said side wall and reducing its thickness while maintaining an increasing thickness from the corner of the cup to a point well beyond the mid point of the side wall, and reforming said second preform cup with a die ring of smaller diameter than said second die ring and a punch having a lower concavely tapered forming surface terminating in a substantially flat bottom into a deeper bearing cup of still further reduced diameter and maximum thickness with a crowned internal surface.

Claim 8

The process of manufacturing a thick walled, drawn cup bearing race having a crowned pathway comprising the steps of: forming a first flat bottomed preform cup from a flat circular blank with a die ring and a substantially flat nosed punch, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall and entailing sufficient force to cause a stretching of the side wall of the cup so that it has a thickness which increases from the corner of the cup to a point well beyond the mid point of the side wall, drawing a second deeper preform cup of reduced diameter with a second die ring of smaller diameter than said first die ring and a substantially flat nosed punch, said drawing further stretching said side wall and reducing its thickness while maintaining an increasing thickness from the corner of the cup to a point well beyond the mid point of the side wall, and reforming said second preform cup with a die ring of smaller diameter than said second die ring and a punch having a lower concavely tapered forming surface terminating in a substantially flat bottom into a deeper bearing cup of still further reduced diameter and maximum thickness with a crowned internal surface.

Claim 9

The process as defined in claim 5 including forming a thinned axial flange on said side wall while reforming said second preform cup, and progressively bending said thinned axial flange into a radial flange to provide a bearing cup with two integral radial end walls, said progressive bending being performed without any internal support for said side wall whereby said side is buckled slightly accentuating the crown on said internal surface.

Claim 10

The process of manufacturing a thick walled, drawn cup bearing race having a crowned pathway and integral radial walls comprising the steps of: Forming a first flat bottomed preform cup from a flat circular blank with a die ring and a substantially flat nosed punch, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall and entailing sufficient force so that said side wall increases in thickness from the corner of the cup to a point well beyond the mid point of the side wall, drawing a second deeper preform cup of reduced diameter with a second die ring of smaller diameter than said first die ring and a substantially flat nosed punch, said drawing stretching said side wall and reducing its thickness while maintaining an increasing thickness from the corner of the cup to a point well beyond the mid point of the side wall, reforming said second preform cup with a die ring of smaller diameter than said second die ring and a multiple surfaced punch having a lower concavely tapered forming surface terminating in a substantially flat bottom, a juxtaposed ring having a forming surface of larger diameter than the maximum diameter of said concavely tapered forming surface and a scoring edge immediately adjacent the upper end of said ring into a deeper bearing cup of reduced diameter and maximum thickness with a crowned internal surface, a thinned axial flange adjacent its open end and a score line on the interior surface of the thinned flange, severing the open end of said third cup at said score line, and progressively bending said thinned axial flange into a radial flange without any internal lateral support for said side wall whereby a column effect is produced on said side wall hollowing its external surface slightly and increasing the crown on its internal surface.

Claim 11

The process of manufacturing a thick walled, drawn cup bearing race having a crowned pathway and integral radial walls comprising the steps of: Forming a first flat bottomed preform cup from a flat circular blank with a die ring and a substantially flat nosed punch, said forming involving cupping of a bottom wall with a small radius corner and drawing of a side wall and entailing sufficient force so that said side wall increases in thickness from the corner of the cup to a point well beyond the mid point of the side wall, drawing a second deeper preform cup of reduced diameter with a second die ring of smaller diameter than said first die ring and a substantially flat nosed punch, said drawing stretching said side wall and reducing its thickness while maintaining an increasing thickness from the corner of the cup to a point well beyond the mid point of the side wall, reforming said second preform cup with a die ring of smaller diameter than said second die ring and a multiple surfaced punch having a lower concavely tapered forming surface terminating in a substantially flat bottom, a juxtaposed ring having a forming surface of larger diameter than the maximum diameter of said concavely tapered forming surface and a scoring edge immediately adjacent the upper end of said ring into a deeper bearing cup of reduced diameter and maximum thickness with a crowned internal surface, a thinned axial flange adjacent its open end and a score line on the interior surface of the thinned flange, severing the open end of said third cup at said score line, and progressively bending said thinned axial flange into a radial flange without any internal lateral support for said side wall whereby a column effect is produced on said side wall hollowing its external surface slightly and increasing the crown on its internal surface.