Phonograph pickup stylus

Claim 2

A phonograph pickup stylus comprising a conical stylus body having at least one plane cut face formed by removing material from said conical body along at least a single cut portion of the stylus body, the removed material including the conical vertex thereof and being partitioned from the remainder of the body by at least one intersecting plane inclined at a specific angle theta (less than 90) relative to the centerline axis of the body passing through the vertex, an edge line being formed at the intersection between said plane cut face and the outer conical surface of the body, the angle between tangents at two side points of said edge line near the tip part thereof being substantially equal to the dihedral angle between the opposed side walls of a record disc groove in which the stylus is placed in operation whereby said side points and the parts in the vicinity thereof contact said groove, and the radius of curvature of the edge line at the side points and the parts in the vicinity thereof being greater than the radius of an imaginary circle tangentially inscribed between the edge line at the two side points.

Claim 3

The phonograph pickup stylus as claimed in claim 1 in which at least one cut face passes through a point disposed near said vertex and on one of the side profile lines of the stylus body as viewed laterally and perpendicularly relative to the direction of its travel, said cut face also passes through a point disposed remotely from the vertex and on the other side profile line, and said edge line between said cut face and the outer conical surface of the stylus body outlines a substantially elliptical figure.

Claim 4

The phonograph pickup stylus as claimed in claim 1 in which at least one cut face passes through a point disposed near said vertex and on one of the side profile lines of the stylus body as viewed laterally and perpendicularly relative to the direction of its travel, said cut face is parallel to the other side profile line, and said edge line between said cut face and the outer conical surface of the stylus body outlines a substantially parabolic figure.

Claim 5

The phonograph pickup stylus as claimed in claim 1 in which the stylus body at least at said two side points and the parts in the vicinity thereof of said edge line is rounded along the edge line with a constant radius of curvature with centers of curvature lying in a plane perpendicular to the edge line.

Claim 6

A phonograph pickup stylus comprising a conical stylus body having two cut faces formed by removing a portion of the stylus body, the removed portion including the conical vertex thereof and being partitioned from the remainder of said body by two intersecting planes inclined at a specific angle theta (less than 90) each relative to the centerline axis of the body passing through the vertex, said two intersecting planes forming a dihedral angle therebetween at their intersection, the intersections between the two edge lines formed by said two cut faces and the edge lines at the outer conical surface of the body having a symmetrical shape with respect to said intersection between said two planes, The angle between tangents at two side points of said edge lines near the tip part thereof being substantially equal to the dihedral angle between the opposed side walls of a record disc groove in which the stylus is placed in operation whereby said side points and the parts in the vicinity thereof make contact with said groove, and the radius of curvature of the edge lines at the side points and the parts in the vicinity thereof being greater than the radius of an imaginary circle tangentially inscribed between the edge lines at the two side points.

Claim 7

A phonograph pickup stylus comprising a conical stylus body having two cut faces formed by removing a portion of the stylus body, the removed portion including the conical vertex thereof and being partitioned from the remainder of said body by two intersecting planes inclined at a specific angle theta (less than 90) each relative to the centerline axis of the body passing through the vertex, said two intersecting planes forming a dihedral angle therebetween at their intersection, the intersections between the two edge lines formed by said two cut faces and the edge lines at the outer conical surface of the body having a symmetrical shape with respect to said intersection between said two planes, The angle between tangents at two side points of said edge lines near the tip part thereof being substantially equal to the dihedral angle between the opposed side walls of a record disc groove in which the stylus is placed in operation whereby said side points and the parts in the vicinity thereof make contact with said groove, and the radius of curvature of the edge lines at the side points and the parts in the vicinity thereof being greater than the radius of an imaginary circle tangentially inscribed between the edge lines at the two side points.

Claim 8

The phonograph pickup stylus as claimed in claim 5 in which said conical stylus body has a vertex angle of 60*, and the angle between one of said two cut faces and the extrapolated extension of the other cut face is 60*, the stylus being used in operation with the centerline axis thereof maintained perpendicular to the record disc.

Claim 9

A phonograph stylus comprising an initially conical tip having a portion of the cone removed, said portion having at least one flat surface forming an elliptical conical section dividing the vertex of said cone from the stylus.

Claim 10

A phonograph stylus comprising an initially conical tip having a portion of the cone removed, said portion having at least one flat surface forming an elliptical conical section dividing the vertex of said cone from the stylus.

Claim 11

The stylus of claim 7 wherein there are two of said flat surfaces set at an angle with respect to each other so that the two edges created by the intersections of the flat surfaces with the conical surface tangentially conform to the angle made by the walls of a phonograph groove.