Allen W Perkins

US Patent:

7944803, May 17, 2011

Filed:

Oct 1, 2008

Appl. No.:

12/243631

Inventors:

Allen Perkins - Berkeley CA, US

International Classification:

G11B 3/12

US Classification:

369233

Abstract:

A tone arm assembly for use with a rotatable turntable. The tone arm assembly includes a tone arm body supported adjacent to the rotating turntable being horizontally pivotable about a vertically extending axis. A tone arm tube is provided having a longitudinal axis and a first end and a second end, the first end extending within and being supported by the tone arm body and the second end terminating at a shell for releaseably supporting a pick up cartridge. A counterweight is included which is translatable along a horizontal path parallel to the longitudinal axis of the tone arm tube between a first position and a second position, the first position being closest to the shell and a second position being farthest from the shell to adjust contact pressure between a stylus maintained by the pick up cartridge and a record supported by the rotatable turntable. At least a portion of the counterweight is capable of extending fore and aft of the vertically extending axis when the counterweight is positioned on its horizontal path between its first and second positions.

US Patent:

8593929, Nov 26, 2013

Filed:

Aug 8, 2012

Appl. No.:

13/570168

Inventors:

Allen Perkins - Berkeley CA, US

International Classification:

H04R 9/12

US Classification:

369147

Abstract:

A moving coil type pick up capsule having a body, cantilever having first and second ends, a stylus located at its first end and a coil located at its second end and, therebetween, a dampener having an opening therethrough. The cantilever passes through the dampener opening such that the stylus is on a first side of the dampener and the coil is on a second side of the dampener. First and second magnets or yokes are positioned within or proximate the capsule body and spaced from one another to create a gap, the dampener and coil being positioned within the gap such that the fulcrum is located between the stylus and coil and specifically at the dampener. A dampening fluid fills the gap to complete the assembly.