Electromagnetic pickup for a stringed musical instrument having ferromagnetic strings and method

• US 4,878,412 A
• Filed: 01/09/1989
• Issued: 11/07/1989
• Est. Priority Date: 06/22/1987
• Status: Expired due to Fees

• Current Assignee: Martin H. Resnick
• Original Assignee: Martin H. Resnick
• Inventors: Resnick, Martin H.
• Primary Examiner(s): Witkowski, Stanley J.
• Application Number:
  US07/295,003
• Time in Patent Office: 302 Days
• Field of Search: 84/1.14-1.16, 336/83, 336/110
• US Class Current: 84/726
• CPC Class Codes: G10H 2220/515 Staggered, i.e. two coils side by side
• CPC Class Codes: G10H 3/181 Details of pick-up assemblies

Abstract

A pickup for an electrical instrument of the stringed type which comprises a pair of coil assemblies disposed within hollow magnetic bushings, the coils having its winding axis perpendicular to the strings, a hollow cylindrical shaped permanent magnet made of rubber-like plastic positioned around the outside circumference of each coil assembly, parallel to the winding axis of the coil. The direction of coil winding and magnet polarity around the first bobbin is opposite to that of the second bobbin. The magnets being disposed within the body of the pickup, said magnets serving as a sleeve for mounting coil assemblies and coil forms and suppresses microphonics by acting as a dampening means. A very dense and improved magnetic flux path passes from the inside surface of the hollow magnets through the coil assemblies disposed within said magnetic assemblies, said flux then sweeping the string area in a radial motion therein producing a novel tone having improved sustain qualties. The basic geometric shapes of the pickup components lend themselves well in regards to simplifying manufacturing procedure.

Claims

1. An electromagnetic pickup, adapted for use with a stringed musical instrument in which the strings are formed of ferromagnetic material, comprising

a nonconductive, non-magnetic body having at least one hollow cavity,

at least one conducting coil wound on an electrically nonconductive, non-magnetic core form,

a flexible permanently magnetic bushing adjacent to and surrounding said coil,

said coil and magnetic bushing being arranged within said body so that in use they will be disposed perpendicular to the surface of a plurality of the strings of said instrument, whereby said magnetic bushing provides permanent magnet means to direct a magnetic field into said coil and at least one of said strings.

2. The pickup of claim 1 in which said body has two spaced apart hollow cavities in each of which is disposed one said coil wound on one said core form surrounded by one said bushing, and each of said coils are electrically connected in operational relationship to each other, whereby each said magnetic bushing provides permanent magnet means to direct a magnetic field into the coil it surrounds and at least one of said strings.

3. The pickup of claim 1 in which said body has one said cavity in which one said bushing is looped into a figure eight shape so as to form two circular spaces and one said coil wound on one said core form is disposed within each of said spaces, the said coils being electrically connected in operational relationship, whereby said bushing provides permanent magnet means to direct a magnetic field into each of said coils conjunctively with at least one of said strings.

4. The pickup of claim 1 in which said body contains one said cavity, in which one said bushing is disposed around its periphery, surrounding two said coils which are wound on one said core form in a manner such that they are physically spaced apart from one another by a layer of nonconductive material which surrounds said core, said coils being electrically connected in operational relationship, whereby said bushing provides permanent magnet means for directing a magnetic field into said coils and at least one of said strings.

5. The pickup of claim 1 in which an even number of said coils is present, arranged in pairs so each pair is electrically connected in series out of phase with one another and operationally connected in a humbucking relationship.