Advanced magnetic circuit to improve both the solenoidal and magnetic functions of string instrument pickups with co-linear coil assemblies

• US 20060156911A1
• Filed: 01/15/2005
• Published: 07/20/2006
• Est. Priority Date: 01/15/2005
• Status: Active Grant

• Current Assignee: Fender Musical Instruments Corporation
• Original Assignee: Fender Musical Instruments Corporation
• Inventors: Stich, Willi L.
• Granted Patent: US 7,227,076 B2
• Time in Patent Office: Days
• US Class Current: 84/726
• CPC Class Codes: G10H 2220/511 Stacked, i.e. one coil on top of the other
• CPC Class Codes: G10H 3/181 Details of pick-up assemblies

Abstract

An electromagnetic pickup for a stringed musical instrument incorporating a magnetic structure placed between two elongated collinear coils of opposing polarity. The magnetic structure includes a number of ferromagnetic polepieces that extend through the collinear coils and two ferromagnetic moderator bars adjacent to and on opposite sides of the polepieces (within the area between the two coils) that are charged with one polarity by high coercive rare earth high coercive permanent magnets attached to the outer surface of the moderator bars.

Claims

1. A magnetic pickup for stringed musical instruments having ferromagnetic strings, the pickup comprising:

a pair of axially spaced coils to have their axis extended perpendicular to the length of the strings;

a plurality of ferromagnetic poles extending through the first and second coils;

first and second coils are separated by first and second ferromagnetic moderator bars adjacent to each side of the ferromagnetic poles; and

high coercive permanent magnets are affixed to the sides of the first and second ferromagnetic bars opposite the plurality of ferromagnetic poles.

2. The pickup according to claim 1 in which two coils are connected, either in series or parallel mode, in an out of phase relationship to each other.

3. The pickup assembly according to claim 1 in which the coils are respectively disposed on a pair of bobbins, the bobbins and ferromagnetic bars being held together by the plurality of ferromagnetic poles that are press fit into the bobbins.

4. The pickup according to claim 1 in which the coils, and the poles are elongated in a direction transverse to the string length as to be responsive to a plurality of parallel strings.

5. The pickup according to claim 1 wherein the separation between the coils is of a greater dimension than the height of each of the coils and the total height of the pickup does not exceed 0.900 inches.

6. The magnetic pickup according to claim 1 wherein the high coercive permanent magnets have approximately half the mass of the ferromagnetic bars.

7. The magnetic pickup according to claim 1 wherein the high coercive permanent magnets are magnetically oriented parallel to the direction of the strings disposed with one magnetic polarity to the ferromagnetic bars which induce the same magnetic polarity into the plurality of ferromagnetic poles and the other magnetic polarity is directed parallel to the strings away from the pickup.

8. The magnetic pickup according to claim 1 in which two the coils are not directly influenced by the dipole function of the high coercive permanent magnets.