US2455567A

US2455567A - Microphone pickup and volume control

Info

Publication number: US2455567A
Application number: US709864A
Authority: US
Inventors: Armond Harry De
Original assignee: Rowe Industries Inc
Current assignee: Rowe Industries Inc
Priority date: 1946-11-14
Filing date: 1946-11-14
Publication date: 1948-12-07
Anticipated expiration: 1965-12-07

Description

Dec. 7, 1948. 4,135 ARMQND 2,455,567

y MICROPHONE PICKUP AND VOLUME CONTROL Filed Nov. 14, 1946 IN VEN TOR.

, A WW 0/5 APMO/VD ATTOlP/VZY Patented Dec. 7, 1948 MICROPHONE PICKUP AND VOLUME CONTROL Harry De Armond, Toledo, Ohio, assignor to Rowe Industries, Toledo, Ohio Application November 14, 1946, Serial No. 709,864

2 Claims. I

- The present invention relates to an electric pick up device for use with stringed instruments in which the tones produced may be passed to a suitable amplifier and not only enlarged, but also the individual action of the string may be changed as desired, and it is an object of the present invention to provide a simplified arrangement of parts in which the pick up mechanism may be.

suitably located on the face of a stringed instrument and readilyv positioned with the proper magnets under the proper strings for correct use of the device; to further simplify arrangement of the several parts and particularly the mounting oi the same on the instrument in addition to locating the same with respect to the pick guard normally used in such instruments.

A further object of the invention is to provide a unique construction of rheostat or volume control of a compact type which may be also mounted on the instrument and which is so arranged as to permit the same to be very economically manufactured and yet provide a large range of variation in volume control for the instrument with which it is to be used.

Further objects and advantages are Within the scope of this invention such as relate to arrangement, operation, and function of the related elements of the structure, to various details of construction and to combinations of parts, elements p r se, and to economics of manufacture and numerous other features as will be apparent from a consideration of the specification and drawing of a form of the invention, which may be preferred, in which:

Figure I is a top plan view of my invention applied to a mandolin;

Figure II is a diagrammatic view of the pick up showing formation and location with respect to the pick guard of the instrument;

Figure III is a top plan view with the cover of the pick up removed;

Figure IV is a transverse, sectional view taken on the line IVIV of Figure III;

Figure V is a transverse, longitudinal sectional view taken on the line VV of Figure III.

Referring to Figure I in the embodiment of my invention illustrated in connection therewith, I provide a pick up electromagnetic unit l adapted to be located under the strings of the mandolin as shown in Figure I. The pick up unit has a top cover 12 and a bottom support or base I4. The cover plate 12 is made of brass and the base l4 may be made of steel sheet metal. The base unit l4 carries the magnet unit and also is provided with means whereby the complete pick 2 up I0 is supported on the instrument. To this end, the bottom 16 of the base unit I4 is provided with a plurality of spaced struck up spring fingers l1 and I8 formed from the metal of the bottom l6. Between these spring clips I! and I8 is located a tongue I9 also struck up from the bottom l6 and since the same may be made of sheet steel these elements may be made resilient. In order to connect the pick up ID to the instrument, I provide a supporting rod 20 which is arranged .to be passed through the eyes formed by the curved fingers l1 and i8 underneath which is the spring tongue is arranged to press the same against the fingers l1 and I8 and hold the rod. 20 by friction in any particular position of ad justment with respect to the pick up l0. Suitable openings 2! and 22 in the sides of the base unit M are provided through which the rod 20 passes so that the rod 20 supports the pick up in this manner.

The other end of the rod 20 is provided witha bifurcated supporting bracket 24, the two ends of which are adapted to slide under the knurled nut of the bridge clamping the bracket 24 in place, and since the rod 20 is fixed to the bracket, it will be seen that the pick up I0 is supported therefrom with the magnet unit arranged to be looked under the required strings of the mando lin.

The electromagnetic unit itself consists of a plurality of cylindrical magnets =30 insertedinto a plastic core 32 which has a base 33 and a top flange 34 forming, in effect, a spool around which a large number of turns of extremely fine wire 35 may be wound as required, the same constituting the magnet unit 36.

I provide a magnet 30 for each pair of strings of the instrument (or each single string in a guitar or the like) and accurately align each magnet with respect to its corresponding string or strings. Moreover, I vary the magnetic effect of certain of said magnets for some of the strings compared with others, This, I accomplish by varying the space between the upper end of the magnet and the strings (as by cutting oif some of the magnets or lowering them in the core) or by using magnets of varying magnetic strength. For instance, I may obtain stick magnets from No. 1 to No. 5, graded according to the magnetic power thereof. In this way, these are made all the same length and arranged under each string as desired to bring out the correct amplification for that particular string.

The wires 35 are connected to the microphone cable and to this end, I provide a unique method of supporting the cable Ml. To this end, I provide the bottom l6 of the base Hi with a tongue 42 adjacent one end thereof which is bent over the cable 40 as shown in Figure III. Moreover, I provide the bottom It with a supporting shelf 43 which has an end upwardly turned portion 44 with an opening therein through which the cable 40 passes to be secured to the wire 35, the tongue 42 being pressed around the cable M], as shown so that the same is securely and satisfactorily held in place, and there is no danger of the cable being disconnected the magnet wires.

It will be also noted that I provide an attaching and locating pad 41 forming an end extension on the base M, the tab or foot M being adapted to extend under the pick guard and aid in properly locking the pick up it on the instrument.

One suitable means for locking the magnet unit 36 in the base l4 consists in providing an anchoring pin or indentation 48 in the'bottom f6 as shown in Figure V, which extends upwardly there-from a short distance and through which the plastic core 32 of the magnet unit 36 may be pressed to properly anchor the unit in the base l4;

Referring to the cover [2, illustrated in Figure II, it will be seen that the same has a top plate 5!? provided with a longitudinal opening 51 a transverse bridge 52 and an end opening 53. The cover 50 has a depending peripheral flange 50 and a small tunnel formation 55 to fit over the cable 40. The cover [2 is retained on the upstanding sides of the base 54 by being made to form a press fit thereover and the depending flange 54 has suitable openings 55 through which the rod 20 passes to further secure the cover :2 to the base M.

It will be noted that the bridge 52 forms a reinforcement for the cover and when the cover unit is made of brass this bridge 52 is intended to pass under said strings of the mandolin which it is desired notto amplify in view of the normal string thereof.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than is herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

What I claim is:

1. An electronic pick up device for stringed instruments adapted to be located between the strings of said instrument and the front face thereof, said device including a relatively thin electromagnetic pick up unit including a core comprising a plurality of vertically arranged individual magnets and a body of plastic insulation having a flat top and bottom into which said magnets are inserted; a winding surrounding said core; a casing therefor comprising an elongated base having a bottom plate; means in said bottom plate to locate said plastic mold in the casing, said base having a cover therefor, said cover having an elongated opening beneath some of the strings of the instrument between the same and said magnets and a connecting bridge across said opening, said bridge adapted to be located between certain other of said strings and the corresponding magnet.

2. An electronic pick updevice for stringed instruments adapted to be located between the strings of said instrument and the front face thereof, said device including a relatively thin electromagnetic pick up unit including a core comprising a plurality of vertically arranged individual magnets and a body of plastic insulation having a flat top and bottom into which said magnets are inserted; a winding surrounding said core; a microphone cable. for connection to an amplifier; a casing having an elongated base having a bottom plate; means in said bottom plate to locate said plastic mold therein; said base having. a transverse extension L adjacent one end; an upstanding outer flange HARRY DE ARMOND.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,37 6,841 Tirrill May 3, 1-921 2,207,341 Dickerson July 9', 1940 2,294,861 Fuller Sept. 1", 1942