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Publication numberUS1344388 A
Publication typeGrant
Publication dateJun 22, 1920
Filing dateAug 16, 1919
Priority dateAug 16, 1919
Publication numberUS 1344388 A, US 1344388A, US-A-1344388, US1344388 A, US1344388A
InventorsEisenmann Carl W
Original AssigneeEisenmann Carl W
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Combination magnetic and electric polarity-indicator
US 1344388 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)


APPLICATION FILED AUGJS. l9|9l Y Patented June 22, 1920.



Specification of Letters Patent. Patented June 22, 1920,

Application filed August 16, 1919. Serial No.y 318,00.

y To all lwhom it may concern:

Be it known that I, CARL W. EISENMANN, a citizen of Germany, residing at Nebraska City, in the county of Ctoe and State of Nebraska, have invented certain new and useful Improvements in Combination Magnetic and Electric Polarity-Indicators; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

This invention relates to new and useful improvements in combination magnetic and electric polarity indicators, and consists essentially in the provision .of a modified compass, with a plurality of indicating needles, one of which is non-magnetic and so directed relative to the magnetic needle as to indicate directly the direction of the flow of an electric current.

My invention consists of a simple and efficient device of this nature, having various details of construction, combination andarrangement of parts which will be hereinafter fully described, shown in the accompanying drawings and then specifically defined in the appended claim.l

My invention isk illustrated in the accompanying drawings which, with the letters of reference marked thereon, form a part of this application, and in which:

Figure l is a plan View of my polarity indicator.

Fig. 2 is a cross sectional View through thek same, and y v Fig. 3 is a detail view. Reference now being had to the details of the drawings by numerals:

l designates a cylindrical casing havin a glass face 1 at each end, said cylindrica caslng having two spacmg rings 6 therein,

, Said dial is centrally apertured to receive the stafl'1 or pin 3', and upon said staffare mounted two needles, designated respectively by numerals 3 and 9, at right angles to each other and spaced apart upon'either side of said dial. The ends of said pin have bearings in sockets formed in the inner sides of the glass faces.

Cn the side of the dial facing the mag'- netic needle are printed the words Magnetic direction, and upon the other side of the dial and facing' the non-magnetic needle appear the words Current direction.7` These needles have definite and fixed relative directions, so that when viewed from the end of the staffl adjacent the nonmagnetic needle, the magnetic needle will point north and the other west. y

By this arrangement, the needles will have definite fixed directions according to the law of relation between the direction of a current in -the wire and the magnetic field surrounding the wire. For instance, when the instrument is placed over a wire carrying direct current, the non-magnetic needle will `point directly in the direction of the fiow of out directly the direction of an electric cury rent, a novel means is provided.

What I claim to be new is:

The combination of a magnetic and electric polarity indicator, comprising acasing,

a balanced rotatable element consisting of a magnetic and a non-magnetic needle rigidly n secured to a spindle mounted rotatably iny bearings, an individualy dial for each needle,

said needles being positioned at right angles -to each other in aparticular fixed direction,

so that they respectivelyy indicate the direction of a magnetic field and ofan electric current. n

c In testimony whereof I hereunto affix my signature.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2644919 *Nov 25, 1950Jul 7, 1953Western Electric CoMagnetic axis and polarity testing device
US2772392 *Sep 21, 1953Nov 27, 1956Deutsche Edelstahlwerke AgMagnet pole indicators
US3753089 *Dec 6, 1971Aug 14, 1973IbmElectronic switching transient detector and method for locating electrical power supply noise sources
US6230415 *Jul 7, 1999May 15, 2001Pedro FodorElectric compass
U.S. Classification324/133, 324/228, 324/259
International ClassificationG01R19/14
Cooperative ClassificationG01R19/14
European ClassificationG01R19/14