US351256A - Moses g - Google Patents

Description

(No Model.)

M. G. FARMER.

ELEGTRO MAGNET.

No. 351,256. Patented Oct. 19, 1886.

Z O m 0 w 1 Mn E a 4 E EU \A m q Hm m, B 1 j @511 M ahiq mm N. PETERS. Phme-Lilhn m hur, Wnshin tun, B. C.

To all whom it may concern:

* UNITED STATES PATENT OFFICE.

MOSES G. FARMER, OF NElV YORK, N. Y.

ELECTRO- MAGN ET.

SPECIFICATION forming part of Letters Patent'No. 351,256, dated Gotober 19.1886.

Application filed June 11, 1886. Serial No. 204,886. (No model.)

Be it known that 1, Moses G. FARMER, a citizen of the United States, and a resident of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Electro-lliagnets, of which the following is a specification, reference being had to the accompanying drawings.

This invention is animprovement in that class of electro magnets which are distinguished by a helix and movable core, and which are commonly known as axial magnets. 7

The chief object of this invention is to produce a very sensitive magnet of this general character, and at the same time one of great power, by means of which a comparatively. t'ecble current may be caused. to exert a strong attractive force. J

The device by means of which. my invention is carried out may be generally described in the following manner: There are two helices, placed in line in close proximity to each other. Each helix is compound, consisting, really,of twoindependent coils, which I shall designate as the main and local coils or helices, since they are connected in independentcircuits, as will be more fully hereinafter explained. \Vithin the local helices are sectional iron cores, tubular, and fixed at short distances apart. The movable portion of the core consists of a number of iron cylinders carried by a brass rod, the cylinders being arranged one in each. stationary coresection and formed with a flange that extends into the space between two adj acentseotions. The local coils orhelices are included in a local circuit in which there is sufticient current to impart polarity to the cores. While the main coils are in the main or working circuit the local circuit is constantly closed, and the other is made and broken, as may be desired. The direction of winding of the local coils or helices is such as to. cause the stationary core-sections of each helix to repel the movable cores within them and to attract those in the adjacent sections. The main coils are so wound that a current flowing through them adds its strength to the current in one local coil and neutralizes that in the other, according to the direction of the current in the main circuit, from which it follows that the armatures may be moved in either direction and their movement utilized for various purposes by directing through the main coils a current in the proper direction.

The details of the construction of this device are illustrated in the accompanying drawings, in which Figure 1 is a vertical central section of my improved electro-magnet, showing the circuitconnections; and Fig. 2 is a top plan view of the same.

The helices are supported between heads or plates A A, forming part of a frame, in conjunction with theb'ars B B, and are in line with each other and a short distance apart. Each helix is composed of two coils, as G D O D. The inner helices, G C, are in a branched local circuit, E, containing a battery, F, and a rheostat, G or G, in each branch, by means of which the resistances of the two branches may be varied. The outer helices, D D, are in the main or operating circuit H.

The inner helices, O O, surround stationary tubular cores composed of the soft-iron sections K K, which are formed with ashoulder at each end and held apart by the interposed brass or non-magnetic rings a. The heads A A serve to hold the core firmly together.. Within the tubular sectional cores are the series of armatures L L, carried by a brass rod or tube, M. The armatures L L are short tubes of soft iron formed with flanges b, or in any other manner, so as to contain a greater mass of iron at that end which is nearest to the end of the next adjacent tubular stationary coresection. The armatures are of a diame ter to fit looscl y within. the sections K K, and are separated from each other by interposed rings of non-magnetic metal a. They are secured to the rod or tube M, and the sections K K placed over them in building up the core, so that the heads or flanges Z) will be contained in the spaces between the sections K and permit the rod or tube M to have a longitudinal movement of limited extent through the helices.

I face the armatures LL with brass or a non-magnetic substance, in order to prevent adhesion from residual magnetism. in case of cont-act with the stationary core-sections, and

they are made quite light in comparison with the cores K K. lhe objectis to impart t0 the rod or tube N a limited movement in either direction by closing the circuit through the coils D D. This movement may be utilized for a great many purposes. For example, the instrument may be used in conjunction with proper contacts as a polarized relay, or it may be used for opening and closing a valve or ringing a gong, or for any other like purpose, and it is particularly adapted for operating any such instrument where the expenditure of considerable force is necessary, and where the current to produce it is comparatively weak. Inorder to accomplish this the inner coils are wound or the current directed through them in such manner as to impart to the ends of the stationary core-sections in one helix polarities opposite to those in the corresponding ends of the sections in the other helix. The same current magnetizes the inner or movable sections, and by reason of their relative positions it imparts to both stationary and movable sections the same polarity at their corresponding or adjacent ends. One end of each movable section being larger than the other, and being also nearer to one of the adjacent stationary sections than its smaller end to the other, such larger ends are attracted by the adjacent stationary sections and repelled by those surrounding them. These forces which, by reason of the closed local circuit,are constantly exerted upon the movable armatures are opposite and normally should be equal. To secure this the proper balance is made by adjusting the rheostats G.

The coils D D are so wound that a current flowing through the main circuit H will circulate around the two cores in the same directiou. A current impulse of given direction, therefore, in the circuit H will assist the local current in one of the helices, G, and neutralize its effect in the other, so that the movement imparted to the armatures and their supporting rod or tube will be toward that helix in which the current is neutralized.

The two coils of the helix may be wound in armatures secured to a rod or tube and mov able within the core-sections, as set forth.

8. The coinbinationot' two co-operating helices, each composed of a main and local coil, stationary sectional cores contained in said helices, and a series ofarmatures secured to a rod or tube,one armature in each coresection, so as to form a compound polarized magnet when energized by a current in the local coils, as set forth.

4. The combination of two co-opcrating helices, each consisting of a main and local coil, stationary sectional cores contained in the helices, the sections being separated by short spaces and magnetically insulated, and a series of cylindrical armatures secured to a rod or tube, and formed with a greatermass of iron at one end, and movable withi u the core-sections, as set forth.

5. The combination of two cooperating helices, each consisting of a main and local coil, stationary sectional cores contained in the helices, the sections being separated by short spaces and magnetically insulated,and a series of cylindrical armatures secured to a rod or tube, and formed with flanges extending into the spaces between the core-sections, as and for the purpose set forth.

MOSES G. FARMER.

Witnesses:

Tnro'rnY DAME, M. F. KEEFE.

Images