US398122A - Best available cop - Google Patents

Description

(No Model.)

BEST-AvAxL/ALE COP 'Patented-rbflg, 1889.

sEsrAvAiLAeLECoP UNITED STATES PATENT GEEICE.-

EDlVARD T. BIRDSALL, l? NElV YGRII, N. Y.

sTATic-IN-DUCTION e ENE RAToR.

SPECIFICATION formngpart of Letters Patent No. 398,122, dated February 19, 1889 Application filed November 14, 18S-8. Serial No. 290,786. (No modelJ To all whom t may concern:

Be it known that I, EDWARD T. BIRDSALL, of the city and State of ANew York, have invented an Improvement in Electric Induction and Inuence Machines, of Which the follow-A ing is a specification. Y

Electric induction and influence machines have heretofore been made in which two disks of glass have been revolved in 'opposite directions, and upon the surfaces of-the glass there have been strips of foil, and the static charge induced has been received upon combs, and there have been conductors connectedwith the combs through which the current has.

been transmitted to any instrument or apparatus-such, for instance, -as Geissler tubes f A or other appliances for demonstrating electric effects.

My present invention relates to the details of construction of such machine, whereby -I am enabled to simplify the same, lessen the cost, and render the apparatus more efficient.

It is to be understood that this apparatus is especially adapted for the use of students, schools, and colleges, and it is' available for demonstrating electrical operations in which static electricity is made use of.

In the drawings,Figure l is an elevation of the apparatus. Fig. 2 is a vertical section through the axis of the disks. Fig. 3 is a horizontal plan, partially in section, of the combs; and Fig. l is an elevation of the central portion of one of the disks, showing the mode of fastening the saine to the hub.

The base A is usually quadrangular, having cross-pieces 2 at the ends and standards B at the sides supporting the shaft C, and also an axis, D. At one end ofthe shaft C is a crank-handle, E, and upon the shaft C between Jthe standards B there are two beltwheels, F and G, with belts 3, topulleys 4 5 upon the respective hubs H and I. These hubs H and I are preferably of wood and tubular, and through them the axis D passes, such axis being` formed of a strong wire. The

'glass disks K and L are each formed with the central opening, 6, notched at its edges for the reception of the screw 7, and the respective hubs II I are fitted into the central openings of the respective disks, and the screws 7 pass into the hubs through the notches in the glass for securing the disks to the inner der t0 prevent moisture condensing upon "such disks and interfering with the development of the electric current, and there are strips of foil secured to the outer faces of the respective disks, which strips usually-occupy radial positions, as represented in Fig. l. One of the belts 3 is. .crossed and the other is straight, so that by rotating the shaft C by the handle E the hubs H and I and the respective glass disks connected with them are revolved rapidly and in opposite directions.

.The brushes N are made of line wire or preferably of bunches of tinsel, and these are vsupported by the diagonal arms O, which arms are of sheet metal, and each end of each arm is made with a lateral projection, 8, that is folded around to inclose the base of the bunch of wires or bunches of tinsel, and these are securedby solder run into a loop formed by the folded lateral projection 8. These arms O are received into saw-cuts in the standards B and are held by the axis D,passing through a hole in each arm, and the bases of the sawcuts in the standards are at about an angle of forty-five degrees to the horizon, so that the respective arms and brushes stand diagonally and in opposite directions with the brushes against the faces ofthe respective disks. I find this is a cheap, coiwenient, and efficient mode of constructing the brushes,

, and it allows for replacing the brush es cheaply and rapidly, should they become injured.

Upon the end base pieces, 2, are the columns P, which are made of wood and hollow for the reception of the glass rods Q, and at the upper ends of these glass rods Q are the knobs R, forming the bases of the combs S, and each knob R has a cylindrical connection, l0, around the upper end of the glass rod. I find in practice that these knobs, combs, and cylinders can be cast in one, of pewter or similar soft metal, around the upper ends of the glass rods, and they remain firmly connected thereupon, especially whore the glass rod is slightly indented with a file or otherwise at.

one side to prevent the knob turning thereon, and through each knob a hole is cored or l formed by a pin introducedinto the mold and IOO afterward driven out of the casting, through which hole the wire T passes, and each wire T is L-shaped or bent at a right angle and terminates with the knob or electrode U. The 5 wires T are to fit the holes inv the knobs RY tightly, so that there will be sufficient friction to allow forswinging the wires and knobs nearer together or farther apart, as indicated by the dotted lines in Fig. 1, so as 'to lengthen or shorten the are between the electrodes.

In practice thiselectric'machine is very efiicient, and it occupies but asmall space, and for transportation the parts can be separated with facility and packed into a small space, and there is but little difculty in taking the machine apart or putting it together, because the Wires T can be pulled out from the knobsV R and readily inserted, and by Vwithdrawing" remox'f'ed from position and packed, so aste prevent injury to such glass disks in transe .the arms o can ais be nffed' ma fain the standards and packedA separately.

r siam my invenaon nshed surfaces and provided with strips ofV ing, in' combination with the Wood'e' hubs H I, tting into the central openings the respective disks and securedb'fy'scrvvs, aiidthe removable axis D, standards `B, and' Abase substantially asset forth. v 4. 3 5 2.,The knobsR, combs S, and cylinders 10,'

the axis-D the hubs and glass disks can be portatiomand ivhn the axis D is r'iv'ed 1. The glass disks K and L, having foil and each having a central notched pel'i'v eEsT AVAMBLE cciD Y B, and the arms O and brushes N, the stand- .ards being slotted or saw-cut diagonally for the reception of the'ams, and the arms being perforated for thepassage of the axis, substantially as set'feitli` .s 4i The veombinatim in ,the electric in'a chine, f-tlie glass disksls L, Wooden hubsH I, to v'vl'i'hl the glasfsfdisks; are connected, the base A and standards" B,;th removable' @fris D, passing ,through the and taidads', the shaft G, belt-vili "ls-Fv G', and belts to pnlT ley iii res' ilvfhbs, the arins'fO slots itli', standards', t e" o' ft'l,V @dds f the arifi's, the @the glass, rods Q, faire wiesr, passing g` nios", and t ele i-odes at the ends of h wires, rally asset forth.

Signed by ine this 8th day of November, 65

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