US2030122A - Electrolytic condenser - Google Patents

Description

w. F. sTRAuBfEr AL' ELEGTROLYTIG CONDENSER Flled Feb 1l, 1952 Feb. 11, 1936.

Patented Feb. 11, 1936 l*UNITED STATES PATENT oFFlcE ELECTROLYTIC CONDENSEB Delaware Application February 11, 1932, SerialNo. 592,252

Y In Germany February 13, 1931 3 Claims.

The invention relates to an electrolytic condenser in which the various plate-shaped electrodes or the various successive turns of a single electrode are arranged at some distance from vone another and are separated by an intermediate layer. In fact, the condenser plates of electrolytic condensers are frequently rolled up in order to save space. The intermediate layer whereby the windings o-f the electrodes are spaced apart from one another consistsin many cases of an absorbing substance containingithe electrolyte, for example, of asbestos or.paper.

It has been found that in this case undesirable phenomena may occur due to the fact that gases are developed in theI electrolyte and that the intermediate layer, which is in contact with the electrodes, prevents the gas bubbles from ascend-` ing. At the point at which gas bubbles remain behind between the electrode and the intermediate layer the electrode will be corroded which I results `in a considerable decrease of the length of life of the condenser.

According to the invention this drawback is removed by having the various electrodes or the '25 successive turns of one electrode separated from one another by spacing members whereby paths are left free for the ascent of gas bubbles.

VSaid spacing members may be formed, for example, by rods of insulating material such as consists of two parallel wound plates` separated from one another by spacing member which does not pass the electric current or only to a slight extent, such as celluloid, it is important to per- `-forate said spacing member. 'Ihe transmissibility for the electric current may be still further improved by drawing one or more wires of insulating material through the perforations of the spacing member, said wires running alternately on either side of the spacing member in such manner however that they do not come into contact with the electrodes.

The invention will be explained more fully with reference tothe accompanying drawing, in which,

Fig. 1 represents schematically a lateral elevation oi' a condenser according tothe invention;

Figures 2 and 3 represent sections of dierent i'orms of execution taken on the line AlI--III of 65 Figure l; and,

Fig. 4 represents a detail oi' another form of execution.

The construction according to the invention is of great importance with condensers whose electrodes consist entirely or partly of one of the 5 metals of the rst sub-group of the fourth principal group oi the periodic system of the elements and which are coated with a layer of an oxide of these metals.

Referring to Figure 2, a condenser vessel I, 10 which simultaneously acts as one of the electrodes, consists, for example, of irongwhereas a rolled up electrode 2 `consists of zirconium coated with a layer of zirconium oxide. I Said vessel is filled with a solution of potassium hydroxide. 15 The successive turns of the electrode 2 are spaced apart by one or more undulated strips 3 of celluloid or other suitable substance.

The fact that the bottom of the vessel I also consists of iron warrants a suillcient Velectrical 20'.

Fig. 3 represents two electrodes 2 and 6 rolledup in parallel and consisting,.for example, of titanium coated with a layer of titanium oxide.

In this case the spacing members are formed b y 30 glass rods 'l extending in the longitudinal direc# tion of the condenser. 'Ihe vessel 8 consists in this case, for example, of ebonite or of an artificial resin with a filling material, such, for example, as that known under the registered trade- 35 mark philite. The rods 1, too, may be made oi this material if desired. It is evident that in the embodiments shown in Figures 1 and 2 gas bubbles have an ample opportunity of ascending in the electrolyte. 40

If in the construction of Figure 3 instead of the rods 1 use would be made of a rolled-up undu` lated plate oi' celluloid or other insulating material which does not take up liquids and which consequently does not become conductive, the 45 resistance of the condenser would be considerably increased.

Said drawback may be overcome in this case by taking care that apertures are left free in the celluloid, for example, by perforating the latter. 50

Fig. 4 represents a portion of two condenser plates 2 and 6 between which such a perforated strip I of celluloid is arranged. The portion oi' this strip on the left-hand side 'of the line IV, IV

is shown in section. Through the holes is laced acopperwirewhichbringsthespacestothe left and the right of the celluloid strip into connection with one another.

It is evident that several variations are possible without departing from the principle ot the invention.

The condensers described with reference to Figs. 3 and 4 are alternating current condensers.

Those shown in Figs. 1 and 2 are destined for smoothing pulsatory direct currents. It in the condensers according to Figs. 3 and 4 a metal plate without oxide illm, for example, a nickel plate is substituted for one ot the titanium plates, one obtains a condenser having a slight internal resistance and suitable for smoothing a pulsatory direct current.

We claim:

l. In an electrolytic condenser, a compact roll composed of at least two electrode sheets and an undulated strip oi' insulation material said strip being interposed between the vtwo sheets so as to separate same, a container for said roll and an electrolyte solution within the container adapted to fill the spaces therein. said compact roll being immersed in said solution, and means for determining the internal resistance of the constrip into conductive rela- 2. In an electrolytic condenser, a compact roll composed of at least two electrode sheets and an undulated strip of insulation material interposed between the two rolled sheets so as to maintain each sheet separate from the other along its entire surface, a container for said roll and an electrolyte solution within the container into which said is immersed, means for adjusting the internal resistance of the unit comprising means having a substantially high electrical conductivity arranged so as to form a low resistance path between the electrolyte on one side of the insulation material and the electrolyte on the other side thereof to Vthereby reduce the resistance'of portions of the path and at the same time reduce the length of the electrical path between various points of the two electrodes.

WILLEM STRAUB. HENDRICUS JOHANNES LEMMENS.

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