US1518638A - Dry cell - Google Patents

Description

Dec, 9, 1924.?

H. DE OLANETA DRY CELL Original Filed Dec. .22, 1919 ,jv'vuenkoz @0401 A @Q M Patented Dec. 9, 1924.

UNITED STATES PATENT OFFICE.

HAROLD-DE OLANETA, OF NEW HAVEN, CONNECTICUT. ASSIGNOR TO WINCHESTER REPEATING ARMS COMPANY,- OF NEW HAVEN, CONNECTICUT, A CoRPQRATIoN OF CONNECTICUT.

DRY CELL.

Original application filed December 22, 1919, Serial No. 346,694.. Divided and this application filed May 3, 1920. Serial No. 378,457.

The present application is a division of.

my application, Serial No. 346,694, filed December 22nd, 1919, and pertains more especially to the paste'employed in the cell.

In dry cells of the type now found on the market in large numbers, and especially those used for pocket flash lights or hand lamps, the zinc electrode is in the form of a cup in which are contained a carbon electrode with a surrounding body of depolarizing material, and an'exciting paste interposed between the depolarizing material and the side wall of the cup. The depolarizing material usually consists of a mixture of manganese dioxid and carbon which is formed into ablock or cartridge about the carbon electrode and is contained 'within' an envelope or bag of cheese cloth or the like.

In the manufacture of cells ofthis type, the pastewhen placed in the cell ordinarily contains a solution of sal aminoniac, which is the principal exciting agent, and a solution of zinc chlorid, which, owing to its deliquescent nature, serves to keep the paste moist. The depolarizing mixture, con sisting of finely divided manganese dioxid and carbon (graphite), is usually moistened with a solution containing ammonium chlorid and zinc chlorid, so as to facilitate set up, for example, as a result of the presence of impurities in the zinc,- o'r.by reason of differences in the molecular structure of the same at different parts of the cup. Under present conditions. ofnianufacture and distribution, there is usually a considerable interval between the time when the cell is first assembled and the time when it reaches the consumer foruse. It is not uncommon for the cells to remain in the factory aweek or longer, owing to delays in packing and shi 'iping. Furthermore, when they leave the factory it takes some time for them to reach the retailer. and, of course, they may remain on the shelf of the retailer for a long period before they are purchased and used. Consequently When a cell is finally put into use, the zinc cup is likely to be considerably eaten away, and the active life of the cell is, therefore, seriously impaired. 7

One of the primary objects of my invention is to eliminate the above mentioned drawback as far as possible. I provide a cell in which the action of the sal ammoniac onthe zinc while the cell is being shipped and while it is on the shelf is avoided to a large extent. The cell. of my invention does not have maximum cflicicncy when first assembled. but it reaches maximum efiiciency some time thereafter, in other words. at about the time that it comes into the hands of the user. ln this manner the life of the cell in the hands of the user is considerably increased.

Another object of my invention is to simplify and improve the process of manufacturing dry cells of thc type indicated. In ordinary methods of manufacture, there are numerous drawbacks and inconveniences arising out of the incorporationef the sal ammoniac and zinc chlorid inthe same' body, more particularly in the paste. For

example, there are difliculti'cs-as regards th'e' proper proportioninge1 the two solutions which are commonly employed. Again, the

sal amnioniac-containing-paste diiiicult .to

handle in the factory'owing to the fact that sal ammoniac is a clinihingsalt, Oneof,

the greatest. object-ions, howeverfis tliafl when sal ammoniac is incorporated in the paste before the latter is placed in the cell, the paste will not keep for any length of time. It has to be used imn'icdiately after being mixed up, as otherwise there is apt I to be aformation of mold.

"',. ',Anothe'r object, therefore, of my present constituting the positive electrode.

"invention is to overcome these difficulties and-disadvantages incident to the manufacture of the cells,-

To these and other ends, the invention posed between the side wall of the cup and the depolarizing material is a paste 4:. The depolarizing cartridge is usually contained bag or envelope 5 of cheese cloth or thelike. It is centered in the cup at the. bottom by av suitable centering washer 6. At

the top of the cell. the latter is sealed in any suitable manner asby a 'pitch seal 7 on top of a paper washer 8. The carbon electrodeis provided with the usual contact ca 9. I a i n carrying out my invention, I rovide a paste which is initially devoid 0 sad ammoniac. The paste is preferably composed of wheat flour or some other cereal, zinc chlorid solution,an d a mercury compound.

In makin tup a batch of paste for the manuf'acture o v a number of cells, I mix together,

for example, 12.5, kilograms of wheat flour, 50 litres of zinc chlorid solution at 27 Baum, and 12.5 grams of mercuric chlorid. The ingredients are mixed together .until all of the flour dissolved, and the mass is stirred, whilebeing cooked, until a stiff paste is formed. The cooking is effected be-" fore the paste is placed in the cell.

i The depolarizing body preferably com-.

prises a mixture of manganese dioxid, graphite, and sal mmon'ac, for example, in

the proportions of 37.5 units of manganese hydrate, 12.5 units-of graphite and 10 units of'sal ammoniac. These ingredients, which are in a fine state of subdivision, are mixed with water until the mass is lastic and homogeneous, whereupon it is owed into the block or cartridge 3 about the carbon electrode 2 in a manner well understood in the art.

The paste will keep for a long time and.

does not have to be used at once owing to the fact that the zinc chlorid is of an antiseptic nature and acts as a preservative for the vegetable substance, e. g. wheat flour.

The drawbacks incident to the incorporation in the paste of ammonium chlorid,

which tends to create a bacterial food, are

eliminated.

\Vheu the cell is first put together, the am monium chlorid does not immediately C0112 mence its attack on the zinc, owing to the fact that it must first traverse the paste. The sal ammoniac passes o'ut'only gradually from the cartridge into the paste and to the zinc. Thus the cell,is not .at maximum efficiency when first assembled, as is ordinarily the case. but reaches maximumefliciency after a definite interval has passed, depending upon the distance between the depolarizing cartridge and the sidewall of the zinc cup. For example, with the smaller sizes of cells commonly used for pocket fiash lights, the distance which has to be traversed by the sal: ammoniac before it reaches the zinc, is such that maximum'efliciency is not obtained for a period varying from two weeks to a month. In a larger size, where the sal ammoniac has to traverse a greater distance, the conditions usually obtaining in a freshly made cell do not obtain-for approximately three months. Therefore there is-likelihood that the cell will not reach its maximum efiiciency until about the time that it is placed in use. At any rate the life of the cell in the hands ofthe consumer is considerabl increased owing to the fact that the lengt ammoniac acts on the zinc previous to'the use of the cell, is considerably reduced.

In the case under discussiomthe sal ammoniac passes outwardthroug h the porous envelope 5 of, the cartridge into the paste of time that the sal i and to thezinc, and the zinc chlorid in the paste passes into the cartridge; but it will be apparent that the invention is not limited to a cell wherein the depolarizing cartridge has a porous envelope. Regardless of whether or not an envelope is employed, the paste takes up sal ammoniac from the cartridge and the cartridge takes up zinc chlorid frdm the paste." Furthermore, these 'SllbSlHjlC8$ are distributed as needed for the best working ofthe cell.' Heretofore, in

manufacturing cells wherein the paste con-- tained both zinc chlorid and ammonium chlorid, there. was considerable difficulty in properly proportioning these two substances. It was necessary to weigh the substances and to compare the density of their solutions, em, and even wheregreat care was exercised in compounding the paste, the results were not always satisfactory. In the present case, "however, the process of manufacture-is considerably simplified, because it is not necessary to mix the chlorids and because such great care in attempting to reach a definiteproportion of the ingredients unnecessary. With my improved cell, the ammonium chlorid is fed or supplied to and taken up by the paste in the proper quantity forthe best working, and

the zinc chlorid is fed to and taken up by the cartridge 'in the proper quantity for best working, regardless of the quantities of those substances'which are used, within certainzlimits.

The chlorid of mercury in the paste serves the usual purpose of amalgamati'ng the zinc. So far asmanufacturing advantages are concerned, it will be understood that a paste made in the manner herein described, which is devoid of ammonium chlorid when first compounded, will keep better and is much easier to-handle than a paste in which ammonium chlorid is incorporated. The ammonium chlorid not only starts the formin of mould, but climbs out'of the paste an over the containing vessels and utensils employed in the storage and handling of the paste, thus causing much inconvenience. Owing to these drawbacks, and the tendency of the sal ammoniac to dry up the paste, it

so not reach its maximum efficiency until some has been impossible heretofore to use paste prepared any considerable length of time in advance of the time when it was placed in the zinc cups, and there was, therefore, considerable waste.

While my improved cell .ordinarily does time'after it has leftthe factory, it can be readily brought to maximum efficiency b placing it in a closed circuit. When the ce 1 1s used for lighting a small lamp, for example, the passage of electric current through the cell has the effect of hastening th passage of the electrolyte, viz, the sal ammoniac, to the zinc. Of course, the zinc chlorid in the paste serves as an electrolyte to a sufficient extent to establish a current through the, cell when the circuitis closed, and such current has the effect of drawing out the sal ammoniac from the depolarizing bodyso that the former will quickly reach and act-on the zinc for the establishment of a strong current. While, therefore, cells made in accordance with the present invention meet the resent conditions of slow distribution to the consumer, this advantage is not coupled with any appreciable lack of efficiency in the cell as freshly assembled.

The mercuric chlorid used in the paste as an amalgamator is of an antiseptic or preservative character, as well as the zinc'chlorid, and hence all of the materials added to the wheat flour or the like tend to preserve the same and arrest decomposition.

While have referred herein to sal ammoniac as being'the principal exciting agent and to zinc chlorid as a paste moistening agent having a certain electrolyte value, it is to be understood, of course, that I do not limit myself in all aspects of the invention to the use of these particular sa.lts, or, in fachto the employment-of two distinct salts.

Various changes may be made in the details of the procedure and in the composition and arrangement of parts as herein described, without departing from the scope of my invention as set forth in the claims.

What I claim is:

1. In a dry cell,a paste containing cereal, an amalgamator and an electrolyte, the electrolyte content when the paste is fresh consisting substantially entirely of a salt material of a preservative character, said paste being designed to receive and distribute-an I excitant placed in juxtaposition thereto.

2. In a dry cell, a stiff paste containing cereal, an amalgamator and an electrolyte, said electrolyte consisting substantially entirely of a salt material which preserves the cereal against mold, and said paste being designed toreceive and distribute an excitant placed in juxtaposition thereto.

3, In a dry cell having a zinc cup and a depolarizing cartridge, a stiff, precooked paste interposed between said parts and containing cereal and an electrolyte, substantially the whole electrolyte content being mold preventing but said paste being adapted to absorb and distribute another electrolyte placed in juxtaposition thereto in the cell.

4. A paste for use in dry cells, containing v wheat flour, zinc chlorid solution and mercuric chlorid in approximately the proportions of 12.5 kilograms of flour, 50 litres of zinc chlorid solution at 27 Baum, and 12.5

grams of mercuric chlorid.

5. A paste for use in dry cells, comprising a stiff cooked mass consisting of wheat flour, zinc chlorid solution and mercuric chlorid.

6. In a dry cell, a paste cooked before the same is placed inthe cell and comprising a stiff mass of cereal, chlorid solution and mercury compound mixed together before cooking, said paste being adapted to receive and distribute an excitant placed in juxtaposition thereto.

7. A stiff, precooked paste for dry cells, I

thereto.

9. A stiff paste for dry cells, containing juxtaposition cereal and an electrolytic content practically H devoid of ammonium chlorid, said paste being of a character such that it will receive 10. A stiff paste for dry cells, cooked before the same is placed in the cell, and comprising .a cereal and a weakelectrolyte solu tion mixed together before cooking, but subdevoid of any material forming or tendin to form with the'cereal bacterial food, an said ast being adapted to receive and slow y distribute an excitant placed in juxtaposition thereto.

In witness whereof, I have hereunto set my hand on the 30th day of April, 1920. r

HAROLD DE OLANETA.

stantially

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