US2298261A - Pen - Google Patents

Description

Patented Oct. 6, 1942 rnN g William Frederick Mittendorf, New York, N. Y., and Max JosepLStumbock', South Orange,

N. J., ass'ignors to Baker & Company, Inc., New- I ark, N. J., {corporation of New Jersey No Drawing;

Application November 29, 1940, Serial No. 367,770

'8 Claims. (01. 120-109) This invention relates to pens and is concerned in particular with pen nibs.

Pens, such as pens for fountain pens, consist of a pen nib of gold'alloy, for instance 14 carat gold alloy, to the pointed end of which there is secured a pen tip of hard metal which serves as the writing point of the pen. The pen normally tip usually contains at least one metal of the. platinum group of metals, such as osmium, ru-.

thenium, or iridium, 'withor without the addition ofother metals such as tungsten, cobalt, molybdenum or the like. The pen tip may -be preformed to have a regular shape and be of regular size, for instance in the form of a small sphere,

and is secured to the pointed end of the pen nib by means of electric resistance welding or the like.

Our invention consists in constructing pen nibs of gold alloys containing up to 15% manganese,

which alloys may further contain up to 15% palladium. The gold alloys preferably have a gold content of from 29% to 85%, whereby the alloys comprise gold alloys of from 7- to carat value, and will contain at least 0.5% manganese but preferably not in excess of 10% manganese and, if palladium is added, at least 1% palladium. The alloys may otherwise contain the usual connot necessary in order to raise the resistivity it does add to such increase as shown by the fact that the replacement of equal amounts of copper and silver in the above alloy by 5% palladium raises the resistivity from'81 to 94, so that a ma stituents of gold alloys, such asup to copper, up to 40% silver, and nickel, cadmium, etc. Specifically, our invention provides pen nibs of 10to' 14 carat gold alloys containing 1% to 5% manganese with or without 1% to 5% palladuim, which alloys mayadvantageously contain appreciable amounts of copper and silver preferably in substantially equal amounts.

In the welding of tips to pen nibs the nib and tip are brought in contact whereupon an electric current flows throughthe nib and the tip" resulting in melting of the metal of the nib. The

molten nib metal flows around part of the tip to form, on @illing, a firm and secure grip, whereby the tip and nib are welded together. It. has been found that the weld is not always completely satisfactory when the nib comprises a gold alloy and the tip comprises metal which at elevated temperatures is highly volatile, such as osmium, iridium or ruthenium. The nib metal, of course, has a melting point considerably below that of the tip metal and when the electric current flows through the tip and nib the greatest amount of heat is developed in the tip from where it is transferred to the nib causing the latter to melt as hereinbefore described.

The addition of manganese or of manganese and palladium tends to raise the electric resistance of the gold'alloys whereby such gold alloys having a higher electric resistance are especiallysuitable forthe construction of pen m'bs. With pen nibs according to our invention it is, there:v

fore, possible to obtain a considerably better electric weld with pen tips even when the latter contain appreciable quantities of highly-volatile com-J 1 ponents, in that the electric current produces; more heat than heretofore in the pen nib itself wherefore the pen nib tends to melt without the necessity of heat transfer from the tip or at least with considerably less heat transfer from the tip,

with the result that it is no longer necessary to produce as much heat in the pen tip as had been a necessary heretofore. A.- gold alloy containing about 58% gold, 20% copper and 20% silver for instance has a resistivity of 81 ohms. The replacement in this alloy of equal parts of silver and copper by about 3% manganese and 4.5% palladium raises the reels;

tivity to 158. Although the palladium itself is of gold alloy containing up to 15% palladium has certainadvantages even without the additional presence of manganese.

In welding a pen nib accordingtoourinvention to a pen tip the pen tipdoes not heat up as much as it would with an ordinary g'old alloy pen nib and thus the highly volatile metal is subjected less to volatilization. Volatilization is undesirable in that it causes oxidation in the welding area thusresulting in a poor bond between the nib and the tip, and in that it affects the carefully selected and balanced metallurgical structure of the tip. The elimination of such disadvantages results; therefore, in a better bond in that the bond between nib and tip is more secure and the structure of the tip is less affected. 1

The metallurgical structure of the gold alloys containing manganese is such that pen nibs manufactured therefrom are strong and springy.

Furthermore, there is no danger of deleteriously I changing the crystalline structure of the nib during the heating accompanying the securing of the tip to the nib, irrespective of whether such securing is carried out by resistance welding or any other type of welding or by soldering, wherebysuch alloys are capable of withstanding without damage the higher temperature to which they are subjected during the welding process as the result of the higher electric resistance thereincluding of and oi withstanding more easily any accidental overheating.

We have further found that pens oi the gold alloys hereinabove specified are harder, can' be age-hardened more readily and have much better tarnish resistance than comparable gold alloys without the presence of manganese or manganese and palladium, thus providing tarnish and corrosion. resistant pen nibs of great strength combined with springiness. I

Our invention, therefore, makes available a gold pen nib of a novelcomposition not heretofore known which has great tarnish and corrosion resistance, possesses permits electric resistance welding of hard metal points such points which contain as" an integral component a metal or metals which. are highly volatile at elevated temperatures in such manner that overheating of such pen points is eliminated whereby it becomes possible to obtain in all cases a secure. and excellent bond between nib and'tip by spontaneous fusion of nib metal on passing of an electriccurrent through contacting nib and tip without Iusionoi' the tip and without overheating or either nib ortip.

After thetip has been secured tothe nib the tip and the pointedend of the nib are slit and the-pen is finished in accordance with usual practice.

What we claim is: I g 1. A pen nib of gold alloy containing'up to fifteen (15) per. cent oi a metal taken from the group comprising manganese and palladium.

2. A pen nib or gold alloy containing up to ten (10) per cent manganese. I

3. A pen nib oi goidalloy containing up to fitteen (15) per cent manganese and up to fifteen (15) percent palladium.

great hardness and the welding thereto for instance by715 alloy containing from three (3) per cent to five 'taining from one (1) percent to five 1 cent manganese and five (5)] per cent palladium.

4. A' pen-nib of a 7 to 20 carat gold alloy containing from one-mums) per cent to ten (10) per cent manganese and from one (1) per cent to fifteen (15) per cent palladium.

5. A pen niboi a 10 to 14 carat gold alloy con- (5) per from three (3) per cent to 1.6. A pen' nib of an approximately 15 carat gold (5) per cent manganese.

7. A pen nib of an approximately 15 carat gold alloy containing from three (3) per cent to five (5) per cent manganese and from three (3) per cent to five (5) per cent'palladium.

8. A writing pen consisting of a pen nib of a "I to-20 carat gold-alloy containing from one-half (0.5) per centto ten (10) per cent manganese and from one (1) to fifteen (15) per cent palladium, and a pen tip'oi hard metal composition.

said nib and. tip being slit, whereby a writing pen is obtained.