US 1967020 A
Description (OCR text may contain errors)
Patented July 17, 1934 UNITED STATES ANTIFRICTION TOOL Richard w. Canfleld, Middletown, N. Yqassignor to Clemson Bros., Inc., Middletown, N. Y., a corporation of New York No Drawing. Application September 17, 1932,
Serial No. 633,683
This invention relates to an anti-friction tool, and to a method of producing an anti-friction surface upon a tool. More particularly, the invention relates to a hack saw, or other hard steel 6 tool having a working edge and a supporting portion which is coated with a soft metal, so that in rubbing against the work on which it is used,
the soft metal will be rubbed into the hard steel surface of the supporting portion of the blade,
to and will form a smooth, soft bearing layer between the blade and the work.
In the use of hack saws prior to my invention, the problem of friction between the tool and the work has been recognized for a long time, and
315 it has been common to supply the tool, during use, with oil or with an emulsion of oil and water, both to lubricate and to cool the blade. Even at best, however, with oils or other lubricating materials supplied to the blade, the hard, none too so smooth surfaces of the blade are far from ideal bearing surfaces on which to maintain an oil film, but since the requirements of manufacture do not permit of the production of a better bearing surface on the blade, it has long been considered that a relatively high degree of friction is unavoidable.
It has also been common, in the manufacture of hack saw blades and like tools, to coat the tool with a thin layer of a heavy oil or grease in order an to protect it against rust during transit and storage.
It is an object of the present invention to provide a coating for a saw blade, or other tool, which will serve at once to give the tool a more pleasing 35 and saleable appearance, to protect the tool during transit and storage against rust, and which will serve, when the tooi is put into use, to produce a surface on the tool which will afford substantial advantage over the bare surface of the m hard steel. with these and other objects in view, I have now discovered that if the blade or other tool, after it'is manufactured, is coated with a thin layer of a soft metal, this coating may serve, during transit, storage and sale, as both a protective and decorative coating, and when the blade is put into use, the soft metal will be rubbed into the hard steel surface, and a blade with its surface thus treated will operate, particularly with other lubrication, e. g., oil, more easily and efficiently so than a blade which is not so treated.
The coating may be applied in various ways,- for example, bronzing, plating, dipping or in any other manneer causing an effective adherence of a thin layer of the metal to the surface of the tool. I prefer, however, to use bronzing both because of the ease with which the metal may be applied in this way, and because I have found that the fine flaked form of the metal which is used in the bronzing composition is particularly adapted for rubbing into the surface of the blade when the tool is put into use.
The following formula may be given as an example of a composition suitable for use in this manner: I
2 oz. of bronzing powder, consisting of a relatively soft bronze alloy of copper and tin, and 15 gr.levigated graphite to each pint of liquid, the liquid consisting of a clear cellulosic lacquer such as is used, for example, in automobile flnishing, diluted with an equal weight of thinner. I prefer to apply this composition by means of a spray gun, but satisfactory results may be obtained by applying with a soft brush, or by dipping, in which case, however, less thinner should be used.
The above formula is given only as a preferred example of the invention, and may be varied within wide limits. For example, the bronze powder may consist of any good bearing alloy, large numbers of which are well known, and need not be specifically described. In addition to copper-tin alloys, I have found, for example, that the alloys of copper and lead, or copper and zinc, or copper and aluminum, or various combinations of such metals may be used for the purposes of my invention; or instead of the bronze, aluminum powder or flaked lead, or other soft metal or alloy may be used, and as already stated above, the metal may be applied in other ways, as by electroplating, dipping. etc.
I have found it advantageous to include a small amount of graphite in the mixture, since apparently the combination of the graphite and the soft metal produces a lubricating effect greatly superior to that which would be produced by either alone.
Although I have referred in the above particularly to hack saw blades, since the problem is most noticeable in connection with their use, it will be understood that the invention is applicable to 100 various other types of tools, for example, to twist drills, and it is to be understood that all such tools having supporting parts which rub against the work, when coated with a soft metal, are within the scope of the present application.
What I claim is:
1. A hard steel metal-cutting tool having a cutting edge and a supporting portion thesurface of which tends to rub against the sides of the out work when in use, which is characterized by a 110 thin coating of soft metal upon said surface of said supporting portion.
2. A hard steel metal-cutting tool having a 5. A hack saw blade having its sides lubricated with a bronzing composition.
6. A hack saw blade having its sides lubricated with soft metal in fine flake form.
7. A hack saw blade having its sides lubricated with a bronzing lacquer including a flaked bronze and graphite.
8. A hack saw blade having its sides lubricated with a soft metal in flne flake form held on the surface of the blade by a binder adapted to permit said metal to be rubbed into the surface of the blade when in use.
RICHARD W. CANFIELD.
cmrmcma or common 1,967,020 July 17, 1934.
\ 111cm w. 0mm.
It ie hereby certified that error appears in the above numbered patent requiring correction as follows: The drawing shown below should be inserted as art of the Letters Patent; and in the heading to the printed epecification, line 6, strike out the words "No Drawing-J;
July 17, 1934. I R, w. CANFIELD A 1,967,020
ANTIFRICTION TOOL 7 Filed Sept. 17, 1932 W ATI'ORN and that the said. Letters Patent should be read with these corrections therein the. the same may conform to the record of the case in the Patent Office. I,
Signed and. sealed this 6th day of August, A. n. 1935.
Leslie Frazer Seal. Acting Commissioner ,of Patents.