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Publication numberUS2173218 A
Publication typeGrant
Publication dateSep 19, 1939
Filing dateOct 18, 1937
Priority dateNov 26, 1936
Publication numberUS 2173218 A, US 2173218A, US-A-2173218, US2173218 A, US2173218A
InventorsEmanuele Zoppi
Original AssigneeEmanuele Zoppi
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method for whetting files, rasps, and the like
US 2173218 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Patented Sept. 19, 1939 PATENT OFFICE METHOD FOR wm-z'r'rmo mas, misrs, AND run mm Emanuele Zoppi,

Genova. Italy No Drawing. Application October 18, 1937, Se-

rlal No..169,753. In Germany November 26,

This invention relates to a method for whetting filgsl, rasps and the like by etching by means of It has already been previously proposed to dip files to be whetted into an acid bath without preliminary treatment. This method has the disadvantage that the files were considerably reduced in weight, whilst the whettlng obtained only lasted for a very short time. This method is therefore not of practical value. According to the present invention the grease is first removed from files by treating them in an alkaline bath, they are then treated in a bath of hydrochloric acid, then in a bath of nitric acid and subsequently in a bath of hydrochloric acid, whereupon any acid which may be adhering thereto is neutralised.

' The advantage of the new method resides in the fact that the baths which are used can be produced at low costs, that the files do not lose in weight as a result of the treatment, and the method can be carried out byfan unskilled workman. By means of the new method it is possible to obtain in an economical manner sharp g5 and resistant teeth. The method may be carried out for example as follows.

For the removal of grease there is used a soda lye containing 50 g. caustic soda (NaOI-I) to one litre of water. In this lye the files are boiled for 80 about half an hour. The files are then removed from the lye and rinsed in water and brushed.

The files are then placed into a second bath consisting of 50 parts by weight commercial hydrochloric acid and 50 parts by weight of water. The files are allowed to remain in this bath for 12 hours without the application of heat.

In this bath all adhering substances are removed and the surface is prepared for the succeeding third bath in which the files after having been again rinsed and brushed are placed.

This third bath may be regarded as the renewing bath, it consists of 20 parts by weight of nitric acid of 42 B. and 80 parts by weight of water. The files are allowed to remain in this 4!! bath for from 5-10 minutes without the applica tion of heat.

During the first moments there are formed fine bubbles which adhere to the points of the teeth, enclose these and protect them against the action of the acid. After 2-3 minutes the bubbles disappear and the bath can attack the whole file. It is important during the treatment in the third bath to repeatedly withdraw the files therefrom and to again immerse them therein.

us After treatment in the third bath the files are 4 Claims. 01. -24) again washed and brushed. They are then placed for a period of 5-10 minutes into a fourth bath which has the same composition as the second bath. After rinsing and brushing the files are treated in a fifth bath which consists of water 5 and unslaked lime.

For this purpose there are used 5 litre of water and about 100 g. unslaked lime (09.0). It is sufiicient if the files are allowed to remain in this bath for about 10-20 minutes. They may howit) ever be allowed to remain, therein for a longer time (hours or days).

After treatment the files are again washed and brushed. They are then dried for example in saw-dust or by means of an air current and finally l5 greased, preferably with mineral oil.

The washing of the files between the treatments in the separate baths is preferably effected in hot water. Further it is preferable when taking the files from one bath to immediately placethem 20 into the washing water and from the washing water immediately into the next bath so that on the passage from one bath to the other they are not exposed to the air for too long a period of time.

The files are preferably placed into the baths in a vertical position.

I claim:

1. The method of sharpening files, rasps and the like, which comprises the following steps in 30 the order mentioned. viz: first, subjecting the articles to the de-greasing action of a boiling alkaline bath consisting of 50 g. of NaOI-I to one litre of water; second, removing the articles from the alkaline bath and rinsing them in water; third, placing the rinsed articles in a bath consisting of approximately equal parts by weight of hydrochloric acid and water, for about twelve hours, at normal temperature: fourth, removing the articles from the hydrochloric acid bath and 40 again rinsing them in water; fifth, placing the rinsed articles in a bath consisting of twenty parts by weight of nitric acid of 42 B. and eighty parts by weight of water, for from five to ten minutes, at normal temperature; sixth, remov- 45 ing the articles from the nitric acid bath and after rinsing the same, neutralizing any adhering acid in a milk of limebath.

' 2. The method of sharpening files, rasps and the like, which comprises the following steps in 60 the order mentioned, viz: first, subjecting'the articles to the de-greasing action of a boilingv alkaline bath consistingof 50 g. of NaOI-I to one litre of water; second, removing the articles from the alkaline bath and rinsing them in water; so

third, placing the rinsed articles in a bath consisting of approximately equal parts by weight of hydrochloric acid and water, for about twelve hours, at normal temperature; fourth, removing the articles from the hydrochloric acid bath and again rinsing them in water; fifth, placing the rinsed articles in a bath consisting of twenty parts by weight of nitric acid of 42 B. and eighty parts by weight of water, for from five-to ten minutes, at normal temperature; sixth, removing the articles from the nitric acid bath and after rinsing the same, placing the articles again in a. hydrochloric acid bath like that of the third the like, which comprises the following steps in the order mentioned, viz: first, subjecting the articles to the de-greasing action of a boiling alkaline bath consisting of g. of NaOH to one litre of water; second, removing the articles from the alkaline bath and rinsing them in water; third, placing the rinsed articles in a bath consisting of approximately equal parts by weight of hydrochloric acid and water, for about twelve hours, at normal temperature; fourth removing the articles from the hydrochloric acid bath and again rinsing them in water; firth, placing the rinsed articles in a bath consisting of twenty parts by weight of nitric acid of 42 B. and eighty parts by weight of water, for from five to 4. The method of sharpening flies, rasps and the like, which comprises the following steps in the order mentioned, viz: first, subjecting the articles to the de-greasing action of a boiling alkaline bath consisting of 50 g. of NaOH to one litre of water; second, removing the articles from the alkaline bath and rinsing them in water; third, placing the rinsed articles in a bath consisting of approximately equal parts by weight of hydrochloric acid and water, for about twelve hours, at normal temperature; fourth, removing the articles from the hydrochloric acid bath and'ag'ain rinsing them in water; fifth placing the rinsed articles in a bath consisting of twenty parts by weight of nitric acid of 42 B. and eighty parts by weight of water, for from five to ten minutes, at normal temperature; sixth, removing the articles from the nitric acid-bath and after rinsing the same, placing the articles again in a hydrochloric acid bath like that of the third step above; seventh, removing the articles from the last acid bath and after rinsing the articles, neutralizing any acid adhering there-

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6968619May 13, 2003Nov 29, 2005Ultradent Products, Inc.Method for manufacturing endodontic instruments
US7322105Nov 18, 2005Jan 29, 2008Ultradent Products, Inc.Methods for manufacturing endodontic instruments by milling
US7398598Nov 17, 2004Jul 15, 2008Ultradent Products, Inc.Methods for manufacturing endodontic instruments
US7665212Feb 23, 2005Feb 23, 2010Ultradent Products, Inc.Methods for manufacturing endodontic instruments
US7743505Feb 23, 2005Jun 29, 2010Ultradent Products, Inc.Methods for manufacturing endodontic instruments from powdered metals
Classifications
U.S. Classification76/24.5
International ClassificationC23F1/06
Cooperative ClassificationC23F1/06
European ClassificationC23F1/06