US3282665A - Composition for cleaning and lubricating abrasive surfaces - Google Patents

Description

C. M. MYERS Nov. 1, 1966 COMPOSITION FOR CLEANING AND LUBRICATING ABRASIVE SURFACES Filed June 2. 1960 United States Patent 3,282,665 COMPOSITION FOR CLEANING AND LUBRICAT- ING ABRASIVE SURFACES Charles M. Myers, Chicago, 11]., assignor, by direct and mesne assignments, to Thomas G. Poulakidas, Chicago,

Filed June 2, 1960, Ser. No. 33,550 1 Claim. (Cl. 51304) This invention pertains to improvements in a method for grinding and polishing metal by the use of an improved polishing composition.

More particularly stated this invention relates to a method for grinding and polishing metal by the use of an abrasive surface moving at high speed and coated with ma polishing or surfacing composition, including a lubricating ingredient and also including a high percentage of a highly volatile solvent for the lubricating inlgredient. The use of such a composition in the practice of the improved method prevents the polishing composition from becoming dry on the abrasive surface before the lubricating portion of the polishing composition is of the desired consistency to enable the desired polishing action. The periodic application of additional polishing composition to the abrasive surface during the polishing operation enables the solvent present in the added composition to loosen the excessively dried lubricant and the abrasive Particles and the metal particles absorbed by the dried lubricant which has become impacted or loaded into the abrasive surface and causes the thus loaded material to be discharged or unloaded to maintain the abrasive surface clean and well lubricated.

This invention also pertains to an improved polishing composition, particularly well adapted for use in the mentioned improved method, and which improved polishing composition includes, as essential ingredients thereof, a lubricant for the abrasive surface, a penetrating ingredient for maintaining the cutting efliciency of the abrasive surface and a highly volatile and noninflammable solvent tor the lubricant.

This invention also relates to the improvement in the method for compounding or producing the improved polishing composition and the improvements in polishing apparatus well adapted for the efiicient practice of the improved method of polishing and for the efficient use of the improved polishing composition.

In the operation of grinding and polishing apparatus, such as, for example, grinding and polishing latches equipped with cushioned contact wheels and abrasive coated polishing b'elts driven at high speeds, it is common practice to soak a new and invariably stiff polishin'g belt With kerosene or like material to soften the belt to enable the efficient use of the belt on the cushioned contact wheel, and also to coat the abrasive surfac'e of the belt with a grease-like lubricant, as for example, tallow or compounds of similar lubricants. The melting temperature and solidifying characteristics of tallow and the lubricating qualities thereof, adapt it well for such use. The solidified tallow enables the operator to regulate the cutting depth of the abrasive surface of the belt by controlling the amount of tallow added to the surface of the belt. However, tallow also possesses the undesirable characteristic of loading the abrasive surface, particularly when the tallow absorbs large quantities of powdered abrasive and metal particles, thereby to form a substantially solid material impacted into the spaces between the abrasive particles in a substantially hard layer, thereby causing the belt to become very stiff, and also causing the belt to lose its cutting efiiciency. When a belt is thus loaded with such imp-acted material it normally becomes necessary for the operator to either ice stop the polishing apparatus and clean th'e belt or replace the belt or to apply excessive pressure to the work piece being polished. The application of such excessive pressure to the work piece will immediately result in undue Wear of th'e abrasive surface of the belt, possible damage to the work piece due to excessive friction, and undue wear of the backing material of the belt, thereby decreasing the effective life of the belt.

There are, of course, numerous varieties of metal polishing compounds on the market intended for use in the commercial polishing of metal articles by the use of abrasive coated disks, belts, drums and abrasive whee-ls. However, the common complaint respecting such compounds is that they tend to load the abrasive surface, th'e-reby impairing the polishing efficiency of the abrasive surface and decreasing the useful life of the polishing element.

It is therefore one of the prime objectives of this invention to provide an improved method for the grinding and polishing of metal by the use of an improved grinding and polishing composition, whereby the nec'essary lubricant is provided on the abrasive surface in a condition which permits the operator to obtain the desired consistency of the lubricant, whereby to satisfactorily regulate the cutting depth of the abrasive surface, whereby to automatically unload the used lubricant when it has become too dry for satisfactory use while the grinding and polishing. continues, and whereby to maintain the clean and sharp cutting characteristics of the belt which are commonly associated with a new abrasive surface.

Another objective of this invention is to provide an improved noninfiammable and substantially nontoxic grinding and polishing composition including a lubricant and a cutting agent and a high percentage of a highly volatile and noninflammable solvent for the lubricant, well adapted to lubricate an abrasive surface in such a manner as to enable an operator to choose the desired consistency of the lubricant during the polishing operation for the performance of certain aspects of the polishing operation and also well adapted to maintain the abrasive surface at its maximum cutting efiiciency and also well adapted to maintain the abrasive surface clean and free of normal loading of the abrasive surf-ace with lubricating material which has absorbed particles of abrasive and particles of metal.

Another objective of this invention is to provide an improved method for the compounding or blending of ingredients of a polishing composition including a greaselike or fat-like substance, a hydrocarbon mixture, and a noninflammable and highly volatile solvent for the fatlike or grease-like substance.

A still further objective of this invention is to provide an improved grinding and polishing apparatus which is provided with readily controllable composition applying means for applying a grinding and polishing composition including a highly volatile solvent and a grease-like lubricant to the abrasive surface of the polishing element and which apparatus is particularly well adapted for grinding and polishing metal by the use of the hereinbefore identified improvement in a method for grinding and polishing metal and for the use of the hereinbefiore identified improved grinding and polishing composition.

It will be apparent that the present invention possesses the advantage of permitting the operator of the grinding and polishing apparatus to select the desired consistency of the lubricant for any specific aspect of the polishing operation by the addition of the improved polishing composition to the abrasive surface and then permitting the evaporation of the lubricant solvent to continue until the lubricant is of the desired consistency on the abrasive surface. The present invention also possesses the further advantage of providing a noninflammable and substantially nontoxic grinding .and polishing composition which is relatively inexpensive to make and easy to use and which has the qualities of maintaining the abrasive surface clean and sharp and well lubricated, and which composition, when used on grinding and polishing belts, has the further advantage of maintaining the belt in soft and pliable condition. The present invention also provides an improved grinding and polishing composition by the use of which the operator of the grinding and polishing device is enabled to perform .the grinding and polishing operation with a minimum of effort and by the use of a minimum of pressure on the work piece being ground and polished, thereby reducing the required labor and increasing the useful life of theabrasive surface. The present invention also possesses the advantage of providing a relatively simple apparatus Well adapted for the practice of the described improved method of grinding and polishing met-ail.

It will, of course, be recognized that this invention may be embodied in various forms without departing from the spirit thereof. The invention will, however, be described, without desire of limitation, with respect to an improved method of grinding and polishing metal and an improved grinding and polishing composition and an improved abrasive belt-type of grinding and polishing apparatus. Various modifications of the invention may suggest themselves to those skilled in the pertinent arts upon the reading of this specification and consideration of the accompanying drawings and appended claims. Such modifications may, however, come within the scope of the appended claims. Further advantages and the foregoing and other objectives and important novel and useful features of this invention and the specific nature of this invention will be apparent from the following description of the invention, when read in connection with the appended claim and the accompanying drawings in which:

FIGURE 1, is a perspective view showing schematically the improved grinding and polishing lathe apparatus;

FIGURE 2, is a fragmentary vertical sectional view of an abrasive coated grinding and polishing belt, showing, in exaggerated manner, the improved grinding and polishing composition applied in a thin layer over the cutting surface of the abrasive particles; and

FIGURE 3, is a fragmentary vertical sectional view of the abrasive coated belt shown in FIGURE 2, in which the spaces intermediate the abrasive particles are filled with solidified or dried polishing composition which has absorbed quantities of abrasive particles and metal particles and which has become impacted into the abrasive surface.

Referring to the drawings, wherein like elements are identified by like numerals, 1 represents a power unit for the improved grinding and polishing lathe supported on base 2. Power unit 1 is provided with laterally extending arbors 3 for drivingly supporting contact wheels 4 releasably secured to the associated arbor 3 by a nut 5. Contact wheel 4 is preferably provided with a resilient peripheral layer or tire 6 composed, as for example, a suitable type of rubber. Belt 7 is laced over the tire 6 of the driving contact wheel 4 and over the idler pulley or wheel 8, adjustably mounted on base 9. Crank 10 and levers 11 and 12 comprise conventional arrangements for the transverse and longitudinal and pivotal adjustment of idler pulley 8 for the adjustment of the belt 7. An inverted pan-shaped vapor exhaust shroud 13 overlies the major portion of the upper reach or portion of belt 7 and is provided with a suitable exhaust conduit 14. The forward end 15 of shroud 13 extends close to belt 7 immediately adjacent to the contact wheel 4 and overlies the belt 7 transversely thereof to form a dirt shield to protect the operator from material centrifugally discharged from belt 7. A polishing composition dispenser 16 is mounted on shroud 13. Dispenser 16 may be of the spray or of the film dispensing type and may,

for example, also be of the electrically operated or of the pneumatically operated or of the mechanically operated type. Dispenser 16 is provided with a distributing nozzle 17 for distributing a spray or film of polishing composition, withdrawn from dispenser 16, onto the abrasive outer surface of the upper reach of the belt 7. A power unit 18 is provided on the dispenser 16 usable in causing the controlled dispensing of polishing composition from dispenser 16 through nozzle 17 and for driving the composition agitator 19 Within dispenser 16. A suitable control circuit 20 for power unit 18, extends from power unit 18 to a foot actuatable control element 21 mounted on base 2 at a location convenient for use by an operator stationed at the normal position for an operator adjacent the contact wheel 4.

FIGURES 2 and 3 illustrate fragmentary vertical sections of a conventional abrasive coated grinding and polishing belt including a cloth backing member 22, which is normally stiff when new, and which has been provided on its upper surface with a layer of glue 23 into which a layer of abrasive particles 24 have been set in conventional manner. As shown in FIGURE 2, the improved polishing composition, when applied to the layer of abrasive particles 24 forms a uniform layer over the exposed surfaces of particles 24. As shown in FIGURE 3, the surfacing composition, which in common practice may consist solely of tallow or tallow-like or grease-like substances, has become dry and has absorbed many small particles of abrasive and metal, thereby producing a relatively hard compound impacted as at 26 between the abrasive particles 24.

In the grinding and polishing or surfacing of metal items, particularly in those operations where both coarse and fine grinding must be or is preferably done on the same abrasive surface to avoid making time consuming changes in the apparatus, it is common practice to use a hard and dry grease-like or fat-like lubricant, such as tallow or compounds ofsimilar lubricant materials which are normally shape retaining when applied to the abrasive surface. By the use of such lubricant, it is possible to apply a layer of the lubricant to the abrasive surface whereby to cover, to the extent and depth desired, the cutting surfaces of the abrasive particles and by that procedure limit the cutting depth of the abrasive surface. The use of such lubricant, however, has the pronounced disadvantage of loading the abrasive surface, i.e. ultimately filling the abrasive surface to the extent of rendering the abrasive surface ineffective. To temporarily overcome such ineffectiveness, the operator must apply much more pressure to the work piece being polished, with the resulting incurred wear on the abrasive surface of the polishing element, possible damage to the work piece by burning and possible damage to the backing element of the abrasive surface in those instances where Ibelts, discs or drums are used, and possible permanent damage to the abrasive wheel in those instances where such wheels are used and are thus lubricated. The use of such hard lubricants and the normal resulting necessity of applying more and more pressure to the work pieces as the work progresses to accomplish the desired surfacing action impairs the abrading characteristics of the abrasive surface due to the fact that the abrasive surface is not maintained sharp and clean. The hard lubricant soon absorbs large quantities of abrasive particles and metal particles and relatively solid masses of such mixtures become impacted between the abrasive particles of the abrasive surface. When such impacted conditions occur, and they occur regularly, it is normally necessary for the operator, when using such conventional method of polishing, to stop the apparatus and either install a new abrasive surface or thoroughly clean the dirty abrasive surface before continuing with the polishing operation. Such cleaning operations are, of necessity, time consuming and necessarily costly.

The possible use of thin lubricants, such as certain hydrocarbon mixtures, as for example kerosene, or other thin oils, as the sole lubricant for the abrasive surface, is not satisfactory for the reason that in addition to the normal fire hazard presented by the use of such materials, such materials will not solidify during such use thereof to permit the operator to secure the desired layer of hard lubricant on the abrasive surface which is desired to enable the performance of certain aspects of the polishing operations and is also desirable to enable the operator to control the depth of cut of the abrasive surface.

To overcome the above mentioned undesirable characteristics of presently available grinding and polishing compositions, the improved composition comprises an intimate mixture of 22.50 parts by weight of tallow, 32 parts by weight of kerosene, 42.75 parts by Weight of trichloroethylene, and 2.75 parts by weight of oil of Wintergreen. In the improved composition the tallow functions as a hard and dry lubricant, the kerosene functions as a liquid lubricant and cutting agent and penetrating and dispersing agent and as a slow acting solvent for the hard lubricant and as a softener for the backing element when used on cloth or the like backed polishing belts or discs. The trichloroethylene, which is highly volatile, noninfiammable and substantially nontoxic, and which comprises a major portion of the improved composition, functions as a rapid acting solvent for the lubricants, as a blending and dispersing agent for the ingredients of the com-position and as an agent to render the mixture noninflammable. The oil of Wintergreen, in addition to its lubricating function also functions to impart a pleasing aroma to the improved composition.

It is of course well known that various other hard lubricants or compounds of such materials comprise satisfactory lubricants for the conventional methods of grinding and polishing metal. Such other lubricants, however, also possess the hereinbefore mentioned objectionable characteristics common to tallow, as mentioned above. Some of such other lubricants are classified in the group of fatty acid esters which are also fat-like or grease-like, others are fat-like or grease-like p-araflin hydrocarbons, etc., but as a group may be considered as comprising aliphatic materials. Obviously, in such instance where some other suitable fatty compound or grease-like or fatl'ike material is substituted for tallow in the improved polishing composition, then a suitable substitution may also be necessary with respect to the rapid acting solvent for the lubricant. As mentioned above, the important aspect of the improved composition is the inclusion of the lubricant agents having the mentioned desired characteristics as to lubricating qualities and as to hardness and the inclusion in the improved composition of the large proportion of the highly volatile solvent for the hard lubricant, which solvent is readily evaporable at normal room temperatures and which solvent, for safety and health purposes, should be noninflammable and substantially nontoxic.

The improved grinding and polishing composition is preferably compounded by intimately mixing discrete particles of the hard lubricant, such as tallow, with the liquid hydro-carbon mixture lubricant and cutting agent, such as kerosene, to produce a uniform blend of those ingredients, whereupon the solvent for the hard lubricant, such as trichloroethylene, is added to the uniform blend of the hard lubricant and the liquid lubricant and intimately mixed and blended therewith. Thereafter the oil of Wintergreen or other desired aromatic oil is added to the mixture to impart a pleasing aroma to the mixture.

In the use of the improved grind-ing and polishing composition in the grinding and polishing of metal items on a belt-type polishing lathe, such as is illustrated in FIG- URE 1, the belt 7 is first coated with a layer of the improved composition by applying the composition to the abrasive surface of belt 7 by means of the nozzle 17 of the dispenser 16 in which the composition is stored and continuously agitated by agitator 19 to maintain the composition in a condition of uniform and intimate mixture. The high speed of the belt 7, which normally travels at from 5000 feet per minute to 8000 feet per minute, depending upon the particular polishing lathe, the size of the contact wheel 4, etc., quickly discharges any excess composition from the abrasive surface of belt 7, and the abrasive surface of the belt is uniformly coated with a thin layer of the improved composition, as generally indicated in exaggerated manner'in FIGURE 2. The operator then permits the evaporation of some of the highly volatile and rapid act-ing lubricant solvent, which evaporation occurs extremely rapidly, due to the rapid movement of the belt, until the consistency of the composition remaining on the abrasive surface is that desired for the particular aspect of the grinding and polishing operation to be performed. The grinding and polishing operation is then commenced and in a very short period of time the hard lubricant commences to solidify and absorb quantities of abrasive powder and metal powder as the lubricant solvent continues to rapidly evaporate. As soon as the belt becomes dirty or loaded with the mixture of hard lubricant abrasive powder and metal powder and the thus formed mixture becomes impacted into the abrasive surface of the belt, the operator then actuates the dispenser 16 and applies additional quantities of the improved composition to the abrasive surface of belt 7 while the polish ing operation continues. The application to belt 7 of such additional quantities of the improved composition substantially instantaneously loosens or dissolves the impacted and dirty hard lubricant and it is unloaded or discharged from belt 7 by centrifugal force and the polishing operation is continued in the manner described above. Obviously, the above described improved method of grinding and polishing metal items need not be performed by the use of the improved automatic apparatus as described, but instead may also be performed manually by the application of the improved composition to the abrasive surface by the careful use of swabs or similar devices.

From the foregoing description of this invention and from the accompanying drawings, it will be apparent that this invention realizes the introductorily enumerated objectives respecting the improvements in a method and composition for polishing metal, and the improvements.

in the method of compounding the improved polishing composition, and the improvements in apparatus useful in the convenient practice of the improved method of grinding and polishing metal. It will similarly be apparent that the invention also possesses the hereinbefore listed advantages and provides new and useful and novel improvements in a method and composition for polishing metal and method for compounding the improved composition and apparatus useful in the performance of the improved method of polishing metal.

Having thus described and illustrated the above identified invention, the invention is not to be interpreted as being restricted to the specifically illustrated and described embodiments thereof as set forth in the drawings and as hereinbefore described, except insofar as is necessitated by the appended claim and the disclosures of the prior art.

The invention is hereby claimed as follows:

A liquid composition for application to an abrading surface for removing loading or impacted material from such surface and for cleaning such surface, whereby to maintain the abrading characteristics of such surface while simultaneously using the thus treated abrading surface in cutting engagement with a work piece, consisting of an intimate mixture of the essential ingredients thereof which are, 22 parts by weight of tallow, 32 parts by weight of kerosene, and 42 parts by weight of trichloroethylene, said trichloroethylene being substantially nontoxic and also being highly volatile and also being noninfiammable and also rendering the entire composition noninflarnmable, said trichloroethylene also imparting to said composition the ability to substantially instantaneously clean the abrading surface and loosen and remove the loading or impacted material therefrom when the composition is applied to such abrading surface.

References Cited by the Examiner UNITED STATES PATENTS Ellis.

Pilgrim 513 04 Lupo 51-304 Pringle 51281 Lupo 513 06 Larsen 513 05 8 Hamilton 106-8 Be'ltrarn et a1. 51135 Marsh et a1 51304 Edgemond et a1 51-135 High 51-304 Simjian 51281 ALEXANDER H. BRODMERKEL, Primary Examiner.

FRANK E. BAILEY, JOHN R. SPECK, MORRIS 10 LIEBMAN, Examiners.

R. W. DUCKWORTH, D. J. ARNOLD,

Assistant Examiners.

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