US1899463A - Method of and apparatus for grinding and polishing materials - Google Patents

Description

Feb. 28, 1933. I L. E. HOWARD 1,899,463

METHOD OF AND APPARATUS FOR GRINDING AND FOL ISHING MATERIALS Filed March 26, 1950 Patented Feb. 28, 1933 uu rso STQATESPATENT OFFICE;

LESLIE E. HOWARD, 0F LOOKPORT, NEW YORK, ASSIGNOR 1'0 SIMONDS SAW AND STEEL COMPANY, OF FITGHBURG, MASSACHUSETTS, A- CORPORATION OF MASSA- GIHUSETTS METHOD or AND APPARATUS FOR en'minne AND POLISHING MATERIALS Application filed March 26, 1930. Serial lTo. 439,047.

This invention relates to the art of abrad fact that the abrasive material is'not glued or otherwise affixed to the face of the wheel, but loose abrasive is supplied asa powder between the wheel and the surface being treated. When the abrasive is supplied in proper quantities and uniformly distributed across the face of such a wheel the work is more uniform and in general more satisfactory than that obtainable with other types of wheels having abrasive surfaces which deteriorate with use. Heretofo-re it has been very difiicultto effect a good distribution of abrasive even over the face of a wheel operating on the upper surface of a piece of stock, while it has been practically impossible to effect proper control and distribution of abrasive over a wheel operating on an under or abrading both the upper and lower surfaces of a piece of stock; to provide apparatus for 7 these purposes of rugged and durable and yet simple and efficient construction, consist ing of new parts which are also relatively inexpensive to manufacture; and also to pro vide apparatus ofthis character having an improved construction and arrangement of parts.

In the drawing:

Figs. land 2 are respectively diagrammatic side and end views of one embodiment of the invention; and Figs. 3 and 4: are respectively diagrammatic side and end views showing another embodi- -ment of the invention. 7 e

In Figs. 1aand'2, upper and lower polishing wheels '11 and '12, are mounted upon arbors 13 and 14 which are supp'ortedfo-r rotation in bearings (not shown) in the usual manner; Thesewheels are spaced tOTBCBlVl-l a piece of stock 16 for simultaneously polishing theupper and lower surfacesof the stock,

the. latter being'preferably moved against the travel of thewheels. Arcuate guides 17 and 18 which are preferablychannel-shaped in cross section extend circumferentially about the wheels. A portionfof the periphery ofeach wheel is disposed within the sidewalls of these guiding members, preferablybeing spaced slightly from the side walls. The guides 17 and 18 are also arranged so that the base of the channel is spaced from the face of the wheel at distances which dibeneath the hopper isclosed by end and hot tom walls 22, 23. An opening or slot 24 extends through the bottom wall 23 transversely across the face of the wheel 11. This slot and hopper 21 are located well to the right of the center of the wheel 11 so that under some conditions material may pass from the hopper directlythrough the slotahd' be discharged from the apparatus/The lower guide 18 has a similar 'slot 26 which likewise extends transversely across the face 'ofthe wheel 12 and isdisposed in the lowest portion of the guide 18. Abrasive material is supplied from a hopper 27 conveniently located above the polishing wheels, and chutes or pipes 28 and 29 conduct abrasive material re- 9 ranged in the same manner as described with respect to Fig. 1 and channel- shaped guides 31 and 32 are also spaced about the wheels in the same way that the guides 17 and 18 are disposed in Figs. 1 and.2. The guide 32 has a slot 33 extending transversely across the f face of the wheel at the lowest portion of this guide. The upper guide 31 has a bottom Wall 34 extending from the upper end of the guide toward the face of the Wheel. The ends ing the excess abrasive falls harmlessly through the slots and, of course, does no dama e.

The apparatus shown in Figs. 3 and 4 op- 5 36"and 37 ofthe guides are open. Abrasive---erates in the same general manner as that material is supplied to the -apparatus from a hopper 38 through a formation pipe 39 hav- 7 ing a conneotiontl to the side wall of the I i upper guide adjacent the ope'n'e nd 36the1'eof and having a connection 42to the side wall of the lower guide adjacent the open end 37 thereof, Air--jets are formedwithin the formation pipe 39 by air issuing from small pipes or nozzles 43 "and-tfwhich are efiec-. Y tive for translating abrasive material from 1i formation pipe 'throu'gh 'the connections 41 and 42 into thempper and' lowerguides.' l These'jetsare controlled by' val-'ves 46 and: 17 "andare supplied with'air under pressure from 5 20' pipe 4:8. I I "'1' In the operation of theapparatus-shown in Figsll and 2; abrasive material: is permitted 'todescend continuously from thehopper' 27 I throu'gh'th'e pipes '28 and QQ-being conducted-- in 'this' manner to the-convergent qp'a'ssage's formed"between'tlre' guides 17 and: 18, and thewheels with which these "guidesare assol 1 ciatedr 'When these wheels are: operating. in thedirection indicated by the arrows, thew-indage,-that is, the'-friction--of the face of the wheel with the air'envelopingthi'sportion "of thewheehsets up acur-rent which is efiiec disclosedlin Figs. 1 and 2, but in this instance abrasive descending from the hopper 38 through the formation pipe 89 is translated through the--coi1nections 4:1-{ln d-42 by in]ecting air across the pipe '39- and through these connections. This -air is': preferably delivered at a comparatively loW pressure and sufficient"volume through"the air jets 43 and Mtoefiiect the desired distribution transversely of the wheels. The apparatus shown-in thesesviews. is especially-adapted for bufii-ng :where. the. abrasiveis extremely fine,-or'the- Wheel facesare wide, .or both. It is also a valuable applicationrwhere it is desired to-run very Wide. wheels, :as for example, wheelsihavlngfacestlfzeinches and over, with abrasives of polishing sizes as distinguished. from .bufiing abrasive. sizes. These fine abrasives tend. tocakeanddo not flow freely as larger material will. ,Theiair jets43 are eflectivein breaking upa mass of ithis=abrasive and distributing. it uniformly across the face of. a wheel. :By'regulating theamount of airzpassing. from the air jets with respect to the amount ofabrasive falling down the formation pipe 39.,just the right amount of abrasivemay.bedistributed across *tive-t'o -distribute abrasive material-transthe face. ofthe endopeningstof the .upper A versely'a'oross the face of the'wheel: and .also F *to convey this material bircuniferantial-ly about the face-to the-surface of the Stockbe ing-treated. -The guidem'embers l'i and 18 5" keep'the -abrasive material in this current J and a'lsoths'e' membersareeifeotive due to the I icorivergene ofthe passage or-air duct niai- !fi teriall-y-todncrease the velocity: oflthe-air *-stream a's"the stockisapproached* This-ar rangeme'nt'provides a good distribution and l such exact control that the -abradingor pols ishing done by'the top wheel-and the bottom whee-lis alike: -*When the :wheels are;not-operati-ng material: delivered through the pipe r 28 to the hopper 21 is'allowed to :pas srthrough theslot'24'and'to-escape from the guide 17 in this-manners *Thisds a:- desirablefeature as "*itav'oids the possibility dfzhaving this material'collect'betweenthe lower-endof the guide 'l'l' -and' the face oft-he wheel, 'for-it' will be appa-rent thatsuch anoccurrence' might result in sprungarbo'rs 'andgeneral damage when 1r 7 the polis'liingwheels were'started due to their being too grea'tiajsupply of abrasiv'e'on the strip, andpof' courseg tiarried between the wheels.- Abrasive "ism-1S0 permitted-to escape. from' substantially the lowest'portion' of the guide 18 through the slot-26. IC- isfound that H whemthe polishing -wheels are running-at' 5! normal speed the abrasive'is'carried 'by. the sl'ots 2 l 5 and'-'26 and practically none falls 1., ofiwthrough while when thewheelszare standand lower. guides, and thismay beregulated so nicely .thattheamoimt of-abrasive is so small andso uniformly distributed that it appears more like a..fog. or smoke than a stream or massof abrasive. Once within the influenceof-the moving. air set up by the rotation of therwheels, it is rapidly'drawn into the opening between the periphery of the .wheelsand the corresponding part of the easings or guides..-and brought to its point of applicationpreciselyas described with reference to Figs- 1 and 2. .It will be observed thatthe formation. or delivery pipe 89 is disposedfar enouglnto one side of the center of the upper. wheel so that when this wheel is not revolving, such abrasive as may be blown in will drop harmlessly to a pit providedfor this purpose, or a portion of it may drop into the lower casingf82 and fall through the slot 33.. It will also'be'apparentthat the delivery pipe 39 may be replaced by two pipes such as the pipes 28'and 29, as shown in Figs. 1 and 2.

I claim:

1. The combination of-means providing a circumferentially extending channel, a polishing Wheel with a portion of itslperiphery disposed within the channel','-means for supplying abrasive to. the channel andmeans effective while the wheeltisfstationary for discharging abrasive from the channel.

22. The. :combination with. 331% [polishing wheel, of an air duct extending circumferentially about a portion of the wheel, the face of the wheel being disposed within the duct, a conduit connected to the duct for supplying abrasive thereto, and fluid jets for delivering abrasive through the conduit to the duct.

3. The combinatlon with polishing wheels spaced for polishing the opposite sides of a piece of stock disposed therebetween, of air ducts extending circuniferentially about each wheel, the face of each wheel being disposed within the duct associated therewith and spaced therefrom to define a convergent passage about the wheel, the end of each duct belng open at the larger end of said convergent passage, supply conduits connected to the larger end of each of saidconvergent passages, and fluid translating means for delivering abrasive through the conduits to the ducts.

Signed by me at Lockport, New York, thls twenty-second 22d day of March 1930.

LESLIE E. HOWARD.

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