US2598637A - Grindstone wheel dresser - Google Patents

Description

y 27, 1952 A. J. ENGLE 2,598,637

GRINDSTONE WHEEL DRESSER Filed May 1, 1947 INVENTOR.

Patented May 27, 1952 UNIT'E D STATES PATENT OFFICE GRINDSTO NFFEZZZZEL DRESSER Andrew J. Eng'le, Chicago, 111., assignor-bf onehalf to' James E. Kennedy, Chicago, Ill.

Application May 1, 1947,=Serial'-No.-'745,266 2 Claims. (01. 125-11) I This invention relates to an improved type of a grindstone or emerywheel surface dressing device. It is particularly adapted to provide uniformly applied pressure to the cutting face of the grinding wheel surface.

In dressing the faceof-a worn down grindstone, an operator holds to the edge thereof a dresser tool which consists of a-s'eries of freely revolving toothed wheels moving about a common shaft. The shaft is mounted in a yoke or a U-type holder. The latter is generally mounted in a wooden handle to provide a" suitable and convenient means to hold the tool while it is in use. The'soderstrom' Patent Number 1,395,606 is illustrativeof one type. Another'type is shown in the Patent Number 602,106 to Charles Roberts. Though there are many others'these will serve as'typical examples and will illustrate the present types'used by the tool industry to refurbish grinding wheels.

In resurfacing grindstones'and similar devices, the operator generally presses a hand type grindstone reconditioner suchas shown by 'So'derstrom for example, against the outer periphery of the grindstone. The first impulse'of' most operators is to press quite heavily the reconditioning tool or dresser against the grindstone surface. By doing so, the grindstone is dressed-more quickly. Unfortunately the pressure notuniformly ap plied for no matter how hard the operator triesto do so it varies as thesurface is dressed. There'- fore the application of uniform pressureto the grindstone is haphazard. Thus in time the grindstone tends to be out: of round and develops high and low spots. Such spotsand variations in the roundness of the grindstone are decidedly disadvantageous for a craftsman using such deficient grindstone cannot properly sharpenhis tools, cutting edges or even dress down to dimensional requirements a job without encountering considerable loss of time, patience and economies of operation. 1

In addition many grindstones of natural stock or even of the so called better quality having synthetic binders therein frequently have faults and "soft spots" and shoulders within their structure. In the course of usage such faults and soft spots are worn out more rapidly and the depletion of the grindstone is considerably greater. The gouging or unevenness in the surface of the grindstone caused by excessive wear at such faults and soft spots isfurther-accentuated since a dresserwhen applied to the face or periphery of such a grindstone tends to follow the contours of the worn out hollows and therefore the depletion of the grindstone by gouging is increased 2' I considerably. In the -hands=of an extremely skillful grindstone dressing mechanic, a good deal of the unevenness can beremoved with a'manuallyoperated dressing-tool. I Nevertheless, thegrindstone never recovers fully itsoverall efficiency,

and cannot be usefully employed -on'- projects orjobsrequiringextremely carefuland close tolerance grinding.

It therefore is-an'objectof my invention toprovide an improved-grindstone dressing device that will apply-pressure to'theface of the grindstone at a uniformrate.

A further object of my invention isto provide an'improved grindstone dressing device than canbe easily, conveniently and'readily-attach'ed to the framing of thegrindstone while d ressingtl'ie peripheral surface thereof.

A still further object of my invention is to provide an improved grindstone wheel dressing device Wherein the pressure on the surfacing'gear can be uniformly transmitted without gouging or pitting of theperipheral grinding surface of the grindstone.

A still further and'a'dditio'nal object of my invention is to provide a mechanical grindstone surface dressing device wherein additional pressure whenever required can be uniformly applied in selectedincreme'nts to the" face of the'g'rindstone.

These and other objects, adaptations, vari ations and modifications" can be varied considerably by one'ski'lled in'the art and still be within the ambit of the fundamental concepts underlying my invention which is described clearly and, definitively hereinbelow and of which the preferred embodiment is illustrated in the attached d'rawing'forniin'g' a p'art'hereof.

In the drawing for sake of convenience and ease of reference, like figures refer to similar numeral notations used in the specification. Therefore'Figure 1 shows a perspective of my improved grindstonewheel dressingdevice rest ing in position on the frame (shown principally in the phantom sketch) of the grindstone wheel. For sake of clarity a clamping'means, such as theordinary C type clamp whichcanb'e'used to fasten the dresser to the frame is not shown.

Figure 2 is a'pla'n view, partly in section, of 7 sentially of a channeled substantially U-shape frame l whose ends I2 and I4 are open. Slidably mounted within the channel of the frame l0 and near the open ends l2 and I4 thereof are bearings l6 and I8.' The bearings support the shaft 20 on which are mounted a plurality of the well known toothed dressing wheels 22 that are in contact with the grindstone periphery 24 shown in a phantom sketch.

To maintain the bearings 16 and I8 in parallel alignment a yoke-like member 26 'is provided ad frame 10. The ends 28 and 30 of the'said yoke are slidably engaged within the outstandng webs Illa and b of the channel of the -U- shaped frame 1., A fastening means "such as screws 32 fasten the ends 28 and 30 to the re spective bearings. A reenforcing bar 34 transversely placed across the open end of the yoke 26 adds rigidity'and strength and prevents wobble of the toothed gear like dressers'22 when pressure is applied during the dressing process. 4 At the upper part or apex of the yoke 26 is a hole 36.; On each side of the hole 36 in the yoke are placed washers 38. Through the yoke hole 36 and washers 38 is inserted a spindle 40. The principal part of the uppermost portion thereof isa thread 42 which is engaged by a nut 44. The nut 44 is fixed immovably to the frame of the channel In. The top'of the spindle 40 termiopen.

In this manner grindstones badly pitted can be dressed smoothly for there is at all times a uniform pressure applied across the face of the stone.

In hand operation, the operator cannotmaintain a uniform pressure across the face of the stone for the pit in the stone may come up unexpectedl or even at times there may be a hole in the stone which the dressing device may un- I handoperated'grindstone dressing device strike thru and cause'marring as well as damage;

' As the stone is dressed down, more pressure is 1 imparted by turningthe knob 46 and which is within the open areaof the U-shaped channelcover. Whenrthis occurs, then the teeth of a transmitted fromlthe screw 42 thru. collar 4! on the washer 39'and in turn onthe yoke 26. I The latter transmits the pressure to the bearings l6 and i8 slidably mounted within the channel frame- 10. As the bearings l6 and I8 move forward inparallel juxtaposition; they carry the shaft likewise' and thus in turn transmit the pressure to the cutting teeth 22. 1 The pressure is applied uniformly to the face 5 of the grindstone for the bearings move simul-..

taneously in rigid parallel relationship; If for some reason,the teeth shall encounter a pitor I a depression on the face of the stone, then the nates in a handwheel 46 which propels or re- V l Small bar 54 or if desired a bar slightly .longer springi48 prevents the teeth from falling into or following such depression. As the surface is' dressed down, the'teeth will eventually turnout a uniformly circular stonelwhose face will be dressed parallel to .the' edges of the teeth 22.

Having described. hereinabove the essential concepts underlying my inventionfI wish to include all those variations and modifications including the preferred embodiment as illustrated in the attachedv drawing that will fall within the I scope of the spirit of my invention as definedin than the width of the channel frame [0 can be p welded to the bottom and, near the'ends l2 and 14 of the frame In. These bars54 act'as stops when the dresser is used, or at'times, they prowide a convenient place to hold the dresser to the frame of the grindstone by means of some fastening device such as an ordinary c-type clamp (not-shown). r I

In actual use the bars 54 mounted on the lowermost part of the channel'frame 10 are butted against or evenplaced'on the edge of the frame 56 of thegrindstone. 24. It maybe.

held against the frame by the operator orheld jinpositionby any holding means such asthe conventional =C-type clamp. In placing the dressingdevice in position for action it is necessary that the dressing teeth edges be placed in the hereunto-appended claims. I Iclaim:

1. A 'grindstone dressing; device comprising a U-shaped channel? the saidu -shaped'channel formed into a U-shapedframe, "an openin between the extending armsjof said u-sh'apecl frame, the said U-shaped frame arms having open ends thereon, bearing members slidably mounted within'the u -shaped channels forming T the said open end arms," a means to hold said the desired position so that they contact uni- I L formly the face 24 of the stone to be dressed.

When the device is fastened properly in place ;and with the grindstone revolving, the operator igradually turns the hand wheel 46 until the gear teeth .22 just barely touch the 'grindstone face 24.

hand wheel 46 and the movement of the yoke 26, 'since it acts on the washer 38 and in turn Qon the yoke 26, both of which are slidably mounted on the .spindle 46. The operator then I turns again slightly the hand wheel 46 and the V ;teeth 22 are'gradually but uniformly pushed jacross gface. If the face 24 Jof the stone should be ipitted orgouged then the spring-48 by acting on the yoke 26v thru'the washer 38 keeps the teeth from striking into the pit and thus breaking it The spring 48 cushions the action of the the entire face 24 .of the grindstone surbearing members in parallel juxtaposition within the said open'end arms, the said meansto hold said bearing members in parallel relation comprising a V-shaped yoke, the ends of said '-"-yoke attached to said slidablebearing members,

the apexof said oke having therein an opening, a spindle inserted therethrough, screw threads on that part of the said spindle above the said opening in thelapex of said yoke, a

Z threaded nut mounted within the base of saidf U-shaped frame to engage thesaid threads on the spindle, a hand wheel mounted fixedly on that end of the said spindle. protruding through said U-shaped frame base, and a sprin mount- 'ed on that part of said spindle protruding through said apex of theyoke to'keep the apex of said yoke in contacting.juxtaposition with the said threaded portionof said spindle. 5

2. In the apparatusof claim 1, a helical spring j mounted 'on the; lower portion of said spindle protruding within the saiclyoke, to maintain.

the said apexin:contacting. juxtaposition with the threacled portion of thesaid spindle.

-ANDREW'J. ENGLE'."

7 (References on following" page) 5 REFERENCES CITED Number The following references are of record in the 981,310 file of this patent: UNITED STATES PATENTS 5 Number Name Date Re. 15,865 Misner June 24, 1924 Number 268,541 Roystone Dec. 5, 1882 9 ,63 548,272 Robischung Oct. 22, 1895 1 2, 49 760,926 Schroeder May 24, 1904 10 7 ,5 980,654 Mason Jan. 3, 1911 7 Name Date Sterling Jan. 1 1911 Roberts Apr. 5, 1921 Hohnhorst et a1. June 4, 1929 FOREIGN PATENTS Country Date Austria Jan. 10, 1923 Switzerland Dec. 1, 1923 Great Britain Feb. 23. 1922

Images