US2341820A

US2341820A - Art of grinding

Info

Publication number: US2341820A
Application number: US495485A
Authority: US
Inventors: George D Schoger
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-07-20
Filing date: 1943-07-20
Publication date: 1944-02-15
Anticipated expiration: 1961-02-15

Description

Feb. l5, 1944. G. D. 'SCHOGER 2,341,820

ART oF GRINDING Filed July 20, '1943 Ummm,

Patented Feb. 15, 1944 UNITED STATES PATENT lOFFICE ART F GRNDKING George D; Schoger, Anderson; Ind." Application July .20",` 1943, Serial No. 195;485

(Cl. 125-l1`) l@ Claims;

This invention relates to the art of grinding.

The invention is designed more,particularlyforV use in connection with grinders in which the work is carried on-a bed ycapable oi reciprocation andwhich is provided with suitablev headstock and tail stock formations the centers-cf whichv serve to xedly. position the Work relative-to the grinding face. commercial service, and it is apparent that asta result ci such service the-grinding face or faces require dressing at intervals in the form oi.

sharpening or truing, the grinding faces -by the use of a tool or implement `which includes a dressing agency-generally a diamond- Which v is caused to traverse the curved'faceof thegrinding Wheelas *thev latter is rotated.V The `toolis positioned at the mosteicient angle for serv-- ice, and must be xedly held in its adjustedposition during the truing operationwhile traversing the face of the Wheel through the movementof the bed. Where it is `necessaryfto adjust: the i tool each-time it is being ,placed-in position-1, the` time-consuming sinceY the` operation becomes specic adjustment made initially mustzbe Arepeated each time Atheitocl is being repositionedfor dressing service, each truing-operation thusrepresenting a time :expenditure of considerableextent and value' where dressingl is made frequently.v

The present invention` is designed to meet this Ycondition by providinga vunit which, after ithas been once properly adjusted to providef theA dressing operation, can `be removed bodily'asa unit and-v replaced as-needed; since theadjustments are retained Whiletheunitis inactive-.it becomes necessary only. to. replaceV the unit inl its position forservice, and then providefthe; dressing foperation.- The unit is also additional--A ly serviceable fordressing the sides'of'the grind-v ing wheel, thusenablingthe wheel dressing-to include sharpening. Theunit is of simple formation, sturdy in construction, simple as toadjustments, and of durability structurally.,

To these and otherends, the-naturev of whichwill be readily understood as vthe-invention s-l` hereinafter disclosed, said invention consists in Machines.A of. this vtype are in.-

theimproved construction and combinationsof y parts hereinafter described in detail, illustrated in the accompanying drawing, and more particularly pointed out in the appended claims.

In theaccompanying' drawing, in which similar reference characters indicate similar parts in each of the views- Figure -lis a top plan view of the unit of thev invention, certain parts of the grinding mae chine being shown by dotted lines, thus indicating the position ofthe unit during service.

Figure 2 is a side elevation of the unit, with parts broken away, the view also showing machine parts in dotted lines.

Figure 3 is a view, partly in section and partly in elevation of one form oi supporting structure which may be utilized, this supporting structure serving as a part of the unit.

The grinding machine to be serviced isnot disclosed in complete detail herein, but parts thereof are shown by dotted lines. For instance,y

thegrinding wheel is shown at A, with a part of the bed shown aty B, the latter being reciprocable across the face of the Wheel, as indicated by the dove-tail guide b in Figure 2. The bed carries a headstock and a tail stock-the centering points of these are indicated respectively at C and -D-these, during normal grinding operations, supporting the work being ground and which is moved across the face of the grinding wheel by reciprocating bed movements While the wheel is being rotated. There are a numbenof forms of machines of this type, but al1 of them' utilize the above elements as apart of the equipment so that it is unnecessary to illustrate morethan as indicated', these parts having directrelation to the unit operations.

The underlying fundamental of the present-inventionl is presentedby the fact-that the unit is so formed and arranged that it can be substi-` tuted for-the work in the work mounting, anclgbyl preventingv unit rotation While permitting all necessary adjustments, it is possible to properly ad just the dressingtool lrelative-to the wheel, after.

which the unit can beremoved'from andreplaced in position with'the ease and simplicity of a removal and positioning of a succession'of` the Work pieces, the unit adjustments remaining. constant so that the replacementrestores* the conditionsas'to angularity, etc., which' werev provided during f the initial dressing-action, en.- su-ringguniformity in successive dressings.

Specifically, the -unit oriinstrumentality-is'con-' sifructed-oiy a number of 'members ladapted to be "assembled and adjusted relative to each other and to the machine. The main members are the carrier I9 for the dressing tool, an L-shaped element II and a supporting member I2. Member I2 may be an elongated bar of uniform diameter having its ends recessed to cooperate with the head and tail stock centering devices; however, it is preferred that this member be of the adjustable type, provided by two elongated elements I 2a of medium length, each element being provided with the recessed end I2b to cooperate with the centering pin, and the other end formed with an axial recess I2C which is threaded, the threads being formed to receive a threaded connection I2d to permit adjustment in the length of the member; obviously, on the initial positioning of the unit, either end element |20, of the assembly may be rotated to rproduce a desired length of member for use with the particular head and tail stock structures of the machine for which the unit is being prepared to provide the dressing operations. Member I2 is mounted in position on the head and tail stocks, after which carrier I and element II are clamped to it, these structures being provided with opposing notched faces to engage member I2 and position the unit.

The dressing tool carrier I0 is in the form of a block, preferably trapezoidal in form in side elevation and with the top and bottom preferably presenting the parallel sides, and with the bottom side of greater length from front to rear; this lower side carries the V-shaped notch Illa close to its front edge, this notch being designed to overlie the top of member I2. The block IU carries a pair of inclined openings with the openings inclined downwardly from rear to front, the inclination being at a selected angle. These openings are arranged in spaced relation, with the axis of both openings lying on a plane angular to the top and bottom planes of the block. One of these openings I3, is designed to receive the dressing tool for the circular face of the grinding wheel, the opening being internally threaded, while the tool I4 therefor is of extended length and threaded externally, the tool having at its rear end a knurled head Ma by means of which the tool can be readily adjusted lengthwise of opening I3. The forward end of the tool is of the usual type, having a recessed threaded zone designed'to receive the diamond-holding cup Mb, the diamond of which is to provide the dressing of the wheel face. The threaded zone of the tool'carries a lock nut Mc cooperating with the rear face of the block to retain the tool in fixed position during'the dressing operation.

The second opening, indicated at I5, extends parallel with opening I3 and is also screw-threaded. The opening is designed to receive the dressing tool (not shown) used for dressing the side faces of the grinding wheel; tools for this purpose are well known and are of different types. The block carries a set screw I 5a designed to cooperate with such tool to retain it in its xed adjusted position. Since the dressing of the sides of the wheel is only an occasional possibility, the unit is designed more particularly for the dressing of the peripheral face, but is formed to permit of the side face dressing if the latter is required.

-Element II is a structure of general L-shape, being of a flat plate-like form one end zone of which is enlarged laterally to the width of block I0, being narrowed in rear of that zone and bent downwardly at a suitable point, the latter being determined generally by the approximate distance between the axis of member I2 to the rear face of bed B. The upper face of element II is provided with a V-notch I Ia in its forward zone, complementally positioned relative to notch Illa, the walls of the two notches permitting the block I0 and element II to be located in contact with the positioned member I2 carried by the head and tail stock structures, the contact becoming a clamping contact by the use of adjusting bolts I6, positioned at opposite sides of the assembly, and adjusting bolt or bolts I'I-the latter may be single (located midway of the width of the assembly) or double (located at the sides), the latter arrangement being indicated.

Bolts I6 have their stems threaded and extend through openings in element II-but without a threaded engagement with such element-and are threaded into a threaded opening I 0b formed in the block. Bolts I'I are located rearwardly of bolts l, and have their stems threaded and designed to pass through and threadedly engage the threaded walls of openings formed in element II, with the free ends of the stems designed to engage the under surface of block I0. The two sets of bolts thus serve to clamp the block I0 and element II to member I2 and at the same time xedly anchor the lower face of the block and the upper face of element I I in spaced relation, with bolts I6 tending to draw the two together but only as permitted by the positions of the free ends of bolts I'I.

The downwardly-extending leg IIb of member II is designed to overlie the rear of bed B and especially the dove-tail portion thereof. Normally, the head and tail stocks carried by the bed extend upwardly to a position where the work-carried by the head and tail stock centeris properly located as to height relative to the grinding wheel; this places the centers as materially above the top plane of the bed, the distance being dependent upon the particular machine and the position of the grinding wheel axis. Hence, when locating member I2 in the position of the work, the horizontal leg of element I I generally extends rearwardly above the plane of the top of the bed. In practice the work axis generally liespon a horizontal plane extending through the grinding wheel axis, and hence, the substituted member I2 will cause the upper face of the horizontal leg of element II as slightly below such axial plane; since the axis of the dressing tool is located above such axial plane, it is apparent that the pressures developed during dressing, especially those caused by the rotation of the grinding wheel, will tend to rock the unit 0n the axis of member I2 (the ends of which are carried by the head and tail stock centers). To prevent this rocking movement,r the leg IIb of element II preferably carries a pair of bolts I8 and I 9, the former being positioned above and juxtaposed to the top of the bed-preventing material downward swing of element II under such pressures-while bolt I9 is positioned to extend below the lower edge of the dove-tail of the bed, preventing material rocking of member II upwardlywith the free end of the bolt contacting the bed below such dove-tail, the b olt carrying a lock-nut I9a for retaining the bolt in the adjusted position; since bolt I9, due to its contact with the rear of the bed can also serve to prevent rocking of the unit downwardly, it is apparent that the unit will be protected against such rocking movement even though bolty I8 be omitted-such omission is considered within the purview of the invention; however, it is preferred to also employ bolt I8 since it can serve to support the lengthyvhorzontal arm of element II.

I Ib is preferably provided witha plurality of the threaded openingsIIc for bolts I8 and Iii,Y thus enabling the latterto be secured in desired positions with different machines.

In providing the initial adjustments, theunit is accurately adjusted to the particular machine, after which the dressing tool is advanced to the desired point to provide the dressingY action on the peripheral face of the grinding wheel, and the bedvadvanced to carry the tool a-cross the face of the Wheel-if the wheel is movableinthe direction of its axis, the bed remains stationary; if the dressing requirements call for more than one pass of the too-l, the latter is advanced for each additional pass, nut |40 being manipulated each time. After the last pass, hasbeen made, theunt is bodily removed from the machine by manipulating the head and move the centers from the ends of member i2, thus completely freeingthe unit from any positive connection with the machine. The unit is then placed aside in such condition, ready for repositioning when the succeeding dressing is required, at which time it is brought to the machine, the ends of member I2 alined withthe head and tail stock centers and the latter brought into position. It is then necessary only to adjust the tool to take care of any material decrease in dimensions of the grinding wheel, and the dressing operation made active; obviously, this permits the successive dressings to take place under similar conditions as to dressing tool angularity, etc.

As will be understood, the bolts Hand I9- or bolt I9, if used aloneneed not have a cempletely accurate location relative to the edgesof the dove-tail; sincev the length of the horizontal leg of element il is many times that of the,

distance between the axis of member I2 anda vertical plane through the face of the dressing stone, it is apparent that material swinging of the dressing stone about the axis of member I2 can take place only by an extensive swing of the leg IIb in an arc about such axis, so that simple looseness between the screw i9 and the lower edge of the dove-tail may be present without providing any material swing of the dressing stone. Hence, the dressing operation is had under practically steady conditions, .although the unit itself is so arranged as to permit its bodily removal without disturbing any of the unit adjustments-removal and repositioning is provided with the simplicity of the removal of work from and the position ofv work relative to the grinding wheel.

While the above description presents the invention as applied to grinding machines wherein the work is moved relative to the grinding face in the direction of work axis, with the position of the grinding wheel remaining substantially constant, it is obvious that the invention is equally applicable for use with machines in which the grinding Wheel is movable relative to the work additionally to the rotation of the wheel; for instance, the wheel support may be adjustable transverse of the bedthe wheel,vrather than the work being the movable element in bringing the work and wheel face into active relation; or, the work may remain stationary in position, and the transverse and longitudinal movements may be by the grinding wheel. These present various tail stocks to retypesf of the grinding wheel i structuresJ incom-'- mercial use Vin addition to the formaabove discussed.

It is obvious, of course, that the ,inventioniisf applicable for usewith each of the types, since member I2 takes the -position of the workin suoli` machines, and the tool is supported by such. member. Hence, whether the bed is movable1tojward the wheel face, or vice versa, or the wheel. is shiftable axially rather than or additionally:

'to the bed, there is relative movement between 1 the bed, or the work thereon, and thegrinding; face, with the movement provided by one or both of these parts, depending upon theV particular form of the machine. Since the tool is being sube stituted for the work in suchmachines, itis ap,-v

parent that the'tool can be utilizedwith each; of the different types and be operative in accord.` with the normal practice of the machine orfbyy such modications therein as may be found desirable.

As is apparent, the unit, structurally, isof -simple formation, sturdy, efficient inoperation, and@v carries the advantage -above pointed out. AndVl while I have shown a preferred arrangement of the unit, it will ber readily understood that changes or modifications therein may be found desirable or essential in meetinggthe exigencies. of use or the individual desires of the user, and I therefore reserve the right to make any andall such changes or modifications as may be found necessary or essential insofar as the same may, fall within the spirit and scopeof the invention` as expressed in the accompanying claimawhen, broadly construed.

I claim: f

1. In means for dressing grinding wheelsg` wherein the grinding machine is of thetype in i which the work is carried by a bed with the work carried by head and tail stock centers and with., the machine operative to provide relative movement between the work and grinding wheel in a direction parallel to the axis of the grindingz wheel, said dressing means comprising aunit Aor instrumentality formed to support the dressing tool, said unit or instrumentality including a member cooperative with the head and tail stock centers, a dressing tool support and an L-shaped element clamped to the member to thereby definitely locate the unit relative to the grinding wheel peripheral face, said L-shaped element having one of its legs overlying the top plane of the bed and the other leg extending downwardly into overlying relation to the rear face of the b ed, said latter leg carrying an adjusting screw adapted to underlie the dove-tail of the bed and' to contact the body of the bed below the dove-tail, whereby the unit will be held against rotative movement on the axis provided by the mounting of the member on the head and tail stock centers, and whereby the unit is freely removable bodily by release of the member from the head and tail stock centers to thereby retain the initial adjustments of the unit and render the unit available for a succeeding dressing operation on the wheel by restoring the member to its position relative to the head and tail stock centers.

2. A unit as in claim 1 characterized in that the member is adjustable as to length.

3. A unit as in claim l characterized in that the member is formed o a pair of elements each having an end recess cooperative with a stock center and a threaded axial recess leading inwardly from its opposite end, the pair of elements being operatively connected in axial alinement by an interposed threaded element to permit adjustment in the length of the member.

4. A unit as in claim 1 characterized in that the dressing tool support is in the form of a block of trapezoidal form in side elevation, with the block having a threaded bore through which the dressing tool extends and is adjustably mounted, said bore having its axis inclined downwardly from rear to front of the block to thereby present the tool to the wheel peripheral face in direction approximating a radius of the Wheel.

5. A unit as in claim 1 characterized in that the dressing tool support is in the form of a block of trapezoidal form in side elevation, with the block having a threaded bore through which the dressing tool extends and is adjustably mounted, said bore having its axis inclined downwardly from rear to front of the block to thereby present the tool to the wheel peripheral face in direction approximating a radius of the wheel, the angle of inclination of the bore being approximately normal `to the angularity of the rear face of the block to the vertical to thereby permit the locknut of the dressing tool to lock the latter in its adjusted position. i

6. A unit as in claim 1 characterized in that the dressing tool support is in the form of a block of trapezoidal form in side elevation, with the blocking having a threaded bore through which the dressing tool extends and is adjustably mounted, said bore having its axis inclined downwardly from rear to front of the block to thereby present the tool to the wheel direction approximating a radius of the wheel, said block carrying a second threaded bore positioned to permit mounting of a dressing tool for dressing the sides of the wheel.

'7. A unit as in claim 1 characterized in that the dressing tool support is in the form of a block of trapezoidal form in side elevation, with the block having a threaded bore through which the dressing tool extends and is adjustably mounted, said bore having its axis inclined downwardly peripheral face in from rear to front of the block to thereby present the tool to the wheel peripheral face in direction approximating a radius of the wheel, the forward zones of the lower face of the block end of the upper face of the L-shaped element being notched to receive the periphery of the center-supported member for the clamping operation.

8. A unit asin claim 1 characterized in that the dressing tool support is in the form of a block of trapezoidal form in side elevation, with the block having a threaded bore through which the dressing tool extends and is adjustably mounted, said bore having its axis inclined downwardly from rear to front of the block to thereby present the tool to the wheel peripheral face in direction approximating a radius of the wheel, the forward f zones of the lower face of the block and of the upper face of the L-shaped element being notched to receive the periphery of the center-supported member for the clamping operation, the block and element assembly including a screw for directly connecting them in the clamped position and a screw for adjustably ments of the block toward the element.

9. A unit as in claim 1 characterized in that the downwardly-extending leg of the element additionally carries an adjusting screw adapted to overlie the top of the bed in the zone of the dove-tail, said screw together with the rst screw presenting abutments cooperative with the dovetail for preventing rotative movements of the unit about the axis of the member.

10. A unit as in claim 1 characterized in that, the downwardly-extending leg of the element.

additionally carries an adjusting screw adapted to overlie the top of the bed in the zone of the dove-tail, said screw together with the rst screw presenting abutments cooperative with the dovetail for preventing rotative movements of the unit about the axis of the member, said leg being provided with a plurality of spaced openings to permit varied positioning of the adjusting screws to compensate for machine characteristics.

GEORGE D. SCHOGER.

limiting the move-