US2487406A - Mechanism for crush dressing grinding wheels - Google Patents

Description

Nov. 8, 1949 M. H. ARMS ET AL 2 sheets-sheet 1 Filed July 26, 1945 Nov. 8, 1949 M. H. ARMS ET AL MECHANISM FOR CRUSH DRESSING GRINDING WHEELS 2 Sheets-Sheet 2 Jiw 22/" fiwfwg/Mzw 4g lf ljzywiwzai M WW6 I (/7 Patented Nov. 8, 1949 MECHANISM FOR CRUSH DRESSING GRINDIN G .Merton H. Arms, Springfield, Vt, an'd'Walter "J. Augustenovich, Kansas City, Mo., assignors to Bryant Ghucking GrinderCompany, Springfield, Vt., a-corporation of Vermont Application July 26, 1946, Serial No. 686,4.08

7 Claims.

, This invention relates to the dressing of grind-' ingiwheelslby crushing.

'One'o'bjectisto provide a dressing mechanism well adapted for use onxgrindingwheels'having portions .of substantially different diameters, avoiding the rapid wear of the crushing rolls caused by substantial'relative slippage between certainportionsof the'roll and the wheel where suc'h'diameter differences are substantial.

Atfurther objectisto provide for positive rotation of atleast'a portion of "the crushing roll which "is in contact 'with the wheel, the wheel being rotated bythe rotated crushing roll, or, if desired, positively rotated at 'a'relatively low speed.

Still "another object is to provide 'an improved mounting and drive "iorthe crushing roll with mechanism to move the prolliinto and out of crushing position.

Further objects and advantages will appear from adescription of certain embodiments of the invention shown inthe-accompanying draw ings in which Figure 1 is a fragmentary plan view of the upper portion of a grinding'machine showing mechanism embodying the invention.

Figure 2is aside elevation'of thesame mechanism, a portion "of the grinding machine frame being shown in section.

"Figure 3 is a detail sectional view on line '3-3 of Figure 1.

Figures 4 and'5 are'centralcross sectional views showing two constructions of crushing rolls'eith'er of which maybe "employed to crush dress a grinding Wheel'tothe'same contour.

Referring first to Figure 2,'at l is shown portion of the frame of a grinding machine, suitably supporting for rotation at spindle 2 (see Figure 1), to which a grinding wheel 3 is secured. Itwill be 'noted that this grinding wheel comprises two grinding surfaces axially separated. One of these, at 4, is a cylindrical surface, and the other, at '5, hasa convex periphery; They may be two separate grinding wheels with 'a spacer between them rather than a single wheel, if =:desir.ed. The .mean diameter of the convex periphery portion Eris substantially smaller than the diameter of the-portion 4.

The frame *i also has fixed thereto, a plate 6 which is shownas arranged in .ahorizontalplane. To this plate is secured a bracket 1, the securing means .comprising screws .3 .passing through a flange 9 .of the bracket and entering into threadedholes in the plate .6. Theholes through the bracket flange ,9 may be'larger than the bolts suificiently to permit a horizontal-adjustment of the bracket I. As shown this adjustment is effec'tedby turning a screw Ill threadedv into the bracket land'journaled in a bracket l l extending upwardly of the'p'late'fi.

"This bracket 1 has a pair of spaced bearing flanges l5 .at its rear end for pivoting between them a support .20, theipivot being at the trimnions l9. This support '20 carries thereon :a motor 2|, the shaft of this motor being connected through adriVing'beItJZZ with a'belt pulley 23 fixedto a shaft '24, journaled ina casing 25 carried by the support .20.

This shaft! is'connected by a train of gearing, including the gears "26 carried on the shaft 24 and algeari'l carried on a spindle V28 journaled in a casing 29 carried'iby the support20. This spindle 28, in turn, carries the crush dressing roll, indicated generally at30. "The spindle 28 is shown as extendedthrough .a disk 3| forming one element of a labyrinth packing which prevents foreign material from gainingaccess to the bearings supporting the spindle '28.

"Thesupportlil is connectedby a link pivoted at one end thereto to'a piston rod136 which enters a suitably hydraulic power cylinder 3i where it is provided with the'usual piston (not shown).

In the position'of'the parts shownin Figure '2, the piston'36 is inits upper position, holding'the support in the position to 'presentthe crush dressing roll'30 into contact with the grinding wheel 3. By introducingcfluid underpressure into the upper end of the cylinders! by any suitable means (not shown), this piston, may be driven downwardly, rocking the forwardend of the supporttlllupwardly and removing the crushing-roll from contact with thegrinding wheel.

necessarilymather small, and differences in diameter between different portions have corresponding-1y greater relative importance than in large diameter wheels in connection with the subject matter of this invention. The feed between the crushing roll and the wheel is accomplishedfby the usual feed mechanismof the of complemental diameters to that of the wheel,

slippage must take place between some portion of the wheel and the crushing roll, and such slippage is effective in producing a grinding action of the grinding wheel on the roll which seriously shortens its life.

In-Figures 4 and 5 constructions of crushing wear. ing roll is a multipart roll, comprising a body 58 having a central bore 55 shaped to engage the outer end of the spindle 28, which in this instance is shown as, tapered and of such an angle that the body portion 58 may be held tightly for rotation by rotation of the spindle 28. This body portion 58 has a crush dressing periphery 55 for a portion only of its axial length. At another portion of its axial length, the body is of reduced diameter to form a journal portion 55 coaxial with the crushing surface 55 and coaxial with the bore 5|. Journaled on this portion 55 is a ring 58, and in order to hold this ring 58 in journaled position, a retaining ring 59 which overlaps a portion of the ring 58 is secured to the body 55 as by screws 50. It will be noted that the outer face of the ring 58 is of substantially different diameter than the outer crushing periphery 550i the body, and as shown it is larger than that of the body. This outer face or periphery 6! of the ring 58 forms the remainder of the crushing contour of the crushing roll. As shown it is provided with a concavity intended to mate the convexity of the grinding portion 5 of the wheel 3, and of such a diameter that this crushing surface of the ring 58 engages the grinding wheel at the same time that the crushing face 55 engages the portion 4 of the grinding wheel when the grinding wheel is of the size desired.

It will be noted that the crushing roll body is rotated with the spindle 28, and when its surface 55 is brought into engagement with the surface of the portion :3 of the grinding wheel while neither is rotating and the two are thereafter revolved together, the portion 4 of the face of the grinding wheel will be crush dressed, the grinding Wheel being driven by friction contact with the crushing face 55. This will also tend to drive the ring 58, but as this ring is free to rotate on the body 58, it will be driven, in turn, by its engagement with the rotating wheel portion 5, pressing thereagainst, and at a different rate of angular velocity than that of the body 50 by reason of the different effective diameters of the engaging parts on the crushing roll and the grinding wheel. As shown, for example, the effective rate of peripheral velocity of the grinding wheel portion 5 is less than the peripheral rate of the grinding wheel portion 5, since it is of smaller diameter. Consequently, the frictional drive rate imparted to the ring 58 by its engagement with the grinding wheel will be slower not only because of the slower peripheral effective speed of the grinding wheel portion 5, but also because of the larger diameter of the effective periphery of the ring 58. Thus each of these parts may be driven at a speed best suited to its engagement with the other part, minimizing the drag between the wheel and the roll, and thus 4 minimizing the wear on the roll due to the cutting action of the wheel thereon.

In some cases, as when first dressing a new wheel, the ring 58 may be the only portion of the crushing roll which is effective on the grinding wheel, and where such is the case, with the construction shown, the grinding wheel would not be rotated by the body 50 because its surface 55 would not be in engagement with the grinding wheel. In this case, in order to cause rota tion of the grinding wheel, the ring 58 is temporarily secured to the body 58 so as to be driven thereby thus to impart the necessary rotation to the grinding wheel for the crush dressing. The means for so doing, as shown at Figure 4, comprises a set screw 65 threaded through a bore 66 in the body 50 and provided with an inner end 61 which may be moved into a socket 68 in the ring 58. A friction plug 10 seated in a socket H in the. body 55 and pressed into engagement with the set screw 55, as by a spring 12 in this socket, holds the set screw 55 in adjusted position, either into driving. engagement with the ring 58 or freeing the ring 58 for rotation relative to the body.

In Figure 5 another form of crushing roll is illustrated for operation on a grinding wheel of the same contour as that operated upon by the crushing roll of Figure 4. This construction comprises a body 580. which has a large diameter portion 51a having a crush dressing periphery identical with that of the, ring 58 of Figure 4. It also has a reduced diameter portion 56a on which is journaled a ring 58a,having a periphery 55a the same as the periphery 55 of the body 58 in the construction of Figure 4. The portions of the crush surface on the journaled ring and on the body in this construction are thus reversed from that of the construction of Figure 4. .The ring 58a is ,held on the journal portion 56a as by a clamping ring 59a partly overlapping the ring 58a and held in position by screws 68a. With this arrangement of crushing roll, the grinding wheel is driven by its frictional engagement with the portion 5Ia and the grinding wheel, in turn, drives the ring 55a at a higher rate of speed than is the body 58a. Here, again, if the ring portion is to accomplish the dressing action while the body portion is idle, the ring will be clamped to the body portion so that the ring will be driven thereby. Means for doing this comprises the locking disc 88 which hasa laterally extending externally threaded flange 8| meshing with an internally threaded portion 82 of the body 50a, this disk having an annular shoulder 83 adjacent its peripherywhich may engage against the end face of the ring 5811 so that when the disk is tightened it will clamp the ring 58a against the body 58a.

While as shown the crushing roll is power driven and intended to be used when the wheel is free to be rotated by friction therefrom, the power could be applied to the grinding wheel, but this would be at a much slower rate of speed than the grinding speed. It would then be possible to mount all the different diameter portions of the crusher roll forfree independent rotation, though, if desired, one might be power driven if at a speed correctly related to that of the correspending portion of the grinding wheel for the crushing action.

From the foregoing description of certain embodiments of this invention, it will be evident to those skilled in the art that various further modifications and changes might be made without departing from the spirit or scope of this invention.

We claim:

1. In combination, a rotary shaft, means for rotating said shaft, a multi-part crushing roll carried by said shaft, one part of said roll being supported for rotation with said shaft, another part of said roll being mounted coaxially with said first part for rotation relative to said first part, each of said parts having grinding wheel crushing peripheries, the crushing peripheries of said one and said other part being of substantially different eifective diameters.

2. In combination, a rotary shaft, means for rotating said shaft, a multi-part crushing roll carried by said shaft, one part of said roll bein supported for rotation with said shaft, another part of said roll being mounted coaxially with said first part for rotation relative to said first part, each of said parts having grinding wheel crushing peripheries, the crushing peripheries of said one and said other part being of substantially different effective diameters, and means for locking said parts against relative rotation.

3. A crushing roll presenting a peripheral wheel crushing portion and a journal portion coaxial with said wheel crushing portion, and a ring journaled on said journal portion and having a wheel crushing periphery of substantially different effective diameter than the effective diameter of said crushing portion.

4. A crushing roll presenting a peripheral wheel crushing portion and a journal portion coaxial with said wheel crushing portion, a ring journaled on said journal portion and having a wheel crushing periphery of substantially different effective diameter than the effective diameter of said crushing portion, and means for releasably securing said ring to said roll against relative rotation.

5. A crush dressing roll comprising a body having a bore to receive a rotating spindle and having at a portion of its axial length a wheel crushing periphery coaxial with said bore, and another portion of its axial length formed as a journal 6 part, a ring journaled on said journal part and having at its periphery a wheel crushing portion, and a retaining ring secured to said body and overlapping said journaled ring for retaining said journaled ring on said journal portion.

6. A crush dressing roll comprising a body having a bore to receive a rotating spindle and having at a portion of its axial length a wheel crushing periphery coaxial with said bore, and another portion of its axial length formed as a journal part, a ring journaled on said journal part and having at its periphery a wheel crushing portion, a retaining ring secured to said body and overlapping said journaled ring for retaining said journaled ring on said journal portion, and an element carried by said body and adjustable to engage or to free said journaled ring for releasably securing said journaled ring against rotation relative to said body.

7. A crush dressing roll having dressing peripheries of different effective diameters arranged adjacent to each other for simultaneous dressing action, said peripheries being on separate portions of said roll free for independent coaxial rotation at different angular velocities.

MERTON H. ARMS. WALTER. J. AUGUSTENO-VICH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,440,338 Buswell Dec. 26, 1922 1,513,758 Hanson Nov. 4, 1924: 2,360,127 Hartley et al. Oct. 10, 194-1 FOREIGN PATENTS Number Country Date 465,869 Great Britain May 18, 1937 519,080 Great Britain Mar. 15, 1940 526,075 Great Britain Sept. 10, 1940

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