US2453748A

US2453748A - Surfacing runner

Info

Publication number: US2453748A
Application number: US739720A
Authority: US
Inventors: John M Fisher; Merle M Eakins
Original assignee: Pittsburgh Plate Glass Co
Current assignee: PPG Industries Inc
Priority date: 1947-04-05
Filing date: 1947-04-05
Publication date: 1948-11-16
Anticipated expiration: 1965-11-16

Description

Nov. 6', 1948.. A .1. M. FISHER ETAL 'l 2,453,748 y l SURFACING RUNNER i Filed April 5, 1947 2 sheets-sheet l J. M. FISHER ET AL 2,453,748 SURFACING RUNNER Nov. 16, 1948.

Filed April 5, 1947 fida/.3. y 3l 2 Sheets-Sheet 2 32 /fv EN Toes n f 1/0 Mv /vz Fisk/5e m TTOE/VE'K Patented Nov. 16, 1948 UNlTEDjs/TfATEs PATENT OFFICE f' "2,453,743 A l j sURrAcING RUNNER o Jaim M. Fisherjand Merle M. Ekins, Ford city,"`

Pa., assignors to Pittsburgh Plate Glass Company, Allegheny Count VPennsylvania y, Pa., a corporation of Application April 5, i947, serial No. 739,720

s claims. (ci. 51-2o9i This invention relates to apparatus. for surfacing sheets of glass, or the like, and it has particular relationl to a .bonded abrasive unit `and mountings therefor. j f

One object of the invention is to provide an improved mountinglfor bonded abrasive surfacing units by which a unit can be firmly lheld over a greater portion of .its area while in application toworktobesurfaced.

Another object of thev invention is to provide an improved structure and` arrangement of a chuck and bonded abrasive elements adapted to be mounted upon a surfacing machine.

Another object ofthe invention is to provide improved mountings for bonded abrasive ele- Inents by which rigid connections are uniformly distributed over the abrasive elements to prevent inequalities in stresses and by which portions of the connections can be removed according to the degree of wear on the work-engaging` surface of the abrasive elements.` I

In the drawing: y l

Fig. 1 is a diagrammatic bottom` plan of a runner unit for a surfacing apparatus; Fig. 2 is a fragmentary horizontal section, on .a larger scale, taken substantially along the line II-II of Fig. 4; Fig. 3 is ajfragmentary cross-section', on a larger scale, taken substantially-along the line III-III of Fig. 1; and Fig. 4 is a fragmentary side elevation of a runner unit. j z

In one form of the inventionillustrated,inthe drawing, an annular runner assembly I I3 comprises a metal disk cap lII that is adapted to beY connected to a runner supporting mechanism of a surfacing apparatus, and an annular groove I2 is formed inthe lower side of the disk. cap adjacent `its rim. A segmental` annular abrasive structure I4 composed of bonded abrasive segments I5 has the upper edge portions thereof ittedinto the groove I2 while the lower edges or rim portions I6 remain free to` engage work to be surfaced. The assembly of abrasive segments I5 defines an annulus of substantially truncated conical form. Suitable cement Il secures the upper rim portion of the annularabrasive structure I4 firmly in the groove I2. `The surfacing segments I5 can be selected, as to composition,

from Well known types of bonded abrasive used in surfacing operations according to the nature of the work to be surfaced.

Although the position of the runner assembly as shown in the drawing is such that the axis of the annular structure I4 is' substantially vertical or upright, it is to be understood that such position `is illustrative for purposes of convenience in descriptionY and thatthestructure is adapted to operate in other positions.

position for LIn order `that the abrasive segments I5 may be mounted and held in proper position to form an annular structure, al-series of truncated conical metal rings I8, I9 and 20 of unequal diameters are rigidly secured to these segments by means of horizontal bolts 2| arranged radially of each ring. The rim portions of the rings are rabbeted, as indicated at 22, for they purpose of insuringicontinuity of the conical surfaces of the` rings along the joints defining the lines of division between adjacent rings and inconformity with the "contour of the innerV walls of the segmentalannular structure I4. Thethree rings thus constitute `sectional ring structure. The smaller or upper ring I8 is disposed at its upper edge in anannular groove 23 formed in the lower side ofthe disk` cap II. The annular grooves I2 and 23 are'arranged `so as to be coaxial with each other and with respect to the annular structure I4 and rings I8, I9 and 20.

The bolts 2I are screwthreaded into tapped openings 24 in the rings` which have lugs 26 welded thereto, as indicated at 21, to v insure proper depth of the tapped 3 openings. These bolts are spaced `circumferentially along each ring and disposedradially thereof.

The adjacent edges of the successivesegments I5 are spaced sufficiently toreceive rows of the boltsv l2l that are connected to the rings I8, I94

to the extremitiesof theabrasive segments which v might otherwise contact the bolts during assem- `ings 36 in the `central bly ofthefsegments or during operation of the runner assembly. The outer ends of the bolts are provided with clamping heads 32having converging outer walls 33 which are coinplemental` tosimilar converging or beveled end walls or` faces 34 of the segments I5. The clamping heads 32 arevrecessed, as indicated at 35, to `receive the heads of the bolts in countersunk relation.`

The Shanks `of these bolts extend through openportions ofthe clamping heads.` This arrangement of elements isdesigned kfor the purpose of l preventing any projections beyond the outer circumferential surfacesof the abrasive` segments. Suitable gaskets 3l composed `vof` yieldable material, such as ilber composition, rubber composition, or the like, are disposed` between opposed complemental faces 33e-34. By tightening the bolts 2I in the metal rings the surfaces 33 of the vclamping headsy 32 of the segments I5 and against the cushioning ansah-is gaskets 31. The several inner faces of the segments I5 at locations on opposite sides of the respective bolts 2| are also cushioned by means of gaskets 38 disposed between the segments I5 and the surfaces of the rings.

It is to be noted that the bolts 2I are disposed radially at points spaced circumferentially of each ring. After th'e abrasive segments have been a truncated cone, and means for demountably worn a predetermined degree in their oper-ation,

the lower ring can be removed by releasing the bolts connected thereto, Upon releasing these bolts the ring is free to fall from the conical or flaring inner walls of the annular structure I4. In like manner, the next ring I9 is adapted to be removed after the segmental abrasive structure has been worn along its lowerrim to such extent th'at it is nearing the edge of such next ring I9. In this manner the segments I5 can be firmly mounted with respect to the rings and supporting disk II, andthe several rings can beA successively removed according to the degree of Wear on the surfacing rim, While still maintaining proper rigid mounting and distribution of stresses in the annular abrasive structure.

rIt is i-mportant that the segments be cemented firmly to the disk cap II. The bond between the abrasive segments I5 and the metal disk in the groove I2 can be effected by cementing with such materials as pitch, Roses metal (an alloy of bismuth, lead and tin) type metal or other eutectio alloys or magnesium oxychloride.

Although only one form of the invention has been shown and described in detail, it will be apparent tothose skilled in the art that the invention is not so limited, but that various changes can be made therein without departing from the spirit or scope of th'e invention as exemplified in the appended claims.

We claim:

1. In a runner assembly for surfacing apparatus, a runner cap of plate form, a ring connected edgewise upon the bottom of the cap, additional rings disposed in coaxial relation to the rst ring, adjacent rings having rim portions overlapping in axial directions and having their wall surfaces substantially ush with one another, bonded abrasive material defining an annular contour and arranged in coaxial relation to the rings, each ring having a series of connections spaced at intervals circumferentially of th'e ring and securing the ring and abrasive material in rigid relation.

2. A surfacing assembly comprising a supporting member, said member having coaxial grooves in one side thereof, ring structure having a rim disposed in one of said grooves and leaving an opposite rim free, bonded abrasive material defining an annular contour and mounted in the other groove, said abrasivematerial including a surfacing rim extending axially beyond the free rim of the ring structure, and radial connections Securing the annular abrasive material and ring structure in rigid relation.

3. In a runner assembly for surfacing apparatus, a supporting cap having an annular groove on one side thereof, bonded abrasive material of annular form having an upper rim thereof mounted in said groove, rings disposed coaxially in edge to edge engagement and coaxially of the annular abrasive material, and means for demountably securing the rings separately to the annular material, said rings having intertting edge to edge engagement holding adjacent vring edges against relative lateral displacement, and being successively removable therefrom.

connecting each ring section to the abrasive sections, adjacent marginal portions of said sections having interlocking means holding them against relative lateral displacement and said sections being free to fall axially from one another upon release of said means.

5. In a rotatable runner assembly for surfacing apparatus and having an upright axis, a supporting cap having inner and outer coaxial grooves on the lower side thereof, a bonded abrasive seg-mental annulus composed of segments defining a surfacing rim disposed in a plane transversely of the axis of the annulus and anchored in the outer groove, said segments being disposed successively about the circumferential extent of the annulus, adjacent segments having converging wall portions, metal ring structure interfitting in coaxial relation with the segmental annulus in axially spaced relation to the surfacing rim and having its upper rim anchored in the inner groove, said ring structure including ring sections with adjacent marginal portions of the sections in assembled relation being interlocked against lateral displacement, each ring section having radial openings therein registering with the lines of division between the several segments, and fastening means separately mounted in the openings of each ring section and having portions disposed in wedged relation on said converging wall portions to secure in rigid relation the annulus and ring structure.

6. In a runner assembly for surfacing apparatus, a segmental annulus composed of bonded abrasive segments defining a surfacing rim disposed in a plane transversely of the axis of the annulus, adjacent segments of the annulus having oppositely beveled and juxtaposed extremities, metal ring sections interfltting in coaxial relation with the annulus1 adjacent marginal portions of the rim sections in assembled relation being rabbeted and interlocked against lateral REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number v Name Date 508,773 Shipe Nov. 14, 1893 1,587,534 Lipps ai June 8, 1926 1,611,747 Heppenstall Dec. 21, 1926 1,797,526 Hoaglund Mar. 24, 1931 FOREIGN PATENTS Number Country Date 190,028 Great Britainl Dec. 14, 1922