US2711619A - Buff and core - Google Patents

Description

J. R. DAVIES BUFF AND CORE June 28, 1955 2 Sheets-Sheet 1 Filed July 18, 1949 weep/ Z1? INVENTOR. v ,flzzzzai J. R. DAVIES BUFF AND CORE June 28, 1955 2 Sheets-Sheet 2 Filed July 18, 1949 m w v w m dag z, JP. Zczudes Unite RUFF AND CORE Joseph R. Davies, Chicago, Ill.

Application July 18, 1949, Serial No. 105,362 4 Claims. (Cl. 51-193) buff, it does not necessarily provide thread ends that will hold the butting compound so that it will cross cut all marks on the work that is being buffed. One of the features of applicants invention is a bufiing surface formed of bias cut cloth which lies in a row of reverse folds, that is, a zig-zag appearance as viewed from the side. Additionally, applicant provides a fullness which results in each reverse fold at the working surface being in fact almost a ring, with the result that no matter what the direction of the mark on the work to be buffed may be, the work surface of applicants buff will always provide thread ends that are cross cutting the mark. This may he a little confusing because it is not the thread ends that are doing the cutting, but rather the bufiing compound which is held by the thread ends and which is brought into engagement with the work by the thread ends. Because the thread ends will always cross cut the work, it follows that the compound will always cross cut the work and the result is firstly, that a mark in the work at the time buffing is commenced, will always be buffed out irrespective of its direction, and secondly, because of the cross cutting action, the buff and the compound in the buff will never themselves create a new mark in the work.

These circular or elliptical rings at the working surface 7 are also advantageous in that they hold the bufling compound very well.

Another object of this invention is to provide a cross sectional configuration to the bufiing swatch which will assist in radial circulation of air with consequent cooling. Any advantage that a particular buff may have so far as length of life or thoroughness of the work performed may be lost if the structure does not properly cool the buff at its Working surface. A bufiing compound is formed of abrasive material held together by a lubricant. These lubricants break down under excessive heat and cease to function properly. The abrasive is released from the compound and if the heat gets sufficiently high, the working face of the buff itself is scorched. A feature of applicants invention is the use of what might be called a double pleating arrangement of the fabric at the inner edge of the buff. Applicant pleats a double thickness of fabric along one edge to form an annular sector and then he zig-zags the inner edge of this sector around a central disc to form what roughly resembles a fan. No matter'how tightly this type of buff swatch is compressed at'its inner edges, there are primary and secondary side for certain kinds of materials.

7, 2,711,619 Patented June 28, 1955 openings which tend to pick up air and force it outwardly.

Another object of this invention is to provide a working face on a bulf whose density may be adjusted by varying the RPM on the core. The firmness with which a bufi presses a compound against work must vary in accordance with the physical properties of the work. A buff with a very hard working face may be wholly unsuitable Applicant recognizes that the width of the working face of a loose buff can be narrowed or broadened in accordance with the centrifugal force developed, which varies directly with the RPM. One of the features of applicants invention is a buff having reverse folds with their surfaces roughly parallel to the axis about which they revolve but which folds are much narrower near the supporting core than they are at the periphery, with the result that centrifugal force has a flaring work surface which it'can pull into a narrower track, making the buff working surface more dense as the RPM increases.

The final object of this invention is to increase the life of bias buffs by making it possible to expand a buif whose circumferential surface has been contracted by use to a point where its surface is much more dense than originally. At the present time, a bias buff which necessarily has pleats on its inner edge, and which may have an annulus Width of perhaps four or five inches, becomes somewhat worthless after two and one-half inches have been worn down because of loss of peripheral speed (where lathe has constant speed) and because its fibers are more compact closer to the center. These buffs are commonly thrown away, although some manufacturers operate them at accelerated speeds. Applicants buff unit or huff swatch is mounted on a wire having a length equal to the circumference of a core having a diameter of perhaps six inches. This buff may have an annulus thickness of perhaps four inches. After the buff has been worn down by two or two and one-half inches, it is then placed on a core having approximately twice the circumference of the first core, in conjunction with another similarly worn buff, thereby creating a butt unit having a peripheral work surface that moves at approximately the same speed as the surface of the original single buff unit.

There are several less important objects which will appear in the description that follows. The specific construction of the core makes quick assembly possible and the core being a stamping, is inexpensive to make. Applicants butting swatch or unit is mounted on a wire having hooks at each end. An embodiment of the invention is illustrated in the accompanying drawings, wherein:

Fig. l is a swatch of bias cut cloth folded once along a median line to form a rectangular swatch;

Fig. 2 illustrates the step of double stitching, by a sewing machine pleater or gatherer, the folded edge of the swatch of Fig. 1;

Fig. 3 shows the further step of registering a plurality of pleated sectors such as that in Fig. 2, and additionally, stitching them into what is here called a buff swatch;

Fig. 4 shows one end of a buff swatch in perspective mounted on a wire;

Fig. 5 shows a side elevation of a new buff swatch mounted on the small diameter core with the locking plate removed;

Fig. 6 is a view taken on the line 6-6 of Fig. 5;

Fig. 7 is a perspective, exploded view of the locking assembly and locking plate in part illustrated in Figs. 5 and 6;

Fig. 8 is a plan view of two of applicants worn buff swatches positioned on a large diameter core;

Figs. 9 and 10 are plan and perspective views of an alternatively constructed core and wire locking member; and,

the swatch 16 into an annular sector.

Figs. 11 and 12 are edge views of the swatch, Fig. 11 showing its configuration at rest and Fig. 12 in motion.

Continuing to refer to the drawings, in Fig. l, the numeral identifies a strip of bias cut cloth which has been folded along its median line 12, and which has then been run through the pleater or gatherer of a commercial stitching machine along the stitch lines 14 and 16 of Fig. 2. The result of this operation is to gather the fabric along the folded edge 12 so that it is possible by flattening out the unpleated edges 18 and 29 to form The degree of gathering of the pleats, bearing the numeral 22, will determine the inside radius of the annular sector, given a selected width dimension 24-. It is evident that by increasing the length of the swatch 10 in Fig. l indefinitely, and running it through the stitcher pleater, applicant can produce a spiral buff swatch of a selected diameter. However, as will appear more clearly hereinafter, a pleated buff swatch formed in this manner will not provide the advantages that applicant seeks.

Applicant, therefore, limits the length of the swatch 10 to a length such that the curvature caused by the stitching illustrated in Fig. 2 does not produce an unwieldy swatch. He then imposes a plurality of swatches 10, one upon the other in registration, as illustrated in Fig. 3, until he has a desired thickness. He then again stitches along a line such as 26 and then cuts through holes 28. At intervals he cuts out portions of the folded pleated wall at 31 and 33. Grommets 29 may be used in each hole 28 in order to prevent tearing.

With the annular sector switch thus formed, applicant threads the holes 28 over a wire frame 3%), see Fig. 4, the swatch being folded in reverse as illustrated in Fig. 4. The wire frame 30 has hooks 32 and 34 at each end, see Fig. 5. This unit as described, is the unit of sale. The cores hereinafter mentioned may be repeatedly used by the customer.

In Figs. 11 and 12, applicant shows edge sectional elevations of applicants bufling swatch, at rest and at high speed. When the buff is stopped as illustrated in Fig. 11,

the width adjacent the core at 36 is substantially less than n the width at the working face 33. The reason for this is that the pleats 28 hold the lower edge in less space than the free edges at 38 are held. By crowding the pleated edges along the wire frame 30, there is formed, referring to Fig. 4, in the working face of the buff unit, open-sided rings 40 and 42. These rings as illustrated in Fig. 4, are almost elliptical with the long axis lying in a plane at right angles to the axis of the core. By further compressing and adding fold elements along the wire frame 39, the configuration of the rings will tend to assame the form illustrated by the dotted line 44. The configuration of the rings of buffing material at the working surface of the swatch is, therefore, seen to depend in the first instance, on how tightly compressed are the folded layers over the wire frame 30. turning to Figs. 11 and 12, with the width dimension at 38 established in making the swatch, the centrifugal force will tend to narrow the width of the buff directly with its increase, which in turn varies with the speed of rotation of the shaft. It is, therefore, evident that the density of fiber in the working surface of applicants buff can be made to vary directly with the speed of rotation. In so doing, the cross cutting effect obtained by the opensided ring arrangement will always continue, because the effect of changes in speed will be merely to rotate the axis of the ring cross section by about ninety degrees.

The plate upon which applicants buff swatch is mounted is a stamping 46 having radiating posts 48 each with side flanges 56 and 52. Referring to Fig. 7, each of the facing flanges 50 and 52 carry a slot 54 with outwardly directed recesses 56 and the post 48, which may be called the locking post, carries in its flanges, holes 58 and 60. The buff swatch is mounted in the plate 46 by engaging the end 32 in the seat 56 and the hole 58 and extending the wire through similar slots 54 in the other posts However, re-

and engaging the other end in the flange 50. In doing this, the cutout portions 31 in the swatch illustrated in Fig. 3, are seated over the posts. In order to lock the frame 36 in position, a locking plate 62, see Fig. 7, having a like plurality of posts 64, each with flanges 66 and 68 spaced from each other by a lesser distance than flanges 50 and 52, is superimposed with its flanges nesting, as illustrated in Fig. 6. The core and bulf swatch as thus assembled is ordinarily combined with other cores and swatches into what is ordinarily called a buffing wheel, and they are assembled with means for pressing the buff cores tightly together and holding them keyed to the shaft.

Referring to Fig. 5, air can reach the spaces 72 and 74. Rotation of the core, will tend to throw air outwardly through the hollow posts 48, and consequently, the air will move from the spaces 72 and 74 inwardly between the discs and then outwardly through the posts.

A slightly improved cooling eifect is obtained by cores consisting of plates having the configuration of 76 illustrated in Fig. 9. The wall between each post is concave as at 78, permitting greater movement of air. Additionally, the locking plate posts are equipped with wings 8t) and 82 which tend to tighten the edges of the cutout portion 32 of the swatch on both sides of the post. These wings 80 and 82 are on the locking plate.

Referring now to Figs. 5 and 8, one of the features of applicants buff lies in the combination of a selected length of swatch with two cores, one having a circumference equaling that of the swatch frame 30, and the second having a circumference equaling that of twice the length of a swatch frame 34 In Fig. 5, assume that the buff has been worn down to the dot-dash line 86. At this point, the density of the buffs working face greatly exceeds the density at the original work surface. We may assume that the density has reached a point such that it is no longer useful for the particular work being buffed. The user removes the swatch and places it over one half the circumference of the larger diameter core 83 in Fig. 8. It will be observed that the buff has five cutout portions such as 31 and 33 on its inner edge to accommodate the posts of the smaller core in Fig. 5. These cutout portions are in the inside edge of the annular sector in its fiat condition, that is, as illustrated in Fig. 3, with the result that adjacent to each post on the smaller diameter core of Fig. 5, there is considerably less bufling material than in the zig-zag portions between the posts. When this swatch is placed on the larger core 88 of Fig. 8, only two of the cutout portions, namely, 90 and 92, are used with the result that the pleated portions of the buff between any two posts have an extra cutout portion in them which loosens the pleating, thereby correspondingly rendering less dense the working surface of the buff. In the larger diameter core 88 of Fig. 8, there are two posts 94 and 96 which carry hook locking flanges. In the larger diameter core, two or more worn buff swatches are used. By this arrangement, a user is able to wear a buff down for an additional one and one-half inches, increasing the usefulness of the buff by perhaps fifty to seventy-five per cent. This is due to the fact that in a buff having a pleated inner edge, and formed originally from a rectangular piece of material, the amount of cloth in one radial inch is equal to the amount of cloth in any other radial inch. Referring to Fig. 5, there is just as much cloth between the line 86 and the outer end of one tr m-L ventilated wheel. The amount of cloth radially of each post is less than the amount of cloth for a like circumferential distance between any two posts so that air can more freely work outwardly from the posts. By staggering the posts, applicant in eifect has radially directed air passageways at a large number of circumferential points in an assembled butting wheel. Applicant has run this test on one of his buffs. A smoke-producing means was positioned axially of one of applicants cores, and at about six feet therefrom. The core with buff swatch was operated at buffing speed and in a quiet atmosphere. The smoke moved axially toward the core into the spaces 72 and 74 and then around the inside edges of the posts and out the center of the posts into the buff swatch. It was diflicult to determine exactly what air movements were taking place on the buff surfaces on the swatch. It was clear, however, that the swatch acted as a centrifuge of the air so that the pressure on the peripheral edge of the swatch was less than atmospheric pressure.

'At high speeds, some difiiculty has been encountered with respect to the hooks 32. The tendency is to concentrate the centrifugal pull of the buff on these hooks and unless hardened they may straighten out. Applicant has substituted for the hooks a welded bead or knob on the end. This gives a more positive control, while still being readily removable.

Having thus described applicants invention, what he claims is:

l. A circular buffing unit comprising a plurality of sheets of flexible buifing material having two opposite edges in registering relationship with each other, pleats in each sheet along one of its registering edges so as to create an arcuate shaped buffing unit, successive reverse folds in the inside edge of the buff unit as a whole so as to produce a parallel sinuous configuration in all the sheets of the material and to draw the material into a circular unit, and means lying in a plane normal to the axis of the bufling unit and passing through said folds at right angles thereto for holding them in said sinuous position.

2. A circular butf unit comprising a plurality of sheets of flexible butting material having two opposite edges in registering relationship with each other, pleats in each sheet along one of its registering edges so as to create an arcuate shaped bufling unit,' a row of equally spaced sets of aligned holes through all of the registering sheets adjacent the inner edge of the buff unit, successive reverse folds in the inside edge of the buff unit so as to produce a parallel sinuous configuration in all the sheets of the material with the sets of holes in face-to-face circumferential alignment and with the material drawn into a circular unit, and a wire through the aligned holes for holding the unit in assembled circular relationship.

3. The buff unit of claim 2 wherein a metal grommet is mounted in each set of aligned holes.

4. A circular buff unit comprising a plurality of sheets of flexible bufiing material, each sheet having an elongated shape with its long edges substantially parallel and cut on the bias of the material and being folded down its median longitudinal line with pleats along the folded edges, creating an arcuate shape, said sheets having their edges registered, a row of equally spaced sets of aligned holes through all of the registered sheets spaced closely to the pleated edge, successive reverse folds in the inside edge of the butt unit so as to produce a parallel sinuous configuration in all the sheets of the material with the sets of holes in face-to-face circumferential alignment and with the material drawn into a circular unit, and a wire through the aligned holes for holding the unit in assembled circular relationship.

References Cited in the file of this patent UNITED STATES PATENTS 2,004,623 Yoke June 11, 1935 r 2,061,940 Hargy NOV. 24, 1936 2,099,777 Thomas NOV. 23, 1937 2,106,610 Kreilick et al Jan. 25, 1938 2,130,849 Kreilick et a1 Sept. 20, 1938 2,226,624 MacFarland et al Dec. 31, 1940 2,226,625 MacFarland et al Dec. 31, 1940 2,309,553 Twyning et al Ian. 26, 1943 2,462,741 Hall Feb. 22, 1949 2,468,686 Sax Apr. 26, 1949

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