US2067089A - Yieldably mounted abrasive elements - Google Patents

Description

Jan. 5, 1937 H. P. KIRCHNER .YIELDABLY MOUNTED ABRASIVE ELEMENTS Fild May 22, 1954 2 sheets -sheet 1 INVENTOR. Y P KIRGHNER ATTORNEY.

Jan. 5, 1937. H. P. KIRCHNER 2,067,089

YIELDABLY MOUNTED ABRASIVE ELEMENTS Filed May 22, 1934 2 Sheets-Sheet 2 gutgiui INVENTOR. HENRY F? KRGHNER ATTORNEY.

Patented Jan. 5, 1937 UNITED STATES YIELDABLY MOUNTED ABRASIVE' ELEMENTS Henry P. Kirchner, Niagara Falls, N. Y., assignor, by mesne assignments, to The Carborundum Company, Niagara Falls, N. Y a corporation of Delaware 8 Claims.

plurality of extended abrasive edges and a plurality of abrasive surfaces which extend over large areas.

My improved device is illustrated by the accompanying drawings in which:

Figure 1 is a side elevation of a belt and abrasive carriers with some abrasive elements or blocks in position thereon, the fastening means being only slightly indicated;

Figure 2 is an enlarged transverse section taken on the line IIII of Figure 1 and showing fastening means for the abrasive carriers in more detail;

Figure 3 is a transverse section of a modified abrasive block and mounting taken in a plane at right angles to that of Figure 2 and showing a more extended base than is shown in Figure 1;

Figure 5 is a plan view of abrasive carrier showing means for attaching the carrier to a belt at the center of the carrier as well as at the ends; 1

Figure 6 is an end view of a modified form of carrier and abrasive element in which the element is cemented in the carrier;

Figure '7 is a side view of a portion of an abrasive belt in which the flexible support is .made up of leather links;

Figure 8 is a plan view of a portion of the abrasive belt shown in Figure the view being directed toward the working surfaces of the 5 abrasive elements;

Figure 8A is a view of the opposite side of the abrasive belt shown in Figure 8, the view being directed toward the surfaces of the links which contact periodically with the driving pulleys;

Figure 9 is a. plan view illustrating possible arrangements of abrasive elements on a supporting belt;

Figure 10 is a plan view of still another form of abrasive carrier and attached element;

5 Figure 11 is a side view of the carrier and Application May 2 2, 1934, Serial No. 726,960

abrasive element indicated in Figure 10, the method of attachment to the belt being also shown;

Figure 12 is a transverse section of the element and carrier .on the line XIIXII of Fi ure 10;

Figure 13 is a fragmentary side elevation of an abrasive or polishing wheel in which the abrasive carriers and associated abrasive elements are attached to a hub in a manner similar to the belt attachment shown in Figure 7; I

Figure 14 is a fragmentary side view of a modified abrasive wheel in which the carriers and associated abrasive pieces are set in slots in' a wheel hub and are yieldably held against centrifugal displacement;

Figure 15 is a. section on the line XV-XV of Figure 14;

Figure 16 is a fragmentary side elevation of still another modified abrasive wheel in which the abrasive elements and their carriers are yieldably held on a felt rim which is carried by a rotary hub; and a Figure 17 is a section on the line XVIIXVII of Figure 16.

Referring to the drawings in detail, there is shown in Figure 1 a belt 2 which may be made of canvas, leather or fiber. The belt shown in Figure 1 is mounted on pulleys 3, 3. One of these pulleys may constitute the driving pulley and the other the driven pulley. Means not shown can also be used for moving the pulleys further apart or closer together to vary the tension of the belt. On the belt 2 are mounted a number of similar abrasive elements 4. The abrasive elements 4 are supported in metal holders or carriers 5. These members 5 can be formed from sheet metal by stamping and pressing into channel form with extensions for fastening to the belt as required.

In Figure 1 the upper edges of the carriers are shown as turned inwardly to give the carrier a better grip on the abrasive element. The abrasive elements can be slipped into or out of the carriers through the ends of the channels. They are therefore renewable. As shown in Figure 2, 1ugs are provided by means of which the holders F are extended longitudinally with respect to the abrasive elements. Bolts 1 and nuts 8 are used to fasten the lugs 6 (and consequently the abrasive elements) to the belt. The pulley rim is made narrower than the belt so that the rim does not contact with the heads of the bolts 1 or the heads are sunk in the belt to avoid jarring contacts with the pulley rim hold the abrasive member in the holder.

- just mentioned, shellac may be used. This is cured at a temperature of about 350 F.

The abrasive member can be made with a broadened base as shown in Figure 3, the acute lower edges helping to anchor the abrasive member in the carrier which is shaped to resistoutward movement of the abrasive member. The base of the carrier 9 is curved to assist the passage of the carriers, and the abrasive elements which they support around the cylindrical sur- ,faces of the pulleys. When the abrasive elements 4' have become worn down the edges of the carrier l0 can be pried outwardly sufliciently to permit the removal of the worn element 4' and its replacement by a new one.

The abrasive carrier may be bolted or riveted to the flexible support at the center of the carrier or at other convenient points along the carrier base as indicated in Figure 5.

In the modification .illustrated in Figure 7, leather links I3 are mounted on rods l4. These rods are threaded at one or both ends and nuts l5 are used to hold the assembly of leather links together. The abrasive carriers I6 are rotatable on the rods Id. In actual practice the abrasive elements come closer together than is indicated in Figure '7 and support each other at times by lateral contact. When an abrasive element H has become worn down (and if it is desired to replace such worn element) the clamping edges of the carrier l6 can be pried outwardly to permit removal of the worn element l1 and its replacement by a new element. The leather links are somewhat resilient or flexible in character and give a certain amount of resilience. It will be noted that in this modification each abrasive element is flexibly mounted- End clamps 18 can be used to hold the abrasive elements I"! against longitudinal movement in their carriers l6.

Instead 'of attaching the abrasive carriers to the belt at the edges of the belt, the carriers can be fastened (by methods described above) at points removed from the edges. Abrasive elements can thus be distributed in various patterns over the face of the belt as indicated diagrammatically in Figure 9. The abrasive elements are shown in this view in staggered relationship to avoid as much as possible streak marks on the work. The arrangement oi'the abrasive members is such that thelonger abrasive edges act princi-, pally on thework. The long channels make it comparatively easy to dispose oi! debris.

In the forms of abrasive carrier indicated in Figures 10, 11 and 12, the abrasive element 2| is cemented as at 21 in a metal holder 22. This holder has side flaps 23 and end flaps 24 which can be pried loose from the sides and endsoi the abrasive element when it is desired to renew the latter, the residue of the abrasive material being chiselled from the base. The holder or carrier can be attached to the belt by means of bolts and nuts as indicated at 25. A screw may be acevpsa used to hold the central portion of the carrier to the belt as indicated at 26.

In Figure 13 there is shown a form of abrasive or polishing wheel in which the grinding or polishing elements 3| are mounted in carriers 32 which are adapted to oscillate on rods 33 which are in turn supp rted in the hub 34. The abrasive elements 3| are supported in their carriers 32 in a manner similar to that shown for the abrasive elements indicated in Figure 7. Such an abrasive wheel is adapted to the grinding or polishing of certain types of uneven surfaces and has certain advantages over a rigid abrasive wheel. One of the particular advantages lies in the fact that a worn abrasive element can be easily renewedp In the modification shown in Figures 14 and 15 the abrasive elements are also easily renewed. The abrasive carriers 42 are set in recesses 43 of a rotary vhub. The abrasive carriers are provided with terminal hooks 44. An endless resilient member 45 (consisting for example of a continuous helical spring) is supported on the hooks 44 and resists the tendency of the abrasive element to move outwardly when the wheel is in rotation.

In the modification shown in Figures 16 and 1'7, the abrasive carriers 52 are supported on a felt rim 53 which in turn is supported on the peripheral surface of a rotary hub. Resilient members 55 are used to hold the abrasive carriers 52 against the felt rim 53 in a manner similar to that described for the extensible members 45 shown in Figures 14 and 15. The felt rim gives a softer grinding action than is obtained when the abrasive carriers are supported on a rigid surface.

The abrasive members can be made in large numbers by means of briquetting machines, using standard abrasive mixes containing abrasive grain and a bond that can be hardened by one or more of the usual methods, for example by heating. For rapid grinding of metal surfaces, silicon carbide or fused aluminous grain of comparatively large grit size is desirable. As compared with grinding operations by means of abrasive wheels a number of diiferences'are to be noted. These difierences affect the character of the bond to be used for the abrasive grain. In the applicant's apparatus the abrasiveeffects depend more on impact action than is the case with abrasive wheels. In the applicants PDa-mtus, the leading edges oLthe abrasive members sustain repeated shocks by successive contacts where the travelling belt is passing over a rough surface. Hence a tough bond suchas shellac has some advantages over a clay or glass bond, since a clay or glass bond is more brittle.

As compared with the usual form of sanding belt my abrasive belt allows much more clearance for debris donned by material removed from the work and from the grinding device. Abrasive elements are easily replaced since they can be supplied already mounted in their metal carriers and attached to the belt by bolting or by other simple clamping means.

As has been suggested above, many different kinds of abrasive grain may be used in tomiing of abrasive carriers each of which is rotatably mounted on a single one of said rods, and rigid abrasive elements clamped in said carriers, each element being held at a constant distance from the rod that supports its carrier.

2. An abrasive device comprising an endless belt composed of links which are mounted for relative movement on parallel rods, a plurality of abrasive carriers each of which is rotatably mounted on a single one of said rods,,and rigid abrasive elements clamped in said carriers, each of said-links being'composed of a flexible material, I

3. A flexible abrasive article adapted to be driven by a pair of cylindrical pulleys mounted on parallel shafts, said flexible abrasive article comprising an endless belt containing parallel rows of links of light strong material, transverse rods in said belt each of which passes through a link in each row, consecutive parallel rods being connected by links in alternate rows, a plurality of abrasive carriers each mounted for limited oscillation on one of said rods, and a rigid abrasive block clamped in each of said carriers.

4 A flexible abrasive article adapted to be driven by a pair of cylindrical pulleys mounted on parallel shafts, said flexible abrasive article comprising an endless belt containing parallel rows of leather links, transverse rods in said belt each of which passes through a link in each row in a direction parallel to the driving shafts, consecutive parallel rods being connected by links in alternate rows, a plurality of abrasive carriers each mounted for limited oscillation on one of said rods, and a rigid abrasive block clamped in each of said carriers by clamping means which contact with the sides of said block adjacent its base.

5. A flexible abrasive article adapted to be driven, by a pair of cylindrical pulleys mounted on parallel shafts, said article comprising a belt containing a series of rows of links of light strong material, each of said links having a high coefficient of friction on. its edges and the links in any one row being offset a half link with respect to the links of an adjacent row, a series of transverse metal rods in said belt for interconnecting a plurality of links, an abrasive carrier rotatably mounted on each rod, and an abrasive block mounted in each of said carriers, said blocks being similar in shape and presenting outer surfaces which are approximately parallel to the direction of motion of the adjacent portion of the linked belt.

6. An endless abrasive belt comprising a plurality of rows of links arranged in parallel planes, each row contacting with the same driving pulley and the same driven pulley, a plurality.

of transverse rods each of which passes loosely through a terminal portion of a link in each row but through oppositely extending links in the 'case of adjacent rows, and a bar of bonded abrasive mounted for oscillatory movement about each rod as well as for continuous movement with the belt.

7. A flexible abrasive device comprising an endless belt composed of links which are mounted in a plurality of parallel rows for successive motion by engagement with a pair of pulley wheels, a plurality of abrasive carriers each mounted for limited movement on a rotarysupport that passes transversely through a plurality of said links, and a rigid abrasive element 7 clamped in each bf said carriers.

8. A flexible abrasive device comprising an endless belt containing links which are mounted in a plurality of parallel rows for successive movement by engagement with a pair of pulley wheels, aplurality of abrasive carriers extending transversely of the belt outside of said links, each of the carriers being mounted on a rotary support that passes transversely through a plurality of said links, and a rigid abrasive element. mounted in each of said abrasive carriers, the abrasive elements having bases of larger area than the outermost grinding surfaces whereby an abrasive element can be retained against outward movement by flanges on its carrier which converge toward the working surface of the abrasive element.

may P. KIRCHNER.

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