US2724937A - Buffing wheel - Google Patents

Description

BUFFING WHEEL 3 Sheets-Sheet 1 Filed March 3, 1953 I w N m w w m R Q 8 m 0 e G 0 A W v HTTORNEV Nov. 29, 1955 a, R. CHURCHILL BUFFING WHEEL 5 Sheets-Sheet 2 Filed March a, 1953 I'll" .lll

3 Sheets-Sheet 3 f I I BY I J $4121 QMLLJL' BUFFING WHEEL Filed March 5, 1953 United States Patent BUFFING WHEEL George R. ChurchilLCohasset, Mass.

Application March 3, 1953, Serial N 0. 340,054

4 Claims. (Cl. 51-193) This invention relates to a buffing wheel.

In general, the :object of the invention is to provide a novel construction-of bufling wheel WhiCh is particularly adapted to be used with advantagein producing a superior bufi'ed finish upon certain types of metal and metallic surfaces. I

Another object of the invention is to provide a novel constructionof bufiing -wheel embodying novel bufiing elements and which may be economically manufactured and used with advantage for a wide variety of :bufiing purposes.

A still further object of the :invention is to provide a novel and .practical method by which the present bufiing wheels may be economically manufactured from individual strands of twisted fibers and particularly of twisted sisal fibers, each of relatively small sectional dimension.

With these general .objects in view and such others as may hereinafter appear, the invention consists in the bufiing wheels and in the method of making the same hereinafter described and particularly defined in the claims at the end of this specification.

In the drawings illustrating .the preferred embodiment of the invention:

.Fig. 1 is a perspective view diagrammatically illustrating apparatus for making .the bufiing elements whichmay be .used .in producing the present bufi'lng wheel;

Fig. 2 is a detail view of .a strand of twisted fiber, .socalled laid sisal, preferably employed in making .the bufiing "element :used in producing the present buffing wheel;

Fig. .2a.is .a similar view showing the preferred .strand partially .untwisted to reveal two component strands thereof; I

.Figs. 3, 4 and .5 are cross-sectional views of the one form of bufiing element embodying the invention illustratingsuccessive stepsinfolding an outer wrapper about the ifibl'OllS strands and stitching the same;

'Figs. :6 and 7 are side elevations respectively of a length of connected buffing elements and of 1a buffing wheel embodying such buffing elements, portion of :Fig. 7 being broken away;

.Fig. 8 is-an edge view, partly cross section, 0f 2a bufiing wheel having a singlerow-o'f 'buffing elements produced in accordance with the present invention;

Fig. 9is assimilar view of a modified form of 'buifin'g wheel embodying two rows ofbufiing-elem'ents to form a duplex bufiing wheel;

Fig. '10 illustrates the rope form of bundle assembly of the plurality of twisted fibrous strands, preferably of so-ca'lled laid construction, which maybe used in produc'ing the present .bufiing elements;

Fig. 1 1 is a .plan view, illustrating more or less diagrammatically, sewing mechanism for producing amodified pattern of stitching in the strip from which .the .present bufiing elements may be formed, as will be..described;

Fig. I2.is a section of aportionof a modified bufiing 'ice wheel wherein the present buffing elements are disposed in U shape and are secured to a hub memberyand Fig. 13 is aplan'view of a portion of the wheel shown in Fig. 12.

In general, the invention contemplates a novel and improved bufiing wheel embodying a plurality of radially extended bufling elements. Preferably, the bufiing element comprises a bundle of or a relatively large number of strands of twisted fibrous material, such as sisal, each strand being of small sectional dimension. The individual twisted strands :may and preferably will comprise a small number of component strands of the twisted fibrous material, and the component strands are twisted to :form :a strand .of the general type heretofore used in the production of stout or relatively heavy sisal twine, and which comprises a construction known in the art as a laid construction. '"Briefly, as is well known in the rope-making art, in producing a .laid construction from two or more strands of twisted fibers, the original twist in each strand is maintained and controlled so as to remain'substantially constant during the operation of laying the component .strands around one another in producing the twine or'pro'duct illustratedrin Fig. 2. Such a 'laid structureis characterized particularly by the absence of any tendency to untwist, and when attempt is made to untwist the laid twine and the .sameis released, the twine :resumes its la'id condition illustrated in Fig. 2. Experience fhas'shown that the laid't-wine or composite strand of :component strands of twisted fibers improves the operationof the present 'bufiing'wheel particularly as to durability and efiiciency.

:In :the manufacture of the individual .bufing elements a plurality of rtwisted fibrous strands, and preferably laid sisal strands, may .be assembled :into bundle forma tion, or :the individual strands may be assembled in a slightly twisted zforrnation'in theiform of a rope, as-shown in Fig. 10. Preferably, 'the :bundle assembly with the individual strands .of .laid or twisted sisal or other laid ortwistedifibrous material, either .assembled in untwisted relation, or the rope assembly with the twisted strands assembled :in slightly :twisted relation, may be enclosed within a wrapping of a :fibrous sheet, preferably cloth, and .the latter stitched or :otherwise secured to form a unitary wrapped assembly. For some purposes a special wrapping of. cloth, paper or-.other sheet may be adhesively secured to and enclose :the bundle assembly. The bufiing wheelmaybe'formed :by a substantial number.of :bufiingelements secured :to a hub member and-extending therefrom Ein .radialmelation and preferably with the adjacent aradial .bufiing elements in closely disposed relation. Conveniently, Ihezinnerends may be stapled or otherwise zsecuredito .alhub provided with an arbor hole for'enablinga series of the-individual bufiing wheels to be assembled on the arbor toform aroll or workable face.

Referring now to .the drawings, as illustrated in Fig. 7 the buffing wheel .in its preferred form may comprise a plurality of radially extended :bufling elements, indicated generally at 10, .connected together at their inner ends, preferably by weaving -Wires.1'2 extending around adjacentbutfing-elements and attached to ahub member for assemblyo'nanarbor'onshaft. Theihub member may take various forms and preferably comprises a metal 'or cardboard supporting ".disk 14 to which the individual buffing elements are secured :by staples .16 to extend radially therefrom as illustrated. Thedisk 14 is provided witha-central opening-18 ,to-fit overtherotary arbonand when composedof relatively thin-.sheet:metal the disk :14

may beprovidecl with a--.relativel y small reinforcing disk 20 :secured thereto about the opening :18 by, staples 22, as shown.

A buffing wheelsthus ,produced forms anfindividual.bufling-wheel section, aplurality of which :may

be mounted side by side on an arbor and clamped together to form a relatively wide buffing wheel or roll.

In accordance with the present invention, each buffingwheel element comprises an assembly or bundle of a relatively large number of strands, each of twisted fibrous material, and with each strand of relatively small sectional dimension. The individual twisted strands may and preferably will comprise a small'nurnber of component strands of the twisted fibrous material, and the component strands are preferably laid to form a strand of the general type heretofore used in the production of stout or relatively heavy sisal twine.

In the preferred form of the invention, the assembly or bundle 24 of the twisted or laid fibrous strands making up the individual buffing elements 10 may be enclosed within an outer wrapper or sheath 26 which may co. prise cloth sheeting or other fibrous sheet material as above set forth. Each buffing element thus formed may be stitched longitudinally, preferably by a plurality of parallel rows of'stitching, indicated at 28, to secure the wrapper about the core and forming a relatively flat, elongated buffing element possessing considerable rigidity and with strands making up the core of the buffing element extended longitudinally thereof. As indicated in Fig. 5, the spaced rows of stitches may pass through both sides of the wrapper and the intervening strands of twine and form in effect retaining compartments maintaining the strands in relatively tightly bundled relation in their separate compartments.

In practice, the bufiing elements 10 may and preferably will be produced by first forming an extended length or strip comprising the bundled strands and preferably the wrapper and by then cutting the same into uniform lengths which may then be connected together at one end in units of one or more bundles by the weaving wires 12 to form a connected length thereof, as shown in Fig. 6. The weaving wires serve to hold the strands in bundled relation and to compress the connected ends of each buffing element and to thus cause the remaining length of each element to flare out to the full width at the free ends thereof. in practice, the extended portions of the elements may overlap somewhat along their longitudinal edges, as illustrated.

In forming a bufling-wheel section, a desired length of connected buffing elements of the form shown in Fig. 6

may be formed into a closed ring of radially extended ele-- ments, the ends of the length being connected by twisting or otherwise securing the ends of the weaving wires together. Thereafter, the closed ring may be secured to a hub member and as herein shown arranged concentrically with respect to the supporting disk 14 and attached thereto by the staples 16; As illustrated in Fig. 7, two concentric rows of staples may be provided, one row within and one row without the circle formed by the weaving wires. The staples are preferably extended through the buffing elements and into the supporting disk 14, the ends of the staples being clinched over the disk as shown, and in practice, the staples in the two rows may be arranged in staggered relation, preferably with the staples in one row secured with both legs thereof extended through an individual bufiing element, andwith the staples in the other row secured with their legs extended through and connecting adjacent bufiing elements. The staggered relationship of the two rows of staples is preferably such that the ends of the staples in one row slightly overlap the ends of the staples in the other row so that all of the underlying strands of twine forming the core of each element are firmly embraced between the legs of at least one staple and secured to the supporting disk, and some of the strands are embraced between the legs of two staples at the points where the staggered staples overlap at their ends whereby to assist in retentionof the strands in assembled relation with the supporting disk during the operation of the buffing wheel.

One form of apparatus which may be used for produc- .through in the manner illustrated in Fig. l.

ing an extended length or strip of the wrapped and bundled assembly of the twisted or laid fibrous strands, such as the sisal twine, is diagrammatically illustrated in Fig. 1, wherein a plurality of twisted or laid fibrous strands, and preferably the laid or twisted sisal strands 24 are withdrawn from a supply thereof, as indicated at 30, and threaded through individual spaced openings in a guide plate 32. The individual strands may then be passed through a spray box 34 to be subjected to a spray of the saturating preparation which may be forced under pressure through a nozzle 36 connected by a flexible hose 38 to a supply thereof, the surplus being returned to the supply through a drain pipe 39 to be recirculated. As illustrated, the strands enter the rear of the box through a relatively wide opening permitting the strands to maintain their spaced relation during the saturating operation. The strands then pass through a relatively smaller opening in the front of the box and over a U-shaped guide member 40 to bunch the strands together. The treated strands then pass through a second guide 42 after which they are arranged to be combined with a web of cloth 44 to provide a sheath or covering for the twisted or laid fiber-core assembly. The cloth preferably previously cut on the bias as indicated may be withdrawn from a supply roll 45 and guided over an idler roll 46 where it is combined with the fiber. The cloth web together with the bundle-strand assembly then pass over a grooved guide member 48 and under a weighted roller 50 arranged to press and flatten the bunch down into the web and into the groove formed in the guide, the groove preferably being tapered and deepened toward its forward end. The marginal edges 51, 53 of the web are then folded over the top of the core assembly in overlapping relation by suitable curved guide rails 52, 54

during the continuous advance of the material there- The composite strip thus formed is then guided through a sewing machine diagrammatically illustrated by the needles 56 to form a plurality of rows of stitches 28 longitudinally of the strip, the strip being advanced by a pair of con tinuously rotated grooved feed rolls 58, 60 as it passes through the sewing machine. The elongated strip of bufling material may then be fed to a weaving machine of known construction, not shown, which operates to sever from the elongated strip successive buffing elements 10 of substantially equal lengths and to connect one or more of the elements together at one end by the wires 12. In the weaving operation, successive sheds are formed on the weaving wires, into each of which the ends of one or more buffing elements 10 are inserted and compressed into compact form and firmly held by the wires to form a length of buffing elements of the form shown in Fig. 6 and as described.

The sisal twine preferably employed in the production of the illustrated bufling elements may and preferably will be of a relatively tightly twisted and laid structure and preferably of the type formed from at least two laid strands of twine 241, 242, see Fig. 2. This structure enables a relatively tight twist to be made and maintained in the twine, as shown in Fig. 2, whereby a durable and highly efficient bufiing element may be produced.

Instead of the above-described mechanism for collecting and bundling a plurality of the twisted or laid strands from a plurality of rolls thereof, a prepared length of bundled twisted or laid strands may be used. Preferably, the requisite number of individual laid twisted strands of the type shown in Fig. 2 may be processedinto general rope form as shown at 243 in Fig. 10, wherein the different strands are slightly twisted, as for example a twist of about in a length of six inches, so as to impart a rope formation to the assembly. The amount of twist may be varied to produce dififerent bufiing effects, and in practice, such a rope may be withdrawn from a reel, not shown, and fed directly through the guide 42 and into the strip-forming mechanism to be provided with the fibrous or cloth covering and stitched longitudinally or cemented, as above described, or otherwise secured to the core.

The slight twist in the rope-like assembly enables straight rows of stitching to pass through all of the strands instead of between them, contributing to the strength of the bufiing elementgproduced.

In a modified form of the invention, the strip of wrapped buff-forming "material may 'be provided with two double rows of wavy lines of stitching extending longitudinally and "from side to side of the strip, one double row of stitching periodically intersecting the other double row of stitching, as illustrated in Fig. 11. This may be accomplished by reciprocating the strip laterally relative to spaced pairs of stitching needles during the continuous advance of the strip through the sewing mechanism. As shown in Fig. 11, the strip of buff-forming material 100 may be fed through a guide member 102 having elongated extensions 104, then into operative relation to the spaced pairs of stitching needles 106, 108, and then between the continuously rotated feed rolls 58, 60, the lower roll 60 only being shown in Fig. 11. The guide member 102 is mounted for lateral reciprocation in a groove 110 formed in the platen of the sewing machine and is arranged to be reciprocated by a cam 112 fast on the feed-roll shaft 114 and through connections including a cam roll 116 carried by an arm 118 pivotally mounted at 120. The arm 118 is connected by a link 122 to one arm 124 of a bell crank pivotally mounted at 126, the second arm 128 of the bell crank being connected by a link 130 to the guide member 102. With this construction it will be seen that as the strip is reciprocated laterally relative to the spaced pairs of stitching needles during the continuous advance of the strip, wavy lines of stitching are formed, the spaced relationship of the two pairs of stitching needles effecting a crisscross pattern as shown.

In order to additionally reinforce and bind together the assembled butting-wheel section, a double row of circular stitching 62 may be provided, the stitching 62 being concentric with and spaced a short distance from the periphery of the circular supporting disk 14, as illustrated.

In the illustrated embodiment of the invention, the butting-wheel sections may be made in single or multipleform types, Fig. 8 illustrating a single-section type, and Fig. 9 illustrating a double-section type. In practice, the single-section type may he produced to provide a greater number of sisal strands in each bufiing element than the bufling elements of the double type. For example, the single type may have approximately 30 to 40 or more strands of sisal twine in each buifing element, whereas the double type may have approximately 20 strands of twine per element.

The single type bufiing-wheel section illustrated in Fig. 8 includes a single ring of buffing elements attached to the disk or hub member 14, as described, the double type section comprising two separate rings placed side by side and stapled together and to the disk 14 by relatively long staples 64, the construction of the double type wheel being otherwise the same as the single type. The separate rings of the double type buffing-wheel section may and preferably will be assembled side by side with the free ends of the buffing elements of one ring in staggered relation to the free ends of the elements of the second ring, as illustrated in Fig. 9, and may likewise be provided with a double row of circular stitching 66 connecting the two sections together at a point a short distance beyond the periphery of the supporting disk 14.

As illustrated in Figs. 12 and 13, the individual butfingwheel elements may be attached to a hub member with the individual elements disposed in U form, and when so doing the strip of covered twisted or laid strand assembly will be severed to produce individual buffing elements of substantially double the length of the bufiing elements shown in Figs. 6 and 7, and such elongated bufiing elements may be assembled in a special hub member, such 6 as is indicated in Figs. 12 and 13 at 140, and such a hub mernber provided with deformable teeth arranged to be bent into the outer surfaces of the two legs of 'the [Ll-shaped buffing element "to secure the same to the hub.

From the description thus far, 'it will be observed that in the bufiing wheel forming thesubject of-the present invention the twisted strand structure contributes to .the efiic'iency and durability of the wheel. It will be observed from a consideration of Fig. 2 that the fibers in the individual strands are indicated as twisted/so that at the wearing surface or peripheral face of the wheel the fibers extend in a non perpendicu'lar relation to the face, or in other words, at an angle somewhat less than a right angle with respect to the face. The effect of this angularity at which the fibers extend at the face of the wheel, as both when the wheel is moved and as it wears down, is similar in its eifect to that produced in conventional prior-type butting wheels wherein the cloth bufiing elements are produced from bias-cut cloth. Experience has shown this angularity plays an important part in enabling the wheel to perform bufiing operations for which prior types of bufling wheel do not appear to be suitable. The exact angularity of the fibers in the twisted strand depends on the amount of twist in the strand and may vary considerably, but as a general rule, satisfactory results have been obtained in which the fibers extend at an angle of from 45 to 60 with respect to the surface of the wheel.

The general type of laid twisted sisal fiber which is preferably employed in the construction of the present buffing wheel is that known in the trade as binders twine and which in fact comprises a stout or heavy twine. The present bufling wheel has been found in practice to impart a superior finish to the work and for some purposes it has been found that by varying the amount of cloth, as for example the number of plies of cloth employed in the bufling element, varied effects may be obtained, such as imparting higher color to the buffed work.

strands, it will be understood that other types of fiber may be used, such for example as jute, hemp, manila and other fibers used in the rope-making art.

Having thus described the invention, what is claimed is:

1. A bufling wheel section having radially extending butfing elements and a hub member to which the buffing elements are secured at their inner ends, said bufling elements being disconnected from one another for a major portion of their length inwardly from the periphery of the bufiing wheel section, whereby to enable the buffing elements to individually flex during a buffing operation, each butting element comprising an assembly of twisted strands of fibrous material extending longitudinally of the buffing element; and a fibrous wrapper enclosing said assembly and having longitudinal stitching extending therethrough and subdividing the assembly into separate groups of strands and compressing said groups transversely and imparting an elongated cross section to said bufiing elements in a direction generally perpendicular to the axis of the bufiing wheel section, the separate groups of strands cooperating with one another to impart rigidity to the individual buffing elements to resist deflection in use, and the wrapper and stitching maintaining said groups of strands in substantially the same relative relation throughout the life of the bufiing elements.

2. A buffing wheel section as defined in claim 1 wherein the twisted strands of fibrous material are sisal and of a cross sectional dimension, such as that employed to produce stout sisal twine.

3. A bufiing wheel section as defined in claim 1 in which the buffing elements are secured to the hub member by a plurality of rows of staples, the staples in one row extending through the individual buffing elements and the staples in the other row being staggered relative While it is preferred to utilize twisted or laid sisal to the first mentioned staples and extending through adjacent buffing elements, the staples in the two rows also including portions overlapping radially, whereby the strands in the buffing elements are securely fastened to the hub member by at least one staple.

4. A buffing wheel section as defined in claim 1 wherein each buifing element comprises an individual assembly of a relatively large number of cords, with each cord consisting of a few but at least two pretwisted yarns with each yarn twisted around the other yarns forming the cord, the twist of the yarns about one another being in a direction opposite to the twist in the yarns themselves whereby the opposed twists balance one another and impart resistance to any tendency of the fibers or yarns to untwist.

' References Cited in the file of this patent UNITED STATES PATENTS

Images