US2576364A - Forced draft buffer - Google Patents

Description

Nov. 27, 1951 M. scHLos's 2,576,364

FORCED DRAFT BUFFER Filed Sept. 26, 1947 2 SHEETS-SHEET l a Vinyl- INVENTOR M02213 SCI/LOSS ATTORNEY NOV. 27, 1951 sc css 7 2,576,364

FORCED DRAFT BUFFER Filed Sept. 26, 1947 2 SHEETS--5HEET 2 1 A. 135- l 1 1D )T :1 4/ T INVENTOR Moe/as SCI/L ass ATTORNEY Patented Nov. 27, 1951 UNITED STATES PATENT OFFICE I FORCED DRAFT BUFFER Morris Schloss, Bronx, N. Y. Application September 26, 1947, Serial No. 776,302

Claims.

' 'The present invention pertains to improvements'in forced draft buffers and methods of making the same. u an object of the invention'is to provide improved rotary buffing means made of fabric in which the structure is such as to permit the passage of ventilating air throughout the entire body of the buffer.

buffer section not subject to undue spreading under pressure.

A further object is to provide a suitablemethod for forming the improved bufier sections of bias cut material whereby the principal threads of all individual fabric layers throughout the section are inclined in the same direction with respect to the direction of rotation.

Another object is to provide improved means of mounting and retaining the buffer sections in multiple.

Another object is to provide hollow cylindrical mounting means of the above nature constructed so as to-permit the free access of the ventilating air to the inner edges of all individual fabric layers in the buffer.

Another object is to provide mounting means of the type mentioned including means to force air from the interior of said hollow cylindrical meansdirectly outward throughout the fabric layers of the buffer.

Other objects and advantages of the invention will appear during the course of the followin description in connection with the accompanying drawings in which:

Figure 1 is a longitudinal section of a typical preferred form of buffer assembly;

Figure 2 is a cross sectional view approximately in the plane 2-2, Figure 1, taken before application of the gripper rings;

Figure 3 is an outer end elevationof an alternative assembly showing a means of regulating the passage of air into the interior; 1

' Figure 3a. is a detail sectional view. of the shutter or regulating means; 7

Figure 4 isan elevation of a preferred form of gripper ring; r

- Figure 5 is an enlarged fragmental' detail view of one of the gripping points taken in the plane Figure 6 is an enlarged sectional view of a portion of the hollow mounting drum or hub showing the lock joint forming a key;

Figure 7' is a fragmental detail section of an alternative form of the drum; Figure 8 is'a diagrammatic side elevation illustrating the first step in the method of forming the improved buffer section;

Figure 9 is a diagrammatic bottom view of the same;

' 'Figure 10' illustrates an optional second step in carrying out the method;

Figures 11-17 inclusive, illustrate successive steps by which-the method is carried to completion;

Figure 18 is an enlarged fragmental view of the inner edge of the completed section;

Figure 19 is an edge elevation of the completed section;

Figure 20 is a side elevation of the same viewed in the direction 2ll2D, Figure 19; and

Figure 21 is a similar view taken in the direction 2i--2I, Figure 19. I

Referring to Figures *1 and 2; the numeral 25 denotes a buffer spindle upon which is mounted a circular rear member 26 having a forwardly directed cylindrical shoulder 21. A hollow cylindrical drum 28 'is fitted at one end on the shoulder' 21. A front member 29, also having a cylindrical shoulder 30, supports the outer end of the drum 28. The member 29 which is retained on the spindle 25 in any suitable manner, preferably by a nut 31, is provided with spokes 32 and is adapted to admit air into the interior of the drum 2B. When in driving position, the members 26 and 29'may be further secured to the spindle 25 by set-screws 6| or the like.

The drum 28 may conveniently be formed of sheet'metal bent into cylindrical form and having alock'joint 33 which performs the double function of holding the drum in shape and also act-' ing as a driving key.

' Thin gripper rings 35, having a plurality of sharp points 36 preferably turned at right angles to the faceof the rings 35 by stamping or the like; are mounted on the drum 28 so that the points 36 grip the sides of the buffer sections 34, pne'ring 35 being provided on each side of each section. v

Key notches 31 in the inner circumference of ringsi35 are adapted to engage the lock joint 33 of the drum 28 in driving relation. Since the innercircumferencesof the bufier sections 54 are resilient as hereinafter set forth, nokey to notohesare ,necessaryin the fabric members to Referring to Figure 8 and the successivemtli- I 0d figures, as previously noted, the buifer section in preferred form may be constructed as follows:

A strip of suitable buffing fabric 39 is cut on the bias so that the principal or grain threads 40 throughout meet SeW'djbihts prqugnt toor we means the successive la'yersiflithecyliiiiirj l a e m re heavilwtxes g tram, the e tleiboutside of the cylinder, rem; purpose'hei'eiriafter g .2 e. .x-lfi,

' e il etd siree aipmb r i a fiei f b in the weave thereof areinclined in one direction 1 .i en

built up on the mandrel 42,3; small sticlier Bor et er s it b atemna a i re ai er appl e I h final tot the wfapa q t e yl ll il aft r. being li YYQQHXQIZPQWY. qf -t aeii of the mandrel 42, may be loosely basted through l ay rsat 5 5, 9 one end9 th y in As the i n sane lural y ree est sate hQlQ a e. punch d. it ri llym hr i b he Cylinder near the end thereof as shown in Figured}; I :Acordjl, Figure 12, 'is then -laced in and out h ou theiholes g .s i cy nd r is next l ced aii 489i an suitable form as illustrated inlii urelfi inwhich the upn portio ofr jig .8 in ud s $9.9m cylindrical, mandrel 74,9 of a, size-corresponding tQ=,:t1f1eldSl1 ed inner diameter'of the completed ufi rsection.

.The'ends 50.51 of, the ,cord ,4! are then-pulled across each.,,fot her 'tighte ning the cord. A1. and rawinajthe ends; of the cylinder, 4. I zzo ly inward in afieriesof uniformconvolutions 52 as shown in Fi ure; 14. K .l When the cord 41 hasbeen tightened tothedesi ed de r wherein the dinner ed espt the, .cony01uti0 s..52 e b a eith cylindri al mandr l. the cylinder 4I'jhas been reformed into, an ,an-

nular fiatishape as. shQwn'inFigure, 16,;jand as the latter shape is substantially thegfi lal iorm gf 'the bnfiingsectiim itlwi'll hereinafter be, referred t r-im u se ti ns. ori i alassi n gn m t n.

Atihi r ai c rd 91 i ciedti iak Due tb the fact 'tnat theedges "of *thefabric layers are not individually gathered, but the assembly of layers is bent into a series of comparatively large convolutions in which the individual layers are mutually supporting, the inner zone of the section is inherently firm and requires no binding rings or means other than the single cord 4'! to hold it in shape during storage, handling and installation on the buffing lathe.

. The original diameter of the cylinder 44 and the fabricfistrrp 39 are so proportioned to the desired final dimensions of the finished section, that the rconvolutions 52, though tightly pressed together their inner zone, taper outward to shallow waivs iir transverse depressions 55 at the outer p eripherv of the section 34 as shown in Figure 19. By this means, the finished section, after having "been pissed-as previously described, comprises an annular ring of uniform thickness with sufficient dnsity throughout its extent to provide ers of fabric rather. than at thev id tire s' e ctlibnjwhi'ch latte 'niaraenge a b sively increased. -Asaresult ofthis increas rig ressu .i ee er a were. t fi i e essi e cmp e than ihe vnrlei t jw e th nderis armed nfia fl gel a wash he additi al ea as iiene i 29. l r I .QO Sf l f. Qr,.. i r sli ht inc a e i f ference of er ueee siveow an s s.t e on he wa bu lt. tB th sm an i e fina pnier i none: m la e si the se t n sgre i g uniform throughout. Since the section rmedias QE Q li'bQQZPYJ rewi es a n the. winde s Lill n iai s ntp e1 i v .l !e layers, ofthe fi s ed sec ion- 4 is thesa e vvIlhis eliminates gorim nim ze the necessi Zion :fiae peripheral trimming of the sectionin ,o rder to Secure a ,;uniform ;cyl indrica l outer surface, "an obvious advantage" and saving of material -over former imetho'ds; in which 1 a section, has been formed by gather ngfercrimp ocy n er inward around its middle zon e, ;[n ,the ;case of as'ection formedby the" latter method; the initial profile of the outer circumferenee' isnecessarily 'convex,."requiring 'considerablatrimming and waste of material to render it cylindrical, A

r A further advantage achieved by the method of drawing in one end "of 'the "cylinder-is that inal1'layers of the finishedsection, the principal V threadszorwarp of the fabric" layers-rarednclined in one direction from;the"radia l 'dire'ctionf-as illustrated 'in'" Figures 20, 21, which figures 1 representviews of -'opposite' endsof the same section 34, Figure 19. r

In operation inl'the direction? indicated by "the arrows in Figures 20, 2 l,it"will'be""seen that the principal "threads 60 slop'e backward with respect to the direction of rotation and wit'h'respect to "any-object such as; 51 thrust against the jsection 34 for bufimg. similarlmyif thebufferf is revolved in the other direction, alhprincipal threads are inclined forward against the work in the direction of rotation, It has been determined ,by experience that when the warp or principal threads are uniformly inclined as noted, the uniformity of work and the quality of work are much superior to those of buffers in which all or part of the principal threads are sloped at various angles with respect to the direction of rotation. This is due to the fact that forwardly inclined threads produce a different type of effect on the work than those inclined rearwardly. Thus a section made as described herein may be used for either desired type of work, for example roughing or polishing, simply by arranging it to revolve with the principal threads inclined in the chosen direction, and with uniformly high quality of either type of work.

The above described quality of uniformly sloping principal threads throughout the section is one of the principal advantages of the described present method of forming sections, as it will be obvious that in sections made by the former method of crimping a fabric cylinder inward in its middle zone, the principal threads of half the finished section will be sloped rearwardly and the other half forward, resulting in uneven wear and irregular or inferior buffing, Furthermore, the buffer section formed by the present method as described, without middle crimping of the fabric cylinder, eliminates the tendency for individual sections to spread apart in the middle under bufling pressure.

The general operation of the device is as follows:

The desired number of buffer sections 34 is stacked on the drum 28 with gripper rings 35 between their inner rims as shown in Figure 1.

A pressure ring 58 is then placed on the outer end of the drum 28 and the member 29 is drawn tightly inward to clamp the assembly together by means of the nut 31 and the setscrews 6| are tightened. As the buliing assembly is revolved at high speed to perform its function, louvre blades 38a force a blast of air from the interior of the drum 28 directly out through the openings 38 and through the previously described interstices 56 throughout the entire extent of the bulfing assembly. By this means air is forced under pressure among and between all individual'fabric layers of the buffer assembly, the outward passage of air not being limited to zones between sections as in the case of buffers in which the sections are internally bound by metal or other imperforate rings, or where the sections are mounted on solid guiding surfaces. Absence of intermediate supporting discs or the like in the interior of the drum 2B permits unobstructed passage of air to the louvres 38 and thence to the exposed inner edges of the fabric layers. The sirocco fan effect of the louvre blades 38a gives comparatively high direct air pressure which assures circulation through the smallest passages, thus allowing the use of a buffer of high density and firmness, as previously noted, while maintaining ample ventilation throughout the buffer.

For some types of buffing it may be desired to modulate the powerful pressure effect of the sirocco or centrifugal fan drums. For this purpose means may be provided to throttle the intake of air to the interior of the assembly, as illustrated in Figures 3 and 3a, in which a pair of apertured plates 62 and B3 are clamped on the spindle 25 between the member 29 and the nut 3!. The plates 62 and 63 may be rotarily adjusted with respect to each other as a shutter to provide a variable common orifice 63a giving any desired throttling effect on the incoming air.

If desired, the fan-drum may be constructed in alternative form as illustrated in Figure 7 in which a large number of small tabs 59 are struck inward at an angle with the main drum cylinder 28a so as to underlie perforations 60. When such a drum is revolved in the direction indicated by the arrow, Figure 7, the tabs 59 scoop the air outward through the perforations 60, also after the manner of a sirocco fan as previously set forth.

In practice, various lengths of drums 28 may be provided to allow the building up of buffer assemblies of any desired length. As all the blades of the fan drum are on the inside of the drum, they are not a source of danger to the operator as in the case of exterior fans.

While the invention has been described in preferred form, it is not limited to the exact embodiments illustrated, as various modifications and changes may be made without departing from the scope of the appended claims.

What is claimed is: e

1. In a device of the character described, in combination, a rotary spindle, a hollow drum of greater diameter than said spindle, means to support said drum concentrically on said spindle whereby a chamber is formed within said drum about said spindle, said drum having louvres forming openings through the periphery thereof to said chamber, an annular buffer comprising a plurality of fabric layers supported on said drum and having interstices between individual layersforming radial passages throughout said buffer, the inner edges of said individual fabric layers being in engagement with said drum whereby said interstices are disposed in communication with said louvres, said louvres having inclined blades adapted to force air from said chamber out under pressure through said louvres and said radial passages.

2. That method of forming a rotary buffer section which includes the steps of winding an unfolded strip of bias-cut fabric spirally in successive layers to form a hollow fabric cylinder, punching a ring of equally spaced holes radially through said cylinder in a zone adjacent one end thereof, lacing a cord alternately inward and outward through successively adjacent holes throughout said ring, retractin the protruding ends of said cord to draw said end of said cylinder inward in a series of uniform convolutions whereby said cylinder is converted into a substantially flat annulus of predetermined inner diameter, and securing the ends of said cord.

3. A method as described in claim 2 in which the winding tension of said strip is progressively increased as said cylinder is. built up in said successive layers.

4. A method as claimed in claim 2, including the step of axially compressing said substantially flat annular section while radially supporting said section throughout the inner circumference thereof.

5. A device as claimed in claim 1 wherein said drum is formed of sheet metal bent in cylindrical form and joined in an outwardly extending lapped seam, wherein said buffer is built up of a plurality of sections each comprisin a plurality of said individual fabric layers, and including means between said sections to grip the inner zones of said sections, said gripping means having MORRIS SCHLOSS.

REFERENCES CITED The following references are of record insthe file Of this atent:

Number UNITED STATES PATENTS Name Date Keighley 1 Apr. 16, 1895 Number 8 Name Date 7 Myers -a-- Yohe 1- -1 June 11, 1935 Zimmerman 1 July 13, 1937 Hall Oct. 5, 1937 Kreilick-et a1 -1 Jan. 25, 1938 Zimmerman Mar. 8, 1938 Kreilick et a1. Sept. 20, 1938 Levoy Nov. 15, 1938 Murray Dec. 13, 1938 McFarland etal. -19. Dec. 31, 1940

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