Патент USA US2404864код для вставки
July 30, 1946. A. ‘SANDOW ET Al. 7 Y 2,404,854 METHOD OF MAKING, PACKING RINGS Filed Feb. 11, 1945 INVENTORS .S?/VDOW . ,9. WEA/ZEL . ATTORNEY Patented July so, 1946 2,404,864 UNITED STATES. PATENT OFFICE 2,404,864 METHOD OF MAKING PACKING RINGS Abraham Sandow, Plain?eld, and Albert A.‘ Wenzel, West Orange, N. J. Application February 11, 1943, Serial No. 475,504 3 Claims. (01. 29-15626) ‘ 2 This invention relates to a method of making packing rings, and more particularly to rings which have an inherent resiliency tending to con tract the same. _ Generally speaking, it has been common prac tice to construct and use packing rings which have an inherent resiliency tending to expand the rings. When such rings are used in internal combustion engines, for instance, it is necessary ‘ 7 Still further objects will appear as the de scription progresses, both by direct recitation thereof and by implication from the’ context. Referring to the accompanying drawing show ing one embodiment of the method and one form of butt-end split ring, and in which drawing like numerals of reference indicate similar parts throughout the‘several views; . i, , . Figure 1 is a perspectiverview of a completed to mount them in grooves in the piston so they 10 contracting ring in accordance with the present will expand into contact with the cylinder wall. That in turn necessitates a wall‘thickriess for the piston which permits cutting the groove therein and still leave a suflicient amount of metal at the base ofthe groove to afford requisite 15 invention; ‘ . . . Figure 2 is a perspective view of a cast pot or other tube constituting‘the stock forring pat terns; , v v Figure 3 is a perspective view of a pattern blank strength to the piston. The greater part of the as out from the stock; . Figure 4 is a perspective view of the pattern piston therefore has considerable more thickness than is required. from the standpoint of strength, blank being severed to give it the form of a split ring; ' l ‘ and the extra thickness means additional weight, to which must be added the weight of the rings, 20 , Figure 5 is a perspective view of the split pat in calculation of inertia developed in the re ‘tern blank with one end sprung to overlap the ciprocal movement of the piston. This inertia may be very materially reduced by the expedient Figure 6 is an edge view looking toward the of providing a thin and smooth-wall piston, and overlapped ends and showing the pattern com situate the rings in the wall of the cylinder in if 25 pleted by ?llet material; . , . ‘ . ' Figure '7 is a plan of a pattern board with sev appropriate grooves. That necessitates, however, eral of ‘the pattern rings thereon and gated to that the rings‘must have an inherent contract ing resiliency and be perfect circles in the con gether with a common sprue; . " ‘ tracted position. While some attempts have been Figure 8 isa perspective view of one of the cast , made to construct contracting rings, di?iculties to rings‘ have been encountered in casting, tensioning Figure 9 is an edge view of the casting in proc ess of having longitudinal cut made at the over and shaping the same, and these di?iculties, un lap region; . , til now, have prevented adoption of contracting rings for use in internal combustion engines. Figure 10 is an edge View showing excess end In the broadest aspects of the invention,_there Li metal being out from the casting; and other; fore, an object thereof is to overcome the dii? culties of manufacture encountered in construc tion of a contracting ring. Another object of the invention is to obtain a ‘method of making a contracting ring which will have perfect shape of a circle at piston diameter but a further tendency to contract when at piston diameter‘ ‘ ‘ ‘ Yet another object of the invention is to avoid operations which would disturb or change the given circular shape of the ring. ' A further object of the invention is to adapt the manufacturing process to correspond as near possible to present-day manufacture of ex panding rings. H ‘ ‘ . i i T Figure 11 is a sectional view of a portion of a piston and of a cylinder, and showing rings in sectional cross section mounted in grooves in the cylinder and in engagement with the piston which slides within the “rings and cylinder. In the speci?c‘ embodiment of the invention illustrated in said drawing, and referring initially to the method involved, reference numeral 15 designates a pot or other tube constituting one means from which pattern blanks l6 are to be formed. The‘ pattern blanks 'are severed as rings from the pot I5, indication being given by dotted line I‘! where one pattern blank is to be out off therefrom. Pot I5 is a true cylinder, hav ing outside and inside diameters equal, by a pat tern-maker’s rule, to the dimensions which it is desired that the packing, ring shall have. In severing the blank from the pot. the blank is ‘Again, an object of the invention is to require a minimum of ?nishing operations. Yet again, an object‘ of the invention is to em ploy ?nishing operations which are of simple given a thickness between flat faces, also by a character and readily performed. pattern-maker’s rule, either directly when out ' 2,404,864 3 ting or by subsequent grinding, equal to the de sired thickness of the packing ring casting to faces ground and then appears in ?nal form as ring 21 of Figs. 1 and 11 tensioned to contract with its ends 26' abutting. be made from the pattern. Of course over-size allowance may be made for any surfaces corre sponding to surfaces of the ?nal ring which are to be ground to size. - One use of rings as thus manufactured is to situate the same in grooves 28 cut circumferen tialiy in a cylinder wall 29 of an internal combus - tion engine, and with the inner periphery of the After the pattern blank I6 is severed from‘ ring 27 in sliding engagement with and consti the pct 15, said blank is transversely cut, as by tuting a sealing surface with a piston 30. Thus a saw l8 as ‘shown in Figure 4. The pattern blank is then of size and shape desired for the 10 the piston is the only moving part and may be ?nished ring to be cast, and has normally abut-v thin-walled, smooth-faced or devoid of grooves and not required to carry the additional weight ting ends, butwdevoid of the tension desired in of the piston rings, thereby reducing inertia to the ?nished ring. One of the end portions of the pattern ring or blank is now sprung or bent , a minimum. upward from the bottom plane of the ring. The upwardly bent portion may be and is thereupon fact that the'ring or rings will be located far ther away from the combustion heat and gases. While this use is illustrative of a bene?cial pur pose involved in the invention, other uses may be made of rings constructed in accordance with the compressed or slid longitudinally of itself over and longitudinally of the other end portion and: held compressed with the said end portions over lapping, (see Fig. 5). The next operation is to ?ll the region beneath the sprung end portion of the ring, as by ?llet material l9, as shown done in Figure 6. present disclosure. Furthermore, variations may be made in the performance of the several oper This operation restores a ‘ level bottom to the pattern and also ?lls the gap between the overlapping end portions. Atten- tion may be directed to the fact that ample thick ness of ?llet material is placed between the over lapping end portions to allow for a casting thickness thereat to accommodate a saw-cut or slit when completing the ring from the casting. Addition of this ?llet material completes the pattern. Afurther advantage of this exam- ‘ .ple of use of our improved'ring resides in the ations and steps explained above for accomplish ment of the construction, purposes and results ‘ desired, it being understood that the arbitrarily selected showing of apparatus and procedure shown in the drawing and discussed in thespecil ?cation ‘is for illustration of the inventive con cent of which the drawing andv description must of necessity give one speci?c example. ‘ We claim: 1. A method of manufacturing cast packing rings with inherent contracting tension com A plurality ‘of patterns, with ?at face down, arev appliedto a pattern board 2!] to which they prising forming a pattern the size and shape of ‘may be pinned or otherwise secured inv accord the desired ring, cutting said pattern and over ance with usual practice. Gate patterns 2.! con lapping the ends' thereof, making a casting ‘cor nect from the several ring patterns, preferably at responding to said pattern, slitting the casting in the overlapped end portions of each, to a com conformity with the overlapping‘ of the pattern, mon sprue pattern 22. Usual foundry practice and spreading and ?attening the ring with the is followed in forming sand or other mold with 40 ends thereof abutting. the patterns and casting the several rings, of . ,2. A metnod'of manufacturing cast packing which Figure 8 shows a cast ring as it comes rings with inherent contracting tension compris from the foundry. ing forming a pattern the size and shape of the The next operations on the casting are to cut . 45 desired ring, cutting said pattern and overlap the overlap and remove excess metal. As indi ping the ends thereof, making a casting'corre cated .in Figure 9, a saw 23 may be used. to cut, spending to said pattern, slitting and cutting the at ring thickness from sloping face‘ of the cast casting to provide overlapping ends in conforme ing, one overlapped end portion from the other, ity with the overlapping of the ends of. the. pat making a slit 24 through the ring as shown in 50 tern, and spreading and?attening the ring with Figure .10 longitudinal of the sloping end portion said ends thereof abutting and pressed endwise together. . giving proper thickness thereto. Then, as illus trated by Figure 10, a saw 25 is employed to cut 3. A method of manufacturing cast packing 7 the excess tapering material 26 from the under rings with inherent contracting tension compris-v end of the ring beneath slit 24 after which the 55 ing forming a pattern ring the size and shape ring conforms with and has appearance of the of the'desired ring but without the inherent con pattern of Figure 5 with overlapping ends, ex tracting tension from desired ring size, cutting cept that said ring now tends to spring to over said pattern ring and forcibly overlapping the lapped position of end portions. The sloping or ends and contracting the pattern ring and secur upwardly bent end portion is next forcibly spread ing the overlapped margins together whereby lengthwise from the end portion which was cast 60 the pattern ring is constituted a contracted. pat to slope upward and its end forced into abutting tern of smaller circumference than the desired relation to the other end. Thereafter the metal packing ring, making a casting corresponding to is treatedappropriatel'y ‘to give that end which the said ‘contracted pattern, ‘slitting the casting was cast on the slope a normal tendency to re in conformity with the overlapping of the pat ‘flat with the rest of the ring. .The treat ment is such .as not to disturb the circular con tern,‘ and spreading the ring the amount of over lapping of the ends until the ends register and dition of the ring .nor the tension in vthe ring to the ring expanded against the inherent tension press the ends into abutting relation. Such of the casting and its ends brought into abut treatment may be a forcible bending applied to ment with each other and pressed endwise to 70 the metal, by peening, by heat, by a combina gether under the inherent tension of the ring. tion of these treatments or otherwise as. found ABRAHAM SANDOW. desirable. The ring may ?nally have its ?at ALBERT A. WENZEL.