Letters Patent of the United States is:- 1. In an internal combustion engine, comprising a piston having an upp ' er ring section and a 65 lower section connected thereto by internal ribs and providing an annular slot between the seetions, the lower section having an invVarcUY and upwardly extending flange adapted t-o catch oil splashed up into the piston for passage outwardly through said slot, said piston also having b6low the annular slot ai@d in its peripheral surface a plurality of grooves communicating with said slot for the reception of lubricant therefrom. 2. In an internal combustion engine, a piston 75 having an uppet ring section, and a spaced lower sectioii connected thereto by intemal ribs and providing an annular groove between the sections for free passage of lubricant into and out of the piston, said lower section having an annular oil groove spaced below said first groove, and pro- 80 vided at one side with a vertically disposed receiving groove communicating with the second oil groove, and adapted to receive oil from a source of supply for distribution to the second oil groove, said piston also having in its outer surface and 85 in its lower section a plurality of cross grooves intersecting and communicating wit@ both of said grooves and said annular slot. 3. In an in.ternal combustion engine, a piston having an upper ring section and a lower lubri- 90 cating section connected thereto by ribs and with an annular slot between the sections, said lubricating section having peripheral cross grooves therein opening at their upper ends into said slot, said lubricant section also having an an- 95 nular oil groove interm6d!ate its ends, and intersecting the cross grooves, and further provided with a supply groove in one side intersecting the cro--s grooves, and Said anriular oil groove. 4. in an internal combustion engine, a piston 100 having an upper ring section and a lower lubricating section, with the sections connected by integral internal ribs and providing an annular slot between the sections, said lower section having wrist pin trunnions with flat outer ends open- 105 ing into said slot, said lower section also having an annwar oil groove opening into said trunnions at the bottoms of the flat ends thereof, and provided *ith intermediate grooves opening into said slot and annular groove, and through the 110 lower end of the lower section. 5. A piston comprising an upper ring section provided with a series of ring grooves therein and with openings leading through the wall of a lower ring groove to the interior of the piston, said 115, piston having an annular groove at the bottom of said ring section, and provided with openings leading from said groove to the inte'rior of the piston, said piston also having a second annular groove spaced below said first groove and with 120 openings through the upper wall of said second groove leading to the interior of the piston, and provided in line with the bottom of said second groove and the opening leading therefrom with an upwardly and inwardly inclined oil entrapping 125 flange for catching and directing oil through the openings into said second groove. 6. A niston comprising a ring section, a lower section beneath the ring section, an annular oil groove at the inner end of the ring section having t3O a lower Inclined wall with openings therethrough leading to the interior of the piston, said lower section having an intermediate annular oil groove spaced below said first groove and provided with a longitudinal oil receiving groove in its side. opening Into said second annular groove adapted to receive lubrlcant under pressure for supplying lubricant to said Second annular groove, said lower section of the piston also having exterior intermediate grooves intersecting both of said oil grooves for distributinf oil under pressure entirely about and throughout the length of said lower section. 7. A piston for an internal combustion engine, comprising a body portion having upper and lower sections with a circumferential slot between the sections, said body portion aiso having an inwardly and upwar ' dly extending flange at the lower wall of the circumferential slot for catching oil splashed up into the piston and directing jC.

the oil outwardly to the outer surface of the piston, the lower portion of said body part of the piston having in its periphery a plurality of crossed grooves. communicating at their @upper ends with the circumferential slot at the outer portion of said flange for receiving the oil therefrom for distribution over the exterior surface of the lower portion of the piston. 10 20 25 30 35 40 45 50 55 8. A piston including a skirt having iij its outer surfwe a substantiany eireiir@erentiary continuous, sinuous oil groove including portions diagonally-laterauy inclined and terminal portions extending beyond - adjacent intersecting groove 80 portions. ALEXAMER M. ALEXAMRESCU. 85

Patented Mar. 20, 1934 UNITED S'TATES PATENT OFFICE 1,951,959 PISTON AND RING CONSTRUC'EZON Alexander-M. Alexandrescu, Cleveland, OWo ALoplication May 23,1930, Serial No. 455,036 8 Claims. (Cl. 74--108) The present invention relates to piston and ring con,@,truction and has for an object to provide an improved construction of piston and an improved congtruction and arrangement of rings for cooperating therewith for effectively sealing the piston when used in iliternal combustion engines to maintain proper combu@otion in the cylinders, a@nd to prevent seepage of oil past the pi@.ton from the crank case. 10 Another object of the pres6nt invention is to provide an improved construction of pigton for catching and distributing the lubricant between the piston and its cylinder wall, and to provide 15 a piston, which readily adapts itself to conditions within a cylinder when the piston is unduly expanded by heat. Another object of the present invention is to provide a novel arrangement of piston ring and a cooperating expander for use tlierewith, and 20 with novel means for carrying the lubricant behind the rings and to the interior of the piston. A further object of the invention is to provide a cooperating con@@ti-uction of i3iston ring groove and combined ring structure, whereby the ring 25 may automatically take up inaccuracies of width of groove occasioned in either manufacture or in-cident to wear, and which, cooperating with piston lubricating construction, will maintain the piston, after wear, tightly and from vibrating 30 and knocking in the cylinder. With the foregoing and other objects in vie)w, the invention will be more fully described hereinafter, and will be'more particularly pc)inted out in the claims appen@ded hereto. . 35 In the drav6ngb, wherein like symbols refer to like or corresponding parts throughout the @.everal views. Figure I is a fragmentary vertical section taken through an iiltornal combustion engine showing 40 a piston and ring constructed according to the present invention mounted therein, the dotted lines showin.- the lowermo--,t pc,.@;ition of the piston. Figure 2 is a fragmentary section taken through the same axially at right angles on the line 2-2 of Figiire 1. Figure 3 is a fragmentary vertical section similar to Figure 1, but ,,hbwing the piston in @@ide elevation. 50 Figure 4 is a view similar to Mgure 2, but ,.iowing the piitoii in side elevation. Figure 5 is a reduced transverse sectioii taken on the line 5-5 of Mgure 3. Fligure 6 is a s-imilar view, but taken on the 55 line 6-6 of Figure 4. Figure 7 is a fragmentary sectional view similar to Figure 4, but showing a modified construction of piston partly in section, and showing a force feed lubricating means therefor. Figure 8 is ii sin-jilar view, bilt taken axially 60 at right angles on the line 8-8 of T-Pigure 7. Figure 9 is a transverse section taken through the modified form substantially on the line 9-9 of Figure 8. Figure 10 is a like view taken on the line 10-10 65 of Figure 7. Figure 11 is a fragmentary vertical section taken through a cylinder with a piston therein, partly in section, and showi-Tig another modifica- 76 tion in the construction. Figure 12 is a transverse section taken on the line 12-12 through Figure r,igure 13 is a longitudinal section taken through a locomotive cylinder and piston mounted therein, sh'ow'mg the mounting of the 75 piston rings therein. Vigure 14 is a transverse section ta-kep- through the same substantially on the line 14-14 of Figure 13. Figure 15 is a vertical fragmentary section 80 taken through the cylinder of an intemal combusfion engine, showing partly in elevation and partly in section another modified form of the piston. Figure 16 is a transverse section taken through @5 the same substantially on the line 16-16 of Figure 15. Figure 17 is a like view, but taken on the line 17-17 of Figure 15. Figure 18 is a fragmentary vertical section 90 taken through a cylinder of an airplane motor, or compressor showing a further modiflcation of piston, and means of forced lubrication therefor. Figure 19 is a transverse section takeii through 95 the sarne on the line 19-19 of Figure 18. Figure 20 is a similar view taken on the line 20-20 of Figure 18. Figure 21 is a fragmentary enlarged horizon. tal section taken from Figure 16, and showing the 100 ring and spreader arrangement 'in the ring groove of the piston. Figure 22 is a transverse section taken through the same on the line 22-22 of Mgure 21. Figure 23 is a detail fragmentary view looking 105 at the inner.side of the ring spreader section showing the oil or pressure slots in the upw; and lower edges thereof. Figure 24 is a detail fragmentary sectioiial view of a portion of the piston, showing the ring lio

grgove therein, and iuustmting diagrammatiCaUy the various angular positions of the opposite wars thereof. Figure 25 is a plan view of the ring spreader employed. Mgure 26 is a similar view of a slightly modifled form of the spreader. Figure 27 is a fragmentary outer side elevation of a portion of the ring spreader shown in Fig10 ure 25. Figure 28 is a transverse section through the same taken on the line 28-28 of Figure 25. . Referring to the drawings, and first to Figure 1, 30 designates the cylinder of an intemal com15 bustion engine of any suitable type, which is provided with a head 31, suitably mounted thereon, and forniing therewith a compression chamber 32. The cylinder 30 is provided at one side with a valve spring case 33, in which is disposed the 20 springs 34 and tappets 35, the case 33 having a closure plate 36 sealed against its outer side for maintaining therein a bath of oil 37. The side of the cylinder 30 is provided with an oil passage 38, which leads from the lower end 25 portion of the valve spring case 33 for conducting oil from the oil bath to the interior of the cylinder, and against the piston located therein. The improved piston disclosed in Figure I comprises a hollow cylindrical body part 39, hav30 ing at its upper portion peripheral ring grooves 40, which are relatively wide and adapted to receive composite piston rings composed of spaced annular sections 41 urged apart by intermediate wedge sections 42. The opposite walls 35 of each piston groove 40 flare outwardly, and the spaced sections 41 of the ring have their outer surfaces correspondingly bevelled or inclined to bear against the sides of the ring groove 40, and have their inner opposite faces bevelled or in40 clined to slidably receive thereagainst the opposite inclined faces of the wedge sections 42. The piston 39 is provided at its interior with longitudinally extending webs or reinforcements 43, which taper downwardly toward the lower 45 portion of the piston, and adjacent to the depending skirt 44. The piston 39 is provided immediately. below the ring section thereof, with an inwardly and upwardly inclined oil collecting flange 45 of suitable depth, and disposed at a 5( suitable angle for collecting oil, and deflecting the oil through one or more peripheral slots to the piston. The oil grooves or passages, being located immediately below the ring section, serve as vents for ofl accumulating beneath the rings, so that the oil may escape inwardly over the collecting flange 45. Thus the flange 45 and the slots 46 serve to relieve excess accumulation of oil, and also serve to supply oil mthen such is lacking. The intermediate portion of the piston 39 is provided with a plurality of cross grooves 47, which are cut into the peripheral surface of the piston, and extend substantially spirally thereabout, and intersect one another at desired points, 65 the free ends of the cross grooves 47 opening into the slots or passages 46, so as to receive oil accumulating therein, and spread the oil uniformly over the peripheral surface of the piston. The intermediate portion of the piston carries i'D the usual trunnions 48 in which are mounted bushings 49 for supporting the usual wrist pin 50. The piston is provided in opposite sides, in registn, with the outer ends of the trunnions 48, with flat faces provided with vertical grooves 51, which 7,3 open at their upper ends into the slots 46 to receive the 6il therefrom, and which also ol3on into the cross grgoves 47 for insuring the rapid spread of the oil over the otiter surface of the piston. The trunnioiis 48 are provided with oil passages 52 therein, which lead inwardly and downwardly 80 from the point of mergence between. the circumferential slots 46 and the vertical slots 51, as shown in Figure 2. The piston is ajso provided at its outer waU with a longitudinally extending oil slot 53 whirh 85 is spaced between the slots 51 and adapted to register at times with the oil passage 38, which leads from the oil bath in the valve spring case 33 for supplying a quantity of 'oil to the groove 53 each time the piston moves inwardly towaxd 90 the end of its stroke. This oil groove 53 opens at its lower end into an annular oil groove 54, wliich extends entirely around the piston, and which intersects the intermediate portion of the cross grooves 47 for supplying a charge of oil 95 to the upper and lower portions of said cross grooves 47. The lower portions of the grooves 47 extend through the skirt 44 of the piston and open through the lower edge thereof, the said edge of the skirt 44 being preferably turned in- 100 wardly as shown. The webs or reinforcements 43, which axe arranged longitudinally within the upper part of the piston 39, provide the sole connection between the parts of the piston 39, which axe located above 1@',3 and below the circumferential passages or slots 46. In the modification shown in Figure 7, the wrist pin 55 opens directly into the end slots 51, and the cylinder 56 is provided opposite one of tlle grooves 51, when the piston is in its lower- 1'-) most position with an oil supply conduit 57 adapted to deliver oil undek pressure directly into the hollow wrist pin 55, and also into the oil groove @l. It is apparent that duringthe movement of the piston past the oil conduit 57 that oil will be l@.3 discharged into the slots 51 throughout the,length thereof, so that the oil under pressure will be properly distributed into the various grooves and passages of the exterior surface of the piston, as weU as into the wrist pin 55. The wrist pin 55 I'@ 3 is provided with the usual oil openings 58, which conduct the oil to the surface thereof. The lower part of the piston is provided- with a plur,,aity of longitudinally disposed expansion slots 59, which open tirough the outer peripheral l@' 5 surface of the piston, and wwch extend inwaxdly by virtue of interior U-shaped ribs 60, dividing the outer surface of the piston into a plurality of segments adapted for expansion and contraction toward and from one another. i'al) Referring now ' to the construction shown in Mgures 11 and 12, it wiR be noted that the piston is divided into three sections, an upper ring section 61, an intermdiate piston section 62, and a lower skirt section 63, these parts being interconimuni- l@3 eating and held together by longitudinal -webs or ribs 64, which extend throughout substantially the entire length of the piston. It will be noted that the ring section 61 and the intermediate seetion 62 are slightly spaced apart, as before de- 14,) scribed, to provide the annular recesses or slots 46, and like circumferential slots or grooves 65 are provided between the intermediate @ection 62 and the lower skirt section 63. It will be noted that these slots 65 intersect the cross grooves 47, and that the lower slots 65 are provided at their lower edges with a collector flange or lip 66, similar to ihe lip or flange 45 her6tofore described. Referring now to Mgures 13 and 14, 67 designates a cylinder of a steam engine or the like, 150

such as a locomotive, and has therein a piston'68 provided with relatively ,Wide ring grooves 69, having spaced ring sections 70 and 71, the outer surfaces of which conform to the opposed wars of 5 the ring groove, so as to seat flat thereagainst to seal the ring in the groove. The inner edges of the ring sections 70 and 71 are inclined outwardly toward each other to receive therebetween an annular *edge section 72, normally urged by its 10 inherent resiliency between the sections 70 and 71 to at all times maintain the same in spread and outwardly urged position. The wedge section 72 of the ring may be provided with oil or compression passages 73 leading through the section 72 15 to equalize pressure a the opposite faces thereof. In Figures 15, 16 and 17, there is shown a construction which is preferable in use in large bore mo'Llors, although it may be used in small bore motors. The structure is adapted for use only 20 with the splash system of lubrication. In this form, the upper part of the piston 74 is provided with the ring grooves 75 provided with composite piston rings therein, as above described, and which have wedge sections 76 with grooves or re25 cesses 77 in the up-uer and lower faces thereof, leading from the outer to the inner sides of the wedge section 76 for equalizing pressure at its opposit6 sides and for admitting the passage of Oil or co,.npression behind the rings. The lower ring 30 groove 75 is vented to the interior of the piston 74 by a plurality of openings 78, which lead through the inner wall of the piston, so that accumulation of oil and pressure behind the lower ring may be vented to the interior of the piston. 33 Immediately below the ring section of the piston 74 the latter is provided with an exterior annular oil groove 79, the lower wall of which is inclined outwardly and downwardlk, and provided with a plurelity of openings or perforations 4.0 80, which extend through the viall of the pisto@-I and relieve pressure and oil accumulation in the groove 79 to the interior of the piston. The lower portion of the piston 74 is provided with a second anrular oil groove 81, the lower wall 45 of which forms substantially a continuatio,-i of an upwardly and inwardly directed oil catching flange 82, which extends inwardly beyond the inner wall of the piston and provides a pocket at the upper side of the flange 82 for entrapping a .,3 quantity of the oil splashed up into the piston. The upper wall of the .-roove 81 is provided with a desired number of oil passages 83, which open into the bottom of said pocket, so that the oil entrapped above the flange 82 may flow down into @3 the groove 81, encircle the piston, and flow upwardly and downwardly through the cross grooves 47. If desired,,@ing spreaders may be employed, such as shown in Mgures 15 and 16, and which are co disclosed as being disposed behind the two lower piston rings. These spreaders may be constructedasshowninFigures25,27and28. Thespreader comprises an anniilar split band 84 of resilient material with an inherent tendency to spread, cj and which is relatively narrow and adapted to seat behind the wedge section 76 of the rina. -At spaced intervals throughout the len@th of the band 84 are secured thereto by welding, riveting or other suitable means, a plurality of 70 spring tongues 85, the same extending from the outer side of the band 84, and having transverse-. ly enlarged heel portions 86 of greater width than the band 84, and adapted to bear against the lower and upper walls of the ring groove 75 to maintain the spreader against vertical shifting in 3 the ring groove, and in correct alignme nt with the wedge section 76 of the ring. The se @prilarged heel portions 86 also serve the purpose of providing arnple. clearance beneath 00 the lower edge of the band 84 for free passage ot - compres sion and oil from behind the ring through the openings 78 in the wall of the piston 74. Figu re 26 shows a slight modifteation in the construc tion of the spreader having the band 84, which carries a plurality of st)ring tongue's 87, 85 which extend on the band in a direction opposite to the direction in which the spring tongues 85 extend upon the band 84. Otherwise the construction is similax to'the showing in Figure 25. Ref erring now to Figures 18, 19, and 20, there 90 is shown a cylinder 88 adapted for use particularly in airplane motors, compressors for very high compression, and the like, and which is provided with a piston 89. The piston 89.is provided with the ring grooves 75 with the rings as 95 hereinbe fore described, and eael-i comprise the spaced sections 41 and the expanding sections 76, with the walls of the ring grooves substantially in pararel relation, and the pistgn 89 is also provided near its top with a relatively small ring 100 groove 90 of usual dimensions, and construction, *hich is fitted with the usual type of ring 91. This particular construction is resorted to for insuring a more ea,-zy operation of the rings when subjected to relatively high temperatures. 105 The lower ring groo've 75 is vented to the interior of the piston 89 by the operiings 78 hereinbefore describe d, and the piston -is also provided with the annular groove 79 having the openings 80 through its lower wall, which vent the groove 79 110 to the interior of the piston. 89. The section of the pigton 89 b--low @'he groove 79 is provided with the exterior cross groove-s 47, which are intersected by the trunnions 92 for the wrist pin 93. The flat outer ends of the trun- 115 nions 92 provide spaces 94 for oil, which 6pen into the adjacent ends 6f the cross grooves 47 to irisure proper distribution of the oil in all directions above, below, and around the exterio.- of the piston in opposite directions, as well as to 120 the interior of the @ wrist pin 93. For supplying oil to these parts of the piston, the latter is provided with an exterior circumferential oil groove 95, which extends entirely a-round the piston, and intersects the oil space 125 94. At one side, the oil grgove 95 opens into a verticall y disposed slot 96 formed in the outer surface of the lower uart of the piston 89, and - which is adapted to register with an oil feeding conduit 97 for supplying oil under pressure, the 130 groove 96 registering with the conduit 97 when the piston is in 'its lowermost position. This groove 96 is closed at its opposite ends, and not orily opens into the annular groove 95, but also into the adjacent portions of the cross grooves 47. 135 This in.,ures a quick and even distribution of the oil under pressure, which is delivered through the pressure conduit 97. Refer ring now to the diagrammatic illustration shown in Mgure 24, the bady 98 of the pis- 1--o ton is providied with a ring groove 99, which is ,@ubstantially three times the width of the groove at present constructed in pistons, and which is sho-,vn to bdvantage in Figure 22. The oppc7ed walls of the groove 99 are disposed substantially 115 in parallel relation, as indicated by the line3 100, w-lien the piston 98 is to be subjected to-relative!y high temperatures, such as in airplane motors, compressors of high compre@sion type, and the like, and where the ringgroove 99 is located near 150

the upper part of the pisto.n 98, as shown in Figure 22, and where the rings are subjected to intense heat. The reason for this construction is that the substantially parauel walls 100 ofler but little resistance to the contraction of the rings when they are forced back into the groove 99 by expansion, and it is necessary in this type of engine and with grgoves in the uprier part of the piston, to offer as little resistap-ce as possible to 10 this contraction. As shown by the lines 101, the side walls of -the groove 99 may be diverged slightly where temperatures are not quite so high, and where the ring grooves 99 are spaced downwardly from the up15 per end of the piston, and toward the source Of lubrication. The lines 102 indicate a further divergence in the side walls of the groove 99, and this indicates the use of this type of groove for lowertemper,a20 tures, or at points nearer the point of distribution of the lubricant. In a like manner, the lines 103 indicate a further divergence in the side walls of the ring grooves 99, showing that the divergence is propor25 tionate to the temperature and to the location of the ring groove. with respect to the source Of lubrication. As shown in Figure 22, the straight wall groove 99 is near the upper end of the piston, and by use 010 of t.he wedge section,76, the spaced sections 41 are held outwardly against the opposite sides of the groove, and are also maintained in an OutWardly expanded position. The parallel walls 100 of the groove and the outer parallel walls 33 of the sections 41 offer but slight resistance to the compression of the ring as a unit without disturbing the spread relation of the sections 41. of course, the wedge section 76 may be given any desired taper corresponding to the inclined 40 walls indicated in Figure 24. The innermo@,t ring groove 75 is preferably provided with the outwardly flaring walls, as shown in Figure 22, so that the ring will bear witl@ greater pressure and resistance against the side waU of the cylinder 43 30, and any seepage of the gases of combustion, or of the lubricant past the sections 41 is.vented through the wedge section 76, into the groove 75, and through the openings 78 to the interior of the piston 98. 5o Of course, any desired arrangement of the ring grooves may be used, and the ring groove 75 may be graduated as to the flaring of its walls. It will be obvious that many changes in the construction, combination and arrangement of 53 parts could be made, which could be used without departing from the spirit of my invention, and I do not mean to limit the invention to sue h details, except as particularly pointed out in the claims. co Having thus described my invention, what I claim and desired to secure by