US1444259A - Process of sizing and quenching - Google Patents

Description

Z SHEETS--SHEET l.

M. T. LOTHROP.

PROCESS 0F SIZING AND QUENCHING.

FILED fEB.5,1921.

Feb. 6, 1923.

Feb. 6, 1923. v 1,444,259. Nl. T. LOTHROP.

PROCESS 0F`S|ZING AND QUENCHING.

FILED FEB.5.1921. 2 SHEETS-SHEET 2.

Wg A i zal? afffeffff.,

fPatentedFeb. 6, i923@ i:

carica.

immens fr. Lorano?, or CANTON, omo, assreNoN 'ro 'ma 'tirannie norma Barrie COMPANY, or CANTON, cmo, .a coaroaa'rron or omo.

BROCESS F SIZING AND QUENCENG.

Application led February 5, 1921. Serial No. 442,737.

To all 'whom t may concern.' most position, said expanding member being Be it known that I, MARCUS T. Lo'rHnor, shown in elevation and the cone and other a citizen of the United States, and a resident portions of the apparatus being shown in 55 of the city of Canton, in the county of Stark section;

and State of Ohio, have invented a new and F ig. 2 is a vertical section of the parts 0 useful Improvement in Processes of Sizing apparatus illustrated in Fig. 1, Wiith the ex' and Quenching, of which the following is a panding member at the downward limit of specification. its stroke; 60

Accordingl to present practice, hardened I Fig. 3 is a view similar to Fig. 1 and Fig.

metal articles of annular section, such for 4 'is a view similar to Fig. 2, but with the instance, as cups and cones for roller bearexpansion me'mber shown in the form of a ings, are first shaped and sized in any suittapering plug adapted for use in the manuable way and afterwards heated and facture of a roller bearing cup; and 65 quenched for the purpose of hardening Figs. 5, 6 and 7 illustrate modifications them; and distortion is so common an inciof such apparatus suitable for restraining dent of the hardening operation that the the cup both interiorly and exteliiorly durhardened article usually requires to be ing the quenching operation. ground to correct the distortion, notwith-` While my invention is applicable to the 70 standing that grinding is expensive and immanufacture of' other articles, I will first depairs. the article. The principal objects of scribe it in connection with the manufacture the present invention are todevise a cheap of cones for roller bearings. and simple 'method of sizing the article, to The stock, which is preferably steel is first overcome the tendency' of the hardening opworked by ordinary metal cutting or forg- 75 eration to distort the article, and to miniing operations into a green article of submize or eliminate Vthe need for grinding or stantially the sizeand shape required for like finishing operations The invention conthe final product, but with its bore of slightsists principally .in making the article of ly smaller diametei'. This green article is green or unhardened metal of approximatethen heat treated in conformity with current 80 ly the shape and size required for the finpractice or in other suitable manner; but

ished article but of vslightly smaller bore, instead of being. quenched as it comes from heating said article, expanding the bore the furnace, it is submitted to an operation thereof to a diameter slightly iin excess o-f that quickly stretches 'the metal circumferthat required for the vfinished article and entially to enlarge its bore slightly in excess 85 keepingl the bore so expanded during the of that required for the finished product,

quenching operation. It also consistsl in and it is then immediately quenched without mechanically stretching the heated article releasing the circumferential tension or and quenc-hingthe same without appreciable stretching force. time interval after such stretching. It also Referring to Figs. 1 and 2 of the accom- 90 consists ln'mechanically creating circumferpanying drawing, A represents a. Agreen cone 40 ential tension in the hot article and quenchfor roller bearings made in any suitable way ing the saniewithout relieving such tension. but with its bore of slightly less diameter lt also-,consists in the operations hereinafter than required for the finished article'. This described and claimed. green cone is heat treated, in accordance 95 In the accompanying drawing, wherein with common or other suitable practice; and,

like numerals refer t0 like parts wherever immediately upon its removal from the they occur, hardening furnace, is set on a suitable seat Fig. lV illustrates portions of apparatus 1 provided therefor on the bed plate 2 of a suitable for practicing -my process in conpress whose plunger 3 works up and down in 10o nection with the sizing and quenching of alinement with said sea-t.` The bed plate 2 cones for roller bearings, such a cone 'bein-g is provided with an elongated wedge block shown in positiondto be operated on by the 4 in axial alinementfwith the plunger and expanding member which is in its upperpreferably in the form ofan upwardly tapering cone. The head of the plunger iS provided withr an Vexpansion plug 5 comprising a plurality of elongatedsegmental portions 6 which are illustrated as beingmtegral with the base of said plug and being separated from one another by longitudinally extending slots, T. of said segments are concentric and of the curvature required to produce the desired expansion of the bore of the hea-ted article; that is. the surfaces of the segments. when fully expanded radially. are concentric with the axis of the wedge block 4 and of the plunger 3 and have a radius slightly in excess of that desired for the finished article. T he inner surfaces of said segments are tapered as illustrated at 8, and shaped to cooperate with the tapered Wedge block 4; and the parts are so related that the downward movement of the plunger Will cause the inner surfaces of said segments to bear against and be spread radiallyJ outward by the Wedgng action of the wedge block. By this arrangement, the hot bearing cone that surrounds the wedge block 4 and rests on the seat 1 provided therefor on the bed plate is in position to permit the expanding segments t-o entera considerable distance Iinto the. bore of the hot cone before any expanding action occurs; while the further downward movement of the plunger causes the segments to spread .outwardly against the inner Wall of the cone and enlarge the bore thereof. As stated above. the parts should be so adjusted that. when`the segments are fully spread. the bore of the hot cone. will be slightly greater than that required for the finished article.

This operation of expanding the bore sets up a circumferential tension in the metal of the cone; and it is very advantageous to quench the cone without any appreciable interval of time after such enlargement of the bore and Without relieving the cone from the force that expanded it. For this reason. the quenching system is so disposed and timed segments that the quenching fluid is brought into operation simultaneously with completion of the expanding operation.

For the purpose of quenching, the seat for the hot cone is surrounded by an annular wall t) which forms with said seat a quenching well or chamber. This Wall has a multiplicity of pavssigewayys 10 extending longitudinally through the bottom thereof and communicating through an annularv channel 11 and a bore 12 and a pipe 13 with a source ot' quenching fluid. Each of said' passageways 10 in the Wall of the quenching Well communicates with the interior of said Well through -iet openings 14 in the inner face of said wall: wall is provided with a multiplicity of holes 15 for draining the quenching fluid from The outer surfacesA with relation rto the expanding and the bottom portion of said said Well. The supply of quenching fluidis controlled by a valve 16 mounted in said bore 12 in axial alinement with the plunger/ of the press. This valve 16, which is adapt,-

ed to move up and down, is normally seated in its uppermost position, and it is adapted` to be actuated to open position by a downwardly extending rod 17 mounted on or movable With the head of the press plunger in position to bear against the stem 18 of the valve and thereby open the valve and effect the flooding of the quenching Well when the plunger approaches the downward limit of its stroke.

As the plunger moves with the usual speed of a power press plunger. the operations of expanding and quenching the cone are accomplished very rapidly and Without any appreciable time interval between them; and as the jets spray the entire circumference simultaneously and While the cone is still on the expansion segments, the resulting product is free from distortion. As the metal is under circumferential tensionl prior to quenching, and is quenched Without releasing such tension, its bore will contract slightly when the quenched cone is stripped from the expansion segments. It is 011 account of this slight contraction on stripping that the expansion segments are set so as to expand the bore of the hot cone slightly beyond what iswa ted for the finished article.

In the case'of a roller bearing cone with an axial cylindrical bore, the shrinkage in diameter is uneven on account' of thervariation in the thickness of the Wall; and if the wall of such cone is proportionately much thicker at the large end than at the small end, such uneven shrinkage will produce a -distinct taper of the bore from the narrow end of the cone towards the large end. While this taper due to shrinkage of a Wall of uneven thickness is slight, due allowance should be madev for it in determining the taper ofthe sizing plug on which a roller bearing cone is sized and quenched; that is, the taper of such sizing plug should be very slightly less than that desired' for the bore of the finished cone. A similar allowance should be made also for uneven shrinkage in the case of roller bearing cups and other articles whereinl the bore is conical and the outer surface-is approximately cylindrical or of considerably less taper than the inner surface. The effect of such allowance is to produce aigreater enlargement of the bore at the thick end of the article, where the integrity of surface.

shape of section and reat smoothness and l istortion is eliminated, grinding of the hardened article is made unnecessary in most instances, the full depth ofthe hardened-case portion is preserved and the'surface kis'sound and ready for use for bearing purposes.

lt is an important advantage of my process that the grinding of cups and cones for roller bearings and the like can be effected in their green or unhardened condition, as the subsequent hardening operations are effected under 'conditions Which tend to improve rather than impair the accuracy and soundness of the bearing surfaces. lt is noted that the process described not only sets up a plas/ticv flow fvvhi'ch lcauses the metal to conform accurately tothe shape of the plug or segment-s by `which it is expanded vand on Which it is quenched but that the v Withdrawal of such plug axially tends to planish or polish the surface thereof Without impairing its soundness.

Figs. 3 and l illustrate an apparatus like that of Figs. 1. and 2, but adapted for prac- `ticing my process in connection with the sizing and quenching of ,cups for roller bearings. For this purpose, the expansion member 'on the press plunger is not made of segmental form but is made inthe form of a continuous plug 5a of the taper desired vfor the inner surface of the inished cup of slightly larger size than required for such inishedcup. For the sake of quenching, the-outer surface of said plug is provided Witha multiplicityof longitudinally extendrooves 19 .that are slightly oblique or he ical and extend to the bottom of said plug Wherebyl said grooves communicate ywith the space 20 inthe quenching Well be-,f 10W rsaid plug and thence, through a passageway 21 in the seat la, With the supply 'system for the 'quenching fluid. `The operation of this apparatus is similar to that of the apparatus illustrated in Figs. l and 2; but it is noted that the quenching liquid is directed against both the inner and thev outer surfaces of said cup B simultaneously. Fig. 5 illustratesan `apparatus adapted to restrain the cup both lexteriorly and interiorly during the quenching operation.

4Said apparatus is-provided with a circular depresslon adapted to .receive the hot cup., 'llhe annular Wall of said-depression is provided With*a series-of helical grooves 191 which communicate with the passagevvays 10a through a series of jet openings 14a. rlhe v operation of the apparatus is similar to the operation of the apparatus shown 'in Figs. 3 and 4e; but it is noted that the cup is re- 4ing the quenching operation.

The apparatus illustrated in' Fig. 6 is provided"with a segmental holder 23, whose outer surface .is taperedto fit the tapered seat provided therefor in the Wall 9. The inner surface of the holder 23 is provided with a series of helical grooves 19b which communicate through jet openings 141 and passageways 10b with the annular channel 11. The operation of this apparatus is similar tothe operation of the apparatus shown in Fig. 5.

rlfhe apparatus illustrated in Fig. 7 is adapted for use in sizing and quenching cups Whose inner and outer surfaces are tapered. Said apparatus is provided With a conical depression Whose Wall is provided with a series of helical grooves 19 which communicate through jet openings 14C? and passagevvays 10c' with the annular chamber 1l.

1t is noted that the apparatus hereinloe-V fore described is simply typical and many changes may be :made-such as using solid plugsl or diferent forms of expanding plugs from that shown and l do not, therefore, Wish to be limited to any particular form of apparatus. 1t is further noted that by changing the form of the plug, my process may be made applicable to hollow articles Whose bore is not circular.

What 1 claim is: t

1. The process of treating articles of annular section which consists in forming them in the green, heating them and then circumferentially stretching the hot articles and quenching them While in stretched condition the operations of stretching and quenching being substantially instantaneous and performed soon enough after heating to prel vent appreciable cooling of the article.

2. The" process of treating articles of annular section which consists in forming such articles in the green, heating them and then mechanically creating a circumferential tension in the hot articles and quenching the hot articles While still under circumferential tension the operations of stretching and quenching being substantially instantaneous and performed soon enough after heating to prevent appreciable cooling of the article.

3.. The process of treating articles of annular section Which consists in forming them in the green,heating them and then mechanically creating a circumferential tension in the hot articles and immediately quenching them Without releasing such tension the operations of stretching and quenching being substantially instantaneous and performed soon enough after heating to prevent appreciable cooling ofthe article.

4. The process of treating articles of annnlar section, which consists in forming the article in the green,.heating the same, mechanically circumferentially stretching the same and quenching the same while so mechanically stretched and without appreciable time interval after stretching the operations of stretching and quenching being performed so soon after heating and so rapidly as to accomplish substantially instantaneous quenching and prevent appreciable cooling of the article prior to quenching.

5. The process of sizing and quenching articles of annular section Which comprises the formation of the article in the green with a slightly smaller bore than desired f or the finished article, heating the same, circumferentially stretching the heated article to enlarge its bore slightly in excess 'of the bore desired for the finished article, and immediately quenching the same Without releasing the circumferential tension the operations of stretching and quenching being performed so soon after heating and so rapidly as to accomplish substantially.instantaneous quenching and prevent appreciable cooling of the article prior to quenching.

6. The process of sizing and quenching articles of annularv section which comprises the formation of the article in the green, heating the same, circumferentially stretching the heated article to enlarge its bore slightly in excess of the bore desired for the finished article, and immediately quenching the same without releasing such circumferential stretching the operations of stretching and quenching ,being substantially instantaneous and performed soon enough after heating to prevent appreciable cooling of the article.

7. The process of sizing and quenching articles of annular section which comprises the formation of the article in the green With a slightly smaller bore than desired for the finished article, heating the same, circumferentially stretching the heated article by forcing an expansion member into the bore thereof to enlarge said bore slightly, and immediately quenching the same While still stretched on said expansion member the operations of stretching and quenching being substantially instantaneous and performed soon enough after heating t'o prevent appreciable cooling of the article.

8. The improvement in the manufacture4 of conical bearing cups and the like which A consists in forming the same With a diameter slightly less than desired for the product, heat treating the same, and While still hot forcing axially into the same a plug that has a portion of the diameter and taper desired for said product, the movement of said plug being continued after said portion lengages said cup to enlarge its bore slightly beyond that desired for said product.

9. The improvement in the manufacture of conical bearing cups and the like which consists in forming the same With a diameter slightly less than desired for the product, heat treating the same, and while still hot forcing axially into the same a plug that has a portion of the diameter and taper desired for said product until said portion partially passes its point of engagement With said cup and cooling said cup While.

.mined distance axially into a heated cup and then quenching said cup While inthe prep determined position on said plug, the outer surfaceof the portion of the plug in con- .tact with said cup in said predetermined position being of the taper desired for said cup but of slightly larger size.

11. The process of quenching cups for conical roller bearings which consists in heating said cups, restraining the same exteriorly and interiorly in grooved conical members that fit vthe inner and outer surfaces thereof and submitting the same While so restrained to the action of they quenching liquid introduced through the grooves, the restraining and quenching operations being so soon after heating andso rapid as to be substantially instantaneous.

12. The process of sizing and quenching articles of annular section, one of Whose surfaces is nearly cylindrical and the other conical, which comprises the formation of the article in the green with a slightly smaller bore than desired for the finished article, heating the same, circumferentially stretching the heated article to enlarge its bore slightly in excess of the bore desired for the finished article but more at the thick end than at the thin end thereof, and immediately'quenching the same Without releasing the circumferential tension.

13.` rlhe improvement in the manufacture of conical bearing cups and the like which consists in forming the same with a diameter slightly less than desired for the product, heat treating the same, and While still hot forcing axially into the same a plug that has a portion of the diameter desired for said product butnof slightly less taper, the movement of said plug being continued after said portion engages said cup tovenlarge its bore slightly beyond that desired for said product.

14. The process of making roller bearing cups and cones and the like which comprises the making of a green article grinding the bearing surface thereof to approximately the size and shape of the finished article, and with a smaller bore than the finished article, heat treating said article, expanding the heated article mechanically and quenching the same while mechanically reiso consists in forming the same with a diameter slightly less than desired for the product, heat treating the same, and While still hot forcing axially into the same a plug that has aportion of the diameter and taper desired for said product. I

16. The process 4of sizing and quenching cups for conical roller bearings which consists in forcinga tapered plug a predetermined distance axially into a heated cup and then quenching. said cup While in the predetermined position on said plug, the outerv surface ofthe portion of the plug in contact with said cup in said predetermined position being of the taper desired for said cup.

17. The .process of quenching cups for conical roller hearings which consists in heating said cups, restraining the Same interiorly on a grooved conical member that fits the inner surface thereof and submit-4 ting the same While so restrained' tothe action of the quenching 'liquid introduced through the grooves, the restraining and quenching operations being so `soon after heating and so rapid as to be substantially instantaneous.

18. The process of sizing and quenching articles of annular section, one of Whose surfaces is nearly cylindrical and the other conical, which comprises the formation of.

the article in the green With a slightly smaller bore than desired for the nished article, heating the same to enlarge its bore slightly in excess of the bore desired for the finished article but more at the thick end than at the thin end thereof, and immediately quenching the same Without releasin the circumferential tension.

igned at Canton, hiO, this 27th day of January, 1921. f

MARCUS T. LUTHROP.

Images