US1817388A

US1817388A - Method and apparatus for casting journal boxes

Info

Publication number: US1817388A
Application number: US340477A
Authority: US
Inventors: Lee W Melcher
Original assignee: Fafnir Bearing Co
Current assignee: Fafnir Bearing Co
Priority date: 1929-02-16
Filing date: 1929-02-16
Publication date: 1931-08-04
Anticipated expiration: 1948-08-04

Description

Aug. 4, 1931. w..MELcHER 1,317,388

METHOD AND APPARATUS FOR CASTING JOURNAL BOXES Filed Feb. 16. 1929 Patented Aug. 4, 1931 i UNITED sTAfrEs;

PATENT ori-ics LEE W. MELClHER, F DE PERE, WISCONSIN, ASSIGNOR-*TO FFNIB BEARING COIPAN'Y, 0F NEW BRITAIN, CONNECTICUT, A CORPORATION OF CONNECTICUT. f

nn'rnon im Armures ron cas'rme JOURNAL ,noxes- Applcation filed February 18, 19,89.' Serial No. 840,417.

The invention relates to casting journal boxes for roller-bearings. In these boxes it isadvantageous vto forman integral cylindrical wall having -a bearing surface for the rollers to avoid the ne'essity of a separate hard metal bearing sleeve. It is also advantageous to form. the upper ortion or load zone ofthe integral wall o hard metal in order to resist wear.

4 character, it is necessary that the load zone of hard metal in the cylindrical 'wallsh'ould be of suicient thickness to form a structure which will be reliably resistant to wear for 16 a long period of time, after it has been v ground or finished. One object of the prese'nt invention is to provide an improved method of producing journal boxes in which the load zone of the cylindrical wall will be 20 hardened and of suilicient depth to withstand efiiciently wear.

Another object of the invention is to provide an improved method of producing journal boxes of this character, in which the impurities in the molten metal are-kept awayfrom that portion ofthe cylindrical wall in which the load zone is formed and are caused to accumulate in a portion of the box which is notused as a(bearing surface.

A further object of the invention is to provide an improved method of casting journal boxes in which the sides and top of the journal box, as well as the pedestal guides and equalizer seats are formed of hard metal.

A still further object of the invention is to provide a?) improved mold for use in casting journal oxes having an integral cylindrlcal bearing wall.

Other objects of the invention vwill be apparent from a considerationof the following detailed description.

The invention consists in the several novel features hereinafter set forth and more par! ticularly defined by claims at the conclusion hereof. y f 'f A.

In the drawings Awhich accompany and form a partei this specification or disclosure and in which like numerals of reference de-y note corresponding parts throughout the several'views; Fig. 1 is a section of a mould In journal boxes of the aforementioned.

showing the preferredy manner of carrying outl the invention. Fig. 2 is a section 'taken' on the line; 2--2 of Fig. 1. Fi 3 is a section of the journall box produced y the present method and in the improved mould.

v The invention is exemplified in assembling certain cores in a flask which` comprises a cope 4 and a drag v5. The flask is first placed von a bottom-board 6. A bed 7 of sand is then packed on said board. A dry-sand core 8,

which has its top face shaped to form thel bottom a of the journal box ais then placed upon the sandbedv?. Chill-sections 12, with dry-sand cores 13 baked on the outer sides thereof, are laid on the bottom-core 8. These sections 12 are shaped and spaced apart to cause a layer a2 of hard metal at the side-` faces a of the box a, and are provided with vertical grooves 14 in their inner faces, to form hard-metal pedestal guides'as on the sides of the box. Dry-sand cores 9, which are sha a, are p ated on the bottom-core 8 and across the ends of the chill-sections 12 and cores 13.

A cylindricalA opening a". is formed in the box to provide an integral 'correspondingly cylindrical bearing-Wall ai.' or race 1n the box a, for a series of rollers around an axle in the box. This wall a1 is formed by a composite core whichis held in prints in and extending across the space between the end-cores 9. This composite core consists of a chill-section 18 and a dry-sand section 19 which are baked together and have their peripheral portions shaped to form the cylindrical opening a in the casting. The periphery 18s of chillsection 18 extends throughout less than 180,

preferably about 160, of opening a, to form ahard-metal zone a of corresponding area which constitutes the load zone of the bearing wall a. Dry-sand section 19 forms the remainder of the wall a' of soft metal. The bottom face of chill-section 18 is recessed, and sand section 19 extends into the recess, so the two sections will remain corelatively positioned to form truly the opening a. The composite core is' positioned so the axis of opening a will be horizontal and the chillsection 18 is placed at the tog, for the purpose hereinafter described. rysand cores d to form the end-walls of the box 2O are held in core-prints in end-cores 9 and extend longitudinally across the space around a hard metal face, a on the top 'of the box a, i

and has a recess 15 to form a Yhard-metal equalizer seat a on the to of the box, and cross-grooves 15l to form ard metal guideribs alz for the equalizer bar, at the ends of seat a. After the parts of the mold have been assembled in the flask, the s ace 7 beimv ` a comparative tween'the walls of the fiask an the sidecores 13 and end-cores 9, is filled with -sand so that the mold will be surrounded by sand to permit expansion of the parts of the mold. A vertical 4gate 23 extends downwardly f through top-core 15'* and one of the side cores 13 to a horizontal te 24 4in vbottomcore 8 below chill 12. e gate 24 is connected by a' restricted upwardly extending gate to the space which is to be filledwxt metal.v One or more gas vents (not shown) extend through the chill 15 and core 15".

In practice it has been found that if the l metal is permitted toA boil or to be excessively a 'tated dur the rocess of urin only g1 mf thiii film of xliiztal vgvill be hardened by t e chill-sections so that'the hardened zone will not be effective to revent wear particularly on the cylindrical ring surface. It has also been found that when the temperature of the various chill-sections is too low, the metal will boil or agitated excessively and displace the previously derenheit at the commencement of the I agitation which results from the posited portions on the chill-section, andto minimize this, the chill-sectionsare heated a roximately to 180 Fahrenheit. The c ills are heated to somewhat higher teinperature before they are placed in the mold, and the period of pouring with respect to the closing ofthe moulds is timed the temperature of approximately180 Fah- .umg operation. All rts ofthe moul which form soft metall-m portions of the box are formed of dry-sand cores, to minimize the production by\mol'sture in the mould. en the mould has beenp'repared as set forth, the molten metalat approximately 2500 Fahrenheit is poured into the gate 23, fromV which it flows through the gate 24 and then upwardly through the restricted gate 25 into the bottom ofthe space in which the box is formed. In pouring, a constant supply of molten metal is maintained in the down-gate by reason of the restriction'in the edge ofthe chill-.section '18, it progressively flows over the eripheral faceof the chillsection 18,v and) the subsequently incoming metal will riseadjacent the side chills without displacing th'e metal which has been previously deposited on the periphe of chill-section 18. In practice it has en found that any flow of the molten metal over reviously deposited metal on a chill will ave the effect of reducing the thickness of the hardened zone. ,x As a result, the zone of metalhardened by the chill 18 will be of suiiicient thickness, for examplee 1% of an inch', to form an effective hard metal bearing surface in the load zone in, and integral with, the cylindrical bearing wall. The impurities in the metal, by reason of avoiding excessive agitation, will remain on the top of the flux and accumulate at the top of the a5 box and will not be deposited ,on the loadl zone of the cylindrical wall. This is iinportant, because the presence of impurities in 'the load zone is objectionable, while their presence' is not objectionable in 100 the top of the box which is not used'as a bearing surface. During this pouring,

the metal flows upwardly between. the4 constricted .portions of the spaces at the sides of the core 19 and the chill 12, and, as 105 a result, the zone of hard metal at the central side portions of the box may be somewhat irregular in de th or narrower than the hard metal in the oad zone of the cylindrical wall. This however is of no moment, no because such portions of the box are not subjected to great wear. The pouring of the metal is continuedy until the'entire space in the mould has been filled. Chill-section 15 forms a hard metal portion on which the 115' equalizer seat is formed so that it will resist wear. The 'chill-sections 12 harden the metal in the sides of the box and in the pcd-- estal guides to render them wear-resisting.

' In cooling, the expansion of the metal will 12o contract the openin a and force the chillsection 18 downwar 1y and toward the cen-A ter of the cylindrical wall and will crush the sand-core 19. This eliminates shrink cracks z and distortion of the cylindrical wall of the box which would otherwise result from .the

.expansion of the metal and contraction of the 'cylindrical wall, and also facilitates the Aremoval of the chill.

The invention Yexemplifies a method of 131* which consists in preparing a mould with a' casting journal boxes with an integralcylin- .d riealv wall for a bearing surface with a hardened portion in the load zone of sufficient thickness to be effective and to rmit the necessary finishing or grind' t also exemplifiesa casting method l:vich roduces a load zone of hard metal in the cy indrical Wall of uniform thickness and comparatively free from defects caused b impurities in the metal. `It also exempli es an improved method by which uniform castings will be produced at a low cost.

The inventionpis not tol be understood as restricted to the details 'set forth, -since these may be modified within the sco of the a pended claims, without` departing from t e spirit and scope .of the invention.

' I claim as new and desire'to secure by Letters Patent, is:

`1. The method of casting a journal box having an integral cylindrical bearing wall, which consists 1n reparing a mould with a chill section sha e to form a hard metal load zone in said cy indrical wall and arranged so that its periphery faces upwardly and extends horizontall and with a core to form the remainder o the cylindrical wall, and pouring metaly from below into the cavity around the core and chill section so it will flow upwardly and progressively over the peri hery ofthe section-to form the hardene load zone without displacing any substantial portion of the metal previously deposited on the chill-section.

2. The method `of casting a journal'box having an' integral cylindrical bearing wall,

chill-section shaped to form a hard metal load zone of less than 180 in said cylindrical' wall, arranged so that its peri hery faces upwardly and extends horizontall) and with a core to form the remainder o 4the cylin drical wall, and pouring mtal vfrom below into the cavity around vthe core and'chill member so it will flow upwardly and progressively over the periphery of the section to'form the load zone Without displacing any substantial portion of the metal previously deposited on the chill-section and cause said zone to be comparatively thick.

3. The method of casting a journal box having an integral cylindrical bearing wall,

- load zone in said cylindrical wall and arthe periphery of the sectlon and form the load zone without displacing any substanshape tial tportion of the metal previously deposited on e tluck chill-section so that it is comparativeiy d to formthe remainder of the cylin-, drical wall of soft metal'and adapted to permit the ,chill-section to be forced toward the center of the opening by the expansion of the metal, and pouring metal from below into the space around the core and chill-section, so it will progressively flo w over the periphery of the chill-section without displacement.

5. The method of casting a kjournal box having an internal cylindrical bearing wall, which consists in preparing a mould with chill-sections shaped to form the sides of the box, a chill-section shaped to form a zone of hard metal of less than 180 in the cylindrical wall with its eriphery facing upwardly, a sand core to of the box, a cylindrical chill-sectionshaped f toy form a zone of hard metal of less than 180 in the cylindrical wall, a dry sand core to form the remainder of the cylindrical wall and a dry sand core to form the bottom of the box of soft metal, and pouring metal from below into the cavity around the first mentioned core and between the chill-sections.

7. The 'method of casting a journal boxl having an integral cylindrical bearing wall, which consists in preparing a mould Awith chill-sections to form the sides and top of the box, a cylindrical chill-section shaped toA form` a zone of hard metal in the cylindrical wall, and a dry-sand filling to form the bottom of the box of soft metal, and with cores to form bolt holes extending through the box, and pouring metal from below into the cavity around the core and between the chillsections.

8. The method of casting a journal box having an integral cylindrical bearin wall, which consists in preparing a moul orm the remainder of the\ cylindrical wall, and pouring metal from f ics with l chill sections to form the sides, a chill-section to form the top of the box having a. recess therein to form an equalizer seat of hard metal, a chill section shaped to vforma zone of hard metal in the cylindrical wall, asand l core to form' the remainder ofthe cylindri- 50 j arranged with the chill-section on the top -zone of hard metal in the cylindrical wall, and

means forming a gate leading upwardly to the space below the core.

10. A ymould for a journal box having an integral cylindrical bearing wall, comprising a flask, a chill section and a sand section united together to form a composite core and arranged with the chill-section on top and in the mold cavit so as to form the cylindrical bearing wall or the box with a. hard metal upper zone, chill sections shaped to formv the sides and top of the box, a dry sand core to form the bottom of the box, and'means in the flask forming a gate leading upwardly to the space below the core. l y

11. A mould for a journal box having an integral cylindrical bearing wall, comprising a flask, a chill-section and a sand section united together to form a composite core and arranged with the chill-section on the top and in the mould cavity so as to form the 'cylindrical bearing wallfor the box with a' hard metal upper zone, chill sections shaped to form the sides of the box, a chill section shaped to form the top of the box, having a recess to form an equalizer; seat of hard metal, and means in the flask forming a gate leading upwardly to the space below the core.

12. A mould for a journal box having an integral cylindrical bearing wall, comprising a flask, a chill-section and a sand section united together to form a composite core and arranged with the chill-section on top and in the mould cavity so as to form the cylindricalbearing Wall for the box with a. hard metal upper zone, chill-sections to form the sides of the box, a dry-sand core to form the bottom of the box, dry-sand cores to form the ends of the box, and a gatev in the bottomcore.

'13. A mould for a journal box having an integral cylindrical bearing wall, comprising a flask, a chill-section and a sand section united together to form a composite core and and in the mould cavity so as to form the cylindrical bearing wall for the box with a hard metal upper zone, chill sections to form the sides/of the box, ay dry-sand core to form the bottom ofthe box, dry-sand cores to form the ends of the box, a chill-section to form the top of the box, and a gate in the bottom core.

L4. A mould for a journal box having an integral cylindrical bearing wallcompr1sing1 a flask, a chill-section and a sand section united together to form a composite core and arranged with the chill-section on the top and in the mould-cavity so as to form the yday of January, 1929.

cylindrical bearing wall for the box with a hard metal u per zone, chillesections to form the sides of t e box, a dry-sand core to form the bottom of the box, dry-sand cores to form the endsof the box, dry-sand cores backing the side chill sections, and a gate in the bottom core.

15. A mould for a` journal box having an integral cylindrical bearing wall, comprising a flask, a chill-section and a sand section. united together to form a composite core and of the'box, dry-sand cores to formthe ends of the box, a chill section to form the top of the box, dry-sand cores backing the side top chill sections, and a gatein the bottom core.

16. The combination of claim 14 with a filling of sand under the bottom cbre and around the side and end cores.

1,7. Thercombination of claim 15 with a lling of sand under the bottom core and around the side and end-cores. q

Signed at De Pere, Wisconsin, this 28th LEE W. MELCHER.