US2670251A - Adjustable bearing guide for lineally movable shafts - Google Patents

Description

Feb. 23, 1954 v M. c, TRlBBET-r 2,670,251

ADJUSTABLE BEARING GUIDE FOR LINEALLY MOVABLE SHAFTS Filed Oct. 4, 1950 A uuuu u:

INVENTOR M at 91275822 ATTORNEY Patented Feb. 23, 1954 UNITED ZFSI CE i 2,670,251 ADJUSTABLE LBEARIN G "GUID-E'FOR LiNEALIZY MOVABLE "S'HZXFTS Murrayfi. Tribbett, -Mount :GileadQOhi-n, rassig nor to -.H-PM Development Corporation, "li'ii'onnt Gilead, Ghiu, a corporation of Delaware Anpii catiowilctdber 4, 1950, Serial *No. 188F139 --2 Claims.

2i FIE-he present invention relates "to -shaft-.-guiding means, and whilemot being so limited, has par- *ticular reference to an improved -=beari-ng .-;guide for the reciprocating rams of hydraulic presses.

The "usual hydraulic press comprises a stat-ionary press bed, an elevated press head which carries a suitable hydraulic fiuid actuated -rec-iproeating ram, and a plurality of strain rods-\orsta tionary 'frameimembers extending between the .press head :and bed to :absorb separation orces impartedto the .press head and bed during the operation cfthe reciprocating ram. in the usual *manner, the -reciprccatin-g ram carries at its lower end a press vplaten cooperative with astationary die-supported :cn .thepress bed. Generally, the press platen is guided its reciprocating movement by means of .a plurality of corner .g'ibs which are slidably connected with the strain rods or spaced stationary Tirame [members of the p ss disp d on pposite sides of the ress platen and ram. It will be understood that in press operations it is absolutely necessary "that the .press platen and press ram follow'a's'traight lineltravel in order 'th'at'the co'mplemental sur- "faces oi'fthe'pr'ess platen anddie'may be brought into exact alignment during "the pressing stroke to impart the desired configuration to a workpiece. Due to the relatively extreme forces and the :size and weight "of the elements "of the "ordinary press, considerable difficulty has "been encountered with the ordinary type of g'ib guide due to its inability "to "compensate for the nor- *mal wear encountered during prolonged press usage. Further, it has been found that in press assemblies wherein"the-outercornersbi the press platen are provided with gib guides engaging the associated strain rods "or vertical s'tanohions of the press, it is diificult to eliminate the normal tendency of the press platen *to Wobble "laterally during reciprocating movement, due tothe reiative spacing between'the axis nf-the ram and the faxes or the 'gib guides disposed at the extremities of the "press platen.

Accordingly, it *is 'the primary object of the present invention to provide an im-proved bear- I .ing :blocks and "adjustable "to vary theiefiiective size of "the C'lKOILIE I :opening :deiined by said :blocks, whereby to compensate zior the inorma'l wear 0f the hearing blocks :and thereby prevent undesired :radial displacement of an associated shaft during its iong itudinal :movement.

For a vfurther and more ade'tailed .aunders'tandzjing @Of the present invention :and the Nations additional'objeots'iand advantages realizedfthenefrom, reference :is made toithe ifollow-ing description and the accompanying drawings, wherein:

Fig. 1 is racside elevational yiew of'a'hydraulic press utilizing the present improved bearing guide;

Fig. 2 .;is a horizontal sectional view taken through the bearing iguid'e 1310118 the line 2- io'f Fig. :1

Fig. 8 .5.5 :a similar view shaken along ithe -iline (Ii-+3 oiiEig. 11 .andshowiing :in detail ithe aaidqiust- "in'g sc'rewzs afo'r the iind iviidualigibs :of the present bearing :guide.

:Fig. 4iis an enlarged efragmentary horizontal sectional "view illustrating in idetail .the gib a'd- -dusting means :of :the present :bear'ingaguide.

Referring now to the zdrawings, the :numera'l H! designates the istationary rbed 20f :ashydraulic :press zupon *which is mounted :a :stationary cma-le @clie member 1| 1. Arismg wertically fcn'zeither of the bed iii! is ;a v:pairzof relatively spaced stationary iframeimembers M which supportnt their uppernendsitheahead xlr3 of thepress. 'tlereierablv, as shown in d'etail in :Eigs. 2 r and :3, the ts'tationany .=frame members 12 ref the ;press were each formed to ieons'titute an outer :shell casingtifl through whichiextend :a pair of :solid strain mods #25 which, tin athe 'ausual manner, :are ibclted, or :otherwise suitably secured, :at their respective ends to the bedmndahead fioi the zpress'to :absorb strain forces imparted during pressing eneraitions. The-casing ii'dsurrounding the-tsitrain'rods i .5:;is slikewise suitably irigidly secured iboth toathe strainirods IE5 and "to the J bed and head elements .of therpress toi prevent relative movement :oi foyerall stationary frame members 12. :As will -be :seen particularly from :Figs. :2 an'd 310i the drawings, each-casing M is formed intermediate its ends with inwardly directed bosses .WhiflhlBI-JB J bent to form a relatively wide rectangular channeled recess 16, with the individual recesses of each casing being opposed so as to define a substantially rectangular chamber surrounding the intermediate portion of the reciprocating plunger or ram ll of the press. In the usual manner, the head l3 of the press supports the main hydraulic cylinder l8 into which fluid pressure is introduced to reciprocate the ram [1. Also, the head I3 supports the various valves, pumps, reservoirs, and other control apparatus necessary to the actuation of the press ram. The ram I! of the press carries at its lower end a press platen [9 which, in the present instance, carries a female die which cooperates with the stationary die H to impart to a workpiece the desired configuration upon a pressing stroke of the ram H. To guide the ram and the platen E9 in their vertical travel, there are positioned within the rectangular opening defined by the recesses it formed in the stationary frame members I4 of the press, four separate bearing blocks 20 which are formed on their inner surfaces with armately concaved bearing surfaces 2 1. Each of the bearingblocks 20 is formed with right angularly disposed outer side walls 22 which are arranged to fit within the corner regions of the recesses 16 formed in the stationary frame members M.

As shown in Fig. 2 of the drawings, each of the of movement of the ram 11, or, in other words,

to prevent movement of the blocks relative to the stationary frame members [2 in response to movement of the ram l1. Further, rotational movement of the ram I1 is prevented by means of a longitudinally disposed key 24 extending radially inwardly from one of the blocks 29 into a channeled groove 25 formed in the outer surface of the ram [1.

Each of the bearing blocks 20, on its outer sides, is formed with circular recesses 26 which receive the inner headed ends of relatively spaced set screws 21. The set screws 21 are carried in screw-threaded openings formed in the casing 14 and are provided at their outer ends with screwdriver-receiving slots by which the set screws may be rotated to urge the individual blocks 20 to move radially inwardly with respect to the ram IT. The recesses 26 formed in the outer walls of the blocks are relatively larger than the heads of the set screws to permit compound radial movement of the blocks when the separate set screws disposed in right angular relation to one another are tightened to crowd the blocks into tight engagement with the ram 11. There is also provided in association with each set of set screws 21 an adjustable cap screw 28 which extends through a slotted opening 29 formed in the wall of the casing I4 and threadedly engages the block 20. Each block is provided with two cap screws disposed in right angular relation to each other and between the two set screws 21. opposed to that of the set screws 21 in that tightening of the cap screws 28 serves to draw the individual blocks 20 radially outwardly with respect to the ram 11 in opposition to the action of the set screws 21 which forces the blocks inwardly. In this manner, when it is desired to tighten the blocks 20 against the periphery of the ram II, the cap screws 28 are loosened prior to the adjustment of the set screws 2? which, in turn, are tightened inwardly of the blocks an The action of the cap screws 28 is even amount to displace the blocks 20 radially toward the ram until a tight fit is obtained between the bearing surface 2| of the blocks and the segment of the outer periphery of the ram engaged by the blocks, at which time the cap screws 28 are tightened to draw the blocks into tight engagement with the headed ends of the set screws 21 and thereby to lock the blocks in their adjusted positions.

Access to the individual set screws 21 and cap screws 28 may be had by way of slotted openings 30 formed in the outer wall of the casing M in registration with the ends of the set screws and cap screws. Thus, the individual blocks 20 may be adjusted with facility without in any way disassembling the component parts of the press, whereby to assure a close fit between the bearing surfaces 2! of the individual blocks and the outer periphery of the ram II. It will be understood that tight clamping forces between the blocks and the outer surface of the ram are undesirable, yet at the same time, the outer peripheral surface of the ram [1 should be closely engaged by the bearing surfaces 2! of the blocks in order to prevent lateral displacement or wobbling of the ram l! in its upward or downward movement during press operations.

Bearing guides formed in accordance with the present invention provide generally increased bearing surfaces between the stationary and movable members of the press, while at the same time permitting accurate adjustment and compensation for wear within the bearing blocks or gibs. Further, due to the fact that the present bearing guide is arranged to guide the reciprocating ram of the press, rather than the relatively wide platen of the press as is the usual case, the moment arm between the axis of the ram and the bearing surface of the guide is greatly decreased, thereby minimizing the wear upon the individual gibs of the guide.

I claim:

1. In a bearing guide for a linearly movable cylindrical shaft; a stationary frame defining a chamber of rectangular cross-sectional configuration about an intermediate portion of the shaft; a plurality of bearing gibs carried by said frame within said chamber for limited radial movement with respect to the shaft, each of said gibs being formed with an arcuately concaved bearing face for close fitting engagement with a segment of the outer surface of the shaft and a pair of right angular side walls disposed in adjacent relation to a corner region of said chamber; set screw means threadedly carried in said frame and engaging the separate side Walls of each of said gibs, said set screw means being adjustable to move said gibs from the corner regions of said chamber radially inwardly toward the shaft; and locking means for holding said gibs in radially adjusted positions with respect to said shaft comprising screw-threaded members rotatably carried in said frame and threadedly engaged with each of said gibs at each of the side walls thereof and adjustable to draw said gibs radially outwardly with respect to said shaft and toward the corner regions of said chamber and into tight engagement with said set screw means.

2. In a hydraulic press; a hydraulically actuated reciprocating ram; a pair of relatively spaced stationary frame members disposed on opposite sides of said ram and spaced therefrom, said frame members defining a shaft-receiving chamber of generally rectangular cross-sectional configuraiton; a plurality of guide blocks carried by said frame members in each corner of said chamber and having bearing surfaces thereon conforming to a segment of the outer periphery of said ram, each of said blocks being keyed to one of said frame members to prevent movement of said blocks relative to said frame members in directions parallel to the axis of said ram, but permitting limited movement of said blocks radially inwardly toward said ram and being formed with right angular side walls adjacent said frame members; a plurality of set screws threadedly carried by each of said frame members and abutting each of the side walls of said blocks and adjustable to move said blocks radially inwardly toward said ram to bring the bearing surfaces of said blocks into close conformity with the outer 6 periphery of said ram; and a plurality of locking screws threaded into each of the side walls of said blocks and adjustable to move said blocks radially outwardly with respect to said ram and thereby to tension said blocks against said set screws.

MURRAY C. TRIBBETT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 421,856 Case Feb. 18, 1890 675,241 Pederson May 28, 1901 1,122,409 Mumford Dec. 29, 1914 2,337,984 Flowers Dec. 28, 1943 2,342,946 Le Tourneau Feb. 29, 1944

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