claim: 1. A pipe iiiachine h,,vving a 1:)acli:er sllaft 115 tpplica@le as liftiiig and a liydraulic ciirrent , ineaiis for raisino, the p,,Lcker shaft, and also operible at I'ligli speed to returii the -,haf L@ to neutr,,tl position. 2. A pipe m,,tchine coiiiprisinu a packer 12r) bead; a hydratilic lift therefor and a bypas8 valve by whicli the S,,tid lift is controlled in its up ,Lnd doivii iiioveiiieiit, aiid a relief vent limitino-, its upward moveiiient. 3. In ,t pip6 iua@hine, iii coiiibination , 11-5 hydraulic lifting rain iiith a p,iiiup O]perated by ,t mtin drive shtft; a pacli:er head, tiid means wbereby the pacli:er head is revolved by the iiiain ai@ive shaft and is, raise,-l and loivered by said liftiiig rams. 130

4. Hydraulic means for raising and lowerpacl@er shaft by operation of a valve so In thgtt Y"Lising or lowerino, Cali be controlled eitl.ier at top or bottom of travel of pack6r shaft or ,tt any point in between, means to relieve tl-ie pressure at a predetermined point, tlitis limiting the, upward movemelit oT said p,,Lcker shaft. I I 5. In a pipe n-iachilie a pael-,er shaft carry10 ing a, pac-ker head, hydratilic rain lifting ineans for directly raising ancl lo-%vei--ing the pacl@er shaft, and means connected to rot@ite draulic iiieans. said packer he,,td and to operate; the hy15 6. A concrete pipe u-iacliiiie coiiaprisingy a pacl@er hea(l; i-iieal'is to revolve the h,e-,id; hy_ drai,ilic ineans to lift and support the head'; and Rleans ivhereby the supporting meal'is illety be released nnd the head allowed to 20 drop by gravity at high speed to the level at ivhich the tro",ellilig and packing ope@ation is req-Liired to begiii. . . '@. A concrete pipe iii,,tchiiie coiiiprising a pacl@er heacl, i-iieans to revolve the head, hy25 draulic pressure i-neans to lift and siipport the head, means relielting said pressure ill the lifted positioii of said head, to hold said head tt ,t predeteriiained level, and means whereby the supportin- meaiis n-iay be re30 leased aild tl-ie head @llowed to drop 'by gtavity to the level ,tt whiel-i trowelling and paeldlig operations begin. . . 8 concrete pipe inael-tine coliiprisilig A a 3 packer head, ineans to revolve tlie, head, hyr) draulic pressure means to lift aiid support the he@id, autoiiiatic iiieans relievin- said presstire iii the liftecl position of sai(f hetd to hold sitid heacl at a predeteriiiined level: and iiieaiis @vhereby t@he, sup@portiiig means 40 nlay be rele,,ised and the head allowed to drop by gravity at Iiioh speed to th6 level at -NAbich troivellii-ig aiici pacliing operations begin. 9. A coiierete pipe machine coiiipi@ising a 45 packer Ilead, ineans to revolve the head hydratilic presstire meaiis to lift and support the head; a molcl, a pallet above said iiiold, iiieai-is to raise sa,id pallet froin said m6ld in tlie, raised positioli of s,,tid pacl@.er lietd, 60 me,,ti-is to relieve the presstire nieans ,ind thus i-ettirn the head to the level ,tt whicli pacl@-, i.no- o erations beuin. t, p 10. A concribte pipe, inachine coinprisilig liydi-aulic cylinders, pistons in said cylinders, r) 5 a packer sli,@if t, ineans coupling s,,tid pistolIS and said shaft, fluid pressure means actuit -ig s,,tid pistons, and a vent adjacent the ii movemeln.t of said pistoiis; a pallet, a inold under said pallet, aiid means cotipling said pistons and said pallet to lift s,,iid pallet in the raised p6sition of said pistons. 12. A concrete pipe@ macliine comprisino, 70 hydra-Lilic cylinders, pistons in said cyliliders, a paclier sliaft, nieans coiipliilg said pistons and saicl sh,,ift, fl-Liid pressure n-ieans actuating s,,tid pistons, ancl ,I, ient ,Idjacent the top of said c371inders to limit the upivard 76 moven-ierit of said pistons sl-id vent being operable by said pistolis. 13. A concrete pipe macliine comprising hydraulic cylincler,@, pistons in said cylindei@s a pael<@er slia-ft means coupliiig said 80 pistons-and saicl shaft ' fl-uid preSStLre means actuatih- said pistons, ,t housing in ivhicli said sl-iaft is slidably iiictinted, bearing means for sttid housing, and ineans to rotate said housilig. 810 14. A concrete pipe illacliine c6mpilisillo, hydratilic cylinders, pistons iii s,,tid cylillders, a packei,. sli,,tft, means coupling @ s,,iid pistons and said shaft, fluid @i-essu@e ineaus actuating said pistons, a liousiii(v in NA,I-iich 90 said sh@ft is slid,,tbly motintecl, bearing n-ieans f or said liou iii o-, and. iiieans operatinoto rotate E;aid liousin,,7@,' a7-id'also operating tno stipply tlle fluid iindei- pi-esstire. ; 15. " V con,crete pipe inacliine. compi-ising 95 hydraulic. cyliiidei-s, pistons in said cylindei-s, a packel- sliaft, iiieans coupling s,,tid said sl@aft fluid presstire means pistons and actuating said pist6ns, a liousing iii whicli said sli@ift is slidably molinted, bearin- 100 means for said h6tisincr iileans to rotate s@tid liousiny; and @i by-pas's veiit in said cylin11 ders, Iiiiiitiii(y the rpii,ai-d movemeiit of said pistons aiicl stistainin(y saict pistons in tl-ie raised positioli. 105 16. A concrete @ii)e iiiachine coinprising hydraulic cylindei-@, pistons in siid c3,lindei-s, a pacl@er sli,,tft, iiieaus coupling said pistons and said sliaft., fluid p@essure means a@tuat,ing said pistons, a housino- in ivhicli 110 said shaft is slidably lilotinted, bearing meaiis for said I housing, a palle aiid means c6upl top of said cylinders to limit the -Lipivtrd means for said liousin(y. mea,,is adapted and L I , movement of s,,tid pistons. arralnged to rotate said housing, and also to 60 11. A coiicrete pipe machine comprisiiag supply tlie fluid ui'ldet- pi-esstii,e, a by-ptss 125 hydraulic cyliiiders, pistons in s,,tid cylin- vent in said cylinders, limiting the Lipward ders, a pacli:er shaft, meaiis coupling said inovement of s,,tid pisto,-is and sustainiiig pistons aiid s,@tid, sliaft, fluid pressure means said pistons in tl-ie raised positio-n, a pallet actu@-Ltiiig said pistons, a vent adjacent the adapted to rest on a molcl, and n-ieails cou65 top of said cylinders to limit the upward pling said. pallet and, stid pist.ons to raise 130 jjlcr mectns to rot,,tte said ap@ed to rest on a iiiold, said pallet and said pistons to raiqe sai pa.ilet, in the rkised posi- 115 tion of s,,vid piston. l@. A concrete pipe iiiachine compi,isino, hydraulic, cyliiiclers, pistoi-is iii said cylinders, :,,i pacicer SIA',Lft, ineans cotipliiig said an ' d shaft, fluid pressiire me,,tns 120 "istons S"i 1_ @pistons, a liotising in -whicli qct,-iatil saicl S, -iiounted, bearin(r 'tic sh 'Ift is slilal)ly

said pallet iii the r,,tised posit,ion of said pistoils 18. A concrete pipe m,,icl-iine comprisinliydraulic cyli@nders, pistons in said cylii@- ders, a pacl@er sliaft, means coupling said pistons and said shaft, fltiid pressure, means actuatiii(y saicl pistons, a housing in whicli saicl shaft is sliclably mclinted bearino@ mean @s for s,,tid liousing, means to rotate said 10 liotising, a cup formed at the, upper ends of said cylinders, said cylinders having perforat.ions tlierein le@q,cli@g to said cup, and 6,t drain pipe leaclin_g from said cup. 19. A concrete pipo iiiachine coinprising 15 liydralilic cyliiiders, pistons in said cylinders, a pael(er sliaft, a ei-oss liead secured to said pistons, said sliaft beingjournelled and supported therein, fluid presstire means aettiating said pistojis, a housing in whicli said 20 shaft is slidably molinted, bearing me,,tns for sa.id housing; aiid means to rotate said housing. 20. A coneret-e pipe, machine compr,sing 1- i,.ydraulic cylinders, pistons in said cylinders, a packer sh,,tft, a cross liead see-Lired to 25 said pistons, stid shaft being journalled and slipp orted therein, fluid pressure rneans aetuati n- said pistons, a. housing in which said sliaft is slidably molinted, bearidg means for said holising; means to rotate said housing; 30 q@ pa,llet, aclapted to rest on a mold, and rods risin g f-rom said pallet, saia rods b6ing adap ted to be eligaged by said cross head in the raised position thereof to raise said pallet from the mold. 35 I n testimony wl,.ereof, we have hareunto set our haiids at Los Angeles, California, this 5th day of October' 1923. GEORGE CUSHING MARTIN. CHARLES M. CRONKHITE.

Patented Apr. 20 1926. 1,58,1,653 UNITED STATES PATENT OFFICE. GEORGE CUSHING XARTIN AND CL-IAP.LPS M. CRONKIIITE, OF LOS ANGELES, CALIFORNIA. HYDRAULIC CONCRETE--PIPE -BTACHINE. To all zvAogn z't n?,ay concern,, Be it li:j-ioiin that ive GEopGr, cusu.ING iNTARTiN and CHAPLE@S M. CRONIIT-TI'EEI, both citizens- of the I TTnited States, residilig it t) Los Ano-eles, in the county of Los Angeles ,,tnd State of California, htare inventec I t neav ,tnd -Lis ful II dratilic ConcretePipe Mie y Application filed October 11, 1923. Sen'al No. 668,022. the combination with a trowelling head, ot iteans whereby, wlien the, head reaches tl-ie top of its moveinent, it will reiila-ill so, elevated until released; and when released will 55 instantly drop to initial worli:ino- positibii. ,Lnd the invention is broa sic an,,l dlv ne@@-, b,,i piaiieer iin. this respect and tlso witl-L respect chine, of wliieh t-he folloiving is a, specifica- to the means whereby this is accoinplished. tion. We have discove,red that it is possible to 60 10 This invention relttes to tht),t cl,,tss of tecomplish this object in -,t@practic,,tl macliino. niachines in which a verticilly recipi-ocatiii,)- by providiiig hydra-tilic@ means i the fo n n rin revolviiig trowellino, head is oper,,ible by of a ram or plunger o,perable, by a hydratipower to trowel 'I, nioist concrete or aggrelie mediuin such as heavy oil driven by a gate of water,, hyqralilic ceiiient, sancl., pump, for raising a,nd su.pporting the 65 15 broken rock and the, like insicle L mold for trowelling head, and a by-pass for releasing the purpose of f o.rnaing a section of pipe. the:lifti ng inedium; an alitomitic by-pass In machines of this kincl heretofore coii- beiiag I)rovidecl to limit the up-t,hrlist of the strue,t ed the trowellin- heads a,re recipro- ram :Nvhen the packer liead has been lifted ,catecl while being revolved ancl the tronvel- above the moli, ,ind me,,tns to release the 70 20 ling is begun while the 1-iotd is at the bot- liquid IIld allow tl-te rtm ctnd the p@acker toin of the inolcl aiad tl-ie plastic, ceitient-i- he,,td to, descend rtpidly..' tious m,,iterial of wliieh tlle pipe is to be Another object of the, invention is to promacle is led into the top, of the n-iold froill vide a pipe inaking machiia-- whicli will be pallet or 1-topper and the trowelliiig lieacl perfectly Linder the col-itrol of tl-ie - oper,,itor, 75 1)5 is lifted and operated froiii bottoi-ii to to@1) aAd wl;ieh can be manufletured@ at lower of the inold and to a level above the, top of clost than pipe ina-king Tnachines o@f the the mold. packer bead-t@pe horetofore known. It is necessary at the Close of the ul,)- Another object of this ilivention is to strol@ e, that thei 1-iead shall i-eii-iain at a level provide an iinproved n-ia,chine in which the 80 30 above the top of the pipe, section con-iplete,(.1; lilting @ of the, paeker shaft and the packer I tati aiild the cycle of oper,,ttion in iiiakiiig a pipe head dtirii.-lo, its ro on a cl wh n ile it is section, i@ciudes; placiiig the i'llold oi-i ,i. tiirn operatin(v to n-lanufacture the pipe, is accointable, revolving t-,he turn table to bi,ino- tl-ir, plislied Wt tn even rate througliotit the, enn'lold into position to receive tlie, trowellin@T tire length of the pipe, and a pipe, of evell 85 3;5 p,,teker hea4 and the plastic iiiaterial, tlieii@ texture and great density throligl-iout is prolowering tli-e head into the. iiiolcl and to the duced. botton-i thereof, Teediiio- the m,,tterial to thil Other objects are simplicity 'and duran-iold and siiii-Liltaiieou@1-y therewith rotating bilit@. t,lie head @-ind elevating the saiiie frolii th(, @ This invention is broadly new, basic ancl 90 40 bottom to the top of the n-iolcl, iiieanwhile pioneer in various features, and particultrlv placino, an eni,pty mold on thp, table anl in that in. this @ipe iiiali:ing inacliine we htve then i7ota,tiiio,,'the table to. withclra@v tli-.@ p@ovided iii coinbin,,ttion with -,,t revolving a c k e r s l i i f t , t n d p a c k e r h e a d , a n i coll.iplet,ed pi and its niold froni under tlio liea.d, u p I I pallet. or hopper tlid to put tl-io ei-iipty iiiolct hydraulic means @foi- r,,tisino- and lowering 96 into position for n-iaking the e 4 liext ece of the sha-ft and 1-iead, t-liei-,eby o -eatly r dlicing p pipe. t he weio-l-it @nd greatly ilicreasing the o-LitAn object of tllis invention is to slioitell put of ill,-le M"tchine. tlie, timo requir6d for this eyele and tl-iis ive An ob'ect is to, avoid the necessity of indo by providing ineans for lowering the termediate meaiis, sucli as ropes, pulleys., 100 t,O hetd at Iiigli speed. ge@rs, serews or otl-ier meel-iaiiical n-ieans to An object of this invention is to procluce r,,uise and lower the packer sliaft and hea('[

1,581,653 and to make the operation of ra,isinff ,tnd lowe,ring such shaft and head more, @irect tha.n heretofore, possible. Other objects, advantaoes and features of invention may appear fr@m the ace ' "omp"n' ing drawings, the subjoined clet,,Lil des,,ril)- tion and tlie, appended claims. The, inveiition may be carried o-Lit in v,,tri10 O-Lis forms. The, ,Lccompanyiiig drawi.ngs illtistr,,it6 tllc' iilvention in tl-ie form at present deeiiied most satisf actory. Figure I is ,tn elevation of a hy(Iraulic cemep-t pipe in,,tchine constructed in accord15 @nce ",ith tl-i@is iiiiention. The pacl,,er liead is shown lowered in a iiiold to th@ iiiiti@il trowlelling level. Fig. 2 is a fraume.ntal pl,@in view Of- tlle machiiie shown i.n ri ig. 1. 20 Fio-. 3 is an,enlarged fragnieiiial view sho,vv@i7ng in front. elevation., some of the parts going to niake tip this iiiventioii. Full lines indic,,ite the position of parts vvhen tlle packer 1-iead is at the highest poilnt, al'id25 dotted Iiiies indicate the lo-\Yest positior, of sucli Ptrts. Fio, 4 is an enlarged fragiiiental section on line W4, Fig. 2. This view qliows t@he li@draulic cylinders witl-i the r,,tins hel-cl at 30 . iiit by tlie. presstire of oil their hi_gl-iest po Fig. 5 is an enlaro-ecl frao-iiiental ,txial section sho-wing in detail parts elilbr@iced by line xl, Fig. 4. 35 Fig. 6 is ,t bottoin view of the ivoocl blocks and claiiips holding the pacli:er shaft wl-iieh is sliown in section. The troivelliiig packer liead is of usu,,tl coiistruction comprising the cyliiadrical section. 1 aiicl the troivelling ariiis 2 carried hv 40 the pacl@er sliaft 3 that is su , pported by hydr,,tulic pistons or rams 4 that are operated by -,t hydraulic iile@dium 5 -%ihich ma@ be ,i heavy oil or other suitable pi-actically noncon-lpressible fluid, -vvithin tl-ie liVdrtLilic cyl45 inders 6 to wliieli the medi-LiiiLi 5 is delivered by a powerful liydraulic pump 7 drii,eii t@rough sprocli:et o-etring 8, 9, 10 leading from the main shift 11 that is colinected throligh gearing 26, 27 to revolve the paelcer 50 sliaft 3 and packer heacl 2, ,ind tl-i,,Lt is driven througli pulley 12 by po-wer from any -,,@uit,-@ble soiirce as an electric motor, not showp, to pump the, medium 5 froiii,a reservoir l@ forrniiig p,,trt of ,t IlyclraLilic circuit. Said 55 mp is connected by suction pipe 14: witli p@ said reservoir to draw liquid tlierefrom and is aclapted to force the medium 5 throligl-i I)ipes 15 to act ilpon the lo-",er ends of the 00 hydraulic cylin,clers 6 -whicli are vertically arranged on opposite sides cf the packer sl-iaft 3 that is carried by cross-licad 16 to -wliieli the pistons 4 are -fixed and witl-i whi-ch the sliaft 3 and the p,,teker heacl I move up as 65 the liq-Liid is puinpecl against the lower ends of said pistons. Tlae cyliiiders 6 are provided it their iipper ends ivitli veiits 17 that open iiito a cup 18 connectecl by a gtavity return pipe 19 witl-i the re@@.@ervoir 13. The return passage forired by the vents or perfcratioiis 17 and 70 tl-ie return pipe 19 is of sufficient capacity to relieve the hy(Traulic pressure on the pistons 4, alloiv the@ idistoiis to retch a state of eqtiilibriuiii, and ilius -cleteriiiine +,lie heights 75 to Nvhicli the pistoiis will be lifted and at ivliicli they ivill be lield by the hydr,,tulic presslire froiii the Plill'IP. 8talidards 20 ,tre. fixed to aiid exteiid up froiii the i.,,sucil pal'iet oi@ liopper 21, and are coiinected aL their upper ends by lost li'lo- 80 tion iiie@,@Lns to the yol@e 16 to be lifted thereby at the end of the -Lip-strol@@e of the pistoiis 4. so that ivhen the p,,tcli@er head is lifted ibov@ the level of the inolcl and of the completed lengtl-i of pipe, riot sliowi-i, tl-ie pallet 21 -\iill 85 be lifted aboi7e the level of the, 1-riold a so tli,,it the mold and the piem of pipe thereiii, not shown, iii,,ty be removed froin benetith tl-ie pallet by rotation of tl-ic turn table 22, go The hydr,,Luli@, illediiiiii 5 is piiinped. frolii the reservoir or suiii]) 13 by the p-Liiiip '(. thrcii(i-li the pipes 15 iilto the loi@ier elids of the eyiinders 6 thereby lifting the, i,,,tms uiitil they'pass ,t sti incient iiumber of the perforations to alloiv said iiiediiiin to eiit tlirougli 95 the perforatioiis 17 intc, the, cup 18 froi-ii ivhence it floiis tlii@otigh tlie, pipo, 19 back into the i-eservoir 13 to supply the ptiliip circuit. The raiiis are thus stipported in ele- 100 vated positioii to hold the yoke, 161, tlle pacli:ei- sliaft 3 und the p-,ueli:er head 1 above the level of the mold. The st,,tlidards 20 are vertically lilovablp tlirotigli giiides 23 and are provided witli 13 sboulders ivhich iiiiy be collars 23' -.Lclapted to rest on cert,.Iin o . f said ),ulde,-, when the pallet 21 engages tho top of the mold a. Said o-uides hold the pallet alined -\Vith the niold, and the ptllet is ,tdapted to eii(ra(ye, 110 the i-iaold and to liold the, lilold iii plice when the st-,tiiclards are ill theii- IoNvest position shoiin ill Fio-. 1, in -wliieh positioji sai([ standards rem@aiii at ,til tiii-ies except at the later portion 6f the up strol,:e of the pistons 4, aiid then the pacl@-er lie,,id is lifted above the coi-iipleted pi pe, and the p,,tl let or hoppei21 is also lifted so as to leave the mo d ree to b@,, reiiiovecl by i-otation of the tiirn table 22. By-pass and returii pipes 19' coiitr olled bv 1-00 b37-pass aiid returii valve 24- are.provided t"O revei-se the operation of the iiiachine iv, itliout iliterfering %),ith tl-ie coi-itii-ii-lous op-,ritiori of tl-,te ptimp. 125 The lever 25 Liiader conti,-ol of the oi)erator iiiay be m-,inip-Lilated to opeii the valie 24 to sucli -,tii exteilt @s to alloAA, the Meditim 5 froiii tl-ie punip I,hd also froiii the cylip-ders to returii to the reservoir or stimp 1"D. 130 Wlien the valves 24 are fully opened the

meiliuiii upholdmg tl-ie piston may retur-n so q-Liieldy that the pistons ai-e @@tually dropped ii-istantaiieously' thus lowbring the packer head to fl-ie initia 1 position shoavn iii Fi(,. 1, and also.,,tllo iiig tl-ie pall@t to engage w tl-i@top of tlle niold. Iii practical 1-ise the operator will start the puinp and close the valves 24 so that liquicl is puinped froll'i the sulllp to elevate 10 the pistons and paelkei, head to their highest position. A worki-iian will place the mold upoii the turn table and revolve the table to bring the inold u-iider the pallet to receive the pacli:er head, aiid tl-ien the operator will 1,5 open the, valve 24, th-Lis allo-,ving the packer liead to drop to iiiitial position. Then the @enaeiititiolis inaterial fron-i which the pipe is to be made will be introduced @into the n'lold tlirouoh the hopper or pallet and the 20 valves 24 will be closed to stich an extent as may produce a required ascent of the paclzer he@d whicli is coiistantly revolved in the usual way by means of the gear 26 lon sha.f't 11 inesl-iing witli gear 27 that is arraiiged te, 25 rotate the packer shaft 3. The rotary motion of the pacl@er head is obtained by means of the power shaft 11 throligh th'e bevel gear 26 into the bevel gear 27 throiigh which the square pacli:er shaft 30 3 passes, so that rotation of the pulley 12 rotates the shaft 11, gears 26, 27 and the pacli:er shaft 3. The liousilig 28 is a hollow casting with holes 29 for earess of dirt, sand and gr,,tvel zn 35 wlaich inay be carried up by the pacl@er shaft inside tlie liousing 28 ivliieh is suppo,rted aiid carried by upper and lower bearings 30 and 31. 32 sho-,vs Al@vooden bloclis bolted between 40 clai-nps 33 and 34 tl-lat eno-age sqtiare pacl@er sliaft 3 alid wliieh iiiay be adjusted by looseniiig the bolts b in plates 33 ,Lnd 34 to hold the shaft rigid during course of operation, alid as ,i result of wear which inay 45 occur either in the sliaft or blocl@s 32. There are four of the blocks 32 one on each side c,f the square shaft 3. The turn table 22 is pivoted at 35 and is provided with wlieels 36 to facilit,,tte its ror)o tation. 37 is a handle attached to the side of th turn table for conveiiieiitly rotating the same. Nuts 38 on standards 20 are the inetns for piel6iig up stanclards 20 wlien the yolie 16 55 reaches the top of its travel for the purpose Of raisiilg pallet or hopper 21 above the top of the mold a after the piece of pipe has been completed. The drawiilg sliows the valves 24 oper66 ated by two levers 25 which in turn are engaged by one rod 39 which, iii turn is oper,ited by',t lever 40 pivoted at 41, ancl provid d witl-i t handle 42 conveniently located at its free end; said lever and said rod being ,65 pivoted at their intersection 43. 43 44 is a bearing permanently attached to the top of shaft 3 the plirpose of which is to redtice frictiol'i betweeii the rotating pack6r shaft 3 ,tnd the supportinlr bearing 16 during operatioii. To It is tl-llis seen that by providing a p . ipe inachine h,,tving a paelcer sliaft with a hydraulic ram lifting iue,,ins for r,,Lising and lo-weriiag said pacl,:er shaft, we ha-ve rnade it possible to maxiinize the@ speed 0 opera.tioii, 75 and at the saine tinle have provided for continuo@us operation of the packer shaft and other parts witl-iout the necessity of aiiy reversing gears or inechanism and that by malking the driving niechanisin such as the 50 sh,,ift 11, aiid tl-ie oearing between tlle power shaft 11 ,tiid the, -shaft 3, operate iiidepeiidently of the lifting n4etns, the revolving of the paclzer 1-iead iiiay be coiitinuous at a predetermined s eed w hi.le tl-ie raising and low- 85 erina of tl-ie packer head can be effe6ted at wid@ly -@'arying rates of speed. By'providing tl-ie vents 17 ,tnd tl-ius voidino, the llydraiilic 1-iiediiim from the top of tIZ cylindiers, we have made it practical to 90 operate the pacli:er head in its tip and down movenient by the iiia,nipulation of the bypass valve witholit danger of breaking frcm over strain. . It is -Linderstood that the d-Liplicatio n of valve 24 aild pipe 19' is simply for l@5 conv eiii requ isit6 floiv. By c dra ulic lifting ram with a erat ed by the main driv e s the pacl@er head -",e have inade provisi r o,reat simplicity 100 of construction aiid i @p on in pipe rnachin es. By eniploying the hycl-raulie, means for raisiii@ aiid lowerido- the packer shaft aiid conttolliiig the same by the -valve, we bave made it po@sible to control the packer 105 head eit.her at the top or bottoiii of -tts travel or at tiiy point in between; alid by means of vent s 17 we 1-iave made it impossible to excessivel y lift the pacli:er head and the pallet; and by directly liftiiig the pacl@er shaft 110 carr ying the packer head, silnplicity aiid pow er are both secured with a light constiuction. W e