Патент USA US2406025код для вставки
Aug. 20, m'. H. L. MOOR PIPE FORMING MACHINE Filed May 51, 1943' 2 Sheets-Sheet 1 ` INVENTOR.' . #FQMA/v ¿_ Moo/Q. BY ‘ má , Au., w 1946. H. L. MÓOR - ¿406,25 PIP-E FORMING MACHINE Filed May 3l, 1945 ì 2 Sheetßs-Sheet 2 ` ' _.INVENTOR. #EQ/»MN L Moog. BY l l* _ l ~ Patented Aug. 20, 1946 ¿40ans UNITED STATES PATENT OFFICE PIPE FORMING MACHINE Herman L. Moor, Olive Township, St. Joseph County, Ind. Application May 31, 1943, Serial No. 489,109 21 Claims. l (Cl. .Z5-3.2) 2 , This invention relates to a pipe forming ma An larcuate longitudinal wall I5 concentricwith bottom I2 extends from a point intermediate the ends of the frame to the rear of the frame and merges with a »cylindrical portion I6 projecting ’ rearwardly from the frame. The outer diameter of portion I6 conforms -with the outer dia-meter of the pipe to be formed. A vertical chute or passage I1 projects upwardly from wall .I5 and communicates with a hopper I8 which is secured to and supported by the rear end of walls II at its upper end. chine. The primary object of the invention is to pro vide a machine for simultaneously making and laying in a trench a continuous and jointless pipe formed of concrete or other plastic material. A further object is to provide a machine of this character with means for incorporating reinforc ing material within a pipe as the same is formed. A further object is to provide a machine of this character for compacting backñll around a form in advance of the pipe-making and layingN operation, whereby said compacted backñll con stitutes the outer form for the pipe. Two or more cross bars I9 are secured to and extend transversely between the «walls» II adja A further object is to provide a machine of -' this character with means for vibrating the plastic thereon by any suitable mounting members 2|. Drive shaft 22 of the engine projects rearwardly material while the same passes from feed means to molding forms thereof. therefrom and is journaled at its end in a bearing 23 carried by a cross bar 24 extending transversely between and secured to the side walls I I. A pinion 25 is keyed to shaft 22 and meshes with a gear v25 therebelow keyed to a shaft 21. The shaft 21 is journaled in a bearing 28 sup ported by a cross bar 29 extending between and secured to sides II. A second lbearing 30 mount ed on a bracket arm 3I supported at the front end of wall I5 also journals shaft 21. A bevelled pinion 32 is mounted on the rear end of shaft 21 A further object is to provide a device of this character having an elongated ñexible inner form trailing therebehind to provide an interior sup port for the fresh-laid pipe during the period the same is setting to shape. A further object is to provide a machine of this character which is self-propelling. A further object is to provide a machine of this character with a rotating and vibrating cyl inder mounting a screw to feed plastic to and compact it in an annular mold cavity, said cylin der constituting part of an inner pipe mold. Other objects will be apparent from the draw cent the front thereof and an internal combus tion engine 20 or other drive means is mounted vand meshes with a bevel gear 33 keyed to a trans The ends of shaft 34 are mounted 30 verse. shaft 3d. ings, description and appended claims. In the drawings: Fig. 1 is a top plan view of the machine with parts shown in longitudinal transverse section ,. in openings formed in side walls I~.I and spanned .by plates 35 secured to the outer faces of said walls. Shaft 34 is journaled in bearings 36 sup ported by vertical bracket arms 31, Fig. 3, pro jecting upwardly from wall I5 and by longitudinal bracket arms 38 projecting forwardly from chute .I1. Adjacent .the opposite ends thereof, shaft `34 has circular .cams 39 mounted eccentrically thereon and -keyed thereto and encircled by rings taken on line I-I of Fig. 2. Fig. 2 is a longitudinal vertical sectional view taken on line 2-2 of Fig. 1. Fig. 3 is a vertical transverse sectional View taken on line 3-3 of Fig. 2. di) 45 mounted on the forward ends of a pair of bars Fig. 4 is a Vertical transverse sectional view 4I extending longitudinally at opposite sides of taken on line 4_4 of Fig. 1. chute -I1. Bars 4I mount _a transverse ramming Fig. 5 is a vertical transverse sectional view plate 42 at their rear ends and adjacent >and rear taken on line 5-5 of Fig. 2. wardly of the rear ends of side walls II. The Fig. 6 is a vertical transverse sectional View plate `42 is of a width slightly less than the width taken on line 6_6 0f Fig. 2. .of frame Ill, .and has a concave arcuate lower Fig. 7 is a side view of the vibrating inner cyl 4edge ,43 whose radius is slightly greater than the inder of the machine. radius of the outer. periphery of frame cylinder Referring to the drawings, which illustrate the I6 upon which the lower central portion of said preferred embodiment of the invention, the nu 50 plate 42 bears in spaced relation to the rear end meral II] designates the frame or body of the ma of said cylinder. y chine. Frame I0 is formed of rigid metal plate material and comprises vertical side walls II, an arcuate bottom I2, and an arcuate front I3, said bottom and 'front merging in a curved portion I4. A wideannular bearing 44 is mounted at the forward end of the annular space deñned by frame bottom I2 and wall I5, said bearing pref erably comprising Aan outer raceway -45 and an 2,406,025 3 inner raceway 46, each having two or more spaced 4 extends into the rearmost element 10 and ñxedly mounts a fitting 15 having a cup-shaped or an registering circumferential grooves receiving hard nular retainer 116 against which the rear end of metal bearing balls 41, and end retainer rings a tensioned coil spring 11 encircling said cable 48 suitably constructed to seal oil therein and exclude plastic. A cylinder 49 is journaled in Cil bears. A disc 18 having a small central aperture 'i9 nts within the rearmost element 10 and bears bearing 44 adjacent its front end. marginally against the internal shoulder between Cylinder 49 is best illustrated in Figs. 2 and '1, element 19 and reduced diameter collar 1| of said and its outer diameter is equal to the inner diam element. Spring 11 presses against >the outer eter of the pipe' to be formed. The cylinder is elongated to project rearwardly from >the cylinder' 10 outer face of disc 18, and cable 13 passes freely through aperture 19. Any selected number of I6 at 59 and to project forwardly of wall l5 at 5|. A helical external feed screw 52 is carried by the " .l elements 10 may be interconnected in this man central portion of cylinder 49, extending from bearing 44 to a ,point substantially coincident ' A vertical boom or mast 80 is ñxedly mounted with the rear end of frame cylinder I6. The 15 at the front of frame I0, said mast being sup ported in a socket 8l carried by the lower portion screw 52 is of a diameter less than the inner . of the front of said frame, and being positioned diameter of cylinder I6. Two or more spaced by retainers S2 above said socket. The upper longitudinal ribs 53 are secured within`cylinderv most retainer may include a hitch ring 83. Mast I6, said ribs being of a thickness to be engaged ‘ by screw 52 to form supports for the cylinder 20 89 preferably extends to a considerable height, and mounts brackets 84 «projecting laterally and oppositely therefrom adjacent its upper end. Each bracket 84 journals a pulley 85. A pair of opposite> laterally projecting brackets 86 is se sure plate 56 is removably mounted on the front end of cylinder 49 and has >a central bea-ring 51. 25 cured to mast 80 intermediate the height thereof. Each bracket 86 mounts a winch 81. A guy ca A disc 58 Ais fixedly mounted within the cylinder rearwardly >of bearing 44. -The rear end of cyl inderA 49 is provided with aclosure plate or spider 54 having Ya central aperture 55 therein. A clo intermediate the ends thereof and has a. central ble B8 is wound on each winch, extending up wardly around a pulley 85 and then extends lat bearing 59. A shaft 6,6 having a central bore 6I erally to an anchor spaced from the trench 89 therethrough is journaled in bearings 51 and 59, and projects» forwardly `from the cylinder. An 30 in which the machine operates. Mast 80 is pref erably of such height and the guy anchors are unbalanced arm 62 is ñxedly secured on shaft preferably so spaced from the trench that work 69 adjacent disc 58. A pair of abutment rings men and vehicles may pass thereunder without 63_‘are~secured to shaft 60 onropposite sides of interference. Whiletwo guys have been illus bearing 51 to prevent relative endwise movement of the shaftand cylinder. The portion of cylin 85 trated and may be adequate to support the ma chine in vertical position in the trench, four may be used if desired by providing the necessary num ber of pulleys and Winches therefor.4 A pulley 6_4 is mounted on engine shaft 22 for An.> elongated bent tube 90 having a vertical wardly of pinion 25, and a pulley 65 is mounted on the forwardly projecting end of shaft _60. A 40 portion secured to the` front of the frame at 9| and a rearwardly longitudinally extending lower `belt 66, preferably a V-belt, is trained around portion supported by a bracket 92 is mounted said pulleys to rotate shaft Vlill and unbalanced within the machine frame with its rear portion ann 62 at comparatively high speed, thereby terminating adjacent to and in axial alignment causing said shaft and the cylinder to vibrate. with shaft 60. Suitable means (not shown) may _The forward projecting end portion 5I of cyl feed reinforcing wire 93 (Fig. 5) into said tube inder >49 mounts an `annular sprocket 61, and a to be guided therethrough and into bore 6I of sprocket 68 is mounted on shaft 21 intermediate shaftI 60. A second bent tube 94 has its ends bearings _28 and 39. A chain 59 is trained around secured by an L-shaped bracket 95 ñxedly se said sprocketsto rotate cylinder 49. It will be cured within the cylinder 49 rearwardly of disc 50 noted that the cylinder 49 is rotated at a low 58, whereby one end thereof is axially aligned speed compared with the rate of rotation of shaft with bore 6l to guide wire 93 from the shaft 4lill, by virtue of the speed reduction effected bore to and through a hole 96 in the cylinder. through gears 25 and 26 and through sprockets As here illustrated, hole 96 extends through one 61 and 68. An elongated flexible inner pipe form trails be 55 of the convolutions of screw 52 at a point rear wardly of ribs 53 and adjacent the rear end of hind cylinder 49. As herey illustrated, this forni cylinder i6, whereby said wire is coiled as cylin is made up of a plurality of articulated annular der 49 is rotated. , , f non-collapsible sections or elements -10 each of One or more additional tubes or guides 91 'may the same outer diameter as portion 50 of cylin der 49. Each element 10 hasv a reduced diameter 60 be mounted within the frame at the front thereof, supported’by brackets, as brackets 9i and 92, for portion 1I projecting from the front end thereof passage of longitudinal reinforcing> rod stock and ñtting within the rear end of the preceding therethrough by any suitable means (not shown). element or of the cylinder 49 with a small clear Frame lll and wall I5 may have longitudinally ance» The rear edge of each element and the shoulder between the same and portionll at the 65 spaced openings 98 and 99 therein through which such rod stock may be'pas'sed. The rearmost ~front thereof, are preferably -:rounded or tapered openings will preferably be positioned in advance at 12. The construction and interñtting relation of the front ends of ribs 53, Sc‘that said rod may ‘of elements is such as to permit a limited amount der between disc 58 and closure plate 56 may contain cooling fluid, such as oil. ' of angular displacement of adjoining elements 10 pass therebetween to be guided longitudinally to'permit the same to follow a bend in a pipe. 70 The elements 19 are interconnected by a, cable 13 thereby. >passing therethrough. The front end of cable 13 extends through opening 55 in rear cylinder wall 54 and fixedly mounts a fitting 14 bearing against . , The operation of the device is as follows: The machine is lowered into trench 89 and may be pulled along therein immediately behind a trench digging machine by4 any suitable means (not .said cylinder __wal1. _The rear` end pf ¿cable 13 75 shown) which pulls a ’draw member .connected t0. 2,406,025 5 . the machine at 83, or the machine may be per ~ 6 time forsetting thereof, during which time theV mitted to propel itself as hereinafter described. mix must be confined within aform,VVV This is ac The guy cables 98 are connected to hold mast 89 cor'n'plishe'd` in the‘instant device by thetrailing and the machine frame in vertical position; the flexible' inner' form. The length of this form reinforcing wires 93 and the longitudinal rein 5 which is required will depend upon various fac-forcing rods are threaded or guided to proper tors, including the rate at which the machine ad feeding position in the machine; and hopper I8 is vances, the setting properties of the mix, i, e., the filled with the concrete or other mix; and the percentage of water contained in a concrete mix, machine is ready for operation. Best results are etc., .and the quantity of reinforcing metal em obtained by using a concrete mix containing a ployed. Thus the length of the trailing form minimum amount of water, and the mix may also used with concrete pipe may vary from a mini be treated to impart quick-setting properties mum of forty or fifty feet to two hundred feet thereto. i or more. Note that the rotation of cylinder 49 by Upon operation of the engine 20, three opera which the trailing form is drawn may impart a tions occur, apart from the feed of the rein limited rotation to at least some of the elements forcing wire and rods, namely, reciprocation of of the trailing form, and such rotation in con ram arms 4I and ram plate 42 by cams 39, rota junction with the forward movement of the trail tion of cylinder 49 by chain 69, and rotation of ing form serves to smooth and finish the mix at shaft 99 and unbalanced arm by belt 65. Back the interior of the pipe as the mix is setting up, fill Iûû is continuously emptied into the trench 20 thus forming a smooth solid inner peripheral pipe 89, and is compacted by the ram plate 42 whose surface which is a distinct advantage. stroke terminates forwardly of the rear end of It will be apparent that the guy cables must frame cylinder I6. Hence cylinder I9 constitutes be advanced from time to time as the machine an outer form around which the backñll is com advances, and this renders the provision of four pacted, so that the machine forms a circular earth such cables, together with automatically adjust tunnel therebehind. Also, it will be apparent that able Winches 81, an advantage inasmuch as the if the backfill material is emptied into the trench operation of the machine may then be continuous continuously, the action of the reciprocating ram since the machine would not then have to, be plate 42 pressing thereagainst will serve to prop-e1 stopped for guy cable manipulation. It will be the machine forwardly in the trench at a rate - understood, however, that guy cables have been proportional to the rate at .which the backiill ma shown and described as illustrative only of one terial is fed. rI‘his action assumes, of course, that convenient means for positioning the machine, the backñll material is of a consistency to permit and that other positioningmeans may be utilized compactingl thereof, since it will be apparent that if desired. the backñll must be finely compacted to form an From the above it will be apparent that the abutment against which the pushing action may machine possesses -the following distinct advan be exertedand also to maintain its shape after tages, among others: automatic operation; man the frame cylinder passes therefrom. The rotation of cylinder 49 serves to rotate screw 52 to feed the plastic mix rearwardly for ual labor or attendance is held at a low point; inder 49 is rotated, the mixis compacted in the annular receiving cavity therefor to insure uni formity and solidity of the pipe IUI being formed. fllled pipe as compared to the cost of a conven the machine is capable of self-propulsion; all attendants work at ground level; a strong com continuous discharge into the annular cavity be pact jointless pipe is produced; the pipe is tween the inner form and the circular cavity in formed in the position at which it is to remain the compacted backñll behind the cylinder I6. in use, thereby minimizing the problem of stresses By properly correlating the rate of forward move incident to settling of surrounding earth; and ment of the machine with the rate at which cyl 45 the speed and low cost of the finished, back Rotation of the cylinder 49 also serves to wind reinforcing wire 93 into helical form concentric with and properly positioned in the pipe wall in termediate the inner andr outer peripheries there of. The cylinder is vibrated by the comparatively tional pipe line which includes the multiple factors of manufacturing cost, transportation, handling, joining and back-filling, etc. i Another >feature of the machine is that it is not adversely affected if small quantities of water are present in the trench, since the mix is fed into the receiving cavity therefor between the inner form and the compacted contoured earth back-fill under pressure sufiicient to force the water ahead of the rear end of frame cylinder I6, and thus prevent adverse effect thereof upon high speed rotation of shaft 69 and unbalanced arm 62 therein, and thus the plastic mix is vi brated as it is kpropelled in the cylinder I6 by screw 52. This also assists in the compacting and the newly poured mix. solidifying of the mix. Note that the journaling of the cylinder 49 at its forward end.- only pro 1. A machine kfor forming a pipe in a trench, vides a cylinder mounting facilitating vibration. 60 comprising a frame adapted for movement Ain At the same time, the provision of the longitu said trench and having a lower cylindrical por dinal ribs 53 in the frame forms a 'support for the tion, a reduced diameter cylindrical rotatable free or unjournaled end of the cylinder to limit member concentric with said frame cylinder and the extent or amplitude of the vibrations and to cooperating therewith to deiine an annular limit the stresses applied to bearing 44 by the chamber, and means for feeding plastic material vibration. The high speed rotation of shaft 6l] to and rearwardly through said chamberv into and the incident vibration generates heat, and said trench, said cylindrical member including consequently the filling of the forward end of the an elongated portion formed `of relatively rotat cylinder with a liquid, such as oil, serves as a heat transfer means to hold the heat at'bearing able articulated sections normally in frictional end engagement adjacent their circumference projecting rearwardly from said frame to con transmit the heat to the cylinder walls to heat the tinuously interiorly support said mix While the latter sets in said trench. A concrete mix requires a certain minimum 75 2. Afmachine for forming a pipe in laïtrench, surfaces, etc., within safe limits and to uniformly mix. f ° 2,406,025 7 8 . comprising a frame having a rearwardly project ing tubular portion, a rotatable inner form with in said tubular portion defining a tubular cham ber, meansfor rotating said form, an external feed screw on'said inner form, plastic feed means communicating-with said chamber, and a longi comprising a frame adapted to be advanced in said trench and having a lower longitudinal pas sage, an inner form’rotatable within-said'pas sage and cooperating therewith to denne a tubu lar chamber, -means for feeding plastic material to and rearwardly through said chamber into said trench, and an elongated‘non-collapsible flexible tudinally shiftable ram for packing earth around . said tubularl frame portion. trailing member in torque transmitting end en 8. A machine for forming a pipe in atrench, gagement with said rotatable form and project ing rearwardly from said frame to interiorly sup 10 comprising a frame having a rearwardly project ing tubular portion, aninner form in said tubular port-said mixrwhile the same sets in said trench, portionV cooperating therewith to define a tubular said trailing member> including a plurality of chamber, means for feeding plastic material to articulated> relatively rotatable, cylindrical por;-v and rearwardly' through-said chamber, a trans tions in torque transmitting end'engagement. k3. A machine for forming a pipe in a trench, 15 verse substantially vertical ram, and> means for longitudinally reciprocating said ram to pack comprising a frame adaptedto be advanced .in earth around said tubular frame portion and said trench and having a lower longitudinal pas thereby advance said frame. ì ' sage, an inner form rotatable< within said-pas »9. A machine for forming a pipe in a trench, sage and cooperating therewith to define a tubu lar chamber, means for feeding plastic material 20 comprising a frame having a rearwardly project ing tubular portion, an inner form in said tubular to and rearwardly through said chamber into portion cooperating therewith to deñne a tubular said trench, and an elongated flexible trailing chamber and including a portion projecting rear form of substantially uniform cross .section in wardly from said frame, Ya transverse substan cluding a plurality of relatively rotatable articu lated rigid units connected to and in rotation 25 tially Vertical ram plate, a transverse cam shaft journaled in said frame, means for rotating said transmitting engagement with the rear end of shaft, longitudinal bars so arranged as to be said inner form. > Y shifted by said shaft and connected to said ram 4. A machine for forming a pipe in a trench, plate, said ram plate reciprocating longitudinally comprising a frame adapted to be advanced in said trench, and having a lower longitudinal 30 on said tubular frame portion to compact back i‘ill therearound, and means for feeding plastic passage, an' inner form within said passage and material through said chamber and compacting it cooperating therewith to deñne a tubular cham around said inner form rearwardly of said frame. ber, means for feeding plastic material to and l0. In a machine for forming a pipe in a trench, rearwardly through said chamber into said trench, and an elongated flexible trailing form 35 a frame, a hopper carried by said frame, a longi tudinal tubular portion at the bottom of said of substantially uniform cross section in fric frame projecting rearwardly therefrom and com tional end abutment withV said inner form and municating with said hopper, a substantially including a plurality of similar rigid tubular vertical transverse ram plate bearing on said units each having a reduced portion fitting in frictional torquetransmitting relation to an ad 40 tubular portion rearwardly of said hopper, means carried by said frame for longitudinally recipro jacent unit and an elongated flexible draft mem-_ cating said ram plate to compact backñll de ber passing through said units with its opposite posited around said tubular portion, said plate ends connected to said inner form and to said rearmost unit. . " ' ’ and means advancing said frame as backfill is ' deposited therebehind, and an inner pipe form in 5. A machine for forming a pipe in a trench, comprising a frame adapted to be advanced in said trench and having a lower longitudinal pas sage, a cylindrical form _journaled in said pas sage and cooperating therewith to deñne a tubu Asaid tubular portion and projecting rearwardly therefrom for shaping >the interior of a pipe formed from material discharged from said hopper. 1l. A machine for forming a pipe in a trench lar chamber, a feed screw in said chamber car- . comprising a «frame’adapted to be advanced in said trench, an outer form carried by the bottom of said frame, a cylindrical inner form rotatably mounted within said outer form to denne a tubu ried by said form, means for rotating said form, means for feeding plastic material intov said chamberv for discharge'intofsaid trench ‘by said screw, and an elongated, ñeXible'non-collapsible larchamber therein, a'helical feed member ñxed form in frictional end engagement with and . to and encircling a portion Yof said inner form, means for feeding plastic> material to said cham ber, a shaft iournaled longitudinally in said inner drawn> by said first form to continuously inte riorly support said plastic material in said‘trench as it sets said last named form including-a plu rality of relatively rotatable cylindrical sections in frictional torque transmitting end to end en gagement. - " ` ' ' / form, an unbalanced weight carried by said shaft 60 within said form, means for rotating said inner form, and means for rotating said shaft and , weight at higher speed than the speed of rotation >6. A machine for formi-ngrapiperinra trench; comprising a frame adapted " for of said inner form to vibrate said inner form12, A machine for forming a pipe in a trench, movement through said trench‘and' having> 'a lrearwardly projecting tubular portion, an inner form within said tubular portion' deñning'a tubular chamber in said frame, said inner form including a uni - comprising a frame having an outer form iixedly carried by and projecting rearwardly from the lower portion of said frame, a transverse sub stantiallyY vertical lram plate above said outer form, means for longitudinally reciprocating said ram plate'to compact backflll around said outer form rearwardly trailing ` portion, a ram re ciprocable longitudinally of said frame for pack lng earth around said tubularframe portion, and form, an inner form mounted within said outer form to denne a tubular chamber therein, means means for feeding plastic material to and through said chamber for discharge between said trailing for feeding plastic material to and through said chamber, and means for vibrating said inner form portion and said packed earth rearwardly of said frame. ' ‘7. A machine for forming - ' ‘ ' pipe'in `alt-trench, 75 form. ~ . y Y 2,406,025 10 13. A machine for forming a pipe in a trench, form a tubular chamber, means for rotating said form, an articulated cylindrical form trailing and comprising a frame having an outer form ñXedly carried by and projecting rearwardly from the lower portion of said frame, longitudinally re ciprocable ram means for compacting backñll around said outer form, an inner form journaled within said outer form to define a tubular cham ber therein, a feed screw ñxed to and encircling said inner form, means for supplying plastic material to said chamber, means for rotating said inner form, and means for vibrating said inner providing a continuation of said cylindrical form, means reciprocating substantially horizontally for compacting earth around said rearwardly pro io brating said rotatable form. 18. A machine for forming pipe in a trench, comprising a frame adapted to traverse a trench and having an elongated longitudinal passage deiined in part by a tubular portion projecting form. 14. A machine for forming a pipe in a trench, comprising a frame having an outer form ñxedly carried by and projecting rearwardly from the lower portion of said frame, longitudinally recip rearwardly from the lower portion of said frame, rocable ram means for compacting backñll around said outer form, an inner form journaled within said outer form to define a tubular chamber therein, a feed screw ñxed to :and encircling said 20 inner form, means for supplying plastic material to said chamber, means for rotating said inner form, and means for vibrating said inner form, said inner form including an elongated flexible, non-collapsible portion projecting rearwardly of said outer form. 15. A machine for forming pipe in a trench, comprising a frame adapted to be advanced in jecting frame portion as said frame advances, a feed screw in said chamber carried by said ro tatable form, means for feeding plastic material to said chamber, and means for transversely vi means reciprocating substantially horizontally for compacting earth around said passage as said frame advances, means for feeding plastic ma terial to and rearwardly through said passage, an inner pipe form within said passage and in cluding a uniform portion projecting rearwardly from said passage, said plastic material being discharged and shaped between said inner forms and said compacted earth rearwardly of said frame. 19. A machine for forming a pipe in a trench, comprising a frame adapted to traverse said trench and having a rearwardly projecting form said trench and having an outer form in the lower at the lower portion thereof, longitudinally recip portion thereof, an inner form rotatable in and 30 rocable means for compacting backfìlled earth projecting from said outer form and cooperating around said form, an inner form within said outer therewith to define a tubular chamber, means for form and projecting rearwardly therefrom, means feeding plastic material to and rearwardly for discharging plastic material around said in through said chamber, said inner form having an ner form rearwardly of said frame, and means opening therein intermediate the length thereof, means for feeding a flexible reinforcing member to and through said opening including an open ended passage extending axially of said inner form and curved at one end for registration with said opening, and means for rotating said inner` form. 16. A machine for forming pipe in a trench, comprising a frame adapted to be advanced in said trench and having an outer form fixed in the lower portion thereof, a tubular inner form journaled at its forward end portion within said outer form and cooperating therewith to deñne a tubular chamber, means for feeding plastic ma terial to :andrearwardly through said chamber, a longitudinal open ended hollow shaft journaled in said inner form, an unbalanced weight fixed on said shaft, said inner form having an opening therein rearwardly of said shaft, means for feed ing a flexible reinforcing member through said hollow shaft and thence laterally through said opening, means for rotating said inner form, and means for rotating said shaft. , 17. A machine for forming a pipe in a trench, comprising a frame adapted to traverse said trench and having a longitudinal passage at its bottom deûned in part by a rearwardly project ing tubular portion, a rotatable cylindrical form within said passage and cooperating therewith to for maintaining said frame upright in said trench. 20. A machine for forming a pipe in a trench, comprising a frame adapted to traverse said trench and having a rearwardly projecting form at the lower portion thereof, longitudinally recip rocable means for compacting backñlled earth around said form, an inner form within said outer form and projecting rearwardly therefrom, means for discharging plastic material around said in ner form rearwardly of said frame, a vertical mast ' carried by said frame, and guy cables carried by said mast and anchored at points spaced from said trench for maintaining said frame and mast upright as said frame advances. 21. A machine for forming pipe in a trench, comprising a frame having an outer form in the lower portion thereof, an inner form rotatable in and projecting from said outer form and coop erating therewith to define a tubular chamber, means for feeding plastic material to and rear wardly through said chamber, means for feed ing a reinforcing member into said chamber in cluding a passage extending axially of said inner form with its forward end open to receive said member and terminating in a lateral portion opening through said inner form, and means for rotating said inner form. HERMAN L. MOOR.