US2942590A - Pile puller - Google Patents

Description

E. DORNFELD June 28, 1960 PILE FULLER 2 Sheets-Sheet 1 Filed July 28, 1959 June 28, 1960 Filed July 28, 1959 E. DORNFELD 2,942,590

PILE FULLER I 2 .Sheets Sheet 2 IN V EN TOR.

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United States PatentO "ice PILE PULLER Eberhard Dornfeld, Esslingen (Neckar), Germany, as-

signor toDelmag Maschinenfabrik Reinhold Dornfeld, Esslingen (Neckar), Germany The present invention relates to a pile puller having a pull rod adapted to be suspended on the upper end thereof and adapted to be connected to a lower end thereof to a pile during the pulling of the latter. The pile puller further includes an impact member fixed to the pull rod adjacent the upper end thereof and a ram be- @Rliftented June 28, 190

by means of a combustion enginesystemand' the above described disadvantages are avoided.

It is an additional object of the present inventionvto provide pile, puller of the type .described'in .which' -the.

' forces acting in downward direction on the pull rod are neath the impact member carried by the rod for moving 1 upwardly along the rodto an impact position where the ram strikes against the impact member and downwardly along the rod to a lower end position.

Pile pullers of thetype described are usually suspended on a hoist and the pulling force of the hoist is augmented by the impact force of the ram on the impact member. In such pile pullers the ram may be driven by compressed air, by steam, or by an internal combustion engine.

'The presentj invention relates to aipilepuller in which theram is,reciprocated by'piston and cylinder means in form of aninternal combustion engine, 2

, Inknownjpile pullers of the type described, the reciprocating ram is usually made inthe fo'rm'of a piston or cylinder slidingly arranged, on the pull, rod forreciprocation thereon. In 'such constructions, the forceexerted by therarn in itslower'end position-has to be taken up the hoist and in such, constructions it is therefore preferable when theupressuregacting .on the ram the lower. endyposition'thereof is ;heldto a minimum. Com- 7 piston means; eachin the forrn ofjaqcdmbustion ejngi pressed ,airfor steam can thereforebe advantageously 5 used ina; construction in which the ram is formed as, a

piston or cylinder and in which the pressure of the driv-' ing medium, that is, the compressed air or the steam,

acts directly on the ram, sincesteam and compressed air pile pullers can work with a substantially constant presthe hoist supporting the pull. rodis; subjected to con- 7 siderable downwardly directed reaction forces. l Q As mentioned before,fit is common practice to; arrange the working cylinder for ,the pile puller coaxiallywith the axis of the, pull rod; Whendieselengin'es are-used for driving the, ram, in. such an arrangement, the necessary proper sealing of the pullrod on the opposite ends of the working cylindercauses also considerable difficulties. In

such an arrangement, further difficulties are encountered v to form the annular compression space in .such a way that perfect and complete combustion of the injected fuel will Occur, In addition, the proper cooling and flushing of a cylinder of annular cross section causes considerable difiiculties. 1 i r a It is one object of the present invention to provide for with respect to the axis of the pull rod.

greatly reduced. p Y p Itis a further object of the presentinvention; to prof-j. vide for an arrangement in which the drive, engine is'sub; stantially shock-free mounted on thepull rod er, the arrangement. I t

It is yet an additional objectof the present-invention to provide for an arrangement in which the'cylinders of the combustion engine driving the'ram re properly flushed and cooled. I

With the above objects iiiview, the present. invention mainly consists of apile puller including a pull rod ,hav ing a lower end adapted to be connectedto apileduring pulling of the latter, an impact member fixed to the pull rod above the lower end thereof, anda ram beneath the impact member carried by the rod for movement upwardly along the rod' to an impact position where the ram strikes against the impact member anddownwardly along the rod to a lower end position. The pile puller of the present invention further includes means cooperating. with the ram for reciprocating the same between the positions thereof and for converting the downward-force of the ram in the lower end position therebf into laterally directed force components directed substantially radially Preferably theram is driven by a paiiiof "cylinder and having each afcylindercarried' b 'th'fe pul allyfspaced therefrein,withthejaxis Q the y n e clinc'd' to the axis of the rod so thatthe end i the i den nearer to the ocl is at 'alhig h'er ammo um other end thereof, and 'a' piston reciprocablef in'jthe 'yl der. {The pistons of the pairpf cylinder and pisto t are respectively connected tothe ramby :a pair of fleeting ro ch r vot l yic nne'cted tit bl p i i thereof to the respective pistonlandfthe'ram. Thj X rangernent is 'madefin such a. wayflthat 'the' comic ng rods extend substantially parallel to. thef'pull rod when the ram is in the impact positionthereof'and extendilat}. erally from the pull rod when the ram is in the IovVerferid' =1 position thereof 'sothat in the latter positien, the downward force of the ram is'converted by the connecting into laterally directed force components. In' this way,

the forces acting in downward direction'on the, pull rod during the reciprocation of the ram thereon are g lfiatl'y reduced. f 7 Y In the preferred form, the drive engines for ram are not directly mountedon the pull jrod, but cart ed by a housing coaxially arranged with lthe pull rod mounted thereon, Preferably, elastic means are posed between the pull rod andtlie housing so I v V to which thepull rod is 'subjected, are Inottra in d i to the hou sing and to the drive engines mounted the "i1.

t In preferredform', the ramfisj formedfas' an annular piston coaxially arranged" on th ef pull' rod'and -the upper end of thehousing surroundsfthe ram to fomi therewith fa compression chamber in which air is compres during, the upward movement of the'raiinand icon ult means are 7 provided for feeding the, thus compressediair intothc cylinders of the combustion engines for properly cooling the same and for fiusliin g the interior of the; cylinders.

The novel features which; are considered as characteristic for the invention: are set forth in particular in the appended claims. The inventionitself, however, both as V i to its construction and its method of operation;together I i I 2,942,590

. a 3 with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Pig. 1 is a longitudinal section through the. pile puller of the present invention andshowing the ram in the lower end position thereof; and

Fig. 2 is a sectional view similar to Fig. 1 and showing the ram in its upper impact position.

Referring now to the drawing, it willbe seen that the pile puller according to the present invention comprises a pull rod 2 which is adapted to be suspended at the upper end thereof on a hoist, not shown in the drawing. The cable'of the hoist maybe wound about a pin carried in a pair of aligned holes formed in two arms extending upwardly from the upper end of the pull rod 2. The lower end of the pull rod 2 carries a pulling clamp 11 of any known construction, adapted to be clamped about the upper end of a pile to be pulled; An impact member 10 is fixedly mounted adjacent the upper end of the pull rod 2. Preferably, the upper end of the pull rod 2 is tapered as shown in the drawing, and the impact member 10 is formed with a correspondingly tapered hole arranged coaxially with the axis of the pull rod so that the impact member 10 cannot be loosened by upwardly directed strokes thereon. A ram 1 is carried by the pull rod 2 beneath the impact member 10 for moving up wardly along the rod to an impact position, shown in Fig. 2, where the ram'l strikes against the impact member 10 and downwardly along the rod to a lower end position, shown in Fig. 1. In the preferred embodiment shown in the drawing, the ram has the form of an annular piston coaxially arranged with the pull rod 2.

The ram 1 is reciprocated between the lower end position, as shown in Fig. 1, and the upperimpact position, as shown in Fig. 2, by means of a pair of cylinder and piston means in'form of combustion engines, Each of the cylinder and piston means comprises a cylinder 50 and a piston'l3 reciprocably arranged in the cylinder 5c.

' Inithe preferred form shownin the drawing, the cylinders 50' areformed integral with a housing 5. The housing 5 is preferably" arranged coaxially with the axis A of the pull rod 2, and a pair of elastic means 9, shown in the drawing as rubber rings,'are respectively interposed between the upper end of the housings and a flange extending in radial direction from the impact member 10, and between the lower end of the housing and the upper annular surface of the pulling clamp 11 fixedly mounted to the lower end of the pull rod 2. The housing and the cylinders 50 mounted thereon are thus carried by the pull rod 2 in ashock-reducing manner. This is especially important since the lower part of the housing carries also a .fuel container 5a, and shock-sensitive elements for the combustion engine such as the injection pumps 6, fuel condiuts 7 and injection nozzles 8.

The cylinders 5c are arranged laterally spaced from the pull rod 2 on opposite sides of the pull rod and symmetrically with respect to the axis thereof. The axes B of the cylinders 50 are upwardly inclined with respect to the axis A of the pull rod 2 so that the ends of the cylinders 50 nearer to thepull rod are at a higher elevation than'the otherends'thereof.

Each of the pistons 3 is connected with the ram 1 by a connecting rod 4, pivotally connected at opposite ends thereof to the respective piston and to thelram as best shown in Fig. 2.

The'arra'ngementis made in such a way that the connecting rods 4 extend substantially parallel to the pull 'rod '2 when the 'ram 1 is in theJi'mpact position as shown 'in Fig. 2, whereas the connecting rods 4 extend in direction of the 'axes B of the cylinders 50 laterally from the pull rod when theram lis in the lower end position as shown in Fig. 1. When the two pistons 3 are in their outer dead-center position, as shown in Fig. l, in which 'the combustion occurs, the two connecting rods 4 are only slightly upwardly inclined. In this position, the horizontal components of the explosion force acting on the two pistons 3 will compensate each other, whereas the vertical component of these forces are relatively small. When the two pistons 3 move toward their inner deadcenter position in which the pressure in the cylinders 5c decreases, the inclination of the connecting rods 4 changes to a. position substantially parallel to the axis of the connecting rod so that with decreasing pressure in the cylinders, the vertical force components transmitted to the ram by the connecting rods increases, whereby the ram is driven with a hard impact against the impact member 10. On the other hand, during the downward movement of the ram, the downward directed inertia forces are translated by the connecting rods into substantially laterally directed forces so that only a very small downward directed force will act on the pull rod 2. The arrangement according to the present invention will therefore produce only small downwardly directed reactions forces, and a hoist or crane of relatively light construction may therefore be used for the suspension of the pile puller of the present invention.

Another advantage of the arrangement of the present invention is that the cylinders and pistons of the drive engines are located laterally from the pull rod so that the combustion space of the engine may be formed in such a way so as to provide for the best combustion. In addition, the sealing problems inherent with the known constructions are completely avoided with the arrange ment of the present invention.

The arrangement of the present invention, preferably provides also for means to properly flush the combustion cylinders 50. To accomplish this result, the ram 1 is formed as an annular ring piston coaxially arranged on the pull rod 2 and the upper end portion of the housing 5 is in the form of a cylinder surrounding the annular ram 1. The upper end of the cylindrical housing is closed by the impact member 10 as clearly shown in the drawing, so-that the upper endportion of the housing, forms with the impact member 10 and the ram 1' a compression chamber in which air is compressed during the upward movement of the ram. i

The air thus compressed during the upward movement of the ram 1 is guided" through channels 5b formed through the wall of the housing 5 adjacent the upper end thereof and a jacket member 12 surrounding the housing 5 and substantially fluid-tightly connected at opposite ends thereof thereto through flushing slots 3b into the interior of the cylinders So, so that the cylinders are flushed with a great surplus of flushing air producing thus also a very efficient cooling of the cylinders. In the arrangement, it is not necessary that the annular ram piston 1 is sealed against the pull rod 2 or the cylindrical portion of the housing 5 since the arrangement provides for a great surplus of air, so that air losses due to leakage will not detrimentally affect the proper cooling and flushing of the cylinders.

The apparatus just described will operate as follows:

Before starting the apparatus, the ram 1 is preferably held by a conventional holding mechanism, not illustrated in the drawing, in a rest position, as shown in Fig. 2, in which the upper end of the ram 1 engages 'the bottom surface of the impact member '10. If the ram is now "released from this rest position, the working pistons 3 are moved by the connecting rods 4 from-their inner dead-center position, as shown in Fig. 2, towards the outer dead-center position, as shown in Fig. 1, whereby the air contained in the cylinders t 5c is compressed. When the drive engines are in the form of diesel engines. the arrangement is made in such a manner that the bottom surface of the ram 1 will engage the injection pumps 6 shortly before the/pistons 3 reach their outer deadcenter position, so as to inject in a known manner fuel from the fuel container 5a through the fuel conduits 7 and the injection nozzles 8 into the working cylinders QZfiflii a pile puller, in combination, a

5c where the thus injected fuel is combusted so that the pistons '3 are driven inwardly to drive the ram and this compressed air enters the'cylinders 5c through,

the slots 312 provided therein after the pistons 3 have moved inwardly suflicient to open the slots 3b. In its fixed to said pull rodadjacent said upper end thereof; a

ram beneath said impact member carried by said rod for moving upwardly along said rod to an impact position where said ram strikes against the impact member and downwardly along said rod to a lower end positiomcylinder and piston means in form of a combustion engine upper impact position, the ram 1 hits the impact member 10 and it produces thereby through the pull rod 2 and the pull clamp 11 an upwardly directed jolt on the pile to be pulled to loosen the same and to drive the same in upward direction. During the downward movement of the ram 1, however, substantially no downward .directed forces are exerted on the pull rod 2, since the downwardly directed forces of the ram 1 are translated by the connecting rods into latenally directed force components in the lower end position of the ram. tYItTwill be understoodthat each of the elements described above, or two or more together, may also find a useful application in other types of pile pullers differing fromi'the types described above.

- While the invention has been illustratedand described as embodied in a pile puller in which the ram is driven by combustion engines, itis not intended to be limited to the details shown, since various modifications and structural'chang'es. may be made without departing in any .way from the spirit of the present invention.

Without further analysis, the foregoingwill so .fullyfreveal; th :gistfof the present invention that, others can- -by applying current knowledge readily adapt .it for variousap and having'a cylinder carried by said pull rod laterally spaced therefrom with the axis of the cylinder inclined to the axis of the rod so that the end of the cylinder nearer to said rod is at higher elevation than the other end thereof, and a piston reciprocable in said cylinder; and a connecting rod pivotably connected at opposite ends thereof to said piston and said ram, respectively, said connecting rod'extending substantially parallel to said pull rod when said ram is in said impact position thereof and extending laterally from said pull rod when said ram is in said lower" end position thereof so that in said latter position the downward force of said ram is converted by said connect ing rod into laterally directed force components, whereby the forces acting in downward'direction on said pull rod are greatly reduced.

4. A pile puller comprising, in combination, a pull rod having an upper end and being adapted to be suspended thereon and a'lower end adapted to be connected to a pile during the pulling of the latter; an impact member fixed to said pull rod adjacent said upper end thereof; a ram b eneathsaid ampact member carried by said rod for moving upwardly along said rod to an impact positi'on where said ram strikes against the impact member and downwardly along said rod-to a lower end position; a pair of cylinder and :piston means beingeach in form'of a combustion engine and havingea'ch a-cylindercarri'ed' by ,plications without omitting features that, from, the standpointTpfprior art, fairly constitute essential; characteras a oflthe, ener o p c fic. asp t f; is n ention n ther efpreg-snch' adaptations should-find'areintended $9,;; b ;.-Q. nnr snd wi in x isanins n e. o squ a l as qfthsfl ow nsi a m What is claimed as new ,anddesrred to be secured-by .l etters lfatentis: a"- r i I. In a pile puller, in c ombinationfa pull rod havinga :lowerend adaptedtobe connected to a pile during pulling of the latter, aninipact member fixed to'said' pull-rod above said lowerv end thereof; a ram beneath saidirnpact member carried by said rod for movement upwardly, along said rod to an impact position where said ram strikes againstfsaid impact member and downwardly along said' ro'd toga lower-end position; and means cooperating with saidfrajm for reciprocating the'same between said positions there'o' and for converting the downward force'ofsaid L id lowerendp'osition thereof intoilaterallydirested orce components 1 directed :substanti'ally; radially lwith r p ctto theaxispf said pull rod.

s Q a lower end adapted to be connected to apile'fduringfpulling ofthe latter;' an" impact member 'iixedtosaid" pull q -for moving upwardly along saidrod toan impact position rod .a-b'ove saidlower. end thereof; a ram beneath said jimpact member carried by .said rod for movement upwardly along-said rod to an impact position where said strikes against said impact member and downwardly along said rod to atlower end position; a driving rod pivotably connected to said rain for reciprocating thelatter, said' driving rod extending substantially parallel to said pull rpdwhen said ram is in said impact position thereof and extending laterally; from said pull rod ,whensaid rain isflin said; lower end position thereof so that in the latter position'the downward force of theramis converted by said driving rod into laterally directe d components of force; and means cooperating with said driving rod for reciprocating the latter and said ram therewith.

, A pile puller comprising, in combination, a pull rod having an upper end and being adapted to be suspended thereon and a lower end adapted to be connected toa pile during the pulling of the latter; an impact member said pull rod I laterally spaced. therefrom with the axis of the cylinder inclined to the axisdftherodso-that thefen d oi the cylinder nearer .to saidrod is :at a higher elevation than the other end thereof; and a piston r reciproc'able in said fcylinder, {said cylinders being respectively arranged on oppositesides of saidlpullrod; and a connecting ma,

position thereof andextending laterally fromsaid pull 1 red when said ram is in said lower end position thereof so that in said latter position the downwardforce of said ram is converted by said connecting rods into :laterally directed force components, whereby the forces acting in downward'direction on 'said pull r'od are greatly reduced. T Z

5. A pile puller comprising, in combination, a pull rod having an upper end and being adapted to besuspended thereon and a lower end' adapted 'to be connected to a pile during the pulling of the latter; an impact member fixed to said pull rod adjacent said upperend'thereof; a ram beneathsaid impact member carried by said'rod wherefisaid ram strikes against the impact member and downwardly'a'longsaid rod to allower end'position; a housing surrounding said pull rod spacedtherefioni; elastic means interposed between said housing and" said pull rod so that said'housing is elastically supported on said pull rod; a pair of cylinder and piston meansbeing each in form of a combustion engine and having each 7 i a cylinder carried by said housing laterally spacedfrom saidpull rod with the axis of the cylinder inclined to the axis of the rod so that the end of the cylinder nearer to I saidrod is at a higher elevation than the other end thereof; and a piston reciprocable in said cylinder, said cylinders being respectively arranged Ton opposite sides of said pull rod; and a connecting rodfor each .of said pis j tons and pivotably connected at opposite ends thereof to the respective piston and said ram, respectively,said connecting rods extending substantially parallel to 'said f pull red when said ram is in said impact positionfthereof j V and extending laterally from said pull rod when saidrain 1 is in said lower end position thereof so that in said latter position the downward force of said ram is converted by said connecting rods into laterally directed force components, whereby the forces acting in downward direction of said pull rod are greatly reduced.

6. A pile puller comprising, in combination, a pull rod having an upper end and being adapted to be suspended thereon and a lower end adapted to be connected to a pile during the pulling of the latter; an impact member fixed to said pull rod adjacent said upper end thereof; a ram beneath said impact member carried by said rod for moving upwardly along said rod to an impact position where said ram strikes against the impact member and downwardly along said rod to a lower end position; a housing surrounding said pull rod spaced therefrom and having an upper end adjacent said impact member and a lower end; a pair of elastic rings interposed between said impact member and said upper end of said housing and said pull rod and said lower end of said housing, respectively, so that said housing is elastically supported on said pull rod and said impact member; a pair of cylinder and piston means; being each in form of a combustion engine and having each a cylinder carried by said housing laterally spaced from said pull rod with the axis of the cylinder inclined to the axis of the rod so that the end of the cylinder nearer to said rod is at a higher elevation than the other end thereof, and a piston reciprocable in said cylinder, said cylinders being respectively arranged on opposite sides of said pull rod; and a connecting rod for each of said pistons and pivotably connected at opposite ends thereof to the respective piston and said ram, respectively, said connectingrods extending substantially parallel to said pull rod when said ram is in said impact position thereof and extending laterally from'said pull rod when said ram is in said lower end position thereof so that in said latter position the downward force of. said ram is converted by said connecting rods into laterally directed force components, whereby the forces acting in downward direction on said pull rod are greatly reduced. t r

7. A pile puller comprising, in combination, a pull rod having an upper end and being adapted to'be suspended thereon and a lower' end adapted to be connected to a pile during the pulling of the latter; an impact member fixed to said pull rod adjacent said upper end thereof; a ram beneath said impact member carried by said rod for moving upwardly along said rod to an impact position where said ram strikes against the impact member and downwardly along said rod to a lower end position; a housing surrounding said pull rod spaced therefrom and having an upper end adjacent said impact member and a lower end; a pair of elastic rings interposed between said impact member and said upper end of said housing and said pull rod and said lower end of said housing, respectively, so that said housing is elastically supported on said pull r'odand said impact member; a.

pair of cylinder and piston'means being each in form of a combustion engine and having each a cylinder carried by said housing laterally spaced fromsaid pull rod with the axis of the cylinder inclined to the axis of the rod so that the end of the cylinder nearer to said rod is at a higher elevation than the other end thereof, and a piston reciprocable in said cylinder, said cylinders being respectively arranged on opposite sides of said pull rod; injection pump means; a fuel tank, said injection pump means and said fuel tank being located in said housing and carried by said elastically supported housing; and a connecting rod for each of said pistons and pivotably connected at opposite ends thereof to the respective piston and'said ram, respectively, said connecting rods extending substantially parallel to said pull rod when said ram is in said impact position thereof and extending laterally from said pull red when said ram is in said lower end position thereof so that in said latter position the downward face of said ram is converted by said connecting rods into laterally'directed force comp ne ts, whereby t fo ce act ng in downward direct on o sai pu r d r gr atly duced.

8. A pile puller comprising, in combination, apull rod having an pper end and being adapted to be suspended thereon and a lower end adapted to be connected to a pile during the pulling of the latter; an impact member fixed to said pull rod adjacent said upper end thereof; a ram in form of a ring piston beneath said impact member carried by said rod coaxial therewith for moving upwardly along said rod to an impact position where said ram strikes against the impact member and downwardly along said rod to a lower end position; a housing carried by said pull rod and having an upper cylindrical end coaxial with said pull rod and closed by said impact member, the outer surface of said ram being in sliding engagement with the inner surface of said upper cylindrical end of said housing so that air located in said upper end of said housing will be compressed during the upward movement of the ram; a pair of cylinder and piston means being each in form of a combustion engine and having each a cylinder carried by said pull rod laterally spaced therefrom with the axis of the cylinder inclined to the axis of the rod so that the end of the cylinder nearer to said rod is at a higher elevation than the other end thereof, and a piston reciprocable in said cylinder, said cylinders being respectively arranged on opposite sides of said pull rod; conduit means connecting the upper end portion of said housing with said cylinders so that air compressed during the upward movement of the ram may be fed into said cylinders for flushing the interior thereof; and a connecting rod for each of said pistons and pivotably connected at opposite ends thereof to the respective piston and said ram,respectively, said connecting rods extending substantially parallel to said pull rod when said ram is in saidimpact position thereof and extending laterally from said pull rod when said ram is in said lower end position thereof so that in said latter position the downward force of said ram is converted by said connecting rodsinto laterally directed force components, whereby the forces acting in downward direction on said pull rod are greatly reduced. r l

9. A pile puller comprising, in combination, a pull rod having an upper end and being adapted to be suspended thereon and a lower end adapted to be connected to a pile during the pulling of the latter; an impact member fixed to said pull rod adjacent said upper end thereof; a ram beneath said impact member, said ram being in the form of a ring piston and being slidably mounted on said pull rod coaxial therewith for moving upwardly along said pull rod to an impact position where said ram strikes against, the impact member and downwardly along said pull rod to a lower end position; a housing surrounding said ram and having an upper cylindrical end portion coaxial with said pull rod and closed by said impact member and a lower end portion, the outer surface of said ram being in sliding engagement with the inner surface of said upper cylindrical end portion of said housing so that air located in said upper end portion of said housing will be compressed during the upward movement of said ram; a pair of elastic rings interposed between said impact member and said upper end portion of said housing and said pull rod and said lower end portion of said housing, respectively, so that said housing is elastically supported on said pull rod and said impact member; a pair of cylinder and piston means, being each in the form of a combustion engine, and having each a cylinder carried by said housing at the lower end portion thereof laterally spaced from said pull rod with the axis of the cylinder inclined to the axis of said pull rod so that the end of the cylinder nearer to said rod is at a higher elevation than the other end-thereof, and a piston reciprocable in said cylinder, said cylinders being respectively arranged on opposite sides of said pull rod; a connecting rod for each of said pistons and pivotably confrom said pull rod when said ram is in said lower 5 end position thereof so that in said latter position the downward force of said ram is converted by said connecting rod into laterally directed force components; pump means carried by said lower end portion of said housing for engagement with said ram in the lower end position thereof and operatively connected to said cylinders for injecting fuel thereinto as the ram reaches its lower end position; and conduit means connecting the upper end portion of said housing with said cylinders so that air compressed during the upward movement of the ram may be fed into said cylinders for flushing the interior thereof.

No references cited.

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