US1711549A - Hydraulic jack - Google Patents

Description

May 7, '1929- iE. A. STILLMAN 1,711,549 l HYDRAULIC JACK l d L5 7 ATTORNEYS l "MaY 7, 1929- E; A. STILLMAN HYDRAULIC JACK Filed Nov. 8, 1926 2 Sheets-Sheet ATTORN EYS 'Patented May 7, 192,9.

UNITED y STATES EDWIN A. BTILLMAN, OF NEW YORK, N. Y.,

PATENT* oF'FlcE.' y

ABSIGNOR '101 THE WATSON-BTILLMAN C0.,

OIE-NEW YQRK, N. Y., A. CORPORATION F NEW JERSEY.

HYDRAULIC .Tacx

Application led. November portable Ajack of sectional construction in whichthe various parts may be readily assembled and taken apart; to provide for the admission and reliefof air to and from the fluid reservoir of the ack without liability of leakage of fluid from the reservoir when the jack is not inl use; to provide simple means for lmitingthe lift stroke of the jack ram; to 15 provide simple means for positively locking A the jack ram in raised position; and lto provide improved hand-operated means for supplyingliquid under pressure to the ram cylinder and returning the same to the jack reservoir.'

lTo .the foregoing and other ends, which will appear from the following description in detail of the preferred embodiment of the invention illustrated in the accompanying drawings, my invention vcomprises the arrangementsof parts, combinations of devices, and features of vconstruction particularly pointed out in the appended claims.

In the drawings;

- Figure 1 is a vertical sectional view taken on the line 1--1 of Fig. 3;

Fig. 2 a vertical section on the line 2-2 of Fig. 3;

Fig.3 a plan view of the jack; Fig. 4 a detail horizontal section on the line 4 4: of Fig. 2; f p

Fig. 5' a horizontal section on the line 5-5 of Fig. 1;

Fig. 6 a vertical section on the line 6--6' of Fig. 3;

Fig. 7 'a vertical section on the line 7-7 of Fig. 3; p

Fig. 8 a fragmentary Isection on an enlarged scale, taken on the saine line as Fig. 1 and vSFig. S) a vertical section on the line -9-9of Fig. 3.

The base section 10 of the jack comprises a thick metal plate from the center of which rises an integral, vertical,` cylindrical exten,

5 sion 1,1`.' The extension 11 is'open at its upper end4 and .provided with internal screw threads 12, The base 10 is formed with acir 8, 19,26. Serial No. 147,041.

cular groove-13 in--its upperface around the inner wall of extension 11, and said extension isformed with a horizontal, outwardly extending ia'nge 14 around its open` upper end.

Flange 14 is formed with a circular roove 15 1n lts upper face adjacent the outer e ge of the flange.

Packing rings 16 and 17 are seatedv in the bottom portions of'grooves 13 and 15, respecltively, and the lower ends of two concentric 'met-al cylinders18 and 19 extend into the upper portions of said grooves and are seated on said packing rings. The inner cylinder 18 is provided' adj acentits lower end'with external screw threads 20, and said threaded end portion' of the cylinder is Screwed down into the extension 1l firmly against packing ringv 16 to seal the lowerl end thereof and det-achably secure thel cylinder to the base section ofthe jack.l f

Cylinder 18 serves as a ram cylinder for the lifting ram 21 of the jack, and the two cylinders 18 and 19 form the vertical 'walls of an annular reservoir 22 which ispartly filled with oil, water, or other suitable liquid L. The flange 14 forms the bottom Wall of reservoir 22, and the to wall of said reservoir consists of a removab e metal ring 23 slidably engaged about cylinder 18 (nearA the upper end of said cylinder) and having a circular oove 24 in its under face into which slidably llits the upper end of cylinder' 19. A

suitable packingV ring 25v is confined in groove 24 at the upper end edge of cylinder 19. Y

Cylinder 18 is provided at its upper end `(alcove ring 23) with external screw threads 26,` and a nut 27 is screwed down around said threaded cylinder end against a metal compression ring 28 to firmly, but removably, lock cylinder 19 and the annular reservoir Wall or ring 23 in place; and compress the packing rings 17 and 25 and a third packing ring 29 to seal the reservoir joints. Packing ring 29 is located under compressionring 28 in a recess O'extending around the upper face of the ring-like reservoir wall 23 at the inner ed e of said ring-like wall. Nut 27 is provi ed with suitable wrench slots 27 a.

The` ram21 preferably comprises a hollow metal forging closed at its lower end and open at its upper end, as shown. It is provided with a suitable packing 31 at its lower end and with a head 32 at its upper end. `The form of a double thread. A ram elevating and lock-up nut 34 is normally threaded on the upper end of the ram to permit the ram to normally seat on the base 10 within the cylinder 18, vas shown in Fig. 1. The-nut 34 may. be also screwed down along the ram into engagement-with the upper end of cylinder 18 to positively lock the ram in any desired elevated posltion within the limits of its stroke. The nut 34 is provided with 4radial handles or grips 34 by means of which it may be turned when-in engagement with the upperend of the cylinder 18 to raise the ram into engagement with the object to be raised or moved by the ram. The steep pitch of the threads 35 permits this to be done quickly. The ram is formed with a groove 21. On the upper end of the cylinder 18 is secured a key 18 which extends into the groove 21. The key prevents the rotation of the ram and permits it to be raised and lowered by the rotation ofthe nut 34. Theram ma be readily inserted in and removed from cy inder 18.

In order that the jack may be readily handled and carried about, a pair of lifting handles 36 are pivoted on pins 37 in horizontal ears 38 on the ring-like reservoir wall 23, said handles having stop lugs y39 thereon adapted to abut against vertical stop lugs 40 on Wall 23 when the handles are rocked up consists o into horizontal position.

Li uid is withdrawn from the reservoir 22 and orced into the lower end of the ram cylinder 18 under pressure, and is returned from the ram cylinder to the reservoir, by means of a pump and a by-pass valve attachable to and detachable from base 10 as a unit. The ca sing of the pump and return by-pass valve unit a metal casting or forcin comprising a base block 41, having a flat ottom face seated on a fiat upper face ortion 10 ofthe jack base 10, and tightly, )ut detachably, heleL thereon b two screw bolts 42. The bolts 42 extend own through block 41 and are threaded into screw-threaded apertures in base 10. Block 41 is formed-with an integral vertical, cylindrical, extension 43 in which is reciprocable the large cylin drical guide head portion 44 of a small pump piston or plunger 44.

Piston 44 is of small diameter relatively to .the ram 2l and reciprocates in a pump cylinder comprising a'vertical borev45 extending down into base bloc'k41'fr`om the bottom of the cylindrical 'housing 43. Pump piston 44 is provided with a suitablepack-h mg 46. The pump pieton is reciproeable by end loosely engaged in a transverse slot 48 .throng-l1 the guide head 44 of the piston, and

having a square aperture-through its other end through which looselypasses the squared intermediate portion 49 of a 'rock shaft 49. The larger. outerend portion of shaft .49 is formed with an integrall hand-lever-socket head 50, and the smaller inner end portion 49h and said larger outer end portion of the shaft are cylindrical and journalled in bearings 51 and 52 formed in-a rear extension 54 of housing 43. A

The shaft 49 is removableendwise and is normally retained in place by a set-screw 53 slots upon removal of shaft 49 and a coverv plate 58 which is detachably held tothe rear end of guide housing extension 54 by screws 59. The slots 56 and 57' also afford clearance to permit locking up anddown of arm 47. The up er end of housing 43 is closed by a remova )le screw-cap` 60, and the piston 44---44L is adapted to be inserted and removed through the upper end of said housing when the cap is unscrewed.

, A detachable operating lever or pump handle 61 is formed' with a suitablehand grip at one end and the other end thereof is removably inserted in one or the other of two crossed slots or sockets 62 and 63 passing through the head 50 of rock shaft 49, so that the lever may be attached for fore-andaft swinging, as shown in the drawings, or for lip-anddown swinging if desired. The lever 61 is provided at its handle end with a wrench socket 61 which is adapted to be placed in engagement with the squared head'at the end of the stem ofthe by-pass valve for the purpose of operating said valve, as hereinafter described.

A passage 64 extends down from the bottom of reservoir 22 through extension 11 and then laterally through base 10 and finally upward to the flat top' face portion 10 of the base. A suction nipple 65 is preferably screwed into the enlarged reservoir end of down through baseblock 41 of the pump unit from the bottom of an intake valve chamber 67, formed in said block, to the' bottom face of the block in register with the other end of passage 64. The meeting ends ofpassages 64 and 66 are referably enlarged, as shown, and a coupling nipple 68 extends into said enlarged passage ends, and is clamped bemeans of a rock arm 47, having a rounded ffree tween the bases 41 and 10 with its rends Iirmly pressed against packing rin s 69 and 70. The

A u per end of the intake va ve chamber 67 is a screw bonnet 71 screwed into the threade upper end of-said chambenand an intake valve 72 in said chamber is normally urged downward to its seat by a coiled spring 73 to close passage 66. A horizontal passage 74 connects Valve chamber `67.with the lower end portion ofthe pump :piston cylinder 45. It w1 lbe'obvious that durm upward strokes of pump piston 44 liquid will bei sucked from reservoir 22 through nipple 165 and pas` sages (S4-and 66, past valve l72 into chamber 67 and thence through pasear@v .74' inte the, Pump Cylinder 45, i

A horizontal passage 75 extends inwardp and then rearward `:from the lower end of pump cylinder Vto theforward endof a orizontaloutlet valve chamber 76. AA Yertical passage 77 vextends down from chamber 76 to the bottom face of the pump base 41. A passage 78 extends `dovvn in base 10 from the lower end of passage 77 and then horizontally'and inallyupward through base 10 to the lower fend of the ram cylinder 418.` 'The meeting ends ofv assages 77 and 7 8 are enlarged, and a coup ing nipple 79 extends into' said enlarged passage ends and 1s clamped tightly between bases`10 and 41 with its ends firmly pressed a ainst acking rings 80 and 81. An outlet va ve 82 1n chamber .7 6

is normally7 urged forward. to its seat by a1 coiled spring 83 to close the rear fend of pas-4v sage 75. The .rear end of valve chamber 76 is closed by ascrew bonnet 84 screwed into the threaded rearend of said chamber.

It will be obvious-that on down strokes'of the pump piston 44, valve v72 will be seated and valve 82 .will be unseated, so that liquid which has been drawn'intothe pump c linder4 of the reservoir 22. The valvecage is'formed with passages 86 through the outer end therey of connecting the interior' ofthe cage with'- the interior of the reservoir 22, and the passage 87 connectsthe interior of theeage with the interior ofthe ram cylinder 18.` Aball valve 88 is normallyheld to its seat' at the afd 'means' comprises e za-j cup-'like ball-valve .cage 85"'having its .open end screwed into thexenlar ed threaded outer v -gend of a passage 8 7 exten lng through cylinder 18 a short distance below the upper end inner 'end of the enlarged portion of passage 87 by means of a coil spring 89 in the valve ca e. Y

t will `be obvious/that whenever the ram 21 is forced upward far enough for the lower end of the ram to uncover passage 87, continued operation of' the pump will simply result 1n the forcing of liquid out througi4 passage 87 pastthe check vvalve 88 and thence vthrough the passages 86 back intothe ,reser- Voir 22. It .will iilso be "obvious that if the jackshould be thrown over on its side in hanl' dling, or when not in use, the valve 88 will prevent leakage of the liquid L from the reservoir'22 through the port 87 and out around the threaded exterior of the-rain 21.

It is :frequentlyI desirable to hold up av load with a jack for longA periods of time. When so'A l" this is attempted with a hydraulic jackit has been found that the ram is liable to drop owing to slight leakage of fluid past the pump valves. -It will be obvious that, with the present jack, when it is desired to maintain the ram 2l in any adjusted elevated position, it is simpl necessary to run-the lof-king nut 34 down t e externally` screw-threaded ram until the lock nut engages the upper end of the ram cylinder 18, whereu on the ram will be. positively held up by tie locking nut. When it is desired to again lower ythe ram the locking nut will be screwed back' up to its normalposition at the upper end of the ram.

I n order to lower the ram 21, ater `elevaf tion thereof by operation ofl the pump, I I

have provided means whereby theli uid in the ram c llinder may be returned tot ie reservoir. 'lhis means comprises byfpass -pas- 1 sages controlled by a by-passyalve 90 for passing the iuid back aroundthepump cylinder .and pump valves. The by-pass valve 90 comprises a cone valve on the .inner end of the Valve stem 91, which extendsdownstem '91 has an enlarged screwzthreaded por- .wardly and rearwardly linto a downwardly and rearwardly inclined by-pass Valve chamber 92 formed inthe base block 41. The valve 110` t-ionj9-1* adapted to be screwed in and out :in arrfinternally screwsthreaded bushing 93.

Bushing 93 has a reduced externallyscrew I threaded portion screwed intothe enlarged tlireaded outerI end of the valve chamber 92 'against a^ vpacking 94 surrounding the inner ofthevalve stem. The valve stem 91 oflfnied at'its outer end with asquared khead 4 1*? normally housed within the cup-like youterend of the'bush'ing 93 when the valve SiO-iis screwed inward `against its seat'at-the rear end ofy the ,valve chamber 92.

from

1e ram 21. The-'valve 90 maybe operated vby means of a key 96 held tothe base -blockfl of the l pump casingby lneansof a vsuitable chain l `The valve 90 is screwedinward to its seat whenqit is desired to operatethe jack 'to lift ,a load, and is-screwed outward awa -its seat when itis desired to lower chamber `76 and then upwardly and to lower a load which has been lifted by the 97. and* provided with a socket 95 for receiving the squared head 91b 'of the stem 91 of 1 the ley-pass valve 90. If desired the key 96l may be dispensed with because the handle socket 61 is always available for use in operating the valve 90 when the jack is in use.-

In the event that the jack is placed in such Aa position that the valve 90 cannot be oper- It will be obvious that, when it 'is desired pumping upv of the ram 21, itis simply necessary to screw the valve 90 outward away from its seat, whereupon iiuid will be forced out of the ram cylinder 18 through passages 78 and 77', valve chamber 7 6, passage 98, and

- then past the unseated valve 90 into valve chamber 92. The returning fluid will then flow from valvechamber l92 through passages 99, 66 and 64 back into the reservoir 22.

It is desirable that air'should be permitted to flow into the upper end ofthe reservoir 22 when liquid is pumped out of the reservoir and should be permitted'to escape from the upper end of the reservoir when liquid is returned to the reservoir. Ihave provided an automatic air inlet and exhaust valve device for this purpose which is located inside of the reservoir and so constructed as to prevent leakage of liquid therethrough from thereservoir in the event of thejack being thrown upon its side when not in use.

a cup-like casing` section 100 located within the upper end of the reservoir 22 and having a tubular threaded-extension .100'L at its upper end screwed -into the enlarged lower end of an Aair passage 101 which extends vertically through the ring-like. top wall 23 of the reservoir, erably extends over and is spaced slightly above the upper end of passage 101, as shown, to guard against clogging of the passage by dirt or the like. A second cup-like caslng section 102 is screwed up into the open lower end of the casing section 100 and is provided with a port-103l extending through the bottom wall A thereof.' A' disk-like air exhaust valve 104 of slightly lessdiameter than the internal diameter of the casing section' 100 is .mounted the casing. section 102by -mans of a vrelatively stii coil spring 105.V lThe valve 104 The locking nut 27 pref# has a central aperture 106 which is normally closed by a, disk valve 107 fixed on a suitable guide stem. Thev air inlet valve 107 is nort mally held seated against the lower face of the lar e exhaust valve 104 by meanspf a relative y light coil spring 108, and said valve 107 is located withinI the casing section 102 vacuum created in the upper end ofthe reservoir, to permit air to flow from the exterior of the reservoir v1a passage 101, casing section 100, aperture 106 in valve 104, casing section 102, and port 103, .into the reservoir. When liquid is forced back into the reservoir during lowering of the ram 21, valves 107 and 104 will be forced upward against the resistance of spring 105 in unison, and air will escape through port 103, casing section 102,

and around the outer edge of valve 104 into casing section 100 from which it will escape .to the atmosphere bythe passage 101. If the jack should be vturned upon its side in handling, or when not in use, valve 104 will be held to its seat by the relatively stiff spring 105, and valve 107 will be held to its seat by light spring108, so that escape of liquid through the air valve device will be prevented.A 5 Y The reservoir 22 is adapted to be partially filled with liquid L through a filling passage 109 extending through the ring-like-top wall of .the reservoir, said passage having an enlarged outer end portion into which' is screwed a closure plug 110.

What I claim is:

1. In a hydraulic jack, an upright ram cylin'der, 'a liquid reservoir surrounding Said cylinder, a `valve cage held to the ram cylinv der adjacent the upper endof said cylinder The automatic rair-valve device comprises and having open communication with the reservoir and cylinder, a check valve in said cage, a spring in said cage for normally holding the valve in position to close communication between the .cage and ram cylinder, a ram in the ram cylinder and adapted to move upwardly therein beyond the point of communication between the cylinder and valve cage, and means 'for withdrawing liquid from the reservoir and forcing itinto the ram cylinder below the ram'.

2. In a'hydraulic jack, a ram cylinder, a ram in said cylinder provided with anexternal screw thread, means'holding'the ram against rotation inthe ram cylinder, a liquid reservoir,4 a pump for 'withdrawing liquid vfrom the reservoir and forcing it into one end of the ram cylinder to move the ram by fluid pressure, and a ram elevating and lockup nut threaded o n the ram' and adapted to be rotated in abutting engagement with the upper end of the ram cylinder to move the i y Athe pump casing and-removable with the lat-v ram into work-engaging position independently of the fluid pressure means.V

3. In a hydraulic jack, a base; means mounted-upon the base and cooperating with.

it to form a ram c linder and a liquid reservoir, the base having passages therein leading from the reservoirand ram cylinder; a

ram in said cylinder; and a pump unit com'- prising a casing detachably mounted upon the base and forming a puin cylinder and outlet and inlet passages leading to said passages in the base, a piston in the pump cylinder, means carried by the pump casing for manually operating the piston, valves carried by the casing for controlling the flow of liquid to andfroin the pump cylinder, and

manually operable. valve means carried by i ythe casina' to direct liquid fromA the ram cylinde'r bacr ram. 4. In a hydraulic jack, a base; means to the reservoir for retracting the 's mounted upon thebase and cooperating with it to form a ram cylinder and a liquid reservoir, the base having passages therein leading from the reservoir and ram cylinder; a

ram in said cylinder; and a pump unit com' prising a casing detachably mounted upon the base and forming a ump cylinder and outlet andinlet passages eading to said pas sages in the base, a piston inthe pump cylinder, valves carr-ied by the casing for control.-

ling the flow of liquid to and from-the pump cylinder, and manually operable valve means carried by the `casing to dir-ect liquid from Y the rain cylinder back to the reservoir for re- `traeting the ram. v l 5. In a hydraulic Jack, a base; means mounted upon the base and cooperating With it to vform a ram cylinder and a liquid reservoir, the base having passages therein leading frointlie reservoir and ram cylinder; a

rain in said cylinder; and a pump unit comprising a. casing detachably mounted upon the base and "forming a pump cylinder and outlet and inlet passages eading to said passages in the base, a piston iii tlie'pumpeylinder, and valves carried by the casing for controlling the flow of liquid` to and from the pump cylinder.

6. In a hydraulic jack, a base; means' mounted upon the base and cooperating with it to form a ram cylinder and a liquid reservoir, thebase having passages therein leading from the reservoir'and ram cylinder; a rain in said cylinder; and a 'pump unit coinprising a. casingv detaehably'inounted upon the base and lforming a'p'ump cylinder'and outlet `and inlet passages leadmg to said passages in the base, a-piston in the pump'cylin-- der,' 'pistonoperatinv means carried solely by ter, and val-ves carried byithec'asing for controllin'g he flowv of liquid-to' andfrom .thel

pump cylinder;

7. -hydraulic jack'comprisng a main jack section including means forming ajram cylinder and a liquid reservoir; fluid connections leading fromy said cylinder and reservoir; a ram in the cylinder; and a unitary pump section, detachably mountedupon said main section, connected to said fluid connections and comprising a pump. means to maniicircling the rain cylinder and detaehably held in engagement with the' upper end of the tubularcasing, said top Wall having a filling .opening and an air port therethrough; a ren'iovable closure' for the filling openingya pair of jack-carrying handles held to the ring-like wall member; an" automatic, air valve device carried by said wall member to communicate with thesaid air port and adapted to admit air intosaid reservoir through said port upon Withdrawal o'f liquid from the reservoir and to permit air to escape through' the 4said portiu'pon return of liquid to thek reservoir; and a pump having its intake and its outlet connected to the reservoi and rain cylinder respectively.

vertical ram cylinder held at its lower end to the base; a ramin said cylinder; a tubular casing surrounding the ram cylinder held to the base. said casing'cooperating with the rain cylinder vand base to form the side and' bottoni walls of a liquid'reseivoir; a top Wall men'ilier Jfor the reservoir encircling the rain -c yliiider and detachably held in engagement with'tlie upper end of the tubular easing, said top wall having a lilli'ng opening'and an air port therethrough; a removable closure for the Iilling opening; a pair of jack-carrying handles held to the ring-like Wall member; an automatic air valve devicesecured to the 9. AIn a portable hydraulic jack, a base; a-

underside of said member. and projecting into the li uid reservoir` said valve device control- ,ling t ie. inlet to and exhaust from said reser' voir' and a'detachable pump unit mounted on the base, said unit including a pum-p,

means to control the low vof fluid from the reservoir through the pump tothe ram cylinder, and means tocontrol the 'How from said cylinder back to jthe said reservoir, this latter means including'a manually operable control valve.

10. A hydraulic jack having a liquid reserj voir;l an. upright ram cylinder; a ram in the y cylinder andmeans for withdravving liquid y.1.30

from the reservoir and forcin it into the ram uncovered by the ram when'the lower end of cylinder beneath the ram, c aracterized by the ram approaches the upper end ofthe oyl- 10 the fact that means are provided for deterinder; an a check valve is provided in said mining the maximum lift ofthe ram by the li uid return seating toward the ram cyl- 5 1iquid,comprisinga1iquid return connectin -in er. p

the ram cylinder and reservoir, one end o In testimony whereof I hereunto axmy which return opens into the upper portion of signature. theram cylinder and is so located as to be EDWIN A. STILLMAN.

Images