US2004664A - Muzzle loading grease gun - Google Patents

Description

June 11, 1935- s. J. KRMQIMK MUZZLE LOADING GREASE GUN K Filed oct. 21, 1931 ya M m w N Z m www mv n N ,m WNNN M w QQ mv e@ L 5 m n E m m w mm, mm. am WM. N E xv Sv um, NNY Nw NN mmv @www N MN w@ N Sn Nw mw will Kw NN tlwwmkv I II n QN HN \WN Mw Ww QW N 6v@ s Patented June 11, 1935 MUvzzLE LoAniNG ,GREASE GUN` Y Steven J. Krannak, Minneapolis", Minn.; assignor 'to l'vIin-A-Max Co., MinneapoliaMinn., a corporation oflvlinnescta Y' Application october 21,

1931, serial Nb. 570,078

2 Claims. (Cl. 221447.23)

' My invention provides a'highly ecient grease gun capable of' delivering grease" under' high pressure and being quickly reloaded with grease. The grease container or barrel is provided with 5. means whereby it may be quickly reloaded through its muzzle or discharge end; and hence this grease gun is herein designated as a muzzle loading grease gun, to distinguish it from other grease guns such as those disclosed and broadly claimed in prior patents issued to` V. A. vBoker, the one No. ,1,801,069 of April 14,1931,

and the other No. 1,803,3i2, of May 5, 1931.

Generally stated, the invention consists of the novel devices, combinations of dewices andar- RV rangement of parts hereinafter described and defined in the claims.

Referring to the drawing, which illustrates the invention, whereinV like characters indicate like;

parts throughout the several views:- Fig. 1 is a vertical axial section takenithrough the complete grease gun, some parts being shown in full;

Fig. 2 is an enlarged vertical section taken axially through the lling nozzle of the barrel or grease container of the gun and showing also in section the grease discharge nozzleV of a source of. grease supply such as a large tank in which the grease is contained under pressure;

' Fig. 3 is a detail in section taken on the line 4 4 ofFg.1;and r Fig. 4 is a detail in section take-non the line 3 3 of Fig. l.

The ejector portion of the grease gun is in the form of a differential cylinder vand differential piston, in which the Vrelatively very small plunger or stem of the piston works in the small greaseejecting cylinder, and wherein the large piston head is actuated by air pressure. The large cylinder 5 is axially aligned with and rigidly connected to the relatively very small gun cylinder 5. The large piston 'I works Vin the large cylinder 5 and its relatively very small plunger or stem 8 works in the, small gun cylinder 6. A cylinder head 9 isbolted or'otherwise rigidly secured to the outer end ofc'ylinder 5 and is formed with air ports I, II, and I2 and with a valve head chamber I3, the lower en d of which isnormally closed by a screw-threaded plug Ill.

A tubular valve stem l5 works through the top of the cylinder casting 8 and ata point below the contracted upper portion `oi the iv alvef, chamber I4 is formed with a valve head. i6, which when raised; cuts` off communication between ports l0 and I I, but Ywh ich,-when depressedjopensnp 55. communication between said ports. Valve stern I5 is 'provided with `upper lateral ports I 'Ifand lower ports i8.. Tovthe extreme uppervendv ofV valve stem Iis secured a capv I9 that loosely ritsrv over the. hub 2G that surroundsthe upperportion'A of said stem l5. This cap isyprovided with a 5 gasket 2 I which, when the cap and stem arede-l pressed, is tightly V'seated against the hub*y 2G. The operation of this ,valvev will be considered lateron. f' `The cylindersiY and 6 arev rigidly secured re-A spectively lby columns 22- and 23 tothe bottom of the cylindricalw grease container .-or barrel 24. Column 22 is tubularso that it affordsl communication between the delivery end of grease-cone taining barrel 2"and the bore of small cylinder 6.v Working in the-barrel 2li is a follower-.acting pistonv 25. To the rear en d of barrel 24-is rigidly secured a cylinder head 26. An air pipe 21 connects the port l2V ofcylinder head 9 to ports 28 and 29 of cylinder head 2li. AV check valve, shown as'inthe form of a ball 30, rests on the upper end of pipe 2l and checks the flow from port v28 backward into pipe 2'l. The port V29 is normally closedAV bya valve -3I which, as shown.: is of .ball type, andfisv pressed againstr its seat by its screw, 32.applied through the topgof the head 26. The numeral 33 indicates a nipple screwed into the head' and leading to the port I0 thereof, 4This nipple 33, in practice, will be connected by a flexible pipe or hose 34 to a source of air supply under pressure such as a compressed air tank. Y Y, l i

,The gun barrelv 6, at its delivery end, is enlarged to form ka recess 6a to receive a check'valve 35 shown as in the form of a ball that permits 'a liow of grease from barrel vIi under pressure, vbut checks a backward flow. The coupling nipple 36 is screwed into the large cavity Iia of thebarrel 6 and is connected to a flexible grease delivery pipe. or hose A37. A small oil return duct 38 leads from the recess la outward of the valve 35 back into the conduit of the tubular column22. This conduit isinoi1` mally closed by a valve 39, shown as in the formi of a ball that is tightly seated by a screw 401 VA finger-operated Valve-actuatingy lever 4I is. pivoted to the column 23 .with its short end rest# ing; on the cap I 9. The long endi'o'f'this lever lll is shownas guided againstA lateral movements" but free' forfyertical movements by flangesj42v on the column 22, and its backturned free end stands in position to be engaged by a linger off a` handholdin'g the grease gun by gripping of-barrel' 2,4f'in the space between the columns v22 `an `zl232-- f To the front! or muzzle end of'the barrel 24 isV secured a head 43 into which i'sftightlyf screwed sof the threaded tubular end of'a valve casing 44, which, near its threaded outer end,is provided with an inwardly projecting annularstop flange 45. A thimble 46 is screwed into the outer end of valve casing 44 and against the flange45. Working slidably through the thimble 46 is arvalveacting nozzle 41 and onto the end of the latter is screwed the tubular nozzle tip 48. This nozzle Ytip 48 may be variously formedbut,V as shown,

is internally rthreaded and provided with an internally beveled rim 49. Y The nozzle 41 is tubular except at its inner end,

'which is left solid and is providedwith a diametrical port 5G that is normallyclosed by the thimble 46. The solid inner end of nozzle41isprovided` with an outstanding annular fiange that; is' Vnormally seated against the fiange 45 by a .coiled Y spring 52 compressed between said vflange 5I and thebase of casing 44. fj

In Fig. v2, the numeral 53 indicate Vpart of a grease-containing tankinwhich grease will be maintained vunderA considerable pressure. As shown, this tank is provided with an internally threaded grease discharge tube 54, into which is screwed the tubular externally threaded stem of a valve casing 55; the outer end of which is closed by screw-threadedfplug 56. A tubular grease discharge nozzle 51 Yworks-slidably through the plug 56 and is springpressed forward bya coiled spring 58,:4 compressed between the .inner end of the same andthebase of valve casing 55. The extreme outer end of this tubular nozzle 51 isfconically bevelledvv so as to closely fit the internally f kbevelled surface 49 of the nozzle tip 48. The extreme inner end of nozzle 51 is closed butitsaxial passage is provided with a diametricalport 59V located just infront of anoutstanding annular fiange formed Von thesolid inner end portion of said nozzle. As shown, a gasket 6I is seated against the vinner .end of the plug 6|);V Normally spring 58-woul`d press nozzle 51 outward to its limit',*w`itlf its flangeIIl seatedagainst the gasket Sian-d with its port 59 closed by the plug 56. Y

A quite heavy coiled Vspring 62 is located in the large cylinder 5 and its reduced extension` reacts against therbase of said extension yand against piston 1, and yieldinglyf'holds the sameand'the plunger 8 retracted as shown in'Fig. 1. f

' Y Operation Normally, valve to its 1imit,- thereby cutting oli communication between the air supply portIU and the inlet port Il tothe large cylinder 5; and at'such time, the rearend: of large cylinder 5 will be open to the atmosphere through the tubular valve stem I5 and its-ports I1 and I8. When the free end of lever .4I is raised, valve head I6 and its stem I5 will be moved downward as shown in Fig. 1,-thereby closing upper ports I1 and cutting-off the cylinder 5 from communication withthe atmosphere, butopening the supply of compressed air from port ID around stem .I5 and through port `I I, to saidcylinder5 and'through port '12, kand pipe 21 and port 28 to the rear end of greasecontaining barrel 24. Normally, of course, the A valve acting end of thenozzle 21 will close the' discharge `end of.barrel24 against the discharge of greasethrough said nozzle 41.. When air is admitted yinthe rear end of cylinder 5 and .to the reargend of barrel 24, air will be admitted into the latter, which will cause forward movementof the follower piston 25, .therebyv keeping the grease in barrel V24 .under-,pressure and cause the i Seme i9. 119W through thetubular commu 2,2 into;

head I6v will be pressedupward' f1.1In agrease guna provided at one end with a grease inlet and at the small gun barrelor cylinder that is in front of plunger 8, and by the said air pressure admitted into cylinder 5, large piston 1 will be forced forward, causing plunger 8 to eject the grease from gun barrel 6 under very high pressure.` Obviously, the difference in cross-sectional area of piston 1 that comparatively low air pressure on the latter will produce a veryhigh pressure per square inchon thegreasein the gun barrel 6.

Each time the lever 4I is raised as above described, one grease-ejecting impulse willbe imparted to plunger 8 and a step of forward movement will be Ygiven the follower piston 25. Check valve 30 maintains the pressure in the rear end of barrel `24* when therear end of cylinder 5 is being open to thel atmosphere to permit return of piston' 1 under theaction' of spring 62.

When grease delivery pipe 31 is connected to a' receiving nipple, after aV grease-delivery operation; the pressure' in the pipe 31 will be very high so that withfsome types ofY nipples andadapters or couplers, the release of the latter from theformer will be difficult. Thishoweven isma'del barrel 24 may be very quickly accomplished withthe device shown and describedand by anr opera-- tion Villustrated in Fig. 2, and which is as follows:`

The nozzle tip of the grease gun is engaged with and then pressed ragainst the projecting end of nozzle 51 under sufficient pressure to open the port 5|)k of rgrease-receiving nozzle and to open'r the port 59 of grease supply nozzle. These nozle port-opening sections will, ofcourse, be produced by compression of springs 52 and V58, Vto permit a, displacement of air back of the followeracting piston'25 so that said piston will be moved' Y fromthe vfrontJbackto VYthe -rear of the greasecontaining barrelz24, valve 3| must first be opened by releasing of screw 32, and under pressure fromf the supply tank 53, the grease will be forced into the-barrel 24, causing the backward `movement of fpiston 25 and complete fillingof the barrel 24 Vwithgrease.` When this filling has been accomplishedvalve 3|- should then be, again forced to its seat by screw 32, so as to close port 29.

In practice, the supply nozzle from the supply tank will advisably be located where it is close to or` accessible from the place where the grease gun would be used in greasing of carsl and the like. .This makes it1possible by the simplest kind of an action above described, to almost instantly refill the grease-containing barrel of the grease gun. Not only can the refilling of the grease gun be Very quickly" accomplished, v,but the discharge of grease for lubricating purposes by the means of the'grease-ejecting mechanism of the gun is made an easy matter, and positive delivery of greaserun'der highpressure is insured. From what has beenjsaid,V it is .obvious that various alterations Aand#changes in details of constructionmayv befmade within the scope of the invention herein disclosed'and broadly claimed. WhatI I ,claim'fisr grease-containing lbarrel its opposite end with an air inlet passage and betweenjsaidtwo noted passages a grease-outlet passage, a -normallyclosed valve in said grease intake passagefhaving a. projecting nozzle which, when pressed toward the interior of the barrel, opens saidfgrease intake valve, a rvalve in Vsaid airintake passage arranged to be openedl bv pressure toward the interior of said barrel, aV oating piston working in said barrel between said air intake port and said grease outlet passage, means for controlling the discharge of grease from said grease-discharge passage, and means for releasing the air pressure in said barrel between said piston and said air intake valve, so that said piston may be retracted when grease pressure is applied to said barrel past the pressure-opened intake valve of said grease intake passage.

2. In a grease gun, a grease-containing barrel provided at one end with a grease inlet and at its oppdsite end with an air inlet passage and between said two noted passages a grease-outlet passage, a normally closed valve in said grease intake passage having a projecting nozzle which,

when pressed toward the4 interior of the barrel, opens said grease intake valve, a valve in said air intake passage arranged to be opened by pressure toward the interior of said barrel, a iloating piston working insaid barrel between said air intake port and said grease outlet passage, means for controlling the discharge of grease from said grease-discharge passage, comprisinga normallr closed outwardly opening check valve, and means Y for releasing the air pressure in said barrel between said piston and said air intake valve, so that said piston may be retracted when grease pressure is applied to said barrel past the pressure-opened intake valve of said grease intake passage.

STEVEN J. KRANNAK.

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