US2413044A - Grease pump - Google Patents

Description

A. L. GRISE GREASE Puur Filed June 11, 1945 Dec, 24, 1946.

2 Sheets-Sheet l JE, 7gg@ Dec. 24, 1946.- A. L. GRISE 2,413,044

` GREASE PUE? Filed June 11, 1945 2 sheets-sheet 2 'Patented Dec. 24, 1946 UNITED STATES :PATENT oFFlMcE Alfred L. Gris,GSI;Eri1sgliell:Mllass., assignor to Gilbert & Barker Manufacturing Company, West Springfield, Mass., a. corporation of Massachusetts Appucauon June 11, 1945, serial No. 598,776

4 Claims. l

This invention relates to improvements in grease pumps and, more particularly, to grease pumps which may be used effectively with greases of various consistencies from light to heavy and with greases at various temperatures.

The invention has for its principal object to provide an improved means for priming the' grease pump cylinder and insuring that a full charge is delivered into the latter regardless of whether the grease is warm or cold or whether it is of light or heavy consistency.v

More particularly, the invention has for an object to provide a priming pump which is located below and is of larger capacity than the grease pumpand which is adapted to force some of the grease which it pumps into the grease pump and to ley-pass the rest, the arrangement being such that the heavier the consistency of ,the grease, for less the amount that is by-passed and vice versa.

'I'he invention has for a further object to provide for the delivery of the by-passed grease into an area surrounding, and closely adjacent to, the intake of the priming pump for the purpose of avoiding, or at least substantially re`- ducing, the tendency to cavitation.

The invention will be disclosedwith reference to the accompanyingdrawims in which,

Fig. 1 is a small scale exterior elevational view showing the manner of mounting the grease pump in a grease dispensing apparatus;

Fig. 2 is a fragmentary view taken in the same direction as Fig. 1 but drawn to a larger scale and showing the complete grease pump with its inlet and outlet passages;

Fig. 3 is a sectional elevational view drawn to a still larger scale and showing in full detail the grease pump proper, its associated priming Fig. 5 is a sectional plan view taken on the i line 5-5 of Fig. 2;

Fig. 6 is a fragmentary cross sectional vview taken on the line 6--6 of Fig. 5.

Referring to these drawings; the grease pump is adapted to be applied to an original container o'f the grease to directly dispense the grease therefrom. That is, the pump is suitably supported from or above the container with its barrel extending downwardly into the same, terminating near the lower end thereof. As one example, a grease drum I, with its top cover removed, is mounted in cabinet 2 and the pump is contained in a barrel t which is supported (Cl. 10S-203) 2 from the top wall' of the cabinet and extends downwardly into the drum, with the intake 1ocated close to the bottom 'of the drum. A follower plate 4 may be used in the drum, when necessary, as it is with the heavier greases, such.

` follower resting on top of the grease and closely tting the drum and the grease pump. In this case, and as best shown in Fig. 2, the pump barrel is supported from the lbase or lower head 5 of a iiuid pressure motor of the reciprocating piston type, indicated as a whole at 6. head E has a.' central depending hub 1, tting into the upstanding hub of a, plate 9 which rests on the top wall of the grease cabinet 2 or such plate may equally well rest on the cover of the grease drum. The hub 1 has a shoulder whichrests upon the upper end face of hub 8 and supports the pump and its driving motor.

Any form of drive for the pump may be used. The driving motor 6, indicated herein, may for example be of the type shown in my copending application Serial No; 598,775, led June 1l, 1945. The piston rod of the motor is shown at I0 and it extends through the head 5 and a' suitable stuiing box and downwardly into the pump barrel 3.

The upper end of the pump barrel S is xed,

las by the screw threads shown, to the lower end o1' 'an outlet pipe II. which in turn is xed, as by.v the screw threads shown, to an adapter I2, screw threaded into hub 1. Fixed, as by the screw threads shown, to the lower end of the grease pump barrel 3 is the upper end of the barrel I3 of a priming pump. Threaded on the lower end of barrel I3 is a foot valve casing I4. The barrel I3 and casing Il are of the same diameter and of larger diameter than the barrel 3 or pipe II. A thin-walled tube I5 of the same outside diameter as the barrel I3 and casing Il is secured to the upper end of the barrel I3 and extends upwardly encompassing the barrel 3 and pipe II and terminating near hub 1. This tube, with the barrel I3 and casing I4, afford a smooth cylindrical surface along which the follower 4 can move up and down and which it can t with reasonable closeness.

The'grease pump cylinder, formed within barrel 3, is shown at I6. Reciprocable within cylinder I 6 is a piston comprising a body I1, having a long upwardly-extending hollow hub I8 and a depending hollow stud I9, on which is mounted the packing 20 and a washer 2|.l 'I'he upper end of the piston rod 22 of the priming pump is threaded onto the lower end of stud I9 and clamps the piston packing to its body.

The.

The motor piston rod I extends downwardly through pipe II, leaving an annularspace 28, and into the cylinder I8 with its lower end threaded into the upper end of hub I8. Communication between the lower and the upper side of the grease pump piston may be had by way of an axial passage 2Q, formed partly in the piston and partly in rod 22 and connected by radial openings 25 in rod 22 to theipriming cylinder to be described and by radial openings 26 in the hub I8 to the cylinder I5. Intermediate the ends of passage 24 is a .seat 2.1 on which rests a ball valve 28, the upward movement of which is limited by a stop 29, secured, as by the screw threads shown, in the hollow hub I8.

The priming cylinder 30, formed within the barrel I3, is substantially larger in diameter than the cylinder I8. The upper end of cylinder- 30 is in constant yand valveless communication with the lower end of cylinder I8. In cylinder 30 is a piston comprising a body 3l, screwed onto the lower end of rod 22, and packing 32 mounted on the stud-like lower end 33 of the body and held with a washer tby a nut 85 to the body 3|. There is an axial passage 36 leading from the lower end of stud 33 upwardly into the body 3| and communicating with the cylinder 30 above the piston packing 32 by means of a plurality of radial passages 3l in the piston body. A valve seat 88 is formed` in passage 38 intermediate the ends thereof and resting on 'this seat is a ball valve 3Q, the upward movement of which is limited by a pin 40 xed at' its ends in body 3i and spanning the upper end of passage 36.

The casing Id contains the inlet passage di which has a seat l2 adapted` to be engaged by a foot valve d3, having a plurality of radial guide webs M, which slidably support it in the cylindrical bore d of casing ld, The bore 45 communicates at all times with the lower end of priming cylinder 3i). Valve d3 is moved by gravity into closed position and is lifted by suction on the upstroke of the priming piston.

Means are provided to carry away from the upper part of thepriming cylinder 3B any excess grease that cannot be taken up by the grease pump piston. Such means includes a passage d6 formed in the barrel i3 and extending from its lower end upwardly to a point above the upper end of the stroke of the priming piston where it opens into the priming cylinder by means of aradial passage d1. In theupper end face of casing ld is an annular groove 138 with which the lower end of passage dl communicates. In the casing I are formed a plurality of longitudinal passages a9, the upper' ends of each communicating with groove d and the lower ends with the grease drum at points close to the inlet passage ill. As shown, the lower end of casing Irl is made square to receive a wrench and there are four passages 39 spaced ninety degrees apart and opening through the shoulders relieve excess pressure caused by expansionof the-grease in that part of the priming cylinder below the priming piston.

The outlet of the grease pump is by way of the annular passage 23 which opens into a chamberl 51. The passage 56 has -a seat intermediate its ends and a springl pressed check valve 58 cooperates with said seat to prevent return iiow of the pumped grease.

Relief for excess pressure 'caused'by expansion of the grease in the outlet passage 56' and the hose usually connected thereto, is provided for by a spring-pressed relief` valve 59 (Fig. 5) which normally engages a seat in a passage 80, formed in head 5 and leading from the passage 56. A passage 6I connects passage E0 to a vertical passage 82 (Fig. 6) which extends downwardly to the base of hub 'I and opens into the grease drum. Expansion of grease in the passage 23 and chamber 55' will open valves 58 and 58 and' excess grease will escape by way of passages 6I and 62.

Leakage past the piston rod I0 is likewise conveyed to the drum by a passage 63 which empties into the upper end of passage 62. YPassage 63 extends through the sleeve-like wall 68 of the i stung box and communicates with an annular l 'H in the lower end of sleeve Sli is pressed upwardly by a spring 'I2 to compress the packing 'I6 against gland 66 and through the latter to compress the packing 59. Leakage past the pist0n rod IIl will be collected in groove 5l flow through holes 66 into groove 65 and from the latter by passages -63 and 62 into the upper end of the grease drum.

In operation; on an upstroke of the piston rod Iii, the grease pump piston and priming pump piston are simultaneously raised from their lowerr'nost positions shown to vthe positions indicated by dotted lines. The partial vacuum created below the priming piston in the priming cylinder causes foot valve i3 to open and grease is drawn into the priming cylinder. At the same time, grease which has previously passed through the priming piston into the space above it is lifted upwardly and forced into the lower end of the cylinder i6. So also, grease which has previously passed through the grease pump piston into the space above it is raised upwardly and forced into outlet passage 23 to be eventually delivered through the latter and into chamber 55' and through passage 55 to the dispensing hose. On a succeeding downstroke, the foot valve closes and the piston valves 2% and 39 open so that the pistons pass through the grease, whereby charges of grease are transferred from the lower to the upper Sides of each piston.

As the pistons'rise, the priming piston forces grease into the lower end of the cylinder I6 and packs it, full. The area of the annular space between the wall of cylinder 30 and rod 22 is several times (in this case about four times) that of the area between the wall of cylinder It and rod 22. Accordingly, if the priming piston draws in a full charge of grease, only part of that charge can be forced into the grease pump cylinder. The remainder must escape and it does so by way of the` passages 4T, t6, groove d8 and passages 49 into the grease drum. With the lighter greases. unless cold, the priming piston will draw in a charge more nearly equal to the amount that is theoreticaly possible and the greater part of this charge will be by-passed back to the grease drum. While the by-pass is of relatively small cross sectional area, it will present much less resistance to light greases and warm greases than to greases which are cold or which are of heavy consistency. As to cold greases and heavy greases, much less than the theoretical charge of such greases will b taken in by the priming piston and less of the charge will have to be by-passed. The small bypass presents so much resistance to the flow of heavy or cold greases therethrough that grease will not by-pass unless and until the grease pump cylinder has been packed full. The arrangement vthus assures that the grease pump cylinder receives a full charge of any kind of grease that may be in the drum or other grease container.

While the lay-passed grease may be ejected into the drum in various locations, it is preferred to do so in the manner herein disclosed. That is,

the ley-passed grease is `delivered downwardly is so directed as to fill any cavities that exist' and, in fact, so as to prevent or at least substantially reduce the tendency to their formation by forcing the by-passed grease into thearea where the cavities are most likely to form.

The invention thus provides an all-purposel grease pump for use in dispensing greases of arious consistencies and capable of emcient use irrespective of the consistency of the grease dispensed.

I claim: l

l. A pump, comprising, a pump cylinder, a priming cylinder having its outlet end connected to the inlet end of the pump cylinder, an inlet valve opening into the other end of the priming cylinder, interconnected pistons one in each cylinder, each piston having a passage interconnecting opposite sides thereof, a valve for each passage, each valve closing on the delivery stroke of its piston and opening on the return stroke to permit grease to be transferred fromthe suction to the discharge side of its piston, the effective area of the priming cylinder being greater than the eective area of the pump cylinder, and a 6 l by-pass of relatively small area extending from the outlet part of the priming cylinder in a direction parallel with the axis of the priming cylinder to the intake end thereof.

2. A pump, comprising, a pump cylinder, a priming cylinder having its outlet end connected to the inlet end of the pump cylinder, an inlet valve opening into the other end of the priming cylinder, interconnected pistons one in each cylinder, each piston having a passage interconnecting opposite sides thereof, a valve for each passage, each valve closing on the delivery stroke of .its piston and opening on the return stroke to permit grease to be transferred from the suction to the discharge side of its piston, the eective area of the priming cylinder being greater than the effective area of the pump cylinder, and a by-pass of relatively small area extending from the outlet part of the priming cylinder and delivering the by-passed grease inv a series of jets surrounding the inlet of the priming cylinder.

3. A pump, comprising, a pump cylinder, a priming cylinder having its outlet end connected to the inlet end of the pump cylinder, an inlet valve opening into the other end of the priming cylinder, interconnected pistons one in each cylinfder, each piston having a passage interconnecting opposite sides thereof, a valve for each passage, eachvalve closing on the delivery stroke of its piston and opening on the return stroke to permit grease to be transferred from the suction to the discharge side of its piston, the effective area of the priming cylinder being greater than the effective area of the pump cylinder, and a by-pass of relatively small area connected to the priming cylinder at a point which at all times is on the discharge side of the priming piston and extending to the area outside the priming cylinder andy adjacent the inlet end thereof.

4. A pump, comprising, a pump cylinder, a priming cylinder having its outlet end inv open and unrestricted communication with the inlet end'of the pump cylinder, an inlet valve opening into the other end of the priming cylinder, interconnected pistons one in each cylinder, each piston having a passage interconnecting opposite sides thereof, a valve for each passage, each valve closing on the delivery stroke of its piston and opening on the return stroke to permit grease to be transferred from the suction to the discharge side of its piston, the effective area of the priming cylinder being greater than the effective area of the pump cylinder, and a by-passl of relatively small area connectedI to the priming cylinder at a point which at all times is on the discharge side of the priming piston and extending to the area outside the priming cylinder and adjacent the inlet end thereof.

ALFRED L. GRIS.

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