US1589240A - Process of making pumps - Google Patents

Description

P. L. SCOTT PROCESS OF MAKING'PUMPS riizinu Filed Dec. 15,1919

June 15,1926. 1,589,240 I 6 v '1 I V r C [Wk/5 72 to?" Witness f/zz'Zz'p l ficotzf.

Patented 'June 15, 1926.

UNITED STATES PATENT oFFicE'.

PHILIP LANE scor'r, or CHICAGO, rnLrNors'assreNon'ro sornn-n'msnx. raaozron CORPORATION, or LA ronrn, INDIANA, A CORPORATION. or NEW YORK.

rnoonss or MAKING ruins.

Original application filed December 15, 19 19, Serial No. 344,883. Divided and this application filed December 15, 1920, Serial No. 430,825. Renewed January 6, 1926.

My invention relates to improvements in process of making pumps. Among the ob jects of my invention are to provide a pump in which all working parts are properly lubricated and in which leakage is prevented.

Another object is to provide a pump.

wherein the clearances will be sufiiciently minute to permit pumping to be done by piston or plunger without any packing and Without disastrous leakage. 1

In connection with carrying out my .invention, I find that preferably one ofrthe wearing surfaces either the plunger of seat ought to be soft iron and the-other of steel.

At least, one ought to be harder than the other, although this is not absolutely essential;

It may be saidiin this connection that.

one'reason why cast iron is satisfactory for this purpose is that even though the soft iron warpsand develops in pumps lumps and distortions which engage the plunger, these irregularities are immediately worn down withoutsticking. If bronze were used, we

would have bindingof the piston as soon as any appreciable distortion has taken place. Other objects will appearfrom time totime in the specification.

.My pump,,in the form here illustrated, is

particularly designed for'use with direct injection hydrocarbon internal combustion engines, where high pressures are ,used. It

may, however, be adapted to a variety of other uses, for example'wherever -apump is required. One form is illustrated in section in the accompanying figure, wherein A is a jacket impervious to oil, and in the form here illustrated, 'is made'of steel.

' B is an inner liner of such material that 9 the oil may penetrate in it and through it, and which is of such a character that it fula .fills the requirements above pointed out in connection with the close clearances and fits required. In this cas'e, it ismade of cast 5 iron. B is a bore in the liner B and en larged' at B to provide. an oil pocket or chamber. B isa bore'inthe side of the liner B and extendingthrough the jacket A. B is another bore in the linerB, extending throughthe jacket A. t

C is an v1 let connectl into the bore B ofthe jacket A. It has the centralbore C which is enlarged at C and prov. dedwitha beveled valve seat C upon positioned.

on, screw-threaded This double valve arrangeuicnt constitutes the inlet side of thepump.

D is a discharge connection, screwthreaded into the jacket A in the bore B It has the central bore D which terminates at one end in the beveled face D against which the spring D abuts. D is a packing. D is a valve sleeve having the pocket D in which is the beveled valve seat D. D is a valve adaptedto be seated on the valve seat by the spring D. D is'a narrowed bore in the valve sleeve in'which the valve D -is D are vanes on the valve adapted to contact the sides of'the bore and to cause the proper seating and alignment of- 'the valve.

E is a plunger having the enlarged head E E is a collar secured on the head. E is a springabutting at one end against the liner B and at the other against the collar E The pump may be driven by any suitable means such as a cam or rocker arm, not here shown, forming no part of this invention. Thereis theadditional feature of lubrication due to the porous quality of the iron.

It has beenfound in practice that the oil will work through the iron and back along the piston through its entire length. This results in a film of'oil entirely surrounding the piston throughout its length and'thoroughly 'lubrica'tingit without the medium of any additional channels or passages.

In my apparatus, I do .not know exactly what the clearances are between the-plunger. and the plunger seat. They range probably somewhere in the neighborhood of a ten-thousandth of an inch. The reason why I do not know what the clearances are is because the parts are made originally with practically no clearance except that necessary to make it possible to force the lunger into the seat with a pressure. of rom 15 lbs. up, the plunger and seat being lubricated and then reciproeated with reference one to the. other and thus being la ped in.

together with an oil tight wbrking t Without the use of any abrasive material. 1,

lOO

or similar types of engine although it may be-used for pumping any liquid.

It is an interesting fact in connection with this particulararrangement of vpump and bearing surface, that when the p1l1n1)1S properly made, we have a"pump in which the plunger is actually freer to reciprocate than it wouldbe the normal type ofstufi'- ing box were used and this characteristic is one of the essential or at least exceedingly the pump smooth and responsivein'its action.

\ Vhen the plunger and the bearings are fitted as I have above suggested, theirrelation is such that the plunger will be suspended or centered in'the; seat by a very thin film of oil and this film is preferably so thin that the surface tension of the oil is sufficient to resist the shearing action resultant from the movement of the plunger with respect to the seat even though the pressures are ,very great, and this gives us a continuousoil film so that there .is a negligible frictional resistance to the movement of the plunger and it is this surface ten- .sion also which probably prevents, or is largely active in preventing any leakage between the plunger andthe seat. This is sharplyv contrasted with any arrangement where a stufiing box is used because the stuffing'boxhas for its characteristic that it tends to break the oil film thus increasing the resistance to the movement of the plunger and also doing away with'any benefit which maybeobtained from the surface 7 tension-resisting the leakage.

It will. be understood that as the pump warms up to its work it develops a sensi ble heatwhich may be variable, andas aresult of this the diameter of both the plunger and the seat changes in different ratios. [In order that leakage may not take place during normal operation, it is neces- 'sary that theplunger must expand more than the barrel, and therefore one'o'f the members, either the plunger orithebarrel, must be capable of wearing away sufficiently to produce such a fit as will satisfy the necessary conditions of permanent operation.

The 5 and operation of my invention are as follows 2- When the piston is. drawn out by the spring a suction is produced and the two valves on the suction side are opened by it against the pressure 'of their springs. By I this means oil is drawn into the pumping-- chamber. When the piston is forced back charge valve isunseated by it, and the liquid As the movement otthe piston continues, pressure is created and thedisis forced out throughthe discharge con-- nection,

1 find that the close fits provided make leakage along the plunger practically impossible'and it is a fact that a pump handling upwards of 400 cubic inches of oil per hour at-pressures ra'ngingfrom 3000 to 8000 lbs. per square inch, will not leak more than a few' drops of oil past the plunger during an hour'period. -In fact there is less leak vention, and I wish therefore, that my drawings be regarded as in a sense dias grammatic. What I claim 1s- 1. The processof manufacturing" a pump which consists in forming a cylindrical seat, and a unitary plunger of su same diameter lnsertmg the plunger 1n the stantially the r. age than on any stufiing box, that could important characteristics because it makes seat and forcing it in under pressure, then reciprocating one of the parts with respect to the other until a smooth working oil-tight fit is obtained. Y

2. The process of manufacturing a pump which consists informing a cylindrical seat, and a unitary plunger of substantially the same diameter inserting the plunger in the seat and forcing it in under pressure, then reciprocating one of the parts with respect to the other until a smooth working oil-tight fit is obtained without introduction of any abrasive material.

3;, The prooessof manufacturing a pump which consists in forming a cylindrical seat, and a plunger of substantially the same diameter, one'of-them' being of softer" material'thanthe other, inserting the plunger in the seat-and forcingit in under pressure,

then reciprocatingone of the parts with're- 7 spect to the other until a smooth' working oil-tight fit is obtained. 4 I 4. The process of manufacturing a pump which consists informing a cylindrical seat and-an uncompressible plunger Ofsubstan 'tially the same diameter, insertlng the plunger in the seat, forcing-it in under pressure, then reciprocating one of the parts with respect to the other until a 'smoot working oil-tight fit is obtained. i 5. The process of manufacturing a ump which consists in forming a cylindrica seat "and an'uncompressible plunger of substantially the same diameter, insertingthe plunger in the seat, forcing it in under pressure, then reciprocating one of the parts with respect to the other until a smooth Working oil-tight fitis obtained, Without theintroduction of any abrasive material. 7

6. The process of manufacturin a pump which consists in forming a cylin rical seat and an uncompressible plunger of substan-- vwhich consists in forming a cylindrical seat and an uncompres sible plunger of substan tially the same diameter, lubricating the parts, inserting the plunger in the seat, forc- 1t i-n underQpressure, then reciprocating one of the parts with respect to the other until a smooth'working oil-tight fit is obtained,

Without material.

8. The process of manufacturing a pump which consists in forming a cylindrical seat,

the introduction of any abrasive and aplungerof substantially the same diameter, the seat bein of softer material than the plunger, inserting the plunger inthe seat and forcing it in under'pressure', then reciprocating one' of the parts with respect to the other untila smooth working oil-tight 4 fit is obtained. f I Signed at Chica 0, county of Cook and State of Illinois, t is tenth day of December, 1920. 1 'o PHILIP LANE SCOTT. 1

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