US2774380A - Diaphragm annulus with a spring therein - Google Patents

Description

Dec. 18, 1956 w. HUDSON ETAL 2,774,380

DIAPHRAGM ANNULUS WITH A SPRING THEREIN Filed April 28 1952 INVENTORI) .1 ifflz/mL/vupso/ md BY JFK/9049155,

United States Patent DIAPHRAGM ANNULUS WITH A SPRING THEREIN Application April 28, 1952, Serial No. 284,722

1 Claims. 01. 137-193 This invention relates to a diaphragm device, especially a diaphragm pump, and to a diaphragm comprising a working annulus having opposite walls which are mechanically supported from each other, as by a helical spring annulus. In some respects, the invention is an improvement of the generic subject-matter of the copending application of Charles D. Hoover, Serial No.

. 89,448, filed April 25, 1949.

It is the primary object of our invention to provide a diaphragm device and a diaphragm therefor which will operate over a wide range of temperatures, especially at extremely low temperatures of the order of 65 F. It is an object of our invention to provide a diaphragm in which opposite walls are mechanically supported from each other in constantly convex position. It is an object of our invention to provide a diaphragm-device construction which will permit long full strokes while subjecting the diaphragm walls to minimum load-reaction stress, which will give a high suction lift, which will operate efliciently both on such long full strokes and on short partial strokes, which will give long diaphragm life, and which will facilitate use of diaphragm materials which are resistant to fluids that attack rubber-like materials. It is an object of our invention to provide such a diaphragm construction in which the working portion of the diaphragm is of leather or leather-like material.

Our invention is desirably embodied in a diaphragm device in which the diaphragm has a rigid central piston portion and a surrounding annular working portion, and in accordance with our invention, the working portion is provided with opposite outwardly-convex walls, desirably shaped to semi-circular section, and such walls are mutually supported in outwardly convex position by mechanical means disposed between them. The mutual supporting means is of generally toroidal shape to lie within the similarly shaped space between the opposite diaphragm walls. It is desirably formed of spring wire-with adjacent elements thereof spaced somewhat from each other, and is most desirably formed as a helical spring with spaced convolutions and withits ends secured together to form a ring. When the support is a spring-like member, it is disposed within the annular working portion of the diaphragm, between thewalls thereof, with the convolutions of the spring slightly ispacedfrom each other and lying generally normal to the walls and radially of the diaphragm. The diaphragm is desirably mounted for double action, in a casing which provides displacement chambers on its opposite sides, formed to give but small clearance space'at the ends of the diaphragm strokes.

The mechanical'diaphragm, support can be used with any of various diaphragm materials, including flexible rubberfor rubber-like materials, synthetic plastic materials, coated fabric or leather materials, etc. But the Patented Dec. 18, 195

2 a spring-annulus supported leather diaphragm gives remarkably long life and operates effectively and efiiciently over a wide range of temperatures down to -65 F.

The accompanying drawing illustrates our invention. In such drawing, Fig. 1 is a vertical axial section through a double acting diaphragm pump embodying our invention; Fig. 2 is an enlarged partial section similar to that of Fig. 1; and Fig. 3 is a plan view of a diaphragm embodying our invention, with parts of the upper Wall broken away to show the supporting coil spring.

The pump shown in Fig. 1 comprises a front casing 10, a rear casing 12 symmetrical with the front casing, a bottom intake fitting 13 and a top discharge fitting 14, with valve plates 16 mounted between each fitting and the casing assembly. The casings 10 and 12 have-continuous annular flanges 15 between which the outer rim of the diaphragm assembly is clamped, and the casings from a front displacement space 18 and a rear displacement space 19 on opposite sides of the diaphragm assembly.

The two valve plates 16 are conveniently of identical construction,-held in place against opposite ends of the casing assembly by being clamped between it and the end fittings 13 and 14. Each valve plate 16 is punched and flanged to form two valve openings spaced to lie on opposite sides of the casing flanges 15, and each bounded by an upstanding rim 20. The rims 20 are dressed to form planar valve seats, and flap valves 21 are seated on such valve seats. The valves 21 are carried by upstanding ears pivoted on pivots 22 mounted between lugs secured to the plate 16,- and the valves are urged to closed position by the down-turned ends of springs 23 coiled about the pivot pins 22. Conveniently, the valve openings are of generally oval cross-sectional shape, and the section of Fig. 1 may be considered as taken on their minor axes.

With the valves arranged as shown, to open upwardly, the general direction of pumped flow will be upward, as

v to pump liquid out of a tank upon which the pump may be mounted. Alternatively, the valve plates 16 may be reversed, to open downward, in which case the general direction of pump flow will be downward, making the pump suitable for mounting on a tank which is to be filled and forpumping liquid from-an external supply into that tank. T he'pump may also be mounted horizontally,

' at its edge, to stifien it and to form a smoothly curved support for the inner periphery of the working annulus of the diaphragm. The piston is mounted on the operating shaft 28, which is formed in two parts, screwed together against the opposite faces of the plates 26. The :shaft 28 is mounted in bearings in the two casings and extends outward through the front casing 10, where its outer end is connected toan operating lever 24 fulcrumed on a link 29 carried by the front casing.

The two diaphragm elements 25 are symmetrical. Each has a central circular web 32, a formed annularworking portion 34, and a peripheral rim 36 which has straight edges at the'top and bottom where it approaches the flat valve plates 16. The annular Working portion 34 is desirably molded or shaped to a normal configuration which issemi-circular in cross section, with a wall arc length of substantially joined to the web 32 in a smooth curve conformingwith the flanged edges of a plate 26.- I j a a 1 The diaphragmv elementspshown were made of topgrade, chrome-tanned cowhide, but other and poorer grades of leather can also, be used. The leather may be treated to render it impervious to the liquid upon which t hew rkegithe r ,w bs' lihetwem th u m eldr b tweenit t annular portions 34 lie impppositely and, outwardly core 7 T e oppq'site V I pally supported -f ror n each other. The mechanicalsuptRhosphor-bronze'spring wire.) g a t ;The displacement spaces '18 and l9xin'theicasings i g la nu s fii nds 9f 7 i ihent :spaces thusidefinecloi'n nnicate'withtthe :1 h o gh assa Y? qfi m s s qioa an for gasoline, oil, and the'like, We'prefer to use an untreated leather which is somewhat p'erviousrto' the liquid g ascl nean, most 's o yti edsveih vet qnnsl rnofli n'g to equ i f r. oper tio at.55 .F-'

mem jlowt mp ratu e pe ation,

nmrea es l athe i y ar the ewes- Q -:,.liq,uid,,.xecipmcatidmnhihe.operatingshaftlsithrough strokes in opposite directions produces a double-acting?" As the shaft 28 moves to the right, it I carries the central piston bodily to the right and'flexe's the 7 Working annulus of thediaphragm. This increases the volume of the rear displacement space 19,-to draw liquid 7 into that space through the (lower left) valve between the" intake fitting 13 and -;,the rear :displa'cement space 19,1 51

i 'pumping efiect.

v lhei wo 's iaphra mlelemen s km as mbled with -pi 'plat '1 a d with the anaesl oftflie s ng Their fixdp itio defining an annular spa .o b t n ia y circular cross-section, and it is Qthese annular portions whichitfqrm th work ag an ul s er th 1 diaphra m sembly- Walls of t ei q r s ng an ar mechan PQI JJg' ea i d sirably a termed w e Las m y h vin onsid able re i anc o e mp ss n i metrica y .o tth n u us sec ont ut des ra ly ein ns l rbumferentia lrc h a nulu r rab y/ f cular cross section, with a somewhat smaller section di-' 'gamleterthan theintcrnal section diameter 01 the working annu l m ybe e the u der c miz e s qr c r mflex; en tially,'so that it-tends to hug the outer peripheral walls of the working annulus, or preferably is under tension, t that it tendsto hugthejnner periphery of those confining yvalls. 'We consider'it'most'desirable to 'make the mechanical'supporting means as shown, as a-simple helical 'spring 39, with straight conyoiutionstbent in a single plane. I

f tThe section'diameter of the spring is desirably about 'i to of the internal sectigndiarneter of the working-annulus, and we have found 'it mosti-suitable to use'a 1 5 spring with a section diameter about'75 of that of the yvorsing'armulus. 'The c'oilispring'is desirably made of fine spring wire with a large number of turns, andthe opposite ends oflthe spring are secured together-as by lapping one or two turns and welding or soldering the lapped turns together; as at .thespots 31.1] Alternatiyely,jt he ends may be"mechanicallyinterlocked. The complete ring should haveno :free ends liable 'tcrpuncture the diaphragm W 11s.- 7 ith a Work1 g mately 14 turns to the inch, and to use about 265 turns 'whose piston was of about 4-inch diameter.

z The wire from which the spring is madeisho uld'be of 7 17a material-not subject toia tt'ack by the fluid'ilpo'n whiei'i the diaphragm is to"wor,k,-jand-for a gasoline pump .lwe i annulus of l -inch 'section diameter, we havefound it desirable to use a coil of about .75 inch diameter wound. .rrom ;-.040 inch spring 'wire, approxiports the spring landccar'riesrithe load reaction.

jthe lstrokeTis .reyersed, the;w'all34 which hasbeen the" 1 leading wall then becnmesithe trailing wall :Sincethere vqas nofwallrevers'ion, the new-trailinglwall .is already in atraiiing arciposition-Radytd pick up theload reaction,

' with jlittleior nollost motion} 'Thcfreverse'fstrokeisefiec-" ;tiye at; once, and proceeds underithe'same load transmissionandlloadieactioni conditions in areversedirection', a

; a sfexistedl on thejorwardistroke. :In; both strokedirec IjIiODS thBjJ-QQCI i SZCfilQlled byawall'which is noti only prei .whichisin a. most 7 wentiongand on the contrary liascertain advantages. ,fIhe V L liquid iservesito lubricate the-diaphragm and ac'curnulates vtyvlthin the fworkin'g'annulus td-k'e'ep -thediaphi'agm moist i V j and-pliable during intervals of non-use. on'longdrine 7 quent pumping operations; the liquidimayth'e wink-1 50 ing annulus 'sufliciiently to provi qjag ainst the piston sideoftheworking annulus; EA: ring I v imade-as ;jset forth 'ab ove rhas an'unstressed internal di ameter of about 3 /2 inches, and was use'd in a diaphragm; f

haye'iound it suitable to use a, stainless-steel orprefer'ably r *andl l are formed Qt'o provide small clearance atitliej ends t M1134 ar curyed t'ojnatewith ni ausier'nie K iaYQIable position,.to:car1:yit.

I {semen than s d jiointsso' V helical ax! Simultaneously, the fro'nt displacement space is reduced in volume, to, dischargeiliquid I therein ;through.. t he upper right) Ivalye betweenthat, displacement 'space-l8-and; the

discharge fitting 14. A corresponding'action occurs upon the oppositestrokeof-the:shaft;28,to draw liquid into the t displacement'sQace'ISthrough its' associated intake valve, 7 and to discharg'e liquidirom the displacement space would be ,(r'evertedgfroma a forwardly convexi-forrn: .toa V 7 rconcave form: t SuclLco1lapse,is;prevented,howeven and a ,thewall is supported ;in:constant1y convexupositioniby 'the mechanical .support'pfitheinternal spring/3%). {Ihe force ;on thellealdinglzwall.;is -transmitted diametrically t across the spring section and againsteth'e' trailing wall 3 4; I t This, trailing. wall-being normally inelastic and; 7 already 7 t positioned inza trailing arc, 'betweer1. thejfixedv supportlof Q ;the;fiangesyli andethe=mOYingv support of the pistons, sup:

The use ofidiaphragm-zmaterials which arejpervious to tih11iquidtbeing ip'umped zhas' not been found harmful to the operation orlefiiciencyof a pumpt ernbodyin'g the in- V the"'diapl iragm walls hayeibeen found to give; a remarks, 1

T f -is i ii li j ixs tfi n bY s to t t me he 'fi fl ln tybbafi iaph agxpj m h S m i service hf adapted t be reciprocate'df lairially with 7 when Pum having o'ur ;mechanicalt supporting meaiisiirir;

: JYwOmR SmanbI i i '7 n betweenouterperipheralirimand Ea ulus coiiiprisingopposite'Qut-f V exible material 'defining aspa'ce' V. t a stantially circular rossgsection, and an endless heli 111g in i th n* i nac i n of s ller rsfsrespect to the rim, said annulus comprising opposite outwardly convex walls of flexible material defining a space of substantially circular cross-section, and an endless helical spring ring within said space and of smaller crosssection than said space and said spring being substantially incompressible across its section, extending circumferentially around said annulus between said annulus walls and the turns of said spring being spaced from each other and contacting each wall in a substantially circular series of points so that said ring will stretch and contract along its helical axis and will provide mutual support between the walls, said spring ring comprising a multiplicity of closely spaced turns wound from small-gauge spring wire and providing a relatively rigid support for said walls in a cross-sectional direction While freely undergoing rolling deformation as the inner and outer peripheries of said annulus are reciprocated relative to each other.

3. A pump diaphragm assembly as defined in claim 1 in which the section diameter of said helical spring is between 70% and 85% of the diameter of the circular cross-section of the space between the annulus walls.

4. A pump diaphragm assembly as defined in claim 2 in which the section diameter of said helical spring is about 75% of the diameter of the circular cross-section of the space between the annulus walls.

5. A pump diaphragm assembly for pumping oil, gasoline, hydrocarbon fuels, and the like, comprising a working annulus extending between an outer peripheral rim and a central piston adapted to be reciprocated axially with respect to the rim, said annulus comprising opposite outwardly convex walls defining a space of substantially circular cross-section, and a helical spring ring of smaller cross-section than said annulus extending circumferentially around said annulus between said annulus walls and providing mutual support therebetween during relative reciprocation of said piston, said annulus walls being composed of material which is pervious to the liquid to be pumped whereby said walls are saturated by such liquid during operation and the interfaces between said walls and spring are lubricated thereby.

6. A pump diaphragm assembly for pumping oil, gasoline, hydrocarbon fuels, and the like, comprising a working annulus extending between an outer peripheral rim and a central piston adapted to be reciprocated axially with respect to the rim, said annulus comprising opposite outwardly convex walls defining a space of substantially circular cross-section, and a helical spring ring of smaller cross-section than said annulus extending circumferentially around said annulus between said annulus walls and providing mutual support therebetween during relative reciprocation of said piston, said annulus walls being composed of material having limited permeability by the liquid being pumped, whereby on continuous operation the space between said walls becomes filled by said liquid to provide additional mutual support between said walls.

7. A pump diaphragm assembly for pumping oil, gasoline, hydrocarbon fuels, and the like, comprising a working annulus extending between an outer peripheral rim and a central piston adapted to be reciprocated axially with respect to the rim, said annulus comprising opposite outwardly convex walls defining a space of substantially circular cross-section, and a helical spring ring of smaller cross-section than said annulus extending circumferentially around said annulus between said annulus walls and providing mutual support therebetween during relative reciprocation of said piston, said annulus walls being composed of leather which is permeable by the liquid being pumped, whereby said leather walls are maintained pliant and the interfaces between said walls and spring are lubricated by such liquid.

References Cited in the file of this patent UNITED STATES PATENTS 356,997 Gil Feb.'1, 1887 846,455 Curtis Mar. 12, 1907 1,630,292 Ely May 31, 1927 2,258,009 Horton Oct. 7, 1941 2,260,205 Bayer Oct. 21, 1941 2,473,948 Harstick June 21, 1949 2,520,771 Martin Aug. 29, 1950 2,658,526 Porter Nov. 10, 1953 2,685,304 Wright Aug. 3, 1954 FOREIGN PATENTS 27,009 Great Britain Oct. 23, 18,97

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