US2745349A

US2745349A - Pumping devices

Info

Publication number: US2745349A
Application number: US266707A
Authority: US
Inventors: Tavola Bruno
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-02-05
Filing date: 1952-01-16
Publication date: 1956-05-15
Anticipated expiration: 1973-05-15

Description

May 15, 1956 B. TAVOLA 2,745,349

PUMPING DEVICES Filed Jan. 16, 1952 2 Sheets-Sheet l rfi l a, i l n ,4 f5 BY BRUNOITVCTO 25 .A 32 lbf/...rc

May 15, 1956 B. TAVOLA PUMPING DEVICES 2 Sheets-Sheet 2 Filed Jan. 16. 1952 INVENTOR. BR UNO TA vo A United States Patent PUMPING DEVICES BrunoV Tavola, Cellini, Milan, Italy Application January 16, 1952, Serial N o. 266,757 Claims priority, application Italy February 5, 1951 1s claims. (c1. 10s-37) The present invention relates to a new and improved pumping'device, and more particularly it relates to a new andl improved pumping device of the type operating according to the Sov-called alternative cycle and having at least one pressure chamber of cyclically variable cubic capacity varied by a movable member which deforms a resilient portion of the walls of said pressure chamber.

The main object of my present invention is to provide a new and improved pumping device which is not subject to the disadvantages of pumping devices of conventional construction, and in particular it is the object of the present invention to provide a new and improved pumping mechanism in which the pressure chamber forming parts are not in frictional relationship with each to others and in which an annular resilient member, and two rigid members fonn a pump pressure chamber.

Another object of this my present invention is to provide, in a new and improved pumping device designed for variable output, a special and useful inlet valve device operated by the reciprocating motion of one of the rigid members, and provided with controlling means by which the timing of the actionof said inletvalve device may be readily varied at will in respect to the phases of the cyclical contraction and expansion of the pressure chamber. An improved pumping device of the above character may be advantageously used in many practical applications, as liquid fuel injection pump for diesel engines, for example. v

A further object of my invention is to provide, in a pumping device having one or more of the above new and useful characteristics, special bearing means for supporting and guiding in a fixed path the reciprocated member or members in relation to the pump housing, without the use of frictional connections between fixed and movable parts.

A still further object of this my present invention is to provide a new and vuseful pumping device of the above character in which the uid to be pumped is fed into the pressure chamber or chambers in a new and useful manner, through leak-proof feeding chambers and passages.

A still other object of this my invention is to improve in general the construction of pumping devices having one or more of above useful characteristics, in view of making the manufacture and the assembling of same easy and inexpensive.

Other objects will be in part obvious and in part pointed out hereinafter.

With these objects in view, the present invention mainly consists in a pumping device, which comprises, a pair of spaced plate members, the plate members having oppositely arranged plate faces, at least one of the plate members being reciprocable for reducing and increasing, respectively, the distance between the plate faces, a resilient annular member having two spaced annular sealing end faces and being located between the plate mem bers with the annular sealing end faces abutting against the plate faces of the plate members, inlet and outlet valve 2,745,349 Patented May 15, 1956 means mounted on the plate members for supplying and discharging a fluid into the interior of the annular member, the inlet valve means being connected to the one plate member for movement therewith, means for reciprocating at least the one plate member whereby the resilient annular member is alternately resiliently compressed, and permitted to resiliently expand while the plate faces and the sealing faces are in permanent sealing abutment, and stationary actuating means engagingthe inlet valvemeans during reciprocating movement ofthe one plate member for operating the inlet valve means;

One form of construction designed to carry out the invention and which has been found to operate very satisfaetoriy as a liquid fuel injection pump for smallsized and fast running internal combustion engines of the diesel type is shown in the accompanying drawings, by way of exampie, and it will be'hereinafter described in detail, together with other features of the invention.

ln the drawings: i

Figure l is a vertical central sectional view of an embodiment of the fuel pump, partly in section on line 1 1 of Figure 4.`

Figures 2 and 3 are sectional views on an enlarged scale, of the pressure chamber, the movable parts being shown in different phases of their cyclical operative motion.

Figure 4 is a view, partly in elevation and partly in section on line 4 4 of Figure 1.

Figure 5 is an exploded View, partly in elevation and partly in section, of the combination of operative parts of the embodiment shown in Fig. 4.

' Figure 6 is a cross-sectional view on line 6 6 of Figure 4.

Throughout the figures, like numerals refer to like parts, and numeral 4i) in general indicates the pressure chamber. 1n the following detailed description of my invention, the assembly of the pump, the various parts thereof and the movements of the movable ones thereof will be indicated by using the words upper, lower and respectively upward and downward with respect to the positions of same in the several figures of the accompanying drawings, it being obvious that the above expressions are not limiting the field and range of the invention and in particular of the appended claims, and that in actual construction and operation any pumping device constructed according to this my invention might be designed and arranged to work in different spatial positions.-

The arrangement and cooperation of members, together with other new and useful features forming part of this invention will be apparent from the above described tigures of the accompanying drawings, wherein a preferred form of embodiment is shown in which the pump according to the invention comprises a substantially cup-shaped pump housing 10 having an inner chamber 13 and a lower opening 38, and an upper cover member 1l secured to said housing 10 by a suitable securing means, by a securing ring 12 for example, In said chamber 13, which is formed by the pump housing 10 and cover member 11, an axially movable member 14 provided with an enlarged head is arranged and supported by any suitable supporting and guiding means, and in particular by means which will be described in detail as this description proceeds.

The down-facing inner surface 16 of said cover member 11 constitutes the upper surface of the pressure chamber 40 and the 11p-facing surface 15 of the enlarged head of said movable member 14 constitutes the iower surface of same chamber.

Between the outer portions of the face 16 and of the face 15 of the movable member 14, a substantially ringshaped or annular side wall forming member 17 of re- -silient material is arranged in constant abutting relationship with

faces

15, 16. The

Atthisrpoinn' it will be apparent to those skilled in the y art that-'I provided, in" a pumping'device operating according'to'the alternative cycle, a pressure chamber the cubic capacity of whichmayjbe alternately increased and reduced, by increasing' 'and reducing, respectively, the spacing of `plate faces 15'and y'16 of the

rigid members

11 and 14. 'Il'lie walls ofthe'pressure chamber are formed by acombination of' resilient and rigid members. In fact,

the upper and 'lower annular'sealing faces of the annular resilient member`17`made of resilient material are permanently abutting the outer portions of the' faces 15, l16 of cover member 11 and of movable member 14, respectively, while no relativeV motion is imparted to ring member 17 with respect to the coverY member 11 and the movable member 14.

It twill be readily understood that an absolute sealing of said pressure chamber m'ay'easily be obtained in view of the fact that a complete seal may be easily obtained between theV contacting surface portions of the resilient ring member 17 and the faces 16' and 15 of cover member and of movable member, respectively. The permanent sealing abutment may be attainedsimply by suitably dimensioning member 17'Y so Vthat'its axial thickness in normal condition wouldl be larger than the largest spacing between

faces

16 and 15 which is obtained during the regular operations of the device; Means may be provided too for assuring the sealing engagement such as a suitable adhesive.

Further, from the above and from a consideration of Figures 2 and 3jit will' be understood that I provided a new and useful construction of a pressure chamber the cubic capacity of which may be reduced at a greater extent than corresponding, to the' bore to stroke ratio owing to the factfthat the axial' compression of said resilient lring 1-7 Vproduces an inwardly'dir'ected' bulking of the inner'cylindricalsurfacefthereof. Y

It will still further be 'apparent that the absoluteleakproot'nessA ofV pressure chambers of pumping devices according to this myinvenn'on vpermits the design of pumps whoses'troke may be smallerthan the diameter of the pressure chambers; for example, a form of embodiment of myeinvention, intendedy toV operate as an injection pump forV small yand fast running'engines, has been found to operate very satisfactorily by Vimparting to the reciprocated member 14 a strokefrom %00to2/00 of ank inch. The useof'such small stroke'values obviously oters very remarkable advantages, 'a very low linear speed value even though the'pump is driven` at'-very high speed, small wear of movable parts, reduction of the driving power, fast action of the pumping phase, exact timing, and so on.v

In. the illustratedy embodiment the pumping device has a substantially conventional outlet checkvalve 18 including a ball 19 urged by al spring 20'V against a suitable seat. In the illustrated embodiment the inlet valve means comprises a frusto conical seat 21 drilled in the center of plateface of the movable member 14, and cooperating with a poppet valve 22, made integral with a stem 23 which is slidably supported for axial movement in movable member 14, a coil spring 27 being providedfor urging said poppet valve 22 against its seat 21. A stop member 24 connected to the xed Vstructure of the pumping device isY provided for limiting the downward motion of poppet valver21 in respect to said tixed structure, the stopl memagees@ ber being so positioned that it stops the downward motion of the inlet' valve` means -22-23, which moves together with said Amovable member 14 during the downstroke thereof, before that said movable member reaches to its lowermost position. Consequently the stop member constitutes an actuating means for the 'inlet valve. During the down stroke of movable member 14 the seat 21 of said poppetvalve 22: detaches'itself from-said valve 22, opening the same'. Likewise, during the up-stroke of said movable member, at a certainposition the seat 21.

in movable member 14 reaches its contacting position with said valve 22, closing'the same. It is to Abe p'ointed out that inA my described new inlet valve device the operation of the valve is carried out by moving the seat in respect to the valve.\

From the above it will be apparent to those skilled in the art that the actual operative cubic capacity of the pumping device does not depend o n the whole stroke but on the stroke portion 'between the lowermost position andV the position in whichthe inlet `valve closes. Having this operative featurein A'mind,it willlbe readily understood that by providing suitable means for timing the actuation ofthe inletvalve thelactual operative cubic vcapacityvof the pumping device might be varied at will. For this purpose Va cam-shaped portion 24in a transversev shaft 25vis provided as stop member for actuating,

the inlet`valve 22,; lthe shaft.V 25 pressing jdiametrally through both said movable member, 14 and said pump'k housing I0, and rotatably supported by the latter, elongated transverse passages 39 being'. provided in said mov- 14, maybe varied lat willwithin the desired rangeofoperation. The radii of said cam-shaped portion 24 might be easily designed to* shift the actuallowermost positionk of said valve' up to or above the'uppermost position whichl it would reach in contacting relationship with itsfseat, if

a control' range extending yup to zero out-put is desired.

In a pumping deviceY according to this my invention, any suitable driving means'rmaybe provided for reciprocating kthe movableV member 1'4. ln-the preferred form of embodiment shownthe movable'fmemb'er 14 y,is provided with a Vthrea'ddly. .connected lower portion 28K extending out of pump housingl'tl through said bottom opening 38, said lower'poi'tion beingroperatedbya cam 29. Of course, other vdrive means might be substituted according to the different specific requirementsof operation: for pumping vkdevicesinwhich a brief and exactly timed pumping phase is not'required, afconventional crank Vand connecting rod device, an eccentrical driving wheel,

or a slot-and-crank device may be provided.

In the case that a cam for an operatively equivalent device is provided for reciprocating the movable member, the backward stroke of said vmember might be obtained by using the same resilient'substantially ring-shaped member 17, owing to its resiliency.L The use of va more etcient`l spring means is however deemed preferable, ini particular incase of 'embodiment of this invention designed toA run at higher speed.v As` showninthe accompanying drawing,

preferably I provide a vcoil,jsp1ing33 for .co-operation' with camr29., The coil spring isarranged around said movable member 14and its ends abut 'on an in-turned ilange forming ringirnember'Srxedly connected to the pump housing (in particular, 'tightly closed between a step 41 provided insaidhousing'lil--andthe lower edge' 42 of cover: member 11,;see;.Figure:f5)fy and onan out-turnedange formingringmember ST, tixedly,Y connected to sadv movable member 14.-(in particular-,tightly closedbetweenY a step 43 provided in said vmovable member 14 Vand the upper edge 44 of Vthe lower portion 28 of the movable assembly, see Figure 5). It will be apparent that said spring 33 urges the movable

assembly comprising members

14 and 28 in downward direction.

Further, any suitable guiding means may be used for Vguiding the movable member along its xed path in axial relationship with the pressure chamber, slide bars or other sliding devices, for example, and a suitable means may be provided too in bottom opening 38 for sealing the inner chamber 13, if desired. The uid to be pumped is fed under a certain pressure into said inner chamber 13 through an inlet passage 31, from any suitable source of pressurized uid (not shown).

For carrying out said simple system for feeding the pressure chamber with pressurized uid fed into said inner chamber 13 of the pump housing, l provide the movable member 14 with passages 32 through which said inner chamber 13 communicates with the valve opening encircled by seat 21 of poppet valve, through which said inner chamber 13 communicateswith the pressure chamber 40,

provided that seat 21 is detached from poppet valve 22.

A second substantially ring-shaped member made of resilient material is arranged in said bottom opening 3S of pump housing and iixedly connected at its outer edge to the wall of said opening and at its inner edge to the lower portion of the movable assembly which is axially reciprocated through said bottom opening.

in the form of embodiment shown in the accompanying drawings, the sealing of the annular space comprised between the inner surface of opening 38 and the outer surface of lower portion 28 of the movable elements is sealed by a at ring-shaped member 30 of resilient material, the outer edge of which is inserted into an annular groove provided in said inner surface of opening 38 and whose inner edge of which is inserted into an annular groove 46 f provided in said lower portion 28 of the movable elements (Figure 5), the portionof said ring-shaped member 30 between said outer and inner inserted portions being wide enough to allow the bending of said resilient member as necessary in view of the reciprocating motion of said movable assembly in respect to said pump housing. Consequently chamber 13 is reliably sealed and the movable elements centered in opening 38. The resilient ring member 17 acts as an efficient centering means of same mov- Y able elements, in respect to the upper portion thereof.

The said second resilient ring-shaped member 30 may be made of natural rubber, synthetic rubber, resilient plastic, and so on, and also it might be made by a resilient thin metallic sheet, which may be corrugated.

The operation of a pumping device constructed as above described and shown in the accompanying drawings will be apparent from the following description, referring in particular 'to Figures 2 and 3.

VProvided that ca m 29 is properly connected in the necessary timed relationship with a rotating part of the internal combustion engine the injector of which is to be fed by the pump, and provided that the inlet passage 31 is connected to a suitable supply means of pressurized liquid fuel, the inner chamber 13 will be full of pressurized liquid. Supposing now the movable member 14 to be at its lowermost position (Figures l and 4), the poppet valve 22 at its lowermost position permitted by theabutment of the lower end of its stem 23 onV cam portion 24 of shaft 25, the valve member 22 is detached from its seat 21, thus allowing free admission of fuel from chamber 13 and through passages 32 into pressure chamber 49, which is filled while the outlet ball valve 19 is kept in closed position by spring 26. By operation of cam 29, the movable rigid member 14 then starts on its tip-stroke motion, in direction A, and lthe spacing of movable face 15 from face 11S-will progressively decrease, while the side wall formed by'inner surfaces of the substantially annular resilient member 17 will be subject to progressive inward bulging. TheV volume of pressure chamber 40 is progressively reduced but, owing to the applying current knowledge.

fact that until seat 21 engages valve 22 pressure chamber 40 is not separated from feeding chamber 13, the excess fuel due to the diminishing capacity of pressurey chamber 40 is back-fed into said feeding chamber 13 in direction B (Figure 2).

As the upward motion of movable member 14 proceeds, at a certain point of said motion seat 21 engages'poppet yalve 22, effecting the separation of pressure chamber 40 from feeding chamber 13. At this point the actual operative pumping phase starts, and any subsequent reduction of cubic capacity of said chamber 40 causes the discharge of the liquid fuel in direction C through outlet valve 18, the ball 19 of which is forced open by the pressure until said movable member 14 reaches its uppermost position. It will be apparent from above that the amount of liquid Vdelivered at any cycle of operation of the pump may be varied by rotating cam portion 24, i.`e. byvarying the position of said contacting position of seat 21 with valve 22 in respect to the amplitude of up-stroke of movable member 14. The later the contact occurs during the upstroke motion the smaller is the cyclical out-put.

In the form of embodiment shown, the pumping device according to this my invention is designed chiey for injecting fuel in a combustion chamber of a single cylinder small engine; however, it will be apparent the features above described or their equivalents may advantageously be applied to the construction of pumps for multi-cylinder engines, and for` any other field of application in which a pumping device is necessary. Further, a pumping device of the character described or its equivalent may usefully be provided with auxiliary devices and features, by applying current knowledge in the art; for example, the pump shown in the accompanying drawings is provided with a discharge'passage 34 normally kept close by a needle valve 35 for a convenient time to time vent air from pressure chamber 40.

It is to be further understood that the device above described may be further improved both in its structure and in its operation, by combining the above disclosed features with other devices, features and methods that those skilled in the art may readily apply and use by Consequently, While I have herein described a preferred single embodiment of my invention, the invention is not intended to be limited thereto, and other embodiments and modifications incorporating one or more of any advantageous features and of any novel functions of the form herein disclosed and embraced by the appended claims will be apparent to those skilled in the art.

Having thus described the invention, what I claim as new and desire to have protected by Letters Patent is:

l. In a pumping device a first rigid member, having a iirst face, a second rigid member in variably spaced relationship with said iirst rigid member and having Va second face opposite said first face, a substantially ringshaped member, made of resilient material, in abutting relationship with both said faces and having a cylindrical inner surface defining with said faces a pressure chamber, driving means for reciprocating one of said rigid members in respect to other of said rigid members as to vary the spaced relationship thereof Within the limits allowed by the expansion and compression of said resilient substantially ring-shaped member abutting thereon, a valve seat forming inlet opening being formed in said face of said one of said rigid members, a valve movably supported by said one of said rigid members so as to cooperate with said seat for closing said inlet opening, 'means for detaching said valve from said seat in timed relationship with the cycle of operation of the device, said means comprising a stop member connected to the other of said rigid members and arranged to actuate said valve to detach itself from said seat as said one said rigid member approaches to its most spaced position from the other said rigid member, and outlet check valve means mounted on the other of said rigid members and communicating with said pressure chamber.

I`seat for closing rlttnship wenn, .rigid ,member endinvng, a

second face opposite said first face, a substantially ,shapedrmemben made ofA resilentmaterial, in abutting relationship wthrboth seid faces and, hai/ inea Cylindriu1eal'innenSuteeetdening.uithsad taees a pressure Chamhet,driving` meansfol: reeiprofeatingione of Seid Iia members in respect v to other of s a i d rigidmembersasrto ,ya ry the spaced re1ationship thereof within the limits ,ilowedbnthe expansion, andempressien of Said @Sil-t tent substantially Vri.ns-ShapedY ,memberyebutting thereon, .a .yalye seatrforrming inlet openingbeing formed in ,said

faeenffsaid one ofvsaiiilv rigid members, a valvemevably Y.

tion of said stop member in respect to the dilferentrelativepositionsof said rigid members in yariably spaced v relationship, and outlet check valve means mountedon the other -of `sa id rigid members and communicating with said pressure chamber.A 4 v 3. ,A pumping device particularly designed as liquid fuelinjection pump, comprising, in combination, a pump housing havin'g'an inner Achamber provided with an inner top surface, with alower opening 'and with an inlet opening for connection with apressurized fuel supply means, a movable member movably supported into said charnber in axial relationshipwith saidinnertopsurface and downwardly extended through said lower openingand having anjupper surface in opposed and spaced relation to Asaidinner top lsurfac`e, said movable member being .formed with a valve V seat formingopening in said upper surface, avalve movably supported in said movably s upportedmember and cooperatingwith saidvalveseat for closing said opening, `said movable member being formed withpassage means connecting said openingto the lower portion of said inner chamber, driving means for reciprocating said movably supported member in respect to said ,pump housing,a first ysubstantially ring-shaped member made of Yresilient material V and arranged between said inner top surface and said uppersurface and in constant Yabutting relationshipwith the outer portions thereof, a

,Second substantially ring-,shaped member of resilient ma- V teriaL having its outer edge xedly connected to inner edge of lower opening and its inner edge tixedly connectedto said Amovably suported member for movably supporting the same in cooperation 'with said first substantially ringishaped member andfor sealing said inner opening for connection witha pressurized fuel supply means, a movable member movably supported into said chamber in ax'i'al relationship with saidinner top surface and downwardly extended through said lowerV opening and having an upper surface in opposed and'spaced'rella'tionlto' said 'inner top surface, 'vsaidrn'ova'ble member being foriied"withY a"valve' seat forming opening in said upper sufacefajalve 'movably supported ins'id ably ni'en'ib'erfandt cooperating' between Seid. 5119er "feti Srfe @iid Seid "iPPlef ffa and in constant relationship'with 'the c'm'ter'po'r-` there@ edge fixedly connected tofsaid movably.` supported meinber for movably supporting dthe in cotipelratian"with member and `for sealing said inner chamber, a stopl member "turnably mounted in said'pnmp housing; andhavin'g a turnable cani-shaped a movablemember movably supported'into said chamber in axial Arelationship with said inner top surface and downwardly extended throughbsaidlower opening and having an 'upper surface in opposedand. spaced relation to said inner top su rface, saidmovable member being formed Witha ,valve Seetrmine epegvnrsad upper suffe?? .anda/i111. atretlsversetpessese, a Pepper valve having e. 'steen,slidablyeurpened insaid movably Suppefted memberand cooperating kwith said valve seat for closingsaid premies, .Saidmovable member. being formed with Passage Y means connecting said openngto the lower portion of said inner chamber, camftype driving means for impartngen-upzst1ekemet0n and spring means for imparting a downstroke motion tosaid movably supported member, a

tiret silbstentially ring-Shaped member. made of resilient material and arranged between said innerjtop'surface andV said upper surface and in constant abutting relationship ,withtheouter portons'tbe'reof, a second substantially ringshaped member of resilient material having its outeredge lixedly connected to inner edge of said lower opening andY its mneredge fixedly connected to said movably supported member` forrmovably supporting the same in cooperation withsaid4 first substantiallyV ring-shaped member and for sealing said inner chamber, a shaft rotatively supported by said pumphousing and transverselyr passing through the latter andtbrough said transverse passage in said `movably v supported member, and havinga'portion extending outside lsaid housing for manual operation,` and aGaIn-shaped portion positloned under theilower end 'of's'aidstem Iand aetingras adjustable stopfmeans to stop the downward Y motion of said valve during downward strokes of said movably snpported member' as saidl movably supported member approaches its lowerrnost position, for'causing said valve seat to be displaced from said valve.

6, In a pump, in combination, a pair of spaced plate members, saidk plate members having oppositely arranged plate faces, atleast one of said plate members being recip-V rocable for reducing and increasing, respectively, the dis-V tance' between saidplate' faces ;V a 'resilient' annular member n having twofspaced annular' sealing end ,faces and Vbeing located betweensaid'lplate members with said` annular Lsealing'endl faces abuttingagainst vsaid plate faces 'of/said?V 'I plate members; inletvndfoutlet valve means'mounted on "id platefmer'rliers frjsuppiying 1and disharging anni@ =70 "mto'l the interior-of saidjannularmember, said' inlet valve A econdlsnbvstantially ring-'shaped ,r'nerril'ae'nv Y et ,resilient materiel beviaeits enter edge, `xedly' eenf necteclto `inner edge u of said rlovtjer opening and its 'irfrie'rV turning said stop vmemberandsaid cam-shaped 'porfaces are in permanent sealing abutment; and stationary actuating means engaging said inlet valve means during reciprocating movement of said one plate member for operating said inlet valve means.

7. In a pump, in combination, a pair of spaced plate members, said plate members having oppositely arranged plate faces, at least one of said plate members being reciprocable for reducing and increasing, respectively, the distance between said plate faces; a resilient annular member having two spaced annular sealing end faces and being located between said plate members with said annular sealing end faces abutting against said plate faces of said plate members; inlet and outlet valve means mounted on said plate members for supplying and discharging a lluid into the interior of said annular member, said inlet valve means being connected to said one plate member. for movement therewith; means for reciprocating at least said one plate member whereby said resilient annular member is alternately resiliently compressed, and permitted to resiliently expand while said plate faces and said sealing faces are in permanent sealing abutment; and stationary actuating means engaging said inlet valve means during reciprocating movement of said one plate member for operating said inlet valve means, said actuating means being adjustable for determining the timing of operation of said inlet valve means with respect to the reciprocating movement of said one plate member.

8. In a pump, in combination, a pair of spaced plate members, said plate members having oppositely arranged parallel plate faces, at least one of said plate members being reciprocable for reducing and increasing, respectively, the distance between said plate faces; a resilient annular member having two spaced parallel annular sealing end faces and being located between said plate members with said annular sealing end faces abutting against said plate faces of said plate members; inlet and outlet valve means mounted on said plate members for supplying and discharging a fluid into the interior of said annular member, said inlet valve means being connected to said one plate member for movement therewith; means for reciprocating at least said one plate member whereby said resilient annular member is alternately resiliently compressed, and permitted to resiliently expand while said plate faces and said sealing faces are in permanent sealing abutment; and stationary actuating means including a rotary cam means engaging said inlet valve means during reciprocating movement of said one plate member for operating said inlet valve means, the timing of the engagement of said inlet valve means by said cam means being adjustable by rotation of said cam means.

9. An arrangement as claimed in claim 8 and including manually operated means for rotating said cam means.

10. An arrangement as claimed in claim 8 wherein said outlet valve means includes resilient means for automatic closure of said outlet valve means, said outlet valve means being adapted to be opened against the action of said resilient means by the fluid pressure produced by the reciprocation of said one plate member.

l1. ln a pump, in combination, a pair of spaced plate members, said plate members having oppositely arranged parallel plate faces, at least one of said plate members being reciprocable for reducing and increasing, respectively, the distance between said plate faces; a resilient annular member having two spaced parallel annular sealing end faces and being located between said plate members with said annular sealing end faces abutting against said plate faces of said plate members; inlet and outlet valve means mounted on said plate members for supplying and discharging a uid into the interior of said annular member, said inlet valve means being connected to said one plate member for movement therewith; spring means urging said one plate member away from said other plate member; and a rotary cam member engaging said one plate member for moving said one plate member toward the' other of said plate members against the action" of said spring means whereby said one plate member is reciprocated and said resilient annular member is alternately resiliently compressed, and permitted to resiliently expand while said plate faces and said sealingrfaces are in permanentsealing abutment;rand stationary actuatingV means engaging said inlet valve means during reciprocating movement of said one plate member for operating said inlet valve means.

l2. A pump comprising, in combination, a casing having an inlet; a fixed plate member secured to said casing, and dening with the same a chamber communicating with the outside through said inlet in said casing; a movable plate member reciprocably mounted in said chamber, said plate members having oppositely arranged parallel faces, the distance between `said faces being reduced and increased, respectively, during reciprocation of said movable plate member, said movable plate member being formed with conduit means connecting said chamber in said casing with a central portion of said face of said movable plate member; inlet valve means located in said central portion of said face of said movable plate member communicating with said conduit means; an annular spring loaded check valve means in a central portion of said fixed plate member; an annular resilient member having two spaced parallel annular sealing faces and being located between said plate members with said annular sealing faces abutting against said faces of said plate members and surrounding said central portions; and means for reciprocating said movable plate member whereby said resilient annular member is alternately resiliently compressed and permitted to resiliently expand during reciprocation of said movable member with said faces in permanent sealing abutment.

13. A pump comprising, in combination, a casing having an inlet; a fixed plate member secured to said casing, and defining with the same a chamber communicating with the outside through said inlet in said casing; a movable plate member reciprocably mounted in said chamber, said plate members having oppositely arranged parallel faces, the distance between said faces being reduced and increased, respectively, during reciprocation of said movable plate member, said movable plate member being formed with conduit means connecting said chamber in said casing with a central portion of said face of said movable plate member; inlet valve means located in said central portion of said face of said movable plate member communicating with said conduit means; an annular spring loaded check valve means-in a central portion of said fixed plate member; an annular resilient member having two spaced parallel annular sealing faces and being located between said plate members with said annular sealt ing faces abutting against said faces of said plate members and surrounding said central portions; means for reciprocating said movable plate member whereby said resilient annular member is alternately resiliently compressed and permitted to resiliently expand during reciprocation of said movable member with said faces in permanent seaiing abutment; and actuating means mounted in said casing and connected to said lixed plate member and engaging said inlet valve means during reciprocating movement of said movable plate member for operating said inlet Valve means.

14. A pump comprising, in combination, a casing having an inlet; a fixed plate member secured to said casing, and defining 'with the same a chamber communicating with the outside through said inlet in said casing; a movable plate member reciprocably mounted in said chamber, said plate members having oppositely arranged parallel faces, the distance between said faces being reduced and increased, respectively, during reciprocation of said movable plate member, said movable plate member being formed with conduit means connecting said chamber in said casing with a central portion of said face of said movable plate member; inlet valve means located in said 25e-sags@ centran patienter said-fees Tof#'saiclfn'icvableplate mene spaltigleaselfclieekV valve v'Inemsin-a centrar 'portierid of said-'liked plate member; an annularV resilient' meiictb'erV c having -twciV spaedparall'el annular sealing face's'and bef' ing locatedlbetweensaidplate membersy with said annular sealing; faees abuttingragain'stsaid' faces-of said lplate-V members :andy 'surrounding said Centralf portions; 'meansl for reciprocatngsad movable plate memb'erwhereby saidresilient annular member vis alternately resiliently compressed and permittedvto resiliently expand during reeiprocation of said'rmovable -member with said facesin permanent sealing abutmentg arlda manually'operated rotary lactuating canimeansmounted nsaid casing'tur'n-A able about an axis transverse Itothe'direction of reciprocation of saidvmovable plate member, said rotary camA means engagingl said inlet valvemean's-during reeiproeation of said movable plate member for operating said inlet valvemeans, the timing offtheoperation` of saidv inlet valve means being determined bythe position of Said `rotary camA means.

l5. In a pump, in combinati'n, a casing'having an inlet; a fixed plate membersecured'it'o said casing `and denug with the same a chamber communicating-withfthe outsidethrough said inlet in said casing; afmovable plate mem-v ber located in said Chamber, said 'plate members having' oppositely arranged parallel plate faces, said movable plate member and said `easingbeing formed with op- V12 positelyarrage'd'lannular grooves; a resilinzl'tA supportingV ring' meansilcated' between saidimova'ble plate member and said'casingy and'iprojecting intojsaid'annulr grooves' Vof said members for l'novably supporting said movable plate member; a resilient annular member. lo'catedbetween said platel membersf andV having` annular sealing.; faces abuttingn against s'aidfv` plate members; inlet and outlet valvejmeans mounted on said plate members for supplying and diseh'argin'g a'uidiintothe interior'of said annular member, saidl nletfvalvemeans being connected to'said. one plate kmember for' movement'therewith; means for reciprocating,said'movable plate member whereby said annular member'is' alternately resiliently compressed and' permitted' toiexpand vresiliently; and stationary actuating. means'engagin'g `said inlet valve means during reciprocatingmovement'of said.movable plate Vmemberl for opet ingcsaid `inlet valve means.

ReferencesCited'inthe'le" of 'this patentY i UNITED STATES vPATENTS