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Publication numberUS603805 A
Publication typeGrant
Publication dateMay 10, 1898
Filing dateMay 22, 1897
Publication numberUS 603805 A, US 603805A, US-A-603805, US603805 A, US603805A
InventorsWilliam M. Wood
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Jeanie b
US 603805 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

(No Model.) I

W. M. WOOD, Deed. J. B. Woon, Administratrix. ROTARY PUMP.





SPECIFICATION forming part of Letters Patent No. eo3,8o5, dated May 1o, 189e. Application filed May 22, 1897,` Serial No. 637,710. (No model.)

To ald whom it may concern:

Be it known that I, WILLIAM M. WOOD, of Boston, county of Suolk, and State of Massachusetts, have invented an Improvement in Rotary Pumps, of which `the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

The present invention relates to a rotary pump of that class in which a gang of plungers are caused to reciprocate in suitable chambers or cylinders by the eccentricity of a driving and stationary member and'is embodied in a novel construction and arrangement whereby great efficiency is obtained in a machine of small compass, the construction and arrangement of which are such that the machine can be inexpensively constructed.

The pump embodying the invention is mainly intended for use as a gas-compressor in refrigerating systems, although it is equally well adapted for other purposessuch, for example, as compressing air for compressedair motors, etc.

yThe machine embodying the invention comprises a frame or casing substantially cylindrical in shape and having a series of radial plungerchambers surrounding a central bore or opening which is arranged' to be substantially gas-tight and constitutes the inlet-chamber of the pump. Each chamber communicates at its outer end through'a suitable valve with an annular space formed in the said casing, which constitutes the outlet-chamber, and is provided with outlet-openings adapted to communicate with the receiver for the compressed i'luid. Each of the radial plungerchambers contains a plunger adapted to cooperate with an eccentric, which is mounted on a shaft coaxial with the cylindrical chamber, so that in the rotation of the said shaft the plungers are reciprocated in their respective chambers, each plunger being provided with a valve which is adapted to open as the plunger moves outward with relation to its chamber-- e. makes its backward stroke toward the middle of the casing*and to close as the plunger moves inward in making its forward or working stroke, so that the gas in the interior of the casing iows into the several pluIIger-chambers as the respective plungers move out, and is then compressed and forcedinto the annular outlet-chamber aforesaid during the inward movement of the said plungers. To reduce the friction, the eccentric is surrounded by a loose or floating ring, between which and the eccentric are interposed a number of rollers or similar antifriction devices, and the plungers are caused to cooperate with said ring, each plunger having a shoe connected therewith adapted to be held against the surface of the ring by means of shoulders extending over the same, so that while the said shoes are capable of moving along the surface of the said ring they are held against the said surface as it approaches and recedes from the mouths of the respective chambers in the rotation of the shaft which carries the eccentric. With this construction the ring will not be caused to rotate With the eccentric,while being carried thereby with a revolving movement around the axis of the shaft, and the travel of the shoes Aalong the surface thereof will be only sufficient tocompensate for the eccentricity, there being, therefore, a comparatively small amount of friction developed in these parts in the operation of themachine, which consequently is capable of operating at a high speed and compressing to a high degree of pressure. y

The invention further relates to certain novel details of construction and arrangeintegral therewith and containing a central opening or inlet-chamber a, shownas provided with an inlet-opening a2, into which is screwed a pipe a3, leading from the supply of gas or fluid which is to be compressed. Surrounding the said chamber near the outer pe-. .riphery of the casing is an annular chamber b, constituting the outlet-chamber and having one or more outlet-pipes b2, adapted to communicate with the receiver for the compressed gas.

Extending from the chamber a to the chamber o are the plunger chambers or cylinders c, extending radially through the casing A, it being practicable, as shown, to bore the said chambers through from the outer wall of the casing, each chamber then being provided with a bushing c2, carefully finished, to coperate with the plunger d, which is movable therein, as will be described. Each of the chambers c therefore affords a communicating passage fromthe chamber a tothe chamber o, the gas passing'through an opening in the plunger, controlled by a valve d2, during l[he outward movement of said plunger with relation to its chamber, and then during the inward movement thereof being forced into the chamber b through a valve c3, which closes when theplunger begins its outward stroke, the closing being effected by the pressure in the chamber o, aided, if necessary, by the stress of a spring c4,with which it is preferably provided.

The valve c3 is shown as cooperating with an annular valve-seat c5, formed in the tubular bushing c2, and just above the said valve"- seat an annular space c( is formed, said an'- nular space communicating with the chamber bby means of one or more openings c7, through l which the gas 1s forced into said chamber, it

being obvious that the gas can pass through said chamber, around the plunger-chambers',

by means of the annular space c6 aforesaidf The bushing c2 is shown as provided with a shoulder 02, cooperating with a correspondingshoulder in the bore in the main casing, l

and the said bushing is kept in place by means of a bonnet e8, which is shown as provided with a seat o9 for the valve-spring c4, and is secured to the casing bymeans of bolts or cap-screws 010. 1

This construction is very simple and has the advantage, moreover, of rendering all parts of the machine easily accessible, it be'- ing obvious that if it is desired to get at the interior of any of the chambers it is neces'- sary only to remove the bonnet cs, when the valve c3 and bushing c2 may also be removed, since the bonnet constitutes a fastening device,whereby all the parts are retained afterbeing assembled.

To properly pack the plunger-chamber and prevent the gas from escaping around the bonnet, the bore in the casing is shown as slightly larger at its outer end than along the body of the same, while the upper portion of the bushing is cut away, as shown at cl2, thus forming an-annular recess at the line of junction between the bore and bushing, in which is laid a ring cl3 of soft metal, adapted to be engaged on top by a tongue c1'4 along the face of the bonnet o8, thus constituting a practically gas-tight joint. y

The plungers d are shown as consisting of substantially cylindrical shells, having at the plunger.

their inner ends thimbles cl3, adapted to be screwed into the ends thereof and provided with flanges d4, overlying a packing-ring d5, supported on a shoulder d6 at the outside of Each of the said thimbles is provided with an opening surrounded by a valve-seat d?, with which cooperates the valve d2, above named, the said valve being shown as provided with a stern d20, supported in a i bridge-piece dm, and adapted to be seated by means of a spring (122, interposed between said bridge-piece and a nut or enlargement 128 at the end of the stem. To produce the reciprocating movement of said plungers, they are adapted .to cooperate with an eccentric c2 on a driving-shaft e, which is mounted in bearings concentric with the axis of the cylinder, so that in the rotation of said shaft the periphery of the eccentric approaches and recedes from the wall of the chamber a.

To connect the plungers d with the periphery yof the eccentric which is controlled by the driving-shaft e, each plunger is provided with a shoe cls, pivotally connect-ed to said plunger, the said shoe being shown as provided with a lug dg, through which extends a cross-piece d10 in the interior of the plunger.

In order to reduc-e the friction, the shoes d8,

vinstead of cooperating directly with the eccentric c2, which would necessitate a constant travel of said eccentric along the surface of the shoes at whatever speed the shaft was operated, are caused to cooperate directly with a lioating ring g, surrounding the eccentric e2, so that the outer periphery of said ring will follow the movement of the periphery'of the eccentric, and between the said ring and the eccentric are interposed antifriction devices or rollers f, so that the eccentric can travel within the ring with but 'slight friction, While the ring, by reason of its non-rotation, has but slight sliding movement with relation to the shoes d8. To properly cooperate with the shoes d8, the said ring is shown as provided along its periphery with undercut shoulders g2, overlying and engaging a portion of the shoes d8, so that the shoes, while free to travel valong the periphery of the ring, are constantly held against the same, whereby each plunger in turn will be forced forward into its cylinder and drawn backward therein as the periphery of the ring approaches and recedes from the wall of the inner chamber. The said ring` is shown as comprising two sections gg, each of which has one of the undercut shoulders g2 formed therein, so that the two sections can be separated for the insertion of the shoes, and then drawn together, as shown, and secured by the bolts g4, so that the shoes are retained in position by said shoulders, the ring then practically having an undercut groove along its periphery adapted to retain the shoes.

In'the operation of the machine it will be seen that the ring being acted upon by the shoes against the pressure of the gas will remain substantially balanced Vor stationary,



while the shoes will simply travel back and forth along the periphery thereof to a slight extent to compensate for the eccentricity, the friction, therefore, being but slight and nearly all taken up by the antifriction devices. possible,however, for the ring to rotate or turn upon its own central axis,so that it mayremain without sliding on the shoe of that one of the plungers which at any moment is meeting the greatest resistance or back pressure, and the slight compensating sliding movementthus takes place mainly between the ring and the shoes of the plungers against which the pressure is least.

The shaft e is shown as provided with a bearing e3 in one side of the casin g A, the said bearing comprising an opening through the main wall of the said casing and an extension therefrom containing packing material e4, which surrounds the shaft and is held in position by means of a locking bearing member e5, fitting the shaft and extending into the extension e3 against the packing material. The extension e3 is shown as provided with an oil-hole e30 for the purpose of keeping the4 said shaft lubricated. To further assist in packing the shaft-bearings to prevent the escape of gas from the chamber a, the opposite end of said shaft is shown as provided with a suitable bearing or two bearings, the bearing e6 being shown as formed in a bonnetpiece e7, adapted to iit the open side of the casing and close the chamber a, the said bon, net-piece being held in place by a supplemental bonnet-piece e8, secured to the wall of the casing A by means of cap screws e9. Within the bearing e there is packing material 660, so as to form a substantially gas-tight joint, it being obvious, however, that such gas as may leak through or escape will enter the chamber @80, formed by the bonnet-piece es. Where the shaft passes through the said chamber, it is provided with packing material esl and a locking bearing member es?, and the chamber e30 is'shown as provided with an annular opening eSS for oil, it being intended to keep the said chamber substantially full of oil, which will then work in along the shaft to keep the bearings lubricated. As stated,.

such gas as escapes from the chamber a at this end of the shaft will enter the chamber 680, and in order that the pressure of such gas may assist in packing the shaft the end of said shaft which passes through the bearingpiece ce2 is of smaller diameter than the main portion of the shaft, so that a shoulder el@ is formed thereon, it being obvious, therefore, that the gas in the oil-chamber eso will exert an unbalanced pressure on the said shoulder, tending to force the said shaft to the right, Fig. 2. At the opposite end of the said shaft, Where it lies adjacent to the body of the casing A, it is shown as provided with an enlargement @12, having an annular beveled surface adapted to cooperate with a countersunk beveled opening in the inner wall of the ,casing A, it being obvious that the pressure upon Itisl the shoulder elo will tend to force the said enlargement closely into contact with the countersunk portions of the openings, so as to effectually close that end of the shaft and prevent leakage of gas at that side.

In the form of pump herein shown the pressure in the chamber a is slight during the operation of the pump, it being obvious, however, that when the pump Vis stopped the pressure will be equalized in the chambers a and b and will then tend to leak through the shaft-bearings, while the construction above described will tend to prevent loss by leakage. Manifest-ly, however, the inlet and outlet chambers might be reversed by a proper arrangement of the valves, in which case the chamber a would become the high-pressure chamber, and the novel packing means above described are designed with a view to such construction. It may be stated in this connection that while the chambers a and b have been referred to, respectively, as the inlet and outlet chambers it is not intended to limit the invention in this respect, as it would only involve reversing the valves to reverse the functions of the chambers, without departing in any sense from theconstruction which embodies the invention.

The construction hereinbefore described of the casing is such that it is a comparatively simple matter to form a water-jacket for cooling the plunger-cylinders, the said waterjacket being obtained, as shown,by forming an annular groove 7?. in the outer wall of the casing, at each side thereof, the said grooves being connected across between the plungercylinders by means of transverse openings h2, while the grooves and chambers are closed to form a receiving-chamber for Coldwater by ,K means of the annular bands h5, extending along the said grooves in the walls of the cylindrical casing, and are shown as secured in position by means of bolts h4 and nuts h5, the said bolts extending across through the transverse vopenings h2, as best shown in Fig. l.`



The inlet and outlet to this space may be loessary that the Water should be admitted and allowed to How out before ithas absorbed heat enough to become useless.

I claiml. A rotary pump comprising a casing having a closed gas-chamberin the interior there-v of and a separate rclosed gas-chamber also formed in the casing and surrounding the interior chamber, a series of plunger-chambers each one of which extends from one of said closed 'gas-chambers to the other, a plunger adapted to reciprocate in each plunger-cham-` ber and having a valve adapted to be opened during the movement of said plunger in one direction but not in the other, a valve controlling the communication of each plungerchamber with one of said gas-chambers, said valve being adapted to be closed when the plunger-valve is open, means for reciprocatother, substantially as described..

2. .The combination with `a casinghavingan interior closed glas-chamber, providedwitlian y inlet forthc gasvtoi'becompressed, of an annular gas-chambenin said casingnsurroundf ing said closedy chamber .and adapted to' vreth'ereof, :a series of' plunger-chambers extending. from .saidannular gas-chamber to2 saidA interior gas-chamber, Ya plunger adapted tol reciprocate in each plunger-chamber; Va shaft extending through the rvinterior gas-chamber;

and having aneccentriem'ounted thereon, a

friction devices or rollersbetweensaidleccentric and-saidV ring, Aa shoeconnected with each retained inan undercut groovewalong the outer periphery of saidiiioat,=fa valve in eachA plunger adapted t'oibeopcn during the movement of said plunger toward said interior gasohamber and to. beclosed during the-move-u I ment of .said plungerin' the; opposite direction, and a .valve .interposed between .each plunger-chamber and theannular -gas-chamber adapted to be opened during the movefmentof the plunger vtoward the sameand.y to

be closed during th'enmovement of the lplunger i in theopposite direction, described.

3. In' a rotary pump,` the combination with chamber firstnamed, all ofthe .plunger-chambers extendingy from. onefgas-chamber to the other and communicating with both, a plunL-v. ger inv each plunger-chamber, land-means fory reciprocating the same, a gas-inlet to 4-one of. said gas-chambersand a gas-outlet -fromthe other, a valve-ink each plungerI adapted to be Aa closed during thelmovement thereof toward thechamber withthe outlet, a valve controlling the communication of each plunger-cham-E ber with the gas-chamber having the outletf, l anda water-jacket. for the plunger-chambers f comprising an annular groove eXtendin galong y each wall of the casing, transverse -.passages-- through the said casing between theplungerchambers to afford communication between said annular-grooves, and a cover4 oriclosuref foreach groove adapted to be secured to the` side of thecasing over the said groove,'sub.- stantially. as and for the purpose describedn a plunger-chamber, an annular valve-seat formed in said bushing, a valve seated thereon, opening. in said bushing above saidv cation with all the plunger-ch ambers through said openings Vin the severalbushings, anfannular channel in1 lthe interior of eachbushing surrounding the-valve,4 a plunger-longitudinally movable in each of lsaid bushings-y K v and .itselflprovided with a valve, vmeans for ceive and-delivergas after the-compression reciprocating said plungers whereby thegas.-

maintain .the bushing in positionfsubstantiallyas described.

- l 5.: In" a rotar um lthelcombination with plunger and having a portion adaptedtoi .be s y p p,

' as-.chamber and anannular closedgas-chamer .surrounding theinternal chamber, of ra-V a cylindricalv shell having an internal closedy ular chamber` tol the 'internal chamber,-a

- to be secured to the outside of the casingat r each opening, to closefthe said openings vand ring; or. .float surrounding said -eccentric-,'..anti-;ll

ushi'ng for eachv bore provided with a shouler, an enlarged mouth for each bore eXtendngV material. supported upon-the said shoulers, a bonnet Aprovidedwith a tongue adaptyd to' engage said` packing material, 'a plu-na casing providedwith a series of radial plunger-chambers, of a .gas-.chamber intlreinterior of said `"casing,- a :second gas-chamber.` formed inthe casing, and surrounding the gas-,

er. longitudinallymovable in andffltting theushing in. each bore,. said plungers being .y dapted -tobe operated` by an eccentric mountd on a shaft extending transverselythrough he said. shell, andV valves to control the pas-- s=described.

stationary cylindrical casing provided with yhatonthe bushing, anannularring of pack-l IOO . age of Vgas through the plunger fromoneof he gas-.chambers tov the other, substantially o.y In a rotary pump, the combination with series of .radial plunger chambers, of a elosedgas-chamber within said casingt and 'f comm unicating with all ofsaidplun ger-,chamers,:anl annular gas-chamber'also formed in' hecasing andsurrounding the gas-chamber rst-named, andA also communicatin'g'with all f said'y plunger-chambers, a plunger in ,eachl f said vplunger-chambers, an eccentric rotatably mountedwithin said' casin'g, a ring sur- Irounding thefsaid eccentric, the periphery of hich rin'gzis'adapted to'coactdirectly'with movement thereof, antifriction devices interposedbetween said eccentric and said ring,

scribed. i

7. In a rotary pump, the combination with the gas-chamber, of gas-compressing devices,

Ithesaid-.plungers to produce a reciprocatory anl actuating -fshaft therefor, a bearing for l said. shaft in one wall of' said chamber -having a countersunk or tapered mouth adapted to coperate with an annular tapered shoul-.f-

der or enlargement on 'the said shaft, a bearing for the said shaft in the opposite wall of said chamber, an oil-chamber inclosing said bearing and itself provided with a packed supplemental bearing for the saidvshaft, the

sectional area of said shaft where it passes through said supplemental bearing being less than the sectional areathereof at the main bearing, whereby a certain area is subjected to unbalanced pressure of gas which may have escaped into the oil-chamber, said pressure tending to move the said shaft longitudinally and bring the annular shoulder thereof into engagement with the annular mouth of the bearing at the opposite end, substantially as and for the purpose described.

8. The combination witha casing having an interior closed gas-chamber, ,of an annular gas-chamber formed in said casing and surrounding the said interior chamber, a series of plunger-chambers extending from one of said gas-chambers to the other, a plunger adapted to reciprocate in each plunger-chamber, a shaft extending through the interior gas-chamber and having an eccentric mounted thereon, a ring or oat surrounding the said eccentric and adapted to coperate with the plungers aforesaid to producev the reciprocatory movement thereof, antifriction devices interposed between said eccentricrand said ring, a valve in each plunger adapted to be open during the movement of said plunger in one direction and to be closed during the movement thereof in the opposite direction, and a valve interposed between each plunger-chamber and one of the said gaschambers adapted to be open during the movement of the plunger toward the saine and to be closed during the movement of the plunger in the opposite direction, substantially as described.

9. In a rotary pump, the combination with a cylindrical shell having a longitudinal opening through the middle, of an annular closed chamber formed in the said shell and surrounding the said opening, a series of plunger-chambers extending from the said opening 'to the said annular chamber, a plunger vineach plunger-chamber, a valve in each ger movesin its operative stroke, ashaft having an eccentric cooperating with said plungers, the said shaft extending through the opening in the shell, bonnets for the ends of the shell having bearings for the shaft, the

said bonnets closing the opening in the shell so that the said opening and bonnets constitute a closed gas-chamber; and gas-passages` communicating respectively with said closed gas-chamber and the annular chamber aforesaid, substantially as described.

10. In a rotary pump, a casing having an interior closed gas-inlet chamber, of a gasoutlet chamber surrounding the said inletchamber and also formed in the casing, a bore or opening extending from the outside of the casing through the gas-outlet chamber to the gas-inlet nchamber, a bushing inserted in said bore, an annular valve-seat in said bushing, an opening in said bushing above said valveseat to aiford communication with the gasoutlet chamber, a valve coperatingwth said seat, a bonnet secured to the outside of the casing to hold the said bushing in place, a spring interposed between said bonnet and said valve, a plunger fitting said bushing, the face ofsaid plunger being adapted to engage and lift the said valve, means for reciprocating said plunger, an opening in said plunger controlled by a valve adapted to be' Witnesses: K H. J. LIvERMoRE, NANCY P. FORD,

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2612837 *May 21, 1946Oct 7, 1952American Eng Co LtdPump
US2693150 *Jun 13, 1950Nov 2, 1954Smith S Jacking Systems LtdPump
US4332532 *Oct 30, 1979Jun 1, 1982Zahnradfabrik Friedrichshafen, AgPiston pump, especially radial piston pump
US4441865 *Dec 4, 1981Apr 10, 1984Wabco Fahrzeugbremsen GmbhFluid pressure pump
US4727794 *Jan 20, 1987Mar 1, 1988Kmicikiewicz Marek ARadial engine
US4907950 *Aug 29, 1988Mar 13, 1990Pierrat Michel AVariable positive fluid displacement system
US5180292 *Aug 28, 1991Jan 19, 1993General Motors CorporationRadial compressor with discharge chamber dams
Cooperative ClassificationF04B1/053