US3050009A

US3050009A - Postitive pressure pump

Info

Publication number: US3050009A
Application number: US65699A
Authority: US
Inventors: Lowry Herman Dale
Original assignee: LOWRY HYDRAULIC CO
Current assignee: LOWRY HYDRAULIC CO
Priority date: 1960-10-28
Filing date: 1960-10-28
Publication date: 1962-08-21
Anticipated expiration: 1979-08-21

Description

Aug. 21, 1962 H. D. LowRY POSITIVE PRESSURE PUMP Filed 001'.. 28, 1960 INVENTOR.

Heey/QN DALE Lon/ey 3,050,009 POSITIVE PRESSURE PUMP Herman Dale Lowry, Los Angeles, Calif., assignor to Lowry Hydraulic Co., Santa Monica, Calif., a corporation of Nevada t Filed Oct. 28, 1960, Ser. No. 65,699 3 Claims. (Cl. 10S-125) The present invention relates generally to uid pumps and more particularly is ldirected to a positive pressure pump having unusually high fluid pumping capacity for its size and weight.

In general the preferred embodiment of the invention hereinafter illustrated and described in detail contemplates the provision of a hollow housing or casing within which are formed a central cavity and a number of `outer cavities arranged in symmetrical rela-tion yabout the central cavity. The cavities are deiined by generally cylindrical walls, and each of the outer cavities overlaps the inner cavity whereby the inner cavity is in fluid communication with each of the youter cavities through openings constituting interruptions in the cylindrical side wal-ls. An impeller member or rotor is rotatably mounted within the central cavity. The rotor proper is of somewhat smaller radius than -the radius of the central cavity and the periphery of the rotor is provided with a number of equally arcuately spaced ribs extending longitudinally of the rotor and projecting outwardly into sliding, virtually Huid-tight contact with the central cavity wall. In each of the outer cavities there is rotatably mounted `an idler wheel having a generally cylindrical outer surface in sliding, virtually uid-tight contact with the cylindrical side wall defining its cavity, the outer surface rof the idler wheel being interrupted by a plurality of equally arcuately spaced longitudinally extending grooves. The spacing of the longitudinal ribs or ridges of the rotor and the grooves of the idler wheels, as well as their respective sizes and shapes, permits the ridges to be received in the grooves during rotation of the rotor, thereby rotatably driving the Wheels. The contact of the ridges with the grooves, supplemented by contact between the peripheries of the rotor and the idler wheels, makes a continuous virtually fluid-tight seal during rotation and the end surfaces of the rotor `and wheels are -similarly in virtually huid-tight contact with the internal Walls of the housing. 'Ihe construction includes passageways or channels whereby to feed incoming fluid to be pumped to corresponding sides of the idler wheels near their juncture with the rotor and similar output passageways or channels are provided on .the opposite sides of the rolling junctures between the rotor and wheels. Rotation of the rotor by an external source of power causes pumping of fluid through the channels just mentioned in somewhat the same way as the operation of a conventional gear pump.

A particular advantage of the present invention is its adaptability for extreme light-weight construction while maintaining Ia volumetric eicieney approaching 0 percent. This is accomplished by the use of interference tts between the various moving parts and between the moving parts and the stationary portions of the housing, the parts in abutting sliding contact being made of a material having some yielding or resilient characteristics such as Teon, nylon or the like. This construction virtually eliminates Huid slippage and cavitation and the pump as a result has unusually advantageous. suction characteristics in use. The ridges carried by the rotor g Patented Aug. 2l, 1952 may be integrally formed with the rotor or, Ias ywill be described hereinafter, may desirably take the form of rollers received in 'grooves formed in the rotor periphery, the'outer ends of the rollers being received in guide channels formed in the housing of the pump. Such construction permits the rollers to distribute ythe wear on their surfaces and yfurthermore yfacilitates easy removal `and replacement of the rollers when desired. Thus, the eiiiciencygof the pump can be maintained at a very high level. The resilient or the yielding characteristics of the several components ofthe pump permit handling of tluid having some solids therein, and the presence of such Small solids does not harm the pump structure. For this reason the pump is particularly well adapted to the pumping of oil and similar fluids where some solid particles may be rentrained in Ithe fluid. The rollers themselves may be hollow or tubular in form in order to additionally permit some yielding when necessary during operation.

Accordingly, it is a principal object of the present invention to provide a novel pump of high etliciency and capacity for its volume and Weight. Additional objects and pur-poses of the invention are to disclose of the 4above characteristics wherein ya central rotor provided with outwardly projecting ridges is elfectively in mesh with a plurality of idler wheels having grooves for receiving the ridges therein, the wheels being in huid-tight contact with the rotor and with the xed portions of the housing of the pump; to disclose such a construction wherein major components are made of a material having -at least slightly yield-ing characteristics in order to permit .a negativ-e or interference lit between the parts; to provide such a pump cap-able of handling small solid particles in the huid pump without substantial harm to the pump itself; and for other objects and purposes as will become clear from a reading of the following description of a preferred embodiment of the invention taken in connection with the accompanying drawing in which:

FIG. 1 is a'side elevational view of a pump embodying the present invention.

FIG. 2 is an end View thereof.

FIG. 3 is a sectional View of the pump taken on line III-Ill of FIG. 4.

FIG. 4 is a sectional View taken on line IV-IV of FIG. 3.

FIG. 5 is a fragmentary view of the central portion of FIG. 4 showing a modied construction of the rollers carried by the rotor.

Referring now in detail to the drawings, a pump embodying the 'present invention is indicated generally at 10 in FIG. 1 and includes a central core section indicated generally at 12 sandwiched between left and right end members indicated generally at 14 and 16, respectively. The parts are held in assembled relation by suitable means such as through bolts 18 and the central core is provided with openings constituting inlet and outlet ports Z0 and 2,2, respectively. As will be seen in FIG. 2, the inlet and outlet ports may be connected to suitable conduits or

pipes

24 and 26, respectively, for connection to uid lines as desired.

Reference to FIGS. 3 and 4 will show the internal construction of the core member 12. A number of cavities are formed within the core including a central cavity indicated general-ly at 30 and a number of outer cavities indicated generally at 32, 34 and 36, the outer cavities being equally spaced arcuately .about the center of the central cavity 3l). Each of the outer cavities is of such a size and so located relative to the central cavity Sil that the central cavity overlaps each of the three outer cavities so that the cavities are in luid communication `with one another through openings constituting interruptions in the cylindrical side walls of the several cavities.

Rotatably mounted within the central cavity an impeller member or rotor indicated generally at 38 land having a generally cylindrical peniphery itl at a substantially smaller radius from the center of the pump than the cylindrical wall 4Z delining the cavity 3S. Means are provided forming in eiect longitudinally extending ribs equally arcuately spaced about the periphery of the rotor 38 and projecting outwardly into sliding contact with'the inner wall 42 of the central cavity. In the present illustrative embodiment of the invention such longitudinal ribs are formed by a number of rollers 44, each roller being received lin a longitudinally extending groove i6 formed in the periphery of the rotor 38 and extending throughout the length of the rotor. Desirably, lthe rollers t 44 extend beyond the ends of the rotor 33, and end portions 48 and Si) of the rollers are received in

annularv grooves

52 and 54, respectively, formed in roller guides S6- and 58. The latter members are seated in suitably formed recesses in the inner surfaces of the end members 14 and 16, respectively. Seal means are desirably provided between the roller gu-ides 56 and 58 and the central core 12 such seals being here indicated at di)y and 62, respectively, and desirably being made of Teilon or a similar smooth-surfaced, preferably somewhat compressible material.

With further reference to FIG. 4, idler wheels indicated generally at 66, 68 and 70 are rotatably received within the

cavities

32, 34 and 36, respectively. The idler wheels have ya generally cylindrical periphery interrupted by a plurality of equally arcuately spaced longitudinally extending grooves 72. These grooves are so shaped as to partially receive rollers d4 during rotation of the rotor 38, as will be understood from a consideration of the dierent positions of the various parts as seen in FIG. 4. Rotor 3S is provided with a central bore 76 and is mounted upon a central shaft indicated generally -at 78 and is keyed thereto at 80. Shaft 78 is carried by bearings S2 mounted Within the end members 14 and 16 and the shaft projects rightwardly as seen in FIG. 3 outwardly of the pump passing through a suitable sealing means 84 to be connected to a suitable source of rotational power for operation of the pump. Under some circumstances, a thrust load may be present and in the present embodiment of the invention such a load may be borne by the thrust bearing 86 mounted in the end member i4 and abutting an enlarged portion 88 of shaft 78. The

idler wheels

66, 68 and 70 may be centrally bored `and Vmounted upon shafts 90, although this is not always necessary since kthe outer cavities within which the idler wheels rotate extend cylindrically well over one-half a circle and therefore the idler wheels can float Within their respective cavities. As will be seen in FIG. 3, support shafts 96,

. i Y ways are formed in the core 12 and lie generally in parallel spaced planes perpendicular to the axis of the shaft 73. Thus, inlet port 2i) is in communication with inlet passageway liiii, while outlet port 22 is in communication with outlet passageway 162. 'Ihe latter Vpassageway is in turn in communication with inwardly directed branch passageways 164, 166 and 108, giving access to the meshing engagement ofthe rotor 38 with idler wheels 32;, 34 and 36, respectively. Similarly, the inlet passageway d is in communication through branch passageways 110, 112 and lll with the opposite sides of the

idler wheels

52, 34 and 36,' respectively. The two arcuate passageways 160 and .1.92 need not extend completely around the pump, although they m-ay he formed in complete annuli if desired. The rollers 44 carried by the rotor 3S may be made of metal or similar material, although by preference they are made of Teilen or equivalent material having some com-pressibility and desirably also self-lubricating qualities. It will be understood thatthe rollers 44 together with the rotor 38 and any of the idler Wheels form a continuous Huid-tight connection during meshing movement of the parts in operation. For some uses it may be desirable to provide greater yielding qualities in the when used, may have their end portions 92- received in bores formed in the end members 14 and 16, respectively, the end portions passing through openings formed in a pair of fixed seals 94 carried by the inner faces of the end members as shown. Seals 94 are desirably made of a material such as Teflon and itis to be particularly noted that seals 94 remain stationary during operation of the pump, while seals and 62.I necessarily rotate about the axis of shaft 78 during operation.

Central coreY 12 is provided with conduit or pass-agev way means for leading fluid to` and away from the mesh- `ing' engagement of the rotor -38v and its rollers-44. with the several idler wheels. In FIG. 4 it is assumed that shaft 78 and therefore rotor 38 are rotating counterclockwisethrough the port 22. A pair of generally arcuate passage-V rollers and for such purpose the construction of FIG. 5 may be used. In accordance with this form of the invention the rollers 144 carried on the rotor 38 are of Teflon or equivalent material and are centrally bored at 146 throughout their length. This permits even greater yielding compressibility by the rollers and accordingly permits thepump to handle lluid containing some solid particles without damage to the pump as the particles pass through.

Modifications and changes from the specilic forms of the invention herein shown as illustrative will occur to those skilled in the art and all such modilcations and changes not departing from the spirit of the invention are intended to be embraced within the scope of the appended claims.

I claimt 1.Y A positive pressure pump comprising:

a housing having formed therein iirst and second partially overlapping cavities having cylindrical side 'walls interrupted toform an opening communicating between the cavities;

a rotor rotatably mounted in the first cavity provided with longitudinal grooves equally spaced about its periphery;

cylindrical rollers partially received in said grooves and in interference lit Contact with the first cavity side wall;

means within the housing for retaining therollers in said grooves during rotation of the rotor;

va Wheel rotatably mounted in the second cavity and having a cylindrical periphery in interference fit con- Ytact withthe second cavity side Wall, said cylindrical Vperiphery being interrupted by a Vseries of equally arcuately spaced longitudinal grooves arranged to successively receive and mesh with the outer portions of said rollers in said opening in fluid-tight contact during rotation of the rotor and wheel, said Wheel periphery and rotor periphery being in interference tit Contact and said wheel and rotor being made of resilient material; V

inlet and outlet conduit means in the housing communicating with opposite sides Yor the meshing contact between the rollers and the Wheel grooves in said opening;

and means for rotating said rotor.

wherein said (References on following page) Referenees Cited in the file of this patent UNITED STATES PATENTS Chapman Mar. 25, 1873 Chapman Mar. 25, 1873 Chapman Mar. 25, 1873 Phinney et a1 Apr. 22, 1879 Thomas Oct. 24, 1950 Devlin Sept. 11, 1951 Maisch Nov. 25, 1952 6 English Nov. 3, 1953 Quintilian Mar. 23, 1954 Quintilian Mar. 23, 1954 Hedman June 22, 1954 Lindquist Dec. 21, 1954 Selden Jan. 1, 1957 Cook et al Jan. 8, 1957 Mori Apr. 30, 1957 Butler Mar. 10, 1959