US3234888A

US3234888A - Rotary pump

Info

Publication number: US3234888A
Application number: US165327A
Authority: US
Inventors: Ralph H Wise; John D Walters
Original assignee: WALTERS
Current assignee: WALTERS
Priority date: 1962-01-10
Filing date: 1962-01-10
Publication date: 1966-02-15
Anticipated expiration: 1983-02-15

Description

Feb. 15, 1966 R. H. WISE ETAL 3,234,888

ROTARY PUMP Filed Jan. 16, 1962 s Sheets-Sheet 1 INVENTORS 4244/ H M55 BY J'ol/N 0 M4755 Feb. 15, 1966 R. H. WISE ETAL 3,234,888

ROTARY PUMP Filed Jan. 10, 1962 5 Sheets-Sheet 2 FaZ We. INVENTQRS FALPH H M55 BY JOHN A/fll-TEE S 450M, 557725 a: Gen/a ,47'7'0eA/E/5 Feb. 15, 1966 R. H. WISE ETAL 8 ROTARY PUMP Filed Jan. 10, 1962 5 Sheets-Sheet 5 .5 4 2'6 .3 F i 7 i r r INVENTORS @ALPH H. M55 BY JOHN 0. hmqsg MLjON, SETTLE & Gen/6 flrrogA/El j Feb. 15, 1966 R. H. WISE ETAL RIOTARY PUMP 5 Sheets-Sheet 4 Filed Jan. 10, 1962 INVENTORS 1611.2 1 H. M55 BY JOHN LIA/517555 M5 Feb. 15, 1966 R. HrwlsE ETAL 3,234,388

ROTARY PUMP Filed Jan. 10, 1962 5 Sheets-Sheet 5 INVENTORS YPKILPH ,4. M55 BY JoH/v a A/nzree United States Patent Ofiice 3334,88 Patented Feb. 15, 1&66

3,234,888 ROTARY PUMP Ralph H. Wise, Dyersburg, and John D. Walters, R0. ;)Kfi595, Dyershurg, Tenn.; said Wise assignor to said a ers Filed Jan. 10, E62, Ser. No. 165,327 1 Claim. (Cl. 103-126) This invention relates to fluid pumps, and more particularly to a rotary fiuid pump wherein a plurality of cooperating impellers define a pulsating cavity or pump chamber, providing a positive displacement type of pumpmg action, but characterized by a substantial absence of wear of moving parts.

In the prior art, a great effort has been made toward the pumping of fluids, such as gases and liquids, and centrifugal as well as positive displacement pumps have been provided. However, the inefiiciencies inherent in centrifugal pumps are well known. Slippages are inherent in such systems, and relatively high power requirements and rotational speeds are required for reasonable efficiencies.

On the other hand positive displacement pumps are characterized by less slippages, but are comprised of many moving parts, all running in frictional engagement with one another, thus contributing to high wear and relatively short life. Characteristic of positive displacement pumps is the piston pump and it is well known that the inertia forces involved in these units at high speeds are substantial, reversing of the weights of the pistons robbing the units of large amounts of power, as when used in refrigeration compressors, air compressors and the like. Also, the positive displacement pumps have been characterized by relatively complicated valving arrangements that are subject to wear and require maintenance.

Accordingly, it would provide a substantial advance in the art if a pump combining the best characteristics of the positive displacement and the centrifugal pump type could be rolled into one, thus providing a pump where there is no actual wearing contact between the working parts, wherein the parts were few in number and simple to manufacture, thus contributing to long life, low initial cost, and low maintenance, and yet wherein positive displacement and high volumetric efiiciencies are maintained.

Accordingly, it is an important object of the present invention to provide a novel pump of the rotary type.

It is a further object of the invention to provide a novel pump of the rotary type wherein a plurality of symmetrical impellers are co-rotated in synchronized relation between a pair of plates to define one or more pumping cavities, and providing extremely high elficiency and positive displacement in a minimum amount of volumetric displacement.

A further object is to provide a pump that is adapted to the propulsion of all types of fluids, including gases and liquids, both corrosive and non-corrosive and either singly or simultaneously, without admixture.

A further object is to provide a novel pump of the co-rotatable cooperating impeller type including a novel valve plate arrangement to alternately fill and discharge internal and external pump cavities with a minimum number of moving parts and with a substantial absence of frictional wear.

Another object is to provide an impeller pump wherein the impellers are ported, thus completely dispensing with wearable valves of the poppet type.

A furtherobject is to provide a novel pulsating cavity pump utilizing a plurality of at least three cooperating impellers, where the peripheries of the impellers run closely adjacent one another to provide internal and external cavities, utilizing a molecular friction seal, void of frictionally contacting parts.

Other objects of this invention will appear in the following description and appended claim, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

In the drawings:

FIGURE 1 is an elevational view of one embodiment of the pump of the present invention;

FIGURE 2 is a plan view of FIGURE 1 with hidden parts in dotted outline;

FIGURE 3 is a vertical section view taken along the line 3-3 of FIGURE 2;

FIGURE 4 is a transverse section view taken along the line 4-4 of FIGURES 1 and 3, showing the impeller arrangement and layout;

FIGURE 5 is a fragmentary section view taken along the line 55 of FIGURES 1 and 3 with hidden parts in dotted outline;

FIGURES 6-8 are schematic views illustrating operation of the first embodiment of the pump of the present invention; and

FIGURES 9-.-1l are schematic views illustrating porting configuration and operation of an internally ported pump embodiment of the invention.

Before explaining the present invention in detail it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Perspective view Briefly, the present invention relates to a novel rotary pump of positive displacement characteristics wherein two opposed spaced, generally parallel plates provide a housing or chamber within which a plurality of at least three flattened, symmetrical impellers are positioned for synchronized co-rotation on their geometric centers or axes. By the present invention, the centers of the impellers are so spaced that upon rotation in a common direction, portions of the peripheries of the impellers run in closely adjacent, but non-contacting relationship so that at operational speeds, a fluid friction seal is provided between the peripheries to define a pulsating cavity within the rotational centers of the impellers, that is of changeable volume and thereby adapt to draw in and expel fluid and thus provide a positive displacement pumping force.

Within the extended scope of invention, a wall can be placed in surrounding relationship to the impellers to define one or more pulsating cavities exteriorly of the peripheries of the impellers; thus, pumping is produced on both sides of the impellers to provide greatly increased capacity by the same volumetric displacement of the impellers themselves.

It is an extremely important aspect of the invention that the peripheries of the symmetrical impeller units are not in actual contact frictional engagement with one another; thus, long life is assured by the absence of parts frictional engagement and wear between these parts.

According to the invention, one form of valving arrangement utilizes a rotatable valve plate, cooperating with appropriately oriented fixed ports to alternately fill and dump the pump cavities, using minimum parts and characterized by substantial absence of wear. Further, a novel porting arrangement can be utilized in one or more of the impellers themselves, still further reducing aaseese production costs of the present pump yet retaining the same high efficiencies.

It is a further important aspect of the present invention that only about ten basic parts are used for manufacture with only about 25% of the overall volume of a conventional piston pump of equivalent capacity; and that the working parts such as impellers and impeller chamber can be made with only moderate accuracy, thus contributing to lowest cost per uriit output, with simplicity of part shape such as plate and circle and adaptation to a broad range of fabrication materials.

These important features and others along with exact details of description of the invention will be brought out in the following description, using the present brief resume as a background outline for extended development;

The invention As shown in FIGURE 1, apump 1t) embodying the rotatable impeller concept of the present invention is illustrated, as for example as applicable to the pumping or propulsion of fluids such as gases or liquids as in household refrigerators, home water systems and chemical plants. Thus, the pump includes an impeller casing 12of generally square outer configuration, as seen from the top plan view of FIGURE 2, on top of which there is mounted a top plate 14, containing appropriate porting and valve arrangement for the intake and exhaust of fluids, as will be hereinafter described. However, at this point it should be noted that the top plate 14 includes an upwardly extending port and valve plate chamber 16, having an conduit-connection cap 18 secured thereto as by two opposed bolts 20 and a third bolt 22 of longer configuration adapted to extend the entire length of the unit.

At the bottom of the impeller casing 12, a seal-carrying plate 24 is provided, carrying suitable seals which retain the pumped fluid within the impeller casing 12, thus preventing leakage to other parts of the mechanism. Beneath the seal carrying plate 24, there is positioned a bearing carrier bottom plate 26, beneath which is positioned an inverted dome-like gear casing 28.

The impeller casing 12, top plate 14, bottom sealcarrying plate 24, bearing carrier bottom plate 26, and gear casing 28 are secured in assembled relationship by the longer bolt 22 with nut 3t) and lock washer 32; and by shorter bolts 34, which also use the same size nut and lock washer 3t and 32. From the plan view of FIGURE 2, it will be noted that the one longer bolt 22 and three shorter bolts 34 are utilized for the overall assembly.

It will be noted that the gear casing 28 has an annular flange 35 at its top end, of a peripheral dimension equivalent to the peripheral dimension of the bearing-carrier bottom plate 26; this flange, like the other units previously named with which it is stacked, is provided with appropriately aligned apertures to receive the bodies of the

bolts

22 and 34; thereby all parts can be assembled and locked in coaxial alignment.

As shown in FIGURES 1 and 3, an oil fill plug 36 is provided in the upper portion of the gear casing 28 and a drain plug 38 is positioned adjacent the bottom wall 40, to provide lubricant.

The remainder of the unit, as shown in FIGURE 1, includes a bearing retaining annulus 42, positioned coaxially of the bottom 40 of the gear case 28, extending downwardly therefrom to avoid bearing crowding, as shown in FIGURE 3. A power input shaft 44 is extended through a bearing carried within the retainer annulus 42 and the shaft is used to drive a planetary gear set positioned within the case 23 for co-rotation of the impellers in synchronized relation to provide pumping in accordance with the pulsating cavity concept of the present invention. At this point it may be noted that the terminal end of the power input shaft 44 is suitably provided with a keyway 46 for connection of a suitable drive pulley or gear, whereby the unit it) can be drivi'ngly related as by belt, chain, gear, sleeve shaft coupler or the like, to a prime mover, such as an electric motor, gasoline engine of the like.

In view of the foregoing brief introductory description and orientation view, the various components contained within the pump 10 and their operable interrelationship will now be described in full detail.

The impeller housing and typical impeller layout As best shown in FIGURES 3 and 4, impeller casing 12 includes an endless, axially extending wall 48 that defines four, part circular chambers 50, within which impellers 52 are respectively positioned for synchronized co-rotation at their geometric centers 54. As best shown in FIGURE 4, the impellers 52 are of ellipsoidal configuration in plan view and their centers 54 are spaced on the corners of a square whereby portions of the perimeters of the impellers are in substantially contacting, but very slightly spaced relationship with one another, thereby avoiding sliding friction. By reference to FIGURE 4 and FIGURES 6-8, it will be noted that the peripheries of adjacent impellers are always close to one another at some point during rotation to provide an enclosed cavity within the centers of the impellers or at the center of the mentioned square, as well as an exterior cavity or cavities exteriorly of the impellers. Also it should be noted that the longitudinal sectional axes of adjacent impellers are oriented to one another.

Although a very slight gap can exist between the peripheries, with no frictional contact engagement and consequently no wear, yet as previously mentioned, at operating rotational velocities, a molecular friction seal is established between the closely spaced peripheries, equaling in effect the efficiency of a sliding seal. Thus, actual contact as by a physical friction seal is not necessary to the operation of the present pump. However, it is to be considered an optional embodiment of the invention, if desired, to provide sliding or floating seals as where specialized application may warrant the extra cost, wear and maintenance, for pumping fluids of peculiar nature.

It is to be understood that the clearance between the peripheries of the impellers and the intern-a1 walls of the part circle chambers 50 can vary substantially within the broad scope of invention; thus, there is no wear between either the peripheries of the impellers themselves or between the peripheries of the impellers and the walls of the chambers in which they rotate. When the clearance is increased to permit breathing between the outer cham bers, the outer chambers in eflect blend into one larger chamber which also pulsates in the manner of the inner; chamber, but 90 out of phase.

As shown in FIGURE 3 the impellers are of a thickness calculated to give a desired volumetric displacement; for given size pumps and/or available power, to operate. However, as will be understood, this is subject to variation and can be changed for producing pump-s of differ-- ent capacity.

By reference to FIGURE 3, it will be noted that a; fairly close fit is provided between the upper and lower surfaces of the impellers and the upper end lower plates 14 and 24. This substantially eliminates blow-by from the internal chamber to the exterior chamber and provides high pumping efficiency; however, slight clearance is preferred so that again there is no frictional engagement the parts to restrict free rotation of the impellers and thus lubrication is not needed. Any blow-by between the inner chamber and the outer chamber or vice versa over upper and lower surfaces of the impelles or between the peripheries of the impellers for that matter, will be pumped by that chamber into which it is exhausted; however, when it is noted that a high pulsation can take place in the present pump, any blow-by will tend to stagnate on the top of the impeller and thus form a stationary seal. However, where it is desired, it will be understood that a seal, such as a carbon seal, can be provided between the upper and lower surfaces of the impellers and the bottom and top surfaces respectively of the top plate 14 and the bottom plate 24.

It will be briefly pointed out at this time that a valve system is provided in the port chamber 16, being formed integrally on top of top plate I l for the alternate inlet and exhaust of fluids by each of the inner and outer chambers defined by the impellers for pumping purposes. Thus, as will be more fully hereinafter described, fluid is drawn from an intake line connected to the conduit connection cap 18 first into the inner chamber and then into the outer chamber and is alternately exhausted from these chambers in a repeating cycle.

The impeller mounting and gearing assembly By reference to FIGURE 3, the typical manner in which the impellers 52 are mounted for rotation is illustrated.

T-hus, three of the impellers 52 are mounted on shorter shafts 56 and one of the impellers is mounted on a longer shaft 58 that extends up into the port chamber 16 for rotating a valve plate. It will be noted that each of the shafts is supported medially within a bearing 69 provided in appropriate recesses s2 in the bearing carrier bottom plate 26. The bottom ends of all of the shafts 5i: and 58 are carried in similar bearings 64- provided in recesses 66 in the bottom wall 40 of the gear case 28.

Above the bearings 60 and around each of the shafts 56 and 58 there is provided a short spacer sleeve 68 that extends partially through the bearing carrier bottom plate 26, above the bearing, and all the way through the sealcarrying plate 24, upwardly to contact the bottom of each of the impellers 52 to provide proper spacing alignment for these units. The impellers are locked in place on their shafts by keys 7t Annular seals '72 are carried by the seal-carrying plate 24 within apertures '74 provided therein to prevent fluids in the impeller chamber 48 from leaking to other parts of the mechanism. Also, as shown in FIGURE 3, an aperture '76is provided inthe top plate 14 that also contains an annular seal 72 through which the extended portion 59 of shaft 58 is inserted, to similarly prevent leakage at that point.

Thus, all shafts 56 and 58 are journaled for rotation with impellers 52 locked on the upper ends thereof within the impeller casing 12, one of the shafts extending upwardly through the impeller casing for the operation of a valve plate to be subsequently described.

Beneath each of the bearings 60 carried by the bearing carrier bottom plate 25 on each of the impeller shafts 56 and 58 there is provided a planetary gear as, all four being operably aligned and fastened to the impeller shaft as by means of keys (not shown).

Coaxially of the pump, there is provided the power input shaft 44 journaled at its top end in a bearing 60, also carried in a bore 62 formed in the lower side of the bearing carrier bottom plate as. The bottom end of the power input shaft 44 is reduced in diameter for insertion through a bearing 64 carried in a recess 65, formed in the bearing retainer annulus 42; the bottom end of the upper, larger portion of the power input shaft provides a shoulder 80 for axial positioning of the input shaft.

Carried by the input shaft 44 in alignment with the planetary. gears 78, is a sun gear 82 having teeth adapted to mesh with the teeth of the planetary gears 78. Thus, the power input shaft 44 is supported for rotation in synchroni-srn wtih the planet gears 78 and adapted to drive the same and thereby rotate the impellers in synchronized co-rotation in the same direction.

By reference to FIGURE 4, it will be noted that the longitudinal section axes of adjacent impellers are oriented 90 with respect to one another, thus assuring that on co-rotation in the same direction, at least a portion of the periphery of each adjacent impeller always runs in closely adjacent spaced relationship to a portion of the periphery of the next adjacent impellers to provide the molecular friction seal heretofore mentioned.

The pulsation Having thus described the mechanism for rotating the impellers and their orientation with respect to one another, by reference to FIGURES 6, 7 and 8, it will be noted that during rotation of the impellers in the arrow 84 direction, when the small ends of the impellers are all directed to the center, the inner cavity 86 is of minimum volume and as shown in FIGURE 7, when the impellers are rotated from their FIGURE 6 position, the inner chamber is at maximum. From the foregoing, it will be understood that upon rotation of the impellers, this pulsation is repeated two times per revolution. Also, it will be noted that while the inner chamber 86 is contracting or expanding in size, the outer part circle chambers 56, either individually, or collectively as a large common chamber 88 also contract and expand. Thus, as shown in FIGURE 6, when the inner chamber is at minimum volume, the outer chamber is at maximum volume; also, as shown in FIGURE 7, when the inner chamber 86 is at maximum volume, the outer chambers 5-1) or 88 are at minimum volume. Thus, pulsating cavities are formed both interiorly and exteriorly of the impellers.

As these cavities alternately contract and expand, fluid is alternately drawn into and expelled from each cavity, using a suitable valving arrangement, to proivde a highly efficient pumping action.

An external valve system A typical so-called external valving arrangement will now be described.

By reference to FIGURES 2 and 3 it will be noted that an intake conduit connection 90 is provided on one side of the conduit connecting cap 18 and an exhaust conduit connection 92 is provided on the other side of the conduit connecting cap. As shown in dotted outline in FIGUREZ, a kidney-shaped passageway or port is provided in the conduit connection cap 18 beneath each of the intake and

exhaust conduit connections

90 and 92. Thus, the intake conduit connection 90 leads into a kidneyshaped or semi-annular intake port 94 and the exhaust conduit connection 92 is open to a kidney-shaped exhaust port 96.

As best shown in FIGURE 3, a rotatable valve plate 9%; of circular configuration and having a coaxially extending sleeve portion 1th) is bored coaxially to fit upon the upper end 59 of impeller shaft 58. The shape of the valve plate 98 is best shown in FIGURES 6, 7 and 8, it being noted that it is a true circle with opposed apertures 102, alignable with the kidney-shaped intake and

exhaust ports

94 and 96, previously described. Beneath the valve plate in the port chamber 16, are also provided kidney-shaped ports similar to the

ports

94 and 96 previously described. However, as shown in FIG- URES 5-8, these are oriented 90 from the intake port 94 and exhaust port 96 previously described. Thus a kidney-shaped port 164, for the inner impeller cavity 86 andan opposed kidney-shaped pol-r106 for the outer impeller cavity 88 are provided. The inner cavity port .1434, as best shown in FIGURE 3, is connected by a short passage 168 to the center of the inner cavity 86 defined by the impellers 52. Also, the outer kidneyshaped port 106 is connected by a passage 110 to the outer chamber 88 defined between the impellers and the wall 48 of the impeller casing 12.

Having described one suitable valving system to provide the completed unit, the manner in which the valves and the impellers, forming pulsating cavities, cooperate to provide a highly effective and positive displacement pumping action will now be set forth.

ifull exhaust, and again to full intake. bottom of FIGURE 8, the lower aperture 102 of the valve plate 98 is switching the inside chamber from ex- At the same time the upper aperture Operation Operation of the pump of the present invention is best understood by reference to FIGURES 68. At the position of the impellers 52, as shown in FIGURE 6, the inside chamber 86 is reduced to smallest volume and the external chamber 88 is at largest volume. This can be called the position. Also, as shown in FIGURE 6,

the valve plate 98 is just moving the ports 102 from exhaust of the inlet chamber to intake of the inlet chamber and is reversing the outside chamber from the opposite condition, i.e., from intake to exhaust. Thus, the upper port 102 of plate 98 is switching from inlet to exhaust and the lower port is doing the opposite. Thus, as shown in FIGURE 6, the inside chamber is at full exhaust just ready to start intake and the outside chamber is at greatest volume or full intake, being filled with fluid and completing its inlet cycle just before starting to exhaust.

As shown in FIGURE 7, the impellers and the valve plate 98 are rotated 90 from their position in FIGURE '6. This means that the inside chamber is now at full intake volume and the outside chamber is at minimum volume or full exhaust. Thus, the inside chamber 86 is full of inlet fluid and is about to start exhaust; the outside chamber is completing its exhaust stroke and is about to start to intake. By reference to the valve plate and port set-up at the bottom of FIGURE 7, it will be noted that the right aperture 102 is switching the kidneyshaped inlet port 94 from the inside chamber to the outside chamber; this means that the outside chamber having completed its exhaust, will now begin to intake. The

left port 102 of the valve plate 98 is now switching the outside chamber from exhaust over to the inside chamber so that it can exhaust. Thus, in summary the inside chamber 86 being full of fluid, is switching from intake to exhaust and the outside chamber having finished its exhaust stroke is switching from exhaust to intake.

In FIGURE 8, which is a 180 rotation from FIGURE 6 and a 90 rotation from FIGURE 7, the valve plate 98 has turned 90 along with the impellers 52 and the inside chamber is now at minimum volume and the outside chamber at maximum volume. Thus the inside chamber 86 is completing its exhaust stroke having cycled completely through intake and exhaust from. FIGURE 6, and the outside chamber 88 is completing its intake stroke, :also having completed its cycle from full intake through As noted at the haust to intake. 162 of valve plate 98 is switching the outside chamber from intake to exhaust. Thus, the inside chamber has substantially completed its exhaust stroke and is again switching from exhaust to intake; simultaneously the outside chamber 88 has completed its intake stroke and is switching from intake to exhaust. Thus a full cycle of both chambers has been completed on 180 of rotation thus providing two pulses per revolution.

Repetition of this cycle in a rapid manner provides a very positive displacement pumping action.

During the rotation of the impellers, lubricating oil in the gear casing 28 coats the bearing 64 and is splashed by the planet gears 78 and the sun gears 72 on upper bearings 60 to provide positive lubrication of all frictionally engaged parts of the pump, thus contributing to long life. The valve plate receives lubrication from the fluid being pumped or sealed bearings can be provided above the upper cavity 76 of seal '72 and clearance provided for pumping gases of non-lubricating character.

When it is understood that the foregoing sequence of events, that is the contraction and enlargement of the inner and outer chambers defined by the impellers, takes place at an appropriate rate of speed, it will be understood that the peripheries of the impellers pass each other at a rapid rate, providing a molecular friction seal,

even though they are not in actual contacting relationship. It will also be understood that the rapid pulsation of the inner and

outer cavities

86 and 88 practically stabilizes any blow-by between these chambers across the top and bottom surfaces of the impellers to provide an effective seal, substantially preventing leakage between these cavities. Also, the annular seal 74 prevents the fluids being pumped by the impellers 52 from leaking to other parts of the mechanism.

An internally ported modification From the foregoing description, it will be noted that one suitable external valving arrangement can be utilized to provide a pump utilizing the pulsating cavity concept of the present invention. However, other valving 'arrangements can be provided and the broad scope of the invention is not to be limited to any particular valving set up, although the unit shown is an extremely effective arrangement with a minimum of moving parts. Thus ports can be used as follows.

To illustrate schematically one manner in which intake and exhaust ports can be provided in each of the impellers, reference is made to FIGURES 9-11 which provide a schematic illustration of the operation of the pump of invention when each of the impellers is both internally and externally ported to an appropriate intake manifold and an appropriate exhaust manifold provided on top of the unit. Thus, as shown in FIGURES-941 each of the impellers 52 is provided with two intake port systems 112, each comprising a vertical passage 11 i and one or more horizontal passages 116, connected to the vertical passage and extending to the periphery of the impeller. In alignment above the circle of rotation of the vertical passages I14, there is provided a semi-annular groove H8 in the top plate 14 of the pump; thus, a vertical passage ill icomes into alignment with the top plate groove I18, fluid can ilow into the inner chamber 36 or into the outer chamber 88 from the top plate grooves 113, vertical passages I14, and the horizontal passages 116, from a suitable intake manifold arm. A suitable vertical aperture is provided in the top plate 14 above each of the half circle grooves 118, to connect to the intake arm, which is in turn connected to an intake header. The configuration of only one impeller is described because all are alike as regards the intake system.

Similarly an exhaust port system is provided for each of the impellers 52 for exhausting fluid both from the inner cavity 86 and from the outer cavity 83. Thus, each impeller 52 is provided with two exhaust port systems 120, each comprising a vertical passage 122 and one or more horizontal passages 124, connected to the vertical passages and extending to the periphery of the impeller. 1n aligned relation above the circle of rotation of the vertical passages 122 there is provided a generally half circle groove 126 in top plate 14. Thus, when the vertical passages 122 come into alignment with the top plate groove 126 fluid can be exhausted from the inner chamber 86 or from the outer chamber 88. Thus, by means of an exhaust manifold arm connected by a suitable aperture in top plate 14 into each of the half circle outlet grooves 126, the grooves 126 carry exhausting fluid when the vertical passages 122 come into alignment, the fluid passing horizontally through passages 124 and then through the vertical passages 122 from either the inner chamber 86 or the outer chamber 83. The configuration of only one impeller is described because all are alike.

Operation Operation of the internally ported impeller embodiment of the present invention is best described by reference to FIGURES 9, l0 and 11. FIGURE 9 is at 0 representation wherein the inside chamber 86 is at full exhaust and the outside chamber 88 is at full expansion or full intake. Thus, the exhaust ports 124 have c0mpleted the exhaust of the inner chamber 88 and as the impellers rotate in the arrow 84 direction, the exhaust ports are changing to open to the outside chamber and are thus closing to the inside chamber. Also, it will be noted that the inner intake ports 114 are just coming into alignment with the groove 118 and are opening into the inside chamber so that the intake stroke on the inside chamber can take place. Briefly then, the inside chamber is at full exhaust and the exhaust ports are closing and the intakes are opening. The outside chamber is at full intake; thus, the intakes are closing and the exhaust ports are opening.

By reference to FIGURE 10, which is a 90 rotation of the impellers from the FIGURE 9 showing, it will be noted that the inside chamber is now at full intake and the outside chamber is at full exhaust. Thus, the inside chamber is at full intake and the intake ports are just closing by passing to the outside chamber; also, the exhaust openings are just coming into alignment with the half circle grooves 126 to open to the interior chamber. The outside chamber is at full exhaust; the exhaust ports are closing and the intake ports are opening.

By reference to FIGURE 11 which is a 180 rotation from FIGURE 9, it will be noted that a full cycle has been completed. Thus, the inside chamber is again at full exhaust; the exhaust ports are closing and the intake valves are just opening. The outside chamber is at full intake; the intake ports are just closing and the exhaust ports are just opening.

When the foregoing description is read with an understanding that the impellers are rotated rapidly so that pressure and vacuum conditions are alternately produced Extended scope of invention While the foregoing description has related to one rotary valve arrangement, it will be understood that other types of valving can be used, although the rotary unit shown is highly advantageous from the point of view of few moving parts and long life and freedom from maintenance and forms a preferred embodiment of the present inven tion as compared to more complex poppet valves.

Also, the foregoing description has related to a porting arrangement wherein each of the impellers is internally and externally ported to provide maximum breathing for the internal and external chambers. However, the broad scope of invention would include internal and external porting on one or more of the impellers where lesser flow rates are contemplated and slower rotation is provided and where the impellers are spaced from the outer wall of the impeller chamber to provide in effect one large outer chamber, which could be provided with inlet andexhaust from one or more of the impellers. Also, the broad scope of invention would include an intake port system on part of the impellers and an exhaust port system on others of the impellers or a combination thereof. The important thing is that fluid such as liquids or gases be introduced to the inner chamber on its intake cycle and simultaneously exhausted from the outer cham her on its compression cycle and reversed when the inner chamber starts to compress and the outer chamber starts to expand.

Thus, in view of the fact that a number of dilferent valving arrangements can be provided, the foregoing description provides an explanation of typical arrangements that can be used. Thus, the broad scope of invention encompasses the concept of a plurality of symmetrical impellers co-rotatable in synchronized relation between spaced plates to define a first internal chamber therebetween and optionally a plurality of chambers, or a plurality of chambers working as single chamber exteriorly thereof, wherein both chambers are of a pulsating character, alternately expanding and contracting in volume in the manner of a piston moving up and down in a cylinder in a piston type pump.

As regards this aspect of the invention, it will be noted that either of the internal and

external cavities

86 and 88 works independently of the other and thus the volume of the pump can be reduced by using either of the cavities alone rather than using both cavities as has been previously described, although the foregoing description is preferred for utmost efiiciency within a given volume.

In the broad aspect of the invention the wall 48 of the impeller chamber could be spaced a substantial distance away from the peripheries of the impellers and still provide operability because the impellers would force a change in volume in the outer chamber. Thus, the pump of the present invention could actually be placed in a closed barrel provided with suitable intake and exhaust ports and check valves and provide operability through the pulsating nature imparted to the volume of the barrel by rotation of the impellers. From this, it is: to be understood that a number of very practical and broad range aspects can be attached to the present invention.

In accordance with the invention, it is geometrically practical to design three cooperating impellers. Thus, according to the broad inventive concept, the impellers can be placed with their centers at the corners of either a triangle or square and be so designed and shaped that a constant slight clearance is maintained between portions of the peripheries of adjacent impellers when they are moved in the same rotational direction, causing the peripheral surfaces of adjacent impellers to move in direction opposite one another and form a molecular friction seal.

Also, within the broad scope of invention, the gearing arrangement can be modified for reductions or increases in speed of the impellers as related to the input shaft rotational speed, Thus, the four planet gears shown can be operated within a larger ring gear spidered to the input shaft to provide an increase in speed of the impellers in relation to the speed of the input shaft; this is contrasted to the approximate equivalent speed between the rotation of the input shaft and the impellers as shown in the typical gearing arrangement of the drawings where in the size of the sun and planet gears are approximately the same.

While a single stage pump of given thickness impellers has been shown in the present specification, it is to be considered within the broad scope of invention that the volume of the impeller chamber can be increased by increasing the thickness of the impellers and also multiple staging can be utilized by lengthening the impeller shafts to extend through a plurality of impeller chambers for mounting additional sets of impellers for additional output, or provide staging of increased compression. When so operating, various arrangements can be used as where all of the internal cavities are connected in common by axially aligned apertures through the separator plates; however, the exterior chambers could be connected in commen or separately for moving different fluids. By conduits in the separator plates to the center cavity, a stacked array would also provide for handling different fluids in a common unit.

By providing an appropriate seal at the tops and bottoms of the impellers, it may be possible in some instances to pump one liquid or gas by one of the

chambers

36 and 88 and a different liquid or gas by the other of the chambers, Where inter-mixing between the two chambers is positively prevented as by high precision machining techniques and positive seals, such perhaps as O-rings. Further ramifications of the invention along this line are believed to be obvious and the tremendous applicability of the pumping concept of the invention is to be considered within the scope of the appended claim and therefore further elaboration of further ramifications will not be made to unduly burden the length of the specification.

Materials of construction of the impellers and the impeller chamber may vary, depending upon the nature of the fluid being pumped. Where corrosive materials are being pumped, stainless steel, glass, porcelain, refractories and similar materials will be employed. In this respect, glass and porcelain can be used because of the absence of positive contact between the parts and lack of frictional wear, abrasion and engagement therebetwecn. Other metals and synthetic resins can also be used in appropriate applications and with proper engineering. Thus, Within the broad concept of the invention, a tremendous range of materials can be used for effectively handling many different types of fluids, both corrosive and noncorrosive, including gases and liquids. Where abrasive fluids are being moved, as sand-water slurries and the like, the impellers can be made of various grades of rubber or similar materials or elastorneters which are abrasion resistant for long durability.

Advantages '01 the invention In view of the foregoing description, it will be understood that a novel approach to the production of positive displacement pumps has been provided in accordance with the present invention, a positive mechanical clearance being preferred between moving parts for absence of wear and maximum tolerances of machining for most economical production. Thus, it has been discovered that a very effective positive displacement pump can be provided without the use of frictionally engageable mechanical seals, utilizing instead a molecular friction seal discovery.

By the use of the ellipsoid shape of the impellers, as shown in the drawings and as described in the foregoing specification, the internal chamber is reduced in volume by a factor of about 16 to 1 in a 90 turn of the impellers. By altering the shapes of the impellers, lesser changes in the volume of the cavities can be provided, thus making it possible to use larger or small pressure fluctuations, as desired. This may, but need not necessarily involve modification to the interior surfaces of the vertical wall same or different pumping capacity as the inner chamber.

It will be noted that the number of parts of the pump of the present invention and its volumetric size are sub- 1 stantially decreased from corresponding elements of conventional positive displacement piston pumps. Thus, some 5 to basic par-ts are utilized in a typical prototype pump of the invention, which occupy about of the overall volume of an equivalent capacity reciprocating piston pump. Also, one simple valving system is provided as contrasted to valves for each of the cylinders of 12 a piston pump. Also, by takingadvantage of the pumping capacity of the outside chambers, the tremendous efiiciency from a given volume of the pump of the present invention is illustrated.

5 A further advantage of the invention is that the perimeters of the impellers do not demand extreme accuracy in machining, taking advantage of the molecular friction seal concept. Thus, using a greatly reduced number of parts of lesser machining accuracy, production costs will 10 run approximately of the cost of an equivalent capacity reciprocating piston pump; a conservatlve reduction of of manufacturing costs.

Having thus described our invention, we claim:

In a rotary pump, a pair of opposed spaced plates, an endless wall extending between said plates and defining a chamber, a plurality of at least three impellers of flattened generally ellipsoid configuration in section mounted for rotation on their geometric centers within said chamber, means for co-rotating said impellers in synchronized relation, the centers of said impellers being spaced so that upon said synchronized co-rotation, portions of the pe ripheries of adjacent ones of said impellers are in closely adjacent spaced relation with one another to define a first pulsating cavity interiorly of the centers of said impellers and a second pulsating cavity exteriorly of the centers of said impellers, a fiuid conduit connected to each of said cavities, said fluid conduit terminating in first and second generally semi-circular opposed ports formed in a common circle in a first plate, generally semi-circular inlet 30 and outlet ports formed in a second plate positioned in opposed spaced relation to said first plate and formed in a common circle, said inlet and outlet ports being oriented with respect to said first and second generally semi-circular ports, said ports being positioned in 35 superimposed relation, a circular valve plate positioned between said opposed plates and concentric to said ports and containing spaced apertures aligned with said ports, and means for rotating said valve plate in synchronism with rotation of said impellers.

40 References Cited by the Examiner UNITED STATES PATENTS 2,097,881 11/1937 Hopkins 103- 126 40 2,457,314 12/1948 Lysholm 230-143 FOREIGN PATENTS 91,840 3/1923 Austria. 657,191 1/1929 France. 9,431 6/1916 Great Britain. 00 145,501 1/1921 Great Britain. 483,929 4/ 1938 Great Britain. 484,829 5/1938 Great Britain.

93,979 12/1938 Sweden.

DONLEY J. STOCKING, Primary Examiner.

JOSEPH H. BRANSON, 112., Examiner.