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Publication numberUS2882828 A
Publication typeGrant
Publication dateApr 21, 1959
Filing dateSep 21, 1956
Priority dateSep 21, 1956
Publication numberUS 2882828 A, US 2882828A, US-A-2882828, US2882828 A, US2882828A
InventorsHinckley John N
Original AssigneeHinckley John N
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Pumps having rotors and swinging arms
US 2882828 A
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Description  (OCR text may contain errors)

April 21, 1959 J. N. HlNcKLEY 2,882,828

PUMPS HAVING ROTORS A\ND SWINGING ARMS Filed sept. 21. 1956 2 Sheets-Sheet 1 y m E MH wm l/ N. 0f Mw Sb.,

April 2l, 1959 PUMRS HAVING ROTORS AND SWINGINC ARMS Filed Sept. 21, 1956 2 Sheets-Sheet 2 W4' 535227- 1 @s3 20 I 5 .1'. N. HlNcKLl-:Y 2,882,828

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2s 73- /9 63 L. 64 57* :T/l f/Z ,1A 5%@ United States Patent O 2,882,828 PUMPS HAVING RoroRs AND swlNGING ARMs John N. Hinckley, Belmont, Mass.

Application September 21, 1956, Serial No. 611,143

7 Claims. (Cl. 103-42) This invention relates to pumps having rotors and swinging arms. j

Among the objects of theinvention is to provide a rotary pump suitable for pumping fluids varying widely in viscosity. The structural characteristics of the pump are such that it is particularly suited for use wherever sanitary conditions should prevail. It is constituted of few parts which are capable of being quickly separated for cleaning purposes and can be reassembled easily without the need of special tools.

In general, the pump includes a single rotor which rotates in a circular chamber within a casing having inlet and outlet passages communicating with the chamber. The rotor provides two impellers, each consisting of two similar lobes rotatable in the circular chamber and having the lobes of the respective impellers located in a phase relationship of 90 whereby the combined pumping actions of the impellers produce a substantially uniform ow of uid from the pump. The side walls of the circular chamber are closed by end plates which are detachably associated with the body of the casing which contains the circular chamber, and the rotor is so mounted on the rotor `shaft as to allow self-positioning or floating of the rotor axially on the shaft and the minimizing of drag on the rotor and end thrust on the rotor and the shaft that might otherwise develop.

The two pumping sections within the circular charnber, as defined by the individual impellers, are separated from each other by a wall formed in part by adjacent ends of the respective impellers and in part by the material of the rotor between the lobes of the respective impellers and which provides an outer peripheral edge surface contiguous to the cylindrical surface of the circular chamber.

The inlet and outlet passages are respectively common to the two sections. Each pumping section includes a movable sealing member between the high and low sides of the section which rides on and is spring-pressed against its associated impeller and slides in close engagement with a partition separating the inlet and outlet passages as it is oscillated by a rotating impeller. Other objects involve novel features and combinations of parts, the essential elements of which are set forth in the appended claims and a preferred form or embodiment of which is described hereinafter with reference to the drawing which accompanies and forms part of the specification. l j v In the drawing, Fig. 1 is a vertical section through :the axis of a pump;

Fig. 2 is an end view of a pump rotor; Fig. 3 is a section on line 3-3 of Fig. 2;

Fig. 4 is a vertical view along lines 4-4 of Fig. l showing sections taken on two parallel planes;

Fig. 5 is a section showing details on line S-S of Fig. 4;

Fig. 6 is a horizontal section on line 6 6 of Fig. 4;

` Fig. 7 is a sectional view on line 7-7 of Fig. 4; and

2,882,828 Patented Apr. 21, 1959 ice Fig. 8 is a fragmentary detail section of a modied form of a rotor shaft and end plate.

Referring to the drawing, the pump 10 is supported on and removable from the base 11 in which a thrust bearing 12 and a needle bearing 13 are mounted for rotatably supporting the shaft 14. The accessible end of the thrust bearing 12 is covered by a plate 15 which is fastened to the base 11 by a plurality of screws. The shaft 14 is driven by a gear or pulley 16 which is fixed on the shaft 14. The base 11 carries a face plate 17 to which the pump 10 is removably attached and from which the pump may be removed for servicing and cleaning.

The pump casing is constituted of three separable members including a central body 18 having a cylindrical bore 19 which constitutes a circular chamber, and two end plates 20 and 21 which provide walls for the opposite ends of the circular chamber. The circular chamber is concentric with the axis of the shaft 14.

The pump body 18 and the end plate 20 are aligned with the face plate 17 by a pair of dowel pins 22 and 23 engaged in aligned holes in these three members. The end plate 21 is justified with respect to the body 18 by another pair of dowel pins 24, 25, engaged in registering holes in the body and the end plate, respectively. All of these pins are parallel to the shaft 14 and enable axial separation of the respective members of the casing for dismantling purposes.

The pump casing is mounted on pins or rods in the form of studs 26, 27, 28 and 29 (Fig. 4), which are screwed into the face plate 17 and extend parallel to the shaft through registering holes in the end plates and pump body. The pump casing and assembled parts are held firmly in place on the base by the studs and the wing nuts 30 threaded onto the ends of the studs and engaging the end plate 21. The arrangement is such that access may readily be had to the interior of the casing by simply removing the wing nuts and the end plate 21 and any or all of the parts of the pump casing and slipping them out from the studs.

The end plates 20, 21 contain circular grooves 31 and 32, respectively, for receiving O-rings for sealing between the end plates and the pump body 18. The end plate 20 is also grooved to receive an O-ring 33 to seal around the shaft 14.

The inner surfaces of the end plates and the facing surfaces of the pump body are parallel and the width of the rotor 34 is commensurate with or may be slightly less than the axial dimension of the circular chamber 19. In any casevthe rotor is so mounted on the supporting shaft 14 as to be loose for axial floating on the shaft. Its inner bore has a groove 35 throughout its length to slidingly engage a key 36 which is fixed in the cylindrical portion 37 of the shaft 14 which is engaged with the bore. One end of the cylindrical portion 37 of the shaft extends to a shoulder 38 located within the end plate 20, and the other end terminates just short of the inner wall surface of the end plate 21 so that except for the end plates the rotor is` free for axial movement. Accordingly, the rotor is hydraulically balanced endwise by the iluid being circulated by the pump. It can be easily withdrawn from the shaft when the end plate 21 is removed.

The rotor is formed in one piece and comprises two impellers 39 and 40 arranged side by side and out of phase crcumferentially around the shaft so as to provide a substantially uniform rate of flow of uid through the pump.

Each impeller has two diametrically opposite lobes and the lobes of one impeller are located in a phase relationship to the lobes of the other impeller. The maximum diameter on the major axis of each impeller corresponds with the diameter of the cylindrical surface of the circular chamber 19 in the body 18. Intermediate the lobes of the impellers 39 and 40,l the material of the rotor extends circumferentially around the rotor and provides a dividing wall 41 with an outer peripheral edge having a diameter equal to the maximum diameter of the rotor whereby the pressure and suction strokes of one impellerV are effected independently of the suction and pressure strokes, respectively, of the other impeller.

The body 18 is provided with an inlet passage 42 and an outlet passage 43 which communicate with the circular chamber 19 at either side of a dividing wall or partition 44, Fig. 4, between the passages. These passages gradually widen to the approximate width of the circular chamber 19. The impellers serve as cams for oscillating arms 45 and 46 carrying movable partitions or vanes 47 and 48, respectively. The arms are pivotally mounted on a shaft 49. The shaft is journalled in openings in the end plates 20 and 21, Fig. 5. The arms are located in a space 50 within the body 18 and in communication with the outlet passage 43. The dividing wall 44 and the space 50 extend to the inner surfaces of the end plates 20 and 21.

Each of the arms and moving partitions have an outer surface concentric to the axis of rotation of the arm and closely fitting with and slidable over a surface 51 of corresponding curvature on the wall 44.

As best seen in Figs. 1 and 5, the movable partition 47 corresponds in width to the impeller 39 and the movable partition 48 corresponds in width` to the impeller 40 and the two partitions are separated by the material of the rotor which extends disk-like to the cylindrical surface 19 of the Circular chamber, so that each arm and movable partition cooperates with its associated impeller independently of the action of the other arm and movable partition. The hubs of the respective arms 4S and 46 are extended to slidingly contact each other, as shown in Fig. 5.

The arms are spring-urged to contact the movable partitions with the peripheries of the impellers 39 and 40. As shown in Fig. 4, a spring-pressed pin 53 is slidingly supported in a bearing S4 in the casing and in an adjustable nut 55. The spring 56 is tensioned between the nut 55 and a washer 57 which bears against a shoulder on the pin 53. The tension in the spring for continuously maintaining the nose of the movable partition 47 on the periphery of the impeller 39 may be adjusted by rotating the nut.

The spring 56 is contained in a recess in the body 18 outside of the hollow interior of the pump and which is sealed from the space 50l by an O-ring 58 so that the uid within the pump is not agitated by the action of the spring. The arm-engaging end of the pin is rounded and rests against the surface of a shallow recess extending along the central axis of the arm. The pin 59 and spring for the other arm 46 are similarly arranged. 'Ihe spring-containing recesses are so located within the body 18 as to contribute to a pump of economical over-all pro portions.

The contours of the impellers are alike. Each lobe is preferably shaped to give simple harmonic motion to the movable partition between limits of oscillating move ments ofthe arms 45 and 46, or a close approximation of harmonic motion. It is unnecessary to set forth herein details concerning the relationship of the oscillating arm to the impeller and the shape of the cam surface of an impeller as these matters are fully explained in the United States Patent No. 2,717,555. It is apparent, however, that in view of the facility with which the rotor maybe withdrawn from the shaft, rotors with impellers having other contours may be readily substituted.

A relief valve 61 is slidably mounted in a bore in the body 18. 'Ihe lower end of the valve is taperedf and normally extends across a passage 62.` between the space 50r and the intake passage 42. Valve 61 is an enlarged part of a pin 63 which slides through an opening in `a nut 64 engaged by threads interiorly of a bore 65. A

washer 66 seats against the shoulder of the valve and a spring is tensioned between the washer and the nut 64. The spring tension is so adjusted that the valve will be relieved whenever the pressure on the discharge side of the pump exceeds a desired limit which is determined by the position of the nut 64. An O-ring 67 is contained in a groove surrounding the valve for preventing leakage of fluid along the valve.

An important-.featureof the pump described is its. moderate manufacturing cost and its adaptability for use wherever the maintenance of sanitary conditions is requisite. The shaft is wholly supported on a base and outside of the pump casing so that no bearings are required in the end plates of the casing. The shaft freely passes through a hole in one of the end plates and the other end plate is plain and is dat adjacent the outer end of the shaft. Moreover, all planes of separation accessible to the interior of the pump are sealed with gaskets which are effective for preventing loss of pressure or leakage of uid and are so. located as to be readily accessible for removal for cleaning purposes when the pump is dismantled.

While economy in manufacturing costs is desirable, some uses require higher operating pressures. These may be` attained in a pumpv having most of the desired physical characteristics described hereinabove by substituting a longer shaft and an outboard bearing. The only changes required are illustrated in Fig. 8 in which the end plate 20,.the body 18 and the. rotor 34 are the same as previous- 1y described but the shaft and the outboard end plates are different. The reduced portion 70 of the shaft 71 has a length commensurate with the width of the rotor 34 and the shaft is extended to receive a locking nut 72 and to provide an end 73 extending through a bearing 74. The end plate 75 has a hollow boss 76 supporting the bearing, and the shaft is preferably sealed at the open end of the boss by an O-ring 77, but if desired the, open end of the boss may be closed over the outboard end of the shaft. A carbon-graphite bearing is preferred. With any end plate having a bearing for the outboard end of the shaft the lower pair of wing nuts are replaced by wing nuts 78 having longer Shanks as the same studs 28 and 29 are employed.

The pump is suitedv for use Wherever sanitary conditions are requisite, as for transferring foods such as milk, juices, Syrups, and more viscous materials, such as chocolate, preserves, catsup, mayonnaise, and other owable mixtures. Dismantling or assembling is readily accomplished without special skill and all parts, including the O-ring gaskets, are easily accessible for cleaning.

While the form of mechanism herein shown and described is admirably adapted to fulfill the objects primarilyy stated, it is to be understood that it is not intended to confine the invention to the one form of embodiment herein disclosed, for it is susceptible. of embodiment in various forms all coming within the scope of the claims which follow.

What is claimed is:

l. A pump of thel character described, comprising a body having a circular pump chamber and inlet and outlet passages connecting with said chamber and separated by a partition extending inwardly to the circular periphery of said chamber, end plates providing walls square to the axis of said chamber for closing the ends, of said circular chamber, means detachably securing said end plates to said body, a shaft extending through at least one of said end plates and the radial center of said circular chamber, a rotor mounted on said shaft, said rotorconstituting a unitary member comprising two impellers spaced axially from each other lengthwise of said shaft with the opposite sides of said rotor parallel to and adjacent the respective walls of said end plates at the ends of said chamber, each of said impellers havingy two lobes providing outer surfaces with portions thereof in sweeping relationship contiguous to the circular wall of Asaid chamber at diametrically opposite sides of the axis of said shaft and chamber, the lobes of one impeller located in 90 phase relationship with the lobes of the other impeller, the material of said rotor forming a wall normal to the axis of said shaft centrally between said impellers, said central wall having an outer circular periphery contiguous to the circular wall of said chamber and thereby providing a barrier integral with said impellers and separating the pumping sections of the respective impellers from one another, and a spring-urged sealing member for each impeller, each sealing member having a nose riding on its associated impeller.

2. A pump of the character described, comprising a drive shaft, a base for supporting said drive shaft, a casing including a body having a circular pump chamber and an end plate at either end of saidbody, said end plates providing dat walls normal to the axis of said chamber and closing the ends of said chamber, one of said end plates having an opening for the passage of said drive shaft therethrough and through the radial center of said circular chamber, said body having inlet and outlet passages communicating with said circular chamber and separated by a partitionextending inwardly to the outer circular periphery of said circular chamber, meansvsupporting said casing on said base, saidlsupporting means comprising rods disposed parallel to said shaft and engaged in holes in said base, said body and said end plates, manipulatable members for clamping said body and end plates in assembled relationship on said rods, a rotor having end faces normal to the axis of said pump chamber, said rotor having a width as measured between said end faces substantially equal to and no greater than the length of said circular chamber as defined by'the axial space between said end plates, means non-rotatably supporting said rotor on said shaft but allowing axial floating of the rotor on said shaft except as restrained by said end plates, said rotor constituting a unitary member comprising two impellers having lobes providing outer surfaces with portions thereof contiguous and in sweeping relationship to the circular wall of said chamber and axially separated by a wall normal to the axis of said shaft centrally between said impellers whereby said circular pump chamber is divided into two pumping sections with an impeller in each section, and a movable sealing member riding on each impeller and separating the high and low pressure sides of the impeller.

3. A pump of the character described, comprising a drive shaft, a base, bearings mounted on said base for supporting said drive shaft, a casing including a body having a circular pump chamber and an end plate at either end of said body, one of said end plates having an opening for the passage of said drive shaft and the other of said end plates providing a closed wall disposed opposite the free end of said shaft and closing the end of a circular chamber in said body, said body having inlet and outlet passages entering from opposite sides of the body and communicating with said circular chamber and separated by a partition extending inwardly to the outer peripheral surface of said circular chamber, means detachably supporting said casing on said base whereby said casing may be removed from around the free end of said shaft without disturbing the mounting of said shaft in said bearing, said supporting means comprising rods disposed parallel to said shaft and engaged in holes in said base, said body and said end plates, means for clamping said body and end plates in assembled relationship on said rods, a rotor, said rotor constituting a unitary member having a width substantially equal to and no greater than the axial length of said circular chamber, means nonrotatably supporting said rotor on said shaft but allowing axial oating of the rotor on said shaft except as restrained by said end plates, said rotor comprising two impellers having lobes providing outer surfaces with portions thereof contiguous and in sweeping relationship to the circular wall of said chamber, said rotor having a ravdial'wall integral with and between' said impellers Withxa circular outer periphery on'a radius corresponding with the maximum radius of said lobes, said integralwall'dividing said circular pump chamber into two pumping sections with one of said impellers located in onel section and the other of said impellers located in the other section, and a movable sealing member riding on eachy impeller and separating the high and low pressure sides of its associated impeller.

4. A pump of the character described, comprising a drive shaft, a base for supporting said drive shaft, a` casing including a body having a circular pump chamber and an end plate at either end of said body detachably secured to said body, said end plates providing flat walls normal to the axis of said pump chamber .and closing the ends of said pump chamber, one of said end plates having an opening for the passage of a drive shaft therethrough and through the radial center of said chamber, a plurality of pins engaged in holes in said end plates and body, said pins and holes parallel to said shaft, said body having inlet and outlet passages connecting with rsaid circular chamber and separated by a partition extending inwardly to the outer circular periphery of said circular chamber, means supporting said casing on said base, a rotor, said rotor having end'faces normal to the axis of said pump chamber and a width as measured between said end faces substantially equal to and no greater than the axial length of said circular chamber, means non-rotatably supporting said rotor on said shaft'but allowing axial floating of the rotor on said shaft except as restrained by said end plates, said rotor constituting a unitary member comprising two impellers having lobes providing outer surfaces with portions thereof contiguous and in sweeping relationship to the circular'wall of said chamber and separated by a wall normal to the axis of said shaft centrally between said impellers whereby .said pump chamber is divided into two pumping sectionswith an impeller'in each section, said wall having an outer circular periphery on a radius corresponding with the maximum radius of said lobes, a pivoted arm for each impeller, each arm having at its free end a sealing member bearing on its associated impeller, a pivot shaft for said arms, said pivot shaft extending in holes in each of said end plates and spring-urged rods slidably mounted in said body and engaging said arms for pressing said sealing members into contact with the surfaces of said impellers.

5. A pump of the class described, comprising a drive shaft, a base rotatably supporting said shaft, said shaft having an end overhanging said base, a casing enclosing said overhanging end of said shaft, said casing including a body having a circular pump chamber concentric with the axis of said shaft, a wall closing one end of said circular chamber and having an opening for the passage of said shaft therethrough, and a second wall disposed opposite the terminus of said overhanging shaft end and closing the other end of said circular chamber, said body having inlet and outlet passages connecting with said circular chamber and separated by a partition extending inwardly to the circular surface of said chamber, a rotor axially slidable Iand non-rotatably mounted on said overhanging end of said shaft so as to enable said rotor to assume a neutral position centrally between said first and second-named Walls under the influence of hydraulic pressure between the respective ends of the rotor and said walls, said rotor having lobes for advancing material through said circular chamber from said inlet passage to said outlet passage, sealing means constantly riding on said lobes and separating the high and low pressure sides of said circular chamber at opposite sides of said partition, means for aligning said body and said end plates, said aligning means comprising pins registering in holes in said body and end walls, rods supported by said base and extending through said body and said end plates, and manipulative members attached to said rods and said second wall whereby upon removal of said manipulatable members'` said: secondi wall maybel removed for gaining access: for the removal of: said rotor over the terminus of theoverhanging end of said shaft..

6. A pump of the character described, comprising a body,v having 'a circular chamber and inlet and outlet passages connecting with said chamber and separated from each other by a partition, said body having an open space' opening into said circular chamber and into said outlet passage and a third passage connecting saidv space with` said` inlet passage, a valve slidable in ya bore, intersecting said third passage. and extending through a wal-l of said body to a recess opening outwardly of said body, said' valve having a stern extending into said recess in said body and 'a closure slidableA in said bore and normally closing said third passage, said recess containing means for resiliently4 urging said valve into closed position across said third passage, an end Wall fastened to each of the ends of saidv body andclosing the ends of said circular chamber and of. said open space, a shaft extending through at least one of said end walls and the radial center of said circular chamber, a rotor mounted on said shaft, said rotor comprising two impellers with a wall therebetween having a circular outer periphery contiguous, to the circular periphery of saidv chamber, each of said impellers having. two lobes providing outer surfaces with portions -thereof in sweeping relationship contiguous to the circular periphery of said chamber, a pivot shaft extending through said space in said body and supported at its ends in said end walls, an arm for each impeller, said arms pivotally mounted on `said pivot shaft and each arm having a nose contacting its associa-tedimpeller, each arm engaged by a pin slidablyY mounted in a bore in said body and extending through a nut engaged in a` recess in said, body, and means contained in said recess for exerting resilient force on said pin. and said arm to maintain the. nose of said arm in contact with its associated impeller.

7. A pump of the character described, comprising a casing including a body having a circular chamber and an end plate at either end of said body providing parallel end walls for the ends of said circular chamber, said bodyy having inlet land outlet passages` separately commllncating With Saidv circular chamber at oppositey sides `of 'an axially disposed partition fixed -to said body and extending inwardly to the periphery of said circular chamber, Aa shaft extending; through the radial center of said circular chamber, a base rotatably mounting said shaft, said base having a face plate normal to the .axis of said shaft, 'a plurality of pins registering in holes in said face plate and in said end plates and body members of said casing parallel to the axis of said shaft whereby adjacent members of said casing lmay be separated from lone another in the longitudinal direction of said axis, means for clamping said casing to said face plate, a rotor contained in said circular chamber 'and keyed to said shaft for rotation therewith, said rotor comprising a single member substantially as wide as the length of said circular chamber and consisting of two two-lobe impellers and a wall separating said impellers,A said wall having a circular periphery contiguous to the circular wall of said chamber and dividing said circular chamber into two pumping sections with one of said impellers in one section and the second of said impellers in the other section, a pivoted arm for each impeller, each 'arm having on its free end asealing member bearing on its associated impeller, an arm pivot shaft seated in said end plates, and springurged rods slidably mounted in said body and pressing said arms towards said impellers and said sealing members in contact with said impellers.

References Cited in the tile of this patent UNITED STATES PATENTS 16,875. Griswold Mar. 24, 1857 564,080 Keeler July 14, 1896 1,698,815 Jaworowski Ian. 15, 1929 1,787,708 Teesdale Jan. 6, 1931 1,902,076 Jaworowski Mar. 21, 1933 2,013,397 Balsiger Sept. 3, 1935 2,384,286 Dowling Sept. 4, 1945 2,583,633. Cronin Ian. 29, 1952 2,609,754 Prendergast et al Sept. 9, 1952 2,717,555 Hinckley Sept. 13, 1955

Patent Citations
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US564080 *Jul 17, 1895Jul 14, 1896F Onewilliam p
US1698815 *Apr 29, 1924Jan 15, 1929Jaworowski Joseph FDuplex rotary pump
US1787708 *Sep 7, 1928Jan 6, 1931Teesdale John BRotary pump
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US2013397 *Aug 26, 1930Sep 3, 1935Landis Tool CoHydraulic motor and method for making the same
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3240157 *Dec 12, 1961Mar 15, 1966Hinckley John NRotary pumps
US3307488 *Oct 23, 1965Mar 7, 1967Hinckley John NPositive displacement rotary pumps
US7794591Mar 21, 2008Sep 14, 2010Zodiac Pool Systems, Inc.Pool filter
US7815796Dec 31, 2007Oct 19, 2010Zodiac Pool Systems, Inc.Pool filter
US7951293Oct 6, 2008May 31, 2011Zodiac Pool Systems, Inc.Methods and apparatus for a pool treatment and water system
US8137545Sep 13, 2010Mar 20, 2012Zodiac Pool Systems, Inc.Pool filter
US8173011May 31, 2011May 8, 2012Zodiac Pool Systems, Inc.Methods and apparatus for a pool treatment and water system
US8516661Apr 29, 2009Aug 27, 2013Zodiac Pool Systems, Inc.Retainer band for use in fluid-handling vessels
Classifications
U.S. Classification417/310, 418/248, 417/311, 418/70, 418/215
International ClassificationF04C2/00, F04C2/46
Cooperative ClassificationF04C2/46
European ClassificationF04C2/46