US3240155A

US3240155A - Helical rotary pumps

Info

Publication number: US3240155A
Application number: US432041A
Authority: US
Inventors: Quiroz Francisco Angel
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-01-21
Filing date: 1965-01-21
Publication date: 1966-03-15
Anticipated expiration: 1983-03-15

Description

March 15, 1966 F. A. QUIROZ HELIGAL ROTARY PUMPS Original Filed March 22, 1962 2 Sheets-Sheet l INVENTOR. FAANciscn A Qw'noz [I ,4 (VI/M01,

March 15, 1966 F. A. QUlROZ HELICAL ROTARY PUMPS 2 Sheets-Sheet 2 Original Filed March 22, 1962 VA 10 a:

IN VEN TOR. lkAh/ziito A Quinn: r? /7 fwkvz United States Patent 7 Claims. (Cl. 103-117) This application is a continuation of patent application Serial No. 181,553, filed March 22, 1962, now abandoned.

This invention relates to rotary pumps having helical impeller means.

Helical rotary pumps are designed to pump fluids (usually liquids) longitudinally, i.e., parallel to the axis of rotation. A type is known in which the rotor supporting the impeller means is mounted eccentrically with respect to the surrounding housing so that the fluid being pumped does not acquire a rotational velocity component instead of the desired longitudinal component. In such a pump the peripheral surface of the rotor and the inside Wall of the housing are mutually tangential along a locus parallel to their respective axes, which are spaced from one another to an extent determined by the degree of eccentricity. Pumps of this type have not proved satisfactory at high speeds or high pressures but have remained principally a sort of laboratory curiosity suitable, if at all, only for trivial applications where other pumps could do as well or better.

A primary object of the present invention is provision of a design of helical rotary pump operative at high pressures and high pumping speeds.

Another object is provision of a multi-purpose pump of helical rotary type characterized by extremely high efficiency throughout a wide range of pumping pressures and speeds and suitable for a wide variety of applications.

A further object is provision of such a pump, simple and inexpensive in construction and efficient and dependable in operation, for use in a deep well, as for pumping water for irrigation purposes.

Other objects of this invention, together with means and methods for attaining the various objects, will be apparent from the following description and the accompanying diagrams.

FIG. 1 is a longitudinal section, part of the interior elements being shown in side elevation, of a pump according to the present invention;

FIG. 2 is a transverse section of the same pump taken at 22 on FIG. 1;

FIG. 3 is an end elevation of a disc component of the rotor of the pump shown in the preceding views;

FIG. 4 is a side elevation of the disc shown in end elevation in FIG. 3;

FIG. 5 is an end elevation of an impeller element of the same pump; and

FIG. 6 is a side elevation of the impeller element shown in end elevation in FIG. 5.

FIG. 7 is a view, partly in side elevation and partly in longitudinal section, of another pump according to this invention installed in a well casing and with drive means attached;

FIG. 8 is a view, also partly in side elevation and partly in section, of another pump of this invention together with drive means; and

FIG. 9 is a fragmentary view, partly in top plan and partly in longitudinal section, of yet another pump of this invention.

In general, the objects of the present invention are accomplished, in a helical rotary pump, by means of a cylindrical rotor grooved on its peripheral surface to accommodate impeller elements for radially reciprocating and 3,240,155 Patented Mar. 15, 1966 ice laterally swivelling movement therein, following a generally helical configuration from one end of the rotor to the opposite end, with adjacent impeller elements therein partially overlapping one another laterally. As can be visualized from the illustrations, in certain of which the impeller elements are shown in place and in other of which they are shown apart, the grooving of the rotor follows a sort of zig-zag path from one end of the rotor to the other. The rotor itself is conveniently formed of appropriately desegmented discs assembled face to face on a common axis but with the desegmented portions of mutually adjacent discs oriented at a given difference in rotational angle but partially overlapping to provide the continuous Zig-zagging grooving of the rotor surface and consequent lateral overlapping of the impeller elements assembled therein.

FIG. 1 shows a pump constructed according to the present invention. Casing or housing 20, which is generally cylindrical in configuration, has terminal flanges 21 and 22 at the left and right, respectively, whereby it is secured by bolts 49 to a pair of end chambers 44, each having at one end flange 45 and at the other end internally threaded opening 46 for connection to pipes or the like (not shown in this view). Each end chamber has hearing sleeve 46a supported coaxially therein by a number of spoke-like ribs 48 extending from the inside wall of the chamber and enclosing bushing 47, thereby forming right and left bearings in the respective chambers to accommodate rotor shaft 26, the right end of which has a reduced threaded portion protruding from the end chamber. Although coaxial with the end chambers the rotor shaft is not coaxial with housing 20 but is offset parallel to the housing axis by virtue of eccentricity of flanges 45 of end chambers 44.

Secured to rotor shaft 26 by

tapered pins

30 and 31 are

respective head plates

28 and 29, one being shown in elevation and one in diametric section in FIG. 1, and each being provided with pair of openings 34, 35 therethrough flanking the bore for the rotor shaft. Retained between the head plates are rotor discs 30 (thirteen in number) all of uniform diameter smaller than the inside diameter of the housing and each of which is bored axially to receive the rotor shaft and is secured thereto by key 27. As shown more clearly in the respective end (with respect to the axis) and side elevational views of FIGS. 3 and 4, each rotor disc is cut away or desegrnented at opposite sides. The location of key way 52 in the discs ditfers by about half a right angle in each adjacent pair of discs so that the desegmented portions of adjacent discs are offset circumferentially by such an angle from one another although still overlapping somewhat. The respective lateral edges of opposite desegmented

portions

41 and 42 of each rotor disc 32 slant obliquely in opposite directions, the two oblique side edges of each desegmented portion being flat and parallel to one another and substantially perpendicular to the corresponding edges of the opposite desegmented portion of the same disc. The inner edge of each desegmented portion curves about the axial bore (spaced therefrom) more or less parallel to the arcuate peripheral surface that would have completed the desegmented portion of the disc if it had not been recessed or cut away.

The peripheral surface of rotor 25 made up of these discs is characterized by two equally spaced, generally helical grooves, cor-responding to the desegmentation of the component discs, extending from one end of the rotor to the other in a sequence of interconnecting alternately circumferential and oblique portions, the former being longer than the latter. Housing 20 is channeled internally from end to end along the bottom portion thereof, and bearing bar 24, which is suitably formed by machining or otherwise, fits into channel 23 so provided to complete the cylindrical housing wall. The pump mounting, described above, is sufficiently eccentric to bring the peripheral surface of the rotor and the inside wall of the housing, as supplemented by the bearing bar, into contact with one another along a line of mutual tangency parallel to the respective axes of the rotor and the housing, and fine adjustment is provided by set screws 51 threaded through boss 50 on the bottom portion of flanges 21, 22 of end chambers 44 and bearing against the outside surface of channeled porttion 23 of housing 20.

Each desegmented portion of each disc 32 composing the rotor accommodates a separate impeller element 33, each such impeller element having a rhomboid transverse cross section, having arcuate peripheral surface 33c with a radius of curvature matching the radius of curvature of the inside Wall of housing 20, and having an inner surface curved like that of the inner edge of the desegmented portion of the disc. FIGS. and 6 show an impeller element in end (with respect to the rotor axis) elevation and in peripheral side elevation, respectively, apart from the rest of the apparatus, while FIGS. 1 and 2 show such impeller elements assembled into the desegmented portions of the discs composing the rotor. Each impeller element has the same thickness (in the axial direction) as the disc that accommodates it, the wide flat surfaces of the impeller elements fitting flush with the flat faces of the discs. Opposite oblique side edges 33d, 33e of each impeller element are convexly arcuate, and their separation or the width of the element is such that the element fits closely against the oblique walls of the desegmented portion of the disc so that the element can pivot or swivel laterally as well as sliding radially with respect to the disc. The impeller elements may have heavy in-; serts 44 therein to aid maintenance of contact with the housing wall under the influence of centrifugal force as the rotor rotates. Rotation in the direction indicated by curved arrow 111 (FIG. 1) at the threaded end of the rotor shaft impels fluid through the pump in the longitudinal direction indicated by the horizontal arrows. The oblique straight arrows indicate the helix direction of the impellers composed of the impeller elements.

When an impeller element has slid inwardly until its peripheral surface is flush with that of the disc, as it must at the bottom of the housing where the rotor surface and housing wall are mutually tangential, the element occupies essentially all of the desegmented portion of the disc; however, when the element is further outward, having been forced outward by centrifugal force upon rotation of the rotor, an opening 32 is formed between the curved inner edges of the element and the desegmented portion of the accommodating disc, as shown in the instance of end impeller elements 33a shown in longitudinal section in FIG. 1 adjacent right end plate 29 (similarly shown) which has openings 34, 35 therethrough to receive fluid expelled from such opening 32 as the impeller element is forced back inwardly upon continued rotation of the rotor.

It will be apparent that two helical rows 39, 40 of impeller elements occupy the double grooving of the rotor surface corresponding to the double desegmentation of the component discs of the rotor, and that the rotation of the rotor wipes them along the inside wall of the housing to drive the fluid in the pump longitudinally from one end to the other through the pump. Regardless of the degree of exposure of the impeller elements each helical impeller line is continuous because of the lateral overlap of the component impeller elements and is sealed against the inside wall of the housing because the peripheral surface-s of the impeller elements, which match it in curvature, swivel to provide maximum contact therewith under the influence of the centrifugal force provided by rotation of the rotor.

Because of the tangential contact of the rotor with the portion of the inside wall of the housing provided by the bearing bar, the fluid being pumped cannot circulate circumferentially but must pass longitudinally through the pump. The fluid is confined to a pair of intertwining helical configurations provided between the double line of laterally over-lapping impeller elements in contact with the inside wall of the housing. While only one helical line of impeller elements could be used, it not only would be unbalanced but more (or wider) elements to provide at least two complete turns of the helix would be required to trap and seal the fluid for pumping, whereas with the double-line impeller illustrated and described above, good dynamic balance is attained and only one and one-half turns are required to trap and seal the liquid against "backflow o-r pumping leakage. Three or more helical impellers, evenly spaced circumferentially from one another, could be used, whereupon fewer turns would be required for effective sealing and pumping.

The pump of this invention may be constructed of steel or other suitable metal throughout, but the bearing bar and impeller elements preferably are made of resilient plastic bearing material, especially when water is the fluid to be pumped because water is an excellent lubricant for such material. The inside wall of the housing preferably is chromed and polished to reduce friction and to withstand wear and resist corrosion.

It will be noted that each of the impeller elements not only slides circumferentially at its peripheral surface along the inside wall of the housing and radially (and swivels) at its side edges along the side edges of the rotor discs accommodating it, but also radially (and swivels) at its flat faces along the faces of the adjacent rotor discs, lubricated in each instance, of course, by the fluid being pumped. Of particular importance is the fact that the reactive thrust of the fluid against the impellers is taken up principally, as to each impeller element, by an adjacent rotor disc against which it slides, rather than being transmitted from element to element of each impeller to jam one or more of such elements as the thrust accumulation thereon becomes excessive. The minor lateral overlap of adjacent impeller elements provides the pump of the present invention with the desired sealing continuity of the impeller(s) while permitting smooth and dependable high-speed and high-pressure operation. The pump will operate in either flow direction by reversing the direction of rotation of the rotor.

FIG. 7 shows, partly in side elevation and partly in iongitudinal section, a pump constructed essentially as in the preceding views and set up for deep well pumping in much the manner of a multi-stage centrifugal deep-well pump. Well casing surrounds pump unit 104, together with d scharge pipe at its upper end (the right side in this view) and intake pipe 108 and attached check valve and strainer assembly 109 at the opposite end. One end 106 of the discharge pipe is connected to the threaded portion of one end chamber of the pump, while other end 107 is threaded into discharge head casting 102, which supports not only the pump and previously mentioned elements inside the well casing but also motor 103 located outside, the motor shaft being interconnected by shaft 110 to the rotor shaft of the pump by Way of the passage provided by the discharge pipe and the accommodating opening therefor in the discharge head casting. Interconnecting shaft 110 is supported by a thrust bearing (not shown) in the motor to maintain the desired rotor position under the reactive thrust of the fluid (here most likely water) being pumped, the shaft being rotated counter-clockwise (viewed down the well, to the left in this view) and the discharge being as indicated by the arrow shown in the open-flange end of the discharge head casting.

FIG. 8 shows, partly in side elevation and partly in longitudinal section, an industrial installation of a pump constructed essentially as shown in FIG. 1 and immediately succeeding views. Casing or housing 20 is provided with modified

end chambers

112 and 113 having mounting

legs

114 and 115, respectively. The end chambers have ball bearings 116 for the shaft of rotor 25 and shaft seals 117 and have inlet port 118 and outlet port 119 (partly obscured) in the respective chambers. Adjusting

screws

120 and 121 through the flanges of the respective end chambers provide the desired adjustment of rotor orientation for sealing contact along the line of tangency with hearing bar 24.

FIG. 9 shows, partly in top plan and partly in elevation, a pump constmcted according to the present invention but hydraulically balanced by having two rotors with impellers of opposite hand mounted on a common shaft. Housing 135) has eccentric cylindrical portions a and 2012 at the left and right, respectively, with coaxial rotors a and 25b carried on common shaft 26 so as to contact respective bearing bars 24a and 24b located at the forward edge of the inside wall of left cylindrical housing portion 20a and at the rear edge of the inside wall of right cylindrical housing portion 2012. Housing 130 has inlet 131 at the rear branching into left and right channels 132 and 133, which proceed to the opposite ends (not shown) of the respective cylindrical housing portions, and outlet 136 at the front. The helical impellers are left-handed on the left rotor and right-handed on the right rotor so that when the shaft rotates as indicated by curved arrow 135, the direction of flow is into the inlet and out of the outlet as indicated by the straight arrows. The axial thrusts of the respective rotor impellers are equal and opposite and, therefore, neutralize one another, while the radial thrusts are opposed to one another and, being largely localized near the center point of the shaft between the rotors, are also substantially neutralized; the remaining unneutralized portions of the radial thrusts, which generate a torque about the center of the shaft, are taken up by the bearing bars located on opposite sides in the respective cylindrical housing portions.

There are many factors that affect or contribute to the capacity of pumps constructed according to the present invention, including pitch of the helical impellers and their number of turns, rotational speed of the rotors carrying the impellers and the weight of the impeller elements, the diameters and eccentricity of the rotor and the surrounding casing or housing. Inasmuch as many embodiments of the invention are possible in addition to those illustrated and described above, such illustration and description is by way of example, rather than limiting, the invention being defined in the following claims.

The claimed invention:

1. In a pump, a cylindrical housing, a cylindrical rotor of lesser diameter therein, the housing and the rotor meeting along a line of mutual tangency, the rotor having in its cylindrical surface a pair of zigzagging helical grooves diametrically opposite one another, each groove :being comprised of successive interconnecting groove portions oriented alternately oblique and perpendicular with respect to the axial direction, and impeller elements movable radially fitting into the grooves, each perpendicular portion of each groove being occupied together with essentially half of each of the adjacent oblique portions thereof by a single impeller element, the adjacent faces of each pair of adjoining impeller elements being in partially overlapping contact with one another, and the peripheral surface of each impeller element having curvature matching that of the cylindrical housing so as to fit thereagainst.

2. In a pump, a cylindrical housing, a cylindrical rotor of lesser diameter therein, the housing and the rotor meeting along a line of mutual tangency, the rotor having an axial shaft and a multiplicity of identical disclike components secured on the shaft, each disclike component being cut out from its peripheral edge and its opposing faces corresponding to removal therefrom of a segment having its lateral edges slanted obliquely and parallel to one another, adjacent recesses in successive disclike components comprising a generally helical groove comprised of successive groove portions oriented alternately oblique and perpendicular with respect to the axial direction, and a multiplicity of impeller elements, successive impeller elements being displaced axially and circumferentially from but partially overlapping one another in a generally helical configuration, the respective impeller elements having fiat parallel faces flush with the opposing faces of the respective disclike components of the rotor and having their peripheral surface convex to fit the concave curvature of the cylindrical housing and having their lateral surfaces oblique with respect to the axis and matching the oblique slanting of the recessed lateral edges of the desegmented disclike components and having their lateral surfaces arcuately convex with a diameter corresponding to the width of the desegmentation, the impeller elements being free to slide radially therein to bring their peripheral surface into contact with the cylindrical housing and being also free to swivel laterally therein to establish and maintain sealing contact with the cylindrical housing during rotation of the rotor, adjacent impeller elements also fitting closely against one another to the extent of their mutual overlapping and fitting closely laterally in the desegmentation of their respective disclike components throughout all radial and swivelling movement with regard thereto.

3. In a pump, comprising in combination a cylindrical housing, a cylindrical rotor of lesser diameter rotatable and eccentrically mounted therein, the housing and the rotor in contact along a line of mutual tangency, the rotor having an axial shaft and a number of identical disclike components secured on the shaft, each disclike component having not less that two cut-outs from its peripheral edge equally spaced in order to have the disclike components dynamically balanced, each cut-out having its lateral edges slanted obliquely and parallel to one another, adjacent recesses in succesive disclike components overlapping one another to form a generally helical groove of successive groove portions oriented alternately oblique and perpendicular with respect to the axial direction, a number of successive impeller elements each one located in each cut-out of the disclike components displaced axially and circumferentially but partially overlapping one another in a generally helical configuration, having fiat parallel faces flush with the opposing faces of the respective disclike components of the rotor, and having their peripheral surface convex to, fit the concave curvature of the cylindrical housing and having their lateral surfaces oblique with respect to the axis of the rotor, and matching the oblique slanting of the recessed lateral edges of the disclike components, and having their outside lateral surfaces arcuately convex with a diameter corresponding to the width of the desegmentation, the impeller elements being free to slide radially therein to bring their peripheral surface into contact with the cylindrical housing, and being also free to swivel laterally therein to establish and maintain sealing contact with the cylindrical housing during rotation of the rotor, the adjacent impeller elements fitting closely against one another to the extent of their mutual overlapping, but free to slide against each other and in the desegmentation of their disclike components throughout all radial and swiveling movement, in order to make leakless lines of helical impellers.

4. In a pump as claimed in claim 3 in which the cutouts of the disclike components, have the bottom arcuately convex with a diameter corresponding to the distance from the bottom of the cut-outs to the center of rotation of the cylindrical rotor.

5. In a pump as claimed in claim 3 in which the impeller elements have their peripheral surface convex to fit the concave curvature of the cylindrical housing, and having a concave surface in the opposite side parallel to the convex surface and makes the concave surface with a slightly longer radius than the radius of the convex surface of the bottom of the cut-outs in the disclike components, in order to allow the impeller elements to swivel while they are all the way in contact with the bottom of the cut-outs in the disclike components.

6. In a pump as claimed in claim 3, in which the cylindrical rotor is provided with two end discs having the same diameter as the disclike components, in order to 5 support the end impeller elements in the proper position, the two end discs being provided with openings to allow the passage of the liquid being pumped in the helical grooves under the impeller elements.

7. In a pump as claimed in claim 3, in which the cy- 10 lindrical housing is provided along the line of mutual tangency between the rotor and the housing with a hearing bar of suitable material corresponding with the kind 1,495,526 5/1924 Phillips 103-136 1,550,931 8/1925 Ta'bler 10389 FOREIGN PATENTS 224,862 12/ 1924 Great Britain.

SAMUEL LEVINE, Primary Examiner. DONLEY I. STOCKING, Examiner.

Claims

1. IN A PUMP, A CYLINDRICAL HOUSING, A CYLINDRICAL ROTOR OF LESSER DIAMETER THEREIN, THE HOUSING AND THE ROTOR MEETING ALONG A LINE OF MUTUAL TANGENCY, THE ROTOR HAVING IN ITS CYLINDRICAL SURFACE A PAIR OF ZIGZAGGING HELICAL GROOVES DIAMETRICALLY OPPOSITE ONE ANOTHER, EACH GROOVE BEING COMPRISED OF SUCCESSIVE INTERCONNECTING GROOVE PORTIONS ORIENTED ALTERNATELY OBLIQUE AND PERPENDICULAR WITH RESPECT TO THE AXIAL DIRECTION, AND IMPELLER ELEMENTS MOVABLE, RADIALLY FITTING INTO THE GROOVES, EACH PERPENDICULAR PORTION OF EACH GROOVE BEING OCCUPIED TOGETHER WITH ESSENTIALLY HALF OF EACH OF THE ADJACENT OBLIQUE PORTIONS THEREOF BY A SINGLE IMPELLER ELEMENT, THE ADJACENT FACES OF EACH PAIR OF ADJOINING IMPELLER ELEMENTS BEING IN PARTIALLY OVERLAPPING CONTACT WITH ONE ANOTHER, AND THE PERIPHERAL SURFACE OF EACH IMPELLER ELEMENT HAVING CURVATURE MATCHING THAT OF THE CYLINDRICAL HOUSING SO AS TO FIT THEREAGAINST.