US1973669A - Rotary pump - Google Patents

Description

Patented Sept. ll, 1934 UNITED STATES ROTARY PUMP Willem Lodewijk Joost Spoor, Amsterdam, Netherlands Application February 6, 1933, Serial No. 655,528 In the Netherlands January 12, 1931v 4 Claims.

The invention relates to a rotary pump or compresser, more especially to the type of self-priming rotary pump for liquids, gases or mixtures of these fluids .and also known as liquid ring pumps.

The principal object of the invention is to provide a pump of this type which is much more efficient in operation than pumps of this class have been heretofore.

Another object of the invention is to provide a pump of this type in which relatively much higher pressures may be attained, without increasing however the working diameter of the rotor or increasing the circumferential speed.

Another object of the invention is to provide a construction of pumps of the kind mentioned, in which the normal flow of liquid, as it constitutes itself automatically within the pump, is affected as little as possible. Thus only vortices and Whirlings which are useful for the working of pumps will occur. In this manner also foaming of the liquid to be pumped, and forming of scum thereon is almost entirely avoided.

With these objects in View the invention consists broadly fin making the interior of the pump formed in such a manner that the liquid flowing therethrough is guided in a possibly unobstructed manner. To this end the walls of the cells formed between the vanes of the 'rotor viz. the walls opposite the guide passages arranged laterally of the rotor and each having two dead ends are curved near the periphery of the rotor and merge gradually into the side walls of the guide passages. Also other walls e. g. the side Walls of the said cells, i. e. the vanes of the rotor.

themselves may be curved or havesome bent form, while the movement of the liquid flowing through the pump may be supported also by special means especially provided therefor, such as cores. Furthermore, the measures in order to avoid the disadvantages for the pump construction arising from the strongly increased lift oi the pump which causes a much greater pressure than heretofore in pumps ofthis kind on the pump shaft, said pressure being directed radially from the outlet openings in the pump casing to the axis of the pump. For avoiding this high one-sided pressure use is made of the thickness of the rim formed at the peripheral edge of the rotor by the curved shape of the cell bottoms at this point. According to the invention an annular conduit is provided in this rim portion between the pump casing and the rotor. By this conduit all differences in radial hydraulic pressure on the rotor are settled, as in that con.

invention suggests duit only one pressure of average height can exist.

In order that the invention may be clearly understood some embodiments thereof are described in the specification with reference to the annexed drawing.

In the drawing:

Fig. 1 is an end elevational inner View of a rotary pump of the kind referred to, showing in v the left half the rotor in side view and in the right half the interior of the pump casing, the rotor being removed.

Fig. 2 is a vertical axial sectional elevation of the pump shown in Fig. 1 and taken on the line 2--2 of Fig. 1.

Figs. 3, 4, .5, 6 and 7 are axial transverse sections of rotorsv of different forms, shown in the manner as the rotor is shown in Fig. 2, and also showing in the same axial transverse sections the parts of the pump casings enclosing the said rotors.

Fig. 8 is an end elevational inner view of a pump with the rotor removed, showing a casing of a pump of the `kind referred to but having a multiple action, viz. having a plurality of guide passages.

Figs. 9 and 10 are parts of Iside elevations of rotors for pumps according to the invention, havings varies deviating from flat radial planes and having a bent form.

Fig. 1l is an axial transverse section of a rotor having special guiding coresopposite the guide passages in the casing, showing also in the same axial transverse section the parts of the pump casing enclosing the said rotor. 1 90 Fig. 12 is a sidel elevationv of the rotor shown in Fig. 11.`

The pump as shown in Figs. 1 and 2 has a base plate l and comprises a casing 2 formed with members 3 and 4 which are held together by suitable bolts. The casing 2 has laterally extending tubular bosses 5, 6 to receive the shaft 7. These bosses 5, 6 receive suitable packing material thus forming stufng boxes closedby the glands 8, 9 which surround the shaft 7 and are fastened for tightening the packing by suitable bolts.

The apertures formed in the sides of the casing 2 and designed to receive the shaft '7 which may be rotatable therein by any desired -power meansI such as a motor (not shown) are lined by bearing sleeves 10, 11. Of course there maybe other bearing members suchas rolling bearing members (ball bearings, roller bearings etc.) substituted for the bearing sleeves 1G, 1i.' Securedto the shaft 7 in any suitable manner e. g. by a key 12 for rotation therewith is a rotor 13 which will be more fully described in the specification hereafter.

The casing 2 encloses the rotor 13 with a substantially liquid-tight running t as appears clearly from Fig. 2.

The pump shown in Figs. 1 and 2 is a double acting pump viz. both sides of the rotor are used for pumping. It will be understood that pumps as shown in Figs. 1 and. 2 easily can be modified in such a manner that they are single acting, viz. that only one side of the rotor is used for pumping. This will be clear also from the following description of constructional forms of pumps according to the invention.

In the pump shown in Figs. 1 and 2 the supply opening is indicated by 14 and this opening is connected to a suitable source of liquid. The discharge opening 15 is connected to a service line orother desirable line. The openings 14 and 15 lead to a special supply and discharge casing 16 which partly surrounds the sides of the pump casing 2. The said casing 16 is divided by an axial partition 29 into two parts one of which corresponds with the supply opening 14 while the other corresponds with the discharge opening 15. Each of the two parts of the casing 16 is connected with the interior of the pump casing 2. The supply part of the casing 16 is connected at both sides of the rotor 13 with the interior of the pump casing 2 by means of two inlet openings 17. The part of the casing 16 which is connected with the discharge opening 15 is connected With the interior of the pump casing 2 at both sides of the rotor by means of two outlet openings 18. It will be understood that by single acting pumps the casing 16 only extends at one side of the pump casing 2, viz. at the side where the rotor is used for pumping. Then only one inlet opening 17 and one outlet opening 18 need be provided. This also can be applied, however, to doubleacting pumpsif onlythe cells at both sides of the rotor communicate with each other, e. g. as shown already in the rotor of Fig. 2.

The interior of the casing 2 is provided with a guide passage 19 at each rotor side 'used for pump# in g. Thus in the construction according to Figs. 1 and 2 a guide passage of this kind is arranged at each side of the rotor so that the pump casing 2 comprises two guide passages 19 and 20. These guide passages are annular (though interrupted) in shape extending along a greater part of the side faces of the rotor cells but each having two dead ends 21, 22. At these dead ends the bottom of the guide passages is gradually sloped so that it merges into the interior side face of the casing 2. A.

The rotor 13 of thepump in the ordinary manner is provided with vanes forming cells between them, said cells having a height calculated in a radial direction of such size that they rach in the direction of the axis of the pump the inlet and outlet openings 17 and 18 as clearly shown in Fig. 1.

Pumps of the kind described act with an auxiliary liquid circulating in the pump and used always anew. The said auxiliary liquid rotates with the impeller or rotor and each cell of the said rotor is partly filled with it. If this cell reaches the dead end 22 of the guide passage 19 (the rotor rotating in the direction of the arrow 23 in Fig. 1) the auxiliary liquid in the cell will gradually retire from the cell as it enters the guide passage 19. This entering of the guide passage 19 is gradual, due to the sloped bottom of the guide passage at the end 22. As the auxiliary liquid retires from the cell it acts therein like a piston as the inner surface of it' walks outwardly. Hereby the pumping liquid, gas or mixture, is sucked through the opening 17 and thereafter transported by the cell of the rotor. If the cell reaches the dead end 21 of the guide passage 19 the auxiliary liquid is caused to reenter the cell and thereby this auxiliary liquid which has been partly retained in the cell again acts as a piston and now forces the pumping liquid, gas or mixture to enter the outlet opening 18 and thus into the service line.

' It will be understood that the movement of the liquid especially of the auxiliary liquid within the pump is`very complicated. In the rst place it is known that there exist whirlings as indicated in Fig. 2 by the arrows 24 and 25. The invention now has the object to make the interior of the pump formed in such a manner that the liquid flowing therethrough is guided in a possibly unobstructed manner. As shown in Fig. 2 the walls of the cells formed between the vanes in the body of the rotor 13 are curved in the part lying opposite the guide passages 19 and 20, near. the periphery of the rotor and merge gradually into the side walls of the said guide passages. It has appeared that by this measure a considerable increase of lift of the pump can be obtained.

In the Figures 3 to 12 the same reference numbers as in the Figures 1 and 2 are used for indicating corresponding parts as far as possible.

In Fig. 3 an axial transverse section of a rotor of a single acting pump is shown. In this figure also the parts of the pump casing enclosing the said rotor are shown inA the same axial transverse section. It is clearly shown that the cell wall 27 of the rotor opposite the guide passage 28 and near. the periphery of the rotor is curved and merges gradually into the side Wall of the guide passage at the side farthest removed Ifrom the axis of the pump. A

By the increased lift of the p ump the pressur of theliquid in the interior of the pump casing is very much greater in the neighbourhood of the outlet opening 18 than near the inlet opening 1,'7. 'I'hus the shaft 7 can come under the influence of a great'tradial) transverse force which generates varying stresses in the material of the said shaft which are very dangerous. As shown in Fig. 2 there is made use now of the thickness of the rim formed at the peripheral edge of the rotor by the curved shape of the cell bottoms at the periphery of the rotor, by the provision of a circumferential conduit 30 of substantial crosssectional area between the casing and the ,ieripheral edge of the rotor. This conduit extends annularly and circumferentially around the whole of the rotor. Differences in pressure of the liquid within this conduit at different points of the periphery of the rotor cannot exist as they would be settled immediately due to the great `sectional area of the conduit. In this manner the rotor is subjected to the same radial hydraulic pressure in all directions so'that there cannot occur a one-sided force on the shaft 'I any longer. l

In Fig. 3 also the circumferential conduit 30 of Fig. 2 is shown clearly.

Fig. 4 shows in the same manner as Fig. 3 a

pump rotor, however, for a double acting pump as shown in Fig. 2.

The rotor 31 has cells at both sides'of it, the said cells being divided by a common partition 32- which if necessary may be provided with apertures' 33 in order to avoid differences in pressure at both sides of the rotor. The 'bottoms of the cells formed by the said 1partition wall '32 are throughout the height of the cells formed as -a in Figure-4. Furthermore it will be clear that also 'this shape of cell bottom can be applied to single acting rotors asshown in Fig.' 3. p I

Fig. -also shows a double acting pump rotor according to the invention. The partition wall between the cells at both sides of therotor is not continued till the hub 36 of the rotor, so that the cells atboth sides of the rotorA fully communicate with each other. The `bottoms of the cells near the periphery of the rotor are also curved and merge gradually into the side walls of the guide passages. The pressure-settling conduit 30 also can be providedin this constructional form. Y

Fig. 6 shows a doubleacting rotor of the same kind as that of Fig. 15,. only with the difference that a partition wall 37 is continued to the hub 38 and is formed therewith in one piece. 1f necessary apertures 39 may be made inthe partition 3'7- to make the cells at both sides of the rotor, communicate with -each other.

Fig. 7 showsa double acting pump rotor with Vfully communicating cells on both sides of the rotor, the partition wall between them not being formed in one piece with thehub 40, thus in the same manner as in the constructional form according toFig. 5. The partition wall. 41 has opposite that'wall of the guide passages which is nearest to theaxis of the pump, while ythe part of the bottom opposite the guide' passage is curved regularly and merges at the periphery of the rotor gradually into the wall of the guide passage at the side farthest removed from the axis of the pump. It will be understood that in such rotors 'the whirlings indicated by the arrows j 43 are supported highly. It should be taken in mind, however, that sufficient space has to be left between the edges 42 and the inner walls of the casing in order that the auxiliary liquid can freely pass therethrough.

The constructional forms'shown in Figs. 5, 6

.and 7 also can be used for vsingle acting. rotors as shown in Fig. 3. In that event the constructional form of Figs. 5 and 6 will be the same and the partitionwall 4l of Fig. '7 will be connected with the hub of the rotor as all partition walls then will be full -side walls of therotor.A The opening 39 in Fig. 6 of course would be omitted. The circumferential conduits 30 could be arranged, however, as in double acting rotors.

Fig. 8 shows a pump according to the invention in the manner of the right half of Fig. 1 but a pump of multiple action, viz., being subdivided into several working areas. The example given is a quadruple acting pump.' Y

In this pumpthe auxiliary liquid contained in the cellsoffthe rotor enters'guide passagesin the pump casing and reenters the cells again four times per revolution. Theguide passages therefore are divided into a plurality, viz., in -four single guide passages of limited vlength which are indicated in Fig. 8 with the reference numbers 45, 46, 47 and 48.- Each of the said single guide passages corresponds with one inlet .and

one .outlet opening which are indicated in th I drawing (Fig. 8) with the reference numbers 50, 'I

51; 52,53, l54,55, 56, 57 respectively; Thus during a quarter of a revolution of the rotor' each of thefour sector parts of t-he auxiliary liquid lso pulsates'vonce and thus the pump can be cornpared with a piston pump in -which four pistons act simultaneously.

The -four parts canbe interconnected by their inlet and outlet openings in several' manners.`

In Fig. 8 -it is shown how all inlet openings 50, 52,` 54, 5'6 communicate with a commonannular channel 59, which in its yturn communicates with V the supply opening 14. All outlet openings 51,

53; 55,57 communicate with-another common annular channel 60, which in its turn communicates with the discharge opening 15.v Thus the four parts of -the pump work in parallel by which an increase of delivered quant-ity of fluid to be -pumped can be obtained. By a pluralityof arrows the movement of the auxiliary liquidwithin the pump is indicated, while the arrow. 23 indicates the direction of rotation of the rotor. It is also possible to make the four parts of the pump work in series in orderto increase the lift of the pump. Then e. g. the outlet opening 51 has to be connected with the inlet opening 52, the outlet opening 53 with theinlet opening 54, the outlet opening 55 with the inlet opening 56 and at last the outlet opening 57 with the I discharge opening 15.

Of` course the diierent inand outlet openings in'the pump casing can;be interconnected otherwise when connecting the several parts of the pump in series, e. g. in such a manner that the outlet opening 51 is connected with the inlet opening 54 and the o utlet opening l55 with the been provided, however,A with raised edges 42l It will be understood that Ieach of the guide passagesv45, 46, 47and 48 has two dead-ends, the bottoms of whichl are sloped and gradually merge into the surface of 'the inner side wall of the" pump casing; All rotors shown in the Figures 2 to 7 includedand also the rotors shown in the Figures 9 to 12 included which will be described herein'after can be used in pumps according to Fig, 8.

`Fig. 9 shows a part of a side elevation of a rotor according to the invention in which'the varies deviate from a flat radial plane and have a. bent form. It corresponds with forms .of vanes as used also in ordinary centrifugal pumps,

Fig. 10 also showsa bent vane of a rotor according to the invention, said rotor also having -a bent form, however., a helically bent form vas passages for supporting the whirlings indicated by the arrows 63 and 64. The `said cores '61. and

screws 65 (see Fig. 12) or. the like, but also can be cast inone piece with the rotor. Betweenithe dead ends of the guide passages gutters 66 and 67 must be made in the inner side wallof the pump casing in order to take up and to guide4 in a liquid-tight manner the parts of the cores' 62 and 61 which project beyond .the side faces of the rotor.

The particular forms of apparatus shown' and described are of course presented for purposes of explanation and illustration. Various modica- 62 are xed to the body of the rotor e. g. by-

tions can be made without departing from the invention also as defined in the appended claims.

What I claim isz- 1. Rotary pump comprising a rotor having Vanes forming an annular rowv of cells between the vanes in the body of the rotor and a casing enclosing the said rotor with a substantially liquid-tight running flt and having an open guide passage arranged laterally of the rotor, said guide passage extending opposite the row of cells in the rotor for the greater part of the circumferential length of the said row but having two dead ends, inlet and outlet openings being provided laterally of the' rotor in the casing radially inwardly of said guide passages and lying within the reach of the area of the cell openings in the side face of the rotor, the height of the said cells calculated in a radial direction being greater than the width of the guide passage in the casing also calculated in a radial section, the cell walls opposite the guide passage and near the periphery of the rotor being curved and merging gradually into the wall of the guide passage at' the side farthest removed from the axis of the pump, while an annular core fixed to the body of the rotor is arranged in front of the row of cell openings in the side face of the rotor and extends opposite the guide passage between the side walls thereof, a separate annular conduit being formed lbetween the pump casing and the peripheral edge of the rotor by means of an annular open pas- `sage in' the rim formed by the circumferential walls of the cells of the rotor.

2. Rotary pump comprising a rotor having vanes forming an annular row of cells between the vanes in the body of the rotor and a casing enclosing the said rotor with a substantially liquid-tight running fit and having an open guide passage arranged at each side and laterally of the rotor, said guide passages extending opposite the row of cells in the rotor for the greater part of the circumferential length of the said row, but each having two dead ends', inlet and outletopenings being provided laterally of the rotor in the casing radially inwardly of said guide passages and lying within the reach of the area. of the cell openings in the side faces of the rotor, the height of the said cells calculated in a radial direction being greater than the width of the guide passages in the casing also calculated in a radial section, the cell walls opposite the guide passages and near the periphery of the rotor being curved and merging gradually, into the walls of the guide passages at the -side farthest removed from the 'axis of the pump, while annular cores fixed to the body of the rotor are arranged in front of the rows of cell openings in the side faces of the rotor and extend opposite the guide passages belonging thereto between the side walls thereof, a

separate annular conduit being formed between uid-tight running t and having a plurality of i open guide passages arranged laterally of the rotor, said guide passages extending opposite the row of cells in the rotor and each having two dead ends, inlet and outlet openings being provided laterally of the rotor in the casing radially inwardly of said guide passages and lying within the reach of the area of the cell openings in the rotor, the height of the said cells calculated in a radial direction being greater than the width of the guide passages in the casing also calculated in a radial section, the cell walls opposite the guide passages and near the periphery of the rotor being curved and merging gradually into the walls of the guide passages at the side farthest removed from the axis of the pump, while annular cores fixed to the body of the rotor are arranged in front of each row of cell openings in the side faces of the rotor and extend opposite the guide passages belonging thereto between the side walls thereof, a separate annular conduit being formed between the pump casing and the peripheral edge of the rotor by means of an annularv open passage in the rim formed by the circumferential walls of the cells of the rotor.

4. Rotary pump comprising a. rotor having vanes forming an annular row of cells at the periphery of the rotor between the vanes and a casing enclosing the said rotor with a substanlY tially liquid tight running fit and having open guide passages arranged laterally of the rotor, said guide passages extending opposite the vanes of the rotor and having each two dead ends, inlet and outlet openings being provided laterally of the rotor in the casing radially inwardly of said lill guide passages and lying within the reach of the area occupied by the vanes on the side face of the rotor, the height of the said vanes calculated in a radial direction being greater than the width of the guide passages in the casing also calculated in a radial section, the part of the cell walls and bottoms opposite the guide passages and near the periphery of the rotor being curved to merge gradually into the wall of the guide passages at the side farthest removed from the axis of the pump, while an annular core is fixed to the body` of the rotor in front of the row of cell openings in a side face of the rotor and opposite a corre'- sponding guide passage to form a center of rotation for the helical whirl in the liquid at that place.

WILLEM LODEWIJK JOOST SPOOR.

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