CA1157315A - Method and apparatus for pumping fragile articles - Google Patents

Abstract

METHOD AND APPARATUS FOR PUMPING
FRAGILE ARTICLES

ABSTRACT OF THE DISCLOSURE
A pump for pumping fragile articles including fish and glasses without damage includes a rotary pump having a plain disc impeller disposed in a substantially cylindrical chamber of a housing with an inlet into, or coaxial of, the impeller into the housing and an outlet from the periphery of the chamber, with the rotor arranged to provide a substantially unobstructed passage between the inlet past the rotor to the outlet or the pump. The method includes pumping fragile articles in a fluid medium by means of a disc impeller pump having an unobstructed passageway between the inlet and outlet or the pump.

Description

10 BAC~GRC~UNV 0~ THE INVI~NT0N
1~e presont lnventlon relate~ to fluld pu.mp~ and p~rtalns partlcularly to method and apparatus for pumplng fraglle ertlcle~..
Rotary dl~c pumps have been known tor ~ con~lderable len6th o~ ~lme.
lhe6e pump3, howe~rer, h~ve not galned wlde~pread use becuu~o they have 15 been unable n the pa~t lo compete effectlvely w Ith posltlve dl~placement pump3 &nd bladed Impeller pumps for the pumpln~ of fluids.
The prlor art of whlch appllcant 19 8~ are Indlcate~ that ~uch pumps h~ve been proposed as early as 1913, wlth mnor improvements belng made thruugh the year~ untll the pre~sent tlme. The prlor art 18 exempllfled, ~r 20 example, by th~ follor~{n3 prior art.patents:
U.S. Patent No. 1" OG1,142, Issued ~lay 18, 191S to N. 're~la.
U,S. Patent No. 2, CU7, 834, l~ued July 20, 1937 to Brown et al~

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U. S. ~atent No. 3, 487, 7~;4, Is~ucd January ~ 70 to Ra~ferty et al.
U. S, Yatent No. 3, 644, 051, lssued February 22, 1972 to Sch3plro.
U. S. Patent No. 4, ~25,225, l~sued May 24, 1977 to Dursnt.
~ ther patents o Intere~t Include Elrltl~h S~s)eclflcatlon No. 17~?, 043, dated Aiay 4, 1922 to ~. Tesla, and French Patent Speclflcatlon No. B6~, 706, ts~ued r~ay 31, 1~41 to G lrod In.
These pumps are all based nn the theory that the rlctlon o~ the flul~
on the ~urfaces of the plate~ of the rotor during rotatlon of the rotor develops10 a centrlfu~al orce propelllng the fluld out toward the perlphery of the 21ates.
The~e all, however, malntaln and recognlze the neces .ity for maintaln~ a f~lrly close toler~nce of the spaclng between the dl:c~. ~here h~s long e~lsteda need for sy~tems for conveylng fraglle artlcle~ rapldly and conven~ently wlthout damage thereto. Frulta and vegetable~, for example9 are curreAtly 15 conveyed by mean~ of ~crew-t~pe conveyor~ when lt a~ e~sentlal to convey them wllhout a fluld medlum. Prlor to the present Inventlon, there haR b~en no known technlque ~or conveying such art~cles by means of a pump In a fluld medlum wlthout damage thereto. Currently, some pumps sre u~ed to unload some ~Ish from ~i~hlng ~-e~els Into proce361ng tank~ or the llke at c~nnerles.
20 Such pump~, holHever, are of the vane type and result Ln a con6ldersble amount of damage to the flsh.
Vane type pump~ are also used ln the pumplng of coal, ~lurry and the llke. ~uch pumps, whlle effectlve In movlng the slurry, are sub~ect to hlgh wear and rapld deterloratlon. They are 2190 ~ubject to clogglng.

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It is therefore desirable that a pump be available which is capable of rapidly and effectively conveying fragile articles by means of a fluid medium over a reasonable distance.
According to one aspect of the present invention there is provided a rotary disc liquid pump for pumping liquid medium, said pump comprising in combination: a housing having walls defining a substantially cylindrical rotor chamber; an inlet coaxially of said chamber; an outlet of communicating with and extending outwardly from said housing at a tangent to the hous- -ing walls at the outer diameter of said chamber; and a rotary disc impeller coaxially mounted in said chamber for rotation therein and comprising first and second coaxially disposed discs each disc having a continuous planar face and an outer diameter slightly less than the diameter of the rotor chamber, with the second disc having a central opening therethrough and spaced from said first disc and connected to said first disc for rotat-ion therewith by means providing a substantially unobstructed passageway between said discs from said inlet to said outlet for the passage of fragile articles of predetermined size entrained in said liquid, said discs being mounted for rotation about their axes, positioned for contact with liquid in said chamber, and spaced apart sufficient to permit the passage of liquid from said inlet past said discs to the outlet.
According to another aspect of the present invention there is provided a method of pumping fragile articles of a pre-determined size in a liquid medium comprising the steps of: sel-ecting a fluid pump having a rotary disc impeller mounted within a cylindrical chamber in a housing with an unobstructed passage defined between an inlet and an outlet, said inlet, outlet and passage having a cross-sectional area exceeding said predetermined size, said outlet extending outward at a tangent to the chamber wall at the outer diameter thereof~ said impeller comprising a rotating disc having an outer diameter slightly less than that of said chamber and having a planar smooth continuous face moun-ted for rotation about its axis with the face at a right angle to the axis closely adjacent the wall opposite the inlet and spaced from and facing the wall having the inlet a sufficient distance to provide an unobstructed passage between the inlet and outlet past the rotating disc for the passage of delicate liquid-borne articles, introducing a mixture of said articles and a liquid into the inlet of said pump, while simultaneously therewith rotating the impeller of said pump in said chamber about the axis thereof, and at a rate to establish and maintain a flow of said mixture of articles and liquid through said pump.
The invention will now be described in greater detail with reference to the accompanying drawings, in which:
Figure 1 is a diagram of a typical use of the pump for moving fish or the like.
Figure 2 is a front elevation view of the pump, with portions cut away.
Figure 3 is a sectional view taken on line 3-3 of Figure 2.
Figure 4 is a front elevation view of an alternative form of the pump, with a portion cut away.
Figure 5 is a sectional view taken on line 5-5 of Figure 4.
Turning now to the drawings, particularly to Figure 1, there is illustrated a pump, designated generally by the numeral 10, pumping live fish 12 from a tank 14 in a fluid 16 such as water into a second tank 18. The second tank also contains fluid 16 such as water. The pump is provided with an inlet con-duit 20 of sufficient size to convey the fish and fluid without - 3a damage to the fish into the pump lO, and therethrough and by way of an outlet conduit 22 in the second tank 18.
As best seen in Figures 2 and 3, the pump lO includes a housing 24 having a generally cylindrical chamber 26 in which is mounted a disc rotor. The housing includes an inlet 28 into the chamber 26 and an outlet 30 from the periphery of the cham-ber 26.
As best seen in Figure 3, the pump rotor includes a first plain disc 32 having a plane impelling surface and a sub-stantially conical-shaped streamlining portion 33, comprising vortex reducing means, projecting toward and concentric with the inlet 28 and the axis of the chamber 26. A second plain disc 34 also of plane configuration includes a central opening 36 concen-tric with and substantially the same diameter of the inlet 28.
The second disc 34 is connected to the inner or drive disc 32 by means of a plurality of pins 38 spaced around the axis and close-ly adjacent thereto. These pins are preferably as close to the central axis of the rotor as possible. This spacing is critical in the handling of fragile articles in that the movement of fluid and articles through the chamber is such that the veloclty of the arllcle~ at thls polnt 18 falrly low and wlll tend to bo movlng at abo~t the same veloclty and dlrectlon a~ thc plns such that Impact thcrcwLth Is subfitantiQlly &voided. ThL~ confl~uratlon as ~hown~ for example, In Flgures 2 and 3, pro~rde~ an es~entlally unobstructed pa~age through the S pump houslng Irom the lnlet 2B to the outlet 30. ~he spaclng between thedl~c~ 32 and 34 ~hould eYceed the maltlmum dlme~slon of the artlcles to be pumped Ln order to lnsure adequate spaclng for unobstructed pa6sage o~ an artlcl~ of a predctcrmlned slze.
Prior plaln dl~c pump~ have emphaslzed the necesslty of close spaclng between the discs In the pump. Heretofore, the spaclng of such pumps, typlcally referred to a~ shear force pumpY, has been consldered to be raLrly crltlcal, It has aluay~ been consldered neces~ary In the past to hsve a falrly closo ~paclng between the dlsc~ In order to get the neces~sry she~r force to propeI the fluld through the pumpO It ha3 been recognlzed, however, 1~
Rafterty et al. Patent U. S. 3, 487, 784, Column 5, that the spaclng can be 88 great as 1/4 of sn Inch and ~till obtsln flow of fluld tberethrough. The Rafferty pump, howe~er, 19 a very low presYure pump prlmarlly for the purpo~e of pumplng blood and does nc>t recognize the ~sslbl1lty of pumplfig artlcles In a fluld, or pumplng wlth large ~paclng between the dlscs.
Appllcant has dl6covered that large spaclng betwèen lhe dlsc~ slble ~nd ot from 1/2 an Inch up to at least as much as a oot or more. Appllcant ha~ esse~tlally dlscovered a pump constructlor. snd method capable o~ pumpl~g hlghly fraglle artlcles such a~ llve fl~h and the llke, from one place to another ~uch as from one tank to another, from a flshlng vessel to the proces~lng tan~
snd the llke.

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-- S --~ he rotor of the pump in Flgure 3 19 mounted on a 6ultable drlve ~ha~t 40 ~uch as by mean~ of a nut 42. The drlve shaft 1~ mounted tn a sultable bearlng sùpport bracket 44 by means of 8 bearlng 48 and Include3 suitable qeal means 48 for ~eallng the shat wiLthln the hou6lng. The hou~lng 18 8upported 5 on a ~ultable base member 50 for mountlng ln the usual manner.
The appllcant has tested and demonstrated the safety and fea~lbLllty of the present Inventlon by means of a prototype In whlch goldflsh were reclrculated from a tank through the pump and back to the tan~ for a perlod of approxlmately two hours. Several hundred goldflch were In~Qlved and no notlceable damage 10 or slde eîfects were noted. rhe day followlng the test, a slngle one of the more than 200 goldflsh was found to be dead. Thls fish wa~ Inspected and no brui~es or c~ntu~ions were ound on the flsh.
An alternate embodiment of the Inventlon 16 ~hown In Flgure 4, whereln a pump de61gnated generally by the numeral S2 Includes a houslng 54 ha~lng a 15 ~ub~tantlally cyllndrlcal Inner chamber 56, ln whlch ls mounted a rotor 58 whlch 16 al~o a plaln dlsc impeller haYlng a forwardly directed, ~omewhat conlcal-shaped vortex reduc~ng portlon 59, whlch projects substantlally the wldth Or the Impeller chamber to sn inlet 60 oî the hou~lng. The houslng, whlch iB of a ~ubstantlally cyllndrlcal co~figuratlon, Includes an outlet ~2 ~hich ~015l8 20 tangentlally o~ the rotor houslng. The lmpeller or rotor 58 1~ mour~ted on a drlve shaft 64 such a~ by means of a nut or the llke- 66. ~he shaft 64 iB mounted ln a sultable bearlng 68 mounted In a bearlng ~upport bracket 70. Sultable 6eal mean~ 7Z ~eals the ~haft agalnst leakage from the Impeller chamber.
Thl3 conflguratlon, as shown ln Flgure 4, 1~ capable of pumpln~ fraglle 25 artlcles ~uch aY gla~s tumble~s, such as l~lustrated In Flgure 4" at 74. The 1~57315 pump In ~hls cor~l~uratlon provlde~ a ~ubstantlally unobstructed pa6sage lrom the lnlet past ~e Impeller 58 Into the outlet. ~'lth thls arrangement, the rrsglle artlc~ee, ~uch as tun~blers, are malntalned 8 suflclent dlstsnce ap~rt 80 as not to impact one another and thus flow wlth the ~luld throu~h the Impeller pumpS chamber ron~ the lnlet to the outlet. ~he artlcles are ~uspended by the 1uld and cushloned agslr~t Impact wlth the pump hou~lng~ A~aln, It has been found that falrly large artlcles may be pump~d In a fluld medlum, 6uch as wster, In pump~ oî thl~ characeer. It has beerl found thst a slngle blade lmpeller ol the disc type as Qhown ln Fl;~ures 4 and 5 1~ capable of applylng su~icle~t ~orc~ to-the fluld wlthln the bou~lng to propel lt through the outlet thereof. rhus, a~lynumber o~ fraglle artlcles and Items may be pumped In the pump in accordsce wlth the Inventlon.
For example, any number of ~rult~, ~uch ~:R Qpple8~ orsnges~ lemon~, ¦ grapefrults, melo~ omatoes and the llke, may be pllmped In a pump In ~ 15 &ccordance wlth the ln~rentlon. Ihe necesssry ~tep3 Or the Inventlon lnclude a the ~electlon OI a rotary dlsc Impeller pump havlng a subetan~lally unobstructed pa~ageway between the lnlet and the outlet wlth a ~ufflclent spaclQg botween the plane facl~g of tbe dL~c~ of the lmpeller and the opposlng wall or ln~pcllerdlsc to permlt pae6sge o~ artlcle6 o a predetermlned slze. ~he artlcle~ are then dl~posed In a nultable 1uld medium such as water and coIr~nunlcated wlth L the Inlet oî the pump, wlth the outlet communlcatlng by ~ultable condulte wlth J the plac2 where It Is de~Lred to pump the artlcle~.
l~hu~, It can be ~een that any number o }rsglle artlcle~ can be puraped by the method and apparatu~ o~ the Inventlon.
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1~57315 i I ~'hlle I hava de~crlbed my Inventlon by means of specl~lc embodlmeDt~, -~ lt 16 to be under~tood that numerol~s changes snd mod~lcatlons msy be made . thereln wlthout depart~ng from the ~plrlt and scope of the ln~rention n~ deflned . ln the apper.ded clalms.
Havlng deecribed my irvenllor~, I now clalm:

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Claims (9)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A rotary disc liquid pump for pumping liquid medium, said pump com-prising in combination: a housing having walls defining a substantially cylin-drical rotor chamber; an inlet coaxially of said chamber; an outlet communicating with and extending outwardly from said housing at a tangent to the housing walls at the outer diameter of said chamber; and, a rotary disc impeller coaxially mounted in said chamber for rotation therein and comprising first and second coaxially disposed discs each disc having a continuous planar face and an outer diameter slightly less than the diameter of the rotor chamber, with the second disc having a central opening therethrough and spaced from said first disc and connected to said first disc for rotation therewith by means providing a sub-stantially unobstructed passageway between said discs from said inlet to said outlet for the passage of fragile articles of a predetermined size entrained in said liquid, said discs being mounted for rotation about their axes, positioned for contact with liquid in said chamber, and spaced apart sufficient to permit the passage of liquid from said inlet past said discs to the outlet.

2. The pump of claim 1, wherein the first and second discs are spaced apart at least 1/2 inch.

3. The pump of claim 2, wherein said second disc is connected to said first disc by means of a plurality of connecting rods spaced annularly around the axis of the discs at the innermost diameter of the outer disc.

4. The pump of claim 1, including vortex reducing means on said first disc.

5. The pump of claim 4, wherein said vortex reducing means comprises a substantially conical projection extending axially of said first disc toward said inlet.

6. The pump of claim 5, wherein said conical projection extends sub-stantially to said inlet.

7. A method of pumping fragile articles of a predetermined size in a liquid medium comprising the steps of: selecting a fluid pump having a rotary disc impeller mounted within a cylindrical chamber in a housing with an unob-structed passage defined between an inlet and an outlet, said inlet, outlet and passage having a cross-sectional area exceeding said predetermined size, said outlet extending outward at a tangent to the chamber wall at the outer diameter thereof, said impeller comprising a rotating disc having an outer diameter slightly less than that of said chamber and having a planar smooth continuous face mounted for rotation about its axis with the face at a right angle to the axis closely adjacent the wall opposite the inlet and spaced from and facing the wall having the inlet a sufficient distance to provide an unobstructed passage between the inlet and outlet past the rotating disc for the passage of delicate liquid-borne articles, introducing a mixture of said articles and a liquid into the inlet of said pump, while simultaneously therewith rotating the impeller of said pump in said chamber about the axis thereof, and at a rate to establish and maintain a flow of said mixture of articles and liquid through said pump.

8. The method of Claim 7, wherein said articles are live fish.

9. The method of Claim 8, wherein said articles are glass tumblers.