DK147605B

DK147605B - PUMP FOR MEASURING AND MIXING FLUIDS

Info

Publication number: DK147605B
Application number: DK481979A
Authority: DK
Inventors: Albert Charles Hersom; Kenneth William Wright
Original assignee: Nestle Sa
Priority date: 1978-12-14
Filing date: 1979-11-14
Publication date: 1984-10-15
Also published as: ES486844A1; DE2962850D1; CA1160101A; DK481979A; DK147605C; EP0012467A1; EP0012467B1

Description

i 147*06in 147 * 06

Opfindelsen vedrører en pumpe til udmåling og blanding af et relativt tykt fluidum eller en opslæmning af faste partikler i en væske med f.eks. en anden væske, hvilken pumpe omfatter en cylinder med 5 en første tilgang, en anden tilgang og en afgang, organer til at lukke forbindelsen mellem cylinderen og den første tilgang og mellem cylinderen og afgangen, og inden i cylinderen to bevægelige stempler.The invention relates to a pump for measuring and mixing a relatively thick fluid or slurry of solid particles in a liquid, e.g. a second liquid, said pump comprising a cylinder having a first approach, a second approach and a discharge, means for closing the connection between the cylinder and the first approach and between the cylinder and the outlet, and within the cylinder two movable pistons.

Fra tysk fremlæggelsesskrift nr. 1 173 805 10 kendes der en blandepumpe, der har et differential-stempel med tre forskellige diametre i tre forskellige kamre. Det fortrængte volumen i det første kammer, hvor væske suges ind, er større end det fortrængte volumen i det andet kammer, hvortil væske 15 føres fra det første kammer. Væsken trykkes derfor ind i det tredie kammer, hvori opslæmning også suges ind, og væsken blandes med denne. I den ene udførelsesform, hvor cylindrene er sammenbyggede, kan det fortrængte volumen ikke ændres. Endvidere anvendes 20 der kugleventiler, hvilket ikke er praktisk ved blandinger, hvor der er partikler i opslæmningen.German Patent Specification No. 1,173,805 10 discloses a mixing pump having a differential piston having three different diameters in three different chambers. The displaced volume in the first chamber into which fluid is sucked is greater than the displaced volume in the second chamber to which fluid 15 is fed from the first chamber. The liquid is therefore pressed into the third chamber in which slurry is also sucked in and the liquid is mixed with it. In one embodiment where the cylinders are assembled, the displaced volume cannot be changed. Furthermore, ball valves are used, which is not practical for mixtures where there are particles in the slurry.

Fra tysk patentskrift nr. 575 142 kendes der en målepumpe, der er forsynet med to stempler, der er indrettet til at bevæges i forhold til hinanden, 25 og hvor der er en ventil i det ene stempel. Denne pumpe er imidlertid ikke en blandepumpe, og formålet med de to stempler er at fjerne luft i cylinderrummet med det udmålte fluidum.German Patent Specification No. 575 142 discloses a measuring pump which is provided with two pistons arranged to move relative to each other, 25 and in which there is a valve in one piston. However, this pump is not a mixing pump and the purpose of the two pistons is to remove air in the cylinder compartment with the measured fluid.

Med pumpen ifølge opfindelsen afhjælpes de 30 nævnte mangler og ulemper ved, at hvert stempel er bevægeligt i forhold til det andet og har mindst én port forsynet med en eller flere ventiler, at de to tilgange findes på hver sin side af stemplerne, at ventilen eller ventilerne i det nærmest afgangen væ-35 rende, første stempel er indrettet til at åbne ved 2 147606 stemplernes trykslag, og at ventilen eller ventilerne i det andet stempel er kontraventiler, der er indrettet til at åbne ved stemplernes sugeslag.With the pump according to the invention, the above-mentioned shortcomings and disadvantages are remedied by the fact that each piston is movable relative to the other and has at least one port provided with one or more valves, that the two approaches are located on either side of the pistons, that the valve or the valves in the near-exit first piston are arranged to open at the pressure stroke of the pistons and that the valve or valves in the second piston are non-return valves arranged to open at the suction stroke of the pistons.

Ved hjælp af det ene stempel indsuges den ene 5 bestanddel, f.eks. en opslæmning, gennem den første tilgang, ved hjælp af det andet stempel indsuges den anden bestanddel, f.eks. en væske, gennem den anden tilgang. Ved en passende tilpasning af de to stemplers relative bevægelser og åbning af ventilerne i 10 stemplerne på passende måde kan der tilvejebringes den ønskede udmåling og blanding.By means of the one plunger, one component is sucked in, e.g. a slurry, through the first approach, is sucked in by means of the second piston, the second component, e.g. a fluid, through the second approach. By appropriately adjusting the relative movements of the two pistons and opening the valves in the pistons appropriately, the desired metering and mixing can be provided.

Ifølge en foretrukket udførelsesform for opfindelsen er forbindelsen mellem cylinderen og enten den første tilgang eller afgangen indrettet til at 15 lukkes ved hjælp af en omstillingsventil. Efter indsugning af de ønskede mængder omstilles ventilen, så at det blandede og udmålte materiale kan afgives gennem afgangen, samtidig med at den første tilgang er lukket, 20 Opfindelsen forklares nærmere i det følgende under henvisning til tegningen, hvor fig. 1 i et skematisk snit viser en udførelsesform for opfindelsen med komponenterne i udgangsstillingen for en pumpeperiode, 25 fig. 2 samme snit som i fig. 1, men med kom ponenterne i en stilling under pumpeperioden, fig. 3 et skematisk snit i en anden udførelsesform for opfindelsen med komponenterne ved begyndelsen af et udmålingsslag, og 30 fig. 4 samme snit som i fig. 3, men med kom ponenterne i nærheden af afslutningen af blande- eller fortyndingsslaget.According to a preferred embodiment of the invention, the connection between the cylinder and either the first inlet or outlet is arranged to be closed by means of a switching valve. After the intake of the desired quantities, the valve is adjusted so that the mixed and metered material can be dispensed through the outlet while the first approach is closed. The invention is explained in more detail below with reference to the drawing, in which fig. 1 is a schematic sectional view showing an embodiment of the invention with the components in the initial position of a pumping period; FIG. 2 shows the same section as in FIG. 1, but with the components in a position during the pumping period; FIG. 3 is a schematic sectional view of another embodiment of the invention with the components at the beginning of a metering stroke; and FIG. 4 shows the same section as in FIG. 3, but with the components near the end of the mixing or dilution stroke.

På tegningen ses pumpen omfattende en cylinder 1, hvori to stempler 2 og 3 kan reciprocere.The drawing shows the pump comprising a cylinder 1, in which two pistons 2 and 3 can reciprocate.

35 Stemplet 2 er monteret på en stempelstang 4, og 147605 3 stemplet 3 er monteret på et rør 5, som er koak-sialt med stempelstangen 4. Stempelstangen 4 og røret 5 aktiveres uafhængigt af hinanden ved hjælp af ikke viste organer (f.eks. pneumatiske cylindre).The piston 2 is mounted on a piston rod 4, and the piston 3 is mounted on a tube 5 coaxial with the piston rod 4. The piston rod 4 and the tube 5 are actuated independently of each other by means not shown (e.g. pneumatic cylinders).

5 I en anden udførelsesform aktiveres og synkroniseres de ved hjælp af knastorganer. Indstillelige stop begrænser stempelslaget.In another embodiment, they are activated and synchronized by means of cam means. Adjustable stops limit the punch stroke.

Stemplet 2 har en midterport, som normalt er holdt lukket af en ventil 6 ved hjælp af spæn-10 dingen i en fjeder, der er koaksial med stempelstangen 4. I en anden udførelsesform er stemplet 2 monteret på stempelstangen 4, og ventilen 6 aktiveres af uafhængige organer.The piston 2 has a central port which is normally closed by a valve 6 by means of the tension of a spring coaxial with the piston rod 4. In another embodiment, the piston 2 is mounted on the piston rod 4 and the valve 6 is actuated by independent bodies.

Stemplet 3 omfatter flere porte med kontra-15 ventiler, der muliggør, at væske kun kan strømme fra højre til venstre på tegningen.The piston 3 comprises several ports with counter valves which allow fluid to flow only from right to left in the drawing.

Cylinderen 1 omfatter to tilgange fortrinsvis under passende tryk, idet den første tilgang 8 er for et tykt fluidum eller en opslæmning, og den 20 anden tilgang 9 er for en væske. Cylinderen har også en afgang 10, hvorigennem den fremkomne blanding eller fortyndet fluidum kan strømme.Cylinder 1 preferably comprises two approaches under appropriate pressure, the first approach 8 being for a thick fluid or slurry and the second approach 9 being for a liquid. The cylinder also has an outlet 10 through which the resulting mixture or diluted fluid can flow.

I en foretrukket udførelsesform åbner en drejelig omstillingsventil 11 en port ved enden af 25 cylinderen (til venstre på tegningen), så at cylinderen kan være forbundet enten med den første tilgang 8 (som vist i fig. 1) eller med afgangen 10 (som vist i fig. 2). Denne omstillingsventil aktiveres synkront med bevægelse af stemplerne 2 og 3 30 ved hjælp af ikke viste organer.In a preferred embodiment, a rotatable switching valve 11 opens a gate at the end of the cylinder (to the left of the drawing) so that the cylinder can be connected either to the first approach 8 (as shown in Figure 1) or to the outlet 10 (as shown in Figure 2). This switching valve is activated synchronously with movement of pistons 2 and 3 by means not shown.

I en anden udførelsesform er den første tilgang 8 forsynet med en kontraventil, der muliggør, at fluidum kan strømme ind i cylinderen, men hindrer det i at strømme ud gennem denne tilgang. Afgan-35 gen 10 er forsynet med en kontraventil, der mulig- 147605 4 gør, at den fremkomne blanding eller det fortyndede fluidum kan strømme ud af cylinderen, men hindrer indsugning. Driften af pumpen foregår som følger:In another embodiment, the first approach 8 is provided with a non-return valve which allows fluid to flow into the cylinder but prevents it from flowing through this approach. The exhaust 10 is provided with a non-return valve which allows the resulting mixture or diluted fluid to flow out of the cylinder but prevents suction. The operation of the pump is as follows:

Begyndende med stillingen i fig. 1 bevæger de 5 to stempler 2 og 3 sig fra venstre mod højre, idet stemplet 3 har en større hastighed og en længere slaglængde end stemplet 2. Under denne bevægelse trækker stemplet 2 fluidum ind gennem den første tilgang 8 (ventilen 6 er lukket), medens 10 den væske, der er suget ind gennem den anden tilgang 9 passerer fra højre til venstre side af stemplet 3 gennem kontraventilerne 7. Ved afslutningen af slaget vil en portion af væske, der er indført gennem den anden tilgang 9, befinde sig mellem stemp-15 lerne 2 og 3, og en del af det fluidum, der er indført gennem den første tilgang 8, er indeholdt mellem omstillingsventilen 11 og stemplet 2.Starting with the position of FIG. 1, the two pistons 2 and 3 move from left to right, the piston 3 having a greater velocity and a longer stroke than the piston 2. During this movement, the piston 2 draws fluid through the first approach 8 (the valve 6 is closed), while the liquid sucked in through the second approach 9 passes from the right to the left side of the piston 3 through the check valves 7. At the end of the stroke, a portion of liquid introduced through the second approach 9 will be between pistons. 15 and 2, and a portion of the fluid introduced through the first approach 8 is contained between the switch valve 11 and the piston 2.

Omstillingsventilen 11 tilvejebringer nu en forbindelse mellem cylinderen 1 og afgangen 10 20 (fig. 2), og stemplerne bevæger sig den anden vej (dvs. fra højre mod venstre på tegningen). Kontraventilerne 7 lukker, og stempelstangen 4 åbner ventilen 6. På denne måde passerer den portion væske, der var indeholdt mellem de to stempler, gennem 25 stemplet 2 og blander sig med fluidumet. Ved afslutningen af slaget tvinges blandingen gennem afgangen 10 i sin helhed, og perioden begynder igen.The switching valve 11 now provides a connection between the cylinder 1 and the outlet 10 20 (Fig. 2) and the pistons move the other way (ie from right to left in the drawing). The check valves 7 close and the piston rod 4 opens the valve 6. In this way, the portion of liquid contained between the two pistons passes through the piston 2 and mixes with the fluid. At the end of the stroke, the mixture is forced through exit 10 in its entirety and the period begins again.

I den i fig. 3 og 4 viste udførelses form kan 12a og 12b anses som to dele af en cylinder 12 30 vinkelret på hinanden. Som i udførelsesformen i fig.In the embodiment shown in FIG. 3 and 4, 12a and 12b can be regarded as two parts of a cylinder 12 perpendicular to each other. As in the embodiment of FIG.

1 og 2 omfatter pumpen to tilgange fortrinsvis under passende tryk, idet den første tilgang 13 er beregnet til et tykt fluidum eller en opslæmning, og den anden tilgang 14 er beregnet til en væske. Denne 35 pumpe omfatter også en afgang 16, gennem hvilken 5 147805 den fremkomne blanding eller det fortyndede fluidum strømmer, og en drejelig omstillingsventil 17, der åbner en port ved enden af delen 12b (til venstre på tegningen) og således tilvejebringer en forbin-5 delse mellem cylinderen og enten tilgangen 13 (som vist i fig. 3) eller afgangen 16 (som vist i fig.1 and 2, the pump preferably comprises two approaches under appropriate pressure, the first approach 13 being for a thick fluid or slurry and the second approach 14 being for a liquid. This pump also includes an outlet 16 through which the resulting mixture or diluted fluid flows, and a rotatable switch valve 17 which opens a port at the end of the portion 12b (to the left of the drawing) and thus provides a connection 5. between the cylinder and either the inlet 13 (as shown in FIG. 3) or the outlet 16 (as shown in FIG.

4). Denne omstillingsventil aktiveres synkront med bevægelserne af stemplet 18, der reciprocerer i delen 12a af cylinderen, og af stemplet 19, der re-10 ciprocerer i delen 12b af cylinderen.4). This switching valve is activated synchronously with the movements of the piston 18 reciprocating in the portion 12a of the cylinder and of the piston 19 reprocessing in the portion 12b of the cylinder.

Stemplet 18 er monteret på en stempelstang 20 og aktiveres ved ikke viste organer, som f.eks. en pneumatisk cylinder, der er forbundet med stempelstangen 20. Stemplet 19 er monteret på en stem-15 pelstang 21 og holdes normalt ved den højre ende af delen 12b af cylinderen ved hjælp af spændingen i en skruefjeder, der er koaksial med stempelstangen 21. Stop begrænser bevægelsen af stemplerne.The piston 18 is mounted on a piston rod 20 and is actuated by means not shown, e.g. a pneumatic cylinder connected to the piston rod 20. The piston 19 is mounted on a piston rod 21 and is usually held at the right end of the part 12b of the cylinder by the tension of a coil spring coaxial with the piston rod 21. Stop restricts the movement of the pistons.

Stemplet 18 har flere porte, der er forsy-20 net med kontraventiler, der kun muliggør, at en væske kan strømme gennem stemplet, når sidstnævnte bevæger sig opefter. Stemplet 19 har en midterport med en ventil 22, der normalt er lukket af en skruefjeder. Denne ventil 22 er forbundet med en 25 plade 23, der er placeret i et kammer inden i stemplet. Kammeret er i forbindelse med delen 12b af cylinderen gennem porte i højre væg af stemplet.The piston 18 has several ports provided with non-return valves which only allow a liquid to flow through the piston as the latter moves upwards. The plunger 19 has a central port with a valve 22 normally closed by a coil spring. This valve 22 is connected to a plate 23 located in a chamber within the piston. The chamber is in connection with the part 12b of the cylinder through gates in the right wall of the piston.

Pumpen virker som følger:The pump works as follows:

Begyndende med stillingen i fig. 3 bevæger 30 stemplet 18 sig opefter, idet dets kontraventiler åbner, og væske, der træder ind gennem tilgangen 14, passerer fra den øvre til den nedre side af stemplet. På grund af trykudligningen mellem stemplerne 18 og 19, medens førstnævnte passerer opef-35 ter, lukker ventilen 22 ved hjælp af en skrue-Starting with the position of FIG. 3, the plunger 18 moves upwardly as its non-return valves open and fluid entering through the inlet 14 passes from the upper to the lower side of the plunger. Due to the pressure equalization between the pistons 18 and 19, while the former passes upwards, the valve 22 closes by means of a screwdriver.

Claims

147005 spring, stain 19 moves from left to right and sucks the thick fluid or slurry into the cylinder through the inlet 13, When the piston 18 has reached its upper position and the piston 19 5 its stop on the right side, the portion 12a of the cylinder will be full of liquid and the portion 12b of the cylinder will be full of the thick fluid or slurry. This is the end of the metering stroke. The switch valve 17 is then turned to the 10 position as shown in FIG. 4 and provides connection between cylinder 12 and outlet 16. Piston 18 moves downwardly, its check valves close, fluid is sucked into the cylinder through inlet 14, and piston 19 moves left 15 with fluid between pistons 18 and 19 until it reaches its left stop. The fluid pressure on the plate 23 then opens the valve 22 (Fig. 4) and fluid passes through the center port of the plunger 19 toward the outlet 16. When the plunger 18 has reached its lower 20 stop, the mixing or dilution stroke is terminated and the period begins again. 1. A pump for measuring and mixing a relatively thick fluid or slurry of solid particles in a liquid, e.g. a second liquid, said pump comprising a cylinder (1; 12) having a first inlet (8? 13), a second inlet (9; 14) and a outlet (10; 16), means (11, 17) for closing the connection between the cylinder (1; 12) and the first approach (8; 30 13) and between the cylinder and the outlet (10; 16), and within the cylinder two movable pistons (2,3; 19,18), k terminated by, each piston being movable relative to the other and having at least one port provided with one or more valves (6, 7; 35 22), the two approaches (8, 9; 13, 14) being provided on each