Ceramic pump and casting therefor

Abstract

Casing for a volumetric pump, said casing comprising a wall being in ceramic, characterized in that said wall comprises at least one opening means comprising a recess, a through-hole in the bottom of said recess and a nozzle being manufactured inside said recess, said nozzle being concentric with said through-hole and having a length inferior to the depth of the recess.

Claims

1. Casing for a volumetric pump, said casing comprising a wall being in ceramic defining a cylindrical volumetric chamber inside said casing, wherein said wall comprises: at least one opening means comprising a recess, a through-hole through the ceramic wall to connect the volumetric chamber to the outside of said casing in the bottom of said recess and a nozzle inside said recess, said nozzle protruding from the bottom of said recess toward an outside of the casing, said nozzle being concentric around said through-hole and having a length inferior to the depth of the recess.

2. Casing according to claim 1, wherein the at least one opening means comprises two opening means.

3. Casing according to claim 1, wherein said casing is machined from one piece of solid ceramic.

4. Casing according to claim 1, wherein said nozzle is threaded.

5. Casing according to claim 4, wherein said nozzle comprises a truncated cone shaped end.

6. Casing according to claim 5, wherein said nozzle is connected to a polymer duct with the help of polymer ferrule.

7. Casing according to claim 6, wherein said polymer duct is a Teflon duct.

8. Casing according to claim 1, wherein a bore defined by the nozzle and the through-hole is able to accommodate a gasket.

9. Casing according to claim 8, wherein the bore defined by the nozzle and the through-hole comprises at least one annular projection.

10. Casing according to claim 8, wherein the bore defined by the nozzle and the through-hole comprises at least one internal portion and one external portion, said external portion having a larger cross section than the internal portion.

11. Casing according to claim 8, wherein said nozzle comprises an end with two protrusions.

12. Casing according to claim 11, wherein said nozzle is connected to a polymer adapter fastened to said nozzle with the help of a polymer ferrule.

13. Casing according to claim 12, wherein said polymer adapter and polymer ferrule are made of polyether ether ketone.

14. Pump comprising a casing according to claim 1 and a rotating piston able to slide in said casing, said rotating piston comprising a groove and being able to open or close an inlet and outlet of the pump, depending on its angle of rotation.

15. Pump comprising a casing according to claim 1, a piston and a rotary valve, said rotary valve being able to open or close an inlet and outlet of the pump, depending on its angle of rotation.

Description

SHORT DESCRIPTION OF THE DRAWINGS

(1) These and further aspects of the invention will be explained in greater detail by way of example and with reference to the accompanying drawings in which:

(2) FIG. 1 shows a sectional view of a first embodiment of the pump casing according to invention;

(3) FIG. 2 shows an opening of a pump casing according to a second embodiment of the invention;

(4) FIG. 3 shows an opening of a pump casing according to a third embodiment of the invention;

(5) FIG. 4 shows a pump casing according to a fourth embodiment of the invention;

(6) FIG. 5 shows a pump casing according to a fifth embodiment of the invention;

(7) FIG. 6 shows a cross-sectional view of the embodiment according to FIG. 5.

(8) The figures are not drawn to scale. Generally, identical components are denoted by the same reference numerals in the figures.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(9) FIG. 1 shows a sectional view of a first embodiment of the pump casing 1 according to invention. The casing 1 comprises a wall 2 in ceramic, with one opening means comprising a recess 3 and a through-hole 4 in the bottom of said recess 3. A threaded nozzle 5 is manufactured inside said recess 3. The nozzle 5 is concentric with said through-hole 4 and has a length inferior to the depth of the recess. Such condition is equivalent to say that the nozzle is not protruding from the casing. In this embodiment, the nozzle 5 is entirely surrounded by the recess wall 3a. As it can be seen in FIG. 1, the bore defined by the nozzle 5 and the through-hole 4 comprises one internal portion 7 and one external portion 8, the external portion 8 having a larger cross section than the internal portion 7. Such configuration indeed allows to accommodate a gasket 10 between the nozzle 5 and an adapter (not represented) connected to duct.

(10) FIG. 2 shows an enlargement of the opening of a pump casing according to a second embodiment of the invention. In this embodiment, the threaded nozzle indeed comprises an unthreaded truncated cone shaped end 6. Such configuration allows the connection of rigid ducts, as for example Teflon FEP ducts, to the opening means of the pump casing. The truncated cone shaped 6 end is indeed adapted to be inserted inside a semi-rigid duct which is then fastened to the threaded nozzle 5 with the help of polymer ferrule. The height h1 of the nozzle 5 and the depth h2 of the recess 3 are represented in this FIG. 2.

(11) FIG. 3 shows an enlargement of the opening of a pump casing according to a third embodiment of the invention. An unthreaded nozzle 5 can indeed be manufactured. The height h1 of the nozzle 5 and the depth h2 of the recess 3 are also represented in this FIG. 3.

(12) FIG. 4 shows a pump casing according to a fourth embodiment of the invention. The represented embodiment comprises two opening means, to connect inlet and outlet ducts to the pump. The threaded nozzles 5 comprise an end with two protrusions 9. Such configuration for the nozzle allows indeed the fitting of a gasket 10 between the nozzle 5 and a PEEK adapter 11 which is fastened to the threaded nozzle 5 with the help of polymer ferrule (not represented). The protrusions are meant to prevent the rotation of the PEEK adapter 11. Such rotation of the PEEK adapter 11 would indeed induce the rotation and shearing of the gasket 10 during the fastening, which could weaken the insulation properties of the gasket 10. In this embodiment, the recess 3 has a circular shape. Other various shapes could have been envisaged (square, triangle, rectangle . . . ). In this embodiment, the nozzle 5 is consequently entirely surrounded by the recess wall 3a.

(13) FIG. 5 and FIG. 6 represent a pump casing according to a fifth embodiment of the invention. In this embodiment, there are two nozzles 5 manufactured in one recess 3. As in the other embodiments, the length of the nozzles 5 is inferior to the depth of the recess 3, such that the nozzles 5 are not protruding from the casing. In this embodiment, the recess 3 has a U-shaped profile with two walls 12 and two open-sections 13 surrounding the nozzles 5.

(14) It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. The invention resides in each and every novel characteristic feature and each and every combination of characteristic features. Reference numerals in the claims do not limit their protective scope. Use of the verb to comprise and its conjugations does not exclude the presence of elements other than those stated. Use of the article a or an preceding an element does not exclude the presence of a plurality of such elements.

(15) The present invention has been described in terms of specific embodiments, which are illustrative of the invention and not to be construed as limiting.