DEVICE FOR THE ELECTROPOLISHING OF MULTIPLE FREE-MOVING ITEMS BY MEANS OF SOLID ELECTROLYTES

Abstract

An assembly for electropolishing metal surfaces by means of particles of solid electrolytes in a gaseous environment. According to one embodiment the assembly includes a container and a housing element configured to house at least two metal parts, so as to contain the parts avoiding that they can go out during the electropolish process and at the same time allowing that they can have a given movement within the housing element and at the same time endow them with electrical connectivity by means of a first electrode and a second electrode that are coupled to an electrical source 3. The assembly also includes means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts.

Claims

1. An assembly for electropolishing metal surfaces using particles of solid electrolytes, the assembly comprising: a container that holds the particles of solid electrolytes in a gaseous environment; an electrical source; a housing element located inside the container and configured to house at least two metal parts such that the at least two metal parts have a freedom movement inside the housing element, the housing element configured to prevent a falling out of the at least two metal parts during an electropolishing of the at least two metal parts, the housing element including a first electrode for connecting the at least two metal parts to a first pole of the electrical source; a second electrode located inside the container and connected to a second pole of the electrical source, the first and second poles having opposite polarities; and means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts.

2. The assembly according to claim 1, wherein the particles of solid electrolytes partially fill the container.

3. The assembly according to claim 1, wherein the housing element includes at least first and second compartments for respectively holding the at least first and second metal parts.

4. The assembly according to claim 3, wherein each of the at least first and second compartments includes walls that are electrically conductive.

5. The assembly according to claim 3, wherein each of the at least first and second compartments includes walls that are electrically nonconductive.

6. The assembly according to claim 1, wherein the housing element includes a base configured to support the at least first and second parts, the base comprising a plurality of through holes that are sized to permit a passage of the particles of solid electrolytes therethrough.

7. The assembly according to claim 6, wherein the base is a mesh.

8. The assembly according to claim 1, further comprising a vibrator element coupled to the housing and configured to provoke a vibration of the at least first and second metal parts inside the housing element when the vibrator element is energized.

9. The assembly according to claim 6, wherein the particles of solid electrolytes partially fill the container and the container is rotatable by an actuator, the housing element and the second electrode being configured to move integrally with the container such that when the container rotates the particles of solid electrolytes pass through the plurality of holes in the base of the housing element.

10. The assembly according to claim 9, further comprising a third electrode located inside the container, the second electrode and the third electrode being configured to be alternatively connected to the second pole of the electrical source depending on an orientation of the container, the second electrode being located on a first side of the housing element, the third electrode being located on a second side of the housing element, the second side being opposite the first side, the actuator being configured to cause the container to assume a first orientation in which the second electrode is located above the third electrode and a second orientation in which the third electrode is located above the second electrode, the movement of the container between the first and second orientations causing a movement of the particles of solid electrolytes across the at least first and second metal parts and the second and third electrodes.

11. The assembly according to claim 10, further comprising first and second plates that each comprise a plurality of through holes, the first plate being located on the first side of the housing element, the second electrode being located nearer the housing element than the first plate, the second plate being located on the second side of the housing element, the third electrode being located nearer the housing element than the second plate.

12. The assembly according to claim 1, wherein the means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts causes a rotating movement of the housing element within the particles of solid electrolytes.

13. The assembly according to claim 12, wherein the second electrode moves together with the housing element.

14. The assembly according to claim 1, wherein the second electrode is in electrical contact with the particles of solid electrolytes.

15. The assembly according to claim 1, wherein the housing element and the second electrode are submerged in the particles of solid electrolytes, and the means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts includes a recirculation system that takes the particles of solid electrolytes disposed at a bottom of the container and delivers them into a top part of the container at a location above the housing element.

16. The assembly according to claim 15, further comprising a vibrator device coupled to the container that when energized is configured to provoke an improvement in the recirculation of the particles of solid electrolytes.

17. The assembly according to claim 1, wherein the element and the second electrode are submerged in the particles of solid electrolytes, the means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts comprising a piston that moves inside the container alternating towards and away from the housing element to cause a movement of the particles of solid electrolytes in relation to the housing element.

18. The assembly according to claim 17, wherein when the piston moves towards the housing element, the electrical source applies an electric current to the first electrode and to the second electrode, and when the piston moves away from the housing element, the electrical source does not apply an electric current to the first electrode and to the second electrode.

19. The assembly according to claim 1, wherein the housing element and the second electrode are submerged in the particles of solid electrolytes and the means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts includes an actuator that is configured to move the housing element within the particles of solid electrolytes.

20. The assembly according to claim 1, wherein the housing element and the second electrode are submerged in the particles of solid electrolytes and the means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts includes a toroid vibrator or a circular vibrator that provokes a circular movement of the particles of solid electrolytes within the container.

21. The assembly according to claim 1, wherein the housing element and the second electrode are located submerged in the particles of solid electrolytes and are each fixed inside the container, the means to produce a relative movement between the particles of solid electrolytes and the at least two metal parts including one or more actuators that act on the container to cause both a translational movement and a rotational movements of the container.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] To complement the description being carried out and in order to assist to best understanding the characteristics of the invention, attached to this specification, as an integral part thereof, there is a set of drawings in which, for illustration and no limitation purpose, the following has been represented:

[0050] FIG. 1.—It shows a schematic basic view of the invention.

[0051] FIG. 2.—It shows a schematic view of the “hourglass-like” formation.

[0052] FIG. 3.—It shows a schematic view of the “waterwheel-like” formation.

[0053] FIG. 4.—It shows a schematic view of the “recirculation-like” formation.

[0054] FIG. 5.—It shows a schematic view of the “pistons-like” formation.

[0055] FIG. 6.—It shows a top view of a formation of the element 1

[0056] FIG. 7.—It shows a lateral view of the formation of the element 1 of the FIG. 6.

[0057] FIG. 8.—It shows a top view of another formation of the element 1.

PREFERRED EMBODIMENT OF THE INVENTION

[0058] Below, a preferred embodiment is described to polish engraved stainless-steel discs of a 40 mm diameter by 0.5 mm height.

[0059] The device is of the “waterwheel-type” schematized in the FIG. 3. It possesses four elements 1. Each element 1 consists of 128 compartments (8×16), square-shaped, designed to house one disc each. Each compartment has a 45 mm side and a 2 mm height, a base of Titanium MMO mesh in which the wires are spaced 5 mm. The mesh base is connected to the electrical source. Covering all the compartments there is a removable net with a 10 mm gap that avoids that the discs to be polished go out from the compartment during the process. Above the net, at 10 mm of the mesh base, there is another mesh of Titanium MMO, that serves as electrode (4), therefore it is connected to the complementary pole of the electric source.

[0060] Each element 1 is equipped with a vibrator. Each element 1 is joined to the rotation axis, and in turn it possesses an own rotation center. The final movement of the element 1 with respect to the rotation center can be of circular translation, orbital, free, fixed, etc. The rotation axis that joins to the four elements 1 is adjustable as for the height.

[0061] The electric source 3 is a pulse source that allows to control the voltage and length of the positive and negative pulses and the pauses between them. To polish the stainless-steel discs, optimal parameters are +15 V 300 ms; 0 V 10 ms; 15 V 30 ms; 0 V 10 ms.

[0062] The particles of solid electrolyte 5 are spheric particles of gel of poly(styrene-covinylbenzene) with a distribution of sizes centered in 750 μm with a sulfonation corresponding to 1.7 eq/L. The liquid fraction of the gel is a solution of methane sulfonic acid at 5%. The particles of electrolyte are contained in a polypropylene tank, it includes outlets to be able to inject gases and liquids. It possesses four vibrators to fluidify the whole of the particles.