Electrolytic pump

• US 5,252,192 A
• Filed: 10/19/1992
• Issued: 10/12/1993
• Est. Priority Date: 10/19/1992
• Status: Expired due to Fees

• Current Assignee: Technic, Inc.
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Ludwig, Frank A.
• Primary Examiner(s): Gluck, Richard E.
• Application Number:
  US07/963,185
• Time in Patent Office: 358 Days
• Field of Search: 417/48, 417/54, 417/55, 417/108, 204/234, 204/237, 204/261, 204/273, 204/278, 204/228, 204/400, 204/434, 204/153.1
• US Class Current: 205/794
• CPC Class Codes: F04B 17/00 Pumps characterised by combination with, or adaptation to, specific driving engines or motors
• CPC Class Codes: G01N 27/28 Electrolytic cell components

Abstract

An apparatus and method for producing an adjustable constant flow of electrochemical fluid. The apparatus is designed for use in an in-tank electrochemical plating bath sensor. The apparatus and method utilize pumping electrodes placed within an electrode chamber. An electrical potential is applied to the electrodes to produce a gaseous stream which produces vertical movement of the electrochemical fluid through the electrode chamber. The voltage applied to the electrodes is periodically reversed in order to prevent the buildup of metal deposits.

Claims

1. An electrolyte pump apparatus adapted for use with an in-tank electrochemical sensor wherein said sensor includes at least one sensing electrode, said electrolytic pump apparatus comprising:

an electrode chamber having a top end and a bottom end through which electrochemical fluid is passed from said bottom end to said top end;

at least two pumping electrodes located within said electrode chamber and above said sensing electrode; and

control means for applying sufficient voltage to said pumping electrodes such that at least one of said electrodes is positively charged relative to the electrochemical fluid while at least one of the other electrodes is negatively charged relative to the electrochemical fluid, wherein said charged pumping electrodes electrolyze the electrochemical fluid within said electrode chamber to produce a gaseous stream within said electrode chamber, said gaseous stream flowing toward said electrode chamber top end to thereby provide for movement of fluid through said electrode chamber while preventing said gaseous stream from interfering with the sensing electrode measurements.

2. The apparatus of claim 1 further including an outlet tube connected to the top end of said electrode chamber through which fluid moves as a result of said gaseous stream.

3. The apparatus of claim 1 wherein said control means further include switching means for selectively applying voltages to said pumping electrodes such that the polarity of each of the electrodes periodically alternates between positive and negative thereby preventing the accumulation of deposits from the electrochemical fluid on the electrodes.

4. The apparatus of claim 1 wherein said control means further includes current control means for varying the current applied to said pumping electrodes to provide control of the amount of gas generated to form said gaseous stream to thereby control the velocity of electrochemical fluid flow through said electrode chamber.

5. The apparatus of claim 1 wherein said electrode chamber is in the shape of a cylinder having a diameter of between about 0.5 and 2.0 centimeters.

6. The apparatus of claim 1 wherein the pumping electrodes are cylindrical in shape.

7. The apparatus of claim 1 wherein the pumping electrodes are located from about 0.5 to 2.0 centimeters apart.

8. The apparatus of claim 1 wherein said pumping electrodes consist essentially of a conductive material selected from the group consisting of platinum, silver, gold, tantalum, treated graphite, and vitreous carbon.

9. The apparatus of claim 2 wherein said pumping electrodes are located between about 10 and 50 centimeters below the top of the outlet tube.

10. A method for pumping electrochemical fluid, said method comprising:

providing an electrode chamber having a top end and a bottom end through which electrochemical fluid is passed from said bottom end to said top end;

providing at least two pumping electrodes located within said electrode chamber and within an in-tank electrochemical sensor, said in-tank electrochemical sensor including at least one sensing electrode wherein said pumping electrodes are located above said sensing electrode; and

applying a sufficient voltage to said pumping electrodes such that at least one of said electrodes is positively charged relative to the electrochemical fluid while at least one of the other electrodes is negatively charged relative to the electrochemical fluid, wherein said voltage applied to said pumping electrodes is sufficient to electrolyze the electrochemical fluid within said electrode chamber to produce a gaseous stream within said electrode chamber, said gaseous stream flowing toward said electrode chamber top end to thereby provide for movement of fluid through said electrode chamber, while preventing said gaseous stream from interfering with the sensing electrode measurements.

11. The method of claim 10 wherein said electrode chamber is completely submerged in said electrochemical fluid.

12. The method of claim 16 wherein the polarity of each of the pumping electrodes is periodically switched between positive and negative.

15. The method of claim 12 wherein the polarity of each pumping electrode is reversed every one to sixty seconds.

13. The method of claim 16 wherein the velocity of electrochemical fluid flow through said electrode chamber is adjusted by varying the current applied to said pumping electrodes.

14. The method of claim 13 wherein the current applied to the pumping electrodes is between about 0.5 and 4.0 amperes.