Devices for Electroplating Contact Parts of Reed Switches

The functional features of the suspensions used for applying protective electroplating to reed contact parts are investigated. A typical suspension contains two main elements: a magnetic system (MS) and a holder. The requirements for the main structural elements of suspensions that ensure high-quality coatings are formulated.

It is shown that in order to reduce the transient resistance of the reed contact parts, it is necessary to provide a force of pressing them against the base of the holder exceeding 0,07 N. Technical solutions are proposed to achieve the required characteristics of the suspensions:

- modules consisting of strips of magnets 20 mm wide with alternating magnetization; the thickness of the magnetic core in MS does not exceed 2,0 mm, and the distance between the module and the contact parts is 2,0 mm;

• the central part of the base of the suspension holder is 1,0 mm thick, with the thickness of the remaining peripheral part of the base equal to 2,0…4,0 mm;
• guides with a width of 10,0 mm and a thickness of 1,0 mm are fixed on the sides of the surface of the base of the holder facing the MS;
• on the surface of the central part of the holder base there is a permalloy foil with a thickness of 50…100 microns;
• round holes are made in the base of the holder with a thickness of 2,0 mm, in which cylindrical pins made of permalloy are placed.

The use of the developed suspensions provides a 4-5-fold increase in their service life and a ~40% reduction in the total defective reed switches.

1. Rabkin, L. I., Evgenova, I. N. (1976). Magnetically controlled sealed contacts. – Moscow: Nauka. (in Russ.)

2. Karabanov, S. M., Lokshtanova, O. G. (2011). Electrolytic coatings of magnetically controlled sealed contacts (reed switches). – Ryazan: GUL RO Ryazanskaya oblastnaya tipografiya. (in Russ.)

3. Patent US 3386156, H05 K13/02. Method of magnetically loading a mass of articles into a workholder / H. A. Griesemer, D. M. Large. № 516854, filed 28.12.1965, publication date 04.06.1968.

4. Mereckii, A. M. (2011). Fundamentals of electrochemical thermodynamics. Moscow: RHTU im. D.I. Mendeleeva. (in Russ.)

5. Holm, R. (1961). Electrical contacts. Moscow: Izdatelstvo Inostrannoi literature. (in Russ.)

6. Usolcev, A. A. (2009). General electrical engineering. Sankt Peterburg: SPbGU ITMO. (in Russ.)

7. Patent RU № 2747475, МПК G01N 27/72. Device for measuring the power characteristics of permanent magnets / Gorbunov, S. V., Kryutchenko, O. N., Kudinov, V. V., Orlov, A. V. № 2020121213, filed 19.06.2020, publication date 05.05.2021. Byul. № 13. (in Russ.)

8. Patent RU № 2689836, МПК С 25 D 17/06. Magnetic suspension system for electrochemical machining of ferromagnetic parts / Kudinov, V. V., Kryutchenko, O. N., Milyukov, S. M., Orlov, A. V. № 2018125060, filed 09.07.2018, publication date 29.05.2019. Byul. № 16. (in Russ.)

9. Patent RU № 2726054, МПК С 25 D 17/08. Magnetic suspension system for galvanic treatment of ferromagnetic parts / Gorbunov, S. V., Kryutchenko, O. N., Kudinov, V. V., Orlov, A. V. № 2019140619, filed 10.12.2019, publication date 08.07.2020 г. Byul. № 19. (in Russ.)

10. Patent RU № 2702514, МКП С 25Д 17/20. Suspension for galvanic treatment of reed switch contact parts / Karpov, A. S., Kudinov, V. V., Kryutchenko, O. N., Milyukov, S. M., Orlov, A. V. № 2018142024, filed 29.11.2018, publication date 08.10.2018 г. Byul. № 28. (in Russ.)

11. Mashkov, Yu. K. (2013). Tribophysics of metals and polymers. Omsk: OTSU Publishing House. (in Russ.)

12. Patent RU № 2714359, МКП С 25Д 17/20. Suspension for electrochemical processing of reed switch contact parts / Kryutchenko, O. N., Kudinov, V. V., Orlov, A. V., Rashodchikov, D. D. № 2019117583, filed 06.06.2019, publication date 14.02.2020 г. Byul. № 5. (in Russ.)

13. Patent RU № 2805529, МКП С 25Д 17/20. Device for applying galvanic coatings to contact parts of reed switches / Gorbunov, S. V., Gurin, V. A., Kudinov, V. V., Kryutchenko, O. N., Orlov, A. V. № 2 023104435, filed 27.02.2023, publication date 18.10.2023. Byul. № 29. (in Russ.)

14. Patent RU № 2757619, МПК С 25Д 17/20. Suspension for galvanic coating of ferromagnetic parts / Gorbunov, S. V., Kudinov, V. V., Kryutchenko, O. N., Orlov, A. V. № 2021102662, filed 04.02.2021, publication date 27.10.2021. Byul. № 29. (in Russ.)

15. Patent RU № 2668240, МКП С 25D 17/06. Suspension for applying galvanic coatings to contact parts of reed switches / Kryutchenko, O. N., Milyukov, S. M., Orlov, A. V. № 2017146594, filed 28.12.2017, publication date 27.09.2018 г. Byul. № 27. (in Russ.)