Methods and apparatus for transfer switch

• US 6,849,811 B1
• Filed: 07/31/2000
• Issued: 02/01/2005
• Est. Priority Date: 07/31/2000
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: General Electric Company
• Inventors: Serrano, Mark A., Gamazon, Ariel M., Heflin, Chris
• Primary Examiner(s): LEE, KYUNG S
• Application Number:
  US09/629,244
• Time in Patent Office: 1,646 Days
• Field of Search: 200 1 R- 1 V, 200 2- 18, 307/64, 307112-150
• US Class Current: 200/1.00R
• CPC Class Codes: H01H 1/225 the supporting member being pivotable
• CPC Class Codes: H01H 1/5822 Flexible connections between movable contact and terminal
• CPC Class Codes: H01H 11/041 by bonding of a contact marking face to a contact body portion
• CPC Class Codes: H01H 2300/018 Application transfer; between utility and emergency power supply circuits in H02J9/04
• CPC Class Codes: H01H 51/08 Contacts alternately opened and closed by successive cycles of energisation and de-energisation of the electromagnet, e.g. by use of a ratchet
• CPC Class Codes: H01H 9/0066 Auxiliary contact devices for arc transfer H01H9/38; for electromagnetic relays H01H50/541

Abstract

A transfer switch for switching between power sources for a load includes a plurality of symmetrical phase plates, a plurality of stationary contact pads associated with each said phase plate, each stationary contact pad associated with a power source, a movable contact assembly associated with each phase plate, and a shaft connecting the phase plates and upon which each movable contact assembly is mounted for movement between stationary contact pads associated with each phase plate. The above transfer switch allows for two, three and four-pole modular configuration with minimal additional hardware.

Claims

1. A transfer switch for switching between power sources for a load, said transfer switch comprising:

a plurality of phase plates, each said phase plate comprising a centerline about which said phase plate is configured symmetrically;

a plurality of stationary contact pads associated with each said phase plate, each said stationary contact pad associated with a power source;

a movable contact assembly associated with each said phase plate, wherein said movable contact assembly includes a movable finger attached to a braid assembly; and

a shaft connecting said phase plates and upon which each said movable contact assembly is mounted for movement between said stationary contact pads associated with each said phase plate.

2. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein one of said movable contact pads comprises silver and tungsten.

3. A transfer switch in accordance with claim 2 wherein said braid assembly comprises a single-piece braid and mounting ports configured to prevent rotation of said braid assembly.

4. A transfer switch in accordance with claim 2 further comprising a mechanical drive assembly configured to rotate said movable finger, wherein said mechanical drive assembly further comprises a solenoid assembly, a fork assembly and a mass driver assembly, said solenoid assembly linked to said mass driver assembly, said mass driver assembly movably connected to said fork assembly.

5. A transfer switch in accordance with claim 2 further comprising a mechanical drive assembly configured to rotate said movable finger, wherein said mechanical drive assembly includes a fork assembly, wherein said fork assembly comprises a centerline about which said fork assembly is symmetrical.

6. A transfer switch in accordance with claim 2 further comprising a mechanical drive assembly configured to rotate said movable finger, wherein said mechanical drive assembly includes a mass driver assembly, wherein said mass driver assembly further comprises a manual handle insertion point and positional indicators.

7. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein one of said movable contact pads further comprises forty percent silver and sixty percent tungsten.

8. A transfer switch in accordance with claim 7 wherein said movable contact assembly further comprises a carrier cover, said cover further comprising embedded alignment features.

9. A transfer switch in accordance with claim 7 wherein said movable contact assembly further comprises a carrier, and said carrier comprises an acceptance hole for said shaft.

10. A transfer switch in accordance with claim 7 wherein said movable contact assembly further comprises a carrier, said carrier includes an acceptance hole for said shaft, and said acceptance hole is hexagonal.

11. A transfer switch in accordance with claim 7 wherein said movable contact assembly further comprises a carrier, and said carrier comprises integral baffling.

12. A transfer switch in accordance with claim 7 wherein said movable contact assembly further comprises a carrier cover and a carrier, and said carrier and said cover comprise braid shields.

13. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein one of said movable contact pads comprises a curved surface.

14. A transfer switch in accordance with claim 13 further comprising a plurality of arc chute assemblies, wherein said phase plates are associated with said arc chute assemblies, and one of said arc chute assemblies further comprises two identical arc chute plates reversible for assembly.

15. A transfer switch in accordance with claim 14 wherein said arc chute plates comprise molded thermoset plastic.

16. A transfer switch in accordance with claim 13 further comprising a plurality of arc chute assemblies, wherein said phase plates are associated with said arc chute assemblies, and one of said arc chute assemblies further comprises a plurality of deion plates locked in a plurality of embedded locking locations.

17. A transfer switch in accordance with claim 13 further comprising a plurality of arc chute assemblies, wherein said phase plates are associated with said arc chute assemblies, and one of said arc chute assemblies further comprises a plurality of venting orifices.

18. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein one of said movable contact pads comprises a waffle-patterned brazed surface.

19. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein one of said movable contact pads comprises a surface brazed using a BcuP5 alloy.

20. A transfer switch in accordance with claim 1 wherein one of said stationary contact pads further comprises 50 percent silver, 37.5 percent tungsten, and 12.5 percent tungsten carbide.

21. A transfer switch in accordance with claim 1 wherein one of said stationary contact pads comprises a surface brazed using a BcuP5 alloy.

22. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein said movable finger configured to bring one of said movable contact pads into contact with one of said stationary contact pads using a sweeping action.

23. A transfer switch in accordance with claim 1 further comprising movable contact pads mounted on said movable finger, wherein said movable finger configured to remove one of said movable contact pads from contact with one of said stationary contact pads using a sweeping action.

24. A transfer switch in accordance with claim 1 wherein said stationary contact pads are associated with phase currents and a neutral current, and wherein each of said stationary contact pads further comprises a first thickness, said first thickness associated with the neutral current greater than second thickness associated with the phase currents.

25. A transfer switch in accordance with claim 1 wherein said braid assembly comprises a single-piece braid.

26. A transfer switch in accordance with claim 1 wherein said braid assembly comprises a single-piece braid onto which ferrules are slipped and crimped.

27. A transfer switch for switching between power sources for a load, said transfer switch comprising:

a plurality of phase plates, each said phase plate comprising a centerline about which said phase plate is configured symmetrically;

a plurality of stationary contact pads associated with each said phase plate, each said stationary contact pad associated with a power source;

a movable contact assembly associated with each said phase plate, wherein said movable contact assembly includes a movable finger;

a shaft connecting said phase plates and upon which each said movable contact assembly is mounted for movement between said stationary contact pads associated with each said phase plate; and

a mechanical drive assembly configured to rotate said movable finger, wherein said mechanical drive assembly includes a fork assembly and a mass driver assembly, wherein said mass driver assembly and said fork assembly each comprise a plurality of stopping surfaces, said stopping surfaces configured to cooperate in controlling motion of said mechanical drive assembly.

28. A transfer switch for switching between power sources for a load, said transfer switch comprising:

a plurality of phase plates, each said phase plate comprising a centerline about which said phase plate is configured symmetrically;

a plurality of stationary contact pads associated with each said phase plate, each said stationary contact pad associated with a power source;

a movable contact assembly associated with each said phase plate;

a shaft connecting said phase plates and upon which each said movable contact assembly is mounted for movement between said stationary contact pads associated with each said phase plate; and

a fork assemble, wherein said fork assembly comprises an internal geometry allowing for a series of transition points based on movement of movable contacts between said stationary contact pads.