Non-rotary, pull-pull interphase gang-style linkage structure for high voltage dead tank breaker

1. Linkage structure for connection between an operating mechanism and at least one actuating assembly of a circuit breaker for opening and closing a movable electrical contact of a pole assembly associated with the actuating assembly, the linkage structure comprising:

at least one lever constructed and arranged to connect with the at least one actuating assembly,

at least one connection rod coupled to the lever and associated with a close spring for closing the electrical contact, and

at least one spring structure coupled to the lever, the spring structure including at least one open spring providing a spring force on the lever for opening the electrical contact while always maintaining the connection rod in tension.

2. The linkage structure of claim 1 , wherein the open spring is a coil spring.

3. The linkage structure of claim 2 , wherein the spring structure includes a link having one end coupled to an end of the open spring and another end coupled to the lever.

4. The linkage structure of claim 3 , further comprising a pin coupling the link to the lever.

5. The linkage structure of claim 1 , in combination with the operating mechanism and the actuating assembly.

6. The combination of claim 5 , wherein the actuating assembly comprises at least one bell crank assembly coupled to the lever.

7. The combination of claim 6 , wherein the circuit breaker is a high voltage, dead tank circuit breaker having three pole assemblies and a bell crank assembly coupled with the movable electrical contact of each pole assembly, wherein

a lever is coupled with each bell crank assembly,

two connection rods interconnect the levers, and

a rod is coupled between one of the levers and the close spring so that the bell cranks can be operated simultaneously to close the movable electrical contact of each pole assembly.

8. The combination of claim 7 , wherein a spring structure is provided at each pole assembly, a link of each spring structure has one end coupled to an end of an associated open spring and with another end coupled to the associated lever.

9. The combination of claim 8 , wherein the open springs are constructed and arranged such that a total spring force of the open springs opposes a spring force of the close spring.

10. The combination of claim 9 , wherein the open springs are constructed and arranged to cause the levers and thus the bell crank assemblies to move simultaneously to open the movable electrical contact of each pole assembly.

11. The combination of claim 7 , wherein each connection rod is coupled to an associated lever by a pin connection.

12. A method of maintaining pretension on linkage structure connected between an operating mechanism and at least one actuating assembly of a circuit breaker, the method including the steps of:

coupling at least one lever with the at least one actuating assembly for opening and closing a movable electrical contact of a pole assembly associated with the actuating assembly,

coupling at least one connection rod to the lever,

associating the connection rod with a close spring for closing the electrical contact, and

coupling at least one spring structure to the lever, the spring structure including at least one open spring providing a spring force on the lever for opening the electrical contact while always maintaining the connection rod in tension.

13. The method of claim 12 , wherein the actuating assembly is a bell crank assembly and the lever is coupled to the bell crank assembly via crank link.

14. The method of claim 12 , wherein the open spring is a coil spring and wherein the spring structure includes a link having one end coupled to an end of the open coil spring and another end coupled to the lever.

15. The method of claim 13 , wherein the circuit breaker is a high voltage, dead tank circuit breaker having three pole assemblies and a bell crank assembly coupled with the movable electrical contact of each pole assembly, wherein a lever is coupled with each bell crank assembly, the method further comprising:

interconnecting the levers by two connection rods, and

coupling a rod between one of the levers and the close spring so that the bell cranks can be operated simultaneously to close the movable electrical contact of each pole assembly.

16. The method of claim 15 , wherein a spring structure is provided at each pole assembly, with each spring structure providing one open spring, the method including:

coupling an end of a link of each spring structure to an end of an associated open spring and coupling another end of the link to the associated lever.

17. The method of claim 16 , wherein the open springs are provided such that a total spring force of the open springs opposes a spring force of the close spring.

18. The combination of claim 16 , wherein the open springs are provided to cause the levers and thus the bell cranks to move simultaneously to open the movable electrical contact of each pole assembly.