| 摘要 |
A puffer type circuit breaker is provided with a pump means consisting of a piston and a cylinder for producing a blast of arc-extinguishing gas. The movable arcing contact of the circuit breaker and the cylinder are connected to an operating device via a rod axially displaceable through an opening in the piston. In the piston there is arranged a check valve, which upon closing of the breaker opens for subsequent filling of the pump chamber with arc-extinguishing gas. The check valve comprises a guiding sleeve of a ductile material (e.g. polyetrafluoro ethylene), which sealingly surrounds the rod and is fixed with a certain axial mobility in the opening in the piston arranged for the rod. The sleeve controls (or is fixedly connected to) the movable valve means of the check valve and, in addition, serves as a seal and a bearing between the rod and the piston.
|
