Gas blast circuit breaker
AssigneeSprecher & Schuh AG
InventorRichard Thaler
Life of this patent
Estimating the term…
Abstract
A gas blast circuit breaker has fixed and movable contact sets, the latter mounted on a cylinder slidable on a fixed piston to generate a gas blast on separation of the contact sets. Each contact set consists of radially inner and outer contacts, the inner contacts separating later than the outer. A gas blast nozzle mounted on the cylinder and between the radially inner and outer movable contacts has a throat downstream of the inner contact, communicating with the interior of the cylinder by way of an inner duct containing the inner contact, and an annular outer duct, so arranged that on separation of the contacts relatively cool fresh quenching gas is directed through the inner duct over the inner contact and arc.
Claims12
A gas blast circuit breaker having a stationary set of contact means and a movable set of contact means, each said set comprising radially inner and radially outer contact means, the radially inner contact means of the two sets being arranged to interengage and the radially outer contact means of the two sets being arranged to interengage;
- actuating means for moving the movable set of contact means, the radially outer contact means being arranged to be disengaged before the radially inner contact means disengage;
- and a blast nozzle of the insulating material, arranged to move with the movable contacts and having inlet means for receiving a pressurized quenching gas from a gas pressure chamber, which nozzle has a narrowest portion thereof disposed downstream with respect to the direction of the quenching gas blast of the end of the radially inner movable contact means and disposed between the radially inner and radially outer movable contact means, said blast nozzle comprising upstream of its said narrowest portion a radially inner first annular longitudinal quenching gas duct encircling the radially inner movable contact means whereby quenching gas in said first duct will be directly impinge on and flow along the said inner movable contact means, and a coaxially outer second annular longitudinal quenching gas duct, merging with said first annular quenching gas duct in the range of the free end of the radially inner movable contact means, further means being provided at the inlet end of said first annular longitudinal duct for preventing direct back flow from said first annular duct into said gas pressure chamber.
Dependencies are inferred from the claim text.