Low-voltage protective circuit breaker with a forked locking lever

US4392036A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Werner Troebel · Berlin, DE
• Martin Böttcher · Berlin, DE

Key dates

• Filing date: Aug 31, 1981
• Grant date: Jul 5, 1983
• Expiry date: Aug 31, 2001

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01H71/525
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

A low-voltage circuit breaker has a locking lever to prevent transfer of the circuit breaker handle entirely into its "off" position if the movable contact is blocked in its "on" position by being welded to the fixed contact. The locking lever is rotatably mounted on the control shaft, which is pivotally moved by a drive lever which is connected to the control shaft by a toggle lever system including two toggle levers and a toggle hinge pin joining them together. The fork arms embrace a working surface on the drive lever and the toggle hinge pin. The working surface and the hinge pin are spaced closer together than the arms when the circuit breaker handle is in its "on" position to allow only partial movement of the handle toward its "off" position unless the movable contact is free to move to its "off" position before the locking lever pivots to a position in which it engages both the working surface and the toggle hinge pin. The locking lever can be formed as a double lever with a connecting web.