Circuit Breaker Tripping Mechanism With Lever-Assisted Release

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional trip mechanisms in circuit breakers require high locking and unlocking forces due to short force arms, which are not adequately addressed by the push force and push distance of existing trip actuators, leading to unreliable quick disconnection during abnormal conditions.

Innovation Solution

A trip mechanism with a rotatably mounted trip latch, reset lever, and locking catch, where the reset lever is configured as a force-reducing lever structure with a first and second lever arm, and the relative positions of these components allow for reduced force application through their relative rotation, ensuring efficient disconnection during abnormal conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the trip latch is made small to meet space constraints, then the circuit breaker size is reduced, but the force arm length decreases requiring greater locking and unlocking forces

Engineering Contradiction:
Improvetrip latch sizeVSAvoidlocking and unlocking forces
Core Design Contradiction:
Volume of moving objectVSForce

Solution Approach 1:

The patent introduces a reset lever as an intermediary component between the trip latch and locking catch. This reset lever acts as a force transmission mediator that redirects and amplifies the force from the trip latch to the locking catch, enabling the small trip latch to generate sufficient unlocking force through the lever mechanism without increasing its own size.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The reset lever is designed to rotate dynamically during the tripping process. It transitions from an initial position where it receives force from the trip latch to a final position where it applies amplified force to the locking catch. This dynamic rotation allows the system to transform the small force from the compact trip latch into the large force needed for unlocking.

Inventive Principle:
Principle #15Dynamics

2Length of moving object

If the trip latch force arm is shortened to reduce size, then space constraints are met, but the required tripping force increases beyond what the trip actuator can provide

Engineering Contradiction:
Improveforce arm lengthVSAvoidtripping force
Core Design Contradiction:
Length of moving objectVSForce

Solution Approach 1:

The reset lever serves as a force-amplifying intermediary that bridges the gap between the short force arm of the trip latch and the locking catch. By positioning the reset lever's rotation axis strategically, it creates a long moment arm that multiplies the force from the trip latch, enabling the trip actuator to generate sufficient tripping force even with a shortened force arm.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent resolves the force arm length limitation by transitioning to a different dimensional approach - using the reset lever to create force multiplication in a rotational dimension rather than relying solely on linear force arm length. This allows the system to achieve high tripping force through angular leverage rather than linear dimension.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Device complexity

If conventional trip mechanism structure is used, then the design is simple, but the push force and push distance of the trip actuator are insufficient to achieve reliable tripping

Engineering Contradiction:
Improvetrip mechanism structureVSAvoidtripping reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The reset lever is introduced as an essential intermediary component that transforms the insufficient push force and short push distance from the trip actuator into effective tripping action. The reset lever's rotation mechanism converts the limited linear displacement into amplified rotational motion that reliably actuates the locking catch release.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent enhances tripping reliability by introducing dynamic motion through the rotating reset lever. This dynamic mechanism allows the system to accumulate and redirect energy through rotational movement, ensuring that even limited actuator output can reliably trigger the tripping sequence under all operating conditions.

Inventive Principle:
Principle #15Dynamics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The mechanism reduces the required release force of the electromagnetic trip actuator, ensuring reliable automatic contact disconnection during leakage faults by optimizing the force application and layout within the circuit breaker.

Implementation Method 1

the reset lever is configured as a force-reducing lever structure comprising a first lever arm and a second lever arm... a first torque arm of the first pressing portion is shorter than a second torque arm of the second engagement portion

Methodology Applied
Scientific EffectLever: Lever

Data Source

PatentEP4597537A1Tripping mechanism of circuit breaker, and circuit breaker
Publication Date: 2025.08.06 XIAMEN HONGFA AUTOMOTIVE ELECTRONICS CO LTD
  • EP4597537A1 patent drawingFigure 1~2
  • EP4597537A1 patent drawingFigure 3~4
  • EP4597537A1 patent drawingFigure 5~6

AI summary

A tripping mechanism of a circuit breaker, and a circuit breaker. The tripping mechanism comprises a jump pin (17), a re-buckle (18) and a lock latch (20), which are rotatably arranged, wherein the re-buckle (18) is of a labor-saving lever structure and comprises a first lever arm (181) and a second lever arm 182); a first lap joint portion (1703) is arranged on the jump pin (17), a first press-fitting portion (1801) is correspondingly provided on the first lever arm (181); and a second lap joint portion (1803) is provided on the second lever arm ( 182), and a second press-fitting portion (2001) is correspondingly provided on the lock latch (20). The relative positions of the jump pin (17), the re-buckle (18) and the lock latch (20) are configured in such a way that, by means of relative rotation between each other, the first press-fitting portion (1801) is press-fitted to the first lap joint portion (1703) while the second press-fitting portion (2001) is press-fitted to the second lap joint portion (1803), thus the rotation of the jump pin (17) is limited, a first rotating force arm (L1) of the first press-fitting portion (1801) being smaller than a second rotating force arm (L2) of the second lap joint portion (1803).