Mechanical Self-Percussion Fuze with Wind Turbine Arming
Solution Overview
Problem
Current mechanical fuzes for non-gyratory ammunition lack a reliable and adaptive mechanism to ensure a safe and consistent arming distance and safety distance, independent of the ammunition's load, as they fail to effectively utilize the relative movement of air during flight as a second physical phenomenon.
Innovation Solution
A mechanical fuze with a wind turbine driven by the relative air movement during flight, generating rotational torque to regulate the transition from a safe to an armed state, incorporating a locking system and inertial socket to ensure independence from linear acceleration and centrifugal forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a wind turbine is used to achieve the second storage safety device, then the arming distance becomes adaptive to different loads, but the device complexity increases
Solution Approach 1:
The wind turbine serves multiple functions: it acts as both the second storage safety device trigger and the arming mechanism for the fuze. By integrating these functions into a single component, the patent achieves adaptive arming distance for different loads without proportionally increasing device complexity
Solution Approach 2:
The wind turbine converts the dynamic aerodynamic forces encountered during flight into rotational motion, which then triggers the safety device and arming sequence. This dynamic response allows the system to adapt to varying flight conditions and loads automatically
2Reliability
If mechanical solutions like finger detection or gas pressure detection are used, then the device structure remains simple, but the reliability of achieving independent safety events is insufficient
Solution Approach 1:
The wind turbine acts as an intermediary mechanism that translates aerodynamic forces into mechanical action. It mediates between the flight conditions and the safety device activation, providing a reliable and independent trigger mechanism that is distinct from the linear acceleration event
Solution Approach 2:
The patent replaces electronic or complex detection systems (finger detection, gas pressure sensors) with a purely mechanical wind turbine-based system. This substitution maintains simplicity while achieving the required reliability through passive mechanical response to aerodynamic forces
3Reliability
If no adaptive function is integrated, then the device complexity remains low, but the safety distance becomes inconsistent across different loads
Solution Approach 1:
The wind turbine's rotational speed and torque output naturally vary with flight speed and aerodynamic conditions. This parameter change allows the system to automatically adjust the arming timing to maintain consistent safety distances regardless of the specific load or flight conditions
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 solution provides a reliable and efficient mechanism that maintains a consistent safety and arming distance across varying loads, ensuring personnel safety by utilizing air movement to achieve the second storage security lock, meeting standards like Stanag 4187.
Implementation Method 1
a wind turbine arranged to be driven in rotation by the relative movement of the air with respect to the ammunition during its flight, and to generate the rotational torque necessary for the operation of said mechanism
Implementation Method 2
The effect of the linear acceleration of the ammunition linked to starting firing constitutes the first physical phenomenon which can be used to remove a first storage safety device
Data Source
AI summary
The invention relates to a mechanical self-percussion fuze (1) for a non-spinning round, having a firing pin (14) disposed along a central axis (A), a primer (17′) provided in a primer holder (17) that is movable about an axis of rotation (B) that is parallel and off-centre with respect to the central axis (A) between a storage position in which the primer (17′) is off-centre with respect to the firing pin (14) and an armed position in which the primer (17′) is aligned with the firing pin (14), and safety devices coupled to the primer holder (17) in order to keep the fuze (1) in a safe state until at least two mutually independent physical phenomena linked to the firing of the round occur. The fuze (1) has a wind turbine (11) designed to be driven in rotation by the relative movement of the air during the flight of the round and to transmit this rotational movement to the primer holder (17) only after the safety devices have been removed.