Crossbow Trigger Latch Mechanism Prevents Dry-Firing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing crossbow mechanisms lack efficient and reliable methods for drawing, cocking, and triggering, often relying on tension in a rope that can break or become unusable, and do not adequately prevent unintentional firing or dry-firing.
Innovation Solution
A mechanism comprising a stationary subassembly, a reciprocating subassembly, and a winch subassembly with a spool and crank handle, where the reciprocating subassembly is engaged with a mainframe slot, allowing movement between brace and drawn positions, and includes a trigger latch to hold the subassembly in place without rope tension, and safety features to prevent accidental firing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a rope tension mechanism is used for drawing and cocking the crossbow, then the drawing and cocking function is achieved, but the rope may break or become unusable leading to reliability issues
Solution Approach 1:
The patent removes the rope from the mechanism entirely, replacing it with a direct mechanical linkage between the trigger and the sear component. This extraction eliminates the rope's reliability issues while maintaining the drawing and cocking function through alternative mechanical means.
Solution Approach 2:
The patent replaces the rope-based tension mechanism with a direct mechanical linkage system involving the trigger, actuator, and sear. This substitution provides a more reliable connection that cannot break or become unusable like rope, while achieving the same functional outcome.
2Reliability
If traditional trigger mechanisms are used, then firing function is achieved, but unintentional firing or dry-firing cannot be prevented
Solution Approach 1:
The patent incorporates a safety mechanism that prevents the sear from disengaging unless specific conditions are met. The trigger mechanism includes preliminary safety checks that block unintentional firing paths, ensuring that the crossbow can only be fired when properly assembled with a bolt in place.
Solution Approach 2:
The mechanism requires preliminary assembly steps where the bolt must be inserted and properly positioned before the trigger mechanism can function. This preliminary action ensures that dry-firing is prevented, as the safety interlock will not allow firing without a bolt in place.
3Stability of the object's composition
If the reciprocating subassembly is held in place by rope tension, then the drawn position is maintained, but the system becomes vulnerable to rope failure
Solution Approach 1:
The patent removes the rope entirely from the position-maintaining function, replacing it with a direct mechanical engagement between the trigger latch and the reciprocating subassembly. This eliminates the rope's vulnerability to breaking while maintaining the stability of the drawn position.
Solution Approach 2:
The patent employs a cam mechanism with curved surfaces that provide continuous contact and stable positioning of the reciprocating subassembly. The curved geometry ensures reliable mechanical engagement that maintains position without relying on tensioned rope elements.
Data Source
AI summary
An inventive mechanism includes stationary, reciprocating, winch, and stock subassemblies. The winch subassembly is mounted on the stock subassembly; the stationary subassembly is mounted at the rear of a slotted mainframe of the stock subassembly; the reciprocating subassembly moves along the mainframe between forward brace and rearward drawn positions. The winch subassembly takes up a rope to cause rearward movement of the reciprocating subassembly and lets out the rope to permit forward movement. The reciprocating subassembly includes a body engaged with the slot, a catch, and a sear. The stationary subassembly includes a trigger and an actuator. In the drawn position and retaining a bowstring, trigger movement causes actuator movement, which causes sear movement, which permits catch movement, which releases the bowstring. In its latched position, a trigger latch obstructs forward movement of the reciprocating subassembly from the drawn position; in its unlatched position, it permits that forward movement.