Resettable Needle Cover Assembly With Low-Power Mechanical Locking

The patent replaces the purely electromagnetic locking system with a hybrid system that combines electromagnetic actuation (solenoid) with a mechanical spring-based locking mechanism. The spring-loaded locking member provides the holding force to maintain the locked state without continuous power consumption, while the solenoid only consumes power momentarily to initiate the unlocking action. This substitution of continuous electromagnetic force with mechanical spring force resolves the contradiction between reusability and power consumption.

The electromagnetic solenoid operates in a periodic manner rather than continuously - it is activated only when unlocking is required, while the mechanical spring maintains the locked state between activations. This periodic electromagnetic action combined with continuous mechanical action reduces overall power consumption while maintaining the reusable functionality of the device.

The patent replaces the requirement for continuous high electromagnetic force with a mechanical spring system that provides continuous locking force without power consumption. The spring-loaded locking member physically prevents retraction of the needle guard with reliable mechanical force, while the electromagnetic solenoid only needs to provide brief intermittent force to release the lock when needed. This resolves the contradiction by using mechanical force for reliable locking and minimal electromagnetic force only for unlocking operations.

The spring mechanism is pre-loaded to store mechanical energy that provides the locking force before any electromagnetic action is required. This beforehand mechanical preparation ensures reliable locking without needing continuous electromagnetic power, as the spring is already positioned to provide the necessary restraining force on the locking member.