Patent attributes
A retractable blade knife with an opening assisted mechanism has a handle, a blade mounted in the handle, an extending assembly mounted between the blade and the handle. At least one detent formed at a spine edge of the blade. The extending assembly has a positioning frame, a slider mounted beside the positioning frame and attached to the blade and a spring attached to the positioning frame and the slider. The positioning frame has a resilient rod selectively abutting the spine edge and a proximal end of the blade. The blade should be pushed manually a certain distance to allow the spine edge of the blade to push a rear end of the resilient rod outwardly. When the detent of the blade and a lock protrusion of the slider both depart from the resilient rod of the positioning frame, the spring may further pull the slider to move together with the blade to stretch out the blade. Thus, the spring helps the blade to be extended quickly and the extending assembly also prevents the blade from being retracted or extended accidentally. Therefore, the retractable blade knife with an opening assisted mechanism is used safely and conveniently.