Needle mechanism module for drug infusion device

Abstract

A needle mechanism module for drug infusion device, includes: an infusion needle, provided with a front end and a rear end; a needle holder; provided with at least an auxiliary engaging part, the infusion needle being arranged on the needle holder, when the needle holder is at the working position, the rear end is inserted into the skin, and the front end is connected to the drug storage unit of the infusion device; an auxiliary engaging portion, arranged within the infusion device, engaged with the auxiliary engaging part to limit the needle holder at the working position; and a stopper, arranged on the housing of the infusion device, when the needle mechanism module is at intermediate position, the stopper limits the position of the needle holder, the front end is connected with the drug storage unit of the infusion device, to balance the internal and external pressures.

1 . A needle mechanism module for drug infusion device, comprising:
 an infusion needle, provided with a front end and a rear end;   a needle holder, provided with at least an auxiliary engaging part, wherein the infusion needle is arranged on the needle holder, when the needle holder is at a working position, the rear end is inserted into a skin, and the front end is connected to a drug storage unit of the infusion device;   an auxiliary engaging portion, arranged within the infusion device, engaged with the auxiliary engaging part to limit the needle holder at the working position; and   a stopper, arranged on a housing of the infusion device, when the needle holder is at a non-working position, the stopper limits a position of the needle holder.   
     
     
         2 . The needle mechanism module for drug infusion device of  claim 1 , wherein the needle holder includes a guide post which moves along a guide cavity that is provided in the housing of the infusion device. 
     
     
         3 . The needle mechanism module for drug infusion device of  claim 2 , wherein the auxiliary engaging part is arranged on the guide post or under a top of the needle holder, and the auxiliary engaging part or the auxiliary engaging portion comprises a hook, a hole, a block, or a slot. 
     
     
         4 . The needle mechanism module for drug infusion device of  claim 1 , wherein a slider is provided on the stopper while the housing is provided with a sliding groove, the slider is arranged in the sliding groove, and the slider slides along the sliding groove to make the stopper engage or release the needle holder. 
     
     
         5 . The needle mechanism module for drug infusion device of  claim 4 , wherein at least one engaging arm is provided on the stopper. 
     
     
         6 . The needle mechanism module for drug infusion device of  claim 5 , further comprising a first engaging portion, wherein the first engaging portion is provided on the engaging arm to engage with the needle holder to limit the position of the needer holder. 
     
     
         7 . The needle mechanism module for drug infusion device of  claim 6 , wherein a side surface of the guide post is provided with convex or concave, the engaging arm engaged with the convex or concave to limit the position of the needle holder. 
     
     
         8 . The needle mechanism module for drug infusion device of  claim 7 , wherein a thickness of a forward end of the stopper is smaller than a thickness of a backward end of the stopper. 
     
     
         9 . The needle mechanism module for drug infusion device of  claim 8 , wherein the stopper is provided with an unlock rod. 
     
     
         10 . The needle mechanism module for drug infusion device of  claim 9 , it further comprising a unlock hole, wherein an opening of the unlock hole is provided on the top of the needle holder, a top of the housing, or a side wall of the housing, the unlock rod release engagement of the auxiliary engaging part and the auxiliary engaging portion through the unlock hole. 
     
     
         11 . The needle mechanism module for drug infusion device of  claim 10 , wherein the opening of the unlock hole is provided on the top of the needle holder, and longitudinal directions of the unlock hole and the guide post are parallel to each other. 
     
     
         12 . The needle mechanism module for drug infusion device of  claim 3 , wherein a mode to release and reset the needle holder comprises a pop-up mode or a pushing mode. 
     
     
         13 . The needle mechanism module for drug infusion device of  claim 12 , it further comprising a spring, arranged in the guide cavity, which is compressed by the needle holder when the needle holder is in the working position. 
     
     
         14 . The needle mechanism module for drug infusion device of  claim 12 , it further comprising a locking lever, wherein the auxiliary engaging part is a hole or a slot, a first end of the locking lever is movably arranged inside the auxiliary engaging part while a second end of the locking lever is engaged with the auxiliary engaging portion, a fulcrum of the locking lever is arranged between the first end and the second end of the locking lever, and the second end is pushed by the unlock rod to move a distance to release engagement of the auxiliary portion and the locking lever and release the needle holder.