Intravenous catheter introducing device

An intravenous catheter introducing device comprising:

• a barrel having front and rear open ends opposite to each other in a longitudinal direction, and a surrounding barrel wall which interconnects said front and rear open ends, said surrounding barrel wall including a smaller-diameter wall portion and a larger-diameter wall portion which are opposite to each other in the longitudinal direction and which are respectively proximate to said front and rear open ends, said surrounding barrel wall having an inner barrel wall surface which surrounds an axis in the longitudinal direction and which confines a passage that is communicated with said front and rear open ends, and an outer barrel wall surface opposite to said inner barrel wall surface in radial directions relative to the axis, said outer barrel wall surface having an access hole which is formed in said larger-diameter wall portion and which extends through said inner barrel wall surface;
• a needle cannula having a front segment terminating at a tip end, and a rear connecting end opposite to said front segment along the axis;
• a needle hub including a front holding portion and a rear shell portion disposed opposite to each other along the axis, said front holding portion being surrounded by said smaller-diameter wall portion, said rear shell portion being inserted into said passage from said rear open end, and being slidable relative to said larger-diameter wall portion along the axis between front and rear positions which are respectively proximate to said front open end and said rear open end, said front holding portion holding said rear connecting end of said needle cannula such that, when said rear shell portion is in the front position, said needle cannula is placed in a position of use, where said front segment extends forwardly of said front open end for ready use, and when said rear shell portion is in the rear position, said needle cannula is placed in a disposal position, where said front segment retreats into said passage, said rear shell portion surrounding the axis and extending away from said front holding portion to terminate at a retained end, said needle hub further including an intermediate viewing-window portion which is interposed between said front holding portion and said rear shell portion and which defines a blood-flow passage that is in fluid communication with said needle cannula;
• a biasing member which is interposed between said rear shell portion and said inner barrel wall surface, and which is disposed to bias said rear shell portion toward the rear position, said access hole being disposed in the vicinity of said retained end in the position of use such that, by accessing said retained end through said access hole, said retained end is enabled to be held against the biasing action of said biasing member;
• and
• an easy release unit including
• an engaging wall segment configured to attach to said outer barrel wall surface,
• left and right squeezed wall segments which extend from said engaging wall segment to be outboard to said outer barrel wall surface, and which are opposite to each other in a first direction transverse to the longitudinal direction, said left and right squeezed wall segments being configured to extend in a second direction transverse to both the longitudinal direction and the first direction, and to terminate at left and right joint regions, respectively, said left and right squeezed wall segments being made of a flexible material such that, upon being squeezed towards each other in the first transverse direction to thereby be placed in an actuated position, where said left and right joint regions are closer to each other, each of said left and right wall segments acquires a biasing force which biases said left and right wall segments towards a normal position, where said left and right joint regions are remote from each other, and
• left and right latch members respectively having left proximate and distal segments opposite to each other, and right proximate and distal segments opposite to each other, said left and right proximate segments being disposed to couple with said right and left joint regions, respectively, such that said left and right proximate segments are moved respectively with said right and left joint regions in the first direction, said left and right distal segments being configured such that, when said left and right proximate segments are respectively moved with said right and left joint regions to the actuated position, said left and right distal segments are moved away from each other in the first direction so as to steer clear of said retained end through said access hole, thereby permitting said biasing member to bias said rear shell portion towards the rear position.