Passive safety shield

Abstract

A safety apparatus is provided which includes a needle hub having an arm extending therefrom and an extensible frame connected to the needle hub. The extensible frame includes a proximal segment that is hingedly connected to a distal segment. The extensible frame is resiliently biased from a retracted position to an extended position, wherein the arm releasably engages the proximal segment to fix the extensible frame in a position between the retracted position and the extended position. In an alternate embodiment, the safety apparatus includes an extensible frame including a proximal segment which is hingedly connected to a distal segment. A resilient member is coupled to the proximal segment and the distal segment. The resilient member is configured to bias the extensible frame from a retracted position to an extended position. A method for infusing fluids to a subject is disclosed.

1 . A passively activated safety needle assembly comprising: 
 a needle cannula with opposite proximal and distal ends; and    a shield assembly having a safety shield slidably mounted on said needle cannula and movable from a proximal position substantially adjacent said proximal end of said needle cannula to a distal position surrounding said distal end of said needle cannula, said shield assembly further comprising a plurality of hingedly connected arms with at least two arms being hingedly connected at a hinge connection extending between said safety shield and a location in proximity to said proximal end of said needle cannula for limiting distal movement of said safety shield along said needle cannula, said shield assembly further comprising a torsion spring securably disposed at said hinge connection for urging said safety shield from said proximal position to said distal position.    
   
   
       2 . The passively activated safety needle assembly of  claim 1 , further comprising a safety cap frictionally mounted over said needle cannula and over portions of said shield assembly for holding said safety shield in said proximal position.  
   
   
       3 . The passively activated safety needle assembly of  claim 1 , further comprising a needle hub secured to said proximal end of said needle cannula, and wherein said plurality of arms comprises a distal arm articulated to said safety shield and a proximal arm articulated in proximity to said hub, said proximal and distal arms being hingedly connected to one another at said hinge connection.  
   
   
       4 . The passively activated safety needle assembly of  claim 3 , wherein said torsion spring is disposed between said hub and said proximal arm, said torsion spring urging said proximal arm about said articulation to said base for expanding said proximal and distal arms relative to one another and propelling said safety shield distally along said needle cannula.  
   
   
       5 . The passively activated safety needle assembly of  claim 4 , wherein the base further comprises a thumb grip projecting from said base at a location opposite said proximal arm.  
   
   
       6 . The passively activated safety needle assembly of  claim 3 , wherein said torsion spring is mounted at said hinged connection between said proximal and distal arms for urging said proximal and distal arms into an expanded condition and thereby driving said safety shield distally along said needle cannula.  
   
   
       7 . The passively activated safety needle assembly of  claim 3 , wherein said shield assembly further comprises a base securely mounted to said needle hub, said proximal arm being articulated to said base.  
   
   
       8 . The passively activated safety needle assembly of  claim 3 , wherein said safety cap includes a notch for slidably receiving said arms and holding said arms in a collapsed condition.  
   
   
       9 . The passively activated safety needle assembly of  claim 3 , wherein said safety shield is unitary with said distal arm.  
   
   
       10 . The passively activated safety needle assembly of  claim 3 , wherein said proximal arm is unitary with said base.  
   
   
       11 . A passively activated safety needle assembly comprising: 
 a needle assembly having a needle cannula with opposite proximal and distal ends, a needle hub securely mounted to said proximal end of said needle cannula and being configured for mounting to a medical implement;    a shield assembly having a safety shield slidably mounted on said needle cannula and movable from a proximal position adjacent said hub to a distal position surrounding said distal end of said needle cannula, said shield assembly further comprising a distal arm hingedly connected to said safety shield, a proximal arm hingedly connected to said distal arm at a hinge and a base hingedly connected to said proximal arm, said base being securely mounted to said hub of said needle assembly, said shield assembly further comprising a torsion spring secured to said hinge and mounted to at least one of said arms for moving said arms in a direction for urging said safety shield to said distal position; and    a safety cap releasably engaged over said needle cannula and over portions of said shield assembly for holding said shield assembly in said proximal position.    
   
   
       12 . A passively activated safety needle assembly comprising: 
 a needle with opposite proximal and distal ends; and    a shield assembly having a needle point guard slidably mounted on said needle and movable from a proximal position substantially adjacent said proximal end of said needle to a distal position surrounding said distal end of said needle, said shield assembly further comprising a plurality of hingedly connected arms with at least two arms being hingedly connected at a hinge connection extending between said needle point guard and a location in proximity to said proximal end of said needle for limiting distal movement of said needle point guard along said needle, said shield assembly further comprising a spring securably disposed at said hinge connection for urging said needle point guard from said proximal position to said distal position.    
   
   
       13 . The passively activated safety needle assembly of  claim 12 , further comprising a safety cap frictionally mounted over said needle and over portions of said shield assembly for holding said needle point guard in said proximal position.  
   
   
       14 . The passively activated safety needle assembly of  claim 12 , further comprising a needle hub secured to said proximal end of said needle, and wherein said plurality of arms comprises a distal arm articulated to said needle point guard and a proximal arm articulated in proximity to said hub, said proximal and distal arms being hingedly connected to one another at said hinge connection.  
   
   
       15 . The passively activated safety needle assembly of  claim 14 , wherein said spring is disposed between said hub and said proximal arm, said spring urging said proximal arm about said articulation to said base for expanding said proximal and distal arms relative to one another and propelling said needle point guard distally along said needle.  
   
   
       16 . The passively activated safety needle assembly of  claim 15 , wherein the base further comprises a thumb grip projecting from said base at a location opposite said proximal arm.  
   
   
       17 . The passively activated safety needle assembly of  claim 14 , wherein said spring is mounted at said hinged connection between said proximal and distal arms for urging said proximal and distal arms into an expanded condition and thereby driving said needle point guard distally along said needle.  
   
   
       18 . The passively activated safety needle assembly of  claim 14 , wherein said shield assembly further comprises a base securely mounted to said needle hub, said proximal arm being articulated to said base.  
   
   
       19 . The passively activated safety needle assembly of  claim 14 , wherein said safety cap includes a notch for slidably receiving said arms and holding said arms in a collapsed condition.  
   
   
       20 . The passively activated safety needle assembly of  claim 14 , wherein said needle point guard is unitary with said distal arm.  
   
   
       21 . The passively activated safety needle assembly of  claim 14 , wherein said proximal arm is unitary with said base.  
   
   
       22 . A passively activated safety needle assembly comprising: 
 a needle assembly having a needle with opposite proximal and distal ends, a needle hub securely mounted to said proximal end of said needle and being configured for mounting to a medical implement;    a shield assembly having a needle point guard slidably mounted on said needle and movable from a proximal position adjacent said hub to a distal position surrounding said distal end of said needle, said shield assembly further comprising a distal arm hingedly connected to said needle point guard, a proximal arm hingedly connected to said distal arm at a hinge and a base hingedly connected to said proximal arm, said base being securely mounted to said hub of said needle assembly, said shield assembly further comprising a spring secured to said hinge and mounted to at least one of said arms for moving said arms in a direction for urging said needle point guard to said distal position; and    a safety cap releasably engaged over said needle and over portions of said shield assembly for holding said shield assembly in said proximal position.