Safety scalpel

Abstract

A scalpel enabling both safe blade engagement or disengagement and safe passing among personnel during surgical procedures. The blade arm assembly of the scalpel is positionable in three positions, including a retracted position, an operational extended position and a fully extended position for engagement and disengagement of the blade.

1 . A scalpel handle assembly for use with a replaceable scalpel blade, the assembly comprising:
 (a) a handle comprising an elongated body, and   (b) a blade carrier assembly comprising:
 (i) a blade arm comprising a blade tang positionable relative to the handle alternatively:
 1. with the blade withdrawn entirely into the handle, 
 2. with the blade projecting from the handle with a proximal blade end within the handle thereby retaining the blade on the tang, or 
 3. with the blade entirely outside the handle. 
 
   
   
   
       2 . A scalpel handle assembly for use with a replaceable scalpel blade, the assembly comprising:
 (a) a handle comprising an elongated body penetrated by a first longitudinal slot open to the outside of the handle, and a pair of opposed longitudinal slots transverse to the first slot, and   (b) a blade carrier assembly comprising:
 (i) a blade arm comprising a blade tang attached to an arm body positionable within the first slot, and 
 (ii) a spring associated with the blade arm to secure the blade arm in a selected one of two positions with the blade projecting from the handle for use or retracted into the handle for safety. 
   
   
   
       3 . The scalpel handle assembly of  claim 2 , wherein a pin is received in a first detent when the blade arm is in the blade projecting position and in a second detent when the blade arm is in the safety position. 
   
   
       4 . The scalpel handle assembly of  claim 2 , wherein a button or knob facilitates manipulation of the pin. 
   
   
       5 . The scalpel handle assembly of  claim 2 , wherein the pin is secured to the spring and is received in one of two detents in the handle. 
   
   
       6 . The scalpel handle assembly of  claim 3 , wherein a transition between the second detent and a side of the slot is more gradual than the transition between the first detent and a side of the slot, requiring an increased lateral force to disengage from the blade projecting position to a fully projected position. 
   
   
       7 . A surgical scalpel comprising:
 (a) a blade arm assembly that slides within a handle,   (b) the handle comprising a transverse slot that receives the blade arm assembly so that when a portion of a blade attached to the blade arm assembly is located in the slot the blade is secured to a blade arm assembly; the blade arm assembly comprising three positions within the handle, including:
 (i) a fully retracted position, 
 (ii) a protruding operational position, and 
 (iii) a fully extended position for engaging and disengaging a blade. 
   
   
   
       8 . The scalpel of  claim 7 , wherein the blade arm assembly further comprises a blade arm, a button assembly and a spring. 
   
   
       9 . The scalpel of  claim 8 , wherein the spring is a bi-cantilever element. 
   
   
       10 . The scalpel of  claim 7 , wherein the wherein the handle further comprises:
 (a) a first detent that captures the button assembly to lock the blade carrier in a retracted position and   (b) a second detent that captures the button assembly to lock the blade carrier in an extended operational position and   wherein extending the blade carrier beyond the second detent extends the blade arm sufficiently to allow disengagement or engagement of a blade.   
   
   
       11 . The scalpel of  claim 8 , wherein depression of the button assembly permits advancement of the blade arm assembly from a retracted position to an extended position. 
   
   
       12 . The scalpel of  claim 10 , wherein engagement of the button assembly with either the first or second detent produces an audible sound. 
   
   
       13 . The scalpel of  claim 7 , wherein the handle further comprises ridges. 
   
   
       14 . The scalpel of  claim 9 , wherein a free end of a section of the bi-cantilever element is shaped to fit around a curved end of a second cantilever section, thereby allowing for a spring-like action limited in its inward travel by the contact of the two cantilever sections and as they are squeezed toward each other. 
   
   
       15 . The scalpel of  claim 8 , wherein the button assembly further comprises a button and pin. 
   
   
       16 . The scalpel of  claim 15  wherein the button and pin are integral to the cantilever spring. 
   
   
       17 . The scalpel of  claim 7 , wherein the scalpel is formed from materials comprising aluminum, stainless steel, titanium or plastic. 
   
   
       18 . The scalpel of  claim 10 , wherein a transition between the second detent and a side of the slot is more gradual than the transition between the first detent and a side of the slot, requiring an increased lateral force to disengage from the blade projecting position to a fully projected position.