Utility Knife

Abstract

A utility knife including a handle, a blade, a first blade holder, and a spare blade holder. The spare blade holder is pivotal with respect to the handle between an open position where the recess is exposed to allow a spare blade to be removed from the spare blade holder and a closed position where the recess is within a slot of the handle to inhibit removal of the spare blade from the spare blade holder. The spare blade holder further including a cam surface and the cam surface of the spare blade holder engages a cam surface of the handle when the spare blade holder is in the closed position to urge the spare blade holder in a direction from a first longitudinal side of the handle toward a second longitudinal side of the handle to allow the first blade holder to pivot between extended and folded positions.

What is claimed is: 
     
         1 . A utility knife comprising:
 a handle that comprises a first longitudinal side, a second longitudinal side opposite the first longitudinal side, a top side, a bottom side, and a slot that extends through the bottom side, the slot between the first and second longitudinal sides;   a blade;   a blade holder, the blade removably coupled to the blade holder, the blade holder pivotable with respect to the handle between an extended position where the blade is exposed and configured to cut a work-piece and a folded position where the blade is within the slot of the handle, the blade holder comprising a first notch and a second notch; and   a locking mechanism comprising:
 a push button movable between a locked position and an unlocked position, the blade holder pivotable with respect to the handle between the extended and folded positions when the push button is in the unlocked position and the blade holder is held from pivotal movement relative to the handle when the push button is in the locked position, the push button comprising a first portion of a first diameter and a second portion of a second diameter that is larger than the first diameter and a frusto-conical portion between the first and second portions, the second portion of the push button is received in the first notch of the blade holder to hold the blade holder in the extended position and the second portion of the push button is received in the second notch of the blade holder to hold the blade holder in the folded position, and 
 a coil spring that biases the push button toward the locked position. 
   
     
     
         2 . The utility knife of  claim 1 , wherein the blade holder further comprises a third notch between the first notch and the second notch, wherein the second portion of the push button is received in the third notch of the blade holder to hold the blade holder in an intermediate position between the folded and extended positions. 
     
     
         3 . The utility knife of  claim 1 , wherein the push button comprises a recess and the handle comprises a recess, wherein an end of the spring is received within the recess of the handle and an opposite end of the spring is received within the recess of the push button. 
     
     
         4 . The utility knife of  claim 1 , wherein the blade holder comprises a front end, a back end, a top edge, and a bottom edge, wherein the blade holder comprises an upwardly angled surface on the top edge at the front end of the blade holder. 
     
     
         5 . A utility knife comprising:
 a handle that comprises a first longitudinal side, a second longitudinal side opposite the first longitudinal side, a top side, a bottom side, and a slot that extends through the bottom side, the slot between the first and second longitudinal sides;   a blade;   a blade holder, the blade removably coupled to the blade holder, the blade holder pivotable with respect to the handle between an extended position where the blade is exposed and configured to cut a work-piece and a folded position where the blade is within the slot of the handle, the blade holder comprising a first notch and a second notch; and   a locking mechanism comprising:
 an actuator movable between a locked position and an unlocked position, the blade holder pivotable with respect to the handle between the extended and folded positions when the actuator is in the unlocked position and the blade holder is held from pivotal movement relative to the handle when the actuator is in the locked position, the actuator comprising a first portion of a first diameter and a second portion of a second diameter that is larger than the first diameter, the second portion of the actuator is received in the first notch of the blade holder to hold the blade holder in the extended position and the second portion of the actuator is received in the second notch of the blade holder to hold the blade holder in the folded position, and 
 a biasing element that biases the actuator toward the locked position. 
   
     
     
         6 . The utility knife of  claim 5 , wherein the blade holder further comprises a third notch between the first notch and the second notch, wherein the second portion of the actuator is received in the third notch of the blade holder to hold the blade holder in an intermediate position between the folded and extended positions. 
     
     
         7 . The utility knife of  claim 5 , wherein the actuator comprises a recess and the handle comprises a recess, wherein an end of the biasing element is received within the recess of the handle and an opposite end of the biasing element is received within the recess of the push button. 
     
     
         8 . The utility knife of  claim 7 , wherein the handle comprises a post within the recess to stabilize the biasing element. 
     
     
         9 . The utility knife of  claim 5 , wherein the blade holder comprises a front end, a back end, a top edge, and a bottom edge, wherein the blade holder comprises an upwardly angled surface on the top edge at the front end of the blade holder. 
     
     
         10 . The utility knife of  claim 5 , wherein the actuator comprises a frusto-conical portion between the first and second portions. 
     
     
         11 . The utility knife of  claim 5 , wherein the biasing element comprises a spring. 
     
     
         12 . The utility knife of  claim 5 , wherein the actuator comprises a push button. 
     
     
         13 . A utility knife comprising:
 a handle that comprises a first longitudinal side, a second longitudinal side opposite the first longitudinal side, a top side, a bottom side and a slot between the first and second longitudinal sides;   a blade;   a blade holder, the blade removably coupled to the blade holder, the blade holder pivotable with respect to the handle between an extended position where the blade is exposed and a folded position where the blade is within the slot of the handle, the blade holder comprising a first notch and a second notch; and   a locking mechanism comprising:
 an actuator movable between a locked position and an unlocked position, the blade holder pivotable with respect to the handle between the extended and folded positions when the actuator is in the unlocked position and the blade holder is held from pivotal movement relative to the handle when the actuator is in the locked position, the actuator comprising a first portion of a first diameter and a second portion of a second diameter that is larger than the first diameter, the second portion of the actuator is received in the first notch of the blade holder to hold the blade holder in the extended position and the second portion of the actuator is received in the second notch of the blade holder to hold the blade holder in the folded position, and 
 a biasing element that biases the actuator toward the locked position. 
   
     
     
         14 . The utility knife of  claim 13 , wherein the second portion actuator comprises a frusto-conical external surface. 
     
     
         15 . The utility knife of  claim 13 , wherein the actuator comprises a frusto-conical portion between the first and second portions. 
     
     
         16 . The utility knife of  claim 13 , wherein the blade holder further comprises a third notch between the first notch and the second notch, wherein the second portion of the actuator is received in the third notch of the blade holder to hold the blade holder in an intermediate position between the folded and extended positions. 
     
     
         17 . The utility knife of  claim 13 , wherein the actuator comprises a recess and the handle comprises a recess and a post, wherein an end of the biasing element is received within the recess of the push button and an opposite end of the biasing element is received within the recess of the handle around the post. 
     
     
         18 . The utility knife of  claim 13 , wherein the blade holder comprises a front end, a back end, a top edge, and a bottom edge, wherein the blade holder comprises an upwardly angled surface on the top edge at the front end of the blade holder. 
     
     
         19 . The utility knife of  claim 13 , wherein the biasing element comprises a spring and the actuator comprises a push button. 
     
     
         20 . The utility knife of  claim 13 , wherein the slot extends through the bottom side of the handle.