Dual mode ratchet pruners

Abstract

Pruners and loppers have dual mode operation in that the blade is closed with a single squeeze or with multiple squeezes and a rotatable selector selects the desired mode. The blade has a rocker arm with ratchet teeth formed in a window in the arm. The scissor handle has a radius arm which ends in a pawl which can engage the ratchet nearer the pivot axis of the blade or further from it.

1 . A dual mode cutting tool including a first handle having a hand grip and a jaw member, a cutting member pivotally coupled to the first handle intermediate the hand grip and the jaw member, and a second handle pivotally coupled to the first handle, wherein the cutting member has a blade arranged for engagement with the jaw member and a rocker arm with a plurality of ratchet teeth extending away from the pivot, the cutting tool further including a pawl linkage from the second handle to the rocker arm and a mode selector that acts upon the linkage to control a position of engagement of the linkage with the ratchet teeth when the tool is operated by manipulation of the handles. 
     
     
         2 . A dual mode cutting tool according to  claim 1  wherein:
 the mode selector is configurable in a first mode wherein the pawl linkage is arranged to apply force to those of the ratchet teeth nearest the blade pivot, and in a second mode position wherein the pawl linkage is arranged to apply force to those of the ratchet teeth furthest from the blade pivot, when the tool is operated by manipulation of the handles. 
 
     
     
         3 . A dual mode cutting tool according to  claim 2  further including a spring acting between the pawl linkage and said second handle to bias said pawl linkage toward engagement with those ratchet teeth nearest the blade pivot. 
     
     
         4 . A dual mode cutting tool according to  claim 1  wherein the rocker arm has a ratchet window that forms said ratchet teeth and and the pawl linkage includes a pawl pin that projects through said ratchet window for engagement between the pawl linkage and rocker arm. 
     
     
         5 . A dual mode cutting tool according to  claim 2  wherein said mode selector includes a cam which bears against the pawl linkage to effect said control thereof in accordance with the first or second mode position configuration of the selector. 
     
     
         6 . A dual mode cutting tool according to  claim 5  wherein:
 said mode selector comprises a shaft portion pivotally supported by said second handle and having a cross section shaped to provide said cam, and a user operable lever portion for rotating said shaft portion between said first and second mode positions. 
 
     
     
         7 . A dual mode cutting tool according to  claim 2  wherein the mode selector controls the engagement of the pawl linkage with the ratchet teeth by moving a pawl pin of the linkage to an end of the teeth closest to the cutting edge of the blade in the first mode and to an end of the teeth furthest from the cutting edge of the blade in the second mode. 
     
     
         8 . A dual mode ratchet pruner including a first handle having a hand grip and a jaw member, a cutting member pivotally coupled to the first handle intermediate the hand grip and the jaw member, and a second handle pivotally coupled to the first handle, wherein the cutting member has a blade arranged for engagement with the jaw member and a rocker arm formed with a ratchet window having ratchet teeth extending away from the pivot, the dual mode ratchet pruner further including a mode selector operatively supported by the second handle and a pawl linkage coupling the second handle to the ratchet window of the rocker arm, the mode selector acting on the pawl linkage to, in a first mode configuration, bias the pawl linkage toward an end of the ratchet window closest to the blade and, in a second mode configuration, bias the pawl linkage toward an end of the ratchet window furthest from the blade. 
     
     
         9 . A dual mode ratchet pruner according to  claim 8  wherein the mode selector comprises a rotatable cam supported between the walls of the second handle and arranged to bear against the pawl linkage, and a spring acting between the pawl linkage and second handle for biasing the pawl linkage into contact with the cam to thereby move the pawl linkage to the end of the ratchet window furthest from the blade to engage the ratchet teeth when the mode selector is in the second mode configuration. 
     
     
         10 . A dual mode ratchet pruner according to  claim 9  wherein the cam has a flat portion which allows the pawl linkage under bias of the spring to reach the end of the ratchet window closest to the blade when the mode selector is in the first mode configuration. 
     
     
         11 . A dual mode ratchet pruner according to  claim 8  wherein the second handle is pivotally connect to said first handle distant from said blade pivot and the pawl linkage includes a pawl pin that projects through said ratchet window and is arranged to, in the first mode selector configuration, apply force to those of the ratchet teeth nearest the blade pivot and, in the second mode selector configuration, apply force to those ratchet teeth furthest from the blade pivot, when the tool is operated by manipulation of the handle. 
     
     
         12 . A dual mode cutting tool according to  claim 1  wherein the blade and the jaw member in use engage in an anvil-style cutting action. 
     
     
         13 . A dual mode cutting tool according to  claim 1  wherein the blade and the jaw member in use engage in a bypass-style cutting action. 
     
     
         14 . A dual mode ratchet pruner according to  claim 8  wherein the blade and the jaw member in use engage in an anvil-style cutting action. 
     
     
         15 . A dual mode ratchet pruner according to  claim 8  wherein the blade and the jaw member in use engage in a bypass-style cutting action.