Patent ID: 7971375

Claim:
A tooth system intended for a tool of an earth moving machine, which tooth system is of the type comprising a holder attached to the tool and a front tooth portion, which is detachably arranged in relation to and on the holder and is in the form of an exchangeable wear part, replacement part, or both intended for the actual earth moving, which tooth portion comprises a rear leg and the holder comprises a cavity designed to receive the leg during interaction with the tooth portion and, thus, achieve a common joint for the absorption of arising forces through a predetermined connection geometry comprising special, opposed, mutually interacting contact surfaces and, at least initially, clearance surfaces that are arranged along the tooth portion and holder, wherein the tooth leg and cavity, along at least a front part of said joint have a multi-armed cross section comprising projection arms, and grooves each interacting with a projection arm and wherein a tensioning device is arranged at the cavity's rear part for achieving a tightening and adjustable pretensioning of the tooth portion in relation to the holder essentially axially along the cavity's longitudinal symmetry axis Y, wherein the projection arms comprise at least one essentially vertically arranged arm or heel and two, theretoward essentially lateral, wing portions, and wherein contact zones for transverse force absorption, as well as that of torques resultant therefrom, depending on a given force's direction of impact, are arranged along at least an essentially vertical, lengthwise contact surface at the torque heel, at least one upper, inclined, lengthwise contact surface at the top side of the tooth leg, at least one lower, essentially horizontal, lateral contact surface at one of the tooth portion's lateral wing portions, at least one upper, inclined contact surface at the tooth portion's other lateral wing portion and at least one upper, essentially horizontal, lateral contact surface at the tooth portion's other lateral wing portion; or, for a force from the opposite direction, essentially through the corresponding contact surfaces.