Wear assembly for a bucket of an extraction or works machine

Abstract

Wear assembly, including a tooth holder and a tooth for a bucket, and also a sheath, with a housing duct, the sheath being received in the tooth holder. Also provided is a key which is received in the housing duct by pivoting between an insertion orientation, so as to be slid into the housing duct, and a locking orientation, so as to clamp the tooth against the tooth holder by the key bearing against the tooth and the sheath bearing against the tooth holder under the action of the key, in opposite directions. In order to facilitate manufacture without prejudicing reliability, the key is monolithic and includes both a bearing cam, for bearing against the tooth holder, and a bearing end, for bearing against the tooth.

1 . A wear assembly for a bucket of an extraction or work machine, the wear assembly comprising:
 a tooth holder, attached to the bucket and comprising a keyway, traversed by a keyway axis;   a tooth, nested onto said tooth holder along a nesting direction, and comprising a bearing seat; and   a keying device, comprising:
 a sheath, comprising:
 a housing duct duct; and 
 an outer wall, the sheath being configured to be received in said keyway by means of the outer wall, the sheath thereby being fixed in rotation relative to said tooth holder about the keyway axis by means of the outer wall; and 
 
 a key, which is monolithic and comprises a bearing cam and a bearing end formed in one piece, the key being received in said housing duct so as to be pivotable relative to said sheath, between:
 an insertion orientation, wherein the key is able to be slid into said housing duct while said sheath is received in, said keyway; and 
 a locking orientation, wherein, while said sheath is received in the keyway said keyway, the keying device clamps said tooth against said tooth holder along the nesting direction under the action of said key, by bearing of said bearing end directly against said bearing seat, along the nesting direction, and by bearing of said bearing cam against said housing duct, in the opposite direction to the nesting direction. 
 
   
     
     
         2 . The wear assembly according to  claim 1 , wherein:
 said sheath is monolithic, said outer wall and said housing duct being formed in one piece; and   bearing of said bearing cam against said housing duct is achieved without any intermediate part between said key and said sheath.   
     
     
         3 . The wear assembly according to  claim 1 , wherein:
 the said bearing seat comprises two primary faces, each primary face being obliquely oriented, being turned toward the other primary face and in the opposite direction to the nesting direction; and   said bearing end comprises two secondary faces, said bearing end bearing against said bearing seat in that said bearing end is received between said primary faces, with each secondary face bearing against one of said primary faces.   
     
     
         4 . The wear assembly according to  claim 1 , wherein:
 said tooth comprises a retaining rib; and   said key comprises two radial shoulders, which are formed in one piece with said bearing end and which, when said key is received in said housing duct and the sheath ( 5 ) said sheath is received in said keyway:
 capture said retaining rib between them, parallel to the keyway axis, when said key is in the locking orientation, to immobilize said key relative to said tooth parallel to the keyway axis, and 
 disengage from said retaining rib when the key said key is in the insertion orientation. 
   
     
     
         5 . The wear assembly according to  claim 1 , wherein said key and said tooth comprise rotational stops, which come into rotational stop when said key is in the insertion orientation, to limit pivoting of said key to the insertion orientation and which comes into a rotational stop when said key is in the locking orientation to limit pivoting of said key to the locking orientation. 
     
     
         6 . The wear assembly according to  claim 1 , wherein:
 said key comprises a dismantling groove, which is provided along said bearing end; and   when said sheath is received in keyway and said key is received in said housing duct, said dismantling groove is:
 disengaged from said bearing seat, when said key is in the insertion orientation, so that said key may be extracted from said housing duct by inserting a dismantling tool into said dismantling groove, and 
 turned against said bearing seat ( 21 ), when said key is in the locking orientation. 
   
     
     
         7 . The wear assembly according to  claim 1 , wherein said key defines a parting line plane, which traverses said bearing cam and said bearing end, said bearing cam and said bearing end being tapered on either side of the parting line. 
     
     
         8 . The wear assembly according to  claim 7 , wherein:
 said key comprises an actuator head, configured to be coupled with an actuator tool, to actuate said key by pivoting between the insertion orientation and the locking orientation, the actuator head being formed in one piece with said bearing cam and said bearing end and protruding out of said sheath when said key is received in said housing duct; and   said actuator head is tapered on either side of the parting line.   
     
     
         9 . The wear assembly according to  claim 8 , wherein, to be coupled with the actuator tool, said actuator head comprises an actuation notch and two fingers, which are arranged on either side of the actuation notch ( 89 ) to delimit the actuation notch, the actuation notch and the two fingers being traversed by the parting line and being tapered on either side of the parting line. 
     
     
         10 . The wear assembly according to  claim 1 , wherein:
 said tooth comprises a keyhole, into which said keyway opens when said tooth is received on said tooth holder, said bearing seat being formed on an edge of said keyway; and   the wear assembly further comprises a plug, which is configured to said keyhole by covering said keying device while said sheath is received in said keyway and said key is received in said housing duct in the locking orientation. Please add the following new claim.   
     
     
         11 . The wear assembly according to  claim 2 , wherein said housing duct is coated with a lubricant.