Joint mechanism for construction machine

Abstract

A joint mechanism for construction machine includes: a drive unit including an electric motor, the drive unit being capable of outputting torque; a first member including a first coupling wall and a second coupling wall that are aligned in an axial direction along a rotation axis of the torque output by the drive unit; a second member at least partially located between the first coupling wall and the second coupling wall in the axial direction; and a coupling member that couples the first coupling wall and the second member so as to allow relative rotation in a circumferential direction around the rotation axis. The drive unit couples the second coupling wall and the second member so as to allow relative rotation in the circumferential direction.

What is claimed is: 
     
         1 . A joint mechanism for a construction machine, comprising:
 a drive unit including an electric motor, the drive unit being configured to output torque;   a first member including a first coupling wall and a second coupling wall that are aligned in an axial direction along a rotation axis of the torque output by the drive unit;   a second member at least partially located between the first coupling wall and the second coupling wall in the axial direction; and   a coupling member that couples the first coupling wall and the second member so as to allow relative rotation in a circumferential direction around the rotation axis,   wherein the drive unit couples the second coupling wall and the second member so as to allow relative rotation in the circumferential direction.   
     
     
         2 . The joint mechanism of  claim 1 ,
 wherein the second member includes a connecting wall located between the first coupling wall and the second coupling wall in the axial direction,   wherein the coupling member couples the first coupling wall and the connecting wall, and   wherein the drive unit includes a base portion and an output portion, the base portion being fixed to one of the second coupling wall and the connecting wall, the output portion being fixed to another of the second coupling wall and the connecting wall so as to be rotatable in the circumferential direction relative to the base portion.   
     
     
         3 . The joint mechanism of  claim 1 ,
 wherein the second member includes a first connecting wall and a second connecting wall, the first connecting wall being located between the first coupling wall and the second coupling wall in the axial direction, the second connecting wall being located between the first connecting wall and the second coupling wall in the axial direction,   wherein the coupling member couples the first coupling wall and the first connecting wall, and   wherein the drive unit includes a base portion and an output portion, the base portion being fixed to one of the second coupling wall and the second connecting wall, the output portion being fixed to another of the second coupling wall and the second connecting wall so as to be rotatable in the circumferential direction relative to the base portion.   
     
     
         4 . The joint mechanism of  claim 3 , wherein the base portion is located between the first connecting wall and the second connecting wall in the axial direction. 
     
     
         5 . The joint mechanism of  claim 4 ,
 wherein the second member includes a third connecting wall located opposite the first connecting wall with respect to the second connecting wall in the axial direction, and   wherein the drive unit extends through the third connecting wall.   
     
     
         6 . The joint mechanism of  claim 2 , wherein the first member is a bucket with an opening. 
     
     
         7 . The joint mechanism of  claim 1 ,
 wherein the second member includes a first connecting wall and a second connecting wall, the first connecting wall being located between the first coupling wall and the second coupling wall in the axial direction, the second connecting wall being located opposite the first connecting wall with respect to the second coupling wall in the axial direction,   wherein the coupling member is a first coupling member, the first coupling member coupling the first coupling wall and the first connecting wall,   wherein the joint mechanism further comprises a second coupling member that couples the second connecting wall and the second coupling wall so as to allow relative rotation in the circumferential direction, and   wherein the drive unit includes a base portion and an output portion, the base portion being fixed to one of the second coupling wall and the first connecting wall, the output portion being fixed to another of the second coupling wall and the first connecting wall so as to be rotatable in the circumferential direction relative to the base portion.   
     
     
         8 . The joint mechanism of  claim 1 ,
 wherein the drive unit includes a base portion and an output portion, the base portion being fixed to one of the second coupling wall and the second member, the output portion being fixed to another of the second coupling wall and the second member so as to be rotatable in the circumferential direction relative to the base portion, and   wherein the output portion has a spline groove formed along the rotation axis, and the output portion is fixed to the second coupling wall or the second member via the spline groove.   
     
     
         9 . A joint mechanism for a construction machine, comprising:
 a drive unit including an electric motor, the drive unit being configured to output torque;   a first member; and   a second member aligned with the first member in an axial direction along a rotation axis of the torque output by the drive unit,   wherein the drive unit includes a base portion and an output portion, the base portion being fixed to the second member, the output portion being fixed to the first member so as to be rotatable in a circumferential direction around the rotation axis relative to the base portion, and   wherein the output portion has a spline groove formed along the rotation axis, and the output portion is fixed to the first member via the spline groove.