Patent ID: 10531928

Abstract:
A robot arm comprising a joint mechanism for articulating one limb of the arm relative to another limb of the arm about two non-parallel rotation axes, the mechanism comprising: an intermediate carrier attached to a first one of the limbs by a first revolute joint having a first rotation axis and to a second one of the limbs by a second revolute joint having a second rotation axis; a first drive gear disposed about the first rotation axis, the first drive gear being fast with the carrier; a second drive gear disposed about the second rotation axis, the second drive gear being fast with the second one of the limbs; a first drive shaft for driving the first drive gear to rotate about the first rotation axis, the first drive shaft extending along the first one of the limbs and having a first shaft gear thereon, the first shaft gear being arranged to engage the first drive gear; a second drive shaft for driving the second drive gear to rotate about the second rotation axis, the second drive shaft extending along the first one of the limbs on a first side of a plane containing the second rotation axis and extending through that plane to the second side of that plane; and an intermediate linkage that meshes with the second drive shaft on the second side of the plane and that couples the second shaft gear to the second drive gear.