Patent ID: 9739030
Date: 2017-08-22
CPC Classifications: E02F

Claim:
1. A hydraulic excavator comprising: an undercarriage frame supported by a left continuous track trained around a left front idler roller and a left rear driven sprocket and supported by a right continuous track trained around a right front idler roller and a right rear driven sprocket; an upper frame assembly rotatably attached to the undercarriage frame for pivotal movement about a vertical axis and including a counter weight attached to a rear portion of the upper frame assembly, an operator's enclosure mounted on a forward portion of the upper frame assembly, a housing mounted on the upper frame assembly between the counter weight and the operator's enclosure; a boom assembly including a left boom member with a left rear portion including, a left rear end pivotally attached to the upper frame assembly by a left boom pin a left front portion with a left free end and a left transition portion integral with the left rear portion and the left front portion, a right boom member with a right rear portion including a right rear end pivotally attached to the upper frame assembly by a right boom pin, a right front portion with a right free end and a right transition portion integral with the right rear portion and the right front portion and wherein the left transition portion off sets the left front portion to the right of the left rear portion and the right transition portion offsets the right front portion to the left of the right rear portion, the left boom pin and the right boom pin are both coaxial with a boom horizontal axis, positioned near the vertical axis, the left front portion parallel to the right front portion, the left rear portion positioned to the left of the operator's enclosure, and the right rear portion positioned to the right of the operator's enclosure; a stick assembly including an elongated stick portion with a stick distal end and a stick proximal end, a transverse tube fixed to the stick proximal end, the transverse tube coaxial with a stick pivot axis a left stick tine fixed to the transverse tube adjacent to a left tube end, a right stick tine fixed to the transverse tube adjacent to a right tube end and parallel to the left stick tine; a left trunnion including a left central trunnion passage extending from a left trunnion outside end surface to a left trunnion inside end surface, a left trunnion end flange including a left cylindrical radially outer surface extending axially relative to the left central trunnion passage from the left trunnion outside end surface to a left radially extending boom retainer surface, a left cylindrical bearing surface extending from the left trunnion end flange toward the left trunnion inside end surface and to a left radially extending ring shaped surface, a left male trunnion spline extending axially between the left radially extending ring shaped surface and the left trunnion inside end surface; a right trunnion including a right central trunnion passage extending from a right trunnion outside end surface to a right trunnion inside end surface, a right trunnion end flange including a right cylindrical radially outer surface extending axially relative to the right central trunnion passage from the right trunnion outside end surface to a right radially extending boom retainer surface, a right cylindrical bearing surface extending from the right trunnion end flange toward the right trunnion inside end surface and to a right radially extending ring shaped surface, a right male trunnion spline extending axially between the right radially extending ring shaped surface and the right trunnion inside end surface; a stick shaft with a left end and a right end, a shaft diameter that is substantially the same as a diameter of the left central trunnion passage in the left trunnion and the right central trunnion passage in the right trunnion, a plurality of left threaded bores in the left end, a plurality of right threaded bores in the right end, at least two left side recesses adjacent to the left end, at least two right side recesses adjacent to the right end and extending through the transverse tube; a left boom bore receiving the left cylindrical bearing surface of the left trunnion, the left central trunnion passage of the left trunnion receiving the left end of the stick shaft and at least two left trunnion keys engage the at least two left side recesses; a right boom bore receiving the right cylindrical bearing surface of the right trunnion, the right central trunnion passage of the right trunnion receiving the right end of the stick shaft and at least two right trunnion keys engage the at least two right side recesses; a left retainer plate clamped to the left end of the stick shaft by at least two left bolts and a right retainer plate clamped to the right end of the stick shaft by at least two right retainer bolts that cooperate to hold the left male trunnion spline in engagement with a tube left female spline, to hold the left trunnion radially extending ring shaped surface in engagement with the left tube end, to hold the right male trunnion spline in engagement with a tube right female spline, and to hold the right trunnion radially extending ring shaped surface in engagement with the right tube end; a left hydraulic boom cylinder includes a left cylinder end pivotally attached to the upper frame assembly and rod end pivotally connected to the left boom member, and a right hydraulic boom cylinder includes a right cylinder end pivotally attached to the upper frame assembly and a rod end pivotally connected to the right boom member and wherein both cylinders pivot the left boom member and the right boom member together about the boom horizontal axis; a left hydraulic stick actuator includes a left stick cylinder end pivotally attached to the left boom member and a left stick rod end pivotally attached to the left stick tine, and a right hydraulic stick actuator includes a right stick cylinder end pivotally attached to the right boom member and a right stick rod end pivotally attached to the right stick tine, and wherein the left hydraulic stick actuator and the right hydraulic stick actuator both pivot the stick together about a stick pivot axis; a bucket assembly pivotally attached to the distal end of the stick assembly by a bucket pivot pin; and a hydraulic cylinder including a cylinder end pivotally attached to the elongated stick portion by a pivot pin, and a rod connected to the bucket assembly through a linkage assembly.