Patent ID: 8662216

Claim:
An undercarriage for an excavator having a frame with first and second sides, comprising: a first track assembly configured to be positioned on the first side of the frame and including a first track and a drive track unit for driving movement of the first track, the first track assembly having: an inner portion, an outer portion, and a middle portion between the inner portion and the outer portion; a first flange and a second flange spaced apart from the first flange, the first and second flanges extending from the inner portion to the outer portion and defining a gap therebetween; and a pin extending across the gap from the first flange to the second flange; a second track assembly configured to be positioned on the second side of the frame and including a second track and a drive track unit for driving movement of the second track, the second track assembly having an inner portion, an outer portion, and a middle portion between the inner portion and the outer portion, the second track assembly being spaced apart from first track assembly along a first axis; and an adjustment mechanism coupled to the first track assembly and to the second track assembly, wherein the adjustment mechanism is pivotably coupled to the pin of the first track assembly, the adjustment mechanism being capable of extending and retracting along an axis parallel to the first axis to increase and decrease the spacing between the first track assembly and the second track assembly along the first axis, wherein the adjustment mechanism comprises a double-acting hydraulic cylinder, the double-acting hydraulic cylinder being pivotally coupled to both the middle portion of the first track assembly and the middle portion of the second track assembly; a first elongate member coupled to the first track assembly and extending toward the second track assembly parallel to the first axis; and a first channel configured to be coupled to the frame and to extend toward the first track assembly, the first elongate member being slidably received in the first channel, the first channel restraining sliding movement of the first elongate member to the first axis.