US 7,614,842 B2
Lift arm assembly with integrated cylinder stop
Shawn Ellefson, Bismarck, N. Dak. (US); and Warren Schatz, Mandan, N. Dak. (US)
Assigned to Clark Equipment Company, West Fargo, N. Dak. (US)
Filed on Feb. 27, 2007, as Appl. No. 11/679,621.
Prior Publication US 2008/0203372 A1, Aug. 28, 2008
Int. Cl. E02F 3/80 (2006.01)
U.S. Cl. 414—680  [298/17 R; 298/22 R] 18 Claims
OG exemplary drawing
 
1. A hydraulic lift arm assembly comprising:
a lift arm movable between raised and lowered positions;
a lift cylinder having a cylinder body and an extensible rod, one of the cylinder body and extensible rod being coupled to the lift arm such that extension and retraction of the extensible rod with respect to the cylinder body moves the lift arm toward the raised and lowered positions, respectively;
a lift arm stop coupled to the lift arm, and movable while coupled to the lift arm between a stowed position in which the stop is detachably coupled to the lift arm and a locked position in which the stop resists substantial retraction of the extensible rod with respect to the cylinder body and thereby resists substantial lowering of the lift arm from the raised position, one of the stop and lift arm including a slot, and the other of the stop and lift arm including a pin within the slot to linearly and pivotably couple the stop to the lift arm and to permit pivotal and linear movement of the stop with respect to the lift arm, the stop including at least one tongue extending from an engaging end of the stop, the stop and lift arm being so disposed and arranged such that linear movement of the stop in a first direction with respect to the lift arm moves the pin linearly within the slot and thereby creates a gap between the engaging end of the stop and a portion of the cylinder body, the gap providing sufficient clearance for the at least one tongue to pivot past the portion of the cylinder body as the stop moves toward the locked position, the stop and lift arm being so disposed and arranged such that linear movement of the stop in a second direction opposite the first direction moves the pin linearly within the slot in the opposite direction and thereby positions the stop in the locked position in which the engaging end of the stop engages the portion of the cylinder body and the at least one tongue engages a back side of the cylinder body, engagement of the at least one tongue against the back side of the cylinder body resists pivotal movement of the stop out of the locked position; and
a stowing mechanism automatically detachably coupling the stop to the lift arm in response to the stop being moved into the stowed position.