Trip mechanism for ground working implement

Claim 1

A tillage implement comprising: a frame; a ground working tool; means mounting said tool on said frame for movement away from an operating ground penetrating position toward a fully elevated position above the ground, said mounting means guiding said tool during movement between said positions; said mounting and guiding means including linkage means in the form of a single link pivotally connected at one end to said frame and pivotally connected at the other end to said tool, and a slotted cam surface in said frame with a follower means on said tool engaging said cam surface, said tool having an abutment thereon defined by a pin extending transversely of the tool adjacent the forward end thereof and spaced from said follower means; latch means releasably retaining said ground working tool in said ground penetrating position, said latch means including a latch member having its midportion pivotally mounted on said frame forwardly of said tool, said latch member having a detent surface formed by an upwardly facing notch in a portion of the latch member rearwardly of its pivot axis, said notch being engageable with said pin; and resilient means defined by a generally vertically disposed compression spring bearing against the upper surface of a portion of the latch member forwardly of its pivot axis for releasably biasing said latch means into retentive engagement with said pin.