04210209 is referenced by 6 patents and cites 13 patents.

An implement is connectable to the lifting hitch of a tractor and at least one rotary tool is driven to rotate about an upwardly extending axis. The tool or a trestle frame has an overload connection that allows the tool or frame to pivot to an inoperative position upon overload. The tool can be a blade on a carrier part that is pivoted to a support part on a spoke and a shear pin interconnected to prevent such pivoting unless tripped by overload. The parts can have a discharge arrangement that ejects the sheared pin portion from a recess in one part. Upon adjustment of the tool, the pin remainder can effect reconnection. In another embodiment, the trestle frame is coupled to a three point hitch and the implement can be tripped through a pivot connection, including a strut made up of two shaft parts, one of which holds a shear pin and the other receives a pin portion near the junction of the parts. The pin element normally prevents relative pivoting of the implement relative to the tractor connection. Upon overload the strut jack-knifes to allow the entire implement to pivot relative to the trestle.

Title
Agricultural implement
Application Number
5/880091
Publication Number
4210209
Application Date
February 22, 1978
Publication Date
July 1, 1980
Inventor
Cornelis van der Lely
7, Bruschenrain, Zug
CH
Agent
Mason Mason and Albright
IPC
A01B 61/04
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