(under subclass 149) Apparatus including means permitting the furrow opening element to shift with respect to the soil or with respect to its supporting or propelling means when it meets an obstacle while being drawn over the field, said means (1) having a high initial resistance to said shifting of the element, which resistance decreases after the element starts to shift, or (2) requiring manual resetting by an attendant (e.g., shear pin).
(1) Note. This definition comprehends flat bottomed structures or structures which have a bottom which is V-shaped in cross-section.
SEE OR SEARCH CLASS
172, Earth Working,
260.5, 261+, and 705 for trip mechanisms for earth-working elements used without material depositors.
