Agricultural boom with a retractable tip portion

A boom for mounting on a tractor for use in spreading a fluid material across the ground as the tractor transports the boom across the ground, the boom comprising:

• a main generally horizontal boom section having an inner end mounted on the tractor and an outer end spaced outwardly from the tractor to one side thereof;
• a break-away tip portion mounted on the outer end of the main boom section;
• the tip portion having an inner end pivotally mounted on the outer end of the main section for pivotal movement about an axis which is generally upright, such that the tip portion, on impacting an obstacle, pivots about the axis from a working position collinear with the main section to a retracted position inclined rearwardly from the main section;
• the main body section including an inner boom portion and an outer boom portion, the outer boom portion being mounted at an outer end of the inner boom portion;
• the inner boom portion being mounted on the tractor for folding movement between an extended working position and a folded retracted position;
• the outer boom portion being mounted on the inner boom portion for folding movement relative to the inner boom portion about a folding axis which is transverse to the boom and which is generally horizontal through an angle of the order of 180.degree. between an extended position in which the outer portion is collinear with the inner portion and a folded position in which the outer portion overlies the inner portion;
• and means for actuating movement of the tip portion to the retracted position for at least part of the folding movement of the outer boom portion, for reducing a maximum height of an outer end of the tip portion during said folding movement.

A boom for mounting on a tractor for use in spreading a fluid material across the ground as the tractor transports the boom across the ground, the boom comprising:

• a generally horizontal main boom section having an inner end mounted on the tractor and an outer end and being movable from a deployed position in which the outer end extends outwardly to one side of the tractor to a folded position in which the outer end is retracted toward the tractor;
• a break-away tip portion mounted on the outer end of the main boom section for movement therewith from the deployed position to the folded position;
• the tip portion having an inner end pivotally mounted on the outer end of the main section for pivotal movement about a tip pivot axis which is generally upright, such that the tip portion is pivotal about the tip pivot axis from a working position collinear with the main section to a retracted position inclined rearwardly from the main section;
• a protection cable mounted on the tip portion so as to extend generally parallel to the tip portion forwardly of the tip portion for impacting an obstacle in advance of the tip portion and arranged such that impact with an obstacle causes a deflection of the cable toward the tip portion;
• a cushion arm connected to the cable;
• a spring coupling connected to the cushion arm so as to absorb energy from the impact;
• the cushion arm and the spring coupling being arranged so as to cause transmission of force from the impact through the cushion arm to the tip portion in a direction to accelerate the tip portion in pivotal movement relative to the main boom section about said axis rearwardly away from the obstacle.

A boom for mounting on a tractor for use in spreading a fluid material across the ground as the tractor transports the boom across the ground, the boom comprising:

• a generally horizontal main boom section having an inner end mounted on the tractor and an outer end and being movable from a deployed position in which the outer end extends outwardly to one side of the tractor to a folded position in which the outer end is retracted toward the tractor;
• a break-away tip portion mounted on the outer end of the main boom section for movement therewith from the deployed position to the folded position;
• the tip portion having an inner end pivotally mounted on the outer end of the main section for pivotal movement about a tip pivot axis which is generally upright, such that the tip portion is pivotal about the tip pivot axis from a working position collinear with the main section to a retracted position inclined rearwardly from the main section;
• a protection cable mounted on the tip portion so as to extend generally parallel to the tip portion forwardly of the tip portion for impacting an obstacle in advance of the tip portion and arranged such that impact with an obstacle causes a deflection of the cable toward the tip portion;
• a cushion arm connected to the cable which comprises a lever attached to the tip portion and extending forwardly therefrom such that distortion of the cable pulls a forward end of the lever to apply a force to the tip portion in a direction to move rearwardly around the tip pivot axis.