Abstract: Openers for a seeder, configured to be adjustably engaged with a soil surface when in use; each opener having compliance to vertical and lateral excessive forces independently applied to soil-engaging parts: a fertiliser tine, a seed tine, a press wheel, a coulter, and a support wheel. The openers share a hydraulic circuit, linked to each internal frame-lifting ram so that localised rise and fall effects arising from soil surface irregularities are shared, maintaining a mean height. The seed tine of each opener is mechanically coupled to the preceding fertilizer tine and is lifted when the fertilizer tine is displaced. The openers do not require external weight support.

Abstract: An agricultural machine has a symmetrical chassis hydraulically transformable between a folded transport configuration and two unfolded configurations, using articulated beams. An air seeder example has a primary beam linking a tractor to a hopper-carrying trailer, also locating the chassis. Machinery such as seed openers is held in frames pivoted from the tertiary beams. In all configurations except completely folded, lateral chains that are maintained tight with a hydraulically powered tensioning system having sideways compliance maintain the tertiary beams and frame-supported machinery in a symmetrical configuration to each side of the primary beam, when working.

Abstract: Wheat or other granular, flowable material is supplied from a metering hopper at a controlled rate through a limiting aperture at a base of a hopper side wall. A moving surface which has served as a floor of the hopper emerges through the aperture, carrying a covering of material out and toward a material disposal area and is then recirculated into the hopper. The moving surface is a repeatedly used upper surface of a disc or cone that is rotated by a motor. Supply of material is immediately varied by varying the speed of the moving surface.

Abstract: Openers for a seeder, configured to be adjustably engaged with a soil surface when in use; each opener having compliance to vertical and lateral excessive forces independently applied to soil-engaging parts: a fertiliser tine, a seed tine, a press wheel, a coulter, and a support wheel. The openers share a hydraulic circuit, linked to each internal frame-lifting ram so that localised rise and fall effects arising from soil surface irregularities are shared, maintaining a mean height. The seed tine of each opener is made liftable immediately the preceding fertiliser tine is displaced. The openers do not require external weight support.