GB1513238A - Planters - Google Patents

Abstract

1513238 Planters MASSEY-FERGUSONPERKINS Ltd 7 Aug 1975 [17 Aug 1974] 36303/74 Heading AID A planter 10 comprises a seed hopper 16, coulters arranged in forward and rearward assemblies 22, 23 each having a slit opening disc 30 and a pair of slit widening discs 32 seed feeding and metering means 18, 20 feeding seed via the tubes 21 to the furrow opened by the coulter, and a fluid pressure operated thrust device, a hydraulic accumulator being in fluid pressure communication with the thrust device. Each assembly 22, 23 is supported on arms 24, 29 respectively which are pivoted at 26 to the frame (28-Fig. 2, not shown) of the machine, the assemblies being urged upwardly by springs 42. Singleacting hydraulic rams 31, 33 urge the assemblies into contact with the ground and are connected via hoses 35, a space within a box beam 34 and metal conduit 36 to a hydropneumatic accumulator 38 and a pressurising device 40. The accumulator comprises a synthetic rubber bladder 46 containing nitrogen under pressure located within a steel shell 47. In use, fluid is supplied to the device 40 moving a piston 60 until the piston rod 67 engages an adjustable stop 70. As the coulters traverse undulating ground the accumulator 38 operates to supply or receive hydraulic fluid due to the presence of the bladder 46 thus maintaining constant pressure in the rams 31, 33. The capacity of the accumulator, or the sum of the capacities of a series of accumulators connected in parallel, should be at least 15 times and preferably at least 100 times the displacement volume of each of the sums 31, 33 when the pistons 52 thereof retract between maximum and minimum coulter penetration of the soil.