GB1228709A - - Google Patents

Abstract

1,228,709. Plough landing device. DEERE & CO. 29 May, 1969 [29 May, 1968], No. 27340/69. Heading A1B. [Also in Division G3] A semi-mounted multi-furrow plough 10 has an automatic landing device 70 to ensure that the plough bodies 42 are accurately positioned adjacent the furrow wall 64. The landing device 70 comprises a depending arm 76 rotatably mounted, about pin 134, on a member 130 which is attached to the link 118 which is in turn pivotally attached to the link 116 by means of the pin 100. The arm 118 is connected to a three-position hydraulic slide valve 72 by means of a spring strap 146. A clock spring 140 biasses the member 130 and the arm 76 in a clockwise sense (as seen in Fig. 1) and a stop 144 is provided to limit any clockwise movement. The arm 116 is pivotally mounted on a securing, bracket by a pin (122), Fig. 2 (not shown), which is substantially parallel to the pin 100. A tension spring 78 biasses the arms 116, 118 towards the furrow wall. The piston rod of a double acting hydraulic jack is attached to the tractor linkage and the plough frame is attached to the jack cylinder. Pressure fluid is supplied to the jack via the three position valve 72. In operation: The plough is caused to be lowered into work by raising the rear wheel 50 and lowering the draught links 12. Should the arm -contact unploughed ground the arm 116 will swing upwardly about its pivot (122), Fig. 2 (not shown), and the arm 76 will swing about pin 134 due to the forward motion of the plough. The angled portion 162 of the arm will then be in contact with the ground and the forward motion will tend to cause the arm 76 to swing outwardly about the pin 100 until the portion 156 drops into the furrow. The pivoting of the arm 76 and 118 about the pin 100 operates the valve 72 through the strap 146 and causes the cylinder 23 to move the plough nearer the furrow until the desired position is reached, i.e. the position in which the valve 72 is held in neutral. The desired spacing is achieved by suitable adjustment of the length of link 82. Any deviation of the plough frame 30 from the desired position is automatically cancelled by the valve 72 and jack 23. The rear wheel 50 is steered by the arm 54 and the crank 56 on the pivot shaft 26.