Feed control device for agricultural harvesting machines, for example, grain harvesters

1,141,961. Combine harvesters. VSESOJUZNY NAUCHNO - ISSLEDOVATELSKY I N S T I T U T SELSKOKHOZYAISTVENNOGO MASHINOSTROENIA. 1 Feb., 1966, No. 4367/66. Heading A1F. [Also in Division G3] A control device, for automatically adjusting the ground speed of a harvesting machine, e.g. a combine, in dependence on the volume of material fed into the machine and the rate-of handling of the material in the machine, e.g. by a threshing mechanism, comprises a unit for sensing the volume of material gathered, a rate-of-treatment control unit, and a slide valve controlled by the volume sensing unit, which valve controls the operation of an hydraulic cylinder connected to a variable speed gear through which motion is adapted to be imparted to the driving wheels of the machine. The device further includes an automatic adjustment means comprising an actuating mechanism controlled by the rate-of-treatment control unit and operatively connected to the slide valve or the volume sensing unit, and a timing device ensuring the required duration of operation of the actuating mechanism. As illustrated the volume sensing unit is an arm 17 positioned e.g. in the crop elevator and connected to the piston 12 of the slide valve, which controls via hydraulic cylinder 6 the variable speed gear 7. When the volume of material being threshed rises above or falls below a predetermined value a governor 2 which comprises the rate-oftreatment control unit causes one of the contacts 18, 19 to close and actuate a reversible electric motor 8 in one sense or the other. The motor is connected by reduction gearing 14 and a shaft 15 having a screw thread which engages a screw thread in a housing to a sleeve 16 on the slide valve. Operation of the motor effects displacement of the sleeve and consequently causes the setting of the arm 17 to be varied. Each operation of the motor is limited by a timing device 9. In an alternative embodiment (Fig. 2, not shown) the sensing arm causes actuation of the piston of a slide valve by electro-magnetic means. The motor is replaced by a step-by-step selector and the timing device is constituted by an arrangement of relays and capacitors.