Control arrangement for an implement draft tongue

#The invention concerns a control arrangement for a draft tongue of a towed implement, and more particularly relates to a powered arrangement for moving the draft tongue between first, working positions and a second position, wherein the draft tongue extends transverse to the direction of operation of the implement.

#U.S. Pat. No. 3,919,831 discloses a towed mowing implement with a draft tongue that can be repositioned between operating positions and a transport position by means of a hydraulic cylinder, where the tongue extends transverse to the direction of operation of the mowing implement in the transport position. In the transport position, the mowing implement can be towed on a trailer behind an agricultural tractor or the like. The repositioning movement of the hydraulic cylinder is transmitted by a scissors-like linkage, where the hydraulic cylinder is retracted in the transport position. The effect of the hydraulic motor is controlled jointly by two hydraulic cylinders so that with the full stroke of the hydraulic cylinder once the tongue reaches its transport position and the other time it does not.

#U.S. Pat. No. 4,558,560 also discloses a control arrangement, that includes a hydraulic cylinder, for the pivoting of a draft tongue of a mowing implement into a transport position. The hydraulic cylinder operates upon the end of the tongue and is limited in its stroke during the operation by mechanical stops of a plate between the tongue and a frame of the mowing implement. In order to be able to completely retract the pressurized fluid motor and thereby to pivot the tongue into a transport position, the plate with the stops is pivoted into a further position.

#FIG. 1 is a schematic top plan view of a train consisting of a towing vehicle and a towed implement.

#FIG. 2 is a diagram of the hydraulic circuit for controlling an extensible and retractable hydraulic actuator for swinging the draft tongue of the implement.

#FIG. 3 is a perspective view of the hydraulic actuator shown in its retracted condition.

#Referring now to FIG. 1, there is shown a towed implement 10 and a towing vehicle 12. The implement 10 is configured as a mowing implement, but may, however, be a ground breaking implement, a harvesting implement, a plant processing implement, or any other towed implement.

#The implement 10 includes a frame 14 and wheels 16 that support it on the ground and carry a front attached crop mowing and windrowing arrangement 18. A bearing 20 is provided at a center location between opposite ends of the frame 14 and couples a rear end of a draft tongue 22 for swinging transversely thereabout, the forward end of the draft tongue 22 being coupled over a bearing 24 and draft coupler 26 to a draft hitch arrangement 28 of the towing vehicle 12. The relative position of the draft tongue 22 to the frame 14 is controlled by an extensible and retractable hydraulic actuator 30, whose actuation is performed by a control arrangement 32, shown in FIG. 2.

#The control arrangement 32 includes a fluid reservoir 34, a pump 36, a pressure relief valve 38, a direction control valve 40, an interrupter valve 54, an actuating device 42, a switching device 44 and a deactivating element 46. The control arrangement 32 is located partially on the implement 10 and partially on the towing vehicle 12, where the deactivating element 46 leads to the towing vehicle in the vicinity of the operator.