Abstract: A drive system is provided for driving a rotatable seed drum of a seed planter which includes a fan for supplying air under pressure to the drum. The drum drive system includes an alternator which is mechanically driven, preferably from a drive for the planter fan, and which has output terminals connected to a motor mechanically connected to the seed drum. A ground speed signal generator is mechanically connected to a ground-engaging wheel to develop a signal which has an amplitude proportional to ground speed and which is applied through an adjustable resistance to a field winding of the alternator after passing through a control box. A drum speed signal generator arrangement is provided for developing a drum speed signal having an amplitude inversely proportional to the speed of rotation of the seed drum. This signal is also directed to the control box. Preferably, the signal generators include reluctance generator devices.

Abstract: An implement that includes a pair of furrow forming disks, a seed tube located between the disks for depositing seed in the furrow, a seed firming wheel rotatably supported between the disks for movement in the furrow generally adjacent the tube exit and a pair of pivotally mounted furrow closing and gauge wheels located generally adjacent the seed firming wheel. The elements of the implement are particularly constructed and arranged primarily to achieve accurate seed depth control.

Abstract: An electrical vehicle is propelled by a constant speed motor receiving current from a storage battery. An alternator, driven by the vehicle power train through a differential while the vehicle is in motion, is associated with the drive train such that it controls the velocity of the vehicle. Dynamic braking through increasing field current of the alternator is provided. The alternator is used to recharge the storage battery during periods of less than maximum vehicle velocity and also during deceleration of the vehicle.

Abstract: A control system is provided for a plow including forward and rearward hingedly connected frame sections each carrying a plurality of plow bottoms and forward, intermediate and rearward linkage assemblies each including a hydraulic actuating cylinder, supporting the forward end of the forward frame section, the junction between the frame sections and the rearward end of the rearward section. The control system includes electrical circuitry which controls solenoid-actuated valves of a hydraulic system with separate portions of the circuitry being operable for controlling the respective linkage assemblies but with an operation such that only one hydraulic cylinder is operable at any one time to minimize load requirements. In a raising operation, the forward and intermediate linkage assemblies are sequentially operated. Another feature is a draft control arrangement which includes a dither circuit operative to alternately adjust the forward and intermediate linkage assemblies.

Abstract: A valve assembly is provided in which a first poppet member and at least one subsequent poppet member each having a valve face engageable with a valve seat between first and second passages. A first and a subsequent pilot valve is operative for selectively establishing communication between a fluid reservoir and a space at one side of a piston portion of each poppet member and a pair of restricted flow passages are provided in each poppet member between such space and the first and second passages, such restricted flow passages being preferably formed in the poppet members with ball check valves provided therein. Such restricted flow passages operate upon closure of the pilot valve to develop a static pressure in the space corresponding to the pressure in the one of the first and second passage which has the higher pressure therein so as to move the poppet member to and hold it in its closed position in response to pressures applied from either of the first and second passages.

Abstract: Force-measuring devices are provided for measuring the force transmitted between two members, including a force-transmitting element of resiliently deformable material and of generally C-shaped cross-sectional configuration having inner and outer generally cylindrical and concentric surfaces and an axially extending slot defined by facing angularly spaced surfaces. The outer cylindrical surface is engagable by the members at diametrically opposite portions of the element which lie along a diametral plane generally transverse to a radial plane through the slot with the diametrically opposite portions being relatively displaced toward each other in proportion to the force transmitted between the members. Such displacement is measured by a potentiometer having an arm rotated through a lever member from displacement of one of the diametrically opposite portions relative to the other.

Abstract: A normally closed solenoid valve operates conjunctively with a two position pilot valve to limit the amount of engine braking through the drive train of a vehicle by reducing the drive relief valve setting in the disengaged side of a hydrostatic transmission. A second normally closed solenoid valve operates a second two position pilot valve to modulate the rate that the forward drive relief valve in the engaged side of the transmission hydrostatic drive loop permits drive pressure to build up as the vehicle is started in motion. An electrical switch on the transmission control rod initiates activation of the normally closed solenoid valves when the vehicle operator selects a direction of travel.