Abstract: A detent hold and release mechanism on a manually positioned valve controller which electrically signals a servo controlled conventional hydraulic control valve. The mechanism has a detented operating position and a spring-returned neutral position when the detent is released; the detent is held in operating position by a locking pawl urged by a permanent magnet. The mechanism is released by energizing an electro-magnet positioned adjacent the permanent magnet with reverse polarity whereby the combined magnet forces are neutralized, thereby releasing the pawl and allowing the valve controller to return to the neutral position.

Abstract: A normally closed spool type solenoid-controlled valve which changes its opening in proportion to the amount of current supplied to the solenoid. The spool which blocks the valve opening in an overlapping relation is held in a closed position by a dual spring design having differing spring rates wherein the lighter spring holds the spool in an overlapping closed position.

Abstract: A meter-out load sensing hydraulic system controlling one or more motors, supplied by a variable displacement pump through a directional control valve. The compensating means of the pump senses pressure and flow on the discharge or return side of the motor to determine the pump cam plate position. The signal line connecting this discharge side of the motor to the compensating means is also supplied with a low pressure signal flow which causes the pump to standby at a low pressure level in a neutral valve position or when metering down a gravity load.

Abstract: A sequencing valve utilized with a tractor-propelled planter having two row arms which pivot downward to the ground in an alternating sequence as the planter changes directions in the field. The sequencing valve is connected with the conventional hydraulic system which raises and lowers the planter at the end of each row so as to automatically lower alternate marker arms. This is achieved by pressurizing opposite ends of the sequencing valve spool for longitudinal movement through a cam means, causing the spool to rotate during movement in one direction whereby alternating lowering of the planter arms is achieved each time the planter is hydraulically lowered to the ground.

Abstract: A hydraulic stabilizing device utilized to dampen the sway of railway cars comprising a double acting hydraulic cylinder having a center position wherein the fluid is locked in the opposing chambers of the cylinder except for high pressure relief once the piston is forced out of the center position as the railway car traverses a curve. Longitudinal groove means in the cylinder barrel opens up a restricted bypass across the cylinder piston so as to allow a conventional dampening function at all other positions of the cylinder except the center position. The stabilizer cylinder also includes a concentrically spaced sleeve surrounding the cylinder forming a precharged accumulator chamber for resupplying either of the cylinder chambers through check valves in the cylinder heads.

Abstract: An improved rephasing master cylinder in which the cylinder wall approximate the end of the cylinder has a longitudinal bleed passage in the cylinder wall at one end connected to a lateral passage opening into the forward cylinder chamber while the opposite end of the longitudinal passage connects with the rearward chamber of the cylinder when the cylinder piston is located therebetween. This longitudinal bleed passage permits the restricted flow past the master cylinder piston when the piston is nearing and at the end of its stroke, thereby causing both master and slave pistons to complete their respective strokes.

Abstract: A relief valve with a low hysteresis closing curve with a fixed seat and a spring-biased poppet which is guided for longitudinal movement by an axial guide sleeve and aligns with its seat by pivoting about a fixed point through a small angle of rotation.

Abstract: The invention is an improved pressure compensating flow limiting valve which maintains an optimum performance curve at differing flow rates. The invention is the specific placing of a vent passage in the valve spool immediately downstream of the fluid jet passing across the spool in a metering mode with the vent passage connected to one of the servo chambers which positions the spool. The effect of the exiting fluid jet draws some fluid from the vent passage thereby dropping the pressure level in that servo chamber sufficiently to offset certain dynamic forces on the spool and balance the spring forces on the spool with these forces regardless of the flow rate through the valve.

Abstract: A self-leveling series type hydraulic system including boom and bucket valves which separately control boom and bucket cylinders and a flow divider valve positioned in the exhaust flow path from the rod end of the boom cylinder. The flow divider valve splits the flow sending a portion of it to the cap end of the bucket cylinder so as to maintain the bucket in a level condition during raising of the boom with the remaining flow connected to one of the boom valve motor ports whereby the bucket valve can be separately actuated concurrent with the boom valve and supplied with oil so as to override the self-leveling function if desired.

Abstract: A warm-up valve in a load responsive hydraulic system which connects the pump discharge pressure with the pump compensator while bypassing to reservoir a partial capacity of the pump. When proper reservoir temperature is reached, a thermostatically controlled solenoid closes the warm-up valve causing the pump to return to low pressure standby.

Abstract: A signal bleed-down valve in a load responsive system which is positioned in the sensing line between the pump compensator and control valve. The valve in the absence of sufficient pilot pressure opens the pump compensator to drain. Otherwise, the valve is controlled by pilot flow across a fixed orifice in the spool which creates a pressure drop acting against a spring, and moves the valve spool to a position metering the pilot flow so as to maintain a constant flow level across the valve spool regardless of the pressure level.

Abstract: A removable plug used for setting land timming of a control valve spool or spring loading in relief valves. The plug has deflectable contact points which deform in its plastic range against the harder surface of the valve body as the plug is screwed into the valve body to position the spool for precise and repeatable land timming.

Abstract: A hydraulic valve in a load responsive pressure flow compensated system for operating a header height cylinder including a lockout check valve which is opened by an accompanying plunger experiencing pressure in an adjacent motor port. Said plunger includes a metering notch opening to drain when the plunger is actuated, said metering notch is sized larger than the flow-sensing notch on the valve spool so that while lowering the machine header, the pressure compensating means of the system does not go to full pressure compensation level but rather stands by at the low pressure level relieved across the lockout actuating plunger. The valve further includes metering notches in the control valve spool which are so shaped that a FLOW vs. TIME curve of the spool from the neutral position to an operating position has a plateau at a time interval from zero which is substantially equal to one-half of the cycle time of the natural frequency of the machine.

Abstract: Hydraulic "squeeze cylinders" control the size of the discharge orifice on an extrusion baler and are operated by a control circuit that relieves pressure in the cylinders in response to the build-up of a certain predetermined pressure level in the circuit. Pressurized fluid for the squeeze cylinders is supplied by a single-acting pump cylinder that is connected between the plunger head and its pitman rod in such a way as to deliver a charge of pressurized fluid into the circuit on each compression stroke of the plunger. A pilot-operated relief valve is operated by circuit pressure when the latter reaches a predetermined pressure level to block flow from the pump cylinder and open a relief path for fluid in the squeeze cylinders.

Abstract: A solenoid powered flow control valve in which the valve spool has split the pump flow across a primary metering orifice and a pilot metering orifice which regardless of spool position maintains a substantially constant flow ratio between the main and pilot flow. The valve spool is controlled by opposing servo chambers which sense the pressure drop in the pilot flow path across a solenoid powered variable orifice.

Abstract: This lower link for a three-bar hitch provides a practical way to determine the tension force present in a lower link independent of any bending or other loadings. The link is formed of two bars which are bent out from each other to an intermediate point and then converge together forming a diamond-shaped opening between the bars and the distance between the intermediate points on the bars is measured by a length measuring device; the length being translatable into the tension force on the link.

Abstract: A phase and speed control system for synchronizing the speed and controlling the phase relationship between a pair of aircraft engines, each engine having associated therewith a centrifugal governor, includes a phase comparator circuit which provides a pulse width modulated signal only to the governor coil of the engine having the slower initial rotational velocity. A variable delay on one input of the phase comparator may be adjusted to determine the relative rotational phase relationship between the engines.

Abstract: This invention is a specific method for shaping the shank of a hydraulic control valve spool to alter the momentum exchange from high pressure fluid flowing across the spool so as to balance the various dynamic forces acting on the spool. The shank is shaped to turn the high velocity stream away from the spool at a lesser angle than the entry angle of the stream while utilizing conventional square-edge lands.

Abstract: A conventional control valve hydraulically powered by a double acting cylinder and controlled electrically through a double acting solenoid supplied by a variable D.C. supply. The solenoid transmits varying forces to a four-way pilot valve which in turn controls the positioning of the double acting cylinder. The de-energized solenoid, control valve spool and pilot spool are neutrally balanced between two springs equally loaded with differing spring rates so that a small movement of the solenoid core will cause a proportionally larger movement of the main control valve spool proportioned to the different spring rates.

Abstract: A gyroscopic device of the type having a short-circuited rotor winding or conductor so shaped so as to produce axial and radial flux components when rotated in the earth's magnetic field is coupled to a coaxial sensing coil coaxial which gyroscopically stabilized thereby, signals induced in the sensing coil due to the axial flux component of the rotor is used to derive magnetic heading information and there is provided at least one further coil on the supporting body and inductively linked to the sensing coil and rotor such that when the sensing coil is gyroscopically stabilized by the rotor, the coil supported on the supporting body in relation to the gyroscopically stabilized sensing coil is such that any changes in angular orientation of the supporting body relative to the gyroscopically stabilized sensing coil introduces changes in the signal voltages induced in the coils.