Abstract: A fluid metering valve adaptable for outputting a fixed volume of lubricating oil from a diesel engine into an engine fuel system includes a sleeve slidably disposed in a body and a piston valve slidably disposed within the sleeve. A spring resiliently biases the sleeve to a default position blocking communication between a chamber and an outlet and the piston valve to a default position communicating an inlet with the chamber. The default position of the sleeve is established by a annular member resiliently biased into engagement with the body by another spring while the default position of the piston valve is established by another annular member urged into engagement with the body by a third spring.

Abstract: An overspeed control for a hydrostatic transmission of a mobile machine includes a speed control valve arrangement connected to a fixed displacement pump through a supply line and to a pressure responsive displacement controller of a variable displacement hydraulic pump of the transmission. An overspeed control valve is connected to the supply line and is operative for reducing the fluid pressure level in the displacement controller when the speed control valve arrangement is in an operative position and the rotational speed of the engine exceeds a predetermined level. This reduces the displacement of the variable displacement pump (which acts as a motor in a downhill situation) and thus increasing engine retarding and transmission losses for preventing the positive grade from accelerating the machine, engine and/or the components of the hydrostatic transmission to speeds exceeding their designed limits.

Abstract: Clutches in multi-speed transmission have been initially calibrated in an attempt to determine the point at which the clutch is filled and thus reduce the harshness of engagement of the elements within the clutches during future gear ratio changes in the transmission when being worked under normal conditions. In these earlier attempts at calibrating the clutches, the desired pressure level needed to fill the clutch was either empirically derived or calibrated by incrementally increasing or stepping the pressure level from a minimum value to the required value. In the subject invention, the clutches are calibrated by using a method of calibration that is substantially the same method that is used during normal operating conditions. By using substantially the same method, any effects of "hysteresis" of the associated valving is basically eliminated.

Abstract: A retaining device for axial piston machines embodies a shoe plate with a plurality of openings radially disposed in it. On each side of each opening a substantially flat portion exists to maintain a tangential line of radial contact with the shoes. The shoe plate has a force transferring portion made up of a plurality of raised surfaces. The raised surfaces are arranged to apply two areas of axial contact on each shoe. The two areas of axial contact are generally diametrically opposed which keeps the shoes in sliding contact with the swash plate and thus substantially eliminates tipping of the shoes.

Abstract: A method is provided for producing a piston assembly adapted for use in a hydraulic pump or motor and having an overall length shorter than previously known piston assemblies while maintaining a strong mechanical connection and a high, efficient volumetric output. The method includes the steps of forming a slipper with a spherical ball on one end; forming a piston having a body portion and a connecting portion, the connecting portion having a spherical bottom surface, a groove spaced from the bottom surface and a contoured portion having an angled outer surface and an inner surface; inserting the spherical ball into the cavity; forcing the contoured portion inwardly to place the inner surface into contact with the spherical ball and to substantially longitudinally align the outer surface of the piston body with the angled surface of the contoured portion; heat treating the piston to a predetermined hardness and depth; and finishing the total longitudinal length of the piston to a finished size.

Abstract: A coil assembly for a solenoid valve includes a sealing member having a sealed cavity that generally encircles an opening containing an electrical lead extending from the windings of the coil. The sealing member is disposed within a encapsulating material that is pressure molded around the windings of the coil assembly. During the pressure molding process, the pressure from the molding process exerts a force on the outermost side of the sealing member and compresses the outer member. The force being exerted to the outermost diameter is transferred through the sealed cavity to the innermost portion of the sealing member forcing it into a forced intimate contact with the lead. The force on the lead is maintained after the pressure from the molding process is removed. This arrangement provides a seal between the lead and the sealing member that is effective to prohibit damaging elements reaching the windings contained in the coil assembly.

Abstract: Accumulators normally are teed into existing conduits and require large amounts of space or are placed in spool type bores having a spring biased piston slidably disposed therein. Most times these accumulators require a bladder that is vented to the atmosphere or a fluid chamber connected to a reservoir. In the subject invention, an accumulator 24 is provided that has a fluid filled member 36 which can be disposed in a closed chamber 32 of a housing 30 and connected to a source of pressurized fluid. The fluid filled member 36 has a fixed maximum surface to volume ratio and is capable of being compressed when subjected to a pressure higher than the pressure within. The accumulator may be integral with other components in the hydraulic system 10 and can be made with varying volumetric capacities and varying precharged pressures in order to match the requirements of the hydraulic system.

Abstract: A hydraulic deceleration control for a hydraulic motor includes a pilot operated control valve for controlling fluid flow through a pair of motor lines connected to the opposite sides of the hydraulic motor. A valve device is disposed to communicate a source of pressurized fluid to a fluid energy storage device when the control valve is in its open position and to release the pressurized fluid contained in the storage device when the control valve is moved from the open position to its closed position. A throttle orifice releases the fluid from the storage device at a controlled flow rate. A pilot operated diverter valve is disposed in series with an orifice disposed between the motor lines to control fluid flow through the orifice and has a spring disposed at a first end resiliently biasing the diverter valve to its closed position.

Abstract: A centrifugal oil filter includes a housing having a rotatable bowl disposed in a first fluid chamber and rotatably disposed about a shaft extending through the first fluid chamber. The rotatable bowl has a flow directing member connected generally at the bottom thereof to define a particle collection basin and the flow directing member extends upwardly to form a passageway adjacent the shaft so that the fluid flow within the rotatable bowl is directed to a pair of nozzles which act to rotate the rotatable bowl responsive to fluid flow therethrough. A particle retention insert is made of a cellular structure and disposed in the particle collection basin. The particle retention insert functions to receive foreign particles within the cellular structure and retain them therein by protecting the particles from the fluid flow within the rotatable bowl.

Abstract: In machines having a bucket that is capable of carrying a load of material, it is well known that when the machine encounters a bump or other obstacle that the effects thereof may result in machine bounce or the operator is subjected to a jolt due to the sudden change in forces acting on the lift actuator of the lift mechanism. Accumulators have been connected to the loaded end of the actuator to provide a cushion or damping of the sudden changes in the forces. When the machine is being used without the accumulator connected to the loaded end of the actuator, the accumulator is normally connected to the loaded end of the actuator through an orifice in order to maintain a pre-charge in the accumulator equal to the pressure in the loaded end of the actuator. In order to ensure that the pressure in the accumulator is always equal to the pressure in the actuator, the accumulator is selectively connected to an auxiliary source of pressurized fluid.

Abstract: A hydraulic brake slack adjuster disposed between a brake valve and an actuator of a brake mechanism has a first piston exposed to pressurized brake fluid from the valve and a second larger piston connected to the first piston for outputting brake fluid to the brake actuator with the fluid output to the actuator being greater than the volume of input fluid from the valve. This permits a smaller pump to be used while maintaining sufficient brake operation speed.

Abstract: In machines such as hauling units having electro-hydraulic transmission controls, it is desirable to ensure that in the event of an electrical malfunction or power failure the transmission remains in the gear that it was in when the electrical malfunction occurred. In the subject invention, an independent latching system is provided in a transmission which in the event of an electrical malfunction automatically latches the transmission in the existing gear. This is accomplished by providing a master latch valve mechanism and a latching shuttle valve to act in cooperation with an electrically controlled proportional valve and a proportional valve that controls engagement of a plurality of hydraulically actuated clutches. When the transmission is operating normally, the master latch valve mechanism directs pressurized fluid from a source of pressurized fluid to urge the latching shuttle valve to an open position.

Abstract: Accumulators normally have a first chamber filled with a pressurized gas, a second chamber in communication with the pressurized fluid of a hydraulic system and an elastomeric member separating the chambers. In the subject invention, an accumulator is provided which has an elastomeric member disposed in a closed chamber of a housing. The elastomeric member has an outer surface with a non-uniform linear surface and a cavity extending inward from one end thereof and in communication with an inlet conduit. As the pressure is introduced into the cavity of the elastomeric member, the non-uniform linear outer surface is progressively forced against an interior surface of the closed chamber. The progressive compression of the elastomeric member acts to increase the volume of the cavity as the pressure of the fluid in the cavity progressively increases.

Abstract: In machines such as hauling units having electro-hydraulic transmission controls, it is desirable to ensure that in the event of an electrical malfunction or power failure the transmission remains in one of its gear ratios. In the subject invention, a dependent latching system is provided in a transmission which in the event of an electrical malfunction latches the transmission in the existing gear ratio or a gear ratio within at least two gears ratios. This is accomplished by providing a master latch valve mechanism, a logic valve arrangement, and a latching shuttle valve to act in cooperation with an electrically controlled proportional valve and a hydraulic proportional valve that controls engagement of a plurality of hydraulically actuated clutches. The master latch valve mechanism directs pressurized fluid from a source of pressurized fluid through the logic valve to urge the latching shuttle valve to an open position.

Abstract: Damping of the bounce in elastomeric tires is desirable to eliminate the tendency of a machine, such as a loader, to lope or bounce when carrying a load for a distance. The subject invention substantially reduces the lope or bounce by filling the cavity or closed chamber of a tire of a wheel assembly with a liquid, mounting an accumulator to a rim, and controllably interconnecting the closed chamber and the accumulator. By controlling the rate of fluid flow between the closed chamber and the accumulator, the elastomeric tire retains some resiliency while forcing the springs and shock absorbers of the machine to control the tendency for the machine to bounce or lope.

Abstract: A control system is provided for use in a hydraulic system to provide a simple arrangement with a limited number of elements that bypasses the system flow in the event of an electrical malfunction in the system and further allows other hydraulic circuits to operate even if one or more of the hydraulic circuits have experienced an electrical malfunction. The subject arrangement uses an electro-hydraulic fluid flow control valve mechanism in conjunction with directional valve mechanisms that have at least three functional positions and are controlled by associated electrically controlled displacement control mechanisms in response to receipt of electrical signals from an electrical controller.

Abstract: A method and apparatus for providing control of multiple actuators with a single control lever is provided. The method and apparatus is adapted for use in an electro-hydraulic system having a microprocessor, multiple actuators, respective electro-hydraulic directional control valves for each actuator, and individual control levers operatively associated with the microprocessor for controlling movement of the respective electro-hydraulic directional control valves. The method and apparatus is accomplished by providing a switch on each of the control levers that is operational to condition the microprocessor to direct simultaneous signals to the respective electro-hydraulic directional control valves to control each of the multiple actuators in proportion to the degree of movement of the one actuator when the switch thereon is depressed.

Abstract: A method is disclosed for controlling the shift points in a continuously variable transmission having a closed loop control wherein the output of the continuously variable transmission is generated by a hydrostatic transmission or by a combination of the hydrostatic transmission and a mechanical transmission having a summing planetary and high and low speed clutches.

Abstract: A method is provided for controlling the bounce of a work implement attached to a machine having an electro-hydraulic system. The method comprises the steps of sensing the operating pressure in an actuator arrangement connected between the frame of the machine and the work implement, monitoring an upper and a lower operating pressure level in the actuator arrangement to establish a threshold pressure level and altering the pressure level in the actuator arrangement in the event the threshold level is exceeded to re-establish the threshold pressure level. Once the original threshold level is attained, the system is reset. This effectively eliminates the bounce of the work implement at the initial onset of the bounce and resets the system to react to future bounces.

Abstract: A headlight mounting apparatus for a headlight having a bulb mounted therein. The subject headlight mounting arrangement has a mounting portion integral with the headlight, a retaining mechanism and associated hardware, and a grommet arrangement of unique cross-sectional configuration which alters the frequency of vibration to a value significantly less than the natural frequency of vibration of the headlight bulb filament. This arrangement reduces bulb failures caused by shock experienced during vehicle/machine operation.