Abstract: A method of making a solenoid actuator by laser direct metal deposition can comprise heating with a laser an outer surface of a circumferential groove of a solenoid tube blank constructed of a first material to create a heated area and depositing a second material upon the heated area to form a layer of second material. The second material can melt and then cool to thereby bond to the solenoid tube blank. A bore can be defined in the solenoid tube blank such that the bore includes an interior surface having a ring of second material disposed between a pair of portions of first material.

Abstract: A proportional motion control valve includes an electro-mechanical actuator that provides an infinitely controlled pressure setting in response to an electric signal applied to the electro-mechanical actuator. In another aspect, a proportional motion control valve includes a pilot-operated valve disposed intermediately with respect to a cage and a valve body to fluidly isolate an internal cavity of the valve body from a bore of the cage. The pilot-operated valve is subjected to a hydraulic opening force of pilot fluid that is present in the bore of the cage. A spring is disposed within the internal cavity of the valve body and arranged to subject the pilot-operated valve to a closing spring force.

Abstract: An integrated three-way poppet valve is disclosed with an intermediate pilot port and an integral load holding check valve. The valve incorporates a reverse flow check poppet for load hold capability, which enables a lower cost solution compared to a combination of valves of similar functionality. A control method is also disclosed using an integrated three-way poppet valve to control the flow of hydraulic oil to a cylinder, hydraulic motor, or other hydraulic device in proportion to the amount of a current applied to a solenoid coil. Depending on the current applied, the valve blocks all flow or else permits flow from one inlet port to two outlet ports proportional to the current applied.

Abstract: A method of making a solenoid actuator by laser direct metal deposition can comprise heating with a laser an outer surface of a circumferential groove of a solenoid tube blank constructed of a first material to create a heated area and depositing a second material upon the heated area to form a layer of second material. The second material can melt and then cool to thereby bond to the solenoid tube blank. A bore can be defined in the solenoid tube blank such that the bore includes an interior surface having a ring of second material disposed between a pair of portions of first material.

Abstract: An integrated three-way poppet valve is disclosed with an intermediate pilot port and an integral load holding check valve. The valve incorporates a reverse flow check poppet for load hold capability, which enables a lower cost solution compared to a combination of valves of similar functionality. A control method is also disclosed using an integrated three-way poppet valve to control the flow of hydraulic oil to a cylinder, hydraulic motor, or other hydraulic device in proportion to the amount of a current applied to a solenoid coil. Depending on the current applied, the valve blocks all flow or else permits flow from one inlet port to two outlet ports proportional to the current applied.

Abstract: A hydraulic circuit is disclosed that can include a flow control element, a pressure compensator connected via a pair of load sense lines to an inlet line and an outlet line, respectively, of a flow control element to provide a constant pressure drop across the flow control element, and a load sense line control valve installed in a load sense line to provide controllable resistance in a flow passage in opposite flow directions, the resistance in each flow direction being different. The load sense line control valve can include a restrictive orifice followed by a spring-loaded check valve in a first flow direction and at least one other restrictive orifice and a check valve in a second flow direction, the second flow direction opposing the first flow direction.

Abstract: A self-cleaning filter for use in a valve is disclosed. The valve can include a bore, an orifice disposed in the bore for accommodating a fluid flow therethrough, and a filter disposed in the bore between the input port of the fluid flow being filtered and the orifice being protected. The filter can include an entrance head in predetermined spaced relationship with the bore of the valve to define a filter entrance and a body portion. The entrance head can be configured to prevent particles of a predetermined size from entering the filter entrance. The body portion can include at least a portion that has a different shape than the entrance head which cooperates with the bore to define a fluid passage. The fluid passage can have an exit port which is communicable with the orifice to send filtered fluid to the orifice. The filter can include an offset portion which extends beyond an end face of the bore which is useful to develop pressure gradients which provide for a self-cleaning function.

Abstract: A cartridge relief valve uses a piston design. The piston replaces a tube used in prior art relief valves. The piston makes the inventive relief valve easier to manufacture and more stable than prior art relief valves. This is due to the fact that, for a given size valve, the diameter of the piston is smaller than the diameter of the tube that it replaces. Furthermore, the diameter of the pilot seat of the inventive relief valve is also smaller than the diameter of the pilot seat of many prior art valves.

Abstract: A flow regulator with pressure relief combination valve is disclosed which can include a housing and a valve assembly. The housing can have a chamber and four ports. A cage, having a plurality of cross holes, is supported by the housing. A hollow spool is slidably disposed within the cage and is biased to engage the cage. A shoulder of the cage and a counterbore of the spool cooperate to interferingly retain an insert. A poppet is slidably disposed inside of the cage. The valve assembly includes an adaptor, a spring disposed within the adaptor, a guide disposed between the spring and the poppet, and an adjuster adjustably secured to the adaptor. The spring is arranged to bias the poppet against a seat via the guide. The adjustor is movable to adjust the position of the spring.

Abstract: A hydraulic circuit is disclosed that can include a flow control element, a pressure compensator connected via a pair of load sense lines to an inlet line and an outlet line, respectively, of a flow control element to provide a constant pressure drop across the flow control element, and a load sense line control valve installed in a load sense line to provide controllable resistance in a flow passage in opposite flow directions, the resistance in each flow direction being different. The load sense line control valve can include a restrictive orifice followed by a spring-loaded check valve in a first flow direction and at least one other restrictive orifice and a check valve in a second flow direction, the second flow direction opposing the first flow direction.

Abstract: A proportional, pilot-operated flow control valve is disclosed which can include a cage, a hollow compensating spool slidably disposed within the cage, a hollow metering guide member slidably disposed within the compensating spool, a regulating spool slidably disposed within the guide member, a dampening guide slidably disposed inside the compensating spool to define a dampening chamber, a compensating spring disposed inside the dampening chamber and arranged to urge the dampening guide to engage the metering guide and the compensating spool to engage the cage, a regulating spring disposed inside the regulating spool and urging the regulating spool to abut the dampening guide, and a cartridge, the cartridge having a pilot valve assembly and an adaptor, the adaptor mounted to the cage, the pilot valve assembly mounted to the adaptor, the pilot valve assembly including an actuator.

Abstract: A cartridge relief valve is uses a piston design. The piston replaces a tube used in prior art relief valves. The piston makes the inventive relief valve easier to manufacture and more stable than prior art relief valves. This is due to the fact that, for a given size valve, the diameter of the piston is smaller than the diameter of the tube that it replaces. Furthermore, the diameter of the pilot seat of the inventive relief valve is also smaller than the diameter of the pilot seat of many prior art valves.

Abstract: A flow regulator with pressure relief combination valve is disclosed which can include a housing and a valve assembly. The housing can have a chamber and four ports. A cage, having a plurality of cross holes, is supported by the housing. A hollow spool is slidably disposed within the cage and is biased to engage the cage. A shoulder of the cage and a counterbore of the spool cooperate to interferingly retain an insert. A poppet is slidably disposed inside of the cage. The valve assembly includes an adaptor, a spring disposed within the adaptor, a guide disposed between the spring and the poppet, and an adjuster adjustably secured to the adaptor. The spring is arranged to bias the poppet against a seat via the guide. The adjustor is movable to adjust the position of the spring.

Abstract: A cartridge relief valve uses a piston design. The piston replaces a tube used in prior art relief valves. The piston makes the inventive relief valve easier to manufacture and more stable than prior art relief valves. This is due to the fact that, for a given size valve, the diameter of the piston is smaller than the diameter of the tube that it replaces. Furthermore, the diameter of the pilot seat of the inventive relief valve is also smaller than the diameter of the pilot seat of many prior art valves.

Abstract: A hydraulic valve with a position sensor is described. According to various implementations, the valve has a cage with a set of radial holes, a spool assembly slideable within the cage, and a sensor, which may be a Hall effect sensor, that reacts to the movement of the spool assembly. In other implementations, the spool comprises one or more of the following: a spool, a pin that is mechanically coupled to the spool, a dampener, which may be a spring, having a first and a second end, the first end being in contact with the pin and the second end being in contact with the spool.

Abstract: A proportional, pilot-operated flow control valve is disclosed which can include a cage, a hollow compensating spool slidably disposed within the cage, a hollow metering guide member slidably disposed within the compensating spool, a regulating spool slidably disposed within the guide member, a dampening guide slidably disposed inside the compensating spool to define a dampening chamber, a compensating spring disposed inside the dampening chamber and arranged to urge the dampening guide to engage the metering guide and the compensating spool to engage the cage, a regulating spring disposed inside the regulating spool and urging the regulating spool to abut the dampening guide, and a cartridge, the cartridge having a pilot valve assembly and an adaptor, the adaptor mounted to the cage, the pilot valve assembly mounted to the adaptor, the pilot valve assembly including an actuator.

Abstract: A dual proportional pressure control valve can include a cage, a spool, and an electromagnetic proportional actuator having a pair of coils. The control valve can deliver a stable secondary pressure to one of two different load ports from a primary pressure source. Which load port receives the secondary pressure can be dependent upon which coil of the activator is energized. Since the spool is driven directly by the electromagnet to control its sliding position, its secondary pressure can correspond to the strength of the electromagnet-energizing current. Secondary pressure feedback from the load port can act on an area defined by lands of the spool, which can have different diameters, or on the area formed by an axial hole in each end of the spool, thereby making the secondary pressure more controllable against disturbances.

Abstract: A self-cleaning filter for use in a valve is disclosed. The valve can include a bore, an orifice disposed in the bore for accommodating a fluid flow therethrough, and a filter disposed in the bore between the input port of the fluid flow being filtered and the orifice being protected. The filter can include an entrance head in predetermined spaced relationship with the bore of the valve to define a filter entrance and a body portion. The entrance head can be configured to prevent particles of a predetermined size from entering the filter entrance. The body portion can include at least a portion that has a different shape than the entrance head which cooperates with the bore to define a fluid passage. The fluid passage can have an exit port which is communicable with the orifice to send filtered fluid to the orifice. The filter can include an offset portion which extends beyond an end face of the bore which is useful to develop pressure gradients which provide for a self-cleaning function.

Abstract: Disclosed is a valve having one or more ports. The valve comprises a spool slidably disposed within the valve and a generally circular retainer disposed so as to prevent the spool from moving along an axis of the valve. The retainer is capable of opening so as to permit the spool to move along the axis of the valve.

Abstract: A proportional, pilot-operated directional valve has a sleeve with at least four sets of radial holes, and a spool disposed within the sleeve, with a channel being defined between the spool and the sleeve. The spool has at least two sets of radial holes, and the exterior surface of the spool has annular protrusions, each being in at least partial contact with the inner wall of the sleeve. When the valve is in an open position, the first set of radial holes of the sleeve is in communication with one of the two sets of radial holes of the spool, the second and third sets of radial holes of the sleeve are each at least in partial communication with the channel, and the fourth set of radial holes of the sleeve is in communication with the other of the two sets of radial holes of the spool. The spool may be kept in an open position by pressure from a flow of fluid that is provided at one end of the sleeve.