Caterpillar Inc.

Shin Caterpillar Mitsubishi Ltd.

Noax B.v.

Francis J Raab

Willibald G Berlinger

Robert J Price

Brett M Bailey

Paul Curtis Pawelski

Trent Steven Kucher

John M Sloma

Roger Clayton Fales

Consistent with an aspect of the present disclosure, a method of locating a position of a movable member is provided. The movable member is movable along a path and has a surface with a plurality of markings provided thereon. The method includes sensing an image of a portion of the surface of the movable member, and calculating a position of the movable member based on the image. Further, the method includes determining whether the movable member is at a location corresponding to one of the plurality of markings, and eliminating an error associated with the position when the movable member is at the location corresponding to the one of the plurality of markings.

Hybrid optical cylinder position sensor

A hydraulic system for a work machine having a linkage system is disclosed. The hydraulic system has a tank configured to hold a supply of fluid and at least one hydraulic actuator associated with the linkage system to affect movement of the linkage system. The at least one hydraulic actuator has a first pressure chamber and a second pressure chamber. The hydraulic system also has an independent metering valve associated with the first pressure chamber. The independent metering valve has a valve element movable between a first position at which fluid communication between the first pressure chamber and the tank is blocked, and a second position at which fluid is allowed to drain from the first pressure chamber to the tank. The hydraulic system further has at least one sensor configured to sense a parameter indicative of a pressure in the second pressure chamber, and a controller in communication with the independent metering valve and the sensor. The controller is configured to move the valve element of the independent metering valve in response to the pressure.

Hydraulic system having variable back pressure control

A fluid control system may include a pump, a tank, and an actuator. A valve assembly may be configured to control fluid communication between the actuator, the tank, and the pump. An energy recovery circuit, including a pressure transformer, may be fluidly coupled to the actuator in parallel with the valve assembly.

Hydraulic control system with energy recovery

A free piston internal combustion engine, particularly suitable for use in a vehicle having an electric motor as a prime mover, has a combustion cylinder, a piston reciprocally disposed within the cylinder, and a piston rod coupled with a piston. A linear electric generator/motor includes at least one magnet carried by the piston rod and at least one coil positioned in association with the at least one magnet. An electrical circuit is coupled with each of the at least one coil and a battery. The at least one magnet induces an electrical cutrent within the coil to energize a capacitor within the electrical circuit. The charge from the capacitor may be used to charge the battery. The capacitor and/or battery provides output electrical current which is used to drive the electric motor.

Free piston engine with electrical power output

A free piston internal combustion engine includes a housing with a combustion cylinder and a second cylinder. A piston includes a piston head reciprocally disposed within the combustion cylinder; a second head reciprocally disposed within the second cylinder; a plunger rod with a first end attached to the piston head, a second end attached to the second head, and a longitudinal axis; and a plurality of radially extending vanes attached to the plunger rod and the second head. The radially extending vanes face toward the piston head and are disposed at an acute angle relative to the longitudinal axis.

Free piston internal combustion engine with rotating piston

A method of operating a free piston engine of the present invention, includes a housing with a combustion cylinder and a second cylinder. A piston includes a piston head reciprocally disposed within the combustion cylinder, a second head reciprocally disposed within the second cylinder, and a plunger rod interconnecting the piston head with the second head. A supply of hydraulic fluid is pulsed from a high pressure hydraulic accumulator into a pressure chamber in the second cylinder adjacent the second head during a beginning portion of a compression stroke to cause the piston head to move toward a top dead center position. The high pressure hydraulic accumulator is decoupled from the pressure chamber after the pulsing step. A low pressure hydraulic accumulator is coupled with the pressure chamber during a remaining portion of the compression stroke. The high pressure hydraulic accumulator is coupled with the pressure chamber when the piston head is traveling toward a BDC position during a return stroke. A sensor senses a position of the piston which is at or near the BDC position and provides a corresponding signal. The coupling between the high pressure hydraulic accumulator and the pressure chamber is maintained for a period of time, dependent upon the sensor signal.

Method of operating a free piston internal combustion engine with high pressure hydraulic fluid upon misfire or initial start-up

A pressure transformer is provided having a housing, with a rotating group disposed therein, an adjustable port plate is disposed between a barrel of the rotating group and a head portion of the housing. The barrel has a plurality of pistons slideably disposed in cylinders defined in the barrel. The cylinders each define a cylinder port that is in intimate contact with the port plate. The port plate has three arcuate slots defined therein and spaced from one another along a predetermined circumference. Each arcuate slot has a leading edge and a trailing edge. Likewise each of the cylinder ports has a leading edge and a trailing edge. The shape and orientation of the leading edges and trailing edges of the cylinder ports and the arcuate slots are the same. During relative rotation between the cylinder ports and the arcuate slots, the leading edges of the cylinder ports and the leading edges of the arcuate slots are radially concurrent. Likewise, the trailing edges of the cylinder ports and the trailing edges of the arcuate slots are radially concurrent. This relationship enhances the operating efficiency of the pressure transformer.

Porting for hydraulic pressure transformer

A pressure transformer is provided having a housing, with a rotating group disposed therein, an adjustable port plate is disposed between a barrel of the rotating group and a head portion of the housing. The barrel has a plurality of pistons slideably disposed in cylinders defined in the barrel. The cylinders each define a cylinder port that is in intimate contact with the port plate. Each cylinder port has a predetermined circumferential length. The port plate has three arcuate slots defined therein and spaced from one another along a predetermined circumference. Each arcuate slot has a leading edge and a trailing edge. Likewise each of the cylinder ports has a leading edge and a trailing edge. The shape and orientation of the leading edges and trailing edges of the cylinder ports and the arcuate slots are the same. The circumferential length of the space between adjacent ones of the arcuate slots is less than the circumferential length of the respective cylinder ports. During relative rotation between the cylinder ports and the arcuate slots, the cylinder ports is in communication with the adjacent arcuate slots but during operation the communication is effectively dynamically sealed. This relationship enhances the operating efficiency of the pressure transformer by conditioning the fluid within the cylinder so that the pressure therein is equivalent to the pressure in the successive arcuate port upon opening thereto.

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Edwards, IL, United States of America

Francis J Raab