Abstract: A holddown pin mechanism for hydraulic power units is a ball guide with a cylindrical flat base having a central opening, a plurality of spaced elongated holddown pins have one end rigidly secured to one side of said ball guide. The pins extend outwardly at right angles from the side of said washer to which they are secured. The holddown pin mechanism is placed in a hydraulic cylinder block having a center bore, with the pins extending into holes in the block. A flat washer on a shaft extending through the block engages the free ends of the pins.

Abstract: A steering system for a work vehicle adjusts the steering ratio in response to changes in the speed of the work vehicle.

Abstract: An electronic traction control system for a vehicle having multiple hydraulic driven wheels includes a plurality of digital displacement pumps, a plurality of drive systems having counterbalance valves and motors used to drive wheels, and electronic flow control valves used in association with each drive assembly. Additionally the system has a steering mechanism that is electrically connected to a digital sensor and a proportional sensor that sends signals to a system controller that operates the functioning of the digital displacement hydraulic pumps.

Abstract: A hydraulic circuit arrangement with a fixed displacement pump driven by an electric motor, a lifting cylinder, a load-holding valve arranged in the line between pump and lifting cylinder, a priority valve, which is acted upon by the pump, being arranged between pump and load-holding valve and distributing the volumetric flow flowing from the pump to the lifting cylinder, on the one hand, and to at least one further consumer of a load-sensing system, on the other hand. In the first of its two extreme positions, the priority valve connects both the lifting cylinder and the at least one further consumer in each case to the pump and, in the second of its two extreme positions, only connects the at least one further consumer to the pump while the lifting cylinder is completely cut off.

Abstract: The invention relates to an axial piston machine having an bent axis segment which is adjustable by means of an actuating piston, and a variable unit for the electrically proportional adjustment of the displacement. The variable unit has a control piston for controlling the oil pressure which displaces the actuating piston, an electrically controllable proportional solenoid which acts on the control piston, a feedback spring on the control piston for retracting the instantaneous Bent axis valve segment and a adjustment mechanism for setting the start current. To set the start current, the adjustment mechanism has a setting spring which acts on the armature of the proportional solenoid with an adjustable force.

Abstract: A tilt sensor and a method for the use of the tilt sensor to calculate the degree of tilt, whereby the tilt sensor has at least three accelerometers mounted to a base, the accelerometers are positioned in a common plane, and wherein each is preferably at an equally spaced angle from one another.

Abstract: The invention relates to an axial piston engine having a swash plate, or a bent axis with a valve segment, which can be adjusted by means of a servo piston, and having an adjustment unit for electrically proportionally adjusting the supply volume. The adjustment unit has a regulating piston for controlling the oil pressure which moves the servo piston, electrically actuable proportional magnets which act on the regulating piston, and a feedback device for feeding the instantaneous swash plate position or bent axis valve segment position back to the regulating piston. The feedback device has a tappet which is mechanically coupled to the swash plate or to the bent axis valve segment, in each case one leaf spring being arranged in the longitudinal direction at both sides of said tappet, said leaf springs enclosing a feedback lever which is mounted in the regulating piston.

Abstract: The invention relates to a circuit for enabling or disabling a braking system of a hydraulic propel drive, having a device for checking operating parameters which are relevant to a neutral setting and having a spring device, in particular a load spring, which acts counter to the control piston of an electrohydraulic solenoid valve which is designed to enable the braking system by means of electrical operation. A device for generating a force, which is dependent on the neutral position, of the spring device is provided, wherein when a neutral setting is not present, the force action of the spring arrangement prevents the electrohydraulic solenoid valve from enabling the braking system, by acting counter to the electrical operation of the magnet of said solenoid valve.

Abstract: The invention relates to a circuit for enabling or disabling hydraulic actuating devices, in particular for enabling the braking system of a hydraulic propel drive, having a device for checking the pressure level in working lines or control lines of hydraulic circuits, a maximum or minimum pressure level being checked in two or more working lines or control lines. An ‘OR’ logic circuit is provided for checking the pressures. In said ‘OR’ logic circuit, two or more pistons are arranged in series in a common bore. In each case one of the pressures to be checked is introduced into one of the spaces between the pistons and the space between one of the pistons and the base of the bore.

Abstract: A valve arrangement in a hydraulic circuit comprises a longitudinal duct 3 and a transverse duct 2. A throttle slide 10 can be displaced in the direction of the longitudinal duct 3. Arranged in the throttle slide 10 is a valve piston 25, by means of which the flow through the hollow throttle slide 10 can be enabled or blocked. The flow of hydraulic fluid takes place through two groups of passage holes 33a, 35a, which are arranged in the throttle slide 10. The interaction of pressure and flow direction of the hydraulic fluid, and also the restoring force of a slide spring 20 and a piston spring 30, achieves a situation where hydraulic fluid can flow through the valve arrangement in both directions but that a throttling action occurs only when the hydraulic fluid flows from the transfer duct 2 to the longitudinal duct 3 under increased pressure.

Abstract: An electro-hydraulic power unit with an improved hydraulic fluid flow through the unit. The unit accomplishes the improved fluid flow by having an inlet port in a housing that is fluidly connected to an electric motor that has a rotor with vanes cast thereon and at least one opening within the rotor. A hydraulic pump inlet is fluidly connected to the electric motor such that the vanes of the electric motor will supply hydraulic fluid to the hydraulic pump inlet.

Abstract: An electro-hydraulic power unit is disclosed that includes a housing filled with hydraulic fluid. A hydraulic power unit is disposed within the housing, the power unit having a mechanical power shaft. Additionally, an electric machine is disposed within the housing adjacent to the hydraulic power unit, the electric machine having a rotor secured to the mechanical power shaft of the hydraulic power unit. Hydraulic fluid within the housing passes over the electric machine, thus cooling the electric machine and providing for improved efficiency and performance.

Abstract: A method of forming a control device includes the steps of positioning a magnet and a shaft in a die and die-casting zinc around the magnet and the shaft. The magnet is a sintered C-shaped magnet having opposing ends defining an open slot along the C-shaped main body. An anti-rotate pin is positioned in the die and is located at least partially within the open slot. Zinc is die-cast around the magnet, the shaft and the anti-rotate pin.

Abstract: A control device having an elongated shaft, a C-shaped magnet, and an anti-rotation pin. The magnet and the anti-rotation pin are encapsulated in a spherical member. The C- shaped magnet has opposing ends defining an open slot along the C-shaped main body. The anti-rotation pin extends through the slot and connects to the shaft.

Abstract: In the housing 1 of a hydraulic machine, the pressure Pi acts in the chamber 2. For this purpose, a passage opening 4 is provided, which is formed as a valve seat 5. A valve body 6 can be displaced longitudinally in the housing 1 and forms a pressure-tight spring chamber for an inner valve spring 21. The spring chamber is connected to the chamber 2 via a pressure equalizing hole 9. The prestress of the inner valve spring 21 can be set by means of a setting screw 18. In addition, there is an outer valve spring 22. Both the valve springs load the valve body 6 with the effect of closing it. The pressure equalizing valve described combines a compact design with an advantageous flow characteristic. When a maximum value of p1 is reached, the valve body 6 lifts off the valve seat 5 and hydraulic fluid from the chamber 2 flows away via the valve chamber 3.

Abstract: A hydrostatic module is disclosed, including a pair of shafts rotatably supported by a frame. Two yokes are pivotally mounted on the frame, each having complimentary surfaces to the other yoke and to the frame, minimizing the space occupied by the yokes. Stop means are provided on the yokes and on the frame to limit the pivotal movement of the yokes. A hydrostatic power unit is carried by each yoke, each connected to one of the shafts. A control system, having a single piece control housing containing servo pistons, pivots the yokes. The servo pistons independently determine the orientation of the yokes. A single piece fluid control porting plate is secured to the control housing to route hydraulic fluid to multiple locations within the control housing. A fluid manifold serves as a main structural element, with intimate proximity between the manifold and the control housing allowing simplified fluid exchange therebetween.

Abstract: A power switching assembly includes a circuit board mounted on an insulating substrate, a power switching transistor having a mounting surface mounted to the circuit board and a top surface located opposite the mounting surface, and a heat sink associated with the top surface of the power switching transistor, the heat sink operating to dissipate thermal energy from the top surface of the power switching transistor. The power switching assembly forms a part of a current inverter electrically connected between a direct current power source and an alternating current motor on a vehicle. The current inverter is adapted to converts DC current into three phase AC energy.

Abstract: In the stationary part (1) of an axial piston machine, a first flow duct (2) and second flow duct (5) intersect with the central axes (3) and (6). A valve body (20) having a valve cone (21) and a tubular guide piston which can be displaced in relation to the valve cone is situated in the extension of the central axis (3) of the first flow duct (2). The valve body (21) bears against a first valve seat (4) which is surrounded by an expanded section (7). The entire valve body (20) moves in a tubular partial housing (9) which is connected to the stationary part (1) in a sealed manner via a seal (11), a screw connection (10) and a flange (12) which rests on a shoulder (13) of the stationary part (1). A first compression spring (27) and a second compression spring (28) serve to support the valve body (20) and its parts in relation to one another. An extension stem (22) passes through the tubular guide piston and guides the second compression spring (28).

Abstract: The invention relates to a hydraulic pump or hydraulic motor having a rotating shaft, which is mounted in a fixed position in a housing and on which a pulse generator is provided, and having a rotation speed sensor, which is fixed to the housing and comprises a sensor element associated with the pulse generator, the sensor element being fitted eccentrically and offset with respect to the insertion axis of the rotation speed sensor.