3284 results about "Hydraulic circuit" patented technology

The invention comprises a method, an article, and a control system for controlling a powertrain having a main and an auxiliary hydraulic pump, with each pump operative to supply hydraulic fluid to a hydraulic circuit of the transmission. It includes determining a main pressure and a desired main pressure, and controlling the auxiliary hydraulic pump. Determining a main pressure in the hydraulic circuit comprises estimating hydraulic pressure. The auxiliary pump is controlled to an operating speed. Control of flow from the auxiliary and main pumps can comprise an exclusive ‘either-or’ flow, or a blended flow.

A method and apparatus are provided to control operation of an electro-mechanical torque transmission device selectively operative in one of a plurality of fixed gear modes and two continuously variable modes, and operative to transmit torque input from a plurality of torque-generative devices. The transmission device includes a hydraulic circuit and is operative in one of a plurality of operating modes by selective actuation of a plurality of hydraulically-actuated torque-transfer clutches. The method comprises monitoring pressures in the hydraulic circuit, and restricting operation of the transmission when any one of the monitored hydraulic pressures does not correspond to an expected pressure thereat. Presence of a fault is verified during the restricted operation.

Regenerative shock absorber. A piston is disposed for reciprocating motion within a cylinder as a vehicle's suspension system deflects. Hydraulic fluid passes through an hydraulic motor to turn its shaft. The hydraulic motor shaft is connected to an electric generator to generate electricity. Flow characteristics of hydraulic circuits are selected to provide suspension system damping for appropriate wheel control.

An electronic winch monitoring system for a winch having a fixed-ratio gearbox with input and output shafts, a winch drum connected to the output shaft, and an auxiliary brake connected to the output shaft activated by reducing the pressure in a brake release hydraulic circuit. The system comprises an input shaft speed sensor, an output shaft speed sensor, and an electronic control unit having a monitoring section and a brake control section. The monitoring section receives the speed signals, processes them to produce a calculated ratio of actual input to output shaft speeds, and produces a fault indication signal when the value of the difference between the calculated speed ratio and the fixed ratio exceeds a predetermined value. The brake control section, upon receiving the fault signal, reduces the hydraulic pressure in the brake circuit using a nonlinear pressure-time profile to engage the auxiliary brake and stop the winch drum.

Lost motion systems and methods for providing engine valves with variable valve actuation for engine valve events are disclosed. The system may include a master piston hydraulically linked to a slave piston, and a dedicated cam operatively connected to the master piston. The slave piston may be disposed substantially perpendicular to the master piston in a common housing. The slave piston is adapted to actuate one or more engine valves. The slave piston may incorporate an optional valve seating assembly into its upper end. A trigger valve may be operatively connected to the master-slave hydraulic circuit to selectively release and add hydraulic fluid to the circuit.

A fluid exchanger for servicing the fluid circuits of vehicular power steering systems and other fluid circulating or hydraulic circuits. The fluid exchanger uses a float operated fluid control valve to harness fluid pressure provided by a pump of an accessed hydraulic circuit. The fluid control valve uses both negative and positive pressure of the circuit's pump to control fluid flow patterns. The float and fluid control valve are matched to be either mechanical/hydraulic or electrical/hydraulic in design. If the exchanger is provided with a mechanically operated fluid control valve, a mechanical float is provided in the exchanger's fresh fluid reservoir and is directly connected to the valve slide of the fluid control valve. If the exchanger is provided with an electric solenoid operated fluid control valve, a float operated electrical switch is provided in the exchanger's fresh fluid reservoir and is wired to control the solenoid of the valve.

A method and apparatus for formation testing is disclosed. In a preferred embodiment, a formation testing tool includes a longitudinal body with a flowbore; a plurality of extendable centralizing pistons coupled to the body; an extendable sample device coupled to the body; and a centralizing hydraulic circuit configured to cause each of the plurality of centralizing pistons to extend at substantially the same rate. The centralizing hydraulic circuit includes a series of flow control and pressure-determining valves configured to extend the centralizing pistons at substantially the same rate, and to help maintain stability in the hydraulic circuit in response to external pressures. In some embodiments, the extendable sample device is preferably configured to be recessed beneath a surface of the body in a first position and to extend beyond the surface in a second position. The extendable sample device is preferably extended to contact the borehole wall substantially normal to the wall, protecting the sample device from excessive bending moments and other excessive forces.

In one aspect of the present invention a drill bit assembly has a body portion intermediate a shank portion and a working portion. The working portion has at least one cutting element and the body portion has at least a portion of a jackleg apparatus. The jackleg apparatus has at least a portion of a shaft disposed within a chamber; the shaft has a distal end. The jackleg apparatus has a hydraulic compartment adapted to displace the distal end of the shaft relative to the working portion. The chamber also has an opening proximate the working portion of the assembly. The hydraulic compartment may be part of a hydraulic circuit which has a pump. The pump may have a first section with is rotationally fixed to the body portion and a second section rotationally isolated from the body portion.

A hydraulic circuit has a rotary type pump comprising a rotor rotating with a driving shaft and a casing which holds the rotor and the driving shaft. The casing further comprises an inlet port through which fluid is introduced to spaces formed by the rotor, an outlet port through which fluid is discharged from the spaces, and a hydraulic path for leading fluid from clearance around said driving shaft to the outside of the casing. A reservoir is provided to store fluid coming through the hydraulic path. A return conduit is disposed between the reservoir and an upstream side conduit connected to the inlet port in order that fluid stored in the reservoir is returned to the upstream side conduit. In the return conduit, a check valve is disposed to prevent the reverse flow of fluid from the upstream side conduit to the reservoir.

A hydraulic circuit that enables smooth absorption of the energy of a return fluid from a hydraulic actuator by means of an energy recovery motor. A return fluid passage to which the fluid discharged from a boom cylinder is branched is provided at the tank passage side of a solenoid valve of a boom control circuit. The return fluid passage comprises two return passages, which are provided with a flow rate ratio control valve for controlling a ratio of fluid that branches off into the return passages. The flow rate ratio control valve is comprised of a solenoid valve disposed in the return passage, which is provided with an energy recovery motor, and a solenoid valve disposed in the return passage, which branches off the upstream side of the solenoid valve.

Methods and apparatus for making and breaking tubular connections within a tubular string are disclosed. In certain aspects, a tong assembly includes gated power and back up tongs coupled to a torque bar. Jaws of the tongs may be arranged circumferentially with support members disposed between adjacent jaws to substantially complete a 360° closed circle. A hydraulic circuit may equally distribute fluid and pressure to actuate the jaws. The power tong may include a gated rotor driven by at least three drive motors. The rotor may be selectively physically locked from rotation or movement by one or more rotor locks. Further, the tong assembly may include an interlock that prevents activation of the drive motors until the rotor locks actuate to unlock the rotor. Additionally, gate locks may secure the tongs and rotor when closed, and a releasable coupling arrangement may aid engagement of a motor to a rotor pump.

A beverage dispensing machine includes: a first hydraulic circuit including a water source, a pump, a water heater, a brewing device selected from a brewing chamber and a capsule, the brewing device including an inlet and outlet, a beverage collector collecting brewed beverage leaving the brewing device and for dispensing the beverage to a container; and a second hydraulic circuit that includes a second pump and second water heater, the outlet of the second water heater being connected to the first circuit at a location that is downstream to the brewing device with respect to the water flow in the first circuit. The first circuit can maintain in the brewing device a pressure substantially constant for a pre-set time, the pressure being less that an opening pressure for the brewing device.

Hydraulic circuits used to manipulate tools in, for example construction equipment, uses less power for a retraction of a hydraulic cylinder than for an extension of that cylinder. Provided is a hydraulic circuit that uses the stored energy from the low energy phase to lower the energy load on the hydraulic pump during the high energy phase. Energy from the hydraulic pump is increased during the low energy phase to increase the amount of stored hydraulic energy. The increased amount of stored energy is then used to intensify or add to the energy generated by the hydraulic pump for the high energy phase.