A hydraulic valve assembly (1) with a housing (18) and with a spool (2) which is rotatable in the housing (18). The spool comprising a pressure supply orifice (3) and at least one clutch actuating orifice (4, 5) which is connectable to a clutch actuating cylinder (6, 7). The spool (2) comprises a pressure release orifice (8) which is arranged at the spool (2) so that the pressure release orifice (8) is closed by rotational movement of the spool (2) while the clutch actuating orifice (4, 5) is opened by such rotational movement. The invention further relates to a clutch actuating device with such a hydraulic valve assembly (1) and a corresponding marine propulsion system.

A method of controlling the electric current of a linear solenoid valve by performing pulse width modulation on a coil current for energizing a linear solenoid of the linear solenoid valve to adjust the hydraulic pressure of a working oil in a hydraulic clutch for transmitting and interrupting the rotational drive power from a power source to a drive wheel of a vehicle. The method includes setting the period of the pulse width modulation to a shorter value as the degree to which the hydraulic clutch is engaged increases from a disengaged state thereof. Here, the period of the pulse width modulation may be set in accordance with the variation of a duty ratio depending on the hydraulic pressure corresponding to the degree to which the hydraulic clutch is engaged.

A hydraulic control system includes a hydraulic pump driven by an electric motor, a solenoid valve having an output that controls the positions of a pressure regulator valve and a third, stator shift valve. The solenoid valve is a normally high, variable force solenoid valve which provides a control signal to the second and third valves. The second, pressure regulator valve is a multiple port valve which controls hydraulic fluid flow both to a transmission oil cooler (ATOC) and to an exhaust port, thereby maintaining a desired system pressure. The third, stator shift valve is also a multiple port valve and it controls fluid flow to the stator of the electric pump motor to provide cooling and to a dog clutch of the transmission to disengage it.

An electronic control device for controlling at least one rotatably arranged actuator includes electronic components, such as a device for the contact-free reception of electrical energy and the contact-free reception of signals, a device for generating magnetic fields, and a common housing that encloses the electronic components and assimilates them. The control device is rotatable and designed for attaching on or into a component rotating around a rotational axis.

Power transmission systems including clutch arrangements and systems are adapted to be used in marine and other environments. Such power transmission systems may include clutch arrangements that provide more effective power transmission capabilities as well as greater durability and longer life. Slipping clutch arrangements may effectively vary the output speed of a clutch arrangement from the speed of the engine or other driver as desired for the particular application. Various clutch arrangements also provide for greater flexibility and drive options, lighter weight, and diverse types of capabilities.

A hydraulic control device for an automatic transmission includes a shut-off valve arranged between a first pressure adjusting device and a respective shifting element cylinder of a plurality of shifting elements. In the first shifting position of the shut-off valve, the first pressure adjusting device is hydraulically connected to the respective shifting element cylinder through the shut-off valve. In the second shifting position of the shut-off valve, the shifting element cylinder is sealed by the shut-off valve relative to the first pressure adjusting device. The shut-off valve is an releasable check valve. The releasable check valve includes a check valve and an unblocking device. The unblocking device is actuatable by a control pressure from a second pressure adjusting device.

A method for controlling a line pressure of a hybrid vehicle includes applying, by a controller, a set current corresponding to a target pressure to a first solenoid valve controlling the line pressure, driving, by the controller, a second solenoid valve to open an engine clutch after the applying step, comparing, by the controller, a difference value between a real pressure of the engine clutch sensed by a pressure sensor and the target pressure with a preset pressure after the driving step, and as a result of performing the comparing step, if the difference value is equal to or greater than the preset pressure, controlling, by the controller, an increase of a revolution per minute (RPM) speed of the electric oil pump and an increase of a pressure of the first solenoid valve to be alternately generated.

A pressure control system for a torque control device includes a control pressure regulating valve (110) outputting a control pressure, a pressure switching valve (120) and a jointing pressure regulating valve (130) connected to a piston chamber of the torque control device. When the control pressure is lower than a set value of a spring of the pressure switching valve, the jointing pressure regulating valve (130) outputs jointing pressure that is in fixed proportion with the control pressure. When the control pressure reaches the set value of the spring of the pressure switching valve, the jointing pressure regulating valve (130) outputs a jointing pressure that is larger than the fixed proportion with the control pressure. The pressure control system ensures that the torque control device has both precise and large torque capacity.

A filtering device includes a tubular outer body with an intermediate chamber containing a pair of cup-shaped valve elements mounted floating and slidable coaxially with opposing cavities in which an axially compressed spring is housed. The first cup-shaped valve element is arranged coaxially outside the second cup-shaped valve element and has a base with a central through opening and a tubular portion with a series of ribs. The second cup-shaped valve element has a perforated base abutting against a perforated plug fixed to one side of the cavity passing towards the master cylinder. The perforated plug forms a through seat that slidably houses an appendage of the second cup-shaped valve element. Passages are formed around the plug that establish fluid communication between the intermediate chamber and a passage to the master cylinder.

Provided is a system and method for controlling a clutch plate assembly of a vehicle. The system may include a first clutch control system, a second clutch control system, and a valve system. The valve system may have a first input fluidly connected to the first clutch control system for receiving a first pressure from the first clutch control system, a second input configured to be fluidly connected to the second clutch control system for receiving a second pressure from the second clutch control system, and an output configured to be fluidly connected to the clutch plate assembly. The valve system may be configured to provide at least a portion of at least one of the first pressure and the second pressure to the clutch plate assembly.