A wheelchair lift system for a vehicle comprises: a platform for accommodating a wheelchair; a lifting arm; a hydraulic circuit including a hydraulic actuator arranged to act on the lifting arm to raise and lower the platform; a barrier mounted on the platform and pivotable between a raised position and a lowered position; a plurality of sensors each arranged to generate a sensor output; a user input device arranged to generate control signals to control operation of the lift; and a control unit. The control unit is arranged to receive the control signals and to receive the sensor output from each of the sensors and to control the hydraulic circuit thereby to control of the lift to perform a number of different operations. The control unit is also operable in a fully operational mode and a safety mode and is arranged to perform a plurality of checks on the sensor outputs, and to record a result of each of the checks, and to switch between the fully operational mode and the safety mode based on the results.

A monitoring system (500) of an on/off type actuator device (1) for activating a valve for fluid pipelines is described, the actuator device (1) being configured to move a valve member of said valve between a first position and a second position. The actuator device (1) comprises at least one fluid cylinder (6) configured to control a linear movement of an actuator rod (8). The monitoring system (500) comprises a plurality of sensors mounted on the actuator device (1) and configured to detect a plurality of operating parameters of the actuator device, and an electronic processing and control unit (50). The electronic processing and control unit (50) is configured to impart a micro-movement to the valve member, to detect signals indicative of the values of said operating parameters during said micro-movement of the valve member, and as a function of said values of said detected operating parameters to estimate if said actuator device (1) is capable of applying a torque or force value sufficient to make said valve member perform the entire movement from the first position to the second position. The micro-movement is such as to constitute only the start of movement of the movable member of the valve, corresponding only to the overcoming of mechanical clearances and dissipative and deformation effects internal to the actuator (1), and furthermore is such as not to substantially involve any alteration in the flow of fluid controlled by the valve. In this way, it is possible to estimate the state of health of the actuator device (1) without causing variations in the flow of fluid through the aforesaid valve.

An abnormality detecting system and an abnormality detecting method acquires a stroke of a piston as input from outside, calculates a travel time of the piston based on the results of sensing obtained by a first sensor and a second sensor, calculates a total travel distance of the piston using the number of operations and the stroke of the piston, and detects an abnormality of the actuator based on the travel time and the number of operations or the total travel distance of the piston.

A hydraulic lockout lever failure detection system preferably includes a first analog sensor, a second analog sensor, at least one electronic control module (ECU) and a solenoid valve. The voltage output level of the first and second analog sensors is monitored by the ECU. The solenoid valve controls the flow of hydraulic fluid to operate an excavator or other equipment. The operation of the solenoid valve is controlled by the ECU. However, a second ECU may be used to control the operation of the solenoid valve. A hydraulic lockout lever causes the first and second analog sensors to output either a low voltage to indicate a closed position, or to indicate an open position to the ECU. If the first and second analog sensors output a voltage that is above a low set value or above a high set value, a fault is detected.

A hydraulic drive system includes: a first hydraulic pump of the variable capacitance type; a first regulator including a first proportional valve; a second hydraulic pump that dispenses operating oil; a switch valve; a control device; and a malfunction detection device. The switch valve can switch to a third valve position in which the switch valve allows the operating oil dispensed from both the first hydraulic pump and the second hydraulic pump to be supplied to first and second traveling hydraulic motors and first and second hydraulic actuators. The control device controls the operation of the first proportional valve by outputting a first flow rate command signal to the first proportional valve, and when the malfunction detection device detects a malfunction of an electrical system related to the first proportional valve, the control device switches the switch valve to the third valve position.

A fluid module configured to be connected to an aircraft, comprising a manifold configured to direct fluid flow from an inlet to an outlet, the outlet configured to be connected to a hydraulic system of the aircraft and the inlet configured to be connected to a ground source of fluid, the manifold comprising a filter port adapted to receive a filter port; the first inlet in fluid communication with the filter port; and the outlet in fluid communication with the filter port. A method of utilizing the fluid module to provide fluid from the ground fluid source to the filter unit; filtering the fluid via the filter unit; and providing the filtered fluid from the outlet to one or more components, a reservoir of the aircraft, or combinations thereof.

A redundant valve manifold system includes at least two automatic valves coupled to one another and at least two automatic isolation valves each corresponding to one of the at least two automatic valves. Each of at least two automatic isolation valves is operatively coupled to one of the at least two automatic valves and isolates the one of the at least two automatic valves when the one of the at least two automatic valves is removed from the system to deliver media to an outlet.

A fluid leakage detection device includes: an annular member attached to a cylinder head, the annular member being configured such that a piston rod is inserted through the annular member; a passage formed in the annular member, the passage being configured such that a working fluid is guided to the passage from a gap between an outer circumference of the piston rod and an inner circumference of the cylinder head; and a detector configured to detect the working fluid guided through the passage, wherein the annular member includes a press-fitted portion, the press-fitted portion being configured to be press-fitted to an annular groove formed in the cylinder head.

A hydraulic drive system includes: a first hydraulic pump of the variable capacitance type; a first regulator including a first proportional valve; a second hydraulic pump that dispenses operating oil; a switch valve; a control device; and a malfunction detection device. The switch valve can switch to a third valve position in which the switch valve allows the operating oil dispensed from both the first hydraulic pump and the second hydraulic pump to be supplied to first and second traveling hydraulic motors and first and second hydraulic actuators. The control device controls the operation of the first proportional valve by outputting a first flow rate command signal to the first proportional valve, and when the malfunction detection device detects a malfunction of an electrical system related to the first proportional valve, the control device switches the switch valve to the third valve position.

Methods and apparatus for quantifying pneumatic volume usage via valve controllers are disclosed. An example apparatus includes a valve controller operatively couplable to a pneumatic actuator, the pneumatic actuator being operatively coupled to a control valve. In response to an input signal indicating that a flow control member of the control valve is to be moved in a specified direction, the valve controller commands a current-to-pressure (I/P) converter of the valve controller to pulse a relay valve of the valve controller between a closed position and an open position. The pulsing of the relay valve causes the pneumatic actuator to move the flow control member in the specified direction. The valve controller calculates a pneumatic volume usage associated with the moving of the flow control member in the specified direction. The pneumatic volume usage is based on the pulsing of the relay valve.