A spool is slidably located in a slide hole of a first housing. A second housing forms a servo chamber that is coaxial with the slide hole. A sleeve is slidably located in the servo chamber. A nut is fixed to a piston that is slidably fitted in the sleeve. An electric motor rotates a screw shaft screwed with the nut. The second housing includes an input port and a drain port. A first pressure chamber communicates with the input port. In a balanced state where forces applied to the sleeve from both sides are balanced, a second pressure chamber is blocked from the input port and the drain port by the piston. From the balanced state, when the piston shifts, the second pressure chamber comes into communication with the input port or the drain port.

[Problem] To provide a valve system capable of monitoring in real time a mass of gas supplied from a valve that is periodically opened and closed, and that is capable of adjusting the output mass of gas supplied from the valve to be close to a target mass.

[Solution] The valve system operates a main actuator 60 to make a diaphragm periodically open and close a flow path (step S2), calculate an output mass of fluid that passes through the a between the diaphragm and a valve seat and output from the diaphragm valve based on displacement data detected by a displacement sensor (step S3), determines an adjustment lift amount based on the calculated output mass, and adjusts a lift amount Lf of the diaphragm 20 by the determined adjustment lift amount (step S4).

A servovalve system comprising a pilot stage valve in communication with an hydraulic stage valve, the hydraulic stage valve comprising a valve member movably mounted in a valve chamber to selectively meter fluid flow in a flow path from an upstream inlet port to a downstream outlet port and at least two variable-sized orifices disposed in the flow path between the inlet and outlet ports, an upstream pressure sensor, a downstream pressure sensor, a fluid temperature sensor, a position sensor sensing a linear position of the valve member, a controller that receives input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor; and the controller configured to provide a control signal to the pilot stage valve as a function of the input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor.

A servovalve system comprising a pilot stage valve in communication with an hydraulic stage valve, the hydraulic stage valve comprising a valve member movably mounted in a valve chamber to selectively meter fluid flow in a flow path from an upstream inlet port to a downstream outlet port and at least two variable-sized orifices disposed in the flow path between the inlet and outlet ports, an upstream pressure sensor, a downstream pressure sensor, a fluid temperature sensor, a position sensor sensing a linear position of the valve member, a controller that receives input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor; and the controller configured to provide a control signal to the pilot stage valve as a function of the input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor.

A pressure support device such as a CPAP machine, is provided, which includes a housing, and a controller enclosed by the housing. The controller operates the CPAP machine independently or in combination with an accessory such as, for example and without limitation, a humidifier. A user interface is operably coupled to the controller and includes a primary display, a secondary display and a single control. The single control is operable in a first mode of operation to adjust operating parameters of the CPAP machine, and in a second mode of operation to adjust operating parameters of the humidifier. The secondary display preferably comprises a dead front, which is operational (e.g., without limitation, visible) only in the second mode of operation. A method of operating a pressure support device is also disclosed.

A pump includes a vibrating plate, a flow path forming member, a pump chamber, and a film valve. The vibrating plate is provided with a piezoelectric element, vibrates due to distortion of the piezoelectric element, and has a gap on an outer periphery. The flow path forming member is disposed so as to face the vibrating plate, and has a hole in a portion facing the vibrating plate. The pump chamber is surrounded by the vibrating plate and the flow path forming member, and has a central space communicating with the hole and an outer edge space communicating with the gap. The film valve is disposed in the pump chamber. The film valve is in contact with the vibrating plate and the flow path forming member when a pressure in the central space is lower than a pressure in the outer edge space.

A fuel valve for regulating a flow of fuel to a combustion appliance includes a control module configured to determine fuel consumption based on a measure related to fuel flow through the fuel valve. The measure related to fuel flow through the valve may be determined using a known relationship between firing rate and the flow rate of fuel through the valve. Measurement accuracy may be enhanced by correcting for the excess air ration (also referred to as lamda).

Methods, systems, and apparatus, including computer programs encoded on a storage device, for detecting water leaks and mitigating the damage caused by the detected leaks. The system may include a processor and a storage device storing instructions that, when executed by the processor, cause the processor to perform operations. The operations may include obtaining sensor data that is generated by one or more flow rate sensors located at a property, obtaining status data that is generated by one or more connected water shutoff valves located at the property, determining, based on (i) the obtained sensor data and (ii) the obtained status data whether a water leak has been detected at the property, and in response to determining, based on (i) the obtained sensor data and (ii) the obtained status data, that a water leak has been detected at the property, initiating performance of one or more water damage mitigation operations.

Methods, systems, and apparatus, including computer programs encoded on a storage device, for detecting water leaks and mitigating the damage caused by the detected leaks. The system may include a processor and a storage device storing instructions that, when executed by the processor, cause the processor to perform operations. The operations may include obtaining sensor data that is generated by one or more flow rate sensors located at a property, obtaining status data that is generated by one or more connected water shutoff valves located at the property, determining, based on (i) the obtained sensor data and (ii) the obtained status data whether a water leak has been detected at the property, and in response to determining, based on (i) the obtained sensor data and (ii) the obtained status data, that a water leak has been detected at the property, initiating performance of one or more water damage mitigation operations.

Proactive methods and articles of manufacture are disclosed for preventing any water leak or flooding of a toilet. These methods and systems can replace or be added to the water system of existing toilets, especially the North American toilets, which use water tanks. In various embodiments the water is turned OFF and prevented to enter the toilet tank before the flush handle is activated and/or before a user is sensed. In some embodiments each flushing of the toilet permits the toilet tank to only fill once. If a leak causes the tank to empty, water is not permitted to fill the leaking tank until the next time the flush handle is activated. In some other embodiments each flushing of the toilet and/or sensing of a user permits the toilet tank to fill a predetermined number of times.