A method and apparatus for a vehicle suspension system gas spring. In one embodiment, a vehicle suspension system gas spring includes a compressible main gas chamber and an additional volume combinable with the main chamber to change a gas spring rate of the system. In one embodiment, a low friction piston seal is created by a flexible seal member.

A method and apparatus for a vehicle suspension system gas spring. In one embodiment, a vehicle suspension system gas spring includes a compressible main gas chamber and an additional volume combinable with the main chamber to change a gas spring rate of the system. In one embodiment, a low friction piston seal is created by a flexible seal member.

A method and apparatus for a vehicle suspension system gas spring. In one embodiment, a vehicle suspension system gas spring includes a compressible main gas chamber and an additional volume combinable with the main chamber to change a gas spring rate of the system. In one embodiment, a low friction piston seal is created by a flexible seal member.

A manifold having a first side, a second side, a first channel extending from the first side to the second side, and a second channel extending from the first side to the second side is disclosed. The first channel and the second channel each define a linear longitudinal axis. In one embodiment, the first channel longitudinal axis and the second channel longitudinal axis are oblique to the first side and the second side of the manifold. The manifold of the present disclosure provides channels that can be easily cleaned and allow for an increased flow performance.

A manifold having a first side, a second side, a first channel extending from the first side to the second side, and a second channel extending from the first side to the second side is disclosed. The first channel and the second channel each define a linear longitudinal axis. In one embodiment, the first channel longitudinal axis and the second channel longitudinal axis are oblique to the first side and the second side of the manifold. The manifold of the present disclosure provides channels that can be easily cleaned and allow for an increased flow performance.

A circulating hot water system has a hot water flow circuit defined by pipework leading out from and back to an in-line heater, and including a pump to drive circulation of the hot water. Each of multiple user points has an outflow branch conduit and a return flow branch conduit with a common wall for heat exchange, as does the main flow circuit: the outflow conduit surrounds the return conduit. Water is fed into the system from a pressurized cold water supply main through a check valve. Sensors are used to monitor water temperatures and flow conditions around the system. A programmed control processor can control heating and pumping rates in various regimes, e.g. to maintain system temperature above a predetermined threshold. An isolation valve adapted for concentric double pipes is also described.

A pinch valve may use a spring force to close a collapsible tube at a pinch point, and may open with a cam mechanism, which may be controlled using an electric motor. The open and closed positions of the pinch valve may be stable without the use of continuing electrical energy, and electrical energy may be consumed during a change between positions. One arrangement may use multiple tubes in a circular arrangement with a cam that may operate one or more of the valves at a time. The cam mechanism may be driven by an electric motor.

A device for mixing and metering of at least two gases, comprising two bodies that can be displaced relative to each other, wherein margins of the bodies are in contact with one another and between these margins at least two rectangular openings for one gas each can be formed, wherein a displacement of the bodies relative to each other automatically causes an increase of one opening and a decrease of the other opening, wherein the resulting total cross-section of the openings remains constantly the same here. Moreover, the device comprises a control element which is arranged adjacent to the two bodies and in contact therewith, wherein the control element can be translationally displaced in a continuous manner between a closed position and an open position in order to close or to open the openings.

A dual fuel heating system can be used in a gas appliance. A dual fuel heating system can have a fuel selector valve for selecting between a first fuel and a second fuel different from the first. The dual fuel heating system can include a regulator unit configured to regulate the pressure of the two different fuels. The selector valve determines which flow path for which fuel is open and which is closed.

A method and apparatus for a vehicle suspension system gas spring. In one embodiment, a vehicle suspension system gas spring includes a compressible main gas chamber and an additional volume combinable with the main chamber to change a gas spring rate of the system. In one embodiment, a low friction piston seal is created by a flexible seal member.