Abstract: A backflow valve for an end of a pipe includes a cylindrical body having coupling at a first end which is adapted to mate with an end of a pipe. A closure gate is pivotally mounted to the second end of the body for movement about a substantially horizontal axis between an open position permitting flow in one direction through the flow passage and a closed position blocking the flow passage to prevent a reversal of flow.

Abstract: A backflow valve has a closure gate that is pivotally mounted for movement between an open position in which the closure gate is positioned on a plane substantially parallel to a longitudinal axis of a flow passage and a closed position in which the closure gate is positioned transverse to the longitudinal axis. The closure gate has a midsection positioned pivot axis and is unbalanced with greater weight being toward the first end. A rotational stop limits pivotal movement when the closure gate is in the open position. A float is secured to the first end of the closure gate. The greater weight at the first end biases the closure gate by force of gravity against the rotational stop and into the open position. The float causes the closure gate to pivotally move to the closed position in response to liquid rising in the flow passage.

Abstract: A device for feeding fuel from a supply container to an internal combustion engine of a motor vehicle has a supply container, a collecting cup arranged in the supply container, a fuel feeding pump which aspirates fuel from the collecting cup, a feeding conduit into which the aspirated fuel is fed to the internal combustion engine, a return conduit through which a fuel is returned back to said supply container, a jet pump arranged in the supply container and having a jet nozzle connected with the return conduit, a mixing pipe which is open in the collecting cup and is substantially in alignment with the jet nozzle, a suction opening provided between the jet nozzle and the mixing pipe, a check valve flap arranged in the collecting cup and closing an outlet of the mixing pipe, the check valve flap being formed so that it deviates a filling jet of the jet pump which is supplied from fuel from the supply container into the suction cup against a fuel pressure in the suction cup, from the outlet of the mixing pipe.

Abstract: A scroll compressor has a check valve plate assembly with a reinforcing device to increase the strength of the check valve plate. The check valve plate is stamped from a relatively thin steel reed material. Notched areas are provided during stamping to enable the formation of rolled laterally spaced pins which provide an axis along which the check valve plate may pivot. The reinforcing device is in the form of a slot rolled pin, a spiral rolled pin, or a solid pin, fitted within a bore formed by the rolled laterally spaced pins of the check valve plate. The notched areas of the check valve plate are weakened due to the reduction of the local cross sectional area of the laterally spaced pins. Insertion of the reinforcing device significantly reduces the incidence of cracking that occurs at the notched areas of the check valve plate.

Abstract: A double check valve backflow prevention apparatus of lightweight modular construction. The apparatus comprises a primary housing component having a flangeless lateral opening, a first check valve module which fits within the lateral opening a second check valve module which also fits within the lateral opening a central housing component, with the central housing fitting within the lateral opening between the first check valve module and second check valve module. A first fluid tight seal is positioned between the first check valve module and central housing component, and a second fluid tight seal is positioned between the second check valve module and central housing component. A third fluid tight seal is positioned between the first check valve module and the primary housing component, and a fourth fluid tight seal is positioned between the second check valve module and the primary housing component.

Abstract: The invention is a bi-directional cleanout for pipelines such as sewer pipelines and a bi-directional cleanout with a built in backflow preventer. The backflow preventer is a check valve which allows fluid to flow in one direction, but not in the other direction. The bi-directional cleanout is a device which has a single access point at ground level, is located outside a house typically, and which directs a cleanout tool down one of two tool guide tubes. The guide tubes direct the cleanout tool into one of two tool guides which deflect the cleanout tool and cause it to enter the pipeline to be cleaned in a direction towards one or the other of the ends. The check valve is insertable into the pipe level unit in which the tool guides are located. While the pipeline is being cleaned out with the cleanout tool, the check valve can be removed and reinserted after the cleanout procedure is completed.

Abstract: It comprises a body provided with an inlet and an outlet; a moving gate which separates said inlet and said outlet; a seat formed on said body and adapted for said gate to rest against it; hinge means of the gate to the body of the valve; and means for keeping the gate in position against the seat, the latter comprising a body attached to one end of the gate, the gate and said body being hinged to the valve body in such a way that both can rotate around a single hinge pin, which is arranged eccentrically with respect to said body attached to the gate, so that the gate is kept in equilibrium when the pressure inside the valve exceeds 0.1 bar. The pin is aligned with the point of contact between the gate and the seat of the valve body and is detachable.

Abstract: A check valve device for a scroll machine is used to automatically maintain a unique flow direction of the working media. The check device is mounted on the neck of the non-orbiting scroll member of the scroll machine, in which the neck has an axle hole for defining a first passage for flowing the working media. The check valve includes a housing and a valve member. The housing has a through second passage, and couple with the neck in such a manner that a through passage is formed for connecting the first passage of the neck and the second passage of the housing. The valve member is located inside the second passage of the housing, and is formed as a plate with a pivot means to rotate along. While the scroll machine is in stop operation, the valve member is at a close position that the valve member can substantially block the flow of the working media inside the second passage.