346 results about "Backflow prevention device" patented technology

A closed loop water purification system comprising a feed water line (42) to supply feed water, a high pressure feed pump (62), a filter assembly (66) having an inlet supplied by the high pressure feed pump, a distribution line (68) and a reject water line (70), the reject line returning reject water from the filter assembly to the feed water line, the distribution line supplying at least one purified water take off point (86) and returning to a junction (50) in the feed water line upstream of the high pressure feed pump. The reject water line is connected to the junction in the feed water line upstream of the high pressure feed pump. A first backflow prevention device (48) is on the feed water line upstream of the junction. A second backflow prevention device (100) is on the distribution line upstream of the junction and a third backflow prevention device (80) is on the reject water line upstream of the junction. A heater system (56) is in one of the distribution line, the reject line or the feed water line.

This disclosure provides a contactless power reception circuit that includes a power reception part, a voltage rectifying part, a voltage transforming part and a load modulation part. The voltage transforming part includes a smoothing capacitor, a DCDC converter and a backflow prevention device. The power reception part is couplable with an electromagnetic field adjacent to the contactless power reception circuit. The rectifying part rectifies a voltage output from the power reception part, the voltage transforming part transforms rectified voltage from the rectifying part, and the load modulation circuit conducts a load modulation while signals are transmitted. The smoothing capacitor smoothes a voltage input to the voltage transforming part, the DCDC converter transforms voltage smoothed by the smoothing capacitor, and the backflow prevention device prevents backflow of charge from the smoothing capacitor while the signals are transmitted to a contactless power transmission circuit.

A reduced pressure zone backflow preventer comprising a body 12 entirely made of plastic material, formed with an inlet port (14) accommodating an inlet check valve assembly 120 and an outlet port accommodating an outlet check valve assembly 122. The check valve assemblies extend along a coaxial axis coinciding with a longitudinal axis of the body. A central space 60 formed between the check valves is accessible through a service opening in the body. A relief valve assembly 70 is received within the central space and a drain port extends from the space. The relief assembly is responsive to pressure differential between the inlet port and the space by a flow passage extending between the inlet port and an upper side of a pressure diaphragm of the relief valve assembly.

The anti-back-flow devices and methods prevent fluid from leaking proximally from a catheter, but allow ready access to the catheter using any male luer device. The devices include proximal surfaces that urge open a valve in response to force from a male luer tip. The valves are associated a female luer hub and adapted to function with standard and typical non-standard male luer fittings.

A backflow prevention system that helps prevent contamination of potable water distribution systems from backflow at fire hydrant connections.

A water hydrant having a housing with inlet and outlet ends, and a valve assembly having a valve seat and a valve closure element. A valve operating rod is secured to the valve closure element to open and close the inlet end. A backflow preventor check valve mounted within the housing provides for fluid flow only in the downstream direction toward the outlet end. In one embodiment, the backflow preventor and valve closure element are formed of a unitary body; likewise, the valve seat and housing are formed of a unitary body. In another embodiment, an extension body is associated with the valve operating rod and the backflow preventor is attached to the extension body upstream from the valve seat. In a further embodiment, the backflow preventor is secured to the housing upstream from the valve seat, and is adapted to remain in a fixed position when the inlet valve is adjusted.

A back flow prevention device is shown for use in a plastic pipeline for conveying water, sewage, hydrocarbons or other fluids. A valve body features a flow control mechanism which is formed entirely or primarily of plastic materials. The valve body and its opposing ends are formed of a plastic material which is compatible with the plastic material of the existing pipeline, whereby the valve body can be installed in the pipeline in co-axially fashion by directly joining the opposing ends of the body to the opposing mating pipe ends at a selected location within the pipeline.

A backflow prevention device includes a main body holding a removable cartridge. The removable cartridge houses two independently acting check valves and, optionally, a relief valve. A first portion of the cartridge may be retracted into a second portion of the cartridge, thereby reducing the overall length of the cartridge and facilitating the removal of the cartridge from the main body without the need to remove the backflow prevention device from a water supply system. The relief valve is contained in a removable cartridge. Each check valve may have a self cleaning plunger bore comprising at least one spiral groove.

A backflow prevention device includes a main body holding a removable cartridge. The removable cartridge houses two independently acting check valves and, optionally, a relief valve. A first portion of the cartridge may be retracted into a second portion of the cartridge, thereby reducing the overall length of the cartridge and facilitating the removal of the cartridge from the main body without the need to remove the backflow prevention device from a water supply system. The relief valve is contained in a removable cartridge. Each check valve may have a self cleaning plunger bore comprising at least one spiral groove.

A backflow prevention device includes at least one backflow prevention unit. The backflow prevention unit includes a frame, a first edge shutter plate, a second edge shutter plate and plural intermediate shutter plates. The frame includes an airflow channel. If the first inner sidewall is disposed over the second inner sidewall, the first edge shutter plate and the plural intermediate shutter plates are configured to open or close the airflow channel, and the slab of the second edge shutter plate is inactive. Whereas, if the second inner sidewall is disposed over the first inner sidewall, the second edge shutter plate and the plural intermediate shutter plates are configured to open or close the airflow channel, and the slab of the first edge shutter plate is inactive.

The invention relates to a back-flow preventer used for controlling liquid of a micro-fluidic chip and the micro-fluidic chip thereof. The back-flow preventer comprises a micro-fluidic channel and a back-flow preventing structure, the back-flow preventing structure is positioned over the micro-fluidic channel and has a back-flow preventing channel; the back-flow preventing channel can lift the liquid level height of the micro-fluidic channel at the installation position of a back-flow preventing structure; when the micro-fluidic channel is connected with the air passage, under driving of air pressure provided by air passage, liquid level height pressure of the micro-fluidic channel which is lifted by the back-flow preventing channel is overcome, and the liquid in the micro-fluidic channel at two sides of the back-flow preventer is urged to a circulation state. The back-flow preventer has good back-flow preventing function.

An injection device for a light metal injection molding machine includes a melting device for melting light metal material into molten metal, plunger injection device for carrying out injection of molten metal using a plunger after the molten metal is metered into an injection cylinder from the melting device, connecting member including a connecting passage for connecting the melting device and the plunger injection device, and backflow prevention device for preventing backflow of molten metal by opening and closing the connecting passage.

Provided is an enclosure with an integrated hydrant. The enclosure includes a fluid flow conduit that transfers fluid from a fluid supply tube to a fluid outlet, which may be associated with the backflow preventer. The enclosure has a conduit that carries water from the fluid supply tube to the backflow preventer. Thus, a lower profile, lighter, and more aesthetically pleasing enclosure is provided.

An insertable backflow preventer is presented. The backflow preventer is provided with a cylindrical housing. The housing has a flow transition zone, a proximal orifice/ball seat, a ball with a specific weight that equals or is close to the specific weight of the surrounding fluid, and a distal retaining screen. The housing can have a flange provided on the outside of the housing at one end to facilitate securing the valve in a pipe. The valve is self-cleaning, can be placed in any orientation in a pipe and has low hydraulic head-loss. The valve's unique cost-effective design provides for easy and relative quick installation, eliminates the need to reconfigure existing plumbing, and can be performance tested remotely. Properly installed, it can dramatically improve the security of, for example, potable water sources in a building or other context, and inasmuch as when installed it is not visible, it is tamper proof. The valve can be scaled to any size pipe or tube, and due to its internal flow dynamics is self cleaning. Multiple valves can be installed in series, and balls of varying specific weight can be used in each valve in such a series to allow for contexts where a range of fluids are sent through the same line, or to provide fail-safe operation in the event that contaminants change the specific gravity of the fluid.

A backflow prevention device includes a plurality of flaps and a frame case for rotatably supporting the flaps. The flaps are opened by airflow supplied from a cooling fan and closed by gravity when the airflow stops. The backflow prevention device also includes a connecting member for connecting between the flaps. The connecting member serves to open the flaps at the same angle or close them simultaneously in response to changes in the amount of airflow supplied by a cooling fan in a manner such that the flaps are cooperatively opened or closed.

Provided is an air blowing unit for a vehicle which, even when a backflow prevention means which prevents the flow of air which flows back through a gap formed between a bottom surface of an impeller and an upper surface of a motor flange is adopted, optimally maintains a size of the gap thus suppressing noises and the collection of moisture and, can suitably boost a pressure of air in a scroll case portion.

With respect to a case of an air blowing unit, a projecting portion is formed in a projecting manner on an inner side of a second wall portion on a side opposite to a first wall portion where an air suction port is formed as an air backflow prevention means. The projecting portion is positioned outside an impeller in the radial direction with a predetermined gap between a radial outer end of the impeller and the projecting portion.

The invention relates to the technical field of dishwashers, in particular to a drainage system of a dishwasher. The drainage system of the dishwasher comprises a water cup, the water cup is providedwith a drainage port, the drainage port is connected with a drainage channel, the drainage channel is connected with a centrifugal impeller drainage pump, and a drainage pipe is arranged behind the drainage channel; a forced discharge port is formed nearby the lowest portion of an inner cavity formed by communicating the water cup with a drainage pump shell and connected with a forced discharge pipe, and the forced discharge pipe is further provided with a volumetric forced discharge pump and a residual water backflow prevention device such as a valve structure. The drainage system can completely drain residual water in the dishwasher and keep the dishwasher clean and hygienic.

An occlusion device for vascular surgery, suitable for clogging treatments of vascular entry sites and for endovascular interventions such as embolizations of blood vessels, treatment of arteriovenous malformations or small aneurysms, arterial dissections and the like, by releasing in an operation region a quick setting surgical glue or haemostatic fluid, through an outlet mouth of a duct. The device prevents the surgical glue from contacting within the duct a patient's biological fluids, in particular blood, which would close the duct. In the case of clogging treatments of vascular entry sites, a backflow preventing device may be provided, preferably provided by a coupling device between the duct and an introducer sheath by which an outlet mouth is kept in contact to keep in a one-way fluid tight contact against the outer surface of the introducer sheath until an injection pressure P2 is applied to cause release of the surgical glue.

A machine for removing sump pit water with sump ejector mounted at the same elevation as the discharge pipe, eliminating back pressure which reduces pumping rates, sump ejector system with an adjustable timing control allowing the pump to run for various lengths of time, a independent discharge line, sump ejector with an independent suction line, sump ejector with an internal check valve, sump ejector with an atmospheric vent preventing backflow, and sump ejector with integral backflow prevention device.

A backflow resistant stop valve for an aircraft galley plumbing system comprises a valve body defining an inlet, and inlet chamber, a transfer chamber, an outlet chamber, and an exit. The valve incorporates an anti-backflow device at the exit to prevent backflow, and flow through the body is controlled by a pivoting paddle disposed within the valve body having an upper flap, a spindle, and a lower flap, where the upper flap seals against the inlet chamber and the lower flap seals against the outlet chamber when the paddle is rotated to a first position. The valve utilizes a negative pressure at the outlet chamber that biases the valve closed until a sufficient column of water overcomes the bias.

An anti-backflow device includes a case and a plurality of flappers. The case has at least one opening and a plurality of combining portion. The combining portions are disposed in two opposite sides of the opening. The combining portions and the case are integrally formed. The flappers are disposed in the opening in sequence. Each flapper has a first connecting portion and a second connecting portion, each of which pivots on one of the combining portions.

An insertable backflow preventer is presented. The backflow preventer is provided with a cylindrical housing. The housing has a flow transition zone, a proximal orifice/ball seat, a ball with a specific weight that equals or is close to the specific weight of the surrounding fluid, and a distal retaining screen. The housing can have a flange provided on the outside of the housing at one end to facilitate securing the valve in a pipe. The valve is self-cleaning, can be placed in any orientation in a pipe and has low hydraulic head-loss. The valve's unique cost-effective design provides for easy and relative quick installation, eliminates the need to reconfigure existing plumbing, and can be performance tested remotely. Properly installed, it can dramatically improve the security of, for example, potable water sources in a building or other context, and inasmuch as when installed it is not visible, it is tamper proof. The valve can be scaled to any size pipe or tube, and due to its internal flow dynamics is self cleaning. Multiple valves can be installed in series, and balls of varying specific weight can be used in each valve in such a series to allow for contexts where a range of fluids are sent through the same line, or to provide fail-safe operation in the event that contaminants change the specific gravity of the fluid.

A multiple straw fluid dispenser is disclosed including a cap assembly containing two or more straws, each of the straws are accessible to one or more users for the purpose of drinking one or more fluids. Each straw includes a back flow prevention means allowing users to drink a fluid or fluids independent of other users and or other fluids. The fluid dispenser may be used in a conjunction with a multiple compartment fluid storage container or a single compartment storage container.