A hatch mechanism for a pre-separator 120, the mechanism comprising an aperture having a perimeter arranged in a plane, and at least three elongated obturator elements pivotably attached along the perimeter at respective hinge ends, each obturator element comprising a distal end arranged opposite to the hinge end along the extension direction of the obturator element, wherein adjacent obturator elements arranged along the perimeter are connected by foldable joining members arranged to guide the distal ends to a common intersection point distanced from the plane, whereby the obturator elements are arranged to fold about respective hinge ends to a position of mutual support to close the hatch mechanism.

Specialized dust collection systems are provided that include a pulsed air system; at least one diaphragm valve assembly, which functions as the pulsed air valve; and a controller for controlling the diaphragm valve assembly and pulsed distribution of the pressurized air. The diaphragm valve assembly may be controlled by the controller and is operable to selectively deliver pressurized air to the air distribution assembly in short pulses or bursts. The disclosed diaphragm valve assembly can be utilized to improve the functionality of the pulsed air system and the dust collection system.

Included herein are filtration systems that can proactively pulse clean filter elements in response to anticipated changes, such as anticipated changes in filtration performance or anticipated changes in filtration system demand. In an embodiment, a filtration system is included having a filter element mount for a filter element, a compressed gas supply, and a valve, wherein opening the valve results in a pulse of gas directed at the filter element. A control circuit can control the valve. A communications circuit can receive data related to an anticipated change, such as data regarding an anticipated change in filtration performance and/or data regarding an anticipated change in filtration system demand. The control circuit can execute operations based on the anticipated change data such as adjusting a pressure drop threshold and initiating proactively opening the valve in the absence of a pressure drop threshold being crossed. Other embodiments are also included herein.

A respiratory filter and condensate management apparatus is provided for use in a breathing circuit during patient respiration. The apparatus includes a filter housing having an air inlet port and an air outlet port. A filter member is provided within the filter housing and located in an expiratory air flow path. A collection jar is removably attached to the filter housing and has a liquid reservoir to collect liquid formed by condensation in the flow of expiratory air within the filter housing when the collection jar is attached to the filter housing. A valve assembly moves to an open position when the filter housing is attached to the collection jar to allow drainage of the liquid from the filter housing. The valve assembly moves to a closed position when the filter housing is detached from the collection jar to prevent drainage of the liquid from the filter housing.

An apparatus to allow or stop a flow into an enclosed environment or piping system comprises: (a) a housing having an upper flow passage, a middle flow passage, a lower flow passage; (b) a first valve seat, wherein the first valve seat is between the upper flow passage and the middle flow passage, and wherein a first opening is formed on the first valve seat; (c) a first rotary valve inside the housing, moving inside the upper flow passage and above the first valve seat; (d) a second valve seat, wherein the second valve seat is between the middle flow passage and the lower flow passage, wherein a second opening is formed on the second valve seat; and (e) a second rotary valve inside the housing, moving inside the middle flow passage and above the second valve seat.

A vacuum cleaner including a suction inlet, a conduit in fluid communication with the suction inlet, a filter having a valve releasably connected to a filter inlet, the filter configured to collect debris drawn through the suction inlet. The vacuum cleaner further comprising a release mechanism moveable from a first position to a second position. In the first position, the filter is in fluid communication with the conduit to collect debris with the valve being open, and in the second position, the filter is disconnected from the conduit with the valve being closed. Movement of the release mechanism between the first and second positions closes the valve.

An apparatus which includes an aspirated smoke detector, and a pre-filter coupled to an inflow port of the detector wherein the pre-filter carries a removable filter element. The filter element is configured such that when it is removed, fluid flow through the filter is blocked. When the filter element is present in the pre-filter, fluid flow through the filter is permitted.

An air cleaner structure for blocking an inflow of debris to prevent the debris from inflowing into an engine intake passage of an air cleaner housing when replacing a filter includes a rotator fixing the filter and a filter cover to the air cleaner housing and generating a rotating force to open and close the engine intake passage. An engine intake passage door opens and closes the engine intake passage by the rotating force of the rotator. A connector has one end connected to the rotator and another end connected to the engine intake passage door to deliver the rotating force to the engine intake passage door.

An air cleaner may include a filter case configured to introduce, by a suction force of an internal space, ambient air being discharged through a filter provided in the internal space as intake air from which foreign substances are removed; and a built-in valve built in the internal space of the filter case and configured to form an ambient air introduction path for introducing the ambient air and an additional ambient air introduction path separated from the ambient air introduction path and to open the additional ambient air introduction path so that the ambient air flows into through the additional ambient air introduction path when the suction force is increased.

An adsorbed natural gas storing tank is provided. The adsorbed natural gas storing tank includes a tank body that has an upper plate and a lower plate coupled to define an inner space provided with an adsorbent material. The tank body includes an opening that extends through the upper and lower plates. A central plate is inserted in the opening to seal one side of the tank body. Additionally, the central plate has a plurality of discharge apertures formed along a circumferential wall thereof to discharge natural gas reacted with the adsorbent material and has a mounting region therein. A filter assembly is inserted in the mounting region, is fastened to the central plate, filters natural gas passing through the discharge apertures, and is equipped with a control valve for adjusting natural gas discharge.