A pocket filter assembly with reduced risk for exposing a user to contaminations leaving the pocket filter assembly during and after removal of the pocket filter assembly from an installation is disclosed. A first pocket filter comprises a grip member configured to be gripped by the user to enable folding of the pocket filters in a controlled manner before removal of the pocket filter assembly from an installation.

A filter device for filtering particles from an air stream has an inlet channel through which the air to be purified flows, at least one filter element through which the air can flow and which is interchangeably held in a flow channel, and an outlet channel through which the purified air flows, an insertion chamber which can be closed by a door and from which a filter element can be fed to the flow channel, and an output chamber closable by a closure element, into which a filter element is feedable from the flow channel. The closure element of the output chamber is locked in the closed position via a locking mechanism when the door on the insertion chamber is opened and the output chamber and the insertion chamber are connected to the same flow channel.

A filter device for filtering particles from an air flow has an inlet channel through which the air to be cleaned flows, at least one filter element through which the air can flow and which is held replaceably in a flow channel, and an outlet channel through which the cleaned air flows. The filter device has an insertion chamber which can be closed by a door and from which a filter element can be fed to the flow channel, and an output chamber which can be closed by a closure element and into which a filter element can be fed from the flow channel. A cover is attachable to the filter element, which covers a filter cake on the filter element so that the unit of filter element and cover is removable from the output chamber together.

Fume extraction device, in particular laboratory fume extraction device, including a housing with an operating chamber that is accessible to an operator through an operating hole in the housing; the operating chamber is defined by a base, side walls and a cover; the operating hole and/or at least one fresh air supply hole in the area of the operating hole is/are provided for allowing fresh air to flow into the operating chamber, and at least one waste air hole in the area of the cover is provided for allowing waste air to escape. At least one filter holder for accommodating at least one filter element is placed upstream of the at least one waste air hole; the at least one filter holder is accessible through the operating hole such that the filter element is accessible and replaceable from the operating chamber.

This invention concerns an additive manufacturing apparatus for building a part by selectively consolidating flowable material in a layer-by-layer process comprising a build chamber (101) for building the part, a module (105, 106) for providing a focussed energy beam for consolidating flowable material in the build chamber, a gas flow circuit for generating a gas flow through the build chamber (101). At least one filter assembly (200, 201) may be arranged in the gas flow circuit, the or each filter assembly (200, 201) having associated therewith a valve (V-4, V-8) operable to seal the gas circuit upstream from the filter assembly (200, 201) and a valve (V-5, V-9) operable to seal the gas flow circuit downstream of the filter assembly (200, 201), the arrangement allowing a filter element (E-5, E-7) of the filter assembly (200, 201) to be changed whilst maintaining a controlled atmosphere in the build chamber (101). The apparatus may further comprise a purging device (210) configured to purge air from the or each filter assembly (200, 201) when the valves (V-4, V-5; V-8, V-9) associated with that filter assembly (200, 201) have sealed the filter assembly (200, 201) from the gas flow. Alternatively or additionally, a controller (131) may be arranged to control the valves (V-4, V-5; V-8, V-9) associated with the or each filter assembly (200, 201) such that the filter assemblies (200, 201) are closed off to gas flow from the build chamber (101) during a period in which the inert gas atmosphere in the build chamber (101) is compromised as a result of opening the door to the build chamber (101). The apparatus may comprise a pair of filter assemblies (200, 201) arranged in parallel within the gas flow circuit, the arrangement allowing a filter element (E-5, E-7) of the each filter assembly (200, 201) to be changed during a build by allowing the filter element (E-5, E-7) of one filter assembly (200, 201) to be changed whilst the filter element (E-5, E-7) of the other filter assembly (200, 201) is connected to filter particulates from the gas flow. A monitoring device (I-3, I-5) may be provided for detecting a property associated with the gas flow and a controller (131) arranged to control the valves to switch the filter assembly (200, 201) connected in line with the gas flow based upon signals from the monitoring device (I-3, I-5