A filtration assembly structured to filter reductant includes an outer housing and an inner housing. The inner housing is positioned within the outer housing. The inner housing is structured to contain the reductant and operable between a first state in which the inner housing has a first volume and a second state in which the inner housing has a second volume that is larger than the first volume, the inner housing including an end face. The inner housing is separated from the outer housing by a gap when the inner housing is in the first state. A volume of the gap decreases as the inner housing transitions from the first state to the second state and increases as the inner housing transitions from the second state to the first state.

A filter element for filtering a fluid has a first filter medium arranged in annular shape and surrounding an interior. A second filter medium is provided, wherein the first filter medium and the second filter medium separate a clean side of the filter element from a raw side of the filter element. The first filter medium and the second filter medium are arranged such that a fluid to be filtered flows from the raw side of the filter element to the clean side of the filter element in parallel through the first filter medium and the second filter medium. The first filter medium is liquid-permeable and gas-impermeable and the second filter medium is liquid-impermeable and gas-permeable.

A filtration assembly structured to filter reductant includes an outer housing and an inner housing. The inner housing is positioned within the outer housing. The inner housing is structured to contain the reductant and operable between a first state in which the inner housing has a first volume and a second state in which the inner housing has a second volume that is larger than the first volume, the inner housing including an end face. The inner housing is separated from the outer housing by a gap when the inner housing is in the first state. A volume of the gap decreases as the inner housing transitions from the first state to the second state and increases as the inner housing transitions from the second state to the first state.

A filter device for filtering fluid particularly an aqueous urea solution, includes a filter housing (1), a filter element (11) and a compensating element (31) for compensating fluctuations in the pressure and/or volume of the fluid. At least one elastically-flexible membrane (31) serves as the compensating element. The membrane wall of of the membrane is held in a retaining part (35) and maintains a separation between the fluid and a compressible filling medium such as a working gas.

A freezing resistant liquid filter including a housing having a liquid inlet and a liquid outlet and a freezing compensating filter element disposed within the housing and including a folded filter medium having a plurality of interstices and freezing compressible elements located at the interstices.

The invention relates to a filter device (1) for filtering liquids, comprising: a filter element (2) having an interior (3) for accommodating a liquid, and a compensating element (5) made of elastically deformable material for accommodating a liquid volume that increases when the liquid freezes. The compensating element (5) is arranged in the interior (3), and a gap (6), in particular an annular gap, for accommodating the liquid is formed between the compensating element (5) and the filter element (3).

A filter for an aqueous solution, such as urea, of a diesel vehicle selective catalytic reduction system, includes a housing provided with an inlet and with an outlet and, inside which, is arranged a filter element. Variations in volume associated with changes in phase of the aqueous solution are detected and a switch which switches upon changes in phase of the aqueous solution signals the variations in volume.

The invention relates to a filter device for filtering fluid particularly in the form of an aqueous urea solution, comprising a filter housing (1) and a filter element (11) arranged therein, as well as a compensating element (31) for compensating fluctuations in the pressure and/or volume of the fluid, and characterised in that at least one elastically-flexible membrane (31) serves as the compensating element, the membrane wall of which is held in a retaining part (35) and maintains a separation between the fluid and a compressible filling medium such as a working gas.

Eine Filtervorrichtung zum Filtern von Fluid, insbesondere in Form einer wssrigen Harnstofflsung, mit einem Filtergehuse (1) und einem darin angeordneten Filterelement (11) sowie einem Ausgleichselement (31) zum Kompensieren von Druck- und/oder Volumenschwankungen des Fluids, ist dadurch gekennzeichnet, dass als Ausgleichselement mindestens eine elastisch nachgiebige Membran (31) eingesetzt ist, deren Membranwand in einem Halteteil (35) gehalten eine Trennung zwischen dem Fluid und einem kompressiblen Befllmedium, wic einem Arbeitsgas, vornimmt.

A filter device includes a filter element (3), through which a fluid to be purified can flow at a determinable fluid operating pressure, and which can be accommodated in a housing (1). The fluid pressure prevailing at the respective filter element (3) may exhibit pressure increases or pressure peaks, which are damaging to the filter element (3), and in particular to its filter material (9), and which can be reduced and/or smoothened by a compensation device acting directly on the filter element (3) and having a flexible compensation element (29) that enables the volume of the fluid chamber of the housing (1) to be increased in accordance with a pressure peak or pressure increase. The flexible compensation element (29) is arranged between the outer side of the filter material (9) of the filter element (3) and the adjacent inner wall of the housing (1).

A pipeline strainer having a body with a straining element therein. The body has a Y-shape and defines a cavity to receive the straining element. The cavity may be defined in part by a recess that comprises a surface which may be used to guide the straining element as it is inserted into the cavity. The recess may form a dome. The recess, when viewed cross sectionally, may have a linear segment and a curvilinear segment. A rounded protrusion may be created on an outer surface of the body as a result of the recess.