Abstract: The invention relates to a filter device for filtering a liquid, in particular, a hydraulic oil, comprising a filter housing having a least one inlet for liquid to be filtered and at least one outlet for filtered liquid, a filter element positioned in the flow path of the liquid between the inlet and the outlet, and a sealing device having a sealing element and a first sealing surface, the sealing element in a sealing position being positioned in a sealing manner on the first sealing surface. In order to further develop the filter device in such a way that the sealing element also lies reliably on the first sealing surface under alternating pressure loads, it is proposed, in accordance with the invention, that the filter device comprise a locking device, and the sealing element be adapted to be locked in its sealing position at least in the axial direction relative to the first sealing surface by means of the locking device. A filter element for the filter device is also proposed.

Abstract: The invention relates to a filter device for filtering a liquid, in particular, a hydraulic oil, comprising a filter housing having a least one inlet for liquid to be filtered and at least one outlet for filtered liquid, a filter element positioned in the flow path of the liquid between the inlet and the outlet, and a sealing device having a sealing element and a first sealing surface, the sealing element in a sealing position being positioned in a sealing manner on the first sealing surface. In order to further develop the filter device in such a way that the sealing element also lies reliably on the first sealing surface under alternating pressure loads, it is proposed, in accordance with the invention, that the filter device comprise a locking device, and the sealing element be adapted to be locked in its sealing position at least in the axial direction relative to the first sealing surface by means of the locking device. A filter element for the filter device is also proposed.

Abstract: The invention relates to a connecting device having a first pipe connecting piece, a second pipe connecting piece and a securing part. The two pipe connecting pieces are adapted to be connected to one another in a releasable and fluid-tight manner by the securing part. The first pipe connecting piece has at least one recess on the outside, and the second pipe connecting piece has a collar and an outer piece of pipe, which between them form an annular space bounded on one side in the axial direction and which accommodates a sealing element. The outer piece of pipe has at least one aperture. The first pipe connecting piece is adapted to be introduced into the annular space. The securing part has at least one catch element, which can be inserted into an aperture, thereby entering a recess. A filter device with such a connecting device is also provided.

Abstract: The invention relates to a filter element (50), in particular for a tank breather filter (10), the filter element (50) being produced from a flat filter material. To form the filter element (50) in such a way that it can be produced at low cost, it is proposed that it is made in one piece and has an end wall (51), which is surrounded by a corrugated side wall (52) aligned at an angle with respect to the end wall (51). A method for producing a filter element of this kind (50) and a tank breather filter (10) with a filter element of this kind (50) are also proposed.

Abstract: The invention relates to a filter device (10) for filtering a liquid, in particular a hydraulic oil, having a substantially cylindrical filter housing (12), which accommodates a filter element (30) and can be closed off by means of a cover (18), the filter element (30) having an associated untreated region (70) with an inlet (22) for supplying liquid which is to be filtered and a clean region (74) with an outlet (26) for removing filtered liquid, and the filter element (30) comprising an end plate (58) which is remote from the cover (18) and on which there is mounted a radially acting sealing element (62) for sealing the untreated region (70) of the filter element (30).

Abstract: The invention relates to a connecting means (36) having a first pipe connecting piece (32), a second pipe connecting piece (33) and a securing part (34), the two pipe connecting pieces (32, 33) being able to be connected to one another in a releasable and fluid-tight manner by means of the securing part (34).

Abstract: The invention relates to a filter element (50), in particular for a tank breather filter (10), the filter element (50) being produced from a flat filter material. To form the filter element (50) in such a way that it can be produced at low cost, it is proposed that it is made in one piece and has an end wall (51), which is surrounded by a corrugated side wall (52) aligned at an angle with respect to the end wall (51). A method for producing a filter element of this kind (50) and a tank breather filter (10) with a filter element of this kind (50) are also proposed.

Abstract: The invention relates to a filter element for fluids, in particular for hydraulic fluids, comprising a filter material and a grid-like supporting structure supporting the filter material at least on its outflow side in relation to the flow direction of the filter element. In order to further develop the filter element such that it has a high mechanical stability, whilst static charges are avoided, it is proposed in accordance with the invention that the supporting structure comprise elements made from a plastics material and electrically conductive elements.