Abstract: The invention relates to a filter device for filtering a hydraulic fluid comprising a housing having fluid through-openings for hydraulic fluid to be filtered to flow into the housing and for filtered hydraulic fluid to flow out of the housing, and having an assembly opening for inserting a filter element into the housing, the assembly opening being closable by a cover. In order to further develop the filter device such that it can be selectively configured in a cost-effective manner as a suction filter, return filter or return-suction filter, it is proposed in accordance with the invention that different filter elements be insertable into the housing, and that different functional modules be insertable into the housing or connectable to the housing.

Abstract: A filter device for filtering hydraulic liquid is provided, which has a housing having a housing upper part and a housing lower part. The housing upper part has a housing inlet and a housing outlet. A filter element is arranged in the housing lower part. The filter element has a dirty side in communication with the housing inlet and a clean side in communication with the housing outlet. The housing upper part comprises a convexly curved interior wall. An insertable flow-guiding element is arranged in the housing upper part which divides the housing upper part into a dirty region and a clean region. The dirty region is in communication with the dirty side of the filter element and the housing inlet opens into the dirty region. The clean region is in communication with the clean side of the filter element and the housing outlet leads out of the clean region.

Abstract: The invention relates to a filter device for filtering a hydraulic fluid comprising a housing having fluid through-openings for hydraulic fluid to be filtered to flow into the housing and for filtered hydraulic fluid to flow out of the housing, and having an assembly opening for inserting a filter element into the housing, the assembly opening being closable by a cover. In order to further develop the filter device such that it can be selectively configured in a cost-effective manner as suction filter, return filter or return-suction filter, it is proposed in accordance with the invention that different filter elements be insertable into the housing, and that different functional modules be insertable into the housing or connectable to the housing.

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: A filter element (10) having a supporting body (11) around which a filter medium (12) is wound. The filter medium (12) is a weldable material and is sealingly affixed to the supporting body (11) two radial weld seams (18) and/or a longitudinal weld seam (19). The welding of the filter medium (12) onto the supporting body (11) eliminates the need to produce prefabricated tubes of filter medium, and enables the filter medium to be processed directly from a roll.

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: A filter element (10) having a supporting body (11) around which a filter medium (12) is wound. The filter medium (12) is a weldable material and is sealingly affixed to the supporting body (11) two radial weld seams (18) and/or a longitudinal weld seam (19). The welding of the filter medium (12) onto the supporting body (11) eliminates the need to produce prefabricated tubes of filter medium, and enables the filter medium to be processed directly from a roll.

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: A method of making an air filter insert for cleaning the combustion air of an internal combustion engine. The method includes producing the filter insert (21) from a pleated filter medium (33) which is formed into a hollow cylinder, in which at least one end plate (33, 34) made of thermoplastic elastomer or thermoplastic polyurethane is disposed on the axial end faces of the filter medium (33). The at least one end plate (33, 34) is bonded to the cylindrical filter medium (33) by heating the filter medium or the end plate (33, 34) with a high-temperature heating element and fusing the filter medium (33) and the end plate (33, 34) to form a welded joint.

Abstract: A housing, in particular a pot-shaped filter housing. To connect housing pot 10 and cover 11, a joint consisting of closure elements such as locking clamps or bow clamps 16 is proposed which can be attached at the periphery of the housing via receivers 18. As there are more receivers 18 provided on the housing than locking clamps 16 which are required for absorbing retention forces, it is possible to vary the exact fitting position of the locking clamps according to the respective space available for receiving and mounting the housing. This is essential, because the rotating radius 27 of the tension levers 17 of the locking clamps has to be considered when mounting the locking clamps 16. It is thus possible to provide housings for any field of use with variable receivers for the closure elements.

Abstract: A mixing device is suggested for introducing a fluid into another flowing liquid, especially for use as an oil lubricator. This lubricator consists of an exterior venturi pipe 18 and an interior venturi pipe 16, whereby a feed line 13 ensures the supply of the oil to be mixed into the interior venturi pipe 16. The feed line 13 is connected to the storage tank 28 of the lubricator by means of a butterfly valve 30 and a uptake 29. A control insert 20 is mounted in the ring-shaped cross-section between the interior pipe 16 and the flow channel 18. This has elastic blades in particular, which largely close the circular ring section at lower amounts of throughput of the air, such that even in this operational state, consistently good mixing results of the oil with the air can be guaranteed in interior pipe 16.

Abstract: An air filter element, in particular for the cleaning of combustion air for internal combustion engines, in air filters with a substantially cylindrical, air-permeable housing. The air filter element has a raw air inlet area (2) and a clean air outlet area (3). The clean air outlet area is arranged substantially concentrically on one of the end surfaces of the cylindrical housing (1), and the raw air inlet area occurs substantially across the surface of the housing (1). An air-permeable center tube (4) connecting to the clean air outlet area extends inside the housing (1), and a substantially metal-free filter insert (5) is slid over the center tube (4) and separates the clean air from the raw air side. The opposite end surface (7) of the insert is sealed, and the clean air outlet side of the housing (1) has an axial seal (8) on the face thereof, it being possible to divide the housing (1).

Abstract: An air filter, especially for cleaning combustion air for internal combustion engines. The air filter includes a substantially cylindrical housing having a raw inlet and a pure air outlet. A pure air outlet is fitted substantially concentrically on the face of a cylindrical housing. The raw air inlet is fitted on the surface of the housing jacket, and an essentially menthol-free filter element is secured in the housing. The housing aperture is fitted with adaptive systems having an integrated dirt extractor.

Abstract: A filter, particularly for the filtering of the air for a vehicle interior, which includes a filter housing with a clean-air-side basic body, a filter insert, and an unfiltered-air-side cover. The filter insert is arranged between the basic body and the cover. The cover is provided with clamping elements which fix the filter insert in place.

Abstract: An indicating apparatus for indicating a vacuum, particularly for indicating the vacuum on the filtered-air side of an air filter for an internal-combustion engine, including a housing and a piston which is movably disposed in the housing and which separates a vacuum area from an anbient-pressure area. A snap element is provided which is activated by the piston and, at a predetermined vacuum, triggers an electric contact.

Abstract: An air filter, in particular for cleaning the combustion air for internal combustion engines, having a cylindrical housing provided with an unfiltered air inlet and with a clean air outlet mounted substantially concentrically on one of the axial end faces of the housing. An extension tube, which extends into the housing, is provided at the clean air outlet; a center tube, which extends into the housing, is secured to the inner wall of the extension tube, and a metal-free filter insert is slid onto the center tube. The filter insert has a radial packing on its end face which faces the extension tube, and the opposite end face of the insert is closed. The radial packing is provided with a sealing bead which is freely movable in the radial direction. A metal-free safety cartridge optionally may be arranged inside the center tube.

Abstract: A system for measuring the content of foreign substances in a gas stream, for example oil in a stream of compressed air. The system includes at least one probe for collecting a given amount of gas. In the probe there is at least one sensor over which the sampled gas is passed. For optimum evaluation and for signaling certain states of operation, the sensor includes a temperature sensor for determining the temperature of the gas sample flowing past it, and a detector whose electrical resistivity or conductivity depends on the nature and density of the foreign substances in the gas. The output signal of the detector corresponds to the concentration of foreign substance in the gas stream, and is processed in an electronic evaluation unit.