Abstract: An adjustable camshaft for a valve train of an internal combustion engine may include an inner shaft that is rotatable in an outer shaft, a phase shifter by which the outer shaft and/or the inner shaft are/is adjustable in a phase position formed around an axis of rotation, and a bearing portion for bearing the camshaft, via which the phase shifter can be supplied with a pressurizing medium. The inner shaft may comprise an end on which a screw flange is arranged, and a rotor of the phase shifter may be connected to the screw flange. A free end of the inner shaft comprises a duct that coincides with the axis of rotation for at least partially supplying the phase shifter with a pressurizing medium. The duct may extend at least into the bearing portion.

Abstract: A method concerns producing a cam profile of a cam pack with at least two cam elements that can be adjusted relative to each other. The camshaft may comprise an outer shaft, a rotatable inner shaft, a fixed cam element connected to the outer shaft, and an adjustment cam element connected to the inner shaft. The method may comprise processing an adjustment cam contour by a continuous diameter reduction of a segment of the adjustment cam base circle, wherein the adjustment cam base circle is reduced to a diameter that is smaller than a fixed cam nominal circle diameter minus a doubled adjustment cam base circle tolerance. The method may comprise processing a fixed cam contour by reducing a fixed cam contour protrusion in a region between a transition point and a processing point. Upon reaching the transition point a tapping element for converting a revolving motion of the cam elements into a linear motion of the valves is transferred from the fixed cam element to the adjustment cam element.

Abstract: The invention relates to a camshaft, especially for motor vehicle engines, comprising a hollow outer shaft (1) and an inner shaft (2) arranged coaxially in the outer shaft (1) and mounted in such a way that it can rotate in relation to the outer shaft (1). Said camshaft also comprises first cams (3a) arranged on the outer shaft (1) in a rotationally fixed manner, and second cams (3b) that are arranged on the outer shaft (1) and fixed to the inner shaft (2). According to the invention, a supporting element (7) is provided on at least one of the end regions of the inner shaft (2), said supporting element projecting past the outer shaft (1) in the radial direction. An outer peripheral surface (8) of the outer shaft (1) and an associated inwardly facing surface (9) of the supporting element (7) form a radial bearing.

Abstract: A camshaft for a valve drive of an internal combustion engine having a variable valve opening time may include an outer shaft and an inner shaft that extends through the outer shaft, with the inner shaft being held rotatably with respect to the outer shaft. The camshaft may further include a cam having a multiple-piece configuration, comprising a first part cam and a second part cam. Either the first part cam or the second part cam may be connected fixedly to the outer shaft so as to rotate with it, and the other part cam may be connected fixedly to the inner shaft so as to rotate with it. The camshaft may also include a bearing inner ring of a shaft bearing that is held on the outer shaft, with one of two second part cams comprising an axial attachment that forms at least one part of the bearing inner ring.

Abstract: An adjustable camshaft may include an outer shaft that is hollow and an inner shaft received in the outer shaft and rotatable in the outer shaft. The inner shaft may include a cavity into which oil can be applied. At least a first radial opening may be configured in the outer shaft and at least a second radial opening may be configured in the inner shaft. Thus oil can flow between the cavity and an outside of the outer shaft during overlap of the first radial opening and the second radial opening. The first radial opening on an inside of the outer shaft may have a greater cross-section than on the outside of the outer shaft.

Abstract: An adjustable camshaft can be used in valve drives of internal combustion engines, amongst other places. The adjustable camshaft may include an outer shaft and an inner shaft that is concentric with and rotatably supported in the outer shaft. A cam having a cam bore may be rotatably supported on an outer surface of the outer shaft so as to form a slide bearing gap between the cam and the outer shaft. The cam may be rotatably-fixed to the inner shaft so that the inner shaft and the cam rotate with one another. Furthermore, the adjustable camshaft may include an oil channeling groove disposed beneath the cam in the outer surface of the outer shaft. In many cases, at least one side of the oil channeling groove may be exposed such that it extends beyond the slide bearing gap and the cam.

Abstract: An adjustable camshaft for a valve train of an internal combustion engine may include an inner shaft that is rotatable in an outer shaft, a phase shifter by which the outer shaft and/or the inner shaft are/is adjustable in a phase position formed around an axis of rotation, and a bearing portion for bearing the camshaft, via which the phase shifter can be supplied with a pressurizing medium. The inner shaft may comprise an end on which a screw flange is arranged, and a rotor of the phase shifter may be connected to the screw flange. A free end of the inner shaft comprises a duct that coincides with the axis of rotation for at least partially supplying the phase shifter with a pressurizing medium. The duct may extend at least into the bearing portion.

Abstract: The invention relates to a camshaft comprising a support shaft formed as a hollow shaft. An inner shaft is arranged concentrically in the interior of the support shaft, wherein the inner shaft is rotatable relative to the support shaft. There is arranged on the support shaft a first cam segment with a first recess for receiving the support shaft, which cam segment is rotatable with respect to the support shaft and is connected in a rotationally conjoint manner to the inner shaft via a first opening in the support shaft. The first cam segment has at least two cam contours. The connection between the inner shaft and the first cam segment is furthermore configured such that the first cam segment is axially displaceable relative to the inner shaft and to the support shaft.

Abstract: An adjustable camshaft for a valve drive of an internal combustion engine may include an inner shaft extending through an outer shaft with a cam element disposed on the outer shaft. The cam element may be connected rotationally conjointly to the inner shaft. The cam element may have a shaft passage with an internal bearing surface, which, together with a bearing surface on an outer side of the outer shaft, forms a plain bearing arrangement for the rotatable arrangement of the cam element on the outer shaft. The bearing surface on the outer side of the outer shaft and/or the internal bearing surface of the shaft passage of the cam element may include one or more sections with a spherical shape.

Abstract: A method concerns producing a cam profile of a cam pack with at least two cam elements that can be adjusted relative to each other. The camshaft may comprise an outer shaft, a rotatable inner shaft, a fixed cam element connected to the outer shaft, and an adjustment cam element connected to the inner shaft. The method may comprise processing an adjustment cam contour by a continuous diameter reduction of a segment of the adjustment cam base circle, wherein the adjustment cam base circle is reduced to a diameter that is smaller than a fixed cam nominal circle diameter minus a doubled adjustment cam base circle tolerance. The method may comprise processing a fixed cam contour by reducing a fixed cam contour protrusion in a region between a transition point and a processing point. Upon reaching the transition point a tapping element for converting a revolving motion of the cam elements into a linear motion of the valves is transferred from the fixed cam element to the adjustment cam element.

Abstract: A valve train for actuating gas exchange valves of an internal combustion engine may include a first camshaft that is received such that it can be rotated in a first shaft axis, and a second camshaft that is received such that it can be rotated in a second shaft axis. At least one of the camshafts may be configured as an adjustable camshaft that comprises an outer shaft in which an inner shaft is received such that it can be rotated. At least one of the camshafts may be drive-connected via a drive means to a crankshaft of the internal combustion engine. A phase shifting member may be provided by way of which the phase position of at least one inner shaft can be changed relative to the phase position of at least one outer shaft of the camshaft. The phase shifting member may comprise an arrangement that is spaced apart from both shaft axes.

Abstract: An adjustable camshaft may include an outer shaft that is hollow and an inner shaft received in the outer shaft and rotatable in the outer shaft. The inner shaft may include a cavity into which oil can be applied. At least a first radial opening may be configured in the outer shaft and at least a second radial opening may be configured in the inner shaft. Thus oil can flow between the cavity and an outside of the outer shaft during overlap of the first radial opening and the second radial opening. The first radial opening on an inside of the outer shaft may have a greater cross-section than on the outside of the outer shaft.

Abstract: A camshaft for a valve drive of an internal combustion engine having a variable valve opening time may include an outer shaft and an inner shaft that extends through the outer shaft, with the inner shaft being held rotatably with respect to the outer shaft. The camshaft may further include a cam having a multiple-piece configuration, comprising a first part cam and a second part cam. Either the first part cam or the second part cam may be connected fixedly to the outer shaft so as to rotate with it, and the other part cam may be connected fixedly to the inner shaft so as to rotate with it. The camshaft may also include a bearing inner ring of a shaft bearing that is held on the outer shaft, with one of two second part cams comprising an axial attachment that forms at least one part of the bearing inner ring.

Abstract: The present invention relates to an adjustable camshaft for the valve gear of an internal combustion engine having an outer shaft, on which at least one first cam is arranged which is connected fixedly to said outer shaft so as to rotate with it, and having an inner shaft which extends through the outer shaft and to which at least one second cam is connected fixedly so as to rotate with it and is mounted rotatably on the outer shaft, and it being possible for oil to be conducted from a gap between the outer shaft and the inner shaft through an oil duct in the outer shaft into the region between the second cam and the outer shaft. According to the invention, the second cam is sealed at least partially against the outer shaft by means of at least one sealing element.

Abstract: An adjustable camshaft for a valve drive of an internal combustion engine may include an inner shaft extending through an outer shaft with a cam element disposed on the outer shaft. The cam element may be connected rotationally conjointly to the inner shaft. The cam element may have a shaft passage with an internal bearing surface, which, together with a bearing surface on an outer side of the outer shaft, forms a plain bearing arrangement for the rotatable arrangement of the cam element on the outer shaft. The bearing surface on the outer side of the outer shaft and/or the internal bearing surface of the shaft passage of the cam element may include one or more sections with a spherical shape.

Abstract: An adjustable camshaft can be used in valve drives of internal combustion engines, amongst other places. The adjustable camshaft may include an outer shaft and an inner shaft that is concentric with and rotatably supported in the outer shaft. A cam having a cam bore may be rotatably supported on an outer surface of the outer shaft so as to form a slide bearing gap between the cam and the outer shaft. The cam may be rotatably-fixed to the inner shaft so that the inner shaft and the cam rotate with one another. Furthermore, the adjustable camshaft may include an oil channeling groove disposed beneath the cam in the outer surface of the outer shaft. In many cases, at least one side of the oil channeling groove may be exposed such that it extends beyond the slide bearing gap and the cam.

Abstract: The invention relates to a camshaft comprising a support shaft formed as a hollow shaft. An inner shaft is arranged concentrically in the interior of the support shaft, wherein the inner shaft is rotatable relative to the support shaft. There is arranged on the support shaft a first cam segment with a first recess for receiving the support shaft, which cam segment is rotatable with respect to the support shaft and is connected in a rotationally conjoint manner to the inner shaft via a first opening in the support shaft. The first cam segment has at least two cam contours. The connection between the inner shaft and the first cam segment is furthermore configured such that the first cam segment is axially displaceable relative to the inner shaft and to the support shaft.

Abstract: The invention relates to an adjustable camshaft for the valve gear of an internal combustion engine, comprising an outer shaft, on which at least one first cam is arranged and connected to the outer shaft in a rotationally fixed manner, and an inner shaft extending through the outer shaft, to which inner shaft at least one second cam is connected in a rotationally fixed manner, wherein the second cam connected to the inner shaft in a rotationally fixed manner has a cam hole and is rotatably supported on a seating point on the outer shaft. According to the invention, at least one oil groove is introduced at the seating point in the outer shaft and/or in the inner wall of the cam hole, into which oil groove oil is guided from a gap between the outer shaft and the inner shaft through at least one passage extending through the outer shaft.

Abstract: The invention relates to a camshaft, in particular for motor vehicle engines, comprising an outer shaft (1), an inner shaft (2) arranged coaxially in the outer shaft (1), first functional elements (3) rigidly arranged on the outer shaft (1), second functional elements (4a, 4b), which are rotatably arranged on the outer shaft (1) and fastened to the inner shaft (2) in a rotationally fixed manner, and a phase adjuster (5) connected to the outer shaft (1) and the inner shaft (2) for rotating the inner shaft (2) relative to the outer shaft (1), wherein the phase adjuster (5) is fastened to the inner shaft (2) and thereby a torque is applied. According to the invention, one of the functional elements (4a, 4b) connected to the inner shaft (2) in a rotationally fixed manner has tool accommodation surfaces (11) on the cylindrical surface side outside of a functional surface (12a, 12b). The invention further relates to such a functional element.

Abstract: The present invention relates to an adjustable camshaft for the valve gear of an internal combustion engine having an outer shaft, on which at least one first cam is arranged which is connected fixedly to said outer shaft so as to rotate with it, and having an inner shaft which extends through the outer shaft and to which at least one second cam is connected fixedly so as to rotate with it and is mounted rotatably on the outer shaft, and it being possible for oil to be conducted from a gap between the outer shaft and the inner shaft through an oil duct in the outer shaft into the region between the second cam and the outer shaft. According to the invention, the second cam is sealed at least partially against the outer shaft by means of at least one sealing element.