Device for the relative rotation of two shafts geared together,in particular a crankshaft and a camshaft borne in a machine sump

Claim 1

A device for the relative variation of position in rotation of a driven shaft, especially of a cam shaft displaceable in relation to the crank-shaft of an internal combustion engine, comprising a shifting arrangement provided on the shaft and an actuating arrangement (17) arranged remotely from the shaft on the engine housing (lid 18), where the shifting arrangement comprises an axially-displaceable coupling member (14) connecting the shaft (cam shaft 1) with a separately- arranged drive wheel (6) movable in angle of rotation in relation to the shaft, and the coupling member (14) is in connection with the actuating arrangement (17) through a coupling rod (19) arranged for guidance on the engine with interposition of a swivel joint (20) comprising three degrees of freedom, and further the coupling rod (19) is in disengageable connection with the actuating arrangement (17), characterised in that the shaft (1) comprises, in an engine guided end region (plain bearing 3), a concentric aperture (11) which servesforthe supporting, with movable angle of rotation, of a hub (9) of the drive wheel (6), which is centred and arranged in axially-secured manner, with movable angle of rotation, on a shaft collar (7) arranged on the free shaft end, while the hub (9) extending substantially in the aperture (11) is provided on the internal circumference with a skew or helical toothing (13) for engagement of the coupling member (14) on the drive wheel side, which member is in engagement oi- the shaft side with a spur toothing (15') arranged in a further region of the aperture (11).

Claim 2

A device for the relative variation of position in rotation of a driven shaft, especially of a cam shaft displaceable in relation to the crank-shaft of an internal combustion engine, comprising a shifting arrangement provided on the shaft and an actuating arrangement (17) arranged remotely from the shaft on the engine housing (lid 18), where the shifting arrangement comprises an axially-displaceable coupling member (14) connecting the shaft (cam shaft 1) with a separately- arranged drive wheel (6) movable in angle of rotation in relation to the shaft, and the coupling member (14) is in connection with the actuating arrangement (17) through a coupling rod (19) arranged for guidance on the engine with interposition of a swivel joint (20) comprising three degrees of freedom, and further the coupling rod (19) is in disengageable connection with the actuating arrangement (17), characterised in that the shaft (1) comprises, in an engine guided end region (plain bearing 3), a concentric aperture (11) which servesforthe supporting, with movable angle of rotation, of a hub (9) of the drive wheel (6), which is centred and arranged in axially-secured manner, with movable angle of rotation, on a shaft collar (7) arranged on the free shaft end, while the hub (9) extending substantially in the aperture (11) is provided on the internal circumference with a skew or helical toothing (13) for engagement of the coupling member (14) on the drive wheel side, which member is in engagement oi- the shaft side with a spur toothing (15') arranged in a further region of the aperture (11).

Claim 5

A device according to Claims 1-3, characterised in that the swivel joint (20) comprises axially-spaced, radially-directed sliding or rolling devices (needle bearings 21) in an end aperture of the coupling member (14), between which there is arranged a disc flange (22) connected with the coupling rod (19).

Claim 6

A device according to Claims 1-4, in which the actuating arrangement (17) actuates the coupling rod (19) through a piston (23) displaceable by medium pressure and the connection of coupling rod (19) and piston (23) can be produced through the free end of the actuating arrangement (17), and the actuating arrangement (17) is a hydraulically double-acting cylinder/piston unit, characterised in that a cylinder (24) is of open configuration at its end (25) remote from the shifting arrangement for the arrangement of the piston (23), which in its initial position (44) effected by the skew or helical toothing (13) strikes with parts of its free end face (42) on a separate closure lid (34) covering the cylinder (24), which lid can be secured to the engine housing lid (18).

Claim 8

A device according to Claims 5 and 6, characterised in that the piston (23) is guided in the cylinder (24) by means of an elastic sealing ring (35), in that the piston further comprises on its end (36) facing the shifting arrangement a sealing shank (37) of relatively large diameter, which is guided by means of elastic sealing rings (39) arranged in axially-spaced circumferential grooves of a radially inwardly-directed collar (38) on the cylinder (24) in the region of the forward external circumferential section (27).

Claim 9

A device according to Claims 5-7, characterised in that the annular passages (29, 30) in connection with control chambers (40, 41) on both sides of the piston (23) in the cylinder (24) are each connected with a conduit (45, 46) formed separately in the engine housing lid (18), and both conduits are in communication with a hydraulic system (43), separate from the internal combustion engine, with a reservoir (47) storing hydraulic medium under pressure, while the conduits to the control chamber (40, 41) are controllable by means of a valve arrangement (51).

Claim 11

A device according to Claims 1-9, characterised in that the shaft (1) comprises a plain bearing (3) adjacent to the shaft collar (7), from which a radial lubricating oil bore (54) leads to the bearing bore (12) accommodating the hub (9) of the drive wheel (6) in the aperture (11), in that a further plain bearing (4) is arranged between adjacent cams (2) of the shaft.