Abstract: A hydraulic unit (5) is provided for a cylinder head (2) of an internal combustion engine with a hydraulically variable valve train (1). In the hydraulic unit, a high-pressure chamber (11), a medium-pressure chamber (12), and a low-pressure chamber (16) used as the hydraulic medium reservoir are formed. The low-pressure chamber communicates via a throttle point (17, 17?, 17?, 17??) with the medium-pressure chamber, and the throttle point is formed by a displaceable valve body (19, 19?, 19?, 19??) and has through-flow cross sections of different sizes according to a position of the valve body.

Abstract: A coupling device (1) of a switchable cam follower (2), in which a borehole (9) extends above a contact (8) for a support element in an outer lever (3) of the cam follower (2), and this borehole has a first section (10) of large diameter that starts from an outer side (11) of a crosspiece (6) on the other end (7) to which connects to a second section (12) of accordingly smaller diameter up to directly before an inner side (13) of the crosspiece (6). A smooth cylindrical coupling slide (14) is guided in a sealing manner through the second section (12), and this coupling slide projects with a sub-region (15) into the first section (10). This sub-region (15) is encompassed by a compression spring (16) that acts, on one end, against an annular end (17) formed between the sections (10, 12) and, on the other end, against a catch element (19) arranged on the lateral surface (18) of the sub-region (15).

Abstract: A hydraulic unit (5) is provided for a cylinder head (2) of an internal combustion engine with a hydraulically variable valve train (1). In the hydraulic unit, a high-pressure chamber (11), a medium-pressure chamber (12), and a low-pressure chamber (16) used as the hydraulic medium reservoir are formed. The low-pressure chamber communicates via a throttle point (17, 17?, 17?, 17??) with the medium-pressure chamber, and the throttle point is formed by a displaceable valve body (19, 19?, 19?, 19??) and has through-flow cross sections of different sizes according to a position of the valve body.

Abstract: A coupling device (1) of a switchable cam follower (2), in which a borehole (9) extends above a contact (8) for a support element in an outer lever (3) of the cam follower (2), and this borehole has a first section (10) of large diameter that starts from an outer side (11) of a crosspiece (6) on the other end (7) to which connects to a second section (12) of accordingly smaller diameter up to directly before an inner side (13) of the crosspiece (6). A smooth cylindrical coupling slide (14) is guided in a sealing manner through the second section (12), and this coupling slide projects with a sub-region (15) into the first section (10). This sub-region (15) is encompassed by a compression spring (16) that acts, on one end, against an annular end (17) formed between the sections (10, 12) and, on the other end, against a catch element (19) arranged on the lateral surface (18) of the sub-region (15).