Vane-type camshaft adjuster system

Vane-type camshaft adjuster system for a drive motor, comprising:

• a rotor having at least one vane that divides a pressure chamber formed circumferentially between two radially inwardly directed webs of a stator into two hydraulic chambers working in opposite directions,
• an electrohydraulic 4/4-way valve for controlling the two hydraulic chambers, the 4/4-way valve comprising:
• a first working port (A) for the first hydraulic chamber,
• a second working port (B) for the second hydraulic chamber,
• a supply port (P) disposed in relation to a central axis between said two working ports (A, B), and
• a tank port (T),
• the 4/4-way valve being of a cartridge style of construction and comprising a bush, which is provided with at least four openings disposed axially adjacent to one another, of which a first and a second opening are associated with the one of the two working ports (B and/or A), of which the first opening positioned closer to the supply port (P) is provided with a non-return valve, by means of which hydraulic fluid is directed from the first hydraulic chamber associated with said one working port (B and/or A) through the other working port (A and/or B) to the second hydraulic chamber associated with said other working port (A and/or B) when:
• the second opening is closed by a hollow piston, and
• camshaft alternating torques raise the hydraulic pressure in the first hydraulic chamber above the hydraulic pressure inside the bush,
• inside said bush the piston being axially displaceable along a running surface and at the magnet-side piston end a cup base is provided, which is supported under spring loading against a displaceable tappet of a magnet part,
• wherein the piston comprises:
• at least one circumferential annular control groove,
• an outflow recess at the magnet-side piston end leading to the tank port (T) and aligned transversely of the central axis, and
• a circumferential outer web adjacent to said outflow recess, past which a hydraulic flow may be conveyed from the spring-side working port (B) to the outflow recess, said circumferential outer web at the spring-side piston end takes the form of a circumferential control edge for directing hydraulic fluid to the tank port (T).

Set of valves for a vane-type camshaft adjuster system for a drive motor, comprising:

• at least two types of valves, each valve comprising:
• a first working port (A) for a first hydraulic chamber,
• a second working port (B) for a second hydraulic chamber,
• a supply port (P), and
• a tank port (T),
• an identical magnet part,
• an identical bush, and
• one of a piston with mid-locking and a piston without mid-locking,
• wherein:
• the piston with mid-locking comprises:
• two circumferential annular control grooves,
• an outflow recess at a magnet-side piston end leading to the tank port (T) and aligned transversely of a central axis, and
• a circumferential outer web adjacent to said outflow recess, past which a hydraulic flow may be conveyed from the second working port (B) to the outflow recess, said circumferential outer web at a spring-side piston end takes the form of a circumferential control edge for directing hydraulic fluid to the tank port (T);
• and
• the piston without mid-locking comprises:
• at least one circumferential annular control groove,
• an outflow recess at a magnet-side piston end leading to the tank port (T) and aligned transversely of the central axis, and
• a circumferential outer web adjacent to said outflow recess, past which a hydraulic flow may be conveyed from a spring-side working port (B) to the outflow recess, said circumferential outer web at the spring-side piston end takes the form of a circumferential control edge for directing hydraulic fluid to the tank port (T).