Vane-type camshaft adjuster system

Abstract

The object of the invention is to provide an economical vane-type camshaft adjuster system that meets the various requirements of various motors. For this purpose, according to the invention a modular system is provided for the valves of a vane-type camshaft adjuster system. Two different embodiments of valves are proposed. With one embodiment, a valve with mid-locking and without mid-locking may be constructed using the same bush. With the other embodiment, a valve with and without special utilization of the camshaft alternating torques may be constructed using the same bush.

1 . 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,   a locking pin associated with said pressure chamber, which locking pin is aligned parallel to a central axis and which in a locking position fixes the rotor relative to the stator in an intermediate position lying between “early” and “late” end positions,   an electrohydraulic 4/4-way valve for controlling the two hydraulic chambers, the 4/4-way valve comprising:
 a supply port (P), 
 a first working port (A) for the first hydraulic chamber, 
 a second working port (B) for the second hydraulic chamber, and 
 a tank port (T), 
   by means of the 4/4-way valve in a first position ( 1 ) during disconnection, stopping or starting of the drive motor through simultaneous hydraulic interconnection of the two working ports (A, B), the two hydraulic chambers being relieved to an unpressurized state relative to the tank port (T) so that the locking pin moves into the locking position, the 4/4-way valve being of a cartridge style of construction and comprising a bush, which is provided with three openings disposed axially adjacent to one another and inside which a hollow piston is axially displaceable along a running surface, and a cup base which is provided at the magnet-side piston end, which cup base is supported under spring loading against a displaceable tappet of a magnet part, the piston comprising:   two circumferential annular control grooves,   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 second 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).   
     
     
         2 . Vane-type camshaft adjuster system according to  claim 1 , wherein an inner running surface of the bush is drilled in one diameter in a region of the openings associated with the two working ports (A, B). 
     
     
         3 . Vane-type camshaft adjuster system according to  claim 2 , wherein an inside diameter of the bush in an axial region between the magnet part and the outer web positioned closest thereto is designed with an inside diameter that is widened relative to the running surface. 
     
     
         4 . Vane-type camshaft adjuster system according to  claim 1 , wherein the recess associated with the supply port (P) is provided axially between the openings associated with the working ports (A, B). 
     
     
         5 . 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). 
   
     
     
         6 . Vane-type camshaft adjuster system according to  claim 5 , wherein an inner running surface of the bush is drilled in one diameter in a region of the openings associated with the two working ports (A, B). 
     
     
         7 . Vane-type camshaft adjuster system according to  claim 6 , wherein an inside diameter of the bush in an axial region between the magnet part and the outer web positioned closest thereto is designed with an inside diameter that is widened relative to the running surface. 
     
     
         8 . Vane-type camshaft adjuster system according to  claim 5 , wherein the recess associated with the supply port (P) is provided axially between the openings associated with the working ports (A, B). 
     
     
         9 . 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). 
   
     
     
         10 . A set of valves according to  claim 9 , further comprising:
 at least one rotor having at least one vane that divides a pressure chamber formed circumferentially between two radially inwardly directed webs of a stator into the two hydraulic chambers working in opposite directions.   
     
     
         11 . A set of valves according to  claim 9 , wherein the valve with the mid-locking piston further comprises:
 a locking pin associated with said pressure chamber, which locking pin is aligned parallel to a central axis and which in a locking position fixes the rotor relative to the stator in an intermediate position lying between “early” and “late” end positions; and   wherein by means of the valve in a first position ( 1 ) during disconnection, stopping or starting of the drive motor through simultaneous hydraulic interconnection of the two working ports (A, B), the two hydraulic chambers being relieved to an unpressurized state relative to the tank port (T) so that the locking pin moves into the locking position.   
     
     
         12 . A set of valves according to  claim 9 , wherein:
 each bush is provided with at least three openings disposed axially adjacent to one another and inside which the piston is axially displaceable along a running surface, and   a cup base is provided at the magnet-side piston end, which cup base is supported under spring loading.   
     
     
         13 . A set of valves according to  claim 12 , wherein, in the valve with the piston without mid-locking, camshaft alternating torques raise the hydraulic pressure in the first hydraulic chamber above the hydraulic pressure inside the bush.