Abstract:
394,777. Valve gear. HALFORD, F. B., 9, Golden Square, London. April 4, 1932, No. 9633. [Class 7 (vi).] In valve gear in which the operating thrust is transmitted through a column or pad of liquid confined in a recess in the rocker arm to which further liquid may be admitted past a non- return valve to take up clearance, the non- return valve is free to open and close under the action of gravity and its own inertia, the use of a spring being dispensed with. The Figure shows a cam-actuated rocker 12 in which the cam engages a plunger 16 sliding in a recess in the rocker, to which oil is delivered through passages 24, 25, 26 and past a non-return valve 21, which during the opening movement of the valve gear becomes seated owing to its inertia, on a shoulder 20. The lift of the valve is restricted to a very small amount by a stop 22. The inward movement of the plunger 16 is limited by a shoulder 27, the height of which may be adjusted by placing shims thereon. The outward movement is restricted by a pin 30 engaging a recess in the plunger, and rotation of the plunger is prevented by a flat 28. Air trapped in the recess escapes through a flat formed along one side of the plunger. The poppet valve 21 may be replaced by a ball valve seating with line contact. In a modification, the ball valve seats upon a cup member secured in the hollow plunger, the oil passing between the cup member and plunger, and through a hole at the bottom of the plunger, on to the cam.
Abstract:
A method for optimizing response time of a latch in a cylinder deactivation rocker arm assembly is provided. The latch is configured to move between an engaged position with an inner arm of the rocker arm assembly and a retracted position. A major outer diameter (L1) of the latch is determined. An installed length (L2) of a spring biasing the latch is determined. A clearance (L3) between L1 and a major inner diameter of an outer arm of the rocker arm assembly is determined. A radial clearance (L4) between a cage coupled to the outer arm and a major inner diameter of the latch is determined. A minor diameter (L5) of the latch is determined. A relationship between the response time of the latch and L1, L2, L3, L4 and L5 is established. Components of the cylinder deactivation rocker arm assembly are selected based on the relationship.
Abstract:
Bei einem hydraulischen Ventilspielausgleichselement für den Steuertrieb eines Verbrennungsmotors, welches als Reverse-Spring/Freeball-Element ausgebildet ist, mit einem zylindrischen Gehäuse, einem darin mit Dichtspiel geführten zylindrischen Kolben (21) und einem Steuerventil (20), welches zwischen einem Niederdruckraum (22) des Kolbens (21) und einem Hochdruckraum (24) des Gehäuses an einem Kolbenboden (25) angeordnet ist und einen Schließkörper (27) aufweist, der bei Ausführung eines Hubes (28) in der Schließrichtung gegen die Wirkung einer Steuerventilfeder (34) an einem eine Axialbohrung (23) des Kolbenbodens (25) umgebenden Ventilsitz (26) und in der Öffnungsrichtung an einer Anschlagfläche (29) einer den Schließkörper (27) umgebenden Ventilkappe (30) anlegbar ist, befindet sich erfindungsgemäß im Bereich der Axialbohrung (23) für den Schließkörper (27) eine enge Führungsfläche (32) mit Unterbrechungen, welche einen Volumenstrom von Hydraulikmittel zwischen dem Hochdruckraum (24) und dem Niederdruckraum (22) ermöglichen.
Abstract:
The invention relates to a control arrangement for an inlet valve in a piston engine adapted between a cam device (5) of a camshaft (4) of the engine (1 ) and an inlet valve mechanism (6) arranged to open and close the inlet valve (3) in association with a cylinder of the engine, which control arrangement (7) comprises a body part (8), in which a piston device (9) is movably arranged to be in force transmission connection with the camshaft (4) and the valve mechanism (6), said body part (8) and the piston device (9) together defining a first chamber (13), into which hydraulic medium can be selectively fed, and a second chamber (19) connected to the first chamber via duct means (18,18', 18"), the flow of hydraulic medium from the first chamber (13) to the second chamber (19) being controlled for providing a delay in the closing of the inlet valve (3). The body p a r t ( 8 ) i s provided with two or more flow ducts (18a,18b,18c;18'a,18'b;18"a,18"b,18"c) for arranging different routes for the flow of hydraulic medium from the first chamber (13) to the second chamber (19). Control means (17, 17', 17") are provided for selecting the route of flow to be utilised in each case to provide different closing delay.
Abstract:
A hydraulic lash adjuster (30) for a valve train (10) of an internal combustion engine uses a partial recirculation feature in order to provide device cooling while also retaining many of the benefits associated with leak recirculation. The hydraulic lash adjuster (30) includes a hollow piston (40) that is received in an axial bore (33) of a body component (31). The annular clearance area (71) between the hollow piston (40) and the body (31) defines a plurality of leak escape paths (72) and a plurality of leak recirculation paths (71). The portion of the leaked oil recirculated is on a same order of magnitude as the remaining portion of the leaked oil that is allowed to escape back to sump.
Abstract:
A control arrangement for, and a method for controlling the closing movement of, a valve operating assembly in a piston engine adapted between a cam device (5) of a camshaft (4) of the engine (1 ) and an inlet valve mechanism (6) arranged to open and close the inlet valve (3) in association with a cylinder of the engine. The control arrangement (7) comprises a body part (8), in which a piston de¬ vice (9) is movably arranged to be in force transmission connection with the camshaft (4) and the valve mechanism (6), the body part (8) and the piston device (9) together defining a first chamber (13), into which hydraulic medium can be selectively fed for providing a delay in the closing of the inlet valve (3). The body part (8) is provided with a first duct (16) for releasing of pressure in the first chamber (13) under control of a gu ide member (10) movably arranged in the body part (8) between the cam device (5) and the piston device (9). The guide member (10) includes a third chamber (18), which is arranged to be in communication with the first duct (16) and a control piston (20) located in said third chamber (18) and movably arranged with regard to the guide member (10) for controlling pressure medium flow through said third chamber (18).