Abstract:
A tappet (1) is to be engageable on to at least three different cam profiles with an optional zero lift. To this end the tappet (1) consists of an annular base section (2) enclosing a circular base section (3). Both base sections (2, 3) can be coupled together via radially adjustable coupling devices (10). An additional, axially movable inner piston (18) is fitted in a guide sleeve (7) of the circular base section (3). The inner piston (18) can be decoupled via further coupling means (23) so that the tappet (1) can be completely decoupled from the guide sleeve (7).
Abstract:
The invention relates to a driven lever for actuating a gas valve in an internal combustion engine having means for compensating the valve clearance. In the prior art, a driven lever is dome-shaped in the region of the support and fitted with a clearance compensation device. This arrangement is not suitable for actuating two valves at the same time. It is the aim of the invention to ensure the clearance-free actuation of the gas valves in a multi-valve internal combustion engine as compactly as possible. According to the invention, to this end a driven lever (1) for actuating two gas valves (6, 7) simultaneously, is forked.
Abstract:
The invention concerns a hydraulic valve-tappet for internal-combustion engines, the tappet having a cup-shaped housing (1) with a cylindrical wall (2). The aim of the invention is to reduce the weight of the tappet in the simplest way. This aim is achieved by virtue of the fact that the wall (2) of the tappet housing is pierced by window-like apertures (12).
Abstract:
The outside of the housing (2) of a support (1) for a valve gear pull-rod of an internal combustion engine has serrations (13) which are pressed during assembly into a drilling (4) in a cylinder head (5). During the pressing operation, material is scraped off the serration material and is forced wholly or partly into the spaces between the serrations towards their bases. This ensures that the clearance-eliminating component (1) is prevented from rotating in the drilling (4).
Abstract:
In a hydraulic-action tappet (1) the backlash compensation element (5) is secured axially in the direction away from the cam via an axial projection (11) of a guide unit (10) which extends radially inwards from the housing (2). The axial projection (11) at the end away from the cam has a wider diameter (14) to which a disk spring plate (16) for fixing a pressure piston (7) of the backlash compensation element (5) is applied with a holding force which is directed radially outwards.
Abstract:
A tappet (2) has a hydraulic clearance compensating element (8) composed of a high pressure chamber (18), a housing (3) with a spring-loaded, longitudinally movable compensating piston (15) and a free piston (11) with a smaller diameter than the compensating piston (15). In order to obtain by simple manufacturing means a reduced elasticity in valve operation during the base circle phase of a cam (6), the ratio between the projected surface (20) of the compensating piston (1) that faces the high pressure chamber (18) and the projected surface (19) of the free piston (11) that faces the high pressure chamber (18) is higher than 3.
Abstract:
An hydraulic play compensating element (1) is disclosed, for example for a valve gear mechanism of an internal combustion engine. Its play compensating function is ensured by a defined leak gap (14). The components (3, 5) contiguous to the leak gap (14) are designed in such a way that the leak gap (14) has an optimum size over the whole range of operation temperatures of the element (1).
Abstract:
A valve gear mechanism (1) for gas exchange valves (2)is capable of being switched between different valve lifts. For each gas exchange valve (2) the valve gear mechanism (1) has two separate cam followers (4, 5) with a common swivelling axis, thus forming a valve lifter. The cam follower (4) can be actuated by a cam (8) whereas the cam follower (5) faces a gas exchange valve (2). The two cam followers (4, 5) can swing towards each other and be mutually coupled by coupling means (15) to achieve a large valve lift. The cam followers are preferably coupled in the base circle of the cam. Stoppers (14) are provided between the two cam followers (4, 5) to define the relative position of recesses (17, 16) that receive the coupling means. These stoppers (14) can remarkably displace the coupling means (15) with little wear and hardly any actuation effort, even when the internal combustion engine turns at high speeds of rotation.
Abstract:
A switchable supporting component (30) is to be designed in such a way that a pull-rod engaging at one end (35) of it can be fully operatively separated from the control cam. The invention effects this in that in the housing (31) there runs at least one further radial drilling (37) aligned in a large cam movement phase in which there is a coupling component (49) movable along the drilling which, when the cam is disconnected from the pull-rod, can move in such a way that it laps over an annular gap (41) formed between the housing (31) and the cylinder head (10) and runs at the same time in the two drillings (37) in the housing (31) and the cylinder head (10). Thus, the idle stroke of the housing (31) necessary when the pull-rod is disconnected is avoided. Disconnection can take place even at medium to fast rotation speeds, since a pressure spring (47) no longer keeps the pull-rod in permanent contact with the cam via the housing (31) in the disconnection phase.
Abstract:
A tappet rod (1) for a valve gear mechanism in an internal combustion engine is designed as a lightweight construction. Thus, its outer shroud (3) consists of two separate sections (14, 15), with a thin-walled projection (16) extending from the lower section (15) toward the cam and an oil way formed between this projection and the first section (14). The lower section (15) is made as a thin-walled element.