An adjustable stroke device for a random orbital machine has a housing with a central axis and a wall defining a cavity. At least one counterweight is movably disposed at least partially within the cavity. A mounting assembly is disposed at least partially within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjuster couples the at least one counterweight with the mounting assembly. The stroke adjuster enables the at least one counterweight and mounting assembly to move with respect to one another such that a distance between the at least one counterweight and the mounting assembly may be variably adjusted which, in turn, variably adjust a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing. The stroke adjuster has an adjuster ring and a cam mechanism secured with the adjuster ring.

An adjustable stroke device for a random orbital machine has a housing with a central axis and a wall defining a cavity. At least one counterweight is movably disposed at least partially within the cavity. A mounting assembly is disposed at least partially within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjuster couples the at least one counterweight with the mounting assembly. The stroke adjuster enables the at least one counterweight and mounting assembly to move with respect to one another such that a distance between the at least one counterweight and the mounting assembly may be variably adjusted which, in turn, variably adjust a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing. The stroke adjuster has an adjuster ring and a cam mechanism secured with the adjuster ring.

A force transmission device for a variable valve drive of an internal combustion engine. The force transmission device has a first lever device. The first lever device has a first cam follower and a first receptacle for the first cam follower. The first cam follower is displaceable and lockable in the first receptacle. The force transmission device has a second lever device. The second lever device has a second cam follower and a second receptacle for the second cam follower. The second cam follower is displaceable and lockable in the second receptacle.

A force transmission device for a variable valve drive of an internal combustion engine. The force transmission device has a first lever device. The first lever device has a first cam follower and a first receptacle for the first cam follower. The first cam follower is displaceable and lockable in the first receptacle. The force transmission device has a second lever device. The second lever device has a second cam follower and a second receptacle for the second cam follower. The second cam follower is displaceable and lockable in the second receptacle.

A positioning device, comprising a base element, a carrier element to be positioned relative to the base element along a z-axis as well as at least one first, second, third and fourth slide element, wherein the first, second, third or fourth slide element on the one hand is disposed displaceably by means of a first, second, third or fourth base guide device along a first, second, third or fourth base line on the base element and on the other hand by means of a first, second, third or fourth ascent guide device along a first, second, third or fourth ascent line on the carrier element, wherein the first, second, third or fourth ascent line and the first, second, third or fourth base line run in a projection along the z-axis parallel to one another and with respectively constant different angles of inclination relative to the z-axis. It is provided that the first, second, third and fourth ascent guide device are arranged with respect to one another in such a manner that respectively in at least one projection perpendicular to the z-axis, the first and the second ascent line or the third and fourth ascent line, respectively, are inclined opposite to one another relative to the z-axis so that a synchronous displacement of the first, second, third and fourth slide element relative to the base element brings about a displacement of the carrier element relative to the base element exclusively along the z-axis.

A force transmission device for a variable valve drive of an internal combustion engine. The force transmission device has a first lever device. The first lever device has a first cam follower and a first receptacle for the first cam follower. The first cam follower is displaceable and lockable in the first receptacle. The force transmission device has a second lever device. The second lever device has a second cam follower and a second receptacle for the second cam follower. The second cam follower is displaceable and lockable in the second receptacle.

A force transmission device for a variable valve drive of an internal combustion engine. The force transmission device has a first lever device. The first lever device has a first cam follower and a first receptacle for the first cam follower. The first cam follower is displaceable and lockable in the first receptacle. The force transmission device has a second lever device. The second lever device has a second cam follower and a second receptacle for the second cam follower. The second cam follower is displaceable and lockable in the second receptacle.

A system for variable actuation of an engine valve of an engine includes a master piston driven by a cam of a camshaft. A slave piston is driven by the master piston by a volume of pressurized fluid. The slave piston causes the engine valve to open, against the action of a spring. A control valve controls a communication between pressurized fluid and an environment at lower pressure, with which a fluid accumulator is in communication. A control unit is programmed for controlling the control valve according to one or more different valve modes. When one of these valve modes is actuated, the control valve opens the communication in advance with respect to the end of the lift cycle of the cam, and not after closing of the engine valve to prevent or reduce a decrease in pressure in the volume of pressurized fluid after closing of the engine valve.

A system for variable actuation of an engine valve of an engine includes a master piston driven by a cam of a camshaft. A slave piston is driven by the master piston by a volume of pressurized fluid. The slave piston causes the engine valve to open, against the action of a spring. A control valve controls a communication between pressurized fluid and an environment at lower pressure, with which a fluid accumulator is in communication. A control unit is programmed for controlling the control valve according to one or more different valve modes. When one of these valve modes is actuated, the control valve opens the communication in advance with respect to the end of the lift cycle of the cam, and not after closing of the engine valve to prevent or reduce a decrease in pressure in the volume of pressurized fluid after closing of the engine valve.

An adjustable stroke device for a random orbital machine has a housing with a central axis and a wall defining a cavity. At least one counterweight is movably disposed at least partially within the cavity. A mounting assembly is disposed at least partially within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjuster couples the at least one counterweight with the mounting assembly. The stroke adjuster enables the at least one counterweight and mounting assembly to move with respect to one another such that a distance between the at least one counterweight and the mounting assembly may be variably adjusted which, in turn, variably adjust a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing. The stroke adjuster has an adjuster ring and a cam mechanism secured with the adjuster ring.