A power head for a powered concrete roller screed includes a handle and a driver housing at a distal end of the handle. A cordless, battery-operated driver is received in the driver housing. A head actuator includes a translatable link extending along the handle and an eccentric cam. The eccentric cam is operatively connected to the translatable link within the drive housing such that translation of the translation link imparts rotation of the eccentric cam about a rotational axis of the eccentric cam to an actuated position. The eccentric cam is adjacent a trigger of a cordless, battery-operated driver and is configured to depress the trigger when the eccentric cam is rotated about its rotational axis to the actuated position.

In a compressor for discharging a medium, in particular tire sealant that is to be discharged from a container into a tire, wherein a motor (1) of the compressor (P) drives a step-up transmission wheel (3, 3.1) for moving at least one piston (6-6.6) in a compression chamber (7), the step-up transmission wheel (3, 3.1) is intended to be provided only partially on its circumference with a toothing (20) and/or to consist of two toothed wheels (11, 12) lying on each other.

This inventive mechanism relies on to connect a sliding carrier under sliding motion with a rotating crankshaft through a connecting disk or member in order to efficiently convert a reciprocating motion to a rotary motion or vice versa. The connecting disk is generally a uniformly circular disk, pivotally coupled within the sliding carrier and a crankpin of traditional crankshaft is eccentrically coupled with this connecting disk further. Such mechanical setup effectuates the siding carrier along with the connecting disk to slide along the reciprocating motion, rotationally rearrange the connecting disk within the siding carrier in presence of a gripping reaction by the crank pin and enforces the crankshaft to rotate by motion conversion which effectively eliminates a portion of loses in fuel efficiency incurred by the traditional mechanism.

Subject of the present invention, is an internal combustion engine comprising one or more cylinders, inside each of which a piston slides in variable strokes, which realizes the strokes of intake, compression, combustion and exhaust with a 360° rotation of two crank shafts.

The present invention is in the field of engine destined to automotive applications as well as the engine destined to fixed installation such as generators.

Subject of the present invention, is an internal combustion engine comprising one or more cylinders, inside each of which a piston slides in variable strokes, which realizes the strokes of intake, compression, combustion and exhaust with a 360° rotation of two crank shafts.

The present invention is in the field of engine destined to automotive applications as well as the engine destined to fixed installation such as generators.

A power-driven reciprocating tool may include a transmission mechanism that converts rotational force from a motor to linear force to be output by a reciprocating mechanism coupled thereto, and a counterbalancing mechanism coupled to the transmission mechanism to counter-balance forces generated by the reciprocating mechanism. The transmission mechanism may include a planetary gear assembly including a sun gear in meshed engagement with at least one planet gear. In response to a force converted by and transmitted from the transmission mechanism, the reciprocating mechanism may move in a first linear direction, and the counterbalancing mechanism may move in a second linear direction, opposite the first linear direction. The opposite linear movement of the reciprocating mechanism and the counterbalancing mechanism may counteract forces generated by the reciprocating motion of the reciprocating mechanism, thus reducing vibration output by the tool.

A power-driven reciprocating tool may include a transmission mechanism that converts rotational force from a motor to linear force to be output by a reciprocating mechanism coupled thereto, and a counterbalancing mechanism coupled to the transmission mechanism to counter-balance forces generated by the reciprocating mechanism. The transmission mechanism may include a planetary gear assembly including a sun gear in meshed engagement with at least one planet gear. In response to a force converted by and transmitted from the transmission mechanism, the reciprocating mechanism may move in a first linear direction, and the counterbalancing mechanism may move in a second linear direction, opposite the first linear direction. The opposite linear movement of the reciprocating mechanism and the counterbalancing mechanism may counteract forces generated by the reciprocating motion of the reciprocating mechanism, thus reducing vibration output by the tool.

A cryogenic refrigerator includes a displacer that is reciprocably mounted within a cylinder; a spool valve that is connected to the compressor and performs switching between an intake mode where a high-pressure refrigerant gas is supplied from the compressor to the cylinder and an exhaust mode where a low-pressure refrigerant gas within the cylinder is made to flow back to the compressor; and a drive unit that drives the spool valve. The spool valve has a valve body, and a drive rod that moves relative to the valve body and is integrated with the spool. The drive unit performs driving so that the magnitude of a speed when the drive rod moves from a top dead center to a bottom dead center is different from the magnitude of a speed when the drive rod moves from the bottom dead center to the top dead center, at the same displacement position.

An internal combustion engine includes a standard connecting rod as well as a gear rack. The connecting rod can be a standard connecting rod that reciprocates with the piston and that drives a rotatable crank mechanism to convert the reciprocating motion of the piston into rotation of the crankshaft. The gear rack is also connected to and reciprocates with the piston. The gear rack is engaged with a gear that is mounted on the crankshaft. A one-way drive mechanism is provided between the gear and the crankshaft that transmits torque (i.e. rotary force) to the crankshaft only during the power stroke of the piston.

An internal combustion engine includes a standard connecting rod as well as a gear rack. The connecting rod can be a standard connecting rod that reciprocates with the piston and that drives a rotatable crank mechanism to convert the reciprocating motion of the piston into rotation of the crankshaft. The gear rack is also connected to and reciprocates with the piston. The gear rack is engaged with a gear that is mounted on the crankshaft. A one-way drive mechanism is provided between the gear and the crankshaft that transmits torque (i.e. rotary force) to the crankshaft only during the power stroke of the piston.