A cover for a rod end of an actuator comprises a mounting collar for surrounding and mounting to a portion of the rod end. The collar is deformable such that it may be mounted over a rod eye mounted to the rod end. The cover further comprises a shield extending from the collar and shaped such that when attached to the rod end the shield shields a portion of rod end to prevent fluid or foreign object ingress to the rod end.

A cylinder stroke determination system and a method of determining a stroke of a cylinder are provided. The system includes a cylinder having a rod and a barrel, a sensing cylinder configured to operate with the cylinder, and a processor. The sensing cylinder includes a sensing cylinder base coupled to the barrel of the cylinder, a sensing cylinder rod coupled to the connecting portion of the rod of the cylinder, a photon emitter coupled to the sensing cylinder base and configured to emit a photon toward a photon target disposed at the sensing cylinder rod, and a photon receiver coupled to the sensing cylinder base and configured to receive the photon reflected from the photon target. The processor is configured to determine a stroke of the cylinder based on a time of flight of the photon from the photon emitter to the photon receiver.

A cylinder stroke determination system and a method of determining a stroke of a cylinder are provided. The system includes a cylinder having a rod and a barrel, a sensing cylinder configured to operate with the cylinder, and a processor. The sensing cylinder includes a sensing cylinder base coupled to the barrel of the cylinder, a sensing cylinder rod coupled to the connecting portion of the rod of the cylinder, a photon emitter coupled to the sensing cylinder base and configured to emit a photon toward a photon target disposed at the sensing cylinder rod, and a photon receiver coupled to the sensing cylinder base and configured to receive the photon reflected from the photon target. The processor is configured to determine a stroke of the cylinder based on a time of flight of the photon from the photon emitter to the photon receiver.

Provided is a compression ratio varying mechanism, including a communication hole including: a first opening opened in an outer peripheral side surface of a piston rod; and a second opening, which is prevented from being opposed to the first opening in a radial direction of a piston rod, and is connected to an oil passage at a position apart from the first opening in a stroke direction.

Provided is a compression ratio varying mechanism, including a communication hole including: a first opening opened in an outer peripheral side surface of a piston rod; and a second opening, which is prevented from being opposed to the first opening in a radial direction of a piston rod, and is connected to an oil passage at a position apart from the first opening in a stroke direction.

A power tool includes a housing, a motor, and a drive mechanism. The drive mechanism includes a driven gear that is rotated by the motor. The driven gear is vertically-oriented within the housing and has an upper portion and a lower portion. The drive mechanism also includes a connecting rod coupled to the driven gear to translate rotary motion of the driven gear into reciprocating motion, and an output shaft coupled to the connecting rod to reciprocate relative to the housing through a cutting stroke and a return stroke. The drive mechanism further includes a counterweight coupled to the driven gear for rotation with the driven gear. The counterweight moves through the upper portion of the driven gear during the cutting stroke of the output shaft, and moves through the lower portion of the driven gear during a return stroke of the output shaft.

A power tool includes a housing, a motor, and a drive mechanism. The drive mechanism includes a driven gear that is rotated by the motor. The driven gear is vertically-oriented within the housing and has an upper portion and a lower portion. The drive mechanism also includes a connecting rod coupled to the driven gear to translate rotary motion of the driven gear into reciprocating motion, and an output shaft coupled to the connecting rod to reciprocate relative to the housing through a cutting stroke and a return stroke. The drive mechanism further includes a counterweight coupled to the driven gear for rotation with the driven gear. The counterweight moves through the upper portion of the driven gear during the cutting stroke of the output shaft, and moves through the lower portion of the driven gear during a return stroke of the output shaft.

A connecting rod assembly has a connecting rod with a large end and a small end, a piston wrist pin, and fasteners to connect the connecting rod to the piston wrist pin and optionally one or more shims in between the connecting rod and piston wrist pin. A notch on the wrist pin allows for the seating of a flat surface on the small end of the connecting rod in the connecting rod assembly. Side walls on both the notch and the small end of the connecting rod limit twist. The connecting rod assembly allows for the adjustment of piston location in a cylinder while limiting connecting rod twist.

A connecting rod assembly has a connecting rod with a large end and a small end, a piston wrist pin, and fasteners to connect the connecting rod to the piston wrist pin and optionally one or more shims in between the connecting rod and piston wrist pin. A notch on the wrist pin allows for the seating of a flat surface on the small end of the connecting rod in the connecting rod assembly. Side walls on both the notch and the small end of the connecting rod limit twist. The connecting rod assembly allows for the adjustment of piston location in a cylinder while limiting connecting rod twist.

A piston for a cylinder, and a method of fabrication thereof, the piston rod comprising a substrate and a coating, the substrate having a surface roughness profile comprising peaks and valleys with a peak-to-valley height in a range between 0.5 and 2 m, and the coating having a hardness in a range between 1000 and 4000 HV and a coefficient of friction in a range between 0.1 and 0.05.