A reciprocating saw includes a housing, a motor, and a drive mechanism. The motor includes an output gear rotatable about a motor axis. The drive mechanism includes a driven gear that engages the output gear and is rotated by the motor. The driven gear has a circumference and is vertically-oriented within the housing. The drive mechanism also includes an output shaft coupled to the driven gear and configured to reciprocate relative to the housing. The drive mechanism further includes a single counterweight fixed relative to the driven gear and rotating with the driven gear through a path and in a same direction. As the counterweight moves through a rearward half of the path, the counterweight generally moves in an upward direction, and as the counterweight moves through a forward half of the path, the counterweight generally moves in a downward 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 for an internal combustion engine may include a connecting rod shank, a large connecting rod eye, and a small connecting rod eye with a pin bore. An end face of the small connecting rod eye may also include at least one overhang, the overhang running parallel to a central axis of the pin bore over its entire width transverse to the central axis of the pin bore. An edge of the overhang may also run parallel to the central axis of the pin bore.

A connecting rod for an internal combustion engine may include a connecting rod shank, a large connecting rod eye, and a small connecting rod eye with a pin bore. An end face of the small connecting rod eye may also include at least one overhang, the overhang running parallel to a central axis of the pin bore over its entire width transverse to the central axis of the pin bore. An edge of the overhang may also run parallel to the central axis of the pin bore.

The present invention relates to a connecting rod comprising a small spherical end having a ball and a main rod. The ball and the main rod are designed as individual parts and form, when assembled, a connecting rod having a spherical small end.

The present invention relates to a connecting rod comprising a small spherical end having a ball and a main rod. The ball and the main rod are designed as individual parts and form, when assembled, a connecting rod having a spherical small end.

A piston is provided for an internal combustion engine. The piston may include a cylindrical first piston portion having a first diameter, a cylindrical second piston portion of the first diameter, and a cylindrical third piston portion of a second diameter less than the first diameter located between the first piston portion and the second piston portion. The first piston portion may be configured such that prior to assembly, the first piston portion is separate from the second piston portion. The piston may also include a continuous, gapless piston ring circumscribing the third piston portion, where the piston ring may be configured such that when heated the piston ring deforms in an axial direction of the piston.

A piston is provided for an internal combustion engine. The piston may include a cylindrical first piston portion having a first diameter, a cylindrical second piston portion of the first diameter, and a cylindrical third piston portion of a second diameter less than the first diameter located between the first piston portion and the second piston portion. The first piston portion may be configured such that prior to assembly, the first piston portion is separate from the second piston portion. The piston may also include a continuous, gapless piston ring circumscribing the third piston portion, where the piston ring may be configured such that when heated the piston ring deforms in an axial direction of the piston.

An assembly including a connecting rod, a bushing, and a locking pin capable of providing different compression ratios in an engine is provided. The bushing is disposed in a bore of the connecting rod. An outer surface of the bushing includes a pair of notches, and an inner surface of the connecting rod includes a corresponding notch for receiving the locking pin. The notches are spaced from one another by greater than 180 and by no more than 190. The locking pin is movable in the notch, allowing the bushing to rotate from a low compression position to a high compression position, or vice versa. The bushing has a varying thickness, and thus a center axis of an opening of the bushing is closer to the shaft of the connecting rod body when the bushing is in the low compression orientation than in the high compression orientation.