Back to results
US 10,259,060 B2Granted
Reciprocating tool
AssigneeMakita Corporation
InventorsYudai Sugino, Tomohiro Ukai
Life of this patent
Estimating the term…
Abstract
A reciprocating tool includes a motor, a crank, a connecting rod, a rod, a tool bit, and a counter weight. The tool bit is mounted such that the action portion is positioned on a side opposite to a side with the rod central axis or the extended line of the rod central axis viewing from the rotational center of the crank. The first eccentric shaft and the second eccentric shaft are disposed such that at a position where the first eccentric shaft causes the rod to reach top dead center (TDC), the second eccentric shaft causes the counter weight to reach bottom dead center (BDC) or a point before the BDC, and at a position where the first eccentric shaft causes the rod to reach the BDC, the second eccentric shaft causes the counter weight to reach a point before the TDC.
Claims20
A reciprocating tool comprising,
- a motor;
- a first crank and a second crank rotated by the motor;
- a connecting rod coupled to (a) a first eccentric shaft of the first crank and (b) a first eccentric shaft portion of the second crank, the first eccentric shaft being disposed eccentrically relative to a rotational center of the first crank and the first eccentric shaft portion being disposed eccentrically relative to a rotational center of the second crank;
- a rod coupled to the connecting rod;
- a tool bit with an action portion, the tool bit being mounted on the rod;
- a first counter weight coupled to a second eccentric shaft of the first crank, the second eccentric shaft being disposed eccentrically relative to the rotational center of the first crank;
- and
- a second counter weight coupled to a second eccentric shaft portion of the second crank, the second eccentric shaft portion being disposed eccentrically relative to the rotational center of the second crank;
- wherein
- the second crank is separate from the first crank, the second counter weight is separate from the first counter weight, and the second eccentric shaft is separate from the second eccentric shaft portion,
- top dead center (TDC) is a frontmost position and bottom dead center (BDC) is a rearmost position of a range of movement of the first counter weight and the second counter weight in a front-rear direction,
- the rotational centers of the first crank and the second crank are not disposed on an extended line of a central axis of the rod,
- the tool bit is mounted such that the action portion is positioned on a side opposite to a side on which the rod is coupled to the connecting rod,
- the first eccentric shaft, the second eccentric shaft, the first eccentric shaft portion and the second eccentric shaft portion are disposed such that,
- at a position where the first eccentric shaft and the first eccentric shaft portion cause the rod to reach the TDC, the second eccentric shaft and the second eccentric shaft portion cause the first and second counter weights to reach the BDC or a point before the BDC, and
- at a position where the first eccentric shaft and the first eccentric shaft portion cause the rod to reach the BDC, the second eccentric shaft and the second eccentric shaft portion cause the first and second counter weights to reach a point before the TDC, and
- the first crank and the first counter weight are located on one side of the central axis of the rod and the second crank and second counter weight are located on a side of the central axis of the rod that is opposite to the first side.
14 more elements
A reciprocating tool having a longitudinal axis, comprising:
- a motor;
- a crank that has (1) a disc shape, (2) opposing side faces that are parallel to the longitudinal axis of the reciprocating tool, (3) a rotational axis that is perpendicular to the longitudinal axis, and (4) a first eccentric shaft and a second eccentric shaft each (a) protruding from the opposing side faces perpendicular to the longitudinal axis and (b) having a central axis that is parallel to and offset from the rotational axis of the crank;
- a connecting rod coupled to the first eccentric shaft of the crank;
- a rod extending parallel to the longitudinal axis and rotatably coupled to the connecting rod;
- a tool bit with an action portion, the tool bit being mounted to the rod;
- and
- a counter weight coupled to the second eccentric shaft of the crank;
- wherein:
- the crank is rotated around the rotational axis by the motor,
- the rotational axis of the crank is not disposed on an extended line of a center axis of the rod,
- the first eccentric shaft and the second eccentric shaft are disposed such that:
- at a position where the first eccentric shaft causes the rod to reach a top dead center, the second eccentric shaft causes the counter weight to reach a bottom dead center or a point before the bottom dead center, and
- at a position where the first eccentric shaft causes the rod to reach the bottom dead center, the second eccentric shaft causes the counter weight to reach a point before the top dead center,
- the first eccentric shaft moves the rod back and forth via the connecting rod when the crank rotates,
- the central axis of the first eccentric shaft and the central axis of the second eccentric shaft are disposed on opposite sides of the rotational axis of the crank,
- the first eccentric shaft and the second eccentric shaft protrude in opposite directions from the crank, and
- the second eccentric shaft moves the counter weight back and forth when the crank rotates, and the second eccentric shaft moves in an arc shape on an upper half portion of the crank when the counter weight moves from the bottom dead center to the top dead center.
14 more elements
A reciprocating tool having a longitudinal axis, comprising:
- a motor;
- a crank that has (1) a disc shape, (2) opposing side faces that are parallel to the longitudinal axis of the reciprocating tool, (3) a rotational axis that is perpendicular to the longitudinal axis, and (4) a first eccentric shaft and a second eccentric shaft each (a) protruding from the opposing side faces perpendicular to the longitudinal axis and (b) having a central axis that is parallel to and offset from the rotational axis of the crank;
- a connecting rod coupled to the first eccentric shaft of the crank;
- a rod that is rotatably coupled to the connecting rod and mounts a tool bit;
- and
- a counter weight coupled to the second eccentric shaft of the crank;
- wherein:
- the crank is rotated around the rotational axis by the motor,
- the rotational axis of the crank is not disposed on an extended line of a center axis of the rod,
- the first eccentric shaft and the second eccentric shaft are disposed such that:
- at a position where the first eccentric shaft causes the rod to reach a top dead center, the second eccentric shaft causes the counter weight to reach a bottom dead center or a point before the bottom dead center, and
- at a position where the first eccentric shaft causes the rod to reach the bottom dead center, the second eccentric shaft causes the counter weight to reach a point before the top dead center,
- the first eccentric shaft moves the rod back and forth via the connecting rod when the crank rotates,
- the central axis of the first eccentric shaft and the central axis of the second eccentric shaft are disposed on opposite sides of the rotational axis of the crank, and
- the second eccentric shaft moves in an arc and moves the counter weight back and forth when the crank rotates such that the counter weight moves between the bottom dead center and the top dead center,
- the first eccentric shaft and the second eccentric shaft protrude in opposite directions from the crank, and
- when the rod is positioned at the top dead center, an angle defined by (a) a line connecting the rotational axis of the crank to the central axis of the first eccentric shaft and (b) a line passing through the rotational axis of the crank and extending parallel to the longitudinal axis is larger than an angle defined by (a) a line connecting the rotational axis of the crank to the central axis of the second eccentric shaft and (b) a line passing through the rotational axis of the crank and extending parallel to the longitudinal axis.
14 more elements
Dependencies are inferred from the claim text.