Patent ID: 11945092
Assignee: MAKITA CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 15:
16. A power tool, comprising:
a motor;
a reducer configured to reduce rotation from the motor, the reducer including
at least two stages of internal gears aligned in an axial direction,
a preceding planetary gear in a preceding stage,
a succeeding planetary gear in a succeeding stage adjacent to the preceding planetary gear in the axial direction, the preceding planetary gear and the succeeding planetary gear being configured to revolve within and engage the internal gears, and
at least two stages of gear carriers aligned in the axial direction, a gear carrier of the gear carriers supporting the preceding planetary gear and the succeeding planetary gear radially overlapping with a single pin; and

an actuator configured to be actuated by the rotation reduced by the reducer, wherein
the internal gears include a preceding internal gear in the preceding stage meshing with the preceding planetary gear and a succeeding internal gear in the succeeding stage meshing with the succeeding planetary gear,
the preceding internal gear and the succeeding internal gear are adjacent in the axial direction,
the reducer includes a seal between a facing surface of the preceding internal gear and a facing surface of the succeeding internal gear,
the preceding internal gear includes a first flange protruding radially inward at an end opposite to the facing surface of the preceding internal gear,
the succeeding internal gear includes a second flange protruding radially inward at an end opposite to the facing surface of the succeeding internal gear,
the preceding internal gear and the succeeding internal gear are rotatable,
the power tool further comprises a rotation restrictor configured to selectively restrict rotation of the preceding internal gear and the succeeding internal gear,
the rotation restrictor includes:
an engagement member (i) radially outward from the preceding internal gear and the succeeding internal gear and (ii) being switchable between a first position and a second position; and
an operation unit operable to switch the engagement member selectively to either the first position or the second position,

the engagement member, the preceding internal gear and the succeeding internal gear are configured such that:
the engagement member is engaged with the preceding internal gear and configured to restrict rotation of the preceding internal gear when the engagement member is in the first position; and
the engagement member is engaged with the succeeding internal gear and configured to restrict rotation of the succeeding internal gear when the engagement member is in the second position,
the engagement member has a middle portion that is supported and two ends that are swingable,
a first end of the two ends is engaged with an outer circumference of the preceding internal gear, when the engagement member is in the first position,
a second end of the two ends is engaged with an outer circumference of the succeeding internal gear when the engagement member is in the second position,
the reducer is housed in a cylindrical case, and
the operation unit includes
an annular member rotatably on an outer circumference of the case and including a first pressing portion and a second pressing portion alternating circumferentially, the first pressing portion being configured to press the first end of the engagement member from outside in a radial direction of the case to switch the engagement member to the first position, the second pressing portion being configured to press the second end of the engagement member from outside in the radial direction to switch the engagement member to the second position, and
a rotational operation member configured to rotate the annular member on the outer circumference of the case by a predetermined angle.