Patent ID: 11883941
Assignee: MAKITA CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. A hammer drill comprising:
a housing; and
a motor having an output shaft with a rotation axis in a front-rear direction, a driving mechanism including a tubular tool holder and a rotation conversion member, an inner housing and a seal member inside the housing, wherein
the tool holder has a distal end and is rotatable with a bit mounted on the distal end,
the driving mechanism is configured to perform at least one of rotation actuation of the tool holder and hammering actuation of the bit using power from the motor,
the rotation conversion member is configured to convert rotation of the output shaft of the motor to the hammering actuation of the bit,
the inner housing supports the tool holder via a first bearing and the output shaft via a second bearing,
the inner housing includes (i) an integral, one-piece front housing holding the first bearing and (ii) a rear housing that is a separate body from the front housing and holds the second bearing,
the front housing is in front of the rear housing in the front-rear direction,
the front housing is connected to the rear housing in the front-rear direction,
the seal member (i) is between the inner housing and the housing and (ii) seals a space between the inner housing and the housing, and
the seal member, the inner housing and the housing are configured such that (i) a grease chamber is defined by a front side of the seal member in the front-rear direction, the inner housing and the housing and (ii) an air cooling chamber is defined by a rear side of the seal member in the front-rear direction, the inner housing and the housing.