Power tool having air discharge windows
AssigneeHitachi Koki Co., Ltd.
InventorsTomomasa Nishikawa, Shinki Ohtsu
Life of this patent
Estimating the term…
Abstract
A power tool providing a smooth cooling air flow discharging through discharge windows formed in a housing. In the housing a radial fan is rotatably provided for cooling a heated motor. A cooling air generated by the radial fan is discharged through the discharge windows. Each discharge window has a rectangular shape having an upstream side and a downstream side in the rotating direction of the cooling fan. A chamfered portion is provided at least at the upstream side and in an inner peripheral surface of the housing, so that a thickness of the housing wall is gradually small in the rotating direction. The chamfered portion increases an effective area of the window for discharging air.
Claims10
A power tool comprising:
- a housing having a part defining a fan chamber and having outer and inner circumferential surfaces, the part of the housing being formed with at least one discharge window extending in a circumferential direction of the housing for allowing air to pass therethrough from the fan chamber to an atmosphere;
- a motor disposed in the housing and comprising an armature and a stator, the motor being rotatable in a first rotating direction and a second rotating direction opposite to the first rotating direction;
- and
- a cooling fan connected to the armature and rotatable together with the armature, the cooling fan being disposed in the fan chamber;
- and
- wherein the at least one discharge window has a first side and a second side in opposition to the first side in the first and second rotating directions, the first side having a first slant wall portion at the inner circumferential surface to gradually reduce a thickness of the housing in the first rotating direction, and the second side having a second slant wall portion at the inner circumferential surface to gradually reduce a thickness of the housing in the second rotating direction.
Dependencies are inferred from the claim text.