Router with dust suction hood
AssigneeBlack & Decker Inc.
InventorYuejun Qian
Life of this patent
Estimating the term…
Abstract
A device for cutting a workpiece by means of a rotatingly driven tool bit has a suction hood surrounding the tool bit in annular manner with a through-opening for the tool bit to pass through. The suction hood forms a suction duct open to the tool bit which is limited by an outer wall. At least a part of the outer wall is curved in a perpendicular plane in the form of a parabola, and the focal point of the parabola lies beneath the workpiece engagement surface formed by the suction hood. Because of this parabola shape, chips thrown by the tool bit against the outer wall are reflected essentially parallel to the workpiece engagement surface and thus do not escape up through the through-opening.
Claims6
A device for cutting a workpiece with a tool bit rotatingly driven about an axis in a working rotation direction comprising:
- a head for supporting and rotatably driving the tool bit;
- an annular suction hood surrounding the tool bit;
- the suction hood comprising:
- a top wall;
- a workpiece engaging wall;
- an outer wall extending between the top wall and the workpiece engaging wall;
- a through-opening formed in the workpiece engaging wall and permitting the tool bit to pass therethrough with a clearance width that is a multiple of the diameter of the tool bit;
- a suction duct open to the tool bit;
- at least a part-zone of the outer wall curved over at least a part of the circumference of the through opening in a plane extending parallel to the rotation axis of the tool bit and intersecting the outer wall at two points spaced from each other;
- and
- the part-zone having a parabolic curve defining a parabola with a focal point located between outer wall sections lying opposite each other and at a lesser distance from the workpiece engagement wall than from the top wall of the suction hood.
Dependencies are inferred from the claim text.