Vegetation cutter
AssigneeBlack & Decker Inc.
InventorBrian C. R. Henning
Life of this patent
Estimating the term…
Abstract
The invention is directed to an air cushion supported vegetation cutter including a cutter casing housing an impeller for creating the air cushion in conjunction with the casing. An aperture in the casing permits air flow to the impeller and a support structure supports a motor for driving the impeller. The support structure provides a duct for the flow of cooling air over the motor and the duct has cooling air outlets located upstream of the aperture in the casing. This arrangement provides an improved motor cooling arrangement in which the motor cooling air and the air for the impeller interact upstream of the impeller.
Claims16
An air cushion supported vegetation cutter comprising:
- a casing having an opening therein;
- an impeller housed in sid casing for drawing a flow of air through said opening to create an air cushion in conjunction with said casing;
- a motor for driving said impeller;
- and
- a support structure for supporting said motor and defining a duct for the flow of cooling air over said motor, said duct having cooling air outlet means located upstream in the air flow to said opening whereby said motor cooling air combines with and forms part of the air drawn by said impeller before the combined air is drawn through said opening.
An air cushion supported vegetation cutter, comprising:
- a casing having an opening therein;
- an impeller housed in said casing for receiving air through said opening to create an air cushion in conjunction with said casing;
- a motor for driving said impeller;
- support means enclosing said motor and having air inlet means and air outlet means to permit cooling air to flow past said motor from said inlet means to said outlet means for cooling said motor;
- first duct means having first aperture means at one end to permit entry of air, and communicating at the other end with said opening for supplying the air thereto, said outlet means communicating with said first duct means whereby the motor cooling air combines with the air in said first duct means before passing through said opening;
- and
- said first aperture means being so dimensioned that in operation it restricts the necessary flow of air to said impeller creating a pressure drop adjacent said outlet means to promote an increase in the flow of cooling air past said motor.
Dependencies are inferred from the claim text.