Rotary lawn mower blade

• US 20050172601A1
• Filed: 05/20/2003
• Published: 08/11/2005
• Est. Priority Date: 05/21/2002
• Status: Abandoned Application

• Current Assignee: PBL SA
• Original Assignee: PBL SA
• Inventors: Besogne, Patrick
• Application Number:
  US10/514,731
• Publication Number:
  US 20050172601A1
• Time in Patent Office: Days
• US Class Current: 56/295
• CPC Class Codes: A01D 34/73 Cutting apparatus
• CPC Class Codes: A01D 34/826 Noise reduction means

Abstract

A lawn mower blade or the like consisting of a rectangular elongated and flattened plate (2) including in its center a bore (3) bordered on either side with holes (4) for its being fixed to a rotating drive shaft, the blade having a leading edge (7), a trailing edge (8) and a raised part (9) located proximate each end of the blade, while each leading edge (1) and trailing edge (8) has, relative to a horizontal plane containing the plate (2), a chamfered profile (6) which is provided with an angle (β) ranging between 0 and 30 degrees and the chamfered profile (6) includes a tapered terminal tip (10) whose land thickness d ranges between 0.1 and 0.5 millimeters.

Claims

1. Lawnmower blade or the like constituted by a plate (2) of elongated and flattened rectangular shape comprising at its middle a bore (3) bordered on opposite sides by holes (4) permitting its securement to a rotatable drive shaft, said blade comprising a leading edge (7), a trailing edge (8) and a raised portion (9) located adjacent each end of the blade, characterized in that each leading edge (7) and trailing edge (8) has, relative to a horizontal plane containing the plate (2), a beveled profile (6) which is provided with an inclination (β

) comprised between 0 and 30 degrees and in that the beveled profile (6) comprises a tapered end point (10) whose thickness d is comprised between 0.1 and 0.5 millimeter.

2. Lawnmower blade or the like according to claim 1, characterized in that the thickness d of the tapered point (10) is constant over all the length of the beveled edge (6) of the blade (1)

3. Lawnmower blade or the like according to claim 1, characterized in that the plate (2) comprises edges (11, 12) which are, relative to a horizontal plane containing said plate, inclined at an angle (α

) so as to constitute a blade (1) in the shape of a deformed parallelogram.

4. Lawnmower blade or the like according to claim 1, characterized in that the plate (2) comprises edges (11, 12) which are, relative to a vertical plane cutting said plate, inclined at an angle (δ

) such that the edges will be directed inwardly of the blade (9).

5. Lawnmower blade or the like according to claim 1, characterized in that the plate (2) comprises at each end a raised portion (9) which is more particularly provided at each trailing edge (8).

6. Lawnmower blade or the like according to claim 1, characterized in that each leading edge (7) comprises on its beveled profile (6) at least one notch (13).

7. Lawnmower blade or the like according to claim 1, characterized in that each trailing edge (8) comprises on its beveled profile (6) at least one notch (17).

8. Lawnmower blade or the like according to claim 6, characterized in that the notch (13) comprises a first flank (14) which is inclined at an angle (φ

) relative to a horizontal plane containing the leading edge (7) and a second flank (15) disposed perpendicularly to said edge, said flanks (14, 15) being connected to each other by a curved profile (16).

9. Lawnmower blade or the like according to claim 8, characterized in that the bottom of the notch (13) formed by the curved profile (16) is provided to be disposed at a certain distance from the horizontal axis of the plate (2).

10. Lawnmower blade or the like according to claim 7, characterized in that each trailing edge (8) comprises on each raised portion (9) a notch (17) having an inclined flank (18).

11. Lawnmower blade or the like according to claim 1, characterized in that it comprises at its trailing edge (8) and more particularly between its central bore (3) and its raised portion (9), a beveled edge (6) with an undulant profile constituted by other raised portions (19, 20) of different lengths and heights.

12. Lawnmower blade or the like according to claim 1, characterized in that it comprises a raised portion (9) whose inclination is variable or increasing from the trailing edge (8) to the center of the plate (2).