Rotary mower with cutting deck with bidirectional cutting blades

Patent metadata

Field	Value
Publication number	US-11730083-B2
Application number	US-202117195113-A
Country	US
Kind code	B2
Filing date	Mar 8, 2021
Priority date	Mar 9, 2020
Publication date	Aug 22, 2023
Grant date	Aug 22, 2023

Abstract

A rotary lawn mower has one or more grass cutting blades that are rotatable in opposite directions about a vertical axis or axes. Each blade is double edged having front and rear cutting edges on each end of the blade. Each blade end has a front sloped face inboard of the front cutting edge and a rear sloped face inboard of the rear cutting edge. These faces create air flow within the cutting chamber when cutting grass regardless of the direction of rotation of the blade. The direction of rotation of each blade is reversed to switch between discharge and mulching modes of operation. A flow director has a curved vertical guide wall that guides the grass clippings through a discharge opening in the discharge mode and that guides the flow of grass clippings away from the discharge opening in the mulching mode.

First claim

The invention claimed is:

1. A rotary lawn mower, which comprises:
(a) a cutting deck comprising a top wall and a peripheral skirt extending downwardly from the top wall, the top wall and peripheral skirt forming a cutting chamber having an open bottom face, the cutting chamber having a discharge opening located at least partially in the peripheral skirt of the cutting deck for allowing grass clippings to exit from the cutting chamber;
(b) at least one cutting blade located within the cutting chamber with the at least one cutting blade being rotatable about a substantially vertical axis of rotation, each end of the at least one cutting blade comprising:
(i) a front cutting edge and a rear cutting edge;
(ii) an upwardly raised, front sloped face inboard of the front cutting edge and an upwardly raised, rear sloped face inboard of the rear cutting edge; and
(iii) at least one opening located between the front and rear cutting edges and extending through a thickness of the at least one cutting blade to permit the passage of air through the at least one opening; and

(c) a reversible blade drive for allowing a user to select either:
(i) a discharge mode of operation in which the at least one cutting blade rotates in a first direction about the axis of rotation with the front cutting edges being leading edges and the rear cutting edges being trailing edges, or
(ii) a mulching mode of operation in which the at least one cutting blade rotates in a second opposite direction about the axis of rotation with the rear cutting edges being leading edges and the front cutting edges being trailing edges.

2. The mower of claim 1 , wherein, for each end of the at least one cutting blade, the at least one opening extends to a tip of the end of the cutting blade.

3. The mower of claim 2 , wherein the at least one opening comprises a radial slot.

4. The mower of claim 1 , wherein the front and rear sloped faces on each end of the at least one cutting blade are inboard of the front and rear cutting edges.

5. The mower of claim 1 , wherein the front and rear sloped faces have substantially the same angle of inclination as one another.

6. The mower of claim 1 , wherein the front and rear sloped faces have a substantially constant height relative to the front and rear cutting edges.

7. The mower of claim 1 , wherein the front sloped face has an inclination of at least approximately 60° at a tip of each end of the at least one cutting blade.

8. A rotary lawn mower, which comprises:
a cutting deck comprising a top wall and a peripheral skirt extending downwardly from the top wall, the top wall and peripheral skirt forming a cutting chamber having an open bottom face, the cutting chamber having a discharge opening located at least partially in the peripheral skirt of the cutting deck for allowing grass clippings to exit from the cutting chamber;
at least one cutting blade located within the cutting chamber with the at least one cutting blade being rotatable about a substantially vertical axis of rotation, each end of the at least one cutting blade comprising:
a front cutting edge and a rear cutting edge, and an upwardly raised, front sloped face inboard of the front cutting edge and an upwardly raised, rear sloped face inboard of the rear cutting edge, wherein the front sloped face is steeper than the rear sloped face; and
a reversible blade drive for allowing a user to select either:
a discharge mode of operation in which the at least one cutting blade rotates in a first direction about the axis of rotation with the front cutting edges being leading edges and the rear cutting edges being trailing edges, or
a mulching mode of operation in which the at least one cutting blade rotates in a second opposite direction about the axis of rotation with the rear cutting edges being leading edges and the front cutting edges being trailing edges.

9. The mower of claim 8 , wherein the front sloped face is at least approximately three times steeper than the rear sloped face at a tip of each end of the at least one cutting blade.

10. The mower of claim 9 , further including a raised ridge on each end of the at least one cutting blade located between the front and rear cutting edges, wherein the front sloped face is formed by a surface extending between the front cutting edge of the at least one cutting blade and a crest of the ridge, and the rear sloped face is formed by a surface extending between the rear cutting edge of the at least one cutting blade and the crest of the ridge.

11. The mower of claim 10 , wherein the ridge gradually decreases in height relative to the front and rear cutting edges as the ridge extends radially inwardly from the tip of each end of the at least one cutting blade.

12. The mower of claim 11 , wherein the ridge disappears at radial inner ends of the front and rear cutting edges.

13. The mower of claim 1 , wherein the at least one cutting blade comprises two or more blades with each blade being rotatable about its own separate substantially vertical axis of rotation.

14. A rotary lawn mower, which comprises:
a cutting deck comprising a top wall and a peripheral skirt extending downwardly from the top wall, the top wall and peripheral skirt forming a cutting chamber having an open bottom face, the cutting chamber having a discharge opening located at least partially in the peripheral skirt of the cutting deck for allowing grass clippings to exit from the cutting chamber;
at least one cutting blade located within the cutting chamber with the at least one cutting blade being rotatable about a substantially vertical axis of rotation, each end of the at least one cutting blade comprising:
a front cutting edge and a rear cutting edge, and an upwardly raised, front sloped face inboard of the front cutting edge and an upwardly raised, rear sloped face inboard of the rear cutting edge; and
a reversible blade drive for allowing a user to select either:
a discharge mode of operation in which the at least one cutting blade rotates in a first direction about the axis of rotation with the front cutting edges being leading edges and the rear cutting edges being trailing edges, or
a mulching mode of operation in which the at least one cutting blade rotates in a second opposite direction about the axis of rotation with the rear cutting edges being leading edges and the front cutting edges being trailing edges;

wherein the cutting chamber has a substantially vertical, curved guide wall therein adjacent the discharge opening, the guide wall presenting an outward curvature to grass clippings that have been generated in the discharge mode to direct such clippings outwardly through the discharge opening, and the guide wall further presenting an inward curvature to grass clippings that have been generated in the mulching mode to direct such clippings inwardly in the cutting chamber away from the discharge opening.

15. The mower of claim 14 , wherein the cutting chamber has a substantially horizontal floor along a bottom edge of the curved guide wall extending between the curved guide wall and the peripheral skirt of the cutting chamber.

16. The mower of claim 14 , wherein the guide wall and the floor are formed as part of a single piece flow director that is separate from the cutting deck, and further including fasteners for removably mounting the flow director to the cutting deck adjacent the discharge opening.

17. A rotary lawn mower, which comprises:
(a) a cutting deck comprising a top wall and a peripheral skirt extending downwardly from the top wall, the top wall and peripheral skirt for

Assignees

• The Toro Co

Inventors

• Henry Jason J
• Wadzinski Chris A

Classifications

• A01D42/005 Primary

  Mulching (shredders or like cutting implements for comminuting plant waste per se A01G3/002) · CPC title

• A01D34/76

  Driving mechanisms for the cutters · CPC title

• A01D34/667

  Means for directing the cut crop · CPC title

• A01D34/71

  with means for discharging mown material (A01D57/26 - A01D57/30 take precedence; combined with means for gathering or loading mown material A01D43/06) · CPC title

• A01D34/73

  Cutting apparatus · CPC title