Mowing blades having an impact energy absorbing structure

• US 6,938,402 B2
• Filed: 11/01/2002
• Issued: 09/06/2005
• Est. Priority Date: 11/01/2002
• Status: Expired due to Fees

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Hopkins, John W., Arfstrom, Jack E., Pahl, David J.
• Primary Examiner(s): Kovács, Árpád Fab
• Application Number:
  US10/285,864
• Publication Number:
  US 20040083700A1
• Time in Patent Office: 1,040 Days
• Field of Search: D15 14- 17, 302/76, 303/47, 303/90, 562/55, 562/95, 562/89
• US Class Current: 56/295
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/73 Cutting apparatus

Abstract

Mowing blades which include a one-piece member having a drive mechanism coupling section, a deformation section and a cutting section. When the mowing blades receive a particular load from an obstructing object, the deformation section deforms, dissipates energy and reduces damage to drive mechanisms of mowing machines.

Claims

1. A cutting blade comprising:

a one-piece member having;

(a) a drive mechanism coupling section having a width, a beginning point and an ending point, the drive mechanism coupling section extending from said beginning point radially outwardly to said ending point;

(b) a deformation section; and

(c) a cutting section having a width, a beginning point and an ending point, the cutting section extending from said beginning point radially outwardly to said ending point, the deformation section being positioned between the ending point of the drive mechanism coupling section and the beginning point of the cutting section, a portion of the deformation section having a width that is;

(i) less than the width of the drive mechanism coupling section; and

(ii) less than the width of the cutting section, the deformation section positioning the drive coupling section and the cutting section in different planes.

2. The cutting blade of claim 1, wherein the deformation section has an energy dissipating deformation structure.

3. The cutting blade of claim 1, wherein the deformation section defines a lever arm which facilitates deformation of the cutting blade in response to a force received by the cutting section.

4. The cutting blade of claim 1, wherein the portion has at least one geometric irregularity, the geometric irregularity including a wall selected from the group consisting of a wall defining a square notch, a wall defining a rounded notch, a wall defining a smooth notch and a wall defining a void.

5. The cutting blade of claim 4, wherein the geometric irregularity has an arc shape.

6. The cutting blade of claim 1, wherein the the portion has:

(a) one end substantially positioned in the same plane as the drive coupling section; and

(b) another end substantially positioned in the same plane as the cutting section.

7. The cutting blade of claim 1, wherein the deformation section has a width which is:

(a) less than the width of the drive mechanism coupling section; and

(b) less than the width of the cutting section.

8. The cutting blade of claim 7, wherein the widths of the drive mechanism coupling section and cutting section are substantially equal.

9. The cutting blade of claim 1, wherein the cutting blade has a parabolic shape.

10. The cutting blade of claim 1, which includes a plurality of side walls extending from the ending point of the drive mechanism coupling section to the beginning point of the cutting section, each of said side walls defining a cross-sectional parabolic shape.

11. The cutting blade of claim 1, wherein the drive mechanism coupling section, the deformation section and the cutting section are all made of the same material.

12. The cutting blade of claim 1, wherein the cutting blade is a mowing blade.

13. The cutting blade of claim 1, wherein the drive mechanism coupling section is adapted to be operatively coupled to a machine selected from the group consisting of a mower, a tractor, a trimmer and an edger.

14. A cutting blade connectable to a drive mechanism of a machine, the cutting blade having at least one end, the cutting blade comprising:

a drive mechanism coupling section having a width, a beginning point and an ending point, the drive mechanism coupling section extending from said beginning point, toward the end of the cutting blade, to said ending point;

a cutting section having a width, a beginning point and an ending point, the cutting section extending from said beginning point, toward the end of the cutting blade, to said ending point; and

at least one intermediate section positioned between the ending point of the drive mechanism coupling section and the beginning point of the cutting section, the intermediate section having a maximum width which is;

(a) less than the width of the drive mechanism coupling section; and

(b) less than the width of the cutting section, the intermediate section positioning the drive mechanism coupling section and the cutting section in different planes, the intermediate section operable to facilitate deformation of the cutting blade in response to a force received by the cutting section, thereby reducing damage to the drive mechanism of the machine.

15. The cutting blade of claim 14, wherein the intermediate section has at least one wall defining at least one geometric irregularity.

16. The cutting blade of claim 14, wherein the intermediate section has a ramp portion.

17. The cutting blade of claim 14, wherein the intermediate section has a position in a plurality of planes.

18. The cutting blade of claim 14, wherein the intermediate section defines a lever arm which facilitates deformation of the cutting blade in response to a force received by the cutting section.

19. The cutting blade of claim 14, wherein the intermediate section, the drive mechanism coupling section and the cutting section are integrated into one-piece member.

20. The cutting blade of claim 14, wherein the drive mechanism coupling section is adapted to be operatively coupled to a machine selected from the group consisting of a mower, a tractor, a trimmer and an edger.

21. A cutting blade connectable to a drive mechanism of a machine, the cutting blade having at least one end, the cutting blade comprising:

a drive mechanism coupling section having a beginning point and an ending point, the drive mechanism coupling section extending from said beginning point, toward the end of the cutting blade, to said ending point;

a cutting section having a beginning point and an ending point, the cutting section extending from said beginning point, toward the end of the cutting blade, to said ending point; and

at least one intermediate section extending from the ending point of the drive mechanism coupling section to the beginning point of the cutting section, the intermediate section having an upper surface, a lower surface and a plurality of side walls, each of the side walls defining a notch, each of the notches having a length extending from one end to another end, the intermediate section operable to position;

(a) the drive mechanism coupling section in a first plane; and

(b) the cutting section in a second plane located below the first plane, wherein, for each of the notches, one end of the notch is substantially positioned in the first plane and the other end of the notch is substantially positioned in the second plane, the intermediate section facilitating deformation of the cutting blade in response to a force received by the cutting section, thereby reducing damage to the drive mechanism of the machine.

22. The cutting blade of claim 21, wherein each of the notches has a shape selected from the group consisting of an arc shape, a rounded shape, a smooth shape, a square shape and a rectangular shape.