Land levelling device

• US 6,467,552 B1
• Filed: 06/05/2001
• Issued: 10/22/2002
• Est. Priority Date: 05/28/1999
• Status: Expired due to Fees

• Current Assignee: Newman Engineering (2004) Limited (RCR Tomlinson Limited)
• Original Assignee: Harry Ross Whatmough
• Inventors: Whatmough, Harry Ross
• Primary Examiner(s): PEZZUTO, ROBERT ERIC
• Application Number:
  US09/874,782
• Time in Patent Office: 504 Days
• Field of Search: 172/449, 172/605, 172/439, 172/445.1, 172/501, 172/503, 172/684.5, 172/777, 172/448, 172/502, 172/299, 172/824-826, 172/239, 172/197, 172/199, 172/145, 403/3, 403/4
• US Class Current: 172/445.1
• CPC Class Codes: A01B 31/00 Drags graders for field cultivators graders in general E02F
• CPC Class Codes: E02F 3/7622 Scraper equipment with the scraper blade mounted on a frame to be hitched to the tractor by bars, arms, chains or the like, the frame having no ground supporting means of its own, e.g. drag scrapers

Abstract

Preferably the land levelling device (1) includes a support frame (2) on which is mounted a front, transversely extending, blade (3), a rear, transversely extending, blade (4), and a coupler (5) for, in use, attaching the land levelling device to a towing vehicle (30), the support frame (2) mounting the front and rear blades (3, 4) in substantially parallel spaced apart relationship wherein the front blade (3) has a cutting edge (9) projecting foremost, and a cutting face (10) angled backwardly and upwardly from the cutting edge (9) toward the support frame (2), and wherein the rear blade (4) has a lower edge (13) which lies below, or at least co-planar with, the cutting edge (9) of the front blade (3), the construction and arrangement of the front and rear blades (3, 4) being such that in use mounds or bumps in the ground are sheared off by the front blade (3) and pass over it to be redistributed into hollows in the ground by the rear blade (4).

Claims

1. A land levelling device comprising:

a support frame;

a front, transversely extending blade mounted to the support frame;

a rear, transversely extending blade mounted to the support frame; and

a coupler adapted for attaching the land levelling device to a towing vehicle.,

wherein the support frame mounts the front and rear blades in substantially parallel spaced apart relationship,

wherein said front blade has a cutting edge projecting foremost, and a cutting face angled backwardly and upwardly from the cutting edge toward the support frame, and wherein said rear blade has a lower edge not extending above a substantially horizontal plane defined by the cutting edge of the front blade, the construction and arrangement of the front and rear blades being such that in use mounds or bumps in the ground are sheared off by the front blade and pass over it to be redistributed into hollows in the ground by the rear blade.

2. A land levelling device according to claim 1 wherein the front blade is oriented at an angle of between 20 degrees and 50 degrees from the horizontal upwardly and rearwardly away from the cutting edge.

3. A land levelling device according to claim 2 wherein the front blade is oriented at an angle of 30 degrees from the horizontal upwardly and rearwardly away from the cutting edge.

4. A land levelling device according to claim 1, wherein the front blade is configured and arranged to provide a ramped surface so that, in use, earth cut by the cutting edge is separated from the ground beneath and is lifted up the ramped surface by the forward motion of the land levelling device and dumped in front of the oncoming rear blade.

5. A land levelling device according to claim 1, wherein the cutting edge of the front blade and the lower edge of the rear blade are co-planar.

6. A land levelling device according to claim 1, wherein the lower edge of the rear blade projects downwardly of the support frame beyond the cutting edge of the front blade.

7. A land levelling device according to claim 1, wherein the land levelling device further includes a levelling plate mounted from the bottom edge of the rear blade.

8. A land levelling device according to claim 1, wherein the land levelling device further includes a rear wall upstanding from the rear blade to, in use, trap earth cut by the front blade and hold it available for redistribution by the levelling plate of the rear blade.

9. A land levelling device according to claim 8, wherein the land levelling device further includes upstanding side walls extending between the corresponding ends of the front and rear blades, the side walls being attached, one at each end, to the rear wall.

10. A land levelling device according to claim 1, wherein the coupler is configured and arranged to enable, in use, attachment of the land levelling device to a three-point linkage of a towing vehicle.

11. A land levelling device according to claim 3, wherein the front blade is configured and arranged to provide a ramped surface so that, in use, earth cut by the cutting edge is separated from the ground beneath and is lifted up the ramped surface by the forward motion of the land levelling device and dumped in front of the oncoming rear blade.

12. A land levelling device according to claim 11, wherein the cutting edge of the front blade and the lower edge of the rear blade are co-planar.

13. A land levelling device according to claim 12, wherein the lower edge of the rear blade projects downwardly of the support frame beyond the cutting edge of the front blade.

14. A land levelling device according to claim 13, wherein the land levelling device further includes a levelling plate mounted from the bottom edge of the rear blade.

15. A land levelling device according to claim 14, wherein the land levelling device further includes a rear wall upstanding from the rear blade to, in use, trap earth cut by the front blade and hold it available for redistribution by the levelling plate of the rear blade.

16. A land levelling device according to claim 15, wherein the land levelling device further includes upstanding side walls extending between the corresponding ends of the front and rear blades, the side walls being attached, one at each end, to the rear wall.

17. A land levelling device according to claim 1, wherein the coupler is configured and arranged to enable, in use, attachment of the land levelling device to a three-point linkage of a towing vehicle.