Robotic work tool with height adjustable cutting disk and method for operating a robotic work tool

Patent metadata

Field	Value
Publication number	US-12256669-B2
Application number	US-202117525038-A
Country	US
Kind code	B2
Filing date	Nov 12, 2021
Priority date	Nov 13, 2020
Publication date	Mar 25, 2025
Grant date	Mar 25, 2025

Abstract

A robotic work tool ( 1 ) includes a cutting disk ( 6 ), which is rotatable and height adjustable. The robotic work tool ( 1 ) is configured to obtain a final desired cutting height of the cutting disk ( 6 ); determine a first cutting height, based at least on the final desired cutting height; raise the cutting disk ( 6 ) to an elevated position above the first cutting height; start a rotation of the cutting disk ( 6 ); and lower the cutting disk ( 6 ) to the determined first cutting height.

First claim

The invention claimed is:

1. A robotic work tool comprising a cutting disk, which is rotatable and height adjustable, the robotic work tool being configured to:
obtain a final desired cutting height of the cutting disk;
determine a first cutting height, based at least on the final desired cutting height;
raise the cutting disk to an elevated position above the first cutting height;
start a rotation of the cutting disk while the cutting disk is in the elevated position; and
lower the cutting disk to the determined first cutting height, in response to the cutting disk has obtained a substantially full rotational cutting speed.

2. The robotic work tool according to claim 1 , wherein the robotic work tool is configured to raise the cutting disk to the elevated position before lowering a rotational speed of the cutting disk.

3. The robotic work tool according to claim 1 , wherein the robotic work tool is configured to raise the cutting disk to the elevated position after a cutting session has been completed.

4. The robotic work tool according to claim 1 , wherein the robotic work tool is configured to raise the cutting disk to the elevated position before a cutting session starts.

5. The robotic work tool according to claim 1 , wherein the robotic work tool comprises an elevation means arranged to automatically raise and lower the cutting disk.

6. The robotic work tool according to claim 1 , wherein the robotic work tool is configured to activate an indicator before the cutting disk is lowered.

7. The robotic work tool according to claim 6 , wherein activation of the indicator includes sounding an alarm signal.

8. The robotic work tool according to claim 1 , wherein the elevated position is 5-10 mm above the determined first cutting height.

9. The robotic work tool according to claim 1 , wherein the cutting disk includes rotatable knives.

10. The robotic work tool according to claim 1 , wherein the robotic work tool is configured to have a regular mode and a low mode and configured to raise the cutting disk to the elevated position in the low mode only.

11. The robotic work tool according to claim 1 , wherein the robotic work tool is configured to:
determine one or more further cutting heights below the first cutting height based at least on the final desired cutting height;
determine the elevated position to 5-10 mm above the further cutting height;
raise the cutting disk to the elevated position;
start the rotation of the cutting disk; and
lower the cutting disk to the determined further cutting height.

12. A method for running a robotic work tool, comprising the steps of:
obtaining a final desired cutting height;
determining a first cutting height, based at least on the final desired cutting height;
raising a cutting disk to an elevated position above the first cutting height;
starting a rotation of the cutting disk while the cutting disk is in the elevated position; and
lowering the cutting disk to the determined first cutting height, in response to the cutting disk has obtained a substantially full rotational cutting speed.

Assignees

• Husqvarna Ab

Inventors

• Forsman Pär

Classifications

• A01D2101/00

  Lawn-mowers · CPC title

• A01D75/18

  Safety devices for parts of the machines · CPC title

• A01D34/64

  mounted on a vehicle, e.g. a tractor, or drawn by an animal or a vehicle (A01D34/695 takes precedence) · CPC title

• A01D34/008 Primary

  for automated or remotely controlled operation · CPC title

• A01B39/18

  for weeding · CPC title