Autonomous lawn mower with recharge base

• US 7,668,631 B2
• Filed: 01/13/2009
• Issued: 02/23/2010
• Est. Priority Date: 01/23/2008
• Status: Expired due to Fees

• Current Assignee: Fabrizio Bernini
• Original Assignee: Fabrizio Bernini
• Inventors: Bernini, Fabrizio
• Primary Examiner(s): FABIAN-KOVACS, ARPAD
• Application Number:
  US12/352,882
• Publication Number:
  US 20090183478A1
• Time in Patent Office: 406 Days
• Field of Search: 701/23, 701/25, 701/207, 700/258, 180/168, 180/169, 180/167, 180/274, 180/279, 180/275, 180/277, 56/102.A, 56/102.F
• US Class Current: 701/23
• CPC Class Codes: A01B 69/008 automatic
• CPC Class Codes: A01D 34/008 for automated or remotely controlled operation
• CPC Class Codes: G05D 1/0265 using buried wires

Abstract

An apparatus for cutting grass in a cut area delimited by a perimeter, the perimeter being defined by the presence of regions of grass surface, comprises a lawn-mower and a lawn-mower-recovery base, the lawn-mower comprising a motor unit, a cutting device, the lawn-mower-recovery base being disposed along the perimeter with an accessible aperture allowing the entry of the lawn-mower moving along it, the lawn-mower further comprising a proximity sensor able to detect the presence of a grass surface, a control unit associated with the sensor, the control unit being configured to detect the perimeter, the control unit being configured to determine a condition of alignment of the lawn-mower with the perimeter, the control unit being operatively connected to the motor unit to cause a displacement of the lawn-mower along the same perimeter, to operate the return of the lawn-mower into the lawn-mower-recovery base.

Claims

1. Apparatus for cutting grass in a cut area delimited by a perimeter, said perimeter being defined by the presence of regions of grass surface having height lower or greater than a preset value,

said apparatus comprising a lawn-mower and a lawn-mower-recovery base, said lawn-mower comprising:

a motor unit for the directional displacement of said lawn-mower,

a cutting device,

said lawn-mower-recovery base being disposed along said perimeter of the cut area with an accessible aperture allowing the entry of the lawn-mower moving along said perimeter,

said lawn mower further comprising

at least a first proximity sensor able to detect the presence, if any, of a grass surface exceeding said height;

a control unit operatively associated with said first proximity sensor for receiving a signal therefrom, said control unit being configured to detect said perimeter according to said signal, said control unit being configured to determine a condition of alignment of said lawn-mower with said perimeter according to said signal,

said control unit being operatively connected to said motor unit to cause a displacement of the lawn-mower along said perimeter in response to the alignment condition to operate the return of said lawn-mower into the lawn-mower-recovery base.

2. Apparatus according to claim 1, wherein said lawn-mower comprises means for causing the lawn-mower to move in a preset direction of displacement along said perimeter.

3. Apparatus according to claim 1, wherein said lawn mower further comprises a second proximity sensor, said control unit being configured to operate said motor unit for keeping both sensors in proximity of the perimeter.

4. Apparatus according to claim 1, wherein said lawn-mower is a self-propelled, battery-rechargeable lawn-mower, and said lawn mower recovery-base is a recharge base provided with an electric connection to a power supply, and wherein said lawn mower recovery-base and said lawn-mower are provided with respective electric connections to establish an electric connection between said power supply and said lawn-mower and to carry out a recharge of batteries.

5. Apparatus according to claim 4, wherein said respective connections are preset for establishing said electric connection between the power supply and said lawn-mower in an automatic mode upon the entry of the lawn-mower into the lawn mower recovery-base.

6. Apparatus according to claim 4, wherein said respective connections are of inductive coupling type.

7. Apparatus according to claim 2, wherein said means for causing the lawn-mower to move in a preset direction comprise said control unit associated with wheels, said control unit being capable of giving command for the actuation of said wheels to move said lawn-mower in a direction allowing to keep its alignment with the perimeter.

8. Apparatus according to claim 3, wherein said control unit is capable of discriminating the upstream and downstream position of said sensors with respect to said lawn-mower.

9. Apparatus according to claim 8, wherein said control unit is configured to

detect that the first proximity sensor is in the proximity condition of the perimeter,

start said motor unit associated with wheels to make the latter to move said lawn-mower until a proximity condition of said second proximity sensor takes place as well and the alignment of said lawn-mower with said perimeter is obtained.

10. Apparatus according to claim 2, wherein said lawn mower further comprises a second proximity sensor, said control unit being configured to operate said motor unit for keeping both sensors in proximity of the perimeter.