Robot cleaner and method for operating the same

• US 7,272,868 B2
• Filed: 05/04/2004
• Issued: 09/25/2007
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Jeon, Hyeong-Shin, Im, Hyoung-Bin
• Primary Examiner(s): Snider; Theresa T.
• Application Number:
  US10/837,660
• Publication Number:
  US 20050132522A1
• Time in Patent Office: 1,239 Days
• Field of Search: 153/19, 153/401, 153/403, 153/59, 153/62, 153/57, 153/58
• US Class Current: 15/319
• CPC Class Codes: A47L 2201/022 Recharging of batteries
• CPC Class Codes: A47L 2201/06 Control of the cleaning action for autonomous devices; Automatic detection of the surface condition before, during or after cleaning
• CPC Class Codes: A47L 9/009 Carrying-vehicles; Arrangements of trollies or wheels; Means for avoiding mechanical obstacles
• CPC Class Codes: A47L 9/2805 Parameters or conditions being sensed
• CPC Class Codes: A47L 9/2842 Suction motors or blowers
• CPC Class Codes: A47L 9/2852 Elements for displacement of the vacuum cleaner or the accessories therefor, e.g. wheels, casters or nozzles
• CPC Class Codes: A47L 9/2857 User input or output elements for control, e.g. buttons, switches or displays
• CPC Class Codes: A47L 9/2894 Details related to signal transmission in suction cleaners
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area

Abstract

A robot cleaner includes a suction device installed within a cleaner body, that sucks dirt on a floor; a driver that moves the cleaner body; a detector mounted at the cleaner body, that detects a height between a bottom of the cleaner body and the floor; and a controller that controls the suction device in response to signal from the detector to adjust a suction force of the suction device in accordance with the height between the bottom of the cleaner body and the floor.

Claims

1. A robot cleaner comprising:

a suction device installed within a cleaner body, the suction device sucking dirt on a floor;

a driver that moves the cleaner body;

a detector mounted at the cleaner body, the detector detecting a height between a bottom of the cleaner body and the floor; and

a controller that controls the suction device in response to signal a from the detector, the controller adjusting a suction force of the suction device in accordance with the height between the bottom of the cleaner body and the floor.

2. The robot cleaner of claim 1, wherein the detector comprises:

a wheel installed at a bottom of the cleaner body to be contacted with the floor, and displaced in a vertical direction according to unevenness of the floor; and

a sensor that senses the amount of vertical displacement of the wheel.

3. The robot cleaner of claim 2, wherein the sensor comprises:

a connecting link hingedly connected to a rotational shaft of the wheel and pivotally connected to a pivot shaft fixed at the cleaner body in order to be rotated centering on the pivot shaft by vertical displacement of the wheel;

a rotating plate installed at one end of the connecting link and having a plurality of slits formed in a direction that the connecting link is rotated; and

an optical sensor including a light emitter that emits light to the rotating plate and a light receiver that receives light passing through the slits of the rotating plate.

4. The robot cleaner of claim 3, wherein an elastic member is installed at the connecting link, of which one end is fixed to a casing of the cleaner body and provides an elastic force to the connecting link.

5. The robot cleaner of claim 1, wherein the detector is installed at a front in a direction that the cleaner body moves on the basis of a suction head of the suction device.

6. A robot cleaner comprising:

a suction device provided at a cleaner body, the suction device sucking dirt on a floor;

a driving wheel installed at the cleaner body and rotated by a driving motor to move the cleaner body;

at least one auxiliary wheel installed at a bottom of the cleaner body, supporting the cleaner body on a floor in a state of being in contact with the floor, and rotated by movement of the cleaner body; and

a detector that senses an amount of vertical displacement of the auxiliary wheel,

wherein the detector comprises;

a connecting link hingedly connected to a rotational shaft of the auxiliary wheel and pivotally connected to the cleaner body in order to be rotated according to unevenness of the floor; and

a sensor that senses the amount of rotation of the connecting link.

7. The robot cleaner of claim 6, wherein the sensing unit comprises:

a rotating plate installed at one end of the connecting link and having a plurality of slits; and

an optical sensor including a light emitter that emits light and a light receiver that receives light passing through the slits of the rotating plate.

8. The robot cleaner of claim 6, wherein the detector is installed at a front in a direction that the cleaner body travels on the basis of a suction head of the suction device.

9. The robot cleaner of claim 6, further comprising an elastic member that applies an elastic force to the auxiliary wheel.

10. An operating method of a robot cleaner comprising:

placing the robot cleaner on a floor;

carrying out cleaning operation by moving by itself and sucking dirt on the floor;

detecting a height between a bottom of the cleaner and the floor; and

controlling a suction force that sucks dirt on the floor in accordance with the height between the bottom of the cleaner and the floor.

11. The method of claim 10, wherein the detecting is performed by measuring a vertical displacement of a wheel that is installed at a bottom of the cleaner, rotated by movement of the cleaner, and displaced in a vertical direction according to unevenness of the floor.

12. The method of claim 10, wherein the controlling is performed by increasing a suction force when the height between the bottom of the cleaner and the floor is increased, and decreasing a suction force when the height between the bottom of the cleaner and the floor is decreased.