Lawn mower robot

Patent metadata

Field	Value
Publication number	US-11096325-B2
Application number	US-201715856404-A
Country	US
Kind code	B2
Filing date	Dec 28, 2017
Priority date	Jan 2, 2017
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A lawn mower robot includes an inner body provided with casters and wheels for moving, a plurality of blades rotatably provided on a bottom surface of the inner body to cut grass, a drive motor mounted on the wheels, respectively, to independently drive the wheels, and an outer cover mounted on and configured to surround an outer side of the inner body to be movable in forward, backward, leftward and rightward directions with respect to the inner body when colliding with an obstacle. A plurality of ultrasonic sensors are provided to sense an obstacle, and an ultrasonic guide unit is formed to be recessed rearward from a front end portion of the outer cover so as to restrict a downward propagation angle of ultrasonic waves generated from the ultrasonic sensors.

First claim

What is claimed is:

1. A lawn mower robot, comprising:
an inner body provided with casters near a front side of the inner body and wheels near a rear side of the inner body;
a plurality of blades rotatably provided on a bottom surface of the inner body to cut grass;
a drive motor mounted on each of the wheels to independently drive the wheels;
an outer cover configured to surround the inner body and mounted on the inner body to be movable relative to the inner body, the outer cover being configured to move forward, backward, left and right with respect to the inner body when the outer cover of the lawn mover robot collides with an obstacle; and
support portions provided at front and rear upper portions of the inner body, to elastically support the outer cover,
wherein the support portions include:
a support portion body coupled to the outer cover and made of an elastic material to elastically support the outer cover; and
a plurality of curved portions coupled to an outer circumferential surface of the support portion body and curved along a radial direction from the support portion body to support the support portion body so as to be movable in lateral and vertical directions,
wherein the plurality of curved portions are aligned in the radial direction along an outer circumferential surface of the support portion body.

2. The lawn mower robot of claim 1 , further comprising:
a plurality of ultrasonic sensors provided at a front side of the outer cover to sense an obstacle in front of the lawn mower robot; and
an ultrasonic guide unit formed on the outer cover and configured to restrict a downward propagation angle of ultrasonic waves generated from the ultrasonic sensors.

3. The lawn mower robot of claim 2 , wherein the ultrasonic guide unit includes:
a lateral surface provided at a predetermined height above an upper end of a front end portion of the outer cover and extending from the front end of the outer cover toward a rear end of the outer cover;
a mounting surface provided a prescribed distance from the front end portion of the outer cover and extending upward from the lateral surface, wherein the plurality of ultrasonic sensors are embedded in the mounting surface; and
a side surface formed at both lateral sides of the mounting surface and angled laterally.

4. The lawn mower robot of claim 3 , wherein the lateral surface is angled relative to the ground such that a propagation angle of the ultrasonic waves in a vertical direction is greater than a prescribed minimum angle to restrict downward propagation of the ultrasonic waves.

5. The lawn mower robot of claim 3 , wherein the plurality of ultrasonic sensors are spaced apart from each other along the mounting surface.

6. The lawn mower robot of claim 2 , further comprising:
a control unit configured to control the drive motors according to a signal sensed from the plurality of ultrasonic sensors to reduce a driving speed of the wheels.

7. The lawn mower robot of claim 1 , further comprising:
a height adjusting lever rotatably mounted on the upper portion of the inner body to adjust a height of the blade;
a first opening formed at an upper portion of the outer cover in communication with the height adjusting lever; and
a first cover that is hinge-coupled to the outer cover to open and close the first opening.

8. The lawn mower robot of claim 7 , further comprising:
a display and a keypad provided at a rear upper portion of the inner body;
a second opening formed at a rear upper portion of the outer cover in communication with the display and the keypad; and
a second cover that is hinge-coupled to the outer cover to open and close the second opening.

9. The lawn mower robot of claim 8 , further comprising:
an emergency stop switch disposed between the first cover and the second cover, the emergency stop switch being mounted on the outer cover and configured to be pressed in an emergency to stop the wheels.

10. The lawn mower robot of claim 1 , further comprising:
a carry handle, both sides of which extend in an upwardly inclined manner from an upper front side of side surfaces of the outer cover to a rear side of the outer cover to protrude toward a rear upper portion of the outer cover, and having a rear end portion which is formed in a closed curved surface shape.

11. The lawn mower robot of claim 1 , further comprising charging terminals for charging a battery are provided at an upper portion of one side of the outer cover.

12. The lawn mower robot of claim 1 , further comprising IR receiving windows and IR sensors configured to sense a charging stand, the IR receiving windows being provided on front and rear surfaces of the outer cover, wherein the IR receiving window provided on the front surface of the outer cover is disposed at a position closer to the charging stand with respect to a longitudinal center line of the outer cover than the IR receiving window provided on the rear surface.

13. The lawn mower robot of claim 1 , further comprising:
a joystick bumper provided on the inner body to be rotatable in all directions, wherein an upper side of the joystick bumper is coupled to the outer cover and a sensing unit configured to sense collisions between the outer cover and an obstacle is provided at a lower side of the joystick bumper.

14. The lawn mower robot of claim 13 , wherein the joystick bumper includes:
a bumper body formed in a rod-shaped structure disposed to extend in a vertical direction;
a joint protrusion portion that protrudes from an intermediate portion of the bumper body and configured to allow movement of the upper side of the bumper body in lateral directions with respect to the inner body and mounted on a joint bumper mounting portion within the inner body; and
a spring having one side coupled to the joint bumper mounting portion within inner body and another side mounted on the bumper body to extend downward from the joint protrusion portion and configured to return the bumper body to an original position.

15. The lawn mower robot of claim 14 , wherein the sensing unit includes a magnet provided on a bottom end of the bumper body and a hall sensor provided within the inner body and configured to sense a collision between the outer cover and an obstacle by interaction with the magnet.

16. The lawn mower robot of claim 15 , wherein when the bumper body is in the original position, the magnet is positioned over the hall sensor, and when the bumper body is moved from the original position, the magnet is moved away from the hall sensor and the wheels are controlled to stop rotating.

17. The lawn mower robot of claim 13 , wherein the joystick bumper includes an elastic member having an upper end portion coupled to an upper portion of the joystick bumper to surround the joystick bumper, and a lower end portion coupled to the inner body to elastically support the joystick bumper, wherein the elastic member is formed in a bellows shape in which a width of the elastic member gradually decreases in an upward direction.

18. The lawn mower robot of claim 1 , further comprising:
a battery mounted within the inner body; and
a display and a keypad mounted on an upper rear side of the inner body.

19. A lawn mower robot, comprising:
an inner body;
an outer body to cover the inner body;
support portions provided at front and rear upper portions of the inner body to elastically support the outer body,
casters provided near a front side of the inner body;
wheels provided near a rear side of the inner body;
a plurality of bla

Assignees

• Lg Electronics Inc

Inventors

• Song Hyunsup
• Lee Changhyeon

Classifications

• A01D34/81 Primary

  Casings; Housings (A01D34/71 takes precedence) · CPC title

• A01D34/008 Primary

  for automated or remotely controlled operation · CPC title

• A01D34/412 Primary

  having rotating cutters · CPC title

• A01D2101/00

  Lawn-mowers · CPC title

• A01D34/78

  electric · CPC title