Lawn-mowing robot

Abstract

Provided is a lawn-mowing robot comprising: a body housing including a travel part at the lower portion thereof; and a driving assembly positioned inside the body housing, wherein the driving assembly includes: a bidirectional motor; a motor shaft which rotates by receiving the rotational force of the bidirectional motor; a blade shaft which is pin-slot-coupled with the motor shaft such that the rotation thereof is synchronized and the height thereof varies; a blade unit coupled to the lower end of the blade shaft; a lift cam including a shaft hole through which the blade shaft and the motor shaft pass; a one-way bearing positioned between the blade shaft and the lift cam; and a cam housing in which the lift cam is accommodated, wherein the lift cam rotates and the position thereof varies within the cam housing when the motor shaft rotates in a first direction, and the lift cam does not rotate and only the blade shaft rotates when the motor shaft rotates in a second direction.

Description

lawn mowing robot

[0001] The present invention relates to a lawn mowing robot and a control method thereof, and more particularly, to a lawn mowing robot capable of performing continuous work by automatically adjusting the height of a cutting blade.

[0002] A lawn mower robot is a device that moves autonomously and mows grass or lawns based on preset control information. Users can pre-enter control information related to the desired lawn mowing motion, time, and cycle. The lawn mower robot operates according to the input control information.

[0003] The environments where lawn mowing robots are used can be large areas, such as fields or gardens. Therefore, lawn mowing robots typically move along preset paths to mow grass and other grasses spread across large areas.

[0004] Additionally, the lawn mower robot divides the space into multiple smaller spaces and then moves along a preset path within each smaller space. This division allows the lawn mower robot to move densely within a large space. In other words, the lawn mower robot can pass through all spaces without missing any.

[0005] The above partition can be input through a control signal after the user sets up a virtual space. Alternatively, the partition can be performed by a physical method such as using a fence.

[0006] Lawn mowing robots can detect obstacles during their work and maneuver around them. However, for obstacles that protrude slightly above the ground, the cutting blade height needs to be adjusted to protect it. Furthermore, if the desired grass length varies depending on the area, the cutting blade height needs to be adjusted.

[0007] In the past, the cutting blade had to be adjusted manually, but for the full automation of the lawn mowing robot, the height of the cutting blade also needs to be adjusted automatically.

[0008] The purpose of the present invention is to provide a lawn mowing robot capable of performing continuous work by automatically adjusting the height of a cutting blade.

[0009] The present invention provides a lawn mowing robot comprising: a main body housing including a driving part at the lower portion; and a driving assembly located inside the main body housing, wherein the driving assembly comprises: a bidirectional motor; a motor shaft that rotates by receiving rotational force from the bidirectional motor; a blade shaft that is pin-slot coupled so that rotation is synchronized with the motor shaft and its height is variable; and a blade unit coupled to the lower end of the blade shaft; a lift cam including a shaft hole through which the blade shaft and the motor shaft pass; a one-way bearing located between the blade shaft and the lift cam; and a cam housing in which the lift cam is accommodated, wherein when the motor shaft rotates in a first direction, the lift cam rotates and its position is variable within the cam housing, and when the motor shaft rotates in a second direction, the lift cam does not rotate and only the blade shaft rotates.

[0010] A cam groove including an inclined section formed on the outer surface of the lift cam; and

[0011] It may include a cam protrusion protruding from the inner surface of the cam housing and inserted into the cam groove.

[0012] The above cam groove can extend along the periphery of the cam housing and form a continuous path.

[0013] The cam groove may include an upper straight section; a lower straight section located below the upper straight section; and a pair of inclined sections connecting the upper straight section and the lower straight section.

[0014] The above pair of inclined sections can intersect each other in an x-shape.

[0015] The blade shaft may include an upper shaft into which the motor shaft is inserted; and a guide slot extending vertically to the upper shaft, and may include a guide protrusion formed on the motor shaft and inserted into the guide slot.

[0016] The above-mentioned lift cam may include a cam housing in which the lift cam is housed; a motor housing located laterally of the cam housing and in which the bidirectional motor is housed; a first gear connected to the bidirectional motor and located on an upper surface of the motor housing; and a second gear that rotates by receiving rotational force from the first power transmission gear and is connected to the motor shaft at an upper portion of the cam housing.

[0017] A main body housing including a driving part at the lower portion; and a driving assembly located inside the main body housing, wherein the driving assembly includes a motor; a motor shaft that rotates by receiving rotational force from the motor; a cam housing through which the motor shaft passes; a lift cam located inside the cam housing and rotating when the motor shaft rotates in a first direction and having a height that is variable in a vertical direction; a blade unit whose height changes according to a change in the height of the lift cam; a cam groove including an inclined section formed on an outer surface of the lift cam and forming a continuous path along the circumference of the lift cam; and a cam protrusion that protrudes from an inner surface of the cam housing and is inserted into the cam groove.

[0018] The cam groove may include an upper straight section; a lower straight section located below the upper straight section; and a pair of inclined sections connecting the upper straight section and the lower straight section.

[0019] The above pair of inclined sections can intersect each other in an x-shape.

[0020] The motor is a bidirectional motor that rotates in the first direction and a second direction that is opposite to the first direction, and includes a blade shaft that extends upward from the blade unit and is pin-slot coupled with the motor shaft; and a one-way bearing positioned between the blade shaft and the lift cam, wherein when the motor shaft rotates in the first direction, the lift cam rotates and its position within the cam housing is variable, and when the motor shaft rotates in the second direction, the lift cam does not rotate and only the blade shaft can rotate.

[0021] A lawn mowing robot according to at least one embodiment of the present invention can automatically adjust its height and perform lawn mowing work unmanned.

[0022] In addition, the lawn mowing robot according to at least one embodiment of the present invention has the advantage of having a simple configuration of a height-adjusting drive unit, thereby reducing the weight and volume of the drive unit.

[0023] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0024] FIG. 1 is a perspective view showing the appearance of a lawn mowing robot according to an embodiment of the present invention.

[0025] FIG. 2 is a side view showing the appearance of one side of the lawn mowing robot of FIG. 1.

[0026] FIG. 3 is a perspective view illustrating one embodiment of a drive assembly of a lawn mowing robot of the present invention.

[0027] Fig. 4 is a cross-sectional view of the drive assembly of the lawn mowing robot of the present invention with the blade unit moved upward.

[0028] FIG. 5 is a cross-sectional view of the drive assembly of the lawn mowing robot of the present invention with the blade unit moved downward.

[0029] FIGS. 6 to 8 are perspective views illustrating the operation of a lift motor according to one embodiment of a drive assembly of a lawn mowing robot of the present invention.

[0030] FIG. 9 is a cross-sectional view illustrating a drive assembly according to another embodiment of the present invention.

[0031] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components will be given the same reference numbers and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably only for the convenience of writing the specification, and do not in themselves have distinct meanings or roles. In addition, when describing the embodiments disclosed in this specification, if it is determined that a specific description of a related known technology may obscure the gist of the embodiments disclosed in this specification, a detailed description thereof will be omitted. In addition, the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

[0032] Terms that include ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by these terms. These terms are used solely to distinguish one component from another.

[0033] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0034] Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0035] In this application, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but should be understood not to exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0036] FIG. 1 is a perspective view showing the exterior of a lawn mowing robot (100) according to an embodiment of the present invention, and FIG. 2 is a side view showing the exterior of one side of the lawn mowing robot (100) of FIG. 1.

[0037] A lawn mowing robot (100) refers to a robot equipped with a lawn mowing device used for the purpose of tidying up a garden by cutting grass to a certain height. The lawn mowing robot (100) of the present invention refers to an autonomous robot that moves and mows grass automatically, rather than being held and moved by a worker.

[0038] A lawn mowing robot (100) according to an embodiment of the present invention may include a body (110), a driving unit (120), and a sensor unit (130). The body (110) may include a body (110) housing that forms an exterior for mounting components therein. The body (110) housing may include a lightweight and highly durable material, and for example, a synthetic resin such as reinforced plastic may be used.

[0039] A driving unit (120) may be positioned at the bottom of the body (110) housing, and may include various sensor units (130) for guiding the driving direction of the driving unit (120). The front may be aligned based on the driving direction.

[0040] The driving unit (120) may include a main wheel (121) that is connected to a driving motor to receive power and a sub wheel (122) for stable driving. As shown in FIGS. 1 and 2, a plurality of main wheels (121) may be provided, and in the present embodiment, they may be provided on the left and right sides, respectively.

[0041] A pair of main wheels (121) are independently driven and can change the driving direction by adjusting the rotation speed. The sub-wheel (122) can be rotated toward the direction steered by the main wheel (121).

[0042] The outer surface of the body (110) housing may include a sensor unit (130). It may include a camera (131) that collects image information to recognize the driving direction and detect obstacles in the driving direction, and a distance sensor (132) that detects the distance to the obstacle. The distance sensor is mainly positioned at the front based on the driving direction, and may be positioned at the left, right, or rear. The sensor unit (130) may include a location sensor that detects the location using GPS or the like in addition to optical information.

[0043] In addition to the sensor that assists driving, the robot may further include a height sensor to detect the distance from the ground and mow the lawn to a uniform height. The height sensor may measure the height from the ground or the top of the lawn. Multiple heights can be collected simultaneously, and the height of the mowing blade can be adjusted based on the height information with the lowest value.

[0044] A control unit (not shown) for controlling the driving unit (120) based on the input value of the sensor unit (130) may be mounted inside the body (110). The autonomous driving lawn mowing robot (100) may include a wireless communication unit for wireless communication with an external server or a user's terminal.

[0045] The lawn mowing robot (100) can store information such as distance information, image information, and location information acquired while driving, and can synthesize this information to form a map of the driving space and store it in a database.

[0046] A driving assembly (140) may be included within the body (110) housing. The driving assembly (140) includes a blade unit (144) that mows grass, and can mow grass by rotating the blade unit (144) using the rotational force of the blade motor. The height of the blade unit (144) can be adjusted based on the height from the ground acquired by the sensor unit (130) described above, so that the grass can be mowed to a desired length.

[0047] A battery may be included inside the body (110) housing for wireless operation. The battery may be connected to the control unit, sensor unit (130), driving unit (120), and driving assembly (140) to supply power.

[0048] Below, the configuration of the drive assembly (140) of the lawn mowing robot (100) will be described in detail with reference to the drawings.

[0049] Fig. 3 is a perspective view illustrating one embodiment of a drive assembly (140) of a lawn mowing robot (100) of the present invention. Fig. 4 is a cross-sectional view of a drive assembly (140) of a lawn mowing robot (100) of the present invention.

[0050] The drive assembly (140) includes a bidirectional motor (143), a motor shaft (1437), a blade shaft (1447), a blade unit (144), a lift cam (146), and a cam housing (149) in which the lift cam (146) is accommodated.

[0051] The blade unit (144) includes a disc-shaped unit having multiple blades for cutting grass, and is located at the bottom of the cam housing (149). A blade shaft (1447), which serves as a rotation axis of the blade unit (144), protrudes upward from the blade unit (144). The blade shaft (1447) receives power to rotate the blade unit (144) and cut the grass.

[0052] The bidirectional motor (143) can control the rotation direction of the motor differently depending on a signal. The power transmission gears (1435, 1436) that transmit the power of the bidirectional motor (1433) to the motor shaft (1437) may include a first gear (1435) connected to the bidirectional motor (143) and a second gear (1436) connected to the motor shaft (1437). The power transmission gears (1435, 1436) of the present embodiment are located on the upper side of the motor and cam housing (149), but may also be arranged on the lower side of the cam housing (149) as in the embodiment illustrated in FIG. 9.

[0053] The blade shaft (1447) is connected to the motor shaft (1437) so that it rotates together with the motor shaft (1437). Depending on the rotation direction of the bidirectional motor (143), the motor shaft (1437) can rotate in the first direction and the second direction, and the blade shaft (1447) can also rotate in the same manner.

[0054] The blade shaft (1447) and the motor shaft (1437) of the present invention may be coupled in a pin-slot manner so that they are not integrally connected but only rotate in synchronization and the height can be changed.

[0055] A pin-slot joint is a method of overlapping two shaft members, which may be composed of a vertical slot (1448) formed on one shaft and a slot pin (1438) formed on the other shaft. The slot pin (1438) is inserted into the vertical slot (1448) and moves in the extension direction of the vertical slot (1448), and a pair of shaft members can rotate together and move in the vertical direction independently.

[0056] In this embodiment, a slot pin (1438) protruding from a motor shaft (1437) is inserted into a vertical slot (1448) formed in a blade shaft (1447) and can move vertically. The blade shaft (1447) may include an upper shaft into which a motor shaft (1437) is inserted, and a vertical slot extending vertically to the upper shaft may be included.

[0057] Fig. 5 is a cross-sectional view of the drive assembly (140) of the lawn mowing robot (100) of the present invention in a state where the blade unit (144) has moved downward. As illustrated in Fig. 5, the position of the blade unit (144) may change as the position of the motor shaft (1437) changes within the upper shaft of the blade shaft (1447).

[0058] Since the size of the drive assembly (140) increases and the number of parts increases when a separate motor is provided to rotate the lift cam (146), the present invention is characterized in that the height of the blade unit (144) can also be adjusted using a bidirectional motor (143).

[0059] The motor shaft (1437) can rotate in the first direction and the second direction, and when rotated in the second direction, the blade unit (144) can mow the grass, and when rotated in the first direction, the height of the blade unit (144) can be changed. To change the height of the blade unit (144), the present invention may include a cylindrical lift cam (146).

[0060] When the motor shaft (1437) rotates in the first direction, the lift cam (146) rotates, but when it rotates in the second direction, the lift cam (146) does not rotate and only the motor shaft (1437) and the blade unit (144) rotate. The lift cam (146) can be coupled to the blade shaft (1447) by a one-way bearing (1425).

[0061] A bearing is a device that has low friction balls or the like interposed between two parts so that when one part rotates, the other part does not rotate. While a typical bearing is configured so that the rotating part does not affect the fixed part regardless of the direction of rotation, the one-way bearing (1425) used in the present invention is characterized by the fact that the rotating part rotates independently of the fixed part or the fixed part also rotates depending on the direction of rotation.

[0062] When the motor shaft (1437) rotates in the first direction, the blade shaft (1447) also rotates in the first direction, and at this time, the lift cam (146) rotates in the first direction with the blade shaft (1447) to adjust the height of the blade unit (144) (height adjustment mode).

[0063] When the motor shaft (1437) rotates in the second direction, the lift cam (146) does not rotate, and only the blade shaft (1447) rotates in the second direction, so that the blade unit (144) can mow the grass (lawn mowing mode).

[0064] The lift cam (146) may be positioned inside the cam housing (149) as illustrated in FIG. 3 and may include a cam groove (1465) formed on the outer surface. The cam groove (1465) includes an inclined section (1465c), and the lift cam (146) may move up and down within the cam housing (149) when the lift cam (146) rotates through the inclined section (1465c). A cam protrusion (1495) protruding from the inner surface of the cam housing (149) is inserted into the cam groove (1465), and when the lift cam (146) rotates, the cam protrusion (1495) may change its position on the cam groove (1465).

[0065] FIGS. 6 to 8 are perspective views illustrating the operation of a lift cam (146) according to one embodiment of a drive assembly (140) of a lawn mower robot (100) of the present invention. FIG. 6 shows a state in which the blade unit (144) is positioned at the highest position, FIG. 8 shows a state in which the blade unit (144) is positioned at the lowest position, and FIG. 7 shows a state in the middle of transitioning from FIG. 6 to FIG. 8, in which the cam protrusion (1495) is positioned at an inclined section (1465c) of the cam groove (1465).

[0066] As illustrated in FIGS. 6 to 8, the cam groove (1465) may include a pair of straight sections (1465a) having different heights and an inclined section (1465c) connecting the pair of straight sections (1465a).

[0067] When the cam projection (1495) passes through the inclined section (1465c), the lift cam (146) may be moved and its height may vary within the cam housing (149). In order to stably support the lift cam (146) by providing only one cam projection (1495) on one side, the cam groove (1465) may include a straight section (1465a). In this embodiment, the straight section (1465a) includes only two sections, but may include three or more sections, in which case the height may be changed in multiple stages.

[0068] Since the lift cam (146) of the present invention can only rotate in the first direction, the height must be able to both rise and fall when rotating in the first direction. Accordingly, the cam groove (1465) of the present invention forms a continuous path.

[0069] Both ends of the straight section (1465a) are connected to an inclined section (1465c), and the inclined section (1465c) includes an ascending section and a descending section. The ascending section and the descending section may intersect in an X shape, as illustrated in Fig. 7. If there are three or more straight sections (1465a), the number of intersections may increase.

[0070] FIG. 9 is a cross-sectional view showing a drive assembly (140) according to another embodiment of the present invention, in which the power transmission gears (1435, 1436) and the motor shaft (1437) are positioned below the lift cam (146).

[0071] In this embodiment, the blade shaft (1447) is positioned on the inside of the motor shaft (1437), and the blade shaft (1447) and the lift cam (146) can be fastened to the top of the lift cam (146) with a one-way bearing (1425).

[0072] The pin-slot joint of the present embodiment may be composed of a vertical slot (1439) formed in the motor shaft (1437) and a slot pin (1449) formed in the blade shaft (1447). The bidirectional motor (143) of the above-described embodiment is positioned at an upper side of the cam housing (149), but the bidirectional motor (143) of the present embodiment may be positioned at a lower side and adjacent to the cam housing (149).

[0073] The lawn mowing robot (100) of the present invention can implement both lawn mowing mode and height adjustment mode with one motor, thereby reducing manufacturing costs.

[0074] As described above, the lawn mowing robot (100) according to at least one embodiment of the present invention can automatically adjust its height and perform lawn mowing work unmanned.

[0075] In addition, the lawn mowing robot (100) according to at least one embodiment of the present invention has the advantage of having a small weight and volume of the driving unit since the configuration of the driving unit for height adjustment is not complicated.

[0076] The above detailed description should not be construed as limiting in any respect and should be considered illustrative only. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present invention are intended to be included within the scope of the present invention.

[0077] With respect to various embodiments for implementing the present invention, duplicate descriptions are omitted as they have been described above in the previous table of contents, Best Mode for Carrying Out the Invention.

[0078] The present invention is applicable to lawn mowing robots in various fields, and thus its industrial applicability is recognized.

Claims

1. A main body housing including a driving part at the bottom; and including a drive assembly located inside the main body housing, The above drive assembly Bidirectional motor; A motor shaft that rotates by receiving the rotational power of the above two-way motor; A pin-slot coupled blade shaft that rotates synchronously with the above motor shaft and has variable height; A blade unit coupled to the lower end of the above blade shaft; A lift cam including a shaft hole through which the blade shaft and the motor shaft pass; a one way bearing located between the blade shaft and the lift cam; and including a cam housing in which the above lift cam is accommodated; When the motor shaft rotates in the first direction, the lift cam rotates and its position within the cam housing changes. A lawn mowing robot characterized in that when the motor shaft rotates in the second direction, the lift cam does not rotate and only the blade shaft rotates.

2. In paragraph 1, A cam groove including an inclined section formed on the outer surface of the lift cam; and A lawn mowing robot comprising a cam protrusion protruding from the inner surface of the cam housing and inserted into the cam groove.

3. In paragraph 2, A lawn mowing robot, characterized in that the cam groove extends along the circumference of the cam housing and forms a continuous path.

4. In paragraph 2, The above cam groove is an upper straight section; A lower straight section located below the upper straight section; and A lawn mowing robot characterized by including a pair of inclined sections connecting the upper straight section and the lower straight section.

5. In paragraph 4, A lawn mowing robot characterized in that the above pair of inclined sections intersect each other in an X shape.

6. In paragraph 1, The above blade shaft an upper shaft into which the motor shaft is inserted; and It includes a guide slot extending vertically to the upper shaft, A lawn mowing robot characterized by comprising a guide protrusion formed on the motor shaft and inserted into the guide slot.

7. In paragraph 1, A cam housing in which the above lift cam is housed; A motor housing located laterally of the cam housing and housing the bidirectional motor; A first gear connected to the bidirectional motor and positioned on the upper surface of the motor housing; and A lawn mowing robot characterized by including a second gear that rotates by receiving the rotational power of the first power transmission gear and is connected to the motor shaft at the upper portion of the cam housing.

8. A main body housing including a driving part at the bottom; and including a drive assembly located inside the main body housing, The above drive assembly motor; A motor shaft that rotates by receiving the rotational power of the above motor; Cam housing through which the above motor shaft passes A lift cam located within the cam housing and rotating when the motor shaft rotates in the first direction and having a height that is variable in the vertical direction; A blade unit whose height changes according to the change in height of the above lift cam; A cam groove including an inclined section formed on the outer surface of the lift cam and forming a continuous path along the circumference of the lift cam; and A lawn mowing robot comprising a cam protrusion protruding from the inner surface of the cam housing and inserted into the cam groove.

9. In paragraph 8, The above cam groove is an upper straight section; A lower straight section located below the upper straight section; and A lawn mowing robot characterized by including a pair of inclined sections connecting the upper straight section and the lower straight section.

10. In paragraph 9, A lawn mowing robot characterized in that the above pair of inclined sections intersect each other in an X shape.

11. In paragraph 8, The above motor is a bidirectional motor that rotates in the first direction and a second direction that is opposite to the first direction, A blade shaft extending upward from the blade unit and pin-slot-connected with the motor shaft; A one-way bearing is included between the blade shaft and the lift cam, When the motor shaft rotates in the first direction, the lift cam rotates and its position within the cam housing changes. A lawn mowing robot characterized in that when the motor shaft rotates in the second direction, the lift cam does not rotate and only the blade shaft rotates.

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