Patent Description:
A robot cleaner may include a motor, various sensors, and artificial intelligence (AI) technology to clean an area requiring cleaning while traveling autonomously.

The robot cleaner may be configured to suction dust using a vacuum, to sweep up dust, or to wipe a surface using a mop.

As related art related to a robot cleaner, <CIT> (hereinafter referred to as "related art <NUM>") discloses "a robot cleaner and a method for operating it. " The robot cleaner disclosed in related art <NUM> includes a main body, a driver, a first rotating member and a second rotating member. In addition, the robot cleaner disclosed in related art <NUM> includes a first cleaner and a second cleaner made of cloth, a mop, a nonwoven fabric, a brush, or the like. The first cleaner is coupled to a first fixing member of the first rotating member, and the second cleaner is coupled to a second fixing member of the second rotating member.

According to related art <NUM>, as the first cleaner and the second cleaner are rotated by the rotational motion of the first rotating member and the second rotating member, foreign matter stuck to the floor may be removed through friction with the floor surface, and when a frictional force with the floor surface is generated, the frictional force can be used as power for moving the robot cleaner. That is, related art <NUM> describes that the robot cleaner can move while cleaning the floor based on the first cleaner and the second cleaner being rotated.

However, related art <NUM> fails to consider or recognize the following issue.

According to related art <NUM>, at least one of the first cleaner or the second cleaner may be separated, respectively, from the first fixing member or the second fixing member. The robot cleaner may be inadvertently operated while at least one of the first cleaner or the second cleaner is separated from the robot cleaner. For example, a user may accidentally operate the robot cleaner without recognizing that the first cleaner or the second cleaner is separated from the robot cleaner, or the first cleaner or the second cleaner may unintendedly become separated from the robot cleaner by friction with the floor or due to jamming.

If the first fixing member or the second fixing member are rotated while directly rubbing against the floor, the first fixing member or the second fixing member may be damaged or may scratch the floor.

Meanwhile, the robot cleaner disclosed in related art <NUM> includes a liquid management unit for discharging liquid to the first cleaner and the second cleaner. However, related art <NUM> fails to consider or recognize an issue relating to consumption of the liquid stored in the liquid management unit.

For example, in the robot cleaner disclosed in related art <NUM>, the liquid stored in the liquid management unit decreases as a result of use. Here, the robot cleaner may become imbalanced as the center of gravity in the entire robot cleaner changes. As a result, the robot cleaner may not move or clean as intended.

In particular, since the robot cleaner disclosed in related art <NUM> moves or travels based on the frictional forces with the floor that are generated when the first cleaner and the second cleaner are rotated, changes in the center of gravity in the robot cleaner may cause changes in the frictional force and a contact points between the floor and the first cleaner or the second cleaner such that the robot cleaner may not move an intended direction or with an intended speed or force.

In related art <NUM>, the liquid management unit may be disposed at a center position such that a center of gravity of the liquid management unit corresponds to the center of gravity of the first type of robot cleaner, and the center of gravity of the robot cleaner does not change as liquid is used, but this design may cause many design constraints.

As further related art related to a robot cleaner, <CIT> (hereinafter referred to as 'related art <NUM>') discloses a cleaner that includes a mop module including a mop portion and a collection module.

The cleaner disclosed in related art <NUM> provides various advantages such as effective mopping and travelling, the mop part easily detachable from the cleaner and easier manipulation of the cleaner. However, improvement of the cleaner is required when taking account of the following problems.

The cleaner disclosed in related art <NUM> includes a mop portion and a rotating plate. The mop portion is detachable from a mop fixing portion of the rotating plate. In the cleaner disclosed in related art <NUM>, the cleaner may be operated while the mop portion is separated from the cleaner. In this case, the rotating plate or the floor may be damaged, as described in relation to related art <NUM>.

<CIT> discloses an autonomous floor cleaner. The floor cleaner comprises a brush chamber, a brushroll rotatably mounted in the brush chamber, a controller for controlling the operation of the autonomous floor cleaner, and a fluid delivery system. The floor cleaner comprises a supply tank for storing a supply of cleaning fluid, at least one fluid distributor in fluid communication with the supply tank and configured to deposit cleaning fluid onto a surface to be cleaned; and a fluid delivery pump configured to control a flow of the cleaning fluid to the at least one fluid distributor, wherein a pulse width modulation signal powering the pump, from the controller, is further configured to provide a set flowrate of deposited cleaning fluid.

<CIT> discloses a robot cleaner. The robot cleaner includes a cleaning module having a left spin-mop and a right spin-mop configured to contact a floor while rotating in a clockwise direction or in a counterclockwise direction when viewed from above. The robot cleaner also includes a controller that manages the cleaning module such that, when the robot cleaner travels in a zigzag pattern including a first travel, during which the robot cleaner travels straight in a first direction, and a second travel, during which the robot cleaner travels straight in a second direction, which is opposite the first direction, a movement trajectory of the left spin-mop or the right spin-mop during the second travel overlaps a movement trajectory of the left spin-mop and a movement trajectory of the right spin-mop during the first travel.

<CIT> discloses a cleaner. The cleaner performs an autonomous driving, includes: a cleaner body; a driving unit for moving the cleaner body; a camera for detecting 3D coordinate information; a memory for storing pattern information related to a charging station; and a controller for comparing the 3D coordinates information detected by the camera with the pattern information related to the charging station stored in the memory, and for determining whether the charging station is positioned near the cleaner body based on a result of the comparison.

As the cleaning operation in the cleaner disclosed in related art <NUM> is performed while each of the mop module and the collection module comes into contact with the floor, it is less likely that the state of the mop portion in contact with the floor will be changed in accordance with consumption of water. However, there is a need to consider providing a method of facilitating stable cleaning and operation of the cleaner even though a separate collection module is not provided.

An aspect of the present invention is to provide a cleaner equipped with a pair of mops that rotate in contact with the floor, capable of preventing the cleaner from being damaged or the floor from being damaged even when the cleaner is operated in a separated state in which the mops are separated from the cleaner.

Another aspect of the present invention is to provide a cleaner in which mops come into intensive contact with the floor when the mops are coupled to the cleaner, and parts coupled to the mops are spaced apart from the floor when the mops are separated from the cleaner.

Still another aspect of the present invention is to provide a cleaner equipped with a water container configured to supply liquid (water) to a pair of mops, capable of facilitating stable contact and friction between the mops and the floor when the entire center of gravity of the cleaner changes in accordance with consumption of the liquid, even when the water container is not disposed at the center of gravity of the cleaner.

Still another aspect of the present invention is to provide a cleaner capable of facilitating stable mopping even when a motor, a battery, and a water container are respectively disposed at different positions so as to form a relatively flat cleaner.

Still another aspect of the present invention is to provide a cleaner in which a traveling direction of the cleaner can be controlled by a pair of mops rotating in contact with the floor, and that includes an auxiliary means for controlling the traveling direction of the cleaner.

The problem is solved by the cleaner that is set out in the appended set of claims.

According to the present invention, the cleaner includes the first support wheel and the second support wheel and the auxiliary wheel, in which the lowest parts of the first rotating plate and the second rotating plate are higher than the virtual reference line connecting the lowest part of the support wheel to the lowest part of the auxiliary wheel, and the lowest parts of the first mop and the second mop are lower than the reference line. As a result, mopping may be performed by the first mop and the second mop when the first mop and the second mop are coupled to the first rotating plate and the second rotating plate, and the first rotating plate and the second rotating plate may be spaced apart from the floor when the first mop and the second mop are separated from the first rotating plate and the second rotating plate.

According to embodiments of the present invention, the cleaner may prevent the first rotating plate and the second rotating plate from rubbing against the floor even when the operation of the cleaner is performed when the first mop and the second mop are separated from the first rotating plate and the second rotating plate. Moreover, the present invention can provide an effect of effectively preventing the cleaner or the floor from being damaged as the support wheel and the auxiliary wheel move while rolling on the floor, even when the cleaner unintendedly moves on the floor.

According to embodiments of the present invention, the cleaner includes the first actuator disposed above the first rotating plate, the second actuator disposed above the second rotating plate, the battery disposed to lean toward the first support wheel and the second support wheel, and the water container disposed above the auxiliary wheel. Accordingly, upon initial operation of the cleaner, cleaning can be performed while only the first mop and the second mop contact the floor, and as the liquid is exhausted, cleaning can be performed while the first mop and the second mop and the first support wheel and the second support wheel contact the floor.

Thus, stable mopping can be performed even when the cleaner includes a water container which is not disposed at the center of gravity, and the height of the cleaner can be formed to be relatively low (flat).

Further, in the cleaner according to embodiments of the present invention, as the rotation axis of the first support wheel and the rotation axis of the second support wheel are parallel to the virtual connection line connecting the rotation axis of the first rotating plate to the rotation axis of the second rotating plate, the first support wheel and the second support wheel can assist in forward movement of the cleaner.

More specific effects and additional effects to be achieved by the cleaner according to the embodiment of the present invention will be described below with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to accompanying drawings, and the same or similar elements are designated with the same numeral references regardless of numerals in the drawings.

X, Y, and Z directions shown in the accompanying drawings are orthogonal to each other.

<FIG> is a diagram illustrating a perspective view of a cleaner <NUM> according to an embodiment of the present invention. <FIG> is a diagram illustrating the partial configuration separated from the cleaner <NUM> shown in <FIG>. <FIG> is a diagram illustrating a back view of the cleaner <NUM> shown in <FIG>. <FIG> is a diagram illustrating the partial configuration separated from the cleaner <NUM> shown in <FIG>.

The cleaner <NUM> according to embodiments of the present invention may be a robot cleaner <NUM>. The cleaner <NUM> according to an embodiment of the present invention may be placed on a floor surface B and may move along and clean the floor surface B. Accordingly, hereinafter, in order to describe the cleaner <NUM>, a vertical direction may be set based on a state in which the cleaner <NUM> is placed on the floor.

Further, in the following description, it is assumed that a side of the cleaner <NUM> where support wheels <NUM>, <NUM>, and <NUM> (to be described below) are coupled relative to a first rotating plate <NUM> and a second rotating plate <NUM> correspond to a "front" side of the cleaner <NUM>.

The 'lowest part' of a component described in embodiments of the present invention may be a part at which each component is located lowest or closest to the floor when the cleaner <NUM> is placed on the floor.

The cleaner <NUM> according to an embodiment of the present invention may include a body <NUM>, a first rotating plate <NUM>, a second rotating plate <NUM>, a first mop <NUM>, and a second mop <NUM>.

The body <NUM> may form an overall appearance of the cleaner <NUM> or may be formed as a frame. Each component constituting the cleaner <NUM> may be coupled to the body <NUM>, and some components constituting the cleaner <NUM> may be accommodated in the body <NUM>. The body <NUM> may be divided into a lower body 100a and an upper body 100b, and the components of the cleaner <NUM> may be provided in a space where the lower body 100a and the upper body 100b are coupled to each other (see <FIG>).

In an embodiment of the present invention, the body <NUM> may have a width (or diameter) larger in the horizontal direction (direction parallel to X and Y) than the height in the vertical direction (direction parallel to Z). Such a body <NUM> may provide an advantageous structure for helping the cleaner <NUM> to have a stable structure and to avoid obstacles when moving (traveling).

When viewed from above or below, the body <NUM> may be formed in various forms, such as a circle, an oval, or a rectangle.

The first rotating plate <NUM> may be formed to have a predetermined area and may be formed substantially in the form of a flat plate or a flat frame. The first rotating plate <NUM> may generally be positioned to extend substantially horizontally. As such, the first rotating plate <NUM> has a width (or diameter) in the horizontal direction set to be significantly larger than the height in the vertical direction. The first rotating plate <NUM> coupled to the body <NUM> may be parallel to the floor surface B, or may be inclined with respect to the floor surface B.

The first rotating plate <NUM> may be formed in a circular plate shape, and the bottom surface of the first rotating plate <NUM> may generally have a circular shape.

The first rotating plate <NUM> may be formed in a rotationally symmetrical form as a whole.

The first rotating plate <NUM> may include a first central plate <NUM>, a first outer plate <NUM>, and first spokes <NUM>.

The first central plate <NUM> may be rotatably coupled to the body <NUM> while forming the center of the first rotating plate <NUM>. The first central plate <NUM> may be coupled to the lower portion of the body <NUM>, and the upper surface of the first central plate <NUM> may be coupled to a lower surface of the body <NUM> while facing the lower surface of the body <NUM>.

A rotation axis <NUM> of the first rotating plate <NUM> may be formed along a direction passing through the center of the first central plate <NUM>. In addition, the rotation axis <NUM> of the first rotating plate <NUM> may be formed along a direction orthogonal to the floor surface B, or may have a predetermined inclination with respect to the direction perpendicular to the floor surface B.

The first outer plate <NUM> may be formed to surround the first central plate <NUM> while being spaced apart from the first central plate <NUM>.

The first spokes <NUM> may connect the first central plate <NUM> and the first outer plate <NUM>, and are provided in plural and are repeatedly formed along the circumferential direction of the first central plate <NUM>. The first spokes <NUM> may be arranged at equal intervals. A plurality of holes <NUM> penetrating vertically between the first spokes <NUM> may be provided, and a liquid (such as water) discharged from a water supply tube <NUM> to be described below may be transferred to the first mop <NUM> through the holes <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the bottom surface of the first rotating plate <NUM> coupled to the body <NUM> may form a predetermined incline with respect to the floor surface B. Herein, the rotation axis <NUM> of the first rotating plate <NUM> may have a predetermined incline with respect to a direction perpendicular to the floor surface B.

In the cleaner <NUM> according to an embodiment of the present invention, an angle θ1 formed between the bottom surface of the first rotating plate <NUM> and the floor surface B may be correspond to an angle θ2 formed between the rotation axis <NUM> of the first rotating plate <NUM> and the direction perpendicular to the floor surface B. Accordingly, when the first rotating plate <NUM> rotates with respect to the body <NUM>, the bottom surface of the first rotating plate <NUM> may be configured to maintain the same angle with the floor surface B.

The second rotating plate <NUM> may be formed to have a predetermined area and may be formed in the form of a flat plate or a flat frame. The second rotating plate <NUM> generally lies horizontally. As such, a width (or diameter) in the horizontal direction may be set to be significantly larger than the height in the vertical direction. The second rotating plate <NUM> coupled to the body <NUM> may be disposed parallel to the floor surface B, or may be inclined with respect to the floor surface B.

The second rotating plate <NUM> may be formed in a substantially circular plate shape, and the bottom surface of the second rotating plate <NUM> may generally have a circular shape.

The second rotating plate <NUM> may be formed in a rotationally symmetrical form as a whole.

The second rotating plate <NUM> may include a second central plate <NUM>, a second outer plate <NUM>, and second spokes <NUM>.

The second central plate <NUM> may be rotatably coupled to the body <NUM> while forming the center of the second rotating plate <NUM>. The second central plate <NUM> may be coupled to the lower portion of the body <NUM>, and the upper surface of the second central plate <NUM> may be coupled to a lower surface of the body <NUM> while facing the lower surface of the body <NUM>.

A rotation axis <NUM> of the second rotating plate <NUM> may be formed along a direction passing through the center of the second central plate <NUM>. In addition, the rotation axis <NUM> of the second rotating plate <NUM> may be formed along a direction orthogonal to the floor surface B, or may have a predetermined inclination with respect to the direction orthogonal to the floor surface B.

The second outer plate <NUM> is formed to surround the second central plate <NUM> while being spaced apart from the second central plate <NUM>.

The second spokes <NUM> connect the second central plate <NUM> and the second outer plate <NUM>, and are provided in plural and are repeatedly formed along the circumferential direction of the second central plate <NUM>. The second spokes <NUM> may be arranged at substantially equal intervals. A plurality of holes <NUM> penetrating vertically between the second spokes <NUM> may be provided, and the liquid (such as water) discharged from the water supply tube <NUM> to be described below may be transferred to the second mop <NUM> through the holes <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the bottom surface of the second rotating plate <NUM> coupled to the body <NUM> may form a predetermined incline with respect to the floor surface B. Herein, the rotation axis <NUM> of the second rotating plate <NUM> may have a predetermined incline with respect to a direction perpendicular to the floor surface B.

In the cleaner <NUM> according to an embodiment of the present invention, an angle θ3, which is formed between the bottom surface of the second rotating plate <NUM> and the floor surface B, may substantially correspond to angle θ4, which is formed between the rotation axis <NUM> of the second rotating plate <NUM> and the direction perpendicular to the floor surface B. Accordingly, when the second rotating plate <NUM> rotates with respect to the body <NUM>, the bottom surface of the second rotating plate <NUM> may be configured to maintain a same angle with the floor surface B.

In the cleaner <NUM> according to an embodiment of the present invention, the second rotating plate <NUM> may be formed to correspond to the first rotating plate <NUM>, or may be formed to be symmetrical to the first rotating plate <NUM>. The first rotating plate <NUM> may be located on the left side of the cleaner <NUM>, whereas the second rotating plate <NUM> may be located on the right side of the cleaner <NUM>. Here, the first rotating plate <NUM> and the second rotating plate <NUM> may be bilaterally symmetrical to each other with respect to a midline of the body <NUM> extending in a front-to-rear direction.

The first mop <NUM> may be formed so that a bottom surface thereof that faces the floor B has a predetermined area, and the first mop <NUM> has a flat shape. The first mop <NUM> may have a shape in which the width (or diameter) thereof in the horizontal direction is significantly larger than the height in the vertical direction. When the first mop <NUM> is coupled to the body <NUM> side, the bottom surface of the first mop <NUM> may be parallel to the floor surface B, or may be inclined with respect to the floor surface B.

The bottom surface of the first mop <NUM> may be generally circular.

The second mop <NUM> may be formed in a rotationally symmetrical form as a whole.

The second mop <NUM> may be made of various materials that can clean the floor while being in contact with the floor. To this end, the bottom surface of the first mop <NUM> may be made of a cloth made of a woven or knitted fabric, a nonwoven fabric, and/or a brush having a predetermined area.

In the cleaner <NUM> according to an embodiment of the present invention, the first mop <NUM> may be detachably attached to the bottom surface of the first rotating plate <NUM>, and may be coupled to the first rotating plate <NUM> to be rotated together with the first rotating plate <NUM>. The first mop <NUM> may be in close contact with the bottom surface of the first outer plate <NUM>, and may be in close contact with the bottom surface of the first central plate <NUM> and the first outer plate <NUM>.

The first mop <NUM> may be detachably attached to the second rotating plate <NUM> using various devices and methods. In one embodiment, at least a portion of the first mop <NUM> may be coupled to the first rotating plate <NUM> by being hooked to or inserted into the first rotating plate <NUM>. In another embodiment, a separate device, such as a clamp that couples the first mop <NUM> to the first rotating plate <NUM>, may be provided. In still another embodiment, one side of one pair of fastening devices that can be coupled to and separated from each other may be fixed to the first mop <NUM>, and the other side thereof may be fixed to the first rotating plate <NUM>. As a specific example of the fastening device, a pair of magnets that work with each other, a pair of strips of Velcro that are coupled to each other, or a pair of buttons (a female button and a male button) that are coupled to each other may be used.

When the first mop <NUM> is coupled to the first rotating plate <NUM>, the first mop <NUM> and the first rotating plate <NUM> may be coupled to overlap each other, and the first mop <NUM> may be coupled to the first rotating plate <NUM> such that the center of the first mop <NUM> coincides with the center (e.g., rotational axis <NUM>) of the first rotating plate <NUM>.

The second mop <NUM> may be formed so that a bottom surface thereof that faces the floor has a predetermined area, and the second mop <NUM> has a flat shape. The second mop <NUM> has a shape in which the width (or diameter) in the horizontal direction is significantly larger than the height in the vertical direction. When the second mop <NUM> is coupled to the body <NUM>, the bottom surface of the second mop <NUM> may be parallel to the floor surface B, or may be inclined with respect to the floor surface B.

The bottom surface of the second mop <NUM> may be generally circular.

The second mop <NUM> may be made of various materials that can clean the floor while being in contact with the floor. To this end, the bottom surface of the second mop <NUM> may be made of a cloth made of a woven or knitted fabric, a nonwoven fabric, and/or a brush having a predetermined area.

In the cleaner <NUM> according to an embodiment of the present invention, the second mop <NUM> may be detachably attached to the bottom surface of the second rotating plate <NUM>, and may be coupled to the second rotating plate <NUM> to be rotated together with the second rotating plate <NUM>. The second mop <NUM> may be in close contact with the bottom surface of the second outer plate <NUM>, and may be in close contact with the bottom surface of the second central plate <NUM> and the second outer plate <NUM>.

The second mop <NUM> may be detachably attached to the second rotating plate <NUM> using various devices and methods. In one embodiment, at least a portion of the second mop <NUM> may be coupled to the second rotating plate <NUM> by being hooked to or inserted into the second rotating plate <NUM>. In another embodiment, a separate device, such as a clamp, which couples the second mop <NUM> to the second rotating plate <NUM>, may be provided. In still another embodiment one side of one pair of fastening devices coupled to and separated from each other may be fixed to the second mop <NUM> and the other side thereof may be fixed to the second rotating plate <NUM>. As a specific example of the fastening device, a pair of magnets that work with each other, a pair of strips of Velcro that are coupled to each other, or a pair of buttons (a female button and a male button) that are coupled to each other may be used.

When the second mop <NUM> is coupled to the second rotating plate <NUM>, the second mop <NUM> and the second rotating plate <NUM> may be coupled to overlap each other, and the second mop <NUM> may be coupled to the second rotating plate <NUM> such that the center of the second mop <NUM> coincides with the center (e.g., rotational axis <NUM>) of the second rotating plate <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the first rotating plate <NUM> and the second rotating plate <NUM> may respectively be inclined with respect to the floor surface B such that the sides of the first rotating plate <NUM> and the second rotating plate <NUM> that are closer to each other are spaced further apart from the floor surface B than the sides of the first rotating plate <NUM> and the second rotating plate <NUM> that are farther from each other. That is, the first rotating plate <NUM> and the second rotating plate <NUM> may be formed such that the sides thereof that are farther from the center of the cleaner <NUM> are located closer to the floor than the sides thereof that are closer to the center of the cleaner <NUM> (see <FIG>).

Here, the rotation axis <NUM> of the first rotating plate <NUM> may be formed to be perpendicular to the bottom surface of the first rotating plate <NUM>, and the rotation axis <NUM> of the second rotating plate <NUM> may be formed to be perpendicular to the bottom surface of the second rotating plate <NUM>.

When the first mop <NUM> is coupled to the first rotating plate <NUM> and the second mop <NUM> is coupled to the second rotating plate <NUM>, the sides of the first mop <NUM> and the second mop <NUM> that are farther from each other may be in relatively stronger contact with the floor.

When the first rotating plate <NUM> rotates, frictional force is generated between the bottom surface of the first mop <NUM> and the floor surface B. Here, since the generation point and direction of the frictional force deviate from the rotation axis <NUM> of the first rotating plate <NUM>, the first rotating plate <NUM> moves against the floor surface B, and the cleaner <NUM> can thus move along the floor surface B.

Further, when the second rotating plate <NUM> rotates, frictional force is generated between the bottom surface of the second mop <NUM> and the floor surface B. Here, since the generation point and direction of the frictional force deviate from the rotation axis <NUM> of the second rotating plate <NUM>, the second rotating plate <NUM> moves against the floor surface B, and the cleaner <NUM> can thus move along the floor surface B.

When the first rotating plate <NUM> and the second rotating plate <NUM> rotate at the same speed in opposite directions, the cleaner <NUM> may move straight, forward or backward. For example, when viewed from above, the cleaner <NUM> may move forward when the first rotating plate <NUM> rotates counterclockwise and the second rotating plate <NUM> rotates clockwise.

When only one of the first rotating plate <NUM> and the second rotating plate <NUM> rotates, the cleaner <NUM> may change direction.

When the rotation speed of the first rotating plate <NUM> is different from the rotation speed of the second rotating plate or when the first rotating plate <NUM> and the second rotating plate <NUM> rotate in the same direction, the cleaner <NUM> can move while changing direction, and can move in a curved direction.

<FIG> is a diagram illustrating a bottom view of the cleaner <NUM> according to another embodiment that is not part of the claimed invention and <FIG> is a diagram illustrating a side view of the cleaner <NUM> shown in <FIG>.

The cleaner <NUM> according to another embodiment that is not part of the claimed invention may include at least one support wheel <NUM> and an auxiliary wheel <NUM>.

The support wheel <NUM> may be coupled to the lower portion of the body <NUM> while being spaced apart from the first rotating plate <NUM> and the second rotating plate <NUM>.

The support wheel <NUM> may be formed as a common wheel. The support wheel <NUM> has a rotation axis formed to be parallel to the floor surface B. The support wheel <NUM> may move while rolling in contact with the floor. As a result, the cleaner <NUM> may move along the floor surface B.

The support wheel <NUM> according to an embodiment of the present invention may contact the floor together with the first mop <NUM> and the second mop <NUM>.

Considering the entire size of the cleaner <NUM>, a width W1 of the support wheel <NUM> in the direction of the rotation axis may be formed to be relatively wide. More specifically, when the support wheel <NUM> is placed on the floor surface B (when the rotation axis of the support wheel <NUM> is parallel to the floor surface B), one support wheel <NUM> may be formed have a width W1 capable of supporting a part of the load of the cleaner <NUM> such that the cleaner <NUM> remains upright without falling sideways. For example, the support wheel <NUM> may be formed to have a shape such as a roller.

The auxiliary wheel <NUM> may be coupled to the lower portion of the body <NUM> while being spaced apart from the first rotating plate <NUM> and the second rotating plate <NUM>.

A connection line L1 is a virtual line connecting the center of the first rotating plate <NUM> to the center of the second rotating plate <NUM> along a horizontal direction (e.g., in a direction parallel to the floor surface B), and the auxiliary wheel <NUM> and the support wheel <NUM> may be positioned at opposite sides of the bottom surface of the body <NUM> with respect to the connection line L1.

The auxiliary wheel <NUM> according to an embodiment of the present invention may be formed as a common wheel. The auxiliary wheel <NUM> may have a rotation axis <NUM> formed parallel to the floor surface B. The auxiliary wheel <NUM> may move while rolling in contact with the floor. As a result, the cleaner <NUM> may move along the floor surface B.

However, the auxiliary wheel <NUM> according to an embodiment of the present invention may not come into contact with the floor surface B when the first mop <NUM> and the second mop <NUM> come into contact with the floor.

The cleaner <NUM> according to an embodiment of the present invention may be formed to move straight along the floor surface B. For example, the cleaner <NUM> may move straight in the forward direction (toward the X direction), or straight in the backward direction, such as to avoid an obstacle or a drop.

In the cleaner <NUM> according to an embodiment of the present invention, the lowest parts of the first rotating plate <NUM> and the second rotating plate <NUM> may be formed to be higher than a virtual reference line L2 connecting the lowest part of the support wheel <NUM> to the lowest part of the auxiliary wheel <NUM>, and the lowest parts of the first mop <NUM> and the second mop <NUM> may be formed to be lower than the reference line L2.

That is, in the cleaner <NUM> according to an embodiment of the present invention, the support wheel <NUM> and the auxiliary wheel <NUM> do not interfere with the contact of the first mop <NUM> and the second mop <NUM> with the floor when the first mop <NUM> is coupled to the first rotating plate <NUM> and the second mop <NUM> is coupled to the second rotating plate <NUM>.

As a result, the first mop <NUM> and the second mop <NUM> may come into contact with the floor, and mopping and cleaning can be performed by rotation of the first mop <NUM> and the second mop <NUM>. Here, the support wheel <NUM> and the auxiliary wheel <NUM> may be spaced apart from the floor when the first mop <NUM> and the second mop <NUM> contact the floor. Alternatively, the auxiliary wheel <NUM> may be spaced apart from the floor while the support wheel <NUM>, the first mop <NUM>, and the second mop <NUM> come into contact with the floor.

In an embodiment of the present invention, when the cleaner <NUM> is placed on the floor such that the first mop <NUM> and the second mop <NUM> are in contact with the floor, the height from the floor surface B to the lowest part of the support wheel <NUM> is formed to be lower than the height from the floor surface B to the lowest part of the auxiliary wheel <NUM>.

Further, when the first mop <NUM> and the second mop <NUM> are separated from the first rotating plate <NUM> and the second rotating plate <NUM>, the support wheel <NUM> and the auxiliary wheel <NUM> may contact the floor, and lower surfaces of the first rotating plate <NUM> and the second rotating plate <NUM> may be spaced apart from the floor.

When the first mop <NUM> and the second mop <NUM> are separated and the cleaner <NUM><NUM> is operated (e.g., rotation of the first rotating plate <NUM> and the second rotating plate <NUM> is performed unintendedly), the configuration of cleaner <NUM> helps to prevent the first rotating plate <NUM> and the second rotating plate <NUM> from coming into contact with the floor and rubbing against the floor. As a result, damage to the first rotating plate <NUM> and the second rotating plate <NUM> may be avoided, and damage to the floor may be avoided.

In addition, even when the cleaner <NUM> unintendedly moves on the floor in this state, as the support wheel <NUM> and the auxiliary wheel <NUM> can move while rolling on the floor, the present invention may provide an effect of preventing the floor from being scratched, and effectively avoiding damage being caused to the cleaner <NUM> or the floor.

<FIG> is a diagram illustrating a bottom view of the cleaner <NUM> according to still another embodiment of the present invention. <FIG> and <FIG> are diagrams illustrating a side view of the cleaner <NUM> shown in <FIG>. <FIG> and <FIG> are diagrams illustrating a side view of the cleaner <NUM> while excluding a partial configuration of the cleaner shown in <FIG>.

The cleaner <NUM> according to an embodiment of the present invention may include a first support wheel <NUM>, a second support wheel <NUM>, and an auxiliary wheel <NUM>.

The auxiliary wheel <NUM> may be formed as described above.

In an embodiment of the present invention, the first support wheel <NUM> and the second support wheel <NUM> are spaced apart from each other, and may be formed as common wheels. The first support wheel <NUM> and the second support wheel <NUM> may move while rolling in contact with the floor. As a result, the cleaner <NUM> may move along the floor surface B.

The first support wheel <NUM> may be coupled to the bottom surface of the body <NUM> at a position spaced apart from the first rotating plate <NUM> and the second rotating plate <NUM>, and the second support wheel <NUM> may also be coupled to the bottom surface of the body <NUM> at a position spaced apart from the first rotating plate <NUM> and the second rotating plate <NUM>.

The second support wheel <NUM> is disposed at the same side as the first support wheel <NUM> (e.g., at a front of the body <NUM>) with respect to the aforementioned connection line L1. Here, the auxiliary wheel <NUM> may be disposed at the opposite side to the first support wheel <NUM> with respect to the connection line L1. That is, the first support wheel <NUM> and the second support wheel <NUM> may be disposed in front of the connection line L1, and the auxiliary wheel <NUM> may be disposed behind the connection line L1.

Considering the entire size of the cleaner <NUM>, a space between the first support wheel <NUM> and the second support wheel <NUM> may be formed to be relatively wide. More specifically, when the first support wheel <NUM> and the second support wheel <NUM> are placed on the floor surface B (when the rotation axis <NUM> of the first support wheel <NUM> and the rotation axis <NUM> of the second support wheel <NUM> are substantially parallel to the floor surface B), the first support wheel <NUM> and the second support wheel <NUM> may be spaced apart and support at least a part of the load of the cleaner <NUM> such that the cleaner <NUM> remains upright without falling sideways.

The first support wheel <NUM> may be disposed in front of the first rotating plate <NUM>, and the second support wheel <NUM> may be disposed in front of the second rotating plate <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the first rotating plate <NUM> and the second rotating plate <NUM> may be (bilaterally) symmetrical to each other, and the first support wheel <NUM> and the second support wheel <NUM> may be (bilaterally) symmetrical to each other with respect to the midline of the body <NUM> that extends in the front-to-rear direction.

In the cleaner <NUM> according to an embodiment of the present invention, the lowest part of the first rotating plate <NUM> may be formed to be higher than a first virtual reference line L3 connecting the lowest part of the first support wheel <NUM> to the lowest part of the auxiliary wheel <NUM>, and the lowest part of the first mop <NUM> may be formed to be lower than the first reference line L3 (see <FIG>).

Also, the lowest part of the second rotating plate <NUM> may be formed to be higher than a second virtual reference line L4 connecting the lowest part of the second support wheel <NUM> to the lowest part of the auxiliary wheel <NUM>, and the lowest part of the second mop <NUM> may be formed to be lower than the second reference line L4 (see <FIG>).

That is, in the cleaner <NUM> according to an embodiment of the present invention, the first support wheel <NUM>, the second support wheel <NUM>, and the auxiliary wheel <NUM> do not interfere with the contact of the first mop <NUM> and the second mop <NUM> with the floor when the first mop <NUM> is coupled to the first rotating plate <NUM> and the second mop <NUM> is coupled to the second rotating plate <NUM>.

As a result, the first mop <NUM> and the second mop <NUM> may come into contact with the floor, and mopping and cleaning can be performed by rotation of the first mop <NUM> and the second mop <NUM>. Here, the first support wheel <NUM>, the second support wheel <NUM> and the auxiliary wheel <NUM> may be spaced apart from the floor. Alternatively, the auxiliary wheel <NUM> may be spaced apart from the floor while the first support wheel <NUM> and the second support wheel <NUM> come into contact with the floor while the first mop <NUM> and the second mop <NUM> contact the floor.

In an embodiment of the present invention, when the cleaner <NUM> is placed on the floor such that the first mop <NUM> and the second mop <NUM> are in contact with the floor, the heights from the floor surface B to the lowest part of the first support wheel <NUM> and from the floor surface B to the lowest part of the second support wheel <NUM> may be lower than the height from the floor surface B to the lowest part of the auxiliary wheel <NUM>.

Further, when the first mop <NUM> and the second mop <NUM> are separated from the first rotating plate <NUM> and the second rotating plate <NUM>, the first support wheel <NUM>, the second support wheel <NUM> and the auxiliary wheel <NUM> may contact the floor, and the first rotating plate <NUM> and the second rotating plate <NUM> may be spaced apart from the floor (see <FIG> and <FIG>).

In this state, even when the operation of the cleaner <NUM> (rotation of the first rotating plate <NUM> and the second rotating plate <NUM>) is performed unintendedly, the cleaner <NUM> is capable of preventing the first rotating plate <NUM> and the second rotating plate <NUM> from coming into contact with the floor and rubbing against the floor. As a result, damage to the first rotating plate <NUM> and the second rotating plate <NUM> may be avoided, and damage to the floor may be avoided.

In addition, even when the cleaner <NUM> unintendedly moves on the floor in this state, the first support wheel <NUM>, the second support wheel <NUM> and the auxiliary wheel <NUM> can easily roll on the floor, thereby preventing the floor from being scratched, and effectively avoiding damage to the cleaner <NUM> or the floor.

<FIG> is a diagram illustrating a bottom view of the cleaner <NUM> according to still another embodiment of the present invention, and <FIG> is a diagram illustrating an exploded perspective view of the cleaner <NUM> shown in <FIG>.

The cleaner <NUM> according to an embodiment of the present invention may include a first actuator <NUM>, a second actuator <NUM>, a battery <NUM>, a water container <NUM>, and a water supply tube <NUM>.

The first actuator <NUM> may be coupled to the body <NUM> to rotate the first rotating plate <NUM>.

The first actuator <NUM> may include a first case <NUM>, a first motor <NUM>, and one or more first gears <NUM>.

The first case <NUM> may support the components constituting the first actuator <NUM>, and may be fixedly coupled to the body <NUM>.

The first motor <NUM> may be formed as an electric motor.

A plurality of first gears <NUM> may be formed to rotate while being engaged with each other. The first gears <NUM> may connect the first motor <NUM> to the first rotating plate <NUM>, and may transmit rotational power of the first motor <NUM> to the first rotating plate <NUM>. As a result, the first rotating plate <NUM> may rotate upon rotation of the rotation axis of the first motor <NUM>.

The second actuator <NUM> may be coupled to the body <NUM> to rotate the second rotating plate <NUM>.

The second actuator <NUM> may include a second case <NUM>, a second motor <NUM>, and one or more second gears <NUM>.

The second case <NUM> may support the components constituting the second actuator <NUM>, and may be fixedly coupled to the body <NUM>.

The second motor <NUM> may be formed as an electric motor.

A plurality of second gears <NUM> may be formed to rotate while being engaged with each other. The second gears <NUM> may connect the second motor <NUM> to the second rotating plate <NUM>, and may transmit rotation power of the second motor <NUM> to the second rotating plate <NUM>. As a result, the second rotating plate <NUM> may be rotate upon rotation of the rotation axis of the second motor <NUM>.

Likewise, in the cleaner <NUM> according to an embodiment of the present invention, the first rotating plate <NUM> and the first mop <NUM> may rotate by the operation of the first actuator <NUM>, and the second rotating plate <NUM> and the second mop <NUM> may rotate by the operation of the second actuator <NUM>.

In an embodiment of the present invention, the first actuator <NUM> may have a center of gravity <NUM> located inside a vertical area formed by the first rotating plate <NUM>. That is, by disposing the first actuator <NUM> directly on the first rotating plate <NUM>, loss of power transmitted from the first actuator <NUM> to the first rotating plate <NUM> may be minimized, and by applying a relatively heavy load of the first actuator <NUM> to the first rotating plate <NUM>, the first mop <NUM> may mop the floor while sufficiently rubbing the floor.

Further, in an embodiment of the present invention, the second actuator <NUM> may have a center of gravity <NUM> located inside a vertical area formed by the second rotating plate <NUM>. That is, by disposing the second actuator <NUM> directly on the second rotating plate <NUM>, loss of power transmitted from the second actuator <NUM> to the second rotating plate <NUM> may be minimized, and by applying a relatively heavy load of the second actuator <NUM> to the second rotating plate <NUM>, the second mop <NUM> may mop the floor while sufficiently rubbing the floor.

The second actuator <NUM> may be formed to be (bilaterally) symmetrical to the first actuator <NUM> with respect to a front-to-rear midline of the body <NUM>.

The battery <NUM> may be coupled to the body <NUM>, and may supply power to other components of the cleaner <NUM>. The battery <NUM> may supply power to the first actuator <NUM> and the second actuator <NUM>, and particularly, the battery <NUM> may supply power to the first motor <NUM> and the second motor <NUM>.

In an embodiment of the present invention, the battery <NUM> may be charged by an external power source, and for this purpose, one side of the body <NUM> or the battery <NUM> itself may include a charging terminal for charging the battery <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the battery <NUM> may be located inside a rectangular vertical area A formed using a center of the first rotating plate <NUM> (e.g., rotational axis <NUM>), the center of the second rotating plate <NUM> (e.g., rotational axis <NUM>), the center of the first support wheel <NUM>, and the center of the second support wheel <NUM> as the respective vertices. That is, the battery <NUM> may be disposed in front of the connection line L1.

In the cleaner <NUM> according to an embodiment of the present invention, the battery <NUM> may be coupled to the body <NUM> such that the longitudinal direction thereof is parallel to the connection line L1.

The water container <NUM> may be formed as a container having an inner space such that a liquid such as water can be stored therein. The water container <NUM> may be fixedly coupled to the body <NUM>, or may be detachably attached to the body <NUM>.

In an embodiment of the present invention, the water container <NUM> may be located behind the connection line L1, and the water container <NUM> may be located above an auxiliary wheel <NUM>.

The water supply tube <NUM> may be formed as a tube or pipe, and may be connected to the water container <NUM> such that the liquid in the water container <NUM> flows through the inside of the water supply tube <NUM>. The water supply tube <NUM> may have an end portion disposed at the opposite side connected to the water container <NUM>. The end portion of the water supply tube <NUM> is disposed above the first rotating plate <NUM> and the second rotating plate <NUM> so that liquid in the water container <NUM> may be supplied to the first mop <NUM> and the second mop <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the water supply tube <NUM> may be formed as one pipe that is branched into two end outlets. One end portion of the branched pipe may be disposed above the first rotating plate <NUM>, and the other end portion of the branched pipe may be disposed above the second rotating plate <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, a separate pump may be disposed to move liquid through the water supply tube <NUM>.

The center of gravity of the cleaner <NUM> may be located inside a rectangular vertical area A formed using the center of the first rotating plate <NUM>, the center of the second rotating plate <NUM>, the center of the first support wheel <NUM>, and the center of the second support wheel <NUM> as the respective vertices.

In the cleaner <NUM> according to an embodiment of the present invention, each of the first actuator <NUM>, the second actuator <NUM>, the battery <NUM>, and the water container <NUM> may be relatively heavy in the cleaner <NUM>. Accordingly, the first actuator <NUM> and the second actuator <NUM> may be located on the connection line L1 or adjacent to the connection line L1, the battery <NUM> may be located in front of the connection line L1, and the water container <NUM> may be located behind the connection line L1, so that the overall center of gravity of the cleaner <NUM> may be located at the center of the cleaner <NUM>. Accordingly, the first mop <NUM> and the second mop <NUM> may be in stable contact with the floor.

In addition, since the first actuator <NUM>, the second actuator <NUM>, the battery <NUM> and the water container <NUM> are each located on different areas in the plan view, it is possible to form a relatively flat body <NUM> and cleaner <NUM>, and it is possible to form a cleaner <NUM> that is easily able to enter a space under a shelf or a table.

In addition, according to the cleaner <NUM> according to an embodiment of the present invention, when the cleaner <NUM>, in which liquid is sufficiently contained in the water container <NUM>, is initially operated, the weight in the cleaner can be distributed evenly such that cleaning is performed while only the first mop <NUM> and the second mop <NUM> contact the floor. Here, when the center of gravity of the cleaner <NUM> moves forward as the liquid inside the water container <NUM> is consumed, cleaning may be performed while the first mop <NUM> and the second mop <NUM> contact the floor together with the first support wheel <NUM> and the second support wheel <NUM>.

<FIG> is a cross-sectional diagram schematically illustrating the cleaner <NUM> and components thereof according to still another embodiment of the present invention.

The cleaner <NUM> according to an embodiment of the present invention may include a controller <NUM>, a bumper <NUM>, a first sensor <NUM>, and a second sensor <NUM>.

The controller <NUM> may be configured to control the operation of the first actuator <NUM> and the second actuator <NUM> based on predetermined information or real-time information. In order to control the controller <NUM>, the cleaner <NUM> may include a storage medium in which an application program is stored. The controller <NUM> may be configured to control the cleaner <NUM> by driving the application program according to information inputted to the cleaner <NUM> and information outputted from the cleaner.

The bumper <NUM> may be coupled to the body <NUM> along the edge thereof, and may be configured to move relative to the body <NUM>. For example, the bumper <NUM> may be coupled to the body <NUM> so as to reciprocate in a direction toward the center of the body <NUM>.

The bumper <NUM> may be coupled along a portion of the edge of the body <NUM>, or may be coupled along the entire edge of the body <NUM>.

The first sensor <NUM> is coupled to the body <NUM>, and may be configured to detect movement (e.g., a relative movement) of the bumper <NUM> with respect to the body <NUM>. The first sensor <NUM> may include, for example, a microswitch, a photo interrupter, or a tact switch.

The controller <NUM> may control the cleaner <NUM> to avoid an obstacle when the bumper <NUM> of the cleaner <NUM> comes into contact with the obstacle, and may control the operation of the first actuator <NUM> and/or the second actuator <NUM> based on information obtained by the first sensor <NUM>. For example, when the bumper <NUM> comes into contact with an obstacle while the cleaner <NUM> is traveling, the position where the bumper <NUM> contacts may be recognized by the first sensor <NUM>, and the controller <NUM> may control the operation of the first actuator <NUM> and/or the second actuator <NUM> such that the cleaner <NUM> moves away from the contact position.

The second sensor <NUM> may be coupled to the body <NUM>, and configured to detect a relative distance from the obstacle. The second sensor <NUM> may be a distance sensor.

The controller <NUM> may control the operation of the first actuator <NUM> and/or the second actuator <NUM> such that the cleaner <NUM> changes its traveling direction or moves away from an obstacle when the distance between the cleaner <NUM> and the obstacle is less than a predetermined value based on information obtained by the second sensor <NUM>.

<FIG> is a diagram illustrating the size of each component in the cleaner <NUM> shown in <FIG>.

As described above, the cleaner <NUM> according to an embodiment of the present invention may move according to the frictional force between the first mop <NUM> and the floor surface B, which is generated when the first rotating plate <NUM> rotates, and the frictional force between the second mop <NUM> and the floor surface B, which is generated when the second rotating plate <NUM> rotates.

In the cleaner <NUM> according to an embodiment of the present invention, the first support wheel <NUM> and the second support wheel <NUM> may be formed such that the movement (travelling) of the cleaner <NUM> is not interfered with by the friction with the floor and no increase in load is caused when the cleaner <NUM> moves (travels).

To this end, a width W2 of the first support wheel <NUM> and a width W3 of the second support wheel <NUM> may be significantly smaller than a diameter D1 of the first rotating plate <NUM> or a diameter D2 of the second rotating plate <NUM>.

Specifically, the width W2 of the first support wheel <NUM> and the width W3 of the second support wheel <NUM> may be smaller than <NUM>/<NUM> of the diameter D1 of the first rotating plate <NUM> or the diameter D2 of the second rotating plate <NUM>.

Further, each of the diameter D1 of the first rotating plate <NUM> and the diameter D2 of the second rotating plate <NUM> may be greater than <NUM>/<NUM> and smaller than <NUM>/<NUM> of a diameter D5 of the body <NUM>. Each of a diameter D3 of the first mop <NUM> and a diameter D4 of the second mop <NUM> may be larger than <NUM>/<NUM> and smaller than <NUM>/<NUM> of the diameter D5 of the body <NUM>.

As such, even when the cleaner <NUM> is driven while the first support wheel <NUM> and the second support wheel <NUM> are in contact with the floor together with the first mop <NUM> and the second mop <NUM>, the frictional force between the first support wheel <NUM> and the floor surface B and the frictional force between the second support wheel <NUM> and the floor surface B may be made to be significantly smaller than the frictional force between the first mop <NUM> and the floor surface B and the frictional force between the second mop <NUM> and the floor surface B, thereby not causing unnecessary power loss and not hindering the movement of the cleaner <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, a horizontal distance C1 between the center of the first support wheel <NUM> and the center of the second support wheel <NUM> may be formed to be identical to or similar to a horizontal distance C2 between the center of rotation of the first rotating plate <NUM> and the center of rotation of the second rotating plate <NUM> (see <FIG>).

When the horizontal distance between the center of the first support wheel <NUM> and the center of the second support wheel <NUM> is C1 and the distance between the center of rotation of the first rotating plate <NUM> and the center of rotation of the second rotation plate <NUM> is C2, C1 may be greater than <NUM>*C2 and smaller than <NUM>*C2.

As a result, the cleaner <NUM> according to an embodiment of the present invention may be stably supported at four points by the first support wheel <NUM>, the second support wheel <NUM>, the first mop <NUM>, and the second mop <NUM>.

In the cleaner <NUM> according to an embodiment of the present invention, the rotation axis <NUM> of the first support wheel <NUM> and the rotation axis <NUM> of the second support wheel <NUM> may be parallel to the connection line L1. That is, the rotation axis <NUM> of the first support wheel <NUM> and the rotation axis <NUM> of the second support wheel <NUM> may be fixed (fixed bilaterally) to the body <NUM>.

The first support wheel <NUM> and the second support wheel <NUM> may be in contact with the floor together with the first mop <NUM> and the second mop <NUM>. In order to move the cleaner <NUM> in a straight line, the first mop <NUM> and the second mop <NUM> may rotate at a substantially same speed in opposing directions to each other. Herein, the first support wheel <NUM> and the second support wheel <NUM> assists in moving the cleaner <NUM> in a straight line in the front and rear directions.

The cleaner <NUM> according to an embodiment of the present invention may include an auxiliary wheel body <NUM>. Here, the auxiliary wheel body <NUM> may be rotatably coupled to the lower portion of the body <NUM>, and the auxiliary wheel <NUM> may be rotatably coupled to the auxiliary wheel body <NUM>. That is, the auxiliary wheel <NUM> may be coupled to the body <NUM> via the auxiliary wheel body <NUM>.

The rotation axis <NUM> of the auxiliary wheel <NUM> may be formed to intersect a rotation axis <NUM> of the auxiliary wheel body <NUM>. The rotation axis <NUM> of the auxiliary wheel <NUM> may be perpendicular to the rotation axis <NUM> of the auxiliary wheel body <NUM>. For example, the rotation axis <NUM> of the auxiliary wheel body <NUM> may be directed in the vertical direction or be slightly inclined in the vertical direction, and the rotation axis <NUM> of the auxiliary <NUM> may be directed in the horizontal direction.

In the cleaner <NUM> according to an embodiment of the present invention, the auxiliary wheel <NUM> may come into contact with the floor surface B when the cleaner <NUM> is not practically being used for cleaning or movement (e.g., when the first mop <NUM> and the second mop <NUM> are separated from the cleaner <NUM>). When the cleaner <NUM> enters this state, the direction in which the auxiliary wheel <NUM> is directed by the auxiliary wheel body <NUM> may be freely changed, and the cleaner <NUM> may be easily moved.

Claim 1:
A cleaner comprising:
a body (<NUM>);
a first rotating plate (<NUM>) and a second rotating plate (<NUM>) rotatably coupled to the body (<NUM>);
a first mop (<NUM>) configured to be detachably attached to a bottom surface of the first rotating plate (<NUM>);
a second mop (<NUM>) configured to be detachably attached to a bottom surface of the second rotating plate (<NUM>);
a first support wheel (<NUM>) coupled to the body (<NUM>);
a second support wheel (<NUM>) coupled to the body (<NUM>) at the same side of the first support wheel (<NUM>) with respect to a horizontal connection line connecting a center of the first rotating plate (<NUM>) to a center of the second rotating plate (<NUM>); and
an auxiliary wheel (<NUM>) coupled to the body (<NUM>) at the other side of the first support wheel (<NUM>) with respect to the connection line,
wherein a lowest part of the first rotating plate (<NUM>) is positioned above a first reference line connecting a lowest part of the first support wheel (<NUM>) to a lowest part of the auxiliary wheel (<NUM>), and a lowest part of the first mop (<NUM>) is positioned below the first reference line,
a lowest part of the second rotating plate (<NUM>) is positioned above a second reference line connecting a lowest part of the second support wheel (<NUM>) to the lowest part of the auxiliary wheel (<NUM>), and a lowest part of the second mop (<NUM>) is positioned below the second reference line, and
wherein the first rotating plate (<NUM>) and the second rotating plate (<NUM>) are inclined with respect to the connection line such that interior sides of the first rotating plate (<NUM>) and the second rotating plate (<NUM>) that are closer to each other are spaced further from the floor surface than exterior sides of the first rotating plate (<NUM>) and the second rotating plate (<NUM>) that are relatively farther from each other,
wherein, when the first and second rotating plates (<NUM>, <NUM>) rotates, frictional force is generated between the bottom surface of the first and second mop (<NUM>, <NUM>) and the floor surface (B) to move the cleaner (<NUM>) along the floor surface (B).