CN108378786B

CN108378786B - Cleaning pad

Info

Publication number: CN108378786B
Application number: CN201810208366.6A
Authority: CN
Inventors: M.J.杜利; N.罗马诺夫; M.威廉斯; J.M.约翰逊
Original assignee: iRobot Corp
Current assignee: iRobot Corp
Priority date: 2013-11-12
Filing date: 2014-11-11
Publication date: 2024-05-10
Anticipated expiration: 2034-11-11
Also published as: EP3453300A1; JP6165317B2; JP2016520354A; CN108514386A; KR101880832B1; AU2018203583A1; JP2023052443A; JP6896926B2; EP3453300B1; JP2021164652A; AU2014348883B2; CN108378786A; JP2019048130A; WO2015073429A1; AU2018203583B2; JP2017080522A; EP2945521A1; EP2945521A4; CN105120726B; AU2016259361B2

Abstract

A pad, particularly suitable for surface cleaning. The pad includes an absorbent core having the ability to absorb and retain liquid material and a backing layer contacting and covering at least one side of the absorbent core. The backing layer has the ability to retain and wick the liquid absorbent material through the backing layer. Cleaning devices containing such pads and methods of using such pads are also described.

Description

Cleaning pad

The application is a divisional application of the application patent application with the application date of 2014, 11 months and 11 days, the application number of 201480009726.X and the application name of cleaning pad.

Cross Reference to Related Applications

The present application is continued in the section of U.S. application Ser. No. 14/077296 entitled "autonomous surface cleaning robot" filed on Ser. No. 61/902838 entitled "cleaning pad" filed on Ser. No. 11/12 of 2013, and priority of U.S. provisional patent application Ser. No. 62/059637 entitled "surface cleaning pad" filed on Ser. No. 61/902838 entitled "cleaning pad" filed on Ser. No. 10/3 of 2014. Each of the above applications is assigned an entity in common. In addition, the entire contents of each of the above-mentioned patent applications are incorporated herein by reference for all purposes.

Technical Field

The present invention relates to floor cleaning using cleaning pads.

Background

Tile floors and countertops often require cleaning, some of which entail scrubbing to remove the dryness of the soil. Various cleaning tools are available for cleaning hard surfaces. Most tools include a cleaning pad that is removably attached to the tool. The cleaning pad may be disposable or reusable. In some examples, the cleaning pad is designed to fit a particular tool or may be designed to reference more than one tool.

Traditionally, wet mops have been used to remove dirt and other dirty stains (e.g., dust, grease, food, sauce, coffee grounds) from floor surfaces. One typically wets the mop in a bucket of water and soap or a special floor cleaning liquid and wipes the floor with the mop. In some examples, one may need to perform a back and forth scrubbing action to clean an area of a particular soil. The person then wets the mop in the same bucket to clean the mop and continues to wipe the floor. In addition, one may need to kneel on the floor to wipe the floor, which can be cumbersome and laborious, especially when the floor covers a large area.

Floor mops are used to scrub floors without requiring a person to kneel all the time. Pads attached to the mop or autonomous robot can scrub and remove solids from the surface without requiring the user to bend down to clean the surface, thereby preventing injury to the user.

Disclosure of Invention

A surface cleaning pad is described comprising an absorbent core comprising fibrous material that absorbs and retains liquid material; a backing layer (also referred to herein as a "wrap layer") contacting and covering at least one side of the absorbent core, comprising a fibrous material held and cored by the backing layer of liquid absorbent material. In embodiments, the cleaning pad is disposable or washable, reusable.

Other embodiments include the following elements or features taken in combination or sub-combination to provide the advantage of absorbing and retaining liquid and suspended debris to a compact mobile robot weighing less than 2.25 kg. The pad created by the following elements or features taken in combination or sub-combination wicks moisture and debris into the absorbent core without expanding and raising the front edge of the lightweight robot, which would hinder the robot's movement pattern and cleaning efficacy, as a maximum downward force, such as 1 pound force, would no longer be applied to the pad: the pad described above wherein the pad absorbs about 20 milliliters of liquid material with a pressure of about 0.9 pounds on the pad in about 10 seconds; the pad described above wherein the absorbent core retains up to about 90% of the volume of liquid material absorbed; the pad described above wherein the liquid material is substantially uniformly distributed throughout the absorbent core; the pad described above wherein the core material absorbs up to about 7 to about 10 times its weight; the pad described above wherein the backing layer retains up to about 10% of the absorbed liquid material; the pad described above wherein the absorbent core comprises cellulosic fibers; the pad described above wherein the absorbent core comprises a mixture of cellulose and polymer fibers; the pad described above wherein the absorbent core comprises nonwoven cellulose pulp; the pad as described above, wherein the cellulose pulp is a bonded polymer; the pad described above, wherein the polymer comprises polyethylene and/or polypropylene; the pad described above, wherein the absorbent core further comprises a surface layer comprising an acrylic latex, for example, to eliminate fluff; the pad described above, wherein the pad does not substantially compress or expand when absorbing or retaining a liquid, such as when wet; the pad described above, wherein the pad comprises a backing layer attached to the pad and is particularly adapted to attach the pad to a cleaning device; the pad described above, wherein the backing layer comprises paperboard; the pad above wherein the paperboard backing layer is 0.1 to 0.05 inches thick (0.254 cm to 0.127 cm thick); the pad above wherein the cardboard backing layer is 0.028 inches thick (0.07 cm thick); the pad described above, wherein the pad is coated with a polymer; the pad described above wherein the polymeric coating is about 0.010 to about 0.040 inches thick (0.0254 cm to 0.1016 cm thick); the pad described above, wherein the polymer is any polymer or wax material, for example, that is sealable against penetration by a liquid such as water (e.g., such as polyvinyl alcohol or a polyamine); the pad described above wherein the cardboard is attached to the pad with an adhesive; the pad described above wherein the absorbent core comprises first, second and third airlaid layers, each airlaid layer having a top surface and a bottom surface, the bottom surface of the first airlaid layer being disposed on the top surface of the second airlaid layer, the bottom surface of the second airlaid layer being disposed on the top surface of the third airlaid layer; the pad described above wherein the backing layer wraps around and covers at least two sides of the absorbent core; the pad described above, wherein the backing layer comprises a hydroentangled layer; the pad described above wherein the backing layer comprises a spunlaced (hydroentangled spundbond) or spunlaced layer having grooves of reduced thickness therein on the floor-facing surface and having a basis weight of 35-40gsm (grams per square meter). When the pad 100 is wet, there is not enough interface between the bottom surface of the liquid lubricated pad and the floor surface. A fully wetted pad will rest on a layer of fluid while the pad moves over the floor surface, but as the wet pad slowly absorbs the fluid, an insufficiently wetted, insufficiently lubricated coating will drag on the floor surface. In embodiments, the spunbond or hydroentangled cover is made of hydrophilic fibers that minimize the surface area of the mat that is exposed to air between the mat and the floor surface. If the grooves or pinholes are not part of the coating, the wet pad will stick to the hydrophilic floor surface. The spunbond or hydroentangled (such as herringbone groove patterns or square grid groove patterns) that apply surface texture to the wrap layer breaks down the surface tension that would otherwise cause the wet pad to adhere to the wet floor surface.

In an embodiment of the pad, the backing layer comprises meltblown abrasive fibers adhered to the sides of the backing layer not in contact with the absorbent core; the pad described above wherein the meltblown fibers have a diameter of between about 0.1 microns and about 20 microns; the pad described above wherein the meltblown abrasive fibers cover from about 44% to about 75% of the surface of the backing layer; in embodiments of the pad, the meltblown abrasive fibers cover about 50% to about 60% of the surface of the backing layer. The meltblown layer provides the pad with the advantage of disrupting the surface tension that would otherwise cause the wet wrap to stick to the wet floor. By adding texture and topography to the floor facing surface of the mat, the meltblown layer prevents the mat from sticking to or encountering high drag forces. The meltblown layer also provides a surface texture to the mat for roughening dirt and debris to be adhered or dried to the floor surface and for loosening dirt and debris to be absorbed through the airlaid core of the mat. In embodiments of the pad, the meltblown abrasive fibers and the backing layer have a collective thickness of between about 0.5 millimeters and about 0.7 millimeters. In other words, the maximum overlap thickness from the thickness of the applied meltblown outer layer to the surface of the wrapper layer is 0.7 millimeters. In embodiments of the pad, the wrapping layer has a thickness of between about 0.5 millimeters and about 0.7 millimeters. In an embodiment, the wrap has a global strategic partner (WSP) 10.1 (05) nonwoven water absorption test specification value of about 600%; the pad as described above, wherein the pad increases in thickness by less than 30% after absorption of the liquid material. In embodiments, the pad further comprises one or more of a fragrance, a cleaning agent, a surfactant, a foaming agent, a polish, a chemical preservative, a debris retention agent (such as DRAKESOL), and/or an antibacterial agent. In embodiments, the pad has a thickness of between about 6.5 millimeters and about 8.5 millimeters. In embodiments, the pad has a width of between about 68 millimeters and about 80 millimeters and a length of between about 165 millimeters and about 212 millimeters. In an embodiment, the backing layer has a width of between about 163 millimeters and about 169 millimeters and a length of between about 205 millimeters and about 301 millimeters. In an embodiment, the absorbent core comprises a first air-laid layer bonded to a second air-laid layer and the second air-laid layer is bonded to a third air-laid layer.

Fluid wicks between the three layers and remains uniformly and vertically throughout the airlaid layer stack when a downward force is applied to the pad without leaking back onto the floor surface beneath the cleaning pad. In embodiments, the pad maintains 90% of the fluid applied to the floor surface and less than 1 pound of force, and the pad does not leak absorbed liquid back onto the floor surface. The surface tension of the top and bottom surfaces of each airlaid layer helps to retain absorbed fluid within the layers such that when the top layer is fully saturated, no fluid will leak through the bottom surface 11b of the top airlaid layer down to the middle airlaid layer, and when the middle airlaid layer is fully saturated, no fluid will leak through the bottom surface of the middle (or second) layer down to the bottom layer.

In embodiments, the pad absorbs 8-10 times its weight of fluid into the relatively rigid matrix of the airlaid layer (no deformation of any dimension when fully wetted), and fluid absorption is achieved by capillary wicking, rather than releasing suction by compression, because the robot to which the pad is attached applies a very light, low-variation cycle weight, rather than a heavy pushing down and retracting cycle. Each airlaid layer slows the penetration of the absorbed fluid to the next adjacent airlaid layer so that early periods of fluid application do not result in rapid ingestion of all fluid applied to the floor surface. The vertical stacking of the airlaid layers provides resistance to puddling at the bottom of the airlaid core comprising three airlaid layers. Each airlaid layer has its own tamper resistant bottom surface for always preventing the absorbed fluid from being tampered with below the bottom of the bottom surface of the bottom (or third) layer.

In an embodiment, the stiffness or density of the airlaid layer is non-uniform in the vertical direction such that the outer top and bottom surfaces are stiffer than the interior of each layer. In an embodiment, as a feature of the manufacturing process, the surface density of the airlaid layer is non-uniform such that the outer top and bottom surfaces are smoother and less absorbent than the interior of each layer. By varying the surface density of the outer surface of each airlaid layer, the airlaid layer retains the absorbent wicking fluid into each airlaid layer without leaking back through the bottom surface. By incorporating three such air-laid layers into the absorbent core of the pad, the pad thus has excellent fluid retention properties relative to a pad having a single core with a thickness equivalent to a three-layer stacked core. The three airlaid layers provide at least three times the amount of surface tension.

In the pad embodiment, the three airlaid layers are adhered to one another by an adhesive material. In some embodiments, the adhesive material is applied in at least two evenly spaced strips along the length of at least one side of the airlaid layer and covers no more than 10% of the surface area of the at least one side. In an embodiment of the pad, the adhesive material is sprayed over the length of at least one side of the airlaid layer and covers no more than 10% of the surface area of the at least one side. In an embodiment of the pad, at least one airlaid layer comprises a cellulose-based textile material. In some embodiments, at least one and preferably all three of the airlaid layers comprise wood pulp. In some embodiments, the one or more airlaid layers comprise a biocomponent polymer, cellulose, and latex, and the polymer is present in an amount up to about 15% by weight.

Also described is a method for constructing a cleaning pad comprising disposing a first airlaid layer on a second airlaid layer; disposing a second airlaid layer on the third airlaid layer; and wrapping a wrap around the first, second and third airlaid layers, the wrap comprising: a fiber composition; and a meltblown abrasive adhered to a fibrous composition on an outer surface positioned to interface with a floor surface under the cleaning pad, the fibrous composition being a hydroentangled or spunbond material.

Other embodiments of methods for constructing a cleaning pad include the following elements or features taken in combination or sub-combination to provide the advantages of scrubbing debris from a floor surface and absorbing and retaining liquid and suspended debris when the pad is attached to a compact mobile robot weighing less than 2.25 kg, without impeding the robot's back and forth hundred vein (birdsfoot) or vining scrubbing pattern and cleaning efficacy. The pad created by the following elements or features taken in combination or sub-combination wicks moisture and debris into the absorbent core without expanding and raising the front edge of the lightweight robot, which will prevent the robot from applying maximum downward force to the pad: the method further includes adhering and randomly disposing meltblown abrasive fibers on the wrapping layer; the method above, wherein the meltblown abrasive fibers have a diameter between about 8 microns and about 20 microns; the method further comprises disposing the meltblown abrasive and the wrapping layer to have a collective thickness of between about 0.5 millimeters and about 0.7 millimeters; the method further comprises disposing a meltblown abrasive on the wrapping layer to provide a coverage surface ratio between the meltblown abrasive and the wrapping layer of between about 44% and about 57%; the pad described above wherein the meltblown abrasive fibers cover about 50% to about 60% of the surface of the backing layer; the method further comprises adhering the first airlaid layer to the second airlaid layer and adhering the second airlaid layer to the third airlaid layer; the method as described above, wherein the airlaid layer is a cellulose-based textile material; the method above, wherein the first, second, and third airlaid layers, the hydroentangled layer, and the meltblown abrasive are configured to increase in thickness by less than 30% after fluid absorption; the method further comprises configuring the airlaid layer and the wrapping layer to have a combined width of between about 80 millimeters and about 68 millimeters and a combined length of between about 200 millimeters and about 212 millimeters; the method further comprises configuring the airlaid layer and the wrapping layer to have a combined width of between about 6.5 millimeters and about 8.5 millimeters; the method further comprises configuring the airlaid layer to have a combined airlaid width of between 69 millimeters and about 75 millimeters and a combined airlaid length of between about 165 millimeters and about 171 millimeters.

A surface cleaning apparatus is also described having the above cleaning pad attached thereto. Further embodiments include wherein the surface cleaning apparatus is a mop or an autonomous mobile robot; the surface cleaning apparatus described above wherein the pad is releasably connected to the surface cleaning apparatus by a backing layer connected to the pad; the surface cleaning apparatus described above wherein the backing layer comprises paperboard; and the surface cleaning apparatus described above wherein the surface cleaning apparatus further comprises a release mechanism to eject the releasably attached pad.

A method of cleaning a surface using the pad described above is also described, comprising applying a surface cleaning liquid to the surface to be cleaned and passing the surface cleaning pad over the surface. The pad absorbs about 20 milliliters of liquid material over the pad in about 10 seconds using a pressure of about 400 grams force. In some embodiments, the absorbent core retains up to about 90% of the volume of the liquid material that is absorbed. In some embodiments, the absorbed liquid material is distributed substantially uniformly throughout the core. In some embodiments, the core material absorbs up to about 7 to about 10 times its weight. In some embodiments, the backing layer retains up to about 10% of the absorbed liquid material.

A mobile robot is also described. In an embodiment, the robot includes: a robot body defining a forward driving direction; a driver supporting the robot body to maneuver the robot over a surface, a cleaning assembly disposed on the robot body. The cleaning assembly includes a pad holder configured to receive a cleaning pad having a central edge and a side edge, the pad holder including a release mechanism configured to eject the pad upon actuation of the release mechanism. The robot further includes a fluid applicator configured to apply fluid to the floor surface, wherein the controller circuit is in communication with the driver and the cleaning assembly, the controller circuit controlling the driver and the fluid applicator to simultaneously perform a cleaning procedure. The cleaning procedure includes applying a fluid to a floor surface area approximately equal to a footprint area of the robot, and returning the robot to the floor surface area in a motion pattern that individually moves the center and side edges of the cleaning pad through the floor surface area to wet the entire surface area of the cleaning pad with the applied fluid.

Other embodiments include the robot described above, wherein the cleaning procedure further comprises applying a fluid to the floor surface to wet the cleaning pad at an initial volumetric flow rate that is relatively higher when the cleaning pad is wetted than a subsequent volumetric flow rate. In one embodiment, the first volumetric flow rate is set by initially spraying about 1mL of fluid per 1.5 feet for a period of time, such as 1-3 minutes, and the second volumetric flow rate is set by spraying every 3 feet, where the volume of each sprayed fluid is less than 1 mL. The fluid applicator applies fluid to the floor surface area in front of the cleaning pad and in the forward drive direction of the mobile robot, and the fluid is applied to the floor surface area previously occupied by the cleaning pad. In an embodiment, the previously occupied floor surface area is stored on a map that has access to the controller circuitry. In an embodiment, the fluid is applied to the floor surface area, the robot has backed away from at least one distance of the robot footprint length immediately prior to application of the fluid, such that the fluid is applied only to the penetrable floor, rather than triggering a bump sensor (bump) switch or a wall of a proximity sensor on the robot, furniture piece, carpet, or other non-floor area. In an embodiment, performing the cleaning procedure further includes moving the cleaning pad in a pulsatile motion forward and backward along the center trajectory, forward and backward to the left along the trajectory and away from the starting point along the center trajectory, and forward and backward to the right along the trajectory and away from the starting point along the center trajectory. The robot driver includes left and right driving wheels provided on respective left and right portions of the robot body, and the center of gravity of the robot is located in front of the driving wheels, so that most of the total weight of the robot is positioned on the pad holder. Because the pad does not expand during fluid absorption, the weight of the robot remains positioned on the pad holder throughout the cleaning procedure. The total weight of the robot is distributed between the pad support and the drive wheel in a ratio of 3 to 1, and the total weight of the robot when not holding any fluid is between about 1 kg and about 1.5 kg pounds, and between about 1.5 kg and 4.5 kg when holding fluid. In an embodiment, the robot body and the pad holder both define a substantially rectangular footprint. In addition, in an embodiment, the robot further includes a vibration motor disposed on the top of the pad holder. In some embodiments, the robot further comprises a toggle button for actuating the pad holder release mechanism and ejecting the pad. The backing layer on the pad engages with the pad holder, which includes protruding protrusions positioned for alignment along the peripheral edge of the backing layer and engaging one or more shaped slot cuts of the backing layer. In some embodiments, the pad holder includes protruding protrusions positioned for aligning and engaging one or more shaped slot cuts of the backing layer at locations other than along the peripheral edge.

Also described is a mobile floor cleaning robot comprising: a robot body defining a forward driving direction; a driver supporting the robot body to maneuver the robot on a surface, the driver including left and right driving wheels disposed on respective left and right portions of the robot body. The robot includes a cleaning assembly disposed on the robot body, the cleaning assembly including a pad support disposed in front of the drive wheel and having a top and a bottom, the bottom having a bottom surface disposed within between about 0.5 cm and about 1.5 cm of the surface and configured to receive a cleaning pad. The bottom surface of the pad holder includes at least 40% of the surface area of the robot footprint and has one or more protruding protrusions extending therefrom for engagement with mating slots on the pad assembly. In an embodiment, the robot includes a orbital shaker having an orbital range of less than 1 centimeter disposed on top of the pad support. The pad holder is configured to allow more than 80% of the orbital range of the orbital shaker to be transferred from the top of the received cleaning pad to the bottom surface of the received cleaning pad. The one or more protrusions help align the pad to the pad holder and hold the pad securely in place during oscillation of the orbital oscillation while the robot moves in a back-and-forth scrubbing cleaning pattern. In an embodiment, the pad holder comprises a release mechanism configured to eject the pad from the bottom surface of the pad holder upon actuation of the release mechanism, such that a user does not have to touch a used soiled pad to dispose of it. The release mechanism is actuated while the robot is held above the waste container to eject the mat from the mat support into the waste container thereunder.

In some embodiments, the orbital range of the orbital shaker is less than 0.5 cm during at least a portion of the cleaning operation. Further, the robot drives forward and backward while oscillating the cleaning pad. In an embodiment, the robot moves the cleaning pad forward and backward along the center trajectory, forward and backward to the left along the trajectory and away from the starting point along the center trajectory, and forward and backward to the right along the trajectory and away from the starting point along the center trajectory. The cleaning pad has a top surface connected to a bottom surface of the pad holder, the top of the pad being substantially stationary relative to the oscillating pad holder. In an embodiment, the robotic cleaning assembly further comprises: a reservoir holding a volume of fluid; and a fluid applicator in fluid communication with the reservoir. The fluid applicator is configured to apply fluid in a forward driving direction in front of the pad support. The cleaning pad is configured to absorb about 90% of the volume of fluid held in the reservoir without leaking onto the floor surface beneath the pad while receiving a1 pound downward force. The pad also includes a backing layer on the cleaning pad for engagement with the pad support, one or more protruding protrusions on the bottom of the pad support positioned for alignment and engagement with the shaped slot cut of the backing layer. The one or more protrusions help align the pad to the pad holder and hold the pad securely in place during oscillation of the orbital oscillation while the robot moves in a back-and-forth scrubbing cleaning pattern. In an embodiment, the pad holder comprises a release mechanism configured to eject the pad from the bottom surface of the pad holder upon actuation of the release mechanism, such that a user does not have to touch a used soiled pad to dispose of it. The release mechanism is actuated while the robot is held above the waste container to eject the mat from the mat support into the waste container thereunder.

Also described is a method of operating a mobile floor cleaning robot comprising driving a first distance to a first position in a forward driving direction defined by the robot while moving a cleaning pad carried by the robot along a floor surface supporting the robot, the cleaning pad having a center edge and side edges; driving the cleaning pad in a reverse drive direction opposite the forward drive direction a second distance to a second position while moving the cleaning pad along the floor surface; from the second position, applying fluid to an area on the floor surface substantially equal to the footprint area of the robot in a forward drive direction in front of the cleaning pad but behind the first position; and returning the robot to the area in a motion pattern that moves the center and side edges of the cleaning pad individually through the area to wet the cleaning pad with the applied fluid.

Further embodiments include: the method further comprises driving in a left driving direction or a right driving direction while driving in alternating forward and reverse directions by the applied fluid after spraying the fluid on the floor surface; the method above, wherein the fluid on the floor surface comprises spraying the fluid at a plurality of locations relative to the forward drive direction; the method above, wherein the second distance is at least equal to a length of one footprint area of the robot; the method as described above, wherein the moving floor cleaning robot comprises: a robot body defining a forward driving direction and having a bottom; a drive system supporting the robot body and configured to maneuver the robot over a floor surface.

One aspect of the present disclosure provides a mobile robot having a robot body, a drive system, and a cleaning assembly. The cleaning assembly includes a pad holder, a fluid applicator, and a controller. The drive system supports the robot body to maneuver the robot over a floor surface. The cleaning assembly is disposed on the robot body and includes a pad holder, a fluid applicator, and a controller in communication with the drive system and the cleaning system. The pad holder is configured to receive a cleaning pad having a central edge and a side edge. The pad holder includes a release mechanism configured to eject the pad upon actuation of the release mechanism. The fluid applicator is configured to apply a fluid to a floor surface. The controller controls the drive system and the fluid applicator while executing the cleaning procedure. The cleaning procedure includes applying fluid to an area approximately equal to the footprint area of the robot and returning the robot to the area in a motion pattern that moves the center and side edges of the cleaning pad individually through the area to wet the cleaning pad with the applied fluid.

Implementations of the disclosure may include one or more of the following features. In some embodiments, the cleaning procedure further includes applying a fluid to the surface to wet the cleaning pad at an initial volumetric flow rate that is relatively higher when the cleaning pad is wetted than a subsequent volumetric flow rate. In one embodiment, the first volumetric flow rate is set by initially spraying about 1mL of fluid per 1.5 feet for a period of time, such as 1-3 minutes, and the second volumetric flow rate is set by spraying every 3 feet, where the volume of each sprayed fluid is less than 1 mL.

In some examples, the fluid applicator applies fluid to an area in front of the cleaning pad and in a direction of travel of the mobile robot. In some examples, the fluid is applied to an area previously occupied by the cleaning pad. In some examples, the area occupied by the cleaning pad is recorded on a stored map that can be accessed to the controller.

In some examples, the fluid applicator applies the fluid to an area of the robot that has backed off a distance of at least one robot footprint length immediately prior to applying the fluid. Performing the cleaning procedure also includes moving the cleaning pad in a one hundred pulse motion forward and backward along the center trajectory, forward and backward to the left along the trajectory and away from the starting point along the center trajectory, and forward and backward to the right along the trajectory and away from the starting point along the center trajectory.

In some embodiments, the drive system includes left and right drive wheels disposed on respective left and right portions of the robot body. The center of gravity of the robot is located in front of the drive wheel such that the majority of the total weight of the robot is positioned on the pad holder. The total weight of the robot 20 may be distributed between the pad support and the drive wheel in a ratio of 3 to 1. In some examples, the total weight of the robot is between about 2 pounds and about 5 pounds.

In some examples, the robot body and the pad holder both define a substantially rectangular footprint. Additionally or alternatively, the bottom surface of the pad holder may have a width of between about 60 millimeters and about 80 millimeters and a length of between about 180 millimeters and 215 millimeters.

In some embodiments, the robot includes a toggle button for actuating the pad holder release mechanism and ejecting the pad. In some embodiments, the pad includes a backing layer for engagement with the pad holder, and the pad holder includes a protruding protrusion positioned for alignment with and engagement with the shaped slot cut of the backing layer.

One aspect of the present disclosure provides a mobile floor cleaning robot having a robot body, a driver, a cleaning assembly, a pad holder, and a controller circuit. The robot body defines a forward driving direction. The driver supports the robot body to maneuver the robot over a floor surface. The cleaning assembly is disposed on the robot body and includes a pad holder, a reservoir, and a sprayer. The pad holder has a bottom surface configured to receive a cleaning pad and arranged to engage a floor surface, the bottom surface having one or more protruding protrusions extending therefrom.

The one or more protrusions help align the pad to the pad holder and hold the pad securely in place during oscillation of the orbital oscillation while the robot moves in a back-and-forth scrubbing cleaning pattern. In an embodiment, the pad holder comprises a release mechanism configured to eject the pad from the bottom surface of the pad holder upon actuation of the release mechanism, such that a user does not have to touch a used soiled pad to dispose of it. The release mechanism is actuated while the robot is held above the waste container to eject the mat from the mat support into the waste container thereunder.

The reservoir is configured to hold a volume of fluid and a sprayer in fluid communication with the reservoir is configured to spray the fluid in a forward driving direction in front of the pad support. The controller circuit communicates with the drive system and the cleaning system and performs a cleaning procedure. The controller circuit executes a cleaning procedure that allows the robot to drive a first distance to a first position in a forward drive direction and then drive a second distance to a second position in a reverse drive direction opposite the forward drive direction. The cleaning procedure allows the robot to spray fluid on the floor surface from the second position in a forward driving direction in front of the pad holder but behind the first position. In this way, the robot applies fluid only to the penetrable floor, rather than triggering a bump sensor (bump) switch or a wall of a proximity sensor on the robot, furniture piece, carpet or other non-floor area. After spraying the fluid onto the floor surface, the cleaning procedure allows the robot to drive in alternating forward and reverse drive directions while applying the cleaning pad along the floor surface.

Implementations of the disclosure may include one or more of the following features. In some embodiments, the driver includes left and right drive wheels disposed on respective left and right portions of the robot body. The center of gravity of the robot is located in front of the drive wheel such that the majority of the total weight of the robot is positioned on the pad holder. The total weight of the robot may be distributed between the pad support and the drive wheel in a ratio of 3 to 1. In some examples, the total weight of the robot is between about 2 pounds and about 5 pounds (about 1 to 2.25 kilograms). The driver may include a driving body (which has a front and a rear) and left and right motors provided on the driving body. The left and right drive wheels may be coupled to respective left and right motors. The drive system may further include an arm extending from a front portion of the drive body. The arm is pivotally connected to the robot body in front of the drive wheel to allow the drive wheel to move vertically relative to the floor surface. The rear portion of the drive body may define a slot sized to slidably receive a guide projection extending from the robot body.

The reservoir may hold a liquid volume of about 200 milliliters. Additionally or alternatively, the robot may include a vibration motor or orbital oscillator disposed on top of the pad support.

Another aspect of the present disclosure provides a mobile floor cleaning robot including a robot body, a driver, and a cleaning assembly. The robot body defines a forward driving direction. The drive system supports the robot body to maneuver the robot over a floor surface. The cleaning assembly is disposed on the robot body and includes a pad holder and a rail oscillator. The pad holder is disposed in front of the drive wheel and has a top and a bottom. The base has a bottom surface disposed within between about 0.5 cm and about 1.5 cm of the floor surface and receives a cleaning pad. The bottom surface of the pad holder includes at least 40% of the surface area of the robot footprint and has one or more protruding protrusions extending therefrom. The orbital oscillator is disposed on top of the pad holder and has an orbital range of less than 1 cm. The pad holder is configured to allow more than 80% of the orbital range of the orbital shaker to be transferred from the top of the held cleaning pad to the bottom surface of the held cleaning pad.

In some embodiments, the orbital range of the orbital shaker is less than 0.5 cm during at least a portion of the cleaning operation. Additionally or alternatively, the robot may drive the cleaning pad forward or backward while the cleaning pad is oscillating.

In some examples, the robot moves in a one hundred vein motion, forward and backward along the center trajectory, forward and backward to the left along the trajectory and away from the starting point along the center trajectory, and forward and backward to the right along the trajectory and away from the starting point along the center trajectory.

In some examples, the cleaning pad has a top surface connected to a bottom surface of the pad support, and the top of the pad is substantially stationary relative to the vibrating pad support.

In some examples, the pad support has a release mechanism configured to eject a pad from a bottom surface of the pad support upon actuation of the release mechanism. In some examples, the robot includes a toggle button for actuating the pad holder release mechanism and ejecting the pad. In some examples, the pad includes a backing layer for engagement with the pad holder, and the pad holder includes a protruding protrusion positioned for alignment with and engagement with the shaped slot cut of the backing layer.

In some examples, the total weight of the robot is distributed between the pad support and the drive wheel in a ratio of 3 to 1. The total weight of the robot may be between about 2 pounds and about 5 pounds (about 1 to 2.25 kilograms).

The cleaning assembly may further include at least one post disposed on top of the pad support that is sized for receipt by a corresponding aperture defined by the robot body. The at least one post may have a cross-sectional diameter that varies along its length dimension. Additionally or alternatively, the at least one post may comprise a vibration damping material.

In some embodiments, the cleaning assembly further comprises a reservoir holding a volume of fluid and a nebulizer in fluid communication with the reservoir. The sprayer is configured to spray fluid in a forward driving direction in front of the pad holder. The reservoir may hold a liquid volume of about 200 milliliters.

The driver may include a driving body (which has a front and a rear) and left and right motors provided on the driving body. The left and right drive wheels are coupled to respective left and right motors. The driver may further include an arm extending from a front of the driving body. The arm is pivotally connected to the robot body in front of the drive wheel to allow the drive wheel to move vertically relative to the floor surface. The rear portion of the drive body may define a slot sized to slidably receive a guide projection extending from the robot body. In one embodiment, the cleaning pad disposed on the bottom surface of the pad holder body absorbs about 90% of the volume of fluid held in the reservoir. The cleaning pad has a thickness of between about 6.5 millimeters and about 8.5 millimeters, a width of between about 68 millimeters and about 80 millimeters, and a length of between about 165 millimeters and about 212 millimeters.

In some examples, a method includes driving a first distance to a first position in a forward driving direction defined by a robot while moving a cleaning pad carried by the robot along a floor surface supporting the robot. The cleaning pad has a central region and side regions transverse to the central region. The method further includes driving the cleaning pad in a reverse drive direction opposite the forward drive direction a second distance to a second position while moving the cleaning pad along the floor surface. In this way, the robot applies fluid only to the penetrable floor, rather than triggering a bump sensor (bump) switch or a wall of a proximity sensor on the robot, furniture piece, carpet or other non-floor area. The method further includes applying fluid to an area on the floor surface that is approximately equal to a footprint area of the robot in front of the cleaning pad but behind the first location. The method further includes returning the robot to the area where the fluid is applied in a motion pattern that moves the central portion and the side portions of the cleaning pad individually through the area to wet the cleaning pad with the applied fluid.

In some examples, the method includes driving in a left driving direction or a right driving direction while driving in alternating forward and reverse directions after spraying the fluid on the floor surface. Applying the fluid to the floor surface may include spraying the fluid at a plurality of locations relative to the forward drive direction. In some examples, the second distance is at least equal to a length of a footprint area of the robot.

In another aspect of the present disclosure, a method of operating a mobile floor cleaning robot includes driving a first distance to a first position in a forward driving direction defined by the robot while applying a cleaning pad carried by the robot along a floor surface supporting the robot. The method includes driving the second distance to a second position in a reverse drive direction opposite the forward drive direction while applying the cleaning pad along the floor surface. The method further includes spraying fluid onto the floor surface in a forward driving direction in front of the cleaning pad but behind the first location. The method further includes driving in alternating forward and reverse driving directions while applying a cleaning pad along the floor surface after spraying the fluid onto the floor surface.

In some embodiments, the method includes spraying the fluid on the floor surface while driving in a reverse direction or already driving in an opposite driving direction a second distance. In an embodiment, the method comprises driving in a left driving direction or a right driving direction, while driving in alternating forward and reverse directions after spraying the fluid on the floor surface. Spraying the fluid on the floor surface may include spraying the fluid at a plurality of locations relative to the forward drive direction. In some embodiments, the second distance is greater than or equal to the first distance.

The mobile floor cleaning robot may include a robot body, a drive, a pad holder, a reservoir, and a sprayer. The robot body defines a forward driving direction and has a bottom. The drive system supports the robot body and maneuvers the robot over a floor surface. The pad holder is provided on the bottom of the robot body and holds the cleaning pad. The pad holder has a release mechanism configured to eject the pad upon actuation, the pad further comprising a backing layer for engagement with the pad holder. The pad holder has a bottom surface with a protruding protrusion extending therefrom, and the protrusion is sized, shaped, and positioned to align with and engage the slot cut of the backing layer.

The reservoir is held and retains a fluid (e.g., 200 ml) by the robot body. A sprayer, also housed by the robot body, is in fluid communication with the reservoir and sprays fluid in a forward driving direction in front of the cleaning pad. The cleaning pad disposed on the bottom of the pad holder body may absorb about 90% of the fluid contained in the reservoir. In some examples, the cleaning pad has a width of between about 68 millimeters and about 80 millimeters and a length of between about 200 millimeters and about 212 millimeters. The cleaning pad may have a thickness of between about 6.5 millimeters and about 8.5 millimeters. The details of one or more embodiments of the disclosure are set forth in the accompanying drawings and the description below.

In some embodiments, the fluid applicator is a sprayer that includes at least two nozzles, each distributing fluid evenly across the floor surface in two strips of applied fluid. The two nozzles are each configured to spray fluid at a different angle and distance than the other nozzle. In some embodiments, two nozzles are stacked vertically in a recess in the fluid applicator and are inclined to the horizontal and spaced apart from each other such that one nozzle sprays a relatively long length of fluid forward and downward to cover an area in front of the robot with a forward supply of applied fluid, while the other nozzle sprays a relatively short length of fluid forward and downward such that a rearward supply of applied fluid is on an area closer to the front of the robot than the area of applied fluid dispensed by the top nozzle.

In an embodiment, the nozzles distribute fluid in a pattern of zones that expands in size the width of the robot and at least one length of the robot. In some embodiments, the top and bottom nozzles apply fluid in two different spaced apart strips of applied fluid that do not extend the full width of the robot such that the pad passes over the outer edges of the strips of applied fluid with a scrubbing action that is sloped forward and backward as described herein. In an embodiment, the strip of applied fluid covers a combined length of the robot length and a width of 75-95% of the robot width. In embodiments, the fluid-applied strip may be generally rectangular or oval. In an embodiment, the nozzle completes each spray cycle by drawing a small volume of fluid in the nozzle opening such that no fluid leaks from the nozzle following each spray instance.

In some embodiments, the pad includes a cardboard backing layer that includes a top surface adhered to the pad. The cardboard backing layer protrudes beyond the longitudinal edges of the mat, the protruding longitudinal edges of the cardboard backing layer being attached to the mat holders of the robot. In one embodiment, the cardboard backing layer has a thickness of between 0.02 and 0.03 inches (0.05 cm to 0.762 cm thick), a width of between 68 and 72 mm and a length of between 90-94 mm. In one embodiment, the cardboard backing layer is 0.026 inches thick, 70 millimeters wide and 92 millimeters long. In one embodiment, the paperboard backing layer is coated on both sides with a water-repellent coating, such as a wax or a polymer or a combination of water-repellent materials, such as wax/polyvinyl alcohol, polyamine, and the paperboard backing layer does not disintegrate when wetted.

In an embodiment, the pad is a disposable pad. In other examples, the pad is a reusable superfine fiber cloth pad having the same absorbent characteristics as those described herein with respect to the examples. In the example with a washable, reusable microfiber cloth, the top surface of the cloth includes a fixed rigid backing layer shaped and positioned to image the paperboard backing layer described in connection with the embodiments. The rigid backing layer is made of a heat resistant, washable material that undergoes mechanical drying without melting or degrading the backing. The rigid backing layer has a certain size and has a cutout as described herein used interchangeably with the embodiments of the pad holder described with respect to the embodiments herein.

In other examples, the pad is a disposable dry cloth and includes a single layer of needle punched spunbond or hydroentangled material exposing fibers for hair entrapment. The dry pad includes a chemical treatment that adds a tacky character to the pad for holding dirt and debris. In one embodiment, the chemical treatment is a commercially available material such as that sold under the trade name DRAKESOL.

In some examples, the mat is secured to the autonomous robot by a mat holder connected to the robot. The pad release mechanism adjusts to an upward or pad securing position. The pad release mechanism includes a retainer or lip that holds the pad securely in place by grasping the protruding longitudinal edge of the cardboard backing layer secured to the top of the pad. In an example, the tip or end of the pad release mechanism includes a movable retention clip and an ejection protrusion that slides up through a slot or opening in the pad holder and is pushed through the slot into a downward position to release the secured pad by pushing down on the attached cardboard backing layer.

Other aspects, features, and advantages will be apparent from the description and drawings, and from the claims.

Drawings

FIG. 1A is an exploded view of an exemplary cleaning pad.

FIG. 1B is an exploded view of the wrapping layer of the exemplary cleaning pad of FIG. 1.

FIG. 1C is a cross-sectional view of an exemplary cleaning pad.

FIG. 1D is a cross-sectional view of an exemplary cleaning pad wherein the airlaid layer comprises superabsorbent polymer.

Fig. 2A is a schematic diagram of an exemplary arrangement of operations for a hydroentangling process.

Fig. 2B is a perspective view of a hydroentangling process for preparing a hydroentangling layer used in an exemplary cleaning pad.

FIG. 3 is a perspective view of an apparatus for preparing an abrasive meltblown layer for use in an exemplary cleaning pad.

Fig. 4 is a perspective view of an autonomous mobile robot cleaned by use of an exemplary cleaning pad.

Fig. 5 is a perspective view of a mop using an exemplary cleaning pad.

Fig. 6 is a bottom view of an exemplary cleaning pad.

Fig. 7 is a schematic diagram of an exemplary arrangement for the operation of constructing a cleaning pad.

Fig. 8A is a perspective view of an exemplary cleaning pad.

Fig. 8B is an exploded perspective view of the exemplary cleaning pad of fig. 8A.

Fig. 8C is a top view of an exemplary cleaning pad.

Fig. 8D is a bottom view of an exemplary connection mechanism for a pad as described herein.

Fig. 8E is a side view of an exemplary attachment mechanism for a pad as described herein in a secured position.

Fig. 8F is a top view of an exemplary connection bracket for a pad as described herein.

Fig. 8G is a cut-away side view of an exemplary connection mechanism for a pad as described herein in a released position.

Fig. 9A-9C are top views of an exemplary autonomous mobile robot with which a fluid-ejecting floor surface is employed.

Fig. 9D is a top view of an exemplary autonomous mobile robot scrubbing a floor surface therewith.

Fig. 9E is a bottom view of an exemplary cleaning pad.

Fig. 9F is a top view of an exemplary autonomous mobile robot scrubbing a floor surface therewith.

Fig. 9G is a top view of an exemplary autonomous mobile robot scrubbing a floor surface therewith.

Fig. 10 is a schematic diagram of a robot controller of the exemplary autonomous mobile robot of fig. 4.

Like reference symbols in the various drawings indicate like elements.

Detailed Description

Referring to fig. 1A, 1B, and 1C, in some embodiments, the disposable cleaning pad 100 includes a plurality of absorbent airlaid layers 101, 102, 103, which are optionally bonded to one another, and are encased by an outer nonwoven layer 105 upon which abrasive meltblown elements 106 may be disposed. In some examples, the cleaning pad 100 includes one or more airlaid/dust free (airlaid) layers 101, 102, 103. As shown, the cleaning pad 100 includes first, second and third airlaid/dust free layers 101, 102, 103, although additional airlaid layers are also possible. The number of airlaid layers 101, 102, 103 can depend on the amount of cleaning liquid 172 that the cleaning pad 100 needs to absorb. Each airlaid layer 101, 102, 103 has a top surface 101a, 102a, 103a and a bottom surface 101b, 102b, 103b. The bottom surface 101b of the first (or top) airlaid layer 101 is disposed on the top surface 102a of the second airlaid layer 102, and the bottom surface 102b of the second airlaid layer 102 is disposed on the top surface 103a of the third (or bottom) airlaid layer 103. Fluid wicks between these three layers and remains uniformly and vertically throughout the airlaid layer stack when a downward force is applied to the pad 100 without leaking back onto the floor surface beneath the cleaning pad 100. In an embodiment, the pad 100 maintains 90% of the fluid applied to the floor surface 10 and less than 1 pound of force, and the pad 100 does not leak absorbed liquid back onto the floor surface 10. The surface tension of the top and bottom surfaces of each airlaid layer helps to keep absorbed fluid within the layers such that when the top layer 101 is fully saturated, no fluid will leak through the bottom surface 101b of the top airlaid layer 101 down to the middle airlaid layer 102, and when the middle airlaid layer 102 is fully saturated, no fluid will leak through the bottom surface 102b of the middle (or second) layer 102 down to the bottom layer.

In an embodiment, the pad 100 absorbs 8-10 times its weight into the relatively rigid matrix of the airlaid layers 101, 102, 103, and fluid absorption is achieved by capillary wicking, rather than releasing suction by compression, because the robot 400 to which the pad is attached applies a very light, low variation cycle weight, rather than a heavy pushing down and retracting cycle. Each airlaid layer 101, 102, 103 slows down the penetration of the absorbed fluid to the next adjacent airlaid layer 101, 102, 103 so that early periods of fluid application do not result in rapid absorption of all fluid applied to the floor surface. The vertical stacking of the airlaid layers 101, 102, 103 provides resistance to puddling at the bottom of the airlaid core comprising three airlaid layers 101, 102, 103. Each airlaid layer 101, 102, 103 has its own tamper resistant bottom surface 101b, 102b, 103b for always preventing absorbed fluid from being tamper under the bottom of the bottom surface 103b of the bottom (or third) layer 103 b.

In an embodiment, the stiffness or density of the airlaid layers 101, 102, 103 in the vertical direction is non-uniform such that the outer top and bottom surfaces are stiffer than the interior of each layer. In an embodiment, the surface density of the airlaid layers 101, 102, 103 is non-uniform such that the outer top and bottom surfaces are smoother and less absorbent than the interior of each layer. By varying the surface density of the outer surface 101b, 102b, 103b of each airlaid layer 101, 102, 103, the airlaid layers 101, 102, 103 retain absorbent wicking fluid into each airlaid layer without leaking back through the bottom surface 101b, 102b, 103 b. By incorporating three such air-laid layers 101, 102, 103 into the absorbent core of the pad 100, the pad 100 thus has excellent fluid retention properties relative to a pad having a single core corresponding to the thickness of a three-layer stacked core. The three air-laid layers 101, 102, 103 provide at least three times the amount of surface tension for retaining the absorbed fluid in the absorbent core of each air-laid layer 101, 102, 103.

The wrap layer 104 wraps around the airlaid layers 101, 102, 103 and prevents the airlaid layers 101, 102, 103 from being exposed. The wrap 104 includes a wrap 105 (e.g., a hydroentangled (spanlace) layer) and an abrasive layer 106. The wrap layer 105 wraps around the first, second and third airlaid layers 101, 102, 103. The wrapping layer 105 has a top surface 105a and a bottom surface 105b. The top surface 105b of the wrapping layer 105 covers the airlaid layers 101, 102, 103. The wrapping layer 105 may be a flexible material having natural or synthetic fibers (e.g., hydroentangled or spun-bonded). An abrasive layer 106 is provided on the bottom side 105b of the wrapping layer 105. Fluid applied to the floor 10 beneath the cleaning pad 100 is transported through the wrap layer 105 and into the airlaid layers 101, 102, 103. The wrapping layer 105, which wraps around the airlaid layers 101, 102, 103, is a transport layer that prevents the original absorbent material from being exposed to the airlaid layers. If the wrap 105 is too absorbent, the pad 100 will be sucked onto the floor 10 and will be difficult to remove. For example, the robot may not be able to overcome the suction force when attempting to move the cleaning pad 100 across the floor surface 10. In addition, the wrap 105 picks up dirt and debris loosened by the wear outer layer 106 and may leave a thin glossy cleaning fluid 172 on the air dried surface 10 without leaving streak marks on the floor 10. The thin gloss cleaning solution is between 1.5 and 3.5 ml/square meter and the duration of drying is no more than three minutes and preferably between about 2 minutes and 3 minutes.

The disposable cleaning pad 100 relies on capillary action (also referred to as wicking) to absorb liquid on the floor surface 10. Capillary action occurs when a liquid can flow in a narrow space without external forces such as gravity. Capillary action allows fluid movement within the space of the porous material due to adhesive forces, cohesive forces, and surface tension. Adhesion of the fluid to the walls of the container can cause upward forces on the edges of the liquid and result in a meniscus that tends to be upward. The surface tension is used to keep the surface intact. Capillary action occurs when the adhesion to the wall is stronger than the cohesion between fluid molecules.

In some examples, the airlaid layers 101, 102, 103 are textile-like materials made of fluff pulp (which is a type of wood pulp/chemical pulp made of long fiber cork). Chemical pulp is created by decomposing lignin (organic matter binding cells in wood pieces) by applying heat to a combination of wood chips and chemical materials in a large vessel. The textile-like material made from fluff pulp can be very bulky, porous, soft and have good water-absorbing properties. The fabric-like material does not scratch the floor surface, retains its strength even when it is wet, and can be washed and reused.

Referring to fig. 1D, in some embodiments, the airlaid layers 101, 102, 103 comprise an absorbent layer for a mixture of wet airlaid paper and superabsorbent polymer 108 (e.g., sodium polyacrylate). Polymers include plastics and rubber materials, which are primarily organic compounds chemically based on carbon, hydrogen and other nonmetallic elements. Polymers typically have a large molecular structure, which typically has a low density and can be very flexible. The superabsorbent polymer 108 (also known as slush molded powder) absorbs and retains a large amount of fluid compared to its own mass. The ability of the superabsorbent polymer 108 to absorb water depends on the ion concentration of the aqueous solution. Superabsorbent polymer 108 can absorb up to 500 times its weight of deionized distilled water (30-60 times its volume) and can be 99.9% liquid. The absorbency of the superabsorbent polymer 108 is significantly reduced to about 50 times its weight when placed in a 0.9% salt solution. The valency cations in the salt solution prevent the superabsorbent polymer 108 from binding with water molecules. The superabsorbent polymer 108 can expand, causing the cleaning pad 100 to expand as well. The various tools 400, 500 may use the cleaning pad 100, and in some examples, the tools 400, 500 may not support the inflatable cleaning pad 100. For example, expansion of the pad 100 may disrupt the physical properties of the compact lightweight robot 400, causing the compact robot 400 to tilt upward and apply less force to the pad 100 for debris removal from the floor 10. Thus, the less absorbent polymer 108 can be used to meet cleaning pad absorbency requirements. In one embodiment, the pad 100 may include pockets in the middle portion along the length of the pad, allowing the superabsorbent polymer to expand into the pockets, and allowing the pad to maintain a constant thickness as the superabsorbent polymer expands.

In some embodiments, the dust-free layer 101, 102, 103 comprises a cellulose pulp nonwoven material that is bonded to the bicomponent fibers by air. In some examples, the wood pulp cellulose fibers are thermally bonded with a bicomponent polyethylene and/or polypropylene having a low melting point. The mixture forms a solid absorbent core that retains its formed shape and uniformly disperses the absorbed fluid, thereby preventing the cleaning liquid from pooling at the lowest point in the layer and preventing additional fluid accumulation. The airlaid layers 101, 102, 103 can be made from bleached wood pulp that looks like thick board. The pulp enters a hammer mill with blades on the rotor, which strikes the thick pulp and dampens (devibrate) it into individual fibers. The individual fibers enter a distributor having a screen rotor that looks like a flour screen. The fibers are formed into a sheet on another screen with an applied vacuum underneath, which sheet is mixed with a sheet of bicomponent fibers at this stage. The blown hot air melts the bicomponent to bond with the airlaid web.

The airlaid layer is positioned so as to distribute the absorbed liquid substantially uniformly throughout the core without the liquid puddling anywhere on the core layer (expansion. The mobile robot 400 sprays fluid 172 evenly in front of the robot and the pad 100 picks up evenly distributed applied solutions 173a, 173b along its length as it travels forward. In one embodiment, the airlaid layers 101, 102, 103 are bonded with a spray adhesive that is uniformly applied to the surface of the airlaid layers 101, 102, 103. In one embodiment, the adhesive is a polyolefin and is applied in a thin, uniform manner to achieve reliable adhesion without creating ridges and hard areas. The spray adhesive also creates a uniformly bonded surface interface that allows fluid to wick to the airlaid layers 101, 102, 103 without significant mechanical obstruction (e.g., stitching or relatively large impermeable patches or bumps), and this uniformly bonded surface interface between the airlaid layers 101, 102, 103 prevents puddling between the layers 101, 102, 103.

Very small amounts of acrylic latex adhesive can be micro-sprayed onto the surface to bond the outer layers and minimize flaking and help reduce linting. Lint is the condition that occurs when the entanglement of cotton, hemp or fibers is evident on an object or fabric. The airlaid layers 101, 102, 103 can include 15% biocomponent polymer, 85% cellulose, and latex on top to eliminate linting.

The wrapping layer 105 may be made of any material that is thin and absorbs fluids. In addition, the wrapping layer 105 may be smooth to prevent scratching the floor surface 10. In some embodiments, the cleaning pad 100 may include one or more of the following cleaning composition: butoxypropanol, alkylpolyglycosides, alkyldimethyl ammonium chloride, polyoxyethylated castor oil, linear alkylbenzenesulfonates, glycolic acid-which act as surfactants, for example, and attack scale and mineral deposition, among other things (ATTACK SCALE AND MINERAL deposits); and include odor, antibacterial or antifungal preservatives.

In some examples, the wrap 105 is a hydroentangled nonwoven material. Hydroentanglement may also be referred to as hydroentanglement, or hydraulic needling. Hydroentanglement is a process of entangling a web of loose fibers, typically formed from cards, on a porous belt or moving perforated or patterned screen to form a sheet structure by subjecting the fibers to multiple passes of fine high pressure water jets. Hydroentanglement processes enable the formation of specialty fabrics by the addition of fibrous materials such as tissue paper, air laid, hydroentangled, and spun-bonded nonwoven to composite nonwoven webs. These materials provide the performance advantages required for a variety of wiping applications due to their improved performance and cost structure.

Referring to fig. 2A and 2B, the hydroentangling process 200 includes a precursor web forming process 202A. The precursor web is typically made from textile-like staple fibers. These webs may be single webs or made from a number of different fiber blends. Typical four fiber options are polyester, viscose, polypropylene and cotton. Variants of each of these fibers may also be used, such as organic cotton as well as Lyocell material and Tencel rayon. Biodegradable PLA (polylactic acid) fibers may also be used.

The precursor web forming process 202a can include forming an airlaid comb that can be used to provide a more isotropic web due to the higher cross-machine direction orientation of the fibers. Carding is a method of making a thin web of parallel fibers. Higher bulk densities can also be obtained by using this type of carding system. Once the web of staple fibers is formed, a second layer of fibers can be placed on top of the substrate by air forming cellulosic fibers, or by "laminating" a preformed nonwoven web, such as tissue, hydroentanglement, or spunbonding. In some examples, the spunbond nonwoven material is combined with an airlaid layer, so the resulting fabric does not require a carding step of hydroentangled continuous fibers with cellulosic pulp fibers. The fiber composition then enters a fiber entanglement process 204 comprising a plurality of rows of high pressure water jets 210 which repeat the conventional mechanical needling process and individually entangle the fibers, thereby causing them to become entangled to form a web 212.

The hydroentangling process 200 includes applying a fiber entanglement process 204 to the fiber composition. The fiber entanglement process 204 includes spraying water from rows of high pressure water jets 210 to repeat the conventional mechanical needling process and individually entangle the fibers so that they become entangled to form a web 212. The web 212 (after passing through the web forming and carding process 202) is placed on a conveyor belt 214 rotated by two or more pulleys 216. During and/or after each water jet process, the mesh 212 passes through a suction 218 drum that sucks water from the fibers and allows the fibers to remain moving to the next high pressure water jet 210.

The consolidated nonwoven substrate 215 is then dried by an air dryer in an air dryer process 206 and then entangled in a entangling process 208.

The wrapping layer 105 may be embossed and hot embossed. Embossing and de-embossing (debosing) is a process that creates a raised or recessed design in a fabric or other material. Relatively low melting fibers such as polypropylene may be used to achieve better hot embossing. The coefficient of friction of the wrap 105 varies based on the type of surface and humidity. In one embodiment, the dry pad 100 moving over the glass has a coefficient of friction of about 0.4 to about 0.5 and the wet pad on the tile has a coefficient of friction of about 0.25 to about 0.4. The wrap 105 may include a water stamp that imparts a three-dimensional image onto the fabric. Water stamping is generally less expensive than thermal bonding. In one example, the wrapping layer 105 is embossed with a herringbone pattern. A wrapper 105 wrapped around the series of airlaid layers 101, 102, 103 enables the formation of an absorbent core that locks the absorbed fluid. Layering of the airlaid core layers 101, 102, 103 allows wicking and retention through the combined core and within each individual layer 101, 102, 103. In addition, the airlaid layers 101, 102, 103 that make up the core of the pad retain their shape while distributing fluid evenly throughout each fluid retaining layer and preventing pooling that might inhibit additional absorption.

The frayed meltblown layer 106 comprises meltblown fibers 107 formed by extruding a molten thermoplastic material through a plurality of fine, usually circular, die capillaries as molten threads or filaments into converging high velocity gas streams which cut the filaments of molten thermoplastic material to reduce their diameter. Thus, the meltblown fibers 107 are carried by the high velocity gas stream and are deposited on the surface of the collecting fibers, thereby forming a web of randomly distributed meltblown fibers 107.

In some examples, the frayed meltblown layer 106 is a layer of meltblown fibers 107 that provides a roughened surface. The meltblown fibers 107 are formed at high throughput by a meltblowing process 300 (see fig. 3) that produces foam or hair-like fibers formed from polymer flowing out of the die orifices due to temperature and other conditions of operation. An abrasive layer 106 is formed on top of the wrapping layer 105 (e.g., another meltblown layer, spunbond layer, or hydroentangled layer). The wrapping layer 105 may be a fish bone water embossed nonwoven material made from a ratio of viscose (rayon) fibers mixed with polyester fibers. In some examples, the abrasion meltblown layer 106 has a basis weight (also referred to as gram weight per square meter) equal to 55g/m ² (grams per square meter). The wrapper 105 may have a basis weight of between about 30gsm (grams per square meter) and about 65 gsm. In other examples, the wrapper may have a basis weight between about 35-40 gsm. Basis weight is a measurement used in the textile and paper industry to measure the mass per unit area of a product. In one embodiment, the wrap layer 105 is a hydroentangled spunbond or hydroentangled material formed with grooves (not shown) therein that allow fluid and suspended dirt to pass more directly to the airlaid layers 101, 102, 103 and reduce the amount of cohesive attraction between the wrap layer 105 and the floor surface 10 when the mat 100 is wet. In one embodiment, the grooves are chevron patterns. In another embodiment, the grooves form a square grid sized and spaced between 0.50 and 1.0 mm squares and spaced between 2.0 and 2.5 mm lengths in the grid formation. In one embodiment, the grooves are sized and spaced apart in squares of 0.75 millimeters and are spaced apart by a length of 2.25 millimeters in the grid formation. In another embodiment, the wrap 105 is a spunbond or hydroentangled material having needled holes therein for increasing the wicking ability of the wrap 105 and reducing the cohesion between the wet wrap 105 and the floor surface 10. The chevron, square and needled grooves prevent negative pressure from being created on the outside of the wrap by fluid evaporation and/or wicking from the back of the liner. Because there is no free movement within the wrap 105 or some texture on the wrap 105, the fluid applied to the floor surface 10 cannot replace the wicked fluid and it causes suction between the pad 100 and the floor. The combination of 35-40gsm of low density spunbond or hydroentangled material with surface texture in the form of hydraulically embossed grooves, surface texture and patterns (such as chevrons) or needled grooves or holes prevents suction between the mat and the floor. The meltblown layer 105 further helps to prevent this suction.

In addition, when the pad 100 is wet, there is insufficient fluid to lubricate the interface between the bottom surface of the pad and the floor surface 10. The fully wetted pad 100 will rest on a layer of fluid while the robot 400 is moving, but as the wet pad 100 slowly absorbs fluid, the insufficiently wetted, insufficiently lubricated wrap 106 will drag on the floor surface 10. In an embodiment, the spunbond or hydroentangled wrap 105 is made of hydrophilic fibers that minimize the surface area of the mat 100 that is exposed to air between the mat 100 and the floor surface 10. If the grooves or pinholes are not part of the wrap 100, the wet pad 100 will adhere to the hydrophilic floor surface 10. Spunbond or hydroentangled application of surface texture to the wrap 105 would otherwise promote surface tension of the wet pad 100 to the wet floor surface 10.

The weight of the abrasion meltblown layer 106 is such that the abrasion meltblown layer 106 acts as an absorbent layer and allows fluid to be absorbed through the meltblown layer 106 and retained by the airlaid layers 101, 102, 103. In some examples, the meltblown layer 106 covers about 60-70% of the surface area of the hydroentangled wrapping layer 105, and in other examples, the meltblown layer 106 covers about 50-60% of the surface area of the spunbond or hydroentangled wrapping layer 105.

The meltblown fibers 107 may have different arrangements and configurations on the hydroentangled wrapper 105. In some examples, the meltblown fibers 107 are randomly disposed on the wrapper layer 105. The meltblown fibers 107 may be disposed in one or more portions 109a-e on the cleaning surface 109. The cleaning surface 109 is the bottom surface of the cleaning pad 100 that is in contact with the floor surface 10. One or more portions 109a-e of the cleaning surface 109 have a coverage ratio between the meltblown abrasive fibers 107 and the wrapper 105 of greater than 50%. The meltblown layer provides the pad with the advantage of disrupting the surface tension that would otherwise cause the wet wrap to stick to the wet floor. By adding texture and topography to the floor facing surface of the mat, the meltblown layer prevents the mat from sticking to or encountering high drag forces. The meltblown layer also provides a surface texture to the mat for roughening dirt and debris to be adhered or dried to the floor surface and for loosening dirt and debris to be absorbed through the airlaid core of the mat.

As shown in fig. 3, the melt blowing process 300 is a process of extruding and drawing molten polymer resin using heated high velocity air 310 to form fibers or filaments 107. The fibers/filaments 107 cool and then form the web 106 on top of the moving screen 320. This process 300 is similar to spunbond, but the fibers 107 produced herein are finer and range in diameter from 0.1 to 20 microns (e.g., 0.1-5 microns). Meltblown is also known as a melt-spinning or spunbonding process. The process shown in fig. 3 illustrates extrusion die 312 (beam) extruding meltblown polypropylene fibers into a continuous porous conveyor to form nonwoven web 106. It consists of six main components: extruder, metering pump, extrusion die, net forming device, net reinforcing device and winding device. Other processes are also possible.

There are two basic die designs 312, single row dies and multiple rows of dies used with melt blowing techniques. The main difference between these two designs is the amount of air used and the throughput of the mold. Greater throughput can be achieved with multiple rows of dies. Multiple row dies typically have two to eighteen rows of holes, about three hundred holes per inch, whereas conventional single row dies have 25 to 35 holes per inch. Any of the die designs 312 may be used to form the meltblown fibers 107. The throughput of this process is much less than 200+ kg/hr/m (kg/hr/m) obtained for spunbond or hydroentanglement with its larger fiber diameter. Conventional dies can extrude substantially 70 to 90 kg/hr/m, while multiple rows of dies can reach about 160 kg/hr/m.

In some embodiments, the meltblown fibers 107 have a diameter between about 0.1 microns and about 5 microns, with an average of about 2.5 microns. Throughput and air flow have the greatest effect on reducing fiber diameter, with melting and air temperatures having less effect on die-to-forming table distance. Optimizing the process variables and using metallocene polypropylene can produce meltblown webs with average fiber diameters in the range of 0.3 to 0.5 microns and maximum fiber diameters less than 3 microns. By providing a very high head web with excellent air permeability, the wrap 104 of meltblown fibers 107 having this size can provide a barrier to liquid leakage from the cleaning pad 100. Meltblown fibers 107 may be created by using homo-polypropylene; however, other resins such as polyethylene, polyester, polyamide and polyvinyl alcohol may also be extruded through a melt blowing process. In some embodiments, the meltblown layer 106 is formed from polylactic acid (PLA), a biodegradable nonwoven.

In some examples, the airlaid layers 101, 102, 103, wear layer 104, and wrap layer 104 (i.e., cleaning pad 100) have a combined width W _T of between about 68 millimeters and about 80 millimeters, and a combined length (not shown) of between about 200 millimeters and about 212 millimeters. In some examples, the cleaning pad 100 including the airlaid layers 101, 102, 103, wear layer 104, and wrap layer 105 has a combined thickness T _T of between 6.5 millimeters and about 8.5 millimeters. Additionally or alternatively, the airlaid layers 101, 102, 103 have a combined airlaid width (W _A1+W_A2+W_A3) of between 69 millimeters and about 75 millimeters and a combined airlaid length (L _A1+L_A2+L_A3) of between about 165 millimeters and about 171 millimeters. The cleaning pad 100 can withstand the pressure applied to it by the tool 400, 500 (e.g., a robot or mop) because the tool 400, 500 will cause the cleaning pad 100 to simulate a scrubbing action back and forth as the robot 400 traverses the floor surface 10.

In some embodiments, while the cleaning pad 100 is cleaning the floor surface 10, it absorbs the cleaning fluid 172 applied to the floor surface 10. The cleaning pad 100 can absorb enough fluid without changing its shape. Thus, when the cleaning pad 100 is used in conjunction with the cleaning robot 400, the cleaning pad 100 has substantially similar dimensions before cleaning the floor surface 10 and after cleaning the floor surface 10. The cleaning pad 100 may increase in volume as it absorbs fluid. In some examples, the thickness T _T of the cleaning pad increases by less than 30% after fluid absorption.

In some embodiments, the wrap 104 has the specifications set forth in table 1 below:

TABLE 1

ASTM D3776M-09A and ASTM D5034-09 are standard tests from the American Society for Testing and Materials (ASTM). ASTM D3776M-09A covers the measurement of fabric mass per unit area (weight) and is applicable to most fabrics. ASTM D5034-09 (also known as the grab method) is a standard test method for breaking strength and elongation of fabrics. WSP 120.6 and WSP 10.0 (05) are standardized tests created by world strategic partners for testing nonwoven properties.

Referring to fig. 1A-1D, 3, 4-6, and 9A-9C, the cleaning pad 100 is configured to scrub the floor surface 10 and absorb fluid on the floor surface 10. In some examples, the cleaning pad 100 is connected to a cleaning tool such as a mobile robot 400 or a hand-held mop 500. The cleaning tools 400, 500 may include sprayers 462, 512 that spray the cleaning fluid 172 onto the floor surface 10. The tools 400, 500 are used to scrub and remove any stains (e.g., dirt, grease, food, sauce, coffee grounds) that are absorbed by the pad 100 along with the applied fluid 172 that dissolves and/or loosens the stain 22. Some stains may have viscoelastic properties that exhibit both viscous and elastic properties (e.g., honey). The cleaning pad 100 is absorbent and has an outer surface 105a that includes a randomly applied abrasive layer 106 containing meltblown fibers 107. As the tool 400, 500 moves around the floor surface 10, the cleaning pad 100 wipes the floor surface 10 with the abrasive side 105b of the abrasive layer 106b containing meltblown fibers and absorbs cleaning liquid sprayed onto the floor surface 10 with only a light weight force than would otherwise be required by wiping a mop with non-abrasive cleaning elements.

Referring to fig. 4, in some embodiments, the tool 400 is a compact lightweight autonomous mobile robot 400 that weighs less than 5 pounds and navigates and cleans the floor surface 10. The mobile robot 400 may include a body 410 supported by a drive system (not shown) that may maneuver the robot 400 across the floor surface 10 based on, for example, drive instructions having x, y, and q components. As shown, the robot body 410 has a square shape. However, body 410 may also have other shapes including, but not limited to, circular, oval, teardrop, rectangular, square, or a combination of a rectangular front and a circular back, or a longitudinally asymmetric combination of any of these shapes. The robot body 410 has a front 412 and a rear 414. The body 410 also includes a bottom portion (not shown) and a top portion 418. The bottom of the robot body 410 further includes one or more rear cliff sensors (not shown) in one or both of the two rear corners of the robot 400 and one or more front cliff sensors in one or both of the front corners of the mobile robot 400 for preventing falling from the protruding surface. In embodiments, the cliff sensor may be a mechanical drop sensor or a light-based proximity sensor, such as an IR (infrared) pair, a dual emitter, a single receiver or dual receiver, a single emitter, an IR light-based proximity sensor intended to be directed down the floor surface 10. In some examples, one or more front cliff sensors and one or more rear cliff sensors are placed at an angle relative to the front and rear corners, respectively, such that they cut the corners, span between the sidewalls of the robot 400 and cover the corners as much as possible to detect floor height changes beyond the threshold value accommodated by the existing reversible robot wheel drop. Placing cliff sensors close to the corners of robot 400 ensures that they will trigger immediately when robot 400 is suspended from the floor down and prevents the robot wheels from crossing the down edge.

In some embodiments, the front portion 412 of the body 410 is provided with a movable bumper 430 for detecting a collision in either a longitudinal (A, F) or transverse (L, R) direction. The bumper 430 has a shape that complements the robot body 410 and extends forward of the robot body 410 such that the overall size of the front portion 412 is wider than the rear portion 414 of the robot body 410 (the robot as shown has a square shape). The bottom of the robot body 410 supports the cleaning pad 100. In an embodiment, the pad 100 extends beyond the width of the bumper 430 such that the robot 400 can position the outer edge of the pad 100 up to tough and along it to a surface or access slit, such a wall-floor interface, and such that the surface or slit is cleaned by the extending edge of the pad 100, while the robot 400 moves in a wall-following manner. The embodiment of the pad 100 extending beyond the width of the bumper 430 enables the robot 400 to clean cracks and crevices outside the extent of the robot body 410. In an embodiment, such as shown in fig. 1A-1D, 8A-8C, and 9E, the mat 100 has been cut straight away from the end 100D such that the airlaid layers 101, 102, 103 are exposed at both ends 100D of the mat 100. In contrast to the wrap layer 105 sealing against the end 100d of the pad 100 and the ends 100d of the compressed air-laid layers 101, 102, 103, the full length of the pad 100 is available for fluid absorption and cleaning. Any portion of the airlaid core is not compressed by the wrapping layer 105 and therefore is not able to absorb the fluid 172. In addition, the disposable pad 100 of this embodiment will not have a saturated and moist, floppy end of the sealing wrap 105 upon completion of cleaning. All of the fluid 172 will be fixedly absorbed and held by the airlaid core, preventing any dripping and preventing the user from inadvertently touching the soiled wet end of the pad 100.

As shown in fig. 4 and 9A-9G, the robot 400 may be driven back and forth to cover a particular portion of the floor surface 10. As the robot 400 is driven back and forth, it cleans the area traversed and thus provides a deep scrub of the floor surface 10. The reservoir 475, which is contained by the robot body 410, holds the cleaning fluid 172 (i.e., cleaning liquid) and may contain 170-230 milliliters of fluid. In an embodiment, the reservoir 475 contains 200 milliliters of fluid. The robot 400 may include a fluid applicator 462 connected to a reservoir 475 via a tube. The fluid applicator 462 may be a sprayer having at least one nozzle 464 that dispenses fluid on the floor surface 10. The fluid applicator 462 may have a plurality of nozzles 464, each configured to spray fluid at an angle and distance different from the other nozzles 464. In some examples, the robot 400 includes two nozzles 464 vertically stacked in recesses in the fluid applicator 462 and angled and spaced such that one nozzle 464a sprays a relatively long length of fluid 172a forward and downward to cover an area in front of the robot 400 with a forward supply of applied fluid 173a, and the other nozzle 464b sprays a relatively short length of fluid 172b forward and downward such that a rearward supply of applied fluid 173b is on an area closer to the front of the robot 400 than an area of applied fluid 173a dispensed by the top nozzle 464 a. In an embodiment, the nozzles 464 or the nozzles 464a, 464b distribute the fluids 172, 172a, 172b in a pattern of areas that expands in size the robot width W _R and the at least one robot length L _R. In some embodiments, the top and bottom nozzles 464a, 464b apply fluid 172a, 172b in two different spaced apart strips of applied fluid 173a, 173b that do not extend the entire width W _R of the robot 400 such that the pad 100 passes over the outer edges of the strips of applied fluid 173a, 173b in a scrubbing action that is tilted forward and backward as described herein. In an embodiment, the strips of applied fluid 173a, 173b cover a combined length L _S of 75-95% of the width W _S of the robot width W _R and 75-95% of the robot length L _R. In some embodiments, the robot 400 sprays only on the traversing area of the floor surface 10.

In addition, the back and forth movement of the robot 400 breaks dirt on the floor surface 10. The broken stain is then absorbed by the cleaning pad 100. In some examples, if the cleaning pad 100 picks up too much liquid, such as the fluid 172, the cleaning pad 100 picks up enough spray fluid to avoid uneven streaking. In the event of too little fluid absorption, the robot 400 may leave fluid and wheel traces. In some embodiments, the cleaning pad 100 leaves a fluid residue, which may be water or some other cleaning agent (including solutions containing cleaning agents), to provide a visible shine on the floor surface 10 being scrubbed. In some examples, the fluid contains an antimicrobial solution, such as alcohol, containing a solution. Thus, the thin layer residue is intended not to be absorbed by the cleaning pad 100, allowing the fluid to kill a higher proportion of pathogens. Thus, the cleaning pad 100 does not swell or expand and provides a small increase in the total pad thickness T _T. This feature of the cleaning pad 100 prevents the robot 400 from tilting backward or falling forward if the cleaning pad 100 is inflated. The cleaning pad 100 has sufficient rigidity to support the front of the robot. In some examples, the cleaning pad 100 absorbs up to 180ml or 90% of the total fluid contained in the robotic reservoir 475. In some examples, the cleaning pad holds about 55 to about 60 milliliters of fluid, and the fully saturated wrap holds about 6 to about 8 milliliters of fluid 172. In some examples, the ratio of the air-laid core 101, 102, 103 to the liquid hold of the outer wrapper 105 is from about 9:1 to about 5:1.

The pad 100 and robot 400 are sized and shaped such that fluid transfer from the reservoir to the absorbent pad 100 maintains less than 5 pounds of fore-aft balance of the robot 400 during dynamic movement. The fluid distribution is designed such that the robot 400 continuously advances the pad 100 over the floor surface 10 without disturbing the increasingly saturated pad 100 and the diminishing fluid reservoir 475, lifting the back face 414 of the robot 400 and lowering the front face 412 of the robot 400 downward, and thereby applying a downward force to the robot 400 that inhibits movement. The robot 400 is able to move the pad 100 across the floor surface 10 even when the pad 100 is fully saturated with fluid. However, the robot 400 includes means to track the amount of floor surface 10 traveled and/or the amount of fluid remaining in the reservoir 475 and provide audible and/or visual alerts to the user: the pad 100 needs to be replaced and/or the reservoir 475 needs to be refilled. In an embodiment, if the pad 100 is fully saturated, the robot 400 stops moving and remains in place on the floor surface and there is still a floor to be cleaned once the pad 100 is replaced.

Figures 9A to 9G illustrate in detail the spraying, pad wetting and scrubbing actions of one embodiment of the mobile robot 400. In some embodiments, the robot 400 applies the fluid 172 only to areas of the floor surface 10 that the robot 100 has walked over. In one example, the fluid applicator 462 has a plurality of nozzles 464a, 464b, each configured to spray the fluid 172a, 172b in a different direction than the other nozzle 464a, 464 b. The fluid applicator 462 may apply the fluid 172 downward rather than outward, dropping or spraying the fluid 172 directly in front of the robot 100. In some examples, the fluid applicator 462 is a microfiber cloth or strip, a fluid dispensing brush, or a sprayer.

Referring to fig. 9A-9D and 9F-9G, in some embodiments, the robot 400 may perform a cleaning action by moving in a forward direction F toward the obstacle 20, followed by a rearward or reverse direction a. As shown in fig. 9A and 9B, the robot 400 may drive the first distance Fd to the first position L1 in the forward driving direction. When the robot 400 moves backward by the second distance Ad to the second position L2, the nozzles 464a, 464b spray the fluid 172a having a longer length and the fluid 172b having a shorter length simultaneously on the floor surface 10 in the forward and/or downward direction in front of the robot 400 after the robot 400 has moved at least the distance D in the area of the floor surface 10 that has been traversed in the forward driving direction F. In one example, the fluid 172 is applied to an area that is substantially equal to or less than the area footprint AF of the robot 400. Since the distance D is a distance that spans at least the length L _R of the robot 400, the robot 400 determines that the area traversed by the floor 10 is a clean floor surface 10 that is not occupied by furniture, walls 20, cliffs, carpeting, or other surfaces or obstacles to which the cleaning liquid 172 is to be applied if the robot 100 has not verified the presence of a clean floor surface 10 for receiving the cleaning liquid 172. By moving in the forward direction F and then rearward before applying the cleaning liquid 172, the robot 400 recognizes boundaries such as floor changes and walls and prevents fluids from damaging these items.

As shown in fig. 4, 9B, and 9C, in some examples, the fluid applicator 462 is a sprayer 462 that includes at least two nozzles 464a, 464B, each of which evenly distributes the fluid 172 across the floor surface 10 in two strips of applied fluid 173a, 173B. The two nozzles 464a, 464b are each configured to spray fluid at a different angle and distance than the other nozzle 464a, 464 b. In some examples, two nozzles 464a, 464b are vertically stacked in a recess in the fluid applicator 462 and are inclined and spaced apart from one another horizontally such that one nozzle 464a sprays a relatively long length of fluid 172a forward and downward to cover an area in front of the robot 400 with a forward-fed apply fluid 173a, while the other nozzle 464b sprays a relatively short length of fluid 172b forward and downward such that a rearward-fed apply fluid 173b is on an area closer to the front of the robot 400 than an area of apply fluid 173a dispensed by the top nozzle 464 a. In an embodiment, the nozzles 464 or the nozzles 464a, 464b distribute the fluids 172, 172a, 172b in a pattern of areas that expands in size the robot width W _R and the at least one robot length L _R. In some embodiments, the top and bottom nozzles 464a, 464b apply fluid 172a, 172b in two different spaced apart strips of applied fluid 173a, 173b that do not extend the entire width W _R of the robot 400 such that the pad 100 passes over the outer edges of the strips of applied fluid 173a, 173b in a scrubbing action that is tilted forward and backward as described herein. In an embodiment, the strips of applied fluid 173a, 173b cover a combined length L _S of 75-95% of the width W _S of the robot width W _R and 75-95% of the robot length L _R. In embodiments, the strips of applied fluid 173a, 173b may be generally rectangular or oval. In an embodiment, the nozzles 464a, 464b complete each spray cycle by drawing a small volume of fluid at the nozzle opening such that no fluid 172 leaks from the nozzle following each spray instance.

Referring to fig. 9D, 9F, and 9G, in some examples, the robot 400 may be driven back and forth to cover a particular portion of the floor surface 10, wet the cleaning pad 100 at the beginning of a cleaning operation, and/or scrub the floor surface 10. The robot 400 drives back and forth to clean the traversing area and thus provide thorough scrubbing of the floor surface 10. The robot 400 oscillates the attached pad 100 in a 12-15mm orbit to scrub the floor 10 and applies a downward pushing force of 1 pound or less to the pad.

In some examples, the fluid applicator 462 applies the fluid 172 to an area in front of the cleaning pad 100 and in a direction of travel (e.g., forward direction F) of the mobile robot 100. In some examples, the fluid 172 is applied to an area of the cleaning pad 100 that has previously been occupied. In some examples, the area that the cleaning pad 100 has occupied is recorded on a stored map that can be accessed to the robot controller 150 as shown in fig. 10. The robot 400 may include a cleaning system 1060 for cleaning or treating the floor surface 10.

In some examples, the robot 400 knows where it has been based on its place of coverage stored on a non-transitory memory 1054 of the robot 400 or on a map stored on an external storage medium accessible by the robot 400 through wired or wireless means during a cleaning run. The robot 400 sensor 5010 may include a camera and/or one or more ranging lasers for constructing a map of space. In some examples, the robot controller 1050 uses maps of walls, furniture, floor changes, and other obstacles 10 to position and place the robot 400 in a position sufficiently far from the obstacle and/or floor change prior to applying the cleaning liquid 172. This has the advantage of applying the fluid 172 to areas of the floor surface 10 that do not have known obstructions thereon.

In some examples, the robot 100 moves in a back and forth motion to wet the floor surface 10 to which the cleaning pad 100 and/or the scrubbing fluid 172 has been applied. The robot 400 may move in a pulse pattern through the footprint area AF on the floor surface 10 to which the fluid 172 has been applied. As shown, in some embodiments, the vein cleaning procedure involves moving the robot 100 in a forward direction F and a backward or reverse direction a along the center trajectory 1000 and in a forward direction F and a backward direction a along the left trajectory 1010 and the right trajectory 1005. In some examples, left track 1010 and right track 1005 are arcuate tracks that extend outwardly from a starting point in an arc along center track 1000. The left track 1010 and the right track 1005 may be straight tracks extending outward from the center track 1000 in straight lines.

Fig. 9D and 9F show two hundred pulse trajectories. In the example of fig. 9D, the robot 400 moves in a forward direction F along the center trajectory 1000 from position a until it encounters the wall 20 at position B and triggers a sensor 5010, such as a bump sensor. The robot 400 then moves in the rearward direction a along the center trajectory a distance equal to or greater than the distance covered by the fluid application. For example, the robot 400 moves backward along the center trajectory 1000 by at least one robot length l to a position G, which may be the same position as position a. The robot 400 applies the fluid 172 to an area substantially equal to or less than the footprint area AF of the robot 100 and returns to the wall 20, the cleaning pad 400 passes through the fluid 172 and cleans the floor surface 10. From position B, robot 100 retracts before returning to the positioning belt covering the remaining tracks, either along left track 1010 or along right track 1005. Each time the robot 400 moves forward and backward along the center, left, and right tracks 1000, 1010, 1005, the cleaning pad 100 passes through the application fluid 172, scrubbing dirt, debris, and other particulate matter from the floor surface 10 to which the fluid 172 is applied, and absorbing the dirty fluid into the cleaning pad 100 and away from the floor surface 10. The scrubbing action of the wet pad combined with the solvent properties of the cleaning liquid 172 breaks up and loosens dried stains and soils. The cleaning liquid 172 applied by the robot 400 suspends loose debris such that the cleaning pad 100 absorbs and wicks the suspended debris away from the floor surface 10.

In the example shown in fig. 9F, the robot 400 is also moved along the center trajectory 1000 from the starting position (position a) to the wall position (position B) by applying the fluid 172. The robot 400 exits the wall 20 along the center trajectory 1000 to a position C, which may be the same position as position a, extending to positions D and F before covering the left and right trajectories 1010, 1005, and the cleaning fluid 172 is dispensed by the cleaning pad 100 along the trajectories 1010, 1005. In one example, each time the robot 400 extends outward from the center trajectory 1000 along the trajectory, the robot 400 returns to the position indicated by positions A, C, E and G along the center trajectory, as shown in fig. 9F. In some embodiments, the robot 400 may vary the sequence of the backward a motion and the forward F motion along one or more different trajectories to move the cleaning pad 100 and cleaning fluid 172 across the floor surface in an effective and efficient coverage pattern.

In some examples, the robot 100 may move in a hundred-pulse coverage pattern to wet all portions of the cleaning pad 100 when starting a cleaning operation. As shown in fig. 9E, the bottom surface 100b of the cleaning pad 100 has a center region PC and right and left side edge regions PR and PL. When the robot 100 begins a cleaning run or cleaning procedure, the cleaning pad 100 is dry and needs to be wetted to reduce friction and also spread the cleaning fluid 172 along the floor surface 10 to scrub debris therefrom.

Thus, the robot 400 initially applies fluid at a high volumetric flow rate at the beginning of the cleaning operation so that the cleaning pad 100 is easily wetted. In one embodiment, the first volumetric flow rate is set by initially spraying about 1mL of fluid per 1.5 feet for a period of time, such as 1-3 minutes, and the second volumetric flow rate is set by spraying every 3 feet, where the volume of each sprayed fluid is less than 1 mL. In an embodiment, the robot 400 applies the fluid 172 every one to two feet at the beginning of the operation to saturate the wrapping layer 105 of the pad 100 early in the cleaning operation. After a period of time and/or distance, such as a duration of 2-10 minutes, the robot 400 applies fluid at every three to five feet interval because the pad 100 is wetted and is capable of scrubbing the floor 10. As shown in fig. 9G, in some examples, at the start of a cleaning operation, the robot 400 drives the cleaning pad 100 by applying the fluid 172 such that the center region PC of the bottom surface 100b of the cleaning pad 100 and the left and right side edge regions PR and PL of the cleaning pad 100 each individually pass through the application fluid 172, thereby wetting the entire cleaning pad 100 along the entire bottom surface 100b of the cleaning pad 100 in contact with the floor surface 10.

In the example of fig. 9G, the robot 400 moves along the center trajectory 1000 in the forward direction F and 10 and then the backward direction a by applying the fluid 172 through the center of the pad 100. Then, the robot 400 is driven in the forward direction F and the backward direction a along the right trajectory 1005, by applying the fluid 172 through the left region PL of the cleaning pad 100. Then, the robot 100 is driven in the forward direction F and the backward direction a along the left trajectory 1010 by applying the fluid 172 through the right region PR of the cleaning pad 100. At the start of a cleaning operation, the robot applies the fluid 172 at a relatively high initial volumetric flow rate Vi and/or a high initial frequency of application, more frequently applies a greater amount of the fluid 172 to the surface 10 and/or more frequently applies a fixed amount of the fluid 172 to the surface 10 to promptly wet the cleaning pad 100. Wetting the cleaning pad reduces friction and also enables the pad 100 to dissolve more debris 22 without requiring more frequent application of the fluid 172. In an embodiment, the coefficient of friction of the wrapping 105 of the mat 100 varies from 0.3 to 0.5 depending on the material of the floor 10 and the humidity of the mat 100. In one embodiment, the dry pad 100 moving over the glass has a coefficient of friction of about 0.4 to 0.5 and the wet pad on the tile has a coefficient of friction of about 0.25 to 0.4.

Once the wrapping layer 105 of the cleaning pad 100 is wetted, the robot 400 continues its cleaning operation and then applies the fluid 172 at the second volumetric flow rate Vf. This second volumetric flow rate Vf is relatively lower than the initial flow rate Vi at the start of the cleaning operation because the cleaning pad 100 has been wetted and effectively moves cleaning fluid over the surface 10 as it is scrubbed. In one embodiment, the initial volumetric flow rate Vi is set by initially spraying about 1mL of fluid per 1.5 feet for a period of time, such as 1-3 minutes, and the second volumetric flow rate Vf is set by spraying every 3 feet, where the volume of each sprayed fluid is less than 1 mL. The robot 400 adjusts the volumetric flow rate V such that a cleaning pad 100 of a given size is wetted onto the bottom surface 100b (fig. 9E) without being fully wetted to the maximum within the airlaid layers 101, 102, 103. The bottom surface 100b of the cleaning pad 100 is initially wetted without water accumulation within the absorbent interior of the pad 100 such that the cleaning pad 100 remains substantially absorbent for the remainder of the cleaning operation. The back and forth movement of the robot 400 breaks up the stains 22 on the floor surface 10. The broken stain 22 is then absorbed by the cleaning pad 100.

In some examples, the cleaning pad 100 picks up enough of the ejected fluid 172 to avoid uneven streaking. In some examples, the cleaning pad 100 leaves a solution residue to provide a visible shine to the floor surface 10 being scrubbed. In some examples, fluid 172 contains an antimicrobial solution; thus, the thin layer residue is intended not to be absorbed by the cleaning pad 100, allowing the fluid 172 to kill a higher proportion of pathogens.

In one embodiment, the pad may be flavored. The scents may be integrated into or applied to one or more of the airlaid core, the liner, or a combination of the airlaid layer and the liner. The fragrance may be inert during the pre-activation stage and activated by the fluid to release the fragrance so that the pad only generates fragrance during use, otherwise does not generate any odor upon storage. In another embodiment, the pad includes a cleaning agent or surfactant may be integrated into or applied to one or more of the airlaid core, the pad, or a combination of the airlaid layer and the pad. In one embodiment, the cleaning agent is applied only to the back side (unexposed, non-meltblown side) of the liner that is in contact with the lower most airlaid core member, such that the cleaning agent is released onto the cleaning surface through the porous liner upon contact with the fluid. The cleaning agent may be a foaming agent and/or cleaning agent having a pronounced gloss that indicates the application of the cleaning agent to the cleaning surface. In another embodiment, the pad includes one or more chemical preservatives applied to or manufactured within the paperboard backing element. The preservative is selected to prevent the growth of wood spores that may be present in the wood-based backing element. Some embodiments of the pad may include all of these features-conventional fragrances, cleaners, antibacterial agents and preservatives-or a lesser combination of all of these components, including encapsulated fragrances, for example.

Referring to fig. 5, in some examples, the tool 500 is a mop 500. Mop 500 includes a body 502 that supports a reservoir 504 holding cleaning fluid 172 (e.g., cleaning solution). A handle 506 is provided on one side of the body 502. The handle includes a controller 508 for controlling the release of fluid from the reservoir 504. A movable swivel base 510 is provided at the other end of the body 502 opposite the handle 506. The base 510 includes a fluid applicator 512 connected to the reservoir 504 by a tube (not shown). The fluid applicator 512 may be a sprayer having at least one nozzle 514 that dispenses fluid on the floor surface 10. The nozzles 514 spray forward and downward of the base 510 toward the floor surface 10. The user of the control 508 sprays the fluid 172 as desired. The fluid applicator 512 may have a plurality of nozzles 514, each configured to spray fluid in a different direction than the other nozzle 514.

Referring to fig. 6 and 8E-8G, the holders 600, 600a, 600b may be disposed on the tools 400, 500 supporting the cleaning pad 100. A holder 600, 600a, 600b is provided on the bottom of the tool 400, 500 for holding the cleaning pad 100. In one embodiment, retainer 600 may include hook and loop fasteners, and in another embodiment retainer 600 may include a clip or retention bracket and a selectively movable clip or retention bracket that selectively releases the pad for removal. Other types of retainers may be used to attach the cleaning pad 100 to the tool 400, 500 such as snaps, clips, brackets, adhesives, etc. which may be configured to allow release of the cleaning pad 100 when a pad release mechanism located on the tool 400, 500 is activated so that a user does not need to touch a dirty pad to remove the pad from the cleaning tool 400, 500.

Fig. 7 provides an exemplary arrangement of the operation of a method 700 of constructing a cleaning pad 100. The method 700 includes disposing 710 the first air-laid layer 101 on the second air-laid layer 102 and disposing 720 the second air-laid layer 102 on the third air-laid layer 103. The method 700 further includes wrapping 730 the wrap layer 104 around the first, second, and third airlaid layers 101, 102, 103. The wrapping layer 104 includes a hydroentangled wrapping layer 105 and a meltblown abrasive 107 adhered to the hydroentangled wrapping layer 105.

In some examples, the method 700 further includes adhering and randomly disposing the meltblown abrasive 107 onto the hydroentangled wrapping layer 105. Additionally or alternatively, the meltblown abrasive fibers may have a diameter of from about 0.1 microns to about 20 microns. The method 700 may further include disposing the meltblown abrasive and the hydroentangled wrapper 105 to have a collective thickness on the hydroentangled wrapper 105 of between 0.5 millimeters and about 0.7 millimeters. In some examples, the meltblown abrasive 107 creates a thickness gap of 0.5 millimeters between the wrap 105 and the floor 10. Due to this thickness gap, the pad 100 can pick up a 1.5 mm diameter bubble fluid on the floor 10 having surface tension without requiring force. The lowest point of the embossed cover 105 layer is only 0.5mm from the floor 10, while the remainder of the surface area of the wrap 105 is 3mm from the floor 10.

The method 700 may further include disposing the meltblown abrasive 107 on the hydroentangled wrapper 105 to provide a coverage surface ratio between the meltblown abrasive 107 and the hydroentangled wrapper 105 of between about 60% and about 70%. In some examples, method 700 may include adhering first airlaid layer 101 to second airlaid layer 102, and adhering second airlaid layer 102 to third airlaid layer 103. The airlaid layers 101, 102, 103 can be cellulose-based textile materials (e.g., materials including fluff pulp).

In some embodiments, the method 700 may include wherein the first, second, and third airlaid layers 101, 102, 103, the hydroentangled wrap 105, and the meltblown abrasive are configured to increase in thickness by less than 30% after fluid absorption. The method 700 may further include embossing the hydroentangled layer 105. The method 700 may also include disposing sodium polyacrylate in one or more of the airlaid layers 101, 102, 103.

In some examples, the method 700 further includes configuring the airlaid layers 101, 102, 103 and the wrap layer 104 to have a combined width of between about 80 millimeters and about 68 millimeters and a combined length of between about 200 millimeters and about 212 millimeters. The method 700 may further include configuring the airlaid layers 101, 102, 103 and the wrap layer 104 to have a combined width of between about 6.5 millimeters and about 8.5 millimeters. The method 700 may include configuring the airlaid layers 101, 102, 103 to have a combined airlaid width of between 69 millimeters and about 75 millimeters and a combined airlaid length of between about 165 millimeters and about 171 millimeters.

Fig. 8E-G illustrate an exemplary release mechanism for a pad 100 as described herein. Fig. 8A-8C illustrate an embodiment of a pad 100 having the cores of three airlaid layers 101, 102, 103 bonded and encapsulated in a wrap layer 105 adhered to the top surface of the top airlaid layer 101. In addition, the embodiment of fig. 8A-8C includes a paperboard backing layer 85 adhered to the top surface of the pad 100. The cardboard backing layer 85 protrudes beyond the longitudinal edge of the mat 100 and the protruding longitudinal edge 86 of the cardboard backing layer 85 attached to the mat holder 82 of the robot 100. In one embodiment, the cardboard backing layer 85 has a thickness of between 0.02 "and 0.03", a width of between 68 and 72 millimeters, and a length of between 90-94 millimeters. In one embodiment, the cardboard backing layer 85 is 0.026 "thick, 70 millimeters wide and 92 millimeters long. In one embodiment, the paperboard backing layer 85 is coated on both sides with a water-resistant coating, such as a wax or a polymer or a combination of water-resistant materials, such as wax/polyvinyl alcohol, polyamine, and the paperboard backing layer 85 does not disintegrate when wetted.

In an embodiment, the bottom surface 100b of the pad 100 may include one or more hair catching strips 100c for catching and collecting loose hair during the cleaning process. In the embodiment of fig. 9E, two hair catching bars 100c are shown in dashed lines to represent the optional nature of this function. In embodiments having one or more hair catching strips 100c, the strips 100c may be located on the outer longitudinal edge of the pad 100 or in a single strip down either longitudinal edge of the pad or in the middle of the pad. In an embodiment, each hair catching strip 100c is less than 30% of the total surface area of the bottom surface 100b of the pad 100, preferably less than 20% of the surface area of the bottom surface 100b of the pad 100. The hair catching strip 100c may be a strip material added to the wrapping layer 105, which includes loose fibers having a catching function, such asHooks, rough edge fibers, or fibers with a fused tip.

As shown in fig. 8E and 8G, the mat 100 as described herein may be secured to an autonomous robot by a mat holder 82 connectable to the robot 400. The example pad release mechanism 83 is also shown in an up or pad set position. The pad release mechanism 83 includes a retainer 600a or lip that securely holds the pad 100 in place by grasping the protruding longitudinal edge 86 of the cardboard backing layer 85. In the version shown, the tip or end 84 of the pad release mechanism 83 includes a movable retention clip 600a and an ejection protrusion 84 that slides upwardly through a slot or opening in the pad holder 82 as the pad is inserted into the holder 82 and pushed into a downward position as shown in fig. 8G to release the secured pad 100 (pushed down onto a connected backing layer 85, such as a cardboard backing as shown herein). The relationship between the pad and the pad holder 82 is also shown in the top view of fig. 8F. In one embodiment, the pad release mechanism 83 is activated by a toggle button 477 located below the handle 419 of the robot 400, as shown in fig. 4. The switching movement is indicated by a dashed double arrow 478. The toggle button 477 moves the spring actuator of the rotary pad release mechanism 83, moving the retaining clip 600a away from the cardboard backing layer 85 and moving the ejection tab 84 through the slot in the pad holder 882 such that the ejection tab pushes the pad 100 out of the holder.

Returning to fig. 8A and 8B, in an embodiment, the paperboard backing layer 85 may include a cutout 88 centered along the protruding longitudinal edge 86 of the paperboard backing layer 85 and corresponding in place with a protruding tab 94 on the bottom of the pad support 82, as shown in fig. 8D. In another embodiment, the paperboard backing layer 85 includes a first set of cuts 88 centered on the protruding longitudinal edge 86 of the paperboard backing layer 85 and a second set of cuts 90 on the lateral edges of the paperboard backing layer 85. The cutouts 88, 90 are symmetrically centered along the lateral central axis PCA _lon of the pad 100 and the longitudinal central axis PCA _lat of the pad 100 and engage with corresponding projections 92, 94 on the longitudinal central axis HCA _lon centered on the underside of the pad holder 82 and the lateral central axis PCA _lat of the underside of the pad holder 82. The pad holder 82 of the embodiment of fig. 8D includes three protruding protrusions 92, 94. This allows a user to mount the pad 100 in either of two identical directions (180 degrees relative to each other) while allowing the pad holder 82 to more easily release the pad 100 when the release mechanism 83 is triggered. Other embodiments of the pad holder include four protrusions 92, 94 in place corresponding to the four cutouts 88, 90 in the cardboard backing layer shown in fig. 8C. In other embodiments, pad holder 82 and pad 100 each include any other number or configuration of protruding protrusions and corresponding cutouts for holding the pad in place and capable of being selectively released.

In fig. 8D, the protruding tabs 94 on the longitudinal edges of the pad holder 82 are obscured by the holding holder 600a, which is shown in phantom view, such that the protruding tabs 94 thereunder are visible in the exemplary view. Both protrusions 92, 94 clamp the disposable pad 100 to the bottom of the pad holder 82 such that alignment of the pad 100 with the holder 82 is precise and the pad 100 is held stationary relative to the pad holder 82 by preventing lateral and/or transverse sliding.

Because the slits 88, 90 extend into the surface area of the paperboard backing layer 85, they interface with more of the lateral and longitudinal surface areas of the protruding tabs 92, 94, respectively, and the pad is also held in place against rotational forces by the slit tab retention system. As described above, the robot 100 moves in a scrubbing motion, and in an embodiment, the pad support 82 oscillates the pad for additional scrubbing. In an embodiment, the robot 400 oscillates the attached pad 100 in a 12-15mm orbit to scrub the floor 10 and applies a downward pushing force of 1 pound or less to the pad. By aligning the cutouts 88, 90 in the cardboard backing layer 85 with the protrusions 92, 94, the pad 100 remains stationary relative to the mount during use, and an applied scrubbing action (including a shaking action) is transferred directly from the pad mount 82 through the layer of pad without losing the transferred motion.

In an embodiment, the pad of fig. 1A-1D and 8A-8C is a disposable pad. In other embodiments, the pad 100 is a reusable microfiber cloth pad having the same absorbent characteristics as those described herein with respect to the embodiments. In embodiments with washable, reusable microfiber cloths, the top surface of the cloth includes a fixed rigid backing layer shaped and positioned to image the paperboard backing layer of the embodiment of fig. 8A-8C. The rigid backing layer is made of a heat resistant, washable material that can be mechanically dried without melting or degrading the backing. The rigid backing layer is of a certain size and has a cutout as described herein used interchangeably with the embodiment of the pad support 82 described with respect to the embodiment of fig. 8A-8G.

In other examples, the pad 100 is intended to be used as a disposable dry cloth and includes a single layer of needle punched spunbond or hydroentangled material exposing fibers for hair entrapment. The dry pad 100 embodiment also includes a chemical treatment that adds a tacky nature to the pad 100 for holding dirt and debris. In one embodiment, the chemical treatment is a commercially available material such as that sold under the trade name DRAKESOL.

Some embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims. For example, the actions recited in the claims can be performed in a different order and still achieve desirable results.

Claims

1. A mobile floor cleaning robot comprising:

a driver supporting the robot main body to maneuver the cleaning robot on the floor surface; and

A cleaning assembly provided in a robot main body and including a pad holder provided on a front portion of a driving wheel of the cleaning robot, the pad holder including:

A top portion of the base plate,

A base having a bottom surface disposed 0.5 cm to 1.5 cm from the floor surface and configured to receive a cleaning pad, the surface area of the bottom surface of the pad holder being at least 40% of the surface area of the robot footprint, and

A plurality of protrusions extending from a bottom surface of the bottom of the pad support, the plurality of protrusions configured for engagement with mating slots on the cleaning pad to align a received cleaning pad with the pad support, and

A release mechanism holding the received cleaning pad along the bottom of the pad holder, the release mechanism being configured to eject the received cleaning pad from the bottom of the pad holder upon actuation of the release mechanism, wherein an end of the release mechanism includes a movable retaining clip and an ejection protrusion, the retaining clip securely holding the cleaning pad in place by grasping a protruding longitudinal edge of the backing layer of the cleaning pad.

2. The cleaning robot of claim 1, wherein the pad holder is configured to engage with a backing layer of a received cleaning pad.

3. The cleaning robot of claim 2, wherein at least one protrusion on the bottom of the pad holder is positioned to align with and engage a shaped slot of the backing layer.

4. The cleaning robot of claim 1, wherein the cleaning assembly comprises:

A reservoir holding a volume of fluid; and

A fluid applicator in fluid communication with the reservoir, the fluid applicator configured to apply fluid along a forward drive direction of the cleaning robot and in front of the pad support.

5. The cleaning robot of claim 4, wherein the fluid applicator comprises at least two nozzles for applying fluid in two strips on the floor surface in a forward driving direction of the cleaning robot, wherein each of the two strips of applied fluid distributes the fluid evenly over the entire floor surface,

Wherein the at least two nozzles are vertically stacked in a recess in the fluid applicator and are angled with respect to the horizontal to spray fluid forward and downward,

Wherein a first nozzle of the at least two nozzles sprays fluid at an angle relative to a horizontal plane to cover a first area on the floor surface, a second nozzle of the at least two nozzles sprays fluid at an angle relative to the horizontal plane to cover a second area of the floor surface, and the first nozzle of the at least two nozzles and the second nozzle of the at least two nozzles are spaced apart from each other such that the first area is forward of the second area,

The fluid applicator is configured to dispense fluid through the at least two nozzles in a pattern of zones that expands the robot width and at least one robot length.

6. The cleaning robot of claim 4, wherein the received cleaning pad is configured to absorb 90% of the volume of fluid held in the reservoir.

7. The cleaning robot of claim 1, further comprising a fluid applicator and at least two nozzles for applying fluid in two strips on the floor surface in a forward driving direction of the cleaning robot, wherein each of the two strips of applied fluid distributes fluid evenly over the entire floor surface,

Wherein a first nozzle of the at least two nozzles sprays fluid at an angle relative to a horizontal plane to cover a first area on the floor surface, a second nozzle of the at least two nozzles sprays fluid at an angle relative to the horizontal plane to cover a second area of the floor surface, and the first nozzle of the at least two nozzles and the second nozzle of the at least two nozzles are spaced apart from each other such that the first area is forward of the second area.

8. The cleaning robot of claim 4, wherein the total weight of the cleaning robot with the reservoir empty is between 1kg and 1.5kg, and the total weight of the cleaning robot with the reservoir having fluid is between 1.5kg and 4.5 kg.

9. The cleaning robot of claim 4, wherein the cleaning robot is configured to apply fluid to the floor surface to wet the received cleaning pad at an initial volumetric flow rate that is relatively higher when the received cleaning pad is wetted than a subsequent volumetric flow rate.

10. The cleaning robot of claim 9, wherein:

the initial volumetric flow rate is set by spraying 1 milliliter of fluid per 30 centimeters over 1-3 minutes,

The subsequent volumetric flow rates were set by spraying every 3 feet, and

Each fluid spray at the initial volumetric flow rate and at the subsequent volumetric flow rate is less than 1 milliliter.

11. The cleaning robot of claim 1, wherein the driver is configured to maneuver the cleaning robot in a hundred-pulse motion in which the cleaning robot moves forward and backward along a center trajectory, forward and backward to the left along the trajectory and away from the starting point along the center trajectory, and forward and backward to the right along the trajectory and away from the starting point along the center trajectory.

12. The cleaning robot of claim 1, wherein the cleaning robot body defines a substantially rectangular footprint and the cleaning robot pad support defines a substantially rectangular footprint.

13. The cleaning robot of claim 1, wherein the cleaning assembly further comprises a post disposed on top of the pad support, the post sized for receipt by a corresponding aperture defined by the cleaning robot body.

14. The cleaning robot of claim 13, wherein the post has a cross-sectional diameter that varies along a length of the post.

15. The cleaning robot of claim 13, wherein the post comprises a vibration damping material.

16. The cleaning robot of claim 1, further comprising an arm extending from a front of the drive body, the arm being pivotally connected to the robot body in front of the drive wheel to allow the drive wheel to move vertically relative to the floor surface.