Cleaning Apparatus with Combing Unit for Removing Debris from Cleaning Roller

The present application is a continuation of U.S. patent application Ser. No. 18/131,247 filed Apr. 5, 2023, which is a continuation of U.S. patent application Ser. No. 15/492,320 filed Apr. 20, 2017 which claims the benefit of U.S. Provisional Application No. 62/469,853, filed Mar. 10, 2017 and is a continuation-in-part of U.S. patent application Ser. No. 15/331,045, filed Oct. 21, 2016, which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/244,331 filed Oct. 21, 2015, U.S. Provisional Patent Application Ser. No. 62/248,813 filed Oct. 30, 2015, and U.S. Provisional Patent Application Ser. No. 62/313,394 filed Mar. 25, 2016, all of which are fully incorporated herein by reference. U.S. application Ser. No. 15/492,320 is also a continuation-in-part of International Application No. PCT/US2016/058148, filed on Oct. 21, 2016, which is fully incorporated herein by reference.

The present disclosure relates to cleaners with cleaning rollers and more particularly, to a cleaning apparatus, such as a surface cleaning head for a vacuum cleaner, with a combing unit for removing debris from a cleaning roller such as a leading roller.

Vacuum cleaners generally include a suction conduit with an opening on the underside of a surface cleaning head for drawing air (and debris) into and through the surface cleaning head. One of the challenges with vacuum cleaner design is to control engagement of the suction conduit with a surface being cleaned to provide the desired amount of suction. If the suction conduit is spaced too far from a surface, the suction may be less because the air is flowing into the suction conduit through a greater surface area. If the suction conduit is directly engaged with the surface and thus sealed on all sides, air will stop flowing into the suction conduit and the suction motor may be damaged as a result.

Vacuum cleaners also generally use agitation to loosen debris and facilitate capturing the debris in the flow of air into the suction conduit. Agitators are often used in the suction conduit of a surface cleaning head proximate a dirty air inlet to cause the agitated debris to flow into the dirty air inlet. If the agitator in the suction conduit is unable to loosen the debris or if the debris is too small, the suction conduit may pass over the debris without removing the debris from the surface. In other cases, the surface cleaning head may push larger debris forward without ever allowing the debris to be captured in the flow into the suction conduit (sometimes referred to as snowplowing).

One example of an agitator is a cleaning roller such as a brush roll. A cleaning roller may be located within a suction conduit and/or may be located at a leading side of a suction conduit (e.g., a leading roller). One challenge with a leading roller in particular is the debris (e.g., hair) that becomes entangled around the roller. Projections may be used to engage the roller to facilitate removal of debris, but existing structures are often not effective and/or interfere with the operation of the surface cleaning head.

Consistent with an embodiment, a cleaning apparatus includes a housing defining an opening on an underside of the housing for receiving debris, a cleaning roller mounted in the housing for directing debris into the opening, and a combing unit extending a substantial length of a cleaning surface of the cleaning roller and in contact with the cleaning roller. The combing unit includes a series of spaced combing protrusions extending partially into the cleaning roller and having angled leading edges that are not aligned with a center of rotation of the cleaning roller. The angled leading edges are directed into a direction of rotation of the cleaning roller.

Consistent with another embodiment, a surface cleaning head includes a housing having a front side and back side. The housing defines a suction conduit with an opening on an underside of the housing between the front side and the back side. A brush roll is rotatably mounted to the housing within the suction conduit and at least a portion of the brush roll is proximate the opening of the suction conduit. A leading roller is mounted to the housing in front of the brush roll and adjacent the opening of the suction conduit. A front portion of the leading roller is at least partially exposed at the front side of the housing. The surface cleaning head also includes a combing unit extending a substantial length of a cleaning surface of the leading roller and in contact with the leading roller. The combing unit includes a series of spaced combing protrusions extending partially into the leading roller and having angled leading edges that are not aligned with a center of rotation of the leading roller. The angled leading edges are directed toward a direction of rotation of the leading roller.

A cleaning apparatus, consistent with embodiments of the present disclosure, includes a combing unit (also referred to as a debriding unit or rib) including a series of spaced protrusions or teeth extending into a cleaning roller for preventing build up and removing debris (such as hair, string, and the like). The protrusions extend along a substantial portion of the cleaning roller and extend partially into the cleaning roller to intercept the debris as it passes around the roller. The protrusions have angled leading edges that are not aligned with a rotation center of the cleaning roller and are directed into or against a direction of rotation of the cleaning roller. The combing unit and protrusions have a shape and configuration designed to facilitate debris removal from the cleaning roller with minimal impact on the operation of the cleaning apparatus. The cleaning apparatus may include a surface cleaning head of an upright vacuum cleaner or sweeper or a robotic vacuum cleaner.

An embodiment of a surface cleaning head may include dual rotating agitators (e.g., a leading roller and a brush roll) and may be used to facilitate capturing of debris in the air flow into a suction conduit on the underside of the surface cleaning head. In this embodiment, the leading roller is generally positioned adjacent to and in advance of the opening of the suction conduit such that the leading roller engages debris and moves the debris toward the opening. At least a top half of the leading roller may be substantially outside of the flow path to the suction conduit and a bottom portion of the leading roller may be exposed to the flow path to the suction conduit. The rotating brush roll may be located in the suction conduit with the leading roller located in front of and spaced from the brush roll, forming an inter-roller air passageway between lower portions of the leading roller and the brush roll. In some embodiments, combing protrusions may contact the leading roller above the inter-roller air passageway to facilitate debris removal into the flow path. The surface cleaning head may also include a leading bumper that extends in front of the leading roller to protect a front portion of the leading roller and facilitate front edge cleaning.

Although specific embodiments of a surface cleaning head with a leading roller are shown, other embodiments of a cleaning apparatus with a combing unit are within the scope of the present disclosure. The cleaning apparatus with the combing unit may be used in different types of vacuum cleaners including, without limitation, an “all in the head” type vacuum, upright vacuum cleaners, canister vacuum cleaners, stick vacuum cleaners, robotic vacuum cleaners and central vacuum systems, and may be used in sweepers (e.g., low or no suction). The surface cleaning head with a leading roller may also include removable agitators (e.g., brush rolls) in openable agitator chambers, such as the type described in greater detail in U.S. Pat. No. 9,456,723 and U.S. Patent Application Pub. No. 2016/0220082, which are commonly-owned and fully incorporated herein by reference. The leading roller may be similarly removable.

As used herein, a “surface cleaning head” refers to a device configured to contact a surface for cleaning the surface by use of suction air flow, agitation, or a combination thereof. A surface cleaning head may be pivotably or steeringly coupled by a swivel connection to a wand for controlling the surface cleaning head and may include motorized attachments as well as fixed surface cleaning heads. A surface cleaning head may also be operable without a wand or handle. As used herein, “seal” or “sealing” refers to preventing a substantial amount of air from passing through to the suction conduit but does not require an air tight seal. As used herein, “agitator” refers to any element, member or structure capable of agitating a surface to facilitate movement of debris into a suction air flow in a surface cleaning head. As used herein, “soft” and “softer” refer to the characteristics of a cleaning element being more compliant or pliable than another cleaning element. As used herein, the term “flow path” refers to the path taken by air as it flows into a suction conduit when drawn in by suction. As used herein, the terms “above” and “below” are used relative to an orientation of the surface cleaning head on a surface to be cleaned and the terms “front” and “back” are used relative to a direction that a user pushes the surface cleaning head on a surface being cleaned (i.e., back to front). As used herein, the term “leading” refers to a position in front of at least another component but does not necessarily mean in front of all other components.

Referring to, an embodiment of a surface cleaning headwith dual agitators and a combing unit is shown and described. The surface cleaning headincludes a housingwith a front side, and a back side, left and right sides,, an upper side, and a lower or under side. The housingdefines a suction conduithaving an openingon the undersideof the housing (shown in). The suction conduitis fluidly coupled to a dirty air inlet, which leads to a suction motor (not shown) either in the surface cleaning heador another location in the vacuum. The suction conduitis the interior space defined by interior walls in the housing, which receives and directs air drawn in by suction, and the openingis where the suction conduitmeets the undersideof the housing.

The surface cleaning headincludes dual rotating agitators,, for example, a brush rolland a leading roller. The brush rolland leading rollermay be configured to rotate about first and second rotating axes (RA, RA). The rotating brush rollis at least partially disposed within the suction conduit(shown in). The leading rolleris positioned in front of and spaced from the brush rolland at least substantially outside the suction conduit. In some embodiments, at least an inside upper portion (e.g., upper half) of the leading rolleris not exposed to the primary air flow path (e.g., arrow) into the openingof the suction conduitwhile at least an inside of the bottom portion of the leading rolleris exposed to the primary flow path into the openingof the suction conduit.

Other variations are possible where different portions of the leading rollermay be exposed or not exposed to the flow path into the suction conduit. In other embodiments, for example, a flow path may allow air to flow over the upper portion of the leading roller. The leading rollermay rotate about the second rotation axis RAlocated within a leading roller chamber. The leading roller chambermay have a size and shape slightly larger than the cylindrical projection of the leading rollerwhen the leading rolleris rotating therein, for example, to form the flow path over the upper portion.

The surface cleaning headmay include one or more wheelsfor supporting the housing on the surfaceto be cleaned. The brush rollmay be disposed in front of one or more wheels,(see) for supporting the housingon the surfaceto be cleaned. For example, one or more larger wheelsmay be disposed along the back sideand/or one or more smaller middle wheelsmay be provided at a middle section on the undersideof the housingand/or along the left and right sides,. Other wheel configurations may also be used. The wheels,facilitate moving the surface cleaning headalong the surfaceto be cleaned, and may also allow the user to easily tilt or pivot the surface cleaning head(e.g., brush rolland/or the leading roller) off of the surfaceto be cleaned. The rear wheel(s)and the middle wheel(s)may provide the primary contact with the surface being cleaned and thus primarily support the surface cleaning head. When the surface cleaning headis positioned on the surfacebeing cleaned, the leading rollermay also rest on the surfacebeing cleaned. In other embodiments, the leading rollermay be positioned such that the leading rollersits just above the surface being cleaned.

The rotating brush rollmay have bristles, fabric, or other cleaning elements, or any combination thereof around the outside of the brush roll. Examples of brush rolls and other agitators are shown and described in greater detail in U.S. Pat. No. 9,456,723 and U.S. Patent Application Pub. No. 2016/0220082, which are fully incorporated herein by reference.

The leading rollermay include a relatively soft material (e.g., soft bristles, fabric, felt, nap or pile) arranged in a pattern (e.g., a spiral pattern) to facilitate capturing debris, as will be described in greater detail below. The leading rollermay be selected to be substantially softer than that of the brush roll. The softness, length, diameter, arrangement, and resiliency of the bristles and/or pile of the leading rollermay be selected to form a seal with a hard surface (e.g., but not limited to, a hard wood floor, tile floor, laminate floor, or the like), whereas the bristles of the brush rollmay selected to agitate carpet fibers or the like. For example, the leading rollermay be at least 25% softer than the brush roll, alternatively the leading rollermay be at least 30% softer than the brush roll, alternatively the leading rollermay be at least 35% softer than the brush roll, alternatively the leading rollermay be at least 40% softer than the brush roll, alternatively the leading rollermay be at least 50% softer than the brush roll, alternatively the leading rollermay be at least 60% softer than the brush roll. Softness may be determined, for example, based on the pliability of the bristles or pile being used.

The size and shape of the bristles and/or pile may be selected based on the intended application. For example, the leading rollermay include bristles and/or pile having a length of between 5 to 15 mm (e.g., 7 to 12 mm) and may have a diameter of 0.01 to 0.04 mm (e.g., 0.01-0.03 mm). According to one embodiment, the bristles and/or pile may have a length of 9 mm and a diameter of 0.02 mm. The bristles and/or pile may have any shape. For example, the bristles and/or pile may be linear, arcuate, and/or may have a compound shape. According to one embodiment, the bristles and/or pile may have a generally U and/or Y shape. The U and/or Y shaped bristles and/or pile may increase the number of points contacting the floor surface, thereby enhancing sweeping function of leading roller. The bristles and/or pile may be made on any material such as, but not limited to, Nylon 6 or Nylon 6/6.

Optionally, the bristles and/or pile of leading rollermay be heat treated, for example, using a post weave heat treatment. The heat treatment may increase the lifespan of the bristles and/or pile of the leading roller. For example, after weaving the fibers and cutting the velvet into rolls, the velvet may be rolled up and then run through a steam rich autoclave making the fibers/bristles more resilient fibers.

The leading rollermay have an outside diameter Dlr that is smaller than the outside diameter Dbr of the brush roll. For example, the diameter Dlr may be greater than zero and less than or equal to 0.8 Dbr, greater than zero and less than or equal to 0.7 Dbr, or greater than zero and less than or equal to 0.6 Dbr. According to example embodiments, the diameter Dlr may be in the range of 0.3 Dbr to 0.8 Dbr, in the range of 0.4 Dbr to 0.8 Dbr, in the range of 0.3 Dbr to 0.7 Dbr, or in the range of 0.4 Dbr to 0.7 Dbr. As an illustrative example, the brush rollmay have an outside diameter of 48 mm and the leading rollermay have an outside diameter of 30 mm. While the leading rollermay have an outside diameter Dlr that is smaller than the outside diameter Dbr of the brush roll, the brush rollmay have bristles that are longer than the bristle and/or pile of the leading roller.

Positioning a leading roller(having a diameter Dlr that is smaller than the diameter Dbr of the brush roll) in front of the brush rollprovides numerous benefits. For example, this arrangement decreases the height of the front sideof the surface cleaning head(e.g., the housing) from the surfaceto be cleaned. The decreased height of the front of the surface cleaning headprovides a lower profile that allows the surface cleaning headto fit under objects (e.g., furniture and/or cabinets). Moreover, the lower height allows for the addition of one or more light sources(such as, but not limited to, LEDs), while still allowing the surface cleaning headto fit under objects.

Additionally, the smaller diameter Dlr of the leading rollerallows the rotating axis of the leading rollerto be placed closer to the front sideof the surface cleaning head. When rotating, the leading rollerforms a generally cylindrical projection having a radius that is based on the overall diameter of the leading roller. As the diameter of the leading rollerdecreases, the bottom contact surface() of the leading rollermoves forward towards the front sideof the surface cleaning head. In addition, when the surface cleaning headcontacts a vertical surface(e.g., but not limited to, a wall, trim, and/or cabinet), the bottom contact surfaceof the leading rolleris also closer to the vertical surface, thereby enhancing the front edge cleaning of the surface cleaning headcompared to a larger diameter leading roller. Moreover, the smaller diameter Dlr of the leading rolleralso reduces the load/drag on the motor driving the leading roller, thereby enhancing the lifespan of the motor and/or allowing a smaller motor to be used to rotate both the brush rolland leading roller.

The rotating brush rollmay be coupled to an electrical motor (either AC or DC) to cause the rotating brush rollto rotate about the first rotating axis. The rotating brush roll may be coupled to the electrical motor by way of a gears and/or drive belts. The leading rollermay be driven from the same drive mechanism used to drive the rotating brush rollor a separate drive mechanism. An example of the drive mechanism is described in U.S. patent application Ser. No. 15/331,045, filed Oct. 21, 2016, which is incorporated herein by reference. Other drive mechanisms are possible and within the scope of the present disclosure.

In at least one embodiment, the brush rolland the leading rollerrotate in the same direction directing debris toward the suction conduit, for example, counter clockwise as shown in. This arrangement may reduce the number of parts (e.g., no clutch or additional gear train may be necessary), thereby making the surface cleaning headlighter, reducing drivetrain loss (thereby allowing for smaller/less expensive motors), and less expensive to manufacture. Optionally, the brush rolland the leading rollermay rotate at same speed, thereby reducing the number of parts (e.g., no additional gear train necessary) and reducing drivetrain loss (thus, smaller/less expensive motor) and making the surface cleaning headlighter and less expensive to manufacture.

As shown in, the leading rollermay be positioned within the housingsuch that the bottom contact surfaceis disposed closer to the surfaceto be cleaned compared to the bottom contact surfaceof the brush roll. This arrangement allows the leading rollerto contact a surface(e.g., a hard surface) without the brush rollcontacting the hard surface. As may be appreciated, the leading rolleris intended to pick up debris from a hard surfacewhile the brush rollis intended to primarily contact a carpet surface. This arrangement is therefore beneficial since it allows the leading rollerto form a seal between the frontof the surface cleaning headwith the hard surface, thereby enhancing airflow and suction with the hard surface. Additionally, this arrangement reduces the drag/torque on the drive motor(s) since the brush roll(in some embodiments) does not have to contact the hard surface. The reduced drag/torque may allow for a smaller, less expensive motor and/or may increase the lifespan of the motor.

According to some embodiments, as shown in, the leading rolleris spaced apart a distance L(which is greater than 0 mm) from the brush rollsuch that the leading rollerdoes not contact the brush roll. The distance Lallows for an inter-roller vacuum passagewaybetween lower portions of the brush rolland the leading roller, which provides at least a portion of the flow path into the openingof the suction conduit. The inter-roller vacuum passagewayallows for debris that is either picked up by (and/or removed from) the leading rollerto be entrained in the vacuum flow generated by the surface cleaning headand/or to be picked up by the brush roll, thereby enhancing the cleaning efficiency of the surface cleaning head. Additionally, the distance Lreduces the load/drag on the motor(s), thereby enhancing the lifespan of the motor(s) and/or allowing smaller motors to be used to rotate both the brush rolland the leading roller.

One or both of the leading rollerand the brush rollmay be removable. The leading rollermay be removably coupled to the housingof the surface cleaning head. For example, a portion of the housing(such as, but not limited to, a portion of the left and/or right side,) may be removably/hingedly coupled thereto. To remove the leading roller, the removable portion may be unsecured/uncoupled from the rest of the housing, thereby allowing the leading rollerto disengage from a drive wheel and allowing the leading rollerto be removed from the leading roller chamber. Other ways of removably coupling the leading rollerwithin the housingare also possible and within the scope of the present disclosure.

In some embodiments, the housingof the surface cleaning headmay include a removable and/or hinged panel that allows the brush rollto be removed. A shown in, for example, the surface cleaning headincludes a panelthat may be removably and/or hingedly coupled to the housing. To remove the brush roll, the panelmay be disengaged from the housing(e.g., removed) to allow the user to have access to a brush roll chamber. Examples of removable panels or covers and removable brush rolls are described in greater detail in U.S. Pat. No. 9,456,723 and U.S. patent application Pub. No. 2016/0220082, which are fully incorporated herein by reference. Alternatively or additionally, the leading rollermay be removable in the same way. Another example of a removable leading roller is described in U.S. patent application Ser. No. 15/331,045, filed Oct. 21, 2016, which is incorporated herein by reference.

The ability to remove the brush rolland/or the leading rollerfrom the surface cleaning headallows the brush rolland/or the leading rollerto be cleaned more easily and may allow the user to change the size of the brush rolland/or the leading roller, change type of bristles on the brush rolland/or the leading roller, and/or remove the brush rolland/or the leading rollerentirely depending on the intended application.

In some embodiments, the surface cleaning headmay also include a series of combing protrusions(also referred to as debriding protrusions) in contact with the leading roller, as shown in greater detail in. The combing protrusionsmay be configured to remove debris (such as, but not limited to, hair, string, and the like) that may be wrapped around and/or entrapped/entrained in/on the leading rolleras the surface cleaning headis being used (e.g., without the user having to manually remove the debris from the leading roller). According to one embodiment, the combing protrusionsmay contact only the leading roller(e.g., the combing protrusionsmay not contact the brush roll). Some of the benefits of the combing protrusionsonly contacting the leading rollerinclude increasing the lifespan of the leading roller. Additionally, the combing protrusionsthat only contact the leading rollermay reduce the load/drag on the motor, thereby allowing a smaller/less expensive motor to be used and making the surface cleaning headlighter and less expensive to manufacture.

In this embodiment, the combing protrusionsmay include a plurality of spaced ribswith angled edgesextending into contact with a surface of the leading roller. The spaced ribsextend from a back supportwith base portionslocated therebetween to reinforce the spaced ribs. The back supportmay be mounted within the leading roller chamber. The angled edgesof the spaced ribsmay be arranged at an angle A (see) that is in the range of 15-20 degrees, for example, 20-25 degrees, such as 23.5 degrees. This example structure of the combing protrusionsmay allow for increased strength and reduced frictional loses since less points may contact the leading roller. Other shapes and configurations for the combing protrusions are also within the scope of the present disclosure.

As shown in, the combing protrusionsmay be disposed at a height H above the bottom contacting surfaceof the leading rollerand on a side or lower half of the leading roller. The placement of the combing protrusionsmay help to prevent the combing protrusionsfrom contacting a carpet, thereby reducing drag on the surface cleaning headand reducing the likelihood of the combing protrusionsdamaging the carpet. This arrangement also allows the combing protrusionsto be exposed to the inter-roller vacuum passageway, thereby enhancing the removal of debris from the leading rollerby the combing protrusions. The combing protrusionmay also substantially prevent air from flowing through the combing protrusionsto the inside upper portion (e.g., upper half) of the leading roller. In other embodiments, a space may be formed between the outer surface of the leading rollerand the back supportsuch that air flows downward through the combing protrusionsto force debris into the air flow through the inter-roller vacuum passageway.

As shown in, an embodiment of the surface cleaning headoptionally includes an electrostatic discharge element (ESD). The ESDmay reduce and/or prevent the buildup of electrostatic charge on the surface cleaning head. The ESDmay include any known device for discharging electrostatic charge. According to one embodiment, the ESDmay include Barnet fibers woven between the openings in the back of the leading roller chamber. The Barnet fibers may be arranged in close proximity to the combing protrusionsand/or leading rollerfor discharging. For example, the ESDmay be connected to a printed circuit board assembly (PCBA) that dumps charge out to the neutral AC line.

In some embodiments, the housingmay further include a bumperforming a top part of the front sideof the housing, as shown in. The bumpermay reduce potential damage to either the surface cleaning headand/or other objects in the environment. A front portion of the leading rolleris exposed at the front sideof the housing, and the bumpermay extend around at least a top of the leading roller. In the example embodiment, the bumperincludes a lateral portionextending laterally along the front sideof the housingand side portions,extending downwardly along left and right sides of the front sideof the housing. The side portions,may extend to a point at or below the second rotation axis RAof the leading roller.

The bumpermay optionally define one or more front edge vacuum passageways,providing at least a portion of the air flow path. As shown in, the bumpermay therefore generally form a seal with a vertical surface(e.g., wall or the like) to improve front edge cleaning. The front edge vacuum passageways,may allow for increased airspeed of the air being sucked into the surface cleaning head, thereby enhancing front edge cleaning. The bumpermay also include one or more lateral air passageways disposed in the lateral portion, which also allow for increased airflow along the front side.

The bumpermay also include one or more compression elements,(e.g., ribs) disposed on the lateral edge/section. The compression elements,allow for increased resiliency and cushioning of the bumper. When the bumperis pushed against the vertical surface(), the compression elements,contact the surfacefirst and push the bumperlocally farther back than the rest of the bumper, thereby forming a gap on either side of the compression elements,. The gaps on either side of the compression elements,form air paths allowing air to be drawn down in front of the leading roller, which may disturb dust and debris so that it can be directed into the air flow path toward the suction conduit.

The bumpermay be formed as one piece with the housingor may be formed as a separate piece secured within a groove and/or notchformed between two or more pieces (e.g., an upper and lower portion,) of the housing, as shown in. The groove and/or notchmay facilitate assembly of the housingand the bumper(e.g., between a headlight portionand main portionof the housing).

In some embodiments, the surface cleaning headmay further include one or more floor sealing strips,and side edge vacuum passagewayson an underside of the housing, as shown in. The floor sealing strip(s),may include one or more sections extending outwardly from the housingand having a length sufficient to at least partially contact the surfaceto be cleaned. The floor seals strip(s),may include soft bristles, fabric material, rubber material, or other material capable of contacting the surface being cleaned to substantially prevent air flow into the openingof the suction conduitfrom the rear side. The sealing strips,may also include a combination of elements or materials, such as bristles with a rubber strip extending along the strip between the bristles (e.g., with the bristles being longer than the rubber strip).

In the example embodiment, a lateral floor sealing stripextends along a rear lateral portion (e.g., behind the openingof the suction conduit) and side sealing stripsextend partially along the left and right sides,. The side sealing stripsextend, for example, along a substantial portion of the openingof the suction conduitand are spaced from the leading rollerto define one or more side edge vacuum passagewaysextending back towards the openingof the suction conduit. Because the leading rolleritself forms a seal with the surfacebeing cleaned, additional sealing strips are unnecessary along the front side. Although separate strips,are shown, one continuous sealing strip may be used. The floor sealing strips,may enhance sealing between the surface cleaning headand the floor, thereby enhancing the vacuum efficiency.

The side edge vacuum passagewaysmay enhance the side edge cleaning efficiency of the surface cleaning head. Side edge vacuum passagewaysdraw in air from the frontand the corner/sides,towards the suction conduit, thereby enhancing edge cleaning as well as front cleaning. At least one of the side edge vacuum passagewaysmay also direct air into the inter-roller air passagewaybetween the leading rollerand the brush rollto facilitate removal of debris from the leading roller. As such, the side edge vacuum passagewaysand the inter-roller air passagewaytogether provide at least a portion of the primary air flow path (e.g., as indicated by arrows) into the suction conduit.

The side edge vacuum passagewaysmay be arranged at an approximately 45 degree angle with respect the longitudinal axis of the housing. In other embodiments, the angle of the side edge vacuum passagewaysmay be within 30 to 60 degrees with respect the longitudinal axis of the housing. Although the side edge passageways are shown as angled straight passageways, other shapes and configurations (e.g., S shaped or curved) are also possible and within the scope of the present disclosure.

Referring to, a combing unitused for cleaning a cleaning rollerin a cleaning apparatus is described in greater detail. The cleaning rollermay be rotatably mounted in a housing, such as the surface cleaning head housing described above, with the combing unitengaging the cleaning roller. The combing unitincludes a series of spaced combing protrusions or teethextending from a back supportand extending partially into the cleaning roller. Although the illustrated embodiment shows the combing unitwith teethextending from a single back support, the combing unitmay also include teeth extending from multiple back supports.

The combing unitmay extend along a substantial portion of a length of the cleaning roller(i.e., more than half) such that the combing teethremove debris from a substantial portion of the cleaning surface of the cleaning roller. In an embodiment, the combing teethmay engage the cleaning surface of the cleaning rolleralong, for example, greater than 90% of a length of the cleaning surface of the cleaning roller. The combing unitworks particularly well with cleaning rollers that are designed to move hair and other similar debris away from a center of the roller.

The combing teethhave angled leading edgesthat are not aligned with a rotation centerof the cleaning roller. The angled leading edgesare the edges that an incoming portion of the rotating cleaning rollerhits first and are directed toward or into a direction of rotation (i.e., into arrow) of the cleaning roller. More specifically, the leading edgeof a combing toothforms an acute angle α relative to a lineextending from an intersection pointwhere the leading edgeintersects with an outer surface of the cleaning rollerto the rotation center. In some embodiments, the angle α is in a range of 5° to 50° and more specifically in a range of 20° to 30° and even more specifically about ° 24 to 25°.

In some embodiments, the combing teethare positioned as close as possible to the bottom contact pointof the cleaning rollerbut high enough to prevent being caught on a surface being cleaned (e.g., a carpet). The combing teeth, for example, may be positioned just above the lowest structure on the housing of a cleaning apparatus. Positioning the combing teethcloser to the bottom contact pointof the cleaning rollerallows debris to be intercepted and removed as soon as possible, thereby improving debris removal.

In another embodiment, shown in, the combing unitmay have other orientations and positions relative to the cleaning roller(e.g., above the rotation center). In a robotic vacuum cleaner, for example, the combing unitmay be positioned higher to prevent the combing teethfrom interfering with the debris being deposited into a dust bin.

The combing teethmay extend into the cleaning rollerto a depth in a range of 0% to 50% of the cleaning roller radius for a soft roller and 0% to 30% of the cleaning roller radius for a tufted brush roll. In one embodiment, the cleaning rolleris a soft roller (e.g., nylon bristles with a diameter less than or equal to 0.15 mm and a length greater than 3 mm) and the combing teethextend into the soft cleaning rollerin a range of 15% to 35%. The combing protrusionsmay be positioned to provide a root gap or spacing between the back supportand the outer surface of the cleaning rollersuch that air may flow between the cleaning rollerand the back supportand through the roots of the combing teeth. The air flow through the roots of the combing teethmay help to dislodge debris that has been removed from the cleaning rollerand to direct the debris into an air flow passageway toward a suction conduit of a cleaning apparatus. The root gap may have a width RG in a range of 1 to 3 mm and more specifically a range of 2 to 3 mm. The root gap RG may extend across an entire length of the combing unit, or a root gap RG may be formed only in one or more sections along the length of the combing unitto form air channels only at those sections. In other embodiments, the back supportof the combing unitmay contact the outer surface of the cleaning rollerto provide sealing and force air to flow under the cleaning roller.

In the illustrated embodiment (), the combing teethhave a triangular-shaped “tooth” profile with a wider base or roothaving a root width Wand a tiphaving a diameter D. In general, the base or rootmay be wide enough to prevent the toothfrom bending upward when contacted by the rotating cleaning rollerand the tipmay be sharp enough to catch the debris. In some embodiments, the tipmay be rounded with a diameter in the range of less than 3 mm and more specifically in the range of 1 to 2 mm and even more specifically about 1.6 mm. The root width Wmay be in a range of 5 to 6 mm.

In another embodiment, shown in, combing teeth′ have a curved profile with curved leading edges′ forming a concave curve. In this embodiment, a lineextending from the curved leading edge′ at the tipforms an angle α with the lineextending from the intersection pointto the rotation center. The combing teeth′ with curved edges may be positioned and spaced similar to the teethwith straight leading edgesas described and shown herein.

In some embodiments, the combing unitincludes combing teethspaced 4 to 16 teeth per inch and more specifically 7 to 9 teeth per inch. The combing teethmay be made of plastic or metal and may have a thickness that provides a desired rigidity to prevent bending when engaged with the rotating cleaning roller. In some embodiments, the combing teethmay have a thickness in a range of 0.5 to 2 mm depending upon the material. In one example, the combing teethare made of plastic and have a thickness of 0.8 mm, a spacing S of about 2.4 mm, and a center-to-center spacing Sc of about 3.3 mm.