Surface maintenance machine

A surface maintenance machine comprising two front wheels, at least one rear wheel, a motive source for providing motive force to at least one front wheel to drive the machine on a surface. Embodiments also include an operator platform allowing an operator to stand thereon extending at least partly around the rear wheel, for supporting an operator in a standing position with the operator's feet on either side of the rear wheel.

BACKGROUND

Surface maintenance machines for relatively large floor areas, for example, of commercial, industrial, public or institutional spaces, are typically integrated with an operator-driven vehicle. These machines can be a floor scrubbing machine or a floor sweeping machine. Other machines, such as polishing, burnishing or outdoor litter collecting machines can also perform other surface maintenance operations such as cleaning (e.g., sweeping, scrubbing, etc.) polishing, burnishing, buffing, stripping and the like on surfaces such as floors, hallways, etc. of buildings, roads, pavements, sidewalks and the like.

Some such surface maintenance machines are commercially available “micro” rider machines, allowing an operator to stand on a platform. Some of these machines have a centrally located front wheel and two rear wheels, with the operator platform inset between the rear wheels. In such machines, a common way to steer and propel a wheel (typically the centrally located front wheel) is by using a wheel motor rotatable by means of a steering linkage. In such machines, the location of the center of gravity should be accounted for to provide stability during normal vehicle operation (e.g., braking during turning).

Moreover, known mechanisms to steer and propel three-wheeled machines, such as using independently driven wheels (e.g., differential steering), can often lead to higher complexity. Prior three wheeled machines with two front wheels and one rear wheel have used steerable rear wheels which may lead to rear swing, which may cause portions of the vehicle to move in a direction opposite to the direction of turn. Rear swing may be undesirable when maneuvering next to objects (walls, curbs, buildings, people, etc.). Another known mechanism for three-wheeled vehicles includes a steerable single front wheel and two rear wheels propelled by a transaxle. This mechanism does not allow for a zero turn (e.g., a turn of zero turning radius). Other ways of steering a three-wheeled machine with two front wheels and a single rear wheel machine include providing a steering linkage connecting the two front wheels. As the steering linkage does permit sufficient steering rotation, such a mechanism would not permit a zero turn.

SUMMARY

In one aspect, this disclosure is directed to a surface maintenance machine comprising a maintenance head assembly with one or more surface maintenance tools for performing a surface maintenance operation. The machine comprises two front wheels, at least one of which is steerable. The two front wheels can be positioned to the front of a transverse centerline of the machine when the machine is moving in a forward direction. The machine further comprises at least one rear wheel positioned to the rear of the transverse centerline. The rear wheel can be interior to the front wheels. The machine may include a motive source for providing motive force to at least one front wheel to drive the machine on a surface.

In another aspect, the surface maintenance machine comprises two front wheels positioned to the front of a transverse centerline of the machine when the machine is moving in a forward direction and a rear wheel positioned to the rear of the transverse centerline. The rear wheel can be positioned generally to the center of the machine. The machine further comprises an operator platform configured for allowing an operator (e.g., adult operator) to stand thereon. The operator platform can be positioned to the rear of the transverse centerline of the machine. The operator platform can be forward and rearward of the rotational axis of the rear wheel. The operator platform can extend at least partly around the rear wheel and laterally outwardly from the sides of the rear wheel for supporting an operator in a standing position with the operator's feet on either side of the rear wheel.

In yet another aspect, a longitudinal centerline of the machine may extend through the rear wheel at a lateral center point of the rear wheel and the front wheels can be positioned on opposite sides of the longitudinal centerline, such that the first and second front wheels and the rear wheel form a triangle. Further, a center of gravity of the machine can be positioned in the front one-third of the machine and projected to fall within the triangle formed by the first and second front wheel and the rear wheel when the operator is not standing on the platform, such that the position of the center of gravity remains generally within the triangle formed by the first and second front wheels and the rear wheel when the operator is standing on the operator platform and the machine is being operated normally.

DETAILED DESCRIPTION

FIG. 1Ais a perspective view of an exemplary surface maintenance machine100.FIG. 1Billustrates the surface maintenance machine100with some body panels removed for clarity. In the illustrated embodiment shown inFIG. 1B, the surface maintenance machine100is s a ride-on machine100. The surface maintenance machine100can perform maintenance tasks such as sweeping, scrubbing, polishing (burnishing) a surface. The surface can be a floor surface, pavement, road surface and the like. Embodiments of the surface maintenance machine100include components that are supported on a mobile body102. As best seen inFIG. 1B, the mobile body102comprises a frame104supported on wheels for travel over a surface, on which a surface maintenance operation is to be performed. The mobile body102may include operator controls (not shown) and a steering control such as a steering wheel108such that an operator109can turn the steering wheel108and control the speed of the machine100without having to remove the operator's hands from the steering wheel108using means well-known in the art. The machine can perform maintenance on a maintenance path which can have an area corresponding to an envelope defined by the front surface112, back surface114and two lateral surfaces116and118of the machine100as the machine travels on a surface120.

The surface maintenance machine100can be powered by an on-board power source such as one or more batteries or an internal combustion engine (not shown). The power source can be proximate the front of the surface maintenance machine100, or it may instead be located elsewhere, such as within the interior of the surface maintenance machine100, supported within the frame104, and/or proximate the rear of the surface maintenance machine100. Alternatively, the surface maintenance machine100can be powered by an external electrical source (e.g., a power generator) via an electrical outlet or a fuel cell. The interior of the surface maintenance machine100can include electrical connections (not shown) for transmission and control of various components.

While not shown in detail inFIG. 1B, the surface maintenance machine100includes a maintenance head assembly400. The maintenance head assembly400houses one or more surface maintenance tools such as scrub brushes, sweeping brushes, and polishing, stripping or burnishing pads, and tools for extracting (e.g., dry or wet vacuum tools). For example, the maintenance head is a cleaning head comprising one or more cleaning tools (e.g., sweeping or scrubbing brushes). Alternatively, the maintenance head is a treatment head comprising one or more treatment tools (e.g., polishing, stripping or buffing pads). Many different types of surface maintenance tools are used to perform one or more maintenance operations on the surface120. The maintenance operation can be a dry operation or a wet operation. Such maintenance tools include sweeping, scrubbing brushes, wet scrubbing pads, polishing/burnishing and/or buffing pads. Additionally, one or more side brushes for performing sweeping, dry or wet vacuuming, extracting, scrubbing or other operations can be provided. The maintenance head assembly400can extend toward a surface on which a maintenance operation is to be performed. For example, the maintenance head assembly400can be attached to the base of the surface maintenance machine100such that the head can be lowered to an operating position and raised to a traveling position. The maintenance head assembly400is connected to the surface maintenance machine100using any known mechanism, such as a suspension and lift mechanism such as those illustrated in U.S. Pat. No. 8,584,294 assigned to Tennant Company of Minneapolis, Minn., the disclosure of each of which is hereby incorporated by reference in its entirety.

In some embodiments, the interior of the surface maintenance machine100can include a vacuum system (not shown) for removal of debris from the surface. In such embodiments, the interior can include a fluid source tank (not shown) and a fluid recovery tank (not shown). The fluid source tank can include a fluid source such as a cleaner or sanitizing fluid that can be applied to the surface120during treating operations. The fluid recovery tank holds recovered fluid source that has been applied to the surface120and soiled. The interior of the surface maintenance machine100can include passageways (not shown) for passage of debris and dirty liquid. In some such cases, the vacuum system can be fluidly coupled to the recovery tank for drawing dirt, debris or soiled liquid from the surface. The vacuum system may comprise a vacuum-assisted squeegee (to be described with respect toFIGS. 8-18) mounted to extend from a lower rearward portion132of machine100. Fluid, for example, clean liquid, which may be mixed with a detergent, can be dispensed from the scrubbing fluid tank to the floor beneath machine100, in proximity to the scrubbing brushes, and soiled scrubbing fluid is drawn by the squeegee centrally, after which it is suctioned via a recovery hose into the recovery tank. Machine100can also include a feedback control system to operate these and other elements of machine100, according to apparatus and methods which are known to those skilled in the art.

In alternative embodiments, the surface maintenance machines100may be combination sweeper and scrubber machines100. In such embodiments, in addition to the elements describe above, the machines100may either be an air sweeper-scrubber or a mechanical sweeper-scrubber. Such machines100can also include sweeping brushes (e.g., rotary broom) extending toward a surface (e.g., from the underside of the machine100), with the sweeping brushes designed to direct dirt and debris into a hopper. In the cases of an air sweeper-scrubber, the machine100can also include a vacuum system for suctioning dirt and debris from the surface120. In still other embodiments, the machine100may be a sweeper. In such embodiments, the machine100may include the elements as described above for a sweeper and scrubber machine100, but would not include the scrubbing elements such as scrubbers, squeegees and fluid storage tanks (for detergent, recovered fluid and clean liquid).

In use, an operator may ride the machine100in a standing position and stand on an operator platform190. The operator platform190can optionally include one or more foot pedals122,124for engaging with maintenance tools406extending from below the machine100, as will be described further below. Continuing with the illustrated embodiment ofFIG. 1B, advantageously, the machine100includes an operator console126provided on the machine100body. The operator console126can include controls for steering, propelling, and controlling various operations of the machine100. For instance, the operator console126can include a steering control such as a steering wheel108such that an operator standing on the operating platform can grasp and turn the steering wheel108to turn the machine100. Further, the operator console126can include speed controls (e.g., such as a knob, not shown) that can control the speed of the machine100without having to remove the operator's hands from the steering wheel108using means well-known in the art. As is apparent from the foregoing disclosure, the operator console126can be approximately at the waist-level of an adult operator standing on the operating platform. Such embodiments allow a compact vehicle design while providing easy to use controls to control the operation of the machine100.

Continuing withFIG. 1B, the surface maintenance machine100according to some embodiments can have an overall width139of less than about three feet. For example, the machine100can have an overall width139of less than about 28 inches. As used herein, the term “width” refers to the distance between lateral surfaces116,118(e.g., perpendicular to the longitudinal centerline and/or the transverse centerline158) of the machine100. The lateral confines of the machine100in such cases are within about 28 inches. In such cases, the machine100has a maintenance path corresponding to an envelope of the surface in contact with the maintenance head assembly400during a surface maintenance operation. The envelope as used herein can be the area defined by the front surface112, back surface114and two lateral surfaces116and118of the machine100. The maintenance path can have a width (e.g., distance between lateral surfaces116and118) of between about 20 inches and about 24 inches. Such machines100are sometimes referred to as “micro-riders” because of their compact sizes. While an exemplary micro-rider machine is illustrated, the embodiments disclosed herein can apply similarly to machines of any sizes and configuration.

With continued reference toFIG. 1B, in certain embodiments, the machine100comprises three wheels. In the illustrated embodiment, the machine100comprises a steerable front wheel140, and a non-steerable front wheel142. As shown herein, the steerable front wheel140and non-steerable front wheel142are positioned toward a lower front portion144to the front of a transverse centerline146of the machine100when the machine100is moving in a forward direction148. As illustrated herein, the transverse centerline corresponds to a line positioned about one-half of the distance182between the front wheels140,142and rear wheel150. Also illustrated inFIG. 1Bis a rear wheel150positioned near the lower rearward portion132to the rear of the transverse centerline146of the machine100when the machine100is moving in a forward direction148. In some cases, rear wheel150comprises a unitary wheel (e.g., one-piece design). For example, in some cases, there may be no other wheels to the rear of the transverse centerline146except for a single rear wheel150. While the rear wheel150is shown as being centered on the longitudinal centerline154of the machine, small offsets from the central location are still contemplated by the illustrated embodiments, and the rear wheel150may not have equal portions extending on opposite sides of the longitudinal centerline154.

In the embodiments illustrated herein, the front wheel140is steered, while the non-steerable front wheel142trails along and turns as the machine100is turned. Alternatively, both front wheels140,142can be steered. In embodiments disclosed herein, at least one of the front wheels140,142is steered, while the rear wheel150may or may not be steered. While the following description is described relative to steering the front wheel140, it should be noted that both front wheels140,142, and rear wheels150can be steered in a manner similar to the operation described relative to front wheel140below.

The machine100comprises a steering assembly having a steering wheel108coupled to (e.g., via a steering column and rack and pinion steering mechanism, or other such steering mechanisms known in the art) the steerable front wheel140. By turning the steering wheel108, the front wheel140can be turned to turn the machine100around a corner. The front wheel140can be turned by any angle to complete a turn having a desired angle (e.g., less than or equal to 90 degrees), as will be explained further with respect toFIG. 3. Such embodiments can be beneficial in allowing a greater degree of freedom for the steerable-front wheel140, thereby permitting the machine100to be used for maintaining surfaces in narrow spaces (e.g., hallways or aisles with width under about three feet, enter or leave doorways having a width of about 28 inches, perform a zero turn in an aisle of width about 60 inches and the like).

Referring now toFIG. 2, the machine100can include a motive source152for providing motive force to the steerable front wheel140to drive the machine100on a surface120. The motive source152can be positioned proximal to and coupled to (e.g., directly or via a transmission system) the front wheels140,142. As such, the illustrated embodiments represent a front wheel140drive and a front steered vehicle. The rear wheel150in such cases can be neither steered nor propelled, thereby allowing for the rear wheel150to remain substantially stationary when the machine100is turned by an operator. The rear wheel150in some embodiments can be a non-marking wheel (e.g., made of a material that is resilient relative to the frame104of the machine100) to reduce wheel marks on the surface120being maintained. For example, as shown inFIG. 2, the machine100can include a motor coupled the steerable front wheel140to drive the front wheel140. In such cases, the non-steerable front wheel142may not be propelled by the motive source152. For example, the non-steerable front wheel142can be a caster and remain non-steered and non-driven during normal operation of the machine100and merely turn or rotate to facilitate moving the machine100. As will be further explained below, embodiments such as those illustrated inFIG. 2can offer improved stability and reduce “rear swing” over other three-wheeled drive and steering systems of machines100known in the art, especially when the machine100is being turned around a sharp turn (e.g., 90 degrees or more) with respect to the forward direction148of the machine100.

Alternatively, the motive source152can propel the rear wheel150. In such cases, the rear wheel150may or may not be steerable, while one or more of the front wheels140,142can be steerable. Any configuration of steering and propelling of the wheels are contemplated, and the embodiments described herein are not limited to the illustrated embodiment shown inFIG. 2. For example, the two front wheels140,142can each steerable by a steering mechanism (e.g., a single steering mechanism steering two front wheels). Similarly, both front wheels140,142can be propelled by the motive source152for providing motive force to the front wheels. Alternatively, at least one of the front wheels140,142are steerable by a steering mechanism, and the rear wheel150is non-steerable, but can be propelled by a motive source for providing motive force to the rear wheel150.

During use, an operator may have to turn the machine100to perform a surface120maintenance operation, or to travel to a different surface. For example, an operator may turn the machine100less than or equal to about 180 degrees (e.g., a left turn, a right turn or a U-turn) from the forward direction148in a narrow aisle. In such cases, to improve the stability of the machine100and also to reduce rear swing, in the embodiments described herein, the rear wheel150is neither driven by the motive source152, nor steered. The machine therefore pivots about a stationary pivot point220when turned. When an operator turns the machine100by a desired angle (e.g., 90 degrees), the machine100turns about the stationary pivot point220by the desired angle. As the rear wheel150is not driven or steered, its chances of traversing a path having a radius of curvature different from (e.g., wider than) the radius of curvature of the turn are reduced. Such embodiments reduce rear swing and any damage due to collision of the rear of the machine100with any obstruction to the rear of the transverse centerline146of the machine100(e.g., walls, etc.) as the machine100is cleaning in the proximity of an obstruction, such as along a wall or around a corner.

Continuing with the above, the stationary pivot point is at the intersection of a longitudinal centerline154of the machine and a rotational axis151of the rear wheel150. In some cases, the rear wheel150can be an idler wheel. In such cases, the rotational axis151of the rear wheel150is parallel to the transverse centerline146of the machine when the machine turns. Alternatively, in some embodiments, the rear wheel150can pivot to a limited extent. In such cases, the rotational axis151of the rear wheel150is passively pivotable relative to the transverse centerline146of the machine. In such cases, the rear wheel150is non-steerable and is not propelled, but may pivot to a limited extent similar to a caster. Still further, the rear wheel150can be actively steered (e.g., by the steering mechanism and/or a transaxle) and/or propelled (e.g., by the motive source152). In examples where the rear wheel150is actively steered, the rotational axis151is actively pivotable with respect to the transverse centerline146of the machine by a steering mechanism and/or a transaxle.

With continued reference toFIG. 2, the rear wheel150is generally centered about a longitudinal centerline154of the machine100such that the rear wheel150extends on two opposite sides of the longitudinal centerline154. As used herein “generally centered” includes small offsets of the rear wheel150relative to the longitudinal centerline such that portions of the rear wheel150that extend on either side of the longitudinal centerline154may not be exactly equal. As illustrated herein, the longitudinal centerline154can correspond to a line positioned about one-half of the distance184between the front wheels140,142. The steerable and non-steerable front wheels140,142may be positioned symmetrically or asymmetrically on either side of the longitudinal centerline154of the machine100. In such cases, as best seen inFIG. 3, the front and rear wheels140,142,150are arranged in a triangular orientation. When viewed from the bottom, each of the front and rear wheels140,142,150form a vertex of the triangle156, with the sides158,160of the triangle156tapering from the front of the machine100to the rear. As will be described further below, such embodiments with two front wheels140,142and a single rear wheel150can offer less sensitivity to center of gravity position over conventional three-wheeled surface maintenance machines (e.g., such as conventional machines having a single front wheel and two rear wheels). In such embodiments, there may be no other wheel other than the rear wheel150positioned to the rear of the transverse centerline of the machine that is inline with the rotational axis151of the rear wheel. Accordingly, the rear wheel150is centrally located such that it is symmetrically positioned on the longitudinal centerline154of the machine. In such a configuration, the machine100has three contact points with the surface120, each contact point corresponding to each of the front wheels140,142and the rear wheel150. The contact points define a contact plane such that no other wheels except the three wheels140,142, and150contact the surface120at the contact plane.

As referred to previously, the front wheel140is coupled to a steering wheel108to turn the machine100by a desired angle, while the rear wheel150remains stationary while turning. For instance, as the machine100is turned, it may pivot about the center of the stationary rear wheel150. As shown inFIG. 3, the steerable front wheel140(and the motive source152coupled thereto) can be offset with respect to the longitudinal centerline154of the machine100. One skilled in the art would recognize that as a result of this orientation, the front wheel140turns by a turning angle with respect to the longitudinal centerline154wherein the turning angle may be greater than the desired angle by which the machine100is to be turned. For example, in the illustrated embodiment, the front wheel140is turned by a turning angle greater than 90 degrees (e.g., between about 100 degrees and about 110 degrees) with respect to the longitudinal centerline154of the machine100to turn the machine100away from the longitudinal centerline in the direction181shown inFIG. 3. Moreover, if the front wheels140,142are to be spaced further apart than by the distance184shown inFIG. 3, the turning angle of the steering wheel108increases further from the exemplary angles (e.g., greater than about 110 degrees) described herein in order to turn the machine100away from the longitudinal centerline (e.g., along arrow181) by an angle of about 90 degrees. Similarly, the steering assembly is configured for steering the front wheel by an angle less 90 degrees with respect to the longitudinal centerline of the machine when turning the machine toward the longitudinal centerline (e.g., along the direction183) by an angle of about 90 degrees.

With continued reference toFIG. 3, the triangular orientation of the front wheels140,142and the rear wheel150permits a center of gravity162of the machine100to be suitably located. For instance, a projection of the center of gravity162, in the top plan view ofFIG. 3is shown as being positioned substantially toward the front of the transverse centerline146and within the triangle156formed by the front and rear wheels140,142,150. As is apparent to one of ordinary skill in the art, when the projected position of the center of gravity162of the machine100lies within the triangular orientation of the front and rear wheels140,142,150, the machine100remains in stable equilibrium, and is undue instabilities during use of the machine100(e.g., braking during turning, etc.) may be reduced. Such undesirable effects may include excessive lateral acceleration due to centrifugal forces directed radially outward about the center of curvature of the turn that throws the operator outwardly while turning. In some exemplary embodiments, the machine100can be front-loaded to position its center of gravity162to the front of the transverse centerline146and within the triangle156. For example, heavier components of the machine100(e.g., scrub head, battery or other power source, motive source152such as motor) can be positioned to the front of the transverse centerline146. Such embodiments have a weight distribution wherein more of the machine100's weight is toward its front when an operator is not standing on the operator platform190and/or when solution tanks positioned to the front of the transverse centerline146comprising clean or dirty liquids are full, thereby moving the center of gravity162to the front of the transverse centerline146of the machine100. For instance, in some such cases, the center of gravity can be within the front one-third of the machine100(e.g., one-third of the distance182shown inFIG. 3) and projected to fall within the triangle156formed by the first and second front wheels140,142, and the rear wheel150when the operator is not standing on the platform190. In such cases, the position of the center of gravity can be configured to remain generally within the triangle156formed by the first and second front wheels140,142and the rear wheel150when the operator is standing on the operator platform and the machine is being operated normally. As used herein, “normal operation” can refer to any of the following: being driven on a floor surface, braked, turned, braked during a turn, when solution tanks are empty, when the operator has at least one foot on the operator platform, performing one or more maintenance operations on the surface and the like. Such embodiments can also reduce the chances of the machine100(e.g., to the rear of the transverse centerline146) having weight imbalances when an operator steps on or off from the operator platform190, and when the operator is standing on the platform190. For instance, embodiments such as those disclosed herein have reduced instabilities (e.g., tipping, one of the wheels losing contact with the surface, and the like) when the operator has one foot on the operator platform190. Additionally, the machine reduces instabilities (e.g., tipping, one of the wheels losing contact with the surface, and the like) when the operator has both their feet on the operator platform190, and when the machine turns, brakes during a turn or travels on an inclined surface.

When the weight of the machine100or the operator shifts (e.g., braking during turning or traveling on an inclined surface, etc.) by allowing the center of gravity162of the machine100to remain lower to the ground and to the front of the machine100(e.g., at position162′ shown inFIG. 4A), turning moments (e.g., that could result in instabilities due to lateral forces overcoming gravitational forces acting on the center of gravity of the machine100) are reduced as is well-known to one of ordinary skill in the art. For example, the projected position of the center of the gravity162is positioned in close proximity to the surface120such that the center of the gravity162is no greater than the lower one-half, and more preferably one-third of the machine height when an operator is standing on the operator platform190. In some such cases, the machine is stable when the operator is turning the machine (e.g., a zero turn) and/or braking while turning. In some such cases, and referring toFIGS. 1B and 4A, components of the machine100can also be arranged such that the a lower portion164of the machine100below a major center plane166of the machine100is heavier relative to an upper portion168of the machine100to above the major plane166of the machine100when an operator is standing on the operator platform190. Such embodiments lower the center of gravity162so that its projected position is further toward the surface120, and reduce the machine100and/or the operator from experiencing dynamic instabilities during normal use of the machine100which can involve operations such as braking during turning, performing a zero turn, or other similar operations. During such operations, even if the weight of the machine100or the operator's position shifts, the projected position of the center of gravity162lies proximal to the surface120and within the lateral confines (e.g., sides158,160) of the triangular configuration of the front and rear wheels140,142,150. Such embodiments reduce the potential for the machine100to become unstable during routine use of the machine100.

With continued reference toFIG. 3and referring now toFIG. 4A, the stability of the machine during turning (e.g., zero turns) or braking during turning can be illustrated by the geometric orientation of the front and rear wheels. As seen inFIG. 3, the rear wheel150is cylindrical in shape and has a first lateral side170and a second lateral side172. The front wheels140,142are each oriented such that the sides158,160from each of the front wheels140,142abut the lateral sides170,172of the rear wheel150. In such embodiments, the projected position of the center of gravity162is generally contained within the triangular area between the front and rear wheels140,142,150due to front loading the machine100. As a result, force and moment imbalances are reduced, thereby allowing the operator to ride, turn, brake during turn or travel over an inclined surface with increased safety.

Continuing with the above, the center of gravity162is positioned substantially toward the front of the transverse centerline146and projected to fall within the triangle156formed by the front wheels140,142and the rear wheel150when the operator is standing on the operator platform190and performs at least one of turning, braking during a turn, or travel over an inclined surface. As shown by the schematic ofFIG. 4A, if for instance, an operator turns the machine and/or brakes during a turn, in an exemplary embodiment, the resulting braking force vector indicated by arrow162′ is toward one of the front wheels when turning.

In conventional three-wheeled machines, a single front wheel310and two rear wheels320,330form a triangle366, where the conventional three-wheeled machine has a longitudinal centerline354and a transverse centerline346as shown inFIG. 4B. In this embodiment, when an operator brakes during a turn, the location of the center of gravity362is inherently connected to the stable operation of the machine. For instance, if an operator turns the machine and/or brakes during a turn, the resulting braking force vector indicated by arrow362′ is toward the line between the front wheel and one of the rear wheels when turning and outside the triangle366. In contrast, in embodiments of the surface maintenance machine with two front wheels and a single rear wheel illustrated schematically byFIG. 4A, the resulting braking force vector162′ remains generally within the triangle156, and as result, has relatively improved stability while braking during a turn, ramp climbing or during a zero turn. During these operations of the machine, the machine generally resists various accelerations and decelerations better because of front wheels140,142being wide set and have a substantially broad envelope to the front of the transverse centerline146due to two front wheels140,142and a single rear wheel150. Accordingly, if the machine's normal operations such as turning, braking during a turn remains generally within the triangle156. The machine therefore has generally improved stability and resists a wheel (e.g., a front wheel inner relative to the radius of a turn) losing its contact with surface on which the machine operates due to moments about the center of gravity162.

Referring now toFIG. 5, the surface maintenance machine100comprises an operator platform190to allow an operator to stand thereon. The operator platform190can be positioned to the rear of the transverse centerline146of the machine100. The operator platform190extends around the rear wheel150, and laterally outwardly from the longitudinal centerline154for supporting an operator in a standing position with the operator's legs on either side of the rear wheel150as shown inFIG. 1B. The rear wheel150can be positioned centrally with respect to the platform. In some such cases, the platform190optionally includes a cut-out portion192. The cut-out portion192of the operator platform190receives the rear wheel150. The operator platform190comprises a first side portion193, a second side portion195and a central portion197. The cut-out portion192in such cases is surrounded on opposite lateral sides by the first and second side portions193and195. The first and second side portions193and195are each integrally formed with the central portion197. As seen inFIG. 5, the first and second side portions193,195extend on opposite sides of the rear wheel150. An operator can stand in a standing position such that the first and second side portions193,195each receive an operator's foot. Accordingly, the first and second side portions193,195can have a width sufficient to accommodate an operator's foot,201,203. For example, the width can be between about 5 inches and about 8 inches such that an adult operator can comfortably stand in the first and second side portions193,195so that the operator's foot201,203are on both sides of the rotational axis151(and positioned thereabove). Alternatively, the operator platform190may not have a cut-out portion, and can be positioned above the rear wheel150.

Optionally, in some embodiments wherein the operator platform190has a cut-out portion192, a cover (not shown) can be positioned over the rear wheel150to avoid the operator's foot from inadvertently contacting the rear wheel150. The rear wheel150is approximately at the same height above the surface120as a central rotational axis of the rear wheel150. Such embodiments allow the operator a wider tread surface than is conventionally used in “micro” rider style surface maintenance machine100by having the rear wheel150be positioned centrally, and by having the operator platform190extend around it. In some such cases, the operator platform190is of a width191that approximately equals the width139of the maintenance path137and/or the width136of the machine.

In embodiments illustrated inFIG. 5, during a turn (e.g., a zero turn), the point about which the machine turns (referred to as “center of turn”) can generally be within an envelope of the operator platform when the machine is being turned up to and during a zero turn. Such embodiments allow the operator comfort during a turn and further ensure stability during zero turns.

FIG. 6illustrates a side perspective view of a cross-section taken along the plane6-6illustrated inFIG. 5.FIG. 7illustrates a top view of a rear portion of the machine100. InFIGS. 6 and 7, the forward direction of travel of the machine100is illustrated by the arrow referenced as148. As shown inFIGS. 6 and 7, machine100has at least one rear wheel150. In embodiments where the rear wheel150is rotatable, the rotation is about the rotational axis198. As seen inFIGS. 6 and 7, the operator platform190extends both to the front and the rear of the rotational axis198of the rear wheel150. The central portion197is to the rear of the rotational axis198and the first and second side portions193,195extend to the front and rear of the rotational axis198. In such embodiments, when an operator stands on the operator platform190, the operator's feet201,203can be to the front and rear of the rotational axis198. As is seen inFIGS. 6 and 7, the operator platform190also extends to the front and rear of the entire rear wheel150. The rear wheel150is surrounded by the first and second side portions193,195and the central portion197of the operator platform190. The rear wheel150can thus be positioned, such that the operator platform190extends deeper relative to the diameter of the rear wheel150.

Embodiments of a surface maintenance machine100with a rear operator platform190disclosed herein offer several advantages. The rear standing platform allows the operator to standing in a desired position with a wider tread surface than is conventional. The rear standing platform with a wider tread allows the operator to step on and off the machine100. Components of the machine100according some embodiments are arranged to have the machine100be front loaded and the center of gravity162be lower toward the ground. Such embodiments offer improved stability, and additionally provide for efficient use of space for packaging batteries and cleaning components. Embodiments also provide for a short overall length for the machine100, forward protection for the operator, low step-on height, and easy presentation of controls to the operator. Embodiments of the machine also allows an operator to rapidly decelerate during a turn, thereby providing a safe operation of the machine (e.g., if an operator encounters an obstacle) and results in satisfactory maintenance performance (e.g., by reducing the chances of scrubbing tools from throwing off liquids when turning too fast).

Referring now toFIG. 8, which illustrates a portion of the machine100shown inFIG. 1B, the surface maintenance machine100includes a maintenance head assembly400. The maintenance head assembly400houses one or more maintenance tools406such as scrub brushes, sweeping brushes, and polishing, stripping or burnishing pads, and tools for extracting (e.g., dry or wet vacuum tools) as described previously. The maintenance head assembly400comprises a deck402that houses one or more maintenance tools406(best seen inFIG. 9). The maintenance tool406can be rotatable relative to the remainder of the maintenance head assembly400(such as the deck402), for instance, by a motive source404(e.g., a motor) that can be coupled to the maintenance tool406(e.g., using belts, or other motive force transmission systems, not shown) that apply torque and thereby impart a rotational motion on to the maintenance tools406. The maintenance head assembly400can be attached to the body (e.g., a frame member104) of the surface maintenance machine100such that the maintenance head assembly400can be lowered to an operating position (so as to be in contact with the floor surface120) and raised to a traveling position when the machine100is not performing a maintenance operation. The maintenance head assembly400is connected to the surface maintenance machine100using any known mechanism, such as a lift mechanism and suspension452, as illustrated in U.S. Pat. No. 9,124,544, assigned to the assignee of the present application, Tennant Company of Minneapolis, Minn., the disclosure of which is hereby incorporated by reference.

With continued reference toFIG. 8, the lift mechanism and suspension452allows the maintenance head assembly400to be raised and lowered and allows the maintenance tools406to conform to undulations in the floor. The deck402of the maintenance head assembly400is attached to the frame104of the machine100(not shown inFIG. 8) by a lift mechanism and suspension452assembly that includes a lift arm454, a linear actuator (not shown), and associated coupling structures. Coupling structures include brackets, springs, control arms, and the like for providing controlled pivoting of the linear actuator relative to the deck402so as to remain in contact with the floor surface120(e.g., when traveling over uneven floor surfaces) when performing a maintenance operation, and be raised to the traveling position when the machine100is not performing a maintenance operation.

Components of the lift mechanism and suspension452can be operatively coupled to the operator console126and/or foot pedals122on the operator platform190. For example, the foot pedals122can be mechanically coupled to coupling structures of the lift mechanism and suspension452. Additionally, the foot pedals122can be electrically coupled to a controller in communication with the linear actuator such that when the foot pedals122are pressed by the operator's feet, the controller communicates with the linear actuator to raise or lower the maintenance bead assembly to move it between the operating position and the transport position.

With continued reference toFIG. 8, a squeegee assembly500is provided on the rear of and connected to the maintenance head assembly400. The squeegee assembly500can drag on the surface along the sides of maintenance tool406to keep water on the floor from spreading out sidewise away from the machine100. The squeegee assembly500curves inward to direct the water centrally to the machine100toward the rear thereof. A vacuum system (not shown) is fluidly coupled to the squeegee assembly500so as to collect the water accumulating on the rear of the machine and deposit the collected water into a waste recovery tank (not shown). The maintenance head assembly400can be configured to “float” relative to machine100, thereby keeping the maintenance tool406(e.g., a brush or a pad) in contact with the surface being maintained (e.g., cleaned or treated) even if the surface is somewhat irregular or uneven. Likewise, due to the mechanical connection between the squeegee assembly500and the maintenance head assembly400, the squeegee assembly500can also float relative to machine100to enable the squeegee assembly500to remain in contact with surfaces being maintained, even though they are somewhat irregular or uneven.

The squeegee assembly500includes a frame502, squeegee blades504,506, and a retainer508. Blades may include one or more flexible blades that may be spaced apart or tight against each other. For instance, the illustrated embodiment provides an inner squeegee blade504facing the maintenance head assembly400, and an outer squeegee blade506positioned to the rear of the inner squeegee blade504(e.g., when the machine is moving in a generally forward direction). The inner squeegee blade504generally confronts water on the floor surface120first and directs water toward a central portion of the squeegee blades504,506. Further, the inner squeegee blade504and outer squeegee blade506may be in contact with the floor surface120. In some such cases, the inner squeegee blade504can have vents to draw-in liquids into a plenum formed by the inner squeegee blade504and outer squeegee blade506. The squeegee blades504,506can therefore form a seal with the floor. The vacuum system may apply a vacuum in the plenum between the outer and inner squeegee blades504,506, which, due to the seal formed with the floor surface120, and optionally due to vents on the inner squeegee blade504, facilitates suction of collected water from the center of the squeegee. Squeegee blades504,506can also deflect in a controlled manner to a predetermined extent (for instance, deflection about twice the thickness of the blade) to effectively collect liquids from the floor surface.

The blades can contact the floor surface120and are made from suitable material such as rubber, neoprene, urethane, or the like. The one or more flexible blades may be of the same or of differing thicknesses, have differing levels of flexibility, and may have differing lower extents. Exemplary squeegee assemblies contemplated in the present disclosure include the squeegee assemblies described in U.S. Pat. No. 9,049,975, assigned to the assignee of the present application, the disclosure of which is hereby incorporated by reference. The squeegee assembly500can be of a sufficient weight so as to apply uniform pressure on the squeegee blades504,506substantially around the perimeter of the squeegee assembly500. For instance, the weight of the squeegee assembly500can be configured so as to apply a certain magnitude of downforce on the squeegee blades504,506. Additional mechanical members (e.g., wheels and castors, as will be described further below) can further facilitate uniform application of downforce on the squeegee assembly500.

As described further below, embodiments of the present disclosure permit an interchangeable squeegee assembly500that can be connected to different sizes of maintenance tools406(brushes or pads), while facilitating easy removal for servicing (e.g., replacing or “rotating” squeegee blades504,506due to wear). Further, the squeegee assembly500according to certain embodiments of the present disclosure can also be designed as articulating, so as to effectively direct and collect water from the surface when the machine is being turned (e.g., around a corner in a building).

FIG. 9is a top plan view of the assembly shown inFIG. 8to illustrate the relative position of the squeegee assembly500and the maintenance head assembly400when the machine is traveling in a generally straight path in a direction indicated by the arrow.FIGS. 10 and 11show respectively, a perspective view and a top plan view of the squeegee assembly500ofFIGS. 8 and 9to illustrate the relative position of the squeegee assembly500and the maintenance head assembly400when the machine takes a turn relative to the direction510. As seen inFIGS. 8-11, some embodiments of the present disclosure advantageously provide an articulating mechanism520to permit controlled articulation of the squeegee assembly500when the machine is turned (e.g., a right or a left turn, relative to the travel direction shown inFIG. 8) to direct and collect water that may pool up when the machine is turned.

Referring now toFIG. 8, the articulating mechanism520is attached to coupling structures on the deck402of the maintenance head assembly400. For example, the articulating mechanism520can be connected to brackets522to which the lift arm454of the lift mechanism and suspension452. Of course, the articulating mechanism520can also be connected at other locations on the deck402of the maintenance head assembly400. The connection of the articulating mechanism520can be such that it is easily removable in the event that the squeegee assembly500needs to be replaced for servicing. For instance, the connection of the articulating mechanism520can be to the exterior of the motive source404(e.g., motor) of the maintenance head assembly400, so that an operator may be able to detach the squeegee assembly500without having to disconnect numerous connections such as those of the lift mechanism and suspension452, and the like.

As seen inFIGS. 10 and 11, the articulating mechanism520permits controlled articulation of the squeegee assembly500. As used herein, the term articulation may include both pivotal motion (along arrows524) of the squeegee assembly500relative to the maintenance head assembly400about a pivot axis526, as well as swivel motion (along arrows528) of the squeegee assembly500about the swivel axis530. In some exemplary embodiments, the articulating mechanism520may permit a swivel of about 80 degrees either side of the swivel axis530, thereby a total swivel arc of about 170 degrees. Such embodiments permit effectively collecting water from behind the machine when the machine completes a sharp turn of about 90 degrees. In such cases, as is apparent to one skilled in the art, the swivel axis530of the squeegee assembly500generally coincides with the center of turn of the machine and/or centroid of the maintenance head assembly400.

FIGS. 12 and 13illustrate another embodiment of the maintenance head assembly600. The maintenance head assembly600ofFIGS. 12 and 13are substantially similar to that illustrated inFIGS. 8 and 9, with the exception that the embodiment ofFIGS. 12 and 13is generally oval in shape (as seen from the top plan view ofFIG. 13), with a deck602configured to house a pair of disc-shaped maintenance tools (e.g., brushes or pads), whereas the embodiment ofFIGS. 8 and 9is generally circular in shape (as seen from the top plan view ofFIG. 9). In the view shown inFIGS. 12 and 13, the machine is traveling in a generally straight path, in a direction indicated by the arrow606.FIGS. 14 and 15show respectively, a perspective view and a top plan view of the maintenance head assembly600ofFIGS. 12 and 13to illustrate the relative position of the squeegee assembly500and the maintenance head assembly600when the machine takes a turn. While the articulating mechanism520is described above with respect toFIGS. 8-11, it should be understood that the articulating mechanism520shown inFIGS. 12-15operates in a similar fashion to that shown inFIGS. 8-11.

FIG. 16illustrates an enlarged perspective view of the articulating mechanism520. The articulating mechanism520seen inFIG. 16can be coupled to the maintenance head assembly400shown inFIGS. 8-11or maintenance head assembly600shown inFIGS. 12-15. As seen therein, the articulating mechanism520comprises a swivel mechanism610for controlled swivel of the squeegee assembly500about the swivel axis530and a hinge mechanism630for controlled pivoting of the squeegee assembly500about the pivot axis. The swivel mechanism610comprises at least one curved rail on which two or more rollers616,618are guided. In the illustrated embodiment, two curved rails612,614radially offset from each other. The rails612,614are curved such that they have a center of curvature that coincides with the swivel axis530, and in turn, the center of turn of the machine and/or centroid of the maintenance head assembly400. In the illustrated embodiment, the curvature of the rails612,614corresponds to an arc extending between about 130 degrees and about 180 degrees. Further, the curvature of the rails612,614is generally circular (e.g., as seen from the top view ofFIGS. 9, 5, 7 and 9) such that any two points on the rails612,614are generally equidistant from the center of the curvature of the rails612,614(as is apparent fromFIGS. 12-15). While two rails having a fixed radius corresponding to a circular shape is illustrated, other shapes of the rails612,614(e.g., a non-circular curvature) can be used to customize the articulating mechanism based on the machine architecture. For example, the rails612,614can follow a generally oval shape when viewed from the top so as to conform to the shape of the oval maintenance head assembly shown inFIG. 12-9. Alternatively, a non-uniform shape can also be used for other machine and/or maintenance head assembly architectures.

While the rails612,614are illustrated as being generally tubular in shape, other shapes such as rectangular or square cross-section are contemplated within the scope of the present disclosure. Further, in addition to being radially offset, the rails612,614can be axially offset (e.g., along the swivel axis530) such that one rail is above another rail. Alternatively, the rails612,614may not be radially offset, but may be axially offset such that one rail is above another rail, but both rails have the same radius from their center of curvature. Any orientation of the rails612,614that is adequately rigid and resists structural loads (e.g., flexures) generated due to swiveling of the squeegee assembly500when the machine turns, and supports the weight of the squeegee assembly500can be used. Additionally, while rails are illustrated, it should be noted that track and carriage systems or other mechanical equivalents that permit guided motion of the squeegee assembly500over an arcuate path are contemplated within the scope of the present disclosure.

With continued reference toFIG. 16, the swivel mechanism610comprises a pair of rollers616,618housed in a swivel bracket620that roll against the rails612,614. The rollers616,618and rails612,614can be configured to have minimal friction therebetween such that the rollers616,618freely roll in a guided fashion along the rails612,614. For instance, and referring now to the sectional view ofFIG. 17, the rollers616,618comprise an outer sleeve622made of low-friction materials such as Delrin, nylon, and the like permitting frictionless rolling motion of the outer sleeve622on at least one rail (for instance, the inner rail612). Additionally, the rollers616,618can also roll on the outer rail614. Further, the rollers616,618comprise a metal bushing624housed within the outer sleeve622so that the rollers616,618can maintain structural rigidity and withstand dynamic loads experienced while rolling on the rails. For example, while the outer sleeve622may roll against at least one of the rails612,614when the machine turns, the bushing624may be substantially stationary relative to the outer sleeve622so as to support and balance the articulating motion of the squeegee assembly500and associated loads acting thereon. The outer sleeve622of the rollers616,618can have end caps that engage with at least one of the rails612,614, and to reduce the chances of the rollers616,618separating from the rails612,614. In the illustrated embodiment, the rollers616,618are shaped to resemble spools, although any shape that provides the above-described function is contemplated within the scope of the present disclosure.

Referring back toFIG. 16, the rollers616,618are connected to the swivel bracket620by way of a bolted connection. When connected, the rollers616,618are spaced apart from each other along a circumferential direction by an arc distance. In the illustrated embodiment, the spacing between the two rollers616,618extends an arc of between about 15 degrees and about 30 degrees. Such embodiments provide sufficient resistance to certain forces by spreading out such forces acting on the swivel mechanism610over a larger area. For instance, if the squeegee assembly500abuts against an obstacle and experiences side impact when the squeegee assembly500has swiveled to the position shown inFIGS. 10-11orFIGS. 14-15, the side impact experienced by the squeegee assembly500is spread out over a substantial area of the swivel bracket620, thereby reducing damage to the swivel mechanism610. As is apparent to one skilled in the art, further spacing the rollers616,618apart may provide additional area to distribute impact loads, however, at the expense of reduced swivel path. While the examples illustrated herein permit a swivel of about 80 degrees on either side of the swivel axis530(for a total of about 170 degrees), larger or smaller swivel is contemplated within the scope of the present disclosure. For example, the swivel can be between about 100 degrees and about 270 degrees. Similarly, roller spacing greater than or less than those illustrated (e.g., between about 15 degrees and about 30 degrees) are contemplated within the scope of the present disclosure.

Referring back toFIG. 8, as alluded to before, the rails612,614are connected to the maintenance head assembly400by way of brackets522and a bolted connection.

Advantageously, the brackets522connect to the brackets of the lift mechanism and suspension452which provides a compact connection of the squeegee assembly500to the maintenance head assembly400. The brackets, while illustrated as L-shaped, can be of any shape so as to serve as limit stops for the swivel mechanism610to reduce the chances of the squeegee assembly500traveling too far, and being damaged (e.g., by making contact with wheels140of the machine). In the illustrated embodiment, the brackets are positioned diametrically opposite to each other (e.g., about 180 degrees apart) accommodate a swivel arc of between about 100 degrees about 180 degrees, though of course, the brackets522may be positioned closer or farther apart.

Referring again toFIG. 16, the articulating mechanism520comprises a hinge mechanism630for controlled pivoting of the squeegee assembly500relative to the maintenance head assembly400about one or more pivot axes. The hinge mechanism630facilitates maintaining the squeegee assembly500(e.g., squeegee blades504,506) generally parallel to the floor. The hinge mechanism630permits the squeegee blades504,506(e.g., the outer squeegee blade506) to remain in contact with the floor surface120. The hinge mechanism630is a double-hinge design, permitting pivoting of the squeegee assembly500relative to the maintenance head assembly400about a first pivot axis526, and a second pivot axis632. The first pivot axis526offset vertically above the second pivot axis632. The hinge mechanism630comprises a hinge plate634that engages with the swivel bracket620at one end, and an H-shaped hinge bracket636at the other end. The first pivot axis526passes through the hinge plate634. The hinge bracket, in turn is connected with vertical brackets638by a bolted connection. The second hinge axis passes through the bolted connection between the hinge bracket and the vertical brackets638.

Such a configuration may permit the squeegee to be in contact with the floor surface120in different modes. For instance, the machine may be operated when the squeegee picks up water from floor while the maintenance tool406(e.g., scrub brush) is in contact with the floor surface120and is performing a maintenance operation (e.g., scrubbing). Alternatively, the machine may be operated such that the squeegee picks up water from the floor while the maintenance tool406is not in contact with the floor surface120, for instance, when excess water from a flooding may have to be picked up from the ground. Still further, the squeegee may have to not be in contact with the floor surface120while the maintenance tool406is performing a maintenance operation (e.g., a pre-soak while scrubbing). In such cases, the double hinge design of the hinge mechanism630allows the squeegee assembly500to be raised above or below the maintenance head assembly400, while also permitting the squeegee blades504,506to be parallel to the floor surface120. Such embodiments advantageously offer effective water pick-up which may not be possible with hinge mechanism630that permit pivoting about a single pivot axis. Instead of the illustrated hinge mechanism630, mechanical equivalents, such as a vertically-oriented slot and/or rollers housed within the vertical slot can also be used in alternative embodiments.

FIG. 18illustrates a side view of the squeegee assembly500of the present embodiment. As mentioned above, the embodiment illustrated inFIG. 18can be used interchangeably with the maintenance head assembly400shown inFIGS. 8-11orFIGS. 12-15. The squeegee assembly500comprises a first set of end wheels. In the illustrated embodiment, the squeegee assembly500comprises four end wheels. A first end wheel642is configured to roll on the surface120when the squeegee assembly500articulates (e.g., into the positions shown inFIGS. 10, 11, 14 and 15) when the machine turns. Further, a second end wheel644provided with a rotational axis646perpendicular to the rotational axis648of the first end wheel642. Further, the first end wheel642may swivel about the plane containing the rotational axis646, for instance, relative to the maintenance head assembly as illustrated inFIG. 18. As is apparent to one skilled in the art, the squeegee assembly500comprises a second set of end wheels opposite to the first set of end wheels so that the first and second set of end wheels terminate at the opposite ends of the curved squeegee assembly500. Similar to the first set of end wheels, the second set of end wheels may comprise a third end wheel650configured to roll on the surface120when the squeegee assembly500articulates (e.g., into the positions shown inFIGS. 10, 11, 14 and 15) when the machine turns. Further, a fourth end wheel652provided with a rotational axis perpendicular to the rotational axis of the third end wheel650. While end wheels are illustrated as cylindrical members that can swivel, it should be understood that castors may also be used in lieu of end wheels without loss of functionality. In the illustrated embodiment, end wheel652may act as a bumper when the squeegee assembly encounters lateral impacts due to an obstruction (e.g., a wall), whereas the end wheel644can support the front of the squeegee assembly during transport. Instead of wheels644and/or652, as is apparent to one skilled in the art, other mechanical means that act as bumpers and/or supports (e.g., simple brackets) may be used without loss of functionality.

In addition to the set of end wheels, as is seen fromFIG. 18, the squeegee assembly500includes a caster660positioned centrally between the first and second set of end wheels. As indicated previously, the mass of the squeegee assembly500facilitates applying a predetermined magnitude of downforce on the squeegee blades504,506. The end wheels (e.g., first end wheel and third end wheel650) and caster660can further facilitate uniform application of downforce on the squeegee assembly500.

The caster660and/or end wheels may also facilitate articulating the squeegee assembly500corresponding to the direction of turn of the machine. For instance, when the machine turns in a certain predefined direction (e.g., a 90-degree right turn relative to its forward direction of motion), as a result of the frictional contact of the squeegee blades504,506on the floor surface120and the squeegee assembly500may articulate to follow the direction of turn of the machine, while collecting water from rearward of the machine. For example, to collect water as the machine turns, the squeegee may articulate in a direction opposite to the direction of turn of the machine (e.g., as a result of frictional contact of the squeegee blades504,506with the floor surface). Thus, if the machine makes a 90 degree turn relative to the forward direction, the squeegee assembly500may move leftward relative to the forward direction. Such a motion of the squeegee assembly500may be cooperatively accomplished by the uniform downforce acting on the squeegee blades504,506, and/or vacuum between the squeegee blades504,506, which acts to keep the squeegee blades504,506pressed against the floor surface120while the machine turns, and/or the motion of the caster660and/or end wheels.

Embodiments of the present disclosure provide an interchangeable squeegee assembly that can articulate when the machine turns to effectively pick up water during wet maintenance operations such as scrubbing. The articulating mechanism according to the present disclosure may be interchangeably used with maintenance tools (e.g., scrub brushes) of different size, and may attach to exterior components of maintenance head assemblies to permit easy removal for servicing and/or replacement.

FIGS. 19-22illustrate portions of the surface maintenance machine with several of the external body panels not shown inFIGS. 1-5. As illustrated, the body panels, when added, define a storage area for storing a variety of tools and supplies740as will be described further below. With reference toFIG. 19, the mobile body of the surface maintenance machine includes a forward section700, a middle section702and a rearward section704. The terms “forward”, “rearward” and “middle section702” are referenced with respect to the direction of travel148of the machine and the transverse centerline146of the machine. For instance, as illustrated, the forward section700is positioned to the front of the transverse centerline146of the machine, the middle section702is generally centered on the transverse centerline146and the rearward section704is positioned to the rear of the transverse centerline146, when the machine moves in the direction148.

With continued reference toFIG. 19, and referring now toFIG. 20, the forward section700extends over a forward section depth700d, the middle section702extends over a middle section depth702d, and the rearward section704extends over a rearward section depth704d. As is apparent, each of the forward section depth700d, the middle section depth702d, and the rearward section depth704dcan be defined in a direction parallel to the direction of travel148of the machine. Further, the forward section700can extend over a forward section width700w, the middle section702extends over a middle section width702w, and the rearward section704extends over a rearward section width704w. In this case, each of the forward section width700w, middle section width702wand the rearward section width704wcan be defined in a direction perpendicular to the direction of travel148and/or between lateral walls116,118of the machine.

The machine can have overall dimensions configured such that at least two of the forward section depth700d, the middle section depth702d, and the rearward section depth704dare equal. Further, at least two of the forward section width700w, the middle section width702w, and the rearward section width704wcan be equal. In some examples, the forward section700and the rearward section704can have generally equal dimensions. Further, the forward section700, the middle section702and the rearward section704can all be substantially of the same dimensions.

With reference toFIG. 20and referring now toFIG. 21, body panels of the machine may define the boundaries of the storage area so as to isolate it from various components of the machine such as batteries744, solution and/or recovery tanks, sweep chamber and/or hopper, maintenance tools, and the like. For instance, the body may have a center plane166parallel to the floor surface and a generally planar top surface710positioned above the center plane166of the body and generally parallel thereto. The generally planar top surface710can be at a first distance712above the floor surface. Further, the body can have a generally planar lower surface714positioned below the center plane166of the body and generally parallel thereto. The generally planar lower surface714can be located at a second distance720below the generally planar top surface710.

With continued reference toFIGS. 20 and 21, the body panels may further include boundaries that define a storage chamber730. For instance, the body panels may include a front wall732, a rear wall734, lateral walls736,738, such that the storage chamber730is generally isolated from components of the surface maintenance machine and generally hollow to permit storage of maintenance tools and/or supplies740. As mentioned previously, “front”, “rear” and “lateral” refer to the position and orientation with respect to the direction of travel148and/or transverse centerline146. As seen inFIGS. 20 and 21, the front wall732of the storage chamber730abuts the forward section700and the rear wall734of the storage chamber730abuts the rearward section704. For instance, the front wall732can be a common boundary between the forward section700and the middle section702. Likewise, the rear wall734can be a common boundary between the middle section702and rearward section704. As seen inFIGS. 20 and 21, the storage chamber730extends over a depth730d(defined between its lateral walls736,738) substantially equal to the middle section depth702dand over a width730wsubstantially equal to the middle section width702w.

Referring back toFIG. 20, the generally planar top surface710can be located at a first distance712from the floor surface whereby, the first distance712corresponds to the machine height. In such cases, the storage chamber730can extend between the generally planar top surface710and the generally planar lower surface714of the machine body wherein the generally planar lower surface714is at a second distance720below the generally planar top surface710, such that the second distance720generally corresponds to the height of the storage chamber730. In some such cases, the second distance720is greater than about two-thirds of the first distance712. In such cases, the storage chamber730may extend over a height of about two-thirds the height of the machine.

Referring again toFIG. 21, the boundaries of the storage chamber730facilitate substantially isolating the storage chamber730from components of the machine. For instance, the storage chamber730can be fluidly isolated from a maintenance chamber742that houses one or more maintenance tools. Further, as seen inFIG. 21, components of the machine can be re-arranged so as to permit a substantially hollow middle section702for defining the storage chamber730. For instance, components of the machine such as batteries744for propelling the machine, and/or recovery tank746for collecting fluids from the floor surface, can be substantially located in the forward section700. Further, solution tank for supplying a fluid toward a floor surface may be positioned outside the middle section702. In the illustrated embodiment, for instance, the solution tank is defined peripherally around the body of the vehicle, with an inlet port748positioned in the rearward section704.

With continued reference toFIG. 21, and as indicated above, components of the machine (e.g., such as batteries744, maintenance head assemblies, solution tanks, vacuum systems, machine controls and the like), can be arranged to create a substantially hollow portion having a volume sufficient to house the storage chamber730. As shown inFIG. 21, in one example, the entirety of the batteries744and the recovery tank746can be respectively located in the forward section700, though, portions of the recovery hose749may pass around the storage chamber730. Continuing with the example illustrated inFIG. 21, a storage chamber bottom surface747can be coplanar with or below a top surface751of at least one battery positioned in the forward section700. Such embodiments permit an adequate volume of storage chamber730to store a variety of maintenance tools and/or supplies740.

Referring now toFIG. 22, the storage chamber730comprises one or more access doors for permitting access to the storage chamber730when opened. In the illustrated embodiment, the storage chamber730comprises a first access door750configured to open in a lateral direction752. The first access door750can be formed by at least portions of a lateral wall of the storage chamber730. Further, the first access door750(and in turn, the lateral walls736,738of the storage chamber730) can be generally coplanar with lateral walls116,118of the machine, such that the storage chamber730is generally confined within the lateral extents of the machine and does not protrude outside of the machine envelope. With continued reference toFIG. 22, the storage chamber730comprises a second access door754configured to open in a direction756perpendicular to the direction of opening752of the first access door750. Additionally, either, or both of the first access door750and the second access door754may be accessible from the operator platform such that the operator may access them (e.g., grasp and/or open). As is apparent fromFIGS. 19-22, the second access door754is generally coplanar with the generally planar top surface710such that the storage chamber730can remain confined within a machine envelope. In such cases, the lateral walls116,118of the machine and the generally planar top surface710may constitute at least portions of the outer boundaries of the envelope.

Referring back toFIG. 19, the storage chamber730defined in the middle section702of the machine body for storing surface maintenance tools and supplies740that an operator may use for performing one or more manual surface maintenance tasks. For instance, the operator may remove the surface maintenance tools and/or supplies740, such as spray bottles housed in a caddy800with a one or more bins804, brooms and/or mops806, wash cloths, and the like and transport them manually to a location where a manual maintenance operation is to be performed. Referring now toFIG. 21, the storage chamber730may also be configured to store debris collected from the manual maintenance, for instance, in a trash bag810, that may be positioned in the storage chamber730(e.g., using frame elements812).

As seen inFIG. 22and referring to the enlarged portions thereof illustrated inFIGS. 23A-23C, the storage chamber730can be of a modular design so as to facilitate housing individual storage modules such as a storage caddy800, one or more storage bins804, a drip catching bin for storing/collecting fluids from a mop, a debris compartment and the like. For instance, inFIG. 23A, the storage chamber730is illustrated as having a trash bag810housed therewithin, whereby the trash bag810extends substantially over the height of the storage chamber730.FIG. 23Billustrates another use of the storage chamber730, whereby the trash bag810extends over one half of the height of the storage chamber730, and a storage bin is placed in the remaining space.FIG. 23Cillustrates a further use of the storage chamber730, wherein a plurality of bins804/trays can be placed in the space within the storage chamber730instead of a trash bag810. Any such modular arrangements are contemplated within the scope of the present disclosure.

Embodiments of the surface maintenance machine with storage areas such as those illustrated herein permit an operator to store tools and supplies740for performing manual surface maintenance operations in situations where the machine may not be able to travel (e.g., areas with aisle widths narrower than the width of the machine) for collecting large dry debris or for off-the-floor manual maintenance.

Various examples have been described. These and other examples are within the scope of this disclosure.