Patent Application
20130212814
The present invention generally relates to floor surface cleaning equipment. More particularly the present invention relates to a compact side brush assembly for use with such equipment.
Surface maintenance vehicles and cleaning devices have a long history subject to gradual innovation and improvement toward improved and oftentimes automated performance in removing debris and contamination from floors. These vehicles and devices may be self-powered, towed, or pushed, and/or manually powered and may carry a human operator during cleaning operations. Such vehicles and devices include scrubbers, extractors, sweepers and vacuums, as well as combinations thereof, intended for cleaning, scrubbing, wiping and/or drying a portion of a substantially flat surface both indoors and outdoors. Many such vehicles and devices employ a side brush assembly for accessing a larger floor envelope. Such side brush assemblies make it easier to clean near walls or other obstacles without damaging the machine or the wall while at the same time widening the cleaning path of the machine to increase productivity measured as area cleaned divided by time.
The side brush assembly of such prior art cleaning vehicles often mounts at or near the side of a surface maintenance vehicle and swings outwardly away from a machine center and downwardly toward the surface to be cleaned. A lift motion of the side brush assembly is desired to raise the brush deck to provide ground clearance when the scrubbing functions are turned off. An extension/retraction motion is desired to extend the deck past the machine envelope when operating, and to retract the deck back when not operating the side brush. Portions of the side brush assembly retracted behind the machine frame are protected from damage.
Some prior art side brush assemblies have included a large number of parts, which can increase the cost and complexity of such assemblies. In addition, some prior art side brush assemblies have a large footprint on the surface maintenance vehicle that can complicate packaging the side brush assembly within the confines of the vehicle. In addition, the packaging considerations of a relatively large side brush assembly make it difficult to use the same side brush assembly design on different vehicles of different sizes.
Certain embodiments of the invention include a side brush assembly for a floor surface maintenance machine where the side brush assembly includes a brush deck, a parallel linkage assembly, a swing arm, and an actuator assembly. The brush deck carries a floor-engaging brush. The parallel linkage assembly supports the brush deck generally parallel to the floor surface and permits pivoting of the brush deck about a lift axis to raise and lower the brush deck. The swing arm is adapted to rotate about a pivot axis and is connected to the parallel linkage assembly. The pivoting of the swing arm about its pivot axis swings the brush deck towards and away from the floor surface maintenance machine. The actuator assembly includes a linear actuator and a slip link. When actuated, the actuator assembly pivots the parallel linkage assembly about the lift axis and pivots the swing arm about its pivot axis to move the brush deck to a transport mode or an operational mode.
The following drawings are illustrative of particular embodiments of the invention and therefore do not limit the scope of the invention. The drawings are not necessarily to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description. Embodiments of the invention will hereinafter be described in conjunction with the appended drawings, wherein like numerals denote like elements.
Cleaning components extend from an underside of the machine 100. For example, a scrub head 110 is shown located at a middle portion of machine 100. The scrub head 110 has a housing 112 that encloses two scrub brushes 114. The brushes 114 are driven by two electric motors. An electric actuator attached between the scrub head 110 and the housing 112 raises the scrub head 110 for transport, lowers it for work, and controls its down pressure on the floor. Additional aspects of the electric actuator and associated mechanical coupling are described in more detail hereinafter. The scrub head 110 uses two disk scrub brushes 114 rotating about parallel vertical axes. Alternatively, scrub heads may be made with only one disk scrub brush, or one or more cylindrical brushes rotating about horizontal axes. While a scrub head 110 is depicted in the drawing figures, any appliance or tool for providing surface maintenance, surface conditioning, and/or surface cleaning to a surface may be coupled to an associated machine or vehicle in accordance with the present invention.
Vehicle 100 includes a side brush assembly generally indicated as 116 for cleaning a larger floor envelope. Such side brush assemblies make it easier to clean near walls or other obstacles without damaging the machine or the wall while at the same time widening the cleaning path of the machine to increase productivity. The side brush assembly is mounted on the front, right side of machine 100 and swings outwardly away from the machine center and downwardly toward the surface to be cleaned. In
During wet scrubbing operations, water or a cleaning liquid contained in a tank 118 is sprayed to the surface beneath machine 100, in proximity to the scrub head 110. Brushes 114 scrub the surface and the soiled cleaning liquid is then collected by a fluid recovery system and deposited in a waste recovery tank 120. One embodiment of the fluid recovery system of the machine 100 includes a vacuum squeegee mounted adjacent the rear end of the machine 100. The vacuum squeegee generally comprises a squeegee 122 that extends across the width of the machine 100 and a frame that supports the squeegee 122. The vacuum squeegee also includes a vacuum port 124 that is placed in vacuum communication with a vacuum fan. The vacuum fan operates to remove liquid and particle waste collected by the vacuum squeegee 122 for deposit in the waste recovery tank 120.
In alternate embodiments, the floor surface maintenance machines 100 may be combination sweeper and scrubber machines. In such embodiments, in addition to the elements describe above, the machines 100 may also include sweeping brushes and a hopper extending from the underside of the machine 100, with the sweeping brushes designed to direct dirt and debris into the hopper. In still other embodiments, the machine 100 may be a sweeper only. In such embodiments, the machine 100 may include the elements as described above for a sweeper and scrubber machine, but would not include the scrubbing elements such as scrubbers, squeegees and fluid storage tanks (for detergent, recovered fluid and clean water). Alternatively, the machine 100 may be designed for use by an operator that walks behind the machine, or the machine may be configured to be towed behind a vehicle. Machine 100 may also be a zero turn radius vehicle and it may have steerable front or rear wheels.
Embodiments of the compact side brush assembly 116 provide for small footprint under the surface maintenance vehicle that simplifies packaging the side brush assembly 116 within the confines of the vehicle 100.
As shown in
The side brush assembly 116 is positioned proximate to the brush 117.
Referring to
One portion of the suspension and lift mechanism 206 includes a frame mount 210 that connects to linear actuator 212 with a pivoted connection that secures the linear actuator to the frame 200 via the pivotable connection to frame mount 210. The other end of linear actuator 212 is extendable and connects to frame bracket 208 with a pivoted connection. As in known in the art, linear actuator includes a leadscrew member having a thread set formed therein and has a distal end which is movable in response to leadscrew rotation. Additional linear actuators may include hydraulic or hybrid electro-hydraulic devices (not shown). The extendable end of leadscrew member has a pin-receiving aperture formed therein. A pin is inserted through an aperture in one end of frame bracket 208 and the pin-receiving aperture of the distal end to secure them together with a pivoted connection. In one embodiment, linear actuator 212 is of a compact design and has a 3.5 inch stroke. In one embodiment, linear actuator 212 is of a compact design and has a stroke less than 4 inches.
As noted above, frame bracket 208 connects to the frame 200 and pivots about frame 200 via a vertical pivot axis P100. Extension or retraction of the linear actuator 212 controls the pivot position of frame bracket 208 about vertical axis P100. As may be seen in
Frame bracket 208 connects to one end of slip link 216. Slip link 216 is a linkage having opposing spherical rod ends 218, providing pivotable connections. The other rod end 218 connects, as will be described further below, to a bracket 220 of a main arm 222. The rod ends 218 of slip link 216 spring biases its rod ends 218 via an internal spring element to retract centrally inward towards each other and shorten the length of the slip link 216. When the rod ends 218 are fully retracted, slip link 216 becomes a rigid link that will transfer or convey a compressive load from one rod end 218 (e.g., from frame bracket 208) to the other rod end 218 (e.g., main arm bracket 220) as a rigid linkage. The fully retracted length of slip 216, as measured by the distance between its rod ends 218 when they are fully retracted centrally inward, is adjustable so as to accommodate different suspension sizes and configurations. As may be seen in
As noted above, one of the rod ends 218 connects to a bracket 220 on main arm 222. Main arm 222 and second arm 224 form part of the parallel linkage assembly. Main arm 222 and second arm 224 connect to brush deck 202 via pivoted connections. One of the pivoted connections permits the main arm 222 to pivot relative to the brush deck about a horizontal axis P102. The other pivoted connection permits second arm 224 to pivot relative to brush deck about another, parallel, horizontal axis P104. The parallel linkage assembly provides the up/down motion of the brush deck 202. The parallel geometry of linkage assembly is important to keep brush deck 202 generally level (e.g., horizontal) as the brush deck 202 adjusts to floor contours. Main arm 222 also connects to swing arm 214 via a pivoted connection, having a pivot axis P106 offset from but parallel to pivot axes P102, P104. Second arm also connects to swing arm 214 via a pivoted connection, having a pivot axis P108 offset from and parallel to pivot axis P106 of main arm. As may be seen in
As noted above, both main arm 222 and second arm 224 connect to swing arm 214. To the extent that the parallel linkage assembly provides the lift axis (up and down movement) for the brush deck 202, swing arm 214 provides the inward/outward pivot axis for the brush deck 202. More specifically, swing arm 214 pivots about vertical axis P110, thereby also pivoting main arm 222, second arm 224, and most importantly, brush deck 202 inward/outward about vertical axis P110. Swing arm 214 has a hollow cylindrical portion 226 and a leg portion 228 that is either fixed to or integral with swing arm 214 extends from the cylindrical portion 226 such that the leg portion 228 is offset or eccentrically positioned relative to the cylindrical portion 226. Cylindrical portion 226 is journaled about and rotationally supported by a stationary frame shaft 230. Stationary frame shaft 230 is positioned within the hollow cylindrical portion 226 and is connected to frame 200. Vertical axis P110 is located centrally within the cylindrical portion 226 of swing arm 214. Main arm 222 and second arm 224 of the parallel linkage assembly connect to the leg portion 228. The inward and outward rotation of swing arm 214 is limited by stationary stop 232 that is connected to a plate, which is connected to frame 200 (
As may be seen in
As noted above, one rod end 218 of slip link 216 connects to bracket 220 of main arm 222 with a pivoted connection. Also as noted above, in the transport mode, frame bracket 208 has pivoted about vertical axis P100 to compress slip link 216 rod ends 218 such that slip link 216 transfers or conveys compressive load provided by frame bracket 208 from one rod end 218 (e.g., from frame bracket 208) to the other rod end 218 (e.g., main arm bracket 220) as a rigid linkage.
Also as noted above, in the operational mode, frame bracket 208 has pivoted about vertical axis P100 to stretch slip link 216 rod ends 218 against the bias of the internal spring mechanism and lengthen slip link 216 such that rod ends 218 convey a tensile force provided by frame bracket 208 on one rod end 218 (connected to frame bracket 208) that pulls on the other rod end 218 (connected to main arm bracket 220). These forces, either compressive or tensile, are provided at the pivotal connection between rod end 218 and main arm bracket 220. Since the main arm bracket 220 connection to the rod end 218 is spaced away from vertical pivot axis P110 of swing arm 214, the compressive or tensile forces create a moment arm that causes the swing arm 214 to rotate about its vertical pivot axis. Similarly, since the main arm bracket 220 connection to the rod end 218 is spaced away from the pivot (lift) axis of main arm 222, the compressive or tensile forces create a moment arm that causes the main arm 222 to rotate about its pivot axis P106. Thus, when the slip link 216 provides a compressive force during movement to the transport mode, swing arm 214 pivots inward for transportation of brush deck 202 and main arm 222 rotates above pivot axis P106 to lift up brush deck 202. In contrast, when slip link 216 provides a tensile force during movement to the operational mode, swing arm 214 pivots carrying brush deck 202 outward for a wider cleaning path and main arm 222 rotates about pivot axis P106 to push down brush deck 202. Moreover, in certain embodiments, the force that drops brush deck 202 down is great enough to push brush deck (and therefore its underlying brush) against the floor. Such a downward force provides additional scrubbing power for the brush.
In certain embodiments, the inward/outward pivot motion of brush deck is designed to occur with the brush deck in the lower position. That is, when moving from the transport mode to the operational mode, the pivot motion of main arm 222 about lift axis P106 to drop brush deck to the floor surface occurs first, followed by the pivot motion of swing arm 214 about pivot axis to move brush deck outward. Conversely, when moving from the operational mode to the transport mode, the pivot motion of swing arm 214 about pivot axis to move brush deck inward followed by the pivot motion of main arm 222 about lift axis P106 to lift brush deck from the floor surface. Such an order of motions is sometimes preferable such that the brush and its squeegee remain on the floor until they are swung within the boundary of the machine, at which point they are lifted off the floor. Such motion tends to better capture any liquid or debris under brush and direct it towards the main portion of machine for pickup.
As noted above, during movement to the operational mode, slip link 216 provides a tensile force on rod end 218 of bracket 220. The tensile force creates a moment arm that pivots swing arm 214 outward. The outward pivot continues until leg 228 of swing arm 214 abuts stop 232. At that point, swing arm 214 cannot pivot about axis P110 any further outward. Linear actuator 212, in certain embodiments, is designed to continue its extending stroke beyond the point that causes leg 228 to abut stop 232. Accordingly, further actuation of the linear actuator 212 further pivots frame bracket 208 about axis P100. Since such movement does not translate into further outward pivoting of swing arm, the tensile force on slip link 216 results in axial stretching against the spring bias of slip link 216 resulting in a lengthening of slip link 216 between its rod ends 218. Moreover, the continuing tensile force on slip link 216 maintains the moment arm that wants to rotate main arm 222 about pivot axis P106 to push down brush deck 202, thus resulting in a greater downforce on brush deck 202.
As noted above, during movement to the transport mode, slip link 216 compresses until it is a rigid link and provides a compressive force on rod end 218 of bracket 220. The compressive force creates a moment arm that pivots swing arm 214 inward. The inward pivot continues until finger 234 of swing arm 214 abuts stop 232. At that point, swing arm 214 cannot pivot about axis P110 any further inward. Linear actuator 212, in certain embodiments, is designed to continue its retracting stroke beyond the point that causes finger 234 to abut stop 232. Accordingly, further actuation of the linear actuator 212 further pivots frame bracket 208 about axis P100. Since such movement does not translate into further inward pivoting of swing arm, the compressive force on slip link 216 maintains the moment arm that wants to rotate main arm 222 about pivot axis P106 to pull brush deck 202 upward, thus pulling brush 117 upward from contact with the floor.
As noted above, the force that drops brush deck 202 down is great enough to push brush deck (and therefore its underlying brush) against the floor to provide additional scrubbing power for the brush. In certain embodiments, such as when additional downforce is desired, the suspension and lift mechanism 206 for side brush assembly 116 includes a downforce amplifier assembly that increases or amplifies the downforce on brush deck. For smaller vehicles, the downforce amplifier assembly may be eliminated or not used. The downforce amplifier assembly includes a first intensifier arm 300 and a second intensifier arm 302, and an extension spring 304 (omitted for clarity, but shown in dotted lines to indicate its position and length). First intensifier arm 300 is connected between frame bracket 208 and second intensifier arm 302, both via a pivoted connections. Second intensifier arm 302 is connected to frame 200 via a pivoted connection having a vertical pivot axis P112. A distal end of second intensifier arm 302 has an eyelet 308 through which an end of extension spring 306 is inserted. The other end of extension spring 306 is connected to an eyelet 308 mounted to main arm bracket 220. As may be seen in
As may be seen in contrast, in
Similar to the discussion of moment arms above with respect to the slip link 216, since the eyelet of main arm bracket 220 is spaced away from the pivot (lift) axis P106 of main arm 222, the tensile force creates a moment arm that causes the main arm 222 to rotate about its pivot axis P106. Thus, when extension spring 306 provides a tensile force during movement to the operational mode, main arm 222 rotates about pivot axis P106 to push down brush deck 202. Moreover, since the eyelet 308 of main arm bracket 220 is even further away from pivot axis than is the connection between slip link 216 and main arm bracket, the moment arm created by extension spring 306 is even larger than that of the slip link 216. Thus, the extension spring 306 can provide a substantial downward force to amplify the downward force already provided by slip link 216. Extension spring 306 may also provide additional torque to pivot the brush deck 202 outward since the eyelet of main arm bracket 220 is spaced away from the pivot axis P112 of swing arm 214. The tensile force creates a moment arm that causes the swing arm 214 to rotate about its pivot axis P112. Many types of extension springs 306 may be used. For applications where a larger downforce is desired (e.g., a deeper scrub), an extension spring 306 is a larger spring constant may be employed. However, for applications such as sweeping, where a relatively smaller downforce is desired, a spring with a smaller spring constant may be employed. Moreover, for some sweeping applications that require very little downforce, extension spring could be removed completely, leaving slip link to provide the main downforce.
During use of the vehicle 100 and when the side brush assembly 116 is deployed, slip link 216 also permits brush deck 202 to rise and fall while passing over any undulations in the floor without also requiring actuation of the linear actuator 212. As noted above, when in the operational mode, the rod ends 218 of slip link 216 are stretched. If the brush 117 encounters floor undulations or obstructions, the brush 117 will be pushed upward and/or rearward, which translates to inward movement. In order to accommodate such upward and/or inward forces from undulations or obstructions, slip link 216 will stretch further, via its rod ends 218, against its spring bias to permit limited lift and inward movement. After the undulation and/or obstruction has been traversed, the spring bias of the slip link 216 will pull the rod ends 218, creating a downforce that causes the brush deck to return back to its full down and out operational position. The linear actuator need not be engaged during such process since the slip link can provide the limited movement needed to permit brush deck 202 to rise and fall or pivot inward while passing over any undulations in the floor. In the instance when brush deck encounters dips or valleys in the floor surface, the downforce from one or both of the stretched slip link 216 (from being in the operational mode) or the extension spring will cause the brush deck to rotate downward against the dip or valley to maintain contact with the floor even without any actuation of the linear actuator.
In the foregoing detailed description, the invention has been described with reference to specific embodiments. However, it may be appreciated that various modifications and changes can be made without departing from the scope of the invention.
The present application claims priority to co-pending U.S. Provisional Patent Application Ser. No. 61/599,771, filed Feb. 16, 2012, the disclosure of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61599771 | Feb 2012 | US |
