Patent Application
20160333600
This invention relates to automatic pool cleaners (APCs) configured to move autonomously within liquid-containing bodies such as swimming pools and spas and more particularly, although not necessarily exclusively, to components of APCs that frictionally contact surfaces of the pools and spas.
Commonly-owned U.S. Patent Application Publication No. 2011/0314617 of van der Meijden, et al., discloses various components of APCs. Among components illustrated in the van der Meijden application are devices referenced as “scrubbers.” As detailed in the van der Meijden application, an exemplary scrubber may include blades, a shaft, and optionally a gear.
Also described in the van der Meijden application as another optional part of a scrubber is a “wear surface.” If present, the wear surface may be located centrally among the blades of the scrubber and coaxial with the shaft. At least at times in use, the wear surface may contact a surface to be cleaned. See id., p. 2, ¶0028.
Even though the van der Meijden application contemplates frictional contact between the wear surface and surfaces of a pool or spa, additional scrubbing action may be desirable—at least at times—for cleaning purposes. Including brushes spaced from (i.e. not coaxial with) the shaft of a scrubber also may be advantageous, as may be utilizing bristles which contact a surface as the scrubber rotates about the shaft. Removably attaching the brushes to a scrubber further may be beneficial, as in such cases the brushes may be removed from the scrubber when not needed.
The present invention provides these types of brushes useful especially (although not necessarily exclusively) with the scrubbers and APCs of the types identified in the van der Meij den application. Brushes of the invention may clip to a hub of a scrubber so as to attach to, and detach from, the scrubber easily. The brushes also preferably flex when a scrubber rotates.
At least some versions of the brushes may include fingers having bristles protruding outward on either or both of opposed sides of the fingers. Prior to rotation of the scrubbers, the fingers nominally are generally perpendicular to the surface on which the associated APC rests. As scrubbers rotate, however, the fingers flex (e.g. lay over) and become more parallel to the surface. Flexing of the fingers in this manner in turn causes bristles on one side of fingers to become more perpendicular to the surface, thus readily frictionally contacting it.
Because in use scrubbers of the present invention rotate about an axis generally perpendicular to the pool surface, their brush speeds relative to the surface are faster than those of passive devices (which typically are dragged along the surface) or rollers (which typically rotate about an axis parallel to the surface and in the same direction as the wheels of the cleaner). Such rotation also requires less surface-area contact between the brushes and pool surface to scrub an equivalent width of pool surface than would a roller, whose length must span that entire width. This decreased surface-area contact of the brushes produces less resistance on the drive system of the APC than would rollers, potentially enhancing the longevity and robustness of the drive system.
Brushes may be attached as desired to a scrubber. Presently preferred is that at least two brushes be used with a scrubber and positioned symmetrically about the shaft. Fewer or more than two brushes may be used in connection with any particular scrubber, however, and conceivably more than one brush may be attached in a particular location.
It thus is an optional, non-exclusive object of the present invention to provide components for APCs.
It also is an optional, non-exclusive object of the present invention to provide improvements to scrubbers of the type identified in the van der Meij den application.
It is another optional, non-exclusive object of the present invention to provide brushes configured to contact to-be-cleaned surfaces.
It is an additional optional, non-exclusive object of the present invention to provide brushes that may clip, or otherwise attach, to scrubbers so as to rotate as the blades rotate.
It is, moreover, an optional, non-exclusive object of the present invention to provide brushes that include flexible fingers with bristles protruding therefrom.
It is a further optional, non-exclusive object of the present invention to provide brushes whose fingers flex as their associated blades rotate, thus causing contact between their bristles and a to-be-cleaned surface of a pool or spa.
It is yet another optional, non-exclusive object of the present invention to provide brushes which rotate about an axis perpendicular to the to-be-cleaned surface so as to produce faster speeds and less load on drive systems than do certain passive devices and rollers.
Other objects, features, and advantages of the present invention will be apparent to those skilled in relevant fields with reference to the remaining text and the drawings of this application.
Depicted in
Consistent with the discussion in the van der Meijden application, blades 14 preferably are “semi-rigid” in nature, meaning that they have sufficient flexibility to accommodate passage into inlet 21 of APC 22, without blockage, of at least some larger types of debris often found in outdoor swimming pools. The term “semi-rigid” also means that blades 14 nevertheless have sufficient rigidity to move volumes of water toward the inlet 21 of the cleaner as they rotate about shaft 18. A presently-preferred material from which blades 14 is made remains molded thermoplastic polyurethane, although other materials may be used instead.
Scrubber 10 advantageously may include six blades 14 extending radially from shaft 18. Fewer or greater numbers of blades 14 may be employed as appropriate, however. As illustrated in
As shown in
The exemplary attachment assembly 26 of
Shown especially in
Also included as parts of brush 42 are brush body 54, fingers 58, and bristles 62. Fingers 58 depend from body 54, with each finger 58 comprising opposed major sides 66A-B. Bristles 52 protrude outward from these major sides 66A-B. Although
Fingers 58 beneficially are flexible. Accordingly, as shown in
Moreover, because scrubber 10 rotates about an axis perpendicular to the to-be-cleaned surface, the speed of movement of brushes 42 (and hence of bristles 52) relative to the surface may be faster than that of passive devices which merely are dragged along the surface. This relative speed of movement likewise may be faster than that of rollers, which typically rotate about axes parallel to the surface and in the same direction as the wheels or tracks of an associated cleaner. Rotation of scrubber 10 about the perpendicular axis also requires approximately fifty percent less surface-area contact between brushes 42 and the pool surface to scrub an equivalent width of pool surface than would a roller, whose length must span that entire width. This decreased surface-area contact of brushes 42 produces less resistance on the drive system of APC 22 than would rollers, potentially enhancing the longevity and robustness of the drive system.
If scrubber 10 is configured to rotate only in one direction, bristles 52 need necessarily be present only on whichever of major sides 66A or 66B is the “leading” side for purpose of the rotation (as the other, “trailing” major side will flex away from the to-be-cleaned surface). It nevertheless may be advantageous to include bristles 52 on the trailing major side 66B or 66A of brush 42 so that, when bristles 52 on the leading side wear, brush 42 may be switched to a circumferentially opposite location on scrubber 10 so that the previously-trailing side becomes the leading side and presents unworn bristles 52 to the to-be-cleaned surface. This switch effectively can double the useful life of a brush 42. (And of course, if scrubber 10 ever is configured to rotate both clockwise and counterclockwise, including bristles 52 on both major sides 66A-B may be valuable.)
The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention. Also, although “pool” and “spa” are sometimes used separately, any reference to “pool” herein may include a spa, hot tub, or other vessel in which water is placed for swimming, bathing, therapy, or recreation. Finally, incorporated herein in their entirety by this reference are the contents of the van der Meij den application.
