WO2000047844A1

WO2000047844A1 - Automatic swimming pool cleaner discs

Info

Publication number: WO2000047844A1
Application number: PCT/US2000/003309
Authority: WO
Inventors: Chris A. Rice
Original assignee: Zodiac Pool Care, Inc.; Zodiac Pool Care Europe
Priority date: 1999-02-10
Filing date: 2000-02-08
Publication date: 2000-08-17
Also published as: AU3486300A; WO2000047844A9

Abstract

Discs for devices such as automatic swimming pool cleaners are disclosed. The discs include a central aperture circumscribed by a central portion shaped generally in the form of a truncated cone. Forming discs in this manner more appropriately matches them to the structures of footpads which they surround in use, permitting greater amounts of the undersides of the discs to remain in contact with the surfaces to be cleaned.

Description

AUTOMATIC SWIMMING POOL CLEANER DISCS

FIELD OF THE INVENTION This invention relates to automatic swimming pool cleaners and more particularly to such cleaners having discs devised so as to increase the area of their undersides adapted to contact the surface of a pool to be cleaned.

BACKGROUND OF THE INVENTION U.S. Patent Nos. 4,351,077 to Hoffman and 4,642,833 to Stoltz, et al., incorporated herein in their entireties by this reference, disclose automatic, water- interruption-type suction swimming pool cleaners having flexible annular discs. These discs are typically mounted near the inlets of the suction cleaners and designed to contact pool surfaces when in use. By doing so, the discs decrease the tendency of the cleaners to disengage from pool surfaces, particularly when the cleaners are negotiating transition regions between walls and floors.

U.S. Patent No. 5,465,443 to Rice, et al, likewise incorporated herein in its entirety by this reference, details various discs useful for automatic swimming pool cleaners. Also described therein is an exemplary footpad about which the discs may be attached to cleaners. FIG. 4 of the Rice, et al. patent provides a cross-sectional view of such a footpad, which includes an annular recess in which the central portion of a disc may be fitted.

Because the annular recess of the footpad is above its base, the central portion of the disc cannot abut the surface to be cleaned. FIG. 4 of the Rice, et al. patent illustrates this fact, showing a gap between the underside of the disc and the horizontal line designated an "axis" in the text. Although the flexible nature of the disc sometimes permits its peripheral region to contact the surface on which the cleaner is functioning (as again shown in FIG. 4 of the Rice, et al. patent relative to the horizontal line or axis), the design of the footpad and minimum rigidity requirements for successful use of the disc preclude its being able to drape sufficiently to fill the gap or provide more constant contact of its periphery with the surface to be cleaned. The result is a less-than-optimal engaging force being created, as some of the disc only occasionally or never contacts the pool surface of interest.

Disclosed in published International Patent Application No. PCT/US 97/ 17631 ("the International Application") of Baracuda International Corporation and Sweepy International S.A. is an integrally-molded footpad and disc for an automatic swimming pool cleaner. The International Application likewise illustrates gaps between the underside of the various discs referenced therein and the (imaginary) surface to be cleaned. To enhance the surface-engaging ability of the discs, the International Application contemplates increasing the flexibility of the outer edges of the base of the footpad and joining the footpad and disc with a ring of "thin section material. "

SUMMARY OF THE INVENTION The present invention provides an alternative means for enhancing the surface-engaging ability of a disc for an automatic swimming pool cleaner. The invention is especially useful with cleaners for which separate footpads already are available, as discs embodying the invention are designed to complement the structures of those footpads. Such discs conceivably could be integrally formed with footpads, although the resulting structure would differ from those illustrated in the International Application.

Unlike conventional swimming pool cleaner discs, those of the present invention include a central portion (surrounding a central aperture) which is not flat, but rather is shaped generally in the form of a truncated cone. Shaping the central portion in this manner more appropriately matches it to the structure of the footpad, permitting a greater amount of the underside of the disc to remain in contact with the surface to be cleaned. It also minimizes undesirable "folding," "buckling," or deformation of the disc sometimes occurring in the area surrounding the central portion and at its periphery when the disc is in use. Conventional molding techniques permit formation of discs as described in this paragraph, with their central portions being of sufficient rigidity to prevent any deformation in use from wholly undermining the benefits addressed herein.

Discs of the present invention optionally may include peripheral fins such as those shown in the Rice, et al. patent. Alternatively, the fins may be grouped in threes, with the tongues associated with the first and third fins of a group being mirror images. Other optional features of each disc include a ramp projecting from its lower surface and a series of spaced slits, both as described in the Rice, et al. patent. Again, alternatively, slits associated with discs of the present invention need not be limited to the rear sections of the discs.

It is therefore an object of the present invention to provide discs for automatic swimming pool cleaners.

It is also an object of the present invention to provide swimming pool cleaner discs having central portions which are not flat. It is a further object of the present invention to provide pool cleaner discs whose central portions are shaped generally in the form of a truncated cone surrounding a central aperture.

It is another object of the present invention to provide discs having more area adapted to contact a surface to be cleaned than conventional discs. It is an additional object of the present invention to provide discs which minimize undesirable deformation either at or adjacent their peripheries or in their areas surrounding the central portions when the discs are in use.

It is yet another object of the present invention to provide swimming pool cleaner discs optionally having any or all of fins, ramps, and slits. Other objects, features, and advantages of the present invention will be apparent with reference to the remainder of the text and the drawings of this application.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the upper surface of a disc of the present invention. FIG. 2 is an elevational view of the disc of FIG. 1.

FIG. 3 is a cross-sectional view of a portion of the disc as shown in FIG. 2.

FIG. 4 is a plan view of the underside of the disc of FIG. 1.

FIG. 5 is a plan view of a portion of the upper surface of the disc of FIG. 1.

DETAILED DESCRIPTION

FIGS. 1-5 illustrate disc 10 of the present invention. Disc 10 defines a central aperture 14, nominally circular, in which a footpad of an automatic swimming pool cleaner may be received, for example. Disc 10 also defines a generally planar upper surface 18, a periphery 20, and, as shown in FIGS. 2-4, a lower surface 22. Extending upward from and spaced about upper surface 18 are fins 26, which assist disc 10 in maneuvering over many objects (such as drains, lights, valves, and nozzles) projecting from internal surfaces of pools. Fins 26 additionally extend beyond periphery 20, causing them to contact most projections before the remainder of disc 10.

FIGS. 1-3 also detail the serpentine nature of periphery 20. The shape of periphery 20 defines multiple tongues 30, increasing the flexibility of disc 10 and on which an equivalent number of fins 26 are positioned. Although thirty-six tongues are shown in FIG. 1, such number of tongues (and fins) is not required and may vary as necessary or desired. Openings 34 through disc 10 enable fluid to pass between upper and lower surfaces 18 and 22 of disc 10 when in use, maintaining a boundary fluid layer between the lower surface 22 of disc 10 and the adjacent surface of the pool or other structure to be cleaned.

Shown in FIG. 3 is ramp 38, projecting from adjacent lower surface 22 of disc 10 and positioned concentrically about central aperture 14. Ramp 38 promotes a smooth transition to the bottom of the footpad (or other component) received by central aperture 14, facilitating unobstructed movement of a swimming pool cleaner associated with the footpad. FIGS. 2-3 similarly disclose radius 42 existing between fins 26 and lower surface 22 of disc 10, providing a smooth transition therebetween.

In an embodiment of the invention consistent with FIGS. 1-4, fins 26 are spaced approximately every 10° about periphery 20. This spacing of fins 26 precludes sufficiently small-diameter objects from becoming entangled between adjacent fins 26 as an associated swimming pool cleaner moves about the surfaces of a pool. Instead, fins 26, including radii 42 and the remainders of their curved leading edges 46, are designed to ride over the objects, thereby carrying the associated swimming pool cleaner over the obstacles as well. Evenly spacing fins 26 about periphery 20 and having them extend radially from periphery 20 cause disc 10 to be more flexible than, for example, having the entirety of its periphery 20 raised (like a dinner plate). Fins 26 additionally assist in bending disc 10 to remain in contact with vertical or angled walls extending from the bottom surface of the swimming pool.

FIG. 3 details various angular and distance relationships between a fin 26 and disc 10. As shown in FIG. 3, leading edge 46 of fin 26 forms an angle "f ' with axis 48, an extension of a radius of lower surface 22, while "D" describes the distance between the uppermost portion 49 of fin 26 and axis 48. In at least one embodiment of the invention, f is approximately 45° and D equals 1.20 inches. Fins 46 may be made of plastic or other flexible material and integrally molded with disc 10, facilitating uniformity of these angular and distance relationships between fins 26 of a disc 10 and between discs 10 themselves. In some embodiments, disc 10 has an approximate diameter of sixteen inches measured from the center of central aperture 14 to the outermost extension of fins 46.

Intermediate central aperture 14 and upper surface 18 is central portion 50. As detailed in FIGS. 1-3, central portion 50 provides a transition region between the generally planar upper surface 18 and central aperture 14, projecting above upper surface 18 so as to elevate central aperture 14 relative thereto. In some embodiments of disc 10, central portion 50 projects above upper surface 18 by approximately one-third inch, the approximate distance between the base and annular recess of certain commercially-available footpads. The material from which central portion 50 is made is sufficiently rigid to maintain central aperture 14 elevated above upper surface 22 even when disc 10 is not in use. This is well-illustrated in FIG. 2, which provides an elevational view of disc 10. However, no special material is required to make disc 10; instead, the material need not be any different than that used for conventional pool cleaner discs.

FIGS. 1 and 3 detail components of central portion 50. As shown therein, central portion 50 comprises first and second annular sections 54 and 58, respectively. First annular section 54, which bounds central aperture 14, is generally flat, effectively providing a reinforced area designed to be fitted into the annular recess of a footpad. Second annular section 58, which circumscribes first section 54, has the general shape of a truncated cone, thereby furnishing elevational transition from upper surface 18 to first section 54 and central aperture 14.

FIG. 3 additionally illustrates the increased amount of lower surface 22 available to contact the surface to be cleaned when disc 10 is in use. Of the surface S shown (coincident with axis 48) in FIG. 3, for example, only the limited portion between marks Dl and D2 (beneath first and second annular sections 54 and 58) is not contacted by disc 10, and some of even that limited portion (between marks Dl and D3) would be contacted by the base of the footpad beneath first annular section 54. Thus, when a pump or other device acts to reduce the pressure in the area around the footpad, a greater amount of lower surface 22 adheres to the surface on which the cleaner is operating. The result is an enhanced ability of the cleaner to maintain its progressive, incremental movement in the pool rather than toppling over or commencing to float, for example.

Detailed in FIG. 4 is lower surface 22 of disc 10. Shown on lower surface 22 are webs 62, which may be elongated regions where the thickness of disc 10 is decreased substantially. Disc 10 thus may be torn or cut along webs 62 to form radially- spaced slits at particular intervals. In preferred embodiments of disc 10, webs 62 are sufficiently fragile that a slit is formed from each as the disc 10 is removed from the mold in which it is formed. Alternatively, webs 62 may be crafted so as to survive removal from a mold intact yet fragile enough to be torn manually or cut, for example, with a utensil such as a knife. If present, webs 62 may extend radially from vertices 66 of adjacent tongues 30 to openings 34. Doing so facilitates their creation in a mold. It also eases their tearing or cutting by providing convenient terminal points or boundaries for the slits. Webs 62 further may be provided at regular intervals (e.g., 30°) about periphery 20, increasing the symmetry of disc 10, or positioned on disc 10 other than at vertices 66 if appropriate or desired.

FIG. 5, finally, details a preferred arrangement of vertices 66. Each vertex 66A from which a web 62 is to begin may form a more acute angle than those vertices 66B adjacent to it. This sharper angle of vertices 66A assists cutting or tearing of webs 62 to form any desired slits. As shown in FIG. 5, each third vertex 66 about periphery 20 has such a sharper angle; when webs 62 are torn or cut, therefore, flaps 70 (see FIG. 4), each containing three fins 26 and tongues 30, are created. Those skilled in the art will, of course, recognize that webs 62, vertices 66, and flaps 70 are optional; periphery 20 of disc 10 may instead assume other shapes or have characteristics other than those expressly described herein. As illustrated, however, each first tongue 30A of a flap 70 is a mirror image of each third tongue 30B of the same flap 70.

The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Further modifications and adaptation 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.

Claims

We claim:

1. A disc adapted for use as part of an automatic swimming pool cleaner, comprising: a. an upper surface; b. an aperture for receiving the automatic swimming pool cleaner; and c. a portion intermediate the upper surface and aperture and projecting above the upper surface so as to elevate the aperture above the upper surface.

2. A disc according to claim 1 in which the portion comprises a section having the general shape of a truncated cone.

3. A disc according to claim 2 in which the portion further comprises another section which is flat and bounds the aperture.

4. A disc according to claim 3 further comprising a lower surface and a plurality of regions of elongated web material of reduced thickness.

5. A disc according to claim 4 further comprising a periphery defining a plurality of radially-spaced tongues.

6. A disc according to claim 5 in which a vertex separates adjacent tongues, each region of elongated web material of reduced thickness terminating at such a vertex.

7. A disc according to claim 6 in which (i) the number of regions of elongated web material of reduced thickness is less than the number of vertices separating adjacent tongues and (ii) each vertex at which such a region of elongated web material of reduced thickness terminates differs from each vertex at which no region of elongated web material of reduced thickness terminates.

8. An automatic swimming pool cleaner having the disc of claim 1.

9. An automatic swimming pool cleaner disc comprising: a. an upper surface; b. a lower surface; c. a periphery; d. means, comprising a central aperture, for receiving an automatic swimming pool cleaner; and e. a central portion intermediate the upper surface and central aperture and having a conically-projecting section so as to elevate the central aperture relative to the upper surface.

10. A disc according to claim 9 in which the area of the central portion is much less than the area of the lower surface.

11. A disc having a nominal thickness and adapted for use as part of an automatic swimming pool cleaner, comprising: a. an upper surface; b. a lower surface; c, a periphery; d. a plurality of fins integrally formed with and extending upward from the upper surface beyond the periphery; e. means, comprising a central aperture, for receiving the automatic swimming pool cleaner; f. a central portion connecting the upper surface and aperture and projecting above the upper surface so as to elevate the aperture above the upper surface, the central portion comprising: i. a first section having the general shape of a truncated cone; and ii. a second section adjacent thereto and which is flat and bounds the aperture; and g. a plurality of radially-spaced regions of elongated web material of thickness less than the nominal thickness and terminating at or near the periphery.