VACUUM HEAD FOR SWIMMING POOLS AND SIMILAR STRUCTURES

[0001] This application claims the benefit of earlier filed U.S. Provisional Patent Application 60/760,394 filed Jan. 20, 2006 by the applicants herein, the disclosure of which is incorporated herein by reference.

[0002] The present invention relates to vacuum heads of the type used to vacuum debris from the surfaces of swimming pools, hot tubs, spas, and the like and, more particularly, to such vacuum heads having improved operational efficiency and ease of use.

[0003] Known vacuum heads typically include pivoting caster-type wheels, non-pivoting rollers, and/or bristle assemblies to support the vacuum head a selected distance above the surface being swept. One problem with existing designs is the propensity for the wheels, rollers, and/or bristles to disturb the debris such that a water-borne “cloud” of debris is created or formed above the vacuum head thereby limiting the efficiency of the device.

[0004] An improved vacuum head is defined by upper and lower sub-housings that are secured together to form the vacuum head assembly. A set of spherical balls are captured in appropriately sized ball-receiving pockets or sockets formed between the upper and lower sub-housings to support the vacuum head assembly a selected distance above the surface being swept. The ball-receiving sockets include a “stand-off” formation to minimize the probability of a ball-receiving socket becoming clogged with debris sufficient to the impair the ability of the ball to roll within its ball-receiving socket. The use of balls as the rolling members allows omnidirectional control of the vacuum head while minimizing the propensity for disturbing the debris in the vicinity of the vacuum head and the formation of a undesired water-borne “cloud” of debris. The peripheral edges of the vacuum head are radiused to provide a low-resistance flow path to the underside of vacuum head to also allow the vacuum head to pull any water-borne debris from areas above or immediately adjacent the vacuum head in addition to vacuuming debris on the pool surface beneath the vacuum head.

[0005] The full scope of applicability of the present invention will become apparent from the detailed description to follow, taken in conjunction with the accompanying drawings, in which like parts are designated by like reference characters.

[0023] An exemplary embodiment of a vacuum head is shown in perspective view in FIG. 1 and in opposite side views in FIGS. 2 and 3 and is generally designated therein by the reference character 10. As shown, the vacuum head 10 has a generally triangular planform with apices or corners 12, 14, and 16 thereof generously radiused to provide a shape well-suited for sweeping in the corner areas and the curved areas of a swimming pool or spa. A tubular outlet 18 extends from the upper portion of the vacuum head 10 for connection to a vacuum hose of the type typically used in swimming pools and spas; these hoses typically having a 1.5 inch inside diameter adapted to fit over the tubular outlet 18 with a friction fit. Additionally, a connection structure 20 is provided for a pivoting connection to a fixed-length or adjustable-length ‘stick handle’ of the type used for cleaning swimming pools and the like. As explained below in relationship to FIG. 4, the vacuum head 10 is preferably assembled from upper and lower interfitting sub-housings or piece-parts that are held together by screw fasteners 22 or equivalent devices. As shown in the side views of FIGS. 2 and 3, spheroid-like elements 24 are located within and spaced from the edges that define the planform of the vacuum head; these ball-like elements 24 extend from the underside of the vacuum head 10 and provide omnidirectional capability.

[0024] FIG. 4 is an exploded perspective of the vacuum head 10 and shows an upper piece-part 26 separated from the lower piece-part 28. The upper piece-part 26 includes a “U”-shaped opening 30 or cut-out through which the outlet 18 and the connection structure 20 of the lower piece-part 28 extend. Threaded inserts 32 are carried in or embedded in appropriate openings in the lower piece-part 28 and engage the threaded fastens 22 to hold the upper and lower piece-parts, 26 and 28, in their assembled relationship.

[0025] In the preferred embodiment, the upper piece-part 26 is formed from a corrosion-resistant metal (i.e., stainless or stain-resistant steel) that provides sufficient negative buoyancy to the assembled vacuum head to allow convenient use while the lower piece-part 28 is fabricated from a suitably molded plastic or similar material. If desired, the upper piece-part 26 can be formed from plastic and the lower piece-part 28 from metal, or, alternatively, both the upper piece-part 26 and the lower piece part 28 can include both molded plastic and metal sub-components to provide equivalent functionality. While the use of metal components is desirable, a vacuum head fabricated entirely of plastic materials is equally suited. While threaded fasteners and threaded inserts are shown in the figures, self-tapping screws and other types of fasteners, including more permanent rivets, can be used to attach or secure the upper and lower piece-parts.

[0026] As shown in FIG. 5, the tubular outlet 18 and the connection structure 20 of the lower piece-part 28 extend or pass through the “U”-shaped opening 30 of the upper piece-part 26 of the assembled structure. As shown in the cross-section of FIG. 6, the upper piece-part 26 is received by the lower piece-part 28 with each of the ball elements 24 captured or contained within an appropriately sized pocket or ball socket 34 that is defined between the assembled upper and lower piece-parts, 26 and 28.

[0027] As shown in the expanded detail of FIG. 7, each ball-element socket 34 is defined by appropriate shaping of a portion of the upper piece-part 26 to form a dome formation 36 that includes at least one inwardly extending stand-off 38 that presents a bearing surface 40 to the ball-element 24. The lower piece-part 28 includes an opening defined by a part-spheroidal surface 42 so that the ball-element 24 is “captured” or retained in the socket 34 defined between the dome formation 36 in the upper piece-part 26 and the opening in the lower piece-part 28. The dimensional relationship between the ball-element 24 and the retaining structure is such that each ball-element 24 is free to rotate in all possible directions (i.e, omnirotational) as the vacuum head is moved or drawn across the surface of the pool being vacuumed or swept.

[0028] As can be appreciated from FIG. 7, the stand-off 38 provides bearing support surface 40 for the ball-element 24 while also creating substantial clearance spaces within the socket 34. During normal operation, any debris being vacuumed will be in the vacuum stream moving toward and into the outlet tube 18 thus keeping the ball and socket relatively clean and free of debris; however, any debris that does find itself in socket space 34 will be expelled out through the open areas between the top 26 and bottom 28 since the upper piece-part 26 is formed as a shell-like member. Thus, the ball-element 24 can rotate freely in any direction, even in those situations in which debris, such as leaf-parts, seeds, pollen, plant-fragments, algae, and the like, might enter the clearance space within the socket 34, without adversely affecting operation of the ball-element 24.

[0029] The ball-elements 24 can be formed from any suitable material including high-density polyethylene, nylon, delrin, ultra-high molecular weight plastics, etc.; metals, such as stainless and stain-resistant steels, are not excluded.

[0030] As shown by reference character 44 in FIG. 7, the upper piece-part 26 is received within the lower piece-part 28 to form the interfitted assembly. The outer perimeter of the lower piece-part 28 defines a ‘bumper’ for those surfaces that are expected to impact or abrade against the pool surfaces. The outer perimeter 48 of the of the lower piece-part 28 is preferably radiused to encourage water flow from areas above the plane of the vacuum head 10. For example and shown by the flow arrows 50 on the right in FIG. 7, the radiused outer perimeter 48 of the lower piece-part 28 encourages water flow from those areas in which a debris cloud often forms when using vacuum heads 10. Depending upon the radius “r” of the outer perimeter 48 of the lower-piece part 28, the flow will tend to “follow” and move along the curved surface of the outer perimeter 48 in a manner consistent with the Coanda effect. This steering of the flow tends to increase flow velocity to assist pulling debris-laden water from any debris cloud adjacent the vacuum head and assist in loosening any debris and entraining the debris into the flow to thereby increase operational efficiency. In general, a value for the radius “r” can be approximately 0.25 inches to 2.0 inches or so. As can be appreciated from FIGS. 7 and 8, the upper piece part 26 is received by the lower piece-part 28 so that substantially all the flow is contiguous or adjacent the radiused portion of the lower piece-part 28.

[0031] As shown on the left in FIG. 7, the lower piece-part 28 is formed with a shallow depression 52 the center portion of which connects to the outlet 18 so that the debris-containing flow will follow a pathway into the outlet tube 18.

[0032] FIG. 8 shows the operational flow pattern of the vacuum head 10 (shown in a simplified outline); as shown, water enters the underside of the lower piece-part 28 about the entire periphery thereof and flows thereunder entraining debris therein and flows into the shallow cone-like opening 52 into the tubular outlet 18.

[0033] In the embodiment shown above, the socket 34 that receives the ball element 24 is defined between the upper and lower piece-parts, 26 and 28. As shown in FIGS. 9, 10, and 11, the ball elements 24 can be carried in cartridge-like holders that, in turn, are inserted into appropriate cartridge-receiving pockets. More specifically and as shown in FIG. 11, each ball element 24 is carried or contained in a holder or cartridge 54 that is molded or otherwise fabricated as a cylinder-like member having appropriate interior surfaces to provide rolling support for the ball element 24. As shown, a plurality of slots 56 (e.g., four) extend partly along the side of the cartridge 54 so that each ball element 24 can be “snapped” into its respective cartridge 54. Thereafter and as shown in the view of FIGS. 9 and 10, each cartridge 54 can be inserted into an appropriately formed pocket 58 formed in the upper piece-part 26. The cartridges 54 can be retained in place by any suitable means including a threaded or bayonet-type connection, a press or snap fit, and/or an adhesive or cemented connection or by ultrasonic bonding. While not specifically shown in FIGS. 9-11, the cartridges 54 include a formation facing the ball element 24 like that of formation 38 shown in FIG. 7 to provide an enlarged volume within the ball socket 34.

[0034] A further variant of the upper piece-part is shown in FIGS. 12, 13A, 13B, and 14; as shown those areas designed to accept a ball element 24 are defined by rib-members 60 and 62 with a stand-off 64 at the intersection thereof. As shown in the detail of FIGS. 13A, 13B, and 14, the ribs 60 and 62 are shaped to form surfaces 66 that effectively constrain the ball element 24; stand-off 64 functions in the same manner as the standoff 38 shown in FIG. 7.

[0035] In the embodiments described above, a single stand-off has been presented, as can be appreciated, plural stand-offs, including a stand-off or stand-off in positions other than shown in the figures, are not excluded.

[0036] The embodiments shown in the figures have a principally triangular planform; as can be appreciated, other forms are suitable including, for example, a round or ellipsoidal planform, a square or rectangular planform with one or more sides thereof radiused as appropriate (as exemplified in dotted-line illustration form in FIG. 15) or, as shown in dotted-line illustration in FIG. 16, a planform having a “quarter-moon” configuration in which the inner radius side is formed at a radius of curvature to approximately conform to the radius of curved steps that are a common feature of many swimming pools. While the above-described embodiments have four ball elements, a larger or smaller number may be used; for example and as shown in FIGS. 15 and 16, two and three balls elements can be used depending upon the planform of the particular embodiment.

[0037] While each of the embodiment described above include some type of stand-off or stand-off like formation, it may also be desirable to fabricate the embodiments without a stand-off, as shown in FIG. 17 which illustrates a cross-section view of an upper piece-part 26 in which the molded-in-place sockets do not have an inwardly projecting formation.

[0038] The vacuum head 10 in accordance with the present design allows supported omnidirectional movement while minimizing and/or eliminating the probability of debris impeding the operation of the ball-elements 24 and providing a flow pattern that also draws water from those areas in which debris clouds are known to form during the debris sweeping operation.

[0039] As will be apparent to those skilled in the art, various changes and modifications may be made to the illustrated embodiment of the present invention without departing from the spirit and scope of the invention as determined in the appended claims and their legal equivalent.