Cleaner with high pressure cleaning jets

[0001] “This is a divisional application of U.S. Ser. No. 10/109,689, filed Mar. 29, 2002, now U.S. Pat. No. 6,742,613, which is a division of U.S. Ser. No. 09/237,301 filed Jan. 25, 1999, now U.S. Pat. No. 6,412,133, the disclosure of which is incorporated herein its entirety by reference.”

[0002] This invention relates to hand-powered and self-propelled pool and tank cleaners that draw water containing dirt and debris from the surface beneath the moving pool cleaner for entrainment in a filter.

[0003] One of the most common problems that occurs in the disrupting of the efficient operation and pre-determined movement patterns of an automated swimming pool cleaner are discontinuities in and obstacles protruding from the bottom surface of the pool. When a self-propelled cleaner encounters and attempts to pass over or around an obstacle, it can become immobilized, particularly if the obstacle engages the opening of the vacuum intake. One approach to solving this problem has been to design the cleaner so that its baseplate and associated water intake is raised as high as possible from the surface to be vacuumed. However, the higher the intake, the less effective the vacuuming becomes. Debris is also left behind when the cleaner is moving rapidly. To counter these problems, the pool cleaner is programmed to move about its route at a rather sluggish pace. The result is that it may take many hours to clean an average size swimming pool.

[0004] It has also been proposed to equip the pool cleaner with flexible intake adapters to enhance the surface vacuuming ability of the cleaner. The intake adapters are also subject to being immobilized on steps or other protruding obstacles.

[0005] A further general problem of effectively and efficiently cleaning the bottom surface exists where the dirt and debris is heavy and/or when the pool has not been regularly cleaned and the movement of water into the intake ports in the bottom or baseplate of the pool cleaner is not sufficient to create the required turbulence at the surface to disturb and lift the dirt and debris into suspension so that it can be drawn to the intake port.

[0006] This invention relates to an improvement in the cleaning methods and apparatus that overcome the above-described shortcomings of pool cleaners of the prior art, whether hand-powered or of the self-propelled and robotic type. The introduction of water jets under the cleaner body, directed inboard and generally toward its center from its sides, agitates and lifts the dirt and debris, which is then moved toward the one or more baseplate intake ports, to greatly enhance the cleaning ability of the apparatus. The suspended dirt and debris become semi-buoyant under the force and turbulence of the jetted water.

[0007] In a preferred embodiment, a plurality of the directional water jets moves the debris in the same direction as the cleaner is moving. Thus, the relative speed between the cleaner and the suspended dirt and debris is reduced, enabling the cleaner to move at a relatively faster rate and still clean with equivalent, or even greater efficiency than a pool cleaner that is not equipped with the directional cleaning water jet apparatus. In addition, the front and back orientations of the intake slot allow a longer time for any dirt and debris to be picked up.

[0027] Referring to FIG. 1, a first embodiment of a self-propelled robotic swimming pool cleaner implementing the present invention is shown, which includes a housing 1, an electric motor 2, a centrifugal pump 3, connecting tubes 4 and 5, jet nozzle elbows 6 and 7, filter bag holder 8, filter bag 9 and wheels 10 supporting the housing 1. The self-propelled swimming pool cleaner can include features known to the prior cleaning apparatus which are moved by the directional control of one or more water jets and valves, such as the apparatus described in U.S. Pat. No. 6,412,133 B1, the disclosure of which is incorporated herein by reference in its entirety.

[0028] As further illustrated in FIG. 2, the water jets 30, 32, are supplied by the centrifugal pump 3 and discharged by the jet nozzles 6, 7, respectively, are directed toward the dirt and debris 36 on the pool surface below the baseplate 31. The baseplate 31 is provided with an oval-shaped aperture forming an intake port 11. The intake 11 is oriented in a front and a back direction, relative to the longitudinal orientation of the jet streams 30, 32, as illustrated in FIG. 2. The streams 30, 32, are aimed at the surface below the middle of the intake 11 so that the combined water flow from the streams 30, 32, accommodates the intake 11 equally regardless of whether the cleaner moves forward or backward. In either case, the trailing half of the intake 11 is always the working half as the turbulence does not benefit the leading half. When the cleaner moves in the direction shown by arrow A, section A′ of the intake 11 does most of the cleaning. Conversely, when the cleaner moves in the direction of arrow B, section B′ of the intake 11 benefits from the turbulence to draw the suspended debris and dirt into the filter bag.

[0029] The pool cleaner of this embodiment can also be self-propelled, for example, using discharged water jets from a jet valve housing, such as the housing 22 shown in FIG. 6 as well as discharged water jets described in the incorporated U.S. Pat. No. 6,412,133 B1, employing the pressure from the discharged water jets to move the pool cleaner in selected directions controlled by water valves or other mechanisms. Alternatively, the wheels 10 can be connected to one or more drive motors for selectively moving the pool cleaner along the surface of the pool being cleaned. The drive motors can be electric or water turbine driven by pressurized water.

[0030] Although the embodiment shown in FIGS. 1–2 provides far better results than those of prior art pool cleaners, the performance and efficiency can be further improved, as will be described below.

[0031] In the second embodiment shown in FIG. 3, the one long intake opening of the intake 11 of FIG. 2 is replaced by two smaller openings 12 and 13, one of which is always closed, as by a solenoid switch or other means. Thus, the speed of the intake stream as indicated by the arrows can be doubled.

[0032] With reference to FIG. 4, there is shown yet another embodiment in which swiveling elbow jet nozzles 14 and 15 are equipped with fins 16 and 17, respectively, which automatically change the positions of the nozzles due to the force of the water, or water resistance, as the cleaner changes direction, to thereby always point to the upstream end of the intake 18. In the angular arrangement of the jet nozzles 14, 15 illustrated in FIG. 4, water is discharged at a predetermined pressure to move the debris 36 at a velocity that greatly reduces the relative speed between the debris 36 and the cleaner optimally to zero. This permits the cleaner to move at a relatively higher speed while the debris 36 is moved along in the same direction as the cleaner until the debris 36 can be drawn into the one or more intake port(s) 18 in the baseplate 31. An optional auxiliary pump 33 can also be used to boost the pressure provided by the streams 30, 32.

[0033] As shown in FIG. 5, another embodiment of the pool cleaner is provided with two pairs of directional nozzles 19 and 20 aimed at the front and rear portions of the intake port 21. A pair of solenoid activated valves (not shown) control the “on” or “off” flow condition of the nozzles 19, 20. In this embodiment, the centrifugal pump 3, the filter bag holder 8, and the filter bag 9 can be positioned external to the pool cleaner. The directional nozzles 19, 20 receive the water jet streams from an output tube 40 of the externally located centrifugal pump 3, and the filter bag 8 receives the intake water and debris 36 via the filter input tube 42. The centrifugal pump 3 is connected to an external power supply (not shown) by an electrical connector such as an electrical plug 44.

[0034] FIG. 6 is a side elevation view, partly in cross-section, of another embodiment of the invention fitted to a cleaner that is moved about the pool by water jet propulsion. In this embodiment, the jet valve housing 22 is tapped at four places 46, 48, 50, 52, shown in FIG. 7, to supply the plurality of water jet streams 54, 56 emitted from jet nozzles 58, 60, 62, 64, respectively, as best shown in FIG. 8. Those plurality of water jets function as described above to aid in the movement of dirt and debris 36 toward the intake port or ports in the baseplate 23. This embodiment operates in the same manner as the cleaner of FIG. 4, except that the change from one set of nozzles to the other set, such as the first pair 58, 62 of nozzles to the second pair 60, 64, is accomplished automatically in the jet valve housing 22 when the cleaner changes direction. This construction and method of operation eliminates the need for electronics to operate a solenoid controlled valve and provides a simple mechanism to perform the dual functions of directional control change and the flow to selected positions among the plurality of directionally oriented cleaning water jet nozzles 58, 60, 62, 64.

[0035] Referring to FIG. 9, a propeller pump 24 and a centrifugal pump 25, functioning as an impeller, are operated by the same motor 26 for use in each of the embodiments shown in FIGS. 1–5. The centrifugal pump 25 is designed to have the shape of a cone to provide the least amount of resistance to the water being pumped by the propeller pump 24. The cone-shaped propeller base 27 also provides easier transition of water going through the impeller housing 28. The cross-section of the impeller blades of the propeller pump 24 corresponds to the cross-section of an airplane wing. This configuration helps to further limit the drag which the impeller puts on the motor shaft 29.

[0036] With reference to FIG. 10 and FIG. 11 there is shown the water jet streams 30, 32 emitted from output channels 66, 68, respectively, which are connected to the connecting tubes in the various embodiments, such as the connecting tubes 4, 5 in FIG. 1. Having a centrifugal/impeller pump 25 coupled with a propeller pump 24 is also beneficial for other applications used to control the directional movement of a cleaner. For example, a hydraulic piston, which is normally operated pump powered by a small DC motor to arrest one side of moving cleaner, can be operated without the cost of the DC motor.

[0037] In FIG. 12, there is illustrated in a cross-sectional view, a manually propelled cleaner that is equipped with a bottom or baseplate 76 intake assembly which has a pair of water jet nozzles 70 permanently mounted at its opposite ends. The cleaner is also fitted with a centrifugal pump 3 that is secured to housing 1. In this embodiment water delivery tubes 4 are positioned inside the housing 1. Inner ends of said jets are slidably connected to delivery tubes 4 by couplings 74 that are also mounted inside the main housing.

[0038] Baseplate 76 intake assembly has an elongated slot 11 perpendicular to the direction of the adjacent water jets. Inside, covering said slot 11 are a pair of flaps 78 that open when suction pump 2 is on and close when power is turned off.

[0039] FIG. 13 illustrates a double pivot hinge mechanism having an “L” shaped hinge transfer member 80 connected to each flap 78. This allows the flaps to lift off said slot 11 higher at their hinged ends than would otherwise be possible. This relationship and the functioning of the hinge members 80 are further illustrated in FIG. 14 where the flaps are shown in closed position. In the embodiment of FIGS. 12–15, the cleaner is manually propelled by handle 71.

[0040] In the interior cross-sectional view of FIG. 15, the flaps 78 are shown in the closed position, each flap supported by a single hinge member 80. As will be understood by one of ordinary skill in the art, two or more hinge members 80 can be employed should the size of the intake 11 and/or flaps 78 be increased. The pivot means 82 permit the flaps to move easily in response to the water pressure during flow to settle in the closed position.

[0041] FIG. 16 is a bottom view of another water jet assisted cleaner that is equipped with a conventional baseplate intake assembly in which the major axis of the intake slot is parallel to the direction of their respective associated water jets. Although the direction of said slots are not in an optimum angle (front and back), the cleaning efficiency is still greatly increased when water jets are introduced to assist in raising the dirt and debris into suspension below the moving cleaner.

[0042] FIG. 17 is a bottom view of yet another cleaner in which the intake slot is perpendicular to the movement of the cleaner and a pair of manifolds 100 are located parallel to said intake slot 11 in the front and back ends of the cleaner to provide multiple jet streams through a number of small water jet discharge openings 102 along the length of said manifold, aiming slightly down, but mainly toward said intake slot 11. In this embodiment, the single intake slot 11 extends substantially across the baseplate. A pair of valves 104 control the water flow from centrifugal pump 3 so that only the trailing manifold is activated, sweeping the debris forward, along with the moving cleaner, until it is picked up with water drawn into the intake slot 11. In a preferred embodiment, each of the discharge openings 102 is provided with a low friction fitting to minimize the back pressure in the system and enhance the turbulent effect of the water stream to suspend dirt and debris.

[0043] An additional benefit of this arrangement is that the cleaner can clean very close to a sharp-cornered vertical pool wall. Although the plurality of water jet streams trail the moving cleaner, when said cleaner stops at the wall and reverses its direction, the trailing manifold begins sweeping the swimming pool floor close to the vertical wall.

[0044] In another embodiment of the manifolds of FIG. 17 (not shown), of the control valves, are omitted, leaving open the flow path to both delivery tubes and manifolds. Although the front water jets will be sweeping the debris backwards against the directional movement of cleaner, the rear water jets sweeping forward trap debris under intake port 11 until it is picked up.

[0045] Referring to the embodiment of FIG. 18, valves controlling the water jet manifolds are replaced by solenoids 110 which automatically turn a pair of swiveling manifolds 100 so that the leading manifold's water jets 102 are aimed substantially downward, stirring up the debris, while the trailing manifold's water jets are aimed substantially forward, sweeping the debris along with the moving cleaner. Both manifolds are open at all times.

[0046] With reference to FIG. 19, there is illustrated an embodiment in which both manifolds 100 are in a fixed position with their water jets aimed substantially downward. Although this fixed positioning of the water jets may not be as efficient in cleaning as those described above, it will outperform prior art cleaners that are not assisted by water jets. The elimination of electronics components that are necessary to operate solenoids and/or other automatic switching mechanisms makes this embodiment of the invention particularly cost-effective to produce.

[0047] There are other benefits and advantages from the embodiments illustrated and described above that will be apparent to those skilled in the art.