Valve arrangement for an automatic pool cleaner

#The invention relates to automatic pool cleaners of the type described by Australian Patents 490972 and 505209, both of which are included herein by reference. In particular, the invention relates to arrangements and methods of operation, which may be implemented so as to reduce the size of an automatic pool cleaner without detrimentally affecting functionality.

#Pool cleaners of the type described above substantially comprise a seal arrangement, sealing a pool surface to a suction zone in fluid communication with a valve chamber. Exiting from said valve chamber are two parallel tubes/passages meeting at a flow attenuation element, which is then connected to a flexible hose. Within said valve chamber there exists a flap valve oscillating between the outlet to each of the tubes. As water flows into the valve chamber, water is drawn up one tube/passage, the mass flow of said water drawing the flap valve over the exit closing off the first tube and creating a water hammer impulse due to the rapid closure. Water is then diverted to the second tube/passage, again drawing the flap valve towards the exit leading to the second tube/passage and, consequently, closing the second tube and diverting water to the first. Therefore, the flap valve oscillates from the first tube/passage to the second tube/passage creating a series of water hammer impulses, which drive the pool cleaner across the pool floor and walls.

#In order to create the desired oscillation frequency and momentum driving the pool cleaner, it has been found that a certain length of tube is desirable. However, for certain applications, and for general economic reasons, it is sometimes desirable to have a pool cleaner with tubes significantly shorter. Because of the complexity of the system, a shortening of the tubes or reduction in internal diameter (ID) does not necessarily equate to an equivalent reduction in size of other components nor the efficiency or effectiveness of the pool cleaner operation due to, inter alia, the reduced mass flow of water oscillating in each tube.

#It will be convenient to further described the present invention with respect to the accompanying drawings, which illustrate a possible arrangement of the invention. Other arrangements of the invention are possible and, consequently, the particularity of the accompanying drawings is not to b understood as superseding the generality of the preceding description of the invention.

#FIG. 1 is an elevation view of the automatic pool cleaner according to the present invention.

#FIG. 2 is a close-up elevation view of the valve chamber of the automatic pool cleaner of FIG. 1.

#FIG. 1 shows an automatic pool cleaner 1 substantially as described in Australian Patent Nos. 490972 and 505209. In particular, the automatic pool cleaner 1 shows parallel tubes 5 and 6 projecting from, and in fluid communication with, a valve chamber 4 in which is located a flap valve 7. The automatic pool cleaner 1 further includes a sealing arrangement 2 into which is drawn a flow of water, which passes through orifice 3 into the valve chamber 4. Water is then directed into one of the tubes 5 or 6 as determined by the position of the flap valve 7 at any particular stage. Flap valve 7 is adapted to move within the valve chamber 4 in a single degree of freedom as shown in FIG. 2.

#As shown in the close-up view of the valve chamber 4 in FIG. 2, the flap valve 7 pivots about point 7a in an arcuate fashion 9 such that at its extreme points of travel, the flap valve 7 will close off either of the apertures 5a or-6a. As the water flow 12 travels up tube 5, the mass flow of water will tend to deflect the flap valve 7 towards aperture 6a until it is eventually blocked. This will then direct a greater water flow through aperture 5a and into tube 5 and, consequently, draw the flap valve back towards the aperture 5a until it is closed off. The motion of the flap valve 7 continues in the oscillatory manner 9 whilst water is drawn up through the automatic pool cleaner 1.

#The automatic pool cleaner 1 of FIG. 1 being of conventional size and orientation has tubes 5 and 6 of standard length each having the capacity of holding a substantial volume of water. The mass flow of the water in each of these tubes represents a significant force and so on commencement of the operation of the automatic pool cleaner 1, the flap valve initiates movement immediately. However, because certain applications require a considerably smaller machine and, therefore, tubes/passages 5 and 6 being considerably shorter or of smaller ID, the mass flow of water through said tubes 5 and 6 will be less and so the applied forces to the flap valve 7 may not initiate the oscillatory action 9 without the intervention of an operator.