Automatically extensible and retractable suction and scouring action pool cleaner

BACKGROUND OF THE INVENTION

Cleaning apparatus embodying automatically extensible and retractable scouring jet hoses without any suction means associated therewith, is disclosed in my copending application Ser. No. 782,357, filed Dec. 9, 1968, now Pat. No. 3,530,511, issued Sept. 29, 1970, and in Whitaker Pat. No. 3,278,949, issued Oct. 18, 1966. A cleaning sweep embodying a scouring jet hose inside a suction hose for combined jet scouring and suction cleaning operation, is disclosed in Gelinas Pat. No. 3,433,237, issued Mar. 18, 1969.

SUMMARY OF THE INVENTION

This invention provides a combination of a double-hose sweep with combined jet scouring and suction cleaning action; an under-the-deck housing tube into which the sweep is normally withdrawn from the pool; a water circulating system including a conventional circulating pump and a separate suction generator such as an Aqua-Jet eductor; a suction connection from the pump inlet to a suction aperture in the side of the suction hose near its rear end; and valving means to selectively apply the pumj delivery to the rear end of the sweep to extend it, to then apply pump inlet suction to the suction hose aperture while continuing to apply pump delivery to the rear end of the sweep for combined vacuum cleaning and scouring sweep action, to then apply auxiliary suction to the rear end of the sweep for retracting it while cutting off the jet flow, and finally to isolate the sweep from the flow circuit while establishing a normal filtering flow. A specific object of the invention is to combine all of these several stages of operation. Another object is to shift from one stage to another by selective opening and closing of a plurality of valves. Another object is to provide for automatic application of suction to the rear end of the suction hose, internally thereof, for cleaning action, as the result of arrival thereof at a suction connection at the end of a projection movement of the sweep. Another object is to provide a source of suction, independent of the pump inlet suction, and to apply it to the rear end of the sweep externally thereof for retracting action, without communicating such suction to the interior of the hose.

Other objects will become apparent in the following specifications and appended drawings, in which:

FIG. 1 is a schematic diagram of a pool equipped with the automatic cleaning apparatus of my invention;

FIG. 2 is a detail fragmentary sectional view of the forward end of the sweep housing and of the rear end of the cleaning sweep, in its projected position for cleaning operation; and

FIG. 3 is a fragmentary sectional view of the sweep housing, showing modifications of several of its features.

DESCRIPTION

Referring now to the drawing in detail, we have shown therein, as an example of one form in which the invention may be embodied, a system for automatically cleaning a pool A by a plurality of flexible sweeps B each having combined jet action for scouring sediment from the pool bottom, and suction pickup of the loosened sediment, in response to delivery of water from the outlet of the pool’s circulating pump P through a delivery line L and application of the pump’s inlet suction through a suction line LI. These lines are correlated with the pool’s normal circulating and filtering system C including the pump P, a normal suction line L2 from a skimmer S to the pump inlet, a filter F and a normal pool return line L3 extending from the filter to the pool. Sweeps B are normally housed in tubular housings D which have rear end fittings 30 connected to the pump discharge through line L and through a valve V, for projecting the sweeps when this valve is open, and which have lateral suction ports connected to suction line LI (and thence to the pump inlet) through a valve VI.

The system further includes an eductor E, connected to the pump discharge through a pressure line L4, the discharge being directed through the eductor to an auxiliary pool return line R when a valve V4 in the eductor is open. The eductor may be of a type known commercially as the Aqua Jet, and includes a suction (e.g. venturi) throat having a suction inlet connected to a suction line L5 which in turn communicates with the rear ends of housings D through a check valve V5 which permits suction flow from the rear ends of housings D into eductor E and thence to return line R, but prevents flow from pressure line L4 to the housings D. Optionally a 3-way valve OV may provide a controllable junction between the pump discharge (delivered through filter F) and the alternate lines L3 and L4. Gate valves V2 and V3, selectively operable to full open, full closed or intermediate throttling positions, are interposed in the normal pump suction line L2 and the normal pool return line L3 respectively.

The eductor E functions, with an aspirating action, to develop suction in the sweep-retractor suction line L5 which is connected to the housing line L so as to apply suction to the rear ends of housings D. The differential of atmospheric pressure against the surface of the water W in pool A (assisted by the hydrostatic pressure of the head from the pool surface down to the level of cylinders D) over the reduced pressure in cylinders D, will be effective to draw sweeps B into their respective housing cylinders, clearing the pool interior.

Each of the sweeps B (FIG. 2) comprises an inner jet tube 5 and an outer suction hose 6 telescoped over the tube 5 and carrying it. The rear ends of tube 5 and hose 6 are secured to and connected by an assembly G comprising generally a sleeve 7 and a check valve V6 secured in the rear end of sleeve 7. Sleeve 7 has a bevelled forward end providing an annular shoulder which seats on a bevelled seat in a bearing bushing 8 to seal the rear end of hose 6 to the forward end of housing D to prevent loss of suction therein, and to limit the forward projection of sweep B at the fully projected position shown in FIG. 2. In this projected position, one or more suction ports 9 are in communication with a suction throat 10 of cylinder D, embodied in the lateral arm of a T fitting 11 which provides the connection to suction line LI from the main tube section 12 of cylinder D, which is secured in one end of T 11. The other end of T 11 is coupled, by

3,575,729 a nipple 13, to an end collar 14 in which bearing bushing 8 is anchored. Collar 14 is located in the wall 15 of pool A so as to position the bearing bushing 8 flush with the internal surface of the pool thus providing, at the forward end of cylinder D, a mouth in communication with the body of water W within the pool.

Bushing 8 is of a material having a suitable anti-friction characteristic and sufficiently yieldable under pressure to form a good seal with the end of sleeve 7. Tetrafluoroethylene (Teflon) or an equivalent plastic material, is satisfactory for this purpose.

The forward end of each sweep B (FIG. 1) is provided with a suction head 17 communicating with suction hose 6, to apply the suction thereof to the surrounding water, as indicated by arrows 19, and nozzle 18 (which may simply be the projecting end of tube 5) delivers the scouring jet 20 against the pool surface. In general, the sweep B may be similar to the pool-cleaning sweep disclosed in the above identified Gelinas Pat. No. 3,433,237, including bearing collars 21 for regulating its undulating movements along the pool bottom.

The rear end of suction hose 6 is anchored and sealed in the forward end of sleeve 7. The rear end of jet tube 5 projects beyond the end of hose 6 and through a suction chamber 16 defined within sleeve 7, and is coupled by means of a threaded hose nipple 24 to a valve casing 25 having a valve seat ring 26 cooperating therewith to enclose a ball valve 27. Ring 26 is provided with a frustoconical valve seat 28 against which valve 27 will seat to check back-flow through tube 5 when suction is applied to the rear end of sweep B within housing tube 12 to retract the sweep. When pump discharge flow is delivered to the rear end of housing D, the pressure thereof will be applied to valve 27 through an orifice 29 defined in valve seat ring 26, and will unseat the valve 27, which will be held away from the mouth of jet tube fitting 24 by projections 23 in the bottom of valve casing 25 (e.g. on the rear end of fitting 24). Thus the pump discharge flow will pass through fitting 24 and jet tube 5 to produce the scouring jet 20 delivered against the internal surface of the pool. At the same time, suction in line LI will be applied through ports 9 in sleeve 7 to the interior of suction hose 6 as to effect a suction-cleaning operation of head 17 in the area of scouring action of jet 20 so as to draw through the hose 6 and line LI into pump P for discharge into filter F, the cloud of sediment particles stirred up by jet 20. During this operation, the pressure of the pump discharge against the closed rear end of sweep B (at and around valve seat ring 26) will be equal to or more than the suction applied to hose 6, and hence the sweep B will remain extended, with no tendency to be drawn back into cylinder D.

The main tubes 12 of housings D may extend into the ground beneath the pool deck externally of the pool, as more fully disclosed in my aforesaid pending application Serial No. 782,357, and may be straight or broadly curved along their longitudinal axes, as circumstances may require.

Housing D have rear ends defined by end fittings 30 connecting them to water pipe lines L.

OPERATION

Cleaning

The cleaning stage of operation will be understood from the foregoing description. Assuming that optional valve OV is omitted from the system, and that a T junction between filter F and lines L3 and L4 exists at its location, the cleaning stage is established by the following valve positions:

V --------------------------------------- Open

VI ------------------------------------- Open

V2 -------------------------------------Throttle

V3 --------------------------------------Throttle

V4 ------------------------------------- Closed

Thus jet flow will be applied through open valve V, pump inlet suction will be applied through open valve VI, normal skimming flow to pump P will be throttled at valve V2 without shutting it off so completely as to cause pump P to cavitate, normal pool return flow will be throttled at valve V3 without unduly raising the back pressure at the pump outlet (likewise inhibiting cavitation) and operation of eductor E will be suppressed at closed valve V4.

The sealing of the forward end of sleeve 7 to the forward end of housing D through its pressure contact with bearing collar 8 will prevent loss of suction around the exterior of hose 6 and sleeve 7, and will concentrate the suction internally of the hose.

Retract

From the cleaning stage, a sweep-retracting stage is established by changing the valves to the following positions:

V___________________________________________Closed

VI ______________________________________Closed

V2 __________________________________________ Open

V3 ______________________________________Closed

V4 _______________________________________ Open

Lines L and LI being shut off at valves V and VI, the pump discharge and inlet suction will be cut off from the rear end of housing tube 12 and the suction throat 10 of cylinder D, and eductor suction will be applied to the rear end of housing tube 12 to retract the sweep into cylinder D. Retracting movement of the sweep Will be terminated by contact of its rear end (e.g. head of valve seat ring 26) with a rear end member 30. When suction is thus applied, check valve V6 will close so as to avoid loss of suction by flow through tube 5 and to concentrate the full force of the suction against the rear end of sweep B.

Normal filtering operation

With the sweeps fully retracted, normal filtering operation can be established by changing the valves to the following positions:

V ---------------------------------------Closed

VI ---------------------------------------Closed

V2 ------------------------------------- Open

V3 -------------------------------------- Open

V4 --------------------------------------Closed

With normal suction (skimmer) line L2 and normal return line L3 fully open and with flow to the eductor E and cylinders D cut off by closed valves V4, V and VI, the sweep actuating units will be rendered inoperative and full flow will be directed through the normal filtering circuit.

EXTEND

To extend the sweeps into cleaning positions after a period of normal filtering operation, the valves are changed to the following positions:

V--------------------------------------- Open

VI --------------------------------------Closed

V2-------------------------------------- Open

V3 --------------------------------------Closed

V4 --------------------------------------Closed

Full pump discharge will then be directed into the rear ends of housings D through open line L (normal return line L3 being closed). The pump pressure against the closed annular areas of the rear ends of the sweeps (i.e. of valves V6 around valve ports 29) will project the sweeps into the pool. Unrestricted suction flow to the pump inlet will be transmitted by skimmer suction line L2, and pump inlet suction will be cut off from the suction throats 10 of housing D.

The extending movement will be terminated by contact of the forward end of sleeve 7 with bearing collar 8. The

3,575,729 cleaning operation can then be made effective by changing the valves to their cleaning setting given above.

FIG. 3 discloses a preferred embodiment of the rear end structure of the sweeps B, in which the hose 6 has a portion 6A continued to the rear end of the sweep and attached directly to the valve V6, and the suction ports 9 are formed directly in hose 6. A stop ring 7A is secured to hose 6 in encircling relation, to engage bearing bushing 8 to position the rear end structure of the sweep at the forward limit of projecting movement, with suction ports 9 operatively registered with the suction throat of T fitting 11. A gasket ring 31 is secured between the flange of valve seat ring 26 and valve casing 25, to prevent bypass of water under pressure from line L around valve V6 to the suction throat of fitting 11. The flexible hose section 6A allows the rear end of the hose to bend on a radius as small as three feet to enter the housing tube 12 where it may be required to have an arcuate bend to meet space requirements under the pool deck.