Automatically Extensible And Retractable Swimming Pool Cleaner With Housing In Bond Beam

Abstract

A pool cleaner of the type utilizing scouring jet hoses automatically extensible from tubular housings when subjected to pressurized water flow, and retractable in response to reversal from pressure to suction, wherein the housings are contained in the bond beam of the pool and connected to the pool by short radius bends, the rear ends of the hoses being pistons which are pivotally attached thereto so as to traverse said bends without binding therein.

Description

BACKGROUND OF THE INVENTION

Automatically extensible and retractable jet hose type cleaners have been known and in use for a number of years past, and are disclosed in the following patents:

Whittaker U.S. Pat. No. 3,278,949

Howard et al U.S. Pat. No. 3,530,511

The installation of such cleaning apparatus has required excavation and placement of the housing tubes externally of the pool wall, regardless of whether the tubes ere extended in a straight line radially outwardly from the pool, or connected to the pool by 90.degree. bends, with the bodies of the tubes extending parallel to the pool wall. In such installations, it has hitherto been found necessary to utilize a radius of two feet or more in the bends in order to allow the rear ends of the hoses, with their attached pistons, to freely slide around the bends. This locates the bodies of the housing tubes in the ground, outside the pool wall, requiring excavation around the outside of the pool in order to install the housing tubes.

OBJECTS OF THE INVENTION

The invention provides for installation of the housing tubes wholly within the bond beam which defines the rim of the pool, thus making it possible to install the plumbing for the cleaning apparatus without the necessity for excavation externally of the pool wall.

Objects of the invention are:

1. to avoid excavation outside the pool wall;

2. to encase the housing tubes in cement so as to protect them from corrosion arising from soil electrolysis;

3. to avoid the necessity for extra space outside the pool perimeter for installation of the cleaning apparatus, where the area available for pool construction is limited.

DESCRIPTION

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

FIG. 1 is a fragmentary horizontal sectional view of a swimming pool and cleaner installation embodying the invention;

FIG. 2 is a vertical sectional view of the same taken on line 2--2 of FIG. 1;

FIG. 3 is a detailed axial sectional view of a portion of FIG. 2, on an enlarged scale; and

FIG. 4 is a cross-sectional view of the piston, taken on the line 4--4 of FIG. 3.

Referring now to the drawing in detail, I have shown therein, as an example of one form in which the invention may be embodied, a swimming pool including a lateral wall 10 which is thickened at its upper extremity to provide a bond beam 11 defining the pool rim, a body of water 12 being contained within the wall 10.

The cleaning apparatus comprises a plurality of hose housings 15 extending longitudinally in bond beam 11 and each having at one end a 90.degree. bend 16 terminating in a receptacle 17 having an open end flush with the inner surface of bond beam 11 and communicating with the body of water 12. Each housing 15 contains a respective cleaning hose 20 which extends through a bearing bushing 21 in the open end of receptacle 17 and is adapted to be projected therethrough into the pool for cleaning action. On the rear end of hose 20 is a piston 22 adapted to move longitudinally in housing 15 in response to water pressure or suction applied thereto respectively by a pressure source P (discharge of pool circulation pump) or suction source S (inlet of pump or a separate suction unit such as the ejector of Howard et al U.S. Pat. No. 3,530,511). When circulation controls V (such as disclosed in said Howard et al patent) are actuated to establish a pressurized flow of water from source P against piston 22, a positive differential of pressure thus established against the piston 22 over the pressure in pool water 12, will become effective to project the cleaning hose 15 into the pool until it is arrested by abutment of piston 22 against bearing bushing 21, whereupon the pressurized flow will pass through hose 15 and against the internal surface of the pool with a scouring action for the duration of a cleaning cycle ending when the controls are actuated to cut off the pressurized flow and apply suction (negative differential) from source S to the housing 15 behind the piston 22. A check valve 25 inside the piston 22 will then close to prevent reverse flow through hose 20 and to cause the full pressure differential of pool water 12 over the sub-atmospheric pressure at suction source S, to be applied to piston 22 to withdraw the hose 15 into housing 15.

In the terminal stage of hose projection and the initial stage of hose withdrawal, piston 22 will travel freely around the bend 16 without binding therein. This is made possible by a ball and socket pivotal connection between piston 22 and hose 20. Piston 22 comprises a barrel-shaped annular body 30 having at one end an internal collar 31 defining an opening through which is extended a hose nipple 32 which is secured in the end of hose 20. Collar 31 provides an annular seat against which a frusto-conical shoulder 33 on a head 34 on the end of nipple 32, is adapted to seat when the piston is subjected to pressure flow, thereby to prevent any substantial leakage around the hose nipple from within piston 22. Piston body 30 is barrel shaped, having an external surface consisting of two frusto conical surfaces tapering to minimum diameter at the respective ends of the piston and intersecting at or near the mid-length of the piston to define a peripheral land 35 of maximum diameter and of minimum axial width, which is fitted in the bore of housing 15, 16 with just sufficient clearance to permit the piston to freely slide in the housing in response to pressure differentials in the water flow. The tapering of the external surface of the piston toward its respective ends makes it possible for the piston to pivot around the nipple head 34 in order to follow the short radius curvature of housing bend 16, without binding or substantial increase in resistance to its sliding movement. Frusto-conical shoulder 34 is pivotally slidable against the seat provided by the edge of collar 31, so as to allow the pivotal movement of the piston while maintaining a substantial seal between the piston 22 and nipple 32.

Threaded into the end of piston body 30 in opposed relation to nipple head 32, is a valve seat ring 37 defining an inlet port 38 and a frusto-conical valve seat 39. Ball valve 25 is retained between valve seat 39 and an annular array of fingers 41 projecting axially from nipple head 34, the fingers 41 being spaced circumferentially to provide passages 42 for flow of water past the ball 40 into hose 20 during a cleaning cycle, and providing abutments to hold the ball 40 in open relation to nipple head 34.

In operation of the apparatus, when the controls are actuated to provide a pressure flow from source P into housing 15, the pressure differential will be effective against the area of piston 22 outwardly of the bore of nipple 32, to project the hose 20 from the housing 15, 16 into the pool, wherein it will droop into contact with the bottom of the pool as indicated in FIGS. 1 and 2. Upon contact of piston 22 with bushing 21 it will seal the receptacle 17 against any substantial leakage from the housing around the hose 20 into the pool, so that substantially the full pressure flow will pass through the hose and be discharged from its forward end to provide a scouring jet which will scrub sedimentary particles from the pool bottom and propel them into suspension in the water 12 to be drawn off through the pool's skimmer.

At the end of a cleaning cycle, upon reversal of the controls so as to disconnect the housing 15 from pressure source P and connect it to suction source S, sub-atmospheric pressure will be established in housing 15, 16 and atmospheric pressure against the surface of water 12 will then establish a pressure differential acting against the forward side of piston 22 through bearing bushing 21. At the same time, water pressure in hose 20 will act against ball valve 25 to move it into seating engagement with seat 39 to close the rear end of hose 20, preventing reverse flow through the hose and causing the pressure differential to be effective against the full cross-sectional area of piston 22.

Claims

I claim:

1. In a swimming pool having a bond beam defining its rim and having means for circulating a pressure flow of water and for providing a suction source, in combination:

a tubular housing including a body portion extending longitudinally of said bond beam and a bend connecting a forward end of said housing to the pool interior beneath its water level;

a clearing hose normally housed in said housing;

a piston pivotally coupled to the rear end of said hose and slidable in said housing in response to pressure differentials therein, so as to project and retract said hose in response to positive and negative differentials in said housing respectively, pivotal movement of said piston relative to said hose facilitating travel of the piston through said bend;

said piston having a port through which water can flow from said housing through said hose to provide a cleaning jet in response to positive pressure in said housing.

2. The combination defined in claim 1;

said piston having maximum diameter intermediate its ends, with a periphery fitted in said housing for response to pressure differentials, and tapering from said maximum diameter to minimum diameters at its respective ends, to facilitate travel of the piston through said bend.

3. The combination defined in claim 2;

said piston having dual frusto-conical external surfaces intersecting at their major diameter to provide said periphery fitted in said housing.

4. The combination defined in claim 1;

and a check valve in said piston operable to open for flow from the housing into the hose and to close to prevent reverse flow, whereby to amplify the negative dif-ferential for retraction of the hose.

5. The combination defined in claim 4;

said check valve comprising a ball;

a valve seat ring secured in the rear end of said piston, said ring defining said port and having a frusto-conical internal surface flaring forwardly to provide a valve seat for engagement by said valve ball;

and circumferentially spaced abutment fingers in the forward end of the piston, operable to hold the ball in an open position permitting flow through the piston into the hose.

6. The combination defined in claim 1;

said piston comprising an annular body having a front end opening defined by an internal collar providing an annular seat;

a hose nipple secured in the rear end of said hose, extending through said opening and having at its rear end an annular head with a frusto-conical shoulder engaged against said seat to provide the pivotal coupling between said hose and said piston.

7. The combination defined in claim 6;

said annular body being barrel shaped with a periphery of maximum diameter intermediate said ends, fitted in said housing to provide differential pressure response and tapering to minimum diameters at its ends to facilitate tilting within said housing for free travel through said bend.

8. The combination defined in claim 7, further including:

a valve comprising a valve seat ring secured in the rear end of said annular body and providing a forwardly facing annular valve seat;

and a ball caged between said valve seat and said nipple head and adapted to engage said seat to prevent rearward flow from said hose into said housing.

9. The combination defined in claim 8;

said nipple head having circumferentially spaced abutment fingers for engagement by said ball to hold it in an open position permitting flow from said port between said fingers into said hose in response to positive pressure differential in said housing.