Pre-filter for swimming pool installations

Abstract: Comprises a housing which includes a basket (5) closed with a cover (29) and fitted to a suction/force pump (16), whose motor is cooled by the water sucked by the pump. It is characterised in that this fitting is by means of an independent yoke (11) whose face abutting the pump is provied with a tubular trunnion (19) which comprises various longitudinal channels (26) to let in the water for cooling the motor (25) of the pump (16), and that the water outlet (9) is situated on a cavity (8) laterally adjacent to the pre-filter housing (1), the yoke (11) being attached and fixed to the mouth (10) of said cavity (8). It is further characterised in that cover consist of two parts (29 and 30).

Description: Several versions of this type of unit are already known wherein pre-filters generally consist of a housing and cover laterally fitted to a suction/force pump and provided inside with a basket-shaped grille, the housing comprising a water inlet and lower down an opposing outlet for the filtered water sucked by the pump. A pre-filter of this kind is described in the US Patent 3,252,575. However, the pre-filters which have been used until now have a number of problems, of which it is worth mentioning the poor suction performance of the attached pump, imperfect filtration, difficulty in opening (due to depression effects) for cleaning, and vibrations transmitted to the ground where the pre-filter/pump assembly is fitted. These pre-filters are fitted to a pump whose motor is cooled by the circulation of water from the same pre-filter wherefore the housing is fixed to the pump motor by means of an intermediate yoke consisting of an element in which the pump wheel is located. On the face which abuts against the pre-filter housing, this circular yoke element is provided with a cavity in which the pump wheel is located, whilst on the opposite face the yoke element is provided with a central tubular trunnion in which the pump axle is located by means of a suitable bushing. The present invention is characterised by the presence of various longitudinal channels distributed about the circumference of said tubular trunnion which channels let go through them the water for cooling the pump motor, the water being driven towards it. The invention is further characterised in that a cavity provided with a water delivery mouth is arranged adjacent to the pre-filter housing, the yoke element being fitted to the mouth of said cavity . The cover consists of two elements, the cover itself and a screw collar by means of which the cover is secured against the upper mouth of the pre-filter housing, and with which arrangement the depression problem in opening the cover is solved since the screw collar is removed first and then the cover can be lifted easily. A further embodiment of this invention is the pre-filter/pump assembly which is fixed to a base by means of elastic pads which eliminate the transmission of all vibration to the ground. A further embodiment is the handle of the basket-shaped grille which forms an integral part thereof. These and other embodiments will become more apparent in the Detailed Description, taken together with the three accompanying drawings which show a practical embodiment which represents only one non-limiting example of the scope of the present invention. In the drawings: Figure 1 shows a vertical section of the pre-filter housing and the yoke element. Figure 2 represents a frontal view of the yoke element as seen from the face which abuts against the pre-filter housing. Figure 3 illustrates, again in vertical section, the assembled pre-filter/pump arrangement. Figures 4 and 5 show respectively a vertical section and a half plan view of the pre-filter housing with the cover fitted. Figure 6 is a perspective view showing details of the handle of the basket-shaped grille. As the drawings show, the pre-filter consists of a truncated, slightly conically shaped housing 1 which forms an upper mouth receptacle 2 with an external thread 3 for the cover. The housing is provided with an upper, radially oriented water inlet 4 , inside is fitted a basket-shaped grille 5 and at the bottom of the housing is a radially oriented purge orifice. Opposing and below the water inlet 4 , the housing is provided with an outlet 7 for the filtered water. This outlet leads to a lateral cavity 8 adjacent to the housing 1 at the top of which is located another outlet 9 through which the water passes to the outside. A yoke 11 is attached and fixed to the mouth 10 of the lateral cavity 8 of the housing 1 and comprises a circular element 12 whose face 13 abuts against the housing 1 to form a peripherally threaded cavity 14 in which the pump wheel 15 of the pump 16 is located. The cavity 8 and the yoke element 12 are fixed together by means of their respective peripheral rebates 17 and 18 . On the face oriented away from the cavity 14 , the yoke element 12 is provided with a tubular trunnion 19 in which one of the ends of the pump axle 20 is located by means of a bushing 21 , wherein the axle is tubular and along its length runs the conduit 22 and wherein said face of the yoke element also comprises a peripheral rebate 23 for fitting to the housing 24 of the pump motor 25 . The aforementioned tubular trunnion 19 is provided with a number of longitudinal channels 26 distributed about its circumference and through which the water for cooling the motor 25 enters. The water is driven towards the motor, after cooling which it passes along the conduit 22 of the pump axle to arrive at the cavity 14 where the pump wheel is located, passing then to the outlet 9 in the pre-filter housing. The pre-filter/pump assembly is fixed to the ground by means of an interposed base 27 which supports it by means of elastic pads 28 . A cover 29 is fitted to the upper mouth of the pre-filter housing 1 by means of a screw collar 30 where said cover is advantageously transparent and has a diametric external protrusion 31 which may, if desired, include a depression purge orifice which can be closed by means of a stopper. In order to fit and secure the cover to the housing 1 , the periphery of the cover is provided with an angular section and an underlying rim 32 which fits into the internal periphery of the mouth of said housing, and an external rim 33 which is seated on top of said mouth with an interposed o-ring seal 34 . The cover is secured by means of an internal flange 35 on the upper edge of the screw collar wherein said flange presses against said rim 33 of the cover. The basket-shaped grille 5 is stabilised within the housing 1 by the pressure exerted from above by a ring-shaped protrusion 36 provided on the inside of the cover 29 , wherein the pressure is elastically maintained by means of the transverse handle 37 which forms a single piece with basket-shaped grille. The handle consists of two flexible strips 38 and 39 which begin at diametrically opposed points on the port of the basket-shaped grille and whose two free ends are fixed together by introducing a T-shaped projection 40 on one of the strips into an eye 41 in the other strip.

Claims: A pump unit and pre-filter for swimming pool installations which pre-filter consists of a housing comprising a basket-shaped grille (5), closed with a cover (29) and laterally fitted to a suction/force pump (16), the motor of which is cooled by the water, characterised in that this fitting is by means of an independent yoke (11) whose face abutting the pump is provided with a tubular trunnion (19) which comprises various longitudinal channels (26) which let go through them the water for cooling the motor (25) of the pump (16), and that a cavity (8) provided with a water delivery mouth (9) has been arranged, adjacent to the pre-filter housing (1), the yoke (11) being attached and fixed to the mouth (10) of said cavity (8). A pump unit and pre-filter for swimming pool installations according to claim 1 characterised in that the cover (29) consists of two elements, the cover itself and a screw collar (30) by means of which the cover is secured to the upper mouth (2) of the pre-filter housing (1) wherefore the periphery of said cover (29) has an angular section (32-33) which fits into the internal periphery of said mouth (2) and which is supported by it where it is forced by an internal flange (35) on the upper edge of the screw collar (30). A pump unit and pre-filter for swimming pool installations according to claim 1 wherein the pre-filter is provided on a base (27) together with the pump (16) by means of interposed elastic pads (28) provided for fitting the pre-filter housing (1) to the base (27) and supporting the yoke (11) thereon. A pump unit and pre-filter for swimming pool installations according to claim 1 wherein the basket-shaped grille (5) comprises, and forms a single piece with, a handle (37) consisting of two flexible strips (38,39) which begin at diametrically opposed points on the mouth of the basket-shaped grille and whose free ends are fixed together (49,41).

Inventors: GARRIGOS RUIZ ROBERT, GARRIGOS RUIZ, ROBERT
Applicants: DOLL SA, DOLL, S.A.
Application year: 1992
Main classification: E04H4
IPC codes: E04H4, F04D13