US3670893A - Control arrangement for a swimming pool filter - Google Patents

Control arrangement for a swimming pool filter Download PDF

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Publication number
US3670893A
US3670893A US112315A US3670893DA US3670893A US 3670893 A US3670893 A US 3670893A US 112315 A US112315 A US 112315A US 3670893D A US3670893D A US 3670893DA US 3670893 A US3670893 A US 3670893A
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Prior art keywords
valves
valve
wheel
filter
pump
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Expired - Lifetime
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US112315A
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English (en)
Inventor
Volker Seid
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Cillichemie Ernst Vogelmann GmbH and Co
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Cillichemie Ernst Vogelmann GmbH and Co
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D37/00—Processes of filtration
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
    • E04H4/00—Swimming or splash baths or pools
    • E04H4/12—Devices or arrangements for circulating water, i.e. devices for removal of polluted water, cleaning baths or for water treatment
    • E04H4/1209—Treatment of water for swimming pools
    • E04H4/1245—Recirculating pumps for swimming pool water

Definitions

  • the control arrangement for a swimming pool filter includes two pairs of control valves, the discharge port of the first valve in each pair being coupled to the intake port of the second valve.
  • the intake ports of the first valves are connected by a high-pressure conduit to the output end of the filter pump whose input end draws water from the pool.
  • Two low-pressure conduits connect the discharge ports of the second valves to the pool and to a waste line respectively.
  • the filter is connected by by-pass lines to the coupled ports between the valves in each pair.
  • a single operating mechanism is connected to all valves and operates the same in timed sequence in which the valves direct water flow from the pump either through the filter in a first direction to the pool, or through the filter in the opposite direction to a waste line, or ultimately directly from the pool to the waste line.
  • This invention relates to a control arrangement for a swimming pool and particularly to an arrangement which normally causes water from the pool to be filtered and returned to the pool, but uses water from the pool from time to time for backwashing the filter and discards the resulting slurry.
  • a control arrangement which includes two pairs of control valves having each an intake port and a discharge port.
  • the discharge port of the first valve in each pair is coupled to the intake port of the second valve.
  • a high-pressure conduit is provided for connecting the intake ports of both first valves to the discharge end of a pump.
  • Two low-pressure conduits may connect the discharge ports of the two second valves to a swimming pool from which the pump draws water and to a waste line respectively.
  • Two by-pass conduits are arranged for connecting the filter for the pool between the couplings in the two valve pairs respectively.
  • valves are connected to a single operating device which operates the valves in a timed sequence in which the valves, when connected by the conduits to the pump, the pool, the waste line, and the filter, direct flow of water from the pump in a first stage in one direction through the filter and to the pool, and in a second stage through the filter in the p posite direction and to the waste line. If so desired, pumped water may be led in a third stage from the pump directly to the waste line.
  • FIG. I is a flow diagram of a swimming pool equipped with a filter, a circulating pump, and a control arrangement of the invention in a first stage of operation;
  • FIGS. la and lb diagrammatically illustrate the apparatus of FIG. 1 in second and third operating stages respectively;
  • FIG. 2 illustrates the control valve assembly of the apparatus of FIG. 1 in elevation, and partly in section;
  • FIG. 3 shows the pilot valve assembly for the control valves of FIG. 2 in elevational section
  • FIG. 4 illustrates the drive arrangement for the pilot valves of FIG. 3 in top plane view
  • FIG. 5 is a developed, elevational, and partly sectional view of the device of FIG. 4.
  • FIG. 1 there is seen a swimming pool 1 connected by a suction line 2 to the intake end of a circulating pump 3.
  • a high-pressure conduit connects the discharge end of the pump 3 to two pairs of control valves 7, 8, and 9, 10, the conduit 15 leading directly to the intake ports of respective first valves 8, 9 in each pair.
  • the discharge ports of the first valves 8, 9 are coupled to the intake ports of the respective second valves 7, 10.
  • the discharge port of the valve 7 is connected by a low-pressure conduit 4 to the pool 1, and a similar conduit 5 connects the discharge port of the second valve 10 to a waste line 6 which may be a sewer or the like.
  • By-pass conduits ll, 12 lead from the coupled ports of the valves in the respective pairs to the two ends of a filter 13.
  • valves 7-10 In the first operating stage of the control arrangement represented in FIG. I by the valves 7-10, the valves 7 and 9 are open, and the valves 8 and 10 are closed.
  • the valves direct water taken from the pool 1 by the pump 3 through the filter 13 back to the pool 1. Impurities in the water are retained in the filter 13 in a conventional manner, not shown.
  • FIG. la shows the apparatus of FIG. I in a second operating stage in which the valves 8 and 10 are open, and the valves 7 and 9 are closed.
  • Water discharged from the pump 3 into the high-pressure conduit 15 is directed through the filter 13 in a direction opposite to the flow in the first-described sage so that the previously accumulated cake of impurities is dislodged and swept to the waste line 6.
  • valves 8, 9, and 10 are open, and the valve 7 is closed. Most of the water drawn from the pool 1 by the pump 3 flows directly into the waste line 6. Only a minor portion of the water stream can pass through the filter 13 because of the flow resistance of the latter, and sweeps residual impurities to the waste line. The mode of operation is not much afiected, if the valve 8 remains closed in the third operating stage.
  • FIGS. 2 to 5 The control arrangement with which this invention is more specifically concerned is illustrated in FIGS. 2 to 5.
  • FIG. 2 there is seen an assembly which combines the valves 7-10. It includes a unitary housing 14 which is divided into five flow chambers by integral, internal partitions 18. The chambers are arranged in a row. The central chamber 15' communicates with the high-pressure conduit 15 when the valves are assembled with other elements shown in FIG. 1, and two chambers are arranged symmetrically on either side of the central chamber 15, only the chambers l6, 17 on one side being explicitly shown in section. The following description of chambers 16 and 17 will be understood to be equally applicable to the two chambers on the other side of the central chamber.
  • the partitions 18 form respective valve seats of the valves 9, 10 in the chambers 16, I7 and define ports which directly couple the chamber 16 to the chamber 17, and the latter to the central chamber 15'.
  • Each chamber l6, 17 is provided with a releasable cover 21 having the shape of an inverted cup and sealingly engaging the housing 14 while spacedly extending over the valve seat and the port leading from the associated flow chamber toward the center of the row.
  • a diaphragm 20 of synthetic rubber is attached to each cover 21 in the valve structure so as to bound a valve operating chamber jointly with the cover.
  • a small throttling opening 19 having an effective flow section smaller than that of any portion of the prin cipal flow path through the valve arrangement connects the valve operating chamber of each valve with the next flow chamber toward the center in all positions of the diaphragm 20 which may move between a valve closing position shown in the valve 10 and a valve opening position seen in the valve 9.
  • the diaphragm 20 when in the valve closing position, engages the valve seat and also seals the intake port of the associated valve.
  • the discharge end of the flow chamber 16 is permanently open to the by-pass conduit 12 leading to one end of the filter l3, and the corresponding flow chamber of the valve 8 on the other side of the central chamber 15 is similarly open to the by-pass conduit 11.
  • the discharge port of the chamber 17 communicates with the lowpressure conduit 5 leading to the waste line 6, and the low-pressure conduit 4 leading to the pool 1 similarly communicates with the chamber of the valve 7.
  • the several conduits are represented in FIG. 2 only by corrugated hose nipples or bells for cemented connections to plastic pipes.
  • Small hose nipples 221, 222, 223, 224 on the covers 21 communicate with the valve operating chambers in the covers and are connected by flexible tubing (not shown) to corresponding nipples 221, 222', 223', 224 on the housing 24 of the pilot valve assembly seen in FIG. 3 on a scale larger than that of FIG. 2.
  • Partitions 25 divide the interior of the housing 24 into four chambers normally communicating with the nipples 221'-224 respectively, the nipples projecting into each chamber to form a valve seat 26 directed toward an open side of the housing 24. In the illustrated, assembled pilot valve assembly, this open side is covered by a sheet 29 of elastomeric plastic held in place by a cover 28 attached to the housing 24 by screws 32.
  • the sheet 29 engages the partitions 25 so as permanently to seal the several chambers in the housing 24 from each other and may be deflected toward and away from sealing engagement with the valve seat 26 in each chamber.
  • a cam shaft 31 is joumaled'in brackets integral with the cover 28 and fixedly carries four disc cams 301, 302, 303, 304 in radial alignment with the four valve seats 26.
  • a spherically curved cam follower integral with a motion transmitting plunger 27 is guided in an opening of the cover 28 toward and away from an enlarged portion of the sheet 29 above each valve chamber.
  • the cam followers are held in radial engagement with the cams on the shaft 31 by the resiliency, of the sheet 29, and cause movement of respective portions of the sheet toward and away from the valve seats 26 as the cam shaft 31 revolves.
  • tubing 331, 332 are permanently connected by tubing 331, 332 with a small nipple.500 on the conduit 5, and the chambers of the valves operated by the cams 303, 304 are connected by tubing 333, 334 to a small radial nipple 400 on the conduit 4.
  • control valve assembly In the angular position of the cam shaft 31 shown in FIG. 3 and the corresponding positions of the several cams 301-304 and plungers 27, the control valve assembly is set for operation as illustrated in FIG. 1.
  • valve seat on the nipple 224' is sealed by the cam 301 acting on the plastic sheet 29.
  • the pressure in the valve operating chamber becomes equal to that in the initially connected chambers 16, 17 by throttled liquid flowing through the diaphragm opening 19, and the diaphragm 20 of the valve 10 moves toward the closed position due to its resiliency.
  • it throttles flow between the chambers 16, 17, the pressure in the chamber 17, which is open to the low pressure conduit and the waste line 6, drops toward atmospheric pressure, while the pressure in the chamber 16 and the communicating valve operating chamber of the valve rises toward the pressure in the central chamber and in the high-pressure conduit 15 near the discharge end of the pump 3.
  • the diaphragm of the valve 10 ultimately is firmly pressed against its valve seat by the pressure difference.
  • valves 7, 8,.9 are opened and closed in the same manner when the associated cams 302-304 turn with the cam shaft 31.
  • the open nipples 221' and 223' cause the opening of the valves 7 and 9, while the sealed nipples 222', 224' hold the valves 8 and 10 closed, thereby establishing the flow pattern indicated by arrows in FIG. 1.
  • FIGS. 4 and 5 The drive mechanism which automatically turns the cam shaft 31 and thereby sets the positions of the control valves 7 to 10 in automatic sequence as shown in FIGS. 1 to 1b is illustrated in FIGS. 4 and 5.
  • the output shaft of a small synchronous motor 40 of the type employed in electric clocks drives the input member of a first step-down gear'transmission 41 whose output member turns a toothed timing wheel 42 once in 24 hours.
  • 24 Circumferentially distributed axial passages in the wheel 42 are dimensioned for frictionally holding pins 43 in a retracted position in which they project upwardly relatively far from the mounting plate 53 of the drive mechanism and in an operative position in which they are almost flush with the plate 53, only a handle on the operative pin projecting partly from the plate 53.
  • the pins 43 When in the operative position, the pins 43 engage a roller 44 during rotation of the wheel 42.
  • the roller 44 is mounted "on the free end of a resilient arm 45 which closes a microswitch 451 when depressed by a pin 43.
  • the microswitch 45 when closed, energizes a relay in the feed line of the electric motor which drives the pump 3, the relay, feed line, and pump motor not being shown, since they are entirely conventional.
  • the pump 3 thus operates as long as an operative pin 43 is held by the'wheel 42 within range of the roller 44.
  • the operative pin 43 also engages one of the uniformly spaced notches in the circumference of a second wheel 46 and angularly indexes the wheel 46 as long as the pump is operated by the pin.
  • the wheel 46 drives a second step-down gear transmission 47 whose output member 48 is provided with an axially projecting abutment 49 on its circumference.
  • the abutment 49 engages a mating abutment 51 on a circumferentially toothed coupling wheel 50 which is splined-to the cam shaft 31.
  • a knob 54 fixedly connected to the wheel 50 projects from the mounting plate 53 under the biasing force of a helical compression spring 56 interposed between the knob and the shaft 31 which normally holds the abutment 51 within range of the abutment 49.
  • the rim of gear teeth on the wheel 50 has a gap which, in the position of the apparatus seen in FIG. 4, is engaged by gear teeth of a wheel in the first transmission 41'.
  • the abutment 49 on the slowly rotating out-- put gear 48 engages the abutment 51 on the coupling wheel 50, the latter is turned sufficiently that the transmission 41 may mesh with the wheel 50 and turn the same together with the shaft 31 through 1 revolution until the gap in the toothed rim of the wheel 50 again faces the driving wheel in the transmission 41, and the wheel 50 is stopped by friction, particularly by the braking effect of a spring loaded ball 55 mounted on the plate 53 and radially engaging the knob 54.
  • the ball 55 also serves as a click stop for releasably arresting the knob 54 and the cam shaft 31 in selected angular positions when the knob is manually depressed against the biasing force of the spring 56 until three circumferentially distributed notches 57 in the knob are in a common radial plane with the ball 55.
  • the notches 57 are arranged in such a manner that the cams 301-304 hold the control valves 7-10 in the positions respectively illustrated in FIGS. 1, 1a, 1b upon engagement of the ball 55 with the notches of which only one is seen in FIG. 5.
  • the ball 55 also holds the knob 54 in the depressed axial position when engaging a notch 57.
  • the pump operates during each day for as many hours as coupling pins 43 are depressed into the operative position in the timing wheel 42.
  • the shaft 31 normally is in the position shown in FIG. 3, and the control valves are in the positions seen in FIGS. 1 and 2.
  • water is drawn from the pool 1, cleaned in the filter 13, and returned to the pool. 7
  • the wheel 50 couples the shaft 13 to the motor 40 when wheel rotation is initiated by the output gear 48, and the shaft 31 slowly turns through the valve positions of FIGS. 10 and 1b back to the starting position of FIG. 1.
  • the filter 13 is backwashed, and a portion of the water in the pool 1 is directly pumped into the waste line 6, thereby providing space in the pool for fresh water usually admitted by a float valve in a known manner, not shown.
  • the cams 301-304 are shaped in such a manner that the backwashing position of FIG. 1a is maintained during rotation of the shaft 31 through approximately 300, whereas draining occurs during an angular movement of the shaft through approximately 30.
  • the knob 54 provides a manual override which removes the coupling wheel 50 from an axial position of engagement with the output gear 48 of'the second transmission and with the first transmission 41, and permits the shaft 31 to be set manually for any one of the three operating stages.
  • a manually operated switch (not shown) is arranged parallel to the microswitch 451 to permit the pump to be energized during manual operation of the controls if the roller 44 should not .1
  • two non-illustrated threedway switches operated by the cams 302 and 304 may be arranged in series with the microswitch 451 in an obvious manner, not shown, to deenergize the pump when the valves 8, 9 are simultaneously in the same open position, as shown in FIG. lb, and for thereby preventing water loss from the pool 1 by drainage, if so desired, without otherwise modifying the control arrangement.
  • the cams 301-304 may be shaped to provide only the valve positions shown in FIGS. 1 and la, and such an arrangement may be preferred for pools which can be drained by gravity, or in which the water is replaced from a continuously running spring, the excess water being discharged by an overflow.
  • a control arrangement for controlling flow of water between a swimming pool, a filter, a pump, and a waste line which comprises:
  • each control valve having an intake port and a discharge port; b. coupling means connecting the discharge port of a first valve of each pair to the intake port of the second valve of said pair; c. high-pressure conduit means for connecting the intake ports of said first valves to the discharge end of said P p; d. two low-pressure conduit means for connecting the discharge ports of said second valves to said pool and to said waste line respectively; e. two by-pass conduit means for connecting said filter between said coupling means; and f. single operating means connected to each of said valves for operating the valves in a timed sequence in which the valves, when connected by said conduit means to said discharge end to the pump, to said pool, to said waste line, and to said filter, direct flow of water from said P p 1. in a first stage of said sequence through said filter in a first direction and to said pool, and
  • each of said control valves includes a valve seat and a flexible diaphragm
  • said operating means including means for generating a pressure differential across said diaphragm and for thereby moving the diaphragm toward and away from a position of sealing engagement with said valve seat.
  • said means for generating a pressure differential include a pilot valve operatively interposed between each valve operating chamber and one of said low-pressure conduit means, said single operating means include a cam shaft, a plurality of cams mounted on said cam shaft for rotation therewith and respectively associated with said pilot valves, and motion transmitting means connecting each cam to the associated pilot valve for opening and closing the pilot valve when the cam shaft is turned.
  • said operating means include a motor, coupling means interposed between said motor and said cam shaft, and coupling operating means responsive to the duration of said first stage for engaging said coupling means after a predetermined period of water flow from said pump through said filter to said pool.
  • said coupling operating means including a first wheel, a speed reducing transmission interposed between said motor and said first wheel for turning said wheel about an axis, a plurality of engaging members circumferentially mountedon said wheel for movement of each engaging member between an operative and an inoperative position, a second wheel, each engaging member when in the operative position and when said
  • said coupling means include a coupling wheel secured on said cam shaft against rotation while axially movable on said shaft toward and away from an axial position of driving engagement with said transmission.
  • said timed sequence including a third stage in which flow of water is directed by said control valves directly to said waste line.

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Water Supply & Treatment (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Details Of Reciprocating Pumps (AREA)
  • Mechanically-Actuated Valves (AREA)
US112315A 1970-04-23 1971-02-03 Control arrangement for a swimming pool filter Expired - Lifetime US3670893A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19702019691 DE2019691A1 (de) 1970-04-23 1970-04-23 Filter- und Rueckspuelvorrichtung fuer Schwimmbecken

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US3670893A true US3670893A (en) 1972-06-20

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US112315A Expired - Lifetime US3670893A (en) 1970-04-23 1971-02-03 Control arrangement for a swimming pool filter

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US (1) US3670893A (enrdf_load_stackoverflow)
DE (1) DE2019691A1 (enrdf_load_stackoverflow)
FR (1) FR2092285A5 (enrdf_load_stackoverflow)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4676914A (en) * 1983-03-18 1987-06-30 North Coast Systems, Inc. Microprocessor based pump controller for backwashable filter
US5906223A (en) * 1996-09-16 1999-05-25 Itt Industries, Inc. Chromatography valve assembly
US5937903A (en) * 1997-10-15 1999-08-17 Pac-Fab, Inc. High performance diverter valve
US6568428B2 (en) 1998-07-23 2003-05-27 Laars, Inc. Backwash valve
US20040040902A1 (en) * 2002-08-27 2004-03-04 Maax Inc. Self-cleaning water filtration system and method
US20080210309A1 (en) * 2007-03-01 2008-09-04 Randy Tan Diverter valve
US11136772B2 (en) * 2017-12-04 2021-10-05 Montasser M. Elsawi Swimming pool filtration system with means to spray backwash away from the system

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2645183A1 (de) * 1975-10-30 1977-05-12 Itt Ind Gmbh Deutsche Umwaelzpumpe
FR2538834B1 (fr) * 1983-01-04 1986-05-02 Tunzini Nessi Entr Equipements Installation de recyclage d'eau de piscines en vue de son traitement
FR2609904B1 (fr) * 1987-01-27 1989-05-05 Quero Claude Dispositif complementaire de filtration adapte aux piscines a goulotte
US5244585A (en) * 1991-01-11 1993-09-14 Akitoshi Sugimoto Method of cleaning porous ceramic filters

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3512644A (en) * 1967-06-28 1970-05-19 Jacuzzi Bros Inc Automatic filter backwash assembly
US3581895A (en) * 1969-02-28 1971-06-01 Herbert H Howard Automatic backwashing filter system for swimming pools
US3616915A (en) * 1969-05-15 1971-11-02 Aquamatic Inc Automatic filter control

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3512644A (en) * 1967-06-28 1970-05-19 Jacuzzi Bros Inc Automatic filter backwash assembly
US3581895A (en) * 1969-02-28 1971-06-01 Herbert H Howard Automatic backwashing filter system for swimming pools
US3616915A (en) * 1969-05-15 1971-11-02 Aquamatic Inc Automatic filter control

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4676914A (en) * 1983-03-18 1987-06-30 North Coast Systems, Inc. Microprocessor based pump controller for backwashable filter
US5906223A (en) * 1996-09-16 1999-05-25 Itt Industries, Inc. Chromatography valve assembly
US5937903A (en) * 1997-10-15 1999-08-17 Pac-Fab, Inc. High performance diverter valve
US6568428B2 (en) 1998-07-23 2003-05-27 Laars, Inc. Backwash valve
US20040040902A1 (en) * 2002-08-27 2004-03-04 Maax Inc. Self-cleaning water filtration system and method
US6958118B2 (en) * 2002-08-27 2005-10-25 Maax, Inc. Self-cleaning water filtration system and method
US20080210309A1 (en) * 2007-03-01 2008-09-04 Randy Tan Diverter valve
US7849877B2 (en) 2007-03-01 2010-12-14 Zodiac Pool Systems, Inc. Diverter valve
US8910662B2 (en) 2007-03-01 2014-12-16 Zodiac Pool Systems, Inc. Diverter valve
US11136772B2 (en) * 2017-12-04 2021-10-05 Montasser M. Elsawi Swimming pool filtration system with means to spray backwash away from the system

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Publication number Publication date
FR2092285A5 (enrdf_load_stackoverflow) 1971-01-21
DE2019691A1 (de) 1972-01-20

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