US3067879A

US3067879A - Skim tank

Info

Publication number: US3067879A
Authority: US
Inventors: William O Baker
Original assignee: Swimquip Inc
Current assignee: Swimquip Inc
Priority date: 1959-02-02
Filing date: 1959-02-02
Publication date: 1962-12-11
Anticipated expiration: 1979-12-11

Description

W. O. BAKER SKIM TANK Dec. 11, 1962 2 Sheets-Sheet l PUMP Filed Feb. 2, 1959 FILTER Dec. 11, 1962 w. o. BAKER SKIM TANK Filed Feb.

IN V EN TOR. Wl. z. /AM 50,65@

United States Patent Oilice 3,@i779 Patented Dec. 11, 1962 3,067,879 SKIM TANK William 0. Baker, West Covina, Calif., assigner to Swimquip, lne., El Monte, Calif., a corporation of Callif'ornia Filed Feb. 2, w59, Ser. No. 790,629

11 Claims. (Cl. 2MP- 129) This invention relates to swimming pool equipment, and particularly to circulating apparatus for maintaining the water of the pool in clean condition.

The usual swimming pool installation includes apparatus for withdrawing water from the pool in three ways. (l) A skimmer withdraws surface water for removing suspended matter that rises to the surface. (2) A vacuum cleaning attachment is used to remove by suction solid material that adheres to or is located at the walls and bottom of the pool. (3) A main drain at the deepest portion of the pool creates a llow at the floor of the swimming pool; by the aid of a brush, matter at the bottom of the pool is urged into the flow stream toward the main drain.

Of course, water removed from the pool is reused after suspended matter is liltered out. For this purpose, a filter and pump are used that receive all water removed from the pool.

Various fittings, valves and conduits have in the past been provided for purposes of determining the desired operation of the swimming pool; skimming, vacuuming or draining. Skimming depends upon gravity ilow over a skimming ledge, as, for example, a ledge provided by a oating Weir structure. Flow through a vacuum line depends upon low pressure or suction at the inlet side of the pump being transferred to the very head of the vacuum cleaning attachment. Usually flow from the m'ain drain also depends upon suction for the reason that a pump is, more often than not, located virtually at the level of the surface of the pool.

It has been proposed to utilize a combination tank that will simplify the various connections that must be made to a swimming pool. A typical tank of this character is generally cylindrical, with an upper opening accessible at the poolside decking. The cylindrical tank has a branch neck in which the floating Weir is installed. In the bottom of the tank is a fitting for effluent water passing to the .pump inlet. Accommodated in the bottom of the tank is a diatomaceous earth filter through which all water must pass on its way to the pump. A strainer basket may also be provided in the tank.

In lsuch organizations, it is, of course, necessary that all water owing from the pool and intended to be recirculated thereto pass through the filter structure. Ac-

cordingly, it has been proposed to provide an inlet into .the tank, for example, that communicates with a vacuum cleaning connector in the pool. But since operation of a vacuum cleaningr attachment depends upon suction whereas operation of a skimming ledge depends upon gravity, it is clear that the intended iiow through a vacuum cleaning attachment can be provided only by confining flow to the vacuum cleaner attachmment. It has been proposed that this be accomplished by the aid of a removable suction lid fitted in the tank beneath the branch neck.

The basic disadvantage of the structure just described lis that the suction lid must of necessity be stored and it is a nuisance periodically to remove it from its storage place. Another disadvantage is that during intended skimming operations the level of water in the pool may fall critically and to such a point that the pump will suck air through the tank even if the line from the vacuum cleaning attachment is left open.

The primary object of this invention is to overcome the foregoing disadvantages and to provide an improved skim tank incorporating novel features of operation.

This object is accomplished by the novel use of a floating weir structure. The weir itself serves as a means for preventing skim flow whereby suction can be transferred either to a vacuum cleaning attachment or to a main drain. Furthermore, the weir itself serves as a protective device that establishes suction for liow from the main drain or a bypass conduit upon a critical lowering in the level of water in the pool. In this manner, a charge for the pump is always maintained, and more important, this function is automatically accomplished.

Still another object of this invention is to provide a new skim tank which, in one embodiment, serves as an effective means for making all necessary conduit connections for the circulation system of a swimming pool, including connections for a vacuum attachment, main drain and pump inlet, and which, in another embodiment (diifering only in slight detail from the first), serves as an effective pump inlet protective device, independently of vacuum attachments and the like.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of several embodiments of the invention. For this purpose, there are shown a few forms in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURE l is a pictorial view illustrating the improved skim tank, adjacent portions of the swimming pool being illustrated in phantom line;

FG. 2 is a vertical sectional view of the skim tank, a filter and pump being diagrammatically illustrated;

EEG. 3 is a front elevation view illustrating another embodiment of the invention in which vacuuming and circulation from a main drain are accomplished independently of the skim tank; FIG. 4 is an enlarged sectional view taken along the plane indicated by line 4-4 of FIG. 3;

FIG. 5 is an end view of the fitting opening into the tank; and

FG. 6 is an enlarged sectional view taken along the plane indicated by line 6-6 of FIG. 4.

ln FiG. l, there is illustrated a skim tank 1 fabricated of brass, copper or other suitable material. The tank 1 is generally of hollow, box-like configuration, having an upper rectangular opening 2 (FIG. 2). The tank includes side wall sections 3, a rear wall section 4, a bottom rectangular wall section 5, and a front wall section 6.

The front wall section 6 is made of upper and lower wall parts aa and 6b. Part 6a hasa horizontal, forwardly extending integral ledge; and part 6b has an upwardly inclined integral ledge cooperating with the ledge of part 6a to defined a lateral channel 7 into the tank. y

The

side wall sections

3 and 4 both conform to the angular contour of the front wall parts 6a and 6b to complete the Ichannel 7. Surface water from the pool 8 flows into this channel.

The various wall sections are secured appropriately together to complete the box-like structure, as by brazing, soldering or the like.

The lateral channel 7 for the tank l communicates with the surface of the pool proper. For this purpose, the tank is embedded in the ground V9 in the desired orientation and at the appropriate depth. A wall 10 of the pool provides an opening 11 registering at its throat with the channel 7. The lower wall of opening 11 slants downwardly from a crest 11a located at the pool side of the opening.

The upper opening 2 of the tank 1 registers with an access hole 12 in the poolside decking 13, the access hole 12 being closed by a removable cover 14 of cast iron or aluminum alloy. The cover is supported in fiush relationship to the poolside decking 13 by the aid of a cover frame 15 embedded in the decking and which defines the access hole 12.

A floating weir 16 (FIG. 2) is supported by the upwardly sloping ledge of the lower front wall part 6b for angular movement about a horizontal axis substantially coincident with the lower portion of the weir 16. The Weir 16 is rectangular, and conforms to the dimensions of the lateral tank channel 7. Hence, fiow into the tank is confined to a path over the top edge of the weir in a customary manner.

The weir 16 is supported upon a bracket plate 17 located within the tank 1. The bracket plate 17 is generally rectangular in coniiguration to fit the interior of the tank 1. One end of the bracket plate is secured to an intermediate, horizontally extending offset portion 4a of the rear wall 4l. bracket 17 is secured to the upwardly sloping angled portion of the front wall section 6b. The bracket 17 extends from the rear wall 4 to the front wall part 6b and it thus divides the tank 1 into two spaces. These spaces are in communication with respect to each other by the aid of a rectangular opening 18 in the bracket 17. The space above the bracket 17 of course includes the lateral channel 7 and houses the weir 16.

The Weir comprises a foam plastic or other buoyant float 20, trapezoidal in cross-section, and an enclosing or covering sheet 19, also preferably made of plastic. The sheet covering material 19 encloses all but the ends of the buoyant foat 2t). At least one edge of the sheet 19 forms an integral tab 19a at a corner of the fioat that serves as a means for mounting to the bracket 17. A series of nuts and bolts 21 secure the tab 19a `to an upwardly extending fiange 22 of the bracket 17 (see FIG. 4 for an enlarged View of this structure). The covering material 19, being made of iiexible plastic, serves as a fiexible hinge and permits the weir to move angularly about the tab 19a.

The Weir 16 operates in a Well-understood manner when water is withdrawn from the tank 1. Leaves and other debris are trapped behind the weir.

To withdraw water from the tank 1, a conventional pump illustrated by the block 23 is provided. The pump inlet communicates with the tank by way of a conduit 24, an elbow 25, and a fitting 26 accommodated in an opening in the bottom wall S of the tank 1.

In the bottom of the tank 1 is a strainer basket 27 through which all water must iiow. The basket 27 in this `instance is supported by fianges 28 secured to the rear wall 4, the front wall part 6b and the side walls 3, all beneath the bracket 17. The basket 27 accordingly collects larger debris. The basket can be periodically removed for cleaning through the upper opening 2 of the tank 1.

A filter unit 29 receives the discharge from the pump 23. Water from the filter 29 returns to the pool by an appropriate fitting (not shown). By enlargement of the tank 1, a filter, such as of the diatomaceous type, obviously can be accommodated therein in place of the filter 29.

For purposes of cleaning the swimming pool, water is either withdrawn from the pool via the main drain or through a vacuum attachment. In the present example, a vacuum fitting and a main drain fitting are both provided at the tank 1.

A conduit 3) extends from the main drain of the pool The other edge of the (not shown). The conduit 30 connects with the interior of the tank 1 beneath the bracket 17 by the aid of an elbow 31 and a fitting 32 secured at an opening in the vertical portion of the front wall part 6b (see also FIG. l). A Vacuum connector 33 exposed to the water in the pool is also adapted to communicate with the tank 1 beneath the bracket 17. For this purpose, a fitting 34, mounted at a second opening in the vertical portion of the front wall part 6b, and a nipple attached to the fitting and the connector 33 are provided. A plug normally closes the conduit 35 by being accommodated in the connector 33.

If it is desired to divert the total fiow through the main drain of the pool, a direct connection between the main drain and the pump is established. This is accomplished by manually moving the Weir 16 against the bracket 17 so that it seals the opening 18, access being provided via the upper opening 2 in the tank 1. The suction created by the pump 23 beneath the bracket 17 is sufficient to hold the weir closed against the buoyant forces exerted thereon. The bracket 2S is, of course, relatively rigid, and hence provides a firm surface to which the pliable covering sheet can conform to establish a desirable water seal. The trapezoidal configuration of the fioat 20 ensures that the lower or inner surface of the weir 16 is substantially coplanar with the bracket at the instant of initial engagement therewith.

To restore the weir 16 to its normal orientation, the vacuum beneath the bracket 17 is broken. This can be achieved by either momentarily stopping the pump 23 or by forcing the weir upwardly away from the bracket.

Vacuuming of the pool is accomplished similarly. However, the plug in the connector 33 is removed and inserted into the main drain fitting 32 from the inside of the tank. The vacuum attachment is installed at the connector 33 and the wer 16 is again placed against the bracket opening 1S.

The advantage of the foregoing arrangement may be appreciated in terms of valve structures that are avoided. No valves are needed between the main drain and the pump, or between the vacuum line and the pump, 0r bctween the skimmer and the pump. Achieving any mode of operation is a simple matter. For skimming, a desired small ratio of flow from the main drain for circulating heavy chemicals is achieved by virtue of conduit 30 and the location of its end close to, but beneath the level of water in the tank 1, the vacuum connector 33 being plugged and the fitting 32 being open; for vacuuming, the plug in the end of the connector 33 is placed in the fitting 32 from the inside of the tank and the Weir is depressed; and for causing total flow from the main drain, the vacuum connector 33 is plugged, the fitting 32 opened, and the weir depressed.

During normal skimming operation, that is, when neither vacuuming nor brushing is desired, the fioating Weir 16 occupies a definite position relative to the level of water in the pool 8 for any given rate of operation of the pump. Except for transient conditions, the Weir Oc cupies a position such that the demands of the pump are precisely satisfied. This equilibrium position thus exists when the fiow into the tank precisely equals flow out of the tank which is demanded by the pump. For example, the pump may be exactly supplied if the operative edge of the Weir is an eighth of an inch below the surface of the water in the pool. Of course, this dimension is entirely arbitrary since it depends upon the total tiow of water induced by the pump and other factors. This relative equilibrium position of the weir is achieved despite fluctuations in the level of the water in the pool. The reason for this may be appreciated by assuming that the Weir occupies a position different from the equilibrium position. Thus, if the weir rises relative to the level of water in the pool (or if the level of the water in the pool falls` relative to the Weir), the edge of the weir is less than 1/s" below the water level. Hence, the volume of Water in the tank 1 will be reduced. Buoyant forces are correspond-v ingly reduced, and consequently the Weir must fall until the 1/s spacing is restored. Conversely, if the weir falls relative to the level in the pool so that the spacing of the Weir edge from the pool level is more than Ms, then the volume of water in the tank will obviously be increased. Buoyant forces are accordingly increased, and consequently the Weir must rise until the equilibrium position is restored.

During normal operation, the main drain is left open and a slight low exists from the main drain via conduit 30, elbow 31 and fitting 32 to the tank l. This flow induced by the slight diierence between the level of water in the pool and that in the tank l causes a slight circulation through conduit 3i) which will redistribute those chemicals that are heavier than water while the major percentage of llow occurs over the Weir. This flow from the main drain slightly alters the expected equilibriumposition of the weir 16 but, in principle, the operation of the floating Weir is as previouslydescribed.

in a manner to be presently described, the main drainconnection to the tank, together with the oating Weir cooperating with the bracket opening i8, ensures that a charge will be maintained for the pump. Thus, lowering of the level of the weir ld is expected to increase the ow from the pool to supply the needs of the pump; yet this is not possible if the water level in the pool recedes close to the crest lla. As an example, the Water level Within the pool may be lowered to a point relative to the xed lower ledge lia such that flow of water into the filter tank l. will be inadequate to supply the pump requirements. The water level within the skimmer tank will then rapidly be lowered, this in turn reducing the buoyancy and position of the Weir i6 until the weir becomes a valve in contact with bracket 17.

Engagement of the Weir 16 with the bracket 17 now creates a direct connection between the main drain conduit 3@ and the pump through the lower portion of the tank ll which is now sealed from atmosphere. The Weir 16 is held in position by the slight amount of vacuum created in the piping and exerted over the entire surface of the Weir lo.

Due to the draw created on the Weir le by virtue of the flow of the water from the tank and induced by the pump, the Weir will close prior to the tank being cornpletely empty, thus leaving adequate water surrounding this newly formed closure at bracket 17 to provide an airtight seal.

The tank is so designed that the Weir lo is substantially above the opening 18 during normal operation. This ensures against premature closure of the opening by virtue of drag upon the weir.

In FIGS. 3 and 4, there is illustrated a tank Si for use in an installation where there are other provisions for vacuum cleaning attachments and main drain iittings. The main difference between the tank Si and the tank l is that there is but one opening into the tank beneath the bracket i7. An interiorly threaded tting 52 is mounted in the vertical portion of the wall section 6b. A nipple 53 cooperates with the fitting 52 at one end and projects horizontally through the wall of the poot to a second fitting 54 that opens into the pool somewhat below the normal water level.

By the aid of the conduit 53 and the iitting :'52, it is ensured that a charge will be provided for the pump should the weir i6 seat against the bracket i7. A check valve unit, however, normally closes passage through the conduit d3 vand opens only when the weir 16 seats.

The check valve unit, as shown in FIGS. 5 and 6, includes a body S5 exteriorly threaded for reception into the tting 52 from the inside of the tank. The body 55 has an outwardly extending annular flange 56 at one end limiting inward movement of the body. The body 5S has an niner wall 57 provided with a generally rectangular port 5d communicating `vith the end of the nipple S3.

A circular, iiexibie, resilient closure 59 lits against the end wall S7 and normally closes the opening 58. For this purpose, it is held in position by a bar 60 extending diametrically of the disk closure 59. Cap screws 6 2 pass through aligned apertures in the har 60 and the disk 59 and cooperate with threaded apertures 6l in the end wall 57. These apertures are so located that the bar 60 extends across the short dimension of the aperture or port 58. The sides of the closure 59 are capable of tlexure inwardly and about an axis defined generally by the bar 6i? to Iopen the port 58 when there is a preponderance of pressure toward the left, as viewed in FIG. 7. The resilience of the closure 59 normally maintains it in sealing engagement with the wall 57 beyond the edges of the opening 5S. T he closure S9 readily opens in response to increased pump suction, as upon closure of the bracket opening. A path of ow from the pool is provided via the conduit 53.

A ported plug 63 providing a series of small openings 64;- is accommodated in the tting 54 at the end of the nipple 53 opening in the side of the pool. The plug 63 ensures against entrance of larger objects. If it is desired, a vacuum attachment may be substituted for the ported plug 63 to achieve the operation as described in c011- nection with the previous form.

The inventor claims:

l. For use with a closed circuit circulatory system `,for a swimming pool having a main drain or the like: a skim tank having two adjoining portions, one of the portions having means forming a channel for ingress of` surface water from a swimming pool; the other of the portions be.- ing adapted to Vreceive water from said one portion; said other skim tank portion having means Afor egress of water from the tank and to a pump; said pump being for withdrawing water from the other tank portion; a levelresponsive movable weir in said one tank portion, and deiining the terminus of said channel to control flowof water into said other tank portion; said weir having means operable upon movement thereof for closing communication between the tank portions and in response to a su-bstantial lowering of the level in said tank; said .tank having an upper opening for access to said movable Weir whereby the weir can be moved to close communication between the tank portions independently of the Vwater level in the tank, suction in said other tank portion maintaining the weir in closed position; and conduit means connecting the main drain of said pool to said other tank portion, and permitting iiow independently of the level of liquid in said tank.

2. For use with a closed circuit circulatory system for a swimming pool or the like: a skim tank having two adjoining portions, one of the .portions having means forming a channel for ingress of surface water Afrom a swimming pool; the other of the portions being `adapted to receive water from said one portion; said other skim tank portion having means for egress of water from the tank and to a pump; said pump being yfor withdrawing water from the other tank portion; a level-responsive weir in said one tank portion, and defining the terminus of said channel to control iiow of water into saidother tank portion; said weir having means for closing .communication between the tank portions and in 'response to a substantial lowering of the level in said tank; corninit means extending from said other ltank portion and extending to the pool at a place beneath .the sunface thereof and permitting flow from saidl pool to said ,tank portion independently of the level of liquid in said tank; and a check valve in said conduit means and operative to bypass water into said other tank portion in response to interruption of communication between the tank portions.

3. For use with a-closed circuit circulatory system for a swimming pool having a main drain or the like: a skim tank having two adioining portions, one ofthe-portions having means forming a channel 'for ingress of surface water from a swimming pool; the other of the portions being adapted to receive water from said one portion; said other skim tank portion having means for egress of water from the tank and to a pump; said pump being for withdrawing water from the other tank portion; a levelresponsive buoyant movable weir in said one tank portion, and defining the terminus of said channel to control ow of water into said other tank portion; said weir having means operable upon movement thereof for closing communication between the tank portions and in response to a substantial lowering of the level in said tank; a pair of iittings mounted on the tank at said other tank portion; iirst conduit means from one of said fittings to the main drain of said pool and forming a bypass into said other tank portion when communication between the tank poritons is interrupted; and second conduit means from the other of said fittings and extending to the pool at a place adjacent but beneath the surface thereof; and a plug designed to tit both conduit means for detachable engagement with one of them to close the corresponding conduit means, the other conduit means permitting tiow to the corresponding titting independently of the levei of liquid in said tank; said tank having an access opening for manually moving said weir to closed position against the buoyant forces acting upon said Weir for inducing total pump tlow through a selected one of said conduits.

4. For use with a closed circuit circulatory system for a swimming pool or the like: a skim tank having side walls, a bottom wall, a rear wall and a pair of angled upper and lower front wall sections having parts defining a channel into which surface water from said pool is adapted to ow; a bracket extending across the tank beneath said channel, and having an opening therein; said bracket defining a tank part communicating with the channel only via said bracket opening; a floating weir mounted by said tank at said lower front wall section for angular movement between said side walls and about a substantially horizontal axis defining the terminus of said channel, and closing said opening upon movement thereof toward said bracket, the Weir being movable toward said bracket in response to lowering of the level of water in the tank; said tank part having an opening for etiiuent water; and bypass means permitting flow from said pool to said tank part independently of the level of liquid in said tank part.

5. For use With a closed circuit circulatory system for a swimming pool or the like: a skim tank having side walls, a bottom wall, a rear Wall and a pair of angled upper and lower front wall sections having parts defining a channel into which surface water from said pool is adapted to ow; a bracket extending across the tank beneath said channel, and having an opening therein; said bracket detining a tank part communicating with the channel only via said bracket opening; a iioating Weir mounted by said tank at said lower front wall section for angular movement between said side walls and about a substantially horizontal axis defining the terminus of said channel, and closing said opening upon movement thereof toward said bracket, the Weir being movable toward said bracket in response to lowering of the level of water in the tank; said tank part having an opening for eiuent water; bypass means permitting iiow from said pool to said tank part independently of the level of liquid in said tank part; a removable lter means having a peripheral flange; and wall means in said tank part on opposite 4sides of which the eliiuent opening and the bracket are respectively located; said wall means having an opening; said peripheral ange of said iilter means resting upon the edges about said opening of said wall means; said filter means being removable through the bracket opening.

6. For use with a closed circuit circulatory system for a swimming pool having a main drain or the like: a skim tank having two adjoining portions, one of the portions having means forming a channel for ingress of surface water from a swimming pool; the other of the por tions being adapted to receive water from said one portion; said other skim tank portion having means for egress of water from the tank and to a pump; said pump being for withdrawing water from the other tank portion; a level-responsive movable weir in said one tank portion, and dening the terminus of said channel to control tlow of Water into said other tank portion; said Weir having means operable upon movement thereof for closing cornmunication between the tank portions and in response to a substantial lowering of the level in said tank; said tank having an upper opening for access to said movable weir whereby the weir can be closed to close communication between the tank portions independently of the Water level in the tank, suction in said other tank portion maintaining the weir in closed position; a sealing plug; a first and second conduit each opening at one end at said other tank portion, the first of said conduits including a connector at its other end, said first conduit having provisions for detachably receiving said plug; means ac cessible at the said one end of the second conduit for selective reception of said plug; the other end of said other conduit being connected to the main drain of said swimming pool; one of said conduits permitting bypass iiow from said pool to said other tank portion independ- `ently of the level of liquid in said tank.

7. For use with a closed circuit circulatory system for a swimming pool or the like: a skim tank having two adjoining portions, one of the portions having means forming a channel for ingress of surface water from a swimming pool; the other of the portions being adapted to rcceive Water from one said portion; said other skim tank portion having means for egress of Water from the tank to a pump; a level-responsive weir defining the terminus of said channel and located in said one tank portion, and controlling iiow of water into said other tank portion from said one tank portion; said level responsive weir being movable in response to buoyant forces imposed thereon to adjust flow into said tank to meet the demands of said pump; said one tank portion having an edge over which water must iiow to reach said Weir; said weir `being movable, in response to a lowering of the level of water in the tank, to and below the level of said edge, said Weir upon movement below said level being incapable of increasing iiow into said tank; means operated only by movement of the weir substantially below said level to close communication between said tank portions; and bypass means from the pool admitting water into said other tank portion and permitting flow of water from the pool to said other tank portion independently of the level of liquid in said tank.

8. in a closed circuit circulation system for a contained main body of water having means forming a tank open to atmosphere and separate from the main body of water, a pump having an inlet and an outlet, means connecting the tank to the pump inlet, means forming a channel for flow of water from the surface of said body of water to the tank, means connecting the pump outlet to the main body of water, and a skimming device detining the terminus of said channel for regulating the flow of water from the main body of water into the tank, the combination with the skimming device of: means responsive to cessation of skimming for automatically closing communication between atmosphere and the pump inlet via the tank; and means forming a by-pass -between the main body of water and the tank, and in communication with the pump inlet independently of said automatically operable closing means; said bypass means permitting tlow to the pump inlet independently of the level of water in said tank.

9. The combination as set forth in claim 8 in which the skimming device is responsive at least partially to the height of water in the tank for maintaining tlow for the pump inlet; the combination being further characterized by the provision of means delining a critical level in the said channel which must be exceeded by the main body of Water in order to provide any flow over the skimming device; said automatically operable closing means responding to the diierentiai between the ilow demanded by said pump and the ow provided over said skimming device whereby closing of communication between atmosphere and said pump inlet via said tank is accomplished in actual anticipation of skimming cessation.

10. In a closed circuit circulation system for a contained main body of Water: means forming a tank open to atmosphere and a seat therein; a pump having an inlet and an outlet; means connecting the pump inlet to the tank; means forming a channel for oW of water from the surface of said body of water to the tank; means connecting the pump outlet to the main body of water; communication between said channel and said pump inlet be ing established via said seat; the communication between the tank and the atmosphere being beyond the space included between the seat and the pump inlet; a skimming device defining the terminus of said channel and located beyond said space; said skimming device being movable 'in -a path in response to the level of water in the tank to regulate the ilow from said channel and to maintain required ow to the pump inlet; a closure carried by the skimming device for engaging the seat when the skimming device reaches a limit in its said path corresponding to excess demand by said pump with respect to flow into said tank; and means forming a by-pass between the main body of Water andthe tank for meeting the demands of the pump independently of skimming action; said bypass lforming means permitting ow of water to the tank independently of the level of water in said tank.

11. The combination as set forth in claim 10 in which the skimming device comprises a buoyant weir so placed that one side of the Weir is engageable with the seat, the buoyant forces acting upon said weir during normal operation thereof maintaining the weir away Ifrom said seat.

References Cited in the file of this patent UNITED STATES PATENTS 195,175 Schmitz Sept. 11, 1877 1,191,628 Trinks July 18, 1916 1,572,964 Sanders Feb. 16, 1926 2,045,909 Haralson June 30, 1936 2,252,687 Bassett Aug. 19, 1941 2,446,384 Murdock Aug. 3, 1948 2,701,235 King Feb. 1, 1955 2,739,939 Leslie Mar. 27, 1956 2,740,422 Schilling Apr. 3, 1956 2,809,752 Leslie Oct. 15, 1957 2,844,255 Cavenah et al July 22, 1958 2,914,180 Konopka Nov. 24, 1959 2,979,206 Konopka et al. Apr. 11, 1961 FOREIGN PATENTS 348,794 Great Britain May 2l, 1931